xref: /openbmc/linux/net/tipc/socket.c (revision c0891ac1)
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 
41 #include "core.h"
42 #include "name_table.h"
43 #include "node.h"
44 #include "link.h"
45 #include "name_distr.h"
46 #include "socket.h"
47 #include "bcast.h"
48 #include "netlink.h"
49 #include "group.h"
50 #include "trace.h"
51 
52 #define NAGLE_START_INIT	4
53 #define NAGLE_START_MAX		1024
54 #define CONN_TIMEOUT_DEFAULT    8000    /* default connect timeout = 8s */
55 #define CONN_PROBING_INTV	msecs_to_jiffies(3600000)  /* [ms] => 1 h */
56 #define TIPC_MAX_PORT		0xffffffff
57 #define TIPC_MIN_PORT		1
58 #define TIPC_ACK_RATE		4       /* ACK at 1/4 of rcv window size */
59 
60 enum {
61 	TIPC_LISTEN = TCP_LISTEN,
62 	TIPC_ESTABLISHED = TCP_ESTABLISHED,
63 	TIPC_OPEN = TCP_CLOSE,
64 	TIPC_DISCONNECTING = TCP_CLOSE_WAIT,
65 	TIPC_CONNECTING = TCP_SYN_SENT,
66 };
67 
68 struct sockaddr_pair {
69 	struct sockaddr_tipc sock;
70 	struct sockaddr_tipc member;
71 };
72 
73 /**
74  * struct tipc_sock - TIPC socket structure
75  * @sk: socket - interacts with 'port' and with user via the socket API
76  * @max_pkt: maximum packet size "hint" used when building messages sent by port
77  * @maxnagle: maximum size of msg which can be subject to nagle
78  * @portid: unique port identity in TIPC socket hash table
79  * @phdr: preformatted message header used when sending messages
80  * @cong_links: list of congested links
81  * @publications: list of publications for port
82  * @blocking_link: address of the congested link we are currently sleeping on
83  * @pub_count: total # of publications port has made during its lifetime
84  * @conn_timeout: the time we can wait for an unresponded setup request
85  * @probe_unacked: probe has not received ack yet
86  * @dupl_rcvcnt: number of bytes counted twice, in both backlog and rcv queue
87  * @cong_link_cnt: number of congested links
88  * @snt_unacked: # messages sent by socket, and not yet acked by peer
89  * @snd_win: send window size
90  * @peer_caps: peer capabilities mask
91  * @rcv_unacked: # messages read by user, but not yet acked back to peer
92  * @rcv_win: receive window size
93  * @peer: 'connected' peer for dgram/rdm
94  * @node: hash table node
95  * @mc_method: cookie for use between socket and broadcast layer
96  * @rcu: rcu struct for tipc_sock
97  * @group: TIPC communications group
98  * @oneway: message count in one direction (FIXME)
99  * @nagle_start: current nagle value
100  * @snd_backlog: send backlog count
101  * @msg_acc: messages accepted; used in managing backlog and nagle
102  * @pkt_cnt: TIPC socket packet count
103  * @expect_ack: whether this TIPC socket is expecting an ack
104  * @nodelay: setsockopt() TIPC_NODELAY setting
105  * @group_is_open: TIPC socket group is fully open (FIXME)
106  * @published: true if port has one or more associated names
107  * @conn_addrtype: address type used when establishing connection
108  */
109 struct tipc_sock {
110 	struct sock sk;
111 	u32 max_pkt;
112 	u32 maxnagle;
113 	u32 portid;
114 	struct tipc_msg phdr;
115 	struct list_head cong_links;
116 	struct list_head publications;
117 	u32 pub_count;
118 	atomic_t dupl_rcvcnt;
119 	u16 conn_timeout;
120 	bool probe_unacked;
121 	u16 cong_link_cnt;
122 	u16 snt_unacked;
123 	u16 snd_win;
124 	u16 peer_caps;
125 	u16 rcv_unacked;
126 	u16 rcv_win;
127 	struct sockaddr_tipc peer;
128 	struct rhash_head node;
129 	struct tipc_mc_method mc_method;
130 	struct rcu_head rcu;
131 	struct tipc_group *group;
132 	u32 oneway;
133 	u32 nagle_start;
134 	u16 snd_backlog;
135 	u16 msg_acc;
136 	u16 pkt_cnt;
137 	bool expect_ack;
138 	bool nodelay;
139 	bool group_is_open;
140 	bool published;
141 	u8 conn_addrtype;
142 };
143 
144 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
145 static void tipc_data_ready(struct sock *sk);
146 static void tipc_write_space(struct sock *sk);
147 static void tipc_sock_destruct(struct sock *sk);
148 static int tipc_release(struct socket *sock);
149 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
150 		       bool kern);
151 static void tipc_sk_timeout(struct timer_list *t);
152 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua);
153 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua);
154 static int tipc_sk_leave(struct tipc_sock *tsk);
155 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid);
156 static int tipc_sk_insert(struct tipc_sock *tsk);
157 static void tipc_sk_remove(struct tipc_sock *tsk);
158 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz);
159 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz);
160 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack);
161 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p);
162 
163 static const struct proto_ops packet_ops;
164 static const struct proto_ops stream_ops;
165 static const struct proto_ops msg_ops;
166 static struct proto tipc_proto;
167 static const struct rhashtable_params tsk_rht_params;
168 
169 static u32 tsk_own_node(struct tipc_sock *tsk)
170 {
171 	return msg_prevnode(&tsk->phdr);
172 }
173 
174 static u32 tsk_peer_node(struct tipc_sock *tsk)
175 {
176 	return msg_destnode(&tsk->phdr);
177 }
178 
179 static u32 tsk_peer_port(struct tipc_sock *tsk)
180 {
181 	return msg_destport(&tsk->phdr);
182 }
183 
184 static  bool tsk_unreliable(struct tipc_sock *tsk)
185 {
186 	return msg_src_droppable(&tsk->phdr) != 0;
187 }
188 
189 static void tsk_set_unreliable(struct tipc_sock *tsk, bool unreliable)
190 {
191 	msg_set_src_droppable(&tsk->phdr, unreliable ? 1 : 0);
192 }
193 
194 static bool tsk_unreturnable(struct tipc_sock *tsk)
195 {
196 	return msg_dest_droppable(&tsk->phdr) != 0;
197 }
198 
199 static void tsk_set_unreturnable(struct tipc_sock *tsk, bool unreturnable)
200 {
201 	msg_set_dest_droppable(&tsk->phdr, unreturnable ? 1 : 0);
202 }
203 
204 static int tsk_importance(struct tipc_sock *tsk)
205 {
206 	return msg_importance(&tsk->phdr);
207 }
208 
209 static struct tipc_sock *tipc_sk(const struct sock *sk)
210 {
211 	return container_of(sk, struct tipc_sock, sk);
212 }
213 
214 int tsk_set_importance(struct sock *sk, int imp)
215 {
216 	if (imp > TIPC_CRITICAL_IMPORTANCE)
217 		return -EINVAL;
218 	msg_set_importance(&tipc_sk(sk)->phdr, (u32)imp);
219 	return 0;
220 }
221 
222 static bool tsk_conn_cong(struct tipc_sock *tsk)
223 {
224 	return tsk->snt_unacked > tsk->snd_win;
225 }
226 
227 static u16 tsk_blocks(int len)
228 {
229 	return ((len / FLOWCTL_BLK_SZ) + 1);
230 }
231 
232 /* tsk_blocks(): translate a buffer size in bytes to number of
233  * advertisable blocks, taking into account the ratio truesize(len)/len
234  * We can trust that this ratio is always < 4 for len >= FLOWCTL_BLK_SZ
235  */
236 static u16 tsk_adv_blocks(int len)
237 {
238 	return len / FLOWCTL_BLK_SZ / 4;
239 }
240 
241 /* tsk_inc(): increment counter for sent or received data
242  * - If block based flow control is not supported by peer we
243  *   fall back to message based ditto, incrementing the counter
244  */
245 static u16 tsk_inc(struct tipc_sock *tsk, int msglen)
246 {
247 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
248 		return ((msglen / FLOWCTL_BLK_SZ) + 1);
249 	return 1;
250 }
251 
252 /* tsk_set_nagle - enable/disable nagle property by manipulating maxnagle
253  */
254 static void tsk_set_nagle(struct tipc_sock *tsk)
255 {
256 	struct sock *sk = &tsk->sk;
257 
258 	tsk->maxnagle = 0;
259 	if (sk->sk_type != SOCK_STREAM)
260 		return;
261 	if (tsk->nodelay)
262 		return;
263 	if (!(tsk->peer_caps & TIPC_NAGLE))
264 		return;
265 	/* Limit node local buffer size to avoid receive queue overflow */
266 	if (tsk->max_pkt == MAX_MSG_SIZE)
267 		tsk->maxnagle = 1500;
268 	else
269 		tsk->maxnagle = tsk->max_pkt;
270 }
271 
272 /**
273  * tsk_advance_rx_queue - discard first buffer in socket receive queue
274  * @sk: network socket
275  *
276  * Caller must hold socket lock
277  */
278 static void tsk_advance_rx_queue(struct sock *sk)
279 {
280 	trace_tipc_sk_advance_rx(sk, NULL, TIPC_DUMP_SK_RCVQ, " ");
281 	kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
282 }
283 
284 /* tipc_sk_respond() : send response message back to sender
285  */
286 static void tipc_sk_respond(struct sock *sk, struct sk_buff *skb, int err)
287 {
288 	u32 selector;
289 	u32 dnode;
290 	u32 onode = tipc_own_addr(sock_net(sk));
291 
292 	if (!tipc_msg_reverse(onode, &skb, err))
293 		return;
294 
295 	trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE, "@sk_respond!");
296 	dnode = msg_destnode(buf_msg(skb));
297 	selector = msg_origport(buf_msg(skb));
298 	tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector);
299 }
300 
301 /**
302  * tsk_rej_rx_queue - reject all buffers in socket receive queue
303  * @sk: network socket
304  * @error: response error code
305  *
306  * Caller must hold socket lock
307  */
308 static void tsk_rej_rx_queue(struct sock *sk, int error)
309 {
310 	struct sk_buff *skb;
311 
312 	while ((skb = __skb_dequeue(&sk->sk_receive_queue)))
313 		tipc_sk_respond(sk, skb, error);
314 }
315 
316 static bool tipc_sk_connected(struct sock *sk)
317 {
318 	return sk->sk_state == TIPC_ESTABLISHED;
319 }
320 
321 /* tipc_sk_type_connectionless - check if the socket is datagram socket
322  * @sk: socket
323  *
324  * Returns true if connection less, false otherwise
325  */
326 static bool tipc_sk_type_connectionless(struct sock *sk)
327 {
328 	return sk->sk_type == SOCK_RDM || sk->sk_type == SOCK_DGRAM;
329 }
330 
331 /* tsk_peer_msg - verify if message was sent by connected port's peer
332  *
333  * Handles cases where the node's network address has changed from
334  * the default of <0.0.0> to its configured setting.
335  */
336 static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg)
337 {
338 	struct sock *sk = &tsk->sk;
339 	u32 self = tipc_own_addr(sock_net(sk));
340 	u32 peer_port = tsk_peer_port(tsk);
341 	u32 orig_node, peer_node;
342 
343 	if (unlikely(!tipc_sk_connected(sk)))
344 		return false;
345 
346 	if (unlikely(msg_origport(msg) != peer_port))
347 		return false;
348 
349 	orig_node = msg_orignode(msg);
350 	peer_node = tsk_peer_node(tsk);
351 
352 	if (likely(orig_node == peer_node))
353 		return true;
354 
355 	if (!orig_node && peer_node == self)
356 		return true;
357 
358 	if (!peer_node && orig_node == self)
359 		return true;
360 
361 	return false;
362 }
363 
364 /* tipc_set_sk_state - set the sk_state of the socket
365  * @sk: socket
366  *
367  * Caller must hold socket lock
368  *
369  * Returns 0 on success, errno otherwise
370  */
371 static int tipc_set_sk_state(struct sock *sk, int state)
372 {
373 	int oldsk_state = sk->sk_state;
374 	int res = -EINVAL;
375 
376 	switch (state) {
377 	case TIPC_OPEN:
378 		res = 0;
379 		break;
380 	case TIPC_LISTEN:
381 	case TIPC_CONNECTING:
382 		if (oldsk_state == TIPC_OPEN)
383 			res = 0;
384 		break;
385 	case TIPC_ESTABLISHED:
386 		if (oldsk_state == TIPC_CONNECTING ||
387 		    oldsk_state == TIPC_OPEN)
388 			res = 0;
389 		break;
390 	case TIPC_DISCONNECTING:
391 		if (oldsk_state == TIPC_CONNECTING ||
392 		    oldsk_state == TIPC_ESTABLISHED)
393 			res = 0;
394 		break;
395 	}
396 
397 	if (!res)
398 		sk->sk_state = state;
399 
400 	return res;
401 }
402 
403 static int tipc_sk_sock_err(struct socket *sock, long *timeout)
404 {
405 	struct sock *sk = sock->sk;
406 	int err = sock_error(sk);
407 	int typ = sock->type;
408 
409 	if (err)
410 		return err;
411 	if (typ == SOCK_STREAM || typ == SOCK_SEQPACKET) {
412 		if (sk->sk_state == TIPC_DISCONNECTING)
413 			return -EPIPE;
414 		else if (!tipc_sk_connected(sk))
415 			return -ENOTCONN;
416 	}
417 	if (!*timeout)
418 		return -EAGAIN;
419 	if (signal_pending(current))
420 		return sock_intr_errno(*timeout);
421 
422 	return 0;
423 }
424 
425 #define tipc_wait_for_cond(sock_, timeo_, condition_)			       \
426 ({                                                                             \
427 	DEFINE_WAIT_FUNC(wait_, woken_wake_function);                          \
428 	struct sock *sk_;						       \
429 	int rc_;							       \
430 									       \
431 	while ((rc_ = !(condition_))) {					       \
432 		/* coupled with smp_wmb() in tipc_sk_proto_rcv() */            \
433 		smp_rmb();                                                     \
434 		sk_ = (sock_)->sk;					       \
435 		rc_ = tipc_sk_sock_err((sock_), timeo_);		       \
436 		if (rc_)						       \
437 			break;						       \
438 		add_wait_queue(sk_sleep(sk_), &wait_);                         \
439 		release_sock(sk_);					       \
440 		*(timeo_) = wait_woken(&wait_, TASK_INTERRUPTIBLE, *(timeo_)); \
441 		sched_annotate_sleep();				               \
442 		lock_sock(sk_);						       \
443 		remove_wait_queue(sk_sleep(sk_), &wait_);		       \
444 	}								       \
445 	rc_;								       \
446 })
447 
448 /**
449  * tipc_sk_create - create a TIPC socket
450  * @net: network namespace (must be default network)
451  * @sock: pre-allocated socket structure
452  * @protocol: protocol indicator (must be 0)
453  * @kern: caused by kernel or by userspace?
454  *
455  * This routine creates additional data structures used by the TIPC socket,
456  * initializes them, and links them together.
