Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Sat, 9 Mar 2019 15:45:36 +1100 (AEDT)
From:   James Morris <jmorris@namei.org>
To:     Matthew Garrett <mjg59@google.com>
cc:     LSM List <linux-security-module@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>
Subject: Re: [PATCH 03/27] Enforce module signatures if the kernel is locked
 down
In-Reply-To: <CACdnJuvhPd2dD7cWkxP78YMMFKU3FsigLHgkDntwhnbamNZr-w@mail.gmail.com>
Message-ID: <alpine.LRH.2.21.1903091544530.24498@namei.org>
References: <20190306235913.6631-1-matthewgarrett@google.com> <20190306235913.6631-4-matthewgarrett@google.com> <alpine.LRH.2.21.1903090959210.12052@namei.org> <CACdnJuvhPd2dD7cWkxP78YMMFKU3FsigLHgkDntwhnbamNZr-w@mail.gmail.com>
User-Agent: Alpine 2.21 (LRH 202 2017-01-01)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Fri, 8 Mar 2019, Matthew Garrett wrote:

> On Fri, Mar 8, 2019 at 3:00 PM James Morris <jmorris@namei.org> wrote:
> >
> > On Wed, 6 Mar 2019, Matthew Garrett wrote:
> >
> > > From: David Howells <dhowells@redhat.com>
> > >
> > > If the kernel is locked down, require that all modules have valid
> > > signatures that we can verify.
> >
> > Perhaps note that this won't cover the case where folk are using DM-Verity
> > with a signed root hash for verifying kernel modules.
> 
> Mm. I can't see a terribly good way of doing this generically -
> loadpin gives no indication to the module loading code that it comes
> from a trusted source. Would making the lockdown/module signature
> enforcement a separate config option be reasonable?

I was just suggest documenting this.

-- 
James Morris
<jmorris@namei.org>