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(struct vsock_transport * transport,void (* fn)(struct sock * sk))336 void vsock_for_each_connected_socket(struct vsock_transport *transport,
337 void (*fn)(struct sock *sk))
338 {
339 int i;
340
341 spin_lock_bh(&vsock_table_lock);
342
343 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) {
344 struct vsock_sock *vsk;
345 list_for_each_entry(vsk, &vsock_connected_table[i],
346 connected_table) {
347 if (vsk->transport != transport)
348 continue;
349
350 fn(sk_vsock(vsk));
351 }
352 }
353
354 spin_unlock_bh(&vsock_table_lock);
355 }
356 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket);
357
vsock_add_pending(struct sock * listener,struct sock * pending)358 void vsock_add_pending(struct sock *listener, struct sock *pending)
359 {
360 struct vsock_sock *vlistener;
361 struct vsock_sock *vpending;
362
363 vlistener = vsock_sk(listener);
364 vpending = vsock_sk(pending);
365
366 sock_hold(pending);
367 sock_hold(listener);
368 list_add_tail(&vpending->pending_links, &vlistener->pending_links);
369 }
370 EXPORT_SYMBOL_GPL(vsock_add_pending);
371
vsock_remove_pending(struct sock * listener,struct sock * pending)372 void vsock_remove_pending(struct sock *listener, struct sock *pending)
373 {
374 struct vsock_sock *vpending = vsock_sk(pending);
375
376 list_del_init(&vpending->pending_links);
377 sock_put(listener);
378 sock_put(pending);
379 }
380 EXPORT_SYMBOL_GPL(vsock_remove_pending);
381
vsock_enqueue_accept(struct sock * listener,struct sock * connected)382 void vsock_enqueue_accept(struct sock *listener, struct sock *connected)
383 {
384 struct vsock_sock *vlistener;
385 struct vsock_sock *vconnected;
386
387 vlistener = vsock_sk(listener);
388 vconnected = vsock_sk(connected);
389
390 sock_hold(connected);
391 sock_hold(listener);
392 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue);
393 }
394 EXPORT_SYMBOL_GPL(vsock_enqueue_accept);
395
vsock_use_local_transport(unsigned int remote_cid)396 static bool vsock_use_local_transport(unsigned int remote_cid)
397 {
398 if (!transport_local)
399 return false;
400
401 if (remote_cid == VMADDR_CID_LOCAL)
402 return true;
403
404 if (transport_g2h) {
405 return remote_cid == transport_g2h->get_local_cid();
406 } else {
407 return remote_cid == VMADDR_CID_HOST;
408 }
409 }
410
vsock_deassign_transport(struct vsock_sock * vsk)411 static void vsock_deassign_transport(struct vsock_sock *vsk)
412 {
413 if (!vsk->transport)
414 return;
415
416 vsk->transport->destruct(vsk);
417 module_put(vsk->transport->module);
418 vsk->transport = NULL;
419 }
420
421 /* Assign a transport to a socket and call the .init transport callback.
422 *
423 * Note: for stream socket this must be called when vsk->remote_addr is set
424 * (e.g. during the connect() or when a connection request on a listener
425 * socket is received).
426 * The vsk->remote_addr is used to decide which transport to use:
427 * - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if
428 * g2h is not loaded, will use local transport;
429 * - remote CID <= VMADDR_CID_HOST will use guest->host transport;
430 * - remote CID > VMADDR_CID_HOST will use host->guest transport;
431 */
vsock_assign_transport(struct vsock_sock * vsk,struct vsock_sock * psk)432 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
433 {
434 const struct vsock_transport *new_transport;
435 struct sock *sk = sk_vsock(vsk);
436 unsigned int remote_cid = vsk->remote_addr.svm_cid;
437 int ret;
438
439 switch (sk->sk_type) {
440 case SOCK_DGRAM:
441 new_transport = transport_dgram;
442 break;
443 case SOCK_STREAM:
444 if (vsock_use_local_transport(remote_cid))
445 new_transport = transport_local;
446 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g)
447 new_transport = transport_g2h;
448 else
449 new_transport = transport_h2g;
450 break;
451 default:
452 return -ESOCKTNOSUPPORT;
453 }
454
455 if (vsk->transport) {
456 if (vsk->transport == new_transport)
457 return 0;
458
459 /* transport->release() must be called with sock lock acquired.
460 * This path can only be taken during vsock_stream_connect(),
461 * where we have already held the sock lock.
462 * In the other cases, this function is called on a new socket
463 * which is not assigned to any transport.
464 */
465 vsk->transport->release(vsk);
466 vsock_deassign_transport(vsk);
467 }
468
469 /* We increase the module refcnt to prevent the transport unloading
470 * while there are open sockets assigned to it.
471 */
472 if (!new_transport || !try_module_get(new_transport->module))
473 return -ENODEV;
474
475 ret = new_transport->init(vsk, psk);
476 if (ret) {
477 module_put(new_transport->module);
478 return ret;
479 }
480
481 vsk->transport = new_transport;
482
483 return 0;
484 }
485 EXPORT_SYMBOL_GPL(vsock_assign_transport);
486
vsock_find_cid(unsigned int cid)487 bool vsock_find_cid(unsigned int cid)
488 {
489 if (transport_g2h && cid == transport_g2h->get_local_cid())
490 return true;
491
492 if (transport_h2g && cid == VMADDR_CID_HOST)
493 return true;
494
495 if (transport_local && cid == VMADDR_CID_LOCAL)
496 return true;
497
498 return false;
499 }
500 EXPORT_SYMBOL_GPL(vsock_find_cid);
501
vsock_dequeue_accept(struct sock * listener)502 static struct sock *vsock_dequeue_accept(struct sock *listener)
503 {
504 struct vsock_sock *vlistener;
505 struct vsock_sock *vconnected;
506
507 vlistener = vsock_sk(listener);
508
509 if (list_empty(&vlistener->accept_queue))
510 return NULL;
511
512 vconnected = list_entry(vlistener->accept_queue.next,
513 struct vsock_sock, accept_queue);
514
515 list_del_init(&vconnected->accept_queue);
516 sock_put(listener);
517 /* The caller will need a reference on the connected socket so we let
518 * it call sock_put().
