add overflow tests

Author: Freax13

src/addr.rs

@@ -824,4 +824,16 @@ mod tests {
             VirtAddr::new(0)
         );
     }
+
+    #[test]
+    #[should_panic]
+    fn test_virt_addr_align_up_overflow() {
+        VirtAddr::new(0xffff_ffff_ffff_ffff).align_up(2u64);
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_phys_addr_align_up_overflow() {
+        PhysAddr::new(0x000f_ffff_ffff_ffff).align_up(2u64);
+    }
 }