Re: [PATCH security-next v4 23/32] selinux: Remove boot parameter
From: James Morris
Date: Tue Oct 02 2018 - 18:06:36 EST
On Tue, 2 Oct 2018, Kees Cook wrote:
> On Tue, Oct 2, 2018 at 11:57 AM, John Johansen
> <john.johansen@xxxxxxxxxxxxx> wrote:
> > Under the current scheme
> >
> > lsm.enabled=selinux
> >
> > could actually mean selinux,yama,loadpin,something_else are
> > enabled. If we extend this behavior to when full stacking lands
> >
> > lsm.enabled=selinux,yama
> >
> > might mean selinux,yama,apparmor,loadpin,something_else
> >
> > and what that list is will vary from kernel to kernel, which I think
> > is harder for the user than the lsm.enabled list being what is
> > actually enabled at boot
>
> Ah, I think I missed this in your earlier emails. What you don't like
> here is that "lsm.enable=" is additive. You want it to be explicit.
>
This is a path to madness.
How about enable flags set ONLY per LSM:
lsm.selinux.enable=x
lsm.apparmor.enable=x
With no lsm.enable, and removing selinux=x and apparmor=x.
Yes this will break existing docs, but they can be updated for newer
kernel versions to say "replace selinux=0 with lsm.selinux.enable=0" from
kernel X onwards.
Surely distro packages and bootloaders are able to cope with changes to
kernel parameters?
We can either take a one-time hit now, or build new usability debt, which
will confuse people forever.
--
James Morris
<jmorris@xxxxxxxxx>