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. */ 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 } 191 192 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 } 202 203 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 } 209 210 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 } 216 217 static void __vsock_remove_bound(struct vsock_sock *vsk) 218 { 219 list_del_init(&vsk->bound_table); 220 sock_put(&vsk->sk); 221 } 222 223 static void __vsock_remove_connected(struct vsock_sock *vsk) 224 { 225 list_del_init(&vsk->connected_table); 226 sock_put(&vsk->sk); 227 } 228 229 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 } 245 246 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 } 261 262 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 } 268 269 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); 279 280 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); 288 289 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); 297 298 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); 312 313 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); 328 329 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); 335 336 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); 352 353 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); 366 367 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); 376 377 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); 390 391 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 } 405 406 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 */ 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); 498 499 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); 513 514 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 } 535 536 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 } 541 542 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 } 547 548 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 } 557 558 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 ****/ 606 607 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 } 661 662 static int __vsock_bind_dgram(struct vsock_sock *vsk, 663 struct sockaddr_vm *addr) 664 { 665 return vsk->transport->dgram_bind(vsk, addr); 666 } 667 668 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); 705 706 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 } else { 759 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN); 760 vsk->owner = get_current_cred(); 761 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 762 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE; 763 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE; 764 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE; 765 } 766 767 return sk; 768 } 769 770 static void __vsock_release(struct sock *sk, int level) 771 { 772 if (sk) { 773 struct sock *pending; 774 struct vsock_sock *vsk; 775 776 vsk = vsock_sk(sk); 777 pending = NULL; /* Compiler warning. */ 778 779 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 780 * version to avoid the warning "possible recursive locking 781 * detected". When "level" is 0, lock_sock_nested(sk, level) 782 * is the same as lock_sock(sk). 783 */ 784 lock_sock_nested(sk, level); 785 786 if (vsk->transport) 787 vsk->transport->release(vsk); 788 else if (sk->sk_type == SOCK_STREAM) 789 vsock_remove_sock(vsk); 790 791 sock_orphan(sk); 792 sk->sk_shutdown = SHUTDOWN_MASK; 793 794 skb_queue_purge(&sk->sk_receive_queue); 795 796 /* Clean up any sockets that never were accepted. */ 797 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 798 __vsock_release(pending, SINGLE_DEPTH_NESTING); 799 sock_put(pending); 800 } 801 802 release_sock(sk); 803 sock_put(sk); 804 } 805 } 806 807 static void vsock_sk_destruct(struct sock *sk) 808 { 809 struct vsock_sock *vsk = vsock_sk(sk); 810 811 vsock_deassign_transport(vsk); 812 813 /* When clearing these addresses, there's no need to set the family and 814 * possibly register the address family with the kernel. 815 */ 816 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 817 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 818 819 put_cred(vsk->owner); 820 } 821 822 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 823 { 824 int err; 825 826 err = sock_queue_rcv_skb(sk, skb); 827 if (err) 828 kfree_skb(skb); 829 830 return err; 831 } 832 833 struct sock *vsock_create_connected(struct sock *parent) 834 { 835 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL, 836 parent->sk_type, 0); 837 } 838 EXPORT_SYMBOL_GPL(vsock_create_connected); 839 840 s64 vsock_stream_has_data(struct vsock_sock *vsk) 841 { 842 return vsk->transport->stream_has_data(vsk); 843 } 844 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 845 846 s64 vsock_stream_has_space(struct vsock_sock *vsk) 847 { 848 return vsk->transport->stream_has_space(vsk); 849 } 850 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 851 852 static int vsock_release(struct socket *sock) 853 { 854 __vsock_release(sock->sk, 0); 855 sock->sk = NULL; 856 sock->state = SS_FREE; 857 858 return 0; 859 } 860 861 static int 862 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 863 { 864 int err; 865 struct sock *sk; 866 struct sockaddr_vm *vm_addr; 867 868 sk = sock->sk; 869 870 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 871 return -EINVAL; 872 873 lock_sock(sk); 874 err = __vsock_bind(sk, vm_addr); 875 release_sock(sk); 876 877 return err; 878 } 879 880 static int vsock_getname(struct socket *sock, 881 struct sockaddr *addr, int peer) 882 { 883 int err; 884 struct sock *sk; 885 struct vsock_sock *vsk; 886 struct sockaddr_vm *vm_addr; 887 888 sk = sock->sk; 889 vsk = vsock_sk(sk); 890 err = 0; 891 892 lock_sock(sk); 893 894 if (peer) { 895 if (sock->state != SS_CONNECTED) { 896 err = -ENOTCONN; 897 goto out; 898 } 899 vm_addr = &vsk->remote_addr; 900 } else { 901 vm_addr = &vsk->local_addr; 902 } 903 904 if (!vm_addr) { 905 err = -EINVAL; 906 goto out; 907 } 908 909 /* sys_getsockname() and sys_getpeername() pass us a 910 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 911 * that macro is defined in socket.c instead of .h, so we hardcode its 912 * value here. 913 */ 914 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 915 memcpy(addr, vm_addr, sizeof(*vm_addr)); 916 err = sizeof(*vm_addr); 917 918 out: 919 release_sock(sk); 920 return err; 921 } 922 923 static int vsock_shutdown(struct socket *sock, int mode) 924 { 925 int err; 926 struct sock *sk; 927 928 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 929 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 930 * here like the other address families do. Note also that the 931 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 932 * which is what we want. 933 */ 934 mode++; 935 936 if ((mode & ~SHUTDOWN_MASK) || !mode) 937 return -EINVAL; 938 939 /* If this is a STREAM socket and it is not connected then bail out 940 * immediately. If it is a DGRAM socket then we must first kick the 941 * socket so that it wakes up from any sleeping calls, for example 942 * recv(), and then afterwards return the error. 943 */ 944 945 sk = sock->sk; 946 if (sock->state == SS_UNCONNECTED) { 947 err = -ENOTCONN; 948 if (sk->sk_type == SOCK_STREAM) 949 return err; 950 } else { 951 sock->state = SS_DISCONNECTING; 952 err = 0; 953 } 954 955 /* Receive and send shutdowns are treated alike. */ 956 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 957 if (mode) { 958 lock_sock(sk); 959 sk->sk_shutdown |= mode; 960 sk->sk_state_change(sk); 961 release_sock(sk); 962 963 if (sk->sk_type == SOCK_STREAM) { 964 sock_reset_flag(sk, SOCK_DONE); 965 vsock_send_shutdown(sk, mode); 966 } 967 } 968 969 return err; 970 } 971 972 static __poll_t vsock_poll(struct file *file, struct socket *sock, 973 poll_table *wait) 974 { 975 struct sock *sk; 976 __poll_t mask; 977 struct vsock_sock *vsk; 978 979 sk = sock->sk; 980 vsk = vsock_sk(sk); 981 982 poll_wait(file, sk_sleep(sk), wait); 983 mask = 0; 984 985 if (sk->sk_err) 986 /* Signify that there has been an error on this socket. */ 987 mask |= EPOLLERR; 988 989 /* INET sockets treat local write shutdown and peer write shutdown as a 990 * case of EPOLLHUP set. 991 */ 992 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 993 ((sk->sk_shutdown & SEND_SHUTDOWN) && 994 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 995 mask |= EPOLLHUP; 996 } 997 998 if (sk->sk_shutdown & RCV_SHUTDOWN || 999 vsk->peer_shutdown & SEND_SHUTDOWN) { 1000 mask |= EPOLLRDHUP; 1001 } 1002 1003 if (sock->type == SOCK_DGRAM) { 1004 /* For datagram sockets we can read if there is something in 1005 * the queue and write as long as the socket isn't shutdown for 1006 * sending. 1007 */ 1008 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 1009 (sk->sk_shutdown & RCV_SHUTDOWN)) { 1010 mask |= EPOLLIN | EPOLLRDNORM; 1011 } 1012 1013 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1014 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 1015 1016 } else if (sock->type == SOCK_STREAM) { 1017 const struct vsock_transport *transport = vsk->transport; 1018 lock_sock(sk); 1019 1020 /* Listening sockets that have connections in their accept 1021 * queue can be read. 1022 */ 1023 if (sk->sk_state == TCP_LISTEN 1024 && !vsock_is_accept_queue_empty(sk)) 1025 mask |= EPOLLIN | EPOLLRDNORM; 1026 1027 /* If there is something in the queue then we can read. */ 1028 if (transport && transport->stream_is_active(vsk) && 1029 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1030 bool data_ready_now = false; 1031 int ret = transport->notify_poll_in( 1032 vsk, 1, &data_ready_now); 1033 if (ret < 0) { 1034 mask |= EPOLLERR; 1035 } else { 1036 if (data_ready_now) 1037 mask |= EPOLLIN | EPOLLRDNORM; 1038 1039 } 1040 } 1041 1042 /* Sockets whose connections have been closed, reset, or 1043 * terminated should also be considered read, and we check the 1044 * shutdown flag for that. 1045 */ 1046 if (sk->sk_shutdown & RCV_SHUTDOWN || 1047 vsk->peer_shutdown & SEND_SHUTDOWN) { 1048 mask |= EPOLLIN | EPOLLRDNORM; 1049 } 1050 1051 /* Connected sockets that can produce data can be written. */ 1052 if (transport && sk->sk_state == TCP_ESTABLISHED) { 1053 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1054 bool space_avail_now = false; 1055 int ret = transport->notify_poll_out( 1056 vsk, 1, &space_avail_now); 1057 if (ret < 0) { 1058 mask |= EPOLLERR; 1059 } else { 1060 if (space_avail_now) 1061 /* Remove EPOLLWRBAND since INET 1062 * sockets are not setting it. 1063 */ 1064 mask |= EPOLLOUT | EPOLLWRNORM; 1065 1066 } 1067 } 1068 } 1069 1070 /* Simulate INET socket poll behaviors, which sets 1071 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 1072 * but local send is not shutdown. 1073 */ 1074 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 1075 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1076 mask |= EPOLLOUT | EPOLLWRNORM; 1077 1078 } 1079 1080 release_sock(sk); 1081 } 1082 1083 return mask; 1084 } 1085 1086 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 1087 size_t len) 1088 { 1089 int err; 1090 struct sock *sk; 1091 struct vsock_sock *vsk; 1092 struct sockaddr_vm *remote_addr; 1093 const struct vsock_transport *transport; 1094 1095 if (msg->msg_flags & MSG_OOB) 1096 return -EOPNOTSUPP; 1097 1098 /* For now, MSG_DONTWAIT is always assumed... */ 1099 err = 0; 1100 sk = sock->sk; 1101 vsk = vsock_sk(sk); 1102 transport = vsk->transport; 1103 1104 lock_sock(sk); 1105 1106 err = vsock_auto_bind(vsk); 1107 if (err) 1108 goto out; 1109 1110 1111 /* If the provided message contains an address, use that. Otherwise 1112 * fall back on the socket's remote handle (if it has been connected). 1113 */ 1114 if (msg->msg_name && 1115 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 1116 &remote_addr) == 0) { 1117 /* Ensure this address is of the right type and is a valid 1118 * destination. 1119 */ 1120 1121 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1122 remote_addr->svm_cid = transport->get_local_cid(); 1123 1124 if (!vsock_addr_bound(remote_addr)) { 1125 err = -EINVAL; 1126 goto out; 1127 } 1128 } else if (sock->state == SS_CONNECTED) { 1129 remote_addr = &vsk->remote_addr; 1130 1131 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1132 remote_addr->svm_cid = transport->get_local_cid(); 1133 1134 /* XXX Should connect() or this function ensure remote_addr is 1135 * bound? 1136 */ 1137 if (!vsock_addr_bound(&vsk->remote_addr)) { 1138 err = -EINVAL; 1139 goto out; 1140 } 1141 } else { 1142 err = -EINVAL; 1143 goto out; 1144 } 1145 1146 if (!transport->dgram_allow(remote_addr->svm_cid, 1147 remote_addr->svm_port)) { 1148 err = -EINVAL; 1149 goto out; 1150 } 1151 1152 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1153 1154 out: 1155 release_sock(sk); 1156 return err; 1157 } 1158 1159 static int vsock_dgram_connect(struct socket *sock, 1160 struct sockaddr *addr, int addr_len, int flags) 1161 { 1162 int err; 1163 struct sock *sk; 1164 struct vsock_sock *vsk; 1165 struct sockaddr_vm *remote_addr; 1166 1167 sk = sock->sk; 1168 vsk = vsock_sk(sk); 1169 1170 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1171 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1172 lock_sock(sk); 1173 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1174 VMADDR_PORT_ANY); 1175 sock->state = SS_UNCONNECTED; 1176 release_sock(sk); 1177 return 0; 1178 } else if (err != 0) 1179 return -EINVAL; 1180 1181 lock_sock(sk); 1182 1183 err = vsock_auto_bind(vsk); 1184 if (err) 1185 goto out; 1186 1187 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1188 remote_addr->svm_port)) { 1189 err = -EINVAL; 1190 goto out; 1191 } 1192 1193 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1194 sock->state = SS_CONNECTED; 1195 1196 out: 1197 release_sock(sk); 1198 return err; 1199 } 1200 1201 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1202 size_t len, int flags) 1203 { 1204 struct vsock_sock *vsk = vsock_sk(sock->sk); 1205 1206 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1207 } 1208 1209 static const struct proto_ops vsock_dgram_ops = { 1210 .family = PF_VSOCK, 1211 .owner = THIS_MODULE, 1212 .release = vsock_release, 1213 .bind = vsock_bind, 1214 .connect = vsock_dgram_connect, 1215 .socketpair = sock_no_socketpair, 1216 .accept = sock_no_accept, 1217 .getname = vsock_getname, 1218 .poll = vsock_poll, 1219 .ioctl = sock_no_ioctl, 1220 .listen = sock_no_listen, 1221 .shutdown = vsock_shutdown, 1222 .sendmsg = vsock_dgram_sendmsg, 1223 .recvmsg = vsock_dgram_recvmsg, 1224 .mmap = sock_no_mmap, 1225 .sendpage = sock_no_sendpage, 1226 }; 1227 1228 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1229 { 1230 const struct vsock_transport *transport = vsk->transport; 1231 1232 if (!transport->cancel_pkt) 1233 return -EOPNOTSUPP; 1234 1235 return transport->cancel_pkt(vsk); 1236 } 1237 1238 static void vsock_connect_timeout(struct work_struct *work) 1239 { 1240 struct sock *sk; 1241 struct vsock_sock *vsk; 1242 int cancel = 0; 1243 1244 vsk = container_of(work, struct vsock_sock, connect_work.work); 1245 sk = sk_vsock(vsk); 1246 1247 lock_sock(sk); 1248 if (sk->sk_state == TCP_SYN_SENT && 1249 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1250 sk->sk_state = TCP_CLOSE; 1251 sk->sk_err = ETIMEDOUT; 1252 sk->sk_error_report(sk); 1253 cancel = 1; 1254 } 1255 release_sock(sk); 1256 if (cancel) 1257 vsock_transport_cancel_pkt(vsk); 1258 1259 sock_put(sk); 1260 } 1261 1262 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr, 1263 int addr_len, int flags) 1264 { 1265 int err; 1266 struct sock *sk; 1267 struct vsock_sock *vsk; 1268 const struct vsock_transport *transport; 1269 struct sockaddr_vm *remote_addr; 1270 long timeout; 1271 DEFINE_WAIT(wait); 1272 1273 err = 0; 1274 sk = sock->sk; 1275 vsk = vsock_sk(sk); 1276 1277 lock_sock(sk); 1278 1279 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1280 switch (sock->state) { 1281 case SS_CONNECTED: 1282 err = -EISCONN; 1283 goto out; 1284 case SS_DISCONNECTING: 1285 err = -EINVAL; 1286 goto out; 1287 case SS_CONNECTING: 1288 /* This continues on so we can move sock into the SS_CONNECTED 1289 * state once the connection has completed (at which point err 1290 * will be set to zero also). Otherwise, we will either wait 1291 * for the connection or return -EALREADY should this be a 1292 * non-blocking call. 1293 */ 1294 err = -EALREADY; 1295 break; 1296 default: 1297 if ((sk->sk_state == TCP_LISTEN) || 1298 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1299 err = -EINVAL; 1300 goto out; 1301 } 1302 1303 /* Set the remote address that we are connecting to. */ 1304 memcpy(&vsk->remote_addr, remote_addr, 1305 sizeof(vsk->remote_addr)); 1306 1307 err = vsock_assign_transport(vsk, NULL); 1308 if (err) 1309 goto out; 1310 1311 transport = vsk->transport; 1312 1313 /* The hypervisor and well-known contexts do not have socket 1314 * endpoints. 1315 */ 1316 if (!transport || 1317 !transport->stream_allow(remote_addr->svm_cid, 1318 remote_addr->svm_port)) { 1319 err = -ENETUNREACH; 1320 goto out; 1321 } 1322 1323 err = vsock_auto_bind(vsk); 1324 if (err) 1325 goto out; 1326 1327 sk->sk_state = TCP_SYN_SENT; 1328 1329 err = transport->connect(vsk); 1330 if (err < 0) 1331 goto out; 1332 1333 /* Mark sock as connecting and set the error code to in 1334 * progress in case this is a non-blocking connect. 1335 */ 1336 sock->state = SS_CONNECTING; 1337 err = -EINPROGRESS; 1338 } 1339 1340 /* The receive path will handle all communication until we are able to 1341 * enter the connected state. Here we wait for the connection to be 1342 * completed or a notification of an error. 1343 */ 1344 timeout = vsk->connect_timeout; 1345 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1346 1347 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1348 if (flags & O_NONBLOCK) { 1349 /* If we're not going to block, we schedule a timeout 1350 * function to generate a timeout on the connection 1351 * attempt, in case the peer doesn't respond in a 1352 * timely manner. We hold on to the socket until the 1353 * timeout fires. 1354 */ 1355 sock_hold(sk); 1356 schedule_delayed_work(&vsk->connect_work, timeout); 1357 1358 /* Skip ahead to preserve error code set above. */ 1359 goto out_wait; 1360 } 1361 1362 release_sock(sk); 1363 timeout = schedule_timeout(timeout); 1364 lock_sock(sk); 1365 1366 if (signal_pending(current)) { 1367 err = sock_intr_errno(timeout); 1368 sk->sk_state = TCP_CLOSE; 1369 sock->state = SS_UNCONNECTED; 1370 vsock_transport_cancel_pkt(vsk); 1371 goto out_wait; 1372 } else if (timeout == 0) { 1373 err = -ETIMEDOUT; 1374 sk->sk_state = TCP_CLOSE; 1375 sock->state = SS_UNCONNECTED; 1376 vsock_transport_cancel_pkt(vsk); 1377 goto out_wait; 1378 } 1379 1380 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1381 } 1382 1383 if (sk->sk_err) { 1384 err = -sk->sk_err; 1385 sk->sk_state = TCP_CLOSE; 1386 sock->state = SS_UNCONNECTED; 1387 } else { 1388 err = 0; 1389 } 1390 1391 out_wait: 1392 finish_wait(sk_sleep(sk), &wait); 1393 out: 1394 release_sock(sk); 1395 return err; 1396 } 1397 1398 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1399 bool kern) 1400 { 1401 struct sock *listener; 1402 int err; 1403 struct sock *connected; 1404 struct vsock_sock *vconnected; 1405 long timeout; 1406 DEFINE_WAIT(wait); 1407 1408 err = 0; 1409 listener = sock->sk; 1410 1411 lock_sock(listener); 1412 1413 if (sock->type != SOCK_STREAM) { 1414 err = -EOPNOTSUPP; 1415 goto out; 1416 } 1417 1418 if (listener->sk_state != TCP_LISTEN) { 1419 err = -EINVAL; 1420 goto out; 1421 } 1422 1423 /* Wait for children sockets to appear; these are the new sockets 1424 * created upon connection establishment. 1425 */ 1426 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1427 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1428 1429 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1430 listener->sk_err == 0) { 1431 release_sock(listener); 1432 timeout = schedule_timeout(timeout); 1433 finish_wait(sk_sleep(listener), &wait); 1434 lock_sock(listener); 1435 1436 if (signal_pending(current)) { 1437 err = sock_intr_errno(timeout); 1438 goto out; 1439 } else if (timeout == 0) { 1440 err = -EAGAIN; 1441 goto out; 1442 } 1443 1444 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1445 } 1446 finish_wait(sk_sleep(listener), &wait); 1447 1448 if (listener->sk_err) 1449 err = -listener->sk_err; 1450 1451 if (connected) { 1452 sk_acceptq_removed(listener); 1453 1454 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1455 vconnected = vsock_sk(connected); 1456 1457 /* If the listener socket has received an error, then we should 1458 * reject this socket and return. Note that we simply mark the 1459 * socket rejected, drop our reference, and let the cleanup 1460 * function handle the cleanup; the fact that we found it in 1461 * the listener's accept queue guarantees that the cleanup 1462 * function hasn't run yet. 1463 */ 1464 if (err) { 1465 vconnected->rejected = true; 1466 } else { 1467 newsock->state = SS_CONNECTED; 1468 sock_graft(connected, newsock); 1469 } 1470 1471 release_sock(connected); 1472 sock_put(connected); 1473 } 1474 1475 out: 1476 release_sock(listener); 1477 return err; 1478 } 1479 1480 static int vsock_listen(struct socket *sock, int backlog) 1481 { 1482 int err; 1483 struct sock *sk; 1484 struct vsock_sock *vsk; 1485 1486 sk = sock->sk; 1487 1488 lock_sock(sk); 1489 1490 if (sock->type != SOCK_STREAM) { 1491 err = -EOPNOTSUPP; 1492 goto out; 1493 } 1494 1495 if (sock->state != SS_UNCONNECTED) { 1496 err = -EINVAL; 1497 goto out; 1498 } 1499 1500 vsk = vsock_sk(sk); 1501 1502 if (!vsock_addr_bound(&vsk->local_addr)) { 1503 err = -EINVAL; 1504 goto out; 1505 } 1506 1507 sk->sk_max_ack_backlog = backlog; 1508 sk->sk_state = TCP_LISTEN; 1509 1510 err = 0; 1511 1512 out: 1513 release_sock(sk); 1514 return err; 1515 } 1516 1517 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1518 const struct vsock_transport *transport, 1519 u64 val) 1520 { 1521 if (val > vsk->buffer_max_size) 1522 val = vsk->buffer_max_size; 1523 1524 if (val < vsk->buffer_min_size) 1525 val = vsk->buffer_min_size; 1526 1527 if (val != vsk->buffer_size && 1528 transport && transport->notify_buffer_size) 1529 transport->notify_buffer_size(vsk, &val); 1530 1531 vsk->buffer_size = val; 1532 } 1533 1534 static int vsock_stream_setsockopt(struct socket *sock, 1535 int level, 1536 int optname, 1537 sockptr_t optval, 1538 unsigned int optlen) 1539 { 1540 int err; 1541 struct sock *sk; 1542 struct vsock_sock *vsk; 1543 const struct vsock_transport *transport; 1544 u64 val; 1545 1546 if (level != AF_VSOCK) 1547 return -ENOPROTOOPT; 1548 1549 #define COPY_IN(_v) \ 1550 do { \ 1551 if (optlen < sizeof(_v)) { \ 1552 err = -EINVAL; \ 1553 goto exit; \ 1554 } \ 1555 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1556 err = -EFAULT; \ 1557 goto exit; \ 1558 } \ 1559 } while (0) 1560 1561 err = 0; 1562 sk = sock->sk; 1563 vsk = vsock_sk(sk); 1564 transport = vsk->transport; 1565 1566 lock_sock(sk); 1567 1568 switch (optname) { 1569 case SO_VM_SOCKETS_BUFFER_SIZE: 1570 COPY_IN(val); 1571 vsock_update_buffer_size(vsk, transport, val); 1572 break; 1573 1574 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1575 COPY_IN(val); 1576 vsk->buffer_max_size = val; 1577 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1578 break; 1579 1580 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1581 COPY_IN(val); 1582 vsk->buffer_min_size = val; 1583 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1584 break; 1585 1586 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1587 struct __kernel_old_timeval tv; 1588 COPY_IN(tv); 1589 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1590 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1591 vsk->connect_timeout = tv.tv_sec * HZ + 1592 DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ)); 1593 if (vsk->connect_timeout == 0) 1594 vsk->connect_timeout = 1595 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1596 1597 } else { 1598 err = -ERANGE; 1599 } 1600 break; 1601 } 1602 1603 default: 1604 err = -ENOPROTOOPT; 1605 break; 1606 } 1607 1608 #undef COPY_IN 1609 1610 exit: 1611 release_sock(sk); 1612 return err; 1613 } 1614 1615 static int vsock_stream_getsockopt(struct socket *sock, 1616 int level, int optname, 1617 char __user *optval, 1618 int __user *optlen) 1619 { 1620 int err; 1621 int len; 1622 struct sock *sk; 1623 struct vsock_sock *vsk; 1624 u64 val; 1625 1626 if (level != AF_VSOCK) 1627 return -ENOPROTOOPT; 1628 1629 err = get_user(len, optlen); 1630 if (err != 0) 1631 return err; 1632 1633 #define COPY_OUT(_v) \ 1634 do { \ 1635 if (len < sizeof(_v)) \ 1636 return -EINVAL; \ 1637 \ 1638 len = sizeof(_v); \ 1639 if (copy_to_user(optval, &_v, len) != 0) \ 1640 return -EFAULT; \ 1641 \ 1642 } while (0) 1643 1644 err = 0; 1645 sk = sock->sk; 1646 vsk = vsock_sk(sk); 1647 1648 switch (optname) { 1649 case SO_VM_SOCKETS_BUFFER_SIZE: 1650 val = vsk->buffer_size; 1651 COPY_OUT(val); 1652 break; 1653 1654 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1655 val = vsk->buffer_max_size; 1656 COPY_OUT(val); 1657 break; 1658 1659 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1660 val = vsk->buffer_min_size; 1661 COPY_OUT(val); 1662 break; 1663 1664 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1665 struct __kernel_old_timeval tv; 1666 tv.tv_sec = vsk->connect_timeout / HZ; 1667 tv.tv_usec = 1668 (vsk->connect_timeout - 1669 tv.tv_sec * HZ) * (1000000 / HZ); 1670 COPY_OUT(tv); 1671 break; 1672 } 1673 default: 1674 return -ENOPROTOOPT; 1675 } 1676 1677 err = put_user(len, optlen); 1678 if (err != 0) 1679 return -EFAULT; 1680 1681 #undef COPY_OUT 1682 1683 return 0; 1684 } 1685 1686 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, 1687 size_t len) 1688 { 1689 struct sock *sk; 1690 struct vsock_sock *vsk; 1691 const struct vsock_transport *transport; 1692 ssize_t total_written; 1693 long timeout; 1694 int err; 1695 struct vsock_transport_send_notify_data send_data; 1696 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1697 1698 sk = sock->sk; 1699 vsk = vsock_sk(sk); 1700 transport = vsk->transport; 1701 total_written = 0; 1702 err = 0; 1703 1704 if (msg->msg_flags & MSG_OOB) 1705 return -EOPNOTSUPP; 1706 1707 lock_sock(sk); 1708 1709 /* Callers should not provide a destination with stream sockets. */ 1710 if (msg->msg_namelen) { 1711 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1712 goto out; 1713 } 1714 1715 /* Send data only if both sides are not shutdown in the direction. */ 1716 if (sk->sk_shutdown & SEND_SHUTDOWN || 1717 vsk->peer_shutdown & RCV_SHUTDOWN) { 1718 err = -EPIPE; 1719 goto out; 1720 } 1721 1722 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1723 !vsock_addr_bound(&vsk->local_addr)) { 1724 err = -ENOTCONN; 1725 goto out; 1726 } 1727 1728 if (!vsock_addr_bound(&vsk->remote_addr)) { 1729 err = -EDESTADDRREQ; 1730 goto out; 1731 } 1732 1733 /* Wait for room in the produce queue to enqueue our user's data. */ 1734 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1735 1736 err = transport->notify_send_init(vsk, &send_data); 1737 if (err < 0) 1738 goto out; 1739 1740 while (total_written < len) { 1741 ssize_t written; 1742 1743 add_wait_queue(sk_sleep(sk), &wait); 1744 while (vsock_stream_has_space(vsk) == 0 && 1745 sk->sk_err == 0 && 1746 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1747 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1748 1749 /* Don't wait for non-blocking sockets. */ 1750 if (timeout == 0) { 1751 err = -EAGAIN; 1752 remove_wait_queue(sk_sleep(sk), &wait); 1753 goto out_err; 1754 } 1755 1756 err = transport->notify_send_pre_block(vsk, &send_data); 1757 if (err < 0) { 1758 remove_wait_queue(sk_sleep(sk), &wait); 1759 goto out_err; 1760 } 1761 1762 release_sock(sk); 1763 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1764 lock_sock(sk); 1765 if (signal_pending(current)) { 1766 err = sock_intr_errno(timeout); 1767 remove_wait_queue(sk_sleep(sk), &wait); 1768 goto out_err; 1769 } else if (timeout == 0) { 1770 err = -EAGAIN; 1771 remove_wait_queue(sk_sleep(sk), &wait); 1772 goto out_err; 1773 } 1774 } 1775 remove_wait_queue(sk_sleep(sk), &wait); 1776 1777 /* These checks occur both as part of and after the loop 1778 * conditional since we need to check before and after 1779 * sleeping. 1780 */ 1781 if (sk->sk_err) { 1782 err = -sk->sk_err; 1783 goto out_err; 1784 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1785 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1786 err = -EPIPE; 1787 goto out_err; 1788 } 1789 1790 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1791 if (err < 0) 1792 goto out_err; 1793 1794 /* Note that enqueue will only write as many bytes as are free 1795 * in the produce queue, so we don't need to ensure len is 1796 * smaller than the queue size. It is the caller's 1797 * responsibility to check how many bytes we were able to send. 1798 */ 1799 1800 written = transport->stream_enqueue( 1801 vsk, msg, 1802 len - total_written); 1803 if (written < 0) { 1804 err = -ENOMEM; 1805 goto out_err; 1806 } 1807 1808 total_written += written; 1809 1810 err = transport->notify_send_post_enqueue( 1811 vsk, written, &send_data); 1812 if (err < 0) 1813 goto out_err; 1814 1815 } 1816 1817 out_err: 1818 if (total_written > 0) 1819 err = total_written; 1820 out: 1821 release_sock(sk); 1822 return err; 1823 } 1824 1825 1826 static int 1827 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 1828 int flags) 1829 { 1830 struct sock *sk; 1831 struct vsock_sock *vsk; 1832 const struct vsock_transport *transport; 1833 int err; 1834 size_t target; 1835 ssize_t copied; 1836 long timeout; 1837 struct vsock_transport_recv_notify_data recv_data; 1838 1839 DEFINE_WAIT(wait); 1840 1841 sk = sock->sk; 1842 vsk = vsock_sk(sk); 1843 transport = vsk->transport; 1844 err = 0; 1845 1846 lock_sock(sk); 1847 1848 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 1849 /* Recvmsg is supposed to return 0 if a peer performs an 1850 * orderly shutdown. Differentiate between that case and when a 1851 * peer has not connected or a local shutdown occured with the 1852 * SOCK_DONE flag. 1853 */ 1854 if (sock_flag(sk, SOCK_DONE)) 1855 err = 0; 1856 else 1857 err = -ENOTCONN; 1858 1859 goto out; 1860 } 1861 1862 if (flags & MSG_OOB) { 1863 err = -EOPNOTSUPP; 1864 goto out; 1865 } 1866 1867 /* We don't check peer_shutdown flag here since peer may actually shut 1868 * down, but there can be data in the queue that a local socket can 1869 * receive. 