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 <linux/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 <linux/skbuff_ref.h> 128 #include <net/net_namespace.h> 129 #include <net/request_sock.h> 130 #include <net/sock.h> 131 #include <net/proto_memory.h> 132 #include <linux/net_tstamp.h> 133 #include <net/xfrm.h> 134 #include <linux/ipsec.h> 135 #include <net/cls_cgroup.h> 136 #include <net/netprio_cgroup.h> 137 #include <linux/sock_diag.h> 138 139 #include <linux/filter.h> 140 #include <net/sock_reuseport.h> 141 #include <net/bpf_sk_storage.h> 142 143 #include <trace/events/sock.h> 144 145 #include <net/tcp.h> 146 #include <net/busy_poll.h> 147 #include <net/phonet/phonet.h> 148 149 #include <linux/ethtool.h> 150 151 #include "dev.h" 152 153 static DEFINE_MUTEX(proto_list_mutex); 154 static LIST_HEAD(proto_list); 155 156 static void sock_def_write_space_wfree(struct sock *sk); 157 static void sock_def_write_space(struct sock *sk); 158 159 /** 160 * sk_ns_capable - General socket capability test 161 * @sk: Socket to use a capability on or through 162 * @user_ns: The user namespace of the capability to use 163 * @cap: The capability to use 164 * 165 * Test to see if the opener of the socket had when the socket was 166 * created and the current process has the capability @cap in the user 167 * namespace @user_ns. 168 */ 169 bool sk_ns_capable(const struct sock *sk, 170 struct user_namespace *user_ns, int cap) 171 { 172 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 173 ns_capable(user_ns, cap); 174 } 175 EXPORT_SYMBOL(sk_ns_capable); 176 177 /** 178 * sk_capable - Socket global capability test 179 * @sk: Socket to use a capability on or through 180 * @cap: The global capability to use 181 * 182 * Test to see if the opener of the socket had when the socket was 183 * created and the current process has the capability @cap in all user 184 * namespaces. 185 */ 186 bool sk_capable(const struct sock *sk, int cap) 187 { 188 return sk_ns_capable(sk, &init_user_ns, cap); 189 } 190 EXPORT_SYMBOL(sk_capable); 191 192 /** 193 * sk_net_capable - Network namespace socket capability test 194 * @sk: Socket to use a capability on or through 195 * @cap: The capability to use 196 * 197 * Test to see if the opener of the socket had when the socket was created 198 * and the current process has the capability @cap over the network namespace 199 * the socket is a member of. 200 */ 201 bool sk_net_capable(const struct sock *sk, int cap) 202 { 203 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 204 } 205 EXPORT_SYMBOL(sk_net_capable); 206 207 /* 208 * Each address family might have different locking rules, so we have 209 * one slock key per address family and separate keys for internal and 210 * userspace sockets. 211 */ 212 static struct lock_class_key af_family_keys[AF_MAX]; 213 static struct lock_class_key af_family_kern_keys[AF_MAX]; 214 static struct lock_class_key af_family_slock_keys[AF_MAX]; 215 static struct lock_class_key af_family_kern_slock_keys[AF_MAX]; 216 217 /* 218 * Make lock validator output more readable. (we pre-construct these 219 * strings build-time, so that runtime initialization of socket 220 * locks is fast): 221 */ 222 223 #define _sock_locks(x) \ 224 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \ 225 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \ 226 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \ 227 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \ 228 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \ 229 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \ 230 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \ 231 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \ 232 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \ 233 x "27" , x "28" , x "AF_CAN" , \ 234 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \ 235 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \ 236 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \ 237 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \ 238 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \ 239 x "AF_MCTP" , \ 240 x "AF_MAX" 241 242 static const char *const af_family_key_strings[AF_MAX+1] = { 243 _sock_locks("sk_lock-") 244 }; 245 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 246 _sock_locks("slock-") 247 }; 248 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 249 _sock_locks("clock-") 250 }; 251 252 static const char *const af_family_kern_key_strings[AF_MAX+1] = { 253 _sock_locks("k-sk_lock-") 254 }; 255 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = { 256 _sock_locks("k-slock-") 257 }; 258 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = { 259 _sock_locks("k-clock-") 260 }; 261 static const char *const af_family_rlock_key_strings[AF_MAX+1] = { 262 _sock_locks("rlock-") 263 }; 264 static const char *const af_family_wlock_key_strings[AF_MAX+1] = { 265 _sock_locks("wlock-") 266 }; 267 static const char *const af_family_elock_key_strings[AF_MAX+1] = { 268 _sock_locks("elock-") 269 }; 270 271 /* 272 * sk_callback_lock and sk queues locking rules are per-address-family, 273 * so split the lock classes by using a per-AF key: 274 */ 275 static struct lock_class_key af_callback_keys[AF_MAX]; 276 static struct lock_class_key af_rlock_keys[AF_MAX]; 277 static struct lock_class_key af_wlock_keys[AF_MAX]; 278 static struct lock_class_key af_elock_keys[AF_MAX]; 279 static struct lock_class_key af_kern_callback_keys[AF_MAX]; 280 281 /* Run time adjustable parameters. */ 282 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 283 EXPORT_SYMBOL(sysctl_wmem_max); 284 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 285 EXPORT_SYMBOL(sysctl_rmem_max); 286 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 287 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 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 sk_set_prio_allowed(const struct sock *sk, int val) 458 { 459 return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) || 460 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) || 461 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)); 462 } 463 464 static bool sock_needs_netstamp(const struct sock *sk) 465 { 466 switch (sk->sk_family) { 467 case AF_UNSPEC: 468 case AF_UNIX: 469 return false; 470 default: 471 return true; 472 } 473 } 474 475 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 476 { 477 if (sk->sk_flags & flags) { 478 sk->sk_flags &= ~flags; 479 if (sock_needs_netstamp(sk) && 480 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 481 net_disable_timestamp(); 482 } 483 } 484 485 486 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 487 { 488 unsigned long flags; 489 struct sk_buff_head *list = &sk->sk_receive_queue; 490 491 if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) { 492 atomic_inc(&sk->sk_drops); 493 trace_sock_rcvqueue_full(sk, skb); 494 return -ENOMEM; 495 } 496 497 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 498 atomic_inc(&sk->sk_drops); 499 return -ENOBUFS; 500 } 501 502 skb->dev = NULL; 503 skb_set_owner_r(skb, sk); 504 505 /* we escape from rcu protected region, make sure we dont leak 506 * a norefcounted dst 507 */ 508 skb_dst_force(skb); 509 510 spin_lock_irqsave(&list->lock, flags); 511 sock_skb_set_dropcount(sk, skb); 512 __skb_queue_tail(list, skb); 513 spin_unlock_irqrestore(&list->lock, flags); 514 515 if (!sock_flag(sk, SOCK_DEAD)) 516 sk->sk_data_ready(sk); 517 return 0; 518 } 519 EXPORT_SYMBOL(__sock_queue_rcv_skb); 520 521 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 522 enum skb_drop_reason *reason) 523 { 524 enum skb_drop_reason drop_reason; 525 int err; 526 527 err = sk_filter(sk, skb); 528 if (err) { 529 drop_reason = SKB_DROP_REASON_SOCKET_FILTER; 530 goto out; 531 } 532 err = __sock_queue_rcv_skb(sk, skb); 533 switch (err) { 534 case -ENOMEM: 535 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF; 536 break; 537 case -ENOBUFS: 538 drop_reason = SKB_DROP_REASON_PROTO_MEM; 539 break; 540 default: 541 drop_reason = SKB_NOT_DROPPED_YET; 542 break; 543 } 544 out: 545 if (reason) 546 *reason = drop_reason; 547 return err; 548 } 549 EXPORT_SYMBOL(sock_queue_rcv_skb_reason); 550 551 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 552 const int nested, unsigned int trim_cap, bool refcounted) 553 { 554 int rc = NET_RX_SUCCESS; 555 556 if (sk_filter_trim_cap(sk, skb, trim_cap)) 557 goto discard_and_relse; 558 559 skb->dev = NULL; 560 561 if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) { 562 atomic_inc(&sk->sk_drops); 563 goto discard_and_relse; 564 } 565 if (nested) 566 bh_lock_sock_nested(sk); 567 else 568 bh_lock_sock(sk); 569 if (!sock_owned_by_user(sk)) { 570 /* 571 * trylock + unlock semantics: 572 */ 573 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 574 575 rc = sk_backlog_rcv(sk, skb); 576 577 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 578 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) { 579 bh_unlock_sock(sk); 580 atomic_inc(&sk->sk_drops); 581 goto discard_and_relse; 582 } 583 584 bh_unlock_sock(sk); 585 out: 586 if (refcounted) 587 sock_put(sk); 588 return rc; 589 discard_and_relse: 590 kfree_skb(skb); 591 goto out; 592 } 593 EXPORT_SYMBOL(__sk_receive_skb); 594 595 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *, 596 u32)); 597 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *, 598 u32)); 599 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 600 { 601 struct dst_entry *dst = __sk_dst_get(sk); 602 603 if (dst && dst->obsolete && 604 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check, 605 dst, cookie) == NULL) { 606 sk_tx_queue_clear(sk); 607 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 608 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 609 dst_release(dst); 610 return NULL; 611 } 612 613 return dst; 614 } 615 EXPORT_SYMBOL(__sk_dst_check); 616 617 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 618 { 619 struct dst_entry *dst = sk_dst_get(sk); 620 621 if (dst && dst->obsolete && 622 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check, 623 dst, cookie) == NULL) { 624 sk_dst_reset(sk); 625 dst_release(dst); 626 return NULL; 627 } 628 629 return dst; 630 } 631 EXPORT_SYMBOL(sk_dst_check); 632 633 static int sock_bindtoindex_locked(struct sock *sk, int ifindex) 634 { 635 int ret = -ENOPROTOOPT; 636 #ifdef CONFIG_NETDEVICES 637 struct net *net = sock_net(sk); 638 639 /* Sorry... */ 640 ret = -EPERM; 641 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW)) 642 goto out; 643 644 ret = -EINVAL; 645 if (ifindex < 0) 646 goto out; 647 648 /* Paired with all READ_ONCE() done locklessly. */ 649 WRITE_ONCE(sk->sk_bound_dev_if, ifindex); 650 651 if (sk->sk_prot->rehash) 652 sk->sk_prot->rehash(sk); 653 sk_dst_reset(sk); 654 655 ret = 0; 656 657 out: 658 #endif 659 660 return ret; 661 } 662 663 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk) 664 { 665 int ret; 666 667 if (lock_sk) 668 lock_sock(sk); 669 ret = sock_bindtoindex_locked(sk, ifindex); 670 if (lock_sk) 671 release_sock(sk); 672 673 return ret; 674 } 675 EXPORT_SYMBOL(sock_bindtoindex); 676 677 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen) 678 { 679 int ret = -ENOPROTOOPT; 680 #ifdef CONFIG_NETDEVICES 681 struct net *net = sock_net(sk); 682 char devname[IFNAMSIZ]; 683 int index; 684 685 ret = -EINVAL; 686 if (optlen < 0) 687 goto out; 688 689 /* Bind this socket to a particular device like "eth0", 690 * as specified in the passed interface name. If the 691 * name is "" or the option length is zero the socket 692 * is not bound. 693 */ 694 if (optlen > IFNAMSIZ - 1) 695 optlen = IFNAMSIZ - 1; 696 memset(devname, 0, sizeof(devname)); 697 698 ret = -EFAULT; 699 if (copy_from_sockptr(devname, optval, optlen)) 700 goto out; 701 702 index = 0; 703 if (devname[0] != '\0') { 704 struct net_device *dev; 705 706 rcu_read_lock(); 707 dev = dev_get_by_name_rcu(net, devname); 708 if (dev) 709 index = dev->ifindex; 710 rcu_read_unlock(); 711 ret = -ENODEV; 712 if (!dev) 713 goto out; 714 } 715 716 sockopt_lock_sock(sk); 717 ret = sock_bindtoindex_locked(sk, index); 718 sockopt_release_sock(sk); 719 out: 720 #endif 721 722 return ret; 723 } 724 725 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval, 726 sockptr_t optlen, int len) 727 { 728 int ret = -ENOPROTOOPT; 729 #ifdef CONFIG_NETDEVICES 730 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 731 struct net *net = sock_net(sk); 732 char devname[IFNAMSIZ]; 733 734 if (bound_dev_if == 0) { 735 len = 0; 736 goto zero; 737 } 738 739 ret = -EINVAL; 740 if (len < IFNAMSIZ) 741 goto out; 742 743 ret = netdev_get_name(net, devname, bound_dev_if); 744 if (ret) 745 goto out; 746 747 len = strlen(devname) + 1; 748 749 ret = -EFAULT; 750 if (copy_to_sockptr(optval, devname, len)) 751 goto out; 752 753 zero: 754 ret = -EFAULT; 755 if (copy_to_sockptr(optlen, &len, sizeof(int))) 756 goto out; 757 758 ret = 0; 759 760 out: 761 #endif 762 763 return ret; 764 } 765 766 bool sk_mc_loop(const struct sock *sk) 767 { 768 if (dev_recursion_level()) 769 return false; 770 if (!sk) 771 return true; 772 /* IPV6_ADDRFORM can change sk->sk_family under us. */ 773 switch (READ_ONCE(sk->sk_family)) { 774 case AF_INET: 775 return inet_test_bit(MC_LOOP, sk); 776 #if IS_ENABLED(CONFIG_IPV6) 777 case AF_INET6: 778 return inet6_test_bit(MC6_LOOP, sk); 779 #endif 780 } 781 WARN_ON_ONCE(1); 782 return true; 783 } 784 EXPORT_SYMBOL(sk_mc_loop); 785 786 void sock_set_reuseaddr(struct sock *sk) 787 { 788 lock_sock(sk); 789 sk->sk_reuse = SK_CAN_REUSE; 790 release_sock(sk); 791 } 792 EXPORT_SYMBOL(sock_set_reuseaddr); 793 794 void sock_set_reuseport(struct sock *sk) 795 { 796 lock_sock(sk); 797 sk->sk_reuseport = true; 798 release_sock(sk); 799 } 800 EXPORT_SYMBOL(sock_set_reuseport); 801 802 void sock_no_linger(struct sock *sk) 803 { 804 lock_sock(sk); 805 WRITE_ONCE(sk->sk_lingertime, 0); 806 sock_set_flag(sk, SOCK_LINGER); 807 release_sock(sk); 808 } 809 EXPORT_SYMBOL(sock_no_linger); 810 811 void sock_set_priority(struct sock *sk, u32 priority) 812 { 813 WRITE_ONCE(sk->sk_priority, priority); 814 } 815 EXPORT_SYMBOL(sock_set_priority); 816 817 void sock_set_sndtimeo(struct sock *sk, s64 secs) 818 { 819 lock_sock(sk); 820 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1) 821 WRITE_ONCE(sk->sk_sndtimeo, secs * HZ); 822 else 823 WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT); 824 release_sock(sk); 825 } 826 EXPORT_SYMBOL(sock_set_sndtimeo); 827 828 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns) 829 { 830 sock_valbool_flag(sk, SOCK_RCVTSTAMP, val); 831 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns); 832 if (val) { 833 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new); 834 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 835 } 836 } 837 838 void sock_enable_timestamps(struct sock *sk) 839 { 840 lock_sock(sk); 841 __sock_set_timestamps(sk, true, false, true); 842 release_sock(sk); 843 } 844 EXPORT_SYMBOL(sock_enable_timestamps); 845 846 void sock_set_timestamp(struct sock *sk, int optname, bool valbool) 847 { 848 switch (optname) { 849 case SO_TIMESTAMP_OLD: 850 __sock_set_timestamps(sk, valbool, false, false); 851 break; 852 case SO_TIMESTAMP_NEW: 853 __sock_set_timestamps(sk, valbool, true, false); 854 break; 855 case SO_TIMESTAMPNS_OLD: 856 __sock_set_timestamps(sk, valbool, false, true); 857 break; 858 case SO_TIMESTAMPNS_NEW: 859 __sock_set_timestamps(sk, valbool, true, true); 860 break; 861 } 862 } 863 864 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index) 865 { 866 struct net *net = sock_net(sk); 867 struct net_device *dev = NULL; 868 bool match = false; 869 int *vclock_index; 870 int i, num; 871 872 if (sk->sk_bound_dev_if) 873 dev = dev_get_by_index(net, sk->sk_bound_dev_if); 874 875 if (!dev) { 876 pr_err("%s: sock not bind to device\n", __func__); 877 return -EOPNOTSUPP; 878 } 879 880 num = ethtool_get_phc_vclocks(dev, &vclock_index); 881 dev_put(dev); 882 883 for (i = 0; i < num; i++) { 884 if (*(vclock_index + i) == phc_index) { 885 match = true; 886 break; 887 } 888 } 889 890 if (num > 0) 891 kfree(vclock_index); 892 893 if (!match) 894 return -EINVAL; 895 896 WRITE_ONCE(sk->sk_bind_phc, phc_index); 897 898 return 0; 899 } 900 901 int sock_set_timestamping(struct sock *sk, int optname, 902 struct so_timestamping timestamping) 903 { 904 int val = timestamping.flags; 905 int ret; 906 907 if (val & ~SOF_TIMESTAMPING_MASK) 908 return -EINVAL; 909 910 if (val & SOF_TIMESTAMPING_OPT_ID_TCP && 911 !