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Date:   Tue, 5 Feb 2019 13:13:37 -0800
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Mimi Zohar <zohar@linux.ibm.com>
Cc:     linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jessica Yu <jeyu@kernel.org>,
        David Howells <dhowells@redhat.com>,
        Seth Forshee <seth.forshee@canonical.com>,
        Justin Forbes <jforbes@redhat.com>,
        Matthew Garrett <mjg59@google.com>
Subject: Re: [PATCH] x86/ima: require signed kernel modules
Message-ID: <20190205211337.GX11489@garbanzo.do-not-panic.com>
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On Tue, Feb 05, 2019 at 07:24:39AM -0500, Mimi Zohar wrote:
> On Mon, 2019-02-04 at 14:30 -0800, Luis Chamberlain wrote:
> > On Mon, Feb 04, 2019 at 05:05:10PM -0500, Mimi Zohar wrote:
> > > On Mon, 2019-02-04 at 12:38 -0800, Luis Chamberlain wrote:
> 
> > > I don't see a need for an additional LSM just for verifying kernel
> > > module signatures.
> > 
> > But it is one, module signing was just spawned pre the boom of LSMs.
> > 
> > I do believe that treating the code as such would help with its reading
> > and long term maintenance.
> > 
> > Anyway, I had to try to convince you.
> 
> Perhaps, after IMA supports appended signatures (for kernel modules),
> I could see making the existing kernel module appended signature
> verification an LSM.

I don't see why wait.

> For now, other than updating the comment, would you be willing to add
> your Review/Ack to this patch?

But I don't particularly like the changes, I still believe trying to
LSM'ify kernel module signing would be a better start to help with
long term maintenace on this code.

Also, do we have selftests implemented to ensure we don't regress with
your changes?

  Luis