1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Generic socket support routines. Memory allocators, socket lock/release 7 * handler for protocols to use and generic option handler. 8 * 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 * This program is free software; you can redistribute it and/or 87 * modify it under the terms of the GNU General Public License 88 * as published by the Free Software Foundation; either version 89 * 2 of the License, or (at your option) any later version. 90 */ 91 92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 93 94 #include <linux/capability.h> 95 #include <linux/errno.h> 96 #include <linux/errqueue.h> 97 #include <linux/types.h> 98 #include <linux/socket.h> 99 #include <linux/in.h> 100 #include <linux/kernel.h> 101 #include <linux/module.h> 102 #include <linux/proc_fs.h> 103 #include <linux/seq_file.h> 104 #include <linux/sched.h> 105 #include <linux/timer.h> 106 #include <linux/string.h> 107 #include <linux/sockios.h> 108 #include <linux/net.h> 109 #include <linux/mm.h> 110 #include <linux/slab.h> 111 #include <linux/interrupt.h> 112 #include <linux/poll.h> 113 #include <linux/tcp.h> 114 #include <linux/init.h> 115 #include <linux/highmem.h> 116 #include <linux/user_namespace.h> 117 #include <linux/static_key.h> 118 #include <linux/memcontrol.h> 119 #include <linux/prefetch.h> 120 121 #include <asm/uaccess.h> 122 123 #include <linux/netdevice.h> 124 #include <net/protocol.h> 125 #include <linux/skbuff.h> 126 #include <net/net_namespace.h> 127 #include <net/request_sock.h> 128 #include <net/sock.h> 129 #include <linux/net_tstamp.h> 130 #include <net/xfrm.h> 131 #include <linux/ipsec.h> 132 #include <net/cls_cgroup.h> 133 #include <net/netprio_cgroup.h> 134 #include <linux/sock_diag.h> 135 136 #include <linux/filter.h> 137 138 #include <trace/events/sock.h> 139 140 #ifdef CONFIG_INET 141 #include <net/tcp.h> 142 #endif 143 144 #include <net/busy_poll.h> 145 146 static DEFINE_MUTEX(proto_list_mutex); 147 static LIST_HEAD(proto_list); 148 149 /** 150 * sk_ns_capable - General socket capability test 151 * @sk: Socket to use a capability on or through 152 * @user_ns: The user namespace of the capability to use 153 * @cap: The capability to use 154 * 155 * Test to see if the opener of the socket had when the socket was 156 * created and the current process has the capability @cap in the user 157 * namespace @user_ns. 158 */ 159 bool sk_ns_capable(const struct sock *sk, 160 struct user_namespace *user_ns, int cap) 161 { 162 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 163 ns_capable(user_ns, cap); 164 } 165 EXPORT_SYMBOL(sk_ns_capable); 166 167 /** 168 * sk_capable - Socket global capability test 169 * @sk: Socket to use a capability on or through 170 * @cap: The global capability to use 171 * 172 * Test to see if the opener of the socket had when the socket was 173 * created and the current process has the capability @cap in all user 174 * namespaces. 175 */ 176 bool sk_capable(const struct sock *sk, int cap) 177 { 178 return sk_ns_capable(sk, &init_user_ns, cap); 179 } 180 EXPORT_SYMBOL(sk_capable); 181 182 /** 183 * sk_net_capable - Network namespace socket capability test 184 * @sk: Socket to use a capability on or through 185 * @cap: The capability to use 186 * 187 * Test to see if the opener of the socket had when the socket was created 188 * and the current process has the capability @cap over the network namespace 189 * the socket is a member of. 190 */ 191 bool sk_net_capable(const struct sock *sk, int cap) 192 { 193 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 194 } 195 EXPORT_SYMBOL(sk_net_capable); 196 197 198 #ifdef CONFIG_MEMCG_KMEM 199 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 200 { 201 struct proto *proto; 202 int ret = 0; 203 204 mutex_lock(&proto_list_mutex); 205 list_for_each_entry(proto, &proto_list, node) { 206 if (proto->init_cgroup) { 207 ret = proto->init_cgroup(memcg, ss); 208 if (ret) 209 goto out; 210 } 211 } 212 213 mutex_unlock(&proto_list_mutex); 214 return ret; 215 out: 216 list_for_each_entry_continue_reverse(proto, &proto_list, node) 217 if (proto->destroy_cgroup) 218 proto->destroy_cgroup(memcg); 219 mutex_unlock(&proto_list_mutex); 220 return ret; 221 } 222 223 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 224 { 225 struct proto *proto; 226 227 mutex_lock(&proto_list_mutex); 228 list_for_each_entry_reverse(proto, &proto_list, node) 229 if (proto->destroy_cgroup) 230 proto->destroy_cgroup(memcg); 231 mutex_unlock(&proto_list_mutex); 232 } 233 #endif 234 235 /* 236 * Each address family might have different locking rules, so we have 237 * one slock key per address family: 238 */ 239 static struct lock_class_key af_family_keys[AF_MAX]; 240 static struct lock_class_key af_family_slock_keys[AF_MAX]; 241 242 #if defined(CONFIG_MEMCG_KMEM) 243 struct static_key memcg_socket_limit_enabled; 244 EXPORT_SYMBOL(memcg_socket_limit_enabled); 245 #endif 246 247 /* 248 * Make lock validator output more readable. (we pre-construct these 249 * strings build-time, so that runtime initialization of socket 250 * locks is fast): 251 */ 252 static const char *const af_family_key_strings[AF_MAX+1] = { 253 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 254 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 255 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 256 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 257 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 258 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 259 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 260 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 261 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 262 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 263 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 264 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 265 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 266 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX" 267 }; 268 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 269 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 270 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 271 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 272 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 273 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 274 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 275 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 276 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 277 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 278 "slock-27" , "slock-28" , "slock-AF_CAN" , 279 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 280 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 281 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 282 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX" 283 }; 284 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 285 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 286 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 287 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 288 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 289 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 290 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 291 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 292 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 293 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 294 "clock-27" , "clock-28" , "clock-AF_CAN" , 295 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 296 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 297 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 298 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX" 299 }; 300 301 /* 302 * sk_callback_lock locking rules are per-address-family, 303 * so split the lock classes by using a per-AF key: 304 */ 305 static struct lock_class_key af_callback_keys[AF_MAX]; 306 307 /* Take into consideration the size of the struct sk_buff overhead in the 308 * determination of these values, since that is non-constant across 309 * platforms. This makes socket queueing behavior and performance 310 * not depend upon such differences. 311 */ 312 #define _SK_MEM_PACKETS 256 313 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 314 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 315 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 316 317 /* Run time adjustable parameters. */ 318 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 319 EXPORT_SYMBOL(sysctl_wmem_max); 320 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 321 EXPORT_SYMBOL(sysctl_rmem_max); 322 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 323 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 324 325 /* Maximal space eaten by iovec or ancillary data plus some space */ 326 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 327 EXPORT_SYMBOL(sysctl_optmem_max); 328 329 int sysctl_tstamp_allow_data __read_mostly = 1; 330 331 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 332 EXPORT_SYMBOL_GPL(memalloc_socks); 333 334 /** 335 * sk_set_memalloc - sets %SOCK_MEMALLOC 336 * @sk: socket to set it on 337 * 338 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 339 * It's the responsibility of the admin to adjust min_free_kbytes 340 * to meet the requirements 341 */ 342 void sk_set_memalloc(struct sock *sk) 343 { 344 sock_set_flag(sk, SOCK_MEMALLOC); 345 sk->sk_allocation |= __GFP_MEMALLOC; 346 static_key_slow_inc(&memalloc_socks); 347 } 348 EXPORT_SYMBOL_GPL(sk_set_memalloc); 349 350 void sk_clear_memalloc(struct sock *sk) 351 { 352 sock_reset_flag(sk, SOCK_MEMALLOC); 353 sk->sk_allocation &= ~__GFP_MEMALLOC; 354 static_key_slow_dec(&memalloc_socks); 355 356 /* 357 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 358 * progress of swapping. SOCK_MEMALLOC may be cleared while 359 * it has rmem allocations due to the last swapfile being deactivated 360 * but there is a risk that the socket is unusable due to exceeding 361 * the rmem limits. Reclaim the reserves and obey rmem limits again. 