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v6.8
   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#include <linux/filter.h>
  33#include <linux/sched/signal.h>
  34
  35#include <net/bluetooth/bluetooth.h>
  36#include <net/bluetooth/hci_core.h>
  37#include <net/bluetooth/l2cap.h>
  38
  39#include "smp.h"
  40
  41static struct bt_sock_list l2cap_sk_list = {
  42	.lock = __RW_LOCK_UNLOCKED(l2cap_sk_list.lock)
  43};
  44
  45static const struct proto_ops l2cap_sock_ops;
  46static void l2cap_sock_init(struct sock *sk, struct sock *parent);
  47static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
  48				     int proto, gfp_t prio, int kern);
  49static void l2cap_sock_cleanup_listen(struct sock *parent);
  50
  51bool l2cap_is_socket(struct socket *sock)
  52{
  53	return sock && sock->ops == &l2cap_sock_ops;
  54}
  55EXPORT_SYMBOL(l2cap_is_socket);
  56
  57static int l2cap_validate_bredr_psm(u16 psm)
  58{
  59	/* PSM must be odd and lsb of upper byte must be 0 */
  60	if ((psm & 0x0101) != 0x0001)
  61		return -EINVAL;
  62
  63	/* Restrict usage of well-known PSMs */
  64	if (psm < L2CAP_PSM_DYN_START && !capable(CAP_NET_BIND_SERVICE))
  65		return -EACCES;
  66
  67	return 0;
  68}
  69
  70static int l2cap_validate_le_psm(u16 psm)
  71{
  72	/* Valid LE_PSM ranges are defined only until 0x00ff */
  73	if (psm > L2CAP_PSM_LE_DYN_END)
  74		return -EINVAL;
  75
  76	/* Restrict fixed, SIG assigned PSM values to CAP_NET_BIND_SERVICE */
  77	if (psm < L2CAP_PSM_LE_DYN_START && !capable(CAP_NET_BIND_SERVICE))
  78		return -EACCES;
  79
  80	return 0;
  81}
  82
  83static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
  84{
  85	struct sock *sk = sock->sk;
  86	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
  87	struct sockaddr_l2 la;
  88	int len, err = 0;
  89
  90	BT_DBG("sk %p", sk);
  91
  92	if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
  93	    addr->sa_family != AF_BLUETOOTH)
  94		return -EINVAL;
  95
  96	memset(&la, 0, sizeof(la));
  97	len = min_t(unsigned int, sizeof(la), alen);
  98	memcpy(&la, addr, len);
  99
 100	if (la.l2_cid && la.l2_psm)
 101		return -EINVAL;
 102
 103	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
 104		return -EINVAL;
 105
 106	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
 107		/* We only allow ATT user space socket */
 108		if (la.l2_cid &&
 109		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
 110			return -EINVAL;
 111	}
 112
 113	lock_sock(sk);
 114
 115	if (sk->sk_state != BT_OPEN) {
 116		err = -EBADFD;
 117		goto done;
 118	}
 119
 120	if (la.l2_psm) {
 121		__u16 psm = __le16_to_cpu(la.l2_psm);
 122
 123		if (la.l2_bdaddr_type == BDADDR_BREDR)
 124			err = l2cap_validate_bredr_psm(psm);
 125		else
 126			err = l2cap_validate_le_psm(psm);
 127
 128		if (err)
 129			goto done;
 130	}
 131
 132	bacpy(&chan->src, &la.l2_bdaddr);
 133	chan->src_type = la.l2_bdaddr_type;
 134
 135	if (la.l2_cid)
 136		err = l2cap_add_scid(chan, __le16_to_cpu(la.l2_cid));
 137	else
 138		err = l2cap_add_psm(chan, &la.l2_bdaddr, la.l2_psm);
 139
 140	if (err < 0)
 141		goto done;
 142
 143	switch (chan->chan_type) {
 144	case L2CAP_CHAN_CONN_LESS:
 145		if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_3DSP)
 146			chan->sec_level = BT_SECURITY_SDP;
 147		break;
 148	case L2CAP_CHAN_CONN_ORIENTED:
 149		if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_SDP ||
 150		    __le16_to_cpu(la.l2_psm) == L2CAP_PSM_RFCOMM)
 151			chan->sec_level = BT_SECURITY_SDP;
 152		break;
 153	case L2CAP_CHAN_RAW:
 154		chan->sec_level = BT_SECURITY_SDP;
 155		break;
 156	case L2CAP_CHAN_FIXED:
 157		/* Fixed channels default to the L2CAP core not holding a
 158		 * hci_conn reference for them. For fixed channels mapping to
 159		 * L2CAP sockets we do want to hold a reference so set the
 160		 * appropriate flag to request it.
 161		 */
 162		set_bit(FLAG_HOLD_HCI_CONN, &chan->flags);
 163		break;
 164	}
 165
 166	/* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and
 167	 * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set.
 168	 */
 169	if (chan->psm && bdaddr_type_is_le(chan->src_type) &&
 170	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 171		chan->mode = L2CAP_MODE_LE_FLOWCTL;
 172
 173	chan->state = BT_BOUND;
 174	sk->sk_state = BT_BOUND;
 175
 176done:
 177	release_sock(sk);
 178	return err;
 179}
 180
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 181static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr,
 182			      int alen, int flags)
 183{
 184	struct sock *sk = sock->sk;
 185	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 186	struct sockaddr_l2 la;
 187	int len, err = 0;
 188	bool zapped;
 189
 190	BT_DBG("sk %p", sk);
 191
 192	lock_sock(sk);
 193	zapped = sock_flag(sk, SOCK_ZAPPED);
 194	release_sock(sk);
 195
 196	if (zapped)
 197		return -EINVAL;
 198
 199	if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
 200	    addr->sa_family != AF_BLUETOOTH)
 201		return -EINVAL;
 202
 203	memset(&la, 0, sizeof(la));
 204	len = min_t(unsigned int, sizeof(la), alen);
 205	memcpy(&la, addr, len);
 206
 207	if (la.l2_cid && la.l2_psm)
 208		return -EINVAL;
 209
 210	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
 211		return -EINVAL;
 212
 213	/* Check that the socket wasn't bound to something that
 214	 * conflicts with the address given to connect(). If chan->src
 215	 * is BDADDR_ANY it means bind() was never used, in which case
 216	 * chan->src_type and la.l2_bdaddr_type do not need to match.
 217	 */
 218	if (chan->src_type == BDADDR_BREDR && bacmp(&chan->src, BDADDR_ANY) &&
 219	    bdaddr_type_is_le(la.l2_bdaddr_type)) {
 220		/* Old user space versions will try to incorrectly bind
 221		 * the ATT socket using BDADDR_BREDR. We need to accept
 222		 * this and fix up the source address type only when
 223		 * both the source CID and destination CID indicate
 224		 * ATT. Anything else is an invalid combination.
 225		 */
 226		if (chan->scid != L2CAP_CID_ATT ||
 227		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
 228			return -EINVAL;
 229
 230		/* We don't have the hdev available here to make a
 231		 * better decision on random vs public, but since all
 232		 * user space versions that exhibit this issue anyway do
 233		 * not support random local addresses assuming public
 234		 * here is good enough.
 235		 */
 236		chan->src_type = BDADDR_LE_PUBLIC;
 237	}
 238
 239	if (chan->src_type != BDADDR_BREDR && la.l2_bdaddr_type == BDADDR_BREDR)
 240		return -EINVAL;
 241
 242	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
 243		/* We only allow ATT user space socket */
 244		if (la.l2_cid &&
 245		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
 246			return -EINVAL;
 247	}
 248
 249	/* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and
 250	 * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set.
 251	 */
 252	if (chan->psm && bdaddr_type_is_le(chan->src_type) &&
 253	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 254		chan->mode = L2CAP_MODE_LE_FLOWCTL;
 255
 
 
 256	err = l2cap_chan_connect(chan, la.l2_psm, __le16_to_cpu(la.l2_cid),
 257				 &la.l2_bdaddr, la.l2_bdaddr_type);
 258	if (err)
 259		return err;
 260
 261	lock_sock(sk);
 262
 263	err = bt_sock_wait_state(sk, BT_CONNECTED,
 264				 sock_sndtimeo(sk, flags & O_NONBLOCK));
 265
 266	release_sock(sk);
 267
 268	return err;
 269}
 270
 271static int l2cap_sock_listen(struct socket *sock, int backlog)
 272{
 273	struct sock *sk = sock->sk;
 274	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 275	int err = 0;
 276
 277	BT_DBG("sk %p backlog %d", sk, backlog);
 278
 279	lock_sock(sk);
 280
 281	if (sk->sk_state != BT_BOUND) {
 282		err = -EBADFD;
 283		goto done;
 284	}
 285
 286	if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM) {
 287		err = -EINVAL;
 288		goto done;
 289	}
 290
 291	switch (chan->mode) {
 292	case L2CAP_MODE_BASIC:
 293	case L2CAP_MODE_LE_FLOWCTL:
 294		break;
 295	case L2CAP_MODE_EXT_FLOWCTL:
 296		if (!enable_ecred) {
 297			err = -EOPNOTSUPP;
 298			goto done;
 299		}
 300		break;
 301	case L2CAP_MODE_ERTM:
 302	case L2CAP_MODE_STREAMING:
 303		if (!disable_ertm)
 304			break;
 305		fallthrough;
 306	default:
 307		err = -EOPNOTSUPP;
 308		goto done;
 309	}
 310
 
 
 311	sk->sk_max_ack_backlog = backlog;
 312	sk->sk_ack_backlog = 0;
 313
 314	/* Listening channels need to use nested locking in order not to
 315	 * cause lockdep warnings when the created child channels end up
 316	 * being locked in the same thread as the parent channel.
 317	 */
 318	atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
 319
 320	chan->state = BT_LISTEN;
 321	sk->sk_state = BT_LISTEN;
 322
 323done:
 324	release_sock(sk);
 325	return err;
 326}
 327
 328static int l2cap_sock_accept(struct socket *sock, struct socket *newsock,
 329			     int flags, bool kern)
 330{
 331	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 332	struct sock *sk = sock->sk, *nsk;
 333	long timeo;
 334	int err = 0;
 335
 336	lock_sock_nested(sk, L2CAP_NESTING_PARENT);
 337
 338	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 339
 340	BT_DBG("sk %p timeo %ld", sk, timeo);
 341
 342	/* Wait for an incoming connection. (wake-one). */
 343	add_wait_queue_exclusive(sk_sleep(sk), &wait);
 344	while (1) {
 345		if (sk->sk_state != BT_LISTEN) {
 346			err = -EBADFD;
 347			break;
 348		}
 349
 350		nsk = bt_accept_dequeue(sk, newsock);
 351		if (nsk)
 352			break;
 353
 354		if (!timeo) {
 355			err = -EAGAIN;
 356			break;
 357		}
 358
 359		if (signal_pending(current)) {
 360			err = sock_intr_errno(timeo);
 361			break;
 362		}
 363
 364		release_sock(sk);
 365
 366		timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
 367
 368		lock_sock_nested(sk, L2CAP_NESTING_PARENT);
 369	}
 370	remove_wait_queue(sk_sleep(sk), &wait);
 371
 372	if (err)
 373		goto done;
 374
 375	newsock->state = SS_CONNECTED;
 376
 377	BT_DBG("new socket %p", nsk);
 378
 379done:
 380	release_sock(sk);
 381	return err;
 382}
 383
 384static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr,
 385			      int peer)
 386{
 387	struct sockaddr_l2 *la = (struct sockaddr_l2 *) addr;
 388	struct sock *sk = sock->sk;
 389	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 390
 391	BT_DBG("sock %p, sk %p", sock, sk);
 392
 393	if (peer && sk->sk_state != BT_CONNECTED &&
 394	    sk->sk_state != BT_CONNECT && sk->sk_state != BT_CONNECT2 &&
 395	    sk->sk_state != BT_CONFIG)
 396		return -ENOTCONN;
 397
 398	memset(la, 0, sizeof(struct sockaddr_l2));
 399	addr->sa_family = AF_BLUETOOTH;
 400
 401	la->l2_psm = chan->psm;
 402
 403	if (peer) {
 404		bacpy(&la->l2_bdaddr, &chan->dst);
 405		la->l2_cid = cpu_to_le16(chan->dcid);
 406		la->l2_bdaddr_type = chan->dst_type;
 407	} else {
 408		bacpy(&la->l2_bdaddr, &chan->src);
 409		la->l2_cid = cpu_to_le16(chan->scid);
 410		la->l2_bdaddr_type = chan->src_type;
 411	}
 412
 413	return sizeof(struct sockaddr_l2);
 414}
 415
 416static int l2cap_get_mode(struct l2cap_chan *chan)
 417{
 418	switch (chan->mode) {
 419	case L2CAP_MODE_BASIC:
 420		return BT_MODE_BASIC;
 421	case L2CAP_MODE_ERTM:
 422		return BT_MODE_ERTM;
 423	case L2CAP_MODE_STREAMING:
 424		return BT_MODE_STREAMING;
 425	case L2CAP_MODE_LE_FLOWCTL:
 426		return BT_MODE_LE_FLOWCTL;
 427	case L2CAP_MODE_EXT_FLOWCTL:
 428		return BT_MODE_EXT_FLOWCTL;
 429	}
 430
 431	return -EINVAL;
 432}
 433
 434static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
 435				     char __user *optval, int __user *optlen)
 436{
 437	struct sock *sk = sock->sk;
 438	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 439	struct l2cap_options opts;
 440	struct l2cap_conninfo cinfo;
 441	int len, err = 0;
 442	u32 opt;
 443
 444	BT_DBG("sk %p", sk);
 445
 446	if (get_user(len, optlen))
 447		return -EFAULT;
 448
 449	lock_sock(sk);
 450
 451	switch (optname) {
 452	case L2CAP_OPTIONS:
 453		/* LE sockets should use BT_SNDMTU/BT_RCVMTU, but since
 454		 * legacy ATT code depends on getsockopt for
 455		 * L2CAP_OPTIONS we need to let this pass.