457  *
458  * Return: 0 on success, errno otherwise
459  */
460 static int tipc_sk_create(struct net *net, struct socket *sock,
461 			  int protocol, int kern)
462 {
463 	const struct proto_ops *ops;
464 	struct sock *sk;
465 	struct tipc_sock *tsk;
466 	struct tipc_msg *msg;
467 
468 	/* Validate arguments */
469 	if (unlikely(protocol != 0))
470 		return -EPROTONOSUPPORT;
471 
472 	switch (sock->type) {
473 	case SOCK_STREAM:
474 		ops = &stream_ops;
475 		break;
476 	case SOCK_SEQPACKET:
477 		ops = &packet_ops;
478 		break;
479 	case SOCK_DGRAM:
480 	case SOCK_RDM:
481 		ops = &msg_ops;
482 		break;
483 	default:
484 		return -EPROTOTYPE;
485 	}
486 
487 	/* Allocate socket's protocol area */
488 	sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto, kern);
489 	if (sk == NULL)
490 		return -ENOMEM;
491 
492 	tsk = tipc_sk(sk);
493 	tsk->max_pkt = MAX_PKT_DEFAULT;
494 	tsk->maxnagle = 0;
495 	tsk->nagle_start = NAGLE_START_INIT;
496 	INIT_LIST_HEAD(&tsk->publications);
497 	INIT_LIST_HEAD(&tsk->cong_links);
498 	msg = &tsk->phdr;
499 
500 	/* Finish initializing socket data structures */
501 	sock->ops = ops;
502 	sock_init_data(sock, sk);
503 	tipc_set_sk_state(sk, TIPC_OPEN);
504 	if (tipc_sk_insert(tsk)) {
505 		pr_warn("Socket create failed; port number exhausted\n");
506 		return -EINVAL;
507 	}
508 
509 	/* Ensure tsk is visible before we read own_addr. */
510 	smp_mb();
511 
512 	tipc_msg_init(tipc_own_addr(net), msg, TIPC_LOW_IMPORTANCE,
513 		      TIPC_NAMED_MSG, NAMED_H_SIZE, 0);
514 
515 	msg_set_origport(msg, tsk->portid);
516 	timer_setup(&sk->sk_timer, tipc_sk_timeout, 0);
517 	sk->sk_shutdown = 0;
518 	sk->sk_backlog_rcv = tipc_sk_backlog_rcv;
519 	sk->sk_rcvbuf = sysctl_tipc_rmem[1];
520 	sk->sk_data_ready = tipc_data_ready;
521 	sk->sk_write_space = tipc_write_space;
522 	sk->sk_destruct = tipc_sock_destruct;
523 	tsk->conn_timeout = CONN_TIMEOUT_DEFAULT;
524 	tsk->group_is_open = true;
525 	atomic_set(&tsk->dupl_rcvcnt, 0);
526 
527 	/* Start out with safe limits until we receive an advertised window */
528 	tsk->snd_win = tsk_adv_blocks(RCVBUF_MIN);
529 	tsk->rcv_win = tsk->snd_win;
530 
531 	if (tipc_sk_type_connectionless(sk)) {
532 		tsk_set_unreturnable(tsk, true);
533 		if (sock->type == SOCK_DGRAM)
534 			tsk_set_unreliable(tsk, true);
535 	}
536 	__skb_queue_head_init(&tsk->mc_method.deferredq);
537 	trace_tipc_sk_create(sk, NULL, TIPC_DUMP_NONE, " ");
538 	return 0;
539 }
540 
541 static void tipc_sk_callback(struct rcu_head *head)
542 {
543 	struct tipc_sock *tsk = container_of(head, struct tipc_sock, rcu);
544 
545 	sock_put(&tsk->sk);
546 }
547 
548 /* Caller should hold socket lock for the socket. */
549 static void __tipc_shutdown(struct socket *sock, int error)
550 {
551 	struct sock *sk = sock->sk;
552 	struct tipc_sock *tsk = tipc_sk(sk);
553 	struct net *net = sock_net(sk);
554 	long timeout = msecs_to_jiffies(CONN_TIMEOUT_DEFAULT);
555 	u32 dnode = tsk_peer_node(tsk);
556 	struct sk_buff *skb;
557 
558 	/* Avoid that hi-prio shutdown msgs bypass msgs in link wakeup queue */
559 	tipc_wait_for_cond(sock, &timeout, (!tsk->cong_link_cnt &&
560 					    !tsk_conn_cong(tsk)));
561 
562 	/* Push out delayed messages if in Nagle mode */
563 	tipc_sk_push_backlog(tsk, false);
564 	/* Remove pending SYN */
565 	__skb_queue_purge(&sk->sk_write_queue);
566 
567 	/* Remove partially received buffer if any */
568 	skb = skb_peek(&sk->sk_receive_queue);
569 	if (skb && TIPC_SKB_CB(skb)->bytes_read) {
570 		__skb_unlink(skb, &sk->sk_receive_queue);
571 		kfree_skb(skb);
572 	}
573 
574 	/* Reject all unreceived messages if connectionless */
575 	if (tipc_sk_type_connectionless(sk)) {
576 		tsk_rej_rx_queue(sk, error);
577 		return;
578 	}
579 
580 	switch (sk->sk_state) {
581 	case TIPC_CONNECTING:
582 	case TIPC_ESTABLISHED:
583 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
584 		tipc_node_remove_conn(net, dnode, tsk->portid);
585 		/* Send a FIN+/- to its peer */
586 		skb = __skb_dequeue(&sk->sk_receive_queue);
587 		if (skb) {
588 			__skb_queue_purge(&sk->sk_receive_queue);
589 			tipc_sk_respond(sk, skb, error);
590 			break;
591 		}
592 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
593 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode,
594 				      tsk_own_node(tsk), tsk_peer_port(tsk),
595 				      tsk->portid, error);
596 		if (skb)
597 			tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
598 		break;
599 	case TIPC_LISTEN:
600 		/* Reject all SYN messages */
601 		tsk_rej_rx_queue(sk, error);
602 		break;
603 	default:
604 		__skb_queue_purge(&sk->sk_receive_queue);
605 		break;
606 	}
607 }
608 
609 /**
610  * tipc_release - destroy a TIPC socket
611  * @sock: socket to destroy
612  *
613  * This routine cleans up any messages that are still queued on the socket.
614  * For DGRAM and RDM socket types, all queued messages are rejected.
615  * For SEQPACKET and STREAM socket types, the first message is rejected
616  * and any others are discarded.  (If the first message on a STREAM socket
617  * is partially-read, it is discarded and the next one is rejected instead.)
618  *
619  * NOTE: Rejected messages are not necessarily returned to the sender!  They
620  * are returned or discarded according to the "destination droppable" setting
621  * specified for the message by the sender.
622  *
623  * Return: 0 on success, errno otherwise
624  */
625 static int tipc_release(struct socket *sock)
626 {
627 	struct sock *sk = sock->sk;
628 	struct tipc_sock *tsk;
629 
630 	/*
631 	 * Exit if socket isn't fully initialized (occurs when a failed accept()
632 	 * releases a pre-allocated child socket that was never used)
633 	 */
634 	if (sk == NULL)
635 		return 0;
636 
637 	tsk = tipc_sk(sk);
638 	lock_sock(sk);
639 
640 	trace_tipc_sk_release(sk, NULL, TIPC_DUMP_ALL, " ");
641 	__tipc_shutdown(sock, TIPC_ERR_NO_PORT);
642 	sk->sk_shutdown = SHUTDOWN_MASK;
643 	tipc_sk_leave(tsk);
644 	tipc_sk_withdraw(tsk, NULL);
645 	__skb_queue_purge(&tsk->mc_method.deferredq);
646 	sk_stop_timer(sk, &sk->sk_timer);
647 	tipc_sk_remove(tsk);
648 
649 	sock_orphan(sk);
650 	/* Reject any messages that accumulated in backlog queue */
651 	release_sock(sk);
652 	tipc_dest_list_purge(&tsk->cong_links);
653 	tsk->cong_link_cnt = 0;
654 	call_rcu(&tsk->rcu, tipc_sk_callback);
655 	sock->sk = NULL;
656 
657 	return 0;
658 }
659 
660 /**
661  * __tipc_bind - associate or disassocate TIPC name(s) with a socket
662  * @sock: socket structure
663  * @skaddr: socket address describing name(s) and desired operation
664  * @alen: size of socket address data structure
665  *
666  * Name and name sequence binding are indicated using a positive scope value;
667  * a negative scope value unbinds the specified name.  Specifying no name
668  * (i.e. a socket address length of 0) unbinds all names from the socket.
669  *
670  * Return: 0 on success, errno otherwise
671  *
672  * NOTE: This routine doesn't need to take the socket lock since it doesn't
673  *       access any non-constant socket information.
674  */
675 static int __tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
676 {
677 	struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr;
678 	struct tipc_sock *tsk = tipc_sk(sock->sk);
679 	bool unbind = false;
680 
681 	if (unlikely(!alen))
682 		return tipc_sk_withdraw(tsk, NULL);
683 
684 	if (ua->addrtype == TIPC_SERVICE_ADDR) {
685 		ua->addrtype = TIPC_SERVICE_RANGE;
686 		ua->sr.upper = ua->sr.lower;
687 	}
688 	if (ua->scope < 0) {
689 		unbind = true;
690 		ua->scope = -ua->scope;
691 	}
692 	/* Users may still use deprecated TIPC_ZONE_SCOPE */
693 	if (ua->scope != TIPC_NODE_SCOPE)
694 		ua->scope = TIPC_CLUSTER_SCOPE;
695 
696 	if (tsk->group)
697 		return -EACCES;
698 
699 	if (unbind)
700 		return tipc_sk_withdraw(tsk, ua);
701 	return tipc_sk_publish(tsk, ua);
702 }
703 
704 int tipc_sk_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
705 {
706 	int res;
707 
708 	lock_sock(sock->sk);
709 	res = __tipc_bind(sock, skaddr, alen);
710 	release_sock(sock->sk);
711 	return res;
712 }
713 
714 static int tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
715 {
716 	struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr;
717 	u32 atype = ua->addrtype;
718 
719 	if (alen) {
720 		if (!tipc_uaddr_valid(ua, alen))
721 			return -EINVAL;
722 		if (atype == TIPC_SOCKET_ADDR)
723 			return -EAFNOSUPPORT;
724 		if (ua->sr.type < TIPC_RESERVED_TYPES) {
725 			pr_warn_once("Can't bind to reserved service type %u\n",
726 				     ua->sr.type);
727 			return -EACCES;
728 		}
729 	}
730 	return tipc_sk_bind(sock, skaddr, alen);
731 }
732 
733 /**
734  * tipc_getname - get port ID of socket or peer socket
735  * @sock: socket structure
736  * @uaddr: area for returned socket address
737  * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
738  *
739  * Return: 0 on success, errno otherwise
740  *
741  * NOTE: This routine doesn't need to take the socket lock since it only
742  *       accesses socket information that is unchanging (or which changes in
743  *       a completely predictable manner).
744  */
745 static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
746 			int peer)
747 {
748 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
749 	struct sock *sk = sock->sk;
750 	struct tipc_sock *tsk = tipc_sk(sk);
751 
752 	memset(addr, 0, sizeof(*addr));
753 	if (peer) {
754 		if ((!tipc_sk_connected(sk)) &&
755 		    ((peer != 2) || (sk->sk_state != TIPC_DISCONNECTING)))
756 			return -ENOTCONN;
757 		addr->addr.id.ref = tsk_peer_port(tsk);
758 		addr->addr.id.node = tsk_peer_node(tsk);
759 	} else {
760 		addr->addr.id.ref = tsk->portid;
761 		addr->addr.id.node = tipc_own_addr(sock_net(sk));
762 	}
763 
764 	addr->addrtype = TIPC_SOCKET_ADDR;
765 	addr->family = AF_TIPC;
766 	addr->scope = 0;
767 	addr->addr.name.domain = 0;
768 
769 	return sizeof(*addr);
770 }
771 
772 /**
773  * tipc_poll - read and possibly block on pollmask
774  * @file: file structure associated with the socket
775  * @sock: socket for which to calculate the poll bits
776  * @wait: ???
777  *
778  * Return: pollmask value
779  *
780  * COMMENTARY:
781  * It appears that the usual socket locking mechanisms are not useful here
782  * since the pollmask info is potentially out-of-date the moment this routine
783  * exits.  TCP and other protocols seem to rely on higher level poll routines
784  * to handle any preventable race conditions, so TIPC will do the same ...
785  *
786  * IMPORTANT: The fact that a read or write operation is indicated does NOT
787  * imply that the operation will succeed, merely that it should be performed
788  * and will not block.
789  */
790 static __poll_t tipc_poll(struct file *file, struct socket *sock,
791 			      poll_table *wait)
792 {
793 	struct sock *sk = sock->sk;
794 	struct tipc_sock *tsk = tipc_sk(sk);
795 	__poll_t revents = 0;
796 
797 	sock_poll_wait(file, sock, wait);
798 	trace_tipc_sk_poll(sk, NULL, TIPC_DUMP_ALL, " ");
799 
800 	if (sk->sk_shutdown & RCV_SHUTDOWN)
801 		revents |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
802 	if (sk->sk_shutdown == SHUTDOWN_MASK)
803 		revents |= EPOLLHUP;
804 
805 	switch (sk->sk_state) {
806 	case TIPC_ESTABLISHED:
807 		if (!tsk->cong_link_cnt && !tsk_conn_cong(tsk))
808 			revents |= EPOLLOUT;
809 		fallthrough;
810 	case TIPC_LISTEN:
811 	case TIPC_CONNECTING:
812 		if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
813 			revents |= EPOLLIN | EPOLLRDNORM;
814 		break;
815 	case TIPC_OPEN:
816 		if (tsk->group_is_open && !tsk->cong_link_cnt)
817 			revents |= EPOLLOUT;
818 		if (!tipc_sk_type_connectionless(sk))
819 			break;
820 		if (skb_queue_empty_lockless(&sk->sk_receive_queue))
821 			break;
822 		revents |= EPOLLIN | EPOLLRDNORM;
823 		break;
824 	case TIPC_DISCONNECTING:
825 		revents = EPOLLIN | EPOLLRDNORM | EPOLLHUP;
826 		break;
827 	}
828 	return revents;
829 }
830 
831 /**
832  * tipc_sendmcast - send multicast message
833  * @sock: socket structure
834  * @ua: destination address struct
835  * @msg: message to send
836  * @dlen: length of data to send
837  * @timeout: timeout to wait for wakeup
838  *
839  * Called from function tipc_sendmsg(), which has done all sanity checks
840  * Return: the number of bytes sent on success, or errno
841  */
842 static int tipc_sendmcast(struct  socket *sock, struct tipc_uaddr *ua,
843 			  struct msghdr *msg, size_t dlen, long timeout)
844 {
845 	struct sock *sk = sock->sk;
846 	struct tipc_sock *tsk = tipc_sk(sk);
847 	struct tipc_msg *hdr = &tsk->phdr;
848 	struct net *net = sock_net(sk);
849 	int mtu = tipc_bcast_get_mtu(net);
850 	struct sk_buff_head pkts;
851 	struct tipc_nlist dsts;
852 	int rc;
853 
854 	if (tsk->group)
855 		return -EACCES;
856 
857 	/* Block or return if any destination link is congested */
858 	rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt);
859 	if (unlikely(rc))
860 		return rc;
861 
862 	/* Lookup destination nodes */
863 	tipc_nlist_init(&dsts, tipc_own_addr(net));
864 	tipc_nametbl_lookup_mcast_nodes(net, ua, &dsts);
865 	if (!dsts.local && !dsts.remote)
866 		return -EHOSTUNREACH;
867 
868 	/* Build message header */
869 	msg_set_type(hdr, TIPC_MCAST_MSG);
870 	msg_set_hdr_sz(hdr, MCAST_H_SIZE);
871 	msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE);
872 	msg_set_destport(hdr, 0);
873 	msg_set_destnode(hdr, 0);
874 	msg_set_nametype(hdr, ua->sr.type);
875 	msg_set_namelower(hdr, ua->sr.lower);
876 	msg_set_nameupper(hdr, ua->sr.upper);
877 
878 	/* Build message as chain of buffers */
879 	__skb_queue_head_init(&pkts);
880 	rc = tipc_msg_build(hdr, msg, 0, dlen, mtu, &pkts);
881 
882 	/* Send message if build was successful */
883 	if (unlikely(rc == dlen)) {
884 		trace_tipc_sk_sendmcast(sk, skb_peek(&pkts),
885 					TIPC_DUMP_SK_SNDQ, " ");
886 		rc = tipc_mcast_xmit(net, &pkts, &tsk->mc_method, &dsts,
887 				     &tsk->cong_link_cnt);
888 	}
889 
890 	tipc_nlist_purge(&dsts);
891 
892 	return rc ? rc : dlen;
893 }
894 
895 /**
896  * tipc_send_group_msg - send a message to a member in the group
897  * @net: network namespace
898  * @tsk: tipc socket
899  * @m: message to send
900  * @mb: group member
901  * @dnode: destination node
902  * @dport: destination port
903  * @dlen: total length of message data
904  */
905 static int tipc_send_group_msg(struct net *net, struct tipc_sock *tsk,
906 			       struct msghdr *m, struct tipc_member *mb,
907 			       u32 dnode, u32 dport, int dlen)
908 {
909 	u16 bc_snd_nxt = tipc_group_bc_snd_nxt(tsk->group);
910 	struct tipc_mc_method *method = &tsk->mc_method;
911 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
912 	struct tipc_msg *hdr = &tsk->phdr;
913 	struct sk_buff_head pkts;
914 	int mtu, rc;
915 
916 	/* Complete message header */
917 	msg_set_type(hdr, TIPC_GRP_UCAST_MSG);
918 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
919 	msg_set_destport(hdr, dport);
920 	msg_set_destnode(hdr, dnode);
921 	msg_set_grp_bc_seqno(hdr, bc_snd_nxt);
922 
923 	/* Build message as chain of buffers */
924 	__skb_queue_head_init(&pkts);
925 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid, false);
926 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
927 	if (unlikely(rc != dlen))
928 		return rc;
929 
930 	/* Send message */
931 	rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
932 	if (unlikely(rc == -ELINKCONG)) {
933 		tipc_dest_push(&tsk->cong_links, dnode, 0);
934 		tsk->cong_link_cnt++;
935 	}
936 
937 	/* Update send window */
938 	tipc_group_update_member(mb, blks);
939 
940 	/* A broadcast sent within next EXPIRE period must follow same path */
941 	method->rcast = true;
942 	method->mandatory = true;
943 	return dlen;
944 }
945 
946 /**
947  * tipc_send_group_unicast - send message to a member in the group
948  * @sock: socket structure
949  * @m: message to send
950  * @dlen: total length of message data
951  * @timeout: timeout to wait for wakeup
952  *
953  * Called from function tipc_sendmsg(), which has done all sanity checks
954  * Return: the number of bytes sent on success, or errno
955  */
956 static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m,
957 				   int dlen, long timeout)
958 {
959 	struct sock *sk = sock->sk;
960 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
961 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
962 	struct tipc_sock *tsk = tipc_sk(sk);
963 	struct net *net = sock_net(sk);
964 	struct tipc_member *mb = NULL;
965 	u32 node, port;
966 	int rc;
967 
968 	node = ua->sk.node;
969 	port = ua->sk.ref;
970 	if (!port && !node)
971 		return -EHOSTUNREACH;
972 
973 	/* Block or return if destination link or member is congested */
974 	rc = tipc_wait_for_cond(sock, &timeout,
975 				!tipc_dest_find(&tsk->cong_links, node, 0) &&
976 				tsk->group &&
