CHROMIUM_VERSION

@@ -1 +1 @@
-104.0.5112.79
+105.0.5195.52

src/AUTHORS

@@ -22,6 +22,7 @@ Abhinav Vij <abhinav.vij@samsung.com>
 Abhishek Agarwal <abhishek.a21@samsung.com>
 Abhishek Kanike <abhishek.ka@samsung.com>
 Abhishek Singh <abhi.rathore@samsung.com>
+Abin K Paul <abin.paul1@gmail.com>
 Abul Hasan Md Osama <ahm.osama@samsung.com>
 Adam Bonner <abonner-chromium@solscope.com>
 Adam Bujalski <abujalski@gmail.com>
@@ -57,6 +58,7 @@ Alex Gaynor <alex.gaynor@gmail.com>
 Alex Henrie <alexhenrie24@gmail.com>
 Alex Scheele <alexscheele@gmail.com>
 Alexander Douglas <agdoug@amazon.com>
+Alexander Forrence <alex.forrence@gmail.com>
 Alexander Guettler <alexander@guettler.io>
 Alexander Rezepkin <etu@vivaldi.net>
 Alexander Shalamov <alexander.shalamov@intel.com>
@@ -181,6 +183,7 @@ Brian Yip <itsbriany@gmail.com>
 Brook Hong <hzgmaxwell@gmail.com>
 Bruno Calvignac <bruno@flock.com>
 Bruno de Oliveira Abinader <brunoabinader@gmail.com>
+Bruno Pitrus <brunopitrus@hotmail.com>
 Bruno Roy <brusi_roy@hotmail.com>
 Bryan Donlan <bdonlan@gmail.com>
 Bryce Thomas <bryct@amazon.com>
@@ -382,6 +385,7 @@ Gajendra Singh <wxjg68@motorola.com>
 Ganesh Borle <ganesh.borle@samsung.com>
 Gao Chun <chun.gao@intel.com>
 Gao Chun <gaochun.dev@gmail.com>
+Gao Yu <wanggao@tencent.com>
 Gaurav Dhol <gaurav.dhol@einfochips.com>
 Gautham Banasandra <gautham.bangalore@gmail.com>
 George Adams <geoada@amazon.com>
@@ -471,6 +475,7 @@ Irmak Kavasoglu <irmakkavasoglu@gmail.com>
 Isaac Murchie <murchieisaac@gmail.com>
 Isaac Reilly <reillyi@amazon.com>
 Ivan Naydonov <samogot@gmail.com>
+Ivan Pavlotskiy <ivan.pavlotskiy@lgepartner.com>
 Ivan Sham <ivansham@amazon.com>
 Jack Bates <jack@nottheoilrig.com>
 Jacky Hu <flameddd@gmail.com>
@@ -512,6 +517,7 @@ Jay Soffian <jaysoffian@gmail.com>
 Jeado Ko <haibane84@gmail.com>
 Jeffrey C <jeffreyca16@gmail.com>
 Jeffrey Yeung <jeffrey.yeung@poly.com>
+Jelle Bleyaert <jellebley@gmail.com>
 Jeong A Shin <jeonga@khu.ac.kr>
 Jeongeun Kim <je_julie.kim@samsung.com>
 Jeongmin Kim <kimwjdalsl@gmail.com>
@@ -700,6 +706,7 @@ Lenny Khazan <lenny.khazan@gmail.com>
 Leo Wolf <jclw@ymail.com>
 Leon Han <leon.han@intel.com>
 Leung Wing Chung <lwchkg@gmail.com>
+Li Yanbo <liyanbo.monster@bytedance.com>
 Li Yin <li.yin@intel.com>
 Lidwine Genevet <lgenevet@cisco.com>
 Lin Sun <lin.sun@intel.com>
@@ -907,6 +914,7 @@ Pedro Tôrres <t0rr3s.p3dr0@gmail.com>
 Peng Hu <penghu@tencent.com>
 Peng Jiang <leiyi.jp@gmail.com>
 Peng Xinchao <pxinchao@gmail.com>
+Peng Zhou <zhoupeng.1996@bytedance.com>
 Peng-Yu Chen <pengyu@libstarrify.so>
 Pei Wang <wangpei@uniontech.com>
 Peter Bright <drpizza@quiscalusmexicanus.org>
@@ -938,6 +946,7 @@ Praveen Akkiraju <praveen.anp@samsung.com>
 Preeti Nayak <preeti.nayak@samsung.com>
 Pritam Nikam <pritam.nikam@samsung.com>
 Puttaraju R <puttaraju.r@samsung.com>
+Qi Tiezheng <qitiezheng@360.cn>
 Qi Yang <qi1988.yang@samsung.com>
 Qiang Zeng <zengqiang1@huawei.com>
 Qiankun Miao <qiankun.miao@intel.com>
@@ -1140,10 +1149,12 @@ Sungmann Cho <sungmann.cho@navercorp.com>
 Sunil Ratnu <sunil.ratnu@samsung.com>
 Sunitha Srivatsa <srivats@amazon.com>
 Sunwoo Nam <jegalzz88@gmail.com>
+Suresh Guttula <suresh.guttula@amd.corp-partner.google.com>
 Surya K M <suryagowda590@gmail.com>
 Sushma Venkatesh Reddy <sushma.venkatesh.reddy@intel.com>
 Suvanjan Mukherjee <suvanjanmukherjee@gmail.com>
 Suyambulingam R M <suyambu.rm@samsung.com>
+Suyash Nayan <suyashnyn1@gmail.com>
 Suyash Sengar <suyash.s@samsung.com>
 Swarali Raut <swarali.sr@samsung.com>
 Swati Jaiswal <swa.jaiswal@samsung.com>
@@ -1159,6 +1170,7 @@ Taehoon Lee <taylor.hoon@gmail.com>
 Taeseong Yu <yugeeklab@gmail.com>
 Taeyeon Kim <ssg9732@gmail.com>
 Tae Shin <taeshindev@gmail.com>
+Taher Ali <taher.dasten@gmail.com>
 Takaaki Suzuki <takaakisuzuki.14@gmail.com>
 Takahiro Aoyagi <hogehoge@gachapin.jp>
 Takashi Fujita <tgfjt.mail@gmail.com>
@@ -1329,6 +1341,7 @@ Zheng Xu <zxu@kobo.com>
 Zhengkun Li <zhengkli@amazon.com>
 Zhenyu Liang <zhenyu.liang@intel.com>
 Zhenyu Shan <zhenyu.shan@intel.com>
+Zhibo Wang <zhibo1.wang@intel.com>
 Zhifei Fang <facetothefate@gmail.com>
 Zhiyuan Ye <zhiyuanye@tencent.com>
 Zhuoyu Qian <zhuoyu.qian@samsung.com>
@@ -1383,6 +1396,7 @@ Loongson Technology Corporation Limited. <*@loongson.cn>
 Macadamian <*@macadamian.com>
 Mail.ru Group <*@corp.mail.ru>
 Make Positive Provar Limited <*@provartesting.com>
+Mc Zeng <zengmcong@gmail.com>
 Mediatek <*@mediatek.com>
 Microsoft <*@microsoft.com>
 MIPS Technologies, Inc. <*@mips.com>

src/DEPS

@@ -144,6 +144,19 @@ vars = {
   # tools/clang/OWNERS before depending on it.
   'checkout_clang_libs': 'use_rust',
 
+  # Fetch prebuilt and prepackaged Bazel binary/executable. Bazel is currently
+  # only needed by `chromium/src/tools/rust/build_crubit.py` and therefore
+  # shouldn't be used outside of Chromium Rust Experiments project.
+  # Furthermore note that Bazel is only needed when building Crubit during Rust
+  # toolchain build (and is *not* needed during regular Chromium builds).
+  'checkout_bazel': False,
+
+  # Fetch Crubit support libraries in order to build ..._rs_api.rs and
+  # ..._rs_api_impl.cc that are generated by prebuilt (see
+  # tools/rust/build_crubit.py) Crubit tools during Chromium build (see
+  # also //build/rust/rs_bindings_from_cc.gni).
+  'checkout_crubit': 'use_rust',
+
   # By default checkout the OpenXR loader library only on Windows. The OpenXR
   # backend for VR in Chromium is currently only supported for Windows, but
   # support for other platforms may be added in the future.
@@ -184,6 +197,12 @@ vars = {
   # qemu on linux-arm64 machines.
   'checkout_fuchsia_for_arm64_host': False,
 
+  # Revision of Crubit (trunk on 2022-07-14).  This should typically be the
+  # same as the revision specified in CRUBIT_REVISION in
+  # tools/rust/update_rust.py.  More details and roll instructions can be
+  # found in tools/rust/README.md.
+  'crubit_revision': 'd9b0ad4c09b46328dcc7a5ec28ce86cca56e0389',
+
   # Run 'vpython_common' hook if this is set.
   # TODO(crbug.com/1329052): remove this when we remove .vpython.
   'enable_vpython_common_crbug_1329052': True,
@@ -214,7 +233,7 @@ vars = {
   #
   # CQ_INCLUDE_TRYBOTS=luci.chrome.try:lacros-amd64-generic-chrome-skylab
   # CQ_INCLUDE_TRYBOTS=luci.chrome.try:lacros-arm-generic-chrome-skylab
-  'lacros_sdk_version': '14844.0.0',
+  'lacros_sdk_version': '14977.0.0',
 
   # Generate location tag metadata to include in tests result data uploaded
   # to ResultDB. This isn't needed on some configs and the tool that generates
@@ -226,7 +245,7 @@ vars = {
   # luci-go CIPD package version.
   # Make sure the revision is uploaded by infra-packagers builder.
   # https://ci.chromium.org/p/infra-internal/g/infra-packagers/console
-  'luci_go': 'git_revision:de014227dd270df7c61bfab740eb4ae4b52ac2a7',
+  'luci_go': 'git_revision:a0ba80649473055bae3d789eec28c9967adb5e45',
 
   # This can be overridden, e.g. with custom_vars, to build clang from HEAD
   # instead of downloading the prebuilt pinned revision.
@@ -250,6 +269,9 @@ vars = {
   # for info on RTS
   'checkout_rts_model': False,
 
+  # Use the experimental version of the RTS model
+  'checkout_rts_experimental_model': False,
+
   # By default, do not check out the re-client binaries.
   'checkout_reclient': False,
 
@@ -257,7 +279,7 @@ vars = {
   'dawn_standalone': False,
 
   # reclient CIPD package version
-  'reclient_version': 're_client_version:0.68.0.2c94334-gomaip',
+  'reclient_version': 're_client_version:0.72.0.b874055-gomaip',
 
   # Enable fetching Rust-related packages.
   'use_rust': False,
@@ -275,34 +297,34 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
-  'skia_revision': '5a4dbb2e97302f7e574f0ba962ac4d8b3a62a36e',
+  'skia_revision': 'f204b137b97b44b7397de173fc54181c37ac6501',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.
-  'v8_revision': '3d67ad243ce92b9fb162cc85da1dc1a0ebe4c78b',
+  'v8_revision': 'b1f56b4a8a7cf9f707f7966104278777f9994b13',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
-  'angle_revision': '2693b03eba82a424a19febaacaab4115a45b7682',
+  'angle_revision': '2f0d8ab049b10ee41f9b90cea8da8e80db076e38',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.
-  'swiftshader_revision': 'd68d367047f562e0e0716fd72b9a2bc3e2c8f4c0',
+  'swiftshader_revision': '16e026a959f1bc80ff237aa81b4a63b52517dec1',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling PDFium
   # and whatever else without interference from each other.
-  'pdfium_revision': 'c7c276ce1192f043affb2098ac7ce44f7fd7f084',
+  'pdfium_revision': 'd14da8e682e244127db32490365d1c094243e5f3',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling BoringSSL
   # and whatever else without interference from each other.
   #
   # Note this revision should be updated with
   # third_party/boringssl/roll_boringssl.py, not roll-dep.
-  'boringssl_revision': '1e469e45a46ff580899cbef939babe02ad916c85',
+  'boringssl_revision': 'b95124305ab15c7523d3e21437309fa5dd717ee8',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Fuchsia sdk
   # and whatever else without interference from each other.
-  'fuchsia_version': 'version:8.20220609.0.1',
+  'fuchsia_version': 'version:9.20220720.2.1',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling google-toolbox-for-mac
   # and whatever else without interference from each other.
@@ -318,23 +340,23 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling lss
   # and whatever else without interference from each other.
-  'lss_revision': '1d387f43f3702818f7fc04d334539a2f05cafccd',
+  'lss_revision': '0d6435b731ef91d5182eaecff82ae96764222c48',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling NaCl
   # and whatever else without interference from each other.
-  'nacl_revision': '77f46a8ec552f316f64aaa82b7f06da9fceb036b',
+  'nacl_revision': '18d9964d47fc44f49a4c19b7ba91197ddca00c6a',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling freetype
   # and whatever else without interference from each other.
-  'freetype_revision': 'b11074cf6dce78d0bc79ff7996dec70ca3abe4a9',
+  'freetype_revision': '275b116b40c9d183d42242099ea9ff276985855b',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling freetype
   # and whatever else without interference from each other.
-  'freetype_testing_revision': 'fe2eddae6176f75e2101289eeda22a5ff3d808ca',
+  'freetype_testing_revision': '1ca0c99d25ae3b1e4c70513c1bf74643fc3dee09',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling HarfBuzz
   # and whatever else without interference from each other.
-  'harfbuzz_revision': 'c88a6a9ec3c38793ec8b662362282e076e948943',
+  'harfbuzz_revision': 'fa471043fccb94444510e3300ac2573297c82137',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Emoji Segmenter
   # and whatever else without interference from each other.
@@ -342,11 +364,11 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling OTS
   # and whatever else without interference from each other.
-  'ots_revision': 'ee537ac096667eed6559124164c3e8482646fd77',
+  'ots_revision': '46bea9879127d0ff1c6601b078e2ce98e83fcd33',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling catapult
   # and whatever else without interference from each other.
-  'catapult_revision': '8a8c0b9c3967e17da1d9f64b3d57e4a969b465a7',
+  'catapult_revision': 'b6e934ef32e6591ad60636e3fe167d0e3e9aa5d4',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling libFuzzer
   # and whatever else without interference from each other.
@@ -354,11 +376,11 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling devtools-frontend
   # and whatever else without interference from each other.
-  'devtools_frontend_revision': 'ed8fe6a3c528058bcc8e95b9071be6d6cb1b45f2',
+  'devtools_frontend_revision': 'b1ac4239dc5fffa56170e7367a03f35d2eaa223c',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling libprotobuf-mutator
   # and whatever else without interference from each other.
-  'libprotobuf-mutator': '8942a9ba43d8bb196230c321d46d6a137957a719',
+  'libprotobuf-mutator': 'a304ec48dcf15d942607032151f7e9ee504b5dcf',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling android_sdk_build-tools_version
   # and whatever else without interference from each other.
@@ -390,11 +412,11 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'dawn_revision': '2d334ed4f01b00211acd0360a5f9dc91d83354cb',
+  'dawn_revision': '1e98a9ba4a64301e0ab932e22ce989688f6cdf6c',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'quiche_revision': '26920de2d369289246585fa1b236ef2ef516d317',
+  'quiche_revision': '53c94d968dd6a0cf748caf42462a0b676f95530c',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ios_webkit
   # and whatever else without interference from each other.
@@ -406,7 +428,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling wuffs
   # and whatever else without interference from each other.
-  'wuffs_revision': 'ebbecaa2fb439eff0aeedafadb4c2a984446dee8',
+  'wuffs_revision': 'a8205c2fe7564b12fea81ee028ba670112cc7719',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling libgifcodec
   # and whatever else without interference from each other.
@@ -414,11 +436,11 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling libavif
   # and whatever else without interference from each other.
-  'libavif_revision': '1dedea43710c55a1bf1c675126cb6cb546c7b2a7',
+  'libavif_revision': 'dd2d67c5f976038354c0406a253e26dd2abc4632',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling nearby
   # and whatever else without interference from each other.
-  'nearby_revision': 'd8453565db739ebbfbbeade9ec8f8239057b1e13',
+  'nearby_revision': 'd2c401112cc577fe3c5f9a11329bb557048af31a',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling securemessage
   # and whatever else without interference from each other.
@@ -434,15 +456,15 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'libcxxabi_revision':    '013bcd820a353ec1d3ff472f2971553fea7232cf',
+  'libcxxabi_revision':    'b954e3e65634a9e2f7b595598a30c455f5f2eb26',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'libunwind_revision':    '1644d070bf374182739543c3a12df88dfec0b88a',
+  'libunwind_revision':    '955e2ff5fbb15791fea263c1c80e1ec6b3c5ee61',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'clang_format_revision':    'e435ad79c17b1888b34df88d6a30a094936e3836',
+  'clang_format_revision':    '8b525d2747f2584fc35d8c7e612e66f377858df7',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
@@ -451,13 +473,17 @@ vars = {
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
   'highway_revision': '424360251cdcfc314cfc528f53c872ecd63af0f0',
+  # Three lines of non-changing comments so that
+  # the commit queue can handle CLs rolling ffmpeg
+  # and whatever else without interference from each other.
+  'ffmpeg_revision': '880df5ede50a8534c8116d0d50e4bc4f3ef08a06',
 
   # If you change this, also update the libc++ revision in
   # //buildtools/deps_revisions.gni.
-  'libcxx_revision':       'b1269813eaf5b8ac78e35e45a0f7cc320bd3e7d6',
+  'libcxx_revision':       '88bf4070487fbe9020697a2281743b91e5e29bef',
 
   # GN CIPD package version.
-  'gn_version': 'git_revision:2ecd43a10266bd091c98e6dcde507c64f6a0dad3',
+  'gn_version': 'git_revision:9ef321772ecc161937db69acb346397e0ccc484d',
 }
 
 # Only these hosts are allowed for dependencies in this DEPS file.
@@ -538,7 +564,7 @@ deps = {
     'packages': [
       {
         'package': 'chromium/third_party/android_rust_toolchain/linux-amd64',
-        'version': 'BKAbvHjGv4-os-v8MS3I54bPsY-397xgaJ3yBeIVS20C',
+        'version': 'rMU9JFlwRfB-5VEWgDPRFYme5sXSnsHPSE3uQXf1xBQC',
       },
     ],
     'dep_type': 'cipd',
@@ -608,7 +634,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chrome_mac_universal',
-          'version': '3UoNd4X57YAONz6mhQPapIUoO1Ds6K5AIHTAZxNmLUUC',
+          'version': 'RBRqNIwSXHjdZf4BVjWk8enaKIHw58aQGFDVNozlbWIC',
         },
       ],
   },
@@ -619,7 +645,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chrome_win_x86',
-          'version': 'vTjr7sgsZvG680Qx0nhiR3H4-EAJDdh5m1BkVbbuER0C',
+          'version': 'tqlS-vFYsn2LVSJMwipq84EKLmwKa1XJb760NnpQL2gC',
         },
       ],
   },
@@ -630,7 +656,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chrome_win_x86_64',
-          'version': 'dQu9E9-wPljBkp6aaMxzCt9WJdBI_u_w2N1VRS2Mdf4C',
+          'version': 'RthX5RzppvSV7uq2P6pm2bnv6-dvoHpUIOsZFk57ZMEC',
         },
       ],
   },
@@ -642,7 +668,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chromium_mac_amd64',
-          'version': '1RmnK4JbmordT5NJbib3mfagpHvrO-oJaTW4HKsYgmAC',
+          'version': '7MvxvS-pmZP1iAXQoCiLI7nv4UkDiyw8PC1ycwpYWbYC',
         },
       ],
   },
@@ -654,7 +680,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chromium_mac_arm64',
-          'version': '-o_WPHLr3JzvHdsTl_E0AgEV2D2--sBNqVT_F74hvOIC',
+          'version': 'd5lN7fzV07O4-Mu_T8TshrGQtlR9F508p9cdhchcLpYC',
         },
       ],
   },
@@ -665,7 +691,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chromium_win_x86',
-          'version': 'zdcQMuiuIXnQQ4eBsYyk0uNTr4N0LaphcQYs0RUByZQC',
+          'version': '8zehx-DVmaf_FplPe23acLAStf3Z7anQ3CY9LXBfvD0C',
         },
       ],
   },
@@ -676,7 +702,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/updater/chromium_win_x86_64',
-          'version': '77COFCYoGCHrnvDJZFC8GoYea4B8GeTVWNKpUZBCwe4C',
+          'version': 'KE8JnjZFOyHxUhVdRkm0IMVqlZIaYPnAOI-zxtUD4zUC',
         },
       ],
   },
@@ -747,16 +773,16 @@ deps = {
     Var('chromium_git') + '/external/github.com/toji/webvr.info.git' + '@' + 'c58ae99b9ff9e2aa4c524633519570bf33536248',
 
   'src/docs/website': {
-    'url': Var('chromium_git') + '/website.git' + '@' + 'ffb0b23dc2833849a0b1e57f25caba219e717963',
+    'url': Var('chromium_git') + '/website.git' + '@' + '3965ba67f8d283378e6c0b64d634b91fb830a378',
   },
 
   'src/ios/third_party/earl_grey2/src': {
-      'url': Var('chromium_git') + '/external/github.com/google/EarlGrey.git' + '@' + '16126e61e3b831b005a91d83cecefd54628530bb',
+      'url': Var('chromium_git') + '/external/github.com/google/EarlGrey.git' + '@' + '53a2982c85ac6cf802719603d037ad3be7091ebb',
       'condition': 'checkout_ios',
   },
 
   'src/ios/third_party/edo/src': {
-      'url': Var('chromium_git') + '/external/github.com/google/eDistantObject.git' + '@' + '07ef2f35406e9f04cf86d11da5cc62d58f36cb15',
+      'url': Var('chromium_git') + '/external/github.com/google/eDistantObject.git' + '@' + '3d3dcee71993376f3abcf3457b046c1df6c13182',
       'condition': 'checkout_ios',
   },
 
@@ -765,13 +791,8 @@ deps = {
       'condition': 'checkout_ios',
   },
 
-  'src/ios/third_party/gcdwebserver/src': {
-      'url': Var('chromium_git') + '/external/github.com/swisspol/GCDWebServer.git' + '@' + '43555c66627f6ed44817855a0f6d465f559d30e0',
-      'condition': 'checkout_ios',
-  },
-
   'src/ios/third_party/material_components_ios/src': {
-      'url': Var('chromium_git') + '/external/github.com/material-components/material-components-ios.git' + '@' + '8225446a8df15e53e96304852f134259e0e5e2df',
+      'url': Var('chromium_git') + '/external/github.com/material-components/material-components-ios.git' + '@' + '425d641798c86ab809fcb067bbb265958756af98',
       'condition': 'checkout_ios',
   },
 
@@ -796,7 +817,7 @@ deps = {
   },
 
   'src/ios/third_party/material_text_accessibility_ios/src': {
-      'url': Var('chromium_git') + '/external/github.com/material-foundation/material-text-accessibility-ios.git' + '@' + '197375261e25ee5d473219d0f353a1f635f5393d',
+      'url': Var('chromium_git') + '/external/github.com/material-foundation/material-text-accessibility-ios.git' + '@' + '8cd910c1c8bbae261ae0d7e873ed96c69a386448',
       'condition': 'checkout_ios',
   },
 
@@ -841,7 +862,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/rts/model/linux-amd64',
-          'version': 'gpPYMz2bs2vn_NVI9vEIw6a1w2oQ7ck6CsoRISA8fgoC',
+          'version': 'XlzIsX8AH06QHVAMzpKt5aT3nfupjnBr78ztG18pXdsC',
         },
       ],
       'dep_type': 'cipd',
@@ -852,7 +873,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/rts/model/mac-amd64',
-          'version': 'swy7IasO6Zn8zMTIWXP3ixCvml7S_2vUby60ZuPlFdEC',
+          'version': 'CPhzNoasDtJ45F8bwTLs7lIQDiy-PhdReFmXrlL5FDoC',
         },
       ],
       'dep_type': 'cipd',
@@ -863,13 +884,24 @@ deps = {
       'packages': [
         {
           'package': 'chromium/rts/model/windows-amd64',
-          'version': 'eIvALKHzZkCX0uLI5LLb8fpo2ckXFiu_dh4_8SdQyE8C',
+          'version': 'XmZtpYZGxTqwBMgEXpdyfrdCxx79QfYeVlhpviF2OUcC',
         },
       ],
       'dep_type': 'cipd',
       'condition': 'checkout_rts_model and checkout_win',
   },
 
+  'src/testing/rts/rts-ml-chromium/linux-amd64': {
+      'packages': [
+        {
+          'package': 'experimental/google.com/sshrimp/chromium/rts/model/linux-amd64',
+          'version': '3K1dz8hGV_xBeEcPKmXfrPYWCwXdRf6KVVLrg7AuJ0sC',
+        },
+      ],
+      'dep_type': 'cipd',
+      'condition': 'checkout_rts_experimental_model and checkout_linux',
+  },
+
   'src/tools/luci-go': {
       'packages': [
         {
@@ -920,7 +952,7 @@ deps = {
     'packages': [
       {
           'package': 'chromium/third_party/androidx',
-          'version': 'rMO5RMLXC5cyz-Lk9zE9bV66Gc8ggeO7EPkCxYXNO2oC',
+          'version': 'gAsD4l8EoP_W0IH5vzedZ1tyN3-wAP8-fqkaS_mX6rcC',
       },
     ],
     'condition': 'checkout_android',
@@ -953,7 +985,7 @@ deps = {
       'packages': [
           {
               'package': 'chromium/third_party/android_build_tools/aapt2',
-              'version': 'jziPmg_EUjoj-eSkO24eMaf5ylm449Q7BKO1-ga2tbgC',
+              'version': 'hf9C5IyJUUGaBnzqu60xiFJSyfAmjqjc_PiNXNVc9l0C',
           },
       ],
       'condition': 'checkout_android',
@@ -964,7 +996,29 @@ deps = {
       'packages': [
           {
                'package': 'chromium/third_party/android_build_tools/bundletool',
-               'version': 'AqsPZpWJh-ZyGraHKlbH8XgjRnmyDmolX4HhwPEo9XUC',
+               'version': 'qLkNwA6wjoqznVqaa151GelgGBP4X495n0z-jluACPcC',
+          },
+      ],
+      'condition': 'checkout_android',
+      'dep_type': 'cipd',
+  },
+
+  'src/third_party/android_build_tools/lint': {
+      'packages': [
+          {
+               'package': 'chromium/third_party/android_build_tools/lint',
+               'version': 'INnGGTfg5gGJutJiBtWI6-QwusHDDnKvZzI53Q3UiecC',
+          },
+      ],
+      'condition': 'checkout_android',
+      'dep_type': 'cipd',
+  },
+
+  'src/third_party/android_build_tools/manifest_merger': {
+      'packages': [
+          {
+               'package': 'chromium/third_party/android_build_tools/manifest_merger',
+               'version': '0WkAedh1tJB8lzisWJRT80UjpacKLltuV7NqP-0tx9gC',
           },
       ],
       'condition': 'checkout_android',
@@ -1004,7 +1058,7 @@ deps = {
           },
           {
               'package': 'chromium/third_party/android_sdk/public/cmdline-tools',
-              'version': 'PGPmqJtSIQ84If155ba7iTU846h5WJ-bL5d_OoUWEWYC',
+              'version': 'IPzAG-uU5zVMxohpg9-7-N0tQC1TCSW1VbrBFw7Ld04C',
           },
       ],
       'condition': 'checkout_android_native_support',
@@ -1015,7 +1069,7 @@ deps = {
     Var('chromium_git') + '/angle/angle.git' + '@' +  Var('angle_revision'),
 
   'src/third_party/content_analysis_sdk/src':
-    Var('chromium_git') + '/external/github.com/chromium/content_analysis_sdk.git' + '@' + 'd2a0b6188bcbae674f8ef2c42c7cffc908ac632e',
+    Var('chromium_git') + '/external/github.com/chromium/content_analysis_sdk.git' + '@' + '1d7dd0490808a8a972949521cc314e42d085c69f',
 
   'src/third_party/dav1d/libdav1d':
     Var('chromium_git') + '/external/github.com/videolan/dav1d.git' + '@' + '87f9a81cd770e49394a45deca7a3df41243de00b',
@@ -1047,17 +1101,6 @@ deps = {
   'src/third_party/boringssl/src':
     Var('boringssl_git') + '/boringssl.git' + '@' +  Var('boringssl_revision'),
 
-  'src/third_party/bouncycastle': {
-      'packages': [
-          {
-              'package': 'chromium/third_party/bouncycastle',
-              'version': 'c078e87552ba26e776566fdaf0f22cd8712743d0',
-          },
-      ],
-      'condition': 'checkout_android',
-      'dep_type': 'cipd',
-  },
-
   'src/third_party/breakpad/breakpad':
     Var('chromium_git') + '/breakpad/breakpad.git' + '@' + 'c4c43b80ea8854c57a4374ac32579b577172dc23',
 
@@ -1084,7 +1127,7 @@ deps = {
   },
 
   'src/third_party/cast_core/public/src':
-    Var('chromium_git') + '/cast_core/public' + '@' + '6c053df4fe5aea168ca651e2d95dc5dc40ebe059',
+    Var('chromium_git') + '/cast_core/public' + '@' + '8ba5ff47563d0ca8233e8fa009377ed14a560cf4',
 
   'src/third_party/catapult':
     Var('chromium_git') + '/catapult.git' + '@' + Var('catapult_revision'),
@@ -1113,7 +1156,7 @@ deps = {
   # Tools used when building Chrome for Chrome OS. This affects both the Simple
   # Chrome workflow, as well as the chromeos-chrome ebuild.
   'src/third_party/chromite': {
-      'url': Var('chromium_git') + '/chromiumos/chromite.git' + '@' + '41d2e02e8d1438445eee7463ae4536fe6280e0fc',
+      'url': Var('chromium_git') + '/chromiumos/chromite.git' + '@' + '60350fcfeb0bca00eba2794f53661a1b996a79a5',
       'condition': 'checkout_chromeos',
   },
 
@@ -1131,12 +1174,17 @@ deps = {
 
   # For Linux and Chromium OS.
   'src/third_party/cros_system_api': {
-      'url': Var('chromium_git') + '/chromiumos/platform2/system_api.git' + '@' + '315a946dfdf2b0d850e35ec2dbca7ad45525c6ff',
+      'url': Var('chromium_git') + '/chromiumos/platform2/system_api.git' + '@' + 'f3b1373caf7bd717be4f0d21ab8c738c6bfcf418',
       'condition': 'checkout_linux',
   },
 
+  'src/third_party/crubit/src': {
+      'url': Var('chromium_git') + '/external/github.com/google/crubit.git' + '@' + Var('crubit_revision'),
+      'condition': 'checkout_crubit',
+  },
+
   'src/third_party/depot_tools':
-    Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + 'a4b3602457c422f8ed054ff3673baaecedc2972a',
+    Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + '0ba2fd429dd6db431fcbee6995c1278d2a3657a0',
 
   'src/third_party/devtools-frontend/src':
     Var('chromium_git') + '/devtools/devtools-frontend' + '@' + Var('devtools_frontend_revision'),
@@ -1145,7 +1193,7 @@ deps = {
     Var('chromium_git') + '/chromium/dom-distiller/dist.git' + '@' + '199de96b345ada7c6e7e6ba3d2fa7a6911b8767d',
 
   'src/third_party/eigen3/src':
-    Var('chromium_git') + '/external/gitlab.com/libeigen/eigen.git' + '@' + 'b02c384ef4e8eba7b8bdef16f9dc6f8f4d6a6b2b',
+    Var('chromium_git') + '/external/gitlab.com/libeigen/eigen.git' + '@' + '0e187141679fdb91da33249d18cb79a011c0e2ea',
 
   'src/third_party/emoji-metadata/src': {
     'url': Var('chromium_git') + '/external/github.com/googlefonts/emoji-metadata' + '@' + '8de89a7a36cd024dcd30ac9f67f3f02c37a7c8fb',
@@ -1167,13 +1215,13 @@ deps = {
     Var('chromium_git') + '/external/github.com/google/farmhash.git' + '@' + '816a4ae622e964763ca0862d9dbd19324a1eaf45',
 
   'src/third_party/ffmpeg':
-    Var('chromium_git') + '/chromium/third_party/ffmpeg.git' + '@' + 'abfc2628f25d283c27ffc960a8ff820ae8110467',
+    Var('chromium_git') + '/chromium/third_party/ffmpeg.git' + '@' + Var('ffmpeg_revision'),
 
   'src/third_party/flac':
     Var('chromium_git') + '/chromium/deps/flac.git' + '@' + 'af862024c8c8fa0ae07ced05e89013d881b00596',
 
   'src/third_party/flatbuffers/src':
-    Var('chromium_git') + '/external/github.com/google/flatbuffers.git' + '@' + 'b8aaccee8248059b2af032cca0eb1d2ddbdb6cdc',
+    Var('chromium_git') + '/external/github.com/google/flatbuffers.git' + '@' + '0fe13cb28ce5a3fb81f654b21cb37c9821194962',
 
   # Used for embedded builds. CrOS & Linux use the system version.
   'src/third_party/fontconfig/src': {
@@ -1188,7 +1236,7 @@ deps = {
     Var('chromium_git') + '/external/github.com/google/gemmlowp.git' + '@' + '13d57703abca3005d97b19df1f2db731607a7dc2',
 
   'src/third_party/grpc/src': {
-      'url': Var('chromium_git') + '/external/github.com/grpc/grpc.git' + '@' + 'd1338d8751231bdc0d87e732d25420e87d24cffd',
+      'url': Var('chromium_git') + '/external/github.com/grpc/grpc.git' + '@' + '89f7534e43cf73f56c492a9cf7eb85ca6bfbd87a',
   },
 
   'src/third_party/freetype/src':
@@ -1210,7 +1258,7 @@ deps = {
     Var('chromium_git') + '/external/github.com/khaledhosny/ots.git' + '@' + Var('ots_revision'),
 
