Reject vp8 video having alpha and image planes of different sizes.

media/filters/vpx_video_decoder.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 "media/filters/vpx_video_decoder.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 414 matching lines @@
       if (!vpx_image_alpha) {
         *video_frame = NULL;
         return true;
       }
 
       if (vpx_image_alpha->user_priv !=
           reinterpret_cast<void*>(&timestamp_alpha)) {
         LOG(ERROR) << "Invalid output timestamp on alpha.";
         return false;
       }
+
+      if (vpx_image_alpha->d_h != vpx_image->d_h ||
+          vpx_image_alpha->d_w != vpx_image->d_w) {
+        LOG(ERROR) << "The alpha plane dimensions are not the same as the "
+                      "image dimensions.";
+        return false;
+      }
     }
   }
 
   CopyVpxImageTo(vpx_image, vpx_image_alpha, video_frame);
   (*video_frame)->set_timestamp(base::TimeDelta::FromMicroseconds(timestamp));
   return true;
 }
 
 void VpxVideoDecoder::CopyVpxImageTo(const vpx_image* vpx_image,
                                      const struct vpx_image* vpx_image_alpha,
@@ skipping 51 matching lines @@
              uv_rows,
              video_frame->get());
   if (!vpx_codec_alpha_)
     return;
   if (!vpx_image_alpha) {
     MakeOpaqueAPlane(
         vpx_image->stride[VPX_PLANE_Y], vpx_image->d_h, video_frame->get());
     return;
   }
   CopyAPlane(vpx_image_alpha->planes[VPX_PLANE_Y],
-             vpx_image->stride[VPX_PLANE_Y],
-             vpx_image->d_h,
+             vpx_image_alpha->stride[VPX_PLANE_Y],
+             vpx_image_alpha->d_h,
              video_frame->get());
 }
 
 }  // namespace media