[FFmpeg-cvslog] avformat/mxfdec: Use 64bit in remainder

[Michael Niedermayer]

ffmpeg | branch: release/5.0 | Michael Niedermayer <michael at niedermayer.cc> | Sun Dec 25 22:02:13 2022 +0100| [a2d13b294c9efa4c91daddd55474e474608c500a] | committer: Michael Niedermayer

avformat/mxfdec: Use 64bit in remainder

Fixes: signed integer overflow: 48000 * 223587 cannot be represented in type 'int'
Fixes: 54513/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5817594836025344

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Tomas Härdin <git at haerdin.se>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 64a04fc165d453fe49906b228ac16385eda28564)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=a2d13b294c9efa4c91daddd55474e474608c500a
---

 libavformat/mxfdec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 6fa44351e6..605f3f57a8 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -3808,8 +3808,8 @@ static int64_t mxf_compute_sample_count(MXFContext *mxf, AVStream *st,
     if ((sample_rate.num / sample_rate.den) == 48000) {
         return av_rescale_q(edit_unit, sample_rate, track->edit_rate);
     } else {
-        int remainder = (sample_rate.num * time_base.num) %
-                        (time_base.den * sample_rate.den);
+        int64_t remainder = (sample_rate.num * (int64_t)  time_base.num) %
+                            (  time_base.den * (int64_t)sample_rate.den);
         if (remainder)
             av_log(mxf->fc, AV_LOG_WARNING,
                    "seeking detected on stream #%d with time base (%d/%d) and "