From patchwork Wed Jul 24 21:35:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 14063 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 885F344A09C for ; Thu, 25 Jul 2019 00:37:07 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 5A5756805A9; Thu, 25 Jul 2019 00:37:07 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe07-2.mx.upcmail.net (vie01a-dmta-pe07-2.mx.upcmail.net [84.116.36.18]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 0AE7C680550 for ; Thu, 25 Jul 2019 00:37:01 +0300 (EEST) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe07.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1hqOwW-0000SL-1Y for ffmpeg-devel@ffmpeg.org; Wed, 24 Jul 2019 23:37:00 +0200 Received: from localhost ([213.47.41.20]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id qOvXh6htd5D5NqOvXhN6uV; Wed, 24 Jul 2019 23:36:00 +0200 X-Env-Mailfrom: michael@niedermayer.cc X-Env-Rcptto: ffmpeg-devel@ffmpeg.org X-SourceIP: 213.47.41.20 X-CNFS-Analysis: v=2.3 cv=bu8y+3Si c=1 sm=1 tr=0 a=I1eytVlZLDX1BM2VTtTtSw==:117 a=I1eytVlZLDX1BM2VTtTtSw==:17 a=MKtGQD3n3ToA:10 a=1oJP67jkp3AA:10 a=GEAsPZ9sns4A:10 a=ZZnuYtJkoWoA:10 a=nZOtpAppAAAA:20 a=3-rihYAO-r2V47aNuYAA:9 a=1fhp2MxaeJtTNGEnv6mo:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=jd6J4Gguk5HxikPWLKER:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Wed, 24 Jul 2019 23:35:37 +0200 Message-Id: <20190724213538.29475-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 X-CMAE-Envelope: MS4wfEpQrUI61PFrEkvANSGvUc8tBSngKwwxvVsC02yJCcsGIoyEbeBJZAXt0u8vibd/pKz8SuolvYPSndlVpLS6zMyb5MNr9mufjFxyJVihj8dbe1F8SJkV PuY1By86jS+9tIGKUVa30w0lo45z//i6BAAhiuNzRTn0xdIwVTgHgUBS Subject: [FFmpeg-devel] [PATCH 1/2] avcodec/assdec: undefined use of memcpy() 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 Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Fixes: null pointer passed as argument 2, which is declared to never be null Fixes: 16008/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SSA_fuzzer-5650582821404672 (this is a separate issue found in this testcase) Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/assdec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavcodec/assdec.c b/libavcodec/assdec.c index 3178f2953c..f0b1069cd2 100644 --- a/libavcodec/assdec.c +++ b/libavcodec/assdec.c @@ -31,7 +31,8 @@ static av_cold int ass_decode_init(AVCodecContext *avctx) avctx->subtitle_header = av_malloc(avctx->extradata_size + 1); if (!avctx->subtitle_header) return AVERROR(ENOMEM); - memcpy(avctx->subtitle_header, avctx->extradata, avctx->extradata_size); + if (avctx->extradata_size) + memcpy(avctx->subtitle_header, avctx->extradata, avctx->extradata_size); avctx->subtitle_header[avctx->extradata_size] = 0; avctx->subtitle_header_size = avctx->extradata_size; return 0;