1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "content/child/child_thread.h" 6 7 #include <signal.h> 8 9 #include <string> 10 11 #include "base/allocator/allocator_extension.h" 12 #include "base/base_switches.h" 13 #include "base/basictypes.h" 14 #include "base/command_line.h" 15 #include "base/debug/leak_annotations.h" 16 #include "base/lazy_instance.h" 17 #include "base/logging.h" 18 #include "base/message_loop/message_loop.h" 19 #include "base/message_loop/timer_slack.h" 20 #include "base/process/kill.h" 21 #include "base/process/process_handle.h" 22 #include "base/strings/string_number_conversions.h" 23 #include "base/strings/string_util.h" 24 #include "base/synchronization/condition_variable.h" 25 #include "base/synchronization/lock.h" 26 #include "base/threading/thread_local.h" 27 #include "base/tracked_objects.h" 28 #include "components/tracing/child_trace_message_filter.h" 29 #include "content/child/child_histogram_message_filter.h" 30 #include "content/child/child_process.h" 31 #include "content/child/child_resource_message_filter.h" 32 #include "content/child/child_shared_bitmap_manager.h" 33 #include "content/child/fileapi/file_system_dispatcher.h" 34 #include "content/child/fileapi/webfilesystem_impl.h" 35 #include "content/child/mojo/mojo_application.h" 36 #include "content/child/power_monitor_broadcast_source.h" 37 #include "content/child/quota_dispatcher.h" 38 #include "content/child/quota_message_filter.h" 39 #include "content/child/resource_dispatcher.h" 40 #include "content/child/service_worker/service_worker_message_filter.h" 41 #include "content/child/socket_stream_dispatcher.h" 42 #include "content/child/thread_safe_sender.h" 43 #include "content/child/websocket_dispatcher.h" 44 #include "content/common/child_process_messages.h" 45 #include "content/public/common/content_switches.h" 46 #include "ipc/ipc_logging.h" 47 #include "ipc/ipc_switches.h" 48 #include "ipc/ipc_sync_channel.h" 49 #include "ipc/ipc_sync_message_filter.h" 50 #include "ipc/mojo/ipc_channel_mojo.h" 51 52 #if defined(OS_WIN) 53 #include "content/common/handle_enumerator_win.h" 54 #endif 55 56 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED) 57 #include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h" 58 #endif 59 60 using tracked_objects::ThreadData; 61 62 namespace content { 63 namespace { 64 65 // How long to wait for a connection to the browser process before giving up. 66 const int kConnectionTimeoutS = 15; 67 68 base::LazyInstance<base::ThreadLocalPointer<ChildThread> > g_lazy_tls = 69 LAZY_INSTANCE_INITIALIZER; 70 71 // This isn't needed on Windows because there the sandbox's job object 72 // terminates child processes automatically. For unsandboxed processes (i.e. 73 // plugins), PluginThread has EnsureTerminateMessageFilter. 74 #if defined(OS_POSIX) 75 76 // TODO(earthdok): Re-enable on CrOS http://crbug.com/360622 77 #if (defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \ 78 defined(THREAD_SANITIZER)) && !defined(OS_CHROMEOS) 79 // A thread delegate that waits for |duration| and then exits the process with 80 // _exit(0). 