xref: /linux/net/tipc/socket.c (revision 3c4fc7bf4c9e66fe71abcbf93f62f4ddb89b7f15)
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 		sk_free(sk);
506 		pr_warn("Socket create failed; port number exhausted\n");
507 		return -EINVAL;
508 	}
509 
510 	/* Ensure tsk is visible before we read own_addr. */
511 	smp_mb();
512 
513 	tipc_msg_init(tipc_own_addr(net), msg, TIPC_LOW_IMPORTANCE,
514 		      TIPC_NAMED_MSG, NAMED_H_SIZE, 0);
515 
516 	msg_set_origport(msg, tsk->portid);
517 	timer_setup(&sk->sk_timer, tipc_sk_timeout, 0);
518 	sk->sk_shutdown = 0;
519 	sk->sk_backlog_rcv = tipc_sk_backlog_rcv;
520 	sk->sk_rcvbuf = READ_ONCE(sysctl_tipc_rmem[1]);
521 	sk->sk_data_ready = tipc_data_ready;
522 	sk->sk_write_space = tipc_write_space;
523 	sk->sk_destruct = tipc_sock_destruct;
524 	tsk->conn_timeout = CONN_TIMEOUT_DEFAULT;
525 	tsk->group_is_open = true;
526 	atomic_set(&tsk->dupl_rcvcnt, 0);
527 
528 	/* Start out with safe limits until we receive an advertised window */
529 	tsk->snd_win = tsk_adv_blocks(RCVBUF_MIN);
530 	tsk->rcv_win = tsk->snd_win;
531 
532 	if (tipc_sk_type_connectionless(sk)) {
533 		tsk_set_unreturnable(tsk, true);
534 		if (sock->type == SOCK_DGRAM)
535 			tsk_set_unreliable(tsk, true);
536 	}
537 	__skb_queue_head_init(&tsk->mc_method.deferredq);
538 	trace_tipc_sk_create(sk, NULL, TIPC_DUMP_NONE, " ");
539 	return 0;
540 }
541 
542 static void tipc_sk_callback(struct rcu_head *head)
543 {
544 	struct tipc_sock *tsk = container_of(head, struct tipc_sock, rcu);
545 
546 	sock_put(&tsk->sk);
547 }
548 
549 /* Caller should hold socket lock for the socket. */
550 static void __tipc_shutdown(struct socket *sock, int error)
551 {
552 	struct sock *sk = sock->sk;
553 	struct tipc_sock *tsk = tipc_sk(sk);
554 	struct net *net = sock_net(sk);
555 	long timeout = msecs_to_jiffies(CONN_TIMEOUT_DEFAULT);
556 	u32 dnode = tsk_peer_node(tsk);
557 	struct sk_buff *skb;
558 
559 	/* Avoid that hi-prio shutdown msgs bypass msgs in link wakeup queue */
560 	tipc_wait_for_cond(sock, &timeout, (!tsk->cong_link_cnt &&
561 					    !tsk_conn_cong(tsk)));
562 
563 	/* Push out delayed messages if in Nagle mode */
564 	tipc_sk_push_backlog(tsk, false);
565 	/* Remove pending SYN */
566 	__skb_queue_purge(&sk->sk_write_queue);
567 
568 	/* Remove partially received buffer if any */
569 	skb = skb_peek(&sk->sk_receive_queue);
570 	if (skb && TIPC_SKB_CB(skb)->bytes_read) {
571 		__skb_unlink(skb, &sk->sk_receive_queue);
572 		kfree_skb(skb);
573 	}
574 
575 	/* Reject all unreceived messages if connectionless */
576 	if (tipc_sk_type_connectionless(sk)) {
577 		tsk_rej_rx_queue(sk, error);
578 		return;
579 	}
580 
581 	switch (sk->sk_state) {
582 	case TIPC_CONNECTING:
583 	case TIPC_ESTABLISHED:
584 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
585 		tipc_node_remove_conn(net, dnode, tsk->portid);
586 		/* Send a FIN+/- to its peer */
587 		skb = __skb_dequeue(&sk->sk_receive_queue);
588 		if (skb) {
589 			__skb_queue_purge(&sk->sk_receive_queue);
590 			tipc_sk_respond(sk, skb, error);
591 			break;
592 		}
593 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
594 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode,
595 				      tsk_own_node(tsk), tsk_peer_port(tsk),
596 				      tsk->portid, error);
597 		if (skb)
598 			tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
599 		break;
600 	case TIPC_LISTEN:
601 		/* Reject all SYN messages */
602 		tsk_rej_rx_queue(sk, error);
603 		break;
604 	default:
605 		__skb_queue_purge(&sk->sk_receive_queue);
606 		break;
607 	}
608 }
609 
610 /**
611  * tipc_release - destroy a TIPC socket
612  * @sock: socket to destroy
613  *
614  * This routine cleans up any messages that are still queued on the socket.
615  * For DGRAM and RDM socket types, all queued messages are rejected.
616  * For SEQPACKET and STREAM socket types, the first message is rejected
617  * and any others are discarded.  (If the first message on a STREAM socket
618  * is partially-read, it is discarded and the next one is rejected instead.)
619  *
620  * NOTE: Rejected messages are not necessarily returned to the sender!  They
621  * are returned or discarded according to the "destination droppable" setting
622  * specified for the message by the sender.
623  *
624  * Return: 0 on success, errno otherwise
625  */
626 static int tipc_release(struct socket *sock)
627 {
628 	struct sock *sk = sock->sk;
629 	struct tipc_sock *tsk;
630 
631 	/*
632 	 * Exit if socket isn't fully initialized (occurs when a failed accept()
633 	 * releases a pre-allocated child socket that was never used)
634 	 */
635 	if (sk == NULL)
636 		return 0;
637 
638 	tsk = tipc_sk(sk);
639 	lock_sock(sk);
640 
641 	trace_tipc_sk_release(sk, NULL, TIPC_DUMP_ALL, " ");
642 	__tipc_shutdown(sock, TIPC_ERR_NO_PORT);
643 	sk->sk_shutdown = SHUTDOWN_MASK;
644 	tipc_sk_leave(tsk);
645 	tipc_sk_withdraw(tsk, NULL);
646 	__skb_queue_purge(&tsk->mc_method.deferredq);
647 	sk_stop_timer(sk, &sk->sk_timer);
648 	tipc_sk_remove(tsk);
649 
650 	sock_orphan(sk);
651 	/* Reject any messages that accumulated in backlog queue */
652 	release_sock(sk);
653 	tipc_dest_list_purge(&tsk->cong_links);
654 	tsk->cong_link_cnt = 0;
655 	call_rcu(&tsk->rcu, tipc_sk_callback);
656 	sock->sk = NULL;
657 
658 	return 0;
659 }
660 
661 /**
662  * __tipc_bind - associate or disassocate TIPC name(s) with a socket
663  * @sock: socket structure
664  * @skaddr: socket address describing name(s) and desired operation
665  * @alen: size of socket address data structure
666  *
667  * Name and name sequence binding are indicated using a positive scope value;
668  * a negative scope value unbinds the specified name.  Specifying no name
669  * (i.e. a socket address length of 0) unbinds all names from the socket.
670  *
671  * Return: 0 on success, errno otherwise
672  *
673  * NOTE: This routine doesn't need to take the socket lock since it doesn't
674  *       access any non-constant socket information.
675  */
676 static int __tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
677 {
678 	struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr;
679 	struct tipc_sock *tsk = tipc_sk(sock->sk);
680 	bool unbind = false;
681 
682 	if (unlikely(!alen))
683 		return tipc_sk_withdraw(tsk, NULL);
684 
685 	if (ua->addrtype == TIPC_SERVICE_ADDR) {
686 		ua->addrtype = TIPC_SERVICE_RANGE;
687 		ua->sr.upper = ua->sr.lower;
688 	}
689 	if (ua->scope < 0) {
690 		unbind = true;
691 		ua->scope = -ua->scope;
692 	}
693 	/* Users may still use deprecated TIPC_ZONE_SCOPE */
694 	if (ua->scope != TIPC_NODE_SCOPE)
695 		ua->scope = TIPC_CLUSTER_SCOPE;
696 
697 	if (tsk->group)
698 		return -EACCES;
699 
700 	if (unbind)
701 		return tipc_sk_withdraw(tsk, ua);
702 	return tipc_sk_publish(tsk, ua);
703 }
704 
705 int tipc_sk_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
706 {
707 	int res;
708 
709 	lock_sock(sock->sk);
710 	res = __tipc_bind(sock, skaddr, alen);
711 	release_sock(sock->sk);
712 	return res;
713 }
714 
715 static int tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen)
716 {
717 	struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr;
718 	u32 atype = ua->addrtype;
719 
720 	if (alen) {
721 		if (!tipc_uaddr_valid(ua, alen))
722 			return -EINVAL;
723 		if (atype == TIPC_SOCKET_ADDR)
724 			return -EAFNOSUPPORT;
725 		if (ua->sr.type < TIPC_RESERVED_TYPES) {
726 			pr_warn_once("Can't bind to reserved service type %u\n",
727 				     ua->sr.type);
728 			return -EACCES;
729 		}
730 	}
731 	return tipc_sk_bind(sock, skaddr, alen);
732 }
733 
734 /**
735  * tipc_getname - get port ID of socket or peer socket
736  * @sock: socket structure
737  * @uaddr: area for returned socket address
738  * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
739  *
740  * Return: 0 on success, errno otherwise
741  *
742  * NOTE: This routine doesn't need to take the socket lock since it only
743  *       accesses socket information that is unchanging (or which changes in
744  *       a completely predictable manner).
745  */
746 static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
747 			int peer)
748 {
749 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
750 	struct sock *sk = sock->sk;
751 	struct tipc_sock *tsk = tipc_sk(sk);
752 
753 	memset(addr, 0, sizeof(*addr));
754 	if (peer) {
755 		if ((!tipc_sk_connected(sk)) &&
756 		    ((peer != 2) || (sk->sk_state != TIPC_DISCONNECTING)))
757 			return -ENOTCONN;
758 		addr->addr.id.ref = tsk_peer_port(tsk);
759 		addr->addr.id.node = tsk_peer_node(tsk);
760 	} else {
761 		addr->addr.id.ref = tsk->portid;
762 		addr->addr.id.node = tipc_own_addr(sock_net(sk));
763 	}
764 
765 	addr->addrtype = TIPC_SOCKET_ADDR;
766 	addr->family = AF_TIPC;
767 	addr->scope = 0;
768 	addr->addr.name.domain = 0;
769 
770 	return sizeof(*addr);
771 }
772 
773 /**
774  * tipc_poll - read and possibly block on pollmask
775  * @file: file structure associated with the socket
776  * @sock: socket for which to calculate the poll bits
777  * @wait: ???
778  *
779  * Return: pollmask value
780  *
781  * COMMENTARY:
782  * It appears that the usual socket locking mechanisms are not useful here
783  * since the pollmask info is potentially out-of-date the moment this routine
784  * exits.  TCP and other protocols seem to rely on higher level poll routines
785  * to handle any preventable race conditions, so TIPC will do the same ...
786  *
787  * IMPORTANT: The fact that a read or write operation is indicated does NOT
788  * imply that the operation will succeed, merely that it should be performed
789  * and will not block.
790  */
791 static __poll_t tipc_poll(struct file *file, struct socket *sock,
792 			      poll_table *wait)
793 {
794 	struct sock *sk = sock->sk;
795 	struct tipc_sock *tsk = tipc_sk(sk);
796 	__poll_t revents = 0;
797 
798 	sock_poll_wait(file, sock, wait);
799 	trace_tipc_sk_poll(sk, NULL, TIPC_DUMP_ALL, " ");
800 
801 	if (sk->sk_shutdown & RCV_SHUTDOWN)
802 		revents |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
803 	if (sk->sk_shutdown == SHUTDOWN_MASK)
804 		revents |= EPOLLHUP;
805 
806 	switch (sk->sk_state) {
807 	case TIPC_ESTABLISHED:
808 		if (!tsk->cong_link_cnt && !tsk_conn_cong(tsk))
809 			revents |= EPOLLOUT;
810 		fallthrough;
811 	case TIPC_LISTEN:
812 	case TIPC_CONNECTING:
813 		if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
814 			revents |= EPOLLIN | EPOLLRDNORM;
815 		break;
816 	case TIPC_OPEN:
817 		if (tsk->group_is_open && !tsk->cong_link_cnt)
818 			revents |= EPOLLOUT;
819 		if (!tipc_sk_type_connectionless(sk))
820 			break;
821 		if (skb_queue_empty_lockless(&sk->sk_receive_queue))
822 			break;
823 		revents |= EPOLLIN | EPOLLRDNORM;
824 		break;
825 	case TIPC_DISCONNECTING:
826 		revents = EPOLLIN | EPOLLRDNORM | EPOLLHUP;
827 		break;
828 	}
829 	return revents;
830 }
831 
832 /**
833  * tipc_sendmcast - send multicast message
834  * @sock: socket structure
835  * @ua: destination address struct
836  * @msg: message to send
837  * @dlen: length of data to send
838  * @timeout: timeout to wait for wakeup
839  *
840  * Called from function tipc_sendmsg(), which has done all sanity checks
841  * Return: the number of bytes sent on success, or errno
842  */
843 static int tipc_sendmcast(struct  socket *sock, struct tipc_uaddr *ua,
844 			  struct msghdr *msg, size_t dlen, long timeout)
845 {
846 	struct sock *sk = sock->sk;
847 	struct tipc_sock *tsk = tipc_sk(sk);
848 	struct tipc_msg *hdr = &tsk->phdr;
849 	struct net *net = sock_net(sk);
850 	int mtu = tipc_bcast_get_mtu(net);
851 	struct sk_buff_head pkts;
852 	struct tipc_nlist dsts;
853 	int rc;
854 
855 	if (tsk->group)
856 		return -EACCES;
857 
858 	/* Block or return if any destination link is congested */
859 	rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt);
860 	if (unlikely(rc))
861 		return rc;
862 
863 	/* Lookup destination nodes */
864 	tipc_nlist_init(&dsts, tipc_own_addr(net));
865 	tipc_nametbl_lookup_mcast_nodes(net, ua, &dsts);
866 	if (!dsts.local && !dsts.remote)
867 		return -EHOSTUNREACH;
868 
869 	/* Build message header */
870 	msg_set_type(hdr, TIPC_MCAST_MSG);
871 	msg_set_hdr_sz(hdr, MCAST_H_SIZE);
872 	msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE);
873 	msg_set_destport(hdr, 0);
874 	msg_set_destnode(hdr, 0);
875 	msg_set_nametype(hdr, ua->sr.type);
876 	msg_set_namelower(hdr, ua->sr.lower);
877 	msg_set_nameupper(hdr, ua->sr.upper);
878 
879 	/* Build message as chain of buffers */
880 	__skb_queue_head_init(&pkts);
881 	rc = tipc_msg_build(hdr, msg, 0, dlen, mtu, &pkts);
882 
883 	/* Send message if build was successful */
884 	if (unlikely(rc == dlen)) {
885 		trace_tipc_sk_sendmcast(sk, skb_peek(&pkts),
886 					TIPC_DUMP_SK_SNDQ, " ");
887 		rc = tipc_mcast_xmit(net, &pkts, &tsk->mc_method, &dsts,
888 				     &tsk->cong_link_cnt);
889 	}
890 
891 	tipc_nlist_purge(&dsts);
892 
893 	return rc ? rc : dlen;
894 }
895 
896 /**
897  * tipc_send_group_msg - send a message to a member in the group
898  * @net: network namespace
899  * @tsk: tipc socket
900  * @m: message to send
901  * @mb: group member
902  * @dnode: destination node
903  * @dport: destination port
904  * @dlen: total length of message data
905  */
906 static int tipc_send_group_msg(struct net *net, struct tipc_sock *tsk,
907 			       struct msghdr *m, struct tipc_member *mb,
908 			       u32 dnode, u32 dport, int dlen)
909 {
910 	u16 bc_snd_nxt = tipc_group_bc_snd_nxt(tsk->group);
911 	struct tipc_mc_method *method = &tsk->mc_method;
912 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
913 	struct tipc_msg *hdr = &tsk->phdr;
914 	struct sk_buff_head pkts;
915 	int mtu, rc;
916 
917 	/* Complete message header */
918 	msg_set_type(hdr, TIPC_GRP_UCAST_MSG);
919 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
920 	msg_set_destport(hdr, dport);
921 	msg_set_destnode(hdr, dnode);
922 	msg_set_grp_bc_seqno(hdr, bc_snd_nxt);
923 
924 	/* Build message as chain of buffers */
925 	__skb_queue_head_init(&pkts);
926 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid, false);
927 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
928 	if (unlikely(rc != dlen))
929 		return rc;
930 
931 	/* Send message */
932 	rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
933 	if (unlikely(rc == -ELINKCONG)) {
934 		tipc_dest_push(&tsk->cong_links, dnode, 0);
935 		tsk->cong_link_cnt++;
936 	}
937 
938 	/* Update send window */
939 	tipc_group_update_member(mb, blks);
940 
941 	/* A broadcast sent within next EXPIRE period must follow same path */
942 	method->rcast = true;
943 	method->mandatory = true;
944 	return dlen;
945 }
946 
947 /**