 456		 */
 457		if (bdaddr_type_is_le(chan->src_type) &&
 458		    chan->scid != L2CAP_CID_ATT) {
 459			err = -EINVAL;
 460			break;
 461		}
 462
 463		/* Only BR/EDR modes are supported here */
 464		switch (chan->mode) {
 465		case L2CAP_MODE_BASIC:
 466		case L2CAP_MODE_ERTM:
 467		case L2CAP_MODE_STREAMING:
 468			break;
 469		default:
 470			err = -EINVAL;
 471			break;
 472		}
 473
 474		if (err < 0)
 475			break;
 476
 477		memset(&opts, 0, sizeof(opts));
 478		opts.imtu     = chan->imtu;
 479		opts.omtu     = chan->omtu;
 480		opts.flush_to = chan->flush_to;
 481		opts.mode     = chan->mode;
 482		opts.fcs      = chan->fcs;
 483		opts.max_tx   = chan->max_tx;
 484		opts.txwin_size = chan->tx_win;
 485
 486		BT_DBG("mode 0x%2.2x", chan->mode);
 487
 488		len = min_t(unsigned int, len, sizeof(opts));
 489		if (copy_to_user(optval, (char *) &opts, len))
 490			err = -EFAULT;
 491
 492		break;
 493
 494	case L2CAP_LM:
 495		switch (chan->sec_level) {
 496		case BT_SECURITY_LOW:
 497			opt = L2CAP_LM_AUTH;
 498			break;
 499		case BT_SECURITY_MEDIUM:
 500			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT;
 501			break;
 502		case BT_SECURITY_HIGH:
 503			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
 504			      L2CAP_LM_SECURE;
 505			break;
 506		case BT_SECURITY_FIPS:
 507			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
 508			      L2CAP_LM_SECURE | L2CAP_LM_FIPS;
 509			break;
 510		default:
 511			opt = 0;
 512			break;
 513		}
 514
 515		if (test_bit(FLAG_ROLE_SWITCH, &chan->flags))
 516			opt |= L2CAP_LM_MASTER;
 517
 518		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
 519			opt |= L2CAP_LM_RELIABLE;
 520
 521		if (put_user(opt, (u32 __user *) optval))
 522			err = -EFAULT;
 523
 524		break;
 525
 526	case L2CAP_CONNINFO:
 527		if (sk->sk_state != BT_CONNECTED &&
 528		    !(sk->sk_state == BT_CONNECT2 &&
 529		      test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))) {
 530			err = -ENOTCONN;
 531			break;
 532		}
 533
 534		memset(&cinfo, 0, sizeof(cinfo));
 535		cinfo.hci_handle = chan->conn->hcon->handle;
 536		memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3);
 537
 538		len = min_t(unsigned int, len, sizeof(cinfo));
 539		if (copy_to_user(optval, (char *) &cinfo, len))
 540			err = -EFAULT;
 541
 542		break;
 543
 544	default:
 545		err = -ENOPROTOOPT;
 546		break;
 547	}
 548
 549	release_sock(sk);
 550	return err;
 551}
 552
 553static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
 554				 char __user *optval, int __user *optlen)
 555{
 556	struct sock *sk = sock->sk;
 557	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 558	struct bt_security sec;
 559	struct bt_power pwr;
 560	u32 phys;
 561	int len, mode, err = 0;
 562
 563	BT_DBG("sk %p", sk);
 564
 565	if (level == SOL_L2CAP)
 566		return l2cap_sock_getsockopt_old(sock, optname, optval, optlen);
 567
 568	if (level != SOL_BLUETOOTH)
 569		return -ENOPROTOOPT;
 570
 571	if (get_user(len, optlen))
 572		return -EFAULT;
 573
 574	lock_sock(sk);
 575
 576	switch (optname) {
 577	case BT_SECURITY:
 578		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
 579		    chan->chan_type != L2CAP_CHAN_FIXED &&
 580		    chan->chan_type != L2CAP_CHAN_RAW) {
 581			err = -EINVAL;
 582			break;
 583		}
 584
 585		memset(&sec, 0, sizeof(sec));
 586		if (chan->conn) {
 587			sec.level = chan->conn->hcon->sec_level;
 588
 589			if (sk->sk_state == BT_CONNECTED)
 590				sec.key_size = chan->conn->hcon->enc_key_size;
 591		} else {
 592			sec.level = chan->sec_level;
 593		}
 594
 595		len = min_t(unsigned int, len, sizeof(sec));
 596		if (copy_to_user(optval, (char *) &sec, len))
 597			err = -EFAULT;
 598
 599		break;
 600
 601	case BT_DEFER_SETUP:
 602		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
 603			err = -EINVAL;
 604			break;
 605		}
 606
 607		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
 608			     (u32 __user *) optval))
 609			err = -EFAULT;
 610
 611		break;
 612
 613	case BT_FLUSHABLE:
 614		if (put_user(test_bit(FLAG_FLUSHABLE, &chan->flags),
 615			     (u32 __user *) optval))
 616			err = -EFAULT;
 617
 618		break;
 619
 620	case BT_POWER:
 621		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
 622		    && sk->sk_type != SOCK_RAW) {
 623			err = -EINVAL;
 624			break;
 625		}
 626
 627		pwr.force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 628
 629		len = min_t(unsigned int, len, sizeof(pwr));
 630		if (copy_to_user(optval, (char *) &pwr, len))
 631			err = -EFAULT;
 632
 633		break;
 634
 635	case BT_CHANNEL_POLICY:
 636		if (put_user(chan->chan_policy, (u32 __user *) optval))
 637			err = -EFAULT;
 638		break;
 639
 640	case BT_SNDMTU:
 641		if (!bdaddr_type_is_le(chan->src_type)) {
 642			err = -EINVAL;
 643			break;
 644		}
 645
 646		if (sk->sk_state != BT_CONNECTED) {
 647			err = -ENOTCONN;
 648			break;
 649		}
 650
 651		if (put_user(chan->omtu, (u16 __user *) optval))
 652			err = -EFAULT;
 653		break;
 654
 655	case BT_RCVMTU:
 656		if (!bdaddr_type_is_le(chan->src_type)) {
 657			err = -EINVAL;
 658			break;
 659		}
 660
 661		if (put_user(chan->imtu, (u16 __user *) optval))
 662			err = -EFAULT;
 663		break;
 664
 665	case BT_PHY:
 666		if (sk->sk_state != BT_CONNECTED) {
 667			err = -ENOTCONN;
 668			break;
 669		}
 670
 671		phys = hci_conn_get_phy(chan->conn->hcon);
 672
 673		if (put_user(phys, (u32 __user *) optval))
 674			err = -EFAULT;
 675		break;
 676
 677	case BT_MODE:
 678		if (!enable_ecred) {
 679			err = -ENOPROTOOPT;
 680			break;
 681		}
 682
 683		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
 684			err = -EINVAL;
 685			break;
 686		}
 687
 688		mode = l2cap_get_mode(chan);
 689		if (mode < 0) {
 690			err = mode;
 691			break;
 692		}
 693
 694		if (put_user(mode, (u8 __user *) optval))
 695			err = -EFAULT;
 696		break;
 697
 698	default:
 699		err = -ENOPROTOOPT;
 700		break;
 701	}
 702
 703	release_sock(sk);
 704	return err;
 705}
 706
 707static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu)
 708{
 709	switch (chan->scid) {
 710	case L2CAP_CID_ATT:
 711		if (mtu < L2CAP_LE_MIN_MTU)
 712			return false;
 713		break;
 714
 715	default:
 716		if (mtu < L2CAP_DEFAULT_MIN_MTU)
 717			return false;
 718	}
 719
 720	return true;
 721}
 722
 723static int l2cap_sock_setsockopt_old(struct socket *sock, int optname,
 724				     sockptr_t optval, unsigned int optlen)
 725{
 726	struct sock *sk = sock->sk;
 727	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 728	struct l2cap_options opts;
 729	int len, err = 0;
 730	u32 opt;
 731
 732	BT_DBG("sk %p", sk);
 733
 734	lock_sock(sk);
 735
 736	switch (optname) {
 737	case L2CAP_OPTIONS:
 738		if (bdaddr_type_is_le(chan->src_type)) {
 739			err = -EINVAL;
 740			break;
 741		}
 742
 743		if (sk->sk_state == BT_CONNECTED) {
 744			err = -EINVAL;
 745			break;
 746		}
 747
 748		opts.imtu     = chan->imtu;
 749		opts.omtu     = chan->omtu;
 750		opts.flush_to = chan->flush_to;
 751		opts.mode     = chan->mode;
 752		opts.fcs      = chan->fcs;
 753		opts.max_tx   = chan->max_tx;
 754		opts.txwin_size = chan->tx_win;
 755
 756		len = min_t(unsigned int, sizeof(opts), optlen);
 757		if (copy_from_sockptr(&opts, optval, len)) {
 758			err = -EFAULT;
 759			break;
 760		}
 761
 762		if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) {
 763			err = -EINVAL;
 764			break;
 765		}
 766
 767		if (!l2cap_valid_mtu(chan, opts.imtu)) {
 768			err = -EINVAL;
 769			break;
 770		}
 771
 772		/* Only BR/EDR modes are supported here */
 773		switch (opts.mode) {
 774		case L2CAP_MODE_BASIC:
 775			clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
 776			break;
 777		case L2CAP_MODE_ERTM:
 778		case L2CAP_MODE_STREAMING:
 779			if (!disable_ertm)
 780				break;
 781			fallthrough;
 782		default:
 783			err = -EINVAL;
 784			break;
 785		}
 786
 787		if (err < 0)
 788			break;
 789
 790		chan->mode = opts.mode;
 791
 792		BT_DBG("mode 0x%2.2x", chan->mode);
 793
 794		chan->imtu = opts.imtu;
 795		chan->omtu = opts.omtu;
 796		chan->fcs  = opts.fcs;
 797		chan->max_tx = opts.max_tx;
 798		chan->tx_win = opts.txwin_size;
 799		chan->flush_to = opts.flush_to;
 800		break;
 801
 802	case L2CAP_LM:
 803		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
 804			err = -EFAULT;
 805			break;
 806		}
 807
 808		if (opt & L2CAP_LM_FIPS) {
 809			err = -EINVAL;
 810			break;
 811		}
 812
 813		if (opt & L2CAP_LM_AUTH)
 814			chan->sec_level = BT_SECURITY_LOW;
 815		if (opt & L2CAP_LM_ENCRYPT)
 816			chan->sec_level = BT_SECURITY_MEDIUM;
 817		if (opt & L2CAP_LM_SECURE)
 818			chan->sec_level = BT_SECURITY_HIGH;
 819
 820		if (opt & L2CAP_LM_MASTER)
 821			set_bit(FLAG_ROLE_SWITCH, &chan->flags);
 822		else
 823			clear_bit(FLAG_ROLE_SWITCH, &chan->flags);
 824
 825		if (opt & L2CAP_LM_RELIABLE)
 826			set_bit(FLAG_FORCE_RELIABLE, &chan->flags);
 827		else
 828			clear_bit(FLAG_FORCE_RELIABLE, &chan->flags);
 829		break;
 830
 831	default:
 832		err = -ENOPROTOOPT;
 833		break;
 834	}
 835
 836	release_sock(sk);
 837	return err;
 838}
 839
 840static int l2cap_set_mode(struct l2cap_chan *chan, u8 mode)
 841{
 842	switch (mode) {
 843	case BT_MODE_BASIC:
 844		if (bdaddr_type_is_le(chan->src_type))
 845			return -EINVAL;
 846		mode = L2CAP_MODE_BASIC;
 847		clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
 848		break;
 849	case BT_MODE_ERTM:
 850		if (!disable_ertm || bdaddr_type_is_le(chan->src_type))
 851			return -EINVAL;
 852		mode = L2CAP_MODE_ERTM;
 853		break;
 854	case BT_MODE_STREAMING:
 855		if (!disable_ertm || bdaddr_type_is_le(chan->src_type))
 856			return -EINVAL;
 857		mode = L2CAP_MODE_STREAMING;
 858		break;
 859	case BT_MODE_LE_FLOWCTL:
 860		if (!bdaddr_type_is_le(chan->src_type))
 861			return -EINVAL;
 862		mode = L2CAP_MODE_LE_FLOWCTL;
 863		break;
 864	case BT_MODE_EXT_FLOWCTL:
 865		/* TODO: Add support for ECRED PDUs to BR/EDR */
 866		if (!bdaddr_type_is_le(chan->src_type))
 867			return -EINVAL;
 868		mode = L2CAP_MODE_EXT_FLOWCTL;
 869		break;
 870	default:
 871		return -EINVAL;
 872	}
 873
 874	chan->mode = mode;
 875
 876	return 0;
 877}
 878
 879static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname,
 880				 sockptr_t optval, unsigned int optlen)
 881{
 882	struct sock *sk = sock->sk;
 883	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 884	struct bt_security sec;
 885	struct bt_power pwr;
 886	struct l2cap_conn *conn;
 887	int len, err = 0;
 888	u32 opt;
 889	u16 mtu;
 890	u8 mode;
 891
 892	BT_DBG("sk %p", sk);
 893
 894	if (level == SOL_L2CAP)
 895		return l2cap_sock_setsockopt_old(sock, optname, optval, optlen);
 896
 897	if (level != SOL_BLUETOOTH)
 898		return -ENOPROTOOPT;
 899
 900	lock_sock(sk);
 901
 902	switch (optname) {
 903	case BT_SECURITY:
 904		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
 905		    chan->chan_type != L2CAP_CHAN_FIXED &&
 906		    chan->chan_type != L2CAP_CHAN_RAW) {
 907			err = -EINVAL;
 908			break;
 909		}
 910
 911		sec.level = BT_SECURITY_LOW;
 912
 913		len = min_t(unsigned int, sizeof(sec), optlen);
 914		if (copy_from_sockptr(&sec, optval, len)) {
 915			err = -EFAULT;
 916			break;
 917		}
 918
 919		if (sec.level < BT_SECURITY_LOW ||
 920		    sec.level > BT_SECURITY_FIPS) {
 921			err = -EINVAL;
 922			break;
 923		}
 924
 925		chan->sec_level = sec.level;
 926
 927		if (!chan->conn)
 928			break;
 929
 930		conn = chan->conn;
 931
 932		/* change security for LE channels */
 933		if (chan->scid == L2CAP_CID_ATT) {
 934			if (smp_conn_security(conn->hcon, sec.level)) {
 935				err = -EINVAL;
 936				break;
 937			}
 938
 939			set_bit(FLAG_PENDING_SECURITY, &chan->flags);
 940			sk->sk_state = BT_CONFIG;
 941			chan->state = BT_CONFIG;
 942
 943		/* or for ACL link */
 944		} else if ((sk->sk_state == BT_CONNECT2 &&
 945			    test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) ||
 946			   sk->sk_state == BT_CONNECTED) {
 947			if (!l2cap_chan_check_security(chan, true))
 948				set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
 949			else
 950				sk->sk_state_change(sk);
 951		} else {
 952			err = -EINVAL;
 953		}
 954		break;
 955
 956	case BT_DEFER_SETUP:
 957		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
 958			err = -EINVAL;
 959			break;
 960		}
 961
 962		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
 963			err = -EFAULT;
 964			break;
 965		}
 966
 967		if (opt) {
 968			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
 969			set_bit(FLAG_DEFER_SETUP, &chan->flags);
 970		} else {
 971			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
 972			clear_bit(FLAG_DEFER_SETUP, &chan->flags);
 973		}
 974		break;
 975
 976	case BT_FLUSHABLE:
 977		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
 978			err = -EFAULT;
 979			break;
 980		}
 981
 982		if (opt > BT_FLUSHABLE_ON) {
 983			err = -EINVAL;
 984			break;
 985		}
 986
 987		if (opt == BT_FLUSHABLE_OFF) {
 988			conn = chan->conn;
 989			/* proceed further only when we have l2cap_conn and
 990			   No Flush support in the LM */
 991			if (!conn || !lmp_no_flush_capable(conn->hcon->hdev)) {
 992				err = -EINVAL;
 993				break;
 994			}
 995		}
 996
 997		if (opt)
 998			set_bit(FLAG_FLUSHABLE, &chan->flags);
 999		else
1000			clear_bit(FLAG_FLUSHABLE, &chan->flags);
1001		break;
1002
1003	case BT_POWER:
1004		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
1005		    chan->chan_type != L2CAP_CHAN_RAW) {
1006			err = -EINVAL;
1007			break;
1008		}
1009
1010		pwr.force_active = BT_POWER_FORCE_ACTIVE_ON;
1011
1012		len = min_t(unsigned int, sizeof(pwr), optlen);
1013		if (copy_from_sockptr(&pwr, optval, len)) {
1014			err = -EFAULT;
1015			break;
1016		}
1017
1018		if (pwr.force_active)
1019			set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
1020		else
1021			clear_bit(FLAG_FORCE_ACTIVE, &chan->flags);
1022		break;
1023
1024	case BT_CHANNEL_POLICY:
1025		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
1026			err = -EFAULT;
1027			break;
1028		}
1029
1030		if (opt > BT_CHANNEL_POLICY_AMP_PREFERRED) {
1031			err = -EINVAL;
1032			break;
1033		}
1034
1035		if (chan->mode != L2CAP_MODE_ERTM &&
1036		    chan->mode != L2CAP_MODE_STREAMING) {
1037			err = -EOPNOTSUPP;
1038			break;
1039		}
1040
1041		chan->chan_policy = (u8) opt;
1042
1043		if (sk->sk_state == BT_CONNECTED &&
1044		    chan->move_role == L2CAP_MOVE_ROLE_NONE)
1045			l2cap_move_start(chan);
1046
1047		break;
1048
1049	case BT_SNDMTU:
1050		if (!bdaddr_type_is_le(chan->src_type)) {
1051			err = -EINVAL;
1052			break;
1053		}
1054
1055		/* Setting is not supported as it's the remote side that
1056		 * decides this.
