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/udp.h> 111 #include <linux/init.h> 112 #include <linux/highmem.h> 113 #include <linux/user_namespace.h> 114 #include <linux/static_key.h> 115 #include <linux/memcontrol.h> 116 #include <linux/prefetch.h> 117 #include <linux/compat.h> 118 #include <linux/mroute.h> 119 #include <linux/mroute6.h> 120 #include <linux/icmpv6.h> 121 122 #include <linux/uaccess.h> 123 124 #include <linux/netdevice.h> 125 #include <net/protocol.h> 126 #include <linux/skbuff.h> 127 #include <net/net_namespace.h> 128 #include <net/request_sock.h> 129 #include <net/sock.h> 130 #include <linux/net_tstamp.h> 131 #include <net/xfrm.h> 132 #include <linux/ipsec.h> 133 #include <net/cls_cgroup.h> 134 #include <net/netprio_cgroup.h> 135 #include <linux/sock_diag.h> 136 137 #include <linux/filter.h> 138 #include <net/sock_reuseport.h> 139 #include <net/bpf_sk_storage.h> 140 141 #include <trace/events/sock.h> 142 143 #include <net/tcp.h> 144 #include <net/busy_poll.h> 145 #include <net/phonet/phonet.h> 146 147 #include <linux/ethtool.h> 148 149 #include "dev.h" 150 151 static DEFINE_MUTEX(proto_list_mutex); 152 static LIST_HEAD(proto_list); 153 154 static void sock_def_write_space_wfree(struct sock *sk); 155 static void sock_def_write_space(struct sock *sk); 156 157 /** 158 * sk_ns_capable - General socket capability test 159 * @sk: Socket to use a capability on or through 160 * @user_ns: The user namespace of the capability to use 161 * @cap: The capability to use 162 * 163 * Test to see if the opener of the socket had when the socket was 164 * created and the current process has the capability @cap in the user 165 * namespace @user_ns. 166 */ 167 bool sk_ns_capable(const struct sock *sk, 168 struct user_namespace *user_ns, int cap) 169 { 170 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 171 ns_capable(user_ns, cap); 172 } 173 EXPORT_SYMBOL(sk_ns_capable); 174 175 /** 176 * sk_capable - Socket global capability test 177 * @sk: Socket to use a capability on or through 178 * @cap: The global capability to use 179 * 180 * Test to see if the opener of the socket had when the socket was 181 * created and the current process has the capability @cap in all user 182 * namespaces. 183 */ 184 bool sk_capable(const struct sock *sk, int cap) 185 { 186 return sk_ns_capable(sk, &init_user_ns, cap); 187 } 188 EXPORT_SYMBOL(sk_capable); 189 190 /** 191 * sk_net_capable - Network namespace socket capability test 192 * @sk: Socket to use a capability on or through 193 * @cap: The capability to use 194 * 195 * Test to see if the opener of the socket had when the socket was created 196 * and the current process has the capability @cap over the network namespace 197 * the socket is a member of. 198 */ 199 bool sk_net_capable(const struct sock *sk, int cap) 200 { 201 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 202 } 203 EXPORT_SYMBOL(sk_net_capable); 204 205 /* 206 * Each address family might have different locking rules, so we have 207 * one slock key per address family and separate keys for internal and 208 * userspace sockets. 209 */ 210 static struct lock_class_key af_family_keys[AF_MAX]; 211 static struct lock_class_key af_family_kern_keys[AF_MAX]; 212 static struct lock_class_key af_family_slock_keys[AF_MAX]; 213 static struct lock_class_key af_family_kern_slock_keys[AF_MAX]; 214 215 /* 216 * Make lock validator output more readable. (we pre-construct these 217 * strings build-time, so that runtime initialization of socket 218 * locks is fast): 219 */ 220 221 #define _sock_locks(x) \ 222 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \ 223 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \ 224 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \ 225 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \ 226 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \ 227 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \ 228 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \ 229 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \ 230 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \ 231 x "27" , x "28" , x "AF_CAN" , \ 232 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \ 233 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \ 234 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \ 235 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \ 236 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \ 237 x "AF_MCTP" , \ 238 x "AF_MAX" 239 240 static const char *const af_family_key_strings[AF_MAX+1] = { 241 _sock_locks("sk_lock-") 242 }; 243 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 244 _sock_locks("slock-") 245 }; 246 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 247 _sock_locks("clock-") 248 }; 249 250 static const char *const af_family_kern_key_strings[AF_MAX+1] = { 251 _sock_locks("k-sk_lock-") 252 }; 253 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = { 254 _sock_locks("k-slock-") 255 }; 256 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = { 257 _sock_locks("k-clock-") 258 }; 259 static const char *const af_family_rlock_key_strings[AF_MAX+1] = { 260 _sock_locks("rlock-") 261 }; 262 static const char *const af_family_wlock_key_strings[AF_MAX+1] = { 263 _sock_locks("wlock-") 264 }; 265 static const char *const af_family_elock_key_strings[AF_MAX+1] = { 266 _sock_locks("elock-") 267 }; 268 269 /* 270 * sk_callback_lock and sk queues locking rules are per-address-family, 271 * so split the lock classes by using a per-AF key: 272 */ 273 static struct lock_class_key af_callback_keys[AF_MAX]; 274 static struct lock_class_key af_rlock_keys[AF_MAX]; 275 static struct lock_class_key af_wlock_keys[AF_MAX]; 276 static struct lock_class_key af_elock_keys[AF_MAX]; 277 static struct lock_class_key af_kern_callback_keys[AF_MAX]; 278 279 /* Run time adjustable parameters. */ 280 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 281 EXPORT_SYMBOL(sysctl_wmem_max); 282 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 283 EXPORT_SYMBOL(sysctl_rmem_max); 284 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 285 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 286 287 int sysctl_tstamp_allow_data __read_mostly = 1; 288 289 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key); 290 EXPORT_SYMBOL_GPL(memalloc_socks_key); 291 292 /** 293 * sk_set_memalloc - sets %SOCK_MEMALLOC 294 * @sk: socket to set it on 295 * 296 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 297 * It's the responsibility of the admin to adjust min_free_kbytes 298 * to meet the requirements 299 */ 300 void sk_set_memalloc(struct sock *sk) 301 { 302 sock_set_flag(sk, SOCK_MEMALLOC); 303 sk->sk_allocation |= __GFP_MEMALLOC; 304 static_branch_inc(&memalloc_socks_key); 305 } 306 EXPORT_SYMBOL_GPL(sk_set_memalloc); 307 308 void sk_clear_memalloc(struct sock *sk) 309 { 310 sock_reset_flag(sk, SOCK_MEMALLOC); 311 sk->sk_allocation &= ~__GFP_MEMALLOC; 312 static_branch_dec(&memalloc_socks_key); 313 314 /* 315 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 316 * progress of swapping. SOCK_MEMALLOC may be cleared while 317 * it has rmem allocations due to the last swapfile being deactivated 318 * but there is a risk that the socket is unusable due to exceeding 319 * the rmem limits. Reclaim the reserves and obey rmem limits again. 320 */ 321 sk_mem_reclaim(sk); 322 } 323 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 324 325 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 326 { 327 int ret; 328 unsigned int noreclaim_flag; 329 330 /* these should have been dropped before queueing */ 331 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 332 333 noreclaim_flag = memalloc_noreclaim_save(); 334 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv, 335 tcp_v6_do_rcv, 336 tcp_v4_do_rcv, 337 sk, skb); 338 memalloc_noreclaim_restore(noreclaim_flag); 339 340 return ret; 341 } 342 EXPORT_SYMBOL(__sk_backlog_rcv); 343 344 void sk_error_report(struct sock *sk) 345 { 346 sk->sk_error_report(sk); 347 348 switch (sk->sk_family) { 349 case AF_INET: 350 fallthrough; 351 case AF_INET6: 352 trace_inet_sk_error_report(sk); 353 break; 354 default: 355 break; 356 } 357 } 358 EXPORT_SYMBOL(sk_error_report); 359 360 int sock_get_timeout(long timeo, void *optval, bool old_timeval) 361 { 362 struct __kernel_sock_timeval tv; 363 364 if (timeo == MAX_SCHEDULE_TIMEOUT) { 365 tv.tv_sec = 0; 366 tv.tv_usec = 0; 367 } else { 368 tv.tv_sec = timeo / HZ; 369 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ; 370 } 371 372 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 373 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec }; 374 *(struct old_timeval32 *)optval = tv32; 375 return sizeof(tv32); 376 } 377 378 if (old_timeval) { 379 struct __kernel_old_timeval old_tv; 380 old_tv.tv_sec = tv.tv_sec; 381 old_tv.tv_usec = tv.tv_usec; 382 *(struct __kernel_old_timeval *)optval = old_tv; 383 return sizeof(old_tv); 384 } 385 386 *(struct __kernel_sock_timeval *)optval = tv; 387 return sizeof(tv); 388 } 389 EXPORT_SYMBOL(sock_get_timeout); 390 391 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 392 sockptr_t optval, int optlen, bool old_timeval) 393 { 394 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 395 struct old_timeval32 tv32; 396 397 if (optlen < sizeof(tv32)) 398 return -EINVAL; 399 400 if (copy_from_sockptr(&tv32, optval, sizeof(tv32))) 401 return -EFAULT; 402 tv->tv_sec = tv32.tv_sec; 403 tv->tv_usec = tv32.tv_usec; 404 } else if (old_timeval) { 405 struct __kernel_old_timeval old_tv; 406 407 if (optlen < sizeof(old_tv)) 408 return -EINVAL; 409 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv))) 410 return -EFAULT; 411 tv->tv_sec = old_tv.tv_sec; 412 tv->tv_usec = old_tv.tv_usec; 413 } else { 414 if (optlen < sizeof(*tv)) 415 return -EINVAL; 416 if (copy_from_sockptr(tv, optval, sizeof(*tv))) 417 return -EFAULT; 418 } 419 420 return 0; 421 } 422 EXPORT_SYMBOL(sock_copy_user_timeval); 423 424 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen, 425 bool old_timeval) 426 { 427 struct __kernel_sock_timeval tv; 428 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval); 429 long val; 430 431 if (err) 432 return err; 433 434 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 435 return -EDOM; 436 437 if (tv.tv_sec < 0) { 438 static int warned __read_mostly; 439 440 WRITE_ONCE(*timeo_p, 0); 441 if (warned < 10 && net_ratelimit()) { 442 warned++; 443 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 444 __func__, current->comm, task_pid_nr(current)); 445 } 446 return 0; 447 } 448 val = MAX_SCHEDULE_TIMEOUT; 449 if ((tv.tv_sec || tv.tv_usec) && 450 (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))) 451 val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, 452 USEC_PER_SEC / HZ); 453 WRITE_ONCE(*timeo_p, val); 454 return 0; 455 } 456 457 static bool sock_needs_netstamp(const struct sock *sk) 458 { 459 switch (sk->sk_family) { 460 case AF_UNSPEC: 461 case AF_UNIX: 462 return false; 463 default: 464 return true; 465 } 466 } 467 468 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 469 { 470 if (sk->sk_flags & flags) { 471 sk->sk_flags &= ~flags; 472 if (sock_needs_netstamp(sk) && 473 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 474 net_disable_timestamp(); 475 } 476 } 477 478 479 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 480 { 481 unsigned long flags; 482 struct sk_buff_head *list = &sk->sk_receive_queue; 483 484 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 485 atomic_inc(&sk->sk_drops); 486 trace_sock_rcvqueue_full(sk, skb); 487 return -ENOMEM; 488 } 489 490 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 491 atomic_inc(&sk->sk_drops); 492 return -ENOBUFS; 493 } 494 495 skb->dev = NULL; 496 skb_set_owner_r(skb, sk); 497 498 /* we escape from rcu protected region, make sure we dont leak 499 * a norefcounted dst 500 */ 501 skb_dst_force(skb); 502 503 spin_lock_irqsave(&list->lock, flags); 504 sock_skb_set_dropcount(sk, skb); 505 __skb_queue_tail(list, skb); 506 spin_unlock_irqrestore(&list->lock, flags); 507 508 if (!sock_flag(sk, SOCK_DEAD)) 509 sk->sk_data_ready(sk); 510 return 0; 511 } 512 EXPORT_SYMBOL(__sock_queue_rcv_skb); 513 514 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 515 enum skb_drop_reason *reason) 516 { 517 enum skb_drop_reason drop_reason; 518 int err; 519 520 err = sk_filter(sk, skb); 521 if (err) { 522 drop_reason = SKB_DROP_REASON_SOCKET_FILTER; 523 goto out; 524 } 525 err = __sock_queue_rcv_skb(sk, skb); 526 switch (err) { 527 case -ENOMEM: 528 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF; 529 break; 530 case -ENOBUFS: 531 drop_reason = SKB_DROP_REASON_PROTO_MEM; 532 break; 533 default: 534 drop_reason = SKB_NOT_DROPPED_YET; 535 break; 536 } 537 out: 538 if (reason) 539 *reason = drop_reason; 540 return err; 541 } 542 EXPORT_SYMBOL(sock_queue_rcv_skb_reason); 543 544 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 545 const int nested, unsigned int trim_cap, bool refcounted) 546 { 547 int rc = NET_RX_SUCCESS; 548 549 if (sk_filter_trim_cap(sk, skb, trim_cap)) 550 goto discard_and_relse; 551 552 skb->dev = NULL; 553 554 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 555 atomic_inc(&sk->sk_drops); 556 goto discard_and_relse; 557 } 558 if (nested) 559 bh_lock_sock_nested(sk); 560 else 561 bh_lock_sock(sk); 562 if (!sock_owned_by_user(sk)) { 563 /* 564 * trylock + unlock semantics: 565 */ 566 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 567 568 rc = sk_backlog_rcv(sk, skb); 569 570 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 571 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) { 572 bh_unlock_sock(sk); 573 atomic_inc(&sk->sk_drops); 574 goto discard_and_relse; 575 } 576 577 bh_unlock_sock(sk); 578 out: 579 if (refcounted) 580 sock_put(sk); 581 return rc; 582 discard_and_relse: 583 kfree_skb(skb); 584 goto out; 585 } 586 EXPORT_SYMBOL(__sk_receive_skb); 587 588 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *, 589 u32)); 590 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *, 591 u32)); 