From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=I82Q=LM=vger.kernel.org=linux-kernel-owner@kernel.org>
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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,
	MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 D3B49C433F5
	for <linux-kernel@archiver.kernel.org>; Wed, 29 Aug 2018 07:08:47 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.kernel.org (Postfix) with ESMTP id 67E492084D
	for <linux-kernel@archiver.kernel.org>; Wed, 29 Aug 2018 07:08:47 +0000 (UTC)
DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 67E492084D
Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de
Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1727615AbeH2LEK (ORCPT
        <rfc822;linux-kernel@archiver.kernel.org>);
        Wed, 29 Aug 2018 07:04:10 -0400
Received: from mx2.suse.de ([195.135.220.15]:52292 "EHLO mx1.suse.de"
        rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP
        id S1727107AbeH2LEK (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 29 Aug 2018 07:04:10 -0400
X-Virus-Scanned: by amavisd-new at test-mx.suse.de
Received: from relay2.suse.de (unknown [195.135.220.254])
        by mx1.suse.de (Postfix) with ESMTP id 0C447ABA2;
        Wed, 29 Aug 2018 07:08:43 +0000 (UTC)
Date:   Wed, 29 Aug 2018 09:09:07 +0200
From:   Borislav Petkov <bp@suse.de>
To:     Jann Horn <jannh@google.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H . Peter Anvin" <hpa@zytor.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        kernel list <linux-kernel@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>, security@kernel.org
Subject: Re: [PATCH v2] x86/dumpstack: don't dump kernel memory based on
 usermode RIP
Message-ID: <20180829070907.GA6337@nazgul.tnic>
References: <20180828154901.112726-1-jannh@google.com>
 <20180828162551.GA4950@nazgul.tnic>
 <CAG48ez3N5wBUEDCDaSzWOWjs5rYrQ4QgNTYT=PmYmFQAcqfA-w@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <CAG48ez3N5wBUEDCDaSzWOWjs5rYrQ4QgNTYT=PmYmFQAcqfA-w@mail.gmail.com>
User-Agent: Mutt/1.6.0 (2016-04-01)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Aug 28, 2018 at 06:29:43PM +0200, Jann Horn wrote:
> No, you can also get user opcode bytes printed by WARN() and friends.
> When you add a WARN() in the pagefault handler, you get something like

Ok, let's always do the checking then - who knows in what context we
might be dumping opcodes so we better be prepared.

Thx.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--