static int sctp_getsockopt(struct sock *sk, int level, int optname,
			   char __user *optval, int __user *optlen)
{
	int retval = 0;
	int len;

	pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);

	/* I can hardly begin to describe how wrong this is.  This is
	 * so broken as to be worse than useless.  The API draft
	 * REALLY is NOT helpful here...  I am not convinced that the
	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
	 * are at all well-founded.
	 */
	if (level != SOL_SCTP) {
		struct sctp_af *af = sctp_sk(sk)->pf->af;

		retval = af->getsockopt(sk, level, optname, optval, optlen);
		return retval;
	}

	if (get_user(len, optlen))
		return -EFAULT;

	if (len < 0)
		return -EINVAL;

	lock_sock(sk);

	switch (optname) {
	case SCTP_STATUS:
		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
		break;
	case SCTP_DISABLE_FRAGMENTS:
		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
							   optlen);
		break;
	case SCTP_EVENTS:
		retval = sctp_getsockopt_events(sk, len, optval, optlen);
		break;
	case SCTP_AUTOCLOSE:
		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
		break;
	case SCTP_SOCKOPT_PEELOFF:
		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
		break;
	case SCTP_SOCKOPT_PEELOFF_FLAGS:
		retval = sctp_getsockopt_peeloff_flags(sk, len, optval, optlen);
		break;
	case SCTP_PEER_ADDR_PARAMS:
		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
							  optlen);
		break;
	case SCTP_DELAYED_SACK:
		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
							  optlen);
		break;
	case SCTP_INITMSG:
		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
		break;
	case SCTP_GET_PEER_ADDRS:
		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
						    optlen);
		break;
	case SCTP_GET_LOCAL_ADDRS:
		retval = sctp_getsockopt_local_addrs(sk, len, optval,
						     optlen);
		break;
	case SCTP_SOCKOPT_CONNECTX3:
		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
		break;
	case SCTP_DEFAULT_SEND_PARAM:
		retval = sctp_getsockopt_default_send_param(sk, len,
							    optval, optlen);
		break;
	case SCTP_DEFAULT_SNDINFO:
		retval = sctp_getsockopt_default_sndinfo(sk, len,
							 optval, optlen);
		break;
	case SCTP_PRIMARY_ADDR:
		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
		break;
	case SCTP_NODELAY:
		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
		break;
	case SCTP_RTOINFO:
		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
		break;
	case SCTP_ASSOCINFO:
		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
		break;
	case SCTP_I_WANT_MAPPED_V4_ADDR:
		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
		break;
	case SCTP_MAXSEG:
		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
		break;
	case SCTP_GET_PEER_ADDR_INFO:
		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
							optlen);
		break;
	case SCTP_ADAPTATION_LAYER:
		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
							optlen);
		break;
	case SCTP_CONTEXT:
		retval = sctp_getsockopt_context(sk, len, optval, optlen);
		break;
	case SCTP_FRAGMENT_INTERLEAVE:
		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
							     optlen);
		break;
	case SCTP_PARTIAL_DELIVERY_POINT:
		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
								optlen);
		break;
	case SCTP_MAX_BURST:
		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
		break;
	case SCTP_AUTH_KEY:
	case SCTP_AUTH_CHUNK:
	case SCTP_AUTH_DELETE_KEY:
	case SCTP_AUTH_DEACTIVATE_KEY:
		retval = -EOPNOTSUPP;
		break;
	case SCTP_HMAC_IDENT:
		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
		break;
	case SCTP_AUTH_ACTIVE_KEY:
		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
		break;
	case SCTP_PEER_AUTH_CHUNKS:
		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
							optlen);
		break;
	case SCTP_LOCAL_AUTH_CHUNKS:
		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
							optlen);
		break;
	case SCTP_GET_ASSOC_NUMBER:
		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
		break;
	case SCTP_GET_ASSOC_ID_LIST:
		retval = sctp_getsockopt_assoc_ids(sk, len, optval, optlen);
		break;
	case SCTP_AUTO_ASCONF:
		retval = sctp_getsockopt_auto_asconf(sk, len, optval, optlen);
		break;
	case SCTP_PEER_ADDR_THLDS:
		retval = sctp_getsockopt_paddr_thresholds(sk, optval, len,
							  optlen, false);
		break;
	case SCTP_PEER_ADDR_THLDS_V2:
		retval = sctp_getsockopt_paddr_thresholds(sk, optval, len,
							  optlen, true);
		break;
	case SCTP_GET_ASSOC_STATS:
		retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
		break;
	case SCTP_RECVRCVINFO:
		retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
		break;
	case SCTP_RECVNXTINFO:
		retval = sctp_getsockopt_recvnxtinfo(sk, len, optval, optlen);
		break;
	case SCTP_PR_SUPPORTED:
		retval = sctp_getsockopt_pr_supported(sk, len, optval, optlen);
		break;
	case SCTP_DEFAULT_PRINFO:
		retval = sctp_getsockopt_default_prinfo(sk, len, optval,
							optlen);
		break;
	case SCTP_PR_ASSOC_STATUS:
		retval = sctp_getsockopt_pr_assocstatus(sk, len, optval,
							optlen);
		break;
	case SCTP_PR_STREAM_STATUS:
		retval = sctp_getsockopt_pr_streamstatus(sk, len, optval,
							 optlen);
		break;
	case SCTP_RECONFIG_SUPPORTED:
		retval = sctp_getsockopt_reconfig_supported(sk, len, optval,
							    optlen);
		break;
	case SCTP_ENABLE_STREAM_RESET:
		retval = sctp_getsockopt_enable_strreset(sk, len, optval,
							 optlen);
		break;
	case SCTP_STREAM_SCHEDULER:
		retval = sctp_getsockopt_scheduler(sk, len, optval,
						   optlen);
		break;
	case SCTP_STREAM_SCHEDULER_VALUE:
		retval = sctp_getsockopt_scheduler_value(sk, len, optval,
							 optlen);
		break;
	case SCTP_INTERLEAVING_SUPPORTED:
		retval = sctp_getsockopt_interleaving_supported(sk, len, optval,
								optlen);
		break;
	case SCTP_REUSE_PORT:
		retval = sctp_getsockopt_reuse_port(sk, len, optval, optlen);
		break;
	case SCTP_EVENT:
		retval = sctp_getsockopt_event(sk, len, optval, optlen);
		break;
	case SCTP_ASCONF_SUPPORTED:
		retval = sctp_getsockopt_asconf_supported(sk, len, optval,
							  optlen);
		break;
	case SCTP_AUTH_SUPPORTED:
		retval = sctp_getsockopt_auth_supported(sk, len, optval,
							optlen);
		break;
	case SCTP_ECN_SUPPORTED:
		retval = sctp_getsockopt_ecn_supported(sk, len, optval, optlen);
		break;
	case SCTP_EXPOSE_POTENTIALLY_FAILED_STATE:
		retval = sctp_getsockopt_pf_expose(sk, len, optval, optlen);
		break;
	case SCTP_REMOTE_UDP_ENCAPS_PORT:
		retval = sctp_getsockopt_encap_port(sk, len, optval, optlen);
		break;
	default:
		retval = -ENOPROTOOPT;
		break;
	}

	release_sock(sk);
	return retval;
}

static bool sctp_writeable(struct sock *sk);

static void sctp_wfree(struct sk_buff *skb);

static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
				size_t msg_len);

static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);

static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);

static int sctp_wait_for_accept(struct sock *sk, long timeo);

static void sctp_wait_for_close(struct sock *sk, long timeo);

static void sctp_destruct_sock(struct sock *sk);

static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
					union sctp_addr *addr, int len);

static int sctp_bindx_add(struct sock *, struct sockaddr *, int);

static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf(struct sctp_association *asoc,
			    struct sctp_chunk *chunk);

static int sctp_do_bind(struct sock *, union sctp_addr *, int);

static int sctp_autobind(struct sock *sk);

static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
			     struct sctp_association *assoc,
			     enum sctp_socket_type type);

static unsigned long sctp_memory_pressure;

static atomic_long_t sctp_memory_allocated;

struct percpu_counter sctp_sockets_allocated;

static int sctp_get_port_local(struct sock *, union sctp_addr *);

struct compat_sctp_getaddrs_old {
	sctp_assoc_t	assoc_id;
	s32		addr_num;
	compat_uptr_t	addrs;		/* struct sockaddr * */
}

static int sctp_msghdr_parse(const struct msghdr *msg,
			     struct sctp_cmsgs *cmsgs);

static struct sctp_bind_bucket *sctp_bucket_create(
	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);

struct proto sctp_prot = {
	.name        =	"SCTP",
	.owner       =	THIS_MODULE,
	.close       =	sctp_close,
	.disconnect  =	sctp_disconnect,
	.accept      =	sctp_accept,
	.ioctl       =	sctp_ioctl,
	.init        =	sctp_init_sock,
	.destroy     =	sctp_destroy_sock,
	.shutdown    =	sctp_shutdown,
	.setsockopt  =	sctp_setsockopt,
	.getsockopt  =	sctp_getsockopt,
	.sendmsg     =	sctp_sendmsg,
	.recvmsg     =	sctp_recvmsg,
	.bind        =	sctp_bind,
	.bind_add    =  sctp_bind_add,
	.backlog_rcv =	sctp_backlog_rcv,
	.hash        =	sctp_hash,
	.unhash      =	sctp_unhash,
	.no_autobind =	true,
	.obj_size    =  sizeof(struct sctp_sock),
	.useroffset  =  offsetof(struct sctp_sock, subscribe),
	.usersize    =  offsetof(struct sctp_sock, initmsg) -
				offsetof(struct sctp_sock, subscribe) +
				sizeof_field(struct sctp_sock, initmsg),
	.sysctl_mem  =  sysctl_sctp_mem,
	.sysctl_rmem =  sysctl_sctp_rmem,
	.sysctl_wmem =  sysctl_sctp_wmem,
	.memory_pressure = &sctp_memory_pressure,
	.enter_memory_pressure = sctp_enter_memory_pressure,
	.memory_allocated = &sctp_memory_allocated,
	.sockets_allocated = &sctp_sockets_allocated,
};


static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
				       struct sctp_transport   *trans,
				       struct sctp_association *asoc,
				       struct sctp_sock        *sp,
				       int                      hb_change,
				       int                      pmtud_change,
				       int                      sackdelay_change)
{
	int error;

	if (params->spp_flags & SPP_HB_DEMAND && trans) {
		error = sctp_primitive_REQUESTHEARTBEAT(trans->asoc->base.net,
							trans->asoc, trans);
		if (error)
			return error;
	}

	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
	 * this field is ignored.  Note also that a value of zero indicates
	 * the current setting should be left unchanged.
	 */
	if (params->spp_flags & SPP_HB_ENABLE) {

		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
		 * set.  This lets us use 0 value when this flag
		 * is set.
		 */
		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
			params->spp_hbinterval = 0;

		if (params->spp_hbinterval ||
		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
			if (trans) {
				trans->hbinterval =
				    msecs_to_jiffies(params->spp_hbinterval);
			} else if (asoc) {
				asoc->hbinterval =
				    msecs_to_jiffies(params->spp_hbinterval);
			} else {
				sp->hbinterval = params->spp_hbinterval;
			}
		}
	}

	if (hb_change) {
		if (trans) {
			trans->param_flags =
				(trans->param_flags & ~SPP_HB) | hb_change;
		} else if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_HB) | hb_change;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_HB) | hb_change;
		}
	}

	/* When Path MTU discovery is disabled the value specified here will
	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
	 * include the flag SPP_PMTUD_DISABLE for this field to have any
	 * effect).
	 */
	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
		if (trans) {
			trans->pathmtu = params->spp_pathmtu;
			sctp_assoc_sync_pmtu(asoc);
		} else if (asoc) {
			sctp_assoc_set_pmtu(asoc, params->spp_pathmtu);
		} else {
			sp->pathmtu = params->spp_pathmtu;
		}
	}

	if (pmtud_change) {
		if (trans) {
			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
				(params->spp_flags & SPP_PMTUD_ENABLE);
			trans->param_flags =
				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
			if (update) {
				sctp_transport_pmtu(trans, sctp_opt2sk(sp));
				sctp_assoc_sync_pmtu(asoc);
			}
		} else if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
		}
	}

	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
	 * value of this field is ignored.  Note also that a value of zero
	 * indicates the current setting should be left unchanged.
	 */
	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
		if (trans) {
			trans->sackdelay =
				msecs_to_jiffies(params->spp_sackdelay);
		} else if (asoc) {
			asoc->sackdelay =
				msecs_to_jiffies(params->spp_sackdelay);
		} else {
			sp->sackdelay = params->spp_sackdelay;
		}
	}

	if (sackdelay_change) {
		if (trans) {
			trans->param_flags =
				(trans->param_flags & ~SPP_SACKDELAY) |
				sackdelay_change;
		} else if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_SACKDELAY) |
				sackdelay_change;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_SACKDELAY) |
				sackdelay_change;
		}
	}

	/* Note that a value of zero indicates the current setting should be
	   left unchanged.
	 */
	if (params->spp_pathmaxrxt) {
		if (trans) {
			trans->pathmaxrxt = params->spp_pathmaxrxt;
		} else if (asoc) {
			asoc->pathmaxrxt = params->spp_pathmaxrxt;
		} else {
			sp->pathmaxrxt = params->spp_pathmaxrxt;
		}
	}

	if (params->spp_flags & SPP_IPV6_FLOWLABEL) {
		if (trans) {
			if (trans->ipaddr.sa.sa_family == AF_INET6) {
				trans->flowlabel = params->spp_ipv6_flowlabel &
						   SCTP_FLOWLABEL_VAL_MASK;
				trans->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
			}
		} else if (asoc) {
			struct sctp_transport *t;

			list_for_each_entry(t, &asoc->peer.transport_addr_list,
					    transports) {
				if (t->ipaddr.sa.sa_family != AF_INET6)
					continue;
				t->flowlabel = params->spp_ipv6_flowlabel &
					       SCTP_FLOWLABEL_VAL_MASK;
				t->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
			}
			asoc->flowlabel = params->spp_ipv6_flowlabel &
					  SCTP_FLOWLABEL_VAL_MASK;
			asoc->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
		} else if (sctp_opt2sk(sp)->sk_family == AF_INET6) {
			sp->flowlabel = params->spp_ipv6_flowlabel &
					SCTP_FLOWLABEL_VAL_MASK;
			sp->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
		}
	}

	if (params->spp_flags & SPP_DSCP) {
		if (trans) {
			trans->dscp = params->spp_dscp & SCTP_DSCP_VAL_MASK;
			trans->dscp |= SCTP_DSCP_SET_MASK;
		} else if (asoc) {
			struct sctp_transport *t;

			list_for_each_entry(t, &asoc->peer.transport_addr_list,
					    transports) {
				t->dscp = params->spp_dscp &
					  SCTP_DSCP_VAL_MASK;
				t->dscp |= SCTP_DSCP_SET_MASK;
			}
			asoc->dscp = params->spp_dscp & SCTP_DSCP_VAL_MASK;
			asoc->dscp |= SCTP_DSCP_SET_MASK;
		} else {
			sp->dscp = params->spp_dscp & SCTP_DSCP_VAL_MASK;
			sp->dscp |= SCTP_DSCP_SET_MASK;
		}
	}

	return 0;
}

net/sctp: fix race condition in sctp_destroy_sock

If sctp_destroy_sock is called without sock_net(sk)->sctp.addr_wq_lock
held and sp->do_auto_asconf is true, then an element is removed
from the auto_asconf_splist without any proper locking.

