Fix recommitted pages not being zeroed when madvise is not available.

.github/workflows/build.yml

@@ -404,7 +404,7 @@ jobs:
           - arch: aarch64_cortex-a53-static
             openwrt: 'target=sunxi subtarget=cortexa53'
             target_cpu: arm64
-            extra: 'arm_cpu="cortex-a53" build_static=true'
+            extra: 'arm_cpu="cortex-a53" build_static=true no_madvise_syscall=true'
           - arch: aarch64_cortex-a72
             openwrt: 'target=mvebu subtarget=cortexa72'
             target_cpu: arm64
@@ -443,7 +443,7 @@ jobs:
           - arch: arm_cortex-a7_neon-vfpv4-static
             openwrt: 'target=sunxi subtarget=cortexa7'
             target_cpu: arm
-            extra: 'arm_version=0 arm_cpu="cortex-a7" arm_fpu="neon-vfpv4" arm_float_abi="hard" arm_use_neon=true build_static=true'
+            extra: 'arm_version=0 arm_cpu="cortex-a7" arm_fpu="neon-vfpv4" arm_float_abi="hard" arm_use_neon=true build_static=true no_madvise_syscall=true'
           - arch: arm_cortex-a8_vfpv3
             openwrt: 'target=sunxi subtarget=cortexa8'
             target_cpu: arm
@@ -455,7 +455,7 @@ jobs:
           - arch: arm_cortex-a9-static
             openwrt: 'target=bcm53xx subtarget=generic'
             target_cpu: arm
-            extra: 'arm_version=0 arm_cpu="cortex-a9" arm_float_abi="soft" arm_use_neon=false build_static=true'
+            extra: 'arm_version=0 arm_cpu="cortex-a9" arm_float_abi="soft" arm_use_neon=false build_static=true no_madvise_syscall=true'
           - arch: arm_cortex-a9_neon
             openwrt: 'target=zynq subtarget=generic'
             target_cpu: arm
@@ -479,7 +479,7 @@ jobs:
           - arch: mipsel_24kc-static
             openwrt: 'target=ramips subtarget=rt305x'
             target_cpu: mipsel
-            extra: 'mips_arch_variant="r2" mips_float_abi="soft" build_static=true'
+            extra: 'mips_arch_variant="r2" mips_float_abi="soft" build_static=true no_madvise_syscall=true'
           - arch: mipsel_mips32
             openwrt: 'target=bcm47xx subtarget=generic'
             target_cpu: mipsel

src/base/allocator/partition_allocator/page_allocator.h

@@ -260,6 +260,8 @@ constexpr PA_COMPONENT_EXPORT(
     PARTITION_ALLOC) bool DecommittedMemoryIsAlwaysZeroed() {
 #if BUILDFLAG(IS_APPLE)
   return false;
+#elif defined(NO_MADVISE_SYSCALL)
+  return false;
 #else
   return true;
 #endif

src/base/allocator/partition_allocator/page_allocator_internals_posix.h

@@ -410,6 +410,9 @@ void DiscardSystemPagesInternal(uintptr_t address, size_t length) {
     ret = madvise(ptr, length, MADV_DONTNEED);
   }
   PA_PCHECK(ret == 0);
+#elif defined(NO_MADVISE_SYSCALL)
+  static_cast<void>(ptr);
+  static_cast<void>(length);
 #else   // BUILDFLAG(IS_APPLE)
   // We have experimented with other flags, but with suboptimal results.
   //
@@ -417,12 +420,7 @@ void DiscardSystemPagesInternal(uintptr_t address, size_t length) {
   // performance benefits unclear.
   //
   // Therefore, we just do the simple thing: MADV_DONTNEED.
-  int ret = madvise(ptr, length, MADV_DONTNEED);
-  if (ret && errno == ENOSYS) {
-    // Ignores when the kernel is built without CONFIG_ADVISE_SYSCALLS
-    return;
-  }
-  PA_PCHECK(ret == 0);
+  PA_PCHECK(0 == madvise(ptr, length, MADV_DONTNEED));
 #endif  // BUILDFLAG(IS_APPLE)
 }
 

src/build/config/openwrt/BUILD.gn

@@ -14,6 +14,8 @@ assert(current_os == "openwrt")
 
 declare_args() {
   build_static = false
+
+  no_madvise_syscall = false
 }
 
 # This is included by reference in the //build/config/compiler config that
@@ -39,6 +41,10 @@ config("compiler") {
     ldflags += [ "-Wl,--dynamic-linker=/lib/ld-musl-mipsel-sf.so.1" ]
   }
 
