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 116static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr); 117static void vsock_sk_destruct(struct sock *sk); 118static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 119 120/* Protocol family. */ 121struct 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 */ 140static const struct vsock_transport *transport_h2g; 141/* Transport used for guest->host communication */ 142static const struct vsock_transport *transport_g2h; 143/* Transport used for DGRAM communication */ 144static const struct vsock_transport *transport_dgram; 145/* Transport used for local communication */ 146static const struct vsock_transport *transport_local; 147static 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 179struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 180EXPORT_SYMBOL_GPL(vsock_bind_table); 181struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 182EXPORT_SYMBOL_GPL(vsock_connected_table); 183DEFINE_SPINLOCK(vsock_table_lock); 184EXPORT_SYMBOL_GPL(vsock_table_lock); 185 186/* Autobind this socket to the local address if necessary. */ 187static 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 198static 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 209static 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 216static 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 223static void __vsock_remove_bound(struct vsock_sock *vsk) 224{ 225 list_del_init(&vsk->bound_table); 226 sock_put(&vsk->sk); 227} 228 229static void __vsock_remove_connected(struct vsock_sock *vsk) 230{ 231 list_del_init(&vsk->connected_table); 232 sock_put(&vsk->sk); 233} 234 235static 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 252static 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 268static 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 275void 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} 284EXPORT_SYMBOL_GPL(vsock_insert_connected); 285 286void 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} 293EXPORT_SYMBOL_GPL(vsock_remove_bound); 294 295void 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} 302EXPORT_SYMBOL_GPL(vsock_remove_connected); 303 304struct 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} 317EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 318 319struct 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} 333EXPORT_SYMBOL_GPL(vsock_find_connected_socket); 334 335void vsock_remove_sock(struct vsock_sock *vsk) 336{ 337 vsock_remove_bound(vsk); 338 vsock_remove_connected(vsk); 339} 340EXPORT_SYMBOL_GPL(vsock_remove_sock); 341 342void 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} 362EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket); 363 364void 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} 376EXPORT_SYMBOL_GPL(vsock_add_pending); 377 378void 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} 386EXPORT_SYMBOL_GPL(vsock_remove_pending); 387 388void 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} 400EXPORT_SYMBOL_GPL(vsock_enqueue_accept); 401 402static 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 417static 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 */ 439int 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} 517EXPORT_SYMBOL_GPL(vsock_assign_transport); 518 519bool 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} 532EXPORT_SYMBOL_GPL(vsock_find_cid); 533 534static 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 556static 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 562static 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 568static 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 578static 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 615out: 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 627static 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 682static int __vsock_bind_dgram(struct vsock_sock *vsk, 683 struct sockaddr_vm *addr) 684{ 685 return vsk->transport->dgram_bind(vsk, addr); 686} 687 688static 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 725static void vsock_connect_timeout(struct work_struct *work); 726 727static 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 792static bool sock_type_connectible(u16 type) 793{ 794 return (type == SOCK_STREAM) || (type == SOCK_SEQPACKET); 795} 796 797static 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 834static 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 849static 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 860struct 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} 865EXPORT_SYMBOL_GPL(vsock_create_connected); 866 867s64 vsock_stream_has_data(struct