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 = LAST_RESERVED_PORT + 1 + 630 prandom_u32_max(U32_MAX - LAST_RESERVED_PORT); 631 632 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 633 634 if (addr->svm_port == VMADDR_PORT_ANY) { 635 bool found = false; 636 unsigned int i; 637 638 for (i = 0; i < MAX_PORT_RETRIES; i++) { 639 if (port <= LAST_RESERVED_PORT) 640 port = LAST_RESERVED_PORT + 1; 641 642 new_addr.svm_port = port++; 643 644 if (!__vsock_find_bound_socket(&new_addr)) { 645 found = true; 646 break; 647 } 648 } 649 650 if (!found) 651 return -EADDRNOTAVAIL; 652 } else { 653 /* If port is in reserved range, ensure caller 654 * has necessary privileges. 655 */ 656 if (addr->svm_port <= LAST_RESERVED_PORT && 657 !capable(CAP_NET_BIND_SERVICE)) { 658 return -EACCES; 659 } 660 661 if (__vsock_find_bound_socket(&new_addr)) 662 return -EADDRINUSE; 663 } 664 665 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 666 667 /* Remove connection oriented sockets from the unbound list and add them 668 * to the hash table for easy lookup by its address. The unbound list 669 * is simply an extra entry at the end of the hash table, a trick used 670 * by AF_UNIX. 671 */ 672 __vsock_remove_bound(vsk); 673 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 674 675 return 0; 676 } 677 678 static int __vsock_bind_dgram(struct vsock_sock *vsk, 679 struct sockaddr_vm *addr) 680 { 681 return vsk->transport->dgram_bind(vsk, addr); 682 } 683 684 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 685 { 686 struct vsock_sock *vsk = vsock_sk(sk); 687 int retval; 688 689 /* First ensure this socket isn't already bound. */ 690 if (vsock_addr_bound(&vsk->local_addr)) 691 return -EINVAL; 692 693 /* Now bind to the provided address or select appropriate values if 694 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 695 * like AF_INET prevents binding to a non-local IP address (in most 696 * cases), we only allow binding to a local CID. 697 */ 698 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid)) 699 return -EADDRNOTAVAIL; 700 701 switch (sk->sk_socket->type) { 702 case SOCK_STREAM: 703 case SOCK_SEQPACKET: 704 spin_lock_bh(&vsock_table_lock); 705 retval = __vsock_bind_connectible(vsk, addr); 706 spin_unlock_bh(&vsock_table_lock); 707 break; 708 709 case SOCK_DGRAM: 710 retval = __vsock_bind_dgram(vsk, addr); 711 break; 712 713 default: 714 retval = -EINVAL; 715 break; 716 } 717 718 return retval; 719 } 720 721 static void vsock_connect_timeout(struct work_struct *work); 722 723 static struct sock *__vsock_create(struct net *net, 724 struct socket *sock, 725 struct sock *parent, 726 gfp_t priority, 727 unsigned short type, 728 int kern) 729 { 730 struct sock *sk; 731 struct vsock_sock *psk; 732 struct vsock_sock *vsk; 733 734 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 735 if (!sk) 736 return NULL; 737 738 sock_init_data(sock, sk); 739 740 /* sk->sk_type is normally set in sock_init_data, but only if sock is 741 * non-NULL. We make sure that our sockets always have a type by 742 * setting it here if needed. 743 */ 744 if (!sock) 745 sk->sk_type = type; 746 747 vsk = vsock_sk(sk); 748 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 749 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 750 751 sk->sk_destruct = vsock_sk_destruct; 752 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 753 sock_reset_flag(sk, SOCK_DONE); 754 755 INIT_LIST_HEAD(&vsk->bound_table); 756 INIT_LIST_HEAD(&vsk->connected_table); 757 vsk->listener = NULL; 758 INIT_LIST_HEAD(&vsk->pending_links); 759 INIT_LIST_HEAD(&vsk->accept_queue); 760 vsk->rejected = false; 761 vsk->sent_request = false; 762 vsk->ignore_connecting_rst = false; 763 vsk->peer_shutdown = 0; 764 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 765 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 766 767 psk = parent ? vsock_sk(parent) : NULL; 768 if (parent) { 769 vsk->trusted = psk->trusted; 770 vsk->owner = get_cred(psk->owner); 771 vsk->connect_timeout = psk->connect_timeout; 772 vsk->buffer_size = psk->buffer_size; 773 vsk->buffer_min_size = psk->buffer_min_size; 774 vsk->buffer_max_size = psk->buffer_max_size; 775 security_sk_clone(parent, sk); 776 } else { 777 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN); 778 vsk->owner = get_current_cred(); 779 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 780 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE; 781 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE; 782 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE; 783 } 784 785 return sk; 786 } 787 788 static bool sock_type_connectible(u16 type) 789 { 790 return (type == SOCK_STREAM) || (type == SOCK_SEQPACKET); 791 } 792 793 static void __vsock_release(struct sock *sk, int level) 794 { 795 if (sk) { 796 struct sock *pending; 797 struct vsock_sock *vsk; 798 799 vsk = vsock_sk(sk); 800 pending = NULL; /* Compiler warning. */ 801 802 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 803 * version to avoid the warning "possible recursive locking 804 * detected". When "level" is 0, lock_sock_nested(sk, level) 805 * is the same as lock_sock(sk). 806 */ 807 lock_sock_nested(sk, level); 808 809 if (vsk->transport) 810 vsk->transport->release(vsk); 811 else if (sock_type_connectible(sk->sk_type)) 812 vsock_remove_sock(vsk); 813 814 sock_orphan(sk); 815 sk->sk_shutdown = SHUTDOWN_MASK; 816 817 skb_queue_purge(&sk->sk_receive_queue); 818 819 /* Clean up any sockets that never were accepted. */ 820 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 821 __vsock_release(pending, SINGLE_DEPTH_NESTING); 822 sock_put(pending); 823 } 824 825 release_sock(sk); 826 sock_put(sk); 827 } 828 } 829 830 static void vsock_sk_destruct(struct sock *sk) 831 { 832 struct vsock_sock *vsk = vsock_sk(sk); 833 834 vsock_deassign_transport(vsk); 835 836 /* When clearing these addresses, there's no need to set the family and 837 * possibly register the address family with the kernel. 