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> 134 135 #include <linux/filter.h> 136 137 #include <trace/events/sock.h> 138 139 #ifdef CONFIG_INET 140 #include <net/tcp.h> 141 #endif 142 143 #include <net/busy_poll.h> 144 145 static DEFINE_MUTEX(proto_list_mutex); 146 static LIST_HEAD(proto_list); 147 148 /** 149 * sk_ns_capable - General socket capability test 150 * @sk: Socket to use a capability on or through 151 * @user_ns: The user namespace of the capability to use 152 * @cap: The capability to use 153 * 154 * Test to see if the opener of the socket had when the socket was 155 * created and the current process has the capability @cap in the user 156 * namespace @user_ns. 157 */ 158 bool sk_ns_capable(const struct sock *sk, 159 struct user_namespace *user_ns, int cap) 160 { 161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 162 ns_capable(user_ns, cap); 163 } 164 EXPORT_SYMBOL(sk_ns_capable); 165 166 /** 167 * sk_capable - Socket global capability test 168 * @sk: Socket to use a capability on or through 169 * @cap: The global capability to use 170 * 171 * Test to see if the opener of the socket had when the socket was 172 * created and the current process has the capability @cap in all user 173 * namespaces. 174 */ 175 bool sk_capable(const struct sock *sk, int cap) 176 { 177 return sk_ns_capable(sk, &init_user_ns, cap); 178 } 179 EXPORT_SYMBOL(sk_capable); 180 181 /** 182 * sk_net_capable - Network namespace socket capability test 183 * @sk: Socket to use a capability on or through 184 * @cap: The capability to use 185 * 186 * Test to see if the opener of the socket had when the socket was created 187 * and the current process has the capability @cap over the network namespace 188 * the socket is a member of. 189 */ 190 bool sk_net_capable(const struct sock *sk, int cap) 191 { 192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 193 } 194 EXPORT_SYMBOL(sk_net_capable); 195 196 197 #ifdef CONFIG_MEMCG_KMEM 198 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 199 { 200 struct proto *proto; 201 int ret = 0; 202 203 mutex_lock(&proto_list_mutex); 204 list_for_each_entry(proto, &proto_list, node) { 205 if (proto->init_cgroup) { 206 ret = proto->init_cgroup(memcg, ss); 207 if (ret) 208 goto out; 209 } 210 } 211 212 mutex_unlock(&proto_list_mutex); 213 return ret; 214 out: 215 list_for_each_entry_continue_reverse(proto, &proto_list, node) 216 if (proto->destroy_cgroup) 217 proto->destroy_cgroup(memcg); 218 mutex_unlock(&proto_list_mutex); 219 return ret; 220 } 221 222 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 223 { 224 struct proto *proto; 225 226 mutex_lock(&proto_list_mutex); 227 list_for_each_entry_reverse(proto, &proto_list, node) 228 if (proto->destroy_cgroup) 229 proto->destroy_cgroup(memcg); 230 mutex_unlock(&proto_list_mutex); 231 } 232 #endif 233 234 /* 235 * Each address family might have different locking rules, so we have 236 * one slock key per address family: 237 */ 238 static struct lock_class_key af_family_keys[AF_MAX]; 239 static struct lock_class_key af_family_slock_keys[AF_MAX]; 240 241 #if defined(CONFIG_MEMCG_KMEM) 242 struct static_key memcg_socket_limit_enabled; 243 EXPORT_SYMBOL(memcg_socket_limit_enabled); 244 #endif 245 246 /* 247 * Make lock validator output more readable. (we pre-construct these 248 * strings build-time, so that runtime initialization of socket 249 * locks is fast): 250 */ 251 static const char *const af_family_key_strings[AF_MAX+1] = { 252 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 253 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 254 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 255 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 256 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 257 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 258 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 259 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 260 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 261 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 262 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 263 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 264 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 265 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX" 266 }; 267 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 268 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 269 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 270 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 271 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 272 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 273 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 274 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 275 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 276 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 277 "slock-27" , "slock-28" , "slock-AF_CAN" , 278 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 279 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 280 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 281 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX" 282 }; 283 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 284 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 285 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 286 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 287 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 288 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 289 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 290 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 291 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 292 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 293 "clock-27" , "clock-28" , "clock-AF_CAN" , 294 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 295 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 296 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 297 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX" 298 }; 299 300 /* 301 * sk_callback_lock locking rules are per-address-family, 302 * so split the lock classes by using a per-AF key: 303 */ 304 static struct lock_class_key af_callback_keys[AF_MAX]; 305 306 /* Take into consideration the size of the struct sk_buff overhead in the 307 * determination of these values, since that is non-constant across 308 * platforms. This makes socket queueing behavior and performance 309 * not depend upon such differences. 310 */ 311 #define _SK_MEM_PACKETS 256 312 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 313 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 314 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 315 316 /* Run time adjustable parameters. */ 317 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 318 EXPORT_SYMBOL(sysctl_wmem_max); 319 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 320 EXPORT_SYMBOL(sysctl_rmem_max); 321 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 322 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 323 324 /* Maximal space eaten by iovec or ancillary data plus some space */ 325 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 326 EXPORT_SYMBOL(sysctl_optmem_max); 327 328 int sysctl_tstamp_allow_data __read_mostly = 1; 329 330 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 331 EXPORT_SYMBOL_GPL(memalloc_socks); 332 333 /** 334 * sk_set_memalloc - sets %SOCK_MEMALLOC 335 * @sk: socket to set it on 336 * 337 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 338 * It's the responsibility of the admin to adjust min_free_kbytes 339 * to meet the requirements 340 */ 341 void sk_set_memalloc(struct sock *sk) 342 { 343 sock_set_flag(sk, SOCK_MEMALLOC); 344 sk->sk_allocation |= __GFP_MEMALLOC; 345 static_key_slow_inc(&memalloc_socks); 346 } 347 EXPORT_SYMBOL_GPL(sk_set_memalloc); 348 349 void sk_clear_memalloc(struct sock *sk) 350 { 351 sock_reset_flag(sk, SOCK_MEMALLOC); 352 sk->sk_allocation &= ~__GFP_MEMALLOC; 353 static_key_slow_dec(&memalloc_socks); 354 355 /* 356 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 357 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 358 * it has rmem allocations there is a risk that the user of the 359 * socket cannot make forward progress due to exceeding the rmem 360 * limits. By rights, sk_clear_memalloc() should only be called 361 * on sockets being torn down but warn and reset the accounting if 362 * that assumption breaks. 