Re: linux-next: manual merge of the selinux tree with the vfs tree

On 11/29/2018 3:51 PM, Al Viro wrote:

I've added linux-security-module to the CC list.

On Thu, Nov 29, 2018 at 05:23:24PM -0500, Paul Moore wrote:

quoted

quoted

OK, I will verify that the SELinux submount fix rebased on top of
vfs/work.mount in the way I suggested above passes the same testing
(seliinux-testsuite + NFS crossmnt reproducer). I am now building two
kernels (vfs/work.mount with and without the fix) to test. Let me know
if there is anything more to do.

Thanks.

The big thing is just making sure that we don't regress on the fix in
selinux/next if/when David's mount rework hits Linus' tree.

FWIW, the whole thing is getting massaged/reordered/etc. and I would
like some input from you guys at some point - assuming that I recover
the ability to talk about LSM without obscenities...

Question: what *should* happen if we try to cross into a submount and find
that the thing on the other side is already mounted elsewhere, with incompatible
LSM options?  Ditto for referrals, with an extra twist - what if we are given
3 alternatives, the first two already mounted elsewhere with incompatible
options, the third one not mounted anywhere yet?

I fear that the safe answer and the containers answer are likely
to differ. The safe answer has to be to refuse the mount.

Incidentally, should smack have ->sb_clone_mnt_opts()?

Probably, but I could never figure out what it was for,
and haven't identified a problem with not using it.