This can happen in the following functions:
1. In sctp_accept, if sctp_sock_migrate fails.
2. In inet_create or inet6_create, if there is a bpf program
   attached to BPF_CGROUP_INET_SOCK_CREATE which denies
   creation of the sctp socket.

The bug is fixed by acquiring addr_wq_lock in sctp_destroy_sock
instead of sctp_close.

This addresses CVE-2021-23133.

Reported-by: Or Cohen <orcohen@paloaltonetworks.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Fixes: 610236587600 ("bpf: Add new cgroup attach type to enable sock modifications")
Signed-off-by: Or Cohen <orcohen@paloaltonetworks.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

static bool sctp_writeable(struct sock *sk);

static void sctp_wfree(struct sk_buff *skb);

static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
				size_t msg_len);

static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);

static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);

static int sctp_wait_for_accept(struct sock *sk, long timeo);

static void sctp_wait_for_close(struct sock *sk, long timeo);

static void sctp_destruct_sock(struct sock *sk);

static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
					union sctp_addr *addr, int len);

static int sctp_bindx_add(struct sock *, struct sockaddr *, int);

static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf(struct sctp_association *asoc,
			    struct sctp_chunk *chunk);

static int sctp_do_bind(struct sock *, union sctp_addr *, int);

static int sctp_autobind(struct sock *sk);

static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
			     struct sctp_association *assoc,
			     enum sctp_socket_type type);

static unsigned long sctp_memory_pressure;

static atomic_long_t sctp_memory_allocated;

struct percpu_counter sctp_sockets_allocated;

#define traverse_and_process()	\
do {				\
	msg = chunk->msg;	\
	if (msg == prev_msg)	\
		continue;	\
	list_for_each_entry(c, &msg->chunks, frag_list) {	\
		if ((clear && asoc->base.sk == c->skb->sk) ||	\
		    (!clear && asoc->base.sk != c->skb->sk))	\
			cb(c);	\
	}			\
	prev_msg = msg;		\
} while (0)

static int sctp_get_port_local(struct sock *, union sctp_addr *);

struct compat_sctp_getaddrs_old {
	sctp_assoc_t	assoc_id;
	s32		addr_num;
	compat_uptr_t	addrs;		/* struct sockaddr * */
}

static int sctp_msghdr_parse(const struct msghdr *msg,
			     struct sctp_cmsgs *cmsgs);

static struct sctp_bind_bucket *sctp_bucket_create(
	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);


int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *),
			    int (*cb_done)(struct sctp_transport *, void *),
			    struct net *net, int *pos, void *p) {
	struct rhashtable_iter hti;
	struct sctp_transport *tsp;
	int ret;

again:
	ret = 0;
	sctp_transport_walk_start(&hti);

	tsp = sctp_transport_get_idx(net, &hti, *pos + 1);
	for (; !IS_ERR_OR_NULL(tsp); tsp = sctp_transport_get_next(net, &hti)) {
		ret = cb(tsp, p);
		if (ret)
			break;
		(*pos)++;
		sctp_transport_put(tsp);
	}
	sctp_transport_walk_stop(&hti);

	if (ret) {
		if (cb_done && !cb_done(tsp, p)) {
			(*pos)++;
			sctp_transport_put(tsp);
			goto again;
		}
		sctp_transport_put(tsp);
	}

	return ret;
}

static bool sctp_writeable(struct sock *sk);

static void sctp_wfree(struct sk_buff *skb);

static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
				size_t msg_len);

static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);

static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);

static int sctp_wait_for_accept(struct sock *sk, long timeo);

static void sctp_wait_for_close(struct sock *sk, long timeo);

static void sctp_destruct_sock(struct sock *sk);

static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
					union sctp_addr *addr, int len);

static int sctp_bindx_add(struct sock *, struct sockaddr *, int);

static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf(struct sctp_association *asoc,
			    struct sctp_chunk *chunk);

static int sctp_do_bind(struct sock *, union sctp_addr *, int);

static int sctp_autobind(struct sock *sk);

static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
			     struct sctp_association *assoc,
			     enum sctp_socket_type type);

struct percpu_counter sctp_sockets_allocated;

static int sctp_get_port_local(struct sock *, union sctp_addr *);

struct compat_sctp_getaddrs_old {
	sctp_assoc_t	assoc_id;
	s32		addr_num;
	compat_uptr_t	addrs;		/* struct sockaddr * */
}

static int sctp_msghdr_parse(const struct msghdr *msg,
			     struct sctp_cmsgs *cmsgs);

static struct sctp_bind_bucket *sctp_bucket_create(
	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);

struct proto sctp_prot = {
	.name        =	"SCTP",
	.owner       =	THIS_MODULE,
	.close       =	sctp_close,
	.disconnect  =	sctp_disconnect,
	.accept      =	sctp_accept,
	.ioctl       =	sctp_ioctl,
	.init        =	sctp_init_sock,
	.destroy     =	sctp_destroy_sock,
	.shutdown    =	sctp_shutdown,
	.setsockopt  =	sctp_setsockopt,
	.getsockopt  =	sctp_getsockopt,
	.sendmsg     =	sctp_sendmsg,
	.recvmsg     =	sctp_recvmsg,
	.bind        =	sctp_bind,
	.bind_add    =  sctp_bind_add,
	.backlog_rcv =	sctp_backlog_rcv,
	.hash        =	sctp_hash,
	.unhash      =	sctp_unhash,
	.no_autobind =	true,
	.obj_size    =  sizeof(struct sctp_sock),
	.useroffset  =  offsetof(struct sctp_sock, subscribe),
	.usersize    =  offsetof(struct sctp_sock, initmsg) -
				offsetof(struct sctp_sock, subscribe) +
				sizeof_field(struct sctp_sock, initmsg),
	.sysctl_mem  =  sysctl_sctp_mem,
	.sysctl_rmem =  sysctl_sctp_rmem,
	.sysctl_wmem =  sysctl_sctp_wmem,
	.memory_pressure = &sctp_memory_pressure,
	.enter_memory_pressure = sctp_enter_memory_pressure,
	.memory_allocated = &sctp_memory_allocated,
	.sockets_allocated = &sctp_sockets_allocated,
};


static int sctp_setsockopt_pf_expose(struct sock *sk,
				     struct sctp_assoc_value *params,
				     unsigned int optlen)
{
	struct sctp_association *asoc;
	int retval = -EINVAL;

	if (optlen != sizeof(*params))
		goto out;

	if (params->assoc_value > SCTP_PF_EXPOSE_MAX)
		goto out;

	asoc = sctp_id2assoc(sk, params->assoc_id);
	if (!asoc && params->assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		goto out;

	if (asoc)
		asoc->pf_expose = params->assoc_value;
	else
		sctp_sk(sk)->pf_expose = params->assoc_value;
	retval = 0;

out:
	return retval;
}


static int sctp_getsockopt_maxburst(struct sock *sk, int len,
				    char __user *optval,
				    int __user *optlen)
{
	struct sctp_assoc_value params;
	struct sctp_association *asoc;

	if (len == sizeof(int)) {
		pr_warn_ratelimited(DEPRECATED
				    "%s (pid %d) "
				    "Use of int in max_burst socket option.\n"
				    "Use struct sctp_assoc_value instead\n",
				    current->comm, task_pid_nr(current));
		params.assoc_id = SCTP_FUTURE_ASSOC;
	} else if (len >= sizeof(struct sctp_assoc_value)) {
		len = sizeof(struct sctp_assoc_value);
		if (copy_from_user(&params, optval, len))
			return -EFAULT;
	} else
		return -EINVAL;

	asoc = sctp_id2assoc(sk, params.assoc_id);
	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	params.assoc_value = asoc ? asoc->max_burst : sctp_sk(sk)->max_burst;

	if (len == sizeof(int)) {
		if (copy_to_user(optval, &params.assoc_value, len))
			return -EFAULT;
	} else {
		if (copy_to_user(optval, &params, len))
			return -EFAULT;
	}

	return 0;

}


static int __sctp_connect(struct sock *sk, struct sockaddr *kaddrs,
			  int addrs_size, int flags, sctp_assoc_t *assoc_id)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_endpoint *ep = sp->ep;
	struct sctp_transport *transport;
	struct sctp_association *asoc;
	void *addr_buf = kaddrs;
	union sctp_addr *daddr;
	struct sctp_af *af;
	int walk_size, err;
	long timeo;

	if (sctp_sstate(sk, ESTABLISHED) || sctp_sstate(sk, CLOSING) ||
	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)))
		return -EISCONN;

	daddr = addr_buf;
	af = sctp_get_af_specific(daddr->sa.sa_family);
	if (!af || af->sockaddr_len > addrs_size)
		return -EINVAL;

	err = sctp_verify_addr(sk, daddr, af->sockaddr_len);
	if (err)
		return err;

	asoc = sctp_endpoint_lookup_assoc(ep, daddr, &transport);
	if (asoc)
		return asoc->state >= SCTP_STATE_ESTABLISHED ? -EISCONN
							     : -EALREADY;

	err = sctp_connect_new_asoc(ep, daddr, NULL, &transport);
	if (err)
		return err;
	asoc = transport->asoc;

	addr_buf += af->sockaddr_len;
	walk_size = af->sockaddr_len;
	while (walk_size < addrs_size) {
		err = -EINVAL;
		if (walk_size + sizeof(sa_family_t) > addrs_size)
			goto out_free;

		daddr = addr_buf;
		af = sctp_get_af_specific(daddr->sa.sa_family);
		if (!af || af->sockaddr_len + walk_size > addrs_size)
			goto out_free;

		if (asoc->peer.port != ntohs(daddr->v4.sin_port))
			goto out_free;

		err = sctp_connect_add_peer(asoc, daddr, af->sockaddr_len);
		if (err)
			goto out_free;

		addr_buf  += af->sockaddr_len;
		walk_size += af->sockaddr_len;
	}

	/* In case the user of sctp_connectx() wants an association
	 * id back, assign one now.
	 */
	if (assoc_id) {
		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
		if (err < 0)
			goto out_free;
	}

	err = sctp_primitive_ASSOCIATE(sock_net(sk), asoc, NULL);
	if (err < 0)
		goto out_free;

	/* Initialize sk's dport and daddr for getpeername() */
	inet_sk(sk)->inet_dport = htons(asoc->peer.port);
	sp->pf->to_sk_daddr(daddr, sk);
	sk->sk_err = 0;

	if (assoc_id)
		*assoc_id = asoc->assoc_id;

	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
	return sctp_wait_for_connect(asoc, &timeo);

out_free:
	pr_debug("%s: took out_free path with asoc:%p kaddrs:%p err:%d\n",
		 __func__, asoc, kaddrs, err);
	sctp_association_free(asoc);
	return err;
}


static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
					      struct sockaddr_storage *addr,
					      sctp_assoc_t id)
{
	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
	struct sctp_af *af = sctp_get_af_specific(addr->ss_family);
	union sctp_addr *laddr = (union sctp_addr *)addr;
	struct sctp_transport *transport;

	if (!af || sctp_verify_addr(sk, laddr, af->sockaddr_len))
		return NULL;

	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
					       laddr,
					       &transport);

	if (!addr_asoc)
		return NULL;

	id_asoc = sctp_id2assoc(sk, id);
	if (id_asoc && (id_asoc != addr_asoc))
		return NULL;

	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
						(union sctp_addr *)addr);

	return transport;
}


static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_endpoint *ep = sp->ep;
	int cnt;
	struct sctp_bind_addr *bp = &ep->base.bind_addr;
	int retval = 0;
	void *addr_buf;
	union sctp_addr *sa_addr;
	struct sctp_af *af;