977 				!tipc_group_cong(tsk->group, node, port, blks,
978 						 &mb));
979 	if (unlikely(rc))
980 		return rc;
981 
982 	if (unlikely(!mb))
983 		return -EHOSTUNREACH;
984 
985 	rc = tipc_send_group_msg(net, tsk, m, mb, node, port, dlen);
986 
987 	return rc ? rc : dlen;
988 }
989 
990 /**
991  * tipc_send_group_anycast - send message to any member with given identity
992  * @sock: socket structure
993  * @m: message to send
994  * @dlen: total length of message data
995  * @timeout: timeout to wait for wakeup
996  *
997  * Called from function tipc_sendmsg(), which has done all sanity checks
998  * Return: the number of bytes sent on success, or errno
999  */
1000 static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
1001 				   int dlen, long timeout)
1002 {
1003 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1004 	struct sock *sk = sock->sk;
1005 	struct tipc_sock *tsk = tipc_sk(sk);
1006 	struct list_head *cong_links = &tsk->cong_links;
1007 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
1008 	struct tipc_msg *hdr = &tsk->phdr;
1009 	struct tipc_member *first = NULL;
1010 	struct tipc_member *mbr = NULL;
1011 	struct net *net = sock_net(sk);
1012 	u32 node, port, exclude;
1013 	struct list_head dsts;
1014 	int lookups = 0;
1015 	int dstcnt, rc;
1016 	bool cong;
1017 
1018 	INIT_LIST_HEAD(&dsts);
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 	struct list_head dsts;
1166 	u32 dstcnt, exclude;
1167 
1168 	INIT_LIST_HEAD(&dsts);
1169 	ua->sa.type = msg_nametype(hdr);
1170 	ua->scope = msg_lookup_scope(hdr);
1171 	exclude = tipc_group_exclude(grp);
1172 
1173 	if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt, exclude, true))
1174 		return -EHOSTUNREACH;
1175 
1176 	if (dstcnt == 1) {
1177 		tipc_dest_pop(&dsts, &ua->sk.node, &ua->sk.ref);
1178 		return tipc_send_group_unicast(sock, m, dlen, timeout);
1179 	}
1180 
1181 	tipc_dest_list_purge(&dsts);
1182 	return tipc_send_group_bcast(sock, m, dlen, timeout);
1183 }
1184 
1185 /**
1186  * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets
1187  * @net: the associated network namespace
1188  * @arrvq: queue with arriving messages, to be cloned after destination lookup
1189  * @inputq: queue with cloned messages, delivered to socket after dest lookup
1190  *
1191  * Multi-threaded: parallel calls with reference to same queues may occur
1192  */
1193 void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
1194 		       struct sk_buff_head *inputq)
1195 {
1196 	u32 self = tipc_own_addr(net);
1197 	struct sk_buff *skb, *_skb;
1198 	u32 portid, onode;
1199 	struct sk_buff_head tmpq;
1200 	struct list_head dports;
1201 	struct tipc_msg *hdr;
1202 	struct tipc_uaddr ua;
1203 	int user, mtyp, hlen;
1204 
1205 	__skb_queue_head_init(&tmpq);
1206 	INIT_LIST_HEAD(&dports);
1207 	ua.addrtype = TIPC_SERVICE_RANGE;
1208 
1209 	/* tipc_skb_peek() increments the head skb's reference counter */
1210 	skb = tipc_skb_peek(arrvq, &inputq->lock);
1211 	for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) {
1212 		hdr = buf_msg(skb);
1213 		user = msg_user(hdr);
1214 		mtyp = msg_type(hdr);
1215 		hlen = skb_headroom(skb) + msg_hdr_sz(hdr);
1216 		onode = msg_orignode(hdr);
1217 		ua.sr.type = msg_nametype(hdr);
1218 		ua.sr.lower = msg_namelower(hdr);
1219 		ua.sr.upper = msg_nameupper(hdr);
1220 		if (onode == self)
1221 			ua.scope = TIPC_ANY_SCOPE;
1222 		else
1223 			ua.scope = TIPC_CLUSTER_SCOPE;
1224 
1225 		if (mtyp == TIPC_GRP_UCAST_MSG || user == GROUP_PROTOCOL) {
1226 			spin_lock_bh(&inputq->lock);
1227 			if (skb_peek(arrvq) == skb) {
1228 				__skb_dequeue(arrvq);
1229 				__skb_queue_tail(inputq, skb);
1230 			}
1231 			kfree_skb(skb);
1232 			spin_unlock_bh(&inputq->lock);
1233 			continue;
1234 		}
1235 
1236 		/* Group messages require exact scope match */
1237 		if (msg_in_group(hdr)) {
1238 			ua.sr.lower = 0;
1239 			ua.sr.upper = ~0;
1240 			ua.scope = msg_lookup_scope(hdr);
1241 		}
1242 
1243 		/* Create destination port list: */
1244 		tipc_nametbl_lookup_mcast_sockets(net, &ua, &dports);
1245 
1246 		/* Clone message per destination */
1247 		while (tipc_dest_pop(&dports, NULL, &portid)) {
1248 			_skb = __pskb_copy(skb, hlen, GFP_ATOMIC);
1249 			if (_skb) {
1250 				msg_set_destport(buf_msg(_skb), portid);
1251 				__skb_queue_tail(&tmpq, _skb);
1252 				continue;
1253 			}
1254 			pr_warn("Failed to clone mcast rcv buffer\n");
1255 		}
1256 		/* Append clones to inputq only if skb is still head of arrvq */
1257 		spin_lock_bh(&inputq->lock);
1258 		if (skb_peek(arrvq) == skb) {
1259 			skb_queue_splice_tail_init(&tmpq, inputq);
1260 			/* Decrement the skb's refcnt */
1261 			kfree_skb(__skb_dequeue(arrvq));
1262 		}
1263 		spin_unlock_bh(&inputq->lock);
1264 		__skb_queue_purge(&tmpq);
1265 		kfree_skb(skb);
1266 	}
1267 	tipc_sk_rcv(net, inputq);
1268 }
1269 
1270 /* tipc_sk_push_backlog(): send accumulated buffers in socket write queue
1271  *                         when socket is in Nagle mode
1272  */
1273 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack)
1274 {
1275 	struct sk_buff_head *txq = &tsk->sk.sk_write_queue;
1276 	struct sk_buff *skb = skb_peek_tail(txq);
1277 	struct net *net = sock_net(&tsk->sk);
1278 	u32 dnode = tsk_peer_node(tsk);
1279 	int rc;
1280 
1281 	if (nagle_ack) {
1282 		tsk->pkt_cnt += skb_queue_len(txq);
1283 		if (!tsk->pkt_cnt || tsk->msg_acc / tsk->pkt_cnt < 2) {
1284 			tsk->oneway = 0;
1285 			if (tsk->nagle_start < NAGLE_START_MAX)
1286 				tsk->nagle_start *= 2;
1287 			tsk->expect_ack = false;
1288 			pr_debug("tsk %10u: bad nagle %u -> %u, next start %u!\n",
1289 				 tsk->portid, tsk->msg_acc, tsk->pkt_cnt,
1290 				 tsk->nagle_start);
1291 		} else {
1292 			tsk->nagle_start = NAGLE_START_INIT;
1293 			if (skb) {
1294 				msg_set_ack_required(buf_msg(skb));
1295 				tsk->expect_ack = true;
1296 			} else {
1297 				tsk->expect_ack = false;
1298 			}
1299 		}
1300 		tsk->msg_acc = 0;
1301 		tsk->pkt_cnt = 0;
1302 	}
1303 
1304 	if (!skb || tsk->cong_link_cnt)
1305 		return;
1306 
1307 	/* Do not send SYN again after congestion */
1308 	if (msg_is_syn(buf_msg(skb)))
1309 		return;
1310 
1311 	if (tsk->msg_acc)
1312 		tsk->pkt_cnt += skb_queue_len(txq);
1313 	tsk->snt_unacked += tsk->snd_backlog;
1314 	tsk->snd_backlog = 0;
1315 	rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1316 	if (rc == -ELINKCONG)
1317 		tsk->cong_link_cnt = 1;
1318 }
1319 
1320 /**
1321  * tipc_sk_conn_proto_rcv - receive a connection mng protocol message
1322  * @tsk: receiving socket
1323  * @skb: pointer to message buffer.
1324  * @inputq: buffer list containing the buffers
1325  * @xmitq: output message area
1326  */
1327 static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb,
1328 				   struct sk_buff_head *inputq,
1329 				   struct sk_buff_head *xmitq)
1330 {
1331 	struct tipc_msg *hdr = buf_msg(skb);
1332 	u32 onode = tsk_own_node(tsk);
1333 	struct sock *sk = &tsk->sk;
1334 	int mtyp = msg_type(hdr);
1335 	bool was_cong;
1336 
1337 	/* Ignore if connection cannot be validated: */
1338 	if (!tsk_peer_msg(tsk, hdr)) {
1339 		trace_tipc_sk_drop_msg(sk, skb, TIPC_DUMP_NONE, "@proto_rcv!");
1340 		goto exit;
1341 	}
1342 
1343 	if (unlikely(msg_errcode(hdr))) {
1344 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1345 		tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
1346 				      tsk_peer_port(tsk));
1347 		sk->sk_state_change(sk);
1348 
1349 		/* State change is ignored if socket already awake,
1350 		 * - convert msg to abort msg and add to inqueue
1351 		 */
1352 		msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE);
1353 		msg_set_type(hdr, TIPC_CONN_MSG);
1354 		msg_set_size(hdr, BASIC_H_SIZE);
1355 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1356 		__skb_queue_tail(inputq, skb);
1357 		return;
1358 	}
1359 
1360 	tsk->probe_unacked = false;
1361 
1362 	if (mtyp == CONN_PROBE) {
1363 		msg_set_type(hdr, CONN_PROBE_REPLY);
1364 		if (tipc_msg_reverse(onode, &skb, TIPC_OK))
1365 			__skb_queue_tail(xmitq, skb);
1366 		return;
1367 	} else if (mtyp == CONN_ACK) {
1368 		was_cong = tsk_conn_cong(tsk);
1369 		tipc_sk_push_backlog(tsk, msg_nagle_ack(hdr));
1370 		tsk->snt_unacked -= msg_conn_ack(hdr);
1371 		if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1372 			tsk->snd_win = msg_adv_win(hdr);
1373 		if (was_cong && !tsk_conn_cong(tsk))
1374 			sk->sk_write_space(sk);
1375 	} else if (mtyp != CONN_PROBE_REPLY) {
1376 		pr_warn("Received unknown CONN_PROTO msg\n");
1377 	}
1378 exit:
1379 	kfree_skb(skb);
1380 }
1381 
1382 /**
1383  * tipc_sendmsg - send message in connectionless manner
1384  * @sock: socket structure
1385  * @m: message to send
1386  * @dsz: amount of user data to be sent
1387  *
1388  * Message must have an destination specified explicitly.
1389  * Used for SOCK_RDM and SOCK_DGRAM messages,
1390  * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
1391  * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
1392  *
1393  * Return: the number of bytes sent on success, or errno otherwise
1394  */
1395 static int tipc_sendmsg(struct socket *sock,
1396 			struct msghdr *m, size_t dsz)
1397 {
1398 	struct sock *sk = sock->sk;
1399 	int ret;
1400 
1401 	lock_sock(sk);
1402 	ret = __tipc_sendmsg(sock, m, dsz);
1403 	release_sock(sk);
1404 
1405 	return ret;
1406 }
1407 
1408 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
1409 {
1410 	struct sock *sk = sock->sk;
1411 	struct net *net = sock_net(sk);
1412 	struct tipc_sock *tsk = tipc_sk(sk);
1413 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1414 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1415 	struct list_head *clinks = &tsk->cong_links;
1416 	bool syn = !tipc_sk_type_connectionless(sk);
1417 	struct tipc_group *grp = tsk->group;
1418 	struct tipc_msg *hdr = &tsk->phdr;
1419 	struct tipc_socket_addr skaddr;
1420 	struct sk_buff_head pkts;
1421 	int atype, mtu, rc;
1422 
1423 	if (unlikely(dlen > TIPC_MAX_USER_MSG_SIZE))
1424 		return -EMSGSIZE;
1425 
1426 	if (ua) {
1427 		if (!tipc_uaddr_valid(ua, m->msg_namelen))
1428 			return -EINVAL;
1429 		 atype = ua->addrtype;
1430 	}
1431 
1432 	/* If socket belongs to a communication group follow other paths */
1433 	if (grp) {
1434 		if (!ua)
1435 			return tipc_send_group_bcast(sock, m, dlen, timeout);
1436 		if (atype == TIPC_SERVICE_ADDR)
1437 			return tipc_send_group_anycast(sock, m, dlen, timeout);
1438 		if (atype == TIPC_SOCKET_ADDR)
1439 			return tipc_send_group_unicast(sock, m, dlen, timeout);
1440 		if (atype == TIPC_SERVICE_RANGE)
1441 			return tipc_send_group_mcast(sock, m, dlen, timeout);
1442 		return -EINVAL;
1443 	}
1444 
1445 	if (!ua) {
1446 		ua = (struct tipc_uaddr *)&tsk->peer;
1447 		if (!syn && ua->family != AF_TIPC)
1448 			return -EDESTADDRREQ;
1449 		atype = ua->addrtype;
1450 	}
1451 
1452 	if (unlikely(syn)) {
1453 		if (sk->sk_state == TIPC_LISTEN)
1454 			return -EPIPE;
1455 		if (sk->sk_state != TIPC_OPEN)
1456 			return -EISCONN;
1457 		if (tsk->published)
1458 			return -EOPNOTSUPP;
1459 		if (atype == TIPC_SERVICE_ADDR)
1460 			tsk->conn_addrtype = atype;
1461 		msg_set_syn(hdr, 1);
1462 	}
1463 
1464 	/* Determine destination */
1465 	if (atype == TIPC_SERVICE_RANGE) {
1466 		return tipc_sendmcast(sock, ua, m, dlen, timeout);
1467 	} else if (atype == TIPC_SERVICE_ADDR) {
1468 		skaddr.node = ua->lookup_node;
1469 		ua->scope = tipc_node2scope(skaddr.node);
1470 		if (!tipc_nametbl_lookup_anycast(net, ua, &skaddr))
1471 			return -EHOSTUNREACH;
1472 	} else if (atype == TIPC_SOCKET_ADDR) {
1473 		skaddr = ua->sk;
1474 	} else {
1475 		return -EINVAL;
1476 	}
1477 
1478 	/* Block or return if destination link is congested */
1479 	rc = tipc_wait_for_cond(sock, &timeout,
1480 				!tipc_dest_find(clinks, skaddr.node, 0));
1481 	if (unlikely(rc))
1482 		return rc;
1483 
1484 	/* Finally build message header */
1485 	msg_set_destnode(hdr, skaddr.node);
1486 	msg_set_destport(hdr, skaddr.ref);
1487 	if (atype == TIPC_SERVICE_ADDR) {
1488 		msg_set_type(hdr, TIPC_NAMED_MSG);
1489 		msg_set_hdr_sz(hdr, NAMED_H_SIZE);
1490 		msg_set_nametype(hdr, ua->sa.type);
1491 		msg_set_nameinst(hdr, ua->sa.instance);
1492 		msg_set_lookup_scope(hdr, ua->scope);
1493 	} else { /* TIPC_SOCKET_ADDR */
1494 		msg_set_type(hdr, TIPC_DIRECT_MSG);
1495 		msg_set_lookup_scope(hdr, 0);
1496 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1497 	}
1498 
1499 	/* Add message body */
1500 	__skb_queue_head_init(&pkts);
1501 	mtu = tipc_node_get_mtu(net, skaddr.node, tsk->portid, true);
1502 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1503 	if (unlikely(rc != dlen))
1504 		return rc;
1505 	if (unlikely(syn && !tipc_msg_skb_clone(&pkts, &sk->sk_write_queue))) {
1506 		__skb_queue_purge(&pkts);
1507 		return -ENOMEM;
1508 	}
1509 
1510 	/* Send message */
1511 	trace_tipc_sk_sendmsg(sk, skb_peek(&pkts), TIPC_DUMP_SK_SNDQ, " ");
1512 	rc = tipc_node_xmit(net, &pkts, skaddr.node, tsk->portid);
1513 	if (unlikely(rc == -ELINKCONG)) {
1514 		tipc_dest_push(clinks, skaddr.node, 0);
1515 		tsk->cong_link_cnt++;
1516 		rc = 0;
1517 	}
1518 
1519 	if (unlikely(syn && !rc)) {
1520 		tipc_set_sk_state(sk, TIPC_CONNECTING);
1521 		if (timeout) {
1522 			timeout = msecs_to_jiffies(timeout);
1523 			tipc_wait_for_connect(sock, &timeout);
1524 		}
1525 	}
1526 
1527 	return rc ? rc : dlen;
1528 }
1529 
1530 /**
1531  * tipc_sendstream - send stream-oriented data
1532  * @sock: socket structure
1533  * @m: data to send
1534  * @dsz: total length of data to be transmitted
1535  *
1536  * Used for SOCK_STREAM data.
1537  *
1538  * Return: the number of bytes sent on success (or partial success),
1539  * or errno if no data sent
1540  */
1541 static int tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz)
1542 {
1543 	struct sock *sk = sock->sk;
1544 	int ret;
1545 
1546 	lock_sock(sk);
1547 	ret = __tipc_sendstream(sock, m, dsz);
1548 	release_sock(sk);
1549 
1550 	return ret;
1551 }
1552 
1553 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dlen)
1554 {
1555 	struct sock *sk = sock->sk;
1556 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1557 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1558 	struct sk_buff_head *txq = &sk->sk_write_queue;
1559 	struct tipc_sock *tsk = tipc_sk(sk);
1560 	struct tipc_msg *hdr = &tsk->phdr;
1561 	struct net *net = sock_net(sk);
1562 	struct sk_buff *skb;
1563 	u32 dnode = tsk_peer_node(tsk);
1564 	int maxnagle = tsk->maxnagle;
1565 	int maxpkt = tsk->max_pkt;
1566 	int send, sent = 0;
1567 	int blocks, rc = 0;
1568 
1569 	if (unlikely(dlen > INT_MAX))
1570 		return -EMSGSIZE;
1571 
1572 	/* Handle implicit connection setup */
1573 	if (unlikely(dest && sk->sk_state == TIPC_OPEN)) {
1574 		rc = __tipc_sendmsg(sock, m, dlen);
1575 		if (dlen && dlen == rc) {
1576 			tsk->peer_caps = tipc_node_get_capabilities(net, dnode);
1577 			tsk->snt_unacked = tsk_inc(tsk, dlen + msg_hdr_sz(hdr));
1578 		}
1579 		return rc;
1580 	}
1581 
1582 	do {
1583 		rc = tipc_wait_for_cond(sock, &timeout,
1584 					(!tsk->cong_link_cnt &&
1585 					 !tsk_conn_cong(tsk) &&
1586 					 tipc_sk_connected(sk)));
1587 		if (unlikely(rc))
1588 			break;
1589 		send = min_t(size_t, dlen - sent, TIPC_MAX_USER_MSG_SIZE);
1590 		blocks = tsk->snd_backlog;
1591 		if (tsk->oneway++ >= tsk->nagle_start && maxnagle &&
1592 		    send <= maxnagle) {
1593 			rc = tipc_msg_append(hdr, m, send, maxnagle, txq);
1594 			if (unlikely(rc < 0))
1595 				break;
1596 			blocks += rc;
1597 			tsk->msg_acc++;
1598 			if (blocks <= 64 && tsk->expect_ack) {
1599 				tsk->snd_backlog = blocks;
1600 				sent += send;
1601 				break;
1602 			} else if (blocks > 64) {
1603 				tsk->pkt_cnt += skb_queue_len(txq);
1604 			} else {
1605 				skb = skb_peek_tail(txq);
1606 				if (skb) {
1607 					msg_set_ack_required(buf_msg(skb));
1608 					tsk->expect_ack = true;
1609 				} else {
1610 					tsk->expect_ack = false;
1611 				}
1612 				tsk->msg_acc = 0;
1613 				tsk->pkt_cnt = 0;
1614 			}
1615 		} else {
1616 			rc = tipc_msg_build(hdr, m, sent, send, maxpkt, txq);
1617 			if (unlikely(rc != send))
1618 				break;
1619 			blocks += tsk_inc(tsk, send + MIN_H_SIZE);
1620 		}
1621 		trace_tipc_sk_sendstream(sk, skb_peek(txq),
1622 					 TIPC_DUMP_SK_SNDQ, " ");
1623 		rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1624 		if (unlikely(rc == -ELINKCONG)) {
1625 			tsk->cong_link_cnt = 1;
1626 			rc = 0;
1627 		}
1628 		if (likely(!rc)) {
1629 			tsk->snt_unacked += blocks;
1630 			tsk->snd_backlog = 0;
1631 			sent += send;
1632 		}
1633 	} while (sent < dlen && !rc);
1634 
1635 	return sent ? sent : rc;
1636 }
1637 
1638 /**
1639  * tipc_send_packet - send a connection-oriented message
1640  * @sock: socket structure
1641  * @m: message to send
1642  * @dsz: length of data to be transmitted
1643  *
1644  * Used for SOCK_SEQPACKET messages.