81 class WaitAndExitDelegate : public base::PlatformThread::Delegate { 82 public: 83 explicit WaitAndExitDelegate(base::TimeDelta duration) 84 : duration_(duration) {} 85 virtual ~WaitAndExitDelegate() OVERRIDE {} 86 87 virtual void ThreadMain() OVERRIDE { 88 base::PlatformThread::Sleep(duration_); 89 _exit(0); 90 } 91 92 private: 93 const base::TimeDelta duration_; 94 DISALLOW_COPY_AND_ASSIGN(WaitAndExitDelegate); 95 }; 96 97 bool CreateWaitAndExitThread(base::TimeDelta duration) { 98 scoped_ptr<WaitAndExitDelegate> delegate(new WaitAndExitDelegate(duration)); 99 100 const bool thread_created = 101 base::PlatformThread::CreateNonJoinable(0, delegate.get()); 102 if (!thread_created) 103 return false; 104 105 // A non joinable thread has been created. The thread will either terminate 106 // the process or will be terminated by the process. Therefore, keep the 107 // delegate object alive for the lifetime of the process. 108 WaitAndExitDelegate* leaking_delegate = delegate.release(); 109 ANNOTATE_LEAKING_OBJECT_PTR(leaking_delegate); 110 ignore_result(leaking_delegate); 111 return true; 112 } 113 #endif 114 115 class SuicideOnChannelErrorFilter : public IPC::MessageFilter { 116 public: 117 // IPC::MessageFilter 118 virtual void OnChannelError() OVERRIDE { 119 // For renderer/worker processes: 120 // On POSIX, at least, one can install an unload handler which loops 121 // forever and leave behind a renderer process which eats 100% CPU forever. 122 // 123 // This is because the terminate signals (ViewMsg_ShouldClose and the error 124 // from the IPC sender) are routed to the main message loop but never 125 // processed (because that message loop is stuck in V8). 126 // 127 // One could make the browser SIGKILL the renderers, but that leaves open a 128 // large window where a browser failure (or a user, manually terminating 129 // the browser because "it's stuck") will leave behind a process eating all 130 // the CPU. 131 // 132 // So, we install a filter on the sender so that we can process this event 133 // here and kill the process. 134 // TODO(earthdok): Re-enable on CrOS http://crbug.com/360622 135 #if (defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \ 136 defined(THREAD_SANITIZER)) && !defined(OS_CHROMEOS) 137 // Some sanitizer tools rely on exit handlers (e.g. to run leak detection, 138 // or dump code coverage data to disk). Instead of exiting the process 139 // immediately, we give it 60 seconds to run exit handlers. 140 CHECK(CreateWaitAndExitThread(base::TimeDelta::FromSeconds(60))); 141 #if defined(LEAK_SANITIZER) 142 // Invoke LeakSanitizer early to avoid detecting shutdown-only leaks. If 143 // leaks are found, the process will exit here. 144 __lsan_do_leak_check(); 145 #endif 146 #else 147 _exit(0); 148 #endif 149 } 150 151 protected: 152 virtual ~SuicideOnChannelErrorFilter() {} 153 }; 154 155 #endif // OS(POSIX) 156 157 #if defined(OS_ANDROID) 158 ChildThread* g_child_thread = NULL; 159 160 // A lock protects g_child_thread. 161 base::LazyInstance<base::Lock> g_lazy_child_thread_lock = 162 LAZY_INSTANCE_INITIALIZER; 163 164 // base::ConditionVariable has an explicit constructor that takes 165 // a base::Lock pointer as parameter. The base::DefaultLazyInstanceTraits 166 // doesn't handle the case. Thus, we need our own class here. 167 struct CondVarLazyInstanceTraits { 168 static const bool kRegisterOnExit = true; 169 #ifndef NDEBUG 170 static const bool kAllowedToAccessOnNonjoinableThread = false; 171 #endif 172 173 static base::ConditionVariable* New(void* instance) { 174 return new (instance) base::ConditionVariable( 175 g_lazy_child_thread_lock.Pointer()); 176 } 177 static void Delete(base::ConditionVariable* instance) { 178 instance->~ConditionVariable(); 179 } 180 }; 181 182 // A condition variable that synchronize threads initializing and waiting 183 // for g_child_thread. 