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/compat.h> 89 #include <linux/types.h> 90 #include <linux/bitops.h> 91 #include <linux/cred.h> 92 #include <linux/init.h> 93 #include <linux/io.h> 94 #include <linux/kernel.h> 95 #include <linux/sched/signal.h> 96 #include <linux/kmod.h> 97 #include <linux/list.h> 98 #include <linux/miscdevice.h> 99 #include <linux/module.h> 100 #include <linux/mutex.h> 101 #include <linux/net.h> 102 #include <linux/poll.h> 103 #include <linux/random.h> 104 #include <linux/skbuff.h> 105 #include <linux/smp.h> 106 #include <linux/socket.h> 107 #include <linux/stddef.h> 108 #include <linux/unistd.h> 109 #include <linux/wait.h> 110 #include <linux/workqueue.h> 111 #include <net/sock.h> 112 #include <net/af_vsock.h> 113 114 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr); 115 static void vsock_sk_destruct(struct sock *sk); 116 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 117 118 /* Protocol family. */ 119 static struct proto vsock_proto = { 120 .name = "AF_VSOCK", 121 .owner = THIS_MODULE, 122 .obj_size = sizeof(struct vsock_sock), 123 }; 124 125 /* The default peer timeout indicates how long we will wait for a peer response 126 * to a control message. 127 */ 128 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ) 129 130 #define VSOCK_DEFAULT_BUFFER_SIZE (1024 * 256) 131 #define VSOCK_DEFAULT_BUFFER_MAX_SIZE (1024 * 256) 132 #define VSOCK_DEFAULT_BUFFER_MIN_SIZE 128 133 134 /* Transport used for host->guest communication */ 135 static const struct vsock_transport *transport_h2g; 136 /* Transport used for guest->host communication */ 137 static const struct vsock_transport *transport_g2h; 138 /* Transport used for DGRAM communication */ 139 static const struct vsock_transport *transport_dgram; 140 /* Transport used for local communication */ 141 static const struct vsock_transport *transport_local; 142 static DEFINE_MUTEX(vsock_register_mutex); 143 144 /**** UTILS ****/ 145 146 /* Each bound VSocket is stored in the bind hash table and each connected 147 * VSocket is stored in the connected hash table. 148 * 149 * Unbound sockets are all put on the same list attached to the end of the hash 150 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in 151 * the bucket that their local address hashes to (vsock_bound_sockets(addr) 152 * represents the list that addr hashes to). 153 * 154 * Specifically, we initialize the vsock_bind_table array to a size of 155 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through 156 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and 157 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function 158 * mods with VSOCK_HASH_SIZE to ensure this. 159 */ 160 #define MAX_PORT_RETRIES 24 161 162 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE) 163 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)]) 164 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE]) 165 166 /* XXX This can probably be implemented in a better way. */ 167 #define VSOCK_CONN_HASH(src, dst) \ 168 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE) 169 #define vsock_connected_sockets(src, dst) \ 170 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)]) 171 #define vsock_connected_sockets_vsk(vsk) \ 172 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr) 173 174 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 175 EXPORT_SYMBOL_GPL(vsock_bind_table); 176 struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 177 EXPORT_SYMBOL_GPL(vsock_connected_table); 178 DEFINE_SPINLOCK(vsock_table_lock); 179 EXPORT_SYMBOL_GPL(vsock_table_lock); 180 181 /* Autobind this socket to the local address if necessary. */ 182 static int vsock_auto_bind(struct vsock_sock *vsk) 183 { 184 struct sock *sk = sk_vsock(vsk); 185 struct sockaddr_vm local_addr; 186 187 if (vsock_addr_bound(&vsk->local_addr)) 188 return 0; 189 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 190 return __vsock_bind(sk, &local_addr); 191 } 192 193 static void vsock_init_tables(void) 194 { 195 int i; 196 197 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++) 198 INIT_LIST_HEAD(&vsock_bind_table[i]); 199 200 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) 201 INIT_LIST_HEAD(&vsock_connected_table[i]); 202 } 203 204 static void __vsock_insert_bound(struct list_head *list, 205 struct vsock_sock *vsk) 206 { 207 sock_hold(&vsk->sk); 208 list_add(&vsk->bound_table, list); 209 } 210 211 static void __vsock_insert_connected(struct list_head *list, 212 struct vsock_sock *vsk) 213 { 214 sock_hold(&vsk->sk); 215 list_add(&vsk->connected_table, list); 216 } 217 218 static void __vsock_remove_bound(struct vsock_sock *vsk) 219 { 220 list_del_init(&vsk->bound_table); 221 sock_put(&vsk->sk); 222 } 223 224 static void __vsock_remove_connected(struct vsock_sock *vsk) 225 { 226 list_del_init(&vsk->connected_table); 227 sock_put(&vsk->sk); 228 } 229 230 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr) 231 { 232 struct vsock_sock *vsk; 233 234 list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) { 235 if (vsock_addr_equals_addr(addr, &vsk->local_addr)) 236 return sk_vsock(vsk); 237 238 if (addr->svm_port == vsk->local_addr.svm_port && 239 (vsk->local_addr.svm_cid == VMADDR_CID_ANY || 240 addr->svm_cid == VMADDR_CID_ANY)) 241 return sk_vsock(vsk); 242 } 243 244 return NULL; 245 } 246 247 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src, 248 struct sockaddr_vm *dst) 249 { 250 struct vsock_sock *vsk; 251 252 list_for_each_entry(vsk, vsock_connected_sockets(src, dst), 253 connected_table) { 254 if (vsock_addr_equals_addr(src, &vsk->remote_addr) && 255 dst->svm_port == vsk->local_addr.svm_port) { 256 return sk_vsock(vsk); 257 } 258 } 259 260 return NULL; 261 } 262 263 static void vsock_insert_unbound(struct vsock_sock *vsk) 264 { 265 spin_lock_bh(&vsock_table_lock); 266 __vsock_insert_bound(vsock_unbound_sockets, vsk); 267 spin_unlock_bh(&vsock_table_lock); 268 } 269 270 void vsock_insert_connected(struct vsock_sock *vsk) 271 { 272 struct list_head *list = vsock_connected_sockets( 273 &vsk->remote_addr, &vsk->local_addr); 274 275 spin_lock_bh(&vsock_table_lock); 276 __vsock_insert_connected(list, vsk); 277 spin_unlock_bh(&vsock_table_lock); 278 } 279 EXPORT_SYMBOL_GPL(vsock_insert_connected); 280 281 void vsock_remove_bound(struct vsock_sock *vsk) 282 { 283 spin_lock_bh(&vsock_table_lock); 284 if (__vsock_in_bound_table(vsk)) 285 __vsock_remove_bound(vsk); 286 spin_unlock_bh(&vsock_table_lock); 287 } 288 EXPORT_SYMBOL_GPL(vsock_remove_bound); 289 290 void vsock_remove_connected(struct vsock_sock *vsk) 291 { 292 spin_lock_bh(&vsock_table_lock); 293 if (__vsock_in_connected_table(vsk)) 294 __vsock_remove_connected(vsk); 295 spin_unlock_bh(&vsock_table_lock); 296 } 297 EXPORT_SYMBOL_GPL(vsock_remove_connected); 298 299 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr) 300 { 301 struct sock *sk; 302 303 spin_lock_bh(&vsock_table_lock); 304 sk = __vsock_find_bound_socket(addr); 305 if (sk) 306 sock_hold(sk); 307 308 spin_unlock_bh(&vsock_table_lock); 309 310 return sk; 311 } 312 EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 313 314 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, 315 struct sockaddr_vm *dst) 316 { 317 struct sock *sk; 318 319 spin_lock_bh(&vsock_table_lock); 320 sk = __vsock_find_connected_socket(src, dst); 321 if (sk) 322 sock_hold(sk); 323 324 spin_unlock_bh(&vsock_table_lock); 325 326 return sk; 327 } 328 EXPORT_SYMBOL_GPL(vsock_find_connected_socket); 329 330 void vsock_remove_sock(struct vsock_sock *vsk) 331 { 332 vsock_remove_bound(vsk); 333 vsock_remove_connected(vsk); 334 } 335 EXPORT_SYMBOL_GPL(vsock_remove_sock); 336 337 void vsock_for_each_connected_socket(struct vsock_transport *transport, 338 void (*fn)(struct sock *sk)) 339 { 340 int i; 341 342 