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From:   Matthew Garrett <mjg59@google.com>
Date:   Thu, 7 Mar 2019 09:32:24 -0800
Message-ID: <CACdnJuutrCYOoppScar53nfNnsrE6Oq36ayRGnJRLgh202aasw@mail.gmail.com>
Subject: Re: [PATCH 09/27] hibernate: Disable when the kernel is locked down
To:     Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc:     jmorris@namei.org,
        LSM List <linux-security-module@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>
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On Thu, Mar 7, 2019 at 6:55 AM Alan Cox <gnomes@lxorguk.ukuu.org.uk> wrote:
>
> On Wed,  6 Mar 2019 15:58:55 -0800
> Matthew Garrett <matthewgarrett@google.com> wrote:
>
> > From: Josh Boyer <jwboyer@fedoraproject.org>
> >
> > There is currently no way to verify the resume image when returning
> > from hibernate.  This might compromise the signed modules trust model,
> > so until we can work with signed hibernate images we disable it when the
> > kernel is locked down.
>
> That one is a bit worrying since whilst the other stuff may be useful in
> some business environments, mandatory hibernate not suspend to RAM is a
> common corporate IT policy because of concerns about theft and recovery
> of memory contents.

Suse have a solution for this that I'd like to see pushed again, but
from a practical perspective enterprise distributions have been
shipping this for some time without significant obvious customer
complaint.