Merge r181069 from head to stable/7:

Merge r181069 from head to stable/7:

  In mac_bsdextended's auditctl and acct policy access control checks,
  return success if the passed vnode pointer is NULL (rather than
  panicking).  This can occur if either audit or accounting are
  disabled while the policy is running.

  Since the swapoff control has no real relevance to this policy,
  which is concerned about intent to write rather than water under the
  bridge, remove it.

  PR:             kern/126100
  Reported by:    Alan Amesbury <amesbury at umn dot edu>