838 */ 839 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 840 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 841 842 put_cred(vsk->owner); 843 } 844 845 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 846 { 847 int err; 848 849 err = sock_queue_rcv_skb(sk, skb); 850 if (err) 851 kfree_skb(skb); 852 853 return err; 854 } 855 856 struct sock *vsock_create_connected(struct sock *parent) 857 { 858 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL, 859 parent->sk_type, 0); 860 } 861 EXPORT_SYMBOL_GPL(vsock_create_connected); 862 863 s64 vsock_stream_has_data(struct vsock_sock *vsk) 864 { 865 return vsk->transport->stream_has_data(vsk); 866 } 867 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 868 869 static s64 vsock_connectible_has_data(struct vsock_sock *vsk) 870 { 871 struct sock *sk = sk_vsock(vsk); 872 873 if (sk->sk_type == SOCK_SEQPACKET) 874 return vsk->transport->seqpacket_has_data(vsk); 875 else 876 return vsock_stream_has_data(vsk); 877 } 878 879 s64 vsock_stream_has_space(struct vsock_sock *vsk) 880 { 881 return vsk->transport->stream_has_space(vsk); 882 } 883 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 884 885 static int vsock_release(struct socket *sock) 886 { 887 __vsock_release(sock->sk, 0); 888 sock->sk = NULL; 889 sock->state = SS_FREE; 890 891 return 0; 892 } 893 894 static int 895 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 896 { 897 int err; 898 struct sock *sk; 899 struct sockaddr_vm *vm_addr; 900 901 sk = sock->sk; 902 903 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 904 return -EINVAL; 905 906 lock_sock(sk); 907 err = __vsock_bind(sk, vm_addr); 908 release_sock(sk); 909 910 return err; 911 } 912 913 static int vsock_getname(struct socket *sock, 914 struct sockaddr *addr, int peer) 915 { 916 int err; 917 struct sock *sk; 918 struct vsock_sock *vsk; 919 struct sockaddr_vm *vm_addr; 920 921 sk = sock->sk; 922 vsk = vsock_sk(sk); 923 err = 0; 924 925 lock_sock(sk); 926 927 if (peer) { 928 if (sock->state != SS_CONNECTED) { 929 err = -ENOTCONN; 930 goto out; 931 } 932 vm_addr = &vsk->remote_addr; 933 } else { 934 vm_addr = &vsk->local_addr; 935 } 936 937 if (!vm_addr) { 938 err = -EINVAL; 939 goto out; 940 } 941 942 /* sys_getsockname() and sys_getpeername() pass us a 943 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 944 * that macro is defined in socket.c instead of .h, so we hardcode its 945 * value here. 946 */ 947 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 948 memcpy(addr, vm_addr, sizeof(*vm_addr)); 949 err = sizeof(*vm_addr); 950 951 out: 952 release_sock(sk); 953 return err; 954 } 955 956 static int vsock_shutdown(struct socket *sock, int mode) 957 { 958 int err; 959 struct sock *sk; 960 961 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 962 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 963 * here like the other address families do. Note also that the 964 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 965 * which is what we want. 966 */ 967 mode++; 968 969 if ((mode & ~SHUTDOWN_MASK) || !mode) 970 return -EINVAL; 971 972 /* If this is a connection oriented socket and it is not connected then 973 * bail out immediately. If it is a DGRAM socket then we must first 974 * kick the socket so that it wakes up from any sleeping calls, for 975 * example recv(), and then afterwards return the error. 976 */ 977 978 sk = sock->sk; 979 980 lock_sock(sk); 981 if (sock->state == SS_UNCONNECTED) { 982 err = -ENOTCONN; 983 if (sock_type_connectible(sk->sk_type)) 984 goto out; 985 } else { 986 sock->state = SS_DISCONNECTING; 987 err = 0; 988 } 989 990 /* Receive and send shutdowns are treated alike. */ 991 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 992 if (mode) { 993 sk->sk_shutdown |= mode; 994 sk->sk_state_change(sk); 995 996 if (sock_type_connectible(sk->sk_type)) { 997 sock_reset_flag(sk, SOCK_DONE); 998 vsock_send_shutdown(sk, mode); 999 } 1000 } 1001 1002 out: 1003 release_sock(sk); 1004 return err; 1005 } 1006 1007 static __poll_t vsock_poll(struct file *file, struct socket *sock, 1008 poll_table *wait) 1009 { 1010 struct sock *sk; 1011 __poll_t mask; 1012 struct vsock_sock *vsk; 1013 1014 sk = sock->sk; 1015 vsk = vsock_sk(sk); 1016 1017 poll_wait(file, sk_sleep(sk), wait); 1018 mask = 0; 1019 1020 if (sk->sk_err) 1021 /* Signify that there has been an error on this socket. */ 1022 mask |= EPOLLERR; 1023 1024 /* INET sockets treat local write shutdown and peer write shutdown as a 1025 * case of EPOLLHUP set. 1026 */ 1027 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 1028 ((sk->sk_shutdown & SEND_SHUTDOWN) && 1029 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 1030 mask |= EPOLLHUP; 1031 } 1032 1033 if (sk->sk_shutdown & RCV_SHUTDOWN || 1034 vsk->peer_shutdown & SEND_SHUTDOWN) { 1035 mask |= EPOLLRDHUP; 1036 } 1037 1038 if (sock->type == SOCK_DGRAM) { 1039 /* For datagram sockets we can read if there is something in 1040 * the queue and write as long as the socket isn't shutdown for 1041 * sending. 