1 files changed, 8 insertions, 2 deletions

diff --git a/include/asm-parisc/futex.h b/include/asm-parisc/futex.h
index dbee6e60aa81..fdc6d055ef7f 100644
--- a/include/asm-parisc/futex.h
+++ b/include/asm-parisc/futex.h
@@ -56,6 +56,12 @@ futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
         int err = 0;
         int uval;
 
+        /* futex.c wants to do a cmpxchg_inatomic on kernel NULL, which is
+         * our gateway page, and causes no end of trouble...
+         */
+        if (segment_eq(KERNEL_DS, get_fs()) && !uaddr)
+                return -EFAULT;
+
         if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
                 return -EFAULT;
 
@@ -67,5 +73,5 @@ futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
         return uval;
 }
 
-#endif
-#endif
+#endif /*__KERNEL__*/
+#endif /*_ASM_PARISC_FUTEX_H*/