519 */
520
521 return sk_vsock(vconnected);
522 }
523
vsock_is_accept_queue_empty(struct sock * sk)524 static bool vsock_is_accept_queue_empty(struct sock *sk)
525 {
526 struct vsock_sock *vsk = vsock_sk(sk);
527 return list_empty(&vsk->accept_queue);
528 }
529
vsock_is_pending(struct sock * sk)530 static bool vsock_is_pending(struct sock *sk)
531 {
532 struct vsock_sock *vsk = vsock_sk(sk);
533 return !list_empty(&vsk->pending_links);
534 }
535
vsock_send_shutdown(struct sock * sk,int mode)536 static int vsock_send_shutdown(struct sock *sk, int mode)
537 {
538 struct vsock_sock *vsk = vsock_sk(sk);
539
540 if (!vsk->transport)
541 return -ENODEV;
542
543 return vsk->transport->shutdown(vsk, mode);
544 }
545
vsock_pending_work(struct work_struct * work)546 static void vsock_pending_work(struct work_struct *work)
547 {
548 struct sock *sk;
549 struct sock *listener;
550 struct vsock_sock *vsk;
551 bool cleanup;
552
553 vsk = container_of(work, struct vsock_sock, pending_work.work);
554 sk = sk_vsock(vsk);
555 listener = vsk->listener;
556 cleanup = true;
557
558 lock_sock(listener);
559 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
560
561 if (vsock_is_pending(sk)) {
562 vsock_remove_pending(listener, sk);
563
564 sk_acceptq_removed(listener);
565 } else if (!vsk->rejected) {
566 /* We are not on the pending list and accept() did not reject
567 * us, so we must have been accepted by our user process. We
568 * just need to drop our references to the sockets and be on
569 * our way.
570 */
571 cleanup = false;
572 goto out;
573 }
574
575 /* We need to remove ourself from the global connected sockets list so
576 * incoming packets can't find this socket, and to reduce the reference
577 * count.
578 */
579 vsock_remove_connected(vsk);
580
581 sk->sk_state = TCP_CLOSE;
582
583 out:
584 release_sock(sk);
585 release_sock(listener);
586 if (cleanup)
587 sock_put(sk);
588
589 sock_put(sk);
590 sock_put(listener);
591 }
592
593 /**** SOCKET OPERATIONS ****/
594
__vsock_bind_stream(struct vsock_sock * vsk,struct sockaddr_vm * addr)595 static int __vsock_bind_stream(struct vsock_sock *vsk,
596 struct sockaddr_vm *addr)
597 {
598 static u32 port;
599 struct sockaddr_vm new_addr;
600
601 if (!port)
602 port = LAST_RESERVED_PORT + 1 +
603 prandom_u32_max(U32_MAX - LAST_RESERVED_PORT);
604
605 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
606
607 if (addr->svm_port == VMADDR_PORT_ANY) {
608 bool found = false;
609 unsigned int i;
610
611 for (i = 0; i < MAX_PORT_RETRIES; i++) {
612 if (port <= LAST_RESERVED_PORT)
613 port = LAST_RESERVED_PORT + 1;
614
615 new_addr.svm_port = port++;
616
617 if (!__vsock_find_bound_socket(&new_addr)) {
618 found = true;
619 break;
620 }
621 }
622
623 if (!found)
624 return -EADDRNOTAVAIL;
625 } else {
626 /* If port is in reserved range, ensure caller
627 * has necessary privileges.
628 */
629 if (addr->svm_port <= LAST_RESERVED_PORT &&
630 !capable(CAP_NET_BIND_SERVICE)) {
631 return -EACCES;
632 }
633
634 if (__vsock_find_bound_socket(&new_addr))
635 return -EADDRINUSE;
636 }
637
638 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
639
640 /* Remove stream sockets from the unbound list and add them to the hash
641 * table for easy lookup by its address. The unbound list is simply an
642 * extra entry at the end of the hash table, a trick used by AF_UNIX.
643 */
644 __vsock_remove_bound(vsk);
645 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
646
647 return 0;
648 }
649
__vsock_bind_dgram(struct vsock_sock * vsk,struct sockaddr_vm * addr)650 static int __vsock_bind_dgram(struct vsock_sock *vsk,
651 struct sockaddr_vm *addr)
652 {
653 return vsk->transport->dgram_bind(vsk, addr);
654 }
655
__vsock_bind(struct sock * sk,struct sockaddr_vm * addr)656 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
657 {
658 struct vsock_sock *vsk = vsock_sk(sk);
659 int retval;
660
661 /* First ensure this socket isn't already bound. */
662 if (vsock_addr_bound(&vsk->local_addr))
663 return -EINVAL;
664
665 /* Now bind to the provided address or select appropriate values if
666 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that
667 * like AF_INET prevents binding to a non-local IP address (in most
668 * cases), we only allow binding to a local CID.
669 */
670 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid))
671 return -EADDRNOTAVAIL;
672
673 switch (sk->sk_socket->type) {
674 case SOCK_STREAM:
675 spin_lock_bh(&vsock_table_lock);
676 retval = __vsock_bind_stream(vsk, addr);
677 spin_unlock_bh(&vsock_table_lock);
678 break;
679
680 case SOCK_DGRAM:
681 retval = __vsock_bind_dgram(vsk, addr);
682 break;
683
684 default:
685 retval = -EINVAL;
686 break;
687 }
688
689 return retval;
690 }
691
692 static void vsock_connect_timeout(struct work_struct *work);
693
__vsock_create(struct net * net,struct socket * sock,struct sock * parent,gfp_t priority,unsigned short type,int kern)694 static struct sock *__vsock_create(struct net *net,
695 struct socket *sock,
696 struct sock *parent,
697 gfp_t priority,
698 unsigned short type,
699 int kern)
700 {
701 struct sock *sk;
702 struct vsock_sock *psk;
703 struct vsock_sock *vsk;
704
705 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern);
706 if (!sk)
707 return NULL;
708
709 sock_init_data(sock, sk);
710
711 /* sk->sk_type is normally set in sock_init_data, but only if sock is
712 * non-NULL. We make sure that our sockets always have a type by
713 * setting it here if needed.
714 */
715 if (!sock)
716 sk->sk_type = type;
717
718 vsk = vsock_sk(sk);
719 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
720 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
721
722 sk->sk_destruct = vsock_sk_destruct;
723 sk->sk_backlog_rcv = vsock_queue_rcv_skb;
724 sock_reset_flag(sk, SOCK_DONE);
725
726 INIT_LIST_HEAD(&vsk->bound_table);
727 INIT_LIST_HEAD(&vsk->connected_table);
728 vsk->listener = NULL;
729 INIT_LIST_HEAD(&vsk->pending_links);
730 INIT_LIST_HEAD(&vsk->accept_queue);
731 vsk->rejected = false;
732 vsk->sent_request = false;
733 vsk->ignore_connecting_rst = false;
734 vsk->peer_shutdown = 0;
735 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout);
736 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work);
737
738 psk = parent ? vsock_sk(parent) : NULL;
739 if (parent) {
740 vsk->trusted = psk->trusted;
741 vsk->owner = get_cred(psk->owner);
742 vsk->connect_timeout = psk->connect_timeout;
743 vsk->buffer_size = psk->buffer_size;
744 vsk->buffer_min_size = psk->buffer_min_size;
745 vsk->buffer_max_size = psk->buffer_max_size;
746 security_sk_clone(parent, sk);
747 } else {
748 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN);
749 vsk->owner = get_current_cred();
750 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
751 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE;
752 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE;
753 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE;
754 }
755
756 return sk;
757 }
758
__vsock_release(struct sock * sk,int level)759 static void __vsock_release(struct sock *sk, int level)
760 {
761 if (sk) {
762 struct sock *pending;
763 struct vsock_sock *vsk;
764
765 vsk = vsock_sk(sk);
766 pending = NULL; /* Compiler warning. */
767
768 /* When "level" is SINGLE_DEPTH_NESTING, use the nested
769 * version to avoid the warning "possible recursive locking
770 * detected". When "level" is 0, lock_sock_nested(sk, level)
771 * is the same as lock_sock(sk).
772 */
773 lock_sock_nested(sk, level);
774
775 if (vsk->transport)
776 vsk->transport->release(vsk);
777 else if (sk->sk_type == SOCK_STREAM)
778 vsock_remove_sock(vsk);
779
780 sock_orphan(sk);
781 sk->sk_shutdown = SHUTDOWN_MASK;
782
783 skb_queue_purge(&sk->sk_receive_queue);
784
785 /* Clean up any sockets that never were accepted. */
786 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
787 __vsock_release(pending, SINGLE_DEPTH_NESTING);
788 sock_put(pending);
789 }
790
791 release_sock(sk);
792 sock_put(sk);
793 }
794 }
795
vsock_sk_destruct(struct sock * sk)796 static void vsock_sk_destruct(struct sock *sk)
797 {
798 struct vsock_sock *vsk = vsock_sk(sk);
799
800 vsock_deassign_transport(vsk);
801
802 /* When clearing these addresses, there's no need to set the family and
803 * possibly register the address family with the kernel.
804 */
805 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
806 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
807
808 put_cred(vsk->owner);
809 }
810
vsock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)811 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
812 {
813 int err;
814
815 err = sock_queue_rcv_skb(sk, skb);
816 if (err)
817 kfree_skb(skb);
818
819 return err;
820 }
821
vsock_create_connected(struct sock * parent)822 struct sock *vsock_create_connected(struct sock *parent)
823 {
824 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL,
825 parent->sk_type, 0);
826 }
827 EXPORT_SYMBOL_GPL(vsock_create_connected);
828
vsock_stream_has_data(struct vsock_sock * vsk)829 s64 vsock_stream_has_data(struct vsock_sock *vsk)
830 {
831 return vsk->transport->stream_has_data(vsk);
832 }
833 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
834
vsock_stream_has_space(struct vsock_sock * vsk)835 s64 vsock_stream_has_space(struct vsock_sock *vsk)
836 {
837 return vsk->transport->stream_has_space(vsk);
838 }
839 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
840
vsock_release(struct socket * sock)841 static int vsock_release(struct socket *sock)
842 {
843 __vsock_release(sock->sk, 0);
844 sock->sk = NULL;
845 sock->state = SS_FREE;
846
847 return 0;
848 }
849
850 static int
vsock_bind(struct socket * sock,struct sockaddr * addr,int addr_len)851 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
852 {
853 int err;
854 struct sock *sk;
855 struct sockaddr_vm *vm_addr;
856
857 sk = sock->sk;
858
859 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
860 return -EINVAL;
861
862 lock_sock(sk);
863 err = __vsock_bind(sk, vm_addr);
864 release_sock(sk);
865
866 return err;
867 }
868
vsock_getname(struct socket * sock,struct sockaddr * addr,int peer)869 static int vsock_getname(struct socket *sock,
870 struct sockaddr *addr, int peer)
871 {
872 int err;
873 struct sock *sk;
874 struct vsock_sock *vsk;
875 struct sockaddr_vm *vm_addr;
876
877 sk = sock->sk;
878 vsk = vsock_sk(sk);
879 err = 0;
880
881 lock_sock(sk);
882
883 if (peer) {
884 if (sock->state != SS_CONNECTED) {
885 err = -ENOTCONN;
886 goto out;
887 }
888 vm_addr = &vsk->remote_addr;
889 } else {
890 vm_addr = &vsk->local_addr;
891 }
892
893 if (!vm_addr) {
894 err = -EINVAL;
895 goto out;
896 }
897
898 /* sys_getsockname() and sys_getpeername() pass us a
899 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately
900 * that macro is defined in socket.c instead of .h, so we hardcode its
901 * value here.
902 */
903 BUILD_BUG_ON(sizeof(*vm_addr) > 128);
904 memcpy(addr, vm_addr, sizeof(*vm_addr));
905 err = sizeof(*vm_addr);
906
907 out:
908 release_sock(sk);
909 return err;
910 }
911
vsock_shutdown(struct socket * sock,int mode)912 static int vsock_shutdown(struct socket *sock, int mode)
913 {
914 int err;
915 struct sock *sk;
916
917 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
918 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
919 * here like the other address families do. Note also that the
920 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
921 * which is what we want.
922 */
923 mode++;
924
925 if ((mode & ~SHUTDOWN_MASK) || !mode)
926 return -EINVAL;
927
928 /* If this is a STREAM socket and it is not connected then bail out
929 * immediately. If it is a DGRAM socket then we must first kick the
930 * socket so that it wakes up from any sleeping calls, for example
931 * recv(), and then afterwards return the error.
932 */
933
934 sk = sock->sk;
935
936 lock_sock(sk);
937 if (sock->state == SS_UNCONNECTED) {
938 err = -ENOTCONN;
939 if (sk->sk_type == SOCK_STREAM)
940 goto out;
941 } else {
942 sock->state = SS_DISCONNECTING;
943 err = 0;
944 }
945
946 /* Receive and send shutdowns are treated alike. */
947 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
948 if (mode) {
949 sk->sk_shutdown |= mode;
950 sk->sk_state_change(sk);
951
952 if (sk->sk_type == SOCK_STREAM) {
953 sock_reset_flag(sk, SOCK_DONE);
954 vsock_send_shutdown(sk, mode);
955 }
956 }
957
958 out:
959 release_sock(sk);
960 return err;
961 }
962
vsock_poll(struct file * file,struct socket * sock,poll_table * wait)963 static __poll_t vsock_poll(struct file *file, struct socket *sock,
964 poll_table *wait)
965 {
966 struct sock *sk;
967 __poll_t mask;
968 struct vsock_sock *vsk;
969
970 sk = sock->sk;
971 vsk = vsock_sk(sk);
972
973 poll_wait(file, sk_sleep(sk), wait);
974 mask = 0;
975
976 if (sk->sk_err)
977 /* Signify that there has been an error on this socket. */
978 mask |= EPOLLERR;
979
980 /* INET sockets treat local write shutdown and peer write shutdown as a
981 * case of EPOLLHUP set.
982 */
983 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
984 ((sk->sk_shutdown & SEND_SHUTDOWN) &&
985 (vsk->peer_shutdown & SEND_SHUTDOWN))) {
986 mask |= EPOLLHUP;
987 }
988
989 if (sk->sk_shutdown & RCV_SHUTDOWN ||
990 vsk->peer_shutdown & SEND_SHUTDOWN) {
991 mask |= EPOLLRDHUP;
992 }
993
994 if (sock->type == SOCK_DGRAM) {
995 /* For datagram sockets we can read if there is something in
996 * the queue and write as long as the socket isn't shutdown for
997 * sending.
998 */
999 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1000 (sk->sk_shutdown & RCV_SHUTDOWN)) {
1001 mask |= EPOLLIN | EPOLLRDNORM;
1002 }
1003
1004 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1005 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1006
1007 } else if (sock->type == SOCK_STREAM) {
1008 const struct vsock_transport *transport;
1009
1010 lock_sock(sk);
1011
1012 transport = vsk->transport;
1013
1014 /* Listening sockets that have connections in their accept
1015 * queue can be read.
1016 */
1017 if (sk->sk_state == TCP_LISTEN
1018 && !vsock_is_accept_queue_empty(sk))
1019 mask |= EPOLLIN | EPOLLRDNORM;
1020
1021 /* If there is something in the queue then we can read. */
1022 if (transport && transport->stream_is_active(vsk) &&
1023 !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1024 bool data_ready_now = false;
1025 int ret = transport->notify_poll_in(
1026 vsk, 1, &data_ready_now);
1027 if (ret < 0) {
1028 mask |= EPOLLERR;
1029 } else {
1030 if (data_ready_now)
1031 mask |= EPOLLIN | EPOLLRDNORM;
1032
1033 }
1034 }
1035
1036 /* Sockets whose connections have been closed, reset, or
1037 * terminated should also be considered read, and we check the
1038 * shutdown flag for that.
1039 */
1040 if (sk->sk_shutdown & RCV_SHUTDOWN ||
1041 vsk->peer_shutdown & SEND_SHUTDOWN) {
1042 mask |= EPOLLIN | EPOLLRDNORM;
1043 }
1044
1045 /* Connected sockets that can produce data can be written. */
1046 if (transport && sk->sk_state == TCP_ESTABLISHED) {
1047 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1048 bool space_avail_now = false;
1049 int ret = transport->notify_poll_out(
1050 vsk, 1, &space_avail_now);
1051 if (ret < 0) {
1052 mask |= EPOLLERR;
1053 } else {
1054 if (space_avail_now)
1055 /* Remove EPOLLWRBAND since INET
1056 * sockets are not setting it.
1057 */
1058 mask |= EPOLLOUT | EPOLLWRNORM;
1059
1060 }
1061 }
1062 }
1063
1064 /* Simulate INET socket poll behaviors, which sets
1065 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read,
1066 * but local send is not shutdown.
1067 */
1068 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) {
1069 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1070 mask |= EPOLLOUT | EPOLLWRNORM;
1071
1072 }
1073
1074 release_sock(sk);
1075 }
1076
1077 return mask;
1078 }
1079
vsock_dgram_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)1080 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
1081 size_t len)
1082 {
1083 int err;
1084 struct sock *sk;
1085 struct vsock_sock *vsk;
1086 struct sockaddr_vm *remote_addr;
1087 const struct vsock_transport *transport;
1088
1089 if (msg->msg_flags & MSG_OOB)
1090 return -EOPNOTSUPP;
1091
1092 /* For now, MSG_DONTWAIT is always assumed... */
1093 err = 0;
1094 sk = sock->sk;
1095 vsk = vsock_sk(sk);
1096
1097 lock_sock(sk);
1098
1099 transport = vsk->transport;
1100
1101 err = vsock_auto_bind(vsk);
1102 if (err)
1103 goto out;
1104
1105
1106 /* If the provided message contains an address, use that. Otherwise
1107 * fall back on the socket's remote handle (if it has been connected).
1108 */
1109 if (msg->msg_name &&
1110 vsock_addr_cast(msg->msg_name, msg->msg_namelen,
1111 &remote_addr) == 0) {
1112 /* Ensure this address is of the right type and is a valid
1113 * destination.
1114 */
1115
1116 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1117 remote_addr->svm_cid = transport->get_local_cid();
1118
1119 if (!vsock_addr_bound(remote_addr)) {
1120 err = -EINVAL;
1121 goto out;
1122 }
1123 } else if (sock->state == SS_CONNECTED) {
1124 remote_addr = &vsk->remote_addr;
1125
1126 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1127 remote_addr->svm_cid = transport->get_local_cid();
1128
1129 /* XXX Should connect() or this function ensure remote_addr is
1130 * bound?
1131 */
1132 if (!vsock_addr_bound(&vsk->remote_addr)) {
1133 err = -EINVAL;
1134 goto out;
1135 }
1136 } else {
1137 err = -EINVAL;
1138 goto out;
1139 }
1140
1141 if (!transport->dgram_allow(remote_addr->svm_cid,
1142 remote_addr->svm_port)) {
1143 err = -EINVAL;
1144 goto out;
1145 }
1146
1147 err = transport->dgram_enqueue(vsk, remote_addr, msg, len);
1148
1149 out:
1150 release_sock(sk);
1151 return err;
1152 }
1153
vsock_dgram_connect(struct socket * sock,struct sockaddr * addr,int addr_len,int flags)1154 static int vsock_dgram_connect(struct socket *sock,
1155 struct sockaddr *addr, int addr_len, int flags)
1156 {
1157 int err;
1158 struct sock *sk;
1159 struct vsock_sock *vsk;
1160 struct sockaddr_vm *remote_addr;
1161
1162 sk = sock->sk;
1163 vsk = vsock_sk(sk);
1164
1165 err = vsock_addr_cast(addr, addr_len, &remote_addr);
1166 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1167 lock_sock(sk);
1168 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1169 VMADDR_PORT_ANY);
1170 sock->state = SS_UNCONNECTED;
1171 release_sock(sk);
1172 return 0;
1173 } else if (err != 0)
1174 return -EINVAL;
1175
1176 lock_sock(sk);
1177
1178 err = vsock_auto_bind(vsk);
1179 if (err)
1180 goto out;
1181
1182 if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
1183 remote_addr->svm_port)) {
1184 err = -EINVAL;
1185 goto out;
1186 }
1187
1188 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1189 sock->state = SS_CONNECTED;
1190
1191 out:
1192 release_sock(sk);
1193 return err;
1194 }
1195
vsock_dgram_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)1196 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
1197 size_t len, int flags)
1198 {
1199 struct vsock_sock *vsk = vsock_sk(sock->sk);
1200
1201 return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
1202 }
1203
1204 static const struct proto_ops vsock_dgram_ops = {