1870 */ 1871 if (sk->sk_shutdown & RCV_SHUTDOWN) { 1872 err = 0; 1873 goto out; 1874 } 1875 1876 /* It is valid on Linux to pass in a zero-length receive buffer. This 1877 * is not an error. We may as well bail out now. 1878 */ 1879 if (!len) { 1880 err = 0; 1881 goto out; 1882 } 1883 1884 /* We must not copy less than target bytes into the user's buffer 1885 * before returning successfully, so we wait for the consume queue to 1886 * have that much data to consume before dequeueing. Note that this 1887 * makes it impossible to handle cases where target is greater than the 1888 * queue size. 1889 */ 1890 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1891 if (target >= transport->stream_rcvhiwat(vsk)) { 1892 err = -ENOMEM; 1893 goto out; 1894 } 1895 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1896 copied = 0; 1897 1898 err = transport->notify_recv_init(vsk, target, &recv_data); 1899 if (err < 0) 1900 goto out; 1901 1902 1903 while (1) { 1904 s64 ready; 1905 1906 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1907 ready = vsock_stream_has_data(vsk); 1908 1909 if (ready == 0) { 1910 if (sk->sk_err != 0 || 1911 (sk->sk_shutdown & RCV_SHUTDOWN) || 1912 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1913 finish_wait(sk_sleep(sk), &wait); 1914 break; 1915 } 1916 /* Don't wait for non-blocking sockets. */ 1917 if (timeout == 0) { 1918 err = -EAGAIN; 1919 finish_wait(sk_sleep(sk), &wait); 1920 break; 1921 } 1922 1923 err = transport->notify_recv_pre_block( 1924 vsk, target, &recv_data); 1925 if (err < 0) { 1926 finish_wait(sk_sleep(sk), &wait); 1927 break; 1928 } 1929 release_sock(sk); 1930 timeout = schedule_timeout(timeout); 1931 lock_sock(sk); 1932 1933 if (signal_pending(current)) { 1934 err = sock_intr_errno(timeout); 1935 finish_wait(sk_sleep(sk), &wait); 1936 break; 1937 } else if (timeout == 0) { 1938 err = -EAGAIN; 1939 finish_wait(sk_sleep(sk), &wait); 1940 break; 1941 } 1942 } else { 1943 ssize_t read; 1944 1945 finish_wait(sk_sleep(sk), &wait); 1946 1947 if (ready < 0) { 1948 /* Invalid queue pair content. XXX This should 1949 * be changed to a connection reset in a later 1950 * change. 1951 */ 1952 1953 err = -ENOMEM; 1954 goto out; 1955 } 1956 1957 err = transport->notify_recv_pre_dequeue( 1958 vsk, target, &recv_data); 1959 if (err < 0) 1960 break; 1961 1962 read = transport->stream_dequeue( 1963 vsk, msg, 1964 len - copied, flags); 1965 if (read < 0) { 1966 err = -ENOMEM; 1967 break; 1968 } 1969 1970 copied += read; 1971 1972 err = transport->notify_recv_post_dequeue( 1973 vsk, target, read, 1974 !(flags & MSG_PEEK), &recv_data); 1975 if (err < 0) 1976 goto out; 1977 1978 if (read >= target || flags & MSG_PEEK) 1979 break; 1980 1981 target -= read; 1982 } 1983 } 1984 1985 if (sk->sk_err) 1986 err = -sk->sk_err; 1987 else if (sk->sk_shutdown & RCV_SHUTDOWN) 1988 err = 0; 1989 1990 if (copied > 0) 1991 err = copied; 1992 1993 out: 1994 release_sock(sk); 1995 return err; 1996 } 1997 1998 static const struct proto_ops vsock_stream_ops = { 1999 .family = PF_VSOCK, 2000 .owner = THIS_MODULE, 2001 .release = vsock_release, 2002 .bind = vsock_bind, 2003 .connect = vsock_stream_connect, 2004 .socketpair = sock_no_socketpair, 2005 .accept = vsock_accept, 2006 .getname = vsock_getname, 2007 .poll = vsock_poll, 2008 .ioctl = sock_no_ioctl, 2009 .listen = vsock_listen, 2010 .shutdown = vsock_shutdown, 2011 .setsockopt = vsock_stream_setsockopt, 2012 .getsockopt = vsock_stream_getsockopt, 2013 .sendmsg = vsock_stream_sendmsg, 2014 .recvmsg = vsock_stream_recvmsg, 2015 .mmap = sock_no_mmap, 2016 .sendpage = sock_no_sendpage, 2017 }; 2018 2019 static int vsock_create(struct net *net, struct socket *sock, 2020 int protocol, int kern) 2021 { 2022 struct vsock_sock *vsk; 2023 struct sock *sk; 2024 int ret; 2025 2026 if (!sock) 2027 return -EINVAL; 2028 2029 if (protocol && protocol != PF_VSOCK) 2030 return -EPROTONOSUPPORT; 2031 2032 switch (sock->type) { 2033 case SOCK_DGRAM: 2034 sock->ops = &vsock_dgram_ops; 2035 break; 2036 case SOCK_STREAM: 2037 sock->ops = &vsock_stream_ops; 2038 break; 2039 default: 2040 return -ESOCKTNOSUPPORT; 2041 } 2042 2043 sock->state = SS_UNCONNECTED; 2044 2045 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2046 if (!sk) 2047 return -ENOMEM; 2048 2049 vsk = vsock_sk(sk); 2050 2051 