1 files changed, 19 insertions, 7 deletions

diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index 00b572666cc7..0a43def6fee7 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -30,6 +30,15 @@ fetch_robust_entry(compat_uptr_t *uentry, struct robust_list __user **entry,
         return 0;
 }
 
+static void __user *futex_uaddr(struct robust_list *entry,
+                                compat_long_t futex_offset)
+{
+        compat_uptr_t base = ptr_to_compat(entry);
+        void __user *uaddr = compat_ptr(base + futex_offset);
+
+        return uaddr;
+}
+
 /*
  * Walk curr->robust_list (very carefully, it's a userspace list!)
  * and mark any locks found there dead, and notify any waiters.
@@ -76,11 +85,12 @@ void compat_exit_robust_list(struct task_struct *curr)
                  * A pending lock might already be on the list, so
                  * dont process it twice:
                  */
-                if (entry != pending)
-                        if (handle_futex_death((void __user *)entry + futex_offset,
-                                                curr, pi))
-                                return;
+                if (entry != pending) {
+                        void __user *uaddr = futex_uaddr(entry, futex_offset);
 
+                        if (handle_futex_death(uaddr, curr, pi))
+                                return;
+                }
                 if (rc)
                         return;
                 uentry = next_uentry;
@@ -94,9 +104,11 @@ void compat_exit_robust_list(struct task_struct *curr)
 
                 cond_resched();
         }
-        if (pending)
-                handle_futex_death((void __user *)pending + futex_offset,
-                                   curr, pip);
+        if (pending) {
+                void __user *uaddr = futex_uaddr(pending, futex_offset);
+
+                handle_futex_death(uaddr, curr, pip);
+        }
 }
 
 asmlinkage long