xref: /openbmc/linux/net/mctp/af_mctp.c (revision f4df31a0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Management Component Transport Protocol (MCTP)
4  *
5  * Copyright (c) 2021 Code Construct
6  * Copyright (c) 2021 Google
7  */
8 
9 #include <linux/compat.h>
10 #include <linux/if_arp.h>
11 #include <linux/net.h>
12 #include <linux/mctp.h>
13 #include <linux/module.h>
14 #include <linux/socket.h>
15 
16 #include <net/mctp.h>
17 #include <net/mctpdevice.h>
18 #include <net/sock.h>
19 
20 #define CREATE_TRACE_POINTS
21 #include <trace/events/mctp.h>
22 
23 /* socket implementation */
24 
25 static void mctp_sk_expire_keys(struct timer_list *timer);
26 
mctp_release(struct socket * sock)27 static int mctp_release(struct socket *sock)
28 {
29 	struct sock *sk = sock->sk;
30 
31 	if (sk) {
32 		sock->sk = NULL;
33 		sk->sk_prot->close(sk, 0);
34 	}
35 
36 	return 0;
37 }
38 
39 /* Generic sockaddr checks, padding checks only so far */
mctp_sockaddr_is_ok(const struct sockaddr_mctp * addr)40 static bool mctp_sockaddr_is_ok(const struct sockaddr_mctp *addr)
41 {
42 	return !addr->__smctp_pad0 && !addr->__smctp_pad1;
43 }
44 
mctp_sockaddr_ext_is_ok(const struct sockaddr_mctp_ext * addr)45 static bool mctp_sockaddr_ext_is_ok(const struct sockaddr_mctp_ext *addr)
46 {
47 	return !addr->__smctp_pad0[0] &&
48 	       !addr->__smctp_pad0[1] &&
49 	       !addr->__smctp_pad0[2];
50 }
51 
mctp_bind(struct socket * sock,struct sockaddr * addr,int addrlen)52 static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
53 {
54 	struct sock *sk = sock->sk;
55 	struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
56 	struct sockaddr_mctp *smctp;
57 	int rc;
58 
59 	if (addrlen < sizeof(*smctp))
60 		return -EINVAL;
61 
62 	if (addr->sa_family != AF_MCTP)
63 		return -EAFNOSUPPORT;
64 
65 	if (!capable(CAP_NET_BIND_SERVICE))
66 		return -EACCES;
67 
68 	/* it's a valid sockaddr for MCTP, cast and do protocol checks */
69 	smctp = (struct sockaddr_mctp *)addr;
70 
71 	if (!mctp_sockaddr_is_ok(smctp))
72 		return -EINVAL;
73 
74 	lock_sock(sk);
75 
76 	/* TODO: allow rebind */
77 	if (sk_hashed(sk)) {
78 		rc = -EADDRINUSE;
79 		goto out_release;
80 	}
81 	msk->bind_net = smctp->smctp_network;
82 	msk->bind_addr = smctp->smctp_addr.s_addr;
83 	msk->bind_type = smctp->smctp_type & 0x7f; /* ignore the IC bit */
84 
85 	rc = sk->sk_prot->hash(sk);
86 
87 out_release:
88 	release_sock(sk);
89 
90 	return rc;
91 }
92 
mctp_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)93 static int mctp_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
94 {
95 	DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name);
96 	int rc, addrlen = msg->msg_namelen;
97 	struct sock *sk = sock->sk;
98 	struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
99 	struct mctp_skb_cb *cb;
100 	struct mctp_route *rt;
101 	struct sk_buff *skb = NULL;
102 	int hlen;
103 
104 	if (addr) {
105 		const u8 tagbits = MCTP_TAG_MASK | MCTP_TAG_OWNER |
106 			MCTP_TAG_PREALLOC;
107 
108 		if (addrlen < sizeof(struct sockaddr_mctp))
109 			return -EINVAL;
110 		if (addr->smctp_family != AF_MCTP)
111 			return -EINVAL;
112 		if (!mctp_sockaddr_is_ok(addr))
113 			return -EINVAL;
114 		if (addr->smctp_tag & ~tagbits)
115 			return -EINVAL;
116 		/* can't preallocate a non-owned tag */
117 		if (addr->smctp_tag & MCTP_TAG_PREALLOC &&
118 		    !(addr->smctp_tag & MCTP_TAG_OWNER))
119 			return -EINVAL;
120 
121 	} else {
122 		/* TODO: connect()ed sockets */
123 		return -EDESTADDRREQ;
124 	}
125 
126 	if (!capable(CAP_NET_RAW))
127 		return -EACCES;
128 
129 	if (addr->smctp_network == MCTP_NET_ANY)
130 		addr->smctp_network = mctp_default_net(sock_net(sk));