1205 .family = PF_VSOCK,
1206 .owner = THIS_MODULE,
1207 .release = vsock_release,
1208 .bind = vsock_bind,
1209 .connect = vsock_dgram_connect,
1210 .socketpair = sock_no_socketpair,
1211 .accept = sock_no_accept,
1212 .getname = vsock_getname,
1213 .poll = vsock_poll,
1214 .ioctl = sock_no_ioctl,
1215 .listen = sock_no_listen,
1216 .shutdown = vsock_shutdown,
1217 .sendmsg = vsock_dgram_sendmsg,
1218 .recvmsg = vsock_dgram_recvmsg,
1219 .mmap = sock_no_mmap,
1220 .sendpage = sock_no_sendpage,
1221 };
1222
vsock_transport_cancel_pkt(struct vsock_sock * vsk)1223 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
1224 {
1225 const struct vsock_transport *transport = vsk->transport;
1226
1227 if (!transport || !transport->cancel_pkt)
1228 return -EOPNOTSUPP;
1229
1230 return transport->cancel_pkt(vsk);
1231 }
1232
vsock_connect_timeout(struct work_struct * work)1233 static void vsock_connect_timeout(struct work_struct *work)
1234 {
1235 struct sock *sk;
1236 struct vsock_sock *vsk;
1237
1238 vsk = container_of(work, struct vsock_sock, connect_work.work);
1239 sk = sk_vsock(vsk);
1240
1241 lock_sock(sk);
1242 if (sk->sk_state == TCP_SYN_SENT &&
1243 (sk->sk_shutdown != SHUTDOWN_MASK)) {
1244 sk->sk_state = TCP_CLOSE;
1245 sk->sk_socket->state = SS_UNCONNECTED;
1246 sk->sk_err = ETIMEDOUT;
1247 sk->sk_error_report(sk);
1248 vsock_transport_cancel_pkt(vsk);
1249 }
1250 release_sock(sk);
1251
1252 sock_put(sk);
1253 }
1254
vsock_stream_connect(struct socket * sock,struct sockaddr * addr,int addr_len,int flags)1255 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1256 int addr_len, int flags)
1257 {
1258 int err;
1259 struct sock *sk;
1260 struct vsock_sock *vsk;
1261 const struct vsock_transport *transport;
1262 struct sockaddr_vm *remote_addr;
1263 long timeout;
1264 DEFINE_WAIT(wait);
1265
1266 err = 0;
1267 sk = sock->sk;
1268 vsk = vsock_sk(sk);
1269
1270 lock_sock(sk);
1271
1272 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1273 switch (sock->state) {
1274 case SS_CONNECTED:
1275 err = -EISCONN;
1276 goto out;
1277 case SS_DISCONNECTING:
1278 err = -EINVAL;
1279 goto out;
1280 case SS_CONNECTING:
1281 /* This continues on so we can move sock into the SS_CONNECTED
1282 * state once the connection has completed (at which point err
1283 * will be set to zero also). Otherwise, we will either wait
1284 * for the connection or return -EALREADY should this be a
1285 * non-blocking call.
1286 */
1287 err = -EALREADY;
1288 if (flags & O_NONBLOCK)
1289 goto out;
1290 break;
1291 default:
1292 if ((sk->sk_state == TCP_LISTEN) ||
1293 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1294 err = -EINVAL;
1295 goto out;
1296 }
1297
1298 /* Set the remote address that we are connecting to. */
1299 memcpy(&vsk->remote_addr, remote_addr,
1300 sizeof(vsk->remote_addr));
1301
1302 err = vsock_assign_transport(vsk, NULL);
1303 if (err)
1304 goto out;
1305
1306 transport = vsk->transport;
1307
1308 /* The hypervisor and well-known contexts do not have socket
1309 * endpoints.
1310 */
1311 if (!transport ||
1312 !transport->stream_allow(remote_addr->svm_cid,
1313 remote_addr->svm_port)) {
1314 err = -ENETUNREACH;
1315 goto out;
1316 }
1317
1318 err = vsock_auto_bind(vsk);
1319 if (err)
1320 goto out;
1321
1322 sk->sk_state = TCP_SYN_SENT;
1323
1324 err = transport->connect(vsk);
1325 if (err < 0)
1326 goto out;
1327
1328 /* Mark sock as connecting and set the error code to in
1329 * progress in case this is a non-blocking connect.
1330 */
1331 sock->state = SS_CONNECTING;
1332 err = -EINPROGRESS;
1333 }
1334
1335 /* The receive path will handle all communication until we are able to
1336 * enter the connected state. Here we wait for the connection to be
1337 * completed or a notification of an error.
1338 */
1339 timeout = vsk->connect_timeout;
1340 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1341
1342 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
1343 if (flags & O_NONBLOCK) {
1344 /* If we're not going to block, we schedule a timeout
1345 * function to generate a timeout on the connection
1346 * attempt, in case the peer doesn't respond in a
1347 * timely manner. We hold on to the socket until the
1348 * timeout fires.
1349 */
1350 sock_hold(sk);
1351
1352 /* If the timeout function is already scheduled,
1353 * reschedule it, then ungrab the socket refcount to
1354 * keep it balanced.
1355 */
1356 if (mod_delayed_work(system_wq, &vsk->connect_work,
1357 timeout))
1358 sock_put(sk);
1359
1360 /* Skip ahead to preserve error code set above. */
1361 goto out_wait;
1362 }
1363
1364 release_sock(sk);
1365 timeout = schedule_timeout(timeout);
1366 lock_sock(sk);
1367
1368 if (signal_pending(current)) {
1369 err = sock_intr_errno(timeout);
1370 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE;
1371 sock->state = SS_UNCONNECTED;
1372 vsock_transport_cancel_pkt(vsk);
1373 vsock_remove_connected(vsk);
1374 goto out_wait;
1375 } else if (timeout == 0) {
1376 err = -ETIMEDOUT;
1377 sk->sk_state = TCP_CLOSE;
1378 sock->state = SS_UNCONNECTED;
1379 vsock_transport_cancel_pkt(vsk);
1380 goto out_wait;
1381 }
1382
1383 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1384 }
1385
1386 if (sk->sk_err) {
1387 err = -sk->sk_err;
1388 sk->sk_state = TCP_CLOSE;
1389 sock->state = SS_UNCONNECTED;
1390 } else {
1391 err = 0;
1392 }
1393
1394 out_wait:
1395 finish_wait(sk_sleep(sk), &wait);
1396 out:
1397 release_sock(sk);
1398 return err;
1399 }
1400
vsock_accept(struct socket * sock,struct socket * newsock,int flags,bool kern)1401 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
1402 bool kern)
1403 {
1404 struct sock *listener;
1405 int err;
1406 struct sock *connected;
1407 struct vsock_sock *vconnected;
1408 long timeout;
1409 DEFINE_WAIT(wait);
1410
1411 err = 0;
1412 listener = sock->sk;
1413
1414 lock_sock(listener);
1415
1416 if (sock->type != SOCK_STREAM) {
1417 err = -EOPNOTSUPP;
1418 goto out;
1419 }
1420
1421 if (listener->sk_state != TCP_LISTEN) {
1422 err = -EINVAL;
1423 goto out;
1424 }
1425
1426 /* Wait for children sockets to appear; these are the new sockets
1427 * created upon connection establishment.
