xref: /linux/net/tipc/socket.c (revision f1529936c0b65fb343f62f50e5313078719fc336)
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 <linux/uio.h>
41 #include <trace/events/sock.h>
42 
43 #include "core.h"
44 #include "name_table.h"
45 #include "node.h"
46 #include "link.h"
47 #include "name_distr.h"
48 #include "socket.h"
49 #include "bcast.h"
50 #include "netlink.h"
51 #include "group.h"
52 #include "trace.h"
53 
54 #define NAGLE_START_INIT	4
55 #define NAGLE_START_MAX		1024
56 #define CONN_TIMEOUT_DEFAULT    8000    /* default connect timeout = 8s */
57 #define CONN_PROBING_INTV	msecs_to_jiffies(3600000)  /* [ms] => 1 h */
58 #define TIPC_MAX_PORT		0xffffffff
59 #define TIPC_MIN_PORT		1
60 #define TIPC_ACK_RATE		4       /* ACK at 1/4 of rcv window size */
61 
62 enum {
63 	TIPC_LISTEN = TCP_LISTEN,
64 	TIPC_ESTABLISHED = TCP_ESTABLISHED,
65 	TIPC_OPEN = TCP_CLOSE,
66 	TIPC_DISCONNECTING = TCP_CLOSE_WAIT,
67 	TIPC_CONNECTING = TCP_SYN_SENT,
68 };
69 
70 struct sockaddr_pair {
71 	struct sockaddr_tipc sock;
72 	struct sockaddr_tipc member;
73 };
74 
75 /**
76  * struct tipc_sock - TIPC socket structure
77  * @sk: socket - interacts with 'port' and with user via the socket API
78  * @max_pkt: maximum packet size "hint" used when building messages sent by port
79  * @maxnagle: maximum size of msg which can be subject to nagle
80  * @portid: unique port identity in TIPC socket hash table
81  * @phdr: preformatted message header used when sending messages
82  * @cong_links: list of congested links
83  * @publications: list of publications for port
84  * @pub_count: total # of publications port has made during its lifetime
85  * @conn_timeout: the time we can wait for an unresponded setup request
86  * @probe_unacked: probe has not received ack yet
87  * @dupl_rcvcnt: number of bytes counted twice, in both backlog and rcv queue
88  * @cong_link_cnt: number of congested links
89  * @snt_unacked: # messages sent by socket, and not yet acked by peer
90  * @snd_win: send window size
91  * @peer_caps: peer capabilities mask
92  * @rcv_unacked: # messages read by user, but not yet acked back to peer
93  * @rcv_win: receive window size
94  * @peer: 'connected' peer for dgram/rdm
95  * @node: hash table node
96  * @mc_method: cookie for use between socket and broadcast layer
97  * @rcu: rcu struct for tipc_sock
98  * @group: TIPC communications group
99  * @oneway: message count in one direction (FIXME)
100  * @nagle_start: current nagle value
101  * @snd_backlog: send backlog count
102  * @msg_acc: messages accepted; used in managing backlog and nagle
103  * @pkt_cnt: TIPC socket packet count
104  * @expect_ack: whether this TIPC socket is expecting an ack
105  * @nodelay: setsockopt() TIPC_NODELAY setting
106  * @group_is_open: TIPC socket group is fully open (FIXME)
107  * @published: true if port has one or more associated names
108  * @conn_addrtype: address type used when establishing connection
109  */
110 struct tipc_sock {
111 	struct sock sk;
112 	u32 max_pkt;
113 	u32 maxnagle;
114 	u32 portid;
115 	struct tipc_msg phdr;
116 	struct list_head cong_links;
117 	struct list_head publications;
118 	u32 pub_count;
119 	atomic_t dupl_rcvcnt;
120 	u16 conn_timeout;
121 	bool probe_unacked;
122 	u16 cong_link_cnt;
123 	u16 snt_unacked;
124 	u16 snd_win;
125 	u16 peer_caps;
126 	u16 rcv_unacked;
127 	u16 rcv_win;
128 	struct sockaddr_tipc peer;
129 	struct rhash_head node;
130 	struct tipc_mc_method mc_method;
131 	struct rcu_head rcu;
132 	struct tipc_group *group;
133 	u32 oneway;
134 	u32 nagle_start;
135 	u16 snd_backlog;
136 	u16 msg_acc;
137 	u16 pkt_cnt;
138 	bool expect_ack;
139 	bool nodelay;
140 	bool group_is_open;
141 	bool published;
142 	u8 conn_addrtype;
143 };
144 
145 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
146 static void tipc_data_ready(struct sock *sk);
147 static void tipc_write_space(struct sock *sk);
148 static void tipc_sock_destruct(struct sock *sk);
149 static int tipc_release(struct socket *sock);
150 static void tipc_sk_timeout(struct timer_list *t);
151 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua);
152 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua);
153 static int tipc_sk_leave(struct tipc_sock *tsk);
154 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid);
155 static int tipc_sk_insert(struct tipc_sock *tsk);
156 static void tipc_sk_remove(struct tipc_sock *tsk);
157 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz);
158 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz);
159 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack);
160 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p);
161 
162 static const struct proto_ops packet_ops;
163 static const struct proto_ops stream_ops;
164 static const struct proto_ops msg_ops;
165 static struct proto tipc_proto;
166 static const struct rhashtable_params tsk_rht_params;
167 
168 static u32 tsk_own_node(struct tipc_sock *tsk)
169 {
170 	return msg_prevnode(&tsk->phdr);
171 }
172 
173 static u32 tsk_peer_node(struct tipc_sock *tsk)
174 {
175 	return msg_destnode(&tsk->phdr);
176 }
177 
178 static u32 tsk_peer_port(struct tipc_sock *tsk)
179 {
180 	return msg_destport(&tsk->phdr);
181 }
182 
183 static  bool tsk_unreliable(struct tipc_sock *tsk)
184 {
185 	return msg_src_droppable(&tsk->phdr) != 0;
186 }
187 
188 static void tsk_set_unreliable(struct tipc_sock *tsk, bool unreliable)
189 {
190 	msg_set_src_droppable(&tsk->phdr, unreliable ? 1 : 0);
191 }
192 
193 static bool tsk_unreturnable(struct tipc_sock *tsk)
194 {
195 	return msg_dest_droppable(&tsk->phdr) != 0;
196 }
197 
198 static void tsk_set_unreturnable(struct tipc_sock *tsk, bool unreturnable)
199 {
200 	msg_set_dest_droppable(&tsk->phdr, unreturnable ? 1 : 0);
201 }
202 
203 static int tsk_importance(struct tipc_sock *tsk)
204 {
205 	return msg_importance(&tsk->phdr);
206 }
207 
208 static struct tipc_sock *tipc_sk(const struct sock *sk)
209 {
210 	return container_of(sk, struct tipc_sock, sk);
211 }
212 
213 int tsk_set_importance(struct sock *sk, int imp)
214 {
215 	if (imp > TIPC_CRITICAL_IMPORTANCE)
216 		return -EINVAL;
217 	msg_set_importance(&tipc_sk(sk)->phdr, (u32)imp);
218 	return 0;
219 }
220 
221 static bool tsk_conn_cong(struct tipc_sock *tsk)
222 {
223 	return tsk->snt_unacked > tsk->snd_win;
224 }
225 
226 static u16 tsk_blocks(int len)
227 {
228 	return ((len / FLOWCTL_BLK_SZ) + 1);
229 }
230 
231 /* tsk_blocks(): translate a buffer size in bytes to number of
232  * advertisable blocks, taking into account the ratio truesize(len)/len
233  * We can trust that this ratio is always < 4 for len >= FLOWCTL_BLK_SZ
234  */
235 static u16 tsk_adv_blocks(int len)
236 {
237 	return len / FLOWCTL_BLK_SZ / 4;
238 }
239 
240 /* tsk_inc(): increment counter for sent or received data
241  * - If block based flow control is not supported by peer we
242  *   fall back to message based ditto, incrementing the counter
243  */
244 static u16 tsk_inc(struct tipc_sock *tsk, int msglen)
245 {
246 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
247 		return ((msglen / FLOWCTL_BLK_SZ) + 1);
248 	return 1;
249 }
250 
251 /* tsk_set_nagle - enable/disable nagle property by manipulating maxnagle
252  */
253 static void tsk_set_nagle(struct tipc_sock *tsk)
254 {
255 	struct sock *sk = &tsk->sk;
256 
257 	tsk->maxnagle = 0;
258 	if (sk->sk_type != SOCK_STREAM)
259 		return;
260 	if (tsk->nodelay)
261 		return;
262 	if (!(tsk->peer_caps & TIPC_NAGLE))
263 		return;
264 	/* Limit node local buffer size to avoid receive queue overflow */
265 	if (tsk->max_pkt == MAX_MSG_SIZE)
266 		tsk->maxnagle = 1500;
267 	else
268 		tsk->maxnagle = tsk->max_pkt;
269 }
270 
271 /**
272  * tsk_advance_rx_queue - discard first buffer in socket receive queue
273  * @sk: network socket
274  *
275  * Caller must hold socket lock
276  */
277 static void tsk_advance_rx_queue(struct sock *sk)
278 {
279 	trace_tipc_sk_advance_rx(sk, NULL, TIPC_DUMP_SK_RCVQ, " ");
280 	kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
281 }
282 
283 /* tipc_sk_respond() : send response message back to sender
284  */
285 static void tipc_sk_respond(struct sock *sk, struct sk_buff *skb, int err)
286 {
287 	u32 selector;
288 	u32 dnode;
289 	u32 onode = tipc_own_addr(sock_net(sk));
290 
291 	if (!tipc_msg_reverse(onode, &skb, err))
292 		return;
293 
294 	trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE, "@sk_respond!");
295 	dnode = msg_destnode(buf_msg(skb));
296 	selector = msg_origport(buf_msg(skb));
297 	tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector);
298 }
299 
300 /**
301  * tsk_rej_rx_queue - reject all buffers in socket receive queue
302  * @sk: network socket
303  * @error: response error code
304  *
305  * Caller must hold socket lock
306  */
307 static void tsk_rej_rx_queue(struct sock *sk, int error)
308 {
309 	struct sk_buff *skb;
310 
311 	while ((skb = __skb_dequeue(&sk->sk_receive_queue)))
312 		tipc_sk_respond(sk, skb, error);
313 }
314 
315 static bool tipc_sk_connected(const struct sock *sk)
316 {
317 	return READ_ONCE(sk->sk_state) == TIPC_ESTABLISHED;
318 }
319 
320 /* tipc_sk_type_connectionless - check if the socket is datagram socket
321  * @sk: socket
322  *
323  * Returns true if connection less, false otherwise
324  */
325 static bool tipc_sk_type_connectionless(struct sock *sk)
326 {
327 	return sk->sk_type == SOCK_RDM || sk->sk_type == SOCK_DGRAM;
328 }
329 
330 /* tsk_peer_msg - verify if message was sent by connected port's peer
331  *
332  * Handles cases where the node's network address has changed from
333  * the default of <0.0.0> to its configured setting.
334  */
335 static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg)
336 {
337 	struct sock *sk = &tsk->sk;
338 	u32 self = tipc_own_addr(sock_net(sk));
339 	u32 peer_port = tsk_peer_port(tsk);
340 	u32 orig_node, peer_node;
341 
342 	if (unlikely(!tipc_sk_connected(sk)))
343 		return false;
344 
345 	if (unlikely(msg_origport(msg) != peer_port))
346 		return false;
347 
348 	orig_node = msg_orignode(msg);
349 	peer_node = tsk_peer_node(tsk);
350 
351 	if (likely(orig_node == peer_node))
352 		return true;
353 
354 	if (!orig_node && peer_node == self)
355 		return true;
356 
357 	if (!peer_node && orig_node == self)
358 		return true;
359 
360 	return false;
361 }
362 
363 /* tipc_set_sk_state - set the sk_state of the socket
364  * @sk: socket
365  *
366  * Caller must hold socket lock
367  *
368  * Returns 0 on success, errno otherwise
369  */
370 static int tipc_set_sk_state(struct sock *sk, int state)
371 {
372 	int oldsk_state = sk->sk_state;
373 	int res = -EINVAL;
374 
375 	switch (state) {
376 	case TIPC_OPEN:
377 		res = 0;
378 		break;
379 	case TIPC_LISTEN:
380 	case TIPC_CONNECTING:
381 		if (oldsk_state == TIPC_OPEN)
382 			res = 0;
383 		break;
384 	case TIPC_ESTABLISHED:
385 		if (oldsk_state == TIPC_CONNECTING ||
386 		    oldsk_state == TIPC_OPEN)
387 			res = 0;
388 		break;
389 	case TIPC_DISCONNECTING:
390 		if (oldsk_state == TIPC_CONNECTING ||
391 		    oldsk_state == TIPC_ESTABLISHED)
392 			res = 0;
393 		break;
394 	}
395 
396 	if (!res)
397 		sk->sk_state = state;
398 
399 	return res;
400 }
401 
402 static int tipc_sk_sock_err(struct socket *sock, long *timeout)
403 {
404 	struct sock *sk = sock->sk;
405 	int err = sock_error(sk);
406 	int typ = sock->type;
407 
408 	if (err)
409 		return err;
410 	if (typ == SOCK_STREAM || typ == SOCK_SEQPACKET) {
411 		if (sk->sk_state == TIPC_DISCONNECTING)
412 			return -EPIPE;
413 		else if (!tipc_sk_connected(sk))
414 			return -ENOTCONN;
415 	}
416 	if (!*timeout)
417 		return -EAGAIN;
418 	if (signal_pending(current))
419 		return sock_intr_errno(*timeout);
420 
421 	return 0;
422 }
423 
424 #define tipc_wait_for_cond(sock_, timeo_, condition_)			       \
425 ({                                                                             \
426 	DEFINE_WAIT_FUNC(wait_, woken_wake_function);                          \
427 	struct sock *sk_;						       \
428 	int rc_;							       \
429 									       \
430 	while ((rc_ = !(condition_))) {					       \
431 		/* coupled with smp_wmb() in tipc_sk_proto_rcv() */            \
432 		smp_rmb();                                                     \
433 		sk_ = (sock_)->sk;					       \
434 		rc_ = tipc_sk_sock_err((sock_), timeo_);		       \
435 		if (rc_)						       \
436 			break;						       \
437 		add_wait_queue(sk_sleep(sk_), &wait_);                         \
438 		release_sock(sk_);					       \
439 		*(timeo_) = wait_woken(&wait_, TASK_INTERRUPTIBLE, *(timeo_)); \
440 		sched_annotate_sleep();				               \
441 		lock_sock(sk_);						       \
442 		remove_wait_queue(sk_sleep(sk_), &wait_);		       \
443 	}								       \
444 	rc_;								       \
445 })
446 
447 /**
448  * tipc_sk_create - create a TIPC socket
449  * @net: network namespace (must be default network)
450  * @sock: pre-allocated socket structure
451  * @protocol: protocol indicator (must be 0)
452  * @kern: caused by kernel or by userspace?