131 
132 	/* direct addressing */
133 	if (msk->addr_ext && addrlen >= sizeof(struct sockaddr_mctp_ext)) {
134 		DECLARE_SOCKADDR(struct sockaddr_mctp_ext *,
135 				 extaddr, msg->msg_name);
136 		struct net_device *dev;
137 
138 		rc = -EINVAL;
139 		rcu_read_lock();
140 		dev = dev_get_by_index_rcu(sock_net(sk), extaddr->smctp_ifindex);
141 		/* check for correct halen */
142 		if (dev && extaddr->smctp_halen == dev->addr_len) {
143 			hlen = LL_RESERVED_SPACE(dev) + sizeof(struct mctp_hdr);
144 			rc = 0;
145 		}
146 		rcu_read_unlock();
147 		if (rc)
148 			goto err_free;
149 		rt = NULL;
150 	} else {
151 		rt = mctp_route_lookup(sock_net(sk), addr->smctp_network,
152 				       addr->smctp_addr.s_addr);
153 		if (!rt) {
154 			rc = -EHOSTUNREACH;
155 			goto err_free;
156 		}
157 		hlen = LL_RESERVED_SPACE(rt->dev->dev) + sizeof(struct mctp_hdr);
158 	}
159 
160 	skb = sock_alloc_send_skb(sk, hlen + 1 + len,
161 				  msg->msg_flags & MSG_DONTWAIT, &rc);
162 	if (!skb)
163 		return rc;
164 
165 	skb_reserve(skb, hlen);
166 
167 	/* set type as fist byte in payload */
168 	*(u8 *)skb_put(skb, 1) = addr->smctp_type;
169 
170 	rc = memcpy_from_msg((void *)skb_put(skb, len), msg, len);
171 	if (rc < 0)
172 		goto err_free;
173 
174 	/* set up cb */
175 	cb = __mctp_cb(skb);
176 	cb->net = addr->smctp_network;
177 
178 	if (!rt) {
179 		/* fill extended address in cb */
180 		DECLARE_SOCKADDR(struct sockaddr_mctp_ext *,
181 				 extaddr, msg->msg_name);
182 
183 		if (!mctp_sockaddr_ext_is_ok(extaddr) ||
184 		    extaddr->smctp_halen > sizeof(cb->haddr)) {
185 			rc = -EINVAL;
186 			goto err_free;
187 		}
188 
189 		cb->ifindex = extaddr->smctp_ifindex;
190 		/* smctp_halen is checked above */
191 		cb->halen = extaddr->smctp_halen;
192 		memcpy(cb->haddr, extaddr->smctp_haddr, cb->halen);
193 	}
194 
195 	rc = mctp_local_output(sk, rt, skb, addr->smctp_addr.s_addr,
196 			       addr->smctp_tag);
197 
198 	return rc ? : len;
199 
200 err_free:
201 	kfree_skb(skb);
202 	return rc;
203 }
204 
mctp_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)205 static int mctp_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
206 			int flags)
207 {
208 	DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name);
209 	struct sock *sk = sock->sk;
210 	struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
211 	struct sk_buff *skb;
212 	size_t msglen;
213 	u8 type;
214 	int rc;
215 
216 	if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK))
217 		return -EOPNOTSUPP;
218 
219 	skb = skb_recv_datagram(sk, flags, &rc);
220 	if (!skb)
221 		return rc;
222 
223 	if (!skb->len) {
224 		rc = 0;
225 		goto out_free;
226 	}
227 
228 	/* extract message type, remove from data */
229 	type = *((u8 *)skb->data);
230 	msglen = skb->len - 1;
231 
232 	if (len < msglen)
233 		msg->msg_flags |= MSG_TRUNC;
234 	else
235 		len = msglen;
236 
237 	rc = skb_copy_datagram_msg(skb, 1, msg, len);
238 	if (rc < 0)
239 		goto out_free;
240 
241 	sock_recv_cmsgs(msg, sk, skb);
242 
243 	if (addr) {
244 		struct mctp_skb_cb *cb = mctp_cb(skb);
245 		/* TODO: expand mctp_skb_cb for header fields? */
246 		struct mctp_hdr *hdr = mctp_hdr(skb);
247 
248 		addr = msg->msg_name;
249 		addr->smctp_family = AF_MCTP;
250 		addr->__smctp_pad0 = 0;
251 		addr->smctp_network = cb->net;
252 		addr->smctp_addr.s_addr = hdr->src;
253 		addr->smctp_type = type;
254 		addr->smctp_tag = hdr->flags_seq_tag &
255 					(MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO);
256 		addr->__smctp_pad1 = 0;
257 		msg->msg_namelen = sizeof(*addr);
258 
259 		if (msk->addr_ext) {
260 			DECLARE_SOCKADDR(struct sockaddr_mctp_ext *, ae,