	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
		 __func__, sk, addrs, addrcnt);

	addr_buf = addrs;
	for (cnt = 0; cnt < addrcnt; cnt++) {
		/* If the bind address list is empty or if there is only one
		 * bind address, there is nothing more to be removed (we need
		 * at least one address here).
		 */
		if (list_empty(&bp->address_list) ||
		    (sctp_list_single_entry(&bp->address_list))) {
			retval = -EBUSY;
			goto err_bindx_rem;
		}

		sa_addr = addr_buf;
		af = sctp_get_af_specific(sa_addr->sa.sa_family);
		if (!af) {
			retval = -EINVAL;
			goto err_bindx_rem;
		}

		if (!af->addr_valid(sa_addr, sp, NULL)) {
			retval = -EADDRNOTAVAIL;
			goto err_bindx_rem;
		}

		if (sa_addr->v4.sin_port &&
		    sa_addr->v4.sin_port != htons(bp->port)) {
			retval = -EINVAL;
			goto err_bindx_rem;
		}

		if (!sa_addr->v4.sin_port)
			sa_addr->v4.sin_port = htons(bp->port);

		/* FIXME - There is probably a need to check if sk->sk_saddr and
		 * sk->sk_rcv_addr are currently set to one of the addresses to
		 * be removed. This is something which needs to be looked into
		 * when we are fixing the outstanding issues with multi-homing
		 * socket routing and failover schemes. Refer to comments in
		 * sctp_do_bind(). -daisy
		 */
		retval = sctp_del_bind_addr(bp, sa_addr);

		addr_buf += af->sockaddr_len;
err_bindx_rem:
		if (retval < 0) {
			/* Failed. Add the ones that has been removed back */
			if (cnt > 0)
				sctp_bindx_add(sk, addrs, cnt);
			return retval;
		}
	}

	return retval;
}

static int sctp_writeable(struct sock *sk);

static void sctp_wfree(struct sk_buff *skb);

static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
				size_t msg_len);

static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);

static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);

static int sctp_wait_for_accept(struct sock *sk, long timeo);

static void sctp_wait_for_close(struct sock *sk, long timeo);

static void sctp_destruct_sock(struct sock *sk);

static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
					union sctp_addr *addr, int len);

static int sctp_bindx_add(struct sock *, struct sockaddr *, int);

static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf(struct sctp_association *asoc,
			    struct sctp_chunk *chunk);

static int sctp_do_bind(struct sock *, union sctp_addr *, int);

static int sctp_autobind(struct sock *sk);

static void sctp_sock_migrate(struct sock *, struct sock *,
			      struct sctp_association *, sctp_socket_type_t);

static int sctp_memory_pressure;

static atomic_long_t sctp_memory_allocated;

struct percpu_counter sctp_sockets_allocated;

static long sctp_get_port_local(struct sock *, union sctp_addr *);

struct compat_sctp_getaddrs_old {
	sctp_assoc_t	assoc_id;
	s32		addr_num;
	compat_uptr_t	addrs;		/* struct sockaddr * */
}

static int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);

static struct sctp_bind_bucket *sctp_bucket_create(
	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);

struct proto sctp_prot = {
	.name        =	"SCTP",
	.owner       =	THIS_MODULE,
	.close       =	sctp_close,
	.connect     =	sctp_connect,
	.disconnect  =	sctp_disconnect,
	.accept      =	sctp_accept,
	.ioctl       =	sctp_ioctl,
	.init        =	sctp_init_sock,
	.destroy     =	sctp_destroy_sock,
	.shutdown    =	sctp_shutdown,
	.setsockopt  =	sctp_setsockopt,
	.getsockopt  =	sctp_getsockopt,
	.sendmsg     =	sctp_sendmsg,
	.recvmsg     =	sctp_recvmsg,
	.bind        =	sctp_bind,
	.backlog_rcv =	sctp_backlog_rcv,
	.hash        =	sctp_hash,
	.unhash      =	sctp_unhash,
	.get_port    =	sctp_get_port,
	.obj_size    =  sizeof(struct sctp_sock),
	.sysctl_mem  =  sysctl_sctp_mem,
	.sysctl_rmem =  sysctl_sctp_rmem,
	.sysctl_wmem =  sysctl_sctp_wmem,
	.memory_pressure = &sctp_memory_pressure,
	.enter_memory_pressure = sctp_enter_memory_pressure,
	.memory_allocated = &sctp_memory_allocated,
	.sockets_allocated = &sctp_sockets_allocated,
};


static int sctp_send_asconf_del_ip(struct sock		*sk,
				   struct sockaddr	*addrs,
				   int			addrcnt)
{
	struct sctp_sock	*sp;
	struct sctp_endpoint	*ep;
	struct sctp_association	*asoc;
	struct sctp_transport	*transport;
	struct sctp_bind_addr	*bp;
	struct sctp_chunk	*chunk;
	union sctp_addr		*laddr;
	void			*addr_buf;
	struct sctp_af		*af;
	struct sctp_sockaddr_entry *saddr;
	int 			i;
	int 			retval = 0;
	int			stored = 0;

	chunk = NULL;
	sp = sctp_sk(sk);
	ep = sp->ep;

	if (!ep->asconf_enable)
		return retval;

	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
		 __func__, sk, addrs, addrcnt);

	list_for_each_entry(asoc, &ep->asocs, asocs) {

		if (!asoc->peer.asconf_capable)
			continue;

		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
			continue;

		if (!sctp_state(asoc, ESTABLISHED))
			continue;

		/* Check if any address in the packed array of addresses is
		 * not present in the bind address list of the association.
		 * If so, do not send the asconf chunk to its peer, but
		 * continue with other associations.
		 */
		addr_buf = addrs;
		for (i = 0; i < addrcnt; i++) {
			laddr = addr_buf;
			af = sctp_get_af_specific(laddr->v4.sin_family);
			if (!af) {
				retval = -EINVAL;
				goto out;
			}

			if (!sctp_assoc_lookup_laddr(asoc, laddr))
				break;

			addr_buf += af->sockaddr_len;
		}
		if (i < addrcnt)
			continue;

		/* Find one address in the association's bind address list
		 * that is not in the packed array of addresses. This is to
		 * make sure that we do not delete all the addresses in the
		 * association.
		 */
		bp = &asoc->base.bind_addr;
		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
					       addrcnt, sp);
		if ((laddr == NULL) && (addrcnt == 1)) {
			if (asoc->asconf_addr_del_pending)
				continue;
			asoc->asconf_addr_del_pending =
			    kzalloc(sizeof(union sctp_addr), GFP_ATOMIC);
			if (asoc->asconf_addr_del_pending == NULL) {
				retval = -ENOMEM;
				goto out;
			}
			asoc->asconf_addr_del_pending->sa.sa_family =
				    addrs->sa_family;
			asoc->asconf_addr_del_pending->v4.sin_port =
				    htons(bp->port);
			if (addrs->sa_family == AF_INET) {
				struct sockaddr_in *sin;

				sin = (struct sockaddr_in *)addrs;
				asoc->asconf_addr_del_pending->v4.sin_addr.s_addr = sin->sin_addr.s_addr;
			} else if (addrs->sa_family == AF_INET6) {
				struct sockaddr_in6 *sin6;

				sin6 = (struct sockaddr_in6 *)addrs;
				asoc->asconf_addr_del_pending->v6.sin6_addr = sin6->sin6_addr;
			}

			pr_debug("%s: keep the last address asoc:%p %pISc at %p\n",
				 __func__, asoc, &asoc->asconf_addr_del_pending->sa,
				 asoc->asconf_addr_del_pending);

			asoc->src_out_of_asoc_ok = 1;
			stored = 1;
			goto skip_mkasconf;
		}

		if (laddr == NULL)
			return -EINVAL;

		/* We do not need RCU protection throughout this loop
		 * because this is done under a socket lock from the
		 * setsockopt call.
		 */
		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
						   SCTP_PARAM_DEL_IP);
		if (!chunk) {
			retval = -ENOMEM;
			goto out;
		}

skip_mkasconf:
		/* Reset use_as_src flag for the addresses in the bind address
		 * list that are to be deleted.
		 */
		addr_buf = addrs;
		for (i = 0; i < addrcnt; i++) {
			laddr = addr_buf;
			af = sctp_get_af_specific(laddr->v4.sin_family);
			list_for_each_entry(saddr, &bp->address_list, list) {
				if (sctp_cmp_addr_exact(&saddr->a, laddr))
					saddr->state = SCTP_ADDR_DEL;
			}
			addr_buf += af->sockaddr_len;
		}

		/* Update the route and saddr entries for all the transports
		 * as some of the addresses in the bind address list are
		 * about to be deleted and cannot be used as source addresses.
		 */
		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
					transports) {
			sctp_transport_route(transport, NULL,
					     sctp_sk(asoc->base.sk));
		}

		if (stored)
			/* We don't need to transmit ASCONF */
			continue;
		retval = sctp_send_asconf(asoc, chunk);
	}
out:
	return retval;
}


static int sctp_setsockopt_reset_assoc(struct sock *sk, sctp_assoc_t *associd,
				       unsigned int optlen)
{
	struct sctp_association *asoc;

	if (optlen != sizeof(*associd))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, *associd);
	if (!asoc)
		return -EINVAL;

	return sctp_send_reset_assoc(asoc);
}


static void sctp_close(struct sock *sk, long timeout)
{
	struct net *net = sock_net(sk);
	struct sctp_endpoint *ep;
	struct sctp_association *asoc;
	struct list_head *pos, *temp;
	unsigned int data_was_unread;

	pr_debug("%s: sk:%p, timeout:%ld\n", __func__, sk, timeout);

	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
	sk->sk_shutdown = SHUTDOWN_MASK;
	inet_sk_set_state(sk, SCTP_SS_CLOSING);

	ep = sctp_sk(sk)->ep;

	/* Clean up any skbs sitting on the receive queue.  */
	data_was_unread = sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
	data_was_unread += sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);

	/* Walk all associations on an endpoint.  */
	list_for_each_safe(pos, temp, &ep->asocs) {
		asoc = list_entry(pos, struct sctp_association, asocs);

		if (sctp_style(sk, TCP)) {
			/* A closed association can still be in the list if
			 * it belongs to a TCP-style listening socket that is
			 * not yet accepted. If so, free it. If not, send an
			 * ABORT or SHUTDOWN based on the linger options.
			 */
			if (sctp_state(asoc, CLOSED)) {
				sctp_association_free(asoc);
				continue;
			}
		}

		if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) ||
		    !skb_queue_empty(&asoc->ulpq.reasm) ||
		    !skb_queue_empty(&asoc->ulpq.reasm_uo) ||
		    (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) {
			struct sctp_chunk *chunk;

			chunk = sctp_make_abort_user(asoc, NULL, 0);
			sctp_primitive_ABORT(net, asoc, chunk);
		} else
			sctp_primitive_SHUTDOWN(net, asoc, NULL);
	}

	/* On a TCP-style socket, block for at most linger_time if set. */
	if (sctp_style(sk, TCP) && timeout)
		sctp_wait_for_close(sk, timeout);

	/* This will run the backlog queue.  */
	release_sock(sk);

	/* Supposedly, no process has access to the socket, but
	 * the net layers still may.
	 */
	local_bh_disable();
	bh_lock_sock(sk);

	/* Hold the sock, since sk_common_release() will put sock_put()
	 * and we have just a little more cleanup.
	 */
	sock_hold(sk);
	sk_common_release(sk);

	bh_unlock_sock(sk);
	local_bh_enable();

	sock_put(sk);

	SCTP_DBG_OBJCNT_DEC(sock);
}


static int sctp_getsockopt_pf_expose(struct sock *sk, int len,
				     char __user *optval,
				     int __user *optlen)
{
	struct sctp_assoc_value params;
	struct sctp_association *asoc;
	int retval = -EFAULT;

	if (len < sizeof(params)) {
		retval = -EINVAL;
		goto out;
	}

	len = sizeof(params);
	if (copy_from_user(&params, optval, len))
		goto out;

	asoc = sctp_id2assoc(sk, params.assoc_id);
	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		retval = -EINVAL;
		goto out;
	}

	params.assoc_value = asoc ? asoc->pf_expose
				  : sctp_sk(sk)->pf_expose;

	if (put_user(len, optlen))
		goto out;

	if (copy_to_user(optval, &params, len))
		goto out;

	retval = 0;

out:
	return retval;
}


static int sctp_assoc_ulpevent_type_set(struct sctp_event *param,
					struct sctp_association *asoc)
{
	struct sctp_ulpevent *event;

	sctp_ulpevent_type_set(&asoc->subscribe, param->se_type, param->se_on);

	if (param->se_type == SCTP_SENDER_DRY_EVENT && param->se_on) {
		if (sctp_outq_is_empty(&asoc->outqueue)) {
			event = sctp_ulpevent_make_sender_dry_event(asoc,
					GFP_USER | __GFP_NOWARN);
			if (!event)
				return -ENOMEM;

			asoc->stream.si->enqueue_event(&asoc->ulpq, event);
		}
	}

	return 0;
}


static int sctp_getsockopt_encap_port(struct sock *sk, int len,
				      char __user *optval, int __user *optlen)
{
	struct sctp_association *asoc;
	struct sctp_udpencaps encap;
	struct sctp_transport *t;
	__be16 encap_port;

	if (len < sizeof(encap))
		return -EINVAL;

	len = sizeof(encap);
	if (copy_from_user(&encap, optval, len))
		return -EFAULT;

	/* If an address other than INADDR_ANY is specified, and
	 * no transport is found, then the request is invalid.
	 */
	if (!sctp_is_any(sk, (union sctp_addr *)&encap.sue_address)) {
		t = sctp_addr_id2transport(sk, &encap.sue_address,
					   encap.sue_assoc_id);
		if (!t) {
			pr_debug("%s: failed no transport\n", __func__);
			return -EINVAL;
		}

		encap_port = t->encap_port;
		goto out;
	}

	/* Get association, if assoc_id != SCTP_FUTURE_ASSOC and the
	 * socket is a one to many style socket, and an association
	 * was not found, then the id was invalid.
	 */
	asoc = sctp_id2assoc(sk, encap.sue_assoc_id);
	if (!asoc && encap.sue_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		pr_debug("%s: failed no association\n", __func__);
		return -EINVAL;
	}

	if (asoc) {
		encap_port = asoc->encap_port;
		goto out;
	}

	encap_port = sctp_sk(sk)->encap_port;

out:
	encap.sue_port = (__force uint16_t)encap_port;
	if (copy_to_user(optval, &encap, len))
		return -EFAULT;

	if (put_user(len, optlen))
		return -EFAULT;

	return 0;
}


static int sctp_setsockopt(struct sock *sk, int level, int optname,
			   sockptr_t optval, unsigned int optlen)
{
	void *kopt = NULL;
	int retval = 0;

	pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);

