From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DBB07C433ED for ; Thu, 1 Apr 2021 08:38:09 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 38F3860190 for ; Thu, 1 Apr 2021 08:38:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 38F3860190 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8B7D16B0080; Thu, 1 Apr 2021 04:38:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 867EB6B0081; Thu, 1 Apr 2021 04:38:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7083B6B0082; Thu, 1 Apr 2021 04:38:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0141.hostedemail.com [216.40.44.141]) by kanga.kvack.org (Postfix) with ESMTP id 5717E6B0080 for ; Thu, 1 Apr 2021 04:38:08 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 14BB38249980 for ; Thu, 1 Apr 2021 08:38:08 +0000 (UTC) X-FDA: 77983145856.10.6DC9131 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf14.hostedemail.com (Postfix) with ESMTP id E424FC0007C5 for ; Thu, 1 Apr 2021 08:38:05 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id C6D0B61041; Thu, 1 Apr 2021 08:38:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617266286; bh=pL7zEm/CJ6Uq13TbvMopTgicNXFZzItUs41gFNFs0bo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=A3X3lduCFkIuAeuQcqpzhul7wvKwDj5UjZ40gX0BhH6coMkam04N1fMhBXiO1k9fr Qx/8Cp+zmkSw5yt/9WD3OWEBwEdVVUiTgmrKXPktPG5MJhpkzp1IqJLPCbqq2ePs32 NzwqEkscV/FJQFSYJe0Z+pA7s1+1j2kz8cRLj9B2ZGRPbxRir0oMbkz4NORBnn08Qw zpEovn8ARnysgKDkNQpa5nWT4UqQLnGUIgZL92lSn8A0CTU6eFdvu51VF/lz3gas5G NbEBSMnsjL1na3BP/51tBCx3wTgdCqXYFtiXlE20KJqh/YGMRt2tzdaxvdOsy5SBYF Da/Tpgqva8b+A== Date: Thu, 1 Apr 2021 09:37:59 +0100 From: Will Deacon To: Kees Cook Cc: Catalin Marinas , Mark Rutland , Thomas Gleixner , Elena Reshetova , x86@kernel.org, Andy Lutomirski , Peter Zijlstra , Alexander Potapenko , Alexander Popov , Ard Biesheuvel , Jann Horn , Vlastimil Babka , David Hildenbrand , Mike Rapoport , Andrew Morton , Jonathan Corbet , Randy Dunlap , kernel-hardening@lists.openwall.com, linux-hardening@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v9 0/6] Optionally randomize kernel stack offset each syscall Message-ID: <20210401083758.GA8745@willie-the-truck> References: <20210331205458.1871746-1-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210331205458.1871746-1-keescook@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Rspamd-Queue-Id: E424FC0007C5 X-Stat-Signature: c4iwuxihgemffuxe3ytjaygxa1z6dhmx X-Rspamd-Server: rspam02 Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf14; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617266285-948499 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Kees, On Wed, Mar 31, 2021 at 01:54:52PM -0700, Kees Cook wrote: > Hi Will (and Mark and Catalin), > > Can you take this via the arm64 tree for v5.13 please? Thomas has added > his Reviewed-by, so it only leaves arm64's. :) Sorry, these got mixed up in my inbox so I just replied to v7 and v8 and then noticed v9. Argh! However, I think the comments still apply: namely that the dummy "=m" looks dangerous to me and I think you're accessing pcpu variables with preemption enabled for the arm64 part: https://lore.kernel.org/r/20210401083034.GA8554@willie-the-truck https://lore.kernel.org/r/20210401083430.GB8554@willie-the-truck Will