261 					 msg->msg_name);
262 			msg->msg_namelen = sizeof(*ae);
263 			ae->smctp_ifindex = cb->ifindex;
264 			ae->smctp_halen = cb->halen;
265 			memset(ae->__smctp_pad0, 0x0, sizeof(ae->__smctp_pad0));
266 			memset(ae->smctp_haddr, 0x0, sizeof(ae->smctp_haddr));
267 			memcpy(ae->smctp_haddr, cb->haddr, cb->halen);
268 		}
269 	}
270 
271 	rc = len;
272 
273 	if (flags & MSG_TRUNC)
274 		rc = msglen;
275 
276 out_free:
277 	skb_free_datagram(sk, skb);
278 	return rc;
279 }
280 
281 /* We're done with the key; invalidate, stop reassembly, and remove from lists.
282  */
__mctp_key_remove(struct mctp_sk_key * key,struct net * net,unsigned long flags,unsigned long reason)283 static void __mctp_key_remove(struct mctp_sk_key *key, struct net *net,
284 			      unsigned long flags, unsigned long reason)
285 __releases(&key->lock)
286 __must_hold(&net->mctp.keys_lock)
287 {
288 	struct sk_buff *skb;
289 
290 	trace_mctp_key_release(key, reason);
291 	skb = key->reasm_head;
292 	key->reasm_head = NULL;
293 	key->reasm_dead = true;
294 	key->valid = false;
295 	mctp_dev_release_key(key->dev, key);
296 	spin_unlock_irqrestore(&key->lock, flags);
297 
298 	if (!hlist_unhashed(&key->hlist)) {
299 		hlist_del_init(&key->hlist);
300 		hlist_del_init(&key->sklist);
301 		/* unref for the lists */
302 		mctp_key_unref(key);
303 	}
304 
305 	kfree_skb(skb);
306 }
307 
mctp_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)308 static int mctp_setsockopt(struct socket *sock, int level, int optname,
309 			   sockptr_t optval, unsigned int optlen)
310 {
311 	struct mctp_sock *msk = container_of(sock->sk, struct mctp_sock, sk);
312 	int val;
313 
314 	if (level != SOL_MCTP)
315 		return -EINVAL;
316 
317 	if (optname == MCTP_OPT_ADDR_EXT) {
318 		if (optlen != sizeof(int))
319 			return -EINVAL;
320 		if (copy_from_sockptr(&val, optval, sizeof(int)))
321 			return -EFAULT;
322 		msk->addr_ext = val;
323 		return 0;
324 	}
325 
326 	return -ENOPROTOOPT;
327 }
328 
mctp_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)329 static int mctp_getsockopt(struct socket *sock, int level, int optname,
330 			   char __user *optval, int __user *optlen)
331 {
332 	struct mctp_sock *msk = container_of(sock->sk, struct mctp_sock, sk);
333 	int len, val;
334 
335 	if (level != SOL_MCTP)
336 		return -EINVAL;
337 
338 	if (get_user(len, optlen))
339 		return -EFAULT;
340 
341 	if (optname == MCTP_OPT_ADDR_EXT) {
342 		if (len != sizeof(int))
343 			return -EINVAL;
344 		val = !!msk->addr_ext;
345 		if (copy_to_user(optval, &val, len))
346 			return -EFAULT;
347 		return 0;
348 	}
349 
350 	return -EINVAL;
351 }
352 
mctp_ioctl_alloctag(struct mctp_sock * msk,unsigned long arg)353 static int mctp_ioctl_alloctag(struct mctp_sock *msk, unsigned long arg)
354 {
355 	struct net *net = sock_net(&msk->sk);
356 	struct mctp_sk_key *key = NULL;
357 	struct mctp_ioc_tag_ctl ctl;
358 	unsigned long flags;
359 	u8 tag;
360 
361 	if (copy_from_user(&ctl, (void __user *)arg, sizeof(ctl)))
362 		return -EFAULT;
363 
364 	if (ctl.tag)
365 		return -EINVAL;
366 
367 	if (ctl.flags)
368 		return -EINVAL;
369 
370 	key = mctp_alloc_local_tag(msk, ctl.peer_addr, MCTP_ADDR_ANY,
371 				   true, &tag);
372 	if (IS_ERR(key))
373 		return PTR_ERR(key);
374 
375 	ctl.tag = tag | MCTP_TAG_OWNER | MCTP_TAG_PREALLOC;
376 	if (copy_to_user((void __user *)arg, &ctl, sizeof(ctl))) {
377 		unsigned long fl2;
378 		/* Unwind our key allocation: the keys list lock needs to be
379 		 * taken before the individual key locks, and we need a valid
380 		 * flags value (fl2) to pass to __mctp_key_remove, hence the
381 		 * second spin_lock_irqsave() rather than a plain spin_lock().