	/* I can hardly begin to describe how wrong this is.  This is
	 * so broken as to be worse than useless.  The API draft
	 * REALLY is NOT helpful here...  I am not convinced that the
	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
	 * are at all well-founded.
	 */
	if (level != SOL_SCTP) {
		struct sctp_af *af = sctp_sk(sk)->pf->af;

		return af->setsockopt(sk, level, optname, optval, optlen);
	}

	if (optlen > 0) {
		kopt = memdup_sockptr(optval, optlen);
		if (IS_ERR(kopt))
			return PTR_ERR(kopt);
	}

	lock_sock(sk);

	switch (optname) {
	case SCTP_SOCKOPT_BINDX_ADD:
		/* 'optlen' is the size of the addresses buffer. */
		retval = sctp_setsockopt_bindx(sk, kopt, optlen,
					       SCTP_BINDX_ADD_ADDR);
		break;

	case SCTP_SOCKOPT_BINDX_REM:
		/* 'optlen' is the size of the addresses buffer. */
		retval = sctp_setsockopt_bindx(sk, kopt, optlen,
					       SCTP_BINDX_REM_ADDR);
		break;

	case SCTP_SOCKOPT_CONNECTX_OLD:
		/* 'optlen' is the size of the addresses buffer. */
		retval = sctp_setsockopt_connectx_old(sk, kopt, optlen);
		break;

	case SCTP_SOCKOPT_CONNECTX:
		/* 'optlen' is the size of the addresses buffer. */
		retval = sctp_setsockopt_connectx(sk, kopt, optlen);
		break;

	case SCTP_DISABLE_FRAGMENTS:
		retval = sctp_setsockopt_disable_fragments(sk, kopt, optlen);
		break;

	case SCTP_EVENTS:
		retval = sctp_setsockopt_events(sk, kopt, optlen);
		break;

	case SCTP_AUTOCLOSE:
		retval = sctp_setsockopt_autoclose(sk, kopt, optlen);
		break;

	case SCTP_PEER_ADDR_PARAMS:
		retval = sctp_setsockopt_peer_addr_params(sk, kopt, optlen);
		break;

	case SCTP_DELAYED_SACK:
		retval = sctp_setsockopt_delayed_ack(sk, kopt, optlen);
		break;
	case SCTP_PARTIAL_DELIVERY_POINT:
		retval = sctp_setsockopt_partial_delivery_point(sk, kopt, optlen);
		break;

	case SCTP_INITMSG:
		retval = sctp_setsockopt_initmsg(sk, kopt, optlen);
		break;
	case SCTP_DEFAULT_SEND_PARAM:
		retval = sctp_setsockopt_default_send_param(sk, kopt, optlen);
		break;
	case SCTP_DEFAULT_SNDINFO:
		retval = sctp_setsockopt_default_sndinfo(sk, kopt, optlen);
		break;
	case SCTP_PRIMARY_ADDR:
		retval = sctp_setsockopt_primary_addr(sk, kopt, optlen);
		break;
	case SCTP_SET_PEER_PRIMARY_ADDR:
		retval = sctp_setsockopt_peer_primary_addr(sk, kopt, optlen);
		break;
	case SCTP_NODELAY:
		retval = sctp_setsockopt_nodelay(sk, kopt, optlen);
		break;
	case SCTP_RTOINFO:
		retval = sctp_setsockopt_rtoinfo(sk, kopt, optlen);
		break;
	case SCTP_ASSOCINFO:
		retval = sctp_setsockopt_associnfo(sk, kopt, optlen);
		break;
	case SCTP_I_WANT_MAPPED_V4_ADDR:
		retval = sctp_setsockopt_mappedv4(sk, kopt, optlen);
		break;
	case SCTP_MAXSEG:
		retval = sctp_setsockopt_maxseg(sk, kopt, optlen);
		break;
	case SCTP_ADAPTATION_LAYER:
		retval = sctp_setsockopt_adaptation_layer(sk, kopt, optlen);
		break;
	case SCTP_CONTEXT:
		retval = sctp_setsockopt_context(sk, kopt, optlen);
		break;
	case SCTP_FRAGMENT_INTERLEAVE:
		retval = sctp_setsockopt_fragment_interleave(sk, kopt, optlen);
		break;
	case SCTP_MAX_BURST:
		retval = sctp_setsockopt_maxburst(sk, kopt, optlen);
		break;
	case SCTP_AUTH_CHUNK:
		retval = sctp_setsockopt_auth_chunk(sk, kopt, optlen);
		break;
	case SCTP_HMAC_IDENT:
		retval = sctp_setsockopt_hmac_ident(sk, kopt, optlen);
		break;
	case SCTP_AUTH_KEY:
		retval = sctp_setsockopt_auth_key(sk, kopt, optlen);
		break;
	case SCTP_AUTH_ACTIVE_KEY:
		retval = sctp_setsockopt_active_key(sk, kopt, optlen);
		break;
	case SCTP_AUTH_DELETE_KEY:
		retval = sctp_setsockopt_del_key(sk, kopt, optlen);
		break;
	case SCTP_AUTH_DEACTIVATE_KEY:
		retval = sctp_setsockopt_deactivate_key(sk, kopt, optlen);
		break;
	case SCTP_AUTO_ASCONF:
		retval = sctp_setsockopt_auto_asconf(sk, kopt, optlen);
		break;
	case SCTP_PEER_ADDR_THLDS:
		retval = sctp_setsockopt_paddr_thresholds(sk, kopt, optlen,
							  false);
		break;
	case SCTP_PEER_ADDR_THLDS_V2:
		retval = sctp_setsockopt_paddr_thresholds(sk, kopt, optlen,
							  true);
		break;
	case SCTP_RECVRCVINFO:
		retval = sctp_setsockopt_recvrcvinfo(sk, kopt, optlen);
		break;
	case SCTP_RECVNXTINFO:
		retval = sctp_setsockopt_recvnxtinfo(sk, kopt, optlen);
		break;
	case SCTP_PR_SUPPORTED:
		retval = sctp_setsockopt_pr_supported(sk, kopt, optlen);
		break;
	case SCTP_DEFAULT_PRINFO:
		retval = sctp_setsockopt_default_prinfo(sk, kopt, optlen);
		break;
	case SCTP_RECONFIG_SUPPORTED:
		retval = sctp_setsockopt_reconfig_supported(sk, kopt, optlen);
		break;
	case SCTP_ENABLE_STREAM_RESET:
		retval = sctp_setsockopt_enable_strreset(sk, kopt, optlen);
		break;
	case SCTP_RESET_STREAMS:
		retval = sctp_setsockopt_reset_streams(sk, kopt, optlen);
		break;
	case SCTP_RESET_ASSOC:
		retval = sctp_setsockopt_reset_assoc(sk, kopt, optlen);
		break;
	case SCTP_ADD_STREAMS:
		retval = sctp_setsockopt_add_streams(sk, kopt, optlen);
		break;
	case SCTP_STREAM_SCHEDULER:
		retval = sctp_setsockopt_scheduler(sk, kopt, optlen);
		break;
	case SCTP_STREAM_SCHEDULER_VALUE:
		retval = sctp_setsockopt_scheduler_value(sk, kopt, optlen);
		break;
	case SCTP_INTERLEAVING_SUPPORTED:
		retval = sctp_setsockopt_interleaving_supported(sk, kopt,
								optlen);
		break;
	case SCTP_REUSE_PORT:
		retval = sctp_setsockopt_reuse_port(sk, kopt, optlen);
		break;
	case SCTP_EVENT:
		retval = sctp_setsockopt_event(sk, kopt, optlen);
		break;
	case SCTP_ASCONF_SUPPORTED:
		retval = sctp_setsockopt_asconf_supported(sk, kopt, optlen);
		break;
	case SCTP_AUTH_SUPPORTED:
		retval = sctp_setsockopt_auth_supported(sk, kopt, optlen);
		break;
	case SCTP_ECN_SUPPORTED:
		retval = sctp_setsockopt_ecn_supported(sk, kopt, optlen);
		break;
	case SCTP_EXPOSE_POTENTIALLY_FAILED_STATE:
		retval = sctp_setsockopt_pf_expose(sk, kopt, optlen);
		break;
	case SCTP_REMOTE_UDP_ENCAPS_PORT:
		retval = sctp_setsockopt_encap_port(sk, kopt, optlen);
		break;
	default:
		retval = -ENOPROTOOPT;
		break;
	}

	release_sock(sk);
	kfree(kopt);
	return retval;
}


static int sctp_setsockopt_ecn_supported(struct sock *sk,
					 struct sctp_assoc_value *params,
					 unsigned int optlen)
{
	struct sctp_association *asoc;
	int retval = -EINVAL;

	if (optlen != sizeof(*params))
		goto out;

	asoc = sctp_id2assoc(sk, params->assoc_id);
	if (!asoc && params->assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		goto out;

	sctp_sk(sk)->ep->ecn_enable = !!params->assoc_value;
	retval = 0;

out:
	return retval;
}


static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
					    char __user *optval,
					    int __user *optlen)
{
	struct sctp_sack_info    params;
	struct sctp_association *asoc = NULL;
	struct sctp_sock        *sp = sctp_sk(sk);

	if (len >= sizeof(struct sctp_sack_info)) {
		len = sizeof(struct sctp_sack_info);

		if (copy_from_user(&params, optval, len))
			return -EFAULT;
	} else if (len == sizeof(struct sctp_assoc_value)) {
		pr_warn_ratelimited(DEPRECATED
				    "%s (pid %d) "
				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
				    "Use struct sctp_sack_info instead\n",
				    current->comm, task_pid_nr(current));
		if (copy_from_user(&params, optval, len))
			return -EFAULT;
	} else
		return -EINVAL;

	/* Get association, if sack_assoc_id != SCTP_FUTURE_ASSOC and the
	 * socket is a one to many style socket, and an association
	 * was not found, then the id was invalid.
	 */
	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
	if (!asoc && params.sack_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		/* Fetch association values. */
		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
			params.sack_delay = jiffies_to_msecs(asoc->sackdelay);
			params.sack_freq = asoc->sackfreq;

		} else {
			params.sack_delay = 0;
			params.sack_freq = 1;
		}
	} else {
		/* Fetch socket values. */
		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
			params.sack_delay  = sp->sackdelay;
			params.sack_freq = sp->sackfreq;
		} else {
			params.sack_delay  = 0;
			params.sack_freq = 1;
		}
	}

	if (copy_to_user(optval, &params, len))
		return -EFAULT;

	if (put_user(len, optlen))
		return -EFAULT;

	return 0;
}


__poll_t sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
{
	struct sock *sk = sock->sk;
	struct sctp_sock *sp = sctp_sk(sk);
	__poll_t mask;

	poll_wait(file, sk_sleep(sk), wait);

	sock_rps_record_flow(sk);

	/* A TCP-style listening socket becomes readable when the accept queue
	 * is not empty.
	 */
	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
		return (!list_empty(&sp->ep->asocs)) ?
			(EPOLLIN | EPOLLRDNORM) : 0;

	mask = 0;

	/* Is there any exceptional events?  */
	if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
		mask |= EPOLLERR |
			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
	if (sk->sk_shutdown & RCV_SHUTDOWN)
		mask |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
	if (sk->sk_shutdown == SHUTDOWN_MASK)
		mask |= EPOLLHUP;

	/* Is it readable?  Reconsider this code with TCP-style support.  */
	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
		mask |= EPOLLIN | EPOLLRDNORM;

	/* The association is either gone or not ready.  */
	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
		return mask;

	/* Is it writable?  */
	if (sctp_writeable(sk)) {
		mask |= EPOLLOUT | EPOLLWRNORM;
	} else {
		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
		/*
		 * Since the socket is not locked, the buffer
		 * might be made available after the writeable check and
		 * before the bit is set.  This could cause a lost I/O
		 * signal.  tcp_poll() has a race breaker for this race
		 * condition.  Based on their implementation, we put
		 * in the following code to cover it as well.
		 */
		if (sctp_writeable(sk))
			mask |= EPOLLOUT | EPOLLWRNORM;
	}
	return mask;
}


static int sctp_listen_start(struct sock *sk, int backlog)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_endpoint *ep = sp->ep;
	struct crypto_shash *tfm = NULL;
	char alg[32];

	/* Allocate HMAC for generating cookie. */
	if (!sp->hmac && sp->sctp_hmac_alg) {
		sprintf(alg, "hmac(%s)", sp->sctp_hmac_alg);
		tfm = crypto_alloc_shash(alg, 0, 0);
		if (IS_ERR(tfm)) {
			net_info_ratelimited("failed to load transform for %s: %ld\n",
					     sp->sctp_hmac_alg, PTR_ERR(tfm));
			return -ENOSYS;
		}
		sctp_sk(sk)->hmac = tfm;
	}

	/*
	 * If a bind() or sctp_bindx() is not called prior to a listen()
	 * call that allows new associations to be accepted, the system
	 * picks an ephemeral port and will choose an address set equivalent
	 * to binding with a wildcard address.
	 *
	 * This is not currently spelled out in the SCTP sockets
	 * extensions draft, but follows the practice as seen in TCP
	 * sockets.
	 *
	 */
	inet_sk_set_state(sk, SCTP_SS_LISTENING);
	if (!ep->base.bind_addr.port) {
		if (sctp_autobind(sk))
			return -EAGAIN;
	} else {
		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
			inet_sk_set_state(sk, SCTP_SS_CLOSED);
			return -EADDRINUSE;
		}
	}

	WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
	return sctp_hash_endpoint(ep);
}


static int sctp_setsockopt_mappedv4(struct sock *sk, int *val,
				    unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);

	if (optlen < sizeof(int))
		return -EINVAL;
	if (*val)
		sp->v4mapped = 1;
	else
		sp->v4mapped = 0;

	return 0;
}


static int sctp_disconnect(struct sock *sk, int flags)
{
	return -EOPNOTSUPP; /* STUB */
}


void sctp_transport_walk_stop(struct rhashtable_iter *iter) __releases(RCU)
{
	rhashtable_walk_stop(iter);
	rhashtable_walk_exit(iter);
}


static void sctp_shutdown(struct sock *sk, int how)
{
	struct net *net = sock_net(sk);
	struct sctp_endpoint *ep;

	if (!sctp_style(sk, TCP))
		return;

	ep = sctp_sk(sk)->ep;
	if (how & SEND_SHUTDOWN && !list_empty(&ep->asocs)) {
		struct sctp_association *asoc;

		inet_sk_set_state(sk, SCTP_SS_CLOSING);
		asoc = list_entry(ep->asocs.next,
				  struct sctp_association, asocs);
		sctp_primitive_SHUTDOWN(net, asoc, NULL);
	}
}


static int sctp_setsockopt_auto_asconf(struct sock *sk, int *val,
					unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);

	if (optlen < sizeof(int))
		return -EINVAL;
	if (!sctp_is_ep_boundall(sk) && *val)
		return -EINVAL;
	if ((*val && sp->do_auto_asconf) || (!*val && !sp->do_auto_asconf))
		return 0;

	spin_lock_bh(&sock_net(sk)->sctp.addr_wq_lock);
	if (*val == 0 && sp->do_auto_asconf) {
		list_del(&sp->auto_asconf_list);
		sp->do_auto_asconf = 0;
	} else if (*val && !sp->do_auto_asconf) {
		list_add_tail(&sp->auto_asconf_list,
		    &sock_net(sk)->sctp.auto_asconf_splist);
		sp->do_auto_asconf = 1;
	}
	spin_unlock_bh(&sock_net(sk)->sctp.addr_wq_lock);
	return 0;
}


static int sctp_bind_add(struct sock *sk, struct sockaddr *addrs,
		int addrlen)
{
	int err;

	lock_sock(sk);
	err = sctp_setsockopt_bindx(sk, addrs, addrlen, SCTP_BINDX_ADD_ADDR);
	release_sock(sk);
	return err;
}


static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
				struct msghdr *msg, size_t msg_len,
				struct sctp_transport *transport,
				struct sctp_sndrcvinfo *sinfo)
{
	struct sock *sk = asoc->base.sk;
	struct sctp_sock *sp = sctp_sk(sk);
	struct net *net = sock_net(sk);
	struct sctp_datamsg *datamsg;
	bool wait_connect = false;
	struct sctp_chunk *chunk;
	long timeo;
	int err;

	if (sinfo->sinfo_stream >= asoc->stream.outcnt) {
		err = -EINVAL;
		goto err;
	}

	if (unlikely(!SCTP_SO(&asoc->stream, sinfo->sinfo_stream)->ext)) {
		err = sctp_stream_init_ext(&asoc->stream, sinfo->sinfo_stream);
		if (err)
			goto err;
	}

	if (sp->disable_fragments && msg_len > asoc->frag_point) {
		err = -EMSGSIZE;
		goto err;
	}

	if (asoc->pmtu_pending) {
		if (sp->param_flags & SPP_PMTUD_ENABLE)
			sctp_assoc_sync_pmtu(asoc);
		asoc->pmtu_pending = 0;
	}

	if (sctp_wspace(asoc) < (int)msg_len)
		sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));

	if (sk_under_memory_pressure(sk))
		sk_mem_reclaim(sk);

	if (sctp_wspace(asoc) <= 0 || !sk_wmem_schedule(sk, msg_len)) {
		timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
		if (err)
			goto err;
	}

	if (sctp_state(asoc, CLOSED)) {
		err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
		if (err)
			goto err;

		if (asoc->ep->intl_enable) {
			timeo = sock_sndtimeo(sk, 0);
			err = sctp_wait_for_connect(asoc, &timeo);
			if (err) {
				err = -ESRCH;
				goto err;
			}
		} else {
			wait_connect = true;
		}

		pr_debug("%s: we associated primitively\n", __func__);
	}

	datamsg = sctp_datamsg_from_user(asoc, sinfo, &msg->msg_iter);
	if (IS_ERR(datamsg)) {
		err = PTR_ERR(datamsg);
		goto err;
	}

	asoc->force_delay = !!(msg->msg_flags & MSG_MORE);

	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
		sctp_chunk_hold(chunk);
		sctp_set_owner_w(chunk);
		chunk->transport = transport;
	}

	err = sctp_primitive_SEND(net, asoc, datamsg);
	if (err) {
		sctp_datamsg_free(datamsg);
		goto err;
	}

	pr_debug("%s: we sent primitively\n", __func__);

	sctp_datamsg_put(datamsg);

	if (unlikely(wait_connect)) {
		timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
		sctp_wait_for_connect(asoc, &timeo);
	}

	err = msg_len;

err:
	return err;
}


static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
				size_t msg_len)
{
	struct sock *sk = asoc->base.sk;
	long current_timeo = *timeo_p;
	DEFINE_WAIT(wait);
	int err = 0;

	pr_debug("%s: asoc:%p, timeo:%ld, msg_len:%zu\n", __func__, asoc,
		 *timeo_p, msg_len);

	/* Increment the association's refcnt.  */
	sctp_association_hold(asoc);

	/* Wait on the association specific sndbuf space. */
	for (;;) {
		prepare_to_wait_exclusive(&asoc->wait, &wait,
					  TASK_INTERRUPTIBLE);
		if (asoc->base.dead)
			goto do_dead;
		if (!*timeo_p)
			goto do_nonblock;
		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING)
			goto do_error;
		if (signal_pending(current))
			goto do_interrupted;
		if (sk_under_memory_pressure(sk))
			sk_mem_reclaim(sk);
		if ((int)msg_len <= sctp_wspace(asoc) &&
		    sk_wmem_schedule(sk, msg_len))
			break;

		/* Let another process have a go.  Since we are going
		 * to sleep anyway.
		 */
		release_sock(sk);
		current_timeo = schedule_timeout(current_timeo);
		lock_sock(sk);
		if (sk != asoc->base.sk)
			goto do_error;

		*timeo_p = current_timeo;
	}

out:
	finish_wait(&asoc->wait, &wait);

	/* Release the association's refcnt.  */
	sctp_association_put(asoc);

	return err;

do_dead:
	err = -ESRCH;
	goto out;

do_error:
	err = -EPIPE;
	goto out;

do_interrupted:
	err = sock_intr_errno(*timeo_p);
	goto out;

do_nonblock:
	err = -EAGAIN;
	goto out;
}


static int sctp_setsockopt_context(struct sock *sk,
				   struct sctp_assoc_value *params,
				   unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;

	if (optlen != sizeof(struct sctp_assoc_value))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, params->assoc_id);
	if (!asoc && params->assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		asoc->default_rcv_context = params->assoc_value;

		return 0;
	}

	if (sctp_style(sk, TCP))
		params->assoc_id = SCTP_FUTURE_ASSOC;

	if (params->assoc_id == SCTP_FUTURE_ASSOC ||
	    params->assoc_id == SCTP_ALL_ASSOC)
		sp->default_rcv_context = params->assoc_value;

	if (params->assoc_id == SCTP_CURRENT_ASSOC ||
	    params->assoc_id == SCTP_ALL_ASSOC)
		list_for_each_entry(asoc, &sp->ep->asocs, asocs)
			asoc->default_rcv_context = params->assoc_value;

	return 0;
}


static int sctp_getsockopt_event(struct sock *sk, int len, char __user *optval,
				 int __user *optlen)
{
	struct sctp_association *asoc;
	struct sctp_event param;
	__u16 subscribe;

	if (len < sizeof(param))
		return -EINVAL;

	len = sizeof(param);
	if (copy_from_user(&param, optval, len))
		return -EFAULT;

	if (param.se_type < SCTP_SN_TYPE_BASE ||
	    param.se_type > SCTP_SN_TYPE_MAX)
		return -EINVAL;

	asoc = sctp_id2assoc(sk, param.se_assoc_id);
	if (!asoc && param.se_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	subscribe = asoc ? asoc->subscribe : sctp_sk(sk)->subscribe;
	param.se_on = sctp_ulpevent_type_enabled(subscribe, param.se_type);

	if (put_user(len, optlen))
		return -EFAULT;

	if (copy_to_user(optval, &param, len))
		return -EFAULT;

	return 0;
}


static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
					    char __user *optval, int __user *optlen)
{
	struct sctp_paddrparams  params;
	struct sctp_transport   *trans = NULL;
	struct sctp_association *asoc = NULL;
	struct sctp_sock        *sp = sctp_sk(sk);

	if (len >= sizeof(params))
		len = sizeof(params);
	else if (len >= ALIGN(offsetof(struct sctp_paddrparams,
				       spp_ipv6_flowlabel), 4))
		len = ALIGN(offsetof(struct sctp_paddrparams,
				     spp_ipv6_flowlabel), 4);
	else
		return -EINVAL;

	if (copy_from_user(&params, optval, len))
		return -EFAULT;

	/* If an address other than INADDR_ANY is specified, and
	 * no transport is found, then the request is invalid.
	 */
	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
		trans = sctp_addr_id2transport(sk, &params.spp_address,
					       params.spp_assoc_id);
		if (!trans) {
			pr_debug("%s: failed no transport\n", __func__);
			return -EINVAL;
		}
	}

	/* Get association, if assoc_id != SCTP_FUTURE_ASSOC and the
	 * socket is a one to many style socket, and an association
	 * was not found, then the id was invalid.
	 */
	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
	if (!asoc && params.spp_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		pr_debug("%s: failed no association\n", __func__);
		return -EINVAL;
	}

	if (trans) {
		/* Fetch transport values. */
		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
		params.spp_pathmtu    = trans->pathmtu;
		params.spp_pathmaxrxt = trans->pathmaxrxt;
		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);

		/*draft-11 doesn't say what to return in spp_flags*/
		params.spp_flags      = trans->param_flags;
		if (trans->flowlabel & SCTP_FLOWLABEL_SET_MASK) {
			params.spp_ipv6_flowlabel = trans->flowlabel &
						    SCTP_FLOWLABEL_VAL_MASK;
			params.spp_flags |= SPP_IPV6_FLOWLABEL;
		}
		if (trans->dscp & SCTP_DSCP_SET_MASK) {
			params.spp_dscp	= trans->dscp & SCTP_DSCP_VAL_MASK;
			params.spp_flags |= SPP_DSCP;
		}
	} else if (asoc) {
		/* Fetch association values. */
		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
		params.spp_pathmtu    = asoc->pathmtu;
		params.spp_pathmaxrxt = asoc->pathmaxrxt;
		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);

		/*draft-11 doesn't say what to return in spp_flags*/
		params.spp_flags      = asoc->param_flags;
		if (asoc->flowlabel & SCTP_FLOWLABEL_SET_MASK) {
			params.spp_ipv6_flowlabel = asoc->flowlabel &
						    SCTP_FLOWLABEL_VAL_MASK;
			params.spp_flags |= SPP_IPV6_FLOWLABEL;
		}
		if (asoc->dscp & SCTP_DSCP_SET_MASK) {
			params.spp_dscp	= asoc->dscp & SCTP_DSCP_VAL_MASK;
			params.spp_flags |= SPP_DSCP;
		}
	} else {
		/* Fetch socket values. */
		params.spp_hbinterval = sp->hbinterval;
		params.spp_pathmtu    = sp->pathmtu;
		params.spp_sackdelay  = sp->sackdelay;
		params.spp_pathmaxrxt = sp->pathmaxrxt;

