xref: /linux/net/tipc/socket.c (revision 71dfa617ea9f18e4585fe78364217cd32b1fc382)
1 /*
2  * net/tipc/socket.c: TIPC socket API
3  *
4  * Copyright (c) 2001-2007, 2012-2019, Ericsson AB
5  * Copyright (c) 2004-2008, 2010-2013, Wind River Systems
6  * Copyright (c) 2020-2021, Red Hat Inc
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the names of the copyright holders nor the names of its
18  *    contributors may be used to endorse or promote products derived from
19  *    this software without specific prior written permission.
20  *
21  * Alternatively, this software may be distributed under the terms of the
22  * GNU General Public License ("GPL") version 2 as published by the Free
23  * Software Foundation.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include <linux/rhashtable.h>
39 #include <linux/sched/signal.h>
40 #include <trace/events/sock.h>
41 
42 #include "core.h"
43 #include "name_table.h"
44 #include "node.h"
45 #include "link.h"
46 #include "name_distr.h"
47 #include "socket.h"
48 #include "bcast.h"
49 #include "netlink.h"
50 #include "group.h"
51 #include "trace.h"
52 
53 #define NAGLE_START_INIT	4
54 #define NAGLE_START_MAX		1024
55 #define CONN_TIMEOUT_DEFAULT    8000    /* default connect timeout = 8s */
56 #define CONN_PROBING_INTV	msecs_to_jiffies(3600000)  /* [ms] => 1 h */
57 #define TIPC_MAX_PORT		0xffffffff
58 #define TIPC_MIN_PORT		1
59 #define TIPC_ACK_RATE		4       /* ACK at 1/4 of rcv window size */
60 
61 enum {
62 	TIPC_LISTEN = TCP_LISTEN,
63 	TIPC_ESTABLISHED = TCP_ESTABLISHED,
64 	TIPC_OPEN = TCP_CLOSE,
65 	TIPC_DISCONNECTING = TCP_CLOSE_WAIT,
66 	TIPC_CONNECTING = TCP_SYN_SENT,
67 };
68 
69 struct sockaddr_pair {
70 	struct sockaddr_tipc sock;
71 	struct sockaddr_tipc member;
72 };
73 
74 /**
75  * struct tipc_sock - TIPC socket structure
76  * @sk: socket - interacts with 'port' and with user via the socket API
77  * @max_pkt: maximum packet size "hint" used when building messages sent by port
78  * @maxnagle: maximum size of msg which can be subject to nagle
79  * @portid: unique port identity in TIPC socket hash table
80  * @phdr: preformatted message header used when sending messages
81  * @cong_links: list of congested links
82  * @publications: list of publications for port
83  * @pub_count: total # of publications port has made during its lifetime
84  * @conn_timeout: the time we can wait for an unresponded setup request
85  * @probe_unacked: probe has not received ack yet
86  * @dupl_rcvcnt: number of bytes counted twice, in both backlog and rcv queue
87  * @cong_link_cnt: number of congested links
88  * @snt_unacked: # messages sent by socket, and not yet acked by peer
89  * @snd_win: send window size
90  * @peer_caps: peer capabilities mask
91  * @rcv_unacked: # messages read by user, but not yet acked back to peer
92  * @rcv_win: receive window size
93  * @peer: 'connected' peer for dgram/rdm
94  * @node: hash table node
95  * @mc_method: cookie for use between socket and broadcast layer
96  * @rcu: rcu struct for tipc_sock
97  * @group: TIPC communications group
98  * @oneway: message count in one direction (FIXME)
99  * @nagle_start: current nagle value
100  * @snd_backlog: send backlog count
101  * @msg_acc: messages accepted; used in managing backlog and nagle
102  * @pkt_cnt: TIPC socket packet count
103  * @expect_ack: whether this TIPC socket is expecting an ack
104  * @nodelay: setsockopt() TIPC_NODELAY setting
105  * @group_is_open: TIPC socket group is fully open (FIXME)
106  * @published: true if port has one or more associated names
107  * @conn_addrtype: address type used when establishing connection
108  */
109 struct tipc_sock {
110 	struct sock sk;
111 	u32 max_pkt;
112 	u32 maxnagle;
113 	u32 portid;
114 	struct tipc_msg phdr;
115 	struct list_head cong_links;
116 	struct list_head publications;
117 	u32 pub_count;
118 	atomic_t dupl_rcvcnt;
119 	u16 conn_timeout;
120 	bool probe_unacked;
121 	u16 cong_link_cnt;
122 	u16 snt_unacked;
123 	u16 snd_win;
124 	u16 peer_caps;
125 	u16 rcv_unacked;
126 	u16 rcv_win;
127 	struct sockaddr_tipc peer;
128 	struct rhash_head node;
129 	struct tipc_mc_method mc_method;
130 	struct rcu_head rcu;
131 	struct tipc_group *group;
132 	u32 oneway;
133 	u32 nagle_start;
134 	u16 snd_backlog;
135 	u16 msg_acc;
136 	u16 pkt_cnt;
137 	bool expect_ack;
138 	bool nodelay;
139 	bool group_is_open;
140 	bool published;
141 	u8 conn_addrtype;
142 };
143 
144 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
145 static void tipc_data_ready(struct sock *sk);
146 static void tipc_write_space(struct sock *sk);
147 static void tipc_sock_destruct(struct sock *sk);
148 static int tipc_release(struct socket *sock);
149 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
150 		       bool kern);
151 static void tipc_sk_timeout(struct timer_list *t);
152 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua);
153 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua);
154 static int tipc_sk_leave(struct tipc_sock *tsk);
155 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid);
156 static int tipc_sk_insert(struct tipc_sock *tsk);
157 static void tipc_sk_remove(struct tipc_sock *tsk);
158 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz);
159 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz);
160 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack);
161 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p);
162 
163 static const struct proto_ops packet_ops;
164 static const struct proto_ops stream_ops;
165 static const struct proto_ops msg_ops;
166 static struct proto tipc_proto;
167 static const struct rhashtable_params tsk_rht_params;
168 
169 static u32 tsk_own_node(struct tipc_sock *tsk)
170 {
171 	return msg_prevnode(&tsk->phdr);
172 }
173 
174 static u32 tsk_peer_node(struct tipc_sock *tsk)
175 {
176 	return msg_destnode(&tsk->phdr);
177 }
178 
179 static u32 tsk_peer_port(struct tipc_sock *tsk)
180 {
181 	return msg_destport(&tsk->phdr);
182 }
183 
184 static  bool tsk_unreliable(struct tipc_sock *tsk)
185 {
186 	return msg_src_droppable(&tsk->phdr) != 0;
187 }
188 
189 static void tsk_set_unreliable(struct tipc_sock *tsk, bool unreliable)
190 {
191 	msg_set_src_droppable(&tsk->phdr, unreliable ? 1 : 0);
192 }
193 
194 static bool tsk_unreturnable(struct tipc_sock *tsk)
195 {
196 	return msg_dest_droppable(&tsk->phdr) != 0;
197 }
198 
199 static void tsk_set_unreturnable(struct tipc_sock *tsk, bool unreturnable)
200 {
201 	msg_set_dest_droppable(&tsk->phdr, unreturnable ? 1 : 0);
202 }
203 
204 static int tsk_importance(struct tipc_sock *tsk)
205 {
206 	return msg_importance(&tsk->phdr);
207 }
208 
209 static struct tipc_sock *tipc_sk(const struct sock *sk)
210 {
211 	return container_of(sk, struct tipc_sock, sk);
212 }
213 
214 int tsk_set_importance(struct sock *sk, int imp)
215 {
216 	if (imp > TIPC_CRITICAL_IMPORTANCE)
217 		return -EINVAL;
218 	msg_set_importance(&tipc_sk(sk)->phdr, (u32)imp);
219 	return 0;
220 }
221 
222 static bool tsk_conn_cong(struct tipc_sock *tsk)
223 {
224 	return tsk->snt_unacked > tsk->snd_win;
225 }
226 
227 static u16 tsk_blocks(int len)
228 {
229 	return ((len / FLOWCTL_BLK_SZ) + 1);
230 }
231 
232 /* tsk_blocks(): translate a buffer size in bytes to number of
233  * advertisable blocks, taking into account the ratio truesize(len)/len
234  * We can trust that this ratio is always < 4 for len >= FLOWCTL_BLK_SZ
235  */
236 static u16 tsk_adv_blocks(int len)
237 {
238 	return len / FLOWCTL_BLK_SZ / 4;
239 }
240 
241 /* tsk_inc(): increment counter for sent or received data
242  * - If block based flow control is not supported by peer we
243  *   fall back to message based ditto, incrementing the counter
244  */
245 static u16 tsk_inc(struct tipc_sock *tsk, int msglen)
246 {
247 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
248 		return ((msglen / FLOWCTL_BLK_SZ) + 1);
249 	return 1;
250 }
251 
252 /* tsk_set_nagle - enable/disable nagle property by manipulating maxnagle
253  */
254 static void tsk_set_nagle(struct tipc_sock *tsk)
255 {
256 	struct sock *sk = &tsk->sk;
257 
258 	tsk->maxnagle = 0;
259 	if (sk->sk_type != SOCK_STREAM)
260 		return;
261 	if (tsk->nodelay)
262 		return;
263 	if (!(tsk->peer_caps & TIPC_NAGLE))
264 		return;
265 	/* Limit node local buffer size to avoid receive queue overflow */
266 	if (tsk->max_pkt == MAX_MSG_SIZE)
267 		tsk->maxnagle = 1500;
268 	else
269 		tsk->maxnagle = tsk->max_pkt;
270 }
271 
272 /**
273  * tsk_advance_rx_queue - discard first buffer in socket receive queue
274  * @sk: network socket
275  *
276  * Caller must hold socket lock
277  */
278 static void tsk_advance_rx_queue(struct sock *sk)
279 {
280 	trace_tipc_sk_advance_rx(sk, NULL, TIPC_DUMP_SK_RCVQ, " ");
281 	kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
282 }
283 
284 /* tipc_sk_respond() : send response message back to sender
285  */
286 static void tipc_sk_respond(struct sock *sk, struct sk_buff *skb, int err)
287 {
288 	u32 selector;
289 	u32 dnode;
290 	u32 onode = tipc_own_addr(sock_net(sk));
291 
292 	if (!tipc_msg_reverse(onode, &skb, err))
293 		return;
294 
295 	trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE, "@sk_respond!");
296 	dnode = msg_destnode(buf_msg(skb));
297 	selector = msg_origport(buf_msg(skb));
298 	tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector);
299 }
300 
301 /**
302  * tsk_rej_rx_queue - reject all buffers in socket receive queue
303  * @sk: network socket
304  * @error: response error code
305  *
306  * Caller must hold socket lock
307  */
308 static void tsk_rej_rx_queue(struct sock *sk, int error)
309 {
310 	struct sk_buff *skb;
311 
312 	while ((skb = __skb_dequeue(&sk->sk_receive_queue)))
313 		tipc_sk_respond(sk, skb, error);
314 }
315 
316 static bool tipc_sk_connected(const struct sock *sk)
317 {
318 	return READ_ONCE(sk->sk_state) == TIPC_ESTABLISHED;
319 }
320 
321 /* tipc_sk_type_connectionless - check if the socket is datagram socket
322  * @sk: socket
323  *
324  * Returns true if connection less, false otherwise
325  */
326 static bool tipc_sk_type_connectionless(struct sock *sk)
327 {
328 	return sk->sk_type == SOCK_RDM || sk->sk_type == SOCK_DGRAM;
329 }
330 
331 /* tsk_peer_msg - verify if message was sent by connected port's peer
332  *
333  * Handles cases where the node's network address has changed from
334  * the default of <0.0.0> to its configured setting.
335  */
336 static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg)
337 {
338 	struct sock *sk = &tsk->sk;
339 	u32 self = tipc_own_addr(sock_net(sk));
340 	u32 peer_port = tsk_peer_port(tsk);
341 	u32 orig_node, peer_node;
342 
343 	if (unlikely(!tipc_sk_connected(sk)))
344 		return false;
345 
346 	if (unlikely(msg_origport(msg) != peer_port))
347 		return false;
348 
349 	orig_node = msg_orignode(msg);
350 	peer_node = tsk_peer_node(tsk);
351 
352 	if (likely(orig_node == peer_node))
353 		return true;
354 
355 	if (!orig_node && peer_node == self)
356 		return true;
357 
358 	if (!peer_node && orig_node == self)
359 		return true;
360 
361 	return false;
362 }
363 
364 /* tipc_set_sk_state - set the sk_state of the socket
365  * @sk: socket
366  *
367  * Caller must hold socket lock
368  *
369  * Returns 0 on success, errno otherwise
370  */
371 static int tipc_set_sk_state(struct sock *sk, int state)
372 {
373 	int oldsk_state = sk->sk_state;
374 	int res = -EINVAL;
375 
376 	switch (state) {
377 	case TIPC_OPEN:
378 		res = 0;
379 		break;
380 	case TIPC_LISTEN:
381 	case TIPC_CONNECTING:
382 		if (oldsk_state == TIPC_OPEN)
383 			res = 0;
384 		break;
385 	case TIPC_ESTABLISHED:
386 		if (oldsk_state == TIPC_CONNECTING ||
387 		    oldsk_state == TIPC_OPEN)
388 			res = 0;
389 		break;
390 	case TIPC_DISCONNECTING:
391 		if (oldsk_state == TIPC_CONNECTING ||
392 		    oldsk_state == TIPC_ESTABLISHED)
393 			res = 0;
394 		break;
395 	}
396 
397 	if (!res)
398 		sk->sk_state = state;
399 
400 	return res;
401 }
402 
403 static int tipc_sk_sock_err(struct socket *sock, long *timeout)
404 {
405 	struct sock *sk = sock->sk;
406 	int err = sock_error(sk);
407 	int typ = sock->type;
408 
409 	if (err)
410 		return err;
411 	if (typ == SOCK_STREAM || typ == SOCK_SEQPACKET) {
412 		if (sk->sk_state == TIPC_DISCONNECTING)
413 			return -EPIPE;
414 		else if (!tipc_sk_connected(sk))
415 			return -ENOTCONN;
416 	}
417 	if (!*timeout)
418 		return -EAGAIN;
419 	if (signal_pending(current))
420 		return sock_intr_errno(*timeout);
421 
422 	return 0;
423 }
424 
425 #define tipc_wait_for_cond(sock_, timeo_, condition_)			       \
426 ({                                                                             \
427 	DEFINE_WAIT_FUNC(wait_, woken_wake_function);                          \
428 	struct sock *sk_;						       \
429 	int rc_;							       \
430 									       \
431 	while ((rc_ = !(condition_))) {					       \
432 		/* coupled with smp_wmb() in tipc_sk_proto_rcv() */            \
433 		smp_rmb();                                                     \
434 		sk_ = (sock_)->sk;					       \
435 		rc_ = tipc_sk_sock_err((sock_), timeo_);		       \
436 		if (rc_)						       \
437 			break;						       \
438 		add_wait_queue(sk_sleep(sk_), &wait_);                         \
439 		release_sock(sk_);					       \
440 		*(timeo_) = wait_woken(&wait_, TASK_INTERRUPTIBLE, *(timeo_)); \
441 		sched_annotate_sleep();				               \
442 		lock_sock(sk_);						       \
443 		remove_wait_queue(sk_sleep(sk_), &wait_);		       \
444 	}								       \
445 	rc_;								       \
446 })
447 
448 /**
449  * tipc_sk_create - create a TIPC socket
450  * @net: network namespace (must be default network)
451  * @sock: pre-allocated socket structure
452  * @protocol: protocol indicator (must be 0)
453  * @kern: caused by kernel or by userspace?
454  *
455  * This routine creates additional data structures used by the TIPC socket,
456  * initializes them, and links them together.
457  *
458  * Return: 0 on success, errno otherwise
459  */
460 static int tipc_sk_create(struct net *net, struct socket *sock,
461 			  int protocol, int kern)
462 {
463 	const struct proto_ops *ops;
464 	struct sock *sk;
465 	struct tipc_sock *tsk;
466 	struct tipc_msg *msg;
467 
468 	/* Validate arguments */
469 	if (unlikely(protocol != 0))
470 		return -EPROTONOSUPPORT;
471 
472 	switch (sock->type) {
473 	case SOCK_STREAM:
474 		ops = &stream_ops;
475 		break;
476 	case SOCK_SEQPACKET:
477 		ops = &packet_ops;
478 		break;
479 	case SOCK_DGRAM:
480 	case SOCK_RDM:
481 		ops = &msg_ops;
482 		break;
483 	default:
484 		return -EPROTOTYPE;
485 	}
486 
487 	/* Allocate socket's protocol area */
488 	sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto, kern);
489 	if (sk == NULL)
490 		return -ENOMEM;
491 
492 	tsk = tipc_sk(sk);
493 	tsk->max_pkt = MAX_PKT_DEFAULT;
494 	tsk->maxnagle = 0;
495 	tsk->nagle_start = NAGLE_START_INIT;
496 	INIT_LIST_HEAD(&tsk->publications);
497 	INIT_LIST_HEAD(&tsk->cong_links);
498 	msg = &tsk->phdr;
499 
500 	/* Finish initializing socket data structures */
501 	sock->ops = ops;
502 	sock_init_data(sock, sk);
503 	tipc_set_sk_state(sk, TIPC_OPEN);
504 	if (tipc_sk_insert(tsk)) {
505 		sk_free(sk);
506 		pr_warn("Socket create failed; port number exhausted\n");
507 		return -EINVAL;
508 	}
509 
510 	/* Ensure tsk is visible before we read own_addr. */
511 	smp_mb();
512 
513 	tipc_msg_init(tipc_own_addr(net), msg, TIPC_LOW_IMPORTANCE,
514 		      TIPC_NAMED_MSG, NAMED_H_SIZE, 0);
515 
516 	msg_set_origport(msg, tsk->portid);
517 	timer_setup(&sk->sk_timer, tipc_sk_timeout, 0);
518 	sk->sk_shutdown = 0;
519 	sk->sk_backlog_rcv = tipc_sk_backlog_rcv;
520 	sk->sk_rcvbuf = READ_ONCE(sysctl_tipc_rmem[1]);
521 	sk->sk_data_ready = tipc_data_ready;
522 	sk->sk_write_space = tipc_write_space;
523 	sk->sk_destruct = tipc_sock_destruct;
524 	tsk->conn_timeout = CONN_TIMEOUT_DEFAULT;
525 	tsk->group_is_open = true;
526 	atomic_set(&tsk->dupl_rcvcnt, 0);
527 
528 	/* Start out with safe limits until we receive an advertised window */
529 	tsk->snd_win = tsk_adv_blocks(RCVBUF_MIN);
530 	tsk->rcv_win = tsk->snd_win;
531 
532 	if (tipc_sk_type_connectionless(sk)) {
533 		tsk_set_unreturnable(tsk, true);
534 		if (sock->type == SOCK_DGRAM)
535 			tsk_set_unreliable(tsk, true);
536 	}
537 	__skb_queue_head_init(&tsk->mc_method.deferredq);
538 	trace_tipc_sk_create(sk, NULL, TIPC_DUMP_NONE, " ");
539 	return 0;
540 }
541 
542 static void tipc_sk_callback(struct rcu_head *head)
543 {
544 	struct tipc_sock *tsk = container_of(head, struct tipc_sock, rcu);
545 
546 	sock_put(&tsk->sk);
547 }
548 
549 /* Caller should hold socket lock for the socket. */
550 static void __tipc_shutdown(struct socket *sock, int error)
551 {
552 	struct sock *sk = sock->sk;
553 	struct tipc_sock *tsk = tipc_sk(sk);
554 	struct net *net = sock_net(sk);
555 	long timeout = msecs_to_jiffies(CONN_TIMEOUT_DEFAULT);
556 	u32 dnode = tsk_peer_node(tsk);
557 	struct sk_buff *skb;
558 
559 	/* Avoid that hi-prio shutdown msgs bypass msgs in link wakeup queue */
560 	tipc_wait_for_cond(sock, &timeout, (!tsk->cong_link_cnt &&
561 					    !tsk_conn_cong(tsk)));
562 
563 	/* Push out delayed messages if in Nagle mode */
564 	tipc_sk_push_backlog(tsk, false);
565 	/* Remove pending SYN */
566 	__skb_queue_purge(&sk->sk_write_queue);
567 
568 	/* Remove partially received buffer if any */
569 	skb = skb_peek(&sk->sk_receive_queue);
570 	if (skb && TIPC_SKB_CB(skb)->bytes_read) {
571 		__skb_unlink(skb, &sk->sk_receive_queue);
572 		kfree_skb(skb);
573 	}
574 
575 	/* Reject all unreceived messages if connectionless */
576 	if (tipc_sk_type_connectionless(sk)) {
577 		tsk_rej_rx_queue(sk, error);
578 		return;
579 	}
580 
581 	switch (sk->sk_state) {
582 	case TIPC_CONNECTING:
583 	case TIPC_ESTABLISHED:
584 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
585 		tipc_node_remove_conn(net, dnode, tsk->portid);
586 		/* Send a FIN+/- to its peer */
587 		skb = __skb_dequeue(&sk->sk_receive_queue);
588 		if (skb) {
589 			__skb_queue_purge(&sk->sk_receive_queue);
590 			tipc_sk_respond(sk, skb, error);
591 			break;
592 		}
593 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
594 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode,
595 				      tsk_own_node(tsk), tsk_peer_port(tsk),
596 				      tsk->portid, error);
597 		if (skb)
598 			tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
599 		break;
600 	case TIPC_LISTEN:
601 		/* Reject all SYN messages */
602 		tsk_rej_rx_queue(sk, error);
603 		break;
604 	default:
605 		__skb_queue_purge(&sk->sk_receive_queue);
606 		break;
607 	}
608 }
609 
610 /**
611  * tipc_release - destroy a TIPC socket
612  * @sock: socket to destroy
613  *
614  * This routine cleans up any messages that are still queued on the socket.
