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 capbility 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 socke 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 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 329 EXPORT_SYMBOL_GPL(memalloc_socks); 330 331 /** 332 * sk_set_memalloc - sets %SOCK_MEMALLOC 333 * @sk: socket to set it on 334 * 335 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 336 * It's the responsibility of the admin to adjust min_free_kbytes 337 * to meet the requirements 338 */ 339 void sk_set_memalloc(struct sock *sk) 340 { 341 sock_set_flag(sk, SOCK_MEMALLOC); 342 sk->sk_allocation |= __GFP_MEMALLOC; 343 static_key_slow_inc(&memalloc_socks); 344 } 345 EXPORT_SYMBOL_GPL(sk_set_memalloc); 346 347 void sk_clear_memalloc(struct sock *sk) 348 { 349 sock_reset_flag(sk, SOCK_MEMALLOC); 350 sk->sk_allocation &= ~__GFP_MEMALLOC; 351 static_key_slow_dec(&memalloc_socks); 352 353 /* 354 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 355 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 356 * it has rmem allocations there is a risk that the user of the 357 * socket cannot make forward progress due to exceeding the rmem 358 * limits. By rights, sk_clear_memalloc() should only be called 359 * on sockets being torn down but warn and reset the accounting if 360 * that assumption breaks. 361 */ 362 if (WARN_ON(sk->sk_forward_alloc)) 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 int skb_len; 441 unsigned long flags; 442 struct sk_buff_head *list = &sk->sk_receive_queue; 443 444 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 445 atomic_inc(&sk->sk_drops); 446 trace_sock_rcvqueue_full(sk, skb); 447 return -ENOMEM; 448 } 449 450 err = sk_filter(sk, skb); 451 if (err) 452 return err; 453 454 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 455 atomic_inc(&sk->sk_drops); 456 return -ENOBUFS; 457 } 458 459 skb->dev = NULL; 460 skb_set_owner_r(skb, sk); 461 462 /* Cache the SKB length before we tack it onto the receive 463 * queue. Once it is added it no longer belongs to us and 464 * may be freed by other threads of control pulling packets 465 * from the queue. 466 */ 467 skb_len = skb->len; 468 469 /* we escape from rcu protected region, make sure we dont leak 470 * a norefcounted dst 471 */ 472 skb_dst_force(skb); 473 474 spin_lock_irqsave(&list->lock, flags); 475 skb->dropcount = atomic_read(&sk->sk_drops); 476 __skb_queue_tail(list, skb); 477 spin_unlock_irqrestore(&list->lock, flags); 478 479 if (!sock_flag(sk, SOCK_DEAD)) 480 sk->sk_data_ready(sk); 481 return 0; 482 } 483 EXPORT_SYMBOL(sock_queue_rcv_skb); 484 485 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 486 { 487 int rc = NET_RX_SUCCESS; 488 489 if (sk_filter(sk, skb)) 490 goto discard_and_relse; 491 492 skb->dev = NULL; 493 494 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 495 atomic_inc(&sk->sk_drops); 496 goto discard_and_relse; 497 } 498 if (nested) 499 bh_lock_sock_nested(sk); 500 else 501 bh_lock_sock(sk); 502 if (!sock_owned_by_user(sk)) { 503 /* 504 * trylock + unlock semantics: 505 */ 506 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 507 508 rc = sk_backlog_rcv(sk, skb); 509 510 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 511 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 512 bh_unlock_sock(sk); 513 atomic_inc(&sk->sk_drops); 514 goto discard_and_relse; 515 } 516 517 bh_unlock_sock(sk); 518 out: 519 sock_put(sk); 520 return rc; 521 discard_and_relse: 522 kfree_skb(skb); 523 goto out; 524 } 525 EXPORT_SYMBOL(sk_receive_skb); 526 527 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 528 { 529 struct dst_entry *dst = __sk_dst_get(sk); 530 531 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 532 sk_tx_queue_clear(sk); 533 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 534 dst_release(dst); 535 return NULL; 536 } 537 538 return dst; 539 } 540 EXPORT_SYMBOL(__sk_dst_check); 541 542 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 543 { 544 struct dst_entry *dst = sk_dst_get(sk); 545 546 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 547 sk_dst_reset(sk); 548 dst_release(dst); 549 return NULL; 550 } 551 552 return dst; 553 } 554 EXPORT_SYMBOL(sk_dst_check); 555 556 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 557 int optlen) 558 { 559 int ret = -ENOPROTOOPT; 560 #ifdef CONFIG_NETDEVICES 561 struct net *net = sock_net(sk); 562 char devname[IFNAMSIZ]; 563 int index; 564 565 /* Sorry... */ 566 ret = -EPERM; 567 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 568 goto out; 569 570 ret = -EINVAL; 571 if (optlen < 0) 572 goto out; 573 574 /* Bind this socket to a particular device like "eth0", 575 * as specified in the passed interface name. If the 576 * name is "" or the option length is zero the socket 577 * is not bound. 578 */ 579 if (optlen > IFNAMSIZ - 1) 580 optlen = IFNAMSIZ - 1; 581 memset(devname, 0, sizeof(devname)); 582 583 ret = -EFAULT; 584 if (copy_from_user(devname, optval, optlen)) 585 goto out; 586 587 index = 0; 588 if (devname[0] != '\0') { 589 struct net_device *dev; 590 591 rcu_read_lock(); 592 dev = dev_get_by_name_rcu(net, devname); 593 if (dev) 594 index = dev->ifindex; 595 rcu_read_unlock(); 596 ret = -ENODEV; 597 if (!dev) 598 goto out; 599 } 600 601 lock_sock(sk); 602 sk->sk_bound_dev_if = index; 603 sk_dst_reset(sk); 604 release_sock(sk); 605 606 ret = 0; 607 608 out: 609 #endif 610 611 return ret; 612 } 613 614 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 615 int __user *optlen, int len) 616 { 617 int ret = -ENOPROTOOPT; 618 #ifdef CONFIG_NETDEVICES 619 struct net *net = sock_net(sk); 620 char devname[IFNAMSIZ]; 621 622 if (sk->sk_bound_dev_if == 0) { 623 len = 0; 624 goto zero; 625 } 626 627 ret = -EINVAL; 628 if (len < IFNAMSIZ) 629 goto out; 630 631 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 632 if (ret) 633 goto out; 634 635 len = strlen(devname) + 1; 636 637 ret = -EFAULT; 638 if (copy_to_user(optval, devname, len)) 639 goto out; 640 641 zero: 642 ret = -EFAULT; 643 if (put_user(len, optlen)) 644 goto out; 645 646 ret = 0; 647 648 out: 649 #endif 650 651 return ret; 652 } 653 654 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 655 { 656 if (valbool) 657 sock_set_flag(sk, bit); 658 else 659 sock_reset_flag(sk, bit); 660 } 661 662 /* 663 * This is meant for all protocols to use and covers goings on 664 * at the socket level. Everything here is generic. 665 */ 666 667 int sock_setsockopt(struct socket *sock, int level, int optname, 668 char __user *optval, unsigned int optlen) 669 { 670 struct sock *sk = sock->sk; 671 int val; 672 int valbool; 673 struct linger ling; 674 int ret = 0; 675 676 /* 677 * Options without arguments 678 */ 679 680 if (optname == SO_BINDTODEVICE) 681 return sock_setbindtodevice(sk, optval, optlen); 682 683 if (optlen < sizeof(int)) 684 return -EINVAL; 685 686 if (get_user(val, (int __user *)optval)) 687 return -EFAULT; 688 689 valbool = val ? 