948  * tipc_send_group_unicast - send message to a member in the group
949  * @sock: socket structure
950  * @m: message to send
951  * @dlen: total length of message data
952  * @timeout: timeout to wait for wakeup
953  *
954  * Called from function tipc_sendmsg(), which has done all sanity checks
955  * Return: the number of bytes sent on success, or errno
956  */
957 static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m,
958 				   int dlen, long timeout)
959 {
960 	struct sock *sk = sock->sk;
961 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
962 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
963 	struct tipc_sock *tsk = tipc_sk(sk);
964 	struct net *net = sock_net(sk);
965 	struct tipc_member *mb = NULL;
966 	u32 node, port;
967 	int rc;
968 
969 	node = ua->sk.node;
970 	port = ua->sk.ref;
971 	if (!port && !node)
972 		return -EHOSTUNREACH;
973 
974 	/* Block or return if destination link or member is congested */
975 	rc = tipc_wait_for_cond(sock, &timeout,
976 				!tipc_dest_find(&tsk->cong_links, node, 0) &&
977 				tsk->group &&
978 				!tipc_group_cong(tsk->group, node, port, blks,
979 						 &mb));
980 	if (unlikely(rc))
981 		return rc;
982 
983 	if (unlikely(!mb))
984 		return -EHOSTUNREACH;
985 
986 	rc = tipc_send_group_msg(net, tsk, m, mb, node, port, dlen);
987 
988 	return rc ? rc : dlen;
989 }
990 
991 /**
992  * tipc_send_group_anycast - send message to any member with given identity
993  * @sock: socket structure
994  * @m: message to send
995  * @dlen: total length of message data
996  * @timeout: timeout to wait for wakeup
997  *
998  * Called from function tipc_sendmsg(), which has done all sanity checks
999  * Return: the number of bytes sent on success, or errno
1000  */
1001 static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
1002 				   int dlen, long timeout)
1003 {
1004 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1005 	struct sock *sk = sock->sk;
1006 	struct tipc_sock *tsk = tipc_sk(sk);
1007 	struct list_head *cong_links = &tsk->cong_links;
1008 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
1009 	struct tipc_msg *hdr = &tsk->phdr;
1010 	struct tipc_member *first = NULL;
1011 	struct tipc_member *mbr = NULL;
1012 	struct net *net = sock_net(sk);
1013 	u32 node, port, exclude;
1014 	struct list_head dsts;
1015 	int lookups = 0;
1016 	int dstcnt, rc;
1017 	bool cong;
1018 
1019 	INIT_LIST_HEAD(&dsts);
1020 	ua->sa.type = msg_nametype(hdr);
1021 	ua->scope = msg_lookup_scope(hdr);
1022 
1023 	while (++lookups < 4) {
1024 		exclude = tipc_group_exclude(tsk->group);
1025 
1026 		first = NULL;
1027 
1028 		/* Look for a non-congested destination member, if any */
1029 		while (1) {
1030 			if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt,
1031 						       exclude, false))
1032 				return -EHOSTUNREACH;
1033 			tipc_dest_pop(&dsts, &node, &port);
1034 			cong = tipc_group_cong(tsk->group, node, port, blks,
1035 					       &mbr);
1036 			if (!cong)
1037 				break;
1038 			if (mbr == first)
1039 				break;
1040 			if (!first)
1041 				first = mbr;
1042 		}
1043 
1044 		/* Start over if destination was not in member list */
1045 		if (unlikely(!mbr))
1046 			continue;
1047 
1048 		if (likely(!cong && !tipc_dest_find(cong_links, node, 0)))
1049 			break;
1050 
1051 		/* Block or return if destination link or member is congested */
1052 		rc = tipc_wait_for_cond(sock, &timeout,
1053 					!tipc_dest_find(cong_links, node, 0) &&
1054 					tsk->group &&
1055 					!tipc_group_cong(tsk->group, node, port,
1056 							 blks, &mbr));
1057 		if (unlikely(rc))
1058 			return rc;
1059 
1060 		/* Send, unless destination disappeared while waiting */
1061 		if (likely(mbr))
1062 			break;
1063 	}
1064 
1065 	if (unlikely(lookups >= 4))
1066 		return -EHOSTUNREACH;
1067 
1068 	rc = tipc_send_group_msg(net, tsk, m, mbr, node, port, dlen);
1069 
1070 	return rc ? rc : dlen;
1071 }
1072 
1073 /**
1074  * tipc_send_group_bcast - send message to all members in communication group
1075  * @sock: socket structure
1076  * @m: message to send
1077  * @dlen: total length of message data
1078  * @timeout: timeout to wait for wakeup
1079  *
1080  * Called from function tipc_sendmsg(), which has done all sanity checks
1081  * Return: the number of bytes sent on success, or errno
1082  */
1083 static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
1084 				 int dlen, long timeout)
1085 {
1086 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1087 	struct sock *sk = sock->sk;
1088 	struct net *net = sock_net(sk);
1089 	struct tipc_sock *tsk = tipc_sk(sk);
1090 	struct tipc_nlist *dsts;
1091 	struct tipc_mc_method *method = &tsk->mc_method;
1092 	bool ack = method->mandatory && method->rcast;
1093 	int blks = tsk_blocks(MCAST_H_SIZE + dlen);
1094 	struct tipc_msg *hdr = &tsk->phdr;
1095 	int mtu = tipc_bcast_get_mtu(net);
1096 	struct sk_buff_head pkts;
1097 	int rc = -EHOSTUNREACH;
1098 
1099 	/* Block or return if any destination link or member is congested */
1100 	rc = tipc_wait_for_cond(sock, &timeout,
1101 				!tsk->cong_link_cnt && tsk->group &&
1102 				!tipc_group_bc_cong(tsk->group, blks));
1103 	if (unlikely(rc))
1104 		return rc;
1105 
1106 	dsts = tipc_group_dests(tsk->group);
1107 	if (!dsts->local && !dsts->remote)
1108 		return -EHOSTUNREACH;
1109 
1110 	/* Complete message header */
1111 	if (ua) {
1112 		msg_set_type(hdr, TIPC_GRP_MCAST_MSG);
1113 		msg_set_nameinst(hdr, ua->sa.instance);
1114 	} else {
1115 		msg_set_type(hdr, TIPC_GRP_BCAST_MSG);
1116 		msg_set_nameinst(hdr, 0);
1117 	}
1118 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
1119 	msg_set_destport(hdr, 0);
1120 	msg_set_destnode(hdr, 0);
1121 	msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(tsk->group));
1122 
1123 	/* Avoid getting stuck with repeated forced replicasts */
1124 	msg_set_grp_bc_ack_req(hdr, ack);
1125 
1126 	/* Build message as chain of buffers */
1127 	__skb_queue_head_init(&pkts);
1128 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1129 	if (unlikely(rc != dlen))
1130 		return rc;
1131 
1132 	/* Send message */
1133 	rc = tipc_mcast_xmit(net, &pkts, method, dsts, &tsk->cong_link_cnt);
1134 	if (unlikely(rc))
1135 		return rc;
1136 
1137 	/* Update broadcast sequence number and send windows */
1138 	tipc_group_update_bc_members(tsk->group, blks, ack);
1139 
1140 	/* Broadcast link is now free to choose method for next broadcast */
1141 	method->mandatory = false;
1142 	method->expires = jiffies;
1143 
1144 	return dlen;
1145 }
1146 
1147 /**
1148  * tipc_send_group_mcast - send message to all members with given identity
1149  * @sock: socket structure
1150  * @m: message to send
1151  * @dlen: total length of message data
1152  * @timeout: timeout to wait for wakeup
1153  *
1154  * Called from function tipc_sendmsg(), which has done all sanity checks
1155  * Return: the number of bytes sent on success, or errno
1156  */
1157 static int tipc_send_group_mcast(struct socket *sock, struct msghdr *m,
1158 				 int dlen, long timeout)
1159 {
1160 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1161 	struct sock *sk = sock->sk;
1162 	struct tipc_sock *tsk = tipc_sk(sk);
1163 	struct tipc_group *grp = tsk->group;
1164 	struct tipc_msg *hdr = &tsk->phdr;
1165 	struct net *net = sock_net(sk);
1166 	struct list_head dsts;
1167 	u32 dstcnt, exclude;
1168 
1169 	INIT_LIST_HEAD(&dsts);
1170 	ua->sa.type = msg_nametype(hdr);
1171 	ua->scope = msg_lookup_scope(hdr);
1172 	exclude = tipc_group_exclude(grp);
1173 
1174 	if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt, exclude, true))
1175 		return -EHOSTUNREACH;
1176 
1177 	if (dstcnt == 1) {
1178 		tipc_dest_pop(&dsts, &ua->sk.node, &ua->sk.ref);
1179 		return tipc_send_group_unicast(sock, m, dlen, timeout);
1180 	}
1181 
1182 	tipc_dest_list_purge(&dsts);
1183 	return tipc_send_group_bcast(sock, m, dlen, timeout);
1184 }
1185 
1186 /**
1187  * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets
1188  * @net: the associated network namespace
1189  * @arrvq: queue with arriving messages, to be cloned after destination lookup
1190  * @inputq: queue with cloned messages, delivered to socket after dest lookup
1191  *
1192  * Multi-threaded: parallel calls with reference to same queues may occur
1193  */
1194 void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
1195 		       struct sk_buff_head *inputq)
1196 {
1197 	u32 self = tipc_own_addr(net);
1198 	struct sk_buff *skb, *_skb;
1199 	u32 portid, onode;
1200 	struct sk_buff_head tmpq;
1201 	struct list_head dports;
1202 	struct tipc_msg *hdr;
1203 	struct tipc_uaddr ua;
1204 	int user, mtyp, hlen;
1205 
1206 	__skb_queue_head_init(&tmpq);
1207 	INIT_LIST_HEAD(&dports);
1208 	ua.addrtype = TIPC_SERVICE_RANGE;
1209 
1210 	/* tipc_skb_peek() increments the head skb's reference counter */
1211 	skb = tipc_skb_peek(arrvq, &inputq->lock);
1212 	for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) {
1213 		hdr = buf_msg(skb);
1214 		user = msg_user(hdr);
1215 		mtyp = msg_type(hdr);
1216 		hlen = skb_headroom(skb) + msg_hdr_sz(hdr);
1217 		onode = msg_orignode(hdr);
1218 		ua.sr.type = msg_nametype(hdr);
1219 		ua.sr.lower = msg_namelower(hdr);
1220 		ua.sr.upper = msg_nameupper(hdr);
1221 		if (onode == self)
1222 			ua.scope = TIPC_ANY_SCOPE;
1223 		else
1224 			ua.scope = TIPC_CLUSTER_SCOPE;
1225 
1226 		if (mtyp == TIPC_GRP_UCAST_MSG || user == GROUP_PROTOCOL) {
1227 			spin_lock_bh(&inputq->lock);
1228 			if (skb_peek(arrvq) == skb) {
1229 				__skb_dequeue(arrvq);
1230 				__skb_queue_tail(inputq, skb);
1231 			}
1232 			kfree_skb(skb);
1233 			spin_unlock_bh(&inputq->lock);
1234 			continue;
1235 		}
1236 
1237 		/* Group messages require exact scope match */
1238 		if (msg_in_group(hdr)) {
1239 			ua.sr.lower = 0;
1240 			ua.sr.upper = ~0;
1241 			ua.scope = msg_lookup_scope(hdr);
1242 		}
1243 
1244 		/* Create destination port list: */
1245 		tipc_nametbl_lookup_mcast_sockets(net, &ua, &dports);
1246 
1247 		/* Clone message per destination */
1248 		while (tipc_dest_pop(&dports, NULL, &portid)) {
1249 			_skb = __pskb_copy(skb, hlen, GFP_ATOMIC);
1250 			if (_skb) {
1251 				msg_set_destport(buf_msg(_skb), portid);
1252 				__skb_queue_tail(&tmpq, _skb);
1253 				continue;
1254 			}
1255 			pr_warn("Failed to clone mcast rcv buffer\n");
1256 		}
1257 		/* Append clones to inputq only if skb is still head of arrvq */
1258 		spin_lock_bh(&inputq->lock);
1259 		if (skb_peek(arrvq) == skb) {
1260 			skb_queue_splice_tail_init(&tmpq, inputq);
1261 			/* Decrement the skb's refcnt */
1262 			kfree_skb(__skb_dequeue(arrvq));
1263 		}
1264 		spin_unlock_bh(&inputq->lock);
1265 		__skb_queue_purge(&tmpq);
1266 		kfree_skb(skb);
1267 	}
1268 	tipc_sk_rcv(net, inputq);
1269 }
1270 
1271 /* tipc_sk_push_backlog(): send accumulated buffers in socket write queue
1272  *                         when socket is in Nagle mode
1273  */
1274 static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack)
1275 {
1276 	struct sk_buff_head *txq = &tsk->sk.sk_write_queue;
1277 	struct sk_buff *skb = skb_peek_tail(txq);
1278 	struct net *net = sock_net(&tsk->sk);
1279 	u32 dnode = tsk_peer_node(tsk);
1280 	int rc;
1281 
1282 	if (nagle_ack) {
1283 		tsk->pkt_cnt += skb_queue_len(txq);
1284 		if (!tsk->pkt_cnt || tsk->msg_acc / tsk->pkt_cnt < 2) {
1285 			tsk->oneway = 0;
1286 			if (tsk->nagle_start < NAGLE_START_MAX)
1287 				tsk->nagle_start *= 2;
1288 			tsk->expect_ack = false;
1289 			pr_debug("tsk %10u: bad nagle %u -> %u, next start %u!\n",
1290 				 tsk->portid, tsk->msg_acc, tsk->pkt_cnt,
1291 				 tsk->nagle_start);
1292 		} else {
1293 			tsk->nagle_start = NAGLE_START_INIT;
1294 			if (skb) {
1295 				msg_set_ack_required(buf_msg(skb));
1296 				tsk->expect_ack = true;
1297 			} else {
1298 				tsk->expect_ack = false;
1299 			}
1300 		}
1301 		tsk->msg_acc = 0;
1302 		tsk->pkt_cnt = 0;
1303 	}
1304 
1305 	if (!skb || tsk->cong_link_cnt)
1306 		return;
1307 
1308 	/* Do not send SYN again after congestion */
1309 	if (msg_is_syn(buf_msg(skb)))
1310 		return;
1311 
1312 	if (tsk->msg_acc)
1313 		tsk->pkt_cnt += skb_queue_len(txq);
1314 	tsk->snt_unacked += tsk->snd_backlog;
1315 	tsk->snd_backlog = 0;
1316 	rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1317 	if (rc == -ELINKCONG)
1318 		tsk->cong_link_cnt = 1;
1319 }
1320 
1321 /**
1322  * tipc_sk_conn_proto_rcv - receive a connection mng protocol message
1323  * @tsk: receiving socket
1324  * @skb: pointer to message buffer.
1325  * @inputq: buffer list containing the buffers
1326  * @xmitq: output message area
1327  */
1328 static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb,
1329 				   struct sk_buff_head *inputq,
1330 				   struct sk_buff_head *xmitq)
1331 {
1332 	struct tipc_msg *hdr = buf_msg(skb);
1333 	u32 onode = tsk_own_node(tsk);
1334 	struct sock *sk = &tsk->sk;
1335 	int mtyp = msg_type(hdr);
1336 	bool was_cong;
1337 
1338 	/* Ignore if connection cannot be validated: */
1339 	if (!tsk_peer_msg(tsk, hdr)) {
1340 		trace_tipc_sk_drop_msg(sk, skb, TIPC_DUMP_NONE, "@proto_rcv!");
1341 		goto exit;
1342 	}
1343 
1344 	if (unlikely(msg_errcode(hdr))) {
1345 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1346 		tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
1347 				      tsk_peer_port(tsk));
1348 		sk->sk_state_change(sk);
1349 
1350 		/* State change is ignored if socket already awake,
1351 		 * - convert msg to abort msg and add to inqueue
1352 		 */
1353 		msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE);
1354 		msg_set_type(hdr, TIPC_CONN_MSG);
1355 		msg_set_size(hdr, BASIC_H_SIZE);
1356 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1357 		__skb_queue_tail(inputq, skb);
1358 		return;
1359 	}
1360 
1361 	tsk->probe_unacked = false;
1362 
1363 	if (mtyp == CONN_PROBE) {
1364 		msg_set_type(hdr, CONN_PROBE_REPLY);
1365 		if (tipc_msg_reverse(onode, &skb, TIPC_OK))
1366 			__skb_queue_tail(xmitq, skb);
1367 		return;
1368 	} else if (mtyp == CONN_ACK) {
1369 		was_cong = tsk_conn_cong(tsk);
1370 		tipc_sk_push_backlog(tsk, msg_nagle_ack(hdr));
1371 		tsk->snt_unacked -= msg_conn_ack(hdr);
1372 		if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1373 			tsk->snd_win = msg_adv_win(hdr);
1374 		if (was_cong && !tsk_conn_cong(tsk))
1375 			sk->sk_write_space(sk);
1376 	} else if (mtyp != CONN_PROBE_REPLY) {
1377 		pr_warn("Received unknown CONN_PROTO msg\n");
1378 	}
1379 exit:
1380 	kfree_skb(skb);
1381 }
1382 
1383 /**
1384  * tipc_sendmsg - send message in connectionless manner
1385  * @sock: socket structure
1386  * @m: message to send
1387  * @dsz: amount of user data to be sent
1388  *
1389  * Message must have an destination specified explicitly.
