From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1KxSez-0000Bj-CN for mharc-grub-devel@gnu.org; Tue, 04 Nov 2008 15:37:57 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KxSew-0000AR-Kq for grub-devel@gnu.org; Tue, 04 Nov 2008 15:37:54 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KxSeu-000096-Lu for grub-devel@gnu.org; Tue, 04 Nov 2008 15:37:53 -0500 Received: from [199.232.76.173] (port=54015 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KxSeu-000093-Ik for grub-devel@gnu.org; Tue, 04 Nov 2008 15:37:52 -0500 Received: from aybabtu.com ([69.60.117.155]:36232) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KxSeu-0005YQ-Qe for grub-devel@gnu.org; Tue, 04 Nov 2008 15:37:53 -0500 Received: from [192.168.10.10] (helo=thorin) by aybabtu.com with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.69) (envelope-from ) id 1KxSdt-0000QF-0H for grub-devel@gnu.org; Tue, 04 Nov 2008 21:36:49 +0100 Received: from rmh by thorin with local (Exim 4.63) (envelope-from ) id 1KxSdX-0007TG-Eh for grub-devel@gnu.org; Tue, 04 Nov 2008 21:36:27 +0100 Date: Tue, 4 Nov 2008 21:36:27 +0100 From: Robert Millan To: grub-devel@gnu.org Message-ID: <20081104203627.GA28595@thorin> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Organization: free as in freedom X-Message-Flag: Worried about Outlook viruses? Switch to Thunderbird! www.mozilla.com/thunderbird X-Debbugs-No-Ack: true User-Agent: Mutt/1.5.13 (2006-08-11) X-detected-operating-system: by monty-python.gnu.org: Genre and OS details not recognized. Subject: Multiboot2 header X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Nov 2008 20:37:55 -0000 The Multiboot2 draft says a Multiboot2 header must be included in the OS image. However, our code assumes (in code itself and in comments) that for MB2 this is optional. As a consequence, if you feed GRUB's multiboot loader any ELF, it will attempt to load it. I think this is very confusing for those developing a Multiboot _1_ OS. If they happen to make a mistake and put the MB1 header too high or unaligned, GRUB won't tell them about it but instead fail in a very confusing way. So I assume (I'd like to!) that the correct one is the draft, and it's the code that should be changed to reject executables that don't have either MB1 or MB2 headers? -- Robert Millan The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and how) you may access your data; but nobody's threatening your freedom: we still allow you to remove your data and not access it at all."