xref: /openbmc/linux/net/bluetooth/l2cap_sock.c (revision db181ce0)
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (C) 2000-2001 Qualcomm Incorporated
4    Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5    Copyright (C) 2010 Google Inc.
6    Copyright (C) 2011 ProFUSION Embedded Systems
7 
8    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
9 
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License version 2 as
12    published by the Free Software Foundation;
13 
14    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
17    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
18    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
19    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
21    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22 
23    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
24    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
25    SOFTWARE IS DISCLAIMED.
26 */
27 
28 /* Bluetooth L2CAP sockets. */
29 
30 #include <linux/module.h>
31 #include <linux/export.h>
32 
33 #include <net/bluetooth/bluetooth.h>
34 #include <net/bluetooth/hci_core.h>
35 #include <net/bluetooth/l2cap.h>
36 
37 #include "smp.h"
38 
39 static struct bt_sock_list l2cap_sk_list = {
40 	.lock = __RW_LOCK_UNLOCKED(l2cap_sk_list.lock)
41 };
42 
43 static const struct proto_ops l2cap_sock_ops;
44 static void l2cap_sock_init(struct sock *sk, struct sock *parent);
45 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
46 				     int proto, gfp_t prio);
47 
48 bool l2cap_is_socket(struct socket *sock)
49 {
50 	return sock && sock->ops == &l2cap_sock_ops;
51 }
52 EXPORT_SYMBOL(l2cap_is_socket);
53 
54 static int l2cap_validate_bredr_psm(u16 psm)
55 {
56 	/* PSM must be odd and lsb of upper byte must be 0 */
57 	if ((psm & 0x0101) != 0x0001)
58 		return -EINVAL;
59 
60 	/* Restrict usage of well-known PSMs */
61 	if (psm < 0x1001 && !capable(CAP_NET_BIND_SERVICE))
62 		return -EACCES;
63 
64 	return 0;
65 }
66 
67 static int l2cap_validate_le_psm(u16 psm)
68 {
69 	/* Valid LE_PSM ranges are defined only until 0x00ff */
70 	if (psm > 0x00ff)
71 		return -EINVAL;
72 
73 	/* Restrict fixed, SIG assigned PSM values to CAP_NET_BIND_SERVICE */
74 	if (psm <= 0x007f && !capable(CAP_NET_BIND_SERVICE))
75 		return -EACCES;
76 
77 	return 0;
78 }
79 
80 static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
81 {
82 	struct sock *sk = sock->sk;
83 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
84 	struct sockaddr_l2 la;
85 	int len, err = 0;
86 
87 	BT_DBG("sk %p", sk);
88 
89 	if (!addr || addr->sa_family != AF_BLUETOOTH)
90 		return -EINVAL;
91 
92 	memset(&la, 0, sizeof(la));
93 	len = min_t(unsigned int, sizeof(la), alen);
94 	memcpy(&la, addr, len);
95 
96 	if (la.l2_cid && la.l2_psm)
97 		return -EINVAL;
98 
99 	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
100 		return -EINVAL;
101 
102 	if (la.l2_cid) {
103 		/* When the socket gets created it defaults to
104 		 * CHAN_CONN_ORIENTED, so we need to overwrite the
105 		 * default here.
106 		 */
107 		chan->chan_type = L2CAP_CHAN_FIXED;
108 		chan->omtu = L2CAP_DEFAULT_MTU;
109 	}
110 
111 	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
112 		/* We only allow ATT user space socket */
113 		if (la.l2_cid &&
114 		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
115 			return -EINVAL;
116 	}
117 
118 	lock_sock(sk);
119 
120 	if (sk->sk_state != BT_OPEN) {
121 		err = -EBADFD;
122 		goto done;
123 	}
124 
125 	if (la.l2_psm) {
126 		__u16 psm = __le16_to_cpu(la.l2_psm);
127 
128 		if (la.l2_bdaddr_type == BDADDR_BREDR)
129 			err = l2cap_validate_bredr_psm(psm);
130 		else
131 			err = l2cap_validate_le_psm(psm);
132 
133 		if (err)
134 			goto done;
135 	}
136 
137 	if (la.l2_cid)
138 		err = l2cap_add_scid(chan, __le16_to_cpu(la.l2_cid));
139 	else
140 		err = l2cap_add_psm(chan, &la.l2_bdaddr, la.l2_psm);
141 
142 	if (err < 0)
143 		goto done;
144 
145 	switch (chan->chan_type) {
146 	case L2CAP_CHAN_CONN_LESS:
147 		if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_3DSP)
148 			chan->sec_level = BT_SECURITY_SDP;
149 		break;
150 	case L2CAP_CHAN_CONN_ORIENTED:
151 		if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_SDP ||
152 		    __le16_to_cpu(la.l2_psm) == L2CAP_PSM_RFCOMM)
153 			chan->sec_level = BT_SECURITY_SDP;
154 		break;
155 	case L2CAP_CHAN_RAW:
156 		chan->sec_level = BT_SECURITY_SDP;
157 		break;
158 	}
159 
160 	bacpy(&chan->src, &la.l2_bdaddr);
161 	chan->src_type = la.l2_bdaddr_type;
162 
163 	if (chan->psm && bdaddr_type_is_le(chan->src_type))
164 		chan->mode = L2CAP_MODE_LE_FLOWCTL;
165 
166 	chan->state = BT_BOUND;
167 	sk->sk_state = BT_BOUND;
168 
169 done:
170 	release_sock(sk);
171 	return err;
172 }
173 
174 static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr,
175 			      int alen, int flags)
176 {
177 	struct sock *sk = sock->sk;
178 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
179 	struct sockaddr_l2 la;
180 	int len, err = 0;
181 
182 	BT_DBG("sk %p", sk);
183 
184 	if (!addr || alen < sizeof(addr->sa_family) ||
185 	    addr->sa_family != AF_BLUETOOTH)
186 		return -EINVAL;
187 
188 	memset(&la, 0, sizeof(la));
189 	len = min_t(unsigned int, sizeof(la), alen);
190 	memcpy(&la, addr, len);
191 
192 	if (la.l2_cid && la.l2_psm)
193 		return -EINVAL;
194 
195 	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
196 		return -EINVAL;
197 
198 	/* Check that the socket wasn't bound to something that
199 	 * conflicts with the address given to connect(). If chan->src
200 	 * is BDADDR_ANY it means bind() was never used, in which case
201 	 * chan->src_type and la.l2_bdaddr_type do not need to match.