spin_lock_bh(&vsock_table_lock); 343 344 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) { 345 struct vsock_sock *vsk; 346 list_for_each_entry(vsk, &vsock_connected_table[i], 347 connected_table) { 348 if (vsk->transport != transport) 349 continue; 350 351 fn(sk_vsock(vsk)); 352 } 353 } 354 355 spin_unlock_bh(&vsock_table_lock); 356 } 357 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket); 358 359 void vsock_add_pending(struct sock *listener, struct sock *pending) 360 { 361 struct vsock_sock *vlistener; 362 struct vsock_sock *vpending; 363 364 vlistener = vsock_sk(listener); 365 vpending = vsock_sk(pending); 366 367 sock_hold(pending); 368 sock_hold(listener); 369 list_add_tail(&vpending->pending_links, &vlistener->pending_links); 370 } 371 EXPORT_SYMBOL_GPL(vsock_add_pending); 372 373 void vsock_remove_pending(struct sock *listener, struct sock *pending) 374 { 375 struct vsock_sock *vpending = vsock_sk(pending); 376 377 list_del_init(&vpending->pending_links); 378 sock_put(listener); 379 sock_put(pending); 380 } 381 EXPORT_SYMBOL_GPL(vsock_remove_pending); 382 383 void vsock_enqueue_accept(struct sock *listener, struct sock *connected) 384 { 385 struct vsock_sock *vlistener; 386 struct vsock_sock *vconnected; 387 388 vlistener = vsock_sk(listener); 389 vconnected = vsock_sk(connected); 390 391 sock_hold(connected); 392 sock_hold(listener); 393 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue); 394 } 395 EXPORT_SYMBOL_GPL(vsock_enqueue_accept); 396 397 static bool vsock_use_local_transport(unsigned int remote_cid) 398 { 399 if (!transport_local) 400 return false; 401 402 if (remote_cid == VMADDR_CID_LOCAL) 403 return true; 404 405 if (transport_g2h) { 406 return remote_cid == transport_g2h->get_local_cid(); 407 } else { 408 return remote_cid == VMADDR_CID_HOST; 409 } 410 } 411 412 static void vsock_deassign_transport(struct vsock_sock *vsk) 413 { 414 if (!vsk->transport) 415 return; 416 417 vsk->transport->destruct(vsk); 418 module_put(vsk->transport->module); 419 vsk->transport = NULL; 420 } 421 422 /* Assign a transport to a socket and call the .init transport callback. 423 * 424 * Note: for connection oriented socket this must be called when vsk->remote_addr 425 * is set (e.g. during the connect() or when a connection request on a listener 426 * socket is received). 427 * The vsk->remote_addr is used to decide which transport to use: 428 * - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if 429 * g2h is not loaded, will use local transport; 430 * - remote CID <= VMADDR_CID_HOST or h2g is not loaded or remote flags field 431 * includes VMADDR_FLAG_TO_HOST flag value, will use guest->host transport; 432 * - remote CID > VMADDR_CID_HOST will use host->guest transport; 433 */ 434 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk) 435 { 436 const struct vsock_transport *new_transport; 437 struct sock *sk = sk_vsock(vsk); 438 unsigned int remote_cid = vsk->remote_addr.svm_cid; 439 __u8 remote_flags; 440 int ret; 441 442 /* If the packet is coming with the source and destination CIDs higher 443 * than VMADDR_CID_HOST, then a vsock channel where all the packets are 444 * forwarded to the host should be established. Then the host will 445 * need to forward the packets to the guest. 446 * 447 * The flag is set on the (listen) receive path (psk is not NULL). On 448 * the connect path the flag can be set by the user space application. 449 */ 450 if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST && 451 vsk->remote_addr.svm_cid > VMADDR_CID_HOST) 452 vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST; 453 454 remote_flags = vsk->remote_addr.svm_flags; 455 456 switch (sk->sk_type) { 457 case SOCK_DGRAM: 458 new_transport = transport_dgram; 459 break; 460 case SOCK_STREAM: 461 case SOCK_SEQPACKET: 462 if (vsock_use_local_transport(remote_cid)) 463 new_transport = transport_local; 464 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g || 465 (remote_flags & VMADDR_FLAG_TO_HOST)) 466 new_transport = transport_g2h; 467 else 468 new_transport = transport_h2g; 469 break; 470 default: 471 return -ESOCKTNOSUPPORT; 472 } 473 474 if (vsk->transport) { 475 if (vsk->transport == new_transport) 476 return 0; 477 478 /* transport->release() must be called with sock lock acquired. 479 * This path can only be taken during vsock_connect(), where we 480 * have already held the sock lock. In the other cases, this 481 * function is called on a new socket which is not assigned to 482 * any transport. 483 */ 484 vsk->transport->release(vsk); 485 vsock_deassign_transport(vsk); 486 } 487 488 /* We increase the module refcnt to prevent the transport unloading 489 * while there are open sockets assigned to it. 490 */ 491 if (!new_transport || !try_module_get(new_transport->module)) 492 return -ENODEV; 493 494 if (sk->sk_type == SOCK_SEQPACKET) { 495 if (!new_transport->seqpacket_allow || 496 !new_transport->seqpacket_allow(remote_cid)) { 497 module_put(new_transport->module); 498 return -ESOCKTNOSUPPORT; 499 } 500 } 501 502 ret = new_transport->init(vsk, psk); 503 if (ret) { 504 module_put(new_transport->module); 505 return ret; 506 } 507 508 vsk->transport = new_transport; 509 510 return 0; 511 } 512 EXPORT_SYMBOL_GPL(vsock_assign_transport); 513 514 bool vsock_find_cid(unsigned int cid) 515 { 516 if (transport_g2h && cid == transport_g2h->get_local_cid()) 517 return true; 518 519 if (transport_h2g && cid == VMADDR_CID_HOST) 520 return true; 521 522 if (transport_local && cid == VMADDR_CID_LOCAL) 523 return true; 524 525 return false; 526 } 527 EXPORT_SYMBOL_GPL(vsock_find_cid); 528 529 static struct sock *vsock_dequeue_accept(struct sock *listener) 530 { 531 struct vsock_sock *vlistener; 532 struct vsock_sock *vconnected; 533 534 vlistener = vsock_sk(listener); 535 536 if (list_empty(&vlistener->accept_queue)) 537 return NULL; 538 539 vconnected = list_entry(vlistener->accept_queue.next, 540 struct vsock_sock, accept_queue); 541 542 list_del_init(&vconnected->accept_queue); 543 sock_put(listener); 544 /* The caller will need a reference on the connected socket so we let 545 * it call sock_put(). 546 */ 547 548 return sk_vsock(vconnected); 549 } 550 551 static bool vsock_is_accept_queue_empty(struct sock *sk) 552 { 553 struct vsock_sock *vsk = vsock_sk(sk); 554 return list_empty(&vsk->accept_queue); 555 } 556 557 static bool vsock_is_pending(struct sock *sk) 558 { 559 struct vsock_sock *vsk = vsock_sk(sk); 560 return !list_empty(&vsk->pending_links); 561 } 562 563 static int vsock_send_shutdown(struct sock *sk, int mode) 564 { 565 struct vsock_sock *vsk = vsock_sk(sk); 566 567 if (!vsk->transport) 568 return -ENODEV; 569 570 return vsk->transport->shutdown(vsk, mode); 571 } 572 573 static void vsock_pending_work(struct work_struct *work) 574 { 575 struct sock *sk; 576 struct sock *listener; 577 struct vsock_sock *vsk; 578 bool cleanup; 579 580 vsk = container_of(work, struct vsock_sock, pending_work.work); 581 sk = sk_vsock(vsk); 582 listener = vsk->listener; 583 cleanup = true; 584 585 lock_sock(listener); 586 lock_sock_nested(sk, SINGLE_DEPTH_NESTING); 587 588 if (vsock_is_pending(sk)) { 589 vsock_remove_pending(listener, sk); 590 591 sk_acceptq_removed(listener); 592 } else if (!vsk->rejected) { 593 /* We are not on the pending list and accept() did not reject 594 * us, so we must have been accepted by our user process. We 595 * just need to drop our references to the sockets and be on 596 * our way. 597 */ 598 cleanup = false; 599 goto out; 600 } 601 602 /* We need to remove ourself from the global connected sockets list so 603 * incoming packets can't find this socket, and to reduce the reference 604 * count. 