[systemd-devel] [PATCH] SELINUX: add /sys/fs/selinux mount point to put selinuxfs

[Mimi Zohar]

On Wed, 2011-05-11 at 10:58 -0400, Eric Paris wrote:
> On Wed, May 11, 2011 at 10:54 AM, John Johansen
> <john.johansen at canonical.com> wrote:
> > On 05/11/2011 04:52 PM, Kay Sievers wrote:
> >> On Wed, May 11, 2011 at 16:43, Greg KH <greg at kroah.com> wrote:
> >>> On Wed, May 11, 2011 at 04:27:59PM +0200, Kay Sievers wrote:
> >>>> On Wed, May 11, 2011 at 15:54, Greg KH <greg at kroah.com> wrote:
> >>>>> On Wed, May 11, 2011 at 01:22:42PM +0200, John Johansen wrote:
> >>>>>> On 05/11/2011 03:59 AM, Greg KH wrote:
> >>>>>>> On Tue, May 10, 2011 at 03:55:24PM -0700, Casey Schaufler wrote:
> >>>>>>>> On 5/10/2011 3:34 PM, Greg KH wrote:
> >>>>>>>>> From: Greg Kroah-Hartman <gregkh at suse.de>
> >>>>>>>>>
> >>>>>>>>> In the interest of keeping userspace from having to create new root
> >>>>>>>>> filesystems all the time, let's follow the lead of the other in-kernel
> >>>>>>>>> filesystems and provide a proper mount point for it in sysfs.
> >>>>>>>>>
> >>>>>>>>> For selinuxfs, this mount point should be in /sys/fs/selinux/
> >>>>>>>>
> >>>>>>>> It seems that we might want this to be an LSM interface standard.
> >>>>>>>> Is the call to kobject_create_and_add and associated cleanup all
> >>>>>>>> that's required? I would want Smack to follow the convention as
> >>>>>>>> well.
> >>>>>>>
> >>>>>>> You could always just create a subdir under /sys/security/ if you have
> >>>>>>> your own filesystem, but I don't think that Smack has one, right?
> >>>>>>>
> >>>>>>> Is it going to get one?  If so, we might want to revisit the idea of
> >>>>>>> securityfs if no one is actually using it...
> >>>>>>>
> >>>>>> resending, as this looks to have been lost
> >>>>>>
> >>>>>> AppArmor, IMA, and TOMOYO are using securityfs currently.
> >>>>>
> >>>>> Great, then it will not go anywhere.
> >>>>
> >>>> Just to get an idea how all this fits together. How can TPM bios and
> >>>> IMA/AppArmor share this directory? They have their own subdirs in
> >>>> there, or both just use the securityfs infrastructure and not their
> >>>> own filesystem on top?
> >>>
> >>> Only one security module is allowed to be loaded/active at any one point
> >>> in time, so they can't step on each other.
> >>
> >> Right, but what I don't understand is CONFIG_TCG_TPM, which seem to
> >> use securityfs, and is not a LSM. This and AppArmor/IMA can be used at
> >> the same time, can't it? They share securityfs then?
> >>
> > AppArmor, Tomoyo and IMA all create their own subdirectoy under securityfs
> > so this should not be a problem
> 
> I guess the question is, should SELinux try to move to /sys/fs/selinux
> or /sys/security/selinux.  The only minor issue I see with the later
> is that it requires both sysfs and securityfs to be mounted before you
> can mount selinuxfs, whereas the first only requires sysfs.  Stephen,
> Casey, either of you have thoughts on the matter?

Just clarifying for the record that securityfs has typically been
mounted as /sys/kernel/security, not directly as /sys/security. So it
would be /sys/kernel/security/selinux that you're discussing.

Mimi