362 */ 363 sk_mem_reclaim(sk); 364 } 365 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 366 367 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 368 { 369 int ret; 370 unsigned long pflags = current->flags; 371 372 /* these should have been dropped before queueing */ 373 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 374 375 current->flags |= PF_MEMALLOC; 376 ret = sk->sk_backlog_rcv(sk, skb); 377 tsk_restore_flags(current, pflags, PF_MEMALLOC); 378 379 return ret; 380 } 381 EXPORT_SYMBOL(__sk_backlog_rcv); 382 383 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 384 { 385 struct timeval tv; 386 387 if (optlen < sizeof(tv)) 388 return -EINVAL; 389 if (copy_from_user(&tv, optval, sizeof(tv))) 390 return -EFAULT; 391 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 392 return -EDOM; 393 394 if (tv.tv_sec < 0) { 395 static int warned __read_mostly; 396 397 *timeo_p = 0; 398 if (warned < 10 && net_ratelimit()) { 399 warned++; 400 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 401 __func__, current->comm, task_pid_nr(current)); 402 } 403 return 0; 404 } 405 *timeo_p = MAX_SCHEDULE_TIMEOUT; 406 if (tv.tv_sec == 0 && tv.tv_usec == 0) 407 return 0; 408 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 409 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 410 return 0; 411 } 412 413 static void sock_warn_obsolete_bsdism(const char *name) 414 { 415 static int warned; 416 static char warncomm[TASK_COMM_LEN]; 417 if (strcmp(warncomm, current->comm) && warned < 5) { 418 strcpy(warncomm, current->comm); 419 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 420 warncomm, name); 421 warned++; 422 } 423 } 424 425 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 426 427 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 428 { 429 if (sk->sk_flags & flags) { 430 sk->sk_flags &= ~flags; 431 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 432 net_disable_timestamp(); 433 } 434 } 435 436 437 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 438 { 439 int err; 440 unsigned long flags; 441 struct sk_buff_head *list = &sk->sk_receive_queue; 442 443 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 444 atomic_inc(&sk->sk_drops); 445 trace_sock_rcvqueue_full(sk, skb); 446 return -ENOMEM; 447 } 448 449 err = sk_filter(sk, skb); 450 if (err) 451 return err; 452 453 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 454 atomic_inc(&sk->sk_drops); 455 return -ENOBUFS; 456 } 457 458 skb->dev = NULL; 459 skb_set_owner_r(skb, sk); 460 461 /* we escape from rcu protected region, make sure we dont leak 462 * a norefcounted dst 463 */ 464 skb_dst_force(skb); 465 466 spin_lock_irqsave(&list->lock, flags); 467 sock_skb_set_dropcount(sk, skb); 468 __skb_queue_tail(list, skb); 469 spin_unlock_irqrestore(&list->lock, flags); 470 471 if (!sock_flag(sk, SOCK_DEAD)) 472 sk->sk_data_ready(sk); 473 return 0; 474 } 475 EXPORT_SYMBOL(sock_queue_rcv_skb); 476 477 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 478 { 479 int rc = NET_RX_SUCCESS; 480 481 if (sk_filter(sk, skb)) 482 goto discard_and_relse; 483 484 skb->dev = NULL; 485 486 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 487 atomic_inc(&sk->sk_drops); 488 goto discard_and_relse; 489 } 490 if (nested) 491 bh_lock_sock_nested(sk); 492 else 493 bh_lock_sock(sk); 494 if (!sock_owned_by_user(sk)) { 495 /* 496 * trylock + unlock semantics: 497 */ 498 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 499 500 rc = sk_backlog_rcv(sk, skb); 501 502 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 503 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 504 bh_unlock_sock(sk); 505 atomic_inc(&sk->sk_drops); 506 goto discard_and_relse; 507 } 508 509 bh_unlock_sock(sk); 510 out: 511 sock_put(sk); 512 return rc; 513 discard_and_relse: 514 kfree_skb(skb); 515 goto out; 516 } 517 EXPORT_SYMBOL(sk_receive_skb); 518 519 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 520 { 521 struct dst_entry *dst = __sk_dst_get(sk); 522 523 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 524 sk_tx_queue_clear(sk); 525 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 526 dst_release(dst); 527 return NULL; 528 } 529 530 return dst; 531 } 532 EXPORT_SYMBOL(__sk_dst_check); 533 534 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 535 { 536 struct dst_entry *dst = sk_dst_get(sk); 537 538 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 539 sk_dst_reset(sk); 540 dst_release(dst); 541 return NULL; 542 } 543 544 return dst; 545 } 546 EXPORT_SYMBOL(sk_dst_check); 547 548 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 549 int optlen) 550 { 551 int ret = -ENOPROTOOPT; 552 #ifdef CONFIG_NETDEVICES 553 struct net *net = sock_net(sk); 554 char devname[IFNAMSIZ]; 555 int index; 556 557 /* Sorry... */ 558 ret = -EPERM; 559 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 560 goto out; 561 562 ret = -EINVAL; 563 if (optlen < 0) 564 goto out; 565 566 /* Bind this socket to a particular device like "eth0", 567 * as specified in the passed interface name. If the 568 * name is "" or the option length is zero the socket 569 * is not bound. 570 */ 571 if (optlen > IFNAMSIZ - 1) 572 optlen = IFNAMSIZ - 1; 573 memset(devname, 0, sizeof(devname)); 574 575 ret = -EFAULT; 576 if (copy_from_user(devname, optval, optlen)) 577 goto out; 578 579 index = 0; 580 if (devname[0] != '\0') { 581 struct net_device *dev; 582 583 rcu_read_lock(); 584 dev = dev_get_by_name_rcu(net, devname); 585 if (dev) 586 index = dev->ifindex; 587 rcu_read_unlock(); 588 ret = -ENODEV; 589 if (!dev) 590 goto out; 591 } 592 593 lock_sock(sk); 594 sk->sk_bound_dev_if = index; 595 sk_dst_reset(sk); 596 release_sock(sk); 597 598 ret = 0; 599 600 out: 601 #endif 602 603 return ret; 604 } 605 606 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 607 int __user *optlen, int len) 608 { 609 int ret = -ENOPROTOOPT; 610 #ifdef CONFIG_NETDEVICES 611 struct net *net = sock_net(sk); 612 char devname[IFNAMSIZ]; 613 614 if (sk->sk_bound_dev_if == 0) { 615 len = 0; 616 goto zero; 617 } 618 619 ret = -EINVAL; 620 if (len < IFNAMSIZ) 621 goto out; 622 623 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 624 if (ret) 625 goto out; 626 627 len = strlen(devname) + 1; 628 629 ret = -EFAULT; 630 if (copy_to_user(optval, devname, len)) 631 goto out; 632 633 zero: 634 ret = -EFAULT; 635 if (put_user(len, optlen)) 636 goto out; 637 638 ret = 0; 639 640 out: 641 #endif 642 643 return ret; 644 } 645 646 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 647 { 648 if (valbool) 649 sock_set_flag(sk, bit); 650 else 651 sock_reset_flag(sk, bit); 652 } 653 654 bool sk_mc_loop(struct sock *sk) 655 { 656 if (dev_recursion_level()) 657 return false; 658 if (!sk) 659 return true; 660 switch (sk->sk_family) { 661 case AF_INET: 662 return inet_sk(sk)->mc_loop; 663 #if IS_ENABLED(CONFIG_IPV6) 664 case AF_INET6: 665 return inet6_sk(sk)->mc_loop; 666 #endif 667 } 668 WARN_ON(1); 669 return true; 670 } 671 EXPORT_SYMBOL(sk_mc_loop); 672 673 /* 674 * This is meant for all protocols to use and covers goings on 675 * at the socket level. Everything here is generic. 676 */ 677 678 int sock_setsockopt(struct socket *sock, int level, int optname, 679 char __user *optval, unsigned int optlen) 680 { 681 struct sock *sk = sock->sk; 682 int val; 683 int valbool; 684 struct linger ling; 685 int ret = 0; 686 687 /* 688 * Options without arguments 689 */ 690 691 if (optname == SO_BINDTODEVICE) 692 return sock_setbindtodevice(sk, optval, optlen); 693 694 if (optlen < sizeof(int)) 695 return -EINVAL; 696 697 if (get_user(val, (int __user *)optval)) 698 return -EFAULT; 699 700 valbool = val ? 1 : 0; 701 702 lock_sock(sk); 703 704 switch (optname) { 705 case SO_DEBUG: 706 if (val && !capable(CAP_NET_ADMIN)) 707 ret = -EACCES; 708 else 709 sock_valbool_flag(sk, SOCK_DBG, valbool); 710 break; 711 case SO_REUSEADDR: 712 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 713 break; 714 case SO_REUSEPORT: 715 sk->sk_reuseport = valbool; 716 break; 717 case SO_TYPE: 718 case SO_PROTOCOL: 719 case SO_DOMAIN: 720 case SO_ERROR: 721 ret = -ENOPROTOOPT; 722 break; 723 case SO_DONTROUTE: 724 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 725 break; 726 case SO_BROADCAST: 727 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 728 break; 729 case SO_SNDBUF: 730 /* Don't error on this BSD doesn't and if you think 731 * about it this is right. Otherwise apps have to 732 * play 'guess the biggest size' games. RCVBUF/SNDBUF 733 * are treated in BSD as hints 734 */ 735 val = min_t(u32, val, sysctl_wmem_max); 736 set_sndbuf: 737 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 738 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 739 /* Wake up sending tasks if we upped the value. */ 740 sk->sk_write_space(sk); 741 break; 742 743 case SO_SNDBUFFORCE: 744 if (!capable(CAP_NET_ADMIN)) { 745 ret = -EPERM; 746 break; 747 } 748 goto set_sndbuf; 749 750 case SO_RCVBUF: 751 /* Don't error on this BSD doesn't and if you think 752 * about it this is right. Otherwise apps have to 753 * play 'guess the biggest size' games. RCVBUF/SNDBUF 754 * are treated in BSD as hints 755 */ 756 val = min_t(u32, val, sysctl_rmem_max); 757 set_rcvbuf: 758 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 759 /* 760 * We double it on the way in to account for 761 * "struct sk_buff" etc. overhead. Applications 762 * assume that the SO_RCVBUF setting they make will 763 * allow that much actual data to be received on that 764 * socket. 