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 struct proto vsock_proto = { 120 .name = "AF_VSOCK", 121 .owner = THIS_MODULE, 122 .obj_size = sizeof(struct vsock_sock), 123 #ifdef CONFIG_BPF_SYSCALL 124 .psock_update_sk_prot = vsock_bpf_update_proto, 125 #endif 126 }; 127 128 /* The default peer timeout indicates how long we will wait for a peer response 129 * to a control message. 130 */ 131 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ) 132 133 #define VSOCK_DEFAULT_BUFFER_SIZE (1024 * 256) 134 #define VSOCK_DEFAULT_BUFFER_MAX_SIZE (1024 * 256) 135 #define VSOCK_DEFAULT_BUFFER_MIN_SIZE 128 136 137 /* Transport used for host->guest communication */ 138 static const struct vsock_transport *transport_h2g; 139 /* Transport used for guest->host communication */ 140 static const struct vsock_transport *transport_g2h; 141 /* Transport used for DGRAM communication */ 142 static const struct vsock_transport *transport_dgram; 143 /* Transport used for local communication */ 144 static const struct vsock_transport *transport_local; 145 static DEFINE_MUTEX(vsock_register_mutex); 146 147 /**** UTILS ****/ 148 149 /* Each bound VSocket is stored in the bind hash table and each connected 150 * VSocket is stored in the connected hash table. 151 * 152 * Unbound sockets are all put on the same list attached to the end of the hash 153 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in 154 * the bucket that their local address hashes to (vsock_bound_sockets(addr) 155 * represents the list that addr hashes to). 156 * 157 * Specifically, we initialize the vsock_bind_table array to a size of 158 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through 159 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and 160 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function 161 * mods with VSOCK_HASH_SIZE to ensure this. 162 */ 163 #define MAX_PORT_RETRIES 24 164 165 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE) 166 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)]) 167 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE]) 168 169 /* XXX This can probably be implemented in a better way. */ 170 #define VSOCK_CONN_HASH(src, dst) \ 171 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE) 172 #define vsock_connected_sockets(src, dst) \ 173 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)]) 174 #define vsock_connected_sockets_vsk(vsk) \ 175 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr) 176 177 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 178 EXPORT_SYMBOL_GPL(vsock_bind_table); 179 struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 180 EXPORT_SYMBOL_GPL(vsock_connected_table); 181 DEFINE_SPINLOCK(vsock_table_lock); 182 EXPORT_SYMBOL_GPL(vsock_table_lock); 183 184 /* Autobind this socket to the local address if necessary. */ 185 static int vsock_auto_bind(struct vsock_sock *vsk) 186 { 187 struct sock *sk = sk_vsock(vsk); 188 struct sockaddr_vm local_addr; 189 190 if (vsock_addr_bound(&vsk->local_addr)) 191 return 0; 192 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 193 return __vsock_bind(sk, &local_addr); 194 } 195 196 static void vsock_init_tables(void) 197 { 198 int i; 199 200 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++) 201 INIT_LIST_HEAD(&vsock_bind_table[i]); 202 203 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) 204 INIT_LIST_HEAD(&vsock_connected_table[i]); 205 } 206 207 static void __vsock_insert_bound(struct list_head *list, 208 struct vsock_sock *vsk) 209 { 210 sock_hold(&vsk->sk); 211 list_add(&vsk->bound_table, list); 212 } 213 214 static void __vsock_insert_connected(struct list_head *list, 215 struct vsock_sock *vsk) 216 { 217 sock_hold(&vsk->sk); 218 list_add(&vsk->connected_table, list); 219 } 220 221 static void __vsock_remove_bound(struct vsock_sock *vsk) 222 { 223 list_del_init(&vsk->bound_table); 224 sock_put(&vsk->sk); 225 } 226 227 static void __vsock_remove_connected(struct vsock_sock *vsk) 228 { 229 list_del_init(&vsk->connected_table); 230 sock_put(&vsk->sk); 231 } 232 233 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr) 234 { 235 struct vsock_sock *vsk; 236 237 list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) { 238 if (vsock_addr_equals_addr(addr, &vsk->local_addr)) 239 return sk_vsock(vsk); 240 241 if (addr->svm_port == vsk->local_addr.svm_port && 242 (vsk->local_addr.svm_cid == VMADDR_CID_ANY || 243 addr->svm_cid == VMADDR_CID_ANY)) 244 return sk_vsock(vsk); 245 } 246 247 return NULL; 248 } 249 250 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src, 251 struct sockaddr_vm *dst) 252 { 253 struct vsock_sock *vsk; 254 255 list_for_each_entry(vsk, vsock_connected_sockets(src, dst), 256 connected_table) { 257 if (vsock_addr_equals_addr(src, &vsk->remote_addr) && 258 dst->svm_port == vsk->local_addr.svm_port) { 259 return sk_vsock(vsk); 260 } 261 } 262 263 return NULL; 264 } 265 266 static void vsock_insert_unbound(struct vsock_sock *vsk) 267 { 268 spin_lock_bh(&vsock_table_lock); 269 __vsock_insert_bound(vsock_unbound_sockets, vsk); 270 spin_unlock_bh(&vsock_table_lock); 271 } 272 273 void vsock_insert_connected(struct vsock_sock *vsk) 274 { 275 struct list_head *list = vsock_connected_sockets( 276 &vsk->remote_addr, &vsk->local_addr); 277 278 spin_lock_bh(&vsock_table_lock); 279 __vsock_insert_connected(list, vsk); 280 spin_unlock_bh(&vsock_table_lock); 281 } 282 EXPORT_SYMBOL_GPL(vsock_insert_connected); 283 284 void vsock_remove_bound(struct vsock_sock *vsk) 285 { 286 spin_lock_bh(&vsock_table_lock); 287 if (__vsock_in_bound_table(vsk)) 288 __vsock_remove_bound(vsk); 289 spin_unlock_bh(&vsock_table_lock); 290 } 291 EXPORT_SYMBOL_GPL(vsock_remove_bound); 292 293 void vsock_remove_connected(struct vsock_sock *vsk) 294 { 295 spin_lock_bh(&vsock_table_lock); 296 if (__vsock_in_connected_table(vsk)) 297 __vsock_remove_connected(vsk); 298 spin_unlock_bh(&vsock_table_lock); 299 } 300 EXPORT_SYMBOL_GPL(vsock_remove_connected); 301 302 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr) 303 { 304 struct sock *sk; 305 306 spin_lock_bh(&vsock_table_lock); 307 sk = __vsock_find_bound_socket(addr); 308 if (sk) 309 sock_hold(sk); 310 311 spin_unlock_bh(&vsock_table_lock); 312 313 return sk; 314 } 315 EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 316 317 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, 318 struct sockaddr_vm *dst) 319 { 320 struct sock *sk; 321 322 spin_lock_bh(&vsock_table_lock); 323 sk = __vsock_find_connected_socket(src, dst); 324 if (sk) 325 sock_hold(sk); 326 327 spin_unlock_bh(&vsock_table_lock); 328 329 return sk; 330 } 331 EXPORT_SYMBOL_GPL(vsock_find_connected_socket); 332 333 void vsock_remove_sock(struct vsock_sock *vsk) 334 { 335 vsock_remove_bound(vsk); 336 vsock_remove_connected(vsk); 337 } 338 EXPORT_SYMBOL_GPL(vsock_remove_sock); 339 340 void vsock_for_each_connected_socket(struct vsock_transport *transport, 341 void (*fn)(struct sock *sk)) 342 { 343 int i; 344 345 spin_lock_bh(&vsock_table_lock); 346 347 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) { 348 struct vsock_sock *vsk; 349 list_for_each_entry(vsk, &vsock_connected_table[i], 350 connected_table) { 351 if (vsk->transport != transport) 352 continue; 353 354 fn(sk_vsock(vsk)); 355 } 356 } 357 358 spin_unlock_bh(&vsock_table_lock); 359 } 360 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket); 361 362 void vsock_add_pending(struct sock *listener, struct sock *pending) 363 { 364 struct vsock_sock *vlistener; 365 struct vsock_sock *vpending; 366 367 vlistener = vsock_sk(listener); 368 vpending = vsock_sk(pending); 369 370 sock_hold(pending); 371 sock_hold(listener); 372 list_add_tail(&vpending->pending_links, &vlistener->pending_links); 373 } 374 EXPORT_SYMBOL_GPL(vsock_add_pending); 375 376 void vsock_remove_pending(struct sock *listener, struct sock *pending) 377 { 378 struct vsock_sock *vpending = vsock_sk(pending); 