363 */ 364 if (WARN_ON(sk->sk_forward_alloc)) 365 sk_mem_reclaim(sk); 366 } 367 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 368 369 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 370 { 371 int ret; 372 unsigned long pflags = current->flags; 373 374 /* these should have been dropped before queueing */ 375 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 376 377 current->flags |= PF_MEMALLOC; 378 ret = sk->sk_backlog_rcv(sk, skb); 379 tsk_restore_flags(current, pflags, PF_MEMALLOC); 380 381 return ret; 382 } 383 EXPORT_SYMBOL(__sk_backlog_rcv); 384 385 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 386 { 387 struct timeval tv; 388 389 if (optlen < sizeof(tv)) 390 return -EINVAL; 391 if (copy_from_user(&tv, optval, sizeof(tv))) 392 return -EFAULT; 393 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 394 return -EDOM; 395 396 if (tv.tv_sec < 0) { 397 static int warned __read_mostly; 398 399 *timeo_p = 0; 400 if (warned < 10 && net_ratelimit()) { 401 warned++; 402 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 403 __func__, current->comm, task_pid_nr(current)); 404 } 405 return 0; 406 } 407 *timeo_p = MAX_SCHEDULE_TIMEOUT; 408 if (tv.tv_sec == 0 && tv.tv_usec == 0) 409 return 0; 410 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 411 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 412 return 0; 413 } 414 415 static void sock_warn_obsolete_bsdism(const char *name) 416 { 417 static int warned; 418 static char warncomm[TASK_COMM_LEN]; 419 if (strcmp(warncomm, current->comm) && warned < 5) { 420 strcpy(warncomm, current->comm); 421 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 422 warncomm, name); 423 warned++; 424 } 425 } 426 427 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 428 429 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 430 { 431 if (sk->sk_flags & flags) { 432 sk->sk_flags &= ~flags; 433 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 434 net_disable_timestamp(); 435 } 436 } 437 438 439 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 440 { 441 int err; 442 unsigned long flags; 443 struct sk_buff_head *list = &sk->sk_receive_queue; 444 445 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 446 atomic_inc(&sk->sk_drops); 447 trace_sock_rcvqueue_full(sk, skb); 448 return -ENOMEM; 449 } 450 451 err = sk_filter(sk, skb); 452 if (err) 453 return err; 454 455 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 456 atomic_inc(&sk->sk_drops); 457 return -ENOBUFS; 458 } 459 460 skb->dev = NULL; 461 skb_set_owner_r(skb, sk); 462 463 /* we escape from rcu protected region, make sure we dont leak 464 * a norefcounted dst 465 */ 466 skb_dst_force(skb); 467 468 spin_lock_irqsave(&list->lock, flags); 469 sock_skb_set_dropcount(sk, skb); 470 __skb_queue_tail(list, skb); 471 spin_unlock_irqrestore(&list->lock, flags); 472 473 if (!sock_flag(sk, SOCK_DEAD)) 474 sk->sk_data_ready(sk); 475 return 0; 476 } 477 EXPORT_SYMBOL(sock_queue_rcv_skb); 478 479 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 480 { 481 int rc = NET_RX_SUCCESS; 482 483 if (sk_filter(sk, skb)) 484 goto discard_and_relse; 485 486 skb->dev = NULL; 487 488 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 489 atomic_inc(&sk->sk_drops); 490 goto discard_and_relse; 491 } 492 if (nested) 493 bh_lock_sock_nested(sk); 494 else 495 bh_lock_sock(sk); 496 if (!sock_owned_by_user(sk)) { 497 /* 498 * trylock + unlock semantics: 499 */ 500 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 501 502 rc = sk_backlog_rcv(sk, skb); 503 504 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 505 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 506 bh_unlock_sock(sk); 507 atomic_inc(&sk->sk_drops); 508 goto discard_and_relse; 509 } 510 511 bh_unlock_sock(sk); 512 out: 513 sock_put(sk); 514 return rc; 515 discard_and_relse: 516 kfree_skb(skb); 517 goto out; 518 } 519 EXPORT_SYMBOL(sk_receive_skb); 520 521 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 522 { 523 struct dst_entry *dst = __sk_dst_get(sk); 524 525 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 526 sk_tx_queue_clear(sk); 527 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 528 dst_release(dst); 529 return NULL; 530 } 531 532 return dst; 533 } 534 EXPORT_SYMBOL(__sk_dst_check); 535 536 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 537 { 538 struct dst_entry *dst = sk_dst_get(sk); 539 540 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 541 sk_dst_reset(sk); 542 dst_release(dst); 543 return NULL; 544 } 545 546 return dst; 547 } 548 EXPORT_SYMBOL(sk_dst_check); 549 550 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 551 int optlen) 552 { 553 int ret = -ENOPROTOOPT; 554 #ifdef CONFIG_NETDEVICES 555 struct net *net = sock_net(sk); 556 char devname[IFNAMSIZ]; 557 int index; 558 559 /* Sorry... */ 560 ret = -EPERM; 561 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 562 goto out; 563 564 ret = -EINVAL; 565 if (optlen < 0) 566 goto out; 567 568 /* Bind this socket to a particular device like "eth0", 569 * as specified in the passed interface name. If the 570 * name is "" or the option length is zero the socket 571 * is not bound. 572 */ 573 if (optlen > IFNAMSIZ - 1) 574 optlen = IFNAMSIZ - 1; 575 memset(devname, 0, sizeof(devname)); 576 577 ret = -EFAULT; 578 if (copy_from_user(devname, optval, optlen)) 579 goto out; 580 581 index = 0; 582 if (devname[0] != '\0') { 583 struct net_device *dev; 584 585 rcu_read_lock(); 586 dev = dev_get_by_name_rcu(net, devname); 587 if (dev) 588 index = dev->ifindex; 589 rcu_read_unlock(); 590 ret = -ENODEV; 591 if (!dev) 592 goto out; 593 } 594 595 lock_sock(sk); 596 sk->sk_bound_dev_if = index; 597 sk_dst_reset(sk); 598 release_sock(sk); 599 600 ret = 0; 601 602 out: 603 #endif 604 605 return ret; 606 } 607 608 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 609 int __user *optlen, int len) 610 { 611 int ret = -ENOPROTOOPT; 612 #ifdef CONFIG_NETDEVICES 613 struct net *net = sock_net(sk); 614 char devname[IFNAMSIZ]; 615 616 if (sk->sk_bound_dev_if == 0) { 617 len = 0; 618 goto zero; 619 } 620 621 ret = -EINVAL; 622 if (len < IFNAMSIZ) 623 goto out; 624 625 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 626 if (ret) 627 goto out; 628 629 len = strlen(devname) + 1; 630 631 ret = -EFAULT; 632 if (copy_to_user(optval, devname, len)) 633 goto out; 634 635 zero: 636 ret = -EFAULT; 637 if (put_user(len, optlen)) 638 goto out; 639 640 ret = 0; 641 642 out: 643 #endif 644 645 return ret; 646 } 647 648 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 649 { 650 if (valbool) 651 sock_set_flag(sk, bit); 652 else 653 sock_reset_flag(sk, bit); 654 } 655 656 /* 657 * This is meant for all protocols to use and covers goings on 658 * at the socket level. Everything here is generic. 659 */ 660 661 int sock_setsockopt(struct socket *sock, int level, int optname, 662 char __user *optval, unsigned int optlen) 663 { 664 struct sock *sk = sock->sk; 665 int val; 666 int valbool; 667 struct linger ling; 668 int ret = 0; 669 670 /* 671 * Options without arguments 672 */ 673 674 if (optname == SO_BINDTODEVICE) 675 return sock_setbindtodevice(sk, optval, optlen); 676 677 if (optlen < sizeof(int)) 678 return -EINVAL; 679 680 if (get_user(val, (int __user *)optval)) 681 return -EFAULT; 682 683 valbool = val ? 1 : 0; 684 685 lock_sock(sk); 686 687 switch (optname) { 688 case SO_DEBUG: 689 if (val && !capable(CAP_NET_ADMIN)) 690 ret = -EACCES; 691 else 692 sock_valbool_flag(sk, SOCK_DBG, valbool); 693 break; 694 case SO_REUSEADDR: 695 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 696 break; 697 case SO_REUSEPORT: 698 sk->sk_reuseport = valbool; 699 break; 700 case SO_TYPE: 701 case SO_PROTOCOL: 702 case SO_DOMAIN: 703 case SO_ERROR: 704 ret = -ENOPROTOOPT; 705 break; 706 case SO_DONTROUTE: 707 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 708 break; 709 case SO_BROADCAST: 710 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 711 break; 712 case SO_SNDBUF: 713 /* Don't error on this BSD doesn't and if you think 714 * about it this is right. Otherwise apps have to 715 * play 'guess the biggest size' games. RCVBUF/SNDBUF 716 * are treated in BSD as hints 717 */ 718 val = min_t(u32, val, sysctl_wmem_max); 719 set_sndbuf: 720 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 721 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 722 /* Wake up sending tasks if we upped the value. */ 723 sk->sk_write_space(sk); 724 break; 725 726 case SO_SNDBUFFORCE: 727 if (!capable(CAP_NET_ADMIN)) { 728 ret = -EPERM; 729 break; 730 } 731 goto set_sndbuf; 732 733 case SO_RCVBUF: 734 /* Don't error on this BSD doesn't and if you think 735 * about it this is right. Otherwise apps have to 736 * play 'guess the biggest size' games. RCVBUF/SNDBUF 737 * are treated in BSD as hints 738 */ 739 val = min_t(u32, val, sysctl_rmem_max); 740 set_rcvbuf: 741 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 742 /* 743 * We double it on the way in to account for 744 * "struct sk_buff" etc. overhead. Applications 745 * assume that the SO_RCVBUF setting they make will 746 * allow that much actual data to be received on that 747 * socket. 748 * 749 * Applications are unaware that "struct sk_buff" and 750 * other overheads allocate from the receive buffer 751 * during socket buffer allocation. 752 * 753 * And after considering the possible alternatives, 754 * returning the value we actually used in getsockopt 755 * is the most desirable behavior. 