1057		 */
1058		err = -EPERM;
1059		break;
1060
1061	case BT_RCVMTU:
1062		if (!bdaddr_type_is_le(chan->src_type)) {
1063			err = -EINVAL;
1064			break;
1065		}
1066
1067		if (chan->mode == L2CAP_MODE_LE_FLOWCTL &&
1068		    sk->sk_state == BT_CONNECTED) {
1069			err = -EISCONN;
1070			break;
1071		}
1072
1073		if (copy_from_sockptr(&mtu, optval, sizeof(u16))) {
1074			err = -EFAULT;
1075			break;
1076		}
1077
1078		if (chan->mode == L2CAP_MODE_EXT_FLOWCTL &&
1079		    sk->sk_state == BT_CONNECTED)
1080			err = l2cap_chan_reconfigure(chan, mtu);
1081		else
1082			chan->imtu = mtu;
1083
1084		break;
1085
1086	case BT_MODE:
1087		if (!enable_ecred) {
1088			err = -ENOPROTOOPT;
1089			break;
1090		}
1091
1092		BT_DBG("sk->sk_state %u", sk->sk_state);
1093
1094		if (sk->sk_state != BT_BOUND) {
1095			err = -EINVAL;
1096			break;
1097		}
1098
1099		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1100			err = -EINVAL;
1101			break;
1102		}
1103
1104		if (copy_from_sockptr(&mode, optval, sizeof(u8))) {
1105			err = -EFAULT;
1106			break;
1107		}
1108
1109		BT_DBG("mode %u", mode);
1110
1111		err = l2cap_set_mode(chan, mode);
1112		if (err)
1113			break;
1114
1115		BT_DBG("mode 0x%2.2x", chan->mode);
1116
1117		break;
1118
1119	default:
1120		err = -ENOPROTOOPT;
1121		break;
1122	}
1123
1124	release_sock(sk);
1125	return err;
1126}
1127
1128static int l2cap_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1129			      size_t len)
1130{
1131	struct sock *sk = sock->sk;
1132	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1133	int err;
1134
1135	BT_DBG("sock %p, sk %p", sock, sk);
1136
1137	err = sock_error(sk);
1138	if (err)
1139		return err;
1140
1141	if (msg->msg_flags & MSG_OOB)
1142		return -EOPNOTSUPP;
1143
1144	if (sk->sk_state != BT_CONNECTED)
1145		return -ENOTCONN;
1146
1147	lock_sock(sk);
1148	err = bt_sock_wait_ready(sk, msg->msg_flags);
1149	release_sock(sk);
1150	if (err)
1151		return err;
1152
1153	l2cap_chan_lock(chan);
1154	err = l2cap_chan_send(chan, msg, len);
1155	l2cap_chan_unlock(chan);
1156
1157	return err;
1158}
1159
1160static int l2cap_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1161			      size_t len, int flags)
1162{
1163	struct sock *sk = sock->sk;
1164	struct l2cap_pinfo *pi = l2cap_pi(sk);
1165	int err;
1166
1167	lock_sock(sk);
1168
1169	if (sk->sk_state == BT_CONNECT2 && test_bit(BT_SK_DEFER_SETUP,
1170						    &bt_sk(sk)->flags)) {
1171		if (pi->chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
1172			sk->sk_state = BT_CONNECTED;
1173			pi->chan->state = BT_CONNECTED;
1174			__l2cap_ecred_conn_rsp_defer(pi->chan);
1175		} else if (bdaddr_type_is_le(pi->chan->src_type)) {
1176			sk->sk_state = BT_CONNECTED;
1177			pi->chan->state = BT_CONNECTED;
1178			__l2cap_le_connect_rsp_defer(pi->chan);
1179		} else {
1180			sk->sk_state = BT_CONFIG;
1181			pi->chan->state = BT_CONFIG;
1182			__l2cap_connect_rsp_defer(pi->chan);
1183		}
1184
1185		err = 0;
1186		goto done;
1187	}
1188
1189	release_sock(sk);
1190
1191	if (sock->type == SOCK_STREAM)
1192		err = bt_sock_stream_recvmsg(sock, msg, len, flags);
1193	else
1194		err = bt_sock_recvmsg(sock, msg, len, flags);
1195
1196	if (pi->chan->mode != L2CAP_MODE_ERTM)
1197		return err;
1198
1199	/* Attempt to put pending rx data in the socket buffer */
1200
1201	lock_sock(sk);
1202
1203	if (!test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state))
1204		goto done;
1205
1206	if (pi->rx_busy_skb) {
1207		if (!__sock_queue_rcv_skb(sk, pi->rx_busy_skb))
1208			pi->rx_busy_skb = NULL;
1209		else
1210			goto done;
1211	}
1212
1213	/* Restore data flow when half of the receive buffer is
1214	 * available.  This avoids resending large numbers of
1215	 * frames.
1216	 */
1217	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1)
1218		l2cap_chan_busy(pi->chan, 0);
1219
1220done:
1221	release_sock(sk);
1222	return err;
1223}
1224
1225/* Kill socket (only if zapped and orphan)
1226 * Must be called on unlocked socket, with l2cap channel lock.
1227 */
1228static void l2cap_sock_kill(struct sock *sk)
1229{
1230	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
1231		return;
1232
1233	BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state));
1234
1235	/* Kill poor orphan */
1236
1237	l2cap_chan_put(l2cap_pi(sk)->chan);
1238	sock_set_flag(sk, SOCK_DEAD);
1239	sock_put(sk);
1240}
1241
1242static int __l2cap_wait_ack(struct sock *sk, struct l2cap_chan *chan)
1243{
1244	DECLARE_WAITQUEUE(wait, current);
1245	int err = 0;
1246	int timeo = L2CAP_WAIT_ACK_POLL_PERIOD;
1247	/* Timeout to prevent infinite loop */
1248	unsigned long timeout = jiffies + L2CAP_WAIT_ACK_TIMEOUT;
1249
1250	add_wait_queue(sk_sleep(sk), &wait);
1251	set_current_state(TASK_INTERRUPTIBLE);
1252	do {
1253		BT_DBG("Waiting for %d ACKs, timeout %04d ms",
1254		       chan->unacked_frames, time_after(jiffies, timeout) ? 0 :
1255		       jiffies_to_msecs(timeout - jiffies));
1256
1257		if (!timeo)
1258			timeo = L2CAP_WAIT_ACK_POLL_PERIOD;
1259
1260		if (signal_pending(current)) {
1261			err = sock_intr_errno(timeo);
1262			break;
1263		}
1264
1265		release_sock(sk);
1266		timeo = schedule_timeout(timeo);
1267		lock_sock(sk);
1268		set_current_state(TASK_INTERRUPTIBLE);
1269
1270		err = sock_error(sk);
1271		if (err)
1272			break;
1273
1274		if (time_after(jiffies, timeout)) {
1275			err = -ENOLINK;
1276			break;
1277		}
1278
1279	} while (chan->unacked_frames > 0 &&
1280		 chan->state == BT_CONNECTED);
1281
1282	set_current_state(TASK_RUNNING);
1283	remove_wait_queue(sk_sleep(sk), &wait);
1284	return err;
1285}
1286
1287static int l2cap_sock_shutdown(struct socket *sock, int how)
1288{
1289	struct sock *sk = sock->sk;
1290	struct l2cap_chan *chan;
1291	struct l2cap_conn *conn;
1292	int err = 0;
1293
1294	BT_DBG("sock %p, sk %p, how %d", sock, sk, how);
1295
1296	/* 'how' parameter is mapped to sk_shutdown as follows:
1297	 * SHUT_RD   (0) --> RCV_SHUTDOWN  (1)
1298	 * SHUT_WR   (1) --> SEND_SHUTDOWN (2)
1299	 * SHUT_RDWR (2) --> SHUTDOWN_MASK (3)
1300	 */
1301	how++;
1302
1303	if (!sk)
1304		return 0;
1305
1306	lock_sock(sk);
1307
1308	if ((sk->sk_shutdown & how) == how)
1309		goto shutdown_already;
1310
1311	BT_DBG("Handling sock shutdown");
1312
1313	/* prevent sk structure from being freed whilst unlocked */
1314	sock_hold(sk);
1315
1316	chan = l2cap_pi(sk)->chan;
1317	/* prevent chan structure from being freed whilst unlocked */
1318	l2cap_chan_hold(chan);
1319
1320	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
1321
1322	if (chan->mode == L2CAP_MODE_ERTM &&
1323	    chan->unacked_frames > 0 &&
1324	    chan->state == BT_CONNECTED) {
1325		err = __l2cap_wait_ack(sk, chan);
1326
1327		/* After waiting for ACKs, check whether shutdown
1328		 * has already been actioned to close the L2CAP
1329		 * link such as by l2cap_disconnection_req().
1330		 */
1331		if ((sk->sk_shutdown & how) == how)
1332			goto shutdown_matched;
1333	}
1334
1335	/* Try setting the RCV_SHUTDOWN bit, return early if SEND_SHUTDOWN
1336	 * is already set
1337	 */
1338	if ((how & RCV_SHUTDOWN) && !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1339		sk->sk_shutdown |= RCV_SHUTDOWN;
1340		if ((sk->sk_shutdown & how) == how)
1341			goto shutdown_matched;
1342	}
1343
1344	sk->sk_shutdown |= SEND_SHUTDOWN;
1345	release_sock(sk);
1346
1347	l2cap_chan_lock(chan);
1348	conn = chan->conn;
1349	if (conn)
1350		/* prevent conn structure from being freed */
1351		l2cap_conn_get(conn);
1352	l2cap_chan_unlock(chan);
1353
1354	if (conn)
1355		/* mutex lock must be taken before l2cap_chan_lock() */
1356		mutex_lock(&conn->chan_lock);
1357
1358	l2cap_chan_lock(chan);
1359	l2cap_chan_close(chan, 0);
1360	l2cap_chan_unlock(chan);
1361
1362	if (conn) {
1363		mutex_unlock(&conn->chan_lock);
1364		l2cap_conn_put(conn);
1365	}
1366
1367	lock_sock(sk);
1368
1369	if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime &&
1370	    !(current->flags & PF_EXITING))
1371		err = bt_sock_wait_state(sk, BT_CLOSED,
1372					 sk->sk_lingertime);
1373
1374shutdown_matched:
1375	l2cap_chan_put(chan);
1376	sock_put(sk);
1377
1378shutdown_already:
1379	if (!err && sk->sk_err)
1380		err = -sk->sk_err;
1381
1382	release_sock(sk);
1383
1384	BT_DBG("Sock shutdown complete err: %d", err);
1385
1386	return err;
1387}
1388
1389static int l2cap_sock_release(struct socket *sock)
1390{
1391	struct sock *sk = sock->sk;
1392	int err;
1393	struct l2cap_chan *chan;
1394
1395	BT_DBG("sock %p, sk %p", sock, sk);
1396
1397	if (!sk)
1398		return 0;
1399
1400	l2cap_sock_cleanup_listen(sk);
1401	bt_sock_unlink(&l2cap_sk_list, sk);
1402
1403	err = l2cap_sock_shutdown(sock, SHUT_RDWR);
1404	chan = l2cap_pi(sk)->chan;
1405
1406	l2cap_chan_hold(chan);
1407	l2cap_chan_lock(chan);
1408
1409	sock_orphan(sk);
1410	l2cap_sock_kill(sk);
1411
1412	l2cap_chan_unlock(chan);
1413	l2cap_chan_put(chan);
1414
1415	return err;
1416}
1417
1418static void l2cap_sock_cleanup_listen(struct sock *parent)
1419{
1420	struct sock *sk;
1421
1422	BT_DBG("parent %p state %s", parent,
1423	       state_to_string(parent->sk_state));
1424
1425	/* Close not yet accepted channels */
1426	while ((sk = bt_accept_dequeue(parent, NULL))) {
1427		struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1428
1429		BT_DBG("child chan %p state %s", chan,
1430		       state_to_string(chan->state));
1431
1432		l2cap_chan_hold(chan);
1433		l2cap_chan_lock(chan);
1434
1435		__clear_chan_timer(chan);
1436		l2cap_chan_close(chan, ECONNRESET);
1437		l2cap_sock_kill(sk);
1438
1439		l2cap_chan_unlock(chan);
1440		l2cap_chan_put(chan);
1441	}
1442}
1443
1444static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
1445{
1446	struct sock *sk, *parent = chan->data;
1447
1448	lock_sock(parent);
1449
1450	/* Check for backlog size */
1451	if (sk_acceptq_is_full(parent)) {
1452		BT_DBG("backlog full %d", parent->sk_ack_backlog);
1453		release_sock(parent);
1454		return NULL;
1455	}
1456
1457	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP,
1458			      GFP_ATOMIC, 0);
1459	if (!sk) {
1460		release_sock(parent);
1461		return NULL;
1462        }
1463
1464	bt_sock_reclassify_lock(sk, BTPROTO_L2CAP);
1465
1466	l2cap_sock_init(sk, parent);
1467
1468	bt_accept_enqueue(parent, sk, false);
1469
1470	release_sock(parent);
1471
1472	return l2cap_pi(sk)->chan;
1473}
1474
1475static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
1476{
1477	struct sock *sk = chan->data;
1478	int err;
1479
1480	lock_sock(sk);
1481
1482	if (l2cap_pi(sk)->rx_busy_skb) {
1483		err = -ENOMEM;
1484		goto done;
1485	}
1486
1487	if (chan->mode != L2CAP_MODE_ERTM &&
1488	    chan->mode != L2CAP_MODE_STREAMING) {
1489		/* Even if no filter is attached, we could potentially
1490		 * get errors from security modules, etc.
1491		 */
1492		err = sk_filter(sk, skb);
1493		if (err)
1494			goto done;
1495	}
1496
1497	err = __sock_queue_rcv_skb(sk, skb);
1498
1499	/* For ERTM, handle one skb that doesn't fit into the recv
1500	 * buffer.  This is important to do because the data frames
1501	 * have already been acked, so the skb cannot be discarded.