202 	 */
203 	if (chan->src_type == BDADDR_BREDR && bacmp(&chan->src, BDADDR_ANY) &&
204 	    bdaddr_type_is_le(la.l2_bdaddr_type)) {
205 		/* Old user space versions will try to incorrectly bind
206 		 * the ATT socket using BDADDR_BREDR. We need to accept
207 		 * this and fix up the source address type only when
208 		 * both the source CID and destination CID indicate
209 		 * ATT. Anything else is an invalid combination.
210 		 */
211 		if (chan->scid != L2CAP_CID_ATT ||
212 		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
213 			return -EINVAL;
214 
215 		/* We don't have the hdev available here to make a
216 		 * better decision on random vs public, but since all
217 		 * user space versions that exhibit this issue anyway do
218 		 * not support random local addresses assuming public
219 		 * here is good enough.
220 		 */
221 		chan->src_type = BDADDR_LE_PUBLIC;
222 	}
223 
224 	if (chan->src_type != BDADDR_BREDR && la.l2_bdaddr_type == BDADDR_BREDR)
225 		return -EINVAL;
226 
227 	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
228 		/* We only allow ATT user space socket */
229 		if (la.l2_cid &&
230 		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
231 			return -EINVAL;
232 	}
233 
234 	if (chan->psm && bdaddr_type_is_le(chan->src_type))
235 		chan->mode = L2CAP_MODE_LE_FLOWCTL;
236 
237 	err = l2cap_chan_connect(chan, la.l2_psm, __le16_to_cpu(la.l2_cid),
238 				 &la.l2_bdaddr, la.l2_bdaddr_type);
239 	if (err)
240 		return err;
241 
242 	lock_sock(sk);
243 
244 	err = bt_sock_wait_state(sk, BT_CONNECTED,
245 				 sock_sndtimeo(sk, flags & O_NONBLOCK));
246 
247 	release_sock(sk);
248 
249 	return err;
250 }
251 
252 static int l2cap_sock_listen(struct socket *sock, int backlog)
253 {
254 	struct sock *sk = sock->sk;
255 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
256 	int err = 0;
257 
258 	BT_DBG("sk %p backlog %d", sk, backlog);
259 
260 	lock_sock(sk);
261 
262 	if (sk->sk_state != BT_BOUND) {
263 		err = -EBADFD;
264 		goto done;
265 	}
266 
267 	if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM) {
268 		err = -EINVAL;
269 		goto done;
270 	}
271 
272 	switch (chan->mode) {
273 	case L2CAP_MODE_BASIC:
274 	case L2CAP_MODE_LE_FLOWCTL:
275 		break;
276 	case L2CAP_MODE_ERTM:
277 	case L2CAP_MODE_STREAMING:
278 		if (!disable_ertm)
279 			break;
280 		/* fall through */
281 	default:
282 		err = -ENOTSUPP;
283 		goto done;
284 	}
285 
286 	sk->sk_max_ack_backlog = backlog;
287 	sk->sk_ack_backlog = 0;
288 
289 	chan->state = BT_LISTEN;
290 	sk->sk_state = BT_LISTEN;
291 
292 done:
293 	release_sock(sk);
294 	return err;
295 }
296 
297 static int l2cap_sock_accept(struct socket *sock, struct socket *newsock,
298 			     int flags)
299 {
300 	DECLARE_WAITQUEUE(wait, current);
301 	struct sock *sk = sock->sk, *nsk;
302 	long timeo;
303 	int err = 0;
304 
305 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
306 
307 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
308 
309 	BT_DBG("sk %p timeo %ld", sk, timeo);
310 
311 	/* Wait for an incoming connection. (wake-one). */
312 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
313 	while (1) {
314 		set_current_state(TASK_INTERRUPTIBLE);
315 
316 		if (sk->sk_state != BT_LISTEN) {
317 			err = -EBADFD;
318 			break;
319 		}
320 
321 		nsk = bt_accept_dequeue(sk, newsock);
322 		if (nsk)
323 			break;
324 
325 		if (!timeo) {
326 			err = -EAGAIN;
327 			break;
328 		}
329 
330 		if (signal_pending(current)) {
331 			err = sock_intr_errno(timeo);
332 			break;
333 		}
334 
335 		release_sock(sk);
336 		timeo = schedule_timeout(timeo);
337 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
338 	}
339 	__set_current_state(TASK_RUNNING);
340 	remove_wait_queue(sk_sleep(sk), &wait);
341 
342 	if (err)
343 		goto done;
344 
345 	newsock->state = SS_CONNECTED;
346 
347 	BT_DBG("new socket %p", nsk);
348 
349 done:
350 	release_sock(sk);
351 	return err;
352 }
353 
354 static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr,
355 			      int *len, int peer)
356 {
357 	struct sockaddr_l2 *la = (struct sockaddr_l2 *) addr;
358 	struct sock *sk = sock->sk;
359 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
360 
361 	BT_DBG("sock %p, sk %p", sock, sk);
362 
363 	if (peer && sk->sk_state != BT_CONNECTED &&
364 	    sk->sk_state != BT_CONNECT && sk->sk_state != BT_CONNECT2)
365 		return -ENOTCONN;
366 
367 	memset(la, 0, sizeof(struct sockaddr_l2));
368 	addr->sa_family = AF_BLUETOOTH;
369 	*len = sizeof(struct sockaddr_l2);
370 
371 	la->l2_psm = chan->psm;
372 
373 	if (peer) {
374 		bacpy(&la->l2_bdaddr, &chan->dst);
375 		la->l2_cid = cpu_to_le16(chan->dcid);
376 		la->l2_bdaddr_type = chan->dst_type;
377 	} else {
378 		bacpy(&la->l2_bdaddr, &chan->src);
379 		la->l2_cid = cpu_to_le16(chan->scid);
380 		la->l2_bdaddr_type = chan->src_type;
381 	}
382 
383 	return 0;
384 }
385 
386 static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
387 				     char __user *optval, int __user *optlen)
388 {
389 	struct sock *sk = sock->sk;
390 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
391 	struct l2cap_options opts;
392 	struct l2cap_conninfo cinfo;
393 	int len, err = 0;
394 	u32 opt;
395 
396 	BT_DBG("sk %p", sk);
397 
398 	if (get_user(len, optlen))
399 		return -EFAULT;
400 
401 	lock_sock(sk);
402 
403 	switch (optname) {
404 	case L2CAP_OPTIONS:
405 		/* LE sockets should use BT_SNDMTU/BT_RCVMTU, but since
406 		 * legacy ATT code depends on getsockopt for
407 		 * L2CAP_OPTIONS we need to let this pass.