   'src/third_party/libgav1/src':
-    Var('chromium_git') + '/codecs/libgav1.git' + '@' + '38ca0c62d9079820bbb872d81738770c0a28ae6d',
+    Var('chromium_git') + '/codecs/libgav1.git' + '@' + 'cd53f7c0d6a1c005e38874d143c8876d375bae70',
 
   'src/third_party/google_toolbox_for_mac/src': {
       'url': Var('chromium_git') + '/external/github.com/google/google-toolbox-for-mac.git' + '@' + Var('google_toolbox_for_mac_revision'),
@@ -1248,7 +1296,7 @@ deps = {
   },
 
   'src/third_party/arcore-android-sdk/src': {
-      'url': Var('chromium_git') + '/external/github.com/google-ar/arcore-android-sdk.git' + '@' + 'eaa85941f2d724c60671bf94f46de7178baba7e6',
+      'url': Var('chromium_git') + '/external/github.com/google-ar/arcore-android-sdk.git' + '@' + 'd197af6b38f98d2344bc7f76326c4aa0c4f2fb90',
       'condition': 'checkout_android',
   },
 
@@ -1256,7 +1304,7 @@ deps = {
       'packages': [
         {
           'package': 'chromium/third_party/arcore-android-sdk-client',
-          'version': 'fUSZ4jxIhIx34TxRIcrmOu76-khcka_Gpn0_t9lKCWQC',
+          'version': 'NYf1qvBS9hNVK-6exAl-MaVbQsRKCDYl5Br936GtcU0C',
         },
       ],
 
@@ -1290,7 +1338,7 @@ deps = {
     Var('chromium_git') + '/chromium/deps/hunspell_dictionaries.git' + '@' + '41cdffd71c9948f63c7ad36e1fb0ff519aa7a37e',
 
   'src/third_party/icu':
-    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + '12de966fcbe1d1a48dba310aee63807856ffeee8',
+    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + '6e558942cc8b83e525bdabaf987e06af8a377314',
 
   'src/third_party/icu4j': {
       'packages': [
@@ -1358,10 +1406,10 @@ deps = {
     Var('chromium_git') + '/chromium/llvm-project/compiler-rt/lib/fuzzer.git' + '@' +  Var('libfuzzer_revision'),
 
   'src/third_party/libaddressinput/src':
-    Var('chromium_git') + '/external/libaddressinput.git' + '@' + 'a56be6f77ea76a9e77561ca306acede244631610',
+    Var('chromium_git') + '/external/libaddressinput.git' + '@' + 'df35d6c42da4fa2759e4cfb592afe33817993b89',
 
   'src/third_party/libaom/source/libaom':
-    Var('aomedia_git') + '/aom.git' + '@' +  '32d6783c4c9f6e78f43bd4ceffaa0eb2143aed57',
+    Var('aomedia_git') + '/aom.git' + '@' +  '8dcdafc6d4a2f9f8ea8104f26eca5d123eefcb7f',
 
   'src/third_party/libavif/src':
     Var('chromium_git') + '/external/github.com/AOMediaCodec/libavif.git' + '@' + Var('libavif_revision'),
@@ -1394,7 +1442,7 @@ deps = {
     Var('chromium_git') + '/chromium/deps/libjpeg_turbo.git' + '@' + '22f1a22c99e9dde8cd3c72ead333f425c5a7aa77',
 
   'src/third_party/liblouis/src': {
-      'url': Var('chromium_git') + '/external/liblouis-github.git' + '@' + 'c05f3bfb0990434bd12bf6697d16ed943f2203c2',
+      'url': Var('chromium_git') + '/external/liblouis-github.git' + '@' + '9700847afb92cb35969bdfcbbfbbb74b9c7b3376',
       'condition': 'checkout_linux',
   },
 
@@ -1419,13 +1467,16 @@ deps = {
   },
 
   'src/third_party/libvpx/source/libvpx':
-    Var('chromium_git') + '/webm/libvpx.git' + '@' +  'ca89bed50dbc5fe2abef50c5f36924bb1da6d1f6',
+    Var('chromium_git') + '/webm/libvpx.git' + '@' +  '711bef67400f096416cb1ba7f6560e533871490f',
 
   'src/third_party/libwebm/source':
     Var('chromium_git') + '/webm/libwebm.git' + '@' + 'e4fbea0c9751ae8aa86629b197a28d8276a2b0da',
 
+  'src/third_party/libwebp/src':
+    Var('chromium_git') + '/webm/libwebp.git' + '@' +  '7366f7f394af26de814296152c50e673ed0a832f',
+
   'src/third_party/libyuv':
-    Var('chromium_git') + '/libyuv/libyuv.git' + '@' + '30f9b280487be412da346aecce7834275020976e',
+    Var('chromium_git') + '/libyuv/libyuv.git' + '@' + 'd248929c059ff7629a85333699717d7a677d8d96',
 
   'src/third_party/lighttpd': {
       'url': Var('chromium_git') + '/chromium/deps/lighttpd.git' + '@' + Var('lighttpd_revision'),
@@ -1516,7 +1567,7 @@ deps = {
     Var('chromium_git') + '/external/github.com/cisco/openh264' + '@' + 'fac04ceb3e966f613ed17e98178e9d690280bba6',
 
   'src/third_party/openscreen/src':
-    Var('chromium_git') + '/openscreen' + '@' + '1ea464c1b10821e39dd487b6f9e4813c5c8546b0',
+    Var('chromium_git') + '/openscreen' + '@' + '6be6b78224a276e908b8272542d125e133c40f3f',
 
   'src/third_party/openxr/src': {
     'url': Var('chromium_git') + '/external/github.com/KhronosGroup/OpenXR-SDK' + '@' + 'bf21ccb1007bb531b45d9978919a56ea5059c245',
@@ -1533,7 +1584,7 @@ deps = {
   },
 
   'src/third_party/perfetto':
-    Var('android_git') + '/platform/external/perfetto.git' + '@' + 'a6b4d9563ec37e531ebcc21912c3078ba4c2b367',
+    Var('android_git') + '/platform/external/perfetto.git' + '@' + '361efbf9aab595e4dfa79ec48f242d9e722393c9',
 
   'src/third_party/perl': {
       'url': Var('chromium_git') + '/chromium/deps/perl.git' + '@' + '6f3e5028eb65d0b4c5fdd792106ac4c84eee1eb3',
@@ -1569,8 +1620,8 @@ deps = {
   'src/third_party/qemu-linux-arm64': {
       'packages': [
           {
-              'package': 'fuchsia/qemu/linux-arm64',
+              'package': 'fuchsia/third_party/qemu/linux-arm64',
-              'version': 'b1b61a39e3ab0935cd030f27e01740578b04b967'
+              'version': 'BpnoBb2d44_SOm9toN6Lju5a2RLGAc1TPUO6xyijoP8C'
           },
       ],
       'condition': 'host_os == "linux" and checkout_fuchsia and checkout_fuchsia_for_arm64_host',
@@ -1584,7 +1635,7 @@ deps = {
       'packages': [
           {
               'package': 'chromium/third_party/r8',
-              'version': 'iMLEt10uXASDfG2AlATR1fO8xYhBoF24nQvDDXLY6Q8C',
+              'version': 'auReXfxxD74XGdPdi-rYsKrp4sRwYwgNjh_W0PT7vNcC',
           },
       ],
       'condition': 'checkout_android',
@@ -1608,7 +1659,7 @@ deps = {
   },
 
   'src/third_party/ruy/src':
-    Var('chromium_git') + '/external/github.com/google/ruy.git' + '@' + '7ef39c5745a61f43071e699c6a96da41701ae59f',
+    Var('chromium_git') + '/external/github.com/google/ruy.git' + '@' + '72155b3185246e9143f4c6a3a7f283d2ebba8524',
 
   'src/third_party/skia':
     Var('skia_git') + '/skia.git' + '@' +  Var('skia_revision'),
@@ -1620,7 +1671,7 @@ deps = {
     Var('chromium_git') + '/external/github.com/google/snappy.git' + '@' + '65dc7b383985eb4f63cd3e752136db8d9b4be8c0',
 
   'src/third_party/sqlite/src':
-    Var('chromium_git') + '/chromium/deps/sqlite.git' + '@' + 'cb47d7089f714e4514f126dfa8ac630cab78ea32',
+    Var('chromium_git') + '/chromium/deps/sqlite.git' + '@' + 'e6b63421941617bf5ccac6b4a62d7a7b4a2c3fef',
 
   'src/third_party/sqlite4java': {
       'packages': [
@@ -1651,25 +1702,20 @@ deps = {
     Var('chromium_git') + '/external/github.com/GoogleChromeLabs/text-fragments-polyfill.git' + '@' + 'c036420683f672d685e27415de0a5f5e85bdc23f',
 
   'src/third_party/tflite/src':
-    Var('chromium_git') + '/external/github.com/tensorflow/tensorflow.git' + '@' + '5ddefa9f8d1455c8ca694ba1a511ba82e3a88960',
+    Var('chromium_git') + '/external/github.com/tensorflow/tensorflow.git' + '@' + 'ac31ffa987c14665062c00f98ec025a3fdc185ab',
 
   'src/third_party/turbine': {
       'packages': [
           {
               'package': 'chromium/third_party/turbine',
-              'version': 'A5bkaoLBc1JYa6Xv31jYUCK5TnXYCbxRrA4FBPXXcWgC',
+              'version': 'RxaW8ZVJZ7rF3dbAGbL1OV6f9ZELjVeiiQbpkDsuxA4C',
           },
       ],
       'condition': 'checkout_android',
       'dep_type': 'cipd',
   },
 
-  'src/third_party/ub-uiautomator/lib': {
+  'src/third_party/vulkan-deps': '{chromium_git}/vulkan-deps@c42337d9ef75170244486b580bad7dfe78447bfd',
-      'url': Var('chromium_git') + '/chromium/third_party/ub-uiautomator.git' + '@' + '00270549ce3161ae72ceb24712618ea28b4f9434',
-      'condition': 'checkout_android',
-  },
-
-  'src/third_party/vulkan-deps': '{chromium_git}/vulkan-deps@12989fc8d7d273b5b95ef988d37469738eb9c39b',
 
   'src/third_party/vulkan_memory_allocator':
     Var('chromium_git') + '/external/github.com/GPUOpen-LibrariesAndSDKs/VulkanMemoryAllocator.git' + '@' + 'ebe84bec02c041d28f902da0214bf442743fc907',
@@ -1702,13 +1748,13 @@ deps = {
     Var('chromium_git') + '/external/github.com/SeleniumHQ/selenium/py.git' + '@' + 'd0045ec570c1a77612db35d1e92f05e1d27b4d53',
 
   'src/third_party/webgl/src':
-    Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + 'bb289ce3cb15bbabd42fdcb01439367846d9069d',
+    Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + '44e4c8770158c505b03ee7feafa4859d083b0912',
 
   'src/third_party/webgpu-cts/src':
-    Var('chromium_git') + '/external/github.com/gpuweb/cts.git' + '@' + '84183b561b7f44b2eae6a5f268d5085accb0ad7a',
+    Var('chromium_git') + '/external/github.com/gpuweb/cts.git' + '@' + 'c4eb1df3f306c0ee3e43ba2446eb3616e42d6855',
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + '06aea31d10f860ae4236e3422252557762d39188',
+    Var('webrtc_git') + '/src.git' + '@' + 'dc5cf31cad576376abd3aa6306169453cfd85ba5',
 
   'src/third_party/libgifcodec':
      Var('skia_git') + '/libgifcodec' + '@'+  Var('libgifcodec_revision'),
@@ -1729,7 +1775,7 @@ deps = {
   },
 
   'src/third_party/xnnpack/src':
-    Var('chromium_git') + '/external/github.com/google/XNNPACK.git' + '@' + 'da533e0114f2bf730f17853ae10556d84a3d1e89',
+    Var('chromium_git') + '/external/github.com/google/XNNPACK.git' + '@' + 'a33b227047def29b79853ef688b6dda6c6fc5386',
 
   'src/tools/page_cycler/acid3':
     Var('chromium_git') + '/chromium/deps/acid3.git' + '@' + '6be0a66a1ebd7ebc5abc1b2f405a945f6d871521',
@@ -1738,7 +1784,7 @@ deps = {
       'packages': [
         {
           'package': 'skia/tools/goldctl/linux-amd64',
-          'version': 'l0eo0uR9oMGZFKDucYLGk3vdNGAunP4tGrDhIfzljdcC',
+          'version': 'BquSeorcTU84O2_A8IoWetGrcfLWxLfZCo9sve1Wt2IC',
         },
       ],
       'dep_type': 'cipd',
@@ -1748,7 +1794,7 @@ deps = {
       'packages': [
         {
           'package': 'skia/tools/goldctl/windows-amd64',
-          'version': '7YFnDYPdgUOTWkaZe19LzWhmwWBuVMM9Q02sTDQtlkgC',
+          'version': 'AOoQr1u4-cOIEYJDAgVxGWoTiPaRcjrSsjjAaB-u_ggC',
         },
       ],
       'dep_type': 'cipd',
@@ -1759,7 +1805,7 @@ deps = {
       'packages': [
         {
           'package': 'skia/tools/goldctl/mac-amd64',
-          'version': '4shFavk40_bOJI9zUzvH2PaMW7tHKuxeEN0zik75F7sC',
+          'version': '-t3YY_sZ-jtMAYZ2PlhjudFnEUgk4m-HjlIwSip4tOAC',
         },
       ],
       'dep_type': 'cipd',
@@ -1770,7 +1816,7 @@ deps = {
       'packages': [
         {
           'package': 'skia/tools/goldctl/mac-arm64',
-          'version': 'Ynx3axT8ZDN7Nl5pNwI5w8PCCt7jax5FGf8jcyjUzt4C',
+          'version': 'x_xKUnqrgizoTO8mxX4RkyhpQ-nUp_x_go9YH-tc--QC',
         },
       ],
       'dep_type': 'cipd',
@@ -1781,7 +1827,7 @@ deps = {
     Var('chromium_git') + '/v8/v8.git' + '@' +  Var('v8_revision'),
 
   'src-internal': {
-    'url': 'https://chrome-internal.googlesource.com/chrome/src-internal.git@4ff96f70fd1b507f17579577080637625e6e2ef8',
+    'url': 'https://chrome-internal.googlesource.com/chrome/src-internal.git@c29563eac12bc062b66805a4766673729ce7d4ef',
     'condition': 'checkout_src_internal',
   },
 
@@ -1800,7 +1846,7 @@ deps = {
     'packages': [
       {
         'package': 'chromeos_internal/apps/eche_app/app',
-        'version': '3AnrwGQwN1GPv9gbT4wn-9ScZNzXc5x6e68tt5yFI30C',
+        'version': 'PEjYa5GVISxpuqCZfq9pZ3QeSWhNtWSdQ6gmJ8bizQ0C',
       },
     ],
     'condition': 'checkout_chromeos and checkout_src_internal',
@@ -1811,7 +1857,7 @@ deps = {
     'packages': [
       {
         'package': 'chromeos_internal/apps/help_app/app',
-        'version': 'Vmw_AXRtISh_bHtp8evOfKkTHoF7PksGw7-UBEamlI0C',
+        'version': 'MqUROEBmHZCBRsEY3abQ7JOvoDr5wZ_MTK3vAN-901wC',
       },
     ],
     'condition': 'checkout_chromeos and checkout_src_internal',
@@ -1822,7 +1868,7 @@ deps = {
     'packages': [
       {
         'package': 'chromeos_internal/apps/media_app/app',
-        'version': 'XXOw6zqfIbq0PGDfk6FNetf4Bsym6nYVy42v7R5n2AoC',
+        'version': 'tV1aN61vvzGiDSJgQxN_namEG8pvO6RTuO-qbQMC51IC',
       },
     ],
     'condition': 'checkout_chromeos and checkout_src_internal',
@@ -1833,7 +1879,7 @@ deps = {
     'packages': [
       {
         'package': 'chromeos_internal/apps/projector_app/app',
-        'version': 'C5cTyNZYNM9JtGlk_csAXrSxTsH8Mk2vTIU2dEfjRskC',
+        'version': 'Eeqz2JXdGXA3-P7iu9xSzSc3iyUuAruoN1W3-FplxR4C',
       },
     ],
     'condition': 'checkout_chromeos and checkout_src_internal',
@@ -3160,6 +3206,17 @@ deps = {
       'dep_type': 'cipd',
   },
 
+  'src/third_party/android_deps/libs/org_bouncycastle_bcprov_jdk15on': {
+      'packages': [
+          {
+              'package': 'chromium/third_party/android_deps/libs/org_bouncycastle_bcprov_jdk15on',
+              'version': 'version:2@1.68.cr1',
+          },
+      ],
+      'condition': 'checkout_android',
+      'dep_type': 'cipd',
+  },
+
   'src/third_party/android_deps/libs/org_ccil_cowan_tagsoup_tagsoup': {
       'packages': [
           {
@@ -3252,7 +3309,7 @@ deps = {
       'packages': [
           {
               'package': 'chromium/third_party/android_deps/libs/org_jetbrains_kotlin_kotlin_stdlib',
-              'version': 'version:2@1.6.21.cr1',
+              'version': 'version:2@1.7.0.cr1',
           },
       ],
       'condition': 'checkout_android',
@@ -3263,7 +3320,7 @@ deps = {
       'packages': [
           {
               'package': 'chromium/third_party/android_deps/libs/org_jetbrains_kotlin_kotlin_stdlib_common',
-              'version': 'version:2@1.6.21.cr1',
+              'version': 'version:2@1.7.0.cr1',
           },
       ],
       'condition': 'checkout_android',
@@ -3567,6 +3624,15 @@ deps = {
       ],
       'dep_type': 'cipd',
   },
+
+  'src/tools/bazel': {
+    'packages': [{
+       'package': 'infra/3pp/tools/bazel_bootstrap/${{platform}}',
+       'version': 'version:2@5.2.0.1',
+    }],
+    'dep_type': 'cipd',
+    'condition': 'checkout_bazel',
+  },
 }
 
 
@@ -3600,6 +3666,7 @@ include_rules = [
   '-absl',
   '-third_party/abseil-cpp',
   '+third_party/abseil-cpp/absl/base/attributes.h',
+  "+third_party/abseil-cpp/absl/functional/function_ref.h",
   "+third_party/abseil-cpp/absl/numeric/int128.h",
   '+third_party/abseil-cpp/absl/types/optional.h',
   '+third_party/abseil-cpp/absl/types/variant.h',
@@ -3619,20 +3686,6 @@ skip_child_includes = [
 
 
 hooks = [
-  # Download and initialize "vpython" VirtualEnv environment packages for
-  # Python2. We do this before running any other hooks so that any other
-  # hooks that might use vpython don't trip over unexpected issues and
-  # don't run slower than they might otherwise need to.
-  {
-    'name': 'vpython_common',
-    'pattern': '.',
-    # TODO(https://crbug.com/1205263): Run this on mac/arm too once it works.
-    'condition': 'not (host_os == "mac" and host_cpu == "arm64") and enable_vpython_common_crbug_1329052',
-    'action': [ 'vpython',
-                '-vpython-spec', 'src/.vpython',
-                '-vpython-tool', 'install',
-    ],
-  },
   # Download and initialize "vpython" VirtualEnv environment packages for
   # Python3. We do this before running any other hooks so that any other
   # hooks that might use vpython don't trip over unexpected issues and
@@ -3889,6 +3942,14 @@ hooks = [
                '-s', 'src/third_party/skia',
                '--header', 'src/skia/ext/skia_commit_hash.h'],
   },
+  {
+    # Update dawn_version.h.
+    'name': 'lastchange_dawn',
+    'pattern': '.',
+    'action': ['python3', 'src/build/util/lastchange.py',
+               '-s', 'src/third_party/dawn',
+               '--revision', 'src/gpu/webgpu/DAWN_VERSION'],
+  },
   # Pull dsymutil binaries using checked-in hashes.
   {
     'name': 'dsymutil_mac_arm64',
@@ -4447,6 +4508,16 @@ hooks = [
     ],
   },
 
+  {
+    'name': 'Download Fuchsia SDK from GCS',
+    'pattern': '.',
+    'condition': 'checkout_fuchsia',
+    'action': [
+      'python3',
+      'src/build/fuchsia/override_sdk.py',
+    ],
+  },
+
   {
     'name': 'Download Fuchsia system images',
     'pattern': '.',
@@ -4683,6 +4754,17 @@ hooks = [
     ],
     'condition': 'generate_location_tags',
   },
+
+  {
+    # Clean up build dirs for crbug.com/1337238.
+    # After a libc++ roll and revert, .ninja_deps would get into a state
+    # that breaks Ninja on Windows.
+    # TODO(crbug.com/1337238): Remove in a month or so.
+    'name': 'del_ninja_deps_cache',
+    'pattern': '.',
+    'condition': 'host_os == "win"',
+    'action': ['python3', 'src/build/del_ninja_deps_cache.py'],
+  },
 ]
 
 # Add any corresponding DEPS files from this list to chromium.exclusions in

src/base/BUILD.gn

@@ -159,6 +159,13 @@ buildflag_header("ios_cronet_buildflags") {
   flags = [ "CRONET_BUILD=$is_cronet_build" ]
 }
 
+enable_message_pump_epoll = is_linux || is_chromeos || is_android
+buildflag_header("message_pump_buildflags") {
+  header = "message_pump_buildflags.h"
+  header_dir = "base/message_loop"
+  flags = [ "ENABLE_MESSAGE_PUMP_EPOLL=$enable_message_pump_epoll" ]
+}
+
 # Base and everything it depends on should be a static library rather than
 # a source set. Base is more of a "library" in the classic sense in that many
 # small parts of it are used in many different contexts. This combined with a
@@ -180,6 +187,10 @@ mixed_component("base") {
     "allocator/allocator_check.h",
     "allocator/allocator_extension.cc",
     "allocator/allocator_extension.h",
+    "allocator/dispatcher/dispatcher.cc",
+    "allocator/dispatcher/dispatcher.h",
+    "allocator/dispatcher/reentry_guard.cc",
+    "allocator/dispatcher/reentry_guard.h",
     "as_const.h",
     "at_exit.cc",
     "at_exit.h",
@@ -217,6 +228,8 @@ mixed_component("base") {
     "cancelable_callback.h",
     "check.cc",
     "check.h",
+    "check_is_test.cc",
+    "check_is_test.h",
     "check_op.cc",
     "check_op.h",
     "command_line.cc",
@@ -400,6 +413,7 @@ mixed_component("base") {
     "memory/raw_ptr_asan_service.cc",
     "memory/raw_ptr_asan_service.h",
     "memory/raw_ptr_exclusion.h",
+    "memory/raw_ref.h",
     "memory/raw_scoped_refptr_mismatch_checker.h",
     "memory/read_only_shared_memory_region.cc",
     "memory/read_only_shared_memory_region.h",
@@ -498,7 +512,6 @@ mixed_component("base") {
     "native_library.cc",
     "native_library.h",
     "no_destructor.h",
-    "notreached.cc",
     "notreached.h",
     "observer_list.h",
     "observer_list_internal.cc",
@@ -552,7 +565,6 @@ mixed_component("base") {
     "profiler/metadata_recorder.h",
     "profiler/module_cache.cc",
     "profiler/module_cache.h",
-    "profiler/native_unwinder.h",
     "profiler/profile_builder.h",
     "profiler/register_context.h",
     "profiler/sample_metadata.cc",
@@ -914,6 +926,7 @@ mixed_component("base") {
     "trace_event/trace_id_helper.h",
     "traits_bag.h",
     "tuple.h",
+    "types/always_false.h",
     "types/expected.h",
     "types/expected_internal.h",
     "types/id_type.h",
@@ -1266,9 +1279,9 @@ mixed_component("base") {
       "process/process_iterator_mac.cc",
       "process/process_mac.cc",
       "process/process_metrics_mac.cc",
+      "profiler/frame_pointer_unwinder.cc",
+      "profiler/frame_pointer_unwinder.h",
       "profiler/module_cache_mac.cc",
-      "profiler/native_unwinder_apple.cc",
-      "profiler/native_unwinder_apple.h",
       "profiler/stack_sampler_mac.cc",
       "profiler/suspendable_thread_delegate_mac.cc",
       "profiler/suspendable_thread_delegate_mac.h",
@@ -1314,8 +1327,8 @@ mixed_component("base") {
 
     if (ios_stack_profiler_enabled) {
       sources += [
-        "profiler/native_unwinder_apple.cc",
+        "profiler/frame_pointer_unwinder.cc",
-        "profiler/native_unwinder_apple.h",
+        "profiler/frame_pointer_unwinder.h",
         "profiler/suspendable_thread_delegate_mac.cc",
         "profiler/suspendable_thread_delegate_mac.h",
       ]
@@ -1415,15 +1428,13 @@ mixed_component("base") {
 
   configs += [
     "//build/config:precompiled_headers",
-
+    "//build/config/compiler:prevent_unsafe_narrowing",
-    # TODO(crbug.com/1292951): Enable.
-    # "//build/config/compiler:prevent_unsafe_narrowing",
-
     "//build/config/compiler:wexit_time_destructors",
     "//build/config/compiler:wglobal_constructors",
   ]
 
   deps = [
+    ":message_pump_buildflags",
     "//base/allocator:buildflags",
     "//base/third_party/double_conversion",
     "//base/third_party/dynamic_annotations",
@@ -1676,8 +1687,14 @@ mixed_component("base") {
       "logging_chromeos.cc",
       "system/sys_info_chromeos.cc",
     ]
-    if (is_chromeos_ash) {
+
     sources += [ "power_monitor/power_monitor_device_source_chromeos.cc" ]
+
+    if (current_cpu == "x64") {
+      sources += [
+        "profiler/frame_pointer_unwinder.cc",
+        "profiler/frame_pointer_unwinder.h",
+      ]
     }
   }
 
@@ -1792,6 +1809,7 @@ mixed_component("base") {
 
     deps += [
       "//third_party/fuchsia-sdk/sdk/fidl/fuchsia.buildinfo",
+      "//third_party/fuchsia-sdk/sdk/fidl/fuchsia.hwinfo",
       "//third_party/fuchsia-sdk/sdk/fidl/fuchsia.media",
       "//third_party/fuchsia-sdk/sdk/fidl/fuchsia.sys",
       "//third_party/fuchsia-sdk/sdk/pkg/async-default",
@@ -2178,7 +2196,7 @@ mixed_component("base") {
   }
 
   if (dep_libevent) {
-    deps += [ "//base/third_party/libevent" ]
+    deps += [ "//third_party/libevent" ]
   }
 
   if (use_libevent) {
@@ -2188,6 +2206,13 @@ mixed_component("base") {
     ]
   }
 
+  if (enable_message_pump_epoll) {
+    sources += [
+      "message_loop/message_pump_epoll.cc",
+      "message_loop/message_pump_epoll.h",
+    ]
+  }
+
   # Android and MacOS have their own custom shared memory handle
   # implementations. e.g. due to supporting both POSIX and native handles.
   if (is_posix && !is_android && !is_apple) {
@@ -2229,8 +2254,7 @@ mixed_component("base") {
     ]
   }
 
-  if ((is_posix && !is_apple && !is_android && !is_chromeos_ash) ||
+  if ((is_posix && !is_apple && !is_android && !is_chromeos) || is_fuchsia) {
-      is_fuchsia) {
     sources += [ "power_monitor/power_monitor_device_source_stub.cc" ]
   }
 
@@ -2287,8 +2311,6 @@ mixed_component("base") {
       "trace_event/process_memory_dump.cc",
       "trace_event/process_memory_dump.h",
       "trace_event/task_execution_macros.h",
-      "trace_event/thread_instruction_count.cc",
-      "trace_event/thread_instruction_count.h",
       "trace_event/trace_arguments.cc",
       "trace_event/trace_arguments.h",
       "trace_event/trace_buffer.cc",

src/base/DEPS

@@ -3,6 +3,7 @@ include_rules = [
   "+third_party/apple_apsl",
   "+third_party/boringssl/src/include",
   "+third_party/ced",
+  "+third_party/libevent",
   "+third_party/libunwindstack/src/libunwindstack/include",
   "+third_party/lss",
   "+third_party/modp_b64",

src/base/allocator/OWNERS

@@ -2,7 +2,7 @@ lizeb@chromium.org
 primiano@chromium.org
 wfh@chromium.org
 
-per-file allocator.gni=bartekn@chromium.org
+per-file allocator.gni=file://base/allocator/partition_allocator/OWNERS
-per-file allocator_shim_default_dispatch_to_partition_alloc*=bartekn@chromium.org
+per-file allocator_shim_default_dispatch_to_partition_alloc*=file://base/allocator/partition_allocator/OWNERS
-per-file partition_alloc*=bartekn@chromium.org
+per-file partition_alloc*=file://base/allocator/partition_allocator/OWNERS
-per-file BUILD.gn=bartekn@chromium.org
+per-file BUILD.gn=file://base/allocator/partition_allocator/OWNERS

src/base/allocator/allocator.gni

@@ -81,7 +81,8 @@ if (is_win && use_allocator_shim) {
          "The allocator shim doesn't work for the component build on Windows.")
 }
 
-_is_brp_supported = (is_win || is_android) && use_allocator == "partition"
+_is_brp_supported = (is_win || is_android || is_linux || is_mac ||
+                     is_chromeos) && use_allocator == "partition"
 
 declare_args() {
   # Set use_backup_ref_ptr true to use BackupRefPtr (BRP) as the implementation
@@ -112,7 +113,10 @@ declare_args() {
   # Finch.
   use_fake_binary_experiment = false
 
-  use_asan_backup_ref_ptr = false
+  # The supported platforms are supposed to match `_is_brp_supported`, but we
+  # enable the feature on Linux early because it's most widely used for security
+  # research
+  use_asan_backup_ref_ptr = is_asan && (is_win || is_android || is_linux)
 }
 
 # Prevent using BackupRefPtr when PartitionAlloc-Everywhere isn't used.

src/base/allocator/allocator_interception_mac.mm

@@ -44,8 +44,7 @@
 #include "base/mac/mac_util.h"
 #endif
 
-namespace base {
+namespace base::allocator {
-namespace allocator {
 
 bool g_replaced_default_zone = false;
 
@@ -237,9 +236,9 @@ void* oom_killer_memalign_purgeable(struct _malloc_zone_t* zone,
 
 bool CanGetContextForCFAllocator() {
 #if BUILDFLAG(IS_IOS)
-  return !base::ios::IsRunningOnOrLater(16, 0, 0);
+  return !base::ios::IsRunningOnOrLater(17, 0, 0);
 #else
-  return !base::mac::IsOSLaterThan12_DontCallThis();
+  return !base::mac::IsOSLaterThan13_DontCallThis();
 #endif
 }
 
@@ -258,7 +257,7 @@ void* oom_killer_cfallocator_system_default(CFIndex alloc_size,
                                             void* info) {
   void* result = g_old_cfallocator_system_default(alloc_size, hint, info);
   if (!result)
-    TerminateBecauseOutOfMemory(alloc_size);
+    TerminateBecauseOutOfMemory(static_cast<size_t>(alloc_size));
   return result;
 }
 
@@ -267,7 +266,7 @@ void* oom_killer_cfallocator_malloc(CFIndex alloc_size,
                                     void* info) {
   void* result = g_old_cfallocator_malloc(alloc_size, hint, info);
   if (!result)
-    TerminateBecauseOutOfMemory(alloc_size);
+    TerminateBecauseOutOfMemory(static_cast<size_t>(alloc_size));
   return result;
 }
 
@@ -276,7 +275,7 @@ void* oom_killer_cfallocator_malloc_zone(CFIndex alloc_size,
                                          void* info) {
   void* result = g_old_cfallocator_malloc_zone(alloc_size, hint, info);
   if (!result)
-    TerminateBecauseOutOfMemory(alloc_size);
+    TerminateBecauseOutOfMemory(static_cast<size_t>(alloc_size));
   return result;
 }
 
@@ -609,5 +608,4 @@ void ReplaceZoneFunctions(ChromeMallocZone* zone,
   }
 }
 
-}  // namespace allocator
+}  // namespace base::allocator
-}  // namespace base

src/base/allocator/allocator_shim.h

@@ -174,6 +174,7 @@ BASE_EXPORT void InitializeAllocatorShim();
 BASE_EXPORT void EnablePartitionAllocMemoryReclaimer();
 
 using EnableBrp = base::StrongAlias<class EnableBrpTag, bool>;
+using EnableBrpZapping = base::StrongAlias<class EnableBrpZappingTag, bool>;
 using SplitMainPartition = base::StrongAlias<class SplitMainPartitionTag, bool>;
 using UseDedicatedAlignedPartition =
     base::StrongAlias<class UseDedicatedAlignedPartitionTag, bool>;
@@ -185,12 +186,13 @@ using AlternateBucketDistribution =
 // thread-cache on the main (malloc) partition will be disabled.
 BASE_EXPORT void ConfigurePartitions(
     EnableBrp enable_brp,
+    EnableBrpZapping enable_brp_zapping,
     SplitMainPartition split_main_partition,
     UseDedicatedAlignedPartition use_dedicated_aligned_partition,
     AlternateBucketDistribution use_alternate_bucket_distribution);
 