592 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 593 { 594 struct dst_entry *dst = __sk_dst_get(sk); 595 596 if (dst && dst->obsolete && 597 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check, 598 dst, cookie) == NULL) { 599 sk_tx_queue_clear(sk); 600 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 601 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 602 dst_release(dst); 603 return NULL; 604 } 605 606 return dst; 607 } 608 EXPORT_SYMBOL(__sk_dst_check); 609 610 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 611 { 612 struct dst_entry *dst = sk_dst_get(sk); 613 614 if (dst && dst->obsolete && 615 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check, 616 dst, cookie) == NULL) { 617 sk_dst_reset(sk); 618 dst_release(dst); 619 return NULL; 620 } 621 622 return dst; 623 } 624 EXPORT_SYMBOL(sk_dst_check); 625 626 static int sock_bindtoindex_locked(struct sock *sk, int ifindex) 627 { 628 int ret = -ENOPROTOOPT; 629 #ifdef CONFIG_NETDEVICES 630 struct net *net = sock_net(sk); 631 632 /* Sorry... */ 633 ret = -EPERM; 634 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW)) 635 goto out; 636 637 ret = -EINVAL; 638 if (ifindex < 0) 639 goto out; 640 641 /* Paired with all READ_ONCE() done locklessly. */ 642 WRITE_ONCE(sk->sk_bound_dev_if, ifindex); 643 644 if (sk->sk_prot->rehash) 645 sk->sk_prot->rehash(sk); 646 sk_dst_reset(sk); 647 648 ret = 0; 649 650 out: 651 #endif 652 653 return ret; 654 } 655 656 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk) 657 { 658 int ret; 659 660 if (lock_sk) 661 lock_sock(sk); 662 ret = sock_bindtoindex_locked(sk, ifindex); 663 if (lock_sk) 664 release_sock(sk); 665 666 return ret; 667 } 668 EXPORT_SYMBOL(sock_bindtoindex); 669 670 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen) 671 { 672 int ret = -ENOPROTOOPT; 673 #ifdef CONFIG_NETDEVICES 674 struct net *net = sock_net(sk); 675 char devname[IFNAMSIZ]; 676 int index; 677 678 ret = -EINVAL; 679 if (optlen < 0) 680 goto out; 681 682 /* Bind this socket to a particular device like "eth0", 683 * as specified in the passed interface name. If the 684 * name is "" or the option length is zero the socket 685 * is not bound. 686 */ 687 if (optlen > IFNAMSIZ - 1) 688 optlen = IFNAMSIZ - 1; 689 memset(devname, 0, sizeof(devname)); 690 691 ret = -EFAULT; 692 if (copy_from_sockptr(devname, optval, optlen)) 693 goto out; 694 695 index = 0; 696 if (devname[0] != '\0') { 697 struct net_device *dev; 698 699 rcu_read_lock(); 700 dev = dev_get_by_name_rcu(net, devname); 701 if (dev) 702 index = dev->ifindex; 703 rcu_read_unlock(); 704 ret = -ENODEV; 705 if (!dev) 706 goto out; 707 } 708 709 sockopt_lock_sock(sk); 710 ret = sock_bindtoindex_locked(sk, index); 711 sockopt_release_sock(sk); 712 out: 713 #endif 714 715 return ret; 716 } 717 718 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval, 719 sockptr_t optlen, int len) 720 { 721 int ret = -ENOPROTOOPT; 722 #ifdef CONFIG_NETDEVICES 723 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 724 struct net *net = sock_net(sk); 725 char devname[IFNAMSIZ]; 726 727 if (bound_dev_if == 0) { 728 len = 0; 729 goto zero; 730 } 731 732 ret = -EINVAL; 733 if (len < IFNAMSIZ) 734 goto out; 735 736 ret = netdev_get_name(net, devname, bound_dev_if); 737 if (ret) 738 goto out; 739 740 len = strlen(devname) + 1; 741 742 ret = -EFAULT; 743 if (copy_to_sockptr(optval, devname, len)) 744 goto out; 745 746 zero: 747 ret = -EFAULT; 748 if (copy_to_sockptr(optlen, &len, sizeof(int))) 749 goto out; 750 751 ret = 0; 752 753 out: 754 #endif 755 756 return ret; 757 } 758 759 bool sk_mc_loop(const struct sock *sk) 760 { 761 if (dev_recursion_level()) 762 return false; 763 if (!sk) 764 return true; 765 /* IPV6_ADDRFORM can change sk->sk_family under us. */ 766 switch (READ_ONCE(sk->sk_family)) { 767 case AF_INET: 768 return inet_test_bit(MC_LOOP, sk); 769 #if IS_ENABLED(CONFIG_IPV6) 770 case AF_INET6: 771 return inet6_test_bit(MC6_LOOP, sk); 772 #endif 773 } 774 WARN_ON_ONCE(1); 775 return true; 776 } 777 EXPORT_SYMBOL(sk_mc_loop); 778 779 void sock_set_reuseaddr(struct sock *sk) 780 { 781 lock_sock(sk); 782 sk->sk_reuse = SK_CAN_REUSE; 783 release_sock(sk); 784 } 785 EXPORT_SYMBOL(sock_set_reuseaddr); 786 787 void sock_set_reuseport(struct sock *sk) 788 { 789 lock_sock(sk); 790 sk->sk_reuseport = true; 791 release_sock(sk); 792 } 793 EXPORT_SYMBOL(sock_set_reuseport); 794 795 void sock_no_linger(struct sock *sk) 796 { 797 lock_sock(sk); 798 WRITE_ONCE(sk->sk_lingertime, 0); 799 sock_set_flag(sk, SOCK_LINGER); 800 release_sock(sk); 801 } 802 EXPORT_SYMBOL(sock_no_linger); 803 804 void sock_set_priority(struct sock *sk, u32 priority) 805 { 806 WRITE_ONCE(sk->sk_priority, priority); 807 } 808 EXPORT_SYMBOL(sock_set_priority); 809 810 void sock_set_sndtimeo(struct sock *sk, s64 secs) 811 { 812 lock_sock(sk); 813 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1) 814 WRITE_ONCE(sk->sk_sndtimeo, secs * HZ); 815 else 816 WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT); 817 release_sock(sk); 818 } 819 EXPORT_SYMBOL(sock_set_sndtimeo); 820 821 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns) 822 { 823 if (val) { 824 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new); 825 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns); 826 sock_set_flag(sk, SOCK_RCVTSTAMP); 827 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 828 } else { 829 sock_reset_flag(sk, SOCK_RCVTSTAMP); 830 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 831 } 832 } 833 834 void sock_enable_timestamps(struct sock *sk) 835 { 836 lock_sock(sk); 837 __sock_set_timestamps(sk, true, false, true); 838 release_sock(sk); 839 } 840 EXPORT_SYMBOL(sock_enable_timestamps); 841 842 void sock_set_timestamp(struct sock *sk, int optname, bool valbool) 843 { 844 switch (optname) { 845 case SO_TIMESTAMP_OLD: 846 __sock_set_timestamps(sk, valbool, false, false); 847 break; 848 case SO_TIMESTAMP_NEW: 849 __sock_set_timestamps(sk, valbool, true, false); 850 break; 851 case SO_TIMESTAMPNS_OLD: 852 __sock_set_timestamps(sk, valbool, false, true); 853 break; 854 case SO_TIMESTAMPNS_NEW: 855 __sock_set_timestamps(sk, valbool, true, true); 856 break; 857 } 858 } 859 860 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index) 861 { 862 struct net *net = sock_net(sk); 863 struct net_device *dev = NULL; 864 bool match = false; 865 int *vclock_index; 866 int i, num; 867 868 if (sk->sk_bound_dev_if) 869 dev = dev_get_by_index(net, sk->sk_bound_dev_if); 870 871 if (!dev) { 872 pr_err("%s: sock not bind to device\n", __func__); 873 return -EOPNOTSUPP; 874 } 875 876 num = ethtool_get_phc_vclocks(dev, &vclock_index); 877 dev_put(dev); 878 879 for (i = 0; i < num; i++) { 880 if (*(vclock_index + i) == phc_index) { 881 match = true; 882 break; 883 } 884 } 885 886 if (num > 0) 887 kfree(vclock_index); 888 889 if (!match) 890 return -EINVAL; 891 892 WRITE_ONCE(sk->sk_bind_phc, phc_index); 893 894 return 0; 895 } 896 897 int sock_set_timestamping(struct sock *sk, int optname, 898 struct so_timestamping timestamping) 899 { 900 int val = timestamping.flags; 901 int ret; 902 903 if (val & ~SOF_TIMESTAMPING_MASK) 904 return -EINVAL; 905 906 if (val & SOF_TIMESTAMPING_OPT_ID_TCP && 907 !(val & SOF_TIMESTAMPING_OPT_ID)) 908 return -EINVAL; 909 910 if (val & SOF_TIMESTAMPING_OPT_ID && 911 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 912 if (sk_is_tcp(sk)) { 913 if ((1 << sk->sk_state) & 914 (TCPF_CLOSE | TCPF_LISTEN)) 915 return -EINVAL; 916 if (val & SOF_TIMESTAMPING_OPT_ID_TCP) 917 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq); 918 else 919 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una); 920 } else { 921 atomic_set(&sk->sk_tskey, 0); 922 } 923 } 924 925 if (val & SOF_TIMESTAMPING_OPT_STATS && 926 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) 927 return -EINVAL; 928 929 if (val & SOF_TIMESTAMPING_BIND_PHC) { 930 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc); 931 if (ret) 932 return ret; 933 } 934 935 WRITE_ONCE(sk->sk_tsflags, val); 936 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW); 937 938 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 939 sock_enable_timestamp(sk, 940 SOCK_TIMESTAMPING_RX_SOFTWARE); 941 else 942 sock_disable_timestamp(sk, 943 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 944 return 0; 945 } 946 947 void sock_set_keepalive(struct sock *sk) 948 { 949 lock_sock(sk); 950 if (sk->sk_prot->keepalive) 951 sk->sk_prot->keepalive(sk, true); 952 sock_valbool_flag(sk, SOCK_KEEPOPEN, true); 953 release_sock(sk); 954 } 955 EXPORT_SYMBOL(sock_set_keepalive); 956 957 static void __sock_set_rcvbuf(struct sock *sk, int val) 958 { 959 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it 960 * as a negative value. 961 */ 962 val = min_t(int, val, INT_MAX / 2); 963 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 964 965 /* We double it on the way in to account for "struct sk_buff" etc. 966 * overhead. Applications assume that the SO_RCVBUF setting they make 967 * will allow that much actual data to be received on that socket. 968 * 969 * Applications are unaware that "struct sk_buff" and other overheads 970 * allocate from the receive buffer during socket buffer allocation. 971 * 972 * And after considering the possible alternatives, returning the value 973 * we actually used in getsockopt is the most desirable behavior. 974 */ 975 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF)); 976 } 977 978 void sock_set_rcvbuf(struct sock *sk, int val) 979 { 980 lock_sock(sk); 981 __sock_set_rcvbuf(sk, val); 982 release_sock(sk); 983 } 984 EXPORT_SYMBOL(sock_set_rcvbuf); 985 986 static void __sock_set_mark(struct sock *sk, u32 val) 987 { 988 if (val != sk->sk_mark) { 989 WRITE_ONCE(sk->sk_mark, val); 990 sk_dst_reset(sk); 991 } 992 } 993 994 void sock_set_mark(struct sock *sk, u32 val) 995 { 996 lock_sock(sk); 997 __sock_set_mark(sk, val); 998 release_sock(sk); 999 } 1000 EXPORT_SYMBOL(sock_set_mark); 1001 1002 static void sock_release_reserved_memory(struct sock *sk, int bytes) 1003 { 1004 /* Round down bytes to multiple of pages */ 1005 bytes = round_down(bytes, PAGE_SIZE); 1006 1007 WARN_ON(bytes > sk->sk_reserved_mem); 1008 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes); 1009 sk_mem_reclaim(sk); 1010 } 1011 1012 static int sock_reserve_memory(struct sock *sk, int bytes) 1013 { 1014 long allocated; 1015 bool charged; 1016 int pages; 1017 1018 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk)) 1019 return -EOPNOTSUPP; 1020 1021 if (!bytes) 1022 return 0; 1023 1024 pages = sk_mem_pages(bytes); 1025 1026 /* pre-charge to memcg */ 1027 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages, 1028 GFP_KERNEL | __GFP_RETRY_MAYFAIL); 1029 if (!charged) 1030 return -ENOMEM; 1031 1032 /* pre-charge to forward_alloc */ 1033 sk_memory_allocated_add(sk, pages); 1034 allocated = sk_memory_allocated(sk); 1035 /* If the system goes into memory pressure with this 1036 * precharge, give up and return error. 1037 */ 1038 if (allocated > sk_prot_mem_limits(sk, 1)) { 1039 sk_memory_allocated_sub(sk, pages); 1040 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages); 1041 return -ENOMEM; 1042 } 1043 sk_forward_alloc_add(sk, pages << PAGE_SHIFT); 1044 1045 WRITE_ONCE(sk->sk_reserved_mem, 1046 sk->sk_reserved_mem + (pages << PAGE_SHIFT)); 1047 1048 return 0; 1049 } 1050 1051 void sockopt_lock_sock(struct sock *sk) 1052 { 1053 /* When current->bpf_ctx is set, the setsockopt is called from 1054 * a bpf prog. bpf has ensured the sk lock has been 1055 * acquired before calling setsockopt(). 1056 */ 1057 if (has_current_bpf_ctx()) 1058 return; 1059 1060 lock_sock(sk); 1061 } 1062 EXPORT_SYMBOL(sockopt_lock_sock); 1063 1064 void sockopt_release_sock(struct sock *sk) 1065 { 1066 if (has_current_bpf_ctx()) 1067 return; 1068 1069 release_sock(sk); 1070 } 1071 EXPORT_SYMBOL(sockopt_release_sock); 1072 1073 bool sockopt_ns_capable(struct user_namespace *ns, int cap) 1074 { 1075 return has_current_bpf_ctx() || ns_capable(ns, cap); 1076 } 1077 EXPORT_SYMBOL(sockopt_ns_capable); 1078 1079 bool sockopt_capable(int cap) 1080 { 1081 return has_current_bpf_ctx() || capable(cap); 1082 } 1083 EXPORT_SYMBOL(sockopt_capable); 1084 1085 /* 1086 * This is meant for all protocols to use and covers goings on 1087 * at the socket level. Everything here is generic. 1088 */ 1089 1090 int sk_setsockopt(struct sock *sk, int level, int optname, 1091 sockptr_t optval, unsigned int optlen) 1092 { 1093 struct so_timestamping timestamping; 1094 struct socket *sock = sk->sk_socket; 1095 struct sock_txtime sk_txtime; 1096 int val; 1097 int valbool; 1098 struct linger ling; 1099 int ret = 0; 1100 1101 /* 1102 * Options without arguments 1103 */ 1104 1105 if (optname == SO_BINDTODEVICE) 1106 return sock_setbindtodevice(sk, optval, optlen); 1107 1108 if (optlen < sizeof(int)) 1109 return -EINVAL; 1110 1111 if (copy_from_sockptr(&val, optval, sizeof(val))) 1112 return -EFAULT; 1113 1114 valbool = val ? 