408 		 */
409 		if (bdaddr_type_is_le(chan->src_type) &&
410 		    chan->scid != L2CAP_CID_ATT) {
411 			err = -EINVAL;
412 			break;
413 		}
414 
415 		memset(&opts, 0, sizeof(opts));
416 		opts.imtu     = chan->imtu;
417 		opts.omtu     = chan->omtu;
418 		opts.flush_to = chan->flush_to;
419 		opts.mode     = chan->mode;
420 		opts.fcs      = chan->fcs;
421 		opts.max_tx   = chan->max_tx;
422 		opts.txwin_size = chan->tx_win;
423 
424 		len = min_t(unsigned int, len, sizeof(opts));
425 		if (copy_to_user(optval, (char *) &opts, len))
426 			err = -EFAULT;
427 
428 		break;
429 
430 	case L2CAP_LM:
431 		switch (chan->sec_level) {
432 		case BT_SECURITY_LOW:
433 			opt = L2CAP_LM_AUTH;
434 			break;
435 		case BT_SECURITY_MEDIUM:
436 			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT;
437 			break;
438 		case BT_SECURITY_HIGH:
439 			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
440 			      L2CAP_LM_SECURE;
441 			break;
442 		case BT_SECURITY_FIPS:
443 			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
444 			      L2CAP_LM_SECURE | L2CAP_LM_FIPS;
445 			break;
446 		default:
447 			opt = 0;
448 			break;
449 		}
450 
451 		if (test_bit(FLAG_ROLE_SWITCH, &chan->flags))
452 			opt |= L2CAP_LM_MASTER;
453 
454 		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
455 			opt |= L2CAP_LM_RELIABLE;
456 
457 		if (put_user(opt, (u32 __user *) optval))
458 			err = -EFAULT;
459 
460 		break;
461 
462 	case L2CAP_CONNINFO:
463 		if (sk->sk_state != BT_CONNECTED &&
464 		    !(sk->sk_state == BT_CONNECT2 &&
465 		      test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))) {
466 			err = -ENOTCONN;
467 			break;
468 		}
469 
470 		memset(&cinfo, 0, sizeof(cinfo));
471 		cinfo.hci_handle = chan->conn->hcon->handle;
472 		memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3);
473 
474 		len = min_t(unsigned int, len, sizeof(cinfo));
475 		if (copy_to_user(optval, (char *) &cinfo, len))
476 			err = -EFAULT;
477 
478 		break;
479 
480 	default:
481 		err = -ENOPROTOOPT;
482 		break;
483 	}
484 
485 	release_sock(sk);
486 	return err;
487 }
488 
489 static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
490 				 char __user *optval, int __user *optlen)
491 {
492 	struct sock *sk = sock->sk;
493 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
494 	struct bt_security sec;
495 	struct bt_power pwr;
496 	int len, err = 0;
497 
498 	BT_DBG("sk %p", sk);
499 
500 	if (level == SOL_L2CAP)
501 		return l2cap_sock_getsockopt_old(sock, optname, optval, optlen);
502 
503 	if (level != SOL_BLUETOOTH)
504 		return -ENOPROTOOPT;
505 
506 	if (get_user(len, optlen))
507 		return -EFAULT;
508 
509 	lock_sock(sk);
510 
511 	switch (optname) {
512 	case BT_SECURITY:
513 		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
514 		    chan->chan_type != L2CAP_CHAN_FIXED &&
515 		    chan->chan_type != L2CAP_CHAN_RAW) {
516 			err = -EINVAL;
517 			break;
518 		}
519 
520 		memset(&sec, 0, sizeof(sec));
521 		if (chan->conn) {
522 			sec.level = chan->conn->hcon->sec_level;
523 
524 			if (sk->sk_state == BT_CONNECTED)
525 				sec.key_size = chan->conn->hcon->enc_key_size;
526 		} else {
527 			sec.level = chan->sec_level;
528 		}
529 
530 		len = min_t(unsigned int, len, sizeof(sec));
531 		if (copy_to_user(optval, (char *) &sec, len))
532 			err = -EFAULT;
533 
534 		break;
535 
536 	case BT_DEFER_SETUP:
537 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
538 			err = -EINVAL;
539 			break;
540 		}
541 
542 		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
543 			     (u32 __user *) optval))
544 			err = -EFAULT;
545 
546 		break;
547 
548 	case BT_FLUSHABLE:
549 		if (put_user(test_bit(FLAG_FLUSHABLE, &chan->flags),
550 			     (u32 __user *) optval))
551 			err = -EFAULT;
552 
553 		break;
554 
555 	case BT_POWER:
556 		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
557 		    && sk->sk_type != SOCK_RAW) {
558 			err = -EINVAL;
559 			break;
560 		}
561 
562 		pwr.force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
563 
564 		len = min_t(unsigned int, len, sizeof(pwr));
565 		if (copy_to_user(optval, (char *) &pwr, len))
566 			err = -EFAULT;
567 
568 		break;
569 
570 	case BT_CHANNEL_POLICY:
571 		if (put_user(chan->chan_policy, (u32 __user *) optval))
572 			err = -EFAULT;
573 		break;
574 
575 	case BT_SNDMTU:
576 		if (!bdaddr_type_is_le(chan->src_type)) {
577 			err = -EINVAL;
578 			break;
579 		}
580 
581 		if (sk->sk_state != BT_CONNECTED) {
582 			err = -ENOTCONN;
583 			break;
584 		}
585 
586 		if (put_user(chan->omtu, (u16 __user *) optval))
587 			err = -EFAULT;
588 		break;
589 
590 	case BT_RCVMTU:
591 		if (!bdaddr_type_is_le(chan->src_type)) {
592 			err = -EINVAL;
593 			break;
594 		}
595 
596 		if (put_user(chan->imtu, (u16 __user *) optval))
597 			err = -EFAULT;
598 		break;
599 
600 	default:
601 		err = -ENOPROTOOPT;
602 		break;
603 	}
604 
605 	release_sock(sk);
606 	return err;
607 }
608 
609 static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu)
610 {
611 	switch (chan->scid) {
612 	case L2CAP_CID_ATT:
613 		if (mtu < L2CAP_LE_MIN_MTU)