1645  *
1646  * Return: the number of bytes sent on success, or errno otherwise
1647  */
1648 static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz)
1649 {
1650 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
1651 		return -EMSGSIZE;
1652 
1653 	return tipc_sendstream(sock, m, dsz);
1654 }
1655 
1656 /* tipc_sk_finish_conn - complete the setup of a connection
1657  */
1658 static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port,
1659 				u32 peer_node)
1660 {
1661 	struct sock *sk = &tsk->sk;
1662 	struct net *net = sock_net(sk);
1663 	struct tipc_msg *msg = &tsk->phdr;
1664 
1665 	msg_set_syn(msg, 0);
1666 	msg_set_destnode(msg, peer_node);
1667 	msg_set_destport(msg, peer_port);
1668 	msg_set_type(msg, TIPC_CONN_MSG);
1669 	msg_set_lookup_scope(msg, 0);
1670 	msg_set_hdr_sz(msg, SHORT_H_SIZE);
1671 
1672 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
1673 	tipc_set_sk_state(sk, TIPC_ESTABLISHED);
1674 	tipc_node_add_conn(net, peer_node, tsk->portid, peer_port);
1675 	tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid, true);
1676 	tsk->peer_caps = tipc_node_get_capabilities(net, peer_node);
1677 	tsk_set_nagle(tsk);
1678 	__skb_queue_purge(&sk->sk_write_queue);
1679 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1680 		return;
1681 
1682 	/* Fall back to message based flow control */
1683 	tsk->rcv_win = FLOWCTL_MSG_WIN;
1684 	tsk->snd_win = FLOWCTL_MSG_WIN;
1685 }
1686 
1687 /**
1688  * tipc_sk_set_orig_addr - capture sender's address for received message
1689  * @m: descriptor for message info
1690  * @skb: received message
1691  *
1692  * Note: Address is not captured if not requested by receiver.
1693  */
1694 static void tipc_sk_set_orig_addr(struct msghdr *m, struct sk_buff *skb)
1695 {
1696 	DECLARE_SOCKADDR(struct sockaddr_pair *, srcaddr, m->msg_name);
1697 	struct tipc_msg *hdr = buf_msg(skb);
1698 
1699 	if (!srcaddr)
1700 		return;
1701 
1702 	srcaddr->sock.family = AF_TIPC;
1703 	srcaddr->sock.addrtype = TIPC_SOCKET_ADDR;
1704 	srcaddr->sock.scope = 0;
1705 	srcaddr->sock.addr.id.ref = msg_origport(hdr);
1706 	srcaddr->sock.addr.id.node = msg_orignode(hdr);
1707 	srcaddr->sock.addr.name.domain = 0;
1708 	m->msg_namelen = sizeof(struct sockaddr_tipc);
1709 
1710 	if (!msg_in_group(hdr))
1711 		return;
1712 
1713 	/* Group message users may also want to know sending member's id */
1714 	srcaddr->member.family = AF_TIPC;
1715 	srcaddr->member.addrtype = TIPC_SERVICE_ADDR;
1716 	srcaddr->member.scope = 0;
1717 	srcaddr->member.addr.name.name.type = msg_nametype(hdr);
1718 	srcaddr->member.addr.name.name.instance = TIPC_SKB_CB(skb)->orig_member;
1719 	srcaddr->member.addr.name.domain = 0;
1720 	m->msg_namelen = sizeof(*srcaddr);
1721 }
1722 
1723 /**
1724  * tipc_sk_anc_data_recv - optionally capture ancillary data for received message
1725  * @m: descriptor for message info
1726  * @skb: received message buffer
1727  * @tsk: TIPC port associated with message
1728  *
1729  * Note: Ancillary data is not captured if not requested by receiver.
1730  *
1731  * Return: 0 if successful, otherwise errno
1732  */
1733 static int tipc_sk_anc_data_recv(struct msghdr *m, struct sk_buff *skb,
1734 				 struct tipc_sock *tsk)
1735 {
1736 	struct tipc_msg *hdr;
1737 	u32 data[3] = {0,};
1738 	bool has_addr;
1739 	int dlen, rc;
1740 
1741 	if (likely(m->msg_controllen == 0))
1742 		return 0;
1743 
1744 	hdr = buf_msg(skb);
1745 	dlen = msg_data_sz(hdr);
1746 
1747 	/* Capture errored message object, if any */
1748 	if (msg_errcode(hdr)) {
1749 		if (skb_linearize(skb))
1750 			return -ENOMEM;
1751 		hdr = buf_msg(skb);
1752 		data[0] = msg_errcode(hdr);
1753 		data[1] = dlen;
1754 		rc = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, data);
1755 		if (rc || !dlen)
1756 			return rc;
1757 		rc = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, dlen, msg_data(hdr));
1758 		if (rc)
1759 			return rc;
1760 	}
1761 
1762 	/* Capture TIPC_SERVICE_ADDR/RANGE destination address, if any */
1763 	switch (msg_type(hdr)) {
1764 	case TIPC_NAMED_MSG:
1765 		has_addr = true;
1766 		data[0] = msg_nametype(hdr);
1767 		data[1] = msg_namelower(hdr);
1768 		data[2] = data[1];
1769 		break;
1770 	case TIPC_MCAST_MSG:
1771 		has_addr = true;
1772 		data[0] = msg_nametype(hdr);
1773 		data[1] = msg_namelower(hdr);
1774 		data[2] = msg_nameupper(hdr);
1775 		break;
1776 	case TIPC_CONN_MSG:
1777 		has_addr = !!tsk->conn_addrtype;
1778 		data[0] = msg_nametype(&tsk->phdr);
1779 		data[1] = msg_nameinst(&tsk->phdr);
1780 		data[2] = data[1];
1781 		break;
1782 	default:
1783 		has_addr = false;
1784 	}
1785 	if (!has_addr)
1786 		return 0;
1787 	return put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, data);
1788 }
1789 
1790 static struct sk_buff *tipc_sk_build_ack(struct tipc_sock *tsk)
1791 {
1792 	struct sock *sk = &tsk->sk;
1793 	struct sk_buff *skb = NULL;
1794 	struct tipc_msg *msg;
1795 	u32 peer_port = tsk_peer_port(tsk);
1796 	u32 dnode = tsk_peer_node(tsk);
1797 
1798 	if (!tipc_sk_connected(sk))
1799 		return NULL;
1800 	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
1801 			      dnode, tsk_own_node(tsk), peer_port,
1802 			      tsk->portid, TIPC_OK);
1803 	if (!skb)
1804 		return NULL;
1805 	msg = buf_msg(skb);
1806 	msg_set_conn_ack(msg, tsk->rcv_unacked);
1807 	tsk->rcv_unacked = 0;
1808 
1809 	/* Adjust to and advertize the correct window limit */
1810 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) {
1811 		tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf);
1812 		msg_set_adv_win(msg, tsk->rcv_win);
1813 	}
1814 	return skb;
1815 }
1816 
1817 static void tipc_sk_send_ack(struct tipc_sock *tsk)
1818 {
1819 	struct sk_buff *skb;
1820 
1821 	skb = tipc_sk_build_ack(tsk);
1822 	if (!skb)
1823 		return;
1824 
1825 	tipc_node_xmit_skb(sock_net(&tsk->sk), skb, tsk_peer_node(tsk),
1826 			   msg_link_selector(buf_msg(skb)));
1827 }
1828 
1829 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
1830 {
1831 	struct sock *sk = sock->sk;
1832 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1833 	long timeo = *timeop;
1834 	int err = sock_error(sk);
1835 
1836 	if (err)
1837 		return err;
1838 
1839 	for (;;) {
1840 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1841 			if (sk->sk_shutdown & RCV_SHUTDOWN) {
1842 				err = -ENOTCONN;
1843 				break;
1844 			}
1845 			add_wait_queue(sk_sleep(sk), &wait);
1846 			release_sock(sk);
1847 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
1848 			sched_annotate_sleep();
1849 			lock_sock(sk);
1850 			remove_wait_queue(sk_sleep(sk), &wait);
1851 		}
1852 		err = 0;
1853 		if (!skb_queue_empty(&sk->sk_receive_queue))
1854 			break;
1855 		err = -EAGAIN;
1856 		if (!timeo)
1857 			break;
1858 		err = sock_intr_errno(timeo);
1859 		if (signal_pending(current))
1860 			break;
1861 
1862 		err = sock_error(sk);
1863 		if (err)
1864 			break;
1865 	}
1866 	*timeop = timeo;
1867 	return err;
1868 }
1869 
1870 /**
1871  * tipc_recvmsg - receive packet-oriented message
1872  * @sock: network socket
1873  * @m: descriptor for message info
1874  * @buflen: length of user buffer area
1875  * @flags: receive flags
1876  *
1877  * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1878  * If the complete message doesn't fit in user area, truncate it.
1879  *
1880  * Return: size of returned message data, errno otherwise
1881  */
1882 static int tipc_recvmsg(struct socket *sock, struct msghdr *m,
1883 			size_t buflen,	int flags)
1884 {
1885 	struct sock *sk = sock->sk;
1886 	bool connected = !tipc_sk_type_connectionless(sk);
1887 	struct tipc_sock *tsk = tipc_sk(sk);
1888 	int rc, err, hlen, dlen, copy;
1889 	struct sk_buff_head xmitq;
1890 	struct tipc_msg *hdr;
1891 	struct sk_buff *skb;
1892 	bool grp_evt;
1893 	long timeout;
1894 
1895 	/* Catch invalid receive requests */
1896 	if (unlikely(!buflen))
1897 		return -EINVAL;
1898 
1899 	lock_sock(sk);
1900 	if (unlikely(connected && sk->sk_state == TIPC_OPEN)) {
1901 		rc = -ENOTCONN;
1902 		goto exit;
1903 	}
1904 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1905 
1906 	/* Step rcv queue to first msg with data or error; wait if necessary */
1907 	do {
1908 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
1909 		if (unlikely(rc))
1910 			goto exit;
1911 		skb = skb_peek(&sk->sk_receive_queue);
1912 		hdr = buf_msg(skb);
1913 		dlen = msg_data_sz(hdr);
1914 		hlen = msg_hdr_sz(hdr);
1915 		err = msg_errcode(hdr);
1916 		grp_evt = msg_is_grp_evt(hdr);
1917 		if (likely(dlen || err))
1918 			break;
1919 		tsk_advance_rx_queue(sk);
1920 	} while (1);
1921 
1922 	/* Collect msg meta data, including error code and rejected data */
1923 	tipc_sk_set_orig_addr(m, skb);
1924 	rc = tipc_sk_anc_data_recv(m, skb, tsk);
1925 	if (unlikely(rc))
1926 		goto exit;
1927 	hdr = buf_msg(skb);
1928 
1929 	/* Capture data if non-error msg, otherwise just set return value */
1930 	if (likely(!err)) {
1931 		copy = min_t(int, dlen, buflen);
1932 		if (unlikely(copy != dlen))
1933 			m->msg_flags |= MSG_TRUNC;
1934 		rc = skb_copy_datagram_msg(skb, hlen, m, copy);
1935 	} else {
1936 		copy = 0;
1937 		rc = 0;
1938 		if (err != TIPC_CONN_SHUTDOWN && connected && !m->msg_control)
1939 			rc = -ECONNRESET;
1940 	}
1941 	if (unlikely(rc))
1942 		goto exit;
1943 
1944 	/* Mark message as group event if applicable */
1945 	if (unlikely(grp_evt)) {
1946 		if (msg_grp_evt(hdr) == TIPC_WITHDRAWN)
1947 			m->msg_flags |= MSG_EOR;
1948 		m->msg_flags |= MSG_OOB;
1949 		copy = 0;
1950 	}
1951 
1952 	/* Caption of data or error code/rejected data was successful */
1953 	if (unlikely(flags & MSG_PEEK))
1954 		goto exit;
1955 
1956 	/* Send group flow control advertisement when applicable */
1957 	if (tsk->group && msg_in_group(hdr) && !grp_evt) {
1958 		__skb_queue_head_init(&xmitq);
1959 		tipc_group_update_rcv_win(tsk->group, tsk_blocks(hlen + dlen),
1960 					  msg_orignode(hdr), msg_origport(hdr),
1961 					  &xmitq);
1962 		tipc_node_distr_xmit(sock_net(sk), &xmitq);
1963 	}
1964 
1965 	tsk_advance_rx_queue(sk);
1966 
1967 	if (likely(!connected))
1968 		goto exit;
1969 
1970 	/* Send connection flow control advertisement when applicable */
1971 	tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
1972 	if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
1973 		tipc_sk_send_ack(tsk);
1974 exit:
1975 	release_sock(sk);
1976 	return rc ? rc : copy;
1977 }
1978 
1979 /**
1980  * tipc_recvstream - receive stream-oriented data
1981  * @sock: network socket
1982  * @m: descriptor for message info
1983  * @buflen: total size of user buffer area
1984  * @flags: receive flags
1985  *
1986  * Used for SOCK_STREAM messages only.  If not enough data is available
1987  * will optionally wait for more; never truncates data.
1988  *
1989  * Return: size of returned message data, errno otherwise
1990  */
1991 static int tipc_recvstream(struct socket *sock, struct msghdr *m,
1992 			   size_t buflen, int flags)
1993 {
1994 	struct sock *sk = sock->sk;
1995 	struct tipc_sock *tsk = tipc_sk(sk);
1996 	struct sk_buff *skb;
1997 	struct tipc_msg *hdr;
1998 	struct tipc_skb_cb *skb_cb;
1999 	bool peek = flags & MSG_PEEK;
2000 	int offset, required, copy, copied = 0;
2001 	int hlen, dlen, err, rc;
2002 	long timeout;
2003 
2004 	/* Catch invalid receive attempts */
2005 	if (unlikely(!buflen))
2006 		return -EINVAL;
2007 
2008 	lock_sock(sk);
2009 
2010 	if (unlikely(sk->sk_state == TIPC_OPEN)) {
2011 		rc = -ENOTCONN;
2012 		goto exit;
2013 	}
2014 	required = sock_rcvlowat(sk, flags & MSG_WAITALL, buflen);
2015 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
2016 
2017 	do {
2018 		/* Look at first msg in receive queue; wait if necessary */
2019 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
2020 		if (unlikely(rc))
2021 			break;
2022 		skb = skb_peek(&sk->sk_receive_queue);
2023 		skb_cb = TIPC_SKB_CB(skb);
2024 		hdr = buf_msg(skb);
2025 		dlen = msg_data_sz(hdr);
2026 		hlen = msg_hdr_sz(hdr);
2027 		err = msg_errcode(hdr);
2028 
2029 		/* Discard any empty non-errored (SYN-) message */
2030 		if (unlikely(!dlen && !err)) {
2031 			tsk_advance_rx_queue(sk);
2032 			continue;
2033 		}
2034 
2035 		/* Collect msg meta data, incl. error code and rejected data */
2036 		if (!copied) {
2037 			tipc_sk_set_orig_addr(m, skb);
2038 			rc = tipc_sk_anc_data_recv(m, skb, tsk);
2039 			if (rc)
2040 				break;
2041 			hdr = buf_msg(skb);
2042 		}
2043 
2044 		/* Copy data if msg ok, otherwise return error/partial data */
2045 		if (likely(!err)) {
2046 			offset = skb_cb->bytes_read;
2047 			copy = min_t(int, dlen - offset, buflen - copied);
2048 			rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
2049 			if (unlikely(rc))
2050 				break;
2051 			copied += copy;
2052 			offset += copy;
2053 			if (unlikely(offset < dlen)) {
2054 				if (!peek)
2055 					skb_cb->bytes_read = offset;
2056 				break;
2057 			}
2058 		} else {
2059 			rc = 0;
2060 			if ((err != TIPC_CONN_SHUTDOWN) && !m->msg_control)
2061 				rc = -ECONNRESET;
2062 			if (copied || rc)
2063 				break;
2064 		}
2065 
2066 		if (unlikely(peek))
2067 			break;
2068 
2069 		tsk_advance_rx_queue(sk);
2070 
2071 		/* Send connection flow control advertisement when applicable */
2072 		tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
2073 		if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
2074 			tipc_sk_send_ack(tsk);
2075 
2076 		/* Exit if all requested data or FIN/error received */
2077 		if (copied == buflen || err)
2078 			break;
2079 
2080 	} while (!skb_queue_empty(&sk->sk_receive_queue) || copied < required);
2081 exit:
2082 	release_sock(sk);
2083 	return copied ? copied : rc;
2084 }
2085 
2086 /**
2087  * tipc_write_space - wake up thread if port congestion is released
2088  * @sk: socket
2089  */
2090 static void tipc_write_space(struct sock *sk)
2091 {
2092 	struct socket_wq *wq;
2093 
2094 	rcu_read_lock();
2095 	wq = rcu_dereference(sk->sk_wq);
2096 	if (skwq_has_sleeper(wq))
2097 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2098 						EPOLLWRNORM | EPOLLWRBAND);
2099 	rcu_read_unlock();
2100 }
2101 
2102 /**
2103  * tipc_data_ready - wake up threads to indicate messages have been received
2104  * @sk: socket
2105  */
2106 static void tipc_data_ready(struct sock *sk)
2107 {
2108 	struct socket_wq *wq;
2109 
2110 	rcu_read_lock();
2111 	wq = rcu_dereference(sk->sk_wq);
2112 	if (skwq_has_sleeper(wq))
2113 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
2114 						EPOLLRDNORM | EPOLLRDBAND);
2115 	rcu_read_unlock();
2116 }
2117 
2118 static void tipc_sock_destruct(struct sock *sk)
2119 {
2120 	__skb_queue_purge(&sk->sk_receive_queue);
2121 }
2122 
2123 static void tipc_sk_proto_rcv(struct sock *sk,
2124 			      struct sk_buff_head *inputq,
2125 			      struct sk_buff_head *xmitq)
2126 {
2127 	struct sk_buff *skb = __skb_dequeue(inputq);
2128 	struct tipc_sock *tsk = tipc_sk(sk);
2129 	struct tipc_msg *hdr = buf_msg(skb);
2130 	struct tipc_group *grp = tsk->group;
2131 	bool wakeup = false;
2132 
2133 	switch (msg_user(hdr)) {
2134 	case CONN_MANAGER:
2135 		tipc_sk_conn_proto_rcv(tsk, skb, inputq, xmitq);
2136 		return;
2137 	case SOCK_WAKEUP:
2138 		tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0);
2139 		/* coupled with smp_rmb() in tipc_wait_for_cond() */
2140 		smp_wmb();
2141 		tsk->cong_link_cnt--;
2142 		wakeup = true;
2143 		tipc_sk_push_backlog(tsk, false);
2144 		break;
2145 	case GROUP_PROTOCOL:
2146 		tipc_group_proto_rcv(grp, &wakeup, hdr, inputq, xmitq);
2147 		break;
2148 	case TOP_SRV:
2149 		tipc_group_member_evt(tsk->group, &wakeup, &sk->sk_rcvbuf,
2150 				      hdr, inputq, xmitq);
2151 		break;
2152 	default:
2153 		break;
2154 	}
2155 
2156 	if (wakeup)
2157 		sk->sk_write_space(sk);
2158 
2159 	kfree_skb(skb);
2160 }
2161 
2162 /**
2163  * tipc_sk_filter_connect - check incoming message for a connection-based socket
2164  * @tsk: TIPC socket
2165  * @skb: pointer to message buffer.
