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/errqueue.h> 93 #include <linux/init.h> 94 #include <linux/io.h> 95 #include <linux/kernel.h> 96 #include <linux/sched/signal.h> 97 #include <linux/kmod.h> 98 #include <linux/list.h> 99 #include <linux/miscdevice.h> 100 #include <linux/module.h> 101 #include <linux/mutex.h> 102 #include <linux/net.h> 103 #include <linux/poll.h> 104 #include <linux/random.h> 105 #include <linux/skbuff.h> 106 #include <linux/smp.h> 107 #include <linux/socket.h> 108 #include <linux/stddef.h> 109 #include <linux/unistd.h> 110 #include <linux/wait.h> 111 #include <linux/workqueue.h> 112 #include <net/sock.h> 113 #include <net/af_vsock.h> 114 #include <uapi/linux/vm_sockets.h> 115 116 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr); 117 static void vsock_sk_destruct(struct sock *sk); 118 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 119 120 /* Protocol family. */ 121 struct proto vsock_proto = { 122 .name = "AF_VSOCK", 123 .owner = THIS_MODULE, 124 .obj_size = sizeof(struct vsock_sock), 125 #ifdef CONFIG_BPF_SYSCALL 126 .psock_update_sk_prot = vsock_bpf_update_proto, 127 #endif 128 }; 129 130 /* The default peer timeout indicates how long we will wait for a peer response 131 * to a control message. 132 */ 133 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ) 134 135 #define VSOCK_DEFAULT_BUFFER_SIZE (1024 * 256) 136 #define VSOCK_DEFAULT_BUFFER_MAX_SIZE (1024 * 256) 137 #define VSOCK_DEFAULT_BUFFER_MIN_SIZE 128 138 139 /* Transport used for host->guest communication */ 140 static const struct vsock_transport *transport_h2g; 141 /* Transport used for guest->host communication */ 142 static const struct vsock_transport *transport_g2h; 143 /* Transport used for DGRAM communication */ 144 static const struct vsock_transport *transport_dgram; 145 /* Transport used for local communication */ 146 static const struct vsock_transport *transport_local; 147 static DEFINE_MUTEX(vsock_register_mutex); 148 149 /**** UTILS ****/ 150 151 /* Each bound VSocket is stored in the bind hash table and each connected 152 * VSocket is stored in the connected hash table. 153 * 154 * Unbound sockets are all put on the same list attached to the end of the hash 155 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in 156 * the bucket that their local address hashes to (vsock_bound_sockets(addr) 157 * represents the list that addr hashes to). 158 * 159 * Specifically, we initialize the vsock_bind_table array to a size of 160 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through 161 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and 162 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function 163 * mods with VSOCK_HASH_SIZE to ensure this. 164 */ 165 #define MAX_PORT_RETRIES 24 166 167 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE) 168 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)]) 169 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE]) 170 171 /* XXX This can probably be implemented in a better way. */ 172 #define VSOCK_CONN_HASH(src, dst) \ 173 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE) 174 #define vsock_connected_sockets(src, dst) \ 175 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)]) 176 #define vsock_connected_sockets_vsk(vsk) \ 177 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr) 178 179 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 180 EXPORT_SYMBOL_GPL(vsock_bind_table); 181 struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 182 EXPORT_SYMBOL_GPL(vsock_connected_table); 183 DEFINE_SPINLOCK(vsock_table_lock); 184 EXPORT_SYMBOL_GPL(vsock_table_lock); 185 186 /* Autobind this socket to the local address if necessary. */ 187 static int vsock_auto_bind(struct vsock_sock *vsk) 188 { 189 struct sock *sk = sk_vsock(vsk); 190 struct sockaddr_vm local_addr; 191 192 if (vsock_addr_bound(&vsk->local_addr)) 193 return 0; 194 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 195 return __vsock_bind(sk, &local_addr); 196 } 197 198 static void vsock_init_tables(void) 199 { 200 int i; 201 202 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++) 203 INIT_LIST_HEAD(&vsock_bind_table[i]); 204 205 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) 206 INIT_LIST_HEAD(&vsock_connected_table[i]); 207 } 208 209 static void __vsock_insert_bound(struct list_head *list, 210 struct vsock_sock *vsk) 211 { 212 sock_hold(&vsk->sk); 213 list_add(&vsk->bound_table, list); 214 } 215 216 static void __vsock_insert_connected(struct list_head *list, 217 struct vsock_sock *vsk) 218 { 219 sock_hold(&vsk->sk); 220 list_add(&vsk->connected_table, list); 221 } 222 223 static void __vsock_remove_bound(struct vsock_sock *vsk) 224 { 225 list_del_init(&vsk->bound_table); 226 sock_put(&vsk->sk); 227 } 228 229 static void __vsock_remove_connected(struct vsock_sock *vsk) 230 { 231 list_del_init(&vsk->connected_table); 232 sock_put(&vsk->sk); 233 } 234 235 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr) 236 { 237 struct vsock_sock *vsk; 238 239 list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) { 240 if (vsock_addr_equals_addr(addr, &vsk->local_addr)) 241 return sk_vsock(vsk); 242 243 if (addr->svm_port == vsk->local_addr.svm_port && 244 (vsk->local_addr.svm_cid == VMADDR_CID_ANY || 245 addr->svm_cid == VMADDR_CID_ANY)) 246 return sk_vsock(vsk); 247 } 248 249 return NULL; 250 } 251 252 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src, 253 struct sockaddr_vm *dst) 254 { 255 struct vsock_sock *vsk; 256 257 list_for_each_entry(vsk, vsock_connected_sockets(src, dst), 258 connected_table) { 259 if (vsock_addr_equals_addr(src, &vsk->remote_addr) && 260 dst->svm_port == vsk->local_addr.svm_port) { 261 return sk_vsock(vsk); 262 } 263 } 264 265 return NULL; 266 } 267 268 static void vsock_insert_unbound(struct vsock_sock *vsk) 269 { 270 spin_lock_bh(&vsock_table_lock); 271 __vsock_insert_bound(vsock_unbound_sockets, vsk); 272 spin_unlock_bh(&vsock_table_lock); 273 } 274 275 void vsock_insert_connected(struct vsock_sock *vsk) 276 { 277 struct list_head *list = vsock_connected_sockets( 278 &vsk->remote_addr, &vsk->local_addr); 279 280 spin_lock_bh(&vsock_table_lock); 281 __vsock_insert_connected(list, vsk); 282 spin_unlock_bh(&vsock_table_lock); 283 } 284 EXPORT_SYMBOL_GPL(vsock_insert_connected); 285 286 void vsock_remove_bound(struct vsock_sock *vsk) 287 { 288 spin_lock_bh(&vsock_table_lock); 289 if (__vsock_in_bound_table(vsk)) 290 __vsock_remove_bound(vsk); 291 spin_unlock_bh(&vsock_table_lock); 292 } 293 EXPORT_SYMBOL_GPL(vsock_remove_bound); 294 295 void vsock_remove_connected(struct vsock_sock *vsk) 296 { 297 spin_lock_bh(&vsock_table_lock); 298 if (__vsock_in_connected_table(vsk)) 299 __vsock_remove_connected(vsk); 300 spin_unlock_bh(&vsock_table_lock); 301 } 302 EXPORT_SYMBOL_GPL(vsock_remove_connected); 303 304 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr) 305 { 306 struct sock *sk; 307 308 spin_lock_bh(&vsock_table_lock); 309 sk = __vsock_find_bound_socket(addr); 310 if (sk) 311 sock_hold(sk); 312 313 spin_unlock_bh(&vsock_table_lock); 314 315 return sk; 316 } 317 EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 318 319 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, 320 struct sockaddr_vm *dst) 321 { 322 struct sock *sk; 323 324 spin_lock_bh(&vsock_table_lock); 325 sk = __vsock_find_connected_socket(src, dst); 326 if (sk) 327 sock_hold(sk); 328 329 spin_unlock_bh(&vsock_table_lock); 330 331 return sk; 332 } 333 EXPORT_SYMBOL_GPL(vsock_find_connected_socket); 334 335 void vsock_remove_sock(struct vsock_sock *vsk) 336 { 337 vsock_remove_bound(vsk); 338 vsock_remove_connected(vsk); 339 } 340 EXPORT_SYMBOL_GPL(vsock_remove_sock); 341 342 void vsock_for_each_connected_socket(struct vsock_transport *transport, 343 void (*fn)(struct sock *sk)) 344 { 345 int i; 346 347 spin_lock_bh(&vsock_table_lock); 348 349 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) { 350 struct vsock_sock *vsk; 351 list_for_each_entry(vsk, &vsock_connected_table[i], 352 connected_table) { 353 if (vsk->transport != transport) 354 continue; 355 356 fn(sk_vsock(vsk)); 357 } 358 } 359 360 spin_unlock_bh(&vsock_table_lock); 361 } 362 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket); 363 364 void