Received: by 2002:a25:4158:0:0:0:0:0 with SMTP id o85csp947087yba; Thu, 4 Apr 2019 00:49:15 -0700 (PDT) X-Google-Smtp-Source: APXvYqw3YvVUsWXIsLjovYZGIfEURCEkdfWsJxNmXGKkMiofPAhLaQ7ltGCwLxUYArSUHketACBu X-Received: by 2002:aa7:864a:: with SMTP id a10mr4308980pfo.181.1554364155303; Thu, 04 Apr 2019 00:49:15 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1554364155; cv=none; d=google.com; s=arc-20160816; b=bozQPaHRxBG5dOvYbUFq41pCIxDo7zk1wOq6+xpYt8m4cinAlVvlqS6gdv7nlM986U aKoeyHW18RaPxEDlky+4ZxOTJQw8UCjUKDREJD9B3tzZO91um42Gdzmh9Q3Z0Q1CHYu4 MPgi3EpaIWAtF+5Y51Pqadomp4ChxTY9LOGzV8Iu10GNIJM+N2DYFNS5IuyYjTb8Mh+A 1YKcHlPF3W6jM8m4MiCya/tyPNFp82nPsOHAgHyeZ5gKDl1jk1H8IMBF0tfFGFMwYx7x UPhVoIBz26OM48h+FSdR+aMUzxb+uHZ+DpxWgc7efTuF/uv63kSXEJamqYDAh0CI6LZ5 xECA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:user-agent:references :message-id:in-reply-to:subject:cc:to:from:date; bh=R2ElpRc3DD5jJy5wH9Z43x4HIaNvOVLFxCvzAxVtEyI=; b=VEhdaHVr7Dao6nwChiQ1/BCCyPbS2ecmNsykeJQguDq6mncw5TlMG7CGAVTG/CU5kc 6e5gKpZNlWeHEimMpGROShiiiYX2YHEFoclIp6iRTwAAoPg6q4CwXhvhN7S9GxuMAcmn 2T84AjmTdTu+BkWYPGaBNCm5N6QmUZWqwfvHeXR8NctTJnFXuQXpserL7XfOkih5sMW0 8qd+7XZbPFyDqAk2LHy4KzwkwynEI+SJRe9IgGYNzHB/ZhVH8/4mg4fBM6Y5699ticbS /XCwF8el0N8btVDYssz+JQPEQIphceo8ayPH5Sqvk6IN/swaVesMErhRL/octMjWBoyy SYLw== 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 77si1315030pfs.287.2019.04.04.00.49.00; Thu, 04 Apr 2019 00:49:15 -0700 (PDT) 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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727287AbfDDHsB (ORCPT + 99 others); Thu, 4 Apr 2019 03:48:01 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:43753 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725914AbfDDHsA (ORCPT ); Thu, 4 Apr 2019 03:48:00 -0400 Received: from p5492e2fc.dip0.t-ipconnect.de ([84.146.226.252] helo=nanos) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1hBx6G-0000NA-UG; Thu, 04 Apr 2019 09:47:53 +0200 Date: Thu, 4 Apr 2019 09:47:52 +0200 (CEST) From: Thomas Gleixner To: Matthew Garrett cc: jmorris@namei.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-api@vger.kernel.org, luto@kernel.org, Matthew Garrett , Steven Rostedt , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org Subject: Re: [PATCH V32 19/27] x86/mmiotrace: Lock down the testmmiotrace module In-Reply-To: <20190404003249.14356-20-matthewgarrett@google.com> Message-ID: References: <20190404003249.14356-1-matthewgarrett@google.com> <20190404003249.14356-20-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 Wed, 3 Apr 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 Reviewed-by: Thomas Gleixner