614 			return false;
615 		break;
616 
617 	default:
618 		if (mtu < L2CAP_DEFAULT_MIN_MTU)
619 			return false;
620 	}
621 
622 	return true;
623 }
624 
625 static int l2cap_sock_setsockopt_old(struct socket *sock, int optname,
626 				     char __user *optval, unsigned int optlen)
627 {
628 	struct sock *sk = sock->sk;
629 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
630 	struct l2cap_options opts;
631 	int len, err = 0;
632 	u32 opt;
633 
634 	BT_DBG("sk %p", sk);
635 
636 	lock_sock(sk);
637 
638 	switch (optname) {
639 	case L2CAP_OPTIONS:
640 		if (bdaddr_type_is_le(chan->src_type)) {
641 			err = -EINVAL;
642 			break;
643 		}
644 
645 		if (sk->sk_state == BT_CONNECTED) {
646 			err = -EINVAL;
647 			break;
648 		}
649 
650 		opts.imtu     = chan->imtu;
651 		opts.omtu     = chan->omtu;
652 		opts.flush_to = chan->flush_to;
653 		opts.mode     = chan->mode;
654 		opts.fcs      = chan->fcs;
655 		opts.max_tx   = chan->max_tx;
656 		opts.txwin_size = chan->tx_win;
657 
658 		len = min_t(unsigned int, sizeof(opts), optlen);
659 		if (copy_from_user((char *) &opts, optval, len)) {
660 			err = -EFAULT;
661 			break;
662 		}
663 
664 		if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) {
665 			err = -EINVAL;
666 			break;
667 		}
668 
669 		if (!l2cap_valid_mtu(chan, opts.imtu)) {
670 			err = -EINVAL;
671 			break;
672 		}
673 
674 		chan->mode = opts.mode;
675 		switch (chan->mode) {
676 		case L2CAP_MODE_LE_FLOWCTL:
677 			break;
678 		case L2CAP_MODE_BASIC:
679 			clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
680 			break;
681 		case L2CAP_MODE_ERTM:
682 		case L2CAP_MODE_STREAMING:
683 			if (!disable_ertm)
684 				break;
685 			/* fall through */
686 		default:
687 			err = -EINVAL;
688 			break;
689 		}
690 
691 		chan->imtu = opts.imtu;
692 		chan->omtu = opts.omtu;
693 		chan->fcs  = opts.fcs;
694 		chan->max_tx = opts.max_tx;
695 		chan->tx_win = opts.txwin_size;
696 		chan->flush_to = opts.flush_to;
697 		break;
698 
699 	case L2CAP_LM:
700 		if (get_user(opt, (u32 __user *) optval)) {
701 			err = -EFAULT;
702 			break;
703 		}
704 
705 		if (opt & L2CAP_LM_FIPS) {
706 			err = -EINVAL;
707 			break;
708 		}
709 
710 		if (opt & L2CAP_LM_AUTH)
711 			chan->sec_level = BT_SECURITY_LOW;
712 		if (opt & L2CAP_LM_ENCRYPT)
713 			chan->sec_level = BT_SECURITY_MEDIUM;
714 		if (opt & L2CAP_LM_SECURE)
715 			chan->sec_level = BT_SECURITY_HIGH;
716 
717 		if (opt & L2CAP_LM_MASTER)
718 			set_bit(FLAG_ROLE_SWITCH, &chan->flags);
719 		else
720 			clear_bit(FLAG_ROLE_SWITCH, &chan->flags);
721 
722 		if (opt & L2CAP_LM_RELIABLE)
723 			set_bit(FLAG_FORCE_RELIABLE, &chan->flags);
724 		else
725 			clear_bit(FLAG_FORCE_RELIABLE, &chan->flags);
726 		break;
727 
728 	default:
729 		err = -ENOPROTOOPT;
730 		break;
731 	}
732 
733 	release_sock(sk);
734 	return err;
735 }
736 
737 static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname,
738 				 char __user *optval, unsigned int optlen)
739 {
740 	struct sock *sk = sock->sk;
741 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
742 	struct bt_security sec;
743 	struct bt_power pwr;
744 	struct l2cap_conn *conn;
745 	int len, err = 0;
746 	u32 opt;
747 
748 	BT_DBG("sk %p", sk);
749 
750 	if (level == SOL_L2CAP)
751 		return l2cap_sock_setsockopt_old(sock, optname, optval, optlen);
752 
753 	if (level != SOL_BLUETOOTH)
754 		return -ENOPROTOOPT;
755 
756 	lock_sock(sk);
757 
758 	switch (optname) {
759 	case BT_SECURITY:
760 		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
761 		    chan->chan_type != L2CAP_CHAN_FIXED &&
762 		    chan->chan_type != L2CAP_CHAN_RAW) {
763 			err = -EINVAL;
764 			break;
765 		}
766 
767 		sec.level = BT_SECURITY_LOW;
768 
769 		len = min_t(unsigned int, sizeof(sec), optlen);
770 		if (copy_from_user((char *) &sec, optval, len)) {
771 			err = -EFAULT;
772 			break;
773 		}
774 
775 		if (sec.level < BT_SECURITY_LOW ||
776 		    sec.level > BT_SECURITY_HIGH) {
777 			err = -EINVAL;
778 			break;
779 		}
780 
781 		chan->sec_level = sec.level;
782 
783 		if (!chan->conn)
784 			break;
785 
786 		conn = chan->conn;
787 
788 		/*change security for LE channels */
789 		if (chan->scid == L2CAP_CID_ATT) {
790 			if (smp_conn_security(conn->hcon, sec.level))
791 				break;
792 			sk->sk_state = BT_CONFIG;
793 			chan->state = BT_CONFIG;
794 
795 		/* or for ACL link */
796 		} else if ((sk->sk_state == BT_CONNECT2 &&
797 			    test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) ||
798 			   sk->sk_state == BT_CONNECTED) {
799 			if (!l2cap_chan_check_security(chan))
800 				set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
801 			else
802 				sk->sk_state_change(sk);
803 		} else {
804 			err = -EINVAL;
805 		}
806 		break;
807 
808 	case BT_DEFER_SETUP:
809 		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
810 			err = -EINVAL;
811 			break;
812 		}
813 
814 		if (get_user(opt, (u32 __user *) optval)) {
815 			err = -EFAULT;
816 			break;
817 		}
818 
819 		if (opt) {
820 			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
821 			set_bit(FLAG_DEFER_SETUP, &chan->flags);
822 		} else {
