From patchwork Thu Dec 26 00:18:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 16957 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 5A1C344A666 for ; Thu, 26 Dec 2019 02:27:17 +0200 (EET) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 371D06802B9; Thu, 26 Dec 2019 02:27:17 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe05-2.mx.upcmail.net (vie01a-dmta-pe05-2.mx.upcmail.net [84.116.36.12]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 457D36800A9 for ; Thu, 26 Dec 2019 02:27:10 +0200 (EET) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe05.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1ikGu9-0002CP-0O for ffmpeg-devel@ffmpeg.org; Thu, 26 Dec 2019 01:21:29 +0100 Received: from localhost ([213.47.68.29]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id kGtAiZHXZwlyskGtAiPcfX; Thu, 26 Dec 2019 01:20:29 +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=MKtGQD3n3ToA:10 a=1oJP67jkp3AA:10 a=GEAsPZ9sns4A:10 a=ZZnuYtJkoWoA:10 a=nZOtpAppAAAA:20 a=ulWE8gZB9U7qkde59wsA:9 a=1fhp2MxaeJtTNGEnv6mo:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=SsAZrZ5W_gNWK9tOzrEV:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Thu, 26 Dec 2019 01:18:08 +0100 Message-Id: <20191226001809.28204-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 X-CMAE-Envelope: MS4wfJ1xBmKyNb06pf4/MqS0ZuifUroW8xZin7APKgQpaHLttdKIKsWdgKuLXRE5uNAQMTTWYsv5yj3x12cBZQJdMqiT4XixApFlAoK950kRj0G24MPs3/Jy Y0BK0uA1mGrlCgb/oU+tIYEDMttfyub7raLoKENo3XYMi3JsP/1aFSBW Subject: [FFmpeg-devel] [PATCH 1/2] avcodec/mpeg12dec: Fix invalid shift in mpeg2_fast_decode_block_intra() 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: left shift of negative value -695 Fixes: 19232/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG1VIDEO_fuzzer-5702856963522560 Fixes: 19555/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG1VIDEO_fuzzer-5741218147598336 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/mpeg12dec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c index 775579f9f0..4643992d28 100644 --- a/libavcodec/mpeg12dec.c +++ b/libavcodec/mpeg12dec.c @@ -586,7 +586,7 @@ static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, dc = s->last_dc[component]; dc += diff; s->last_dc[component] = dc; - block[0] = dc << (3 - s->intra_dc_precision); + block[0] = dc * (1 << (3 - s->intra_dc_precision)); i = 0; if (s->intra_vlc_format) rl = &ff_rl_mpeg2;