1502	 *
1503	 * Notify the l2cap core that the buffer is full, so the
1504	 * LOCAL_BUSY state is entered and no more frames are
1505	 * acked and reassembled until there is buffer space
1506	 * available.
1507	 */
1508	if (err < 0 && chan->mode == L2CAP_MODE_ERTM) {
1509		l2cap_pi(sk)->rx_busy_skb = skb;
1510		l2cap_chan_busy(chan, 1);
1511		err = 0;
1512	}
1513
1514done:
1515	release_sock(sk);
1516
1517	return err;
1518}
1519
1520static void l2cap_sock_close_cb(struct l2cap_chan *chan)
1521{
1522	struct sock *sk = chan->data;
1523
1524	if (!sk)
1525		return;
1526
1527	l2cap_sock_kill(sk);
1528}
1529
1530static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err)
1531{
1532	struct sock *sk = chan->data;
1533	struct sock *parent;
1534
1535	if (!sk)
1536		return;
1537
1538	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
1539
1540	/* This callback can be called both for server (BT_LISTEN)
1541	 * sockets as well as "normal" ones. To avoid lockdep warnings
1542	 * with child socket locking (through l2cap_sock_cleanup_listen)
1543	 * we need separation into separate nesting levels. The simplest
1544	 * way to accomplish this is to inherit the nesting level used
1545	 * for the channel.
1546	 */
1547	lock_sock_nested(sk, atomic_read(&chan->nesting));
1548
1549	parent = bt_sk(sk)->parent;
1550
1551	switch (chan->state) {
1552	case BT_OPEN:
1553	case BT_BOUND:
1554	case BT_CLOSED:
1555		break;
1556	case BT_LISTEN:
1557		l2cap_sock_cleanup_listen(sk);
1558		sk->sk_state = BT_CLOSED;
1559		chan->state = BT_CLOSED;
1560
1561		break;
1562	default:
1563		sk->sk_state = BT_CLOSED;
1564		chan->state = BT_CLOSED;
1565
1566		sk->sk_err = err;
1567
1568		if (parent) {
1569			bt_accept_unlink(sk);
1570			parent->sk_data_ready(parent);
1571		} else {
1572			sk->sk_state_change(sk);
1573		}
1574
1575		break;
1576	}
1577	release_sock(sk);
1578
1579	/* Only zap after cleanup to avoid use after free race */
1580	sock_set_flag(sk, SOCK_ZAPPED);
1581
1582}
1583
1584static void l2cap_sock_state_change_cb(struct l2cap_chan *chan, int state,
1585				       int err)
1586{
1587	struct sock *sk = chan->data;
1588
1589	sk->sk_state = state;
1590
1591	if (err)
1592		sk->sk_err = err;
1593}
1594
1595static struct sk_buff *l2cap_sock_alloc_skb_cb(struct l2cap_chan *chan,
1596					       unsigned long hdr_len,
1597					       unsigned long len, int nb)
1598{
1599	struct sock *sk = chan->data;
1600	struct sk_buff *skb;
1601	int err;
1602
1603	l2cap_chan_unlock(chan);
1604	skb = bt_skb_send_alloc(sk, hdr_len + len, nb, &err);
1605	l2cap_chan_lock(chan);
1606
1607	if (!skb)
1608		return ERR_PTR(err);
1609
1610	/* Channel lock is released before requesting new skb and then
1611	 * reacquired thus we need to recheck channel state.
1612	 */
1613	if (chan->state != BT_CONNECTED) {
1614		kfree_skb(skb);
1615		return ERR_PTR(-ENOTCONN);
1616	}
1617
1618	skb->priority = READ_ONCE(sk->sk_priority);
1619
1620	bt_cb(skb)->l2cap.chan = chan;
1621
1622	return skb;
1623}
1624
1625static void l2cap_sock_ready_cb(struct l2cap_chan *chan)
1626{
1627	struct sock *sk = chan->data;
1628	struct sock *parent;
1629
1630	lock_sock(sk);
1631
1632	parent = bt_sk(sk)->parent;
1633
1634	BT_DBG("sk %p, parent %p", sk, parent);
1635
1636	sk->sk_state = BT_CONNECTED;
1637	sk->sk_state_change(sk);
1638
1639	if (parent)
1640		parent->sk_data_ready(parent);
1641
1642	release_sock(sk);
1643}
1644
1645static void l2cap_sock_defer_cb(struct l2cap_chan *chan)
1646{
1647	struct sock *parent, *sk = chan->data;
1648
1649	lock_sock(sk);
1650
1651	parent = bt_sk(sk)->parent;
1652	if (parent)
1653		parent->sk_data_ready(parent);
1654
1655	release_sock(sk);
1656}
1657
1658static void l2cap_sock_resume_cb(struct l2cap_chan *chan)
1659{
1660	struct sock *sk = chan->data;
1661
1662	if (test_and_clear_bit(FLAG_PENDING_SECURITY, &chan->flags)) {
1663		sk->sk_state = BT_CONNECTED;
1664		chan->state = BT_CONNECTED;
1665	}
1666
1667	clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
1668	sk->sk_state_change(sk);
1669}
1670
1671static void l2cap_sock_set_shutdown_cb(struct l2cap_chan *chan)
1672{
1673	struct sock *sk = chan->data;
1674
1675	lock_sock(sk);
1676	sk->sk_shutdown = SHUTDOWN_MASK;
1677	release_sock(sk);
1678}
1679
1680static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan)
1681{
1682	struct sock *sk = chan->data;
1683
1684	return sk->sk_sndtimeo;
1685}
1686
1687static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan)
1688{
1689	struct sock *sk = chan->data;
1690
1691	return sk->sk_peer_pid;
1692}
1693
1694static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
1695{
1696	struct sock *sk = chan->data;
1697
1698	set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
1699	sk->sk_state_change(sk);
1700}
1701
1702static int l2cap_sock_filter(struct l2cap_chan *chan, struct sk_buff *skb)
1703{
1704	struct sock *sk = chan->data;
1705
1706	switch (chan->mode) {
1707	case L2CAP_MODE_ERTM:
1708	case L2CAP_MODE_STREAMING:
1709		return sk_filter(sk, skb);
1710	}
1711
1712	return 0;
1713}
1714
1715static const struct l2cap_ops l2cap_chan_ops = {
1716	.name			= "L2CAP Socket Interface",
1717	.new_connection		= l2cap_sock_new_connection_cb,
1718	.recv			= l2cap_sock_recv_cb,
1719	.close			= l2cap_sock_close_cb,
1720	.teardown		= l2cap_sock_teardown_cb,
1721	.state_change		= l2cap_sock_state_change_cb,
1722	.ready			= l2cap_sock_ready_cb,
1723	.defer			= l2cap_sock_defer_cb,
1724	.resume			= l2cap_sock_resume_cb,
1725	.suspend		= l2cap_sock_suspend_cb,
1726	.set_shutdown		= l2cap_sock_set_shutdown_cb,
1727	.get_sndtimeo		= l2cap_sock_get_sndtimeo_cb,
1728	.get_peer_pid		= l2cap_sock_get_peer_pid_cb,
1729	.alloc_skb		= l2cap_sock_alloc_skb_cb,
1730	.filter			= l2cap_sock_filter,
1731};
1732
1733static void l2cap_sock_destruct(struct sock *sk)
1734{
1735	BT_DBG("sk %p", sk);
1736
1737	if (l2cap_pi(sk)->chan) {
1738		l2cap_pi(sk)->chan->data = NULL;
1739		l2cap_chan_put(l2cap_pi(sk)->chan);
1740	}
1741
1742	if (l2cap_pi(sk)->rx_busy_skb) {
1743		kfree_skb(l2cap_pi(sk)->rx_busy_skb);
1744		l2cap_pi(sk)->rx_busy_skb = NULL;
1745	}
1746
1747	skb_queue_purge(&sk->sk_receive_queue);
1748	skb_queue_purge(&sk->sk_write_queue);
1749}
1750
1751static void l2cap_skb_msg_name(struct sk_buff *skb, void *msg_name,
1752			       int *msg_namelen)
1753{
1754	DECLARE_SOCKADDR(struct sockaddr_l2 *, la, msg_name);
1755
1756	memset(la, 0, sizeof(struct sockaddr_l2));
1757	la->l2_family = AF_BLUETOOTH;
1758	la->l2_psm = bt_cb(skb)->l2cap.psm;
1759	bacpy(&la->l2_bdaddr, &bt_cb(skb)->l2cap.bdaddr);
1760
1761	*msg_namelen = sizeof(struct sockaddr_l2);
1762}
1763
1764static void l2cap_sock_init(struct sock *sk, struct sock *parent)
1765{
1766	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1767
1768	BT_DBG("sk %p", sk);
1769
1770	if (parent) {
1771		struct l2cap_chan *pchan = l2cap_pi(parent)->chan;
1772
1773		sk->sk_type = parent->sk_type;
1774		bt_sk(sk)->flags = bt_sk(parent)->flags;
1775
1776		chan->chan_type = pchan->chan_type;
1777		chan->imtu = pchan->imtu;
1778		chan->omtu = pchan->omtu;
1779		chan->conf_state = pchan->conf_state;
1780		chan->mode = pchan->mode;
1781		chan->fcs  = pchan->fcs;
1782		chan->max_tx = pchan->max_tx;
1783		chan->tx_win = pchan->tx_win;
1784		chan->tx_win_max = pchan->tx_win_max;
1785		chan->sec_level = pchan->sec_level;
1786		chan->flags = pchan->flags;
1787		chan->tx_credits = pchan->tx_credits;
1788		chan->rx_credits = pchan->rx_credits;
1789
1790		if (chan->chan_type == L2CAP_CHAN_FIXED) {
1791			chan->scid = pchan->scid;
1792			chan->dcid = pchan->scid;
1793		}
1794
1795		security_sk_clone(parent, sk);
1796	} else {
1797		switch (sk->sk_type) {
1798		case SOCK_RAW:
1799			chan->chan_type = L2CAP_CHAN_RAW;
1800			break;
1801		case SOCK_DGRAM:
1802			chan->chan_type = L2CAP_CHAN_CONN_LESS;
1803			bt_sk(sk)->skb_msg_name = l2cap_skb_msg_name;
1804			break;
1805		case SOCK_SEQPACKET:
1806		case SOCK_STREAM:
1807			chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
1808			break;
1809		}
1810
1811		chan->imtu = L2CAP_DEFAULT_MTU;
1812		chan->omtu = 0;
1813		if (!disable_ertm && sk->sk_type == SOCK_STREAM) {
1814			chan->mode = L2CAP_MODE_ERTM;
1815			set_bit(CONF_STATE2_DEVICE, &chan->conf_state);
1816		} else {
1817			chan->mode = L2CAP_MODE_BASIC;
1818		}
1819
1820		l2cap_chan_set_defaults(chan);
1821	}
1822
1823	/* Default config options */
1824	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
1825
1826	chan->data = sk;
1827	chan->ops = &l2cap_chan_ops;
1828}
1829
1830static struct proto l2cap_proto = {
1831	.name		= "L2CAP",
1832	.owner		= THIS_MODULE,
1833	.obj_size	= sizeof(struct l2cap_pinfo)
1834};
1835
1836static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
1837				     int proto, gfp_t prio, int kern)
1838{
1839	struct sock *sk;
1840	struct l2cap_chan *chan;
1841
1842	sk = bt_sock_alloc(net, sock, &l2cap_proto, proto, prio, kern);
1843	if (!sk)
1844		return NULL;
1845
 
 
 
1846	sk->sk_destruct = l2cap_sock_destruct;
1847	sk->sk_sndtimeo = L2CAP_CONN_TIMEOUT;
 
 
 
 
 
1848
1849	chan = l2cap_chan_create();
1850	if (!chan) {
1851		sk_free(sk);
1852		return NULL;
1853	}
1854
1855	l2cap_chan_hold(chan);
1856
1857	l2cap_pi(sk)->chan = chan;
1858
1859	return sk;
1860}
1861
1862static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
1863			     int kern)
1864{
1865	struct sock *sk;
1866
1867	BT_DBG("sock %p", sock);
1868
1869	sock->state = SS_UNCONNECTED;
1870
1871	if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM &&
1872	    sock->type != SOCK_DGRAM && sock->type != SOCK_RAW)
1873		return -ESOCKTNOSUPPORT;
1874
1875	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
1876		return -EPERM;
1877
1878	sock->ops = &l2cap_sock_ops;
1879
1880	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern);
1881	if (!sk)
1882		return -ENOMEM;
1883
1884	l2cap_sock_init(sk, NULL);
1885	bt_sock_link(&l2cap_sk_list, sk);
1886	return 0;
1887}
1888
1889static const struct proto_ops l2cap_sock_ops = {
1890	.family		= PF_BLUETOOTH,
1891	.owner		= THIS_MODULE,
1892	.release	= l2cap_sock_release,
1893	.bind		= l2cap_sock_bind,
1894	.connect	= l2cap_sock_connect,
1895	.listen		= l2cap_sock_listen,
1896	.accept		= l2cap_sock_accept,
1897	.getname	= l2cap_sock_getname,
1898	.sendmsg	= l2cap_sock_sendmsg,
1899	.recvmsg	= l2cap_sock_recvmsg,
1900	.poll		= bt_sock_poll,
1901	.ioctl		= bt_sock_ioctl,
1902	.gettstamp	= sock_gettstamp,
1903	.mmap		= sock_no_mmap,
1904	.socketpair	= sock_no_socketpair,
1905	.shutdown	= l2cap_sock_shutdown,
1906	.setsockopt	= l2cap_sock_setsockopt,
1907	.getsockopt	= l2cap_sock_getsockopt
1908};
1909
1910static const struct net_proto_family l2cap_sock_family_ops = {
1911	.family	= PF_BLUETOOTH,
1912	.owner	= THIS_MODULE,
1913	.create	= l2cap_sock_create,
1914};
1915
1916int __init l2cap_init_sockets(void)
1917{
1918	int err;
1919
1920	BUILD_BUG_ON(sizeof(struct sockaddr_l2) > sizeof(struct sockaddr));
1921
1922	err = proto_register(&l2cap_proto, 0);
1923	if (err < 0)
1924		return err;
1925
1926	err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops);
1927	if (err < 0) {
1928		BT_ERR("L2CAP socket registration failed");
1929		goto error;
1930	}
1931
1932	err = bt_procfs_init(&init_net, "l2cap", &l2cap_sk_list,
1933			     NULL);
1934	if (err < 0) {
1935		BT_ERR("Failed to create L2CAP proc file");
1936		bt_sock_unregister(BTPROTO_L2CAP);
1937		goto error;
1938	}
1939
1940	BT_INFO("L2CAP socket layer initialized");
1941
1942	return 0;
1943
1944error:
1945	proto_unregister(&l2cap_proto);
1946	return err;
1947}
1948
1949void l2cap_cleanup_sockets(void)
1950{
1951	bt_procfs_cleanup(&init_net, "l2cap");
1952	bt_sock_unregister(BTPROTO_L2CAP);
1953	proto_unregister(&l2cap_proto);
1954}
v6.2
   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#include <linux/filter.h>
  33#include <linux/sched/signal.h>
  34
  35#include <net/bluetooth/bluetooth.h>
  36#include <net/bluetooth/hci_core.h>
  37#include <net/bluetooth/l2cap.h>
  38
  39#include "smp.h"
  40
  41static struct bt_sock_list l2cap_sk_list = {
  42	.lock = __RW_LOCK_UNLOCKED(l2cap_sk_list.lock)
  43};
  44
  45static const struct proto_ops l2cap_sock_ops;
  46static void l2cap_sock_init(struct sock *sk, struct sock *parent);
  47static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
  48				     int proto, gfp_t prio, int kern);
 
  49
  50bool l2cap_is_socket(struct socket *sock)
  51{
  52	return sock && sock->ops == &l2cap_sock_ops;
  53}
  54EXPORT_SYMBOL(l2cap_is_socket);
  55
  56static int l2cap_validate_bredr_psm(u16 psm)
  57{
  58	/* PSM must be odd and lsb of upper byte must be 0 */
  59	if ((psm & 0x0101) != 0x0001)
  60		return -EINVAL;
  61
  62	/* Restrict usage of well-known PSMs */
  63	if (psm < L2CAP_PSM_DYN_START && !capable(CAP_NET_BIND_SERVICE))
  64		return -EACCES;
  65
  66	return 0;
  67}
  68
  69static int l2cap_validate_le_psm(u16 psm)
  70{
  71	/* Valid LE_PSM ranges are defined only until 0x00ff */
  72	if (psm > L2CAP_PSM_LE_DYN_END)
  73		return -EINVAL;
  74
  75	/* Restrict fixed, SIG assigned PSM values to CAP_NET_BIND_SERVICE */
  76	if (psm < L2CAP_PSM_LE_DYN_START && !capable(CAP_NET_BIND_SERVICE))
  77		return -EACCES;
  78
  79	return 0;
  80}
  81
  82static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
  83{
  84	struct sock *sk = sock->sk;
  85	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
  86	struct sockaddr_l2 la;
  87	int len, err = 0;
  88
  89	BT_DBG("sk %p", sk);
  90
  91	if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
  92	    addr->sa_family != AF_BLUETOOTH)
  93		return -EINVAL;
  94
  95	memset(&la, 0, sizeof(la));
  96	len = min_t(unsigned int, sizeof(la), alen);
  97	memcpy(&la, addr, len);
  98
  99	if (la.l2_cid && la.l2_psm)
 100		return -EINVAL;
 101
 102	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
 103		return -EINVAL;
 104
 105	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
 106		/* We only allow ATT user space socket */
 107		if (la.l2_cid &&
 108		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
 109			return -EINVAL;
 110	}
 111
 112	lock_sock(sk);
 113
 114	if (sk->sk_state != BT_OPEN) {
 115		err = -EBADFD;
 116		goto done;
 117	}
 118
 119	if (la.l2_psm) {
 120		__u16 psm = __le16_to_cpu(la.l2_psm);
 121
 122		if (la.l2_bdaddr_type == BDADDR_BREDR)
 123			err = l2cap_validate_bredr_psm(psm);
 124		else
 125			err = l2cap_validate_le_psm(psm);
 126
 127		if (err)
 128			goto done;
 129	}
 130
 131	bacpy(&chan->src, &la.l2_bdaddr);
 132	chan->src_type = la.l2_bdaddr_type;
 133
 134	if (la.l2_cid)
 135		err = l2cap_add_scid(chan, __le16_to_cpu(la.l2_cid));
 136	else
 137		err = l2cap_add_psm(chan, &la.l2_bdaddr, la.l2_psm);
 138
 139	if (err < 0)
 140		goto done;
 141
 142	switch (chan->chan_type) {
 143	case L2CAP_CHAN_CONN_LESS:
 144		if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_3DSP)
 145			chan->sec_level = BT_SECURITY_SDP;
 146		break;
 147	case L2CAP_CHAN_CONN_ORIENTED:
 148		if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_SDP ||
 149		    __le16_to_cpu(la.l2_psm) == L2CAP_PSM_RFCOMM)
 150			chan->sec_level = BT_SECURITY_SDP;
 151		break;
 152	case L2CAP_CHAN_RAW:
 153		chan->sec_level = BT_SECURITY_SDP;
 154		break;
 155	case L2CAP_CHAN_FIXED:
 156		/* Fixed channels default to the L2CAP core not holding a
 157		 * hci_conn reference for them. For fixed channels mapping to
 158		 * L2CAP sockets we do want to hold a reference so set the
 159		 * appropriate flag to request it.