+  if (no_madvise_syscall) {
+    defines += [ "NO_MADVISE_SYSCALL" ]
+  }
+
   abi = "musl"
   if (current_cpu == "arm") {
     abi = "muslgnueabi"

src/net/BUILD.gn

@@ -1818,8 +1818,6 @@ executable("naive") {
     "tools/naive/redirect_resolver.cc",
     "tools/naive/socks5_server_socket.cc",
     "tools/naive/socks5_server_socket.h",
-    "tools/naive/partition_alloc_support.cc",
-    "tools/naive/partition_alloc_support.h",
   ]
 
   deps = [

src/net/tools/naive/naive_proxy_bin.cc

@@ -9,14 +9,18 @@
 #include <memory>
 #include <string>
 
+#include "base/allocator/allocator_check.h"
 #include "base/allocator/partition_alloc_support.h"
+#include "base/allocator/partition_allocator/shim/allocator_shim.h"
 #include "base/at_exit.h"
+#include "base/check.h"
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/files/file_path.h"
 #include "base/json/json_file_value_serializer.h"
 #include "base/json/json_writer.h"
 #include "base/logging.h"
+#include "base/process/memory.h"
 #include "base/rand_util.h"
 #include "base/run_loop.h"
 #include "base/strings/escape.h"
@@ -61,7 +65,6 @@
 #include "net/tools/naive/naive_protocol.h"
 #include "net/tools/naive/naive_proxy.h"
 #include "net/tools/naive/naive_proxy_delegate.h"
-#include "net/tools/naive/partition_alloc_support.h"
 #include "net/tools/naive/redirect_resolver.h"
 #include "net/traffic_annotation/network_traffic_annotation.h"
 #include "net/url_request/url_request_context.h"
@@ -71,6 +74,7 @@
 #include "url/url_util.h"
 
 #if BUILDFLAG(IS_APPLE)
+#include "base/allocator/early_zone_registration_mac.h"
 #include "base/mac/scoped_nsautorelease_pool.h"
 #endif
 
@@ -526,12 +530,70 @@ std::unique_ptr<URLRequestContext> BuildURLRequestContext(
 }  // namespace net
 
 int main(int argc, char* argv[]) {
-  naive_partition_alloc_support::ReconfigureEarly();
+  // chrome/app/chrome_exe_main_mac.cc: main()
+#if BUILDFLAG(IS_APPLE)
+  partition_alloc::EarlyMallocZoneRegistration();
+#endif
+
+  // content/app/content_main.cc: RunContentProcess()
+#if BUILDFLAG(IS_MAC)
+  base::mac::ScopedNSAutoreleasePool pool;
+#endif
+
+  // content/app/content_main.cc: RunContentProcess()
+#if BUILDFLAG(IS_APPLE) && BUILDFLAG(USE_ALLOCATOR_SHIM)
+  // The static initializer function for initializing PartitionAlloc
+  // InitializeDefaultMallocZoneWithPartitionAlloc() would be removed by the
+  // linker if allocator_shim.o is not referenced by the following call,
+  // resulting in undefined behavior of accessing uninitialized TLS
+  // data in PurgeCurrentThread() when PA is enabled.
+  allocator_shim::InitializeAllocatorShim();
+#endif
+
+  // content/app/content_main.cc: RunContentProcess()
+  base::EnableTerminationOnOutOfMemory();
+
+  auto multiple_listens = std::make_unique<MultipleListenCollector>();
+  MultipleListenCollector& multiple_listens_ref = *multiple_listens;
+  base::CommandLine::SetDuplicateSwitchHandler(std::move(multiple_listens));
+
+  // content/app/content_main.cc: RunContentProcess()
+  base::CommandLine::Init(argc, argv);
+
+  // content/app/content_main.cc: RunContentProcess()
+  base::EnableTerminationOnHeapCorruption();
+
+  // content/app/content_main.cc: RunContentProcess()
+  //   content/app/content_main_runner_impl.cc: Initialize()
+  base::AtExitManager exit_manager;
+  std::string process_type = "";
+  base::allocator::PartitionAllocSupport::Get()->ReconfigureEarlyish(
+      process_type);
+
+  // content/app/content_main.cc: RunContentProcess()
+  //   content/app/content_main_runner_impl.cc: Initialize()
+  // If we are on a platform where the default allocator is overridden (e.g.
+  // with PartitionAlloc on most platforms) smoke-tests that the overriding
+  // logic is working correctly. If not causes a hard crash, as its unexpected
+  // absence has security implications.
+  CHECK(base::allocator::IsAllocatorInitialized());
+
+  // content/app/content_main.cc: RunContentProcess()
+  //   content/app/content_main_runner_impl.cc: Run()
+  base::FeatureList::InitializeInstance(
+      "PartitionConnectionsByNetworkIsolationKey", std::string());
+
+  base::allocator::PartitionAllocSupport::Get()
+      ->ReconfigureAfterFeatureListInit(/*process_type=*/"");
+
+  base::SingleThreadTaskExecutor io_task_executor(base::MessagePumpType::IO);
+  base::ThreadPoolInstance::CreateAndStartWithDefaultParams("naive");
+
+  base::allocator::PartitionAllocSupport::Get()->ReconfigureAfterTaskRunnerInit(
+      process_type);
 
   url::AddStandardScheme("quic",
                          url::SCHEME_WITH_HOST_PORT_AND_USER_INFORMATION);
-  base::FeatureList::InitializeInstance(
-      "PartitionConnectionsByNetworkIsolationKey", std::string());
   net::ClientSocketPoolManager::set_max_sockets_per_pool(
       net::HttpNetworkSession::NORMAL_SOCKET_POOL,
       kDefaultMaxSocketsPerPool * kExpectedMaxUsers);
@@ -542,20 +604,6 @@ int main(int argc, char* argv[]) {
       net::HttpNetworkSession::NORMAL_SOCKET_POOL,
       kDefaultMaxSocketsPerGroup * kExpectedMaxUsers);
 