615  * For DGRAM and RDM socket types, all queued messages are rejected.
616  * For SEQPACKET and STREAM socket types, the first message is rejected
617  * and any others are discarded.  (If the first message on a STREAM socket
618  * is partially-read, it is discarded and the next one is rejected instead.)
619  *
620  * NOTE: Rejected messages are not necessarily returned to the sender!  They
621  * are returned or discarded according to the "destination droppable" setting
622  * specified for the message by the sender.
623  *
624  * Return: 0 on success, errno otherwise
625  */
626 static int tipc_release(struct socket *sock)
627 {
628 	struct sock *sk = sock->sk;
629 	struct tipc_sock *tsk;
630 
631 	/*
632 	 * Exit if socket isn't fully initialized (occurs when a failed accept()
633 	 * releases a pre-allocated child socket that was never used)
634 	 */
635 	if (sk == NULL)
636 		return 0;
637 
638 	tsk = tipc_sk(sk);
639 	lock_sock(sk);
640 
641 	trace_tipc_sk_release(sk, NULL, TIPC_DUMP_ALL, " ");
642 	__tipc_shutdown(sock, TIPC_ERR_NO_PORT);
643 	sk->sk_shutdown = SHUTDOWN_MASK;
644 	tipc_sk_leave(tsk);
645 	tipc_sk_withdraw(tsk, NULL);
646 	__skb_queue_purge(&tsk->mc_method.deferredq);
647 	sk_stop_timer(sk, &sk->sk_timer);
648 	tipc_sk_remove(tsk);
649 
650 	sock_orphan(sk);
651 	/* Reject any messages that accumulated in backlog queue */
652 	release_sock(sk);
653 	tipc_dest_list_purge(&tsk->cong_links);
654 	tsk->cong_link_cnt = 0;
655 	call_rcu(&tsk->rcu, tipc_sk_callback);
656 	sock->sk = NULL;
657 
658 	return 0;
659 }
660 
661 /**
662  * __tipc_bind - associate or disassocate TIPC name(s) with a socket
663  * @sock: socket structure
664  * @skaddr: socket address describing name(s) and desired operation
665  * @alen: size of socket address data structure
666  *
667  * Name and name sequence binding are indicated using a positive scope value;
668  * a negative scope value unbinds the specified name.  Specifying no name
669  * (i.e. a socket address length of 0) unbinds all names from the socket.
670  *
671  * Return: 0 on success, errno otherwise
672  *
673  * NOTE: This routine doesn't need to take the socket lock since it doesn't
674  *       access any non-constant socket information.
675  */
676 static int __tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
677 {
678 	struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr;
679 	struct tipc_sock *tsk = tipc_sk(sock->sk);
680 	bool unbind = false;
681 
682 	if (unlikely(!alen))
683 		return tipc_sk_withdraw(tsk, NULL);
684 
685 	if (ua->addrtype == TIPC_SERVICE_ADDR) {
686 		ua->addrtype = TIPC_SERVICE_RANGE;
687 		ua->sr.upper = ua->sr.lower;
688 	}
689 	if (ua->scope < 0) {
690 		unbind = true;
691 		ua->scope = -ua->scope;
692 	}
693 	/* Users may still use deprecated TIPC_ZONE_SCOPE */
694 	if (ua->scope != TIPC_NODE_SCOPE)
695 		ua->scope = TIPC_CLUSTER_SCOPE;
696 
697 	if (tsk->group)
698 		return -EACCES;
699 
700 	if (unbind)
701 		return tipc_sk_withdraw(tsk, ua);
702 	return tipc_sk_publish(tsk, ua);
703 }
704 
705 int tipc_sk_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
706 {
707 	int res;
708 
709 	lock_sock(sock->sk);
710 	res = __tipc_bind(sock, skaddr, alen);
711 	release_sock(sock->sk);
712 	return res;
713 }
714 
715 static int tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
716 {
717 	struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr;
718 	u32 atype = ua->addrtype;
719 
720 	if (alen) {
721 		if (!tipc_uaddr_valid(ua, alen))
722 			return -EINVAL;
723 		if (atype == TIPC_SOCKET_ADDR)
724 			return -EAFNOSUPPORT;
725 		if (ua->sr.type < TIPC_RESERVED_TYPES) {
726 			pr_warn_once("Can't bind to reserved service type %u\n",
727 				     ua->sr.type);
728 			return -EACCES;
729 		}
730 	}
731 	return tipc_sk_bind(sock, skaddr, alen);
732 }
733 
734 /**
735  * tipc_getname - get port ID of socket or peer socket
736  * @sock: socket structure
737  * @uaddr: area for returned socket address
738  * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
739  *
740  * Return: 0 on success, errno otherwise
741  *
742  * NOTE: This routine doesn't need to take the socket lock since it only
743  *       accesses socket information that is unchanging (or which changes in
744  *       a completely predictable manner).
745  */
746 static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
747 			int peer)
748 {
749 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
750 	struct sock *sk = sock->sk;
751 	struct tipc_sock *tsk = tipc_sk(sk);
752 
753 	memset(addr, 0, sizeof(*addr));
754 	if (peer) {
755 		if ((!tipc_sk_connected(sk)) &&
756 		    ((peer != 2) || (sk->sk_state != TIPC_DISCONNECTING)))
757 			return -ENOTCONN;
758 		addr->addr.id.ref = tsk_peer_port(tsk);
759 		addr->addr.id.node = tsk_peer_node(tsk);
760 	} else {
761 		addr->addr.id.ref = tsk->portid;
762 		addr->addr.id.node = tipc_own_addr(sock_net(sk));
763 	}
764 
765 	addr->addrtype = TIPC_SOCKET_ADDR;
766 	addr->family = AF_TIPC;
767 	addr->scope = 0;
768 	addr->addr.name.domain = 0;
769 
770 	return sizeof(*addr);
771 }
772 
773 /**
774  * tipc_poll - read and possibly block on pollmask
775  * @file: file structure associated with the socket
776  * @sock: socket for which to calculate the poll bits
777  * @wait: ???
778  *
779  * Return: pollmask value
780  *
781  * COMMENTARY:
782  * It appears that the usual socket locking mechanisms are not useful here
783  * since the pollmask info is potentially out-of-date the moment this routine
784  * exits.  TCP and other protocols seem to rely on higher level poll routines
785  * to handle any preventable race conditions, so TIPC will do the same ...
786  *
787  * IMPORTANT: The fact that a read or write operation is indicated does NOT
788  * imply that the operation will succeed, merely that it should be performed
789  * and will not block.
790  */
791 static __poll_t tipc_poll(struct file *file, struct socket *sock,
792 			      poll_table *wait)
793 {
794 	struct sock *sk = sock->sk;
795 	struct tipc_sock *tsk = tipc_sk(sk);
796 	__poll_t revents = 0;
797 
798 	sock_poll_wait(file, sock, wait);
799 	trace_tipc_sk_poll(sk, NULL, TIPC_DUMP_ALL, " ");
800 
801 	if (sk->sk_shutdown & RCV_SHUTDOWN)
802 		revents |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
803 	if (sk->sk_shutdown == SHUTDOWN_MASK)
804 		revents |= EPOLLHUP;
805 
806 	switch (sk->sk_state) {
807 	case TIPC_ESTABLISHED:
808 		if (!tsk->cong_link_cnt && !tsk_conn_cong(tsk))
809 			revents |= EPOLLOUT;
810 		fallthrough;
811 	case TIPC_LISTEN:
812 	case TIPC_CONNECTING:
813 		if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
814 			revents |= EPOLLIN | EPOLLRDNORM;
815 		break;
816 	case TIPC_OPEN:
817 		if (tsk->group_is_open && !tsk->cong_link_cnt)
818 			revents |= EPOLLOUT;
819 		if (!tipc_sk_type_connectionless(sk))
820 			break;
821 		if (skb_queue_empty_lockless(&sk->sk_receive_queue))
822 			break;
823 		revents |= EPOLLIN | EPOLLRDNORM;
824 		break;
825 	case TIPC_DISCONNECTING:
826 		revents = EPOLLIN | EPOLLRDNORM | EPOLLHUP;
827 		break;
828 	}
829 	return revents;
830 }
831 
832 /**
833  * tipc_sendmcast - send multicast message
834  * @sock: socket structure
835  * @ua: destination address struct
836  * @msg: message to send
837  * @dlen: length of data to send
838  * @timeout: timeout to wait for wakeup
839  *
840  * Called from function tipc_sendmsg(), which has done all sanity checks
841  * Return: the number of bytes sent on success, or errno
842  */
843 static int tipc_sendmcast(struct  socket *sock, struct tipc_uaddr *ua,
844 			  struct msghdr *msg, size_t dlen, long timeout)
845 {
846 	struct sock *sk = sock->sk;
847 	struct tipc_sock *tsk = tipc_sk(sk);
848 	struct tipc_msg *hdr = &tsk->phdr;
849 	struct net *net = sock_net(sk);
850 	int mtu = tipc_bcast_get_mtu(net);
851 	struct sk_buff_head pkts;
852 	struct tipc_nlist dsts;
853 	int rc;
854 
855 	if (tsk->group)
856 		return -EACCES;
857 
858 	/* Block or return if any destination link is congested */
859 	rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt);
860 	if (unlikely(rc))
861 		return rc;
862 
863 	/* Lookup destination nodes */
864 	tipc_nlist_init(&dsts, tipc_own_addr(net));
865 	tipc_nametbl_lookup_mcast_nodes(net, ua, &dsts);
866 	if (!dsts.local && !dsts.remote)
867 		return -EHOSTUNREACH;
868 
869 	/* Build message header */
870 	msg_set_type(hdr, TIPC_MCAST_MSG);
871 	msg_set_hdr_sz(hdr, MCAST_H_SIZE);
872 	msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE);
873 	msg_set_destport(hdr, 0);
874 	msg_set_destnode(hdr, 0);
875 	msg_set_nametype(hdr, ua->sr.type);
876 	msg_set_namelower(hdr, ua->sr.lower);
877 	msg_set_nameupper(hdr, ua->sr.upper);
878 
879 	/* Build message as chain of buffers */
880 	__skb_queue_head_init(&pkts);
881 	rc = tipc_msg_build(hdr, msg, 0, dlen, mtu, &pkts);
882 
883 	/* Send message if build was successful */
884 	if (unlikely(rc == dlen)) {
885 		trace_tipc_sk_sendmcast(sk, skb_peek(&pkts),
886 					TIPC_DUMP_SK_SNDQ, " ");
887 		rc = tipc_mcast_xmit(net, &pkts, &tsk->mc_method, &dsts,
888 				     &tsk->cong_link_cnt);
889 	}
890 
891 	tipc_nlist_purge(&dsts);
892 
893 	return rc ? rc : dlen;
894 }
895 
896 /**
897  * tipc_send_group_msg - send a message to a member in the group
898  * @net: network namespace
899  * @tsk: tipc socket
900  * @m: message to send
901  * @mb: group member
902  * @dnode: destination node
903  * @dport: destination port
904  * @dlen: total length of message data
905  */
906 static int tipc_send_group_msg(struct net *net, struct tipc_sock *tsk,
907 			       struct msghdr *m, struct tipc_member *mb,
908 			       u32 dnode, u32 dport, int dlen)
909 {
910 	u16 bc_snd_nxt = tipc_group_bc_snd_nxt(tsk->group);
911 	struct tipc_mc_method *method = &tsk->mc_method;
912 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
913 	struct tipc_msg *hdr = &tsk->phdr;
914 	struct sk_buff_head pkts;
915 	int mtu, rc;
916 
917 	/* Complete message header */
918 	msg_set_type(hdr, TIPC_GRP_UCAST_MSG);
919 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
920 	msg_set_destport(hdr, dport);
921 	msg_set_destnode(hdr, dnode);
922 	msg_set_grp_bc_seqno(hdr, bc_snd_nxt);
923 
924 	/* Build message as chain of buffers */
925 	__skb_queue_head_init(&pkts);
926 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid, false);
927 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
928 	if (unlikely(rc != dlen))
929 		return rc;
930 
931 	/* Send message */
932 	rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
933 	if (unlikely(rc == -ELINKCONG)) {
934 		tipc_dest_push(&tsk->cong_links, dnode, 0);
935 		tsk->cong_link_cnt++;
936 	}
937 
938 	/* Update send window */
939 	tipc_group_update_member(mb, blks);
940 
941 	/* A broadcast sent within next EXPIRE period must follow same path */
942 	method->rcast = true;
943 	method->mandatory = true;
944 	return dlen;
945 }
946 
947 /**
948  * tipc_send_group_unicast - send message to a member in the group
949  * @sock: socket structure
950  * @m: message to send
951  * @dlen: total length of message data
952  * @timeout: timeout to wait for wakeup
953  *
954  * Called from function tipc_sendmsg(), which has done all sanity checks
955  * Return: the number of bytes sent on success, or errno
956  */
957 static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m,
958 				   int dlen, long timeout)
959 {
960 	struct sock *sk = sock->sk;
961 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
962 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
963 	struct tipc_sock *tsk = tipc_sk(sk);
964 	struct net *net = sock_net(sk);
965 	struct tipc_member *mb = NULL;
966 	u32 node, port;
967 	int rc;
968 
969 	node = ua->sk.node;
970 	port = ua->sk.ref;
971 	if (!port && !node)
972 		return -EHOSTUNREACH;
973 
974 	/* Block or return if destination link or member is congested */
975 	rc = tipc_wait_for_cond(sock, &timeout,
976 				!tipc_dest_find(&tsk->cong_links, node, 0) &&
977 				tsk->group &&
978 				!tipc_group_cong(tsk->group, node, port, blks,
979 						 &mb));
980 	if (unlikely(rc))
981 		return rc;
982 
983 	if (unlikely(!mb))
984 		return -EHOSTUNREACH;
985 
986 	rc = tipc_send_group_msg(net, tsk, m, mb, node, port, dlen);
987 
988 	return rc ? rc : dlen;
989 }
990 
991 /**
992  * tipc_send_group_anycast - send message to any member with given identity
993  * @sock: socket structure
994  * @m: message to send
995  * @dlen: total length of message data
996  * @timeout: timeout to wait for wakeup
997  *
998  * Called from function tipc_sendmsg(), which has done all sanity checks
999  * Return: the number of bytes sent on success, or errno
1000  */
1001 static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
1002 				   int dlen, long timeout)
1003 {
1004 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1005 	struct sock *sk = sock->sk;
1006 	struct tipc_sock *tsk = tipc_sk(sk);
1007 	struct list_head *cong_links = &tsk->cong_links;
1008 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
1009 	struct tipc_msg *hdr = &tsk->phdr;
1010 	struct tipc_member *first = NULL;
1011 	struct tipc_member *mbr = NULL;
1012 	struct net *net = sock_net(sk);
1013 	u32 node, port, exclude;
1014 	struct list_head dsts;
1015 	int lookups = 0;
1016 	int dstcnt, rc;
1017 	bool cong;
1018 
1019 	INIT_LIST_HEAD(&dsts);
1020 	ua->sa.type = msg_nametype(hdr);
1021 	ua->scope = msg_lookup_scope(hdr);
1022 
1023 	while (++lookups < 4) {
1024 		exclude = tipc_group_exclude(tsk->group);
1025 
1026 		first = NULL;
1027 
1028 		/* Look for a non-congested destination member, if any */
1029 		while (1) {
1030 			if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt,
1031 						       exclude, false))
1032 				return -EHOSTUNREACH;
1033 			tipc_dest_pop(&dsts, &node, &port);
1034 			cong = tipc_group_cong(tsk->group, node, port, blks,
1035 					       &mbr);
1036 			if (!cong)
1037 				break;
1038 			if (mbr == first)
1039 				break;
1040 			if (!first)
1041 				first = mbr;
1042 		}
1043 
1044 		/* Start over if destination was not in member list */
1045 		if (unlikely(!mbr))
1046 			continue;
1047 
1048 		if (likely(!cong && !tipc_dest_find(cong_links, node, 0)))
1049 			break;
1050 
1051 		/* Block or return if destination link or member is congested */
1052 		rc = tipc_wait_for_cond(sock, &timeout,
1053 					!tipc_dest_find(cong_links, node, 0) &&
1054 					tsk->group &&
1055 					!tipc_group_cong(tsk->group, node, port,
1056 							 blks, &mbr));
1057 		if (unlikely(rc))
1058 			return rc;
1059 
1060 		/* Send, unless destination disappeared while waiting */
1061 		if (likely(mbr))
1062 			break;
1063 	}
1064 
1065 	if (unlikely(lookups >= 4))
1066 		return -EHOSTUNREACH;
1067 
1068 	rc = tipc_send_group_msg(net, tsk, m, mbr, node, port, dlen);
1069 
1070 	return rc ? rc : dlen;
1071 }
1072 
1073 /**
1074  * tipc_send_group_bcast - send message to all members in communication group
1075  * @sock: socket structure
1076  * @m: message to send
1077  * @dlen: total length of message data
1078  * @timeout: timeout to wait for wakeup
1079  *
1080  * Called from function tipc_sendmsg(), which has done all sanity checks
1081  * Return: the number of bytes sent on success, or errno