 160		 */
 161		set_bit(FLAG_HOLD_HCI_CONN, &chan->flags);
 162		break;
 163	}
 164
 165	/* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and
 166	 * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set.
 167	 */
 168	if (chan->psm && bdaddr_type_is_le(chan->src_type) &&
 169	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 170		chan->mode = L2CAP_MODE_LE_FLOWCTL;
 171
 172	chan->state = BT_BOUND;
 173	sk->sk_state = BT_BOUND;
 174
 175done:
 176	release_sock(sk);
 177	return err;
 178}
 179
 180static void l2cap_sock_init_pid(struct sock *sk)
 181{
 182	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 183
 184	/* Only L2CAP_MODE_EXT_FLOWCTL ever need to access the PID in order to
 185	 * group the channels being requested.
 186	 */
 187	if (chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 188		return;
 189
 190	spin_lock(&sk->sk_peer_lock);
 191	sk->sk_peer_pid = get_pid(task_tgid(current));
 192	spin_unlock(&sk->sk_peer_lock);
 193}
 194
 195static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr,
 196			      int alen, int flags)
 197{
 198	struct sock *sk = sock->sk;
 199	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 200	struct sockaddr_l2 la;
 201	int len, err = 0;
 202	bool zapped;
 203
 204	BT_DBG("sk %p", sk);
 205
 206	lock_sock(sk);
 207	zapped = sock_flag(sk, SOCK_ZAPPED);
 208	release_sock(sk);
 209
 210	if (zapped)
 211		return -EINVAL;
 212
 213	if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
 214	    addr->sa_family != AF_BLUETOOTH)
 215		return -EINVAL;
 216
 217	memset(&la, 0, sizeof(la));
 218	len = min_t(unsigned int, sizeof(la), alen);
 219	memcpy(&la, addr, len);
 220
 221	if (la.l2_cid && la.l2_psm)
 222		return -EINVAL;
 223
 224	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
 225		return -EINVAL;
 226
 227	/* Check that the socket wasn't bound to something that
 228	 * conflicts with the address given to connect(). If chan->src
 229	 * is BDADDR_ANY it means bind() was never used, in which case
 230	 * chan->src_type and la.l2_bdaddr_type do not need to match.
 231	 */
 232	if (chan->src_type == BDADDR_BREDR && bacmp(&chan->src, BDADDR_ANY) &&
 233	    bdaddr_type_is_le(la.l2_bdaddr_type)) {
 234		/* Old user space versions will try to incorrectly bind
 235		 * the ATT socket using BDADDR_BREDR. We need to accept
 236		 * this and fix up the source address type only when
 237		 * both the source CID and destination CID indicate
 238		 * ATT. Anything else is an invalid combination.
 239		 */
 240		if (chan->scid != L2CAP_CID_ATT ||
 241		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
 242			return -EINVAL;
 243
 244		/* We don't have the hdev available here to make a
 245		 * better decision on random vs public, but since all
 246		 * user space versions that exhibit this issue anyway do
 247		 * not support random local addresses assuming public
 248		 * here is good enough.
 249		 */
 250		chan->src_type = BDADDR_LE_PUBLIC;
 251	}
 252
 253	if (chan->src_type != BDADDR_BREDR && la.l2_bdaddr_type == BDADDR_BREDR)
 254		return -EINVAL;
 255
 256	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
 257		/* We only allow ATT user space socket */
 258		if (la.l2_cid &&
 259		    la.l2_cid != cpu_to_le16(L2CAP_CID_ATT))
 260			return -EINVAL;
 261	}
 262
 263	/* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and
 264	 * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set.
 265	 */
 266	if (chan->psm && bdaddr_type_is_le(chan->src_type) &&
 267	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 268		chan->mode = L2CAP_MODE_LE_FLOWCTL;
 269
 270	l2cap_sock_init_pid(sk);
 271
 272	err = l2cap_chan_connect(chan, la.l2_psm, __le16_to_cpu(la.l2_cid),
 273				 &la.l2_bdaddr, la.l2_bdaddr_type);
 274	if (err)
 275		return err;
 276
 277	lock_sock(sk);
 278
 279	err = bt_sock_wait_state(sk, BT_CONNECTED,
 280				 sock_sndtimeo(sk, flags & O_NONBLOCK));
 281
 282	release_sock(sk);
 283
 284	return err;
 285}
 286
 287static int l2cap_sock_listen(struct socket *sock, int backlog)
 288{
 289	struct sock *sk = sock->sk;
 290	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 291	int err = 0;
 292
 293	BT_DBG("sk %p backlog %d", sk, backlog);
 294
 295	lock_sock(sk);
 296
 297	if (sk->sk_state != BT_BOUND) {
 298		err = -EBADFD;
 299		goto done;
 300	}
 301
 302	if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM) {
 303		err = -EINVAL;
 304		goto done;
 305	}
 306
 307	switch (chan->mode) {
 308	case L2CAP_MODE_BASIC:
 309	case L2CAP_MODE_LE_FLOWCTL:
 310		break;
 311	case L2CAP_MODE_EXT_FLOWCTL:
 312		if (!enable_ecred) {
 313			err = -EOPNOTSUPP;
 314			goto done;
 315		}
 316		break;
 317	case L2CAP_MODE_ERTM:
 318	case L2CAP_MODE_STREAMING:
 319		if (!disable_ertm)
 320			break;
 321		fallthrough;
 322	default:
 323		err = -EOPNOTSUPP;
 324		goto done;
 325	}
 326
 327	l2cap_sock_init_pid(sk);
 328
 329	sk->sk_max_ack_backlog = backlog;
 330	sk->sk_ack_backlog = 0;
 331
 332	/* Listening channels need to use nested locking in order not to
 333	 * cause lockdep warnings when the created child channels end up
 334	 * being locked in the same thread as the parent channel.
 335	 */
 336	atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
 337
 338	chan->state = BT_LISTEN;
 339	sk->sk_state = BT_LISTEN;
 340
 341done:
 342	release_sock(sk);
 343	return err;
 344}
 345
 346static int l2cap_sock_accept(struct socket *sock, struct socket *newsock,
 347			     int flags, bool kern)
 348{
 349	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 350	struct sock *sk = sock->sk, *nsk;
 351	long timeo;
 352	int err = 0;
 353
 354	lock_sock_nested(sk, L2CAP_NESTING_PARENT);
 355
 356	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 357
 358	BT_DBG("sk %p timeo %ld", sk, timeo);
 359
 360	/* Wait for an incoming connection. (wake-one). */
 361	add_wait_queue_exclusive(sk_sleep(sk), &wait);
 362	while (1) {
 363		if (sk->sk_state != BT_LISTEN) {
 364			err = -EBADFD;
 365			break;
 366		}
 367
 368		nsk = bt_accept_dequeue(sk, newsock);
 369		if (nsk)
 370			break;
 371
 372		if (!timeo) {
 373			err = -EAGAIN;
 374			break;
 375		}
 376
 377		if (signal_pending(current)) {
 378			err = sock_intr_errno(timeo);
 379			break;
 380		}
 381
 382		release_sock(sk);
 383
 384		timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
 385
 386		lock_sock_nested(sk, L2CAP_NESTING_PARENT);
 387	}
 388	remove_wait_queue(sk_sleep(sk), &wait);
 389
 390	if (err)
 391		goto done;
 392
 393	newsock->state = SS_CONNECTED;
 394
 395	BT_DBG("new socket %p", nsk);
 396
 397done:
 398	release_sock(sk);
 399	return err;
 400}
 401
 402static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr,
 403			      int peer)
 404{
 405	struct sockaddr_l2 *la = (struct sockaddr_l2 *) addr;
 406	struct sock *sk = sock->sk;
 407	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 408
 409	BT_DBG("sock %p, sk %p", sock, sk);
 410
 411	if (peer && sk->sk_state != BT_CONNECTED &&
 412	    sk->sk_state != BT_CONNECT && sk->sk_state != BT_CONNECT2 &&
 413	    sk->sk_state != BT_CONFIG)
 414		return -ENOTCONN;
 415
 416	memset(la, 0, sizeof(struct sockaddr_l2));
 417	addr->sa_family = AF_BLUETOOTH;
 418
 419	la->l2_psm = chan->psm;
 420
 421	if (peer) {
 422		bacpy(&la->l2_bdaddr, &chan->dst);
 423		la->l2_cid = cpu_to_le16(chan->dcid);
 424		la->l2_bdaddr_type = chan->dst_type;
 425	} else {
 426		bacpy(&la->l2_bdaddr, &chan->src);
 427		la->l2_cid = cpu_to_le16(chan->scid);
 428		la->l2_bdaddr_type = chan->src_type;
 429	}
 430
 431	return sizeof(struct sockaddr_l2);
 432}
 433
 434static int l2cap_get_mode(struct l2cap_chan *chan)
 435{
 436	switch (chan->mode) {
 437	case L2CAP_MODE_BASIC:
 438		return BT_MODE_BASIC;
 439	case L2CAP_MODE_ERTM:
 440		return BT_MODE_ERTM;
 441	case L2CAP_MODE_STREAMING:
 442		return BT_MODE_STREAMING;
 443	case L2CAP_MODE_LE_FLOWCTL:
 444		return BT_MODE_LE_FLOWCTL;
 445	case L2CAP_MODE_EXT_FLOWCTL:
 446		return BT_MODE_EXT_FLOWCTL;
 447	}
 448
 449	return -EINVAL;
 450}
 451
 452static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
 453				     char __user *optval, int __user *optlen)
 454{
 455	struct sock *sk = sock->sk;
 456	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 457	struct l2cap_options opts;
 458	struct l2cap_conninfo cinfo;
 459	int len, err = 0;
 460	u32 opt;
 461
 462	BT_DBG("sk %p", sk);
 463
 464	if (get_user(len, optlen))
 465		return -EFAULT;
 466
 467	lock_sock(sk);
 468
 469	switch (optname) {
 470	case L2CAP_OPTIONS:
 471		/* LE sockets should use BT_SNDMTU/BT_RCVMTU, but since
 472		 * legacy ATT code depends on getsockopt for
 473		 * L2CAP_OPTIONS we need to let this pass.
