1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * VMware vSockets Driver
4 *
5 * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
6 */
7
8 /* Implementation notes:
9 *
10 * - There are two kinds of sockets: those created by user action (such as
11 * calling socket(2)) and those created by incoming connection request packets.
12 *
13 * - There are two "global" tables, one for bound sockets (sockets that have
14 * specified an address that they are responsible for) and one for connected
15 * sockets (sockets that have established a connection with another socket).
16 * These tables are "global" in that all sockets on the system are placed
17 * within them. - Note, though, that the bound table contains an extra entry
18 * for a list of unbound sockets and SOCK_DGRAM sockets will always remain in
19 * that list. The bound table is used solely for lookup of sockets when packets
20 * are received and that's not necessary for SOCK_DGRAM sockets since we create
21 * a datagram handle for each and need not perform a lookup. Keeping SOCK_DGRAM
22 * sockets out of the bound hash buckets will reduce the chance of collisions
23 * when looking for SOCK_STREAM sockets and prevents us from having to check the
24 * socket type in the hash table lookups.
25 *
26 * - Sockets created by user action will either be "client" sockets that
27 * initiate a connection or "server" sockets that listen for connections; we do
28 * not support simultaneous connects (two "client" sockets connecting).
29 *
30 * - "Server" sockets are referred to as listener sockets throughout this
31 * implementation because they are in the TCP_LISTEN state. When a
32 * connection request is received (the second kind of socket mentioned above),
33 * we create a new socket and refer to it as a pending socket. These pending
34 * sockets are placed on the pending connection list of the listener socket.
35 * When future packets are received for the address the listener socket is
36 * bound to, we check if the source of the packet is from one that has an
37 * existing pending connection. If it does, we process the packet for the
38 * pending socket. When that socket reaches the connected state, it is removed
39 * from the listener socket's pending list and enqueued in the listener
40 * socket's accept queue. Callers of accept(2) will accept connected sockets
41 * from the listener socket's accept queue. If the socket cannot be accepted
42 * for some reason then it is marked rejected. Once the connection is
43 * accepted, it is owned by the user process and the responsibility for cleanup
44 * falls with that user process.
45 *
46 * - It is possible that these pending sockets will never reach the connected
47 * state; in fact, we may never receive another packet after the connection
48 * request. Because of this, we must schedule a cleanup function to run in the
49 * future, after some amount of time passes where a connection should have been
50 * established. This function ensures that the socket is off all lists so it
51 * cannot be retrieved, then drops all references to the socket so it is cleaned
52 * up (sock_put() -> sk_free() -> our sk_destruct implementation). Note this
53 * function will also cleanup rejected sockets, those that reach the connected
54 * state but leave it before they have been accepted.
55 *
56 * - Lock ordering for pending or accept queue sockets is:
57 *
58 * lock_sock(listener);
59 * lock_sock_nested(pending, SINGLE_DEPTH_NESTING);
60 *
61 * Using explicit nested locking keeps lockdep happy since normally only one
62 * lock of a given class may be taken at a time.
63 *
64 * - Sockets created by user action will be cleaned up when the user process
65 * calls close(2), causing our release implementation to be called. Our release
66 * implementation will perform some cleanup then drop the last reference so our
67 * sk_destruct implementation is invoked. Our sk_destruct implementation will
68 * perform additional cleanup that's common for both types of sockets.
69 *
70 * - A socket's reference count is what ensures that the structure won't be
71 * freed. Each entry in a list (such as the "global" bound and connected tables
72 * and the listener socket's pending list and connected queue) ensures a
73 * reference. When we defer work until process context and pass a socket as our
74 * argument, we must ensure the reference count is increased to ensure the
75 * socket isn't freed before the function is run; the deferred function will
76 * then drop the reference.
77 *
78 * - sk->sk_state uses the TCP state constants because they are widely used by
79 * other address families and exposed to userspace tools like ss(8):
80 *
81 * TCP_CLOSE - unconnected
82 * TCP_SYN_SENT - connecting
83 * TCP_ESTABLISHED - connected
84 * TCP_CLOSING - disconnecting
85 * TCP_LISTEN - listening
86 */
87
88 #include <linux/types.h>
89 #include <linux/bitops.h>
90 #include <linux/cred.h>
91 #include <linux/init.h>
92 #include <linux/io.h>
93 #include <linux/kernel.h>
94 #include <linux/sched/signal.h>
95 #include <linux/kmod.h>
96 #include <linux/list.h>
97 #include <linux/miscdevice.h>
98 #include <linux/module.h>
99 #include <linux/mutex.h>
100 #include <linux/net.h>
101 #include <linux/poll.h>
102 #include <linux/random.h>
103 #include <linux/skbuff.h>
104 #include <linux/smp.h>
105 #include <linux/socket.h>
106 #include <linux/stddef.h>
107 #include <linux/unistd.h>
108 #include <linux/wait.h>
109 #include <linux/workqueue.h>
110 #include <net/sock.h>
111 #include <net/af_vsock.h>
112
113 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
114 static void vsock_sk_destruct(struct sock *sk);
115 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
116
117 /* Protocol family. */
118 static struct proto vsock_proto = {
119 .name = "AF_VSOCK",
120 .owner = THIS_MODULE,
121 .obj_size = sizeof(struct vsock_sock),
122 };
123
124 /* The default peer timeout indicates how long we will wait for a peer response
125 * to a control message.
126 */
127 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
128
129 #define VSOCK_DEFAULT_BUFFER_SIZE (1024 * 256)
130 #define VSOCK_DEFAULT_BUFFER_MAX_SIZE (1024 * 256)
131 #define VSOCK_DEFAULT_BUFFER_MIN_SIZE 128
132
133 /* Transport used for host->guest communication */
134 static const struct vsock_transport *transport_h2g;
135 /* Transport used for guest->host communication */
136 static const struct vsock_transport *transport_g2h;
137 /* Transport used for DGRAM communication */
138 static const struct vsock_transport *transport_dgram;
139 /* Transport used for local communication */
140 static const struct vsock_transport *transport_local;
141 static DEFINE_MUTEX(vsock_register_mutex);
142
143 /**** UTILS ****/
144
145 /* Each bound VSocket is stored in the bind hash table and each connected
146 * VSocket is stored in the connected hash table.
147 *
148 * Unbound sockets are all put on the same list attached to the end of the hash
149 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in
150 * the bucket that their local address hashes to (vsock_bound_sockets(addr)
151 * represents the list that addr hashes to).
152 *
153 * Specifically, we initialize the vsock_bind_table array to a size of
154 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through
155 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and
156 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function
157 * mods with VSOCK_HASH_SIZE to ensure this.
