chromeos: Fix potential crash in SessionManagerClient

chromeos/dbus/session_manager_client.cc

 // 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.
 
 #include "chromeos/dbus/session_manager_client.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <sys/socket.h>
 
@@ skipping 65 matching lines @@
     return;
   }
 
   local_auth_fd->PutValue(sockets[0]);
   local_auth_fd->CheckValidity();
 
   remote_auth_fd->PutValue(sockets[1]);
   remote_auth_fd->CheckValidity();
 }
 
-void HandleDBusError(dbus::ErrorResponse* response) {
-  LOG(ERROR) << "DBus error " << response->ToString();

[achuithb, 2016/08/30 08:56:28]

Add a null check, but please log something if you get a null response.

-}
-
 }  // namespace
 
 // The SessionManagerClient implementation used in production.
 class SessionManagerClientImpl : public SessionManagerClient {
  public:
   SessionManagerClientImpl()
       : session_manager_proxy_(NULL),
         screen_is_locked_(false),
         weak_ptr_factory_(this) {}
 
@@ skipping 405 matching lines @@
     VLOG(1) << "CallRestartJobWithValidFd";
     dbus::MethodCall method_call(login_manager::kSessionManagerInterface,
                                  login_manager::kSessionManagerRestartJob);
     dbus::MessageWriter writer(&method_call);
     writer.AppendFileDescriptor(*remote_auth_fd);
     writer.AppendArrayOfStrings(argv);
 
     // Ownership of local_auth_fd is passed to the callback that is to be
     // called on completion of this method call. This keeps the browser end
     // of the socket-pair alive for the duration of the RPC.
-    session_manager_proxy_->CallMethodWithErrorCallback(
+    session_manager_proxy_->CallMethod(
         &method_call, dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
         base::Bind(&SessionManagerClientImpl::OnRestartJob,
                    weak_ptr_factory_.GetWeakPtr(),
-                   base::Passed(&local_auth_fd)),
-        base::Bind(HandleDBusError));
+                   base::Passed(&local_auth_fd)));
   }
 
   // Called when kSessionManagerRestartJob method is complete.
   // Now that the call is complete, local_auth_fd can be closed and discarded,
   // which will happen automatically when it goes out of scope.
   void OnRestartJob(dbus::ScopedFileDescriptor local_auth_fd,
                     dbus::Response* response) {
     VLOG(1) << "OnRestartJob";
     LOG_IF(ERROR, !response)
         << "Failed to call "
@@ skipping 447 matching lines @@
 
 SessionManagerClient* SessionManagerClient::Create(
     DBusClientImplementationType type) {
   if (type == REAL_DBUS_CLIENT_IMPLEMENTATION)
     return new SessionManagerClientImpl();
   DCHECK_EQ(STUB_DBUS_CLIENT_IMPLEMENTATION, type);
   return new SessionManagerClientStubImpl();
 }
 
 }  // namespace chromeos