379 380 list_del_init(&vpending->pending_links); 381 sock_put(listener); 382 sock_put(pending); 383 } 384 EXPORT_SYMBOL_GPL(vsock_remove_pending); 385 386 void vsock_enqueue_accept(struct sock *listener, struct sock *connected) 387 { 388 struct vsock_sock *vlistener; 389 struct vsock_sock *vconnected; 390 391 vlistener = vsock_sk(listener); 392 vconnected = vsock_sk(connected); 393 394 sock_hold(connected); 395 sock_hold(listener); 396 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue); 397 } 398 EXPORT_SYMBOL_GPL(vsock_enqueue_accept); 399 400 static bool vsock_use_local_transport(unsigned int remote_cid) 401 { 402 if (!transport_local) 403 return false; 404 405 if (remote_cid == VMADDR_CID_LOCAL) 406 return true; 407 408 if (transport_g2h) { 409 return remote_cid == transport_g2h->get_local_cid(); 410 } else { 411 return remote_cid == VMADDR_CID_HOST; 412 } 413 } 414 415 static void vsock_deassign_transport(struct vsock_sock *vsk) 416 { 417 if (!vsk->transport) 418 return; 419 420 vsk->transport->destruct(vsk); 421 module_put(vsk->transport->module); 422 vsk->transport = NULL; 423 } 424 425 /* Assign a transport to a socket and call the .init transport callback. 426 * 427 * Note: for connection oriented socket this must be called when vsk->remote_addr 428 * is set (e.g. during the connect() or when a connection request on a listener 429 * socket is received). 430 * The vsk->remote_addr is used to decide which transport to use: 431 * - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if 432 * g2h is not loaded, will use local transport; 433 * - remote CID <= VMADDR_CID_HOST or h2g is not loaded or remote flags field 434 * includes VMADDR_FLAG_TO_HOST flag value, will use guest->host transport; 435 * - remote CID > VMADDR_CID_HOST will use host->guest transport; 436 */ 437 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk) 438 { 439 const struct vsock_transport *new_transport; 440 struct sock *sk = sk_vsock(vsk); 441 unsigned int remote_cid = vsk->remote_addr.svm_cid; 442 __u8 remote_flags; 443 int ret; 444 445 /* If the packet is coming with the source and destination CIDs higher 446 * than VMADDR_CID_HOST, then a vsock channel where all the packets are 447 * forwarded to the host should be established. Then the host will 448 * need to forward the packets to the guest. 449 * 450 * The flag is set on the (listen) receive path (psk is not NULL). On 451 * the connect path the flag can be set by the user space application. 452 */ 453 if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST && 454 vsk->remote_addr.svm_cid > VMADDR_CID_HOST) 455 vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST; 456 457 remote_flags = vsk->remote_addr.svm_flags; 458 459 switch (sk->sk_type) { 460 case SOCK_DGRAM: 461 new_transport = transport_dgram; 462 break; 463 case SOCK_STREAM: 464 case SOCK_SEQPACKET: 465 if (vsock_use_local_transport(remote_cid)) 466 new_transport = transport_local; 467 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g || 468 (remote_flags & VMADDR_FLAG_TO_HOST)) 469 new_transport = transport_g2h; 470 else 471 new_transport = transport_h2g; 472 break; 473 default: 474 return -ESOCKTNOSUPPORT; 475 } 476 477 if (vsk->transport) { 478 if (vsk->transport == new_transport) 479 return 0; 480 481 /* transport->release() must be called with sock lock acquired. 482 * This path can only be taken during vsock_connect(), where we 483 * have already held the sock lock. In the other cases, this 484 * function is called on a new socket which is not assigned to 485 * any transport. 486 */ 487 vsk->transport->release(vsk); 488 vsock_deassign_transport(vsk); 489 } 490 491 /* We increase the module refcnt to prevent the transport unloading 492 * while there are open sockets assigned to it. 493 */ 494 if (!new_transport || !try_module_get(new_transport->module)) 495 return -ENODEV; 496 497 if (sk->sk_type == SOCK_SEQPACKET) { 498 if (!new_transport->seqpacket_allow || 499 !new_transport->seqpacket_allow(remote_cid)) { 500 module_put(new_transport->module); 501 return -ESOCKTNOSUPPORT; 502 } 503 } 504 505 ret = new_transport->init(vsk, psk); 506 if (ret) { 507 module_put(new_transport->module); 508 return ret; 509 } 510 511 vsk->transport = new_transport; 512 513 return 0; 514 } 515 EXPORT_SYMBOL_GPL(vsock_assign_transport); 516 517 bool vsock_find_cid(unsigned int cid) 518 { 519 if (transport_g2h && cid == transport_g2h->get_local_cid()) 520 return true; 521 522 if (transport_h2g && cid == VMADDR_CID_HOST) 523 return true; 524 525 if (transport_local && cid == VMADDR_CID_LOCAL) 526 return true; 527 528 return false; 529 } 530 EXPORT_SYMBOL_GPL(vsock_find_cid); 531 532 static struct sock *vsock_dequeue_accept(struct sock *listener) 533 { 534 struct vsock_sock *vlistener; 535 struct vsock_sock *vconnected; 536 537 vlistener = vsock_sk(listener); 538 539 if (list_empty(&vlistener->accept_queue)) 540 return NULL; 541 542 vconnected = list_entry(vlistener->accept_queue.next, 543 struct vsock_sock, accept_queue); 544 545 list_del_init(&vconnected->accept_queue); 546 sock_put(listener); 547 /* The caller will need a reference on the connected socket so we let 548 * it call sock_put(). 549 */ 550 551 return sk_vsock(vconnected); 552 } 553 554 static bool vsock_is_accept_queue_empty(struct sock *sk) 555 { 556 struct vsock_sock *vsk = vsock_sk(sk); 557 return list_empty(&vsk->accept_queue); 558 } 559 560 static bool vsock_is_pending(struct sock *sk) 561 { 562 struct vsock_sock *vsk = vsock_sk(sk); 563 return !list_empty(&vsk->pending_links); 564 } 565 566 static int vsock_send_shutdown(struct sock *sk, int mode) 567 { 568 struct vsock_sock *vsk = vsock_sk(sk); 569 570 if (!vsk->transport) 571 return -ENODEV; 572 573 return vsk->transport->shutdown(vsk, mode); 574 } 575 576 static void vsock_pending_work(struct work_struct *work) 577 { 578 struct sock *sk; 579 struct sock *listener; 580 struct vsock_sock *vsk; 581 bool cleanup; 582 583 vsk = container_of(work, struct vsock_sock, pending_work.work); 584 sk = sk_vsock(vsk); 585 listener = vsk->listener; 586 cleanup = true; 587 588 lock_sock(listener); 589 lock_sock_nested(sk, SINGLE_DEPTH_NESTING); 590 591 if (vsock_is_pending(sk)) { 592 vsock_remove_pending(listener, sk); 593 594 sk_acceptq_removed(listener); 595 } else if (!vsk->rejected) { 596 /* We are not on the pending list and accept() did not reject 597 * us, so we must have been accepted by our user process. We 598 * just need to drop our references to the sockets and be on 599 * our way. 600 */ 601 cleanup = false; 602 goto out; 603 } 604 605 /* We need to remove ourself from the global connected sockets list so 606 * incoming packets can't find this socket, and to reduce the reference 607 * count. 608 */ 609 vsock_remove_connected(vsk); 610 611 sk->sk_state = TCP_CLOSE; 612 613 out: 614 release_sock(sk); 615 release_sock(listener); 616 if (cleanup) 617 sock_put(sk); 618 619 sock_put(sk); 620 sock_put(listener); 621 } 622 623 /**** SOCKET OPERATIONS ****/ 624 625 static int __vsock_bind_connectible(struct vsock_sock *vsk, 626 struct sockaddr_vm *addr) 627 { 628 static u32 port; 629 struct sockaddr_vm new_addr; 630 631 if (!port) 632 port = get_random_u32_above(LAST_RESERVED_PORT); 633 634 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 635 636 if (addr->svm_port == VMADDR_PORT_ANY) { 637 bool found = false; 638 unsigned int i; 639 640 for (i = 0; i < MAX_PORT_RETRIES; i++) { 641 if (port <= LAST_RESERVED_PORT) 642 port = LAST_RESERVED_PORT + 1; 643 644 new_addr.svm_port = port++; 645 646 if (!__vsock_find_bound_socket(&new_addr)) { 647 found = true; 648 break; 649 } 650 } 651 652 if (!found) 653 return -EADDRNOTAVAIL; 654 } else { 655 /* If port is in reserved range, ensure caller 656 * has necessary privileges. 