vsock_add_pending(struct sock *listener, struct sock *pending) 365 { 366 struct vsock_sock *vlistener; 367 struct vsock_sock *vpending; 368 369 vlistener = vsock_sk(listener); 370 vpending = vsock_sk(pending); 371 372 sock_hold(pending); 373 sock_hold(listener); 374 list_add_tail(&vpending->pending_links, &vlistener->pending_links); 375 } 376 EXPORT_SYMBOL_GPL(vsock_add_pending); 377 378 void vsock_remove_pending(struct sock *listener, struct sock *pending) 379 { 380 struct vsock_sock *vpending = vsock_sk(pending); 381 382 list_del_init(&vpending->pending_links); 383 sock_put(listener); 384 sock_put(pending); 385 } 386 EXPORT_SYMBOL_GPL(vsock_remove_pending); 387 388 void vsock_enqueue_accept(struct sock *listener, struct sock *connected) 389 { 390 struct vsock_sock *vlistener; 391 struct vsock_sock *vconnected; 392 393 vlistener = vsock_sk(listener); 394 vconnected = vsock_sk(connected); 395 396 sock_hold(connected); 397 sock_hold(listener); 398 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue); 399 } 400 EXPORT_SYMBOL_GPL(vsock_enqueue_accept); 401 402 static bool vsock_use_local_transport(unsigned int remote_cid) 403 { 404 if (!transport_local) 405 return false; 406 407 if (remote_cid == VMADDR_CID_LOCAL) 408 return true; 409 410 if (transport_g2h) { 411 return remote_cid == transport_g2h->get_local_cid(); 412 } else { 413 return remote_cid == VMADDR_CID_HOST; 414 } 415 } 416 417 static void vsock_deassign_transport(struct vsock_sock *vsk) 418 { 419 if (!vsk->transport) 420 return; 421 422 vsk->transport->destruct(vsk); 423 module_put(vsk->transport->module); 424 vsk->transport = NULL; 425 } 426 427 /* Assign a transport to a socket and call the .init transport callback. 428 * 429 * Note: for connection oriented socket this must be called when vsk->remote_addr 430 * is set (e.g. during the connect() or when a connection request on a listener 431 * socket is received). 432 * The vsk->remote_addr is used to decide which transport to use: 433 * - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if 434 * g2h is not loaded, will use local transport; 435 * - remote CID <= VMADDR_CID_HOST or h2g is not loaded or remote flags field 436 * includes VMADDR_FLAG_TO_HOST flag value, will use guest->host transport; 437 * - remote CID > VMADDR_CID_HOST will use host->guest transport; 438 */ 439 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk) 440 { 441 const struct vsock_transport *new_transport; 442 struct sock *sk = sk_vsock(vsk); 443 unsigned int remote_cid = vsk->remote_addr.svm_cid; 444 __u8 remote_flags; 445 int ret; 446 447 /* If the packet is coming with the source and destination CIDs higher 448 * than VMADDR_CID_HOST, then a vsock channel where all the packets are 449 * forwarded to the host should be established. Then the host will 450 * need to forward the packets to the guest. 451 * 452 * The flag is set on the (listen) receive path (psk is not NULL). On 453 * the connect path the flag can be set by the user space application. 454 */ 455 if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST && 456 vsk->remote_addr.svm_cid > VMADDR_CID_HOST) 457 vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST; 458 459 remote_flags = vsk->remote_addr.svm_flags; 460 461 switch (sk->sk_type) { 462 case SOCK_DGRAM: 463 new_transport = transport_dgram; 464 break; 465 case SOCK_STREAM: 466 case SOCK_SEQPACKET: 467 if (vsock_use_local_transport(remote_cid)) 468 new_transport = transport_local; 469 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g || 470 (remote_flags & VMADDR_FLAG_TO_HOST)) 471 new_transport = transport_g2h; 472 else 473 new_transport = transport_h2g; 474 break; 475 default: 476 return -ESOCKTNOSUPPORT; 477 } 478 479 if (vsk->transport) { 480 if (vsk->transport == new_transport) 481 return 0; 482 483 /* transport->release() must be called with sock lock acquired. 484 * This path can only be taken during vsock_connect(), where we 485 * have already held the sock lock. In the other cases, this 486 * function is called on a new socket which is not assigned to 487 * any transport. 488 */ 489 vsk->transport->release(vsk); 490 vsock_deassign_transport(vsk); 491 } 492 493 /* We increase the module refcnt to prevent the transport unloading 494 * while there are open sockets assigned to it. 495 */ 496 if (!new_transport || !try_module_get(new_transport->module)) 497 return -ENODEV; 498 499 if (sk->sk_type == SOCK_SEQPACKET) { 500 if (!new_transport->seqpacket_allow || 501 !new_transport->seqpacket_allow(remote_cid)) { 502 module_put(new_transport->module); 503 return -ESOCKTNOSUPPORT; 504 } 505 } 506 507 ret = new_transport->init(vsk, psk); 508 if (ret) { 509 module_put(new_transport->module); 510 return ret; 511 } 512 513 vsk->transport = new_transport; 514 515 return 0; 516 } 517 EXPORT_SYMBOL_GPL(vsock_assign_transport); 518 519 bool vsock_find_cid(unsigned int cid) 520 { 521 if (transport_g2h && cid == transport_g2h->get_local_cid()) 522 return true; 523 524 if (transport_h2g && cid == VMADDR_CID_HOST) 525 return true; 526 527 if (transport_local && cid == VMADDR_CID_LOCAL) 528 return true; 529 530 return false; 531 } 532 EXPORT_SYMBOL_GPL(vsock_find_cid); 533 534 static struct sock *vsock_dequeue_accept(struct sock *listener) 535 { 536 struct vsock_sock *vlistener; 537 struct vsock_sock *vconnected; 538 539 vlistener = vsock_sk(listener); 540 541 if (list_empty(&vlistener->accept_queue)) 542 return NULL; 543 544 vconnected = list_entry(vlistener->accept_queue.next, 545 struct vsock_sock, accept_queue); 546 547 list_del_init(&vconnected->accept_queue); 548 sock_put(listener); 549 /* The caller will need a reference on the connected socket so we let 550 * it call sock_put(). 551 */ 552 553 return sk_vsock(vconnected); 554 } 555 556 static bool vsock_is_accept_queue_empty(struct sock *sk) 557 { 558 struct vsock_sock *vsk = vsock_sk(sk); 559 return list_empty(&vsk->accept_queue); 560 } 561 562 static bool vsock_is_pending(struct sock *sk) 563 { 564 struct vsock_sock *vsk = vsock_sk(sk); 565 return !list_empty(&vsk->pending_links); 566 } 567 568 static int vsock_send_shutdown(struct sock *sk, int mode) 569 { 570 struct vsock_sock *vsk = vsock_sk(sk); 571 572 if (!vsk->transport) 573 return -ENODEV; 574 575 return vsk->transport->shutdown(vsk, mode); 576 } 577 578 static void vsock_pending_work(struct work_struct *work) 579 { 580 struct sock *sk; 581 struct sock *listener; 582 struct vsock_sock *vsk; 583 bool cleanup; 584 585 vsk = container_of(work, struct vsock_sock, pending_work.work); 586 sk = sk_vsock(vsk); 587 listener = vsk->listener; 588 cleanup = true; 589 590 lock_sock(listener); 591 lock_sock_nested(sk, SINGLE_DEPTH_NESTING); 592 593 if (vsock_is_pending(sk)) { 594 vsock_remove_pending(listener, sk); 595 596 sk_acceptq_removed(listener); 597 } else if (!vsk->rejected) { 598 /* We are not on the pending list and accept() did not reject 599 * us, so we must have been accepted by our user process. We 600 * just need to drop our references to the sockets and be on 601 * our way. 602 */ 603 cleanup = false; 604 goto out; 605 } 606 607 /* We need to remove ourself from the global connected sockets list so 608 * incoming packets can't find this socket, and to reduce the reference 609 * count. 610 */ 611 vsock_remove_connected(vsk); 612 613 sk->sk_state = TCP_CLOSE; 614 615 out: 616 release_sock(sk); 617 release_sock(listener); 618 if (cleanup) 619 sock_put(sk); 620 621 sock_put(sk); 622 sock_put(listener); 623 } 624 625 /**** SOCKET OPERATIONS ****/ 626 627 static int __vsock_bind_connectible(struct vsock_sock *vsk, 628 struct sockaddr_vm *addr) 629 { 630 static u32 port; 631 struct sockaddr_vm new_addr; 632 633 if (!port) 634 port = get_random_u32_above(LAST_RESERVED_PORT); 635 636 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 637 638 if (addr->svm_port == VMADDR_PORT_ANY) { 639 bool found = false; 640 unsigned int i; 641 642 for (i = 0; i < MAX_PORT_RETRIES; i++) { 643 if (port <= LAST_RESERVED_PORT) 644 port = LAST_RESERVED_PORT + 1; 645 646 new_addr.svm_port = port++; 647 648 if (!__vsock_find_bound_socket(&new_addr)) { 649 found = true; 650 break; 651 } 652 } 653 654 if (!found) 655 return -EADDRNOTAVAIL; 656 } else { 657 /* If port is in reserved range, ensure caller 658 * has necessary privileges. 