1 : 0; 1115 1116 /* handle options which do not require locking the socket. */ 1117 switch (optname) { 1118 case SO_PRIORITY: 1119 if ((val >= 0 && val <= 6) || 1120 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) || 1121 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1122 sock_set_priority(sk, val); 1123 return 0; 1124 } 1125 return -EPERM; 1126 case SO_PASSSEC: 1127 assign_bit(SOCK_PASSSEC, &sock->flags, valbool); 1128 return 0; 1129 case SO_PASSCRED: 1130 assign_bit(SOCK_PASSCRED, &sock->flags, valbool); 1131 return 0; 1132 case SO_PASSPIDFD: 1133 assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool); 1134 return 0; 1135 case SO_TYPE: 1136 case SO_PROTOCOL: 1137 case SO_DOMAIN: 1138 case SO_ERROR: 1139 return -ENOPROTOOPT; 1140 #ifdef CONFIG_NET_RX_BUSY_POLL 1141 case SO_BUSY_POLL: 1142 if (val < 0) 1143 return -EINVAL; 1144 WRITE_ONCE(sk->sk_ll_usec, val); 1145 return 0; 1146 case SO_PREFER_BUSY_POLL: 1147 if (valbool && !sockopt_capable(CAP_NET_ADMIN)) 1148 return -EPERM; 1149 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool); 1150 return 0; 1151 case SO_BUSY_POLL_BUDGET: 1152 if (val > READ_ONCE(sk->sk_busy_poll_budget) && 1153 !sockopt_capable(CAP_NET_ADMIN)) 1154 return -EPERM; 1155 if (val < 0 || val > U16_MAX) 1156 return -EINVAL; 1157 WRITE_ONCE(sk->sk_busy_poll_budget, val); 1158 return 0; 1159 #endif 1160 case SO_MAX_PACING_RATE: 1161 { 1162 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val; 1163 unsigned long pacing_rate; 1164 1165 if (sizeof(ulval) != sizeof(val) && 1166 optlen >= sizeof(ulval) && 1167 copy_from_sockptr(&ulval, optval, sizeof(ulval))) { 1168 return -EFAULT; 1169 } 1170 if (ulval != ~0UL) 1171 cmpxchg(&sk->sk_pacing_status, 1172 SK_PACING_NONE, 1173 SK_PACING_NEEDED); 1174 /* Pairs with READ_ONCE() from sk_getsockopt() */ 1175 WRITE_ONCE(sk->sk_max_pacing_rate, ulval); 1176 pacing_rate = READ_ONCE(sk->sk_pacing_rate); 1177 if (ulval < pacing_rate) 1178 WRITE_ONCE(sk->sk_pacing_rate, ulval); 1179 return 0; 1180 } 1181 case SO_TXREHASH: 1182 if (val < -1 || val > 1) 1183 return -EINVAL; 1184 if ((u8)val == SOCK_TXREHASH_DEFAULT) 1185 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash); 1186 /* Paired with READ_ONCE() in tcp_rtx_synack() 1187 * and sk_getsockopt(). 1188 */ 1189 WRITE_ONCE(sk->sk_txrehash, (u8)val); 1190 return 0; 1191 case SO_PEEK_OFF: 1192 { 1193 int (*set_peek_off)(struct sock *sk, int val); 1194 1195 set_peek_off = READ_ONCE(sock->ops)->set_peek_off; 1196 if (set_peek_off) 1197 ret = set_peek_off(sk, val); 1198 else 1199 ret = -EOPNOTSUPP; 1200 return ret; 1201 } 1202 } 1203 1204 sockopt_lock_sock(sk); 1205 1206 switch (optname) { 1207 case SO_DEBUG: 1208 if (val && !sockopt_capable(CAP_NET_ADMIN)) 1209 ret = -EACCES; 1210 else 1211 sock_valbool_flag(sk, SOCK_DBG, valbool); 1212 break; 1213 case SO_REUSEADDR: 1214 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 1215 break; 1216 case SO_REUSEPORT: 1217 sk->sk_reuseport = valbool; 1218 break; 1219 case SO_DONTROUTE: 1220 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 1221 sk_dst_reset(sk); 1222 break; 1223 case SO_BROADCAST: 1224 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 1225 break; 1226 case SO_SNDBUF: 1227 /* Don't error on this BSD doesn't and if you think 1228 * about it this is right. Otherwise apps have to 1229 * play 'guess the biggest size' games. RCVBUF/SNDBUF 1230 * are treated in BSD as hints 1231 */ 1232 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max)); 1233 set_sndbuf: 1234 /* Ensure val * 2 fits into an int, to prevent max_t() 1235 * from treating it as a negative value. 1236 */ 1237 val = min_t(int, val, INT_MAX / 2); 1238 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 1239 WRITE_ONCE(sk->sk_sndbuf, 1240 max_t(int, val * 2, SOCK_MIN_SNDBUF)); 1241 /* Wake up sending tasks if we upped the value. */ 1242 sk->sk_write_space(sk); 1243 break; 1244 1245 case SO_SNDBUFFORCE: 1246 if (!sockopt_capable(CAP_NET_ADMIN)) { 1247 ret = -EPERM; 1248 break; 1249 } 1250 1251 /* No negative values (to prevent underflow, as val will be 1252 * multiplied by 2). 1253 */ 1254 if (val < 0) 1255 val = 0; 1256 goto set_sndbuf; 1257 1258 case SO_RCVBUF: 1259 /* Don't error on this BSD doesn't and if you think 1260 * about it this is right. Otherwise apps have to 1261 * play 'guess the biggest size' games. RCVBUF/SNDBUF 1262 * are treated in BSD as hints 1263 */ 1264 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max))); 1265 break; 1266 1267 case SO_RCVBUFFORCE: 1268 if (!sockopt_capable(CAP_NET_ADMIN)) { 1269 ret = -EPERM; 1270 break; 1271 } 1272 1273 /* No negative values (to prevent underflow, as val will be 1274 * multiplied by 2). 1275 */ 1276 __sock_set_rcvbuf(sk, max(val, 0)); 1277 break; 1278 1279 case SO_KEEPALIVE: 1280 if (sk->sk_prot->keepalive) 1281 sk->sk_prot->keepalive(sk, valbool); 1282 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 1283 break; 1284 1285 case SO_OOBINLINE: 1286 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 1287 break; 1288 1289 case SO_NO_CHECK: 1290 sk->sk_no_check_tx = valbool; 1291 break; 1292 1293 case SO_LINGER: 1294 if (optlen < sizeof(ling)) { 1295 ret = -EINVAL; /* 1003.1g */ 1296 break; 1297 } 1298 if (copy_from_sockptr(&ling, optval, sizeof(ling))) { 1299 ret = -EFAULT; 1300 break; 1301 } 1302 if (!ling.l_onoff) { 1303 sock_reset_flag(sk, SOCK_LINGER); 1304 } else { 1305 unsigned long t_sec = ling.l_linger; 1306 1307 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ) 1308 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT); 1309 else 1310 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ); 1311 sock_set_flag(sk, SOCK_LINGER); 1312 } 1313 break; 1314 1315 case SO_BSDCOMPAT: 1316 break; 1317 1318 case SO_TIMESTAMP_OLD: 1319 case SO_TIMESTAMP_NEW: 1320 case SO_TIMESTAMPNS_OLD: 1321 case SO_TIMESTAMPNS_NEW: 1322 sock_set_timestamp(sk, optname, valbool); 1323 break; 1324 1325 case SO_TIMESTAMPING_NEW: 1326 case SO_TIMESTAMPING_OLD: 1327 if (optlen == sizeof(timestamping)) { 1328 if (copy_from_sockptr(×tamping, optval, 1329 sizeof(timestamping))) { 1330 ret = -EFAULT; 1331 break; 1332 } 1333 } else { 1334 memset(×tamping, 0, sizeof(timestamping)); 1335 timestamping.flags = val; 1336 } 1337 ret = sock_set_timestamping(sk, optname, timestamping); 1338 break; 1339 1340 case SO_RCVLOWAT: 1341 { 1342 int (*set_rcvlowat)(struct sock *sk, int val) = NULL; 1343 1344 if (val < 0) 1345 val = INT_MAX; 1346 if (sock) 1347 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat; 1348 if (set_rcvlowat) 1349 ret = set_rcvlowat(sk, val); 1350 else 1351 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 1352 break; 1353 } 1354 case SO_RCVTIMEO_OLD: 1355 case SO_RCVTIMEO_NEW: 1356 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, 1357 optlen, optname == SO_RCVTIMEO_OLD); 1358 break; 1359 1360 case SO_SNDTIMEO_OLD: 1361 case SO_SNDTIMEO_NEW: 1362 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, 1363 optlen, optname == SO_SNDTIMEO_OLD); 1364 break; 1365 1366 case SO_ATTACH_FILTER: { 1367 struct sock_fprog fprog; 1368 1369 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); 1370 if (!ret) 1371 ret = sk_attach_filter(&fprog, sk); 1372 break; 1373 } 1374 case SO_ATTACH_BPF: 1375 ret = -EINVAL; 1376 if (optlen == sizeof(u32)) { 1377 u32 ufd; 1378 1379 ret = -EFAULT; 1380 if (copy_from_sockptr(&ufd, optval, sizeof(ufd))) 1381 break; 1382 1383 ret = sk_attach_bpf(ufd, sk); 1384 } 1385 break; 1386 1387 case SO_ATTACH_REUSEPORT_CBPF: { 1388 struct sock_fprog fprog; 1389 1390 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); 1391 if (!ret) 1392 ret = sk_reuseport_attach_filter(&fprog, sk); 1393 break; 1394 } 1395 case SO_ATTACH_REUSEPORT_EBPF: 1396 ret = -EINVAL; 1397 if (optlen == sizeof(u32)) { 1398 u32 ufd; 1399 1400 ret = -EFAULT; 1401 if (copy_from_sockptr(&ufd, optval, sizeof(ufd))) 1402 break; 1403 1404 ret = sk_reuseport_attach_bpf(ufd, sk); 1405 } 1406 break; 1407 1408 case SO_DETACH_REUSEPORT_BPF: 1409 ret = reuseport_detach_prog(sk); 1410 break; 1411 1412 case SO_DETACH_FILTER: 1413 ret = sk_detach_filter(sk); 1414 break; 1415 1416 case SO_LOCK_FILTER: 1417 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 1418 ret = -EPERM; 1419 else 1420 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 1421 break; 1422 1423 case SO_MARK: 1424 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && 1425 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1426 ret = -EPERM; 1427 break; 1428 } 1429 1430 __sock_set_mark(sk, val); 1431 break; 1432 case SO_RCVMARK: 1433 sock_valbool_flag(sk, SOCK_RCVMARK, valbool); 1434 break; 1435 1436 case SO_RXQ_OVFL: 1437 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 1438 break; 1439 1440 case SO_WIFI_STATUS: 1441 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 1442 break; 1443 1444 case SO_NOFCS: 1445 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 1446 break; 1447 1448 case SO_SELECT_ERR_QUEUE: 1449 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 1450 break; 1451 1452 1453 case SO_INCOMING_CPU: 1454 reuseport_update_incoming_cpu(sk, val); 1455 break; 1456 1457 case SO_CNX_ADVICE: 1458 if (val == 1) 1459 dst_negative_advice(sk); 1460 break; 1461 1462 case SO_ZEROCOPY: 1463 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) { 1464 if (!(sk_is_tcp(sk) || 1465 (sk->sk_type == SOCK_DGRAM && 1466 sk->sk_protocol == IPPROTO_UDP))) 1467 ret = -EOPNOTSUPP; 1468 } else if (sk->sk_family != PF_RDS) { 1469 ret = -EOPNOTSUPP; 1470 } 1471 if (!ret) { 1472 if (val < 0 || val > 1) 1473 ret = -EINVAL; 1474 else 1475 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); 1476 } 1477 break; 1478 1479 case SO_TXTIME: 1480 if (optlen != sizeof(struct sock_txtime)) { 1481 ret = -EINVAL; 1482 break; 1483 } else if (copy_from_sockptr(&sk_txtime, optval, 1484 sizeof(struct sock_txtime))) { 1485 ret = -EFAULT; 1486 break; 1487 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) { 1488 ret = -EINVAL; 1489 break; 1490 } 1491 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet 1492 * scheduler has enough safe guards. 1493 */ 1494 if (sk_txtime.clockid != CLOCK_MONOTONIC && 1495 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1496 ret = -EPERM; 1497 break; 1498 } 1499 sock_valbool_flag(sk, SOCK_TXTIME, true); 1500 sk->sk_clockid = sk_txtime.clockid; 1501 sk->sk_txtime_deadline_mode = 1502 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE); 1503 sk->sk_txtime_report_errors = 1504 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS); 1505 break; 1506 1507 case SO_BINDTOIFINDEX: 1508 ret = sock_bindtoindex_locked(sk, val); 1509 break; 1510 1511 case SO_BUF_LOCK: 1512 if (val & ~SOCK_BUF_LOCK_MASK) { 1513 ret = -EINVAL; 1514 break; 1515 } 1516 sk->sk_userlocks = val | (sk->sk_userlocks & 1517 ~SOCK_BUF_LOCK_MASK); 1518 break; 1519 1520 case SO_RESERVE_MEM: 1521 { 1522 int delta; 1523 1524 if (val < 0) { 1525 ret = -EINVAL; 1526 break; 1527 } 1528 1529 delta = val - sk->sk_reserved_mem; 1530 if (delta < 0) 1531 sock_release_reserved_memory(sk, -delta); 1532 else 1533 ret = sock_reserve_memory(sk, delta); 1534 break; 1535 } 1536 1537 default: 1538 ret = -ENOPROTOOPT; 1539 break; 1540 } 1541 sockopt_release_sock(sk); 1542 return ret; 1543 } 1544 1545 int sock_setsockopt(struct socket *sock, int level, int optname, 1546 sockptr_t optval, unsigned int optlen) 1547 { 1548 return sk_setsockopt(sock->sk, level, optname, 1549 optval, optlen); 1550 } 1551 EXPORT_SYMBOL(sock_setsockopt); 1552 1553 static const struct cred *sk_get_peer_cred(struct sock *sk) 1554 { 1555 const struct cred *cred; 1556 1557 spin_lock(&sk->sk_peer_lock); 1558 cred = get_cred(sk->sk_peer_cred); 1559 spin_unlock(&sk->sk_peer_lock); 1560 1561 return cred; 1562 } 1563 1564 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1565 struct ucred *ucred) 1566 { 1567 ucred->pid = pid_vnr(pid); 1568 ucred->uid = ucred->gid = -1; 1569 if (cred) { 1570 struct user_namespace *current_ns = current_user_ns(); 1571 1572 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1573 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1574 } 1575 } 1576 1577 static int groups_to_user(sockptr_t dst, const struct group_info *src) 1578 { 1579 struct user_namespace *user_ns = current_user_ns(); 1580 int i; 1581 1582 for (i = 0; i < src->ngroups; i++) { 1583 gid_t gid = from_kgid_munged(user_ns, src->gid[i]); 1584 1585 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid))) 1586 return -EFAULT; 1587 } 1588 1589 return 0; 1590 } 1591 1592 int sk_getsockopt(struct sock *sk, int level, int optname, 1593 sockptr_t optval, sockptr_t optlen) 1594 { 1595 struct socket *sock = sk->sk_socket; 1596 1597 union { 1598 int val; 1599 u64 val64; 1600 unsigned long ulval; 1601 struct linger ling; 1602 struct old_timeval32 tm32; 1603 struct __kernel_old_timeval tm; 1604 struct __kernel_sock_timeval stm; 1605 struct sock_txtime txtime; 1606 struct so_timestamping timestamping; 1607 } v; 1608 1609 int lv = sizeof(int); 1610 int len; 1611 1612 if (copy_from_sockptr(&len, optlen, sizeof(int))) 1613 return -EFAULT; 1614 if (len < 0) 1615 return -EINVAL; 1616 1617 memset(&v, 0, sizeof(v)); 1618 1619 switch (optname) { 1620 case SO_DEBUG: 1621 v.val = sock_flag(sk, SOCK_DBG); 1622 break; 1623 1624 case SO_DONTROUTE: 1625 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1626 break; 1627 1628 case SO_BROADCAST: 1629 v.val = sock_flag(sk, SOCK_BROADCAST); 1630 break; 1631 1632 case SO_SNDBUF: 1633 v.val = READ_ONCE(sk->sk_sndbuf); 1634 break; 1635 1636 case SO_RCVBUF: 1637 v.val = READ_ONCE(sk->sk_rcvbuf); 1638 break; 1639 1640 case SO_REUSEADDR: 1641 v.val = sk->sk_reuse; 1642 break; 1643 1644 case SO_REUSEPORT: 1645 v.val = sk->sk_reuseport; 1646 break; 1647 1648 case SO_KEEPALIVE: 1649 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1650 break; 1651 1652 case SO_TYPE: 1653 v.val = sk->sk_type; 1654 break; 1655 1656 case SO_PROTOCOL: 1657 v.val = sk->sk_protocol; 1658 break; 1659 1660 case SO_DOMAIN: 1661 v.val = sk->sk_family; 1662 break; 1663 1664 case SO_ERROR: 1665 v.val = -sock_error(sk); 1666 if (v.val == 0) 1667 v.val = xchg(&sk->sk_err_soft, 0); 1668 break; 1669 1670 case SO_OOBINLINE: 1671 v.val = sock_flag(sk, SOCK_URGINLINE); 1672 break; 1673 1674 case SO_NO_CHECK: 1675 v.val = sk->sk_no_check_tx; 1676 break; 1677 1678 case SO_PRIORITY: 1679 v.val = READ_ONCE(sk->sk_priority); 1680 break; 1681 1682 case SO_LINGER: 1683 lv = sizeof(v.ling); 1684 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1685 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ; 1686 break; 1687 1688 case SO_BSDCOMPAT: 1689 break; 1690 1691 case SO_TIMESTAMP_OLD: 1692 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1693 !sock_flag(sk, SOCK_TSTAMP_NEW) && 1694 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1695 break; 1696 1697 case SO_TIMESTAMPNS_OLD: 1698 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW); 1699 break; 1700 1701 case SO_TIMESTAMP_NEW: 1702 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW); 1703 break; 1704 1705 case SO_TIMESTAMPNS_NEW: 1706 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW); 1707 break; 1708 1709 case SO_TIMESTAMPING_OLD: 1710 case SO_TIMESTAMPING_NEW: 1711 lv = sizeof(v.timestamping); 1712 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only 1713 * returning the flags when they were set through the same option. 