 #if defined(PA_ALLOW_PCSCAN)
-BASE_EXPORT void EnablePCScan(base::internal::PCScan::InitConfig);
+BASE_EXPORT void EnablePCScan(partition_alloc::internal::PCScan::InitConfig);
 #endif
 #endif  // BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
 

src/base/allocator/allocator_shim_default_dispatch_to_partition_alloc.cc

@@ -27,6 +27,7 @@
 #include "base/feature_list.h"
 #include "base/memory/nonscannable_memory.h"
 #include "base/numerics/checked_math.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
 #include "build/chromecast_buildflags.h"
@@ -146,26 +147,27 @@ T* LeakySingleton<T, Constructor>::GetSlowPath() {
 class MainPartitionConstructor {
  public:
   static partition_alloc::ThreadSafePartitionRoot* New(void* buffer) {
-    constexpr base::PartitionOptions::ThreadCache thread_cache =
+    constexpr partition_alloc::PartitionOptions::ThreadCache thread_cache =
 #if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
         // Additional partitions may be created in ConfigurePartitions(). Since
         // only one partition can have thread cache enabled, postpone the
         // decision to turn the thread cache on until after that call.
         // TODO(bartekn): Enable it here by default, once the "split-only" mode
         // is no longer needed.
-        base::PartitionOptions::ThreadCache::kDisabled;
+        partition_alloc::PartitionOptions::ThreadCache::kDisabled;
 #else   // BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
         // Other tests, such as the ThreadCache tests create a thread cache,
         // and only one is supported at a time.
-        base::PartitionOptions::ThreadCache::kDisabled;
+        partition_alloc::PartitionOptions::ThreadCache::kDisabled;
 #endif  // BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
     auto* new_root = new (buffer) partition_alloc::ThreadSafePartitionRoot({
-        base::PartitionOptions::AlignedAlloc::kAllowed,
+        partition_alloc::PartitionOptions::AlignedAlloc::kAllowed,
         thread_cache,
-        base::PartitionOptions::Quarantine::kAllowed,
+        partition_alloc::PartitionOptions::Quarantine::kAllowed,
-        base::PartitionOptions::Cookie::kAllowed,
+        partition_alloc::PartitionOptions::Cookie::kAllowed,
-        base::PartitionOptions::BackupRefPtr::kDisabled,
+        partition_alloc::PartitionOptions::BackupRefPtr::kDisabled,
-        base::PartitionOptions::UseConfigurablePool::kNo,
+        partition_alloc::PartitionOptions::BackupRefPtrZapping::kDisabled,
+        partition_alloc::PartitionOptions::UseConfigurablePool::kNo,
     });
 
     return new_root;
@@ -275,9 +277,9 @@ namespace internal {
 
 namespace {
 #if BUILDFLAG(IS_APPLE)
-int g_alloc_flags = 0;
+unsigned int g_alloc_flags = 0;
 #else
-constexpr int g_alloc_flags = 0;
+constexpr unsigned int g_alloc_flags = 0;
 #endif
 }  // namespace
 
@@ -300,7 +302,7 @@ void PartitionAllocSetCallNewHandlerOnMallocFailure(bool value) {
 void* PartitionMalloc(const AllocatorDispatch*, size_t size, void* context) {
   ScopedDisallowAllocations guard{};
   return Allocator()->AllocWithFlagsNoHooks(
-      0 | g_alloc_flags, MaybeAdjustSize(size),
+      g_alloc_flags, MaybeAdjustSize(size),
       partition_alloc::PartitionPageSize());
 }
 
@@ -513,17 +515,19 @@ void PartitionBatchFree(const AllocatorDispatch*,
 }
 
 // static
-ThreadSafePartitionRoot* PartitionAllocMalloc::Allocator() {
+partition_alloc::ThreadSafePartitionRoot* PartitionAllocMalloc::Allocator() {
   return ::Allocator();
 }
 
 // static
-ThreadSafePartitionRoot* PartitionAllocMalloc::OriginalAllocator() {
+partition_alloc::ThreadSafePartitionRoot*
+PartitionAllocMalloc::OriginalAllocator() {
   return ::OriginalAllocator();
 }
 
 // static
-ThreadSafePartitionRoot* PartitionAllocMalloc::AlignedAllocator() {
+partition_alloc::ThreadSafePartitionRoot*
+PartitionAllocMalloc::AlignedAllocator() {
   return ::AlignedAllocator();
 }
 
@@ -563,6 +567,7 @@ alignas(partition_alloc::ThreadSafePartitionRoot) uint8_t
 
 void ConfigurePartitions(
     EnableBrp enable_brp,
+    EnableBrpZapping enable_brp_zapping,
     SplitMainPartition split_main_partition,
     UseDedicatedAlignedPartition use_dedicated_aligned_partition,
     AlternateBucketDistribution use_alternate_bucket_distribution) {
@@ -596,18 +601,22 @@ void ConfigurePartitions(
     PA_DCHECK(!current_root->flags.with_thread_cache);
     return;
   }
-
+  auto* new_root = new (g_allocator_buffer_for_new_main_partition)
-  auto* new_root =
+      partition_alloc::ThreadSafePartitionRoot({
-      new (g_allocator_buffer_for_new_main_partition) ThreadSafePartitionRoot({
           !use_dedicated_aligned_partition
-              ? base::PartitionOptions::AlignedAlloc::kAllowed
+              ? partition_alloc::PartitionOptions::AlignedAlloc::kAllowed
-              : base::PartitionOptions::AlignedAlloc::kDisallowed,
+              : partition_alloc::PartitionOptions::AlignedAlloc::kDisallowed,
-          base::PartitionOptions::ThreadCache::kDisabled,
+          partition_alloc::PartitionOptions::ThreadCache::kDisabled,
-          base::PartitionOptions::Quarantine::kAllowed,
+          partition_alloc::PartitionOptions::Quarantine::kAllowed,
-          base::PartitionOptions::Cookie::kAllowed,
+          partition_alloc::PartitionOptions::Cookie::kAllowed,
-          enable_brp ? base::PartitionOptions::BackupRefPtr::kEnabled
+          enable_brp
-                     : base::PartitionOptions::BackupRefPtr::kDisabled,
+              ? partition_alloc::PartitionOptions::BackupRefPtr::kEnabled
-          base::PartitionOptions::UseConfigurablePool::kNo,
+              : partition_alloc::PartitionOptions::BackupRefPtr::kDisabled,
+          enable_brp_zapping
+              ? partition_alloc::PartitionOptions::BackupRefPtrZapping::kEnabled
+              : partition_alloc::PartitionOptions::BackupRefPtrZapping::
+                    kDisabled,
+          partition_alloc::PartitionOptions::UseConfigurablePool::kNo,
       });
 
   partition_alloc::ThreadSafePartitionRoot* new_aligned_root;
@@ -615,13 +624,14 @@ void ConfigurePartitions(
     // TODO(bartekn): Use the original root instead of creating a new one. It'd
     // result in one less partition, but come at a cost of commingling types.
     new_aligned_root = new (g_allocator_buffer_for_aligned_alloc_partition)
-        ThreadSafePartitionRoot({
+        partition_alloc::ThreadSafePartitionRoot({
-            base::PartitionOptions::AlignedAlloc::kAllowed,
+            partition_alloc::PartitionOptions::AlignedAlloc::kAllowed,
-            base::PartitionOptions::ThreadCache::kDisabled,
+            partition_alloc::PartitionOptions::ThreadCache::kDisabled,
-            base::PartitionOptions::Quarantine::kAllowed,
+            partition_alloc::PartitionOptions::Quarantine::kAllowed,
-            base::PartitionOptions::Cookie::kAllowed,
+            partition_alloc::PartitionOptions::Cookie::kAllowed,
-            base::PartitionOptions::BackupRefPtr::kDisabled,
+            partition_alloc::PartitionOptions::BackupRefPtr::kDisabled,
-            base::PartitionOptions::UseConfigurablePool::kNo,
+            partition_alloc::PartitionOptions::BackupRefPtrZapping::kDisabled,
+            partition_alloc::PartitionOptions::UseConfigurablePool::kNo,
         });
   } else {
     // The new main root can also support AlignedAlloc.
@@ -643,8 +653,9 @@ void ConfigurePartitions(
   PA_CHECK(current_aligned_root == g_original_root);
 
   // Purge memory, now that the traffic to the original partition is cut off.
-  current_root->PurgeMemory(PurgeFlags::kDecommitEmptySlotSpans |
+  current_root->PurgeMemory(
-                            PurgeFlags::kDiscardUnusedSystemPages);
+      partition_alloc::PurgeFlags::kDecommitEmptySlotSpans |
+      partition_alloc::PurgeFlags::kDiscardUnusedSystemPages);
 
   if (!use_alternate_bucket_distribution) {
     g_root.Get()->SwitchToDenserBucketDistribution();
@@ -653,16 +664,18 @@ void ConfigurePartitions(
 }
 
 #if defined(PA_ALLOW_PCSCAN)
-void EnablePCScan(base::internal::PCScan::InitConfig config) {
+void EnablePCScan(partition_alloc::internal::PCScan::InitConfig config) {
   partition_alloc::internal::base::PlatformThread::SetThreadNameHook(
       &::base::PlatformThread::SetName);
-  internal::PCScan::Initialize(config);
+  partition_alloc::internal::PCScan::Initialize(config);
 
-  internal::PCScan::RegisterScannableRoot(Allocator());
+  partition_alloc::internal::PCScan::RegisterScannableRoot(Allocator());
   if (OriginalAllocator() != nullptr)
-    internal::PCScan::RegisterScannableRoot(OriginalAllocator());
+    partition_alloc::internal::PCScan::RegisterScannableRoot(
+        OriginalAllocator());
   if (Allocator() != AlignedAllocator())
-    internal::PCScan::RegisterScannableRoot(AlignedAllocator());
+    partition_alloc::internal::PCScan::RegisterScannableRoot(
+        AlignedAllocator());
 
   internal::NonScannableAllocator::Instance().NotifyPCScanEnabled();
   internal::NonQuarantinableAllocator::Instance().NotifyPCScanEnabled();
@@ -724,11 +737,11 @@ SHIM_ALWAYS_EXPORT int mallopt(int cmd, int value) __THROW {
 
 #if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
 SHIM_ALWAYS_EXPORT struct mallinfo mallinfo(void) __THROW {
-  base::SimplePartitionStatsDumper allocator_dumper;
+  partition_alloc::SimplePartitionStatsDumper allocator_dumper;
   Allocator()->DumpStats("malloc", true, &allocator_dumper);
   // TODO(bartekn): Dump OriginalAllocator() into "malloc" as well.
 
-  base::SimplePartitionStatsDumper aligned_allocator_dumper;
+  partition_alloc::SimplePartitionStatsDumper aligned_allocator_dumper;
   if (AlignedAllocator() != Allocator()) {
     AlignedAllocator()->DumpStats("posix_memalign", true,
                                   &aligned_allocator_dumper);
@@ -737,13 +750,13 @@ SHIM_ALWAYS_EXPORT struct mallinfo mallinfo(void) __THROW {
   // Dump stats for nonscannable and nonquarantinable allocators.
   auto& nonscannable_allocator =
       base::internal::NonScannableAllocator::Instance();
-  base::SimplePartitionStatsDumper nonscannable_allocator_dumper;
+  partition_alloc::SimplePartitionStatsDumper nonscannable_allocator_dumper;
   if (auto* nonscannable_root = nonscannable_allocator.root())
     nonscannable_root->DumpStats("malloc", true,
                                  &nonscannable_allocator_dumper);
   auto& nonquarantinable_allocator =
       base::internal::NonQuarantinableAllocator::Instance();
-  base::SimplePartitionStatsDumper nonquarantinable_allocator_dumper;
+  partition_alloc::SimplePartitionStatsDumper nonquarantinable_allocator_dumper;
   if (auto* nonquarantinable_root = nonquarantinable_allocator.root())
     nonquarantinable_root->DumpStats("malloc", true,
                                      &nonquarantinable_allocator_dumper);
@@ -752,20 +765,23 @@ SHIM_ALWAYS_EXPORT struct mallinfo mallinfo(void) __THROW {
   info.arena = 0;  // Memory *not* allocated with mmap().
 
   // Memory allocated with mmap(), aka virtual size.
-  info.hblks = allocator_dumper.stats().total_mmapped_bytes +
+  info.hblks = base::checked_cast<decltype(info.hblks)>(
+      allocator_dumper.stats().total_mmapped_bytes +
       aligned_allocator_dumper.stats().total_mmapped_bytes +
       nonscannable_allocator_dumper.stats().total_mmapped_bytes +
-               nonquarantinable_allocator_dumper.stats().total_mmapped_bytes;
+      nonquarantinable_allocator_dumper.stats().total_mmapped_bytes);
   // Resident bytes.
-  info.hblkhd = allocator_dumper.stats().total_resident_bytes +
+  info.hblkhd = base::checked_cast<decltype(info.hblkhd)>(
+      allocator_dumper.stats().total_resident_bytes +
       aligned_allocator_dumper.stats().total_resident_bytes +
       nonscannable_allocator_dumper.stats().total_resident_bytes +
-                nonquarantinable_allocator_dumper.stats().total_resident_bytes;
+      nonquarantinable_allocator_dumper.stats().total_resident_bytes);
   // Allocated bytes.
-  info.uordblks = allocator_dumper.stats().total_active_bytes +
+  info.uordblks = base::checked_cast<decltype(info.uordblks)>(
+      allocator_dumper.stats().total_active_bytes +
       aligned_allocator_dumper.stats().total_active_bytes +
       nonscannable_allocator_dumper.stats().total_active_bytes +
-                  nonquarantinable_allocator_dumper.stats().total_active_bytes;
+      nonquarantinable_allocator_dumper.stats().total_active_bytes);
 
   return info;
 }

src/base/allocator/allocator_shim_default_dispatch_to_partition_alloc.h

@@ -16,11 +16,11 @@ void PartitionAllocSetCallNewHandlerOnMallocFailure(bool value);
 
 class BASE_EXPORT PartitionAllocMalloc {
  public:
-  static ThreadSafePartitionRoot* Allocator();
+  static partition_alloc::ThreadSafePartitionRoot* Allocator();
   // May return |nullptr|, will never return the same pointer as |Allocator()|.
-  static ThreadSafePartitionRoot* OriginalAllocator();
+  static partition_alloc::ThreadSafePartitionRoot* OriginalAllocator();
   // May return the same pointer as |Allocator()|.
-  static ThreadSafePartitionRoot* AlignedAllocator();
+  static partition_alloc::ThreadSafePartitionRoot* AlignedAllocator();
 };
 
 BASE_EXPORT void* PartitionMalloc(const base::allocator::AllocatorDispatch*,

src/base/allocator/allocator_shim_override_cpp_symbols.h

@@ -17,43 +17,6 @@
 #include "base/compiler_specific.h"
 #include "build/build_config.h"
 
-// std::align_val_t isn't available until C++17, but we want to override aligned
-// new/delete anyway to prevent a possible situation where a library gets loaded
-// in that uses the aligned operators.  We want to avoid a situation where
-// separate heaps are used.
-// TODO(thomasanderson): Remove this once building with C++17 or later.
-#if defined(__cpp_aligned_new) && __cpp_aligned_new >= 201606
-#define ALIGN_VAL_T std::align_val_t
-#define ALIGN_LINKAGE
-#define ALIGN_NEW operator new
-#define ALIGN_NEW_NOTHROW operator new
-#define ALIGN_DEL operator delete
-#define ALIGN_DEL_SIZED operator delete
-#define ALIGN_DEL_NOTHROW operator delete
-#define ALIGN_NEW_ARR operator new[]
-#define ALIGN_NEW_ARR_NOTHROW operator new[]
-#define ALIGN_DEL_ARR operator delete[]
-#define ALIGN_DEL_ARR_SIZED operator delete[]
-#define ALIGN_DEL_ARR_NOTHROW operator delete[]
-#else
-#define ALIGN_VAL_T size_t
-#define ALIGN_LINKAGE extern "C"
-#if BUILDFLAG(IS_WIN)
-#error "Mangling is different on these platforms."
-#else
-#define ALIGN_NEW _ZnwmSt11align_val_t
-#define ALIGN_NEW_NOTHROW _ZnwmSt11align_val_tRKSt9nothrow_t
-#define ALIGN_DEL _ZdlPvSt11align_val_t
-#define ALIGN_DEL_SIZED _ZdlPvmSt11align_val_t
-#define ALIGN_DEL_NOTHROW _ZdlPvSt11align_val_tRKSt9nothrow_t
-#define ALIGN_NEW_ARR _ZnamSt11align_val_t
-#define ALIGN_NEW_ARR_NOTHROW _ZnamSt11align_val_tRKSt9nothrow_t
-#define ALIGN_DEL_ARR _ZdaPvSt11align_val_t
-#define ALIGN_DEL_ARR_SIZED _ZdaPvmSt11align_val_t
-#define ALIGN_DEL_ARR_NOTHROW _ZdaPvSt11align_val_tRKSt9nothrow_t
-#endif
-#endif
-
 #if !BUILDFLAG(IS_APPLE)
 #define SHIM_CPP_SYMBOLS_EXPORT SHIM_ALWAYS_EXPORT
 #else
@@ -110,57 +73,58 @@ SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p, size_t) __THROW {
   ShimCppDelete(p);
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void* ALIGN_NEW(std::size_t size,
+SHIM_CPP_SYMBOLS_EXPORT void* operator new(std::size_t size,
-                                                      ALIGN_VAL_T alignment) {
+                                           std::align_val_t alignment) {
   return ShimCppAlignedNew(size, static_cast<size_t>(alignment));
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void* ALIGN_NEW_NOTHROW(
+SHIM_CPP_SYMBOLS_EXPORT void* operator new(std::size_t size,
-    std::size_t size,
+                                           std::align_val_t alignment,
-    ALIGN_VAL_T alignment,
                                            const std::nothrow_t&) __THROW {
   return ShimCppAlignedNew(size, static_cast<size_t>(alignment));
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void ALIGN_DEL(void* p,
+SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p,
-                                                     ALIGN_VAL_T) __THROW {
+                                             std::align_val_t) __THROW {
   ShimCppDelete(p);
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void
+SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p,
-ALIGN_DEL_SIZED(void* p, std::size_t size, ALIGN_VAL_T) __THROW {
-  ShimCppDelete(p);
-}
-
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void
-ALIGN_DEL_NOTHROW(void* p, ALIGN_VAL_T, const std::nothrow_t&) __THROW {
-  ShimCppDelete(p);
-}
-
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void* ALIGN_NEW_ARR(
                                              std::size_t size,
-    ALIGN_VAL_T alignment) {
+                                             std::align_val_t) __THROW {
+  ShimCppDelete(p);
+}
+
+SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p,
+                                             std::align_val_t,
+                                             const std::nothrow_t&) __THROW {
+  ShimCppDelete(p);
+}
+
+SHIM_CPP_SYMBOLS_EXPORT void* operator new[](std::size_t size,
+                                             std::align_val_t alignment) {
   return ShimCppAlignedNew(size, static_cast<size_t>(alignment));
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void* ALIGN_NEW_ARR_NOTHROW(
+SHIM_CPP_SYMBOLS_EXPORT void* operator new[](std::size_t size,
-    std::size_t size,
+                                             std::align_val_t alignment,
-    ALIGN_VAL_T alignment,
                                              const std::nothrow_t&) __THROW {
   return ShimCppAlignedNew(size, static_cast<size_t>(alignment));
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void ALIGN_DEL_ARR(void* p,
+SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
-                                                         ALIGN_VAL_T) __THROW {
+                                               std::align_val_t) __THROW {
   ShimCppDelete(p);
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void
+SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
-ALIGN_DEL_ARR_SIZED(void* p, std::size_t size, ALIGN_VAL_T) __THROW {
+                                               std::size_t size,
+                                               std::align_val_t) __THROW {
   ShimCppDelete(p);
 }
 
-ALIGN_LINKAGE SHIM_CPP_SYMBOLS_EXPORT void
+SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
-ALIGN_DEL_ARR_NOTHROW(void* p, ALIGN_VAL_T, const std::nothrow_t&) __THROW {
+                                               std::align_val_t,
+                                               const std::nothrow_t&) __THROW {
   ShimCppDelete(p);
 }

src/base/allocator/allocator_shim_override_linker_wrapped_symbols.h

@@ -122,7 +122,10 @@ SHIM_ALWAYS_EXPORT int __wrap_vasprintf(char** strp,
       malloc(kInitialSize));  // Our malloc() doesn't return nullptr.
 
   int actual_size = vsnprintf(*strp, kInitialSize, fmt, va_args);
-  *strp = static_cast<char*>(realloc(*strp, actual_size + 1));
+  if (actual_size < 0)
+    return actual_size;
+  *strp =
+      static_cast<char*>(realloc(*strp, static_cast<size_t>(actual_size + 1)));
 
   // Now we know the size. This is not very efficient, but we cannot really do
   // better without accessing internal libc functions, or reimplementing
@@ -131,7 +134,7 @@ SHIM_ALWAYS_EXPORT int __wrap_vasprintf(char** strp,
   // This is very lightly used in Chromium in practice, see crbug.com/116558 for
   // details.
   if (actual_size >= kInitialSize)
-    return vsnprintf(*strp, actual_size + 1, fmt, va_args);
+    return vsnprintf(*strp, static_cast<size_t>(actual_size + 1), fmt, va_args);
 
   return actual_size;
 }

src/base/allocator/dispatcher/dispatcher.cc

@@ -0,0 +1,239 @@
+// Copyright (c) 2022 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/allocator/dispatcher/dispatcher.h"
+
+#include "base/allocator/allocator_shim.h"
+#include "base/allocator/buildflags.h"
+#include "base/allocator/dispatcher/reentry_guard.h"
+#include "base/allocator/partition_allocator/partition_alloc.h"
+#include "base/sampling_heap_profiler/poisson_allocation_sampler.h"
+
+#if BUILDFLAG(USE_ALLOCATOR_SHIM)
+namespace base::allocator::dispatcher::allocator_shim_details {
+namespace {
+
+using allocator::AllocatorDispatch;
+
+void* AllocFn(const AllocatorDispatch* self, size_t size, void* context) {
+  ReentryGuard guard;
+  void* address = self->next->alloc_function(self->next, size, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+void* AllocUncheckedFn(const AllocatorDispatch* self,
+                       size_t size,
+                       void* context) {
+  ReentryGuard guard;
+  void* address =
+      self->next->alloc_unchecked_function(self->next, size, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+void* AllocZeroInitializedFn(const AllocatorDispatch* self,
+                             size_t n,
+                             size_t size,
+                             void* context) {
+  ReentryGuard guard;
+  void* address =
+      self->next->alloc_zero_initialized_function(self->next, n, size, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, n * size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+void* AllocAlignedFn(const AllocatorDispatch* self,
+                     size_t alignment,
+                     size_t size,
+                     void* context) {
+  ReentryGuard guard;
+  void* address =
+      self->next->alloc_aligned_function(self->next, alignment, size, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+void* ReallocFn(const AllocatorDispatch* self,
+                void* address,
+                size_t size,
+                void* context) {
+  ReentryGuard guard;
+  // Note: size == 0 actually performs free.
+  PoissonAllocationSampler::RecordFree(address);
+  address = self->next->realloc_function(self->next, address, size, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+void FreeFn(const AllocatorDispatch* self, void* address, void* context) {
+  // Note: The RecordFree should be called before free_function
+  // (here and in other places).
+  // That is because we need to remove the recorded allocation sample before
+  // free_function, as once the latter is executed the address becomes available
+  // and can be allocated by another thread. That would be racy otherwise.
+  PoissonAllocationSampler::RecordFree(address);
+  self->next->free_function(self->next, address, context);
+}
+
+size_t GetSizeEstimateFn(const AllocatorDispatch* self,
+                         void* address,
+                         void* context) {
+  return self->next->get_size_estimate_function(self->next, address, context);
+}
+
+unsigned BatchMallocFn(const AllocatorDispatch* self,
+                       size_t size,
+                       void** results,
+                       unsigned num_requested,
+                       void* context) {
+  ReentryGuard guard;
+  unsigned num_allocated = self->next->batch_malloc_function(
+      self->next, size, results, num_requested, context);
+  if (LIKELY(guard)) {
+    for (unsigned i = 0; i < num_allocated; ++i) {
+      PoissonAllocationSampler::RecordAlloc(
+          results[i], size, PoissonAllocationSampler::kMalloc, nullptr);
+    }
+  }
+  return num_allocated;
+}
+
+void BatchFreeFn(const AllocatorDispatch* self,
+                 void** to_be_freed,
+                 unsigned num_to_be_freed,
+                 void* context) {
+  for (unsigned i = 0; i < num_to_be_freed; ++i)
+    PoissonAllocationSampler::RecordFree(to_be_freed[i]);
+  self->next->batch_free_function(self->next, to_be_freed, num_to_be_freed,
+                                  context);
+}
+
+void FreeDefiniteSizeFn(const AllocatorDispatch* self,
+                        void* address,
+                        size_t size,
+                        void* context) {
+  PoissonAllocationSampler::RecordFree(address);
+  self->next->free_definite_size_function(self->next, address, size, context);
+}
+
+static void* AlignedMallocFn(const AllocatorDispatch* self,
+                             size_t size,
+                             size_t alignment,
+                             void* context) {
+  ReentryGuard guard;
+  void* address =
+      self->next->aligned_malloc_function(self->next, size, alignment, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+static void* AlignedReallocFn(const AllocatorDispatch* self,
+                              void* address,
+                              size_t size,
+                              size_t alignment,
+                              void* context) {
+  ReentryGuard guard;
+  // Note: size == 0 actually performs free.
+  PoissonAllocationSampler::RecordFree(address);
+  address = self->next->aligned_realloc_function(self->next, address, size,
+                                                 alignment, context);
+  if (LIKELY(guard)) {
+    PoissonAllocationSampler::RecordAlloc(
+        address, size, PoissonAllocationSampler::kMalloc, nullptr);
+  }
+  return address;
+}
+
+static void AlignedFreeFn(const AllocatorDispatch* self,
+                          void* address,
+                          void* context) {
+  PoissonAllocationSampler::RecordFree(address);
+  self->next->aligned_free_function(self->next, address, context);
+}
+
+AllocatorDispatch g_allocator_dispatch = {&AllocFn,
+                                          &AllocUncheckedFn,
+                                          &AllocZeroInitializedFn,
+                                          &AllocAlignedFn,
+                                          &ReallocFn,
+                                          &FreeFn,
+                                          &GetSizeEstimateFn,
+                                          &BatchMallocFn,
+                                          &BatchFreeFn,
+                                          &FreeDefiniteSizeFn,
+                                          &AlignedMallocFn,
+                                          &AlignedReallocFn,
+                                          &AlignedFreeFn,
+                                          nullptr};
+
+}  // namespace
+}  // namespace base::allocator::dispatcher::allocator_shim_details
+#endif  // BUILDFLAG(USE_ALLOCATOR_SHIM)
+
+#if BUILDFLAG(USE_PARTITION_ALLOC) && !BUILDFLAG(IS_NACL)
+namespace base::allocator::dispatcher::partition_allocator_details {
+namespace {
+
+void PartitionAllocHook(void* address, size_t size, const char* type) {
+  PoissonAllocationSampler::RecordAlloc(
+      address, size, PoissonAllocationSampler::kPartitionAlloc, type);
+}
+
+void PartitionFreeHook(void* address) {
+  PoissonAllocationSampler::RecordFree(address);
+}
+
+}  // namespace
+}  // namespace base::allocator::dispatcher::partition_allocator_details
+#endif  // BUILDFLAG(USE_PARTITION_ALLOC) && !BUILDFLAG(IS_NACL)
+
+namespace base::allocator::dispatcher {
+
+void InstallStandardAllocatorHooks() {
+#if BUILDFLAG(USE_ALLOCATOR_SHIM)
+  allocator::InsertAllocatorDispatch(
+      &allocator_shim_details::g_allocator_dispatch);
+#else
+  // If the allocator shim isn't available, then we don't install any hooks.
+  // There's no point in printing an error message, since this can regularly
+  // happen for tests.
+#endif  // BUILDFLAG(USE_ALLOCATOR_SHIM)
+
+#if BUILDFLAG(USE_PARTITION_ALLOC) && !BUILDFLAG(IS_NACL)
+  partition_alloc::PartitionAllocHooks::SetObserverHooks(
+      &partition_allocator_details::PartitionAllocHook,
+      &partition_allocator_details::PartitionFreeHook);
+#endif  // BUILDFLAG(USE_PARTITION_ALLOC) && !BUILDFLAG(IS_NACL)
+}
+
+void RemoveStandardAllocatorHooksForTesting() {
+#if BUILDFLAG(USE_ALLOCATOR_SHIM)
+  allocator::RemoveAllocatorDispatchForTesting(
+      &allocator_shim_details::g_allocator_dispatch);  // IN-TEST
+#endif
+#if BUILDFLAG(USE_PARTITION_ALLOC) && !BUILDFLAG(IS_NACL)
+  partition_alloc::PartitionAllocHooks::SetObserverHooks(nullptr, nullptr);
+#endif
+}
+
+}  // namespace base::allocator::dispatcher

src/base/allocator/dispatcher/dispatcher.h

@@ -0,0 +1,17 @@
+// Copyright (c) 2022 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_ALLOCATOR_DISPATCHER_DISPATCHER_H_
+#define BASE_ALLOCATOR_DISPATCHER_DISPATCHER_H_
+
+#include "base/base_export.h"
+
+namespace base::allocator::dispatcher {
+
+void BASE_EXPORT InstallStandardAllocatorHooks();
+void BASE_EXPORT RemoveStandardAllocatorHooksForTesting();
+
+}  // namespace base::allocator::dispatcher
+
+#endif  // BASE_ALLOCATOR_DISPATCHER_DISPATCHER_H_

src/base/allocator/dispatcher/reentry_guard.cc

@@ -0,0 +1,20 @@
+// Copyright (c) 2022 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/allocator/dispatcher/reentry_guard.h"
+
+#include "base/check.h"
+#include "base/compiler_specific.h"
+#include "build/build_config.h"
+
+#if BUILDFLAG(IS_APPLE) || BUILDFLAG(IS_ANDROID)
+
+#include <pthread.h>
+
+namespace base::allocator::dispatcher {
+
+pthread_key_t ReentryGuard::entered_key_ = 0;
+
+}  // namespace base::allocator::dispatcher
+#endif

src/base/allocator/dispatcher/reentry_guard.h

@@ -0,0 +1,68 @@
+// Copyright (c) 2022 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_ALLOCATOR_DISPATCHER_REENTRY_GUARD_H_
+#define BASE_ALLOCATOR_DISPATCHER_REENTRY_GUARD_H_
+
+#include "base/base_export.h"
+#include "base/check.h"
+#include "base/compiler_specific.h"
+#include "build/build_config.h"
+
+#if BUILDFLAG(IS_APPLE) || BUILDFLAG(IS_ANDROID)
+#include <pthread.h>
+#endif
+
+namespace base::allocator::dispatcher {
+
+#if BUILDFLAG(IS_APPLE) || BUILDFLAG(IS_ANDROID)
+
+// The macOS implementation of libmalloc sometimes calls malloc recursively,
+// delegating allocations between zones. That causes our hooks being called
+// twice. The scoped guard allows us to detect that.
+//
+// Besides that the implementations of thread_local on macOS and Android
+// seem to allocate memory lazily on the first access to thread_local variables.
+// Make use of pthread TLS instead of C++ thread_local there.
+struct ReentryGuard {
+  ReentryGuard() : allowed_(!pthread_getspecific(entered_key_)) {
+    pthread_setspecific(entered_key_, reinterpret_cast<void*>(true));
+  }
+
+  ~ReentryGuard() {
+    if (LIKELY(allowed_))
+      pthread_setspecific(entered_key_, nullptr);
+  }
+
+  explicit operator bool() const noexcept { return allowed_; }
+
+  // This function must be called in very early of the process start-up in
+  // order to acquire a low TLS slot number because glibc TLS implementation
+  // will require a malloc call to allocate storage for a higher slot number
+  // (>= PTHREAD_KEY_2NDLEVEL_SIZE == 32).  c.f. heap_profiling::InitTLSSlot.
+  static void Init() {
+    int error = pthread_key_create(&entered_key_, nullptr);
+    CHECK(!error);
+  }
+
+ private:
+  static pthread_key_t entered_key_;
+  const bool allowed_;
+};
+
+#else
+
+// Use [[maybe_unused]] as this lightweight stand-in for the more heavyweight
+// ReentryGuard above will otherwise trigger the "unused code" warnings.
+struct [[maybe_unused]] BASE_EXPORT ReentryGuard {
+  constexpr explicit operator bool() const noexcept { return true; }
+
+  static void Init() {}
+};
+
+#endif
+
+}  // namespace base::allocator::dispatcher
+
+#endif  // BASE_ALLOCATOR_DISPATCHER_REENTRY_GUARD_H_

src/base/allocator/partition_alloc_features.cc

@@ -11,11 +11,19 @@
 namespace base {
 namespace features {
 
-// When set, instead of crashing when encountering a dangling raw_ptr, the
+const BASE_EXPORT Feature kPartitionAllocDanglingPtr{
-// signatures of the two stacktraces are logged. This is meant to be used only
+    "PartitionAllocDanglingPtr", FEATURE_DISABLED_BY_DEFAULT};
-// by Chromium developers. See /docs/dangling_ptr.md
+constexpr FeatureParam<DanglingPtrMode>::Option kDanglingPtrModeOption[] = {
-const BASE_EXPORT Feature kPartitionAllocDanglingPtrRecord{
+    {DanglingPtrMode::kCrash, "crash"},
-    "PartitionAllocDanglingPtrRecord", FEATURE_DISABLED_BY_DEFAULT};
+    {DanglingPtrMode::kLogSignature, "log_signature"},
+};
+const base::FeatureParam<DanglingPtrMode> kDanglingPtrModeParam{
+    &kPartitionAllocDanglingPtr,
+    "mode",
+    DanglingPtrMode::kCrash,
+    &kDanglingPtrModeOption,
+};
+
 #if defined(PA_ALLOW_PCSCAN)
 // If enabled, PCScan is turned on by default for all partitions that don't
 // disable it explicitly.
@@ -55,7 +63,8 @@ const BASE_EXPORT Feature kPartitionAllocLargeEmptySlotSpanRing{
 
 const Feature kPartitionAllocBackupRefPtr {
   "PartitionAllocBackupRefPtr",
-#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_WIN)
+#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_WIN) || \
+    (BUILDFLAG(USE_ASAN_BACKUP_REF_PTR) && BUILDFLAG(IS_LINUX))
       FEATURE_ENABLED_BY_DEFAULT
 #else
       FEATURE_DISABLED_BY_DEFAULT
@@ -79,6 +88,7 @@ const base::FeatureParam<BackupRefPtrEnabledProcesses>
 constexpr FeatureParam<BackupRefPtrMode>::Option kBackupRefPtrModeOptions[] = {
     {BackupRefPtrMode::kDisabled, "disabled"},
     {BackupRefPtrMode::kEnabled, "enabled"},
+    {BackupRefPtrMode::kEnabledWithoutZapping, "enabled-without-zapping"},
     {BackupRefPtrMode::kDisabledButSplitPartitions2Way,
      "disabled-but-2-way-split"},
     {BackupRefPtrMode::kDisabledButSplitPartitions3Way,

src/base/allocator/partition_alloc_features.h

@@ -17,7 +17,28 @@ struct Feature;
 
 namespace features {
 
-extern const BASE_EXPORT Feature kPartitionAllocDanglingPtrRecord;
+// See /docs/dangling_ptr.md
+//
+// Usage:
+// --enable-features=PartitionAllocDanglingPtr:mode/crash
+// --enable-features=PartitionAllocDanglingPtr:mode/log_signature
+extern const BASE_EXPORT Feature kPartitionAllocDanglingPtr;
+enum class DanglingPtrMode {
+  // Crash immediately after detecting a dangling raw_ptr.
+  kCrash,  // (default)
+
+  // Log the signature of every occurrences without crashing. It is used by
+  // bots.
+  // Format "[DanglingSignature]\t<1>\t<2>"
+  // 1. The function who freed the memory while it was still referenced.
+  // 2. The function who released the raw_ptr reference.
+  kLogSignature,
+
+  // Note: This will be extended with a single shot DumpWithoutCrashing.
+};
+extern const BASE_EXPORT base::FeatureParam<DanglingPtrMode>
+    kDanglingPtrModeParam;
+
 #if defined(PA_ALLOW_PCSCAN)
 extern const BASE_EXPORT Feature kPartitionAllocPCScan;
 #endif  // defined(PA_ALLOW_PCSCAN)
@@ -50,6 +71,9 @@ enum class BackupRefPtrMode {
   // This entails splitting the main partition.
   kEnabled,
 