756 */ 757 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 758 break; 759 760 case SO_RCVBUFFORCE: 761 if (!capable(CAP_NET_ADMIN)) { 762 ret = -EPERM; 763 break; 764 } 765 goto set_rcvbuf; 766 767 case SO_KEEPALIVE: 768 #ifdef CONFIG_INET 769 if (sk->sk_protocol == IPPROTO_TCP && 770 sk->sk_type == SOCK_STREAM) 771 tcp_set_keepalive(sk, valbool); 772 #endif 773 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 774 break; 775 776 case SO_OOBINLINE: 777 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 778 break; 779 780 case SO_NO_CHECK: 781 sk->sk_no_check_tx = valbool; 782 break; 783 784 case SO_PRIORITY: 785 if ((val >= 0 && val <= 6) || 786 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 787 sk->sk_priority = val; 788 else 789 ret = -EPERM; 790 break; 791 792 case SO_LINGER: 793 if (optlen < sizeof(ling)) { 794 ret = -EINVAL; /* 1003.1g */ 795 break; 796 } 797 if (copy_from_user(&ling, optval, sizeof(ling))) { 798 ret = -EFAULT; 799 break; 800 } 801 if (!ling.l_onoff) 802 sock_reset_flag(sk, SOCK_LINGER); 803 else { 804 #if (BITS_PER_LONG == 32) 805 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 806 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 807 else 808 #endif 809 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 810 sock_set_flag(sk, SOCK_LINGER); 811 } 812 break; 813 814 case SO_BSDCOMPAT: 815 sock_warn_obsolete_bsdism("setsockopt"); 816 break; 817 818 case SO_PASSCRED: 819 if (valbool) 820 set_bit(SOCK_PASSCRED, &sock->flags); 821 else 822 clear_bit(SOCK_PASSCRED, &sock->flags); 823 break; 824 825 case SO_TIMESTAMP: 826 case SO_TIMESTAMPNS: 827 if (valbool) { 828 if (optname == SO_TIMESTAMP) 829 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 830 else 831 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 832 sock_set_flag(sk, SOCK_RCVTSTAMP); 833 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 834 } else { 835 sock_reset_flag(sk, SOCK_RCVTSTAMP); 836 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 837 } 838 break; 839 840 case SO_TIMESTAMPING: 841 if (val & ~SOF_TIMESTAMPING_MASK) { 842 ret = -EINVAL; 843 break; 844 } 845 846 if (val & SOF_TIMESTAMPING_OPT_ID && 847 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 848 if (sk->sk_protocol == IPPROTO_TCP) { 849 if (sk->sk_state != TCP_ESTABLISHED) { 850 ret = -EINVAL; 851 break; 852 } 853 sk->sk_tskey = tcp_sk(sk)->snd_una; 854 } else { 855 sk->sk_tskey = 0; 856 } 857 } 858 sk->sk_tsflags = val; 859 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 860 sock_enable_timestamp(sk, 861 SOCK_TIMESTAMPING_RX_SOFTWARE); 862 else 863 sock_disable_timestamp(sk, 864 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 865 break; 866 867 case SO_RCVLOWAT: 868 if (val < 0) 869 val = INT_MAX; 870 sk->sk_rcvlowat = val ? : 1; 871 break; 872 873 case SO_RCVTIMEO: 874 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 875 break; 876 877 case SO_SNDTIMEO: 878 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 879 break; 880 881 case SO_ATTACH_FILTER: 882 ret = -EINVAL; 883 if (optlen == sizeof(struct sock_fprog)) { 884 struct sock_fprog fprog; 885 886 ret = -EFAULT; 887 if (copy_from_user(&fprog, optval, sizeof(fprog))) 888 break; 889 890 ret = sk_attach_filter(&fprog, sk); 891 } 892 break; 893 894 case SO_ATTACH_BPF: 895 ret = -EINVAL; 896 if (optlen == sizeof(u32)) { 897 u32 ufd; 898 899 ret = -EFAULT; 900 if (copy_from_user(&ufd, optval, sizeof(ufd))) 901 break; 902 903 ret = sk_attach_bpf(ufd, sk); 904 } 905 break; 906 907 case SO_DETACH_FILTER: 908 ret = sk_detach_filter(sk); 909 break; 910 911 case SO_LOCK_FILTER: 912 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 913 ret = -EPERM; 914 else 915 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 916 break; 917 918 case SO_PASSSEC: 919 if (valbool) 920 set_bit(SOCK_PASSSEC, &sock->flags); 921 else 922 clear_bit(SOCK_PASSSEC, &sock->flags); 923 break; 924 case SO_MARK: 925 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 926 ret = -EPERM; 927 else 928 sk->sk_mark = val; 929 break; 930 931 /* We implement the SO_SNDLOWAT etc to 932 not be settable (1003.1g 5.3) */ 933 case SO_RXQ_OVFL: 934 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 935 break; 936 937 case SO_WIFI_STATUS: 938 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 939 break; 940 941 case SO_PEEK_OFF: 942 if (sock->ops->set_peek_off) 943 ret = sock->ops->set_peek_off(sk, val); 944 else 945 ret = -EOPNOTSUPP; 946 break; 947 948 case SO_NOFCS: 949 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 950 break; 951 952 case SO_SELECT_ERR_QUEUE: 953 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 954 break; 955 956 #ifdef CONFIG_NET_RX_BUSY_POLL 957 case SO_BUSY_POLL: 958 /* allow unprivileged users to decrease the value */ 959 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 960 ret = -EPERM; 961 else { 962 if (val < 0) 963 ret = -EINVAL; 964 else 965 sk->sk_ll_usec = val; 966 } 967 break; 968 #endif 969 970 case SO_MAX_PACING_RATE: 971 sk->sk_max_pacing_rate = val; 972 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 973 sk->sk_max_pacing_rate); 974 break; 975 976 default: 977 ret = -ENOPROTOOPT; 978 break; 979 } 980 release_sock(sk); 981 return ret; 982 } 983 EXPORT_SYMBOL(sock_setsockopt); 984 985 986 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 987 struct ucred *ucred) 988 { 989 ucred->pid = pid_vnr(pid); 990 ucred->uid = ucred->gid = -1; 991 if (cred) { 992 struct user_namespace *current_ns = current_user_ns(); 993 994 ucred->uid = from_kuid_munged(current_ns, cred->euid); 995 ucred->gid = from_kgid_munged(current_ns, cred->egid); 996 } 997 } 998 999 int sock_getsockopt(struct socket *sock, int level, int optname, 1000 char __user *optval, int __user *optlen) 1001 { 1002 struct sock *sk = sock->sk; 1003 1004 union { 1005 int val; 1006 struct linger ling; 1007 struct timeval tm; 1008 } v; 1009 1010 int lv = sizeof(int); 1011 int len; 1012 1013 if (get_user(len, optlen)) 1014 return -EFAULT; 1015 if (len < 0) 1016 return -EINVAL; 1017 1018 memset(&v, 0, sizeof(v)); 1019 1020 switch (optname) { 1021 case SO_DEBUG: 1022 v.val = sock_flag(sk, SOCK_DBG); 1023 break; 1024 1025 case SO_DONTROUTE: 1026 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1027 break; 1028 1029 case SO_BROADCAST: 1030 v.val = sock_flag(sk, SOCK_BROADCAST); 1031 break; 1032 1033 case SO_SNDBUF: 1034 v.val = sk->sk_sndbuf; 1035 break; 1036 1037 case SO_RCVBUF: 1038 v.val = sk->sk_rcvbuf; 1039 break; 1040 1041 case SO_REUSEADDR: 1042 v.val = sk->sk_reuse; 1043 break; 1044 1045 case SO_REUSEPORT: 1046 v.val = sk->sk_reuseport; 1047 break; 1048 1049 case SO_KEEPALIVE: 1050 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1051 break; 1052 1053 case SO_TYPE: 1054 v.val = sk->sk_type; 1055 break; 1056 1057 case SO_PROTOCOL: 1058 v.val = sk->sk_protocol; 1059 break; 1060 1061 case SO_DOMAIN: 1062 v.val = sk->sk_family; 1063 break; 1064 1065 case SO_ERROR: 1066 v.val = -sock_error(sk); 1067 if (v.val == 0) 1068 v.val = xchg(&sk->sk_err_soft, 0); 1069 break; 1070 1071 case SO_OOBINLINE: 1072 v.val = sock_flag(sk, SOCK_URGINLINE); 1073 break; 1074 1075 case SO_NO_CHECK: 1076 v.val = sk->sk_no_check_tx; 1077 break; 1078 1079 case SO_PRIORITY: 1080 v.val = sk->sk_priority; 1081 break; 1082 1083 case SO_LINGER: 1084 lv = sizeof(v.ling); 1085 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1086 v.ling.l_linger = sk->sk_lingertime / HZ; 1087 break; 1088 1089 case SO_BSDCOMPAT: 1090 sock_warn_obsolete_bsdism("getsockopt"); 1091 break; 1092 1093 case SO_TIMESTAMP: 1094 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1095 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1096 break; 1097 1098 case SO_TIMESTAMPNS: 1099 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1100 break; 1101 1102 case SO_TIMESTAMPING: 1103 v.val = sk->sk_tsflags; 1104 break; 1105 1106 case SO_RCVTIMEO: 1107 lv = sizeof(struct timeval); 1108 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1109 v.tm.tv_sec = 0; 1110 v.tm.tv_usec = 0; 1111 } else { 1112 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1113 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1114 } 1115 break; 1116 1117 case SO_SNDTIMEO: 1118 lv = sizeof(struct timeval); 1119 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1120 v.tm.tv_sec = 0; 1121 v.tm.tv_usec = 0; 1122 } else { 1123 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1124 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1125 } 1126 break; 1127 1128 case SO_RCVLOWAT: 1129 v.val = sk->sk_rcvlowat; 1130 break; 1131 1132 case SO_SNDLOWAT: 1133 v.val = 1; 1134 break; 1135 1136 case SO_PASSCRED: 1137 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1138 break; 1139 1140 case SO_PEERCRED: 1141 { 1142 struct ucred peercred; 1143 if (len > sizeof(peercred)) 1144 len = sizeof(peercred); 1145 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1146 if (copy_to_user(optval, &peercred, len)) 1147 return -EFAULT; 1148 goto lenout; 1149 } 1150 1151 case SO_PEERNAME: 1152 { 1153 char address[128]; 1154 1155 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1156 return -ENOTCONN; 1157 if (lv < len) 1158 return -EINVAL; 1159 if (copy_to_user(optval, address, len)) 1160 return -EFAULT; 1161 goto lenout; 1162 } 1163 1164 /* Dubious BSD thing... Probably nobody even uses it, but 1165 * the UNIX standard wants it for whatever reason... -DaveM 1166 */ 1167 case SO_ACCEPTCONN: 1168 v.val = sk->sk_state == TCP_LISTEN; 1169 break; 1170 1171 case SO_PASSSEC: 1172 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1173 break; 1174 1175 case SO_PEERSEC: 1176 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1177 1178 case SO_MARK: 1179 v.val = sk->sk_mark; 1180 break; 1181 1182 case SO_RXQ_OVFL: 1183 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1184 break; 1185 1186 case SO_WIFI_STATUS: 1187 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1188 break; 1189 1190 case SO_PEEK_OFF: 1191 if (!sock->ops->set_peek_off) 1192 return -EOPNOTSUPP; 1193 1194 v.val = sk->sk_peek_off; 1195 break; 1196 case SO_NOFCS: 1197 v.val = sock_flag(sk, SOCK_NOFCS); 1198 break; 1199 1200 case SO_BINDTODEVICE: 1201 return sock_getbindtodevice(sk, optval, optlen, len); 1202 1203 case SO_GET_FILTER: 1204 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1205 if (len < 0) 1206 return len; 1207 1208 goto lenout; 1209 1210 case SO_LOCK_FILTER: 1211 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1212 break; 1213 1214 case SO_BPF_EXTENSIONS: 1215 v.val = bpf_tell_extensions(); 1216 break; 1217 1218 case SO_SELECT_ERR_QUEUE: 1219 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1220 break; 1221 1222 #ifdef CONFIG_NET_RX_BUSY_POLL 1223 case SO_BUSY_POLL: 1224 v.val = sk->sk_ll_usec; 1225 break; 1226 #endif 1227 1228 case SO_MAX_PACING_RATE: 1229 v.val = sk->sk_max_pacing_rate; 1230 break; 1231 1232 case SO_INCOMING_CPU: 1233 v.val = sk->sk_incoming_cpu; 1234 break; 1235 1236 default: 1237 return -ENOPROTOOPT; 1238 } 1239 1240 if (len > lv) 1241 len = lv; 1242 if (copy_to_user(optval, &v, len)) 1243 return -EFAULT; 1244 lenout: 1245 if (put_user(len, optlen)) 1246 return -EFAULT; 1247 return 0; 1248 } 1249 1250 /* 1251 * Initialize an sk_lock. 1252 * 1253 * (We also register the sk_lock with the lock validator.) 