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=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 23049C43613 for ; Sun, 23 Jun 2019 11:10:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC9AE20679 for ; Sun, 23 Jun 2019 11:10:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726484AbfFWLI6 (ORCPT ); Sun, 23 Jun 2019 07:08:58 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:33207 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726350AbfFWLI6 (ORCPT ); Sun, 23 Jun 2019 07:08:58 -0400 Received: from p5b06daab.dip0.t-ipconnect.de ([91.6.218.171] helo=nanos) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1hf0Mf-00080j-Ge; Sun, 23 Jun 2019 13:08:53 +0200 Date: Sun, 23 Jun 2019 13:08:52 +0200 (CEST) From: Thomas Gleixner To: Matthew Garrett cc: jmorris@namei.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, David Howells , Matthew Garrett , Steven Rostedt , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org Subject: Re: [PATCH V34 20/29] x86/mmiotrace: Lock down the testmmiotrace module In-Reply-To: <20190622000358.19895-21-matthewgarrett@google.com> Message-ID: References: <20190622000358.19895-1-matthewgarrett@google.com> <20190622000358.19895-21-matthewgarrett@google.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 21 Jun 2019, Matthew Garrett wrote: > From: David Howells > > The testmmiotrace module shouldn't be permitted when the kernel is locked > down as it can be used to arbitrarily read and write MMIO space. This is > a runtime check rather than buildtime in order to allow configurations > where the same kernel may be run in both locked down or permissive modes > depending on local policy. > > Suggested-by: Thomas Gleixner > Signed-off-by: David Howells Signed-off-by: Matthew Garrett > cc: Thomas Gleixner > cc: Steven Rostedt > cc: Ingo Molnar > cc: "H. Peter Anvin" > cc: x86@kernel.org Reviewed-by: Thomas Gleixner