659 */ 660 if (addr->svm_port <= LAST_RESERVED_PORT && 661 !capable(CAP_NET_BIND_SERVICE)) { 662 return -EACCES; 663 } 664 665 if (__vsock_find_bound_socket(&new_addr)) 666 return -EADDRINUSE; 667 } 668 669 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 670 671 /* Remove connection oriented sockets from the unbound list and add them 672 * to the hash table for easy lookup by its address. The unbound list 673 * is simply an extra entry at the end of the hash table, a trick used 674 * by AF_UNIX. 675 */ 676 __vsock_remove_bound(vsk); 677 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 678 679 return 0; 680 } 681 682 static int __vsock_bind_dgram(struct vsock_sock *vsk, 683 struct sockaddr_vm *addr) 684 { 685 return vsk->transport->dgram_bind(vsk, addr); 686 } 687 688 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 689 { 690 struct vsock_sock *vsk = vsock_sk(sk); 691 int retval; 692 693 /* First ensure this socket isn't already bound. */ 694 if (vsock_addr_bound(&vsk->local_addr)) 695 return -EINVAL; 696 697 /* Now bind to the provided address or select appropriate values if 698 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 699 * like AF_INET prevents binding to a non-local IP address (in most 700 * cases), we only allow binding to a local CID. 701 */ 702 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid)) 703 return -EADDRNOTAVAIL; 704 705 switch (sk->sk_socket->type) { 706 case SOCK_STREAM: 707 case SOCK_SEQPACKET: 708 spin_lock_bh(&vsock_table_lock); 709 retval = __vsock_bind_connectible(vsk, addr); 710 spin_unlock_bh(&vsock_table_lock); 711 break; 712 713 case SOCK_DGRAM: 714 retval = __vsock_bind_dgram(vsk, addr); 715 break; 716 717 default: 718 retval = -EINVAL; 719 break; 720 } 721 722 return retval; 723 } 724 725 static void vsock_connect_timeout(struct work_struct *work); 726 727 static struct sock *__vsock_create(struct net *net, 728 struct socket *sock, 729 struct sock *parent, 730 gfp_t priority, 731 unsigned short type, 732 int kern) 733 { 734 struct sock *sk; 735 struct vsock_sock *psk; 736 struct vsock_sock *vsk; 737 738 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 739 if (!sk) 740 return NULL; 741 742 sock_init_data(sock, sk); 743 744 /* sk->sk_type is normally set in sock_init_data, but only if sock is 745 * non-NULL. We make sure that our sockets always have a type by 746 * setting it here if needed. 747 */ 748 if (!sock) 749 sk->sk_type = type; 750 751 vsk = vsock_sk(sk); 752 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 753 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 754 755 sk->sk_destruct = vsock_sk_destruct; 756 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 757 sock_reset_flag(sk, SOCK_DONE); 758 759 INIT_LIST_HEAD(&vsk->bound_table); 760 INIT_LIST_HEAD(&vsk->connected_table); 761 vsk->listener = NULL; 762 INIT_LIST_HEAD(&vsk->pending_links); 763 INIT_LIST_HEAD(&vsk->accept_queue); 764 vsk->rejected = false; 765 vsk->sent_request = false; 766 vsk->ignore_connecting_rst = false; 767 vsk->peer_shutdown = 0; 768 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 769 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 770 771 psk = parent ? vsock_sk(parent) : NULL; 772 if (parent) { 773 vsk->trusted = psk->trusted; 774 vsk->owner = get_cred(psk->owner); 775 vsk->connect_timeout = psk->connect_timeout; 776 vsk->buffer_size = psk->buffer_size; 777 vsk->buffer_min_size = psk->buffer_min_size; 778 vsk->buffer_max_size = psk->buffer_max_size; 779 security_sk_clone(parent, sk); 780 } else { 781 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN); 782 vsk->owner = get_current_cred(); 783 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 784 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE; 785 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE; 786 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE; 787 } 788 789 return sk; 790 } 791 792 static bool sock_type_connectible(u16 type) 793 { 794 return (type == SOCK_STREAM) || (type == SOCK_SEQPACKET); 795 } 796 797 static void __vsock_release(struct sock *sk, int level) 798 { 799 if (sk) { 800 struct sock *pending; 801 struct vsock_sock *vsk; 802 803 vsk = vsock_sk(sk); 804 pending = NULL; /* Compiler warning. */ 805 806 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 807 * version to avoid the warning "possible recursive locking 808 * detected". When "level" is 0, lock_sock_nested(sk, level) 809 * is the same as lock_sock(sk). 810 */ 811 lock_sock_nested(sk, level); 812 813 if (vsk->transport) 814 vsk->transport->release(vsk); 815 else if (sock_type_connectible(sk->sk_type)) 816 vsock_remove_sock(vsk); 817 818 sock_orphan(sk); 819 sk->sk_shutdown = SHUTDOWN_MASK; 820 821 skb_queue_purge(&sk->sk_receive_queue); 822 823 /* Clean up any sockets that never were accepted. */ 824 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 825 __vsock_release(pending, SINGLE_DEPTH_NESTING); 826 sock_put(pending); 827 } 828 829 release_sock(sk); 830 sock_put(sk); 831 } 832 } 833 834 static void vsock_sk_destruct(struct sock *sk) 835 { 836 struct vsock_sock *vsk = vsock_sk(sk); 837 838 vsock_deassign_transport(vsk); 839 840 /* When clearing these addresses, there's no need to set the family and 841 * possibly register the address family with the kernel. 842 */ 843 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 844 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 845 846 put_cred(vsk->owner); 847 } 848 849 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 850 { 851 int err; 852 853 err = sock_queue_rcv_skb(sk, skb); 854 if (err) 855 kfree_skb(skb); 856 857 return err; 858 } 859 860 struct sock *vsock_create_connected(struct sock *parent) 861 { 862 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL, 863 parent->sk_type, 0); 864 } 865 EXPORT_SYMBOL_GPL(vsock_create_connected); 866 867 s64 vsock_stream_has_data(struct vsock_sock *vsk) 868 { 869 return vsk->transport->stream_has_data(vsk); 870 } 871 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 872 873 s64 vsock_connectible_has_data(struct vsock_sock *vsk) 874 { 875 struct sock *sk = sk_vsock(vsk); 876 877 if (sk->sk_type == SOCK_SEQPACKET) 878 return vsk->transport->seqpacket_has_data(vsk); 879 else 880 return vsock_stream_has_data(vsk); 881 } 882 EXPORT_SYMBOL_GPL(vsock_connectible_has_data); 883 884 s64 vsock_stream_has_space(struct vsock_sock *vsk) 885 { 886 return vsk->transport->stream_has_space(vsk); 887 } 888 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 889 890 void vsock_data_ready(struct sock *sk) 891 { 892 struct vsock_sock *vsk = vsock_sk(sk); 893 894 if (vsock_stream_has_data(vsk) >= sk->sk_rcvlowat || 895 sock_flag(sk, SOCK_DONE)) 896 sk->sk_data_ready(sk); 897 } 898 EXPORT_SYMBOL_GPL(vsock_data_ready); 899 900 static int vsock_release(struct socket *sock) 901 { 902 __vsock_release(sock->sk, 0); 903 sock->sk = NULL; 904 sock->state = SS_FREE; 905 906 return 0; 907 } 908 909 static int 910 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 911 { 912 int err; 913 struct sock *sk; 914 struct sockaddr_vm *vm_addr; 915 916 sk = sock->sk; 917 918 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 919 return -EINVAL; 920 921 lock_sock(sk); 922 err = __vsock_bind(sk, vm_addr); 923 release_sock(sk); 924 925 return err; 926 } 927 928 static int vsock_getname(struct socket *sock, 929 struct sockaddr *addr, int peer) 930 { 931 int err; 932 struct sock *sk; 933 struct vsock_sock *vsk; 934 struct sockaddr_vm *vm_addr; 935 936 sk = sock->sk; 937 vsk = vsock_sk(sk); 938 err = 0; 939 940 lock_sock(sk); 941 942 if (peer) { 943 if (sock->state != SS_CONNECTED) { 944 err = -ENOTCONN; 945 goto out; 946 } 947 vm_addr = &vsk->remote_addr; 948 } else { 949 vm_addr = &vsk->local_addr; 950 } 951 952 if (!vm_addr) { 953 err = -EINVAL; 954 goto out; 955 } 956 957 /* sys_getsockname() and sys_getpeername() pass us a 958 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 959 * that macro is defined in socket.c instead of .h, so we hardcode its 960 * value here. 961 */ 962 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 963 memcpy(addr, vm_addr, sizeof(*vm_addr)); 964 err = sizeof(*vm_addr); 965 966 out: 967 release_sock(sk); 968 return err; 969 } 970 971 static int vsock_shutdown(struct socket *sock, int mode) 972 { 973 int err; 974 struct sock *sk; 975 976 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 977 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 978 * here like the other address families do. Note also that the 979 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 980 * which is what we want. 981 */ 982 mode++; 983 984 if ((mode & ~SHUTDOWN_MASK) || !mode) 985 return -EINVAL; 986 987 /* If this is a connection oriented socket and it is not connected then 988 * bail out immediately. If it is a DGRAM socket then we must first 989 * kick the socket so that it wakes up from any sleeping calls, for 990 * example recv(), and then afterwards return the error. 991 */ 992 993 sk = sock->sk; 994 995 lock_sock(sk); 996 if (sock->state == SS_UNCONNECTED) { 997 err = -ENOTCONN; 998 if (sock_type_connectible(sk->sk_type)) 999 goto out; 1000 } else { 1001 sock->state = SS_DISCONNECTING; 1002 err = 0; 1003 } 1004 1005 /* Receive and send shutdowns are treated alike. */ 1006 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 1007 if (mode) { 1008 sk->sk_shutdown |= mode; 1009 sk->sk_state_change(sk); 1010 1011 if (sock_type_connectible(sk->sk_type)) { 1012 sock_reset_flag(sk, SOCK_DONE); 1013 vsock_send_shutdown(sk, mode); 1014 } 1015 } 1016 1017 out: 1018 release_sock(sk); 1019 return err; 1020 } 1021 1022 static __poll_t vsock_poll(struct file *file, struct socket *sock, 1023 poll_table *wait) 1024 { 1025 struct sock *sk; 1026 __poll_t mask; 1027 struct vsock_sock *vsk; 1028 1029 sk = sock->sk; 1030 vsk = vsock_sk(sk); 1031 1032 poll_wait(file, sk_sleep(sk), wait); 1033 mask = 0; 1034 1035 if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue)) 1036 /* Signify that there has been an error on this socket. */ 1037 mask |= EPOLLERR; 1038 1039 /* INET sockets treat local write shutdown and peer write shutdown as a 1040 * case of EPOLLHUP set. 1041 */ 1042 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 1043 ((sk->sk_shutdown & SEND_SHUTDOWN) && 1044 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 1045 mask |= EPOLLHUP; 1046 } 1047 1048 if (sk->sk_shutdown & RCV_SHUTDOWN || 1049 vsk->peer_shutdown & SEND_SHUTDOWN) { 1050 mask |= EPOLLRDHUP; 1051 } 1052 1053 if (sock->type == SOCK_DGRAM) { 1054 /* For datagram sockets we can read if there is something in 1055 * the queue and write as long as the socket isn't shutdown for 1056 * sending. 1057 */ 1058 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 1059 (sk->sk_shutdown & RCV_SHUTDOWN)) { 1060 mask |= EPOLLIN | EPOLLRDNORM; 1061 } 1062 1063 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1064 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 1065 1066 } else if (sock_type_connectible(sk->sk_type)) { 1067 const struct vsock_transport *transport; 1068 1069 lock_sock(sk); 1070 1071 transport = vsk->transport; 1072 1073 /* Listening sockets that have connections in their accept 1074 * queue can be read. 1075 */ 1076 if (sk->sk_state == TCP_LISTEN 1077 && !vsock_is_accept_queue_empty(sk)) 1078 mask |= EPOLLIN | EPOLLRDNORM; 1079 1080 /* If there is something in the queue then we can read. */ 1081 if (transport && transport->stream_is_active(vsk) && 1082 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1083 bool data_ready_now = false; 1084 int target = sock_rcvlowat(sk, 0, INT_MAX); 1085 int ret = transport->notify_poll_in( 1086 vsk, target, &data_ready_now); 1087 if (ret < 0) { 1088 mask |= EPOLLERR; 1089 } else { 1090 if (data_ready_now) 1091 mask |= EPOLLIN | EPOLLRDNORM; 1092 1093 } 1094 } 1095 1096 /* Sockets whose connections have been closed, reset, or 1097 * terminated should also be considered read, and we check the 1098 * shutdown flag for that. 1099 */ 1100 if (sk->sk_shutdown & RCV_SHUTDOWN || 1101 vsk->peer_shutdown & SEND_SHUTDOWN) { 1102 mask |= EPOLLIN | EPOLLRDNORM; 1103 } 1104 1105 /* Connected sockets that can produce data can be written. */ 1106 if (transport && sk->sk_state == TCP_ESTABLISHED) { 1107 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1108 bool space_avail_now = false; 1109 int ret = transport->notify_poll_out( 1110 vsk, 1, &space_avail_now); 1111 if (ret < 0) { 1112 mask |= EPOLLERR; 1113 } else { 1114 if (space_avail_now) 1115 /* Remove EPOLLWRBAND since INET 1116 * sockets are not setting it. 1117 */ 1118 mask |= EPOLLOUT | EPOLLWRNORM; 1119 1120 } 1121 } 1122 } 1123 1124 /* Simulate INET socket poll behaviors, which sets 1125 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 1126 * but local send is not shutdown. 1127 */ 1128 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 1129 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1130 mask |= EPOLLOUT | EPOLLWRNORM; 1131 1132 } 1133 1134 release_sock(sk); 1135 } 1136 1137 return mask; 1138 } 1139 1140 static int vsock_read_skb(struct sock *sk, skb_read_actor_t read_actor) 1141 { 1142 struct vsock_sock *vsk = vsock_sk(sk); 1143 1144 return vsk->transport->read_skb(vsk, read_actor); 1145 } 1146 1147 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 1148 size_t len) 1149 { 1150 int err; 1151 struct sock *sk; 1152 struct vsock_sock *vsk; 1153 struct sockaddr_vm *remote_addr; 1154 const struct vsock_transport *transport; 1155 1156 if (msg->msg_flags & MSG_OOB) 1157 return -EOPNOTSUPP; 1158 1159 /* For now, MSG_DONTWAIT is always assumed... */ 1160 err = 0; 1161 sk = sock->sk; 1162 vsk = vsock_sk(sk); 1163 1164 lock_sock(sk); 1165 1166 transport = vsk->transport; 1167 1168 err = vsock_auto_bind(vsk); 1169 if (err) 1170 goto out; 1171 1172 1173 /* If the provided message contains an address, use that. Otherwise 1174 * fall back on the socket's remote handle (if it has been connected). 1175 */ 1176 if (msg->msg_name && 1177 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 1178 &remote_addr) == 0) { 1179 /* Ensure this address is of the right type and is a valid 1180 * destination. 1181 */ 1182 1183 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1184 remote_addr->svm_cid = transport->get_local_cid(); 1185 1186 if (!vsock_addr_bound(remote_addr)) { 1187 err = -EINVAL; 1188 goto out; 1189 } 1190 } else if (sock->state == SS_CONNECTED) { 1191 remote_addr = &vsk->remote_addr; 1192 1193 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1194 remote_addr->svm_cid = transport->get_local_cid(); 1195 1196 /* XXX Should connect() or this function ensure remote_addr is 1197 * bound? 1198 */ 1199 if (!vsock_addr_bound(&vsk->remote_addr)) { 1200 err = -EINVAL; 1201 goto out; 1202 } 1203 } else { 1204 err = -EINVAL; 1205 goto out; 1206 } 1207 1208 if (!transport->dgram_allow(remote_addr->svm_cid, 1209 remote_addr->svm_port)) { 1210 err = -EINVAL; 1211 goto out; 1212 } 1213 1214 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1215 1216 out: 1217 release_sock(sk); 1218 return err; 1219 } 1220 1221 static int vsock_dgram_connect(struct socket *sock, 1222 struct sockaddr *addr, int addr_len, int flags) 1223 { 1224 int err; 1225 struct sock *sk; 1226 struct vsock_sock *vsk; 1227 struct sockaddr_vm *remote_addr; 1228 1229 sk = sock->sk; 1230 vsk = vsock_sk(sk); 1231 1232 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1233 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1234 lock_sock(sk); 1235 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1236 VMADDR_PORT_ANY); 1237 sock->state = SS_UNCONNECTED; 1238 release_sock(sk); 1239 return 0; 1240 } else if (err != 0) 1241 return -EINVAL; 1242 1243 lock_sock(sk); 1244 1245 err = vsock_auto_bind(vsk); 1246 if (err) 1247 goto out; 1248 1249 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1250 remote_addr->svm_port)) { 1251 err = -EINVAL; 1252 goto out; 1253 } 1254 1255 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1256 sock->state = SS_CONNECTED; 1257 1258 /* sock map disallows redirection of non-TCP sockets with sk_state != 1259 * TCP_ESTABLISHED (see sock_map_redirect_allowed()), so we set 1260 * TCP_ESTABLISHED here to allow redirection of connected vsock dgrams. 1261 * 1262 * This doesn't seem to be abnormal state for datagram sockets, as the 1263 * same approach can be see in other datagram socket types as well 1264 * (such as unix sockets). 1265 */ 1266 sk->sk_state = TCP_ESTABLISHED; 1267 1268 out: 1269 release_sock(sk); 1270 return err; 1271 } 1272 1273 int __vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1274 size_t len, int flags) 1275 { 1276 struct sock *sk = sock->sk; 1277 struct vsock_sock *vsk = vsock_sk(sk); 1278 1279 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1280 } 1281 1282 int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1283 size_t len, int flags) 1284 { 1285 #ifdef CONFIG_BPF_SYSCALL 1286 struct sock *sk = sock->sk; 1287 const struct proto *prot; 1288 1289 prot = READ_ONCE(sk->sk_prot); 1290 if (prot != &vsock_proto) 1291 return prot->recvmsg(sk, msg, len, flags, NULL); 1292 #endif 1293 1294 return __vsock_dgram_recvmsg(sock, msg, len, flags); 1295 } 1296 EXPORT_SYMBOL_GPL(vsock_dgram_recvmsg); 1297 1298 static const struct proto_ops vsock_dgram_ops = { 1299 .family = PF_VSOCK, 1300 .owner = THIS_MODULE, 1301 .release = vsock_release, 1302 .bind = vsock_bind, 1303 .connect = vsock_dgram_connect, 1304 .socketpair = sock_no_socketpair, 1305 .accept = sock_no_accept, 1306 .getname = vsock_getname, 1307 .poll = vsock_poll, 1308 .ioctl = sock_no_ioctl, 1309 .listen = sock_no_listen, 1310 .shutdown = vsock_shutdown, 1311 .sendmsg = vsock_dgram_sendmsg, 1312 .recvmsg = vsock_dgram_recvmsg, 1313 .mmap = sock_no_mmap, 1314 .read_skb = vsock_read_skb, 1315 }; 1316 1317 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1318 { 1319 const struct vsock_transport *transport = vsk->transport; 1320 1321 if (!transport || !transport->cancel_pkt) 1322 return -EOPNOTSUPP; 1323 1324 return transport->cancel_pkt(vsk); 1325 } 1326 1327 static void vsock_connect_timeout(struct work_struct *work) 1328 { 1329 struct sock *sk; 1330 struct vsock_sock *vsk; 1331 1332 vsk = container_of(work, struct vsock_sock, connect_work.work); 1333 sk = sk_vsock(vsk); 1334 1335 lock_sock(sk); 1336 if (sk->sk_state == TCP_SYN_SENT && 1337 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1338 sk->sk_state = TCP_CLOSE; 1339 sk->sk_socket->state = SS_UNCONNECTED; 1340 sk->sk_err = ETIMEDOUT; 1341 sk_error_report(sk); 1342 vsock_transport_cancel_pkt(vsk); 1343 } 1344 release_sock(sk); 1345 1346 sock_put(sk); 1347 } 1348 1349 static int vsock_connect(struct socket *sock, struct sockaddr *addr, 1350 int addr_len, int flags) 1351 { 1352 int err; 1353 struct sock *sk; 1354 struct vsock_sock *vsk; 1355 const struct vsock_transport *transport; 1356 struct sockaddr_vm *remote_addr; 1357 long timeout; 1358 DEFINE_WAIT(wait); 1359 1360 err = 0; 1361 sk = sock->sk; 1362 vsk = vsock_sk(sk); 1363 1364 lock_sock(sk); 1365 1366 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1367 switch (sock->state) { 1368 case SS_CONNECTED: 1369 err = -EISCONN; 1370 goto out; 1371 case SS_DISCONNECTING: 1372 err = -EINVAL; 1373 goto out; 1374 case SS_CONNECTING: 1375 /* This continues on so we can move sock into the SS_CONNECTED 1376 * state once the connection has completed (at which point err 1377 * will be set to zero also). Otherwise, we will either wait 1378 * for the connection or return -EALREADY should this be a 1379 * non-blocking call. 1380 */ 1381 err = -EALREADY; 1382 if (flags & O_NONBLOCK) 1383 goto out; 1384 break; 1385 default: 1386 if ((sk->sk_state == TCP_LISTEN) || 1387 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1388 err = -EINVAL; 1389 goto out; 1390 } 1391 1392 /* Set the remote address that we are connecting to. */ 1393 memcpy(&vsk->remote_addr, remote_addr, 1394 sizeof(vsk->remote_addr)); 1395 1396 err = vsock_assign_transport(vsk, NULL); 1397 if (err) 1398 goto out; 1399 1400 transport = vsk->transport; 1401 1402 /* The hypervisor and well-known contexts do not have socket 1403 * endpoints. 1404 */ 1405 if (!transport || 1406 !transport->stream_allow(remote_addr->svm_cid, 1407 remote_addr->svm_port)) { 1408 err = -ENETUNREACH; 1409 goto out; 1410 } 1411 1412 if (vsock_msgzerocopy_allow(transport)) { 1413 set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1414 } else if (sock_flag(sk, SOCK_ZEROCOPY)) { 1415 /* If this option was set before 'connect()', 1416 * when transport was unknown, check that this 1417 * feature is supported here. 1418 */ 1419 err = -EOPNOTSUPP; 1420 goto out; 1421 } 1422 1423 err = vsock_auto_bind(vsk); 1424 if (err) 1425 goto out; 1426 1427 sk->sk_state = TCP_SYN_SENT; 1428 1429 err = transport->connect(vsk); 1430 if (err < 0) 1431 goto out; 1432 1433 /* Mark sock as connecting and set the error code to in 1434 * progress in case this is a non-blocking connect. 1435 */ 1436 sock->state = SS_CONNECTING; 1437 err = -EINPROGRESS; 1438 } 1439 1440 /* The receive path will handle all communication until we are able to 1441 * enter the connected state. Here we wait for the connection to be 1442 * completed or a notification of an error. 1443 */ 1444 timeout = vsk->connect_timeout; 1445 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1446 1447 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1448 if (flags & O_NONBLOCK) { 1449 /* If we're not going to block, we schedule a timeout 1450 * function to generate a timeout on the connection 1451 * attempt, in case the peer doesn't respond in a 1452 * timely manner. We hold on to the socket until the 1453 * timeout fires. 1454 */ 1455 sock_hold(sk); 1456 1457 /* If the timeout function is already scheduled, 1458 * reschedule it, then ungrab the socket refcount to 1459 * keep it balanced. 1460 */ 1461 if (mod_delayed_work(system_wq, &vsk->connect_work, 1462 timeout)) 1463 sock_put(sk); 1464 1465 /* Skip ahead to preserve error code set above. */ 1466 goto out_wait; 1467 } 1468 1469 release_sock(sk); 1470 timeout = schedule_timeout(timeout); 1471 lock_sock(sk); 1472 1473 if (signal_pending(current)) { 1474 err = sock_intr_errno(timeout); 1475 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; 1476 sock->state = SS_UNCONNECTED; 1477 vsock_transport_cancel_pkt(vsk); 1478 vsock_remove_connected(vsk); 1479 goto out_wait; 1480 } else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) { 1481 err = -ETIMEDOUT; 1482 sk->sk_state = TCP_CLOSE; 1483 sock->state = SS_UNCONNECTED; 1484 vsock_transport_cancel_pkt(vsk); 1485 goto out_wait; 1486 } 1487 1488 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1489 } 1490 1491 if (sk->sk_err) { 1492 err = -sk->sk_err; 1493 sk->sk_state = TCP_CLOSE; 1494 sock->state = SS_UNCONNECTED; 1495 } else { 1496 err = 0; 1497 } 1498 1499 out_wait: 1500 finish_wait(sk_sleep(sk), &wait); 1501 out: 1502 release_sock(sk); 1503 return err; 1504 } 1505 1506 static int vsock_accept(struct socket *sock, struct socket *newsock, 1507 struct proto_accept_arg *arg) 1508 { 1509 struct sock *listener; 1510 int err; 1511 struct sock *connected; 1512 struct vsock_sock *vconnected; 1513 long timeout; 1514 DEFINE_WAIT(wait); 1515 1516 err = 0; 1517 listener = sock->sk; 1518 1519 lock_sock(listener); 1520 1521 if (!sock_type_connectible(sock->type)) { 1522 err = -EOPNOTSUPP; 1523 goto out; 1524 } 1525 1526 if (listener->sk_state != TCP_LISTEN) { 1527 err = -EINVAL; 1528 goto out; 1529 } 1530 1531 /* Wait for children sockets to appear; these are the new sockets 1532 * created upon connection establishment. 1533 */ 1534 timeout = sock_rcvtimeo(listener, arg->flags & O_NONBLOCK); 1535 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1536 1537 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1538 listener->sk_err == 0) { 1539 release_sock(listener); 1540 timeout = schedule_timeout(timeout); 1541 finish_wait(sk_sleep(listener), &wait); 1542 lock_sock(listener); 1543 1544 if (signal_pending(current)) { 1545 err = sock_intr_errno(timeout); 1546 goto out; 1547 } else if (timeout == 0) { 1548 err = -EAGAIN; 1549 goto out; 1550 } 1551 1552 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1553 } 1554 finish_wait(sk_sleep(listener), &wait); 1555 1556 if (listener->sk_err) 1557 err = -listener->sk_err; 1558 1559 if (connected) { 1560 sk_acceptq_removed(listener); 1561 1562 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1563 vconnected = vsock_sk(connected); 1564 1565 /* If the listener socket has received an error, then we should 1566 * reject this socket and return. Note that we simply mark the 1567 * socket rejected, drop our reference, and let the cleanup 1568 * function handle the cleanup; the fact that we found it in 1569 * the listener's accept queue guarantees that the cleanup 1570 * function hasn't run yet. 1571 */ 1572 if (err) { 1573 vconnected->rejected = true; 1574 } else { 1575 newsock->state = SS_CONNECTED; 1576 sock_graft(connected, newsock); 1577 if (vsock_msgzerocopy_allow(vconnected->transport)) 1578 set_bit(SOCK_SUPPORT_ZC, 1579 &connected->sk_socket->flags); 1580 } 1581 1582 release_sock(connected); 1583 sock_put(connected); 1584 } 1585 1586 out: 1587 release_sock(listener); 1588 return err; 1589 } 1590 1591 static int vsock_listen(struct socket *sock, int backlog) 1592 { 1593 int err; 1594 struct sock *sk; 1595 struct vsock_sock *vsk; 1596 1597 sk = sock->sk; 1598 1599 lock_sock(sk); 1600 1601 if (!sock_type_connectible(sk->sk_type)) { 1602 err = -EOPNOTSUPP; 1603 goto out; 1604 } 1605 1606 if (sock->state != SS_UNCONNECTED) { 1607 err = -EINVAL; 1608 goto out; 1609 } 1610 1611 vsk = vsock_sk(sk); 1612 1613 if (!vsock_addr_bound(&vsk->local_addr)) { 1614 err = -EINVAL; 1615 goto out; 1616 } 1617 1618 sk->sk_max_ack_backlog = backlog; 1619 sk->sk_state = TCP_LISTEN; 1620 1621 err = 0; 1622 1623 out: 1624 release_sock(sk); 1625 return err; 1626 } 1627 1628 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1629 const struct vsock_transport *transport, 1630 u64 val) 1631 { 1632 if (val > vsk->buffer_max_size) 1633 val = vsk->buffer_max_size; 1634 1635 if (val < vsk->buffer_min_size) 1636 val = vsk->buffer_min_size; 1637 1638 if (val != vsk->buffer_size && 1639 transport && transport->notify_buffer_size) 1640 transport->notify_buffer_size(vsk, &val); 1641 1642 vsk->buffer_size = val; 1643 } 1644 1645 static int vsock_connectible_setsockopt(struct socket *sock, 1646 int level, 1647 int optname, 1648 sockptr_t optval, 1649 unsigned int optlen) 1650 { 1651 int err; 1652 struct sock *sk; 1653 struct vsock_sock *vsk; 1654 const struct vsock_transport *transport; 1655 u64 val; 1656 1657 if (level != AF_VSOCK && level != SOL_SOCKET) 1658 return -ENOPROTOOPT; 1659 1660 #define COPY_IN(_v) \ 1661 do { \ 1662 if (optlen < sizeof(_v)) { \ 1663 err = -EINVAL; \ 1664 goto exit; \ 1665 } \ 1666 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1667 err = -EFAULT; \ 1668 goto exit; \ 1669 } \ 1670 } while (0) 1671 1672 err = 0; 1673 sk = sock->sk; 1674 vsk = vsock_sk(sk); 1675 1676 lock_sock(sk); 1677 1678 transport = vsk->transport; 1679 1680 if (level == SOL_SOCKET) { 1681 int zerocopy; 1682 1683 if (optname != SO_ZEROCOPY) { 1684 release_sock(sk); 1685 return sock_setsockopt(sock, level, optname, optval, optlen); 1686 } 1687 1688 /* Use 'int' type here, because variable to 1689 * set this option usually has this type. 1690 */ 1691 COPY_IN(zerocopy); 1692 1693 if (zerocopy < 0 || zerocopy > 1) { 1694 err = -EINVAL; 1695 goto exit; 1696 } 1697 1698 if (transport && !vsock_msgzerocopy_allow(transport)) { 1699 err = -EOPNOTSUPP; 1700 goto exit; 1701 } 1702 1703 sock_valbool_flag(sk, SOCK_ZEROCOPY, zerocopy); 1704 goto exit; 1705 } 1706 1707 switch (optname) { 1708 case SO_VM_SOCKETS_BUFFER_SIZE: 1709 COPY_IN(val); 1710 vsock_update_buffer_size(vsk, transport, val); 1711 break; 1712 1713 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1714 COPY_IN(val); 1715 vsk->buffer_max_size = val; 1716 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1717 break; 1718 1719 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1720 COPY_IN(val); 1721 vsk->buffer_min_size = val; 1722 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1723 break; 1724 1725 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1726 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: { 1727 struct __kernel_sock_timeval tv; 1728 1729 err = sock_copy_user_timeval(&tv, optval, optlen, 1730 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1731 if (err) 1732 break; 1733 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1734 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1735 vsk->connect_timeout = tv.tv_sec * HZ + 1736 DIV_ROUND_UP((unsigned long)tv.tv_usec, (USEC_PER_SEC / HZ)); 1737 if (vsk->connect_timeout == 0) 1738 vsk->connect_timeout = 1739 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1740 1741 } else { 1742 err = -ERANGE; 1743 } 1744 break; 1745 } 1746 1747 default: 1748 err = -ENOPROTOOPT; 1749 break; 1750 } 1751 1752 #undef COPY_IN 1753 1754 exit: 1755 release_sock(sk); 1756 return err; 1757 } 1758 1759 static int vsock_connectible_getsockopt(struct socket *sock, 1760 int level, int optname, 1761 char __user *optval, 1762 int __user *optlen) 1763 { 1764 struct sock *sk = sock->sk; 1765 struct vsock_sock *vsk = vsock_sk(sk); 1766 1767 union { 1768 u64 val64; 1769 struct old_timeval32 tm32; 1770 struct __kernel_old_timeval tm; 1771 struct __kernel_sock_timeval stm; 1772 } v; 1773 1774 int lv = sizeof(v.val64); 1775 int len; 1776 1777 if (level != AF_VSOCK) 1778 return -ENOPROTOOPT; 1779 1780 if (get_user(len, optlen)) 1781 return -EFAULT; 1782 1783 memset(&v, 0, sizeof(v)); 1784 1785 switch (optname) { 1786 case SO_VM_SOCKETS_BUFFER_SIZE: 1787 v.val64 = vsk->buffer_size; 1788 break; 1789 1790 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1791 v.val64 = vsk->buffer_max_size; 1792 break; 1793 1794 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1795 v.val64 = vsk->buffer_min_size; 1796 break; 1797 1798 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1799 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: 1800 lv = sock_get_timeout(vsk->connect_timeout, &v, 1801 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1802 break; 1803 1804 default: 1805 return -ENOPROTOOPT; 1806 } 1807 1808 if (len < lv) 1809 return -EINVAL; 1810 if (len > lv) 1811 len = lv; 1812 if (copy_to_user(optval, &v, len)) 1813 return -EFAULT; 1814 1815 if (put_user(len, optlen)) 1816 return -EFAULT; 1817 1818 return 0; 1819 } 1820 1821 static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, 1822 size_t len) 1823 { 1824 struct sock *sk; 1825 struct vsock_sock *vsk; 1826 const struct vsock_transport *transport; 1827 ssize_t total_written; 1828 long timeout; 1829 int err; 1830 struct vsock_transport_send_notify_data send_data; 1831 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1832 1833 sk = sock->sk; 1834 vsk = vsock_sk(sk); 1835 total_written = 0; 1836 err = 0; 1837 1838 if (msg->msg_flags & MSG_OOB) 1839 return -EOPNOTSUPP; 1840 1841 lock_sock(sk); 1842 1843 transport = vsk->transport; 1844 1845 /* Callers should not provide a destination with connection oriented 1846 * sockets. 1847 */ 1848 if (msg->msg_namelen) { 1849 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1850 goto out; 1851 } 1852 1853 /* Send data only if both sides are not shutdown in the direction. */ 1854 if (sk->sk_shutdown & SEND_SHUTDOWN || 1855 vsk->peer_shutdown & RCV_SHUTDOWN) { 1856 err = -EPIPE; 1857 goto out; 1858 } 1859 1860 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1861 !vsock_addr_bound(&vsk->local_addr)) { 1862 err = -ENOTCONN; 1863 goto out; 1864 } 1865 1866 if (!vsock_addr_bound(&vsk->remote_addr)) { 1867 err = -EDESTADDRREQ; 1868 goto out; 1869 } 1870 1871 if (msg->msg_flags & MSG_ZEROCOPY && 1872 !vsock_msgzerocopy_allow(transport)) { 1873 err = -EOPNOTSUPP; 1874 goto out; 1875 } 1876 1877 /* Wait for room in the produce queue to enqueue our user's data. */ 1878 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1879 1880 err = transport->notify_send_init(vsk, &send_data); 1881 if (err < 0) 1882 goto out; 1883 1884 while (total_written < len) { 1885 ssize_t written; 1886 1887 add_wait_queue(sk_sleep(sk), &wait); 1888 while (vsock_stream_has_space(vsk) == 0 && 1889 sk->sk_err == 0 && 1890 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1891 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1892 1893 /* Don't wait for non-blocking sockets. */ 1894 if (timeout == 0) { 1895 err = -EAGAIN; 1896 remove_wait_queue(sk_sleep(sk), &wait); 1897 goto out_err; 1898 } 1899 1900 err = transport->notify_send_pre_block(vsk, &send_data); 1901 if (err < 0) { 1902 remove_wait_queue(sk_sleep(sk), &wait); 1903 goto out_err; 1904 } 1905 1906 release_sock(sk); 1907 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1908 lock_sock(sk); 1909 if (signal_pending(current)) { 1910 err = sock_intr_errno(timeout); 1911 remove_wait_queue(sk_sleep(sk), &wait); 1912 goto out_err; 1913 } else if (timeout == 0) { 1914 err = -EAGAIN; 1915 remove_wait_queue(sk_sleep(sk), &wait); 1916 goto out_err; 1917 } 1918 } 1919 remove_wait_queue(sk_sleep(sk), &wait); 1920 1921 /* These checks occur both as part of and after the loop 1922 * conditional since we need to check before and after 1923 * sleeping. 