1714 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD. 1715 */ 1716 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) { 1717 v.timestamping.flags = READ_ONCE(sk->sk_tsflags); 1718 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc); 1719 } 1720 break; 1721 1722 case SO_RCVTIMEO_OLD: 1723 case SO_RCVTIMEO_NEW: 1724 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v, 1725 SO_RCVTIMEO_OLD == optname); 1726 break; 1727 1728 case SO_SNDTIMEO_OLD: 1729 case SO_SNDTIMEO_NEW: 1730 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v, 1731 SO_SNDTIMEO_OLD == optname); 1732 break; 1733 1734 case SO_RCVLOWAT: 1735 v.val = READ_ONCE(sk->sk_rcvlowat); 1736 break; 1737 1738 case SO_SNDLOWAT: 1739 v.val = 1; 1740 break; 1741 1742 case SO_PASSCRED: 1743 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1744 break; 1745 1746 case SO_PASSPIDFD: 1747 v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags); 1748 break; 1749 1750 case SO_PEERCRED: 1751 { 1752 struct ucred peercred; 1753 if (len > sizeof(peercred)) 1754 len = sizeof(peercred); 1755 1756 spin_lock(&sk->sk_peer_lock); 1757 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1758 spin_unlock(&sk->sk_peer_lock); 1759 1760 if (copy_to_sockptr(optval, &peercred, len)) 1761 return -EFAULT; 1762 goto lenout; 1763 } 1764 1765 case SO_PEERPIDFD: 1766 { 1767 struct pid *peer_pid; 1768 struct file *pidfd_file = NULL; 1769 int pidfd; 1770 1771 if (len > sizeof(pidfd)) 1772 len = sizeof(pidfd); 1773 1774 spin_lock(&sk->sk_peer_lock); 1775 peer_pid = get_pid(sk->sk_peer_pid); 1776 spin_unlock(&sk->sk_peer_lock); 1777 1778 if (!peer_pid) 1779 return -ENODATA; 1780 1781 pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file); 1782 put_pid(peer_pid); 1783 if (pidfd < 0) 1784 return pidfd; 1785 1786 if (copy_to_sockptr(optval, &pidfd, len) || 1787 copy_to_sockptr(optlen, &len, sizeof(int))) { 1788 put_unused_fd(pidfd); 1789 fput(pidfd_file); 1790 1791 return -EFAULT; 1792 } 1793 1794 fd_install(pidfd, pidfd_file); 1795 return 0; 1796 } 1797 1798 case SO_PEERGROUPS: 1799 { 1800 const struct cred *cred; 1801 int ret, n; 1802 1803 cred = sk_get_peer_cred(sk); 1804 if (!cred) 1805 return -ENODATA; 1806 1807 n = cred->group_info->ngroups; 1808 if (len < n * sizeof(gid_t)) { 1809 len = n * sizeof(gid_t); 1810 put_cred(cred); 1811 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE; 1812 } 1813 len = n * sizeof(gid_t); 1814 1815 ret = groups_to_user(optval, cred->group_info); 1816 put_cred(cred); 1817 if (ret) 1818 return ret; 1819 goto lenout; 1820 } 1821 1822 case SO_PEERNAME: 1823 { 1824 struct sockaddr_storage address; 1825 1826 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2); 1827 if (lv < 0) 1828 return -ENOTCONN; 1829 if (lv < len) 1830 return -EINVAL; 1831 if (copy_to_sockptr(optval, &address, len)) 1832 return -EFAULT; 1833 goto lenout; 1834 } 1835 1836 /* Dubious BSD thing... Probably nobody even uses it, but 1837 * the UNIX standard wants it for whatever reason... -DaveM 1838 */ 1839 case SO_ACCEPTCONN: 1840 v.val = sk->sk_state == TCP_LISTEN; 1841 break; 1842 1843 case SO_PASSSEC: 1844 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1845 break; 1846 1847 case SO_PEERSEC: 1848 return security_socket_getpeersec_stream(sock, 1849 optval, optlen, len); 1850 1851 case SO_MARK: 1852 v.val = READ_ONCE(sk->sk_mark); 1853 break; 1854 1855 case SO_RCVMARK: 1856 v.val = sock_flag(sk, SOCK_RCVMARK); 1857 break; 1858 1859 case SO_RXQ_OVFL: 1860 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1861 break; 1862 1863 case SO_WIFI_STATUS: 1864 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1865 break; 1866 1867 case SO_PEEK_OFF: 1868 if (!READ_ONCE(sock->ops)->set_peek_off) 1869 return -EOPNOTSUPP; 1870 1871 v.val = READ_ONCE(sk->sk_peek_off); 1872 break; 1873 case SO_NOFCS: 1874 v.val = sock_flag(sk, SOCK_NOFCS); 1875 break; 1876 1877 case SO_BINDTODEVICE: 1878 return sock_getbindtodevice(sk, optval, optlen, len); 1879 1880 case SO_GET_FILTER: 1881 len = sk_get_filter(sk, optval, len); 1882 if (len < 0) 1883 return len; 1884 1885 goto lenout; 1886 1887 case SO_LOCK_FILTER: 1888 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1889 break; 1890 1891 case SO_BPF_EXTENSIONS: 1892 v.val = bpf_tell_extensions(); 1893 break; 1894 1895 case SO_SELECT_ERR_QUEUE: 1896 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1897 break; 1898 1899 #ifdef CONFIG_NET_RX_BUSY_POLL 1900 case SO_BUSY_POLL: 1901 v.val = READ_ONCE(sk->sk_ll_usec); 1902 break; 1903 case SO_PREFER_BUSY_POLL: 1904 v.val = READ_ONCE(sk->sk_prefer_busy_poll); 1905 break; 1906 #endif 1907 1908 case SO_MAX_PACING_RATE: 1909 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */ 1910 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) { 1911 lv = sizeof(v.ulval); 1912 v.ulval = READ_ONCE(sk->sk_max_pacing_rate); 1913 } else { 1914 /* 32bit version */ 1915 v.val = min_t(unsigned long, ~0U, 1916 READ_ONCE(sk->sk_max_pacing_rate)); 1917 } 1918 break; 1919 1920 case SO_INCOMING_CPU: 1921 v.val = READ_ONCE(sk->sk_incoming_cpu); 1922 break; 1923 1924 case SO_MEMINFO: 1925 { 1926 u32 meminfo[SK_MEMINFO_VARS]; 1927 1928 sk_get_meminfo(sk, meminfo); 1929 1930 len = min_t(unsigned int, len, sizeof(meminfo)); 1931 if (copy_to_sockptr(optval, &meminfo, len)) 1932 return -EFAULT; 1933 1934 goto lenout; 1935 } 1936 1937 #ifdef CONFIG_NET_RX_BUSY_POLL 1938 case SO_INCOMING_NAPI_ID: 1939 v.val = READ_ONCE(sk->sk_napi_id); 1940 1941 /* aggregate non-NAPI IDs down to 0 */ 1942 if (v.val < MIN_NAPI_ID) 1943 v.val = 0; 1944 1945 break; 1946 #endif 1947 1948 case SO_COOKIE: 1949 lv = sizeof(u64); 1950 if (len < lv) 1951 return -EINVAL; 1952 v.val64 = sock_gen_cookie(sk); 1953 break; 1954 1955 case SO_ZEROCOPY: 1956 v.val = sock_flag(sk, SOCK_ZEROCOPY); 1957 break; 1958 1959 case SO_TXTIME: 1960 lv = sizeof(v.txtime); 1961 v.txtime.clockid = sk->sk_clockid; 1962 v.txtime.flags |= sk->sk_txtime_deadline_mode ? 1963 SOF_TXTIME_DEADLINE_MODE : 0; 1964 v.txtime.flags |= sk->sk_txtime_report_errors ? 1965 SOF_TXTIME_REPORT_ERRORS : 0; 1966 break; 1967 1968 case SO_BINDTOIFINDEX: 1969 v.val = READ_ONCE(sk->sk_bound_dev_if); 1970 break; 1971 1972 case SO_NETNS_COOKIE: 1973 lv = sizeof(u64); 1974 if (len != lv) 1975 return -EINVAL; 1976 v.val64 = sock_net(sk)->net_cookie; 1977 break; 1978 1979 case SO_BUF_LOCK: 1980 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK; 1981 break; 1982 1983 case SO_RESERVE_MEM: 1984 v.val = READ_ONCE(sk->sk_reserved_mem); 1985 break; 1986 1987 case SO_TXREHASH: 1988 /* Paired with WRITE_ONCE() in sk_setsockopt() */ 1989 v.val = READ_ONCE(sk->sk_txrehash); 1990 break; 1991 1992 default: 1993 /* We implement the SO_SNDLOWAT etc to not be settable 1994 * (1003.1g 7). 1995 */ 1996 return -ENOPROTOOPT; 1997 } 1998 1999 if (len > lv) 2000 len = lv; 2001 if (copy_to_sockptr(optval, &v, len)) 2002 return -EFAULT; 2003 lenout: 2004 if (copy_to_sockptr(optlen, &len, sizeof(int))) 2005 return -EFAULT; 2006 return 0; 2007 } 2008 2009 /* 2010 * Initialize an sk_lock. 2011 * 2012 * (We also register the sk_lock with the lock validator.) 2013 */ 2014 static inline void sock_lock_init(struct sock *sk) 2015 { 2016 if (sk->sk_kern_sock) 2017 sock_lock_init_class_and_name( 2018 sk, 2019 af_family_kern_slock_key_strings[sk->sk_family], 2020 af_family_kern_slock_keys + sk->sk_family, 2021 af_family_kern_key_strings[sk->sk_family], 2022 af_family_kern_keys + sk->sk_family); 2023 else 2024 sock_lock_init_class_and_name( 2025 sk, 2026 af_family_slock_key_strings[sk->sk_family], 2027 af_family_slock_keys + sk->sk_family, 2028 af_family_key_strings[sk->sk_family], 2029 af_family_keys + sk->sk_family); 2030 } 2031 2032 /* 2033 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 2034 * even temporarly, because of RCU lookups. sk_node should also be left as is. 2035 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 2036 */ 2037 static void sock_copy(struct sock *nsk, const struct sock *osk) 2038 { 2039 const struct proto *prot = READ_ONCE(osk->sk_prot); 2040 #ifdef CONFIG_SECURITY_NETWORK 2041 void *sptr = nsk->sk_security; 2042 #endif 2043 2044 /* If we move sk_tx_queue_mapping out of the private section, 2045 * we must check if sk_tx_queue_clear() is called after 2046 * sock_copy() in sk_clone_lock(). 2047 */ 2048 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) < 2049 offsetof(struct sock, sk_dontcopy_begin) || 2050 offsetof(struct sock, sk_tx_queue_mapping) >= 2051 offsetof(struct sock, sk_dontcopy_end)); 2052 2053 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 2054 2055 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 2056 prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 2057 2058 #ifdef CONFIG_SECURITY_NETWORK 2059 nsk->sk_security = sptr; 2060 security_sk_clone(osk, nsk); 2061 #endif 2062 } 2063 2064 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 2065 int family) 2066 { 2067 struct sock *sk; 2068 struct kmem_cache *slab; 2069 2070 slab = prot->slab; 2071 if (slab != NULL) { 2072 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 2073 if (!sk) 2074 return sk; 2075 if (want_init_on_alloc(priority)) 2076 sk_prot_clear_nulls(sk, prot->obj_size); 2077 } else 2078 sk = kmalloc(prot->obj_size, priority); 2079 2080 if (sk != NULL) { 2081 if (security_sk_alloc(sk, family, priority)) 2082 goto out_free; 2083 2084 if (!try_module_get(prot->owner)) 2085 goto out_free_sec; 2086 } 2087 2088 return sk; 2089 2090 out_free_sec: 2091 security_sk_free(sk); 2092 out_free: 2093 if (slab != NULL) 2094 kmem_cache_free(slab, sk); 2095 else 2096 kfree(sk); 2097 return NULL; 2098 } 2099 2100 static void sk_prot_free(struct proto *prot, struct sock *sk) 2101 { 2102 struct kmem_cache *slab; 2103 struct module *owner; 2104 2105 owner = prot->owner; 2106 slab = prot->slab; 2107 2108 cgroup_sk_free(&sk->sk_cgrp_data); 2109 mem_cgroup_sk_free(sk); 2110 security_sk_free(sk); 2111 if (slab != NULL) 2112 kmem_cache_free(slab, sk); 2113 else 2114 kfree(sk); 2115 module_put(owner); 2116 } 2117 2118 /** 2119 * sk_alloc - All socket objects are allocated here 2120 * @net: the applicable net namespace 2121 * @family: protocol family 2122 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 2123 * @prot: struct proto associated with this new sock instance 2124 * @kern: is this to be a kernel socket? 2125 */ 2126 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 2127 struct proto *prot, int kern) 2128 { 2129 struct sock *sk; 2130 2131 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 2132 if (sk) { 2133 sk->sk_family = family; 2134 /* 2135 * See comment in struct sock definition to understand 2136 * why we need sk_prot_creator -acme 2137 */ 2138 sk->sk_prot = sk->sk_prot_creator = prot; 2139 sk->sk_kern_sock = kern; 2140 sock_lock_init(sk); 2141 sk->sk_net_refcnt = kern ? 0 : 1; 2142 if (likely(sk->sk_net_refcnt)) { 2143 get_net_track(net, &sk->ns_tracker, priority); 2144 sock_inuse_add(net, 1); 2145 } else { 2146 __netns_tracker_alloc(net, &sk->ns_tracker, 2147 false, priority); 2148 } 2149 2150 sock_net_set(sk, net); 2151 refcount_set(&sk->sk_wmem_alloc, 1); 2152 2153 mem_cgroup_sk_alloc(sk); 2154 cgroup_sk_alloc(&sk->sk_cgrp_data); 2155 sock_update_classid(&sk->sk_cgrp_data); 2156 sock_update_netprioidx(&sk->sk_cgrp_data); 2157 sk_tx_queue_clear(sk); 2158 } 2159 2160 return sk; 2161 } 2162 EXPORT_SYMBOL(sk_alloc); 2163 2164 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 2165 * grace period. This is the case for UDP sockets and TCP listeners. 2166 */ 2167 static void __sk_destruct(struct rcu_head *head) 2168 { 2169 struct sock *sk = container_of(head, struct sock, sk_rcu); 2170 struct sk_filter *filter; 2171 2172 if (sk->sk_destruct) 2173 sk->sk_destruct(sk); 2174 2175 filter = rcu_dereference_check(sk->sk_filter, 2176 refcount_read(&sk->sk_wmem_alloc) == 0); 2177 if (filter) { 2178 sk_filter_uncharge(sk, filter); 2179 RCU_INIT_POINTER(sk->sk_filter, NULL); 2180 } 2181 2182 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 2183 2184 #ifdef CONFIG_BPF_SYSCALL 2185 bpf_sk_storage_free(sk); 2186 #endif 2187 2188 if (atomic_read(&sk->sk_omem_alloc)) 2189 pr_debug("%s: optmem leakage (%d bytes) detected\n", 2190 __func__, atomic_read(&sk->sk_omem_alloc)); 2191 2192 if (sk->sk_frag.page) { 2193 put_page(sk->sk_frag.page); 2194 sk->sk_frag.page = NULL; 2195 } 2196 2197 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */ 2198 put_cred(sk->sk_peer_cred); 2199 put_pid(sk->sk_peer_pid); 2200 2201 if (likely(sk->sk_net_refcnt)) 2202 put_net_track(sock_net(sk), &sk->ns_tracker); 2203 else 2204 __netns_tracker_free(sock_net(sk), &sk->ns_tracker, false); 2205 2206 sk_prot_free(sk->sk_prot_creator, sk); 2207 } 2208 2209 void sk_destruct(struct sock *sk) 2210 { 2211 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE); 2212 2213 if (rcu_access_pointer(sk->sk_reuseport_cb)) { 2214 reuseport_detach_sock(sk); 2215 use_call_rcu = true; 2216 } 2217 2218 if (use_call_rcu) 2219 call_rcu(&sk->sk_rcu, __sk_destruct); 2220 else 2221 __sk_destruct(&sk->sk_rcu); 2222 } 2223 2224 static void __sk_free(struct sock *sk) 2225 { 2226 if (likely(sk->sk_net_refcnt)) 2227 sock_inuse_add(sock_net(sk), -1); 2228 2229 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk))) 2230 sock_diag_broadcast_destroy(sk); 2231 else 2232 sk_destruct(sk); 2233 } 2234 2235 void sk_free(struct sock *sk) 2236 { 2237 /* 2238 * We subtract one from sk_wmem_alloc and can know if 2239 * some packets are still in some tx queue. 