1390  * Used for SOCK_RDM and SOCK_DGRAM messages,
1391  * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
1392  * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
1393  *
1394  * Return: the number of bytes sent on success, or errno otherwise
1395  */
1396 static int tipc_sendmsg(struct socket *sock,
1397 			struct msghdr *m, size_t dsz)
1398 {
1399 	struct sock *sk = sock->sk;
1400 	int ret;
1401 
1402 	lock_sock(sk);
1403 	ret = __tipc_sendmsg(sock, m, dsz);
1404 	release_sock(sk);
1405 
1406 	return ret;
1407 }
1408 
1409 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
1410 {
1411 	struct sock *sk = sock->sk;
1412 	struct net *net = sock_net(sk);
1413 	struct tipc_sock *tsk = tipc_sk(sk);
1414 	struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name;
1415 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1416 	struct list_head *clinks = &tsk->cong_links;
1417 	bool syn = !tipc_sk_type_connectionless(sk);
1418 	struct tipc_group *grp = tsk->group;
1419 	struct tipc_msg *hdr = &tsk->phdr;
1420 	struct tipc_socket_addr skaddr;
1421 	struct sk_buff_head pkts;
1422 	int atype, mtu, rc;
1423 
1424 	if (unlikely(dlen > TIPC_MAX_USER_MSG_SIZE))
1425 		return -EMSGSIZE;
1426 
1427 	if (ua) {
1428 		if (!tipc_uaddr_valid(ua, m->msg_namelen))
1429 			return -EINVAL;
1430 		atype = ua->addrtype;
1431 	}
1432 
1433 	/* If socket belongs to a communication group follow other paths */
1434 	if (grp) {
1435 		if (!ua)
1436 			return tipc_send_group_bcast(sock, m, dlen, timeout);
1437 		if (atype == TIPC_SERVICE_ADDR)
1438 			return tipc_send_group_anycast(sock, m, dlen, timeout);
1439 		if (atype == TIPC_SOCKET_ADDR)
1440 			return tipc_send_group_unicast(sock, m, dlen, timeout);
1441 		if (atype == TIPC_SERVICE_RANGE)
1442 			return tipc_send_group_mcast(sock, m, dlen, timeout);
1443 		return -EINVAL;
1444 	}
1445 
1446 	if (!ua) {
1447 		ua = (struct tipc_uaddr *)&tsk->peer;
1448 		if (!syn && ua->family != AF_TIPC)
1449 			return -EDESTADDRREQ;
1450 		atype = ua->addrtype;
1451 	}
1452 
1453 	if (unlikely(syn)) {
1454 		if (sk->sk_state == TIPC_LISTEN)
1455 			return -EPIPE;
1456 		if (sk->sk_state != TIPC_OPEN)
1457 			return -EISCONN;
1458 		if (tsk->published)
1459 			return -EOPNOTSUPP;
1460 		if (atype == TIPC_SERVICE_ADDR)
1461 			tsk->conn_addrtype = atype;
1462 		msg_set_syn(hdr, 1);
1463 	}
1464 
1465 	memset(&skaddr, 0, sizeof(skaddr));
1466 
1467 	/* Determine destination */
1468 	if (atype == TIPC_SERVICE_RANGE) {
1469 		return tipc_sendmcast(sock, ua, m, dlen, timeout);
1470 	} else if (atype == TIPC_SERVICE_ADDR) {
1471 		skaddr.node = ua->lookup_node;
1472 		ua->scope = tipc_node2scope(skaddr.node);
1473 		if (!tipc_nametbl_lookup_anycast(net, ua, &skaddr))
1474 			return -EHOSTUNREACH;
1475 	} else if (atype == TIPC_SOCKET_ADDR) {
1476 		skaddr = ua->sk;
1477 	} else {
1478 		return -EINVAL;
1479 	}
1480 
1481 	/* Block or return if destination link is congested */
1482 	rc = tipc_wait_for_cond(sock, &timeout,
1483 				!tipc_dest_find(clinks, skaddr.node, 0));
1484 	if (unlikely(rc))
1485 		return rc;
1486 
1487 	/* Finally build message header */
1488 	msg_set_destnode(hdr, skaddr.node);
1489 	msg_set_destport(hdr, skaddr.ref);
1490 	if (atype == TIPC_SERVICE_ADDR) {
1491 		msg_set_type(hdr, TIPC_NAMED_MSG);
1492 		msg_set_hdr_sz(hdr, NAMED_H_SIZE);
1493 		msg_set_nametype(hdr, ua->sa.type);
1494 		msg_set_nameinst(hdr, ua->sa.instance);
1495 		msg_set_lookup_scope(hdr, ua->scope);
1496 	} else { /* TIPC_SOCKET_ADDR */
1497 		msg_set_type(hdr, TIPC_DIRECT_MSG);
1498 		msg_set_lookup_scope(hdr, 0);
1499 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1500 	}
1501 
1502 	/* Add message body */
1503 	__skb_queue_head_init(&pkts);
1504 	mtu = tipc_node_get_mtu(net, skaddr.node, tsk->portid, true);
1505 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1506 	if (unlikely(rc != dlen))
1507 		return rc;
1508 	if (unlikely(syn && !tipc_msg_skb_clone(&pkts, &sk->sk_write_queue))) {
1509 		__skb_queue_purge(&pkts);
1510 		return -ENOMEM;
1511 	}
1512 
1513 	/* Send message */
1514 	trace_tipc_sk_sendmsg(sk, skb_peek(&pkts), TIPC_DUMP_SK_SNDQ, " ");
1515 	rc = tipc_node_xmit(net, &pkts, skaddr.node, tsk->portid);
1516 	if (unlikely(rc == -ELINKCONG)) {
1517 		tipc_dest_push(clinks, skaddr.node, 0);
1518 		tsk->cong_link_cnt++;
1519 		rc = 0;
1520 	}
1521 
1522 	if (unlikely(syn && !rc)) {
1523 		tipc_set_sk_state(sk, TIPC_CONNECTING);
1524 		if (dlen && timeout) {
1525 			timeout = msecs_to_jiffies(timeout);
1526 			tipc_wait_for_connect(sock, &timeout);
1527 		}
1528 	}
1529 
1530 	return rc ? rc : dlen;
1531 }
1532 
1533 /**
1534  * tipc_sendstream - send stream-oriented data
1535  * @sock: socket structure
1536  * @m: data to send
1537  * @dsz: total length of data to be transmitted
1538  *
1539  * Used for SOCK_STREAM data.
1540  *
1541  * Return: the number of bytes sent on success (or partial success),
1542  * or errno if no data sent
1543  */
1544 static int tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz)
1545 {
1546 	struct sock *sk = sock->sk;
1547 	int ret;
1548 
1549 	lock_sock(sk);
1550 	ret = __tipc_sendstream(sock, m, dsz);
1551 	release_sock(sk);
1552 
1553 	return ret;
1554 }
1555 
1556 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dlen)
1557 {
1558 	struct sock *sk = sock->sk;
1559 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1560 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1561 	struct sk_buff_head *txq = &sk->sk_write_queue;
1562 	struct tipc_sock *tsk = tipc_sk(sk);
1563 	struct tipc_msg *hdr = &tsk->phdr;
1564 	struct net *net = sock_net(sk);
1565 	struct sk_buff *skb;
1566 	u32 dnode = tsk_peer_node(tsk);
1567 	int maxnagle = tsk->maxnagle;
1568 	int maxpkt = tsk->max_pkt;
1569 	int send, sent = 0;
1570 	int blocks, rc = 0;
1571 
1572 	if (unlikely(dlen > INT_MAX))
1573 		return -EMSGSIZE;
1574 
1575 	/* Handle implicit connection setup */
1576 	if (unlikely(dest && sk->sk_state == TIPC_OPEN)) {
1577 		rc = __tipc_sendmsg(sock, m, dlen);
1578 		if (dlen && dlen == rc) {
1579 			tsk->peer_caps = tipc_node_get_capabilities(net, dnode);
1580 			tsk->snt_unacked = tsk_inc(tsk, dlen + msg_hdr_sz(hdr));
1581 		}
1582 		return rc;
1583 	}
1584 
1585 	do {
1586 		rc = tipc_wait_for_cond(sock, &timeout,
1587 					(!tsk->cong_link_cnt &&
1588 					 !tsk_conn_cong(tsk) &&
1589 					 tipc_sk_connected(sk)));
1590 		if (unlikely(rc))
1591 			break;
1592 		send = min_t(size_t, dlen - sent, TIPC_MAX_USER_MSG_SIZE);
1593 		blocks = tsk->snd_backlog;
1594 		if (tsk->oneway++ >= tsk->nagle_start && maxnagle &&
1595 		    send <= maxnagle) {
1596 			rc = tipc_msg_append(hdr, m, send, maxnagle, txq);
1597 			if (unlikely(rc < 0))
1598 				break;
1599 			blocks += rc;
1600 			tsk->msg_acc++;
1601 			if (blocks <= 64 && tsk->expect_ack) {
1602 				tsk->snd_backlog = blocks;
1603 				sent += send;
1604 				break;
1605 			} else if (blocks > 64) {
1606 				tsk->pkt_cnt += skb_queue_len(txq);
1607 			} else {
1608 				skb = skb_peek_tail(txq);
1609 				if (skb) {
1610 					msg_set_ack_required(buf_msg(skb));
1611 					tsk->expect_ack = true;
1612 				} else {
1613 					tsk->expect_ack = false;
1614 				}
1615 				tsk->msg_acc = 0;
1616 				tsk->pkt_cnt = 0;
1617 			}
1618 		} else {
1619 			rc = tipc_msg_build(hdr, m, sent, send, maxpkt, txq);
1620 			if (unlikely(rc != send))
1621 				break;
1622 			blocks += tsk_inc(tsk, send + MIN_H_SIZE);
1623 		}
1624 		trace_tipc_sk_sendstream(sk, skb_peek(txq),
1625 					 TIPC_DUMP_SK_SNDQ, " ");
1626 		rc = tipc_node_xmit(net, txq, dnode, tsk->portid);
1627 		if (unlikely(rc == -ELINKCONG)) {
1628 			tsk->cong_link_cnt = 1;
1629 			rc = 0;
1630 		}
1631 		if (likely(!rc)) {
1632 			tsk->snt_unacked += blocks;
1633 			tsk->snd_backlog = 0;
1634 			sent += send;
1635 		}
1636 	} while (sent < dlen && !rc);
1637 
1638 	return sent ? sent : rc;
1639 }
1640 
1641 /**
1642  * tipc_send_packet - send a connection-oriented message
1643  * @sock: socket structure
1644  * @m: message to send
1645  * @dsz: length of data to be transmitted
1646  *
1647  * Used for SOCK_SEQPACKET messages.
1648  *
1649  * Return: the number of bytes sent on success, or errno otherwise
1650  */
1651 static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz)
1652 {
1653 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
1654 		return -EMSGSIZE;
1655 
1656 	return tipc_sendstream(sock, m, dsz);
1657 }
1658 
1659 /* tipc_sk_finish_conn - complete the setup of a connection
1660  */
1661 static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port,
1662 				u32 peer_node)
1663 {
1664 	struct sock *sk = &tsk->sk;
1665 	struct net *net = sock_net(sk);
1666 	struct tipc_msg *msg = &tsk->phdr;
1667 
1668 	msg_set_syn(msg, 0);
1669 	msg_set_destnode(msg, peer_node);
1670 	msg_set_destport(msg, peer_port);
1671 	msg_set_type(msg, TIPC_CONN_MSG);
1672 	msg_set_lookup_scope(msg, 0);
1673 	msg_set_hdr_sz(msg, SHORT_H_SIZE);
1674 
1675 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
1676 	tipc_set_sk_state(sk, TIPC_ESTABLISHED);
1677 	tipc_node_add_conn(net, peer_node, tsk->portid, peer_port);
1678 	tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid, true);
1679 	tsk->peer_caps = tipc_node_get_capabilities(net, peer_node);
1680 	tsk_set_nagle(tsk);
1681 	__skb_queue_purge(&sk->sk_write_queue);
1682 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1683 		return;
1684 
1685 	/* Fall back to message based flow control */
1686 	tsk->rcv_win = FLOWCTL_MSG_WIN;
1687 	tsk->snd_win = FLOWCTL_MSG_WIN;
1688 }
1689 
1690 /**
1691  * tipc_sk_set_orig_addr - capture sender's address for received message
1692  * @m: descriptor for message info
1693  * @skb: received message
1694  *
1695  * Note: Address is not captured if not requested by receiver.
1696  */
1697 static void tipc_sk_set_orig_addr(struct msghdr *m, struct sk_buff *skb)
1698 {
1699 	DECLARE_SOCKADDR(struct sockaddr_pair *, srcaddr, m->msg_name);
1700 	struct tipc_msg *hdr = buf_msg(skb);
1701 
1702 	if (!srcaddr)
1703 		return;
1704 
1705 	srcaddr->sock.family = AF_TIPC;
1706 	srcaddr->sock.addrtype = TIPC_SOCKET_ADDR;
1707 	srcaddr->sock.scope = 0;
1708 	srcaddr->sock.addr.id.ref = msg_origport(hdr);
1709 	srcaddr->sock.addr.id.node = msg_orignode(hdr);
1710 	srcaddr->sock.addr.name.domain = 0;
1711 	m->msg_namelen = sizeof(struct sockaddr_tipc);
1712 
1713 	if (!msg_in_group(hdr))
1714 		return;
1715 
1716 	/* Group message users may also want to know sending member's id */
1717 	srcaddr->member.family = AF_TIPC;
1718 	srcaddr->member.addrtype = TIPC_SERVICE_ADDR;
1719 	srcaddr->member.scope = 0;
1720 	srcaddr->member.addr.name.name.type = msg_nametype(hdr);
1721 	srcaddr->member.addr.name.name.instance = TIPC_SKB_CB(skb)->orig_member;
1722 	srcaddr->member.addr.name.domain = 0;
1723 	m->msg_namelen = sizeof(*srcaddr);
1724 }
1725 
1726 /**
1727  * tipc_sk_anc_data_recv - optionally capture ancillary data for received message
1728  * @m: descriptor for message info
1729  * @skb: received message buffer
1730  * @tsk: TIPC port associated with message
1731  *
1732  * Note: Ancillary data is not captured if not requested by receiver.