1 : 0; 690 691 lock_sock(sk); 692 693 switch (optname) { 694 case SO_DEBUG: 695 if (val && !capable(CAP_NET_ADMIN)) 696 ret = -EACCES; 697 else 698 sock_valbool_flag(sk, SOCK_DBG, valbool); 699 break; 700 case SO_REUSEADDR: 701 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 702 break; 703 case SO_REUSEPORT: 704 sk->sk_reuseport = valbool; 705 break; 706 case SO_TYPE: 707 case SO_PROTOCOL: 708 case SO_DOMAIN: 709 case SO_ERROR: 710 ret = -ENOPROTOOPT; 711 break; 712 case SO_DONTROUTE: 713 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 714 break; 715 case SO_BROADCAST: 716 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 717 break; 718 case SO_SNDBUF: 719 /* Don't error on this BSD doesn't and if you think 720 * about it this is right. Otherwise apps have to 721 * play 'guess the biggest size' games. RCVBUF/SNDBUF 722 * are treated in BSD as hints 723 */ 724 val = min_t(u32, val, sysctl_wmem_max); 725 set_sndbuf: 726 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 727 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 728 /* Wake up sending tasks if we upped the value. */ 729 sk->sk_write_space(sk); 730 break; 731 732 case SO_SNDBUFFORCE: 733 if (!capable(CAP_NET_ADMIN)) { 734 ret = -EPERM; 735 break; 736 } 737 goto set_sndbuf; 738 739 case SO_RCVBUF: 740 /* Don't error on this BSD doesn't and if you think 741 * about it this is right. Otherwise apps have to 742 * play 'guess the biggest size' games. RCVBUF/SNDBUF 743 * are treated in BSD as hints 744 */ 745 val = min_t(u32, val, sysctl_rmem_max); 746 set_rcvbuf: 747 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 748 /* 749 * We double it on the way in to account for 750 * "struct sk_buff" etc. overhead. Applications 751 * assume that the SO_RCVBUF setting they make will 752 * allow that much actual data to be received on that 753 * socket. 754 * 755 * Applications are unaware that "struct sk_buff" and 756 * other overheads allocate from the receive buffer 757 * during socket buffer allocation. 758 * 759 * And after considering the possible alternatives, 760 * returning the value we actually used in getsockopt 761 * is the most desirable behavior. 762 */ 763 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 764 break; 765 766 case SO_RCVBUFFORCE: 767 if (!capable(CAP_NET_ADMIN)) { 768 ret = -EPERM; 769 break; 770 } 771 goto set_rcvbuf; 772 773 case SO_KEEPALIVE: 774 #ifdef CONFIG_INET 775 if (sk->sk_protocol == IPPROTO_TCP && 776 sk->sk_type == SOCK_STREAM) 777 tcp_set_keepalive(sk, valbool); 778 #endif 779 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 780 break; 781 782 case SO_OOBINLINE: 783 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 784 break; 785 786 case SO_NO_CHECK: 787 sk->sk_no_check_tx = valbool; 788 break; 789 790 case SO_PRIORITY: 791 if ((val >= 0 && val <= 6) || 792 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 793 sk->sk_priority = val; 794 else 795 ret = -EPERM; 796 break; 797 798 case SO_LINGER: 799 if (optlen < sizeof(ling)) { 800 ret = -EINVAL; /* 1003.1g */ 801 break; 802 } 803 if (copy_from_user(&ling, optval, sizeof(ling))) { 804 ret = -EFAULT; 805 break; 806 } 807 if (!ling.l_onoff) 808 sock_reset_flag(sk, SOCK_LINGER); 809 else { 810 #if (BITS_PER_LONG == 32) 811 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 812 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 813 else 814 #endif 815 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 816 sock_set_flag(sk, SOCK_LINGER); 817 } 818 break; 819 820 case SO_BSDCOMPAT: 821 sock_warn_obsolete_bsdism("setsockopt"); 822 break; 823 824 case SO_PASSCRED: 825 if (valbool) 826 set_bit(SOCK_PASSCRED, &sock->flags); 827 else 828 clear_bit(SOCK_PASSCRED, &sock->flags); 829 break; 830 831 case SO_TIMESTAMP: 832 case SO_TIMESTAMPNS: 833 if (valbool) { 834 if (optname == SO_TIMESTAMP) 835 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 836 else 837 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 838 sock_set_flag(sk, SOCK_RCVTSTAMP); 839 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 840 } else { 841 sock_reset_flag(sk, SOCK_RCVTSTAMP); 842 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 843 } 844 break; 845 846 case SO_TIMESTAMPING: 847 if (val & ~SOF_TIMESTAMPING_MASK) { 848 ret = -EINVAL; 849 break; 850 } 851 sk->sk_tsflags = val; 852 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 853 sock_enable_timestamp(sk, 854 SOCK_TIMESTAMPING_RX_SOFTWARE); 855 else 856 sock_disable_timestamp(sk, 857 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 858 break; 859 860 case SO_RCVLOWAT: 861 if (val < 0) 862 val = INT_MAX; 863 sk->sk_rcvlowat = val ? : 1; 864 break; 865 866 case SO_RCVTIMEO: 867 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 868 break; 869 870 case SO_SNDTIMEO: 871 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 872 break; 873 874 case SO_ATTACH_FILTER: 875 ret = -EINVAL; 876 if (optlen == sizeof(struct sock_fprog)) { 877 struct sock_fprog fprog; 878 879 ret = -EFAULT; 880 if (copy_from_user(&fprog, optval, sizeof(fprog))) 881 break; 882 883 ret = sk_attach_filter(&fprog, sk); 884 } 885 break; 886 887 case SO_DETACH_FILTER: 888 ret = sk_detach_filter(sk); 889 break; 890 891 case SO_LOCK_FILTER: 892 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 893 ret = -EPERM; 894 else 895 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 896 break; 897 898 case SO_PASSSEC: 899 if (valbool) 900 set_bit(SOCK_PASSSEC, &sock->flags); 901 else 902 clear_bit(SOCK_PASSSEC, &sock->flags); 903 break; 904 case SO_MARK: 905 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 906 ret = -EPERM; 907 else 908 sk->sk_mark = val; 909 break; 910 911 /* We implement the SO_SNDLOWAT etc to 912 not be settable (1003.1g 5.3) */ 913 case SO_RXQ_OVFL: 914 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 915 break; 916 917 case SO_WIFI_STATUS: 918 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 919 break; 920 921 case SO_PEEK_OFF: 922 if (sock->ops->set_peek_off) 923 ret = sock->ops->set_peek_off(sk, val); 924 else 925 ret = -EOPNOTSUPP; 926 break; 927 928 case SO_NOFCS: 929 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 930 break; 931 932 case SO_SELECT_ERR_QUEUE: 933 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 934 break; 935 936 #ifdef CONFIG_NET_RX_BUSY_POLL 937 case SO_BUSY_POLL: 938 /* allow unprivileged users to decrease the value */ 939 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 940 ret = -EPERM; 941 else { 942 if (val < 0) 943 ret = -EINVAL; 944 else 945 sk->sk_ll_usec = val; 946 } 947 break; 948 #endif 949 950 case SO_MAX_PACING_RATE: 951 sk->sk_max_pacing_rate = val; 952 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 953 sk->sk_max_pacing_rate); 954 break; 955 956 default: 957 ret = -ENOPROTOOPT; 958 break; 959 } 960 release_sock(sk); 961 return ret; 962 } 963 EXPORT_SYMBOL(sock_setsockopt); 964 965 