		/*draft-11 doesn't say what to return in spp_flags*/
		params.spp_flags      = sp->param_flags;
		if (sp->flowlabel & SCTP_FLOWLABEL_SET_MASK) {
			params.spp_ipv6_flowlabel = sp->flowlabel &
						    SCTP_FLOWLABEL_VAL_MASK;
			params.spp_flags |= SPP_IPV6_FLOWLABEL;
		}
		if (sp->dscp & SCTP_DSCP_SET_MASK) {
			params.spp_dscp	= sp->dscp & SCTP_DSCP_VAL_MASK;
			params.spp_flags |= SPP_DSCP;
		}
	}

	if (copy_to_user(optval, &params, len))
		return -EFAULT;

	if (put_user(len, optlen))
		return -EFAULT;

	return 0;
}


static void sctp_sendmsg_update_sinfo(struct sctp_association *asoc,
				      struct sctp_sndrcvinfo *sinfo,
				      struct sctp_cmsgs *cmsgs)
{
	if (!cmsgs->srinfo && !cmsgs->sinfo) {
		sinfo->sinfo_stream = asoc->default_stream;
		sinfo->sinfo_ppid = asoc->default_ppid;
		sinfo->sinfo_context = asoc->default_context;
		sinfo->sinfo_assoc_id = sctp_assoc2id(asoc);

		if (!cmsgs->prinfo)
			sinfo->sinfo_flags = asoc->default_flags;
	}

	if (!cmsgs->srinfo && !cmsgs->prinfo)
		sinfo->sinfo_timetolive = asoc->default_timetolive;

	if (cmsgs->authinfo) {
		/* Reuse sinfo_tsn to indicate that authinfo was set and
		 * sinfo_ssn to save the keyid on tx path.
		 */
		sinfo->sinfo_tsn = 1;
		sinfo->sinfo_ssn = cmsgs->authinfo->auth_keynumber;
	}
}


static int sctp_getsockopt_interleaving_supported(struct sock *sk, int len,
						  char __user *optval,
						  int __user *optlen)
{
	struct sctp_assoc_value params;
	struct sctp_association *asoc;
	int retval = -EFAULT;

	if (len < sizeof(params)) {
		retval = -EINVAL;
		goto out;
	}

	len = sizeof(params);
	if (copy_from_user(&params, optval, len))
		goto out;

	asoc = sctp_id2assoc(sk, params.assoc_id);
	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		retval = -EINVAL;
		goto out;
	}

	params.assoc_value = asoc ? asoc->peer.intl_capable
				  : sctp_sk(sk)->ep->intl_enable;

	if (put_user(len, optlen))
		goto out;

	if (copy_to_user(optval, &params, len))
		goto out;

	retval = 0;

out:
	return retval;
}


static int sctp_setsockopt_deactivate_key(struct sock *sk,
					  struct sctp_authkeyid *val,
					  unsigned int optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	struct sctp_association *asoc;
	int ret = 0;

	if (optlen != sizeof(struct sctp_authkeyid))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, val->scact_assoc_id);
	if (!asoc && val->scact_assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc)
		return sctp_auth_deact_key_id(ep, asoc, val->scact_keynumber);

	if (sctp_style(sk, TCP))
		val->scact_assoc_id = SCTP_FUTURE_ASSOC;

	if (val->scact_assoc_id == SCTP_FUTURE_ASSOC ||
	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
		ret = sctp_auth_deact_key_id(ep, asoc, val->scact_keynumber);
		if (ret)
			return ret;
	}

	if (val->scact_assoc_id == SCTP_CURRENT_ASSOC ||
	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
		list_for_each_entry(asoc, &ep->asocs, asocs) {
			int res = sctp_auth_deact_key_id(ep, asoc,
							 val->scact_keynumber);

			if (res && !ret)
				ret = res;
		}
	}

	return ret;
}


static int sctp_setsockopt_default_sndinfo(struct sock *sk,
					   struct sctp_sndinfo *info,
					   unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;

	if (optlen != sizeof(*info))
		return -EINVAL;
	if (info->snd_flags &
	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
	      SCTP_ABORT | SCTP_EOF))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, info->snd_assoc_id);
	if (!asoc && info->snd_assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		asoc->default_stream = info->snd_sid;
		asoc->default_flags = info->snd_flags;
		asoc->default_ppid = info->snd_ppid;
		asoc->default_context = info->snd_context;

		return 0;
	}

	if (sctp_style(sk, TCP))
		info->snd_assoc_id = SCTP_FUTURE_ASSOC;

	if (info->snd_assoc_id == SCTP_FUTURE_ASSOC ||
	    info->snd_assoc_id == SCTP_ALL_ASSOC) {
		sp->default_stream = info->snd_sid;
		sp->default_flags = info->snd_flags;
		sp->default_ppid = info->snd_ppid;
		sp->default_context = info->snd_context;
	}

	if (info->snd_assoc_id == SCTP_CURRENT_ASSOC ||
	    info->snd_assoc_id == SCTP_ALL_ASSOC) {
		list_for_each_entry(asoc, &sp->ep->asocs, asocs) {
			asoc->default_stream = info->snd_sid;
			asoc->default_flags = info->snd_flags;
			asoc->default_ppid = info->snd_ppid;
			asoc->default_context = info->snd_context;
		}
	}

	return 0;
}


static int sctp_getsockopt_reuse_port(struct sock *sk, int len,
				      char __user *optval,
				      int __user *optlen)
{
	int val;

	if (len < sizeof(int))
		return -EINVAL;

	len = sizeof(int);
	val = sctp_sk(sk)->reuse;
	if (put_user(len, optlen))
		return -EFAULT;

	if (copy_to_user(optval, &val, len))
		return -EFAULT;

	return 0;
}


static int sctp_setsockopt_events(struct sock *sk, __u8 *sn_type,
				  unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;
	int i;

	if (optlen > sizeof(struct sctp_event_subscribe))
		return -EINVAL;

	for (i = 0; i < optlen; i++)
		sctp_ulpevent_type_set(&sp->subscribe, SCTP_SN_TYPE_BASE + i,
				       sn_type[i]);

	list_for_each_entry(asoc, &sp->ep->asocs, asocs)
		asoc->subscribe = sctp_sk(sk)->subscribe;

	/* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
	 * if there is no data to be sent or retransmit, the stack will
	 * immediately send up this notification.
	 */
	if (sctp_ulpevent_type_enabled(sp->subscribe, SCTP_SENDER_DRY_EVENT)) {
		struct sctp_ulpevent *event;

		asoc = sctp_id2assoc(sk, 0);
		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
			event = sctp_ulpevent_make_sender_dry_event(asoc,
					GFP_USER | __GFP_NOWARN);
			if (!event)
				return -ENOMEM;

			asoc->stream.si->enqueue_event(&asoc->ulpq, event);
		}
	}

	return 0;
}


static int sctp_setsockopt_auth_chunk(struct sock *sk,
				      struct sctp_authchunk *val,
				      unsigned int optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;

	if (!ep->auth_enable)
		return -EACCES;

	if (optlen != sizeof(struct sctp_authchunk))
		return -EINVAL;

	switch (val->sauth_chunk) {
	case SCTP_CID_INIT:
	case SCTP_CID_INIT_ACK:
	case SCTP_CID_SHUTDOWN_COMPLETE:
	case SCTP_CID_AUTH:
		return -EINVAL;
	}

	/* add this chunk id to the endpoint */
	return sctp_auth_ep_add_chunkid(ep, val->sauth_chunk);
}


static int sctp_setsockopt_event(struct sock *sk, struct sctp_event *param,
				 unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;
	int retval = 0;

	if (optlen < sizeof(*param))
		return -EINVAL;

	if (param->se_type < SCTP_SN_TYPE_BASE ||
	    param->se_type > SCTP_SN_TYPE_MAX)
		return -EINVAL;

	asoc = sctp_id2assoc(sk, param->se_assoc_id);
	if (!asoc && param->se_assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc)
		return sctp_assoc_ulpevent_type_set(param, asoc);

	if (sctp_style(sk, TCP))
		param->se_assoc_id = SCTP_FUTURE_ASSOC;

	if (param->se_assoc_id == SCTP_FUTURE_ASSOC ||
	    param->se_assoc_id == SCTP_ALL_ASSOC)
		sctp_ulpevent_type_set(&sp->subscribe,
				       param->se_type, param->se_on);

	if (param->se_assoc_id == SCTP_CURRENT_ASSOC ||
	    param->se_assoc_id == SCTP_ALL_ASSOC) {
		list_for_each_entry(asoc, &sp->ep->asocs, asocs) {
			int ret = sctp_assoc_ulpevent_type_set(param, asoc);

			if (ret && !retval)
				retval = ret;
		}
	}

	return retval;
}


struct sctp_transport *sctp_transport_get_idx(struct net *net,
					      struct rhashtable_iter *iter,
					      int pos)
{
	struct sctp_transport *t;

	if (!pos)
		return SEQ_START_TOKEN;

	while ((t = sctp_transport_get_next(net, iter)) && !IS_ERR(t)) {
		if (!--pos)
			break;
		sctp_transport_put(t);
	}

	return t;
}

static bool sctp_writeable(struct sock *sk);

static void sctp_wfree(struct sk_buff *skb);

static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
				size_t msg_len);

static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);

static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);

static int sctp_wait_for_accept(struct sock *sk, long timeo);

static void sctp_wait_for_close(struct sock *sk, long timeo);

static void sctp_destruct_sock(struct sock *sk);

static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
					union sctp_addr *addr, int len);

static int sctp_bindx_add(struct sock *, struct sockaddr *, int);

static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);

static int sctp_send_asconf(struct sctp_association *asoc,
			    struct sctp_chunk *chunk);

static int sctp_do_bind(struct sock *, union sctp_addr *, int);

static int sctp_autobind(struct sock *sk);

static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
			     struct sctp_association *assoc,
			     enum sctp_socket_type type);

struct percpu_counter sctp_sockets_allocated;

#define traverse_and_process()	\
do {				\
	msg = chunk->msg;	\
	if (msg == prev_msg)	\
		continue;	\
	list_for_each_entry(c, &msg->chunks, frag_list) {	\
		if ((clear && asoc->base.sk == c->skb->sk) ||	\
		    (!clear && asoc->base.sk != c->skb->sk))	\
			cb(c);	\
	}			\
	prev_msg = msg;		\
} while (0)

static int sctp_get_port_local(struct sock *, union sctp_addr *);

struct compat_sctp_getaddrs_old {
	sctp_assoc_t	assoc_id;
	s32		addr_num;
	compat_uptr_t	addrs;		/* struct sockaddr * */
}

static int sctp_msghdr_parse(const struct msghdr *msg,
			     struct sctp_cmsgs *cmsgs);

static struct sctp_bind_bucket *sctp_bucket_create(
	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);


static int sctp_getsockopt_peeloff_flags(struct sock *sk, int len,
					 char __user *optval, int __user *optlen)
{
	sctp_peeloff_flags_arg_t peeloff;
	struct file *newfile = NULL;
	int retval = 0;

	if (len < sizeof(sctp_peeloff_flags_arg_t))
		return -EINVAL;
	len = sizeof(sctp_peeloff_flags_arg_t);
	if (copy_from_user(&peeloff, optval, len))
		return -EFAULT;

	retval = sctp_getsockopt_peeloff_common(sk, &peeloff.p_arg,
						&newfile, peeloff.flags);
	if (retval < 0)
		goto out;

	/* Return the fd mapped to the new socket.  */
	if (put_user(len, optlen)) {
		fput(newfile);
		put_unused_fd(retval);
		return -EFAULT;
	}

	if (copy_to_user(optval, &peeloff, len)) {
		fput(newfile);
		put_unused_fd(retval);
		return -EFAULT;
	}
	fd_install(retval, newfile);
out:
	return retval;
}


static inline void __sctp_put_port(struct sock *sk)
{
	struct sctp_bind_hashbucket *head =
		&sctp_port_hashtable[sctp_phashfn(sock_net(sk),
						  inet_sk(sk)->inet_num)];
	struct sctp_bind_bucket *pp;

	spin_lock(&head->lock);
	pp = sctp_sk(sk)->bind_hash;
	__sk_del_bind_node(sk);
	sctp_sk(sk)->bind_hash = NULL;
	inet_sk(sk)->inet_num = 0;
	sctp_bucket_destroy(pp);
	spin_unlock(&head->lock);
}


static int sctp_wait_for_accept(struct sock *sk, long timeo)
{
	struct sctp_endpoint *ep;
	int err = 0;
	DEFINE_WAIT(wait);

	ep = sctp_sk(sk)->ep;

	for (;;) {
		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
					  TASK_INTERRUPTIBLE);

		if (list_empty(&ep->asocs)) {
			release_sock(sk);
			timeo = schedule_timeout(timeo);
			lock_sock(sk);
		}

		err = -EINVAL;
		if (!sctp_sstate(sk, LISTENING))
			break;

		err = 0;
		if (!list_empty(&ep->asocs))
			break;

		err = sock_intr_errno(timeo);
		if (signal_pending(current))
			break;

		err = -EAGAIN;
		if (!timeo)
			break;
	}

	finish_wait(sk_sleep(sk), &wait);

	return err;
}


static int sctp_getsockopt_default_prinfo(struct sock *sk, int len,
					  char __user *optval,
					  int __user *optlen)
{
	struct sctp_default_prinfo info;
	struct sctp_association *asoc;
	int retval = -EFAULT;

	if (len < sizeof(info)) {
		retval = -EINVAL;
		goto out;
	}

	len = sizeof(info);
	if (copy_from_user(&info, optval, len))
		goto out;

	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
	if (!asoc && info.pr_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		retval = -EINVAL;
		goto out;
	}

	if (asoc) {
		info.pr_policy = SCTP_PR_POLICY(asoc->default_flags);
		info.pr_value = asoc->default_timetolive;
	} else {
		struct sctp_sock *sp = sctp_sk(sk);

		info.pr_policy = SCTP_PR_POLICY(sp->default_flags);
		info.pr_value = sp->default_timetolive;
	}

	if (put_user(len, optlen))
		goto out;

	if (copy_to_user(optval, &info, len))
		goto out;

	retval = 0;

out:
	return retval;
}


static int __sctp_setsockopt_connectx(struct sock *sk, struct sockaddr *kaddrs,
				      int addrs_size, sctp_assoc_t *assoc_id)
{
	int err = 0, flags = 0;

	pr_debug("%s: sk:%p addrs:%p addrs_size:%d\n",
		 __func__, sk, kaddrs, addrs_size);

	/* make sure the 1st addr's sa_family is accessible later */
	if (unlikely(addrs_size < sizeof(sa_family_t)))
		return -EINVAL;

	/* Allow security module to validate connectx addresses. */
	err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX,
					 (struct sockaddr *)kaddrs,
					  addrs_size);
	if (err)
		return err;

	/* in-kernel sockets don't generally have a file allocated to them
	 * if all they do is call sock_create_kern().
	 */
	if (sk->sk_socket->file)
		flags = sk->sk_socket->file->f_flags;

	return __sctp_connect(sk, kaddrs, addrs_size, flags, assoc_id);
}


static void sctp_v6_destroy_sock(struct sock *sk)
{
	sctp_destroy_sock(sk);
	inet6_destroy_sock(sk);
}


static int sctp_connect(struct sock *sk, struct sockaddr *addr,
			int addr_len, int flags)
{
	struct sctp_af *af;
	int err = -EINVAL;

	lock_sock(sk);
	pr_debug("%s: sk:%p, sockaddr:%p, addr_len:%d\n", __func__, sk,
		 addr, addr_len);

