[FFmpeg-cvslog] r22210 - trunk/libavcodec/flashsv.c

[fenrir]

Author: fenrir
Date: Thu Mar  4 20:10:44 2010
New Revision: 22210

Log:
Fixed buffer overread in flashsv decoder.

Modified:
   trunk/libavcodec/flashsv.c

Modified: trunk/libavcodec/flashsv.c
==============================================================================
--- trunk/libavcodec/flashsv.c	Thu Mar  4 16:08:54 2010	(r22209)
+++ trunk/libavcodec/flashsv.c	Thu Mar  4 20:10:44 2010	(r22210)
@@ -113,6 +113,8 @@ static int flashsv_decode_frame(AVCodecC
     /* no supplementary picture */
     if (buf_size == 0)
         return 0;
+    if (buf_size < 4)
+        return -1;
 
     init_get_bits(&gb, buf, buf_size * 8);
 
@@ -181,6 +183,11 @@ static int flashsv_decode_frame(AVCodecC
 
             /* get the size of the compressed zlib chunk */
             int size = get_bits(&gb, 16);
+            if (8 * size > get_bits_left(&gb)) {
+                avctx->release_buffer(avctx, &s->frame);
+                s->frame.data[0] = NULL;
+                return -1;
+            }
 
             if (size == 0) {
                 /* no change, don't do anything */