diff --git a/mm/mempool/mempool.c b/mm/mempool/mempool.c
index 624ce291cb..89b3f80e24 100644
--- a/mm/mempool/mempool.c
+++ b/mm/mempool/mempool.c
@@ -397,16 +397,17 @@ retry:
 
   pool->nalloc++;
   spin_unlock_irqrestore(&pool->lock, flags);
-  blk = kasan_unpoison(blk, pool->blocksize);
-#ifdef CONFIG_MM_FILL_ALLOCATIONS
-  memset(blk, MM_ALLOC_MAGIC, pool->blocksize);
-#endif
 
 #if CONFIG_MM_BACKTRACE >= 0
   mempool_add_backtrace(pool, (FAR struct mempool_backtrace_s *)
                               ((FAR char *)blk + pool->blocksize));
 #endif
 
+  blk = kasan_unpoison(blk, pool->blocksize);
+#ifdef CONFIG_MM_FILL_ALLOCATIONS
+  memset(blk, MM_ALLOC_MAGIC, pool->blocksize);
+#endif
+
   return blk;
 }