From 97fe9123d107fcb833bac4ebd2936557ccccd8eb Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 11 May 2021 18:40:32 +0200 Subject: [PATCH] avformat/matroskadec: Fix handling of huge default durations Fixes: negation of -9223372036854775808 cannot be represented in type 'int64_t' (aka 'long'); cast to an unsigned type to negate this value to itself Fixes: 33997/clusterfuzz-testcase-minimized-ffmpeg_dem_WEBM_DASH_MANIFEST_fuzzer-6752039691485184 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 343d950a4a8a8c32f5f7d9d4ac1fbe317cb9cc80) Signed-off-by: Michael Niedermayer --- libavformat/matroskadec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c index f8c44a8f2c..4492e76e82 100644 --- a/libavformat/matroskadec.c +++ b/libavformat/matroskadec.c @@ -2042,8 +2042,9 @@ static int matroska_parse_tracks(AVFormatContext *s) st->need_parsing = AVSTREAM_PARSE_HEADERS; if (track->default_duration) { + int div = track->default_duration <= INT64_MAX ? 1 : 2; av_reduce(&st->avg_frame_rate.num, &st->avg_frame_rate.den, - 1000000000, track->default_duration, 30000); + 1000000000 / div, track->default_duration / div, 30000); #if FF_API_R_FRAME_RATE if ( st->avg_frame_rate.num < st->avg_frame_rate.den * 1000LL && st->avg_frame_rate.num > st->avg_frame_rate.den * 5LL)