diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 678bb95..af597c7 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -558,7 +558,7 @@
 	.hdr_offset	= xfrm6_find_1stfragopt,
 };
 
-static struct inet6_protocol esp6_protocol = {
+static const struct inet6_protocol esp6_protocol = {
 	.handler 	=	xfrm6_rcv,
 	.err_handler	=	esp6_err,
 	.flags		=	INET6_PROTO_NOPOLICY,