From a31e9f68a426f634e002282885c6c2eb1bfbea44 Mon Sep 17 00:00:00 2001 From: Mans Rullgard Date: Sat, 8 Oct 2011 02:06:26 +0100 Subject: [PATCH] lavf: fix signed overflow in avformat_find_stream_info() On the first iteration through this code, last_dts is always INT64_MIN (AV_NOPTS_VALUE) and the subtraction overflows in an invalid manner. Although the result is only used if the input values are valid, performing the subtraction is still not allowed in a strict environment. Signed-off-by: Mans Rullgard --- libavformat/utils.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index 0ba6fc3cd9..e4e6d24e53 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -2358,9 +2358,9 @@ int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options) } { int64_t last = st->info->last_dts; - int64_t duration= pkt->dts - last; - if(pkt->dts != AV_NOPTS_VALUE && last != AV_NOPTS_VALUE && duration>0){ + if(pkt->dts != AV_NOPTS_VALUE && last != AV_NOPTS_VALUE && pkt->dts > last){ + int64_t duration= pkt->dts - last; double dur= duration * av_q2d(st->time_base); // if(st->codec->codec_type == AVMEDIA_TYPE_VIDEO)