+  // Same as kEnabled but without zapping quarantined objects.
+  kEnabledWithoutZapping,
+
   // BRP is disabled, but the main partition is split out, as if BRP was enabled
   // in the "previous slot" mode.
   kDisabledButSplitPartitions2Way,

src/base/allocator/partition_alloc_support.cc

@@ -50,33 +50,33 @@ namespace {
 
 #if BUILDFLAG(ENABLE_BASE_TRACING)
 constexpr const char* ScannerIdToTracingString(
-    internal::StatsCollector::ScannerId id) {
+    partition_alloc::internal::StatsCollector::ScannerId id) {
   switch (id) {
-    case internal::StatsCollector::ScannerId::kClear:
+    case partition_alloc::internal::StatsCollector::ScannerId::kClear:
       return "PCScan.Scanner.Clear";
-    case internal::StatsCollector::ScannerId::kScan:
+    case partition_alloc::internal::StatsCollector::ScannerId::kScan:
       return "PCScan.Scanner.Scan";
-    case internal::StatsCollector::ScannerId::kSweep:
+    case partition_alloc::internal::StatsCollector::ScannerId::kSweep:
       return "PCScan.Scanner.Sweep";
-    case internal::StatsCollector::ScannerId::kOverall:
+    case partition_alloc::internal::StatsCollector::ScannerId::kOverall:
       return "PCScan.Scanner";
-    case internal::StatsCollector::ScannerId::kNumIds:
+    case partition_alloc::internal::StatsCollector::ScannerId::kNumIds:
       __builtin_unreachable();
   }
 }
 
 constexpr const char* MutatorIdToTracingString(
-    internal::StatsCollector::MutatorId id) {
+    partition_alloc::internal::StatsCollector::MutatorId id) {
   switch (id) {
-    case internal::StatsCollector::MutatorId::kClear:
+    case partition_alloc::internal::StatsCollector::MutatorId::kClear:
       return "PCScan.Mutator.Clear";
-    case internal::StatsCollector::MutatorId::kScanStack:
+    case partition_alloc::internal::StatsCollector::MutatorId::kScanStack:
       return "PCScan.Mutator.ScanStack";
-    case internal::StatsCollector::MutatorId::kScan:
+    case partition_alloc::internal::StatsCollector::MutatorId::kScan:
       return "PCScan.Mutator.Scan";
-    case internal::StatsCollector::MutatorId::kOverall:
+    case partition_alloc::internal::StatsCollector::MutatorId::kOverall:
       return "PCScan.Mutator";
-    case internal::StatsCollector::MutatorId::kNumIds:
+    case partition_alloc::internal::StatsCollector::MutatorId::kNumIds:
       __builtin_unreachable();
   }
 }
@@ -85,8 +85,9 @@ constexpr const char* MutatorIdToTracingString(
 // Inject TRACE_EVENT_BEGIN/END, TRACE_COUNTER1, and UmaHistogramTimes.
 class StatsReporterImpl final : public partition_alloc::StatsReporter {
  public:
-  void ReportTraceEvent(internal::StatsCollector::ScannerId id,
+  void ReportTraceEvent(
-                        [[maybe_unused]] uint32_t tid,
+      partition_alloc::internal::StatsCollector::ScannerId id,
+      [[maybe_unused]] partition_alloc::internal::base::PlatformThreadId tid,
       int64_t start_time_ticks_internal_value,
       int64_t end_time_ticks_internal_value) override {
 #if BUILDFLAG(ENABLE_BASE_TRACING)
@@ -104,8 +105,9 @@ class StatsReporterImpl final : public partition_alloc::StatsReporter {
 #endif  // BUILDFLAG(ENABLE_BASE_TRACING)
   }
 
-  void ReportTraceEvent(internal::StatsCollector::MutatorId id,
+  void ReportTraceEvent(
-                        [[maybe_unused]] uint32_t tid,
+      partition_alloc::internal::StatsCollector::MutatorId id,
+      [[maybe_unused]] partition_alloc::internal::base::PlatformThreadId tid,
       int64_t start_time_ticks_internal_value,
       int64_t end_time_ticks_internal_value) override {
 #if BUILDFLAG(ENABLE_BASE_TRACING)
@@ -156,7 +158,7 @@ void RegisterPCScanStatsReporter() {
 
   DCHECK(!registered);
 
-  internal::PCScan::RegisterStatsReporter(&s_reporter);
+  partition_alloc::internal::PCScan::RegisterStatsReporter(&s_reporter);
   registered = true;
 }
 #endif  // defined(PA_ALLOW_PCSCAN)
@@ -289,6 +291,13 @@ std::map<std::string, std::string> ProposeSyntheticFinchTrials() {
         brp_group_name = "EnabledPrevSlot";
 #else
         brp_group_name = "EnabledBeforeAlloc";
+#endif
+        break;
+      case features::BackupRefPtrMode::kEnabledWithoutZapping:
+#if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
+        brp_group_name = "EnabledPrevSlotWithoutZapping";
+#else
+        brp_group_name = "EnabledBeforeAllocWithoutZapping";
 #endif
         break;
       case features::BackupRefPtrMode::kDisabledButSplitPartitions2Way:
@@ -413,7 +422,6 @@ absl::optional<debug::StackTrace> TakeStackTrace(uintptr_t id) {
 // This function is meant to be used only by Chromium developers, to list what
 // are all the dangling raw_ptr occurrences in a table.
 std::string ExtractDanglingPtrSignature(std::string stacktrace) {
-  LOG(ERROR) << stacktrace;
   std::vector<StringPiece> lines = SplitStringPiece(
       stacktrace, "\r\n", TRIM_WHITESPACE, SPLIT_WANT_NONEMPTY);
 
@@ -453,7 +461,7 @@ std::string ExtractDanglingPtrSignature(std::string stacktrace) {
   return std::string(caller.substr(function_start + 1));
 }
 
-void DanglingRawPtrReleased(uintptr_t id) {
+void DanglingRawPtrReleasedLogSignature(uintptr_t id) {
   // This is called from raw_ptr<>'s release operation. Making allocations is
   // allowed. In particular, symbolizing and printing the StackTraces may
   // allocate memory.
@@ -461,7 +469,6 @@ void DanglingRawPtrReleased(uintptr_t id) {
   debug::StackTrace stack_trace_release;
   absl::optional<debug::StackTrace> stack_trace_free = TakeStackTrace(id);
 
-  if (FeatureList::IsEnabled(features::kPartitionAllocDanglingPtrRecord)) {
   if (stack_trace_free) {
     LOG(ERROR) << StringPrintf(
         "[DanglingSignature]\t%s\t%s",
@@ -472,9 +479,15 @@ void DanglingRawPtrReleased(uintptr_t id) {
         "[DanglingSignature]\t%s\tmissing-stacktrace",
         ExtractDanglingPtrSignature(stack_trace_release.ToString()).c_str());
   }
-    return;
 }
 
+void DanglingRawPtrReleasedCrash(uintptr_t id) {
+  // This is called from raw_ptr<>'s release operation. Making allocations is
+  // allowed. In particular, symbolizing and printing the StackTraces may
+  // allocate memory.
+  debug::StackTrace stack_trace_release;
+  absl::optional<debug::StackTrace> stack_trace_free = TakeStackTrace(id);
+
   if (stack_trace_free) {
     LOG(ERROR) << StringPrintf(
         "Detected dangling raw_ptr with id=0x%016" PRIxPTR
@@ -506,8 +519,24 @@ void InstallDanglingRawPtrChecks() {
   // restarting the test executable.
   ClearDanglingRawPtrBuffer();
 
+  if (!FeatureList::IsEnabled(features::kPartitionAllocDanglingPtr)) {
+    partition_alloc::SetDanglingRawPtrDetectedFn([](uintptr_t) {});
+    partition_alloc::SetDanglingRawPtrReleasedFn([](uintptr_t) {});
+    return;
+  }
+
+  switch (features::kDanglingPtrModeParam.Get()) {
+    case features::DanglingPtrMode::kCrash:
       partition_alloc::SetDanglingRawPtrDetectedFn(DanglingRawPtrDetected);
-  partition_alloc::SetDanglingRawPtrReleasedFn(DanglingRawPtrReleased);
+      partition_alloc::SetDanglingRawPtrReleasedFn(DanglingRawPtrReleasedCrash);
+      break;
+
+    case features::DanglingPtrMode::kLogSignature:
+      partition_alloc::SetDanglingRawPtrDetectedFn(DanglingRawPtrDetected);
+      partition_alloc::SetDanglingRawPtrReleasedFn(
+          DanglingRawPtrReleasedLogSignature);
+      break;
+  }
 }
 
 // TODO(arthursonzogni): There might exist long lived dangling raw_ptr. If there

src/base/allocator/partition_allocator/BUILD.gn

@@ -277,8 +277,6 @@ target(partition_alloc_target_type, "partition_alloc") {
     ":debugging_buildflags",
     ":logging_buildflags",
     ":partition_alloc_buildflags",
-    "//base:synchronization_buildflags",
-    "//base:tracing_buildflags",
     "//build:branding_buildflags",
     "//build/config/compiler:compiler_buildflags",
   ]
@@ -324,73 +322,6 @@ target(partition_alloc_target_type, "partition_alloc") {
   }
 }
 
-source_set("test_support") {
-  sources = [
-    "extended_api.cc",
-    "extended_api.h",
-    "partition_alloc_base/threading/platform_thread_for_testing.h",
-  ]
-  if (is_posix) {
-    sources += [
-      "partition_alloc_base/threading/platform_thread_posix_for_testing.cc",
-    ]
-  }
-  if (is_fuchsia) {
-    sources += [
-      "partition_alloc_base/threading/platform_thread_fuchsia_for_testing.cc",
-      "partition_alloc_base/threading/platform_thread_posix_for_testing.cc",
-    ]
-  }
-  if (is_win) {
-    sources +=
-        [ "partition_alloc_base/threading/platform_thread_win_for_testing.cc" ]
-  }
-  if (is_mac || is_ios) {
-    sources +=
-        [ "partition_alloc_base/threading/platform_thread_mac_for_testing.mm" ]
-  }
-  if (is_linux || is_chromeos) {
-    sources += [
-      "partition_alloc_base/threading/platform_thread_linux_for_testing.cc",
-    ]
-  }
-  if (is_android) {
-    sources += [
-      "partition_alloc_base/threading/platform_thread_android_for_testing.cc",
-    ]
-  }
-  public_deps = [
-    ":chromecast_buildflags",
-    ":chromeos_buildflags",
-    ":debugging_buildflags",
-    ":logging_buildflags",
-    ":partition_alloc_buildflags",
-    "//base:synchronization_buildflags",
-    "//base:tracing_buildflags",
-    "//build:branding_buildflags",
-    "//build/config/compiler:compiler_buildflags",
-  ]
-  public_configs = []
-  if (is_fuchsia) {
-    public_deps += [
-      "//third_party/fuchsia-sdk/sdk/pkg/fit",
-      "//third_party/fuchsia-sdk/sdk/pkg/sync",
-      "//third_party/fuchsia-sdk/sdk/pkg/zx",
-    ]
-
-    # Needed for users of spinning_mutex.h, which for performance reasons,
-    # contains inlined calls to `libsync` inside the header file.
-    # It appends an entry to the "libs" section of the dependent target.
-    public_configs += [ ":fuchsia_sync_lib" ]
-  }
-  deps = [ "//base:base" ]
-
-  if (!is_debug) {
-    configs -= [ "//build/config/compiler:default_optimization" ]
-    configs += [ "//build/config/compiler:optimize_speed" ]
-  }
-}
-
 buildflag_header("partition_alloc_buildflags") {
   header = "partition_alloc_buildflags.h"
 

src/base/allocator/partition_allocator/OWNERS

@@ -1,3 +1,4 @@
 bartekn@chromium.org
 haraken@chromium.org
 lizeb@chromium.org
+tasak@google.com

src/base/allocator/partition_allocator/PartitionAlloc.md

@@ -21,6 +21,8 @@ paths of allocation and deallocation require very few (reasonably predictable)
 branches. The number of operations in the fast paths is minimal, leading to the
 possibility of inlining.
 
+![general architecture](./dot/layers.png)
+
 However, even the fast path isn't the fastest, because it requires taking
 a per-partition lock. Although we optimized the lock, there was still room for
 improvement; to this end, we introduced the thread cache.
@@ -102,6 +104,13 @@ partition page that holds metadata (32B struct per partition page).
       diagram).
 * Gray fill denotes guard pages (one partition page each at the head and tail
   of each super page).
+* In some configurations, PartitionAlloc stores more metadata than can
+  fit in the one system page at the front. These are the bitmaps for
+  StarScan and `MTECheckedPtr<T>`, and they are relegated to the head of
+  what would otherwise be usable space for slot spans. One, both, or
+  none of these bitmaps may be present, depending on build
+  configuration, runtime configuration, and type of allocation.
+  See [`SuperPagePayloadBegin()`][payload-start] for details.
 
 As allocation requests arrive, there is eventually a need to allocate a new slot
 span.
@@ -178,3 +187,4 @@ list.
 [PartitionPage]: https://source.chromium.org/chromium/chromium/src/+/main:base/allocator/partition_allocator/partition_page.h;l=314;drc=e5b03e85ea180d1d1ab0dec471c7fd5d1706a9e4
 [SlotSpanMetadata]: https://source.chromium.org/chromium/chromium/src/+/main:base/allocator/partition_allocator/partition_page.h;l=120;drc=e5b03e85ea180d1d1ab0dec471c7fd5d1706a9e4
 [SubsequentPageMetadata]: https://source.chromium.org/chromium/chromium/src/+/main:base/allocator/partition_allocator/partition_page.h;l=295;drc=e5b03e85ea180d1d1ab0dec471c7fd5d1706a9e4
+[payload-start]: https://source.chromium.org/chromium/chromium/src/+/35b2deed603dedd4abb37f204d516ed62aa2b85c:base/allocator/partition_allocator/partition_page.h;l=454

src/base/allocator/partition_allocator/address_pool_manager.h

@@ -21,13 +21,6 @@
 #include "base/allocator/partition_allocator/partition_lock.h"
 #include "build/build_config.h"
 
-namespace base {
-
-template <typename Type>
-struct LazyInstanceTraitsBase;
-
-}  // namespace base
-
 namespace partition_alloc {
 
 class AddressSpaceStatsDumper;
@@ -166,8 +159,6 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) AddressPoolManager {
 #endif  // defined(PA_HAS_64_BITS_POINTERS)
 
   static AddressPoolManager singleton_;
-
-  friend struct base::LazyInstanceTraitsBase<AddressPoolManager>;
 };
 
 PA_ALWAYS_INLINE pool_handle GetRegularPool() {
@@ -185,13 +176,4 @@ PA_ALWAYS_INLINE pool_handle GetConfigurablePool() {
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-using ::partition_alloc::internal::AddressPoolManager;
-using ::partition_alloc::internal::GetBRPPool;
-using ::partition_alloc::internal::GetConfigurablePool;
-using ::partition_alloc::internal::GetRegularPool;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_ADDRESS_POOL_MANAGER_H_

src/base/allocator/partition_allocator/address_pool_manager_types.h

@@ -11,12 +11,4 @@ using pool_handle = unsigned;
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::pool_handle;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_ADDRESS_POOL_MANAGER_TYPES_H_

src/base/allocator/partition_allocator/dot/layers.dot

@@ -0,0 +1,23 @@
+digraph G {
+  graph[bgcolor=transparent]
+  node[shape=box,style="filled,rounded",color=deepskyblue]
+
+  subgraph cluster_tc {
+    label = "Thread Cache"
+    rankdir = LR
+    {rank=same;TLS1,TLS2,TLSn}
+    TLS1->TLS2[style=invisible,dir=none]
+    TLS2->TLSn[style=dotted,dir=none]
+  }
+
+  subgraph cluster_central {
+    label = "Central Allocator (per-partition lock)"
+    fast[label="slot span freelists (fast path)"]
+    slow[label="slot span management (slow path)"]
+    # Forces slow path node beneath fast path node.
+    fast->slow[style=invisible,dir=none]
+  }
+
+  # Forces thread-external subgraph beneath thread cache subgraph.
+  TLS2->fast[style=invisible,dir=none]
+}

src/base/allocator/partition_allocator/dot/super-page.dot

@@ -21,6 +21,8 @@ digraph G {
         <TD BGCOLOR="darkgrey" HEIGHT="52"></TD>
         <TD PORT="metadata"></TD>
         <TD BGCOLOR="darkgrey" WIDTH="18"></TD>
+        <!-- Bitmaps -->
+        <TD WIDTH="100">Bitmaps(?)</TD>
         <!-- Several Slot Spans -->
         <TD PORT="red" BGCOLOR="crimson" WIDTH="119">3</TD>
         <TD PORT="green" BGCOLOR="palegreen" WIDTH="39">1</TD>
@@ -50,6 +52,8 @@ digraph G {
       <TR>
         <!-- Guard Page Metadata -->
         <TD BGCOLOR="darkgrey"> </TD>
+        <!-- Bitmaps Offset -->
+        <TD> B? </TD>
         <!-- Red Slot Span Metadata -->
         <TD BGCOLOR="crimson">v</TD>
         <TD BGCOLOR="crimson">+</TD>

src/base/allocator/partition_allocator/memory_reclaimer.h

@@ -71,12 +71,4 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) MemoryReclaimer {
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::MemoryReclaimer;
-
-}  // namespace base
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_MEMORY_RECLAIMER_H_

src/base/allocator/partition_allocator/page_allocator.h

@@ -329,35 +329,4 @@ PA_COMPONENT_EXPORT(PARTITION_ALLOC) size_t GetTotalMappedSize();
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::AllocPages;
-using ::partition_alloc::AllocPagesWithAlignOffset;
-using ::partition_alloc::DecommitAndZeroSystemPages;
-using ::partition_alloc::DecommitSystemPages;
-using ::partition_alloc::DecommittedMemoryIsAlwaysZeroed;
-using ::partition_alloc::DiscardSystemPages;
-using ::partition_alloc::FreePages;
-using ::partition_alloc::GetAllocPageErrorCode;
-using ::partition_alloc::GetTotalMappedSize;
-using ::partition_alloc::HasReservationForTesting;
-using ::partition_alloc::NextAlignedWithOffset;
-using ::partition_alloc::PageAccessibilityConfiguration;
-using ::partition_alloc::PageAccessibilityDisposition;
-using ::partition_alloc::PageTag;
-using ::partition_alloc::RecommitSystemPages;
-using ::partition_alloc::ReleaseReservation;
-using ::partition_alloc::ReserveAddressSpace;
-using ::partition_alloc::RoundDownToPageAllocationGranularity;
-using ::partition_alloc::RoundDownToSystemPage;
-using ::partition_alloc::RoundUpToPageAllocationGranularity;
-using ::partition_alloc::RoundUpToSystemPage;
-using ::partition_alloc::SetSystemPagesAccess;
-using ::partition_alloc::TryRecommitSystemPages;
-using ::partition_alloc::TrySetSystemPagesAccess;
-
-}  // namespace base
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PAGE_ALLOCATOR_H_

src/base/allocator/partition_allocator/page_allocator_constants.h

@@ -42,8 +42,8 @@ namespace partition_alloc::internal {
 // Use PageAllocationGranularity(), PageAllocationGranularityShift()
 // to initialize and retrieve these values safely.
 struct PageCharacteristics {
-  std::atomic<int> size;
+  std::atomic<size_t> size;
-  std::atomic<int> shift;
+  std::atomic<size_t> shift;
 };
 extern PageCharacteristics page_characteristics;
 
@@ -78,13 +78,14 @@ PageAllocationGranularityShift() {
 #elif defined(_MIPS_ARCH_LOONGSON)
   return 14;  // 16kB
 #elif BUILDFLAG(IS_APPLE) && defined(ARCH_CPU_64_BITS)
-  return vm_page_shift;
+  return static_cast<size_t>(vm_page_shift);
 #elif BUILDFLAG(IS_LINUX) && defined(ARCH_CPU_ARM64)
   // arm64 supports 4kb (shift = 12), 16kb (shift = 14), and 64kb (shift = 16)
   // page sizes. Retrieve from or initialize cache.
-  int shift = page_characteristics.shift.load(std::memory_order_relaxed);
+  size_t shift = page_characteristics.shift.load(std::memory_order_relaxed);
   if (PA_UNLIKELY(shift == 0)) {
-    shift = __builtin_ctz((int)PageAllocationGranularity());
+    shift = static_cast<size_t>(
+        __builtin_ctz((unsigned int)PageAllocationGranularity()));
     page_characteristics.shift.store(shift, std::memory_order_relaxed);
   }
   return shift;
@@ -102,9 +103,9 @@ PageAllocationGranularity() {
 #elif BUILDFLAG(IS_LINUX) && defined(ARCH_CPU_ARM64)
   // arm64 supports 4kb, 16kb, and 64kb page sizes. Retrieve from or
   // initialize cache.
-  int size = page_characteristics.size.load(std::memory_order_relaxed);
+  size_t size = page_characteristics.size.load(std::memory_order_relaxed);
   if (PA_UNLIKELY(size == 0)) {
-    size = getpagesize();
+    size = static_cast<size_t>(getpagesize());
     page_characteristics.size.store(size, std::memory_order_relaxed);
   }
   return size;

src/base/allocator/partition_allocator/partition_address_space.cc

@@ -17,7 +17,6 @@
 #include "base/allocator/partition_allocator/partition_alloc_check.h"
 #include "base/allocator/partition_allocator/partition_alloc_config.h"
 #include "base/allocator/partition_allocator/partition_alloc_constants.h"
-#include "base/allocator/partition_allocator/tagging.h"
 #include "build/build_config.h"
 
 #if BUILDFLAG(IS_IOS)
@@ -137,7 +136,7 @@ void PartitionAddressSpace::Init() {
   if (!setup_.regular_pool_base_address_)
     HandleGigaCageAllocFailure();
 #if defined(PA_USE_DYNAMICALLY_SIZED_GIGA_CAGE)
-  setup_.regular_pool_base_mask_ = ~(regular_pool_size - 1) & kMemTagUnmask;
+  setup_.regular_pool_base_mask_ = ~(regular_pool_size - 1);
 #endif
   PA_DCHECK(!(setup_.regular_pool_base_address_ & (regular_pool_size - 1)));
   setup_.regular_pool_ = AddressPoolManager::GetInstance().Add(
@@ -164,7 +163,7 @@ void PartitionAddressSpace::Init() {
     HandleGigaCageAllocFailure();
   setup_.brp_pool_base_address_ = base_address + kForbiddenZoneSize;
 #if defined(PA_USE_DYNAMICALLY_SIZED_GIGA_CAGE)
-  setup_.brp_pool_base_mask_ = ~(brp_pool_size - 1) & kMemTagUnmask;
+  setup_.brp_pool_base_mask_ = ~(brp_pool_size - 1);
 #endif
   PA_DCHECK(!(setup_.brp_pool_base_address_ & (brp_pool_size - 1)));
   setup_.brp_pool_ = AddressPoolManager::GetInstance().Add(

src/base/allocator/partition_allocator/partition_address_space.h

@@ -61,7 +61,6 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionAddressSpace {
 
   static PA_ALWAYS_INLINE std::pair<pool_handle, uintptr_t> GetPoolAndOffset(
       uintptr_t address) {
-    address = ::partition_alloc::internal::UnmaskPtr(address);
     // When USE_BACKUP_REF_PTR is off, BRP pool isn't used.
 #if !BUILDFLAG(USE_BACKUP_REF_PTR)
     PA_DCHECK(!IsInBRPPool(address));
@@ -155,8 +154,7 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionAddressSpace {
 
   static PA_ALWAYS_INLINE uintptr_t OffsetInBRPPool(uintptr_t address) {
     PA_DCHECK(IsInBRPPool(address));
-    return ::partition_alloc::internal::UnmaskPtr(address) -
+    return address - setup_.brp_pool_base_address_;
-           setup_.brp_pool_base_address_;
   }
 
   // PartitionAddressSpace is static_only class.
@@ -227,19 +225,12 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionAddressSpace {
 
 #if !defined(PA_USE_DYNAMICALLY_SIZED_GIGA_CAGE)
   // Masks used to easy determine belonging to a pool.
-  // On Arm, the top byte of each pointer is ignored (meaning there are
-  // effectively 256 versions of each valid pointer). 4 bits are used to store
-  // tags for Arm's Memory Tagging Extension (MTE). To ensure that tagged
-  // pointers are recognized as being in the pool, mask off the top byte with
-  // kMemTagUnmask.
   static constexpr uintptr_t kRegularPoolOffsetMask =
       static_cast<uintptr_t>(kRegularPoolSize) - 1;
-  static constexpr uintptr_t kRegularPoolBaseMask =
+  static constexpr uintptr_t kRegularPoolBaseMask = ~kRegularPoolOffsetMask;
-      ~kRegularPoolOffsetMask & kMemTagUnmask;
   static constexpr uintptr_t kBRPPoolOffsetMask =
       static_cast<uintptr_t>(kBRPPoolSize) - 1;
-  static constexpr uintptr_t kBRPPoolBaseMask =
+  static constexpr uintptr_t kBRPPoolBaseMask = ~kBRPPoolOffsetMask;
-      ~kBRPPoolOffsetMask & kMemTagUnmask;
 #endif  // !defined(PA_USE_DYNAMICALLY_SIZED_GIGA_CAGE)
 
   // This must be set to such a value that IsIn*Pool() always returns false when

src/base/allocator/partition_allocator/partition_alloc-inl.h

@@ -12,6 +12,7 @@
 #include "base/allocator/partition_allocator/partition_alloc_base/debug/debugging_buildflags.h"
 #include "base/allocator/partition_allocator/partition_ref_count.h"
 #include "base/allocator/partition_allocator/random.h"
+#include "base/allocator/partition_allocator/tagging.h"
 #include "build/build_config.h"
 
 // Prefetch *x into memory.
@@ -53,7 +54,7 @@ PA_ALWAYS_INLINE bool RandomPeriod() {
   static thread_local uint8_t counter = 0;
   if (PA_UNLIKELY(counter == 0)) {
     // It's OK to truncate this value.
-    counter = static_cast<uint8_t>(::partition_alloc::internal::RandomValue());
+    counter = static_cast<uint8_t>(RandomValue());
   }
   // If `counter` is 0, this will wrap. That is intentional and OK.
   counter--;
@@ -61,17 +62,22 @@ PA_ALWAYS_INLINE bool RandomPeriod() {
 }
 #endif  // !BUILDFLAG(PA_DCHECK_IS_ON)
 
+PA_ALWAYS_INLINE uintptr_t ObjectInnerPtr2Addr(const void* ptr) {
+  return UntagPtr(ptr);
+}
+PA_ALWAYS_INLINE uintptr_t ObjectPtr2Addr(const void* object) {
+  // TODO(bartekn): Check that |object| is indeed an object start.
+  return ObjectInnerPtr2Addr(object);
+}
+PA_ALWAYS_INLINE void* SlotStartAddr2Ptr(uintptr_t slot_start) {
+  // TODO(bartekn): Check that |slot_start| is indeed a slot start.
+  return TagAddr(slot_start);
+}
+PA_ALWAYS_INLINE uintptr_t SlotStartPtr2Addr(const void* slot_start) {
+  // TODO(bartekn): Check that |slot_start| is indeed a slot start.
+  return UntagPtr(slot_start);
+}
+
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::SecureMemset;
-#if !BUILDFLAG(PA_DCHECK_IS_ON)
-using ::partition_alloc::internal::RandomPeriod;
-#endif  // !BUILDFLAG(PA_DCHECK_IS_ON)
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_ALLOC_INL_H_

src/base/allocator/partition_allocator/partition_alloc.cc

@@ -70,6 +70,29 @@ void PartitionAllocGlobalInit(OomFunction on_out_of_memory) {
       internal::MaxSystemPagesPerRegularSlotSpan() <= 16,
       "System pages per slot span must be no greater than 16.");
 
+#if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
+  STATIC_ASSERT_OR_PA_CHECK(
+      internal::GetPartitionRefCountIndexMultiplierShift() <
+          std::numeric_limits<size_t>::max() / 2,
+      "Calculation in GetPartitionRefCountIndexMultiplierShift() must not "
+      "underflow.");
+  // Check that the GetPartitionRefCountIndexMultiplierShift() calculation is
+  // correct.
+  STATIC_ASSERT_OR_PA_CHECK(
+      (1 << internal::GetPartitionRefCountIndexMultiplierShift()) ==
+          (internal::SystemPageSize() /
+           (sizeof(internal::PartitionRefCount) *
+            (internal::kSuperPageSize / internal::SystemPageSize()))),
+      "Bitshift must match the intended multiplication.");
+  STATIC_ASSERT_OR_PA_CHECK(
+      ((sizeof(internal::PartitionRefCount) *
+        (internal::kSuperPageSize / internal::SystemPageSize()))
+       << internal::GetPartitionRefCountIndexMultiplierShift()) <=
+          internal::SystemPageSize(),
+      "PartitionRefCount Bitmap size must be smaller than or equal to "
+      "<= SystemPageSize().");
+#endif  // BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
+
   PA_DCHECK(on_out_of_memory);
   internal::g_oom_handling_function = on_out_of_memory;
 }

src/base/allocator/partition_allocator/partition_alloc.h

@@ -11,6 +11,36 @@
 #include "base/allocator/partition_allocator/partition_oom.h"
 #include "base/allocator/partition_allocator/partition_root.h"
 
+// *** HOUSEKEEPING RULES ***
+//
+// Throughout PartitionAlloc code, we avoid using generic variable names like
+// |ptr| or |address|, and prefer names like |object|, |slot_start|, instead.
+// This helps emphasize that terms like "object" and "slot" represent two
+// different worlds. "Slot" is an indivisible allocation unit, internal to
+// PartitionAlloc. It is generally represented as an address (uintptr_t), since
+// arithmetic operations on it aren't uncommon, and for that reason it isn't
+// MTE-tagged either. "Object" is the allocated memory that the app is given via
+// interfaces like Alloc(), Free(), etc. An object is fully contained within a
+// slot, and may be surrounded by internal PartitionAlloc structures or empty
+// space. Is is generally represented as a pointer to its beginning (most
+// commonly void*), and is MTE-tagged so it's safe to access.
+//
+// The best way to transition between these to worlds is via
+// PartitionRoot::ObjectToSlotStart() and ::SlotStartToObject(). These take care
+// of shifting between slot/object start, MTE-tagging/untagging and the cast for
+// you. There are cases where these functions are insufficient. Internal
+// PartitionAlloc structures, like free-list pointers, BRP ref-count, cookie,
+// etc. are located in-slot thus accessing them requires an MTE tag.
+// SlotStartPtr2Addr() and SlotStartAddr2Ptr() take care of this.
+// There are cases where we have to do pointer arithmetic on an object pointer
+// (like check belonging to a pool, etc.), in which case we want to strip MTE
+// tag. ObjectInnerPtr2Addr() and ObjectPtr2Addr() take care of that.
+//
+// Avoid using UntagPtr/Addr() and TagPtr/Addr() directly, if possible. And
+// definitely avoid using reinterpret_cast between uintptr_t and pointer worlds.
+// When you do, add a comment explaining why it's safe from the point of MTE
+// tagging.
+
 namespace partition_alloc {
 
 PA_COMPONENT_EXPORT(PARTITION_ALLOC)
@@ -43,14 +73,4 @@ using PartitionAllocator = internal::PartitionAllocator<internal::ThreadSafe>;
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::PartitionAllocator;
-using ::partition_alloc::PartitionAllocGlobalInit;
-using ::partition_alloc::PartitionAllocGlobalUninitForTesting;
-
-}  // namespace base
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_ALLOC_H_

src/base/allocator/partition_allocator/partition_alloc_base/bits.h

@@ -17,10 +17,6 @@
 #include "base/allocator/partition_allocator/partition_alloc_check.h"
 #include "build/build_config.h"
 
-#if defined(COMPILER_MSVC)
-#include <intrin.h>
-#endif
-
 namespace partition_alloc::internal::base::bits {
 