1042 */ 1043 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 1044 (sk->sk_shutdown & RCV_SHUTDOWN)) { 1045 mask |= EPOLLIN | EPOLLRDNORM; 1046 } 1047 1048 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1049 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 1050 1051 } else if (sock_type_connectible(sk->sk_type)) { 1052 const struct vsock_transport *transport; 1053 1054 lock_sock(sk); 1055 1056 transport = vsk->transport; 1057 1058 /* Listening sockets that have connections in their accept 1059 * queue can be read. 1060 */ 1061 if (sk->sk_state == TCP_LISTEN 1062 && !vsock_is_accept_queue_empty(sk)) 1063 mask |= EPOLLIN | EPOLLRDNORM; 1064 1065 /* If there is something in the queue then we can read. */ 1066 if (transport && transport->stream_is_active(vsk) && 1067 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1068 bool data_ready_now = false; 1069 int target = sock_rcvlowat(sk, 0, INT_MAX); 1070 int ret = transport->notify_poll_in( 1071 vsk, target, &data_ready_now); 1072 if (ret < 0) { 1073 mask |= EPOLLERR; 1074 } else { 1075 if (data_ready_now) 1076 mask |= EPOLLIN | EPOLLRDNORM; 1077 1078 } 1079 } 1080 1081 /* Sockets whose connections have been closed, reset, or 1082 * terminated should also be considered read, and we check the 1083 * shutdown flag for that. 1084 */ 1085 if (sk->sk_shutdown & RCV_SHUTDOWN || 1086 vsk->peer_shutdown & SEND_SHUTDOWN) { 1087 mask |= EPOLLIN | EPOLLRDNORM; 1088 } 1089 1090 /* Connected sockets that can produce data can be written. */ 1091 if (transport && sk->sk_state == TCP_ESTABLISHED) { 1092 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1093 bool space_avail_now = false; 1094 int ret = transport->notify_poll_out( 1095 vsk, 1, &space_avail_now); 1096 if (ret < 0) { 1097 mask |= EPOLLERR; 1098 } else { 1099 if (space_avail_now) 1100 /* Remove EPOLLWRBAND since INET 1101 * sockets are not setting it. 1102 */ 1103 mask |= EPOLLOUT | EPOLLWRNORM; 1104 1105 } 1106 } 1107 } 1108 1109 /* Simulate INET socket poll behaviors, which sets 1110 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 1111 * but local send is not shutdown. 1112 */ 1113 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 1114 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1115 mask |= EPOLLOUT | EPOLLWRNORM; 1116 1117 } 1118 1119 release_sock(sk); 1120 } 1121 1122 return mask; 1123 } 1124 1125 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 1126 size_t len) 1127 { 1128 int err; 1129 struct sock *sk; 1130 struct vsock_sock *vsk; 1131 struct sockaddr_vm *remote_addr; 1132 const struct vsock_transport *transport; 1133 1134 if (msg->msg_flags & MSG_OOB) 1135 return -EOPNOTSUPP; 1136 1137 /* For now, MSG_DONTWAIT is always assumed... */ 1138 err = 0; 1139 sk = sock->sk; 1140 vsk = vsock_sk(sk); 1141 1142 lock_sock(sk); 1143 1144 transport = vsk->transport; 1145 1146 err = vsock_auto_bind(vsk); 1147 if (err) 1148 goto out; 1149 1150 1151 /* If the provided message contains an address, use that. Otherwise 1152 * fall back on the socket's remote handle (if it has been connected). 1153 */ 1154 if (msg->msg_name && 1155 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 1156 &remote_addr) == 0) { 1157 /* Ensure this address is of the right type and is a valid 1158 * destination. 1159 */ 1160 1161 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1162 remote_addr->svm_cid = transport->get_local_cid(); 1163 1164 if (!vsock_addr_bound(remote_addr)) { 1165 err = -EINVAL; 1166 goto out; 1167 } 1168 } else if (sock->state == SS_CONNECTED) { 1169 remote_addr = &vsk->remote_addr; 1170 1171 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1172 remote_addr->svm_cid = transport->get_local_cid(); 1173 1174 /* XXX Should connect() or this function ensure remote_addr is 1175 * bound? 1176 */ 1177 if (!vsock_addr_bound(&vsk->remote_addr)) { 1178 err = -EINVAL; 1179 goto out; 1180 } 1181 } else { 1182 err = -EINVAL; 1183 goto out; 1184 } 1185 1186 if (!transport->dgram_allow(remote_addr->svm_cid, 1187 remote_addr->svm_port)) { 1188 err = -EINVAL; 1189 goto out; 1190 } 1191 1192 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1193 1194 out: 1195 release_sock(sk); 1196 return err; 1197 } 1198 1199 static int vsock_dgram_connect(struct socket *sock, 1200 struct sockaddr *addr, int addr_len, int flags) 1201 { 1202 int err; 1203 struct sock *sk; 1204 struct vsock_sock *vsk; 1205 struct sockaddr_vm *remote_addr; 1206 1207 sk = sock->sk; 1208 vsk = vsock_sk(sk); 1209 1210 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1211 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1212 lock_sock(sk); 1213 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1214 VMADDR_PORT_ANY); 1215 sock->state = SS_UNCONNECTED; 1216 release_sock(sk); 1217 return 0; 1218 } else if (err != 0) 1219 return -EINVAL; 1220 1221 lock_sock(sk); 1222 1223 err = vsock_auto_bind(vsk); 1224 if (err) 1225 goto out; 1226 1227 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1228 remote_addr->svm_port)) { 1229 err = -EINVAL; 1230 goto out; 1231 } 1232 1233 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1234 sock->state = SS_CONNECTED; 1235 1236 out: 1237 release_sock(sk); 1238 return err; 1239 } 1240 1241 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1242 size_t len, int flags) 1243 { 1244 struct vsock_sock *vsk = vsock_sk(sock->sk); 1245 1246 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1247 } 1248 1249 static const struct proto_ops vsock_dgram_ops = { 1250 .family = PF_VSOCK, 1251 .owner = THIS_MODULE, 1252 .release = vsock_release, 1253 .bind = vsock_bind, 1254 .connect = vsock_dgram_connect, 1255 .socketpair = sock_no_socketpair, 1256 .accept = sock_no_accept, 1257 .getname = vsock_getname, 1258 .poll = vsock_poll, 1259 .ioctl = sock_no_ioctl, 1260 .listen = sock_no_listen, 1261 .shutdown = vsock_shutdown, 1262 .sendmsg = vsock_dgram_sendmsg, 1263 .recvmsg = vsock_dgram_recvmsg, 1264 .mmap = sock_no_mmap, 1265 .sendpage = sock_no_sendpage, 1266 }; 1267 1268 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1269 { 1270 const struct vsock_transport *transport = vsk->transport; 1271 1272 if (!transport || !transport->cancel_pkt) 1273 return -EOPNOTSUPP; 1274 1275 return transport->cancel_pkt(vsk); 1276 } 1277 1278 static void vsock_connect_timeout(struct work_struct *work) 1279 { 1280 struct sock *sk; 1281 struct vsock_sock *vsk; 1282 