765 * 766 * Applications are unaware that "struct sk_buff" and 767 * other overheads allocate from the receive buffer 768 * during socket buffer allocation. 769 * 770 * And after considering the possible alternatives, 771 * returning the value we actually used in getsockopt 772 * is the most desirable behavior. 773 */ 774 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 775 break; 776 777 case SO_RCVBUFFORCE: 778 if (!capable(CAP_NET_ADMIN)) { 779 ret = -EPERM; 780 break; 781 } 782 goto set_rcvbuf; 783 784 case SO_KEEPALIVE: 785 #ifdef CONFIG_INET 786 if (sk->sk_protocol == IPPROTO_TCP && 787 sk->sk_type == SOCK_STREAM) 788 tcp_set_keepalive(sk, valbool); 789 #endif 790 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 791 break; 792 793 case SO_OOBINLINE: 794 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 795 break; 796 797 case SO_NO_CHECK: 798 sk->sk_no_check_tx = valbool; 799 break; 800 801 case SO_PRIORITY: 802 if ((val >= 0 && val <= 6) || 803 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 804 sk->sk_priority = val; 805 else 806 ret = -EPERM; 807 break; 808 809 case SO_LINGER: 810 if (optlen < sizeof(ling)) { 811 ret = -EINVAL; /* 1003.1g */ 812 break; 813 } 814 if (copy_from_user(&ling, optval, sizeof(ling))) { 815 ret = -EFAULT; 816 break; 817 } 818 if (!ling.l_onoff) 819 sock_reset_flag(sk, SOCK_LINGER); 820 else { 821 #if (BITS_PER_LONG == 32) 822 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 823 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 824 else 825 #endif 826 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 827 sock_set_flag(sk, SOCK_LINGER); 828 } 829 break; 830 831 case SO_BSDCOMPAT: 832 sock_warn_obsolete_bsdism("setsockopt"); 833 break; 834 835 case SO_PASSCRED: 836 if (valbool) 837 set_bit(SOCK_PASSCRED, &sock->flags); 838 else 839 clear_bit(SOCK_PASSCRED, &sock->flags); 840 break; 841 842 case SO_TIMESTAMP: 843 case SO_TIMESTAMPNS: 844 if (valbool) { 845 if (optname == SO_TIMESTAMP) 846 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 847 else 848 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 849 sock_set_flag(sk, SOCK_RCVTSTAMP); 850 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 851 } else { 852 sock_reset_flag(sk, SOCK_RCVTSTAMP); 853 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 854 } 855 break; 856 857 case SO_TIMESTAMPING: 858 if (val & ~SOF_TIMESTAMPING_MASK) { 859 ret = -EINVAL; 860 break; 861 } 862 863 if (val & SOF_TIMESTAMPING_OPT_ID && 864 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 865 if (sk->sk_protocol == IPPROTO_TCP) { 866 if (sk->sk_state != TCP_ESTABLISHED) { 867 ret = -EINVAL; 868 break; 869 } 870 sk->sk_tskey = tcp_sk(sk)->snd_una; 871 } else { 872 sk->sk_tskey = 0; 873 } 874 } 875 sk->sk_tsflags = val; 876 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 877 sock_enable_timestamp(sk, 878 SOCK_TIMESTAMPING_RX_SOFTWARE); 879 else 880 sock_disable_timestamp(sk, 881 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 882 break; 883 884 case SO_RCVLOWAT: 885 if (val < 0) 886 val = INT_MAX; 887 sk->sk_rcvlowat = val ? : 1; 888 break; 889 890 case SO_RCVTIMEO: 891 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 892 break; 893 894 case SO_SNDTIMEO: 895 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 896 break; 897 898 case SO_ATTACH_FILTER: 899 ret = -EINVAL; 900 if (optlen == sizeof(struct sock_fprog)) { 901 struct sock_fprog fprog; 902 903 ret = -EFAULT; 904 if (copy_from_user(&fprog, optval, sizeof(fprog))) 905 break; 906 907 ret = sk_attach_filter(&fprog, sk); 908 } 909 break; 910 911 case SO_ATTACH_BPF: 912 ret = -EINVAL; 913 if (optlen == sizeof(u32)) { 914 u32 ufd; 915 916 ret = -EFAULT; 917 if (copy_from_user(&ufd, optval, sizeof(ufd))) 918 break; 919 920 ret = sk_attach_bpf(ufd, sk); 921 } 922 break; 923 924 case SO_DETACH_FILTER: 925 ret = sk_detach_filter(sk); 926 break; 927 928 case SO_LOCK_FILTER: 929 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 930 ret = -EPERM; 931 else 932 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 933 break; 934 935 case SO_PASSSEC: 936 if (valbool) 937 set_bit(SOCK_PASSSEC, &sock->flags); 938 else 939 clear_bit(SOCK_PASSSEC, &sock->flags); 940 break; 941 case SO_MARK: 942 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 943 ret = -EPERM; 944 else 945 sk->sk_mark = val; 946 break; 947 948 case SO_RXQ_OVFL: 949 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 950 break; 951 952 case SO_WIFI_STATUS: 953 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 954 break; 955 956 case SO_PEEK_OFF: 957 if (sock->ops->set_peek_off) 958 ret = sock->ops->set_peek_off(sk, val); 959 else 960 ret = -EOPNOTSUPP; 961 break; 962 963 case SO_NOFCS: 964 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 965 break; 966 967 case SO_SELECT_ERR_QUEUE: 968 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 969 break; 970 971 #ifdef CONFIG_NET_RX_BUSY_POLL 972 case SO_BUSY_POLL: 973 /* allow unprivileged users to decrease the value */ 974 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 975 ret = -EPERM; 976 else { 977 if (val < 0) 978 ret = -EINVAL; 979 else 980 sk->sk_ll_usec = val; 981 } 982 break; 983 #endif 984 985 case SO_MAX_PACING_RATE: 986 sk->sk_max_pacing_rate = val; 987 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 988 sk->sk_max_pacing_rate); 989 break; 990 991 default: 992 ret = -ENOPROTOOPT; 993 break; 994 } 995 release_sock(sk); 996 return ret; 997 } 998 EXPORT_SYMBOL(sock_setsockopt); 999 1000 1001 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1002 struct ucred *ucred) 1003 { 1004 ucred->pid = pid_vnr(pid); 1005 ucred->uid = ucred->gid = -1; 1006 if (cred) { 1007 struct user_namespace *current_ns = current_user_ns(); 1008 1009 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1010 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1011 } 1012 } 1013 1014 int sock_getsockopt(struct socket *sock, int level, int optname, 1015 char __user *optval, int __user *optlen) 1016 { 1017 struct sock *sk = sock->sk; 1018 1019 union { 1020 int val; 1021 struct linger ling; 1022 struct timeval tm; 1023 } v; 1024 1025 int lv = sizeof(int); 1026 int len; 1027 1028 if (get_user(len, optlen)) 1029 return -EFAULT; 1030 if (len < 0) 1031 return -EINVAL; 1032 1033 memset(&v, 0, sizeof(v)); 1034 1035 switch (optname) { 1036 case SO_DEBUG: 1037 v.val = sock_flag(sk, SOCK_DBG); 1038 break; 1039 1040 case SO_DONTROUTE: 1041 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1042 break; 1043 1044 case SO_BROADCAST: 1045 v.val = sock_flag(sk, SOCK_BROADCAST); 1046 break; 1047 1048 case SO_SNDBUF: 1049 v.val = sk->sk_sndbuf; 1050 break; 1051 1052 case SO_RCVBUF: 1053 v.val = sk->sk_rcvbuf; 1054 break; 1055 1056 case SO_REUSEADDR: 1057 v.val = sk->sk_reuse; 1058 break; 1059 1060 case SO_REUSEPORT: 1061 v.val = sk->sk_reuseport; 1062 break; 1063 1064 case SO_KEEPALIVE: 1065 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1066 break; 1067 1068 case SO_TYPE: 1069 v.val = sk->sk_type; 1070 break; 1071 1072 case SO_PROTOCOL: 1073 v.val = sk->sk_protocol; 1074 break; 1075 1076 case SO_DOMAIN: 1077 v.val = sk->sk_family; 1078 break; 1079 1080 case SO_ERROR: 1081 v.val = -sock_error(sk); 1082 if (v.val == 0) 1083 v.val = xchg(&sk->sk_err_soft, 0); 1084 break; 1085 1086 case SO_OOBINLINE: 1087 v.val = sock_flag(sk, SOCK_URGINLINE); 1088 break; 1089 1090 case SO_NO_CHECK: 1091 v.val = sk->sk_no_check_tx; 1092 break; 1093 1094 case SO_PRIORITY: 1095 v.val = sk->sk_priority; 1096 break; 1097 1098 case SO_LINGER: 1099 lv = sizeof(v.ling); 1100 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1101 v.ling.l_linger = sk->sk_lingertime / HZ; 1102 break; 1103 1104 case SO_BSDCOMPAT: 1105 sock_warn_obsolete_bsdism("getsockopt"); 1106 break; 1107 1108 case SO_TIMESTAMP: 1109 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1110 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1111 break; 1112 1113 case SO_TIMESTAMPNS: 1114 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1115 break; 1116 1117 case SO_TIMESTAMPING: 1118 v.val = sk->sk_tsflags; 1119 break; 1120 1121 case SO_RCVTIMEO: 1122 lv = sizeof(struct timeval); 1123 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1124 v.tm.tv_sec = 0; 1125 v.tm.tv_usec = 0; 1126 } else { 1127 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1128 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1129 } 1130 break; 1131 1132 case SO_SNDTIMEO: 1133 lv = sizeof(struct timeval); 1134 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1135 v.tm.tv_sec = 0; 1136 v.tm.tv_usec = 0; 1137 } else { 1138 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1139 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1140 } 1141 break; 1142 1143 case SO_RCVLOWAT: 1144 v.val = sk->sk_rcvlowat; 1145 break; 1146 1147 case SO_SNDLOWAT: 1148 v.val = 1; 1149 break; 1150 1151 case SO_PASSCRED: 1152 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1153 break; 1154 1155 case SO_PEERCRED: 1156 { 1157 struct ucred peercred; 1158 if (len > sizeof(peercred)) 1159 len = sizeof(peercred); 1160 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1161 if (copy_to_user(optval, &peercred, len)) 1162 return -EFAULT; 1163 goto lenout; 1164 } 1165 1166 case SO_PEERNAME: 1167 { 1168 char address[128]; 1169 1170 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1171 return -ENOTCONN; 1172 if (lv < len) 1173 return -EINVAL; 1174 if (copy_to_user(optval, address, len)) 1175 return -EFAULT; 1176 goto lenout; 1177 } 1178 1179 /* Dubious BSD thing... Probably nobody even uses it, but 1180 * the UNIX standard wants it for whatever reason... -DaveM 1181 */ 1182 case SO_ACCEPTCONN: 1183 v.val = sk->sk_state == TCP_LISTEN; 1184 break; 1185 1186 case SO_PASSSEC: 1187 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1188 break; 1189 1190 case SO_PEERSEC: 1191 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1192 1193 case SO_MARK: 1194 v.val = sk->sk_mark; 1195 break; 1196 1197 case SO_RXQ_OVFL: 1198 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1199 break; 1200 1201 case SO_WIFI_STATUS: 1202 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1203 break; 1204 1205 case SO_PEEK_OFF: 1206 if (!sock->ops->set_peek_off) 1207 return -EOPNOTSUPP; 1208 1209 v.val = sk->sk_peek_off; 1210 break; 1211 case SO_NOFCS: 1212 v.val = sock_flag(sk, SOCK_NOFCS); 1213 break; 1214 1215 case SO_BINDTODEVICE: 1216 return sock_getbindtodevice(sk, optval, optlen, len); 1217 1218 case SO_GET_FILTER: 1219 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1220 if (len < 0) 1221 return len; 1222 1223 goto lenout; 1224 1225 case SO_LOCK_FILTER: 1226 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1227 break; 1228 1229 case SO_BPF_EXTENSIONS: 1230 v.val = bpf_tell_extensions(); 1231 break; 1232 1233 case SO_SELECT_ERR_QUEUE: 1234 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1235 break; 1236 1237 #ifdef CONFIG_NET_RX_BUSY_POLL 1238 case SO_BUSY_POLL: 1239 v.val = sk->sk_ll_usec; 1240 break; 1241 #endif 1242 1243 case SO_MAX_PACING_RATE: 1244 v.val = sk->sk_max_pacing_rate; 1245 break; 1246 1247 case SO_INCOMING_CPU: 1248 v.val = sk->sk_incoming_cpu; 1249 break; 1250 1251 default: 1252 /* We implement the SO_SNDLOWAT etc to not be settable 1253 * (1003.1g 7). 