dv: Fix small stack overread related to CVE-2011-3929 and CVE-2011-3936.

Found with asan.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Alex Converse <alex.converse@gmail.com>
This commit is contained in:
Alex Converse 2012-01-26 15:08:26 -08:00
parent 5a396bb3a6
commit 2d1c0dea5f

View File

@ -127,10 +127,14 @@ static int dv_extract_audio(uint8_t* frame, uint8_t* ppcm[4],
/* We work with 720p frames split in half, thus even frames have
* channels 0,1 and odd 2,3. */
ipcm = (sys->height == 720 && !(frame[1] & 0x0C)) ? 2 : 0;
pcm = ppcm[ipcm++];
/* for each DIF channel */
for (chan = 0; chan < sys->n_difchan; chan++) {
/* next stereo channel (50Mbps and 100Mbps only) */
pcm = ppcm[ipcm++];
if (!pcm)
break;
/* for each DIF segment */
for (i = 0; i < sys->difseg_size; i++) {
frame += 6 * 80; /* skip DIF segment header */
@ -178,11 +182,6 @@ static int dv_extract_audio(uint8_t* frame, uint8_t* ppcm[4],
frame += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
}
}
/* next stereo channel (50Mbps and 100Mbps only) */
pcm = ppcm[ipcm++];
if (!pcm)
break;
}
return size;