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

native_client_sdk/src/libraries/nacl_io/html5fs/html5_fs.cc

Index: native_client_sdk/src/libraries/nacl_io/html5fs/html5_fs.cc
diff --git a/native_client_sdk/src/libraries/nacl_io/html5fs/html5_fs.cc b/native_client_sdk/src/libraries/nacl_io/html5fs/html5_fs.cc
index bb6b9cc87ed4f451f860377ab4d25aa1816555b6..5acc69c6ed67fc88d6580c8581c0e07e350c0f52 100644
--- a/native_client_sdk/src/libraries/nacl_io/html5fs/html5_fs.cc
+++ b/native_client_sdk/src/libraries/nacl_io/html5fs/html5_fs.cc
@@ -45,9 +45,8 @@ ino_t Html5Fs::HashPath(const Path& path) {
 
   // Apply a running DJB2a to each part of the path
   for (size_t segment = 0; segment < path.Size(); segment++) {
-    const char *ptr = path.Part(segment).c_str();
-    size_t len = path.Part(segment).length();
-    hash = HashPathSegment(hash, ptr, len);
+    std::string part = path.Part(segment);
+    hash = HashPathSegment(hash, part.c_str(), part.length());
   }
   return hash;
 }
@@ -71,8 +70,9 @@ Error Html5Fs::OpenWithMode(const Path& path, int open_flags, mode_t mode,
   if (error)
     return error;
 
+  std::string full_path(GetFullPath(path).Join());
   PP_Resource fileref = file_ref_iface_->Create(
-      filesystem_resource_, GetFullPath(path).Join().c_str());
+      filesystem_resource_, full_path.c_str());
   if (!fileref)
     return ENOENT;
 
@@ -114,10 +114,10 @@ Error Html5Fs::Mkdir(const Path& path, int permissions) {
   if (path.IsRoot())
     return EEXIST;
 
+  std::string full_path(GetFullPath(path).Join());
   ScopedResource fileref_resource(
       ppapi(),
-      file_ref_iface_->Create(filesystem_resource_,
-                              GetFullPath(path).Join().c_str()));
+      file_ref_iface_->Create(filesystem_resource_, full_path.c_str()));
   if (!fileref_resource.pp_resource())
     return ENOENT;
 
@@ -142,10 +142,10 @@ Error Html5Fs::RemoveInternal(const Path& path, int remove_type) {
   if (error)
     return error;
 
+  std::string full_path(GetFullPath(path).Join());
   ScopedResource fileref_resource(
       ppapi(),
-      file_ref_iface_->Create(filesystem_resource_,
-                              GetFullPath(path).Join().c_str()));
+      file_ref_iface_->Create(filesystem_resource_, full_path.c_str()));
   if (!fileref_resource.pp_resource())
     return ENOENT;