184 base::LazyInstance<base::ConditionVariable, CondVarLazyInstanceTraits> 185 g_lazy_child_thread_cv = LAZY_INSTANCE_INITIALIZER; 186 187 void QuitMainThreadMessageLoop() { 188 base::MessageLoop::current()->Quit(); 189 } 190 191 #endif 192 193 } // namespace 194 195 ChildThread::Options::Options() 196 : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII( 197 switches::kProcessChannelID)), 198 use_mojo_channel(false) {} 199 200 ChildThread::Options::Options(bool mojo) 201 : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII( 202 switches::kProcessChannelID)), 203 use_mojo_channel(mojo) {} 204 205 206 ChildThread::ChildThreadMessageRouter::ChildThreadMessageRouter( 207 IPC::Sender* sender) 208 : sender_(sender) {} 209 210 bool ChildThread::ChildThreadMessageRouter::Send(IPC::Message* msg) { 211 return sender_->Send(msg); 212 } 213 214 ChildThread::ChildThread() 215 : router_(this), 216 in_browser_process_(false), 217 channel_connected_factory_(this) { 218 Init(Options()); 219 } 220 221 ChildThread::ChildThread(const Options& options) 222 : router_(this), 223 in_browser_process_(true), 224 channel_connected_factory_(this) { 225 Init(options); 226 } 227 228 scoped_ptr<IPC::SyncChannel> ChildThread::CreateChannel(bool use_mojo_channel) { 229 if (use_mojo_channel) { 230 VLOG(1) << "Mojo is enabled on child"; 231 return IPC::SyncChannel::Create( 232 IPC::ChannelMojo::CreateClientFactory(channel_name_), 233 this, 234 ChildProcess::current()->io_message_loop_proxy(), 235 true, 236 ChildProcess::current()->GetShutDownEvent()); 237 } 238 239 VLOG(1) << "Mojo is disabled on child"; 240 return IPC::SyncChannel::Create( 241 channel_name_, 242 IPC::Channel::MODE_CLIENT, 243 this, 244 ChildProcess::current()->io_message_loop_proxy(), 245 true, 246 ChildProcess::current()->GetShutDownEvent()); 247 } 248 249 void ChildThread::Init(const Options& options) { 250 channel_name_ = options.channel_name; 251 252 g_lazy_tls.Pointer()->Set(this); 253 on_channel_error_called_ = false; 254 message_loop_ = base::MessageLoop::current(); 255 #ifdef IPC_MESSAGE_LOG_ENABLED 256 // We must make sure to instantiate the IPC Logger *before* we create the 257 // channel, otherwise we can get a callback on the IO thread which creates 258 // the logger, and the logger does not like being created on the IO thread. 259 IPC::Logging::GetInstance(); 260 #endif 261 channel_ = CreateChannel(options.use_mojo_channel); 262 #ifdef IPC_MESSAGE_LOG_ENABLED 263 if (!in_browser_process_) 264 IPC::Logging::GetInstance()->SetIPCSender(this); 265 #endif 266 267 mojo_application_.reset(new MojoApplication); 268 269 sync_message_filter_ = 270 new IPC::SyncMessageFilter(ChildProcess::current()->GetShutDownEvent()); 271 thread_safe_sender_ = new ThreadSafeSender( 272 base::MessageLoopProxy::current().get(), sync_message_filter_.get()); 273 274 resource_dispatcher_.reset(new ResourceDispatcher(this)); 275 socket_stream_dispatcher_.reset(new SocketStreamDispatcher()); 276 websocket_dispatcher_.reset(new WebSocketDispatcher); 277 file_system_dispatcher_.reset(new FileSystemDispatcher()); 278 279 histogram_message_filter_ = new ChildHistogramMessageFilter(); 280 resource_message_filter_ = 281 new ChildResourceMessageFilter(resource_dispatcher()); 282 283 service_worker_message_filter_ = 284 new ServiceWorkerMessageFilter(thread_safe_sender_.get()); 285 286 quota_message_filter_ = 287 new QuotaMessageFilter(thread_safe_sender_.get()); 288 quota_dispatcher_.reset(new QuotaDispatcher(thread_safe_sender_.get(), 289 quota_message_filter_.get())); 290 291 channel_->AddFilter(histogram_message_filter_.get()); 292 channel_->AddFilter(sync_message_filter_.get()); 293 channel_->AddFilter(resource_message_filter_.get()); 294 channel_->AddFilter(quota_message_filter_->GetFilter()); 295 channel_->AddFilter(service_worker_message_filter_->GetFilter()); 296 297 if (!base::CommandLine::ForCurrentProcess()->HasSwitch( 298 switches::kSingleProcess)) { 299 // In single process mode, browser-side tracing will cover the whole 300 // process including renderers. 