657 */ 658 if (addr->svm_port <= LAST_RESERVED_PORT && 659 !capable(CAP_NET_BIND_SERVICE)) { 660 return -EACCES; 661 } 662 663 if (__vsock_find_bound_socket(&new_addr)) 664 return -EADDRINUSE; 665 } 666 667 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 668 669 /* Remove connection oriented sockets from the unbound list and add them 670 * to the hash table for easy lookup by its address. The unbound list 671 * is simply an extra entry at the end of the hash table, a trick used 672 * by AF_UNIX. 673 */ 674 __vsock_remove_bound(vsk); 675 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 676 677 return 0; 678 } 679 680 static int __vsock_bind_dgram(struct vsock_sock *vsk, 681 struct sockaddr_vm *addr) 682 { 683 return vsk->transport->dgram_bind(vsk, addr); 684 } 685 686 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 687 { 688 struct vsock_sock *vsk = vsock_sk(sk); 689 int retval; 690 691 /* First ensure this socket isn't already bound. */ 692 if (vsock_addr_bound(&vsk->local_addr)) 693 return -EINVAL; 694 695 /* Now bind to the provided address or select appropriate values if 696 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 697 * like AF_INET prevents binding to a non-local IP address (in most 698 * cases), we only allow binding to a local CID. 699 */ 700 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid)) 701 return -EADDRNOTAVAIL; 702 703 switch (sk->sk_socket->type) { 704 case SOCK_STREAM: 705 case SOCK_SEQPACKET: 706 spin_lock_bh(&vsock_table_lock); 707 retval = __vsock_bind_connectible(vsk, addr); 708 spin_unlock_bh(&vsock_table_lock); 709 break; 710 711 case SOCK_DGRAM: 712 retval = __vsock_bind_dgram(vsk, addr); 713 break; 714 715 default: 716 retval = -EINVAL; 717 break; 718 } 719 720 return retval; 721 } 722 723 static void vsock_connect_timeout(struct work_struct *work); 724 725 static struct sock *__vsock_create(struct net *net, 726 struct socket *sock, 727 struct sock *parent, 728 gfp_t priority, 729 unsigned short type, 730 int kern) 731 { 732 struct sock *sk; 733 struct vsock_sock *psk; 734 struct vsock_sock *vsk; 735 736 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 737 if (!sk) 738 return NULL; 739 740 sock_init_data(sock, sk); 741 742 /* sk->sk_type is normally set in sock_init_data, but only if sock is 743 * non-NULL. We make sure that our sockets always have a type by 744 * setting it here if needed. 745 */ 746 if (!sock) 747 sk->sk_type = type; 748 749 vsk = vsock_sk(sk); 750 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 751 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 752 753 sk->sk_destruct = vsock_sk_destruct; 754 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 755 sock_reset_flag(sk, SOCK_DONE); 756 757 INIT_LIST_HEAD(&vsk->bound_table); 758 INIT_LIST_HEAD(&vsk->connected_table); 759 vsk->listener = NULL; 760 INIT_LIST_HEAD(&vsk->pending_links); 761 INIT_LIST_HEAD(&vsk->accept_queue); 762 vsk->rejected = false; 763 vsk->sent_request = false; 764 vsk->ignore_connecting_rst = false; 765 vsk->peer_shutdown = 0; 766 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 767 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 768 769 psk = parent ? vsock_sk(parent) : NULL; 770 if (parent) { 771 vsk->trusted = psk->trusted; 772 vsk->owner = get_cred(psk->owner); 773 vsk->connect_timeout = psk->connect_timeout; 774 vsk->buffer_size = psk->buffer_size; 775 vsk->buffer_min_size = psk->buffer_min_size; 776 vsk->buffer_max_size = psk->buffer_max_size; 777 security_sk_clone(parent, sk); 778 } else { 779 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN); 780 vsk->owner = get_current_cred(); 781 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 782 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE; 783 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE; 784 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE; 785 } 786 787 return sk; 788 } 789 790 static bool sock_type_connectible(u16 type) 791 { 792 return (type == SOCK_STREAM) || (type == SOCK_SEQPACKET); 793 } 794 795 static void __vsock_release(struct sock *sk, int level) 796 { 797 if (sk) { 798 struct sock *pending; 799 struct vsock_sock *vsk; 800 801 vsk = vsock_sk(sk); 802 pending = NULL; /* Compiler warning. */ 803 804 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 805 * version to avoid the warning "possible recursive locking 806 * detected". When "level" is 0, lock_sock_nested(sk, level) 807 * is the same as lock_sock(sk). 808 */ 809 lock_sock_nested(sk, level); 810 811 if (vsk->transport) 812 vsk->transport->release(vsk); 813 else if (sock_type_connectible(sk->sk_type)) 814 vsock_remove_sock(vsk); 815 816 sock_orphan(sk); 817 sk->sk_shutdown = SHUTDOWN_MASK; 818 819 skb_queue_purge(&sk->sk_receive_queue); 820 821 /* Clean up any sockets that never were accepted. */ 822 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 823 __vsock_release(pending, SINGLE_DEPTH_NESTING); 824 sock_put(pending); 825 } 826 827 release_sock(sk); 828 sock_put(sk); 829 } 830 } 831 832 static void vsock_sk_destruct(struct sock *sk) 833 { 834 struct vsock_sock *vsk = vsock_sk(sk); 835 836 vsock_deassign_transport(vsk); 837 838 /* When clearing these addresses, there's no need to set the family and 839 * possibly register the address family with the kernel. 840 */ 841 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 842 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 843 844 put_cred(vsk->owner); 845 } 846 847 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 848 { 849 int err; 850 851 err = sock_queue_rcv_skb(sk, skb); 852 if (err) 853 kfree_skb(skb); 854 855 return err; 856 } 857 858 struct sock *vsock_create_connected(struct sock *parent) 859 { 860 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL, 861 parent->sk_type, 0); 862 } 863 EXPORT_SYMBOL_GPL(vsock_create_connected); 864 865 s64 vsock_stream_has_data(struct vsock_sock *vsk) 866 { 867 return vsk->transport->stream_has_data(vsk); 868 } 869 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 870 871 s64 vsock_connectible_has_data(struct vsock_sock *vsk) 872 { 873 struct sock *sk = sk_vsock(vsk); 874 875 if (sk->sk_type == SOCK_SEQPACKET) 876 return vsk->transport->seqpacket_has_data(vsk); 877 else 878 return vsock_stream_has_data(vsk); 879 } 880 EXPORT_SYMBOL_GPL(vsock_connectible_has_data); 881 882 s64 vsock_stream_has_space(struct vsock_sock *vsk) 883 { 884 return vsk->transport->stream_has_space(vsk); 885 } 886 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 887 888 void vsock_data_ready(struct sock *sk) 889 { 890 struct vsock_sock *vsk = vsock_sk(sk); 891 892 if (vsock_stream_has_data(vsk) >= sk->sk_rcvlowat || 893 sock_flag(sk, SOCK_DONE)) 894 sk->sk_data_ready(sk); 895 } 896 EXPORT_SYMBOL_GPL(vsock_data_ready); 897 898 static int vsock_release(struct socket *sock) 899 { 900 __vsock_release(sock->sk, 0); 901 sock->sk = NULL; 902 sock->state = SS_FREE; 903 904 return 0; 905 } 906 907 static int 908 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 909 { 910 int err; 911 struct sock *sk; 912 struct sockaddr_vm *vm_addr; 913 914 sk = sock->sk; 915 916 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 917 return -EINVAL; 918 919 lock_sock(sk); 920 err = __vsock_bind(sk, vm_addr); 921 release_sock(sk); 922 923 return err; 924 } 925 926 static int vsock_getname(struct socket *sock, 927 struct sockaddr *addr, int peer) 928 { 929 int err; 930 struct sock *sk; 931 struct vsock_sock *vsk; 932 struct sockaddr_vm *vm_addr; 933 934 sk = sock->sk; 935 vsk = vsock_sk(sk); 936 err = 0; 937 938 lock_sock(sk); 939 940 if (peer) { 941 if (sock->state != SS_CONNECTED) { 942 err = -ENOTCONN; 943 goto out; 944 } 945 vm_addr = &vsk->remote_addr; 946 } else { 947 vm_addr = &vsk->local_addr; 948 } 949 950 if (!vm_addr) { 951 err = -EINVAL; 952 goto out; 953 } 954 955 /* sys_getsockname() and sys_getpeername() pass us a 956 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 957 * that macro is defined in socket.c instead of .h, so we hardcode its 958 * value here. 959 */ 960 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 961 memcpy(addr, vm_addr, sizeof(*vm_addr)); 962 err = sizeof(*vm_addr); 963 964 out: 965 release_sock(sk); 966 return err; 967 } 968 969 static int vsock_shutdown(struct socket *sock, int mode) 970 { 971 int err; 972 struct sock *sk; 973 974 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 975 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 976 * here like the other address families do. Note also that the 977 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 978 * which is what we want. 979 */ 980 mode++; 981 982 if ((mode & ~SHUTDOWN_MASK) || !mode) 983 return -EINVAL; 984 985 /* If this is a connection oriented socket and it is not connected then 986 * bail out immediately. If it is a DGRAM socket then we must first 987 * kick the socket so that it wakes up from any sleeping calls, for 988 * example recv(), and then afterwards return the error. 