Comment 19 for bug 1824812

I was able to narrow down this apparmor_parser error to shiftfs:

AppArmor parser error for /etc/apparmor.d/sbin.dhclient in /etc/apparmor.d/tunables/home at line 25: Could not process include directory '/etc/apparmor.d/tunables/home.d' in 'tunables/home.d'

The problem stems from shiftfs not handling this sequence:

 getdents()
  lseek() to reset the f_pos to 0
   getdents()

I'm attaching a test case for this issue, called dir-seek.c.

When ran on a non-shiftfs filesystem, you'll see something like this:

 $ ./dir-seek
 PASS: orig_count (29) == new_count (29)

When you run the test case on shiftfs, you'll see something like this:

 $ ./dir-seek
 FAIL: orig_count (29) != new_count (0)

The f_pos of the directory file is not properly tracked/reset on shiftfs.