382 		 */
383 		spin_lock_irqsave(&net->mctp.keys_lock, flags);
384 		spin_lock_irqsave(&key->lock, fl2);
385 		__mctp_key_remove(key, net, fl2, MCTP_TRACE_KEY_DROPPED);
386 		mctp_key_unref(key);
387 		spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
388 		return -EFAULT;
389 	}
390 
391 	mctp_key_unref(key);
392 	return 0;
393 }
394 
mctp_ioctl_droptag(struct mctp_sock * msk,unsigned long arg)395 static int mctp_ioctl_droptag(struct mctp_sock *msk, unsigned long arg)
396 {
397 	struct net *net = sock_net(&msk->sk);
398 	struct mctp_ioc_tag_ctl ctl;
399 	unsigned long flags, fl2;
400 	struct mctp_sk_key *key;
401 	struct hlist_node *tmp;
402 	int rc;
403 	u8 tag;
404 
405 	if (copy_from_user(&ctl, (void __user *)arg, sizeof(ctl)))
406 		return -EFAULT;
407 
408 	if (ctl.flags)
409 		return -EINVAL;
410 
411 	/* Must be a local tag, TO set, preallocated */
412 	if ((ctl.tag & ~MCTP_TAG_MASK) != (MCTP_TAG_OWNER | MCTP_TAG_PREALLOC))
413 		return -EINVAL;
414 
415 	tag = ctl.tag & MCTP_TAG_MASK;
416 	rc = -EINVAL;
417 
418 	spin_lock_irqsave(&net->mctp.keys_lock, flags);
419 	hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
420 		/* we do an irqsave here, even though we know the irq state,
421 		 * so we have the flags to pass to __mctp_key_remove
422 		 */
423 		spin_lock_irqsave(&key->lock, fl2);
424 		if (key->manual_alloc &&
425 		    ctl.peer_addr == key->peer_addr &&
426 		    tag == key->tag) {
427 			__mctp_key_remove(key, net, fl2,
428 					  MCTP_TRACE_KEY_DROPPED);
429 			rc = 0;
430 		} else {
431 			spin_unlock_irqrestore(&key->lock, fl2);
432 		}
433 	}
434 	spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
435 
436 	return rc;
437 }
438 
mctp_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)439 static int mctp_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
440 {
441 	struct mctp_sock *msk = container_of(sock->sk, struct mctp_sock, sk);
442 
443 	switch (cmd) {
444 	case SIOCMCTPALLOCTAG:
445 		return mctp_ioctl_alloctag(msk, arg);
446 	case SIOCMCTPDROPTAG:
447 		return mctp_ioctl_droptag(msk, arg);
448 	}
449 
450 	return -EINVAL;
451 }
452 
453 #ifdef CONFIG_COMPAT
mctp_compat_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)454 static int mctp_compat_ioctl(struct socket *sock, unsigned int cmd,
455 			     unsigned long arg)
456 {
457 	void __user *argp = compat_ptr(arg);
458 
459 	switch (cmd) {
460 	/* These have compatible ptr layouts */
461 	case SIOCMCTPALLOCTAG:
462 	case SIOCMCTPDROPTAG:
463 		return mctp_ioctl(sock, cmd, (unsigned long)argp);
464 	}
465 
466 	return -ENOIOCTLCMD;
467 }
468 #endif
469 
470 static const struct proto_ops mctp_dgram_ops = {
471 	.family		= PF_MCTP,
472 	.release	= mctp_release,
473 	.bind		= mctp_bind,
474 	.connect	= sock_no_connect,
475 	.socketpair	= sock_no_socketpair,
476 	.accept		= sock_no_accept,
477 	.getname	= sock_no_getname,
478 	.poll		= datagram_poll,
479 	.ioctl		= mctp_ioctl,
480 	.gettstamp	= sock_gettstamp,
481 	.listen		= sock_no_listen,
482 	.shutdown	= sock_no_shutdown,
483 	.setsockopt	= mctp_setsockopt,