301 channel_->AddFilter(new tracing::ChildTraceMessageFilter( 302 ChildProcess::current()->io_message_loop_proxy())); 303 } 304 305 // In single process mode we may already have a power monitor 306 if (!base::PowerMonitor::Get()) { 307 scoped_ptr<PowerMonitorBroadcastSource> power_monitor_source( 308 new PowerMonitorBroadcastSource()); 309 channel_->AddFilter(power_monitor_source->GetMessageFilter()); 310 311 power_monitor_.reset(new base::PowerMonitor( 312 power_monitor_source.PassAs<base::PowerMonitorSource>())); 313 } 314 315 #if defined(OS_POSIX) 316 // Check that --process-type is specified so we don't do this in unit tests 317 // and single-process mode. 318 if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kProcessType)) 319 channel_->AddFilter(new SuicideOnChannelErrorFilter()); 320 #endif 321 322 int connection_timeout = kConnectionTimeoutS; 323 std::string connection_override = 324 base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII( 325 switches::kIPCConnectionTimeout); 326 if (!connection_override.empty()) { 327 int temp; 328 if (base::StringToInt(connection_override, &temp)) 329 connection_timeout = temp; 330 } 331 332 base::MessageLoop::current()->PostDelayedTask( 333 FROM_HERE, 334 base::Bind(&ChildThread::EnsureConnected, 335 channel_connected_factory_.GetWeakPtr()), 336 base::TimeDelta::FromSeconds(connection_timeout)); 337 338 #if defined(OS_ANDROID) 339 { 340 base::AutoLock lock(g_lazy_child_thread_lock.Get()); 341 g_child_thread = this; 342 } 343 // Signalling without locking is fine here because only 344 // one thread can wait on the condition variable. 345 g_lazy_child_thread_cv.Get().Signal(); 346 #endif 347 348 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED) 349 trace_memory_controller_.reset(new base::debug::TraceMemoryController( 350 message_loop_->message_loop_proxy(), 351 ::HeapProfilerWithPseudoStackStart, 352 ::HeapProfilerStop, 353 ::GetHeapProfile)); 354 #endif 355 356 shared_bitmap_manager_.reset( 357 new ChildSharedBitmapManager(thread_safe_sender())); 358 } 359 360 ChildThread::~ChildThread() { 361 #ifdef IPC_MESSAGE_LOG_ENABLED 362 IPC::Logging::GetInstance()->SetIPCSender(NULL); 363 #endif 364 365 channel_->RemoveFilter(histogram_message_filter_.get()); 366 channel_->RemoveFilter(sync_message_filter_.get()); 367 368 // The ChannelProxy object caches a pointer to the IPC thread, so need to 369 // reset it as it's not guaranteed to outlive this object. 370 // NOTE: this also has the side-effect of not closing the main IPC channel to 371 // the browser process. This is needed because this is the signal that the 372 // browser uses to know that this process has died, so we need it to be alive 373 // until this process is shut down, and the OS closes the handle 374 // automatically. We used to watch the object handle on Windows to do this, 375 // but it wasn't possible to do so on POSIX. 376 channel_->ClearIPCTaskRunner(); 377 g_lazy_tls.Pointer()->Set(NULL); 378 } 379 380 void ChildThread::Shutdown() { 381 // Delete objects that hold references to blink so derived classes can 382 // safely shutdown blink in their Shutdown implementation. 