wmaprodec: check num_vec_coeffs for validity

Fixes CVE-2012-2789

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This commit is contained in:
Michael Niedermayer 2012-04-14 11:07:11 +02:00 committed by Anton Khirnov
parent 0af49a63c7
commit 99f392a584
1 changed files with 6 additions and 1 deletions

View File

@ -1174,7 +1174,12 @@ static int decode_subframe(WMAProDecodeCtx *s)
int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
for (i = 0; i < s->channels_for_cur_subframe; i++) {
int c = s->channel_indexes_for_cur_subframe[i];
s->channel[c].num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
if (num_vec_coeffs > WMAPRO_BLOCK_MAX_SIZE) {
av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
return AVERROR_INVALIDDATA;
}
s->channel[c].num_vec_coeffs = num_vec_coeffs;
}
} else {
for (i = 0; i < s->channels_for_cur_subframe; i++) {