vsock_sock *vsk) 868{ 869 return vsk->transport->stream_has_data(vsk); 870} 871EXPORT_SYMBOL_GPL(vsock_stream_has_data); 872 873s64 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} 882EXPORT_SYMBOL_GPL(vsock_connectible_has_data); 883 884s64 vsock_stream_has_space(struct vsock_sock *vsk) 885{ 886 return vsk->transport->stream_has_space(vsk); 887} 888EXPORT_SYMBOL_GPL(vsock_stream_has_space); 889 890void 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} 898EXPORT_SYMBOL_GPL(vsock_data_ready); 899 900static 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 909static int 910vsock_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 928static 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 966out: 967 release_sock(sk); 968 return err; 969} 970 971static 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 1017out: 1018 release_sock(sk); 1019 return err; 1020} 1021 1022static __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 1140static 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 1147static 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 1216out: 1217 release_sock(sk); 1218 return err; 1219} 1220 1221static 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 1268out: 1269 release_sock(sk); 1270 return err; 1271} 1272 1273int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1274 size_t len, int flags) 1275{ 1276#ifdef CONFIG_BPF_SYSCALL 1277 const struct proto *prot; 1278#endif 1279 struct vsock_sock *vsk; 1280 struct sock *sk; 1281 1282 sk = sock->sk; 1283 vsk = vsock_sk(sk); 1284 1285#ifdef CONFIG_BPF_SYSCALL 1286 prot = READ_ONCE(sk->sk_prot); 1287 if (prot != &vsock_proto) 1288 return prot->recvmsg(sk, msg, len, flags, NULL); 1289#endif 1290 1291 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1292} 1293EXPORT_SYMBOL_GPL(vsock_dgram_recvmsg); 1294 1295static const struct proto_ops vsock_dgram_ops = { 1296 .family = PF_VSOCK, 1297 .owner = THIS_MODULE, 1298 .release = vsock_release, 1299 .bind = vsock_bind, 1300 .connect = vsock_dgram_connect, 1301 .socketpair = sock_no_socketpair, 1302 .accept = sock_no_accept, 1303 .getname = vsock_getname, 1304 .poll = vsock_poll, 1305 .ioctl = sock_no_ioctl, 1306 .listen = sock_no_listen, 1307 .shutdown = vsock_shutdown, 1308 .sendmsg = vsock_dgram_sendmsg, 1309 .recvmsg = vsock_dgram_recvmsg, 1310 .mmap = sock_no_mmap, 1311 .read_skb = vsock_read_skb, 1312}; 1313 1314static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1315{ 1316 const struct vsock_transport *transport = vsk->transport; 1317 1318 if (!transport || !transport->cancel_pkt) 1319 return -EOPNOTSUPP; 1320 1321 return transport->cancel_pkt(vsk); 1322} 1323 1324static void vsock_connect_timeout(struct work_struct *work) 1325{ 1326 struct sock *sk; 1327 struct vsock_sock *vsk; 1328 1329 vsk = container_of(work, struct vsock_sock, connect_work.work); 1330 sk = sk_vsock(vsk); 1331 1332 lock_sock(sk); 1333 if (sk->sk_state == TCP_SYN_SENT && 1334 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1335 sk->sk_state = TCP_CLOSE; 1336 sk->sk_socket->state = SS_UNCONNECTED; 1337 sk->sk_err = ETIMEDOUT; 1338 sk_error_report(sk); 1339 vsock_transport_cancel_pkt(vsk); 1340 } 1341 release_sock(sk); 1342 1343 sock_put(sk); 1344} 1345 1346static int vsock_connect(struct socket *sock, struct sockaddr *addr, 1347 int addr_len, int flags) 1348{ 1349 int err; 1350 struct sock *sk; 1351 struct vsock_sock *vsk; 1352 const struct vsock_transport *transport; 1353 struct sockaddr_vm *remote_addr; 1354 long timeout; 1355 DEFINE_WAIT(wait); 1356 1357 err = 0; 1358 sk = sock->sk; 1359 vsk = vsock_sk(sk); 1360 1361 lock_sock(sk); 1362 1363 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1364 switch (sock->state) { 1365 case SS_CONNECTED: 1366 err = -EISCONN; 1367 goto out; 1368 case SS_DISCONNECTING: 1369 err = -EINVAL; 1370 goto out; 1371 case SS_CONNECTING: 1372 /* This continues on so we can move sock into the SS_CONNECTED 1373 * state once the connection has completed (at which point err 1374 * will be set to zero also). Otherwise, we will either wait 1375 * for the connection or return -EALREADY should this be a 1376 * non-blocking call. 1377 */ 1378 err = -EALREADY; 1379 if (flags & O_NONBLOCK) 1380 goto out; 1381 break; 1382 default: 1383 if ((sk->sk_state == TCP_LISTEN) || 1384 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1385 err = -EINVAL; 1386 goto out; 1387 } 1388 1389 /* Set the remote address that we are connecting to. */ 1390 memcpy(&vsk->remote_addr, remote_addr, 1391 sizeof(vsk->remote_addr)); 1392 1393 err = vsock_assign_transport(vsk, NULL); 1394 if (err) 1395 goto out; 1396 1397 transport = vsk->transport; 1398 1399 /* The hypervisor and well-known contexts do not have socket 1400 * endpoints. 