383 file_system_dispatcher_.reset(); 384 quota_dispatcher_.reset(); 385 WebFileSystemImpl::DeleteThreadSpecificInstance(); 386 } 387 388 void ChildThread::OnChannelConnected(int32 peer_pid) { 389 channel_connected_factory_.InvalidateWeakPtrs(); 390 } 391 392 void ChildThread::OnChannelError() { 393 set_on_channel_error_called(true); 394 base::MessageLoop::current()->Quit(); 395 } 396 397 bool ChildThread::Send(IPC::Message* msg) { 398 DCHECK(base::MessageLoop::current() == message_loop()); 399 if (!channel_) { 400 delete msg; 401 return false; 402 } 403 404 return channel_->Send(msg); 405 } 406 407 MessageRouter* ChildThread::GetRouter() { 408 DCHECK(base::MessageLoop::current() == message_loop()); 409 return &router_; 410 } 411 412 base::SharedMemory* ChildThread::AllocateSharedMemory(size_t buf_size) { 413 return AllocateSharedMemory(buf_size, this); 414 } 415 416 // static 417 base::SharedMemory* ChildThread::AllocateSharedMemory( 418 size_t buf_size, 419 IPC::Sender* sender) { 420 scoped_ptr<base::SharedMemory> shared_buf; 421 #if defined(OS_WIN) 422 shared_buf.reset(new base::SharedMemory); 423 if (!shared_buf->CreateAndMapAnonymous(buf_size)) { 424 NOTREACHED(); 425 return NULL; 426 } 427 #else 428 // On POSIX, we need to ask the browser to create the shared memory for us, 429 // since this is blocked by the sandbox. 430 base::SharedMemoryHandle shared_mem_handle; 431 if (sender->Send(new ChildProcessHostMsg_SyncAllocateSharedMemory( 432 buf_size, &shared_mem_handle))) { 433 if (base::SharedMemory::IsHandleValid(shared_mem_handle)) { 434 shared_buf.reset(new base::SharedMemory(shared_mem_handle, false)); 435 if (!shared_buf->Map(buf_size)) { 436 NOTREACHED() << "Map failed"; 437 return NULL; 438 } 439 } else { 440 NOTREACHED() << "Browser failed to allocate shared memory"; 441 return NULL; 442 } 443 } else { 444 NOTREACHED() << "Browser allocation request message failed"; 445 return NULL; 446 } 447 #endif 448 return shared_buf.release(); 449 } 450 451 bool ChildThread::OnMessageReceived(const IPC::Message& msg) { 452 if (mojo_application_->OnMessageReceived(msg)) 453 return true; 454 455 // Resource responses are sent to the resource dispatcher. 456 if (resource_dispatcher_->OnMessageReceived(msg)) 457 return true; 458 if (socket_stream_dispatcher_->OnMessageReceived(msg)) 459 return true; 460 if (websocket_dispatcher_->OnMessageReceived(msg)) 461 return true; 462 if (file_system_dispatcher_->OnMessageReceived(msg)) 463 return true; 464 465 bool handled = true; 466 IPC_BEGIN_MESSAGE_MAP(ChildThread, msg) 467 IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown) 468 #if defined(IPC_MESSAGE_LOG_ENABLED) 469 IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIPCLoggingEnabled, 470 OnSetIPCLoggingEnabled) 471 #endif 472 IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProfilerStatus, 473 OnSetProfilerStatus) 474 IPC_MESSAGE_HANDLER(ChildProcessMsg_GetChildProfilerData, 475 OnGetChildProfilerData) 476 IPC_MESSAGE_HANDLER(ChildProcessMsg_DumpHandles, OnDumpHandles) 477 IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProcessBackgrounded, 478 OnProcessBackgrounded) 479 #if defined(USE_TCMALLOC) 480 IPC_MESSAGE_HANDLER(ChildProcessMsg_GetTcmallocStats, OnGetTcmallocStats) 481 #endif 482 IPC_MESSAGE_UNHANDLED(handled = false) 483 IPC_END_MESSAGE_MAP() 484 485 if (handled) 486 return true; 487 488 if (msg.routing_id() == MSG_ROUTING_CONTROL) 