1428 */
1429 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK);
1430 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1431
1432 while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1433 listener->sk_err == 0) {
1434 release_sock(listener);
1435 timeout = schedule_timeout(timeout);
1436 finish_wait(sk_sleep(listener), &wait);
1437 lock_sock(listener);
1438
1439 if (signal_pending(current)) {
1440 err = sock_intr_errno(timeout);
1441 goto out;
1442 } else if (timeout == 0) {
1443 err = -EAGAIN;
1444 goto out;
1445 }
1446
1447 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1448 }
1449 finish_wait(sk_sleep(listener), &wait);
1450
1451 if (listener->sk_err)
1452 err = -listener->sk_err;
1453
1454 if (connected) {
1455 sk_acceptq_removed(listener);
1456
1457 lock_sock_nested(connected, SINGLE_DEPTH_NESTING);
1458 vconnected = vsock_sk(connected);
1459
1460 /* If the listener socket has received an error, then we should
1461 * reject this socket and return. Note that we simply mark the
1462 * socket rejected, drop our reference, and let the cleanup
1463 * function handle the cleanup; the fact that we found it in
1464 * the listener's accept queue guarantees that the cleanup
1465 * function hasn't run yet.
1466 */
1467 if (err) {
1468 vconnected->rejected = true;
1469 } else {
1470 newsock->state = SS_CONNECTED;
1471 sock_graft(connected, newsock);
1472 }
1473
1474 release_sock(connected);
1475 sock_put(connected);
1476 }
1477
1478 out:
1479 release_sock(listener);
1480 return err;
1481 }
1482
vsock_listen(struct socket * sock,int backlog)1483 static int vsock_listen(struct socket *sock, int backlog)
1484 {
1485 int err;
1486 struct sock *sk;
1487 struct vsock_sock *vsk;
1488
1489 sk = sock->sk;
1490
1491 lock_sock(sk);
1492
1493 if (sock->type != SOCK_STREAM) {
1494 err = -EOPNOTSUPP;
1495 goto out;
1496 }
1497
1498 if (sock->state != SS_UNCONNECTED) {
1499 err = -EINVAL;
1500 goto out;
1501 }
1502
1503 vsk = vsock_sk(sk);
1504
1505 if (!vsock_addr_bound(&vsk->local_addr)) {
1506 err = -EINVAL;
1507 goto out;
1508 }
1509
1510 sk->sk_max_ack_backlog = backlog;
1511 sk->sk_state = TCP_LISTEN;
1512
1513 err = 0;
1514
1515 out:
1516 release_sock(sk);
1517 return err;
1518 }
1519
vsock_update_buffer_size(struct vsock_sock * vsk,const struct vsock_transport * transport,u64 val)1520 static void vsock_update_buffer_size(struct vsock_sock *vsk,
1521 const struct vsock_transport *transport,
1522 u64 val)
1523 {
1524 if (val > vsk->buffer_max_size)
1525 val = vsk->buffer_max_size;
1526
1527 if (val < vsk->buffer_min_size)
1528 val = vsk->buffer_min_size;
1529
1530 if (val != vsk->buffer_size &&
1531 transport && transport->notify_buffer_size)
1532 transport->notify_buffer_size(vsk, &val);
1533
1534 vsk->buffer_size = val;
1535 }
1536
vsock_stream_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1537 static int vsock_stream_setsockopt(struct socket *sock,
1538 int level,
1539 int optname,
1540 sockptr_t optval,
1541 unsigned int optlen)
1542 {
1543 int err;
1544 struct sock *sk;
1545 struct vsock_sock *vsk;
1546 const struct vsock_transport *transport;
1547 u64 val;
1548
1549 if (level != AF_VSOCK)
1550 return -ENOPROTOOPT;
1551
1552 #define COPY_IN(_v) \
1553 do { \
1554 if (optlen < sizeof(_v)) { \
1555 err = -EINVAL; \
1556 goto exit; \
1557 } \
1558 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \
1559 err = -EFAULT; \
1560 goto exit; \
1561 } \
1562 } while (0)
1563
1564 err = 0;
1565 sk = sock->sk;
1566 vsk = vsock_sk(sk);
1567
1568 lock_sock(sk);
1569
1570 transport = vsk->transport;
1571
1572 switch (optname) {
1573 case SO_VM_SOCKETS_BUFFER_SIZE:
1574 COPY_IN(val);
1575 vsock_update_buffer_size(vsk, transport, val);
1576 break;
1577
1578 case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1579 COPY_IN(val);
1580 vsk->buffer_max_size = val;
1581 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1582 break;
1583
1584 case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1585 COPY_IN(val);
1586 vsk->buffer_min_size = val;
1587 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1588 break;
1589
1590 case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1591 struct __kernel_old_timeval tv;
1592 COPY_IN(tv);
1593 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1594 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1595 vsk->connect_timeout = tv.tv_sec * HZ +
1596 DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1597 if (vsk->connect_timeout == 0)
1598 vsk->connect_timeout =
1599 VSOCK_DEFAULT_CONNECT_TIMEOUT;
1600
1601 } else {
1602 err = -ERANGE;
1603 }
1604 break;
1605 }
1606
1607 default:
1608 err = -ENOPROTOOPT;
1609 break;
1610 }
1611
1612 #undef COPY_IN
1613
1614 exit:
1615 release_sock(sk);
1616 return err;
1617 }
1618
vsock_stream_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)1619 static int vsock_stream_getsockopt(struct socket *sock,
1620 int level, int optname,
1621 char __user *optval,
1622 int __user *optlen)
1623 {
1624 int err;
1625 int len;
1626 struct sock *sk;
1627 struct vsock_sock *vsk;
1628 u64 val;
1629
1630 if (level != AF_VSOCK)
1631 return -ENOPROTOOPT;
1632
1633 err = get_user(len, optlen);
1634 if (err != 0)
1635 return err;
1636
1637 #define COPY_OUT(_v) \
1638 do { \
1639 if (len < sizeof(_v)) \
1640 return -EINVAL; \
1641 \
1642 len = sizeof(_v); \
1643 if (copy_to_user(optval, &_v, len) != 0) \
1644 return -EFAULT; \
1645 \
1646 } while (0)
1647
1648 err = 0;
1649 sk = sock->sk;
1650 vsk = vsock_sk(sk);
1651
1652 switch (optname) {
1653 case SO_VM_SOCKETS_BUFFER_SIZE:
1654 val = vsk->buffer_size;
1655 COPY_OUT(val);
1656 break;
1657
1658 case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1659 val = vsk->buffer_max_size;
1660 COPY_OUT(val);
1661 break;
1662