1082  */
1083 static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
1084 				 int dlen, long timeout)
1085 {
1086 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1087 	struct sock *sk = sock->sk;
1088 	struct net *net = sock_net(sk);
1089 	struct tipc_sock *tsk = tipc_sk(sk);
1090 	struct tipc_nlist *dsts;
1091 	struct tipc_mc_method *method = &tsk->mc_method;
1092 	bool ack = method->mandatory && method->rcast;
1093 	int blks = tsk_blocks(MCAST_H_SIZE + dlen);
1094 	struct tipc_msg *hdr = &tsk->phdr;
1095 	int mtu = tipc_bcast_get_mtu(net);
1096 	struct sk_buff_head pkts;
1097 	int rc = -EHOSTUNREACH;
1098 
1099 	/* Block or return if any destination link or member is congested */
1100 	rc = tipc_wait_for_cond(sock, &timeout,
1101 				!tsk->cong_link_cnt && tsk->group &&
1102 				!tipc_group_bc_cong(tsk->group, blks));
1103 	if (unlikely(rc))
1104 		return rc;
1105 
1106 	dsts = tipc_group_dests(tsk->group);
1107 	if (!dsts->local && !dsts->remote)
1108 		return -EHOSTUNREACH;
1109 
1110 	/* Complete message header */
1111 	if (ua) {
1112 		msg_set_type(hdr, TIPC_GRP_MCAST_MSG);
1113 		msg_set_nameinst(hdr, ua->sa.instance);
1114 	} else {
1115 		msg_set_type(hdr, TIPC_GRP_BCAST_MSG);
1116 		msg_set_nameinst(hdr, 0);
1117 	}
1118 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
1119 	msg_set_destport(hdr, 0);
1120 	msg_set_destnode(hdr, 0);
1121 	msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(tsk->group));
1122 
1123 	/* Avoid getting stuck with repeated forced replicasts */
1124 	msg_set_grp_bc_ack_req(hdr, ack);
1125 
1126 	/* Build message as chain of buffers */
1127 	__skb_queue_head_init(&pkts);
1128 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1129 	if (unlikely(rc != dlen))
1130 		return rc;
1131 
1132 	/* Send message */
1133 	rc = tipc_mcast_xmit(net, &pkts, method, dsts, &tsk->cong_link_cnt);
1134 	if (unlikely(rc))
1135 		return rc;
1136 
1137 	/* Update broadcast sequence number and send windows */
1138 	tipc_group_update_bc_members(tsk->group, blks, ack);
1139 
1140 	/* Broadcast link is now free to choose method for next broadcast */
1141 	method->mandatory = false;
1142 	method->expires = jiffies;
1143 
1144 	return dlen;
1145 }
1146 
1147 /**
1148  * tipc_send_group_mcast - send message to all members with given identity
1149  * @sock: socket structure
1150  * @m: message to send
1151  * @dlen: total length of message data
1152  * @timeout: timeout to wait for wakeup
1153  *
1154  * Called from function tipc_sendmsg(), which has done all sanity checks
1155  * Return: the number of bytes sent on success, or errno
1156  */
1157 static int tipc_send_group_mcast(struct socket *sock, struct msghdr *m,
1158 				 int dlen, long timeout)
1159 {
1160 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1161 	struct sock *sk = sock->sk;
1162 	struct tipc_sock *tsk = tipc_sk(sk);
1163 	struct tipc_group *grp = tsk->group;
1164 	struct tipc_msg *hdr = &tsk->phdr;
1165 	struct net *net = sock_net(sk);
1166 	struct list_head dsts;
1167 	u32 dstcnt, exclude;
1168 
1169 	INIT_LIST_HEAD(&dsts);
1170 	ua->sa.type = msg_nametype(hdr);
1171 	ua->scope = msg_lookup_scope(hdr);
1172 	exclude = tipc_group_exclude(grp);
1173 
1174 	if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt, exclude, true))
1175 		return -EHOSTUNREACH;
1176 
1177 	if (dstcnt == 1) {
1178 		tipc_dest_pop(&dsts, &ua->sk.node, &ua->sk.ref);
1179 		return tipc_send_group_unicast(sock, m, dlen, timeout);
1180 	}
1181 
1182 	tipc_dest_list_purge(&dsts);
1183 	return tipc_send_group_bcast(sock, m, dlen, timeout);
1184 }
1185 
1186 /**
1187  * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets
1188  * @net: the associated network namespace
1189  * @arrvq: queue with arriving messages, to be cloned after destination lookup
1190  * @inputq: queue with cloned messages, delivered to socket after dest lookup
1191  *
1192  * Multi-threaded: parallel calls with reference to same queues may occur
1193  */
1194 void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
1195 		       struct sk_buff_head *inputq)
1196 {
1197 	u32 self = tipc_own_addr(net);
1198 	struct sk_buff *skb, *_skb;
1199 	u32 portid, onode;
1200 	struct sk_buff_head tmpq;
1201 	struct list_head dports;
1202 	struct tipc_msg *hdr;
1203 	struct tipc_uaddr ua;
1204 	int user, mtyp, hlen;
1205 
1206 	__skb_queue_head_init(&tmpq);
1207 	INIT_LIST_HEAD(&dports);
1208 	ua.addrtype = TIPC_SERVICE_RANGE;
1209 
1210 	/* tipc_skb_peek() increments the head skb's reference counter */
1211 	skb = tipc_skb_peek(arrvq, &inputq->lock);
1212 	for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) {
1213 		hdr = buf_msg(skb);
1214 		user = msg_user(hdr);
1215 		mtyp = msg_type(hdr);
1216 		hlen = skb_headroom(skb) + msg_hdr_sz(hdr);
1217 		onode = msg_orignode(hdr);
1218 		ua.sr.type = msg_nametype(hdr);
1219 		ua.sr.lower = msg_namelower(hdr);
1220 		ua.sr.upper = msg_nameupper(hdr);
1221 		if (onode == self)
1222 			ua.scope = TIPC_ANY_SCOPE;
1223 		else
1224 			ua.scope = TIPC_CLUSTER_SCOPE;
1225 
1226 		if (mtyp == TIPC_GRP_UCAST_MSG || user == GROUP_PROTOCOL) {
1227 			spin_lock_bh(&inputq->lock);
1228 			if (skb_peek(arrvq) == skb) {
1229 				__skb_dequeue(arrvq);
1230 				__skb_queue_tail(inputq, skb);
1231 			}
1232 			kfree_skb(skb);
1233 			spin_unlock_bh(&inputq->lock);
1234 			continue;
1235 		}
1236 
1237 		/* Group messages require exact scope match */
1238 		if (msg_in_group(hdr)) {
1239 			ua.sr.lower = 0;
1240 			ua.sr.upper = ~0;
1241 			ua.scope = msg_lookup_scope(hdr);
1242 		}
1243 
1244 		/* Create destination port list: */
1245 		tipc_nametbl_lookup_mcast_sockets(net, &ua, &dports);
1246 
1247 		/* Clone message per destination */
1248 		while (tipc_dest_pop(&dports, NULL, &portid)) {
1249 			_skb = __pskb_copy(skb, hlen, GFP_ATOMIC);
1250 			if (_skb) {
1251 				msg_set_destport(buf_msg(_skb), portid);
1252 				__skb_queue_tail(&tmpq, _skb);
1253 				continue;
1254 			}
1255 			pr_warn("Failed to clone mcast rcv buffer\n");
1256 		}
1257 		/* Append clones to inputq only if skb is still head of arrvq */
1258 		spin_lock_bh(&inputq->lock);
1259 		if (skb_peek(arrvq) == skb) {
1260 			skb_queue_splice_tail_init(&tmpq, inputq);
1261 			/* Decrement the skb's refcnt */
1262 			kfree_skb(__skb_dequeue(arrvq));
1263 		}
1264 		spin_unlock_bh(&inputq->lock);
1265 		__skb_queue_purge(&tmpq);
1266 		kfree_skb(skb);
1267 	}
1268 	tipc_sk_rcv(net, inputq);
1269 }
1270 
1271 /* tipc_sk_push_backlog(): send accumulated buffers in socket write queue
1272  *                         when socket is in Nagle mode
1273  */
1274 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack)
1275 {
1276 	struct sk_buff_head *txq = &tsk->sk.sk_write_queue;
1277 	struct sk_buff *skb = skb_peek_tail(txq);
1278 	struct net *net = sock_net(&tsk->sk);
1279 	u32 dnode = tsk_peer_node(tsk);
1280 	int rc;
1281 
1282 	if (nagle_ack) {
1283 		tsk->pkt_cnt += skb_queue_len(txq);
1284 		if (!tsk->pkt_cnt || tsk->msg_acc / tsk->pkt_cnt < 2) {
1285 			tsk->oneway = 0;
1286 			if (tsk->nagle_start < NAGLE_START_MAX)
1287 				tsk->nagle_start *= 2;
1288 			tsk->expect_ack = false;
1289 			pr_debug("tsk %10u: bad nagle %u -> %u, next start %u!\n",
1290 				 tsk->portid, tsk->msg_acc, tsk->pkt_cnt,
1291 				 tsk->nagle_start);
1292 		} else {
1293 			tsk->nagle_start = NAGLE_START_INIT;
1294 			if (skb) {
1295 				msg_set_ack_required(buf_msg(skb));
1296 				tsk->expect_ack = true;
1297 			} else {
1298 				tsk->expect_ack = false;
1299 			}
1300 		}
1301 		tsk->msg_acc = 0;
1302 		tsk->pkt_cnt = 0;
1303 	}
1304 
1305 	if (!skb || tsk->cong_link_cnt)
1306 		return;
1307 
1308 	/* Do not send SYN again after congestion */
1309 	if (msg_is_syn(buf_msg(skb)))
1310 		return;
1311 
1312 	if (tsk->msg_acc)
1313 		tsk->pkt_cnt += skb_queue_len(txq);
1314 	tsk->snt_unacked += tsk->snd_backlog;
1315 	tsk->snd_backlog = 0;
1316 	rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1317 	if (rc == -ELINKCONG)
1318 		tsk->cong_link_cnt = 1;
1319 }
1320 
1321 /**
1322  * tipc_sk_conn_proto_rcv - receive a connection mng protocol message
1323  * @tsk: receiving socket
1324  * @skb: pointer to message buffer.
1325  * @inputq: buffer list containing the buffers
1326  * @xmitq: output message area
1327  */
1328 static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb,
1329 				   struct sk_buff_head *inputq,
1330 				   struct sk_buff_head *xmitq)
1331 {
1332 	struct tipc_msg *hdr = buf_msg(skb);
1333 	u32 onode = tsk_own_node(tsk);
1334 	struct sock *sk = &tsk->sk;
1335 	int mtyp = msg_type(hdr);
1336 	bool was_cong;
1337 
1338 	/* Ignore if connection cannot be validated: */
1339 	if (!tsk_peer_msg(tsk, hdr)) {
1340 		trace_tipc_sk_drop_msg(sk, skb, TIPC_DUMP_NONE, "@proto_rcv!");
1341 		goto exit;
1342 	}
1343 
1344 	if (unlikely(msg_errcode(hdr))) {
1345 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1346 		tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
1347 				      tsk_peer_port(tsk));
1348 		sk->sk_state_change(sk);
1349 
1350 		/* State change is ignored if socket already awake,
1351 		 * - convert msg to abort msg and add to inqueue
1352 		 */
1353 		msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE);
1354 		msg_set_type(hdr, TIPC_CONN_MSG);
1355 		msg_set_size(hdr, BASIC_H_SIZE);
1356 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1357 		__skb_queue_tail(inputq, skb);
1358 		return;
1359 	}
1360 
1361 	tsk->probe_unacked = false;
1362 
1363 	if (mtyp == CONN_PROBE) {
1364 		msg_set_type(hdr, CONN_PROBE_REPLY);
1365 		if (tipc_msg_reverse(onode, &skb, TIPC_OK))
1366 			__skb_queue_tail(xmitq, skb);
1367 		return;
1368 	} else if (mtyp == CONN_ACK) {
1369 		was_cong = tsk_conn_cong(tsk);
1370 		tipc_sk_push_backlog(tsk, msg_nagle_ack(hdr));
1371 		tsk->snt_unacked -= msg_conn_ack(hdr);
1372 		if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1373 			tsk->snd_win = msg_adv_win(hdr);
1374 		if (was_cong && !tsk_conn_cong(tsk))
1375 			sk->sk_write_space(sk);
1376 	} else if (mtyp != CONN_PROBE_REPLY) {
1377 		pr_warn("Received unknown CONN_PROTO msg\n");
1378 	}
1379 exit:
1380 	kfree_skb(skb);
1381 }
1382 
1383 /**
1384  * tipc_sendmsg - send message in connectionless manner
1385  * @sock: socket structure
1386  * @m: message to send
1387  * @dsz: amount of user data to be sent
1388  *
1389  * Message must have an destination specified explicitly.
1390  * Used for SOCK_RDM and SOCK_DGRAM messages,
1391  * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
1392  * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
1393  *
1394  * Return: the number of bytes sent on success, or errno otherwise
1395  */
1396 static int tipc_sendmsg(struct socket *sock,
1397 			struct msghdr *m, size_t dsz)
1398 {
1399 	struct sock *sk = sock->sk;
1400 	int ret;
1401 
1402 	lock_sock(sk);
1403 	ret = __tipc_sendmsg(sock, m, dsz);
1404 	release_sock(sk);
1405 
1406 	return ret;
1407 }
1408 
1409 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
1410 {
1411 	struct sock *sk = sock->sk;
1412 	struct net *net = sock_net(sk);
1413 	struct tipc_sock *tsk = tipc_sk(sk);
1414 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1415 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1416 	struct list_head *clinks = &tsk->cong_links;
1417 	bool syn = !tipc_sk_type_connectionless(sk);
1418 	struct tipc_group *grp = tsk->group;
1419 	struct tipc_msg *hdr = &tsk->phdr;
1420 	struct tipc_socket_addr skaddr;
1421 	struct sk_buff_head pkts;
1422 	int atype, mtu, rc;
1423 
1424 	if (unlikely(dlen > TIPC_MAX_USER_MSG_SIZE))
1425 		return -EMSGSIZE;
1426 
1427 	if (ua) {
1428 		if (!tipc_uaddr_valid(ua, m->msg_namelen))
1429 			return -EINVAL;
1430 		atype = ua->addrtype;
1431 	}
1432 
1433 	/* If socket belongs to a communication group follow other paths */
1434 	if (grp) {
1435 		if (!ua)
1436 			return tipc_send_group_bcast(sock, m, dlen, timeout);
1437 		if (atype == TIPC_SERVICE_ADDR)
1438 			return tipc_send_group_anycast(sock, m, dlen, timeout);
1439 		if (atype == TIPC_SOCKET_ADDR)
1440 			return tipc_send_group_unicast(sock, m, dlen, timeout);
1441 		if (atype == TIPC_SERVICE_RANGE)
1442 			return tipc_send_group_mcast(sock, m, dlen, timeout);
1443 		return -EINVAL;
1444 	}
1445 
1446 	if (!ua) {
1447 		ua = (struct tipc_uaddr *)&tsk->peer;
1448 		if (!syn && ua->family != AF_TIPC)
1449 			return -EDESTADDRREQ;
1450 		atype = ua->addrtype;
1451 	}
1452 
1453 	if (unlikely(syn)) {
1454 		if (sk->sk_state == TIPC_LISTEN)
1455 			return -EPIPE;
1456 		if (sk->sk_state != TIPC_OPEN)
1457 			return -EISCONN;
1458 		if (tsk->published)
1459 			return -EOPNOTSUPP;
1460 		if (atype == TIPC_SERVICE_ADDR)
1461 			tsk->conn_addrtype = atype;
1462 		msg_set_syn(hdr, 1);
1463 	}
1464 
1465 	memset(&skaddr, 0, sizeof(skaddr));
1466 
1467 	/* Determine destination */
1468 	if (atype == TIPC_SERVICE_RANGE) {
1469 		return tipc_sendmcast(sock, ua, m, dlen, timeout);
1470 	} else if (atype == TIPC_SERVICE_ADDR) {
1471 		skaddr.node = ua->lookup_node;
1472 		ua->scope = tipc_node2scope(skaddr.node);
1473 		if (!tipc_nametbl_lookup_anycast(net, ua, &skaddr))
1474 			return -EHOSTUNREACH;
1475 	} else if (atype == TIPC_SOCKET_ADDR) {
1476 		skaddr = ua->sk;
1477 	} else {
1478 		return -EINVAL;
1479 	}
1480 
1481 	/* Block or return if destination link is congested */
1482 	rc = tipc_wait_for_cond(sock, &timeout,
1483 				!tipc_dest_find(clinks, skaddr.node, 0));
1484 	if (unlikely(rc))
1485 		return rc;
1486 
1487 	/* Finally build message header */
1488 	msg_set_destnode(hdr, skaddr.node);
1489 	msg_set_destport(hdr, skaddr.ref);
1490 	if (atype == TIPC_SERVICE_ADDR) {
1491 		msg_set_type(hdr, TIPC_NAMED_MSG);
1492 		msg_set_hdr_sz(hdr, NAMED_H_SIZE);
1493 		msg_set_nametype(hdr, ua->sa.type);
1494 		msg_set_nameinst(hdr, ua->sa.instance);
1495 		msg_set_lookup_scope(hdr, ua->scope);
1496 	} else { /* TIPC_SOCKET_ADDR */
1497 		msg_set_type(hdr, TIPC_DIRECT_MSG);
1498 		msg_set_lookup_scope(hdr, 0);
1499 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1500 	}
1501 
1502 	/* Add message body */
1503 	__skb_queue_head_init(&pkts);
1504 	mtu = tipc_node_get_mtu(net, skaddr.node, tsk->portid, true);
1505 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1506 	if (unlikely(rc != dlen))
1507 		return rc;
1508 	if (unlikely(syn && !tipc_msg_skb_clone(&pkts, &sk->sk_write_queue))) {
1509 		__skb_queue_purge(&pkts);
1510 		return -ENOMEM;
1511 	}
1512 
1513 	/* Send message */
1514 	trace_tipc_sk_sendmsg(sk, skb_peek(&pkts), TIPC_DUMP_SK_SNDQ, " ");
1515 	rc = tipc_node_xmit(net, &pkts, skaddr.node, tsk->portid);
1516 	if (unlikely(rc == -ELINKCONG)) {
1517 		tipc_dest_push(clinks, skaddr.node, 0);
1518 		tsk->cong_link_cnt++;
1519 		rc = 0;
1520 	}
1521 
1522 	if (unlikely(syn && !rc)) {
1523 		tipc_set_sk_state(sk, TIPC_CONNECTING);
1524 		if (dlen && timeout) {
1525 			timeout = msecs_to_jiffies(timeout);
1526 			tipc_wait_for_connect(sock, &timeout);
1527 		}
1528 	}
1529 
1530 	return rc ? rc : dlen;
1531 }
1532 
1533 /**
1534  * tipc_sendstream - send stream-oriented data
1535  * @sock: socket structure
1536  * @m: data to send
1537  * @dsz: total length of data to be transmitted
1538  *
1539  * Used for SOCK_STREAM data.
