Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751159Ab3IJTSc (ORCPT ); Tue, 10 Sep 2013 15:18:32 -0400 Received: from mail.lang.hm ([64.81.33.126]:52685 "EHLO bifrost.lang.hm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750923Ab3IJTSa (ORCPT ); Tue, 10 Sep 2013 15:18:30 -0400 Date: Tue, 10 Sep 2013 12:17:57 -0700 (PDT) From: David Lang X-X-Sender: dlang@asgard.lang.hm To: Kees Cook cc: "gregkh@linuxfoundation.org" , "H. Peter Anvin" , Matthew Garrett , Henrique de Moraes Holschuh , "Valdis.Kletnieks@vt.edu" , "linux-kernel@vger.kernel.org" , "linux-efi@vger.kernel.org" , "jmorris@namei.org" , "linux-security-module@vger.kernel.org" Subject: Re: [PATCH 00/12] One more attempt at useful kernel lockdown In-Reply-To: Message-ID: References: <1378767723.17982.27.camel@x230.lan> <1378774394.17982.36.camel@x230.lan> <1378781715.17982.42.camel@x230.lan> <1378785208.17982.54.camel@x230.lan> <20130910172318.GB21530@khazad-dum.debian.net> <1378837571.17615.0.camel@x230.lan> <522F6519.4030004@zytor.com> <20130910185149.GC5559@kroah.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1678 Lines: 41 On Tue, 10 Sep 2013, Kees Cook wrote: > Subject: Re: [PATCH 00/12] One more attempt at useful kernel lockdown > > On Tue, Sep 10, 2013 at 11:51 AM, gregkh@linuxfoundation.org > wrote: >> On Tue, Sep 10, 2013 at 11:29:45AM -0700, H. Peter Anvin wrote: >>> On 09/10/2013 11:26 AM, Matthew Garrett wrote: >>>> On Tue, 2013-09-10 at 14:23 -0300, Henrique de Moraes Holschuh wrote: >>>>> On Tue, 10 Sep 2013, Matthew Garrett wrote: >>>>>> That's why modern systems require signed firmware updates. >>>>> >>>>> Linux doesn't. Is someone working on adding signature support to the >>>>> runtime firmware loader? >>>> >>>> It'd be simple to do so, but so far the model appears to be that devices >>>> that expect signed firmware enforce that themselves. >>>> >>> >>> Most devices do absolutely no verification on the firmware, and simply >>> trust the driver. >>> >>> So signing firmware is probably critical. >> >> How are you going to "validate" that the firmware is correct, given >> that it's just a "blob" living in the linux-firmware tree. If you sign >> it, what is that saying? > > In theory these blobs are traceable to a manufacturer. It's not really > an indication that it's "safe" more than it's an indication that it > hasn't been changed. But I haven't chased this very hard yet because > of below... well, not if you are trying to defend against root breaking in to the machine. David Lang -- 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/