1733  *
1734  * Return: 0 if successful, otherwise errno
1735  */
1736 static int tipc_sk_anc_data_recv(struct msghdr *m, struct sk_buff *skb,
1737 				 struct tipc_sock *tsk)
1738 {
1739 	struct tipc_msg *hdr;
1740 	u32 data[3] = {0,};
1741 	bool has_addr;
1742 	int dlen, rc;
1743 
1744 	if (likely(m->msg_controllen == 0))
1745 		return 0;
1746 
1747 	hdr = buf_msg(skb);
1748 	dlen = msg_data_sz(hdr);
1749 
1750 	/* Capture errored message object, if any */
1751 	if (msg_errcode(hdr)) {
1752 		if (skb_linearize(skb))
1753 			return -ENOMEM;
1754 		hdr = buf_msg(skb);
1755 		data[0] = msg_errcode(hdr);
1756 		data[1] = dlen;
1757 		rc = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, data);
1758 		if (rc || !dlen)
1759 			return rc;
1760 		rc = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, dlen, msg_data(hdr));
1761 		if (rc)
1762 			return rc;
1763 	}
1764 
1765 	/* Capture TIPC_SERVICE_ADDR/RANGE destination address, if any */
1766 	switch (msg_type(hdr)) {
1767 	case TIPC_NAMED_MSG:
1768 		has_addr = true;
1769 		data[0] = msg_nametype(hdr);
1770 		data[1] = msg_namelower(hdr);
1771 		data[2] = data[1];
1772 		break;
1773 	case TIPC_MCAST_MSG:
1774 		has_addr = true;
1775 		data[0] = msg_nametype(hdr);
1776 		data[1] = msg_namelower(hdr);
1777 		data[2] = msg_nameupper(hdr);
1778 		break;
1779 	case TIPC_CONN_MSG:
1780 		has_addr = !!tsk->conn_addrtype;
1781 		data[0] = msg_nametype(&tsk->phdr);
1782 		data[1] = msg_nameinst(&tsk->phdr);
1783 		data[2] = data[1];
1784 		break;
1785 	default:
1786 		has_addr = false;
1787 	}
1788 	if (!has_addr)
1789 		return 0;
1790 	return put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, data);
1791 }
1792 
1793 static struct sk_buff *tipc_sk_build_ack(struct tipc_sock *tsk)
1794 {
1795 	struct sock *sk = &tsk->sk;
1796 	struct sk_buff *skb = NULL;
1797 	struct tipc_msg *msg;
1798 	u32 peer_port = tsk_peer_port(tsk);
1799 	u32 dnode = tsk_peer_node(tsk);
1800 
1801 	if (!tipc_sk_connected(sk))
1802 		return NULL;
1803 	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
1804 			      dnode, tsk_own_node(tsk), peer_port,
1805 			      tsk->portid, TIPC_OK);
1806 	if (!skb)
1807 		return NULL;
1808 	msg = buf_msg(skb);
1809 	msg_set_conn_ack(msg, tsk->rcv_unacked);
1810 	tsk->rcv_unacked = 0;
1811 
1812 	/* Adjust to and advertize the correct window limit */
1813 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) {
1814 		tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf);
1815 		msg_set_adv_win(msg, tsk->rcv_win);
1816 	}
1817 	return skb;
1818 }
1819 
1820 static void tipc_sk_send_ack(struct tipc_sock *tsk)
1821 {
1822 	struct sk_buff *skb;
1823 
1824 	skb = tipc_sk_build_ack(tsk);
1825 	if (!skb)
1826 		return;
1827 
1828 	tipc_node_xmit_skb(sock_net(&tsk->sk), skb, tsk_peer_node(tsk),
1829 			   msg_link_selector(buf_msg(skb)));
1830 }
1831 
1832 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
1833 {
1834 	struct sock *sk = sock->sk;
1835 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1836 	long timeo = *timeop;
1837 	int err = sock_error(sk);
1838 
1839 	if (err)
1840 		return err;
1841 
1842 	for (;;) {
1843 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1844 			if (sk->sk_shutdown & RCV_SHUTDOWN) {
1845 				err = -ENOTCONN;
1846 				break;
1847 			}
1848 			add_wait_queue(sk_sleep(sk), &wait);
1849 			release_sock(sk);
1850 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
1851 			sched_annotate_sleep();
1852 			lock_sock(sk);
1853 			remove_wait_queue(sk_sleep(sk), &wait);
1854 		}
1855 		err = 0;
1856 		if (!skb_queue_empty(&sk->sk_receive_queue))
1857 			break;
1858 		err = -EAGAIN;
1859 		if (!timeo)
1860 			break;
1861 		err = sock_intr_errno(timeo);
1862 		if (signal_pending(current))
1863 			break;
1864 
1865 		err = sock_error(sk);
1866 		if (err)
1867 			break;
1868 	}
1869 	*timeop = timeo;
1870 	return err;
1871 }
1872 
1873 /**
1874  * tipc_recvmsg - receive packet-oriented message
1875  * @sock: network socket
1876  * @m: descriptor for message info
1877  * @buflen: length of user buffer area
1878  * @flags: receive flags
1879  *
1880  * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1881  * If the complete message doesn't fit in user area, truncate it.
1882  *
1883  * Return: size of returned message data, errno otherwise
1884  */
1885 static int tipc_recvmsg(struct socket *sock, struct msghdr *m,
1886 			size_t buflen,	int flags)
1887 {
1888 	struct sock *sk = sock->sk;
1889 	bool connected = !tipc_sk_type_connectionless(sk);
1890 	struct tipc_sock *tsk = tipc_sk(sk);
1891 	int rc, err, hlen, dlen, copy;
1892 	struct tipc_skb_cb *skb_cb;
1893 	struct sk_buff_head xmitq;
1894 	struct tipc_msg *hdr;
1895 	struct sk_buff *skb;
1896 	bool grp_evt;
1897 	long timeout;
1898 
1899 	/* Catch invalid receive requests */
1900 	if (unlikely(!buflen))
1901 		return -EINVAL;
1902 
1903 	lock_sock(sk);
1904 	if (unlikely(connected && sk->sk_state == TIPC_OPEN)) {
1905 		rc = -ENOTCONN;
1906 		goto exit;
1907 	}
1908 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1909 
1910 	/* Step rcv queue to first msg with data or error; wait if necessary */
1911 	do {
1912 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
1913 		if (unlikely(rc))
1914 			goto exit;
1915 		skb = skb_peek(&sk->sk_receive_queue);
1916 		skb_cb = TIPC_SKB_CB(skb);
1917 		hdr = buf_msg(skb);
1918 		dlen = msg_data_sz(hdr);
1919 		hlen = msg_hdr_sz(hdr);
1920 		err = msg_errcode(hdr);
1921 		grp_evt = msg_is_grp_evt(hdr);
1922 		if (likely(dlen || err))
1923 			break;
1924 		tsk_advance_rx_queue(sk);
1925 	} while (1);
1926 
1927 	/* Collect msg meta data, including error code and rejected data */
1928 	tipc_sk_set_orig_addr(m, skb);
1929 	rc = tipc_sk_anc_data_recv(m, skb, tsk);
1930 	if (unlikely(rc))
1931 		goto exit;
1932 	hdr = buf_msg(skb);
1933 
1934 	/* Capture data if non-error msg, otherwise just set return value */
1935 	if (likely(!err)) {
1936 		int offset = skb_cb->bytes_read;
1937 
1938 		copy = min_t(int, dlen - offset, buflen);
1939 		rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
1940 		if (unlikely(rc))
1941 			goto exit;
1942 		if (unlikely(offset + copy < dlen)) {
1943 			if (flags & MSG_EOR) {
1944 				if (!(flags & MSG_PEEK))
1945 					skb_cb->bytes_read = offset + copy;
1946 			} else {
1947 				m->msg_flags |= MSG_TRUNC;
1948 				skb_cb->bytes_read = 0;
1949 			}
1950 		} else {
1951 			if (flags & MSG_EOR)
1952 				m->msg_flags |= MSG_EOR;
1953 			skb_cb->bytes_read = 0;
1954 		}
1955 	} else {
1956 		copy = 0;
1957 		rc = 0;
1958 		if (err != TIPC_CONN_SHUTDOWN && connected && !m->msg_control) {
1959 			rc = -ECONNRESET;
1960 			goto exit;
1961 		}
1962 	}
1963 
1964 	/* Mark message as group event if applicable */
1965 	if (unlikely(grp_evt)) {
1966 		if (msg_grp_evt(hdr) == TIPC_WITHDRAWN)
1967 			m->msg_flags |= MSG_EOR;
1968 		m->msg_flags |= MSG_OOB;
1969 		copy = 0;
1970 	}
1971 
1972 	/* Caption of data or error code/rejected data was successful */
1973 	if (unlikely(flags & MSG_PEEK))
1974 		goto exit;
1975 
1976 	/* Send group flow control advertisement when applicable */
1977 	if (tsk->group && msg_in_group(hdr) && !grp_evt) {
1978 		__skb_queue_head_init(&xmitq);
1979 		tipc_group_update_rcv_win(tsk->group, tsk_blocks(hlen + dlen),
1980 					  msg_orignode(hdr), msg_origport(hdr),
1981 					  &xmitq);
1982 		tipc_node_distr_xmit(sock_net(sk), &xmitq);
1983 	}
1984 
1985 	if (skb_cb->bytes_read)
1986 		goto exit;
1987 
1988 	tsk_advance_rx_queue(sk);
1989 
1990 	if (likely(!connected))
1991 		goto exit;
1992 
1993 	/* Send connection flow control advertisement when applicable */
1994 	tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
1995 	if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
1996 		tipc_sk_send_ack(tsk);
1997 exit:
1998 	release_sock(sk);
1999 	return rc ? rc : copy;
2000 }
2001 
2002 /**
2003  * tipc_recvstream - receive stream-oriented data
2004  * @sock: network socket
2005  * @m: descriptor for message info
2006  * @buflen: total size of user buffer area
2007  * @flags: receive flags
2008  *
2009  * Used for SOCK_STREAM messages only.  If not enough data is available
2010  * will optionally wait for more; never truncates data.
2011  *
2012  * Return: size of returned message data, errno otherwise
2013  */
2014 static int tipc_recvstream(struct socket *sock, struct msghdr *m,
2015 			   size_t buflen, int flags)
2016 {
2017 	struct sock *sk = sock->sk;
2018 	struct tipc_sock *tsk = tipc_sk(sk);
2019 	struct sk_buff *skb;
2020 	struct tipc_msg *hdr;
2021 	struct tipc_skb_cb *skb_cb;
2022 	bool peek = flags & MSG_PEEK;
2023 	int offset, required, copy, copied = 0;
2024 	int hlen, dlen, err, rc;
2025 	long timeout;
2026 
2027 	/* Catch invalid receive attempts */
2028 	if (unlikely(!buflen))
2029 		return -EINVAL;
2030 
2031 	lock_sock(sk);
2032 
2033 	if (unlikely(sk->sk_state == TIPC_OPEN)) {
2034 		rc = -ENOTCONN;
2035 		goto exit;
2036 	}
2037 	required = sock_rcvlowat(sk, flags & MSG_WAITALL, buflen);
2038 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
2039 
2040 	do {
2041 		/* Look at first msg in receive queue; wait if necessary */
2042 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
2043 		if (unlikely(rc))
2044 			break;
2045 		skb = skb_peek(&sk->sk_receive_queue);
2046 		skb_cb = TIPC_SKB_CB(skb);
2047 		hdr = buf_msg(skb);
2048 		dlen = msg_data_sz(hdr);
2049 		hlen = msg_hdr_sz(hdr);
2050 		err = msg_errcode(hdr);
2051 
2052 		/* Discard any empty non-errored (SYN-) message */
2053 		if (unlikely(!dlen && !err)) {
2054 			tsk_advance_rx_queue(sk);
2055 			continue;
2056 		}
2057 
2058 		/* Collect msg meta data, incl. error code and rejected data */
2059 		if (!copied) {
2060 			tipc_sk_set_orig_addr(m, skb);
2061 			rc = tipc_sk_anc_data_recv(m, skb, tsk);
2062 			if (rc)
2063 				break;
2064 			hdr = buf_msg(skb);
2065 		}
2066 
2067 		/* Copy data if msg ok, otherwise return error/partial data */
2068 		if (likely(!err)) {
2069 			offset = skb_cb->bytes_read;
2070 			copy = min_t(int, dlen - offset, buflen - copied);
2071 			rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
2072 			if (unlikely(rc))
2073 				break;
2074 			copied += copy;
2075 			offset += copy;
2076 			if (unlikely(offset < dlen)) {
2077 				if (!peek)
2078 					skb_cb->bytes_read = offset;
2079 				break;
2080 			}
2081 		} else {
2082 			rc = 0;
2083 			if ((err != TIPC_CONN_SHUTDOWN) && !m->msg_control)
2084 				rc = -ECONNRESET;
2085 			if (copied || rc)
2086 				break;
2087 		}
2088 
2089 		if (unlikely(peek))
2090 			break;
2091 
2092 		tsk_advance_rx_queue(sk);
2093 
2094 		/* Send connection flow control advertisement when applicable */
2095 		tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
2096 		if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
2097 			tipc_sk_send_ack(tsk);
2098 
2099 		/* Exit if all requested data or FIN/error received */
2100 		if (copied == buflen || err)
2101 			break;
2102 
2103 	} while (!skb_queue_empty(&sk->sk_receive_queue) || copied < required);
2104 exit:
2105 	release_sock(sk);
2106 	return copied ? copied : rc;
2107 }
2108 
2109 /**
2110  * tipc_write_space - wake up thread if port congestion is released
2111  * @sk: socket
2112  */
2113 static void tipc_write_space(struct sock *sk)
2114 {
2115 	struct socket_wq *wq;
2116 
2117 	rcu_read_lock();
2118 	wq = rcu_dereference(sk->sk_wq);
2119 	if (skwq_has_sleeper(wq))
2120 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2121 						EPOLLWRNORM | EPOLLWRBAND);
2122 	rcu_read_unlock();
2123 }
2124 
2125 /**
2126  * tipc_data_ready - wake up threads to indicate messages have been received
2127  * @sk: socket
2128  */
2129 static void tipc_data_ready(struct sock *sk)
2130 {
2131 	struct socket_wq *wq;
2132 
2133 	rcu_read_lock();
2134 	wq = rcu_dereference(sk->sk_wq);
2135 	if (skwq_has_sleeper(wq))
2136 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
2137 						EPOLLRDNORM | EPOLLRDBAND);
2138 	rcu_read_unlock();
2139 }
2140 
2141 static void tipc_sock_destruct(struct sock *sk)
2142 {
2143 	__skb_queue_purge(&sk->sk_receive_queue);
2144 }
2145 
2146 static void tipc_sk_proto_rcv(struct sock *sk,
2147 			      struct sk_buff_head *inputq,
2148 			      struct sk_buff_head *xmitq)
2149 {
2150 	struct sk_buff *skb = __skb_dequeue(inputq);
2151 	struct tipc_sock *tsk = tipc_sk(sk);
2152 	struct tipc_msg *hdr = buf_msg(skb);
2153 	struct tipc_group *grp = tsk->group;
2154 	bool wakeup = false;
2155 
2156 	switch (msg_user(hdr)) {
2157 	case CONN_MANAGER:
2158 		tipc_sk_conn_proto_rcv(tsk, skb, inputq, xmitq);
2159 		return;
2160 	case SOCK_WAKEUP:
2161 		tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0);
2162 		/* coupled with smp_rmb() in tipc_wait_for_cond() */
2163 		smp_wmb();
2164 		tsk->cong_link_cnt--;
2165 		wakeup = true;
2166 		tipc_sk_push_backlog(tsk, false);
2167 		break;
2168 	case GROUP_PROTOCOL:
2169 		tipc_group_proto_rcv(grp, &wakeup, hdr, inputq, xmitq);
2170 		break;
2171 	case TOP_SRV:
2172 		tipc_group_member_evt(tsk->group, &wakeup, &sk->sk_rcvbuf,
2173 				      hdr, inputq, xmitq);
2174 		break;
2175 	default:
2176 		break;
2177 	}
2178 
2179 	if (wakeup)
2180 		sk->sk_write_space(sk);
2181 
2182 	kfree_skb(skb);
2183 }
2184 
2185 /**
2186  * tipc_sk_filter_connect - check incoming message for a connection-based socket
2187  * @tsk: TIPC socket
2188  * @skb: pointer to message buffer.
2189  * @xmitq: for Nagle ACK if any
2190  * Return: true if message should be added to receive queue, false otherwise
2191  */
2192 static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb,
2193 				   struct sk_buff_head *xmitq)
2194 {
2195 	struct sock *sk = &tsk->sk;
2196 	struct net *net = sock_net(sk);
2197 	struct tipc_msg *hdr = buf_msg(skb);
2198 	bool con_msg = msg_connected(hdr);
2199 	u32 pport = tsk_peer_port(tsk);
2200 	u32 pnode = tsk_peer_node(tsk);
2201 	u32 oport = msg_origport(hdr);
2202 	u32 onode = msg_orignode(hdr);
2203 	int err = msg_errcode(hdr);
2204 	unsigned long delay;
2205 
2206 	if (unlikely(msg_mcast(hdr)))
2207 		return false;
2208 	tsk->oneway = 0;
2209 
2210 	switch (sk->sk_state) {
2211 	case TIPC_CONNECTING:
2212 		/* Setup ACK */
2213 		if (likely(con_msg)) {
2214 			if (err)
2215 				break;
2216 			tipc_sk_finish_conn(tsk, oport, onode);
2217 			msg_set_importance(&tsk->phdr, msg_importance(hdr));
2218 			/* ACK+ message with data is added to receive queue */
2219 			if (msg_data_sz(hdr))
2220 				return true;
2221 			/* Empty ACK-, - wake up sleeping connect() and drop */
2222 			sk->sk_state_change(sk);
2223 			msg_set_dest_droppable(hdr, 1);
2224 			return false;
2225 		}
2226 		/* Ignore connectionless message if not from listening socket */
2227 		if (oport != pport || onode != pnode)
2228 			return false;
2229 
2230 		/* Rejected SYN */
2231 		if (err != TIPC_ERR_OVERLOAD)
2232 			break;
2233 
2234 		/* Prepare for new setup attempt if we have a SYN clone */
2235 		if (skb_queue_empty(&sk->sk_write_queue))
2236 			break;
2237 		get_random_bytes(&delay, 2);
2238 		delay %= (tsk->conn_timeout / 4);
2239 		delay = msecs_to_jiffies(delay + 100);
2240 		sk_reset_timer(sk, &sk->sk_timer, jiffies + delay);
2241 		return false;
2242 	case TIPC_OPEN:
2243 	case TIPC_DISCONNECTING:
2244 		return false;
2245 	case TIPC_LISTEN:
2246 		/* Accept only SYN message */
2247 		if (!msg_is_syn(hdr) &&
2248 		    tipc_node_get_capabilities(net, onode) & TIPC_SYN_BIT)
2249 			return false;
2250 		if (!con_msg && !err)
2251 			return true;
2252 		return false;
2253 	case TIPC_ESTABLISHED:
2254 		if (!skb_queue_empty(&sk->sk_write_queue))
2255 			tipc_sk_push_backlog(tsk, false);
2256 		/* Accept only connection-based messages sent by peer */
2257 		if (likely(con_msg && !err && pport == oport &&
2258 			   pnode == onode)) {
2259 			if (msg_ack_required(hdr)) {
2260 				struct sk_buff *skb;
2261 
2262 				skb = tipc_sk_build_ack(tsk);
2263 				if (skb) {
2264 					msg_set_nagle_ack(buf_msg(skb));
2265 					__skb_queue_tail(xmitq, skb);
2266 				}
2267 			}
2268 			return true;
2269 		}
2270 		if (!tsk_peer_msg(tsk, hdr))
2271 			return false;
2272 		if (!err)
2273 			return true;
2274 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2275 		tipc_node_remove_conn(net, pnode, tsk->portid);
2276 		sk->sk_state_change(sk);
2277 		return true;
2278 	default:
2279 		pr_err("Unknown sk_state %u\n", sk->sk_state);
2280 	}
2281 	/* Abort connection setup attempt */
2282 	tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2283 	sk->sk_err = ECONNREFUSED;
2284 	sk->sk_state_change(sk);
2285 	return true;
2286 }
2287 
2288 /**
2289  * rcvbuf_limit - get proper overload limit of socket receive queue
2290  * @sk: socket
2291  * @skb: message
2292  *
2293  * For connection oriented messages, irrespective of importance,
2294  * default queue limit is 2 MB.