2166  * @xmitq: for Nagle ACK if any
2167  * Return: true if message should be added to receive queue, false otherwise
2168  */
2169 static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb,
2170 				   struct sk_buff_head *xmitq)
2171 {
2172 	struct sock *sk = &tsk->sk;
2173 	struct net *net = sock_net(sk);
2174 	struct tipc_msg *hdr = buf_msg(skb);
2175 	bool con_msg = msg_connected(hdr);
2176 	u32 pport = tsk_peer_port(tsk);
2177 	u32 pnode = tsk_peer_node(tsk);
2178 	u32 oport = msg_origport(hdr);
2179 	u32 onode = msg_orignode(hdr);
2180 	int err = msg_errcode(hdr);
2181 	unsigned long delay;
2182 
2183 	if (unlikely(msg_mcast(hdr)))
2184 		return false;
2185 	tsk->oneway = 0;
2186 
2187 	switch (sk->sk_state) {
2188 	case TIPC_CONNECTING:
2189 		/* Setup ACK */
2190 		if (likely(con_msg)) {
2191 			if (err)
2192 				break;
2193 			tipc_sk_finish_conn(tsk, oport, onode);
2194 			msg_set_importance(&tsk->phdr, msg_importance(hdr));
2195 			/* ACK+ message with data is added to receive queue */
2196 			if (msg_data_sz(hdr))
2197 				return true;
2198 			/* Empty ACK-, - wake up sleeping connect() and drop */
2199 			sk->sk_state_change(sk);
2200 			msg_set_dest_droppable(hdr, 1);
2201 			return false;
2202 		}
2203 		/* Ignore connectionless message if not from listening socket */
2204 		if (oport != pport || onode != pnode)
2205 			return false;
2206 
2207 		/* Rejected SYN */
2208 		if (err != TIPC_ERR_OVERLOAD)
2209 			break;
2210 
2211 		/* Prepare for new setup attempt if we have a SYN clone */
2212 		if (skb_queue_empty(&sk->sk_write_queue))
2213 			break;
2214 		get_random_bytes(&delay, 2);
2215 		delay %= (tsk->conn_timeout / 4);
2216 		delay = msecs_to_jiffies(delay + 100);
2217 		sk_reset_timer(sk, &sk->sk_timer, jiffies + delay);
2218 		return false;
2219 	case TIPC_OPEN:
2220 	case TIPC_DISCONNECTING:
2221 		return false;
2222 	case TIPC_LISTEN:
2223 		/* Accept only SYN message */
2224 		if (!msg_is_syn(hdr) &&
2225 		    tipc_node_get_capabilities(net, onode) & TIPC_SYN_BIT)
2226 			return false;
2227 		if (!con_msg && !err)
2228 			return true;
2229 		return false;
2230 	case TIPC_ESTABLISHED:
2231 		if (!skb_queue_empty(&sk->sk_write_queue))
2232 			tipc_sk_push_backlog(tsk, false);
2233 		/* Accept only connection-based messages sent by peer */
2234 		if (likely(con_msg && !err && pport == oport &&
2235 			   pnode == onode)) {
2236 			if (msg_ack_required(hdr)) {
2237 				struct sk_buff *skb;
2238 
2239 				skb = tipc_sk_build_ack(tsk);
2240 				if (skb) {
2241 					msg_set_nagle_ack(buf_msg(skb));
2242 					__skb_queue_tail(xmitq, skb);
2243 				}
2244 			}
2245 			return true;
2246 		}
2247 		if (!tsk_peer_msg(tsk, hdr))
2248 			return false;
2249 		if (!err)
2250 			return true;
2251 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2252 		tipc_node_remove_conn(net, pnode, tsk->portid);
2253 		sk->sk_state_change(sk);
2254 		return true;
2255 	default:
2256 		pr_err("Unknown sk_state %u\n", sk->sk_state);
2257 	}
2258 	/* Abort connection setup attempt */
2259 	tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2260 	sk->sk_err = ECONNREFUSED;
2261 	sk->sk_state_change(sk);
2262 	return true;
2263 }
2264 
2265 /**
2266  * rcvbuf_limit - get proper overload limit of socket receive queue
2267  * @sk: socket
2268  * @skb: message
2269  *
2270  * For connection oriented messages, irrespective of importance,
2271  * default queue limit is 2 MB.
2272  *
2273  * For connectionless messages, queue limits are based on message
2274  * importance as follows:
2275  *
2276  * TIPC_LOW_IMPORTANCE       (2 MB)
2277  * TIPC_MEDIUM_IMPORTANCE    (4 MB)
2278  * TIPC_HIGH_IMPORTANCE      (8 MB)
2279  * TIPC_CRITICAL_IMPORTANCE  (16 MB)
2280  *
2281  * Return: overload limit according to corresponding message importance
2282  */
2283 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb)
2284 {
2285 	struct tipc_sock *tsk = tipc_sk(sk);
2286 	struct tipc_msg *hdr = buf_msg(skb);
2287 
2288 	if (unlikely(msg_in_group(hdr)))
2289 		return READ_ONCE(sk->sk_rcvbuf);
2290 
2291 	if (unlikely(!msg_connected(hdr)))
2292 		return READ_ONCE(sk->sk_rcvbuf) << msg_importance(hdr);
2293 
2294 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
2295 		return READ_ONCE(sk->sk_rcvbuf);
2296 
2297 	return FLOWCTL_MSG_LIM;
2298 }
2299 
2300 /**
2301  * tipc_sk_filter_rcv - validate incoming message
2302  * @sk: socket
2303  * @skb: pointer to message.
2304  * @xmitq: output message area (FIXME)
2305  *
2306  * Enqueues message on receive queue if acceptable; optionally handles
2307  * disconnect indication for a connected socket.
2308  *
2309  * Called with socket lock already taken
2310  */
2311 static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb,
2312 			       struct sk_buff_head *xmitq)
2313 {
2314 	bool sk_conn = !tipc_sk_type_connectionless(sk);
2315 	struct tipc_sock *tsk = tipc_sk(sk);
2316 	struct tipc_group *grp = tsk->group;
2317 	struct tipc_msg *hdr = buf_msg(skb);
2318 	struct net *net = sock_net(sk);
2319 	struct sk_buff_head inputq;
2320 	int mtyp = msg_type(hdr);
2321 	int limit, err = TIPC_OK;
2322 
2323 	trace_tipc_sk_filter_rcv(sk, skb, TIPC_DUMP_ALL, " ");
2324 	TIPC_SKB_CB(skb)->bytes_read = 0;
2325 	__skb_queue_head_init(&inputq);
2326 	__skb_queue_tail(&inputq, skb);
2327 
2328 	if (unlikely(!msg_isdata(hdr)))
2329 		tipc_sk_proto_rcv(sk, &inputq, xmitq);
2330 
2331 	if (unlikely(grp))
2332 		tipc_group_filter_msg(grp, &inputq, xmitq);
2333 
2334 	if (unlikely(!grp) && mtyp == TIPC_MCAST_MSG)
2335 		tipc_mcast_filter_msg(net, &tsk->mc_method.deferredq, &inputq);
2336 
2337 	/* Validate and add to receive buffer if there is space */
2338 	while ((skb = __skb_dequeue(&inputq))) {
2339 		hdr = buf_msg(skb);
2340 		limit = rcvbuf_limit(sk, skb);
2341 		if ((sk_conn && !tipc_sk_filter_connect(tsk, skb, xmitq)) ||
2342 		    (!sk_conn && msg_connected(hdr)) ||
2343 		    (!grp && msg_in_group(hdr)))
2344 			err = TIPC_ERR_NO_PORT;
2345 		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit) {
2346 			trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL,
2347 					   "err_overload2!");
2348 			atomic_inc(&sk->sk_drops);
2349 			err = TIPC_ERR_OVERLOAD;
2350 		}
2351 
2352 		if (unlikely(err)) {
2353 			if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) {
2354 				trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE,
2355 						      "@filter_rcv!");
2356 				__skb_queue_tail(xmitq, skb);
2357 			}
2358 			err = TIPC_OK;
2359 			continue;
2360 		}
2361 		__skb_queue_tail(&sk->sk_receive_queue, skb);
2362 		skb_set_owner_r(skb, sk);
2363 		trace_tipc_sk_overlimit2(sk, skb, TIPC_DUMP_ALL,
2364 					 "rcvq >90% allocated!");
2365 		sk->sk_data_ready(sk);
2366 	}
2367 }
2368 
2369 /**
2370  * tipc_sk_backlog_rcv - handle incoming message from backlog queue
2371  * @sk: socket
2372  * @skb: message
2373  *
2374  * Caller must hold socket lock
2375  */
2376 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
2377 {
2378 	unsigned int before = sk_rmem_alloc_get(sk);
2379 	struct sk_buff_head xmitq;
2380 	unsigned int added;
2381 
2382 	__skb_queue_head_init(&xmitq);
2383 
2384 	tipc_sk_filter_rcv(sk, skb, &xmitq);
2385 	added = sk_rmem_alloc_get(sk) - before;
2386 	atomic_add(added, &tipc_sk(sk)->dupl_rcvcnt);
2387 
2388 	/* Send pending response/rejected messages, if any */
2389 	tipc_node_distr_xmit(sock_net(sk), &xmitq);
2390 	return 0;
2391 }
2392 
2393 /**
2394  * tipc_sk_enqueue - extract all buffers with destination 'dport' from
2395  *                   inputq and try adding them to socket or backlog queue
2396  * @inputq: list of incoming buffers with potentially different destinations
2397  * @sk: socket where the buffers should be enqueued
2398  * @dport: port number for the socket
2399  * @xmitq: output queue
2400  *
2401  * Caller must hold socket lock
2402  */
2403 static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
2404 			    u32 dport, struct sk_buff_head *xmitq)
2405 {
2406 	unsigned long time_limit = jiffies + 2;
2407 	struct sk_buff *skb;
2408 	unsigned int lim;
2409 	atomic_t *dcnt;
2410 	u32 onode;
2411 
2412 	while (skb_queue_len(inputq)) {
2413 		if (unlikely(time_after_eq(jiffies, time_limit)))
2414 			return;
2415 
2416 		skb = tipc_skb_dequeue(inputq, dport);
2417 		if (unlikely(!skb))
2418 			return;
2419 
2420 		/* Add message directly to receive queue if possible */
2421 		if (!sock_owned_by_user(sk)) {
2422 			tipc_sk_filter_rcv(sk, skb, xmitq);
2423 			continue;
2424 		}
2425 
2426 		/* Try backlog, compensating for double-counted bytes */
2427 		dcnt = &tipc_sk(sk)->dupl_rcvcnt;
2428 		if (!sk->sk_backlog.len)
2429 			atomic_set(dcnt, 0);
2430 		lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
2431 		if (likely(!sk_add_backlog(sk, skb, lim))) {
2432 			trace_tipc_sk_overlimit1(sk, skb, TIPC_DUMP_ALL,
2433 						 "bklg & rcvq >90% allocated!");
2434 			continue;
2435 		}
2436 
2437 		trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL, "err_overload!");
2438 		/* Overload => reject message back to sender */
2439 		onode = tipc_own_addr(sock_net(sk));
2440 		atomic_inc(&sk->sk_drops);
2441 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD)) {
2442 			trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_ALL,
2443 					      "@sk_enqueue!");
2444 			__skb_queue_tail(xmitq, skb);
2445 		}
2446 		break;
2447 	}
2448 }
2449 
2450 /**
2451  * tipc_sk_rcv - handle a chain of incoming buffers
2452  * @net: the associated network namespace
2453  * @inputq: buffer list containing the buffers
2454  * Consumes all buffers in list until inputq is empty
2455  * Note: may be called in multiple threads referring to the same queue
2456  */
2457 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq)
2458 {
2459 	struct sk_buff_head xmitq;
2460 	u32 dnode, dport = 0;
2461 	int err;
2462 	struct tipc_sock *tsk;
2463 	struct sock *sk;
2464 	struct sk_buff *skb;
2465 
2466 	__skb_queue_head_init(&xmitq);
2467 	while (skb_queue_len(inputq)) {
2468 		dport = tipc_skb_peek_port(inputq, dport);
2469 		tsk = tipc_sk_lookup(net, dport);
2470 
2471 		if (likely(tsk)) {
2472 			sk = &tsk->sk;
2473 			if (likely(spin_trylock_bh(&sk->sk_lock.slock))) {
2474 				tipc_sk_enqueue(inputq, sk, dport, &xmitq);
2475 				spin_unlock_bh(&sk->sk_lock.slock);
2476 			}
2477 			/* Send pending response/rejected messages, if any */
2478 			tipc_node_distr_xmit(sock_net(sk), &xmitq);
2479 			sock_put(sk);
2480 			continue;
2481 		}
2482 		/* No destination socket => dequeue skb if still there */
2483 		skb = tipc_skb_dequeue(inputq, dport);
2484 		if (!skb)
2485 			return;
2486 
2487 		/* Try secondary lookup if unresolved named message */
2488 		err = TIPC_ERR_NO_PORT;
2489 		if (tipc_msg_lookup_dest(net, skb, &err))
2490 			goto xmit;
2491 
2492 		/* Prepare for message rejection */
2493 		if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err))
2494 			continue;
2495 
2496 		trace_tipc_sk_rej_msg(NULL, skb, TIPC_DUMP_NONE, "@sk_rcv!");
2497 xmit:
2498 		dnode = msg_destnode(buf_msg(skb));
2499 		tipc_node_xmit_skb(net, skb, dnode, dport);
2500 	}
2501 }
2502 
2503 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
2504 {
2505 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2506 	struct sock *sk = sock->sk;
2507 	int done;
2508 
2509 	do {
2510 		int err = sock_error(sk);
2511 		if (err)
2512 			return err;
2513 		if (!*timeo_p)
2514 			return -ETIMEDOUT;
2515 		if (signal_pending(current))
2516 			return sock_intr_errno(*timeo_p);
2517 		if (sk->sk_state == TIPC_DISCONNECTING)
2518 			break;
2519 
2520 		add_wait_queue(sk_sleep(sk), &wait);
2521 		done = sk_wait_event(sk, timeo_p, tipc_sk_connected(sk),
2522 				     &wait);
2523 		remove_wait_queue(sk_sleep(sk), &wait);
2524 	} while (!done);
2525 	return 0;
2526 }
2527 
2528 static bool tipc_sockaddr_is_sane(struct sockaddr_tipc *addr)
2529 {
2530 	if (addr->family != AF_TIPC)
2531 		return false;
2532 	if (addr->addrtype == TIPC_SERVICE_RANGE)
2533 		return (addr->addr.nameseq.lower <= addr->addr.nameseq.upper);
2534 	return (addr->addrtype == TIPC_SERVICE_ADDR ||
2535 		addr->addrtype == TIPC_SOCKET_ADDR);
2536 }
2537 
2538 /**
2539  * tipc_connect - establish a connection to another TIPC port
2540  * @sock: socket structure
2541  * @dest: socket address for destination port
2542  * @destlen: size of socket address data structure
2543  * @flags: file-related flags associated with socket
2544  *
2545  * Return: 0 on success, errno otherwise
2546  */
2547 static int tipc_connect(struct socket *sock, struct sockaddr *dest,
2548 			int destlen, int flags)
2549 {
2550 	struct sock *sk = sock->sk;
2551 	struct tipc_sock *tsk = tipc_sk(sk);
2552 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
2553 	struct msghdr m = {NULL,};
2554 	long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout;
2555 	int previous;
2556 	int res = 0;
2557 
2558 	if (destlen != sizeof(struct sockaddr_tipc))
2559 		return -EINVAL;
2560 
2561 	lock_sock(sk);
2562 
2563 	if (tsk->group) {
2564 		res = -EINVAL;
2565 		goto exit;
2566 	}
2567 
2568 	if (dst->family == AF_UNSPEC) {
2569 		memset(&tsk->peer, 0, sizeof(struct sockaddr_tipc));
2570 		if (!tipc_sk_type_connectionless(sk))
2571 			res = -EINVAL;
2572 		goto exit;
2573 	}
2574 	if (!tipc_sockaddr_is_sane(dst)) {
2575 		res = -EINVAL;
2576 		goto exit;
2577 	}
2578 	/* DGRAM/RDM connect(), just save the destaddr */
2579 	if (tipc_sk_type_connectionless(sk)) {
2580 		memcpy(&tsk->peer, dest, destlen);
2581 		goto exit;
2582 	} else if (dst->addrtype == TIPC_SERVICE_RANGE) {
2583 		res = -EINVAL;
2584 		goto exit;
2585 	}
2586 
2587 	previous = sk->sk_state;
2588 
2589 	switch (sk->sk_state) {
2590 	case TIPC_OPEN:
2591 		/* Send a 'SYN-' to destination */
2592 		m.msg_name = dest;
2593 		m.msg_namelen = destlen;
2594 
2595 		/* If connect is in non-blocking case, set MSG_DONTWAIT to
2596 		 * indicate send_msg() is never blocked.