989 */ 990 991 sk = sock->sk; 992 993 lock_sock(sk); 994 if (sock->state == SS_UNCONNECTED) { 995 err = -ENOTCONN; 996 if (sock_type_connectible(sk->sk_type)) 997 goto out; 998 } else { 999 sock->state = SS_DISCONNECTING; 1000 err = 0; 1001 } 1002 1003 /* Receive and send shutdowns are treated alike. */ 1004 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 1005 if (mode) { 1006 sk->sk_shutdown |= mode; 1007 sk->sk_state_change(sk); 1008 1009 if (sock_type_connectible(sk->sk_type)) { 1010 sock_reset_flag(sk, SOCK_DONE); 1011 vsock_send_shutdown(sk, mode); 1012 } 1013 } 1014 1015 out: 1016 release_sock(sk); 1017 return err; 1018 } 1019 1020 static __poll_t vsock_poll(struct file *file, struct socket *sock, 1021 poll_table *wait) 1022 { 1023 struct sock *sk; 1024 __poll_t mask; 1025 struct vsock_sock *vsk; 1026 1027 sk = sock->sk; 1028 vsk = vsock_sk(sk); 1029 1030 poll_wait(file, sk_sleep(sk), wait); 1031 mask = 0; 1032 1033 if (sk->sk_err) 1034 /* Signify that there has been an error on this socket. */ 1035 mask |= EPOLLERR; 1036 1037 /* INET sockets treat local write shutdown and peer write shutdown as a 1038 * case of EPOLLHUP set. 1039 */ 1040 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 1041 ((sk->sk_shutdown & SEND_SHUTDOWN) && 1042 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 1043 mask |= EPOLLHUP; 1044 } 1045 1046 if (sk->sk_shutdown & RCV_SHUTDOWN || 1047 vsk->peer_shutdown & SEND_SHUTDOWN) { 1048 mask |= EPOLLRDHUP; 1049 } 1050 1051 if (sock->type == SOCK_DGRAM) { 1052 /* For datagram sockets we can read if there is something in 1053 * the queue and write as long as the socket isn't shutdown for 1054 * sending. 1055 */ 1056 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 1057 (sk->sk_shutdown & RCV_SHUTDOWN)) { 1058 mask |= EPOLLIN | EPOLLRDNORM; 1059 } 1060 1061 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1062 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 1063 1064 } else if (sock_type_connectible(sk->sk_type)) { 1065 const struct vsock_transport *transport; 1066 1067 lock_sock(sk); 1068 1069 transport = vsk->transport; 1070 1071 /* Listening sockets that have connections in their accept 1072 * queue can be read. 1073 */ 1074 if (sk->sk_state == TCP_LISTEN 1075 && !vsock_is_accept_queue_empty(sk)) 1076 mask |= EPOLLIN | EPOLLRDNORM; 1077 1078 /* If there is something in the queue then we can read. */ 1079 if (transport && transport->stream_is_active(vsk) && 1080 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1081 bool data_ready_now = false; 1082 int target = sock_rcvlowat(sk, 0, INT_MAX); 1083 int ret = transport->notify_poll_in( 1084 vsk, target, &data_ready_now); 1085 if (ret < 0) { 1086 mask |= EPOLLERR; 1087 } else { 1088 if (data_ready_now) 1089 mask |= EPOLLIN | EPOLLRDNORM; 1090 1091 } 1092 } 1093 1094 /* Sockets whose connections have been closed, reset, or 1095 * terminated should also be considered read, and we check the 1096 * shutdown flag for that. 1097 */ 1098 if (sk->sk_shutdown & RCV_SHUTDOWN || 1099 vsk->peer_shutdown & SEND_SHUTDOWN) { 1100 mask |= EPOLLIN | EPOLLRDNORM; 1101 } 1102 1103 /* Connected sockets that can produce data can be written. */ 1104 if (transport && sk->sk_state == TCP_ESTABLISHED) { 1105 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1106 bool space_avail_now = false; 1107 int ret = transport->notify_poll_out( 1108 vsk, 1, &space_avail_now); 1109 if (ret < 0) { 1110 mask |= EPOLLERR; 1111 } else { 1112 if (space_avail_now) 1113 /* Remove EPOLLWRBAND since INET 1114 * sockets are not setting it. 1115 */ 1116 mask |= EPOLLOUT | EPOLLWRNORM; 1117 1118 } 1119 } 1120 } 1121 1122 /* Simulate INET socket poll behaviors, which sets 1123 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 1124 * but local send is not shutdown. 1125 */ 1126 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 1127 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1128 mask |= EPOLLOUT | EPOLLWRNORM; 1129 1130 } 1131 1132 release_sock(sk); 1133 } 1134 1135 return mask; 1136 } 1137 1138 static int vsock_read_skb(struct sock *sk, skb_read_actor_t read_actor) 1139 { 1140 struct vsock_sock *vsk = vsock_sk(sk); 1141 1142 return vsk->transport->read_skb(vsk, read_actor); 1143 } 1144 1145 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 1146 size_t len) 1147 { 1148 int err; 1149 struct sock *sk; 1150 struct vsock_sock *vsk; 1151 struct sockaddr_vm *remote_addr; 1152 const struct vsock_transport *transport; 1153 1154 if (msg->msg_flags & MSG_OOB) 1155 return -EOPNOTSUPP; 1156 1157 /* For now, MSG_DONTWAIT is always assumed... */ 1158 err = 0; 1159 sk = sock->sk; 1160 vsk = vsock_sk(sk); 1161 1162 lock_sock(sk); 1163 1164 transport = vsk->transport; 1165 1166 err = vsock_auto_bind(vsk); 1167 if (err) 1168 goto out; 1169 1170 1171 /* If the provided message contains an address, use that. Otherwise 1172 * fall back on the socket's remote handle (if it has been connected). 1173 */ 1174 if (msg->msg_name && 1175 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 1176 &remote_addr) == 0) { 1177 /* Ensure this address is of the right type and is a valid 1178 * destination. 1179 */ 1180 1181 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1182 remote_addr->svm_cid = transport->get_local_cid(); 1183 1184 if (!vsock_addr_bound(remote_addr)) { 1185 err = -EINVAL; 1186 goto out; 1187 } 1188 } else if (sock->state == SS_CONNECTED) { 1189 remote_addr = &vsk->remote_addr; 1190 1191 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1192 remote_addr->svm_cid = transport->get_local_cid(); 1193 1194 /* XXX Should connect() or this function ensure remote_addr is 1195 * bound? 1196 */ 1197 if (!vsock_addr_bound(&vsk->remote_addr)) { 1198 err = -EINVAL; 1199 goto out; 1200 } 1201 } else { 1202 err = -EINVAL; 1203 goto out; 1204 } 1205 1206 if (!transport->dgram_allow(remote_addr->svm_cid, 1207 remote_addr->svm_port)) { 1208 err = -EINVAL; 1209 goto out; 1210 } 1211 1212 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1213 1214 out: 1215 release_sock(sk); 1216 return err; 1217 } 1218 1219 static int vsock_dgram_connect(struct socket *sock, 1220 struct sockaddr *addr, int addr_len, int flags) 1221 { 1222 int err; 1223 struct sock *sk; 1224 struct vsock_sock *vsk; 1225 struct sockaddr_vm *remote_addr; 1226 1227 sk = sock->sk; 1228 vsk = vsock_sk(sk); 1229 1230 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1231 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1232 lock_sock(sk); 1233 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1234 VMADDR_PORT_ANY); 1235 sock->state = SS_UNCONNECTED; 1236 release_sock(sk); 1237 return 0; 1238 } else if (err != 0) 1239 return -EINVAL; 1240 1241 lock_sock(sk); 1242 1243 err = vsock_auto_bind(vsk); 1244 if (err) 1245 goto out; 1246 1247 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1248 remote_addr->svm_port)) { 1249 err = -EINVAL; 1250 goto out; 1251 } 1252 1253 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1254 sock->state = SS_CONNECTED; 1255 1256 /* sock map disallows redirection of non-TCP sockets with sk_state != 1257 * TCP_ESTABLISHED (see sock_map_redirect_allowed()), so we set 1258 * TCP_ESTABLISHED here to allow redirection of connected vsock dgrams. 