diff --git a/kernel/src/heap.rs b/kernel/src/heap.rs
index 2b1de30..10b7710 100644
--- a/kernel/src/heap.rs
+++ b/kernel/src/heap.rs
@@ -22,7 +22,7 @@ impl Region {
 
     fn contains(&self, address: usize) -> bool {
         let start = self.start.load(Ordering::Relaxed);
-        let end = self.start.load(Ordering::Relaxed);
+        let end = start + self.size.load(Ordering::Relaxed);
         (start..start + end).contains(&address)
     }