2240 * If not null, sock_wfree() will call __sk_free(sk) later 2241 */ 2242 if (refcount_dec_and_test(&sk->sk_wmem_alloc)) 2243 __sk_free(sk); 2244 } 2245 EXPORT_SYMBOL(sk_free); 2246 2247 static void sk_init_common(struct sock *sk) 2248 { 2249 skb_queue_head_init(&sk->sk_receive_queue); 2250 skb_queue_head_init(&sk->sk_write_queue); 2251 skb_queue_head_init(&sk->sk_error_queue); 2252 2253 rwlock_init(&sk->sk_callback_lock); 2254 lockdep_set_class_and_name(&sk->sk_receive_queue.lock, 2255 af_rlock_keys + sk->sk_family, 2256 af_family_rlock_key_strings[sk->sk_family]); 2257 lockdep_set_class_and_name(&sk->sk_write_queue.lock, 2258 af_wlock_keys + sk->sk_family, 2259 af_family_wlock_key_strings[sk->sk_family]); 2260 lockdep_set_class_and_name(&sk->sk_error_queue.lock, 2261 af_elock_keys + sk->sk_family, 2262 af_family_elock_key_strings[sk->sk_family]); 2263 lockdep_set_class_and_name(&sk->sk_callback_lock, 2264 af_callback_keys + sk->sk_family, 2265 af_family_clock_key_strings[sk->sk_family]); 2266 } 2267 2268 /** 2269 * sk_clone_lock - clone a socket, and lock its clone 2270 * @sk: the socket to clone 2271 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 2272 * 2273 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 2274 */ 2275 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 2276 { 2277 struct proto *prot = READ_ONCE(sk->sk_prot); 2278 struct sk_filter *filter; 2279 bool is_charged = true; 2280 struct sock *newsk; 2281 2282 newsk = sk_prot_alloc(prot, priority, sk->sk_family); 2283 if (!newsk) 2284 goto out; 2285 2286 sock_copy(newsk, sk); 2287 2288 newsk->sk_prot_creator = prot; 2289 2290 /* SANITY */ 2291 if (likely(newsk->sk_net_refcnt)) { 2292 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority); 2293 sock_inuse_add(sock_net(newsk), 1); 2294 } else { 2295 /* Kernel sockets are not elevating the struct net refcount. 2296 * Instead, use a tracker to more easily detect if a layer 2297 * is not properly dismantling its kernel sockets at netns 2298 * destroy time. 2299 */ 2300 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker, 2301 false, priority); 2302 } 2303 sk_node_init(&newsk->sk_node); 2304 sock_lock_init(newsk); 2305 bh_lock_sock(newsk); 2306 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 2307 newsk->sk_backlog.len = 0; 2308 2309 atomic_set(&newsk->sk_rmem_alloc, 0); 2310 2311 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */ 2312 refcount_set(&newsk->sk_wmem_alloc, 1); 2313 2314 atomic_set(&newsk->sk_omem_alloc, 0); 2315 sk_init_common(newsk); 2316 2317 newsk->sk_dst_cache = NULL; 2318 newsk->sk_dst_pending_confirm = 0; 2319 newsk->sk_wmem_queued = 0; 2320 newsk->sk_forward_alloc = 0; 2321 newsk->sk_reserved_mem = 0; 2322 atomic_set(&newsk->sk_drops, 0); 2323 newsk->sk_send_head = NULL; 2324 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 2325 atomic_set(&newsk->sk_zckey, 0); 2326 2327 sock_reset_flag(newsk, SOCK_DONE); 2328 2329 /* sk->sk_memcg will be populated at accept() time */ 2330 newsk->sk_memcg = NULL; 2331 2332 cgroup_sk_clone(&newsk->sk_cgrp_data); 2333 2334 rcu_read_lock(); 2335 filter = rcu_dereference(sk->sk_filter); 2336 if (filter != NULL) 2337 /* though it's an empty new sock, the charging may fail 2338 * if sysctl_optmem_max was changed between creation of 2339 * original socket and cloning 2340 */ 2341 is_charged = sk_filter_charge(newsk, filter); 2342 RCU_INIT_POINTER(newsk->sk_filter, filter); 2343 rcu_read_unlock(); 2344 2345 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 2346 /* We need to make sure that we don't uncharge the new 2347 * socket if we couldn't charge it in the first place 2348 * as otherwise we uncharge the parent's filter. 2349 */ 2350 if (!is_charged) 2351 RCU_INIT_POINTER(newsk->sk_filter, NULL); 2352 sk_free_unlock_clone(newsk); 2353 newsk = NULL; 2354 goto out; 2355 } 2356 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 2357 2358 if (bpf_sk_storage_clone(sk, newsk)) { 2359 sk_free_unlock_clone(newsk); 2360 newsk = NULL; 2361 goto out; 2362 } 2363 2364 /* Clear sk_user_data if parent had the pointer tagged 2365 * as not suitable for copying when cloning. 2366 */ 2367 if (sk_user_data_is_nocopy(newsk)) 2368 newsk->sk_user_data = NULL; 2369 2370 newsk->sk_err = 0; 2371 newsk->sk_err_soft = 0; 2372 newsk->sk_priority = 0; 2373 newsk->sk_incoming_cpu = raw_smp_processor_id(); 2374 2375 /* Before updating sk_refcnt, we must commit prior changes to memory 2376 * (Documentation/RCU/rculist_nulls.rst for details) 2377 */ 2378 smp_wmb(); 2379 refcount_set(&newsk->sk_refcnt, 2); 2380 2381 sk_set_socket(newsk, NULL); 2382 sk_tx_queue_clear(newsk); 2383 RCU_INIT_POINTER(newsk->sk_wq, NULL); 2384 2385 if (newsk->sk_prot->sockets_allocated) 2386 sk_sockets_allocated_inc(newsk); 2387 2388 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP) 2389 net_enable_timestamp(); 2390 out: 2391 return newsk; 2392 } 2393 EXPORT_SYMBOL_GPL(sk_clone_lock); 2394 2395 void sk_free_unlock_clone(struct sock *sk) 2396 { 2397 /* It is still raw copy of parent, so invalidate 2398 * destructor and make plain sk_free() */ 2399 sk->sk_destruct = NULL; 2400 bh_unlock_sock(sk); 2401 sk_free(sk); 2402 } 2403 EXPORT_SYMBOL_GPL(sk_free_unlock_clone); 2404 2405 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst) 2406 { 2407 bool is_ipv6 = false; 2408 u32 max_size; 2409 2410 #if IS_ENABLED(CONFIG_IPV6) 2411 is_ipv6 = (sk->sk_family == AF_INET6 && 2412 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)); 2413 #endif 2414 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */ 2415 max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) : 2416 READ_ONCE(dst->dev->gso_ipv4_max_size); 2417 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk)) 2418 max_size = GSO_LEGACY_MAX_SIZE; 2419 2420 return max_size - (MAX_TCP_HEADER + 1); 2421 } 2422 2423 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 2424 { 2425 u32 max_segs = 1; 2426 2427 sk->sk_route_caps = dst->dev->features; 2428 if (sk_is_tcp(sk)) 2429 sk->sk_route_caps |= NETIF_F_GSO; 2430 if (sk->sk_route_caps & NETIF_F_GSO) 2431 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 2432 if (unlikely(sk->sk_gso_disabled)) 2433 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2434 if (sk_can_gso(sk)) { 2435 if (dst->header_len && !xfrm_dst_offload_ok(dst)) { 2436 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2437 } else { 2438 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 2439 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst); 2440 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */ 2441 max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1); 2442 } 2443 } 2444 sk->sk_gso_max_segs = max_segs; 2445 sk_dst_set(sk, dst); 2446 } 2447 EXPORT_SYMBOL_GPL(sk_setup_caps); 2448 2449 /* 2450 * Simple resource managers for sockets. 2451 */ 2452 2453 2454 /* 2455 * Write buffer destructor automatically called from kfree_skb. 2456 */ 2457 void sock_wfree(struct sk_buff *skb) 2458 { 2459 struct sock *sk = skb->sk; 2460 unsigned int len = skb->truesize; 2461 bool free; 2462 2463 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 2464 if (sock_flag(sk, SOCK_RCU_FREE) && 2465 sk->sk_write_space == sock_def_write_space) { 2466 rcu_read_lock(); 2467 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc); 2468 sock_def_write_space_wfree(sk); 2469 rcu_read_unlock(); 2470 if (unlikely(free)) 2471 __sk_free(sk); 2472 return; 2473 } 2474 2475 /* 2476 * Keep a reference on sk_wmem_alloc, this will be released 2477 * after sk_write_space() call 2478 */ 2479 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); 2480 sk->sk_write_space(sk); 2481 len = 1; 2482 } 2483 /* 2484 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 2485 * could not do because of in-flight packets 2486 */ 2487 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc)) 2488 __sk_free(sk); 2489 } 2490 EXPORT_SYMBOL(sock_wfree); 2491 2492 /* This variant of sock_wfree() is used by TCP, 2493 * since it sets SOCK_USE_WRITE_QUEUE. 2494 */ 2495 void __sock_wfree(struct sk_buff *skb) 2496 { 2497 struct sock *sk = skb->sk; 2498 2499 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 2500 __sk_free(sk); 2501 } 2502 2503 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 2504 { 2505 skb_orphan(skb); 2506 skb->sk = sk; 2507 #ifdef CONFIG_INET 2508 if (unlikely(!sk_fullsock(sk))) { 2509 skb->destructor = sock_edemux; 2510 sock_hold(sk); 2511 return; 2512 } 2513 #endif 2514 skb->destructor = sock_wfree; 2515 skb_set_hash_from_sk(skb, sk); 2516 /* 2517 * We used to take a refcount on sk, but following operation 2518 * is enough to guarantee sk_free() wont free this sock until 2519 * all in-flight packets are completed 2520 */ 2521 refcount_add(skb->truesize, &sk->sk_wmem_alloc); 2522 } 2523 EXPORT_SYMBOL(skb_set_owner_w); 2524 2525 static bool can_skb_orphan_partial(const struct sk_buff *skb) 2526 { 2527 #ifdef CONFIG_TLS_DEVICE 2528 /* Drivers depend on in-order delivery for crypto offload, 2529 * partial orphan breaks out-of-order-OK logic. 2530 */ 2531 if (skb->decrypted) 2532 return false; 2533 #endif 2534 return (skb->destructor == sock_wfree || 2535 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree)); 2536 } 2537 2538 /* This helper is used by netem, as it can hold packets in its 2539 * delay queue. We want to allow the owner socket to send more 2540 * packets, as if they were already TX completed by a typical driver. 2541 * But we also want to keep skb->sk set because some packet schedulers 2542 * rely on it (sch_fq for example). 2543 */ 2544 void skb_orphan_partial(struct sk_buff *skb) 2545 { 2546 if (skb_is_tcp_pure_ack(skb)) 2547 return; 2548 2549 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk)) 2550 return; 2551 2552 skb_orphan(skb); 2553 } 2554 EXPORT_SYMBOL(skb_orphan_partial); 2555 2556 /* 2557 * Read buffer destructor automatically called from kfree_skb. 2558 */ 2559 void sock_rfree(struct sk_buff *skb) 2560 { 2561 struct sock *sk = skb->sk; 2562 unsigned int len = skb->truesize; 2563 2564 atomic_sub(len, &sk->sk_rmem_alloc); 2565 sk_mem_uncharge(sk, len); 2566 } 2567 EXPORT_SYMBOL(sock_rfree); 2568 2569 /* 2570 * Buffer destructor for skbs that are not used directly in read or write 2571 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 2572 */ 2573 void sock_efree(struct sk_buff *skb) 2574 { 2575 sock_put(skb->sk); 2576 } 2577 EXPORT_SYMBOL(sock_efree); 2578 2579 /* Buffer destructor for prefetch/receive path where reference count may 2580 * not be held, e.g. for listen sockets. 2581 */ 2582 #ifdef CONFIG_INET 2583 void sock_pfree(struct sk_buff *skb) 2584 { 2585 if (sk_is_refcounted(skb->sk)) 2586 sock_gen_put(skb->sk); 2587 } 2588 EXPORT_SYMBOL(sock_pfree); 2589 #endif /* CONFIG_INET */ 2590 2591 kuid_t sock_i_uid(struct sock *sk) 2592 { 2593 kuid_t uid; 2594 2595 read_lock_bh(&sk->sk_callback_lock); 2596 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 2597 read_unlock_bh(&sk->sk_callback_lock); 2598 return uid; 2599 } 2600 EXPORT_SYMBOL(sock_i_uid); 2601 2602 unsigned long __sock_i_ino(struct sock *sk) 2603 { 2604 unsigned long ino; 2605 2606 read_lock(&sk->sk_callback_lock); 2607 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 2608 read_unlock(&sk->sk_callback_lock); 2609 return ino; 2610 } 2611 EXPORT_SYMBOL(__sock_i_ino); 2612 2613 unsigned long sock_i_ino(struct sock *sk) 2614 { 2615 unsigned long ino; 2616 2617 local_bh_disable(); 2618 ino = __sock_i_ino(sk); 2619 local_bh_enable(); 2620 return ino; 2621 } 2622 EXPORT_SYMBOL(sock_i_ino); 2623 2624 /* 2625 * Allocate a skb from the socket's send buffer. 2626 */ 2627 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 2628 gfp_t priority) 2629 { 2630 if (force || 2631 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) { 2632 struct sk_buff *skb = alloc_skb(size, priority); 2633 2634 if (skb) { 2635 skb_set_owner_w(skb, sk); 2636 return skb; 2637 } 2638 } 2639 return NULL; 2640 } 2641 EXPORT_SYMBOL(sock_wmalloc); 2642 2643 static void sock_ofree(struct sk_buff *skb) 2644 { 2645 struct sock *sk = skb->sk; 2646 2647 atomic_sub(skb->truesize, &sk->sk_omem_alloc); 2648 } 2649 2650 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 2651 gfp_t priority) 2652 { 2653 struct sk_buff *skb; 2654 2655 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */ 2656 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) > 2657 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max)) 2658 return NULL; 2659 2660 skb = alloc_skb(size, priority); 2661 if (!skb) 2662 return NULL; 2663 2664 atomic_add(skb->truesize, &sk->sk_omem_alloc); 2665 skb->sk = sk; 2666 skb->destructor = sock_ofree; 2667 return skb; 2668 } 2669 2670 /* 2671 * Allocate a memory block from the socket's option memory buffer. 2672 */ 2673 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 2674 { 2675 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max); 2676 2677 if ((unsigned int)size <= optmem_max && 2678 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) { 2679 void *mem; 2680 /* First do the add, to avoid the race if kmalloc 2681 * might sleep. 2682 */ 2683 atomic_add(size, &sk->sk_omem_alloc); 2684 mem = kmalloc(size, priority); 2685 if (mem) 2686 return mem; 2687 atomic_sub(size, &sk->sk_omem_alloc); 2688 } 2689 return NULL; 2690 } 2691 EXPORT_SYMBOL(sock_kmalloc); 2692 2693 /* Free an option memory block. Note, we actually want the inline 2694 * here as this allows gcc to detect the nullify and fold away the 2695 * condition entirely. 2696 */ 2697 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 2698 const bool nullify) 2699 { 2700 if (WARN_ON_ONCE(!mem)) 2701 return; 2702 if (nullify) 2703 kfree_sensitive(mem); 2704 else 2705 kfree(mem); 2706 atomic_sub(size, &sk->sk_omem_alloc); 2707 } 2708 2709 void sock_kfree_s(struct sock *sk, void *mem, int size) 2710 { 2711 __sock_kfree_s(sk, mem, size, false); 2712 } 2713 EXPORT_SYMBOL(sock_kfree_s); 2714 2715 void sock_kzfree_s(struct sock *sk, void *mem, int size) 2716 { 2717 __sock_kfree_s(sk, mem, size, true); 2718 } 2719 EXPORT_SYMBOL(sock_kzfree_s); 2720 2721 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 2722 I think, these locks should be removed for datagram sockets. 