ACK: [Patch][Disco] apparmor: Restore Y/N in /sys for apparmor's "enabled"

[Seth Forshee]

On Tue, Apr 09, 2019 at 04:29:47AM -0700, John Johansen wrote:
> The attached patch fixes bug 1823379. It is working its way upstream for the 5.1 kernel, but I don't have an upstream sha1 to reference yet

> From 4a9047bfe76e2d36cfe8ea6e4a89200fd4ca616d Mon Sep 17 00:00:00 2001
> From: Kees Cook <keescook at chromium.org>
> Date: Mon, 8 Apr 2019 09:07:06 -0700
> Subject: [PATCH] apparmor: Restore Y/N in /sys for apparmor's "enabled"
> 
> Before commit c5459b829b71 ("LSM: Plumb visibility into optional "enabled"
> state"), /sys/module/apparmor/parameters/enabled would show "Y" or "N"
> since it was using the "bool" handler. After being changed to "int",
> this switched to "1" or "0", breaking the userspace AppArmor detection
> of dbus-broker. This restores the Y/N output while keeping the LSM
> infrastructure happy.
> 
> Before:
> 	$ cat /sys/module/apparmor/parameters/enabled
> 	1
> 
> After:
> 	$ cat /sys/module/apparmor/parameters/enabled
> 	Y
> 
> BugLink: http://bugs.launchpad.net/bugs/1823379
> Reported-by: David Rheinsberg <david.rheinsberg at gmail.com>
> Link: https://lkml.kernel.org/r/CADyDSO6k8vYb1eryT4g6+EHrLCvb68GAbHVWuULkYjcZcYNhhw@mail.gmail.com
> Fixes: c5459b829b71 ("LSM: Plumb visibility into optional "enabled" state")
> Signed-off-by: Kees Cook <keescook at chromium.org>
> Signed-off-by: John Johansen <john.johansen at canonical.com>

Tested against the lxc test suite and confirmed that this fixes the bug.

Acked-by: Seth Forshee <seth.forshee at canonical.com>

This should be sauce as it's not upstream yet, but that can be fixed
when applying. Thanks!