1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Generic socket support routines. Memory allocators, socket lock/release 8 * handler for protocols to use and generic option handler. 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Florian La Roche, <flla@stud.uni-sb.de> 13 * Alan Cox, <A.Cox@swansea.ac.uk> 14 * 15 * Fixes: 16 * Alan Cox : Numerous verify_area() problems 17 * Alan Cox : Connecting on a connecting socket 18 * now returns an error for tcp. 19 * Alan Cox : sock->protocol is set correctly. 20 * and is not sometimes left as 0. 21 * Alan Cox : connect handles icmp errors on a 22 * connect properly. Unfortunately there 23 * is a restart syscall nasty there. I 24 * can't match BSD without hacking the C 25 * library. Ideas urgently sought! 26 * Alan Cox : Disallow bind() to addresses that are 27 * not ours - especially broadcast ones!! 28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) 29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, 30 * instead they leave that for the DESTROY timer. 31 * Alan Cox : Clean up error flag in accept 32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer 33 * was buggy. Put a remove_sock() in the handler 34 * for memory when we hit 0. Also altered the timer 35 * code. The ACK stuff can wait and needs major 36 * TCP layer surgery. 37 * Alan Cox : Fixed TCP ack bug, removed remove sock 38 * and fixed timer/inet_bh race. 39 * Alan Cox : Added zapped flag for TCP 40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code 41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb 42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources 43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. 44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... 45 * Rick Sladkey : Relaxed UDP rules for matching packets. 46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support 47 * Pauline Middelink : identd support 48 * Alan Cox : Fixed connect() taking signals I think. 49 * Alan Cox : SO_LINGER supported 50 * Alan Cox : Error reporting fixes 51 * Anonymous : inet_create tidied up (sk->reuse setting) 52 * Alan Cox : inet sockets don't set sk->type! 53 * Alan Cox : Split socket option code 54 * Alan Cox : Callbacks 55 * Alan Cox : Nagle flag for Charles & Johannes stuff 56 * Alex : Removed restriction on inet fioctl 57 * Alan Cox : Splitting INET from NET core 58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() 59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code 60 * Alan Cox : Split IP from generic code 61 * Alan Cox : New kfree_skbmem() 62 * Alan Cox : Make SO_DEBUG superuser only. 63 * Alan Cox : Allow anyone to clear SO_DEBUG 64 * (compatibility fix) 65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. 66 * Alan Cox : Allocator for a socket is settable. 67 * Alan Cox : SO_ERROR includes soft errors. 68 * Alan Cox : Allow NULL arguments on some SO_ opts 69 * Alan Cox : Generic socket allocation to make hooks 70 * easier (suggested by Craig Metz). 71 * Michael Pall : SO_ERROR returns positive errno again 72 * Steve Whitehouse: Added default destructor to free 73 * protocol private data. 74 * Steve Whitehouse: Added various other default routines 75 * common to several socket families. 76 * Chris Evans : Call suser() check last on F_SETOWN 77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. 78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() 79 * Andi Kleen : Fix write_space callback 80 * Chris Evans : Security fixes - signedness again 81 * Arnaldo C. Melo : cleanups, use skb_queue_purge 82 * 83 * To Fix: 84 */ 85 86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 87 88 #include <asm/unaligned.h> 89 #include <linux/capability.h> 90 #include <linux/errno.h> 91 #include <linux/errqueue.h> 92 #include <linux/types.h> 93 #include <linux/socket.h> 94 #include <linux/in.h> 95 #include <linux/kernel.h> 96 #include <linux/module.h> 97 #include <linux/proc_fs.h> 98 #include <linux/seq_file.h> 99 #include <linux/sched.h> 100 #include <linux/sched/mm.h> 101 #include <linux/timer.h> 102 #include <linux/string.h> 103 #include <linux/sockios.h> 104 #include <linux/net.h> 105 #include <linux/mm.h> 106 #include <linux/slab.h> 107 #include <linux/interrupt.h> 108 #include <linux/poll.h> 109 #include <linux/tcp.h> 110 #include <linux/init.h> 111 #include <linux/highmem.h> 112 #include <linux/user_namespace.h> 113 #include <linux/static_key.h> 114 #include <linux/memcontrol.h> 115 #include <linux/prefetch.h> 116 #include <linux/compat.h> 117 118 #include <linux/uaccess.h> 119 120 #include <linux/netdevice.h> 121 #include <net/protocol.h> 122 #include <linux/skbuff.h> 123 #include <net/net_namespace.h> 124 #include <net/request_sock.h> 125 #include <net/sock.h> 126 #include <linux/net_tstamp.h> 127 #include <net/xfrm.h> 128 #include <linux/ipsec.h> 129 #include <net/cls_cgroup.h> 130 #include <net/netprio_cgroup.h> 131 #include <linux/sock_diag.h> 132 133 #include <linux/filter.h> 134 #include <net/sock_reuseport.h> 135 #include <net/bpf_sk_storage.h> 136 137 #include <trace/events/sock.h> 138 139 #include <net/tcp.h> 140 #include <net/busy_poll.h> 141 142 #include <linux/ethtool.h> 143 144 static DEFINE_MUTEX(proto_list_mutex); 145 static LIST_HEAD(proto_list); 146 147 static void sock_inuse_add(struct net *net, int val); 148 149 /** 150 * sk_ns_capable - General socket capability test 151 * @sk: Socket to use a capability on or through 152 * @user_ns: The user namespace of the capability to use 153 * @cap: The capability to use 154 * 155 * Test to see if the opener of the socket had when the socket was 156 * created and the current process has the capability @cap in the user 157 * namespace @user_ns. 158 */ 159 bool sk_ns_capable(const struct sock *sk, 160 struct user_namespace *user_ns, int cap) 161 { 162 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 163 ns_capable(user_ns, cap); 164 } 165 EXPORT_SYMBOL(sk_ns_capable); 166 167 /** 168 * sk_capable - Socket global capability test 169 * @sk: Socket to use a capability on or through 170 * @cap: The global capability to use 171 * 172 * Test to see if the opener of the socket had when the socket was 173 * created and the current process has the capability @cap in all user 174 * namespaces. 175 */ 176 bool sk_capable(const struct sock *sk, int cap) 177 { 178 return sk_ns_capable(sk, &init_user_ns, cap); 179 } 180 EXPORT_SYMBOL(sk_capable); 181 182 /** 183 * sk_net_capable - Network namespace socket capability test 184 * @sk: Socket to use a capability on or through 185 * @cap: The capability to use 186 * 187 * Test to see if the opener of the socket had when the socket was created 188 * and the current process has the capability @cap over the network namespace 189 * the socket is a member of. 190 */ 191 bool sk_net_capable(const struct sock *sk, int cap) 192 { 193 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 194 } 195 EXPORT_SYMBOL(sk_net_capable); 196 197 /* 198 * Each address family might have different locking rules, so we have 199 * one slock key per address family and separate keys for internal and 200 * userspace sockets. 201 */ 202 static struct lock_class_key af_family_keys[AF_MAX]; 203 static struct lock_class_key af_family_kern_keys[AF_MAX]; 204 static struct lock_class_key af_family_slock_keys[AF_MAX]; 205 static struct lock_class_key af_family_kern_slock_keys[AF_MAX]; 206 207 /* 208 * Make lock validator output more readable. (we pre-construct these 209 * strings build-time, so that runtime initialization of socket 210 * locks is fast): 211 */ 212 213 #define _sock_locks(x) \ 214 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \ 215 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \ 216 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \ 217 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \ 218 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \ 219 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \ 220 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \ 221 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \ 222 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \ 223 x "27" , x "28" , x "AF_CAN" , \ 224 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \ 225 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \ 226 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \ 227 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \ 228 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \ 229 x "AF_MCTP" , \ 230 x "AF_MAX" 231 232 static const char *const af_family_key_strings[AF_MAX+1] = { 233 _sock_locks("sk_lock-") 234 }; 235 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 236 _sock_locks("slock-") 237 }; 238 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 239 _sock_locks("clock-") 240 }; 241 242 static const char *const af_family_kern_key_strings[AF_MAX+1] = { 243 _sock_locks("k-sk_lock-") 244 }; 245 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = { 246 _sock_locks("k-slock-") 247 }; 248 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = { 249 _sock_locks("k-clock-") 250 }; 251 static const char *const af_family_rlock_key_strings[AF_MAX+1] = { 252 _sock_locks("rlock-") 253 }; 254 static const char *const af_family_wlock_key_strings[AF_MAX+1] = { 255 _sock_locks("wlock-") 256 }; 257 static const char *const af_family_elock_key_strings[AF_MAX+1] = { 258 _sock_locks("elock-") 259 }; 260 261 /* 262 * sk_callback_lock and sk queues locking rules are per-address-family, 263 * so split the lock classes by using a per-AF key: 264 */ 265 static struct lock_class_key af_callback_keys[AF_MAX]; 266 static struct lock_class_key af_rlock_keys[AF_MAX]; 267 static struct lock_class_key af_wlock_keys[AF_MAX]; 268 static struct lock_class_key af_elock_keys[AF_MAX]; 269 static struct lock_class_key af_kern_callback_keys[AF_MAX]; 270 271 /* Run time adjustable parameters. */ 272 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 273 EXPORT_SYMBOL(sysctl_wmem_max); 274 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 275 EXPORT_SYMBOL(sysctl_rmem_max); 276 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 277 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 278 279 /* Maximal space eaten by iovec or ancillary data plus some space */ 280 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 281 EXPORT_SYMBOL(sysctl_optmem_max); 282 283 int sysctl_tstamp_allow_data __read_mostly = 1; 284 285 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key); 286 EXPORT_SYMBOL_GPL(memalloc_socks_key); 287 288 /** 289 * sk_set_memalloc - sets %SOCK_MEMALLOC 290 * @sk: socket to set it on 291 * 292 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 293 * It's the responsibility of the admin to adjust min_free_kbytes 294 * to meet the requirements 295 */ 296 void sk_set_memalloc(struct sock *sk) 297 { 298 sock_set_flag(sk, SOCK_MEMALLOC); 299 sk->sk_allocation |= __GFP_MEMALLOC; 300 static_branch_inc(&memalloc_socks_key); 301 } 302 EXPORT_SYMBOL_GPL(sk_set_memalloc); 303 304 void sk_clear_memalloc(struct sock *sk) 305 { 306 sock_reset_flag(sk, SOCK_MEMALLOC); 307 sk->sk_allocation &= ~__GFP_MEMALLOC; 308 static_branch_dec(&memalloc_socks_key); 309 310 /* 311 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 312 * progress of swapping. SOCK_MEMALLOC may be cleared while 313 * it has rmem allocations due to the last swapfile being deactivated 314 * but there is a risk that the socket is unusable due to exceeding 315 * the rmem limits. Reclaim the reserves and obey rmem limits again. 