Merge pull request moby#47498 from Dzejrou/lower-perm-fix

daemon: overlay2: remove world writable permission from the lower file

daemon/graphdriver/overlay2/overlay.go

@@ -406,7 +406,7 @@ func (d *Driver) create(id, parent string, opts *graphdriver.CreateOpts) (retErr
 		return err
 	}
 	if lower != "" {
-		if err := ioutils.AtomicWriteFile(path.Join(dir, lowerFile), []byte(lower), 0o666); err != nil {
+		if err := ioutils.AtomicWriteFile(path.Join(dir, lowerFile), []byte(lower), 0o644); err != nil {
 			return err
 		}
 	}