From 762e18da3fe64dbe7d3091fddf99aeee164017cc Mon Sep 17 00:00:00 2001 From: James Almer Date: Sun, 17 Oct 2021 13:25:04 -0300 Subject: [PATCH] avcodec/h264_picture: don't assume Film Grain Params side data will be present If a decoding error happens before frame side data is allocated, this assert may be triggered. And since applying film grain is not enforced (we just warn it wasn't applied and move on), we can just do that in such scenarios. Fixes: Assertion failure Fixes: clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5528650032742400 Signed-off-by: James Almer --- libavcodec/h264_picture.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/libavcodec/h264_picture.c b/libavcodec/h264_picture.c index 66fd9bc4cb..adf8a32378 100644 --- a/libavcodec/h264_picture.c +++ b/libavcodec/h264_picture.c @@ -252,9 +252,11 @@ int ff_h264_field_end(H264Context *h, H264SliceContext *sl, int in_setup) "hardware accelerator failed to decode picture\n"); } else if (!in_setup && cur->needs_fg && (!FIELD_PICTURE(h) || !h->first_field)) { AVFrameSideData *sd = av_frame_get_side_data(cur->f, AV_FRAME_DATA_FILM_GRAIN_PARAMS); - av_assert0(sd); // always present if `cur->needs_fg` - err = ff_h274_apply_film_grain(cur->f_grain, cur->f, &h->h274db, - (AVFilmGrainParams *) sd->data); + + err = AVERROR_INVALIDDATA; + if (sd) // a decoding error may have happened before the side data could be allocated + err = ff_h274_apply_film_grain(cur->f_grain, cur->f, &h->h274db, + (AVFilmGrainParams *) sd->data); if (err < 0) { av_log(h->avctx, AV_LOG_WARNING, "Failed synthesizing film " "grain, ignoring: %s\n", av_err2str(err));