316 */ 317 sk_mem_reclaim(sk); 318 } 319 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 320 321 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 322 { 323 int ret; 324 unsigned int noreclaim_flag; 325 326 /* these should have been dropped before queueing */ 327 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 328 329 noreclaim_flag = memalloc_noreclaim_save(); 330 ret = sk->sk_backlog_rcv(sk, skb); 331 memalloc_noreclaim_restore(noreclaim_flag); 332 333 return ret; 334 } 335 EXPORT_SYMBOL(__sk_backlog_rcv); 336 337 void sk_error_report(struct sock *sk) 338 { 339 sk->sk_error_report(sk); 340 341 switch (sk->sk_family) { 342 case AF_INET: 343 fallthrough; 344 case AF_INET6: 345 trace_inet_sk_error_report(sk); 346 break; 347 default: 348 break; 349 } 350 } 351 EXPORT_SYMBOL(sk_error_report); 352 353 int sock_get_timeout(long timeo, void *optval, bool old_timeval) 354 { 355 struct __kernel_sock_timeval tv; 356 357 if (timeo == MAX_SCHEDULE_TIMEOUT) { 358 tv.tv_sec = 0; 359 tv.tv_usec = 0; 360 } else { 361 tv.tv_sec = timeo / HZ; 362 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ; 363 } 364 365 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 366 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec }; 367 *(struct old_timeval32 *)optval = tv32; 368 return sizeof(tv32); 369 } 370 371 if (old_timeval) { 372 struct __kernel_old_timeval old_tv; 373 old_tv.tv_sec = tv.tv_sec; 374 old_tv.tv_usec = tv.tv_usec; 375 *(struct __kernel_old_timeval *)optval = old_tv; 376 return sizeof(old_tv); 377 } 378 379 *(struct __kernel_sock_timeval *)optval = tv; 380 return sizeof(tv); 381 } 382 EXPORT_SYMBOL(sock_get_timeout); 383 384 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 385 sockptr_t optval, int optlen, bool old_timeval) 386 { 387 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 388 struct old_timeval32 tv32; 389 390 if (optlen < sizeof(tv32)) 391 return -EINVAL; 392 393 if (copy_from_sockptr(&tv32, optval, sizeof(tv32))) 394 return -EFAULT; 395 tv->tv_sec = tv32.tv_sec; 396 tv->tv_usec = tv32.tv_usec; 397 } else if (old_timeval) { 398 struct __kernel_old_timeval old_tv; 399 400 if (optlen < sizeof(old_tv)) 401 return -EINVAL; 402 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv))) 403 return -EFAULT; 404 tv->tv_sec = old_tv.tv_sec; 405 tv->tv_usec = old_tv.tv_usec; 406 } else { 407 if (optlen < sizeof(*tv)) 408 return -EINVAL; 409 if (copy_from_sockptr(tv, optval, sizeof(*tv))) 410 return -EFAULT; 411 } 412 413 return 0; 414 } 415 EXPORT_SYMBOL(sock_copy_user_timeval); 416 417 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen, 418 bool old_timeval) 419 { 420 struct __kernel_sock_timeval tv; 421 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval); 422 423 if (err) 424 return err; 425 426 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 427 return -EDOM; 428 429 if (tv.tv_sec < 0) { 430 static int warned __read_mostly; 431 432 *timeo_p = 0; 433 if (warned < 10 && net_ratelimit()) { 434 warned++; 435 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 436 __func__, current->comm, task_pid_nr(current)); 437 } 438 return 0; 439 } 440 *timeo_p = MAX_SCHEDULE_TIMEOUT; 441 if (tv.tv_sec == 0 && tv.tv_usec == 0) 442 return 0; 443 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) 444 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ); 445 return 0; 446 } 447 448 static bool sock_needs_netstamp(const struct sock *sk) 449 { 450 switch (sk->sk_family) { 451 case AF_UNSPEC: 452 case AF_UNIX: 453 return false; 454 default: 455 return true; 456 } 457 } 458 459 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 460 { 461 if (sk->sk_flags & flags) { 462 sk->sk_flags &= ~flags; 463 if (sock_needs_netstamp(sk) && 464 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 465 net_disable_timestamp(); 466 } 467 } 468 469 470 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 471 { 472 unsigned long flags; 473 struct sk_buff_head *list = &sk->sk_receive_queue; 474 475 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 476 atomic_inc(&sk->sk_drops); 477 trace_sock_rcvqueue_full(sk, skb); 478 return -ENOMEM; 479 } 480 481 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 482 atomic_inc(&sk->sk_drops); 483 return -ENOBUFS; 484 } 485 486 skb->dev = NULL; 487 skb_set_owner_r(skb, sk); 488 489 /* we escape from rcu protected region, make sure we dont leak 490 * a norefcounted dst 491 */ 492 skb_dst_force(skb); 493 494 spin_lock_irqsave(&list->lock, flags); 495 sock_skb_set_dropcount(sk, skb); 496 __skb_queue_tail(list, skb); 497 spin_unlock_irqrestore(&list->lock, flags); 498 499 if (!sock_flag(sk, SOCK_DEAD)) 500 sk->sk_data_ready(sk); 501 return 0; 502 } 503 EXPORT_SYMBOL(__sock_queue_rcv_skb); 504 505 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 506 { 507 int err; 508 509 err = sk_filter(sk, skb); 510 if (err) 511 return err; 512 513 return __sock_queue_rcv_skb(sk, skb); 514 } 515 EXPORT_SYMBOL(sock_queue_rcv_skb); 516 517 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 518 const int nested, unsigned int trim_cap, bool refcounted) 519 { 520 int rc = NET_RX_SUCCESS; 521 522 if (sk_filter_trim_cap(sk, skb, trim_cap)) 523 goto discard_and_relse; 524 525 skb->dev = NULL; 526 527 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 528 atomic_inc(&sk->sk_drops); 529 goto discard_and_relse; 530 } 531 if (nested) 532 bh_lock_sock_nested(sk); 533 else 534 bh_lock_sock(sk); 535 if (!sock_owned_by_user(sk)) { 536 /* 537 * trylock + unlock semantics: 538 */ 539 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 540 541 rc = sk_backlog_rcv(sk, skb); 542 543 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 544 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) { 545 bh_unlock_sock(sk); 546 atomic_inc(&sk->sk_drops); 547 goto discard_and_relse; 548 } 549 550 bh_unlock_sock(sk); 551 out: 552 if (refcounted) 553 sock_put(sk); 554 return rc; 555 discard_and_relse: 556 kfree_skb(skb); 557 goto out; 558 } 559 EXPORT_SYMBOL(__sk_receive_skb); 560 561 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *, 562 u32)); 563 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *, 564 u32)); 565 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 566 { 567 struct dst_entry *dst = __sk_dst_get(sk); 568 569 if (dst && dst->obsolete && 570 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check, 571 dst, cookie) == NULL) { 572 sk_tx_queue_clear(sk); 573 sk->sk_dst_pending_confirm = 0; 574 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 575 dst_release(dst); 576 return NULL; 577 } 578 579 return dst; 580 } 581 EXPORT_SYMBOL(__sk_dst_check); 582 583 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 584 { 585 struct dst_entry *dst = sk_dst_get(sk); 586 587 if (dst && dst->obsolete && 588 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check, 589 dst, cookie) == NULL) { 590 sk_dst_reset(sk); 591 dst_release(dst); 592 return NULL; 593 } 594 595 return dst; 596 } 597 EXPORT_SYMBOL(sk_dst_check); 598 599 static int sock_bindtoindex_locked(struct sock *sk, int ifindex) 600 { 601 int ret = -ENOPROTOOPT; 602 #ifdef CONFIG_NETDEVICES 603 struct net *net = sock_net(sk); 604 605 /* Sorry... */ 606 ret = -EPERM; 607 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW)) 608 goto out; 609 610 ret = -EINVAL; 611 if (ifindex < 0) 612 goto out; 613 614 sk->sk_bound_dev_if = ifindex; 615 if (sk->sk_prot->rehash) 616 sk->sk_prot->rehash(sk); 617 sk_dst_reset(sk); 618 619 ret = 0; 620 621 out: 622 #endif 623 624 return ret; 625 } 626 627 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk) 628 { 629 int ret; 630 631 if (lock_sk) 632 lock_sock(sk); 633 ret = sock_bindtoindex_locked(sk, ifindex); 634 if (lock_sk) 635 release_sock(sk); 636 637 return ret; 638 } 639 EXPORT_SYMBOL(sock_bindtoindex); 640 641 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen) 642 { 643 int ret = -ENOPROTOOPT; 644 #ifdef CONFIG_NETDEVICES 645 struct net *net = sock_net(sk); 646 char devname[IFNAMSIZ]; 647 int index; 648 649 ret = -EINVAL; 650 if (optlen < 0) 651 goto out; 652 653 /* Bind this socket to a particular device like "eth0", 654 * as specified in the passed interface name. If the 655 * name is "" or the option length is zero the socket 656 * is not bound. 657 */ 658 if (optlen > IFNAMSIZ - 1) 659 optlen = IFNAMSIZ - 1; 660 memset(devname, 0, sizeof(devname)); 661 662 ret = -EFAULT; 663 if (copy_from_sockptr(devname, optval, optlen)) 664 goto out; 665 666 index = 0; 667 if (devname[0] != '\0') { 668 struct net_device *dev; 669 670 rcu_read_lock(); 671 dev = dev_get_by_name_rcu(net, devname); 672 if (dev) 673 index = dev->ifindex; 674 rcu_read_unlock(); 675 ret = -ENODEV; 676 if (!dev) 677 goto out; 678 } 679 680 return sock_bindtoindex(sk, index, true); 681 out: 682 #endif 683 684 return ret; 685 } 686 687 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 688 int __user *optlen, int len) 689 { 690 int ret = -ENOPROTOOPT; 691 #ifdef CONFIG_NETDEVICES 692 struct net *net = sock_net(sk); 693 char devname[IFNAMSIZ]; 694 695 if (sk->sk_bound_dev_if == 0) { 696 len = 0; 697 goto zero; 698 } 699 700 ret = -EINVAL; 701 if (len < IFNAMSIZ) 702 goto out; 703 704 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 705 if (ret) 706 goto out; 707 708 len = strlen(devname) + 1; 709 710 ret = -EFAULT; 711 if (copy_to_user(optval, devname, len)) 712 goto out; 713 714 zero: 715 ret = -EFAULT; 716 if (put_user(len, optlen)) 717 goto out; 718 719 ret = 0; 720 721 out: 722 #endif 723 724 return ret; 725 } 726 727 bool sk_mc_loop(struct sock *sk) 728 { 729 if (dev_recursion_level()) 730 return false; 731 if (!sk) 732 return true; 733 switch (sk->sk_family) { 734 case AF_INET: 735 return inet_sk(sk)->mc_loop; 736 #if IS_ENABLED(CONFIG_IPV6) 737 case AF_INET6: 738 return inet6_sk(sk)->mc_loop; 739 #endif 740 } 741 WARN_ON_ONCE(1); 742 return true; 743 } 744 EXPORT_SYMBOL(sk_mc_loop); 745 746 void sock_set_reuseaddr(struct sock *sk) 747 { 748 lock_sock(sk); 749 sk->sk_reuse = SK_CAN_REUSE; 750 release_sock(sk); 751 } 752 EXPORT_SYMBOL(sock_set_reuseaddr); 753 754 void sock_set_reuseport(struct sock *sk) 755 { 756 lock_sock(sk); 757 sk->sk_reuseport = true; 758 release_sock(sk); 759 } 760 EXPORT_SYMBOL(sock_set_reuseport); 761 762 void sock_no_linger(struct sock *sk) 763 { 764 lock_sock(sk); 765 sk->sk_lingertime = 0; 766 sock_set_flag(sk, SOCK_LINGER); 767 release_sock(sk); 768 } 769 EXPORT_SYMBOL(sock_no_linger); 770 771 void sock_set_priority(struct sock *sk, u32 priority) 772 { 773 lock_sock(sk); 774 sk->sk_priority = priority; 775 release_sock(sk); 776 } 777 EXPORT_SYMBOL(sock_set_priority); 778 779 void sock_set_sndtimeo(struct sock *sk, s64 secs) 780 { 781 lock_sock(sk); 782 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1) 783 sk->sk_sndtimeo = secs * HZ; 784 else 785 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 786 release_sock(sk); 787 } 788 EXPORT_SYMBOL(sock_set_sndtimeo); 789 790 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns) 791 { 792 if (val) { 793 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new); 794 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns); 795 sock_set_flag(sk, SOCK_RCVTSTAMP); 796 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 797 } else { 798 sock_reset_flag(sk, SOCK_RCVTSTAMP); 799 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 800 } 801 } 802 803 void sock_enable_timestamps(struct sock *sk) 804 { 805 lock_sock(sk); 806 __sock_set_timestamps(sk, true, false, true); 807 release_sock(sk); 808 } 809 EXPORT_SYMBOL(sock_enable_timestamps); 810 811 void sock_set_timestamp(struct sock *sk, int optname, bool valbool) 812 { 813 switch (optname) { 814 case SO_TIMESTAMP_OLD: 815 __sock_set_timestamps(sk, valbool, false, false); 816 break; 817 case SO_TIMESTAMP_NEW: 818 __sock_set_timestamps(sk, valbool, true, false); 819 break; 820 case SO_TIMESTAMPNS_OLD: 821 __sock_set_timestamps(sk, valbool, false, true); 822 break; 823 case SO_TIMESTAMPNS_NEW: 824 __sock_set_timestamps(sk, valbool, true, true); 825 break; 826 } 827 } 828 829 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index) 830 { 831 struct net *net = sock_net(sk); 832 struct net_device *dev = NULL; 833 bool match = false; 834 int *vclock_index; 835 int i, num; 836 837 if (sk->sk_bound_dev_if) 838 dev = dev_get_by_index(net, sk->sk_bound_dev_if); 839 840 if (!dev) { 841 pr_err("%s: sock not bind to device\n", __func__); 842 return -EOPNOTSUPP; 843 } 844 845 num = ethtool_get_phc_vclocks(dev, &vclock_index); 846 for (i = 0; i < num; i++) { 847 if (*(vclock_index + i) == phc_index) { 848 match = true; 849 break; 850 } 851 } 852 853 if (num > 0) 854 kfree(vclock_index); 855 856 if (!match) 857 return -EINVAL; 858 859 sk->sk_bind_phc = phc_index; 860 861 return 0; 862 } 863 864 int sock_set_timestamping(struct sock *sk, int optname, 865 struct so_timestamping timestamping) 866 { 867 int val = timestamping.flags; 868 int ret; 869 870 if (val & ~SOF_TIMESTAMPING_MASK) 871 return -EINVAL; 872 873 if (val & SOF_TIMESTAMPING_OPT_ID && 874 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 875 if (sk->sk_protocol == IPPROTO_TCP && 876 sk->sk_type == SOCK_STREAM) { 877 if ((1 << sk->sk_state) & 878 (TCPF_CLOSE | TCPF_LISTEN)) 879 return -EINVAL; 880 sk->sk_tskey = tcp_sk(sk)->snd_una; 881 } else { 882 sk->sk_tskey = 0; 883 } 884 } 885 886 if (val & SOF_TIMESTAMPING_OPT_STATS && 887 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) 888 return -EINVAL; 889 890 if (val & SOF_TIMESTAMPING_BIND_PHC) { 891 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc); 892 if (ret) 893 return ret; 894 } 895 896 sk->sk_tsflags = val; 897 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW); 898 899 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 900 sock_enable_timestamp(sk, 901 SOCK_TIMESTAMPING_RX_SOFTWARE); 902 else 903 sock_disable_timestamp(sk, 904 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 905 return 0; 906 } 907 908 void sock_set_keepalive(struct sock *sk) 909 { 910 lock_sock(sk); 911 if (sk->sk_prot->keepalive) 912 sk->sk_prot->keepalive(sk, true); 913 sock_valbool_flag(sk, SOCK_KEEPOPEN, true); 914 release_sock(sk); 915 } 916 EXPORT_SYMBOL(sock_set_keepalive); 917 918 static void __sock_set_rcvbuf(struct sock *sk, int val) 919 { 920 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it 921 * as a negative value. 922 */ 923 val = min_t(int, val, INT_MAX / 2); 924 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 925 926 /* We double it on the way in to account for "struct sk_buff" etc. 927 * overhead. Applications assume that the SO_RCVBUF setting they make 928 * will allow that much actual data to be received on that socket. 929 * 930 * Applications are unaware that "struct sk_buff" and other overheads 931 * allocate from the receive buffer during socket buffer allocation. 932 * 933 * And after considering the possible alternatives, returning the value 934 * we actually used in getsockopt is the most desirable behavior. 