avcodec/cdtoons: Check sprite_offset is within the packet

Fixes: out of array read
Fixes: 20659/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CDTOONS_fuzzer-5754518731227136

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-05-11 21:08:17 +02:00
parent 19738b1bc2
commit 4d701e9222

View File

@ -190,6 +190,9 @@ static int cdtoons_decode_frame(AVCodecContext *avctx, void *data,
palette_set = bytestream_get_byte(&buf);
buf += 5;
if (sprite_offset > buf_size)
return AVERROR_INVALIDDATA;
/* read new sprites introduced in this frame */
buf = avpkt->data + sprite_offset;
while (sprite_count--) {