-  base::allocator::PartitionAllocSupport::Get()
-      ->ReconfigureAfterFeatureListInit(/*process_type=*/"");
-
-#if BUILDFLAG(IS_APPLE)
-  base::mac::ScopedNSAutoreleasePool pool;
-#endif
-
-  base::AtExitManager exit_manager;
-
-  auto multiple_listens = std::make_unique<MultipleListenCollector>();
-  MultipleListenCollector& multiple_listens_ref = *multiple_listens;
-  base::CommandLine::SetDuplicateSwitchHandler(std::move(multiple_listens));
-  base::CommandLine::Init(argc, argv);
-
   CommandLine cmdline;
 
   Params params;
@@ -577,12 +625,6 @@ int main(int argc, char* argv[]) {
   }
   CHECK(logging::InitLogging(params.log_settings));
 
-  base::SingleThreadTaskExecutor io_task_executor(base::MessagePumpType::IO);
-  base::ThreadPoolInstance::CreateAndStartWithDefaultParams("naive");
-
-  base::allocator::PartitionAllocSupport::Get()
-      ->ReconfigureAfterTaskRunnerInit(/*process_type=*/"");
-
   if (!params.ssl_key_path.empty()) {
     net::SSLClientSocket::SetSSLKeyLogger(
         std::make_unique<net::SSLKeyLoggerImpl>(params.ssl_key_path));

src/net/tools/naive/partition_alloc_support.cc

@@ -1,60 +0,0 @@
-// Copyright 2021 The Chromium Authors
-// Copyright 2022 klzgrad <kizdiv@gmail.com>.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "net/tools/naive/partition_alloc_support.h"
-
-#include "base/allocator/allocator_check.h"
-#include "base/allocator/partition_alloc_support.h"
-#include "base/allocator/partition_allocator/shim/allocator_shim.h"
-#include "base/check.h"
-#include "base/process/memory.h"
-#include "build/build_config.h"
-
-#if BUILDFLAG(IS_APPLE)
-#include "base/allocator/early_zone_registration_mac.h"
-#endif
-
-namespace naive_partition_alloc_support {
-
-void ReconfigureEarly() {
-  // chrome/app/chrome_exe_main_mac.cc: main()
-#if BUILDFLAG(IS_APPLE)
-  partition_alloc::EarlyMallocZoneRegistration();
-#endif
-
-  // content/app/content_main.cc: RunContentProcess()
-#if BUILDFLAG(IS_APPLE) && BUILDFLAG(USE_ALLOCATOR_SHIM)
-  // The static initializer function for initializing PartitionAlloc
-  // InitializeDefaultMallocZoneWithPartitionAlloc() would be removed by the
-  // linker if allocator_shim.o is not referenced by the following call,
-  // resulting in undefined behavior of accessing uninitialized TLS
-  // data in PurgeCurrentThread() when PA is enabled.
-  allocator_shim::InitializeAllocatorShim();
-#endif
-
-  // content/app/content_main.cc: RunContentProcess()
-  base::EnableTerminationOnOutOfMemory();
-
-  // content/app/content_main.cc: RunContentProcess()
-  base::EnableTerminationOnHeapCorruption();
-
-  // content/app/content_main.cc: RunContentProcess()
-  //   content/app/content_main_runner_impl.cc: Initialize()
-  //     ReconfigureEarlyish():
-  // These initializations are only relevant for PartitionAlloc-Everywhere
-  // builds.
-  base::allocator::PartitionAllocSupport::Get()->ReconfigureEarlyish(
-      /*process_type=*/"");
-
-  // content/app/content_main.cc: RunContentProcess()
-  //   content/app/content_main_runner_impl.cc: Initialize()
-  // If we are on a platform where the default allocator is overridden (e.g.
-  // with PartitionAlloc on most platforms) smoke-tests that the overriding
-  // logic is working correctly. If not causes a hard crash, as its unexpected
-  // absence has security implications.
-  CHECK(base::allocator::IsAllocatorInitialized());
-}
-
-}  // namespace naive_partition_alloc_support

src/net/tools/naive/partition_alloc_support.h

@@ -1,15 +0,0 @@
-// Copyright 2021 The Chromium Authors
-// Copyright 2022 klzgrad <kizdiv@gmail.com>.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef NET_TOOLS_NAIVE_PARTITION_ALLOC_SUPPORT_H_
-#define NET_TOOLS_NAIVE_PARTITION_ALLOC_SUPPORT_H_
-
-namespace naive_partition_alloc_support {
-
-void ReconfigureEarly();
-
-}  // namespace naive_partition_alloc_support
-
-#endif  // NET_TOOLS_NAIVE_PARTITION_ALLOC_SUPPORT_H_