935 */ 936 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF)); 937 } 938 939 void sock_set_rcvbuf(struct sock *sk, int val) 940 { 941 lock_sock(sk); 942 __sock_set_rcvbuf(sk, val); 943 release_sock(sk); 944 } 945 EXPORT_SYMBOL(sock_set_rcvbuf); 946 947 static void __sock_set_mark(struct sock *sk, u32 val) 948 { 949 if (val != sk->sk_mark) { 950 sk->sk_mark = val; 951 sk_dst_reset(sk); 952 } 953 } 954 955 void sock_set_mark(struct sock *sk, u32 val) 956 { 957 lock_sock(sk); 958 __sock_set_mark(sk, val); 959 release_sock(sk); 960 } 961 EXPORT_SYMBOL(sock_set_mark); 962 963 static void sock_release_reserved_memory(struct sock *sk, int bytes) 964 { 965 /* Round down bytes to multiple of pages */ 966 bytes &= ~(SK_MEM_QUANTUM - 1); 967 968 WARN_ON(bytes > sk->sk_reserved_mem); 969 sk->sk_reserved_mem -= bytes; 970 sk_mem_reclaim(sk); 971 } 972 973 static int sock_reserve_memory(struct sock *sk, int bytes) 974 { 975 long allocated; 976 bool charged; 977 int pages; 978 979 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk)) 980 return -EOPNOTSUPP; 981 982 if (!bytes) 983 return 0; 984 985 pages = sk_mem_pages(bytes); 986 987 /* pre-charge to memcg */ 988 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages, 989 GFP_KERNEL | __GFP_RETRY_MAYFAIL); 990 if (!charged) 991 return -ENOMEM; 992 993 /* pre-charge to forward_alloc */ 994 allocated = sk_memory_allocated_add(sk, pages); 995 /* If the system goes into memory pressure with this 996 * precharge, give up and return error. 997 */ 998 if (allocated > sk_prot_mem_limits(sk, 1)) { 999 sk_memory_allocated_sub(sk, pages); 1000 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages); 1001 return -ENOMEM; 1002 } 1003 sk->sk_forward_alloc += pages << SK_MEM_QUANTUM_SHIFT; 1004 1005 sk->sk_reserved_mem += pages << SK_MEM_QUANTUM_SHIFT; 1006 1007 return 0; 1008 } 1009 1010 /* 1011 * This is meant for all protocols to use and covers goings on 1012 * at the socket level. Everything here is generic. 1013 */ 1014 1015 int sock_setsockopt(struct socket *sock, int level, int optname, 1016 sockptr_t optval, unsigned int optlen) 1017 { 1018 struct so_timestamping timestamping; 1019 struct sock_txtime sk_txtime; 1020 struct sock *sk = sock->sk; 1021 int val; 1022 int valbool; 1023 struct linger ling; 1024 int ret = 0; 1025 1026 /* 1027 * Options without arguments 1028 */ 1029 1030 if (optname == SO_BINDTODEVICE) 1031 return sock_setbindtodevice(sk, optval, optlen); 1032 1033 if (optlen < sizeof(int)) 1034 return -EINVAL; 1035 1036 if (copy_from_sockptr(&val, optval, sizeof(val))) 1037 return -EFAULT; 1038 1039 valbool = val ? 1 : 0; 1040 1041 lock_sock(sk); 1042 1043 switch (optname) { 1044 case SO_DEBUG: 1045 if (val && !capable(CAP_NET_ADMIN)) 1046 ret = -EACCES; 1047 else 1048 sock_valbool_flag(sk, SOCK_DBG, valbool); 1049 break; 1050 case SO_REUSEADDR: 1051 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 1052 break; 1053 case SO_REUSEPORT: 1054 sk->sk_reuseport = valbool; 1055 break; 1056 case SO_TYPE: 1057 case SO_PROTOCOL: 1058 case SO_DOMAIN: 1059 case SO_ERROR: 1060 ret = -ENOPROTOOPT; 1061 break; 1062 case SO_DONTROUTE: 1063 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 1064 sk_dst_reset(sk); 1065 break; 1066 case SO_BROADCAST: 1067 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 1068 break; 1069 case SO_SNDBUF: 1070 /* Don't error on this BSD doesn't and if you think 1071 * about it this is right. Otherwise apps have to 1072 * play 'guess the biggest size' games. RCVBUF/SNDBUF 1073 * are treated in BSD as hints 1074 */ 1075 val = min_t(u32, val, sysctl_wmem_max); 1076 set_sndbuf: 1077 /* Ensure val * 2 fits into an int, to prevent max_t() 1078 * from treating it as a negative value. 1079 */ 1080 val = min_t(int, val, INT_MAX / 2); 1081 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 1082 WRITE_ONCE(sk->sk_sndbuf, 1083 max_t(int, val * 2, SOCK_MIN_SNDBUF)); 1084 /* Wake up sending tasks if we upped the value. */ 1085 sk->sk_write_space(sk); 1086 break; 1087 1088 case SO_SNDBUFFORCE: 1089 if (!capable(CAP_NET_ADMIN)) { 1090 ret = -EPERM; 1091 break; 1092 } 1093 1094 /* No negative values (to prevent underflow, as val will be 1095 * multiplied by 2). 1096 */ 1097 if (val < 0) 1098 val = 0; 1099 goto set_sndbuf; 1100 1101 case SO_RCVBUF: 1102 /* Don't error on this BSD doesn't and if you think 1103 * about it this is right. Otherwise apps have to 1104 * play 'guess the biggest size' games. RCVBUF/SNDBUF 1105 * are treated in BSD as hints 1106 */ 1107 __sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max)); 1108 break; 1109 1110 case SO_RCVBUFFORCE: 1111 if (!capable(CAP_NET_ADMIN)) { 1112 ret = -EPERM; 1113 break; 1114 } 1115 1116 /* No negative values (to prevent underflow, as val will be 1117 * multiplied by 2). 1118 */ 1119 __sock_set_rcvbuf(sk, max(val, 0)); 1120 break; 1121 1122 case SO_KEEPALIVE: 1123 if (sk->sk_prot->keepalive) 1124 sk->sk_prot->keepalive(sk, valbool); 1125 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 1126 break; 1127 1128 case SO_OOBINLINE: 1129 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 1130 break; 1131 1132 case SO_NO_CHECK: 1133 sk->sk_no_check_tx = valbool; 1134 break; 1135 1136 case SO_PRIORITY: 1137 if ((val >= 0 && val <= 6) || 1138 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 1139 sk->sk_priority = val; 1140 else 1141 ret = -EPERM; 1142 break; 1143 1144 case SO_LINGER: 1145 if (optlen < sizeof(ling)) { 1146 ret = -EINVAL; /* 1003.1g */ 1147 break; 1148 } 1149 if (copy_from_sockptr(&ling, optval, sizeof(ling))) { 1150 ret = -EFAULT; 1151 break; 1152 } 1153 if (!ling.l_onoff) 1154 sock_reset_flag(sk, SOCK_LINGER); 1155 else { 1156 #if (BITS_PER_LONG == 32) 1157 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 1158 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 1159 else 1160 #endif 1161 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 1162 sock_set_flag(sk, SOCK_LINGER); 1163 } 1164 break; 1165 1166 case SO_BSDCOMPAT: 1167 break; 1168 1169 case SO_PASSCRED: 1170 if (valbool) 1171 set_bit(SOCK_PASSCRED, &sock->flags); 1172 else 1173 clear_bit(SOCK_PASSCRED, &sock->flags); 1174 break; 1175 1176 case SO_TIMESTAMP_OLD: 1177 case SO_TIMESTAMP_NEW: 1178 case SO_TIMESTAMPNS_OLD: 1179 case SO_TIMESTAMPNS_NEW: 1180 sock_set_timestamp(sk, optname, valbool); 1181 break; 1182 1183 case SO_TIMESTAMPING_NEW: 1184 case SO_TIMESTAMPING_OLD: 1185 if (optlen == sizeof(timestamping)) { 1186 if (copy_from_sockptr(×tamping, optval, 1187 sizeof(timestamping))) { 1188 ret = -EFAULT; 1189 break; 1190 } 1191 } else { 1192 memset(×tamping, 0, sizeof(timestamping)); 1193 timestamping.flags = val; 1194 } 1195 ret = sock_set_timestamping(sk, optname, timestamping); 1196 break; 1197 1198 case SO_RCVLOWAT: 1199 if (val < 0) 1200 val = INT_MAX; 1201 if (sock->ops->set_rcvlowat) 1202 ret = sock->ops->set_rcvlowat(sk, val); 1203 else 1204 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 1205 break; 1206 1207 case SO_RCVTIMEO_OLD: 1208 case SO_RCVTIMEO_NEW: 1209 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, 1210 optlen, optname == SO_RCVTIMEO_OLD); 1211 break; 1212 1213 case SO_SNDTIMEO_OLD: 1214 case SO_SNDTIMEO_NEW: 1215 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, 1216 optlen, optname == SO_SNDTIMEO_OLD); 1217 break; 1218 1219 case SO_ATTACH_FILTER: { 1220 struct sock_fprog fprog; 1221 1222 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); 1223 if (!ret) 1224 ret = sk_attach_filter(&fprog, sk); 1225 break; 1226 } 1227 case SO_ATTACH_BPF: 1228 ret = -EINVAL; 1229 if (optlen == sizeof(u32)) { 1230 u32 ufd; 1231 1232 ret = -EFAULT; 1233 if (copy_from_sockptr(&ufd, optval, sizeof(ufd))) 1234 break; 1235 1236 ret = sk_attach_bpf(ufd, sk); 1237 } 1238 break; 1239 1240 case SO_ATTACH_REUSEPORT_CBPF: { 1241 struct sock_fprog fprog; 1242 1243 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); 1244 if (!ret) 1245 ret = sk_reuseport_attach_filter(&fprog, sk); 1246 break; 1247 } 1248 case SO_ATTACH_REUSEPORT_EBPF: 1249 ret = -EINVAL; 1250 if (optlen == sizeof(u32)) { 1251 u32 ufd; 1252 1253 ret = -EFAULT; 1254 if (copy_from_sockptr(&ufd, optval, sizeof(ufd))) 1255 break; 1256 1257 ret = sk_reuseport_attach_bpf(ufd, sk); 1258 } 1259 break; 1260 1261 case SO_DETACH_REUSEPORT_BPF: 1262 ret = reuseport_detach_prog(sk); 1263 break; 1264 1265 case SO_DETACH_FILTER: 1266 ret = sk_detach_filter(sk); 1267 break; 1268 1269 case SO_LOCK_FILTER: 1270 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 1271 ret = -EPERM; 1272 else 1273 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 1274 break; 1275 1276 case SO_PASSSEC: 1277 if (valbool) 1278 set_bit(SOCK_PASSSEC, &sock->flags); 1279 else 1280 clear_bit(SOCK_PASSSEC, &sock->flags); 1281 break; 1282 case SO_MARK: 1283 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1284 ret = -EPERM; 1285 break; 1286 } 1287 1288 __sock_set_mark(sk, val); 1289 break; 1290 1291 case SO_RXQ_OVFL: 1292 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 1293 break; 1294 1295 case SO_WIFI_STATUS: 1296 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 1297 break; 1298 1299 case SO_PEEK_OFF: 1300 if (sock->ops->set_peek_off) 1301 ret = sock->ops->set_peek_off(sk, val); 1302 else 1303 ret = -EOPNOTSUPP; 1304 break; 1305 1306 case SO_NOFCS: 1307 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 1308 break; 1309 1310 case SO_SELECT_ERR_QUEUE: 1311 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 1312 break; 1313 1314 #ifdef CONFIG_NET_RX_BUSY_POLL 1315 case SO_BUSY_POLL: 1316 /* allow unprivileged users to decrease the value */ 1317 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 1318 ret = -EPERM; 1319 else { 1320 if (val < 0) 1321 ret = -EINVAL; 1322 else 1323 WRITE_ONCE(sk->sk_ll_usec, val); 1324 } 1325 break; 1326 case SO_PREFER_BUSY_POLL: 1327 if (valbool && !capable(CAP_NET_ADMIN)) 1328 ret = -EPERM; 1329 else 1330 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool); 1331 break; 1332 case SO_BUSY_POLL_BUDGET: 1333 if (val > READ_ONCE(sk->sk_busy_poll_budget) && !capable(CAP_NET_ADMIN)) { 1334 ret = -EPERM; 1335 } else { 1336 if (val < 0 || val > U16_MAX) 1337 ret = -EINVAL; 1338 else 1339 WRITE_ONCE(sk->sk_busy_poll_budget, val); 1340 } 1341 break; 1342 #endif 1343 1344 case SO_MAX_PACING_RATE: 1345 { 1346 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val; 1347 1348 if (sizeof(ulval) != sizeof(val) && 1349 optlen >= sizeof(ulval) && 1350 copy_from_sockptr(&ulval, optval, sizeof(ulval))) { 1351 ret = -EFAULT; 1352 break; 1353 } 1354 if (ulval != ~0UL) 1355 cmpxchg(&sk->sk_pacing_status, 1356 SK_PACING_NONE, 1357 SK_PACING_NEEDED); 1358 sk->sk_max_pacing_rate = ulval; 1359 sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval); 1360 break; 1361 } 1362 case SO_INCOMING_CPU: 1363 WRITE_ONCE(sk->sk_incoming_cpu, val); 1364 break; 1365 1366 case SO_CNX_ADVICE: 1367 if (val == 1) 1368 dst_negative_advice(sk); 1369 break; 1370 1371 case SO_ZEROCOPY: 1372 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) { 1373 if (!((sk->sk_type == SOCK_STREAM && 1374 sk->sk_protocol == IPPROTO_TCP) || 1375 (sk->sk_type == SOCK_DGRAM && 1376 sk->sk_protocol == IPPROTO_UDP))) 1377 ret = -ENOTSUPP; 1378 } else if (sk->sk_family != PF_RDS) { 1379 ret = -ENOTSUPP; 1380 } 1381 if (!ret) { 1382 if (val < 0 || val > 1) 1383 ret = -EINVAL; 1384 else 1385 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); 1386 } 1387 break; 1388 1389 case SO_TXTIME: 1390 if (optlen != sizeof(struct sock_txtime)) { 1391 ret = -EINVAL; 1392 break; 1393 } else if (copy_from_sockptr(&sk_txtime, optval, 1394 sizeof(struct sock_txtime))) { 1395 ret = -EFAULT; 1396 break; 1397 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) { 1398 ret = -EINVAL; 1399 break; 1400 } 1401 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet 1402 * scheduler has enough safe guards. 