From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-516909-1519834802-2-13374845561168746164 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519834801; b=kPmWDNu5spMQ6Ij+ZP3kOl5gMxamAwOt7NhVlXb2G6zAzPw /FgnU9WZMgTkmh0k8PZrlBWz3HqIHAnwCCS+INI42m3fSrcON9c6CFptxJiPcHk8 d3Oyy+eY59axzk6HcO1VMLbOx8A7rh/RQETPZXELUn64Z/z3L4ItP2JEJDGLlzM4 u/xY4ju1YeKyKhVg16mJhZ8xRM+icmou5ZfHuSv/pHiR9+9utSBxpsS1KtK59Rif Du1gmPqcPl36BOrOF1l8hxptYTs49qW1HQw6gsHmh6Ba2s691KVzO6nUYFvJW8lA jG6L7zRWSFKkLghbXL/+aLrMKsVJuynnntWVUqA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1519834801; bh=8LYD2TqJnDcsSJp22Rs 0EecBQCYaliTsKiUaJlFN9u8=; b=Z3qxuylLQryyLbDUaKkf8RksySiVNINItUC h8qiOdbaW4wtHKU75Ngibz8htDP9t6bKj2fjZcU3Gls5Stt3AZS3kuVNuFODByG5 V0y6QApCDe6WCuyE6wsooJAz9qdn8D3rhRMp+kKMWpbqdVcKj0kgC32kP7OrMWDU AuJg60GhXKZntvD91IjZ2nk3VBBjfRp+KKBCfO/XJQM4tfuyA54hVyt0F6sbjjsX V8NJ45orIvmtCcJe053kREUldqotYKVNxTP1SnvVwa38hzV/EDWSqVEZzGe1wjzh HBlXBrl/bR1p5I7uqpGZfDIjCX30WSol3PkPYn/o29pXAAVLtgw== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934711AbeB1QQI (ORCPT ); Wed, 28 Feb 2018 11:16:08 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35217 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934923AbeB1QQG (ORCPT ); Wed, 28 Feb 2018 11:16:06 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Takashi Iwai" , syzbot+7e6ee55011deeebce15d@syzkaller.appspotmail.com Date: Wed, 28 Feb 2018 15:20:18 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 201/254] ALSA: pcm: Remove yet superfluous WARN_ON() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.16.55-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai commit 23b19b7b50fe1867da8d431eea9cd3e4b6328c2c upstream. muldiv32() contains a snd_BUG_ON() (which is morphed as WARN_ON() with debug option) for checking the case of 0 / 0. This would be helpful if this happens only as a logical error; however, since the hw refine is performed with any data set provided by user, the inconsistent values that can trigger such a condition might be passed easily. Actually, syzbot caught this by passing some zero'ed old hw_params ioctl. So, having snd_BUG_ON() there is simply superfluous and rather harmful to give unnecessary confusions. Let's get rid of it. Reported-by: syzbot+7e6ee55011deeebce15d@syzkaller.appspotmail.com Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings --- sound/core/pcm_lib.c | 1 - 1 file changed, 1 deletion(-) --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -644,7 +644,6 @@ static inline unsigned int muldiv32(unsi { u_int64_t n = (u_int64_t) a * b; if (c == 0) { - snd_BUG_ON(!n); *r = 0; return UINT_MAX; }