1259 * 1260 * This doesn't seem to be abnormal state for datagram sockets, as the 1261 * same approach can be see in other datagram socket types as well 1262 * (such as unix sockets). 1263 */ 1264 sk->sk_state = TCP_ESTABLISHED; 1265 1266 out: 1267 release_sock(sk); 1268 return err; 1269 } 1270 1271 int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1272 size_t len, int flags) 1273 { 1274 #ifdef CONFIG_BPF_SYSCALL 1275 const struct proto *prot; 1276 #endif 1277 struct vsock_sock *vsk; 1278 struct sock *sk; 1279 1280 sk = sock->sk; 1281 vsk = vsock_sk(sk); 1282 1283 #ifdef CONFIG_BPF_SYSCALL 1284 prot = READ_ONCE(sk->sk_prot); 1285 if (prot != &vsock_proto) 1286 return prot->recvmsg(sk, msg, len, flags, NULL); 1287 #endif 1288 1289 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1290 } 1291 EXPORT_SYMBOL_GPL(vsock_dgram_recvmsg); 1292 1293 static const struct proto_ops vsock_dgram_ops = { 1294 .family = PF_VSOCK, 1295 .owner = THIS_MODULE, 1296 .release = vsock_release, 1297 .bind = vsock_bind, 1298 .connect = vsock_dgram_connect, 1299 .socketpair = sock_no_socketpair, 1300 .accept = sock_no_accept, 1301 .getname = vsock_getname, 1302 .poll = vsock_poll, 1303 .ioctl = sock_no_ioctl, 1304 .listen = sock_no_listen, 1305 .shutdown = vsock_shutdown, 1306 .sendmsg = vsock_dgram_sendmsg, 1307 .recvmsg = vsock_dgram_recvmsg, 1308 .mmap = sock_no_mmap, 1309 .sendpage = sock_no_sendpage, 1310 .read_skb = vsock_read_skb, 1311 }; 1312 1313 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1314 { 1315 const struct vsock_transport *transport = vsk->transport; 1316 1317 if (!transport || !transport->cancel_pkt) 1318 return -EOPNOTSUPP; 1319 1320 return transport->cancel_pkt(vsk); 1321 } 1322 1323 static void vsock_connect_timeout(struct work_struct *work) 1324 { 1325 struct sock *sk; 1326 struct vsock_sock *vsk; 1327 1328 vsk = container_of(work, struct vsock_sock, connect_work.work); 1329 sk = sk_vsock(vsk); 1330 1331 lock_sock(sk); 1332 if (sk->sk_state == TCP_SYN_SENT && 1333 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1334 sk->sk_state = TCP_CLOSE; 1335 sk->sk_socket->state = SS_UNCONNECTED; 1336 sk->sk_err = ETIMEDOUT; 1337 sk_error_report(sk); 1338 vsock_transport_cancel_pkt(vsk); 1339 } 1340 release_sock(sk); 1341 1342 sock_put(sk); 1343 } 1344 1345 static int vsock_connect(struct socket *sock, struct sockaddr *addr, 1346 int addr_len, int flags) 1347 { 1348 int err; 1349 struct sock *sk; 1350 struct vsock_sock *vsk; 1351 const struct vsock_transport *transport; 1352 struct sockaddr_vm *remote_addr; 1353 long timeout; 1354 DEFINE_WAIT(wait); 1355 1356 err = 0; 1357 sk = sock->sk; 1358 vsk = vsock_sk(sk); 1359 1360 lock_sock(sk); 1361 1362 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1363 switch (sock->state) { 1364 case SS_CONNECTED: 1365 err = -EISCONN; 1366 goto out; 1367 case SS_DISCONNECTING: 1368 err = -EINVAL; 1369 goto out; 1370 case SS_CONNECTING: 1371 /* This continues on so we can move sock into the SS_CONNECTED 1372 * state once the connection has completed (at which point err 1373 * will be set to zero also). Otherwise, we will either wait 1374 * for the connection or return -EALREADY should this be a 1375 * non-blocking call. 1376 */ 1377 err = -EALREADY; 1378 if (flags & O_NONBLOCK) 1379 goto out; 1380 break; 1381 default: 1382 if ((sk->sk_state == TCP_LISTEN) || 1383 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1384 err = -EINVAL; 1385 goto out; 1386 } 1387 1388 /* Set the remote address that we are connecting to. */ 1389 memcpy(&vsk->remote_addr, remote_addr, 1390 sizeof(vsk->remote_addr)); 1391 1392 err = vsock_assign_transport(vsk, NULL); 1393 if (err) 1394 goto out; 1395 1396 transport = vsk->transport; 1397 1398 /* The hypervisor and well-known contexts do not have socket 1399 * endpoints. 1400 */ 1401 if (!transport || 1402 !transport->stream_allow(remote_addr->svm_cid, 1403 remote_addr->svm_port)) { 1404 err = -ENETUNREACH; 1405 goto out; 1406 } 1407 1408 err = vsock_auto_bind(vsk); 1409 if (err) 1410 goto out; 1411 1412 sk->sk_state = TCP_SYN_SENT; 1413 1414 err = transport->connect(vsk); 1415 if (err < 0) 1416 goto out; 1417 1418 /* Mark sock as connecting and set the error code to in 1419 * progress in case this is a non-blocking connect. 1420 */ 1421 sock->state = SS_CONNECTING; 1422 err = -EINPROGRESS; 1423 } 1424 1425 /* The receive path will handle all communication until we are able to 1426 * enter the connected state. Here we wait for the connection to be 1427 * completed or a notification of an error. 1428 */ 1429 timeout = vsk->connect_timeout; 1430 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1431 1432 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1433 if (flags & O_NONBLOCK) { 1434 /* If we're not going to block, we schedule a timeout 1435 * function to generate a timeout on the connection 1436 * attempt, in case the peer doesn't respond in a 1437 * timely manner. We hold on to the socket until the 1438 * timeout fires. 1439 */ 1440 sock_hold(sk); 1441 1442 /* If the timeout function is already scheduled, 1443 * reschedule it, then ungrab the socket refcount to 1444 * keep it balanced. 1445 */ 1446 if (mod_delayed_work(system_wq, &vsk->connect_work, 1447 timeout)) 1448 sock_put(sk); 1449 1450 /* Skip ahead to preserve error code set above. */ 1451 goto out_wait; 1452 } 1453 1454 release_sock(sk); 1455 timeout = schedule_timeout(timeout); 1456 lock_sock(sk); 1457 1458 if (signal_pending(current)) { 1459 err = sock_intr_errno(timeout); 1460 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; 1461 sock->state = SS_UNCONNECTED; 1462 vsock_transport_cancel_pkt(vsk); 1463 vsock_remove_connected(vsk); 1464 goto out_wait; 1465 } else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) { 1466 err = -ETIMEDOUT; 1467 sk->sk_state = TCP_CLOSE; 1468 sock->state = SS_UNCONNECTED; 1469 vsock_transport_cancel_pkt(vsk); 1470 goto out_wait; 1471 } 1472 1473 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1474 } 1475 1476 if (sk->sk_err) { 1477 err = -sk->sk_err; 1478 sk->sk_state = TCP_CLOSE; 1479 sock->state = SS_UNCONNECTED; 1480 } else { 1481 err = 0; 1482 } 1483 1484 out_wait: 1485 finish_wait(sk_sleep(sk), &wait); 1486 out: 1487 release_sock(sk); 1488 return err; 1489 } 1490 1491 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1492 bool kern) 1493 { 1494 struct sock *listener; 1495 int err; 1496 struct sock *connected; 1497 struct vsock_sock *vconnected; 1498 long timeout; 1499 DEFINE_WAIT(wait); 1500 1501 err = 0; 1502 listener = sock->sk; 1503 1504 lock_sock(listener); 1505 1506 if (!sock_type_connectible(sock->type)) { 1507 err = -EOPNOTSUPP; 1508 goto out; 1509 } 1510 1511 if (listener->sk_state != TCP_LISTEN) { 1512 err = -EINVAL; 1513 goto out; 1514 } 1515 1516 /* Wait for children sockets to appear; these are the new sockets 1517 * created upon connection establishment. 