commit c2e3f5d5 upstream.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[ luis: 3.16-stable, just to make 6d65261a ("eCryptfs: don't pass
  fs-specific ioctl commands through") a clean cherry-pick ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>