(val & SOF_TIMESTAMPING_OPT_ID)) 912 return -EINVAL; 913 914 if (val & SOF_TIMESTAMPING_OPT_ID && 915 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 916 if (sk_is_tcp(sk)) { 917 if ((1 << sk->sk_state) & 918 (TCPF_CLOSE | TCPF_LISTEN)) 919 return -EINVAL; 920 if (val & SOF_TIMESTAMPING_OPT_ID_TCP) 921 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq); 922 else 923 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una); 924 } else { 925 atomic_set(&sk->sk_tskey, 0); 926 } 927 } 928 929 if (val & SOF_TIMESTAMPING_OPT_STATS && 930 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) 931 return -EINVAL; 932 933 if (val & SOF_TIMESTAMPING_BIND_PHC) { 934 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc); 935 if (ret) 936 return ret; 937 } 938 939 WRITE_ONCE(sk->sk_tsflags, val); 940 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW); 941 942 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 943 sock_enable_timestamp(sk, 944 SOCK_TIMESTAMPING_RX_SOFTWARE); 945 else 946 sock_disable_timestamp(sk, 947 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 948 return 0; 949 } 950 951 void sock_set_keepalive(struct sock *sk) 952 { 953 lock_sock(sk); 954 if (sk->sk_prot->keepalive) 955 sk->sk_prot->keepalive(sk, true); 956 sock_valbool_flag(sk, SOCK_KEEPOPEN, true); 957 release_sock(sk); 958 } 959 EXPORT_SYMBOL(sock_set_keepalive); 960 961 static void __sock_set_rcvbuf(struct sock *sk, int val) 962 { 963 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it 964 * as a negative value. 965 */ 966 val = min_t(int, val, INT_MAX / 2); 967 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 968 969 /* We double it on the way in to account for "struct sk_buff" etc. 970 * overhead. Applications assume that the SO_RCVBUF setting they make 971 * will allow that much actual data to be received on that socket. 972 * 973 * Applications are unaware that "struct sk_buff" and other overheads 974 * allocate from the receive buffer during socket buffer allocation. 975 * 976 * And after considering the possible alternatives, returning the value 977 * we actually used in getsockopt is the most desirable behavior. 978 */ 979 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF)); 980 } 981 982 void sock_set_rcvbuf(struct sock *sk, int val) 983 { 984 lock_sock(sk); 985 __sock_set_rcvbuf(sk, val); 986 release_sock(sk); 987 } 988 EXPORT_SYMBOL(sock_set_rcvbuf); 989 990 static void __sock_set_mark(struct sock *sk, u32 val) 991 { 992 if (val != sk->sk_mark) { 993 WRITE_ONCE(sk->sk_mark, val); 994 sk_dst_reset(sk); 995 } 996 } 997 998 void sock_set_mark(struct sock *sk, u32 val) 999 { 1000 lock_sock(sk); 1001 __sock_set_mark(sk, val); 1002 release_sock(sk); 1003 } 1004 EXPORT_SYMBOL(sock_set_mark); 1005 1006 static void sock_release_reserved_memory(struct sock *sk, int bytes) 1007 { 1008 /* Round down bytes to multiple of pages */ 1009 bytes = round_down(bytes, PAGE_SIZE); 1010 1011 WARN_ON(bytes > sk->sk_reserved_mem); 1012 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes); 1013 sk_mem_reclaim(sk); 1014 } 1015 1016 static int sock_reserve_memory(struct sock *sk, int bytes) 1017 { 1018 long allocated; 1019 bool charged; 1020 int pages; 1021 1022 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk)) 1023 return -EOPNOTSUPP; 1024 1025 if (!bytes) 1026 return 0; 1027 1028 pages = sk_mem_pages(bytes); 1029 1030 /* pre-charge to memcg */ 1031 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages, 1032 GFP_KERNEL | __GFP_RETRY_MAYFAIL); 1033 if (!charged) 1034 return -ENOMEM; 1035 1036 /* pre-charge to forward_alloc */ 1037 sk_memory_allocated_add(sk, pages); 1038 allocated = sk_memory_allocated(sk); 1039 /* If the system goes into memory pressure with this 1040 * precharge, give up and return error. 1041 */ 1042 if (allocated > sk_prot_mem_limits(sk, 1)) { 1043 sk_memory_allocated_sub(sk, pages); 1044 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages); 1045 return -ENOMEM; 1046 } 1047 sk_forward_alloc_add(sk, pages << PAGE_SHIFT); 1048 1049 WRITE_ONCE(sk->sk_reserved_mem, 1050 sk->sk_reserved_mem + (pages << PAGE_SHIFT)); 1051 1052 return 0; 1053 } 1054 1055 #ifdef CONFIG_PAGE_POOL 1056 1057 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED 1058 * in 1 syscall. The limit exists to limit the amount of memory the kernel 1059 * allocates to copy these tokens, and to prevent looping over the frags for 1060 * too long. 1061 */ 1062 #define MAX_DONTNEED_TOKENS 128 1063 #define MAX_DONTNEED_FRAGS 1024 1064 1065 static noinline_for_stack int 1066 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen) 1067 { 1068 unsigned int num_tokens, i, j, k, netmem_num = 0; 1069 struct dmabuf_token *tokens; 1070 int ret = 0, num_frags = 0; 1071 netmem_ref netmems[16]; 1072 1073 if (!sk_is_tcp(sk)) 1074 return -EBADF; 1075 1076 if (optlen % sizeof(*tokens) || 1077 optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS) 1078 return -EINVAL; 1079 1080 num_tokens = optlen / sizeof(*tokens); 1081 tokens = kvmalloc_array(num_tokens, sizeof(*tokens), GFP_KERNEL); 1082 if (!tokens) 1083 return -ENOMEM; 1084 1085 if (copy_from_sockptr(tokens, optval, optlen)) { 1086 kvfree(tokens); 1087 return -EFAULT; 1088 } 1089 1090 xa_lock_bh(&sk->sk_user_frags); 1091 for (i = 0; i < num_tokens; i++) { 1092 for (j = 0; j < tokens[i].token_count; j++) { 1093 if (++num_frags > MAX_DONTNEED_FRAGS) 1094 goto frag_limit_reached; 1095 1096 netmem_ref netmem = (__force netmem_ref)__xa_erase( 1097 &sk->sk_user_frags, tokens[i].token_start + j); 1098 1099 if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem))) 1100 continue; 1101 1102 netmems[netmem_num++] = netmem; 1103 if (netmem_num == ARRAY_SIZE(netmems)) { 1104 xa_unlock_bh(&sk->sk_user_frags); 1105 for (k = 0; k < netmem_num; k++) 1106 WARN_ON_ONCE(!napi_pp_put_page(netmems[k])); 1107 netmem_num = 0; 1108 xa_lock_bh(&sk->sk_user_frags); 1109 } 1110 ret++; 1111 } 1112 } 1113 1114 frag_limit_reached: 1115 xa_unlock_bh(&sk->sk_user_frags); 1116 for (k = 0; k < netmem_num; k++) 1117 WARN_ON_ONCE(!napi_pp_put_page(netmems[k])); 1118 1119 kvfree(tokens); 1120 return ret; 1121 } 1122 #endif 1123 1124 void sockopt_lock_sock(struct sock *sk) 1125 { 1126 /* When current->bpf_ctx is set, the setsockopt is called from 1127 * a bpf prog. bpf has ensured the sk lock has been 1128 * acquired before calling setsockopt(). 1129 */ 1130 if (has_current_bpf_ctx()) 1131 return; 1132 1133 lock_sock(sk); 1134 } 1135 EXPORT_SYMBOL(sockopt_lock_sock); 1136 1137 void sockopt_release_sock(struct sock *sk) 1138 { 1139 if (has_current_bpf_ctx()) 1140 return; 1141 1142 release_sock(sk); 1143 } 1144 EXPORT_SYMBOL(sockopt_release_sock); 1145 1146 bool sockopt_ns_capable(struct user_namespace *ns, int cap) 1147 { 1148 return has_current_bpf_ctx() || ns_capable(ns, cap); 1149 } 1150 EXPORT_SYMBOL(sockopt_ns_capable); 1151 1152 bool sockopt_capable(int cap) 1153 { 1154 return has_current_bpf_ctx() || capable(cap); 1155 } 1156 EXPORT_SYMBOL(sockopt_capable); 1157 1158 static int sockopt_validate_clockid(__kernel_clockid_t value) 1159 { 1160 switch (value) { 1161 case CLOCK_REALTIME: 1162 case CLOCK_MONOTONIC: 1163 case CLOCK_TAI: 1164 return 0; 1165 } 1166 return -EINVAL; 1167 } 1168 1169 /* 1170 * This is meant for all protocols to use and covers goings on 1171 * at the socket level. Everything here is generic. 1172 */ 1173 1174 int sk_setsockopt(struct sock *sk, int level, int optname, 1175 sockptr_t optval, unsigned int optlen) 1176 { 1177 struct so_timestamping timestamping; 1178 struct socket *sock = sk->sk_socket; 1179 struct sock_txtime sk_txtime; 1180 int val; 1181 int valbool; 1182 struct linger ling; 1183 int ret = 0; 1184 1185 /* 1186 * Options without arguments 1187 */ 1188 1189 if (optname == SO_BINDTODEVICE) 1190 return sock_setbindtodevice(sk, optval, optlen); 1191 1192 if (optlen < sizeof(int)) 1193 return -EINVAL; 1194 1195 if (copy_from_sockptr(&val, optval, sizeof(val))) 1196 return -EFAULT; 1197 1198 valbool = val ? 1 : 0; 1199 1200 /* handle options which do not require locking the socket. */ 1201 switch (optname) { 1202 case SO_PRIORITY: 1203 if (sk_set_prio_allowed(sk, val)) { 1204 sock_set_priority(sk, val); 1205 return 0; 1206 } 1207 return -EPERM; 1208 case SO_PASSSEC: 1209 assign_bit(SOCK_PASSSEC, &sock->flags, valbool); 1210 return 0; 1211 case SO_PASSCRED: 1212 assign_bit(SOCK_PASSCRED, &sock->flags, valbool); 1213 return 0; 1214 case SO_PASSPIDFD: 1215 assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool); 1216 return 0; 1217 case SO_TYPE: 1218 case SO_PROTOCOL: 1219 case SO_DOMAIN: 1220 case SO_ERROR: 1221 return -ENOPROTOOPT; 1222 #ifdef CONFIG_NET_RX_BUSY_POLL 1223 case SO_BUSY_POLL: 1224 if (val < 0) 1225 return -EINVAL; 1226 WRITE_ONCE(sk->sk_ll_usec, val); 1227 return 0; 1228 case SO_PREFER_BUSY_POLL: 1229 if (valbool && !sockopt_capable(CAP_NET_ADMIN)) 1230 return -EPERM; 1231 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool); 1232 return 0; 1233 case SO_BUSY_POLL_BUDGET: 1234 if (val > READ_ONCE(sk->sk_busy_poll_budget) && 1235 !sockopt_capable(CAP_NET_ADMIN)) 1236 return -EPERM; 1237 if (val < 0 || val > U16_MAX) 1238 return -EINVAL; 1239 WRITE_ONCE(sk->sk_busy_poll_budget, val); 1240 return 0; 1241 #endif 1242 case SO_MAX_PACING_RATE: 1243 { 1244 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val; 1245 unsigned long pacing_rate; 1246 1247 if (sizeof(ulval) != sizeof(val) && 1248 optlen >= sizeof(ulval) && 1249 copy_from_sockptr(&ulval, optval, sizeof(ulval))) { 1250 return -EFAULT; 1251 } 1252 if (ulval != ~0UL) 1253 cmpxchg(&sk->sk_pacing_status, 1254 SK_PACING_NONE, 1255 SK_PACING_NEEDED); 1256 /* Pairs with READ_ONCE() from sk_getsockopt() */ 1257 WRITE_ONCE(sk->sk_max_pacing_rate, ulval); 1258 pacing_rate = READ_ONCE(sk->sk_pacing_rate); 1259 if (ulval < pacing_rate) 1260 WRITE_ONCE(sk->sk_pacing_rate, ulval); 1261 return 0; 1262 } 1263 case SO_TXREHASH: 1264 if (val < -1 || val > 1) 1265 return -EINVAL; 1266 if ((u8)val == SOCK_TXREHASH_DEFAULT) 1267 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash); 1268 /* Paired with READ_ONCE() in tcp_rtx_synack() 1269 * and sk_getsockopt(). 1270 */ 1271 WRITE_ONCE(sk->sk_txrehash, (u8)val); 1272 return 0; 1273 case SO_PEEK_OFF: 1274 { 1275 int (*set_peek_off)(struct sock *sk, int val); 1276 1277 set_peek_off = READ_ONCE(sock->ops)->set_peek_off; 1278 if (set_peek_off) 1279 ret = set_peek_off(sk, val); 1280 else 1281 ret = -EOPNOTSUPP; 1282 return ret; 1283 } 1284 #ifdef CONFIG_PAGE_POOL 1285 case SO_DEVMEM_DONTNEED: 1286 return sock_devmem_dontneed(sk, optval, optlen); 1287 #endif 1288 } 1289 1290 sockopt_lock_sock(sk); 1291 1292 switch (optname) { 1293 case SO_DEBUG: 1294 if (val && !sockopt_capable(CAP_NET_ADMIN)) 1295 ret = -EACCES; 1296 else 1297 sock_valbool_flag(sk, SOCK_DBG, valbool); 1298 break; 1299 case SO_REUSEADDR: 1300 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 1301 break; 1302 case SO_REUSEPORT: 1303 if (valbool && !sk_is_inet(sk)) 1304 ret = -EOPNOTSUPP; 1305 else 1306 sk->sk_reuseport = valbool; 1307 break; 1308 case SO_DONTROUTE: 1309 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 1310 sk_dst_reset(sk); 1311 break; 1312 case SO_BROADCAST: 1313 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 1314 break; 1315 case SO_SNDBUF: 1316 /* Don't error on this BSD doesn't and if you think 1317 * about it this is right. Otherwise apps have to 1318 * play 'guess the biggest size' games. RCVBUF/SNDBUF 1319 * are treated in BSD as hints 1320 */ 1321 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max)); 1322 set_sndbuf: 1323 /* Ensure val * 2 fits into an int, to prevent max_t() 1324 * from treating it as a negative value. 1325 */ 1326 val = min_t(int, val, INT_MAX / 2); 1327 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 1328 WRITE_ONCE(sk->sk_sndbuf, 1329 max_t(int, val * 2, SOCK_MIN_SNDBUF)); 1330 /* Wake up sending tasks if we upped the value. */ 1331 sk->sk_write_space(sk); 1332 break; 1333 1334 case SO_SNDBUFFORCE: 1335 if (!sockopt_capable(CAP_NET_ADMIN)) { 1336 ret = -EPERM; 1337 break; 1338 } 1339 1340 /* No negative values (to prevent underflow, as val will be 1341 * multiplied by 2). 