sctp: Make the ctl_sock per network namespace

- Kill sctp_get_ctl_sock, it is useless now.
- Pass struct net where needed so net->sctp.ctl_sock is accessible.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/netns/sctp.h

 #ifndef __NETNS_SCTP_H__
 #define __NETNS_SCTP_H__
 
+struct sock;
+
 struct netns_sctp {
+	/* This is the global socket data structure used for responding to
+	 * the Out-of-the-blue (OOTB) packets.  A control sock will be created
+	 * for this socket at the initialization time.
+	 */
+	struct sock *ctl_sock;
+
 	/* This is the global local address list.
 	 * We actively maintain this complete list of addresses on
 	 * the system by catching address add/delete events.

include/net/sctp/sctp.h

@@ -114,7 +114,6 @@
 /*
  * sctp/protocol.c
  */
-extern struct sock *sctp_get_ctl_sock(void);
 extern int sctp_copy_local_addr_list(struct net *, struct sctp_bind_addr *,
 				     sctp_scope_t, gfp_t gfp,
 				     int flags);

net/sctp/input.c

@@ -204,7 +204,7 @@ int sctp_rcv(struct sk_buff *skb)
 			sctp_endpoint_put(ep);
 			ep = NULL;
 		}
-		sk = sctp_get_ctl_sock();
+		sk = net->sctp.ctl_sock;
 		ep = sctp_sk(sk)->ep;
 		sctp_endpoint_hold(ep);
 		rcvr = &ep->base;
@@ -795,7 +795,7 @@ static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(struct net *net,
 			goto hit;
 	}
 
-	ep = sctp_sk((sctp_get_ctl_sock()))->ep;
+	ep = sctp_sk(net->sctp.ctl_sock)->ep;
 
 hit:
 	sctp_endpoint_hold(ep);

net/sctp/protocol.c

@@ -78,12 +78,6 @@ struct proc_dir_entry	*proc_net_sctp;
 struct idr sctp_assocs_id;
 DEFINE_SPINLOCK(sctp_assocs_id_lock);
 
-/* This is the global socket data structure used for responding to
- * the Out-of-the-blue (OOTB) packets.  A control sock will be created
- * for this socket at the initialization time.
- */
-static struct sock *sctp_ctl_sock;
-
 static struct sctp_pf *sctp_pf_inet6_specific;
 static struct sctp_pf *sctp_pf_inet_specific;
 static struct sctp_af *sctp_af_v4_specific;
@@ -96,12 +90,6 @@ long sysctl_sctp_mem[3];
 int sysctl_sctp_rmem[3];
 int sysctl_sctp_wmem[3];
 
-/* Return the address of the control sock. */
-struct sock *sctp_get_ctl_sock(void)
-{
-	return sctp_ctl_sock;
-}
-
 /* Set up the proc fs entry for the SCTP protocol. */
 static __init int sctp_proc_init(void)
 {
@@ -822,7 +810,7 @@ static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
  * Initialize the control inode/socket with a control endpoint data
  * structure.  This endpoint is reserved exclusively for the OOTB processing.
  */
-static int sctp_ctl_sock_init(void)
+static int sctp_ctl_sock_init(struct net *net)
 {
 	int err;
 	sa_family_t family = PF_INET;
@@ -830,14 +818,14 @@ static int sctp_ctl_sock_init(void)
 	if (sctp_get_pf_specific(PF_INET6))
 		family = PF_INET6;
 
-	err = inet_ctl_sock_create(&sctp_ctl_sock, family,
-				   SOCK_SEQPACKET, IPPROTO_SCTP, &init_net);
+	err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
+				   SOCK_SEQPACKET, IPPROTO_SCTP, net);
 
 	/* If IPv6 socket could not be created, try the IPv4 socket */
 	if (err < 0 && family == PF_INET6)
-		err = inet_ctl_sock_create(&sctp_ctl_sock, AF_INET,
+		err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
 					   SOCK_SEQPACKET, IPPROTO_SCTP,
-					   &init_net);
+					   net);
 
 	if (err < 0) {
 		pr_err("Failed to create the SCTP control socket\n");
@@ -1196,6 +1184,14 @@ static void sctp_v4_del_protocol(void)
 
 static int sctp_net_init(struct net *net)
 {
+	int status;
+
+	/* Initialize the control inode/socket for handling OOTB packets.  */
+	if ((status = sctp_ctl_sock_init(net))) {
+		pr_err("Failed to initialize the SCTP control sock\n");
+		goto err_ctl_sock_init;
+	}
+
 	/* Initialize the local address list. */
 	INIT_LIST_HEAD(&net->sctp.local_addr_list);
 	spin_lock_init(&net->sctp.local_addr_lock);
@@ -1210,6 +1206,9 @@ static int sctp_net_init(struct net *net)
 		    (unsigned long)net);
 
 	return 0;
+
+err_ctl_sock_init:
+	return status;
 }
 
 static void sctp_net_exit(struct net *net)
@@ -1217,6 +1216,9 @@ static void sctp_net_exit(struct net *net)
 	/* Free the local address list */
 	sctp_free_addr_wq(net);
 	sctp_free_local_addr_list(net);
+
+	/* Free the control endpoint.  */
+	inet_ctl_sock_destroy(net->sctp.ctl_sock);
 }
 
 static struct pernet_operations sctp_net_ops = {
@@ -1438,12 +1440,6 @@ SCTP_STATIC __init int sctp_init(void)
 	if (status)
 		goto err_v6_protosw_init;
 
