diff --git a/fs/mmap/fs_munmap.c b/fs/mmap/fs_munmap.c
index 41f25a43b3..ac7daf8e6a 100644
--- a/fs/mmap/fs_munmap.c
+++ b/fs/mmap/fs_munmap.c
@@ -60,22 +60,27 @@ static int file_munmap_(FAR void *start, size_t length, bool kernel)
   ret = mm_map_lock();
   if (ret == OK)
     {
-      while (ret == OK && (entry = mm_map_find(mm, start, length)))
+      entry = mm_map_find(mm, start, length);
+
+      /* If entry don't find, the start and length is invalid. */
+
+      if (entry == NULL)
+        {
+          ret = -EINVAL;
+          goto unlock;
+        }
+
+      do
         {
           DEBUGASSERT(entry->munmap);
           ret = entry->munmap(group, entry, start, length);
         }
+      while (ret == OK && (entry = mm_map_find(mm, start, length)));
 
+unlock:
       mm_map_unlock();
     }
 
-  /* If entry don't find, the start and length is invalid. */
-
-  if (entry == NULL)
-    {
-      return -EINVAL;
-    }
-
   return ret;
 }