1540  *
1541  * Return: the number of bytes sent on success (or partial success),
1542  * or errno if no data sent
1543  */
1544 static int tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz)
1545 {
1546 	struct sock *sk = sock->sk;
1547 	int ret;
1548 
1549 	lock_sock(sk);
1550 	ret = __tipc_sendstream(sock, m, dsz);
1551 	release_sock(sk);
1552 
1553 	return ret;
1554 }
1555 
1556 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dlen)
1557 {
1558 	struct sock *sk = sock->sk;
1559 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1560 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1561 	struct sk_buff_head *txq = &sk->sk_write_queue;
1562 	struct tipc_sock *tsk = tipc_sk(sk);
1563 	struct tipc_msg *hdr = &tsk->phdr;
1564 	struct net *net = sock_net(sk);
1565 	struct sk_buff *skb;
1566 	u32 dnode = tsk_peer_node(tsk);
1567 	int maxnagle = tsk->maxnagle;
1568 	int maxpkt = tsk->max_pkt;
1569 	int send, sent = 0;
1570 	int blocks, rc = 0;
1571 
1572 	if (unlikely(dlen > INT_MAX))
1573 		return -EMSGSIZE;
1574 
1575 	/* Handle implicit connection setup */
1576 	if (unlikely(dest && sk->sk_state == TIPC_OPEN)) {
1577 		rc = __tipc_sendmsg(sock, m, dlen);
1578 		if (dlen && dlen == rc) {
1579 			tsk->peer_caps = tipc_node_get_capabilities(net, dnode);
1580 			tsk->snt_unacked = tsk_inc(tsk, dlen + msg_hdr_sz(hdr));
1581 		}
1582 		return rc;
1583 	}
1584 
1585 	do {
1586 		rc = tipc_wait_for_cond(sock, &timeout,
1587 					(!tsk->cong_link_cnt &&
1588 					 !tsk_conn_cong(tsk) &&
1589 					 tipc_sk_connected(sk)));
1590 		if (unlikely(rc))
1591 			break;
1592 		send = min_t(size_t, dlen - sent, TIPC_MAX_USER_MSG_SIZE);
1593 		blocks = tsk->snd_backlog;
1594 		if (tsk->oneway++ >= tsk->nagle_start && maxnagle &&
1595 		    send <= maxnagle) {
1596 			rc = tipc_msg_append(hdr, m, send, maxnagle, txq);
1597 			if (unlikely(rc < 0))
1598 				break;
1599 			blocks += rc;
1600 			tsk->msg_acc++;
1601 			if (blocks <= 64 && tsk->expect_ack) {
1602 				tsk->snd_backlog = blocks;
1603 				sent += send;
1604 				break;
1605 			} else if (blocks > 64) {
1606 				tsk->pkt_cnt += skb_queue_len(txq);
1607 			} else {
1608 				skb = skb_peek_tail(txq);
1609 				if (skb) {
1610 					msg_set_ack_required(buf_msg(skb));
1611 					tsk->expect_ack = true;
1612 				} else {
1613 					tsk->expect_ack = false;
1614 				}
1615 				tsk->msg_acc = 0;
1616 				tsk->pkt_cnt = 0;
1617 			}
1618 		} else {
1619 			rc = tipc_msg_build(hdr, m, sent, send, maxpkt, txq);
1620 			if (unlikely(rc != send))
1621 				break;
1622 			blocks += tsk_inc(tsk, send + MIN_H_SIZE);
1623 		}
1624 		trace_tipc_sk_sendstream(sk, skb_peek(txq),
1625 					 TIPC_DUMP_SK_SNDQ, " ");
1626 		rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1627 		if (unlikely(rc == -ELINKCONG)) {
1628 			tsk->cong_link_cnt = 1;
1629 			rc = 0;
1630 		}
1631 		if (likely(!rc)) {
1632 			tsk->snt_unacked += blocks;
1633 			tsk->snd_backlog = 0;
1634 			sent += send;
1635 		}
1636 	} while (sent < dlen && !rc);
1637 
1638 	return sent ? sent : rc;
1639 }
1640 
1641 /**
1642  * tipc_send_packet - send a connection-oriented message
1643  * @sock: socket structure
1644  * @m: message to send
1645  * @dsz: length of data to be transmitted
1646  *
1647  * Used for SOCK_SEQPACKET messages.
1648  *
1649  * Return: the number of bytes sent on success, or errno otherwise
1650  */
1651 static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz)
1652 {
1653 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
1654 		return -EMSGSIZE;
1655 
1656 	return tipc_sendstream(sock, m, dsz);
1657 }
1658 
1659 /* tipc_sk_finish_conn - complete the setup of a connection
1660  */
1661 static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port,
1662 				u32 peer_node)
1663 {
1664 	struct sock *sk = &tsk->sk;
1665 	struct net *net = sock_net(sk);
1666 	struct tipc_msg *msg = &tsk->phdr;
1667 
1668 	msg_set_syn(msg, 0);
1669 	msg_set_destnode(msg, peer_node);
1670 	msg_set_destport(msg, peer_port);
1671 	msg_set_type(msg, TIPC_CONN_MSG);
1672 	msg_set_lookup_scope(msg, 0);
1673 	msg_set_hdr_sz(msg, SHORT_H_SIZE);
1674 
1675 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
1676 	tipc_set_sk_state(sk, TIPC_ESTABLISHED);
1677 	tipc_node_add_conn(net, peer_node, tsk->portid, peer_port);
1678 	tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid, true);
1679 	tsk->peer_caps = tipc_node_get_capabilities(net, peer_node);
1680 	tsk_set_nagle(tsk);
1681 	__skb_queue_purge(&sk->sk_write_queue);
1682 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1683 		return;
1684 
1685 	/* Fall back to message based flow control */
1686 	tsk->rcv_win = FLOWCTL_MSG_WIN;
1687 	tsk->snd_win = FLOWCTL_MSG_WIN;
1688 }
1689 
1690 /**
1691  * tipc_sk_set_orig_addr - capture sender's address for received message
1692  * @m: descriptor for message info
1693  * @skb: received message
1694  *
1695  * Note: Address is not captured if not requested by receiver.
1696  */
1697 static void tipc_sk_set_orig_addr(struct msghdr *m, struct sk_buff *skb)
1698 {
1699 	DECLARE_SOCKADDR(struct sockaddr_pair *, srcaddr, m->msg_name);
1700 	struct tipc_msg *hdr = buf_msg(skb);
1701 
1702 	if (!srcaddr)
1703 		return;
1704 
1705 	srcaddr->sock.family = AF_TIPC;
1706 	srcaddr->sock.addrtype = TIPC_SOCKET_ADDR;
1707 	srcaddr->sock.scope = 0;
1708 	srcaddr->sock.addr.id.ref = msg_origport(hdr);
1709 	srcaddr->sock.addr.id.node = msg_orignode(hdr);
1710 	srcaddr->sock.addr.name.domain = 0;
1711 	m->msg_namelen = sizeof(struct sockaddr_tipc);
1712 
1713 	if (!msg_in_group(hdr))
1714 		return;
1715 
1716 	/* Group message users may also want to know sending member's id */
1717 	srcaddr->member.family = AF_TIPC;
1718 	srcaddr->member.addrtype = TIPC_SERVICE_ADDR;
1719 	srcaddr->member.scope = 0;
1720 	srcaddr->member.addr.name.name.type = msg_nametype(hdr);
1721 	srcaddr->member.addr.name.name.instance = TIPC_SKB_CB(skb)->orig_member;
1722 	srcaddr->member.addr.name.domain = 0;
1723 	m->msg_namelen = sizeof(*srcaddr);
1724 }
1725 
1726 /**
1727  * tipc_sk_anc_data_recv - optionally capture ancillary data for received message
1728  * @m: descriptor for message info
1729  * @skb: received message buffer
1730  * @tsk: TIPC port associated with message
1731  *
1732  * Note: Ancillary data is not captured if not requested by receiver.
1733  *
1734  * Return: 0 if successful, otherwise errno
1735  */
1736 static int tipc_sk_anc_data_recv(struct msghdr *m, struct sk_buff *skb,
1737 				 struct tipc_sock *tsk)
1738 {
1739 	struct tipc_msg *hdr;
1740 	u32 data[3] = {0,};
1741 	bool has_addr;
1742 	int dlen, rc;
1743 
1744 	if (likely(m->msg_controllen == 0))
1745 		return 0;
1746 
1747 	hdr = buf_msg(skb);
1748 	dlen = msg_data_sz(hdr);
1749 
1750 	/* Capture errored message object, if any */
1751 	if (msg_errcode(hdr)) {
1752 		if (skb_linearize(skb))
1753 			return -ENOMEM;
1754 		hdr = buf_msg(skb);
1755 		data[0] = msg_errcode(hdr);
1756 		data[1] = dlen;
1757 		rc = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, data);
1758 		if (rc || !dlen)
1759 			return rc;
1760 		rc = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, dlen, msg_data(hdr));
1761 		if (rc)
1762 			return rc;
1763 	}
1764 
1765 	/* Capture TIPC_SERVICE_ADDR/RANGE destination address, if any */
1766 	switch (msg_type(hdr)) {
1767 	case TIPC_NAMED_MSG:
1768 		has_addr = true;
1769 		data[0] = msg_nametype(hdr);
1770 		data[1] = msg_namelower(hdr);
1771 		data[2] = data[1];
1772 		break;
1773 	case TIPC_MCAST_MSG:
1774 		has_addr = true;
1775 		data[0] = msg_nametype(hdr);
1776 		data[1] = msg_namelower(hdr);
1777 		data[2] = msg_nameupper(hdr);
1778 		break;
1779 	case TIPC_CONN_MSG:
1780 		has_addr = !!tsk->conn_addrtype;
1781 		data[0] = msg_nametype(&tsk->phdr);
1782 		data[1] = msg_nameinst(&tsk->phdr);
1783 		data[2] = data[1];
1784 		break;
1785 	default:
1786 		has_addr = false;
1787 	}
1788 	if (!has_addr)
1789 		return 0;
1790 	return put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, data);
1791 }
1792 
1793 static struct sk_buff *tipc_sk_build_ack(struct tipc_sock *tsk)
1794 {
1795 	struct sock *sk = &tsk->sk;
1796 	struct sk_buff *skb = NULL;
1797 	struct tipc_msg *msg;
1798 	u32 peer_port = tsk_peer_port(tsk);
1799 	u32 dnode = tsk_peer_node(tsk);
1800 
1801 	if (!tipc_sk_connected(sk))
1802 		return NULL;
1803 	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
1804 			      dnode, tsk_own_node(tsk), peer_port,
1805 			      tsk->portid, TIPC_OK);
1806 	if (!skb)
1807 		return NULL;
1808 	msg = buf_msg(skb);
1809 	msg_set_conn_ack(msg, tsk->rcv_unacked);
1810 	tsk->rcv_unacked = 0;
1811 
1812 	/* Adjust to and advertize the correct window limit */
1813 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) {
1814 		tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf);
1815 		msg_set_adv_win(msg, tsk->rcv_win);
1816 	}
1817 	return skb;
1818 }
1819 
1820 static void tipc_sk_send_ack(struct tipc_sock *tsk)
1821 {
1822 	struct sk_buff *skb;
1823 
1824 	skb = tipc_sk_build_ack(tsk);
1825 	if (!skb)
1826 		return;
1827 
1828 	tipc_node_xmit_skb(sock_net(&tsk->sk), skb, tsk_peer_node(tsk),
1829 			   msg_link_selector(buf_msg(skb)));
1830 }
1831 
1832 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
1833 {
1834 	struct sock *sk = sock->sk;
1835 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1836 	long timeo = *timeop;
1837 	int err = sock_error(sk);
1838 
1839 	if (err)
1840 		return err;
1841 
1842 	for (;;) {
1843 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1844 			if (sk->sk_shutdown & RCV_SHUTDOWN) {
1845 				err = -ENOTCONN;
1846 				break;
1847 			}
1848 			add_wait_queue(sk_sleep(sk), &wait);
1849 			release_sock(sk);
1850 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
1851 			sched_annotate_sleep();
1852 			lock_sock(sk);
1853 			remove_wait_queue(sk_sleep(sk), &wait);
1854 		}
1855 		err = 0;
1856 		if (!skb_queue_empty(&sk->sk_receive_queue))
1857 			break;
1858 		err = -EAGAIN;
1859 		if (!timeo)
1860 			break;
1861 		err = sock_intr_errno(timeo);
1862 		if (signal_pending(current))
1863 			break;
1864 
1865 		err = sock_error(sk);
1866 		if (err)
1867 			break;
1868 	}
1869 	*timeop = timeo;
1870 	return err;
1871 }
1872 
1873 /**
1874  * tipc_recvmsg - receive packet-oriented message
1875  * @sock: network socket
1876  * @m: descriptor for message info
1877  * @buflen: length of user buffer area
1878  * @flags: receive flags
1879  *
1880  * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1881  * If the complete message doesn't fit in user area, truncate it.
1882  *
1883  * Return: size of returned message data, errno otherwise
1884  */
1885 static int tipc_recvmsg(struct socket *sock, struct msghdr *m,
1886 			size_t buflen,	int flags)
1887 {
1888 	struct sock *sk = sock->sk;
1889 	bool connected = !tipc_sk_type_connectionless(sk);
1890 	struct tipc_sock *tsk = tipc_sk(sk);
1891 	int rc, err, hlen, dlen, copy;
1892 	struct tipc_skb_cb *skb_cb;
1893 	struct sk_buff_head xmitq;
1894 	struct tipc_msg *hdr;
1895 	struct sk_buff *skb;
1896 	bool grp_evt;
1897 	long timeout;
1898 
1899 	/* Catch invalid receive requests */
1900 	if (unlikely(!buflen))
1901 		return -EINVAL;
1902 
1903 	lock_sock(sk);
1904 	if (unlikely(connected && sk->sk_state == TIPC_OPEN)) {
1905 		rc = -ENOTCONN;
1906 		goto exit;
1907 	}
1908 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1909 
1910 	/* Step rcv queue to first msg with data or error; wait if necessary */
1911 	do {
1912 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
1913 		if (unlikely(rc))
1914 			goto exit;
1915 		skb = skb_peek(&sk->sk_receive_queue);
1916 		skb_cb = TIPC_SKB_CB(skb);
1917 		hdr = buf_msg(skb);
1918 		dlen = msg_data_sz(hdr);
1919 		hlen = msg_hdr_sz(hdr);
1920 		err = msg_errcode(hdr);
1921 		grp_evt = msg_is_grp_evt(hdr);
1922 		if (likely(dlen || err))
1923 			break;
1924 		tsk_advance_rx_queue(sk);
1925 	} while (1);
1926 
1927 	/* Collect msg meta data, including error code and rejected data */
1928 	tipc_sk_set_orig_addr(m, skb);
1929 	rc = tipc_sk_anc_data_recv(m, skb, tsk);
1930 	if (unlikely(rc))
1931 		goto exit;
1932 	hdr = buf_msg(skb);
1933 
1934 	/* Capture data if non-error msg, otherwise just set return value */
1935 	if (likely(!err)) {
1936 		int offset = skb_cb->bytes_read;
1937 
1938 		copy = min_t(int, dlen - offset, buflen);
1939 		rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
1940 		if (unlikely(rc))
1941 			goto exit;
1942 		if (unlikely(offset + copy < dlen)) {
1943 			if (flags & MSG_EOR) {
1944 				if (!(flags & MSG_PEEK))
1945 					skb_cb->bytes_read = offset + copy;
1946 			} else {
1947 				m->msg_flags |= MSG_TRUNC;
1948 				skb_cb->bytes_read = 0;
1949 			}
1950 		} else {
1951 			if (flags & MSG_EOR)
1952 				m->msg_flags |= MSG_EOR;
1953 			skb_cb->bytes_read = 0;
1954 		}
1955 	} else {
1956 		copy = 0;
1957 		rc = 0;
1958 		if (err != TIPC_CONN_SHUTDOWN && connected && !m->msg_control) {
1959 			rc = -ECONNRESET;
1960 			goto exit;
1961 		}
1962 	}
1963 
1964 	/* Mark message as group event if applicable */
1965 	if (unlikely(grp_evt)) {
1966 		if (msg_grp_evt(hdr) == TIPC_WITHDRAWN)
1967 			m->msg_flags |= MSG_EOR;
1968 		m->msg_flags |= MSG_OOB;
1969 		copy = 0;
1970 	}
1971 
1972 	/* Caption of data or error code/rejected data was successful */
1973 	if (unlikely(flags & MSG_PEEK))
1974 		goto exit;
1975 
1976 	/* Send group flow control advertisement when applicable */
1977 	if (tsk->group && msg_in_group(hdr) && !grp_evt) {
1978 		__skb_queue_head_init(&xmitq);
1979 		tipc_group_update_rcv_win(tsk->group, tsk_blocks(hlen + dlen),
1980 					  msg_orignode(hdr), msg_origport(hdr),
1981 					  &xmitq);
1982 		tipc_node_distr_xmit(sock_net(sk), &xmitq);
1983 	}
1984 
1985 	if (skb_cb->bytes_read)
1986 		goto exit;
1987 
1988 	tsk_advance_rx_queue(sk);
1989 
1990 	if (likely(!connected))
1991 		goto exit;
1992 
1993 	/* Send connection flow control advertisement when applicable */
1994 	tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
1995 	if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
1996 		tipc_sk_send_ack(tsk);
1997 exit:
1998 	release_sock(sk);
1999 	return rc ? rc : copy;
2000 }
2001 
2002 /**
2003  * tipc_recvstream - receive stream-oriented data
2004  * @sock: network socket
2005  * @m: descriptor for message info
2006  * @buflen: total size of user buffer area
2007  * @flags: receive flags
2008  *
2009  * Used for SOCK_STREAM messages only.  If not enough data is available
2010  * will optionally wait for more; never truncates data.