453  *
454  * This routine creates additional data structures used by the TIPC socket,
455  * initializes them, and links them together.
456  *
457  * Return: 0 on success, errno otherwise
458  */
459 static int tipc_sk_create(struct net *net, struct socket *sock,
460 			  int protocol, int kern)
461 {
462 	const struct proto_ops *ops;
463 	struct sock *sk;
464 	struct tipc_sock *tsk;
465 	struct tipc_msg *msg;
466 
467 	/* Validate arguments */
468 	if (unlikely(protocol != 0))
469 		return -EPROTONOSUPPORT;
470 
471 	switch (sock->type) {
472 	case SOCK_STREAM:
473 		ops = &stream_ops;
474 		break;
475 	case SOCK_SEQPACKET:
476 		ops = &packet_ops;
477 		break;
478 	case SOCK_DGRAM:
479 	case SOCK_RDM:
480 		ops = &msg_ops;
481 		break;
482 	default:
483 		return -EPROTOTYPE;
484 	}
485 
486 	/* Allocate socket's protocol area */
487 	sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto, kern);
488 	if (sk == NULL)
489 		return -ENOMEM;
490 
491 	tsk = tipc_sk(sk);
492 	tsk->max_pkt = MAX_PKT_DEFAULT;
493 	tsk->maxnagle = 0;
494 	tsk->nagle_start = NAGLE_START_INIT;
495 	INIT_LIST_HEAD(&tsk->publications);
496 	INIT_LIST_HEAD(&tsk->cong_links);
497 	msg = &tsk->phdr;
498 
499 	/* Finish initializing socket data structures */
500 	sock->ops = ops;
501 	sock_init_data(sock, sk);
502 	tipc_set_sk_state(sk, TIPC_OPEN);
503 	if (tipc_sk_insert(tsk)) {
504 		sk_free(sk);
505 		sock->sk = NULL;
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 disassociate 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_unsized *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, (struct sockaddr *)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_NONE, " ");
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 	LIST_HEAD(dsts);
1015 	int lookups = 0;
1016 	int dstcnt, rc;
1017 	bool cong;
1018 
1019 	ua->sa.type = msg_nametype(hdr);
1020 	ua->scope = msg_lookup_scope(hdr);
1021 
1022 	while (++lookups < 4) {
1023 		exclude = tipc_group_exclude(tsk->group);
1024 
1025 		first = NULL;
1026 
1027 		/* Look for a non-congested destination member, if any */
1028 		while (1) {
1029 			if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt,
1030 						       exclude, false))
1031 				return -EHOSTUNREACH;
1032 			tipc_dest_pop(&dsts, &node, &port);
1033 			cong = tipc_group_cong(tsk->group, node, port, blks,
1034 					       &mbr);
1035 			if (!cong)
1036 				break;
1037 			if (mbr == first)
1038 				break;
1039 			if (!first)
1040 				first = mbr;
1041 		}
1042 
1043 		/* Start over if destination was not in member list */
1044 		if (unlikely(!mbr))
1045 			continue;
1046 
1047 		if (likely(!cong && !tipc_dest_find(cong_links, node, 0)))
1048 			break;
1049 
1050 		/* Block or return if destination link or member is congested */
1051 		rc = tipc_wait_for_cond(sock, &timeout,
1052 					!tipc_dest_find(cong_links, node, 0) &&
1053 					tsk->group &&
1054 					!tipc_group_cong(tsk->group, node, port,
1055 							 blks, &mbr));
1056 		if (unlikely(rc))
1057 			return rc;
1058 
1059 		/* Send, unless destination disappeared while waiting */
1060 		if (likely(mbr))
1061 			break;
1062 	}
1063 
1064 	if (unlikely(lookups >= 4))
1065 		return -EHOSTUNREACH;
1066 
1067 	rc = tipc_send_group_msg(net, tsk, m, mbr, node, port, dlen);
1068 
1069 	return rc ? rc : dlen;
1070 }
1071 
1072 /**
1073  * tipc_send_group_bcast - send message to all members in communication group
1074  * @sock: socket structure
1075  * @m: message to send
1076  * @dlen: total length of message data
1077  * @timeout: timeout to wait for wakeup
1078  *
1079  * Called from function tipc_sendmsg(), which has done all sanity checks
1080  * Return: the number of bytes sent on success, or errno
1081  */
1082 static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
1083 				 int dlen, long timeout)
1084 {
1085 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1086 	struct sock *sk = sock->sk;
1087 	struct net *net = sock_net(sk);
1088 	struct tipc_sock *tsk = tipc_sk(sk);
1089 	struct tipc_nlist *dsts;
1090 	struct tipc_mc_method *method = &tsk->mc_method;
1091 	bool ack = method->mandatory && method->rcast;
1092 	int blks = tsk_blocks(MCAST_H_SIZE + dlen);
1093 	struct tipc_msg *hdr = &tsk->phdr;
1094 	int mtu = tipc_bcast_get_mtu(net);
1095 	struct sk_buff_head pkts;
1096 	int rc = -EHOSTUNREACH;
1097 
1098 	/* Block or return if any destination link or member is congested */
1099 	rc = tipc_wait_for_cond(sock, &timeout,
1100 				!tsk->cong_link_cnt && tsk->group &&
1101 				!tipc_group_bc_cong(tsk->group, blks));
1102 	if (unlikely(rc))
1103 		return rc;
1104 
1105 	dsts = tipc_group_dests(tsk->group);
1106 	if (!dsts->local && !dsts->remote)
1107 		return -EHOSTUNREACH;
1108 
1109 	/* Complete message header */
1110 	if (ua) {
1111 		msg_set_type(hdr, TIPC_GRP_MCAST_MSG);
1112 		msg_set_nameinst(hdr, ua->sa.instance);
1113 	} else {
1114 		msg_set_type(hdr, TIPC_GRP_BCAST_MSG);
1115 		msg_set_nameinst(hdr, 0);
1116 	}
1117 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
1118 	msg_set_destport(hdr, 0);
1119 	msg_set_destnode(hdr, 0);
1120 	msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(tsk->group));
1121 
1122 	/* Avoid getting stuck with repeated forced replicasts */
1123 	msg_set_grp_bc_ack_req(hdr, ack);
1124 
1125 	/* Build message as chain of buffers */
1126 	__skb_queue_head_init(&pkts);
1127 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1128 	if (unlikely(rc != dlen))
1129 		return rc;
1130 
1131 	/* Send message */
1132 	rc = tipc_mcast_xmit(net, &pkts, method, dsts, &tsk->cong_link_cnt);
1133 	if (unlikely(rc))
1134 		return rc;
1135 
1136 	/* Update broadcast sequence number and send windows */
1137 	tipc_group_update_bc_members(tsk->group, blks, ack);
1138 
1139 	/* Broadcast link is now free to choose method for next broadcast */
1140 	method->mandatory = false;
1141 	method->expires = jiffies;
1142 
1143 	return dlen;
1144 }
1145 
1146 /**
1147  * tipc_send_group_mcast - send message to all members with given identity
1148  * @sock: socket structure
1149  * @m: message to send
1150  * @dlen: total length of message data
1151  * @timeout: timeout to wait for wakeup
1152  *
1153  * Called from function tipc_sendmsg(), which has done all sanity checks
1154  * Return: the number of bytes sent on success, or errno
1155  */
1156 static int tipc_send_group_mcast(struct socket *sock, struct msghdr *m,
1157 				 int dlen, long timeout)
1158 {
1159 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1160 	struct sock *sk = sock->sk;
1161 	struct tipc_sock *tsk = tipc_sk(sk);
1162 	struct tipc_group *grp = tsk->group;
1163 	struct tipc_msg *hdr = &tsk->phdr;
1164 	struct net *net = sock_net(sk);
1165 	u32 dstcnt, exclude;
1166 	LIST_HEAD(dsts);
1167 
1168 	ua->sa.type = msg_nametype(hdr);
1169 	ua->scope = msg_lookup_scope(hdr);
1170 	exclude = tipc_group_exclude(grp);
1171 
1172 	if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt, exclude, true))
1173 		return -EHOSTUNREACH;
1174 
1175 	if (dstcnt == 1) {
1176 		tipc_dest_pop(&dsts, &ua->sk.node, &ua->sk.ref);
1177 		return tipc_send_group_unicast(sock, m, dlen, timeout);
1178 	}
1179 
1180 	tipc_dest_list_purge(&dsts);
1181 	return tipc_send_group_bcast(sock, m, dlen, timeout);
1182 }
1183 
1184 /**
1185  * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets
1186  * @net: the associated network namespace
1187  * @arrvq: queue with arriving messages, to be cloned after destination lookup
1188  * @inputq: queue with cloned messages, delivered to socket after dest lookup
1189  *
1190  * Multi-threaded: parallel calls with reference to same queues may occur
1191  */
1192 void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
1193 		       struct sk_buff_head *inputq)
1194 {
1195 	u32 self = tipc_own_addr(net);
1196 	struct sk_buff *skb, *_skb;
1197 	u32 portid, onode;
1198 	struct sk_buff_head tmpq;
1199 	struct list_head dports;
1200 	struct tipc_msg *hdr;
1201 	struct tipc_uaddr ua;
1202 	int user, mtyp, hlen;
1203 
1204 	__skb_queue_head_init(&tmpq);
1205 	INIT_LIST_HEAD(&dports);
1206 	ua.addrtype = TIPC_SERVICE_RANGE;
1207 
1208 	/* tipc_skb_peek() increments the head skb's reference counter */
1209 	skb = tipc_skb_peek(arrvq, &inputq->lock);
1210 	for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) {
1211 		hdr = buf_msg(skb);
1212 		user = msg_user(hdr);
1213 		mtyp = msg_type(hdr);
1214 		hlen = skb_headroom(skb) + msg_hdr_sz(hdr);
1215 		onode = msg_orignode(hdr);
1216 		ua.sr.type = msg_nametype(hdr);
1217 		ua.sr.lower = msg_namelower(hdr);
1218 		ua.sr.upper = msg_nameupper(hdr);
1219 		if (onode == self)
1220 			ua.scope = TIPC_ANY_SCOPE;
1221 		else
1222 			ua.scope = TIPC_CLUSTER_SCOPE;
1223 
1224 		if (mtyp == TIPC_GRP_UCAST_MSG || user == GROUP_PROTOCOL) {
1225 			spin_lock_bh(&inputq->lock);
1226 			if (skb_peek(arrvq) == skb) {
1227 				__skb_dequeue(arrvq);
1228 				__skb_queue_tail(inputq, skb);
1229 			}
1230 			kfree_skb(skb);
1231 			spin_unlock_bh(&inputq->lock);
1232 			continue;
1233 		}
1234 
1235 		/* Group messages require exact scope match */
1236 		if (msg_in_group(hdr)) {
1237 			ua.sr.lower = 0;
1238 			ua.sr.upper = ~0;
1239 			ua.scope = msg_lookup_scope(hdr);
1240 		}
1241 
1242 		/* Create destination port list: */
1243 		tipc_nametbl_lookup_mcast_sockets(net, &ua, &dports);
1244 
1245 		/* Clone message per destination */
1246 		while (tipc_dest_pop(&dports, NULL, &portid)) {
1247 			_skb = __pskb_copy(skb, hlen, GFP_ATOMIC);
1248 			if (_skb) {
1249 				msg_set_destport(buf_msg(_skb), portid);
1250 				__skb_queue_tail(&tmpq, _skb);
1251 				continue;
1252 			}
1253 			pr_warn("Failed to clone mcast rcv buffer\n");
1254 		}
1255 		/* Append clones to inputq only if skb is still head of arrvq */
1256 		spin_lock_bh(&inputq->lock);
1257 		if (skb_peek(arrvq) == skb) {
1258 			skb_queue_splice_tail_init(&tmpq, inputq);
1259 			/* Decrement the skb's refcnt */
1260 			kfree_skb(__skb_dequeue(arrvq));
1261 		}
1262 		spin_unlock_bh(&inputq->lock);
1263 		__skb_queue_purge(&tmpq);
1264 		kfree_skb(skb);
1265 	}
1266 	tipc_sk_rcv(net, inputq);
1267 }
1268 
1269 /* tipc_sk_push_backlog(): send accumulated buffers in socket write queue
1270  *                         when socket is in Nagle mode
1271  */
1272 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack)
1273 {
1274 	struct sk_buff_head *txq = &tsk->sk.sk_write_queue;
1275 	struct sk_buff *skb = skb_peek_tail(txq);
1276 	struct net *net = sock_net(&tsk->sk);
1277 	u32 dnode = tsk_peer_node(tsk);
1278 	int rc;
1279 
1280 	if (nagle_ack) {
1281 		tsk->pkt_cnt += skb_queue_len(txq);
1282 		if (!tsk->pkt_cnt || tsk->msg_acc / tsk->pkt_cnt < 2) {
1283 			tsk->oneway = 0;
1284 			if (tsk->nagle_start < NAGLE_START_MAX)
1285 				tsk->nagle_start *= 2;
1286 			tsk->expect_ack = false;
1287 			pr_debug("tsk %10u: bad nagle %u -> %u, next start %u!\n",
1288 				 tsk->portid, tsk->msg_acc, tsk->pkt_cnt,
1289 				 tsk->nagle_start);
1290 		} else {
1291 			tsk->nagle_start = NAGLE_START_INIT;
1292 			if (skb) {
1293 				msg_set_ack_required(buf_msg(skb));
1294 				tsk->expect_ack = true;
1295 			} else {
1296 				tsk->expect_ack = false;
1297 			}
1298 		}
1299 		tsk->msg_acc = 0;
1300 		tsk->pkt_cnt = 0;
1301 	}
1302 
1303 	if (!skb || tsk->cong_link_cnt)
1304 		return;
1305 
1306 	/* Do not send SYN again after congestion */
1307 	if (msg_is_syn(buf_msg(skb)))
1308 		return;
1309 
1310 	if (tsk->msg_acc)
1311 		tsk->pkt_cnt += skb_queue_len(txq);
1312 	tsk->snt_unacked += tsk->snd_backlog;
1313 	tsk->snd_backlog = 0;
1314 	rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1315 	if (rc == -ELINKCONG)
1316 		tsk->cong_link_cnt = 1;
1317 }
1318 
1319 /**
1320  * tipc_sk_conn_proto_rcv - receive a connection mng protocol message
1321  * @tsk: receiving socket
1322  * @skb: pointer to message buffer.