1254 */ 1255 static inline void sock_lock_init(struct sock *sk) 1256 { 1257 sock_lock_init_class_and_name(sk, 1258 af_family_slock_key_strings[sk->sk_family], 1259 af_family_slock_keys + sk->sk_family, 1260 af_family_key_strings[sk->sk_family], 1261 af_family_keys + sk->sk_family); 1262 } 1263 1264 /* 1265 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1266 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1267 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1268 */ 1269 static void sock_copy(struct sock *nsk, const struct sock *osk) 1270 { 1271 #ifdef CONFIG_SECURITY_NETWORK 1272 void *sptr = nsk->sk_security; 1273 #endif 1274 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1275 1276 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1277 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1278 1279 #ifdef CONFIG_SECURITY_NETWORK 1280 nsk->sk_security = sptr; 1281 security_sk_clone(osk, nsk); 1282 #endif 1283 } 1284 1285 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1286 { 1287 unsigned long nulls1, nulls2; 1288 1289 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1290 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1291 if (nulls1 > nulls2) 1292 swap(nulls1, nulls2); 1293 1294 if (nulls1 != 0) 1295 memset((char *)sk, 0, nulls1); 1296 memset((char *)sk + nulls1 + sizeof(void *), 0, 1297 nulls2 - nulls1 - sizeof(void *)); 1298 memset((char *)sk + nulls2 + sizeof(void *), 0, 1299 size - nulls2 - sizeof(void *)); 1300 } 1301 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1302 1303 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1304 int family) 1305 { 1306 struct sock *sk; 1307 struct kmem_cache *slab; 1308 1309 slab = prot->slab; 1310 if (slab != NULL) { 1311 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1312 if (!sk) 1313 return sk; 1314 if (priority & __GFP_ZERO) { 1315 if (prot->clear_sk) 1316 prot->clear_sk(sk, prot->obj_size); 1317 else 1318 sk_prot_clear_nulls(sk, prot->obj_size); 1319 } 1320 } else 1321 sk = kmalloc(prot->obj_size, priority); 1322 1323 if (sk != NULL) { 1324 kmemcheck_annotate_bitfield(sk, flags); 1325 1326 if (security_sk_alloc(sk, family, priority)) 1327 goto out_free; 1328 1329 if (!try_module_get(prot->owner)) 1330 goto out_free_sec; 1331 sk_tx_queue_clear(sk); 1332 } 1333 1334 return sk; 1335 1336 out_free_sec: 1337 security_sk_free(sk); 1338 out_free: 1339 if (slab != NULL) 1340 kmem_cache_free(slab, sk); 1341 else 1342 kfree(sk); 1343 return NULL; 1344 } 1345 1346 static void sk_prot_free(struct proto *prot, struct sock *sk) 1347 { 1348 struct kmem_cache *slab; 1349 struct module *owner; 1350 1351 owner = prot->owner; 1352 slab = prot->slab; 1353 1354 security_sk_free(sk); 1355 if (slab != NULL) 1356 kmem_cache_free(slab, sk); 1357 else 1358 kfree(sk); 1359 module_put(owner); 1360 } 1361 1362 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 1363 void sock_update_netprioidx(struct sock *sk) 1364 { 1365 if (in_interrupt()) 1366 return; 1367 1368 sk->sk_cgrp_prioidx = task_netprioidx(current); 1369 } 1370 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1371 #endif 1372 1373 /** 1374 * sk_alloc - All socket objects are allocated here 1375 * @net: the applicable net namespace 1376 * @family: protocol family 1377 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1378 * @prot: struct proto associated with this new sock instance 1379 */ 1380 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1381 struct proto *prot) 1382 { 1383 struct sock *sk; 1384 1385 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1386 if (sk) { 1387 sk->sk_family = family; 1388 /* 1389 * See comment in struct sock definition to understand 1390 * why we need sk_prot_creator -acme 1391 */ 1392 sk->sk_prot = sk->sk_prot_creator = prot; 1393 sock_lock_init(sk); 1394 sock_net_set(sk, get_net(net)); 1395 atomic_set(&sk->sk_wmem_alloc, 1); 1396 1397 sock_update_classid(sk); 1398 sock_update_netprioidx(sk); 1399 } 1400 1401 return sk; 1402 } 1403 EXPORT_SYMBOL(sk_alloc); 1404 1405 static void __sk_free(struct sock *sk) 1406 { 1407 struct sk_filter *filter; 1408 1409 if (sk->sk_destruct) 1410 sk->sk_destruct(sk); 1411 1412 filter = rcu_dereference_check(sk->sk_filter, 1413 atomic_read(&sk->sk_wmem_alloc) == 0); 1414 if (filter) { 1415 sk_filter_uncharge(sk, filter); 1416 RCU_INIT_POINTER(sk->sk_filter, NULL); 1417 } 1418 1419 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1420 1421 if (atomic_read(&sk->sk_omem_alloc)) 1422 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1423 __func__, atomic_read(&sk->sk_omem_alloc)); 1424 1425 if (sk->sk_peer_cred) 1426 put_cred(sk->sk_peer_cred); 1427 put_pid(sk->sk_peer_pid); 1428 put_net(sock_net(sk)); 1429 sk_prot_free(sk->sk_prot_creator, sk); 1430 } 1431 1432 void sk_free(struct sock *sk) 1433 { 1434 /* 1435 * We subtract one from sk_wmem_alloc and can know if 1436 * some packets are still in some tx queue. 1437 * If not null, sock_wfree() will call __sk_free(sk) later 1438 */ 1439 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1440 __sk_free(sk); 1441 } 1442 EXPORT_SYMBOL(sk_free); 1443 1444 /* 1445 * Last sock_put should drop reference to sk->sk_net. It has already 1446 * been dropped in sk_change_net. Taking reference to stopping namespace 1447 * is not an option. 1448 * Take reference to a socket to remove it from hash _alive_ and after that 1449 * destroy it in the context of init_net. 1450 */ 1451 void sk_release_kernel(struct sock *sk) 1452 { 1453 if (sk == NULL || sk->sk_socket == NULL) 1454 return; 1455 1456 sock_hold(sk); 1457 sock_release(sk->sk_socket); 1458 release_net(sock_net(sk)); 1459 sock_net_set(sk, get_net(&init_net)); 1460 sock_put(sk); 1461 } 1462 EXPORT_SYMBOL(sk_release_kernel); 1463 1464 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1465 { 1466 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1467 sock_update_memcg(newsk); 1468 } 1469 1470 /** 1471 * sk_clone_lock - clone a socket, and lock its clone 1472 * @sk: the socket to clone 1473 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1474 * 1475 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1476 */ 1477 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1478 { 1479 struct sock *newsk; 1480 bool is_charged = true; 1481 1482 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1483 if (newsk != NULL) { 1484 struct sk_filter *filter; 1485 1486 sock_copy(newsk, sk); 1487 1488 /* SANITY */ 1489 get_net(sock_net(newsk)); 1490 sk_node_init(&newsk->sk_node); 1491 sock_lock_init(newsk); 1492 bh_lock_sock(newsk); 1493 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1494 newsk->sk_backlog.len = 0; 1495 1496 atomic_set(&newsk->sk_rmem_alloc, 0); 1497 /* 1498 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1499 */ 1500 atomic_set(&newsk->sk_wmem_alloc, 1); 1501 atomic_set(&newsk->sk_omem_alloc, 0); 1502 skb_queue_head_init(&newsk->sk_receive_queue); 1503 skb_queue_head_init(&newsk->sk_write_queue); 1504 1505 spin_lock_init(&newsk->sk_dst_lock); 1506 rwlock_init(&newsk->sk_callback_lock); 1507 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1508 af_callback_keys + newsk->sk_family, 1509 af_family_clock_key_strings[newsk->sk_family]); 1510 1511 newsk->sk_dst_cache = NULL; 1512 newsk->sk_wmem_queued = 0; 1513 newsk->sk_forward_alloc = 0; 1514 newsk->sk_send_head = NULL; 1515 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1516 1517 sock_reset_flag(newsk, SOCK_DONE); 1518 skb_queue_head_init(&newsk->sk_error_queue); 1519 1520 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1521 if (filter != NULL) 1522 /* though it's an empty new sock, the charging may fail 1523 * if sysctl_optmem_max was changed between creation of 1524 * original socket and cloning 1525 */ 1526 is_charged = sk_filter_charge(newsk, filter); 1527 1528 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) { 1529 /* It is still raw copy of parent, so invalidate 1530 * destructor and make plain sk_free() */ 1531 newsk->sk_destruct = NULL; 1532 bh_unlock_sock(newsk); 1533 sk_free(newsk); 1534 newsk = NULL; 1535 goto out; 1536 } 1537 1538 newsk->sk_err = 0; 1539 newsk->sk_priority = 0; 1540 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1541 atomic64_set(&newsk->sk_cookie, 0); 1542 /* 1543 * Before updating sk_refcnt, we must commit prior changes to memory 1544 * (Documentation/RCU/rculist_nulls.txt for details) 1545 */ 1546 smp_wmb(); 1547 atomic_set(&newsk->sk_refcnt, 2); 1548 1549 /* 1550 * Increment the counter in the same struct proto as the master 1551 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1552 * is the same as sk->sk_prot->socks, as this field was copied 1553 * with memcpy). 