diff --git a/net/sysctl_net.c b/net/sysctl_net.c
index 9aed6fe..d14dab8 100644
--- a/net/sysctl_net.c
+++ b/net/sysctl_net.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /* -*- linux-c -*-
  * sysctl_net.c: sysctl interface to net subsystem.
  *