2011  *
2012  * Return: size of returned message data, errno otherwise
2013  */
2014 static int tipc_recvstream(struct socket *sock, struct msghdr *m,
2015 			   size_t buflen, int flags)
2016 {
2017 	struct sock *sk = sock->sk;
2018 	struct tipc_sock *tsk = tipc_sk(sk);
2019 	struct sk_buff *skb;
2020 	struct tipc_msg *hdr;
2021 	struct tipc_skb_cb *skb_cb;
2022 	bool peek = flags & MSG_PEEK;
2023 	int offset, required, copy, copied = 0;
2024 	int hlen, dlen, err, rc;
2025 	long timeout;
2026 
2027 	/* Catch invalid receive attempts */
2028 	if (unlikely(!buflen))
2029 		return -EINVAL;
2030 
2031 	lock_sock(sk);
2032 
2033 	if (unlikely(sk->sk_state == TIPC_OPEN)) {
2034 		rc = -ENOTCONN;
2035 		goto exit;
2036 	}
2037 	required = sock_rcvlowat(sk, flags & MSG_WAITALL, buflen);
2038 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
2039 
2040 	do {
2041 		/* Look at first msg in receive queue; wait if necessary */
2042 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
2043 		if (unlikely(rc))
2044 			break;
2045 		skb = skb_peek(&sk->sk_receive_queue);
2046 		skb_cb = TIPC_SKB_CB(skb);
2047 		hdr = buf_msg(skb);
2048 		dlen = msg_data_sz(hdr);
2049 		hlen = msg_hdr_sz(hdr);
2050 		err = msg_errcode(hdr);
2051 
2052 		/* Discard any empty non-errored (SYN-) message */
2053 		if (unlikely(!dlen && !err)) {
2054 			tsk_advance_rx_queue(sk);
2055 			continue;
2056 		}
2057 
2058 		/* Collect msg meta data, incl. error code and rejected data */
2059 		if (!copied) {
2060 			tipc_sk_set_orig_addr(m, skb);
2061 			rc = tipc_sk_anc_data_recv(m, skb, tsk);
2062 			if (rc)
2063 				break;
2064 			hdr = buf_msg(skb);
2065 		}
2066 
2067 		/* Copy data if msg ok, otherwise return error/partial data */
2068 		if (likely(!err)) {
2069 			offset = skb_cb->bytes_read;
2070 			copy = min_t(int, dlen - offset, buflen - copied);
2071 			rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
2072 			if (unlikely(rc))
2073 				break;
2074 			copied += copy;
2075 			offset += copy;
2076 			if (unlikely(offset < dlen)) {
2077 				if (!peek)
2078 					skb_cb->bytes_read = offset;
2079 				break;
2080 			}
2081 		} else {
2082 			rc = 0;
2083 			if ((err != TIPC_CONN_SHUTDOWN) && !m->msg_control)
2084 				rc = -ECONNRESET;
2085 			if (copied || rc)
2086 				break;
2087 		}
2088 
2089 		if (unlikely(peek))
2090 			break;
2091 
2092 		tsk_advance_rx_queue(sk);
2093 
2094 		/* Send connection flow control advertisement when applicable */
2095 		tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
2096 		if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
2097 			tipc_sk_send_ack(tsk);
2098 
2099 		/* Exit if all requested data or FIN/error received */
2100 		if (copied == buflen || err)
2101 			break;
2102 
2103 	} while (!skb_queue_empty(&sk->sk_receive_queue) || copied < required);
2104 exit:
2105 	release_sock(sk);
2106 	return copied ? copied : rc;
2107 }
2108 
2109 /**
2110  * tipc_write_space - wake up thread if port congestion is released
2111  * @sk: socket
2112  */
2113 static void tipc_write_space(struct sock *sk)
2114 {
2115 	struct socket_wq *wq;
2116 
2117 	rcu_read_lock();
2118 	wq = rcu_dereference(sk->sk_wq);
2119 	if (skwq_has_sleeper(wq))
2120 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2121 						EPOLLWRNORM | EPOLLWRBAND);
2122 	rcu_read_unlock();
2123 }
2124 
2125 /**
2126  * tipc_data_ready - wake up threads to indicate messages have been received
2127  * @sk: socket
2128  */
2129 static void tipc_data_ready(struct sock *sk)
2130 {
2131 	struct socket_wq *wq;
2132 
2133 	trace_sk_data_ready(sk);
2134 
2135 	rcu_read_lock();
2136 	wq = rcu_dereference(sk->sk_wq);
2137 	if (skwq_has_sleeper(wq))
2138 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
2139 						EPOLLRDNORM | EPOLLRDBAND);
2140 	rcu_read_unlock();
2141 }
2142 
2143 static void tipc_sock_destruct(struct sock *sk)
2144 {
2145 	__skb_queue_purge(&sk->sk_receive_queue);
2146 }
2147 
2148 static void tipc_sk_proto_rcv(struct sock *sk,
2149 			      struct sk_buff_head *inputq,
2150 			      struct sk_buff_head *xmitq)
2151 {
2152 	struct sk_buff *skb = __skb_dequeue(inputq);
2153 	struct tipc_sock *tsk = tipc_sk(sk);
2154 	struct tipc_msg *hdr = buf_msg(skb);
2155 	struct tipc_group *grp = tsk->group;
2156 	bool wakeup = false;
2157 
2158 	switch (msg_user(hdr)) {
2159 	case CONN_MANAGER:
2160 		tipc_sk_conn_proto_rcv(tsk, skb, inputq, xmitq);
2161 		return;
2162 	case SOCK_WAKEUP:
2163 		tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0);
2164 		/* coupled with smp_rmb() in tipc_wait_for_cond() */
2165 		smp_wmb();
2166 		tsk->cong_link_cnt--;
2167 		wakeup = true;
2168 		tipc_sk_push_backlog(tsk, false);
2169 		break;
2170 	case GROUP_PROTOCOL:
2171 		tipc_group_proto_rcv(grp, &wakeup, hdr, inputq, xmitq);
2172 		break;
2173 	case TOP_SRV:
2174 		tipc_group_member_evt(tsk->group, &wakeup, &sk->sk_rcvbuf,
2175 				      hdr, inputq, xmitq);
2176 		break;
2177 	default:
2178 		break;
2179 	}
2180 
2181 	if (wakeup)
2182 		sk->sk_write_space(sk);
2183 
2184 	kfree_skb(skb);
2185 }
2186 
2187 /**
2188  * tipc_sk_filter_connect - check incoming message for a connection-based socket
2189  * @tsk: TIPC socket
2190  * @skb: pointer to message buffer.
2191  * @xmitq: for Nagle ACK if any
2192  * Return: true if message should be added to receive queue, false otherwise
2193  */
2194 static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb,
2195 				   struct sk_buff_head *xmitq)
2196 {
2197 	struct sock *sk = &tsk->sk;
2198 	struct net *net = sock_net(sk);
2199 	struct tipc_msg *hdr = buf_msg(skb);
2200 	bool con_msg = msg_connected(hdr);
2201 	u32 pport = tsk_peer_port(tsk);
2202 	u32 pnode = tsk_peer_node(tsk);
2203 	u32 oport = msg_origport(hdr);
2204 	u32 onode = msg_orignode(hdr);
2205 	int err = msg_errcode(hdr);
2206 	unsigned long delay;
2207 
2208 	if (unlikely(msg_mcast(hdr)))
2209 		return false;
2210 	tsk->oneway = 0;
2211 
2212 	switch (sk->sk_state) {
2213 	case TIPC_CONNECTING:
2214 		/* Setup ACK */
2215 		if (likely(con_msg)) {
2216 			if (err)
2217 				break;
2218 			tipc_sk_finish_conn(tsk, oport, onode);
2219 			msg_set_importance(&tsk->phdr, msg_importance(hdr));
2220 			/* ACK+ message with data is added to receive queue */
2221 			if (msg_data_sz(hdr))
2222 				return true;
2223 			/* Empty ACK-, - wake up sleeping connect() and drop */
2224 			sk->sk_state_change(sk);
2225 			msg_set_dest_droppable(hdr, 1);
2226 			return false;
2227 		}
2228 		/* Ignore connectionless message if not from listening socket */
2229 		if (oport != pport || onode != pnode)
2230 			return false;
2231 
2232 		/* Rejected SYN */
2233 		if (err != TIPC_ERR_OVERLOAD)
2234 			break;
2235 
2236 		/* Prepare for new setup attempt if we have a SYN clone */
2237 		if (skb_queue_empty(&sk->sk_write_queue))
2238 			break;
2239 		get_random_bytes(&delay, 2);
2240 		delay %= (tsk->conn_timeout / 4);
2241 		delay = msecs_to_jiffies(delay + 100);
2242 		sk_reset_timer(sk, &sk->sk_timer, jiffies + delay);
2243 		return false;
2244 	case TIPC_OPEN:
2245 	case TIPC_DISCONNECTING:
2246 		return false;
2247 	case TIPC_LISTEN:
2248 		/* Accept only SYN message */
2249 		if (!msg_is_syn(hdr) &&
2250 		    tipc_node_get_capabilities(net, onode) & TIPC_SYN_BIT)
2251 			return false;
2252 		if (!con_msg && !err)
2253 			return true;
2254 		return false;
2255 	case TIPC_ESTABLISHED:
2256 		if (!skb_queue_empty(&sk->sk_write_queue))
2257 			tipc_sk_push_backlog(tsk, false);
2258 		/* Accept only connection-based messages sent by peer */
2259 		if (likely(con_msg && !err && pport == oport &&
2260 			   pnode == onode)) {
2261 			if (msg_ack_required(hdr)) {
2262 				struct sk_buff *skb;
2263 
2264 				skb = tipc_sk_build_ack(tsk);
2265 				if (skb) {
2266 					msg_set_nagle_ack(buf_msg(skb));
2267 					__skb_queue_tail(xmitq, skb);
2268 				}
2269 			}
2270 			return true;
2271 		}
2272 		if (!tsk_peer_msg(tsk, hdr))
2273 			return false;
2274 		if (!err)
2275 			return true;
2276 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2277 		tipc_node_remove_conn(net, pnode, tsk->portid);
2278 		sk->sk_state_change(sk);
2279 		return true;
2280 	default:
2281 		pr_err("Unknown sk_state %u\n", sk->sk_state);
2282 	}
2283 	/* Abort connection setup attempt */
2284 	tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2285 	sk->sk_err = ECONNREFUSED;
2286 	sk->sk_state_change(sk);
2287 	return true;
2288 }
2289 
2290 /**
2291  * rcvbuf_limit - get proper overload limit of socket receive queue
2292  * @sk: socket
2293  * @skb: message
2294  *
2295  * For connection oriented messages, irrespective of importance,
2296  * default queue limit is 2 MB.
2297  *
2298  * For connectionless messages, queue limits are based on message
2299  * importance as follows:
2300  *
2301  * TIPC_LOW_IMPORTANCE       (2 MB)
2302  * TIPC_MEDIUM_IMPORTANCE    (4 MB)
2303  * TIPC_HIGH_IMPORTANCE      (8 MB)
2304  * TIPC_CRITICAL_IMPORTANCE  (16 MB)
2305  *
2306  * Return: overload limit according to corresponding message importance
2307  */
2308 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb)
2309 {
2310 	struct tipc_sock *tsk = tipc_sk(sk);
2311 	struct tipc_msg *hdr = buf_msg(skb);
2312 
2313 	if (unlikely(msg_in_group(hdr)))
2314 		return READ_ONCE(sk->sk_rcvbuf);
2315 
2316 	if (unlikely(!msg_connected(hdr)))
2317 		return READ_ONCE(sk->sk_rcvbuf) << msg_importance(hdr);
2318 
2319 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
2320 		return READ_ONCE(sk->sk_rcvbuf);
2321 
2322 	return FLOWCTL_MSG_LIM;
2323 }
2324 
2325 /**
2326  * tipc_sk_filter_rcv - validate incoming message
2327  * @sk: socket
2328  * @skb: pointer to message.
2329  * @xmitq: output message area (FIXME)
2330  *
2331  * Enqueues message on receive queue if acceptable; optionally handles
2332  * disconnect indication for a connected socket.
2333  *
2334  * Called with socket lock already taken
2335  */
2336 static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb,
2337 			       struct sk_buff_head *xmitq)
2338 {
2339 	bool sk_conn = !tipc_sk_type_connectionless(sk);
2340 	struct tipc_sock *tsk = tipc_sk(sk);
2341 	struct tipc_group *grp = tsk->group;
2342 	struct tipc_msg *hdr = buf_msg(skb);
2343 	struct net *net = sock_net(sk);
2344 	struct sk_buff_head inputq;
2345 	int mtyp = msg_type(hdr);
2346 	int limit, err = TIPC_OK;
2347 
2348 	trace_tipc_sk_filter_rcv(sk, skb, TIPC_DUMP_ALL, " ");
2349 	TIPC_SKB_CB(skb)->bytes_read = 0;
2350 	__skb_queue_head_init(&inputq);
2351 	__skb_queue_tail(&inputq, skb);
2352 
2353 	if (unlikely(!msg_isdata(hdr)))
2354 		tipc_sk_proto_rcv(sk, &inputq, xmitq);
2355 
2356 	if (unlikely(grp))
2357 		tipc_group_filter_msg(grp, &inputq, xmitq);
2358 
2359 	if (unlikely(!grp) && mtyp == TIPC_MCAST_MSG)
2360 		tipc_mcast_filter_msg(net, &tsk->mc_method.deferredq, &inputq);
2361 
2362 	/* Validate and add to receive buffer if there is space */
2363 	while ((skb = __skb_dequeue(&inputq))) {
2364 		hdr = buf_msg(skb);
2365 		limit = rcvbuf_limit(sk, skb);
2366 		if ((sk_conn && !tipc_sk_filter_connect(tsk, skb, xmitq)) ||
2367 		    (!sk_conn && msg_connected(hdr)) ||
2368 		    (!grp && msg_in_group(hdr)))
2369 			err = TIPC_ERR_NO_PORT;
2370 		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit) {
2371 			trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL,
2372 					   "err_overload2!");
2373 			atomic_inc(&sk->sk_drops);
2374 			err = TIPC_ERR_OVERLOAD;
2375 		}
2376 
2377 		if (unlikely(err)) {
2378 			if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) {
2379 				trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE,
2380 						      "@filter_rcv!");
2381 				__skb_queue_tail(xmitq, skb);
2382 			}
2383 			err = TIPC_OK;
2384 			continue;
2385 		}
2386 		__skb_queue_tail(&sk->sk_receive_queue, skb);
2387 		skb_set_owner_r(skb, sk);
2388 		trace_tipc_sk_overlimit2(sk, skb, TIPC_DUMP_ALL,
2389 					 "rcvq >90% allocated!");
2390 		sk->sk_data_ready(sk);
2391 	}
2392 }
2393 
2394 /**
2395  * tipc_sk_backlog_rcv - handle incoming message from backlog queue
2396  * @sk: socket
2397  * @skb: message
2398  *
2399  * Caller must hold socket lock
2400  */
2401 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
2402 {
2403 	unsigned int before = sk_rmem_alloc_get(sk);
2404 	struct sk_buff_head xmitq;
2405 	unsigned int added;
2406 
2407 	__skb_queue_head_init(&xmitq);
2408 
2409 	tipc_sk_filter_rcv(sk, skb, &xmitq);
2410 	added = sk_rmem_alloc_get(sk) - before;
2411 	atomic_add(added, &tipc_sk(sk)->dupl_rcvcnt);
2412 
2413 	/* Send pending response/rejected messages, if any */
2414 	tipc_node_distr_xmit(sock_net(sk), &xmitq);
2415 	return 0;
2416 }
2417 
2418 /**
2419  * tipc_sk_enqueue - extract all buffers with destination 'dport' from
2420  *                   inputq and try adding them to socket or backlog queue
2421  * @inputq: list of incoming buffers with potentially different destinations
2422  * @sk: socket where the buffers should be enqueued
2423  * @dport: port number for the socket
2424  * @xmitq: output queue
2425  *
2426  * Caller must hold socket lock
2427  */
2428 static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
2429 			    u32 dport, struct sk_buff_head *xmitq)
2430 {
2431 	unsigned long time_limit = jiffies + usecs_to_jiffies(20000);
2432 	struct sk_buff *skb;
2433 	unsigned int lim;
2434 	atomic_t *dcnt;
2435 	u32 onode;
2436 
2437 	while (skb_queue_len(inputq)) {
2438 		if (unlikely(time_after_eq(jiffies, time_limit)))
2439 			return;
2440 
2441 		skb = tipc_skb_dequeue(inputq, dport);
2442 		if (unlikely(!skb))
2443 			return;
2444 
2445 		/* Add message directly to receive queue if possible */
2446 		if (!sock_owned_by_user(sk)) {
2447 			tipc_sk_filter_rcv(sk, skb, xmitq);
2448 			continue;
2449 		}
2450 
2451 		/* Try backlog, compensating for double-counted bytes */
2452 		dcnt = &tipc_sk(sk)->dupl_rcvcnt;
2453 		if (!sk->sk_backlog.len)
2454 			atomic_set(dcnt, 0);
2455 		lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
2456 		if (likely(!sk_add_backlog(sk, skb, lim))) {
2457 			trace_tipc_sk_overlimit1(sk, skb, TIPC_DUMP_ALL,
2458 						 "bklg & rcvq >90% allocated!");
2459 			continue;
2460 		}
2461 
2462 		trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL, "err_overload!");
2463 		/* Overload => reject message back to sender */
2464 		onode = tipc_own_addr(sock_net(sk));
2465 		atomic_inc(&sk->sk_drops);
2466 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD)) {
2467 			trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_ALL,
2468 					      "@sk_enqueue!");
2469 			__skb_queue_tail(xmitq, skb);
2470 		}
2471 		break;
2472 	}
2473 }
2474 
2475 /**
2476  * tipc_sk_rcv - handle a chain of incoming buffers
2477  * @net: the associated network namespace
2478  * @inputq: buffer list containing the buffers
2479  * Consumes all buffers in list until inputq is empty
2480  * Note: may be called in multiple threads referring to the same queue
2481  */
2482 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq)
2483 {
2484 	struct sk_buff_head xmitq;
2485 	u32 dnode, dport = 0;
2486 	int err;
2487 	struct tipc_sock *tsk;
2488 	struct sock *sk;
2489 	struct sk_buff *skb;
2490 
2491 	__skb_queue_head_init(&xmitq);
2492 	while (skb_queue_len(inputq)) {
2493 		dport = tipc_skb_peek_port(inputq, dport);
2494 		tsk = tipc_sk_lookup(net, dport);
2495 
2496 		if (likely(tsk)) {
2497 			sk = &tsk->sk;
2498 			if (likely(spin_trylock_bh(&sk->sk_lock.slock))) {
2499 				tipc_sk_enqueue(inputq, sk, dport, &xmitq);
2500 				spin_unlock_bh(&sk->sk_lock.slock);
2501 			}
2502 			/* Send pending response/rejected messages, if any */
2503 			tipc_node_distr_xmit(sock_net(sk), &xmitq);
2504 			sock_put(sk);
2505 			continue;
2506 		}
2507 		/* No destination socket => dequeue skb if still there */
2508 		skb = tipc_skb_dequeue(inputq, dport);
2509 		if (!skb)
2510 			return;
2511 
2512 		/* Try secondary lookup if unresolved named message */
2513 		err = TIPC_ERR_NO_PORT;
2514 		if (tipc_msg_lookup_dest(net, skb, &err))
2515 			goto xmit;
2516 
2517 		/* Prepare for message rejection */
2518 		if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err))
2519 			continue;
2520 
2521 		trace_tipc_sk_rej_msg(NULL, skb, TIPC_DUMP_NONE, "@sk_rcv!");
2522 xmit:
2523 		dnode = msg_destnode(buf_msg(skb));
2524 		tipc_node_xmit_skb(net, skb, dnode, dport);
2525 	}
2526 }
2527 
2528 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
2529 {
2530 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2531 	struct sock *sk = sock->sk;
2532 	int done;
2533 
2534 	do {
2535 		int err = sock_error(sk);
2536 		if (err)
2537 			return err;
2538 		if (!*timeo_p)
2539 			return -ETIMEDOUT;
2540 		if (signal_pending(current))
2541 			return sock_intr_errno(*timeo_p);
2542 		if (sk->sk_state == TIPC_DISCONNECTING)
2543 			break;
2544 
2545 		add_wait_queue(sk_sleep(sk), &wait);
2546 		done = sk_wait_event(sk, timeo_p, tipc_sk_connected(sk),
2547 				     &wait);
2548 		remove_wait_queue(sk_sleep(sk), &wait);
2549 	} while (!done);
2550 	return 0;
2551 }
2552 
2553 static bool tipc_sockaddr_is_sane(struct sockaddr_tipc *addr)
2554 {
2555 	if (addr->family != AF_TIPC)
2556 		return false;
2557 	if (addr->addrtype == TIPC_SERVICE_RANGE)
2558 		return (addr->addr.nameseq.lower <= addr->addr.nameseq.upper);
2559 	return (addr->addrtype == TIPC_SERVICE_ADDR ||
2560 		addr->addrtype == TIPC_SOCKET_ADDR);
2561 }
2562 
2563 /**
2564  * tipc_connect - establish a connection to another TIPC port
2565  * @sock: socket structure
2566  * @dest: socket address for destination port
2567  * @destlen: size of socket address data structure
2568  * @flags: file-related flags associated with socket
2569  *
2570  * Return: 0 on success, errno otherwise
2571  */
2572 static int tipc_connect(struct socket *sock, struct sockaddr *dest,
2573 			int destlen, int flags)
2574 {
2575 	struct sock *sk = sock->sk;
2576 	struct tipc_sock *tsk = tipc_sk(sk);
2577 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
2578 	struct msghdr m = {NULL,};
2579 	long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout;
2580 	int previous;
2581 	int res = 0;
2582 
2583 	if (destlen != sizeof(struct sockaddr_tipc))
2584 		return -EINVAL;
2585 
2586 	lock_sock(sk);
2587 
2588 	if (tsk->group) {
2589 		res = -EINVAL;
2590 		goto exit;
2591 	}
2592 
2593 	if (dst->family == AF_UNSPEC) {
2594 		memset(&tsk->peer, 0, sizeof(struct sockaddr_tipc));
2595 		if (!tipc_sk_type_connectionless(sk))
2596 			res = -EINVAL;
2597 		goto exit;
2598 	}
2599 	if (!tipc_sockaddr_is_sane(dst)) {
2600 		res = -EINVAL;
2601 		goto exit;
2602 	}
2603 	/* DGRAM/RDM connect(), just save the destaddr */
2604 	if (tipc_sk_type_connectionless(sk)) {
2605 		memcpy(&tsk->peer, dest, destlen);
2606 		goto exit;
2607 	} else if (dst->addrtype == TIPC_SERVICE_RANGE) {
2608 		res = -EINVAL;
2609 		goto exit;
2610 	}
2611 
2612 	previous = sk->sk_state;
2613 
2614 	switch (sk->sk_state) {
2615 	case TIPC_OPEN:
2616 		/* Send a 'SYN-' to destination */
2617 		m.msg_name = dest;
2618 		m.msg_namelen = destlen;
2619 		iov_iter_kvec(&m.msg_iter, ITER_SOURCE, NULL, 0, 0);
2620 
2621 		/* If connect is in non-blocking case, set MSG_DONTWAIT to
2622 		 * indicate send_msg() is never blocked.