2295  *
2296  * For connectionless messages, queue limits are based on message
2297  * importance as follows:
2298  *
2299  * TIPC_LOW_IMPORTANCE       (2 MB)
2300  * TIPC_MEDIUM_IMPORTANCE    (4 MB)
2301  * TIPC_HIGH_IMPORTANCE      (8 MB)
2302  * TIPC_CRITICAL_IMPORTANCE  (16 MB)
2303  *
2304  * Return: overload limit according to corresponding message importance
2305  */
2306 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb)
2307 {
2308 	struct tipc_sock *tsk = tipc_sk(sk);
2309 	struct tipc_msg *hdr = buf_msg(skb);
2310 
2311 	if (unlikely(msg_in_group(hdr)))
2312 		return READ_ONCE(sk->sk_rcvbuf);
2313 
2314 	if (unlikely(!msg_connected(hdr)))
2315 		return READ_ONCE(sk->sk_rcvbuf) << msg_importance(hdr);
2316 
2317 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
2318 		return READ_ONCE(sk->sk_rcvbuf);
2319 
2320 	return FLOWCTL_MSG_LIM;
2321 }
2322 
2323 /**
2324  * tipc_sk_filter_rcv - validate incoming message
2325  * @sk: socket
2326  * @skb: pointer to message.
2327  * @xmitq: output message area (FIXME)
2328  *
2329  * Enqueues message on receive queue if acceptable; optionally handles
2330  * disconnect indication for a connected socket.
2331  *
2332  * Called with socket lock already taken
2333  */
2334 static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb,
2335 			       struct sk_buff_head *xmitq)
2336 {
2337 	bool sk_conn = !tipc_sk_type_connectionless(sk);
2338 	struct tipc_sock *tsk = tipc_sk(sk);
2339 	struct tipc_group *grp = tsk->group;
2340 	struct tipc_msg *hdr = buf_msg(skb);
2341 	struct net *net = sock_net(sk);
2342 	struct sk_buff_head inputq;
2343 	int mtyp = msg_type(hdr);
2344 	int limit, err = TIPC_OK;
2345 
2346 	trace_tipc_sk_filter_rcv(sk, skb, TIPC_DUMP_ALL, " ");
2347 	TIPC_SKB_CB(skb)->bytes_read = 0;
2348 	__skb_queue_head_init(&inputq);
2349 	__skb_queue_tail(&inputq, skb);
2350 
2351 	if (unlikely(!msg_isdata(hdr)))
2352 		tipc_sk_proto_rcv(sk, &inputq, xmitq);
2353 
2354 	if (unlikely(grp))
2355 		tipc_group_filter_msg(grp, &inputq, xmitq);
2356 
2357 	if (unlikely(!grp) && mtyp == TIPC_MCAST_MSG)
2358 		tipc_mcast_filter_msg(net, &tsk->mc_method.deferredq, &inputq);
2359 
2360 	/* Validate and add to receive buffer if there is space */
2361 	while ((skb = __skb_dequeue(&inputq))) {
2362 		hdr = buf_msg(skb);
2363 		limit = rcvbuf_limit(sk, skb);
2364 		if ((sk_conn && !tipc_sk_filter_connect(tsk, skb, xmitq)) ||
2365 		    (!sk_conn && msg_connected(hdr)) ||
2366 		    (!grp && msg_in_group(hdr)))
2367 			err = TIPC_ERR_NO_PORT;
2368 		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit) {
2369 			trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL,
2370 					   "err_overload2!");
2371 			atomic_inc(&sk->sk_drops);
2372 			err = TIPC_ERR_OVERLOAD;
2373 		}
2374 
2375 		if (unlikely(err)) {
2376 			if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) {
2377 				trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE,
2378 						      "@filter_rcv!");
2379 				__skb_queue_tail(xmitq, skb);
2380 			}
2381 			err = TIPC_OK;
2382 			continue;
2383 		}
2384 		__skb_queue_tail(&sk->sk_receive_queue, skb);
2385 		skb_set_owner_r(skb, sk);
2386 		trace_tipc_sk_overlimit2(sk, skb, TIPC_DUMP_ALL,
2387 					 "rcvq >90% allocated!");
2388 		sk->sk_data_ready(sk);
2389 	}
2390 }
2391 
2392 /**
2393  * tipc_sk_backlog_rcv - handle incoming message from backlog queue
2394  * @sk: socket
2395  * @skb: message
2396  *
2397  * Caller must hold socket lock
2398  */
2399 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
2400 {
2401 	unsigned int before = sk_rmem_alloc_get(sk);
2402 	struct sk_buff_head xmitq;
2403 	unsigned int added;
2404 
2405 	__skb_queue_head_init(&xmitq);
2406 
2407 	tipc_sk_filter_rcv(sk, skb, &xmitq);
2408 	added = sk_rmem_alloc_get(sk) - before;
2409 	atomic_add(added, &tipc_sk(sk)->dupl_rcvcnt);
2410 
2411 	/* Send pending response/rejected messages, if any */
2412 	tipc_node_distr_xmit(sock_net(sk), &xmitq);
2413 	return 0;
2414 }
2415 
2416 /**
2417  * tipc_sk_enqueue - extract all buffers with destination 'dport' from
2418  *                   inputq and try adding them to socket or backlog queue
2419  * @inputq: list of incoming buffers with potentially different destinations
2420  * @sk: socket where the buffers should be enqueued
2421  * @dport: port number for the socket
2422  * @xmitq: output queue
2423  *
2424  * Caller must hold socket lock
2425  */
2426 static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
2427 			    u32 dport, struct sk_buff_head *xmitq)
2428 {
2429 	unsigned long time_limit = jiffies + usecs_to_jiffies(20000);
2430 	struct sk_buff *skb;
2431 	unsigned int lim;
2432 	atomic_t *dcnt;
2433 	u32 onode;
2434 
2435 	while (skb_queue_len(inputq)) {
2436 		if (unlikely(time_after_eq(jiffies, time_limit)))
2437 			return;
2438 
2439 		skb = tipc_skb_dequeue(inputq, dport);
2440 		if (unlikely(!skb))
2441 			return;
2442 
2443 		/* Add message directly to receive queue if possible */
2444 		if (!sock_owned_by_user(sk)) {
2445 			tipc_sk_filter_rcv(sk, skb, xmitq);
2446 			continue;
2447 		}
2448 
2449 		/* Try backlog, compensating for double-counted bytes */
2450 		dcnt = &tipc_sk(sk)->dupl_rcvcnt;
2451 		if (!sk->sk_backlog.len)
2452 			atomic_set(dcnt, 0);
2453 		lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
2454 		if (likely(!sk_add_backlog(sk, skb, lim))) {
2455 			trace_tipc_sk_overlimit1(sk, skb, TIPC_DUMP_ALL,
2456 						 "bklg & rcvq >90% allocated!");
2457 			continue;
2458 		}
2459 
2460 		trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL, "err_overload!");
2461 		/* Overload => reject message back to sender */
2462 		onode = tipc_own_addr(sock_net(sk));
2463 		atomic_inc(&sk->sk_drops);
2464 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD)) {
2465 			trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_ALL,
2466 					      "@sk_enqueue!");
2467 			__skb_queue_tail(xmitq, skb);
2468 		}
2469 		break;
2470 	}
2471 }
2472 
2473 /**
2474  * tipc_sk_rcv - handle a chain of incoming buffers
2475  * @net: the associated network namespace
2476  * @inputq: buffer list containing the buffers
2477  * Consumes all buffers in list until inputq is empty
2478  * Note: may be called in multiple threads referring to the same queue
2479  */
2480 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq)
2481 {
2482 	struct sk_buff_head xmitq;
2483 	u32 dnode, dport = 0;
2484 	int err;
2485 	struct tipc_sock *tsk;
2486 	struct sock *sk;
2487 	struct sk_buff *skb;
2488 
2489 	__skb_queue_head_init(&xmitq);
2490 	while (skb_queue_len(inputq)) {
2491 		dport = tipc_skb_peek_port(inputq, dport);
2492 		tsk = tipc_sk_lookup(net, dport);
2493 
2494 		if (likely(tsk)) {
2495 			sk = &tsk->sk;
2496 			if (likely(spin_trylock_bh(&sk->sk_lock.slock))) {
2497 				tipc_sk_enqueue(inputq, sk, dport, &xmitq);
2498 				spin_unlock_bh(&sk->sk_lock.slock);
2499 			}
2500 			/* Send pending response/rejected messages, if any */
2501 			tipc_node_distr_xmit(sock_net(sk), &xmitq);
2502 			sock_put(sk);
2503 			continue;
2504 		}
2505 		/* No destination socket => dequeue skb if still there */
2506 		skb = tipc_skb_dequeue(inputq, dport);
2507 		if (!skb)
2508 			return;
2509 
2510 		/* Try secondary lookup if unresolved named message */
2511 		err = TIPC_ERR_NO_PORT;
2512 		if (tipc_msg_lookup_dest(net, skb, &err))
2513 			goto xmit;
2514 
2515 		/* Prepare for message rejection */
2516 		if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err))
2517 			continue;
2518 
2519 		trace_tipc_sk_rej_msg(NULL, skb, TIPC_DUMP_NONE, "@sk_rcv!");
2520 xmit:
2521 		dnode = msg_destnode(buf_msg(skb));
2522 		tipc_node_xmit_skb(net, skb, dnode, dport);
2523 	}
2524 }
2525 
2526 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
2527 {
2528 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2529 	struct sock *sk = sock->sk;
2530 	int done;
2531 
2532 	do {
2533 		int err = sock_error(sk);
2534 		if (err)
2535 			return err;
2536 		if (!*timeo_p)
2537 			return -ETIMEDOUT;
2538 		if (signal_pending(current))
2539 			return sock_intr_errno(*timeo_p);
2540 		if (sk->sk_state == TIPC_DISCONNECTING)
2541 			break;
2542 
2543 		add_wait_queue(sk_sleep(sk), &wait);
2544 		done = sk_wait_event(sk, timeo_p, tipc_sk_connected(sk),
2545 				     &wait);
2546 		remove_wait_queue(sk_sleep(sk), &wait);
2547 	} while (!done);
2548 	return 0;
2549 }
2550 
2551 static bool tipc_sockaddr_is_sane(struct sockaddr_tipc *addr)
2552 {
2553 	if (addr->family != AF_TIPC)
2554 		return false;
2555 	if (addr->addrtype == TIPC_SERVICE_RANGE)
2556 		return (addr->addr.nameseq.lower <= addr->addr.nameseq.upper);
2557 	return (addr->addrtype == TIPC_SERVICE_ADDR ||
2558 		addr->addrtype == TIPC_SOCKET_ADDR);
2559 }
2560 
2561 /**
2562  * tipc_connect - establish a connection to another TIPC port
2563  * @sock: socket structure
2564  * @dest: socket address for destination port
2565  * @destlen: size of socket address data structure
2566  * @flags: file-related flags associated with socket
2567  *
2568  * Return: 0 on success, errno otherwise
2569  */
2570 static int tipc_connect(struct socket *sock, struct sockaddr *dest,
2571 			int destlen, int flags)
2572 {
2573 	struct sock *sk = sock->sk;
2574 	struct tipc_sock *tsk = tipc_sk(sk);
2575 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
2576 	struct msghdr m = {NULL,};
2577 	long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout;
2578 	int previous;
2579 	int res = 0;
2580 
2581 	if (destlen != sizeof(struct sockaddr_tipc))
2582 		return -EINVAL;
2583 
2584 	lock_sock(sk);
2585 
2586 	if (tsk->group) {
2587 		res = -EINVAL;
2588 		goto exit;
2589 	}
2590 
2591 	if (dst->family == AF_UNSPEC) {
2592 		memset(&tsk->peer, 0, sizeof(struct sockaddr_tipc));
2593 		if (!tipc_sk_type_connectionless(sk))
2594 			res = -EINVAL;
2595 		goto exit;
2596 	}
2597 	if (!tipc_sockaddr_is_sane(dst)) {
2598 		res = -EINVAL;
2599 		goto exit;
2600 	}
2601 	/* DGRAM/RDM connect(), just save the destaddr */
2602 	if (tipc_sk_type_connectionless(sk)) {
2603 		memcpy(&tsk->peer, dest, destlen);
2604 		goto exit;
2605 	} else if (dst->addrtype == TIPC_SERVICE_RANGE) {
2606 		res = -EINVAL;
2607 		goto exit;
2608 	}
2609 
2610 	previous = sk->sk_state;
2611 
2612 	switch (sk->sk_state) {
2613 	case TIPC_OPEN:
2614 		/* Send a 'SYN-' to destination */
2615 		m.msg_name = dest;
2616 		m.msg_namelen = destlen;
2617 
2618 		/* If connect is in non-blocking case, set MSG_DONTWAIT to
2619 		 * indicate send_msg() is never blocked.
2620 		 */
2621 		if (!timeout)
2622 			m.msg_flags = MSG_DONTWAIT;
2623 
2624 		res = __tipc_sendmsg(sock, &m, 0);
2625 		if ((res < 0) && (res != -EWOULDBLOCK))
2626 			goto exit;
2627 
2628 		/* Just entered TIPC_CONNECTING state; the only
2629 		 * difference is that return value in non-blocking
2630 		 * case is EINPROGRESS, rather than EALREADY.
2631 		 */
2632 		res = -EINPROGRESS;
2633 		fallthrough;
2634 	case TIPC_CONNECTING:
2635 		if (!timeout) {
2636 			if (previous == TIPC_CONNECTING)
2637 				res = -EALREADY;
2638 			goto exit;
2639 		}
2640 		timeout = msecs_to_jiffies(timeout);
2641 		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
2642 		res = tipc_wait_for_connect(sock, &timeout);
2643 		break;
2644 	case TIPC_ESTABLISHED:
2645 		res = -EISCONN;
2646 		break;
2647 	default:
2648 		res = -EINVAL;
2649 	}
2650 
2651 exit:
2652 	release_sock(sk);
2653 	return res;
2654 }
2655 
2656 /**
2657  * tipc_listen - allow socket to listen for incoming connections
2658  * @sock: socket structure
2659  * @len: (unused)
2660  *
2661  * Return: 0 on success, errno otherwise
2662  */
2663 static int tipc_listen(struct socket *sock, int len)
2664 {
2665 	struct sock *sk = sock->sk;
2666 	int res;
2667 
2668 	lock_sock(sk);
2669 	res = tipc_set_sk_state(sk, TIPC_LISTEN);
2670 	release_sock(sk);
2671 
2672 	return res;
2673 }
2674 
2675 static int tipc_wait_for_accept(struct socket *sock, long timeo)
2676 {
2677 	struct sock *sk = sock->sk;
2678 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2679 	int err;
2680 
2681 	/* True wake-one mechanism for incoming connections: only
2682 	 * one process gets woken up, not the 'whole herd'.
2683 	 * Since we do not 'race & poll' for established sockets
2684 	 * anymore, the common case will execute the loop only once.
