Reduce resource leak code for StartNaClExecution.

components/nacl/loader/nacl_listener.cc

 // Copyright 2013 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 "components/nacl/loader/nacl_listener.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <stdlib.h>
 #include <string.h>
@@ skipping 318 matching lines @@
 void NaClListener::OnStart(const nacl::NaClStartParams& params) {
   is_started_ = true;
 #if defined(OS_LINUX) || defined(OS_MACOSX)
   int urandom_fd = dup(base::GetUrandomFD());
   if (urandom_fd < 0) {
     LOG(ERROR) << "Failed to dup() the urandom FD";
     return;
   }
   NaClChromeMainSetUrandomFd(urandom_fd);
 #endif
+
+  // Before starting the launching process, verify if FDs/HANDLEs are properly
+  // transferred to here.
+  // These can be stale, if some unexpected error happens in the sender
+  // process. It sends the IPC message regardless of the errors with deferring
+  // the error handle to the callee for releasing FDs/HANDLEs properly.
+  CHECK(params.nexe_file != IPC::InvalidPlatformFileForTransit());
+  CHECK(params.imc_bootstrap_handle != IPC::InvalidPlatformFileForTransit());
+  CHECK(params.irt_handle != IPC::InvalidPlatformFileForTransit());
+#if defined(OS_MACOSX)
+  CHECK(params.mac_shm_fd != IPC::InvalidPlatformFileForTransit());
+#endif
+  CHECK(base::SharedMemory::IsHandleValid(params.crash_info_shmem_handle));
+
   struct NaClApp* nap = NULL;
   NaClChromeMainInit();
 
-  CHECK(base::SharedMemory::IsHandleValid(params.crash_info_shmem_handle));
   crash_info_shmem_.reset(new base::SharedMemory(
       params.crash_info_shmem_handle, false /* not readonly */));
   CHECK(crash_info_shmem_->Map(nacl::kNaClCrashInfoShmemSize));
   NaClSetFatalErrorCallback(&FatalLogHandler);
 
   nap = NaClAppCreate();
   if (nap == NULL) {
     LOG(ERROR) << "NaClAppCreate() failed";
     return;
   }
@@ skipping 42 matching lines @@
   struct NaClChromeMainArgs* args = NaClChromeMainArgsCreate();
   if (args == NULL) {
     LOG(ERROR) << "NaClChromeMainArgsCreate() failed";
     return;
   }
 
 #if defined(OS_LINUX) || defined(OS_MACOSX)
   args->number_of_cores = number_of_cores_;
   args->create_memory_object_func = CreateMemoryObject;
 # if defined(OS_MACOSX)
-  CHECK(params.mac_shm_fd != IPC::InvalidPlatformFileForTransit());
   g_shm_fd = IPC::PlatformFileForTransitToPlatformFile(params.mac_shm_fd);
 # endif
 #endif
 
   DCHECK(params.process_type != nacl::kUnknownNaClProcessType);
-  CHECK(params.irt_handle != IPC::InvalidPlatformFileForTransit());
   NaClHandle irt_handle =
       IPC::PlatformFileForTransitToPlatformFile(params.irt_handle);
 
 #if defined(OS_WIN)
   args->irt_fd = _open_osfhandle(reinterpret_cast<intptr_t>(irt_handle),
                                  _O_RDONLY | _O_BINARY);
   if (args->irt_fd < 0) {
     LOG(ERROR) << "_open_osfhandle() failed";
     return;
   }
 #else
   args->irt_fd = irt_handle;
 #endif
 
   if (params.validation_cache_enabled) {
     // SHA256 block size.
     CHECK_EQ(params.validation_cache_key.length(), (size_t) 64);
     // The cache structure is not freed and exists until the NaCl process exits.
     args->validation_cache = CreateValidationCache(
         new BrowserValidationDBProxy(this), params.validation_cache_key,
         params.version);
   }
 
-  CHECK(params.imc_bootstrap_handle != IPC::InvalidPlatformFileForTransit());
   args->imc_bootstrap_handle =
       IPC::PlatformFileForTransitToPlatformFile(params.imc_bootstrap_handle);
   args->enable_debug_stub = params.enable_debug_stub;
 
   // Now configure parts that depend on process type.
   // Start with stricter settings.
   args->enable_exception_handling = 0;
   args->enable_dyncode_syscalls = 0;
   // pnacl_mode=1 mostly disables things (IRT interfaces and syscalls).
   args->pnacl_mode = 1;
@@ skipping 61 matching lines @@
 }
 
 void NaClListener::OnFileTokenResolved(
     uint64_t token_lo,
     uint64_t token_hi,
     IPC::PlatformFileForTransit ipc_fd,
     base::FilePath file_path) {
   resolved_cb_.Run(ipc_fd, file_path);
   resolved_cb_.Reset();
 }