From patchwork Sun Dec 8 21:31:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 16677 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 662864487C8 for ; Sun, 8 Dec 2019 23:34:28 +0200 (EET) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 5144668B464; Sun, 8 Dec 2019 23:34:28 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe02-1.mx.upcmail.net (vie01a-dmta-pe02-1.mx.upcmail.net [62.179.121.157]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 9DBED68B4B6 for ; Sun, 8 Dec 2019 23:34:20 +0200 (EET) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe02.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1ie4C4-00057M-1I for ffmpeg-devel@ffmpeg.org; Sun, 08 Dec 2019 22:34:20 +0100 Received: from localhost ([213.47.68.29]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id e4B5i75XPwlyse4B6i20rg; Sun, 08 Dec 2019 22:33:20 +0100 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=E5OzWpVl c=1 sm=1 tr=0 a=2hcxjKEKjp0CzLx6oWAm4g==:117 a=2hcxjKEKjp0CzLx6oWAm4g==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=MKtGQD3n3ToA:10 a=1oJP67jkp3AA:10 a=GEAsPZ9sns4A:10 a=ZZnuYtJkoWoA:10 a=nZOtpAppAAAA:20 a=FRo3RcPnaZbvLHVyjJgA:9 a=1fhp2MxaeJtTNGEnv6mo:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=UDnyf2zBuKT2w-IlGP_r:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Sun, 8 Dec 2019 22:31:18 +0100 Message-Id: <20191208213120.15190-3-michael@niedermayer.cc> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191208213120.15190-1-michael@niedermayer.cc> References: <20191208213120.15190-1-michael@niedermayer.cc> MIME-Version: 1.0 X-CMAE-Envelope: MS4wfPiIpYt2ehjE1+IJzfCk5wRFbLCGf9wwfpgxTK04rXp8VamYarBeK/oK6XD6URSb1TPnBXVAq2JLzSR27yqleEXNhzV8MyPj8C2soPa2i4Z3i3jFFb0e nmOzNnMHJNN+C3S6W1zdHlAGnPqNuNJAJLeAy0BiAivA9EjBorLh++DY Subject: [FFmpeg-devel] [PATCH 3/5] avcodec/vc1dec: Limit bits by the actual bitstream size 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 (350 ->19sec) Fixes: 19249/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1IMAGE_fuzzer-6566896438870016 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/vc1dec.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c index ac3198e4fd..f54da63f99 100644 --- a/libavcodec/vc1dec.c +++ b/libavcodec/vc1dec.c @@ -1026,7 +1026,7 @@ static int vc1_decode_frame(AVCodecContext *avctx, void *data, ff_mpeg_er_frame_start(s); - v->bits = buf_size * 8; + v->bits = FFMIN(buf_size * 8, s->gb.size_in_bits); v->end_mb_x = s->mb_width; if (v->field_mode) { s->current_picture.f->linesize[0] <<= 1; @@ -1100,8 +1100,10 @@ static int vc1_decode_frame(AVCodecContext *avctx, void *data, continue; } ff_vc1_decode_blocks(v); - if (i != n_slices) + if (i != n_slices) { s->gb = slices[i].gb; + v->bits = FFMIN(buf_size * 8, s->gb.size_in_bits); + } } if (v->field_mode) { v->second_field = 0;