 474		 */
 475		if (bdaddr_type_is_le(chan->src_type) &&
 476		    chan->scid != L2CAP_CID_ATT) {
 477			err = -EINVAL;
 478			break;
 479		}
 480
 481		/* Only BR/EDR modes are supported here */
 482		switch (chan->mode) {
 483		case L2CAP_MODE_BASIC:
 484		case L2CAP_MODE_ERTM:
 485		case L2CAP_MODE_STREAMING:
 486			break;
 487		default:
 488			err = -EINVAL;
 489			break;
 490		}
 491
 492		if (err < 0)
 493			break;
 494
 495		memset(&opts, 0, sizeof(opts));
 496		opts.imtu     = chan->imtu;
 497		opts.omtu     = chan->omtu;
 498		opts.flush_to = chan->flush_to;
 499		opts.mode     = chan->mode;
 500		opts.fcs      = chan->fcs;
 501		opts.max_tx   = chan->max_tx;
 502		opts.txwin_size = chan->tx_win;
 503
 504		BT_DBG("mode 0x%2.2x", chan->mode);
 505
 506		len = min_t(unsigned int, len, sizeof(opts));
 507		if (copy_to_user(optval, (char *) &opts, len))
 508			err = -EFAULT;
 509
 510		break;
 511
 512	case L2CAP_LM:
 513		switch (chan->sec_level) {
 514		case BT_SECURITY_LOW:
 515			opt = L2CAP_LM_AUTH;
 516			break;
 517		case BT_SECURITY_MEDIUM:
 518			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT;
 519			break;
 520		case BT_SECURITY_HIGH:
 521			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
 522			      L2CAP_LM_SECURE;
 523			break;
 524		case BT_SECURITY_FIPS:
 525			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
 526			      L2CAP_LM_SECURE | L2CAP_LM_FIPS;
 527			break;
 528		default:
 529			opt = 0;
 530			break;
 531		}
 532
 533		if (test_bit(FLAG_ROLE_SWITCH, &chan->flags))
 534			opt |= L2CAP_LM_MASTER;
 535
 536		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
 537			opt |= L2CAP_LM_RELIABLE;
 538
 539		if (put_user(opt, (u32 __user *) optval))
 540			err = -EFAULT;
 541
 542		break;
 543
 544	case L2CAP_CONNINFO:
 545		if (sk->sk_state != BT_CONNECTED &&
 546		    !(sk->sk_state == BT_CONNECT2 &&
 547		      test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))) {
 548			err = -ENOTCONN;
 549			break;
 550		}
 551
 552		memset(&cinfo, 0, sizeof(cinfo));
 553		cinfo.hci_handle = chan->conn->hcon->handle;
 554		memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3);
 555
 556		len = min_t(unsigned int, len, sizeof(cinfo));
 557		if (copy_to_user(optval, (char *) &cinfo, len))
 558			err = -EFAULT;
 559
 560		break;
 561
 562	default:
 563		err = -ENOPROTOOPT;
 564		break;
 565	}
 566
 567	release_sock(sk);
 568	return err;
 569}
 570
 571static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
 572				 char __user *optval, int __user *optlen)
 573{
 574	struct sock *sk = sock->sk;
 575	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 576	struct bt_security sec;
 577	struct bt_power pwr;
 578	u32 phys;
 579	int len, mode, err = 0;
 580
 581	BT_DBG("sk %p", sk);
 582
 583	if (level == SOL_L2CAP)
 584		return l2cap_sock_getsockopt_old(sock, optname, optval, optlen);
 585
 586	if (level != SOL_BLUETOOTH)
 587		return -ENOPROTOOPT;
 588
 589	if (get_user(len, optlen))
 590		return -EFAULT;
 591
 592	lock_sock(sk);
 593
 594	switch (optname) {
 595	case BT_SECURITY:
 596		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
 597		    chan->chan_type != L2CAP_CHAN_FIXED &&
 598		    chan->chan_type != L2CAP_CHAN_RAW) {
 599			err = -EINVAL;
 600			break;
 601		}
 602
 603		memset(&sec, 0, sizeof(sec));
 604		if (chan->conn) {
 605			sec.level = chan->conn->hcon->sec_level;
 606
 607			if (sk->sk_state == BT_CONNECTED)
 608				sec.key_size = chan->conn->hcon->enc_key_size;
 609		} else {
 610			sec.level = chan->sec_level;
 611		}
 612
 613		len = min_t(unsigned int, len, sizeof(sec));
 614		if (copy_to_user(optval, (char *) &sec, len))
 615			err = -EFAULT;
 616
 617		break;
 618
 619	case BT_DEFER_SETUP:
 620		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
 621			err = -EINVAL;
 622			break;
 623		}
 624
 625		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
 626			     (u32 __user *) optval))
 627			err = -EFAULT;
 628
 629		break;
 630
 631	case BT_FLUSHABLE:
 632		if (put_user(test_bit(FLAG_FLUSHABLE, &chan->flags),
 633			     (u32 __user *) optval))
 634			err = -EFAULT;
 635
 636		break;
 637
 638	case BT_POWER:
 639		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
 640		    && sk->sk_type != SOCK_RAW) {
 641			err = -EINVAL;
 642			break;
 643		}
 644
 645		pwr.force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 646
 647		len = min_t(unsigned int, len, sizeof(pwr));
 648		if (copy_to_user(optval, (char *) &pwr, len))
 649			err = -EFAULT;
 650
 651		break;
 652
 653	case BT_CHANNEL_POLICY:
 654		if (put_user(chan->chan_policy, (u32 __user *) optval))
 655			err = -EFAULT;
 656		break;
 657
 658	case BT_SNDMTU:
 659		if (!bdaddr_type_is_le(chan->src_type)) {
 660			err = -EINVAL;
 661			break;
 662		}
 663
 664		if (sk->sk_state != BT_CONNECTED) {
 665			err = -ENOTCONN;
 666			break;
 667		}
 668
 669		if (put_user(chan->omtu, (u16 __user *) optval))
 670			err = -EFAULT;
 671		break;
 672
 673	case BT_RCVMTU:
 674		if (!bdaddr_type_is_le(chan->src_type)) {
 675			err = -EINVAL;
 676			break;
 677		}
 678
 679		if (put_user(chan->imtu, (u16 __user *) optval))
 680			err = -EFAULT;
 681		break;
 682
 683	case BT_PHY:
 684		if (sk->sk_state != BT_CONNECTED) {
 685			err = -ENOTCONN;
 686			break;
 687		}
 688
 689		phys = hci_conn_get_phy(chan->conn->hcon);
 690
 691		if (put_user(phys, (u32 __user *) optval))
 692			err = -EFAULT;
 693		break;
 694
 695	case BT_MODE:
 696		if (!enable_ecred) {
 697			err = -ENOPROTOOPT;
 698			break;
 699		}
 700
 701		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
 702			err = -EINVAL;
 703			break;
 704		}
 705
 706		mode = l2cap_get_mode(chan);
 707		if (mode < 0) {
 708			err = mode;
 709			break;
 710		}
 711
 712		if (put_user(mode, (u8 __user *) optval))
 713			err = -EFAULT;
 714		break;
 715
 716	default:
 717		err = -ENOPROTOOPT;
 718		break;
 719	}
 720
 721	release_sock(sk);
 722	return err;
 723}
 724
 725static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu)
 726{
 727	switch (chan->scid) {
 728	case L2CAP_CID_ATT:
 729		if (mtu < L2CAP_LE_MIN_MTU)
 730			return false;
 731		break;
 732
 733	default:
 734		if (mtu < L2CAP_DEFAULT_MIN_MTU)
 735			return false;
 736	}
 737
 738	return true;
 739}
 740
 741static int l2cap_sock_setsockopt_old(struct socket *sock, int optname,
 742				     sockptr_t optval, unsigned int optlen)
 743{
 744	struct sock *sk = sock->sk;
 745	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 746	struct l2cap_options opts;
 747	int len, err = 0;
 748	u32 opt;
 749
 750	BT_DBG("sk %p", sk);
 751
 752	lock_sock(sk);
 753
 754	switch (optname) {
 755	case L2CAP_OPTIONS:
 756		if (bdaddr_type_is_le(chan->src_type)) {
 757			err = -EINVAL;
 758			break;
 759		}
 760
 761		if (sk->sk_state == BT_CONNECTED) {
 762			err = -EINVAL;
 763			break;
 764		}
 765
 766		opts.imtu     = chan->imtu;
 767		opts.omtu     = chan->omtu;
 768		opts.flush_to = chan->flush_to;
 769		opts.mode     = chan->mode;
 770		opts.fcs      = chan->fcs;
 771		opts.max_tx   = chan->max_tx;
 772		opts.txwin_size = chan->tx_win;
 773
 774		len = min_t(unsigned int, sizeof(opts), optlen);
 775		if (copy_from_sockptr(&opts, optval, len)) {
 776			err = -EFAULT;
 777			break;
 778		}
 779
 780		if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) {
 781			err = -EINVAL;
 782			break;
 783		}
 784
 785		if (!l2cap_valid_mtu(chan, opts.imtu)) {
 786			err = -EINVAL;
 787			break;
 788		}
 789
 790		/* Only BR/EDR modes are supported here */
 791		switch (opts.mode) {
 792		case L2CAP_MODE_BASIC:
 793			clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
 794			break;
 795		case L2CAP_MODE_ERTM:
 796		case L2CAP_MODE_STREAMING:
 797			if (!disable_ertm)
 798				break;
 799			fallthrough;
 800		default:
 801			err = -EINVAL;
 802			break;
 803		}
 804
 805		if (err < 0)
 806			break;
 807
 808		chan->mode = opts.mode;
 809
 810		BT_DBG("mode 0x%2.2x", chan->mode);
 811
 812		chan->imtu = opts.imtu;
 813		chan->omtu = opts.omtu;
 814		chan->fcs  = opts.fcs;
 815		chan->max_tx = opts.max_tx;
 816		chan->tx_win = opts.txwin_size;
 817		chan->flush_to = opts.flush_to;
 818		break;
 819
 820	case L2CAP_LM:
 821		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
 822			err = -EFAULT;
 823			break;
 824		}
 825
 826		if (opt & L2CAP_LM_FIPS) {
 827			err = -EINVAL;
 828			break;
 829		}
 830
 831		if (opt & L2CAP_LM_AUTH)
 832			chan->sec_level = BT_SECURITY_LOW;
 833		if (opt & L2CAP_LM_ENCRYPT)
 834			chan->sec_level = BT_SECURITY_MEDIUM;
 835		if (opt & L2CAP_LM_SECURE)
 836			chan->sec_level = BT_SECURITY_HIGH;
 837
 838		if (opt & L2CAP_LM_MASTER)
 839			set_bit(FLAG_ROLE_SWITCH, &chan->flags);
 840		else
 841			clear_bit(FLAG_ROLE_SWITCH, &chan->flags);
 842
 843		if (opt & L2CAP_LM_RELIABLE)
 844			set_bit(FLAG_FORCE_RELIABLE, &chan->flags);
 845		else
 846			clear_bit(FLAG_FORCE_RELIABLE, &chan->flags);
 847		break;
 848
 849	default:
 850		err = -ENOPROTOOPT;
 851		break;
 852	}
 853
 854	release_sock(sk);
 855	return err;
 856}
 857
 858static int l2cap_set_mode(struct l2cap_chan *chan, u8 mode)
 859{
 860	switch (mode) {
 861	case BT_MODE_BASIC:
 862		if (bdaddr_type_is_le(chan->src_type))
 863			return -EINVAL;
 864		mode = L2CAP_MODE_BASIC;
 865		clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
 866		break;
 867	case BT_MODE_ERTM:
 868		if (!disable_ertm || bdaddr_type_is_le(chan->src_type))
 869			return -EINVAL;
 870		mode = L2CAP_MODE_ERTM;
 871		break;
 872	case BT_MODE_STREAMING:
 873		if (!disable_ertm || bdaddr_type_is_le(chan->src_type))
 874			return -EINVAL;
 875		mode = L2CAP_MODE_STREAMING;
 876		break;
 877	case BT_MODE_LE_FLOWCTL:
 878		if (!bdaddr_type_is_le(chan->src_type))
 879			return -EINVAL;
 880		mode = L2CAP_MODE_LE_FLOWCTL;
 881		break;
 882	case BT_MODE_EXT_FLOWCTL:
 883		/* TODO: Add support for ECRED PDUs to BR/EDR */
 884		if (!bdaddr_type_is_le(chan->src_type))
 885			return -EINVAL;
 886		mode = L2CAP_MODE_EXT_FLOWCTL;
 887		break;
 888	default:
 889		return -EINVAL;
 890	}
 891
 892	chan->mode = mode;
 893
 894	return 0;
 895}
 896
 897static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname,
 898				 sockptr_t optval, unsigned int optlen)
 899{
 900	struct sock *sk = sock->sk;
 901	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
 902	struct bt_security sec;
 903	struct bt_power pwr;
 904	struct l2cap_conn *conn;
 905	int len, err = 0;
 906	u32 opt;
 907	u16 mtu;
 908	u8 mode;
 909
 910	BT_DBG("sk %p", sk);
 911
 912	if (level == SOL_L2CAP)
 913		return l2cap_sock_setsockopt_old(sock, optname, optval, optlen);
 914
 915	if (level != SOL_BLUETOOTH)
 916		return -ENOPROTOOPT;
 917
 918	lock_sock(sk);
 919
 920	switch (optname) {
 921	case BT_SECURITY:
 922		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
 923		    chan->chan_type != L2CAP_CHAN_FIXED &&
 924		    chan->chan_type != L2CAP_CHAN_RAW) {
 925			err = -EINVAL;
 926			break;
 927		}
 928
 929		sec.level = BT_SECURITY_LOW;
 930
 931		len = min_t(unsigned int, sizeof(sec), optlen);
 932		if (copy_from_sockptr(&sec, optval, len)) {
 933			err = -EFAULT;
 934			break;
 935		}
 936
 937		if (sec.level < BT_SECURITY_LOW ||
 938		    sec.level > BT_SECURITY_FIPS) {
 939			err = -EINVAL;
 940			break;
 941		}
 942
 943		chan->sec_level = sec.level;
 944
 945		if (!chan->conn)
 946			break;
 947
 948		conn = chan->conn;
 949
 950		/* change security for LE channels */
 951		if (chan->scid == L2CAP_CID_ATT) {
 952			if (smp_conn_security(conn->hcon, sec.level)) {
 953				err = -EINVAL;
 954				break;
 955			}
 956
 957			set_bit(FLAG_PENDING_SECURITY, &chan->flags);
 958			sk->sk_state = BT_CONFIG;
 959			chan->state = BT_CONFIG;
 960
 961		/* or for ACL link */
 962		} else if ((sk->sk_state == BT_CONNECT2 &&
 963			    test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) ||
 964			   sk->sk_state == BT_CONNECTED) {
 965			if (!l2cap_chan_check_security(chan, true))
 966				set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
 967			else
 968				sk->sk_state_change(sk);
 969		} else {
 970			err = -EINVAL;
 971		}
 972		break;
 973
 974	case BT_DEFER_SETUP:
 975		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
 976			err = -EINVAL;
 977			break;
 978		}
 979
 980		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
 981			err = -EFAULT;
 982			break;
 983		}
 984
 985		if (opt) {
 986			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
 987			set_bit(FLAG_DEFER_SETUP, &chan->flags);
 988		} else {
 989			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
 990			clear_bit(FLAG_DEFER_SETUP, &chan->flags);
 991		}
 992		break;
 993
 994	case BT_FLUSHABLE:
 995		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
 996			err = -EFAULT;
 997			break;
 998		}
 999
1000		if (opt > BT_FLUSHABLE_ON) {
1001			err = -EINVAL;
1002			break;
1003		}
1004
1005		if (opt == BT_FLUSHABLE_OFF) {
1006			conn = chan->conn;
1007			/* proceed further only when we have l2cap_conn and
1008			   No Flush support in the LM */
1009			if (!conn || !lmp_no_flush_capable(conn->hcon->hdev)) {
1010				err = -EINVAL;
1011				break;
1012			}
1013		}
1014
1015		if (opt)
1016			set_bit(FLAG_FLUSHABLE, &chan->flags);
1017		else
1018			clear_bit(FLAG_FLUSHABLE, &chan->flags);
1019		break;
1020
1021	case BT_POWER:
1022		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
1023		    chan->chan_type != L2CAP_CHAN_RAW) {
1024			err = -EINVAL;
1025			break;
1026		}
1027
1028		pwr.force_active = BT_POWER_FORCE_ACTIVE_ON;
1029
1030		len = min_t(unsigned int, sizeof(pwr), optlen);
1031		if (copy_from_sockptr(&pwr, optval, len)) {
1032			err = -EFAULT;
1033			break;
1034		}
1035
1036		if (pwr.force_active)
1037			set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
1038		else
1039			clear_bit(FLAG_FORCE_ACTIVE, &chan->flags);
1040		break;
1041
1042	case BT_CHANNEL_POLICY:
1043		if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
1044			err = -EFAULT;
1045			break;
1046		}
1047
1048		if (opt > BT_CHANNEL_POLICY_AMP_PREFERRED) {
1049			err = -EINVAL;
1050			break;
1051		}
1052
1053		if (chan->mode != L2CAP_MODE_ERTM &&
1054		    chan->mode != L2CAP_MODE_STREAMING) {
1055			err = -EOPNOTSUPP;
1056			break;
1057		}
1058
1059		chan->chan_policy = (u8) opt;
1060
1061		if (sk->sk_state == BT_CONNECTED &&
1062		    chan->move_role == L2CAP_MOVE_ROLE_NONE)
1063			l2cap_move_start(chan);
1064
1065		break;
1066
1067	case BT_SNDMTU:
1068		if (!bdaddr_type_is_le(chan->src_type)) {
1069			err = -EINVAL;
1070			break;
1071		}
1072
1073		/* Setting is not supported as it's the remote side that
1074		 * decides this.