1518 */ 1519 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1520 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1521 1522 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1523 listener->sk_err == 0) { 1524 release_sock(listener); 1525 timeout = schedule_timeout(timeout); 1526 finish_wait(sk_sleep(listener), &wait); 1527 lock_sock(listener); 1528 1529 if (signal_pending(current)) { 1530 err = sock_intr_errno(timeout); 1531 goto out; 1532 } else if (timeout == 0) { 1533 err = -EAGAIN; 1534 goto out; 1535 } 1536 1537 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1538 } 1539 finish_wait(sk_sleep(listener), &wait); 1540 1541 if (listener->sk_err) 1542 err = -listener->sk_err; 1543 1544 if (connected) { 1545 sk_acceptq_removed(listener); 1546 1547 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1548 vconnected = vsock_sk(connected); 1549 1550 /* If the listener socket has received an error, then we should 1551 * reject this socket and return. Note that we simply mark the 1552 * socket rejected, drop our reference, and let the cleanup 1553 * function handle the cleanup; the fact that we found it in 1554 * the listener's accept queue guarantees that the cleanup 1555 * function hasn't run yet. 1556 */ 1557 if (err) { 1558 vconnected->rejected = true; 1559 } else { 1560 newsock->state = SS_CONNECTED; 1561 sock_graft(connected, newsock); 1562 } 1563 1564 release_sock(connected); 1565 sock_put(connected); 1566 } 1567 1568 out: 1569 release_sock(listener); 1570 return err; 1571 } 1572 1573 static int vsock_listen(struct socket *sock, int backlog) 1574 { 1575 int err; 1576 struct sock *sk; 1577 struct vsock_sock *vsk; 1578 1579 sk = sock->sk; 1580 1581 lock_sock(sk); 1582 1583 if (!sock_type_connectible(sk->sk_type)) { 1584 err = -EOPNOTSUPP; 1585 goto out; 1586 } 1587 1588 if (sock->state != SS_UNCONNECTED) { 1589 err = -EINVAL; 1590 goto out; 1591 } 1592 1593 vsk = vsock_sk(sk); 1594 1595 if (!vsock_addr_bound(&vsk->local_addr)) { 1596 err = -EINVAL; 1597 goto out; 1598 } 1599 1600 sk->sk_max_ack_backlog = backlog; 1601 sk->sk_state = TCP_LISTEN; 1602 1603 err = 0; 1604 1605 out: 1606 release_sock(sk); 1607 return err; 1608 } 1609 1610 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1611 const struct vsock_transport *transport, 1612 u64 val) 1613 { 1614 if (val > vsk->buffer_max_size) 1615 val = vsk->buffer_max_size; 1616 1617 if (val < vsk->buffer_min_size) 1618 val = vsk->buffer_min_size; 1619 1620 if (val != vsk->buffer_size && 1621 transport && transport->notify_buffer_size) 1622 transport->notify_buffer_size(vsk, &val); 1623 1624 vsk->buffer_size = val; 1625 } 1626 1627 static int vsock_connectible_setsockopt(struct socket *sock, 1628 int level, 1629 int optname, 1630 sockptr_t optval, 1631 unsigned int optlen) 1632 { 1633 int err; 1634 struct sock *sk; 1635 struct vsock_sock *vsk; 1636 const struct vsock_transport *transport; 1637 u64 val; 1638 1639 if (level != AF_VSOCK) 1640 return -ENOPROTOOPT; 1641 1642 #define COPY_IN(_v) \ 1643 do { \ 1644 if (optlen < sizeof(_v)) { \ 1645 err = -EINVAL; \ 1646 goto exit; \ 1647 } \ 1648 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1649 err = -EFAULT; \ 1650 goto exit; \ 1651 } \ 1652 } while (0) 1653 1654 err = 0; 1655 sk = sock->sk; 1656 vsk = vsock_sk(sk); 1657 1658 lock_sock(sk); 1659 1660 transport = vsk->transport; 1661 1662 switch (optname) { 1663 case SO_VM_SOCKETS_BUFFER_SIZE: 1664 COPY_IN(val); 1665 vsock_update_buffer_size(vsk, transport, val); 1666 break; 1667 1668 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1669 COPY_IN(val); 1670 vsk->buffer_max_size = val; 1671 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1672 break; 1673 1674 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1675 COPY_IN(val); 1676 vsk->buffer_min_size = val; 1677 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1678 break; 1679 1680 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1681 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: { 1682 struct __kernel_sock_timeval tv; 1683 1684 err = sock_copy_user_timeval(&tv, optval, optlen, 1685 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1686 if (err) 1687 break; 1688 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1689 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1690 vsk->connect_timeout = tv.tv_sec * HZ + 1691 DIV_ROUND_UP((unsigned long)tv.tv_usec, (USEC_PER_SEC / HZ)); 1692 if (vsk->connect_timeout == 0) 1693 vsk->connect_timeout = 1694 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1695 1696 } else { 1697 err = -ERANGE; 1698 } 1699 break; 1700 } 1701 1702 default: 1703 err = -ENOPROTOOPT; 1704 break; 1705 } 1706 1707 #undef COPY_IN 1708 1709 exit: 1710 release_sock(sk); 1711 return err; 1712 } 1713 1714 static int vsock_connectible_getsockopt(struct socket *sock, 1715 int level, int optname, 1716 char __user *optval, 1717 int __user *optlen) 1718 { 1719 struct sock *sk = sock->sk; 1720 struct vsock_sock *vsk = vsock_sk(sk); 1721 1722 union { 1723 u64 val64; 1724 struct old_timeval32 tm32; 1725 struct __kernel_old_timeval tm; 1726 struct __kernel_sock_timeval stm; 1727 } v; 1728 1729 int lv = sizeof(v.val64); 1730 int len; 1731 1732 if (level != AF_VSOCK) 1733 return -ENOPROTOOPT; 1734 1735 if (get_user(len, optlen)) 1736 return -EFAULT; 1737 1738 memset(&v, 0, sizeof(v)); 1739 1740 switch (optname) { 1741 case SO_VM_SOCKETS_BUFFER_SIZE: 1742 v.val64 = vsk->buffer_size; 1743 break; 1744 1745 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1746 v.val64 = vsk->buffer_max_size; 1747 break; 1748 1749 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1750 v.val64 = vsk->buffer_min_size; 1751 break; 1752 1753 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1754 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: 1755 lv = sock_get_timeout(vsk->connect_timeout, &v, 1756 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1757 break; 1758 1759 default: 1760 return -ENOPROTOOPT; 1761 } 1762 1763 if (len < lv) 1764 return -EINVAL; 1765 if (len > lv) 1766 len = lv; 1767 if (copy_to_user(optval, &v, len)) 1768 return -EFAULT; 1769 1770 if (put_user(len, optlen)) 1771 return -EFAULT; 1772 1773 return 0; 1774 } 1775 1776 static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, 1777 size_t len) 1778 { 1779 struct sock *sk; 1780 struct vsock_sock *vsk; 1781 const struct vsock_transport *transport; 1782 ssize_t total_written; 1783 long timeout; 1784 int err; 1785 struct vsock_transport_send_notify_data send_data; 1786 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1787 1788 sk = sock->sk; 1789 vsk = vsock_sk(sk); 1790 total_written = 0; 1791 err = 0; 1792 1793 if (msg->msg_flags & MSG_OOB) 1794 return -EOPNOTSUPP; 1795 1796 lock_sock(sk); 1797 1798 transport = vsk->transport; 1799 1800 /* Callers should not provide a destination with connection oriented 1801 * sockets. 1802 */ 1803 if (msg->msg_namelen) { 1804 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1805 goto out; 1806 } 1807 1808 /* Send data only if both sides are not shutdown in the direction. */ 1809 if (sk->sk_shutdown & SEND_SHUTDOWN || 1810 vsk->peer_shutdown & RCV_SHUTDOWN) { 1811 err = -EPIPE; 1812 goto out; 1813 } 1814 1815 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1816 !vsock_addr_bound(&vsk->local_addr)) { 1817 err = -ENOTCONN; 1818 goto out; 1819 } 1820 1821 if (!vsock_addr_bound(&vsk->remote_addr)) { 1822 err = -EDESTADDRREQ; 1823 goto out; 1824 } 1825 1826 /* Wait for room in the produce queue to enqueue our user's data. */ 1827 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1828 1829 err = transport->notify_send_init(vsk, &send_data); 1830 if (err < 0) 1831 goto out; 1832 1833 while (total_written < len) { 1834 ssize_t written; 1835 1836 add_wait_queue(sk_sleep(sk), &wait); 1837 while (vsock_stream_has_space(vsk) == 0 && 1838 sk->sk_err == 0 && 1839 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1840 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1841 1842 /* Don't wait for non-blocking sockets. */ 1843 if (timeout == 0) { 1844 err = -EAGAIN; 1845 remove_wait_queue(sk_sleep(sk), &wait); 1846 goto out_err; 1847 } 1848 1849 err = transport->notify_send_pre_block(vsk, &send_data); 1850 if (err < 0) { 1851 remove_wait_queue(sk_sleep(sk), &wait); 1852 goto out_err; 1853 } 1854 1855 release_sock(sk); 1856 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1857 lock_sock(sk); 1858 if (signal_pending(current)) { 1859 err = sock_intr_errno(timeout); 1860 remove_wait_queue(sk_sleep(sk), &wait); 1861 goto out_err; 1862 } else if (timeout == 0) { 1863 err = -EAGAIN; 1864 remove_wait_queue(sk_sleep(sk), &wait); 1865 goto out_err; 1866 } 1867 } 1868 remove_wait_queue(sk_sleep(sk), &wait); 1869 1870 /* These checks occur both as part of and after the loop 1871 * conditional since we need to check before and after 1872 * sleeping. 1873 */ 1874 if (sk->sk_err) { 1875 err = -sk->sk_err; 1876 goto out_err; 1877 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1878 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1879 err = -EPIPE; 1880 goto out_err; 1881 } 1882 1883 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1884 if (err < 0) 1885 goto out_err; 1886 1887 /* Note that enqueue will only write as many bytes as are free 1888 * in the produce queue, so we don't need to ensure len is 1889 * smaller than the queue size. It is the caller's 1890 * responsibility to check how many bytes we were able to send. 1891 */ 1892 1893 if (sk->sk_type == SOCK_SEQPACKET) { 1894 written = transport->seqpacket_enqueue(vsk, 1895 msg, len - total_written); 1896 } else { 1897 written = transport->stream_enqueue(vsk, 1898 msg, len - total_written); 1899 } 1900 1901 if (written < 0) { 1902 err = written; 1903 goto out_err; 1904 } 1905 1906 total_written += written; 1907 1908 err = transport->notify_send_post_enqueue( 1909 vsk, written, &send_data); 1910 if (err < 0) 1911 goto out_err; 1912 1913 } 1914 1915 out_err: 1916 if (total_written > 0) { 1917 /* Return number of written bytes only if: 1918 * 1) SOCK_STREAM socket. 1919 * 2) SOCK_SEQPACKET socket when whole buffer is sent. 1920 */ 1921 if (sk->sk_type == SOCK_STREAM || total_written == len) 1922 err = total_written; 1923 } 1924 out: 1925 release_sock(sk); 1926 return err; 1927 } 1928 1929 static int vsock_connectible_wait_data(struct sock *sk, 1930 struct wait_queue_entry *wait, 1931 long timeout, 1932 struct vsock_transport_recv_notify_data *recv_data, 1933 size_t target) 1934 { 1935 const struct vsock_transport *transport; 1936 struct vsock_sock *vsk; 1937 s64 data; 1938 int err; 1939 1940 vsk = vsock_sk(sk); 1941 err = 0; 1942 transport = vsk->transport; 1943 1944 while (1) { 1945 prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); 1946 data = vsock_connectible_has_data(vsk); 1947 if (data != 0) 1948 break; 1949 1950 if (sk->sk_err != 0 || 1951 (sk->sk_shutdown & RCV_SHUTDOWN) || 1952 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1953 break; 1954 } 1955 1956 /* Don't wait for non-blocking sockets. */ 1957 if (timeout == 0) { 1958 err = -EAGAIN; 1959 break; 1960 } 1961 1962 if (recv_data) { 1963 err = transport->notify_recv_pre_block(vsk, target, recv_data); 1964 if (err < 0) 1965 break; 1966 } 1967 1968 release_sock(sk); 1969 timeout = schedule_timeout(timeout); 1970 lock_sock(sk); 1971 1972 if (signal_pending(current)) { 1973 err = sock_intr_errno(timeout); 1974 break; 1975 } else if (timeout == 0) { 1976 err = -EAGAIN; 1977 break; 1978 } 1979 } 1980 1981 finish_wait(sk_sleep(sk), wait); 1982 1983 if (err) 1984 return err; 1985 1986 /* Internal transport error when checking for available 1987 * data. XXX This should be changed to a connection 1988 * reset in a later change. 1989 */ 1990 if (data < 0) 1991 return -ENOMEM; 1992 1993 return data; 1994 } 1995 1996 static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, 1997 size_t len, int flags) 1998 { 1999 struct vsock_transport_recv_notify_data recv_data; 2000 const struct vsock_transport *transport; 2001 struct vsock_sock *vsk; 2002 ssize_t copied; 2003 size_t target; 2004 long timeout; 2005 int err; 2006 2007 DEFINE_WAIT(wait); 2008 2009 vsk = vsock_sk(sk); 2010 transport = vsk->transport; 2011 2012 /* We must not copy less than target bytes into the user's buffer 2013 * before returning successfully, so we wait for the consume queue to 2014 * have that much data to consume before dequeueing. Note that this 2015 * makes it impossible to handle cases where target is greater than the 2016 * queue size. 2017 */ 2018 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 2019 if (target >= transport->stream_rcvhiwat(vsk)) { 2020 err = -ENOMEM; 2021 goto out; 2022 } 2023 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2024 copied = 0; 2025 2026 err = transport->notify_recv_init(vsk, target, &recv_data); 2027 if (err < 0) 2028 goto out; 2029 2030 2031 while (1) { 2032 ssize_t read; 2033 2034 err = vsock_connectible_wait_data(sk, &wait, timeout, 2035 &recv_data, target); 2036 if (err <= 0) 2037 break; 2038 2039 err = transport->notify_recv_pre_dequeue(vsk, target, 2040 &recv_data); 2041 if (err < 0) 2042 break; 2043 2044 read = transport->stream_dequeue(vsk, msg, len - copied, flags); 2045 if (read < 0) { 2046 err = read; 2047 break; 2048 } 2049 2050 copied += read; 2051 2052 err = transport->notify_recv_post_dequeue(vsk, target, read, 2053 !(flags & MSG_PEEK), &recv_data); 2054 if (err < 0) 2055 goto out; 2056 2057 if (read >= target || flags & MSG_PEEK) 2058 break; 2059 2060 target -= read; 2061 } 2062 2063 if (sk->sk_err) 2064 err = -sk->sk_err; 2065 else if (sk->sk_shutdown & RCV_SHUTDOWN) 2066 err = 0; 2067 2068 if (copied > 0) 2069 err = copied; 2070 2071 out: 2072 return err; 2073 } 2074 2075 static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, 2076 size_t len, int flags) 2077 { 2078 const struct vsock_transport *transport; 2079 struct vsock_sock *vsk; 2080 ssize_t msg_len; 2081 long timeout; 2082 int err = 0; 2083 DEFINE_WAIT(wait); 2084 2085 vsk = vsock_sk(sk); 2086 transport = vsk->transport; 2087 2088 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2089 2090 err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0); 2091 if (err <= 0) 2092 goto out; 2093 2094 msg_len = transport->seqpacket_dequeue(vsk, msg, flags); 2095 2096 if (msg_len < 0) { 2097 err = msg_len; 2098 goto out; 2099 } 2100 2101 if (sk->sk_err) { 2102 err = -sk->sk_err; 2103 } else if (sk->sk_shutdown & RCV_SHUTDOWN) { 2104 err = 0; 2105 } else { 2106 /* User sets MSG_TRUNC, so return real length of 2107 * packet. 2108 */ 2109 if (flags & MSG_TRUNC) 2110 err = msg_len; 2111 else 2112 err = len - msg_data_left(msg); 2113 2114 /* Always set MSG_TRUNC if real length of packet is 2115 * bigger than user's buffer. 2116 */ 2117 if (msg_len > len) 2118 msg->msg_flags |= MSG_TRUNC; 2119 } 2120 2121 out: 2122 return err; 2123 } 2124 2125 int 2126 vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2127 int flags) 2128 { 2129 struct sock *sk; 2130 struct vsock_sock *vsk; 2131 const struct vsock_transport *transport; 2132 #ifdef CONFIG_BPF_SYSCALL 2133 const struct proto *prot; 2134 #endif 2135 int err; 2136 2137 sk = sock->sk; 2138 vsk = vsock_sk(sk); 2139 err = 0; 2140 2141 lock_sock(sk); 2142 2143 transport = vsk->transport; 2144 2145 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 2146 /* Recvmsg is supposed to return 0 if a peer performs an 2147 * orderly shutdown. Differentiate between that case and when a 2148 * peer has not connected or a local shutdown occurred with the 2149 * SOCK_DONE flag. 2150 */ 2151 if (sock_flag(sk, SOCK_DONE)) 2152 err = 0; 2153 else 2154 err = -ENOTCONN; 2155 2156 goto out; 2157 } 2158 2159 if (flags & MSG_OOB) { 2160 err = -EOPNOTSUPP; 2161 goto out; 2162 } 2163 2164 /* We don't check peer_shutdown flag here since peer may actually shut 2165 * down, but there can be data in the queue that a local socket can 2166 * receive. 