Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753866AbaB0Ssy (ORCPT ); Thu, 27 Feb 2014 13:48:54 -0500 Received: from mail-oa0-f45.google.com ([209.85.219.45]:62393 "EHLO mail-oa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751384AbaB0Sst (ORCPT ); Thu, 27 Feb 2014 13:48:49 -0500 MIME-Version: 1.0 In-Reply-To: <1393454916.14900.54.camel@x230> References: <1393445473-15068-1-git-send-email-matthew.garrett@nebula.com> <1393445473-15068-13-git-send-email-matthew.garrett@nebula.com> <20140226224141.1741a746@alan.etchedpixels.co.uk> <1393454916.14900.54.camel@x230> Date: Thu, 27 Feb 2014 10:48:48 -0800 X-Google-Sender-Auth: 5DOxdaQ6FqOSDyuFCuLtrlG_2Co Message-ID: Subject: Re: [PATCH 12/12] Add option to automatically set trusted_kernel when in Secure Boot mode From: Kees Cook To: Matthew Garrett Cc: "gnomes@lxorguk.ukuu.org.uk" , "linux-kernel@vger.kernel.org" , "jmorris@namei.org" , "hpa@zytor.com" , "gregkh@linuxfoundation.org" , "linux-security-module@vger.kernel.org" , "linux-efi@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 26, 2014 at 2:48 PM, Matthew Garrett wrote: > On Wed, 2014-02-26 at 22:41 +0000, One Thousand Gnomes wrote: >> Another issue that needs addressing is firmware. Quite a few of our >> request_firmware cases load device firmware which is not signed into DMA >> capable hardware. Probably also worth checking what the >> architectural guarantees on bogus microcode updates is. Maybe we need >> firmware signing for such cases to match the mod signing ? > > Vendors keep telling me that they're validating firmware for new > hardware, and I keep tending not to believe them. Meh. The big problem > with firmware signatures is that we don't necessarily have the right to > distribute modified versions of the firmware, so we'd need detached > signature support. I'm certainly not against this. I have been working on a patch series for this. It will have LSM hooks for validating firmware origin (via fd) and contents (via blob), similar to the changes I made for validating module origins. It just need to finish testing, and I'll post the series. If you want to check it out in its current state, it's here: http://git.kernel.org/cgit/linux/kernel/git/kees/linux.git/log/?h=fw-restrict -Kees -- Kees Cook Chrome OS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/