1283 vsk = container_of(work, struct vsock_sock, connect_work.work); 1284 sk = sk_vsock(vsk); 1285 1286 lock_sock(sk); 1287 if (sk->sk_state == TCP_SYN_SENT && 1288 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1289 sk->sk_state = TCP_CLOSE; 1290 sk->sk_socket->state = SS_UNCONNECTED; 1291 sk->sk_err = ETIMEDOUT; 1292 sk_error_report(sk); 1293 vsock_transport_cancel_pkt(vsk); 1294 } 1295 release_sock(sk); 1296 1297 sock_put(sk); 1298 } 1299 1300 static int vsock_connect(struct socket *sock, struct sockaddr *addr, 1301 int addr_len, int flags) 1302 { 1303 int err; 1304 struct sock *sk; 1305 struct vsock_sock *vsk; 1306 const struct vsock_transport *transport; 1307 struct sockaddr_vm *remote_addr; 1308 long timeout; 1309 DEFINE_WAIT(wait); 1310 1311 err = 0; 1312 sk = sock->sk; 1313 vsk = vsock_sk(sk); 1314 1315 lock_sock(sk); 1316 1317 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1318 switch (sock->state) { 1319 case SS_CONNECTED: 1320 err = -EISCONN; 1321 goto out; 1322 case SS_DISCONNECTING: 1323 err = -EINVAL; 1324 goto out; 1325 case SS_CONNECTING: 1326 /* This continues on so we can move sock into the SS_CONNECTED 1327 * state once the connection has completed (at which point err 1328 * will be set to zero also). Otherwise, we will either wait 1329 * for the connection or return -EALREADY should this be a 1330 * non-blocking call. 1331 */ 1332 err = -EALREADY; 1333 if (flags & O_NONBLOCK) 1334 goto out; 1335 break; 1336 default: 1337 if ((sk->sk_state == TCP_LISTEN) || 1338 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1339 err = -EINVAL; 1340 goto out; 1341 } 1342 1343 /* Set the remote address that we are connecting to. */ 1344 memcpy(&vsk->remote_addr, remote_addr, 1345 sizeof(vsk->remote_addr)); 1346 1347 err = vsock_assign_transport(vsk, NULL); 1348 if (err) 1349 goto out; 1350 1351 transport = vsk->transport; 1352 1353 /* The hypervisor and well-known contexts do not have socket 1354 * endpoints. 1355 */ 1356 if (!transport || 1357 !transport->stream_allow(remote_addr->svm_cid, 1358 remote_addr->svm_port)) { 1359 err = -ENETUNREACH; 1360 goto out; 1361 } 1362 1363 err = vsock_auto_bind(vsk); 1364 if (err) 1365 goto out; 1366 1367 sk->sk_state = TCP_SYN_SENT; 1368 1369 err = transport->connect(vsk); 1370 if (err < 0) 1371 goto out; 1372 1373 /* Mark sock as connecting and set the error code to in 1374 * progress in case this is a non-blocking connect. 1375 */ 1376 sock->state = SS_CONNECTING; 1377 err = -EINPROGRESS; 1378 } 1379 1380 /* The receive path will handle all communication until we are able to 1381 * enter the connected state. Here we wait for the connection to be 1382 * completed or a notification of an error. 1383 */ 1384 timeout = vsk->connect_timeout; 1385 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1386 1387 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1388 if (flags & O_NONBLOCK) { 1389 /* If we're not going to block, we schedule a timeout 1390 * function to generate a timeout on the connection 1391 * attempt, in case the peer doesn't respond in a 1392 * timely manner. We hold on to the socket until the 1393 * timeout fires. 1394 */ 1395 sock_hold(sk); 1396 1397 /* If the timeout function is already scheduled, 1398 * reschedule it, then ungrab the socket refcount to 1399 * keep it balanced. 1400 */ 1401 if (mod_delayed_work(system_wq, &vsk->connect_work, 1402 timeout)) 1403 sock_put(sk); 1404 1405 /* Skip ahead to preserve error code set above. */ 1406 goto out_wait; 1407 } 1408 1409 release_sock(sk); 1410 timeout = schedule_timeout(timeout); 1411 lock_sock(sk); 1412 1413 if (signal_pending(current)) { 1414 err = sock_intr_errno(timeout); 1415 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; 1416 sock->state = SS_UNCONNECTED; 1417 vsock_transport_cancel_pkt(vsk); 1418 vsock_remove_connected(vsk); 1419 goto out_wait; 1420 } else if (timeout == 0) { 1421 err = -ETIMEDOUT; 1422 sk->sk_state = TCP_CLOSE; 1423 sock->state = SS_UNCONNECTED; 1424 vsock_transport_cancel_pkt(vsk); 1425 goto out_wait; 1426 } 1427 1428 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1429 } 1430 1431 if (sk->sk_err) { 1432 err = -sk->sk_err; 1433 sk->sk_state = TCP_CLOSE; 1434 sock->state = SS_UNCONNECTED; 1435 } else { 1436 err = 0; 1437 } 1438 1439 out_wait: 1440 finish_wait(sk_sleep(sk), &wait); 1441 out: 1442 release_sock(sk); 1443 return err; 1444 } 1445 1446 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1447 bool kern) 1448 { 1449 struct sock *listener; 1450 int err; 1451 struct sock *connected; 1452 struct vsock_sock *vconnected; 1453 long timeout; 1454 DEFINE_WAIT(wait); 1455 1456 err = 0; 1457 listener = sock->sk; 1458 1459 lock_sock(listener); 1460 1461 if (!sock_type_connectible(sock->type)) { 1462 err = -EOPNOTSUPP; 1463 goto out; 1464 } 1465 1466 if (listener->sk_state != TCP_LISTEN) { 1467 err = -EINVAL; 1468 goto out; 1469 } 1470 1471 /* Wait for children sockets to appear; these are the new sockets 1472 * created upon connection establishment. 