1342 */ 1343 if (val < 0) 1344 val = 0; 1345 goto set_sndbuf; 1346 1347 case SO_RCVBUF: 1348 /* Don't error on this BSD doesn't and if you think 1349 * about it this is right. Otherwise apps have to 1350 * play 'guess the biggest size' games. RCVBUF/SNDBUF 1351 * are treated in BSD as hints 1352 */ 1353 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max))); 1354 break; 1355 1356 case SO_RCVBUFFORCE: 1357 if (!sockopt_capable(CAP_NET_ADMIN)) { 1358 ret = -EPERM; 1359 break; 1360 } 1361 1362 /* No negative values (to prevent underflow, as val will be 1363 * multiplied by 2). 1364 */ 1365 __sock_set_rcvbuf(sk, max(val, 0)); 1366 break; 1367 1368 case SO_KEEPALIVE: 1369 if (sk->sk_prot->keepalive) 1370 sk->sk_prot->keepalive(sk, valbool); 1371 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 1372 break; 1373 1374 case SO_OOBINLINE: 1375 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 1376 break; 1377 1378 case SO_NO_CHECK: 1379 sk->sk_no_check_tx = valbool; 1380 break; 1381 1382 case SO_LINGER: 1383 if (optlen < sizeof(ling)) { 1384 ret = -EINVAL; /* 1003.1g */ 1385 break; 1386 } 1387 if (copy_from_sockptr(&ling, optval, sizeof(ling))) { 1388 ret = -EFAULT; 1389 break; 1390 } 1391 if (!ling.l_onoff) { 1392 sock_reset_flag(sk, SOCK_LINGER); 1393 } else { 1394 unsigned long t_sec = ling.l_linger; 1395 1396 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ) 1397 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT); 1398 else 1399 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ); 1400 sock_set_flag(sk, SOCK_LINGER); 1401 } 1402 break; 1403 1404 case SO_BSDCOMPAT: 1405 break; 1406 1407 case SO_TIMESTAMP_OLD: 1408 case SO_TIMESTAMP_NEW: 1409 case SO_TIMESTAMPNS_OLD: 1410 case SO_TIMESTAMPNS_NEW: 1411 sock_set_timestamp(sk, optname, valbool); 1412 break; 1413 1414 case SO_TIMESTAMPING_NEW: 1415 case SO_TIMESTAMPING_OLD: 1416 if (optlen == sizeof(timestamping)) { 1417 if (copy_from_sockptr(×tamping, optval, 1418 sizeof(timestamping))) { 1419 ret = -EFAULT; 1420 break; 1421 } 1422 } else { 1423 memset(×tamping, 0, sizeof(timestamping)); 1424 timestamping.flags = val; 1425 } 1426 ret = sock_set_timestamping(sk, optname, timestamping); 1427 break; 1428 1429 case SO_RCVLOWAT: 1430 { 1431 int (*set_rcvlowat)(struct sock *sk, int val) = NULL; 1432 1433 if (val < 0) 1434 val = INT_MAX; 1435 if (sock) 1436 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat; 1437 if (set_rcvlowat) 1438 ret = set_rcvlowat(sk, val); 1439 else 1440 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 1441 break; 1442 } 1443 case SO_RCVTIMEO_OLD: 1444 case SO_RCVTIMEO_NEW: 1445 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, 1446 optlen, optname == SO_RCVTIMEO_OLD); 1447 break; 1448 1449 case SO_SNDTIMEO_OLD: 1450 case SO_SNDTIMEO_NEW: 1451 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, 1452 optlen, optname == SO_SNDTIMEO_OLD); 1453 break; 1454 1455 case SO_ATTACH_FILTER: { 1456 struct sock_fprog fprog; 1457 1458 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); 1459 if (!ret) 1460 ret = sk_attach_filter(&fprog, sk); 1461 break; 1462 } 1463 case SO_ATTACH_BPF: 1464 ret = -EINVAL; 1465 if (optlen == sizeof(u32)) { 1466 u32 ufd; 1467 1468 ret = -EFAULT; 1469 if (copy_from_sockptr(&ufd, optval, sizeof(ufd))) 1470 break; 1471 1472 ret = sk_attach_bpf(ufd, sk); 1473 } 1474 break; 1475 1476 case SO_ATTACH_REUSEPORT_CBPF: { 1477 struct sock_fprog fprog; 1478 1479 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); 1480 if (!ret) 1481 ret = sk_reuseport_attach_filter(&fprog, sk); 1482 break; 1483 } 1484 case SO_ATTACH_REUSEPORT_EBPF: 1485 ret = -EINVAL; 1486 if (optlen == sizeof(u32)) { 1487 u32 ufd; 1488 1489 ret = -EFAULT; 1490 if (copy_from_sockptr(&ufd, optval, sizeof(ufd))) 1491 break; 1492 1493 ret = sk_reuseport_attach_bpf(ufd, sk); 1494 } 1495 break; 1496 1497 case SO_DETACH_REUSEPORT_BPF: 1498 ret = reuseport_detach_prog(sk); 1499 break; 1500 1501 case SO_DETACH_FILTER: 1502 ret = sk_detach_filter(sk); 1503 break; 1504 1505 case SO_LOCK_FILTER: 1506 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 1507 ret = -EPERM; 1508 else 1509 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 1510 break; 1511 1512 case SO_MARK: 1513 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && 1514 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1515 ret = -EPERM; 1516 break; 1517 } 1518 1519 __sock_set_mark(sk, val); 1520 break; 1521 case SO_RCVMARK: 1522 sock_valbool_flag(sk, SOCK_RCVMARK, valbool); 1523 break; 1524 1525 case SO_RCVPRIORITY: 1526 sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool); 1527 break; 1528 1529 case SO_RXQ_OVFL: 1530 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 1531 break; 1532 1533 case SO_WIFI_STATUS: 1534 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 1535 break; 1536 1537 case SO_NOFCS: 1538 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 1539 break; 1540 1541 case SO_SELECT_ERR_QUEUE: 1542 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 1543 break; 1544 1545 1546 case SO_INCOMING_CPU: 1547 reuseport_update_incoming_cpu(sk, val); 1548 break; 1549 1550 case SO_CNX_ADVICE: 1551 if (val == 1) 1552 dst_negative_advice(sk); 1553 break; 1554 1555 case SO_ZEROCOPY: 1556 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) { 1557 if (!(sk_is_tcp(sk) || 1558 (sk->sk_type == SOCK_DGRAM && 1559 sk->sk_protocol == IPPROTO_UDP))) 1560 ret = -EOPNOTSUPP; 1561 } else if (sk->sk_family != PF_RDS) { 1562 ret = -EOPNOTSUPP; 1563 } 1564 if (!ret) { 1565 if (val < 0 || val > 1) 1566 ret = -EINVAL; 1567 else 1568 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); 1569 } 1570 break; 1571 1572 case SO_TXTIME: 1573 if (optlen != sizeof(struct sock_txtime)) { 1574 ret = -EINVAL; 1575 break; 1576 } else if (copy_from_sockptr(&sk_txtime, optval, 1577 sizeof(struct sock_txtime))) { 1578 ret = -EFAULT; 1579 break; 1580 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) { 1581 ret = -EINVAL; 1582 break; 1583 } 1584 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet 1585 * scheduler has enough safe guards. 1586 */ 1587 if (sk_txtime.clockid != CLOCK_MONOTONIC && 1588 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1589 ret = -EPERM; 1590 break; 1591 } 1592 1593 ret = sockopt_validate_clockid(sk_txtime.clockid); 1594 if (ret) 1595 break; 1596 1597 sock_valbool_flag(sk, SOCK_TXTIME, true); 1598 sk->sk_clockid = sk_txtime.clockid; 1599 sk->sk_txtime_deadline_mode = 1600 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE); 1601 sk->sk_txtime_report_errors = 1602 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS); 1603 break; 1604 1605 case SO_BINDTOIFINDEX: 1606 ret = sock_bindtoindex_locked(sk, val); 1607 break; 1608 1609 case SO_BUF_LOCK: 1610 if (val & ~SOCK_BUF_LOCK_MASK) { 1611 ret = -EINVAL; 1612 break; 1613 } 1614 sk->sk_userlocks = val | (sk->sk_userlocks & 1615 ~SOCK_BUF_LOCK_MASK); 1616 break; 1617 1618 case SO_RESERVE_MEM: 1619 { 1620 int delta; 1621 1622 if (val < 0) { 1623 ret = -EINVAL; 1624 break; 1625 } 1626 1627 delta = val - sk->sk_reserved_mem; 1628 if (delta < 0) 1629 sock_release_reserved_memory(sk, -delta); 1630 else 1631 ret = sock_reserve_memory(sk, delta); 1632 break; 1633 } 1634 1635 default: 1636 ret = -ENOPROTOOPT; 1637 break; 1638 } 1639 sockopt_release_sock(sk); 1640 return ret; 1641 } 1642 1643 int sock_setsockopt(struct socket *sock, int level, int optname, 1644 sockptr_t optval, unsigned int optlen) 1645 { 1646 return sk_setsockopt(sock->sk, level, optname, 1647 optval, optlen); 1648 } 1649 EXPORT_SYMBOL(sock_setsockopt); 1650 1651 static const struct cred *sk_get_peer_cred(struct sock *sk) 1652 { 1653 const struct cred *cred; 1654 1655 spin_lock(&sk->sk_peer_lock); 1656 cred = get_cred(sk->sk_peer_cred); 1657 spin_unlock(&sk->sk_peer_lock); 1658 1659 return cred; 1660 } 1661 1662 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1663 struct ucred *ucred) 1664 { 1665 ucred->pid = pid_vnr(pid); 1666 ucred->uid = ucred->gid = -1; 1667 if (cred) { 1668 struct user_namespace *current_ns = current_user_ns(); 1669 1670 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1671 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1672 } 1673 } 1674 1675 static int groups_to_user(sockptr_t dst, const struct group_info *src) 1676 { 1677 struct user_namespace *user_ns = current_user_ns(); 1678 int i; 1679 1680 for (i = 0; i < src->ngroups; i++) { 1681 gid_t gid = from_kgid_munged(user_ns, src->gid[i]); 1682 1683 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid))) 1684 return -EFAULT; 1685 } 1686 1687 return 0; 1688 } 1689 1690 int sk_getsockopt(struct sock *sk, int level, int optname, 1691 sockptr_t optval, sockptr_t optlen) 1692 { 1693 struct socket *sock = sk->sk_socket; 1694 1695 union { 1696 int val; 1697 u64 val64; 1698 unsigned long ulval; 1699 struct linger ling; 1700 struct old_timeval32 tm32; 1701 struct __kernel_old_timeval tm; 1702 struct __kernel_sock_timeval stm; 1703 struct sock_txtime txtime; 1704 struct so_timestamping timestamping; 1705 } v; 1706 1707 int lv = sizeof(int); 1708 int len; 1709 1710 if (copy_from_sockptr(&len, optlen, sizeof(int))) 1711 return -EFAULT; 1712 if (len < 0) 1713 return -EINVAL; 1714 1715 memset(&v, 0, sizeof(v)); 1716 1717 switch (optname) { 1718 case SO_DEBUG: 1719 v.val = sock_flag(sk, SOCK_DBG); 1720 break; 1721 1722 case SO_DONTROUTE: 1723 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1724 break; 1725 1726 case SO_BROADCAST: 1727 v.val = sock_flag(sk, SOCK_BROADCAST); 1728 break; 1729 1730 case SO_SNDBUF: 1731 v.val = READ_ONCE(sk->sk_sndbuf); 1732 break; 1733 1734 case SO_RCVBUF: 1735 v.val = READ_ONCE(sk->sk_rcvbuf); 1736 break; 1737 1738 case SO_REUSEADDR: 1739 v.val = sk->sk_reuse; 1740 break; 1741 1742 case SO_REUSEPORT: 1743 v.val = sk->sk_reuseport; 1744 break; 1745 1746 case SO_KEEPALIVE: 1747 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1748 break; 1749 1750 case SO_TYPE: 1751 v.val = sk->sk_type; 1752 break; 1753 1754 case SO_PROTOCOL: 1755 v.val = sk->sk_protocol; 1756 break; 1757 1758 case SO_DOMAIN: 1759 v.val = sk->sk_family; 1760 break; 1761 1762 case SO_ERROR: 1763 v.val = -sock_error(sk); 1764 if (v.val == 0) 1765 v.val = xchg(&sk->sk_err_soft, 0); 1766 break; 1767 1768 case SO_OOBINLINE: 1769 v.val = sock_flag(sk, SOCK_URGINLINE); 1770 break; 1771 1772 case SO_NO_CHECK: 1773 v.val = sk->sk_no_check_tx; 1774 break; 1775 1776 case SO_PRIORITY: 1777 v.val = READ_ONCE(sk->sk_priority); 1778 break; 1779 1780 case SO_LINGER: 1781 lv = sizeof(v.ling); 1782 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1783 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ; 1784 break; 1785 1786 case SO_BSDCOMPAT: 1787 break; 1788 1789 case SO_TIMESTAMP_OLD: 1790 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1791 !sock_flag(sk, SOCK_TSTAMP_NEW) && 1792 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1793 break; 1794 1795 case SO_TIMESTAMPNS_OLD: 1796 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW); 1797 break; 1798 1799 case SO_TIMESTAMP_NEW: 1800 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW); 1801 break; 1802 1803 case SO_TIMESTAMPNS_NEW: 1804 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW); 1805 break; 1806 1807 case SO_TIMESTAMPING_OLD: 1808 case SO_TIMESTAMPING_NEW: 1809 lv = sizeof(v.timestamping); 1810 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only 1811 * returning the flags when they were set through the same option. 1812 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD. 1813 */ 1814 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) { 1815 v.timestamping.flags = READ_ONCE(sk->sk_tsflags); 1816 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc); 1817 } 1818 break; 1819 1820 case SO_RCVTIMEO_OLD: 1821 case SO_RCVTIMEO_NEW: 1822 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v, 1823 SO_RCVTIMEO_OLD == optname); 1824 break; 1825 1826 case SO_SNDTIMEO_OLD: 1827 case SO_SNDTIMEO_NEW: 1828 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v, 1829 SO_SNDTIMEO_OLD == optname); 1830 break; 1831 1832 case SO_RCVLOWAT: 1833 v.val = READ_ONCE(sk->sk_rcvlowat); 1834 break; 1835 1836 case SO_SNDLOWAT: 1837 v.val = 1; 1838 break; 1839 1840 case SO_PASSCRED: 1841 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1842 break; 1843 1844 case SO_PASSPIDFD: 1845 v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags); 1846 break; 1847 1848 case SO_PEERCRED: 1849 { 1850 struct ucred peercred; 1851 if (len > sizeof(peercred)) 1852 len = sizeof(peercred); 1853 1854 spin_lock(&sk->sk_peer_lock); 1855 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1856 spin_unlock(&sk->sk_peer_lock); 1857 1858 if (copy_to_sockptr(optval, &peercred, len)) 1859 return -EFAULT; 1860 goto lenout; 1861 } 1862 1863 case SO_PEERPIDFD: 1864 { 1865 struct pid *peer_pid; 1866 struct file *pidfd_file = NULL; 1867 int pidfd; 1868 1869 if (len > sizeof(pidfd)) 1870 len = sizeof(pidfd); 1871 1872 spin_lock(&sk->sk_peer_lock); 1873 peer_pid = get_pid(sk->sk_peer_pid); 1874 spin_unlock(&sk->sk_peer_lock); 1875 1876 if (!peer_pid) 1877 return -ENODATA; 1878 1879 pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file); 1880 put_pid(peer_pid); 1881 if (pidfd < 0) 1882 return pidfd; 1883 1884 if (copy_to_sockptr(optval, &pidfd, len) || 1885 copy_to_sockptr(optlen, &len, sizeof(int))) { 1886 put_unused_fd(pidfd); 1887 fput(pidfd_file); 1888 1889 return -EFAULT; 1890 } 1891 1892 fd_install(pidfd, pidfd_file); 1893 return 0; 1894 } 1895 1896 case SO_PEERGROUPS: 1897 { 1898 const struct cred *cred; 1899 int ret, n; 1900 1901 cred = sk_get_peer_cred(sk); 1902 if (!cred) 1903 return -ENODATA; 1904 1905 n = cred->group_info->ngroups; 1906 if (len < n * sizeof(gid_t)) { 1907 len = n * sizeof(gid_t); 1908 put_cred(cred); 1909 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE; 1910 } 1911 len = n * sizeof(gid_t); 1912 1913 ret = groups_to_user(optval, cred->group_info); 1914 put_cred(cred); 1915 if (ret) 1916 return ret; 1917 goto lenout; 1918 } 1919 1920 case SO_PEERNAME: 1921 { 1922 struct sockaddr_storage address; 1923 1924 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2); 1925 if (lv < 0) 1926 return -ENOTCONN; 1927 if (lv < len) 1928 return -EINVAL; 1929 if (copy_to_sockptr(optval, &address, len)) 1930 return -EFAULT; 1931 goto lenout; 1932 } 1933 1934 /* Dubious BSD thing... Probably nobody even uses it, but 1935 * the UNIX standard