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 .read_skb = vsock_read_skb, 1310 }; 1311 1312 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1313 { 1314 const struct vsock_transport *transport = vsk->transport; 1315 1316 if (!transport || !transport->cancel_pkt) 1317 return -EOPNOTSUPP; 1318 1319 return transport->cancel_pkt(vsk); 1320 } 1321 1322 static void vsock_connect_timeout(struct work_struct *work) 1323 { 1324 struct sock *sk; 1325 struct vsock_sock *vsk; 1326 1327 vsk = container_of(work, struct vsock_sock, connect_work.work); 1328 sk = sk_vsock(vsk); 1329 1330 lock_sock(sk); 1331 if (sk->sk_state == TCP_SYN_SENT && 1332 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1333 sk->sk_state = TCP_CLOSE; 1334 sk->sk_socket->state = SS_UNCONNECTED; 1335 sk->sk_err = ETIMEDOUT; 1336 sk_error_report(sk); 1337 vsock_transport_cancel_pkt(vsk); 1338 } 1339 release_sock(sk); 1340 1341 sock_put(sk); 1342 } 1343 1344 static int vsock_connect(struct socket *sock, struct sockaddr *addr, 1345 int addr_len, int flags) 1346 { 1347 int err; 1348 struct sock *sk; 1349 struct vsock_sock *vsk; 1350 const struct vsock_transport *transport; 1351 struct sockaddr_vm *remote_addr; 1352 long timeout; 1353 DEFINE_WAIT(wait); 1354 1355 err = 0; 1356 sk = sock->sk; 1357 vsk = vsock_sk(sk); 1358 1359 lock_sock(sk); 1360 1361 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1362 switch (sock->state) { 1363 case SS_CONNECTED: 1364 err = -EISCONN; 1365 goto out; 1366 case SS_DISCONNECTING: 1367 err = -EINVAL; 1368 goto out; 1369 case SS_CONNECTING: 1370 /* This continues on so we can move sock into the SS_CONNECTED 1371 * state once the connection has completed (at which point err 1372 * will be set to zero also). Otherwise, we will either wait 1373 * for the connection or return -EALREADY should this be a 1374 * non-blocking call. 1375 */ 1376 err = -EALREADY; 1377 if (flags & O_NONBLOCK) 1378 goto out; 1379 break; 1380 default: 1381 if ((sk->sk_state == TCP_LISTEN) || 1382 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1383 err = -EINVAL; 1384 goto out; 1385 } 1386 1387 /* Set the remote address that we are connecting to. */ 1388 memcpy(&vsk->remote_addr, remote_addr, 1389 sizeof(vsk->remote_addr)); 1390 1391 err = vsock_assign_transport(vsk, NULL); 1392 if (err) 1393 goto out; 1394 1395 transport = vsk->transport; 1396 1397 /* The hypervisor and well-known contexts do not have socket 1398 * endpoints. 1399 */ 1400 if (!transport || 1401 !transport->stream_allow(remote_addr->svm_cid, 1402 remote_addr->svm_port)) { 1403 err = -ENETUNREACH; 1404 goto out; 1405 } 1406 1407 err = vsock_auto_bind(vsk); 1408 if (err) 1409 goto out; 1410 1411 sk->sk_state = TCP_SYN_SENT; 1412 1413 err = transport->connect(vsk); 1414 if (err < 0) 1415 goto out; 1416 1417 /* Mark sock as connecting and set the error code to in 1418 * progress in case this is a non-blocking connect. 1419 */ 1420 sock->state = SS_CONNECTING; 1421 err = -EINPROGRESS; 1422 } 1423 1424 /* The receive path will handle all communication until we are able to 1425 * enter the connected state. Here we wait for the connection to be 1426 * completed or a notification of an error. 1427 */ 1428 timeout = vsk->connect_timeout; 1429 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1430 1431 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1432 if (flags & O_NONBLOCK) { 1433 /* If we're not going to block, we schedule a timeout 1434 * function to generate a timeout on the connection 1435 * attempt, in case the peer doesn't respond in a 1436 * timely manner. We hold on to the socket until the 1437 * timeout fires. 1438 */ 1439 sock_hold(sk); 1440 1441 /* If the timeout function is already scheduled, 1442 * reschedule it, then ungrab the socket refcount to 1443 * keep it balanced. 