 // Returns true iff |value| is a power of 2.
@@ -75,85 +71,6 @@ inline T* AlignUp(T* ptr, size_t alignment) {
 //
 // C does not have an operator to do this, but fortunately the various
 // compilers have built-ins that map to fast underlying processor instructions.
-//
-// Prefer the clang path on Windows, as _BitScanReverse() and friends are not
-// constexpr.
-#if defined(COMPILER_MSVC) && !defined(__clang__)
-
-template <typename T, int bits = sizeof(T) * 8>
-PA_ALWAYS_INLINE
-    typename std::enable_if<std::is_unsigned<T>::value && sizeof(T) <= 4,
-                            int>::type
-    CountLeadingZeroBits(T x) {
-  static_assert(bits > 0, "invalid instantiation");
-  unsigned long index;
-  return PA_LIKELY(_BitScanReverse(&index, static_cast<uint32_t>(x)))
-             ? (31 - index - (32 - bits))
-             : bits;
-}
-
-template <typename T, int bits = sizeof(T) * 8>
-PA_ALWAYS_INLINE
-    typename std::enable_if<std::is_unsigned<T>::value && sizeof(T) == 8,
-                            int>::type
-    CountLeadingZeroBits(T x) {
-  static_assert(bits > 0, "invalid instantiation");
-  unsigned long index;
-// MSVC only supplies _BitScanReverse64 when building for a 64-bit target.
-#if defined(ARCH_CPU_64_BITS)
-  return PA_LIKELY(_BitScanReverse64(&index, static_cast<uint64_t>(x)))
-             ? (63 - index)
-             : 64;
-#else
-  uint32_t left = static_cast<uint32_t>(x >> 32);
-  if (PA_LIKELY(_BitScanReverse(&index, left)))
-    return 31 - index;
-
-  uint32_t right = static_cast<uint32_t>(x);
-  if (PA_LIKELY(_BitScanReverse(&index, right)))
-    return 63 - index;
-
-  return 64;
-#endif
-}
-
-template <typename T, int bits = sizeof(T) * 8>
-PA_ALWAYS_INLINE
-    typename std::enable_if<std::is_unsigned<T>::value && sizeof(T) <= 4,
-                            int>::type
-    CountTrailingZeroBits(T x) {
-  static_assert(bits > 0, "invalid instantiation");
-  unsigned long index;
-  return PA_LIKELY(_BitScanForward(&index, static_cast<uint32_t>(x))) ? index
-                                                                      : bits;
-}
-
-template <typename T, int bits = sizeof(T) * 8>
-PA_ALWAYS_INLINE
-    typename std::enable_if<std::is_unsigned<T>::value && sizeof(T) == 8,
-                            int>::type
-    CountTrailingZeroBits(T x) {
-  static_assert(bits > 0, "invalid instantiation");
-  unsigned long index;
-// MSVC only supplies _BitScanForward64 when building for a 64-bit target.
-#if defined(ARCH_CPU_64_BITS)
-  return PA_LIKELY(_BitScanForward64(&index, static_cast<uint64_t>(x))) ? index
-                                                                        : 64;
-#else
-  uint32_t right = static_cast<uint32_t>(x);
-  if (PA_LIKELY(_BitScanForward(&index, right)))
-    return index;
-
-  uint32_t left = static_cast<uint32_t>(x >> 32);
-  if (PA_LIKELY(_BitScanForward(&index, left)))
-    return 32 + index;
-
-  return 64;
-#endif
-}
-
-#elif defined(COMPILER_GCC) || defined(__clang__)
-
 // __builtin_clz has undefined behaviour for an input of 0, even though there's
 // clearly a return value that makes sense, and even though some processor clz
 // instructions have defined behaviour for 0. We could drop to raw __asm__ to
@@ -182,8 +99,6 @@ PA_ALWAYS_INLINE constexpr
                           : bits;
 }
 
-#endif
-
 // Returns the integer i such as 2^i <= n < 2^(i+1).
 //
 // There is a common `BitLength` function, which returns the number of bits

src/base/allocator/partition_allocator/partition_alloc_base/files/file_path.cc

@@ -10,7 +10,7 @@
 // on build time. Try not to raise this limit unless necessary. See
 // https://chromium.googlesource.com/chromium/src/+/HEAD/docs/wmax_tokens.md
 #ifndef NACL_TC_REV
-#pragma clang max_tokens_here 340000
+#pragma clang max_tokens_here 370000
 #endif
 
 #include <string.h>

src/base/allocator/partition_allocator/partition_alloc_base/migration_adapter.h

@@ -9,12 +9,6 @@ namespace base {
 
 class LapTimer;
 
-template <typename Type, typename Traits>
-class LazyInstance;
-
-template <typename Type>
-struct LazyInstanceTraitsBase;
-
 }  // namespace base
 
 namespace partition_alloc::internal::base {
@@ -22,8 +16,6 @@ namespace partition_alloc::internal::base {
 // TODO(https://crbug.com/1288247): Remove these 'using' declarations once
 // the migration to the new namespaces gets done.
 using ::base::LapTimer;
-using ::base::LazyInstance;
-using ::base::LazyInstanceTraitsBase;
 
 }  // namespace partition_alloc::internal::base
 

src/base/allocator/partition_allocator/partition_alloc_base/sys_byteorder.h

@@ -23,7 +23,7 @@
 namespace partition_alloc::internal::base {
 
 // Returns a value with all bytes in |x| swapped, i.e. reverses the endianness.
-inline uint16_t ByteSwap(uint16_t x) {
+inline constexpr uint16_t ByteSwap(uint16_t x) {
 #if defined(COMPILER_MSVC) && !defined(__clang__)
   return _byteswap_ushort(x);
 #else
@@ -31,7 +31,7 @@ inline uint16_t ByteSwap(uint16_t x) {
 #endif
 }
 
-inline uint32_t ByteSwap(uint32_t x) {
+inline constexpr uint32_t ByteSwap(uint32_t x) {
 #if defined(COMPILER_MSVC) && !defined(__clang__)
   return _byteswap_ulong(x);
 #else
@@ -69,21 +69,21 @@ inline constexpr uintptr_t ByteSwapUintPtrT(uintptr_t x) {
 
 // Converts the bytes in |x| from host order (endianness) to little endian, and
 // returns the result.
-inline uint16_t ByteSwapToLE16(uint16_t x) {
+inline constexpr uint16_t ByteSwapToLE16(uint16_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return x;
 #else
   return ByteSwap(x);
 #endif
 }
-inline uint32_t ByteSwapToLE32(uint32_t x) {
+inline constexpr uint32_t ByteSwapToLE32(uint32_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return x;
 #else
   return ByteSwap(x);
 #endif
 }
-inline uint64_t ByteSwapToLE64(uint64_t x) {
+inline constexpr uint64_t ByteSwapToLE64(uint64_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return x;
 #else
@@ -93,21 +93,21 @@ inline uint64_t ByteSwapToLE64(uint64_t x) {
 
 // Converts the bytes in |x| from network to host order (endianness), and
 // returns the result.
-inline uint16_t NetToHost16(uint16_t x) {
+inline constexpr uint16_t NetToHost16(uint16_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return ByteSwap(x);
 #else
   return x;
 #endif
 }
-inline uint32_t NetToHost32(uint32_t x) {
+inline constexpr uint32_t NetToHost32(uint32_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return ByteSwap(x);
 #else
   return x;
 #endif
 }
-inline uint64_t NetToHost64(uint64_t x) {
+inline constexpr uint64_t NetToHost64(uint64_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return ByteSwap(x);
 #else
@@ -117,21 +117,21 @@ inline uint64_t NetToHost64(uint64_t x) {
 
 // Converts the bytes in |x| from host to network order (endianness), and
 // returns the result.
-inline uint16_t HostToNet16(uint16_t x) {
+inline constexpr uint16_t HostToNet16(uint16_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return ByteSwap(x);
 #else
   return x;
 #endif
 }
-inline uint32_t HostToNet32(uint32_t x) {
+inline constexpr uint32_t HostToNet32(uint32_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return ByteSwap(x);
 #else
   return x;
 #endif
 }
-inline uint64_t HostToNet64(uint64_t x) {
+inline constexpr uint64_t HostToNet64(uint64_t x) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   return ByteSwap(x);
 #else

src/base/allocator/partition_allocator/partition_alloc_base/threading/platform_thread_posix_for_testing.cc

@@ -12,6 +12,7 @@
 #include <sys/time.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <memory>
 
 #include "base/allocator/partition_allocator/partition_alloc_base/logging.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/threading/platform_thread_internal_posix.h"

src/base/allocator/partition_allocator/partition_alloc_base/time/time.cc

@@ -10,7 +10,7 @@
 // time.h is a widely included header and its size impacts build time.
 // Try not to raise this limit unless necessary. See
 // https://chromium.googlesource.com/chromium/src/+/HEAD/docs/wmax_tokens.md
-#pragma clang max_tokens_here 390000
+#pragma clang max_tokens_here 490000
 #endif  // BUILDFLAG(IS_LINUX)
 
 #include <atomic>

src/base/allocator/partition_allocator/partition_alloc_base/time/time_win.cc

@@ -327,7 +327,7 @@ DWORD (*g_tick_function)(void) = &timeGetTimeWrapper;
 // "rollover" counter.
 union LastTimeAndRolloversState {
   // The state as a single 32-bit opaque value.
-  std::atomic<int32_t> as_opaque_32;
+  std::atomic<int32_t> as_opaque_32{0};
 
   // The state as usable values.
   struct {

src/base/allocator/partition_allocator/partition_alloc_constants.h

@@ -27,35 +27,30 @@ namespace partition_alloc {
 // Bit flag constants used as `flag` argument of PartitionRoot::AllocWithFlags,
 // AlignedAllocWithFlags, etc.
 struct AllocFlags {
-  // In order to support bit operations like `flag_a | flag_b`, the old-
+  static constexpr unsigned int kReturnNull = 1 << 0;
-  // fashioned enum (+ surrounding named struct) is used instead of enum class.
+  static constexpr unsigned int kZeroFill = 1 << 1;
-  enum : unsigned int {
-    kReturnNull = 1 << 0,
-    kZeroFill = 1 << 1,
   // Don't allow allocation override hooks. Override hooks are expected to
   // check for the presence of this flag and return false if it is active.
-    kNoOverrideHooks = 1 << 2,
+  static constexpr unsigned int kNoOverrideHooks = 1 << 2;
   // Never let a memory tool like ASan (if active) perform the allocation.
-    kNoMemoryToolOverride = 1 << 3,
+  static constexpr unsigned int kNoMemoryToolOverride = 1 << 3;
   // Don't allow any hooks (override or observers).
-    kNoHooks = 1 << 4,  // Internal only.
+  static constexpr unsigned int kNoHooks = 1 << 4;  // Internal.
   // If the allocation requires a "slow path" (such as allocating/committing a
   // new slot span), return nullptr instead. Note this makes all large
   // allocations return nullptr, such as direct-mapped ones, and even for
   // smaller ones, a nullptr value is common.
-    kFastPathOrReturnNull = 1 << 5,  // Internal only.
+  static constexpr unsigned int kFastPathOrReturnNull = 1 << 5;  // Internal.
 
-    kLastFlag = kFastPathOrReturnNull
+  static constexpr unsigned int kLastFlag = kFastPathOrReturnNull;
-  };
 };
 
 // Bit flag constants used as `flag` argument of PartitionRoot::FreeWithFlags.
 struct FreeFlags {
-  enum : unsigned int {
+  // See AllocFlags::kNoMemoryToolOverride.
-    kNoMemoryToolOverride = 1 << 0,  // See AllocFlags::kNoMemoryToolOverride.
+  static constexpr unsigned int kNoMemoryToolOverride = 1 << 0;
 
-    kLastFlag = kNoMemoryToolOverride
+  static constexpr unsigned int kLastFlag = kNoMemoryToolOverride;
-  };
 };
 
 namespace internal {
@@ -245,7 +240,7 @@ constexpr size_t kSuperPageShift = 21;  // 2 MiB
 constexpr size_t kSuperPageSize = 1 << kSuperPageShift;
 constexpr size_t kSuperPageAlignment = kSuperPageSize;
 constexpr size_t kSuperPageOffsetMask = kSuperPageAlignment - 1;
-constexpr size_t kSuperPageBaseMask = ~kSuperPageOffsetMask & kMemTagUnmask;
+constexpr size_t kSuperPageBaseMask = ~kSuperPageOffsetMask;
 
 // GigaCage is split into two pools, one which supports BackupRefPtr (BRP) and
 // one that doesn't.
@@ -283,14 +278,14 @@ static constexpr pool_handle kConfigurablePoolHandle = 3;
 constexpr size_t kMaxMemoryTaggingSize = 1024;
 
 #if defined(PA_HAS_MEMORY_TAGGING)
-// Returns whether the tag of |object| overflowed and the containing slot needs
+// Returns whether the tag of |object| overflowed, meaning the containing slot
-// to be moved to quarantine.
+// needs to be moved to quarantine.
 PA_ALWAYS_INLINE bool HasOverflowTag(void* object) {
   // The tag with which the slot is put to quarantine.
   constexpr uintptr_t kOverflowTag = 0x0f00000000000000uLL;
-  static_assert((kOverflowTag & ~kMemTagUnmask) != 0,
+  static_assert((kOverflowTag & kPtrTagMask) != 0,
                 "Overflow tag must be in tag bits");
-  return (reinterpret_cast<uintptr_t>(object) & ~kMemTagUnmask) == kOverflowTag;
+  return (reinterpret_cast<uintptr_t>(object) & kPtrTagMask) == kOverflowTag;
 }
 #endif  // defined(PA_HAS_MEMORY_TAGGING)
 

src/base/allocator/partition_allocator/partition_alloc_forward.h

@@ -25,16 +25,9 @@ namespace internal {
 // the second one 16. We could technically return something different for
 // malloc() and operator new(), but this would complicate things, and most of
 // our allocations are presumably coming from operator new() anyway.
-//
-// __STDCPP_DEFAULT_NEW_ALIGNMENT__ is C++17. As such, it is not defined on all
-// platforms, as Chrome's requirement is C++14 as of 2020.
-#if defined(__STDCPP_DEFAULT_NEW_ALIGNMENT__)
 constexpr size_t kAlignment =
     std::max(alignof(max_align_t),
              static_cast<size_t>(__STDCPP_DEFAULT_NEW_ALIGNMENT__));
-#else
-constexpr size_t kAlignment = alignof(max_align_t);
-#endif
 static_assert(kAlignment <= 16,
               "PartitionAlloc doesn't support a fundamental alignment larger "
               "than 16 bytes.");
@@ -62,14 +55,6 @@ using ThreadSafePartitionRoot = PartitionRoot<internal::ThreadSafe>;
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::PartitionRoot;
-
-}  // namespace base
-
 // From https://clang.llvm.org/docs/AttributeReference.html#malloc:
 //
 // The malloc attribute indicates that the function acts like a system memory

src/base/allocator/partition_allocator/partition_alloc_hooks.h

@@ -82,12 +82,4 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionAllocHooks {
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::PartitionAllocHooks;
-
-}  // namespace base
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_ALLOC_HOOKS_H_

src/base/allocator/partition_allocator/partition_bucket.cc

@@ -803,7 +803,7 @@ PA_ALWAYS_INLINE uintptr_t PartitionBucket<thread_safe>::AllocNewSuperPage(
                           PageAccessibilityConfiguration::kReadWrite,
                           PageAccessibilityDisposition::kRequireUpdate);
     }
-    ::base::internal::PCScan::RegisterNewSuperPage(root, super_page);
+    PCScan::RegisterNewSuperPage(root, super_page);
   }
 
   return payload;
@@ -883,9 +883,8 @@ PartitionBucket<thread_safe>::ProvisionMoreSlotsAndAllocOne(
   }
 
   if (PA_LIKELY(size <= kMaxMemoryTaggingSize)) {
-    // Ensure the memory tag of the return_slot is unguessable.
+    // Ensure the MTE-tag of the memory pointed by |return_slot| is unguessable.
-    return_slot =
+    TagMemoryRangeRandomly(return_slot, size);
-        ::partition_alloc::internal::TagMemoryRangeRandomly(return_slot, size);
   }
 #if defined(PA_USE_MTE_CHECKED_PTR_WITH_64_BITS_POINTERS)
   PartitionTagSetValue(return_slot, size, root->GetNewPartitionTag());
@@ -896,14 +895,20 @@ PartitionBucket<thread_safe>::ProvisionMoreSlotsAndAllocOne(
   uintptr_t next_slot_end = next_slot + size;
   size_t free_list_entries_added = 0;
   while (next_slot_end <= commit_end) {
+    void* next_slot_ptr;
     if (PA_LIKELY(size <= kMaxMemoryTaggingSize)) {
-      next_slot =
+      // Ensure the MTE-tag of the memory pointed by other provisioned slot is
-          ::partition_alloc::internal::TagMemoryRangeRandomly(next_slot, size);
+      // unguessable. They will be returned to the app as is, and the MTE-tag
+      // will only change upon calling Free().
+      next_slot_ptr = TagMemoryRangeRandomly(next_slot, size);
+    } else {
+      // No MTE-tagging for larger slots, just cast.
+      next_slot_ptr = reinterpret_cast<void*>(next_slot);
     }
 #if defined(PA_USE_MTE_CHECKED_PTR_WITH_64_BITS_POINTERS)
     PartitionTagSetValue(next_slot, size, root->GetNewPartitionTag());
 #endif  // defined(PA_USE_MTE_CHECKED_PTR_WITH_64_BITS_POINTERS)
-    auto* entry = PartitionFreelistEntry::EmplaceAndInitNull(next_slot);
+    auto* entry = PartitionFreelistEntry::EmplaceAndInitNull(next_slot_ptr);
     if (!slot_span->get_freelist_head()) {
       PA_DCHECK(!prev_entry);
       PA_DCHECK(!free_list_entries_added);

src/base/allocator/partition_allocator/partition_bucket.h

@@ -202,12 +202,4 @@ struct PartitionBucket {
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::PartitionBucket;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_BUCKET_H_

src/base/allocator/partition_allocator/partition_bucket_lookup.h

@@ -270,12 +270,4 @@ PA_ALWAYS_INLINE constexpr uint16_t BucketIndexLookup::GetIndexForDenserBuckets(
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::BucketIndexLookup;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_BUCKET_LOOKUP_H_

src/base/allocator/partition_allocator/partition_cookie.h

@@ -44,18 +44,4 @@ PA_ALWAYS_INLINE void PartitionCookieWriteValue(unsigned char* cookie_ptr) {}
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::kCookieSize;
-using ::partition_alloc::internal::kPartitionCookieSizeAdjustment;
-using ::partition_alloc::internal::PartitionCookieCheckValue;
-using ::partition_alloc::internal::PartitionCookieWriteValue;
-#if BUILDFLAG(PA_DCHECK_IS_ON)
-using ::partition_alloc::internal::kCookieValue;
-#endif  // BUILDFLAG(PA_DCHECK_IS_ON)
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_COOKIE_H_

src/base/allocator/partition_allocator/partition_direct_map_extent.h

@@ -72,13 +72,4 @@ PartitionDirectMapExtent<thread_safe>::FromSlotSpan(
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::PartitionDirectMapExtent;
-using ::partition_alloc::internal::PartitionDirectMapMetadata;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_DIRECT_MAP_EXTENT_H_

src/base/allocator/partition_allocator/partition_freelist_entry.h

@@ -41,6 +41,7 @@ class EncodedPartitionFreelistEntryPtr {
       std::nullptr_t)
       : encoded_(Transform(0)) {}
   explicit PA_ALWAYS_INLINE EncodedPartitionFreelistEntryPtr(void* ptr)
+      // The encoded pointer stays MTE-tagged.
       : encoded_(Transform(reinterpret_cast<uintptr_t>(ptr))) {}
 
   PA_ALWAYS_INLINE PartitionFreelistEntry* Decode() const {
@@ -117,11 +118,15 @@ class PartitionFreelistEntry {
   // Emplaces the freelist entry at the beginning of the given slot span, and
   // initializes it as null-terminated.
   static PA_ALWAYS_INLINE PartitionFreelistEntry* EmplaceAndInitNull(
-      uintptr_t slot_start) {
+      void* slot_start_tagged) {
-    auto* entry = new (reinterpret_cast<void*>(slot_start))
+    // |slot_start_tagged| is MTE-tagged.
-        PartitionFreelistEntry(nullptr);
+    auto* entry = new (slot_start_tagged) PartitionFreelistEntry(nullptr);
     return entry;
   }
+  static PA_ALWAYS_INLINE PartitionFreelistEntry* EmplaceAndInitNull(
+      uintptr_t slot_start) {
+    return EmplaceAndInitNull(SlotStartAddr2Ptr(slot_start));
+  }
 
   // Emplaces the freelist entry at the beginning of the given slot span, and
   // initializes it with the given |next| pointer, but encoded.
@@ -133,7 +138,7 @@ class PartitionFreelistEntry {
       uintptr_t slot_start,
       PartitionFreelistEntry* next) {
     auto* entry =
-        new (reinterpret_cast<void*>(slot_start)) PartitionFreelistEntry(next);
+        new (SlotStartAddr2Ptr(slot_start)) PartitionFreelistEntry(next);
     return entry;
   }
 
@@ -145,7 +150,7 @@ class PartitionFreelistEntry {
   static PA_ALWAYS_INLINE void EmplaceAndInitForTest(uintptr_t slot_start,
                                                      void* next,
                                                      bool make_shadow_match) {
-    new (reinterpret_cast<void*>(slot_start))
+    new (SlotStartAddr2Ptr(slot_start))
         PartitionFreelistEntry(next, make_shadow_match);
   }
 
@@ -174,7 +179,7 @@ class PartitionFreelistEntry {
     }
   }
 
-  PA_ALWAYS_INLINE void SetNext(PartitionFreelistEntry* ptr) {
+  PA_ALWAYS_INLINE void SetNext(PartitionFreelistEntry* entry) {
     // SetNext() is either called on the freelist head, when provisioning new
     // slots, or when GetNext() has been called before, no need to pass the
     // size.
@@ -182,15 +187,14 @@ class PartitionFreelistEntry {
     // Regular freelists always point to an entry within the same super page.
     //
     // This is most likely a PartitionAlloc bug if this triggers.
-    if (PA_UNLIKELY(
+    if (PA_UNLIKELY(entry &&
-            ptr &&
+                    (SlotStartPtr2Addr(this) & kSuperPageBaseMask) !=
-            (reinterpret_cast<uintptr_t>(this) & kSuperPageBaseMask) !=
+                        (SlotStartPtr2Addr(entry) & kSuperPageBaseMask))) {
-                (reinterpret_cast<uintptr_t>(ptr) & kSuperPageBaseMask))) {
       FreelistCorruptionDetected(0);
     }
 #endif  // BUILDFLAG(PA_DCHECK_IS_ON)
 
-    encoded_next_ = EncodedPartitionFreelistEntryPtr(ptr);
+    encoded_next_ = EncodedPartitionFreelistEntryPtr(entry);
 #if defined(PA_HAS_FREELIST_SHADOW_ENTRY)
     shadow_ = encoded_next_.Inverted();
 #endif
@@ -204,8 +208,7 @@ class PartitionFreelistEntry {
 #if defined(PA_HAS_FREELIST_SHADOW_ENTRY)
     shadow_ = 0;
 #endif
-    uintptr_t slot_start = reinterpret_cast<uintptr_t>(this);
+    return SlotStartPtr2Addr(this);
-    return slot_start;
   }
 
   PA_ALWAYS_INLINE constexpr bool IsEncodedNextPtrZero() const {
@@ -229,8 +232,8 @@ class PartitionFreelistEntry {
     //
     // Also, the lightweight UaF detection (pointer shadow) is checked.
 
-    uintptr_t here_address = reinterpret_cast<uintptr_t>(here);
+    uintptr_t here_address = SlotStartPtr2Addr(here);
-    uintptr_t next_address = reinterpret_cast<uintptr_t>(next);
+    uintptr_t next_address = SlotStartPtr2Addr(next);
 
 #if defined(PA_HAS_FREELIST_SHADOW_ENTRY)
     bool shadow_ptr_ok = here->encoded_next_.Inverted() == here->shadow_;
@@ -327,12 +330,4 @@ PA_ALWAYS_INLINE PartitionFreelistEntry* PartitionFreelistEntry::GetNext(
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::PartitionFreelistEntry;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_FREELIST_ENTRY_H_

src/base/allocator/partition_allocator/partition_oom.h

@@ -37,24 +37,4 @@ extern OomFunction g_oom_handling_function;
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::OomFunction;
-
-namespace internal {
-
-using ::partition_alloc::internal::g_oom_handling_function;
-using ::partition_alloc::internal::PartitionExcessiveAllocationSize;
-#if !defined(ARCH_CPU_64_BITS)
-using ::partition_alloc::internal::PartitionOutOfMemoryWithLargeVirtualSize;
-using ::partition_alloc::internal::
-    PartitionOutOfMemoryWithLotsOfUncommitedPages;
-#endif
-
-}  // namespace internal
-
-}  // namespace base
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_OOM_H_

src/base/allocator/partition_allocator/partition_page.cc

@@ -263,9 +263,7 @@ void SlotSpanMetadata<thread_safe>::SortFreelist() {
   for (PartitionFreelistEntry* head = freelist_head; head;
        head = head->GetNext(slot_size)) {
     ++num_free_slots;
-    size_t offset_in_slot_span = ::partition_alloc::internal::UnmaskPtr(
+    size_t offset_in_slot_span = SlotStartPtr2Addr(head) - slot_span_start;
-                                     reinterpret_cast<uintptr_t>(head)) -
-                                 slot_span_start;
     size_t slot_number = bucket->GetSlotNumber(offset_in_slot_span);
     PA_DCHECK(slot_number < num_provisioned_slots);
     free_slots[slot_number] = true;
@@ -280,9 +278,8 @@ void SlotSpanMetadata<thread_safe>::SortFreelist() {
     for (size_t slot_number = 0; slot_number < num_provisioned_slots;
          slot_number++) {
       if (free_slots[slot_number]) {
-        uintptr_t slot_address = ::partition_alloc::internal::RemaskPtr(
+        uintptr_t slot_start = slot_span_start + (slot_size * slot_number);
-            slot_span_start + (slot_size * slot_number));
+        auto* entry = PartitionFreelistEntry::EmplaceAndInitNull(slot_start);
-        auto* entry = PartitionFreelistEntry::EmplaceAndInitNull(slot_address);
 
         if (!head)
           head = entry;

src/base/allocator/partition_allocator/partition_page.h

@@ -502,7 +502,6 @@ SlotSpanMetadata<thread_safe>::ToSuperPageExtent() const {
 // surely never contain user data.
 PA_ALWAYS_INLINE bool IsWithinSuperPagePayload(uintptr_t address,
                                                bool with_quarantine) {
-  address = ::partition_alloc::internal::UnmaskPtr(address);
   // Quarantine can only be enabled for normal buckets in the current code.
   PA_DCHECK(!with_quarantine || IsManagedByNormalBuckets(address));
   uintptr_t super_page = address & kSuperPageBaseMask;
@@ -581,7 +580,6 @@ PA_ALWAYS_INLINE uintptr_t SlotSpanMetadata<thread_safe>::ToSlotSpanStart(
 template <bool thread_safe>
 PA_ALWAYS_INLINE SlotSpanMetadata<thread_safe>*
 SlotSpanMetadata<thread_safe>::FromAddr(uintptr_t address) {
-  address = ::partition_alloc::internal::UnmaskPtr(address);
   auto* page = PartitionPage<thread_safe>::FromAddr(address);
   PA_DCHECK(page->is_valid);
   // Partition pages in the same slot span share the same SlotSpanMetadata
@@ -611,9 +609,7 @@ SlotSpanMetadata<thread_safe>::FromSlotStart(uintptr_t slot_start) {
 #if BUILDFLAG(PA_DCHECK_IS_ON)
   // Checks that the pointer is a multiple of slot size.
   uintptr_t slot_span_start = ToSlotSpanStart(slot_span);
-  PA_DCHECK(!((::partition_alloc::internal::UnmaskPtr(slot_start) -
+  PA_DCHECK(!((slot_start - slot_span_start) % slot_span->bucket->slot_size));
-               ::partition_alloc::internal::UnmaskPtr(slot_span_start)) %
-              slot_span->bucket->slot_size));
 #endif  // BUILDFLAG(PA_DCHECK_IS_ON)
   return slot_span;
 }
@@ -625,16 +621,14 @@ SlotSpanMetadata<thread_safe>::FromSlotStart(uintptr_t slot_start) {
 template <bool thread_safe>
 PA_ALWAYS_INLINE SlotSpanMetadata<thread_safe>*
 SlotSpanMetadata<thread_safe>::FromObject(void* object) {
-  uintptr_t object_addr = PartitionRoot<thread_safe>::ObjectPtr2Addr(object);
+  uintptr_t object_addr = ObjectPtr2Addr(object);
   auto* slot_span = FromAddr(object_addr);
 #if BUILDFLAG(PA_DCHECK_IS_ON)
   // Checks that the object is exactly |extras_offset| away from a multiple of
   // slot size (i.e. from a slot start).
   uintptr_t slot_span_start = ToSlotSpanStart(slot_span);
   auto* root = PartitionRoot<thread_safe>::FromSlotSpan(slot_span);
-  PA_DCHECK((::partition_alloc::internal::UnmaskPtr(object_addr) -
+  PA_DCHECK((object_addr - slot_span_start) % slot_span->bucket->slot_size ==
-             ::partition_alloc::internal::UnmaskPtr(slot_span_start)) %
-                slot_span->bucket->slot_size ==
             root->flags.extras_offset);
 #endif  // BUILDFLAG(PA_DCHECK_IS_ON)
   return slot_span;
@@ -665,8 +659,7 @@ SlotSpanMetadata<thread_safe>::FromObjectInnerAddr(uintptr_t address) {
 template <bool thread_safe>
 PA_ALWAYS_INLINE SlotSpanMetadata<thread_safe>*
 SlotSpanMetadata<thread_safe>::FromObjectInnerPtr(void* ptr) {
-  return FromObjectInnerAddr(
+  return FromObjectInnerAddr(ObjectInnerPtr2Addr(ptr));
-      PartitionRoot<thread_safe>::ObjectInnerPtr2Addr(ptr));
 }
 
 template <bool thread_safe>
@@ -688,9 +681,14 @@ PA_ALWAYS_INLINE size_t SlotSpanMetadata<thread_safe>::GetRawSize() const {
 template <bool thread_safe>
 PA_ALWAYS_INLINE void SlotSpanMetadata<thread_safe>::SetFreelistHead(
     PartitionFreelistEntry* new_head) {
+#if BUILDFLAG(PA_DCHECK_IS_ON)
+  // |this| is in the metadata region, hence isn't MTE-tagged. Untag |new_head|
+  // as well.
+  uintptr_t new_head_untagged = UntagPtr(new_head);
   PA_DCHECK(!new_head ||
             (reinterpret_cast<uintptr_t>(this) & kSuperPageBaseMask) ==
-                (reinterpret_cast<uintptr_t>(new_head) & kSuperPageBaseMask));
+                (new_head_untagged & kSuperPageBaseMask));
+#endif
   freelist_head = new_head;
   // Inserted something new in the freelist, assume that it is not sorted
   // anymore.
@@ -720,7 +718,8 @@ PA_ALWAYS_INLINE void SlotSpanMetadata<thread_safe>::Free(uintptr_t slot_start)
   root->lock_.AssertAcquired();
 #endif
 
-  auto* entry = reinterpret_cast<internal::PartitionFreelistEntry*>(slot_start);
+  auto* entry = static_cast<internal::PartitionFreelistEntry*>(
+      SlotStartAddr2Ptr(slot_start));
   // Catches an immediate double free.
   PA_CHECK(entry != freelist_head);
   // Look for double free one level deeper in debug.
@@ -762,11 +761,10 @@ PA_ALWAYS_INLINE void SlotSpanMetadata<thread_safe>::AppendFreeList(
     size_t number_of_entries = 0;
     for (auto* entry = head; entry;
          entry = entry->GetNext(bucket->slot_size), ++number_of_entries) {
-      uintptr_t unmasked_entry = ::partition_alloc::internal::UnmaskPtr(
+      uintptr_t untagged_entry = UntagPtr(entry);
-          reinterpret_cast<uintptr_t>(entry));
       // Check that all entries belong to this slot span.
-      PA_DCHECK(ToSlotSpanStart(this) <= unmasked_entry);
+      PA_DCHECK(ToSlotSpanStart(this) <= untagged_entry);
-      PA_DCHECK(unmasked_entry <
+      PA_DCHECK(untagged_entry <
                 ToSlotSpanStart(this) + bucket->get_bytes_per_span());
     }
     PA_DCHECK(number_of_entries == number_of_freed);
@@ -902,23 +900,4 @@ void IterateSlotSpans(uintptr_t super_page,
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::AllocationStateMap;
-using ::partition_alloc::internal::CommittedStateBitmapSize;
-using ::partition_alloc::internal::IterateSlotSpans;
-using ::partition_alloc::internal::PartitionPage;
-using ::partition_alloc::internal::PartitionSuperPageExtentEntry;
-using ::partition_alloc::internal::PartitionSuperPageToExtent;
-using ::partition_alloc::internal::PartitionSuperPageToMetadataArea;
-using ::partition_alloc::internal::ReservedStateBitmapSize;
-using ::partition_alloc::internal::SlotSpanMetadata;
-using ::partition_alloc::internal::StateBitmapFromAddr;
-using ::partition_alloc::internal::SuperPageStateBitmap;
-using ::partition_alloc::internal::SuperPageStateBitmapAddr;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_PAGE_H_

src/base/allocator/partition_allocator/partition_ref_count.h

@@ -319,19 +319,49 @@ static constexpr size_t kInSlotRefCountBufferSize = sizeof(PartitionRefCount);
 constexpr size_t kPartitionRefCountOffsetAdjustment = 0;
 constexpr size_t kPartitionPastAllocationAdjustment = 0;
 
