avcodec/mpeg4videodec: Check available data before reading custom matrix

Fixes: out of array read
Fixes: 76c515fc3779d1b838667c61ea13ce92/asan_heap-oob_1fc0d07_8913_794a4629a264ebdb25b58d3a94ed1785.bit

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 891dc8f87536ac2ec695c70d081345224524ad99)

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2015-11-29 23:44:40 +01:00
parent 88ccca204a
commit fc69fa8474

View File

@ -1875,6 +1875,10 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
int last = 0;
for (i = 0; i < 64; i++) {
int j;
if (get_bits_left(gb) < 8) {
av_log(s->avctx, AV_LOG_ERROR, "insufficient data for custom matrix\n");
return AVERROR_INVALIDDATA;
}
v = get_bits(gb, 8);
if (v == 0)
break;
@ -1898,6 +1902,10 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
int last = 0;
for (i = 0; i < 64; i++) {
int j;
if (get_bits_left(gb) < 8) {
av_log(s->avctx, AV_LOG_ERROR, "insufficient data for custom matrix\n");
return AVERROR_INVALIDDATA;
}
v = get_bits(gb, 8);
if (v == 0)
break;