commit 2bcd3136b3239b4a620fa13205b2892bf0a03081
author Michael Niedermayer <michael@niedermayer.cc> Thu Apr 04 00:38:20 2024 +0200
committer Michael Niedermayer <michael@niedermayer.cc> Thu Apr 04 21:10:57 2024 +0200
tree db9126f57dea19b4ed375aede24b4be412a36368
parent c657698796c136866d7358bf75c68b07f1668f22

avformat/mxfdec: Check index_edit_rate

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@niedermayer.cc>
(cherry picked from commit ed49391961999f028e0bc55767d0eef6eeb15e49)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/mxfdec.c

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index f2bdf70..a239694 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -938,6 +938,9 @@
     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;