From patchwork Tue Jun 18 23:53:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 13606 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 1CDF2446C96 for ; Wed, 19 Jun 2019 02:54:52 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 03FB568A95D; Wed, 19 Jun 2019 02:54:52 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe06-2.mx.upcmail.net (vie01a-dmta-pe06-2.mx.upcmail.net [84.116.36.15]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id D8B30689F3F for ; Wed, 19 Jun 2019 02:54:44 +0300 (EEST) 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 1hdNw4-0002fR-1E for ffmpeg-devel@ffmpeg.org; Wed, 19 Jun 2019 01:54:44 +0200 Received: from localhost ([213.47.41.20]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id dNv6h3bAO5D5NdNv6hYzHx; Wed, 19 Jun 2019 01:53:44 +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=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=MKtGQD3n3ToA:10 a=1oJP67jkp3AA:10 a=GEAsPZ9sns4A:10 a=ZZnuYtJkoWoA:10 a=nZOtpAppAAAA:20 a=nEnhbsBZVl10K3g01EgA:9 a=1fhp2MxaeJtTNGEnv6mo:22 a=pHzHmUro8NiASowvMSCR:22 a=nt3jZW36AmriUCFCBwmW:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Wed, 19 Jun 2019 01:53:03 +0200 Message-Id: <20190618235303.8738-3-michael@niedermayer.cc> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190618235303.8738-1-michael@niedermayer.cc> References: <20190618235303.8738-1-michael@niedermayer.cc> MIME-Version: 1.0 X-CMAE-Envelope: MS4wfNrIWTp1OiZtgxzVLypAxxwHiuFYvZlalcfIJ7Z8HkV1hBhUhYrJHYgIII+2ZiZOrz0LZ8P44jzF+snOukdp6yGaTw9b2X+M4O2VJj0Gx35pUTAZAWxM xROwug0CooQrWNHUyYH7vyU6i2LR8SXO0ef8SzxNSEcxuwE6Y4XX30Ui Subject: [FFmpeg-devel] [PATCH 3/3] avcodec/alac: Check lpc_quant 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" lpc_quant of 0 produces undefined behavior, thus disallow this. If valid samples use this then such a sample would be quite usefull to confirm the correct&lossles handling of this. Fixes: libavcodec/alac.c:218:25: runtime error: shift exponent -1 is negative Fixes: 15273/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALAC_fuzzer-5656388535058432 Fixes: 15276/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALAC_fuzzer-5761238417539072 Fixes: 15315/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALAC_fuzzer-5767260766994432 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/alac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/alac.c b/libavcodec/alac.c index 2f44340661..c234d7153b 100644 --- a/libavcodec/alac.c +++ b/libavcodec/alac.c @@ -306,7 +306,7 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index, rice_history_mult[ch] = get_bits(&alac->gb, 3); lpc_order[ch] = get_bits(&alac->gb, 5); - if (lpc_order[ch] >= alac->max_samples_per_frame) + if (lpc_order[ch] >= alac->max_samples_per_frame || !lpc_quant[ch]) return AVERROR_INVALIDDATA; /* read the predictor table */