1924 */ 1925 if (sk->sk_err) { 1926 err = -sk->sk_err; 1927 goto out_err; 1928 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1929 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1930 err = -EPIPE; 1931 goto out_err; 1932 } 1933 1934 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1935 if (err < 0) 1936 goto out_err; 1937 1938 /* Note that enqueue will only write as many bytes as are free 1939 * in the produce queue, so we don't need to ensure len is 1940 * smaller than the queue size. It is the caller's 1941 * responsibility to check how many bytes we were able to send. 1942 */ 1943 1944 if (sk->sk_type == SOCK_SEQPACKET) { 1945 written = transport->seqpacket_enqueue(vsk, 1946 msg, len - total_written); 1947 } else { 1948 written = transport->stream_enqueue(vsk, 1949 msg, len - total_written); 1950 } 1951 1952 if (written < 0) { 1953 err = written; 1954 goto out_err; 1955 } 1956 1957 total_written += written; 1958 1959 err = transport->notify_send_post_enqueue( 1960 vsk, written, &send_data); 1961 if (err < 0) 1962 goto out_err; 1963 1964 } 1965 1966 out_err: 1967 if (total_written > 0) { 1968 /* Return number of written bytes only if: 1969 * 1) SOCK_STREAM socket. 1970 * 2) SOCK_SEQPACKET socket when whole buffer is sent. 1971 */ 1972 if (sk->sk_type == SOCK_STREAM || total_written == len) 1973 err = total_written; 1974 } 1975 out: 1976 if (sk->sk_type == SOCK_STREAM) 1977 err = sk_stream_error(sk, msg->msg_flags, err); 1978 1979 release_sock(sk); 1980 return err; 1981 } 1982 1983 static int vsock_connectible_wait_data(struct sock *sk, 1984 struct wait_queue_entry *wait, 1985 long timeout, 1986 struct vsock_transport_recv_notify_data *recv_data, 1987 size_t target) 1988 { 1989 const struct vsock_transport *transport; 1990 struct vsock_sock *vsk; 1991 s64 data; 1992 int err; 1993 1994 vsk = vsock_sk(sk); 1995 err = 0; 1996 transport = vsk->transport; 1997 1998 while (1) { 1999 prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); 2000 data = vsock_connectible_has_data(vsk); 2001 if (data != 0) 2002 break; 2003 2004 if (sk->sk_err != 0 || 2005 (sk->sk_shutdown & RCV_SHUTDOWN) || 2006 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 2007 break; 2008 } 2009 2010 /* Don't wait for non-blocking sockets. */ 2011 if (timeout == 0) { 2012 err = -EAGAIN; 2013 break; 2014 } 2015 2016 if (recv_data) { 2017 err = transport->notify_recv_pre_block(vsk, target, recv_data); 2018 if (err < 0) 2019 break; 2020 } 2021 2022 release_sock(sk); 2023 timeout = schedule_timeout(timeout); 2024 lock_sock(sk); 2025 2026 if (signal_pending(current)) { 2027 err = sock_intr_errno(timeout); 2028 break; 2029 } else if (timeout == 0) { 2030 err = -EAGAIN; 2031 break; 2032 } 2033 } 2034 2035 finish_wait(sk_sleep(sk), wait); 2036 2037 if (err) 2038 return err; 2039 2040 /* Internal transport error when checking for available 2041 * data. XXX This should be changed to a connection 2042 * reset in a later change. 2043 */ 2044 if (data < 0) 2045 return -ENOMEM; 2046 2047 return data; 2048 } 2049 2050 static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, 2051 size_t len, int flags) 2052 { 2053 struct vsock_transport_recv_notify_data recv_data; 2054 const struct vsock_transport *transport; 2055 struct vsock_sock *vsk; 2056 ssize_t copied; 2057 size_t target; 2058 long timeout; 2059 int err; 2060 2061 DEFINE_WAIT(wait); 2062 2063 vsk = vsock_sk(sk); 2064 transport = vsk->transport; 2065 2066 /* We must not copy less than target bytes into the user's buffer 2067 * before returning successfully, so we wait for the consume queue to 2068 * have that much data to consume before dequeueing. Note that this 2069 * makes it impossible to handle cases where target is greater than the 2070 * queue size. 2071 */ 2072 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 2073 if (target >= transport->stream_rcvhiwat(vsk)) { 2074 err = -ENOMEM; 2075 goto out; 2076 } 2077 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2078 copied = 0; 2079 2080 err = transport->notify_recv_init(vsk, target, &recv_data); 2081 if (err < 0) 2082 goto out; 2083 2084 2085 while (1) { 2086 ssize_t read; 2087 2088 err = vsock_connectible_wait_data(sk, &wait, timeout, 2089 &recv_data, target); 2090 if (err <= 0) 2091 break; 2092 2093 err = transport->notify_recv_pre_dequeue(vsk, target, 2094 &recv_data); 2095 if (err < 0) 2096 break; 2097 2098 read = transport->stream_dequeue(vsk, msg, len - copied, flags); 2099 if (read < 0) { 2100 err = read; 2101 break; 2102 } 2103 2104 copied += read; 2105 2106 err = transport->notify_recv_post_dequeue(vsk, target, read, 2107 !(flags & MSG_PEEK), &recv_data); 2108 if (err < 0) 2109 goto out; 2110 2111 if (read >= target || flags & MSG_PEEK) 2112 break; 2113 2114 target -= read; 2115 } 2116 2117 if (sk->sk_err) 2118 err = -sk->sk_err; 2119 else if (sk->sk_shutdown & RCV_SHUTDOWN) 2120 err = 0; 2121 2122 if (copied > 0) 2123 err = copied; 2124 2125 out: 2126 return err; 2127 } 2128 2129 static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, 2130 size_t len, int flags) 2131 { 2132 const struct vsock_transport *transport; 2133 struct vsock_sock *vsk; 2134 ssize_t msg_len; 2135 long timeout; 2136 int err = 0; 2137 DEFINE_WAIT(wait); 2138 2139 vsk = vsock_sk(sk); 2140 transport = vsk->transport; 2141 2142 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2143 2144 err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0); 2145 if (err <= 0) 2146 goto out; 2147 2148 msg_len = transport->seqpacket_dequeue(vsk, msg, flags); 2149 2150 if (msg_len < 0) { 2151 err = msg_len; 2152 goto out; 2153 } 2154 2155 if (sk->sk_err) { 2156 err = -sk->sk_err; 2157 } else if (sk->sk_shutdown & RCV_SHUTDOWN) { 2158 err = 0; 2159 } else { 2160 /* User sets MSG_TRUNC, so return real length of 2161 * packet. 2162 */ 2163 if (flags & MSG_TRUNC) 2164 err = msg_len; 2165 else 2166 err = len - msg_data_left(msg); 2167 2168 /* Always set MSG_TRUNC if real length of packet is 2169 * bigger than user's buffer. 2170 */ 2171 if (msg_len > len) 2172 msg->msg_flags |= MSG_TRUNC; 2173 } 2174 2175 out: 2176 return err; 2177 } 2178 2179 int 2180 __vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2181 int flags) 2182 { 2183 struct sock *sk; 2184 struct vsock_sock *vsk; 2185 const struct vsock_transport *transport; 2186 int err; 2187 2188 sk = sock->sk; 2189 2190 if (unlikely(flags & MSG_ERRQUEUE)) 2191 return sock_recv_errqueue(sk, msg, len, SOL_VSOCK, VSOCK_RECVERR); 2192 2193 vsk = vsock_sk(sk); 2194 err = 0; 2195 2196 lock_sock(sk); 2197 2198 transport = vsk->transport; 2199 2200 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 2201 /* Recvmsg is supposed to return 0 if a peer performs an 2202 * orderly shutdown. Differentiate between that case and when a 2203 * peer has not connected or a local shutdown occurred with the 2204 * SOCK_DONE flag. 2205 */ 2206 if (sock_flag(sk, SOCK_DONE)) 2207 err = 0; 2208 else 2209 err = -ENOTCONN; 2210 2211 goto out; 2212 } 2213 2214 if (flags & MSG_OOB) { 2215 err = -EOPNOTSUPP; 2216 goto out; 2217 } 2218 2219 /* We don't check peer_shutdown flag here since peer may actually shut 2220 * down, but there can be data in the queue that a local socket can 2221 * receive. 