Re: [PATCH] SELinux: Measure state and hash of policy using IMA

From: Stephen Smalley <stephen.smalley.work@gmail.com>
To: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Cc: Paul Moore <paul@paul-moore.com>,
	Ondrej Mosnacek <omosnace@redhat.com>,
	Mimi Zohar <zohar@linux.ibm.com>,
	Casey Schaufler <casey@schaufler-ca.com>,
	Tyler Hicks <tyhicks@linux.microsoft.com>,
	tusharsu@linux.microsoft.com, Sasha Levin <sashal@kernel.org>,
	James Morris <jmorris@namei.org>,
	linux-integrity@vger.kernel.org,
	SElinux list <selinux@vger.kernel.org>,
	LSM List <linux-security-module@vger.kernel.org>,
	linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] SELinux: Measure state and hash of policy using IMA
Date: Wed, 26 Aug 2020 08:51:26 -0400	[thread overview]
Message-ID: <CAEjxPJ4TkEEKG+pXwUjyysov1s1mFk4jbGGVyC7ghmpfd3TJ4w@mail.gmail.com> (raw)
In-Reply-To: <07854807-c495-b7e5-fc44-26d78ff14f1b@linux.microsoft.com>

On Tue, Aug 25, 2020 at 4:49 PM Lakshmi Ramasubramanian
<nramas@linux.microsoft.com> wrote:
>
> On 8/24/20 3:18 PM, Paul Moore wrote:
>
> Hi Paul,
>
> >>>>> Is Ondrej's re-try approach I need to use to workaround policy reload issue?
> >>>>
> >>>> No, I think perhaps we should move the mutex to selinux_state instead
> >>>> of selinux_fs_info.  selinux_fs_info has a pointer to selinux_state so
> >>>> it can then use it indirectly.  Note that your patches are going to
> >>>> conflict with other ongoing work in the selinux next branch that is
> >>>> refactoring policy load and converting the policy rwlock to RCU.
> >>>
> >>> Yeah, and I'm experimenting with a patch on top of Stephen's RCU work
> >>> that would allow you to do this in a straightforward way without even
> >>> messing with the fsi->mutex. My patch may or may not be eventually
> >>> committed, but either way I'd recommend holding off on this for a
> >>> while until the dust settles around the RCU conversion.
> >>
> >> I can make the SELinux\IMA changes in "selinux next branch" taking
> >> dependencies on Stephen's patches + relevant IMA patches.
> >
> > I know it can be frustrating to hear what I'm about to say, but the
> > best option is probably just to wait a little to let things settle in
> > the SELinux -next branch.  There is a lot of stuff going on right now
> > with patches flooding in (at least "flooding" from a SELinux kernel
> > development perspective) and we/I've haven't gotten through all of
> > them yet.
> >
>
> Could you please let me know when the current set of changes in SELinux
> next branch would be completed and be ready to take new changes?
>
> I mean, roughly - would it be a month from now or you expect that to
> take longer?

I can't speak for Paul but I would expect it to be sooner rather than
later. Ondrej has some follow ups on top of my policy rcu conversion
but then it should be good to go.