1473 */ 1474 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1475 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1476 1477 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1478 listener->sk_err == 0) { 1479 release_sock(listener); 1480 timeout = schedule_timeout(timeout); 1481 finish_wait(sk_sleep(listener), &wait); 1482 lock_sock(listener); 1483 1484 if (signal_pending(current)) { 1485 err = sock_intr_errno(timeout); 1486 goto out; 1487 } else if (timeout == 0) { 1488 err = -EAGAIN; 1489 goto out; 1490 } 1491 1492 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1493 } 1494 finish_wait(sk_sleep(listener), &wait); 1495 1496 if (listener->sk_err) 1497 err = -listener->sk_err; 1498 1499 if (connected) { 1500 sk_acceptq_removed(listener); 1501 1502 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1503 vconnected = vsock_sk(connected); 1504 1505 /* If the listener socket has received an error, then we should 1506 * reject this socket and return. Note that we simply mark the 1507 * socket rejected, drop our reference, and let the cleanup 1508 * function handle the cleanup; the fact that we found it in 1509 * the listener's accept queue guarantees that the cleanup 1510 * function hasn't run yet. 1511 */ 1512 if (err) { 1513 vconnected->rejected = true; 1514 } else { 1515 newsock->state = SS_CONNECTED; 1516 sock_graft(connected, newsock); 1517 } 1518 1519 release_sock(connected); 1520 sock_put(connected); 1521 } 1522 1523 out: 1524 release_sock(listener); 1525 return err; 1526 } 1527 1528 static int vsock_listen(struct socket *sock, int backlog) 1529 { 1530 int err; 1531 struct sock *sk; 1532 struct vsock_sock *vsk; 1533 1534 sk = sock->sk; 1535 1536 lock_sock(sk); 1537 1538 if (!sock_type_connectible(sk->sk_type)) { 1539 err = -EOPNOTSUPP; 1540 goto out; 1541 } 1542 1543 if (sock->state != SS_UNCONNECTED) { 1544 err = -EINVAL; 1545 goto out; 1546 } 1547 1548 vsk = vsock_sk(sk); 1549 1550 if (!vsock_addr_bound(&vsk->local_addr)) { 1551 err = -EINVAL; 1552 goto out; 1553 } 1554 1555 sk->sk_max_ack_backlog = backlog; 1556 sk->sk_state = TCP_LISTEN; 1557 1558 err = 0; 1559 1560 out: 1561 release_sock(sk); 1562 return err; 1563 } 1564 1565 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1566 const struct vsock_transport *transport, 1567 u64 val) 1568 { 1569 if (val > vsk->buffer_max_size) 1570 val = vsk->buffer_max_size; 1571 1572 if (val < vsk->buffer_min_size) 1573 val = vsk->buffer_min_size; 1574 1575 if (val != vsk->buffer_size && 1576 transport && transport->notify_buffer_size) 1577 transport->notify_buffer_size(vsk, &val); 1578 1579 vsk->buffer_size = val; 1580 } 1581 1582 static int vsock_connectible_setsockopt(struct socket *sock, 1583 int level, 1584 int optname, 1585 sockptr_t optval, 1586 unsigned int optlen) 1587 { 1588 int err; 1589 struct sock *sk; 1590 struct vsock_sock *vsk; 1591 const struct vsock_transport *transport; 1592 u64 val; 1593 1594 if (level != AF_VSOCK) 1595 return -ENOPROTOOPT; 1596 1597 #define COPY_IN(_v) \ 1598 do { \ 1599 if (optlen < sizeof(_v)) { \ 1600 err = -EINVAL; \ 1601 goto exit; \ 1602 } \ 1603 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1604 err = -EFAULT; \ 1605 goto exit; \ 1606 } \ 1607 } while (0) 1608 1609 err = 0; 1610 sk = sock->sk; 1611 vsk = vsock_sk(sk); 1612 1613 lock_sock(sk); 1614 1615 transport = vsk->transport; 1616 1617 switch (optname) { 1618 case SO_VM_SOCKETS_BUFFER_SIZE: 1619 COPY_IN(val); 1620 vsock_update_buffer_size(vsk, transport, val); 1621 break; 1622 1623 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1624 COPY_IN(val); 1625 vsk->buffer_max_size = val; 1626 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1627 break; 1628 1629 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1630 COPY_IN(val); 1631 vsk->buffer_min_size = val; 1632 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1633 break; 1634 1635 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1636 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: { 1637 struct __kernel_sock_timeval tv; 1638 1639 err = sock_copy_user_timeval(&tv, optval, optlen, 1640 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1641 if (err) 1642 break; 1643 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1644 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1645 vsk->connect_timeout = tv.tv_sec * HZ + 1646 DIV_ROUND_UP((unsigned long)tv.tv_usec, (USEC_PER_SEC / HZ)); 1647 if (vsk->connect_timeout == 0) 1648 vsk->connect_timeout = 1649 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1650 1651 } else { 1652 err = -ERANGE; 1653 } 1654 break; 1655 } 1656 1657 default: 1658 err = -ENOPROTOOPT; 1659 break; 1660 } 1661 1662 #undef COPY_IN 1663 1664 exit: 1665 release_sock(sk); 1666 return err; 1667 } 1668 1669 static int vsock_connectible_getsockopt(struct socket *sock, 1670 int level, int optname, 1671 char __user *optval, 1672 int __user *optlen) 1673 { 1674 struct sock *sk = sock->sk; 1675 struct vsock_sock *vsk = vsock_sk(sk); 1676 1677 union { 1678 u64 val64; 1679 struct old_timeval32 tm32; 1680 struct __kernel_old_timeval tm; 1681 struct __kernel_sock_timeval stm; 1682 } v; 1683 1684 int lv = sizeof(v.val64); 1685 int len; 1686 1687 if (level != AF_VSOCK) 1688 return -ENOPROTOOPT; 1689 1690 if (get_user(len, optlen)) 1691 return -EFAULT; 1692 1693 memset(&v, 0, sizeof(v)); 1694 1695 switch (optname) { 1696 case SO_VM_SOCKETS_BUFFER_SIZE: 1697 v.val64 = vsk->buffer_size; 1698 break; 1699 1700 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1701 v.val64 = vsk->buffer_max_size; 1702 break; 1703 1704 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1705 v.val64 = vsk->buffer_min_size; 1706 break; 1707 1708 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1709 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: 1710 lv = sock_get_timeout(vsk->connect_timeout, &v, 1711 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1712 break; 1713 1714 default: 1715 return -ENOPROTOOPT; 1716 } 1717 1718 if (len < lv) 1719 return -EINVAL; 1720 if (len > lv) 1721 len = lv; 1722 if (copy_to_user(optval, &v, len)) 1723 return -EFAULT; 1724 1725 if (put_user(len, optlen)) 1726 return -EFAULT; 1727 1728 return 0; 1729 } 1730 1731 static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, 1732 size_t len) 1733 { 1734 struct sock *sk; 1735 struct vsock_sock *vsk; 1736 const struct vsock_transport *transport; 1737 ssize_t total_written; 1738 long timeout; 1739 int err; 1740 struct vsock_transport_send_notify_data send_data; 1741 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1742 1743 sk = sock->sk; 1744 vsk = vsock_sk(sk); 1745 total_written = 0; 1746 err = 0; 1747 1748 if (msg->msg_flags & MSG_OOB) 1749 return -EOPNOTSUPP; 1750 1751 lock_sock(sk); 1752 1753 transport = vsk->transport; 1754 1755 /* Callers should not provide a destination with connection oriented 1756 * sockets. 