1554 * 1555 * This _changes_ the previous behaviour, where 1556 * tcp_create_openreq_child always was incrementing the 1557 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1558 * to be taken into account in all callers. -acme 1559 */ 1560 sk_refcnt_debug_inc(newsk); 1561 sk_set_socket(newsk, NULL); 1562 newsk->sk_wq = NULL; 1563 1564 sk_update_clone(sk, newsk); 1565 1566 if (newsk->sk_prot->sockets_allocated) 1567 sk_sockets_allocated_inc(newsk); 1568 1569 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1570 net_enable_timestamp(); 1571 } 1572 out: 1573 return newsk; 1574 } 1575 EXPORT_SYMBOL_GPL(sk_clone_lock); 1576 1577 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1578 { 1579 __sk_dst_set(sk, dst); 1580 sk->sk_route_caps = dst->dev->features; 1581 if (sk->sk_route_caps & NETIF_F_GSO) 1582 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1583 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1584 if (sk_can_gso(sk)) { 1585 if (dst->header_len) { 1586 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1587 } else { 1588 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1589 sk->sk_gso_max_size = dst->dev->gso_max_size; 1590 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1591 } 1592 } 1593 } 1594 EXPORT_SYMBOL_GPL(sk_setup_caps); 1595 1596 /* 1597 * Simple resource managers for sockets. 1598 */ 1599 1600 1601 /* 1602 * Write buffer destructor automatically called from kfree_skb. 1603 */ 1604 void sock_wfree(struct sk_buff *skb) 1605 { 1606 struct sock *sk = skb->sk; 1607 unsigned int len = skb->truesize; 1608 1609 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1610 /* 1611 * Keep a reference on sk_wmem_alloc, this will be released 1612 * after sk_write_space() call 1613 */ 1614 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1615 sk->sk_write_space(sk); 1616 len = 1; 1617 } 1618 /* 1619 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1620 * could not do because of in-flight packets 1621 */ 1622 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1623 __sk_free(sk); 1624 } 1625 EXPORT_SYMBOL(sock_wfree); 1626 1627 void skb_orphan_partial(struct sk_buff *skb) 1628 { 1629 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1630 * so we do not completely orphan skb, but transfert all 1631 * accounted bytes but one, to avoid unexpected reorders. 1632 */ 1633 if (skb->destructor == sock_wfree 1634 #ifdef CONFIG_INET 1635 || skb->destructor == tcp_wfree 1636 #endif 1637 ) { 1638 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1639 skb->truesize = 1; 1640 } else { 1641 skb_orphan(skb); 1642 } 1643 } 1644 EXPORT_SYMBOL(skb_orphan_partial); 1645 1646 /* 1647 * Read buffer destructor automatically called from kfree_skb. 1648 */ 1649 void sock_rfree(struct sk_buff *skb) 1650 { 1651 struct sock *sk = skb->sk; 1652 unsigned int len = skb->truesize; 1653 1654 atomic_sub(len, &sk->sk_rmem_alloc); 1655 sk_mem_uncharge(sk, len); 1656 } 1657 EXPORT_SYMBOL(sock_rfree); 1658 1659 void sock_efree(struct sk_buff *skb) 1660 { 1661 sock_put(skb->sk); 1662 } 1663 EXPORT_SYMBOL(sock_efree); 1664 1665 #ifdef CONFIG_INET 1666 void sock_edemux(struct sk_buff *skb) 1667 { 1668 struct sock *sk = skb->sk; 1669 1670 if (sk->sk_state == TCP_TIME_WAIT) 1671 inet_twsk_put(inet_twsk(sk)); 1672 else 1673 sock_put(sk); 1674 } 1675 EXPORT_SYMBOL(sock_edemux); 1676 #endif 1677 1678 kuid_t sock_i_uid(struct sock *sk) 1679 { 1680 kuid_t uid; 1681 1682 read_lock_bh(&sk->sk_callback_lock); 1683 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1684 read_unlock_bh(&sk->sk_callback_lock); 1685 return uid; 1686 } 1687 EXPORT_SYMBOL(sock_i_uid); 1688 1689 unsigned long sock_i_ino(struct sock *sk) 1690 { 1691 unsigned long ino; 1692 1693 read_lock_bh(&sk->sk_callback_lock); 1694 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1695 read_unlock_bh(&sk->sk_callback_lock); 1696 return ino; 1697 } 1698 EXPORT_SYMBOL(sock_i_ino); 1699 1700 /* 1701 * Allocate a skb from the socket's send buffer. 1702 */ 1703 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1704 gfp_t priority) 1705 { 1706 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1707 struct sk_buff *skb = alloc_skb(size, priority); 1708 if (skb) { 1709 skb_set_owner_w(skb, sk); 1710 return skb; 1711 } 1712 } 1713 return NULL; 1714 } 1715 EXPORT_SYMBOL(sock_wmalloc); 1716 1717 /* 1718 * Allocate a memory block from the socket's option memory buffer. 1719 */ 1720 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1721 { 1722 if ((unsigned int)size <= sysctl_optmem_max && 1723 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1724 void *mem; 1725 /* First do the add, to avoid the race if kmalloc 1726 * might sleep. 1727 */ 1728 atomic_add(size, &sk->sk_omem_alloc); 1729 mem = kmalloc(size, priority); 1730 if (mem) 1731 return mem; 1732 atomic_sub(size, &sk->sk_omem_alloc); 1733 } 1734 return NULL; 1735 } 1736 EXPORT_SYMBOL(sock_kmalloc); 1737 1738 /* Free an option memory block. Note, we actually want the inline 1739 * here as this allows gcc to detect the nullify and fold away the 1740 * condition entirely. 1741 */ 1742 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 1743 const bool nullify) 1744 { 1745 if (WARN_ON_ONCE(!mem)) 1746 return; 1747 if (nullify) 1748 kzfree(mem); 1749 else 1750 kfree(mem); 1751 atomic_sub(size, &sk->sk_omem_alloc); 1752 } 1753 1754 void sock_kfree_s(struct sock *sk, void *mem, int size) 1755 { 1756 __sock_kfree_s(sk, mem, size, false); 1757 } 1758 EXPORT_SYMBOL(sock_kfree_s); 1759 1760 void sock_kzfree_s(struct sock *sk, void *mem, int size) 1761 { 1762 __sock_kfree_s(sk, mem, size, true); 1763 } 1764 EXPORT_SYMBOL(sock_kzfree_s); 1765 1766 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1767 I think, these locks should be removed for datagram sockets. 1768 */ 1769 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1770 { 1771 DEFINE_WAIT(wait); 1772 1773 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1774 for (;;) { 1775 if (!timeo) 1776 break; 1777 if (signal_pending(current)) 1778 break; 1779 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1780 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1781 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1782 break; 1783 if (sk->sk_shutdown & SEND_SHUTDOWN) 1784 break; 1785 if (sk->sk_err) 1786 break; 1787 timeo = schedule_timeout(timeo); 1788 } 1789 finish_wait(sk_sleep(sk), &wait); 1790 return timeo; 1791 } 1792 1793 1794 /* 1795 * Generic send/receive buffer handlers 1796 */ 1797 1798 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1799 unsigned long data_len, int noblock, 1800 int *errcode, int max_page_order) 1801 { 1802 struct sk_buff *skb; 1803 long timeo; 1804 int err; 1805 1806 timeo = sock_sndtimeo(sk, noblock); 1807 for (;;) { 1808 err = sock_error(sk); 1809 if (err != 0) 1810 goto failure; 1811 1812 err = -EPIPE; 1813 if (sk->sk_shutdown & SEND_SHUTDOWN) 1814 goto failure; 1815 1816 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 1817 break; 1818 1819 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1820 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1821 err = -EAGAIN; 1822 if (!timeo) 1823 goto failure; 1824 if (signal_pending(current)) 1825 goto interrupted; 1826 timeo = sock_wait_for_wmem(sk, timeo); 1827 } 1828 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 1829 errcode, sk->sk_allocation); 1830 if (skb) 1831 skb_set_owner_w(skb, sk); 1832 return skb; 1833 1834 interrupted: 1835 err = sock_intr_errno(timeo); 1836 failure: 1837 *errcode = err; 1838 return NULL; 1839 } 1840 EXPORT_SYMBOL(sock_alloc_send_pskb); 1841 1842 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1843 int noblock, int *errcode) 1844 { 1845 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1846 } 1847 EXPORT_SYMBOL(sock_alloc_send_skb); 1848 1849 /* On 32bit arches, an skb frag is limited to 2^15 */ 1850 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1851 1852 /** 1853 * skb_page_frag_refill - check that a page_frag contains enough room 1854 * @sz: minimum size of the fragment we want to get 1855 * @pfrag: pointer to page_frag 1856 * @gfp: priority for memory allocation 1857 * 1858 * Note: While this allocator tries to use high order pages, there is 1859 * no guarantee that allocations succeed. Therefore, @sz MUST be 1860 * less or equal than PAGE_SIZE. 1861 */ 1862 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 1863 { 1864 if (pfrag->page) { 1865 if (atomic_read(&pfrag->page->_count) == 1) { 1866 pfrag->offset = 0; 1867 return true; 1868 } 1869 if (pfrag->offset + sz <= pfrag->size) 1870 return true; 1871 put_page(pfrag->page); 1872 } 1873 1874 pfrag->offset = 0; 1875 if (SKB_FRAG_PAGE_ORDER) { 1876 pfrag->page = alloc_pages(gfp | __GFP_COMP | 1877 __GFP_NOWARN | __GFP_NORETRY, 1878 SKB_FRAG_PAGE_ORDER); 1879 if (likely(pfrag->page)) { 1880 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 1881 return true; 1882 } 1883 } 1884 pfrag->page = alloc_page(gfp); 1885 if (likely(pfrag->page)) { 1886 pfrag->size = PAGE_SIZE; 1887 return true; 1888 } 1889 return false; 1890 } 1891 EXPORT_SYMBOL(skb_page_frag_refill); 1892 1893 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1894 { 1895 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1896 return true; 1897 1898 sk_enter_memory_pressure(sk); 1899 sk_stream_moderate_sndbuf(sk); 1900 return false; 1901 } 1902 EXPORT_SYMBOL(sk_page_frag_refill); 1903 1904 static void __lock_sock(struct sock *sk) 1905 __releases(&sk->sk_lock.slock) 1906 __acquires(&sk->sk_lock.slock) 1907 { 1908 DEFINE_WAIT(wait); 1909 1910 for (;;) { 1911 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1912 TASK_UNINTERRUPTIBLE); 1913 spin_unlock_bh(&sk->sk_lock.slock); 1914 schedule(); 1915 spin_lock_bh(&sk->sk_lock.slock); 1916 if (!sock_owned_by_user(sk)) 1917 break; 1918 } 1919 finish_wait(&sk->sk_lock.wq, &wait); 1920 } 1921 1922 static void __release_sock(struct sock *sk) 1923 __releases(&sk->sk_lock.slock) 1924 __acquires(&sk->sk_lock.slock) 1925 { 1926 struct sk_buff *skb = sk->sk_backlog.head; 1927 1928 do { 1929 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1930 bh_unlock_sock(sk); 1931 1932 do { 1933 struct sk_buff *next = skb->next; 1934 1935 prefetch(next); 1936 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1937 skb->next = NULL; 1938 sk_backlog_rcv(sk, skb); 1939 1940 /* 1941 * We are in process context here with softirqs 1942 * disabled, use cond_resched_softirq() to preempt. 