1323  * @inputq: buffer list containing the buffers
1324  * @xmitq: output message area
1325  */
1326 static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb,
1327 				   struct sk_buff_head *inputq,
1328 				   struct sk_buff_head *xmitq)
1329 {
1330 	struct tipc_msg *hdr = buf_msg(skb);
1331 	u32 onode = tsk_own_node(tsk);
1332 	struct sock *sk = &tsk->sk;
1333 	int mtyp = msg_type(hdr);
1334 	bool was_cong;
1335 
1336 	/* Ignore if connection cannot be validated: */
1337 	if (!tsk_peer_msg(tsk, hdr)) {
1338 		trace_tipc_sk_drop_msg(sk, skb, TIPC_DUMP_NONE, "@proto_rcv!");
1339 		goto exit;
1340 	}
1341 
1342 	if (unlikely(msg_errcode(hdr))) {
1343 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1344 		tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
1345 				      tsk_peer_port(tsk));
1346 		sk->sk_state_change(sk);
1347 
1348 		/* State change is ignored if socket already awake,
1349 		 * - convert msg to abort msg and add to inqueue
1350 		 */
1351 		msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE);
1352 		msg_set_type(hdr, TIPC_CONN_MSG);
1353 		msg_set_size(hdr, BASIC_H_SIZE);
1354 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1355 		__skb_queue_tail(inputq, skb);
1356 		return;
1357 	}
1358 
1359 	tsk->probe_unacked = false;
1360 
1361 	if (mtyp == CONN_PROBE) {
1362 		msg_set_type(hdr, CONN_PROBE_REPLY);
1363 		if (tipc_msg_reverse(onode, &skb, TIPC_OK))
1364 			__skb_queue_tail(xmitq, skb);
1365 		return;
1366 	} else if (mtyp == CONN_ACK) {
1367 		if (tsk->snt_unacked < msg_conn_ack(hdr))
1368 			goto exit;
1369 
1370 		was_cong = tsk_conn_cong(tsk);
1371 		tipc_sk_push_backlog(tsk, msg_nagle_ack(hdr));
1372 		tsk->snt_unacked -= msg_conn_ack(hdr);
1373 		if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1374 			tsk->snd_win = msg_adv_win(hdr);
1375 		if (was_cong && !tsk_conn_cong(tsk))
1376 			sk->sk_write_space(sk);
1377 	} else if (mtyp != CONN_PROBE_REPLY) {
1378 		pr_warn("Received unknown CONN_PROTO msg\n");
1379 	}
1380 exit:
1381 	kfree_skb(skb);
1382 }
1383 
1384 /**
1385  * tipc_sendmsg - send message in connectionless manner
1386  * @sock: socket structure
1387  * @m: message to send
1388  * @dsz: amount of user data to be sent
1389  *
1390  * Message must have an destination specified explicitly.
1391  * Used for SOCK_RDM and SOCK_DGRAM messages,
1392  * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
1393  * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
1394  *
1395  * Return: the number of bytes sent on success, or errno otherwise
1396  */
1397 static int tipc_sendmsg(struct socket *sock,
1398 			struct msghdr *m, size_t dsz)
1399 {
1400 	struct sock *sk = sock->sk;
1401 	int ret;
1402 
1403 	lock_sock(sk);
1404 	ret = __tipc_sendmsg(sock, m, dsz);
1405 	release_sock(sk);
1406 
1407 	return ret;
1408 }
1409 
1410 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
1411 {
1412 	struct sock *sk = sock->sk;
1413 	struct net *net = sock_net(sk);
1414 	struct tipc_sock *tsk = tipc_sk(sk);
1415 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1416 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1417 	struct list_head *clinks = &tsk->cong_links;
1418 	bool syn = !tipc_sk_type_connectionless(sk);
1419 	struct tipc_group *grp = tsk->group;
1420 	struct tipc_msg *hdr = &tsk->phdr;
1421 	struct tipc_socket_addr skaddr;
1422 	struct sk_buff_head pkts;
1423 	int atype, mtu, rc;
1424 
1425 	if (unlikely(dlen > TIPC_MAX_USER_MSG_SIZE))
1426 		return -EMSGSIZE;
1427 
1428 	if (ua) {
1429 		if (!tipc_uaddr_valid(ua, m->msg_namelen))
1430 			return -EINVAL;
1431 		atype = ua->addrtype;
1432 	}
1433 
1434 	/* If socket belongs to a communication group follow other paths */
1435 	if (grp) {
1436 		if (!ua)
1437 			return tipc_send_group_bcast(sock, m, dlen, timeout);
1438 		if (atype == TIPC_SERVICE_ADDR)
1439 			return tipc_send_group_anycast(sock, m, dlen, timeout);
1440 		if (atype == TIPC_SOCKET_ADDR)
1441 			return tipc_send_group_unicast(sock, m, dlen, timeout);
1442 		if (atype == TIPC_SERVICE_RANGE)
1443 			return tipc_send_group_mcast(sock, m, dlen, timeout);
1444 		return -EINVAL;
1445 	}
1446 
1447 	if (!ua) {
1448 		ua = (struct tipc_uaddr *)&tsk->peer;
1449 		if (!syn && ua->family != AF_TIPC)
1450 			return -EDESTADDRREQ;
1451 		atype = ua->addrtype;
1452 	}
1453 
1454 	if (unlikely(syn)) {
1455 		if (sk->sk_state == TIPC_LISTEN)
1456 			return -EPIPE;
1457 		if (sk->sk_state != TIPC_OPEN)
1458 			return -EISCONN;
1459 		if (tsk->published)
1460 			return -EOPNOTSUPP;
1461 		if (atype == TIPC_SERVICE_ADDR)
1462 			tsk->conn_addrtype = atype;
1463 		msg_set_syn(hdr, 1);
1464 	}
1465 
1466 	memset(&skaddr, 0, sizeof(skaddr));
1467 
1468 	/* Determine destination */
1469 	if (atype == TIPC_SERVICE_RANGE) {
1470 		return tipc_sendmcast(sock, ua, m, dlen, timeout);
1471 	} else if (atype == TIPC_SERVICE_ADDR) {
1472 		skaddr.node = ua->lookup_node;
1473 		ua->scope = tipc_node2scope(skaddr.node);
1474 		if (!tipc_nametbl_lookup_anycast(net, ua, &skaddr))
1475 			return -EHOSTUNREACH;
1476 	} else if (atype == TIPC_SOCKET_ADDR) {
1477 		skaddr = ua->sk;
1478 	} else {
1479 		return -EINVAL;
1480 	}
1481 
1482 	/* Block or return if destination link is congested */
1483 	rc = tipc_wait_for_cond(sock, &timeout,
1484 				!tipc_dest_find(clinks, skaddr.node, 0));
1485 	if (unlikely(rc))
1486 		return rc;
1487 
1488 	/* Finally build message header */
1489 	msg_set_destnode(hdr, skaddr.node);
1490 	msg_set_destport(hdr, skaddr.ref);
1491 	if (atype == TIPC_SERVICE_ADDR) {
1492 		msg_set_type(hdr, TIPC_NAMED_MSG);
1493 		msg_set_hdr_sz(hdr, NAMED_H_SIZE);
1494 		msg_set_nametype(hdr, ua->sa.type);
1495 		msg_set_nameinst(hdr, ua->sa.instance);
1496 		msg_set_lookup_scope(hdr, ua->scope);
1497 	} else { /* TIPC_SOCKET_ADDR */
1498 		msg_set_type(hdr, TIPC_DIRECT_MSG);
1499 		msg_set_lookup_scope(hdr, 0);
1500 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1501 	}
1502 
1503 	/* Add message body */
1504 	__skb_queue_head_init(&pkts);
1505 	mtu = tipc_node_get_mtu(net, skaddr.node, tsk->portid, true);
1506 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1507 	if (unlikely(rc != dlen))
1508 		return rc;
1509 	if (unlikely(syn && !tipc_msg_skb_clone(&pkts, &sk->sk_write_queue))) {
1510 		__skb_queue_purge(&pkts);
1511 		return -ENOMEM;
1512 	}
1513 
1514 	/* Send message */
1515 	trace_tipc_sk_sendmsg(sk, skb_peek(&pkts), TIPC_DUMP_SK_SNDQ, " ");
1516 	rc = tipc_node_xmit(net, &pkts, skaddr.node, tsk->portid);
1517 	if (unlikely(rc == -ELINKCONG)) {
1518 		tipc_dest_push(clinks, skaddr.node, 0);
1519 		tsk->cong_link_cnt++;
1520 		rc = 0;
1521 	}
1522 
1523 	if (unlikely(syn && !rc)) {
1524 		tipc_set_sk_state(sk, TIPC_CONNECTING);
1525 		if (dlen && timeout) {
1526 			timeout = msecs_to_jiffies(timeout);
1527 			tipc_wait_for_connect(sock, &timeout);
1528 		}
1529 	}
1530 
1531 	return rc ? rc : dlen;
1532 }
1533 
1534 /**
1535  * tipc_sendstream - send stream-oriented data
1536  * @sock: socket structure
1537  * @m: data to send
1538  * @dsz: total length of data to be transmitted
1539  *
1540  * Used for SOCK_STREAM data.
1541  *
1542  * Return: the number of bytes sent on success (or partial success),
1543  * or errno if no data sent
1544  */
1545 static int tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz)
1546 {
1547 	struct sock *sk = sock->sk;
1548 	int ret;
1549 
1550 	lock_sock(sk);
1551 	ret = __tipc_sendstream(sock, m, dsz);
1552 	release_sock(sk);
1553 
1554 	return ret;
1555 }
1556 
1557 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dlen)
1558 {
1559 	struct sock *sk = sock->sk;
1560 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1561 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1562 	struct sk_buff_head *txq = &sk->sk_write_queue;
1563 	struct tipc_sock *tsk = tipc_sk(sk);
1564 	struct tipc_msg *hdr = &tsk->phdr;
1565 	struct net *net = sock_net(sk);
1566 	struct sk_buff *skb;
1567 	u32 dnode = tsk_peer_node(tsk);
1568 	int maxnagle = tsk->maxnagle;
1569 	int maxpkt = tsk->max_pkt;
1570 	int send, sent = 0;
1571 	int blocks, rc = 0;
1572 
1573 	if (unlikely(dlen > INT_MAX))
1574 		return -EMSGSIZE;
1575 
1576 	/* Handle implicit connection setup */
1577 	if (unlikely(dest && sk->sk_state == TIPC_OPEN)) {
1578 		rc = __tipc_sendmsg(sock, m, dlen);
1579 		if (dlen && dlen == rc) {
1580 			tsk->peer_caps = tipc_node_get_capabilities(net, dnode);
1581 			tsk->snt_unacked = tsk_inc(tsk, dlen + msg_hdr_sz(hdr));
1582 		}
1583 		return rc;
1584 	}
1585 
1586 	do {
1587 		rc = tipc_wait_for_cond(sock, &timeout,
1588 					(!tsk->cong_link_cnt &&
1589 					 !tsk_conn_cong(tsk) &&
1590 					 tipc_sk_connected(sk)));
1591 		if (unlikely(rc))
1592 			break;
1593 		send = min_t(size_t, dlen - sent, TIPC_MAX_USER_MSG_SIZE);
1594 		blocks = tsk->snd_backlog;
1595 		if (tsk->oneway++ >= tsk->nagle_start && maxnagle &&
1596 		    send <= maxnagle) {
1597 			rc = tipc_msg_append(hdr, m, send, maxnagle, txq);
1598 			if (unlikely(rc < 0))
1599 				break;
1600 			blocks += rc;
1601 			tsk->msg_acc++;
1602 			if (blocks <= 64 && tsk->expect_ack) {
1603 				tsk->snd_backlog = blocks;
1604 				sent += send;
1605 				break;
1606 			} else if (blocks > 64) {
1607 				tsk->pkt_cnt += skb_queue_len(txq);
1608 			} else {
1609 				skb = skb_peek_tail(txq);
1610 				if (skb) {
1611 					msg_set_ack_required(buf_msg(skb));
1612 					tsk->expect_ack = true;
1613 				} else {
1614 					tsk->expect_ack = false;
1615 				}
1616 				tsk->msg_acc = 0;
1617 				tsk->pkt_cnt = 0;
1618 			}
1619 		} else {
1620 			rc = tipc_msg_build(hdr, m, sent, send, maxpkt, txq);
1621 			if (unlikely(rc != send))
1622 				break;
1623 			blocks += tsk_inc(tsk, send + MIN_H_SIZE);
1624 		}
1625 		trace_tipc_sk_sendstream(sk, skb_peek(txq),
1626 					 TIPC_DUMP_SK_SNDQ, " ");
1627 		rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1628 		if (unlikely(rc == -ELINKCONG)) {
1629 			tsk->cong_link_cnt = 1;
1630 			rc = 0;
1631 		}
1632 		if (likely(!rc)) {
1633 			tsk->snt_unacked += blocks;
1634 			tsk->snd_backlog = 0;
1635 			sent += send;
1636 		}
1637 	} while (sent < dlen && !rc);
1638 
1639 	return sent ? sent : rc;
1640 }
1641 
1642 /**
1643  * tipc_send_packet - send a connection-oriented message
1644  * @sock: socket structure
1645  * @m: message to send
1646  * @dsz: length of data to be transmitted
1647  *
1648  * Used for SOCK_SEQPACKET messages.
