From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3406733-1526426142-2-14592984059470425507 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no ("Email failed DMARC policy for domain") X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, MAILING_LIST_MULTI -1, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-IgnoreVacation: yes ("Email failed DMARC policy for domain") 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=fm2; t= 1526426142; b=QOX/97ZSqGe0qIrqjl/PW4iW+qqobjed4AwBFnhndq4DKL/umv EnuE9hVTpR6Qha9ny7KD5tYh/2ACvrjtJFbNJCBPsh15wOUH7D4PnW/DldMpDs6O HgunZkHcd9/Es5R2kG780QzaKrMmfGEDnbGR6DzSxhg9VNjv7onmldJXtcjNuSfH D/RkghVQw7aZYOFIVkUaX/P76Pq3zgepc+ErsZdv5xxwp71tYgrwPY8Fq+wCEvMf txmmS+PCV958wdpqfeFmjBDXJcxnxC28lqkmWIQpdiGc2lGFEV+s5i3DrTzLVK31 RVF9/8tHQ7O2bxey+oT8uQll6iOW20ryMCnQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=message-id:subject:from:to:cc:date :in-reply-to:references:content-type:mime-version :content-transfer-encoding:sender:list-id; s=fm2; t=1526426142; bh=g7HkmS0cJUvcuCu5zrSnaGnSE8qcgMlk4fSMiCznJ2A=; b=OVSg8onTYAK1 z0erlvCSwKCnDlfyTNaO7i1gjG5wnYMqGlxlf6xA+vWF3aAKNxjzeZ726Iej6F9H D843DrRmfZjfRcjFwFmx7IE26qqPAjIrulDolfMh+mBoPjOzL6Ygps95tcn6/VR3 5aU+zyt+knao5oHPjHqhunjXok1+tbH0I4GXaMnxunOzxTWcIIpRJKyuBNxNuDKe u+a2kZGXOO1W3Mxgb+IcDxgvNnoO+0OOSKqr44hIOMyHYI3ZHI6Wnhyy4X8xu2/2 a9C8Bj+PWUrPEDkuVfMsVGpSrFbRVL6NuuK5lDCF1Ig8N2w7K620JHMBlRSdDdsX /P4X3wp/kw== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=fail (p=none,has-list-id=yes,d=none) header.from=codethink.co.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-cm=none score=0; 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=codethink.co.uk header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=fail (p=none,has-list-id=yes,d=none) header.from=codethink.co.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-cm=none score=0; 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=codethink.co.uk header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfIx6NMVKfH7ycBKTRPHQDPQiV+vYy0qZEwTaP1AlASOApIgJGhywZDnlyAsg9Ck93eHCCpxrDq3rSYCJ4ezPqG/+Iruy2z/PF7hexlBsPbVOcTh8q0mx jm7jnqAgEBLAy2XlVZ9qJ4Q4BPG25afRSwPIgSmAkhwC6T7bseYknKV2ooK/cWRcLjS3bDl6HK/meogKZH1VPGL9XTGM9dp59lewUmmSxM17H/SHG8NPsYsh X-CM-Analysis: v=2.3 cv=FKU1Odgs c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=IkcTkHD0fZMA:10 a=VUJBJC2UJ8kA:10 a=7CQSdrXTAAAA:8 a=JLtsQNn4QX4pJjDu-goA:9 a=QEXdDO2ut3YA:10 a=a-qgeE7W1pNrGK8U0ZQC:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751099AbeEOXPk (ORCPT ); Tue, 15 May 2018 19:15:40 -0400 Received: from imap1.codethink.co.uk ([176.9.8.82]:58983 "EHLO imap1.codethink.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750748AbeEOXPk (ORCPT ); Tue, 15 May 2018 19:15:40 -0400 Message-ID: <1526426136.9159.85.camel@codethink.co.uk> Subject: Re: [PATCH 4.4 099/190] arm64: futex: Fix undefined behaviour with FUTEX_OP_OPARG_SHIFT usage From: Ben Hutchings To: Greg Kroah-Hartman , linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, Robin Murphy , Will Deacon , Sasha Levin Date: Wed, 16 May 2018 00:15:36 +0100 In-Reply-To: <20180411183556.339662900@linuxfoundation.org> References: <20180411183550.114495991@linuxfoundation.org> <20180411183556.339662900@linuxfoundation.org> Organization: Codethink Ltd. Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit 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: On Wed, 2018-04-11 at 20:35 +0200, Greg Kroah-Hartman wrote: > 4.4-stable review patch.  If anyone has any objections, please let me know. > > ------------------ > > > From: Will Deacon > > > [ Upstream commit 5f16a046f8e144c294ef98cd29d9458b5f8273e5 ] > > FUTEX_OP_OPARG_SHIFT instructs the futex code to treat the 12-bit oparg > field as a shift value, potentially leading to a left shift value that > is negative or with an absolute value that is significantly larger then > the size of the type. UBSAN chokes with: [...] > Whilst I think this catches all of the issues, I'd much prefer to remove > this stuff, as I think it's unused and the bugs are copy-pasted between > a bunch of architectures. [...] Indeed. That more complete fix was done upstream by: commit 30d6e0a4190d37740e9447e4e4815f06992dd8c3 Author: Jiri Slaby Date:   Thu Aug 24 09:31:05 2017 +0200     futex: Remove duplicated code and fix undefined behaviour It's a bit big for stable - though most of the changes are deletions. What do you think? Ben. -- Ben Hutchings Software Developer, Codethink Ltd.