2167 */ 2168 if (sk->sk_shutdown & RCV_SHUTDOWN) { 2169 err = 0; 2170 goto out; 2171 } 2172 2173 /* It is valid on Linux to pass in a zero-length receive buffer. This 2174 * is not an error. We may as well bail out now. 2175 */ 2176 if (!len) { 2177 err = 0; 2178 goto out; 2179 } 2180 2181 #ifdef CONFIG_BPF_SYSCALL 2182 prot = READ_ONCE(sk->sk_prot); 2183 if (prot != &vsock_proto) { 2184 release_sock(sk); 2185 return prot->recvmsg(sk, msg, len, flags, NULL); 2186 } 2187 #endif 2188 2189 if (sk->sk_type == SOCK_STREAM) 2190 err = __vsock_stream_recvmsg(sk, msg, len, flags); 2191 else 2192 err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); 2193 2194 out: 2195 release_sock(sk); 2196 return err; 2197 } 2198 EXPORT_SYMBOL_GPL(vsock_connectible_recvmsg); 2199 2200 static int vsock_set_rcvlowat(struct sock *sk, int val) 2201 { 2202 const struct vsock_transport *transport; 2203 struct vsock_sock *vsk; 2204 2205 vsk = vsock_sk(sk); 2206 2207 if (val > vsk->buffer_size) 2208 return -EINVAL; 2209 2210 transport = vsk->transport; 2211 2212 if (transport && transport->set_rcvlowat) 2213 return transport->set_rcvlowat(vsk, val); 2214 2215 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 2216 return 0; 2217 } 2218 2219 static const struct proto_ops vsock_stream_ops = { 2220 .family = PF_VSOCK, 2221 .owner = THIS_MODULE, 2222 .release = vsock_release, 2223 .bind = vsock_bind, 2224 .connect = vsock_connect, 2225 .socketpair = sock_no_socketpair, 2226 .accept = vsock_accept, 2227 .getname = vsock_getname, 2228 .poll = vsock_poll, 2229 .ioctl = sock_no_ioctl, 2230 .listen = vsock_listen, 2231 .shutdown = vsock_shutdown, 2232 .setsockopt = vsock_connectible_setsockopt, 2233 .getsockopt = vsock_connectible_getsockopt, 2234 .sendmsg = vsock_connectible_sendmsg, 2235 .recvmsg = vsock_connectible_recvmsg, 2236 .mmap = sock_no_mmap, 2237 .sendpage = sock_no_sendpage, 2238 .set_rcvlowat = vsock_set_rcvlowat, 2239 .read_skb = vsock_read_skb, 2240 }; 2241 2242 static const struct proto_ops vsock_seqpacket_ops = { 2243 .family = PF_VSOCK, 2244 .owner = THIS_MODULE, 2245 .release = vsock_release, 2246 .bind = vsock_bind, 2247 .connect = vsock_connect, 2248 .socketpair = sock_no_socketpair, 2249 .accept = vsock_accept, 2250 .getname = vsock_getname, 2251 .poll = vsock_poll, 2252 .ioctl = sock_no_ioctl, 2253 .listen = vsock_listen, 2254 .shutdown = vsock_shutdown, 2255 .setsockopt = vsock_connectible_setsockopt, 2256 .getsockopt = vsock_connectible_getsockopt, 2257 .sendmsg = vsock_connectible_sendmsg, 2258 .recvmsg = vsock_connectible_recvmsg, 2259 .mmap = sock_no_mmap, 2260 .sendpage = sock_no_sendpage, 2261 .read_skb = vsock_read_skb, 2262 }; 2263 2264 static int vsock_create(struct net *net, struct socket *sock, 2265 int protocol, int kern) 2266 { 2267 struct vsock_sock *vsk; 2268 struct sock *sk; 2269 int ret; 2270 2271 if (!sock) 2272 return -EINVAL; 2273 2274 if (protocol && protocol != PF_VSOCK) 2275 return -EPROTONOSUPPORT; 2276 2277 switch (sock->type) { 2278 case SOCK_DGRAM: 2279 sock->ops = &vsock_dgram_ops; 2280 break; 2281 case SOCK_STREAM: 2282 sock->ops = &vsock_stream_ops; 2283 break; 2284 case SOCK_SEQPACKET: 2285 sock->ops = &vsock_seqpacket_ops; 2286 break; 2287 default: 2288 return -ESOCKTNOSUPPORT; 2289 } 2290 2291 sock->state = SS_UNCONNECTED; 2292 2293 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2294 if (!sk) 2295 return -ENOMEM; 2296 2297 vsk = vsock_sk(sk); 2298 2299 if (sock->type == SOCK_DGRAM) { 2300 ret = vsock_assign_transport(vsk, NULL); 2301 if (ret < 0) { 2302 sock_put(sk); 2303 return ret; 2304 } 2305 } 2306 2307 vsock_insert_unbound(vsk); 2308 2309 return 0; 2310 } 2311 2312 static const struct net_proto_family vsock_family_ops = { 2313 .family = AF_VSOCK, 2314 .create = vsock_create, 2315 .owner = THIS_MODULE, 2316 }; 2317 2318 static long vsock_dev_do_ioctl(struct file *filp, 2319 unsigned int cmd, void __user *ptr) 2320 { 2321 u32 __user *p = ptr; 2322 u32 cid = VMADDR_CID_ANY; 2323 int retval = 0; 2324 2325 switch (cmd) { 2326 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2327 /* To be compatible with the VMCI behavior, we prioritize the 2328 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2329 */ 2330 if (transport_g2h) 2331 cid = transport_g2h->get_local_cid(); 2332 else if (transport_h2g) 2333 cid = transport_h2g->get_local_cid(); 2334 2335 if (put_user(cid, p) != 0) 2336 retval = -EFAULT; 2337 break; 2338 2339 default: 2340 retval = -ENOIOCTLCMD; 2341 } 2342 2343 return retval; 2344 } 2345 2346 static long vsock_dev_ioctl(struct file *filp, 2347 unsigned int cmd, unsigned long arg) 2348 { 2349 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2350 } 2351 2352 #ifdef CONFIG_COMPAT 2353 static long vsock_dev_compat_ioctl(struct file *filp, 2354 unsigned int cmd, unsigned long arg) 2355 { 2356 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2357 } 2358 #endif 2359 2360 static const struct file_operations vsock_device_ops = { 2361 .owner = THIS_MODULE, 2362 .unlocked_ioctl = vsock_dev_ioctl, 2363 #ifdef CONFIG_COMPAT 2364 .compat_ioctl = vsock_dev_compat_ioctl, 2365 #endif 2366 .open = nonseekable_open, 2367 }; 2368 2369 static struct miscdevice vsock_device = { 2370 .name = "vsock", 2371 .fops = &vsock_device_ops, 2372 }; 2373 2374 static int __init vsock_init(void) 2375 { 2376 int err = 0; 2377 2378 vsock_init_tables(); 2379 2380 vsock_proto.owner = THIS_MODULE; 2381 vsock_device.minor = MISC_DYNAMIC_MINOR; 2382 err = misc_register(&vsock_device); 2383 if (err) { 2384 pr_err("Failed to register misc device\n"); 2385 goto err_reset_transport; 2386 } 2387 2388 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2389 if (err) { 2390 pr_err("Cannot register vsock protocol\n"); 2391 goto err_deregister_misc; 2392 } 2393 2394 err = sock_register(&vsock_family_ops); 2395 if (err) { 2396 pr_err("could not register af_vsock (%d) address family: %d\n", 2397 AF_VSOCK, err); 2398 goto err_unregister_proto; 2399 } 2400 2401 vsock_bpf_build_proto(); 2402 2403 return 0; 2404 2405 err_unregister_proto: 2406 proto_unregister(&vsock_proto); 2407 err_deregister_misc: 2408 misc_deregister(&vsock_device); 2409 err_reset_transport: 2410 return err; 2411 } 2412 2413 static void __exit vsock_exit(void) 2414 { 2415 misc_deregister(&vsock_device); 2416 sock_unregister(AF_VSOCK); 2417 proto_unregister(&vsock_proto); 2418 } 2419 2420 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2421 { 2422 return vsk->transport; 2423 } 2424 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2425 2426 int vsock_core_register(const struct vsock_transport *t, int features) 2427 { 2428 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2429 int err = mutex_lock_interruptible(&vsock_register_mutex); 2430 2431 if (err) 2432 return err; 2433 2434 t_h2g = transport_h2g; 2435 t_g2h = transport_g2h; 2436 t_dgram = transport_dgram; 2437 t_local = transport_local; 2438 2439 if (features & VSOCK_TRANSPORT_F_H2G) { 2440 if (t_h2g) { 2441 err = -EBUSY; 2442 goto err_busy; 2443 } 2444 t_h2g = t; 2445 } 2446 2447 if (features & VSOCK_TRANSPORT_F_G2H) { 2448 if (t_g2h) { 2449 err = -EBUSY; 2450 goto err_busy; 2451 } 2452 t_g2h = t; 2453 } 2454 2455 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2456 if (t_dgram) { 2457 err = -EBUSY; 2458 goto err_busy; 2459 } 2460 t_dgram = t; 2461 } 2462 2463 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2464 if (t_local) { 2465 err = -EBUSY; 2466 goto err_busy; 2467 } 2468 t_local = t; 2469 } 2470 2471 transport_h2g = t_h2g; 2472 transport_g2h = t_g2h; 2473 transport_dgram = t_dgram; 2474 transport_local = t_local; 2475 2476 err_busy: 2477 mutex_unlock(&vsock_register_mutex); 2478 return err; 2479 } 2480 EXPORT_SYMBOL_GPL(vsock_core_register); 2481 2482 void vsock_core_unregister(const struct vsock_transport *t) 2483 { 2484 mutex_lock(&vsock_register_mutex); 2485 2486 if (transport_h2g == t) 2487 transport_h2g = NULL; 2488 2489 if (transport_g2h == t) 2490 transport_g2h = NULL; 2491 2492 if (transport_dgram == t) 2493 transport_dgram = NULL; 2494 2495 if (transport_local == t) 2496 transport_local = NULL; 2497 2498 mutex_unlock(&vsock_register_mutex); 2499 } 2500 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2501 2502 module_init(vsock_init); 2503 module_exit(vsock_exit); 2504 2505 MODULE_AUTHOR("VMware, Inc."); 2506 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2507 MODULE_VERSION("1.0.2.0-k"); 2508 MODULE_LICENSE("GPL v2"); 2509