158 */
159 #define MAX_PORT_RETRIES 24
160
161 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE)
162 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)])
163 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE])
164
165 /* XXX This can probably be implemented in a better way. */
166 #define VSOCK_CONN_HASH(src, dst) \
167 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE)
168 #define vsock_connected_sockets(src, dst) \
169 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)])
170 #define vsock_connected_sockets_vsk(vsk) \
171 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr)
172
173 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
174 EXPORT_SYMBOL_GPL(vsock_bind_table);
175 struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
176 EXPORT_SYMBOL_GPL(vsock_connected_table);
177 DEFINE_SPINLOCK(vsock_table_lock);
178 EXPORT_SYMBOL_GPL(vsock_table_lock);
179
180 /* Autobind this socket to the local address if necessary. */
vsock_auto_bind(struct vsock_sock * vsk)181 static int vsock_auto_bind(struct vsock_sock *vsk)
182 {
183 struct sock *sk = sk_vsock(vsk);
184 struct sockaddr_vm local_addr;
185
186 if (vsock_addr_bound(&vsk->local_addr))
187 return 0;
188 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
189 return __vsock_bind(sk, &local_addr);
190 }
191
vsock_init_tables(void)192 static void vsock_init_tables(void)
193 {
194 int i;
195
196 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++)
197 INIT_LIST_HEAD(&vsock_bind_table[i]);
198
199 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++)
200 INIT_LIST_HEAD(&vsock_connected_table[i]);
201 }
202
__vsock_insert_bound(struct list_head * list,struct vsock_sock * vsk)203 static void __vsock_insert_bound(struct list_head *list,
204 struct vsock_sock *vsk)
205 {
206 sock_hold(&vsk->sk);
207 list_add(&vsk->bound_table, list);
208 }
209
__vsock_insert_connected(struct list_head * list,struct vsock_sock * vsk)210 static void __vsock_insert_connected(struct list_head *list,
211 struct vsock_sock *vsk)
212 {
213 sock_hold(&vsk->sk);
214 list_add(&vsk->connected_table, list);
215 }
216
__vsock_remove_bound(struct vsock_sock * vsk)217 static void __vsock_remove_bound(struct vsock_sock *vsk)
218 {
219 list_del_init(&vsk->bound_table);
220 sock_put(&vsk->sk);
221 }
222
__vsock_remove_connected(struct vsock_sock * vsk)223 static void __vsock_remove_connected(struct vsock_sock *vsk)
224 {
225 list_del_init(&vsk->connected_table);
226 sock_put(&vsk->sk);
227 }
228
__vsock_find_bound_socket(struct sockaddr_vm * addr)229 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
230 {
231 struct vsock_sock *vsk;
232
233 list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) {
234 if (vsock_addr_equals_addr(addr, &vsk->local_addr))
235 return sk_vsock(vsk);
236
237 if (addr->svm_port == vsk->local_addr.svm_port &&
238 (vsk->local_addr.svm_cid == VMADDR_CID_ANY ||
239 addr->svm_cid == VMADDR_CID_ANY))
240 return sk_vsock(vsk);
241 }
242
243 return NULL;
244 }
245
__vsock_find_connected_socket(struct sockaddr_vm * src,struct sockaddr_vm * dst)246 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
247 struct sockaddr_vm *dst)
248 {
249 struct vsock_sock *vsk;
250
251 list_for_each_entry(vsk, vsock_connected_sockets(src, dst),
252 connected_table) {
253 if (vsock_addr_equals_addr(src, &vsk->remote_addr) &&
254 dst->svm_port == vsk->local_addr.svm_port) {
255 return sk_vsock(vsk);
256 }
257 }
258
259 return NULL;
260 }
261
vsock_insert_unbound(struct vsock_sock * vsk)262 static void vsock_insert_unbound(struct vsock_sock *vsk)
263 {
264 spin_lock_bh(&vsock_table_lock);
265 __vsock_insert_bound(vsock_unbound_sockets, vsk);
266 spin_unlock_bh(&vsock_table_lock);
267 }
268
vsock_insert_connected(struct vsock_sock * vsk)269 void vsock_insert_connected(struct vsock_sock *vsk)
270 {
271 struct list_head *list = vsock_connected_sockets(
272 &vsk->remote_addr, &vsk->local_addr);
273
274 spin_lock_bh(&vsock_table_lock);
275 __vsock_insert_connected(list, vsk);
276 spin_unlock_bh(&vsock_table_lock);
277 }
278 EXPORT_SYMBOL_GPL(vsock_insert_connected);
279
vsock_remove_bound(struct vsock_sock * vsk)280 void vsock_remove_bound(struct vsock_sock *vsk)
281 {
282 spin_lock_bh(&vsock_table_lock);
283 if (__vsock_in_bound_table(vsk))
284 __vsock_remove_bound(vsk);
285 spin_unlock_bh(&vsock_table_lock);
286 }
287 EXPORT_SYMBOL_GPL(vsock_remove_bound);
288
vsock_remove_connected(struct vsock_sock * vsk)289 void vsock_remove_connected(struct vsock_sock *vsk)
290 {
291 spin_lock_bh(&vsock_table_lock);
292 if (__vsock_in_connected_table(vsk))
293 __vsock_remove_connected(vsk);
294 spin_unlock_bh(&vsock_table_lock);
295 }
296 EXPORT_SYMBOL_GPL(vsock_remove_connected);
297
vsock_find_bound_socket(struct sockaddr_vm * addr)298 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr)
299 {
300 struct sock *sk;
301
302 spin_lock_bh(&vsock_table_lock);
303 sk = __vsock_find_bound_socket(addr);
304 if (sk)
305 sock_hold(sk);
306
307 spin_unlock_bh(&vsock_table_lock);
308
309 return sk;
310 }
311 EXPORT_SYMBOL_GPL(vsock_find_bound_socket);
312
vsock_find_connected_socket(struct sockaddr_vm * src,struct sockaddr_vm * dst)313 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
314 struct sockaddr_vm *dst)
315 {
316 struct sock *sk;
317
318 spin_lock_bh(&vsock_table_lock);
319 sk = __vsock_find_connected_socket(src, dst);
320 if (sk)
321 sock_hold(sk);
322
323 spin_unlock_bh(&vsock_table_lock);
324
325 return sk;
326 }
327 EXPORT_SYMBOL_GPL(vsock_find_connected_socket);
328
vsock_remove_sock(struct vsock_sock * vsk)329 void vsock_remove_sock(struct vsock_sock *vsk)
330 {
331 vsock_remove_bound(vsk);
332 vsock_remove_connected(vsk);
333 }
334 EXPORT_SYMBOL_GPL(vsock_remove_sock);
335
vsock_for_each_connected_socket(void (* fn)(struct sock * sk))336 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk))
337 {
338 int i;
339
340 spin_lock_bh(&vsock_table_lock);
341
342 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) {
343 struct vsock_sock *vsk;
344 list_for_each_entry(vsk, &vsock_connected_table[i],
345 connected_table)
346 fn(sk_vsock(vsk));
347 }
348
349 spin_unlock_bh(&vsock_table_lock);
350 }
351 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket);
352
vsock_add_pending(struct sock * listener,struct sock * pending)353 void vsock_add_pending(struct sock *listener, struct sock *pending)
354 {
355 struct vsock_sock *vlistener;
356 struct vsock_sock *vpending;
357
358 vlistener = vsock_sk(listener);
359 vpending = vsock_sk(pending);
360
361 sock_hold(pending);
362 sock_hold(listener);
363 list_add_tail(&vpending->pending_links, &vlistener->pending_links);
364 }
365 EXPORT_SYMBOL_GPL(vsock_add_pending);
366
vsock_remove_pending(struct sock * listener,struct sock * pending)367 void vsock_remove_pending(struct sock *listener, struct sock *pending)
368 {
369 struct vsock_sock *vpending = vsock_sk(pending);
370
371 list_del_init(&vpending->pending_links);
372 sock_put(listener);
373 sock_put(pending);
374 }
375 EXPORT_SYMBOL_GPL(vsock_remove_pending);
376
vsock_enqueue_accept(struct sock * listener,struct sock * connected)377 void vsock_enqueue_accept(struct sock *listener, struct sock *connected)
378 {
379 struct vsock_sock *vlistener;
380 struct vsock_sock *vconnected;
381
382 vlistener = vsock_sk(listener);
383 vconnected = vsock_sk(connected);
384
385 sock_hold(connected);
386 sock_hold(listener);
387 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue);
388 }
389 EXPORT_SYMBOL_GPL(vsock_enqueue_accept);
390
vsock_use_local_transport(unsigned int remote_cid)391 static bool vsock_use_local_transport(unsigned int remote_cid)
392 {
393 if (!transport_local)
394 return false;
395
396 if (remote_cid == VMADDR_CID_LOCAL)
397 return true;
398
399 if (transport_g2h) {
400 return remote_cid == transport_g2h->get_local_cid();
401 } else {
402 return remote_cid == VMADDR_CID_HOST;
403 }
404 }
405
vsock_deassign_transport(struct vsock_sock * vsk)406 static void vsock_deassign_transport(struct vsock_sock *vsk)
407 {
408 if (!vsk->transport)
409 return;
410
411 vsk->transport->destruct(vsk);
412 module_put(vsk->transport->module);
413 vsk->transport = NULL;
414 }
415
416 /* Assign a transport to a socket and call the .init transport callback.
417 *
418 * Note: for stream socket this must be called when vsk->remote_addr is set
419 * (e.g. during the connect() or when a connection request on a listener
420 * socket is received).
421 * The vsk->remote_addr is used to decide which transport to use:
422 * - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if
423 * g2h is not loaded, will use local transport;
424 * - remote CID <= VMADDR_CID_HOST or h2g is not loaded or remote flags field
425 * includes VMADDR_FLAG_TO_HOST flag value, will use guest->host transport;
426 * - remote CID > VMADDR_CID_HOST will use host->guest transport;
427 */
vsock_assign_transport(struct vsock_sock * vsk,struct vsock_sock * psk)428 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
429 {
430 const struct vsock_transport *new_transport;
431 struct sock *sk = sk_vsock(vsk);
432 unsigned int remote_cid = vsk->remote_addr.svm_cid;
433 __u8 remote_flags;
434 int ret;
435
436 /* If the packet is coming with the source and destination CIDs higher
437 * than VMADDR_CID_HOST, then a vsock channel where all the packets are
438 * forwarded to the host should be established. Then the host will
439 * need to forward the packets to the guest.
440 *
441 * The flag is set on the (listen) receive path (psk is not NULL). On
442 * the connect path the flag can be set by the user space application.
443 */
444 if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST &&
445 vsk->remote_addr.svm_cid > VMADDR_CID_HOST)
446 vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST;
447
448 remote_flags = vsk->remote_addr.svm_flags;
449
450 switch (sk->sk_type) {
451 case SOCK_DGRAM:
452 new_transport = transport_dgram;
453 break;
454 case SOCK_STREAM:
455 if (vsock_use_local_transport(remote_cid))
456 new_transport = transport_local;
457 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g ||
458 (remote_flags & VMADDR_FLAG_TO_HOST))
459 new_transport = transport_g2h;
460 else
461 new_transport = transport_h2g;
462 break;
463 default:
464 return -ESOCKTNOSUPPORT;
465 }
466
467 if (vsk->transport) {
468 if (vsk->transport == new_transport)
469 return 0;
470
471 /* transport->release() must be called with sock lock acquired.
472 * This path can only be taken during vsock_stream_connect(),
473 * where we have already held the sock lock.
474 * In the other cases, this function is called on a new socket
475 * which is not assigned to any transport.
476 */
477 vsk->transport->release(vsk);
478 vsock_deassign_transport(vsk);
479 }
480
481 /* We increase the module refcnt to prevent the transport unloading
482 * while there are open sockets assigned to it.
483 */
484 if (!new_transport || !try_module_get(new_transport->module))
485 return -ENODEV;
486
487 ret = new_transport->init(vsk, psk);
488 if (ret) {
489 module_put(new_transport->module);
490 return ret;
491 }
492
493 vsk->transport = new_transport;
494
495 return 0;
496 }
497 EXPORT_SYMBOL_GPL(vsock_assign_transport);
498
vsock_find_cid(unsigned int cid)499 bool vsock_find_cid(unsigned int cid)
500 {
501 if (transport_g2h && cid == transport_g2h->get_local_cid())
502 return true;
503
504 if (transport_h2g && cid == VMADDR_CID_HOST)
505 return true;
506
507 if (transport_local && cid == VMADDR_CID_LOCAL)
508 return true;
509
510 return false;
511 }
512 EXPORT_SYMBOL_GPL(vsock_find_cid);
513
vsock_dequeue_accept(struct sock * listener)514 static struct sock *vsock_dequeue_accept(struct sock *listener)
515 {
516 struct vsock_sock *vlistener;
517 struct vsock_sock *vconnected;
518
519 vlistener = vsock_sk(listener);
520
521 if (list_empty(&vlistener->accept_queue))
522 return NULL;
523
524 vconnected = list_entry(vlistener->accept_queue.next,
525 struct vsock_sock, accept_queue);
526
527 list_del_init(&vconnected->accept_queue);
528 sock_put(listener);
529 /* The caller will need a reference on the connected socket so we let
530 * it call sock_put().
531 */
532
533 return sk_vsock(vconnected);
534 }
535
vsock_is_accept_queue_empty(struct sock * sk)536 static bool vsock_is_accept_queue_empty(struct sock *sk)
537 {
538 struct vsock_sock *vsk = vsock_sk(sk);
539 return list_empty(&vsk->accept_queue);
540 }
541
vsock_is_pending(struct sock * sk)542 static bool vsock_is_pending(struct sock *sk)
543 {
544 struct vsock_sock *vsk = vsock_sk(sk);
545 return !list_empty(&vsk->pending_links);
546 }
547
vsock_send_shutdown(struct sock * sk,int mode)548 static int vsock_send_shutdown(struct sock *sk, int mode)
549 {
550 struct vsock_sock *vsk = vsock_sk(sk);
551
552 if (!vsk->transport)
553 return -ENODEV;
554
555 return vsk->transport->shutdown(vsk, mode);
556 }
557
vsock_pending_work(struct work_struct * work)558 static void vsock_pending_work(struct work_struct *work)
559 {
560 struct sock *sk;
561 struct sock *listener;
562 struct vsock_sock *vsk;
563 bool cleanup;
564
565 vsk = container_of(work, struct vsock_sock, pending_work.work);
566 sk = sk_vsock(vsk);
567 listener = vsk->listener;
568 cleanup = true;
569
570 lock_sock(listener);
571 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
572
573 if (vsock_is_pending(sk)) {
574 vsock_remove_pending(listener, sk);
575
576 sk_acceptq_removed(listener);
577 } else if (!vsk->rejected) {
578 /* We are not on the pending list and accept() did not reject
579 * us, so we must have been accepted by our user process. We
580 * just need to drop our references to the sockets and be on
581 * our way.
582 */
583 cleanup = false;
584 goto out;
585 }
586
587 /* We need to remove ourself from the global connected sockets list so
588 * incoming packets can't find this socket, and to reduce the reference
589 * count.
590 */
591 vsock_remove_connected(vsk);
592
593 sk->sk_state = TCP_CLOSE;
594
595 out:
596 release_sock(sk);
597 release_sock(listener);
598 if (cleanup)
599 sock_put(sk);
600
601 sock_put(sk);
602 sock_put(listener);
603 }
604
605 /**** SOCKET OPERATIONS ****/
606
__vsock_bind_stream(struct vsock_sock * vsk,struct sockaddr_vm * addr)607 static int __vsock_bind_stream(struct vsock_sock *vsk,
608 struct sockaddr_vm *addr)
609 {
610 static u32 port;
611 struct sockaddr_vm new_addr;
612
613 if (!port)
614 port = LAST_RESERVED_PORT + 1 +
615 prandom_u32_max(U32_MAX - LAST_RESERVED_PORT);
616
617 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
618
619 if (addr->svm_port == VMADDR_PORT_ANY) {
620 bool found = false;
621 unsigned int i;
622
623 for (i = 0; i < MAX_PORT_RETRIES; i++) {
624 if (port <= LAST_RESERVED_PORT)
625 port = LAST_RESERVED_PORT + 1;
626
627 new_addr.svm_port = port++;
628
629 if (!__vsock_find_bound_socket(&new_addr)) {
630 found = true;
631 break;
632 }
633 }
634
635 if (!found)
636 return -EADDRNOTAVAIL;
637 } else {
638 /* If port is in reserved range, ensure caller
639 * has necessary privileges.
640 */
641 if (addr->svm_port <= LAST_RESERVED_PORT &&
642 !capable(CAP_NET_BIND_SERVICE)) {
643 return -EACCES;
644 }
645
646 if (__vsock_find_bound_socket(&new_addr))
647 return -EADDRINUSE;
648 }
649
650 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
651
652 /* Remove stream sockets from the unbound list and add them to the hash
653 * table for easy lookup by its address. The unbound list is simply an
654 * extra entry at the end of the hash table, a trick used by AF_UNIX.
655 */
656 __vsock_remove_bound(vsk);
657 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
658
659 return 0;
660 }
661
__vsock_bind_dgram(struct vsock_sock * vsk,struct sockaddr_vm * addr)662 static int __vsock_bind_dgram(struct vsock_sock *vsk,
663 struct sockaddr_vm *addr)
664 {
665 return vsk->transport->dgram_bind(vsk, addr);
666 }
667
__vsock_bind(struct sock * sk,struct sockaddr_vm * addr)668 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
669 {
670 struct vsock_sock *vsk = vsock_sk(sk);
671 int retval;
672
673 /* First ensure this socket isn't already bound. */
674 if (vsock_addr_bound(&vsk->local_addr))
675 return -EINVAL;
676
677 /* Now bind to the provided address or select appropriate values if
678 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that
679 * like AF_INET prevents binding to a non-local IP address (in most
680 * cases), we only allow binding to a local CID.
681 */
682 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid))
683 return -EADDRNOTAVAIL;
684
685 switch (sk->sk_socket->type) {
686 case SOCK_STREAM:
687 spin_lock_bh(&vsock_table_lock);
688 retval = __vsock_bind_stream(vsk, addr);
689 spin_unlock_bh(&vsock_table_lock);
690 break;
691
692 case SOCK_DGRAM:
693 retval = __vsock_bind_dgram(vsk, addr);
694 break;
695
696 default:
697 retval = -EINVAL;
698 break;
699 }
700
701 return retval;
702 }
703
704 static void vsock_connect_timeout(struct work_struct *work);
705
__vsock_create(struct net * net,struct socket * sock,struct sock * parent,gfp_t priority,unsigned short type,int kern)706 static struct sock *__vsock_create(struct net *net,
707 struct socket *sock,
708 struct sock *parent,
709 gfp_t priority,
710 unsigned short type,
711 int kern)
712 {
713 struct sock *sk;
714 struct vsock_sock *psk;
715 struct vsock_sock *vsk;
716
717 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern);
718 if (!sk)
719 return NULL;
720
721 sock_init_data(sock, sk);
722
723 /* sk->sk_type is normally set in sock_init_data, but only if sock is
724 * non-NULL. We make sure that our sockets always have a type by
725 * setting it here if needed.
726 */
727 if (!sock)
728 sk->sk_type = type;
729
730 vsk = vsock_sk(sk);
731 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
732 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
733
734 sk->sk_destruct = vsock_sk_destruct;
735 sk->sk_backlog_rcv = vsock_queue_rcv_skb;
736 sock_reset_flag(sk, SOCK_DONE);
737
738 INIT_LIST_HEAD(&vsk->bound_table);
739 INIT_LIST_HEAD(&vsk->connected_table);
740 vsk->listener = NULL;
741 INIT_LIST_HEAD(&vsk->pending_links);
742 INIT_LIST_HEAD(&vsk->accept_queue);
743 vsk->rejected = false;
744 vsk->sent_request = false;
745 vsk->ignore_connecting_rst = false;
746 vsk->peer_shutdown = 0;
747 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout);
748 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work);
749
750 psk = parent ? vsock_sk(parent) : NULL;
751 if (parent) {
752 vsk->trusted = psk->trusted;
753 vsk->owner = get_cred(psk->owner);
754 vsk->connect_timeout = psk->connect_timeout;
755 vsk->buffer_size = psk->buffer_size;
756 vsk->buffer_min_size = psk->buffer_min_size;
757 vsk->buffer_max_size = psk->buffer_max_size;
758 security_sk_clone(parent, sk);
759 } else {
760 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN);
761 vsk->owner = get_current_cred();
762 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
763 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE;
764 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE;
765 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE;
766 }
767
768 return sk;
769 }
770
__vsock_release(struct sock * sk,int level)771 static void __vsock_release(struct sock *sk, int level)
772 {
773 if (sk) {
774 struct sock *pending;
775 struct vsock_sock *vsk;
776
777 vsk = vsock_sk(sk);
778 pending = NULL; /* Compiler warning. */
779
780 /* When "level" is SINGLE_DEPTH_NESTING, use the nested
781 * version to avoid the warning "possible recursive locking
782 * detected". When "level" is 0, lock_sock_nested(sk, level)
783 * is the same as lock_sock(sk).
784 */
785 lock_sock_nested(sk, level);
786
787 if (vsk->transport)
788 vsk->transport->release(vsk);
789 else if (sk->sk_type == SOCK_STREAM)
790 vsock_remove_sock(vsk);
791
792 sock_orphan(sk);
793 sk->sk_shutdown = SHUTDOWN_MASK;
794
795 skb_queue_purge(&sk->sk_receive_queue);
796
797 /* Clean up any sockets that never were accepted. */
798 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
799 __vsock_release(pending, SINGLE_DEPTH_NESTING);
800 sock_put(pending);
801 }
802
803 release_sock(sk);
804 sock_put(sk);
805 }
806 }
807
vsock_sk_destruct(struct sock * sk)808 static void vsock_sk_destruct(struct sock *sk)
809 {
810 struct vsock_sock *vsk = vsock_sk(sk);
811
812 vsock_deassign_transport(vsk);
813
814 /* When clearing these addresses, there's no need to set the family and
815 * possibly register the address family with the kernel.
816 */
817 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
818 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
819
820 put_cred(vsk->owner);
821 }
822
vsock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)823 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
824 {
825 int err;
826
827 err = sock_queue_rcv_skb(sk, skb);
828 if (err)
829 kfree_skb(skb);
830
831 return err;
832 }
833
vsock_create_connected(struct sock * parent)834 struct sock *vsock_create_connected(struct sock *parent)
835 {
836 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL,
837 parent->sk_type, 0);
838 }
839 EXPORT_SYMBOL_GPL(vsock_create_connected);
840
vsock_stream_has_data(struct vsock_sock * vsk)841 s64 vsock_stream_has_data(struct vsock_sock *vsk)
842 {
843 return vsk->transport->stream_has_data(vsk);
844 }
845 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
846
vsock_stream_has_space(struct vsock_sock * vsk)847 s64 vsock_stream_has_space(struct vsock_sock *vsk)
848 {
849 return vsk->transport->stream_has_space(vsk);
850 }
851 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
852
vsock_release(struct socket * sock)853 static int vsock_release(struct socket *sock)
854 {
855 __vsock_release(sock->sk, 0);
856 sock->sk = NULL;
857 sock->state = SS_FREE;
858
859 return 0;
860 }
861
862 static int
vsock_bind(struct socket * sock,struct sockaddr * addr,int addr_len)863 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
864 {
865 int err;
866 struct sock *sk;
867 struct sockaddr_vm *vm_addr;
868
869 sk = sock->sk;
870
871 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
872 return -EINVAL;
873
874 lock_sock(sk);
875 err = __vsock_bind(sk, vm_addr);
876 release_sock(sk);
877
878 return err;
879 }
880
vsock_getname(struct socket * sock,struct sockaddr * addr,int peer)881 static int vsock_getname(struct socket *sock,
882 struct sockaddr *addr, int peer)
883 {
884 int err;
885 struct sock *sk;
886 struct vsock_sock *vsk;
887 struct sockaddr_vm *vm_addr;
888
889 sk = sock->sk;
890 vsk = vsock_sk(sk);
891 err = 0;
892
893 lock_sock(sk);
894
895 if (peer) {
896 if (sock->state != SS_CONNECTED) {
897 err = -ENOTCONN;
898 goto out;
899 }
900 vm_addr = &vsk->remote_addr;
901 } else {
902 vm_addr = &vsk->local_addr;
903 }
904
905 if (!vm_addr) {
906 err = -EINVAL;
907 goto out;
908 }
909
910 /* sys_getsockname() and sys_getpeername() pass us a
911 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately
912 * that macro is defined in socket.c instead of .h, so we hardcode its
913 * value here.
914 */
915 BUILD_BUG_ON(sizeof(*vm_addr) > 128);
916 memcpy(addr, vm_addr, sizeof(*vm_addr));
917 err = sizeof(*vm_addr);
918
919 out:
920 release_sock(sk);
921 return err;
922 }
923
vsock_shutdown(struct socket * sock,int mode)924 static int vsock_shutdown(struct socket *sock, int mode)
925 {
926 int err;
927 struct sock *sk;
928
929 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
930 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
931 * here like the other address families do. Note also that the
932 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
933 * which is what we want.
934 */
935 mode++;
936
937 if ((mode & ~SHUTDOWN_MASK) || !mode)
938 return -EINVAL;
939
940 /* If this is a STREAM socket and it is not connected then bail out
941 * immediately. If it is a DGRAM socket then we must first kick the
942 * socket so that it wakes up from any sleeping calls, for example
943 * recv(), and then afterwards return the error.
944 */
945
946 sk = sock->sk;
947
948 lock_sock(sk);
949 if (sock->state == SS_UNCONNECTED) {
950 err = -ENOTCONN;
951 if (sk->sk_type == SOCK_STREAM)
952 goto out;
953 } else {
954 sock->state = SS_DISCONNECTING;
955 err = 0;
956 }
957
958 /* Receive and send shutdowns are treated alike. */
959 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
960 if (mode) {
961 sk->sk_shutdown |= mode;
962 sk->sk_state_change(sk);
963
964 if (sk->sk_type == SOCK_STREAM) {
965 sock_reset_flag(sk, SOCK_DONE);
966 vsock_send_shutdown(sk, mode);
967 }
968 }
969
970 out:
971 release_sock(sk);
972 return err;
973 }
974
vsock_poll(struct file * file,struct socket * sock,poll_table * wait)975 static __poll_t vsock_poll(struct file *file, struct socket *sock,
976 poll_table *wait)
977 {
978 struct sock *sk;
979 __poll_t mask;
980 struct vsock_sock *vsk;
981
982 sk = sock->sk;
983 vsk = vsock_sk(sk);
984
985 poll_wait(file, sk_sleep(sk), wait);
986 mask = 0;
987
988 if (sk->sk_err)
989 /* Signify that there has been an error on this socket. */
990 mask |= EPOLLERR;
991
992 /* INET sockets treat local write shutdown and peer write shutdown as a
993 * case of EPOLLHUP set.
994 */
995 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
996 ((sk->sk_shutdown & SEND_SHUTDOWN) &&
997 (vsk->peer_shutdown & SEND_SHUTDOWN))) {
998 mask |= EPOLLHUP;
999 }
1000
1001 if (sk->sk_shutdown & RCV_SHUTDOWN ||
1002 vsk->peer_shutdown & SEND_SHUTDOWN) {
1003 mask |= EPOLLRDHUP;
1004 }
1005
1006 if (sock->type == SOCK_DGRAM) {
1007 /* For datagram sockets we can read if there is something in
1008 * the queue and write as long as the socket isn't shutdown for
1009 * sending.
1010 */
1011 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1012 (sk->sk_shutdown & RCV_SHUTDOWN)) {
1013 mask |= EPOLLIN | EPOLLRDNORM;
1014 }
1015
1016 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1017 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1018
1019 } else if (sock->type == SOCK_STREAM) {
1020 const struct vsock_transport *transport;
1021
1022 lock_sock(sk);
1023
1024 transport = vsk->transport;
1025
1026 /* Listening sockets that have connections in their accept
1027 * queue can be read.
1028 */
1029 if (sk->sk_state == TCP_LISTEN
1030 && !vsock_is_accept_queue_empty(sk))
1031 mask |= EPOLLIN | EPOLLRDNORM;
1032
1033 /* If there is something in the queue then we can read. */
1034 if (transport && transport->stream_is_active(vsk) &&
1035 !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1036 bool data_ready_now = false;
1037 int ret = transport->notify_poll_in(
1038 vsk, 1, &data_ready_now);
1039 if (ret < 0) {
1040 mask |= EPOLLERR;
1041 } else {
1042 if (data_ready_now)
1043 mask |= EPOLLIN | EPOLLRDNORM;
1044
1045 }
1046 }
1047
1048 /* Sockets whose connections have been closed, reset, or
1049 * terminated should also be considered read, and we check the
1050 * shutdown flag for that.
1051 */
1052 if (sk->sk_shutdown & RCV_SHUTDOWN ||
1053 vsk->peer_shutdown & SEND_SHUTDOWN) {
1054 mask |= EPOLLIN | EPOLLRDNORM;
1055 }
1056
1057 /* Connected sockets that can produce data can be written. */
1058 if (transport && sk->sk_state == TCP_ESTABLISHED) {
1059 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1060 bool space_avail_now = false;
1061 int ret = transport->notify_poll_out(
1062 vsk, 1, &space_avail_now);
1063 if (ret < 0) {
1064 mask |= EPOLLERR;
1065 } else {
1066 if (space_avail_now)
1067 /* Remove EPOLLWRBAND since INET
1068 * sockets are not setting it.
1069 */
1070 mask |= EPOLLOUT | EPOLLWRNORM;
1071
1072 }
1073 }
1074 }
1075
1076 /* Simulate INET socket poll behaviors, which sets
1077 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read,
1078 * but local send is not shutdown.
1079 */
1080 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) {
1081 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1082 mask |= EPOLLOUT | EPOLLWRNORM;
1083
1084 }
1085
1086 release_sock(sk);
1087 }
1088
1089 return mask;
1090 }
1091
vsock_dgram_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)1092 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
1093 size_t len)
1094 {
1095 int err;
1096 struct sock *sk;
1097 struct vsock_sock *vsk;
1098 struct sockaddr_vm *remote_addr;
1099 const struct vsock_transport *transport;
1100
1101 if (msg->msg_flags & MSG_OOB)
1102 return -EOPNOTSUPP;
1103
1104 /* For now, MSG_DONTWAIT is always assumed... */
1105 err = 0;
1106 sk = sock->sk;
1107 vsk = vsock_sk(sk);
1108
1109 lock_sock(sk);
1110
1111 transport = vsk->transport;
1112
1113 err = vsock_auto_bind(vsk);
1114 if (err)
1115 goto out;
1116
1117
1118 /* If the provided message contains an address, use that. Otherwise
1119 * fall back on the socket's remote handle (if it has been connected).
1120 */
1121 if (msg->msg_name &&
1122 vsock_addr_cast(msg->msg_name, msg->msg_namelen,
1123 &remote_addr) == 0) {
1124 /* Ensure this address is of the right type and is a valid
1125 * destination.
1126 */
1127
1128 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1129 remote_addr->svm_cid = transport->get_local_cid();
1130
1131 if (!vsock_addr_bound(remote_addr)) {
1132 err = -EINVAL;
1133 goto out;
1134 }
1135 } else if (sock->state == SS_CONNECTED) {
1136 remote_addr = &vsk->remote_addr;
1137
1138 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1139 remote_addr->svm_cid = transport->get_local_cid();
1140
1141 /* XXX Should connect() or this function ensure remote_addr is
1142 * bound?
1143 */
1144 if (!vsock_addr_bound(&vsk->remote_addr)) {
1145 err = -EINVAL;
1146 goto out;
1147 }
1148 } else {
1149 err = -EINVAL;
1150 goto out;
1151 }
1152
1153 if (!transport->dgram_allow(remote_addr->svm_cid,
1154 remote_addr->svm_port)) {
1155 err = -EINVAL;
1156 goto out;
1157 }
1158
1159 err = transport->dgram_enqueue(vsk, remote_addr, msg, len);
1160
1161 out:
1162 release_sock(sk);
1163 return err;
1164 }
1165
vsock_dgram_connect(struct socket * sock,struct sockaddr * addr,int addr_len,int flags)1166 static int vsock_dgram_connect(struct socket *sock,
1167 struct sockaddr *addr, int addr_len, int flags)
1168 {
1169 int err;
1170 struct sock *sk;
1171 struct vsock_sock *vsk;
1172 struct sockaddr_vm *remote_addr;
1173
1174 sk = sock->sk;
1175 vsk = vsock_sk(sk);
1176
1177 err = vsock_addr_cast(addr, addr_len, &remote_addr);
1178 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1179 lock_sock(sk);
1180 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1181 VMADDR_PORT_ANY);
1182 sock->state = SS_UNCONNECTED;
1183 release_sock(sk);
1184 return 0;
1185 } else if (err != 0)
1186 return -EINVAL;
1187
1188 lock_sock(sk);
1189
1190 err = vsock_auto_bind(vsk);
1191 if (err)
1192 goto out;
1193
1194 if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
1195 remote_addr->svm_port)) {
1196 err = -EINVAL;
1197 goto out;
1198 }
1199
1200 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1201 sock->state = SS_CONNECTED;
1202
1203 out:
1204 release_sock(sk);
1205 return err;
1206 }
1207
vsock_dgram_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)1208 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
1209 size_t len, int flags)
1210 {
1211 struct vsock_sock *vsk = vsock_sk(sock->sk);
1212
1213 return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
1214 }
1215
1216 static const struct proto_ops vsock_dgram_ops = {
1217 .family = PF_VSOCK,
1218 .owner = THIS_MODULE,
1219 .release = vsock_release,
1220 .bind = vsock_bind,
1221 .connect = vsock_dgram_connect,
1222 .socketpair = sock_no_socketpair,
1223 .accept = sock_no_accept,
1224 .getname = vsock_getname,
1225 .poll = vsock_poll,
1226 .ioctl = sock_no_ioctl,
1227 .listen = sock_no_listen,
1228 .shutdown = vsock_shutdown,
1229 .sendmsg = vsock_dgram_sendmsg,
1230 .recvmsg = vsock_dgram_recvmsg,
1231 .mmap = sock_no_mmap,
1232 .sendpage = sock_no_sendpage,
1233 };
1234
vsock_transport_cancel_pkt(struct vsock_sock * vsk)1235 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
1236 {
1237 const struct vsock_transport *transport = vsk->transport;
1238
1239 if (!transport || !transport->cancel_pkt)
1240 return -EOPNOTSUPP;
1241
1242 return transport->cancel_pkt(vsk);
1243 }
1244
vsock_connect_timeout(struct work_struct * work)1245 static void vsock_connect_timeout(struct work_struct *work)
1246 {
1247 struct sock *sk;
1248 struct vsock_sock *vsk;
1249
1250 vsk = container_of(work, struct vsock_sock, connect_work.work);
1251 sk = sk_vsock(vsk);
1252
1253 lock_sock(sk);
1254 if (sk->sk_state == TCP_SYN_SENT &&
1255 (sk->sk_shutdown != SHUTDOWN_MASK)) {
1256 sk->sk_state = TCP_CLOSE;
1257 sk->sk_err = ETIMEDOUT;
1258 sk->sk_error_report(sk);
1259 vsock_transport_cancel_pkt(vsk);
1260 }
1261 release_sock(sk);
1262
1263 sock_put(sk);
1264 }
1265
vsock_stream_connect(struct socket * sock,struct sockaddr * addr,int addr_len,int flags)1266 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1267 int addr_len, int flags)
1268 {
1269 int err;
1270 struct sock *sk;
1271 struct vsock_sock *vsk;
1272 const struct vsock_transport *transport;
1273 struct sockaddr_vm *remote_addr;
1274 long timeout;
1275 DEFINE_WAIT(wait);
1276
1277 err = 0;
1278 sk = sock->sk;
1279 vsk = vsock_sk(sk);
1280
1281 lock_sock(sk);
1282
1283 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1284 switch (sock->state) {
1285 case SS_CONNECTED:
1286 err = -EISCONN;
1287 goto out;
1288 case SS_DISCONNECTING:
1289 err = -EINVAL;
1290 goto out;
1291 case SS_CONNECTING:
1292 /* This continues on so we can move sock into the SS_CONNECTED
1293 * state once the connection has completed (at which point err
1294 * will be set to zero also). Otherwise, we will either wait
1295 * for the connection or return -EALREADY should this be a
1296 * non-blocking call.
1297 */
1298 err = -EALREADY;
1299 break;
1300 default:
1301 if ((sk->sk_state == TCP_LISTEN) ||
1302 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1303 err = -EINVAL;
1304 goto out;
1305 }
1306
1307 /* Set the remote address that we are connecting to. */
1308 memcpy(&vsk->remote_addr, remote_addr,
1309 sizeof(vsk->remote_addr));
1310
1311 err = vsock_assign_transport(vsk, NULL);
1312 if (err)
1313 goto out;
1314
1315 transport = vsk->transport;
1316
1317 /* The hypervisor and well-known contexts do not have socket
1318 * endpoints.
1319 */
1320 if (!transport ||
1321 !transport->stream_allow(remote_addr->svm_cid,
1322 remote_addr->svm_port)) {
1323 err = -ENETUNREACH;
1324 goto out;
1325 }
1326
1327 err = vsock_auto_bind(vsk);
1328 if (err)
1329 goto out;
1330
1331 sk->sk_state = TCP_SYN_SENT;
1332
1333 err = transport->connect(vsk);
1334 if (err < 0)
1335 goto out;
1336
1337 /* Mark sock as connecting and set the error code to in
1338 * progress in case this is a non-blocking connect.
1339 */
1340 sock->state = SS_CONNECTING;
1341 err = -EINPROGRESS;
1342 }
1343
1344 /* The receive path will handle all communication until we are able to
1345 * enter the connected state. Here we wait for the connection to be
1346 * completed or a notification of an error.
1347 */
1348 timeout = vsk->connect_timeout;
1349 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1350
1351 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
1352 if (flags & O_NONBLOCK) {
1353 /* If we're not going to block, we schedule a timeout
1354 * function to generate a timeout on the connection
1355 * attempt, in case the peer doesn't respond in a
1356 * timely manner. We hold on to the socket until the
1357 * timeout fires.
1358 */
1359 sock_hold(sk);
1360 schedule_delayed_work(&vsk->connect_work, timeout);
1361
1362 /* Skip ahead to preserve error code set above. */
1363 goto out_wait;
1364 }
1365
1366 release_sock(sk);
1367 timeout = schedule_timeout(timeout);
1368 lock_sock(sk);
1369
1370 if (signal_pending(current)) {
1371 err = sock_intr_errno(timeout);
1372 sk->sk_state = TCP_CLOSE;
1373 sock->state = SS_UNCONNECTED;
1374 vsock_transport_cancel_pkt(vsk);
1375 goto out_wait;
1376 } else if (timeout == 0) {
1377 err = -ETIMEDOUT;
1378 sk->sk_state = TCP_CLOSE;
1379 sock->state = SS_UNCONNECTED;
1380 vsock_transport_cancel_pkt(vsk);
1381 goto out_wait;
1382 }
1383
1384 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1385 }
1386
1387 if (sk->sk_err) {
1388 err = -sk->sk_err;
1389 sk->sk_state = TCP_CLOSE;
1390 sock->state = SS_UNCONNECTED;
1391 } else {
1392 err = 0;
1393 }
1394
1395 out_wait:
1396 finish_wait(sk_sleep(sk), &wait);
1397 out:
1398 release_sock(sk);
1399 return err;
1400 }
1401
vsock_accept(struct socket * sock,struct socket * newsock,int flags,bool kern)1402 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
1403 bool kern)
1404 {
1405 struct sock *listener;
1406 int err;
1407 struct sock *connected;
1408 struct vsock_sock *vconnected;
1409 long timeout;
1410 DEFINE_WAIT(wait);
1411
1412 err = 0;
1413 listener = sock->sk;
1414
1415 lock_sock(listener);
1416
1417 if (sock->type != SOCK_STREAM) {
1418 err = -EOPNOTSUPP;
1419 goto out;
1420 }
1421
1422 if (listener->sk_state != TCP_LISTEN) {
1423 err = -EINVAL;
1424 goto out;
1425 }
1426
1427 /* Wait for children sockets to appear; these are the new sockets
1428 * created upon connection establishment.
1429 */
1430 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK);
1431 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1432
1433 while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1434 listener->sk_err == 0) {
1435 release_sock(listener);
1436 timeout = schedule_timeout(timeout);
1437 finish_wait(sk_sleep(listener), &wait);
1438 lock_sock(listener);
1439
1440 if (signal_pending(current)) {
1441 err = sock_intr_errno(timeout);
1442 goto out;
1443 } else if (timeout == 0) {
1444 err = -EAGAIN;
1445 goto out;
1446 }
1447
1448 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1449 }
1450 finish_wait(sk_sleep(listener), &wait);
1451
1452 if (listener->sk_err)
1453 err = -listener->sk_err;
1454
1455 if (connected) {
1456 sk_acceptq_removed(listener);
1457
1458 lock_sock_nested(connected, SINGLE_DEPTH_NESTING);
1459 vconnected = vsock_sk(connected);
1460
1461 /* If the listener socket has received an error, then we should
1462 * reject this socket and return. Note that we simply mark the
1463 * socket rejected, drop our reference, and let the cleanup
1464 * function handle the cleanup; the fact that we found it in
1465 * the listener's accept queue guarantees that the cleanup
1466 * function hasn't run yet.
1467 */
1468 if (err) {
1469 vconnected->rejected = true;
1470 } else {
1471 newsock->state = SS_CONNECTED;
1472 sock_graft(connected, newsock);
1473 }
1474
1475 release_sock(connected);
1476 sock_put(connected);
1477 }
1478
1479 out:
1480 release_sock(listener);
1481 return err;
1482 }
1483
vsock_listen(struct socket * sock,int backlog)1484 static int vsock_listen(struct socket *sock, int backlog)
1485 {
1486 int err;
1487 struct sock *sk;
1488 struct vsock_sock *vsk;
1489
1490 sk = sock->sk;
1491
1492 lock_sock(sk);
1493
1494 if (sock->type != SOCK_STREAM) {
1495 err = -EOPNOTSUPP;
1496 goto out;
1497 }
1498
1499 if (sock->state != SS_UNCONNECTED) {
1500 err = -EINVAL;
1501 goto out;
1502 }
1503
1504 vsk = vsock_sk(sk);
1505
1506 if (!vsock_addr_bound(&vsk->local_addr)) {
1507 err = -EINVAL;
1508 goto out;
1509 }
1510
1511 sk->sk_max_ack_backlog = backlog;
1512 sk->sk_state = TCP_LISTEN;
1513
1514 err = 0;
1515
1516 out:
1517 release_sock(sk);
1518 return err;
1519 }
1520
vsock_update_buffer_size(struct vsock_sock * vsk,const struct vsock_transport * transport,u64 val)1521 static void vsock_update_buffer_size(struct vsock_sock *vsk,
1522 const struct vsock_transport *transport,
1523 u64 val)
1524 {
1525 if (val > vsk->buffer_max_size)
1526 val = vsk->buffer_max_size;
1527
1528 if (val < vsk->buffer_min_size)
1529 val = vsk->buffer_min_size;
1530
1531 if (val != vsk->buffer_size &&
1532 transport && transport->notify_buffer_size)
1533 transport->notify_buffer_size(vsk, &val);
1534
1535 vsk->buffer_size = val;
1536 }
1537
vsock_stream_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1538 static int vsock_stream_setsockopt(struct socket *sock,
1539 int level,
1540 int optname,
1541 sockptr_t optval,
1542 unsigned int optlen)
1543 {
1544 int err;
1545 struct sock *sk;
1546 struct vsock_sock *vsk;
1547 const struct vsock_transport *transport;
1548 u64 val;
1549
1550 if (level != AF_VSOCK)
1551 return -ENOPROTOOPT;
1552
1553 #define COPY_IN(_v) \
1554 do { \
1555 if (optlen < sizeof(_v)) { \
1556 err = -EINVAL; \
1557 goto exit; \
1558 } \
1559 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \
1560 err = -EFAULT; \
1561 goto exit; \
1562 } \
1563 } while (0)
1564
1565 err = 0;
1566 sk = sock->sk;
1567 vsk = vsock_sk(sk);
1568
1569 lock_sock(sk);
1570
1571 transport = vsk->transport;
1572
1573 switch (optname) {
1574 case SO_VM_SOCKETS_BUFFER_SIZE:
1575 COPY_IN(val);
1576 vsock_update_buffer_size(vsk, transport, val);
1577 break;
1578
1579 case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1580 COPY_IN(val);
1581 vsk->buffer_max_size = val;
1582 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1583 break;
1584
1585 case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1586 COPY_IN(val);
1587 vsk->buffer_min_size = val;
1588 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1589 break;
1590
1591 case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1592 struct __kernel_old_timeval tv;
1593 COPY_IN(tv);
1594 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1595 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1596 vsk->connect_timeout = tv.tv_sec * HZ +
1597 DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1598 if (vsk->connect_timeout == 0)
1599 vsk->connect_timeout =
1600 VSOCK_DEFAULT_CONNECT_TIMEOUT;
1601
1602 } else {
1603 err = -ERANGE;
1604 }
1605 break;
1606 }
1607
1608 default:
1609 err = -ENOPROTOOPT;
1610 break;
1611 }
1612
1613 #undef COPY_IN
1614
1615 exit:
1616 release_sock(sk);
1617 return err;
1618 }
1619
vsock_stream_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)1620 static int vsock_stream_getsockopt(struct socket *sock,
1621 int level, int optname,
1622 char __user *optval,
1623 int __user *optlen)
1624 {
1625 int err;
1626 int len;
1627 struct sock *sk;
1628 struct vsock_sock *vsk;
1629 u64 val;
1630
1631 if (level != AF_VSOCK)
1632 return -ENOPROTOOPT;
1633
1634 err = get_user(len, optlen);
1635 if (err != 0)
1636 return err;
1637
1638 #define COPY_OUT(_v) \
1639 do { \
1640 if (len < sizeof(_v)) \
1641 return -EINVAL; \
1642 \
1643 len = sizeof(_v); \
1644 if (copy_to_user(optval, &_v, len) != 0) \
1645 return -EFAULT; \
1646 \
1647 } while (0)
1648
1649 err = 0;
1650 sk = sock->sk;
1651 vsk = vsock_sk(sk);
1652
1653 switch (optname) {
1654 case SO_VM_SOCKETS_BUFFER_SIZE:
1655 val = vsk->buffer_size;
1656 COPY_OUT(val);
1657 break;
1658