1075		 */
1076		err = -EPERM;
1077		break;
1078
1079	case BT_RCVMTU:
1080		if (!bdaddr_type_is_le(chan->src_type)) {
1081			err = -EINVAL;
1082			break;
1083		}
1084
1085		if (chan->mode == L2CAP_MODE_LE_FLOWCTL &&
1086		    sk->sk_state == BT_CONNECTED) {
1087			err = -EISCONN;
1088			break;
1089		}
1090
1091		if (copy_from_sockptr(&mtu, optval, sizeof(u16))) {
1092			err = -EFAULT;
1093			break;
1094		}
1095
1096		if (chan->mode == L2CAP_MODE_EXT_FLOWCTL &&
1097		    sk->sk_state == BT_CONNECTED)
1098			err = l2cap_chan_reconfigure(chan, mtu);
1099		else
1100			chan->imtu = mtu;
1101
1102		break;
1103
1104	case BT_MODE:
1105		if (!enable_ecred) {
1106			err = -ENOPROTOOPT;
1107			break;
1108		}
1109
1110		BT_DBG("sk->sk_state %u", sk->sk_state);
1111
1112		if (sk->sk_state != BT_BOUND) {
1113			err = -EINVAL;
1114			break;
1115		}
1116
1117		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1118			err = -EINVAL;
1119			break;
1120		}
1121
1122		if (copy_from_sockptr(&mode, optval, sizeof(u8))) {
1123			err = -EFAULT;
1124			break;
1125		}
1126
1127		BT_DBG("mode %u", mode);
1128
1129		err = l2cap_set_mode(chan, mode);
1130		if (err)
1131			break;
1132
1133		BT_DBG("mode 0x%2.2x", chan->mode);
1134
1135		break;
1136
1137	default:
1138		err = -ENOPROTOOPT;
1139		break;
1140	}
1141
1142	release_sock(sk);
1143	return err;
1144}
1145
1146static int l2cap_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1147			      size_t len)
1148{
1149	struct sock *sk = sock->sk;
1150	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1151	int err;
1152
1153	BT_DBG("sock %p, sk %p", sock, sk);
1154
1155	err = sock_error(sk);
1156	if (err)
1157		return err;
1158
1159	if (msg->msg_flags & MSG_OOB)
1160		return -EOPNOTSUPP;
1161
1162	if (sk->sk_state != BT_CONNECTED)
1163		return -ENOTCONN;
1164
1165	lock_sock(sk);
1166	err = bt_sock_wait_ready(sk, msg->msg_flags);
1167	release_sock(sk);
1168	if (err)
1169		return err;
1170
1171	l2cap_chan_lock(chan);
1172	err = l2cap_chan_send(chan, msg, len);
1173	l2cap_chan_unlock(chan);
1174
1175	return err;
1176}
1177
1178static int l2cap_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1179			      size_t len, int flags)
1180{
1181	struct sock *sk = sock->sk;
1182	struct l2cap_pinfo *pi = l2cap_pi(sk);
1183	int err;
1184
1185	lock_sock(sk);
1186
1187	if (sk->sk_state == BT_CONNECT2 && test_bit(BT_SK_DEFER_SETUP,
1188						    &bt_sk(sk)->flags)) {
1189		if (pi->chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
1190			sk->sk_state = BT_CONNECTED;
1191			pi->chan->state = BT_CONNECTED;
1192			__l2cap_ecred_conn_rsp_defer(pi->chan);
1193		} else if (bdaddr_type_is_le(pi->chan->src_type)) {
1194			sk->sk_state = BT_CONNECTED;
1195			pi->chan->state = BT_CONNECTED;
1196			__l2cap_le_connect_rsp_defer(pi->chan);
1197		} else {
1198			sk->sk_state = BT_CONFIG;
1199			pi->chan->state = BT_CONFIG;
1200			__l2cap_connect_rsp_defer(pi->chan);
1201		}
1202
1203		err = 0;
1204		goto done;
1205	}
1206
1207	release_sock(sk);
1208
1209	if (sock->type == SOCK_STREAM)
1210		err = bt_sock_stream_recvmsg(sock, msg, len, flags);
1211	else
1212		err = bt_sock_recvmsg(sock, msg, len, flags);
1213
1214	if (pi->chan->mode != L2CAP_MODE_ERTM)
1215		return err;
1216
1217	/* Attempt to put pending rx data in the socket buffer */
1218
1219	lock_sock(sk);
1220
1221	if (!test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state))
1222		goto done;
1223
1224	if (pi->rx_busy_skb) {
1225		if (!__sock_queue_rcv_skb(sk, pi->rx_busy_skb))
1226			pi->rx_busy_skb = NULL;
1227		else
1228			goto done;
1229	}
1230
1231	/* Restore data flow when half of the receive buffer is
1232	 * available.  This avoids resending large numbers of
1233	 * frames.
1234	 */
1235	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1)
1236		l2cap_chan_busy(pi->chan, 0);
1237
1238done:
1239	release_sock(sk);
1240	return err;
1241}
1242
1243/* Kill socket (only if zapped and orphan)
1244 * Must be called on unlocked socket, with l2cap channel lock.
1245 */
1246static void l2cap_sock_kill(struct sock *sk)
1247{
1248	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
1249		return;
1250
1251	BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state));
1252
1253	/* Kill poor orphan */
1254
1255	l2cap_chan_put(l2cap_pi(sk)->chan);
1256	sock_set_flag(sk, SOCK_DEAD);
1257	sock_put(sk);
1258}
1259
1260static int __l2cap_wait_ack(struct sock *sk, struct l2cap_chan *chan)
1261{
1262	DECLARE_WAITQUEUE(wait, current);
1263	int err = 0;
1264	int timeo = L2CAP_WAIT_ACK_POLL_PERIOD;
1265	/* Timeout to prevent infinite loop */
1266	unsigned long timeout = jiffies + L2CAP_WAIT_ACK_TIMEOUT;
1267
1268	add_wait_queue(sk_sleep(sk), &wait);
1269	set_current_state(TASK_INTERRUPTIBLE);
1270	do {
1271		BT_DBG("Waiting for %d ACKs, timeout %04d ms",
1272		       chan->unacked_frames, time_after(jiffies, timeout) ? 0 :
1273		       jiffies_to_msecs(timeout - jiffies));
1274
1275		if (!timeo)
1276			timeo = L2CAP_WAIT_ACK_POLL_PERIOD;
1277
1278		if (signal_pending(current)) {
1279			err = sock_intr_errno(timeo);
1280			break;
1281		}
1282
1283		release_sock(sk);
1284		timeo = schedule_timeout(timeo);
1285		lock_sock(sk);
1286		set_current_state(TASK_INTERRUPTIBLE);
1287
1288		err = sock_error(sk);
1289		if (err)
1290			break;
1291
1292		if (time_after(jiffies, timeout)) {
1293			err = -ENOLINK;
1294			break;
1295		}
1296
1297	} while (chan->unacked_frames > 0 &&
1298		 chan->state == BT_CONNECTED);
1299
1300	set_current_state(TASK_RUNNING);
1301	remove_wait_queue(sk_sleep(sk), &wait);
1302	return err;
1303}
1304
1305static int l2cap_sock_shutdown(struct socket *sock, int how)
1306{
1307	struct sock *sk = sock->sk;
1308	struct l2cap_chan *chan;
1309	struct l2cap_conn *conn;
1310	int err = 0;
1311
1312	BT_DBG("sock %p, sk %p, how %d", sock, sk, how);
1313
1314	/* 'how' parameter is mapped to sk_shutdown as follows:
1315	 * SHUT_RD   (0) --> RCV_SHUTDOWN  (1)
1316	 * SHUT_WR   (1) --> SEND_SHUTDOWN (2)
1317	 * SHUT_RDWR (2) --> SHUTDOWN_MASK (3)
1318	 */
1319	how++;
1320
1321	if (!sk)
1322		return 0;
1323
1324	lock_sock(sk);
1325
1326	if ((sk->sk_shutdown & how) == how)
1327		goto shutdown_already;
1328
1329	BT_DBG("Handling sock shutdown");
1330
1331	/* prevent sk structure from being freed whilst unlocked */
1332	sock_hold(sk);
1333
1334	chan = l2cap_pi(sk)->chan;
1335	/* prevent chan structure from being freed whilst unlocked */
1336	l2cap_chan_hold(chan);
1337
1338	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
1339
1340	if (chan->mode == L2CAP_MODE_ERTM &&
1341	    chan->unacked_frames > 0 &&
1342	    chan->state == BT_CONNECTED) {
1343		err = __l2cap_wait_ack(sk, chan);
1344
1345		/* After waiting for ACKs, check whether shutdown
1346		 * has already been actioned to close the L2CAP
1347		 * link such as by l2cap_disconnection_req().
1348		 */
1349		if ((sk->sk_shutdown & how) == how)
1350			goto shutdown_matched;
1351	}
1352
1353	/* Try setting the RCV_SHUTDOWN bit, return early if SEND_SHUTDOWN
1354	 * is already set
1355	 */
1356	if ((how & RCV_SHUTDOWN) && !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1357		sk->sk_shutdown |= RCV_SHUTDOWN;
1358		if ((sk->sk_shutdown & how) == how)
1359			goto shutdown_matched;
1360	}
1361
1362	sk->sk_shutdown |= SEND_SHUTDOWN;
1363	release_sock(sk);
1364
1365	l2cap_chan_lock(chan);
1366	conn = chan->conn;
1367	if (conn)
1368		/* prevent conn structure from being freed */
1369		l2cap_conn_get(conn);
1370	l2cap_chan_unlock(chan);
1371
1372	if (conn)
1373		/* mutex lock must be taken before l2cap_chan_lock() */
1374		mutex_lock(&conn->chan_lock);
1375
1376	l2cap_chan_lock(chan);
1377	l2cap_chan_close(chan, 0);
1378	l2cap_chan_unlock(chan);
1379
1380	if (conn) {
1381		mutex_unlock(&conn->chan_lock);
1382		l2cap_conn_put(conn);
1383	}
1384
1385	lock_sock(sk);
1386
1387	if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime &&
1388	    !(current->flags & PF_EXITING))
1389		err = bt_sock_wait_state(sk, BT_CLOSED,
1390					 sk->sk_lingertime);
1391
1392shutdown_matched:
1393	l2cap_chan_put(chan);
1394	sock_put(sk);
1395
1396shutdown_already:
1397	if (!err && sk->sk_err)
1398		err = -sk->sk_err;
1399
1400	release_sock(sk);
1401
1402	BT_DBG("Sock shutdown complete err: %d", err);
1403
1404	return err;
1405}
1406
1407static int l2cap_sock_release(struct socket *sock)
1408{
1409	struct sock *sk = sock->sk;
1410	int err;
1411	struct l2cap_chan *chan;
1412
1413	BT_DBG("sock %p, sk %p", sock, sk);
1414
1415	if (!sk)
1416		return 0;
1417
 
1418	bt_sock_unlink(&l2cap_sk_list, sk);
1419
1420	err = l2cap_sock_shutdown(sock, SHUT_RDWR);
1421	chan = l2cap_pi(sk)->chan;
1422
1423	l2cap_chan_hold(chan);
1424	l2cap_chan_lock(chan);
1425
1426	sock_orphan(sk);
1427	l2cap_sock_kill(sk);
1428
1429	l2cap_chan_unlock(chan);
1430	l2cap_chan_put(chan);
1431
1432	return err;
1433}
1434
1435static void l2cap_sock_cleanup_listen(struct sock *parent)
1436{
1437	struct sock *sk;
1438
1439	BT_DBG("parent %p state %s", parent,
1440	       state_to_string(parent->sk_state));
1441
1442	/* Close not yet accepted channels */
1443	while ((sk = bt_accept_dequeue(parent, NULL))) {
1444		struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1445
1446		BT_DBG("child chan %p state %s", chan,
1447		       state_to_string(chan->state));
1448
1449		l2cap_chan_hold(chan);
1450		l2cap_chan_lock(chan);
1451
1452		__clear_chan_timer(chan);
1453		l2cap_chan_close(chan, ECONNRESET);
1454		l2cap_sock_kill(sk);
1455
1456		l2cap_chan_unlock(chan);
1457		l2cap_chan_put(chan);
1458	}
1459}
1460
1461static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
1462{
1463	struct sock *sk, *parent = chan->data;
1464
1465	lock_sock(parent);
1466
1467	/* Check for backlog size */
1468	if (sk_acceptq_is_full(parent)) {
1469		BT_DBG("backlog full %d", parent->sk_ack_backlog);
1470		release_sock(parent);
1471		return NULL;
1472	}
1473
1474	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP,
1475			      GFP_ATOMIC, 0);
1476	if (!sk) {
1477		release_sock(parent);
1478		return NULL;
1479        }
1480
1481	bt_sock_reclassify_lock(sk, BTPROTO_L2CAP);
1482
1483	l2cap_sock_init(sk, parent);
1484
1485	bt_accept_enqueue(parent, sk, false);
1486
1487	release_sock(parent);
1488
1489	return l2cap_pi(sk)->chan;
1490}
1491
1492static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
1493{
1494	struct sock *sk = chan->data;
1495	int err;
1496
1497	lock_sock(sk);
1498
1499	if (l2cap_pi(sk)->rx_busy_skb) {
1500		err = -ENOMEM;
1501		goto done;
1502	}
1503
1504	if (chan->mode != L2CAP_MODE_ERTM &&
1505	    chan->mode != L2CAP_MODE_STREAMING) {
1506		/* Even if no filter is attached, we could potentially
1507		 * get errors from security modules, etc.
