diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 5fc3a9d..c45eb78d 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -1138,7 +1138,7 @@ int ip6_mc_source(int add, int omode, struct sock *sk,
 		  struct group_source_req *pgsr);
 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
-		  struct group_filter __user *optval, int __user *optlen);
+		  struct sockaddr_storage __user *p);
 
 #ifdef CONFIG_PROC_FS
 int ac6_proc_init(struct net *net);