1943 * This is safe to do because we've taken the backlog 1944 * queue private: 1945 */ 1946 cond_resched_softirq(); 1947 1948 skb = next; 1949 } while (skb != NULL); 1950 1951 bh_lock_sock(sk); 1952 } while ((skb = sk->sk_backlog.head) != NULL); 1953 1954 /* 1955 * Doing the zeroing here guarantee we can not loop forever 1956 * while a wild producer attempts to flood us. 1957 */ 1958 sk->sk_backlog.len = 0; 1959 } 1960 1961 /** 1962 * sk_wait_data - wait for data to arrive at sk_receive_queue 1963 * @sk: sock to wait on 1964 * @timeo: for how long 1965 * 1966 * Now socket state including sk->sk_err is changed only under lock, 1967 * hence we may omit checks after joining wait queue. 1968 * We check receive queue before schedule() only as optimization; 1969 * it is very likely that release_sock() added new data. 1970 */ 1971 int sk_wait_data(struct sock *sk, long *timeo) 1972 { 1973 int rc; 1974 DEFINE_WAIT(wait); 1975 1976 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1977 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1978 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1979 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1980 finish_wait(sk_sleep(sk), &wait); 1981 return rc; 1982 } 1983 EXPORT_SYMBOL(sk_wait_data); 1984 1985 /** 1986 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1987 * @sk: socket 1988 * @size: memory size to allocate 1989 * @kind: allocation type 1990 * 1991 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1992 * rmem allocation. This function assumes that protocols which have 1993 * memory_pressure use sk_wmem_queued as write buffer accounting. 1994 */ 1995 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1996 { 1997 struct proto *prot = sk->sk_prot; 1998 int amt = sk_mem_pages(size); 1999 long allocated; 2000 int parent_status = UNDER_LIMIT; 2001 2002 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 2003 2004 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 2005 2006 /* Under limit. */ 2007 if (parent_status == UNDER_LIMIT && 2008 allocated <= sk_prot_mem_limits(sk, 0)) { 2009 sk_leave_memory_pressure(sk); 2010 return 1; 2011 } 2012 2013 /* Under pressure. (we or our parents) */ 2014 if ((parent_status > SOFT_LIMIT) || 2015 allocated > sk_prot_mem_limits(sk, 1)) 2016 sk_enter_memory_pressure(sk); 2017 2018 /* Over hard limit (we or our parents) */ 2019 if ((parent_status == OVER_LIMIT) || 2020 (allocated > sk_prot_mem_limits(sk, 2))) 2021 goto suppress_allocation; 2022 2023 /* guarantee minimum buffer size under pressure */ 2024 if (kind == SK_MEM_RECV) { 2025 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2026 return 1; 2027 2028 } else { /* SK_MEM_SEND */ 2029 if (sk->sk_type == SOCK_STREAM) { 2030 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2031 return 1; 2032 } else if (atomic_read(&sk->sk_wmem_alloc) < 2033 prot->sysctl_wmem[0]) 2034 return 1; 2035 } 2036 2037 if (sk_has_memory_pressure(sk)) { 2038 int alloc; 2039 2040 if (!sk_under_memory_pressure(sk)) 2041 return 1; 2042 alloc = sk_sockets_allocated_read_positive(sk); 2043 if (sk_prot_mem_limits(sk, 2) > alloc * 2044 sk_mem_pages(sk->sk_wmem_queued + 2045 atomic_read(&sk->sk_rmem_alloc) + 2046 sk->sk_forward_alloc)) 2047 return 1; 2048 } 2049 2050 suppress_allocation: 2051 2052 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2053 sk_stream_moderate_sndbuf(sk); 2054 2055 /* Fail only if socket is _under_ its sndbuf. 2056 * In this case we cannot block, so that we have to fail. 2057 */ 2058 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2059 return 1; 2060 } 2061 2062 trace_sock_exceed_buf_limit(sk, prot, allocated); 2063 2064 /* Alas. Undo changes. */ 2065 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2066 2067 sk_memory_allocated_sub(sk, amt); 2068 2069 return 0; 2070 } 2071 EXPORT_SYMBOL(__sk_mem_schedule); 2072 2073 /** 2074 * __sk_reclaim - reclaim memory_allocated 2075 * @sk: socket 2076 */ 2077 void __sk_mem_reclaim(struct sock *sk) 2078 { 2079 sk_memory_allocated_sub(sk, 2080 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2081 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2082 2083 if (sk_under_memory_pressure(sk) && 2084 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2085 sk_leave_memory_pressure(sk); 2086 } 2087 EXPORT_SYMBOL(__sk_mem_reclaim); 2088 2089 2090 /* 2091 * Set of default routines for initialising struct proto_ops when 2092 * the protocol does not support a particular function. In certain 2093 * cases where it makes no sense for a protocol to have a "do nothing" 2094 * function, some default processing is provided. 2095 */ 2096 2097 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2098 { 2099 return -EOPNOTSUPP; 2100 } 2101 EXPORT_SYMBOL(sock_no_bind); 2102 2103 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2104 int len, int flags) 2105 { 2106 return -EOPNOTSUPP; 2107 } 2108 EXPORT_SYMBOL(sock_no_connect); 2109 2110 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2111 { 2112 return -EOPNOTSUPP; 2113 } 2114 EXPORT_SYMBOL(sock_no_socketpair); 2115 2116 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2117 { 2118 return -EOPNOTSUPP; 2119 } 2120 EXPORT_SYMBOL(sock_no_accept); 2121 2122 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2123 int *len, int peer) 2124 { 2125 return -EOPNOTSUPP; 2126 } 2127 EXPORT_SYMBOL(sock_no_getname); 2128 2129 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2130 { 2131 return 0; 2132 } 2133 EXPORT_SYMBOL(sock_no_poll); 2134 2135 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2136 { 2137 return -EOPNOTSUPP; 2138 } 2139 EXPORT_SYMBOL(sock_no_ioctl); 2140 2141 int sock_no_listen(struct socket *sock, int backlog) 2142 { 2143 return -EOPNOTSUPP; 2144 } 2145 EXPORT_SYMBOL(sock_no_listen); 2146 2147 int sock_no_shutdown(struct socket *sock, int how) 2148 { 2149 return -EOPNOTSUPP; 2150 } 2151 EXPORT_SYMBOL(sock_no_shutdown); 2152 2153 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2154 char __user *optval, unsigned int optlen) 2155 { 2156 return -EOPNOTSUPP; 2157 } 2158 EXPORT_SYMBOL(sock_no_setsockopt); 2159 2160 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2161 char __user *optval, int __user *optlen) 2162 { 2163 return -EOPNOTSUPP; 2164 } 2165 EXPORT_SYMBOL(sock_no_getsockopt); 2166 2167 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2168 { 2169 return -EOPNOTSUPP; 2170 } 2171 EXPORT_SYMBOL(sock_no_sendmsg); 2172 2173 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2174 int flags) 2175 { 2176 return -EOPNOTSUPP; 2177 } 2178 EXPORT_SYMBOL(sock_no_recvmsg); 2179 2180 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2181 { 2182 /* Mirror missing mmap method error code */ 2183 return -ENODEV; 2184 } 2185 EXPORT_SYMBOL(sock_no_mmap); 2186 2187 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2188 { 2189 ssize_t res; 2190 struct msghdr msg = {.msg_flags = flags}; 2191 struct kvec iov; 2192 char *kaddr = kmap(page); 2193 iov.iov_base = kaddr + offset; 2194 iov.iov_len = size; 2195 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2196 kunmap(page); 2197 return res; 2198 } 2199 EXPORT_SYMBOL(sock_no_sendpage); 2200 2201 /* 2202 * Default Socket Callbacks 2203 */ 2204 2205 static void sock_def_wakeup(struct sock *sk) 2206 { 2207 struct socket_wq *wq; 2208 2209 rcu_read_lock(); 2210 wq = rcu_dereference(sk->sk_wq); 2211 if (wq_has_sleeper(wq)) 2212 wake_up_interruptible_all(&wq->wait); 2213 rcu_read_unlock(); 2214 } 2215 2216 static void sock_def_error_report(struct sock *sk) 2217 { 2218 struct socket_wq *wq; 2219 2220 rcu_read_lock(); 2221 wq = rcu_dereference(sk->sk_wq); 2222 if (wq_has_sleeper(wq)) 2223 wake_up_interruptible_poll(&wq->wait, POLLERR); 2224 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2225 rcu_read_unlock(); 2226 } 2227 2228 static void sock_def_readable(struct sock *sk) 2229 { 2230 struct socket_wq *wq; 2231 2232 rcu_read_lock(); 2233 wq = rcu_dereference(sk->sk_wq); 2234 if (wq_has_sleeper(wq)) 2235 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2236 POLLRDNORM | POLLRDBAND); 2237 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2238 rcu_read_unlock(); 2239 } 2240 2241 static void sock_def_write_space(struct sock *sk) 2242 { 2243 struct socket_wq *wq; 2244 2245 rcu_read_lock(); 2246 2247 /* Do not wake up a writer until he can make "significant" 2248 * progress. --DaveM 2249 */ 2250 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2251 wq = rcu_dereference(sk->sk_wq); 2252 if (wq_has_sleeper(wq)) 2253 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2254 POLLWRNORM | POLLWRBAND); 2255 2256 /* Should agree with poll, otherwise some programs break */ 2257 if (sock_writeable(sk)) 2258 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2259 } 2260 2261 rcu_read_unlock(); 2262 } 2263 2264 static void sock_def_destruct(struct sock *sk) 2265 { 2266 kfree(sk->sk_protinfo); 2267 } 2268 2269 void sk_send_sigurg(struct sock *sk) 2270 { 2271 if (sk->sk_socket && sk->sk_socket->file) 2272 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2273 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2274 } 2275 EXPORT_SYMBOL(sk_send_sigurg); 2276 2277 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2278 unsigned long expires) 2279 { 2280 if (!mod_timer(timer, expires)) 2281 sock_hold(sk); 2282 } 2283 