966 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 967 struct ucred *ucred) 968 { 969 ucred->pid = pid_vnr(pid); 970 ucred->uid = ucred->gid = -1; 971 if (cred) { 972 struct user_namespace *current_ns = current_user_ns(); 973 974 ucred->uid = from_kuid_munged(current_ns, cred->euid); 975 ucred->gid = from_kgid_munged(current_ns, cred->egid); 976 } 977 } 978 979 int sock_getsockopt(struct socket *sock, int level, int optname, 980 char __user *optval, int __user *optlen) 981 { 982 struct sock *sk = sock->sk; 983 984 union { 985 int val; 986 struct linger ling; 987 struct timeval tm; 988 } v; 989 990 int lv = sizeof(int); 991 int len; 992 993 if (get_user(len, optlen)) 994 return -EFAULT; 995 if (len < 0) 996 return -EINVAL; 997 998 memset(&v, 0, sizeof(v)); 999 1000 switch (optname) { 1001 case SO_DEBUG: 1002 v.val = sock_flag(sk, SOCK_DBG); 1003 break; 1004 1005 case SO_DONTROUTE: 1006 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1007 break; 1008 1009 case SO_BROADCAST: 1010 v.val = sock_flag(sk, SOCK_BROADCAST); 1011 break; 1012 1013 case SO_SNDBUF: 1014 v.val = sk->sk_sndbuf; 1015 break; 1016 1017 case SO_RCVBUF: 1018 v.val = sk->sk_rcvbuf; 1019 break; 1020 1021 case SO_REUSEADDR: 1022 v.val = sk->sk_reuse; 1023 break; 1024 1025 case SO_REUSEPORT: 1026 v.val = sk->sk_reuseport; 1027 break; 1028 1029 case SO_KEEPALIVE: 1030 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1031 break; 1032 1033 case SO_TYPE: 1034 v.val = sk->sk_type; 1035 break; 1036 1037 case SO_PROTOCOL: 1038 v.val = sk->sk_protocol; 1039 break; 1040 1041 case SO_DOMAIN: 1042 v.val = sk->sk_family; 1043 break; 1044 1045 case SO_ERROR: 1046 v.val = -sock_error(sk); 1047 if (v.val == 0) 1048 v.val = xchg(&sk->sk_err_soft, 0); 1049 break; 1050 1051 case SO_OOBINLINE: 1052 v.val = sock_flag(sk, SOCK_URGINLINE); 1053 break; 1054 1055 case SO_NO_CHECK: 1056 v.val = sk->sk_no_check_tx; 1057 break; 1058 1059 case SO_PRIORITY: 1060 v.val = sk->sk_priority; 1061 break; 1062 1063 case SO_LINGER: 1064 lv = sizeof(v.ling); 1065 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1066 v.ling.l_linger = sk->sk_lingertime / HZ; 1067 break; 1068 1069 case SO_BSDCOMPAT: 1070 sock_warn_obsolete_bsdism("getsockopt"); 1071 break; 1072 1073 case SO_TIMESTAMP: 1074 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1075 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1076 break; 1077 1078 case SO_TIMESTAMPNS: 1079 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1080 break; 1081 1082 case SO_TIMESTAMPING: 1083 v.val = sk->sk_tsflags; 1084 break; 1085 1086 case SO_RCVTIMEO: 1087 lv = sizeof(struct timeval); 1088 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1089 v.tm.tv_sec = 0; 1090 v.tm.tv_usec = 0; 1091 } else { 1092 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1093 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1094 } 1095 break; 1096 1097 case SO_SNDTIMEO: 1098 lv = sizeof(struct timeval); 1099 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1100 v.tm.tv_sec = 0; 1101 v.tm.tv_usec = 0; 1102 } else { 1103 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1104 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1105 } 1106 break; 1107 1108 case SO_RCVLOWAT: 1109 v.val = sk->sk_rcvlowat; 1110 break; 1111 1112 case SO_SNDLOWAT: 1113 v.val = 1; 1114 break; 1115 1116 case SO_PASSCRED: 1117 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1118 break; 1119 1120 case SO_PEERCRED: 1121 { 1122 struct ucred peercred; 1123 if (len > sizeof(peercred)) 1124 len = sizeof(peercred); 1125 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1126 if (copy_to_user(optval, &peercred, len)) 1127 return -EFAULT; 1128 goto lenout; 1129 } 1130 1131 case SO_PEERNAME: 1132 { 1133 char address[128]; 1134 1135 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1136 return -ENOTCONN; 1137 if (lv < len) 1138 return -EINVAL; 1139 if (copy_to_user(optval, address, len)) 1140 return -EFAULT; 1141 goto lenout; 1142 } 1143 1144 /* Dubious BSD thing... Probably nobody even uses it, but 1145 * the UNIX standard wants it for whatever reason... -DaveM 1146 */ 1147 case SO_ACCEPTCONN: 1148 v.val = sk->sk_state == TCP_LISTEN; 1149 break; 1150 1151 case SO_PASSSEC: 1152 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1153 break; 1154 1155 case SO_PEERSEC: 1156 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1157 1158 case SO_MARK: 1159 v.val = sk->sk_mark; 1160 break; 1161 1162 case SO_RXQ_OVFL: 1163 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1164 break; 1165 1166 case SO_WIFI_STATUS: 1167 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1168 break; 1169 1170 case SO_PEEK_OFF: 1171 if (!sock->ops->set_peek_off) 1172 return -EOPNOTSUPP; 1173 1174 v.val = sk->sk_peek_off; 1175 break; 1176 case SO_NOFCS: 1177 v.val = sock_flag(sk, SOCK_NOFCS); 1178 break; 1179 1180 case SO_BINDTODEVICE: 1181 return sock_getbindtodevice(sk, optval, optlen, len); 1182 1183 case SO_GET_FILTER: 1184 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1185 if (len < 0) 1186 return len; 1187 1188 goto lenout; 1189 1190 case SO_LOCK_FILTER: 1191 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1192 break; 1193 1194 case SO_BPF_EXTENSIONS: 1195 v.val = bpf_tell_extensions(); 1196 break; 1197 1198 case SO_SELECT_ERR_QUEUE: 1199 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1200 break; 1201 1202 #ifdef CONFIG_NET_RX_BUSY_POLL 1203 case SO_BUSY_POLL: 1204 v.val = sk->sk_ll_usec; 1205 break; 1206 #endif 1207 1208 case SO_MAX_PACING_RATE: 1209 v.val = sk->sk_max_pacing_rate; 1210 break; 1211 1212 default: 1213 return -ENOPROTOOPT; 1214 } 1215 1216 if (len > lv) 1217 len = lv; 1218 if (copy_to_user(optval, &v, len)) 1219 return -EFAULT; 1220 lenout: 1221 if (put_user(len, optlen)) 1222 return -EFAULT; 1223 return 0; 1224 } 1225 1226 /* 1227 * Initialize an sk_lock. 1228 * 1229 * (We also register the sk_lock with the lock validator.) 1230 */ 1231 static inline void sock_lock_init(struct sock *sk) 1232 { 1233 sock_lock_init_class_and_name(sk, 1234 af_family_slock_key_strings[sk->sk_family], 1235 af_family_slock_keys + sk->sk_family, 1236 af_family_key_strings[sk->sk_family], 1237 af_family_keys + sk->sk_family); 1238 } 1239 1240 /* 1241 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1242 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1243 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1244 */ 1245 static void sock_copy(struct sock *nsk, const struct sock *osk) 1246 { 1247 #ifdef CONFIG_SECURITY_NETWORK 1248 void *sptr = nsk->sk_security; 1249 #endif 1250 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1251 1252 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1253 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1254 1255 #ifdef CONFIG_SECURITY_NETWORK 1256 nsk->sk_security = sptr; 1257 security_sk_clone(osk, nsk); 1258 #endif 1259 } 1260 1261 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1262 { 1263 unsigned long nulls1, nulls2; 1264 1265 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1266 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1267 if (nulls1 > nulls2) 1268 swap(nulls1, nulls2); 1269 1270 if (nulls1 != 0) 1271 memset((char *)sk, 0, nulls1); 1272 memset((char *)sk + nulls1 + sizeof(void *), 0, 1273 nulls2 - nulls1 - sizeof(void *)); 1274 memset((char *)sk + nulls2 + sizeof(void *), 0, 1275 size - nulls2 - sizeof(void *)); 1276 } 1277 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1278 1279 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1280 int family) 1281 { 1282 struct sock *sk; 1283 struct kmem_cache *slab; 1284 1285 slab = prot->slab; 1286 if (slab != NULL) { 1287 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1288 if (!sk) 1289 return sk; 1290 if (priority & __GFP_ZERO) { 1291 if (prot->clear_sk) 1292 prot->clear_sk(sk, prot->obj_size); 1293 else 1294 sk_prot_clear_nulls(sk, prot->obj_size); 1295 } 1296 } else 1297 sk = kmalloc(prot->obj_size, priority); 1298 1299 if (sk != NULL) { 1300 kmemcheck_annotate_bitfield(sk, flags); 1301 1302 if (security_sk_alloc(sk, family, priority)) 1303 goto out_free; 1304 1305 if (!try_module_get(prot->owner)) 1306 goto out_free_sec; 1307 sk_tx_queue_clear(sk); 1308 } 1309 1310 return sk; 1311 1312 out_free_sec: 1313 security_sk_free(sk); 1314 out_free: 1315 if (slab != NULL) 1316 kmem_cache_free(slab, sk); 1317 else 1318 kfree(sk); 1319 return NULL; 1320 } 1321 1322 static void sk_prot_free(struct proto *prot, struct sock *sk) 1323 { 1324 struct kmem_cache *slab; 1325 struct module *owner; 1326 1327 owner = prot->owner; 1328 slab = prot->slab; 1329 1330 security_sk_free(sk); 1331 if (slab != NULL) 1332 kmem_cache_free(slab, sk); 1333 else 1334 kfree(sk); 1335 module_put(owner); 1336 } 1337 1338 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 1339 void sock_update_netprioidx(struct sock *sk) 1340 { 1341 if (in_interrupt()) 1342 return; 1343 1344 sk->sk_cgrp_prioidx = task_netprioidx(current); 1345 } 1346 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1347 #endif 1348 1349 /** 1350 * sk_alloc - All socket objects are allocated here 1351 * @net: the applicable net namespace 1352 * @family: protocol family 1353 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1354 * @prot: struct proto associated with this new sock instance 1355 */ 1356 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1357 struct proto *prot) 1358 { 1359 struct sock *sk; 1360 1361 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1362 if (sk) { 1363 sk->sk_family = family; 1364 /* 1365 * See comment in struct sock definition to understand 1366 * why we need sk_prot_creator -acme 1367 */ 1368 sk->sk_prot = sk->sk_prot_creator = prot; 1369 sock_lock_init(sk); 1370 sock_net_set(sk, get_net(net)); 1371 atomic_set(&sk->sk_wmem_alloc, 1); 1372 1373 sock_update_classid(sk); 1374 sock_update_netprioidx(sk); 1375 } 1376 1377 return sk; 1378 } 1379 EXPORT_SYMBOL(sk_alloc); 1380 1381 static void __sk_free(struct sock *sk) 1382 { 1383 struct sk_filter *filter; 1384 1385 if (sk->sk_destruct) 1386 sk->sk_destruct(sk); 1387 1388 filter = rcu_dereference_check(sk->sk_filter, 1389 atomic_read(&sk->sk_wmem_alloc) == 0); 1390 if (filter) { 1391 sk_filter_uncharge(sk, filter); 1392 RCU_INIT_POINTER(sk->sk_filter, NULL); 1393 } 1394 1395 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1396 1397 if (atomic_read(&sk->sk_omem_alloc)) 1398 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1399 __func__, atomic_read(&sk->sk_omem_alloc)); 1400 1401 if (sk->sk_peer_cred) 1402 put_cred(sk->sk_peer_cred); 1403 put_pid(sk->sk_peer_pid); 1404 put_net(sock_net(sk)); 1405 sk_prot_free(sk->sk_prot_creator, sk); 1406 } 1407 1408 void sk_free(struct sock *sk) 1409 { 1410 /* 1411 * We subtract one from sk_wmem_alloc and can know if 1412 * some packets are still in some tx queue. 1413 * If not null, sock_wfree() will call __sk_free(sk) later 1414 */ 1415 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1416 __sk_free(sk); 1417 } 1418 EXPORT_SYMBOL(sk_free); 1419 1420 /* 1421 * Last sock_put should drop reference to sk->sk_net. It has already 1422 * been dropped in sk_change_net. Taking reference to stopping namespace 1423 * is not an option. 1424 * Take reference to a socket to remove it from hash _alive_ and after that 1425 * destroy it in the context of init_net. 1426 */ 1427 void sk_release_kernel(struct sock *sk) 1428 { 1429 if (sk == NULL || sk->sk_socket == NULL) 1430 return; 1431 1432 sock_hold(sk); 1433 sock_release(sk->sk_socket); 1434 release_net(sock_net(sk)); 1435 sock_net_set(sk, get_net(&init_net)); 1436 sock_put(sk); 1437 } 1438 EXPORT_SYMBOL(sk_release_kernel); 1439 1440 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1441 { 1442 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1443 sock_update_memcg(newsk); 1444 } 1445 1446 /** 1447 * sk_clone_lock - clone a socket, and lock its clone 1448 * @sk: the socket to clone 1449 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1450 * 1451 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1452 */ 1453 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1454 { 1455 struct sock *newsk; 1456 bool is_charged = true; 1457 1458 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1459 if (newsk != NULL) { 1460 struct sk_filter *filter; 1461 1462 sock_copy(newsk, sk); 1463 1464 /* SANITY */ 1465 get_net(sock_net(newsk)); 1466 sk_node_init(&newsk->sk_node); 1467 sock_lock_init(newsk); 1468 bh_lock_sock(newsk); 1469 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1470 newsk->sk_backlog.len = 0; 1471 1472 atomic_set(&newsk->sk_rmem_alloc, 0); 1473 /* 1474 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1475 */ 1476 atomic_set(&newsk->sk_wmem_alloc, 1); 1477 atomic_set(&newsk->sk_omem_alloc, 0); 1478 skb_queue_head_init(&newsk->sk_receive_queue); 1479 skb_queue_head_init(&newsk->sk_write_queue); 1480 #ifdef CONFIG_NET_DMA 1481 skb_queue_head_init(&newsk->sk_async_wait_queue); 1482 #endif 1483 1484 spin_lock_init(&newsk->sk_dst_lock); 1485 rwlock_init(&newsk->sk_callback_lock); 1486 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1487 af_callback_keys + newsk->sk_family, 1488 af_family_clock_key_strings[newsk->sk_family]); 1489 1490 newsk->sk_dst_cache = NULL; 1491 newsk->sk_wmem_queued = 0; 1492 newsk->sk_forward_alloc = 0; 1493 newsk->sk_send_head = NULL; 1494 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1495 1496 sock_reset_flag(newsk, SOCK_DONE); 1497 skb_queue_head_init(&newsk->sk_error_queue); 1498 1499 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1500 if (filter != NULL) 1501 /* though it's an empty new sock, the charging may fail 1502 * if sysctl_optmem_max was changed between creation of 1503 * original socket and cloning 1504 */ 1505 is_charged = sk_filter_charge(newsk, filter); 1506 1507 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) { 1508 /* It is still raw copy of parent, so invalidate 1509 * destructor and make plain sk_free() */ 1510 newsk->sk_destruct = NULL; 1511 bh_unlock_sock(newsk); 1512 sk_free(newsk); 1513 newsk = NULL; 1514 goto out; 1515 } 1516 1517 newsk->sk_err = 0; 1518 newsk->sk_priority = 0; 1519 /* 1520 * Before updating sk_refcnt, we must commit prior changes to memory 1521 * (Documentation/RCU/rculist_nulls.txt for details) 1522 */ 1523 smp_wmb(); 1524 atomic_set(&newsk->sk_refcnt, 2); 1525 1526 /* 1527 * Increment the counter in the same struct proto as the master 1528 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1529 * is the same as sk->sk_prot->socks, as this field was copied 1530 * with memcpy). 