wants it for whatever reason... -DaveM 1936 */ 1937 case SO_ACCEPTCONN: 1938 v.val = sk->sk_state == TCP_LISTEN; 1939 break; 1940 1941 case SO_PASSSEC: 1942 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1943 break; 1944 1945 case SO_PEERSEC: 1946 return security_socket_getpeersec_stream(sock, 1947 optval, optlen, len); 1948 1949 case SO_MARK: 1950 v.val = READ_ONCE(sk->sk_mark); 1951 break; 1952 1953 case SO_RCVMARK: 1954 v.val = sock_flag(sk, SOCK_RCVMARK); 1955 break; 1956 1957 case SO_RCVPRIORITY: 1958 v.val = sock_flag(sk, SOCK_RCVPRIORITY); 1959 break; 1960 1961 case SO_RXQ_OVFL: 1962 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1963 break; 1964 1965 case SO_WIFI_STATUS: 1966 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1967 break; 1968 1969 case SO_PEEK_OFF: 1970 if (!READ_ONCE(sock->ops)->set_peek_off) 1971 return -EOPNOTSUPP; 1972 1973 v.val = READ_ONCE(sk->sk_peek_off); 1974 break; 1975 case SO_NOFCS: 1976 v.val = sock_flag(sk, SOCK_NOFCS); 1977 break; 1978 1979 case SO_BINDTODEVICE: 1980 return sock_getbindtodevice(sk, optval, optlen, len); 1981 1982 case SO_GET_FILTER: 1983 len = sk_get_filter(sk, optval, len); 1984 if (len < 0) 1985 return len; 1986 1987 goto lenout; 1988 1989 case SO_LOCK_FILTER: 1990 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1991 break; 1992 1993 case SO_BPF_EXTENSIONS: 1994 v.val = bpf_tell_extensions(); 1995 break; 1996 1997 case SO_SELECT_ERR_QUEUE: 1998 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1999 break; 2000 2001 #ifdef CONFIG_NET_RX_BUSY_POLL 2002 case SO_BUSY_POLL: 2003 v.val = READ_ONCE(sk->sk_ll_usec); 2004 break; 2005 case SO_PREFER_BUSY_POLL: 2006 v.val = READ_ONCE(sk->sk_prefer_busy_poll); 2007 break; 2008 #endif 2009 2010 case SO_MAX_PACING_RATE: 2011 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */ 2012 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) { 2013 lv = sizeof(v.ulval); 2014 v.ulval = READ_ONCE(sk->sk_max_pacing_rate); 2015 } else { 2016 /* 32bit version */ 2017 v.val = min_t(unsigned long, ~0U, 2018 READ_ONCE(sk->sk_max_pacing_rate)); 2019 } 2020 break; 2021 2022 case SO_INCOMING_CPU: 2023 v.val = READ_ONCE(sk->sk_incoming_cpu); 2024 break; 2025 2026 case SO_MEMINFO: 2027 { 2028 u32 meminfo[SK_MEMINFO_VARS]; 2029 2030 sk_get_meminfo(sk, meminfo); 2031 2032 len = min_t(unsigned int, len, sizeof(meminfo)); 2033 if (copy_to_sockptr(optval, &meminfo, len)) 2034 return -EFAULT; 2035 2036 goto lenout; 2037 } 2038 2039 #ifdef CONFIG_NET_RX_BUSY_POLL 2040 case SO_INCOMING_NAPI_ID: 2041 v.val = READ_ONCE(sk->sk_napi_id); 2042 2043 /* aggregate non-NAPI IDs down to 0 */ 2044 if (v.val < MIN_NAPI_ID) 2045 v.val = 0; 2046 2047 break; 2048 #endif 2049 2050 case SO_COOKIE: 2051 lv = sizeof(u64); 2052 if (len < lv) 2053 return -EINVAL; 2054 v.val64 = sock_gen_cookie(sk); 2055 break; 2056 2057 case SO_ZEROCOPY: 2058 v.val = sock_flag(sk, SOCK_ZEROCOPY); 2059 break; 2060 2061 case SO_TXTIME: 2062 lv = sizeof(v.txtime); 2063 v.txtime.clockid = sk->sk_clockid; 2064 v.txtime.flags |= sk->sk_txtime_deadline_mode ? 2065 SOF_TXTIME_DEADLINE_MODE : 0; 2066 v.txtime.flags |= sk->sk_txtime_report_errors ? 2067 SOF_TXTIME_REPORT_ERRORS : 0; 2068 break; 2069 2070 case SO_BINDTOIFINDEX: 2071 v.val = READ_ONCE(sk->sk_bound_dev_if); 2072 break; 2073 2074 case SO_NETNS_COOKIE: 2075 lv = sizeof(u64); 2076 if (len != lv) 2077 return -EINVAL; 2078 v.val64 = sock_net(sk)->net_cookie; 2079 break; 2080 2081 case SO_BUF_LOCK: 2082 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK; 2083 break; 2084 2085 case SO_RESERVE_MEM: 2086 v.val = READ_ONCE(sk->sk_reserved_mem); 2087 break; 2088 2089 case SO_TXREHASH: 2090 /* Paired with WRITE_ONCE() in sk_setsockopt() */ 2091 v.val = READ_ONCE(sk->sk_txrehash); 2092 break; 2093 2094 default: 2095 /* We implement the SO_SNDLOWAT etc to not be settable 2096 * (1003.1g 7). 2097 */ 2098 return -ENOPROTOOPT; 2099 } 2100 2101 if (len > lv) 2102 len = lv; 2103 if (copy_to_sockptr(optval, &v, len)) 2104 return -EFAULT; 2105 lenout: 2106 if (copy_to_sockptr(optlen, &len, sizeof(int))) 2107 return -EFAULT; 2108 return 0; 2109 } 2110 2111 /* 2112 * Initialize an sk_lock. 2113 * 2114 * (We also register the sk_lock with the lock validator.) 2115 */ 2116 static inline void sock_lock_init(struct sock *sk) 2117 { 2118 if (sk->sk_kern_sock) 2119 sock_lock_init_class_and_name( 2120 sk, 2121 af_family_kern_slock_key_strings[sk->sk_family], 2122 af_family_kern_slock_keys + sk->sk_family, 2123 af_family_kern_key_strings[sk->sk_family], 2124 af_family_kern_keys + sk->sk_family); 2125 else 2126 sock_lock_init_class_and_name( 2127 sk, 2128 af_family_slock_key_strings[sk->sk_family], 2129 af_family_slock_keys + sk->sk_family, 2130 af_family_key_strings[sk->sk_family], 2131 af_family_keys + sk->sk_family); 2132 } 2133 2134 /* 2135 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 2136 * even temporarily, because of RCU lookups. sk_node should also be left as is. 2137 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 2138 */ 2139 static void sock_copy(struct sock *nsk, const struct sock *osk) 2140 { 2141 const struct proto *prot = READ_ONCE(osk->sk_prot); 2142 #ifdef CONFIG_SECURITY_NETWORK 2143 void *sptr = nsk->sk_security; 2144 #endif 2145 2146 /* If we move sk_tx_queue_mapping out of the private section, 2147 * we must check if sk_tx_queue_clear() is called after 2148 * sock_copy() in sk_clone_lock(). 2149 */ 2150 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) < 2151 offsetof(struct sock, sk_dontcopy_begin) || 2152 offsetof(struct sock, sk_tx_queue_mapping) >= 2153 offsetof(struct sock, sk_dontcopy_end)); 2154 2155 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 2156 2157 unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 2158 prot->obj_size - offsetof(struct sock, sk_dontcopy_end), 2159 /* alloc is larger than struct, see sk_prot_alloc() */); 2160 2161 #ifdef CONFIG_SECURITY_NETWORK 2162 nsk->sk_security = sptr; 2163 security_sk_clone(osk, nsk); 2164 #endif 2165 } 2166 2167 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 2168 int family) 2169 { 2170 struct sock *sk; 2171 struct kmem_cache *slab; 2172 2173 slab = prot->slab; 2174 if (slab != NULL) { 2175 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 2176 if (!sk) 2177 return sk; 2178 if (want_init_on_alloc(priority)) 2179 sk_prot_clear_nulls(sk, prot->obj_size); 2180 } else 2181 sk = kmalloc(prot->obj_size, priority); 2182 2183 if (sk != NULL) { 2184 if (security_sk_alloc(sk, family, priority)) 2185 goto out_free; 2186 2187 if (!try_module_get(prot->owner)) 2188 goto out_free_sec; 2189 } 2190 2191 return sk; 2192 2193 out_free_sec: 2194 security_sk_free(sk); 2195 out_free: 2196 if (slab != NULL) 2197 kmem_cache_free(slab, sk); 2198 else 2199 kfree(sk); 2200 return NULL; 2201 } 2202 2203 static void sk_prot_free(struct proto *prot, struct sock *sk) 2204 { 2205 struct kmem_cache *slab; 2206 struct module *owner; 2207 2208 owner = prot->owner; 2209 slab = prot->slab; 2210 2211 cgroup_sk_free(&sk->sk_cgrp_data); 2212 mem_cgroup_sk_free(sk); 2213 security_sk_free(sk); 2214 if (slab != NULL) 2215 kmem_cache_free(slab, sk); 2216 else 2217 kfree(sk); 2218 module_put(owner); 2219 } 2220 2221 /** 2222 * sk_alloc - All socket objects are allocated here 2223 * @net: the applicable net namespace 2224 * @family: protocol family 2225 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 2226 * @prot: struct proto associated with this new sock instance 2227 * @kern: is this to be a kernel socket? 2228 */ 2229 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 2230 struct proto *prot, int kern) 2231 { 2232 struct sock *sk; 2233 2234 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 2235 if (sk) { 2236 sk->sk_family = family; 2237 /* 2238 * See comment in struct sock definition to understand 2239 * why we need sk_prot_creator -acme 2240 */ 2241 sk->sk_prot = sk->sk_prot_creator = prot; 2242 sk->sk_kern_sock = kern; 2243 sock_lock_init(sk); 2244 sk->sk_net_refcnt = kern ? 0 : 1; 2245 if (likely(sk->sk_net_refcnt)) { 2246 get_net_track(net, &sk->ns_tracker, priority); 2247 sock_inuse_add(net, 1); 2248 } else { 2249 net_passive_inc(net); 2250 __netns_tracker_alloc(net, &sk->ns_tracker, 2251 false, priority); 2252 } 2253 2254 sock_net_set(sk, net); 2255 refcount_set(&sk->sk_wmem_alloc, 1); 2256 2257 mem_cgroup_sk_alloc(sk); 2258 cgroup_sk_alloc(&sk->sk_cgrp_data); 2259 sock_update_classid(&sk->sk_cgrp_data); 2260 sock_update_netprioidx(&sk->sk_cgrp_data); 2261 sk_tx_queue_clear(sk); 2262 } 2263 2264 return sk; 2265 } 2266 EXPORT_SYMBOL(sk_alloc); 2267 2268 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 2269 * grace period. This is the case for UDP sockets and TCP listeners. 2270 */ 2271 static void __sk_destruct(struct rcu_head *head) 2272 { 2273 struct sock *sk = container_of(head, struct sock, sk_rcu); 2274 struct net *net = sock_net(sk); 2275 struct sk_filter *filter; 2276 2277 if (sk->sk_destruct) 2278 sk->sk_destruct(sk); 2279 2280 filter = rcu_dereference_check(sk->sk_filter, 2281 refcount_read(&sk->sk_wmem_alloc) == 0); 2282 if (filter) { 2283 sk_filter_uncharge(sk, filter); 2284 RCU_INIT_POINTER(sk->sk_filter, NULL); 2285 } 2286 2287 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 2288 2289 #ifdef CONFIG_BPF_SYSCALL 2290 bpf_sk_storage_free(sk); 2291 #endif 2292 2293 if (atomic_read(&sk->sk_omem_alloc)) 2294 pr_debug("%s: optmem leakage (%d bytes) detected\n", 2295 __func__, atomic_read(&sk->sk_omem_alloc)); 2296 2297 if (sk->sk_frag.page) { 2298 put_page(sk->sk_frag.page); 2299 sk->sk_frag.page = NULL; 2300 } 2301 2302 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */ 2303 put_cred(sk->sk_peer_cred); 2304 put_pid(sk->sk_peer_pid); 2305 2306 if (likely(sk->sk_net_refcnt)) { 2307 put_net_track(net, &sk->ns_tracker); 2308 } else { 2309 __netns_tracker_free(net, &sk->ns_tracker, false); 2310 net_passive_dec(net); 2311 } 2312 sk_prot_free(sk->sk_prot_creator, sk); 2313 } 2314 2315 void sk_net_refcnt_upgrade(struct sock *sk) 2316 { 2317 struct net *net = sock_net(sk); 2318 2319 WARN_ON_ONCE(sk->sk_net_refcnt); 2320 __netns_tracker_free(net, &sk->ns_tracker, false); 2321 net_passive_dec(net); 2322 sk->sk_net_refcnt = 1; 2323 get_net_track(net, &sk->ns_tracker, GFP_KERNEL); 2324 sock_inuse_add(net, 1); 2325 } 2326 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade); 2327 2328 void sk_destruct(struct sock *sk) 2329 { 2330 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE); 2331 2332 if (rcu_access_pointer(sk->sk_reuseport_cb)) { 2333 reuseport_detach_sock(sk); 2334 use_call_rcu = true; 2335 } 2336 2337 if (use_call_rcu) 2338 call_rcu(&sk->sk_rcu, __sk_destruct); 2339 else 2340 __sk_destruct(&sk->sk_rcu); 2341 } 2342 2343 static void __sk_free(struct sock *sk) 2344 { 2345 if (likely(sk->sk_net_refcnt)) 2346 sock_inuse_add(sock_net(sk), -1); 2347 2348 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk))) 2349 sock_diag_broadcast_destroy(sk); 2350 else 2351 sk_destruct(sk); 2352 } 2353 2354 void sk_free(struct sock *sk) 2355 { 2356 /* 2357 * We subtract one from sk_wmem_alloc and can know if 2358 * some packets are still in some tx queue. 2359 * If not null, sock_wfree() will call __sk_free(sk) later 2360 */ 2361 if (refcount_dec_and_test(&sk->sk_wmem_alloc)) 2362 __sk_free(sk); 2363 } 2364 EXPORT_SYMBOL(sk_free); 2365 2366 static void sk_init_common(struct sock *sk) 2367 { 2368 skb_queue_head_init(&sk->sk_receive_queue); 2369 skb_queue_head_init(&sk->sk_write_queue); 2370 skb_queue_head_init(&sk->sk_error_queue); 2371 2372 rwlock_init(&sk->sk_callback_lock); 2373 lockdep_set_class_and_name(&sk->sk_receive_queue.lock, 2374 af_rlock_keys + sk->sk_family, 2375 af_family_rlock_key_strings[sk->sk_family]); 2376 lockdep_set_class_and_name(&sk->sk_write_queue.lock, 2377 af_wlock_keys + sk->sk_family, 2378 af_family_wlock_key_strings[sk->sk_family]); 2379 lockdep_set_class_and_name(&sk->sk_error_queue.lock, 2380 af_elock_keys + sk->sk_family, 2381 af_family_elock_key_strings[sk->sk_family]); 2382 if (sk->sk_kern_sock) 2383 lockdep_set_class_and_name(&sk->sk_callback_lock, 2384 af_kern_callback_keys + sk->sk_family, 2385 af_family_kern_clock_key_strings[sk->sk_family]); 2386 else 2387 lockdep_set_class_and_name(&sk->sk_callback_lock, 2388 af_callback_keys + sk->sk_family, 2389 af_family_clock_key_strings[sk->sk_family]); 2390 } 2391 2392 /** 2393 * sk_clone_lock - clone a socket, and lock its clone 2394 * @sk: the socket to clone 2395 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 2396 * 2397 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 2398 */ 2399 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 2400 { 2401 struct proto *prot = READ_ONCE(sk->sk_prot); 2402 struct sk_filter *filter; 2403 bool is_charged = true; 2404 struct sock *newsk; 2405 2406 newsk = sk_prot_alloc(prot, priority, sk->sk_family); 2407 if (!newsk) 2408 goto out; 2409 2410 sock_copy(newsk, sk); 2411 2412 newsk->sk_prot_creator = prot; 2413 2414 /* SANITY */ 2415 if (likely(newsk->sk_net_refcnt)) { 2416 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority); 2417 sock_inuse_add(sock_net(newsk), 1); 2418 } else { 2419 /* Kernel sockets are not elevating the struct net refcount. 2420 * Instead, use a tracker to more easily detect if a layer 2421 * is not properly dismantling its kernel sockets at netns 2422 * destroy time. 2423 */ 2424 net_passive_inc(sock_net(newsk)); 2425 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker, 2426 false, priority); 2427 } 2428 sk_node_init(&newsk->sk_node); 2429 sock_lock_init(newsk); 2430 bh_lock_sock(newsk); 2431 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 2432 newsk->sk_backlog.len = 0; 2433 2434 atomic_set(&newsk->sk_rmem_alloc, 0); 2435 2436 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */ 2437 refcount_set(&newsk->sk_wmem_alloc, 1); 2438 2439 atomic_set(&newsk->sk_omem_alloc, 0); 2440 sk_init_common(newsk); 2441 2442 newsk->sk_dst_cache = NULL; 2443 newsk->sk_dst_pending_confirm = 0; 2444 newsk->sk_wmem_queued = 0; 2445 newsk->sk_forward_alloc = 0; 2446 newsk->sk_reserved_mem = 0; 2447 atomic_set(&newsk->sk_drops, 0); 2448 newsk->sk_send_head = NULL; 2449 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 2450 atomic_set(&newsk->sk_zckey, 0); 2451 2452 sock_reset_flag(newsk, SOCK_DONE); 2453 2454 /* sk->sk_memcg will be populated at accept() time */ 2455 newsk->sk_memcg = NULL; 2456 2457 cgroup_sk_clone(&newsk->sk_cgrp_data); 2458 2459 rcu_read_lock(); 2460 filter = rcu_dereference(sk->sk_filter); 2461 if (filter != NULL) 2462 /* though it's an empty new sock, the charging may fail 2463 * if sysctl_optmem_max was changed between creation of 2464 * original socket and cloning 2465 */ 2466 is_charged = sk_filter_charge(newsk, filter); 2467 RCU_INIT_POINTER(newsk->sk_filter, filter); 2468 rcu_read_unlock(); 2469 2470 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 2471 /* We need to make sure that we don't uncharge the new 2472 * socket if we couldn't charge it in the first place 2473 * as otherwise we uncharge the parent's filter. 2474 */ 2475 if (!is_charged) 2476 RCU_INIT_POINTER(newsk->sk_filter, NULL); 2477 sk_free_unlock_clone(newsk); 2478 newsk = NULL; 2479 goto out; 2480 } 2481 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 2482 2483 if (bpf_sk_storage_clone(sk, newsk)) { 2484 sk_free_unlock_clone(newsk); 2485 newsk = NULL; 2486 goto out; 2487 } 2488 2489 /* Clear sk_user_data if parent had the pointer tagged 2490 * as not suitable for copying when cloning. 2491 */ 2492 if (sk_user_data_is_nocopy(newsk)) 2493 newsk->sk_user_data = NULL; 2494 2495 newsk->sk_err = 0; 2496 newsk->sk_err_soft = 0; 2497 newsk->sk_priority = 0; 2498 newsk->sk_incoming_cpu = raw_smp_processor_id(); 2499 2500 /* Before updating sk_refcnt, we must commit prior changes to memory 2501 * (Documentation/RCU/rculist_nulls.rst for details) 2502 */ 2503 smp_wmb(); 2504 refcount_set(&newsk->sk_refcnt, 2); 2505 2506 sk_set_socket(newsk, NULL); 2507 sk_tx_queue_clear(newsk); 2508 RCU_INIT_POINTER(newsk->sk_wq, NULL); 2509 2510 if (newsk->sk_prot->sockets_allocated) 2511 sk_sockets_allocated_inc(newsk); 2512 2513 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP) 2514 net_enable_timestamp(); 2515 out: 2516 return newsk; 2517 } 2518 EXPORT_SYMBOL_GPL(sk_clone_lock); 2519 2520 void sk_free_unlock_clone(struct sock *sk) 2521 { 2522 /* It is still raw copy of parent, so invalidate 2523 * destructor and make plain sk_free() */ 2524 sk->sk_destruct = NULL; 2525 bh_unlock_sock(sk); 2526 sk_free(sk); 2527 } 2528 EXPORT_SYMBOL_GPL(sk_free_unlock_clone); 2529 2530 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst) 2531 { 2532 bool is_ipv6 = false; 2533 u32 max_size; 2534 2535 #if IS_ENABLED(CONFIG_IPV6) 2536 is_ipv6 = (sk->sk_family == AF_INET6 && 2537 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)); 2538 #endif 2539 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */ 2540 max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) : 2541 READ_ONCE(dst->dev->gso_ipv4_max_size); 2542 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk)) 2543 max_size = GSO_LEGACY_MAX_SIZE; 2544 2545 return max_size - (MAX_TCP_HEADER + 1); 2546 } 2547 2548 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 2549 { 2550 u32 max_segs = 1; 2551 2552 sk->sk_route_caps = dst->dev->features; 2553 if (sk_is_tcp(sk)) 2554 sk->sk_route_caps |= NETIF_F_GSO; 2555 if (sk->sk_route_caps & NETIF_F_GSO) 2556 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 2557 if (unlikely(sk->sk_gso_disabled)) 2558 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2559 if (sk_can_gso(sk)) { 2560 if (dst->header_len && !xfrm_dst_offload_ok(dst)) { 2561 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2562 } else { 2563 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 2564 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst); 2565 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */ 2566 max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1); 2567 } 2568 } 2569 sk->sk_gso_max_segs = max_segs; 2570 sk_dst_set(sk, dst); 2571 } 2572 EXPORT_SYMBOL_GPL(sk_setup_caps); 2573 2574 /* 2575 * Simple resource managers for sockets. 2576 */ 2577 2578 2579 /* 2580 * Write buffer destructor automatically called from kfree_skb. 2581 */ 2582 void sock_wfree(struct sk_buff *skb) 2583 { 2584 struct sock *sk = skb->sk; 2585 unsigned int len = skb->truesize; 2586 bool free; 2587 2588 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 2589 if (sock_flag(sk, SOCK_RCU_FREE) && 2590 sk->sk_write_space == sock_def_write_space) { 2591 rcu_read_lock(); 2592 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc); 2593 sock_def_write_space_wfree(sk); 2594 rcu_read_unlock(); 2595 if (unlikely(free)) 2596 __sk_free(sk); 2597 return; 2598 } 2599 2600 /* 2601 * Keep a reference on sk_wmem_alloc, this will be released 2602 * after sk_write_space() call 2603 */ 2604 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); 2605 sk->sk_write_space(sk); 2606 len = 1; 2607 } 2608 /* 2609 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 2610 * could not do because of in-flight packets 2611 */ 2612 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc)) 2613 __sk_free(sk); 2614 } 2615 EXPORT_SYMBOL(sock_wfree); 2616 2617 /* This variant of sock_wfree() is used by TCP, 2618 * since it sets SOCK_USE_WRITE_QUEUE. 2619 */ 2620 void __sock_wfree(struct sk_buff *skb) 2621 { 2622 struct sock *sk = skb->sk; 2623 2624 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 2625 __sk_free(sk); 2626 } 2627 2628 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 2629 { 2630 skb_orphan(skb); 2631 #ifdef CONFIG_INET 2632 if (unlikely(!sk_fullsock(sk))) 2633 return skb_set_owner_edemux(skb, sk); 2634 #endif 2635 skb->sk = sk; 2636 skb->destructor = sock_wfree; 2637 skb_set_hash_from_sk(skb, sk); 2638 /* 2639 * We used to take a refcount on sk, but following operation 2640 * is enough to guarantee sk_free() won't free this sock until 2641 * all in-flight packets are completed 2642 */ 2643 refcount_add(skb->truesize, &sk->sk_wmem_alloc); 2644 } 2645 EXPORT_SYMBOL(skb_set_owner_w); 2646 2647 static bool can_skb_orphan_partial(const struct sk_buff *skb) 2648 { 2649 /* Drivers depend on in-order delivery for crypto offload, 2650 * partial orphan breaks out-of-order-OK logic. 2651 */ 2652 if (skb_is_decrypted(skb)) 2653 return false; 2654 2655 return (skb->destructor == sock_wfree || 2656 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree)); 2657 } 2658 2659 /* This helper is used by netem, as it can hold packets in its 2660 * delay queue. We want to allow the owner socket to send more 2661 * packets, as if they were already TX completed by a typical driver. 2662 * But we also want to keep skb->sk set because some packet schedulers 2663 * rely on it (sch_fq for example). 2664 */ 2665 void skb_orphan_partial(struct sk_buff *skb) 2666 { 2667 if (skb_is_tcp_pure_ack(skb)) 2668 return; 2669 2670 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk)) 2671 return; 2672 2673 skb_orphan(skb); 2674 } 2675 EXPORT_SYMBOL(skb_orphan_partial); 2676 2677 /* 2678 * Read buffer destructor automatically called from kfree_skb. 2679 */ 2680 void sock_rfree(struct sk_buff *skb) 2681 { 2682 struct sock *sk = skb->sk; 2683 unsigned int len = skb->truesize; 2684 2685 atomic_sub(len, &sk->sk_rmem_alloc); 2686 sk_mem_uncharge(sk, len); 2687 } 2688 EXPORT_SYMBOL(sock_rfree); 2689 2690 /* 2691 * Buffer destructor for skbs that are not used directly in read or write 2692 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 2693 */ 2694 void sock_efree(struct sk_buff *skb) 2695 { 2696 sock_put(skb->sk); 2697 } 2698 EXPORT_SYMBOL(sock_efree); 2699 2700 /* Buffer destructor for prefetch/receive path where reference count may 2701 * not be held, e.g. for listen sockets. 2702 */ 2703 #ifdef CONFIG_INET 2704 void sock_pfree(struct sk_buff *skb) 2705 { 2706 struct sock *sk = skb->sk; 2707 2708 if (!sk_is_refcounted(sk)) 2709 return; 2710 2711 if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) { 2712 inet_reqsk(sk)->rsk_listener = NULL; 2713 reqsk_free(inet_reqsk(sk)); 2714 return; 2715 } 2716 2717 sock_gen_put(sk); 2718 } 2719 EXPORT_SYMBOL(sock_pfree); 2720 #endif /* CONFIG_INET */ 2721 2722 kuid_t sock_i_uid(struct sock *sk) 2723 { 2724 kuid_t uid; 2725 2726 read_lock_bh(&sk->sk_callback_lock); 2727 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 2728 read_unlock_bh(&sk->sk_callback_lock); 2729 return uid; 2730 } 2731 EXPORT_SYMBOL(sock_i_uid); 2732 2733 unsigned long __sock_i_ino(struct sock *sk) 2734 { 2735 unsigned long ino; 2736 2737 read_lock(&sk->sk_callback_lock); 2738 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 2739 read_unlock(&sk->sk_callback_lock); 2740 return ino; 2741 } 2742 EXPORT_SYMBOL(__sock_i_ino); 2743 2744 unsigned long sock_i_ino(struct sock *sk) 2745 { 2746 unsigned long ino; 2747 2748 local_bh_disable(); 2749 ino = __sock_i_ino(sk); 2750 local_bh_enable(); 2751 return ino; 2752 } 2753 EXPORT_SYMBOL(sock_i_ino); 2754 2755 /* 2756 * Allocate a skb from the socket's send buffer. 2757 */ 2758 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 2759 gfp_t priority) 2760 { 2761 if (force || 2762 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) { 2763 struct sk_buff *skb = alloc_skb(size, priority); 2764 2765 if (skb) { 2766 skb_set_owner_w(skb, sk); 2767 return skb; 2768 } 2769 } 2770 return NULL; 2771 } 2772 EXPORT_SYMBOL(sock_wmalloc); 2773 2774 static void sock_ofree(struct sk_buff *skb) 2775 { 2776 struct sock *sk = skb->sk; 2777 2778 atomic_sub(skb->truesize, &sk->sk_omem_alloc); 2779 } 2780 2781 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 2782 gfp_t priority) 2783 { 2784 struct sk_buff *skb; 2785 2786 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */ 2787 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) > 2788 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max)) 2789 return NULL; 2790 2791 skb = alloc_skb(size, priority); 2792 if (!skb) 2793 return NULL; 2794 2795 atomic_add(skb->truesize, &sk->sk_omem_alloc); 2796 skb->sk = sk; 2797 skb->destructor = sock_ofree; 2798 return skb; 2799 } 2800 2801 /* 2802 * Allocate a memory block from the socket's option memory buffer. 2803 */ 2804 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 2805 { 2806 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max); 2807 2808 if ((unsigned int)size <= optmem_max && 2809 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) { 2810 void *mem; 2811 /* First do the add, to avoid the race if kmalloc 2812 * might sleep. 2813 */ 2814 atomic_add(size, &sk->sk_omem_alloc); 2815 mem = kmalloc(size, priority); 2816 if (mem) 2817 return mem; 2818 atomic_sub(size, &sk->sk_omem_alloc); 2819 } 2820 return NULL; 2821 } 2822 EXPORT_SYMBOL(sock_kmalloc); 2823 2824 /* Free an option memory block. Note, we actually want the inline 2825 * here as this allows gcc to detect the nullify and fold away the 2826 * condition entirely. 2827 */ 2828 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 2829 const bool nullify) 2830 { 2831 if (WARN_ON_ONCE(!mem)) 2832 return; 2833 if (nullify) 2834 kfree_sensitive(mem); 2835 else 2836 kfree(mem); 2837 atomic_sub(size, &sk->sk_omem_alloc); 2838 } 2839 2840 void sock_kfree_s(struct sock *sk, void *mem, int size) 2841 { 2842 __sock_kfree_s(sk, mem, size, false); 2843 } 2844 EXPORT_SYMBOL(sock_kfree_s); 2845 2846 void sock_kzfree_s(struct sock *sk, void *mem, int size) 2847 { 2848 __sock_kfree_s(sk, mem, size, true); 2849 } 2850 EXPORT_SYMBOL(sock_kzfree_s); 2851 2852 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 2853 I think, these locks should be removed for datagram sockets. 2854 */ 2855 static long sock_wait_for_wmem(struct sock *sk, long timeo) 2856 { 2857 DEFINE_WAIT(wait); 2858 2859 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2860 for (;;) { 2861 if (!timeo) 2862 break; 2863 if (signal_pending(current)) 2864 break; 2865 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2866 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 2867 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) 2868 break; 2869 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN) 2870 break; 2871 if (READ_ONCE(sk->sk_err)) 2872 break; 2873 timeo = schedule_timeout(timeo); 2874 } 2875 finish_wait(sk_sleep(sk), &wait); 2876 return timeo; 2877 } 2878 2879 2880 /* 2881 * Generic send/receive buffer handlers 2882 */ 2883 2884 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 2885 unsigned long data_len, int noblock, 2886 int *errcode, int max_page_order) 2887 { 2888 struct sk_buff *skb; 2889 long timeo; 2890 int err; 2891 2892 timeo = sock_sndtimeo(sk, noblock); 2893 for (;;) { 2894 err = sock_error(sk); 2895 if (err != 0) 2896 goto failure; 2897 2898 err = -EPIPE; 2899 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN) 2900 goto failure; 2901 2902 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf)) 2903 break; 2904 2905 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2906 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2907 err = -EAGAIN; 2908 if (!timeo) 2909 goto failure; 2910 if (signal_pending(current)) 2911 goto interrupted; 2912 timeo = sock_wait_for_wmem(sk, timeo); 2913 } 2914 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 2915 errcode, sk->sk_allocation); 2916 if (skb) 2917 skb_set_owner_w(skb, sk); 2918 return skb; 2919 2920 interrupted: 2921 err = sock_intr_errno(timeo); 2922 failure: 2923 *errcode = err; 2924 return NULL; 2925 } 2926 EXPORT_SYMBOL(sock_alloc_send_pskb); 2927 2928 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 2929 struct sockcm_cookie *sockc) 2930 { 2931 u32 tsflags; 2932 2933 BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31)); 2934 2935 switch (cmsg->cmsg_type) { 2936 case SO_MARK: 2937 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && 2938 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 2939 return -EPERM; 2940 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2941 return -EINVAL; 2942 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 2943 break; 2944 case SO_TIMESTAMPING_OLD: 2945 case SO_TIMESTAMPING_NEW: 2946 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2947 return -EINVAL; 2948 2949 tsflags = *(u32 *)CMSG_DATA(cmsg); 2950 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 2951 return -EINVAL; 2952 2953 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 2954 sockc->tsflags |= tsflags; 2955 break; 2956 case SCM_TXTIME: 2957 if (!sock_flag(sk, SOCK_TXTIME)) 2958 return -EINVAL; 2959 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64))) 2960 return -EINVAL; 2961 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg)); 2962 break; 2963 case SCM_TS_OPT_ID: 2964 if (sk_is_tcp(sk)) 2965 return -EINVAL; 2966 tsflags = READ_ONCE(sk->sk_tsflags); 2967 if (!