xref: /linux/net/mptcp/pm.c (revision 2151003e773c7e7dba4d64bed4bfc483681b5f6a)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Multipath TCP
3  *
4  * Copyright (c) 2019, Intel Corporation.
5  */
6 #define pr_fmt(fmt) "MPTCP: " fmt
7 
8 #include <linux/kernel.h>
9 #include <net/mptcp.h>
10 #include "protocol.h"
11 
12 #include "mib.h"
13 #include "mptcp_pm_gen.h"
14 
15 /* path manager command handlers */
16 
17 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
18 			   const struct mptcp_addr_info *addr,
19 			   bool echo)
20 {
21 	u8 add_addr = READ_ONCE(msk->pm.addr_signal);
22 
23 	pr_debug("msk=%p, local_id=%d, echo=%d\n", msk, addr->id, echo);
24 
25 	lockdep_assert_held(&msk->pm.lock);
26 
27 	if (add_addr &
28 	    (echo ? BIT(MPTCP_ADD_ADDR_ECHO) : BIT(MPTCP_ADD_ADDR_SIGNAL))) {
29 		MPTCP_INC_STATS(sock_net((struct sock *)msk),
30 				echo ? MPTCP_MIB_ECHOADDTXDROP : MPTCP_MIB_ADDADDRTXDROP);
31 		return -EINVAL;
32 	}
33 
34 	if (echo) {
35 		msk->pm.remote = *addr;
36 		add_addr |= BIT(MPTCP_ADD_ADDR_ECHO);
37 	} else {
38 		msk->pm.local = *addr;
39 		add_addr |= BIT(MPTCP_ADD_ADDR_SIGNAL);
40 	}
41 	WRITE_ONCE(msk->pm.addr_signal, add_addr);
42 	return 0;
43 }
44 
45 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list)
46 {
47 	u8 rm_addr = READ_ONCE(msk->pm.addr_signal);
48 
49 	pr_debug("msk=%p, rm_list_nr=%d\n", msk, rm_list->nr);
50 
51 	if (rm_addr) {
52 		MPTCP_ADD_STATS(sock_net((struct sock *)msk),
53 				MPTCP_MIB_RMADDRTXDROP, rm_list->nr);
54 		return -EINVAL;
55 	}
56 
57 	msk->pm.rm_list_tx = *rm_list;
58 	rm_addr |= BIT(MPTCP_RM_ADDR_SIGNAL);
59 	WRITE_ONCE(msk->pm.addr_signal, rm_addr);
60 	mptcp_pm_nl_addr_send_ack(msk);
61 	return 0;
62 }
63 
64 /* path manager event handlers */
65 
66 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side)
67 {
68 	struct mptcp_pm_data *pm = &msk->pm;
69 
70 	pr_debug("msk=%p, token=%u side=%d\n", msk, READ_ONCE(msk->token), server_side);
71 
72 	WRITE_ONCE(pm->server_side, server_side);
73 	mptcp_event(MPTCP_EVENT_CREATED, msk, ssk, GFP_ATOMIC);
74 }
75 
76 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
77 {
78 	struct mptcp_pm_data *pm = &msk->pm;
79 	unsigned int subflows_max;
80 	int ret = 0;
81 
82 	if (mptcp_pm_is_userspace(msk)) {
83 		if (mptcp_userspace_pm_active(msk)) {
84 			spin_lock_bh(&pm->lock);
85 			pm->subflows++;
86 			spin_unlock_bh(&pm->lock);
87 			return true;
88 		}
89 		return false;
90 	}
91 
92 	subflows_max = mptcp_pm_get_subflows_max(msk);
93 
94 	pr_debug("msk=%p subflows=%d max=%d allow=%d\n", msk, pm->subflows,
95 		 subflows_max, READ_ONCE(pm->accept_subflow));
96 
97 	/* try to avoid acquiring the lock below */
98 	if (!READ_ONCE(pm->accept_subflow))
99 		return false;
100 
101 	spin_lock_bh(&pm->lock);
102 	if (READ_ONCE(pm->accept_subflow)) {
103 		ret = pm->subflows < subflows_max;