2623 		 */
2624 		if (!timeout)
2625 			m.msg_flags = MSG_DONTWAIT;
2626 
2627 		res = __tipc_sendmsg(sock, &m, 0);
2628 		if ((res < 0) && (res != -EWOULDBLOCK))
2629 			goto exit;
2630 
2631 		/* Just entered TIPC_CONNECTING state; the only
2632 		 * difference is that return value in non-blocking
2633 		 * case is EINPROGRESS, rather than EALREADY.
2634 		 */
2635 		res = -EINPROGRESS;
2636 		fallthrough;
2637 	case TIPC_CONNECTING:
2638 		if (!timeout) {
2639 			if (previous == TIPC_CONNECTING)
2640 				res = -EALREADY;
2641 			goto exit;
2642 		}
2643 		timeout = msecs_to_jiffies(timeout);
2644 		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
2645 		res = tipc_wait_for_connect(sock, &timeout);
2646 		break;
2647 	case TIPC_ESTABLISHED:
2648 		res = -EISCONN;
2649 		break;
2650 	default:
2651 		res = -EINVAL;
2652 	}
2653 
2654 exit:
2655 	release_sock(sk);
2656 	return res;
2657 }
2658 
2659 /**
2660  * tipc_listen - allow socket to listen for incoming connections
2661  * @sock: socket structure
2662  * @len: (unused)
2663  *
2664  * Return: 0 on success, errno otherwise
2665  */
2666 static int tipc_listen(struct socket *sock, int len)
2667 {
2668 	struct sock *sk = sock->sk;
2669 	int res;
2670 
2671 	lock_sock(sk);
2672 	res = tipc_set_sk_state(sk, TIPC_LISTEN);
2673 	release_sock(sk);
2674 
2675 	return res;
2676 }
2677 
2678 static int tipc_wait_for_accept(struct socket *sock, long timeo)
2679 {
2680 	struct sock *sk = sock->sk;
2681 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2682 	int err;
2683 
2684 	/* True wake-one mechanism for incoming connections: only
2685 	 * one process gets woken up, not the 'whole herd'.
2686 	 * Since we do not 'race & poll' for established sockets
2687 	 * anymore, the common case will execute the loop only once.
2688 	*/
2689 	for (;;) {
2690 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
2691 			add_wait_queue(sk_sleep(sk), &wait);
2692 			release_sock(sk);
2693 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
2694 			lock_sock(sk);
2695 			remove_wait_queue(sk_sleep(sk), &wait);
2696 		}
2697 		err = 0;
2698 		if (!skb_queue_empty(&sk->sk_receive_queue))
2699 			break;
2700 		err = -EAGAIN;
2701 		if (!timeo)
2702 			break;
2703 		err = sock_intr_errno(timeo);
2704 		if (signal_pending(current))
2705 			break;
2706 	}
2707 	return err;
2708 }
2709 
2710 /**
2711  * tipc_accept - wait for connection request
2712  * @sock: listening socket
2713  * @new_sock: new socket that is to be connected
2714  * @flags: file-related flags associated with socket
2715  * @kern: caused by kernel or by userspace?
2716  *
2717  * Return: 0 on success, errno otherwise
2718  */
2719 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
2720 		       bool kern)
2721 {
2722 	struct sock *new_sk, *sk = sock->sk;
2723 	struct tipc_sock *new_tsock;
2724 	struct msghdr m = {NULL,};
2725 	struct tipc_msg *msg;
2726 	struct sk_buff *buf;
2727 	long timeo;
2728 	int res;
2729 
2730 	lock_sock(sk);
2731 
2732 	if (sk->sk_state != TIPC_LISTEN) {
2733 		res = -EINVAL;
2734 		goto exit;
2735 	}
2736 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2737 	res = tipc_wait_for_accept(sock, timeo);
2738 	if (res)
2739 		goto exit;
2740 
2741 	buf = skb_peek(&sk->sk_receive_queue);
2742 
2743 	res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, kern);
2744 	if (res)
2745 		goto exit;
2746 	security_sk_clone(sock->sk, new_sock->sk);
2747 
2748 	new_sk = new_sock->sk;
2749 	new_tsock = tipc_sk(new_sk);
2750 	msg = buf_msg(buf);
2751 
2752 	/* we lock on new_sk; but lockdep sees the lock on sk */
2753 	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
2754 
2755 	/*
2756 	 * Reject any stray messages received by new socket
2757 	 * before the socket lock was taken (very, very unlikely)
2758 	 */
2759 	tsk_rej_rx_queue(new_sk, TIPC_ERR_NO_PORT);
2760 
2761 	/* Connect new socket to it's peer */
2762 	tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg));
2763 
2764 	tsk_set_importance(new_sk, msg_importance(msg));
2765 	if (msg_named(msg)) {
2766 		new_tsock->conn_addrtype = TIPC_SERVICE_ADDR;
2767 		msg_set_nametype(&new_tsock->phdr, msg_nametype(msg));
2768 		msg_set_nameinst(&new_tsock->phdr, msg_nameinst(msg));
2769 	}
2770 
2771 	/*
2772 	 * Respond to 'SYN-' by discarding it & returning 'ACK'.
2773 	 * Respond to 'SYN+' by queuing it on new socket & returning 'ACK'.
2774 	 */
2775 	if (!msg_data_sz(msg)) {
2776 		tsk_advance_rx_queue(sk);
2777 	} else {
2778 		__skb_dequeue(&sk->sk_receive_queue);
2779 		__skb_queue_head(&new_sk->sk_receive_queue, buf);
2780 		skb_set_owner_r(buf, new_sk);
2781 	}
2782 	iov_iter_kvec(&m.msg_iter, ITER_SOURCE, NULL, 0, 0);
2783 	__tipc_sendstream(new_sock, &m, 0);
2784 	release_sock(new_sk);
2785 exit:
2786 	release_sock(sk);
2787 	return res;
2788 }
2789 
2790 /**
2791  * tipc_shutdown - shutdown socket connection
2792  * @sock: socket structure
2793  * @how: direction to close (must be SHUT_RDWR)
2794  *
2795  * Terminates connection (if necessary), then purges socket's receive queue.
2796  *
2797  * Return: 0 on success, errno otherwise
2798  */
2799 static int tipc_shutdown(struct socket *sock, int how)
2800 {
2801 	struct sock *sk = sock->sk;
2802 	int res;
2803 
2804 	if (how != SHUT_RDWR)
2805 		return -EINVAL;
2806 
2807 	lock_sock(sk);
2808 
2809 	trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " ");
2810 	__tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
2811 	sk->sk_shutdown = SHUTDOWN_MASK;
2812 
2813 	if (sk->sk_state == TIPC_DISCONNECTING) {
2814 		/* Discard any unreceived messages */
2815 		__skb_queue_purge(&sk->sk_receive_queue);
2816 
2817 		res = 0;
2818 	} else {
2819 		res = -ENOTCONN;
2820 	}
2821 	/* Wake up anyone sleeping in poll. */
2822 	sk->sk_state_change(sk);
2823 
2824 	release_sock(sk);
2825 	return res;
2826 }
2827 
2828 static void tipc_sk_check_probing_state(struct sock *sk,
2829 					struct sk_buff_head *list)
2830 {
2831 	struct tipc_sock *tsk = tipc_sk(sk);
2832 	u32 pnode = tsk_peer_node(tsk);
2833 	u32 pport = tsk_peer_port(tsk);
2834 	u32 self = tsk_own_node(tsk);
2835 	u32 oport = tsk->portid;
2836 	struct sk_buff *skb;
2837 
2838 	if (tsk->probe_unacked) {
2839 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2840 		sk->sk_err = ECONNABORTED;
2841 		tipc_node_remove_conn(sock_net(sk), pnode, pport);
2842 		sk->sk_state_change(sk);
2843 		return;
2844 	}
2845 	/* Prepare new probe */
2846 	skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE, INT_H_SIZE, 0,
2847 			      pnode, self, pport, oport, TIPC_OK);
2848 	if (skb)
2849 		__skb_queue_tail(list, skb);
2850 	tsk->probe_unacked = true;
2851 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
2852 }
2853 
2854 static void tipc_sk_retry_connect(struct sock *sk, struct sk_buff_head *list)
2855 {
2856 	struct tipc_sock *tsk = tipc_sk(sk);
2857 
2858 	/* Try again later if dest link is congested */
2859 	if (tsk->cong_link_cnt) {
2860 		sk_reset_timer(sk, &sk->sk_timer,
2861 			       jiffies + msecs_to_jiffies(100));
2862 		return;
2863 	}
2864 	/* Prepare SYN for retransmit */
2865 	tipc_msg_skb_clone(&sk->sk_write_queue, list);
2866 }
2867 
2868 static void tipc_sk_timeout(struct timer_list *t)
2869 {
2870 	struct sock *sk = from_timer(sk, t, sk_timer);
2871 	struct tipc_sock *tsk = tipc_sk(sk);
2872 	u32 pnode = tsk_peer_node(tsk);
2873 	struct sk_buff_head list;
2874 	int rc = 0;
2875 
2876 	__skb_queue_head_init(&list);
2877 	bh_lock_sock(sk);
2878 
2879 	/* Try again later if socket is busy */
2880 	if (sock_owned_by_user(sk)) {
2881 		sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 20);
2882 		bh_unlock_sock(sk);
2883 		sock_put(sk);
2884 		return;
2885 	}
2886 
2887 	if (sk->sk_state == TIPC_ESTABLISHED)
2888 		tipc_sk_check_probing_state(sk, &list);
2889 	else if (sk->sk_state == TIPC_CONNECTING)
2890 		tipc_sk_retry_connect(sk, &list);
2891 
2892 	bh_unlock_sock(sk);
2893 
2894 	if (!skb_queue_empty(&list))
2895 		rc = tipc_node_xmit(sock_net(sk), &list, pnode, tsk->portid);
2896 
2897 	/* SYN messages may cause link congestion */
2898 	if (rc == -ELINKCONG) {
2899 		tipc_dest_push(&tsk->cong_links, pnode, 0);
2900 		tsk->cong_link_cnt = 1;
2901 	}
2902 	sock_put(sk);
2903 }
2904 
2905 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2906 {
2907 	struct sock *sk = &tsk->sk;
2908 	struct net *net = sock_net(sk);
2909 	struct tipc_socket_addr skaddr;
2910 	struct publication *p;
2911 	u32 key;
2912 
2913 	if (tipc_sk_connected(sk))
2914 		return -EINVAL;
2915 	key = tsk->portid + tsk->pub_count + 1;
2916 	if (key == tsk->portid)
2917 		return -EADDRINUSE;
2918 	skaddr.ref = tsk->portid;
2919 	skaddr.node = tipc_own_addr(net);
2920 	p = tipc_nametbl_publish(net, ua, &skaddr, key);
2921 	if (unlikely(!p))
2922 		return -EINVAL;
2923 
2924 	list_add(&p->binding_sock, &tsk->publications);
2925 	tsk->pub_count++;
2926 	tsk->published = true;
2927 	return 0;
2928 }
2929 
2930 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2931 {
2932 	struct net *net = sock_net(&tsk->sk);
2933 	struct publication *safe, *p;
2934 	struct tipc_uaddr _ua;
2935 	int rc = -EINVAL;
2936 
2937 	list_for_each_entry_safe(p, safe, &tsk->publications, binding_sock) {
2938 		if (!ua) {
2939 			tipc_uaddr(&_ua, TIPC_SERVICE_RANGE, p->scope,
2940 				   p->sr.type, p->sr.lower, p->sr.upper);
2941 			tipc_nametbl_withdraw(net, &_ua, &p->sk, p->key);
2942 			continue;
2943 		}
2944 		/* Unbind specific publication */
2945 		if (p->scope != ua->scope)
2946 			continue;
2947 		if (p->sr.type != ua->sr.type)
2948 			continue;
2949 		if (p->sr.lower != ua->sr.lower)
2950 			continue;
2951 		if (p->sr.upper != ua->sr.upper)
2952 			break;
2953 		tipc_nametbl_withdraw(net, ua, &p->sk, p->key);
2954 		rc = 0;
2955 		break;
2956 	}
2957 	if (list_empty(&tsk->publications)) {
2958 		tsk->published = 0;
2959 		rc = 0;
2960 	}
2961 	return rc;
2962 }
2963 
2964 /* tipc_sk_reinit: set non-zero address in all existing sockets
2965  *                 when we go from standalone to network mode.