1531 * 1532 * This _changes_ the previous behaviour, where 1533 * tcp_create_openreq_child always was incrementing the 1534 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1535 * to be taken into account in all callers. -acme 1536 */ 1537 sk_refcnt_debug_inc(newsk); 1538 sk_set_socket(newsk, NULL); 1539 newsk->sk_wq = NULL; 1540 1541 sk_update_clone(sk, newsk); 1542 1543 if (newsk->sk_prot->sockets_allocated) 1544 sk_sockets_allocated_inc(newsk); 1545 1546 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1547 net_enable_timestamp(); 1548 } 1549 out: 1550 return newsk; 1551 } 1552 EXPORT_SYMBOL_GPL(sk_clone_lock); 1553 1554 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1555 { 1556 __sk_dst_set(sk, dst); 1557 sk->sk_route_caps = dst->dev->features; 1558 if (sk->sk_route_caps & NETIF_F_GSO) 1559 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1560 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1561 if (sk_can_gso(sk)) { 1562 if (dst->header_len) { 1563 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1564 } else { 1565 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1566 sk->sk_gso_max_size = dst->dev->gso_max_size; 1567 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1568 } 1569 } 1570 } 1571 EXPORT_SYMBOL_GPL(sk_setup_caps); 1572 1573 /* 1574 * Simple resource managers for sockets. 1575 */ 1576 1577 1578 /* 1579 * Write buffer destructor automatically called from kfree_skb. 1580 */ 1581 void sock_wfree(struct sk_buff *skb) 1582 { 1583 struct sock *sk = skb->sk; 1584 unsigned int len = skb->truesize; 1585 1586 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1587 /* 1588 * Keep a reference on sk_wmem_alloc, this will be released 1589 * after sk_write_space() call 1590 */ 1591 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1592 sk->sk_write_space(sk); 1593 len = 1; 1594 } 1595 /* 1596 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1597 * could not do because of in-flight packets 1598 */ 1599 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1600 __sk_free(sk); 1601 } 1602 EXPORT_SYMBOL(sock_wfree); 1603 1604 void skb_orphan_partial(struct sk_buff *skb) 1605 { 1606 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1607 * so we do not completely orphan skb, but transfert all 1608 * accounted bytes but one, to avoid unexpected reorders. 1609 */ 1610 if (skb->destructor == sock_wfree 1611 #ifdef CONFIG_INET 1612 || skb->destructor == tcp_wfree 1613 #endif 1614 ) { 1615 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1616 skb->truesize = 1; 1617 } else { 1618 skb_orphan(skb); 1619 } 1620 } 1621 EXPORT_SYMBOL(skb_orphan_partial); 1622 1623 /* 1624 * Read buffer destructor automatically called from kfree_skb. 1625 */ 1626 void sock_rfree(struct sk_buff *skb) 1627 { 1628 struct sock *sk = skb->sk; 1629 unsigned int len = skb->truesize; 1630 1631 atomic_sub(len, &sk->sk_rmem_alloc); 1632 sk_mem_uncharge(sk, len); 1633 } 1634 EXPORT_SYMBOL(sock_rfree); 1635 1636 void sock_edemux(struct sk_buff *skb) 1637 { 1638 struct sock *sk = skb->sk; 1639 1640 #ifdef CONFIG_INET 1641 if (sk->sk_state == TCP_TIME_WAIT) 1642 inet_twsk_put(inet_twsk(sk)); 1643 else 1644 #endif 1645 sock_put(sk); 1646 } 1647 EXPORT_SYMBOL(sock_edemux); 1648 1649 kuid_t sock_i_uid(struct sock *sk) 1650 { 1651 kuid_t uid; 1652 1653 read_lock_bh(&sk->sk_callback_lock); 1654 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1655 read_unlock_bh(&sk->sk_callback_lock); 1656 return uid; 1657 } 1658 EXPORT_SYMBOL(sock_i_uid); 1659 1660 unsigned long sock_i_ino(struct sock *sk) 1661 { 1662 unsigned long ino; 1663 1664 read_lock_bh(&sk->sk_callback_lock); 1665 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1666 read_unlock_bh(&sk->sk_callback_lock); 1667 return ino; 1668 } 1669 EXPORT_SYMBOL(sock_i_ino); 1670 1671 /* 1672 * Allocate a skb from the socket's send buffer. 1673 */ 1674 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1675 gfp_t priority) 1676 { 1677 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1678 struct sk_buff *skb = alloc_skb(size, priority); 1679 if (skb) { 1680 skb_set_owner_w(skb, sk); 1681 return skb; 1682 } 1683 } 1684 return NULL; 1685 } 1686 EXPORT_SYMBOL(sock_wmalloc); 1687 1688 /* 1689 * Allocate a memory block from the socket's option memory buffer. 1690 */ 1691 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1692 { 1693 if ((unsigned int)size <= sysctl_optmem_max && 1694 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1695 void *mem; 1696 /* First do the add, to avoid the race if kmalloc 1697 * might sleep. 1698 */ 1699 atomic_add(size, &sk->sk_omem_alloc); 1700 mem = kmalloc(size, priority); 1701 if (mem) 1702 return mem; 1703 atomic_sub(size, &sk->sk_omem_alloc); 1704 } 1705 return NULL; 1706 } 1707 EXPORT_SYMBOL(sock_kmalloc); 1708 1709 /* 1710 * Free an option memory block. 1711 */ 1712 void sock_kfree_s(struct sock *sk, void *mem, int size) 1713 { 1714 kfree(mem); 1715 atomic_sub(size, &sk->sk_omem_alloc); 1716 } 1717 EXPORT_SYMBOL(sock_kfree_s); 1718 1719 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1720 I think, these locks should be removed for datagram sockets. 1721 */ 1722 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1723 { 1724 DEFINE_WAIT(wait); 1725 1726 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1727 for (;;) { 1728 if (!timeo) 1729 break; 1730 if (signal_pending(current)) 1731 break; 1732 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1733 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1734 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1735 break; 1736 if (sk->sk_shutdown & SEND_SHUTDOWN) 1737 break; 1738 if (sk->sk_err) 1739 break; 1740 timeo = schedule_timeout(timeo); 1741 } 1742 finish_wait(sk_sleep(sk), &wait); 1743 return timeo; 1744 } 1745 1746 1747 /* 1748 * Generic send/receive buffer handlers 1749 */ 1750 1751 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1752 unsigned long data_len, int noblock, 1753 int *errcode, int max_page_order) 1754 { 1755 struct sk_buff *skb = NULL; 1756 unsigned long chunk; 1757 gfp_t gfp_mask; 1758 long timeo; 1759 int err; 1760 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1761 struct page *page; 1762 int i; 