From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from cavan.codon.org.uk ([2a00:1098:0:80:1000:c:0:1]) by bombadil.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TQhiH-0004lj-18 for kexec@lists.infradead.org; Tue, 23 Oct 2012 16:52:22 +0000 Date: Tue, 23 Oct 2012 17:52:02 +0100 From: Matthew Garrett Subject: Re: [RFC] Kdump with signed images Message-ID: <20121023165201.GA32748@srcf.ucam.org> References: <20121018193831.GD18147@redhat.com> <874nlrv2ni.fsf@xmission.com> <20121019020630.GA27052@redhat.com> <877gqnnnf0.fsf@xmission.com> <20121019143112.GB27052@redhat.com> <871ugqb4gj.fsf@xmission.com> <20121023131854.GA16496@redhat.com> <20121023145920.GD16496@redhat.com> <20121023154123.GA30730@srcf.ucam.org> <87d309xhmc.fsf_-_@xmission.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87d309xhmc.fsf_-_@xmission.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: "Eric W. Biederman" Cc: kexec@lists.infradead.org, horms@verge.net.au, "H. Peter Anvin" , Dave Young , Vivek Goyal , Khalid Aziz On Tue, Oct 23, 2012 at 09:44:59AM -0700, Eric W. Biederman wrote: > Hogwash. The kernel verifing a signature of /sbin/kexec at exec time is > perfectly reasonable, and realistic. In fact finding a way to trust > small bits of userspace even if root is compromised seems a far superior > model to simply solving the signing problem for /sbin/kexec. The kernel verifying the signature of /sbin/kexec and then knowing that it should only grant permission to make this syscall to /sbin/kexec, without that policy being provided by userspace. -- Matthew Garrett | mjg59@srcf.ucam.org _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec