xref: /linux/fs/smb/server/transport_tcp.c (revision 9a58da80053f992b285b6b7bebc694b0f284c443)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
4  *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
5  */
6 
7 #include <linux/freezer.h>
8 
9 #include "smb_common.h"
10 #include "server.h"
11 #include "auth.h"
12 #include "connection.h"
13 #include "transport_tcp.h"
14 
15 #define IFACE_STATE_DOWN		BIT(0)
16 #define IFACE_STATE_CONFIGURED		BIT(1)
17 
18 static atomic_t active_num_conn;
19 
20 struct interface {
21 	struct task_struct	*ksmbd_kthread;
22 	struct socket		*ksmbd_socket;
23 	struct list_head	entry;
24 	char			*name;
25 	int			state;
26 };
27 
28 static LIST_HEAD(iface_list);
29 
30 static int bind_additional_ifaces;
31 
32 struct tcp_transport {
33 	struct ksmbd_transport		transport;
34 	struct socket			*sock;
35 	struct kvec			*iov;
36 	unsigned int			nr_iov;
37 };
38 
39 static const struct ksmbd_transport_ops ksmbd_tcp_transport_ops;
40 
41 static void tcp_stop_kthread(struct task_struct *kthread);
42 static void ksmbd_tcp_stop_listener(struct interface *iface);
43 static struct interface *alloc_iface(char *ifname);
44 static void ksmbd_tcp_disconnect(struct ksmbd_transport *t);
45 
46 #define KSMBD_TRANS(t)	(&(t)->transport)
47 #define TCP_TRANS(t)	((struct tcp_transport *)container_of(t, \
48 				struct tcp_transport, transport))
49 
ksmbd_tcp_nodelay(struct socket * sock)50 static inline void ksmbd_tcp_nodelay(struct socket *sock)
51 {
52 	tcp_sock_set_nodelay(sock->sk);
53 }
54 
ksmbd_tcp_reuseaddr(struct socket * sock)55 static inline void ksmbd_tcp_reuseaddr(struct socket *sock)
56 {
57 	sock_set_reuseaddr(sock->sk);
58 }
59 
alloc_transport(struct socket * client_sk)60 static struct tcp_transport *alloc_transport(struct socket *client_sk)
61 {
62 	struct tcp_transport *t;
63 	struct ksmbd_conn *conn;
64 
65 	t = kzalloc_obj(*t, KSMBD_DEFAULT_GFP);
66 	if (!t)
67 		return NULL;
68 	t->sock = client_sk;
69 
70 	conn = ksmbd_conn_alloc();
71 	if (!conn) {
72 		kfree(t);
73 		return NULL;
74 	}
75 
76 #if IS_ENABLED(CONFIG_IPV6)
77 	if (client_sk->sk->sk_family == AF_INET6) {
78 		memcpy(&conn->inet6_addr, &client_sk->sk->sk_v6_daddr, 16);
79 		conn->inet_hash = ipv6_addr_hash(&client_sk->sk->sk_v6_daddr);
80 	} else {
81 		conn->inet_addr = inet_sk(client_sk->sk)->inet_daddr;
82 		conn->inet_hash = ipv4_addr_hash(inet_sk(client_sk->sk)->inet_daddr);
83 	}
84 #else
85 	conn->inet_addr = inet_sk(client_sk->sk)->inet_daddr;
86 	conn->inet_hash = ipv4_addr_hash(inet_sk(client_sk->sk)->inet_daddr);
87 #endif
88 	down_write(&conn_list_lock);
89 	hash_add(conn_list, &conn->hlist, conn->inet_hash);
90 	up_write(&conn_list_lock);
91 
92 	conn->transport = KSMBD_TRANS(t);
93 	KSMBD_TRANS(t)->conn = conn;
94 	KSMBD_TRANS(t)->ops = &ksmbd_tcp_transport_ops;
95 	return t;
96 }
97 
ksmbd_tcp_free_transport(struct ksmbd_transport * kt)98 static void ksmbd_tcp_free_transport(struct ksmbd_transport *kt)
99 {
100 	struct tcp_transport *t = TCP_TRANS(kt);
101 
102 	sock_release(t->sock);
103 	kfree(t->iov);
104 	kfree(t);
105 }
106 
free_transport(struct tcp_transport * t)107 static void free_transport(struct tcp_transport *t)
108 {
109 	kernel_sock_shutdown(t->sock, SHUT_RDWR);
110 	ksmbd_conn_free(KSMBD_TRANS(t)->conn);
111 }
112 
113 /**
114  * kvec_array_init() - initialize a IO vector segment
115  * @new:	IO vector to be initialized
116  * @iov:	base IO vector
117  * @nr_segs:	number of segments in base iov
118  * @bytes:	total iovec length so far for read
119  *
120  * Return:	Number of IO segments
121  */
kvec_array_init(struct kvec * new,struct kvec * iov,unsigned int nr_segs,size_t bytes)122 static unsigned int kvec_array_init(struct kvec *new, struct kvec *iov,
123 				    unsigned int nr_segs, size_t bytes)
124 {
125 	size_t base = 0;
126 
127 	while (bytes || !iov->iov_len) {
128 		int copy = min(bytes, iov->iov_len);
129 
130 		bytes -= copy;
131 		base += copy;
132 		if (iov->iov_len == base) {
133 			iov++;
134 			nr_segs--;
135 			base = 0;
136 		}
137 	}
138 
139 	memcpy(new, iov, sizeof(*iov) * nr_segs);
140 	new->iov_base += base;
141 	new->iov_len -= base;
142 	return nr_segs;
143 }
144 
145 /**
146  * get_conn_iovec() - get connection iovec for reading from socket
147  * @t:		TCP transport instance
148  * @nr_segs:	number of segments in iov
149  *
150  * Return:	return existing or newly allocate iovec
151  */
get_conn_iovec(struct tcp_transport * t,unsigned int nr_segs)152 static struct kvec *get_conn_iovec(struct tcp_transport *t, unsigned int nr_segs)
153 {
154 	struct kvec *new_iov;
155 
156 	if (t->iov && nr_segs <= t->nr_iov)
157 		return t->iov;
158 
159 	/* not big enough -- allocate a new one and release the old */
160 	new_iov = kmalloc_objs(*new_iov, nr_segs, KSMBD_DEFAULT_GFP);
161 	if (new_iov) {
162 		kfree(t->iov);
163 		t->iov = new_iov;
164 		t->nr_iov = nr_segs;
165 	}
166 	return new_iov;
167 }
168 
169 /**
170  * ksmbd_tcp_new_connection() - create a new tcp session on mount
171  * @client_sk:	socket associated with new connection
172  *
173  * whenever a new connection is requested, create a conn thread
174  * (session thread) to handle new incoming smb requests from the connection
175  *
176  * Return:	0 on success, otherwise error
177  */
ksmbd_tcp_new_connection(struct socket * client_sk)178 static int ksmbd_tcp_new_connection(struct socket *client_sk)
179 {
180 	int rc = 0;
181 	struct tcp_transport *t;
182 	struct task_struct *handler;
183 
184 	t = alloc_transport(client_sk);
185 	if (!t) {
186 		sock_release(client_sk);
187 		if (server_conf.max_connections)
188 			atomic_dec(&active_num_conn);
189 		return -ENOMEM;
190 	}
191 
192 #if IS_ENABLED(CONFIG_IPV6)
193 	if (client_sk->sk->sk_family == AF_INET6)
194 		handler = kthread_run(ksmbd_conn_handler_loop,
195 				KSMBD_TRANS(t)->conn, "ksmbd:%pI6c",
196 				&KSMBD_TRANS(t)->conn->inet6_addr);
197 	else
198 		handler = kthread_run(ksmbd_conn_handler_loop,
199 				KSMBD_TRANS(t)->conn, "ksmbd:%pI4",
200 				&KSMBD_TRANS(t)->conn->inet_addr);
201 #else
202 	handler = kthread_run(ksmbd_conn_handler_loop,
203 			KSMBD_TRANS(t)->conn, "ksmbd:%pI4",
204 			&KSMBD_TRANS(t)->conn->inet_addr);
205 #endif
206 	if (IS_ERR(handler)) {
207 		pr_err("cannot start conn thread\n");
208 		rc = PTR_ERR(handler);
209 		ksmbd_tcp_disconnect(KSMBD_TRANS(t));
210 	}
211 	return rc;
212 }
213 
214 /**
215  * ksmbd_kthread_fn() - listen to new SMB connections and callback server
216  * @p:		arguments to forker thread
217  *
218  * Return:	0 on success, error number otherwise
219  */
ksmbd_kthread_fn(void * p)220 static int ksmbd_kthread_fn(void *p)
221 {
222 	struct socket *client_sk = NULL;
223 	struct interface *iface = (struct interface *)p;
224 	struct ksmbd_conn *conn;
225 	int ret, inet_hash;
226 	unsigned int max_ip_conns;
227 
228 	while (!kthread_should_stop()) {
229 		if (!iface->ksmbd_socket) {
230 			break;
231 		}
232 		ret = kernel_accept(iface->ksmbd_socket, &client_sk, 0);
233 		if (ret == -EINVAL)
234 			break;
235 		if (ret)
236 			continue;
237 
238 		if (!server_conf.max_ip_connections)
239 			goto skip_max_ip_conns_limit;
240 
241 		/*
242 		 * Limits repeated connections from clients with the same IP.
243 		 */
244 #if IS_ENABLED(CONFIG_IPV6)
245 		if (client_sk->sk->sk_family == AF_INET6)
246 			inet_hash = ipv6_addr_hash(&client_sk->sk->sk_v6_daddr);
247 		else
248 			inet_hash = ipv4_addr_hash(inet_sk(client_sk->sk)->inet_daddr);
249 #else
250 		inet_hash = ipv4_addr_hash(inet_sk(client_sk->sk)->inet_daddr);
251 #endif
252 
253 		max_ip_conns = 0;
254 		down_read(&conn_list_lock);
255 		hash_for_each_possible(conn_list, conn, hlist, inet_hash) {
256 #if IS_ENABLED(CONFIG_IPV6)
257 			if (client_sk->sk->sk_family == AF_INET6) {
258 				if (memcmp(&client_sk->sk->sk_v6_daddr,
259 					   &conn->inet6_addr, 16) == 0)
260 					max_ip_conns++;
261 			} else if (inet_sk(client_sk->sk)->inet_daddr ==
262 				 conn->inet_addr)
263 				max_ip_conns++;
264 #else
265 			if (inet_sk(client_sk->sk)->inet_daddr ==
266 			    conn->inet_addr)
267 				max_ip_conns++;
268 #endif
269 			if (server_conf.max_ip_connections <= max_ip_conns) {
270 				pr_info_ratelimited("Maximum IP connections exceeded (%u/%u)\n",
271 						    max_ip_conns, server_conf.max_ip_connections);
272 				ret = -EAGAIN;
273 				break;
274 			}
275 		}
276 		up_read(&conn_list_lock);
277 		if (ret == -EAGAIN) {
278 			/* Per-IP limit hit: release the just-accepted socket. */
279 			sock_release(client_sk);
280 			continue;
281 		}
282 
283 skip_max_ip_conns_limit:
284 		if (server_conf.max_connections &&
285 		    atomic_inc_return(&active_num_conn) > server_conf.max_connections) {
286 			pr_info_ratelimited("Limit the maximum number of connections(%u)\n",
287 					    atomic_read(&active_num_conn));
288 			atomic_dec(&active_num_conn);
289 			sock_release(client_sk);
290 			continue;
291 		}
292 
293 		ksmbd_debug(CONN, "connect success: accepted new connection\n");
294 		client_sk->sk->sk_rcvtimeo = KSMBD_TCP_RECV_TIMEOUT;
295 		client_sk->sk->sk_sndtimeo = KSMBD_TCP_SEND_TIMEOUT;
296 		/*
297 		 * Detect peers that disappear without sending a FIN or RST.
298 		 * Otherwise the connection handler can retry receive timeouts
299 		 * indefinitely and keep the connection in conn_list.
300 		 */
301 		sock_set_keepalive(client_sk->sk);
302 
303 		ksmbd_tcp_new_connection(client_sk);
304 	}
305 
306 	ksmbd_debug(CONN, "releasing socket\n");
307 	return 0;
308 }
309 
310 /**
311  * ksmbd_tcp_run_kthread() - start forker thread
312  * @iface: pointer to struct interface
313  *
314  * start forker thread(ksmbd/0) at module init time to listen
315  * on port 445 for new SMB connection requests. It creates per connection
316  * server threads(ksmbd/x)
317  *
318  * Return:	0 on success or error number
319  */
ksmbd_tcp_run_kthread(struct interface * iface)320 static int ksmbd_tcp_run_kthread(struct interface *iface)
321 {
322 	int rc;
323 	struct task_struct *kthread;
324 
325 	kthread = kthread_create(ksmbd_kthread_fn, (void *)iface, "ksmbd-%s",
326 				 iface->name);
327 	if (IS_ERR(kthread)) {
328 		rc = PTR_ERR(kthread);
329 		return rc;
330 	}
331 
332 	/*
333 	 * The listener can exit after its socket is shutdown, so keep the
334 	 * task_struct alive until the caller has stopped it.
335 	 */
336 	get_task_struct(kthread);
337 	iface->ksmbd_kthread = kthread;
338 	wake_up_process(kthread);
339 
340 	return 0;
341 }
342 
343 /**
344  * ksmbd_tcp_readv() - read data from socket in given iovec
345  * @t:			TCP transport instance
346  * @iov_orig:		base IO vector
347  * @nr_segs:		number of segments in base iov
348  * @to_read:		number of bytes to read from socket
349  * @max_retries:	maximum retry count
350  *
351  * Return:	on success return number of bytes read from socket,
352  *		otherwise return error number
353  */
ksmbd_tcp_readv(struct tcp_transport * t,struct kvec * iov_orig,unsigned int nr_segs,unsigned int to_read,int max_retries)354 static int ksmbd_tcp_readv(struct tcp_transport *t, struct kvec *iov_orig,
355 			   unsigned int nr_segs, unsigned int to_read,
356 			   int max_retries)
357 {
358 	int length = 0;
359 	int total_read;
360 	unsigned int segs;
361 	struct msghdr ksmbd_msg;
362 	struct kvec *iov;
363 	struct ksmbd_conn *conn = KSMBD_TRANS(t)->conn;
364 
365 	iov = get_conn_iovec(t, nr_segs);
366 	if (!iov)
367 		return -ENOMEM;
368 
369 	ksmbd_msg.msg_control = NULL;
370 	ksmbd_msg.msg_controllen = 0;
371 
372 	for (total_read = 0; to_read; total_read += length, to_read -= length) {
373 		try_to_freeze();
374 
375 		if (!ksmbd_conn_alive(conn)) {
376 			total_read = -ESHUTDOWN;
377 			break;
378 		}
379 		segs = kvec_array_init(iov, iov_orig, nr_segs, total_read);
380 
381 		length = kernel_recvmsg(t->sock, &ksmbd_msg,
382 					iov, segs, to_read, 0);
383 
384 		if (length == -EINTR) {
385 			total_read = -ESHUTDOWN;
386 			break;
387 		} else if (ksmbd_conn_need_reconnect(conn)) {
388 			total_read = -EAGAIN;
389 			break;
390 		} else if (length == -ERESTARTSYS || length == -EAGAIN) {
391 			/*
392 			 * If max_retries is negative, Allow unlimited
393 			 * retries to keep connection with inactive sessions.
394 			 */
395 			if (max_retries == 0) {
396 				total_read = length;
397 				break;
398 			} else if (max_retries > 0) {
399 				max_retries--;
400 			}
401 
402 			usleep_range(1000, 2000);
403 			length = 0;
404 			continue;
405 		} else if (length <= 0) {
406 			total_read = length;
407 			break;
408 		}
409 	}
410 	return total_read;
411 }
412 
413 /**
414  * ksmbd_tcp_read() - read data from socket in given buffer
415  * @t:		TCP transport instance
416  * @buf:	buffer to store read data from socket
417  * @to_read:	number of bytes to read from socket
418  * @max_retries: number of retries if reading from socket fails
419  *
420  * Return:	on success return number of bytes read from socket,
421  *		otherwise return error number
422  */
ksmbd_tcp_read(struct ksmbd_transport * t,char * buf,unsigned int to_read,int max_retries)423 static int ksmbd_tcp_read(struct ksmbd_transport *t, char *buf,
424 			  unsigned int to_read, int max_retries)
425 {
426 	struct kvec iov;
427 
428 	iov.iov_base = buf;
429 	iov.iov_len = to_read;
430 
431 	return ksmbd_tcp_readv(TCP_TRANS(t), &iov, 1, to_read, max_retries);
432 }
433 
ksmbd_tcp_writev(struct ksmbd_transport * t,const struct ksmbd_transport_write * tx)434 static int ksmbd_tcp_writev(struct ksmbd_transport *t,
435 			    const struct ksmbd_transport_write *tx)
436 {
437 	struct msghdr smb_msg = {
438 		.msg_flags = MSG_NOSIGNAL | tx->msg_flags,
439 	};
440 
441 	return kernel_sendmsg(TCP_TRANS(t)->sock, &smb_msg, tx->iov,
442 			      tx->iov_cnt, tx->size);
443 }
444 
ksmbd_tcp_disconnect(struct ksmbd_transport * t)445 static void ksmbd_tcp_disconnect(struct ksmbd_transport *t)
446 {
447 	free_transport(TCP_TRANS(t));
448 	if (server_conf.max_connections)
449 		atomic_dec(&active_num_conn);
450 }
451 
ksmbd_tcp_shutdown(struct ksmbd_transport * t)452 static void ksmbd_tcp_shutdown(struct ksmbd_transport *t)
453 {
454 	kernel_sock_shutdown(TCP_TRANS(t)->sock, SHUT_RDWR);
455 }
456 
tcp_destroy_socket(struct socket * ksmbd_socket)457 static void tcp_destroy_socket(struct socket *ksmbd_socket)
458 {
459 	int ret;
460 
461 	if (!ksmbd_socket)
462 		return;
463 
464 	ret = kernel_sock_shutdown(ksmbd_socket, SHUT_RDWR);
465 	if (ret)
466 		pr_err("Failed to shutdown socket: %d\n", ret);
467 	sock_release(ksmbd_socket);
468 }
469 
470 /**
471  * create_socket - create socket for ksmbd/0
472  * @iface:      interface to bind the created socket to
473  *
474  * Return:	0 on success, error number otherwise
475  */
create_socket(struct interface * iface)476 static int create_socket(struct interface *iface)
477 {
478 	int ret;
479 	struct sockaddr_in6 sin6;
480 	struct sockaddr_in sin;
481 	struct socket *ksmbd_socket;
482 	bool ipv4 = false;
483 
484 	ret = sock_create_kern(current->nsproxy->net_ns, PF_INET6, SOCK_STREAM,
485 			IPPROTO_TCP, &ksmbd_socket);
486 	if (ret) {
487 		if (ret != -EAFNOSUPPORT)
488 			pr_err("Can't create socket for ipv6, fallback to ipv4: %d\n", ret);
489 		ret = sock_create_kern(current->nsproxy->net_ns, PF_INET,
490 				SOCK_STREAM, IPPROTO_TCP, &ksmbd_socket);
491 		if (ret) {
492 			pr_err("Can't create socket for ipv4: %d\n", ret);
493 			goto out_clear;
494 		}
495 
496 		sin.sin_family = PF_INET;
497 		sin.sin_addr.s_addr = htonl(INADDR_ANY);
498 		sin.sin_port = htons(server_conf.tcp_port);
499 		ipv4 = true;
500 	} else {
501 		sin6.sin6_family = PF_INET6;
502 		sin6.sin6_addr = in6addr_any;
503 		sin6.sin6_port = htons(server_conf.tcp_port);
504 
505 		lock_sock(ksmbd_socket->sk);
506 		ksmbd_socket->sk->sk_ipv6only = false;
507 		release_sock(ksmbd_socket->sk);
508 	}
509 
510 	ksmbd_tcp_nodelay(ksmbd_socket);
511 	ksmbd_tcp_reuseaddr(ksmbd_socket);
512 
513 	ret = sock_setsockopt(ksmbd_socket,
514 			      SOL_SOCKET,
515 			      SO_BINDTODEVICE,
516 			      KERNEL_SOCKPTR(iface->name),
517 			      strlen(iface->name));
518 	if (ret != -ENODEV && ret < 0) {
519 		pr_err("Failed to set SO_BINDTODEVICE: %d\n", ret);
520 		goto out_error;
521 	}
522 
523 	if (ipv4)
524 		ret = kernel_bind(ksmbd_socket, (struct sockaddr_unsized *)&sin,
525 				  sizeof(sin));
526 	else
527 		ret = kernel_bind(ksmbd_socket, (struct sockaddr_unsized *)&sin6,
528 				  sizeof(sin6));
529 	if (ret) {
530 		pr_err("Failed to bind socket: %d\n", ret);
531 		goto out_error;
532 	}
533 
534 	/*
535 	 * Accepted sockets inherit the listener's net reference. Keep TCP
536 	 * timers alive after a kernel socket is released.
537 	 */
538 	sk_net_refcnt_upgrade(ksmbd_socket->sk);
539 
540 	ret = kernel_listen(ksmbd_socket, KSMBD_SOCKET_BACKLOG);
541 	if (ret) {
542 		pr_err("Port listen() error: %d\n", ret);
543 		goto out_error;
544 	}
545 
546 	iface->ksmbd_socket = ksmbd_socket;
547 	ret = ksmbd_tcp_run_kthread(iface);
548 	if (ret) {
549 		pr_err("Can't start ksmbd main kthread: %d\n", ret);
550 		goto out_error;
551 	}
552 	iface->state = IFACE_STATE_CONFIGURED;
553 
554 	return 0;
555 
556 out_error:
557 	tcp_destroy_socket(ksmbd_socket);
558 out_clear:
559 	iface->ksmbd_socket = NULL;
560 	return ret;
561 }
562 
ksmbd_find_netdev_name_iface_list(char * netdev_name)563 struct interface *ksmbd_find_netdev_name_iface_list(char *netdev_name)
564 {
565 	struct interface *iface;
566 
567 	list_for_each_entry(iface, &iface_list, entry)
568 		if (!strcmp(iface->name, netdev_name))
569 			return iface;
570 	return NULL;
571 }
572 
ksmbd_netdev_event(struct notifier_block * nb,unsigned long event,void * ptr)573 static int ksmbd_netdev_event(struct notifier_block *nb, unsigned long event,
574 			      void *ptr)
575 {
576 	struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
577 	struct interface *iface;
578 	int ret;
579 
580 	switch (event) {
581 	case NETDEV_UP:
582 		if (netif_is_bridge_port(netdev))
583 			return NOTIFY_OK;
584 
585 		iface = ksmbd_find_netdev_name_iface_list(netdev->name);
586 		if (iface && iface->state == IFACE_STATE_DOWN) {
587 			ksmbd_debug(CONN, "netdev-up event: netdev(%s) is going up\n",
588 					iface->name);
589 			ret = create_socket(iface);
590 			if (ret)
591 				return NOTIFY_OK;
592 		}
593 		if (!iface && bind_additional_ifaces) {
594 			iface = alloc_iface(kstrdup(netdev->name, KSMBD_DEFAULT_GFP));
595 			if (!iface)
596 				return NOTIFY_OK;
597 			ksmbd_debug(CONN, "netdev-up event: netdev(%s) is going up\n",
598 				    iface->name);
599 			ret = create_socket(iface);
600 			if (ret)
601 				break;
602 		}
603 		break;
604 	case NETDEV_DOWN:
605 		iface = ksmbd_find_netdev_name_iface_list(netdev->name);
606 		if (iface && iface->state == IFACE_STATE_CONFIGURED) {
607 			ksmbd_debug(CONN, "netdev-down event: netdev(%s) is going down\n",
608 					iface->name);
609 			ksmbd_tcp_stop_listener(iface);
610 			iface->state = IFACE_STATE_DOWN;
611 			break;
612 		}
613 		break;
614 	}
615 
616 	return NOTIFY_DONE;
617 }
618 
619 static struct notifier_block ksmbd_netdev_notifier = {
620 	.notifier_call = ksmbd_netdev_event,
621 };
622 
ksmbd_tcp_init(void)623 int ksmbd_tcp_init(void)
624 {
625 	register_netdevice_notifier(&ksmbd_netdev_notifier);
626 
627 	return 0;
628 }
629 
tcp_stop_kthread(struct task_struct * kthread)630 static void tcp_stop_kthread(struct task_struct *kthread)
631 {
632 	int ret;
633 
634 	if (!kthread)
635 		return;
636 
637 	ret = kthread_stop_put(kthread);
638 	if (ret)
639 		pr_err("failed to stop forker thread\n");
640 }
641 
ksmbd_tcp_stop_listener(struct interface * iface)642 static void ksmbd_tcp_stop_listener(struct interface *iface)
643 {
644 	if (iface->ksmbd_socket)
645 		kernel_sock_shutdown(iface->ksmbd_socket, SHUT_RDWR);
646 
647 	tcp_stop_kthread(iface->ksmbd_kthread);
648 	iface->ksmbd_kthread = NULL;
649 
650 	if (iface->ksmbd_socket) {
651 		sock_release(iface->ksmbd_socket);
652 		iface->ksmbd_socket = NULL;
653 	}
654 }
655 
ksmbd_tcp_destroy(void)656 void ksmbd_tcp_destroy(void)
657 {
658 	struct interface *iface, *tmp;
659 
660 	unregister_netdevice_notifier(&ksmbd_netdev_notifier);
661 
662 	list_for_each_entry_safe(iface, tmp, &iface_list, entry) {
663 		ksmbd_tcp_stop_listener(iface);
664 		list_del(&iface->entry);
665 		kfree(iface->name);
666 		kfree(iface);
667 	}
668 }
669 
alloc_iface(char * ifname)670 static struct interface *alloc_iface(char *ifname)
671 {
672 	struct interface *iface;
673 
674 	if (!ifname)
675 		return NULL;
676 
677 	iface = kzalloc_obj(struct interface, KSMBD_DEFAULT_GFP);
678 	if (!iface) {
679 		kfree(ifname);
680 		return NULL;
681 	}
682 
683 	iface->name = ifname;
684 	iface->state = IFACE_STATE_DOWN;
685 	list_add(&iface->entry, &iface_list);
686 	return iface;
687 }
688 
ksmbd_tcp_set_interfaces(char * ifc_list,int ifc_list_sz)689 int ksmbd_tcp_set_interfaces(char *ifc_list, int ifc_list_sz)
690 {
691 	int sz = 0;
692 
693 	if (!ifc_list_sz) {
694 		bind_additional_ifaces = 1;
695 		return 0;
696 	}
697 
698 	while (ifc_list_sz > 0) {
699 		if (!alloc_iface(kstrdup(ifc_list, KSMBD_DEFAULT_GFP)))
700 			return -ENOMEM;
701 
702 		sz = strlen(ifc_list);
703 		if (!sz)
704 			break;
705 
706 		ifc_list += sz + 1;
707 		ifc_list_sz -= (sz + 1);
708 	}
709 
710 	bind_additional_ifaces = 0;
711 
712 	return 0;
713 }
714 
715 static const struct ksmbd_transport_ops ksmbd_tcp_transport_ops = {
716 	.read		= ksmbd_tcp_read,
717 	.writev		= ksmbd_tcp_writev,
718 	.disconnect	= ksmbd_tcp_disconnect,
719 	.shutdown	= ksmbd_tcp_shutdown,
720 	.free_transport = ksmbd_tcp_free_transport,
721 };
722