1508		 */
1509		err = sk_filter(sk, skb);
1510		if (err)
1511			goto done;
1512	}
1513
1514	err = __sock_queue_rcv_skb(sk, skb);
1515
1516	/* For ERTM, handle one skb that doesn't fit into the recv
1517	 * buffer.  This is important to do because the data frames
1518	 * have already been acked, so the skb cannot be discarded.
1519	 *
1520	 * Notify the l2cap core that the buffer is full, so the
1521	 * LOCAL_BUSY state is entered and no more frames are
1522	 * acked and reassembled until there is buffer space
1523	 * available.
1524	 */
1525	if (err < 0 && chan->mode == L2CAP_MODE_ERTM) {
1526		l2cap_pi(sk)->rx_busy_skb = skb;
1527		l2cap_chan_busy(chan, 1);
1528		err = 0;
1529	}
1530
1531done:
1532	release_sock(sk);
1533
1534	return err;
1535}
1536
1537static void l2cap_sock_close_cb(struct l2cap_chan *chan)
1538{
1539	struct sock *sk = chan->data;
1540
1541	if (!sk)
1542		return;
1543
1544	l2cap_sock_kill(sk);
1545}
1546
1547static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err)
1548{
1549	struct sock *sk = chan->data;
1550	struct sock *parent;
1551
1552	if (!sk)
1553		return;
1554
1555	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
1556
1557	/* This callback can be called both for server (BT_LISTEN)
1558	 * sockets as well as "normal" ones. To avoid lockdep warnings
1559	 * with child socket locking (through l2cap_sock_cleanup_listen)
1560	 * we need separation into separate nesting levels. The simplest
1561	 * way to accomplish this is to inherit the nesting level used
1562	 * for the channel.
1563	 */
1564	lock_sock_nested(sk, atomic_read(&chan->nesting));
1565
1566	parent = bt_sk(sk)->parent;
1567
1568	switch (chan->state) {
1569	case BT_OPEN:
1570	case BT_BOUND:
1571	case BT_CLOSED:
1572		break;
1573	case BT_LISTEN:
1574		l2cap_sock_cleanup_listen(sk);
1575		sk->sk_state = BT_CLOSED;
1576		chan->state = BT_CLOSED;
1577
1578		break;
1579	default:
1580		sk->sk_state = BT_CLOSED;
1581		chan->state = BT_CLOSED;
1582
1583		sk->sk_err = err;
1584
1585		if (parent) {
1586			bt_accept_unlink(sk);
1587			parent->sk_data_ready(parent);
1588		} else {
1589			sk->sk_state_change(sk);
1590		}
1591
1592		break;
1593	}
1594	release_sock(sk);
1595
1596	/* Only zap after cleanup to avoid use after free race */
1597	sock_set_flag(sk, SOCK_ZAPPED);
1598
1599}
1600
1601static void l2cap_sock_state_change_cb(struct l2cap_chan *chan, int state,
1602				       int err)
1603{
1604	struct sock *sk = chan->data;
1605
1606	sk->sk_state = state;
1607
1608	if (err)
1609		sk->sk_err = err;
1610}
1611
1612static struct sk_buff *l2cap_sock_alloc_skb_cb(struct l2cap_chan *chan,
1613					       unsigned long hdr_len,
1614					       unsigned long len, int nb)
1615{
1616	struct sock *sk = chan->data;
1617	struct sk_buff *skb;
1618	int err;
1619
1620	l2cap_chan_unlock(chan);
1621	skb = bt_skb_send_alloc(sk, hdr_len + len, nb, &err);
1622	l2cap_chan_lock(chan);
1623
1624	if (!skb)
1625		return ERR_PTR(err);
1626
1627	skb->priority = sk->sk_priority;
 
 
 
 
 
 
 
 
1628
1629	bt_cb(skb)->l2cap.chan = chan;
1630
1631	return skb;
1632}
1633
1634static void l2cap_sock_ready_cb(struct l2cap_chan *chan)
1635{
1636	struct sock *sk = chan->data;
1637	struct sock *parent;
1638
1639	lock_sock(sk);
1640
1641	parent = bt_sk(sk)->parent;
1642
1643	BT_DBG("sk %p, parent %p", sk, parent);
1644
1645	sk->sk_state = BT_CONNECTED;
1646	sk->sk_state_change(sk);
1647
1648	if (parent)
1649		parent->sk_data_ready(parent);
1650
1651	release_sock(sk);
1652}
1653
1654static void l2cap_sock_defer_cb(struct l2cap_chan *chan)
1655{
1656	struct sock *parent, *sk = chan->data;
1657
1658	lock_sock(sk);
1659
1660	parent = bt_sk(sk)->parent;
1661	if (parent)
1662		parent->sk_data_ready(parent);
1663
1664	release_sock(sk);
1665}
1666
1667static void l2cap_sock_resume_cb(struct l2cap_chan *chan)
1668{
1669	struct sock *sk = chan->data;
1670
1671	if (test_and_clear_bit(FLAG_PENDING_SECURITY, &chan->flags)) {
1672		sk->sk_state = BT_CONNECTED;
1673		chan->state = BT_CONNECTED;
1674	}
1675
1676	clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
1677	sk->sk_state_change(sk);
1678}
1679
1680static void l2cap_sock_set_shutdown_cb(struct l2cap_chan *chan)
1681{
1682	struct sock *sk = chan->data;
1683
1684	lock_sock(sk);
1685	sk->sk_shutdown = SHUTDOWN_MASK;
1686	release_sock(sk);
1687}
1688
1689static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan)
1690{
1691	struct sock *sk = chan->data;
1692
1693	return sk->sk_sndtimeo;
1694}
1695
1696static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan)
1697{
1698	struct sock *sk = chan->data;
1699
1700	return sk->sk_peer_pid;
1701}
1702
1703static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
1704{
1705	struct sock *sk = chan->data;
1706
1707	set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
1708	sk->sk_state_change(sk);
1709}
1710
1711static int l2cap_sock_filter(struct l2cap_chan *chan, struct sk_buff *skb)
1712{
1713	struct sock *sk = chan->data;
1714
1715	switch (chan->mode) {
1716	case L2CAP_MODE_ERTM:
1717	case L2CAP_MODE_STREAMING:
1718		return sk_filter(sk, skb);
1719	}
1720
1721	return 0;
1722}
1723
1724static const struct l2cap_ops l2cap_chan_ops = {
1725	.name			= "L2CAP Socket Interface",
1726	.new_connection		= l2cap_sock_new_connection_cb,
1727	.recv			= l2cap_sock_recv_cb,
1728	.close			= l2cap_sock_close_cb,
1729	.teardown		= l2cap_sock_teardown_cb,
1730	.state_change		= l2cap_sock_state_change_cb,
1731	.ready			= l2cap_sock_ready_cb,
1732	.defer			= l2cap_sock_defer_cb,
1733	.resume			= l2cap_sock_resume_cb,
1734	.suspend		= l2cap_sock_suspend_cb,
1735	.set_shutdown		= l2cap_sock_set_shutdown_cb,
1736	.get_sndtimeo		= l2cap_sock_get_sndtimeo_cb,
1737	.get_peer_pid		= l2cap_sock_get_peer_pid_cb,
1738	.alloc_skb		= l2cap_sock_alloc_skb_cb,
1739	.filter			= l2cap_sock_filter,
1740};
1741
1742static void l2cap_sock_destruct(struct sock *sk)
1743{
1744	BT_DBG("sk %p", sk);
1745
1746	if (l2cap_pi(sk)->chan) {
1747		l2cap_pi(sk)->chan->data = NULL;
1748		l2cap_chan_put(l2cap_pi(sk)->chan);
1749	}
1750
1751	if (l2cap_pi(sk)->rx_busy_skb) {
1752		kfree_skb(l2cap_pi(sk)->rx_busy_skb);
1753		l2cap_pi(sk)->rx_busy_skb = NULL;
1754	}
1755
1756	skb_queue_purge(&sk->sk_receive_queue);
1757	skb_queue_purge(&sk->sk_write_queue);
1758}
1759
1760static void l2cap_skb_msg_name(struct sk_buff *skb, void *msg_name,
1761			       int *msg_namelen)
1762{
1763	DECLARE_SOCKADDR(struct sockaddr_l2 *, la, msg_name);
1764
1765	memset(la, 0, sizeof(struct sockaddr_l2));
1766	la->l2_family = AF_BLUETOOTH;
1767	la->l2_psm = bt_cb(skb)->l2cap.psm;
1768	bacpy(&la->l2_bdaddr, &bt_cb(skb)->l2cap.bdaddr);
1769
1770	*msg_namelen = sizeof(struct sockaddr_l2);
1771}
1772
1773static void l2cap_sock_init(struct sock *sk, struct sock *parent)
1774{
1775	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1776
1777	BT_DBG("sk %p", sk);
1778
1779	if (parent) {
1780		struct l2cap_chan *pchan = l2cap_pi(parent)->chan;
1781
1782		sk->sk_type = parent->sk_type;
1783		bt_sk(sk)->flags = bt_sk(parent)->flags;
1784
1785		chan->chan_type = pchan->chan_type;
1786		chan->imtu = pchan->imtu;
1787		chan->omtu = pchan->omtu;
1788		chan->conf_state = pchan->conf_state;
1789		chan->mode = pchan->mode;
1790		chan->fcs  = pchan->fcs;
1791		chan->max_tx = pchan->max_tx;
1792		chan->tx_win = pchan->tx_win;
1793		chan->tx_win_max = pchan->tx_win_max;
1794		chan->sec_level = pchan->sec_level;
1795		chan->flags = pchan->flags;
1796		chan->tx_credits = pchan->tx_credits;
1797		chan->rx_credits = pchan->rx_credits;
1798
1799		if (chan->chan_type == L2CAP_CHAN_FIXED) {
1800			chan->scid = pchan->scid;
1801			chan->dcid = pchan->scid;
1802		}
1803
1804		security_sk_clone(parent, sk);
1805	} else {
1806		switch (sk->sk_type) {
1807		case SOCK_RAW:
1808			chan->chan_type = L2CAP_CHAN_RAW;
1809			break;
1810		case SOCK_DGRAM:
1811			chan->chan_type = L2CAP_CHAN_CONN_LESS;
1812			bt_sk(sk)->skb_msg_name = l2cap_skb_msg_name;
1813			break;
1814		case SOCK_SEQPACKET:
1815		case SOCK_STREAM:
1816			chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
1817			break;
1818		}
1819
1820		chan->imtu = L2CAP_DEFAULT_MTU;
1821		chan->omtu = 0;
1822		if (!disable_ertm && sk->sk_type == SOCK_STREAM) {
1823			chan->mode = L2CAP_MODE_ERTM;
1824			set_bit(CONF_STATE2_DEVICE, &chan->conf_state);
1825		} else {
1826			chan->mode = L2CAP_MODE_BASIC;
1827		}
1828
1829		l2cap_chan_set_defaults(chan);
1830	}
1831
1832	/* Default config options */
1833	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
1834
1835	chan->data = sk;
1836	chan->ops = &l2cap_chan_ops;
1837}
1838
1839static struct proto l2cap_proto = {
1840	.name		= "L2CAP",
1841	.owner		= THIS_MODULE,
1842	.obj_size	= sizeof(struct l2cap_pinfo)
1843};
1844
1845static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
1846				     int proto, gfp_t prio, int kern)
1847{
1848	struct sock *sk;
1849	struct l2cap_chan *chan;
1850
1851	sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto, kern);
1852	if (!sk)
1853		return NULL;
1854
1855	sock_init_data(sock, sk);
1856	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
1857
1858	sk->sk_destruct = l2cap_sock_destruct;
1859	sk->sk_sndtimeo = L2CAP_CONN_TIMEOUT;
1860
1861	sock_reset_flag(sk, SOCK_ZAPPED);
1862
1863	sk->sk_protocol = proto;
1864	sk->sk_state = BT_OPEN;
1865
1866	chan = l2cap_chan_create();
1867	if (!chan) {
1868		sk_free(sk);
1869		return NULL;
1870	}
1871
1872	l2cap_chan_hold(chan);
1873
1874	l2cap_pi(sk)->chan = chan;
1875
1876	return sk;
1877}
1878
1879static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
1880			     int kern)
1881{
1882	struct sock *sk;
1883
1884	BT_DBG("sock %p", sock);
1885
1886	sock->state = SS_UNCONNECTED;
1887
1888	if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM &&
1889	    sock->type != SOCK_DGRAM && sock->type != SOCK_RAW)
1890		return -ESOCKTNOSUPPORT;
1891
1892	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
1893		return -EPERM;
1894
1895	sock->ops = &l2cap_sock_ops;
1896
1897	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern);
1898	if (!sk)
1899		return -ENOMEM;
1900
1901	l2cap_sock_init(sk, NULL);
1902	bt_sock_link(&l2cap_sk_list, sk);
1903	return 0;
1904}
1905
1906static const struct proto_ops l2cap_sock_ops = {
1907	.family		= PF_BLUETOOTH,
1908	.owner		= THIS_MODULE,
1909	.release	= l2cap_sock_release,
1910	.bind		= l2cap_sock_bind,
1911	.connect	= l2cap_sock_connect,
1912	.listen		= l2cap_sock_listen,
1913	.accept		= l2cap_sock_accept,
1914	.getname	= l2cap_sock_getname,
1915	.sendmsg	= l2cap_sock_sendmsg,
1916	.recvmsg	= l2cap_sock_recvmsg,
1917	.poll		= bt_sock_poll,
1918	.ioctl		= bt_sock_ioctl,
1919	.gettstamp	= sock_gettstamp,
1920	.mmap		= sock_no_mmap,
1921	.socketpair	= sock_no_socketpair,
1922	.shutdown	= l2cap_sock_shutdown,
1923	.setsockopt	= l2cap_sock_setsockopt,
1924	.getsockopt	= l2cap_sock_getsockopt
1925};
1926
1927static const struct net_proto_family l2cap_sock_family_ops = {
1928	.family	= PF_BLUETOOTH,
1929	.owner	= THIS_MODULE,
1930	.create	= l2cap_sock_create,
1931};
1932
1933int __init l2cap_init_sockets(void)
1934{
1935	int err;
1936
1937	BUILD_BUG_ON(sizeof(struct sockaddr_l2) > sizeof(struct sockaddr));
1938
1939	err = proto_register(&l2cap_proto, 0);
1940	if (err < 0)
1941		return err;
1942
1943	err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops);
1944	if (err < 0) {
1945		BT_ERR("L2CAP socket registration failed");
1946		goto error;
1947	}
1948
1949	err = bt_procfs_init(&init_net, "l2cap", &l2cap_sk_list,
1950			     NULL);
1951	if (err < 0) {
1952		BT_ERR("Failed to create L2CAP proc file");
1953		bt_sock_unregister(BTPROTO_L2CAP);
1954		goto error;
1955	}
1956
1957	BT_INFO("L2CAP socket layer initialized");
1958
1959	return 0;
1960
1961error:
1962	proto_unregister(&l2cap_proto);
1963	return err;
1964}
1965
1966void l2cap_cleanup_sockets(void)
1967{
1968	bt_procfs_cleanup(&init_net, "l2cap");
1969	bt_sock_unregister(BTPROTO_L2CAP);
1970	proto_unregister(&l2cap_proto);
1971}