From ea12590c8ecc1e3c4c7732e5adced21fb5feffa6 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 4 Mar 2021 19:21:35 +0100 Subject: [PATCH] avformat/cafdec: Do not build an index if all packets are the same Fixes: Timeout Fixes: 28214/clusterfuzz-testcase-minimized-ffmpeg_dem_CAF_fuzzer-6495999421579264 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavformat/cafdec.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/libavformat/cafdec.c b/libavformat/cafdec.c index d56187f71f..2a9299d777 100644 --- a/libavformat/cafdec.c +++ b/libavformat/cafdec.c @@ -204,15 +204,20 @@ static int read_pakt_chunk(AVFormatContext *s, int64_t size) st->nb_frames += avio_rb32(pb); /* priming frames */ st->nb_frames += avio_rb32(pb); /* remainder frames */ - st->duration = 0; - for (i = 0; i < num_packets; i++) { - if (avio_feof(pb)) - return AVERROR_INVALIDDATA; - ret = av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME); - if (ret < 0) - return ret; - pos += caf->bytes_per_packet ? caf->bytes_per_packet : ff_mp4_read_descr_len(pb); - st->duration += caf->frames_per_packet ? caf->frames_per_packet : ff_mp4_read_descr_len(pb); + if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) { + st->duration = caf->frames_per_packet * num_packets; + pos = caf-> bytes_per_packet * num_packets; + } else { + st->duration = 0; + for (i = 0; i < num_packets; i++) { + if (avio_feof(pb)) + return AVERROR_INVALIDDATA; + ret = av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME); + if (ret < 0) + return ret; + pos += caf->bytes_per_packet ? caf->bytes_per_packet : ff_mp4_read_descr_len(pb); + st->duration += caf->frames_per_packet ? caf->frames_per_packet : ff_mp4_read_descr_len(pb); + } } if (avio_tell(pb) - ccount > size) {