104 		if (ret && ++pm->subflows == subflows_max)
105 			WRITE_ONCE(pm->accept_subflow, false);
106 	}
107 	spin_unlock_bh(&pm->lock);
108 
109 	return ret;
110 }
111 
112 /* return true if the new status bit is currently cleared, that is, this event
113  * can be server, eventually by an already scheduled work
114  */
115 static bool mptcp_pm_schedule_work(struct mptcp_sock *msk,
116 				   enum mptcp_pm_status new_status)
117 {
118 	pr_debug("msk=%p status=%x new=%lx\n", msk, msk->pm.status,
119 		 BIT(new_status));
120 	if (msk->pm.status & BIT(new_status))
121 		return false;
122 
123 	msk->pm.status |= BIT(new_status);
124 	mptcp_schedule_work((struct sock *)msk);
125 	return true;
126 }
127 
128 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk)
129 {
130 	struct mptcp_pm_data *pm = &msk->pm;
131 	bool announce = false;
132 
133 	pr_debug("msk=%p\n", msk);
134 
135 	spin_lock_bh(&pm->lock);
136 
137 	/* mptcp_pm_fully_established() can be invoked by multiple
138 	 * racing paths - accept() and check_fully_established()
139 	 * be sure to serve this event only once.
140 	 */
141 	if (READ_ONCE(pm->work_pending) &&
142 	    !(msk->pm.status & BIT(MPTCP_PM_ALREADY_ESTABLISHED)))
143 		mptcp_pm_schedule_work(msk, MPTCP_PM_ESTABLISHED);
144 
145 	if ((msk->pm.status & BIT(MPTCP_PM_ALREADY_ESTABLISHED)) == 0)
146 		announce = true;
147 
148 	msk->pm.status |= BIT(MPTCP_PM_ALREADY_ESTABLISHED);
149 	spin_unlock_bh(&pm->lock);
150 
151 	if (announce)
152 		mptcp_event(MPTCP_EVENT_ESTABLISHED, msk, ssk, GFP_ATOMIC);
153 }
154 
155 void mptcp_pm_connection_closed(struct mptcp_sock *msk)
156 {
157 	pr_debug("msk=%p\n", msk);
158 
159 	if (msk->token)
160 		mptcp_event(MPTCP_EVENT_CLOSED, msk, NULL, GFP_KERNEL);
161 }
162 
163 void mptcp_pm_subflow_established(struct mptcp_sock *msk)
164 {
165 	struct mptcp_pm_data *pm = &msk->pm;
166 
167 	pr_debug("msk=%p\n", msk);
168 
169 	if (!READ_ONCE(pm->work_pending))
170 		return;
171 
172 	spin_lock_bh(&pm->lock);
173 
174 	if (READ_ONCE(pm->work_pending))
175 		mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
176 
177 	spin_unlock_bh(&pm->lock);
178 }
179 
180 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk,
181 				 const struct mptcp_subflow_context *subflow)
182 {
183 	struct mptcp_pm_data *pm = &msk->pm;
184 	bool update_subflows;
185 
186 	update_subflows = subflow->request_join || subflow->mp_join;
187 	if (mptcp_pm_is_userspace(msk)) {
188 		if (update_subflows) {
189 			spin_lock_bh(&pm->lock);
190 			pm->subflows--;
191 			spin_unlock_bh(&pm->lock);
192 		}
193 		return;
194 	}
195 
196 	if (!READ_ONCE(pm->work_pending) && !update_subflows)
197 		return;
198 
199 	spin_lock_bh(&pm->lock);
200 	if (update_subflows)
201 		__mptcp_pm_close_subflow(msk);
202 
203 	/* Even if this subflow is not really established, tell the PM to try
204 	 * to pick the next ones, if possible.