2685 	*/
2686 	for (;;) {
2687 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
2688 			add_wait_queue(sk_sleep(sk), &wait);
2689 			release_sock(sk);
2690 			timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
2691 			lock_sock(sk);
2692 			remove_wait_queue(sk_sleep(sk), &wait);
2693 		}
2694 		err = 0;
2695 		if (!skb_queue_empty(&sk->sk_receive_queue))
2696 			break;
2697 		err = -EAGAIN;
2698 		if (!timeo)
2699 			break;
2700 		err = sock_intr_errno(timeo);
2701 		if (signal_pending(current))
2702 			break;
2703 	}
2704 	return err;
2705 }
2706 
2707 /**
2708  * tipc_accept - wait for connection request
2709  * @sock: listening socket
2710  * @new_sock: new socket that is to be connected
2711  * @flags: file-related flags associated with socket
2712  * @kern: caused by kernel or by userspace?
2713  *
2714  * Return: 0 on success, errno otherwise
2715  */
2716 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
2717 		       bool kern)
2718 {
2719 	struct sock *new_sk, *sk = sock->sk;
2720 	struct tipc_sock *new_tsock;
2721 	struct msghdr m = {NULL,};
2722 	struct tipc_msg *msg;
2723 	struct sk_buff *buf;
2724 	long timeo;
2725 	int res;
2726 
2727 	lock_sock(sk);
2728 
2729 	if (sk->sk_state != TIPC_LISTEN) {
2730 		res = -EINVAL;
2731 		goto exit;
2732 	}
2733 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2734 	res = tipc_wait_for_accept(sock, timeo);
2735 	if (res)
2736 		goto exit;
2737 
2738 	buf = skb_peek(&sk->sk_receive_queue);
2739 
2740 	res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, kern);
2741 	if (res)
2742 		goto exit;
2743 	security_sk_clone(sock->sk, new_sock->sk);
2744 
2745 	new_sk = new_sock->sk;
2746 	new_tsock = tipc_sk(new_sk);
2747 	msg = buf_msg(buf);
2748 
2749 	/* we lock on new_sk; but lockdep sees the lock on sk */
2750 	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
2751 
2752 	/*
2753 	 * Reject any stray messages received by new socket
2754 	 * before the socket lock was taken (very, very unlikely)
2755 	 */
2756 	tsk_rej_rx_queue(new_sk, TIPC_ERR_NO_PORT);
2757 
2758 	/* Connect new socket to it's peer */
2759 	tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg));
2760 
2761 	tsk_set_importance(new_sk, msg_importance(msg));
2762 	if (msg_named(msg)) {
2763 		new_tsock->conn_addrtype = TIPC_SERVICE_ADDR;
2764 		msg_set_nametype(&new_tsock->phdr, msg_nametype(msg));
2765 		msg_set_nameinst(&new_tsock->phdr, msg_nameinst(msg));
2766 	}
2767 
2768 	/*
2769 	 * Respond to 'SYN-' by discarding it & returning 'ACK'.
2770 	 * Respond to 'SYN+' by queuing it on new socket & returning 'ACK'.
2771 	 */
2772 	if (!msg_data_sz(msg)) {
2773 		tsk_advance_rx_queue(sk);
2774 	} else {
2775 		__skb_dequeue(&sk->sk_receive_queue);
2776 		__skb_queue_head(&new_sk->sk_receive_queue, buf);
2777 		skb_set_owner_r(buf, new_sk);
2778 	}
2779 	__tipc_sendstream(new_sock, &m, 0);
2780 	release_sock(new_sk);
2781 exit:
2782 	release_sock(sk);
2783 	return res;
2784 }
2785 
2786 /**
2787  * tipc_shutdown - shutdown socket connection
2788  * @sock: socket structure
2789  * @how: direction to close (must be SHUT_RDWR)
2790  *
2791  * Terminates connection (if necessary), then purges socket's receive queue.
2792  *
2793  * Return: 0 on success, errno otherwise
2794  */
2795 static int tipc_shutdown(struct socket *sock, int how)
2796 {
2797 	struct sock *sk = sock->sk;
2798 	int res;
2799 
2800 	if (how != SHUT_RDWR)
2801 		return -EINVAL;
2802 
2803 	lock_sock(sk);
2804 
2805 	trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " ");
2806 	__tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
2807 	sk->sk_shutdown = SHUTDOWN_MASK;
2808 
2809 	if (sk->sk_state == TIPC_DISCONNECTING) {
2810 		/* Discard any unreceived messages */
2811 		__skb_queue_purge(&sk->sk_receive_queue);
2812 
2813 		res = 0;
2814 	} else {
2815 		res = -ENOTCONN;
2816 	}
2817 	/* Wake up anyone sleeping in poll. */
2818 	sk->sk_state_change(sk);
2819 
2820 	release_sock(sk);
2821 	return res;
2822 }
2823 
2824 static void tipc_sk_check_probing_state(struct sock *sk,
2825 					struct sk_buff_head *list)
2826 {
2827 	struct tipc_sock *tsk = tipc_sk(sk);
2828 	u32 pnode = tsk_peer_node(tsk);
2829 	u32 pport = tsk_peer_port(tsk);
2830 	u32 self = tsk_own_node(tsk);
2831 	u32 oport = tsk->portid;
2832 	struct sk_buff *skb;
2833 
2834 	if (tsk->probe_unacked) {
2835 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2836 		sk->sk_err = ECONNABORTED;
2837 		tipc_node_remove_conn(sock_net(sk), pnode, pport);
2838 		sk->sk_state_change(sk);
2839 		return;
2840 	}
2841 	/* Prepare new probe */
2842 	skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE, INT_H_SIZE, 0,
2843 			      pnode, self, pport, oport, TIPC_OK);
2844 	if (skb)
2845 		__skb_queue_tail(list, skb);
2846 	tsk->probe_unacked = true;
2847 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
2848 }
2849 
2850 static void tipc_sk_retry_connect(struct sock *sk, struct sk_buff_head *list)
2851 {
2852 	struct tipc_sock *tsk = tipc_sk(sk);
2853 
2854 	/* Try again later if dest link is congested */
2855 	if (tsk->cong_link_cnt) {
2856 		sk_reset_timer(sk, &sk->sk_timer,
2857 			       jiffies + msecs_to_jiffies(100));
2858 		return;
2859 	}
2860 	/* Prepare SYN for retransmit */
2861 	tipc_msg_skb_clone(&sk->sk_write_queue, list);
2862 }
2863 
2864 static void tipc_sk_timeout(struct timer_list *t)
2865 {
2866 	struct sock *sk = from_timer(sk, t, sk_timer);
2867 	struct tipc_sock *tsk = tipc_sk(sk);
2868 	u32 pnode = tsk_peer_node(tsk);
2869 	struct sk_buff_head list;
2870 	int rc = 0;
2871 
2872 	__skb_queue_head_init(&list);
2873 	bh_lock_sock(sk);
2874 
2875 	/* Try again later if socket is busy */
2876 	if (sock_owned_by_user(sk)) {
2877 		sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 20);
2878 		bh_unlock_sock(sk);
2879 		sock_put(sk);
2880 		return;
2881 	}
2882 
2883 	if (sk->sk_state == TIPC_ESTABLISHED)
2884 		tipc_sk_check_probing_state(sk, &list);
2885 	else if (sk->sk_state == TIPC_CONNECTING)
2886 		tipc_sk_retry_connect(sk, &list);
2887 
2888 	bh_unlock_sock(sk);
2889 
2890 	if (!skb_queue_empty(&list))
2891 		rc = tipc_node_xmit(sock_net(sk), &list, pnode, tsk->portid);
2892 
2893 	/* SYN messages may cause link congestion */
2894 	if (rc == -ELINKCONG) {
2895 		tipc_dest_push(&tsk->cong_links, pnode, 0);
2896 		tsk->cong_link_cnt = 1;
2897 	}
2898 	sock_put(sk);
2899 }
2900 
2901 static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2902 {
2903 	struct sock *sk = &tsk->sk;
2904 	struct net *net = sock_net(sk);
2905 	struct tipc_socket_addr skaddr;
2906 	struct publication *p;
2907 	u32 key;
2908 
2909 	if (tipc_sk_connected(sk))
2910 		return -EINVAL;
2911 	key = tsk->portid + tsk->pub_count + 1;
2912 	if (key == tsk->portid)
2913 		return -EADDRINUSE;
2914 	skaddr.ref = tsk->portid;
2915 	skaddr.node = tipc_own_addr(net);
2916 	p = tipc_nametbl_publish(net, ua, &skaddr, key);
2917 	if (unlikely(!p))
2918 		return -EINVAL;
2919 
2920 	list_add(&p->binding_sock, &tsk->publications);
2921 	tsk->pub_count++;
2922 	tsk->published = true;
2923 	return 0;
2924 }
2925 
2926 static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua)
2927 {
2928 	struct net *net = sock_net(&tsk->sk);
2929 	struct publication *safe, *p;
2930 	struct tipc_uaddr _ua;
2931 	int rc = -EINVAL;
2932 
2933 	list_for_each_entry_safe(p, safe, &tsk->publications, binding_sock) {
2934 		if (!ua) {
2935 			tipc_uaddr(&_ua, TIPC_SERVICE_RANGE, p->scope,
2936 				   p->sr.type, p->sr.lower, p->sr.upper);
2937 			tipc_nametbl_withdraw(net, &_ua, &p->sk, p->key);
2938 			continue;
2939 		}
2940 		/* Unbind specific publication */
2941 		if (p->scope != ua->scope)
2942 			continue;
2943 		if (p->sr.type != ua->sr.type)
2944 			continue;
2945 		if (p->sr.lower != ua->sr.lower)
2946 			continue;
2947 		if (p->sr.upper != ua->sr.upper)
2948 			break;
2949 		tipc_nametbl_withdraw(net, ua, &p->sk, p->key);
2950 		rc = 0;
2951 		break;
2952 	}
2953 	if (list_empty(&tsk->publications)) {
2954 		tsk->published = 0;
2955 		rc = 0;
2956 	}
2957 	return rc;
2958 }
2959 
2960 /* tipc_sk_reinit: set non-zero address in all existing sockets
2961  *                 when we go from standalone to network mode.
2962  */
2963 void tipc_sk_reinit(struct net *net)
2964 {
2965 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2966 	struct rhashtable_iter iter;
2967 	struct tipc_sock *tsk;
2968 	struct tipc_msg *msg;
2969 
2970 	rhashtable_walk_enter(&tn->sk_rht, &iter);
2971 
2972 	do {
2973 		rhashtable_walk_start(&iter);
2974 
2975 		while ((tsk = rhashtable_walk_next(&iter)) && !IS_ERR(tsk)) {
2976 			sock_hold(&tsk->sk);
2977 			rhashtable_walk_stop(&iter);
2978 			lock_sock(&tsk->sk);
2979 			msg = &tsk->phdr;
2980 			msg_set_prevnode(msg, tipc_own_addr(net));
2981 			msg_set_orignode(msg, tipc_own_addr(net));
2982 			release_sock(&tsk->sk);
2983 			rhashtable_walk_start(&iter);
2984 			sock_put(&tsk->sk);
2985 		}
2986 
2987 		rhashtable_walk_stop(&iter);
2988 	} while (tsk == ERR_PTR(-EAGAIN));
2989 
2990 	rhashtable_walk_exit(&iter);
2991 }
2992 
2993 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)
2994 {
2995 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2996 	struct tipc_sock *tsk;
2997 
2998 	rcu_read_lock();
2999 	tsk = rhashtable_lookup(&tn->sk_rht, &portid, tsk_rht_params);
3000 	if (tsk)
3001 		sock_hold(&tsk->sk);
3002 	rcu_read_unlock();
3003 
3004 	return tsk;
3005 }
3006 
3007 static int tipc_sk_insert(struct tipc_sock *tsk)
3008 {
3009 	struct sock *sk = &tsk->sk;
3010 	struct net *net = sock_net(sk);
3011 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3012 	u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1;
3013 	u32 portid = prandom_u32() % remaining + TIPC_MIN_PORT;
3014 
3015 	while (remaining--) {
3016 		portid++;
3017 		if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT))
3018 			portid = TIPC_MIN_PORT;
3019 		tsk->portid = portid;
3020 		sock_hold(&tsk->sk);
3021 		if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node,
3022 						   tsk_rht_params))
3023 			return 0;
3024 		sock_put(&tsk->sk);
3025 	}
3026 
3027 	return -1;
3028 }
3029 
3030 static void tipc_sk_remove(struct tipc_sock *tsk)
3031 {
3032 	struct sock *sk = &tsk->sk;
3033 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
3034 
3035 	if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) {
3036 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
3037 		__sock_put(sk);
3038 	}
3039 }
3040 
3041 static const struct rhashtable_params tsk_rht_params = {
3042 	.nelem_hint = 192,
3043 	.head_offset = offsetof(struct tipc_sock, node),
3044 	.key_offset = offsetof(struct tipc_sock, portid),
3045 	.key_len = sizeof(u32), /* portid */
3046 	.max_size = 1048576,
3047 	.min_size = 256,
3048 	.automatic_shrinking = true,
3049 };
3050 
3051 int tipc_sk_rht_init(struct net *net)
3052 {
3053 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3054 
3055 	return rhashtable_init(&tn->sk_rht, &tsk_rht_params);
3056 }
3057 
3058 void tipc_sk_rht_destroy(struct net *net)
3059 {
3060 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3061 
3062 	/* Wait for socket readers to complete */
3063 	synchronize_net();
3064 
3065 	rhashtable_destroy(&tn->sk_rht);
3066 }
3067 
3068 static int tipc_sk_join(struct tipc_sock *tsk, struct tipc_group_req *mreq)
3069 {
3070 	struct net *net = sock_net(&tsk->sk);
3071 	struct tipc_group *grp = tsk->group;
3072 	struct tipc_msg *hdr = &tsk->phdr;
3073 	struct tipc_uaddr ua;
3074 	int rc;
3075 
3076 	if (mreq->type < TIPC_RESERVED_TYPES)
3077 		return -EACCES;
3078 	if (mreq->scope > TIPC_NODE_SCOPE)
3079 		return -EINVAL;
3080 	if (mreq->scope != TIPC_NODE_SCOPE)
3081 		mreq->scope = TIPC_CLUSTER_SCOPE;
3082 	if (grp)
3083 		return -EACCES;
3084 	grp = tipc_group_create(net, tsk->portid, mreq, &tsk->group_is_open);
3085 	if (!grp)
3086 		return -ENOMEM;
3087 	tsk->group = grp;
3088 	msg_set_lookup_scope(hdr, mreq->scope);
3089 	msg_set_nametype(hdr, mreq->type);
3090 	msg_set_dest_droppable(hdr, true);
3091 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, mreq->scope,
3092 		   mreq->type, mreq->instance, mreq->instance);
3093 	tipc_nametbl_build_group(net, grp, &ua);
3094 	rc = tipc_sk_publish(tsk, &ua);
3095 	if (rc) {
3096 		tipc_group_delete(net, grp);
3097 		tsk->group = NULL;
3098 		return rc;
3099 	}
3100 	/* Eliminate any risk that a broadcast overtakes sent JOINs */
3101 	tsk->mc_method.rcast = true;
3102 	tsk->mc_method.mandatory = true;
3103 	tipc_group_join(net, grp, &tsk->sk.sk_rcvbuf);
3104 	return rc;
3105 }
3106 
3107 static int tipc_sk_leave(struct tipc_sock *tsk)
3108 {
3109 	struct net *net = sock_net(&tsk->sk);
3110 	struct tipc_group *grp = tsk->group;
3111 	struct tipc_uaddr ua;
3112 	int scope;
3113 
3114 	if (!grp)
3115 		return -EINVAL;
3116 	ua.addrtype = TIPC_SERVICE_RANGE;
3117 	tipc_group_self(grp, &ua.sr, &scope);
3118 	ua.scope = scope;
3119 	tipc_group_delete(net, grp);
3120 	tsk->group = NULL;
3121 	tipc_sk_withdraw(tsk, &ua);
3122 	return 0;
3123 }
3124 
3125 /**
3126  * tipc_setsockopt - set socket option
3127  * @sock: socket structure
3128  * @lvl: option level
3129  * @opt: option identifier
3130  * @ov: pointer to new option value
3131  * @ol: length of option value
3132  *
3133  * For stream sockets only, accepts and ignores all IPPROTO_TCP options
3134  * (to ease compatibility).