2597 		 */
2598 		if (!timeout)
2599 			m.msg_flags = MSG_DONTWAIT;
2600 
2601 		res = __tipc_sendmsg(sock, &m, 0);
2602 		if ((res < 0) && (res != -EWOULDBLOCK))
2603 			goto exit;
2604 
2605 		/* Just entered TIPC_CONNECTING state; the only
2606 		 * difference is that return value in non-blocking
2607 		 * case is EINPROGRESS, rather than EALREADY.
2608 		 */
2609 		res = -EINPROGRESS;
2610 		fallthrough;
2611 	case TIPC_CONNECTING:
2612 		if (!timeout) {
2613 			if (previous == TIPC_CONNECTING)
2614 				res = -EALREADY;
2615 			goto exit;
2616 		}
2617 		timeout = msecs_to_jiffies(timeout);
2618 		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
2619 		res = tipc_wait_for_connect(sock, &timeout);
2620 		break;
2621 	case TIPC_ESTABLISHED:
2622 		res = -EISCONN;
2623 		break;
2624 	default:
2625 		res = -EINVAL;
2626 	}
2627 
2628 exit:
2629 	release_sock(sk);
2630 	return res;
2631 }
2632 
2633 /**
2634  * tipc_listen - allow socket to listen for incoming connections
2635  * @sock: socket structure
2636  * @len: (unused)
2637  *
2638  * Return: 0 on success, errno otherwise
2639  */
2640 static int tipc_listen(struct socket *sock, int len)
2641 {
2642 	struct sock *sk = sock->sk;
2643 	int res;
2644 
2645 	lock_sock(sk);
2646 	res = tipc_set_sk_state(sk, TIPC_LISTEN);
2647 	release_sock(sk);
2648 
2649 	return res;
2650 }
2651 
2652 static int tipc_wait_for_accept(struct socket *sock, long timeo)
2653 {
2654 	struct sock *sk = sock->sk;
2655 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2656 	int err;
2657 
2658 	/* True wake-one mechanism for incoming connections: only
2659 	 * one process gets woken up, not the 'whole herd'.
2660 	 * Since we do not 'race & poll' for established sockets
2661 	 * anymore, the common case will execute the loop only once.
2662 	*/
2663 	for (;;) {
2664 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
2665 			add_wait_queue(sk_sleep(sk), &wait);
2666 			release_sock(sk);
2667 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
2668 			lock_sock(sk);
2669 			remove_wait_queue(sk_sleep(sk), &wait);
2670 		}
2671 		err = 0;
2672 		if (!skb_queue_empty(&sk->sk_receive_queue))
2673 			break;
2674 		err = -EAGAIN;
2675 		if (!timeo)
2676 			break;
2677 		err = sock_intr_errno(timeo);
2678 		if (signal_pending(current))
2679 			break;
2680 	}
2681 	return err;
2682 }
2683 
2684 /**
2685  * tipc_accept - wait for connection request
2686  * @sock: listening socket
2687  * @new_sock: new socket that is to be connected
2688  * @flags: file-related flags associated with socket
2689  * @kern: caused by kernel or by userspace?
2690  *
2691  * Return: 0 on success, errno otherwise
2692  */
2693 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
2694 		       bool kern)
2695 {
2696 	struct sock *new_sk, *sk = sock->sk;
2697 	struct tipc_sock *new_tsock;
2698 	struct msghdr m = {NULL,};
2699 	struct tipc_msg *msg;
2700 	struct sk_buff *buf;
2701 	long timeo;
2702 	int res;
2703 
2704 	lock_sock(sk);
2705 
2706 	if (sk->sk_state != TIPC_LISTEN) {
2707 		res = -EINVAL;
2708 		goto exit;
2709 	}
2710 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2711 	res = tipc_wait_for_accept(sock, timeo);
2712 	if (res)
2713 		goto exit;
2714 
2715 	buf = skb_peek(&sk->sk_receive_queue);
2716 
2717 	res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, kern);
2718 	if (res)
2719 		goto exit;
2720 	security_sk_clone(sock->sk, new_sock->sk);
2721 
2722 	new_sk = new_sock->sk;
2723 	new_tsock = tipc_sk(new_sk);
2724 	msg = buf_msg(buf);
2725 
2726 	/* we lock on new_sk; but lockdep sees the lock on sk */
2727 	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
2728 
2729 	/*
2730 	 * Reject any stray messages received by new socket
2731 	 * before the socket lock was taken (very, very unlikely)
2732 	 */
2733 	tsk_rej_rx_queue(new_sk, TIPC_ERR_NO_PORT);
2734 
2735 	/* Connect new socket to it's peer */
2736 	tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg));
2737 
2738 	tsk_set_importance(new_sk, msg_importance(msg));
2739 	if (msg_named(msg)) {
2740 		new_tsock->conn_addrtype = TIPC_SERVICE_ADDR;
2741 		msg_set_nametype(&new_tsock->phdr, msg_nametype(msg));
2742 		msg_set_nameinst(&new_tsock->phdr, msg_nameinst(msg));
2743 	}
2744 
2745 	/*
2746 	 * Respond to 'SYN-' by discarding it & returning 'ACK'.
2747 	 * Respond to 'SYN+' by queuing it on new socket & returning 'ACK'.
2748 	 */
2749 	if (!msg_data_sz(msg)) {
2750 		tsk_advance_rx_queue(sk);
2751 	} else {
2752 		__skb_dequeue(&sk->sk_receive_queue);
2753 		__skb_queue_head(&new_sk->sk_receive_queue, buf);
2754 		skb_set_owner_r(buf, new_sk);
2755 	}
2756 	__tipc_sendstream(new_sock, &m, 0);
2757 	release_sock(new_sk);
2758 exit:
2759 	release_sock(sk);
2760 	return res;
2761 }
2762 
2763 /**
2764  * tipc_shutdown - shutdown socket connection
2765  * @sock: socket structure
2766  * @how: direction to close (must be SHUT_RDWR)
2767  *
2768  * Terminates connection (if necessary), then purges socket's receive queue.
2769  *
2770  * Return: 0 on success, errno otherwise
2771  */
2772 static int tipc_shutdown(struct socket *sock, int how)
2773 {
2774 	struct sock *sk = sock->sk;
2775 	int res;
2776 
2777 	if (how != SHUT_RDWR)
2778 		return -EINVAL;
2779 
2780 	lock_sock(sk);
2781 
2782 	trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " ");
2783 	__tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
2784 	sk->sk_shutdown = SHUTDOWN_MASK;
2785 
2786 	if (sk->sk_state == TIPC_DISCONNECTING) {
2787 		/* Discard any unreceived messages */
2788 		__skb_queue_purge(&sk->sk_receive_queue);
2789 
2790 		res = 0;
2791 	} else {
2792 		res = -ENOTCONN;
2793 	}
2794 	/* Wake up anyone sleeping in poll. */
2795 	sk->sk_state_change(sk);
2796 
2797 	release_sock(sk);
2798 	return res;
2799 }
2800 
2801 static void tipc_sk_check_probing_state(struct sock *sk,
2802 					struct sk_buff_head *list)
2803 {
2804 	struct tipc_sock *tsk = tipc_sk(sk);
2805 	u32 pnode = tsk_peer_node(tsk);
2806 	u32 pport = tsk_peer_port(tsk);
2807 	u32 self = tsk_own_node(tsk);
2808 	u32 oport = tsk->portid;
2809 	struct sk_buff *skb;
2810 
2811 	if (tsk->probe_unacked) {
2812 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2813 		sk->sk_err = ECONNABORTED;
2814 		tipc_node_remove_conn(sock_net(sk), pnode, pport);
2815 		sk->sk_state_change(sk);
2816 		return;
2817 	}
2818 	/* Prepare new probe */
2819 	skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE, INT_H_SIZE, 0,
2820 			      pnode, self, pport, oport, TIPC_OK);
2821 	if (skb)
2822 		__skb_queue_tail(list, skb);
2823 	tsk->probe_unacked = true;
2824 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
2825 }
2826 
2827 static void tipc_sk_retry_connect(struct sock *sk, struct sk_buff_head *list)
2828 {
2829 	struct tipc_sock *tsk = tipc_sk(sk);
2830 
2831 	/* Try again later if dest link is congested */
2832 	if (tsk->cong_link_cnt) {
2833 		sk_reset_timer(sk, &sk->sk_timer, msecs_to_jiffies(100));
2834 		return;
2835 	}
2836 	/* Prepare SYN for retransmit */
2837 	tipc_msg_skb_clone(&sk->sk_write_queue, list);
2838 }
2839 
2840 static void tipc_sk_timeout(struct timer_list *t)
2841 {
2842 	struct sock *sk = from_timer(sk, t, sk_timer);
2843 	struct tipc_sock *tsk = tipc_sk(sk);
2844 	u32 pnode = tsk_peer_node(tsk);
2845 	struct sk_buff_head list;
2846 	int rc = 0;
2847 
2848 	__skb_queue_head_init(&list);
2849 	bh_lock_sock(sk);
2850 
2851 	/* Try again later if socket is busy */
2852 	if (sock_owned_by_user(sk)) {
2853 		sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 20);
2854 		bh_unlock_sock(sk);
2855 		sock_put(sk);
2856 		return;
2857 	}
2858 
2859 	if (sk->sk_state == TIPC_ESTABLISHED)
2860 		tipc_sk_check_probing_state(sk, &list);
2861 	else if (sk->sk_state == TIPC_CONNECTING)
2862 		tipc_sk_retry_connect(sk, &list);
2863 
2864 	bh_unlock_sock(sk);
2865 
2866 	if (!skb_queue_empty(&list))
2867 		rc = tipc_node_xmit(sock_net(sk), &list, pnode, tsk->portid);
2868 
2869 	/* SYN messages may cause link congestion */
2870 	if (rc == -ELINKCONG) {
2871 		tipc_dest_push(&tsk->cong_links, pnode, 0);
2872 		tsk->cong_link_cnt = 1;
2873 	}
2874 	sock_put(sk);
2875 }
2876 
2877 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2878 {
2879 	struct sock *sk = &tsk->sk;
2880 	struct net *net = sock_net(sk);
2881 	struct tipc_socket_addr skaddr;
2882 	struct publication *p;
2883 	u32 key;
2884 
2885 	if (tipc_sk_connected(sk))
2886 		return -EINVAL;
2887 	key = tsk->portid + tsk->pub_count + 1;
2888 	if (key == tsk->portid)
2889 		return -EADDRINUSE;
2890 	skaddr.ref = tsk->portid;
2891 	skaddr.node = tipc_own_addr(net);
2892 	p = tipc_nametbl_publish(net, ua, &skaddr, key);
2893 	if (unlikely(!p))
2894 		return -EINVAL;
2895 
2896 	list_add(&p->binding_sock, &tsk->publications);
2897 	tsk->pub_count++;
2898 	tsk->published = true;
2899 	return 0;
2900 }
2901 
2902 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2903 {
2904 	struct net *net = sock_net(&tsk->sk);
2905 	struct publication *safe, *p;
2906 	struct tipc_uaddr _ua;
2907 	int rc = -EINVAL;
2908 
2909 	list_for_each_entry_safe(p, safe, &tsk->publications, binding_sock) {
2910 		if (!ua) {
2911 			tipc_uaddr(&_ua, TIPC_SERVICE_RANGE, p->scope,
2912 				   p->sr.type, p->sr.lower, p->sr.upper);
2913 			tipc_nametbl_withdraw(net, &_ua, &p->sk, p->key);
2914 			continue;
2915 		}
2916 		/* Unbind specific publication */
2917 		if (p->scope != ua->scope)
2918 			continue;
2919 		if (p->sr.type != ua->sr.type)
2920 			continue;
2921 		if (p->sr.lower != ua->sr.lower)
2922 			continue;
2923 		if (p->sr.upper != ua->sr.upper)
2924 			break;
2925 		tipc_nametbl_withdraw(net, ua, &p->sk, p->key);
2926 		rc = 0;
2927 		break;
2928 	}
2929 	if (list_empty(&tsk->publications)) {
2930 		tsk->published = 0;
2931 		rc = 0;
2932 	}
2933 	return rc;
2934 }
2935 
2936 /* tipc_sk_reinit: set non-zero address in all existing sockets
2937  *                 when we go from standalone to network mode.
2938  */
2939 void tipc_sk_reinit(struct net *net)
2940 {
2941 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2942 	struct rhashtable_iter iter;
2943 	struct tipc_sock *tsk;
2944 	struct tipc_msg *msg;
2945 
2946 	rhashtable_walk_enter(&tn->sk_rht, &iter);
2947 
2948 	do {
2949 		rhashtable_walk_start(&iter);
2950 
2951 		while ((tsk = rhashtable_walk_next(&iter)) && !IS_ERR(tsk)) {
2952 			sock_hold(&tsk->sk);
2953 			rhashtable_walk_stop(&iter);
2954 			lock_sock(&tsk->sk);
2955 			msg = &tsk->phdr;
2956 			msg_set_prevnode(msg, tipc_own_addr(net));
2957 			msg_set_orignode(msg, tipc_own_addr(net));
2958 			release_sock(&tsk->sk);
2959 			rhashtable_walk_start(&iter);
2960 			sock_put(&tsk->sk);
2961 		}
2962 
2963 		rhashtable_walk_stop(&iter);
2964 	} while (tsk == ERR_PTR(-EAGAIN));
2965 
2966 	rhashtable_walk_exit(&iter);
2967 }
2968 
2969 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)
2970 {
2971 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2972 	struct tipc_sock *tsk;
2973 
2974 	rcu_read_lock();
2975 	tsk = rhashtable_lookup(&tn->sk_rht, &portid, tsk_rht_params);
2976 	if (tsk)
2977 		sock_hold(&tsk->sk);
2978 	rcu_read_unlock();
2979 
2980 	return tsk;
2981 }
2982 
2983 static int tipc_sk_insert(struct tipc_sock *tsk)
2984 {
2985 	struct sock *sk = &tsk->sk;
2986 	struct net *net = sock_net(sk);
2987 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2988 	u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1;
2989 	u32 portid = prandom_u32() % remaining + TIPC_MIN_PORT;
2990 
2991 	while (remaining--) {
2992 		portid++;
2993 		if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT))
2994 			portid = TIPC_MIN_PORT;
2995 		tsk->portid = portid;
2996 		sock_hold(&tsk->sk);
2997 		if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node,
2998 						   tsk_rht_params))
2999 			return 0;
3000 		sock_put(&tsk->sk);
3001 	}
3002 
3003 	return -1;
3004 }
3005 
3006 static void tipc_sk_remove(struct tipc_sock *tsk)
3007 {
3008 	struct sock *sk = &tsk->sk;
3009 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
3010 
3011 	if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) {
3012 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
3013 		__sock_put(sk);
3014 	}
3015 }
3016 
3017 static const struct rhashtable_params tsk_rht_params = {
3018 	.nelem_hint = 192,
3019 	.head_offset = offsetof(struct tipc_sock, node),
3020 	.key_offset = offsetof(struct tipc_sock, portid),
3021 	.key_len = sizeof(u32), /* portid */
3022 	.max_size = 1048576,
3023 	.min_size = 256,
3024 	.automatic_shrinking = true,
3025 };
3026 
3027 int tipc_sk_rht_init(struct net *net)
3028 {
3029 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3030 
3031 	return rhashtable_init(&tn->sk_rht, &tsk_rht_params);
3032 }
3033 
3034 void tipc_sk_rht_destroy(struct net *net)
3035 {
3036 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3037 
3038 	/* Wait for socket readers to complete */
3039 	synchronize_net();
3040 
3041 	rhashtable_destroy(&tn->sk_rht);
3042 }
3043 
3044 static int tipc_sk_join(struct tipc_sock *tsk, struct tipc_group_req *mreq)
3045 {
3046 	struct net *net = sock_net(&tsk->sk);
3047 	struct tipc_group *grp = tsk->group;
3048 	struct tipc_msg *hdr = &tsk->phdr;
3049 	struct tipc_uaddr ua;
3050 	int rc;
3051 
3052 	if (mreq->type < TIPC_RESERVED_TYPES)
3053 		return -EACCES;
3054 	if (mreq->scope > TIPC_NODE_SCOPE)
3055 		return -EINVAL;
3056 	if (mreq->scope != TIPC_NODE_SCOPE)
3057 		mreq->scope = TIPC_CLUSTER_SCOPE;
3058 	if (grp)
3059 		return -EACCES;
3060 	grp = tipc_group_create(net, tsk->portid, mreq, &tsk->group_is_open);
3061 	if (!grp)
3062 		return -ENOMEM;
3063 	tsk->group = grp;
3064 	msg_set_lookup_scope(hdr, mreq->scope);
3065 	msg_set_nametype(hdr, mreq->type);
3066 	msg_set_dest_droppable(hdr, true);
3067 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, mreq->scope,
3068 		   mreq->type, mreq->instance, mreq->instance);
3069 	tipc_nametbl_build_group(net, grp, &ua);
3070 	rc = tipc_sk_publish(tsk, &ua);
3071 	if (rc) {
3072 		tipc_group_delete(net, grp);
3073 		tsk->group = NULL;
3074 		return rc;
3075 	}
3076 	/* Eliminate any risk that a broadcast overtakes sent JOINs */
3077 	tsk->mc_method.rcast = true;
3078 	tsk->mc_method.mandatory = true;
3079 	tipc_group_join(net, grp, &tsk->sk.sk_rcvbuf);
3080 	return rc;
3081 }
3082 
3083 static int tipc_sk_leave(struct tipc_sock *tsk)
3084 {
3085 	struct net *net = sock_net(&tsk->sk);
3086 	struct tipc_group *grp = tsk->group;
3087 	struct tipc_uaddr ua;
3088 	int scope;
3089 
3090 	if (!grp)
3091 		return -EINVAL;
3092 	ua.addrtype = TIPC_SERVICE_RANGE;
3093 	tipc_group_self(grp, &ua.sr, &scope);
3094 	ua.scope = scope;
3095 	tipc_group_delete(net, grp);
3096 	tsk->group = NULL;
3097 	tipc_sk_withdraw(tsk, &ua);
3098 	return 0;
3099 }
3100 
3101 /**
3102  * tipc_setsockopt - set socket option
3103  * @sock: socket structure
3104  * @lvl: option level
3105  * @opt: option identifier
3106  * @ov: pointer to new option value
3107  * @ol: length of option value
3108  *
3109  * For stream sockets only, accepts and ignores all IPPROTO_TCP options
3110  * (to ease compatibility).