605 */ 606 vsock_remove_connected(vsk); 607 608 sk->sk_state = TCP_CLOSE; 609 610 out: 611 release_sock(sk); 612 release_sock(listener); 613 if (cleanup) 614 sock_put(sk); 615 616 sock_put(sk); 617 sock_put(listener); 618 } 619 620 /**** SOCKET OPERATIONS ****/ 621 622 static int __vsock_bind_connectible(struct vsock_sock *vsk, 623 struct sockaddr_vm *addr) 624 { 625 static u32 port; 626 struct sockaddr_vm new_addr; 627 628 if (!port) 629 port = get_random_u32_above(LAST_RESERVED_PORT); 630 631 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 632 633 if (addr->svm_port == VMADDR_PORT_ANY) { 634 bool found = false; 635 unsigned int i; 636 637 for (i = 0; i < MAX_PORT_RETRIES; i++) { 638 if (port <= LAST_RESERVED_PORT) 639 port = LAST_RESERVED_PORT + 1; 640 641 new_addr.svm_port = port++; 642 643 if (!__vsock_find_bound_socket(&new_addr)) { 644 found = true; 645 break; 646 } 647 } 648 649 if (!found) 650 return -EADDRNOTAVAIL; 651 } else { 652 /* If port is in reserved range, ensure caller 653 * has necessary privileges. 654 */ 655 if (addr->svm_port <= LAST_RESERVED_PORT && 656 !capable(CAP_NET_BIND_SERVICE)) { 657 return -EACCES; 658 } 659 660 if (__vsock_find_bound_socket(&new_addr)) 661 return -EADDRINUSE; 662 } 663 664 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 665 666 /* Remove connection oriented sockets from the unbound list and add them 667 * to the hash table for easy lookup by its address. The unbound list 668 * is simply an extra entry at the end of the hash table, a trick used 669 * by AF_UNIX. 670 */ 671 __vsock_remove_bound(vsk); 672 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 673 674 return 0; 675 } 676 677 static int __vsock_bind_dgram(struct vsock_sock *vsk, 678 struct sockaddr_vm *addr) 679 { 680 return vsk->transport->dgram_bind(vsk, addr); 681 } 682 683 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 684 { 685 struct vsock_sock *vsk = vsock_sk(sk); 686 int retval; 687 688 /* First ensure this socket isn't already bound. */ 689 if (vsock_addr_bound(&vsk->local_addr)) 690 return -EINVAL; 691 692 /* Now bind to the provided address or select appropriate values if 693 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 694 * like AF_INET prevents binding to a non-local IP address (in most 695 * cases), we only allow binding to a local CID. 696 */ 697 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid)) 698 return -EADDRNOTAVAIL; 699 700 switch (sk->sk_socket->type) { 701 case SOCK_STREAM: 702 case SOCK_SEQPACKET: 703 spin_lock_bh(&vsock_table_lock); 704 retval = __vsock_bind_connectible(vsk, addr); 705 spin_unlock_bh(&vsock_table_lock); 706 break; 707 708 case SOCK_DGRAM: 709 retval = __vsock_bind_dgram(vsk, addr); 710 break; 711 712 default: 713 retval = -EINVAL; 714 break; 715 } 716 717 return retval; 718 } 719 720 static void vsock_connect_timeout(struct work_struct *work); 721 722 static struct sock *__vsock_create(struct net *net, 723 struct socket *sock, 724 struct sock *parent, 725 gfp_t priority, 726 unsigned short type, 727 int kern) 728 { 729 struct sock *sk; 730 struct vsock_sock *psk; 731 struct vsock_sock *vsk; 732 733 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 734 if (!sk) 735 return NULL; 736 737 sock_init_data(sock, sk); 738 739 /* sk->sk_type is normally set in sock_init_data, but only if sock is 740 * non-NULL. We make sure that our sockets always have a type by 741 * setting it here if needed. 742 */ 743 if (!sock) 744 sk->sk_type = type; 745 746 vsk = vsock_sk(sk); 747 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 748 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 749 750 sk->sk_destruct = vsock_sk_destruct; 751 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 752 sock_reset_flag(sk, SOCK_DONE); 753 754 INIT_LIST_HEAD(&vsk->bound_table); 755 INIT_LIST_HEAD(&vsk->connected_table); 756 vsk->listener = NULL; 757 INIT_LIST_HEAD(&vsk->pending_links); 758 INIT_LIST_HEAD(&vsk->accept_queue); 759 vsk->rejected = false; 760 vsk->sent_request = false; 761 vsk->ignore_connecting_rst = false; 762 vsk->peer_shutdown = 0; 763 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 764 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 765 766 psk = parent ? vsock_sk(parent) : NULL; 767 if (parent) { 768 vsk->trusted = psk->trusted; 769 vsk->owner = get_cred(psk->owner); 770 vsk->connect_timeout = psk->connect_timeout; 771 vsk->buffer_size = psk->buffer_size; 772 vsk->buffer_min_size = psk->buffer_min_size; 773 vsk->buffer_max_size = psk->buffer_max_size; 774 security_sk_clone(parent, sk); 775 } else { 776 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN); 777 vsk->owner = get_current_cred(); 778 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 779 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE; 780 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE; 781 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE; 782 } 783 784 return sk; 785 } 786 787 static bool sock_type_connectible(u16 type) 788 { 789 return (type == SOCK_STREAM) || (type == SOCK_SEQPACKET); 790 } 791 792 static void __vsock_release(struct sock *sk, int level) 793 { 794 if (sk) { 795 struct sock *pending; 796 struct vsock_sock *vsk; 797 798 vsk = vsock_sk(sk); 799 pending = NULL; /* Compiler warning. */ 800 801 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 802 * version to avoid the warning "possible recursive locking 803 * detected". When "level" is 0, lock_sock_nested(sk, level) 804 * is the same as lock_sock(sk). 805 */ 806 lock_sock_nested(sk, level); 807 808 if (vsk->transport) 809 vsk->transport->release(vsk); 810 else if (sock_type_connectible(sk->sk_type)) 811 vsock_remove_sock(vsk); 812 813 sock_orphan(sk); 814 sk->sk_shutdown = SHUTDOWN_MASK; 815 816 skb_queue_purge(&sk->sk_receive_queue); 817 818 /* Clean up any sockets that never were accepted. */ 819 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 820 __vsock_release(pending, SINGLE_DEPTH_NESTING); 821 sock_put(pending); 822 } 823 824 release_sock(sk); 825 sock_put(sk); 826 } 827 } 828 829 static void vsock_sk_destruct(struct sock *sk) 830 { 831 struct vsock_sock *vsk = vsock_sk(sk); 832 833 vsock_deassign_transport(vsk); 834 835 /* When clearing these addresses, there's no need to set the family and 836 * possibly register the address family with the kernel. 837 */ 838 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 839 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 840 841 put_cred(vsk->owner); 842 } 843 844 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 845 { 846 int err; 847 848 err = sock_queue_rcv_skb(sk, skb); 849 if (err) 850 kfree_skb(skb); 851 852 return err; 853 } 854 855 struct sock *vsock_create_connected(struct sock *parent) 856 { 857 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL, 858 parent->sk_type, 0); 859 } 860 EXPORT_SYMBOL_GPL(vsock_create_connected); 861 862 s64 vsock_stream_has_data(struct vsock_sock *vsk) 863 { 864 return vsk->transport->stream_has_data(vsk); 865 } 866 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 867 868 static s64 vsock_connectible_has_data(struct vsock_sock *vsk) 869 { 870 struct sock *sk = sk_vsock(vsk); 871 872 if (sk->sk_type == SOCK_SEQPACKET) 873 return vsk->transport->seqpacket_has_data(vsk); 874 else 875 return vsock_stream_has_data(vsk); 876 } 877 878 s64 vsock_stream_has_space(struct vsock_sock *vsk) 879 { 880 return vsk->transport->stream_has_space(vsk); 881 } 882 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 883 884 void vsock_data_ready(struct sock *sk) 885 { 886 struct vsock_sock *vsk = vsock_sk(sk); 887 888 if (vsock_stream_has_data(vsk) >= sk->sk_rcvlowat || 889 sock_flag(sk, SOCK_DONE)) 890 sk->sk_data_ready(sk); 891 } 892 EXPORT_SYMBOL_GPL(vsock_data_ready); 893 894 static int vsock_release(struct socket *sock) 895 { 896 __vsock_release(sock->sk, 0); 897 sock->sk = NULL; 898 sock->state = SS_FREE; 899 900 return 0; 901 } 902 903 static int 904 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 905 { 906 int err; 907 struct sock *sk; 908 struct sockaddr_vm *vm_addr; 909 910 sk = sock->sk; 911 912 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 913 return -EINVAL; 914 915 lock_sock(sk); 916 err = __vsock_bind(sk, vm_addr); 917 release_sock(sk); 918 919 return err; 920 } 921 922 static int vsock_getname(struct socket *sock, 923 struct sockaddr *addr, int peer) 924 { 925 int err; 926 struct sock *sk; 927 struct vsock_sock *vsk; 928 struct sockaddr_vm *vm_addr; 929 930 sk = sock->sk; 931 vsk = vsock_sk(sk); 932 err = 0; 933 934 lock_sock(sk); 935 936 if (peer) { 937 if (sock->state != SS_CONNECTED) { 938 err = -ENOTCONN; 939 goto out; 940 } 941 vm_addr = &vsk->remote_addr; 942 } else { 943 vm_addr = &vsk->local_addr; 944 } 945 946 if (!vm_addr) { 947 err = -EINVAL; 948 goto out; 949 } 950 951 /* sys_getsockname() and sys_getpeername() pass us a 952 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 953 * that macro is defined in socket.c instead of .h, so we hardcode its 954 * value here. 955 */ 956 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 957 memcpy(addr, vm_addr, sizeof(*vm_addr)); 958 err = sizeof(*vm_addr); 959 960 out: 961 release_sock(sk); 962 return err; 963 } 964 965 static int vsock_shutdown(struct socket *sock, int mode) 966 { 967 int err; 968 struct sock *sk; 969 970 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 971 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 972 * here like the other address families do. Note also that the 973 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 974 * which is what we want. 975 */ 976 mode++; 977 978 if ((mode & ~SHUTDOWN_MASK) || !mode) 979 return -EINVAL; 980 981 /* If this is a connection oriented socket and it is not connected then 982 * bail out immediately. If it is a DGRAM socket then we must first 983 * kick the socket so that it wakes up from any sleeping calls, for 984 * example recv(), and then afterwards return the error. 985 */ 986 987 sk = sock->sk; 988 989 lock_sock(sk); 990 if (sock->state == SS_UNCONNECTED) { 991 err = -ENOTCONN; 992 if (sock_type_connectible(sk->sk_type)) 993 goto out; 994 } else { 995 sock->state = SS_DISCONNECTING; 996 err = 0; 997 } 998 999 /* Receive and send shutdowns are treated alike. */ 1000 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 1001 if (mode) { 1002 sk->sk_shutdown |= mode; 1003 sk->sk_state_change(sk); 1004 1005 if (sock_type_connectible(sk->sk_type)) { 1006 sock_reset_flag(sk, SOCK_DONE); 1007 vsock_send_shutdown(sk, mode); 1008 } 1009 } 1010 1011 out: 1012 release_sock(sk); 1013 return err; 1014 } 1015 1016 static __poll_t vsock_poll(struct file *file, struct socket *sock, 1017 poll_table *wait) 1018 { 1019 struct sock *sk; 1020 __poll_t mask; 1021 struct vsock_sock *vsk; 1022 1023 sk = sock->sk; 1024 vsk = vsock_sk(sk); 1025 1026 poll_wait(file, sk_sleep(sk), wait); 1027 mask = 0; 1028 1029 if (sk->sk_err) 1030 /* Signify that there has been an error on this socket. */ 1031 mask |= EPOLLERR; 1032 1033 /* INET sockets treat local write shutdown and peer write shutdown as a 1034 * case of EPOLLHUP set. 1035 */ 1036 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 1037 ((sk->sk_shutdown & SEND_SHUTDOWN) && 1038 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 1039 mask |= EPOLLHUP; 1040 } 1041 1042 if (sk->sk_shutdown & RCV_SHUTDOWN || 1043 vsk->peer_shutdown & SEND_SHUTDOWN) { 1044 mask |= EPOLLRDHUP; 1045 } 1046 1047 if (sock->type == SOCK_DGRAM) { 1048 /* For datagram sockets we can read if there is something in 1049 * the queue and write as long as the socket isn't shutdown for 1050 * sending. 1051 */ 1052 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 1053 (sk->sk_shutdown & RCV_SHUTDOWN)) { 1054 mask |= EPOLLIN | EPOLLRDNORM; 1055 } 1056 1057 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1058 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 1059 1060 } else if (sock_type_connectible(sk->sk_type)) { 1061 const struct vsock_transport *transport; 1062 1063 lock_sock(sk); 1064 1065 transport = vsk->transport; 1066 1067 /* Listening sockets that have connections in their accept 1068 * queue can be read. 1069 */ 1070 if (sk->sk_state == TCP_LISTEN 1071 && !vsock_is_accept_queue_empty(sk)) 1072 mask |= EPOLLIN | EPOLLRDNORM; 1073 1074 /* If there is something in the queue then we can read. */ 1075 if (transport && transport->stream_is_active(vsk) && 1076 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1077 bool data_ready_now = false; 1078 int target = sock_rcvlowat(sk, 0, INT_MAX); 1079 int ret = transport->notify_poll_in( 1080 vsk, target, &data_ready_now); 1081 if (ret < 0) { 1082 mask |= EPOLLERR; 1083 } else { 1084 if (data_ready_now) 1085 mask |= EPOLLIN | EPOLLRDNORM; 1086 1087 } 1088 } 1089 1090 /* Sockets whose connections have been closed, reset, or 1091 * terminated should also be considered read, and we check the 1092 * shutdown flag for that. 1093 */ 1094 if (sk->sk_shutdown & RCV_SHUTDOWN || 1095 vsk->peer_shutdown & SEND_SHUTDOWN) { 1096 mask |= EPOLLIN | EPOLLRDNORM; 1097 } 1098 1099 /* Connected sockets that can produce data can be written. */ 1100 if (transport && sk->sk_state == TCP_ESTABLISHED) { 1101 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1102 bool space_avail_now = false; 1103 int ret = transport->notify_poll_out( 1104 vsk, 1, &space_avail_now); 1105 if (ret < 0) { 1106 mask |= EPOLLERR; 1107 } else { 1108 if (space_avail_now) 1109 /* Remove EPOLLWRBAND since INET 1110 * sockets are not setting it. 1111 */ 1112 mask |= EPOLLOUT | EPOLLWRNORM; 1113 1114 } 1115 } 1116 } 1117 1118 /* Simulate INET socket poll behaviors, which sets 1119 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 1120 * but local send is not shutdown. 1121 */ 1122 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 1123 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1124 mask |= EPOLLOUT | EPOLLWRNORM; 1125 1126 } 1127 1128 release_sock(sk); 1129 } 1130 1131 return mask; 1132 } 1133 1134 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 1135 size_t len) 1136 { 1137 int err; 1138 struct sock *sk; 1139 struct vsock_sock *vsk; 1140 struct sockaddr_vm *remote_addr; 1141 const struct vsock_transport *transport; 1142 1143 if (msg->msg_flags & MSG_OOB) 1144 return -EOPNOTSUPP; 1145 1146 /* For now, MSG_DONTWAIT is always assumed... */ 1147 err = 0; 1148 sk = sock->sk; 1149 vsk = vsock_sk(sk); 1150 1151 lock_sock(sk); 1152 1153 transport = vsk->transport; 1154 1155 err = vsock_auto_bind(vsk); 1156 if (err) 1157 goto out; 1158 1159 1160 /* If the provided message contains an address, use that. Otherwise 1161 * fall back on the socket's remote handle (if it has been connected). 1162 */ 1163 if (msg->msg_name && 1164 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 1165 &remote_addr) == 0) { 1166 /* Ensure this address is of the right type and is a valid 1167 * destination. 1168 */ 1169 1170 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1171 remote_addr->svm_cid = transport->get_local_cid(); 1172 1173 if (!vsock_addr_bound(remote_addr)) { 1174 err = -EINVAL; 1175 goto out; 1176 } 1177 } else if (sock->state == SS_CONNECTED) { 1178 remote_addr = &vsk->remote_addr; 1179 1180 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1181 remote_addr->svm_cid = transport->get_local_cid(); 1182 1183 /* XXX Should connect() or this function ensure remote_addr is 1184 * bound? 