3135  *
3136  * Return: 0 on success, errno otherwise
3137  */
3138 static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
3139 			   sockptr_t ov, unsigned int ol)
3140 {
3141 	struct sock *sk = sock->sk;
3142 	struct tipc_sock *tsk = tipc_sk(sk);
3143 	struct tipc_group_req mreq;
3144 	u32 value = 0;
3145 	int res = 0;
3146 
3147 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
3148 		return 0;
3149 	if (lvl != SOL_TIPC)
3150 		return -ENOPROTOOPT;
3151 
3152 	switch (opt) {
3153 	case TIPC_IMPORTANCE:
3154 	case TIPC_SRC_DROPPABLE:
3155 	case TIPC_DEST_DROPPABLE:
3156 	case TIPC_CONN_TIMEOUT:
3157 	case TIPC_NODELAY:
3158 		if (ol < sizeof(value))
3159 			return -EINVAL;
3160 		if (copy_from_sockptr(&value, ov, sizeof(u32)))
3161 			return -EFAULT;
3162 		break;
3163 	case TIPC_GROUP_JOIN:
3164 		if (ol < sizeof(mreq))
3165 			return -EINVAL;
3166 		if (copy_from_sockptr(&mreq, ov, sizeof(mreq)))
3167 			return -EFAULT;
3168 		break;
3169 	default:
3170 		if (!sockptr_is_null(ov) || ol)
3171 			return -EINVAL;
3172 	}
3173 
3174 	lock_sock(sk);
3175 
3176 	switch (opt) {
3177 	case TIPC_IMPORTANCE:
3178 		res = tsk_set_importance(sk, value);
3179 		break;
3180 	case TIPC_SRC_DROPPABLE:
3181 		if (sock->type != SOCK_STREAM)
3182 			tsk_set_unreliable(tsk, value);
3183 		else
3184 			res = -ENOPROTOOPT;
3185 		break;
3186 	case TIPC_DEST_DROPPABLE:
3187 		tsk_set_unreturnable(tsk, value);
3188 		break;
3189 	case TIPC_CONN_TIMEOUT:
3190 		tipc_sk(sk)->conn_timeout = value;
3191 		break;
3192 	case TIPC_MCAST_BROADCAST:
3193 		tsk->mc_method.rcast = false;
3194 		tsk->mc_method.mandatory = true;
3195 		break;
3196 	case TIPC_MCAST_REPLICAST:
3197 		tsk->mc_method.rcast = true;
3198 		tsk->mc_method.mandatory = true;
3199 		break;
3200 	case TIPC_GROUP_JOIN:
3201 		res = tipc_sk_join(tsk, &mreq);
3202 		break;
3203 	case TIPC_GROUP_LEAVE:
3204 		res = tipc_sk_leave(tsk);
3205 		break;
3206 	case TIPC_NODELAY:
3207 		tsk->nodelay = !!value;
3208 		tsk_set_nagle(tsk);
3209 		break;
3210 	default:
3211 		res = -EINVAL;
3212 	}
3213 
3214 	release_sock(sk);
3215 
3216 	return res;
3217 }
3218 
3219 /**
3220  * tipc_getsockopt - get socket option
3221  * @sock: socket structure
3222  * @lvl: option level
3223  * @opt: option identifier
3224  * @ov: receptacle for option value
3225  * @ol: receptacle for length of option value
3226  *
3227  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
3228  * (to ease compatibility).
3229  *
3230  * Return: 0 on success, errno otherwise
3231  */
3232 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
3233 			   char __user *ov, int __user *ol)
3234 {
3235 	struct sock *sk = sock->sk;
3236 	struct tipc_sock *tsk = tipc_sk(sk);
3237 	struct tipc_service_range seq;
3238 	int len, scope;
3239 	u32 value;
3240 	int res;
3241 
3242 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
3243 		return put_user(0, ol);
3244 	if (lvl != SOL_TIPC)
3245 		return -ENOPROTOOPT;
3246 	res = get_user(len, ol);
3247 	if (res)
3248 		return res;
3249 
3250 	lock_sock(sk);
3251 
3252 	switch (opt) {
3253 	case TIPC_IMPORTANCE:
3254 		value = tsk_importance(tsk);
3255 		break;
3256 	case TIPC_SRC_DROPPABLE:
3257 		value = tsk_unreliable(tsk);
3258 		break;
3259 	case TIPC_DEST_DROPPABLE:
3260 		value = tsk_unreturnable(tsk);
3261 		break;
3262 	case TIPC_CONN_TIMEOUT:
3263 		value = tsk->conn_timeout;
3264 		/* no need to set "res", since already 0 at this point */
3265 		break;
3266 	case TIPC_NODE_RECVQ_DEPTH:
3267 		value = 0; /* was tipc_queue_size, now obsolete */
3268 		break;
3269 	case TIPC_SOCK_RECVQ_DEPTH:
3270 		value = skb_queue_len(&sk->sk_receive_queue);
3271 		break;
3272 	case TIPC_SOCK_RECVQ_USED:
3273 		value = sk_rmem_alloc_get(sk);
3274 		break;
3275 	case TIPC_GROUP_JOIN:
3276 		seq.type = 0;
3277 		if (tsk->group)
3278 			tipc_group_self(tsk->group, &seq, &scope);
3279 		value = seq.type;
3280 		break;
3281 	default:
3282 		res = -EINVAL;
3283 	}
3284 
3285 	release_sock(sk);
3286 
3287 	if (res)
3288 		return res;	/* "get" failed */
3289 
3290 	if (len < sizeof(value))
3291 		return -EINVAL;
3292 
3293 	if (copy_to_user(ov, &value, sizeof(value)))
3294 		return -EFAULT;
3295 
3296 	return put_user(sizeof(value), ol);
3297 }
3298 
3299 static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3300 {
3301 	struct net *net = sock_net(sock->sk);
3302 	struct tipc_sioc_nodeid_req nr = {0};
3303 	struct tipc_sioc_ln_req lnr;
3304 	void __user *argp = (void __user *)arg;
3305 
3306 	switch (cmd) {
3307 	case SIOCGETLINKNAME:
3308 		if (copy_from_user(&lnr, argp, sizeof(lnr)))
3309 			return -EFAULT;
3310 		if (!tipc_node_get_linkname(net,
3311 					    lnr.bearer_id & 0xffff, lnr.peer,
3312 					    lnr.linkname, TIPC_MAX_LINK_NAME)) {
3313 			if (copy_to_user(argp, &lnr, sizeof(lnr)))
3314 				return -EFAULT;
3315 			return 0;
3316 		}
3317 		return -EADDRNOTAVAIL;
3318 	case SIOCGETNODEID:
3319 		if (copy_from_user(&nr, argp, sizeof(nr)))
3320 			return -EFAULT;
3321 		if (!tipc_node_get_id(net, nr.peer, nr.node_id))
3322 			return -EADDRNOTAVAIL;
3323 		if (copy_to_user(argp, &nr, sizeof(nr)))
3324 			return -EFAULT;
3325 		return 0;
3326 	default:
3327 		return -ENOIOCTLCMD;
3328 	}
3329 }
3330 
3331 static int tipc_socketpair(struct socket *sock1, struct socket *sock2)
3332 {
3333 	struct tipc_sock *tsk2 = tipc_sk(sock2->sk);
3334 	struct tipc_sock *tsk1 = tipc_sk(sock1->sk);
3335 	u32 onode = tipc_own_addr(sock_net(sock1->sk));
3336 
3337 	tsk1->peer.family = AF_TIPC;
3338 	tsk1->peer.addrtype = TIPC_SOCKET_ADDR;
3339 	tsk1->peer.scope = TIPC_NODE_SCOPE;
3340 	tsk1->peer.addr.id.ref = tsk2->portid;
3341 	tsk1->peer.addr.id.node = onode;
3342 	tsk2->peer.family = AF_TIPC;
3343 	tsk2->peer.addrtype = TIPC_SOCKET_ADDR;
3344 	tsk2->peer.scope = TIPC_NODE_SCOPE;
3345 	tsk2->peer.addr.id.ref = tsk1->portid;
3346 	tsk2->peer.addr.id.node = onode;
3347 
3348 	tipc_sk_finish_conn(tsk1, tsk2->portid, onode);
3349 	tipc_sk_finish_conn(tsk2, tsk1->portid, onode);
3350 	return 0;
3351 }
3352 
3353 /* Protocol switches for the various types of TIPC sockets */
3354 
3355 static const struct proto_ops msg_ops = {
3356 	.owner		= THIS_MODULE,
3357 	.family		= AF_TIPC,
3358 	.release	= tipc_release,
3359 	.bind		= tipc_bind,
3360 	.connect	= tipc_connect,
3361 	.socketpair	= tipc_socketpair,
3362 	.accept		= sock_no_accept,
3363 	.getname	= tipc_getname,
3364 	.poll		= tipc_poll,
3365 	.ioctl		= tipc_ioctl,
3366 	.listen		= sock_no_listen,
3367 	.shutdown	= tipc_shutdown,
3368 	.setsockopt	= tipc_setsockopt,
3369 	.getsockopt	= tipc_getsockopt,
3370 	.sendmsg	= tipc_sendmsg,
3371 	.recvmsg	= tipc_recvmsg,
3372 	.mmap		= sock_no_mmap,
3373 	.sendpage	= sock_no_sendpage
3374 };
3375 
3376 static const struct proto_ops packet_ops = {
3377 	.owner		= THIS_MODULE,
3378 	.family		= AF_TIPC,
3379 	.release	= tipc_release,
3380 	.bind		= tipc_bind,
3381 	.connect	= tipc_connect,
3382 	.socketpair	= tipc_socketpair,
3383 	.accept		= tipc_accept,
3384 	.getname	= tipc_getname,
3385 	.poll		= tipc_poll,
3386 	.ioctl		= tipc_ioctl,
3387 	.listen		= tipc_listen,
3388 	.shutdown	= tipc_shutdown,
3389 	.setsockopt	= tipc_setsockopt,
3390 	.getsockopt	= tipc_getsockopt,
3391 	.sendmsg	= tipc_send_packet,
3392 	.recvmsg	= tipc_recvmsg,
3393 	.mmap		= sock_no_mmap,
3394 	.sendpage	= sock_no_sendpage
3395 };
3396 
3397 static const struct proto_ops stream_ops = {
3398 	.owner		= THIS_MODULE,
3399 	.family		= AF_TIPC,
3400 	.release	= tipc_release,
3401 	.bind		= tipc_bind,
3402 	.connect	= tipc_connect,
3403 	.socketpair	= tipc_socketpair,
3404 	.accept		= tipc_accept,
3405 	.getname	= tipc_getname,
3406 	.poll		= tipc_poll,
3407 	.ioctl		= tipc_ioctl,
3408 	.listen		= tipc_listen,
3409 	.shutdown	= tipc_shutdown,
3410 	.setsockopt	= tipc_setsockopt,
3411 	.getsockopt	= tipc_getsockopt,
3412 	.sendmsg	= tipc_sendstream,
3413 	.recvmsg	= tipc_recvstream,
3414 	.mmap		= sock_no_mmap,
3415 	.sendpage	= sock_no_sendpage
3416 };
3417 
3418 static const struct net_proto_family tipc_family_ops = {
3419 	.owner		= THIS_MODULE,
3420 	.family		= AF_TIPC,
3421 	.create		= tipc_sk_create
3422 };
3423 
3424 static struct proto tipc_proto = {
3425 	.name		= "TIPC",
3426 	.owner		= THIS_MODULE,
3427 	.obj_size	= sizeof(struct tipc_sock),
3428 	.sysctl_rmem	= sysctl_tipc_rmem
3429 };
3430 
3431 /**
3432  * tipc_socket_init - initialize TIPC socket interface
3433  *
3434  * Return: 0 on success, errno otherwise
3435  */
3436 int tipc_socket_init(void)
3437 {
3438 	int res;
3439 
3440 	res = proto_register(&tipc_proto, 1);
3441 	if (res) {
3442 		pr_err("Failed to register TIPC protocol type\n");
3443 		goto out;
3444 	}
3445 
3446 	res = sock_register(&tipc_family_ops);
3447 	if (res) {
3448 		pr_err("Failed to register TIPC socket type\n");
3449 		proto_unregister(&tipc_proto);
3450 		goto out;
3451 	}
3452  out:
3453 	return res;
3454 }
3455 
3456 /**
3457  * tipc_socket_stop - stop TIPC socket interface
3458  */
3459 void tipc_socket_stop(void)
3460 {
3461 	sock_unregister(tipc_family_ops.family);
3462 	proto_unregister(&tipc_proto);
3463 }
3464 
3465 /* Caller should hold socket lock for the passed tipc socket. */
3466 static int __tipc_nl_add_sk_con(struct sk_buff *skb, struct tipc_sock *tsk)
3467 {
3468 	u32 peer_node, peer_port;
3469 	u32 conn_type, conn_instance;
3470 	struct nlattr *nest;
3471 
3472 	peer_node = tsk_peer_node(tsk);
3473 	peer_port = tsk_peer_port(tsk);
3474 	conn_type = msg_nametype(&tsk->phdr);
3475 	conn_instance = msg_nameinst(&tsk->phdr);
3476 	nest = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_CON);
3477 	if (!nest)
3478 		return -EMSGSIZE;
3479 
3480 	if (nla_put_u32(skb, TIPC_NLA_CON_NODE, peer_node))
3481 		goto msg_full;
3482 	if (nla_put_u32(skb, TIPC_NLA_CON_SOCK, peer_port))
3483 		goto msg_full;
3484 
3485 	if (tsk->conn_addrtype != 0) {
3486 		if (nla_put_flag(skb, TIPC_NLA_CON_FLAG))
3487 			goto msg_full;
3488 		if (nla_put_u32(skb, TIPC_NLA_CON_TYPE, conn_type))
3489 			goto msg_full;
3490 		if (nla_put_u32(skb, TIPC_NLA_CON_INST, conn_instance))
3491 			goto msg_full;
3492 	}
3493 	nla_nest_end(skb, nest);
3494 
3495 	return 0;
3496 
3497 msg_full:
3498 	nla_nest_cancel(skb, nest);
3499 
3500 	return -EMSGSIZE;
3501 }
3502 
3503 static int __tipc_nl_add_sk_info(struct sk_buff *skb, struct tipc_sock
3504 			  *tsk)
3505 {
3506 	struct net *net = sock_net(skb->sk);
3507 	struct sock *sk = &tsk->sk;
3508 
3509 	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid) ||
3510 	    nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tipc_own_addr(net)))
3511 		return -EMSGSIZE;
3512 
3513 	if (tipc_sk_connected(sk)) {
3514 		if (__tipc_nl_add_sk_con(skb, tsk))
3515 			return -EMSGSIZE;
3516 	} else if (!list_empty(&tsk->publications)) {
3517 		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
3518 			return -EMSGSIZE;
3519 	}
3520 	return 0;
3521 }
3522 
3523 /* Caller should hold socket lock for the passed tipc socket. */
3524 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
3525 			    struct tipc_sock *tsk)
3526 {
3527 	struct nlattr *attrs;
3528 	void *hdr;
3529 
3530 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3531 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
3532 	if (!hdr)
3533 		goto msg_cancel;
3534 
3535 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3536 	if (!attrs)
3537 		goto genlmsg_cancel;
3538 
3539 	if (__tipc_nl_add_sk_info(skb, tsk))
3540 		goto attr_msg_cancel;
3541 
3542 	nla_nest_end(skb, attrs);
3543 	genlmsg_end(skb, hdr);
3544 
3545 	return 0;
3546 
3547 attr_msg_cancel:
3548 	nla_nest_cancel(skb, attrs);
3549 genlmsg_cancel:
3550 	genlmsg_cancel(skb, hdr);
3551 msg_cancel:
3552 	return -EMSGSIZE;
3553 }
3554 
3555 int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
3556 		    int (*skb_handler)(struct sk_buff *skb,
3557 				       struct netlink_callback *cb,
3558 				       struct tipc_sock *tsk))
3559 {
3560 	struct rhashtable_iter *iter = (void *)cb->args[4];
3561 	struct tipc_sock *tsk;
3562 	int err;
3563 
3564 	rhashtable_walk_start(iter);
3565 	while ((tsk = rhashtable_walk_next(iter)) != NULL) {
3566 		if (IS_ERR(tsk)) {
3567 			err = PTR_ERR(tsk);
3568 			if (err == -EAGAIN) {
3569 				err = 0;
3570 				continue;
3571 			}
3572 			break;
3573 		}
3574 
3575 		sock_hold(&tsk->sk);
3576 		rhashtable_walk_stop(iter);
3577 		lock_sock(&tsk->sk);
3578 		err = skb_handler(skb, cb, tsk);
3579 		if (err) {
3580 			release_sock(&tsk->sk);
3581 			sock_put(&tsk->sk);
3582 			goto out;
3583 		}
3584 		release_sock(&tsk->sk);
3585 		rhashtable_walk_start(iter);
3586 		sock_put(&tsk->sk);
3587 	}
3588 	rhashtable_walk_stop(iter);
3589 out:
3590 	return skb->len;
3591 }
3592 EXPORT_SYMBOL(tipc_nl_sk_walk);
3593 
3594 int tipc_dump_start(struct netlink_callback *cb)
3595 {
3596 	return __tipc_dump_start(cb, sock_net(cb->skb->sk));
3597 }
3598 EXPORT_SYMBOL(tipc_dump_start);
3599 
3600 int __tipc_dump_start(struct netlink_callback *cb, struct net *net)
3601 {
3602 	/* tipc_nl_name_table_dump() uses cb->args[0...3]. */
3603 	struct rhashtable_iter *iter = (void *)cb->args[4];
3604 	struct tipc_net *tn = tipc_net(net);
3605 
3606 	if (!iter) {
3607 		iter = kmalloc(sizeof(*iter), GFP_KERNEL);
3608 		if (!iter)
3609 			return -ENOMEM;
3610 
