Received: by 2002:ac0:aed5:0:0:0:0:0 with SMTP id t21csp5314328imb; Thu, 7 Mar 2019 12:42:24 -0800 (PST) X-Google-Smtp-Source: APXvYqwHLGnH0PzVvAsqGSiPMPjAhvqFuljJylmFf26GPUo/SM7AKyfSExa0yg0gqRxI98PkalHc X-Received: by 2002:a62:4754:: with SMTP id u81mr14818917pfa.66.1551991344495; Thu, 07 Mar 2019 12:42:24 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1551991344; cv=none; d=google.com; s=arc-20160816; b=f3A975cZT5JZjtAvFLR+jSu+95tdrDTCqHHn15ii7Tz5yR2HhSQAKEpfGEnlnblzAc kO2Ozu/qSlrnL1zhR6BjInYQzvaGJ2XjoD5lQLktmX1YTTljQnZWEaY2GD2q8YOZUHbe Sq+UbK3ipuB99SqByjMJU8Leg1+8Ya6YAi8JnYGToOkktEVZ+sIMgqei+WLiWV7f+Yq/ 8+0fl7knk9lAk1e2/PGqaHkboKJgIA4FSFXL3qRwzAKRw9vkW1FszN2Avk0W8Xk0k7u+ ZDiCqihzJbUkQyLQgBpNU2XfhWGBiqiZbykKUZD79o95aYTW/iw4o1zRSNCqUqBRGPh5 hTqA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:from:references:cc:to:subject; bh=LagVpvCuga7jhbwXkezShgm1GG5eMV3nPih/FRicb8Y=; b=05/6knPNxK7TVSdd/TCtG5BZAmKmbOsedGj+a2dvH+IYv8NcHVfzkaB2q+s5OfbKAQ xPdjZtqsB45faTscF/AwCg+m3xYPmPDcUIRy2zJXezhOCM25bO9Zgf/omsy0z85oG2W0 TNIDwZKRMjocvn5T4FUnSswGHEa23XOpNRzsc3VQXcRoHFKAGhn2KUSa8G6ZKmbuQ85i fxPi23RHQ5pi9V44QW6EBx1blBhJpXE9r5oP3YtL42/pwei+JAOrtbQDsySYWrjoqk7Z 3D+kg3Y9Yk1GJjRqPwsYX9b4Yi9HdBo2sf6gyfNSsw9+shnhQZ9QkS1zhAPVk/bnX+ru Nkow== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=virtuozzo.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id z13si4401260pgv.508.2019.03.07.12.42.09; Thu, 07 Mar 2019 12:42:24 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=virtuozzo.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726242AbfCGUkX (ORCPT + 99 others); Thu, 7 Mar 2019 15:40:23 -0500 Received: from relay.sw.ru ([185.231.240.75]:58482 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726166AbfCGUkW (ORCPT ); Thu, 7 Mar 2019 15:40:22 -0500 Received: from [192.168.15.238] by relay.sw.ru with esmtp (Exim 4.91) (envelope-from ) id 1h1zoO-0003gj-Ee; Thu, 07 Mar 2019 23:40:16 +0300 Subject: Re: [PATCH 18/20] objtool: Add UACCESS validation To: Peter Zijlstra Cc: Linus Torvalds , Thomas Gleixner , Peter Anvin , Julien Thierry , Will Deacon , Andy Lutomirski , Ingo Molnar , Catalin Marinas , James Morse , valentin.schneider@arm.com, Brian Gerst , Josh Poimboeuf , Andrew Lutomirski , Borislav Petkov , Denys Vlasenko , Linux List Kernel Mailing , Dmitry Vyukov , Steven Rostedt References: <20190307114511.870090179@infradead.org> <20190307115200.697533978@infradead.org> <20190307174135.GJ32477@hirez.programming.kicks-ass.net> <6a4875bd-2b22-91e4-cbe2-b01c12786a1b@virtuozzo.com> <20190307203318.GM32477@hirez.programming.kicks-ass.net> From: Andrey Ryabinin Message-ID: Date: Thu, 7 Mar 2019 23:40:06 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.2 MIME-Version: 1.0 In-Reply-To: <20190307203318.GM32477@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/7/19 11:33 PM, Peter Zijlstra wrote: > On Thu, Mar 07, 2019 at 11:15:42PM +0300, Andrey Ryabinin wrote: >> >> >> On 3/7/19 8:41 PM, Peter Zijlstra wrote: >>> On Thu, Mar 07, 2019 at 08:33:26AM -0800, Linus Torvalds wrote: >>>> On Thu, Mar 7, 2019 at 3:52 AM Peter Zijlstra wrote: >>>>> >>>>> XXX: are we sure we want __memset marked AC-safe? >>>> >>>> It's certainly one of the safer functions to call with AC set, but it >>>> sounds wrong anyway. It's not like it's likely to leak kernel data >>>> (most memset's are with 0, and even the non-zero ones I can't imagine >>>> are sensitive - more like poison values etc). >>>> >>>> What's the call site that made you go "just add __memset() to the list"? >>> >>> __asan_{,un}poinson_stack_memory() >> >> These two can be called only with CONFIG_KASAN_EXTRA=y which >> was removed very recently, so it should be safe to delete these functions. > > Ooh shiny. Clearly my tree still has them; what commit do I need to look > for? > commit 7771bdbbfd3d6f204631b6fd9e1bbc30cd15918e