1254 */ 1255 return -ENOPROTOOPT; 1256 } 1257 1258 if (len > lv) 1259 len = lv; 1260 if (copy_to_user(optval, &v, len)) 1261 return -EFAULT; 1262 lenout: 1263 if (put_user(len, optlen)) 1264 return -EFAULT; 1265 return 0; 1266 } 1267 1268 /* 1269 * Initialize an sk_lock. 1270 * 1271 * (We also register the sk_lock with the lock validator.) 1272 */ 1273 static inline void sock_lock_init(struct sock *sk) 1274 { 1275 sock_lock_init_class_and_name(sk, 1276 af_family_slock_key_strings[sk->sk_family], 1277 af_family_slock_keys + sk->sk_family, 1278 af_family_key_strings[sk->sk_family], 1279 af_family_keys + sk->sk_family); 1280 } 1281 1282 /* 1283 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1284 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1285 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1286 */ 1287 static void sock_copy(struct sock *nsk, const struct sock *osk) 1288 { 1289 #ifdef CONFIG_SECURITY_NETWORK 1290 void *sptr = nsk->sk_security; 1291 #endif 1292 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1293 1294 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1295 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1296 1297 #ifdef CONFIG_SECURITY_NETWORK 1298 nsk->sk_security = sptr; 1299 security_sk_clone(osk, nsk); 1300 #endif 1301 } 1302 1303 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1304 { 1305 unsigned long nulls1, nulls2; 1306 1307 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1308 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1309 if (nulls1 > nulls2) 1310 swap(nulls1, nulls2); 1311 1312 if (nulls1 != 0) 1313 memset((char *)sk, 0, nulls1); 1314 memset((char *)sk + nulls1 + sizeof(void *), 0, 1315 nulls2 - nulls1 - sizeof(void *)); 1316 memset((char *)sk + nulls2 + sizeof(void *), 0, 1317 size - nulls2 - sizeof(void *)); 1318 } 1319 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1320 1321 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1322 int family) 1323 { 1324 struct sock *sk; 1325 struct kmem_cache *slab; 1326 1327 slab = prot->slab; 1328 if (slab != NULL) { 1329 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1330 if (!sk) 1331 return sk; 1332 if (priority & __GFP_ZERO) { 1333 if (prot->clear_sk) 1334 prot->clear_sk(sk, prot->obj_size); 1335 else 1336 sk_prot_clear_nulls(sk, prot->obj_size); 1337 } 1338 } else 1339 sk = kmalloc(prot->obj_size, priority); 1340 1341 if (sk != NULL) { 1342 kmemcheck_annotate_bitfield(sk, flags); 1343 1344 if (security_sk_alloc(sk, family, priority)) 1345 goto out_free; 1346 1347 if (!try_module_get(prot->owner)) 1348 goto out_free_sec; 1349 sk_tx_queue_clear(sk); 1350 } 1351 1352 return sk; 1353 1354 out_free_sec: 1355 security_sk_free(sk); 1356 out_free: 1357 if (slab != NULL) 1358 kmem_cache_free(slab, sk); 1359 else 1360 kfree(sk); 1361 return NULL; 1362 } 1363 1364 static void sk_prot_free(struct proto *prot, struct sock *sk) 1365 { 1366 struct kmem_cache *slab; 1367 struct module *owner; 1368 1369 owner = prot->owner; 1370 slab = prot->slab; 1371 1372 security_sk_free(sk); 1373 if (slab != NULL) 1374 kmem_cache_free(slab, sk); 1375 else 1376 kfree(sk); 1377 module_put(owner); 1378 } 1379 1380 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 1381 void sock_update_netprioidx(struct sock *sk) 1382 { 1383 if (in_interrupt()) 1384 return; 1385 1386 sk->sk_cgrp_prioidx = task_netprioidx(current); 1387 } 1388 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1389 #endif 1390 1391 /** 1392 * sk_alloc - All socket objects are allocated here 1393 * @net: the applicable net namespace 1394 * @family: protocol family 1395 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1396 * @prot: struct proto associated with this new sock instance 1397 * @kern: is this to be a kernel socket? 1398 */ 1399 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1400 struct proto *prot, int kern) 1401 { 1402 struct sock *sk; 1403 1404 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1405 if (sk) { 1406 sk->sk_family = family; 1407 /* 1408 * See comment in struct sock definition to understand 1409 * why we need sk_prot_creator -acme 1410 */ 1411 sk->sk_prot = sk->sk_prot_creator = prot; 1412 sock_lock_init(sk); 1413 sk->sk_net_refcnt = kern ? 0 : 1; 1414 if (likely(sk->sk_net_refcnt)) 1415 get_net(net); 1416 sock_net_set(sk, net); 1417 atomic_set(&sk->sk_wmem_alloc, 1); 1418 1419 sock_update_classid(sk); 1420 sock_update_netprioidx(sk); 1421 } 1422 1423 return sk; 1424 } 1425 EXPORT_SYMBOL(sk_alloc); 1426 1427 void sk_destruct(struct sock *sk) 1428 { 1429 struct sk_filter *filter; 1430 1431 if (sk->sk_destruct) 1432 sk->sk_destruct(sk); 1433 1434 filter = rcu_dereference_check(sk->sk_filter, 1435 atomic_read(&sk->sk_wmem_alloc) == 0); 1436 if (filter) { 1437 sk_filter_uncharge(sk, filter); 1438 RCU_INIT_POINTER(sk->sk_filter, NULL); 1439 } 1440 1441 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1442 1443 if (atomic_read(&sk->sk_omem_alloc)) 1444 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1445 __func__, atomic_read(&sk->sk_omem_alloc)); 1446 1447 if (sk->sk_peer_cred) 1448 put_cred(sk->sk_peer_cred); 1449 put_pid(sk->sk_peer_pid); 1450 if (likely(sk->sk_net_refcnt)) 1451 put_net(sock_net(sk)); 1452 sk_prot_free(sk->sk_prot_creator, sk); 1453 } 1454 1455 static void __sk_free(struct sock *sk) 1456 { 1457 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt)) 1458 sock_diag_broadcast_destroy(sk); 1459 else 1460 sk_destruct(sk); 1461 } 1462 1463 void sk_free(struct sock *sk) 1464 { 1465 /* 1466 * We subtract one from sk_wmem_alloc and can know if 1467 * some packets are still in some tx queue. 1468 * If not null, sock_wfree() will call __sk_free(sk) later 1469 */ 1470 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1471 __sk_free(sk); 1472 } 1473 EXPORT_SYMBOL(sk_free); 1474 1475 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1476 { 1477 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1478 sock_update_memcg(newsk); 1479 } 1480 1481 /** 1482 * sk_clone_lock - clone a socket, and lock its clone 1483 * @sk: the socket to clone 1484 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1485 * 1486 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1487 */ 1488 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1489 { 1490 struct sock *newsk; 1491 bool is_charged = true; 1492 1493 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1494 if (newsk != NULL) { 1495 struct sk_filter *filter; 1496 1497 sock_copy(newsk, sk); 1498 1499 /* SANITY */ 1500 get_net(sock_net(newsk)); 1501 sk_node_init(&newsk->sk_node); 1502 sock_lock_init(newsk); 1503 bh_lock_sock(newsk); 1504 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1505 newsk->sk_backlog.len = 0; 1506 1507 atomic_set(&newsk->sk_rmem_alloc, 0); 1508 /* 1509 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1510 */ 1511 atomic_set(&newsk->sk_wmem_alloc, 1); 1512 atomic_set(&newsk->sk_omem_alloc, 0); 1513 skb_queue_head_init(&newsk->sk_receive_queue); 1514 skb_queue_head_init(&newsk->sk_write_queue); 1515 1516 spin_lock_init(&newsk->sk_dst_lock); 1517 rwlock_init(&newsk->sk_callback_lock); 1518 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1519 af_callback_keys + newsk->sk_family, 1520 af_family_clock_key_strings[newsk->sk_family]); 1521 1522 newsk->sk_dst_cache = NULL; 1523 newsk->sk_wmem_queued = 0; 1524 newsk->sk_forward_alloc = 0; 1525 newsk->sk_send_head = NULL; 1526 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1527 1528 sock_reset_flag(newsk, SOCK_DONE); 1529 skb_queue_head_init(&newsk->sk_error_queue); 1530 1531 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1532 if (filter != NULL) 1533 /* though it's an empty new sock, the charging may fail 1534 * if sysctl_optmem_max was changed between creation of 1535 * original socket and cloning 1536 */ 1537 is_charged = sk_filter_charge(newsk, filter); 1538 1539 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) { 1540 /* It is still raw copy of parent, so invalidate 1541 * destructor and make plain sk_free() */ 1542 newsk->sk_destruct = NULL; 1543 bh_unlock_sock(newsk); 1544 sk_free(newsk); 1545 newsk = NULL; 1546 goto out; 1547 } 1548 1549 newsk->sk_err = 0; 1550 newsk->sk_priority = 0; 1551 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1552 atomic64_set(&newsk->sk_cookie, 0); 1553 /* 1554 * Before updating sk_refcnt, we must commit prior changes to memory 1555 * (Documentation/RCU/rculist_nulls.txt for details) 1556 */ 1557 smp_wmb(); 1558 atomic_set(&newsk->sk_refcnt, 2); 1559 1560 /* 1561 * Increment the counter in the same struct proto as the master 1562 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1563 * is the same as sk->sk_prot->socks, as this field was copied 1564 * with memcpy). 