823 			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
824 			clear_bit(FLAG_DEFER_SETUP, &chan->flags);
825 		}
826 		break;
827 
828 	case BT_FLUSHABLE:
829 		if (get_user(opt, (u32 __user *) optval)) {
830 			err = -EFAULT;
831 			break;
832 		}
833 
834 		if (opt > BT_FLUSHABLE_ON) {
835 			err = -EINVAL;
836 			break;
837 		}
838 
839 		if (opt == BT_FLUSHABLE_OFF) {
840 			conn = chan->conn;
841 			/* proceed further only when we have l2cap_conn and
842 			   No Flush support in the LM */
843 			if (!conn || !lmp_no_flush_capable(conn->hcon->hdev)) {
844 				err = -EINVAL;
845 				break;
846 			}
847 		}
848 
849 		if (opt)
850 			set_bit(FLAG_FLUSHABLE, &chan->flags);
851 		else
852 			clear_bit(FLAG_FLUSHABLE, &chan->flags);
853 		break;
854 
855 	case BT_POWER:
856 		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
857 		    chan->chan_type != L2CAP_CHAN_RAW) {
858 			err = -EINVAL;
859 			break;
860 		}
861 
862 		pwr.force_active = BT_POWER_FORCE_ACTIVE_ON;
863 
864 		len = min_t(unsigned int, sizeof(pwr), optlen);
865 		if (copy_from_user((char *) &pwr, optval, len)) {
866 			err = -EFAULT;
867 			break;
868 		}
869 
870 		if (pwr.force_active)
871 			set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
872 		else
873 			clear_bit(FLAG_FORCE_ACTIVE, &chan->flags);
874 		break;
875 
876 	case BT_CHANNEL_POLICY:
877 		if (get_user(opt, (u32 __user *) optval)) {
878 			err = -EFAULT;
879 			break;
880 		}
881 
882 		if (opt > BT_CHANNEL_POLICY_AMP_PREFERRED) {
883 			err = -EINVAL;
884 			break;
885 		}
886 
887 		if (chan->mode != L2CAP_MODE_ERTM &&
888 		    chan->mode != L2CAP_MODE_STREAMING) {
889 			err = -EOPNOTSUPP;
890 			break;
891 		}
892 
893 		chan->chan_policy = (u8) opt;
894 
895 		if (sk->sk_state == BT_CONNECTED &&
896 		    chan->move_role == L2CAP_MOVE_ROLE_NONE)
897 			l2cap_move_start(chan);
898 
899 		break;
900 
901 	case BT_SNDMTU:
902 		if (!bdaddr_type_is_le(chan->src_type)) {
903 			err = -EINVAL;
904 			break;
905 		}
906 
907 		/* Setting is not supported as it's the remote side that
908 		 * decides this.
909 		 */
910 		err = -EPERM;
911 		break;
912 
913 	case BT_RCVMTU:
914 		if (!bdaddr_type_is_le(chan->src_type)) {
915 			err = -EINVAL;
916 			break;
917 		}
918 
919 		if (sk->sk_state == BT_CONNECTED) {
920 			err = -EISCONN;
921 			break;
922 		}
923 
924 		if (get_user(opt, (u32 __user *) optval)) {
925 			err = -EFAULT;
926 			break;
927 		}
928 
929 		chan->imtu = opt;
930 		break;
931 
932 	default:
933 		err = -ENOPROTOOPT;
934 		break;
935 	}
936 
937 	release_sock(sk);
938 	return err;
939 }
940 
941 static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
942 			      struct msghdr *msg, size_t len)
943 {
944 	struct sock *sk = sock->sk;
945 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
946 	int err;
947 
948 	BT_DBG("sock %p, sk %p", sock, sk);
949 
950 	err = sock_error(sk);
951 	if (err)
952 		return err;
953 
954 	if (msg->msg_flags & MSG_OOB)
955 		return -EOPNOTSUPP;
956 
957 	if (sk->sk_state != BT_CONNECTED)
958 		return -ENOTCONN;
959 
960 	lock_sock(sk);
961 	err = bt_sock_wait_ready(sk, msg->msg_flags);
962 	release_sock(sk);
963 	if (err)
964 		return err;
965 
966 	l2cap_chan_lock(chan);
967 	err = l2cap_chan_send(chan, msg, len, sk->sk_priority);
968 	l2cap_chan_unlock(chan);
969 
970 	return err;
971 }
972 
973 static int l2cap_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
974 			      struct msghdr *msg, size_t len, int flags)
975 {
976 	struct sock *sk = sock->sk;
977 	struct l2cap_pinfo *pi = l2cap_pi(sk);
978 	int err;
979 
980 	lock_sock(sk);
981 
982 	if (sk->sk_state == BT_CONNECT2 && test_bit(BT_SK_DEFER_SETUP,
983 						    &bt_sk(sk)->flags)) {
984 		if (bdaddr_type_is_le(pi->chan->src_type)) {
985 			sk->sk_state = BT_CONNECTED;
986 			pi->chan->state = BT_CONNECTED;
987 			__l2cap_le_connect_rsp_defer(pi->chan);
988 		} else {
989 			sk->sk_state = BT_CONFIG;
990 			pi->chan->state = BT_CONFIG;
991 			__l2cap_connect_rsp_defer(pi->chan);
992 		}
993 
994 		err = 0;
995 		goto done;
996 	}
997 
998 	release_sock(sk);
999 
1000 	if (sock->type == SOCK_STREAM)
1001 		err = bt_sock_stream_recvmsg(iocb, sock, msg, len, flags);
1002 	else
1003 		err = bt_sock_recvmsg(iocb, sock, msg, len, flags);
1004 
1005 	if (pi->chan->mode != L2CAP_MODE_ERTM)
1006 		return err;
1007 
1008 	/* Attempt to put pending rx data in the socket buffer */
1009 
1010 	lock_sock(sk);
1011 
1012 	if (!test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state))
1013 		goto done;
1014 
1015 	if (pi->rx_busy_skb) {
1016 		if (!sock_queue_rcv_skb(sk, pi->rx_busy_skb))
1017 			pi->rx_busy_skb = NULL;
1018 		else
1019 			goto done;
1020 	}
1021 
1022 	/* Restore data flow when half of the receive buffer is
1023 	 * available.  This avoids resending large numbers of
1024 	 * frames.
1025 	 */
1026 	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1)
1027 		l2cap_chan_busy(pi->chan, 0);
1028 
1029 done:
1030 	release_sock(sk);
1031 	return err;
1032 }
1033 
1034 /* Kill socket (only if zapped and orphan)
1035  * Must be called on unlocked socket.
