[FFmpeg-cvslog] avformat/moflex: Check pkt_size

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sun Oct 25 00:23:07 2020 +0200| [40348637bee613a9123d869acd7be0ce837653ad] | committer: Michael Niedermayer

avformat/moflex: Check pkt_size

Fixes: Timeout (>20sec -> 1ms)
Fixes: 26527/clusterfuzz-testcase-minimized-ffmpeg_dem_MOFLEX_fuzzer-6308307310215168

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=40348637bee613a9123d869acd7be0ce837653ad
---

 libavformat/moflex.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavformat/moflex.c b/libavformat/moflex.c
index a24e12eb8e..8142925adc 100644
--- a/libavformat/moflex.c
+++ b/libavformat/moflex.c
@@ -316,6 +316,8 @@ static int moflex_read_packet(AVFormatContext *s, AVPacket *pkt)
             }
 
             pkt_size = pop_int(br, pb, 13) + 1;
+            if (pkt_size > m->size)
+                return AVERROR_INVALIDDATA;
             packet   = s->streams[stream_index]->priv_data;
             if (!packet) {
                 avio_skip(pb, pkt_size);