1763 1764 err = -EMSGSIZE; 1765 if (npages > MAX_SKB_FRAGS) 1766 goto failure; 1767 1768 timeo = sock_sndtimeo(sk, noblock); 1769 while (!skb) { 1770 err = sock_error(sk); 1771 if (err != 0) 1772 goto failure; 1773 1774 err = -EPIPE; 1775 if (sk->sk_shutdown & SEND_SHUTDOWN) 1776 goto failure; 1777 1778 if (atomic_read(&sk->sk_wmem_alloc) >= sk->sk_sndbuf) { 1779 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1780 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1781 err = -EAGAIN; 1782 if (!timeo) 1783 goto failure; 1784 if (signal_pending(current)) 1785 goto interrupted; 1786 timeo = sock_wait_for_wmem(sk, timeo); 1787 continue; 1788 } 1789 1790 err = -ENOBUFS; 1791 gfp_mask = sk->sk_allocation; 1792 if (gfp_mask & __GFP_WAIT) 1793 gfp_mask |= __GFP_REPEAT; 1794 1795 skb = alloc_skb(header_len, gfp_mask); 1796 if (!skb) 1797 goto failure; 1798 1799 skb->truesize += data_len; 1800 1801 for (i = 0; npages > 0; i++) { 1802 int order = max_page_order; 1803 1804 while (order) { 1805 if (npages >= 1 << order) { 1806 page = alloc_pages(sk->sk_allocation | 1807 __GFP_COMP | 1808 __GFP_NOWARN | 1809 __GFP_NORETRY, 1810 order); 1811 if (page) 1812 goto fill_page; 1813 } 1814 order--; 1815 } 1816 page = alloc_page(sk->sk_allocation); 1817 if (!page) 1818 goto failure; 1819 fill_page: 1820 chunk = min_t(unsigned long, data_len, 1821 PAGE_SIZE << order); 1822 skb_fill_page_desc(skb, i, page, 0, chunk); 1823 data_len -= chunk; 1824 npages -= 1 << order; 1825 } 1826 } 1827 1828 skb_set_owner_w(skb, sk); 1829 return skb; 1830 1831 interrupted: 1832 err = sock_intr_errno(timeo); 1833 failure: 1834 kfree_skb(skb); 1835 *errcode = err; 1836 return NULL; 1837 } 1838 EXPORT_SYMBOL(sock_alloc_send_pskb); 1839 1840 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1841 int noblock, int *errcode) 1842 { 1843 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1844 } 1845 EXPORT_SYMBOL(sock_alloc_send_skb); 1846 1847 /* On 32bit arches, an skb frag is limited to 2^15 */ 1848 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1849 1850 /** 1851 * skb_page_frag_refill - check that a page_frag contains enough room 1852 * @sz: minimum size of the fragment we want to get 1853 * @pfrag: pointer to page_frag 1854 * @prio: priority for memory allocation 1855 * 1856 * Note: While this allocator tries to use high order pages, there is 1857 * no guarantee that allocations succeed. Therefore, @sz MUST be 1858 * less or equal than PAGE_SIZE. 1859 */ 1860 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio) 1861 { 1862 int order; 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 order = SKB_FRAG_PAGE_ORDER; 1875 do { 1876 gfp_t gfp = prio; 1877 1878 if (order) 1879 gfp |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY; 1880 pfrag->page = alloc_pages(gfp, order); 1881 if (likely(pfrag->page)) { 1882 pfrag->offset = 0; 1883 pfrag->size = PAGE_SIZE << order; 1884 return true; 1885 } 1886 } while (--order >= 0); 1887 1888 return false; 1889 } 1890 EXPORT_SYMBOL(skb_page_frag_refill); 1891 1892 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1893 { 1894 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1895 return true; 1896 1897 sk_enter_memory_pressure(sk); 1898 sk_stream_moderate_sndbuf(sk); 1899 return false; 1900 } 1901 EXPORT_SYMBOL(sk_page_frag_refill); 1902 1903 static void __lock_sock(struct sock *sk) 1904 __releases(&sk->sk_lock.slock) 1905 __acquires(&sk->sk_lock.slock) 1906 { 1907 DEFINE_WAIT(wait); 1908 1909 for (;;) { 1910 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1911 TASK_UNINTERRUPTIBLE); 1912 spin_unlock_bh(&sk->sk_lock.slock); 1913 schedule(); 1914 spin_lock_bh(&sk->sk_lock.slock); 1915 if (!sock_owned_by_user(sk)) 1916 break; 1917 } 1918 finish_wait(&sk->sk_lock.wq, &wait); 1919 } 1920 1921 static void __release_sock(struct sock *sk) 1922 __releases(&sk->sk_lock.slock) 1923 __acquires(&sk->sk_lock.slock) 1924 { 1925 struct sk_buff *skb = sk->sk_backlog.head; 1926 1927 do { 1928 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1929 bh_unlock_sock(sk); 1930 1931 do { 1932 struct sk_buff *next = skb->next; 1933 1934 prefetch(next); 1935 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1936 skb->next = NULL; 1937 sk_backlog_rcv(sk, skb); 1938 1939 /* 1940 * We are in process context here with softirqs 1941 * disabled, use cond_resched_softirq() to preempt. 1942 * This is safe to do because we've taken the backlog 1943 * queue private: 1944 */ 1945 cond_resched_softirq(); 1946 1947 skb = next; 1948 } while (skb != NULL); 1949 1950 bh_lock_sock(sk); 1951 } while ((skb = sk->sk_backlog.head) != NULL); 1952 1953 /* 1954 * Doing the zeroing here guarantee we can not loop forever 1955 * while a wild producer attempts to flood us. 1956 */ 1957 sk->sk_backlog.len = 0; 1958 } 1959 1960 /** 1961 * sk_wait_data - wait for data to arrive at sk_receive_queue 1962 * @sk: sock to wait on 1963 * @timeo: for how long 1964 * 1965 * Now socket state including sk->sk_err is changed only under lock, 1966 * hence we may omit checks after joining wait queue. 1967 * We check receive queue before schedule() only as optimization; 1968 * it is very likely that release_sock() added new data. 1969 */ 1970 int sk_wait_data(struct sock *sk, long *timeo) 1971 { 1972 int rc; 1973 DEFINE_WAIT(wait); 1974 1975 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1976 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1977 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1978 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1979 finish_wait(sk_sleep(sk), &wait); 1980 return rc; 1981 } 1982 EXPORT_SYMBOL(sk_wait_data); 1983 1984 /** 1985 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1986 * @sk: socket 1987 * @size: memory size to allocate 1988 * @kind: allocation type 1989 * 1990 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1991 * rmem allocation. This function assumes that protocols which have 1992 * memory_pressure use sk_wmem_queued as write buffer accounting. 1993 */ 1994 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1995 { 1996 struct proto *prot = sk->sk_prot; 1997 int amt = sk_mem_pages(size); 1998 long allocated; 1999 int parent_status = UNDER_LIMIT; 2000 2001 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 2002 2003 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 2004 2005 /* Under limit. */ 2006 if (parent_status == UNDER_LIMIT && 2007 allocated <= sk_prot_mem_limits(sk, 0)) { 2008 sk_leave_memory_pressure(sk); 2009 return 1; 2010 } 2011 2012 /* Under pressure. (we or our parents) */ 2013 if ((parent_status > SOFT_LIMIT) || 2014 allocated > sk_prot_mem_limits(sk, 1)) 2015 sk_enter_memory_pressure(sk); 2016 2017 /* Over hard limit (we or our parents) */ 2018 if ((parent_status == OVER_LIMIT) || 2019 (allocated > sk_prot_mem_limits(sk, 2))) 2020 goto suppress_allocation; 2021 2022 /* guarantee minimum buffer size under pressure */ 2023 if (kind == SK_MEM_RECV) { 2024 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2025 return 1; 2026 2027 } else { /* SK_MEM_SEND */ 2028 if (sk->sk_type == SOCK_STREAM) { 2029 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2030 return 1; 2031 } else if (atomic_read(&sk->sk_wmem_alloc) < 2032 prot->sysctl_wmem[0]) 2033 return 1; 2034 } 2035 2036 if (sk_has_memory_pressure(sk)) { 2037 int alloc; 2038 2039 if (!sk_under_memory_pressure(sk)) 2040 return 1; 2041 alloc = sk_sockets_allocated_read_positive(sk); 2042 if (sk_prot_mem_limits(sk, 2) > alloc * 2043 sk_mem_pages(sk->sk_wmem_queued + 2044 atomic_read(&sk->sk_rmem_alloc) + 2045 sk->sk_forward_alloc)) 2046 return 1; 2047 } 2048 2049 suppress_allocation: 2050 2051 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2052 sk_stream_moderate_sndbuf(sk); 2053 2054 /* Fail only if socket is _under_ its sndbuf. 