1565 * 1566 * This _changes_ the previous behaviour, where 1567 * tcp_create_openreq_child always was incrementing the 1568 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1569 * to be taken into account in all callers. -acme 1570 */ 1571 sk_refcnt_debug_inc(newsk); 1572 sk_set_socket(newsk, NULL); 1573 newsk->sk_wq = NULL; 1574 1575 sk_update_clone(sk, newsk); 1576 1577 if (newsk->sk_prot->sockets_allocated) 1578 sk_sockets_allocated_inc(newsk); 1579 1580 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1581 net_enable_timestamp(); 1582 } 1583 out: 1584 return newsk; 1585 } 1586 EXPORT_SYMBOL_GPL(sk_clone_lock); 1587 1588 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1589 { 1590 u32 max_segs = 1; 1591 1592 __sk_dst_set(sk, dst); 1593 sk->sk_route_caps = dst->dev->features; 1594 if (sk->sk_route_caps & NETIF_F_GSO) 1595 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1596 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1597 if (sk_can_gso(sk)) { 1598 if (dst->header_len) { 1599 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1600 } else { 1601 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1602 sk->sk_gso_max_size = dst->dev->gso_max_size; 1603 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 1604 } 1605 } 1606 sk->sk_gso_max_segs = max_segs; 1607 } 1608 EXPORT_SYMBOL_GPL(sk_setup_caps); 1609 1610 /* 1611 * Simple resource managers for sockets. 1612 */ 1613 1614 1615 /* 1616 * Write buffer destructor automatically called from kfree_skb. 1617 */ 1618 void sock_wfree(struct sk_buff *skb) 1619 { 1620 struct sock *sk = skb->sk; 1621 unsigned int len = skb->truesize; 1622 1623 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1624 /* 1625 * Keep a reference on sk_wmem_alloc, this will be released 1626 * after sk_write_space() call 1627 */ 1628 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1629 sk->sk_write_space(sk); 1630 len = 1; 1631 } 1632 /* 1633 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1634 * could not do because of in-flight packets 1635 */ 1636 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1637 __sk_free(sk); 1638 } 1639 EXPORT_SYMBOL(sock_wfree); 1640 1641 void skb_orphan_partial(struct sk_buff *skb) 1642 { 1643 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1644 * so we do not completely orphan skb, but transfert all 1645 * accounted bytes but one, to avoid unexpected reorders. 1646 */ 1647 if (skb->destructor == sock_wfree 1648 #ifdef CONFIG_INET 1649 || skb->destructor == tcp_wfree 1650 #endif 1651 ) { 1652 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1653 skb->truesize = 1; 1654 } else { 1655 skb_orphan(skb); 1656 } 1657 } 1658 EXPORT_SYMBOL(skb_orphan_partial); 1659 1660 /* 1661 * Read buffer destructor automatically called from kfree_skb. 1662 */ 1663 void sock_rfree(struct sk_buff *skb) 1664 { 1665 struct sock *sk = skb->sk; 1666 unsigned int len = skb->truesize; 1667 1668 atomic_sub(len, &sk->sk_rmem_alloc); 1669 sk_mem_uncharge(sk, len); 1670 } 1671 EXPORT_SYMBOL(sock_rfree); 1672 1673 /* 1674 * Buffer destructor for skbs that are not used directly in read or write 1675 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 1676 */ 1677 void sock_efree(struct sk_buff *skb) 1678 { 1679 sock_put(skb->sk); 1680 } 1681 EXPORT_SYMBOL(sock_efree); 1682 1683 kuid_t sock_i_uid(struct sock *sk) 1684 { 1685 kuid_t uid; 1686 1687 read_lock_bh(&sk->sk_callback_lock); 1688 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1689 read_unlock_bh(&sk->sk_callback_lock); 1690 return uid; 1691 } 1692 EXPORT_SYMBOL(sock_i_uid); 1693 1694 unsigned long sock_i_ino(struct sock *sk) 1695 { 1696 unsigned long ino; 1697 1698 read_lock_bh(&sk->sk_callback_lock); 1699 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1700 read_unlock_bh(&sk->sk_callback_lock); 1701 return ino; 1702 } 1703 EXPORT_SYMBOL(sock_i_ino); 1704 1705 /* 1706 * Allocate a skb from the socket's send buffer. 1707 */ 1708 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1709 gfp_t priority) 1710 { 1711 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1712 struct sk_buff *skb = alloc_skb(size, priority); 1713 if (skb) { 1714 skb_set_owner_w(skb, sk); 1715 return skb; 1716 } 1717 } 1718 return NULL; 1719 } 1720 EXPORT_SYMBOL(sock_wmalloc); 1721 1722 /* 1723 * Allocate a memory block from the socket's option memory buffer. 1724 */ 1725 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1726 { 1727 if ((unsigned int)size <= sysctl_optmem_max && 1728 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1729 void *mem; 1730 /* First do the add, to avoid the race if kmalloc 1731 * might sleep. 1732 */ 1733 atomic_add(size, &sk->sk_omem_alloc); 1734 mem = kmalloc(size, priority); 1735 if (mem) 1736 return mem; 1737 atomic_sub(size, &sk->sk_omem_alloc); 1738 } 1739 return NULL; 1740 } 1741 EXPORT_SYMBOL(sock_kmalloc); 1742 1743 /* Free an option memory block. Note, we actually want the inline 1744 * here as this allows gcc to detect the nullify and fold away the 1745 * condition entirely. 1746 */ 1747 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 1748 const bool nullify) 1749 { 1750 if (WARN_ON_ONCE(!mem)) 1751 return; 1752 if (nullify) 1753 kzfree(mem); 1754 else 1755 kfree(mem); 1756 atomic_sub(size, &sk->sk_omem_alloc); 1757 } 1758 1759 void sock_kfree_s(struct sock *sk, void *mem, int size) 1760 { 1761 __sock_kfree_s(sk, mem, size, false); 1762 } 1763 EXPORT_SYMBOL(sock_kfree_s); 1764 1765 void sock_kzfree_s(struct sock *sk, void *mem, int size) 1766 { 1767 __sock_kfree_s(sk, mem, size, true); 1768 } 1769 EXPORT_SYMBOL(sock_kzfree_s); 1770 1771 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1772 I think, these locks should be removed for datagram sockets. 1773 */ 1774 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1775 { 1776 DEFINE_WAIT(wait); 1777 1778 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1779 for (;;) { 1780 if (!timeo) 1781 break; 1782 if (signal_pending(current)) 1783 break; 1784 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1785 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1786 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1787 break; 1788 if (sk->sk_shutdown & SEND_SHUTDOWN) 1789 break; 1790 if (sk->sk_err) 1791 break; 1792 timeo = schedule_timeout(timeo); 1793 } 1794 finish_wait(sk_sleep(sk), &wait); 1795 return timeo; 1796 } 1797 1798 1799 /* 1800 * Generic send/receive buffer handlers 1801 */ 1802 1803 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1804 unsigned long data_len, int noblock, 1805 int *errcode, int max_page_order) 1806 { 1807 struct sk_buff *skb; 1808 long timeo; 1809 int err; 1810 1811 timeo = sock_sndtimeo(sk, noblock); 1812 for (;;) { 1813 err = sock_error(sk); 1814 if (err != 0) 1815 goto failure; 1816 1817 err = -EPIPE; 1818 if (sk->sk_shutdown & SEND_SHUTDOWN) 1819 goto failure; 1820 1821 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 1822 break; 1823 1824 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1825 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1826 err = -EAGAIN; 1827 if (!timeo) 1828 goto failure; 1829 if (signal_pending(current)) 1830 goto interrupted; 1831 timeo = sock_wait_for_wmem(sk, timeo); 1832 } 1833 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 1834 errcode, sk->sk_allocation); 1835 if (skb) 1836 skb_set_owner_w(skb, sk); 1837 return skb; 1838 1839 interrupted: 1840 err = sock_intr_errno(timeo); 1841 failure: 1842 *errcode = err; 1843 return NULL; 1844 } 1845 EXPORT_SYMBOL(sock_alloc_send_pskb); 1846 1847 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1848 int noblock, int *errcode) 1849 { 1850 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1851 } 1852 EXPORT_SYMBOL(sock_alloc_send_skb); 1853 1854 /* On 32bit arches, an skb frag is limited to 2^15 */ 1855 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1856 1857 /** 1858 * skb_page_frag_refill - check that a page_frag contains enough room 1859 * @sz: minimum size of the fragment we want to get 1860 * @pfrag: pointer to page_frag 1861 * @gfp: priority for memory allocation 1862 * 1863 * Note: While this allocator tries to use high order pages, there is 1864 * no guarantee that allocations succeed. Therefore, @sz MUST be 1865 * less or equal than PAGE_SIZE. 1866 */ 1867 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 1868 { 1869 if (pfrag->page) { 1870 if (atomic_read(&pfrag->page->_count) == 1) { 1871 pfrag->offset = 0; 1872 return true; 1873 } 1874 if (pfrag->offset + sz <= pfrag->size) 1875 return true; 1876 put_page(pfrag->page); 1877 } 1878 1879 pfrag->offset = 0; 1880 if (SKB_FRAG_PAGE_ORDER) { 1881 pfrag->page = alloc_pages((gfp & ~__GFP_WAIT) | __GFP_COMP | 1882 __GFP_NOWARN | __GFP_NORETRY, 1883 SKB_FRAG_PAGE_ORDER); 1884 if (likely(pfrag->page)) { 1885 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 1886 return true; 1887 } 1888 } 1889 pfrag->page = alloc_page(gfp); 1890 if (likely(pfrag->page)) { 1891 pfrag->size = PAGE_SIZE; 1892 return true; 1893 } 1894 return false; 1895 } 1896 EXPORT_SYMBOL(skb_page_frag_refill); 1897 1898 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1899 { 1900 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1901 return true; 1902 1903 sk_enter_memory_pressure(sk); 1904 sk_stream_moderate_sndbuf(sk); 1905 return false; 1906 } 1907 EXPORT_SYMBOL(sk_page_frag_refill); 1908 1909 static void __lock_sock(struct sock *sk) 1910 __releases(&sk->sk_lock.slock) 1911 __acquires(&sk->sk_lock.slock) 1912 { 1913 DEFINE_WAIT(wait); 1914 1915 for (;;) { 1916 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1917 TASK_UNINTERRUPTIBLE); 1918 spin_unlock_bh(&sk->sk_lock.slock); 1919 schedule(); 1920 spin_lock_bh(&sk->sk_lock.slock); 1921 if (!sock_owned_by_user(sk)) 1922 break; 1923 } 1924 finish_wait(&sk->sk_lock.wq, &wait); 1925 } 1926 1927 static void __release_sock(struct sock *sk) 1928 __releases(&sk->sk_lock.slock) 1929 __acquires(&sk->sk_lock.slock) 1930 { 1931 struct sk_buff *skb = sk->sk_backlog.head; 1932 1933 do { 1934 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1935 bh_unlock_sock(sk); 1936 1937 do { 1938 struct sk_buff *next = skb->next; 1939 1940 prefetch(next); 1941 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1942 skb->next = NULL; 1943 sk_backlog_rcv(sk, skb); 1944 1945 /* 1946 * We are in process context here with softirqs 1947 * disabled, use cond_resched_softirq() to preempt. 