3111  *
3112  * Return: 0 on success, errno otherwise
3113  */
3114 static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
3115 			   sockptr_t ov, unsigned int ol)
3116 {
3117 	struct sock *sk = sock->sk;
3118 	struct tipc_sock *tsk = tipc_sk(sk);
3119 	struct tipc_group_req mreq;
3120 	u32 value = 0;
3121 	int res = 0;
3122 
3123 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
3124 		return 0;
3125 	if (lvl != SOL_TIPC)
3126 		return -ENOPROTOOPT;
3127 
3128 	switch (opt) {
3129 	case TIPC_IMPORTANCE:
3130 	case TIPC_SRC_DROPPABLE:
3131 	case TIPC_DEST_DROPPABLE:
3132 	case TIPC_CONN_TIMEOUT:
3133 	case TIPC_NODELAY:
3134 		if (ol < sizeof(value))
3135 			return -EINVAL;
3136 		if (copy_from_sockptr(&value, ov, sizeof(u32)))
3137 			return -EFAULT;
3138 		break;
3139 	case TIPC_GROUP_JOIN:
3140 		if (ol < sizeof(mreq))
3141 			return -EINVAL;
3142 		if (copy_from_sockptr(&mreq, ov, sizeof(mreq)))
3143 			return -EFAULT;
3144 		break;
3145 	default:
3146 		if (!sockptr_is_null(ov) || ol)
3147 			return -EINVAL;
3148 	}
3149 
3150 	lock_sock(sk);
3151 
3152 	switch (opt) {
3153 	case TIPC_IMPORTANCE:
3154 		res = tsk_set_importance(sk, value);
3155 		break;
3156 	case TIPC_SRC_DROPPABLE:
3157 		if (sock->type != SOCK_STREAM)
3158 			tsk_set_unreliable(tsk, value);
3159 		else
3160 			res = -ENOPROTOOPT;
3161 		break;
3162 	case TIPC_DEST_DROPPABLE:
3163 		tsk_set_unreturnable(tsk, value);
3164 		break;
3165 	case TIPC_CONN_TIMEOUT:
3166 		tipc_sk(sk)->conn_timeout = value;
3167 		break;
3168 	case TIPC_MCAST_BROADCAST:
3169 		tsk->mc_method.rcast = false;
3170 		tsk->mc_method.mandatory = true;
3171 		break;
3172 	case TIPC_MCAST_REPLICAST:
3173 		tsk->mc_method.rcast = true;
3174 		tsk->mc_method.mandatory = true;
3175 		break;
3176 	case TIPC_GROUP_JOIN:
3177 		res = tipc_sk_join(tsk, &mreq);
3178 		break;
3179 	case TIPC_GROUP_LEAVE:
3180 		res = tipc_sk_leave(tsk);
3181 		break;
3182 	case TIPC_NODELAY:
3183 		tsk->nodelay = !!value;
3184 		tsk_set_nagle(tsk);
3185 		break;
3186 	default:
3187 		res = -EINVAL;
3188 	}
3189 
3190 	release_sock(sk);
3191 
3192 	return res;
3193 }
3194 
3195 /**
3196  * tipc_getsockopt - get socket option
3197  * @sock: socket structure
3198  * @lvl: option level
3199  * @opt: option identifier
3200  * @ov: receptacle for option value
3201  * @ol: receptacle for length of option value
3202  *
3203  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
3204  * (to ease compatibility).
3205  *
3206  * Return: 0 on success, errno otherwise
3207  */
3208 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
3209 			   char __user *ov, int __user *ol)
3210 {
3211 	struct sock *sk = sock->sk;
3212 	struct tipc_sock *tsk = tipc_sk(sk);
3213 	struct tipc_service_range seq;
3214 	int len, scope;
3215 	u32 value;
3216 	int res;
3217 
3218 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
3219 		return put_user(0, ol);
3220 	if (lvl != SOL_TIPC)
3221 		return -ENOPROTOOPT;
3222 	res = get_user(len, ol);
3223 	if (res)
3224 		return res;
3225 
3226 	lock_sock(sk);
3227 
3228 	switch (opt) {
3229 	case TIPC_IMPORTANCE:
3230 		value = tsk_importance(tsk);
3231 		break;
3232 	case TIPC_SRC_DROPPABLE:
3233 		value = tsk_unreliable(tsk);
3234 		break;
3235 	case TIPC_DEST_DROPPABLE:
3236 		value = tsk_unreturnable(tsk);
3237 		break;
3238 	case TIPC_CONN_TIMEOUT:
3239 		value = tsk->conn_timeout;
3240 		/* no need to set "res", since already 0 at this point */
3241 		break;
3242 	case TIPC_NODE_RECVQ_DEPTH:
3243 		value = 0; /* was tipc_queue_size, now obsolete */
3244 		break;
3245 	case TIPC_SOCK_RECVQ_DEPTH:
3246 		value = skb_queue_len(&sk->sk_receive_queue);
3247 		break;
3248 	case TIPC_SOCK_RECVQ_USED:
3249 		value = sk_rmem_alloc_get(sk);
3250 		break;
3251 	case TIPC_GROUP_JOIN:
3252 		seq.type = 0;
3253 		if (tsk->group)
3254 			tipc_group_self(tsk->group, &seq, &scope);
3255 		value = seq.type;
3256 		break;
3257 	default:
3258 		res = -EINVAL;
3259 	}
3260 
3261 	release_sock(sk);
3262 
3263 	if (res)
3264 		return res;	/* "get" failed */
3265 
3266 	if (len < sizeof(value))
3267 		return -EINVAL;
3268 
3269 	if (copy_to_user(ov, &value, sizeof(value)))
3270 		return -EFAULT;
3271 
3272 	return put_user(sizeof(value), ol);
3273 }
3274 
3275 static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3276 {
3277 	struct net *net = sock_net(sock->sk);
3278 	struct tipc_sioc_nodeid_req nr = {0};
3279 	struct tipc_sioc_ln_req lnr;
3280 	void __user *argp = (void __user *)arg;
3281 
3282 	switch (cmd) {
3283 	case SIOCGETLINKNAME:
3284 		if (copy_from_user(&lnr, argp, sizeof(lnr)))
3285 			return -EFAULT;
3286 		if (!tipc_node_get_linkname(net,
3287 					    lnr.bearer_id & 0xffff, lnr.peer,
3288 					    lnr.linkname, TIPC_MAX_LINK_NAME)) {
3289 			if (copy_to_user(argp, &lnr, sizeof(lnr)))
3290 				return -EFAULT;
3291 			return 0;
3292 		}
3293 		return -EADDRNOTAVAIL;
3294 	case SIOCGETNODEID:
3295 		if (copy_from_user(&nr, argp, sizeof(nr)))
3296 			return -EFAULT;
3297 		if (!tipc_node_get_id(net, nr.peer, nr.node_id))
3298 			return -EADDRNOTAVAIL;
3299 		if (copy_to_user(argp, &nr, sizeof(nr)))
3300 			return -EFAULT;
3301 		return 0;
3302 	default:
3303 		return -ENOIOCTLCMD;
3304 	}
3305 }
3306 
3307 static int tipc_socketpair(struct socket *sock1, struct socket *sock2)
3308 {
3309 	struct tipc_sock *tsk2 = tipc_sk(sock2->sk);
3310 	struct tipc_sock *tsk1 = tipc_sk(sock1->sk);
3311 	u32 onode = tipc_own_addr(sock_net(sock1->sk));
3312 
3313 	tsk1->peer.family = AF_TIPC;
3314 	tsk1->peer.addrtype = TIPC_SOCKET_ADDR;
3315 	tsk1->peer.scope = TIPC_NODE_SCOPE;
3316 	tsk1->peer.addr.id.ref = tsk2->portid;
3317 	tsk1->peer.addr.id.node = onode;
3318 	tsk2->peer.family = AF_TIPC;
3319 	tsk2->peer.addrtype = TIPC_SOCKET_ADDR;
3320 	tsk2->peer.scope = TIPC_NODE_SCOPE;
3321 	tsk2->peer.addr.id.ref = tsk1->portid;
3322 	tsk2->peer.addr.id.node = onode;
3323 
3324 	tipc_sk_finish_conn(tsk1, tsk2->portid, onode);
3325 	tipc_sk_finish_conn(tsk2, tsk1->portid, onode);
3326 	return 0;
3327 }
3328 
3329 /* Protocol switches for the various types of TIPC sockets */
3330 
3331 static const struct proto_ops msg_ops = {
3332 	.owner		= THIS_MODULE,
3333 	.family		= AF_TIPC,
3334 	.release	= tipc_release,
3335 	.bind		= tipc_bind,
3336 	.connect	= tipc_connect,
3337 	.socketpair	= tipc_socketpair,
3338 	.accept		= sock_no_accept,
3339 	.getname	= tipc_getname,
3340 	.poll		= tipc_poll,
3341 	.ioctl		= tipc_ioctl,
3342 	.listen		= sock_no_listen,
3343 	.shutdown	= tipc_shutdown,
3344 	.setsockopt	= tipc_setsockopt,
3345 	.getsockopt	= tipc_getsockopt,
3346 	.sendmsg	= tipc_sendmsg,
3347 	.recvmsg	= tipc_recvmsg,
3348 	.mmap		= sock_no_mmap,
3349 	.sendpage	= sock_no_sendpage
3350 };
3351 
3352 static const struct proto_ops packet_ops = {
3353 	.owner		= THIS_MODULE,
3354 	.family		= AF_TIPC,
3355 	.release	= tipc_release,
3356 	.bind		= tipc_bind,
3357 	.connect	= tipc_connect,
3358 	.socketpair	= tipc_socketpair,
3359 	.accept		= tipc_accept,
3360 	.getname	= tipc_getname,
3361 	.poll		= tipc_poll,
3362 	.ioctl		= tipc_ioctl,
3363 	.listen		= tipc_listen,
3364 	.shutdown	= tipc_shutdown,
3365 	.setsockopt	= tipc_setsockopt,
3366 	.getsockopt	= tipc_getsockopt,
3367 	.sendmsg	= tipc_send_packet,
3368 	.recvmsg	= tipc_recvmsg,
3369 	.mmap		= sock_no_mmap,
3370 	.sendpage	= sock_no_sendpage
3371 };
3372 
3373 static const struct proto_ops stream_ops = {
3374 	.owner		= THIS_MODULE,
3375 	.family		= AF_TIPC,
3376 	.release	= tipc_release,
3377 	.bind		= tipc_bind,
3378 	.connect	= tipc_connect,
3379 	.socketpair	= tipc_socketpair,
3380 	.accept		= tipc_accept,
3381 	.getname	= tipc_getname,
3382 	.poll		= tipc_poll,
3383 	.ioctl		= tipc_ioctl,
3384 	.listen		= tipc_listen,
3385 	.shutdown	= tipc_shutdown,
3386 	.setsockopt	= tipc_setsockopt,
3387 	.getsockopt	= tipc_getsockopt,
3388 	.sendmsg	= tipc_sendstream,
3389 	.recvmsg	= tipc_recvstream,
3390 	.mmap		= sock_no_mmap,
3391 	.sendpage	= sock_no_sendpage
3392 };
3393 
3394 static const struct net_proto_family tipc_family_ops = {
3395 	.owner		= THIS_MODULE,
3396 	.family		= AF_TIPC,
3397 	.create		= tipc_sk_create
3398 };
3399 
3400 static struct proto tipc_proto = {
3401 	.name		= "TIPC",
3402 	.owner		= THIS_MODULE,
3403 	.obj_size	= sizeof(struct tipc_sock),
3404 	.sysctl_rmem	= sysctl_tipc_rmem
3405 };
3406 
3407 /**
3408  * tipc_socket_init - initialize TIPC socket interface
3409  *
3410  * Return: 0 on success, errno otherwise
3411  */
3412 int tipc_socket_init(void)
3413 {
3414 	int res;
3415 
3416 	res = proto_register(&tipc_proto, 1);
3417 	if (res) {
3418 		pr_err("Failed to register TIPC protocol type\n");
3419 		goto out;
3420 	}
3421 
3422 	res = sock_register(&tipc_family_ops);
3423 	if (res) {
3424 		pr_err("Failed to register TIPC socket type\n");
3425 		proto_unregister(&tipc_proto);
3426 		goto out;
3427 	}
3428  out:
3429 	return res;
3430 }
3431 
3432 /**
3433  * tipc_socket_stop - stop TIPC socket interface
3434  */
3435 void tipc_socket_stop(void)
3436 {
3437 	sock_unregister(tipc_family_ops.family);
3438 	proto_unregister(&tipc_proto);
3439 }
3440 
3441 /* Caller should hold socket lock for the passed tipc socket. */
3442 static int __tipc_nl_add_sk_con(struct sk_buff *skb, struct tipc_sock *tsk)
3443 {
3444 	u32 peer_node, peer_port;
3445 	u32 conn_type, conn_instance;
3446 	struct nlattr *nest;
3447 
3448 	peer_node = tsk_peer_node(tsk);
3449 	peer_port = tsk_peer_port(tsk);
3450 	conn_type = msg_nametype(&tsk->phdr);
3451 	conn_instance = msg_nameinst(&tsk->phdr);
3452 	nest = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_CON);
3453 	if (!nest)
3454 		return -EMSGSIZE;
3455 
3456 	if (nla_put_u32(skb, TIPC_NLA_CON_NODE, peer_node))
3457 		goto msg_full;
3458 	if (nla_put_u32(skb, TIPC_NLA_CON_SOCK, peer_port))
3459 		goto msg_full;
3460 
3461 	if (tsk->conn_addrtype != 0) {
3462 		if (nla_put_flag(skb, TIPC_NLA_CON_FLAG))
3463 			goto msg_full;
3464 		if (nla_put_u32(skb, TIPC_NLA_CON_TYPE, conn_type))
3465 			goto msg_full;
3466 		if (nla_put_u32(skb, TIPC_NLA_CON_INST, conn_instance))
3467 			goto msg_full;
3468 	}
3469 	nla_nest_end(skb, nest);
3470 
3471 	return 0;
3472 
3473 msg_full:
3474 	nla_nest_cancel(skb, nest);
3475 
3476 	return -EMSGSIZE;
3477 }
3478 
3479 static int __tipc_nl_add_sk_info(struct sk_buff *skb, struct tipc_sock
3480 			  *tsk)
3481 {
3482 	struct net *net = sock_net(skb->sk);
3483 	struct sock *sk = &tsk->sk;
3484 
3485 	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid) ||
3486 	    nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tipc_own_addr(net)))
3487 		return -EMSGSIZE;
3488 
3489 	if (tipc_sk_connected(sk)) {
3490 		if (__tipc_nl_add_sk_con(skb, tsk))
3491 			return -EMSGSIZE;
3492 	} else if (!list_empty(&tsk->publications)) {
3493 		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
3494 			return -EMSGSIZE;
3495 	}
3496 	return 0;
3497 }
3498 
3499 /* Caller should hold socket lock for the passed tipc socket. */
3500 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
3501 			    struct tipc_sock *tsk)
3502 {
3503 	struct nlattr *attrs;
3504 	void *hdr;
3505 
3506 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3507 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
3508 	if (!hdr)
3509 		goto msg_cancel;
3510 
3511 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3512 	if (!attrs)
3513 		goto genlmsg_cancel;
3514 
3515 	if (__tipc_nl_add_sk_info(skb, tsk))
3516 		goto attr_msg_cancel;
3517 
3518 	nla_nest_end(skb, attrs);
3519 	genlmsg_end(skb, hdr);
3520 
3521 	return 0;
3522 
3523 attr_msg_cancel:
3524 	nla_nest_cancel(skb, attrs);
3525 genlmsg_cancel:
3526 	genlmsg_cancel(skb, hdr);
3527 msg_cancel:
3528 	return -EMSGSIZE;
3529 }
3530 
3531 int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
3532 		    int (*skb_handler)(struct sk_buff *skb,
3533 				       struct netlink_callback *cb,
3534 				       struct tipc_sock *tsk))
3535 {
3536 	struct rhashtable_iter *iter = (void *)cb->args[4];
3537 	struct tipc_sock *tsk;
3538 	int err;
3539 
3540 	rhashtable_walk_start(iter);
3541 	while ((tsk = rhashtable_walk_next(iter)) != NULL) {
3542 		if (IS_ERR(tsk)) {
3543 			err = PTR_ERR(tsk);
3544 			if (err == -EAGAIN) {
3545 				err = 0;
3546 				continue;
3547 			}
3548 			break;
3549 		}
3550 
3551 		sock_hold(&tsk->sk);
3552 		rhashtable_walk_stop(iter);
3553 		lock_sock(&tsk->sk);
3554 		err = skb_handler(skb, cb, tsk);
3555 		if (err) {
3556 			release_sock(&tsk->sk);
3557 			sock_put(&tsk->sk);
3558 			goto out;
3559 		}
3560 		release_sock(&tsk->sk);
3561 		rhashtable_walk_start(iter);
3562 		sock_put(&tsk->sk);
3563 	}
3564 	rhashtable_walk_stop(iter);
3565 out:
3566 	return skb->len;
3567 }
3568 EXPORT_SYMBOL(tipc_nl_sk_walk);
3569 
3570 int tipc_dump_start(struct netlink_callback *cb)
3571 {
3572 	return __tipc_dump_start(cb, sock_net(cb->skb->sk));
3573 }
3574 EXPORT_SYMBOL(tipc_dump_start);
3575 
3576 int __tipc_dump_start(struct netlink_callback *cb, struct net *net)
3577 {
3578 	/* tipc_nl_name_table_dump() uses cb->args[0...3]. */
3579 	struct rhashtable_iter *iter = (void *)cb->args[4];
3580 	struct tipc_net *tn = tipc_net(net);
3581 
3582 	if (!iter) {
3583 		iter = kmalloc(sizeof(*iter), GFP_KERNEL);
3584 		if (!iter)
3585 			return -ENOMEM;
3586 