1444 */ 1445 if (mod_delayed_work(system_wq, &vsk->connect_work, 1446 timeout)) 1447 sock_put(sk); 1448 1449 /* Skip ahead to preserve error code set above. */ 1450 goto out_wait; 1451 } 1452 1453 release_sock(sk); 1454 timeout = schedule_timeout(timeout); 1455 lock_sock(sk); 1456 1457 if (signal_pending(current)) { 1458 err = sock_intr_errno(timeout); 1459 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; 1460 sock->state = SS_UNCONNECTED; 1461 vsock_transport_cancel_pkt(vsk); 1462 vsock_remove_connected(vsk); 1463 goto out_wait; 1464 } else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) { 1465 err = -ETIMEDOUT; 1466 sk->sk_state = TCP_CLOSE; 1467 sock->state = SS_UNCONNECTED; 1468 vsock_transport_cancel_pkt(vsk); 1469 goto out_wait; 1470 } 1471 1472 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1473 } 1474 1475 if (sk->sk_err) { 1476 err = -sk->sk_err; 1477 sk->sk_state = TCP_CLOSE; 1478 sock->state = SS_UNCONNECTED; 1479 } else { 1480 err = 0; 1481 } 1482 1483 out_wait: 1484 finish_wait(sk_sleep(sk), &wait); 1485 out: 1486 release_sock(sk); 1487 return err; 1488 } 1489 1490 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1491 bool kern) 1492 { 1493 struct sock *listener; 1494 int err; 1495 struct sock *connected; 1496 struct vsock_sock *vconnected; 1497 long timeout; 1498 DEFINE_WAIT(wait); 1499 1500 err = 0; 1501 listener = sock->sk; 1502 1503 lock_sock(listener); 1504 1505 if (!sock_type_connectible(sock->type)) { 1506 err = -EOPNOTSUPP; 1507 goto out; 1508 } 1509 1510 if (listener->sk_state != TCP_LISTEN) { 1511 err = -EINVAL; 1512 goto out; 1513 } 1514 1515 /* Wait for children sockets to appear; these are the new sockets 1516 * created upon connection establishment. 1517 */ 1518 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1519 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1520 1521 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1522 listener->sk_err == 0) { 1523 release_sock(listener); 1524 timeout = schedule_timeout(timeout); 1525 finish_wait(sk_sleep(listener), &wait); 1526 lock_sock(listener); 1527 1528 if (signal_pending(current)) { 1529 err = sock_intr_errno(timeout); 1530 goto out; 1531 } else if (timeout == 0) { 1532 err = -EAGAIN; 1533 goto out; 1534 } 1535 1536 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1537 } 1538 finish_wait(sk_sleep(listener), &wait); 1539 1540 if (listener->sk_err) 1541 err = -listener->sk_err; 1542 1543 if (connected) { 1544 sk_acceptq_removed(listener); 1545 1546 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1547 vconnected = vsock_sk(connected); 1548 1549 /* If the listener socket has received an error, then we should 1550 * reject this socket and return. Note that we simply mark the 1551 * socket rejected, drop our reference, and let the cleanup 1552 * function handle the cleanup; the fact that we found it in 1553 * the listener's accept queue guarantees that the cleanup 1554 * function hasn't run yet. 1555 */ 1556 if (err) { 1557 vconnected->rejected = true; 1558 } else { 1559 newsock->state = SS_CONNECTED; 1560 sock_graft(connected, newsock); 1561 } 1562 1563 release_sock(connected); 1564 sock_put(connected); 1565 } 1566 1567 out: 1568 release_sock(listener); 1569 return err; 1570 } 1571 1572 static int vsock_listen(struct socket *sock, int backlog) 1573 { 1574 int err; 1575 struct sock *sk; 1576 struct vsock_sock *vsk; 1577 1578 sk = sock->sk; 1579 1580 lock_sock(sk); 1581 1582 if (!sock_type_connectible(sk->sk_type)) { 1583 err = -EOPNOTSUPP; 1584 goto out; 1585 } 1586 1587 if (sock->state != SS_UNCONNECTED) { 1588 err = -EINVAL; 1589 goto out; 1590 } 1591 1592 vsk = vsock_sk(sk); 1593 1594 if (!vsock_addr_bound(&vsk->local_addr)) { 1595 err = -EINVAL; 1596 goto out; 1597 } 1598 1599 sk->sk_max_ack_backlog = backlog; 1600 sk->sk_state = TCP_LISTEN; 1601 1602 err = 0; 1603 1604 out: 1605 release_sock(sk); 1606 return err; 1607 } 1608 1609 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1610 const struct vsock_transport *transport, 1611 u64 val) 1612 { 1613 if (val > vsk->buffer_max_size) 1614 val = vsk->buffer_max_size; 1615 1616 if (val < vsk->buffer_min_size) 1617 val = vsk->buffer_min_size; 1618 1619 if (val != vsk->buffer_size && 1620 transport && transport->notify_buffer_size) 1621 transport->notify_buffer_size(vsk, &val); 1622 1623 vsk->buffer_size = val; 1624 } 1625 1626 static int vsock_connectible_setsockopt(struct socket *sock, 1627 int level, 1628 int optname, 1629 sockptr_t optval, 1630 unsigned int optlen) 1631 { 1632 int err; 1633 struct sock *sk; 1634 struct vsock_sock *vsk; 1635 const struct vsock_transport *transport; 1636 u64 val; 1637 1638 if (level != AF_VSOCK) 1639 return -ENOPROTOOPT; 1640 1641 #define COPY_IN(_v) \ 1642 do { \ 1643 if (optlen < sizeof(_v)) { \ 1644 err = -EINVAL; \ 1645 goto exit; \ 1646 } \ 1647 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1648 err = -EFAULT; \ 1649 goto exit; \ 1650 } \ 1651 } while (0) 1652 1653 err = 0; 1654 sk = sock->sk; 1655 vsk = vsock_sk(sk); 1656 1657 lock_sock(sk); 1658 1659 transport = vsk->transport; 1660 1661 switch (optname) { 1662 case SO_VM_SOCKETS_BUFFER_SIZE: 1663 COPY_IN(val); 1664 vsock_update_buffer_size(vsk, transport, val); 1665 break; 1666 1667 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1668 COPY_IN(val); 1669 vsk->buffer_max_size = val; 1670 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1671 break; 1672 1673 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1674 COPY_IN(val); 1675 vsk->buffer_min_size = val; 1676 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1677 break; 1678 1679 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1680 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: { 1681 struct __kernel_sock_timeval tv; 1682 1683 err = sock_copy_user_timeval(&tv, optval, optlen, 1684 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1685 if (err) 1686 break; 1687 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1688 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1689 vsk->connect_timeout = tv.tv_sec * HZ + 1690 DIV_ROUND_UP((unsigned long)tv.tv_usec, (USEC_PER_SEC / HZ)); 1691 if (vsk->connect_timeout == 0) 1692 vsk->connect_timeout = 1693 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1694 1695 } else { 1696 err = -ERANGE; 1697 } 1698 break; 1699 } 1700 1701 default: 1702 err = -ENOPROTOOPT; 1703 break; 1704 } 1705 1706 #undef COPY_IN 1707 1708 exit: 1709 release_sock(sk); 1710 return err; 1711 } 1712 1713 static int vsock_connectible_getsockopt(struct socket *sock, 1714 int level, int optname, 1715 char __user *optval, 1716 int __user *optlen) 1717 { 1718 struct sock *sk = sock->sk; 1719 struct vsock_sock *vsk = vsock_sk(sk); 1720 1721 union { 1722 u64 val64; 1723 struct old_timeval32 tm32; 1724 struct __kernel_old_timeval tm; 1725 struct __kernel_sock_timeval stm; 1726 } v; 1727 1728 int lv = sizeof(v.val64); 1729 int len; 1730 1731 if (level != AF_VSOCK) 1732 return -ENOPROTOOPT; 1733 1734 if (get_user(len, optlen)) 1735 return -EFAULT; 1736 1737 memset(&v, 0, sizeof(v)); 1738 1739 switch (optname) { 1740 case SO_VM_SOCKETS_BUFFER_SIZE: 1741 v.val64 = vsk->buffer_size; 1742 break; 1743 1744 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1745 v.val64 = vsk->buffer_max_size; 1746 break; 1747 1748 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1749 v.val64 = vsk->buffer_min_size; 1750 break; 1751 1752 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1753 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: 1754 lv = sock_get_timeout(vsk->connect_timeout, &v, 1755 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1756 break; 1757 1758 default: 1759 return -ENOPROTOOPT; 1760 } 1761 1762 if (len < lv) 1763 return -EINVAL; 1764 if (len > lv) 1765 len = lv; 1766 if (copy_to_user(optval, &v, len)) 1767 return -EFAULT; 1768 1769 if (put_user(len, optlen)) 1770 return -EFAULT; 1771 1772 return 0; 1773 } 1774 1775 static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, 1776 size_t len) 1777 { 1778 struct sock *sk; 1779 struct vsock_sock *vsk; 1780 const struct vsock_transport *transport; 1781 ssize_t total_written; 1782 long timeout; 1783 int err; 1784 struct vsock_transport_send_notify_data send_data; 1785 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1786 1787 sk = sock->sk; 1788 vsk = vsock_sk(sk); 1789 total_written = 0; 1790 err = 0; 1791 1792 if (msg->msg_flags & MSG_OOB) 1793 return -EOPNOTSUPP; 1794 1795 lock_sock(sk); 1796 1797 transport = vsk->transport; 1798 1799 /* Callers should not provide a destination with connection oriented 1800 * sockets. 1801 */ 1802 if (msg->msg_namelen) { 1803 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1804 goto out; 1805 } 1806 1807 /* Send data only if both sides are not shutdown in the direction. */ 1808 if (sk->sk_shutdown & SEND_SHUTDOWN || 1809 vsk->peer_shutdown & RCV_SHUTDOWN) { 1810 err = -EPIPE; 1811 goto out; 1812 } 1813 1814 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1815 !vsock_addr_bound(&vsk->local_addr)) { 1816 err = -ENOTCONN; 1817 goto out; 1818 } 1819 1820 if (!vsock_addr_bound(&vsk->remote_addr)) { 1821 err = -EDESTADDRREQ; 1822 goto out; 1823 } 1824 1825 /* Wait for room in the produce queue to enqueue our user's data. */ 1826 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1827 1828 err = transport->notify_send_init(vsk, &send_data); 1829 if (err < 0) 1830 goto out; 1831 1832 while (total_written < len) { 1833 ssize_t written; 1834 1835 add_wait_queue(sk_sleep(sk), &wait); 1836 while (vsock_stream_has_space(vsk) == 0 && 1837 sk->sk_err == 0 && 1838 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1839 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1840 1841 /* Don't wait for non-blocking sockets. */ 1842 if (timeout == 0) { 1843 err = -EAGAIN; 1844 remove_wait_queue(sk_sleep(sk), &wait); 1845 goto out_err; 1846 } 1847 1848 err = transport->notify_send_pre_block(vsk, &send_data); 1849 if (err < 0) { 1850 remove_wait_queue(sk_sleep(sk), &wait); 1851 goto out_err; 1852 } 1853 1854 release_sock(sk); 1855 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1856 lock_sock(sk); 1857 if (signal_pending(current)) { 1858 err = sock_intr_errno(timeout); 1859 remove_wait_queue(sk_sleep(sk), &wait); 1860 goto out_err; 1861 } else if (timeout == 0) { 1862 err = -EAGAIN; 1863 remove_wait_queue(sk_sleep(sk), &wait); 1864 goto out_err; 1865 } 1866 } 1867 remove_wait_queue(sk_sleep(sk), &wait); 1868 1869 /* These checks occur both as part of and after the loop 1870 * conditional since we need to check before and after 1871 * sleeping. 1872 */ 1873 if (sk->sk_err) { 1874 err = -sk->sk_err; 1875 goto out_err; 1876 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1877 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1878 err = -EPIPE; 1879 goto out_err; 1880 } 1881 1882 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1883 if (err < 0) 1884 goto out_err; 1885 1886 /* Note that enqueue will only write as many bytes as are free 1887 * in the produce queue, so we don't need to ensure len is 1888 * smaller than the queue size. It is the caller's 1889 * responsibility to check how many bytes we were able to send. 1890 */ 1891 1892 if (sk->sk_type == SOCK_SEQPACKET) { 1893 written = transport->seqpacket_enqueue(vsk, 1894 msg, len - total_written); 1895 } else { 1896 written = transport->stream_enqueue(vsk, 1897 msg, len - total_written); 1898 } 1899 1900 if (written < 0) { 1901 err = written; 1902 goto out_err; 1903 } 1904 1905 total_written += written; 1906 1907 err = transport->notify_send_post_enqueue( 1908 vsk, written, &send_data); 1909 if (err < 0) 1910 goto out_err; 1911 1912 } 1913 1914 out_err: 1915 if (total_written > 0) { 1916 /* Return number of written bytes only if: 1917 * 1) SOCK_STREAM socket. 1918 * 2) SOCK_SEQPACKET socket when whole buffer is sent. 1919 */ 1920 if (sk->sk_type == SOCK_STREAM || total_written == len) 1921 err = total_written; 1922 } 1923 out: 1924 release_sock(sk); 1925 return err; 1926 } 1927 1928 static int vsock_connectible_wait_data(struct sock *sk, 1929 struct wait_queue_entry *wait, 1930 long timeout, 1931 struct vsock_transport_recv_notify_data *recv_data, 1932 size_t target) 1933 { 1934 const struct vsock_transport *transport; 1935 struct vsock_sock *vsk; 1936 s64 data; 1937 int err; 1938 1939 vsk = vsock_sk(sk); 1940 err = 0; 1941 transport = vsk->transport; 1942 1943 while (1) { 1944 prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); 1945 data = vsock_connectible_has_data(vsk); 1946 if (data != 0) 1947 break; 1948 1949 if (sk->sk_err != 0 || 1950 (sk->sk_shutdown & RCV_SHUTDOWN) || 1951 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1952 break; 1953 } 1954 1955 /* Don't wait for non-blocking sockets. */ 1956 if (timeout == 0) { 1957 err = -EAGAIN; 1958 break; 1959 } 1960 1961 if (recv_data) { 1962 err = transport->notify_recv_pre_block(vsk, target, recv_data); 1963 if (err < 0) 1964 break; 1965 } 1966 1967 release_sock(sk); 1968 timeout = schedule_timeout(timeout); 1969 lock_sock(sk); 1970 1971 if (signal_pending(current)) { 1972 err = sock_intr_errno(timeout); 1973 break; 1974 } else if (timeout == 0) { 1975 err = -EAGAIN; 1976 break; 1977 } 1978 } 1979 1980 finish_wait(sk_sleep(sk), wait); 1981 1982 if (err) 1983 return err; 1984 1985 /* Internal transport error when checking for available 1986 * data. XXX This should be changed to a connection 1987 * reset in a later change. 1988 */ 1989 if (data < 0) 1990 return -ENOMEM; 1991 1992 return data; 1993 } 1994 1995 static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, 1996 size_t len, int flags) 1997 { 1998 struct vsock_transport_recv_notify_data recv_data; 1999 const struct vsock_transport *transport; 2000 struct vsock_sock *vsk; 2001 ssize_t copied; 2002 size_t target; 2003 long timeout; 2004 int err; 2005 2006 DEFINE_WAIT(wait); 2007 2008 vsk = vsock_sk(sk); 2009 transport = vsk->transport; 2010 2011 /* We must not copy less than target bytes into the user's buffer 2012 * before returning successfully, so we wait for the consume queue to 2013 * have that much data to consume before dequeueing. Note that this 2014 * makes it impossible to handle cases where target is greater than the 2015 * queue size. 2016 */ 2017 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 2018 if (target >= transport->stream_rcvhiwat(vsk)) { 2019 err = -ENOMEM; 2020 goto out; 2021 } 2022 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2023 copied = 0; 2024 2025 err = transport->notify_recv_init(vsk, target, &recv_data); 2026 if (err < 0) 2027 goto out; 2028 2029 2030 while (1) { 2031 ssize_t read; 2032 2033 err = vsock_connectible_wait_data(sk, &wait, timeout, 2034 &recv_data, target); 2035 if (err <= 0) 2036 break; 2037 2038 err = transport->notify_recv_pre_dequeue(vsk, target, 2039 &recv_data); 2040 if (err < 0) 2041 break; 2042 2043 read = transport->stream_dequeue(vsk, msg, len - copied, flags); 2044 if (read < 0) { 2045 err = read; 2046 break; 2047 } 2048 2049 copied += read; 2050 2051 err = transport->notify_recv_post_dequeue(vsk, target, read, 2052 !(flags & MSG_PEEK), &recv_data); 2053 if (err < 0) 2054 goto out; 2055 2056 if (read >= target || flags & MSG_PEEK) 2057 break; 2058 2059 target -= read; 2060 } 2061 2062 if (sk->sk_err) 2063 err = -sk->sk_err; 2064 else if (sk->sk_shutdown & RCV_SHUTDOWN) 2065 err = 0; 2066 2067 if (copied > 0) 2068 err = copied; 2069 2070 out: 2071 return err; 2072 } 2073 2074 static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, 2075 size_t len, int flags) 2076 { 2077 const struct vsock_transport *transport; 2078 struct vsock_sock *vsk; 2079 ssize_t msg_len; 2080 long timeout; 2081 int err = 0; 2082 DEFINE_WAIT(wait); 2083 2084 vsk = vsock_sk(sk); 2085 transport = vsk->transport; 2086 2087 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2088 2089 err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0); 2090 if (err <= 0) 2091 goto out; 2092 2093 msg_len = transport->seqpacket_dequeue(vsk, msg, flags); 2094 2095 if (msg_len < 0) { 2096 err = msg_len; 2097 goto out; 2098 } 2099 2100 if (sk->sk_err) { 2101 err = -sk->sk_err; 2102 } else if (sk->sk_shutdown & RCV_SHUTDOWN) { 2103 err = 0; 2104 } else { 2105 /* User sets MSG_TRUNC, so return real length of 2106 * packet. 2107 */ 2108 if (flags & MSG_TRUNC) 2109 err = msg_len; 2110 else 2111 err = len - msg_data_left(msg); 2112 2113 /* Always set MSG_TRUNC if real length of packet is 2114 * bigger than user's buffer. 2115 */ 2116 if (msg_len > len) 2117 msg->msg_flags |= MSG_TRUNC; 2118 } 2119 2120 out: 2121 return err; 2122 } 2123 2124 int 2125 vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2126 int flags) 2127 { 2128 struct sock *sk; 2129 struct vsock_sock *vsk; 2130 const struct vsock_transport *transport; 2131 #ifdef CONFIG_BPF_SYSCALL 2132 const struct proto *prot; 2133 #endif 2134 int err; 2135 2136 sk = sock->sk; 2137 vsk = vsock_sk(sk); 2138 err = 0; 2139 2140 lock_sock(sk); 2141 2142 transport = vsk->transport; 2143 2144 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 2145 /* Recvmsg is supposed to return 0 if a peer performs an 2146 * orderly shutdown. Differentiate between that case and when a 2147 * peer has not connected or a local shutdown occurred with the 2148 * SOCK_DONE flag. 2149 */ 2150 if (sock_flag(sk, SOCK_DONE)) 2151 err = 0; 2152 else 2153 err = -ENOTCONN; 2154 2155 goto out; 2156 } 2157 2158 if (flags & MSG_OOB) { 2159 err = -EOPNOTSUPP; 2160 goto out; 2161 } 2162 2163 /* We don't check peer_shutdown flag here since peer may actually shut 2164 * down, but there can be data in the queue that a local socket can 2165 * receive. 2166 */ 2167 if (sk->sk_shutdown & RCV_SHUTDOWN) { 2168 err = 0; 2169 goto out; 2170 } 2171 2172 /* It is valid on Linux to pass in a zero-length receive buffer. This 2173 * is not an error. We may as well bail out now. 2174 */ 2175 if (!len) { 2176 err = 0; 2177 goto out; 2178 } 2179 2180 #ifdef CONFIG_BPF_SYSCALL 2181 prot = READ_ONCE(sk->sk_prot); 2182 if (prot != &vsock_proto) { 2183 release_sock(sk); 2184 return prot->recvmsg(sk, msg, len, flags, NULL); 2185 } 2186 #endif 2187 2188 if (sk->sk_type == SOCK_STREAM) 2189 err = __vsock_stream_recvmsg(sk, msg, len, flags); 2190 else 2191 err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); 2192 2193 out: 2194 release_sock(sk); 2195 return err; 2196 } 2197 EXPORT_SYMBOL_GPL(vsock_connectible_recvmsg); 2198 2199 static int vsock_set_rcvlowat(struct sock *sk, int val) 2200 { 2201 const struct vsock_transport *transport; 2202 struct vsock_sock *vsk; 2203 2204 