[FFmpeg-cvslog] avformat/demux: Check packet duration

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Fri Aug 16 18:14:37 2024 +0200| [f7900a560983ce364eff2a5b9d6a54269999f717] | committer: Michael Niedermayer

avformat/demux: Check packet duration

Fixes: signed integer overflow: 24320 + 9223372036854775573 cannot be represented in type 'long'
Fixes: 71001/clusterfuzz-testcase-minimized-ffmpeg_dem_MATROSKA_fuzzer-5644785744936960

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=f7900a560983ce364eff2a5b9d6a54269999f717
---

 libavformat/demux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/demux.c b/libavformat/demux.c
index cba1f2e4df..d8ab29431e 100644
--- a/libavformat/demux.c
+++ b/libavformat/demux.c
@@ -2810,7 +2810,7 @@ int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
                     av_packet_unref(pkt1);
                 break;
             }
-            if (pkt->duration > 0) {
+            if (pkt->duration > 0 && pkt->duration < INT64_MAX - sti->info->codec_info_duration) {
                 const int fields = sti->codec_desc && (sti->codec_desc->props & AV_CODEC_PROP_FIELDS);
                 if (avctx->codec_type == AVMEDIA_TYPE_SUBTITLE && pkt->pts != AV_NOPTS_VALUE && st->start_time != AV_NOPTS_VALUE && pkt->pts >= st->start_time
                     && (uint64_t)pkt->pts - st->start_time < INT64_MAX