[FFmpeg-cvslog] avformat/concatdec: Check user_duration sum

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Tue Mar 26 00:16:39 2024 +0100| [dcfc13c199ab8385673ff91c8d81d3451a9bb415] | committer: Michael Niedermayer

avformat/concatdec: Check user_duration sum

Fixes: 62276/clusterfuzz-testcase-minimized-ffmpeg_dem_CONCAT_fuzzer-6434245599690752
Fixes: signed integer overflow: 9223372026773000000 + 22337000000 cannot be represented in type 'long'

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 007486058c2eb7a7518450a2ddb4fa98845887a3)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=dcfc13c199ab8385673ff91c8d81d3451a9bb415
---

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

diff --git a/libavformat/concatdec.c b/libavformat/concatdec.c
index 09839f2d15..41e66570fc 100644
--- a/libavformat/concatdec.c
+++ b/libavformat/concatdec.c
@@ -503,6 +503,8 @@ static int concat_read_header(AVFormatContext *avf)
             cat->files[i].user_duration = cat->files[i].outpoint - cat->files[i].inpoint;
         }
         cat->files[i].duration = cat->files[i].user_duration;
+        if (time + (uint64_t)cat->files[i].user_duration > INT64_MAX)
+            return AVERROR_INVALIDDATA;
         time += cat->files[i].user_duration;
     }
     if (i == cat->nb_files) {