1649  *
1650  * Return: the number of bytes sent on success, or errno otherwise
1651  */
1652 static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz)
1653 {
1654 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
1655 		return -EMSGSIZE;
1656 
1657 	return tipc_sendstream(sock, m, dsz);
1658 }
1659 
1660 /* tipc_sk_finish_conn - complete the setup of a connection
1661  */
1662 static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port,
1663 				u32 peer_node)
1664 {
1665 	struct sock *sk = &tsk->sk;
1666 	struct net *net = sock_net(sk);
1667 	struct tipc_msg *msg = &tsk->phdr;
1668 
1669 	msg_set_syn(msg, 0);
1670 	msg_set_destnode(msg, peer_node);
1671 	msg_set_destport(msg, peer_port);
1672 	msg_set_type(msg, TIPC_CONN_MSG);
1673 	msg_set_lookup_scope(msg, 0);
1674 	msg_set_hdr_sz(msg, SHORT_H_SIZE);
1675 
1676 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
1677 	tipc_set_sk_state(sk, TIPC_ESTABLISHED);
1678 	tipc_node_add_conn(net, peer_node, tsk->portid, peer_port);
1679 	tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid, true);
1680 	tsk->peer_caps = tipc_node_get_capabilities(net, peer_node);
1681 	tsk_set_nagle(tsk);
1682 	__skb_queue_purge(&sk->sk_write_queue);
1683 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1684 		return;
1685 
1686 	/* Fall back to message based flow control */
1687 	tsk->rcv_win = FLOWCTL_MSG_WIN;
1688 	tsk->snd_win = FLOWCTL_MSG_WIN;
1689 }
1690 
1691 /**
1692  * tipc_sk_set_orig_addr - capture sender's address for received message
1693  * @m: descriptor for message info
1694  * @skb: received message
1695  *
1696  * Note: Address is not captured if not requested by receiver.
1697  */
1698 static void tipc_sk_set_orig_addr(struct msghdr *m, struct sk_buff *skb)
1699 {
1700 	DECLARE_SOCKADDR(struct sockaddr_pair *, srcaddr, m->msg_name);
1701 	struct tipc_msg *hdr = buf_msg(skb);
1702 
1703 	if (!srcaddr)
1704 		return;
1705 
1706 	srcaddr->sock.family = AF_TIPC;
1707 	srcaddr->sock.addrtype = TIPC_SOCKET_ADDR;
1708 	srcaddr->sock.scope = 0;
1709 	srcaddr->sock.addr.id.ref = msg_origport(hdr);
1710 	srcaddr->sock.addr.id.node = msg_orignode(hdr);
1711 	srcaddr->sock.addr.name.domain = 0;
1712 	m->msg_namelen = sizeof(struct sockaddr_tipc);
1713 
1714 	if (!msg_in_group(hdr))
1715 		return;
1716 
1717 	/* Group message users may also want to know sending member's id */
1718 	srcaddr->member.family = AF_TIPC;
1719 	srcaddr->member.addrtype = TIPC_SERVICE_ADDR;
1720 	srcaddr->member.scope = 0;
1721 	srcaddr->member.addr.name.name.type = msg_nametype(hdr);
1722 	srcaddr->member.addr.name.name.instance = TIPC_SKB_CB(skb)->orig_member;
1723 	srcaddr->member.addr.name.domain = 0;
1724 	m->msg_namelen = sizeof(*srcaddr);
1725 }
1726 
1727 /**
1728  * tipc_sk_anc_data_recv - optionally capture ancillary data for received message
1729  * @m: descriptor for message info
1730  * @skb: received message buffer
1731  * @tsk: TIPC port associated with message
1732  *
1733  * Note: Ancillary data is not captured if not requested by receiver.
1734  *
1735  * Return: 0 if successful, otherwise errno
1736  */
1737 static int tipc_sk_anc_data_recv(struct msghdr *m, struct sk_buff *skb,
1738 				 struct tipc_sock *tsk)
1739 {
1740 	struct tipc_msg *hdr;
1741 	u32 data[3] = {0,};
1742 	bool has_addr;
1743 	int dlen, rc;
1744 
1745 	if (likely(m->msg_controllen == 0))
1746 		return 0;
1747 
1748 	hdr = buf_msg(skb);
1749 	dlen = msg_data_sz(hdr);
1750 
1751 	/* Capture errored message object, if any */
1752 	if (msg_errcode(hdr)) {
1753 		if (skb_linearize(skb))
1754 			return -ENOMEM;
1755 		hdr = buf_msg(skb);
1756 		data[0] = msg_errcode(hdr);
1757 		data[1] = dlen;
1758 		rc = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, data);
1759 		if (rc || !dlen)
1760 			return rc;
1761 		rc = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, dlen, msg_data(hdr));
1762 		if (rc)
1763 			return rc;
1764 	}
1765 
1766 	/* Capture TIPC_SERVICE_ADDR/RANGE destination address, if any */
1767 	switch (msg_type(hdr)) {
1768 	case TIPC_NAMED_MSG:
1769 		has_addr = true;
1770 		data[0] = msg_nametype(hdr);
1771 		data[1] = msg_namelower(hdr);
1772 		data[2] = data[1];
1773 		break;
1774 	case TIPC_MCAST_MSG:
1775 		has_addr = true;
1776 		data[0] = msg_nametype(hdr);
1777 		data[1] = msg_namelower(hdr);
1778 		data[2] = msg_nameupper(hdr);
1779 		break;
1780 	case TIPC_CONN_MSG:
1781 		has_addr = !!tsk->conn_addrtype;
1782 		data[0] = msg_nametype(&tsk->phdr);
1783 		data[1] = msg_nameinst(&tsk->phdr);
1784 		data[2] = data[1];
1785 		break;
1786 	default:
1787 		has_addr = false;
1788 	}
1789 	if (!has_addr)
1790 		return 0;
1791 	return put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, data);
1792 }
1793 
1794 static struct sk_buff *tipc_sk_build_ack(struct tipc_sock *tsk)
1795 {
1796 	struct sock *sk = &tsk->sk;
1797 	struct sk_buff *skb = NULL;
1798 	struct tipc_msg *msg;
1799 	u32 peer_port = tsk_peer_port(tsk);
1800 	u32 dnode = tsk_peer_node(tsk);
1801 
1802 	if (!tipc_sk_connected(sk))
1803 		return NULL;
1804 	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
1805 			      dnode, tsk_own_node(tsk), peer_port,
1806 			      tsk->portid, TIPC_OK);
1807 	if (!skb)
1808 		return NULL;
1809 	msg = buf_msg(skb);
1810 	msg_set_conn_ack(msg, tsk->rcv_unacked);
1811 	tsk->rcv_unacked = 0;
1812 
1813 	/* Adjust to and advertize the correct window limit */
1814 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) {
1815 		tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf);
1816 		msg_set_adv_win(msg, tsk->rcv_win);
1817 	}
1818 	return skb;
1819 }
1820 
1821 static void tipc_sk_send_ack(struct tipc_sock *tsk)
1822 {
1823 	struct sk_buff *skb;
1824 
1825 	skb = tipc_sk_build_ack(tsk);
1826 	if (!skb)
1827 		return;
1828 
1829 	tipc_node_xmit_skb(sock_net(&tsk->sk), skb, tsk_peer_node(tsk),
1830 			   msg_link_selector(buf_msg(skb)));
1831 }
1832 
1833 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
1834 {
1835 	struct sock *sk = sock->sk;
1836 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1837 	long timeo = *timeop;
1838 	int err = sock_error(sk);
1839 
1840 	if (err)
1841 		return err;
1842 
1843 	for (;;) {
1844 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1845 			if (sk->sk_shutdown & RCV_SHUTDOWN) {
1846 				err = -ENOTCONN;
1847 				break;
1848 			}
1849 			add_wait_queue(sk_sleep(sk), &wait);
1850 			release_sock(sk);
1851 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
1852 			sched_annotate_sleep();
1853 			lock_sock(sk);
1854 			remove_wait_queue(sk_sleep(sk), &wait);
1855 		}
1856 		err = 0;
1857 		if (!skb_queue_empty(&sk->sk_receive_queue))
1858 			break;
1859 		err = -EAGAIN;
1860 		if (!timeo)
1861 			break;
1862 		err = sock_intr_errno(timeo);
1863 		if (signal_pending(current))
1864 			break;
1865 
1866 		err = sock_error(sk);
1867 		if (err)
1868 			break;
1869 	}
1870 	*timeop = timeo;
1871 	return err;
1872 }
1873 
1874 /**
1875  * tipc_recvmsg - receive packet-oriented message
1876  * @sock: network socket
1877  * @m: descriptor for message info
1878  * @buflen: length of user buffer area
1879  * @flags: receive flags
1880  *
1881  * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1882  * If the complete message doesn't fit in user area, truncate it.
1883  *
1884  * Return: size of returned message data, errno otherwise
1885  */
1886 static int tipc_recvmsg(struct socket *sock, struct msghdr *m,
1887 			size_t buflen,	int flags)
1888 {
1889 	struct sock *sk = sock->sk;
1890 	bool connected = !tipc_sk_type_connectionless(sk);
1891 	struct tipc_sock *tsk = tipc_sk(sk);
1892 	int rc, err, hlen, dlen, copy;
1893 	struct tipc_skb_cb *skb_cb;
1894 	struct sk_buff_head xmitq;
1895 	struct tipc_msg *hdr;
1896 	struct sk_buff *skb;
1897 	bool grp_evt;
1898 	long timeout;
1899 
1900 	/* Catch invalid receive requests */
1901 	if (unlikely(!buflen))
1902 		return -EINVAL;
1903 
1904 	lock_sock(sk);
1905 	if (unlikely(connected && sk->sk_state == TIPC_OPEN)) {
1906 		rc = -ENOTCONN;
1907 		goto exit;
1908 	}
1909 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1910 
1911 	/* Step rcv queue to first msg with data or error; wait if necessary */
1912 	do {
1913 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
1914 		if (unlikely(rc))
1915 			goto exit;
1916 		skb = skb_peek(&sk->sk_receive_queue);
1917 		skb_cb = TIPC_SKB_CB(skb);
1918 		hdr = buf_msg(skb);
1919 		dlen = msg_data_sz(hdr);
1920 		hlen = msg_hdr_sz(hdr);
1921 		err = msg_errcode(hdr);
1922 		grp_evt = msg_is_grp_evt(hdr);
1923 		if (likely(dlen || err))
1924 			break;
1925 		tsk_advance_rx_queue(sk);
1926 	} while (1);
1927 
1928 	/* Collect msg meta data, including error code and rejected data */
1929 	tipc_sk_set_orig_addr(m, skb);
1930 	rc = tipc_sk_anc_data_recv(m, skb, tsk);
1931 	if (unlikely(rc))
1932 		goto exit;
1933 	hdr = buf_msg(skb);
1934 
1935 	/* Capture data if non-error msg, otherwise just set return value */
1936 	if (likely(!err)) {
1937 		int offset = skb_cb->bytes_read;
1938 
1939 		copy = min_t(size_t, dlen - offset, buflen);
1940 		rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
1941 		if (unlikely(rc))
1942 			goto exit;
1943 		if (unlikely(offset + copy < dlen)) {
1944 			if (flags & MSG_EOR) {
1945 				if (!(flags & MSG_PEEK))
1946 					skb_cb->bytes_read = offset + copy;
1947 			} else {
1948 				m->msg_flags |= MSG_TRUNC;
1949 				skb_cb->bytes_read = 0;
1950 			}
1951 		} else {
1952 			if (flags & MSG_EOR)
1953 				m->msg_flags |= MSG_EOR;
1954 			skb_cb->bytes_read = 0;
1955 		}
1956 	} else {
1957 		copy = 0;
1958 		rc = 0;
1959 		if (err != TIPC_CONN_SHUTDOWN && connected && !m->msg_control) {
1960 			rc = -ECONNRESET;
1961 			goto exit;
1962 		}
1963 	}
1964 
1965 	/* Mark message as group event if applicable */
1966 	if (unlikely(grp_evt)) {
1967 		if (msg_grp_evt(hdr) == TIPC_WITHDRAWN)
1968 			m->msg_flags |= MSG_EOR;
1969 		m->msg_flags |= MSG_OOB;
1970 		copy = 0;
1971 	}
1972 
1973 	/* Caption of data or error code/rejected data was successful */
1974 	if (unlikely(flags & MSG_PEEK))
1975 		goto exit;
1976 
1977 	/* Send group flow control advertisement when applicable */
1978 	if (tsk->group && msg_in_group(hdr) && !grp_evt) {
1979 		__skb_queue_head_init(&xmitq);
1980 		tipc_group_update_rcv_win(tsk->group, tsk_blocks(hlen + dlen),
1981 					  msg_orignode(hdr), msg_origport(hdr),
1982 					  &xmitq);
1983 		tipc_node_distr_xmit(sock_net(sk), &xmitq);
1984 	}
1985 
1986 	if (skb_cb->bytes_read)
1987 		goto exit;
1988 
1989 	tsk_advance_rx_queue(sk);
1990 
1991 	if (likely(!connected))
1992 		goto exit;
1993 
1994 	/* Send connection flow control advertisement when applicable */
1995 	tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
1996 	if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
1997 		tipc_sk_send_ack(tsk);
1998 exit:
1999 	release_sock(sk);
2000 	return rc ? rc : copy;
2001 }
2002 
2003 /**
2004  * tipc_recvstream - receive stream-oriented data
2005  * @sock: network socket
2006  * @m: descriptor for message info
2007  * @buflen: total size of user buffer area
2008  * @flags: receive flags
2009  *
2010  * Used for SOCK_STREAM messages only.  If not enough data is available
2011  * will optionally wait for more; never truncates data.