484 	.getsockopt	= mctp_getsockopt,
485 	.sendmsg	= mctp_sendmsg,
486 	.recvmsg	= mctp_recvmsg,
487 	.mmap		= sock_no_mmap,
488 #ifdef CONFIG_COMPAT
489 	.compat_ioctl	= mctp_compat_ioctl,
490 #endif
491 };
492 
mctp_sk_expire_keys(struct timer_list * timer)493 static void mctp_sk_expire_keys(struct timer_list *timer)
494 {
495 	struct mctp_sock *msk = container_of(timer, struct mctp_sock,
496 					     key_expiry);
497 	struct net *net = sock_net(&msk->sk);
498 	unsigned long next_expiry, flags, fl2;
499 	struct mctp_sk_key *key;
500 	struct hlist_node *tmp;
501 	bool next_expiry_valid = false;
502 
503 	spin_lock_irqsave(&net->mctp.keys_lock, flags);
504 
505 	hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
506 		/* don't expire. manual_alloc is immutable, no locking
507 		 * required.
508 		 */
509 		if (key->manual_alloc)
510 			continue;
511 
512 		spin_lock_irqsave(&key->lock, fl2);
513 		if (!time_after_eq(key->expiry, jiffies)) {
514 			__mctp_key_remove(key, net, fl2,
515 					  MCTP_TRACE_KEY_TIMEOUT);
516 			continue;
517 		}
518 
519 		if (next_expiry_valid) {
520 			if (time_before(key->expiry, next_expiry))
521 				next_expiry = key->expiry;
522 		} else {
523 			next_expiry = key->expiry;
524 			next_expiry_valid = true;
525 		}
526 		spin_unlock_irqrestore(&key->lock, fl2);
527 	}
528 
529 	spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
530 
531 	if (next_expiry_valid)
532 		mod_timer(timer, next_expiry);
533 }
534 
mctp_sk_init(struct sock * sk)535 static int mctp_sk_init(struct sock *sk)
536 {
537 	struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
538 
539 	INIT_HLIST_HEAD(&msk->keys);
540 	timer_setup(&msk->key_expiry, mctp_sk_expire_keys, 0);
541 	return 0;
542 }
543 
mctp_sk_close(struct sock * sk,long timeout)544 static void mctp_sk_close(struct sock *sk, long timeout)
545 {
546 	sk_common_release(sk);
547 }
548 
mctp_sk_hash(struct sock * sk)549 static int mctp_sk_hash(struct sock *sk)
550 {
551 	struct net *net = sock_net(sk);
552 
553 	mutex_lock(&net->mctp.bind_lock);
554 	sk_add_node_rcu(sk, &net->mctp.binds);
555 	mutex_unlock(&net->mctp.bind_lock);
556 
557 	return 0;
558 }
559 
mctp_sk_unhash(struct sock * sk)560 static void mctp_sk_unhash(struct sock *sk)
561 {
562 	struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
563 	struct net *net = sock_net(sk);
564 	unsigned long flags, fl2;
565 	struct mctp_sk_key *key;
566 	struct hlist_node *tmp;
567 
568 	/* remove from any type-based binds */
569 	mutex_lock(&net->mctp.bind_lock);
570 	sk_del_node_init_rcu(sk);
571 	mutex_unlock(&net->mctp.bind_lock);
572 
573 	/* remove tag allocations */
574 	spin_lock_irqsave(&net->mctp.keys_lock, flags);
575 	hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
576 		spin_lock_irqsave(&key->lock, fl2);
577 		__mctp_key_remove(key, net, fl2, MCTP_TRACE_KEY_CLOSED);
578 	}
579 	sock_set_flag(sk, SOCK_DEAD);
580 	spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
581 
582 	/* Since there are no more tag allocations (we have removed all of the