1663 case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1664 val = vsk->buffer_min_size;
1665 COPY_OUT(val);
1666 break;
1667
1668 case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1669 struct __kernel_old_timeval tv;
1670 tv.tv_sec = vsk->connect_timeout / HZ;
1671 tv.tv_usec =
1672 (vsk->connect_timeout -
1673 tv.tv_sec * HZ) * (1000000 / HZ);
1674 COPY_OUT(tv);
1675 break;
1676 }
1677 default:
1678 return -ENOPROTOOPT;
1679 }
1680
1681 err = put_user(len, optlen);
1682 if (err != 0)
1683 return -EFAULT;
1684
1685 #undef COPY_OUT
1686
1687 return 0;
1688 }
1689
vsock_stream_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)1690 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
1691 size_t len)
1692 {
1693 struct sock *sk;
1694 struct vsock_sock *vsk;
1695 const struct vsock_transport *transport;
1696 ssize_t total_written;
1697 long timeout;
1698 int err;
1699 struct vsock_transport_send_notify_data send_data;
1700 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1701
1702 sk = sock->sk;
1703 vsk = vsock_sk(sk);
1704 total_written = 0;
1705 err = 0;
1706
1707 if (msg->msg_flags & MSG_OOB)
1708 return -EOPNOTSUPP;
1709
1710 lock_sock(sk);
1711
1712 transport = vsk->transport;
1713
1714 /* Callers should not provide a destination with stream sockets. */
1715 if (msg->msg_namelen) {
1716 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
1717 goto out;
1718 }
1719
1720 /* Send data only if both sides are not shutdown in the direction. */
1721 if (sk->sk_shutdown & SEND_SHUTDOWN ||
1722 vsk->peer_shutdown & RCV_SHUTDOWN) {
1723 err = -EPIPE;
1724 goto out;
1725 }
1726
1727 if (!transport || sk->sk_state != TCP_ESTABLISHED ||
1728 !vsock_addr_bound(&vsk->local_addr)) {
1729 err = -ENOTCONN;
1730 goto out;
1731 }
1732
1733 if (!vsock_addr_bound(&vsk->remote_addr)) {
1734 err = -EDESTADDRREQ;
1735 goto out;
1736 }
1737
1738 /* Wait for room in the produce queue to enqueue our user's data. */
1739 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1740
1741 err = transport->notify_send_init(vsk, &send_data);
1742 if (err < 0)
1743 goto out;
1744
1745 while (total_written < len) {
1746 ssize_t written;
1747
1748 add_wait_queue(sk_sleep(sk), &wait);
1749 while (vsock_stream_has_space(vsk) == 0 &&
1750 sk->sk_err == 0 &&
1751 !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1752 !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1753
1754 /* Don't wait for non-blocking sockets. */
1755 if (timeout == 0) {
1756 err = -EAGAIN;
1757 remove_wait_queue(sk_sleep(sk), &wait);
1758 goto out_err;
1759 }
1760
1761 err = transport->notify_send_pre_block(vsk, &send_data);
1762 if (err < 0) {
1763 remove_wait_queue(sk_sleep(sk), &wait);
1764 goto out_err;
1765 }
1766
1767 release_sock(sk);
1768 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
1769 lock_sock(sk);
1770 if (signal_pending(current)) {
1771 err = sock_intr_errno(timeout);
1772 remove_wait_queue(sk_sleep(sk), &wait);
1773 goto out_err;
1774 } else if (timeout == 0) {
1775 err = -EAGAIN;
1776 remove_wait_queue(sk_sleep(sk), &wait);
1777 goto out_err;
1778 }
1779 }
1780 remove_wait_queue(sk_sleep(sk), &wait);
1781
1782 /* These checks occur both as part of and after the loop
1783 * conditional since we need to check before and after
1784 * sleeping.
1785 */
1786 if (sk->sk_err) {
1787 err = -sk->sk_err;
1788 goto out_err;
1789 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1790 (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1791 err = -EPIPE;
1792 goto out_err;
1793 }
1794
1795 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1796 if (err < 0)
1797 goto out_err;
1798
1799 /* Note that enqueue will only write as many bytes as are free
1800 * in the produce queue, so we don't need to ensure len is
1801 * smaller than the queue size. It is the caller's
1802 * responsibility to check how many bytes we were able to send.
1803 */
1804
1805 written = transport->stream_enqueue(
1806 vsk, msg,
1807 len - total_written);
1808 if (written < 0) {
1809 err = -ENOMEM;
1810 goto out_err;
1811 }
1812
1813 total_written += written;
1814
1815 err = transport->notify_send_post_enqueue(
1816 vsk, written, &send_data);
1817 if (err < 0)
1818 goto out_err;
1819
1820 }
1821
1822 out_err:
1823 if (total_written > 0)
1824 err = total_written;
1825 out:
1826 release_sock(sk);
1827 return err;
1828 }
1829
1830
1831 static int
vsock_stream_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)1832 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1833 int flags)
1834 {
1835 struct sock *sk;
1836 struct vsock_sock *vsk;
1837 const struct vsock_transport *transport;
1838 int err;
1839 size_t target;
1840 ssize_t copied;
1841 long timeout;
1842 struct vsock_transport_recv_notify_data recv_data;
1843
1844 DEFINE_WAIT(wait);
1845
1846 sk = sock->sk;
1847 vsk = vsock_sk(sk);
1848 err = 0;
1849
1850 lock_sock(sk);
1851
1852 transport = vsk->transport;
1853
1854 if (!transport || sk->sk_state != TCP_ESTABLISHED) {
1855 /* Recvmsg is supposed to return 0 if a peer performs an
1856 * orderly shutdown. Differentiate between that case and when a
1857 * peer has not connected or a local shutdown occured with the
1858 * SOCK_DONE flag.
1859 */
1860 if (sock_flag(sk, SOCK_DONE))
1861 err = 0;
1862 else
1863 err = -ENOTCONN;
1864
1865 goto out;
1866 }
1867
1868 if (flags & MSG_OOB) {
1869 err = -EOPNOTSUPP;
1870 goto out;
1871 }
1872
1873 /* We don't check peer_shutdown flag here since peer may actually shut
1874 * down, but there can be data in the queue that a local socket can
1875 * receive.
1876 */
1877 if (sk->sk_shutdown & RCV_SHUTDOWN) {
1878 err = 0;
1879 goto out;
1880 }
1881
1882 /* It is valid on Linux to pass in a zero-length receive buffer. This
1883 * is not an error. We may as well bail out now.
