[NaCl SDK] nacl_io: Fix use-after-free bug in html5fs

native_client_sdk/src/libraries/nacl_io/passthroughfs/passthrough_fs.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 "nacl_io/passthroughfs/passthrough_fs.h"
 
 #include <errno.h>
 
 #include "nacl_io/kernel_handle.h"
 #include "nacl_io/kernel_wrap_real.h"
 #include "nacl_io/passthroughfs/real_node.h"
 
 namespace nacl_io {
 
 PassthroughFs::PassthroughFs() {
 }
 
 Error PassthroughFs::Init(const FsInitArgs& args) {
   return Filesystem::Init(args);
 }
 
 void PassthroughFs::Destroy() {
 }
 
 Error PassthroughFs::OpenWithMode(const Path& path, int open_flags,
                                   mode_t mode, ScopedNode* out_node) {
   out_node->reset(NULL);
   int real_fd;
-  int error = _real_open(path.Join().c_str(), open_flags, mode, &real_fd);
+  std::string path_str = path.Join();
+  int error = _real_open(path_str.c_str(), open_flags, mode, &real_fd);
   if (error)
     return error;
 
   out_node->reset(new RealNode(this, real_fd, true));
   return 0;
 }
 
 Error PassthroughFs::OpenResource(const Path& path, ScopedNode* out_node) {
   int real_fd;
   out_node->reset(NULL);
-  int error = _real_open_resource(path.Join().c_str(), &real_fd);
+  std::string path_str = path.Join();
+  int error = _real_open_resource(path_str.c_str(), &real_fd);
   if (error)
     return error;
 
   out_node->reset(new RealNode(this, real_fd));
   return 0;
 }
 
 Error PassthroughFs::Unlink(const Path& path) {
   // Not implemented by NaCl.
   return ENOSYS;
 }
 
 Error PassthroughFs::Mkdir(const Path& path, int perm) {
-  return _real_mkdir(path.Join().c_str(), perm);
+  std::string path_str = path.Join();
+  return _real_mkdir(path_str.c_str(), perm);
 }
 
 Error PassthroughFs::Rmdir(const Path& path) {
-  return _real_rmdir(path.Join().c_str());
+  std::string path_str = path.Join();
+  return _real_rmdir(path_str.c_str());
 }
 
 Error PassthroughFs::Remove(const Path& path) {
   // Not implemented by NaCl.
   return ENOSYS;
 }
 
 Error PassthroughFs::Rename(const Path& path, const Path& newpath) {
   // Not implemented by NaCl.
   return ENOSYS;
 }
 
 }  // namespace nacl_io