[FFmpeg-devel] [PATCH 4/5] avformat/mxfdec: Check index_edit_rate

[Michael Niedermayer]

Fixes: Assertion b >=0 failed at libavutil/mathematics.c:62
Fixes: 67811/clusterfuzz-testcase-minimized-ffmpeg_dem_MXF_fuzzer-5108429687422976

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavformat/mxfdec.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 04de4c1d5e3..233d614f783 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -1264,6 +1264,9 @@ static int mxf_read_index_table_segment(void *arg, AVIOContext *pb, int tag, int
     case 0x3F0B:
         segment->index_edit_rate.num = avio_rb32(pb);
         segment->index_edit_rate.den = avio_rb32(pb);
+        if (segment->index_edit_rate.num <= 0 ||
+            segment->index_edit_rate.den <= 0)
+            return AVERROR_INVALIDDATA;
         av_log(NULL, AV_LOG_TRACE, "IndexEditRate %d/%d\n", segment->index_edit_rate.num,
                 segment->index_edit_rate.den);
         break;
-- 
2.17.1