2966  */
2967 void tipc_sk_reinit(struct net *net)
2968 {
2969 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2970 	struct rhashtable_iter iter;
2971 	struct tipc_sock *tsk;
2972 	struct tipc_msg *msg;
2973 
2974 	rhashtable_walk_enter(&tn->sk_rht, &iter);
2975 
2976 	do {
2977 		rhashtable_walk_start(&iter);
2978 
2979 		while ((tsk = rhashtable_walk_next(&iter)) && !IS_ERR(tsk)) {
2980 			sock_hold(&tsk->sk);
2981 			rhashtable_walk_stop(&iter);
2982 			lock_sock(&tsk->sk);
2983 			msg = &tsk->phdr;
2984 			msg_set_prevnode(msg, tipc_own_addr(net));
2985 			msg_set_orignode(msg, tipc_own_addr(net));
2986 			release_sock(&tsk->sk);
2987 			rhashtable_walk_start(&iter);
2988 			sock_put(&tsk->sk);
2989 		}
2990 
2991 		rhashtable_walk_stop(&iter);
2992 	} while (tsk == ERR_PTR(-EAGAIN));
2993 
2994 	rhashtable_walk_exit(&iter);
2995 }
2996 
2997 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)
2998 {
2999 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3000 	struct tipc_sock *tsk;
3001 
3002 	rcu_read_lock();
3003 	tsk = rhashtable_lookup(&tn->sk_rht, &portid, tsk_rht_params);
3004 	if (tsk)
3005 		sock_hold(&tsk->sk);
3006 	rcu_read_unlock();
3007 
3008 	return tsk;
3009 }
3010 
3011 static int tipc_sk_insert(struct tipc_sock *tsk)
3012 {
3013 	struct sock *sk = &tsk->sk;
3014 	struct net *net = sock_net(sk);
3015 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3016 	u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1;
3017 	u32 portid = get_random_u32_below(remaining) + TIPC_MIN_PORT;
3018 
3019 	while (remaining--) {
3020 		portid++;
3021 		if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT))
3022 			portid = TIPC_MIN_PORT;
3023 		tsk->portid = portid;
3024 		sock_hold(&tsk->sk);
3025 		if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node,
3026 						   tsk_rht_params))
3027 			return 0;
3028 		sock_put(&tsk->sk);
3029 	}
3030 
3031 	return -1;
3032 }
3033 
3034 static void tipc_sk_remove(struct tipc_sock *tsk)
3035 {
3036 	struct sock *sk = &tsk->sk;
3037 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
3038 
3039 	if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) {
3040 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
3041 		__sock_put(sk);
3042 	}
3043 }
3044 
3045 static const struct rhashtable_params tsk_rht_params = {
3046 	.nelem_hint = 192,
3047 	.head_offset = offsetof(struct tipc_sock, node),
3048 	.key_offset = offsetof(struct tipc_sock, portid),
3049 	.key_len = sizeof(u32), /* portid */
3050 	.max_size = 1048576,
3051 	.min_size = 256,
3052 	.automatic_shrinking = true,
3053 };
3054 
3055 int tipc_sk_rht_init(struct net *net)
3056 {
3057 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3058 
3059 	return rhashtable_init(&tn->sk_rht, &tsk_rht_params);
3060 }
3061 
3062 void tipc_sk_rht_destroy(struct net *net)
3063 {
3064 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3065 
3066 	/* Wait for socket readers to complete */
3067 	synchronize_net();
3068 
3069 	rhashtable_destroy(&tn->sk_rht);
3070 }
3071 
3072 static int tipc_sk_join(struct tipc_sock *tsk, struct tipc_group_req *mreq)
3073 {
3074 	struct net *net = sock_net(&tsk->sk);
3075 	struct tipc_group *grp = tsk->group;
3076 	struct tipc_msg *hdr = &tsk->phdr;
3077 	struct tipc_uaddr ua;
3078 	int rc;
3079 
3080 	if (mreq->type < TIPC_RESERVED_TYPES)
3081 		return -EACCES;
3082 	if (mreq->scope > TIPC_NODE_SCOPE)
3083 		return -EINVAL;
3084 	if (mreq->scope != TIPC_NODE_SCOPE)
3085 		mreq->scope = TIPC_CLUSTER_SCOPE;
3086 	if (grp)
3087 		return -EACCES;
3088 	grp = tipc_group_create(net, tsk->portid, mreq, &tsk->group_is_open);
3089 	if (!grp)
3090 		return -ENOMEM;
3091 	tsk->group = grp;
3092 	msg_set_lookup_scope(hdr, mreq->scope);
3093 	msg_set_nametype(hdr, mreq->type);
3094 	msg_set_dest_droppable(hdr, true);
3095 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, mreq->scope,
3096 		   mreq->type, mreq->instance, mreq->instance);
3097 	tipc_nametbl_build_group(net, grp, &ua);
3098 	rc = tipc_sk_publish(tsk, &ua);
3099 	if (rc) {
3100 		tipc_group_delete(net, grp);
3101 		tsk->group = NULL;
3102 		return rc;
3103 	}
3104 	/* Eliminate any risk that a broadcast overtakes sent JOINs */
3105 	tsk->mc_method.rcast = true;
3106 	tsk->mc_method.mandatory = true;
3107 	tipc_group_join(net, grp, &tsk->sk.sk_rcvbuf);
3108 	return rc;
3109 }
3110 
3111 static int tipc_sk_leave(struct tipc_sock *tsk)
3112 {
3113 	struct net *net = sock_net(&tsk->sk);
3114 	struct tipc_group *grp = tsk->group;
3115 	struct tipc_uaddr ua;
3116 	int scope;
3117 
3118 	if (!grp)
3119 		return -EINVAL;
3120 	ua.addrtype = TIPC_SERVICE_RANGE;
3121 	tipc_group_self(grp, &ua.sr, &scope);
3122 	ua.scope = scope;
3123 	tipc_group_delete(net, grp);
3124 	tsk->group = NULL;
3125 	tipc_sk_withdraw(tsk, &ua);
3126 	return 0;
3127 }
3128 
3129 /**
3130  * tipc_setsockopt - set socket option
3131  * @sock: socket structure
3132  * @lvl: option level
3133  * @opt: option identifier
3134  * @ov: pointer to new option value
3135  * @ol: length of option value
3136  *
3137  * For stream sockets only, accepts and ignores all IPPROTO_TCP options
3138  * (to ease compatibility).
3139  *
3140  * Return: 0 on success, errno otherwise
3141  */
3142 static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
3143 			   sockptr_t ov, unsigned int ol)
3144 {
3145 	struct sock *sk = sock->sk;
3146 	struct tipc_sock *tsk = tipc_sk(sk);
3147 	struct tipc_group_req mreq;
3148 	u32 value = 0;
3149 	int res = 0;
3150 
3151 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
3152 		return 0;
3153 	if (lvl != SOL_TIPC)
3154 		return -ENOPROTOOPT;
3155 
3156 	switch (opt) {
3157 	case TIPC_IMPORTANCE:
3158 	case TIPC_SRC_DROPPABLE:
3159 	case TIPC_DEST_DROPPABLE:
3160 	case TIPC_CONN_TIMEOUT:
3161 	case TIPC_NODELAY:
3162 		if (ol < sizeof(value))
3163 			return -EINVAL;
3164 		if (copy_from_sockptr(&value, ov, sizeof(u32)))
3165 			return -EFAULT;
3166 		break;
3167 	case TIPC_GROUP_JOIN:
3168 		if (ol < sizeof(mreq))
3169 			return -EINVAL;
3170 		if (copy_from_sockptr(&mreq, ov, sizeof(mreq)))
3171 			return -EFAULT;
3172 		break;
3173 	default:
3174 		if (!sockptr_is_null(ov) || ol)
3175 			return -EINVAL;
3176 	}
3177 
3178 	lock_sock(sk);
3179 
3180 	switch (opt) {
3181 	case TIPC_IMPORTANCE:
3182 		res = tsk_set_importance(sk, value);
3183 		break;
3184 	case TIPC_SRC_DROPPABLE:
3185 		if (sock->type != SOCK_STREAM)
3186 			tsk_set_unreliable(tsk, value);
3187 		else
3188 			res = -ENOPROTOOPT;
3189 		break;
3190 	case TIPC_DEST_DROPPABLE:
3191 		tsk_set_unreturnable(tsk, value);
3192 		break;
3193 	case TIPC_CONN_TIMEOUT:
3194 		tipc_sk(sk)->conn_timeout = value;
3195 		break;
3196 	case TIPC_MCAST_BROADCAST:
3197 		tsk->mc_method.rcast = false;
3198 		tsk->mc_method.mandatory = true;
3199 		break;
3200 	case TIPC_MCAST_REPLICAST:
3201 		tsk->mc_method.rcast = true;
3202 		tsk->mc_method.mandatory = true;
3203 		break;
3204 	case TIPC_GROUP_JOIN:
3205 		res = tipc_sk_join(tsk, &mreq);
3206 		break;
3207 	case TIPC_GROUP_LEAVE:
3208 		res = tipc_sk_leave(tsk);
3209 		break;
3210 	case TIPC_NODELAY:
3211 		tsk->nodelay = !!value;
3212 		tsk_set_nagle(tsk);
3213 		break;
3214 	default:
3215 		res = -EINVAL;
3216 	}
3217 
3218 	release_sock(sk);
3219 
3220 	return res;
3221 }
3222 
3223 /**
3224  * tipc_getsockopt - get socket option
3225  * @sock: socket structure
3226  * @lvl: option level
3227  * @opt: option identifier
3228  * @ov: receptacle for option value
3229  * @ol: receptacle for length of option value
3230  *
3231  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
3232  * (to ease compatibility).
3233  *
3234  * Return: 0 on success, errno otherwise
3235  */
3236 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
3237 			   char __user *ov, int __user *ol)
3238 {
3239 	struct sock *sk = sock->sk;
3240 	struct tipc_sock *tsk = tipc_sk(sk);
3241 	struct tipc_service_range seq;
3242 	int len, scope;
3243 	u32 value;
3244 	int res;
3245 
3246 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
3247 		return put_user(0, ol);
3248 	if (lvl != SOL_TIPC)
3249 		return -ENOPROTOOPT;
3250 	res = get_user(len, ol);
3251 	if (res)
3252 		return res;
3253 
3254 	lock_sock(sk);
3255 
3256 	switch (opt) {
3257 	case TIPC_IMPORTANCE:
3258 		value = tsk_importance(tsk);
3259 		break;
3260 	case TIPC_SRC_DROPPABLE:
3261 		value = tsk_unreliable(tsk);
3262 		break;
3263 	case TIPC_DEST_DROPPABLE:
3264 		value = tsk_unreturnable(tsk);
3265 		break;
3266 	case TIPC_CONN_TIMEOUT:
3267 		value = tsk->conn_timeout;
3268 		/* no need to set "res", since already 0 at this point */
3269 		break;
3270 	case TIPC_NODE_RECVQ_DEPTH:
3271 		value = 0; /* was tipc_queue_size, now obsolete */
3272 		break;
3273 	case TIPC_SOCK_RECVQ_DEPTH:
3274 		value = skb_queue_len(&sk->sk_receive_queue);
3275 		break;
3276 	case TIPC_SOCK_RECVQ_USED:
3277 		value = sk_rmem_alloc_get(sk);
3278 		break;
3279 	case TIPC_GROUP_JOIN:
3280 		seq.type = 0;
3281 		if (tsk->group)
3282 			tipc_group_self(tsk->group, &seq, &scope);
3283 		value = seq.type;
3284 		break;
3285 	default:
3286 		res = -EINVAL;
3287 	}
3288 
3289 	release_sock(sk);
3290 
3291 	if (res)
3292 		return res;	/* "get" failed */
3293 
3294 	if (len < sizeof(value))
3295 		return -EINVAL;
3296 
3297 	if (copy_to_user(ov, &value, sizeof(value)))
3298 		return -EFAULT;
3299 
3300 	return put_user(sizeof(value), ol);
3301 }
3302 
3303 static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3304 {
3305 	struct net *net = sock_net(sock->sk);
3306 	struct tipc_sioc_nodeid_req nr = {0};
3307 	struct tipc_sioc_ln_req lnr;
3308 	void __user *argp = (void __user *)arg;
3309 
3310 	switch (cmd) {
3311 	case SIOCGETLINKNAME:
3312 		if (copy_from_user(&lnr, argp, sizeof(lnr)))
3313 			return -EFAULT;
3314 		if (!tipc_node_get_linkname(net,
3315 					    lnr.bearer_id & 0xffff, lnr.peer,
3316 					    lnr.linkname, TIPC_MAX_LINK_NAME)) {
3317 			if (copy_to_user(argp, &lnr, sizeof(lnr)))
3318 				return -EFAULT;
3319 			return 0;
3320 		}
3321 		return -EADDRNOTAVAIL;
3322 	case SIOCGETNODEID:
3323 		if (copy_from_user(&nr, argp, sizeof(nr)))
3324 			return -EFAULT;
3325 		if (!tipc_node_get_id(net, nr.peer, nr.node_id))
3326 			return -EADDRNOTAVAIL;
3327 		if (copy_to_user(argp, &nr, sizeof(nr)))
3328 			return -EFAULT;
3329 		return 0;
3330 	default:
3331 		return -ENOIOCTLCMD;
3332 	}
3333 }
3334 
3335 static int tipc_socketpair(struct socket *sock1, struct socket *sock2)
3336 {
3337 	struct tipc_sock *tsk2 = tipc_sk(sock2->sk);
3338 	struct tipc_sock *tsk1 = tipc_sk(sock1->sk);
3339 	u32 onode = tipc_own_addr(sock_net(sock1->sk));
3340 
3341 	tsk1->peer.family = AF_TIPC;
3342 	tsk1->peer.addrtype = TIPC_SOCKET_ADDR;
3343 	tsk1->peer.scope = TIPC_NODE_SCOPE;
3344 	tsk1->peer.addr.id.ref = tsk2->portid;
3345 	tsk1->peer.addr.id.node = onode;
3346 	tsk2->peer.family = AF_TIPC;
3347 	tsk2->peer.addrtype = TIPC_SOCKET_ADDR;
3348 	tsk2->peer.scope = TIPC_NODE_SCOPE;
3349 	tsk2->peer.addr.id.ref = tsk1->portid;
3350 	tsk2->peer.addr.id.node = onode;
3351 
3352 	tipc_sk_finish_conn(tsk1, tsk2->portid, onode);
3353 	tipc_sk_finish_conn(tsk2, tsk1->portid, onode);
3354 	return 0;
3355 }
3356 
3357 /* Protocol switches for the various types of TIPC sockets */
3358 
3359 static const struct proto_ops msg_ops = {
3360 	.owner		= THIS_MODULE,
3361 	.family		= AF_TIPC,
3362 	.release	= tipc_release,
3363 	.bind		= tipc_bind,
3364 	.connect	= tipc_connect,
3365 	.socketpair	= tipc_socketpair,
3366 	.accept		= sock_no_accept,
3367 	.getname	= tipc_getname,
3368 	.poll		= tipc_poll,
3369 	.ioctl		= tipc_ioctl,
3370 	.listen		= sock_no_listen,
3371 	.shutdown	= tipc_shutdown,
3372 	.setsockopt	= tipc_setsockopt,
3373 	.getsockopt	= tipc_getsockopt,
3374 	.sendmsg	= tipc_sendmsg,
3375 	.recvmsg	= tipc_recvmsg,
3376 	.mmap		= sock_no_mmap,
3377 };
3378 
3379 static const struct proto_ops packet_ops = {
3380 	.owner		= THIS_MODULE,
3381 	.family		= AF_TIPC,
3382 	.release	= tipc_release,
3383 	.bind		= tipc_bind,
3384 	.connect	= tipc_connect,
3385 	.socketpair	= tipc_socketpair,
3386 	.accept		= tipc_accept,
3387 	.getname	= tipc_getname,
3388 	.poll		= tipc_poll,
3389 	.ioctl		= tipc_ioctl,
3390 	.listen		= tipc_listen,
3391 	.shutdown	= tipc_shutdown,
3392 	.setsockopt	= tipc_setsockopt,
3393 	.getsockopt	= tipc_getsockopt,
3394 	.sendmsg	= tipc_send_packet,
3395 	.recvmsg	= tipc_recvmsg,
3396 	.mmap		= sock_no_mmap,
3397 };
3398 
3399 static const struct proto_ops stream_ops = {
3400 	.owner		= THIS_MODULE,
3401 	.family		= AF_TIPC,
3402 	.release	= tipc_release,
3403 	.bind		= tipc_bind,
3404 	.connect	= tipc_connect,
3405 	.socketpair	= tipc_socketpair,
3406 	.accept		= tipc_accept,
3407 	.getname	= tipc_getname,
3408 	.poll		= tipc_poll,
3409 	.ioctl		= tipc_ioctl,
3410 	.listen		= tipc_listen,
3411 	.shutdown	= tipc_shutdown,
3412 	.setsockopt	= tipc_setsockopt,
3413 	.getsockopt	= tipc_getsockopt,
3414 	.sendmsg	= tipc_sendstream,
3415 	.recvmsg	= tipc_recvstream,
3416 	.mmap		= sock_no_mmap,
3417 };
3418 
3419 static const struct net_proto_family tipc_family_ops = {
3420 	.owner		= THIS_MODULE,
3421 	.family		= AF_TIPC,
3422 	.create		= tipc_sk_create
3423 };
3424 
3425 static struct proto tipc_proto = {
3426 	.name		= "TIPC",
3427 	.owner		= THIS_MODULE,
3428 	.obj_size	= sizeof(struct tipc_sock),
3429 	.sysctl_rmem	= sysctl_tipc_rmem
3430 };
3431 
3432 /**
3433  * tipc_socket_init - initialize TIPC socket interface
3434  *
3435  * Return: 0 on success, errno otherwise
3436  */
3437 int tipc_socket_init(void)
3438 {
3439 	int res;
3440 
3441 	res = proto_register(&tipc_proto, 1);
3442 	if (res) {
3443 		pr_err("Failed to register TIPC protocol type\n");
3444 		goto out;
3445 	}
3446 
3447 	res = sock_register(&tipc_family_ops);
3448 	if (res) {
3449 		pr_err("Failed to register TIPC socket type\n");
3450 		proto_unregister(&tipc_proto);
3451 		goto out;
3452 	}
3453  out:
3454 	return res;
3455 }
3456 
3457 /**
3458  * tipc_socket_stop - stop TIPC socket interface
3459  */
3460 void tipc_socket_stop(void)
3461 {
3462 	sock_unregister(tipc_family_ops.family);
3463 	proto_unregister(&tipc_proto);
3464 }
3465 
3466 /* Caller should hold socket lock for the passed tipc socket. */
3467 static int __tipc_nl_add_sk_con(struct sk_buff *skb, struct tipc_sock *tsk)
3468 {
3469 	u32 peer_node, peer_port;
3470 	u32 conn_type, conn_instance;
3471 	struct nlattr *nest;
3472 
3473 	peer_node = tsk_peer_node(tsk);
3474 	peer_port = tsk_peer_port(tsk);
3475 	conn_type = msg_nametype(&tsk->phdr);
3476 	conn_instance = msg_nameinst(&tsk->phdr);
3477 	nest = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_CON);
3478 	if (!nest)
3479 		return -EMSGSIZE;
3480 
3481 	if (nla_put_u32(skb, TIPC_NLA_CON_NODE, peer_node))
3482 		goto msg_full;
3483 	if (nla_put_u32(skb, TIPC_NLA_CON_SOCK, peer_port))
3484 		goto msg_full;
3485 
3486 	if (tsk->conn_addrtype != 0) {
3487 		if (nla_put_flag(skb, TIPC_NLA_CON_FLAG))
3488 			goto msg_full;
3489 		if (nla_put_u32(skb, TIPC_NLA_CON_TYPE, conn_type))
3490 			goto msg_full;
3491 		if (nla_put_u32(skb, TIPC_NLA_CON_INST, conn_instance))
3492 			goto msg_full;
3493 	}
3494 	nla_nest_end(skb, nest);
3495 
3496 	return 0;
3497 
3498 msg_full:
3499 	nla_nest_cancel(skb, nest);
3500 
3501 	return -EMSGSIZE;
3502 }
3503 
3504 static int __tipc_nl_add_sk_info(struct sk_buff *skb, struct tipc_sock
3505 			  *tsk)
3506 {
3507 	struct net *net = sock_net(skb->sk);
3508 	struct sock *sk = &tsk->sk;
3509 
3510 	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid) ||
3511 	    nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tipc_own_addr(net)))
3512 		return -EMSGSIZE;
3513 
3514 	if (tipc_sk_connected(sk)) {
3515 		if (__tipc_nl_add_sk_con(skb, tsk))
3516 			return -EMSGSIZE;
3517 	} else if (!list_empty(&tsk->publications)) {