(tsflags & SOF_TIMESTAMPING_OPT_ID)) 2968 return -EINVAL; 2969 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2970 return -EINVAL; 2971 sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg); 2972 sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID; 2973 break; 2974 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 2975 case SCM_RIGHTS: 2976 case SCM_CREDENTIALS: 2977 break; 2978 case SO_PRIORITY: 2979 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2980 return -EINVAL; 2981 if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg))) 2982 return -EPERM; 2983 sockc->priority = *(u32 *)CMSG_DATA(cmsg); 2984 break; 2985 default: 2986 return -EINVAL; 2987 } 2988 return 0; 2989 } 2990 EXPORT_SYMBOL(__sock_cmsg_send); 2991 2992 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 2993 struct sockcm_cookie *sockc) 2994 { 2995 struct cmsghdr *cmsg; 2996 int ret; 2997 2998 for_each_cmsghdr(cmsg, msg) { 2999 if (!CMSG_OK(msg, cmsg)) 3000 return -EINVAL; 3001 if (cmsg->cmsg_level != SOL_SOCKET) 3002 continue; 3003 ret = __sock_cmsg_send(sk, cmsg, sockc); 3004 if (ret) 3005 return ret; 3006 } 3007 return 0; 3008 } 3009 EXPORT_SYMBOL(sock_cmsg_send); 3010 3011 static void sk_enter_memory_pressure(struct sock *sk) 3012 { 3013 if (!sk->sk_prot->enter_memory_pressure) 3014 return; 3015 3016 sk->sk_prot->enter_memory_pressure(sk); 3017 } 3018 3019 static void sk_leave_memory_pressure(struct sock *sk) 3020 { 3021 if (sk->sk_prot->leave_memory_pressure) { 3022 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure, 3023 tcp_leave_memory_pressure, sk); 3024 } else { 3025 unsigned long *memory_pressure = sk->sk_prot->memory_pressure; 3026 3027 if (memory_pressure && READ_ONCE(*memory_pressure)) 3028 WRITE_ONCE(*memory_pressure, 0); 3029 } 3030 } 3031 3032 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 3033 3034 /** 3035 * skb_page_frag_refill - check that a page_frag contains enough room 3036 * @sz: minimum size of the fragment we want to get 3037 * @pfrag: pointer to page_frag 3038 * @gfp: priority for memory allocation 3039 * 3040 * Note: While this allocator tries to use high order pages, there is 3041 * no guarantee that allocations succeed. Therefore, @sz MUST be 3042 * less or equal than PAGE_SIZE. 3043 */ 3044 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 3045 { 3046 if (pfrag->page) { 3047 if (page_ref_count(pfrag->page) == 1) { 3048 pfrag->offset = 0; 3049 return true; 3050 } 3051 if (pfrag->offset + sz <= pfrag->size) 3052 return true; 3053 put_page(pfrag->page); 3054 } 3055 3056 pfrag->offset = 0; 3057 if (SKB_FRAG_PAGE_ORDER && 3058 !static_branch_unlikely(&net_high_order_alloc_disable_key)) { 3059 /* Avoid direct reclaim but allow kswapd to wake */ 3060 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 3061 __GFP_COMP | __GFP_NOWARN | 3062 __GFP_NORETRY, 3063 SKB_FRAG_PAGE_ORDER); 3064 if (likely(pfrag->page)) { 3065 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 3066 return true; 3067 } 3068 } 3069 pfrag->page = alloc_page(gfp); 3070 if (likely(pfrag->page)) { 3071 pfrag->size = PAGE_SIZE; 3072 return true; 3073 } 3074 return false; 3075 } 3076 EXPORT_SYMBOL(skb_page_frag_refill); 3077 3078 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 3079 { 3080 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 3081 return true; 3082 3083 sk_enter_memory_pressure(sk); 3084 sk_stream_moderate_sndbuf(sk); 3085 return false; 3086 } 3087 EXPORT_SYMBOL(sk_page_frag_refill); 3088 3089 void __lock_sock(struct sock *sk) 3090 __releases(&sk->sk_lock.slock) 3091 __acquires(&sk->sk_lock.slock) 3092 { 3093 DEFINE_WAIT(wait); 3094 3095 for (;;) { 3096 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 3097 TASK_UNINTERRUPTIBLE); 3098 spin_unlock_bh(&sk->sk_lock.slock); 3099 schedule(); 3100 spin_lock_bh(&sk->sk_lock.slock); 3101 if (!sock_owned_by_user(sk)) 3102 break; 3103 } 3104 finish_wait(&sk->sk_lock.wq, &wait); 3105 } 3106 3107 void __release_sock(struct sock *sk) 3108 __releases(&sk->sk_lock.slock) 3109 __acquires(&sk->sk_lock.slock) 3110 { 3111 struct sk_buff *skb, *next; 3112 3113 while ((skb = sk->sk_backlog.head) != NULL) { 3114 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 3115 3116 spin_unlock_bh(&sk->sk_lock.slock); 3117 3118 do { 3119 next = skb->next; 3120 prefetch(next); 3121 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb)); 3122 skb_mark_not_on_list(skb); 3123 sk_backlog_rcv(sk, skb); 3124 3125 cond_resched(); 3126 3127 skb = next; 3128 } while (skb != NULL); 3129 3130 spin_lock_bh(&sk->sk_lock.slock); 3131 } 3132 3133 /* 3134 * Doing the zeroing here guarantee we can not loop forever 3135 * while a wild producer attempts to flood us. 3136 */ 3137 sk->sk_backlog.len = 0; 3138 } 3139 3140 void __sk_flush_backlog(struct sock *sk) 3141 { 3142 spin_lock_bh(&sk->sk_lock.slock); 3143 __release_sock(sk); 3144 3145 if (sk->sk_prot->release_cb) 3146 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb, 3147 tcp_release_cb, sk); 3148 3149 spin_unlock_bh(&sk->sk_lock.slock); 3150 } 3151 EXPORT_SYMBOL_GPL(__sk_flush_backlog); 3152 3153 /** 3154 * sk_wait_data - wait for data to arrive at sk_receive_queue 3155 * @sk: sock to wait on 3156 * @timeo: for how long 3157 * @skb: last skb seen on sk_receive_queue 3158 * 3159 * Now socket state including sk->sk_err is changed only under lock, 3160 * hence we may omit checks after joining wait queue. 3161 * We check receive queue before schedule() only as optimization; 3162 * it is very likely that release_sock() added new data. 3163 */ 3164 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 3165 { 3166 DEFINE_WAIT_FUNC(wait, woken_wake_function); 3167 int rc; 3168 3169 add_wait_queue(sk_sleep(sk), &wait); 3170 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 3171 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); 3172 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 3173 remove_wait_queue(sk_sleep(sk), &wait); 3174 return rc; 3175 } 3176 EXPORT_SYMBOL(sk_wait_data); 3177 3178 /** 3179 * __sk_mem_raise_allocated - increase memory_allocated 3180 * @sk: socket 3181 * @size: memory size to allocate 3182 * @amt: pages to allocate 3183 * @kind: allocation type 3184 * 3185 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc. 3186 * 3187 * Unlike the globally shared limits among the sockets under same protocol, 3188 * consuming the budget of a memcg won't have direct effect on other ones. 3189 * So be optimistic about memcg's tolerance, and leave the callers to decide 3190 * whether or not to raise allocated through sk_under_memory_pressure() or 3191 * its variants. 3192 */ 3193 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) 3194 { 3195 struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL; 3196 struct proto *prot = sk->sk_prot; 3197 bool charged = false; 3198 long allocated; 3199 3200 sk_memory_allocated_add(sk, amt); 3201 allocated = sk_memory_allocated(sk); 3202 3203 if (memcg) { 3204 if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge())) 3205 goto suppress_allocation; 3206 charged = true; 3207 } 3208 3209 /* Under limit. */ 3210 if (allocated <= sk_prot_mem_limits(sk, 0)) { 3211 sk_leave_memory_pressure(sk); 3212 return 1; 3213 } 3214 3215 /* Under pressure. */ 3216 if (allocated > sk_prot_mem_limits(sk, 1)) 3217 sk_enter_memory_pressure(sk); 3218 3219 /* Over hard limit. */ 3220 if (allocated > sk_prot_mem_limits(sk, 2)) 3221 goto suppress_allocation; 3222 3223 /* Guarantee minimum buffer size under pressure (either global 3224 * or memcg) to make sure features described in RFC 7323 (TCP 3225 * Extensions for High Performance) work properly. 3226 * 3227 * This rule does NOT stand when exceeds global or memcg's hard 3228 * limit, or else a DoS attack can be taken place by spawning 3229 * lots of sockets whose usage are under minimum buffer size. 3230 */ 3231 if (kind == SK_MEM_RECV) { 3232 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot)) 3233 return 1; 3234 3235 } else { /* SK_MEM_SEND */ 3236 int wmem0 = sk_get_wmem0(sk, prot); 3237 3238 if (sk->sk_type == SOCK_STREAM) { 3239 if (sk->sk_wmem_queued < wmem0) 3240 return 1; 3241 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) { 3242 return 1; 3243 } 3244 } 3245 3246 if (sk_has_memory_pressure(sk)) { 3247 u64 alloc; 3248 3249 /* The following 'average' heuristic is within the 3250 * scope of global accounting, so it only makes 3251 * sense for global memory pressure. 3252 */ 3253 if (!sk_under_global_memory_pressure(sk)) 3254 return 1; 3255 3256 /* Try to be fair among all the sockets under global 3257 * pressure by allowing the ones that below average 3258 * usage to raise. 3259 */ 3260 alloc = sk_sockets_allocated_read_positive(sk); 3261 if (sk_prot_mem_limits(sk, 2) > alloc * 3262 sk_mem_pages(sk->sk_wmem_queued + 3263 atomic_read(&sk->sk_rmem_alloc) + 3264 sk->sk_forward_alloc)) 3265 return 1; 3266 } 3267 3268 suppress_allocation: 3269 3270 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 3271 sk_stream_moderate_sndbuf(sk); 3272 3273 /* Fail only if socket is _under_ its sndbuf. 3274 * In this case we cannot block, so that we have to fail. 3275 */ 3276 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) { 3277 /* Force charge with __GFP_NOFAIL */ 3278 if (memcg && !charged) { 3279 mem_cgroup_charge_skmem(memcg, amt, 3280 gfp_memcg_charge() | __GFP_NOFAIL); 3281 } 3282 return 1; 3283 } 3284 } 3285 3286 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) 3287 trace_sock_exceed_buf_limit(sk, prot, allocated, kind); 3288 3289 sk_memory_allocated_sub(sk, amt); 3290 3291 if (charged) 3292 mem_cgroup_uncharge_skmem(memcg, amt); 3293 3294 return 0; 3295 } 3296 3297 /** 3298 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 3299 * @sk: socket 3300 * @size: memory size to allocate 3301 * @kind: allocation type 3302 * 3303 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 3304 * rmem allocation. This function assumes that protocols which have 3305 * memory_pressure use sk_wmem_queued as write buffer accounting. 3306 */ 3307 int __sk_mem_schedule(struct sock *sk, int size, int kind) 3308 { 3309 int ret, amt = sk_mem_pages(size); 3310 3311 sk_forward_alloc_add(sk, amt << PAGE_SHIFT); 3312 ret = __sk_mem_raise_allocated(sk, size, amt, kind); 3313 if (!ret) 3314 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT)); 3315 return ret; 3316 } 3317 EXPORT_SYMBOL(__sk_mem_schedule); 3318 3319 /** 3320 * __sk_mem_reduce_allocated - reclaim memory_allocated 3321 * @sk: socket 3322 * @amount: number of quanta 3323 * 3324 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc 3325 */ 3326 void __sk_mem_reduce_allocated(struct sock *sk, int amount) 3327 { 3328 sk_memory_allocated_sub(sk, amount); 3329 3330 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 3331 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 3332 3333 if (sk_under_global_memory_pressure(sk) && 3334 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 3335 sk_leave_memory_pressure(sk); 3336 } 3337 3338 /** 3339 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated 3340 * @sk: socket 3341 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple) 3342 */ 3343 void __sk_mem_reclaim(struct sock *sk, int amount) 3344 { 3345 amount >>= PAGE_SHIFT; 3346 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT)); 3347 __sk_mem_reduce_allocated(sk, amount); 3348 } 3349 EXPORT_SYMBOL(__sk_mem_reclaim); 3350 3351 int sk_set_peek_off(struct sock *sk, int val) 3352 { 3353 WRITE_ONCE(sk->sk_peek_off, val); 3354 return 0; 3355 } 3356 EXPORT_SYMBOL_GPL(sk_set_peek_off); 3357 3358 /* 3359 * Set of default routines for initialising struct proto_ops when 3360 * the protocol does not support a particular function. In certain 3361 * cases where it makes no sense for a protocol to have a "do nothing" 3362 * function, some default processing is provided. 3363 */ 3364 3365 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 3366 { 3367 return -EOPNOTSUPP; 3368 } 3369 EXPORT_SYMBOL(sock_no_bind); 3370 3371 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 3372 int len, int flags) 3373 { 3374 return -EOPNOTSUPP; 3375 } 3376 EXPORT_SYMBOL(sock_no_connect); 3377 3378 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 3379 { 3380 return -EOPNOTSUPP; 3381 } 3382 EXPORT_SYMBOL(sock_no_socketpair); 3383 3384 int sock_no_accept(struct socket *sock, struct socket *newsock, 3385 struct proto_accept_arg *arg) 3386 { 3387 return -EOPNOTSUPP; 3388 } 3389 EXPORT_SYMBOL(sock_no_accept); 3390 3391 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 3392 int peer) 3393 { 3394 return -EOPNOTSUPP; 3395 } 3396 EXPORT_SYMBOL(sock_no_getname); 3397 3398 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 3399 { 3400 return -EOPNOTSUPP; 3401 } 3402 EXPORT_SYMBOL(sock_no_ioctl); 3403 3404 int sock_no_listen(struct socket *sock, int backlog) 3405 { 3406 return -EOPNOTSUPP; 3407 } 3408 EXPORT_SYMBOL(sock_no_listen); 3409 3410 int sock_no_shutdown(struct socket *sock, int how) 3411 { 3412 return -EOPNOTSUPP; 3413 } 3414 EXPORT_SYMBOL(sock_no_shutdown); 3415 3416 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 3417 { 3418 return -EOPNOTSUPP; 3419 } 3420 EXPORT_SYMBOL(sock_no_sendmsg); 3421 3422 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len) 3423 { 3424 return -EOPNOTSUPP; 3425 } 3426 EXPORT_SYMBOL(sock_no_sendmsg_locked); 3427 3428 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 3429 int flags) 3430 { 3431 return -EOPNOTSUPP; 3432 } 3433 EXPORT_SYMBOL(sock_no_recvmsg); 3434 3435 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 3436 { 3437 /* Mirror missing mmap method error code */ 3438 return -ENODEV; 3439 } 3440 EXPORT_SYMBOL(sock_no_mmap); 3441 3442 /* 3443 * When a file is received (via SCM_RIGHTS, etc), we must bump the 3444 * various sock-based usage counts. 