489 return OnControlMessageReceived(msg); 490 491 return router_.OnMessageReceived(msg); 492 } 493 494 bool ChildThread::OnControlMessageReceived(const IPC::Message& msg) { 495 return false; 496 } 497 498 void ChildThread::OnShutdown() { 499 base::MessageLoop::current()->Quit(); 500 } 501 502 #if defined(IPC_MESSAGE_LOG_ENABLED) 503 void ChildThread::OnSetIPCLoggingEnabled(bool enable) { 504 if (enable) 505 IPC::Logging::GetInstance()->Enable(); 506 else 507 IPC::Logging::GetInstance()->Disable(); 508 } 509 #endif // IPC_MESSAGE_LOG_ENABLED 510 511 void ChildThread::OnSetProfilerStatus(ThreadData::Status status) { 512 ThreadData::InitializeAndSetTrackingStatus(status); 513 } 514 515 void ChildThread::OnGetChildProfilerData(int sequence_number) { 516 tracked_objects::ProcessDataSnapshot process_data; 517 ThreadData::Snapshot(false, &process_data); 518 519 Send(new ChildProcessHostMsg_ChildProfilerData(sequence_number, 520 process_data)); 521 } 522 523 void ChildThread::OnDumpHandles() { 524 #if defined(OS_WIN) 525 scoped_refptr<HandleEnumerator> handle_enum( 526 new HandleEnumerator( 527 base::CommandLine::ForCurrentProcess()->HasSwitch( 528 switches::kAuditAllHandles))); 529 handle_enum->EnumerateHandles(); 530 Send(new ChildProcessHostMsg_DumpHandlesDone); 531 #else 532 NOTIMPLEMENTED(); 533 #endif 534 } 535 536 #if defined(USE_TCMALLOC) 537 void ChildThread::OnGetTcmallocStats() { 538 std::string result; 539 char buffer[1024 * 32]; 540 base::allocator::GetStats(buffer, sizeof(buffer)); 541 result.append(buffer); 542 Send(new ChildProcessHostMsg_TcmallocStats(result)); 543 } 544 #endif 545 546 ChildThread* ChildThread::current() { 547 return g_lazy_tls.Pointer()->Get(); 548 } 549 550 #if defined(OS_ANDROID) 551 // The method must NOT be called on the child thread itself. 552 // It may block the child thread if so. 553 void ChildThread::ShutdownThread() { 554 DCHECK(!ChildThread::current()) << 555 "this method should NOT be called from child thread itself"; 556 { 557 base::AutoLock lock(g_lazy_child_thread_lock.Get()); 558 while (!g_child_thread) 559 g_lazy_child_thread_cv.Get().Wait(); 560 } 561 DCHECK_NE(base::MessageLoop::current(), g_child_thread->message_loop()); 562 g_child_thread->message_loop()->PostTask( 563 FROM_HERE, base::Bind(&QuitMainThreadMessageLoop)); 564 } 565 #endif 566 567 void ChildThread::OnProcessFinalRelease() { 568 if (on_channel_error_called_) { 569 base::MessageLoop::current()->Quit(); 570 return; 571 } 572 573 // The child process shutdown sequence is a request response based mechanism, 574 // where we send out an initial feeler request to the child process host 575 // instance in the browser to verify if it's ok to shutdown the child process. 576 // The browser then sends back a response if it's ok to shutdown. This avoids 577 // race conditions if the process refcount is 0 but there's an IPC message 578 // inflight that would addref it. 579 Send(new ChildProcessHostMsg_ShutdownRequest); 580 } 581 582 void ChildThread::EnsureConnected() { 583 VLOG(0) << "ChildThread::EnsureConnected()"; 584 base::KillProcess(base::GetCurrentProcessHandle(), 0, false); 585 } 586 587 void ChildThread::OnProcessBackgrounded(bool background) { 588 // Set timer slack to maximum on main thread when in background. 589 base::TimerSlack timer_slack = base::TIMER_SLACK_NONE; 590 if (background) 591 timer_slack = base::TIMER_SLACK_MAXIMUM; 592 base::MessageLoop::current()->SetTimerSlack(timer_slack); 593 } 594 595 } // namespace content 596