205 	 */
206 	if (mptcp_pm_nl_check_work_pending(msk))
207 		mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
208 
209 	spin_unlock_bh(&pm->lock);
210 }
211 
212 void mptcp_pm_add_addr_received(const struct sock *ssk,
213 				const struct mptcp_addr_info *addr)
214 {
215 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
216 	struct mptcp_sock *msk = mptcp_sk(subflow->conn);
217 	struct mptcp_pm_data *pm = &msk->pm;
218 
219 	pr_debug("msk=%p remote_id=%d accept=%d\n", msk, addr->id,
220 		 READ_ONCE(pm->accept_addr));
221 
222 	mptcp_event_addr_announced(ssk, addr);
223 
224 	spin_lock_bh(&pm->lock);
225 
226 	if (mptcp_pm_is_userspace(msk)) {
227 		if (mptcp_userspace_pm_active(msk)) {
228 			mptcp_pm_announce_addr(msk, addr, true);
229 			mptcp_pm_add_addr_send_ack(msk);
230 		} else {
231 			__MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_ADDADDRDROP);
232 		}
233 	/* id0 should not have a different address */
234 	} else if ((addr->id == 0 && !mptcp_pm_nl_is_init_remote_addr(msk, addr)) ||
235 		   (addr->id > 0 && !READ_ONCE(pm->accept_addr))) {
236 		mptcp_pm_announce_addr(msk, addr, true);
237 		mptcp_pm_add_addr_send_ack(msk);
238 	} else if (mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED)) {
239 		pm->remote = *addr;
240 	} else {
241 		__MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_ADDADDRDROP);
242 	}
243 
244 	spin_unlock_bh(&pm->lock);
245 }
246 
247 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
248 			      const struct mptcp_addr_info *addr)
249 {
250 	struct mptcp_pm_data *pm = &msk->pm;
251 
252 	pr_debug("msk=%p\n", msk);
253 
254 	spin_lock_bh(&pm->lock);
255 
256 	if (mptcp_lookup_anno_list_by_saddr(msk, addr) && READ_ONCE(pm->work_pending))
257 		mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
258 
259 	spin_unlock_bh(&pm->lock);
260 }
261 
262 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk)
263 {
264 	if (!mptcp_pm_should_add_signal(msk))
265 		return;
266 
267 	mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_SEND_ACK);
268 }
269 
270 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
271 			       const struct mptcp_rm_list *rm_list)
272 {
273 	struct mptcp_pm_data *pm = &msk->pm;
274 	u8 i;
275 
276 	pr_debug("msk=%p remote_ids_nr=%d\n", msk, rm_list->nr);
277 
278 	for (i = 0; i < rm_list->nr; i++)
279 		mptcp_event_addr_removed(msk, rm_list->ids[i]);
280 
281 	spin_lock_bh(&pm->lock);
282 	if (mptcp_pm_schedule_work(msk, MPTCP_PM_RM_ADDR_RECEIVED))
283 		pm->rm_list_rx = *rm_list;
284 	else
285 		__MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_RMADDRDROP);
286 	spin_unlock_bh(&pm->lock);
287 }
288 
289 void mptcp_pm_mp_prio_received(struct sock *ssk, u8 bkup)
290 {
291 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
292 	struct sock *sk = subflow->conn;
293 	struct mptcp_sock *msk;
294 
295 	pr_debug("subflow->backup=%d, bkup=%d\n", subflow->backup, bkup);
296 	msk = mptcp_sk(sk);
297 	if (subflow->backup != bkup)
298 		subflow->backup = bkup;
299 
300 	mptcp_event(MPTCP_EVENT_SUB_PRIORITY, msk, ssk, GFP_ATOMIC);
301 }
302 
303 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq)
304 {