	/* Validate addr_len before calling common connect/connectx routine. */
	af = sctp_get_af_specific(addr->sa_family);
	if (af && addr_len >= af->sockaddr_len)
		err = __sctp_connect(sk, addr, af->sockaddr_len, flags, NULL);

	release_sock(sk);
	return err;
}


static int sctp_setsockopt_pr_supported(struct sock *sk,
					struct sctp_assoc_value *params,
					unsigned int optlen)
{
	struct sctp_association *asoc;

	if (optlen != sizeof(*params))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, params->assoc_id);
	if (!asoc && params->assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	sctp_sk(sk)->ep->prsctp_enable = !!params->assoc_value;

	return 0;
}


static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
					  char __user *optval,
					  int __user *optlen)
{
	struct sctp_paddrinfo pinfo;
	struct sctp_transport *transport;
	int retval = 0;

	if (len < sizeof(pinfo)) {
		retval = -EINVAL;
		goto out;
	}

	len = sizeof(pinfo);
	if (copy_from_user(&pinfo, optval, len)) {
		retval = -EFAULT;
		goto out;
	}

	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
					   pinfo.spinfo_assoc_id);
	if (!transport) {
		retval = -EINVAL;
		goto out;
	}

	if (transport->state == SCTP_PF &&
	    transport->asoc->pf_expose == SCTP_PF_EXPOSE_DISABLE) {
		retval = -EACCES;
		goto out;
	}

	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
	pinfo.spinfo_state = transport->state;
	pinfo.spinfo_cwnd = transport->cwnd;
	pinfo.spinfo_srtt = transport->srtt;
	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
	pinfo.spinfo_mtu = transport->pathmtu;

	if (pinfo.spinfo_state == SCTP_UNKNOWN)
		pinfo.spinfo_state = SCTP_ACTIVE;

	if (put_user(len, optlen)) {
		retval = -EFAULT;
		goto out;
	}

	if (copy_to_user(optval, &pinfo, len)) {
		retval = -EFAULT;
		goto out;
	}

out:
	return retval;
}


static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len,
					  char __user *optval,
					  int __user *optlen)
{
	struct sctp_prstatus params;
	struct sctp_association *asoc;
	int policy;
	int retval = -EINVAL;

	if (len < sizeof(params))
		goto out;

	len = sizeof(params);
	if (copy_from_user(&params, optval, len)) {
		retval = -EFAULT;
		goto out;
	}

	policy = params.sprstat_policy;
	if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) ||
	    ((policy & SCTP_PR_SCTP_ALL) && (policy & SCTP_PR_SCTP_MASK)))
		goto out;

	asoc = sctp_id2assoc(sk, params.sprstat_assoc_id);
	if (!asoc)
		goto out;

	if (policy == SCTP_PR_SCTP_ALL) {
		params.sprstat_abandoned_unsent = 0;
		params.sprstat_abandoned_sent = 0;
		for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) {
			params.sprstat_abandoned_unsent +=
				asoc->abandoned_unsent[policy];
			params.sprstat_abandoned_sent +=
				asoc->abandoned_sent[policy];
		}
	} else {
		params.sprstat_abandoned_unsent =
			asoc->abandoned_unsent[__SCTP_PR_INDEX(policy)];
		params.sprstat_abandoned_sent =
			asoc->abandoned_sent[__SCTP_PR_INDEX(policy)];
	}

	if (put_user(len, optlen)) {
		retval = -EFAULT;
		goto out;
	}

	if (copy_to_user(optval, &params, len)) {
		retval = -EFAULT;
		goto out;
	}

	retval = 0;

out:
	return retval;
}


static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
					    struct sctp_paddrthlds_v2 *val,
					    unsigned int optlen, bool v2)
{
	struct sctp_transport *trans;
	struct sctp_association *asoc;
	int len;

	len = v2 ? sizeof(*val) : sizeof(struct sctp_paddrthlds);
	if (optlen < len)
		return -EINVAL;

	if (v2 && val->spt_pathpfthld > val->spt_pathcpthld)
		return -EINVAL;

	if (!sctp_is_any(sk, (const union sctp_addr *)&val->spt_address)) {
		trans = sctp_addr_id2transport(sk, &val->spt_address,
					       val->spt_assoc_id);
		if (!trans)
			return -ENOENT;

		if (val->spt_pathmaxrxt)
			trans->pathmaxrxt = val->spt_pathmaxrxt;
		if (v2)
			trans->ps_retrans = val->spt_pathcpthld;
		trans->pf_retrans = val->spt_pathpfthld;

		return 0;
	}

	asoc = sctp_id2assoc(sk, val->spt_assoc_id);
	if (!asoc && val->spt_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
				    transports) {
			if (val->spt_pathmaxrxt)
				trans->pathmaxrxt = val->spt_pathmaxrxt;
			if (v2)
				trans->ps_retrans = val->spt_pathcpthld;
			trans->pf_retrans = val->spt_pathpfthld;
		}

		if (val->spt_pathmaxrxt)
			asoc->pathmaxrxt = val->spt_pathmaxrxt;
		if (v2)
			asoc->ps_retrans = val->spt_pathcpthld;
		asoc->pf_retrans = val->spt_pathpfthld;
	} else {
		struct sctp_sock *sp = sctp_sk(sk);

		if (val->spt_pathmaxrxt)
			sp->pathmaxrxt = val->spt_pathmaxrxt;
		if (v2)
			sp->ps_retrans = val->spt_pathcpthld;
		sp->pf_retrans = val->spt_pathpfthld;
	}

	return 0;
}


static int sctp_hash(struct sock *sk)
{
	/* STUB */
	return 0;
}


static int __sctp_setsockopt_delayed_ack(struct sock *sk,
					 struct sctp_sack_info *params)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;

	/* Validate value parameter. */
	if (params->sack_delay > 500)
		return -EINVAL;

	/* Get association, if sack_assoc_id != SCTP_FUTURE_ASSOC and the
	 * socket is a one to many style socket, and an association
	 * was not found, then the id was invalid.
	 */
	asoc = sctp_id2assoc(sk, params->sack_assoc_id);
	if (!asoc && params->sack_assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		sctp_apply_asoc_delayed_ack(params, asoc);

		return 0;
	}

	if (sctp_style(sk, TCP))
		params->sack_assoc_id = SCTP_FUTURE_ASSOC;

	if (params->sack_assoc_id == SCTP_FUTURE_ASSOC ||
	    params->sack_assoc_id == SCTP_ALL_ASSOC) {
		if (params->sack_delay) {
			sp->sackdelay = params->sack_delay;
			sp->param_flags =
				sctp_spp_sackdelay_enable(sp->param_flags);
		}
		if (params->sack_freq == 1) {
			sp->param_flags =
				sctp_spp_sackdelay_disable(sp->param_flags);
		} else if (params->sack_freq > 1) {
			sp->sackfreq = params->sack_freq;
			sp->param_flags =
				sctp_spp_sackdelay_enable(sp->param_flags);
		}
	}

	if (params->sack_assoc_id == SCTP_CURRENT_ASSOC ||
	    params->sack_assoc_id == SCTP_ALL_ASSOC)
		list_for_each_entry(asoc, &sp->ep->asocs, asocs)
			sctp_apply_asoc_delayed_ack(params, asoc);

	return 0;
}


static int sctp_getsockopt_active_key(struct sock *sk, int len,
				    char __user *optval, int __user *optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	struct sctp_authkeyid val;
	struct sctp_association *asoc;

	if (len < sizeof(struct sctp_authkeyid))
		return -EINVAL;

	len = sizeof(struct sctp_authkeyid);
	if (copy_from_user(&val, optval, len))
		return -EFAULT;

	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		if (!asoc->peer.auth_capable)
			return -EACCES;
		val.scact_keynumber = asoc->active_key_id;
	} else {
		if (!ep->auth_enable)
			return -EACCES;
		val.scact_keynumber = ep->active_key_id;
	}

	if (put_user(len, optlen))
		return -EFAULT;
	if (copy_to_user(optval, &val, len))
		return -EFAULT;

	return 0;
}


static int sctp_setsockopt_associnfo(struct sock *sk,
				     struct sctp_assocparams *assocparams,
				     unsigned int optlen)
{

	struct sctp_association *asoc;

	if (optlen != sizeof(struct sctp_assocparams))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, assocparams->sasoc_assoc_id);

	if (!asoc && assocparams->sasoc_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	/* Set the values to the specific association */
	if (asoc) {
		if (assocparams->sasoc_asocmaxrxt != 0) {
			__u32 path_sum = 0;
			int   paths = 0;
			struct sctp_transport *peer_addr;

			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
					transports) {
				path_sum += peer_addr->pathmaxrxt;
				paths++;
			}

			/* Only validate asocmaxrxt if we have more than
			 * one path/transport.  We do this because path
			 * retransmissions are only counted when we have more
			 * then one path.
			 */
			if (paths > 1 &&
			    assocparams->sasoc_asocmaxrxt > path_sum)
				return -EINVAL;

			asoc->max_retrans = assocparams->sasoc_asocmaxrxt;
		}

		if (assocparams->sasoc_cookie_life != 0)
			asoc->cookie_life =
				ms_to_ktime(assocparams->sasoc_cookie_life);
	} else {
		/* Set the values to the endpoint */
		struct sctp_sock *sp = sctp_sk(sk);

		if (assocparams->sasoc_asocmaxrxt != 0)
			sp->assocparams.sasoc_asocmaxrxt =
						assocparams->sasoc_asocmaxrxt;
		if (assocparams->sasoc_cookie_life != 0)
			sp->assocparams.sasoc_cookie_life =
						assocparams->sasoc_cookie_life;
	}
	return 0;
}


static int sctp_get_port(struct sock *sk, unsigned short snum)
{
	union sctp_addr addr;
	struct sctp_af *af = sctp_sk(sk)->pf->af;

	/* Set up a dummy address struct from the sk. */
	af->from_sk(&addr, sk);
	addr.v4.sin_port = htons(snum);

	/* Note: sk->sk_num gets filled in if ephemeral port request. */
	return sctp_get_port_local(sk, &addr);
}


static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
				    char __user *optval, int __user *optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	struct sctp_hmacalgo  __user *p = (void __user *)optval;
	struct sctp_hmac_algo_param *hmacs;
	__u16 data_len = 0;
	u32 num_idents;
	int i;

	if (!ep->auth_enable)
		return -EACCES;

	hmacs = ep->auth_hmacs_list;
	data_len = ntohs(hmacs->param_hdr.length) -
		   sizeof(struct sctp_paramhdr);

	if (len < sizeof(struct sctp_hmacalgo) + data_len)
		return -EINVAL;

	len = sizeof(struct sctp_hmacalgo) + data_len;
	num_idents = data_len / sizeof(u16);

	if (put_user(len, optlen))
		return -EFAULT;
	if (put_user(num_idents, &p->shmac_num_idents))
		return -EFAULT;
	for (i = 0; i < num_idents; i++) {
		__u16 hmacid = ntohs(hmacs->hmac_ids[i]);

		if (copy_to_user(&p->shmac_idents[i], &hmacid, sizeof(__u16)))
			return -EFAULT;
	}
	return 0;
}


struct sctp_transport *sctp_transport_get_next(struct net *net,
					       struct rhashtable_iter *iter)
{
	struct sctp_transport *t;

	t = rhashtable_walk_next(iter);
	for (; t; t = rhashtable_walk_next(iter)) {
		if (IS_ERR(t)) {
			if (PTR_ERR(t) == -EAGAIN)
				continue;
			break;
		}

		if (!sctp_transport_hold(t))
			continue;

		if (net_eq(t->asoc->base.net, net) &&
		    t->asoc->peer.primary_path == t)
			break;

		sctp_transport_put(t);
	}

	return t;
}


static void __sctp_write_space(struct sctp_association *asoc)
{
	struct sock *sk = asoc->base.sk;

	if (sctp_wspace(asoc) <= 0)
		return;

	if (waitqueue_active(&asoc->wait))
		wake_up_interruptible(&asoc->wait);

	if (sctp_writeable(sk)) {
		struct socket_wq *wq;

		rcu_read_lock();
		wq = rcu_dereference(sk->sk_wq);
		if (wq) {
			if (waitqueue_active(&wq->wait))
				wake_up_interruptible(&wq->wait);

			/* Note that we try to include the Async I/O support
			 * here by modeling from the current TCP/UDP code.
			 * We have not tested with it yet.
			 */
			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
				sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT);
		}
		rcu_read_unlock();
	}
}


static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
					union sctp_addr *addr, int len)
{
	struct sctp_af *af;

	/* Check minimum size.  */
	if (len < sizeof (struct sockaddr))
		return NULL;

	if (!opt->pf->af_supported(addr->sa.sa_family, opt))
		return NULL;

	if (addr->sa.sa_family == AF_INET6) {
		if (len < SIN6_LEN_RFC2133)
			return NULL;
		/* V4 mapped address are really of AF_INET family */
		if (ipv6_addr_v4mapped(&addr->v6.sin6_addr) &&
		    !opt->pf->af_supported(AF_INET, opt))
			return NULL;
	}