EXPORT_SYMBOL(sk_reset_timer); 2284 2285 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2286 { 2287 if (del_timer(timer)) 2288 __sock_put(sk); 2289 } 2290 EXPORT_SYMBOL(sk_stop_timer); 2291 2292 void sock_init_data(struct socket *sock, struct sock *sk) 2293 { 2294 skb_queue_head_init(&sk->sk_receive_queue); 2295 skb_queue_head_init(&sk->sk_write_queue); 2296 skb_queue_head_init(&sk->sk_error_queue); 2297 2298 sk->sk_send_head = NULL; 2299 2300 init_timer(&sk->sk_timer); 2301 2302 sk->sk_allocation = GFP_KERNEL; 2303 sk->sk_rcvbuf = sysctl_rmem_default; 2304 sk->sk_sndbuf = sysctl_wmem_default; 2305 sk->sk_state = TCP_CLOSE; 2306 sk_set_socket(sk, sock); 2307 2308 sock_set_flag(sk, SOCK_ZAPPED); 2309 2310 if (sock) { 2311 sk->sk_type = sock->type; 2312 sk->sk_wq = sock->wq; 2313 sock->sk = sk; 2314 } else 2315 sk->sk_wq = NULL; 2316 2317 spin_lock_init(&sk->sk_dst_lock); 2318 rwlock_init(&sk->sk_callback_lock); 2319 lockdep_set_class_and_name(&sk->sk_callback_lock, 2320 af_callback_keys + sk->sk_family, 2321 af_family_clock_key_strings[sk->sk_family]); 2322 2323 sk->sk_state_change = sock_def_wakeup; 2324 sk->sk_data_ready = sock_def_readable; 2325 sk->sk_write_space = sock_def_write_space; 2326 sk->sk_error_report = sock_def_error_report; 2327 sk->sk_destruct = sock_def_destruct; 2328 2329 sk->sk_frag.page = NULL; 2330 sk->sk_frag.offset = 0; 2331 sk->sk_peek_off = -1; 2332 2333 sk->sk_peer_pid = NULL; 2334 sk->sk_peer_cred = NULL; 2335 sk->sk_write_pending = 0; 2336 sk->sk_rcvlowat = 1; 2337 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2338 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2339 2340 sk->sk_stamp = ktime_set(-1L, 0); 2341 2342 #ifdef CONFIG_NET_RX_BUSY_POLL 2343 sk->sk_napi_id = 0; 2344 sk->sk_ll_usec = sysctl_net_busy_read; 2345 #endif 2346 2347 sk->sk_max_pacing_rate = ~0U; 2348 sk->sk_pacing_rate = ~0U; 2349 /* 2350 * Before updating sk_refcnt, we must commit prior changes to memory 2351 * (Documentation/RCU/rculist_nulls.txt for details) 2352 */ 2353 smp_wmb(); 2354 atomic_set(&sk->sk_refcnt, 1); 2355 atomic_set(&sk->sk_drops, 0); 2356 } 2357 EXPORT_SYMBOL(sock_init_data); 2358 2359 void lock_sock_nested(struct sock *sk, int subclass) 2360 { 2361 might_sleep(); 2362 spin_lock_bh(&sk->sk_lock.slock); 2363 if (sk->sk_lock.owned) 2364 __lock_sock(sk); 2365 sk->sk_lock.owned = 1; 2366 spin_unlock(&sk->sk_lock.slock); 2367 /* 2368 * The sk_lock has mutex_lock() semantics here: 2369 */ 2370 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2371 local_bh_enable(); 2372 } 2373 EXPORT_SYMBOL(lock_sock_nested); 2374 2375 void release_sock(struct sock *sk) 2376 { 2377 /* 2378 * The sk_lock has mutex_unlock() semantics: 2379 */ 2380 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2381 2382 spin_lock_bh(&sk->sk_lock.slock); 2383 if (sk->sk_backlog.tail) 2384 __release_sock(sk); 2385 2386 /* Warning : release_cb() might need to release sk ownership, 2387 * ie call sock_release_ownership(sk) before us. 2388 */ 2389 if (sk->sk_prot->release_cb) 2390 sk->sk_prot->release_cb(sk); 2391 2392 sock_release_ownership(sk); 2393 if (waitqueue_active(&sk->sk_lock.wq)) 2394 wake_up(&sk->sk_lock.wq); 2395 spin_unlock_bh(&sk->sk_lock.slock); 2396 } 2397 EXPORT_SYMBOL(release_sock); 2398 2399 /** 2400 * lock_sock_fast - fast version of lock_sock 2401 * @sk: socket 2402 * 2403 * This version should be used for very small section, where process wont block 2404 * return false if fast path is taken 2405 * sk_lock.slock locked, owned = 0, BH disabled 2406 * return true if slow path is taken 2407 * sk_lock.slock unlocked, owned = 1, BH enabled 2408 */ 2409 bool lock_sock_fast(struct sock *sk) 2410 { 2411 might_sleep(); 2412 spin_lock_bh(&sk->sk_lock.slock); 2413 2414 if (!sk->sk_lock.owned) 2415 /* 2416 * Note : We must disable BH 2417 */ 2418 return false; 2419 2420 __lock_sock(sk); 2421 sk->sk_lock.owned = 1; 2422 spin_unlock(&sk->sk_lock.slock); 2423 /* 2424 * The sk_lock has mutex_lock() semantics here: 2425 */ 2426 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2427 local_bh_enable(); 2428 return true; 2429 } 2430 EXPORT_SYMBOL(lock_sock_fast); 2431 2432 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2433 { 2434 struct timeval tv; 2435 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2436 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2437 tv = ktime_to_timeval(sk->sk_stamp); 2438 if (tv.tv_sec == -1) 2439 return -ENOENT; 2440 if (tv.tv_sec == 0) { 2441 sk->sk_stamp = ktime_get_real(); 2442 tv = ktime_to_timeval(sk->sk_stamp); 2443 } 2444 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2445 } 2446 EXPORT_SYMBOL(sock_get_timestamp); 2447 2448 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2449 { 2450 struct timespec ts; 2451 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2452 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2453 ts = ktime_to_timespec(sk->sk_stamp); 2454 if (ts.tv_sec == -1) 2455 return -ENOENT; 2456 if (ts.tv_sec == 0) { 2457 sk->sk_stamp = ktime_get_real(); 2458 ts = ktime_to_timespec(sk->sk_stamp); 2459 } 2460 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2461 } 2462 EXPORT_SYMBOL(sock_get_timestampns); 2463 2464 void sock_enable_timestamp(struct sock *sk, int flag) 2465 { 2466 if (!sock_flag(sk, flag)) { 2467 unsigned long previous_flags = sk->sk_flags; 2468 2469 sock_set_flag(sk, flag); 2470 /* 2471 * we just set one of the two flags which require net 2472 * time stamping, but time stamping might have been on 2473 * already because of the other one 2474 */ 2475 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2476 net_enable_timestamp(); 2477 } 2478 } 2479 2480 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2481 int level, int type) 2482 { 2483 struct sock_exterr_skb *serr; 2484 struct sk_buff *skb; 2485 int copied, err; 2486 2487 err = -EAGAIN; 2488 skb = sock_dequeue_err_skb(sk); 2489 if (skb == NULL) 2490 goto out; 2491 2492 copied = skb->len; 2493 if (copied > len) { 2494 msg->msg_flags |= MSG_TRUNC; 2495 copied = len; 2496 } 2497 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2498 if (err) 2499 goto out_free_skb; 2500 2501 sock_recv_timestamp(msg, sk, skb); 2502 2503 serr = SKB_EXT_ERR(skb); 2504 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2505 2506 msg->msg_flags |= MSG_ERRQUEUE; 2507 err = copied; 2508 2509 out_free_skb: 2510 kfree_skb(skb); 2511 out: 2512 return err; 2513 } 2514 EXPORT_SYMBOL(sock_recv_errqueue); 2515 2516 /* 2517 * Get a socket option on an socket. 2518 * 2519 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2520 * asynchronous errors should be reported by getsockopt. We assume 2521 * this means if you specify SO_ERROR (otherwise whats the point of it). 2522 */ 2523 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2524 char __user *optval, int __user *optlen) 2525 { 2526 struct sock *sk = sock->sk; 2527 2528 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2529 } 2530 EXPORT_SYMBOL(sock_common_getsockopt); 2531 2532 #ifdef CONFIG_COMPAT 2533 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2534 char __user *optval, int __user *optlen) 2535 { 2536 struct sock *sk = sock->sk; 2537 2538 if (sk->sk_prot->compat_getsockopt != NULL) 2539 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2540 optval, optlen); 2541 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2542 } 2543 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2544 #endif 2545 2546 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 2547 int flags) 2548 { 2549 struct sock *sk = sock->sk; 2550 int addr_len = 0; 2551 int err; 2552 2553 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 2554 flags & ~MSG_DONTWAIT, &addr_len); 2555 if (err >= 0) 2556 msg->msg_namelen = addr_len; 2557 return err; 2558 } 2559 EXPORT_SYMBOL(sock_common_recvmsg); 2560 2561 /* 2562 * Set socket options on an inet socket. 2563 */ 2564 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2565 char __user *optval, unsigned int optlen) 2566 { 2567 struct sock *sk = sock->sk; 2568 2569 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2570 } 2571 EXPORT_SYMBOL(sock_common_setsockopt); 2572 2573 #ifdef CONFIG_COMPAT 2574 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2575 char __user *optval, unsigned int optlen) 2576 { 2577 struct sock *sk = sock->sk; 2578 2579 if (sk->sk_prot->compat_setsockopt != NULL) 2580 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2581 optval, optlen); 2582 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2583 } 2584 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2585 #endif 2586 2587 void sk_common_release(struct sock *sk) 2588 { 2589 if (sk->sk_prot->destroy) 2590 sk->sk_prot->destroy(sk); 2591 2592 /* 2593 * Observation: when sock_common_release is called, processes have 2594 * no access to socket. But net still has. 2595 * Step one, detach it from networking: 2596 * 2597 * A. Remove from hash tables. 2598 */ 2599 2600 sk->sk_prot->unhash(sk); 2601 2602 /* 2603 * In this point socket cannot receive new packets, but it is possible 2604 * that some packets are in flight because some CPU runs receiver and 2605 * did hash table lookup before we unhashed socket. They will achieve 2606 * receive queue and will be purged by socket destructor. 2607 * 2608 * Also we still have packets pending on receive queue and probably, 2609 * our own packets waiting in device queues. sock_destroy will drain 2610 * receive queue, but transmitted packets will delay socket destruction 2611 * until the last reference will be released. 