Fix for possible crashes due to pointer value being null

content/common/cursors/webcursor.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 "content/common/cursors/webcursor.h"
 
 #include "base/logging.h"
 #include "base/pickle.h"
 #include "third_party/WebKit/public/platform/WebImage.h"
 
@@ skipping 124 matching lines @@
 bool WebCursor::Serialize(Pickle* pickle) const {
   if (!pickle->WriteInt(type_) ||
       !pickle->WriteInt(hotspot_.x()) ||
       !pickle->WriteInt(hotspot_.y()) ||
       !pickle->WriteInt(custom_size_.width()) ||
       !pickle->WriteInt(custom_size_.height()) ||
       !pickle->WriteFloat(custom_scale_))
     return false;
 
   const char* data = NULL;
-  if (!custom_data_.empty())
-    data = &custom_data_[0];
+  if (custom_data_.empty())
+    return false;

[Charlie Reis, 2015/02/17 21:26:59]

This is probably the wrong thing to do.  It's probably legitimate to have an
empty custom_data_, in which case we would write 0 bytes and move on
successfully.  There's no reason to abort early here with a return false.

Are you sure there's even a bug here?  Writing 0 bytes may mean that we don't
touch |data| at all, so it might not matter that it's NULL.  (In fact, it looks
like WriteData may put that 0 into the format, so it matters that we make that
call.)

[Sunil Ratnu, 2015/02/18 09:04:45]

Removed this change as we do not need to abort early.

+
+  data = &custom_data_[0];
   if (!pickle->WriteData(data, custom_data_.size()))
     return false;
 
   return SerializePlatformData(pickle);
 }
 
 bool WebCursor::IsCustom() const {
   return type_ == WebCursorInfo::TypeCustom;
 }
 
@@ skipping 96 matching lines @@
     return;
 
   // Clamp the hotspot to the custom image's dimensions.
   hotspot_.set_x(std::max(0,
                           std::min(custom_size_.width() - 1, hotspot_.x())));
   hotspot_.set_y(std::max(0,
                           std::min(custom_size_.height() - 1, hotspot_.y())));
 }
 
 }  // namespace content