[automerger] Fix OOB access in mpeg4/h263 decoder am: ef4ce15700 am: 9832a2a3f4

Change-Id: I94d3301f216945075838b6cc46e7644f8e91a313

media/libstagefright/codecs/m4v_h263/dec/src/vop.cpp

@@ -1355,6 +1355,14 @@ PV_STATUS DecodeShortHeader(VideoDecData *video, Vop *currVop)
             int tmpHeight = (tmpDisplayHeight + 15) & -16;
             int tmpWidth = (tmpDisplayWidth + 15) & -16;
 
+            if (tmpWidth > video->width)
+            {
+                // while allowed by the spec, this decoder does not actually
+                // support an increase in size.
+                ALOGE("width increase not supported");
+                status = PV_FAIL;
+                goto return_point;
+            }
             if (tmpHeight * tmpWidth > video->size)
             {
                 // This is just possibly "b/37079296".