305 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
306 	struct mptcp_sock *msk = mptcp_sk(subflow->conn);
307 
308 	pr_debug("fail_seq=%llu\n", fail_seq);
309 
310 	if (!READ_ONCE(msk->allow_infinite_fallback))
311 		return;
312 
313 	if (!subflow->fail_tout) {
314 		pr_debug("send MP_FAIL response and infinite map\n");
315 
316 		subflow->send_mp_fail = 1;
317 		subflow->send_infinite_map = 1;
318 		tcp_send_ack(sk);
319 	} else {
320 		pr_debug("MP_FAIL response received\n");
321 		WRITE_ONCE(subflow->fail_tout, 0);
322 	}
323 }
324 
325 /* path manager helpers */
326 
327 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
328 			      unsigned int opt_size, unsigned int remaining,
329 			      struct mptcp_addr_info *addr, bool *echo,
330 			      bool *drop_other_suboptions)
331 {
332 	int ret = false;
333 	u8 add_addr;
334 	u8 family;
335 	bool port;
336 
337 	spin_lock_bh(&msk->pm.lock);
338 
339 	/* double check after the lock is acquired */
340 	if (!mptcp_pm_should_add_signal(msk))
341 		goto out_unlock;
342 
343 	/* always drop every other options for pure ack ADD_ADDR; this is a
344 	 * plain dup-ack from TCP perspective. The other MPTCP-relevant info,
345 	 * if any, will be carried by the 'original' TCP ack
346 	 */
347 	if (skb && skb_is_tcp_pure_ack(skb)) {
348 		remaining += opt_size;
349 		*drop_other_suboptions = true;
350 	}
351 
352 	*echo = mptcp_pm_should_add_signal_echo(msk);
353 	port = !!(*echo ? msk->pm.remote.port : msk->pm.local.port);
354 
355 	family = *echo ? msk->pm.remote.family : msk->pm.local.family;
356 	if (remaining < mptcp_add_addr_len(family, *echo, port))
357 		goto out_unlock;
358 
359 	if (*echo) {
360 		*addr = msk->pm.remote;
361 		add_addr = msk->pm.addr_signal & ~BIT(MPTCP_ADD_ADDR_ECHO);
362 	} else {
363 		*addr = msk->pm.local;
364 		add_addr = msk->pm.addr_signal & ~BIT(MPTCP_ADD_ADDR_SIGNAL);
365 	}
366 	WRITE_ONCE(msk->pm.addr_signal, add_addr);
367 	ret = true;
368 
369 out_unlock:
370 	spin_unlock_bh(&msk->pm.lock);
371 	return ret;
372 }
373 
374 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
375 			     struct mptcp_rm_list *rm_list)
376 {
377 	int ret = false, len;
378 	u8 rm_addr;
379 
380 	spin_lock_bh(&msk->pm.lock);
381 
382 	/* double check after the lock is acquired */
383 	if (!mptcp_pm_should_rm_signal(msk))
384 		goto out_unlock;
385 
386 	rm_addr = msk->pm.addr_signal & ~BIT(MPTCP_RM_ADDR_SIGNAL);
387 	len = mptcp_rm_addr_len(&msk->pm.rm_list_tx);
388 	if (len < 0) {
389 		WRITE_ONCE(msk->pm.addr_signal, rm_addr);
390 		goto out_unlock;
391 	}
392 	if (remaining < len)
393 		goto out_unlock;
394 
395 	*rm_list = msk->pm.rm_list_tx;
396 	WRITE_ONCE(msk->pm.addr_signal, rm_addr);
397 	ret = true;
398 
399 out_unlock:
400 	spin_unlock_bh(&msk->pm.lock);
401 	return ret;
402 }
403 
404 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
405 {
406 	struct mptcp_addr_info skc_local;
407 	struct mptcp_addr_info msk_local;
408 
409 	if (WARN_ON_ONCE(!msk))
410 		return -1;
411 
412 	/* The 0 ID mapping is defined by the first subflow, copied into the msk
413 	 * addr
414 	 */
415 	mptcp_local_address((struct sock_common *)msk, &msk_local);
416 	mptcp_local_address((struct sock_common *)skc, &skc_local);