2723 */ 2724 static long sock_wait_for_wmem(struct sock *sk, long timeo) 2725 { 2726 DEFINE_WAIT(wait); 2727 2728 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2729 for (;;) { 2730 if (!timeo) 2731 break; 2732 if (signal_pending(current)) 2733 break; 2734 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2735 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 2736 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) 2737 break; 2738 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN) 2739 break; 2740 if (READ_ONCE(sk->sk_err)) 2741 break; 2742 timeo = schedule_timeout(timeo); 2743 } 2744 finish_wait(sk_sleep(sk), &wait); 2745 return timeo; 2746 } 2747 2748 2749 /* 2750 * Generic send/receive buffer handlers 2751 */ 2752 2753 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 2754 unsigned long data_len, int noblock, 2755 int *errcode, int max_page_order) 2756 { 2757 struct sk_buff *skb; 2758 long timeo; 2759 int err; 2760 2761 timeo = sock_sndtimeo(sk, noblock); 2762 for (;;) { 2763 err = sock_error(sk); 2764 if (err != 0) 2765 goto failure; 2766 2767 err = -EPIPE; 2768 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN) 2769 goto failure; 2770 2771 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf)) 2772 break; 2773 2774 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2775 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2776 err = -EAGAIN; 2777 if (!timeo) 2778 goto failure; 2779 if (signal_pending(current)) 2780 goto interrupted; 2781 timeo = sock_wait_for_wmem(sk, timeo); 2782 } 2783 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 2784 errcode, sk->sk_allocation); 2785 if (skb) 2786 skb_set_owner_w(skb, sk); 2787 return skb; 2788 2789 interrupted: 2790 err = sock_intr_errno(timeo); 2791 failure: 2792 *errcode = err; 2793 return NULL; 2794 } 2795 EXPORT_SYMBOL(sock_alloc_send_pskb); 2796 2797 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 2798 struct sockcm_cookie *sockc) 2799 { 2800 u32 tsflags; 2801 2802 switch (cmsg->cmsg_type) { 2803 case SO_MARK: 2804 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && 2805 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 2806 return -EPERM; 2807 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2808 return -EINVAL; 2809 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 2810 break; 2811 case SO_TIMESTAMPING_OLD: 2812 case SO_TIMESTAMPING_NEW: 2813 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2814 return -EINVAL; 2815 2816 tsflags = *(u32 *)CMSG_DATA(cmsg); 2817 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 2818 return -EINVAL; 2819 2820 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 2821 sockc->tsflags |= tsflags; 2822 break; 2823 case SCM_TXTIME: 2824 if (!sock_flag(sk, SOCK_TXTIME)) 2825 return -EINVAL; 2826 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64))) 2827 return -EINVAL; 2828 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg)); 2829 break; 2830 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 2831 case SCM_RIGHTS: 2832 case SCM_CREDENTIALS: 2833 break; 2834 default: 2835 return -EINVAL; 2836 } 2837 return 0; 2838 } 2839 EXPORT_SYMBOL(__sock_cmsg_send); 2840 2841 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 2842 struct sockcm_cookie *sockc) 2843 { 2844 struct cmsghdr *cmsg; 2845 int ret; 2846 2847 for_each_cmsghdr(cmsg, msg) { 2848 if (!CMSG_OK(msg, cmsg)) 2849 return -EINVAL; 2850 if (cmsg->cmsg_level != SOL_SOCKET) 2851 continue; 2852 ret = __sock_cmsg_send(sk, cmsg, sockc); 2853 if (ret) 2854 return ret; 2855 } 2856 return 0; 2857 } 2858 EXPORT_SYMBOL(sock_cmsg_send); 2859 2860 static void sk_enter_memory_pressure(struct sock *sk) 2861 { 2862 if (!sk->sk_prot->enter_memory_pressure) 2863 return; 2864 2865 sk->sk_prot->enter_memory_pressure(sk); 2866 } 2867 2868 static void sk_leave_memory_pressure(struct sock *sk) 2869 { 2870 if (sk->sk_prot->leave_memory_pressure) { 2871 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure, 2872 tcp_leave_memory_pressure, sk); 2873 } else { 2874 unsigned long *memory_pressure = sk->sk_prot->memory_pressure; 2875 2876 if (memory_pressure && READ_ONCE(*memory_pressure)) 2877 WRITE_ONCE(*memory_pressure, 0); 2878 } 2879 } 2880 2881 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2882 2883 /** 2884 * skb_page_frag_refill - check that a page_frag contains enough room 2885 * @sz: minimum size of the fragment we want to get 2886 * @pfrag: pointer to page_frag 2887 * @gfp: priority for memory allocation 2888 * 2889 * Note: While this allocator tries to use high order pages, there is 2890 * no guarantee that allocations succeed. Therefore, @sz MUST be 2891 * less or equal than PAGE_SIZE. 2892 */ 2893 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 2894 { 2895 if (pfrag->page) { 2896 if (page_ref_count(pfrag->page) == 1) { 2897 pfrag->offset = 0; 2898 return true; 2899 } 2900 if (pfrag->offset + sz <= pfrag->size) 2901 return true; 2902 put_page(pfrag->page); 2903 } 2904 2905 pfrag->offset = 0; 2906 if (SKB_FRAG_PAGE_ORDER && 2907 !static_branch_unlikely(&net_high_order_alloc_disable_key)) { 2908 /* Avoid direct reclaim but allow kswapd to wake */ 2909 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 2910 __GFP_COMP | __GFP_NOWARN | 2911 __GFP_NORETRY, 2912 SKB_FRAG_PAGE_ORDER); 2913 if (likely(pfrag->page)) { 2914 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 2915 return true; 2916 } 2917 } 2918 pfrag->page = alloc_page(gfp); 2919 if (likely(pfrag->page)) { 2920 pfrag->size = PAGE_SIZE; 2921 return true; 2922 } 2923 return false; 2924 } 2925 EXPORT_SYMBOL(skb_page_frag_refill); 2926 2927 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 2928 { 2929 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 2930 return true; 2931 2932 sk_enter_memory_pressure(sk); 2933 sk_stream_moderate_sndbuf(sk); 2934 return false; 2935 } 2936 EXPORT_SYMBOL(sk_page_frag_refill); 2937 2938 void __lock_sock(struct sock *sk) 2939 __releases(&sk->sk_lock.slock) 2940 __acquires(&sk->sk_lock.slock) 2941 { 2942 DEFINE_WAIT(wait); 2943 2944 for (;;) { 2945 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2946 TASK_UNINTERRUPTIBLE); 2947 spin_unlock_bh(&sk->sk_lock.slock); 2948 schedule(); 2949 spin_lock_bh(&sk->sk_lock.slock); 2950 if (!sock_owned_by_user(sk)) 2951 break; 2952 } 2953 finish_wait(&sk->sk_lock.wq, &wait); 2954 } 2955 2956 void __release_sock(struct sock *sk) 2957 __releases(&sk->sk_lock.slock) 2958 __acquires(&sk->sk_lock.slock) 2959 { 2960 struct sk_buff *skb, *next; 2961 2962 while ((skb = sk->sk_backlog.head) != NULL) { 2963 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 2964 2965 spin_unlock_bh(&sk->sk_lock.slock); 2966 2967 do { 2968 next = skb->next; 2969 prefetch(next); 2970 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb)); 2971 skb_mark_not_on_list(skb); 2972 sk_backlog_rcv(sk, skb); 2973 2974 cond_resched(); 2975 2976 skb = next; 2977 } while (skb != NULL); 2978 2979 spin_lock_bh(&sk->sk_lock.slock); 2980 } 2981 2982 /* 2983 * Doing the zeroing here guarantee we can not loop forever 2984 * while a wild producer attempts to flood us. 2985 */ 2986 sk->sk_backlog.len = 0; 2987 } 2988 2989 void __sk_flush_backlog(struct sock *sk) 2990 { 2991 spin_lock_bh(&sk->sk_lock.slock); 2992 __release_sock(sk); 2993 2994 if (sk->sk_prot->release_cb) 2995 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb, 2996 tcp_release_cb, sk); 2997 2998 spin_unlock_bh(&sk->sk_lock.slock); 2999 } 3000 EXPORT_SYMBOL_GPL(__sk_flush_backlog); 3001 3002 /** 3003 * sk_wait_data - wait for data to arrive at sk_receive_queue 3004 * @sk: sock to wait on 3005 * @timeo: for how long 3006 * @skb: last skb seen on sk_receive_queue 3007 * 3008 * Now socket state including sk->sk_err is changed only under lock, 3009 * hence we may omit checks after joining wait queue. 3010 * We check receive queue before schedule() only as optimization; 3011 * it is very likely that release_sock() added new data. 3012 */ 3013 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 3014 { 3015 DEFINE_WAIT_FUNC(wait, woken_wake_function); 3016 int rc; 3017 3018 add_wait_queue(sk_sleep(sk), &wait); 3019 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 3020 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); 3021 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 3022 remove_wait_queue(sk_sleep(sk), &wait); 3023 return rc; 3024 } 3025 EXPORT_SYMBOL(sk_wait_data); 3026 3027 /** 3028 * __sk_mem_raise_allocated - increase memory_allocated 3029 * @sk: socket 3030 * @size: memory size to allocate 3031 * @amt: pages to allocate 3032 * @kind: allocation type 3033 * 3034 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc. 3035 * 3036 * Unlike the globally shared limits among the sockets under same protocol, 3037 * consuming the budget of a memcg won't have direct effect on other ones. 3038 * So be optimistic about memcg's tolerance, and leave the callers to decide 3039 * whether or not to raise allocated through sk_under_memory_pressure() or 3040 * its variants. 3041 */ 3042 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) 3043 { 3044 struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL; 3045 struct proto *prot = sk->sk_prot; 3046 bool charged = false; 3047 long allocated; 3048 3049 sk_memory_allocated_add(sk, amt); 3050 allocated = sk_memory_allocated(sk); 3051 3052 if (memcg) { 3053 if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge())) 3054 goto suppress_allocation; 3055 charged = true; 3056 } 3057 3058 /* Under limit. */ 3059 if (allocated <= sk_prot_mem_limits(sk, 0)) { 3060 sk_leave_memory_pressure(sk); 3061 return 1; 3062 } 3063 3064 /* Under pressure. */ 3065 if (allocated > sk_prot_mem_limits(sk, 1)) 3066 sk_enter_memory_pressure(sk); 3067 3068 /* Over hard limit. */ 3069 if (allocated > sk_prot_mem_limits(sk, 2)) 3070 goto suppress_allocation; 3071 3072 /* Guarantee minimum buffer size under pressure (either global 3073 * or memcg) to make sure features described in RFC 7323 (TCP 3074 * Extensions for High Performance) work properly. 3075 * 3076 * This rule does NOT stand when exceeds global or memcg's hard 3077 * limit, or else a DoS attack can be taken place by spawning 3078 * lots of sockets whose usage are under minimum buffer size. 3079 */ 3080 if (kind == SK_MEM_RECV) { 3081 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot)) 3082 return 1; 3083 3084 } else { /* SK_MEM_SEND */ 3085 int wmem0 = sk_get_wmem0(sk, prot); 3086 3087 if (sk->sk_type == SOCK_STREAM) { 3088 if (sk->sk_wmem_queued < wmem0) 3089 return 1; 3090 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) { 3091 return 1; 3092 } 3093 } 3094 3095 if (sk_has_memory_pressure(sk)) { 3096 u64 alloc; 3097 3098 /* The following 'average' heuristic is within the 3099 * scope of global accounting, so it only makes 3100 * sense for global memory pressure. 3101 */ 3102 if (!sk_under_global_memory_pressure(sk)) 3103 return 1; 3104 3105 /* Try to be fair among all the sockets under global 3106 * pressure by allowing the ones that below average 3107 * usage to raise. 3108 */ 3109 alloc = sk_sockets_allocated_read_positive(sk); 3110 if (sk_prot_mem_limits(sk, 2) > alloc * 3111 sk_mem_pages(sk->sk_wmem_queued + 3112 atomic_read(&sk->sk_rmem_alloc) + 3113 sk->sk_forward_alloc)) 3114 return 1; 3115 } 3116 3117 suppress_allocation: 3118 3119 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 3120 sk_stream_moderate_sndbuf(sk); 3121 3122 /* Fail only if socket is _under_ its sndbuf. 3123 * In this case we cannot block, so that we have to fail. 3124 */ 3125 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) { 3126 /* Force charge with __GFP_NOFAIL */ 3127 if (memcg && !charged) { 3128 mem_cgroup_charge_skmem(memcg, amt, 3129 gfp_memcg_charge() | __GFP_NOFAIL); 3130 } 3131 return 1; 3132 } 3133 } 3134 3135 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) 3136 trace_sock_exceed_buf_limit(sk, prot, allocated, kind); 3137 3138 sk_memory_allocated_sub(sk, amt); 3139 3140 if (charged) 3141 mem_cgroup_uncharge_skmem(memcg, amt); 3142 3143 return 0; 3144 } 3145 3146 /** 3147 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 3148 * @sk: socket 3149 * @size: memory size to allocate 3150 * @kind: allocation type 3151 * 3152 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 3153 * rmem allocation. This function assumes that protocols which have 3154 * memory_pressure use sk_wmem_queued as write buffer accounting. 3155 */ 3156 int __sk_mem_schedule(struct sock *sk, int size, int kind) 3157 { 3158 int ret, amt = sk_mem_pages(size); 3159 3160 sk_forward_alloc_add(sk, amt << PAGE_SHIFT); 3161 ret = __sk_mem_raise_allocated(sk, size, amt, kind); 3162 if (!ret) 3163 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT)); 3164 return ret; 3165 } 3166 EXPORT_SYMBOL(__sk_mem_schedule); 3167 3168 /** 3169 * __sk_mem_reduce_allocated - reclaim memory_allocated 3170 * @sk: socket 3171 * @amount: number of quanta 3172 * 3173 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc 3174 */ 3175 void __sk_mem_reduce_allocated(struct sock *sk, int amount) 3176 { 3177 sk_memory_allocated_sub(sk, amount); 3178 3179 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 3180 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 3181 3182 if (sk_under_global_memory_pressure(sk) && 3183 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 3184 sk_leave_memory_pressure(sk); 3185 } 3186 3187 /** 3188 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated 3189 * @sk: socket 3190 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple) 3191 */ 3192 void __sk_mem_reclaim(struct sock *sk, int amount) 3193 { 3194 amount >>= PAGE_SHIFT; 3195 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT)); 3196 __sk_mem_reduce_allocated(sk, amount); 3197 } 3198 EXPORT_SYMBOL(__sk_mem_reclaim); 3199 3200 int sk_set_peek_off(struct sock *sk, int val) 3201 { 3202 WRITE_ONCE(sk->sk_peek_off, val); 3203 return 0; 3204 } 3205 EXPORT_SYMBOL_GPL(sk_set_peek_off); 3206 3207 /* 3208 * Set of default routines for initialising struct proto_ops when 3209 * the protocol does not support a particular function. In certain 3210 * cases where it makes no sense for a protocol to have a "do nothing" 3211 * function, some default processing is provided. 