The function is now UDP-specific, the protocol is always IPPROTO_UDP.
This is similar to what already done for IPv4 in commit 
78f3655adcb5
("ipv4: remove "proto" argument from udp_tunnel_dst_lookup()").
Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
 
                return -ESHUTDOWN;
 
        dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock, &saddr, info,
-                                    IPPROTO_UDP, use_cache);
+                                    use_cache);
        if (IS_ERR(dst))
                return PTR_ERR(dst);
 
                struct socket *sock = rcu_dereference(bareudp->sock);
 
                dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock,
-                                            &saddr, info, IPPROTO_UDP,
-                                            use_cache);
+                                            &saddr, info, use_cache);
                if (IS_ERR(dst))
                        return PTR_ERR(dst);
 
 
                                         struct socket *sock,
                                         struct in6_addr *saddr,
                                         const struct ip_tunnel_info *info,
-                                        u8 protocol, bool use_cache);
+                                        bool use_cache);
 
 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
                                    __be16 flags, __be64 tunnel_id,
 
  *      @sock: Socket which provides route info
  *      @saddr: Memory to store the src ip address
  *      @info: Tunnel information
- *      @protocol: IP protocol
  *      @use_cache: Flag to enable cache usage
  *      This function performs a route lookup on a UDP tunnel
  *
                                         struct socket *sock,
                                         struct in6_addr *saddr,
                                         const struct ip_tunnel_info *info,
-                                        u8 protocol,
                                         bool use_cache)
 {
        struct dst_entry *dst = NULL;
 #endif
        memset(&fl6, 0, sizeof(fl6));
        fl6.flowi6_mark = skb->mark;
-       fl6.flowi6_proto = protocol;
+       fl6.flowi6_proto = IPPROTO_UDP;
        fl6.daddr = info->key.u.ipv6.dst;
        fl6.saddr = info->key.u.ipv6.src;
        prio = info->key.tos;