Index: sys/vm/vm_map.c
===================================================================
--- sys/vm/vm_map.c
+++ sys/vm/vm_map.c
@@ -1107,6 +1107,12 @@
 	boolean_t locked;
 
 	/*
+	 * If the address is out of range, fail immediately.
+	 */
+	if (address < map->min_offset || address >= map->max_offset)
+		return (FALSE);
+
+	/*
 	 * If the map is empty, then the map entry immediately preceding
 	 * "address" is the map's header.
 	 */