1884 */
1885 if (!len) {
1886 err = 0;
1887 goto out;
1888 }
1889
1890 /* We must not copy less than target bytes into the user's buffer
1891 * before returning successfully, so we wait for the consume queue to
1892 * have that much data to consume before dequeueing. Note that this
1893 * makes it impossible to handle cases where target is greater than the
1894 * queue size.
1895 */
1896 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1897 if (target >= transport->stream_rcvhiwat(vsk)) {
1898 err = -ENOMEM;
1899 goto out;
1900 }
1901 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1902 copied = 0;
1903
1904 err = transport->notify_recv_init(vsk, target, &recv_data);
1905 if (err < 0)
1906 goto out;
1907
1908
1909 while (1) {
1910 s64 ready;
1911
1912 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1913 ready = vsock_stream_has_data(vsk);
1914
1915 if (ready == 0) {
1916 if (sk->sk_err != 0 ||
1917 (sk->sk_shutdown & RCV_SHUTDOWN) ||
1918 (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1919 finish_wait(sk_sleep(sk), &wait);
1920 break;
1921 }
1922 /* Don't wait for non-blocking sockets. */
1923 if (timeout == 0) {
1924 err = -EAGAIN;
1925 finish_wait(sk_sleep(sk), &wait);
1926 break;
1927 }
1928
1929 err = transport->notify_recv_pre_block(
1930 vsk, target, &recv_data);
1931 if (err < 0) {
1932 finish_wait(sk_sleep(sk), &wait);
1933 break;
1934 }
1935 release_sock(sk);
1936 timeout = schedule_timeout(timeout);
1937 lock_sock(sk);
1938
1939 if (signal_pending(current)) {
1940 err = sock_intr_errno(timeout);
1941 finish_wait(sk_sleep(sk), &wait);
1942 break;
1943 } else if (timeout == 0) {
1944 err = -EAGAIN;
1945 finish_wait(sk_sleep(sk), &wait);
1946 break;
1947 }
1948 } else {
1949 ssize_t read;
1950
1951 finish_wait(sk_sleep(sk), &wait);
1952
1953 if (ready < 0) {
1954 /* Invalid queue pair content. XXX This should
1955 * be changed to a connection reset in a later
1956 * change.
1957 */
1958
1959 err = -ENOMEM;
1960 goto out;
1961 }
1962
1963 err = transport->notify_recv_pre_dequeue(
1964 vsk, target, &recv_data);
1965 if (err < 0)
1966 break;
1967
1968 read = transport->stream_dequeue(
1969 vsk, msg,
1970 len - copied, flags);
1971 if (read < 0) {
1972 err = -ENOMEM;
1973 break;
1974 }
1975
1976 copied += read;
1977
1978 err = transport->notify_recv_post_dequeue(
1979 vsk, target, read,
1980 !(flags & MSG_PEEK), &recv_data);
1981 if (err < 0)
1982 goto out;
1983
1984 if (read >= target || flags & MSG_PEEK)
1985 break;
1986
1987 target -= read;
1988 }
1989 }
1990
1991 if (sk->sk_err)
1992 err = -sk->sk_err;
1993 else if (sk->sk_shutdown & RCV_SHUTDOWN)
1994 err = 0;
1995
1996 if (copied > 0)
1997 err = copied;
1998
1999 out:
2000 release_sock(sk);
2001 return err;
2002 }
2003
2004 static const struct proto_ops vsock_stream_ops = {
2005 .family = PF_VSOCK,
2006 .owner = THIS_MODULE,
2007 .release = vsock_release,
2008 .bind = vsock_bind,
2009 .connect = vsock_stream_connect,
2010 .socketpair = sock_no_socketpair,
2011 .accept = vsock_accept,
2012 .getname = vsock_getname,
2013 .poll = vsock_poll,
2014 .ioctl = sock_no_ioctl,
2015 .listen = vsock_listen,
2016 .shutdown = vsock_shutdown,
2017 .setsockopt = vsock_stream_setsockopt,
2018 .getsockopt = vsock_stream_getsockopt,
2019 .sendmsg = vsock_stream_sendmsg,
2020 .recvmsg = vsock_stream_recvmsg,
2021 .mmap = sock_no_mmap,
2022 .sendpage = sock_no_sendpage,
2023 };
2024
vsock_create(struct net * net,struct socket * sock,int protocol,int kern)2025 static int vsock_create(struct net *net, struct socket *sock,
2026 int protocol, int kern)
2027 {
2028 struct vsock_sock *vsk;
2029 struct sock *sk;
2030 int ret;
2031
2032 if (!sock)
2033 return -EINVAL;
2034
2035 if (protocol && protocol != PF_VSOCK)
2036 return -EPROTONOSUPPORT;
2037
2038 switch (sock->type) {
2039 case SOCK_DGRAM:
2040 sock->ops = &vsock_dgram_ops;
2041 break;
2042 case SOCK_STREAM:
2043 sock->ops = &vsock_stream_ops;
2044 break;
2045 default:
2046 return -ESOCKTNOSUPPORT;
2047 }
2048
2049 sock->state = SS_UNCONNECTED;
2050
2051 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern);
2052 if (!sk)
2053 return -ENOMEM;
2054
2055 vsk = vsock_sk(sk);
2056
2057 if (sock->type == SOCK_DGRAM) {
2058 ret = vsock_assign_transport(vsk, NULL);
2059 if (ret < 0) {
2060 sock_put(sk);
2061 return ret;
2062 }
2063 }
2064
2065 vsock_insert_unbound(vsk);
2066
2067 return 0;
2068 }
2069
2070 static const struct net_proto_family vsock_family_ops = {
2071 .family = AF_VSOCK,
2072 .create = vsock_create,
2073 .owner = THIS_MODULE,
2074 };
2075
vsock_dev_do_ioctl(struct file * filp,unsigned int cmd,void __user * ptr)2076 static long vsock_dev_do_ioctl(struct file *filp,
2077 unsigned int cmd, void __user *ptr)
2078 {
2079 u32 __user *p = ptr;
2080 u32 cid = VMADDR_CID_ANY;
2081 int retval = 0;
2082
2083 switch (cmd) {
2084 case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
2085 /* To be compatible with the VMCI behavior, we prioritize the
2086 * guest CID instead of well-know host CID (VMADDR_CID_HOST).
2087 */
2088 if (transport_g2h)
2089 cid = transport_g2h->get_local_cid();
2090 else if (transport_h2g)
2091 cid = transport_h2g->get_local_cid();
2092
2093 if (put_user(cid, p) != 0)
2094 retval = -EFAULT;
2095 break;
2096
2097 default:
2098 pr_err("Unknown ioctl %d\n", cmd);
2099 retval = -EINVAL;
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