2012  *
2013  * Return: size of returned message data, errno otherwise
2014  */
2015 static int tipc_recvstream(struct socket *sock, struct msghdr *m,
2016 			   size_t buflen, int flags)
2017 {
2018 	struct sock *sk = sock->sk;
2019 	struct tipc_sock *tsk = tipc_sk(sk);
2020 	struct sk_buff *skb;
2021 	struct tipc_msg *hdr;
2022 	struct tipc_skb_cb *skb_cb;
2023 	bool peek = flags & MSG_PEEK;
2024 	int offset, required, copy, copied = 0;
2025 	int hlen, dlen, err, rc;
2026 	long timeout;
2027 
2028 	/* Catch invalid receive attempts */
2029 	if (unlikely(!buflen))
2030 		return -EINVAL;
2031 
2032 	lock_sock(sk);
2033 
2034 	if (unlikely(sk->sk_state == TIPC_OPEN)) {
2035 		rc = -ENOTCONN;
2036 		goto exit;
2037 	}
2038 	required = sock_rcvlowat(sk, flags & MSG_WAITALL, buflen);
2039 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
2040 
2041 	do {
2042 		/* Look at first msg in receive queue; wait if necessary */
2043 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
2044 		if (unlikely(rc))
2045 			break;
2046 		skb = skb_peek(&sk->sk_receive_queue);
2047 		skb_cb = TIPC_SKB_CB(skb);
2048 		hdr = buf_msg(skb);
2049 		dlen = msg_data_sz(hdr);
2050 		hlen = msg_hdr_sz(hdr);
2051 		err = msg_errcode(hdr);
2052 
2053 		/* Discard any empty non-errored (SYN-) message */
2054 		if (unlikely(!dlen && !err)) {
2055 			tsk_advance_rx_queue(sk);
2056 			continue;
2057 		}
2058 
2059 		/* Collect msg meta data, incl. error code and rejected data */
2060 		if (!copied) {
2061 			tipc_sk_set_orig_addr(m, skb);
2062 			rc = tipc_sk_anc_data_recv(m, skb, tsk);
2063 			if (rc)
2064 				break;
2065 			hdr = buf_msg(skb);
2066 		}
2067 
2068 		/* Copy data if msg ok, otherwise return error/partial data */
2069 		if (likely(!err)) {
2070 			offset = skb_cb->bytes_read;
2071 			copy = min_t(size_t, dlen - offset, buflen - copied);
2072 			rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
2073 			if (unlikely(rc))
2074 				break;
2075 			copied += copy;
2076 			offset += copy;
2077 			if (unlikely(offset < dlen)) {
2078 				if (!peek)
2079 					skb_cb->bytes_read = offset;
2080 				break;
2081 			}
2082 		} else {
2083 			rc = 0;
2084 			if ((err != TIPC_CONN_SHUTDOWN) && !m->msg_control)
2085 				rc = -ECONNRESET;
2086 			if (copied || rc)
2087 				break;
2088 		}
2089 
2090 		if (unlikely(peek))
2091 			break;
2092 
2093 		tsk_advance_rx_queue(sk);
2094 
2095 		/* Send connection flow control advertisement when applicable */
2096 		tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
2097 		if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
2098 			tipc_sk_send_ack(tsk);
2099 
2100 		/* Exit if all requested data or FIN/error received */
2101 		if (copied == buflen || err)
2102 			break;
2103 
2104 	} while (!skb_queue_empty(&sk->sk_receive_queue) || copied < required);
2105 exit:
2106 	release_sock(sk);
2107 	return copied ? copied : rc;
2108 }
2109 
2110 /**
2111  * tipc_write_space - wake up thread if port congestion is released
2112  * @sk: socket
2113  */
2114 static void tipc_write_space(struct sock *sk)
2115 {
2116 	struct socket_wq *wq;
2117 
2118 	rcu_read_lock();
2119 	wq = rcu_dereference(sk->sk_wq);
2120 	if (skwq_has_sleeper(wq))
2121 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2122 						EPOLLWRNORM | EPOLLWRBAND);
2123 	rcu_read_unlock();
2124 }
2125 
2126 /**
2127  * tipc_data_ready - wake up threads to indicate messages have been received
2128  * @sk: socket
2129  */
2130 static void tipc_data_ready(struct sock *sk)
2131 {
2132 	struct socket_wq *wq;
2133 
2134 	trace_sk_data_ready(sk);
2135 
2136 	rcu_read_lock();
2137 	wq = rcu_dereference(sk->sk_wq);
2138 	if (skwq_has_sleeper(wq))
2139 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
2140 						EPOLLRDNORM | EPOLLRDBAND);
2141 	rcu_read_unlock();
2142 }
2143 
2144 static void tipc_sock_destruct(struct sock *sk)
2145 {
2146 	__skb_queue_purge(&sk->sk_receive_queue);
2147 }
2148 
2149 static void tipc_sk_proto_rcv(struct sock *sk,
2150 			      struct sk_buff_head *inputq,
2151 			      struct sk_buff_head *xmitq)
2152 {
2153 	struct sk_buff *skb = __skb_dequeue(inputq);
2154 	struct tipc_sock *tsk = tipc_sk(sk);
2155 	struct tipc_msg *hdr = buf_msg(skb);
2156 	struct tipc_group *grp = tsk->group;
2157 	bool wakeup = false;
2158 
2159 	switch (msg_user(hdr)) {
2160 	case CONN_MANAGER:
2161 		tipc_sk_conn_proto_rcv(tsk, skb, inputq, xmitq);
2162 		return;
2163 	case SOCK_WAKEUP:
2164 		tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0);
2165 		/* coupled with smp_rmb() in tipc_wait_for_cond() */
2166 		smp_wmb();
2167 		tsk->cong_link_cnt--;
2168 		wakeup = true;
2169 		tipc_sk_push_backlog(tsk, false);
2170 		break;
2171 	case GROUP_PROTOCOL:
2172 		tipc_group_proto_rcv(grp, &wakeup, hdr, inputq, xmitq);
2173 		break;
2174 	case TOP_SRV:
2175 		tipc_group_member_evt(tsk->group, &wakeup, &sk->sk_rcvbuf,
2176 				      hdr, inputq, xmitq);
2177 		break;
2178 	default:
2179 		break;
2180 	}
2181 
2182 	if (wakeup)
2183 		sk->sk_write_space(sk);
2184 
2185 	kfree_skb(skb);
2186 }
2187 
2188 /**
2189  * tipc_sk_filter_connect - check incoming message for a connection-based socket
2190  * @tsk: TIPC socket
2191  * @skb: pointer to message buffer.
2192  * @xmitq: for Nagle ACK if any
2193  * Return: true if message should be added to receive queue, false otherwise
2194  */
2195 static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb,
2196 				   struct sk_buff_head *xmitq)
2197 {
2198 	struct sock *sk = &tsk->sk;
2199 	struct net *net = sock_net(sk);
2200 	struct tipc_msg *hdr = buf_msg(skb);
2201 	bool con_msg = msg_connected(hdr);
2202 	u32 pport = tsk_peer_port(tsk);
2203 	u32 pnode = tsk_peer_node(tsk);
2204 	u32 oport = msg_origport(hdr);
2205 	u32 onode = msg_orignode(hdr);
2206 	int err = msg_errcode(hdr);
2207 	unsigned long delay;
2208 
2209 	if (unlikely(msg_mcast(hdr)))
2210 		return false;
2211 	tsk->oneway = 0;
2212 
2213 	switch (sk->sk_state) {
2214 	case TIPC_CONNECTING:
2215 		/* Setup ACK */
2216 		if (likely(con_msg)) {
2217 			if (err)
2218 				break;
2219 			tipc_sk_finish_conn(tsk, oport, onode);
2220 			msg_set_importance(&tsk->phdr, msg_importance(hdr));
2221 			/* ACK+ message with data is added to receive queue */
2222 			if (msg_data_sz(hdr))
2223 				return true;
2224 			/* Empty ACK-, - wake up sleeping connect() and drop */
2225 			sk->sk_state_change(sk);
2226 			msg_set_dest_droppable(hdr, 1);
2227 			return false;
2228 		}
2229 		/* Ignore connectionless message if not from listening socket */
2230 		if (oport != pport || onode != pnode)
2231 			return false;
2232 
2233 		/* Rejected SYN */
2234 		if (err != TIPC_ERR_OVERLOAD)
2235 			break;
2236 
2237 		/* Prepare for new setup attempt if we have a SYN clone */
2238 		if (skb_queue_empty(&sk->sk_write_queue))
2239 			break;
2240 		get_random_bytes(&delay, 2);
2241 		if (tsk->conn_timeout < 4)
2242 			tsk->conn_timeout = 4;
2243 		delay %= (tsk->conn_timeout / 4);
2244 		delay = msecs_to_jiffies(delay + 100);
2245 		sk_reset_timer(sk, &sk->sk_timer, jiffies + delay);
2246 		return false;
2247 	case TIPC_OPEN:
2248 	case TIPC_DISCONNECTING:
2249 		return false;
2250 	case TIPC_LISTEN:
2251 		/* Accept only SYN message */
2252 		if (!msg_is_syn(hdr) &&
2253 		    tipc_node_get_capabilities(net, onode) & TIPC_SYN_BIT)
2254 			return false;
2255 		if (!con_msg && !err)
2256 			return true;
2257 		return false;
2258 	case TIPC_ESTABLISHED:
2259 		if (!skb_queue_empty(&sk->sk_write_queue))
2260 			tipc_sk_push_backlog(tsk, false);
2261 		/* Accept only connection-based messages sent by peer */
2262 		if (likely(con_msg && !err && pport == oport &&
2263 			   pnode == onode)) {
2264 			if (msg_ack_required(hdr)) {
2265 				struct sk_buff *skb;
2266 
2267 				skb = tipc_sk_build_ack(tsk);
2268 				if (skb) {
2269 					msg_set_nagle_ack(buf_msg(skb));
2270 					__skb_queue_tail(xmitq, skb);
2271 				}
2272 			}
2273 			return true;
2274 		}
2275 		if (!tsk_peer_msg(tsk, hdr))
2276 			return false;
2277 		if (!err)
2278 			return true;
2279 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2280 		tipc_node_remove_conn(net, pnode, tsk->portid);
2281 		sk->sk_state_change(sk);
2282 		return true;
2283 	default:
2284 		pr_err("Unknown sk_state %u\n", sk->sk_state);
2285 	}
2286 	/* Abort connection setup attempt */
2287 	tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2288 	sk->sk_err = ECONNREFUSED;
2289 	sk->sk_state_change(sk);
2290 	return true;
2291 }
2292 
2293 /**
2294  * rcvbuf_limit - get proper overload limit of socket receive queue
2295  * @sk: socket
2296  * @skb: message
2297  *
2298  * For connection oriented messages, irrespective of importance,
2299  * default queue limit is 2 MB.
2300  *
2301  * For connectionless messages, queue limits are based on message
2302  * importance as follows:
2303  *
2304  * TIPC_LOW_IMPORTANCE       (2 MB)
2305  * TIPC_MEDIUM_IMPORTANCE    (4 MB)
2306  * TIPC_HIGH_IMPORTANCE      (8 MB)
2307  * TIPC_CRITICAL_IMPORTANCE  (16 MB)
2308  *
2309  * Return: overload limit according to corresponding message importance
2310  */
2311 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb)
2312 {
2313 	struct tipc_sock *tsk = tipc_sk(sk);
2314 	struct tipc_msg *hdr = buf_msg(skb);
2315 
2316 	if (unlikely(msg_in_group(hdr)))
2317 		return READ_ONCE(sk->sk_rcvbuf);
2318 
2319 	if (unlikely(!msg_connected(hdr)))
2320 		return READ_ONCE(sk->sk_rcvbuf) << msg_importance(hdr);
2321 
2322 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
2323 		return READ_ONCE(sk->sk_rcvbuf);
2324 
2325 	return FLOWCTL_MSG_LIM;
2326 }
2327 
2328 /**
2329  * tipc_sk_filter_rcv - validate incoming message
2330  * @sk: socket
2331  * @skb: pointer to message.
2332  * @xmitq: output message area (FIXME)
2333  *
2334  * Enqueues message on receive queue if acceptable; optionally handles
2335  * disconnect indication for a connected socket.
