diff --git a/src/dired.c b/src/dired.c
index c446223a0b..ed12fce5f8 100644
--- a/src/dired.c
+++ b/src/dired.c
@@ -814,9 +814,9 @@ static bool
 file_name_completion_dirp (int fd, struct dirent *dp, ptrdiff_t len)
 {
   USE_SAFE_ALLOCA;
-  char *subdir_name = SAFE_ALLOCA (len + 2);
+  char *subdir_name = SAFE_ALLOCA (len + 4);
   memcpy (subdir_name, dp->d_name, len);
-  strcpy (subdir_name + len, "/");
+  strcpy (subdir_name + len, "/./");
   bool dirp = faccessat (fd, subdir_name, F_OK, AT_EACCESS) == 0;
   SAFE_FREE ();
   return dirp;