On 2021-12-21 02:18 am, Andreas Rheinhardt wrote:
Gyan Doshi:Avoids overreading the box and ingesting absurd values into stts_data --- libavformat/mov.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libavformat/mov.c b/libavformat/mov.c index 2aed6e80ef..5a7209837f 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -2935,6 +2935,11 @@ static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom) avio_rb24(pb); /* flags */ entries = avio_rb32(pb);+ if (atom.size < 8 + (int64_t)entries*8) {+ av_log(c->fc, AV_LOG_ERROR, "Truncated STTS box for st %d.\n", c->fc->nb_streams-1); + return AVERROR_INVALIDDATA; + } + av_log(c->fc, AV_LOG_TRACE, "track[%u].stts.entries = %u\n", c->fc->nb_streams-1, entries);This might fix the issue with the fuzzer sample Michael gave you, but what would stop the fuzzer (or a malicious adversary) from simply using a gigantic atom size?
Do you want the comparison to switch to a strict inequality? Regards, Gyan _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