1185 */ 1186 if (!vsock_addr_bound(&vsk->remote_addr)) { 1187 err = -EINVAL; 1188 goto out; 1189 } 1190 } else { 1191 err = -EINVAL; 1192 goto out; 1193 } 1194 1195 if (!transport->dgram_allow(remote_addr->svm_cid, 1196 remote_addr->svm_port)) { 1197 err = -EINVAL; 1198 goto out; 1199 } 1200 1201 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1202 1203 out: 1204 release_sock(sk); 1205 return err; 1206 } 1207 1208 static int vsock_dgram_connect(struct socket *sock, 1209 struct sockaddr *addr, int addr_len, int flags) 1210 { 1211 int err; 1212 struct sock *sk; 1213 struct vsock_sock *vsk; 1214 struct sockaddr_vm *remote_addr; 1215 1216 sk = sock->sk; 1217 vsk = vsock_sk(sk); 1218 1219 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1220 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1221 lock_sock(sk); 1222 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1223 VMADDR_PORT_ANY); 1224 sock->state = SS_UNCONNECTED; 1225 release_sock(sk); 1226 return 0; 1227 } else if (err != 0) 1228 return -EINVAL; 1229 1230 lock_sock(sk); 1231 1232 err = vsock_auto_bind(vsk); 1233 if (err) 1234 goto out; 1235 1236 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1237 remote_addr->svm_port)) { 1238 err = -EINVAL; 1239 goto out; 1240 } 1241 1242 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1243 sock->state = SS_CONNECTED; 1244 1245 out: 1246 release_sock(sk); 1247 return err; 1248 } 1249 1250 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1251 size_t len, int flags) 1252 { 1253 struct vsock_sock *vsk = vsock_sk(sock->sk); 1254 1255 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1256 } 1257 1258 static const struct proto_ops vsock_dgram_ops = { 1259 .family = PF_VSOCK, 1260 .owner = THIS_MODULE, 1261 .release = vsock_release, 1262 .bind = vsock_bind, 1263 .connect = vsock_dgram_connect, 1264 .socketpair = sock_no_socketpair, 1265 .accept = sock_no_accept, 1266 .getname = vsock_getname, 1267 .poll = vsock_poll, 1268 .ioctl = sock_no_ioctl, 1269 .listen = sock_no_listen, 1270 .shutdown = vsock_shutdown, 1271 .sendmsg = vsock_dgram_sendmsg, 1272 .recvmsg = vsock_dgram_recvmsg, 1273 .mmap = sock_no_mmap, 1274 .sendpage = sock_no_sendpage, 1275 }; 1276 1277 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1278 { 1279 const struct vsock_transport *transport = vsk->transport; 1280 1281 if (!transport || !transport->cancel_pkt) 1282 return -EOPNOTSUPP; 1283 1284 return transport->cancel_pkt(vsk); 1285 } 1286 1287 static void vsock_connect_timeout(struct work_struct *work) 1288 { 1289 struct sock *sk; 1290 struct vsock_sock *vsk; 1291 1292 vsk = container_of(work, struct vsock_sock, connect_work.work); 1293 sk = sk_vsock(vsk); 1294 1295 lock_sock(sk); 1296 if (sk->sk_state == TCP_SYN_SENT && 1297 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1298 sk->sk_state = TCP_CLOSE; 1299 sk->sk_socket->state = SS_UNCONNECTED; 1300 sk->sk_err = ETIMEDOUT; 1301 sk_error_report(sk); 1302 vsock_transport_cancel_pkt(vsk); 1303 } 1304 release_sock(sk); 1305 1306 sock_put(sk); 1307 } 1308 1309 static int vsock_connect(struct socket *sock, struct sockaddr *addr, 1310 int addr_len, int flags) 1311 { 1312 int err; 1313 struct sock *sk; 1314 struct vsock_sock *vsk; 1315 const struct vsock_transport *transport; 1316 struct sockaddr_vm *remote_addr; 1317 long timeout; 1318 DEFINE_WAIT(wait); 1319 1320 err = 0; 1321 sk = sock->sk; 1322 vsk = vsock_sk(sk); 1323 1324 lock_sock(sk); 1325 1326 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1327 switch (sock->state) { 1328 case SS_CONNECTED: 1329 err = -EISCONN; 1330 goto out; 1331 case SS_DISCONNECTING: 1332 err = -EINVAL; 1333 goto out; 1334 case SS_CONNECTING: 1335 /* This continues on so we can move sock into the SS_CONNECTED 1336 * state once the connection has completed (at which point err 1337 * will be set to zero also). Otherwise, we will either wait 1338 * for the connection or return -EALREADY should this be a 1339 * non-blocking call. 1340 */ 1341 err = -EALREADY; 1342 if (flags & O_NONBLOCK) 1343 goto out; 1344 break; 1345 default: 1346 if ((sk->sk_state == TCP_LISTEN) || 1347 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1348 err = -EINVAL; 1349 goto out; 1350 } 1351 1352 /* Set the remote address that we are connecting to. */ 1353 memcpy(&vsk->remote_addr, remote_addr, 1354 sizeof(vsk->remote_addr)); 1355 1356 err = vsock_assign_transport(vsk, NULL); 1357 if (err) 1358 goto out; 1359 1360 transport = vsk->transport; 1361 1362 /* The hypervisor and well-known contexts do not have socket 1363 * endpoints. 1364 */ 1365 if (!transport || 1366 !transport->stream_allow(remote_addr->svm_cid, 1367 remote_addr->svm_port)) { 1368 err = -ENETUNREACH; 1369 goto out; 1370 } 1371 1372 err = vsock_auto_bind(vsk); 1373 if (err) 1374 goto out; 1375 1376 sk->sk_state = TCP_SYN_SENT; 1377 1378 err = transport->connect(vsk); 1379 if (err < 0) 1380 goto out; 1381 1382 /* Mark sock as connecting and set the error code to in 1383 * progress in case this is a non-blocking connect. 1384 */ 1385 sock->state = SS_CONNECTING; 1386 err = -EINPROGRESS; 1387 } 1388 1389 /* The receive path will handle all communication until we are able to 1390 * enter the connected state. Here we wait for the connection to be 1391 * completed or a notification of an error. 1392 */ 1393 timeout = vsk->connect_timeout; 1394 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1395 1396 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1397 if (flags & O_NONBLOCK) { 1398 /* If we're not going to block, we schedule a timeout 1399 * function to generate a timeout on the connection 1400 * attempt, in case the peer doesn't respond in a 1401 * timely manner. We hold on to the socket until the 1402 * timeout fires. 1403 */ 1404 sock_hold(sk); 1405 1406 /* If the timeout function is already scheduled, 1407 * reschedule it, then ungrab the socket refcount to 1408 * keep it balanced. 1409 */ 1410 if (mod_delayed_work(system_wq, &vsk->connect_work, 1411 timeout)) 1412 sock_put(sk); 1413 1414 /* Skip ahead to preserve error code set above. */ 1415 goto out_wait; 1416 } 1417 1418 release_sock(sk); 1419 timeout = schedule_timeout(timeout); 1420 lock_sock(sk); 1421 1422 if (signal_pending(current)) { 1423 err = sock_intr_errno(timeout); 1424 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; 1425 sock->state = SS_UNCONNECTED; 1426 vsock_transport_cancel_pkt(vsk); 1427 vsock_remove_connected(vsk); 1428 goto out_wait; 1429 } else if (timeout == 0) { 1430 err = -ETIMEDOUT; 1431 sk->sk_state = TCP_CLOSE; 1432 sock->state = SS_UNCONNECTED; 1433 vsock_transport_cancel_pkt(vsk); 1434 goto out_wait; 1435 } 1436 1437 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1438 } 1439 1440 if (sk->sk_err) { 1441 err = -sk->sk_err; 1442 sk->sk_state = TCP_CLOSE; 1443 sock->state = SS_UNCONNECTED; 1444 } else { 1445 err = 0; 1446 } 1447 1448 out_wait: 1449 finish_wait(sk_sleep(sk), &wait); 1450 out: 1451 release_sock(sk); 1452 return err; 1453 } 1454 1455 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1456 bool kern) 1457 { 1458 struct sock *listener; 1459 int err; 1460 struct sock *connected; 1461 struct vsock_sock *vconnected; 1462 long timeout; 1463 DEFINE_WAIT(wait); 1464 1465 err = 0; 1466 listener = sock->sk; 1467 1468 lock_sock(listener); 1469 1470 if (!sock_type_connectible(sock->type)) { 1471 err = -EOPNOTSUPP; 1472 goto out; 1473 } 1474 1475 if (listener->sk_state != TCP_LISTEN) { 1476 err = -EINVAL; 1477 goto out; 1478 } 1479 1480 /* Wait for children sockets to appear; these are the new sockets 1481 * created upon connection establishment. 1482 */ 1483 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1484 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1485 1486 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1487 listener->sk_err == 0) { 1488 release_sock(listener); 1489 timeout = schedule_timeout(timeout); 1490 finish_wait(sk_sleep(listener), &wait); 1491 lock_sock(listener); 1492 1493 if (signal_pending(current)) { 1494 err = sock_intr_errno(timeout); 1495 goto out; 1496 } else if (timeout == 0) { 1497 err = -EAGAIN; 1498 goto out; 1499 } 1500 1501 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1502 } 1503 finish_wait(sk_sleep(listener), &wait); 1504 1505 if (listener->sk_err) 1506 err = -listener->sk_err; 1507 1508 if (connected) { 1509 sk_acceptq_removed(listener); 1510 1511 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1512 vconnected = vsock_sk(connected); 1513 1514 /* If the listener socket has received an error, then we should 1515 * reject this socket and return. Note that we simply mark the 1516 * socket rejected, drop our reference, and let the cleanup 1517 * function handle the cleanup; the fact that we found it in 1518 * the listener's accept queue guarantees that the cleanup 1519 * function hasn't run yet. 1520 */ 1521 if (err) { 1522 vconnected->rejected = true; 1523 } else { 1524 newsock->state = SS_CONNECTED; 1525 sock_graft(connected, newsock); 1526 } 1527 1528 release_sock(connected); 1529 sock_put(connected); 1530 } 1531 1532 out: 1533 release_sock(listener); 1534 return err; 1535 } 1536 1537 static int vsock_listen(struct socket *sock, int backlog) 1538 { 1539 int err; 1540 struct sock *sk; 1541 struct vsock_sock *vsk; 1542 1543 sk = sock->sk; 1544 1545 lock_sock(sk); 1546 1547 if (!sock_type_connectible(sk->sk_type)) { 1548 err = -EOPNOTSUPP; 1549 goto out; 1550 } 1551 1552 if (sock->state != SS_UNCONNECTED) { 1553 err = -EINVAL; 1554 goto out; 1555 } 1556 1557 vsk = vsock_sk(sk); 1558 1559 if (!vsock_addr_bound(&vsk->local_addr)) { 1560 err = -EINVAL; 1561 goto out; 1562 } 1563 1564 sk->sk_max_ack_backlog = backlog; 1565 sk->sk_state = TCP_LISTEN; 1566 1567 err = 0; 1568 1569 out: 1570 release_sock(sk); 1571 return err; 1572 } 1573 1574 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1575 const struct vsock_transport *transport, 1576 u64 val) 1577 { 1578 if (val > vsk->buffer_max_size) 1579 val = vsk->buffer_max_size; 1580 1581 if (val < vsk->buffer_min_size) 1582 val = vsk->buffer_min_size; 1583 1584 if (val != vsk->buffer_size && 1585 transport && transport->notify_buffer_size) 1586 transport->notify_buffer_size(vsk, &val); 1587 1588 vsk->buffer_size = val; 1589 } 1590 1591 static int vsock_connectible_setsockopt(struct socket *sock, 1592 int level, 1593 int optname, 1594 sockptr_t optval, 1595 unsigned int optlen) 1596 { 1597 int err; 1598 struct sock *sk; 1599 struct vsock_sock *vsk; 1600 const struct vsock_transport *transport; 1601 u64 val; 1602 1603 if (level != AF_VSOCK) 1604 return -ENOPROTOOPT; 1605 1606 #define COPY_IN(_v) \ 1607 do { \ 1608 if (optlen < sizeof(_v)) { \ 1609 err = -EINVAL; \ 1610 goto exit; \ 1611 } \ 1612 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1613 err = -EFAULT; \ 1614 goto exit; \ 1615 } \ 1616 } while (0) 1617 1618 err = 0; 1619 sk = sock->sk; 1620 vsk = vsock_sk(sk); 1621 1622 lock_sock(sk); 1623 1624 transport = vsk->transport; 1625 1626 switch (optname) { 1627 case SO_VM_SOCKETS_BUFFER_SIZE: 1628 COPY_IN(val); 1629 vsock_update_buffer_size(vsk, transport, val); 1630 break; 1631 1632 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1633 COPY_IN(val); 1634 vsk->buffer_max_size = val; 1635 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1636 break; 1637 1638 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1639 COPY_IN(val); 1640 vsk->buffer_min_size = val; 1641 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1642 break; 1643 1644 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1645 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: { 1646 struct __kernel_sock_timeval tv; 1647 1648 err = sock_copy_user_timeval(&tv, optval, optlen, 1649 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1650 if (err) 1651 break; 1652 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1653 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1654 vsk->connect_timeout = tv.tv_sec * HZ + 1655 DIV_ROUND_UP((unsigned long)tv.tv_usec, (USEC_PER_SEC / HZ)); 1656 if (vsk->connect_timeout == 0) 1657 vsk->connect_timeout = 1658 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1659 1660 } else { 1661 err = -ERANGE; 1662 } 1663 break; 1664 } 1665 1666 default: 1667 err = -ENOPROTOOPT; 1668 break; 1669 } 1670 1671 #undef COPY_IN 1672 1673 exit: 1674 release_sock(sk); 1675 return err; 1676 } 1677 1678 static int vsock_connectible_getsockopt(struct socket *sock, 1679 int level, int optname, 1680 char __user *optval, 1681 int __user *optlen) 1682 { 1683 struct sock *sk = sock->sk; 1684 struct vsock_sock *vsk = vsock_sk(sk); 1685 1686 union { 1687 u64 val64; 1688 struct old_timeval32 tm32; 1689 struct __kernel_old_timeval tm; 1690 struct __kernel_sock_timeval stm; 1691 } v; 1692 1693 int lv = sizeof(v.val64); 1694 int len; 1695 1696 if (level != AF_VSOCK) 1697 return -ENOPROTOOPT; 1698 1699 if (get_user(len, optlen)) 1700 return -EFAULT; 1701 1702 memset(&v, 0, sizeof(v)); 1703 1704 switch (optname) { 1705 case SO_VM_SOCKETS_BUFFER_SIZE: 1706 v.val64 = vsk->buffer_size; 1707 break; 1708 1709 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1710 v.val64 = vsk->buffer_max_size; 1711 break; 1712 1713 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1714 v.val64 = vsk->buffer_min_size; 1715 break; 1716 1717 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1718 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: 1719 lv = sock_get_timeout(vsk->connect_timeout, &v, 1720 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1721 break; 1722 1723 default: 1724 return -ENOPROTOOPT; 1725 } 1726 1727 if (len < lv) 1728 return -EINVAL; 1729 if (len > lv) 1730 len = lv; 1731 if (copy_to_user(optval, &v, len)) 1732 return -EFAULT; 1733 1734 if (put_user(len, optlen)) 1735 return -EFAULT; 1736 1737 return 0; 1738 } 1739 1740 static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, 1741 size_t len) 1742 { 1743 struct sock *sk; 1744 struct vsock_sock *vsk; 1745 const struct vsock_transport *transport; 1746 ssize_t total_written; 1747 long timeout; 1748 int err; 1749 struct vsock_transport_send_notify_data send_data; 1750 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1751 1752 sk = sock->sk; 1753 vsk = vsock_sk(sk); 1754 total_written = 0; 1755 err = 0; 1756 1757 if (msg->msg_flags & MSG_OOB) 1758 return -EOPNOTSUPP; 1759 1760 lock_sock(sk); 1761 1762 transport = vsk->transport; 1763 1764 /* Callers should not provide a destination with connection oriented 1765 * sockets. 1766 */ 1767 if (msg->msg_namelen) { 1768 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1769 goto out; 1770 } 1771 1772 /* Send data only if both sides are not shutdown in the direction. */ 1773 if (sk->sk_shutdown & SEND_SHUTDOWN || 1774 vsk->peer_shutdown & RCV_SHUTDOWN) { 1775 err = -EPIPE; 1776 goto out; 1777 } 1778 1779 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1780 !vsock_addr_bound(&vsk->local_addr)) { 1781 err = -ENOTCONN; 1782 goto out; 1783 } 1784 1785 if (!vsock_addr_bound(&vsk->remote_addr)) { 1786 err = -EDESTADDRREQ; 1787 goto out; 1788 } 1789 1790 /* Wait for room in the produce queue to enqueue our user's data. */ 1791 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1792 1793 err = transport->notify_send_init(vsk, &send_data); 1794 if (err < 0) 1795 goto out; 1796 1797 while (total_written < len) { 1798 ssize_t written; 1799 1800 add_wait_queue(sk_sleep(sk), &wait); 1801 while (vsock_stream_has_space(vsk) == 0 && 1802 sk->sk_err == 0 && 1803 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1804 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1805 1806 /* Don't wait for non-blocking sockets. */ 1807 if (timeout == 0) { 1808 err = -EAGAIN; 1809 remove_wait_queue(sk_sleep(sk), &wait); 1810 goto out_err; 1811 } 1812 1813 err = transport->notify_send_pre_block(vsk, &send_data); 1814 if (err < 0) { 1815 remove_wait_queue(sk_sleep(sk), &wait); 1816 goto out_err; 1817 } 1818 1819 release_sock(sk); 1820 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1821 lock_sock(sk); 1822 if (signal_pending(current)) { 1823 err = sock_intr_errno(timeout); 1824 remove_wait_queue(sk_sleep(sk), &wait); 1825 goto out_err; 1826 } else if (timeout == 0) { 1827 err = -EAGAIN; 1828 remove_wait_queue(sk_sleep(sk), &wait); 1829 goto out_err; 1830 } 1831 } 1832 remove_wait_queue(sk_sleep(sk), &wait); 1833 1834 /* These checks occur both as part of and after the loop 1835 * conditional since we need to check before and after 1836 * sleeping. 