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