3611 		cb->args[4] = (long)iter;
3612 	}
3613 
3614 	rhashtable_walk_enter(&tn->sk_rht, iter);
3615 	return 0;
3616 }
3617 
3618 int tipc_dump_done(struct netlink_callback *cb)
3619 {
3620 	struct rhashtable_iter *hti = (void *)cb->args[4];
3621 
3622 	rhashtable_walk_exit(hti);
3623 	kfree(hti);
3624 	return 0;
3625 }
3626 EXPORT_SYMBOL(tipc_dump_done);
3627 
3628 int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct netlink_callback *cb,
3629 			   struct tipc_sock *tsk, u32 sk_filter_state,
3630 			   u64 (*tipc_diag_gen_cookie)(struct sock *sk))
3631 {
3632 	struct sock *sk = &tsk->sk;
3633 	struct nlattr *attrs;
3634 	struct nlattr *stat;
3635 
3636 	/*filter response w.r.t sk_state*/
3637 	if (!(sk_filter_state & (1 << sk->sk_state)))
3638 		return 0;
3639 
3640 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK);
3641 	if (!attrs)
3642 		goto msg_cancel;
3643 
3644 	if (__tipc_nl_add_sk_info(skb, tsk))
3645 		goto attr_msg_cancel;
3646 
3647 	if (nla_put_u32(skb, TIPC_NLA_SOCK_TYPE, (u32)sk->sk_type) ||
3648 	    nla_put_u32(skb, TIPC_NLA_SOCK_TIPC_STATE, (u32)sk->sk_state) ||
3649 	    nla_put_u32(skb, TIPC_NLA_SOCK_INO, sock_i_ino(sk)) ||
3650 	    nla_put_u32(skb, TIPC_NLA_SOCK_UID,
3651 			from_kuid_munged(sk_user_ns(NETLINK_CB(cb->skb).sk),
3652 					 sock_i_uid(sk))) ||
3653 	    nla_put_u64_64bit(skb, TIPC_NLA_SOCK_COOKIE,
3654 			      tipc_diag_gen_cookie(sk),
3655 			      TIPC_NLA_SOCK_PAD))
3656 		goto attr_msg_cancel;
3657 
3658 	stat = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_STAT);
3659 	if (!stat)
3660 		goto attr_msg_cancel;
3661 
3662 	if (nla_put_u32(skb, TIPC_NLA_SOCK_STAT_RCVQ,
3663 			skb_queue_len(&sk->sk_receive_queue)) ||
3664 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_SENDQ,
3665 			skb_queue_len(&sk->sk_write_queue)) ||
3666 	    nla_put_u32(skb, TIPC_NLA_SOCK_STAT_DROP,
3667 			atomic_read(&sk->sk_drops)))
3668 		goto stat_msg_cancel;
3669 
3670 	if (tsk->cong_link_cnt &&
3671 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_LINK_CONG))
3672 		goto stat_msg_cancel;
3673 
3674 	if (tsk_conn_cong(tsk) &&
3675 	    nla_put_flag(skb, TIPC_NLA_SOCK_STAT_CONN_CONG))
3676 		goto stat_msg_cancel;
3677 
3678 	nla_nest_end(skb, stat);
3679 
3680 	if (tsk->group)
3681 		if (tipc_group_fill_sock_diag(tsk->group, skb))
3682 			goto stat_msg_cancel;
3683 
3684 	nla_nest_end(skb, attrs);
3685 
3686 	return 0;
3687 
3688 stat_msg_cancel:
3689 	nla_nest_cancel(skb, stat);
3690 attr_msg_cancel:
3691 	nla_nest_cancel(skb, attrs);
3692 msg_cancel:
3693 	return -EMSGSIZE;
3694 }
3695 EXPORT_SYMBOL(tipc_sk_fill_sock_diag);
3696 
3697 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
3698 {
3699 	return tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk);
3700 }
3701 
3702 /* Caller should hold socket lock for the passed tipc socket. */
3703 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
3704 				 struct netlink_callback *cb,
3705 				 struct publication *publ)
3706 {
3707 	void *hdr;
3708 	struct nlattr *attrs;
3709 
3710 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3711 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET);
3712 	if (!hdr)
3713 		goto msg_cancel;
3714 
3715 	attrs = nla_nest_start_noflag(skb, TIPC_NLA_PUBL);
3716 	if (!attrs)
3717 		goto genlmsg_cancel;
3718 
3719 	if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key))
3720 		goto attr_msg_cancel;
3721 	if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->sr.type))
3722 		goto attr_msg_cancel;
3723 	if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->sr.lower))
3724 		goto attr_msg_cancel;
3725 	if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->sr.upper))
3726 		goto attr_msg_cancel;
3727 
3728 	nla_nest_end(skb, attrs);
3729 	genlmsg_end(skb, hdr);
3730 
3731 	return 0;
3732 
3733 attr_msg_cancel:
3734 	nla_nest_cancel(skb, attrs);
3735 genlmsg_cancel:
3736 	genlmsg_cancel(skb, hdr);
3737 msg_cancel:
3738 	return -EMSGSIZE;
3739 }
3740 
3741 /* Caller should hold socket lock for the passed tipc socket. */
3742 static int __tipc_nl_list_sk_publ(struct sk_buff *skb,
3743 				  struct netlink_callback *cb,
3744 				  struct tipc_sock *tsk, u32 *last_publ)
3745 {
3746 	int err;
3747 	struct publication *p;
3748 
3749 	if (*last_publ) {
3750 		list_for_each_entry(p, &tsk->publications, binding_sock) {
3751 			if (p->key == *last_publ)
3752 				break;
3753 		}
3754 		if (list_entry_is_head(p, &tsk->publications, binding_sock)) {
3755 			/* We never set seq or call nl_dump_check_consistent()
3756 			 * this means that setting prev_seq here will cause the
3757 			 * consistence check to fail in the netlink callback
3758 			 * handler. Resulting in the last NLMSG_DONE message
3759 			 * having the NLM_F_DUMP_INTR flag set.
3760 			 */
3761 			cb->prev_seq = 1;
3762 			*last_publ = 0;
3763 			return -EPIPE;
3764 		}
3765 	} else {
3766 		p = list_first_entry(&tsk->publications, struct publication,
3767 				     binding_sock);
3768 	}
3769 
3770 	list_for_each_entry_from(p, &tsk->publications, binding_sock) {
3771 		err = __tipc_nl_add_sk_publ(skb, cb, p);
3772 		if (err) {
3773 			*last_publ = p->key;
3774 			return err;
3775 		}
3776 	}
3777 	*last_publ = 0;
3778 
3779 	return 0;
3780 }
3781 
3782 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
3783 {
3784 	int err;
3785 	u32 tsk_portid = cb->args[0];
3786 	u32 last_publ = cb->args[1];
3787 	u32 done = cb->args[2];
3788 	struct net *net = sock_net(skb->sk);
3789 	struct tipc_sock *tsk;
3790 
3791 	if (!tsk_portid) {
3792 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
3793 		struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
3794 
3795 		if (!attrs[TIPC_NLA_SOCK])
3796 			return -EINVAL;
3797 
3798 		err = nla_parse_nested_deprecated(sock, TIPC_NLA_SOCK_MAX,
3799 						  attrs[TIPC_NLA_SOCK],
3800 						  tipc_nl_sock_policy, NULL);
3801 		if (err)
3802 			return err;
3803 
3804 		if (!sock[TIPC_NLA_SOCK_REF])
3805 			return -EINVAL;
3806 
3807 		tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
3808 	}
3809 
3810 	if (done)
3811 		return 0;
3812 
3813 	tsk = tipc_sk_lookup(net, tsk_portid);
3814 	if (!tsk)
3815 		return -EINVAL;
3816 
3817 	lock_sock(&tsk->sk);
3818 	err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ);
3819 	if (!err)
3820 		done = 1;
3821 	release_sock(&tsk->sk);
3822 	sock_put(&tsk->sk);
3823 
3824 	cb->args[0] = tsk_portid;
3825 	cb->args[1] = last_publ;
3826 	cb->args[2] = done;
3827 
3828 	return skb->len;
3829 }
3830 
3831 /**
3832  * tipc_sk_filtering - check if a socket should be traced
3833  * @sk: the socket to be examined
3834  *
3835  * @sysctl_tipc_sk_filter is used as the socket tuple for filtering:
3836  * (portid, sock type, name type, name lower, name upper)
3837  *
3838  * Return: true if the socket meets the socket tuple data
3839  * (value 0 = 'any') or when there is no tuple set (all = 0),
3840  * otherwise false
3841  */
3842 bool tipc_sk_filtering(struct sock *sk)
3843 {
3844 	struct tipc_sock *tsk;
3845 	struct publication *p;
3846 	u32 _port, _sktype, _type, _lower, _upper;
3847 	u32 type = 0, lower = 0, upper = 0;
3848 
3849 	if (!sk)
3850 		return true;
3851 
3852 	tsk = tipc_sk(sk);
3853 
3854 	_port = sysctl_tipc_sk_filter[0];
3855 	_sktype = sysctl_tipc_sk_filter[1];
3856 	_type = sysctl_tipc_sk_filter[2];
3857 	_lower = sysctl_tipc_sk_filter[3];
3858 	_upper = sysctl_tipc_sk_filter[4];
3859 
3860 	if (!_port && !_sktype && !_type && !_lower && !_upper)
3861 		return true;
3862 
3863 	if (_port)
3864 		return (_port == tsk->portid);
3865 
3866 	if (_sktype && _sktype != sk->sk_type)
3867 		return false;
3868 
3869 	if (tsk->published) {
3870 		p = list_first_entry_or_null(&tsk->publications,
3871 					     struct publication, binding_sock);
3872 		if (p) {
3873 			type = p->sr.type;
3874 			lower = p->sr.lower;
3875 			upper = p->sr.upper;
3876 		}
3877 	}
3878 
3879 	if (!tipc_sk_type_connectionless(sk)) {
3880 		type = msg_nametype(&tsk->phdr);
3881 		lower = msg_nameinst(&tsk->phdr);
3882 		upper = lower;
3883 	}
3884 
3885 	if ((_type && _type != type) || (_lower && _lower != lower) ||
3886 	    (_upper && _upper != upper))
3887 		return false;
3888 
3889 	return true;
3890 }
3891 
3892 u32 tipc_sock_get_portid(struct sock *sk)
3893 {
3894 	return (sk) ? (tipc_sk(sk))->portid : 0;
3895 }
3896 
3897 /**
3898  * tipc_sk_overlimit1 - check if socket rx queue is about to be overloaded,
3899  *			both the rcv and backlog queues are considered
3900  * @sk: tipc sk to be checked
3901  * @skb: tipc msg to be checked
3902  *
3903  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3904  */
3905 
3906 bool tipc_sk_overlimit1(struct sock *sk, struct sk_buff *skb)
3907 {
3908 	atomic_t *dcnt = &tipc_sk(sk)->dupl_rcvcnt;
3909 	unsigned int lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
3910 	unsigned int qsize = sk->sk_backlog.len + sk_rmem_alloc_get(sk);
3911 
3912 	return (qsize > lim * 90 / 100);
3913 }
3914 
3915 /**
3916  * tipc_sk_overlimit2 - check if socket rx queue is about to be overloaded,
3917  *			only the rcv queue is considered
3918  * @sk: tipc sk to be checked
3919  * @skb: tipc msg to be checked
3920  *
3921  * Return: true if the socket rx queue allocation is > 90%, otherwise false
3922  */
3923 
3924 bool tipc_sk_overlimit2(struct sock *sk, struct sk_buff *skb)
3925 {
3926 	unsigned int lim = rcvbuf_limit(sk, skb);
3927 	unsigned int qsize = sk_rmem_alloc_get(sk);
3928 
3929 	return (qsize > lim * 90 / 100);
3930 }
3931 
3932 /**
3933  * tipc_sk_dump - dump TIPC socket
3934  * @sk: tipc sk to be dumped
3935  * @dqueues: bitmask to decide if any socket queue to be dumped?
3936  *           - TIPC_DUMP_NONE: don't dump socket queues
3937  *           - TIPC_DUMP_SK_SNDQ: dump socket send queue
3938  *           - TIPC_DUMP_SK_RCVQ: dump socket rcv queue
3939  *           - TIPC_DUMP_SK_BKLGQ: dump socket backlog queue
3940  *           - TIPC_DUMP_ALL: dump all the socket queues above
3941  * @buf: returned buffer of dump data in format
3942  */
3943 int tipc_sk_dump(struct sock *sk, u16 dqueues, char *buf)
3944 {
3945 	int i = 0;
3946 	size_t sz = (dqueues) ? SK_LMAX : SK_LMIN;
3947 	u32 conn_type, conn_instance;
3948 	struct tipc_sock *tsk;
3949 	struct publication *p;
3950 	bool tsk_connected;
3951 
3952 	if (!sk) {
3953 		i += scnprintf(buf, sz, "sk data: (null)\n");
3954 		return i;
3955 	}
3956 
3957 	tsk = tipc_sk(sk);
3958 	tsk_connected = !tipc_sk_type_connectionless(sk);
3959 
3960 	i += scnprintf(buf, sz, "sk data: %u", sk->sk_type);
3961 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_state);
3962 	i += scnprintf(buf + i, sz - i, " %x", tsk_own_node(tsk));
3963 	i += scnprintf(buf + i, sz - i, " %u", tsk->portid);
3964 	i += scnprintf(buf + i, sz - i, " | %u", tsk_connected);
3965 	if (tsk_connected) {
3966 		i += scnprintf(buf + i, sz - i, " %x", tsk_peer_node(tsk));
3967 		i += scnprintf(buf + i, sz - i, " %u", tsk_peer_port(tsk));
3968 		conn_type = msg_nametype(&tsk->phdr);
3969 		conn_instance = msg_nameinst(&tsk->phdr);
3970 		i += scnprintf(buf + i, sz - i, " %u", conn_type);
3971 		i += scnprintf(buf + i, sz - i, " %u", conn_instance);
3972 	}
3973 	i += scnprintf(buf + i, sz - i, " | %u", tsk->published);
3974 	if (tsk->published) {
3975 		p = list_first_entry_or_null(&tsk->publications,
3976 					     struct publication, binding_sock);
3977 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.type : 0);
3978 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.lower : 0);
3979 		i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.upper : 0);
3980 	}
3981 	i += scnprintf(buf + i, sz - i, " | %u", tsk->snd_win);
3982 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_win);
3983 	i += scnprintf(buf + i, sz - i, " %u", tsk->max_pkt);
3984 	i += scnprintf(buf + i, sz - i, " %x", tsk->peer_caps);
3985 	i += scnprintf(buf + i, sz - i, " %u", tsk->cong_link_cnt);
3986 	i += scnprintf(buf + i, sz - i, " %u", tsk->snt_unacked);
3987 	i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_unacked);
3988 	i += scnprintf(buf + i, sz - i, " %u", atomic_read(&tsk->dupl_rcvcnt));
3989 	i += scnprintf(buf + i, sz - i, " %u", sk->sk_shutdown);
3990 	i += scnprintf(buf + i, sz - i, " | %d", sk_wmem_alloc_get(sk));
3991 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_sndbuf);
3992 	i += scnprintf(buf + i, sz - i, " | %d", sk_rmem_alloc_get(sk));
3993 	i += scnprintf(buf + i, sz - i, " %d", sk->sk_rcvbuf);
3994 	i += scnprintf(buf + i, sz - i, " | %d\n", READ_ONCE(sk->sk_backlog.len));
3995 
3996 	if (dqueues & TIPC_DUMP_SK_SNDQ) {
3997 		i += scnprintf(buf + i, sz - i, "sk_write_queue: ");
3998 		i += tipc_list_dump(&sk->sk_write_queue, false, buf + i);
3999 	}
4000 
4001 	if (dqueues & TIPC_DUMP_SK_RCVQ) {
4002 		i += scnprintf(buf + i, sz - i, "sk_receive_queue: ");
4003 		i += tipc_list_dump(&sk->sk_receive_queue, false, buf + i);
4004 	}
4005 
4006 	if (dqueues & TIPC_DUMP_SK_BKLGQ) {
4007 		i += scnprintf(buf + i, sz - i, "sk_backlog:\n  head ");
4008 		i += tipc_skb_dump(sk->sk_backlog.head, false, buf + i);
4009 		if (sk->sk_backlog.tail != sk->sk_backlog.head) {
4010 			i += scnprintf(buf + i, sz - i, "  tail ");
4011 			i += tipc_skb_dump(sk->sk_backlog.tail, false,
4012 					   buf + i);
4013 		}
4014 	}
4015 
4016 	return i;
4017 }
4018