From patchwork Thu May 7 10:38:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 19527 Return-Path: X-Original-To: patchwork@ffaux-bg.ffmpeg.org Delivered-To: patchwork@ffaux-bg.ffmpeg.org Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by ffaux.localdomain (Postfix) with ESMTP id 7653144BCEB for ; Thu, 7 May 2020 13:53:22 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 540CE689EE7; Thu, 7 May 2020 13:53:22 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe03-1.mx.upcmail.net (vie01a-dmta-pe03-1.mx.upcmail.net [62.179.121.160]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id ACBC3689923 for ; Thu, 7 May 2020 13:53:15 +0300 (EEST) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe03.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1jWdw7-0004aw-5X for ffmpeg-devel@ffmpeg.org; Thu, 07 May 2020 12:39:27 +0200 Received: from localhost ([213.47.68.29]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id Wdv8j1wQF6Jy6Wdv8jqxMM; Thu, 07 May 2020 12:38:26 +0200 X-Env-Mailfrom: michael@niedermayer.cc X-Env-Rcptto: ffmpeg-devel@ffmpeg.org X-SourceIP: 213.47.68.29 X-CNFS-Analysis: v=2.3 cv=GKl27dFK c=1 sm=1 tr=0 a=2hcxjKEKjp0CzLx6oWAm4g==:117 a=2hcxjKEKjp0CzLx6oWAm4g==:17 a=MKtGQD3n3ToA:10 a=1oJP67jkp3AA:10 a=GEAsPZ9sns4A:10 a=ZZnuYtJkoWoA:10 a=pGLkceISAAAA:8 a=-bgQf4IkW6UWDHa-KqkA:9 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Thu, 7 May 2020 12:38:26 +0200 Message-Id: <20200507103826.3278-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.17.1 X-CMAE-Envelope: MS4wfOqZFc0JJtJ/uRmfL485wHf8Ba25+hx3/Y32oLsn11IRv74EiDmZtNxuFf+KyV6LZtZ8cvVmTW2b/vTOWPakH6c+rAu2y082NZSdGlh3sDO+qSIsPez2 tNnFq7btjEsIZtTVaSBE2HxKSBD2Bfm+SAvlPz2+bhhqX28Qh+17tUmc Subject: [FFmpeg-devel] [PATCH] avformat/mpegts: Shuffle avio_seek X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches MIME-Version: 1.0 Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" This avoids accessing an old, no longer valid buffer. Fixes: out of array access Fixes: crash_audio-2020 Found-by: le wu Signed-off-by: Michael Niedermayer --- libavformat/mpegts.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c index 0833d62ea5..a065c61c40 100644 --- a/libavformat/mpegts.c +++ b/libavformat/mpegts.c @@ -2881,15 +2881,16 @@ static int mpegts_resync(AVFormatContext *s, int seekback, const uint8_t *curren AVIOContext *pb = s->pb; int c, i; uint64_t pos = avio_tell(pb); - - avio_seek(pb, -FFMIN(seekback, pos), SEEK_CUR); + int64_t back = FFMIN(seekback, pos); //Special case for files like 01c56b0dc1.ts if (current_packet[0] == 0x80 && current_packet[12] == 0x47) { - avio_seek(pb, 12, SEEK_CUR); + avio_seek(pb, 12 - back, SEEK_CUR); return 0; } + avio_seek(pb, -back, SEEK_CUR); + for (i = 0; i < ts->resync_size; i++) { c = avio_r8(pb); if (avio_feof(pb))