1659 case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1660 val = vsk->buffer_max_size;
1661 COPY_OUT(val);
1662 break;
1663
1664 case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1665 val = vsk->buffer_min_size;
1666 COPY_OUT(val);
1667 break;
1668
1669 case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1670 struct __kernel_old_timeval tv;
1671 tv.tv_sec = vsk->connect_timeout / HZ;
1672 tv.tv_usec =
1673 (vsk->connect_timeout -
1674 tv.tv_sec * HZ) * (1000000 / HZ);
1675 COPY_OUT(tv);
1676 break;
1677 }
1678 default:
1679 return -ENOPROTOOPT;
1680 }
1681
1682 err = put_user(len, optlen);
1683 if (err != 0)
1684 return -EFAULT;
1685
1686 #undef COPY_OUT
1687
1688 return 0;
1689 }
1690
vsock_stream_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)1691 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
1692 size_t len)
1693 {
1694 struct sock *sk;
1695 struct vsock_sock *vsk;
1696 const struct vsock_transport *transport;
1697 ssize_t total_written;
1698 long timeout;
1699 int err;
1700 struct vsock_transport_send_notify_data send_data;
1701 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1702
1703 sk = sock->sk;
1704 vsk = vsock_sk(sk);
1705 total_written = 0;
1706 err = 0;
1707
1708 if (msg->msg_flags & MSG_OOB)
1709 return -EOPNOTSUPP;
1710
1711 lock_sock(sk);
1712
1713 transport = vsk->transport;
1714
1715 /* Callers should not provide a destination with stream sockets. */
1716 if (msg->msg_namelen) {
1717 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
1718 goto out;
1719 }
1720
1721 /* Send data only if both sides are not shutdown in the direction. */
1722 if (sk->sk_shutdown & SEND_SHUTDOWN ||
1723 vsk->peer_shutdown & RCV_SHUTDOWN) {
1724 err = -EPIPE;
1725 goto out;
1726 }
1727
1728 if (!transport || sk->sk_state != TCP_ESTABLISHED ||
1729 !vsock_addr_bound(&vsk->local_addr)) {
1730 err = -ENOTCONN;
1731 goto out;
1732 }
1733
1734 if (!vsock_addr_bound(&vsk->remote_addr)) {
1735 err = -EDESTADDRREQ;
1736 goto out;
1737 }
1738
1739 /* Wait for room in the produce queue to enqueue our user's data. */
1740 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1741
1742 err = transport->notify_send_init(vsk, &send_data);
1743 if (err < 0)
1744 goto out;
1745
1746 while (total_written < len) {
1747 ssize_t written;
1748
1749 add_wait_queue(sk_sleep(sk), &wait);
1750 while (vsock_stream_has_space(vsk) == 0 &&
1751 sk->sk_err == 0 &&
1752 !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1753 !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1754
1755 /* Don't wait for non-blocking sockets. */
1756 if (timeout == 0) {
1757 err = -EAGAIN;
1758 remove_wait_queue(sk_sleep(sk), &wait);
1759 goto out_err;
1760 }
1761
1762 err = transport->notify_send_pre_block(vsk, &send_data);
1763 if (err < 0) {
1764 remove_wait_queue(sk_sleep(sk), &wait);
1765 goto out_err;
1766 }
1767
1768 release_sock(sk);
1769 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
1770 lock_sock(sk);
1771 if (signal_pending(current)) {
1772 err = sock_intr_errno(timeout);
1773 remove_wait_queue(sk_sleep(sk), &wait);
1774 goto out_err;
1775 } else if (timeout == 0) {
1776 err = -EAGAIN;
1777 remove_wait_queue(sk_sleep(sk), &wait);
1778 goto out_err;
1779 }
1780 }
1781 remove_wait_queue(sk_sleep(sk), &wait);
1782
1783 /* These checks occur both as part of and after the loop
1784 * conditional since we need to check before and after
1785 * sleeping.
1786 */
1787 if (sk->sk_err) {
1788 err = -sk->sk_err;
1789 goto out_err;
1790 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1791 (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1792 err = -EPIPE;
1793 goto out_err;
1794 }
1795
1796 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1797 if (err < 0)
1798 goto out_err;
1799
1800 /* Note that enqueue will only write as many bytes as are free
1801 * in the produce queue, so we don't need to ensure len is
1802 * smaller than the queue size. It is the caller's
1803 * responsibility to check how many bytes we were able to send.
1804 */
1805
1806 written = transport->stream_enqueue(
1807 vsk, msg,
1808 len - total_written);
1809 if (written < 0) {
1810 err = -ENOMEM;
1811 goto out_err;
1812 }
1813
1814 total_written += written;
1815
1816 err = transport->notify_send_post_enqueue(
1817 vsk, written, &send_data);
1818 if (err < 0)
1819 goto out_err;
1820
1821 }
1822
1823 out_err:
1824 if (total_written > 0)
1825 err = total_written;
1826 out:
1827 release_sock(sk);
1828 return err;
1829 }
1830
1831
1832 static int
vsock_stream_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)1833 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1834 int flags)
1835 {
1836 struct sock *sk;
1837 struct vsock_sock *vsk;
1838 const struct vsock_transport *transport;
1839 int err;
1840 size_t target;
1841 ssize_t copied;
1842 long timeout;
1843 struct vsock_transport_recv_notify_data recv_data;
1844
1845 DEFINE_WAIT(wait);
1846
1847 sk = sock->sk;
1848 vsk = vsock_sk(sk);
1849 err = 0;
1850
1851 lock_sock(sk);
1852
1853 transport = vsk->transport;
1854
1855 if (!transport || sk->sk_state != TCP_ESTABLISHED) {
1856 /* Recvmsg is supposed to return 0 if a peer performs an
1857 * orderly shutdown. Differentiate between that case and when a
1858 * peer has not connected or a local shutdown occurred with the
1859 * SOCK_DONE flag.
1860 */
1861 if (sock_flag(sk, SOCK_DONE))
1862 err = 0;
1863 else
1864 err = -ENOTCONN;
1865
1866 goto out;
1867 }
1868
1869 if (flags & MSG_OOB) {
1870 err = -EOPNOTSUPP;
1871 goto out;
1872 }
1873
1874 /* We don't check peer_shutdown flag here since peer may actually shut
1875 * down, but there can be data in the queue that a local socket can
1876 * receive.
1877 */
1878 if (sk->sk_shutdown & RCV_SHUTDOWN) {
1879 err = 0;
1880 goto out;
1881 }
1882
1883 /* It is valid on Linux to pass in a zero-length receive buffer. This
1884 * is not an error. We may as well bail out now.
1885 */
1886 if (!len) {
1887 err = 0;
1888 goto out;
1889 }
1890
1891 /* We must not copy less than target bytes into the user's buffer
1892 * before returning successfully, so we wait for the consume queue to
1893 * have that much data to consume before dequeueing. Note that this
1894 * makes it impossible to handle cases where target is greater than the
1895 * queue size.
1896 */
1897 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1898 if (target >= transport->stream_rcvhiwat(vsk)) {
1899 err = -ENOMEM;
1900 goto out;
1901 }
1902 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1903 copied = 0;
1904
1905 err = transport->notify_recv_init(vsk, target, &recv_data);
1906 if (err < 0)
1907 goto out;
1908
1909
1910 while (1) {
1911 s64 ready;
1912
1913 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1914 ready = vsock_stream_has_data(vsk);
1915
1916 if (ready == 0) {
1917 if (sk->sk_err != 0 ||
1918 (sk->sk_shutdown & RCV_SHUTDOWN) ||
1919 (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1920 finish_wait(sk_sleep(sk), &wait);
1921 break;
1922 }
1923 /* Don't wait for non-blocking sockets. */
1924 if (timeout == 0) {
1925 err = -EAGAIN;
1926 finish_wait(sk_sleep(sk), &wait);
1927 break;
1928 }
1929
1930 err = transport->notify_recv_pre_block(
1931 vsk, target, &recv_data);
1932 if (err < 0) {
1933 finish_wait(sk_sleep(sk), &wait);
1934 break;
1935 }
1936 release_sock(sk);
1937 timeout = schedule_timeout(timeout);
1938 lock_sock(sk);
1939
1940 if (signal_pending(current)) {
1941 err = sock_intr_errno(timeout);
1942 finish_wait(sk_sleep(sk), &wait);
1943 break;
1944 } else if (timeout == 0) {
1945 err = -EAGAIN;
1946 finish_wait(sk_sleep(sk), &wait);
1947 break;
1948 }
1949 } else {
1950 ssize_t read;
1951
1952 finish_wait(sk_sleep(sk), &wait);
1953
1954 if (ready < 0) {
1955 /* Invalid queue pair content. XXX This should
1956 * be changed to a connection reset in a later
1957 * change.