3212 */ 3213 3214 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 3215 { 3216 return -EOPNOTSUPP; 3217 } 3218 EXPORT_SYMBOL(sock_no_bind); 3219 3220 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 3221 int len, int flags) 3222 { 3223 return -EOPNOTSUPP; 3224 } 3225 EXPORT_SYMBOL(sock_no_connect); 3226 3227 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 3228 { 3229 return -EOPNOTSUPP; 3230 } 3231 EXPORT_SYMBOL(sock_no_socketpair); 3232 3233 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags, 3234 bool kern) 3235 { 3236 return -EOPNOTSUPP; 3237 } 3238 EXPORT_SYMBOL(sock_no_accept); 3239 3240 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 3241 int peer) 3242 { 3243 return -EOPNOTSUPP; 3244 } 3245 EXPORT_SYMBOL(sock_no_getname); 3246 3247 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 3248 { 3249 return -EOPNOTSUPP; 3250 } 3251 EXPORT_SYMBOL(sock_no_ioctl); 3252 3253 int sock_no_listen(struct socket *sock, int backlog) 3254 { 3255 return -EOPNOTSUPP; 3256 } 3257 EXPORT_SYMBOL(sock_no_listen); 3258 3259 int sock_no_shutdown(struct socket *sock, int how) 3260 { 3261 return -EOPNOTSUPP; 3262 } 3263 EXPORT_SYMBOL(sock_no_shutdown); 3264 3265 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 3266 { 3267 return -EOPNOTSUPP; 3268 } 3269 EXPORT_SYMBOL(sock_no_sendmsg); 3270 3271 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len) 3272 { 3273 return -EOPNOTSUPP; 3274 } 3275 EXPORT_SYMBOL(sock_no_sendmsg_locked); 3276 3277 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 3278 int flags) 3279 { 3280 return -EOPNOTSUPP; 3281 } 3282 EXPORT_SYMBOL(sock_no_recvmsg); 3283 3284 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 3285 { 3286 /* Mirror missing mmap method error code */ 3287 return -ENODEV; 3288 } 3289 EXPORT_SYMBOL(sock_no_mmap); 3290 3291 /* 3292 * When a file is received (via SCM_RIGHTS, etc), we must bump the 3293 * various sock-based usage counts. 3294 */ 3295 void __receive_sock(struct file *file) 3296 { 3297 struct socket *sock; 3298 3299 sock = sock_from_file(file); 3300 if (sock) { 3301 sock_update_netprioidx(&sock->sk->sk_cgrp_data); 3302 sock_update_classid(&sock->sk->sk_cgrp_data); 3303 } 3304 } 3305 3306 /* 3307 * Default Socket Callbacks 3308 */ 3309 3310 static void sock_def_wakeup(struct sock *sk) 3311 { 3312 struct socket_wq *wq; 3313 3314 rcu_read_lock(); 3315 wq = rcu_dereference(sk->sk_wq); 3316 if (skwq_has_sleeper(wq)) 3317 wake_up_interruptible_all(&wq->wait); 3318 rcu_read_unlock(); 3319 } 3320 3321 static void sock_def_error_report(struct sock *sk) 3322 { 3323 struct socket_wq *wq; 3324 3325 rcu_read_lock(); 3326 wq = rcu_dereference(sk->sk_wq); 3327 if (skwq_has_sleeper(wq)) 3328 wake_up_interruptible_poll(&wq->wait, EPOLLERR); 3329 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 3330 rcu_read_unlock(); 3331 } 3332 3333 void sock_def_readable(struct sock *sk) 3334 { 3335 struct socket_wq *wq; 3336 3337 trace_sk_data_ready(sk); 3338 3339 rcu_read_lock(); 3340 wq = rcu_dereference(sk->sk_wq); 3341 if (skwq_has_sleeper(wq)) 3342 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI | 3343 EPOLLRDNORM | EPOLLRDBAND); 3344 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 3345 rcu_read_unlock(); 3346 } 3347 3348 static void sock_def_write_space(struct sock *sk) 3349 { 3350 struct socket_wq *wq; 3351 3352 rcu_read_lock(); 3353 3354 /* Do not wake up a writer until he can make "significant" 3355 * progress. --DaveM 3356 */ 3357 if (sock_writeable(sk)) { 3358 wq = rcu_dereference(sk->sk_wq); 3359 if (skwq_has_sleeper(wq)) 3360 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 3361 EPOLLWRNORM | EPOLLWRBAND); 3362 3363 /* Should agree with poll, otherwise some programs break */ 3364 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 3365 } 3366 3367 rcu_read_unlock(); 3368 } 3369 3370 /* An optimised version of sock_def_write_space(), should only be called 3371 * for SOCK_RCU_FREE sockets under RCU read section and after putting 3372 * ->sk_wmem_alloc. 3373 */ 3374 static void sock_def_write_space_wfree(struct sock *sk) 3375 { 3376 /* Do not wake up a writer until he can make "significant" 3377 * progress. --DaveM 3378 */ 3379 if (sock_writeable(sk)) { 3380 struct socket_wq *wq = rcu_dereference(sk->sk_wq); 3381 3382 /* rely on refcount_sub from sock_wfree() */ 3383 smp_mb__after_atomic(); 3384 if (wq && waitqueue_active(&wq->wait)) 3385 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 3386 EPOLLWRNORM | EPOLLWRBAND); 3387 3388 /* Should agree with poll, otherwise some programs break */ 3389 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 3390 } 3391 } 3392 3393 static void sock_def_destruct(struct sock *sk) 3394 { 3395 } 3396 3397 void sk_send_sigurg(struct sock *sk) 3398 { 3399 if (sk->sk_socket && sk->sk_socket->file) 3400 if (send_sigurg(&sk->sk_socket->file->f_owner)) 3401 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 3402 } 3403 EXPORT_SYMBOL(sk_send_sigurg); 3404 3405 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 3406 unsigned long expires) 3407 { 3408 if (!mod_timer(timer, expires)) 3409 sock_hold(sk); 3410 } 3411 EXPORT_SYMBOL(sk_reset_timer); 3412 3413 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 3414 { 3415 if (del_timer(timer)) 3416 __sock_put(sk); 3417 } 3418 EXPORT_SYMBOL(sk_stop_timer); 3419 3420 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer) 3421 { 3422 if (del_timer_sync(timer)) 3423 __sock_put(sk); 3424 } 3425 EXPORT_SYMBOL(sk_stop_timer_sync); 3426 3427 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid) 3428 { 3429 sk_init_common(sk); 3430 sk->sk_send_head = NULL; 3431 3432 timer_setup(&sk->sk_timer, NULL, 0); 3433 3434 sk->sk_allocation = GFP_KERNEL; 3435 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default); 3436 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default); 3437 sk->sk_state = TCP_CLOSE; 3438 sk->sk_use_task_frag = true; 3439 sk_set_socket(sk, sock); 3440 3441 sock_set_flag(sk, SOCK_ZAPPED); 3442 3443 if (sock) { 3444 sk->sk_type = sock->type; 3445 RCU_INIT_POINTER(sk->sk_wq, &sock->wq); 3446 sock->sk = sk; 3447 } else { 3448 RCU_INIT_POINTER(sk->sk_wq, NULL); 3449 } 3450 sk->sk_uid = uid; 3451 3452 rwlock_init(&sk->sk_callback_lock); 3453 if (sk->sk_kern_sock) 3454 lockdep_set_class_and_name( 3455 &sk->sk_callback_lock, 3456 af_kern_callback_keys + sk->sk_family, 3457 af_family_kern_clock_key_strings[sk->sk_family]); 3458 else 3459 lockdep_set_class_and_name( 3460 &sk->sk_callback_lock, 3461 af_callback_keys + sk->sk_family, 3462 af_family_clock_key_strings[sk->sk_family]); 3463 3464 sk->sk_state_change = sock_def_wakeup; 3465 sk->sk_data_ready = sock_def_readable; 3466 sk->sk_write_space = sock_def_write_space; 3467 sk->sk_error_report = sock_def_error_report; 3468 sk->sk_destruct = sock_def_destruct; 3469 3470 sk->sk_frag.page = NULL; 3471 sk->sk_frag.offset = 0; 3472 sk->sk_peek_off = -1; 3473 3474 sk->sk_peer_pid = NULL; 3475 sk->sk_peer_cred = NULL; 3476 spin_lock_init(&sk->sk_peer_lock); 3477 3478 sk->sk_write_pending = 0; 3479 sk->sk_rcvlowat = 1; 3480 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 3481 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 3482 3483 sk->sk_stamp = SK_DEFAULT_STAMP; 3484 #if BITS_PER_LONG==32 3485 seqlock_init(&sk->sk_stamp_seq); 3486 #endif 3487 atomic_set(&sk->sk_zckey, 0); 3488 3489 #ifdef CONFIG_NET_RX_BUSY_POLL 3490 sk->sk_napi_id = 0; 3491 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read); 3492 #endif 3493 3494 sk->sk_max_pacing_rate = ~0UL; 3495 sk->sk_pacing_rate = ~0UL; 3496 WRITE_ONCE(sk->sk_pacing_shift, 10); 3497 sk->sk_incoming_cpu = -1; 3498 3499 sk_rx_queue_clear(sk); 3500 /* 3501 * Before updating sk_refcnt, we must commit prior changes to memory 3502 * (Documentation/RCU/rculist_nulls.rst for details) 3503 */ 3504 smp_wmb(); 3505 refcount_set(&sk->sk_refcnt, 1); 3506 atomic_set(&sk->sk_drops, 0); 3507 } 3508 EXPORT_SYMBOL(sock_init_data_uid); 3509 3510 void sock_init_data(struct socket *sock, struct sock *sk) 3511 { 3512 kuid_t uid = sock ? 3513 SOCK_INODE(sock)->i_uid : 3514 make_kuid(sock_net(sk)->user_ns, 0); 3515 3516 sock_init_data_uid(sock, sk, uid); 3517 } 3518 EXPORT_SYMBOL(sock_init_data); 3519 3520 void lock_sock_nested(struct sock *sk, int subclass) 3521 { 3522 /* The sk_lock has mutex_lock() semantics here. */ 3523 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 3524 3525 might_sleep(); 3526 spin_lock_bh(&sk->sk_lock.slock); 3527 if (sock_owned_by_user_nocheck(sk)) 3528 __lock_sock(sk); 3529 sk->sk_lock.owned = 1; 3530 spin_unlock_bh(&sk->sk_lock.slock); 3531 } 3532 EXPORT_SYMBOL(lock_sock_nested); 3533 3534 void release_sock(struct sock *sk) 3535 { 3536 spin_lock_bh(&sk->sk_lock.slock); 3537 if (sk->sk_backlog.tail) 3538 __release_sock(sk); 3539 3540 if (sk->sk_prot->release_cb) 3541 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb, 3542 tcp_release_cb, sk); 3543 3544 sock_release_ownership(sk); 3545 if (waitqueue_active(&sk->sk_lock.wq)) 3546 wake_up(&sk->sk_lock.wq); 3547 spin_unlock_bh(&sk->sk_lock.slock); 3548 } 3549 EXPORT_SYMBOL(release_sock); 3550 3551 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock) 3552 { 3553 might_sleep(); 3554 spin_lock_bh(&sk->sk_lock.slock); 3555 3556 if (!sock_owned_by_user_nocheck(sk)) { 3557 /* 3558 * Fast path return with bottom halves disabled and 3559 * sock::sk_lock.slock held. 3560 * 3561 * The 'mutex' is not contended and holding 3562 * sock::sk_lock.slock prevents all other lockers to 3563 * proceed so the corresponding unlock_sock_fast() can 3564 * avoid the slow path of release_sock() completely and 3565 * just release slock. 3566 * 3567 * From a semantical POV this is equivalent to 'acquiring' 3568 * the 'mutex', hence the corresponding lockdep 3569 * mutex_release() has to happen in the fast path of 3570 * unlock_sock_fast(). 3571 */ 3572 return false; 3573 } 3574 3575 __lock_sock(sk); 3576 sk->sk_lock.owned = 1; 3577 __acquire(&sk->sk_lock.slock); 3578 spin_unlock_bh(&sk->sk_lock.slock); 3579 return true; 3580 } 3581 EXPORT_SYMBOL(__lock_sock_fast); 3582 3583 int sock_gettstamp(struct socket *sock, void __user *userstamp, 3584 bool timeval, bool time32) 3585 { 3586 struct sock *sk = sock->sk; 3587 struct timespec64 ts; 3588 3589 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 3590 ts = ktime_to_timespec64(sock_read_timestamp(sk)); 3591 if (ts.tv_sec == -1) 3592 return -ENOENT; 3593 if (ts.tv_sec == 0) { 3594 ktime_t kt = ktime_get_real(); 3595 sock_write_timestamp(sk, kt); 3596 ts = ktime_to_timespec64(kt); 3597 } 3598 3599 if (timeval) 3600 ts.tv_nsec /= 1000; 3601 3602 #ifdef CONFIG_COMPAT_32BIT_TIME 3603 if (time32) 3604 return put_old_timespec32(&ts, userstamp); 3605 #endif 3606 #ifdef CONFIG_SPARC64 3607 /* beware of padding in sparc64 timeval */ 3608 if (timeval && !in_compat_syscall()) { 3609 struct __kernel_old_timeval __user tv = { 3610 .tv_sec = ts.tv_sec, 3611 .tv_usec = ts.tv_nsec, 3612 }; 3613 if (copy_to_user(userstamp, &tv, sizeof(tv))) 3614 return -EFAULT; 3615 return 0; 3616 } 3617 #endif 3618 return put_timespec64(&ts, userstamp); 3619 } 3620 EXPORT_SYMBOL(sock_gettstamp); 3621 3622 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag) 3623 { 3624 if (!sock_flag(sk, flag)) { 3625 unsigned long previous_flags = sk->sk_flags; 3626 3627 sock_set_flag(sk, flag); 3628 /* 3629 * we just set one of the two flags which require net 3630 * time stamping, but time stamping might have been on 3631 * already because of the other one 3632 */ 3633 if (sock_needs_netstamp(sk) && 3634 !(previous_flags & SK_FLAGS_TIMESTAMP)) 3635 net_enable_timestamp(); 3636 } 3637 } 3638 3639 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 3640 int level, int type) 3641 { 3642 struct sock_exterr_skb *serr; 3643 struct sk_buff *skb; 3644 int copied, err; 3645 3646 err = -EAGAIN; 3647 skb = sock_dequeue_err_skb(sk); 3648 if (skb == NULL) 3649 goto out; 3650 3651 copied = skb->len; 3652 if (copied > len) { 3653 msg->msg_flags |= MSG_TRUNC; 3654 copied = len; 3655 } 3656 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3657 if (err) 3658 goto out_free_skb; 3659 3660 sock_recv_timestamp(msg, sk, skb); 3661 3662 serr = SKB_EXT_ERR(skb); 3663 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 3664 3665 msg->msg_flags |= MSG_ERRQUEUE; 3666 err = copied; 3667 3668 out_free_skb: 3669 kfree_skb(skb); 3670 out: 3671 return err; 3672 } 3673 EXPORT_SYMBOL(sock_recv_errqueue); 3674 3675 /* 3676 * Get a socket option on an socket. 3677 * 3678 * FIX: POSIX 1003.1g is very ambiguous here. It states that 3679 * asynchronous errors should be reported by getsockopt. We assume 3680 * this means if you specify SO_ERROR (otherwise whats the point of it). 3681 */ 3682 int sock_common_getsockopt(struct socket *sock, int level, int optname, 3683 char __user *optval, int __user *optlen) 3684 { 3685 struct sock *sk = sock->sk; 3686 3687 /* IPV6_ADDRFORM can change sk->sk_prot under us. */ 3688 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen); 3689 } 3690 EXPORT_SYMBOL(sock_common_getsockopt); 3691 3692 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 3693 int flags) 3694 { 3695 struct sock *sk = sock->sk; 3696 int addr_len = 0; 3697 int err; 3698 3699 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len); 3700 if (err >= 0) 3701 msg->msg_namelen = addr_len; 3702 return err; 3703 } 3704 EXPORT_SYMBOL(sock_common_recvmsg); 3705 3706 /* 3707 * Set socket options on an inet socket. 3708 */ 3709 int sock_common_setsockopt(struct socket *sock, int level, int optname, 3710 sockptr_t optval, unsigned int optlen) 3711 { 3712 struct sock *sk = sock->sk; 3713 3714 /* IPV6_ADDRFORM can change sk->sk_prot under us. */ 3715 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen); 3716 } 3717 EXPORT_SYMBOL(sock_common_setsockopt); 3718 3719 void sk_common_release(struct sock *sk) 3720 { 3721 if (sk->sk_prot->destroy) 3722 sk->sk_prot->destroy(sk); 3723 3724 /* 3725 * Observation: when sk_common_release is called, processes have 3726 * no access to socket. But net still has. 3727 * Step one, detach it from networking: 3728 * 3729 * A. Remove from hash tables. 