avformat/subtitles: Check pts difference before use

Fixes: signed integer overflow: 0 - -9223372036854775808 cannot be represented in type 'long'
Fixes: 29102/clusterfuzz-testcase-minimized-ffmpeg_dem_MPL2_fuzzer-6747053545881600

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2021-04-25 19:49:14 +02:00
parent 8ef25d1182
commit e7a990164f

View File

@ -206,7 +206,7 @@ void ff_subtitles_queue_finalize(void *log_ctx, FFDemuxSubtitlesQueue *q)
q->sort == SUB_SORT_TS_POS ? cmp_pkt_sub_ts_pos
: cmp_pkt_sub_pos_ts);
for (i = 0; i < q->nb_subs; i++)
if (q->subs[i]->duration < 0 && i < q->nb_subs - 1)
if (q->subs[i]->duration < 0 && i < q->nb_subs - 1 && q->subs[i + 1]->pts - (uint64_t)q->subs[i]->pts <= INT64_MAX)
q->subs[i]->duration = q->subs[i + 1]->pts - q->subs[i]->pts;
if (!q->keep_duplicates)