417 	if (mptcp_addresses_equal(&msk_local, &skc_local, false))
418 		return 0;
419 
420 	if (mptcp_pm_is_userspace(msk))
421 		return mptcp_userspace_pm_get_local_id(msk, &skc_local);
422 	return mptcp_pm_nl_get_local_id(msk, &skc_local);
423 }
424 
425 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc)
426 {
427 	struct mptcp_addr_info skc_local;
428 
429 	mptcp_local_address((struct sock_common *)skc, &skc_local);
430 
431 	if (mptcp_pm_is_userspace(msk))
432 		return mptcp_userspace_pm_is_backup(msk, &skc_local);
433 
434 	return mptcp_pm_nl_is_backup(msk, &skc_local);
435 }
436 
437 static int mptcp_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
438 			     struct genl_info *info)
439 {
440 	if (info->attrs[MPTCP_PM_ATTR_TOKEN])
441 		return mptcp_userspace_pm_get_addr(id, addr, info);
442 	return mptcp_pm_nl_get_addr(id, addr, info);
443 }
444 
445 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info)
446 {
447 	struct mptcp_pm_addr_entry addr;
448 	struct nlattr *attr;
449 	struct sk_buff *msg;
450 	void *reply;
451 	int ret;
452 
453 	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ENDPOINT_ADDR))
454 		return -EINVAL;
455 
456 	attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
457 	ret = mptcp_pm_parse_entry(attr, info, false, &addr);
458 	if (ret < 0)
459 		return ret;
460 
461 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
462 	if (!msg)
463 		return -ENOMEM;
464 
465 	reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
466 				  info->genlhdr->cmd);
467 	if (!reply) {
468 		GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
469 		ret = -EMSGSIZE;
470 		goto fail;
471 	}
472 
473 	ret = mptcp_pm_get_addr(addr.addr.id, &addr, info);
474 	if (ret) {
475 		NL_SET_ERR_MSG_ATTR(info->extack, attr, "address not found");
476 		goto fail;
477 	}
478 
479 	ret = mptcp_nl_fill_addr(msg, &addr);
480 	if (ret)
481 		goto fail;
482 
483 	genlmsg_end(msg, reply);
484 	ret = genlmsg_reply(msg, info);
485 	return ret;
486 
487 fail:
488 	nlmsg_free(msg);
489 	return ret;
490 }
491 
492 static int mptcp_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb)
493 {
494 	const struct genl_info *info = genl_info_dump(cb);
495 
496 	if (info->attrs[MPTCP_PM_ATTR_TOKEN])
497 		return mptcp_userspace_pm_dump_addr(msg, cb);
498 	return mptcp_pm_nl_dump_addr(msg, cb);
499 }
500 
501 int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
502 				struct netlink_callback *cb)
503 {
504 	return mptcp_pm_dump_addr(msg, cb);
505 }
506 
507 static int mptcp_pm_set_flags(struct genl_info *info)
508 {
509 	struct mptcp_pm_addr_entry loc = { .addr = { .family = AF_UNSPEC }, };
510 	struct nlattr *attr_loc;
511 	int ret = -EINVAL;
512 
513 	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR))
514 		return ret;
515 
516 	attr_loc = info->attrs[MPTCP_PM_ATTR_ADDR];
517 	ret = mptcp_pm_parse_entry(attr_loc, info, false, &loc);
518 	if (ret < 0)
519 		return ret;
520 
521 	if (info->attrs[MPTCP_PM_ATTR_TOKEN])
522 		return mptcp_userspace_pm_set_flags(&loc, info);
523 	return mptcp_pm_nl_set_flags(&loc, info);
524 }
525 
526 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info)