583 	 * keys), stop any pending expiry events. the timer cannot be re-queued
584 	 * as the sk is no longer observable
585 	 */
586 	del_timer_sync(&msk->key_expiry);
587 }
588 
mctp_sk_destruct(struct sock * sk)589 static void mctp_sk_destruct(struct sock *sk)
590 {
591 	skb_queue_purge(&sk->sk_receive_queue);
592 }
593 
594 static struct proto mctp_proto = {
595 	.name		= "MCTP",
596 	.owner		= THIS_MODULE,
597 	.obj_size	= sizeof(struct mctp_sock),
598 	.init		= mctp_sk_init,
599 	.close		= mctp_sk_close,
600 	.hash		= mctp_sk_hash,
601 	.unhash		= mctp_sk_unhash,
602 };
603 
mctp_pf_create(struct net * net,struct socket * sock,int protocol,int kern)604 static int mctp_pf_create(struct net *net, struct socket *sock,
605 			  int protocol, int kern)
606 {
607 	const struct proto_ops *ops;
608 	struct proto *proto;
609 	struct sock *sk;
610 	int rc;
611 
612 	if (protocol)
613 		return -EPROTONOSUPPORT;
614 
615 	/* only datagram sockets are supported */
616 	if (sock->type != SOCK_DGRAM)
617 		return -ESOCKTNOSUPPORT;
618 
619 	proto = &mctp_proto;
620 	ops = &mctp_dgram_ops;
621 
622 	sock->state = SS_UNCONNECTED;
623 	sock->ops = ops;
624 
625 	sk = sk_alloc(net, PF_MCTP, GFP_KERNEL, proto, kern);
626 	if (!sk)
627 		return -ENOMEM;
628 
629 	sock_init_data(sock, sk);
630 	sk->sk_destruct = mctp_sk_destruct;
631 
632 	rc = 0;
633 	if (sk->sk_prot->init)
634 		rc = sk->sk_prot->init(sk);
635 
636 	if (rc)
637 		goto err_sk_put;
638 
639 	return 0;
640 
641 err_sk_put:
642 	sock_orphan(sk);
643 	sock_put(sk);
644 	return rc;
645 }
646 
647 static struct net_proto_family mctp_pf = {
648 	.family = PF_MCTP,
649 	.create = mctp_pf_create,
650 	.owner = THIS_MODULE,
651 };
652 
mctp_init(void)653 static __init int mctp_init(void)
654 {
655 	int rc;
656 
657 	/* ensure our uapi tag definitions match the header format */
658 	BUILD_BUG_ON(MCTP_TAG_OWNER != MCTP_HDR_FLAG_TO);
659 	BUILD_BUG_ON(MCTP_TAG_MASK != MCTP_HDR_TAG_MASK);
660 
661 	pr_info("mctp: management component transport protocol core\n");
662 
663 	rc = sock_register(&mctp_pf);
664 	if (rc)
665 		return rc;
666 
667 	rc = proto_register(&mctp_proto, 0);
668 	if (rc)
669 		goto err_unreg_sock;
670 
671 	rc = mctp_routes_init();
672 	if (rc)
673 		goto err_unreg_proto;
674 
675 	rc = mctp_neigh_init();
676 	if (rc)
677 		goto err_unreg_routes;
678 
679 	rc = mctp_device_init();
680 	if (rc)
681 		goto err_unreg_neigh;
682 
683 	return 0;
684 
685 err_unreg_neigh:
686 	mctp_neigh_exit();
687 err_unreg_routes:
688 	mctp_routes_exit();
689 err_unreg_proto:
690 	proto_unregister(&mctp_proto);
691 err_unreg_sock:
692 	sock_unregister(PF_MCTP);
693 
694 	return rc;
695 }
696 
mctp_exit(void)697 static __exit void mctp_exit(void)
698 {
699 	mctp_device_exit();
700 	mctp_neigh_exit();
701 	mctp_routes_exit();
702 	proto_unregister(&mctp_proto);
703 	sock_unregister(PF_MCTP);
704 }
705 
706 subsys_initcall(mctp_init);
707 module_exit(mctp_exit);
708 
709 MODULE_DESCRIPTION("MCTP core");
710 MODULE_AUTHOR("Jeremy Kerr <jk@codeconstruct.com.au>");
711 
712 MODULE_ALIAS_NETPROTO(PF_MCTP);
713