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From:   Matthew Garrett <mjg59@google.com>
Date:   Thu, 27 Jun 2019 16:17:46 -0700
Message-ID: <CACdnJuvRtQWFknzxLwKc6erCBZ3+6tXmabEdRuXXGTGrYEAp6w@mail.gmail.com>
Subject: Re: [PATCH V34 09/29] kexec_file: Restrict at runtime if the kernel
 is locked down
To:     James Morris <jmorris@namei.org>
Cc:     LSM List <linux-security-module@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>,
        Jiri Bohac <jbohac@suse.cz>,
        David Howells <dhowells@redhat.com>, kexec@lists.infradead.org
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On Thu, Jun 27, 2019 at 11:14 AM James Morris <jmorris@namei.org> wrote:
>
> On Thu, 27 Jun 2019, Matthew Garrett wrote:
>
> > By that metric, on a secure boot system how do we determine that code
> > running in the firmware environment wasn't compromised before it
> > launched the initial signed kernel?
>
> Remote attestation tied to a hardware root of trust, before allowing
> access to any further resources.

If you use IMA you can get the same guarantees over kexec.