net: sctp should update its inuse counter

This patch is a preparation to namespace conversion of /proc/net/protocols

In order to have relevant information for SCTP protocols, we should use
sock_prot_inuse_add() to update a (percpu and pernamespace) counter of
inuse sockets.
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sctp/socket.c

@@ -3614,6 +3614,7 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk)
 
 	SCTP_DBG_OBJCNT_INC(sock);
 	atomic_inc(&sctp_sockets_allocated);
+	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 	return 0;
 }
 
@@ -3628,6 +3629,7 @@ SCTP_STATIC void sctp_destroy_sock(struct sock *sk)
 	ep = sctp_sk(sk)->ep;
 	sctp_endpoint_free(ep);
 	atomic_dec(&sctp_sockets_allocated);
+	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 }
 
 /* API 4.1.7 shutdown() - TCP Style Syntax