On 1/30/20 3:28 PM, Alfred E. Heggestad wrote: > this usecase will cause a division by zero trap: > > 1. dashenc has received one frame > 2. os->max_pts and os->start_pts have same value > 3. delta between max_pts and start_pts is 0 > 4. av_rescale_q(0, x, y) returns 0 > 5. this value is used as denominator in division > 6. Bang! -> segfault > > this fix checks that max_pts > start_pts. > the fix has been tested and works. > > please review and suggest better fixes. > > Signed-off-by: Alfred E. Heggestad <alfred.hegges...@gmail.com> > --- > libavformat/dashenc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c > index f555f208a7..3b651b9514 100644 > --- a/libavformat/dashenc.c > +++ b/libavformat/dashenc.c > @@ -1883,7 +1883,7 @@ static int dash_flush(AVFormatContext *s, int > final, int stream) > > st->time_base, > > AV_TIME_BASE_Q)); > > - if (!os->muxer_overhead) > + if (!os->muxer_overhead && os->max_pts > os->start_pts) > os->muxer_overhead = ((int64_t) (range_length - > os->total_pkt_size) * > 8 * AV_TIME_BASE) / > av_rescale_q(os->max_pts - os->start_pts, LGTM.
This actually exposes a corner case bug in overhead calculation logic. Guess we will need to come up with a better logic for it. Until then, this fix will atleast make sure things don’t crash. Thanks, Karthick _______________________________________________ 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".
