From patchwork Tue Jan 28 19:32:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 17604 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 11EEC44A5FF for ; Tue, 28 Jan 2020 21:33:28 +0200 (EET) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id EE80268B458; Tue, 28 Jan 2020 21:33:27 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe06-3.mx.upcmail.net (vie01a-dmta-pe06-3.mx.upcmail.net [84.116.36.16]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id BBD0D68B1B0 for ; Tue, 28 Jan 2020 21:33:18 +0200 (EET) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe06.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1iwWbu-000A9U-0O for ffmpeg-devel@ffmpeg.org; Tue, 28 Jan 2020 20:33:18 +0100 Received: from localhost ([213.47.68.29]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id wWawi48NgwlyswWawiKVsV; Tue, 28 Jan 2020 20:32:18 +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=8KmaKDjClP6GT9ITd8UA:9 a=1fhp2MxaeJtTNGEnv6mo:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=SsAZrZ5W_gNWK9tOzrEV:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Tue, 28 Jan 2020 20:32:17 +0100 Message-Id: <20200128193217.30405-3-michael@niedermayer.cc> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200128193217.30405-1-michael@niedermayer.cc> References: <20200128193217.30405-1-michael@niedermayer.cc> X-CMAE-Envelope: MS4wfFVynQGamuyTXxkNONBUjl9YfjcfGphV8KBA7Ky0ppFMX1YBLVsE6LUM1H1/UhkJYz1o+1+fw0kom+fOKlJKJnZu2E3t7FcKC+ctkRF5QCnYIr4yWSJA 3Gna7UBkl4JWW0sWOz9LbjaHAIB3LsVD0ziyfA/ffhlA3beCDqoduQri Subject: [FFmpeg-devel] [PATCH 3/3] avcodec/lagarith: Sanity check scale 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" A value of 24 and above can collaps the range to 0 which would not work. Fixes: Timeout (75sec -> 21sec) Fixes: 18707/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_LAGARITH_fuzzer-5708950892969984 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/lagarith.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavcodec/lagarith.c b/libavcodec/lagarith.c index 59169be5de..0a45812bc1 100644 --- a/libavcodec/lagarith.c +++ b/libavcodec/lagarith.c @@ -226,6 +226,9 @@ static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb) } } + if (scale_factor > 23) + return AVERROR_INVALIDDATA; + rac->scale = scale_factor; /* Fill probability array with cumulative probability for each symbol. */