On Wed, Dec 12, 2018 at 5:19 PM James Morris [off-list ref] wrote:

The SELinux testsuite is failing in the overlayfs tests in current -rc
kernels. I bisected the issue to

commit 007ea44892e6fa963a0876a979e34890325c64eb
Author: Miklos Szeredi [off-list ref]
Date:   Fri Oct 26 23:34:39 2018 +0200

    ovl: relax permission checking on underlying layers

    Make permission checking more consistent:

     - special files don't need any access check on underling fs

     - exec permission check doesn't need to be performed on underlying fs

    Reported-by: "J. Bruce Fields" [off-list ref]
    Signed-off-by: Miklos Szeredi [off-list ref]

Reverting this commit fixes the testsuite failure.

Is there any more information on the rationale for the change?

This is a known problem, see the archive link below, with Miklos
promising to send a revert to Linus for v4.20.  I just pinged him
earlier this week to remind him, but I haven't heard back yet and I
don't see anything in Linus' tree.

I would much prefer if Miklos sent the revert, but if he doesn't send
the revert by the end of the week, I'm going to send one next week.

https://lore.kernel.org/selinux/CAJfpeguJoEOEjQs4ZpJQaJXF-xCnevUApzNobwmqNX27KQ4vHQ@mail.gmail.com (local)

-- 
paul moore
www.paul-moore.com