-constexpr size_t kPartitionRefCountIndexMultiplier =
+#if BUILDFLAG(ENABLE_DANGLING_RAW_PTR_CHECKS)
-    SystemPageSize() /
-    (sizeof(PartitionRefCount) * (kSuperPageSize / SystemPageSize()));
 
-static_assert((sizeof(PartitionRefCount) * (kSuperPageSize / SystemPageSize()) *
+#if defined(PA_REF_COUNT_CHECK_COOKIE) || \
-                   kPartitionRefCountIndexMultiplier <=
+    defined(PA_REF_COUNT_STORE_REQUESTED_SIZE)
-               SystemPageSize()),
+static constexpr size_t kPartitionRefCountSizeShift = 4;
-              "PartitionRefCount Bitmap size must be smaller than or equal to "
+#else   //  defined(PA_REF_COUNT_CHECK_COOKIE) ||
-              "<= SystemPageSize().");
+        //  defined(PA_REF_COUNT_STORE_REQUESTED_SIZE)
+static constexpr size_t kPartitionRefCountSizeShift = 3;
+#endif  //  defined(PA_REF_COUNT_CHECK_COOKIE) ||
+        //  defined(PA_REF_COUNT_STORE_REQUESTED_SIZE)
+
+#else  // BUILDFLAG(ENABLE_DANGLING_RAW_PTR_CHECKS)
+
+#if defined(PA_REF_COUNT_CHECK_COOKIE) && \
+    defined(PA_REF_COUNT_STORE_REQUESTED_SIZE)
+static constexpr size_t kPartitionRefCountSizeShift = 4;
+#elif defined(PA_REF_COUNT_CHECK_COOKIE) || \
+    defined(PA_REF_COUNT_STORE_REQUESTED_SIZE)
+static constexpr size_t kPartitionRefCountSizeShift = 3;
+#else
+static constexpr size_t kPartitionRefCountSizeShift = 2;
+#endif
+
+#endif  // defined(PA_REF_COUNT_CHECK_COOKIE)
+static_assert((1 << kPartitionRefCountSizeShift) == sizeof(PartitionRefCount));
+
+// We need one PartitionRefCount for each system page in a super page. They take
+// `x = sizeof(PartitionRefCount) * (kSuperPageSize / SystemPageSize())` space.
+// They need to fit into a system page of metadata as sparsely as possible to
+// minimize cache line sharing, hence we calculate a multiplier as
+// `SystemPageSize() / x`.
+//
+// The multiplier is expressed as a bitshift to optimize the code generation.
+// SystemPageSize() isn't always a constrexpr, in which case the compiler
+// wouldn't know it's a power of two. The equivalence of these calculations is
+// checked in PartitionAllocGlobalInit().
+static PAGE_ALLOCATOR_CONSTANTS_DECLARE_CONSTEXPR PA_ALWAYS_INLINE size_t
+GetPartitionRefCountIndexMultiplierShift() {
+  return SystemPageShift() * 2 - kSuperPageShift - kPartitionRefCountSizeShift;
+}
 
 PA_ALWAYS_INLINE PartitionRefCount* PartitionRefCountPointer(
     uintptr_t slot_start) {
-  PA_DCHECK(slot_start == ::partition_alloc::internal::RemaskPtr(slot_start));
 #if BUILDFLAG(PA_DCHECK_IS_ON) || BUILDFLAG(ENABLE_BACKUP_REF_PTR_SLOW_CHECKS)
   CheckThatSlotOffsetIsZero(slot_start);
 #endif
@@ -340,17 +370,20 @@ PA_ALWAYS_INLINE PartitionRefCount* PartitionRefCountPointer(
 #if BUILDFLAG(PA_DCHECK_IS_ON) || BUILDFLAG(ENABLE_BACKUP_REF_PTR_SLOW_CHECKS)
     PA_CHECK(refcount_address % alignof(PartitionRefCount) == 0);
 #endif
-    // Have to remask because the previous pointer's tag is unpredictable. There
+    // Have to MTE-tag, because the address is untagged, but lies within a slot
-    // could be a race condition though if the previous slot is freed/retagged
+    // area, which is protected by MTE.
-    // concurrently, so ideally the ref count should occupy its own MTE granule.
+    //
+    // There could be a race condition though if the previous slot is
+    // freed/retagged concurrently, so ideally the ref count should occupy its
+    // own MTE granule.
     // TODO(richard.townsend@arm.com): improve this.
-    return ::partition_alloc::internal::RemaskPtr(
+    return static_cast<PartitionRefCount*>(TagAddr(refcount_address));
-        reinterpret_cast<PartitionRefCount*>(refcount_address));
   } else {
+    // No need to tag, as the metadata region isn't protected by MTE.
     PartitionRefCount* bitmap_base = reinterpret_cast<PartitionRefCount*>(
         (slot_start & kSuperPageBaseMask) + SystemPageSize() * 2);
-    size_t index = ((slot_start & kSuperPageOffsetMask) >> SystemPageShift()) *
+    size_t index = ((slot_start & kSuperPageOffsetMask) >> SystemPageShift())
-                   kPartitionRefCountIndexMultiplier;
+                   << GetPartitionRefCountIndexMultiplierShift();
 #if BUILDFLAG(PA_DCHECK_IS_ON) || BUILDFLAG(ENABLE_BACKUP_REF_PTR_SLOW_CHECKS)
     PA_CHECK(sizeof(PartitionRefCount) * index <= SystemPageSize());
 #endif
@@ -375,7 +408,9 @@ PA_ALWAYS_INLINE PartitionRefCount* PartitionRefCountPointer(
 #if BUILDFLAG(PA_DCHECK_IS_ON) || BUILDFLAG(ENABLE_BACKUP_REF_PTR_SLOW_CHECKS)
   CheckThatSlotOffsetIsZero(slot_start);
 #endif
-  return reinterpret_cast<PartitionRefCount*>(slot_start);
+  // Have to MTE-tag, because the address is untagged, but lies within a slot
+  // area, which is protected by MTE.
+  return static_cast<PartitionRefCount*>(TagAddr(slot_start));
 }
 
 #endif  // BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
@@ -394,19 +429,4 @@ constexpr size_t kPartitionRefCountSizeAdjustment = kInSlotRefCountBufferSize;
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-#if BUILDFLAG(USE_BACKUP_REF_PTR)
-using ::partition_alloc::internal::kPartitionPastAllocationAdjustment;
-using ::partition_alloc::internal::PartitionRefCount;
-using ::partition_alloc::internal::PartitionRefCountPointer;
-#endif  // BUILDFLAG(USE_BACKUP_REF_PTR)
-using ::partition_alloc::internal::kInSlotRefCountBufferSize;
-using ::partition_alloc::internal::kPartitionRefCountOffsetAdjustment;
-using ::partition_alloc::internal::kPartitionRefCountSizeAdjustment;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_REF_COUNT_H_

src/base/allocator/partition_allocator/partition_root.cc

@@ -337,10 +337,8 @@ static size_t PartitionPurgeSlotSpan(
   // slots are not in use.
   for (PartitionFreelistEntry* entry = slot_span->get_freelist_head(); entry;
        /**/) {
-    size_t slot_index = (::partition_alloc::internal::UnmaskPtr(
+    size_t slot_index =
-                             reinterpret_cast<uintptr_t>(entry)) -
+        (SlotStartPtr2Addr(entry) - slot_span_start) / slot_size;
-                         slot_span_start) /
-                        slot_size;
     PA_DCHECK(slot_index < num_slots);
     slot_usage[slot_index] = 0;
 #if !BUILDFLAG(IS_WIN)
@@ -479,12 +477,11 @@ static void PartitionDumpSlotSpanStats(
 
   if (slot_span->CanStoreRawSize()) {
     stats_out->active_bytes += static_cast<uint32_t>(slot_span->GetRawSize());
-    stats_out->active_count += 1;
   } else {
     stats_out->active_bytes +=
         (slot_span->num_allocated_slots * stats_out->bucket_slot_size);
-    stats_out->active_count += slot_span->num_allocated_slots;
   }
+  stats_out->active_count += slot_span->num_allocated_slots;
 
   size_t slot_span_bytes_resident = RoundUpToSystemPage(
       (bucket_num_slots - slot_span->num_unprovisioned_slots) *
@@ -684,6 +681,10 @@ void PartitionRoot<thread_safe>::Init(PartitionOptions opts) {
 #if BUILDFLAG(USE_BACKUP_REF_PTR)
     flags.brp_enabled_ =
         opts.backup_ref_ptr == PartitionOptions::BackupRefPtr::kEnabled;
+    flags.brp_zapping_enabled_ =
+        opts.backup_ref_ptr_zapping ==
+        PartitionOptions::BackupRefPtrZapping::kEnabled;
+    PA_CHECK(!flags.brp_zapping_enabled_ || flags.brp_enabled_);
 #else
     PA_CHECK(opts.backup_ref_ptr == PartitionOptions::BackupRefPtr::kDisabled);
 #endif
@@ -828,6 +829,7 @@ bool PartitionRoot<thread_safe>::TryReallocInPlaceForDirectMap(
     internal::SlotSpanMetadata<thread_safe>* slot_span,
     size_t requested_size) {
   PA_DCHECK(slot_span->bucket->is_direct_mapped());
+  // Slot-span metadata isn't MTE-tagged.
   PA_DCHECK(
       internal::IsManagedByDirectMap(reinterpret_cast<uintptr_t>(slot_span)));
 
@@ -921,8 +923,7 @@ bool PartitionRoot<thread_safe>::TryReallocInPlaceForDirectMap(
 #if BUILDFLAG(PA_DCHECK_IS_ON)
   // Write a new trailing cookie.
   if (flags.allow_cookie) {
-    auto* object =
+    auto* object = static_cast<unsigned char*>(SlotStartToObject(slot_start));
-        reinterpret_cast<unsigned char*>(SlotStartToObject(slot_start));
     internal::PartitionCookieWriteValue(object +
                                         slot_span->GetUsableSize(this));
   }
@@ -933,17 +934,17 @@ bool PartitionRoot<thread_safe>::TryReallocInPlaceForDirectMap(
 
 template <bool thread_safe>
 bool PartitionRoot<thread_safe>::TryReallocInPlaceForNormalBuckets(
-    void* ptr,
+    void* object,
     SlotSpan* slot_span,
     size_t new_size) {
-  uintptr_t address = reinterpret_cast<uintptr_t>(ptr);
+  uintptr_t slot_start = ObjectToSlotStart(object);
-  PA_DCHECK(internal::IsManagedByNormalBuckets(address));
+  PA_DCHECK(internal::IsManagedByNormalBuckets(slot_start));
 
   // TODO: note that tcmalloc will "ignore" a downsizing realloc() unless the
   // new size is a significant percentage smaller. We could do the same if we
   // determine it is a win.
   if (AllocationCapacityFromRequestedSize(new_size) !=
-      AllocationCapacityFromPtr(ptr))
+      AllocationCapacityFromPtr(object))
     return false;
 
   // Trying to allocate |new_size| would use the same amount of underlying
@@ -951,7 +952,6 @@ bool PartitionRoot<thread_safe>::TryReallocInPlaceForNormalBuckets(
   // statistics (and cookie, if present).
   if (slot_span->CanStoreRawSize()) {
 #if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT) && BUILDFLAG(PA_DCHECK_IS_ON)
-    uintptr_t slot_start = ObjectToSlotStart(ptr);
     internal::PartitionRefCount* old_ref_count;
     if (brp_enabled()) {
       old_ref_count = internal::PartitionRefCountPointer(slot_start);
@@ -972,13 +972,12 @@ bool PartitionRoot<thread_safe>::TryReallocInPlaceForNormalBuckets(
     // Write a new trailing cookie only when it is possible to keep track
     // raw size (otherwise we wouldn't know where to look for it later).
     if (flags.allow_cookie) {
-      internal::PartitionCookieWriteValue(
+      internal::PartitionCookieWriteValue(static_cast<unsigned char*>(object) +
-          reinterpret_cast<unsigned char*>(address) +
                                           slot_span->GetUsableSize(this));
     }
 #endif  // BUILDFLAG(PA_DCHECK_IS_ON)
   }
-  return ptr;
+  return object;
 }
 
 template <bool thread_safe>
@@ -1176,6 +1175,12 @@ void PartitionRoot<thread_safe>::DumpStats(const char* partition_name,
         total_size_of_brp_quarantined_bytes.load(std::memory_order_relaxed);
     stats.total_brp_quarantined_count =
         total_count_of_brp_quarantined_slots.load(std::memory_order_relaxed);
+    stats.cumulative_brp_quarantined_bytes =
+        cumulative_size_of_brp_quarantined_bytes.load(
+            std::memory_order_relaxed);
+    stats.cumulative_brp_quarantined_count =
+        cumulative_count_of_brp_quarantined_slots.load(
+            std::memory_order_relaxed);
 #endif
 
     size_t direct_mapped_allocations_total_size = 0;

src/base/allocator/partition_allocator/partition_root.h

@@ -83,6 +83,14 @@
 
 namespace partition_alloc::internal {
 
+// This type trait verifies a type can be used as a pointer offset.
+//
+// We support pointer offsets in signed (ptrdiff_t) or unsigned (size_t) values.
+// Smaller types are also allowed.
+template <typename Z>
+static constexpr bool offset_type =
+    std::is_integral_v<Z> && sizeof(Z) <= sizeof(ptrdiff_t);
+
 static constexpr size_t kAllocInfoSize = 1 << 20;
 
 struct AllocInfo {
@@ -171,6 +179,11 @@ struct PartitionOptions {
     kEnabled,
   };
 
+  enum class BackupRefPtrZapping : uint8_t {
+    kDisabled,
+    kEnabled,
+  };
+
   enum class UseConfigurablePool : uint8_t {
     kNo,
     kIfAvailable,
@@ -182,12 +195,14 @@ struct PartitionOptions {
                              Quarantine quarantine,
                              Cookie cookie,
                              BackupRefPtr backup_ref_ptr,
+                             BackupRefPtrZapping backup_ref_ptr_zapping,
                              UseConfigurablePool use_configurable_pool)
       : aligned_alloc(aligned_alloc),
         thread_cache(thread_cache),
         quarantine(quarantine),
         cookie(cookie),
         backup_ref_ptr(backup_ref_ptr),
+        backup_ref_ptr_zapping(backup_ref_ptr_zapping),
         use_configurable_pool(use_configurable_pool) {}
 
   AlignedAlloc aligned_alloc;
@@ -195,6 +210,7 @@ struct PartitionOptions {
   Quarantine quarantine;
   Cookie cookie;
   BackupRefPtr backup_ref_ptr;
+  BackupRefPtrZapping backup_ref_ptr_zapping;
   UseConfigurablePool use_configurable_pool;
 };
 
@@ -241,6 +257,7 @@ struct PA_ALIGNAS(64) PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionRoot {
     bool allow_cookie;
 #if BUILDFLAG(USE_BACKUP_REF_PTR)
     bool brp_enabled_;
+    bool brp_zapping_enabled_;
 #endif
     bool use_configurable_pool;
 
@@ -305,6 +322,8 @@ struct PA_ALIGNAS(64) PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionRoot {
 #if BUILDFLAG(USE_BACKUP_REF_PTR)
   std::atomic<size_t> total_size_of_brp_quarantined_bytes{0};
   std::atomic<size_t> total_count_of_brp_quarantined_slots{0};
+  std::atomic<size_t> cumulative_size_of_brp_quarantined_bytes{0};
+  std::atomic<size_t> cumulative_count_of_brp_quarantined_slots{0};
 #endif
   // Slot span memory which has been provisioned, and is currently unused as
   // it's part of an empty SlotSpan. This is not clean memory, since it has
@@ -695,32 +714,21 @@ struct PA_ALIGNAS(64) PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionRoot {
     return size - flags.extras_size;
   }
 
-  PA_ALWAYS_INLINE void* SlotStartToObject(uintptr_t slot_start) const {
+  PA_ALWAYS_INLINE uintptr_t SlotStartToObjectAddr(uintptr_t slot_start) const {
-    // TODO(bartekn): Move MTE tagging here.
     // TODO(bartekn): Check that |slot_start| is indeed a slot start.
-    return reinterpret_cast<void*>(slot_start + flags.extras_offset);
+    return slot_start + flags.extras_offset;
+  }
+
+  PA_ALWAYS_INLINE void* SlotStartToObject(uintptr_t slot_start) const {
+    // TODO(bartekn): Check that |slot_start| is indeed a slot start.
+    return internal::TagAddr(SlotStartToObjectAddr(slot_start));
   }
 
   PA_ALWAYS_INLINE uintptr_t ObjectToSlotStart(void* object) const {
-    // TODO(bartekn): Move MTE untagging here.
+    return UntagPtr(object) - flags.extras_offset;
-    return reinterpret_cast<uintptr_t>(object) - flags.extras_offset;
     // TODO(bartekn): Check that the result is indeed a slot start.
   }
 
-  static PA_ALWAYS_INLINE uintptr_t ObjectInnerPtr2Addr(void* object) {
-    // TODO(bartekn): Add MTE untagging here.
-    return reinterpret_cast<uintptr_t>(object);
-  }
-  static PA_ALWAYS_INLINE uintptr_t ObjectPtr2Addr(void* object) {
-    // TODO(bartekn): Check that |object| is indeed an object start.
-    return ObjectInnerPtr2Addr(object);
-  }
-  static PA_ALWAYS_INLINE void* SlotStartAddr2Ptr(uintptr_t slot_start) {
-    // TODO(bartekn): Move MTE tagging here.
-    // TODO(bartekn): Check that |slot_start| is indeed a slot start.
-    return reinterpret_cast<void*>(slot_start);
-  }
-
   bool brp_enabled() const {
 #if BUILDFLAG(USE_BACKUP_REF_PTR)
     return flags.brp_enabled_;
@@ -729,6 +737,14 @@ struct PA_ALIGNAS(64) PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionRoot {
 #endif
   }
 
+  bool brp_zapping_enabled() const {
+#if BUILDFLAG(USE_BACKUP_REF_PTR)
+    return flags.brp_zapping_enabled_;
+#else
+    return false;
+#endif
+  }
+
   PA_ALWAYS_INLINE bool uses_configurable_pool() const {
     return flags.use_configurable_pool;
   }
@@ -794,7 +810,7 @@ struct PA_ALIGNAS(64) PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionRoot {
     return ret;
   }
 
-  // Allocates memory, without initializing extras.
+  // Allocates a memory slot, without initializing extras.
   //
   // - |flags| are as in AllocWithFlags().
   // - |raw_size| accommodates for extras on top of AllocWithFlags()'s
@@ -815,7 +831,7 @@ struct PA_ALIGNAS(64) PA_COMPONENT_EXPORT(PARTITION_ALLOC) PartitionRoot {
                                              bool* is_already_zeroed)
       PA_EXCLUSIVE_LOCKS_REQUIRED(lock_);
 
-  bool TryReallocInPlaceForNormalBuckets(void* ptr,
+  bool TryReallocInPlaceForNormalBuckets(void* object,
                                          SlotSpan* slot_span,
                                          size_t new_size);
   bool TryReallocInPlaceForDirectMap(
@@ -898,7 +914,8 @@ PartitionAllocGetDirectMapSlotStartInBRPPool(uintptr_t address) {
       PartitionDirectMapMetadata<ThreadSafe>::FromSlotSpan(slot_span);
   size_t padding_for_alignment =
       metadata->direct_map_extent.padding_for_alignment;
-  PA_DCHECK(padding_for_alignment == (page - first_page) * PartitionPageSize());
+  PA_DCHECK(padding_for_alignment ==
+            static_cast<size_t>(page - first_page) * PartitionPageSize());
   PA_DCHECK(slot_start ==
             reservation_start + PartitionPageSize() + padding_for_alignment);
 #endif  // BUILDFLAG(PA_DCHECK_IS_ON)
@@ -914,8 +931,6 @@ PartitionAllocGetDirectMapSlotStartInBRPPool(uintptr_t address) {
 // ref-count is in place for this allocation.
 PA_ALWAYS_INLINE uintptr_t
 PartitionAllocGetSlotStartInBRPPool(uintptr_t address) {
-  address = ::partition_alloc::internal::UnmaskPtr(address);
-
   // Adjust to support pointers right past the end of an allocation, which in
   // some cases appear to point outside the designated allocation slot.
   //
@@ -940,14 +955,11 @@ PartitionAllocGetSlotStartInBRPPool(uintptr_t address) {
   // Get the offset from the beginning of the slot span.
   uintptr_t slot_span_start =
       SlotSpanMetadata<ThreadSafe>::ToSlotSpanStart(slot_span);
-  PA_DCHECK(slot_span_start ==
-            ::partition_alloc::internal::UnmaskPtr(slot_span_start));
   size_t offset_in_slot_span = address - slot_span_start;
 
   auto* bucket = slot_span->bucket;
-  return ::partition_alloc::internal::RemaskPtr(
+  return slot_span_start +
-      slot_span_start +
+         bucket->slot_size * bucket->GetSlotNumber(offset_in_slot_span);
-      bucket->slot_size * bucket->GetSlotNumber(offset_in_slot_span));
 }
 
 // Checks whether a given address stays within the same allocation slot after
@@ -955,8 +967,9 @@ PartitionAllocGetSlotStartInBRPPool(uintptr_t address) {
 //
 // This isn't a general purpose function. The caller is responsible for ensuring
 // that the ref-count is in place for this allocation.
+template <typename Z, typename = std::enable_if_t<offset_type<Z>, void>>
 PA_ALWAYS_INLINE bool PartitionAllocIsValidPtrDelta(uintptr_t address,
-                                                    ptrdiff_t delta_in_bytes) {
+                                                    Z delta_in_bytes) {
   // Required for pointers right past an allocation. See
   // |PartitionAllocGetSlotStartInBRPPool()|.
   uintptr_t adjusted_address = address - kPartitionPastAllocationAdjustment;
@@ -974,11 +987,10 @@ PA_ALWAYS_INLINE bool PartitionAllocIsValidPtrDelta(uintptr_t address,
   // Double check that ref-count is indeed present.
   PA_DCHECK(root->brp_enabled());
 
-  void* object = root->SlotStartToObject(slot_start);
+  uintptr_t object_addr = root->SlotStartToObjectAddr(slot_start);
-  uintptr_t object_addr = PartitionRoot<ThreadSafe>::ObjectPtr2Addr(object);
+  uintptr_t new_address = address + static_cast<uintptr_t>(delta_in_bytes);
-  uintptr_t new_address = address + delta_in_bytes;
   return object_addr <= new_address &&
-         // We use "greater then or equal" below because we want to include
+         // We use "greater than or equal" below because we want to include
          // pointers right past the end of an allocation.
          new_address <= object_addr + slot_span->GetUsableSize(root);
 }
@@ -994,7 +1006,7 @@ PA_ALWAYS_INLINE void PartitionAllocFreeForRefCounting(uintptr_t slot_start) {
 
   // memset() can be really expensive.
 #if BUILDFLAG(PA_EXPENSIVE_DCHECKS_ARE_ON)
-  DebugMemset(reinterpret_cast<void*>(slot_start), kFreedByte,
+  DebugMemset(SlotStartAddr2Ptr(slot_start), kFreedByte,
               slot_span->GetUtilizedSlotSize()
 #if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
                   - sizeof(PartitionRefCount)
@@ -1021,9 +1033,8 @@ PartitionRoot<thread_safe>::AllocFromBucket(Bucket* bucket,
                                             size_t slot_span_alignment,
                                             size_t* usable_size,
                                             bool* is_already_zeroed) {
-  PA_DCHECK(
+  PA_DCHECK((slot_span_alignment >= internal::PartitionPageSize()) &&
-      (slot_span_alignment >= internal::PartitionPageSize()) &&
+            internal::base::bits::IsPowerOfTwo(slot_span_alignment));
-      partition_alloc::internal::base::bits::IsPowerOfTwo(slot_span_alignment));
   SlotSpan* slot_span = bucket->active_slot_spans_head;
   // There always must be a slot span on the active list (could be a sentinel).
   PA_DCHECK(slot_span);
@@ -1032,7 +1043,7 @@ PartitionRoot<thread_safe>::AllocFromBucket(Bucket* bucket,
   PA_DCHECK(!slot_span->marked_full);
 
   uintptr_t slot_start =
-      reinterpret_cast<uintptr_t>(slot_span->get_freelist_head());
+      internal::SlotStartPtr2Addr(slot_span->get_freelist_head());
   // Use the fast path when a slot is readily available on the free list of the
   // first active slot span. However, fall back to the slow path if a
   // higher-order alignment is requested, because an inner slot of an existing
@@ -1054,7 +1065,7 @@ PartitionRoot<thread_safe>::AllocFromBucket(Bucket* bucket,
     PA_DCHECK(!slot_span->CanStoreRawSize());
     PA_DCHECK(!slot_span->bucket->is_direct_mapped());
     void* entry = slot_span->PopForAlloc(bucket->slot_size);
-    PA_DCHECK(reinterpret_cast<uintptr_t>(entry) == slot_start);
+    PA_DCHECK(internal::SlotStartPtr2Addr(entry) == slot_start);
 
     PA_DCHECK(slot_span->bucket == bucket);
   } else {
@@ -1118,7 +1129,7 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooks(void* object) {
   // only cases where we don't would be delayed free() in PCScan, but |*object|
   // can be cold in cache.
   PA_PREFETCH(object);
-  uintptr_t object_addr = ObjectPtr2Addr(object);
+  uintptr_t object_addr = internal::ObjectPtr2Addr(object);
 
   // On Android, malloc() interception is more fragile than on other
   // platforms, as we use wrapped symbols. However, the GigaCage allows us to
@@ -1154,12 +1165,10 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooks(void* object) {
 #if defined(PA_HAS_MEMORY_TAGGING)
   const size_t slot_size = slot_span->bucket->slot_size;
   if (PA_LIKELY(slot_size <= internal::kMaxMemoryTaggingSize)) {
-    // TODO(bartekn): |slot_start| shouldn't have MTE tag.
+    internal::TagMemoryRangeIncrement(slot_start, slot_size);
-    slot_start = ::partition_alloc::internal::TagMemoryRangeIncrement(
-        slot_start, slot_size);
     // Incrementing the MTE-tag in the memory range invalidates the |object|'s
     // tag, so it must be retagged.
-    object = ::partition_alloc::internal::RemaskPtr(object);
+    object = internal::TagPtr(object);
   }
 #else
   // We are going to read from |*slot_span| in all branches, but haven't done it
@@ -1243,8 +1252,7 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooksImmediate(
   if (flags.allow_cookie) {
     // Verify the cookie after the allocated region.
     // If this assert fires, you probably corrupted memory.
-    internal::PartitionCookieCheckValue(
+    internal::PartitionCookieCheckValue(static_cast<unsigned char*>(object) +
-        reinterpret_cast<unsigned char*>(object) +
                                         slot_span->GetUsableSize(this));
   }
 #endif
@@ -1253,11 +1261,8 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooksImmediate(
   // default.
   if (PA_UNLIKELY(IsQuarantineEnabled())) {
     if (PA_LIKELY(internal::IsManagedByNormalBuckets(slot_start))) {
-      uintptr_t unmasked_slot_start =
-          ::partition_alloc::internal::UnmaskPtr(slot_start);
       // Mark the state in the state bitmap as freed.
-      internal::StateBitmapFromAddr(unmasked_slot_start)
+      internal::StateBitmapFromAddr(slot_start)->Free(slot_start);
-          ->Free(unmasked_slot_start);
     }
   }
 
@@ -1269,7 +1274,8 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooksImmediate(
     // If there are no more references to the allocation, it can be freed
     // immediately. Otherwise, defer the operation and zap the memory to turn
     // potential use-after-free issues into unexploitable crashes.
-    if (PA_UNLIKELY(!ref_count->IsAliveWithNoKnownRefs()))
+    if (PA_UNLIKELY(!ref_count->IsAliveWithNoKnownRefs() &&
+                    brp_zapping_enabled()))
       internal::SecureMemset(object, internal::kQuarantinedByte,
                              slot_span->GetUsableSize(this));
 
@@ -1278,6 +1284,10 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooksImmediate(
           slot_span->GetSlotSizeForBookkeeping(), std::memory_order_relaxed);
       total_count_of_brp_quarantined_slots.fetch_add(1,
                                                      std::memory_order_relaxed);
+      cumulative_size_of_brp_quarantined_bytes.fetch_add(
+          slot_span->GetSlotSizeForBookkeeping(), std::memory_order_relaxed);
+      cumulative_count_of_brp_quarantined_slots.fetch_add(
+          1, std::memory_order_relaxed);
       return;
     }
   }
@@ -1285,7 +1295,8 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooksImmediate(
 
   // memset() can be really expensive.
 #if BUILDFLAG(PA_EXPENSIVE_DCHECKS_ARE_ON)
-  internal::DebugMemset(SlotStartAddr2Ptr(slot_start), internal::kFreedByte,
+  internal::DebugMemset(internal::SlotStartAddr2Ptr(slot_start),
+                        internal::kFreedByte,
                         slot_span->GetUtilizedSlotSize()
 #if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
                             - sizeof(internal::PartitionRefCount)
@@ -1296,7 +1307,7 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::FreeNoHooksImmediate(
   // efficiency.
   if (PA_UNLIKELY(internal::RandomPeriod()) &&
       !IsDirectMappedBucket(slot_span->bucket)) {
-    internal::SecureMemset(SlotStartAddr2Ptr(slot_start), 0,
+    internal::SecureMemset(internal::SlotStartAddr2Ptr(slot_start), 0,
                            slot_span->GetUtilizedSlotSize()
 #if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
                                - sizeof(internal::PartitionRefCount)
@@ -1350,7 +1361,8 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::RawFree(uintptr_t slot_start,
   // RawFreeLocked()). This is intentional, as the thread cache is purged often,
   // and the memory has a consequence the memory has already been touched
   // recently (to link the thread cache freelist).
-  *reinterpret_cast<volatile uintptr_t*>(slot_start) = 0;
+  *static_cast<volatile uintptr_t*>(internal::SlotStartAddr2Ptr(slot_start)) =
+      0;
   // Note: even though we write to slot_start + sizeof(void*) as well, due to
   // alignment constraints, the two locations are always going to be in the same
   // OS page. No need to write to the second one as well.
@@ -1418,7 +1430,6 @@ PA_ALWAYS_INLINE void PartitionRoot<thread_safe>::RawFreeLocked(
 template <bool thread_safe>
 PA_ALWAYS_INLINE bool PartitionRoot<thread_safe>::IsValidSlotSpan(
     SlotSpan* slot_span) {
-  slot_span = ::partition_alloc::internal::UnmaskPtr(slot_span);
   PartitionRoot* root = FromSlotSpan(slot_span);
   return root->inverted_self == ~reinterpret_cast<uintptr_t>(root);
 }
@@ -1850,11 +1861,8 @@ PA_ALWAYS_INLINE void* PartitionRoot<thread_safe>::AllocWithFlagsNoHooks(
   // default.
   if (PA_UNLIKELY(is_quarantine_enabled)) {
     if (PA_LIKELY(internal::IsManagedByNormalBuckets(slot_start))) {
-      uintptr_t unmasked_slot_start =
-          ::partition_alloc::internal::UnmaskPtr(slot_start);
       // Mark the corresponding bits in the state bitmap as allocated.
-      internal::StateBitmapFromAddr(unmasked_slot_start)
+      internal::StateBitmapFromAddr(slot_start)->Allocate(slot_start);
-          ->Allocate(unmasked_slot_start);
     }
   }
 
@@ -1957,8 +1965,7 @@ PA_ALWAYS_INLINE void* PartitionRoot<thread_safe>::AlignedAllocWithFlags(
   // |alignment| is a power of two, but the compiler doesn't necessarily know
   // that. A regular % operation is very slow, make sure to use the equivalent,
   // faster form.
-  // No need to call ObjectPtr2Addr, because MTE untagging isn't necessary, as
+  // No need to MTE-untag, as it doesn't change alignment.
-  // it doesn't change alignment.
   PA_CHECK(!(reinterpret_cast<uintptr_t>(object) & (alignment - 1)));
 
   return object;
@@ -2021,30 +2028,12 @@ using ThreadSafePartitionRoot = PartitionRoot<internal::ThreadSafe>;
 static_assert(offsetof(ThreadSafePartitionRoot, lock_) ==
                   internal::kPartitionCachelineSize,
               "Padding is incorrect");
-}  // namespace partition_alloc
-
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::PartitionOptions;
-using ::partition_alloc::PurgeFlags;
-using ::partition_alloc::ThreadSafePartitionRoot;
-
-namespace internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::ScopedSyscallTimer;
 
 #if BUILDFLAG(USE_BACKUP_REF_PTR)
-using ::partition_alloc::internal::PartitionAllocFreeForRefCounting;
+// Usage in `raw_ptr.cc` is notable enough to merit a non-internal alias.
 using ::partition_alloc::internal::PartitionAllocGetSlotStartInBRPPool;
-using ::partition_alloc::internal::PartitionAllocIsValidPtrDelta;
 #endif  // BUILDFLAG(USE_BACKUP_REF_PTR)
 
-}  // namespace internal
+}  // namespace partition_alloc
-
-}  // namespace base
 
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_ROOT_H_

src/base/allocator/partition_allocator/partition_stats.h

@@ -59,6 +59,10 @@ struct PartitionMemoryStats {
       total_brp_quarantined_bytes;  // Total bytes that are quarantined by BRP.
   size_t total_brp_quarantined_count;  // Total number of slots that are
                                        // quarantined by BRP.
+  size_t cumulative_brp_quarantined_bytes;  // Cumulative bytes that are
+                                            // quarantined by BRP.
+  size_t cumulative_brp_quarantined_count;  // Cumulative number of slots that
+                                            // are quarantined by BRP.
 #endif
 
   bool has_thread_cache;
@@ -129,16 +133,4 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) SimplePartitionStatsDumper
 