3730 */ 3731 3732 sk->sk_prot->unhash(sk); 3733 3734 /* 3735 * In this point socket cannot receive new packets, but it is possible 3736 * that some packets are in flight because some CPU runs receiver and 3737 * did hash table lookup before we unhashed socket. They will achieve 3738 * receive queue and will be purged by socket destructor. 3739 * 3740 * Also we still have packets pending on receive queue and probably, 3741 * our own packets waiting in device queues. sock_destroy will drain 3742 * receive queue, but transmitted packets will delay socket destruction 3743 * until the last reference will be released. 3744 */ 3745 3746 sock_orphan(sk); 3747 3748 xfrm_sk_free_policy(sk); 3749 3750 sock_put(sk); 3751 } 3752 EXPORT_SYMBOL(sk_common_release); 3753 3754 void sk_get_meminfo(const struct sock *sk, u32 *mem) 3755 { 3756 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); 3757 3758 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 3759 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf); 3760 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 3761 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf); 3762 mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk); 3763 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued); 3764 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 3765 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len); 3766 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); 3767 } 3768 3769 #ifdef CONFIG_PROC_FS 3770 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 3771 3772 int sock_prot_inuse_get(struct net *net, struct proto *prot) 3773 { 3774 int cpu, idx = prot->inuse_idx; 3775 int res = 0; 3776 3777 for_each_possible_cpu(cpu) 3778 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx]; 3779 3780 return res >= 0 ? res : 0; 3781 } 3782 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 3783 3784 int sock_inuse_get(struct net *net) 3785 { 3786 int cpu, res = 0; 3787 3788 for_each_possible_cpu(cpu) 3789 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all; 3790 3791 return res; 3792 } 3793 3794 EXPORT_SYMBOL_GPL(sock_inuse_get); 3795 3796 static int __net_init sock_inuse_init_net(struct net *net) 3797 { 3798 net->core.prot_inuse = alloc_percpu(struct prot_inuse); 3799 if (net->core.prot_inuse == NULL) 3800 return -ENOMEM; 3801 return 0; 3802 } 3803 3804 static void __net_exit sock_inuse_exit_net(struct net *net) 3805 { 3806 free_percpu(net->core.prot_inuse); 3807 } 3808 3809 static struct pernet_operations net_inuse_ops = { 3810 .init = sock_inuse_init_net, 3811 .exit = sock_inuse_exit_net, 3812 }; 3813 3814 static __init int net_inuse_init(void) 3815 { 3816 if (register_pernet_subsys(&net_inuse_ops)) 3817 panic("Cannot initialize net inuse counters"); 3818 3819 return 0; 3820 } 3821 3822 core_initcall(net_inuse_init); 3823 3824 static int assign_proto_idx(struct proto *prot) 3825 { 3826 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 3827 3828 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 3829 pr_err("PROTO_INUSE_NR exhausted\n"); 3830 return -ENOSPC; 3831 } 3832 3833 set_bit(prot->inuse_idx, proto_inuse_idx); 3834 return 0; 3835 } 3836 3837 static void release_proto_idx(struct proto *prot) 3838 { 3839 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 3840 clear_bit(prot->inuse_idx, proto_inuse_idx); 3841 } 3842 #else 3843 static inline int assign_proto_idx(struct proto *prot) 3844 { 3845 return 0; 3846 } 3847 3848 static inline void release_proto_idx(struct proto *prot) 3849 { 3850 } 3851 3852 #endif 3853 3854 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot) 3855 { 3856 if (!twsk_prot) 3857 return; 3858 kfree(twsk_prot->twsk_slab_name); 3859 twsk_prot->twsk_slab_name = NULL; 3860 kmem_cache_destroy(twsk_prot->twsk_slab); 3861 twsk_prot->twsk_slab = NULL; 3862 } 3863 3864 static int tw_prot_init(const struct proto *prot) 3865 { 3866 struct timewait_sock_ops *twsk_prot = prot->twsk_prot; 3867 3868 if (!twsk_prot) 3869 return 0; 3870 3871 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", 3872 prot->name); 3873 if (!twsk_prot->twsk_slab_name) 3874 return -ENOMEM; 3875 3876 twsk_prot->twsk_slab = 3877 kmem_cache_create(twsk_prot->twsk_slab_name, 3878 twsk_prot->twsk_obj_size, 0, 3879 SLAB_ACCOUNT | prot->slab_flags, 3880 NULL); 3881 if (!twsk_prot->twsk_slab) { 3882 pr_crit("%s: Can't create timewait sock SLAB cache!\n", 3883 prot->name); 3884 return -ENOMEM; 3885 } 3886 3887 return 0; 3888 } 3889 3890 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 3891 { 3892 if (!rsk_prot) 3893 return; 3894 kfree(rsk_prot->slab_name); 3895 rsk_prot->slab_name = NULL; 3896 kmem_cache_destroy(rsk_prot->slab); 3897 rsk_prot->slab = NULL; 3898 } 3899 3900 static int req_prot_init(const struct proto *prot) 3901 { 3902 struct request_sock_ops *rsk_prot = prot->rsk_prot; 3903 3904 if (!rsk_prot) 3905 return 0; 3906 3907 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 3908 prot->name); 3909 if (!rsk_prot->slab_name) 3910 return -ENOMEM; 3911 3912 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 3913 rsk_prot->obj_size, 0, 3914 SLAB_ACCOUNT | prot->slab_flags, 3915 NULL); 3916 3917 if (!rsk_prot->slab) { 3918 pr_crit("%s: Can't create request sock SLAB cache!\n", 3919 prot->name); 3920 return -ENOMEM; 3921 } 3922 return 0; 3923 } 3924 3925 int proto_register(struct proto *prot, int alloc_slab) 3926 { 3927 int ret = -ENOBUFS; 3928 3929 if (prot->memory_allocated && !prot->sysctl_mem) { 3930 pr_err("%s: missing sysctl_mem\n", prot->name); 3931 return -EINVAL; 3932 } 3933 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) { 3934 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name); 3935 return -EINVAL; 3936 } 3937 if (alloc_slab) { 3938 prot->slab = kmem_cache_create_usercopy(prot->name, 3939 prot->obj_size, 0, 3940 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | 3941 prot->slab_flags, 3942 prot->useroffset, prot->usersize, 3943 NULL); 3944 3945 if (prot->slab == NULL) { 3946 pr_crit("%s: Can't create sock SLAB cache!\n", 3947 prot->name); 3948 goto out; 3949 } 3950 3951 if (req_prot_init(prot)) 3952 goto out_free_request_sock_slab; 3953 3954 if (tw_prot_init(prot)) 3955 goto out_free_timewait_sock_slab; 3956 } 3957 3958 mutex_lock(&proto_list_mutex); 3959 ret = assign_proto_idx(prot); 3960 if (ret) { 3961 mutex_unlock(&proto_list_mutex); 3962 goto out_free_timewait_sock_slab; 3963 } 3964 list_add(&prot->node, &proto_list); 3965 mutex_unlock(&proto_list_mutex); 3966 return ret; 3967 3968 out_free_timewait_sock_slab: 3969 if (alloc_slab) 3970 tw_prot_cleanup(prot->twsk_prot); 3971 out_free_request_sock_slab: 3972 if (alloc_slab) { 3973 req_prot_cleanup(prot->rsk_prot); 3974 3975 kmem_cache_destroy(prot->slab); 3976 prot->slab = NULL; 3977 } 3978 out: 3979 return ret; 3980 } 3981 EXPORT_SYMBOL(proto_register); 3982 3983 void proto_unregister(struct proto *prot) 3984 { 3985 mutex_lock(&proto_list_mutex); 3986 release_proto_idx(prot); 3987 list_del(&prot->node); 3988 mutex_unlock(&proto_list_mutex); 3989 3990 kmem_cache_destroy(prot->slab); 3991 prot->slab = NULL; 3992 3993 req_prot_cleanup(prot->rsk_prot); 3994 tw_prot_cleanup(prot->twsk_prot); 3995 } 3996 EXPORT_SYMBOL(proto_unregister); 3997 3998 int sock_load_diag_module(int family, int protocol) 3999 { 4000 if (!protocol) { 4001 if (!sock_is_registered(family)) 4002 return -ENOENT; 4003 4004 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 4005 NETLINK_SOCK_DIAG, family); 4006 } 4007 4008 #ifdef CONFIG_INET 4009 if (family == AF_INET && 4010 protocol != IPPROTO_RAW && 4011 protocol < MAX_INET_PROTOS && 4012 !rcu_access_pointer(inet_protos[protocol])) 4013 return -ENOENT; 4014 #endif 4015 4016 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK, 4017 NETLINK_SOCK_DIAG, family, protocol); 4018 } 4019 EXPORT_SYMBOL(sock_load_diag_module); 4020 4021 #ifdef CONFIG_PROC_FS 4022 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 4023 __acquires(proto_list_mutex) 4024 { 4025 mutex_lock(&proto_list_mutex); 4026 return seq_list_start_head(&proto_list, *pos); 4027 } 4028 4029 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4030 { 4031 return seq_list_next(v, &proto_list, pos); 4032 } 4033 4034 static void proto_seq_stop(struct seq_file *seq, void *v) 4035 __releases(proto_list_mutex) 4036 { 4037 mutex_unlock(&proto_list_mutex); 4038 } 4039 4040 static char proto_method_implemented(const void *method) 4041 { 4042 return method == NULL ? 'n' : 'y'; 4043 } 4044 static long sock_prot_memory_allocated(struct proto *proto) 4045 { 4046 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 4047 } 4048 4049 static const char *sock_prot_memory_pressure(struct proto *proto) 4050 { 4051 return proto->memory_pressure != NULL ? 4052 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 4053 } 4054 4055 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 4056 { 4057 4058 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 4059 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 4060 proto->name, 4061 proto->obj_size, 4062 sock_prot_inuse_get(seq_file_net(seq), proto), 4063 sock_prot_memory_allocated(proto), 4064 sock_prot_memory_pressure(proto), 4065 proto->max_header, 4066 proto->slab == NULL ? "no" : "yes", 4067 module_name(proto->owner), 4068 proto_method_implemented(proto->close), 4069 proto_method_implemented(proto->connect), 4070 proto_method_implemented(proto->disconnect), 4071 proto_method_implemented(proto->accept), 4072 proto_method_implemented(proto->ioctl), 4073 proto_method_implemented(proto->init), 4074 proto_method_implemented(proto->destroy), 4075 proto_method_implemented(proto->shutdown), 4076 proto_method_implemented(proto->setsockopt), 4077 proto_method_implemented(proto->getsockopt), 4078 proto_method_implemented(proto->sendmsg), 4079 proto_method_implemented(proto->recvmsg), 4080 proto_method_implemented(proto->bind), 4081 proto_method_implemented(proto->backlog_rcv), 4082 proto_method_implemented(proto->hash), 4083 proto_method_implemented(proto->unhash), 4084 proto_method_implemented(proto->get_port), 4085 proto_method_implemented(proto->enter_memory_pressure)); 4086 } 4087 4088 static int proto_seq_show(struct seq_file *seq, void *v) 4089 { 4090 if (v == &proto_list) 4091 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 4092 "protocol", 4093 "size", 4094 "sockets", 4095 "memory", 4096 "press", 4097 "maxhdr", 4098 "slab", 4099 "module", 4100 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n"); 4101 else 4102 proto_seq_printf(seq, list_entry(v, struct proto, node)); 4103 return 0; 4104 } 4105 4106 static const struct seq_operations proto_seq_ops = { 4107 .start = proto_seq_start, 4108 .next = proto_seq_next, 4109 .stop = proto_seq_stop, 4110 .show = proto_seq_show, 4111 }; 4112 4113 static __net_init int proto_init_net(struct net *net) 4114 { 4115 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops, 4116 sizeof(struct seq_net_private))) 4117 return -ENOMEM; 4118 4119 return 0; 4120 } 4121 4122 static __net_exit void proto_exit_net(struct net *net) 4123 { 4124 remove_proc_entry("protocols", net->proc_net); 4125 } 4126 4127 4128 static __net_initdata struct pernet_operations proto_net_ops = { 4129 .init = proto_init_net, 4130 .exit = proto_exit_net, 4131 }; 4132 4133 static int __init proto_init(void) 4134 { 4135 return register_pernet_subsys(&proto_net_ops); 4136 } 4137 4138 subsys_initcall(proto_init); 4139 4140 #endif /* PROC_FS */ 4141 4142 #ifdef CONFIG_NET_RX_BUSY_POLL 4143 bool sk_busy_loop_end(void *p, unsigned long start_time) 4144 { 4145 struct sock *sk = p; 4146 4147 if (!skb_queue_empty_lockless(&sk->sk_receive_queue)) 4148 return true; 4149 4150 if (sk_is_udp(sk) && 4151 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue)) 4152 return true; 4153 4154 return sk_busy_loop_timeout(sk, start_time); 4155 } 4156 EXPORT_SYMBOL(sk_busy_loop_end); 4157 #endif /* CONFIG_NET_RX_BUSY_POLL */ 4158 4159 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len) 4160 { 4161 if (!sk->sk_prot->bind_add) 4162 return -EOPNOTSUPP; 4163 return sk->sk_prot->bind_add(sk, addr, addr_len); 4164 } 4165 EXPORT_SYMBOL(sock_bind_add); 4166 4167 /* Copy 'size' bytes from userspace and return `size` back to userspace */ 4168 int sock_ioctl_inout(struct sock *sk, unsigned int cmd, 4169 void __user *arg, void *karg, size_t size) 4170 { 4171 int ret; 4172 4173 if (copy_from_user(karg, arg, size)) 4174 return -EFAULT; 4175 4176 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg); 4177 if (ret) 4178 return ret; 4179 4180 if (copy_to_user(arg, karg, size)) 4181 return -EFAULT; 4182 4183 return 0; 4184 } 4185 EXPORT_SYMBOL(sock_ioctl_inout); 4186 4187 /* This is the most common ioctl prep function, where the result (4 bytes) is 4188 * copied back to userspace if the ioctl() returns successfully. No input is 4189 * copied from userspace as input argument. 4190 */ 4191 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg) 4192 { 4193 int ret, karg = 0; 4194 4195 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg); 4196 if (ret) 4197 return ret; 4198 4199 return put_user(karg, (int __user *)arg); 4200 } 4201 4202 /* A wrapper around sock ioctls, which copies the data from userspace 4203 * (depending on the protocol/ioctl), and copies back the result to userspace. 4204 * The main motivation for this function is to pass kernel memory to the 4205 * protocol ioctl callbacks, instead of userspace memory. 4206 */ 4207 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg) 4208 { 4209 int rc = 1; 4210 4211 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET) 4212 rc = ipmr_sk_ioctl(sk, cmd, arg); 4213 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6) 4214 rc = ip6mr_sk_ioctl(sk, cmd, arg); 4215 else if (sk_is_phonet(sk)) 4216 rc = phonet_sk_ioctl(sk, cmd, arg); 4217 4218 /* If ioctl was processed, returns its value */ 4219 if (rc <= 0) 4220 return rc; 4221 4222 /* Otherwise call the default handler */ 4223 return sock_ioctl_out(sk, cmd, arg); 4224 } 4225 EXPORT_SYMBOL(sk_ioctl); 4226