1403 */ 1404 if (sk_txtime.clockid != CLOCK_MONOTONIC && 1405 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1406 ret = -EPERM; 1407 break; 1408 } 1409 sock_valbool_flag(sk, SOCK_TXTIME, true); 1410 sk->sk_clockid = sk_txtime.clockid; 1411 sk->sk_txtime_deadline_mode = 1412 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE); 1413 sk->sk_txtime_report_errors = 1414 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS); 1415 break; 1416 1417 case SO_BINDTOIFINDEX: 1418 ret = sock_bindtoindex_locked(sk, val); 1419 break; 1420 1421 case SO_BUF_LOCK: 1422 if (val & ~SOCK_BUF_LOCK_MASK) { 1423 ret = -EINVAL; 1424 break; 1425 } 1426 sk->sk_userlocks = val | (sk->sk_userlocks & 1427 ~SOCK_BUF_LOCK_MASK); 1428 break; 1429 1430 case SO_RESERVE_MEM: 1431 { 1432 int delta; 1433 1434 if (val < 0) { 1435 ret = -EINVAL; 1436 break; 1437 } 1438 1439 delta = val - sk->sk_reserved_mem; 1440 if (delta < 0) 1441 sock_release_reserved_memory(sk, -delta); 1442 else 1443 ret = sock_reserve_memory(sk, delta); 1444 break; 1445 } 1446 1447 default: 1448 ret = -ENOPROTOOPT; 1449 break; 1450 } 1451 release_sock(sk); 1452 return ret; 1453 } 1454 EXPORT_SYMBOL(sock_setsockopt); 1455 1456 static const struct cred *sk_get_peer_cred(struct sock *sk) 1457 { 1458 const struct cred *cred; 1459 1460 spin_lock(&sk->sk_peer_lock); 1461 cred = get_cred(sk->sk_peer_cred); 1462 spin_unlock(&sk->sk_peer_lock); 1463 1464 return cred; 1465 } 1466 1467 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1468 struct ucred *ucred) 1469 { 1470 ucred->pid = pid_vnr(pid); 1471 ucred->uid = ucred->gid = -1; 1472 if (cred) { 1473 struct user_namespace *current_ns = current_user_ns(); 1474 1475 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1476 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1477 } 1478 } 1479 1480 static int groups_to_user(gid_t __user *dst, const struct group_info *src) 1481 { 1482 struct user_namespace *user_ns = current_user_ns(); 1483 int i; 1484 1485 for (i = 0; i < src->ngroups; i++) 1486 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i)) 1487 return -EFAULT; 1488 1489 return 0; 1490 } 1491 1492 int sock_getsockopt(struct socket *sock, int level, int optname, 1493 char __user *optval, int __user *optlen) 1494 { 1495 struct sock *sk = sock->sk; 1496 1497 union { 1498 int val; 1499 u64 val64; 1500 unsigned long ulval; 1501 struct linger ling; 1502 struct old_timeval32 tm32; 1503 struct __kernel_old_timeval tm; 1504 struct __kernel_sock_timeval stm; 1505 struct sock_txtime txtime; 1506 struct so_timestamping timestamping; 1507 } v; 1508 1509 int lv = sizeof(int); 1510 int len; 1511 1512 if (get_user(len, optlen)) 1513 return -EFAULT; 1514 if (len < 0) 1515 return -EINVAL; 1516 1517 memset(&v, 0, sizeof(v)); 1518 1519 switch (optname) { 1520 case SO_DEBUG: 1521 v.val = sock_flag(sk, SOCK_DBG); 1522 break; 1523 1524 case SO_DONTROUTE: 1525 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1526 break; 1527 1528 case SO_BROADCAST: 1529 v.val = sock_flag(sk, SOCK_BROADCAST); 1530 break; 1531 1532 case SO_SNDBUF: 1533 v.val = sk->sk_sndbuf; 1534 break; 1535 1536 case SO_RCVBUF: 1537 v.val = sk->sk_rcvbuf; 1538 break; 1539 1540 case SO_REUSEADDR: 1541 v.val = sk->sk_reuse; 1542 break; 1543 1544 case SO_REUSEPORT: 1545 v.val = sk->sk_reuseport; 1546 break; 1547 1548 case SO_KEEPALIVE: 1549 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1550 break; 1551 1552 case SO_TYPE: 1553 v.val = sk->sk_type; 1554 break; 1555 1556 case SO_PROTOCOL: 1557 v.val = sk->sk_protocol; 1558 break; 1559 1560 case SO_DOMAIN: 1561 v.val = sk->sk_family; 1562 break; 1563 1564 case SO_ERROR: 1565 v.val = -sock_error(sk); 1566 if (v.val == 0) 1567 v.val = xchg(&sk->sk_err_soft, 0); 1568 break; 1569 1570 case SO_OOBINLINE: 1571 v.val = sock_flag(sk, SOCK_URGINLINE); 1572 break; 1573 1574 case SO_NO_CHECK: 1575 v.val = sk->sk_no_check_tx; 1576 break; 1577 1578 case SO_PRIORITY: 1579 v.val = sk->sk_priority; 1580 break; 1581 1582 case SO_LINGER: 1583 lv = sizeof(v.ling); 1584 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1585 v.ling.l_linger = sk->sk_lingertime / HZ; 1586 break; 1587 1588 case SO_BSDCOMPAT: 1589 break; 1590 1591 case SO_TIMESTAMP_OLD: 1592 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1593 !sock_flag(sk, SOCK_TSTAMP_NEW) && 1594 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1595 break; 1596 1597 case SO_TIMESTAMPNS_OLD: 1598 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW); 1599 break; 1600 1601 case SO_TIMESTAMP_NEW: 1602 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW); 1603 break; 1604 1605 case SO_TIMESTAMPNS_NEW: 1606 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW); 1607 break; 1608 1609 case SO_TIMESTAMPING_OLD: 1610 lv = sizeof(v.timestamping); 1611 v.timestamping.flags = sk->sk_tsflags; 1612 v.timestamping.bind_phc = sk->sk_bind_phc; 1613 break; 1614 1615 case SO_RCVTIMEO_OLD: 1616 case SO_RCVTIMEO_NEW: 1617 lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname); 1618 break; 1619 1620 case SO_SNDTIMEO_OLD: 1621 case SO_SNDTIMEO_NEW: 1622 lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname); 1623 break; 1624 1625 case SO_RCVLOWAT: 1626 v.val = sk->sk_rcvlowat; 1627 break; 1628 1629 case SO_SNDLOWAT: 1630 v.val = 1; 1631 break; 1632 1633 case SO_PASSCRED: 1634 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1635 break; 1636 1637 case SO_PEERCRED: 1638 { 1639 struct ucred peercred; 1640 if (len > sizeof(peercred)) 1641 len = sizeof(peercred); 1642 1643 spin_lock(&sk->sk_peer_lock); 1644 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1645 spin_unlock(&sk->sk_peer_lock); 1646 1647 if (copy_to_user(optval, &peercred, len)) 1648 return -EFAULT; 1649 goto lenout; 1650 } 1651 1652 case SO_PEERGROUPS: 1653 { 1654 const struct cred *cred; 1655 int ret, n; 1656 1657 cred = sk_get_peer_cred(sk); 1658 if (!cred) 1659 return -ENODATA; 1660 1661 n = cred->group_info->ngroups; 1662 if (len < n * sizeof(gid_t)) { 1663 len = n * sizeof(gid_t); 1664 put_cred(cred); 1665 return put_user(len, optlen) ? -EFAULT : -ERANGE; 1666 } 1667 len = n * sizeof(gid_t); 1668 1669 ret = groups_to_user((gid_t __user *)optval, cred->group_info); 1670 put_cred(cred); 1671 if (ret) 1672 return ret; 1673 goto lenout; 1674 } 1675 1676 case SO_PEERNAME: 1677 { 1678 char address[128]; 1679 1680 lv = sock->ops->getname(sock, (struct sockaddr *)address, 2); 1681 if (lv < 0) 1682 return -ENOTCONN; 1683 if (lv < len) 1684 return -EINVAL; 1685 if (copy_to_user(optval, address, len)) 1686 return -EFAULT; 1687 goto lenout; 1688 } 1689 1690 /* Dubious BSD thing... Probably nobody even uses it, but 1691 * the UNIX standard wants it for whatever reason... -DaveM 1692 */ 1693 case SO_ACCEPTCONN: 1694 v.val = sk->sk_state == TCP_LISTEN; 1695 break; 1696 1697 case SO_PASSSEC: 1698 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1699 break; 1700 1701 case SO_PEERSEC: 1702 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1703 1704 case SO_MARK: 1705 v.val = sk->sk_mark; 1706 break; 1707 1708 case SO_RXQ_OVFL: 1709 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1710 break; 1711 1712 case SO_WIFI_STATUS: 1713 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1714 break; 1715 1716 case SO_PEEK_OFF: 1717 if (!sock->ops->set_peek_off) 1718 return -EOPNOTSUPP; 1719 1720 v.val = sk->sk_peek_off; 1721 break; 1722 case SO_NOFCS: 1723 v.val = sock_flag(sk, SOCK_NOFCS); 1724 break; 1725 1726 case SO_BINDTODEVICE: 1727 return sock_getbindtodevice(sk, optval, optlen, len); 1728 1729 case SO_GET_FILTER: 1730 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1731 if (len < 0) 1732 return len; 1733 1734 goto lenout; 1735 1736 case SO_LOCK_FILTER: 1737 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1738 break; 1739 1740 case SO_BPF_EXTENSIONS: 1741 v.val = bpf_tell_extensions(); 1742 break; 1743 1744 case SO_SELECT_ERR_QUEUE: 1745 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1746 break; 1747 1748 #ifdef CONFIG_NET_RX_BUSY_POLL 1749 case SO_BUSY_POLL: 1750 v.val = sk->sk_ll_usec; 1751 break; 1752 case SO_PREFER_BUSY_POLL: 1753 v.val = READ_ONCE(sk->sk_prefer_busy_poll); 1754 break; 1755 #endif 1756 1757 case SO_MAX_PACING_RATE: 1758 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) { 1759 lv = sizeof(v.ulval); 1760 v.ulval = sk->sk_max_pacing_rate; 1761 } else { 1762 /* 32bit version */ 1763 v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U); 1764 } 1765 break; 1766 1767 case SO_INCOMING_CPU: 1768 v.val = READ_ONCE(sk->sk_incoming_cpu); 1769 break; 1770 1771 case SO_MEMINFO: 1772 { 1773 u32 meminfo[SK_MEMINFO_VARS]; 1774 1775 sk_get_meminfo(sk, meminfo); 1776 1777 len = min_t(unsigned int, len, sizeof(meminfo)); 1778 if (copy_to_user(optval, &meminfo, len)) 1779 return -EFAULT; 1780 1781 goto lenout; 1782 } 1783 1784 #ifdef CONFIG_NET_RX_BUSY_POLL 1785 case SO_INCOMING_NAPI_ID: 1786 v.val = READ_ONCE(sk->sk_napi_id); 1787 1788 /* aggregate non-NAPI IDs down to 0 */ 1789 if (v.val < MIN_NAPI_ID) 1790 v.val = 0; 1791 1792 break; 1793 #endif 1794 1795 case SO_COOKIE: 1796 lv = sizeof(u64); 1797 if (len < lv) 1798 return -EINVAL; 1799 v.val64 = sock_gen_cookie(sk); 1800 break; 1801 1802 case SO_ZEROCOPY: 1803 v.val = sock_flag(sk, SOCK_ZEROCOPY); 1804 break; 1805 1806 case SO_TXTIME: 1807 lv = sizeof(v.txtime); 1808 v.txtime.clockid = sk->sk_clockid; 1809 v.txtime.flags |= sk->sk_txtime_deadline_mode ? 1810 SOF_TXTIME_DEADLINE_MODE : 0; 1811 v.txtime.flags |= sk->sk_txtime_report_errors ? 1812 SOF_TXTIME_REPORT_ERRORS : 0; 1813 break; 1814 1815 case SO_BINDTOIFINDEX: 1816 v.val = sk->sk_bound_dev_if; 1817 break; 1818 1819 case SO_NETNS_COOKIE: 1820 lv = sizeof(u64); 1821 if (len != lv) 1822 return -EINVAL; 1823 v.val64 = sock_net(sk)->net_cookie; 1824 break; 1825 1826 case SO_BUF_LOCK: 1827 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK; 1828 break; 1829 1830 case SO_RESERVE_MEM: 1831 v.val = sk->sk_reserved_mem; 1832 break; 1833 1834 default: 1835 /* We implement the SO_SNDLOWAT etc to not be settable 1836 * (1003.1g 7). 1837 */ 1838 return -ENOPROTOOPT; 1839 } 1840 1841 if (len > lv) 1842 len = lv; 1843 if (copy_to_user(optval, &v, len)) 1844 return -EFAULT; 1845 lenout: 1846 if (put_user(len, optlen)) 1847 return -EFAULT; 1848 return 0; 1849 } 1850 1851 /* 1852 * Initialize an sk_lock. 1853 * 1854 * (We also register the sk_lock with the lock validator.) 1855 */ 1856 static inline void sock_lock_init(struct sock *sk) 1857 { 1858 if (sk->sk_kern_sock) 1859 sock_lock_init_class_and_name( 1860 sk, 1861 af_family_kern_slock_key_strings[sk->sk_family], 1862 af_family_kern_slock_keys + sk->sk_family, 1863 af_family_kern_key_strings[sk->sk_family], 1864 af_family_kern_keys + sk->sk_family); 1865 else 1866 sock_lock_init_class_and_name( 1867 sk, 1868 af_family_slock_key_strings[sk->sk_family], 1869 af_family_slock_keys + sk->sk_family, 1870 af_family_key_strings[sk->sk_family], 1871 af_family_keys + sk->sk_family); 1872 } 1873 1874 /* 1875 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1876 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1877 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1878 */ 1879 static void sock_copy(struct sock *nsk, const struct sock *osk) 1880 { 1881 const struct proto *prot = READ_ONCE(osk->sk_prot); 1882 #ifdef CONFIG_SECURITY_NETWORK 1883 void *sptr = nsk->sk_security; 1884 #endif 1885 1886 /* If we move sk_tx_queue_mapping out of the private section, 1887 * we must check if sk_tx_queue_clear() is called after 1888 * sock_copy() in sk_clone_lock(). 1889 */ 1890 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) < 1891 offsetof(struct sock, sk_dontcopy_begin) || 1892 offsetof(struct sock, sk_tx_queue_mapping) >= 1893 offsetof(struct sock, sk_dontcopy_end)); 1894 1895 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1896 1897 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1898 prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1899 1900 #ifdef CONFIG_SECURITY_NETWORK 1901 nsk->sk_security = sptr; 1902 security_sk_clone(osk, nsk); 1903 #endif 1904 } 1905 1906 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1907 int family) 1908 { 1909 struct sock *sk; 1910 struct kmem_cache *slab; 1911 1912 slab = prot->slab; 1913 if (slab != NULL) { 1914 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1915 if (!sk) 1916 return sk; 1917 if (want_init_on_alloc(priority)) 1918 sk_prot_clear_nulls(sk, prot->obj_size); 1919 } else 1920 sk = kmalloc(prot->obj_size, priority); 1921 1922 if (sk != NULL) { 1923 if (security_sk_alloc(sk, family, priority)) 1924 goto out_free; 1925 1926 if (!try_module_get(prot->owner)) 1927 goto out_free_sec; 1928 } 1929 1930 return sk; 1931 1932 out_free_sec: 1933 security_sk_free(sk); 1934 out_free: 1935 if (slab != NULL) 1936 kmem_cache_free(slab, sk); 1937 else 1938 kfree(sk); 1939 return NULL; 1940 } 1941 1942 static void sk_prot_free(struct proto *prot, struct sock *sk) 1943 { 1944 struct kmem_cache *slab; 1945 struct module *owner; 1946 1947 owner = prot->owner; 1948 slab = prot->slab; 1949 1950 cgroup_sk_free(&sk->sk_cgrp_data); 1951 mem_cgroup_sk_free(sk); 1952 security_sk_free(sk); 1953 if (slab != NULL) 1954 kmem_cache_free(slab, sk); 1955 else 1956 kfree(sk); 1957 module_put(owner); 1958 } 1959 1960 /** 1961 * sk_alloc - All socket objects are allocated here 1962 * @net: the applicable net namespace 1963 * @family: protocol family 1964 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1965 * @prot: struct proto associated with this new sock instance 1966 * @kern: is this to be a kernel socket? 1967 */ 1968 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1969 struct proto *prot, int kern) 1970 { 1971 struct sock *sk; 1972 1973 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1974 if (sk) { 1975 sk->sk_family = family; 1976 /* 1977 * See comment in struct sock definition to understand 1978 * why we need sk_prot_creator -acme 1979 */ 1980 sk->sk_prot = sk->sk_prot_creator = prot; 1981 sk->sk_kern_sock = kern; 1982 sock_lock_init(sk); 1983 sk->sk_net_refcnt = kern ? 0 : 1; 1984 if (likely(sk->sk_net_refcnt)) { 1985 get_net(net); 1986 sock_inuse_add(net, 1); 1987 } 1988 1989 sock_net_set(sk, net); 1990 refcount_set(&sk->sk_wmem_alloc, 1); 1991 1992 mem_cgroup_sk_alloc(sk); 1993 cgroup_sk_alloc(&sk->sk_cgrp_data); 1994 sock_update_classid(&sk->sk_cgrp_data); 1995 sock_update_netprioidx(&sk->sk_cgrp_data); 1996 sk_tx_queue_clear(sk); 1997 } 1998 1999 return sk; 2000 } 2001 EXPORT_SYMBOL(sk_alloc); 2002 2003 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 2004 * grace period. This is the case for UDP sockets and TCP listeners. 