1948 * This is safe to do because we've taken the backlog 1949 * queue private: 1950 */ 1951 cond_resched_softirq(); 1952 1953 skb = next; 1954 } while (skb != NULL); 1955 1956 bh_lock_sock(sk); 1957 } while ((skb = sk->sk_backlog.head) != NULL); 1958 1959 /* 1960 * Doing the zeroing here guarantee we can not loop forever 1961 * while a wild producer attempts to flood us. 1962 */ 1963 sk->sk_backlog.len = 0; 1964 } 1965 1966 /** 1967 * sk_wait_data - wait for data to arrive at sk_receive_queue 1968 * @sk: sock to wait on 1969 * @timeo: for how long 1970 * 1971 * Now socket state including sk->sk_err is changed only under lock, 1972 * hence we may omit checks after joining wait queue. 1973 * We check receive queue before schedule() only as optimization; 1974 * it is very likely that release_sock() added new data. 1975 */ 1976 int sk_wait_data(struct sock *sk, long *timeo) 1977 { 1978 int rc; 1979 DEFINE_WAIT(wait); 1980 1981 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1982 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1983 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1984 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1985 finish_wait(sk_sleep(sk), &wait); 1986 return rc; 1987 } 1988 EXPORT_SYMBOL(sk_wait_data); 1989 1990 /** 1991 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1992 * @sk: socket 1993 * @size: memory size to allocate 1994 * @kind: allocation type 1995 * 1996 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1997 * rmem allocation. This function assumes that protocols which have 1998 * memory_pressure use sk_wmem_queued as write buffer accounting. 1999 */ 2000 int __sk_mem_schedule(struct sock *sk, int size, int kind) 2001 { 2002 struct proto *prot = sk->sk_prot; 2003 int amt = sk_mem_pages(size); 2004 long allocated; 2005 int parent_status = UNDER_LIMIT; 2006 2007 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 2008 2009 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 2010 2011 /* Under limit. */ 2012 if (parent_status == UNDER_LIMIT && 2013 allocated <= sk_prot_mem_limits(sk, 0)) { 2014 sk_leave_memory_pressure(sk); 2015 return 1; 2016 } 2017 2018 /* Under pressure. (we or our parents) */ 2019 if ((parent_status > SOFT_LIMIT) || 2020 allocated > sk_prot_mem_limits(sk, 1)) 2021 sk_enter_memory_pressure(sk); 2022 2023 /* Over hard limit (we or our parents) */ 2024 if ((parent_status == OVER_LIMIT) || 2025 (allocated > sk_prot_mem_limits(sk, 2))) 2026 goto suppress_allocation; 2027 2028 /* guarantee minimum buffer size under pressure */ 2029 if (kind == SK_MEM_RECV) { 2030 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2031 return 1; 2032 2033 } else { /* SK_MEM_SEND */ 2034 if (sk->sk_type == SOCK_STREAM) { 2035 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2036 return 1; 2037 } else if (atomic_read(&sk->sk_wmem_alloc) < 2038 prot->sysctl_wmem[0]) 2039 return 1; 2040 } 2041 2042 if (sk_has_memory_pressure(sk)) { 2043 int alloc; 2044 2045 if (!sk_under_memory_pressure(sk)) 2046 return 1; 2047 alloc = sk_sockets_allocated_read_positive(sk); 2048 if (sk_prot_mem_limits(sk, 2) > alloc * 2049 sk_mem_pages(sk->sk_wmem_queued + 2050 atomic_read(&sk->sk_rmem_alloc) + 2051 sk->sk_forward_alloc)) 2052 return 1; 2053 } 2054 2055 suppress_allocation: 2056 2057 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2058 sk_stream_moderate_sndbuf(sk); 2059 2060 /* Fail only if socket is _under_ its sndbuf. 2061 * In this case we cannot block, so that we have to fail. 2062 */ 2063 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2064 return 1; 2065 } 2066 2067 trace_sock_exceed_buf_limit(sk, prot, allocated); 2068 2069 /* Alas. Undo changes. */ 2070 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2071 2072 sk_memory_allocated_sub(sk, amt); 2073 2074 return 0; 2075 } 2076 EXPORT_SYMBOL(__sk_mem_schedule); 2077 2078 /** 2079 * __sk_reclaim - reclaim memory_allocated 2080 * @sk: socket 2081 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2082 */ 2083 void __sk_mem_reclaim(struct sock *sk, int amount) 2084 { 2085 amount >>= SK_MEM_QUANTUM_SHIFT; 2086 sk_memory_allocated_sub(sk, amount); 2087 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2088 2089 if (sk_under_memory_pressure(sk) && 2090 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2091 sk_leave_memory_pressure(sk); 2092 } 2093 EXPORT_SYMBOL(__sk_mem_reclaim); 2094 2095 2096 /* 2097 * Set of default routines for initialising struct proto_ops when 2098 * the protocol does not support a particular function. In certain 2099 * cases where it makes no sense for a protocol to have a "do nothing" 2100 * function, some default processing is provided. 2101 */ 2102 2103 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2104 { 2105 return -EOPNOTSUPP; 2106 } 2107 EXPORT_SYMBOL(sock_no_bind); 2108 2109 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2110 int len, int flags) 2111 { 2112 return -EOPNOTSUPP; 2113 } 2114 EXPORT_SYMBOL(sock_no_connect); 2115 2116 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2117 { 2118 return -EOPNOTSUPP; 2119 } 2120 EXPORT_SYMBOL(sock_no_socketpair); 2121 2122 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2123 { 2124 return -EOPNOTSUPP; 2125 } 2126 EXPORT_SYMBOL(sock_no_accept); 2127 2128 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2129 int *len, int peer) 2130 { 2131 return -EOPNOTSUPP; 2132 } 2133 EXPORT_SYMBOL(sock_no_getname); 2134 2135 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2136 { 2137 return 0; 2138 } 2139 EXPORT_SYMBOL(sock_no_poll); 2140 2141 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2142 { 2143 return -EOPNOTSUPP; 2144 } 2145 EXPORT_SYMBOL(sock_no_ioctl); 2146 2147 int sock_no_listen(struct socket *sock, int backlog) 2148 { 2149 return -EOPNOTSUPP; 2150 } 2151 EXPORT_SYMBOL(sock_no_listen); 2152 2153 int sock_no_shutdown(struct socket *sock, int how) 2154 { 2155 return -EOPNOTSUPP; 2156 } 2157 EXPORT_SYMBOL(sock_no_shutdown); 2158 2159 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2160 char __user *optval, unsigned int optlen) 2161 { 2162 return -EOPNOTSUPP; 2163 } 2164 EXPORT_SYMBOL(sock_no_setsockopt); 2165 2166 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2167 char __user *optval, int __user *optlen) 2168 { 2169 return -EOPNOTSUPP; 2170 } 2171 EXPORT_SYMBOL(sock_no_getsockopt); 2172 2173 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2174 { 2175 return -EOPNOTSUPP; 2176 } 2177 EXPORT_SYMBOL(sock_no_sendmsg); 2178 2179 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2180 int flags) 2181 { 2182 return -EOPNOTSUPP; 2183 } 2184 EXPORT_SYMBOL(sock_no_recvmsg); 2185 2186 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2187 { 2188 /* Mirror missing mmap method error code */ 2189 return -ENODEV; 2190 } 2191 EXPORT_SYMBOL(sock_no_mmap); 2192 2193 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2194 { 2195 ssize_t res; 2196 struct msghdr msg = {.msg_flags = flags}; 2197 struct kvec iov; 2198 char *kaddr = kmap(page); 2199 iov.iov_base = kaddr + offset; 2200 iov.iov_len = size; 2201 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2202 kunmap(page); 2203 return res; 2204 } 2205 EXPORT_SYMBOL(sock_no_sendpage); 2206 2207 /* 2208 * Default Socket Callbacks 2209 */ 2210 2211 static void sock_def_wakeup(struct sock *sk) 2212 { 2213 struct socket_wq *wq; 2214 2215 rcu_read_lock(); 2216 wq = rcu_dereference(sk->sk_wq); 2217 if (wq_has_sleeper(wq)) 2218 wake_up_interruptible_all(&wq->wait); 2219 rcu_read_unlock(); 2220 } 2221 2222 static void sock_def_error_report(struct sock *sk) 2223 { 2224 struct socket_wq *wq; 2225 2226 rcu_read_lock(); 2227 wq = rcu_dereference(sk->sk_wq); 2228 if (wq_has_sleeper(wq)) 2229 wake_up_interruptible_poll(&wq->wait, POLLERR); 2230 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2231 rcu_read_unlock(); 2232 } 2233 2234 static void sock_def_readable(struct sock *sk) 2235 { 2236 struct socket_wq *wq; 2237 2238 rcu_read_lock(); 2239 wq = rcu_dereference(sk->sk_wq); 2240 if (wq_has_sleeper(wq)) 2241 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2242 POLLRDNORM | POLLRDBAND); 2243 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2244 rcu_read_unlock(); 2245 } 2246 2247 static void sock_def_write_space(struct sock *sk) 2248 { 2249 struct socket_wq *wq; 2250 2251 rcu_read_lock(); 2252 2253 /* Do not wake up a writer until he can make "significant" 2254 * progress. --DaveM 2255 */ 2256 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2257 wq = rcu_dereference(sk->sk_wq); 2258 if (wq_has_sleeper(wq)) 2259 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2260 POLLWRNORM | POLLWRBAND); 2261 2262 /* Should agree with poll, otherwise some programs break */ 2263 if (sock_writeable(sk)) 2264 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2265 } 2266 2267 rcu_read_unlock(); 2268 } 2269 2270 static void sock_def_destruct(struct sock *sk) 2271 { 2272 } 2273 2274 void sk_send_sigurg(struct sock *sk) 2275 { 2276 if (sk->sk_socket && sk->sk_socket->file) 2277 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2278 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2279 } 2280 EXPORT_SYMBOL(sk_send_sigurg); 2281 2282 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2283 unsigned long expires) 2284 { 2285 if (!mod_timer(timer, expires)) 2286 sock_hold(sk); 2287 } 2288 EXPORT_SYMBOL(sk_reset_timer); 2289 2290 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2291 { 2292 if (del_timer(timer)) 2293 __sock_put(sk); 2294 } 2295 EXPORT_SYMBOL(sk_stop_timer); 2296 2297 void sock_init_data(struct socket *sock, struct sock *sk) 2298 { 2299 skb_queue_head_init(&sk->sk_receive_queue); 2300 skb_queue_head_init(&sk->sk_write_queue); 2301 skb_queue_head_init(&sk->sk_error_queue); 2302 2303 sk->sk_send_head = NULL; 2304 2305 init_timer(&sk->sk_timer); 2306 2307 sk->sk_allocation = GFP_KERNEL; 2308 sk->sk_rcvbuf = sysctl_rmem_default; 2309 sk->sk_sndbuf = sysctl_wmem_default; 2310 sk->sk_state = TCP_CLOSE; 2311 sk_set_socket(sk, sock); 2312 2313 sock_set_flag(sk, SOCK_ZAPPED); 2314 2315 if (sock) { 2316 sk->sk_type = sock->type; 2317 sk->sk_wq = sock->wq; 2318 sock->sk = sk; 2319 } else 2320 sk->sk_wq = NULL; 2321 2322 spin_lock_init(&sk->sk_dst_lock); 2323 rwlock_init(&sk->sk_callback_lock); 2324 lockdep_set_class_and_name(&sk->sk_callback_lock, 2325 af_callback_keys + sk->sk_family, 2326 af_family_clock_key_strings[sk->sk_family]); 2327 2328 sk->sk_state_change = sock_def_wakeup; 2329 sk->sk_data_ready = sock_def_readable; 2330 sk->sk_write_space = sock_def_write_space; 2331 sk->sk_error_report = sock_def_error_report; 2332 sk->sk_destruct = sock_def_destruct; 2333 2334 sk->sk_frag.page = NULL; 2335 sk->sk_frag.offset = 0; 2336 sk->sk_peek_off = -1; 2337 2338 sk->sk_peer_pid = NULL; 2339 sk->sk_peer_cred = NULL; 2340 sk->sk_write_pending = 0; 2341 sk->sk_rcvlowat = 1; 2342 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2343 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2344 2345 sk->sk_stamp = ktime_set(-1L, 0); 2346 2347 #ifdef CONFIG_NET_RX_BUSY_POLL 2348 sk->sk_napi_id = 0; 2349 sk->sk_ll_usec = sysctl_net_busy_read; 2350 #endif 2351 2352 sk->sk_max_pacing_rate = ~0U; 2353 sk->sk_pacing_rate = ~0U; 2354 /* 2355 * Before updating sk_refcnt, we must commit prior changes to memory 2356 * (Documentation/RCU/rculist_nulls.txt for details) 2357 */ 2358 smp_wmb(); 2359 atomic_set(&sk->sk_refcnt, 1); 2360 atomic_set(&sk->sk_drops, 0); 2361 } 2362 EXPORT_SYMBOL(sock_init_data); 2363 2364 void lock_sock_nested(struct sock *sk, int subclass) 2365 { 2366 might_sleep(); 2367 spin_lock_bh(&sk->sk_lock.slock); 2368 if (sk->sk_lock.owned) 2369 __lock_sock(sk); 2370 sk->sk_lock.owned = 1; 2371 spin_unlock(&sk->sk_lock.slock); 2372 /* 2373 * The sk_lock has mutex_lock() semantics here: 2374 */ 2375 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2376 local_bh_enable(); 2377 } 2378 EXPORT_SYMBOL(lock_sock_nested); 2379 2380 void release_sock(struct sock *sk) 2381 { 2382 /* 2383 * The sk_lock has mutex_unlock() semantics: 2384 */ 2385 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2386 2387 spin_lock_bh(&sk->sk_lock.slock); 2388 if (sk->sk_backlog.tail) 2389 __release_sock(sk); 2390 2391 /* Warning : release_cb() might need to release sk ownership, 2392 * ie call sock_release_ownership(sk) before us. 2393 */ 2394 if (sk->sk_prot->release_cb) 2395 sk->sk_prot->release_cb(sk); 2396 2397 sock_release_ownership(sk); 2398 if (waitqueue_active(&sk->sk_lock.wq)) 2399 wake_up(&sk->sk_lock.wq); 2400 spin_unlock_bh(&sk->sk_lock.slock); 2401 } 2402 EXPORT_SYMBOL(release_sock); 2403 2404 /** 2405 * lock_sock_fast - fast version of lock_sock 2406 * @sk: socket 2407 * 2408 * This version should be used for very small section, where process wont block 2409 * return false if fast path is taken 2410 * sk_lock.slock locked, owned = 0, BH disabled 2411 * return true if slow path is taken 2412 * sk_lock.slock unlocked, owned = 1, BH enabled 2413 */ 2414 bool lock_sock_fast(struct sock *sk) 2415 { 2416 might_sleep(); 2417 spin_lock_bh(&sk->sk_lock.slock); 2418 2419 if (!sk->sk_lock.owned) 2420 /* 2421 * Note : We must disable BH 2422 */ 2423 return false; 2424 2425 __lock_sock(sk); 2426 sk->sk_lock.owned = 1; 2427 spin_unlock(&sk->sk_lock.slock); 2428 /* 2429 * The sk_lock has mutex_lock() semantics here: 2430 */ 2431 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2432 local_bh_enable(); 2433 return true; 2434 } 2435 EXPORT_SYMBOL(lock_sock_fast); 2436 2437 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2438 { 2439 struct timeval tv; 2440 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2441 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2442 tv = ktime_to_timeval(sk->sk_stamp); 2443 if (tv.tv_sec == -1) 2444 return -ENOENT; 2445 if (tv.tv_sec == 0) { 2446 sk->sk_stamp = ktime_get_real(); 2447 tv = ktime_to_timeval(sk->sk_stamp); 2448 } 2449 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2450 } 2451 EXPORT_SYMBOL(sock_get_timestamp); 2452 2453 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2454 { 2455 struct timespec ts; 2456 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2457 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2458 ts = ktime_to_timespec(sk->sk_stamp); 2459 if (ts.tv_sec == -1) 2460 return -ENOENT; 2461 if (ts.tv_sec == 0) { 2462 sk->sk_stamp = ktime_get_real(); 2463 ts = ktime_to_timespec(sk->sk_stamp); 2464 } 2465 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2466 } 2467 EXPORT_SYMBOL(sock_get_timestampns); 2468 2469 void sock_enable_timestamp(struct sock *sk, int flag) 2470 { 2471 if (!sock_flag(sk, flag)) { 2472 unsigned long previous_flags = sk->sk_flags; 2473 2474 sock_set_flag(sk, flag); 2475 /* 2476 * we just set one of the two flags which require net 2477 * time stamping, but time stamping might have been on 2478 * already because of the other one 2479 */ 2480 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2481 net_enable_timestamp(); 2482 } 2483 } 2484 2485 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2486 int level, int type) 2487 { 2488 struct sock_exterr_skb *serr; 2489 struct sk_buff *skb; 2490 int copied, err; 2491 2492 err = -EAGAIN; 2493 skb = sock_dequeue_err_skb(sk); 2494 if (skb == NULL) 2495 goto out; 2496 2497 copied = skb->len; 2498 if (copied > len) { 2499 msg->msg_flags |= MSG_TRUNC; 2500 copied = len; 2501 } 2502 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2503 if (err) 2504 goto out_free_skb; 2505 2506 sock_recv_timestamp(msg, sk, skb); 2507 2508 serr = SKB_EXT_ERR(skb); 2509 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2510 2511 msg->msg_flags |= MSG_ERRQUEUE; 2512 err = copied; 2513 2514 out_free_skb: 2515 kfree_skb(skb); 2516 out: 2517 return err; 2518 } 2519 EXPORT_SYMBOL(sock_recv_errqueue); 2520 2521 /* 2522 * Get a socket option on an socket. 2523 * 2524 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2525 * asynchronous errors should be reported by getsockopt. We assume 2526 * this means if you specify SO_ERROR (otherwise whats the point of it). 2527 */ 2528 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2529 char __user *optval, int __user *optlen) 2530 { 2531 struct sock *sk = sock->sk; 2532 2533 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2534 } 2535 EXPORT_SYMBOL(sock_common_getsockopt); 2536 2537 #ifdef CONFIG_COMPAT 2538 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2539 char __user *optval, int __user *optlen) 2540 { 2541 struct sock *sk = sock->sk; 2542 2543 if (sk->sk_prot->compat_getsockopt != NULL) 2544 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2545 optval, optlen); 2546 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2547 } 2548 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2549 #endif 2550 2551 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 2552 int flags) 2553 { 2554 struct sock *sk = sock->sk; 2555 int addr_len = 0; 2556 int err; 2557 2558 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 2559 flags & ~MSG_DONTWAIT, &addr_len); 2560 if (err >= 0) 2561 msg->msg_namelen = addr_len; 2562 return err; 2563 } 2564 EXPORT_SYMBOL(sock_common_recvmsg); 2565 2566 /* 2567 * Set socket options on an inet socket. 2568 */ 2569 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2570 char __user *optval, unsigned int optlen) 2571 { 2572 struct sock *sk = sock->sk; 2573 2574 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2575 } 2576 EXPORT_SYMBOL(sock_common_setsockopt); 2577 2578 #ifdef CONFIG_COMPAT 2579 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2580 char __user *optval, unsigned int optlen) 2581 { 2582 struct sock *sk = sock->sk; 2583 2584 if (sk->sk_prot->compat_setsockopt != NULL) 2585 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2586 optval, optlen); 2587 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2588 } 2589 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2590 #endif 2591 2592 void sk_common_release(struct sock *sk) 2593 { 2594 if (sk->sk_prot->destroy) 2595 sk->sk_prot->destroy(sk); 2596 2597 /* 2598 * Observation: when sock_common_release is called, processes have 2599 * no access to socket. But net still has. 2600 * Step one, detach it from networking: 2601 * 2602 * A. Remove from hash tables. 2603 */ 2604 2605 sk->sk_prot->unhash(sk); 2606 2607 /* 2608 * In this point socket cannot receive new packets, but it is possible 2609 * that some packets are in flight because some CPU runs receiver and 2610 * did hash table lookup before we unhashed socket. They will achieve 2611 * receive queue and will be purged by socket destructor. 2612 * 2613 * Also we still have packets pending on receive queue and probably, 2614 * our own packets waiting in device queues. sock_destroy will drain 2615 * receive queue, but transmitted packets will delay socket destruction 2616 * until the last reference will be released. 