On 2018/09/17 8:00, Kees Cook wrote:

On Sun, Sep 16, 2018 at 11:49 AM, Casey Schaufler
[off-list ref] wrote:

quoted

One solution is to leave security= as is, not affecting "minor"
modules and only allowing specification of one major module, and adding

I would much prefer this, yes.

A question remains: how do we map the existing "security=" selection
of a "major" LSM against what will be next "exclusive" plus tomoyo,
and in the extreme case, nothing?

Perhaps as part of deprecating "security=", we could just declare that
it is selecting between SELinux, AppArmor, Smack, and Tomoyo only?

quoted

another boot option security.stack= that overrides a security= option
and that takes the list as you've implemented here.

or "lsm.stack=" that overrides "security=" entirely?

Yes, I think we can add new option.

For example, introducing lsm= and obsoleting security= (because total length for
kernel command line is limited while enumeration makes the parameter value longer).

  security= works like current behavior.

  lsm= requires explicit enumeration of all modules (except capability which has to
  be always enabled) which should be enabled at boot.

  security= is ignored if lsm= is specified.