2222 */ 2223 if (sk->sk_shutdown & RCV_SHUTDOWN) { 2224 err = 0; 2225 goto out; 2226 } 2227 2228 /* It is valid on Linux to pass in a zero-length receive buffer. This 2229 * is not an error. We may as well bail out now. 2230 */ 2231 if (!len) { 2232 err = 0; 2233 goto out; 2234 } 2235 2236 if (sk->sk_type == SOCK_STREAM) 2237 err = __vsock_stream_recvmsg(sk, msg, len, flags); 2238 else 2239 err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); 2240 2241 out: 2242 release_sock(sk); 2243 return err; 2244 } 2245 2246 int 2247 vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2248 int flags) 2249 { 2250 #ifdef CONFIG_BPF_SYSCALL 2251 struct sock *sk = sock->sk; 2252 const struct proto *prot; 2253 2254 prot = READ_ONCE(sk->sk_prot); 2255 if (prot != &vsock_proto) 2256 return prot->recvmsg(sk, msg, len, flags, NULL); 2257 #endif 2258 2259 return __vsock_connectible_recvmsg(sock, msg, len, flags); 2260 } 2261 EXPORT_SYMBOL_GPL(vsock_connectible_recvmsg); 2262 2263 static int vsock_set_rcvlowat(struct sock *sk, int val) 2264 { 2265 const struct vsock_transport *transport; 2266 struct vsock_sock *vsk; 2267 2268 vsk = vsock_sk(sk); 2269 2270 if (val > vsk->buffer_size) 2271 return -EINVAL; 2272 2273 transport = vsk->transport; 2274 2275 if (transport && transport->notify_set_rcvlowat) { 2276 int err; 2277 2278 err = transport->notify_set_rcvlowat(vsk, val); 2279 if (err) 2280 return err; 2281 } 2282 2283 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 2284 return 0; 2285 } 2286 2287 static const struct proto_ops vsock_stream_ops = { 2288 .family = PF_VSOCK, 2289 .owner = THIS_MODULE, 2290 .release = vsock_release, 2291 .bind = vsock_bind, 2292 .connect = vsock_connect, 2293 .socketpair = sock_no_socketpair, 2294 .accept = vsock_accept, 2295 .getname = vsock_getname, 2296 .poll = vsock_poll, 2297 .ioctl = sock_no_ioctl, 2298 .listen = vsock_listen, 2299 .shutdown = vsock_shutdown, 2300 .setsockopt = vsock_connectible_setsockopt, 2301 .getsockopt = vsock_connectible_getsockopt, 2302 .sendmsg = vsock_connectible_sendmsg, 2303 .recvmsg = vsock_connectible_recvmsg, 2304 .mmap = sock_no_mmap, 2305 .set_rcvlowat = vsock_set_rcvlowat, 2306 .read_skb = vsock_read_skb, 2307 }; 2308 2309 static const struct proto_ops vsock_seqpacket_ops = { 2310 .family = PF_VSOCK, 2311 .owner = THIS_MODULE, 2312 .release = vsock_release, 2313 .bind = vsock_bind, 2314 .connect = vsock_connect, 2315 .socketpair = sock_no_socketpair, 2316 .accept = vsock_accept, 2317 .getname = vsock_getname, 2318 .poll = vsock_poll, 2319 .ioctl = sock_no_ioctl, 2320 .listen = vsock_listen, 2321 .shutdown = vsock_shutdown, 2322 .setsockopt = vsock_connectible_setsockopt, 2323 .getsockopt = vsock_connectible_getsockopt, 2324 .sendmsg = vsock_connectible_sendmsg, 2325 .recvmsg = vsock_connectible_recvmsg, 2326 .mmap = sock_no_mmap, 2327 .read_skb = vsock_read_skb, 2328 }; 2329 2330 static int vsock_create(struct net *net, struct socket *sock, 2331 int protocol, int kern) 2332 { 2333 struct vsock_sock *vsk; 2334 struct sock *sk; 2335 int ret; 2336 2337 if (!sock) 2338 return -EINVAL; 2339 2340 if (protocol && protocol != PF_VSOCK) 2341 return -EPROTONOSUPPORT; 2342 2343 switch (sock->type) { 2344 case SOCK_DGRAM: 2345 sock->ops = &vsock_dgram_ops; 2346 break; 2347 case SOCK_STREAM: 2348 sock->ops = &vsock_stream_ops; 2349 break; 2350 case SOCK_SEQPACKET: 2351 sock->ops = &vsock_seqpacket_ops; 2352 break; 2353 default: 2354 return -ESOCKTNOSUPPORT; 2355 } 2356 2357 sock->state = SS_UNCONNECTED; 2358 2359 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2360 if (!sk) 2361 return -ENOMEM; 2362 2363 vsk = vsock_sk(sk); 2364 2365 if (sock->type == SOCK_DGRAM) { 2366 ret = vsock_assign_transport(vsk, NULL); 2367 if (ret < 0) { 2368 sock_put(sk); 2369 return ret; 2370 } 2371 } 2372 2373 /* SOCK_DGRAM doesn't have 'setsockopt' callback set in its 2374 * proto_ops, so there is no handler for custom logic. 2375 */ 2376 if (sock_type_connectible(sock->type)) 2377 set_bit(SOCK_CUSTOM_SOCKOPT, &sk->sk_socket->flags); 2378 2379 vsock_insert_unbound(vsk); 2380 2381 return 0; 2382 } 2383 2384 static const struct net_proto_family vsock_family_ops = { 2385 .family = AF_VSOCK, 2386 .create = vsock_create, 2387 .owner = THIS_MODULE, 2388 }; 2389 2390 static long vsock_dev_do_ioctl(struct file *filp, 2391 unsigned int cmd, void __user *ptr) 2392 { 2393 u32 __user *p = ptr; 2394 u32 cid = VMADDR_CID_ANY; 2395 int retval = 0; 2396 2397 switch (cmd) { 2398 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2399 /* To be compatible with the VMCI behavior, we prioritize the 2400 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2401 */ 2402 if (transport_g2h) 2403 cid = transport_g2h->get_local_cid(); 2404 else if (transport_h2g) 2405 cid = transport_h2g->get_local_cid(); 2406 2407 if (put_user(cid, p) != 0) 2408 retval = -EFAULT; 2409 break; 2410 2411 default: 2412 retval = -ENOIOCTLCMD; 2413 } 2414 2415 return retval; 2416 } 2417 2418 static long vsock_dev_ioctl(struct file *filp, 2419 unsigned int cmd, unsigned long arg) 2420 { 2421 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2422 } 2423 2424 #ifdef CONFIG_COMPAT 2425 static long vsock_dev_compat_ioctl(struct file *filp, 2426 unsigned int cmd, unsigned long arg) 2427 { 2428 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2429 } 2430 #endif 2431 2432 static const struct file_operations vsock_device_ops = { 2433 .owner = THIS_MODULE, 2434 .unlocked_ioctl = vsock_dev_ioctl, 2435 #ifdef CONFIG_COMPAT 2436 .compat_ioctl = vsock_dev_compat_ioctl, 2437 #endif 2438 .open = nonseekable_open, 2439 }; 2440 2441 static struct miscdevice vsock_device = { 2442 .name = "vsock", 2443 .fops = &vsock_device_ops, 2444 }; 2445 2446 static int __init vsock_init(void) 2447 { 2448 int err = 0; 2449 2450 vsock_init_tables(); 2451 2452 vsock_proto.owner = THIS_MODULE; 2453 vsock_device.minor = MISC_DYNAMIC_MINOR; 2454 err = misc_register(&vsock_device); 2455 if (err) { 2456 pr_err("Failed to register misc device\n"); 2457 goto err_reset_transport; 2458 } 2459 2460 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2461 if (err) { 2462 pr_err("Cannot register vsock protocol\n"); 2463 goto err_deregister_misc; 2464 } 2465 2466 err = sock_register(&vsock_family_ops); 2467 if (err) { 2468 pr_err("could not register af_vsock (%d) address family: %d\n", 2469 AF_VSOCK, err); 2470 goto err_unregister_proto; 2471 } 2472 2473 vsock_bpf_build_proto(); 2474 2475 return 0; 2476 2477 err_unregister_proto: 2478 proto_unregister(&vsock_proto); 2479 err_deregister_misc: 2480 misc_deregister(&vsock_device); 2481 err_reset_transport: 2482 return err; 2483 } 2484 2485 static void __exit vsock_exit(void) 2486 { 2487 misc_deregister(&vsock_device); 2488 sock_unregister(AF_VSOCK); 2489 proto_unregister(&vsock_proto); 2490 } 2491 2492 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2493 { 2494 return vsk->transport; 2495 } 2496 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2497 2498 int vsock_core_register(const struct vsock_transport *t, int features) 2499 { 2500 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2501 int err = mutex_lock_interruptible(&vsock_register_mutex); 2502 2503 if (err) 2504 return err; 2505 2506 t_h2g = transport_h2g; 2507 t_g2h = transport_g2h; 2508 t_dgram = transport_dgram; 2509 t_local = transport_local; 2510 2511 if (features & VSOCK_TRANSPORT_F_H2G) { 2512 if (t_h2g) { 2513 err = -EBUSY; 2514 goto err_busy; 2515 } 2516 t_h2g = t; 2517 } 2518 2519 if (features & VSOCK_TRANSPORT_F_G2H) { 2520 if (t_g2h) { 2521 err = -EBUSY; 2522 goto err_busy; 2523 } 2524 t_g2h = t; 2525 } 2526 2527 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2528 if (t_dgram) { 2529 err = -EBUSY; 2530 goto err_busy; 2531 } 2532 t_dgram = t; 2533 } 2534 2535 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2536 if (t_local) { 2537 err = -EBUSY; 2538 goto err_busy; 2539 } 2540 t_local = t; 2541 } 2542 2543 transport_h2g = t_h2g; 2544 transport_g2h = t_g2h; 2545 transport_dgram = t_dgram; 2546 transport_local = t_local; 2547 2548 err_busy: 2549 mutex_unlock(&vsock_register_mutex); 2550 return err; 2551 } 2552 EXPORT_SYMBOL_GPL(vsock_core_register); 2553 2554 void vsock_core_unregister(const struct vsock_transport *t) 2555 { 2556 mutex_lock(&vsock_register_mutex); 2557 2558 if (transport_h2g == t) 2559 transport_h2g = NULL; 2560 2561 if (transport_g2h == t) 2562 transport_g2h = NULL; 2563 2564 if (transport_dgram == t) 2565 transport_dgram = NULL; 2566 2567 if (transport_local == t) 2568 transport_local = NULL; 2569 2570 mutex_unlock(&vsock_register_mutex); 2571 } 2572 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2573 2574 module_init(vsock_init); 2575 module_exit(vsock_exit); 2576 2577 MODULE_AUTHOR("VMware, Inc."); 2578 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2579 MODULE_VERSION("1.0.2.0-k"); 2580 MODULE_LICENSE("GPL v2"); 2581