1401 */ 1402 if (!transport || 1403 !transport->stream_allow(remote_addr->svm_cid, 1404 remote_addr->svm_port)) { 1405 err = -ENETUNREACH; 1406 goto out; 1407 } 1408 1409 if (vsock_msgzerocopy_allow(transport)) { 1410 set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1411 } else if (sock_flag(sk, SOCK_ZEROCOPY)) { 1412 /* If this option was set before 'connect()', 1413 * when transport was unknown, check that this 1414 * feature is supported here. 1415 */ 1416 err = -EOPNOTSUPP; 1417 goto out; 1418 } 1419 1420 err = vsock_auto_bind(vsk); 1421 if (err) 1422 goto out; 1423 1424 sk->sk_state = TCP_SYN_SENT; 1425 1426 err = transport->connect(vsk); 1427 if (err < 0) 1428 goto out; 1429 1430 /* Mark sock as connecting and set the error code to in 1431 * progress in case this is a non-blocking connect. 1432 */ 1433 sock->state = SS_CONNECTING; 1434 err = -EINPROGRESS; 1435 } 1436 1437 /* The receive path will handle all communication until we are able to 1438 * enter the connected state. Here we wait for the connection to be 1439 * completed or a notification of an error. 1440 */ 1441 timeout = vsk->connect_timeout; 1442 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1443 1444 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1445 if (flags & O_NONBLOCK) { 1446 /* If we're not going to block, we schedule a timeout 1447 * function to generate a timeout on the connection 1448 * attempt, in case the peer doesn't respond in a 1449 * timely manner. We hold on to the socket until the 1450 * timeout fires. 1451 */ 1452 sock_hold(sk); 1453 1454 /* If the timeout function is already scheduled, 1455 * reschedule it, then ungrab the socket refcount to 1456 * keep it balanced. 1457 */ 1458 if (mod_delayed_work(system_wq, &vsk->connect_work, 1459 timeout)) 1460 sock_put(sk); 1461 1462 /* Skip ahead to preserve error code set above. */ 1463 goto out_wait; 1464 } 1465 1466 release_sock(sk); 1467 timeout = schedule_timeout(timeout); 1468 lock_sock(sk); 1469 1470 if (signal_pending(current)) { 1471 err = sock_intr_errno(timeout); 1472 sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; 1473 sock->state = SS_UNCONNECTED; 1474 vsock_transport_cancel_pkt(vsk); 1475 vsock_remove_connected(vsk); 1476 goto out_wait; 1477 } else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) { 1478 err = -ETIMEDOUT; 1479 sk->sk_state = TCP_CLOSE; 1480 sock->state = SS_UNCONNECTED; 1481 vsock_transport_cancel_pkt(vsk); 1482 goto out_wait; 1483 } 1484 1485 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1486 } 1487 1488 if (sk->sk_err) { 1489 err = -sk->sk_err; 1490 sk->sk_state = TCP_CLOSE; 1491 sock->state = SS_UNCONNECTED; 1492 } else { 1493 err = 0; 1494 } 1495 1496out_wait: 1497 finish_wait(sk_sleep(sk), &wait); 1498out: 1499 release_sock(sk); 1500 return err; 1501} 1502 1503static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1504 bool kern) 1505{ 1506 struct sock *listener; 1507 int err; 1508 struct sock *connected; 1509 struct vsock_sock *vconnected; 1510 long timeout; 1511 DEFINE_WAIT(wait); 1512 1513 err = 0; 1514 listener = sock->sk; 1515 1516 lock_sock(listener); 1517 1518 if (!sock_type_connectible(sock->type)) { 1519 err = -EOPNOTSUPP; 1520 goto out; 1521 } 1522 1523 if (listener->sk_state != TCP_LISTEN) { 1524 err = -EINVAL; 1525 goto out; 1526 } 1527 1528 /* Wait for children sockets to appear; these are the new sockets 1529 * created upon connection establishment. 1530 */ 1531 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1532 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1533 1534 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1535 listener->sk_err == 0) { 1536 release_sock(listener); 1537 timeout = schedule_timeout(timeout); 1538 finish_wait(sk_sleep(listener), &wait); 1539 lock_sock(listener); 1540 1541 if (signal_pending(current)) { 1542 err = sock_intr_errno(timeout); 1543 goto out; 1544 } else if (timeout == 0) { 1545 err = -EAGAIN; 1546 goto out; 1547 } 1548 1549 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1550 } 1551 finish_wait(sk_sleep(listener), &wait); 1552 1553 if (listener->sk_err) 1554 err = -listener->sk_err; 1555 1556 if (connected) { 1557 sk_acceptq_removed(listener); 1558 1559 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1560 vconnected = vsock_sk(connected); 1561 1562 /* If the listener socket has received an error, then we should 1563 * reject this socket and return. Note that we simply mark the 1564 * socket rejected, drop our reference, and let the cleanup 1565 * function handle the cleanup; the fact that we found it in 1566 * the listener's accept queue guarantees that the cleanup 1567 * function hasn't run yet. 1568 */ 1569 if (err) { 1570 vconnected->rejected = true; 1571 } else { 1572 newsock->state = SS_CONNECTED; 1573 sock_graft(connected, newsock); 1574 if (vsock_msgzerocopy_allow(vconnected->transport)) 1575 set_bit(SOCK_SUPPORT_ZC, 1576 &connected->sk_socket->flags); 1577 } 1578 1579 release_sock(connected); 1580 sock_put(connected); 1581 } 1582 1583out: 1584 release_sock(listener); 1585 return err; 1586} 1587 1588static int vsock_listen(struct socket *sock, int backlog) 1589{ 1590 int err; 1591 struct sock *sk; 1592 struct vsock_sock *vsk; 1593 1594 sk = sock->sk; 1595 1596 lock_sock(sk); 1597 1598 if (!sock_type_connectible(sk->sk_type)) { 1599 err = -EOPNOTSUPP; 1600 goto out; 1601 } 1602 1603 if (sock->state != SS_UNCONNECTED) { 1604 err = -EINVAL; 1605 goto out; 1606 } 1607 1608 vsk = vsock_sk(sk); 1609 1610 if (!vsock_addr_bound(&vsk->local_addr)) { 1611 err = -EINVAL; 1612 goto out; 1613 } 1614 1615 sk->sk_max_ack_backlog = backlog; 1616 sk->sk_state = TCP_LISTEN; 1617 1618 err = 0; 1619 1620out: 1621 release_sock(sk); 1622 return err; 1623} 1624 1625static void vsock_update_buffer_size(struct vsock_sock *vsk, 1626 const struct vsock_transport *transport, 1627 u64 val) 1628{ 1629 if (val > vsk->buffer_max_size) 1630 val = vsk->buffer_max_size; 1631 1632 if (val < vsk->buffer_min_size) 1633 val = vsk->buffer_min_size; 1634 1635 if (val != vsk->buffer_size && 1636 transport && transport->notify_buffer_size) 1637 transport->notify_buffer_size(vsk, &val); 1638 1639 vsk->buffer_size = val; 1640} 1641 1642static int vsock_connectible_setsockopt(struct socket *sock, 1643 int level, 1644 int optname, 1645 sockptr_t optval, 1646 unsigned int optlen) 1647{ 1648 int err; 1649 struct sock *sk; 1650 struct vsock_sock *vsk; 1651 const struct vsock_transport *transport; 1652 u64 val; 1653 1654 if (level != AF_VSOCK && level != SOL_SOCKET) 1655 return -ENOPROTOOPT; 1656 1657#define COPY_IN(_v) \ 1658 do { \ 1659 if (optlen < sizeof(_v)) { \ 1660 err = -EINVAL; \ 1661 goto exit; \ 1662 } \ 1663 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1664 err = -EFAULT; \ 1665 goto exit; \ 1666 } \ 1667 } while (0) 1668 1669 err = 0; 1670 sk = sock->sk; 1671 vsk = vsock_sk(sk); 1672 1673 lock_sock(sk); 1674 1675 transport = vsk->transport; 1676 1677 if (level == SOL_SOCKET) { 1678 int zerocopy; 1679 1680 if (optname != SO_ZEROCOPY) { 1681 release_sock(sk); 1682 return sock_setsockopt(sock, level, optname, optval, optlen); 1683 } 1684 1685 /* Use 'int' type here, because variable to 1686 * set this option usually has this type. 1687 */ 1688 COPY_IN(zerocopy); 1689 1690 if (zerocopy < 0 || zerocopy > 1) { 1691 err = -EINVAL; 1692 goto exit; 1693 } 1694 1695 if (transport && !vsock_msgzerocopy_allow(transport)) { 1696 err = -EOPNOTSUPP; 1697 goto exit; 1698 } 1699 1700 sock_valbool_flag(sk, SOCK_ZEROCOPY, zerocopy); 1701 goto exit; 1702 } 1703 1704 switch (optname) { 1705 case SO_VM_SOCKETS_BUFFER_SIZE: 1706 COPY_IN(val); 1707 vsock_update_buffer_size(vsk, transport, val); 1708 break; 1709 1710 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1711 COPY_IN(val); 1712 vsk->buffer_max_size = val; 1713 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1714 break; 1715 1716 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1717 COPY_IN(val); 1718 vsk->buffer_min_size = val; 1719 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1720 break; 1721 1722 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1723 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: { 1724 struct __kernel_sock_timeval tv; 1725 1726 err = sock_copy_user_timeval(&tv, optval, optlen, 1727 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1728 if (err) 1729 break; 1730 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1731 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1732 vsk->connect_timeout = tv.tv_sec * HZ + 1733 DIV_ROUND_UP((unsigned long)tv.tv_usec, (USEC_PER_SEC / HZ)); 1734 if (vsk->connect_timeout == 0) 1735 vsk->connect_timeout = 1736 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1737 1738 } else { 1739 err = -ERANGE; 1740 } 1741 break; 1742 } 1743 1744 default: 1745 err = -ENOPROTOOPT; 1746 break; 1747 } 1748 1749#undef COPY_IN 1750 1751exit: 1752 release_sock(sk); 1753 return err; 1754} 1755 1756static int vsock_connectible_getsockopt(struct socket *sock, 1757 int level, int optname, 1758 char __user *optval, 1759 int __user *optlen) 1760{ 1761 struct sock *sk = sock->sk; 1762 struct vsock_sock *vsk = vsock_sk(sk); 1763 1764 union { 1765 u64 val64; 1766 struct old_timeval32 tm32; 1767 struct __kernel_old_timeval tm; 1768 struct __kernel_sock_timeval stm; 1769 } v; 1770 1771 int lv = sizeof(v.val64); 1772 int len; 1773 1774 if (level != AF_VSOCK) 1775 return -ENOPROTOOPT; 1776 1777 if (get_user(len, optlen)) 1778 return -EFAULT; 1779 1780 memset(&v, 0, sizeof(v)); 1781 1782 switch (optname) { 1783 case SO_VM_SOCKETS_BUFFER_SIZE: 1784 v.val64 = vsk->buffer_size; 1785 break; 1786 1787 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1788 v.val64 = vsk->buffer_max_size; 1789 break; 1790 1791 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1792 v.val64 = vsk->buffer_min_size; 1793 break; 1794 1795 case SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW: 1796 case SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD: 1797 lv = sock_get_timeout(vsk->connect_timeout, &v, 1798 optname == SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD); 1799 break; 1800 1801 default: 1802 return -ENOPROTOOPT; 1803 } 1804 1805 if (len < lv) 1806 return -EINVAL; 1807 if (len > lv) 1808 len = lv; 1809 if (copy_to_user(optval, &v, len)) 1810 return -EFAULT; 1811 1812 if (put_user(len, optlen)) 1813 return -EFAULT; 1814 1815 return 0; 1816} 1817 1818static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, 1819 size_t len) 1820{ 1821 struct sock *sk; 1822 struct vsock_sock *vsk; 1823 const struct vsock_transport *transport; 1824 ssize_t total_written; 1825 long timeout; 1826 int err; 1827 struct vsock_transport_send_notify_data send_data; 1828 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1829 1830 sk = sock->sk; 1831 vsk = vsock_sk(sk); 1832 total_written = 0; 1833 err = 0; 1834 1835 if (msg->msg_flags & MSG_OOB) 1836 return -EOPNOTSUPP; 1837 1838 lock_sock(sk); 1839 1840 transport = vsk->transport; 1841 1842 /* Callers should not provide a destination with connection oriented 1843 * sockets. 1844 */ 1845 if (msg->msg_namelen) { 1846 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1847 goto out; 1848 } 1849 1850 /* Send data only if both sides are not shutdown in the direction. */ 1851 if (sk->sk_shutdown & SEND_SHUTDOWN || 1852 vsk->peer_shutdown & RCV_SHUTDOWN) { 1853 err = -EPIPE; 1854 goto out; 1855 } 1856 1857 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1858 !vsock_addr_bound(&vsk->local_addr)) { 1859 err = -ENOTCONN; 1860 goto out; 1861 } 1862 1863 if (!vsock_addr_bound(&vsk->remote_addr)) { 1864 err = -EDESTADDRREQ; 1865 goto out; 1866 } 1867 1868 if (msg->msg_flags & MSG_ZEROCOPY && 1869 !vsock_msgzerocopy_allow(transport)) { 1870 err = -EOPNOTSUPP; 1871 goto out; 1872 } 1873 1874 /* Wait for room in the produce queue to enqueue our user's data. */ 1875 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1876 1877 err = transport->notify_send_init(vsk, &send_data); 1878 if (err < 0) 1879 goto out; 1880 1881 while (total_written < len) { 1882 ssize_t written; 1883 1884 add_wait_queue(sk_sleep(sk), &wait); 1885 while (vsock_stream_has_space(vsk) == 0 && 1886 sk->sk_err == 0 && 1887 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1888 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1889 1890 /* Don't wait for non-blocking sockets. */ 1891 if (timeout == 0) { 1892 err = -EAGAIN; 1893 remove_wait_queue(sk_sleep(sk), &wait); 1894 goto out_err; 1895 } 1896 1897 err = transport->notify_send_pre_block(vsk, &send_data); 1898 if (err < 0) { 1899 remove_wait_queue(sk_sleep(sk), &wait); 1900 goto out_err; 1901 } 1902 1903 release_sock(sk); 1904 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1905 lock_sock(sk); 1906 if (signal_pending(current)) { 1907 err = sock_intr_errno(timeout); 1908 remove_wait_queue(sk_sleep(sk), &wait); 1909 goto out_err; 1910 } else if (timeout == 0) { 1911 err = -EAGAIN; 1912 remove_wait_queue(sk_sleep(sk), &wait); 1913 goto out_err; 1914 } 1915 } 1916 remove_wait_queue(sk_sleep(sk), &wait); 1917 1918 /* These checks occur both as part of and after the loop 1919 * conditional since we need to check before and after 1920 * sleeping. 1921 */ 1922 if (sk->sk_err) { 1923 err = -sk->sk_err; 1924 goto out_err; 1925 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1926 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1927 err = -EPIPE; 1928 goto out_err; 1929 } 1930 1931 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1932 if (err < 0) 1933 goto out_err; 1934 1935 /* Note that enqueue will only write as many bytes as are free 1936 * in the produce queue, so we don't need to ensure len is 1937 * smaller than the queue size. It is the caller's 1938 * responsibility to check how many bytes we were able to send. 1939 */ 1940 1941 if (sk->sk_type == SOCK_SEQPACKET) { 1942 written = transport->seqpacket_enqueue(vsk, 1943 msg, len - total_written); 1944 } else { 1945 written = transport->stream_enqueue(vsk, 1946 msg, len - total_written); 1947 } 1948 1949 if (written < 0) { 1950 err = written; 1951 goto out_err; 1952 } 1953 1954 total_written += written; 1955 1956 err = transport->notify_send_post_enqueue( 1957 vsk, written, &send_data); 1958 if (err < 0) 1959 goto out_err; 1960 1961 } 1962 1963out_err: 1964 if (total_written > 0) { 1965 /* Return number of written bytes only if: 1966 * 1) SOCK_STREAM socket. 