1958 */
1959
1960 err = -ENOMEM;
1961 goto out;
1962 }
1963
1964 err = transport->notify_recv_pre_dequeue(
1965 vsk, target, &recv_data);
1966 if (err < 0)
1967 break;
1968
1969 read = transport->stream_dequeue(
1970 vsk, msg,
1971 len - copied, flags);
1972 if (read < 0) {
1973 err = -ENOMEM;
1974 break;
1975 }
1976
1977 copied += read;
1978
1979 err = transport->notify_recv_post_dequeue(
1980 vsk, target, read,
1981 !(flags & MSG_PEEK), &recv_data);
1982 if (err < 0)
1983 goto out;
1984
1985 if (read >= target || flags & MSG_PEEK)
1986 break;
1987
1988 target -= read;
1989 }
1990 }
1991
1992 if (sk->sk_err)
1993 err = -sk->sk_err;
1994 else if (sk->sk_shutdown & RCV_SHUTDOWN)
1995 err = 0;
1996
1997 if (copied > 0)
1998 err = copied;
1999
2000 out:
2001 release_sock(sk);
2002 return err;
2003 }
2004
2005 static const struct proto_ops vsock_stream_ops = {
2006 .family = PF_VSOCK,
2007 .owner = THIS_MODULE,
2008 .release = vsock_release,
2009 .bind = vsock_bind,
2010 .connect = vsock_stream_connect,
2011 .socketpair = sock_no_socketpair,
2012 .accept = vsock_accept,
2013 .getname = vsock_getname,
2014 .poll = vsock_poll,
2015 .ioctl = sock_no_ioctl,
2016 .listen = vsock_listen,
2017 .shutdown = vsock_shutdown,
2018 .setsockopt = vsock_stream_setsockopt,
2019 .getsockopt = vsock_stream_getsockopt,
2020 .sendmsg = vsock_stream_sendmsg,
2021 .recvmsg = vsock_stream_recvmsg,
2022 .mmap = sock_no_mmap,
2023 .sendpage = sock_no_sendpage,
2024 };
2025
vsock_create(struct net * net,struct socket * sock,int protocol,int kern)2026 static int vsock_create(struct net *net, struct socket *sock,
2027 int protocol, int kern)
2028 {
2029 struct vsock_sock *vsk;
2030 struct sock *sk;
2031 int ret;
2032
2033 if (!sock)
2034 return -EINVAL;
2035
2036 if (protocol && protocol != PF_VSOCK)
2037 return -EPROTONOSUPPORT;
2038
2039 switch (sock->type) {
2040 case SOCK_DGRAM:
2041 sock->ops = &vsock_dgram_ops;
2042 break;
2043 case SOCK_STREAM:
2044 sock->ops = &vsock_stream_ops;
2045 break;
2046 default:
2047 return -ESOCKTNOSUPPORT;
2048 }
2049
2050 sock->state = SS_UNCONNECTED;
2051
2052 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern);
2053 if (!sk)
2054 return -ENOMEM;
2055
2056 vsk = vsock_sk(sk);
2057
2058 if (sock->type == SOCK_DGRAM) {
2059 ret = vsock_assign_transport(vsk, NULL);
2060 if (ret < 0) {
2061 sock_put(sk);
2062 return ret;
2063 }
2064 }
2065
2066 vsock_insert_unbound(vsk);
2067
2068 return 0;
2069 }
2070
2071 static const struct net_proto_family vsock_family_ops = {
2072 .family = AF_VSOCK,
2073 .create = vsock_create,
2074 .owner = THIS_MODULE,
2075 };
2076
vsock_dev_do_ioctl(struct file * filp,unsigned int cmd,void __user * ptr)2077 static long vsock_dev_do_ioctl(struct file *filp,
2078 unsigned int cmd, void __user *ptr)
2079 {
2080 u32 __user *p = ptr;
2081 u32 cid = VMADDR_CID_ANY;
2082 int retval = 0;
2083
2084 switch (cmd) {
2085 case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
2086 /* To be compatible with the VMCI behavior, we prioritize the
2087 * guest CID instead of well-know host CID (VMADDR_CID_HOST).
2088 */
2089 if (transport_g2h)
2090 cid = transport_g2h->get_local_cid();
2091 else if (transport_h2g)
2092 cid = transport_h2g->get_local_cid();
2093
2094 if (put_user(cid, p) != 0)
2095 retval = -EFAULT;
2096 break;
2097
2098 default:
2099 retval = -ENOIOCTLCMD;
2100 }
2101
2102 return retval;
2103 }
2104
vsock_dev_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)2105 static long vsock_dev_ioctl(struct file *filp,
2106 unsigned int cmd, unsigned long arg)
2107 {
2108 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
2109 }
2110
2111 #ifdef CONFIG_COMPAT
vsock_dev_compat_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)2112 static long vsock_dev_compat_ioctl(struct file *filp,
2113 unsigned int cmd, unsigned long arg)
2114 {
2115 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
2116 }
2117 #endif
2118
2119 static const struct file_operations vsock_device_ops = {
2120 .owner = THIS_MODULE,
2121 .unlocked_ioctl = vsock_dev_ioctl,
2122 #ifdef CONFIG_COMPAT
2123 .compat_ioctl = vsock_dev_compat_ioctl,
2124 #endif
2125 .open = nonseekable_open,
2126 };
2127
2128 static struct miscdevice vsock_device = {
2129 .name = "vsock",
2130 .fops = &vsock_device_ops,
2131 };
2132
vsock_init(void)2133 static int __init vsock_init(void)
2134 {
2135 int err = 0;
2136
2137 vsock_init_tables();
2138
2139 vsock_proto.owner = THIS_MODULE;
2140 vsock_device.minor = MISC_DYNAMIC_MINOR;
2141 err = misc_register(&vsock_device);
2142 if (err) {
2143 pr_err("Failed to register misc device\n");
2144 goto err_reset_transport;
2145 }
2146
2147 err = proto_register(&vsock_proto, 1); /* we want our slab */
2148 if (err) {
2149 pr_err("Cannot register vsock protocol\n");
2150 goto err_deregister_misc;
2151 }
2152
2153 err = sock_register(&vsock_family_ops);
2154 if (err) {
2155 pr_err("could not register af_vsock (%d) address family: %d\n",
2156 AF_VSOCK, err);
2157 goto err_unregister_proto;
2158 }
2159
2160 return 0;
2161
2162 err_unregister_proto:
2163 proto_unregister(&vsock_proto);
2164 err_deregister_misc:
2165 misc_deregister(&vsock_device);
2166 err_reset_transport:
2167 return err;
2168 }
2169
vsock_exit(void)2170 static void __exit vsock_exit(void)
2171 {
2172 misc_deregister(&vsock_device);
2173 sock_unregister(AF_VSOCK);
2174 proto_unregister(&vsock_proto);
2175 }
2176
vsock_core_get_transport(struct vsock_sock * vsk)2177 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk)
2178 {
2179 return vsk->transport;
2180 }
2181 EXPORT_SYMBOL_GPL(vsock_core_get_transport);
2182
vsock_core_register(const struct vsock_transport * t,int features)2183 int vsock_core_register(const struct vsock_transport *t, int features)
2184 {
2185 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local;
2186 int err = mutex_lock_interruptible(&vsock_register_mutex);
2187
2188 if (err)
2189 return err;
2190
2191 t_h2g = transport_h2g;
2192 t_g2h = transport_g2h;
2193 t_dgram = transport_dgram;
2194 t_local = transport_local;
2195
2196 if (features & VSOCK_TRANSPORT_F_H2G) {
2197 if (t_h2g) {
2198 err = -EBUSY;
2199 goto err_busy;
2200 }
2201 t_h2g = t;
2202 }
2203
2204 if (features & VSOCK_TRANSPORT_F_G2H) {
2205 if (t_g2h) {
2206 err = -EBUSY;
2207 goto err_busy;
2208 }
2209 t_g2h = t;
2210 }
2211
2212 if (features & VSOCK_TRANSPORT_F_DGRAM) {
2213 if (t_dgram) {
2214 err = -EBUSY;
2215 goto err_busy;
2216 }
2217 t_dgram = t;
2218 }
2219
2220 if (features & VSOCK_TRANSPORT_F_LOCAL) {
2221 if (t_local) {
2222 err = -EBUSY;
2223 goto err_busy;
2224 }
2225 t_local = t;
2226 }
2227
2228 transport_h2g = t_h2g;
2229 transport_g2h = t_g2h;
2230 transport_dgram = t_dgram;
2231 transport_local = t_local;
2232
2233 err_busy:
2234 mutex_unlock(&vsock_register_mutex);
2235 return err;
2236 }
2237 EXPORT_SYMBOL_GPL(vsock_core_register);
2238
vsock_core_unregister(const struct vsock_transport * t)2239 void vsock_core_unregister(const struct vsock_transport *t)
2240 {
2241 mutex_lock(&vsock_register_mutex);
2242
2243 if (transport_h2g == t)
2244 transport_h2g = NULL;
2245
2246 if (transport_g2h == t)
2247 transport_g2h = NULL;
2248
2249 if (transport_dgram == t)
2250 transport_dgram = NULL;
2251
2252 if (transport_local == t)
2253 transport_local = NULL;
2254
2255 mutex_unlock(&vsock_register_mutex);
2256 }
2257 EXPORT_SYMBOL_GPL(vsock_core_unregister);
2258
2259 module_init(vsock_init);
2260 module_exit(vsock_exit);
2261
2262 MODULE_AUTHOR("VMware, Inc.");
2263 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2264 MODULE_VERSION("1.0.2.0-k");
2265 MODULE_LICENSE("GPL v2");
2266