2005 */ 2006 static void __sk_destruct(struct rcu_head *head) 2007 { 2008 struct sock *sk = container_of(head, struct sock, sk_rcu); 2009 struct sk_filter *filter; 2010 2011 if (sk->sk_destruct) 2012 sk->sk_destruct(sk); 2013 2014 filter = rcu_dereference_check(sk->sk_filter, 2015 refcount_read(&sk->sk_wmem_alloc) == 0); 2016 if (filter) { 2017 sk_filter_uncharge(sk, filter); 2018 RCU_INIT_POINTER(sk->sk_filter, NULL); 2019 } 2020 2021 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 2022 2023 #ifdef CONFIG_BPF_SYSCALL 2024 bpf_sk_storage_free(sk); 2025 #endif 2026 2027 if (atomic_read(&sk->sk_omem_alloc)) 2028 pr_debug("%s: optmem leakage (%d bytes) detected\n", 2029 __func__, atomic_read(&sk->sk_omem_alloc)); 2030 2031 if (sk->sk_frag.page) { 2032 put_page(sk->sk_frag.page); 2033 sk->sk_frag.page = NULL; 2034 } 2035 2036 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */ 2037 put_cred(sk->sk_peer_cred); 2038 put_pid(sk->sk_peer_pid); 2039 2040 if (likely(sk->sk_net_refcnt)) 2041 put_net(sock_net(sk)); 2042 sk_prot_free(sk->sk_prot_creator, sk); 2043 } 2044 2045 void sk_destruct(struct sock *sk) 2046 { 2047 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE); 2048 2049 if (rcu_access_pointer(sk->sk_reuseport_cb)) { 2050 reuseport_detach_sock(sk); 2051 use_call_rcu = true; 2052 } 2053 2054 if (use_call_rcu) 2055 call_rcu(&sk->sk_rcu, __sk_destruct); 2056 else 2057 __sk_destruct(&sk->sk_rcu); 2058 } 2059 2060 static void __sk_free(struct sock *sk) 2061 { 2062 if (likely(sk->sk_net_refcnt)) 2063 sock_inuse_add(sock_net(sk), -1); 2064 2065 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk))) 2066 sock_diag_broadcast_destroy(sk); 2067 else 2068 sk_destruct(sk); 2069 } 2070 2071 void sk_free(struct sock *sk) 2072 { 2073 /* 2074 * We subtract one from sk_wmem_alloc and can know if 2075 * some packets are still in some tx queue. 2076 * If not null, sock_wfree() will call __sk_free(sk) later 2077 */ 2078 if (refcount_dec_and_test(&sk->sk_wmem_alloc)) 2079 __sk_free(sk); 2080 } 2081 EXPORT_SYMBOL(sk_free); 2082 2083 static void sk_init_common(struct sock *sk) 2084 { 2085 skb_queue_head_init(&sk->sk_receive_queue); 2086 skb_queue_head_init(&sk->sk_write_queue); 2087 skb_queue_head_init(&sk->sk_error_queue); 2088 2089 rwlock_init(&sk->sk_callback_lock); 2090 lockdep_set_class_and_name(&sk->sk_receive_queue.lock, 2091 af_rlock_keys + sk->sk_family, 2092 af_family_rlock_key_strings[sk->sk_family]); 2093 lockdep_set_class_and_name(&sk->sk_write_queue.lock, 2094 af_wlock_keys + sk->sk_family, 2095 af_family_wlock_key_strings[sk->sk_family]); 2096 lockdep_set_class_and_name(&sk->sk_error_queue.lock, 2097 af_elock_keys + sk->sk_family, 2098 af_family_elock_key_strings[sk->sk_family]); 2099 lockdep_set_class_and_name(&sk->sk_callback_lock, 2100 af_callback_keys + sk->sk_family, 2101 af_family_clock_key_strings[sk->sk_family]); 2102 } 2103 2104 /** 2105 * sk_clone_lock - clone a socket, and lock its clone 2106 * @sk: the socket to clone 2107 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 2108 * 2109 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 2110 */ 2111 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 2112 { 2113 struct proto *prot = READ_ONCE(sk->sk_prot); 2114 struct sk_filter *filter; 2115 bool is_charged = true; 2116 struct sock *newsk; 2117 2118 newsk = sk_prot_alloc(prot, priority, sk->sk_family); 2119 if (!newsk) 2120 goto out; 2121 2122 sock_copy(newsk, sk); 2123 2124 newsk->sk_prot_creator = prot; 2125 2126 /* SANITY */ 2127 if (likely(newsk->sk_net_refcnt)) 2128 get_net(sock_net(newsk)); 2129 sk_node_init(&newsk->sk_node); 2130 sock_lock_init(newsk); 2131 bh_lock_sock(newsk); 2132 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 2133 newsk->sk_backlog.len = 0; 2134 2135 atomic_set(&newsk->sk_rmem_alloc, 0); 2136 2137 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */ 2138 refcount_set(&newsk->sk_wmem_alloc, 1); 2139 2140 atomic_set(&newsk->sk_omem_alloc, 0); 2141 sk_init_common(newsk); 2142 2143 newsk->sk_dst_cache = NULL; 2144 newsk->sk_dst_pending_confirm = 0; 2145 newsk->sk_wmem_queued = 0; 2146 newsk->sk_forward_alloc = 0; 2147 newsk->sk_reserved_mem = 0; 2148 atomic_set(&newsk->sk_drops, 0); 2149 newsk->sk_send_head = NULL; 2150 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 2151 atomic_set(&newsk->sk_zckey, 0); 2152 2153 sock_reset_flag(newsk, SOCK_DONE); 2154 2155 /* sk->sk_memcg will be populated at accept() time */ 2156 newsk->sk_memcg = NULL; 2157 2158 cgroup_sk_clone(&newsk->sk_cgrp_data); 2159 2160 rcu_read_lock(); 2161 filter = rcu_dereference(sk->sk_filter); 2162 if (filter != NULL) 2163 /* though it's an empty new sock, the charging may fail 2164 * if sysctl_optmem_max was changed between creation of 2165 * original socket and cloning 2166 */ 2167 is_charged = sk_filter_charge(newsk, filter); 2168 RCU_INIT_POINTER(newsk->sk_filter, filter); 2169 rcu_read_unlock(); 2170 2171 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 2172 /* We need to make sure that we don't uncharge the new 2173 * socket if we couldn't charge it in the first place 2174 * as otherwise we uncharge the parent's filter. 2175 */ 2176 if (!is_charged) 2177 RCU_INIT_POINTER(newsk->sk_filter, NULL); 2178 sk_free_unlock_clone(newsk); 2179 newsk = NULL; 2180 goto out; 2181 } 2182 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 2183 2184 if (bpf_sk_storage_clone(sk, newsk)) { 2185 sk_free_unlock_clone(newsk); 2186 newsk = NULL; 2187 goto out; 2188 } 2189 2190 /* Clear sk_user_data if parent had the pointer tagged 2191 * as not suitable for copying when cloning. 2192 */ 2193 if (sk_user_data_is_nocopy(newsk)) 2194 newsk->sk_user_data = NULL; 2195 2196 newsk->sk_err = 0; 2197 newsk->sk_err_soft = 0; 2198 newsk->sk_priority = 0; 2199 newsk->sk_incoming_cpu = raw_smp_processor_id(); 2200 if (likely(newsk->sk_net_refcnt)) 2201 sock_inuse_add(sock_net(newsk), 1); 2202 2203 /* Before updating sk_refcnt, we must commit prior changes to memory 2204 * (Documentation/RCU/rculist_nulls.rst for details) 2205 */ 2206 smp_wmb(); 2207 refcount_set(&newsk->sk_refcnt, 2); 2208 2209 /* Increment the counter in the same struct proto as the master 2210 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 2211 * is the same as sk->sk_prot->socks, as this field was copied 2212 * with memcpy). 2213 * 2214 * This _changes_ the previous behaviour, where 2215 * tcp_create_openreq_child always was incrementing the 2216 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 2217 * to be taken into account in all callers. -acme 2218 */ 2219 sk_refcnt_debug_inc(newsk); 2220 sk_set_socket(newsk, NULL); 2221 sk_tx_queue_clear(newsk); 2222 RCU_INIT_POINTER(newsk->sk_wq, NULL); 2223 2224 if (newsk->sk_prot->sockets_allocated) 2225 sk_sockets_allocated_inc(newsk); 2226 2227 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP) 2228 net_enable_timestamp(); 2229 out: 2230 return newsk; 2231 } 2232 EXPORT_SYMBOL_GPL(sk_clone_lock); 2233 2234 void sk_free_unlock_clone(struct sock *sk) 2235 { 2236 /* It is still raw copy of parent, so invalidate 2237 * destructor and make plain sk_free() */ 2238 sk->sk_destruct = NULL; 2239 bh_unlock_sock(sk); 2240 sk_free(sk); 2241 } 2242 EXPORT_SYMBOL_GPL(sk_free_unlock_clone); 2243 2244 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 2245 { 2246 u32 max_segs = 1; 2247 2248 sk_dst_set(sk, dst); 2249 sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps; 2250 if (sk->sk_route_caps & NETIF_F_GSO) 2251 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 2252 sk->sk_route_caps &= ~sk->sk_route_nocaps; 2253 if (sk_can_gso(sk)) { 2254 if (dst->header_len && !xfrm_dst_offload_ok(dst)) { 2255 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2256 } else { 2257 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 2258 sk->sk_gso_max_size = dst->dev->gso_max_size; 2259 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 2260 } 2261 } 2262 sk->sk_gso_max_segs = max_segs; 2263 } 2264 EXPORT_SYMBOL_GPL(sk_setup_caps); 2265 2266 /* 2267 * Simple resource managers for sockets. 2268 */ 2269 2270 2271 /* 2272 * Write buffer destructor automatically called from kfree_skb. 2273 */ 2274 void sock_wfree(struct sk_buff *skb) 2275 { 2276 struct sock *sk = skb->sk; 2277 unsigned int len = skb->truesize; 2278 2279 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 2280 /* 2281 * Keep a reference on sk_wmem_alloc, this will be released 2282 * after sk_write_space() call 2283 */ 2284 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); 2285 sk->sk_write_space(sk); 2286 len = 1; 2287 } 2288 /* 2289 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 2290 * could not do because of in-flight packets 2291 */ 2292 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc)) 2293 __sk_free(sk); 2294 } 2295 EXPORT_SYMBOL(sock_wfree); 2296 2297 /* This variant of sock_wfree() is used by TCP, 2298 * since it sets SOCK_USE_WRITE_QUEUE. 2299 */ 2300 void __sock_wfree(struct sk_buff *skb) 2301 { 2302 struct sock *sk = skb->sk; 2303 2304 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 2305 __sk_free(sk); 2306 } 2307 2308 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 2309 { 2310 skb_orphan(skb); 2311 skb->sk = sk; 2312 #ifdef CONFIG_INET 2313 if (unlikely(!sk_fullsock(sk))) { 2314 skb->destructor = sock_edemux; 2315 sock_hold(sk); 2316 return; 2317 } 2318 #endif 2319 skb->destructor = sock_wfree; 2320 skb_set_hash_from_sk(skb, sk); 2321 /* 2322 * We used to take a refcount on sk, but following operation 2323 * is enough to guarantee sk_free() wont free this sock until 2324 * all in-flight packets are completed 2325 */ 2326 refcount_add(skb->truesize, &sk->sk_wmem_alloc); 2327 } 2328 EXPORT_SYMBOL(skb_set_owner_w); 2329 2330 static bool can_skb_orphan_partial(const struct sk_buff *skb) 2331 { 2332 #ifdef CONFIG_TLS_DEVICE 2333 /* Drivers depend on in-order delivery for crypto offload, 2334 * partial orphan breaks out-of-order-OK logic. 2335 */ 2336 if (skb->decrypted) 2337 return false; 2338 #endif 2339 return (skb->destructor == sock_wfree || 2340 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree)); 2341 } 2342 2343 /* This helper is used by netem, as it can hold packets in its 2344 * delay queue. We want to allow the owner socket to send more 2345 * packets, as if they were already TX completed by a typical driver. 2346 * But we also want to keep skb->sk set because some packet schedulers 2347 * rely on it (sch_fq for example). 2348 */ 2349 void skb_orphan_partial(struct sk_buff *skb) 2350 { 2351 if (skb_is_tcp_pure_ack(skb)) 2352 return; 2353 2354 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk)) 2355 return; 2356 2357 skb_orphan(skb); 2358 } 2359 EXPORT_SYMBOL(skb_orphan_partial); 2360 2361 /* 2362 * Read buffer destructor automatically called from kfree_skb. 2363 */ 2364 void sock_rfree(struct sk_buff *skb) 2365 { 2366 struct sock *sk = skb->sk; 2367 unsigned int len = skb->truesize; 2368 2369 atomic_sub(len, &sk->sk_rmem_alloc); 2370 sk_mem_uncharge(sk, len); 2371 } 2372 EXPORT_SYMBOL(sock_rfree); 2373 2374 /* 2375 * Buffer destructor for skbs that are not used directly in read or write 2376 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 2377 */ 2378 void sock_efree(struct sk_buff *skb) 2379 { 2380 sock_put(skb->sk); 2381 } 2382 EXPORT_SYMBOL(sock_efree); 2383 2384 /* Buffer destructor for prefetch/receive path where reference count may 2385 * not be held, e.g. for listen sockets. 2386 */ 2387 #ifdef CONFIG_INET 2388 void sock_pfree(struct sk_buff *skb) 2389 { 2390 if (sk_is_refcounted(skb->sk)) 2391 sock_gen_put(skb->sk); 2392 } 2393 EXPORT_SYMBOL(sock_pfree); 2394 #endif /* CONFIG_INET */ 2395 2396 kuid_t sock_i_uid(struct sock *sk) 2397 { 2398 kuid_t uid; 2399 2400 read_lock_bh(&sk->sk_callback_lock); 2401 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 2402 read_unlock_bh(&sk->sk_callback_lock); 2403 return uid; 2404 } 2405 EXPORT_SYMBOL(sock_i_uid); 2406 2407 unsigned long sock_i_ino(struct sock *sk) 2408 { 2409 unsigned long ino; 2410 2411 read_lock_bh(&sk->sk_callback_lock); 2412 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 2413 read_unlock_bh(&sk->sk_callback_lock); 2414 return ino; 2415 } 2416 EXPORT_SYMBOL(sock_i_ino); 2417 2418 /* 2419 * Allocate a skb from the socket's send buffer. 2420 */ 2421 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 2422 gfp_t priority) 2423 { 2424 if (force || 2425 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) { 2426 struct sk_buff *skb = alloc_skb(size, priority); 2427 2428 if (skb) { 2429 skb_set_owner_w(skb, sk); 2430 return skb; 2431 } 2432 } 2433 return NULL; 2434 } 2435 EXPORT_SYMBOL(sock_wmalloc); 2436 2437 static void sock_ofree(struct sk_buff *skb) 2438 { 2439 struct sock *sk = skb->sk; 2440 2441 atomic_sub(skb->truesize, &sk->sk_omem_alloc); 2442 } 2443 2444 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 2445 gfp_t priority) 2446 { 2447 struct sk_buff *skb; 2448 2449 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */ 2450 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) > 2451 sysctl_optmem_max) 2452 return NULL; 2453 2454 skb = alloc_skb(size, priority); 2455 if (!skb) 2456 return NULL; 2457 2458 atomic_add(skb->truesize, &sk->sk_omem_alloc); 2459 skb->sk = sk; 2460 skb->destructor = sock_ofree; 2461 return skb; 2462 } 2463 2464 /* 2465 * Allocate a memory block from the socket's option memory buffer. 2466 */ 2467 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 2468 { 2469 if ((unsigned int)size <= sysctl_optmem_max && 2470 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 2471 void *mem; 2472 /* First do the add, to avoid the race if kmalloc 2473 * might sleep. 2474 */ 2475 atomic_add(size, &sk->sk_omem_alloc); 2476 mem = kmalloc(size, priority); 2477 if (mem) 2478 return mem; 2479 atomic_sub(size, &sk->sk_omem_alloc); 2480 } 2481 return NULL; 2482 } 2483 EXPORT_SYMBOL(sock_kmalloc); 2484 2485 /* Free an option memory block. Note, we actually want the inline 2486 * here as this allows gcc to detect the nullify and fold away the 2487 * condition entirely. 