3587 		cb->args[4] = (long)iter;
3588 	}
3589 
3590 	rhashtable_walk_enter(&tn->sk_rht, iter);
3591 	return 0;
3592 }
3593 
3594 int tipc_dump_done(struct netlink_callback *cb)
3595 {
3596 	struct rhashtable_iter *hti = (void *)cb->args[4];
3597 
3598 	rhashtable_walk_exit(hti);
3599 	kfree(hti);
3600 	return 0;
3601 }
3602 EXPORT_SYMBOL(tipc_dump_done);
3603 
3604 int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct netlink_callback *cb,
3605 			   struct tipc_sock *tsk, u32 sk_filter_state,
3606 			   u64 (*tipc_diag_gen_cookie)(struct sock *sk))
3607 {
3608 	struct sock *sk = &tsk->sk;
3609 	struct nlattr *attrs;
3610 	struct nlattr *stat;
3611 
3612 	/*filter response w.r.t sk_state*/
3613 	if (!(sk_filter_state & (1 << sk->sk_state)))
3614 		return 0;
3615 
3616 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3617 	if (!attrs)
3618 		goto msg_cancel;
3619 
3620 	if (__tipc_nl_add_sk_info(skb, tsk))
3621 		goto attr_msg_cancel;
3622 
3623 	if (nla_put_u32(skb, TIPC_NLA_SOCK_TYPE, (u32)sk->sk_type) ||
3624 	    nla_put_u32(skb, TIPC_NLA_SOCK_TIPC_STATE, (u32)sk->sk_state) ||
3625 	    nla_put_u32(skb, TIPC_NLA_SOCK_INO, sock_i_ino(sk)) ||
3626 	    nla_put_u32(skb, TIPC_NLA_SOCK_UID,
3627 			from_kuid_munged(sk_user_ns(NETLINK_CB(cb->skb).sk),
3628 					 sock_i_uid(sk))) ||
3629 	    nla_put_u64_64bit(skb, TIPC_NLA_SOCK_COOKIE,
3630 			      tipc_diag_gen_cookie(sk),
3631 			      TIPC_NLA_SOCK_PAD))
3632 		goto attr_msg_cancel;
3633 
3634 	stat = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_STAT);
3635 	if (!stat)
3636 		goto attr_msg_cancel;
3637 
3638 	if (nla_put_u32(skb, TIPC_NLA_SOCK_STAT_RCVQ,
3639 			skb_queue_len(&sk->sk_receive_queue)) ||
3640 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_SENDQ,
3641 			skb_queue_len(&sk->sk_write_queue)) ||
3642 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_DROP,
3643 			atomic_read(&sk->sk_drops)))
3644 		goto stat_msg_cancel;
3645 
3646 	if (tsk->cong_link_cnt &&
3647 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_LINK_CONG))
3648 		goto stat_msg_cancel;
3649 
3650 	if (tsk_conn_cong(tsk) &&
3651 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_CONN_CONG))
3652 		goto stat_msg_cancel;
3653 
3654 	nla_nest_end(skb, stat);
3655 
3656 	if (tsk->group)
3657 		if (tipc_group_fill_sock_diag(tsk->group, skb))
3658 			goto stat_msg_cancel;
3659 
3660 	nla_nest_end(skb, attrs);
3661 
3662 	return 0;
3663 
3664 stat_msg_cancel:
3665 	nla_nest_cancel(skb, stat);
3666 attr_msg_cancel:
3667 	nla_nest_cancel(skb, attrs);
3668 msg_cancel:
3669 	return -EMSGSIZE;
3670 }
3671 EXPORT_SYMBOL(tipc_sk_fill_sock_diag);
3672 
3673 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
3674 {
3675 	return tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk);
3676 }
3677 
3678 /* Caller should hold socket lock for the passed tipc socket. */
3679 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
3680 				 struct netlink_callback *cb,
3681 				 struct publication *publ)
3682 {
3683 	void *hdr;
3684 	struct nlattr *attrs;
3685 
3686 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3687 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET);
3688 	if (!hdr)
3689 		goto msg_cancel;
3690 
3691 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_PUBL);
3692 	if (!attrs)
3693 		goto genlmsg_cancel;
3694 
3695 	if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key))
3696 		goto attr_msg_cancel;
3697 	if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->sr.type))
3698 		goto attr_msg_cancel;
3699 	if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->sr.lower))
3700 		goto attr_msg_cancel;
3701 	if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->sr.upper))
3702 		goto attr_msg_cancel;
3703 
3704 	nla_nest_end(skb, attrs);
3705 	genlmsg_end(skb, hdr);
3706 
3707 	return 0;
3708 
3709 attr_msg_cancel:
3710 	nla_nest_cancel(skb, attrs);
3711 genlmsg_cancel:
3712 	genlmsg_cancel(skb, hdr);
3713 msg_cancel:
3714 	return -EMSGSIZE;
3715 }
3716 
3717 /* Caller should hold socket lock for the passed tipc socket. */
3718 static int __tipc_nl_list_sk_publ(struct sk_buff *skb,
3719 				  struct netlink_callback *cb,
3720 				  struct tipc_sock *tsk, u32 *last_publ)
3721 {
3722 	int err;
3723 	struct publication *p;
3724 
3725 	if (*last_publ) {
3726 		list_for_each_entry(p, &tsk->publications, binding_sock) {
3727 			if (p->key == *last_publ)
3728 				break;
3729 		}
3730 		if (p->key != *last_publ) {
3731 			/* We never set seq or call nl_dump_check_consistent()
3732 			 * this means that setting prev_seq here will cause the
3733 			 * consistence check to fail in the netlink callback
3734 			 * handler. Resulting in the last NLMSG_DONE message
3735 			 * having the NLM_F_DUMP_INTR flag set.
3736 			 */
3737 			cb->prev_seq = 1;
3738 			*last_publ = 0;
3739 			return -EPIPE;
3740 		}
3741 	} else {
3742 		p = list_first_entry(&tsk->publications, struct publication,
3743 				     binding_sock);
3744 	}
3745 
3746 	list_for_each_entry_from(p, &tsk->publications, binding_sock) {
3747 		err = __tipc_nl_add_sk_publ(skb, cb, p);
3748 		if (err) {
3749 			*last_publ = p->key;
3750 			return err;
3751 		}
3752 	}
3753 	*last_publ = 0;
3754 
3755 	return 0;
3756 }
3757 
3758 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
3759 {
3760 	int err;
3761 	u32 tsk_portid = cb->args[0];
3762 	u32 last_publ = cb->args[1];
3763 	u32 done = cb->args[2];
3764 	struct net *net = sock_net(skb->sk);
3765 	struct tipc_sock *tsk;
3766 
3767 	if (!tsk_portid) {
3768 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
3769 		struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
3770 
3771 		if (!attrs[TIPC_NLA_SOCK])
3772 			return -EINVAL;
3773 
3774 		err = nla_parse_nested_deprecated(sock, TIPC_NLA_SOCK_MAX,
3775 						  attrs[TIPC_NLA_SOCK],
3776 						  tipc_nl_sock_policy, NULL);
3777 		if (err)
3778 			return err;
3779 
3780 		if (!sock[TIPC_NLA_SOCK_REF])
3781 			return -EINVAL;
3782 
3783 		tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
3784 	}
3785 
3786 	if (done)
3787 		return 0;
3788 
3789 	tsk = tipc_sk_lookup(net, tsk_portid);
3790 	if (!tsk)
3791 		return -EINVAL;
3792 
3793 	lock_sock(&tsk->sk);
3794 	err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ);
3795 	if (!err)
3796 		done = 1;
3797 	release_sock(&tsk->sk);
3798 	sock_put(&tsk->sk);
3799 
3800 	cb->args[0] = tsk_portid;
3801 	cb->args[1] = last_publ;
3802 	cb->args[2] = done;
3803 
3804 	return skb->len;
3805 }
3806 
3807 /**
3808  * tipc_sk_filtering - check if a socket should be traced
3809  * @sk: the socket to be examined
3810  *
3811  * @sysctl_tipc_sk_filter is used as the socket tuple for filtering:
3812  * (portid, sock type, name type, name lower, name upper)
3813  *
3814  * Return: true if the socket meets the socket tuple data
3815  * (value 0 = 'any') or when there is no tuple set (all = 0),
3816  * otherwise false
3817  */
3818 bool tipc_sk_filtering(struct sock *sk)
3819 {
3820 	struct tipc_sock *tsk;
3821 	struct publication *p;
3822 	u32 _port, _sktype, _type, _lower, _upper;
3823 	u32 type = 0, lower = 0, upper = 0;
3824 
3825 	if (!sk)
3826 		return true;
3827 
3828 	tsk = tipc_sk(sk);
3829 
3830 	_port = sysctl_tipc_sk_filter[0];
3831 	_sktype = sysctl_tipc_sk_filter[1];
3832 	_type = sysctl_tipc_sk_filter[2];
3833 	_lower = sysctl_tipc_sk_filter[3];
3834 	_upper = sysctl_tipc_sk_filter[4];
3835 
3836 	if (!_port && !_sktype && !_type && !_lower && !_upper)
3837 		return true;
3838 
3839 	if (_port)
3840 		return (_port == tsk->portid);
3841 
3842 	if (_sktype && _sktype != sk->sk_type)
3843 		return false;
3844 
3845 	if (tsk->published) {
3846 		p = list_first_entry_or_null(&tsk->publications,
3847 					     struct publication, binding_sock);
3848 		if (p) {
3849 			type = p->sr.type;
3850 			lower = p->sr.lower;
3851 			upper = p->sr.upper;
3852 		}
3853 	}
3854 
3855 	if (!tipc_sk_type_connectionless(sk)) {
3856 		type = msg_nametype(&tsk->phdr);
3857 		lower = msg_nameinst(&tsk->phdr);
3858 		upper = lower;
3859 	}
3860 
3861 	if ((_type && _type != type) || (_lower && _lower != lower) ||
3862 	    (_upper && _upper != upper))
3863 		return false;
3864 
3865 	return true;
3866 }
3867 
3868 u32 tipc_sock_get_portid(struct sock *sk)
3869 {
3870 	return (sk) ? (tipc_sk(sk))->portid : 0;
3871 }
3872 
3873 /**
3874  * tipc_sk_overlimit1 - check if socket rx queue is about to be overloaded,
3875  *			both the rcv and backlog queues are considered
3876  * @sk: tipc sk to be checked
3877  * @skb: tipc msg to be checked
3878  *
3879  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3880  */
3881 
3882 bool tipc_sk_overlimit1(struct sock *sk, struct sk_buff *skb)
3883 {
3884 	atomic_t *dcnt = &tipc_sk(sk)->dupl_rcvcnt;
3885 	unsigned int lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
3886 	unsigned int qsize = sk->sk_backlog.len + sk_rmem_alloc_get(sk);
3887 
3888 	return (qsize > lim * 90 / 100);
3889 }
3890 
3891 /**
3892  * tipc_sk_overlimit2 - check if socket rx queue is about to be overloaded,
3893  *			only the rcv queue is considered
3894  * @sk: tipc sk to be checked
3895  * @skb: tipc msg to be checked
3896  *
3897  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3898  */
3899 
3900 bool tipc_sk_overlimit2(struct sock *sk, struct sk_buff *skb)
3901 {
3902 	unsigned int lim = rcvbuf_limit(sk, skb);
3903 	unsigned int qsize = sk_rmem_alloc_get(sk);
3904 
3905 	return (qsize > lim * 90 / 100);
3906 }
3907 
3908 /**
3909  * tipc_sk_dump - dump TIPC socket
3910  * @sk: tipc sk to be dumped
3911  * @dqueues: bitmask to decide if any socket queue to be dumped?
3912  *           - TIPC_DUMP_NONE: don't dump socket queues
3913  *           - TIPC_DUMP_SK_SNDQ: dump socket send queue
3914  *           - TIPC_DUMP_SK_RCVQ: dump socket rcv queue
3915  *           - TIPC_DUMP_SK_BKLGQ: dump socket backlog queue
3916  *           - TIPC_DUMP_ALL: dump all the socket queues above
3917  * @buf: returned buffer of dump data in format
3918  */
3919 int tipc_sk_dump(struct sock *sk, u16 dqueues, char *buf)
3920 {
3921 	int i = 0;
3922 	size_t sz = (dqueues) ? SK_LMAX : SK_LMIN;
3923 	u32 conn_type, conn_instance;
3924 	struct tipc_sock *tsk;
3925 	struct publication *p;
3926 	bool tsk_connected;
3927 
3928 	if (!sk) {
3929 		i += scnprintf(buf, sz, "sk data: (null)\n");
3930 		return i;
3931 	}
3932 
3933 	tsk = tipc_sk(sk);
3934 	tsk_connected = !tipc_sk_type_connectionless(sk);
3935 
3936 	i += scnprintf(buf, sz, "sk data: %u", sk->sk_type);
3937 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_state);
3938 	i += scnprintf(buf + i, sz - i, " %x", tsk_own_node(tsk));
3939 	i += scnprintf(buf + i, sz - i, " %u", tsk->portid);
3940 	i += scnprintf(buf + i, sz - i, " | %u", tsk_connected);
3941 	if (tsk_connected) {
3942 		i += scnprintf(buf + i, sz - i, " %x", tsk_peer_node(tsk));
3943 		i += scnprintf(buf + i, sz - i, " %u", tsk_peer_port(tsk));
3944 		conn_type = msg_nametype(&tsk->phdr);
3945 		conn_instance = msg_nameinst(&tsk->phdr);
3946 		i += scnprintf(buf + i, sz - i, " %u", conn_type);
3947 		i += scnprintf(buf + i, sz - i, " %u", conn_instance);
3948 	}
3949 	i += scnprintf(buf + i, sz - i, " | %u", tsk->published);
3950 	if (tsk->published) {
3951 		p = list_first_entry_or_null(&tsk->publications,
3952 					     struct publication, binding_sock);
3953 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.type : 0);
3954 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.lower : 0);
3955 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.upper : 0);
3956 	}
3957 	i += scnprintf(buf + i, sz - i, " | %u", tsk->snd_win);
3958 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_win);
3959 	i += scnprintf(buf + i, sz - i, " %u", tsk->max_pkt);
3960 	i += scnprintf(buf + i, sz - i, " %x", tsk->peer_caps);
3961 	i += scnprintf(buf + i, sz - i, " %u", tsk->cong_link_cnt);
3962 	i += scnprintf(buf + i, sz - i, " %u", tsk->snt_unacked);
3963 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_unacked);
3964 	i += scnprintf(buf + i, sz - i, " %u", atomic_read(&tsk->dupl_rcvcnt));
3965 	i += scnprintf(buf + i, sz - i, " %u", sk->sk_shutdown);
3966 	i += scnprintf(buf + i, sz - i, " | %d", sk_wmem_alloc_get(sk));
3967 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_sndbuf);
3968 	i += scnprintf(buf + i, sz - i, " | %d", sk_rmem_alloc_get(sk));
3969 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_rcvbuf);
3970 	i += scnprintf(buf + i, sz - i, " | %d\n", READ_ONCE(sk->sk_backlog.len));
3971 
3972 	if (dqueues & TIPC_DUMP_SK_SNDQ) {
3973 		i += scnprintf(buf + i, sz - i, "sk_write_queue: ");
3974 		i += tipc_list_dump(&sk->sk_write_queue, false, buf + i);
3975 	}
3976 
3977 	if (dqueues & TIPC_DUMP_SK_RCVQ) {
3978 		i += scnprintf(buf + i, sz - i, "sk_receive_queue: ");
3979 		i += tipc_list_dump(&sk->sk_receive_queue, false, buf + i);
3980 	}
3981 
3982 	if (dqueues & TIPC_DUMP_SK_BKLGQ) {
3983 		i += scnprintf(buf + i, sz - i, "sk_backlog:\n  head ");
3984 		i += tipc_skb_dump(sk->sk_backlog.head, false, buf + i);
3985 		if (sk->sk_backlog.tail != sk->sk_backlog.head) {
3986 			i += scnprintf(buf + i, sz - i, "  tail ");
3987 			i += tipc_skb_dump(sk->sk_backlog.tail, false,
3988 					   buf + i);
3989 		}
3990 	}
3991 
3992 	return i;
3993 }
3994