1967 * 2) SOCK_SEQPACKET socket when whole buffer is sent. 1968 */ 1969 if (sk->sk_type == SOCK_STREAM || total_written == len) 1970 err = total_written; 1971 } 1972out: 1973 if (sk->sk_type == SOCK_STREAM) 1974 err = sk_stream_error(sk, msg->msg_flags, err); 1975 1976 release_sock(sk); 1977 return err; 1978} 1979 1980static int vsock_connectible_wait_data(struct sock *sk, 1981 struct wait_queue_entry *wait, 1982 long timeout, 1983 struct vsock_transport_recv_notify_data *recv_data, 1984 size_t target) 1985{ 1986 const struct vsock_transport *transport; 1987 struct vsock_sock *vsk; 1988 s64 data; 1989 int err; 1990 1991 vsk = vsock_sk(sk); 1992 err = 0; 1993 transport = vsk->transport; 1994 1995 while (1) { 1996 prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); 1997 data = vsock_connectible_has_data(vsk); 1998 if (data != 0) 1999 break; 2000 2001 if (sk->sk_err != 0 || 2002 (sk->sk_shutdown & RCV_SHUTDOWN) || 2003 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 2004 break; 2005 } 2006 2007 /* Don't wait for non-blocking sockets. */ 2008 if (timeout == 0) { 2009 err = -EAGAIN; 2010 break; 2011 } 2012 2013 if (recv_data) { 2014 err = transport->notify_recv_pre_block(vsk, target, recv_data); 2015 if (err < 0) 2016 break; 2017 } 2018 2019 release_sock(sk); 2020 timeout = schedule_timeout(timeout); 2021 lock_sock(sk); 2022 2023 if (signal_pending(current)) { 2024 err = sock_intr_errno(timeout); 2025 break; 2026 } else if (timeout == 0) { 2027 err = -EAGAIN; 2028 break; 2029 } 2030 } 2031 2032 finish_wait(sk_sleep(sk), wait); 2033 2034 if (err) 2035 return err; 2036 2037 /* Internal transport error when checking for available 2038 * data. XXX This should be changed to a connection 2039 * reset in a later change. 2040 */ 2041 if (data < 0) 2042 return -ENOMEM; 2043 2044 return data; 2045} 2046 2047static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, 2048 size_t len, int flags) 2049{ 2050 struct vsock_transport_recv_notify_data recv_data; 2051 const struct vsock_transport *transport; 2052 struct vsock_sock *vsk; 2053 ssize_t copied; 2054 size_t target; 2055 long timeout; 2056 int err; 2057 2058 DEFINE_WAIT(wait); 2059 2060 vsk = vsock_sk(sk); 2061 transport = vsk->transport; 2062 2063 /* We must not copy less than target bytes into the user's buffer 2064 * before returning successfully, so we wait for the consume queue to 2065 * have that much data to consume before dequeueing. Note that this 2066 * makes it impossible to handle cases where target is greater than the 2067 * queue size. 2068 */ 2069 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 2070 if (target >= transport->stream_rcvhiwat(vsk)) { 2071 err = -ENOMEM; 2072 goto out; 2073 } 2074 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2075 copied = 0; 2076 2077 err = transport->notify_recv_init(vsk, target, &recv_data); 2078 if (err < 0) 2079 goto out; 2080 2081 2082 while (1) { 2083 ssize_t read; 2084 2085 err = vsock_connectible_wait_data(sk, &wait, timeout, 2086 &recv_data, target); 2087 if (err <= 0) 2088 break; 2089 2090 err = transport->notify_recv_pre_dequeue(vsk, target, 2091 &recv_data); 2092 if (err < 0) 2093 break; 2094 2095 read = transport->stream_dequeue(vsk, msg, len - copied, flags); 2096 if (read < 0) { 2097 err = read; 2098 break; 2099 } 2100 2101 copied += read; 2102 2103 err = transport->notify_recv_post_dequeue(vsk, target, read, 2104 !(flags & MSG_PEEK), &recv_data); 2105 if (err < 0) 2106 goto out; 2107 2108 if (read >= target || flags & MSG_PEEK) 2109 break; 2110 2111 target -= read; 2112 } 2113 2114 if (sk->sk_err) 2115 err = -sk->sk_err; 2116 else if (sk->sk_shutdown & RCV_SHUTDOWN) 2117 err = 0; 2118 2119 if (copied > 0) 2120 err = copied; 2121 2122out: 2123 return err; 2124} 2125 2126static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, 2127 size_t len, int flags) 2128{ 2129 const struct vsock_transport *transport; 2130 struct vsock_sock *vsk; 2131 ssize_t msg_len; 2132 long timeout; 2133 int err = 0; 2134 DEFINE_WAIT(wait); 2135 2136 vsk = vsock_sk(sk); 2137 transport = vsk->transport; 2138 2139 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 2140 2141 err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0); 2142 if (err <= 0) 2143 goto out; 2144 2145 msg_len = transport->seqpacket_dequeue(vsk, msg, flags); 2146 2147 if (msg_len < 0) { 2148 err = msg_len; 2149 goto out; 2150 } 2151 2152 if (sk->sk_err) { 2153 err = -sk->sk_err; 2154 } else if (sk->sk_shutdown & RCV_SHUTDOWN) { 2155 err = 0; 2156 } else { 2157 /* User sets MSG_TRUNC, so return real length of 2158 * packet. 