2488 */ 2489 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 2490 const bool nullify) 2491 { 2492 if (WARN_ON_ONCE(!mem)) 2493 return; 2494 if (nullify) 2495 kfree_sensitive(mem); 2496 else 2497 kfree(mem); 2498 atomic_sub(size, &sk->sk_omem_alloc); 2499 } 2500 2501 void sock_kfree_s(struct sock *sk, void *mem, int size) 2502 { 2503 __sock_kfree_s(sk, mem, size, false); 2504 } 2505 EXPORT_SYMBOL(sock_kfree_s); 2506 2507 void sock_kzfree_s(struct sock *sk, void *mem, int size) 2508 { 2509 __sock_kfree_s(sk, mem, size, true); 2510 } 2511 EXPORT_SYMBOL(sock_kzfree_s); 2512 2513 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 2514 I think, these locks should be removed for datagram sockets. 2515 */ 2516 static long sock_wait_for_wmem(struct sock *sk, long timeo) 2517 { 2518 DEFINE_WAIT(wait); 2519 2520 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2521 for (;;) { 2522 if (!timeo) 2523 break; 2524 if (signal_pending(current)) 2525 break; 2526 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2527 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 2528 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) 2529 break; 2530 if (sk->sk_shutdown & SEND_SHUTDOWN) 2531 break; 2532 if (sk->sk_err) 2533 break; 2534 timeo = schedule_timeout(timeo); 2535 } 2536 finish_wait(sk_sleep(sk), &wait); 2537 return timeo; 2538 } 2539 2540 2541 /* 2542 * Generic send/receive buffer handlers 2543 */ 2544 2545 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 2546 unsigned long data_len, int noblock, 2547 int *errcode, int max_page_order) 2548 { 2549 struct sk_buff *skb; 2550 long timeo; 2551 int err; 2552 2553 timeo = sock_sndtimeo(sk, noblock); 2554 for (;;) { 2555 err = sock_error(sk); 2556 if (err != 0) 2557 goto failure; 2558 2559 err = -EPIPE; 2560 if (sk->sk_shutdown & SEND_SHUTDOWN) 2561 goto failure; 2562 2563 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf)) 2564 break; 2565 2566 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2567 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2568 err = -EAGAIN; 2569 if (!timeo) 2570 goto failure; 2571 if (signal_pending(current)) 2572 goto interrupted; 2573 timeo = sock_wait_for_wmem(sk, timeo); 2574 } 2575 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 2576 errcode, sk->sk_allocation); 2577 if (skb) 2578 skb_set_owner_w(skb, sk); 2579 return skb; 2580 2581 interrupted: 2582 err = sock_intr_errno(timeo); 2583 failure: 2584 *errcode = err; 2585 return NULL; 2586 } 2587 EXPORT_SYMBOL(sock_alloc_send_pskb); 2588 2589 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 2590 int noblock, int *errcode) 2591 { 2592 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 2593 } 2594 EXPORT_SYMBOL(sock_alloc_send_skb); 2595 2596 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 2597 struct sockcm_cookie *sockc) 2598 { 2599 u32 tsflags; 2600 2601 switch (cmsg->cmsg_type) { 2602 case SO_MARK: 2603 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 2604 return -EPERM; 2605 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2606 return -EINVAL; 2607 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 2608 break; 2609 case SO_TIMESTAMPING_OLD: 2610 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2611 return -EINVAL; 2612 2613 tsflags = *(u32 *)CMSG_DATA(cmsg); 2614 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 2615 return -EINVAL; 2616 2617 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 2618 sockc->tsflags |= tsflags; 2619 break; 2620 case SCM_TXTIME: 2621 if (!sock_flag(sk, SOCK_TXTIME)) 2622 return -EINVAL; 2623 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64))) 2624 return -EINVAL; 2625 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg)); 2626 break; 2627 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 2628 case SCM_RIGHTS: 2629 case SCM_CREDENTIALS: 2630 break; 2631 default: 2632 return -EINVAL; 2633 } 2634 return 0; 2635 } 2636 EXPORT_SYMBOL(__sock_cmsg_send); 2637 2638 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 2639 struct sockcm_cookie *sockc) 2640 { 2641 struct cmsghdr *cmsg; 2642 int ret; 2643 2644 for_each_cmsghdr(cmsg, msg) { 2645 if (!CMSG_OK(msg, cmsg)) 2646 return -EINVAL; 2647 if (cmsg->cmsg_level != SOL_SOCKET) 2648 continue; 2649 ret = __sock_cmsg_send(sk, msg, cmsg, sockc); 2650 if (ret) 2651 return ret; 2652 } 2653 return 0; 2654 } 2655 EXPORT_SYMBOL(sock_cmsg_send); 2656 2657 static void sk_enter_memory_pressure(struct sock *sk) 2658 { 2659 if (!sk->sk_prot->enter_memory_pressure) 2660 return; 2661 2662 sk->sk_prot->enter_memory_pressure(sk); 2663 } 2664 2665 static void sk_leave_memory_pressure(struct sock *sk) 2666 { 2667 if (sk->sk_prot->leave_memory_pressure) { 2668 sk->sk_prot->leave_memory_pressure(sk); 2669 } else { 2670 unsigned long *memory_pressure = sk->sk_prot->memory_pressure; 2671 2672 if (memory_pressure && READ_ONCE(*memory_pressure)) 2673 WRITE_ONCE(*memory_pressure, 0); 2674 } 2675 } 2676 2677 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2678 2679 /** 2680 * skb_page_frag_refill - check that a page_frag contains enough room 2681 * @sz: minimum size of the fragment we want to get 2682 * @pfrag: pointer to page_frag 2683 * @gfp: priority for memory allocation 2684 * 2685 * Note: While this allocator tries to use high order pages, there is 2686 * no guarantee that allocations succeed. Therefore, @sz MUST be 2687 * less or equal than PAGE_SIZE. 2688 */ 2689 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 2690 { 2691 if (pfrag->page) { 2692 if (page_ref_count(pfrag->page) == 1) { 2693 pfrag->offset = 0; 2694 return true; 2695 } 2696 if (pfrag->offset + sz <= pfrag->size) 2697 return true; 2698 put_page(pfrag->page); 2699 } 2700 2701 pfrag->offset = 0; 2702 if (SKB_FRAG_PAGE_ORDER && 2703 !static_branch_unlikely(&net_high_order_alloc_disable_key)) { 2704 /* Avoid direct reclaim but allow kswapd to wake */ 2705 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 2706 __GFP_COMP | __GFP_NOWARN | 2707 __GFP_NORETRY, 2708 SKB_FRAG_PAGE_ORDER); 2709 if (likely(pfrag->page)) { 2710 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 2711 return true; 2712 } 2713 } 2714 pfrag->page = alloc_page(gfp); 2715 if (likely(pfrag->page)) { 2716 pfrag->size = PAGE_SIZE; 2717 return true; 2718 } 2719 return false; 2720 } 2721 EXPORT_SYMBOL(skb_page_frag_refill); 2722 2723 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 2724 { 2725 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 2726 return true; 2727 2728 sk_enter_memory_pressure(sk); 2729 sk_stream_moderate_sndbuf(sk); 2730 return false; 2731 } 2732 EXPORT_SYMBOL(sk_page_frag_refill); 2733 2734 void __lock_sock(struct sock *sk) 2735 __releases(&sk->sk_lock.slock) 2736 __acquires(&sk->sk_lock.slock) 2737 { 2738 DEFINE_WAIT(wait); 2739 2740 for (;;) { 2741 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2742 TASK_UNINTERRUPTIBLE); 2743 spin_unlock_bh(&sk->sk_lock.slock); 2744 schedule(); 2745 spin_lock_bh(&sk->sk_lock.slock); 2746 if (!sock_owned_by_user(sk)) 2747 break; 2748 } 2749 finish_wait(&sk->sk_lock.wq, &wait); 2750 } 2751 2752 void __release_sock(struct sock *sk) 2753 __releases(&sk->sk_lock.slock) 2754 __acquires(&sk->sk_lock.slock) 2755 { 2756 struct sk_buff *skb, *next; 2757 2758 while ((skb = sk->sk_backlog.head) != NULL) { 2759 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 2760 2761 spin_unlock_bh(&sk->sk_lock.slock); 2762 2763 do { 2764 next = skb->next; 2765 prefetch(next); 2766 WARN_ON_ONCE(skb_dst_is_noref(skb)); 2767 skb_mark_not_on_list(skb); 2768 sk_backlog_rcv(sk, skb); 2769 2770 cond_resched(); 2771 2772 skb = next; 2773 } while (skb != NULL); 2774 2775 spin_lock_bh(&sk->sk_lock.slock); 2776 } 2777 2778 /* 2779 * Doing the zeroing here guarantee we can not loop forever 2780 * while a wild producer attempts to flood us. 2781 */ 2782 sk->sk_backlog.len = 0; 2783 } 2784 2785 void __sk_flush_backlog(struct sock *sk) 2786 { 2787 spin_lock_bh(&sk->sk_lock.slock); 2788 __release_sock(sk); 2789 spin_unlock_bh(&sk->sk_lock.slock); 2790 } 2791 2792 /** 2793 * sk_wait_data - wait for data to arrive at sk_receive_queue 2794 * @sk: sock to wait on 2795 * @timeo: for how long 2796 * @skb: last skb seen on sk_receive_queue 2797 * 2798 * Now socket state including sk->sk_err is changed only under lock, 2799 * hence we may omit checks after joining wait queue. 2800 * We check receive queue before schedule() only as optimization; 2801 * it is very likely that release_sock() added new data. 2802 */ 2803 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 2804 { 2805 DEFINE_WAIT_FUNC(wait, woken_wake_function); 2806 int rc; 2807 2808 add_wait_queue(sk_sleep(sk), &wait); 2809 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2810 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); 2811 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2812 remove_wait_queue(sk_sleep(sk), &wait); 2813 return rc; 2814 } 2815 EXPORT_SYMBOL(sk_wait_data); 2816 2817 /** 2818 * __sk_mem_raise_allocated - increase memory_allocated 2819 * @sk: socket 2820 * @size: memory size to allocate 2821 * @amt: pages to allocate 2822 * @kind: allocation type 2823 * 2824 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc 2825 */ 2826 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) 2827 { 2828 struct proto *prot = sk->sk_prot; 2829 long allocated = sk_memory_allocated_add(sk, amt); 2830 bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg; 2831 bool charged = true; 2832 2833 if (memcg_charge && 2834 !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt, 2835 gfp_memcg_charge()))) 2836 goto suppress_allocation; 2837 2838 /* Under limit. */ 2839 if (allocated <= sk_prot_mem_limits(sk, 0)) { 2840 sk_leave_memory_pressure(sk); 2841 return 1; 2842 } 2843 2844 /* Under pressure. */ 2845 if (allocated > sk_prot_mem_limits(sk, 1)) 2846 sk_enter_memory_pressure(sk); 2847 2848 /* Over hard limit. */ 2849 if (allocated > sk_prot_mem_limits(sk, 2)) 2850 goto suppress_allocation; 2851 2852 /* guarantee minimum buffer size under pressure */ 2853 if (kind == SK_MEM_RECV) { 2854 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot)) 2855 return 1; 2856 2857 } else { /* SK_MEM_SEND */ 2858 int wmem0 = sk_get_wmem0(sk, prot); 2859 2860 if (sk->sk_type == SOCK_STREAM) { 2861 if (sk->sk_wmem_queued < wmem0) 2862 return 1; 2863 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) { 2864 return 1; 2865 } 2866 } 2867 2868 if (sk_has_memory_pressure(sk)) { 2869 u64 alloc; 2870 2871 if (!sk_under_memory_pressure(sk)) 2872 return 1; 2873 alloc = sk_sockets_allocated_read_positive(sk); 2874 if (sk_prot_mem_limits(sk, 2) > alloc * 2875 sk_mem_pages(sk->sk_wmem_queued + 2876 atomic_read(&sk->sk_rmem_alloc) + 2877 sk->sk_forward_alloc)) 2878 return 1; 2879 } 2880 2881 suppress_allocation: 2882 2883 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2884 sk_stream_moderate_sndbuf(sk); 2885 2886 /* Fail only if socket is _under_ its sndbuf. 2887 * In this case we cannot block, so that we have to fail. 2888 */ 2889 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) { 2890 /* Force charge with __GFP_NOFAIL */ 2891 if (memcg_charge && !charged) { 2892 mem_cgroup_charge_skmem(sk->sk_memcg, amt, 2893 gfp_memcg_charge() | __GFP_NOFAIL); 2894 } 2895 return 1; 2896 } 2897 } 2898 2899 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) 2900 trace_sock_exceed_buf_limit(sk, prot, allocated, kind); 2901 2902 sk_memory_allocated_sub(sk, amt); 2903 2904 if (memcg_charge && charged) 2905 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); 2906 2907 return 0; 2908 } 2909 EXPORT_SYMBOL(__sk_mem_raise_allocated); 2910 2911 /** 2912 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 2913 * @sk: socket 2914 * @size: memory size to allocate 2915 * @kind: allocation type 2916 * 2917 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 2918 * rmem allocation. This function assumes that protocols which have 2919 * memory_pressure use sk_wmem_queued as write buffer accounting. 2920 */ 2921 int __sk_mem_schedule(struct sock *sk, int size, int kind) 2922 { 2923 int ret, amt = sk_mem_pages(size); 2924 2925 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT; 2926 ret = __sk_mem_raise_allocated(sk, size, amt, kind); 2927 if (!ret) 2928 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT; 2929 return ret; 2930 } 2931 EXPORT_SYMBOL(__sk_mem_schedule); 2932 2933 /** 2934 * __sk_mem_reduce_allocated - reclaim memory_allocated 2935 * @sk: socket 2936 * @amount: number of quanta 2937 * 2938 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc 2939 */ 2940 void __sk_mem_reduce_allocated(struct sock *sk, int amount) 2941 { 2942 sk_memory_allocated_sub(sk, amount); 2943 2944 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2945 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 2946 2947 if (sk_under_memory_pressure(sk) && 2948 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2949 sk_leave_memory_pressure(sk); 2950 } 2951 EXPORT_SYMBOL(__sk_mem_reduce_allocated); 2952 2953 /** 2954 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated 2955 * @sk: socket 2956 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2957 */ 2958 void __sk_mem_reclaim(struct sock *sk, int amount) 2959 { 2960 amount >>= SK_MEM_QUANTUM_SHIFT; 2961 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2962 __sk_mem_reduce_allocated(sk, amount); 2963 } 2964 EXPORT_SYMBOL(__sk_mem_reclaim); 2965 2966 int sk_set_peek_off(struct sock *sk, int val) 2967 { 2968 sk->sk_peek_off = val; 2969 return 0; 2970 } 2971 EXPORT_SYMBOL_GPL(sk_set_peek_off); 2972 2973 /* 2974 * Set of default routines for initialising struct proto_ops when 2975 * the protocol does not support a particular function. In certain 2976 * cases where it makes no sense for a protocol to have a "do nothing" 2977 * function, some default processing is provided. 2978 */ 2979 2980 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2981 { 2982 return -EOPNOTSUPP; 2983 } 2984 EXPORT_SYMBOL(sock_no_bind); 2985 2986 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2987 int len, int flags) 2988 { 2989 return -EOPNOTSUPP; 2990 } 2991 EXPORT_SYMBOL(sock_no_connect); 2992 2993 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2994 { 2995 return -EOPNOTSUPP; 2996 } 2997 EXPORT_SYMBOL(sock_no_socketpair); 2998 2999 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags, 3000 bool kern) 3001 { 3002 return -EOPNOTSUPP; 3003 } 3004 EXPORT_SYMBOL(sock_no_accept); 3005 3006 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 3007 int peer) 3008 { 3009 return -EOPNOTSUPP; 3010 } 3011 EXPORT_SYMBOL(sock_no_getname); 3012 3013 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 3014 { 3015 return -EOPNOTSUPP; 3016 } 3017 EXPORT_SYMBOL(sock_no_ioctl); 3018 3019 int sock_no_listen(struct socket *sock, int backlog) 3020 { 3021 return -EOPNOTSUPP; 3022 } 3023 EXPORT_SYMBOL(sock_no_listen); 3024 3025 int sock_no_shutdown(struct socket *sock, int how) 3026 { 3027 return -EOPNOTSUPP; 3028 } 3029 EXPORT_SYMBOL(sock_no_shutdown); 3030 3031 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 3032 { 3033 return -EOPNOTSUPP; 3034 } 3035 EXPORT_SYMBOL(sock_no_sendmsg); 3036 3037 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len) 3038 { 3039 return -EOPNOTSUPP; 3040 } 3041 EXPORT_SYMBOL(sock_no_sendmsg_locked); 3042 3043 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 3044 int flags) 3045 { 3046 return -EOPNOTSUPP; 3047 } 3048 EXPORT_SYMBOL(sock_no_recvmsg); 3049 3050 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 3051 { 3052 /* Mirror missing mmap method error code */ 3053 return -ENODEV; 3054 } 3055 EXPORT_SYMBOL(sock_no_mmap); 3056 3057 /* 3058 * When a file is received (via SCM_RIGHTS, etc), we must bump the 3059 * various sock-based usage counts. 3060 */ 3061 void __receive_sock(struct file *file) 3062 { 3063 struct socket *sock; 3064 3065 sock = sock_from_file(file); 3066 if (sock) { 3067 sock_update_netprioidx(&sock->sk->sk_cgrp_data); 3068 sock_update_classid(&sock->sk->sk_cgrp_data); 3069 } 3070 } 3071 3072 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 3073 { 3074 ssize_t res; 3075 struct msghdr msg = {.msg_flags = flags}; 3076 struct kvec iov; 3077 char *kaddr = kmap(page); 3078 iov.iov_base = kaddr + offset; 3079 iov.iov_len = size; 3080 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 3081 kunmap(page); 3082 return res; 3083 } 3084 EXPORT_SYMBOL(sock_no_sendpage); 3085 3086 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 3087 int offset, size_t size, int flags) 3088 { 3089 ssize_t res; 3090 struct msghdr msg = {.msg_flags = flags}; 3091 struct kvec iov; 3092 char *kaddr = kmap(page); 3093 3094 iov.iov_base = kaddr + offset; 3095 iov.iov_len = size; 3096 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size); 3097 kunmap(page); 3098 return res; 3099 } 3100 EXPORT_SYMBOL(sock_no_sendpage_locked); 3101 3102 /* 3103 * Default Socket Callbacks 3104 */ 3105 3106 static void sock_def_wakeup(struct sock *sk) 3107 { 3108 struct socket_wq *wq; 3109 3110 rcu_read_lock(); 3111 wq = rcu_dereference(sk->sk_wq); 3112 if (skwq_has_sleeper(wq)) 3113 wake_up_interruptible_all(&wq->wait); 3114 rcu_read_unlock(); 3115 } 3116 3117 static void sock_def_error_report(struct sock *sk) 3118 { 3119 struct socket_wq *wq; 3120 3121 rcu_read_lock(); 3122 wq = rcu_dereference(sk->sk_wq); 3123 if (skwq_has_sleeper(wq)) 3124 wake_up_interruptible_poll(&wq->wait, EPOLLERR); 3125 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 3126 rcu_read_unlock(); 3127 } 3128 3129 void sock_def_readable(struct sock *sk) 3130 { 3131 struct socket_wq *wq; 3132 3133 rcu_read_lock(); 3134 wq = rcu_dereference(sk->sk_wq); 3135 if (skwq_has_sleeper(wq)) 3136 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI | 3137 EPOLLRDNORM | EPOLLRDBAND); 3138 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 3139 rcu_read_unlock(); 3140 } 3141 3142 static void sock_def_write_space(struct sock *sk) 3143 { 3144 struct socket_wq *wq; 3145 3146 rcu_read_lock(); 3147 3148 /* Do not wake up a writer until he can make "significant" 3149 * progress. --DaveM 3150 */ 3151 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) { 3152 wq = rcu_dereference(sk->sk_wq); 3153 if (skwq_has_sleeper(wq)) 3154 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 3155 EPOLLWRNORM | EPOLLWRBAND); 3156 3157 /* Should agree with poll, otherwise some programs break */ 3158 if (sock_writeable(sk)) 3159 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 3160 } 3161 3162 rcu_read_unlock(); 3163 } 3164 3165 static void sock_def_destruct(struct sock *sk) 3166 { 3167 } 3168 3169 void sk_send_sigurg(struct sock *sk) 3170 { 3171 if (sk->sk_socket && sk->sk_socket->file) 3172 if (send_sigurg(&sk->sk_socket->file->f_owner)) 3173 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 3174 } 3175 EXPORT_SYMBOL(sk_send_sigurg); 3176 3177 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 3178 unsigned long expires) 3179 { 3180 if (!mod_timer(timer, expires)) 3181 sock_hold(sk); 3182 } 3183 EXPORT_SYMBOL(sk_reset_timer); 3184 3185 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 3186 { 3187 if (del_timer(timer)) 3188 __sock_put(sk); 3189 } 3190 EXPORT_SYMBOL(sk_stop_timer); 3191 3192 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer) 3193 { 3194 if (del_timer_sync(timer)) 3195 __sock_put(sk); 3196 } 3197 EXPORT_SYMBOL(sk_stop_timer_sync); 3198 3199 void sock_init_data(struct socket *sock, struct sock *sk) 3200 { 3201 sk_init_common(sk); 3202 sk->sk_send_head = NULL; 3203 3204 timer_setup(&sk->sk_timer, NULL, 0); 3205 3206 sk->sk_allocation = GFP_KERNEL; 3207 sk->sk_rcvbuf = sysctl_rmem_default; 3208 sk->sk_sndbuf = sysctl_wmem_default; 3209 sk->sk_state = TCP_CLOSE; 3210 sk_set_socket(sk, sock); 3211 3212 sock_set_flag(sk, SOCK_ZAPPED); 3213 3214 if (sock) { 3215 sk->sk_type = sock->type; 3216 RCU_INIT_POINTER(sk->sk_wq, &sock->wq); 3217 sock->sk = sk; 3218 sk->sk_uid = SOCK_INODE(sock)->i_uid; 3219 } else { 3220 RCU_INIT_POINTER(sk->sk_wq, NULL); 3221 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0); 3222 } 3223 3224 rwlock_init(&sk->sk_callback_lock); 3225 if (sk->sk_kern_sock) 3226 lockdep_set_class_and_name( 3227 &sk->sk_callback_lock, 3228 af_kern_callback_keys + sk->sk_family, 3229 af_family_kern_clock_key_strings[sk->sk_family]); 3230 else 3231 lockdep_set_class_and_name( 3232 &sk->sk_callback_lock, 3233 af_callback_keys + sk->sk_family, 3234 af_family_clock_key_strings[sk->sk_family]); 3235 3236 sk->sk_state_change = sock_def_wakeup; 3237 sk->sk_data_ready = sock_def_readable; 3238 sk->sk_write_space = sock_def_write_space; 3239 sk->sk_error_report = sock_def_error_report; 3240 sk->sk_destruct = sock_def_destruct; 3241 3242 sk->sk_frag.page = NULL; 3243 sk->sk_frag.offset = 0; 3244 sk->sk_peek_off = -1; 3245 3246 sk->sk_peer_pid = NULL; 3247 sk->sk_peer_cred = NULL; 3248 spin_lock_init(&sk->sk_peer_lock); 3249 3250 sk->sk_write_pending = 0; 3251 sk->sk_rcvlowat = 1; 3252 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 3253 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 3254 3255 sk->sk_stamp = SK_DEFAULT_STAMP; 3256 #if BITS_PER_LONG==32 3257 seqlock_init(&sk->sk_stamp_seq); 3258 #endif 3259 atomic_set(&sk->sk_zckey, 0); 3260 3261 #ifdef CONFIG_NET_RX_BUSY_POLL 3262 sk->sk_napi_id = 0; 3263 sk->sk_ll_usec = sysctl_net_busy_read; 3264 #endif 3265 3266 sk->sk_max_pacing_rate = ~0UL; 3267 sk->sk_pacing_rate = ~0UL; 3268 WRITE_ONCE(sk->sk_pacing_shift, 10); 3269 sk->sk_incoming_cpu = -1; 3270 3271 sk_rx_queue_clear(sk); 3272 /* 3273 * Before updating sk_refcnt, we must commit prior changes to memory 3274 * (Documentation/RCU/rculist_nulls.rst for details) 3275 */ 3276 smp_wmb(); 3277 refcount_set(&sk->sk_refcnt, 1); 3278 atomic_set(&sk->sk_drops, 0); 3279 } 3280 EXPORT_SYMBOL(sock_init_data); 3281 3282 void lock_sock_nested(struct sock *sk, int subclass) 3283 { 3284 /* The sk_lock has mutex_lock() semantics here. */ 3285 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 3286 3287 might_sleep(); 3288 spin_lock_bh(&sk->sk_lock.slock); 3289 if (sk->sk_lock.owned) 3290 __lock_sock(sk); 3291 sk->sk_lock.owned = 1; 3292 spin_unlock_bh(&sk->sk_lock.slock); 3293 } 3294 EXPORT_SYMBOL(lock_sock_nested); 3295 3296 void release_sock(struct sock *sk) 3297 { 3298 spin_lock_bh(&sk->sk_lock.slock); 3299 if (sk->sk_backlog.tail) 3300 __release_sock(sk); 3301 3302 /* Warning : release_cb() might need to release sk ownership, 3303 * ie call sock_release_ownership(sk) before us. 3304 */ 3305 if (sk->sk_prot->release_cb) 3306 sk->sk_prot->release_cb(sk); 3307 3308 sock_release_ownership(sk); 3309 if (waitqueue_active(&sk->sk_lock.wq)) 3310 wake_up(&sk->sk_lock.wq); 3311 spin_unlock_bh(&sk->sk_lock.slock); 3312 } 3313 EXPORT_SYMBOL(release_sock); 3314 3315 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock) 3316 { 3317 might_sleep(); 3318 spin_lock_bh(&sk->sk_lock.slock); 3319 3320 if (!sk->sk_lock.owned) { 3321 /* 3322 * Fast path return with bottom halves disabled and 3323 * sock::sk_lock.slock held. 3324 * 3325 * The 'mutex' is not contended and holding 3326 * sock::sk_lock.slock prevents all other lockers to 3327 * proceed so the corresponding unlock_sock_fast() can 3328 * avoid the slow path of release_sock() completely and 3329 * just release slock. 3330 * 3331 * From a semantical POV this is equivalent to 'acquiring' 3332 * the 'mutex', hence the corresponding lockdep 3333 * mutex_release() has to happen in the fast path of 3334 * unlock_sock_fast(). 3335 */ 3336 return false; 3337 } 3338 3339 __lock_sock(sk); 3340 sk->sk_lock.owned = 1; 3341 __acquire(&sk->sk_lock.slock); 3342 spin_unlock_bh(&sk->sk_lock.slock); 3343 return true; 3344 } 3345 EXPORT_SYMBOL(__lock_sock_fast); 3346 3347 int sock_gettstamp(struct socket *sock, void __user *userstamp, 3348 bool timeval, bool time32) 3349 { 3350 struct sock *sk = sock->sk; 3351 struct timespec64 ts; 3352 3353 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 3354 ts = ktime_to_timespec64(sock_read_timestamp(sk)); 3355 if (ts.tv_sec == -1) 3356 return -ENOENT; 3357 if (ts.tv_sec == 0) { 3358 ktime_t kt = ktime_get_real(); 3359 sock_write_timestamp(sk, kt); 3360 ts = ktime_to_timespec64(kt); 3361 } 3362 3363 if (timeval) 3364 ts.tv_nsec /= 1000; 3365 3366 #ifdef CONFIG_COMPAT_32BIT_TIME 3367 if (time32) 3368 return put_old_timespec32(&ts, userstamp); 3369 #endif 3370 #ifdef CONFIG_SPARC64 3371 /* beware of padding in sparc64 timeval */ 3372 if (timeval && !in_compat_syscall()) { 3373 struct __kernel_old_timeval __user tv = { 3374 .tv_sec = ts.tv_sec, 3375 .tv_usec = ts.tv_nsec, 3376 }; 3377 if (copy_to_user(userstamp, &tv, sizeof(tv))) 3378 return -EFAULT; 3379 return 0; 3380 } 3381 #endif 3382 return put_timespec64(&ts, userstamp); 3383 } 3384 EXPORT_SYMBOL(sock_gettstamp); 3385 3386 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag) 3387 { 3388 if (!sock_flag(sk, flag)) { 3389 unsigned long previous_flags = sk->sk_flags; 3390 3391 sock_set_flag(sk, flag); 3392 /* 3393 * we just set one of the two flags which require net 3394 * time stamping, but time stamping might have been on 3395 * already because of the other one 3396 */ 3397 if (sock_needs_netstamp(sk) && 3398 !(previous_flags & SK_FLAGS_TIMESTAMP)) 3399 net_enable_timestamp(); 3400 } 3401 } 3402 3403 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 3404 int level, int type) 3405 { 3406 struct sock_exterr_skb *serr; 3407 struct sk_buff *skb; 3408 int copied, err; 3409 3410 err = -EAGAIN; 3411 skb = sock_dequeue_err_skb(sk); 3412 if (skb == NULL) 3413 goto out; 3414 3415 copied = skb->len; 3416 if (copied > len) { 3417 msg->msg_flags |= MSG_TRUNC; 3418 copied = len; 3419 } 3420 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3421 if (err) 3422 goto out_free_skb; 3423 3424 sock_recv_timestamp(msg, sk, skb); 3425 3426 serr = SKB_EXT_ERR(skb); 3427 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 3428 3429 msg->msg_flags |= MSG_ERRQUEUE; 3430 err = copied; 3431 3432 out_free_skb: 3433 kfree_skb(skb); 3434 out: 3435 return err; 3436 } 3437 EXPORT_SYMBOL(sock_recv_errqueue); 3438 3439 /* 3440 * Get a socket option on an socket. 3441 * 3442 * FIX: POSIX 1003.1g is very ambiguous here. It states that 3443 * asynchronous errors should be reported by getsockopt. We assume 3444 * this means if you specify SO_ERROR (otherwise whats the point of it). 3445 */ 3446 int sock_common_getsockopt(struct socket *sock, int level, int optname, 3447 char __user *optval, int __user *optlen) 3448 { 3449 struct sock *sk = sock->sk; 3450 3451 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 3452 } 3453 EXPORT_SYMBOL(sock_common_getsockopt); 3454 3455 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 3456 int flags) 3457 { 3458 struct sock *sk = sock->sk; 3459 int addr_len = 0; 3460 int err; 3461 3462 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 3463 flags & ~MSG_DONTWAIT, &addr_len); 3464 if (err >= 0) 3465 msg->msg_namelen = addr_len; 3466 return err; 3467 } 3468 EXPORT_SYMBOL(sock_common_recvmsg); 3469 3470 /* 3471 * Set socket options on an inet socket. 