1837 */ 1838 if (sk->sk_err) { 1839 err = -sk->sk_err; 1840 goto out_err; 1841 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1842 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1843 err = -EPIPE; 1844 goto out_err; 1845 } 1846 1847 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1848 if (err < 0) 1849 goto out_err; 1850 1851 /* Note that enqueue will only write as many bytes as are free 1852 * in the produce queue, so we don't need to ensure len is 1853 * smaller than the queue size. It is the caller's 1854 * responsibility to check how many bytes we were able to send. 1855 */ 1856 1857 if (sk->sk_type == SOCK_SEQPACKET) { 1858 written = transport->seqpacket_enqueue(vsk, 1859 msg, len - total_written); 1860 } else { 1861 written = transport->stream_enqueue(vsk, 1862 msg, len - total_written); 1863 } 1864 1865 if (written < 0) { 1866 err = written; 1867 goto out_err; 1868 } 1869 1870 total_written += written; 1871 1872 err = transport->notify_send_post_enqueue( 1873 vsk, written, &send_data); 1874 if (err < 0) 1875 goto out_err; 1876 1877 } 1878 1879 out_err: 1880 if (total_written > 0) { 1881 /* Return number of written bytes only if: 1882 * 1) SOCK_STREAM socket. 1883 * 2) SOCK_SEQPACKET socket when whole buffer is sent. 1884 */ 1885 if (sk->sk_type == SOCK_STREAM || total_written == len) 1886 err = total_written; 1887 } 1888 out: 1889 release_sock(sk); 1890 return err; 1891 } 1892 1893 static int vsock_connectible_wait_data(struct sock *sk, 1894 struct wait_queue_entry *wait, 1895 long timeout, 1896 struct vsock_transport_recv_notify_data *recv_data, 1897 size_t target) 1898 { 1899 const struct vsock_transport *transport; 1900 struct vsock_sock *vsk; 1901 s64 data; 1902 int err; 1903 1904 vsk = vsock_sk(sk); 1905 err = 0; 1906 transport = vsk->transport; 1907 1908 while (1) { 1909 prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); 1910 data = vsock_connectible_has_data(vsk); 1911 if (data != 0) 1912 break; 1913 1914 if (sk->sk_err != 0 || 1915 (sk->sk_shutdown & RCV_SHUTDOWN) || 1916 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1917 break; 1918 } 1919 1920 /* Don't wait for non-blocking sockets. */ 1921 if (timeout == 0) { 1922 err = -EAGAIN; 1923 break; 1924 } 1925 1926 if (recv_data) { 1927 err = transport->notify_recv_pre_block(vsk, target, recv_data); 1928 if (err < 0) 1929 break; 1930 } 1931 1932 release_sock(sk); 1933 timeout = schedule_timeout(timeout); 1934 lock_sock(sk); 1935 1936 if (signal_pending(current)) { 1937 err = sock_intr_errno(timeout); 1938 break; 1939 } else if (timeout == 0) { 1940 err = -EAGAIN; 1941 break; 1942 } 1943 } 1944 1945 finish_wait(sk_sleep(sk), wait); 1946 1947 if (err) 1948 return err; 1949 1950 /* Internal transport error when checking for available 1951 * data. XXX This should be changed to a connection 1952 * reset in a later change. 1953 */ 1954 if (data < 0) 1955 return -ENOMEM; 1956 1957 return data; 1958 } 1959 1960 static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, 1961 size_t len, int flags) 1962 { 1963 struct vsock_transport_recv_notify_data recv_data; 1964 const struct vsock_transport *transport; 1965 struct vsock_sock *vsk; 1966 ssize_t copied; 1967 size_t target; 1968 long timeout; 1969 int err; 1970 1971 DEFINE_WAIT(wait); 1972 1973 vsk = vsock_sk(sk); 1974 transport = vsk->transport; 1975 1976 /* We must not copy less than target bytes into the user's buffer 1977 * before returning successfully, so we wait for the consume queue to 1978 * have that much data to consume before dequeueing. Note that this 1979 * makes it impossible to handle cases where target is greater than the 1980 * queue size. 1981 */ 1982 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1983 if (target >= transport->stream_rcvhiwat(vsk)) { 1984 err = -ENOMEM; 1985 goto out; 1986 } 1987 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1988 copied = 0; 1989 1990 err = transport->notify_recv_init(vsk, target, &recv_data); 1991 if (err < 0) 1992 goto out; 1993 1994 1995 while (1) { 1996 ssize_t read; 1997 1998 err = vsock_connectible_wait_data(sk, &wait, timeout, 1999 &recv_data, target); 2000 if (err <= 0) 2001 break; 2002 2003 err = transport->notify_recv_pre_dequeue(vsk, target, 2004 &recv_data); 2005 if (err < 0) 2006 break; 2007 2008 read = transport->stream_dequeue(vsk, msg, len - copied, flags); 2009 if (read < 0) { 2010 err = -ENOMEM; 2011 break; 2012 } 2013 2014 copied += read; 2015 2016 err = transport->notify_recv_post_dequeue(vsk, target, read, 2017 !(flags & MSG_PEEK), &recv_data); 2018 if (err < 0) 2019 goto out; 2020 2021 if (read >= target || flags & MSG_PEEK) 2022 break; 2023 2024 target -= read; 2025 } 2026 2027 if (sk->sk_err) 2028 err = -sk->sk_err; 2029 else if (sk->sk_shutdown & RCV_SHUTDOWN) 2030 err = 0; 2031 2032 if (copied > 0) 2033 err = copied; 2034 2035 out: 2036 return err; 2037 } 2038 2039 static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, 2040 size_t len, int flags) 2041 { 2042 const struct vsock_transport *transport; 2043 struct vsock_sock *vsk; 2044 ssize_t msg_len; 2045 long timeout; 2046 int err = 0; 2047 DEFINE_WAIT(wait); 2048 2049 vsk = vsock_sk(sk); 2050 transport = vsk->transport; 2051 2052 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2053 2054 err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0); 2055 if (err <= 0) 2056 goto out; 2057 2058 msg_len = transport->seqpacket_dequeue(vsk, msg, flags); 2059 2060 if (msg_len < 0) { 2061 err = -ENOMEM; 2062 goto out; 2063 } 2064 2065 if (sk->sk_err) { 2066 err = -sk->sk_err; 2067 } else if (sk->sk_shutdown & RCV_SHUTDOWN) { 2068 err = 0; 2069 } else { 2070 /* User sets MSG_TRUNC, so return real length of 2071 * packet. 2072 */ 2073 if (flags & MSG_TRUNC) 2074 err = msg_len; 2075 else 2076 err = len - msg_data_left(msg); 2077 2078 /* Always set MSG_TRUNC if real length of packet is 2079 * bigger than user's buffer. 2080 */ 2081 if (msg_len > len) 2082 msg->msg_flags |= MSG_TRUNC; 2083 } 2084 2085 out: 2086 return err; 2087 } 2088 2089 static int 2090 vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2091 int flags) 2092 { 2093 struct sock *sk; 2094 struct vsock_sock *vsk; 2095 const struct vsock_transport *transport; 2096 int err; 2097 2098 sk = sock->sk; 2099 vsk = vsock_sk(sk); 2100 err = 0; 2101 2102 lock_sock(sk); 2103 2104 transport = vsk->transport; 2105 2106 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 2107 /* Recvmsg is supposed to return 0 if a peer performs an 2108 * orderly shutdown. Differentiate between that case and when a 2109 * peer has not connected or a local shutdown occurred with the 2110 * SOCK_DONE flag. 2111 */ 2112 if (sock_flag(sk, SOCK_DONE)) 2113 err = 0; 2114 else 2115 err = -ENOTCONN; 2116 2117 goto out; 2118 } 2119 2120 if (flags & MSG_OOB) { 2121 err = -EOPNOTSUPP; 2122 goto out; 2123 } 2124 2125 /* We don't check peer_shutdown flag here since peer may actually shut 2126 * down, but there can be data in the queue that a local socket can 2127 * receive. 