2617 */ 2618 2619 sock_orphan(sk); 2620 2621 xfrm_sk_free_policy(sk); 2622 2623 sk_refcnt_debug_release(sk); 2624 2625 if (sk->sk_frag.page) { 2626 put_page(sk->sk_frag.page); 2627 sk->sk_frag.page = NULL; 2628 } 2629 2630 sock_put(sk); 2631 } 2632 EXPORT_SYMBOL(sk_common_release); 2633 2634 #ifdef CONFIG_PROC_FS 2635 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2636 struct prot_inuse { 2637 int val[PROTO_INUSE_NR]; 2638 }; 2639 2640 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2641 2642 #ifdef CONFIG_NET_NS 2643 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2644 { 2645 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2646 } 2647 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2648 2649 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2650 { 2651 int cpu, idx = prot->inuse_idx; 2652 int res = 0; 2653 2654 for_each_possible_cpu(cpu) 2655 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2656 2657 return res >= 0 ? res : 0; 2658 } 2659 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2660 2661 static int __net_init sock_inuse_init_net(struct net *net) 2662 { 2663 net->core.inuse = alloc_percpu(struct prot_inuse); 2664 return net->core.inuse ? 0 : -ENOMEM; 2665 } 2666 2667 static void __net_exit sock_inuse_exit_net(struct net *net) 2668 { 2669 free_percpu(net->core.inuse); 2670 } 2671 2672 static struct pernet_operations net_inuse_ops = { 2673 .init = sock_inuse_init_net, 2674 .exit = sock_inuse_exit_net, 2675 }; 2676 2677 static __init int net_inuse_init(void) 2678 { 2679 if (register_pernet_subsys(&net_inuse_ops)) 2680 panic("Cannot initialize net inuse counters"); 2681 2682 return 0; 2683 } 2684 2685 core_initcall(net_inuse_init); 2686 #else 2687 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2688 2689 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2690 { 2691 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2692 } 2693 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2694 2695 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2696 { 2697 int cpu, idx = prot->inuse_idx; 2698 int res = 0; 2699 2700 for_each_possible_cpu(cpu) 2701 res += per_cpu(prot_inuse, cpu).val[idx]; 2702 2703 return res >= 0 ? res : 0; 2704 } 2705 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2706 #endif 2707 2708 static void assign_proto_idx(struct proto *prot) 2709 { 2710 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2711 2712 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2713 pr_err("PROTO_INUSE_NR exhausted\n"); 2714 return; 2715 } 2716 2717 set_bit(prot->inuse_idx, proto_inuse_idx); 2718 } 2719 2720 static void release_proto_idx(struct proto *prot) 2721 { 2722 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2723 clear_bit(prot->inuse_idx, proto_inuse_idx); 2724 } 2725 #else 2726 static inline void assign_proto_idx(struct proto *prot) 2727 { 2728 } 2729 2730 static inline void release_proto_idx(struct proto *prot) 2731 { 2732 } 2733 #endif 2734 2735 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 2736 { 2737 if (!rsk_prot) 2738 return; 2739 kfree(rsk_prot->slab_name); 2740 rsk_prot->slab_name = NULL; 2741 if (rsk_prot->slab) { 2742 kmem_cache_destroy(rsk_prot->slab); 2743 rsk_prot->slab = NULL; 2744 } 2745 } 2746 2747 static int req_prot_init(const struct proto *prot) 2748 { 2749 struct request_sock_ops *rsk_prot = prot->rsk_prot; 2750 2751 if (!rsk_prot) 2752 return 0; 2753 2754 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 2755 prot->name); 2756 if (!rsk_prot->slab_name) 2757 return -ENOMEM; 2758 2759 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 2760 rsk_prot->obj_size, 0, 2761 0, NULL); 2762 2763 if (!rsk_prot->slab) { 2764 pr_crit("%s: Can't create request sock SLAB cache!\n", 2765 prot->name); 2766 return -ENOMEM; 2767 } 2768 return 0; 2769 } 2770 2771 int proto_register(struct proto *prot, int alloc_slab) 2772 { 2773 if (alloc_slab) { 2774 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2775 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2776 NULL); 2777 2778 if (prot->slab == NULL) { 2779 pr_crit("%s: Can't create sock SLAB cache!\n", 2780 prot->name); 2781 goto out; 2782 } 2783 2784 if (req_prot_init(prot)) 2785 goto out_free_request_sock_slab; 2786 2787 if (prot->twsk_prot != NULL) { 2788 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2789 2790 if (prot->twsk_prot->twsk_slab_name == NULL) 2791 goto out_free_request_sock_slab; 2792 2793 prot->twsk_prot->twsk_slab = 2794 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2795 prot->twsk_prot->twsk_obj_size, 2796 0, 2797 prot->slab_flags, 2798 NULL); 2799 if (prot->twsk_prot->twsk_slab == NULL) 2800 goto out_free_timewait_sock_slab_name; 2801 } 2802 } 2803 2804 mutex_lock(&proto_list_mutex); 2805 list_add(&prot->node, &proto_list); 2806 assign_proto_idx(prot); 2807 mutex_unlock(&proto_list_mutex); 2808 return 0; 2809 2810 out_free_timewait_sock_slab_name: 2811 kfree(prot->twsk_prot->twsk_slab_name); 2812 out_free_request_sock_slab: 2813 req_prot_cleanup(prot->rsk_prot); 2814 2815 kmem_cache_destroy(prot->slab); 2816 prot->slab = NULL; 2817 out: 2818 return -ENOBUFS; 2819 } 2820 EXPORT_SYMBOL(proto_register); 2821 2822 void proto_unregister(struct proto *prot) 2823 { 2824 mutex_lock(&proto_list_mutex); 2825 release_proto_idx(prot); 2826 list_del(&prot->node); 2827 mutex_unlock(&proto_list_mutex); 2828 2829 if (prot->slab != NULL) { 2830 kmem_cache_destroy(prot->slab); 2831 prot->slab = NULL; 2832 } 2833 2834 req_prot_cleanup(prot->rsk_prot); 2835 2836 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2837 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2838 kfree(prot->twsk_prot->twsk_slab_name); 2839 prot->twsk_prot->twsk_slab = NULL; 2840 } 2841 } 2842 EXPORT_SYMBOL(proto_unregister); 2843 2844 #ifdef CONFIG_PROC_FS 2845 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2846 __acquires(proto_list_mutex) 2847 { 2848 mutex_lock(&proto_list_mutex); 2849 return seq_list_start_head(&proto_list, *pos); 2850 } 2851 2852 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2853 { 2854 return seq_list_next(v, &proto_list, pos); 2855 } 2856 2857 static void proto_seq_stop(struct seq_file *seq, void *v) 2858 __releases(proto_list_mutex) 2859 { 2860 mutex_unlock(&proto_list_mutex); 2861 } 2862 2863 static char proto_method_implemented(const void *method) 2864 { 2865 return method == NULL ? 'n' : 'y'; 2866 } 2867 static long sock_prot_memory_allocated(struct proto *proto) 2868 { 2869 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2870 } 2871 2872 static char *sock_prot_memory_pressure(struct proto *proto) 2873 { 2874 return proto->memory_pressure != NULL ? 2875 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2876 } 2877 2878 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2879 { 2880 2881 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2882 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2883 proto->name, 2884 proto->obj_size, 2885 sock_prot_inuse_get(seq_file_net(seq), proto), 2886 sock_prot_memory_allocated(proto), 2887 sock_prot_memory_pressure(proto), 2888 proto->max_header, 2889 proto->slab == NULL ? "no" : "yes", 2890 module_name(proto->owner), 2891 proto_method_implemented(proto->close), 2892 proto_method_implemented(proto->connect), 2893 proto_method_implemented(proto->disconnect), 2894 proto_method_implemented(proto->accept), 2895 proto_method_implemented(proto->ioctl), 2896 proto_method_implemented(proto->init), 2897 proto_method_implemented(proto->destroy), 2898 proto_method_implemented(proto->shutdown), 2899 proto_method_implemented(proto->setsockopt), 2900 proto_method_implemented(proto->getsockopt), 2901 proto_method_implemented(proto->sendmsg), 2902 proto_method_implemented(proto->recvmsg), 2903 proto_method_implemented(proto->sendpage), 2904 proto_method_implemented(proto->bind), 2905 proto_method_implemented(proto->backlog_rcv), 2906 proto_method_implemented(proto->hash), 2907 proto_method_implemented(proto->unhash), 2908 proto_method_implemented(proto->get_port), 2909 proto_method_implemented(proto->enter_memory_pressure)); 2910 } 2911 2912 static int proto_seq_show(struct seq_file *seq, void *v) 2913 { 2914 if (v == &proto_list) 2915 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2916 "protocol", 2917 "size", 2918 "sockets", 2919 "memory", 2920 "press", 2921 "maxhdr", 2922 "slab", 2923 "module", 2924 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2925 else 2926 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2927 return 0; 2928 } 2929 2930 static const struct seq_operations proto_seq_ops = { 2931 .start = proto_seq_start, 2932 .next = proto_seq_next, 2933 .stop = proto_seq_stop, 2934 .show = proto_seq_show, 2935 }; 2936 2937 static int proto_seq_open(struct inode *inode, struct file *file) 2938 { 2939 return seq_open_net(inode, file, &proto_seq_ops, 2940 sizeof(struct seq_net_private)); 2941 } 2942 2943 static const struct file_operations proto_seq_fops = { 2944 .owner = THIS_MODULE, 2945 .open = proto_seq_open, 2946 .read = seq_read, 2947 .llseek = seq_lseek, 2948 .release = seq_release_net, 2949 }; 2950 2951 static __net_init int proto_init_net(struct net *net) 2952 { 2953 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2954 return -ENOMEM; 2955 2956 return 0; 2957 } 2958 2959 static __net_exit void proto_exit_net(struct net *net) 2960 { 2961 remove_proc_entry("protocols", net->proc_net); 2962 } 2963 2964 2965 static __net_initdata struct pernet_operations proto_net_ops = { 2966 .init = proto_init_net, 2967 .exit = proto_exit_net, 2968 }; 2969 2970 static int __init proto_init(void) 2971 { 2972 return register_pernet_subsys(&proto_net_ops); 2973 } 2974 2975 subsys_initcall(proto_init); 2976 2977 #endif /* PROC_FS */ 2978