From patchwork Fri May 28 18:48:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 27973 Delivered-To: ffmpegpatchwork2@gmail.com Received: by 2002:a6b:b214:0:0:0:0:0 with SMTP id b20csp800959iof; Fri, 28 May 2021 11:55:01 -0700 (PDT) X-Google-Smtp-Source: ABdhPJy9WXI+iQM1QcnQLTHa8192XHYRQkMVeqsIVEYid+Gxs28Ua2N9HpWzixJzUTkslzqCE1Lo X-Received: by 2002:a17:906:33d3:: with SMTP id w19mr10666847eja.399.1622228101551; Fri, 28 May 2021 11:55:01 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1622228101; cv=none; d=google.com; s=arc-20160816; b=tlD8xaYYrPE60j8hDjdn4zTdnnioJD5uY3lI9vyNeHWsEYUkqmITGI3mSOhj3hAgeI KkplcwfNH329XwVZLyPweyHI3o4pleB2tgtjJQg5HMt2qXQEHiRkghkDiiEQnpEtCGeI V4C/mERC5tlhGFZ3+wOUFGoRUmf0PUfkkOaPxBoi4uEQpOqAgj2ewWmQA7/TwAFGCB5V hrJWCWYQmNo3uWgg94Y8u1VSVxOww2fPtZ6P8NjDvdXzSEhO8XZ5PESQwReNWsJZtec5 MXki9hQLaZF4Ix02kfX5MNZSkvDI/vvNr4zAWB/kXNZd/umMAOAhDrFa37BzhY4WRPVE ehpA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:mime-version:reply-to :list-subscribe:list-help:list-post:list-archive:list-unsubscribe :list-id:precedence:subject:references:in-reply-to:message-id:date :to:from:delivered-to; bh=NEJ7+7fT21KGyhPI90xx3QPCMsMn+8lMFq/lCDxrmLA=; b=N+uIFGyOCifx0oq2ywJPa+LRBWZS/YKe742LtHJcfAH31CfQAWr1rObN1AGXt9oxaW fuVlSxKO5sErkPZ0SdrqsJxwiPUbYtuVIhyKcg7QBJaKLmsp63V5iBG5xbZ6g/h8aBKw jIqaT/Uwt4anUEZG0jRtI57xlNloN7Ibjima2Ajz3WlisvWdXCsY4rLQmcQ/phhhnmFC w5QZt03h0JuPp6sTALP3bxyQcZ5b2luhW1o6LnCGZt//Rs2p9WTzwB0l7MpEypvOPQVJ 0FTDEaiqTwR3juZtATF7imOmtt/Uqb92b3SsszbjsW08FheZSaglorBqT4hYJVNVHizy 0i/g== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org. [79.124.17.100]) by mx.google.com with ESMTP id k22si6495397ejc.431.2021.05.28.11.55.00; Fri, 28 May 2021 11:55:01 -0700 (PDT) Received-SPF: pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) client-ip=79.124.17.100; Authentication-Results: mx.google.com; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 14B35680A9A; Fri, 28 May 2021 21:54:57 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe03-2.mx.upcmail.net (vie01a-dmta-pe03-2.mx.upcmail.net [62.179.121.161]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 600BE680263 for ; Fri, 28 May 2021 21:54:50 +0300 (EEST) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe03.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1lmhY6-002Re4-0E for ffmpeg-devel@ffmpeg.org; Fri, 28 May 2021 20:49:34 +0200 Received: from localhost ([213.47.68.29]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id mhX8lu3IfljeHmhX8lG58j; Fri, 28 May 2021 20:48:34 +0200 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=BoHjPrf5 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=ec5QTXoHaDwdn2ZpwYYA:9 a=pHzHmUro8NiASowvMSCR:22 a=Ew2E2A-JSTLzCXPT_086:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Fri, 28 May 2021 20:48:34 +0200 Message-Id: <20210528184834.4625-3-michael@niedermayer.cc> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210528184834.4625-1-michael@niedermayer.cc> References: <20210528184834.4625-1-michael@niedermayer.cc> X-CMAE-Envelope: MS4wfObS33MfqG/b3i3t+K5zYvuYNK7i9O78riDpUcCtmgmQ5HujqFEXAJj396Mi4bwtgLaXAinN4DVjD7T6m8zbFLFioG+Nd91PKdEEzr61zxzELMSjASd1 /isV3hm9H100qOFNT8ZejzhBCkGfpul9KBBR1DDCaNo1qEZMPmk8Suov Subject: [FFmpeg-devel] [PATCH 3/3] avcodec/lpc: Avoid floating point division by 0 in compute_ref_coefs() X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 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" X-TUID: VR/cMTbKurWM Fixes: Ticket7996 Fixes: CVE-2020-20445 Signed-off-by: Michael Niedermayer --- libavcodec/lpc.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/lpc.h b/libavcodec/lpc.h index 88ca247f87..52170fd623 100644 --- a/libavcodec/lpc.h +++ b/libavcodec/lpc.h @@ -143,7 +143,7 @@ static inline void compute_ref_coefs(const LPC_TYPE *autoc, int max_order, gen0[i] = gen1[i] = autoc[i + 1]; err = autoc[0]; - ref[0] = -gen1[0] / err; + ref[0] = -gen1[0] / ((USE_FIXED || err) ? err : 1); err += gen1[0] * ref[0]; if (error) error[0] = err; @@ -152,7 +152,7 @@ static inline void compute_ref_coefs(const LPC_TYPE *autoc, int max_order, gen1[j] = gen1[j + 1] + ref[i - 1] * gen0[j]; gen0[j] = gen1[j + 1] * ref[i - 1] + gen0[j]; } - ref[i] = -gen1[0] / err; + ref[i] = -gen1[0] / ((USE_FIXED || err) ? err : 1); err += gen1[0] * ref[i]; if (error) error[i] = err;