-	/* Initialize the control inode/socket for handling OOTB packets.  */
-	if ((status = sctp_ctl_sock_init())) {
-		pr_err("Failed to initialize the SCTP control sock\n");
-		goto err_ctl_sock_init;
-	}
-
 	status = register_pernet_subsys(&sctp_net_ops);
 	if (status)
 		goto err_register_pernet_subsys;
@@ -1465,8 +1461,6 @@ SCTP_STATIC __init int sctp_init(void)
 err_add_protocol:
 	unregister_pernet_subsys(&sctp_net_ops);
 err_register_pernet_subsys:
-	inet_ctl_sock_destroy(sctp_ctl_sock);
-err_ctl_sock_init:
 	sctp_v6_protosw_exit();
 err_v6_protosw_init:
 	sctp_v4_protosw_exit();
@@ -1506,9 +1500,6 @@ SCTP_STATIC __exit void sctp_exit(void)
 	sctp_v6_del_protocol();
 	sctp_v4_del_protocol();
 
-	/* Free the control endpoint.  */
-	inet_ctl_sock_destroy(sctp_ctl_sock);
-
 	unregister_pernet_subsys(&sctp_net_ops);
 
 	/* Free protosw registrations */

net/sctp/sm_statefuns.c

@@ -74,7 +74,8 @@ static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep,
 static int sctp_eat_data(const struct sctp_association *asoc,
 			 struct sctp_chunk *chunk,
 			 sctp_cmd_seq_t *commands);
-static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc,
+static struct sctp_packet *sctp_ootb_pkt_new(struct net *net,
+					     const struct sctp_association *asoc,
 					     const struct sctp_chunk *chunk);
 static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep,
 				       const struct sctp_association *asoc,
@@ -301,6 +302,7 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
 	struct sctp_chunk *err_chunk;
 	struct sctp_packet *packet;
 	sctp_unrecognized_param_t *unk_param;
+	struct net *net;
 	int len;
 
 	/* 6.10 Bundling
@@ -318,7 +320,8 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
 	/* If the packet is an OOTB packet which is temporarily on the
 	 * control endpoint, respond with an ABORT.
 	 */
-	if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) {
+	net = sock_net(ep->base.sk);
+	if (ep == sctp_sk(net->sctp.ctl_sock)->ep) {
 		SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES);
 		return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands);
 	}
@@ -646,11 +649,13 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,
 	int error = 0;
 	struct sctp_chunk *err_chk_p;
 	struct sock *sk;
+	struct net *net;
 
 	/* If the packet is an OOTB packet which is temporarily on the
 	 * control endpoint, respond with an ABORT.
 	 */
-	if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) {
+	net = sock_net(ep->base.sk);
+	if (ep == sctp_sk(net->sctp.ctl_sock)->ep) {
 		SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES);
 		return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands);
 	}
@@ -1171,7 +1176,7 @@ sctp_disposition_t sctp_sf_backbeat_8_3(const struct sctp_endpoint *ep,
 /* Helper function to send out an abort for the restart
  * condition.
  */
-static int sctp_sf_send_restart_abort(union sctp_addr *ssa,
+static int sctp_sf_send_restart_abort(struct net *net, union sctp_addr *ssa,
 				      struct sctp_chunk *init,
 				      sctp_cmd_seq_t *commands)
 {
@@ -1197,7 +1202,7 @@ static int sctp_sf_send_restart_abort(union sctp_addr *ssa,
 	errhdr->length = htons(len);
 
 	/* Assign to the control socket. */
-	ep = sctp_sk((sctp_get_ctl_sock()))->ep;
+	ep = sctp_sk(net->sctp.ctl_sock)->ep;
 
 	/* Association is NULL since this may be a restart attack and we
 	 * want to send back the attacker's vtag.
@@ -1240,6 +1245,7 @@ static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc,
 				       struct sctp_chunk *init,
 				       sctp_cmd_seq_t *commands)
 {
+	struct net *net = sock_net(new_asoc->base.sk);
 	struct sctp_transport *new_addr;
 	int ret = 1;
 
