avcodec/mpeg4videodec: Check for bitstream overread in decode_vol_header()

Fixes out of array read
Fixes: 08e48e9daae7d8f8ab6dbe3919e797e5-asan_heap-oob_157461c_5295_cov_1266798650_firefing.mpg
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2014-02-20 05:48:54 +01:00
parent 916a79227e
commit 3edc3b1595

View File

@ -1916,6 +1916,11 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
else
s->quarter_sample = 0;
if (get_bits_left(gb) < 4) {
av_log(s->avctx, AV_LOG_ERROR, "VOL Header truncated\n");
return AVERROR_INVALIDDATA;
}
if (!get_bits1(gb)) {
int pos = get_bits_count(gb);
int estimation_method = get_bits(gb, 2);