	/* If we get this far, af is valid. */
	af = sctp_get_af_specific(addr->sa.sa_family);

	if (len < af->sockaddr_len)
		return NULL;

	return af;
}


static int sctp_setsockopt_maxseg(struct sock *sk,
				  struct sctp_assoc_value *params,
				  unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;
	sctp_assoc_t assoc_id;
	int val;

	if (optlen == sizeof(int)) {
		pr_warn_ratelimited(DEPRECATED
				    "%s (pid %d) "
				    "Use of int in maxseg socket option.\n"
				    "Use struct sctp_assoc_value instead\n",
				    current->comm, task_pid_nr(current));
		assoc_id = SCTP_FUTURE_ASSOC;
		val = *(int *)params;
	} else if (optlen == sizeof(struct sctp_assoc_value)) {
		assoc_id = params->assoc_id;
		val = params->assoc_value;
	} else {
		return -EINVAL;
	}

	asoc = sctp_id2assoc(sk, assoc_id);
	if (!asoc && assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (val) {
		int min_len, max_len;
		__u16 datasize = asoc ? sctp_datachk_len(&asoc->stream) :
				 sizeof(struct sctp_data_chunk);

		min_len = sctp_min_frag_point(sp, datasize);
		max_len = SCTP_MAX_CHUNK_LEN - datasize;

		if (val < min_len || val > max_len)
			return -EINVAL;
	}

	if (asoc) {
		asoc->user_frag = val;
		sctp_assoc_update_frag_point(asoc);
	} else {
		sp->user_frag = val;
	}

	return 0;
}


static int sctp_setsockopt_asconf_supported(struct sock *sk,
					    struct sctp_assoc_value *params,
					    unsigned int optlen)
{
	struct sctp_association *asoc;
	struct sctp_endpoint *ep;
	int retval = -EINVAL;

	if (optlen != sizeof(*params))
		goto out;

	asoc = sctp_id2assoc(sk, params->assoc_id);
	if (!asoc && params->assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		goto out;

	ep = sctp_sk(sk)->ep;
	ep->asconf_enable = !!params->assoc_value;

	if (ep->asconf_enable && ep->auth_enable) {
		sctp_auth_ep_add_chunkid(ep, SCTP_CID_ASCONF);
		sctp_auth_ep_add_chunkid(ep, SCTP_CID_ASCONF_ACK);
	}

	retval = 0;

out:
	return retval;
}


static int sctp_setsockopt_adaptation_layer(struct sock *sk,
					    struct sctp_setadaptation *adapt,
					    unsigned int optlen)
{
	if (optlen != sizeof(struct sctp_setadaptation))
		return -EINVAL;

	sctp_sk(sk)->adaptation_ind = adapt->ssb_adaptation_ind;

	return 0;
}


static int sctp_getsockopt_enable_strreset(struct sock *sk, int len,
					   char __user *optval,
					   int __user *optlen)
{
	struct sctp_assoc_value params;
	struct sctp_association *asoc;
	int retval = -EFAULT;

	if (len < sizeof(params)) {
		retval = -EINVAL;
		goto out;
	}

	len = sizeof(params);
	if (copy_from_user(&params, optval, len))
		goto out;

	asoc = sctp_id2assoc(sk, params.assoc_id);
	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		retval = -EINVAL;
		goto out;
	}

	params.assoc_value = asoc ? asoc->strreset_enable
				  : sctp_sk(sk)->ep->strreset_enable;

	if (put_user(len, optlen))
		goto out;

	if (copy_to_user(optval, &params, len))
		goto out;

	retval = 0;

out:
	return retval;
}


static int sctp_sendmsg_check_sflags(struct sctp_association *asoc,
				     __u16 sflags, struct msghdr *msg,
				     size_t msg_len)
{
	struct sock *sk = asoc->base.sk;
	struct net *net = sock_net(sk);

	if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP))
		return -EPIPE;

	if ((sflags & SCTP_SENDALL) && sctp_style(sk, UDP) &&
	    !sctp_state(asoc, ESTABLISHED))
		return 0;

	if (sflags & SCTP_EOF) {
		pr_debug("%s: shutting down association:%p\n", __func__, asoc);
		sctp_primitive_SHUTDOWN(net, asoc, NULL);

		return 0;
	}

	if (sflags & SCTP_ABORT) {
		struct sctp_chunk *chunk;

		chunk = sctp_make_abort_user(asoc, msg, msg_len);
		if (!chunk)
			return -ENOMEM;

		pr_debug("%s: aborting association:%p\n", __func__, asoc);
		sctp_primitive_ABORT(net, asoc, chunk);
		iov_iter_revert(&msg->msg_iter, msg_len);

		return 0;
	}

	return 1;
}


static int sctp_setsockopt_hmac_ident(struct sock *sk,
				      struct sctp_hmacalgo *hmacs,
				      unsigned int optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	u32 idents;

	if (!ep->auth_enable)
		return -EACCES;

	if (optlen < sizeof(struct sctp_hmacalgo))
		return -EINVAL;
	optlen = min_t(unsigned int, optlen, sizeof(struct sctp_hmacalgo) +
					     SCTP_AUTH_NUM_HMACS * sizeof(u16));

	idents = hmacs->shmac_num_idents;
	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo)))
		return -EINVAL;

	return sctp_auth_ep_set_hmacs(ep, hmacs);
}


int sctp_inet_listen(struct socket *sock, int backlog)
{
	struct sock *sk = sock->sk;
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	int err = -EINVAL;

	if (unlikely(backlog < 0))
		return err;

	lock_sock(sk);

	/* Peeled-off sockets are not allowed to listen().  */
	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
		goto out;

	if (sock->state != SS_UNCONNECTED)
		goto out;

	if (!sctp_sstate(sk, LISTENING) && !sctp_sstate(sk, CLOSED))
		goto out;

	/* If backlog is zero, disable listening. */
	if (!backlog) {
		if (sctp_sstate(sk, CLOSED))
			goto out;

		err = 0;
		sctp_unhash_endpoint(ep);
		sk->sk_state = SCTP_SS_CLOSED;
		if (sk->sk_reuse || sctp_sk(sk)->reuse)
			sctp_sk(sk)->bind_hash->fastreuse = 1;
		goto out;
	}

	/* If we are already listening, just update the backlog */
	if (sctp_sstate(sk, LISTENING))
		WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
	else {
		err = sctp_listen_start(sk, backlog);
		if (err)
			goto out;
	}

	err = 0;
out:
	release_sock(sk);
	return err;
}


static int sctp_getsockopt_default_send_param(struct sock *sk,
					int len, char __user *optval,
					int __user *optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;
	struct sctp_sndrcvinfo info;

	if (len < sizeof(info))
		return -EINVAL;

	len = sizeof(info);

	if (copy_from_user(&info, optval, len))
		return -EFAULT;

	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
	if (!asoc && info.sinfo_assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		info.sinfo_stream = asoc->default_stream;
		info.sinfo_flags = asoc->default_flags;
		info.sinfo_ppid = asoc->default_ppid;
		info.sinfo_context = asoc->default_context;
		info.sinfo_timetolive = asoc->default_timetolive;
	} else {
		info.sinfo_stream = sp->default_stream;
		info.sinfo_flags = sp->default_flags;
		info.sinfo_ppid = sp->default_ppid;
		info.sinfo_context = sp->default_context;
		info.sinfo_timetolive = sp->default_timetolive;
	}

	if (put_user(len, optlen))
		return -EFAULT;
	if (copy_to_user(optval, &info, len))
		return -EFAULT;

	return 0;
}


static int sctp_setsockopt_del_key(struct sock *sk,
				   struct sctp_authkeyid *val,
				   unsigned int optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	struct sctp_association *asoc;
	int ret = 0;

	if (optlen != sizeof(struct sctp_authkeyid))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, val->scact_assoc_id);
	if (!asoc && val->scact_assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc)
		return sctp_auth_del_key_id(ep, asoc, val->scact_keynumber);

	if (sctp_style(sk, TCP))
		val->scact_assoc_id = SCTP_FUTURE_ASSOC;

	if (val->scact_assoc_id == SCTP_FUTURE_ASSOC ||
	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
		ret = sctp_auth_del_key_id(ep, asoc, val->scact_keynumber);
		if (ret)
			return ret;
	}

	if (val->scact_assoc_id == SCTP_CURRENT_ASSOC ||
	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
		list_for_each_entry(asoc, &ep->asocs, asocs) {
			int res = sctp_auth_del_key_id(ep, asoc,
						       val->scact_keynumber);

			if (res && !ret)
				ret = res;
		}
	}

	return ret;
}


static union sctp_addr *sctp_sendmsg_get_daddr(struct sock *sk,
					       const struct msghdr *msg,
					       struct sctp_cmsgs *cmsgs)
{
	union sctp_addr *daddr = NULL;
	int err;

	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
		int len = msg->msg_namelen;

		if (len > sizeof(*daddr))
			len = sizeof(*daddr);

		daddr = (union sctp_addr *)msg->msg_name;

		err = sctp_verify_addr(sk, daddr, len);
		if (err)
			return ERR_PTR(err);
	}

	return daddr;
}


static int sctp_setsockopt_active_key(struct sock *sk,
				      struct sctp_authkeyid *val,
				      unsigned int optlen)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	struct sctp_association *asoc;
	int ret = 0;

	if (optlen != sizeof(struct sctp_authkeyid))
		return -EINVAL;

	asoc = sctp_id2assoc(sk, val->scact_assoc_id);
	if (!asoc && val->scact_assoc_id > SCTP_ALL_ASSOC &&
	    sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc)
		return sctp_auth_set_active_key(ep, asoc, val->scact_keynumber);

	if (sctp_style(sk, TCP))
		val->scact_assoc_id = SCTP_FUTURE_ASSOC;

	if (val->scact_assoc_id == SCTP_FUTURE_ASSOC ||
	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
		ret = sctp_auth_set_active_key(ep, asoc, val->scact_keynumber);
		if (ret)
			return ret;
	}

	if (val->scact_assoc_id == SCTP_CURRENT_ASSOC ||
	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
		list_for_each_entry(asoc, &ep->asocs, asocs) {
			int res = sctp_auth_set_active_key(ep, asoc,
							   val->scact_keynumber);

			if (res && !ret)
				ret = res;
		}
	}

	return ret;
}


static int sctp_getsockopt_pr_supported(struct sock *sk, int len,
					char __user *optval,
					int __user *optlen)
{
	struct sctp_assoc_value params;
	struct sctp_association *asoc;
	int retval = -EFAULT;

	if (len < sizeof(params)) {
		retval = -EINVAL;
		goto out;
	}

	len = sizeof(params);
	if (copy_from_user(&params, optval, len))
		goto out;

	asoc = sctp_id2assoc(sk, params.assoc_id);
	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
	    sctp_style(sk, UDP)) {
		retval = -EINVAL;
		goto out;
	}

	params.assoc_value = asoc ? asoc->peer.prsctp_capable
				  : sctp_sk(sk)->ep->prsctp_enable;

	if (put_user(len, optlen))
		goto out;

	if (copy_to_user(optval, &params, len))
		goto out;

	retval = 0;

out:
	return retval;
}


static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
{
	struct net *net = sock_net(sk);
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_endpoint *ep = sp->ep;
	struct sctp_bind_addr *bp = &ep->base.bind_addr;
	struct sctp_af *af;
	unsigned short snum;
	int ret = 0;

	/* Common sockaddr verification. */
	af = sctp_sockaddr_af(sp, addr, len);
	if (!af) {
		pr_debug("%s: sk:%p, newaddr:%p, len:%d EINVAL\n",
			 __func__, sk, addr, len);
		return -EINVAL;
	}

	snum = ntohs(addr->v4.sin_port);

	pr_debug("%s: sk:%p, new addr:%pISc, port:%d, new port:%d, len:%d\n",
		 __func__, sk, &addr->sa, bp->port, snum, len);

	/* PF specific bind() address verification. */
	if (!sp->pf->bind_verify(sp, addr))
		return -EADDRNOTAVAIL;

	/* We must either be unbound, or bind to the same port.
	 * It's OK to allow 0 ports if we are already bound.
	 * We'll just inhert an already bound port in this case
	 */
	if (bp->port) {
		if (!snum)
			snum = bp->port;
		else if (snum != bp->port) {
			pr_debug("%s: new port %d doesn't match existing port "
				 "%d\n", __func__, snum, bp->port);
			return -EINVAL;
		}
	}

	if (snum && inet_port_requires_bind_service(net, snum) &&
	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
		return -EACCES;

	/* See if the address matches any of the addresses we may have
	 * already bound before checking against other endpoints.
	 */
	if (sctp_bind_addr_match(bp, addr, sp))
		return -EINVAL;

	/* Make sure we are allowed to bind here.
	 * The function sctp_get_port_local() does duplicate address
	 * detection.
	 */
	addr->v4.sin_port = htons(snum);
	if (sctp_get_port_local(sk, addr))
		return -EADDRINUSE;

	/* Refresh ephemeral port.  */
	if (!bp->port)
		bp->port = inet_sk(sk)->inet_num;

	/* Add the address to the bind address list.
	 * Use GFP_ATOMIC since BHs will be disabled.
	 */
	ret = sctp_add_bind_addr(bp, addr, af->sockaddr_len,
				 SCTP_ADDR_SRC, GFP_ATOMIC);

	if (ret) {
		sctp_put_port(sk);
		return ret;
	}
	/* Copy back into socket for getsockname() use. */
	inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
	sp->pf->to_sk_saddr(addr, sk);

	return ret;
}


static int sctp_setsockopt_delayed_ack(struct sock *sk,
				       struct sctp_sack_info *params,
				       unsigned int optlen)
{
	if (optlen == sizeof(struct sctp_assoc_value)) {
		struct sctp_assoc_value *v = (struct sctp_assoc_value *)params;
		struct sctp_sack_info p;

		pr_warn_ratelimited(DEPRECATED
				    "%s (pid %d) "
				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
				    "Use struct sctp_sack_info instead\n",
				    current->comm, task_pid_nr(current));

		p.sack_assoc_id = v->assoc_id;
		p.sack_delay = v->assoc_value;
		p.sack_freq = v->assoc_value ? 0 : 1;
		return __sctp_setsockopt_delayed_ack(sk, &p);
	}

	if (optlen != sizeof(struct sctp_sack_info))
		return -EINVAL;
	if (params->sack_delay == 0 && params->sack_freq == 0)
		return 0;
	return __sctp_setsockopt_delayed_ack(sk, params);
}