 }  // namespace partition_alloc
 
-namespace base {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::PartitionBucketMemoryStats;
-using ::partition_alloc::PartitionMemoryStats;
-using ::partition_alloc::PartitionStatsDumper;
-using ::partition_alloc::SimplePartitionStatsDumper;
-using ::partition_alloc::ThreadCacheStats;
-
-}  // namespace base
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_STATS_H_

src/base/allocator/partition_allocator/partition_tag.h

@@ -48,12 +48,15 @@ PA_ALWAYS_INLINE PartitionTag* PartitionTagPointer(uintptr_t addr) {
   size_t offset_in_bitmap = offset_in_super_page >>
                             internal::tag_bitmap::kBytesPerPartitionTagShift
                                 << internal::tag_bitmap::kPartitionTagSizeShift;
+  // No need to tag, as the tag bitmap region isn't protected by MTE.
   return reinterpret_cast<PartitionTag*>(bitmap_base + offset_in_bitmap);
 }
 
 PA_ALWAYS_INLINE PartitionTag* PartitionTagPointer(const void* ptr) {
-  return PartitionTagPointer(
+  // Disambiguation: UntagPtr relates to hwardware MTE, and it strips the tag
-      internal::UnmaskPtr(reinterpret_cast<uintptr_t>(ptr)));
+  // from the pointer. Whereas, PartitionTagPointer relates to software MTE
+  // (i.e. MTECheckedPtr) and it returns a pointer to the tag in memory.
+  return PartitionTagPointer(UntagPtr(ptr));
 }
 
 namespace internal {
@@ -75,7 +78,10 @@ PA_ALWAYS_INLINE void PartitionTagSetValue(uintptr_t addr,
 PA_ALWAYS_INLINE void PartitionTagSetValue(void* ptr,
                                            size_t size,
                                            PartitionTag value) {
-  PartitionTagSetValue(reinterpret_cast<uintptr_t>(ptr), size, value);
+  // Disambiguation: UntagPtr relates to hwardware MTE, and it strips the tag
+  // from the pointer. Whereas, PartitionTagSetValue relates to software MTE
+  // (i.e. MTECheckedPtr) and it sets the in-memory tag.
+  PartitionTagSetValue(UntagPtr(ptr), size, value);
 }
 
 PA_ALWAYS_INLINE PartitionTag PartitionTagGetValue(void* ptr) {

src/base/allocator/partition_allocator/partition_tls.h

@@ -34,7 +34,7 @@ using PartitionTlsKey = pthread_key_t;
 #if BUILDFLAG(IS_MAC) && defined(ARCH_CPU_X86_64)
 namespace {
 
-PA_ALWAYS_INLINE void* FastTlsGet(intptr_t index) {
+PA_ALWAYS_INLINE void* FastTlsGet(PartitionTlsKey index) {
   // On macOS, pthread_getspecific() is in libSystem, so a call to it has to go
   // through PLT. However, and contrary to some other platforms, *all* TLS keys
   // are in a static array in the thread structure. So they are *always* at a
@@ -53,7 +53,10 @@ PA_ALWAYS_INLINE void* FastTlsGet(intptr_t index) {
   // This function is essentially inlining the content of pthread_getspecific()
   // here.
   intptr_t result;
-  asm("movq %%gs:(,%1,8), %0;" : "=r"(result) : "r"(index));
+  static_assert(sizeof index <= sizeof(intptr_t));
+  asm("movq %%gs:(,%1,8), %0;"
+      : "=r"(result)
+      : "r"(static_cast<intptr_t>(index)));
 
   return reinterpret_cast<void*>(result);
 }
@@ -140,18 +143,4 @@ PA_ALWAYS_INLINE void PartitionTlsSet(PartitionTlsKey key, void* value) {
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::PartitionTlsCreate;
-using ::partition_alloc::internal::PartitionTlsGet;
-using ::partition_alloc::internal::PartitionTlsKey;
-using ::partition_alloc::internal::PartitionTlsSet;
-#if BUILDFLAG(IS_WIN)
-using ::partition_alloc::internal::PartitionTlsSetOnDllProcessDetach;
-#endif  // BUILDFLAG(IS_WIN)
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_PARTITION_TLS_H_

src/base/allocator/partition_allocator/reservation_offset_table.h

@@ -146,7 +146,6 @@ PA_ALWAYS_INLINE const uint16_t* GetReservationOffsetTableEnd(
 PA_ALWAYS_INLINE uint16_t* ReservationOffsetPointer(uintptr_t address) {
 #if defined(PA_HAS_64_BITS_POINTERS)
   // In 64-bit mode, find the owning Pool and compute the offset from its base.
-  address = ::partition_alloc::internal::UnmaskPtr(address);
   auto [pool, offset] = GetPoolAndOffset(address);
   return ReservationOffsetPointer(pool, offset);
 #else
@@ -254,21 +253,4 @@ PA_ALWAYS_INLINE bool IsManagedByNormalBucketsOrDirectMap(uintptr_t address) {
 
 }  // namespace partition_alloc::internal
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::internal::GetDirectMapReservationStart;
-using ::partition_alloc::internal::GetReservationOffsetTable;
-using ::partition_alloc::internal::GetReservationOffsetTableEnd;
-using ::partition_alloc::internal::IsManagedByDirectMap;
-using ::partition_alloc::internal::IsManagedByNormalBuckets;
-using ::partition_alloc::internal::IsManagedByNormalBucketsOrDirectMap;
-using ::partition_alloc::internal::IsReservationStart;
-using ::partition_alloc::internal::kOffsetTagNormalBuckets;
-using ::partition_alloc::internal::kOffsetTagNotAllocated;
-using ::partition_alloc::internal::ReservationOffsetPointer;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_RESERVATION_OFFSET_TABLE_H_

src/base/allocator/partition_allocator/starscan/metadata_allocator.cc

@@ -17,6 +17,7 @@ constexpr PartitionOptions kConfig{
     PartitionOptions::Quarantine::kDisallowed,
     PartitionOptions::Cookie::kAllowed,
     PartitionOptions::BackupRefPtr::kDisabled,
+    PartitionOptions::BackupRefPtrZapping::kDisabled,
     PartitionOptions::UseConfigurablePool::kNo,
 };
 }  // namespace

src/base/allocator/partition_allocator/starscan/metadata_allocator.h

@@ -80,16 +80,4 @@ struct PCScanMetadataDeleter final {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove these when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::AllocatedOnPCScanMetadataPartition;
-using ::partition_alloc::internal::MakePCScanMetadata;
-using ::partition_alloc::internal::MetadataAllocator;
-using ::partition_alloc::internal::PCScanMetadataAllocator;
-using ::partition_alloc::internal::PCScanMetadataDeleter;
-using ::partition_alloc::internal::ReinitPCScanMetadataAllocatorForTesting;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_METADATA_ALLOCATOR_H_

src/base/allocator/partition_allocator/starscan/pcscan.h

@@ -247,15 +247,12 @@ PA_ALWAYS_INLINE void PCScan::MoveToQuarantine(void* object,
     SecureMemset(object, 0, usable_size);
   }
 
-  // TODO(bartekn): Remove MTE untagging, once its done in the caller.
+  auto* state_bitmap = StateBitmapFromAddr(slot_start);
-  uintptr_t unmasked_slot_start =
-      ::partition_alloc::internal::UnmaskPtr(slot_start);
-  auto* state_bitmap = StateBitmapFromAddr(unmasked_slot_start);
 
   // Mark the state in the state bitmap as quarantined. Make sure to do it after
   // the clearing to avoid racing with *Scan Sweeper.
   [[maybe_unused]] const bool succeeded =
-      state_bitmap->Quarantine(unmasked_slot_start, instance.epoch());
+      state_bitmap->Quarantine(slot_start, instance.epoch());
 #if PA_STARSCAN_EAGER_DOUBLE_FREE_DETECTION_ENABLED
   if (PA_UNLIKELY(!succeeded))
     DoubleFreeAttempt();
@@ -281,10 +278,4 @@ inline PCScanScheduler& PCScan::scheduler() {
 }  // namespace internal
 }  // namespace partition_alloc
 
-// TODO(crbug.com/1288247): Remove this when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::PCScan;
-
-}  // namespace base::internal
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_PCSCAN_H_

src/base/allocator/partition_allocator/starscan/pcscan_internal.cc

@@ -142,7 +142,6 @@ class QuarantineCardTable final {
   // slots. May return false positives for but should never return false
   // negatives, as otherwise this breaks security.
   PA_ALWAYS_INLINE bool IsQuarantined(uintptr_t address) const {
-    address = ::partition_alloc::internal::UnmaskPtr(address);
     const size_t byte = Byte(address);
     PA_SCAN_DCHECK(byte < bytes_.size());
     return bytes_[byte];
@@ -653,6 +652,7 @@ PA_SCAN_INLINE AllocationStateMap* PCScanTask::TryFindScannerBitmapForPointer(
 PA_SCAN_INLINE size_t
 PCScanTask::TryMarkSlotInNormalBuckets(uintptr_t maybe_ptr) const {
   // Check if |maybe_ptr| points somewhere to the heap.
+  // The caller has to make sure that |maybe_ptr| isn't MTE-tagged.
   auto* state_map = TryFindScannerBitmapForPointer(maybe_ptr);
   if (!state_map)
     return 0;
@@ -722,8 +722,7 @@ void PCScanTask::ClearQuarantinedSlotsAndPrepareCardTable() {
       // ScanPartitions.
       const size_t size = slot_span->GetUsableSize(root);
       if (clear_type == PCScan::ClearType::kLazy) {
-        void* object = ::partition_alloc::internal::RemaskPtr(
+        void* object = root->SlotStartToObject(slot_start);
-            root->SlotStartToObject(slot_start));
         memset(object, 0, size);
       }
 #if PA_STARSCAN_USE_CARD_TABLE
@@ -774,9 +773,10 @@ class PCScanScanLoop final : public ScanLoop<PCScanScanLoop> {
   }
 #endif  // defined(PA_HAS_64_BITS_POINTERS)
 
-  PA_SCAN_INLINE void CheckPointer(uintptr_t maybe_ptr) {
+  PA_SCAN_INLINE void CheckPointer(uintptr_t maybe_ptr_maybe_tagged) {
-    quarantine_size_ += task_.TryMarkSlotInNormalBuckets(
+    // |maybe_ptr| may have an MTE tag, so remove it first.
-        ::partition_alloc::internal::UnmaskPtr(maybe_ptr));
+    quarantine_size_ +=
+        task_.TryMarkSlotInNormalBuckets(UntagAddr(maybe_ptr_maybe_tagged));
   }
 
   const PCScanTask& task_;
@@ -937,8 +937,6 @@ void UnmarkInCardTable(uintptr_t slot_start,
     SlotSpanMetadata<ThreadSafe>* slot_span,
     uintptr_t slot_start) {
   void* object = root->SlotStartToObject(slot_start);
-  // TODO(bartekn): Move MTE masking into SlotStartToObject.
-  object = ::partition_alloc::internal::RemaskPtr(object);
   root->FreeNoHooksImmediate(object, slot_span, slot_start);
   UnmarkInCardTable(slot_start, slot_span);
   return slot_span->bucket->slot_size;
@@ -1003,8 +1001,7 @@ void UnmarkInCardTable(uintptr_t slot_start,
 
   const auto bitmap_iterator = [&](uintptr_t slot_start) {
     SlotSpan* current_slot_span = SlotSpan::FromSlotStart(slot_start);
-    auto* entry = PartitionFreelistEntry::EmplaceAndInitNull(
+    auto* entry = PartitionFreelistEntry::EmplaceAndInitNull(slot_start);
-        ::partition_alloc::internal::RemaskPtr(slot_start));
 
     if (current_slot_span != previous_slot_span) {
       // We started scanning a new slot span. Flush the accumulated freelist to

src/base/allocator/partition_allocator/starscan/pcscan_internal.h

@@ -20,11 +20,8 @@
 #include "base/allocator/partition_allocator/starscan/starscan_fwd.h"
 #include "base/allocator/partition_allocator/starscan/write_protector.h"
 
-// TODO(crbug.com/1288247): Remove this when migration is complete.
 namespace partition_alloc::internal {
 
-class StarScanSnapshot;
-
 class PCScanTask;
 
 // Internal PCScan singleton. The separation between frontend and backend is
@@ -111,7 +108,7 @@ class PCScanInternal final {
 
  private:
   friend internal::base::NoDestructor<PCScanInternal>;
-  friend class partition_alloc::internal::StarScanSnapshot;
+  friend class StarScanSnapshot;
 
   using StackTops = std::unordered_map<
       internal::base::PlatformThreadId,
@@ -149,11 +146,4 @@ class PCScanInternal final {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove this when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::PCScanInternal;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_PCSCAN_INTERNAL_H_

src/base/allocator/partition_allocator/starscan/pcscan_scheduling.cc

@@ -33,8 +33,7 @@ void PCScanSchedulingBackend::EnableScheduling() {
   scheduling_enabled_.store(true, std::memory_order_relaxed);
   // Check if *Scan needs to be run immediately.
   if (NeedsToImmediatelyScan())
-    ::base::internal::PCScan::PerformScan(
+    PCScan::PerformScan(PCScan::InvocationMode::kNonBlocking);
-        ::base::internal::PCScan::InvocationMode::kNonBlocking);
 }
 
 size_t PCScanSchedulingBackend::ScanStarted() {

src/base/allocator/partition_allocator/starscan/pcscan_scheduling.h

@@ -198,14 +198,4 @@ bool PCScanScheduler::AccountFreed(size_t size) {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove these when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::LimitBackend;
-using ::partition_alloc::internal::MUAwareTaskBasedBackend;
-using ::partition_alloc::internal::PCScanScheduler;
-using ::partition_alloc::internal::QuarantineData;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_PCSCAN_SCHEDULING_H_

src/base/allocator/partition_allocator/starscan/raceful_worklist.h

@@ -139,9 +139,4 @@ void RacefulWorklist<T>::RandomizedView::Visit(Function f) {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove these when migration is complete.
-namespace base::internal {
-using ::partition_alloc::internal::RacefulWorklist;
-}
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_RACEFUL_WORKLIST_H_

src/base/allocator/partition_allocator/starscan/scan_loop.h

@@ -12,6 +12,7 @@
 #include "base/allocator/partition_allocator/partition_alloc_check.h"
 #include "base/allocator/partition_allocator/partition_alloc_config.h"
 #include "base/allocator/partition_allocator/starscan/starscan_fwd.h"
+#include "base/allocator/partition_allocator/tagging.h"
 #include "build/build_config.h"
 
 #if defined(ARCH_CPU_X86_64)
@@ -92,7 +93,9 @@ void ScanLoop<Derived>::RunUnvectorized(uintptr_t begin, uintptr_t end) {
   PA_SCAN_DCHECK(!(begin % sizeof(uintptr_t)));
   PA_SCAN_DCHECK(!(end % sizeof(uintptr_t)));
 #if defined(PA_HAS_64_BITS_POINTERS)
-  const uintptr_t mask = Derived::CageMask();
+  // If the read value is a pointer into the PA region, it's likely
+  // MTE-tagged. Piggyback on |mask| to untag, for efficiency.
+  const uintptr_t mask = Derived::CageMask() & kPtrUntagMask;
   const uintptr_t base = Derived::CageBase();
 #endif
   for (; begin < end; begin += sizeof(uintptr_t)) {
@@ -126,7 +129,10 @@ __attribute__((target("avx2"))) void ScanLoop<Derived>::RunAVX2(uintptr_t begin,
   // vmovdqa (_mm256_load_si256) is twice smaller (0.25) than that of vmovapd
   // (_mm256_load_pd).
   const __m256i vbase = _mm256_set1_epi64x(derived().CageBase());
-  const __m256i cage_mask = _mm256_set1_epi64x(derived().CageMask());
+  // If the read value is a pointer into the PA region, it's likely
+  // MTE-tagged. Piggyback on |cage_mask| to untag, for efficiency.
+  const __m256i cage_mask =
+      _mm256_set1_epi64x(derived().CageMask() & kPtrUntagMask);
 
   static_assert(sizeof(__m256i) == kBytesInVector);
   for (; begin <= (end - kBytesInVector); begin += kBytesInVector) {
@@ -162,7 +168,10 @@ __attribute__((target("sse4.1"))) void ScanLoop<Derived>::RunSSE4(
   static constexpr size_t kBytesInVector = kWordsInVector * sizeof(uintptr_t);
   PA_SCAN_DCHECK(!(begin % kAlignmentRequirement));
   const __m128i vbase = _mm_set1_epi64x(derived().CageBase());
-  const __m128i cage_mask = _mm_set1_epi64x(derived().CageMask());
+  // If the read value is a pointer into the PA region, it's likely
+  // MTE-tagged. Piggyback on |cage_mask| to untag, for efficiency.
+  const __m128i cage_mask =
+      _mm_set1_epi64x(derived().CageMask() & kPtrUntagMask);
 
   static_assert(sizeof(__m128i) == kBytesInVector);
   for (; begin <= (end - kBytesInVector); begin += kBytesInVector) {
@@ -200,7 +209,10 @@ void ScanLoop<Derived>::RunNEON(uintptr_t begin, uintptr_t end) {
   static constexpr size_t kBytesInVector = kWordsInVector * sizeof(uintptr_t);
   PA_SCAN_DCHECK(!(begin % kAlignmentRequirement));
   const uint64x2_t vbase = vdupq_n_u64(derived().CageBase());
-  const uint64x2_t cage_mask = vdupq_n_u64(derived().CageMask());
+  // If the read value is a pointer into the PA region, it's likely
+  // MTE-tagged. Piggyback on |cage_mask| to untag, for efficiency.
+  const uint64x2_t cage_mask =
+      vdupq_n_u64(derived().CageMask() & kPtrUntagMask);
 
   for (; begin <= (end - kBytesInVector); begin += kBytesInVector) {
     // Keep it MTE-untagged. See DisableMTEScope for details.
@@ -224,11 +236,4 @@ void ScanLoop<Derived>::RunNEON(uintptr_t begin, uintptr_t end) {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove this when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::ScanLoop;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_SCAN_LOOP_H_

src/base/allocator/partition_allocator/starscan/snapshot.h

@@ -91,11 +91,4 @@ StarScanSnapshot::UnprotectingView::UnprotectingView(StarScanSnapshot& snapshot)
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove this when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::StarScanSnapshot;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_SNAPSHOT_H_

src/base/allocator/partition_allocator/starscan/stack/stack.h

@@ -45,14 +45,4 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) Stack final {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove these when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::GetStackPointer;
-using ::partition_alloc::internal::GetStackTop;
-using ::partition_alloc::internal::Stack;
-using ::partition_alloc::internal::StackVisitor;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_STACK_STACK_H_

src/base/allocator/partition_allocator/starscan/starscan_fwd.h

@@ -27,12 +27,4 @@ enum class SimdSupport : uint8_t {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove these when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::Context;
-using ::partition_alloc::internal::SimdSupport;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_STARSCAN_FWD_H_

src/base/allocator/partition_allocator/starscan/stats_collector.h

@@ -245,11 +245,4 @@ inline StatsCollector::MetadataString StatsCollector::ToUMAString(
 }  // namespace internal
 }  // namespace partition_alloc
 
-// TODO(crbug.com/1151236): Remove this when migration is complete.
-namespace base::internal {
-
-using ::partition_alloc::internal::StatsCollector;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_STATS_COLLECTOR_H_

src/base/allocator/partition_allocator/starscan/stats_reporter.h

@@ -5,24 +5,22 @@
 #ifndef BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_STATS_REPORTER_H_
 #define BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_STATS_REPORTER_H_
 
+#include "base/allocator/partition_allocator/partition_alloc_base/threading/platform_thread.h"
 #include "base/allocator/partition_allocator/starscan/stats_collector.h"
 
 namespace partition_alloc {
 
-static_assert(sizeof(uint32_t) >= sizeof(internal::base::PlatformThreadId),
-              "sizeof(tid) must be larger than sizeof(PlatformThreadId)");
-
 // StatsReporter is a wrapper to invoke TRACE_EVENT_BEGIN/END, TRACE_COUNTER1,
 // and UmaHistogramTimes. It is used to just remove trace_log and uma
 // dependencies from partition allocator.
 class StatsReporter {
  public:
   virtual void ReportTraceEvent(internal::StatsCollector::ScannerId id,
-                                uint32_t tid,
+                                internal::base::PlatformThreadId tid,
                                 int64_t start_time_ticks_internal_value,
                                 int64_t end_time_ticks_internal_value) {}
   virtual void ReportTraceEvent(internal::StatsCollector::MutatorId id,
-                                uint32_t tid,
+                                internal::base::PlatformThreadId tid,
                                 int64_t start_time_ticks_internal_value,
                                 int64_t end_time_ticks_internal_value) {}
 

src/base/allocator/partition_allocator/starscan/write_protector.cc

@@ -27,9 +27,8 @@
 
 namespace partition_alloc::internal {
 
-::base::internal::PCScan::ClearType NoWriteProtector::SupportedClearType()
+PCScan::ClearType NoWriteProtector::SupportedClearType() const {
-    const {
+  return PCScan::ClearType::kLazy;
-  return ::base::internal::PCScan::ClearType::kLazy;
 }
 
 #if defined(PA_STARSCAN_UFFD_WRITE_PROTECTOR_SUPPORTED)
@@ -58,7 +57,7 @@ void UserFaultFDThread(int uffd) {
 
     // Enter the safepoint. Concurrent faulted writes will wait until safepoint
     // finishes.
-    ::base::internal::PCScan::JoinScanIfNeeded();
+    PCScan::JoinScanIfNeeded();
   }
 }
 }  // namespace
@@ -121,10 +120,8 @@ void UserFaultFDWriteProtector::UnprotectPages(uintptr_t begin, size_t length) {
     UserFaultFDWPSet(uffd_, begin, length, UserFaultFDWPMode::kUnprotect);
 }
 
-::base::internal::PCScan::ClearType
+PCScan::ClearType UserFaultFDWriteProtector::SupportedClearType() const {
-UserFaultFDWriteProtector::SupportedClearType() const {
+  return IsSupported() ? PCScan::ClearType::kEager : PCScan::ClearType::kLazy;
-  return IsSupported() ? ::base::internal::PCScan::ClearType::kEager
-                       : ::base::internal::PCScan::ClearType::kLazy;
 }
 
 bool UserFaultFDWriteProtector::IsSupported() const {

src/base/allocator/partition_allocator/starscan/write_protector.h

@@ -28,14 +28,14 @@ class WriteProtector : public AllocatedOnPCScanMetadataPartition {
 
   virtual bool IsEnabled() const = 0;
 
-  virtual ::base::internal::PCScan::ClearType SupportedClearType() const = 0;
+  virtual PCScan::ClearType SupportedClearType() const = 0;
 };
 
 class NoWriteProtector final : public WriteProtector {
  public:
   void ProtectPages(uintptr_t, size_t) final {}
   void UnprotectPages(uintptr_t, size_t) final {}
-  ::base::internal::PCScan::ClearType SupportedClearType() const final;
+  PCScan::ClearType SupportedClearType() const final;
   inline bool IsEnabled() const override;
 };
 
@@ -55,7 +55,7 @@ class UserFaultFDWriteProtector final : public WriteProtector {
   void ProtectPages(uintptr_t, size_t) final;
   void UnprotectPages(uintptr_t, size_t) final;
 
-  ::base::internal::PCScan::ClearType SupportedClearType() const final;
+  PCScan::ClearType SupportedClearType() const final;
 
   inline bool IsEnabled() const override;
 
@@ -73,15 +73,4 @@ bool UserFaultFDWriteProtector::IsEnabled() const {
 
 }  // namespace partition_alloc::internal
 
-// TODO(crbug.com/1288247): Remove these when migration is complete.
-namespace base::internal {
-using ::partition_alloc::internal::NoWriteProtector;
-using ::partition_alloc::internal::WriteProtector;
-
-#if defined(PA_STARSCAN_UFFD_WRITE_PROTECTOR_SUPPORTED)
-using ::partition_alloc::internal::UserFaultFDWriteProtector;
-#endif  // defined(PA_STARSCAN_UFFD_WRITE_PROTECTOR_SUPPORTED)
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_STARSCAN_WRITE_PROTECTOR_H_

src/base/allocator/partition_allocator/tagging.h

@@ -39,10 +39,11 @@ namespace internal {
 
 constexpr int kMemTagGranuleSize = 16u;
 #if defined(PA_HAS_MEMORY_TAGGING)
-constexpr uint64_t kMemTagUnmask = 0x00ffffffffffffffuLL;
+constexpr uint64_t kPtrTagMask = 0xff00000000000000uLL;
 #else
-constexpr uint64_t kMemTagUnmask = 0xffffffffffffffffuLL;
+constexpr uint64_t kPtrTagMask = 0;
 #endif  // defined(PA_HAS_MEMORY_TAGGING)
+constexpr uint64_t kPtrUntagMask = ~kPtrTagMask;
 
 #if BUILDFLAG(IS_ANDROID)
 // Changes the memory tagging mode for all threads in the current process.
@@ -86,6 +87,7 @@ extern PA_COMPONENT_EXPORT(PARTITION_ALLOC)
 // (e.g. free). Returns the pointer with the new tag. Ensures that the entire
 // range is set to the same tag.
 // TODO(bartekn): Remove the T* variant.
+// TODO(bartekn): Consider removing the return value.
 template <typename T>
 PA_ALWAYS_INLINE T* TagMemoryRangeIncrement(T* ptr, size_t size) {
 #if defined(PA_HAS_MEMORY_TAGGING)
@@ -94,9 +96,8 @@ PA_ALWAYS_INLINE T* TagMemoryRangeIncrement(T* ptr, size_t size) {
   return ptr;
 #endif
 }
-PA_ALWAYS_INLINE uintptr_t TagMemoryRangeIncrement(uintptr_t ptr, size_t size) {
+PA_ALWAYS_INLINE void* TagMemoryRangeIncrement(uintptr_t ptr, size_t size) {
-  return reinterpret_cast<uintptr_t>(
+  return TagMemoryRangeIncrement(reinterpret_cast<void*>(ptr), size);
-      TagMemoryRangeIncrement(reinterpret_cast<void*>(ptr), size));
 }
 
 // Randomly changes the tag of the ptr memory range. Useful for initial random
@@ -114,46 +115,45 @@ PA_ALWAYS_INLINE T* TagMemoryRangeRandomly(T* ptr,
   return ptr;
 #endif
 }
-PA_ALWAYS_INLINE uintptr_t TagMemoryRangeRandomly(uintptr_t ptr,
+PA_ALWAYS_INLINE void* TagMemoryRangeRandomly(uintptr_t ptr,
                                               size_t size,
                                               uint64_t mask = 0u) {
-  return reinterpret_cast<uintptr_t>(
+  return TagMemoryRangeRandomly(reinterpret_cast<void*>(ptr), size, mask);
-      TagMemoryRangeRandomly(reinterpret_cast<void*>(ptr), size, mask));
 }
 
 // Gets a version of ptr that's safe to dereference.
-// TODO(bartekn): Remove the T* variant.
 template <typename T>
-PA_ALWAYS_INLINE T* RemaskPtr(T* ptr) {
+PA_ALWAYS_INLINE T* TagPtr(T* ptr) {
 #if defined(PA_HAS_MEMORY_TAGGING)
   return reinterpret_cast<T*>(global_remask_void_ptr_fn(ptr));
 #else
   return ptr;
 #endif
 }
-// Gets a version of address that's safe to dereference, if cast to a pointer.
+
-PA_ALWAYS_INLINE uintptr_t RemaskPtr(uintptr_t address) {
+// Gets a version of |address| that's safe to dereference, and casts to a
-  return reinterpret_cast<uintptr_t>(
+// pointer.
-      RemaskPtr(reinterpret_cast<void*>(address)));
+PA_ALWAYS_INLINE void* TagAddr(uintptr_t address) {
+  return TagPtr(reinterpret_cast<void*>(address));
 }
 
-// Strips the tag bits off address.
+// Strips the tag bits off |address|.
-PA_ALWAYS_INLINE uintptr_t UnmaskPtr(uintptr_t address) {
+PA_ALWAYS_INLINE uintptr_t UntagAddr(uintptr_t address) {
 #if defined(PA_HAS_MEMORY_TAGGING)
-  return address & kMemTagUnmask;
+  return address & internal::kPtrUntagMask;
 #else
   return address;
 #endif
 }
-// Strips the tag bits off ptr.
-// TODO(bartekn): Remove the T* variant.
-template <typename T>
-PA_ALWAYS_INLINE T* UnmaskPtr(T* ptr) {
-  return reinterpret_cast<T*>(UnmaskPtr(reinterpret_cast<uintptr_t>(ptr)));
-}
 
 }  // namespace internal
 
+// Strips the tag bits off |ptr|.
+template <typename T>
+PA_ALWAYS_INLINE uintptr_t UntagPtr(T* ptr) {
+  return internal::UntagAddr(reinterpret_cast<uintptr_t>(ptr));
+}
+
 }  // namespace partition_alloc
 
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_TAGGING_H_

src/base/allocator/partition_allocator/thread_cache.cc

@@ -10,6 +10,7 @@
 #include <atomic>
 #include <cstdint>
 
+#include "base/allocator/partition_allocator/partition_alloc-inl.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/component_export.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/cxx17_backports.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/debug/debugging_buildflags.h"
@@ -452,7 +453,8 @@ ThreadCache* ThreadCache::Create(PartitionRoot<internal::ThreadSafe>* root) {
   uintptr_t buffer = root->RawAlloc(bucket, AllocFlags::kZeroFill, raw_size,
                                     internal::PartitionPageSize(), &usable_size,
                                     &already_zeroed);
-  ThreadCache* tcache = new (reinterpret_cast<void*>(buffer)) ThreadCache(root);
+  ThreadCache* tcache =
+      new (internal::SlotStartAddr2Ptr(buffer)) ThreadCache(root);
 
   // This may allocate.
   internal::PartitionTlsSet(internal::g_thread_cache_key, tcache);
@@ -519,12 +521,16 @@ void ThreadCache::Delete(void* tcache_ptr) {
 
   auto* root = tcache->root_;
   tcache->~ThreadCache();
-  root->RawFree(reinterpret_cast<uintptr_t>(tcache_ptr));
+  // TreadCache was allocated using RawAlloc() and SlotStartAddr2Ptr(), so it
+  // shifted by extras, but is MTE-tagged.
+  root->RawFree(internal::SlotStartPtr2Addr(tcache_ptr));
 
 #if BUILDFLAG(IS_WIN)
   // On Windows, allocations do occur during thread/process teardown, make sure
   // they don't resurrect the thread cache.
   //
+  // Don't MTE-tag, as it'd mess with the sentinel value.
+  //
   // TODO(lizeb): Investigate whether this is needed on POSIX as well.
   internal::PartitionTlsSet(internal::g_thread_cache_key,
                             reinterpret_cast<void*>(kTombstone));
@@ -679,7 +685,7 @@ void ThreadCache::FreeAfter(internal::PartitionFreelistEntry* head,
   // acquisitions can be expensive.
   internal::ScopedGuard guard(root_->lock_);
   while (head) {
-    uintptr_t slot_start = reinterpret_cast<uintptr_t>(head);
+    uintptr_t slot_start = internal::SlotStartPtr2Addr(head);
     head = head->GetNextForThreadCache<crash_on_corruption>(slot_size);
     root_->RawFreeLocked(slot_start);
   }

src/base/allocator/partition_allocator/thread_cache.h

@@ -10,6 +10,7 @@
 #include <limits>
 #include <memory>
 
+#include "base/allocator/partition_allocator/partition_alloc-inl.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/compiler_specific.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/component_export.h"
 #include "base/allocator/partition_allocator/partition_alloc_base/debug/debugging_buildflags.h"
@@ -247,16 +248,19 @@ class PA_COMPONENT_EXPORT(PARTITION_ALLOC) ThreadCache {
 #if defined(PA_THREAD_CACHE_FAST_TLS)
     return internal::g_thread_cache;
 #else
+    // This region isn't MTE-tagged.
     return reinterpret_cast<ThreadCache*>(
         internal::PartitionTlsGet(internal::g_thread_cache_key));
 #endif
   }
 
   static bool IsValid(ThreadCache* tcache) {
+    // Do not MTE-untag, as it'd mess up the sentinel value.
     return reinterpret_cast<uintptr_t>(tcache) & kTombstoneMask;
   }
 
   static bool IsTombstone(ThreadCache* tcache) {
+    // Do not MTE-untag, as it'd mess up the sentinel value.
     return reinterpret_cast<uintptr_t>(tcache) == kTombstone;
   }
 
@@ -527,14 +531,14 @@ PA_ALWAYS_INLINE uintptr_t ThreadCache::GetFromCache(size_t bucket_index,
   }
 
   PA_DCHECK(bucket.count != 0);
-  internal::PartitionFreelistEntry* result = bucket.freelist_head;
+  internal::PartitionFreelistEntry* entry = bucket.freelist_head;
   // Passes the bucket size to |GetNext()|, so that in case of freelist
   // corruption, we know the bucket size that lead to the crash, helping to
   // narrow down the search for culprit. |bucket| was touched just now, so this
   // does not introduce another cache miss.
   internal::PartitionFreelistEntry* next =
-      result->GetNextForThreadCache<true>(bucket.slot_size);
+      entry->GetNextForThreadCache<true>(bucket.slot_size);
-  PA_DCHECK(result != next);
+  PA_DCHECK(entry != next);
   bucket.count--;
   PA_DCHECK(bucket.count != 0 || !next);
   bucket.freelist_head = next;
@@ -542,7 +546,7 @@ PA_ALWAYS_INLINE uintptr_t ThreadCache::GetFromCache(size_t bucket_index,
 
   PA_DCHECK(cached_memory_ >= bucket.slot_size);
   cached_memory_ -= bucket.slot_size;
-  return reinterpret_cast<uintptr_t>(result);
+  return internal::SlotStartPtr2Addr(entry);
 }
 
