[SCM] libav/wheezy-security: h264: reset data_partitioning if decoding the slice header for NAL_DPA fails

[siretart at users.alioth.debian.org]

The following commit has been merged in the wheezy-security branch:
commit 3ee26080d6b3e777992b4b4124e62e1bf0ac0a65
Author: Anton Khirnov <anton at khirnov.net>
Date:   Thu Nov 28 10:54:35 2013 +0100

    h264: reset data_partitioning if decoding the slice header for NAL_DPA fails
    
    If it was set before then we can end up trying to decode a slice without
    a valid slice header, which can lead to invalid memory access.
    
    Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
    CC:libav-stable at libav.org

diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index f021e59..886fc04 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -4013,8 +4013,13 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size){
             hx->intra_gb_ptr=
             hx->inter_gb_ptr= NULL;
 
-            if ((err = decode_slice_header(hx, h)) < 0)
+            if ((err = decode_slice_header(hx, h)) < 0) {
+                /* make sure data_partitioning is cleared if it was set
+                 * before, so we don't try decoding a slice without a valid
+                 * slice header later */
+                s->data_partitioning = 0;
                 break;
+            }
 
             hx->s.data_partitioning = 1;
 

-- 
Libav/FFmpeg packaging