[FFmpeg-devel] [PATCH 3/4] avformat/sbgdec: Check for overflow in timestamp preparation

[Michael Niedermayer]

Fixes: signed integer overflow: 9223372036854775807 + 86400000000 cannot be represented in type 'long'
Fixes: 29102/clusterfuzz-testcase-minimized-ffmpeg_dem_SBG_fuzzer-6731040263634944

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/sbgdec.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavformat/sbgdec.c b/libavformat/sbgdec.c
index 83016d0c13..9530ea42a5 100644
--- a/libavformat/sbgdec.c
+++ b/libavformat/sbgdec.c
@@ -1291,6 +1291,10 @@ static int generate_intervals(void *log, struct sbg_script *s, int sample_rate,
         ev1 = &s->events[i];
         ev2 = &s->events[(i + 1) % s->nb_events];
         ev1->ts_int   = ev1->ts;
+
+        if (!ev1->fade.slide && ev1 >= ev2 && ev2->ts > INT64_MAX - period)
+            return AVERROR_INVALIDDATA;
+
         ev1->ts_trans = ev1->fade.slide ? ev1->ts
                                         : ev2->ts + (ev1 < ev2 ? 0 : period);
     }
-- 
2.17.1