@@ -1258,7 +1264,7 @@ static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc,
 			    transports) {
 		if (!list_has_sctp_addr(&asoc->peer.transport_addr_list,
 					&new_addr->ipaddr)) {
-			sctp_sf_send_restart_abort(&new_addr->ipaddr, init,
+			sctp_sf_send_restart_abort(net, &new_addr->ipaddr, init,
 						   commands);
 			ret = 0;
 			break;
@@ -1650,10 +1656,11 @@ sctp_disposition_t sctp_sf_do_5_2_3_initack(const struct sctp_endpoint *ep,
 					    const sctp_subtype_t type,
 					    void *arg, sctp_cmd_seq_t *commands)
 {
+	struct net *net = sock_net(ep->base.sk);
 	/* Per the above section, we'll discard the chunk if we have an
 	 * endpoint.  If this is an OOTB INIT-ACK, treat it as such.
 	 */
-	if (ep == sctp_sk((sctp_get_ctl_sock()))->ep)
+	if (ep == sctp_sk(net->sctp.ctl_sock)->ep)
 		return sctp_sf_ootb(ep, asoc, type, arg, commands);
 	else
 		return sctp_sf_discard_chunk(ep, asoc, type, arg, commands);
@@ -3163,8 +3170,10 @@ static sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep,
 	struct sctp_packet *packet = NULL;
 	struct sctp_chunk *chunk = arg;
 	struct sctp_chunk *abort;
+	struct net *net;
 
-	packet = sctp_ootb_pkt_new(asoc, chunk);
+	net = sock_net(ep->base.sk);
+	packet = sctp_ootb_pkt_new(net, asoc, chunk);
 
 	if (packet) {
 		/* Make an ABORT. The T bit will be set if the asoc
@@ -3425,8 +3434,10 @@ static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep,
 	struct sctp_packet *packet = NULL;
 	struct sctp_chunk *chunk = arg;
 	struct sctp_chunk *shut;
+	struct net *net;
 
-	packet = sctp_ootb_pkt_new(asoc, chunk);
+	net = sock_net(ep->base.sk);
+	packet = sctp_ootb_pkt_new(net, asoc, chunk);
 
 	if (packet) {
 		/* Make an SHUTDOWN_COMPLETE.
@@ -4262,6 +4273,7 @@ static sctp_disposition_t sctp_sf_abort_violation(
 	struct sctp_packet *packet = NULL;
 	struct sctp_chunk *chunk =  arg;
 	struct sctp_chunk *abort = NULL;
+	struct net *net;
 
 	/* SCTP-AUTH, Section 6.3:
 	 *    It should be noted that if the receiver wants to tear
@@ -4282,6 +4294,7 @@ static sctp_disposition_t sctp_sf_abort_violation(
 	if (!abort)
 		goto nomem;
 
+	net = sock_net(ep->base.sk);
 	if (asoc) {
 		/* Treat INIT-ACK as a special case during COOKIE-WAIT. */
 		if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK &&
@@ -4319,7 +4332,7 @@ static sctp_disposition_t sctp_sf_abort_violation(
 			SCTP_DEC_STATS(SCTP_MIB_CURRESTAB);
 		}
 	} else {
-		packet = sctp_ootb_pkt_new(asoc, chunk);
+		packet = sctp_ootb_pkt_new(net, asoc, chunk);
 
 		if (!packet)
 			goto nomem_pkt;
@@ -5825,8 +5838,10 @@ static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep,
 {
 	struct sctp_packet *packet;
 	struct sctp_chunk *abort;
+	struct net *net;
 
-	packet = sctp_ootb_pkt_new(asoc, chunk);
+	net = sock_net(ep->base.sk);
+	packet = sctp_ootb_pkt_new(net, asoc, chunk);
 
 	if (packet) {
 		/* Make an ABORT.
@@ -5858,7 +5873,8 @@ static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep,
 }
 
 /* Allocate a packet for responding in the OOTB conditions.  */
-static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc,
+static struct sctp_packet *sctp_ootb_pkt_new(struct net *net,
+					     const struct sctp_association *asoc,
 					     const struct sctp_chunk *chunk)
 {
 	struct sctp_packet *packet;
@@ -5919,7 +5935,7 @@ static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc
 	 * the source address.
 	 */
 	sctp_transport_route(transport, (union sctp_addr *)&chunk->dest,
-			     sctp_sk(sctp_get_ctl_sock()));
+			     sctp_sk(net->sctp.ctl_sock));
 
 	packet = sctp_packet_init(&transport->packet, transport, sport, dport);
 	packet = sctp_packet_config(packet, vtag, 0);
@@ -5946,7 +5962,8 @@ static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep,
 	struct sctp_packet *packet;
 
 	if (err_chunk) {
-		packet = sctp_ootb_pkt_new(asoc, chunk);
+		struct net *net = sock_net(ep->base.sk);
+		packet = sctp_ootb_pkt_new(net, asoc, chunk);
 		if (packet) {
 			struct sctp_signed_cookie *cookie;