vsk = vsock_sk(sk); 2205 2206 if (val > vsk->buffer_size) 2207 return -EINVAL; 2208 2209 transport = vsk->transport; 2210 2211 if (transport && transport->set_rcvlowat) 2212 return transport->set_rcvlowat(vsk, val); 2213 2214 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 2215 return 0; 2216 } 2217 2218 static const struct proto_ops vsock_stream_ops = { 2219 .family = PF_VSOCK, 2220 .owner = THIS_MODULE, 2221 .release = vsock_release, 2222 .bind = vsock_bind, 2223 .connect = vsock_connect, 2224 .socketpair = sock_no_socketpair, 2225 .accept = vsock_accept, 2226 .getname = vsock_getname, 2227 .poll = vsock_poll, 2228 .ioctl = sock_no_ioctl, 2229 .listen = vsock_listen, 2230 .shutdown = vsock_shutdown, 2231 .setsockopt = vsock_connectible_setsockopt, 2232 .getsockopt = vsock_connectible_getsockopt, 2233 .sendmsg = vsock_connectible_sendmsg, 2234 .recvmsg = vsock_connectible_recvmsg, 2235 .mmap = sock_no_mmap, 2236 .set_rcvlowat = vsock_set_rcvlowat, 2237 .read_skb = vsock_read_skb, 2238 }; 2239 2240 static const struct proto_ops vsock_seqpacket_ops = { 2241 .family = PF_VSOCK, 2242 .owner = THIS_MODULE, 2243 .release = vsock_release, 2244 .bind = vsock_bind, 2245 .connect = vsock_connect, 2246 .socketpair = sock_no_socketpair, 2247 .accept = vsock_accept, 2248 .getname = vsock_getname, 2249 .poll = vsock_poll, 2250 .ioctl = sock_no_ioctl, 2251 .listen = vsock_listen, 2252 .shutdown = vsock_shutdown, 2253 .setsockopt = vsock_connectible_setsockopt, 2254 .getsockopt = vsock_connectible_getsockopt, 2255 .sendmsg = vsock_connectible_sendmsg, 2256 .recvmsg = vsock_connectible_recvmsg, 2257 .mmap = sock_no_mmap, 2258 .read_skb = vsock_read_skb, 2259 }; 2260 2261 static int vsock_create(struct net *net, struct socket *sock, 2262 int protocol, int kern) 2263 { 2264 struct vsock_sock *vsk; 2265 struct sock *sk; 2266 int ret; 2267 2268 if (!sock) 2269 return -EINVAL; 2270 2271 if (protocol && protocol != PF_VSOCK) 2272 return -EPROTONOSUPPORT; 2273 2274 switch (sock->type) { 2275 case SOCK_DGRAM: 2276 sock->ops = &vsock_dgram_ops; 2277 break; 2278 case SOCK_STREAM: 2279 sock->ops = &vsock_stream_ops; 2280 break; 2281 case SOCK_SEQPACKET: 2282 sock->ops = &vsock_seqpacket_ops; 2283 break; 2284 default: 2285 return -ESOCKTNOSUPPORT; 2286 } 2287 2288 sock->state = SS_UNCONNECTED; 2289 2290 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2291 if (!sk) 2292 return -ENOMEM; 2293 2294 vsk = vsock_sk(sk); 2295 2296 if (sock->type == SOCK_DGRAM) { 2297 ret = vsock_assign_transport(vsk, NULL); 2298 if (ret < 0) { 2299 sock_put(sk); 2300 return ret; 2301 } 2302 } 2303 2304 vsock_insert_unbound(vsk); 2305 2306 return 0; 2307 } 2308 2309 static const struct net_proto_family vsock_family_ops = { 2310 .family = AF_VSOCK, 2311 .create = vsock_create, 2312 .owner = THIS_MODULE, 2313 }; 2314 2315 static long vsock_dev_do_ioctl(struct file *filp, 2316 unsigned int cmd, void __user *ptr) 2317 { 2318 u32 __user *p = ptr; 2319 u32 cid = VMADDR_CID_ANY; 2320 int retval = 0; 2321 2322 switch (cmd) { 2323 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2324 /* To be compatible with the VMCI behavior, we prioritize the 2325 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2326 */ 2327 if (transport_g2h) 2328 cid = transport_g2h->get_local_cid(); 2329 else if (transport_h2g) 2330 cid = transport_h2g->get_local_cid(); 2331 2332 if (put_user(cid, p) != 0) 2333 retval = -EFAULT; 2334 break; 2335 2336 default: 2337 retval = -ENOIOCTLCMD; 2338 } 2339 2340 return retval; 2341 } 2342 2343 static long vsock_dev_ioctl(struct file *filp, 2344 unsigned int cmd, unsigned long arg) 2345 { 2346 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2347 } 2348 2349 #ifdef CONFIG_COMPAT 2350 