1036  */
1037 static void l2cap_sock_kill(struct sock *sk)
1038 {
1039 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
1040 		return;
1041 
1042 	BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state));
1043 
1044 	/* Kill poor orphan */
1045 
1046 	l2cap_chan_put(l2cap_pi(sk)->chan);
1047 	sock_set_flag(sk, SOCK_DEAD);
1048 	sock_put(sk);
1049 }
1050 
1051 static int __l2cap_wait_ack(struct sock *sk)
1052 {
1053 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1054 	DECLARE_WAITQUEUE(wait, current);
1055 	int err = 0;
1056 	int timeo = HZ/5;
1057 
1058 	add_wait_queue(sk_sleep(sk), &wait);
1059 	set_current_state(TASK_INTERRUPTIBLE);
1060 	while (chan->unacked_frames > 0 && chan->conn) {
1061 		if (!timeo)
1062 			timeo = HZ/5;
1063 
1064 		if (signal_pending(current)) {
1065 			err = sock_intr_errno(timeo);
1066 			break;
1067 		}
1068 
1069 		release_sock(sk);
1070 		timeo = schedule_timeout(timeo);
1071 		lock_sock(sk);
1072 		set_current_state(TASK_INTERRUPTIBLE);
1073 
1074 		err = sock_error(sk);
1075 		if (err)
1076 			break;
1077 	}
1078 	set_current_state(TASK_RUNNING);
1079 	remove_wait_queue(sk_sleep(sk), &wait);
1080 	return err;
1081 }
1082 
1083 static int l2cap_sock_shutdown(struct socket *sock, int how)
1084 {
1085 	struct sock *sk = sock->sk;
1086 	struct l2cap_chan *chan;
1087 	struct l2cap_conn *conn;
1088 	int err = 0;
1089 
1090 	BT_DBG("sock %p, sk %p", sock, sk);
1091 
1092 	if (!sk)
1093 		return 0;
1094 
1095 	chan = l2cap_pi(sk)->chan;
1096 	conn = chan->conn;
1097 
1098 	if (conn)
1099 		mutex_lock(&conn->chan_lock);
1100 
1101 	l2cap_chan_lock(chan);
1102 	lock_sock(sk);
1103 
1104 	if (!sk->sk_shutdown) {
1105 		if (chan->mode == L2CAP_MODE_ERTM)
1106 			err = __l2cap_wait_ack(sk);
1107 
1108 		sk->sk_shutdown = SHUTDOWN_MASK;
1109 
1110 		release_sock(sk);
1111 		l2cap_chan_close(chan, 0);
1112 		lock_sock(sk);
1113 
1114 		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
1115 			err = bt_sock_wait_state(sk, BT_CLOSED,
1116 						 sk->sk_lingertime);
1117 	}
1118 
1119 	if (!err && sk->sk_err)
1120 		err = -sk->sk_err;
1121 
1122 	release_sock(sk);
1123 	l2cap_chan_unlock(chan);
1124 
1125 	if (conn)
1126 		mutex_unlock(&conn->chan_lock);
1127 
1128 	return err;
1129 }
1130 
1131 static int l2cap_sock_release(struct socket *sock)
1132 {
1133 	struct sock *sk = sock->sk;
1134 	int err;
1135 
1136 	BT_DBG("sock %p, sk %p", sock, sk);
1137 
1138 	if (!sk)
1139 		return 0;
1140 
1141 	bt_sock_unlink(&l2cap_sk_list, sk);
1142 
1143 	err = l2cap_sock_shutdown(sock, 2);
1144 
1145 	sock_orphan(sk);
1146 	l2cap_sock_kill(sk);
1147 	return err;
1148 }
1149 
1150 static void l2cap_sock_cleanup_listen(struct sock *parent)
1151 {
1152 	struct sock *sk;
1153 
1154 	BT_DBG("parent %p", parent);
1155 
1156 	/* Close not yet accepted channels */
1157 	while ((sk = bt_accept_dequeue(parent, NULL))) {
1158 		struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1159 
1160 		l2cap_chan_lock(chan);
1161 		__clear_chan_timer(chan);
1162 		l2cap_chan_close(chan, ECONNRESET);
1163 		l2cap_chan_unlock(chan);
1164 
1165 		l2cap_sock_kill(sk);
1166 	}
1167 }
1168 
1169 static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
1170 {
1171 	struct sock *sk, *parent = chan->data;
1172 
1173 	lock_sock(parent);
1174 
1175 	/* Check for backlog size */
1176 	if (sk_acceptq_is_full(parent)) {
1177 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
1178 		release_sock(parent);
1179 		return NULL;
1180 	}
1181 
1182 	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP,
1183 			      GFP_ATOMIC);
1184 	if (!sk) {
1185 		release_sock(parent);
1186 		return NULL;
1187         }
1188 
1189 	bt_sock_reclassify_lock(sk, BTPROTO_L2CAP);
1190 
1191 	l2cap_sock_init(sk, parent);
1192 
1193 	bt_accept_enqueue(parent, sk);
1194 
1195 	release_sock(parent);
1196 
1197 	return l2cap_pi(sk)->chan;
1198 }
1199 
1200 static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
1201 {
1202 	struct sock *sk = chan->data;
1203 	int err;
1204 
1205 	lock_sock(sk);
1206 
1207 	if (l2cap_pi(sk)->rx_busy_skb) {
1208 		err = -ENOMEM;
1209 		goto done;
1210 	}
1211 
1212 	err = sock_queue_rcv_skb(sk, skb);
1213 
1214 	/* For ERTM, handle one skb that doesn't fit into the recv
1215 	 * buffer.  This is important to do because the data frames
1216 	 * have already been acked, so the skb cannot be discarded.
1217 	 *
1218 	 * Notify the l2cap core that the buffer is full, so the
1219 	 * LOCAL_BUSY state is entered and no more frames are
1220 	 * acked and reassembled until there is buffer space
1221 	 * available.