527 {
528 	return mptcp_pm_set_flags(info);
529 }
530 
531 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk)
532 {
533 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
534 	u32 rcv_tstamp = READ_ONCE(tcp_sk(ssk)->rcv_tstamp);
535 
536 	/* keep track of rtx periods with no progress */
537 	if (!subflow->stale_count) {
538 		subflow->stale_rcv_tstamp = rcv_tstamp;
539 		subflow->stale_count++;
540 	} else if (subflow->stale_rcv_tstamp == rcv_tstamp) {
541 		if (subflow->stale_count < U8_MAX)
542 			subflow->stale_count++;
543 		mptcp_pm_nl_subflow_chk_stale(msk, ssk);
544 	} else {
545 		subflow->stale_count = 0;
546 		mptcp_subflow_set_active(subflow);
547 	}
548 }
549 
550 /* if sk is ipv4 or ipv6_only allows only same-family local and remote addresses,
551  * otherwise allow any matching local/remote pair
552  */
553 bool mptcp_pm_addr_families_match(const struct sock *sk,
554 				  const struct mptcp_addr_info *loc,
555 				  const struct mptcp_addr_info *rem)
556 {
557 	bool mptcp_is_v4 = sk->sk_family == AF_INET;
558 
559 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
560 	bool loc_is_v4 = loc->family == AF_INET || ipv6_addr_v4mapped(&loc->addr6);
561 	bool rem_is_v4 = rem->family == AF_INET || ipv6_addr_v4mapped(&rem->addr6);
562 
563 	if (mptcp_is_v4)
564 		return loc_is_v4 && rem_is_v4;
565 
566 	if (ipv6_only_sock(sk))
567 		return !loc_is_v4 && !rem_is_v4;
568 
569 	return loc_is_v4 == rem_is_v4;
570 #else
571 	return mptcp_is_v4 && loc->family == AF_INET && rem->family == AF_INET;
572 #endif
573 }
574 
575 void mptcp_pm_data_reset(struct mptcp_sock *msk)
576 {
577 	u8 pm_type = mptcp_get_pm_type(sock_net((struct sock *)msk));
578 	struct mptcp_pm_data *pm = &msk->pm;
579 
580 	pm->add_addr_signaled = 0;
581 	pm->add_addr_accepted = 0;
582 	pm->local_addr_used = 0;
583 	pm->subflows = 0;
584 	pm->rm_list_tx.nr = 0;
585 	pm->rm_list_rx.nr = 0;
586 	WRITE_ONCE(pm->pm_type, pm_type);
587 
588 	if (pm_type == MPTCP_PM_TYPE_KERNEL) {
589 		bool subflows_allowed = !!mptcp_pm_get_subflows_max(msk);
590 
591 		/* pm->work_pending must be only be set to 'true' when
592 		 * pm->pm_type is set to MPTCP_PM_TYPE_KERNEL
593 		 */
594 		WRITE_ONCE(pm->work_pending,
595 			   (!!mptcp_pm_get_local_addr_max(msk) &&
596 			    subflows_allowed) ||
597 			   !!mptcp_pm_get_add_addr_signal_max(msk));
598 		WRITE_ONCE(pm->accept_addr,
599 			   !!mptcp_pm_get_add_addr_accept_max(msk) &&
600 			   subflows_allowed);
601 		WRITE_ONCE(pm->accept_subflow, subflows_allowed);
602 	} else {
603 		WRITE_ONCE(pm->work_pending, 0);
604 		WRITE_ONCE(pm->accept_addr, 0);
605 		WRITE_ONCE(pm->accept_subflow, 0);
606 	}
607 
608 	WRITE_ONCE(pm->addr_signal, 0);
609 	WRITE_ONCE(pm->remote_deny_join_id0, false);
610 	pm->status = 0;
611 	bitmap_fill(msk->pm.id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
612 }
613 
614 void mptcp_pm_data_init(struct mptcp_sock *msk)
615 {
616 	spin_lock_init(&msk->pm.lock);
617 	INIT_LIST_HEAD(&msk->pm.anno_list);
618 	INIT_LIST_HEAD(&msk->pm.userspace_pm_local_addr_list);
619 	mptcp_pm_data_reset(msk);
620 }
621 
622 void __init mptcp_pm_init(void)
623 {
624 	mptcp_pm_nl_init();
625 }
626