3472 */ 3473 int sock_common_setsockopt(struct socket *sock, int level, int optname, 3474 sockptr_t optval, unsigned int optlen) 3475 { 3476 struct sock *sk = sock->sk; 3477 3478 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 3479 } 3480 EXPORT_SYMBOL(sock_common_setsockopt); 3481 3482 void sk_common_release(struct sock *sk) 3483 { 3484 if (sk->sk_prot->destroy) 3485 sk->sk_prot->destroy(sk); 3486 3487 /* 3488 * Observation: when sk_common_release is called, processes have 3489 * no access to socket. But net still has. 3490 * Step one, detach it from networking: 3491 * 3492 * A. Remove from hash tables. 3493 */ 3494 3495 sk->sk_prot->unhash(sk); 3496 3497 /* 3498 * In this point socket cannot receive new packets, but it is possible 3499 * that some packets are in flight because some CPU runs receiver and 3500 * did hash table lookup before we unhashed socket. They will achieve 3501 * receive queue and will be purged by socket destructor. 3502 * 3503 * Also we still have packets pending on receive queue and probably, 3504 * our own packets waiting in device queues. sock_destroy will drain 3505 * receive queue, but transmitted packets will delay socket destruction 3506 * until the last reference will be released. 3507 */ 3508 3509 sock_orphan(sk); 3510 3511 xfrm_sk_free_policy(sk); 3512 3513 sk_refcnt_debug_release(sk); 3514 3515 sock_put(sk); 3516 } 3517 EXPORT_SYMBOL(sk_common_release); 3518 3519 void sk_get_meminfo(const struct sock *sk, u32 *mem) 3520 { 3521 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); 3522 3523 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 3524 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf); 3525 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 3526 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf); 3527 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; 3528 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued); 3529 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 3530 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len); 3531 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); 3532 } 3533 3534 #ifdef CONFIG_PROC_FS 3535 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 3536 struct prot_inuse { 3537 int val[PROTO_INUSE_NR]; 3538 }; 3539 3540 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 3541 3542 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 3543 { 3544 __this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 3545 } 3546 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 3547 3548 int sock_prot_inuse_get(struct net *net, struct proto *prot) 3549 { 3550 int cpu, idx = prot->inuse_idx; 3551 int res = 0; 3552 3553 for_each_possible_cpu(cpu) 3554 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx]; 3555 3556 return res >= 0 ? res : 0; 3557 } 3558 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 3559 3560 static void sock_inuse_add(struct net *net, int val) 3561 { 3562 this_cpu_add(*net->core.sock_inuse, val); 3563 } 3564 3565 int sock_inuse_get(struct net *net) 3566 { 3567 int cpu, res = 0; 3568 3569 for_each_possible_cpu(cpu) 3570 res += *per_cpu_ptr(net->core.sock_inuse, cpu); 3571 3572 return res; 3573 } 3574 3575 EXPORT_SYMBOL_GPL(sock_inuse_get); 3576 3577 static int __net_init sock_inuse_init_net(struct net *net) 3578 { 3579 net->core.prot_inuse = alloc_percpu(struct prot_inuse); 3580 if (net->core.prot_inuse == NULL) 3581 return -ENOMEM; 3582 3583 net->core.sock_inuse = alloc_percpu(int); 3584 if (net->core.sock_inuse == NULL) 3585 goto out; 3586 3587 return 0; 3588 3589 out: 3590 free_percpu(net->core.prot_inuse); 3591 return -ENOMEM; 3592 } 3593 3594 static void __net_exit sock_inuse_exit_net(struct net *net) 3595 { 3596 free_percpu(net->core.prot_inuse); 3597 free_percpu(net->core.sock_inuse); 3598 } 3599 3600 static struct pernet_operations net_inuse_ops = { 3601 .init = sock_inuse_init_net, 3602 .exit = sock_inuse_exit_net, 3603 }; 3604 3605 static __init int net_inuse_init(void) 3606 { 3607 if (register_pernet_subsys(&net_inuse_ops)) 3608 panic("Cannot initialize net inuse counters"); 3609 3610 return 0; 3611 } 3612 3613 core_initcall(net_inuse_init); 3614 3615 static int assign_proto_idx(struct proto *prot) 3616 { 3617 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 3618 3619 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 3620 pr_err("PROTO_INUSE_NR exhausted\n"); 3621 return -ENOSPC; 3622 } 3623 3624 set_bit(prot->inuse_idx, proto_inuse_idx); 3625 return 0; 3626 } 3627 3628 static void release_proto_idx(struct proto *prot) 3629 { 3630 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 3631 clear_bit(prot->inuse_idx, proto_inuse_idx); 3632 } 3633 #else 3634 static inline int assign_proto_idx(struct proto *prot) 3635 { 3636 return 0; 3637 } 3638 3639 static inline void release_proto_idx(struct proto *prot) 3640 { 3641 } 3642 3643 static void sock_inuse_add(struct net *net, int val) 3644 { 3645 } 3646 #endif 3647 3648 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot) 3649 { 3650 if (!twsk_prot) 3651 return; 3652 kfree(twsk_prot->twsk_slab_name); 3653 twsk_prot->twsk_slab_name = NULL; 3654 kmem_cache_destroy(twsk_prot->twsk_slab); 3655 twsk_prot->twsk_slab = NULL; 3656 } 3657 3658 static int tw_prot_init(const struct proto *prot) 3659 { 3660 struct timewait_sock_ops *twsk_prot = prot->twsk_prot; 3661 3662 if (!twsk_prot) 3663 return 0; 3664 3665 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", 3666 prot->name); 3667 if (!twsk_prot->twsk_slab_name) 3668 return -ENOMEM; 3669 3670 twsk_prot->twsk_slab = 3671 kmem_cache_create(twsk_prot->twsk_slab_name, 3672 twsk_prot->twsk_obj_size, 0, 3673 SLAB_ACCOUNT | prot->slab_flags, 3674 NULL); 3675 if (!twsk_prot->twsk_slab) { 3676 pr_crit("%s: Can't create timewait sock SLAB cache!\n", 3677 prot->name); 3678 return -ENOMEM; 3679 } 3680 3681 return 0; 3682 } 3683 3684 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 3685 { 3686 if (!rsk_prot) 3687 return; 3688 kfree(rsk_prot->slab_name); 3689 rsk_prot->slab_name = NULL; 3690 kmem_cache_destroy(rsk_prot->slab); 3691 rsk_prot->slab = NULL; 3692 } 3693 3694 static int req_prot_init(const struct proto *prot) 3695 { 3696 struct request_sock_ops *rsk_prot = prot->rsk_prot; 3697 3698 if (!rsk_prot) 3699 return 0; 3700 3701 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 3702 prot->name); 3703 if (!rsk_prot->slab_name) 3704 return -ENOMEM; 3705 3706 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 3707 rsk_prot->obj_size, 0, 3708 SLAB_ACCOUNT | prot->slab_flags, 3709 NULL); 3710 3711 if (!rsk_prot->slab) { 3712 pr_crit("%s: Can't create request sock SLAB cache!\n", 3713 prot->name); 3714 return -ENOMEM; 3715 } 3716 return 0; 3717 } 3718 3719 int proto_register(struct proto *prot, int alloc_slab) 3720 { 3721 int ret = -ENOBUFS; 3722 3723 if (alloc_slab) { 3724 prot->slab = kmem_cache_create_usercopy(prot->name, 3725 prot->obj_size, 0, 3726 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | 3727 prot->slab_flags, 3728 prot->useroffset, prot->usersize, 3729 NULL); 3730 3731 if (prot->slab == NULL) { 3732 pr_crit("%s: Can't create sock SLAB cache!\n", 3733 prot->name); 3734 goto out; 3735 } 3736 3737 if (req_prot_init(prot)) 3738 goto out_free_request_sock_slab; 3739 3740 if (tw_prot_init(prot)) 3741 goto out_free_timewait_sock_slab; 3742 } 3743 3744 mutex_lock(&proto_list_mutex); 3745 ret = assign_proto_idx(prot); 3746 if (ret) { 3747 mutex_unlock(&proto_list_mutex); 3748 goto out_free_timewait_sock_slab; 3749 } 3750 list_add(&prot->node, &proto_list); 3751 mutex_unlock(&proto_list_mutex); 3752 return ret; 3753 3754 out_free_timewait_sock_slab: 3755 if (alloc_slab) 3756 tw_prot_cleanup(prot->twsk_prot); 3757 out_free_request_sock_slab: 3758 if (alloc_slab) { 3759 req_prot_cleanup(prot->rsk_prot); 3760 3761 kmem_cache_destroy(prot->slab); 3762 prot->slab = NULL; 3763 } 3764 out: 3765 return ret; 3766 } 3767 EXPORT_SYMBOL(proto_register); 3768 3769 void proto_unregister(struct proto *prot) 3770 { 3771 mutex_lock(&proto_list_mutex); 3772 release_proto_idx(prot); 3773 list_del(&prot->node); 3774 mutex_unlock(&proto_list_mutex); 3775 3776 kmem_cache_destroy(prot->slab); 3777 prot->slab = NULL; 3778 3779 req_prot_cleanup(prot->rsk_prot); 3780 tw_prot_cleanup(prot->twsk_prot); 3781 } 3782 EXPORT_SYMBOL(proto_unregister); 3783 3784 int sock_load_diag_module(int family, int protocol) 3785 { 3786 if (!protocol) { 3787 if (!sock_is_registered(family)) 3788 return -ENOENT; 3789 3790 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 3791 NETLINK_SOCK_DIAG, family); 3792 } 3793 3794 #ifdef CONFIG_INET 3795 if (family == AF_INET && 3796 protocol != IPPROTO_RAW && 3797 protocol < MAX_INET_PROTOS && 3798 !rcu_access_pointer(inet_protos[protocol])) 3799 return -ENOENT; 3800 #endif 3801 3802 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK, 3803 NETLINK_SOCK_DIAG, family, protocol); 3804 } 3805 EXPORT_SYMBOL(sock_load_diag_module); 3806 3807 #ifdef CONFIG_PROC_FS 3808 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 3809 __acquires(proto_list_mutex) 3810 { 3811 mutex_lock(&proto_list_mutex); 3812 return seq_list_start_head(&proto_list, *pos); 3813 } 3814 3815 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3816 { 3817 return seq_list_next(v, &proto_list, pos); 3818 } 3819 3820 static void proto_seq_stop(struct seq_file *seq, void *v) 3821 __releases(proto_list_mutex) 3822 { 3823 mutex_unlock(&proto_list_mutex); 3824 } 3825 3826 static char proto_method_implemented(const void *method) 3827 { 3828 return method == NULL ? 'n' : 'y'; 3829 } 3830 static long sock_prot_memory_allocated(struct proto *proto) 3831 { 3832 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 3833 } 3834 3835 static const char *sock_prot_memory_pressure(struct proto *proto) 3836 { 3837 return proto->memory_pressure != NULL ? 3838 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 3839 } 3840 3841 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 3842 { 3843 3844 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 3845 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 3846 proto->name, 3847 proto->obj_size, 3848 sock_prot_inuse_get(seq_file_net(seq), proto), 3849 sock_prot_memory_allocated(proto), 3850 sock_prot_memory_pressure(proto), 3851 proto->max_header, 3852 proto->slab == NULL ? "no" : "yes", 3853 module_name(proto->owner), 3854 proto_method_implemented(proto->close), 3855 proto_method_implemented(proto->connect), 3856 proto_method_implemented(proto->disconnect), 3857 proto_method_implemented(proto->accept), 3858 proto_method_implemented(proto->ioctl), 3859 proto_method_implemented(proto->init), 3860 proto_method_implemented(proto->destroy), 3861 proto_method_implemented(proto->shutdown), 3862 proto_method_implemented(proto->setsockopt), 3863 proto_method_implemented(proto->getsockopt), 3864 proto_method_implemented(proto->sendmsg), 3865 proto_method_implemented(proto->recvmsg), 3866 proto_method_implemented(proto->sendpage), 3867 proto_method_implemented(proto->bind), 3868 proto_method_implemented(proto->backlog_rcv), 3869 proto_method_implemented(proto->hash), 3870 proto_method_implemented(proto->unhash), 3871 proto_method_implemented(proto->get_port), 3872 proto_method_implemented(proto->enter_memory_pressure)); 3873 } 3874 3875 static int proto_seq_show(struct seq_file *seq, void *v) 3876 { 3877 if (v == &proto_list) 3878 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 3879 "protocol", 3880 "size", 3881 "sockets", 3882 "memory", 3883 "press", 3884 "maxhdr", 3885 "slab", 3886 "module", 3887 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 3888 else 3889 proto_seq_printf(seq, list_entry(v, struct proto, node)); 3890 return 0; 3891 } 3892 3893 static const struct seq_operations proto_seq_ops = { 3894 .start = proto_seq_start, 3895 .next = proto_seq_next, 3896 .stop = proto_seq_stop, 3897 .show = proto_seq_show, 3898 }; 3899 3900 static __net_init int proto_init_net(struct net *net) 3901 { 3902 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops, 3903 sizeof(struct seq_net_private))) 3904 return -ENOMEM; 3905 3906 return 0; 3907 } 3908 3909 static __net_exit void proto_exit_net(struct net *net) 3910 { 3911 remove_proc_entry("protocols", net->proc_net); 3912 } 3913 3914 3915 static __net_initdata struct pernet_operations proto_net_ops = { 3916 .init = proto_init_net, 3917 .exit = proto_exit_net, 3918 }; 3919 3920 static int __init proto_init(void) 3921 { 3922 return register_pernet_subsys(&proto_net_ops); 3923 } 3924 3925 subsys_initcall(proto_init); 3926 3927 #endif /* PROC_FS */ 3928 3929 #ifdef CONFIG_NET_RX_BUSY_POLL 3930 bool sk_busy_loop_end(void *p, unsigned long start_time) 3931 { 3932 struct sock *sk = p; 3933 3934 return !skb_queue_empty_lockless(&sk->sk_receive_queue) || 3935 sk_busy_loop_timeout(sk, start_time); 3936 } 3937 EXPORT_SYMBOL(sk_busy_loop_end); 3938 #endif /* CONFIG_NET_RX_BUSY_POLL */ 3939 3940 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len) 3941 { 3942 if (!sk->sk_prot->bind_add) 3943 return -EOPNOTSUPP; 3944 return sk->sk_prot->bind_add(sk, addr, addr_len); 3945 } 3946 EXPORT_SYMBOL(sock_bind_add); 3947