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