1757 */ 1758 if (msg->msg_namelen) { 1759 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1760 goto out; 1761 } 1762 1763 /* Send data only if both sides are not shutdown in the direction. */ 1764 if (sk->sk_shutdown & SEND_SHUTDOWN || 1765 vsk->peer_shutdown & RCV_SHUTDOWN) { 1766 err = -EPIPE; 1767 goto out; 1768 } 1769 1770 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1771 !vsock_addr_bound(&vsk->local_addr)) { 1772 err = -ENOTCONN; 1773 goto out; 1774 } 1775 1776 if (!vsock_addr_bound(&vsk->remote_addr)) { 1777 err = -EDESTADDRREQ; 1778 goto out; 1779 } 1780 1781 /* Wait for room in the produce queue to enqueue our user's data. */ 1782 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1783 1784 err = transport->notify_send_init(vsk, &send_data); 1785 if (err < 0) 1786 goto out; 1787 1788 while (total_written < len) { 1789 ssize_t written; 1790 1791 add_wait_queue(sk_sleep(sk), &wait); 1792 while (vsock_stream_has_space(vsk) == 0 && 1793 sk->sk_err == 0 && 1794 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1795 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1796 1797 /* Don't wait for non-blocking sockets. */ 1798 if (timeout == 0) { 1799 err = -EAGAIN; 1800 remove_wait_queue(sk_sleep(sk), &wait); 1801 goto out_err; 1802 } 1803 1804 err = transport->notify_send_pre_block(vsk, &send_data); 1805 if (err < 0) { 1806 remove_wait_queue(sk_sleep(sk), &wait); 1807 goto out_err; 1808 } 1809 1810 release_sock(sk); 1811 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1812 lock_sock(sk); 1813 if (signal_pending(current)) { 1814 err = sock_intr_errno(timeout); 1815 remove_wait_queue(sk_sleep(sk), &wait); 1816 goto out_err; 1817 } else if (timeout == 0) { 1818 err = -EAGAIN; 1819 remove_wait_queue(sk_sleep(sk), &wait); 1820 goto out_err; 1821 } 1822 } 1823 remove_wait_queue(sk_sleep(sk), &wait); 1824 1825 /* These checks occur both as part of and after the loop 1826 * conditional since we need to check before and after 1827 * sleeping. 1828 */ 1829 if (sk->sk_err) { 1830 err = -sk->sk_err; 1831 goto out_err; 1832 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1833 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1834 err = -EPIPE; 1835 goto out_err; 1836 } 1837 1838 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1839 if (err < 0) 1840 goto out_err; 1841 1842 /* Note that enqueue will only write as many bytes as are free 1843 * in the produce queue, so we don't need to ensure len is 1844 * smaller than the queue size. It is the caller's 1845 * responsibility to check how many bytes we were able to send. 1846 */ 1847 1848 if (sk->sk_type == SOCK_SEQPACKET) { 1849 written = transport->seqpacket_enqueue(vsk, 1850 msg, len - total_written); 1851 } else { 1852 written = transport->stream_enqueue(vsk, 1853 msg, len - total_written); 1854 } 1855 if (written < 0) { 1856 err = -ENOMEM; 1857 goto out_err; 1858 } 1859 1860 total_written += written; 1861 1862 err = transport->notify_send_post_enqueue( 1863 vsk, written, &send_data); 1864 if (err < 0) 1865 goto out_err; 1866 1867 } 1868 1869 out_err: 1870 if (total_written > 0) { 1871 /* Return number of written bytes only if: 1872 * 1) SOCK_STREAM socket. 1873 * 2) SOCK_SEQPACKET socket when whole buffer is sent. 1874 */ 1875 if (sk->sk_type == SOCK_STREAM || total_written == len) 1876 err = total_written; 1877 } 1878 out: 1879 release_sock(sk); 1880 return err; 1881 } 1882 1883 static int vsock_connectible_wait_data(struct sock *sk, 1884 struct wait_queue_entry *wait, 1885 long timeout, 1886 struct vsock_transport_recv_notify_data *recv_data, 1887 size_t target) 1888 { 1889 const struct vsock_transport *transport; 1890 struct vsock_sock *vsk; 1891 s64 data; 1892 int err; 1893 1894 vsk = vsock_sk(sk); 1895 err = 0; 1896 transport = vsk->transport; 1897 1898 while ((data = vsock_connectible_has_data(vsk)) == 0) { 1899 prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); 1900 1901 if (sk->sk_err != 0 || 1902 (sk->sk_shutdown & RCV_SHUTDOWN) || 1903 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1904 break; 1905 } 1906 1907 /* Don't wait for non-blocking sockets. */ 1908 if (timeout == 0) { 1909 err = -EAGAIN; 1910 break; 1911 } 1912 1913 if (recv_data) { 1914 err = transport->notify_recv_pre_block(vsk, target, recv_data); 1915 if (err < 0) 1916 break; 1917 } 1918 1919 release_sock(sk); 1920 timeout = schedule_timeout(timeout); 1921 lock_sock(sk); 1922 1923 if (signal_pending(current)) { 1924 err = sock_intr_errno(timeout); 1925 break; 1926 } else if (timeout == 0) { 1927 err = -EAGAIN; 1928 break; 1929 } 1930 } 1931 1932 finish_wait(sk_sleep(sk), wait); 1933 1934 if (err) 1935 return err; 1936 1937 /* Internal transport error when checking for available 1938 * data. XXX This should be changed to a connection 1939 * reset in a later change. 1940 */ 1941 if (data < 0) 1942 return -ENOMEM; 1943 1944 return data; 1945 } 1946 1947 static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, 1948 size_t len, int flags) 1949 { 1950 struct vsock_transport_recv_notify_data recv_data; 1951 const struct vsock_transport *transport; 1952 struct vsock_sock *vsk; 1953 ssize_t copied; 1954 size_t target; 1955 long timeout; 1956 int err; 1957 1958 DEFINE_WAIT(wait); 1959 1960 vsk = vsock_sk(sk); 1961 transport = vsk->transport; 1962 1963 /* We must not copy less than target bytes into the user's buffer 1964 * before returning successfully, so we wait for the consume queue to 1965 * have that much data to consume before dequeueing. Note that this 1966 * makes it impossible to handle cases where target is greater than the 1967 * queue size. 1968 */ 1969 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1970 if (target >= transport->stream_rcvhiwat(vsk)) { 1971 err = -ENOMEM; 1972 goto out; 1973 } 1974 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1975 copied = 0; 1976 1977 err = transport->notify_recv_init(vsk, target, &recv_data); 1978 if (err < 0) 1979 goto out; 1980 1981 1982 while (1) { 1983 ssize_t read; 1984 1985 err = vsock_connectible_wait_data(sk, &wait, timeout, 1986 &recv_data, target); 1987 if (err <= 0) 1988 break; 1989 1990 err = transport->notify_recv_pre_dequeue(vsk, target, 1991 &recv_data); 1992 if (err < 0) 1993 break; 1994 1995 read = transport->stream_dequeue(vsk, msg, len - copied, flags); 1996 if (read < 0) { 1997 err = -ENOMEM; 1998 break; 1999 } 2000 2001 copied += read; 2002 2003 err = transport->notify_recv_post_dequeue(vsk, target, read, 2004 !(flags & MSG_PEEK), &recv_data); 2005 if (err < 0) 2006 goto out; 2007 2008 if (read >= target || flags & MSG_PEEK) 2009 break; 2010 2011 target -= read; 2012 } 2013 2014 if (sk->sk_err) 2015 err = -sk->sk_err; 2016 else if (sk->sk_shutdown & RCV_SHUTDOWN) 2017 err = 0; 2018 2019 if (copied > 0) 2020 err = copied; 2021 2022 out: 2023 return err; 2024 } 2025 2026 static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, 2027 size_t len, int flags) 2028 { 2029 const struct vsock_transport *transport; 2030 struct vsock_sock *vsk; 2031 ssize_t msg_len; 2032 long timeout; 2033 int err = 0; 2034 DEFINE_WAIT(wait); 2035 2036 vsk = vsock_sk(sk); 2037 transport = vsk->transport; 2038 2039 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2040 2041 err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0); 2042 if (err <= 0) 2043 goto out; 2044 2045 msg_len = transport->seqpacket_dequeue(vsk, msg, flags); 2046 2047 if (msg_len < 0) { 2048 err = -ENOMEM; 2049 goto out; 2050 } 2051 2052 if (sk->sk_err) { 2053 err = -sk->sk_err; 2054 } else if (sk->sk_shutdown & RCV_SHUTDOWN) { 2055 err = 0; 2056 } else { 2057 /* User sets MSG_TRUNC, so return real length of 2058 * packet. 2059 */ 2060 if (flags & MSG_TRUNC) 2061 err = msg_len; 2062 else 2063 err = len - msg_data_left(msg); 2064 2065 /* Always set MSG_TRUNC if real length of packet is 2066 * bigger than user's buffer. 2067 */ 2068 if (msg_len > len) 2069 msg->msg_flags |= MSG_TRUNC; 2070 } 2071 2072 out: 2073 return err; 2074 } 2075 2076 static int 2077 vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2078 int flags) 2079 { 2080 struct sock *sk; 2081 struct vsock_sock *vsk; 2082 const struct vsock_transport *transport; 2083 int err; 2084 2085 DEFINE_WAIT(wait); 2086 2087 sk = sock->sk; 2088 vsk = vsock_sk(sk); 2089 err = 0; 2090 2091 lock_sock(sk); 2092 2093 transport = vsk->transport; 2094 2095 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 2096 /* Recvmsg is supposed to return 0 if a peer performs an 2097 * orderly shutdown. Differentiate between that case and when a 2098 * peer has not connected or a local shutdown occurred with the 2099 * SOCK_DONE flag. 2100 */ 2101 if (sock_flag(sk, SOCK_DONE)) 2102 err = 0; 2103 else 2104 err = -ENOTCONN; 2105 2106 goto out; 2107 } 2108 2109 if (flags & MSG_OOB) { 2110 err = -EOPNOTSUPP; 2111 goto out; 2112 } 2113 2114 /* We don't check peer_shutdown flag here since peer may actually shut 2115 * down, but there can be data in the queue that a local socket can 2116 * receive. 2117 */ 2118 if (sk->sk_shutdown & RCV_SHUTDOWN) { 2119 err = 0; 2120 goto out; 2121 } 2122 2123 /* It is valid on Linux to pass in a zero-length receive buffer. This 2124 * is not an error. We may as well bail out now. 2125 */ 2126 if (!len) { 2127 err = 0; 2128 goto out; 2129 } 2130 2131 if (sk->sk_type == SOCK_STREAM) 2132 err = __vsock_stream_recvmsg(sk, msg, len, flags); 2133 else 2134 err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); 2135 2136 out: 2137 release_sock(sk); 2138 return err; 2139 } 2140 2141 static int vsock_set_rcvlowat(struct sock *sk, int val) 2142 { 2143 const struct vsock_transport *transport; 2144 struct vsock_sock *vsk; 2145 2146 vsk = vsock_sk(sk); 2147 2148 if (val > vsk->buffer_size) 2149 return -EINVAL; 2150 2151 transport = vsk->transport; 2152 2153 if (transport && transport->set_rcvlowat) 2154 return transport->set_rcvlowat(vsk, val); 2155 2156 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 2157 return 0; 2158 } 2159 2160 static const struct proto_ops vsock_stream_ops = { 2161 .family = PF_VSOCK, 2162 .owner = THIS_MODULE, 2163 .release = vsock_release, 2164 .bind = vsock_bind, 2165 .connect = vsock_connect, 2166 .socketpair = sock_no_socketpair, 2167 .accept = vsock_accept, 2168 .getname = vsock_getname, 2169 .poll = vsock_poll, 2170 .ioctl = sock_no_ioctl, 2171 .listen = vsock_listen, 2172 .shutdown = vsock_shutdown, 2173 .setsockopt = vsock_connectible_setsockopt, 2174 .getsockopt = vsock_connectible_getsockopt, 2175 .sendmsg = vsock_connectible_sendmsg, 2176 .recvmsg = vsock_connectible_recvmsg, 2177 .mmap = sock_no_mmap, 2178 .sendpage = sock_no_sendpage, 2179 .set_rcvlowat = vsock_set_rcvlowat, 2180 }; 2181 2182 static const struct proto_ops vsock_seqpacket_ops = { 2183 .family = PF_VSOCK, 2184 .owner = THIS_MODULE, 2185 .release = vsock_release, 2186 .bind = vsock_bind, 2187 .connect = vsock_connect, 2188 .socketpair = sock_no_socketpair, 2189 .accept = vsock_accept, 2190 .getname = vsock_getname, 2191 .poll = vsock_poll, 2192 .ioctl = sock_no_ioctl, 2193 .listen = vsock_listen, 2194 .shutdown = vsock_shutdown, 2195 .setsockopt = vsock_connectible_setsockopt, 2196 .getsockopt = vsock_connectible_getsockopt, 2197 .sendmsg = vsock_connectible_sendmsg, 2198 .recvmsg = vsock_connectible_recvmsg, 2199 .mmap = sock_no_mmap, 