3445 */ 3446 void __receive_sock(struct file *file) 3447 { 3448 struct socket *sock; 3449 3450 sock = sock_from_file(file); 3451 if (sock) { 3452 sock_update_netprioidx(&sock->sk->sk_cgrp_data); 3453 sock_update_classid(&sock->sk->sk_cgrp_data); 3454 } 3455 } 3456 3457 /* 3458 * Default Socket Callbacks 3459 */ 3460 3461 static void sock_def_wakeup(struct sock *sk) 3462 { 3463 struct socket_wq *wq; 3464 3465 rcu_read_lock(); 3466 wq = rcu_dereference(sk->sk_wq); 3467 if (skwq_has_sleeper(wq)) 3468 wake_up_interruptible_all(&wq->wait); 3469 rcu_read_unlock(); 3470 } 3471 3472 static void sock_def_error_report(struct sock *sk) 3473 { 3474 struct socket_wq *wq; 3475 3476 rcu_read_lock(); 3477 wq = rcu_dereference(sk->sk_wq); 3478 if (skwq_has_sleeper(wq)) 3479 wake_up_interruptible_poll(&wq->wait, EPOLLERR); 3480 sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR); 3481 rcu_read_unlock(); 3482 } 3483 3484 void sock_def_readable(struct sock *sk) 3485 { 3486 struct socket_wq *wq; 3487 3488 trace_sk_data_ready(sk); 3489 3490 rcu_read_lock(); 3491 wq = rcu_dereference(sk->sk_wq); 3492 if (skwq_has_sleeper(wq)) 3493 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI | 3494 EPOLLRDNORM | EPOLLRDBAND); 3495 sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN); 3496 rcu_read_unlock(); 3497 } 3498 3499 static void sock_def_write_space(struct sock *sk) 3500 { 3501 struct socket_wq *wq; 3502 3503 rcu_read_lock(); 3504 3505 /* Do not wake up a writer until he can make "significant" 3506 * progress. --DaveM 3507 */ 3508 if (sock_writeable(sk)) { 3509 wq = rcu_dereference(sk->sk_wq); 3510 if (skwq_has_sleeper(wq)) 3511 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 3512 EPOLLWRNORM | EPOLLWRBAND); 3513 3514 /* Should agree with poll, otherwise some programs break */ 3515 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT); 3516 } 3517 3518 rcu_read_unlock(); 3519 } 3520 3521 /* An optimised version of sock_def_write_space(), should only be called 3522 * for SOCK_RCU_FREE sockets under RCU read section and after putting 3523 * ->sk_wmem_alloc. 3524 */ 3525 static void sock_def_write_space_wfree(struct sock *sk) 3526 { 3527 /* Do not wake up a writer until he can make "significant" 3528 * progress. --DaveM 3529 */ 3530 if (sock_writeable(sk)) { 3531 struct socket_wq *wq = rcu_dereference(sk->sk_wq); 3532 3533 /* rely on refcount_sub from sock_wfree() */ 3534 smp_mb__after_atomic(); 3535 if (wq && waitqueue_active(&wq->wait)) 3536 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 3537 EPOLLWRNORM | EPOLLWRBAND); 3538 3539 /* Should agree with poll, otherwise some programs break */ 3540 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT); 3541 } 3542 } 3543 3544 static void sock_def_destruct(struct sock *sk) 3545 { 3546 } 3547 3548 void sk_send_sigurg(struct sock *sk) 3549 { 3550 if (sk->sk_socket && sk->sk_socket->file) 3551 if (send_sigurg(sk->sk_socket->file)) 3552 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 3553 } 3554 EXPORT_SYMBOL(sk_send_sigurg); 3555 3556 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 3557 unsigned long expires) 3558 { 3559 if (!mod_timer(timer, expires)) 3560 sock_hold(sk); 3561 } 3562 EXPORT_SYMBOL(sk_reset_timer); 3563 3564 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 3565 { 3566 if (del_timer(timer)) 3567 __sock_put(sk); 3568 } 3569 EXPORT_SYMBOL(sk_stop_timer); 3570 3571 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer) 3572 { 3573 if (del_timer_sync(timer)) 3574 __sock_put(sk); 3575 } 3576 EXPORT_SYMBOL(sk_stop_timer_sync); 3577 3578 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid) 3579 { 3580 sk_init_common(sk); 3581 sk->sk_send_head = NULL; 3582 3583 timer_setup(&sk->sk_timer, NULL, 0); 3584 3585 sk->sk_allocation = GFP_KERNEL; 3586 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default); 3587 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default); 3588 sk->sk_state = TCP_CLOSE; 3589 sk->sk_use_task_frag = true; 3590 sk_set_socket(sk, sock); 3591 3592 sock_set_flag(sk, SOCK_ZAPPED); 3593 3594 if (sock) { 3595 sk->sk_type = sock->type; 3596 RCU_INIT_POINTER(sk->sk_wq, &sock->wq); 3597 sock->sk = sk; 3598 } else { 3599 RCU_INIT_POINTER(sk->sk_wq, NULL); 3600 } 3601 sk->sk_uid = uid; 3602 3603 sk->sk_state_change = sock_def_wakeup; 3604 sk->sk_data_ready = sock_def_readable; 3605 sk->sk_write_space = sock_def_write_space; 3606 sk->sk_error_report = sock_def_error_report; 3607 sk->sk_destruct = sock_def_destruct; 3608 3609 sk->sk_frag.page = NULL; 3610 sk->sk_frag.offset = 0; 3611 sk->sk_peek_off = -1; 3612 3613 sk->sk_peer_pid = NULL; 3614 sk->sk_peer_cred = NULL; 3615 spin_lock_init(&sk->sk_peer_lock); 3616 3617 sk->sk_write_pending = 0; 3618 sk->sk_rcvlowat = 1; 3619 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 3620 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 3621 3622 sk->sk_stamp = SK_DEFAULT_STAMP; 3623 #if BITS_PER_LONG==32 3624 seqlock_init(&sk->sk_stamp_seq); 3625 #endif 3626 atomic_set(&sk->sk_zckey, 0); 3627 3628 #ifdef CONFIG_NET_RX_BUSY_POLL 3629 sk->sk_napi_id = 0; 3630 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read); 3631 #endif 3632 3633 sk->sk_max_pacing_rate = ~0UL; 3634 sk->sk_pacing_rate = ~0UL; 3635 WRITE_ONCE(sk->sk_pacing_shift, 10); 3636 sk->sk_incoming_cpu = -1; 3637 3638 sk_rx_queue_clear(sk); 3639 /* 3640 * Before updating sk_refcnt, we must commit prior changes to memory 3641 * (Documentation/RCU/rculist_nulls.rst for details) 3642 */ 3643 smp_wmb(); 3644 refcount_set(&sk->sk_refcnt, 1); 3645 atomic_set(&sk->sk_drops, 0); 3646 } 3647 EXPORT_SYMBOL(sock_init_data_uid); 3648 3649 void sock_init_data(struct socket *sock, struct sock *sk) 3650 { 3651 kuid_t uid = sock ? 3652 SOCK_INODE(sock)->i_uid : 3653 make_kuid(sock_net(sk)->user_ns, 0); 3654 3655 sock_init_data_uid(sock, sk, uid); 3656 } 3657 EXPORT_SYMBOL(sock_init_data); 3658 3659 void lock_sock_nested(struct sock *sk, int subclass) 3660 { 3661 /* The sk_lock has mutex_lock() semantics here. */ 3662 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 3663 3664 might_sleep(); 3665 spin_lock_bh(&sk->sk_lock.slock); 3666 if (sock_owned_by_user_nocheck(sk)) 3667 __lock_sock(sk); 3668 sk->sk_lock.owned = 1; 3669 spin_unlock_bh(&sk->sk_lock.slock); 3670 } 3671 EXPORT_SYMBOL(lock_sock_nested); 3672 3673 void release_sock(struct sock *sk) 3674 { 3675 spin_lock_bh(&sk->sk_lock.slock); 3676 if (sk->sk_backlog.tail) 3677 __release_sock(sk); 3678 3679 if (sk->sk_prot->release_cb) 3680 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb, 3681 tcp_release_cb, sk); 3682 3683 sock_release_ownership(sk); 3684 if (waitqueue_active(&sk->sk_lock.wq)) 3685 wake_up(&sk->sk_lock.wq); 3686 spin_unlock_bh(&sk->sk_lock.slock); 3687 } 3688 EXPORT_SYMBOL(release_sock); 3689 3690 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock) 3691 { 3692 might_sleep(); 3693 spin_lock_bh(&sk->sk_lock.slock); 3694 3695 if (!sock_owned_by_user_nocheck(sk)) { 3696 /* 3697 * Fast path return with bottom halves disabled and 3698 * sock::sk_lock.slock held. 3699 * 3700 * The 'mutex' is not contended and holding 3701 * sock::sk_lock.slock prevents all other lockers to 3702 * proceed so the corresponding unlock_sock_fast() can 3703 * avoid the slow path of release_sock() completely and 3704 * just release slock. 3705 * 3706 * From a semantical POV this is equivalent to 'acquiring' 3707 * the 'mutex', hence the corresponding lockdep 3708 * mutex_release() has to happen in the fast path of 3709 * unlock_sock_fast(). 3710 */ 3711 return false; 3712 } 3713 3714 __lock_sock(sk); 3715 sk->sk_lock.owned = 1; 3716 __acquire(&sk->sk_lock.slock); 3717 spin_unlock_bh(&sk->sk_lock.slock); 3718 return true; 3719 } 3720 EXPORT_SYMBOL(__lock_sock_fast); 3721 3722 int sock_gettstamp(struct socket *sock, void __user *userstamp, 3723 bool timeval, bool time32) 3724 { 3725 struct sock *sk = sock->sk; 3726 struct timespec64 ts; 3727 3728 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 3729 ts = ktime_to_timespec64(sock_read_timestamp(sk)); 3730 if (ts.tv_sec == -1) 3731 return -ENOENT; 3732 if (ts.tv_sec == 0) { 3733 ktime_t kt = ktime_get_real(); 3734 sock_write_timestamp(sk, kt); 3735 ts = ktime_to_timespec64(kt); 3736 } 3737 3738 if (timeval) 3739 ts.tv_nsec /= 1000; 3740 3741 #ifdef CONFIG_COMPAT_32BIT_TIME 3742 if (time32) 3743 return put_old_timespec32(&ts, userstamp); 3744 #endif 3745 #ifdef CONFIG_SPARC64 3746 /* beware of padding in sparc64 timeval */ 3747 if (timeval && !in_compat_syscall()) { 3748 struct __kernel_old_timeval __user tv = { 3749 .tv_sec = ts.tv_sec, 3750 .tv_usec = ts.tv_nsec, 3751 }; 3752 if (copy_to_user(userstamp, &tv, sizeof(tv))) 3753 return -EFAULT; 3754 return 0; 3755 } 3756 #endif 3757 return put_timespec64(&ts, userstamp); 3758 } 3759 EXPORT_SYMBOL(sock_gettstamp); 3760 3761 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag) 3762 { 3763 if (!sock_flag(sk, flag)) { 3764 unsigned long previous_flags = sk->sk_flags; 3765 3766 sock_set_flag(sk, flag); 3767 /* 3768 * we just set one of the two flags which require net 3769 * time stamping, but time stamping might have been on 3770 * already because of the other one 3771 */ 3772 if (sock_needs_netstamp(sk) && 3773 !(previous_flags & SK_FLAGS_TIMESTAMP)) 3774 net_enable_timestamp(); 3775 } 3776 } 3777 3778 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 3779 int level, int type) 3780 { 3781 struct sock_exterr_skb *serr; 3782 struct sk_buff *skb; 3783 int copied, err; 3784 3785 err = -EAGAIN; 3786 skb = sock_dequeue_err_skb(sk); 3787 if (skb == NULL) 3788 goto out; 3789 3790 copied = skb->len; 3791 if (copied > len) { 3792 msg->msg_flags |= MSG_TRUNC; 3793 copied = len; 3794 } 3795 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3796 if (err) 3797 goto out_free_skb; 3798 3799 sock_recv_timestamp(msg, sk, skb); 3800 3801 serr = SKB_EXT_ERR(skb); 3802 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 3803 3804 msg->msg_flags |= MSG_ERRQUEUE; 3805 err = copied; 3806 3807 out_free_skb: 3808 kfree_skb(skb); 3809 out: 3810 return err; 3811 } 3812 EXPORT_SYMBOL(sock_recv_errqueue); 3813 3814 /* 3815 * Get a socket option on an socket. 3816 * 3817 * FIX: POSIX 1003.1g is very ambiguous here. It states that 3818 * asynchronous errors should be reported by getsockopt. We assume 3819 * this means if you specify SO_ERROR (otherwise what is the point of it). 3820 */ 3821 int sock_common_getsockopt(struct socket *sock, int level, int optname, 3822 char __user *optval, int __user *optlen) 3823 { 3824 struct sock *sk = sock->sk; 3825 3826 /* IPV6_ADDRFORM can change sk->sk_prot under us. */ 3827 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen); 3828 } 3829 EXPORT_SYMBOL(sock_common_getsockopt); 3830 3831 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 3832 int flags) 3833 { 3834 struct sock *sk = sock->sk; 3835 int addr_len = 0; 3836 int err; 3837 3838 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len); 3839 if (err >= 0) 3840 msg->msg_namelen = addr_len; 3841 return err; 3842 } 3843 EXPORT_SYMBOL(sock_common_recvmsg); 3844 3845 /* 3846 * Set socket options on an inet socket. 3847 */ 3848 int sock_common_setsockopt(struct socket *sock, int level, int optname, 3849 sockptr_t optval, unsigned int optlen) 3850 { 3851 struct sock *sk = sock->sk; 3852 3853 /* IPV6_ADDRFORM can change sk->sk_prot under us. */ 3854 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen); 3855 } 3856 EXPORT_SYMBOL(sock_common_setsockopt); 3857 3858 void sk_common_release(struct sock *sk) 3859 { 3860 if (sk->sk_prot->destroy) 3861 sk->sk_prot->destroy(sk); 3862 3863 /* 3864 * Observation: when sk_common_release is called, processes have 3865 * no access to socket. But net still has. 3866 * Step one, detach it from networking: 3867 * 3868 * A. Remove from hash tables. 3869 */ 3870 3871 sk->sk_prot->unhash(sk); 3872 3873 /* 3874 * In this point socket cannot receive new packets, but it is possible 3875 * that some packets are in flight because some CPU runs receiver and 3876 * did hash table lookup before we unhashed socket. They will achieve 3877 * receive queue and will be purged by socket destructor. 3878 * 3879 * Also we still have packets pending on receive queue and probably, 3880 * our own packets waiting in device queues. sock_destroy will drain 3881 * receive queue, but transmitted packets will delay socket destruction 3882 * until the last reference will be released. 3883 */ 3884 3885 sock_orphan(sk); 3886 3887 xfrm_sk_free_policy(sk); 3888 3889 sock_put(sk); 3890 } 3891 EXPORT_SYMBOL(sk_common_release); 3892 3893 void sk_get_meminfo(const struct sock *sk, u32 *mem) 3894 { 3895 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); 3896 3897 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 3898 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf); 3899 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 3900 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf); 3901 mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk); 3902 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued); 3903 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 3904 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len); 3905 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); 3906 } 3907 3908 #ifdef CONFIG_PROC_FS 3909 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 3910 3911 int sock_prot_inuse_get(struct net *net, struct proto *prot) 3912 { 3913 int cpu, idx = prot->inuse_idx; 3914 int res = 0; 3915 3916 for_each_possible_cpu(cpu) 3917 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx]; 3918 3919 return res >= 0 ? res : 0; 3920 } 3921 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 3922 3923 int sock_inuse_get(struct net *net) 3924 { 3925 int cpu, res = 0; 3926 3927 for_each_possible_cpu(cpu) 3928 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all; 3929 3930 return res; 3931 } 3932 3933 EXPORT_SYMBOL_GPL(sock_inuse_get); 3934 3935 static int __net_init sock_inuse_init_net(struct net *net) 3936 { 3937 net->core.prot_inuse = alloc_percpu(struct prot_inuse); 3938 if (net->core.prot_inuse == NULL) 3939 return -ENOMEM; 3940 return 0; 3941 } 3942 3943 static void __net_exit sock_inuse_exit_net(struct net *net) 3944 { 3945 free_percpu(net->core.prot_inuse); 3946 } 3947 3948 static struct pernet_operations net_inuse_ops = { 3949 .init = sock_inuse_init_net, 3950 .exit = sock_inuse_exit_net, 3951 }; 3952 3953 static __init int net_inuse_init(void) 3954 { 3955 if (register_pernet_subsys(&net_inuse_ops)) 3956 panic("Cannot initialize net inuse counters"); 3957 3958 return 0; 3959 } 3960 3961 core_initcall(net_inuse_init); 3962 3963 static int assign_proto_idx(struct proto *prot) 3964 { 3965 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 3966 3967 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 3968 pr_err("PROTO_INUSE_NR exhausted\n"); 3969 return -ENOSPC; 3970 } 3971 3972 set_bit(prot->inuse_idx, proto_inuse_idx); 3973 return 0; 3974 } 3975 3976 static void release_proto_idx(struct proto *prot) 3977 { 3978 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 3979 clear_bit(prot->inuse_idx, proto_inuse_idx); 3980 } 3981 #else 3982 static inline int assign_proto_idx(struct proto *prot) 3983 { 3984 return 0; 3985 } 3986 3987 static inline void release_proto_idx(struct proto *prot) 3988 { 3989 } 3990 3991 #endif 3992 3993 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot) 3994 { 3995 if (!twsk_prot) 3996 return; 3997 kfree(twsk_prot->twsk_slab_name); 3998 twsk_prot->twsk_slab_name = NULL; 3999 kmem_cache_destroy(twsk_prot->twsk_slab); 4000 twsk_prot->twsk_slab = NULL; 4001 } 4002 4003 static int tw_prot_init(const struct proto *prot) 4004 { 4005 struct timewait_sock_ops *twsk_prot = prot->twsk_prot; 4006 4007 if (!twsk_prot) 4008 return 0; 4009 4010 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", 4011 prot->name); 4012 if (!twsk_prot->twsk_slab_name) 4013 return -ENOMEM; 4014 4015 twsk_prot->twsk_slab = 4016 kmem_cache_create(twsk_prot->twsk_slab_name, 4017 twsk_prot->twsk_obj_size, 0, 4018 SLAB_ACCOUNT | prot->slab_flags, 4019 NULL); 4020 if (!twsk_prot->twsk_slab) { 4021 pr_crit("%s: Can't create timewait sock SLAB cache!