2159 */ 2160 if (flags & MSG_TRUNC) 2161 err = msg_len; 2162 else 2163 err = len - msg_data_left(msg); 2164 2165 /* Always set MSG_TRUNC if real length of packet is 2166 * bigger than user's buffer. 2167 */ 2168 if (msg_len > len) 2169 msg->msg_flags |= MSG_TRUNC; 2170 } 2171 2172out: 2173 return err; 2174} 2175 2176int 2177vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2178 int flags) 2179{ 2180 struct sock *sk; 2181 struct vsock_sock *vsk; 2182 const struct vsock_transport *transport; 2183#ifdef CONFIG_BPF_SYSCALL 2184 const struct proto *prot; 2185#endif 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#ifdef CONFIG_BPF_SYSCALL 2237 prot = READ_ONCE(sk->sk_prot); 2238 if (prot != &vsock_proto) { 2239 release_sock(sk); 2240 return prot->recvmsg(sk, msg, len, flags, NULL); 2241 } 2242#endif 2243 2244 if (sk->sk_type == SOCK_STREAM) 2245 err = __vsock_stream_recvmsg(sk, msg, len, flags); 2246 else 2247 err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); 2248 2249out: 2250 release_sock(sk); 2251 return err; 2252} 2253EXPORT_SYMBOL_GPL(vsock_connectible_recvmsg); 2254 2255static int vsock_set_rcvlowat(struct sock *sk, int val) 2256{ 2257 const struct vsock_transport *transport; 2258 struct vsock_sock *vsk; 2259 2260 vsk = vsock_sk(sk); 2261 2262 if (val > vsk->buffer_size) 2263 return -EINVAL; 2264 2265 transport = vsk->transport; 2266 2267 if (transport && transport->notify_set_rcvlowat) { 2268 int err; 2269 2270 err = transport->notify_set_rcvlowat(vsk, val); 2271 if (err) 2272 return err; 2273 } 2274 2275 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 2276 return 0; 2277} 2278 2279static const struct proto_ops vsock_stream_ops = { 2280 .family = PF_VSOCK, 2281 .owner = THIS_MODULE, 2282 .release = vsock_release, 2283 .bind = vsock_bind, 2284 .connect = vsock_connect, 2285 .socketpair = sock_no_socketpair, 2286 .accept = vsock_accept, 2287 .getname = vsock_getname, 2288 .poll = vsock_poll, 2289 .ioctl = sock_no_ioctl, 2290 .listen = vsock_listen, 2291 .shutdown = vsock_shutdown, 2292 .setsockopt = vsock_connectible_setsockopt, 2293 .getsockopt = vsock_connectible_getsockopt, 2294 .sendmsg = vsock_connectible_sendmsg, 2295 .recvmsg = vsock_connectible_recvmsg, 2296 .mmap = sock_no_mmap, 2297 .set_rcvlowat = vsock_set_rcvlowat, 2298 .read_skb = vsock_read_skb, 2299}; 2300 2301static const struct proto_ops vsock_seqpacket_ops = { 2302 .family = PF_VSOCK, 2303 .owner = THIS_MODULE, 2304 .release = vsock_release, 2305 .bind = vsock_bind, 2306 .connect = vsock_connect, 2307 .socketpair = sock_no_socketpair, 2308 .accept = vsock_accept, 2309 .getname = vsock_getname, 2310 .poll = vsock_poll, 2311 .ioctl = sock_no_ioctl, 2312 .listen = vsock_listen, 2313 .shutdown = vsock_shutdown, 2314 .setsockopt = vsock_connectible_setsockopt, 2315 .getsockopt = vsock_connectible_getsockopt, 2316 .sendmsg = vsock_connectible_sendmsg, 2317 .recvmsg = vsock_connectible_recvmsg, 2318 .mmap = sock_no_mmap, 2319 .read_skb = vsock_read_skb, 2320}; 2321 2322static int vsock_create(struct net *net, struct socket *sock, 2323 int protocol, int kern) 2324{ 2325 struct vsock_sock *vsk; 2326 struct sock *sk; 2327 int ret; 2328 2329 if (!sock) 2330 return -EINVAL; 2331 2332 if (protocol && protocol != PF_VSOCK) 2333 return -EPROTONOSUPPORT; 2334 2335 switch (sock->type) { 2336 case SOCK_DGRAM: 2337 sock->ops = &vsock_dgram_ops; 2338 break; 2339 case SOCK_STREAM: 2340 sock->ops = &vsock_stream_ops; 2341 break; 2342 case SOCK_SEQPACKET: 2343 sock->ops = &vsock_seqpacket_ops; 2344 break; 2345 default: 2346 return -ESOCKTNOSUPPORT; 2347 } 2348 2349 sock->state = SS_UNCONNECTED; 2350 2351 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2352 if (!sk) 2353 return -ENOMEM; 2354 2355 vsk = vsock_sk(sk); 2356 2357 if (sock->type == SOCK_DGRAM) { 2358 ret = vsock_assign_transport(vsk, NULL); 2359 if (ret < 0) { 2360 sock_put(sk); 2361 return ret; 2362 } 2363 } 2364 2365 /* SOCK_DGRAM doesn't have 'setsockopt' callback set in its 2366 * proto_ops, so there is no handler for custom logic. 