2200 .sendpage = sock_no_sendpage, 2201 }; 2202 2203 static int vsock_create(struct net *net, struct socket *sock, 2204 int protocol, int kern) 2205 { 2206 struct vsock_sock *vsk; 2207 struct sock *sk; 2208 int ret; 2209 2210 if (!sock) 2211 return -EINVAL; 2212 2213 if (protocol && protocol != PF_VSOCK) 2214 return -EPROTONOSUPPORT; 2215 2216 switch (sock->type) { 2217 case SOCK_DGRAM: 2218 sock->ops = &vsock_dgram_ops; 2219 break; 2220 case SOCK_STREAM: 2221 sock->ops = &vsock_stream_ops; 2222 break; 2223 case SOCK_SEQPACKET: 2224 sock->ops = &vsock_seqpacket_ops; 2225 break; 2226 default: 2227 return -ESOCKTNOSUPPORT; 2228 } 2229 2230 sock->state = SS_UNCONNECTED; 2231 2232 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2233 if (!sk) 2234 return -ENOMEM; 2235 2236 vsk = vsock_sk(sk); 2237 2238 if (sock->type == SOCK_DGRAM) { 2239 ret = vsock_assign_transport(vsk, NULL); 2240 if (ret < 0) { 2241 sock_put(sk); 2242 return ret; 2243 } 2244 } 2245 2246 vsock_insert_unbound(vsk); 2247 2248 return 0; 2249 } 2250 2251 static const struct net_proto_family vsock_family_ops = { 2252 .family = AF_VSOCK, 2253 .create = vsock_create, 2254 .owner = THIS_MODULE, 2255 }; 2256 2257 static long vsock_dev_do_ioctl(struct file *filp, 2258 unsigned int cmd, void __user *ptr) 2259 { 2260 u32 __user *p = ptr; 2261 u32 cid = VMADDR_CID_ANY; 2262 int retval = 0; 2263 2264 switch (cmd) { 2265 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2266 /* To be compatible with the VMCI behavior, we prioritize the 2267 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2268 */ 2269 if (transport_g2h) 2270 cid = transport_g2h->get_local_cid(); 2271 else if (transport_h2g) 2272 cid = transport_h2g->get_local_cid(); 2273 2274 if (put_user(cid, p) != 0) 2275 retval = -EFAULT; 2276 break; 2277 2278 default: 2279 retval = -ENOIOCTLCMD; 2280 } 2281 2282 return retval; 2283 } 2284 2285 static long vsock_dev_ioctl(struct file *filp, 2286 unsigned int cmd, unsigned long arg) 2287 { 2288 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2289 } 2290 2291 #ifdef CONFIG_COMPAT 2292 static long vsock_dev_compat_ioctl(struct file *filp, 2293 unsigned int cmd, unsigned long arg) 2294 { 2295 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2296 } 2297 #endif 2298 2299 static const struct file_operations vsock_device_ops = { 2300 .owner = THIS_MODULE, 2301 .unlocked_ioctl = vsock_dev_ioctl, 2302 #ifdef CONFIG_COMPAT 2303 .compat_ioctl = vsock_dev_compat_ioctl, 2304 #endif 2305 .open = nonseekable_open, 2306 }; 2307 2308 static struct miscdevice vsock_device = { 2309 .name = "vsock", 2310 .fops = &vsock_device_ops, 2311 }; 2312 2313 static int __init vsock_init(void) 2314 { 2315 int err = 0; 2316 2317 vsock_init_tables(); 2318 2319 vsock_proto.owner = THIS_MODULE; 2320 vsock_device.minor = MISC_DYNAMIC_MINOR; 2321 err = misc_register(&vsock_device); 2322 if (err) { 2323 pr_err("Failed to register misc device\n"); 2324 goto err_reset_transport; 2325 } 2326 2327 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2328 if (err) { 2329 pr_err("Cannot register vsock protocol\n"); 2330 goto err_deregister_misc; 2331 } 2332 2333 err = sock_register(&vsock_family_ops); 2334 if (err) { 2335 pr_err("could not register af_vsock (%d) address family: %d\n", 2336 AF_VSOCK, err); 2337 goto err_unregister_proto; 2338 } 2339 2340 return 0; 2341 2342 err_unregister_proto: 2343 proto_unregister(&vsock_proto); 2344 err_deregister_misc: 2345 misc_deregister(&vsock_device); 2346 err_reset_transport: 2347 return err; 2348 } 2349 2350 static void __exit vsock_exit(void) 2351 { 2352 misc_deregister(&vsock_device); 2353 sock_unregister(AF_VSOCK); 2354 proto_unregister(&vsock_proto); 2355 } 2356 2357 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2358 { 2359 return vsk->transport; 2360 } 2361 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2362 2363 int vsock_core_register(const struct vsock_transport *t, int features) 2364 { 2365 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2366 int err = mutex_lock_interruptible(&vsock_register_mutex); 2367 2368 if (err) 2369 return err; 2370 2371 t_h2g = transport_h2g; 2372 t_g2h = transport_g2h; 2373 t_dgram = transport_dgram; 2374 t_local = transport_local; 2375 2376 if (features & VSOCK_TRANSPORT_F_H2G) { 2377 if (t_h2g) { 2378 err = -EBUSY; 2379 goto err_busy; 2380 } 2381 t_h2g = t; 2382 } 2383 2384 if (features & VSOCK_TRANSPORT_F_G2H) { 2385 if (t_g2h) { 2386 err = -EBUSY; 2387 goto err_busy; 2388 } 2389 t_g2h = t; 2390 } 2391 2392 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2393 if (t_dgram) { 2394 err = -EBUSY; 2395 goto err_busy; 2396 } 2397 t_dgram = t; 2398 } 2399 2400 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2401 if (t_local) { 2402 err = -EBUSY; 2403 goto err_busy; 2404 } 2405 t_local = t; 2406 } 2407 2408 transport_h2g = t_h2g; 2409 transport_g2h = t_g2h; 2410 transport_dgram = t_dgram; 2411 transport_local = t_local; 2412 2413 err_busy: 2414 mutex_unlock(&vsock_register_mutex); 2415 return err; 2416 } 2417 EXPORT_SYMBOL_GPL(vsock_core_register); 2418 2419 void vsock_core_unregister(const struct vsock_transport *t) 2420 { 2421 mutex_lock(&vsock_register_mutex); 2422 2423 if (transport_h2g == t) 2424 transport_h2g = NULL; 2425 2426 if (transport_g2h == t) 2427 transport_g2h = NULL; 2428 2429 if (transport_dgram == t) 2430 transport_dgram = NULL; 2431 2432 if (transport_local == t) 2433 transport_local = NULL; 2434 2435 mutex_unlock(&vsock_register_mutex); 2436 } 2437 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2438 2439 module_init(vsock_init); 2440 module_exit(vsock_exit); 2441 2442 MODULE_AUTHOR("VMware, Inc."); 2443 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2444 MODULE_VERSION("1.0.2.0-k"); 2445 MODULE_LICENSE("GPL v2"); 2446