2612 */ 2613 2614 sock_orphan(sk); 2615 2616 xfrm_sk_free_policy(sk); 2617 2618 sk_refcnt_debug_release(sk); 2619 2620 if (sk->sk_frag.page) { 2621 put_page(sk->sk_frag.page); 2622 sk->sk_frag.page = NULL; 2623 } 2624 2625 sock_put(sk); 2626 } 2627 EXPORT_SYMBOL(sk_common_release); 2628 2629 #ifdef CONFIG_PROC_FS 2630 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2631 struct prot_inuse { 2632 int val[PROTO_INUSE_NR]; 2633 }; 2634 2635 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2636 2637 #ifdef CONFIG_NET_NS 2638 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2639 { 2640 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2641 } 2642 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2643 2644 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2645 { 2646 int cpu, idx = prot->inuse_idx; 2647 int res = 0; 2648 2649 for_each_possible_cpu(cpu) 2650 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2651 2652 return res >= 0 ? res : 0; 2653 } 2654 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2655 2656 static int __net_init sock_inuse_init_net(struct net *net) 2657 { 2658 net->core.inuse = alloc_percpu(struct prot_inuse); 2659 return net->core.inuse ? 0 : -ENOMEM; 2660 } 2661 2662 static void __net_exit sock_inuse_exit_net(struct net *net) 2663 { 2664 free_percpu(net->core.inuse); 2665 } 2666 2667 static struct pernet_operations net_inuse_ops = { 2668 .init = sock_inuse_init_net, 2669 .exit = sock_inuse_exit_net, 2670 }; 2671 2672 static __init int net_inuse_init(void) 2673 { 2674 if (register_pernet_subsys(&net_inuse_ops)) 2675 panic("Cannot initialize net inuse counters"); 2676 2677 return 0; 2678 } 2679 2680 core_initcall(net_inuse_init); 2681 #else 2682 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2683 2684 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2685 { 2686 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2687 } 2688 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2689 2690 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2691 { 2692 int cpu, idx = prot->inuse_idx; 2693 int res = 0; 2694 2695 for_each_possible_cpu(cpu) 2696 res += per_cpu(prot_inuse, cpu).val[idx]; 2697 2698 return res >= 0 ? res : 0; 2699 } 2700 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2701 #endif 2702 2703 static void assign_proto_idx(struct proto *prot) 2704 { 2705 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2706 2707 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2708 pr_err("PROTO_INUSE_NR exhausted\n"); 2709 return; 2710 } 2711 2712 set_bit(prot->inuse_idx, proto_inuse_idx); 2713 } 2714 2715 static void release_proto_idx(struct proto *prot) 2716 { 2717 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2718 clear_bit(prot->inuse_idx, proto_inuse_idx); 2719 } 2720 #else 2721 static inline void assign_proto_idx(struct proto *prot) 2722 { 2723 } 2724 2725 static inline void release_proto_idx(struct proto *prot) 2726 { 2727 } 2728 #endif 2729 2730 int proto_register(struct proto *prot, int alloc_slab) 2731 { 2732 if (alloc_slab) { 2733 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2734 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2735 NULL); 2736 2737 if (prot->slab == NULL) { 2738 pr_crit("%s: Can't create sock SLAB cache!\n", 2739 prot->name); 2740 goto out; 2741 } 2742 2743 if (prot->rsk_prot != NULL) { 2744 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2745 if (prot->rsk_prot->slab_name == NULL) 2746 goto out_free_sock_slab; 2747 2748 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2749 prot->rsk_prot->obj_size, 0, 2750 SLAB_HWCACHE_ALIGN, NULL); 2751 2752 if (prot->rsk_prot->slab == NULL) { 2753 pr_crit("%s: Can't create request sock SLAB cache!\n", 2754 prot->name); 2755 goto out_free_request_sock_slab_name; 2756 } 2757 } 2758 2759 if (prot->twsk_prot != NULL) { 2760 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2761 2762 if (prot->twsk_prot->twsk_slab_name == NULL) 2763 goto out_free_request_sock_slab; 2764 2765 prot->twsk_prot->twsk_slab = 2766 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2767 prot->twsk_prot->twsk_obj_size, 2768 0, 2769 SLAB_HWCACHE_ALIGN | 2770 prot->slab_flags, 2771 NULL); 2772 if (prot->twsk_prot->twsk_slab == NULL) 2773 goto out_free_timewait_sock_slab_name; 2774 } 2775 } 2776 2777 mutex_lock(&proto_list_mutex); 2778 list_add(&prot->node, &proto_list); 2779 assign_proto_idx(prot); 2780 mutex_unlock(&proto_list_mutex); 2781 return 0; 2782 2783 out_free_timewait_sock_slab_name: 2784 kfree(prot->twsk_prot->twsk_slab_name); 2785 out_free_request_sock_slab: 2786 if (prot->rsk_prot && prot->rsk_prot->slab) { 2787 kmem_cache_destroy(prot->rsk_prot->slab); 2788 prot->rsk_prot->slab = NULL; 2789 } 2790 out_free_request_sock_slab_name: 2791 if (prot->rsk_prot) 2792 kfree(prot->rsk_prot->slab_name); 2793 out_free_sock_slab: 2794 kmem_cache_destroy(prot->slab); 2795 prot->slab = NULL; 2796 out: 2797 return -ENOBUFS; 2798 } 2799 EXPORT_SYMBOL(proto_register); 2800 2801 void proto_unregister(struct proto *prot) 2802 { 2803 mutex_lock(&proto_list_mutex); 2804 release_proto_idx(prot); 2805 list_del(&prot->node); 2806 mutex_unlock(&proto_list_mutex); 2807 2808 if (prot->slab != NULL) { 2809 kmem_cache_destroy(prot->slab); 2810 prot->slab = NULL; 2811 } 2812 2813 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2814 kmem_cache_destroy(prot->rsk_prot->slab); 2815 kfree(prot->rsk_prot->slab_name); 2816 prot->rsk_prot->slab = NULL; 2817 } 2818 2819 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2820 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2821 kfree(prot->twsk_prot->twsk_slab_name); 2822 prot->twsk_prot->twsk_slab = NULL; 2823 } 2824 } 2825 EXPORT_SYMBOL(proto_unregister); 2826 2827 #ifdef CONFIG_PROC_FS 2828 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2829 __acquires(proto_list_mutex) 2830 { 2831 mutex_lock(&proto_list_mutex); 2832 return seq_list_start_head(&proto_list, *pos); 2833 } 2834 2835 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2836 { 2837 return seq_list_next(v, &proto_list, pos); 2838 } 2839 2840 static void proto_seq_stop(struct seq_file *seq, void *v) 2841 __releases(proto_list_mutex) 2842 { 2843 mutex_unlock(&proto_list_mutex); 2844 } 2845 2846 static char proto_method_implemented(const void *method) 2847 { 2848 return method == NULL ? 'n' : 'y'; 2849 } 2850 static long sock_prot_memory_allocated(struct proto *proto) 2851 { 2852 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2853 } 2854 2855 static char *sock_prot_memory_pressure(struct proto *proto) 2856 { 2857 return proto->memory_pressure != NULL ? 2858 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2859 } 2860 2861 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2862 { 2863 2864 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2865 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2866 proto->name, 2867 proto->obj_size, 2868 sock_prot_inuse_get(seq_file_net(seq), proto), 2869 sock_prot_memory_allocated(proto), 2870 sock_prot_memory_pressure(proto), 2871 proto->max_header, 2872 proto->slab == NULL ? "no" : "yes", 2873 module_name(proto->owner), 2874 proto_method_implemented(proto->close), 2875 proto_method_implemented(proto->connect), 2876 proto_method_implemented(proto->disconnect), 2877 proto_method_implemented(proto->accept), 2878 proto_method_implemented(proto->ioctl), 2879 proto_method_implemented(proto->init), 2880 proto_method_implemented(proto->destroy), 2881 proto_method_implemented(proto->shutdown), 2882 proto_method_implemented(proto->setsockopt), 2883 proto_method_implemented(proto->getsockopt), 2884 proto_method_implemented(proto->sendmsg), 2885 proto_method_implemented(proto->recvmsg), 2886 proto_method_implemented(proto->sendpage), 2887 proto_method_implemented(proto->bind), 2888 proto_method_implemented(proto->backlog_rcv), 2889 proto_method_implemented(proto->hash), 2890 proto_method_implemented(proto->unhash), 2891 proto_method_implemented(proto->get_port), 2892 proto_method_implemented(proto->enter_memory_pressure)); 2893 } 2894 2895 static int proto_seq_show(struct seq_file *seq, void *v) 2896 { 2897 if (v == &proto_list) 2898 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2899 "protocol", 2900 "size", 2901 "sockets", 2902 "memory", 2903 "press", 2904 "maxhdr", 2905 "slab", 2906 "module", 2907 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2908 else 2909 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2910 return 0; 2911 } 2912 2913 static const struct seq_operations proto_seq_ops = { 2914 .start = proto_seq_start, 2915 .next = proto_seq_next, 2916 .stop = proto_seq_stop, 2917 .show = proto_seq_show, 2918 }; 2919 2920 static int proto_seq_open(struct inode *inode, struct file *file) 2921 { 2922 return seq_open_net(inode, file, &proto_seq_ops, 2923 sizeof(struct seq_net_private)); 2924 } 2925 2926 static const struct file_operations proto_seq_fops = { 2927 .owner = THIS_MODULE, 2928 .open = proto_seq_open, 2929 .read = seq_read, 2930 .llseek = seq_lseek, 2931 .release = seq_release_net, 2932 }; 2933 2934 static __net_init int proto_init_net(struct net *net) 2935 { 2936 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2937 return -ENOMEM; 2938 2939 return 0; 2940 } 2941 2942 static __net_exit void proto_exit_net(struct net *net) 2943 { 2944 remove_proc_entry("protocols", net->proc_net); 2945 } 2946 2947 2948 static __net_initdata struct pernet_operations proto_net_ops = { 2949 .init = proto_init_net, 2950 .exit = proto_exit_net, 2951 }; 2952 2953 static int __init proto_init(void) 2954 { 2955 return register_pernet_subsys(&proto_net_ops); 2956 } 2957 2958 subsys_initcall(proto_init); 2959 2960 #endif /* PROC_FS */ 2961