2336  *
2337  * Called with socket lock already taken
2338  */
2339 static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb,
2340 			       struct sk_buff_head *xmitq)
2341 {
2342 	bool sk_conn = !tipc_sk_type_connectionless(sk);
2343 	struct tipc_sock *tsk = tipc_sk(sk);
2344 	struct tipc_group *grp = tsk->group;
2345 	struct tipc_msg *hdr = buf_msg(skb);
2346 	struct net *net = sock_net(sk);
2347 	struct sk_buff_head inputq;
2348 	int mtyp = msg_type(hdr);
2349 	int limit, err = TIPC_OK;
2350 
2351 	trace_tipc_sk_filter_rcv(sk, skb, TIPC_DUMP_ALL, " ");
2352 	TIPC_SKB_CB(skb)->bytes_read = 0;
2353 	__skb_queue_head_init(&inputq);
2354 	__skb_queue_tail(&inputq, skb);
2355 
2356 	if (unlikely(!msg_isdata(hdr)))
2357 		tipc_sk_proto_rcv(sk, &inputq, xmitq);
2358 
2359 	if (unlikely(grp))
2360 		tipc_group_filter_msg(grp, &inputq, xmitq);
2361 
2362 	if (unlikely(!grp) && mtyp == TIPC_MCAST_MSG)
2363 		tipc_mcast_filter_msg(net, &tsk->mc_method.deferredq, &inputq);
2364 
2365 	/* Validate and add to receive buffer if there is space */
2366 	while ((skb = __skb_dequeue(&inputq))) {
2367 		hdr = buf_msg(skb);
2368 		limit = rcvbuf_limit(sk, skb);
2369 		if ((sk_conn && !tipc_sk_filter_connect(tsk, skb, xmitq)) ||
2370 		    (!sk_conn && msg_connected(hdr)) ||
2371 		    (!grp && msg_in_group(hdr)))
2372 			err = TIPC_ERR_NO_PORT;
2373 		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit) {
2374 			trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL,
2375 					   "err_overload2!");
2376 			sk_drops_inc(sk);
2377 			err = TIPC_ERR_OVERLOAD;
2378 		}
2379 
2380 		if (unlikely(err)) {
2381 			if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) {
2382 				trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE,
2383 						      "@filter_rcv!");
2384 				__skb_queue_tail(xmitq, skb);
2385 			}
2386 			err = TIPC_OK;
2387 			continue;
2388 		}
2389 		__skb_queue_tail(&sk->sk_receive_queue, skb);
2390 		skb_set_owner_r(skb, sk);
2391 		trace_tipc_sk_overlimit2(sk, skb, TIPC_DUMP_ALL,
2392 					 "rcvq >90% allocated!");
2393 		sk->sk_data_ready(sk);
2394 	}
2395 }
2396 
2397 /**
2398  * tipc_sk_backlog_rcv - handle incoming message from backlog queue
2399  * @sk: socket
2400  * @skb: message
2401  *
2402  * Caller must hold socket lock
2403  */
2404 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
2405 {
2406 	unsigned int before = sk_rmem_alloc_get(sk);
2407 	struct sk_buff_head xmitq;
2408 	unsigned int added;
2409 
2410 	__skb_queue_head_init(&xmitq);
2411 
2412 	tipc_sk_filter_rcv(sk, skb, &xmitq);
2413 	added = sk_rmem_alloc_get(sk) - before;
2414 	atomic_add(added, &tipc_sk(sk)->dupl_rcvcnt);
2415 
2416 	/* Send pending response/rejected messages, if any */
2417 	tipc_node_distr_xmit(sock_net(sk), &xmitq);
2418 	return 0;
2419 }
2420 
2421 /**
2422  * tipc_sk_enqueue - extract all buffers with destination 'dport' from
2423  *                   inputq and try adding them to socket or backlog queue
2424  * @inputq: list of incoming buffers with potentially different destinations
2425  * @sk: socket where the buffers should be enqueued
2426  * @dport: port number for the socket
2427  * @xmitq: output queue
2428  *
2429  * Caller must hold socket lock
2430  */
2431 static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
2432 			    u32 dport, struct sk_buff_head *xmitq)
2433 {
2434 	unsigned long time_limit = jiffies + usecs_to_jiffies(20000);
2435 	struct sk_buff *skb;
2436 	unsigned int lim;
2437 	atomic_t *dcnt;
2438 	u32 onode;
2439 
2440 	while (skb_queue_len(inputq)) {
2441 		if (unlikely(time_after_eq(jiffies, time_limit)))
2442 			return;
2443 
2444 		skb = tipc_skb_dequeue(inputq, dport);
2445 		if (unlikely(!skb))
2446 			return;
2447 
2448 		/* Add message directly to receive queue if possible */
2449 		if (!sock_owned_by_user(sk)) {
2450 			tipc_sk_filter_rcv(sk, skb, xmitq);
2451 			continue;
2452 		}
2453 
2454 		/* Try backlog, compensating for double-counted bytes */
2455 		dcnt = &tipc_sk(sk)->dupl_rcvcnt;
2456 		if (!sk->sk_backlog.len)
2457 			atomic_set(dcnt, 0);
2458 		lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
2459 		if (likely(!sk_add_backlog(sk, skb, lim))) {
2460 			trace_tipc_sk_overlimit1(sk, skb, TIPC_DUMP_SK_BKLGQ,
2461 						 "bklg & rcvq >90% allocated!");
2462 			continue;
2463 		}
2464 
2465 		trace_tipc_sk_dump(sk, skb, TIPC_DUMP_SK_BKLGQ, "err_overload!");
2466 		/* Overload => reject message back to sender */
2467 		onode = tipc_own_addr(sock_net(sk));
2468 		sk_drops_inc(sk);
2469 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD)) {
2470 			trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_SK_BKLGQ,
2471 					      "@sk_enqueue!");
2472 			__skb_queue_tail(xmitq, skb);
2473 		}
2474 		break;
2475 	}
2476 }
2477 
2478 /**
2479  * tipc_sk_rcv - handle a chain of incoming buffers
2480  * @net: the associated network namespace
2481  * @inputq: buffer list containing the buffers
2482  * Consumes all buffers in list until inputq is empty
2483  * Note: may be called in multiple threads referring to the same queue
2484  */
2485 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq)
2486 {
2487 	struct sk_buff_head xmitq;
2488 	u32 dnode, dport = 0;
2489 	int err;
2490 	struct tipc_sock *tsk;
2491 	struct sock *sk;
2492 	struct sk_buff *skb;
2493 
2494 	__skb_queue_head_init(&xmitq);
2495 	while (skb_queue_len(inputq)) {
2496 		dport = tipc_skb_peek_port(inputq, dport);
2497 		tsk = tipc_sk_lookup(net, dport);
2498 
2499 		if (likely(tsk)) {
2500 			sk = &tsk->sk;
2501 			if (likely(spin_trylock_bh(&sk->sk_lock.slock))) {
2502 				tipc_sk_enqueue(inputq, sk, dport, &xmitq);
2503 				spin_unlock_bh(&sk->sk_lock.slock);
2504 			}
2505 			/* Send pending response/rejected messages, if any */
2506 			tipc_node_distr_xmit(sock_net(sk), &xmitq);
2507 			sock_put(sk);
2508 			continue;
2509 		}
2510 		/* No destination socket => dequeue skb if still there */
2511 		skb = tipc_skb_dequeue(inputq, dport);
2512 		if (!skb)
2513 			return;
2514 
2515 		/* Try secondary lookup if unresolved named message */
2516 		err = TIPC_ERR_NO_PORT;
2517 		if (tipc_msg_lookup_dest(net, skb, &err))
2518 			goto xmit;
2519 
2520 		/* Prepare for message rejection */
2521 		if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err))
2522 			continue;
2523 
2524 		trace_tipc_sk_rej_msg(NULL, skb, TIPC_DUMP_NONE, "@sk_rcv!");
2525 xmit:
2526 		dnode = msg_destnode(buf_msg(skb));
2527 		tipc_node_xmit_skb(net, skb, dnode, dport);
2528 	}
2529 }
2530 
2531 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
2532 {
2533 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2534 	struct sock *sk = sock->sk;
2535 	int done;
2536 
2537 	do {
2538 		int err = sock_error(sk);
2539 		if (err)
2540 			return err;
2541 		if (!*timeo_p)
2542 			return -ETIMEDOUT;
2543 		if (signal_pending(current))
2544 			return sock_intr_errno(*timeo_p);
2545 		if (sk->sk_state == TIPC_DISCONNECTING)
2546 			break;
2547 
2548 		add_wait_queue(sk_sleep(sk), &wait);
2549 		done = sk_wait_event(sk, timeo_p, tipc_sk_connected(sk),
2550 				     &wait);
2551 		remove_wait_queue(sk_sleep(sk), &wait);
2552 	} while (!done);
2553 	return 0;
2554 }
2555 
2556 static bool tipc_sockaddr_is_sane(struct sockaddr_tipc *addr)
2557 {
2558 	if (addr->family != AF_TIPC)
2559 		return false;
2560 	if (addr->addrtype == TIPC_SERVICE_RANGE)
2561 		return (addr->addr.nameseq.lower <= addr->addr.nameseq.upper);
2562 	return (addr->addrtype == TIPC_SERVICE_ADDR ||
2563 		addr->addrtype == TIPC_SOCKET_ADDR);
2564 }
2565 
2566 /**
2567  * tipc_connect - establish a connection to another TIPC port
2568  * @sock: socket structure
2569  * @dest: socket address for destination port
2570  * @destlen: size of socket address data structure
2571  * @flags: file-related flags associated with socket
2572  *
2573  * Return: 0 on success, errno otherwise
2574  */
2575 static int tipc_connect(struct socket *sock, struct sockaddr_unsized *dest,
2576 			int destlen, int flags)
2577 {
2578 	struct sock *sk = sock->sk;
2579 	struct tipc_sock *tsk = tipc_sk(sk);
2580 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
2581 	struct msghdr m = {NULL,};
2582 	long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout;
2583 	int previous;
2584 	int res = 0;
2585 
2586 	if (destlen != sizeof(struct sockaddr_tipc))
2587 		return -EINVAL;
2588 
2589 	lock_sock(sk);
2590 
2591 	if (tsk->group) {
2592 		res = -EINVAL;
2593 		goto exit;
2594 	}
2595 
2596 	if (dst->family == AF_UNSPEC) {
2597 		memset(&tsk->peer, 0, sizeof(struct sockaddr_tipc));
2598 		if (!tipc_sk_type_connectionless(sk))
2599 			res = -EINVAL;
2600 		goto exit;
2601 	}
2602 	if (!tipc_sockaddr_is_sane(dst)) {
2603 		res = -EINVAL;
2604 		goto exit;
2605 	}
2606 	/* DGRAM/RDM connect(), just save the destaddr */
2607 	if (tipc_sk_type_connectionless(sk)) {
2608 		memcpy(&tsk->peer, dest, destlen);
2609 		goto exit;
2610 	} else if (dst->addrtype == TIPC_SERVICE_RANGE) {
2611 		res = -EINVAL;
2612 		goto exit;
2613 	}
2614 
2615 	previous = sk->sk_state;
2616 
2617 	switch (sk->sk_state) {
2618 	case TIPC_OPEN:
2619 		/* Send a 'SYN-' to destination */
2620 		m.msg_name = dest;
2621 		m.msg_namelen = destlen;
2622 		iov_iter_kvec(&m.msg_iter, ITER_SOURCE, NULL, 0, 0);
2623 
2624 		/* If connect is in non-blocking case, set MSG_DONTWAIT to
2625 		 * indicate send_msg() is never blocked.
2626 		 */
2627 		if (!timeout)
2628 			m.msg_flags = MSG_DONTWAIT;
2629 
2630 		res = __tipc_sendmsg(sock, &m, 0);
2631 		if ((res < 0) && (res != -EWOULDBLOCK))
2632 			goto exit;
2633 
2634 		/* Just entered TIPC_CONNECTING state; the only
2635 		 * difference is that return value in non-blocking
2636 		 * case is EINPROGRESS, rather than EALREADY.
2637 		 */
2638 		res = -EINPROGRESS;
2639 		fallthrough;
2640 	case TIPC_CONNECTING:
2641 		if (!timeout) {
2642 			if (previous == TIPC_CONNECTING)
2643 				res = -EALREADY;
2644 			goto exit;
2645 		}
2646 		timeout = msecs_to_jiffies(timeout);
2647 		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
2648 		res = tipc_wait_for_connect(sock, &timeout);
2649 		break;
2650 	case TIPC_ESTABLISHED:
2651 		res = -EISCONN;
2652 		break;
2653 	default:
2654 		res = -EINVAL;
2655 	}
2656 
2657 exit:
2658 	release_sock(sk);
2659 	return res;
2660 }
2661 
2662 /**
2663  * tipc_listen - allow socket to listen for incoming connections
2664  * @sock: socket structure
2665  * @len: (unused)
2666  *
2667  * Return: 0 on success, errno otherwise
2668  */
2669 static int tipc_listen(struct socket *sock, int len)
2670 {
2671 	struct sock *sk = sock->sk;
2672 	int res;
2673 
2674 	lock_sock(sk);
2675 	res = tipc_set_sk_state(sk, TIPC_LISTEN);
2676 	release_sock(sk);
2677 
2678 	return res;
2679 }
2680 
2681 static int tipc_wait_for_accept(struct socket *sock, long timeo)
2682 {
2683 	struct sock *sk = sock->sk;
2684 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2685 	int err;
2686 
2687 	/* True wake-one mechanism for incoming connections: only
2688 	 * one process gets woken up, not the 'whole herd'.
2689 	 * Since we do not 'race & poll' for established sockets
2690 	 * anymore, the common case will execute the loop only once.
2691 	*/
2692 	for (;;) {
2693 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
2694 			add_wait_queue(sk_sleep(sk), &wait);
2695 			release_sock(sk);
2696 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
2697 			lock_sock(sk);
2698 			remove_wait_queue(sk_sleep(sk), &wait);
2699 		}
2700 		err = 0;
2701 		if (!skb_queue_empty(&sk->sk_receive_queue))
2702 			break;
2703 		err = -EAGAIN;
2704 		if (!timeo)
2705 			break;
2706 		err = sock_intr_errno(timeo);
2707 		if (signal_pending(current))
2708 			break;
2709 	}
2710 	return err;
2711 }
2712 
2713 /**
2714  * tipc_accept - wait for connection request
2715  * @sock: listening socket
2716  * @new_sock: new socket that is to be connected
2717  * @arg: arguments for accept
2718  *
2719  * Return: 0 on success, errno otherwise
2720  */
2721 static int tipc_accept(struct socket *sock, struct socket *new_sock,
2722 		       struct proto_accept_arg *arg)
2723 {
2724 	struct sock *new_sk, *sk = sock->sk;
2725 	struct tipc_sock *new_tsock;
2726 	struct msghdr m = {NULL,};
2727 	struct tipc_msg *msg;
2728 	struct sk_buff *buf;
2729 	long timeo;
2730 	int res;
2731 
2732 	lock_sock(sk);
2733 
2734 	if (sk->sk_state != TIPC_LISTEN) {
2735 		res = -EINVAL;
2736 		goto exit;
2737 	}
2738 	timeo = sock_rcvtimeo(sk, arg->flags & O_NONBLOCK);
2739 	res = tipc_wait_for_accept(sock, timeo);
2740 	if (res)
2741 		goto exit;
2742 
2743 	buf = skb_peek(&sk->sk_receive_queue);
2744 
2745 	res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, arg->kern);
2746 	if (res)
2747 		goto exit;
2748 	security_sk_clone(sock->sk, new_sock->sk);
2749 
2750 	new_sk = new_sock->sk;
2751 	new_tsock = tipc_sk(new_sk);
2752 	msg = buf_msg(buf);
2753 
2754 	/* we lock on new_sk; but lockdep sees the lock on sk */
2755 	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
2756 
2757 	/*
2758 	 * Reject any stray messages received by new socket
2759 	 * before the socket lock was taken (very, very unlikely)
2760 	 */
2761 	tsk_rej_rx_queue(new_sk, TIPC_ERR_NO_PORT);
2762 
2763 	/* Connect new socket to it's peer */
2764 	tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg));
2765 
2766 	tsk_set_importance(new_sk, msg_importance(msg));
2767 	if (msg_named(msg)) {
2768 		new_tsock->conn_addrtype = TIPC_SERVICE_ADDR;
2769 		msg_set_nametype(&new_tsock->phdr, msg_nametype(msg));
2770 		msg_set_nameinst(&new_tsock->phdr, msg_nameinst(msg));
2771 	}
2772 
2773 	/*
2774 	 * Respond to 'SYN-' by discarding it & returning 'ACK'.
2775 	 * Respond to 'SYN+' by queuing it on new socket & returning 'ACK'.
2776 	 */
2777 	if (!msg_data_sz(msg)) {
2778 		tsk_advance_rx_queue(sk);
2779 	} else {
2780 		__skb_dequeue(&sk->sk_receive_queue);
2781 		__skb_queue_head(&new_sk->sk_receive_queue, buf);
2782 		skb_set_owner_r(buf, new_sk);
2783 	}
2784 	iov_iter_kvec(&m.msg_iter, ITER_SOURCE, NULL, 0, 0);
2785 	__tipc_sendstream(new_sock, &m, 0);
2786 	release_sock(new_sk);
2787 exit:
2788 	release_sock(sk);
2789 	return res;
2790 }
2791 
2792 /**
2793  * tipc_shutdown - shutdown socket connection
2794  * @sock: socket structure
2795  * @how: direction to close (must be SHUT_RDWR)
2796  *
2797  * Terminates connection (if necessary), then purges socket's receive queue.
