Merge remote-tracking branch 'stable/linux-3.0.y' into android-3.0

[firefly-linux-kernel-4.4.55.git] / kernel / futex.c

diff --git a/kernel/futex.c b/kernel/futex.c
index b2d51a7ede3b30c8f4f5bfbcb544ba1085d32534..e45efe79dcb4d651018ef6755eb9446a0d05ad66 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2231,11 +2231,11 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
  * @uaddr2:    the pi futex we will take prior to returning to user-space
  *
  * The caller will wait on uaddr and will be requeued by futex_requeue() to
- * uaddr2 which must be PI aware.  Normal wakeup will wake on uaddr2 and
- * complete the acquisition of the rt_mutex prior to returning to userspace.
- * This ensures the rt_mutex maintains an owner when it has waiters; without
- * one, the pi logic wouldn't know which task to boost/deboost, if there was a
- * need to.
+ * uaddr2 which must be PI aware and unique from uaddr.  Normal wakeup will wake
+ * on uaddr2 and complete the acquisition of the rt_mutex prior to returning to
+ * userspace.  This ensures the rt_mutex maintains an owner when it has waiters;
+ * without one, the pi logic would not know which task to boost/deboost, if
+ * there was a need to.
  *
  * We call schedule in futex_wait_queue_me() when we enqueue and return there
  * via the following:
@@ -2272,6 +2272,9 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
        struct futex_q q = futex_q_init;
        int res, ret;
 
+       if (uaddr == uaddr2)
+               return -EINVAL;
+
        if (!bitset)
                return -EINVAL;
 
@@ -2343,7 +2346,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
                 * signal.  futex_unlock_pi() will not destroy the lock_ptr nor
                 * the pi_state.
                 */
-               WARN_ON(!&q.pi_state);
+               WARN_ON(!q.pi_state);
                pi_mutex = &q.pi_state->pi_mutex;
                ret = rt_mutex_finish_proxy_lock(pi_mutex, to, &rt_waiter, 1);
                debug_rt_mutex_free_waiter(&rt_waiter);
@@ -2370,7 +2373,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
         * fault, unlock the rt_mutex and return the fault to userspace.
         */
        if (ret == -EFAULT) {
-               if (rt_mutex_owner(pi_mutex) == current)
+               if (pi_mutex && rt_mutex_owner(pi_mutex) == current)
                        rt_mutex_unlock(pi_mutex);
        } else if (ret == -EINTR) {
                /*