2128 */ 2129 if (sk->sk_shutdown & RCV_SHUTDOWN) { 2130 err = 0; 2131 goto out; 2132 } 2133 2134 /* It is valid on Linux to pass in a zero-length receive buffer. This 2135 * is not an error. We may as well bail out now. 2136 */ 2137 if (!len) { 2138 err = 0; 2139 goto out; 2140 } 2141 2142 if (sk->sk_type == SOCK_STREAM) 2143 err = __vsock_stream_recvmsg(sk, msg, len, flags); 2144 else 2145 err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); 2146 2147 out: 2148 release_sock(sk); 2149 return err; 2150 } 2151 2152 static int vsock_set_rcvlowat(struct sock *sk, int val) 2153 { 2154 const struct vsock_transport *transport; 2155 struct vsock_sock *vsk; 2156 2157 vsk = vsock_sk(sk); 2158 2159 if (val > vsk->buffer_size) 2160 return -EINVAL; 2161 2162 transport = vsk->transport; 2163 2164 if (transport && transport->set_rcvlowat) 2165 return transport->set_rcvlowat(vsk, val); 2166 2167 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 2168 return 0; 2169 } 2170 2171 static const struct proto_ops vsock_stream_ops = { 2172 .family = PF_VSOCK, 2173 .owner = THIS_MODULE, 2174 .release = vsock_release, 2175 .bind = vsock_bind, 2176 .connect = vsock_connect, 2177 .socketpair = sock_no_socketpair, 2178 .accept = vsock_accept, 2179 .getname = vsock_getname, 2180 .poll = vsock_poll, 2181 .ioctl = sock_no_ioctl, 2182 .listen = vsock_listen, 2183 .shutdown = vsock_shutdown, 2184 .setsockopt = vsock_connectible_setsockopt, 2185 .getsockopt = vsock_connectible_getsockopt, 2186 .sendmsg = vsock_connectible_sendmsg, 2187 .recvmsg = vsock_connectible_recvmsg, 2188 .mmap = sock_no_mmap, 2189 .sendpage = sock_no_sendpage, 2190 .set_rcvlowat = vsock_set_rcvlowat, 2191 }; 2192 2193 static const struct proto_ops vsock_seqpacket_ops = { 2194 .family = PF_VSOCK, 2195 .owner = THIS_MODULE, 2196 .release = vsock_release, 2197 .bind = vsock_bind, 2198 .connect = vsock_connect, 2199 .socketpair = sock_no_socketpair, 2200 .accept = vsock_accept, 2201 .getname = vsock_getname, 2202 .poll = vsock_poll, 2203 .ioctl = sock_no_ioctl, 2204 .listen = vsock_listen, 2205 .shutdown = vsock_shutdown, 2206 .setsockopt = vsock_connectible_setsockopt, 2207 .getsockopt = vsock_connectible_getsockopt, 2208 .sendmsg = vsock_connectible_sendmsg, 2209 .recvmsg = vsock_connectible_recvmsg, 2210 .mmap = sock_no_mmap, 2211 .sendpage = sock_no_sendpage, 2212 }; 2213 2214 static int vsock_create(struct net *net, struct socket *sock, 2215 int protocol, int kern) 2216 { 2217 struct vsock_sock *vsk; 2218 struct sock *sk; 2219 int ret; 2220 2221 if (!sock) 2222 return -EINVAL; 2223 2224 if (protocol && protocol != PF_VSOCK) 2225 return -EPROTONOSUPPORT; 2226 2227 switch (sock->type) { 2228 case SOCK_DGRAM: 2229 sock->ops = &vsock_dgram_ops; 2230 break; 2231 case SOCK_STREAM: 2232 sock->ops = &vsock_stream_ops; 2233 break; 2234 case SOCK_SEQPACKET: 2235 sock->ops = &vsock_seqpacket_ops; 2236 break; 2237 default: 2238 return -ESOCKTNOSUPPORT; 2239 } 2240 2241 sock->state = SS_UNCONNECTED; 2242 2243 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2244 if (!sk) 2245 return -ENOMEM; 2246 2247 vsk = vsock_sk(sk); 2248 2249 if (sock->type == SOCK_DGRAM) { 2250 ret = vsock_assign_transport(vsk, NULL); 2251 if (ret < 0) { 2252 sock_put(sk); 2253 return ret; 2254 } 2255 } 2256 2257 vsock_insert_unbound(vsk); 2258 2259 return 0; 2260 } 2261 2262 static const struct net_proto_family vsock_family_ops = { 2263 .family = AF_VSOCK, 2264 .create = vsock_create, 2265 .owner = THIS_MODULE, 2266 }; 2267 2268 static long vsock_dev_do_ioctl(struct file *filp, 2269 unsigned int cmd, void __user *ptr) 2270 { 2271 u32 __user *p = ptr; 2272 u32 cid = VMADDR_CID_ANY; 2273 int retval = 0; 2274 2275 switch (cmd) { 2276 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2277 /* To be compatible with the VMCI behavior, we prioritize the 2278 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2279 */ 2280 if (transport_g2h) 2281 cid = transport_g2h->get_local_cid(); 2282 else if (transport_h2g) 2283 cid = transport_h2g->get_local_cid(); 2284 2285 if (put_user(cid, p) != 0) 2286 retval = -EFAULT; 2287 break; 2288 2289 default: 2290 retval = -ENOIOCTLCMD; 2291 } 2292 2293 return retval; 2294 } 2295 2296 static long vsock_dev_ioctl(struct file *filp, 2297 unsigned int cmd, unsigned long arg) 2298 { 2299 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2300 } 2301 2302 #ifdef CONFIG_COMPAT 2303 static long vsock_dev_compat_ioctl(struct file *filp, 2304 unsigned int cmd, unsigned long arg) 2305 { 2306 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2307 } 2308 #endif 2309 2310 static const struct file_operations vsock_device_ops = { 2311 .owner = THIS_MODULE, 2312 .unlocked_ioctl = vsock_dev_ioctl, 2313 #ifdef CONFIG_COMPAT 2314 .compat_ioctl = vsock_dev_compat_ioctl, 2315 #endif 2316 .open = nonseekable_open, 2317 }; 2318 2319 static struct miscdevice vsock_device = { 2320 .name = "vsock", 2321 .fops = &vsock_device_ops, 2322 }; 2323 2324 static int __init vsock_init(void) 2325 { 2326 int err = 0; 2327 2328 vsock_init_tables(); 2329 2330 vsock_proto.owner = THIS_MODULE; 2331 vsock_device.minor = MISC_DYNAMIC_MINOR; 2332 err = misc_register(&vsock_device); 2333 if (err) { 2334 pr_err("Failed to register misc device\n"); 2335 goto err_reset_transport; 2336 } 2337 2338 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2339 if (err) { 2340 pr_err("Cannot register vsock protocol\n"); 2341 goto err_deregister_misc; 2342 } 2343 2344 err = sock_register(&vsock_family_ops); 2345 if (err) { 2346 pr_err("could not register af_vsock (%d) address family: %d\n", 2347 AF_VSOCK, err); 2348 goto err_unregister_proto; 2349 } 2350 2351 return 0; 2352 2353 err_unregister_proto: 2354 proto_unregister(&vsock_proto); 2355 err_deregister_misc: 2356 misc_deregister(&vsock_device); 2357 err_reset_transport: 2358 return err; 2359 } 2360 2361 static void __exit vsock_exit(void) 2362 { 2363 misc_deregister(&vsock_device); 2364 sock_unregister(AF_VSOCK); 2365 proto_unregister(&vsock_proto); 2366 } 2367 2368 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2369 { 2370 return vsk->transport; 2371 } 2372 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2373 2374 int vsock_core_register(const struct vsock_transport *t, int features) 2375 { 2376 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2377 int err = mutex_lock_interruptible(&vsock_register_mutex); 2378 2379 if (err) 2380 return err; 2381 2382 t_h2g = transport_h2g; 2383 t_g2h = transport_g2h; 2384 t_dgram = transport_dgram; 2385 t_local = transport_local; 2386 2387 if (features & VSOCK_TRANSPORT_F_H2G) { 2388 if (t_h2g) { 2389 err = -EBUSY; 2390 goto err_busy; 2391 } 2392 t_h2g = t; 2393 } 2394 2395 if (features & VSOCK_TRANSPORT_F_G2H) { 2396 if (t_g2h) { 2397 err = -EBUSY; 2398 goto err_busy; 2399 } 2400 t_g2h = t; 2401 } 2402 2403 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2404 if (t_dgram) { 2405 err = -EBUSY; 2406 goto err_busy; 2407 } 2408 t_dgram = t; 2409 } 2410 2411 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2412 if (t_local) { 2413 err = -EBUSY; 2414 goto err_busy; 2415 } 2416 t_local = t; 2417 } 2418 2419 transport_h2g = t_h2g; 2420 transport_g2h = t_g2h; 2421 transport_dgram = t_dgram; 2422 transport_local = t_local; 2423 2424 err_busy: 2425 mutex_unlock(&vsock_register_mutex); 2426 return err; 2427 } 2428 EXPORT_SYMBOL_GPL(vsock_core_register); 2429 2430 void vsock_core_unregister(const struct vsock_transport *t) 2431 { 2432 mutex_lock(&vsock_register_mutex); 2433 2434 if (transport_h2g == t) 2435 transport_h2g = NULL; 2436 2437 if (transport_g2h == t) 2438 transport_g2h = NULL; 2439 2440 if (transport_dgram == t) 2441 transport_dgram = NULL; 2442 2443 if (transport_local == t) 2444 transport_local = NULL; 2445 2446 mutex_unlock(&vsock_register_mutex); 2447 } 2448 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2449 2450 module_init(vsock_init); 2451 module_exit(vsock_exit); 2452 2453 MODULE_AUTHOR("VMware, Inc."); 2454 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2455 MODULE_VERSION("1.0.2.0-k"); 2456 MODULE_LICENSE("GPL v2"); 2457