On 08.11.2016 00:54, Michael Niedermayer wrote:
> On Mon, Nov 07, 2016 at 11:49:52PM +0100, Andreas Cadhalpun wrote:
>> Signed-off-by: Andreas Cadhalpun <andreas.cadhal...@googlemail.com>
>> ---
>> libavformat/mpegts.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
>> index fad10c6..77d63f2 100644
>> --- a/libavformat/mpegts.c
>> +++ b/libavformat/mpegts.c
>> @@ -2692,6 +2692,10 @@ static int mpegts_read_header(AVFormatContext *s)
>> /* NOTE1: the bitrate is computed without the FEC */
>> /* NOTE2: it is only the bitrate of the start of the stream */
>> ts->pcr_incr = (pcrs[1] - pcrs[0]) / (packet_count[1] -
>> packet_count[0]);
>> + if (ts->pcr_incr <= 0) {
>> + av_log(s, AV_LOG_ERROR, "invalid pcr increment %d\n",
>> ts->pcr_incr);
>> + return AVERROR_INVALIDDATA;
>> + }
>
> if a pcr pair is bad i would suggest to run the loop by another
> iteration
That's a good idea. New patch attached.
Best regards,
Andreas
>From 9d7a34dbdd9a5b97c9b51c47f918df7237b42fa6 Mon Sep 17 00:00:00 2001
From: Andreas Cadhalpun <andreas.cadhal...@googlemail.com>
Date: Mon, 7 Nov 2016 23:37:59 +0100
Subject: [PATCH] mpegts: prevent division by zero
Signed-off-by: Andreas Cadhalpun <andreas.cadhal...@googlemail.com>
---
libavformat/mpegts.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
index fad10c6..048073b 100644
--- a/libavformat/mpegts.c
+++ b/libavformat/mpegts.c
@@ -2681,8 +2681,16 @@ static int mpegts_read_header(AVFormatContext *s)
packet_count[nb_pcrs] = nb_packets;
pcrs[nb_pcrs] = pcr_h * 300 + pcr_l;
nb_pcrs++;
- if (nb_pcrs >= 2)
- break;
+ if (nb_pcrs >= 2) {
+ if (pcrs[1] - pcrs[0] > 0) {
+ /* the difference needs to be positive to make sense for bitrate computation */
+ break;
+ } else {
+ pcrs[0] = pcrs[1];
+ packet_count[0] = packet_count[1];
+ nb_pcrs--;
+ }
+ }
} else {
finished_reading_packet(s, ts->raw_packet_size);
}
--
2.10.2
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