if (sock->type == SOCK_DGRAM) { 2052 ret = vsock_assign_transport(vsk, NULL); 2053 if (ret < 0) { 2054 sock_put(sk); 2055 return ret; 2056 } 2057 } 2058 2059 vsock_insert_unbound(vsk); 2060 2061 return 0; 2062 } 2063 2064 static const struct net_proto_family vsock_family_ops = { 2065 .family = AF_VSOCK, 2066 .create = vsock_create, 2067 .owner = THIS_MODULE, 2068 }; 2069 2070 static long vsock_dev_do_ioctl(struct file *filp, 2071 unsigned int cmd, void __user *ptr) 2072 { 2073 u32 __user *p = ptr; 2074 u32 cid = VMADDR_CID_ANY; 2075 int retval = 0; 2076 2077 switch (cmd) { 2078 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2079 /* To be compatible with the VMCI behavior, we prioritize the 2080 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2081 */ 2082 if (transport_g2h) 2083 cid = transport_g2h->get_local_cid(); 2084 else if (transport_h2g) 2085 cid = transport_h2g->get_local_cid(); 2086 2087 if (put_user(cid, p) != 0) 2088 retval = -EFAULT; 2089 break; 2090 2091 default: 2092 retval = -ENOIOCTLCMD; 2093 } 2094 2095 return retval; 2096 } 2097 2098 static long vsock_dev_ioctl(struct file *filp, 2099 unsigned int cmd, unsigned long arg) 2100 { 2101 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2102 } 2103 2104 #ifdef CONFIG_COMPAT 2105 static long vsock_dev_compat_ioctl(struct file *filp, 2106 unsigned int cmd, unsigned long arg) 2107 { 2108 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2109 } 2110 #endif 2111 2112 static const struct file_operations vsock_device_ops = { 2113 .owner = THIS_MODULE, 2114 .unlocked_ioctl = vsock_dev_ioctl, 2115 #ifdef CONFIG_COMPAT 2116 .compat_ioctl = vsock_dev_compat_ioctl, 2117 #endif 2118 .open = nonseekable_open, 2119 }; 2120 2121 static struct miscdevice vsock_device = { 2122 .name = "vsock", 2123 .fops = &vsock_device_ops, 2124 }; 2125 2126 static int __init vsock_init(void) 2127 { 2128 int err = 0; 2129 2130 vsock_init_tables(); 2131 2132 vsock_proto.owner = THIS_MODULE; 2133 vsock_device.minor = MISC_DYNAMIC_MINOR; 2134 err = misc_register(&vsock_device); 2135 if (err) { 2136 pr_err("Failed to register misc device\n"); 2137 goto err_reset_transport; 2138 } 2139 2140 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2141 if (err) { 2142 pr_err("Cannot register vsock protocol\n"); 2143 goto err_deregister_misc; 2144 } 2145 2146 err = sock_register(&vsock_family_ops); 2147 if (err) { 2148 pr_err("could not register af_vsock (%d) address family: %d\n", 2149 AF_VSOCK, err); 2150 goto err_unregister_proto; 2151 } 2152 2153 return 0; 2154 2155 err_unregister_proto: 2156 proto_unregister(&vsock_proto); 2157 err_deregister_misc: 2158 misc_deregister(&vsock_device); 2159 err_reset_transport: 2160 return err; 2161 } 2162 2163 static void __exit vsock_exit(void) 2164 { 2165 misc_deregister(&vsock_device); 2166 sock_unregister(AF_VSOCK); 2167 proto_unregister(&vsock_proto); 2168 } 2169 2170 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2171 { 2172 return vsk->transport; 2173 } 2174 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2175 2176 int vsock_core_register(const struct vsock_transport *t, int features) 2177 { 2178 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2179 int err = mutex_lock_interruptible(&vsock_register_mutex); 2180 2181 if (err) 2182 return err; 2183 2184 t_h2g = transport_h2g; 2185 t_g2h = transport_g2h; 2186 t_dgram = transport_dgram; 2187 t_local = transport_local; 2188 2189 if (features & VSOCK_TRANSPORT_F_H2G) { 2190 if (t_h2g) { 2191 err = -EBUSY; 2192 goto err_busy; 2193 } 2194 t_h2g = t; 2195 } 2196 2197 if (features & VSOCK_TRANSPORT_F_G2H) { 2198 if (t_g2h) { 2199 err = -EBUSY; 2200 goto err_busy; 2201 } 2202 t_g2h = t; 2203 } 2204 2205 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2206 if (t_dgram) { 2207 err = -EBUSY; 2208 goto err_busy; 2209 } 2210 t_dgram = t; 2211 } 2212 2213 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2214 if (t_local) { 2215 err = -EBUSY; 2216 goto err_busy; 2217 } 2218 t_local = t; 2219 } 2220 2221 transport_h2g = t_h2g; 2222 transport_g2h = t_g2h; 2223 transport_dgram = t_dgram; 2224 transport_local = t_local; 2225 2226 err_busy: 2227 mutex_unlock(&vsock_register_mutex); 2228 return err; 2229 } 2230 EXPORT_SYMBOL_GPL(vsock_core_register); 2231 2232 void vsock_core_unregister(const struct vsock_transport *t) 2233 { 2234 mutex_lock(&vsock_register_mutex); 2235 2236 if (transport_h2g == t) 2237 transport_h2g = NULL; 2238 2239 if (transport_g2h == t) 2240 transport_g2h = NULL; 2241 2242 if (transport_dgram == t) 2243 transport_dgram = NULL; 2244 2245 if (transport_local == t) 2246 transport_local = NULL; 2247 2248 mutex_unlock(&vsock_register_mutex); 2249 } 2250 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2251 2252 module_init(vsock_init); 2253 module_exit(vsock_exit); 2254 2255 MODULE_AUTHOR("VMware, Inc."); 2256 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2257 MODULE_VERSION("1.0.2.0-k"); 2258 MODULE_LICENSE("GPL v2"); 2259