net-sctp: replace some sock_net(sk) with just 'net'

It already existed in part of the function, but move it
to a higher level and use it consistently throughout.

Safe since sk is never written to.
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sctp/socket.c

@@ -8267,6 +8267,7 @@ static int sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
 	struct sctp_sock *sp = sctp_sk(sk);
 	bool reuse = (sk->sk_reuse || sp->reuse);
 	struct sctp_bind_hashbucket *head; /* hash list */
+	struct net *net = sock_net(sk);
 	kuid_t uid = sock_i_uid(sk);
 	struct sctp_bind_bucket *pp;
 	unsigned short snum;
@@ -8282,7 +8283,6 @@ static int sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
 		/* Search for an available port. */
 		int low, high, remaining, index;
 		unsigned int rover;
-		struct net *net = sock_net(sk);
 
 		inet_get_local_port_range(net, &low, &high);
 		remaining = (high - low) + 1;
@@ -8294,12 +8294,12 @@ static int sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
 				rover = low;
 			if (inet_is_local_reserved_port(net, rover))
 				continue;
-			index = sctp_phashfn(sock_net(sk), rover);
+			index = sctp_phashfn(net, rover);
 			head = &sctp_port_hashtable[index];
 			spin_lock(&head->lock);
 			sctp_for_each_hentry(pp, &head->chain)
 				if ((pp->port == rover) &&
-				    net_eq(sock_net(sk), pp->net))
+				    net_eq(net, pp->net))
 					goto next;
 			break;
 		next:
@@ -8323,10 +8323,10 @@ static int sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
 		 * to the port number (snum) - we detect that with the
 		 * port iterator, pp being NULL.
 		 */
-		head = &sctp_port_hashtable[sctp_phashfn(sock_net(sk), snum)];
+		head = &sctp_port_hashtable[sctp_phashfn(net, snum)];
 		spin_lock(&head->lock);
 		sctp_for_each_hentry(pp, &head->chain) {
-			if ((pp->port == snum) && net_eq(pp->net, sock_net(sk)))
+			if ((pp->port == snum) && net_eq(pp->net, net))
 				goto pp_found;
 		}
 	}
@@ -8382,7 +8382,7 @@ static int sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
 pp_not_found:
 	/* If there was a hash table miss, create a new port.  */
 	ret = 1;
-	if (!pp && !(pp = sctp_bucket_create(head, sock_net(sk), snum)))
+	if (!pp && !(pp = sctp_bucket_create(head, net, snum)))
 		goto fail_unlock;
 
 	/* In either case (hit or miss), make sure fastreuse is 1 only