nsvdec: Fix use of uninitialized streams.

Fixes CVE-2011-3940 (Out of bounds read resulting in out of bounds write)

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2012-01-24 22:20:26 +01:00
parent 7988dd1b9a
commit 5c011706bc

View File

@ -606,12 +606,12 @@ null_chunk_retry:
}
/* map back streams to v,a */
if (s->streams[0])
if (s->nb_streams > 0)
st[s->streams[0]->id] = s->streams[0];
if (s->streams[1])
if (s->nb_streams > 1)
st[s->streams[1]->id] = s->streams[1];
if (vsize/* && st[NSV_ST_VIDEO]*/) {
if (vsize && st[NSV_ST_VIDEO]) {
nst = st[NSV_ST_VIDEO]->priv_data;
pkt = &nsv->ahead[NSV_ST_VIDEO];
av_get_packet(pb, pkt, vsize);
@ -624,7 +624,7 @@ null_chunk_retry:
if(st[NSV_ST_VIDEO])
((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;
if (asize/*st[NSV_ST_AUDIO]*/) {
if (asize && st[NSV_ST_AUDIO]) {
nst = st[NSV_ST_AUDIO]->priv_data;
pkt = &nsv->ahead[NSV_ST_AUDIO];
/* read raw audio specific header on the first audio chunk... */