Re: [PATCH] securityfs

James Morris
2005-07-06T19:58:12Z

On Wed, 6 Jul 2005, Stephen Smalley wrote:

> > Stephen: opinions on this?
>
> The reason for creating a kernel mount of selinuxfs at that point is so
> that the selinuxfs_mount vfsmount and selinux_null dentry are available
> for flush_unauthorized_files to use.

When exactly is this needed? The securityfs mountpoint will be available
via a core_initcall, after which we can initialize the selinux subtree.

> Userspace compatibility is obviously a concern for such a change.
> libselinux determines where selinuxfs is mounted during library
> initialization by checking /proc/mounts for selinuxfs, and rc.sysinit
> does likewise.
>
> /sbin/init performs the initial mount of selinuxfs prior
> to initial policy load.

With securityfs, we'd have /sys/kernel/security/selinux configured during
kernel initialization.

> Further, the existence of selinuxfs
> in /proc/filesystems is used as a test of whether SELinux was enabled in
> the kernel (e.g. is_selinux_enabled in libselinux).

Could be a simple change to look for the presence of
/sys/kernel/security/selinux

> I'm not sure such a change is worthwhile for SELinux; large amount of
> disruption for little real gain.

I think it should reduce and simplify the SELinux kernel code, with less
filesystems in the kernel, consolidating several potential projects into
the same security filesystem.

- James
--
James Morris
<jmorris@redhat.com>