From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755778AbbBPL4G (ORCPT ); Mon, 16 Feb 2015 06:56:06 -0500 Received: from mail.skyhub.de ([78.46.96.112]:56447 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755337AbbBPL4E (ORCPT ); Mon, 16 Feb 2015 06:56:04 -0500 Date: Mon, 16 Feb 2015 12:55:17 +0100 From: Borislav Petkov To: Kees Cook Cc: Jiri Kosina , "H. Peter Anvin" , LKML , live-patching@vger.kernel.org, Linux-MM , "x86@kernel.org" Subject: Re: [PATCH v2] x86, kaslr: propagate base load address calculation Message-ID: <20150216115517.GB9500@pd.tnic> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 13, 2015 at 03:25:26PM -0800, Kees Cook wrote: > No, no; I agree: a malicious boot loader is a lost cause. I mean > mostly from a misbehavior perspective. Like, someone sees "kaslr" in > the setup args and thinks they can set it to 1 and boot a kernel, etc. > Or they set it to 0, but they lack HIBERNATION and "1" gets appended, > but the setup_data parser sees the boot-loader one set to 0, etc. I'm > just curious if we should avoid getting some poor system into a > confusing state. Well, we can apply the rule of the last setting sticks and since the kernel is always going to be adding the last setup_data element of type SETUP_KASLR (the boot loader ones will be somewhere on the list in-between and we add to the end), we're fine, no? -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. --