3518 		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
3519 			return -EMSGSIZE;
3520 	}
3521 	return 0;
3522 }
3523 
3524 /* Caller should hold socket lock for the passed tipc socket. */
3525 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
3526 			    struct tipc_sock *tsk)
3527 {
3528 	struct nlattr *attrs;
3529 	void *hdr;
3530 
3531 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3532 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
3533 	if (!hdr)
3534 		goto msg_cancel;
3535 
3536 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3537 	if (!attrs)
3538 		goto genlmsg_cancel;
3539 
3540 	if (__tipc_nl_add_sk_info(skb, tsk))
3541 		goto attr_msg_cancel;
3542 
3543 	nla_nest_end(skb, attrs);
3544 	genlmsg_end(skb, hdr);
3545 
3546 	return 0;
3547 
3548 attr_msg_cancel:
3549 	nla_nest_cancel(skb, attrs);
3550 genlmsg_cancel:
3551 	genlmsg_cancel(skb, hdr);
3552 msg_cancel:
3553 	return -EMSGSIZE;
3554 }
3555 
3556 int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
3557 		    int (*skb_handler)(struct sk_buff *skb,
3558 				       struct netlink_callback *cb,
3559 				       struct tipc_sock *tsk))
3560 {
3561 	struct rhashtable_iter *iter = (void *)cb->args[4];
3562 	struct tipc_sock *tsk;
3563 	int err;
3564 
3565 	rhashtable_walk_start(iter);
3566 	while ((tsk = rhashtable_walk_next(iter)) != NULL) {
3567 		if (IS_ERR(tsk)) {
3568 			err = PTR_ERR(tsk);
3569 			if (err == -EAGAIN) {
3570 				err = 0;
3571 				continue;
3572 			}
3573 			break;
3574 		}
3575 
3576 		sock_hold(&tsk->sk);
3577 		rhashtable_walk_stop(iter);
3578 		lock_sock(&tsk->sk);
3579 		err = skb_handler(skb, cb, tsk);
3580 		if (err) {
3581 			release_sock(&tsk->sk);
3582 			sock_put(&tsk->sk);
3583 			goto out;
3584 		}
3585 		release_sock(&tsk->sk);
3586 		rhashtable_walk_start(iter);
3587 		sock_put(&tsk->sk);
3588 	}
3589 	rhashtable_walk_stop(iter);
3590 out:
3591 	return skb->len;
3592 }
3593 EXPORT_SYMBOL(tipc_nl_sk_walk);
3594 
3595 int tipc_dump_start(struct netlink_callback *cb)
3596 {
3597 	return __tipc_dump_start(cb, sock_net(cb->skb->sk));
3598 }
3599 EXPORT_SYMBOL(tipc_dump_start);
3600 
3601 int __tipc_dump_start(struct netlink_callback *cb, struct net *net)
3602 {
3603 	/* tipc_nl_name_table_dump() uses cb->args[0...3]. */
3604 	struct rhashtable_iter *iter = (void *)cb->args[4];
3605 	struct tipc_net *tn = tipc_net(net);
3606 
3607 	if (!iter) {
3608 		iter = kmalloc(sizeof(*iter), GFP_KERNEL);
3609 		if (!iter)
3610 			return -ENOMEM;
3611 
3612 		cb->args[4] = (long)iter;
3613 	}
3614 
3615 	rhashtable_walk_enter(&tn->sk_rht, iter);
3616 	return 0;
3617 }
3618 
3619 int tipc_dump_done(struct netlink_callback *cb)
3620 {
3621 	struct rhashtable_iter *hti = (void *)cb->args[4];
3622 
3623 	rhashtable_walk_exit(hti);
3624 	kfree(hti);
3625 	return 0;
3626 }
3627 EXPORT_SYMBOL(tipc_dump_done);
3628 
3629 int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct netlink_callback *cb,
3630 			   struct tipc_sock *tsk, u32 sk_filter_state,
3631 			   u64 (*tipc_diag_gen_cookie)(struct sock *sk))
3632 {
3633 	struct sock *sk = &tsk->sk;
3634 	struct nlattr *attrs;
3635 	struct nlattr *stat;
3636 
3637 	/*filter response w.r.t sk_state*/
3638 	if (!(sk_filter_state & (1 << sk->sk_state)))
3639 		return 0;
3640 
3641 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3642 	if (!attrs)
3643 		goto msg_cancel;
3644 
3645 	if (__tipc_nl_add_sk_info(skb, tsk))
3646 		goto attr_msg_cancel;
3647 
3648 	if (nla_put_u32(skb, TIPC_NLA_SOCK_TYPE, (u32)sk->sk_type) ||
3649 	    nla_put_u32(skb, TIPC_NLA_SOCK_TIPC_STATE, (u32)sk->sk_state) ||
3650 	    nla_put_u32(skb, TIPC_NLA_SOCK_INO, sock_i_ino(sk)) ||
3651 	    nla_put_u32(skb, TIPC_NLA_SOCK_UID,
3652 			from_kuid_munged(sk_user_ns(NETLINK_CB(cb->skb).sk),
3653 					 sock_i_uid(sk))) ||
3654 	    nla_put_u64_64bit(skb, TIPC_NLA_SOCK_COOKIE,
3655 			      tipc_diag_gen_cookie(sk),
3656 			      TIPC_NLA_SOCK_PAD))
3657 		goto attr_msg_cancel;
3658 
3659 	stat = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_STAT);
3660 	if (!stat)
3661 		goto attr_msg_cancel;
3662 
3663 	if (nla_put_u32(skb, TIPC_NLA_SOCK_STAT_RCVQ,
3664 			skb_queue_len(&sk->sk_receive_queue)) ||
3665 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_SENDQ,
3666 			skb_queue_len(&sk->sk_write_queue)) ||
3667 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_DROP,
3668 			atomic_read(&sk->sk_drops)))
3669 		goto stat_msg_cancel;
3670 
3671 	if (tsk->cong_link_cnt &&
3672 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_LINK_CONG))
3673 		goto stat_msg_cancel;
3674 
3675 	if (tsk_conn_cong(tsk) &&
3676 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_CONN_CONG))
3677 		goto stat_msg_cancel;
3678 
3679 	nla_nest_end(skb, stat);
3680 
3681 	if (tsk->group)
3682 		if (tipc_group_fill_sock_diag(tsk->group, skb))
3683 			goto stat_msg_cancel;
3684 
3685 	nla_nest_end(skb, attrs);
3686 
3687 	return 0;
3688 
3689 stat_msg_cancel:
3690 	nla_nest_cancel(skb, stat);
3691 attr_msg_cancel:
3692 	nla_nest_cancel(skb, attrs);
3693 msg_cancel:
3694 	return -EMSGSIZE;
3695 }
3696 EXPORT_SYMBOL(tipc_sk_fill_sock_diag);
3697 
3698 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
3699 {
3700 	return tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk);
3701 }
3702 
3703 /* Caller should hold socket lock for the passed tipc socket. */
3704 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
3705 				 struct netlink_callback *cb,
3706 				 struct publication *publ)
3707 {
3708 	void *hdr;
3709 	struct nlattr *attrs;
3710 
3711 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3712 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET);
3713 	if (!hdr)
3714 		goto msg_cancel;
3715 
3716 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_PUBL);
3717 	if (!attrs)
3718 		goto genlmsg_cancel;
3719 
3720 	if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key))
3721 		goto attr_msg_cancel;
3722 	if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->sr.type))
3723 		goto attr_msg_cancel;
3724 	if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->sr.lower))
3725 		goto attr_msg_cancel;
3726 	if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->sr.upper))
3727 		goto attr_msg_cancel;
3728 
3729 	nla_nest_end(skb, attrs);
3730 	genlmsg_end(skb, hdr);
3731 
3732 	return 0;
3733 
3734 attr_msg_cancel:
3735 	nla_nest_cancel(skb, attrs);
3736 genlmsg_cancel:
3737 	genlmsg_cancel(skb, hdr);
3738 msg_cancel:
3739 	return -EMSGSIZE;
3740 }
3741 
3742 /* Caller should hold socket lock for the passed tipc socket. */
3743 static int __tipc_nl_list_sk_publ(struct sk_buff *skb,
3744 				  struct netlink_callback *cb,
3745 				  struct tipc_sock *tsk, u32 *last_publ)
3746 {
3747 	int err;
3748 	struct publication *p;
3749 
3750 	if (*last_publ) {
3751 		list_for_each_entry(p, &tsk->publications, binding_sock) {
3752 			if (p->key == *last_publ)
3753 				break;
3754 		}
3755 		if (list_entry_is_head(p, &tsk->publications, binding_sock)) {
3756 			/* We never set seq or call nl_dump_check_consistent()
3757 			 * this means that setting prev_seq here will cause the
3758 			 * consistence check to fail in the netlink callback
3759 			 * handler. Resulting in the last NLMSG_DONE message
3760 			 * having the NLM_F_DUMP_INTR flag set.
3761 			 */
3762 			cb->prev_seq = 1;
3763 			*last_publ = 0;
3764 			return -EPIPE;
3765 		}
3766 	} else {
3767 		p = list_first_entry(&tsk->publications, struct publication,
3768 				     binding_sock);
3769 	}
3770 
3771 	list_for_each_entry_from(p, &tsk->publications, binding_sock) {
3772 		err = __tipc_nl_add_sk_publ(skb, cb, p);
3773 		if (err) {
3774 			*last_publ = p->key;
3775 			return err;
3776 		}
3777 	}
3778 	*last_publ = 0;
3779 
3780 	return 0;
3781 }
3782 
3783 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
3784 {
3785 	int err;
3786 	u32 tsk_portid = cb->args[0];
3787 	u32 last_publ = cb->args[1];
3788 	u32 done = cb->args[2];
3789 	struct net *net = sock_net(skb->sk);
3790 	struct tipc_sock *tsk;
3791 
3792 	if (!tsk_portid) {
3793 		struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
3794 		struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
3795 
3796 		if (!attrs[TIPC_NLA_SOCK])
3797 			return -EINVAL;
3798 
3799 		err = nla_parse_nested_deprecated(sock, TIPC_NLA_SOCK_MAX,
3800 						  attrs[TIPC_NLA_SOCK],
3801 						  tipc_nl_sock_policy, NULL);
3802 		if (err)
3803 			return err;
3804 
3805 		if (!sock[TIPC_NLA_SOCK_REF])
3806 			return -EINVAL;
3807 
3808 		tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
3809 	}
3810 
3811 	if (done)
3812 		return 0;
3813 
3814 	tsk = tipc_sk_lookup(net, tsk_portid);
3815 	if (!tsk)
3816 		return -EINVAL;
3817 
3818 	lock_sock(&tsk->sk);
3819 	err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ);
3820 	if (!err)
3821 		done = 1;
3822 	release_sock(&tsk->sk);
3823 	sock_put(&tsk->sk);
3824 
3825 	cb->args[0] = tsk_portid;
3826 	cb->args[1] = last_publ;
3827 	cb->args[2] = done;
3828 
3829 	return skb->len;
3830 }
3831 
3832 /**
3833  * tipc_sk_filtering - check if a socket should be traced
3834  * @sk: the socket to be examined
3835  *
3836  * @sysctl_tipc_sk_filter is used as the socket tuple for filtering:
3837  * (portid, sock type, name type, name lower, name upper)
3838  *
3839  * Return: true if the socket meets the socket tuple data
3840  * (value 0 = 'any') or when there is no tuple set (all = 0),
3841  * otherwise false
3842  */
3843 bool tipc_sk_filtering(struct sock *sk)
3844 {
3845 	struct tipc_sock *tsk;
3846 	struct publication *p;
3847 	u32 _port, _sktype, _type, _lower, _upper;
3848 	u32 type = 0, lower = 0, upper = 0;
3849 
3850 	if (!sk)
3851 		return true;
3852 
3853 	tsk = tipc_sk(sk);
3854 
3855 	_port = sysctl_tipc_sk_filter[0];
3856 	_sktype = sysctl_tipc_sk_filter[1];
3857 	_type = sysctl_tipc_sk_filter[2];
3858 	_lower = sysctl_tipc_sk_filter[3];
3859 	_upper = sysctl_tipc_sk_filter[4];
3860 
3861 	if (!_port && !_sktype && !_type && !_lower && !_upper)
3862 		return true;
3863 
3864 	if (_port)
3865 		return (_port == tsk->portid);
3866 
3867 	if (_sktype && _sktype != sk->sk_type)
3868 		return false;
3869 
3870 	if (tsk->published) {
3871 		p = list_first_entry_or_null(&tsk->publications,
3872 					     struct publication, binding_sock);
3873 		if (p) {
3874 			type = p->sr.type;
3875 			lower = p->sr.lower;
3876 			upper = p->sr.upper;
3877 		}
3878 	}
3879 
3880 	if (!tipc_sk_type_connectionless(sk)) {
3881 		type = msg_nametype(&tsk->phdr);
3882 		lower = msg_nameinst(&tsk->phdr);
3883 		upper = lower;
3884 	}
3885 
3886 	if ((_type && _type != type) || (_lower && _lower != lower) ||
3887 	    (_upper && _upper != upper))
3888 		return false;
3889 
3890 	return true;
3891 }
3892 
3893 u32 tipc_sock_get_portid(struct sock *sk)
3894 {
3895 	return (sk) ? (tipc_sk(sk))->portid : 0;
3896 }
3897 
3898 /**
3899  * tipc_sk_overlimit1 - check if socket rx queue is about to be overloaded,
3900  *			both the rcv and backlog queues are considered
3901  * @sk: tipc sk to be checked
3902  * @skb: tipc msg to be checked
3903  *
3904  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3905  */
3906 
3907 bool tipc_sk_overlimit1(struct sock *sk, struct sk_buff *skb)
3908 {
3909 	atomic_t *dcnt = &tipc_sk(sk)->dupl_rcvcnt;
3910 	unsigned int lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
3911 	unsigned int qsize = sk->sk_backlog.len + sk_rmem_alloc_get(sk);
3912 
3913 	return (qsize > lim * 90 / 100);
3914 }
3915 
3916 /**
3917  * tipc_sk_overlimit2 - check if socket rx queue is about to be overloaded,
3918  *			only the rcv queue is considered
3919  * @sk: tipc sk to be checked
3920  * @skb: tipc msg to be checked
3921  *
3922  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3923  */
3924 
3925 bool tipc_sk_overlimit2(struct sock *sk, struct sk_buff *skb)
3926 {
3927 	unsigned int lim = rcvbuf_limit(sk, skb);
3928 	unsigned int qsize = sk_rmem_alloc_get(sk);
3929 
3930 	return (qsize > lim * 90 / 100);
3931 }
3932 
3933 /**
3934  * tipc_sk_dump - dump TIPC socket
3935  * @sk: tipc sk to be dumped
3936  * @dqueues: bitmask to decide if any socket queue to be dumped?
3937  *           - TIPC_DUMP_NONE: don't dump socket queues
3938  *           - TIPC_DUMP_SK_SNDQ: dump socket send queue
3939  *           - TIPC_DUMP_SK_RCVQ: dump socket rcv queue
3940  *           - TIPC_DUMP_SK_BKLGQ: dump socket backlog queue
3941  *           - TIPC_DUMP_ALL: dump all the socket queues above
3942  * @buf: returned buffer of dump data in format
3943  */
3944 int tipc_sk_dump(struct sock *sk, u16 dqueues, char *buf)
3945 {
3946 	int i = 0;
3947 	size_t sz = (dqueues) ? SK_LMAX : SK_LMIN;
3948 	u32 conn_type, conn_instance;
3949 	struct tipc_sock *tsk;
3950 	struct publication *p;
3951 	bool tsk_connected;
3952 
3953 	if (!sk) {
3954 		i += scnprintf(buf, sz, "sk data: (null)\n");
3955 		return i;
3956 	}
3957 
3958 	tsk = tipc_sk(sk);
3959 	tsk_connected = !tipc_sk_type_connectionless(sk);
3960 
3961 	i += scnprintf(buf, sz, "sk data: %u", sk->sk_type);
3962 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_state);
3963 	i += scnprintf(buf + i, sz - i, " %x", tsk_own_node(tsk));
3964 	i += scnprintf(buf + i, sz - i, " %u", tsk->portid);
3965 	i += scnprintf(buf + i, sz - i, " | %u", tsk_connected);
3966 	if (tsk_connected) {
3967 		i += scnprintf(buf + i, sz - i, " %x", tsk_peer_node(tsk));
3968 		i += scnprintf(buf + i, sz - i, " %u", tsk_peer_port(tsk));
3969 		conn_type = msg_nametype(&tsk->phdr);
3970 		conn_instance = msg_nameinst(&tsk->phdr);
3971 		i += scnprintf(buf + i, sz - i, " %u", conn_type);
3972 		i += scnprintf(buf + i, sz - i, " %u", conn_instance);
3973 	}
3974 	i += scnprintf(buf + i, sz - i, " | %u", tsk->published);
3975 	if (tsk->published) {
3976 		p = list_first_entry_or_null(&tsk->publications,
3977 					     struct publication, binding_sock);
3978 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.type : 0);
3979 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.lower : 0);
3980 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.upper : 0);
3981 	}
3982 	i += scnprintf(buf + i, sz - i, " | %u", tsk->snd_win);
3983 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_win);
3984 	i += scnprintf(buf + i, sz - i, " %u", tsk->max_pkt);
3985 	i += scnprintf(buf + i, sz - i, " %x", tsk->peer_caps);
3986 	i += scnprintf(buf + i, sz - i, " %u", tsk->cong_link_cnt);
3987 	i += scnprintf(buf + i, sz - i, " %u", tsk->snt_unacked);
3988 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_unacked);
3989 	i += scnprintf(buf + i, sz - i, " %u", atomic_read(&tsk->dupl_rcvcnt));
3990 	i += scnprintf(buf + i, sz - i, " %u", sk->sk_shutdown);
3991 	i += scnprintf(buf + i, sz - i, " | %d", sk_wmem_alloc_get(sk));
3992 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_sndbuf);
3993 	i += scnprintf(buf + i, sz - i, " | %d", sk_rmem_alloc_get(sk));
3994 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_rcvbuf);
3995 	i += scnprintf(buf + i, sz - i, " | %d\n", READ_ONCE(sk->sk_backlog.len));
3996 
3997 	if (dqueues & TIPC_DUMP_SK_SNDQ) {
3998 		i += scnprintf(buf + i, sz - i, "sk_write_queue: ");
3999 		i += tipc_list_dump(&sk->sk_write_queue, false, buf + i);
4000 	}
4001 
4002 	if (dqueues & TIPC_DUMP_SK_RCVQ) {
4003 		i += scnprintf(buf + i, sz - i, "sk_receive_queue: ");
4004 		i += tipc_list_dump(&sk->sk_receive_queue, false, buf + i);
4005 	}
4006 
4007 	if (dqueues & TIPC_DUMP_SK_BKLGQ) {
4008 		i += scnprintf(buf + i, sz - i, "sk_backlog:\n  head ");
4009 		i += tipc_skb_dump(sk->sk_backlog.head, false, buf + i);
4010 		if (sk->sk_backlog.tail != sk->sk_backlog.head) {
4011 			i += scnprintf(buf + i, sz - i, "  tail ");
4012 			i += tipc_skb_dump(sk->sk_backlog.tail, false,
4013 					   buf + i);
4014 		}
4015 	}
4016 
4017 	return i;
4018 }
4019