diff --git a/mm/tlsf/mm_tlsf.c b/mm/tlsf/mm_tlsf.c
index 25040a7e72a..eb966254299 100644
--- a/mm/tlsf/mm_tlsf.c
+++ b/mm/tlsf/mm_tlsf.c
@@ -681,7 +681,7 @@ void mm_addregion(FAR struct mm_heap_s *heap, FAR void *heapstart,
 #ifdef CONFIG_MM_FILL_ALLOCATIONS
   /* Use the fill value to mark uninitialized user memory */
 
-  memset(heapstart, 0xcc, heapsize);
+  memset(heapstart, MM_INIT_MAGIC, heapsize);
 #endif
 
   /* Register to KASan for access check */
@@ -1362,7 +1362,7 @@ FAR void *mm_malloc(FAR struct mm_heap_s *heap, size_t size)
       ret = kasan_unpoison(ret, nodesize);
 
 #ifdef CONFIG_MM_FILL_ALLOCATIONS
-      memset(ret, 0xaa, nodesize);
+      memset(ret, MM_ALLOC_MAGIC, nodesize);
 #endif
     }