diff --git a/src/hole.rs b/src/hole.rs
index 5c25649..a095338 100644
--- a/src/hole.rs
+++ b/src/hole.rs
@@ -435,6 +435,11 @@ impl Cursor {
 
             // If we have a next, does the node overlap next?
             if let Some(next) = self.current().next.as_ref() {
+                if next < &node {
+                    // advance the list more
+                    return Err(());
+                }
+
                 let node_u8 = node_u8 as *const u8;
                 assert!(
                     node_u8.wrapping_add(node_size) <= next.as_ptr().cast::<u8>(),
diff --git a/src/test.rs b/src/test.rs
index f61bc10..5718410 100644
--- a/src/test.rs
+++ b/src/test.rs
@@ -151,9 +151,10 @@ fn deallocate_middle() {
         heap.deallocate(z, layout.clone());
         assert_eq!((*(x.as_ptr() as *const Hole)).size, size);
         assert_eq!((*(z.as_ptr() as *const Hole)).size, size);
-        heap.deallocate(y, layout.clone());
-        assert_eq!((*(x.as_ptr() as *const Hole)).size, size * 3);
         heap.deallocate(a, layout.clone());
+        assert_eq!((*(x.as_ptr() as *const Hole)).size, size);
+        assert_eq!((*(z.as_ptr() as *const Hole)).size, heap.size - 2 * size);
+        heap.deallocate(y, layout.clone());
         assert_eq!((*(x.as_ptr() as *const Hole)).size, heap.size);
     }
 }