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content / browser / child_process_launcher_helper_linux.cc [blame]
// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/command_line.h"
#include "base/path_service.h"
#include "base/posix/global_descriptors.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "content/browser/child_process_launcher.h"
#include "content/browser/child_process_launcher_helper.h"
#include "content/browser/child_process_launcher_helper_posix.h"
#include "content/browser/sandbox_host_linux.h"
#include "content/browser/zygote_host/zygote_host_impl_linux.h"
#include "content/common/zygote/zygote_communication_linux.h"
#include "content/public/browser/child_process_launcher_utils.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/common/content_client.h"
#include "content/public/common/content_constants.h"
#include "content/public/common/content_features.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/result_codes.h"
#include "content/public/common/sandboxed_process_launcher_delegate.h"
#include "content/public/common/zygote/sandbox_support_linux.h"
#include "content/public/common/zygote/zygote_handle.h"
#include "sandbox/policy/linux/sandbox_linux.h"
namespace content {
namespace internal {
std::optional<mojo::NamedPlatformChannel>
ChildProcessLauncherHelper::CreateNamedPlatformChannelOnLauncherThread() {
DCHECK(CurrentlyOnProcessLauncherTaskRunner());
return std::nullopt;
}
void ChildProcessLauncherHelper::BeforeLaunchOnClientThread() {
DCHECK(client_task_runner_->RunsTasksInCurrentSequence());
}
std::unique_ptr<FileMappedForLaunch>
ChildProcessLauncherHelper::GetFilesToMap() {
DCHECK(CurrentlyOnProcessLauncherTaskRunner());
return CreateDefaultPosixFilesToMap(
child_process_id(), mojo_channel_->remote_endpoint(),
file_data_->files_to_preload, GetProcessType(), command_line());
}
bool ChildProcessLauncherHelper::IsUsingLaunchOptions() {
return !GetZygoteForLaunch();
}
bool ChildProcessLauncherHelper::BeforeLaunchOnLauncherThread(
PosixFileDescriptorInfo& files_to_register,
base::LaunchOptions* options) {
if (options) {
DCHECK(!GetZygoteForLaunch());
// Convert FD mapping to FileHandleMappingVector
options->fds_to_remap = files_to_register.GetMappingWithIDAdjustment(
base::GlobalDescriptors::kBaseDescriptor);
if (GetProcessType() == switches::kRendererProcess) {
const int sandbox_fd = SandboxHostLinux::GetInstance()->GetChildSocket();
options->fds_to_remap.emplace_back(sandbox_fd, GetSandboxFD());
}
options->environment = delegate_->GetEnvironment();
} else {
DCHECK(GetZygoteForLaunch());
// Environment variables could be supported in the future, but are not
// currently supported when launching with the zygote.
DCHECK(delegate_->GetEnvironment().empty());
}
return true;
}
ChildProcessLauncherHelper::Process
ChildProcessLauncherHelper::LaunchProcessOnLauncherThread(
const base::LaunchOptions* options,
std::unique_ptr<FileMappedForLaunch> files_to_register,
bool* is_synchronous_launch,
int* launch_result) {
*is_synchronous_launch = true;
Process process;
ZygoteCommunication* zygote_handle = GetZygoteForLaunch();
if (zygote_handle) {
// TODO(crbug.com/40448989): If chrome supported multiple zygotes they could
// be created lazily here, or in the delegate GetZygote() implementations.
// Additionally, the delegate could provide a UseGenericZygote() method.
base::ProcessHandle handle = zygote_handle->ForkRequest(
command_line()->argv(), files_to_register->GetMapping(),
GetProcessType());
*launch_result = LAUNCH_RESULT_SUCCESS;
#if !BUILDFLAG(IS_OPENBSD)
if (handle) {
// It could be a renderer process or an utility process.
int oom_score = content::kMiscOomScore;
if (command_line()->GetSwitchValueASCII(switches::kProcessType) ==
switches::kRendererProcess)
oom_score = content::kLowestRendererOomScore;
ZygoteHostImpl::GetInstance()->AdjustRendererOOMScore(handle, oom_score);
}
#endif
process.process = base::Process(handle);
process.zygote = zygote_handle;
} else {
process.process = base::LaunchProcess(*command_line(), *options);
*launch_result = process.process.IsValid() ? LAUNCH_RESULT_SUCCESS
: LAUNCH_RESULT_FAILURE;
}
#if BUILDFLAG(IS_CHROMEOS)
process_id_ = process.process.Pid();
if (GetProcessType() == switches::kRendererProcess ||
base::FeatureList::IsEnabled(features::kSchedQoSOnResourcedForChrome)) {
process.process.InitializePriority();
}
#endif
return process;
}
void ChildProcessLauncherHelper::AfterLaunchOnLauncherThread(
const ChildProcessLauncherHelper::Process& process,
const base::LaunchOptions* options) {
// Reset any FDs still held open.
file_data_.reset();
}
ChildProcessTerminationInfo ChildProcessLauncherHelper::GetTerminationInfo(
const ChildProcessLauncherHelper::Process& process,
bool known_dead) {
ChildProcessTerminationInfo info;
if (process.zygote) {
info.status = process.zygote->GetTerminationStatus(
process.process.Handle(), known_dead, &info.exit_code);
} else if (known_dead) {
info.status = base::GetKnownDeadTerminationStatus(process.process.Handle(),
&info.exit_code);
} else {
info.status =
base::GetTerminationStatus(process.process.Handle(), &info.exit_code);
}
return info;
}
// static
bool ChildProcessLauncherHelper::TerminateProcess(const base::Process& process,
int exit_code) {
// TODO(crbug.com/40565504): Determine whether we should also call
// EnsureProcessTerminated() to make sure of process-exit, and reap it.
return process.Terminate(exit_code, false);
}
// static
void ChildProcessLauncherHelper::ForceNormalProcessTerminationSync(
ChildProcessLauncherHelper::Process process) {
TRACE_EVENT0("chromeos",
"ChildProcessLauncherHelper::ForceNormalProcessTerminationSync");
DCHECK(CurrentlyOnProcessLauncherTaskRunner());
process.process.Terminate(RESULT_CODE_NORMAL_EXIT, false);
// On POSIX, we must additionally reap the child.
if (process.zygote) {
// If the renderer was created via a zygote, we have to proxy the reaping
// through the zygote process.
process.zygote->EnsureProcessTerminated(process.process.Handle());
} else {
base::EnsureProcessTerminated(std::move(process.process));
}
}
void ChildProcessLauncherHelper::SetProcessPriorityOnLauncherThread(
base::Process process,
base::Process::Priority priority) {
DCHECK(CurrentlyOnProcessLauncherTaskRunner());
if (process.CanSetPriority() && priority_ != priority) {
priority_ = priority;
process.SetPriority(priority);
}
}
ZygoteCommunication* ChildProcessLauncherHelper::GetZygoteForLaunch() {
return base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kNoZygote)
? nullptr
: delegate_->GetZygote();
}
base::File OpenFileToShare(const base::FilePath& path,
base::MemoryMappedFile::Region* region) {
base::FilePath exe_dir;
bool result = base::PathService::Get(base::BasePathKey::DIR_EXE, &exe_dir);
DCHECK(result);
base::File file(exe_dir.Append(path),
base::File::FLAG_OPEN | base::File::FLAG_READ);
*region = base::MemoryMappedFile::Region::kWholeFile;
return file;
}
} // namespace internal
} // namespace content