2055 * In this case we cannot block, so that we have to fail. 2056 */ 2057 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2058 return 1; 2059 } 2060 2061 trace_sock_exceed_buf_limit(sk, prot, allocated); 2062 2063 /* Alas. Undo changes. */ 2064 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2065 2066 sk_memory_allocated_sub(sk, amt); 2067 2068 return 0; 2069 } 2070 EXPORT_SYMBOL(__sk_mem_schedule); 2071 2072 /** 2073 * __sk_reclaim - reclaim memory_allocated 2074 * @sk: socket 2075 */ 2076 void __sk_mem_reclaim(struct sock *sk) 2077 { 2078 sk_memory_allocated_sub(sk, 2079 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2080 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2081 2082 if (sk_under_memory_pressure(sk) && 2083 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2084 sk_leave_memory_pressure(sk); 2085 } 2086 EXPORT_SYMBOL(__sk_mem_reclaim); 2087 2088 2089 /* 2090 * Set of default routines for initialising struct proto_ops when 2091 * the protocol does not support a particular function. In certain 2092 * cases where it makes no sense for a protocol to have a "do nothing" 2093 * function, some default processing is provided. 2094 */ 2095 2096 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2097 { 2098 return -EOPNOTSUPP; 2099 } 2100 EXPORT_SYMBOL(sock_no_bind); 2101 2102 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2103 int len, int flags) 2104 { 2105 return -EOPNOTSUPP; 2106 } 2107 EXPORT_SYMBOL(sock_no_connect); 2108 2109 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2110 { 2111 return -EOPNOTSUPP; 2112 } 2113 EXPORT_SYMBOL(sock_no_socketpair); 2114 2115 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2116 { 2117 return -EOPNOTSUPP; 2118 } 2119 EXPORT_SYMBOL(sock_no_accept); 2120 2121 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2122 int *len, int peer) 2123 { 2124 return -EOPNOTSUPP; 2125 } 2126 EXPORT_SYMBOL(sock_no_getname); 2127 2128 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2129 { 2130 return 0; 2131 } 2132 EXPORT_SYMBOL(sock_no_poll); 2133 2134 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2135 { 2136 return -EOPNOTSUPP; 2137 } 2138 EXPORT_SYMBOL(sock_no_ioctl); 2139 2140 int sock_no_listen(struct socket *sock, int backlog) 2141 { 2142 return -EOPNOTSUPP; 2143 } 2144 EXPORT_SYMBOL(sock_no_listen); 2145 2146 int sock_no_shutdown(struct socket *sock, int how) 2147 { 2148 return -EOPNOTSUPP; 2149 } 2150 EXPORT_SYMBOL(sock_no_shutdown); 2151 2152 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2153 char __user *optval, unsigned int optlen) 2154 { 2155 return -EOPNOTSUPP; 2156 } 2157 EXPORT_SYMBOL(sock_no_setsockopt); 2158 2159 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2160 char __user *optval, int __user *optlen) 2161 { 2162 return -EOPNOTSUPP; 2163 } 2164 EXPORT_SYMBOL(sock_no_getsockopt); 2165 2166 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2167 size_t len) 2168 { 2169 return -EOPNOTSUPP; 2170 } 2171 EXPORT_SYMBOL(sock_no_sendmsg); 2172 2173 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2174 size_t len, 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 #ifdef CONFIG_NET_DMA 2298 skb_queue_head_init(&sk->sk_async_wait_queue); 2299 #endif 2300 2301 sk->sk_send_head = NULL; 2302 2303 init_timer(&sk->sk_timer); 2304 2305 sk->sk_allocation = GFP_KERNEL; 2306 sk->sk_rcvbuf = sysctl_rmem_default; 2307 sk->sk_sndbuf = sysctl_wmem_default; 2308 sk->sk_state = TCP_CLOSE; 2309 sk_set_socket(sk, sock); 2310 2311 sock_set_flag(sk, SOCK_ZAPPED); 2312 2313 if (sock) { 2314 sk->sk_type = sock->type; 2315 sk->sk_wq = sock->wq; 2316 sock->sk = sk; 2317 } else 2318 sk->sk_wq = NULL; 2319 2320 spin_lock_init(&sk->sk_dst_lock); 2321 rwlock_init(&sk->sk_callback_lock); 2322 lockdep_set_class_and_name(&sk->sk_callback_lock, 2323 af_callback_keys + sk->sk_family, 2324 af_family_clock_key_strings[sk->sk_family]); 2325 2326 sk->sk_state_change = sock_def_wakeup; 2327 sk->sk_data_ready = sock_def_readable; 2328 sk->sk_write_space = sock_def_write_space; 2329 sk->sk_error_report = sock_def_error_report; 2330 sk->sk_destruct = sock_def_destruct; 2331 2332 sk->sk_frag.page = NULL; 2333 sk->sk_frag.offset = 0; 2334 sk->sk_peek_off = -1; 2335 2336 sk->sk_peer_pid = NULL; 2337 sk->sk_peer_cred = NULL; 2338 sk->sk_write_pending = 0; 2339 sk->sk_rcvlowat = 1; 2340 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2341 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2342 2343 sk->sk_stamp = ktime_set(-1L, 0); 2344 2345 #ifdef CONFIG_NET_RX_BUSY_POLL 2346 sk->sk_napi_id = 0; 2347 sk->sk_ll_usec = sysctl_net_busy_read; 2348 #endif 2349 2350 sk->sk_max_pacing_rate = ~0U; 2351 sk->sk_pacing_rate = ~0U; 2352 /* 2353 * Before updating sk_refcnt, we must commit prior changes to memory 2354 * (Documentation/RCU/rculist_nulls.txt for details) 2355 */ 2356 smp_wmb(); 2357 atomic_set(&sk->sk_refcnt, 1); 2358 atomic_set(&sk->sk_drops, 0); 2359 } 2360 EXPORT_SYMBOL(sock_init_data); 2361 2362 void lock_sock_nested(struct sock *sk, int subclass) 2363 { 2364 might_sleep(); 2365 spin_lock_bh(&sk->sk_lock.slock); 2366 if (sk->sk_lock.owned) 2367 __lock_sock(sk); 2368 sk->sk_lock.owned = 1; 2369 spin_unlock(&sk->sk_lock.slock); 2370 /* 2371 * The sk_lock has mutex_lock() semantics here: 2372 */ 2373 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2374 local_bh_enable(); 2375 } 2376 EXPORT_SYMBOL(lock_sock_nested); 2377 2378 void release_sock(struct sock *sk) 2379 { 2380 /* 2381 * The sk_lock has mutex_unlock() semantics: 2382 */ 2383 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2384 2385 spin_lock_bh(&sk->sk_lock.slock); 2386 if (sk->sk_backlog.tail) 2387 __release_sock(sk); 2388 2389 /* Warning : release_cb() might need to release sk ownership, 2390 * ie call sock_release_ownership(sk) before us. 2391 */ 2392 if (sk->sk_prot->release_cb) 2393 sk->sk_prot->release_cb(sk); 2394 2395 sock_release_ownership(sk); 2396 if (waitqueue_active(&sk->sk_lock.wq)) 2397 wake_up(&sk->sk_lock.wq); 2398 spin_unlock_bh(&sk->sk_lock.slock); 2399 } 2400 EXPORT_SYMBOL(release_sock); 