diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 1694845526be..b4eababc8198 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -443,7 +443,7 @@ asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
 	struct mempolicy *new;
 	DECLARE_BITMAP(nodes, MAX_NUMNODES);
 
-	if (mode > MPOL_MAX)
+	if (mode < 0 || mode > MPOL_MAX)
 		return -EINVAL;
 	err = get_nodes(nodes, nmask, maxnode, mode);
 	if (err)