From patchwork Mon Mar 25 16:17:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 12441 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 DE9CA447462 for ; Mon, 25 Mar 2019 18:20:02 +0200 (EET) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id B2D68689DA0; Mon, 25 Mar 2019 18:20:02 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe08-1.mx.upcmail.net (vie01a-dmta-pe08-1.mx.upcmail.net [84.116.36.20]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id CAE4F680C7B for ; Mon, 25 Mar 2019 18:19:56 +0200 (EET) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe08.mx.upcmail.net with esmtp (Exim 4.91) (envelope-from ) id 1h8SKK-00011O-6a for ffmpeg-devel@ffmpeg.org; Mon, 25 Mar 2019 17:19:56 +0100 Received: from localhost ([213.47.41.20]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id 8SJHhvv4FxLwq8SJHhujFV; Mon, 25 Mar 2019 17:18:51 +0100 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=WaxylHpX 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=oFSWNXTRgjs4FQ3PHwcA:9 a=gSRoXdgmEZ5E3Sse:21 a=RzYcSWc0Kq1g9JBN:21 a=1fhp2MxaeJtTNGEnv6mo:22 a=pHzHmUro8NiASowvMSCR:22 a=Ew2E2A-JSTLzCXPT_086:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Mon, 25 Mar 2019 17:17:42 +0100 Message-Id: <20190325161742.23518-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 X-CMAE-Envelope: MS4wfHIXVTmqJTwKwr35lCIsPvENlwoT3+ZnS7LwVsKDyq22dYadWYBPR1gNvGKHiE0OnVrfkhm3l6kO12Jv/CZ9/0TkY4EHyxTxW+2cl0Az8P+iE3UoWEF6 lePz/rbLvZfErx4C0axFaUgO/99X8LnAaJt6rjQt5no9Z8Wnf/ZE41Dr Subject: [FFmpeg-devel] [PATCH] avcodec/cinepak: check the first slice against the input size before obtaining a frame 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: Timeout (16sec -> 0.5sec) Fixes: 13854/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CINEPAK_fuzzer-5641061185093632 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/cinepak.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/libavcodec/cinepak.c b/libavcodec/cinepak.c index 9b0077402f..18ec19f08d 100644 --- a/libavcodec/cinepak.c +++ b/libavcodec/cinepak.c @@ -319,6 +319,9 @@ static int cinepak_predecode_check (CinepakContext *s) { int num_strips; int encoded_buf_size; + int i; + const uint8_t *data = s->data; + const uint8_t *eod = s->data + s->size; num_strips = AV_RB16 (&s->data[8]); encoded_buf_size = AV_RB24(&s->data[1]); @@ -353,6 +356,17 @@ static int cinepak_predecode_check (CinepakContext *s) if (s->size < 10 + s->sega_film_skip_bytes + num_strips * 12) return AVERROR_INVALIDDATA; + data += 10 + s->sega_film_skip_bytes; + + for (i=0; i < FFMIN(num_strips, 1); i++) { + int strip_size = AV_RB24 (&data[1]); + if (strip_size < 12 || eod - data < strip_size - strip_size * (int64_t)s->avctx->discard_damaged_percentage / 100) + return AVERROR_INVALIDDATA; + if (eod - data < strip_size) + break; + data += strip_size; + } + return 0; }