diff --git a/net/ipv6/ip6_checksum.c b/net/ipv6/ip6_checksum.c
index c0cbcb2..ec43d18 100644
--- a/net/ipv6/ip6_checksum.c
+++ b/net/ipv6/ip6_checksum.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <net/ip.h>
 #include <net/udp.h>
 #include <net/udplite.h>