2798  *
2799  * Return: 0 on success, errno otherwise
2800  */
2801 static int tipc_shutdown(struct socket *sock, int how)
2802 {
2803 	struct sock *sk = sock->sk;
2804 	int res;
2805 
2806 	if (how != SHUT_RDWR)
2807 		return -EINVAL;
2808 
2809 	lock_sock(sk);
2810 
2811 	trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " ");
2812 	__tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
2813 	sk->sk_shutdown = SHUTDOWN_MASK;
2814 
2815 	if (sk->sk_state == TIPC_DISCONNECTING) {
2816 		/* Discard any unreceived messages */
2817 		__skb_queue_purge(&sk->sk_receive_queue);
2818 
2819 		res = 0;
2820 	} else {
2821 		res = -ENOTCONN;
2822 	}
2823 	/* Wake up anyone sleeping in poll. */
2824 	sk->sk_state_change(sk);
2825 
2826 	release_sock(sk);
2827 	return res;
2828 }
2829 
2830 static void tipc_sk_check_probing_state(struct sock *sk,
2831 					struct sk_buff_head *list)
2832 {
2833 	struct tipc_sock *tsk = tipc_sk(sk);
2834 	u32 pnode = tsk_peer_node(tsk);
2835 	u32 pport = tsk_peer_port(tsk);
2836 	u32 self = tsk_own_node(tsk);
2837 	u32 oport = tsk->portid;
2838 	struct sk_buff *skb;
2839 
2840 	if (tsk->probe_unacked) {
2841 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2842 		sk->sk_err = ECONNABORTED;
2843 		tipc_node_remove_conn(sock_net(sk), pnode, pport);
2844 		sk->sk_state_change(sk);
2845 		return;
2846 	}
2847 	/* Prepare new probe */
2848 	skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE, INT_H_SIZE, 0,
2849 			      pnode, self, pport, oport, TIPC_OK);
2850 	if (skb)
2851 		__skb_queue_tail(list, skb);
2852 	tsk->probe_unacked = true;
2853 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
2854 }
2855 
2856 static void tipc_sk_retry_connect(struct sock *sk, struct sk_buff_head *list)
2857 {
2858 	struct tipc_sock *tsk = tipc_sk(sk);
2859 
2860 	/* Try again later if dest link is congested */
2861 	if (tsk->cong_link_cnt) {
2862 		sk_reset_timer(sk, &sk->sk_timer,
2863 			       jiffies + msecs_to_jiffies(100));
2864 		return;
2865 	}
2866 	/* Prepare SYN for retransmit */
2867 	tipc_msg_skb_clone(&sk->sk_write_queue, list);
2868 }
2869 
2870 static void tipc_sk_timeout(struct timer_list *t)
2871 {
2872 	struct sock *sk = timer_container_of(sk, t, sk_timer);
2873 	struct tipc_sock *tsk = tipc_sk(sk);
2874 	u32 pnode = tsk_peer_node(tsk);
2875 	struct sk_buff_head list;
2876 	int rc = 0;
2877 
2878 	__skb_queue_head_init(&list);
2879 	bh_lock_sock(sk);
2880 
2881 	/* Try again later if socket is busy */
2882 	if (sock_owned_by_user(sk)) {
2883 		sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 20);
2884 		bh_unlock_sock(sk);
2885 		sock_put(sk);
2886 		return;
2887 	}
2888 
2889 	if (sk->sk_state == TIPC_ESTABLISHED)
2890 		tipc_sk_check_probing_state(sk, &list);
2891 	else if (sk->sk_state == TIPC_CONNECTING)
2892 		tipc_sk_retry_connect(sk, &list);
2893 
2894 	bh_unlock_sock(sk);
2895 
2896 	if (!skb_queue_empty(&list))
2897 		rc = tipc_node_xmit(sock_net(sk), &list, pnode, tsk->portid);
2898 
2899 	/* SYN messages may cause link congestion */
2900 	if (rc == -ELINKCONG) {
2901 		tipc_dest_push(&tsk->cong_links, pnode, 0);
2902 		tsk->cong_link_cnt = 1;
2903 	}
2904 	sock_put(sk);
2905 }
2906 
2907 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2908 {
2909 	struct sock *sk = &tsk->sk;
2910 	struct net *net = sock_net(sk);
2911 	struct tipc_socket_addr skaddr;
2912 	struct publication *p;
2913 	u32 key;
2914 
2915 	if (tipc_sk_connected(sk))
2916 		return -EINVAL;
2917 	key = tsk->portid + tsk->pub_count + 1;
2918 	if (key == tsk->portid)
2919 		return -EADDRINUSE;
2920 	skaddr.ref = tsk->portid;
2921 	skaddr.node = tipc_own_addr(net);
2922 	p = tipc_nametbl_publish(net, ua, &skaddr, key);
2923 	if (unlikely(!p))
2924 		return -EINVAL;
2925 
2926 	list_add(&p->binding_sock, &tsk->publications);
2927 	tsk->pub_count++;
2928 	tsk->published = true;
2929 	return 0;
2930 }
2931 
2932 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2933 {
2934 	struct net *net = sock_net(&tsk->sk);
2935 	struct publication *safe, *p;
2936 	struct tipc_uaddr _ua;
2937 	int rc = -EINVAL;
2938 
2939 	list_for_each_entry_safe(p, safe, &tsk->publications, binding_sock) {
2940 		if (!ua) {
2941 			tipc_uaddr(&_ua, TIPC_SERVICE_RANGE, p->scope,
2942 				   p->sr.type, p->sr.lower, p->sr.upper);
2943 			tipc_nametbl_withdraw(net, &_ua, &p->sk, p->key);
2944 			continue;
2945 		}
2946 		/* Unbind specific publication */
2947 		if (p->scope != ua->scope)
2948 			continue;
2949 		if (p->sr.type != ua->sr.type)
2950 			continue;
2951 		if (p->sr.lower != ua->sr.lower)
2952 			continue;
2953 		if (p->sr.upper != ua->sr.upper)
2954 			break;
2955 		tipc_nametbl_withdraw(net, ua, &p->sk, p->key);
2956 		rc = 0;
2957 		break;
2958 	}
2959 	if (list_empty(&tsk->publications)) {
2960 		tsk->published = 0;
2961 		rc = 0;
2962 	}
2963 	return rc;
2964 }
2965 
2966 /* tipc_sk_reinit: set non-zero address in all existing sockets
2967  *                 when we go from standalone to network mode.
2968  */
2969 void tipc_sk_reinit(struct net *net)
2970 {
2971 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2972 	struct rhashtable_iter iter;
2973 	struct tipc_sock *tsk;
2974 	struct tipc_msg *msg;
2975 
2976 	rhashtable_walk_enter(&tn->sk_rht, &iter);
2977 
2978 	do {
2979 		rhashtable_walk_start(&iter);
2980 
2981 		while ((tsk = rhashtable_walk_next(&iter)) && !IS_ERR(tsk)) {
2982 			sock_hold(&tsk->sk);
2983 			rhashtable_walk_stop(&iter);
2984 			lock_sock(&tsk->sk);
2985 			msg = &tsk->phdr;
2986 			msg_set_prevnode(msg, tipc_own_addr(net));
2987 			msg_set_orignode(msg, tipc_own_addr(net));
2988 			release_sock(&tsk->sk);
2989 			rhashtable_walk_start(&iter);
2990 			sock_put(&tsk->sk);
2991 		}
2992 
2993 		rhashtable_walk_stop(&iter);
2994 	} while (tsk == ERR_PTR(-EAGAIN));
2995 
2996 	rhashtable_walk_exit(&iter);
2997 }
2998 
2999 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)
3000 {
3001 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3002 	struct tipc_sock *tsk;
3003 
3004 	rcu_read_lock();
3005 	tsk = rhashtable_lookup(&tn->sk_rht, &portid, tsk_rht_params);
3006 	if (tsk)
3007 		sock_hold(&tsk->sk);
3008 	rcu_read_unlock();
3009 
3010 	return tsk;
3011 }
3012 
3013 static int tipc_sk_insert(struct tipc_sock *tsk)
3014 {
3015 	struct sock *sk = &tsk->sk;
3016 	struct net *net = sock_net(sk);
3017 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3018 	u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1;
3019 	u32 portid = get_random_u32_below(remaining) + TIPC_MIN_PORT;
3020 
3021 	while (remaining--) {
3022 		portid++;
3023 		if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT))
3024 			portid = TIPC_MIN_PORT;
3025 		tsk->portid = portid;
3026 		sock_hold(&tsk->sk);
3027 		if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node,
3028 						   tsk_rht_params))
3029 			return 0;
3030 		sock_put(&tsk->sk);
3031 	}
3032 
3033 	return -1;
3034 }
3035 
3036 static void tipc_sk_remove(struct tipc_sock *tsk)
3037 {
3038 	struct sock *sk = &tsk->sk;
3039 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
3040 
3041 	if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params))
3042 		__sock_put(sk);
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  * @sopt: socket option container (input buffer length, output value/length)
3229  *
3230  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
3231  * (to ease compatibility).
3232  *
3233  * Return: 0 on success, errno otherwise
3234  */
3235 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
3236 			   sockopt_t *sopt)
3237 {
3238 	struct sock *sk = sock->sk;
3239 	struct tipc_sock *tsk = tipc_sk(sk);
3240 	struct tipc_service_range seq;
3241 	int len, scope;
3242 	int res = 0;
3243 	u32 value;
3244 
3245 	if (lvl == IPPROTO_TCP && sock->type == SOCK_STREAM) {
3246 		sopt->optlen = 0;
3247 		return 0;
3248 	}
3249 	if (lvl != SOL_TIPC)
3250 		return -ENOPROTOOPT;
3251 	len = sopt->optlen;
3252 
3253 	lock_sock(sk);
3254 
3255 	switch (opt) {
3256 	case TIPC_IMPORTANCE:
3257 		value = tsk_importance(tsk);
3258 		break;
3259 	case TIPC_SRC_DROPPABLE:
3260 		value = tsk_unreliable(tsk);
3261 		break;
3262 	case TIPC_DEST_DROPPABLE:
3263 		value = tsk_unreturnable(tsk);
3264 		break;
3265 	case TIPC_CONN_TIMEOUT:
3266 		value = tsk->conn_timeout;
3267 		break;
3268 	case TIPC_NODE_RECVQ_DEPTH:
3269 		value = 0; /* was tipc_queue_size, now obsolete */
3270 		break;
3271 	case TIPC_SOCK_RECVQ_DEPTH:
3272 		value = skb_queue_len(&sk->sk_receive_queue);
3273 		break;
3274 	case TIPC_SOCK_RECVQ_USED:
3275 		value = sk_rmem_alloc_get(sk);
3276 		break;
3277 	case TIPC_GROUP_JOIN:
3278 		seq.type = 0;
3279 		if (tsk->group)
3280 			tipc_group_self(tsk->group, &seq, &scope);
3281 		value = seq.type;
3282 		break;
3283 	default:
3284 		res = -EINVAL;
3285 	}
3286 
3287 	release_sock(sk);
3288 
3289 	if (res)
3290 		return res;
3291 
3292 	if (len < sizeof(value))
3293 		return -EINVAL;
3294 
3295 	if (copy_to_iter(&value, sizeof(value), &sopt->iter_out) !=
3296 	    sizeof(value))
3297 		return -EFAULT;
3298 	sopt->optlen = sizeof(value);
3299 
3300 	return 0;
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_iter = 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_iter = 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_iter = 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 			if (PTR_ERR(tsk) == -EAGAIN)
3569 				continue;
3570 			break;
3571 		}
3572 
3573 		sock_hold(&tsk->sk);
3574 		rhashtable_walk_stop(iter);
3575 		lock_sock(&tsk->sk);
3576 		err = skb_handler(skb, cb, tsk);
3577 		if (err) {
3578 			release_sock(&tsk->sk);
3579 			sock_put(&tsk->sk);
3580 			goto out;
3581 		}
3582 		release_sock(&tsk->sk);
3583 		rhashtable_walk_start(iter);
3584 		sock_put(&tsk->sk);
3585 	}
3586 	rhashtable_walk_stop(iter);
3587 out:
3588 	return skb->len;
3589 }
3590 EXPORT_SYMBOL(tipc_nl_sk_walk);
3591 
3592 int tipc_dump_start(struct netlink_callback *cb)
3593 {
3594 	return __tipc_dump_start(cb, sock_net(cb->skb->sk));
3595 }
3596 EXPORT_SYMBOL(tipc_dump_start);
3597 
3598 int __tipc_dump_start(struct netlink_callback *cb, struct net *net)
3599 {
3600 	/* tipc_nl_name_table_dump() uses cb->args[0...3]. */
3601 	struct rhashtable_iter *iter = (void *)cb->args[4];
3602 	struct tipc_net *tn = tipc_net(net);
3603 
3604 	if (!iter) {
3605 		iter = kmalloc_obj(*iter);
3606 		if (!iter)
3607 			return -ENOMEM;
3608 
3609 		cb->args[4] = (long)iter;
3610 	}
3611 
3612 	rhashtable_walk_enter(&tn->sk_rht, iter);
3613 	return 0;
3614 }
3615 
3616 int tipc_dump_done(struct netlink_callback *cb)
3617 {
3618 	struct rhashtable_iter *hti = (void *)cb->args[4];
3619 
3620 	rhashtable_walk_exit(hti);
3621 	kfree(hti);
3622 	return 0;
3623 }
3624 EXPORT_SYMBOL(tipc_dump_done);
3625 
3626 int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct netlink_callback *cb,
3627 			   struct tipc_sock *tsk, u32 sk_filter_state,
3628 			   u64 (*tipc_diag_gen_cookie)(struct sock *sk))
3629 {
3630 	struct sock *sk = &tsk->sk;
3631 	struct nlattr *attrs;
3632 	struct nlattr *stat;
3633 
3634 	/*filter response w.r.t sk_state*/
3635 	if (!(sk_filter_state & (1 << sk->sk_state)))
3636 		return 0;
3637 
3638 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3639 	if (!attrs)
3640 		goto msg_cancel;
3641 
3642 	if (__tipc_nl_add_sk_info(skb, tsk))
3643 		goto attr_msg_cancel;
3644 
3645 	if (nla_put_u32(skb, TIPC_NLA_SOCK_TYPE, (u32)sk->sk_type) ||
3646 	    nla_put_u32(skb, TIPC_NLA_SOCK_TIPC_STATE, (u32)sk->sk_state) ||
3647 	    nla_put_u32(skb, TIPC_NLA_SOCK_INO, sock_i_ino(sk)) ||
3648 	    nla_put_u32(skb, TIPC_NLA_SOCK_UID,
3649 			from_kuid_munged(sk_user_ns(NETLINK_CB(cb->skb).sk),
3650 					 sk_uid(sk))) ||
3651 	    nla_put_u64_64bit(skb, TIPC_NLA_SOCK_COOKIE,
3652 			      tipc_diag_gen_cookie(sk),
3653 			      TIPC_NLA_SOCK_PAD))
3654 		goto attr_msg_cancel;
3655 
3656 	stat = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_STAT);
3657 	if (!stat)
3658 		goto attr_msg_cancel;
3659 
3660 	if (nla_put_u32(skb, TIPC_NLA_SOCK_STAT_RCVQ,
3661 			skb_queue_len(&sk->sk_receive_queue)) ||
3662 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_SENDQ,
3663 			skb_queue_len(&sk->sk_write_queue)) ||
3664 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_DROP,
3665 			sk_drops_read(sk)))
3666 		goto stat_msg_cancel;
3667 
3668 	if (tsk->cong_link_cnt &&
3669 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_LINK_CONG))
3670 		goto stat_msg_cancel;
3671 
3672 	if (tsk_conn_cong(tsk) &&
3673 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_CONN_CONG))
3674 		goto stat_msg_cancel;
3675 
3676 	nla_nest_end(skb, stat);
3677 
3678 	if (tsk->group)
3679 		if (tipc_group_fill_sock_diag(tsk->group, skb))
3680 			goto stat_msg_cancel;
3681 
3682 	nla_nest_end(skb, attrs);
3683 
3684 	return 0;
3685 
3686 stat_msg_cancel:
3687 	nla_nest_cancel(skb, stat);
3688 attr_msg_cancel:
3689 	nla_nest_cancel(skb, attrs);
3690 msg_cancel:
3691 	return -EMSGSIZE;
3692 }
3693 EXPORT_SYMBOL(tipc_sk_fill_sock_diag);
3694 
3695 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
3696 {
3697 	return tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk);
3698 }
3699 
3700 /* Caller should hold socket lock for the passed tipc socket. */
3701 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
3702 				 struct netlink_callback *cb,
3703 				 struct publication *publ)
3704 {
3705 	void *hdr;
3706 	struct nlattr *attrs;
3707 
3708 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3709 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET);
3710 	if (!hdr)
3711 		goto msg_cancel;
3712 
3713 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_PUBL);
3714 	if (!attrs)
3715 		goto genlmsg_cancel;
3716 
3717 	if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key))
3718 		goto attr_msg_cancel;
3719 	if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->sr.type))
3720 		goto attr_msg_cancel;
3721 	if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->sr.lower))
3722 		goto attr_msg_cancel;
3723 	if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->sr.upper))
3724 		goto attr_msg_cancel;
3725 
3726 	nla_nest_end(skb, attrs);
3727 	genlmsg_end(skb, hdr);
3728 
3729 	return 0;
3730 
3731 attr_msg_cancel:
3732 	nla_nest_cancel(skb, attrs);
3733 genlmsg_cancel:
3734 	genlmsg_cancel(skb, hdr);
3735 msg_cancel:
3736 	return -EMSGSIZE;
3737 }
3738 
3739 /* Caller should hold socket lock for the passed tipc socket. */
3740 static int __tipc_nl_list_sk_publ(struct sk_buff *skb,
3741 				  struct netlink_callback *cb,
3742 				  struct tipc_sock *tsk, u32 *last_publ)
3743 {
3744 	int err;
3745 	struct publication *p;
3746 
3747 	if (*last_publ) {
3748 		list_for_each_entry(p, &tsk->publications, binding_sock) {
3749 			if (p->key == *last_publ)
3750 				break;
3751 		}
3752 		if (list_entry_is_head(p, &tsk->publications, binding_sock)) {
3753 			/* We never set seq or call nl_dump_check_consistent()
3754 			 * this means that setting prev_seq here will cause the
3755 			 * consistence check to fail in the netlink callback
3756 			 * handler. Resulting in the last NLMSG_DONE message
3757 			 * having the NLM_F_DUMP_INTR flag set.
