From 6dc6e1cce0ec0aadab27e8b3fd3fc87c93c3acd6 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer <michael@niedermayer.cc> Date: Thu, 4 Mar 2021 00:15:53 +0100 Subject: [PATCH] avformat/utils: Fix integer overflow with duration_gcd in ff_rfps_calculate() Fixes: signed integer overflow: 136323327 * 281474976710656 cannot be represented in type 'long' Fixes: 30913/clusterfuzz-testcase-minimized-ffmpeg_dem_IVF_fuzzer-5753392189931520 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavformat/utils.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index 88f6f18f1f..dffc259ed8 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -3409,7 +3409,8 @@ void ff_rfps_calculate(AVFormatContext *ic) // the check for tb_unreliable() is not completely correct, since this is not about handling // an unreliable/inexact time base, but a time base that is finer than necessary, as e.g. // ipmovie.c produces. - if (tb_unreliable(st->internal->avctx) && st->internal->info->duration_count > 15 && st->internal->info->duration_gcd > FFMAX(1, st->time_base.den/(500LL*st->time_base.num)) && !st->r_frame_rate.num) + if (tb_unreliable(st->internal->avctx) && st->internal->info->duration_count > 15 && st->internal->info->duration_gcd > FFMAX(1, st->time_base.den/(500LL*st->time_base.num)) && !st->r_frame_rate.num && + st->internal->info->duration_gcd < INT64_MAX / st->time_base.num) av_reduce(&st->r_frame_rate.num, &st->r_frame_rate.den, st->time_base.den, st->time_base.num * st->internal->info->duration_gcd, INT_MAX); if (st->internal->info->duration_count>1 && !st->r_frame_rate.num && tb_unreliable(st->internal->avctx)) {