From 408c0c43d7c201a586f76040f2ffcfb28a71d9f1 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 15 Aug 2022 00:02:37 +0200 Subject: [PATCH] avcodec/h263dec: Sanity check against minimal I/P frame size Fixes: Timeout Fixes: 49718/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG4_fuzzer-4874987894341632 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit ca4ff9c21cb77e024fa4ff5889826a8bee4d0e0a) Signed-off-by: Michael Niedermayer --- libavcodec/h263dec.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c index 2682a7f43a..2d1752d76e 100644 --- a/libavcodec/h263dec.c +++ b/libavcodec/h263dec.c @@ -551,6 +551,8 @@ retry: avctx->has_b_frames = !s->low_delay; if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) { + if (s->pict_type != AV_PICTURE_TYPE_B && s->mb_num/2 > get_bits_left(&s->gb)) + return AVERROR_INVALIDDATA; if (ff_mpeg4_workaround_bugs(avctx) == 1) goto retry; if (s->studio_profile != (s->idsp.idct == NULL))