3758 			 */
3759 			cb->prev_seq = 1;
3760 			*last_publ = 0;
3761 			return -EPIPE;
3762 		}
3763 	} else {
3764 		p = list_first_entry(&tsk->publications, struct publication,
3765 				     binding_sock);
3766 	}
3767 
3768 	list_for_each_entry_from(p, &tsk->publications, binding_sock) {
3769 		err = __tipc_nl_add_sk_publ(skb, cb, p);
3770 		if (err) {
3771 			*last_publ = p->key;
3772 			return err;
3773 		}
3774 	}
3775 	*last_publ = 0;
3776 
3777 	return 0;
3778 }
3779 
3780 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
3781 {
3782 	int err;
3783 	u32 tsk_portid = cb->args[0];
3784 	u32 last_publ = cb->args[1];
3785 	u32 done = cb->args[2];
3786 	struct net *net = sock_net(skb->sk);
3787 	struct tipc_sock *tsk;
3788 
3789 	if (!tsk_portid) {
3790 		struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
3791 		struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
3792 
3793 		if (!attrs[TIPC_NLA_SOCK])
3794 			return -EINVAL;
3795 
3796 		err = nla_parse_nested_deprecated(sock, TIPC_NLA_SOCK_MAX,
3797 						  attrs[TIPC_NLA_SOCK],
3798 						  tipc_nl_sock_policy, NULL);
3799 		if (err)
3800 			return err;
3801 
3802 		if (!sock[TIPC_NLA_SOCK_REF])
3803 			return -EINVAL;
3804 
3805 		tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
3806 	}
3807 
3808 	if (done)
3809 		return 0;
3810 
3811 	tsk = tipc_sk_lookup(net, tsk_portid);
3812 	if (!tsk)
3813 		return -EINVAL;
3814 
3815 	lock_sock(&tsk->sk);
3816 	err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ);
3817 	if (!err)
3818 		done = 1;
3819 	release_sock(&tsk->sk);
3820 	sock_put(&tsk->sk);
3821 
3822 	cb->args[0] = tsk_portid;
3823 	cb->args[1] = last_publ;
3824 	cb->args[2] = done;
3825 
3826 	return skb->len;
3827 }
3828 
3829 /**
3830  * tipc_sk_filtering - check if a socket should be traced
3831  * @sk: the socket to be examined
3832  *
3833  * @sysctl_tipc_sk_filter is used as the socket tuple for filtering:
3834  * (portid, sock type, name type, name lower, name upper)
3835  *
3836  * Return: true if the socket meets the socket tuple data
3837  * (value 0 = 'any') or when there is no tuple set (all = 0),
3838  * otherwise false
3839  */
3840 bool tipc_sk_filtering(struct sock *sk)
3841 {
3842 	struct tipc_sock *tsk;
3843 	struct publication *p;
3844 	u32 _port, _sktype, _type, _lower, _upper;
3845 	u32 type = 0, lower = 0, upper = 0;
3846 
3847 	if (!sk)
3848 		return true;
3849 
3850 	tsk = tipc_sk(sk);
3851 
3852 	_port = sysctl_tipc_sk_filter[0];
3853 	_sktype = sysctl_tipc_sk_filter[1];
3854 	_type = sysctl_tipc_sk_filter[2];
3855 	_lower = sysctl_tipc_sk_filter[3];
3856 	_upper = sysctl_tipc_sk_filter[4];
3857 
3858 	if (!_port && !_sktype && !_type && !_lower && !_upper)
3859 		return true;
3860 
3861 	if (_port)
3862 		return (_port == tsk->portid);
3863 
3864 	if (_sktype && _sktype != sk->sk_type)
3865 		return false;
3866 
3867 	if (tsk->published) {
3868 		p = list_first_entry_or_null(&tsk->publications,
3869 					     struct publication, binding_sock);
3870 		if (p) {
3871 			type = p->sr.type;
3872 			lower = p->sr.lower;
3873 			upper = p->sr.upper;
3874 		}
3875 	}
3876 
3877 	if (!tipc_sk_type_connectionless(sk)) {
3878 		type = msg_nametype(&tsk->phdr);
3879 		lower = msg_nameinst(&tsk->phdr);
3880 		upper = lower;
3881 	}
3882 
3883 	if ((_type && _type != type) || (_lower && _lower != lower) ||
3884 	    (_upper && _upper != upper))
3885 		return false;
3886 
3887 	return true;
3888 }
3889 
3890 u32 tipc_sock_get_portid(struct sock *sk)
3891 {
3892 	return (sk) ? (tipc_sk(sk))->portid : 0;
3893 }
3894 
3895 /**
3896  * tipc_sk_overlimit1 - check if socket rx queue is about to be overloaded,
3897  *			both the rcv and backlog queues are considered
3898  * @sk: tipc sk to be checked
3899  * @skb: tipc msg to be checked
3900  *
3901  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3902  */
3903 
3904 bool tipc_sk_overlimit1(struct sock *sk, struct sk_buff *skb)
3905 {
3906 	atomic_t *dcnt = &tipc_sk(sk)->dupl_rcvcnt;
3907 	unsigned int lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
3908 	unsigned int qsize = sk->sk_backlog.len + sk_rmem_alloc_get(sk);
3909 
3910 	return (qsize > lim * 90 / 100);
3911 }
3912 
3913 /**
3914  * tipc_sk_overlimit2 - check if socket rx queue is about to be overloaded,
3915  *			only the rcv queue is considered
3916  * @sk: tipc sk to be checked
3917  * @skb: tipc msg to be checked
3918  *
3919  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3920  */
3921 
3922 bool tipc_sk_overlimit2(struct sock *sk, struct sk_buff *skb)
3923 {
3924 	unsigned int lim = rcvbuf_limit(sk, skb);
3925 	unsigned int qsize = sk_rmem_alloc_get(sk);
3926 
3927 	return (qsize > lim * 90 / 100);
3928 }
3929 
3930 /**
3931  * tipc_sk_dump - dump TIPC socket
3932  * @sk: tipc sk to be dumped
3933  * @dqueues: bitmask to decide if any socket queue to be dumped?
3934  *           - TIPC_DUMP_NONE: don't dump socket queues
3935  *           - TIPC_DUMP_SK_SNDQ: dump socket send queue
3936  *           - TIPC_DUMP_SK_RCVQ: dump socket rcv queue
3937  *           - TIPC_DUMP_SK_BKLGQ: dump socket backlog queue
3938  *           - TIPC_DUMP_ALL: dump all the socket queues above
3939  * @buf: returned buffer of dump data in format
3940  */
3941 int tipc_sk_dump(struct sock *sk, u16 dqueues, char *buf)
3942 {
3943 	int i = 0;
3944 	size_t sz = (dqueues) ? SK_LMAX : SK_LMIN;
3945 	u32 conn_type, conn_instance;
3946 	struct tipc_sock *tsk;
3947 	struct publication *p;
3948 	bool tsk_connected;
3949 
3950 	if (!sk) {
3951 		i += scnprintf(buf, sz, "sk data: (null)\n");
3952 		return i;
3953 	}
3954 
3955 	tsk = tipc_sk(sk);
3956 	tsk_connected = !tipc_sk_type_connectionless(sk);
3957 
3958 	i += scnprintf(buf, sz, "sk data: %u", sk->sk_type);
3959 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_state);
3960 	i += scnprintf(buf + i, sz - i, " %x", tsk_own_node(tsk));
3961 	i += scnprintf(buf + i, sz - i, " %u", tsk->portid);
3962 	i += scnprintf(buf + i, sz - i, " | %u", tsk_connected);
3963 	if (tsk_connected) {
3964 		i += scnprintf(buf + i, sz - i, " %x", tsk_peer_node(tsk));
3965 		i += scnprintf(buf + i, sz - i, " %u", tsk_peer_port(tsk));
3966 		conn_type = msg_nametype(&tsk->phdr);
3967 		conn_instance = msg_nameinst(&tsk->phdr);
3968 		i += scnprintf(buf + i, sz - i, " %u", conn_type);
3969 		i += scnprintf(buf + i, sz - i, " %u", conn_instance);
3970 	}
3971 	i += scnprintf(buf + i, sz - i, " | %u", tsk->published);
3972 	if (tsk->published) {
3973 		p = list_first_entry_or_null(&tsk->publications,
3974 					     struct publication, binding_sock);
3975 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.type : 0);
3976 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.lower : 0);
3977 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.upper : 0);
3978 	}
3979 	i += scnprintf(buf + i, sz - i, " | %u", tsk->snd_win);
3980 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_win);
3981 	i += scnprintf(buf + i, sz - i, " %u", tsk->max_pkt);
3982 	i += scnprintf(buf + i, sz - i, " %x", tsk->peer_caps);
3983 	i += scnprintf(buf + i, sz - i, " %u", tsk->cong_link_cnt);
3984 	i += scnprintf(buf + i, sz - i, " %u", tsk->snt_unacked);
3985 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_unacked);
3986 	i += scnprintf(buf + i, sz - i, " %u", atomic_read(&tsk->dupl_rcvcnt));
3987 	i += scnprintf(buf + i, sz - i, " %u", sk->sk_shutdown);
3988 	i += scnprintf(buf + i, sz - i, " | %d", sk_wmem_alloc_get(sk));
3989 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_sndbuf);
3990 	i += scnprintf(buf + i, sz - i, " | %d", sk_rmem_alloc_get(sk));
3991 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_rcvbuf);
3992 	i += scnprintf(buf + i, sz - i, " | %d\n", READ_ONCE(sk->sk_backlog.len));
3993 
3994 	if (dqueues & TIPC_DUMP_SK_SNDQ) {
3995 		i += scnprintf(buf + i, sz - i, "sk_write_queue: ");
3996 		i += tipc_list_dump(&sk->sk_write_queue, false, buf + i);
3997 	}
3998 
3999 	if (dqueues & TIPC_DUMP_SK_RCVQ) {
4000 		i += scnprintf(buf + i, sz - i, "sk_receive_queue: ");
4001 		i += tipc_list_dump(&sk->sk_receive_queue, false, buf + i);
4002 	}
4003 
4004 	if (dqueues & TIPC_DUMP_SK_BKLGQ) {
4005 		i += scnprintf(buf + i, sz - i, "sk_backlog:\n  head ");
4006 		i += tipc_skb_dump(sk->sk_backlog.head, false, buf + i);
4007 		if (sk->sk_backlog.tail != sk->sk_backlog.head) {
4008 			i += scnprintf(buf + i, sz - i, "  tail ");
4009 			i += tipc_skb_dump(sk->sk_backlog.tail, false,
4010 					   buf + i);
4011 		}
4012 	}
4013 
4014 	return i;
4015 }
4016