From: "Serge E. Hallyn" <serue@us.ibm.com>

Don't do user_ns permission checks when !CONFIG_USER_NS.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 include/linux/sched.h |    8 ++++++++
 1 file changed, 8 insertions(+)

diff -puN include/linux/sched.h~user-ns-add-user_namespace-ptr-to-vfsmount-fixes include/linux/sched.h
--- a/include/linux/sched.h~user-ns-add-user_namespace-ptr-to-vfsmount-fixes
+++ a/include/linux/sched.h
@@ -1598,6 +1598,7 @@ extern int cond_resched(void);
 extern int cond_resched_lock(spinlock_t * lock);
 extern int cond_resched_softirq(void);
 
+#ifdef CONFIG_USER_NS
 /*
  * Check whether a task and a vfsmnt belong to the same uidns.
  * Since the initial namespace is exempt from these checks,
@@ -1614,6 +1615,13 @@ static inline int task_mnt_same_uidns(st
 		return 1;
 	return 0;
 }
+#else
+static inline int task_mnt_same_uidns(struct task_struct *tsk,
+					struct vfsmount *mnt)
+{
+	return 1;
+}
+#endif
 
 
 /*
_