1222 	 */
1223 	if (err < 0 && chan->mode == L2CAP_MODE_ERTM) {
1224 		l2cap_pi(sk)->rx_busy_skb = skb;
1225 		l2cap_chan_busy(chan, 1);
1226 		err = 0;
1227 	}
1228 
1229 done:
1230 	release_sock(sk);
1231 
1232 	return err;
1233 }
1234 
1235 static void l2cap_sock_close_cb(struct l2cap_chan *chan)
1236 {
1237 	struct sock *sk = chan->data;
1238 
1239 	l2cap_sock_kill(sk);
1240 }
1241 
1242 static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err)
1243 {
1244 	struct sock *sk = chan->data;
1245 	struct sock *parent;
1246 
1247 	lock_sock(sk);
1248 
1249 	parent = bt_sk(sk)->parent;
1250 
1251 	sock_set_flag(sk, SOCK_ZAPPED);
1252 
1253 	switch (chan->state) {
1254 	case BT_OPEN:
1255 	case BT_BOUND:
1256 	case BT_CLOSED:
1257 		break;
1258 	case BT_LISTEN:
1259 		l2cap_sock_cleanup_listen(sk);
1260 		sk->sk_state = BT_CLOSED;
1261 		chan->state = BT_CLOSED;
1262 
1263 		break;
1264 	default:
1265 		sk->sk_state = BT_CLOSED;
1266 		chan->state = BT_CLOSED;
1267 
1268 		sk->sk_err = err;
1269 
1270 		if (parent) {
1271 			bt_accept_unlink(sk);
1272 			parent->sk_data_ready(parent);
1273 		} else {
1274 			sk->sk_state_change(sk);
1275 		}
1276 
1277 		break;
1278 	}
1279 
1280 	release_sock(sk);
1281 }
1282 
1283 static void l2cap_sock_state_change_cb(struct l2cap_chan *chan, int state,
1284 				       int err)
1285 {
1286 	struct sock *sk = chan->data;
1287 
1288 	sk->sk_state = state;
1289 
1290 	if (err)
1291 		sk->sk_err = err;
1292 }
1293 
1294 static struct sk_buff *l2cap_sock_alloc_skb_cb(struct l2cap_chan *chan,
1295 					       unsigned long len, int nb)
1296 {
1297 	struct sock *sk = chan->data;
1298 	struct sk_buff *skb;
1299 	int err;
1300 
1301 	l2cap_chan_unlock(chan);
1302 	skb = bt_skb_send_alloc(sk, len, nb, &err);
1303 	l2cap_chan_lock(chan);
1304 
1305 	if (!skb)
1306 		return ERR_PTR(err);
1307 
1308 	bt_cb(skb)->chan = chan;
1309 
1310 	return skb;
1311 }
1312 
1313 static void l2cap_sock_ready_cb(struct l2cap_chan *chan)
1314 {
1315 	struct sock *sk = chan->data;
1316 	struct sock *parent;
1317 
1318 	lock_sock(sk);
1319 
1320 	parent = bt_sk(sk)->parent;
1321 
1322 	BT_DBG("sk %p, parent %p", sk, parent);
1323 
1324 	sk->sk_state = BT_CONNECTED;
1325 	sk->sk_state_change(sk);
1326 
1327 	if (parent)
1328 		parent->sk_data_ready(parent);
1329 
1330 	release_sock(sk);
1331 }
1332 
1333 static void l2cap_sock_defer_cb(struct l2cap_chan *chan)
1334 {
1335 	struct sock *parent, *sk = chan->data;
1336 
1337 	lock_sock(sk);
1338 
1339 	parent = bt_sk(sk)->parent;
1340 	if (parent)
1341 		parent->sk_data_ready(parent);
1342 
1343 	release_sock(sk);
1344 }
1345 
1346 static void l2cap_sock_resume_cb(struct l2cap_chan *chan)
1347 {
1348 	struct sock *sk = chan->data;
1349 
1350 	clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
1351 	sk->sk_state_change(sk);
1352 }
1353 
1354 static void l2cap_sock_set_shutdown_cb(struct l2cap_chan *chan)
1355 {
1356 	struct sock *sk = chan->data;
1357 
1358 	lock_sock(sk);
1359 	sk->sk_shutdown = SHUTDOWN_MASK;
1360 	release_sock(sk);
1361 }
1362 
1363 static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan)
1364 {
1365 	struct sock *sk = chan->data;
1366 
1367 	return sk->sk_sndtimeo;
1368 }
1369 
1370 static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
1371 {
1372 	struct sock *sk = chan->data;
1373 
1374 	set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
1375 	sk->sk_state_change(sk);
1376 }
1377 
1378 static struct l2cap_ops l2cap_chan_ops = {
1379 	.name		= "L2CAP Socket Interface",
1380 	.new_connection	= l2cap_sock_new_connection_cb,
1381 	.recv		= l2cap_sock_recv_cb,
1382 	.close		= l2cap_sock_close_cb,
1383 	.teardown	= l2cap_sock_teardown_cb,
1384 	.state_change	= l2cap_sock_state_change_cb,
1385 	.ready		= l2cap_sock_ready_cb,
1386 	.defer		= l2cap_sock_defer_cb,
1387 	.resume		= l2cap_sock_resume_cb,
1388 	.suspend	= l2cap_sock_suspend_cb,
1389 	.set_shutdown	= l2cap_sock_set_shutdown_cb,
1390 	.get_sndtimeo	= l2cap_sock_get_sndtimeo_cb,
1391 	.alloc_skb	= l2cap_sock_alloc_skb_cb,
1392 };
1393 
1394 static void l2cap_sock_destruct(struct sock *sk)
1395 {
1396 	BT_DBG("sk %p", sk);
1397 
1398 	if (l2cap_pi(sk)->chan)
1399 		l2cap_chan_put(l2cap_pi(sk)->chan);
1400 
1401 	if (l2cap_pi(sk)->rx_busy_skb) {
1402 		kfree_skb(l2cap_pi(sk)->rx_busy_skb);
1403 		l2cap_pi(sk)->rx_busy_skb = NULL;
1404 	}
1405 
1406 	skb_queue_purge(&sk->sk_receive_queue);
1407 	skb_queue_purge(&sk->sk_write_queue);
1408 }
1409 
1410 static void l2cap_skb_msg_name(struct sk_buff *skb, void *msg_name,
1411 			       int *msg_namelen)
1412 {
1413 	DECLARE_SOCKADDR(struct sockaddr_l2 *, la, msg_name);
1414 
1415 	memset(la, 0, sizeof(struct sockaddr_l2));
1416 	la->l2_family = AF_BLUETOOTH;
1417 	la->l2_psm = bt_cb(skb)->psm;
1418 	bacpy(&la->l2_bdaddr, &bt_cb(skb)->bdaddr);
1419 
1420 	*msg_namelen = sizeof(struct sockaddr_l2);
1421 }
1422 
1423 static void l2cap_sock_init(struct sock *sk, struct sock *parent)
1424 {
1425 	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1426 
1427 	BT_DBG("sk %p", sk);
1428 
1429 	if (parent) {
1430 		struct l2cap_chan *pchan = l2cap_pi(parent)->chan;