 PA_ALWAYS_INLINE void ThreadCache::PutInBucket(Bucket& bucket,
@@ -565,19 +569,23 @@ PA_ALWAYS_INLINE void ThreadCache::PutInBucket(Bucket& bucket,
   static_assert(internal::kAlignment == 16, "");
 
 #if PA_HAS_BUILTIN(__builtin_assume_aligned)
-  uintptr_t address = reinterpret_cast<uintptr_t>(__builtin_assume_aligned(
+  // Cast back to uintptr_t, because we need it for pointer arithmetic. Make
-      reinterpret_cast<void*>(slot_start), internal::kAlignment));
+  // sure it gets MTE-tagged, as we cast it later to a pointer and dereference.
+  uintptr_t address_tagged =
+      reinterpret_cast<uintptr_t>(__builtin_assume_aligned(
+          internal::SlotStartAddr2Ptr(slot_start), internal::kAlignment));
 #else
-  uintptr_t address = slot_start;
+  uintptr_t address_tagged =
+      reinterpret_cast<uintptr_t>(internal::SlotStartAddr2Ptr(slot_start));
 #endif
 
   // The pointer is always 16 bytes aligned, so its start address is always == 0
-  // % 16. Its distance to the next cacheline is 64 - ((address & 63) / 16) *
+  // % 16. Its distance to the next cacheline is `64 - ((address_tagged & 63) /
-  // 16.
+  // 16) * 16`.
   static_assert(
       internal::kPartitionCachelineSize == 64,
       "The computation below assumes that cache lines are 64 bytes long.");
-  int distance_to_next_cacheline_in_16_bytes = 4 - ((address >> 4) & 3);
+  int distance_to_next_cacheline_in_16_bytes = 4 - ((address_tagged >> 4) & 3);
   int slot_size_remaining_in_16_bytes =
 #if BUILDFLAG(PUT_REF_COUNT_IN_PREVIOUS_SLOT)
       // When BRP is on in the "previous slot" mode, this slot may have a BRP
@@ -591,10 +599,10 @@ PA_ALWAYS_INLINE void ThreadCache::PutInBucket(Bucket& bucket,
   slot_size_remaining_in_16_bytes = std::min(
       slot_size_remaining_in_16_bytes, distance_to_next_cacheline_in_16_bytes);
 
-  static const uint32_t poison_16_bytes[4] = {0xdeadbeef, 0xdeadbeef,
+  static const uint32_t poison_16_bytes[4] = {0xbadbad00, 0xbadbad00,
-                                              0xdeadbeef, 0xdeadbeef};
+                                              0xbadbad00, 0xbadbad00};
-  uint32_t* address_aligned = reinterpret_cast<uint32_t*>(address);
+  // Already MTE-tagged above, so safe to dereference.
-
+  uint32_t* address_aligned = reinterpret_cast<uint32_t*>(address_tagged);
   for (int i = 0; i < slot_size_remaining_in_16_bytes; i++) {
     // Clang will expand the memcpy to a 16-byte write (movups on x86).
     memcpy(address_aligned, poison_16_bytes, sizeof(poison_16_bytes));
@@ -611,13 +619,4 @@ PA_ALWAYS_INLINE void ThreadCache::PutInBucket(Bucket& bucket,
 
 }  // namespace partition_alloc
 
-namespace base::internal {
-
-// TODO(https://crbug.com/1288247): Remove these 'using' declarations once
-// the migration to the new namespaces gets done.
-using ::partition_alloc::ThreadCache;
-using ::partition_alloc::ThreadCacheRegistry;
-
-}  // namespace base::internal
-
 #endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_THREAD_CACHE_H_

src/base/allocator/winheap_stubs_win.cc

@@ -17,6 +17,7 @@
 
 #include "base/bits.h"
 #include "base/check_op.h"
+#include "base/numerics/safe_conversions.h"
 
 namespace base {
 namespace allocator {
@@ -122,7 +123,7 @@ void* AlignAllocation(void* ptr, size_t alignment) {
   // Write the prefix.
   AlignedPrefix* prefix = reinterpret_cast<AlignedPrefix*>(address) - 1;
   prefix->original_allocation_offset =
-      address - reinterpret_cast<uintptr_t>(ptr);
+      checked_cast<unsigned int>(address - reinterpret_cast<uintptr_t>(ptr));
 #if DCHECK_IS_ON()
   prefix->magic = AlignedPrefix::kMagic;
 #endif  // DCHECK_IS_ON()

src/base/android/apk_assets.cc

@@ -29,7 +29,8 @@ int OpenApkAsset(const std::string& file_path,
   CHECK_EQ(3U, results.size());
   int fd = static_cast<int>(results[0]);
   region->offset = results[1];
-  region->size = results[2];
+  // Not a checked_cast because open() may return -1.
+  region->size = static_cast<size_t>(results[2]);
   return fd;
 }
 

src/base/android/build_info.cc

@@ -21,11 +21,11 @@ namespace android {
 namespace {
 
 // We are leaking these strings.
-const char* StrDupParam(const std::vector<std::string>& params, int index) {
+const char* StrDupParam(const std::vector<std::string>& params, size_t index) {
   return strdup(params[index].c_str());
 }
 
-int GetIntParam(const std::vector<std::string>& params, int index) {
+int GetIntParam(const std::vector<std::string>& params, size_t index) {
   int ret = 0;
   bool success = StringToInt(params[index], &ret);
   DCHECK(success);

src/base/android/child_process_service.cc

@@ -27,7 +27,7 @@ void JNI_ChildProcessService_RegisterFileDescriptors(
     const JavaParamRef<jlongArray>& j_sizes) {
   std::vector<absl::optional<std::string>> keys;
   JavaObjectArrayReader<jstring> keys_array(j_keys);
-  keys.reserve(keys_array.size());
+  keys.reserve(checked_cast<size_t>(keys_array.size()));
   for (auto str : keys_array) {
     absl::optional<std::string> key;
     if (str) {
@@ -54,7 +54,7 @@ void JNI_ChildProcessService_RegisterFileDescriptors(
     base::MemoryMappedFile::Region region = {offsets.at(i),
                                              static_cast<size_t>(sizes.at(i))};
     const absl::optional<std::string>& key = keys.at(i);
-    int id = ids.at(i);
+    const auto id = static_cast<GlobalDescriptors::Key>(ids.at(i));
     int fd = fds.at(i);
     if (key) {
       base::FileDescriptorStore::GetInstance().Set(*key, base::ScopedFD(fd),

src/base/android/cpu_features.cc

@@ -15,7 +15,7 @@ jint JNI_CpuFeatures_GetCoreCount(JNIEnv*) {
 }
 
 jlong JNI_CpuFeatures_GetCpuFeatures(JNIEnv*) {
-  return android_getCpuFeatures();
+  return static_cast<jlong>(android_getCpuFeatures());
 }
 
 }  // namespace android

src/base/android/early_trace_event_binding.cc

@@ -106,7 +106,8 @@ static void JNI_EarlyTraceEvent_RecordEarlyAsyncBeginEvent(
   std::string name = ConvertJavaStringToUTF8(env, jname);
 
   TRACE_EVENT_NESTABLE_ASYNC_BEGIN_WITH_TIMESTAMP_AND_FLAGS0(
-      internal::kJavaTraceCategory, name.c_str(), TRACE_ID_LOCAL(id),
+      internal::kJavaTraceCategory, name.c_str(),
+      TRACE_ID_LOCAL(static_cast<uint64_t>(id)),
       TimeTicks::FromJavaNanoTime(time_ns),
       TRACE_EVENT_FLAG_JAVA_STRING_LITERALS | TRACE_EVENT_FLAG_COPY);
 }
@@ -119,7 +120,8 @@ static void JNI_EarlyTraceEvent_RecordEarlyAsyncEndEvent(
   std::string name = ConvertJavaStringToUTF8(env, jname);
 
   TRACE_EVENT_NESTABLE_ASYNC_END_WITH_TIMESTAMP_AND_FLAGS0(
-      internal::kJavaTraceCategory, name.c_str(), TRACE_ID_LOCAL(id),
+      internal::kJavaTraceCategory, name.c_str(),
+      TRACE_ID_LOCAL(static_cast<uint64_t>(id)),
       TimeTicks::FromJavaNanoTime(time_ns),
       TRACE_EVENT_FLAG_JAVA_STRING_LITERALS | TRACE_EVENT_FLAG_COPY);
 }

src/base/android/jank_metric_uma_recorder.cc

@@ -23,7 +23,9 @@ namespace {
 
 void AddFrameToTrace(int64_t timestamp_ns, int64_t durations_ns) {
 #if BUILDFLAG(ENABLE_BASE_TRACING)
-  auto t = perfetto::Track(timestamp_ns);
+  if (timestamp_ns < 0)
+    return;
+  auto t = perfetto::Track(static_cast<uint64_t>(timestamp_ns));
   TRACE_EVENT_BEGIN(
       "ui", "AndroidFrameVsync", t, [&](perfetto::EventContext ctx) {
         ctx.event()->set_timestamp_absolute_us(timestamp_ns / 1000);
@@ -75,7 +77,7 @@ void RecordJankMetrics(
   std::string missed_frames_histogram_name =
       base::StrCat({"Android.Jank.MissedFrames.", scenario_name});
 
-  for (unsigned i = 0; i < timestamps_ns.size(); ++i) {
+  for (size_t i = 0; i < timestamps_ns.size(); ++i) {
     AddFrameToTrace(timestamps_ns[i], durations_ns[i]);
   }
 

src/base/android/java_exception_reporter.cc

@@ -26,7 +26,8 @@ void (*g_java_exception_callback)(const char*);
 using JavaExceptionFilter =
     base::RepeatingCallback<bool(const JavaRef<jthrowable>&)>;
 
-LazyInstance<JavaExceptionFilter>::Leaky g_java_exception_filter;
+LazyInstance<JavaExceptionFilter>::Leaky g_java_exception_filter =
+    LAZY_INSTANCE_INITIALIZER;
 
 }  // namespace
 

src/base/android/java_handler_thread.cc

@@ -26,13 +26,13 @@ namespace base {
 namespace android {
 
 JavaHandlerThread::JavaHandlerThread(const char* name,
-                                     base::ThreadPriority priority)
+                                     base::ThreadType thread_type)
     : JavaHandlerThread(
           name,
           Java_JavaHandlerThread_create(
               AttachCurrentThread(),
               ConvertUTF8ToJavaString(AttachCurrentThread(), name),
-              base::internal::ThreadPriorityToNiceValue(priority))) {}
+              base::internal::ThreadTypeToNiceValue(thread_type))) {}
 
 JavaHandlerThread::JavaHandlerThread(
     const char* name,

src/base/android/java_handler_thread.h

@@ -33,7 +33,7 @@ class BASE_EXPORT JavaHandlerThread {
   // Create new thread.
   explicit JavaHandlerThread(
       const char* name,
-      base::ThreadPriority priority = base::ThreadPriority::NORMAL);
+      base::ThreadType thread_type = base::ThreadType::kDefault);
   // Wrap and connect to an existing JavaHandlerThread.
   // |obj| is an instance of JavaHandlerThread.
   explicit JavaHandlerThread(

src/base/android/java_runtime.cc

@@ -5,16 +5,20 @@
 #include "base/android/java_runtime.h"
 
 #include "base/android_runtime_jni_headers/Runtime_jni.h"
+#include "base/numerics/safe_conversions.h"
 
 namespace base {
 namespace android {
 
-void JavaRuntime::GetMemoryUsage(long* total_memory, long* free_memory) {
+void JavaRuntime::GetMemoryUsage(uint64_t* total_memory,
+                                 uint64_t* free_memory) {
   JNIEnv* env = base::android::AttachCurrentThread();
   base::android::ScopedJavaLocalRef<jobject> runtime =
       JNI_Runtime::Java_Runtime_getRuntime(env);
-  *total_memory = JNI_Runtime::Java_Runtime_totalMemory(env, runtime);
+  *total_memory = checked_cast<uint64_t>(
-  *free_memory = JNI_Runtime::Java_Runtime_freeMemory(env, runtime);
+      JNI_Runtime::Java_Runtime_totalMemory(env, runtime));
+  *free_memory = checked_cast<uint64_t>(
+      JNI_Runtime::Java_Runtime_freeMemory(env, runtime));
 }
 
 }  // namespace android

src/base/android/java_runtime.h

@@ -16,7 +16,7 @@ class BASE_EXPORT JavaRuntime {
  public:
   // Fills the total memory used and memory allocated for objects by the java
   // heap in the current process. Returns true on success.
-  static void GetMemoryUsage(long* total_memory, long* free_memory);
+  static void GetMemoryUsage(uint64_t* total_memory, uint64_t* free_memory);
 };
 
 }  // namespace android

src/base/android/jni_array.cc

@@ -9,6 +9,7 @@
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/check_op.h"
+#include "base/numerics/safe_conversions.h"
 
 namespace base {
 namespace android {
@@ -30,11 +31,12 @@ size_t SafeGetArrayLength(JNIEnv* env, const JavaRef<JavaArrayType>& jarray) {
 ScopedJavaLocalRef<jbyteArray> ToJavaByteArray(JNIEnv* env,
                                                const uint8_t* bytes,
                                                size_t len) {
-  jbyteArray byte_array = env->NewByteArray(len);
+  const jsize len_jsize = checked_cast<jsize>(len);
+  jbyteArray byte_array = env->NewByteArray(len_jsize);
   CheckException(env);
   DCHECK(byte_array);
 
-  env->SetByteArrayRegion(byte_array, 0, len,
+  env->SetByteArrayRegion(byte_array, 0, len_jsize,
                           reinterpret_cast<const jbyte*>(bytes));
   CheckException(env);
 
@@ -56,11 +58,12 @@ ScopedJavaLocalRef<jbyteArray> ToJavaByteArray(JNIEnv* env,
 ScopedJavaLocalRef<jbooleanArray> ToJavaBooleanArray(JNIEnv* env,
                                                      const bool* bools,
                                                      size_t len) {
-  jbooleanArray boolean_array = env->NewBooleanArray(len);
+  const jsize len_jsize = checked_cast<jsize>(len);
+  jbooleanArray boolean_array = env->NewBooleanArray(len_jsize);
   CheckException(env);
   DCHECK(boolean_array);
 
-  env->SetBooleanArrayRegion(boolean_array, 0, len,
+  env->SetBooleanArrayRegion(boolean_array, 0, len_jsize,
                              reinterpret_cast<const jboolean*>(bools));
   CheckException(env);
 
@@ -70,11 +73,12 @@ ScopedJavaLocalRef<jbooleanArray> ToJavaBooleanArray(JNIEnv* env,
 ScopedJavaLocalRef<jintArray> ToJavaIntArray(JNIEnv* env,
                                              const int* ints,
                                              size_t len) {
-  jintArray int_array = env->NewIntArray(len);
+  const jsize len_jsize = checked_cast<jsize>(len);
+  jintArray int_array = env->NewIntArray(len_jsize);
   CheckException(env);
   DCHECK(int_array);
 
-  env->SetIntArrayRegion(int_array, 0, len,
+  env->SetIntArrayRegion(int_array, 0, len_jsize,
                          reinterpret_cast<const jint*>(ints));
   CheckException(env);
 
@@ -89,11 +93,12 @@ ScopedJavaLocalRef<jintArray> ToJavaIntArray(JNIEnv* env,
 ScopedJavaLocalRef<jlongArray> ToJavaLongArray(JNIEnv* env,
                                                const int64_t* longs,
                                                size_t len) {
-  jlongArray long_array = env->NewLongArray(len);
+  const jsize len_jsize = checked_cast<jsize>(len);
+  jlongArray long_array = env->NewLongArray(len_jsize);
   CheckException(env);
   DCHECK(long_array);
 
-  env->SetLongArrayRegion(long_array, 0, len,
+  env->SetLongArrayRegion(long_array, 0, len_jsize,
                           reinterpret_cast<const jlong*>(longs));
   CheckException(env);
 
@@ -110,11 +115,12 @@ BASE_EXPORT ScopedJavaLocalRef<jlongArray> ToJavaLongArray(
 // Returns a new Java float array converted from the given C++ float array.
 BASE_EXPORT ScopedJavaLocalRef<jfloatArray>
 ToJavaFloatArray(JNIEnv* env, const float* floats, size_t len) {
-  jfloatArray float_array = env->NewFloatArray(len);
+  const jsize len_jsize = checked_cast<jsize>(len);
+  jfloatArray float_array = env->NewFloatArray(len_jsize);
   CheckException(env);
   DCHECK(float_array);
 
-  env->SetFloatArrayRegion(float_array, 0, len,
+  env->SetFloatArrayRegion(float_array, 0, len_jsize,
                            reinterpret_cast<const jfloat*>(floats));
   CheckException(env);
 
@@ -129,11 +135,12 @@ BASE_EXPORT ScopedJavaLocalRef<jfloatArray> ToJavaFloatArray(
 
 BASE_EXPORT ScopedJavaLocalRef<jdoubleArray>
 ToJavaDoubleArray(JNIEnv* env, const double* doubles, size_t len) {
-  jdoubleArray double_array = env->NewDoubleArray(len);
+  const jsize len_jsize = checked_cast<jsize>(len);
+  jdoubleArray double_array = env->NewDoubleArray(len_jsize);
   CheckException(env);
   DCHECK(double_array);
 
-  env->SetDoubleArrayRegion(double_array, 0, len,
+  env->SetDoubleArrayRegion(double_array, 0, len_jsize,
                             reinterpret_cast<const jdouble*>(doubles));
   CheckException(env);
 
@@ -150,11 +157,12 @@ BASE_EXPORT ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfObjects(
     JNIEnv* env,
     ScopedJavaLocalRef<jclass> clazz,
     base::span<const ScopedJavaLocalRef<jobject>> v) {
-  jobjectArray joa = env->NewObjectArray(v.size(), clazz.obj(), nullptr);
+  jobjectArray joa =
+      env->NewObjectArray(checked_cast<jsize>(v.size()), clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
-    env->SetObjectArrayElement(joa, i, v[i].obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), v[i].obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -170,12 +178,12 @@ BASE_EXPORT ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfObjects(
     base::span<const ScopedJavaGlobalRef<jobject>> v) {
   ScopedJavaLocalRef<jclass> object_array_clazz =
       GetClass(env, "java/lang/Object");
-  jobjectArray joa =
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(v.size()),
-      env->NewObjectArray(v.size(), object_array_clazz.obj(), nullptr);
+                                         object_array_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
-    env->SetObjectArrayElement(joa, i, v[i].obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), v[i].obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -184,11 +192,12 @@ BASE_EXPORT ScopedJavaLocalRef<jobjectArray> ToTypedJavaArrayOfObjects(
     JNIEnv* env,
     base::span<const ScopedJavaLocalRef<jobject>> v,
     ScopedJavaLocalRef<jclass> type) {
-  jobjectArray joa = env->NewObjectArray(v.size(), type.obj(), nullptr);
+  jobjectArray joa =
+      env->NewObjectArray(checked_cast<jsize>(v.size()), type.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
-    env->SetObjectArrayElement(joa, i, v[i].obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), v[i].obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -197,11 +206,12 @@ BASE_EXPORT ScopedJavaLocalRef<jobjectArray> ToTypedJavaArrayOfObjects(
     JNIEnv* env,
     base::span<const ScopedJavaGlobalRef<jobject>> v,
     ScopedJavaLocalRef<jclass> type) {
-  jobjectArray joa = env->NewObjectArray(v.size(), type.obj(), nullptr);
+  jobjectArray joa =
+      env->NewObjectArray(checked_cast<jsize>(v.size()), type.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
-    env->SetObjectArrayElement(joa, i, v[i].obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), v[i].obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -210,14 +220,14 @@ ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfByteArray(
     JNIEnv* env,
     base::span<const std::string> v) {
   ScopedJavaLocalRef<jclass> byte_array_clazz = GetClass(env, "[B");
-  jobjectArray joa =
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(v.size()),
-      env->NewObjectArray(v.size(), byte_array_clazz.obj(), nullptr);
+                                         byte_array_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
     ScopedJavaLocalRef<jbyteArray> byte_array = ToJavaByteArray(
         env, reinterpret_cast<const uint8_t*>(v[i].data()), v[i].length());
-    env->SetObjectArrayElement(joa, i, byte_array.obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), byte_array.obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -226,14 +236,14 @@ ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfByteArray(
     JNIEnv* env,
     base::span<const std::vector<uint8_t>> v) {
   ScopedJavaLocalRef<jclass> byte_array_clazz = GetClass(env, "[B");
-  jobjectArray joa =
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(v.size()),
-      env->NewObjectArray(v.size(), byte_array_clazz.obj(), nullptr);
+                                         byte_array_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
     ScopedJavaLocalRef<jbyteArray> byte_array =
         ToJavaByteArray(env, v[i].data(), v[i].size());
-    env->SetObjectArrayElement(joa, i, byte_array.obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), byte_array.obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -242,12 +252,13 @@ ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfStrings(
     JNIEnv* env,
     base::span<const std::string> v) {
   ScopedJavaLocalRef<jclass> string_clazz = GetClass(env, "java/lang/String");
-  jobjectArray joa = env->NewObjectArray(v.size(), string_clazz.obj(), nullptr);
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(v.size()),
+                                         string_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
     ScopedJavaLocalRef<jstring> item = ConvertUTF8ToJavaString(env, v[i]);
-    env->SetObjectArrayElement(joa, i, item.obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), item.obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -258,14 +269,14 @@ ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfStringArray(
   ScopedJavaLocalRef<jclass> string_array_clazz =
       GetClass(env, "[Ljava/lang/String;");
 
-  jobjectArray joa =
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(vec_outer.size()),
-      env->NewObjectArray(vec_outer.size(), string_array_clazz.obj(), nullptr);
+                                         string_array_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < vec_outer.size(); ++i) {
     ScopedJavaLocalRef<jobjectArray> inner =
         ToJavaArrayOfStrings(env, vec_outer[i]);
-    env->SetObjectArrayElement(joa, i, inner.obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), inner.obj());
   }
 
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
@@ -277,14 +288,14 @@ ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfStringArray(
   ScopedJavaLocalRef<jclass> string_array_clazz =
       GetClass(env, "[Ljava/lang/String;");
 
-  jobjectArray joa =
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(vec_outer.size()),
-      env->NewObjectArray(vec_outer.size(), string_array_clazz.obj(), nullptr);
+                                         string_array_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < vec_outer.size(); ++i) {
     ScopedJavaLocalRef<jobjectArray> inner =
         ToJavaArrayOfStrings(env, vec_outer[i]);
-    env->SetObjectArrayElement(joa, i, inner.obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), inner.obj());
   }
 
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
@@ -294,12 +305,13 @@ ScopedJavaLocalRef<jobjectArray> ToJavaArrayOfStrings(
     JNIEnv* env,
     base::span<const std::u16string> v) {
   ScopedJavaLocalRef<jclass> string_clazz = GetClass(env, "java/lang/String");
-  jobjectArray joa = env->NewObjectArray(v.size(), string_clazz.obj(), nullptr);
+  jobjectArray joa = env->NewObjectArray(checked_cast<jsize>(v.size()),
+                                         string_clazz.obj(), nullptr);
   CheckException(env);
 
   for (size_t i = 0; i < v.size(); ++i) {
     ScopedJavaLocalRef<jstring> item = ConvertUTF16ToJavaString(env, v[i]);
-    env->SetObjectArrayElement(joa, i, item.obj());
+    env->SetObjectArrayElement(joa, static_cast<jsize>(i), item.obj());
   }
   return ScopedJavaLocalRef<jobjectArray>(env, joa);
 }
@@ -315,7 +327,8 @@ void AppendJavaStringArrayToStringVector(JNIEnv* env,
   out->resize(back + len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jstring> str(
-        env, static_cast<jstring>(env->GetObjectArrayElement(array.obj(), i)));
+        env, static_cast<jstring>(env->GetObjectArrayElement(
+                 array.obj(), static_cast<jsize>(i))));
     ConvertJavaStringToUTF16(env, str.obj(), out->data() + back + i);
   }
 }
@@ -331,7 +344,8 @@ void AppendJavaStringArrayToStringVector(JNIEnv* env,
   out->resize(back + len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jstring> str(
-        env, static_cast<jstring>(env->GetObjectArrayElement(array.obj(), i)));
+        env, static_cast<jstring>(env->GetObjectArrayElement(
+                 array.obj(), static_cast<jsize>(i))));
     ConvertJavaStringToUTF8(env, str.obj(), out->data() + back + i);
   }
 }
@@ -347,7 +361,7 @@ void AppendJavaByteArrayToByteVector(JNIEnv* env,
     return;
   size_t back = out->size();
   out->resize(back + len);
-  env->GetByteArrayRegion(byte_array.obj(), 0, len,
+  env->GetByteArrayRegion(byte_array.obj(), 0, static_cast<jsize>(len),
                           reinterpret_cast<int8_t*>(out->data() + back));
 }
 
@@ -397,7 +411,8 @@ void JavaIntArrayToIntVector(JNIEnv* env,
   out->resize(len);
   if (!len)
     return;
-  env->GetIntArrayRegion(int_array.obj(), 0, len, out->data());
+  env->GetIntArrayRegion(int_array.obj(), 0, static_cast<jsize>(len),
+                         out->data());
 }
 
 void JavaLongArrayToInt64Vector(JNIEnv* env,
@@ -418,7 +433,8 @@ void JavaLongArrayToLongVector(JNIEnv* env,
   out->resize(len);
   if (!len)
     return;
-  env->GetLongArrayRegion(long_array.obj(), 0, len, out->data());
+  env->GetLongArrayRegion(long_array.obj(), 0, static_cast<jsize>(len),
+                          out->data());
 }
 
 void JavaFloatArrayToFloatVector(JNIEnv* env,
@@ -429,7 +445,8 @@ void JavaFloatArrayToFloatVector(JNIEnv* env,
   out->resize(len);
   if (!len)
     return;
-  env->GetFloatArrayRegion(float_array.obj(), 0, len, out->data());
+  env->GetFloatArrayRegion(float_array.obj(), 0, static_cast<jsize>(len),
+                           out->data());
 }
 
 void JavaDoubleArrayToDoubleVector(JNIEnv* env,
@@ -440,7 +457,8 @@ void JavaDoubleArrayToDoubleVector(JNIEnv* env,
   out->resize(len);
   if (!len)
     return;
-  env->GetDoubleArrayRegion(double_array.obj(), 0, len, out->data());
+  env->GetDoubleArrayRegion(double_array.obj(), 0, static_cast<jsize>(len),
+                            out->data());
 }
 
 void JavaArrayOfByteArrayToStringVector(JNIEnv* env,
@@ -451,9 +469,9 @@ void JavaArrayOfByteArrayToStringVector(JNIEnv* env,
   out->resize(len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jbyteArray> bytes_array(
-        env,
+        env, static_cast<jbyteArray>(env->GetObjectArrayElement(
-        static_cast<jbyteArray>(env->GetObjectArrayElement(array.obj(), i)));
+                 array.obj(), static_cast<jsize>(i))));
-    jsize bytes_len = env->GetArrayLength(bytes_array.obj());
+    size_t bytes_len = SafeGetArrayLength(env, bytes_array);
     jbyte* bytes = env->GetByteArrayElements(bytes_array.obj(), nullptr);
     (*out)[i].assign(reinterpret_cast<const char*>(bytes), bytes_len);
     env->ReleaseByteArrayElements(bytes_array.obj(), bytes, JNI_ABORT);
@@ -468,8 +486,8 @@ void JavaArrayOfByteArrayToBytesVector(JNIEnv* env,
   out->resize(len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jbyteArray> bytes_array(
-        env,
+        env, static_cast<jbyteArray>(env->GetObjectArrayElement(
-        static_cast<jbyteArray>(env->GetObjectArrayElement(array.obj(), i)));
+                 array.obj(), static_cast<jsize>(i))));
     JavaByteArrayToByteVector(env, bytes_array, &(*out)[i]);
   }
 }
@@ -483,8 +501,8 @@ void Java2dStringArrayTo2dStringVector(
   out->resize(len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jobjectArray> strings_array(
-        env,
+        env, static_cast<jobjectArray>(env->GetObjectArrayElement(
-        static_cast<jobjectArray>(env->GetObjectArrayElement(array.obj(), i)));
+                 array.obj(), static_cast<jsize>(i))));
 
     out->at(i).clear();
     AppendJavaStringArrayToStringVector(env, strings_array, &out->at(i));
@@ -500,8 +518,8 @@ void Java2dStringArrayTo2dStringVector(
   out->resize(len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jobjectArray> strings_array(
-        env,
+        env, static_cast<jobjectArray>(env->GetObjectArrayElement(
-        static_cast<jobjectArray>(env->GetObjectArrayElement(array.obj(), i)));
+                 array.obj(), static_cast<jsize>(i))));
 
     out->at(i).clear();
     AppendJavaStringArrayToStringVector(env, strings_array, &out->at(i));
@@ -516,8 +534,8 @@ void JavaArrayOfIntArrayToIntVector(JNIEnv* env,
   out->resize(len);
   for (size_t i = 0; i < len; ++i) {
     ScopedJavaLocalRef<jintArray> int_array(
-        env,
+        env, static_cast<jintArray>(env->GetObjectArrayElement(
-        static_cast<jintArray>(env->GetObjectArrayElement(array.obj(), i)));
+                 array.obj(), static_cast<jsize>(i))));
     JavaIntArrayToIntVector(env, int_array, &out->at(i));
   }
 }

src/base/android/jni_generator/BUILD.gn

@@ -99,6 +99,5 @@ java_annotation_processor("jni_processor") {
     "//third_party/android_deps:com_google_auto_service_auto_service_annotations_java",
     "//third_party/android_deps:com_google_guava_guava_java",
     "//third_party/android_deps:com_squareup_javapoet_java",
-    "//third_party/android_deps:javax_annotation_jsr250_api_java",
   ]
 }

src/base/android/jni_generator/PRESUBMIT.py

@@ -20,15 +20,17 @@ def CommonChecks(input_api, output_api):
       'PYTHONDONTWRITEBYTECODE': '1',
   })
 
-  return input_api.canned_checks.RunUnitTests(
+  return input_api.RunTests(
+      input_api.canned_checks.GetUnitTests(
           input_api,
           output_api,
+          run_on_python2=False,
           unit_tests=[
               input_api.os_path.join(base_android_jni_generator_dir,
                                      'jni_generator_tests.py')
           ],
           env=env,
-  )
+      ))
 
 
 def CheckChangeOnUpload(input_api, output_api):

src/base/android/jni_generator/jni_generator_tests.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
@@ -11,8 +11,6 @@ code generator and ensures the output matches a golden
 file.
 """
 
-from __future__ import print_function
-
 import collections
 import difflib
 import inspect

src/base/android/jni_string.cc

@@ -6,6 +6,7 @@
 
 #include "base/android/jni_android.h"
 #include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 
 namespace {
@@ -13,8 +14,8 @@ namespace {
 // Internal version that does not use a scoped local pointer.
 jstring ConvertUTF16ToJavaStringImpl(JNIEnv* env,
                                      const base::StringPiece16& str) {
-  jstring result =
+  jstring result = env->NewString(reinterpret_cast<const jchar*>(str.data()),
-      env->NewString(reinterpret_cast<const jchar*>(str.data()), str.length());
+                                  base::checked_cast<jsize>(str.length()));
   base::android::CheckException(env);
   return result;
 }
@@ -32,7 +33,7 @@ void ConvertJavaStringToUTF8(JNIEnv* env, jstring str, std::string* result) {
     return;
   }
   const jsize length = env->GetStringLength(str);
-  if (!length) {
+  if (length <= 0) {
     result->clear();
     CheckException(env);
     return;
@@ -42,7 +43,8 @@ void ConvertJavaStringToUTF8(JNIEnv* env, jstring str, std::string* result) {
   // function that yields plain (non Java-modified) UTF8.
   const jchar* chars = env->GetStringChars(str, NULL);
   DCHECK(chars);
-  UTF16ToUTF8(reinterpret_cast<const char16_t*>(chars), length, result);
+  UTF16ToUTF8(reinterpret_cast<const char16_t*>(chars),
+              static_cast<size_t>(length), result);
   env->ReleaseStringChars(str, chars);
   CheckException(env);
 }
@@ -84,7 +86,7 @@ void ConvertJavaStringToUTF16(JNIEnv* env,
     return;
   }
   const jsize length = env->GetStringLength(str);
-  if (!length) {
+  if (length <= 0) {
     result->clear();
     CheckException(env);
     return;
@@ -93,7 +95,8 @@ void ConvertJavaStringToUTF16(JNIEnv* env,
   DCHECK(chars);
   // GetStringChars isn't required to NULL-terminate the strings
   // it returns, so the length must be explicitly checked.
-  result->assign(reinterpret_cast<const char16_t*>(chars), length);
+  result->assign(reinterpret_cast<const char16_t*>(chars),
+                 static_cast<size_t>(length));
   env->ReleaseStringChars(str, chars);
   CheckException(env);
 }

src/base/android/junit/PRESUBMIT.py

@@ -1,30 +0,0 @@
-# Copyright 2020 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-USE_PYTHON3 = True
-
-
-def CheckChangeOnUpload(input_api, output_api):
-    results = []
-
-    # Dictionary of base/android files with corresponding Robolectric shadows.
-    # If new functions are added to the original file, it is very likely that
-    # function with the same signature should be added to the shadow.
-    impl_to_shadow_paths = {
-        'base/android/java/src/org/'
-        'chromium/base/metrics/RecordHistogram.java':
-            'base/android/junit/src/org/'
-            'chromium/base/metrics/test/ShadowRecordHistogram.java'
-    }
-
-    for impl_path, shadow_path in impl_to_shadow_paths.items():
-        if impl_path in input_api.change.LocalPaths():
-            if shadow_path not in input_api.change.LocalPaths():
-                results.append(
-                    output_api.PresubmitPromptWarning(
-                        'You modified the runtime class:\n  {}\n'
-                        'without changing the corresponding shadow test class'
-                        ':\n  {}\n').format(impl_path, shadow_path))
-
-    return results