[FFmpeg-cvslog] avformat/utils: Discard huge timestamps which would cause overflows if used in basic computations

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sun Sep 25 22:21:53 2016 +0200| [e936c8d176efd1a0a41e22df24564b1178c79ea9] | committer: Michael Niedermayer

avformat/utils: Discard huge timestamps which would cause overflows if used in basic computations

Allowing larger timestamps makes it impossible to calculate basic things like the
difference of 2 timestamps or their sum without checking each individual computation for
overflow.
This should avoid a significant number of overflow checks

Fixes Ticket5136

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e936c8d176efd1a0a41e22df24564b1178c79ea9
---

 libavformat/utils.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/libavformat/utils.c b/libavformat/utils.c
index 70dbfa1..74eed47 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -833,6 +833,12 @@ int ff_read_packet(AVFormatContext *s, AVPacket *pkt)
             continue;
         }
 
+        if (   (pkt->dts != AV_NOPTS_VALUE && (pkt->dts <= INT64_MIN/2 || pkt->dts >= INT64_MAX/2))
+            || (pkt->pts != AV_NOPTS_VALUE && (pkt->pts <= INT64_MIN/2 || pkt->pts >= INT64_MAX/2))) {
+            av_log(s, AV_LOG_WARNING, "Ignoring huge timestamps %"PRId64" %"PRId64"\n", pkt->dts, pkt->pts);
+            pkt->dts = pkt->pts = AV_NOPTS_VALUE;
+        }
+
         st = s->streams[pkt->stream_index];
 
         if (update_wrap_reference(s, st, pkt->stream_index, pkt) && st->pts_wrap_behavior == AV_PTS_WRAP_SUB_OFFSET) {