1431 
1432 		sk->sk_type = parent->sk_type;
1433 		bt_sk(sk)->flags = bt_sk(parent)->flags;
1434 
1435 		chan->chan_type = pchan->chan_type;
1436 		chan->imtu = pchan->imtu;
1437 		chan->omtu = pchan->omtu;
1438 		chan->conf_state = pchan->conf_state;
1439 		chan->mode = pchan->mode;
1440 		chan->fcs  = pchan->fcs;
1441 		chan->max_tx = pchan->max_tx;
1442 		chan->tx_win = pchan->tx_win;
1443 		chan->tx_win_max = pchan->tx_win_max;
1444 		chan->sec_level = pchan->sec_level;
1445 		chan->flags = pchan->flags;
1446 		chan->tx_credits = pchan->tx_credits;
1447 		chan->rx_credits = pchan->rx_credits;
1448 
1449 		if (chan->chan_type == L2CAP_CHAN_FIXED) {
1450 			chan->scid = pchan->scid;
1451 			chan->dcid = pchan->scid;
1452 		}
1453 
1454 		security_sk_clone(parent, sk);
1455 	} else {
1456 		switch (sk->sk_type) {
1457 		case SOCK_RAW:
1458 			chan->chan_type = L2CAP_CHAN_RAW;
1459 			break;
1460 		case SOCK_DGRAM:
1461 			chan->chan_type = L2CAP_CHAN_CONN_LESS;
1462 			bt_sk(sk)->skb_msg_name = l2cap_skb_msg_name;
1463 			break;
1464 		case SOCK_SEQPACKET:
1465 		case SOCK_STREAM:
1466 			chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
1467 			break;
1468 		}
1469 
1470 		chan->imtu = L2CAP_DEFAULT_MTU;
1471 		chan->omtu = 0;
1472 		if (!disable_ertm && sk->sk_type == SOCK_STREAM) {
1473 			chan->mode = L2CAP_MODE_ERTM;
1474 			set_bit(CONF_STATE2_DEVICE, &chan->conf_state);
1475 		} else {
1476 			chan->mode = L2CAP_MODE_BASIC;
1477 		}
1478 
1479 		l2cap_chan_set_defaults(chan);
1480 	}
1481 
1482 	/* Default config options */
1483 	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
1484 
1485 	chan->data = sk;
1486 	chan->ops = &l2cap_chan_ops;
1487 }
1488 
1489 static struct proto l2cap_proto = {
1490 	.name		= "L2CAP",
1491 	.owner		= THIS_MODULE,
1492 	.obj_size	= sizeof(struct l2cap_pinfo)
1493 };
1494 
1495 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
1496 				     int proto, gfp_t prio)
1497 {
1498 	struct sock *sk;
1499 	struct l2cap_chan *chan;
1500 
1501 	sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto);
1502 	if (!sk)
1503 		return NULL;
1504 
1505 	sock_init_data(sock, sk);
1506 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
1507 
1508 	sk->sk_destruct = l2cap_sock_destruct;
1509 	sk->sk_sndtimeo = L2CAP_CONN_TIMEOUT;
1510 
1511 	sock_reset_flag(sk, SOCK_ZAPPED);
1512 
1513 	sk->sk_protocol = proto;
1514 	sk->sk_state = BT_OPEN;
1515 
1516 	chan = l2cap_chan_create();
1517 	if (!chan) {
1518 		sk_free(sk);
1519 		return NULL;
1520 	}
1521 
1522 	l2cap_chan_hold(chan);
1523 
1524 	l2cap_pi(sk)->chan = chan;
1525 
1526 	return sk;
1527 }
1528 
1529 static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
1530 			     int kern)
1531 {
1532 	struct sock *sk;
1533 
1534 	BT_DBG("sock %p", sock);
1535 
1536 	sock->state = SS_UNCONNECTED;
1537 
1538 	if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM &&
1539 	    sock->type != SOCK_DGRAM && sock->type != SOCK_RAW)
1540 		return -ESOCKTNOSUPPORT;
1541 
1542 	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
1543 		return -EPERM;
1544 
1545 	sock->ops = &l2cap_sock_ops;
1546 
1547 	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC);
1548 	if (!sk)
1549 		return -ENOMEM;
1550 
1551 	l2cap_sock_init(sk, NULL);
1552 	bt_sock_link(&l2cap_sk_list, sk);
1553 	return 0;
1554 }
1555 
1556 static const struct proto_ops l2cap_sock_ops = {
1557 	.family		= PF_BLUETOOTH,
1558 	.owner		= THIS_MODULE,
1559 	.release	= l2cap_sock_release,
1560 	.bind		= l2cap_sock_bind,
1561 	.connect	= l2cap_sock_connect,
1562 	.listen		= l2cap_sock_listen,
1563 	.accept		= l2cap_sock_accept,
1564 	.getname	= l2cap_sock_getname,
1565 	.sendmsg	= l2cap_sock_sendmsg,
1566 	.recvmsg	= l2cap_sock_recvmsg,
1567 	.poll		= bt_sock_poll,
1568 	.ioctl		= bt_sock_ioctl,
1569 	.mmap		= sock_no_mmap,
1570 	.socketpair	= sock_no_socketpair,
1571 	.shutdown	= l2cap_sock_shutdown,
1572 	.setsockopt	= l2cap_sock_setsockopt,
1573 	.getsockopt	= l2cap_sock_getsockopt
1574 };
1575 
1576 static const struct net_proto_family l2cap_sock_family_ops = {
1577 	.family	= PF_BLUETOOTH,
1578 	.owner	= THIS_MODULE,
1579 	.create	= l2cap_sock_create,
1580 };
1581 
1582 int __init l2cap_init_sockets(void)
1583 {
1584 	int err;
1585 
1586 	err = proto_register(&l2cap_proto, 0);
1587 	if (err < 0)
1588 		return err;
1589 
1590 	err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops);
1591 	if (err < 0) {
1592 		BT_ERR("L2CAP socket registration failed");
1593 		goto error;
1594 	}
1595 
1596 	err = bt_procfs_init(&init_net, "l2cap", &l2cap_sk_list,
1597 			     NULL);
1598 	if (err < 0) {
1599 		BT_ERR("Failed to create L2CAP proc file");
1600 		bt_sock_unregister(BTPROTO_L2CAP);
1601 		goto error;
1602 	}
1603 
1604 	BT_INFO("L2CAP socket layer initialized");
1605 
1606 	return 0;
1607 
1608 error:
1609 	proto_unregister(&l2cap_proto);
1610 	return err;
1611 }
1612 
1613 void l2cap_cleanup_sockets(void)
1614 {
1615 	bt_procfs_cleanup(&init_net, "l2cap");
1616 	bt_sock_unregister(BTPROTO_L2CAP);
1617 	proto_unregister(&l2cap_proto);
1618 }
1619