2367 */ 2368 if (sock_type_connectible(sock->type)) 2369 set_bit(SOCK_CUSTOM_SOCKOPT, &sk->sk_socket->flags); 2370 2371 vsock_insert_unbound(vsk); 2372 2373 return 0; 2374} 2375 2376static const struct net_proto_family vsock_family_ops = { 2377 .family = AF_VSOCK, 2378 .create = vsock_create, 2379 .owner = THIS_MODULE, 2380}; 2381 2382static long vsock_dev_do_ioctl(struct file *filp, 2383 unsigned int cmd, void __user *ptr) 2384{ 2385 u32 __user *p = ptr; 2386 u32 cid = VMADDR_CID_ANY; 2387 int retval = 0; 2388 2389 switch (cmd) { 2390 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2391 /* To be compatible with the VMCI behavior, we prioritize the 2392 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2393 */ 2394 if (transport_g2h) 2395 cid = transport_g2h->get_local_cid(); 2396 else if (transport_h2g) 2397 cid = transport_h2g->get_local_cid(); 2398 2399 if (put_user(cid, p) != 0) 2400 retval = -EFAULT; 2401 break; 2402 2403 default: 2404 retval = -ENOIOCTLCMD; 2405 } 2406 2407 return retval; 2408} 2409 2410static long vsock_dev_ioctl(struct file *filp, 2411 unsigned int cmd, unsigned long arg) 2412{ 2413 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2414} 2415 2416#ifdef CONFIG_COMPAT 2417static long vsock_dev_compat_ioctl(struct file *filp, 2418 unsigned int cmd, unsigned long arg) 2419{ 2420 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2421} 2422#endif 2423 2424static const struct file_operations vsock_device_ops = { 2425 .owner = THIS_MODULE, 2426 .unlocked_ioctl = vsock_dev_ioctl, 2427#ifdef CONFIG_COMPAT 2428 .compat_ioctl = vsock_dev_compat_ioctl, 2429#endif 2430 .open = nonseekable_open, 2431}; 2432 2433static struct miscdevice vsock_device = { 2434 .name = "vsock", 2435 .fops = &vsock_device_ops, 2436}; 2437 2438static int __init vsock_init(void) 2439{ 2440 int err = 0; 2441 2442 vsock_init_tables(); 2443 2444 vsock_proto.owner = THIS_MODULE; 2445 vsock_device.minor = MISC_DYNAMIC_MINOR; 2446 err = misc_register(&vsock_device); 2447 if (err) { 2448 pr_err("Failed to register misc device\n"); 2449 goto err_reset_transport; 2450 } 2451 2452 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2453 if (err) { 2454 pr_err("Cannot register vsock protocol\n"); 2455 goto err_deregister_misc; 2456 } 2457 2458 err = sock_register(&vsock_family_ops); 2459 if (err) { 2460 pr_err("could not register af_vsock (%d) address family: %d\n", 2461 AF_VSOCK, err); 2462 goto err_unregister_proto; 2463 } 2464 2465 vsock_bpf_build_proto(); 2466 2467 return 0; 2468 2469err_unregister_proto: 2470 proto_unregister(&vsock_proto); 2471err_deregister_misc: 2472 misc_deregister(&vsock_device); 2473err_reset_transport: 2474 return err; 2475} 2476 2477static void __exit vsock_exit(void) 2478{ 2479 misc_deregister(&vsock_device); 2480 sock_unregister(AF_VSOCK); 2481 proto_unregister(&vsock_proto); 2482} 2483 2484const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2485{ 2486 return vsk->transport; 2487} 2488EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2489 2490int vsock_core_register(const struct vsock_transport *t, int features) 2491{ 2492 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2493 int err = mutex_lock_interruptible(&vsock_register_mutex); 2494 2495 if (err) 2496 return err; 2497 2498 t_h2g = transport_h2g; 2499 t_g2h = transport_g2h; 2500 t_dgram = transport_dgram; 2501 t_local = transport_local; 2502 2503 if (features & VSOCK_TRANSPORT_F_H2G) { 2504 if (t_h2g) { 2505 err = -EBUSY; 2506 goto err_busy; 2507 } 2508 t_h2g = t; 2509 } 2510 2511 if (features & VSOCK_TRANSPORT_F_G2H) { 2512 if (t_g2h) { 2513 err = -EBUSY; 2514 goto err_busy; 2515 } 2516 t_g2h = t; 2517 } 2518 2519 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2520 if (t_dgram) { 2521 err = -EBUSY; 2522 goto err_busy; 2523 } 2524 t_dgram = t; 2525 } 2526 2527 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2528 if (t_local) { 2529 err = -EBUSY; 2530 goto err_busy; 2531 } 2532 t_local = t; 2533 } 2534 2535 transport_h2g = t_h2g; 2536 transport_g2h = t_g2h; 2537 transport_dgram = t_dgram; 2538 transport_local = t_local; 2539 2540err_busy: 2541 mutex_unlock(&vsock_register_mutex); 2542 return err; 2543} 2544EXPORT_SYMBOL_GPL(vsock_core_register); 2545 2546void vsock_core_unregister(const struct vsock_transport *t) 2547{ 2548 mutex_lock(&vsock_register_mutex); 2549 2550 if (transport_h2g == t) 2551 transport_h2g = NULL; 2552 2553 if (transport_g2h == t) 2554 transport_g2h = NULL; 2555 2556 if (transport_dgram == t) 2557 transport_dgram = NULL; 2558 2559 if (transport_local == t) 2560 transport_local = NULL; 2561 2562 mutex_unlock(&vsock_register_mutex); 2563} 2564EXPORT_SYMBOL_GPL(vsock_core_unregister); 2565 2566module_init(vsock_init); 2567module_exit(vsock_exit); 2568 2569MODULE_AUTHOR("VMware, Inc."); 2570MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2571MODULE_VERSION("1.0.2.0-k"); 2572MODULE_LICENSE("GPL v2"); 2573