\n", 4022 prot->name); 4023 return -ENOMEM; 4024 } 4025 4026 return 0; 4027 } 4028 4029 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 4030 { 4031 if (!rsk_prot) 4032 return; 4033 kfree(rsk_prot->slab_name); 4034 rsk_prot->slab_name = NULL; 4035 kmem_cache_destroy(rsk_prot->slab); 4036 rsk_prot->slab = NULL; 4037 } 4038 4039 static int req_prot_init(const struct proto *prot) 4040 { 4041 struct request_sock_ops *rsk_prot = prot->rsk_prot; 4042 4043 if (!rsk_prot) 4044 return 0; 4045 4046 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 4047 prot->name); 4048 if (!rsk_prot->slab_name) 4049 return -ENOMEM; 4050 4051 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 4052 rsk_prot->obj_size, 0, 4053 SLAB_ACCOUNT | prot->slab_flags, 4054 NULL); 4055 4056 if (!rsk_prot->slab) { 4057 pr_crit("%s: Can't create request sock SLAB cache!\n", 4058 prot->name); 4059 return -ENOMEM; 4060 } 4061 return 0; 4062 } 4063 4064 int proto_register(struct proto *prot, int alloc_slab) 4065 { 4066 int ret = -ENOBUFS; 4067 4068 if (prot->memory_allocated && !prot->sysctl_mem) { 4069 pr_err("%s: missing sysctl_mem\n", prot->name); 4070 return -EINVAL; 4071 } 4072 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) { 4073 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name); 4074 return -EINVAL; 4075 } 4076 if (alloc_slab) { 4077 prot->slab = kmem_cache_create_usercopy(prot->name, 4078 prot->obj_size, 0, 4079 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | 4080 prot->slab_flags, 4081 prot->useroffset, prot->usersize, 4082 NULL); 4083 4084 if (prot->slab == NULL) { 4085 pr_crit("%s: Can't create sock SLAB cache!\n", 4086 prot->name); 4087 goto out; 4088 } 4089 4090 if (req_prot_init(prot)) 4091 goto out_free_request_sock_slab; 4092 4093 if (tw_prot_init(prot)) 4094 goto out_free_timewait_sock_slab; 4095 } 4096 4097 mutex_lock(&proto_list_mutex); 4098 ret = assign_proto_idx(prot); 4099 if (ret) { 4100 mutex_unlock(&proto_list_mutex); 4101 goto out_free_timewait_sock_slab; 4102 } 4103 list_add(&prot->node, &proto_list); 4104 mutex_unlock(&proto_list_mutex); 4105 return ret; 4106 4107 out_free_timewait_sock_slab: 4108 if (alloc_slab) 4109 tw_prot_cleanup(prot->twsk_prot); 4110 out_free_request_sock_slab: 4111 if (alloc_slab) { 4112 req_prot_cleanup(prot->rsk_prot); 4113 4114 kmem_cache_destroy(prot->slab); 4115 prot->slab = NULL; 4116 } 4117 out: 4118 return ret; 4119 } 4120 EXPORT_SYMBOL(proto_register); 4121 4122 void proto_unregister(struct proto *prot) 4123 { 4124 mutex_lock(&proto_list_mutex); 4125 release_proto_idx(prot); 4126 list_del(&prot->node); 4127 mutex_unlock(&proto_list_mutex); 4128 4129 kmem_cache_destroy(prot->slab); 4130 prot->slab = NULL; 4131 4132 req_prot_cleanup(prot->rsk_prot); 4133 tw_prot_cleanup(prot->twsk_prot); 4134 } 4135 EXPORT_SYMBOL(proto_unregister); 4136 4137 int sock_load_diag_module(int family, int protocol) 4138 { 4139 if (!protocol) { 4140 if (!sock_is_registered(family)) 4141 return -ENOENT; 4142 4143 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 4144 NETLINK_SOCK_DIAG, family); 4145 } 4146 4147 #ifdef CONFIG_INET 4148 if (family == AF_INET && 4149 protocol != IPPROTO_RAW && 4150 protocol < MAX_INET_PROTOS && 4151 !rcu_access_pointer(inet_protos[protocol])) 4152 return -ENOENT; 4153 #endif 4154 4155 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK, 4156 NETLINK_SOCK_DIAG, family, protocol); 4157 } 4158 EXPORT_SYMBOL(sock_load_diag_module); 4159 4160 #ifdef CONFIG_PROC_FS 4161 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 4162 __acquires(proto_list_mutex) 4163 { 4164 mutex_lock(&proto_list_mutex); 4165 return seq_list_start_head(&proto_list, *pos); 4166 } 4167 4168 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4169 { 4170 return seq_list_next(v, &proto_list, pos); 4171 } 4172 4173 static void proto_seq_stop(struct seq_file *seq, void *v) 4174 __releases(proto_list_mutex) 4175 { 4176 mutex_unlock(&proto_list_mutex); 4177 } 4178 4179 static char proto_method_implemented(const void *method) 4180 { 4181 return method == NULL ? 'n' : 'y'; 4182 } 4183 static long sock_prot_memory_allocated(struct proto *proto) 4184 { 4185 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 4186 } 4187 4188 static const char *sock_prot_memory_pressure(struct proto *proto) 4189 { 4190 return proto->memory_pressure != NULL ? 4191 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 4192 } 4193 4194 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 4195 { 4196 4197 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 4198 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 4199 proto->name, 4200 proto->obj_size, 4201 sock_prot_inuse_get(seq_file_net(seq), proto), 4202 sock_prot_memory_allocated(proto), 4203 sock_prot_memory_pressure(proto), 4204 proto->max_header, 4205 proto->slab == NULL ? "no" : "yes", 4206 module_name(proto->owner), 4207 proto_method_implemented(proto->close), 4208 proto_method_implemented(proto->connect), 4209 proto_method_implemented(proto->disconnect), 4210 proto_method_implemented(proto->accept), 4211 proto_method_implemented(proto->ioctl), 4212 proto_method_implemented(proto->init), 4213 proto_method_implemented(proto->destroy), 4214 proto_method_implemented(proto->shutdown), 4215 proto_method_implemented(proto->setsockopt), 4216 proto_method_implemented(proto->getsockopt), 4217 proto_method_implemented(proto->sendmsg), 4218 proto_method_implemented(proto->recvmsg), 4219 proto_method_implemented(proto->bind), 4220 proto_method_implemented(proto->backlog_rcv), 4221 proto_method_implemented(proto->hash), 4222 proto_method_implemented(proto->unhash), 4223 proto_method_implemented(proto->get_port), 4224 proto_method_implemented(proto->enter_memory_pressure)); 4225 } 4226 4227 static int proto_seq_show(struct seq_file *seq, void *v) 4228 { 4229 if (v == &proto_list) 4230 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 4231 "protocol", 4232 "size", 4233 "sockets", 4234 "memory", 4235 "press", 4236 "maxhdr", 4237 "slab", 4238 "module", 4239 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n"); 4240 else 4241 proto_seq_printf(seq, list_entry(v, struct proto, node)); 4242 return 0; 4243 } 4244 4245 static const struct seq_operations proto_seq_ops = { 4246 .start = proto_seq_start, 4247 .next = proto_seq_next, 4248 .stop = proto_seq_stop, 4249 .show = proto_seq_show, 4250 }; 4251 4252 static __net_init int proto_init_net(struct net *net) 4253 { 4254 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops, 4255 sizeof(struct seq_net_private))) 4256 return -ENOMEM; 4257 4258 return 0; 4259 } 4260 4261 static __net_exit void proto_exit_net(struct net *net) 4262 { 4263 remove_proc_entry("protocols", net->proc_net); 4264 } 4265 4266 4267 static __net_initdata struct pernet_operations proto_net_ops = { 4268 .init = proto_init_net, 4269 .exit = proto_exit_net, 4270 }; 4271 4272 static int __init proto_init(void) 4273 { 4274 return register_pernet_subsys(&proto_net_ops); 4275 } 4276 4277 subsys_initcall(proto_init); 4278 4279 #endif /* PROC_FS */ 4280 4281 #ifdef CONFIG_NET_RX_BUSY_POLL 4282 bool sk_busy_loop_end(void *p, unsigned long start_time) 4283 { 4284 struct sock *sk = p; 4285 4286 if (!skb_queue_empty_lockless(&sk->sk_receive_queue)) 4287 return true; 4288 4289 if (sk_is_udp(sk) && 4290 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue)) 4291 return true; 4292 4293 return sk_busy_loop_timeout(sk, start_time); 4294 } 4295 EXPORT_SYMBOL(sk_busy_loop_end); 4296 #endif /* CONFIG_NET_RX_BUSY_POLL */ 4297 4298 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len) 4299 { 4300 if (!sk->sk_prot->bind_add) 4301 return -EOPNOTSUPP; 4302 return sk->sk_prot->bind_add(sk, addr, addr_len); 4303 } 4304 EXPORT_SYMBOL(sock_bind_add); 4305 4306 /* Copy 'size' bytes from userspace and return `size` back to userspace */ 4307 int sock_ioctl_inout(struct sock *sk, unsigned int cmd, 4308 void __user *arg, void *karg, size_t size) 4309 { 4310 int ret; 4311 4312 if (copy_from_user(karg, arg, size)) 4313 return -EFAULT; 4314 4315 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg); 4316 if (ret) 4317 return ret; 4318 4319 if (copy_to_user(arg, karg, size)) 4320 return -EFAULT; 4321 4322 return 0; 4323 } 4324 EXPORT_SYMBOL(sock_ioctl_inout); 4325 4326 /* This is the most common ioctl prep function, where the result (4 bytes) is 4327 * copied back to userspace if the ioctl() returns successfully. No input is 4328 * copied from userspace as input argument. 4329 */ 4330 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg) 4331 { 4332 int ret, karg = 0; 4333 4334 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg); 4335 if (ret) 4336 return ret; 4337 4338 return put_user(karg, (int __user *)arg); 4339 } 4340 4341 /* A wrapper around sock ioctls, which copies the data from userspace 4342 * (depending on the protocol/ioctl), and copies back the result to userspace. 4343 * The main motivation for this function is to pass kernel memory to the 4344 * protocol ioctl callbacks, instead of userspace memory. 4345 */ 4346 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg) 4347 { 4348 int rc = 1; 4349 4350 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET) 4351 rc = ipmr_sk_ioctl(sk, cmd, arg); 4352 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6) 4353 rc = ip6mr_sk_ioctl(sk, cmd, arg); 4354 else if (sk_is_phonet(sk)) 4355 rc = phonet_sk_ioctl(sk, cmd, arg); 4356 4357 /* If ioctl was processed, returns its value */ 4358 if (rc <= 0) 4359 return rc; 4360 4361 /* Otherwise call the default handler */ 4362 return sock_ioctl_out(sk, cmd, arg); 4363 } 4364 EXPORT_SYMBOL(sk_ioctl); 4365 4366 static int __init sock_struct_check(void) 4367 { 4368 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops); 4369 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off); 4370 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue); 4371 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue); 4372 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog); 4373 4374 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst); 4375 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex); 4376 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie); 4377 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf); 4378 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter); 4379 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq); 4380 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready); 4381 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo); 4382 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat); 4383 4384 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err); 4385 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket); 4386 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg); 4387 4388 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock); 4389 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem); 4390 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc); 4391 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags); 4392 4393 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc); 4394 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc); 4395 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_sndbuf); 4396 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued); 4397 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc); 4398 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags); 4399 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head); 4400 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue); 4401 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending); 4402 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm); 4403 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status); 4404 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag); 4405 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer); 4406 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate); 4407 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey); 4408 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey); 4409 4410 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate); 4411 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo); 4412 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority); 4413 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark); 4414 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache); 4415 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps); 4416 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type); 4417 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size); 4418 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation); 4419 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash); 4420 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs); 4421 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift); 4422 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag); 4423 return 0; 4424 } 4425 4426 core_initcall(sock_struct_check); 4427