static long vsock_dev_compat_ioctl(struct file *filp, 2351 unsigned int cmd, unsigned long arg) 2352 { 2353 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2354 } 2355 #endif 2356 2357 static const struct file_operations vsock_device_ops = { 2358 .owner = THIS_MODULE, 2359 .unlocked_ioctl = vsock_dev_ioctl, 2360 #ifdef CONFIG_COMPAT 2361 .compat_ioctl = vsock_dev_compat_ioctl, 2362 #endif 2363 .open = nonseekable_open, 2364 }; 2365 2366 static struct miscdevice vsock_device = { 2367 .name = "vsock", 2368 .fops = &vsock_device_ops, 2369 }; 2370 2371 static int __init vsock_init(void) 2372 { 2373 int err = 0; 2374 2375 vsock_init_tables(); 2376 2377 vsock_proto.owner = THIS_MODULE; 2378 vsock_device.minor = MISC_DYNAMIC_MINOR; 2379 err = misc_register(&vsock_device); 2380 if (err) { 2381 pr_err("Failed to register misc device\n"); 2382 goto err_reset_transport; 2383 } 2384 2385 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2386 if (err) { 2387 pr_err("Cannot register vsock protocol\n"); 2388 goto err_deregister_misc; 2389 } 2390 2391 err = sock_register(&vsock_family_ops); 2392 if (err) { 2393 pr_err("could not register af_vsock (%d) address family: %d\n", 2394 AF_VSOCK, err); 2395 goto err_unregister_proto; 2396 } 2397 2398 vsock_bpf_build_proto(); 2399 2400 return 0; 2401 2402 err_unregister_proto: 2403 proto_unregister(&vsock_proto); 2404 err_deregister_misc: 2405 misc_deregister(&vsock_device); 2406 err_reset_transport: 2407 return err; 2408 } 2409 2410 static void __exit vsock_exit(void) 2411 { 2412 misc_deregister(&vsock_device); 2413 sock_unregister(AF_VSOCK); 2414 proto_unregister(&vsock_proto); 2415 } 2416 2417 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2418 { 2419 return vsk->transport; 2420 } 2421 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2422 2423 int vsock_core_register(const struct vsock_transport *t, int features) 2424 { 2425 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2426 int err = mutex_lock_interruptible(&vsock_register_mutex); 2427 2428 if (err) 2429 return err; 2430 2431 t_h2g = transport_h2g; 2432 t_g2h = transport_g2h; 2433 t_dgram = transport_dgram; 2434 t_local = transport_local; 2435 2436 if (features & VSOCK_TRANSPORT_F_H2G) { 2437 if (t_h2g) { 2438 err = -EBUSY; 2439 goto err_busy; 2440 } 2441 t_h2g = t; 2442 } 2443 2444 if (features & VSOCK_TRANSPORT_F_G2H) { 2445 if (t_g2h) { 2446 err = -EBUSY; 2447 goto err_busy; 2448 } 2449 t_g2h = t; 2450 } 2451 2452 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2453 if (t_dgram) { 2454 err = -EBUSY; 2455 goto err_busy; 2456 } 2457 t_dgram = t; 2458 } 2459 2460 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2461 if (t_local) { 2462 err = -EBUSY; 2463 goto err_busy; 2464 } 2465 t_local = t; 2466 } 2467 2468 transport_h2g = t_h2g; 2469 transport_g2h = t_g2h; 2470 transport_dgram = t_dgram; 2471 transport_local = t_local; 2472 2473 err_busy: 2474 mutex_unlock(&vsock_register_mutex); 2475 return err; 2476 } 2477 EXPORT_SYMBOL_GPL(vsock_core_register); 2478 2479 void vsock_core_unregister(const struct vsock_transport *t) 2480 { 2481 mutex_lock(&vsock_register_mutex); 2482 2483 if (transport_h2g == t) 2484 transport_h2g = NULL; 2485 2486 if (transport_g2h == t) 2487 transport_g2h = NULL; 2488 2489 if (transport_dgram == t) 2490 transport_dgram = NULL; 2491 2492 if (transport_local == t) 2493 transport_local = NULL; 2494 2495 mutex_unlock(&vsock_register_mutex); 2496 } 2497 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2498 2499 module_init(vsock_init); 2500 module_exit(vsock_exit); 2501 2502 MODULE_AUTHOR("VMware, Inc."); 2503 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2504 MODULE_VERSION("1.0.2.0-k"); 2505 MODULE_LICENSE("GPL v2"); 2506