2401 2402 /** 2403 * lock_sock_fast - fast version of lock_sock 2404 * @sk: socket 2405 * 2406 * This version should be used for very small section, where process wont block 2407 * return false if fast path is taken 2408 * sk_lock.slock locked, owned = 0, BH disabled 2409 * return true if slow path is taken 2410 * sk_lock.slock unlocked, owned = 1, BH enabled 2411 */ 2412 bool lock_sock_fast(struct sock *sk) 2413 { 2414 might_sleep(); 2415 spin_lock_bh(&sk->sk_lock.slock); 2416 2417 if (!sk->sk_lock.owned) 2418 /* 2419 * Note : We must disable BH 2420 */ 2421 return false; 2422 2423 __lock_sock(sk); 2424 sk->sk_lock.owned = 1; 2425 spin_unlock(&sk->sk_lock.slock); 2426 /* 2427 * The sk_lock has mutex_lock() semantics here: 2428 */ 2429 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2430 local_bh_enable(); 2431 return true; 2432 } 2433 EXPORT_SYMBOL(lock_sock_fast); 2434 2435 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2436 { 2437 struct timeval tv; 2438 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2439 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2440 tv = ktime_to_timeval(sk->sk_stamp); 2441 if (tv.tv_sec == -1) 2442 return -ENOENT; 2443 if (tv.tv_sec == 0) { 2444 sk->sk_stamp = ktime_get_real(); 2445 tv = ktime_to_timeval(sk->sk_stamp); 2446 } 2447 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2448 } 2449 EXPORT_SYMBOL(sock_get_timestamp); 2450 2451 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2452 { 2453 struct timespec ts; 2454 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2455 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2456 ts = ktime_to_timespec(sk->sk_stamp); 2457 if (ts.tv_sec == -1) 2458 return -ENOENT; 2459 if (ts.tv_sec == 0) { 2460 sk->sk_stamp = ktime_get_real(); 2461 ts = ktime_to_timespec(sk->sk_stamp); 2462 } 2463 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2464 } 2465 EXPORT_SYMBOL(sock_get_timestampns); 2466 2467 void sock_enable_timestamp(struct sock *sk, int flag) 2468 { 2469 if (!sock_flag(sk, flag)) { 2470 unsigned long previous_flags = sk->sk_flags; 2471 2472 sock_set_flag(sk, flag); 2473 /* 2474 * we just set one of the two flags which require net 2475 * time stamping, but time stamping might have been on 2476 * already because of the other one 2477 */ 2478 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2479 net_enable_timestamp(); 2480 } 2481 } 2482 2483 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2484 int level, int type) 2485 { 2486 struct sock_exterr_skb *serr; 2487 struct sk_buff *skb, *skb2; 2488 int copied, err; 2489 2490 err = -EAGAIN; 2491 skb = skb_dequeue(&sk->sk_error_queue); 2492 if (skb == NULL) 2493 goto out; 2494 2495 copied = skb->len; 2496 if (copied > len) { 2497 msg->msg_flags |= MSG_TRUNC; 2498 copied = len; 2499 } 2500 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 2501 if (err) 2502 goto out_free_skb; 2503 2504 sock_recv_timestamp(msg, sk, skb); 2505 2506 serr = SKB_EXT_ERR(skb); 2507 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2508 2509 msg->msg_flags |= MSG_ERRQUEUE; 2510 err = copied; 2511 2512 /* Reset and regenerate socket error */ 2513 spin_lock_bh(&sk->sk_error_queue.lock); 2514 sk->sk_err = 0; 2515 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 2516 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 2517 spin_unlock_bh(&sk->sk_error_queue.lock); 2518 sk->sk_error_report(sk); 2519 } else 2520 spin_unlock_bh(&sk->sk_error_queue.lock); 2521 2522 out_free_skb: 2523 kfree_skb(skb); 2524 out: 2525 return err; 2526 } 2527 EXPORT_SYMBOL(sock_recv_errqueue); 2528 2529 /* 2530 * Get a socket option on an socket. 2531 * 2532 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2533 * asynchronous errors should be reported by getsockopt. We assume 2534 * this means if you specify SO_ERROR (otherwise whats the point of it). 2535 */ 2536 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2537 char __user *optval, int __user *optlen) 2538 { 2539 struct sock *sk = sock->sk; 2540 2541 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2542 } 2543 EXPORT_SYMBOL(sock_common_getsockopt); 2544 2545 #ifdef CONFIG_COMPAT 2546 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2547 char __user *optval, int __user *optlen) 2548 { 2549 struct sock *sk = sock->sk; 2550 2551 if (sk->sk_prot->compat_getsockopt != NULL) 2552 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2553 optval, optlen); 2554 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2555 } 2556 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2557 #endif 2558 2559 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2560 struct msghdr *msg, size_t size, int flags) 2561 { 2562 struct sock *sk = sock->sk; 2563 int addr_len = 0; 2564 int err; 2565 2566 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2567 flags & ~MSG_DONTWAIT, &addr_len); 2568 if (err >= 0) 2569 msg->msg_namelen = addr_len; 2570 return err; 2571 } 2572 EXPORT_SYMBOL(sock_common_recvmsg); 2573 2574 /* 2575 * Set socket options on an inet socket. 2576 */ 2577 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2578 char __user *optval, unsigned int optlen) 2579 { 2580 struct sock *sk = sock->sk; 2581 2582 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2583 } 2584 EXPORT_SYMBOL(sock_common_setsockopt); 2585 2586 #ifdef CONFIG_COMPAT 2587 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2588 char __user *optval, unsigned int optlen) 2589 { 2590 struct sock *sk = sock->sk; 2591 2592 if (sk->sk_prot->compat_setsockopt != NULL) 2593 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2594 optval, optlen); 2595 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2596 } 2597 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2598 #endif 2599 2600 void sk_common_release(struct sock *sk) 2601 { 2602 if (sk->sk_prot->destroy) 2603 sk->sk_prot->destroy(sk); 2604 2605 /* 2606 * Observation: when sock_common_release is called, processes have 2607 * no access to socket. But net still has. 2608 * Step one, detach it from networking: 2609 * 2610 * A. Remove from hash tables. 2611 */ 2612 2613 sk->sk_prot->unhash(sk); 2614 2615 /* 2616 * In this point socket cannot receive new packets, but it is possible 2617 * that some packets are in flight because some CPU runs receiver and 2618 * did hash table lookup before we unhashed socket. They will achieve 2619 * receive queue and will be purged by socket destructor. 2620 * 2621 * Also we still have packets pending on receive queue and probably, 2622 * our own packets waiting in device queues. sock_destroy will drain 2623 * receive queue, but transmitted packets will delay socket destruction 2624 * until the last reference will be released. 2625 */ 2626 2627 sock_orphan(sk); 2628 2629 xfrm_sk_free_policy(sk); 2630 2631 sk_refcnt_debug_release(sk); 2632 2633 if (sk->sk_frag.page) { 2634 put_page(sk->sk_frag.page); 2635 sk->sk_frag.page = NULL; 2636 } 2637 2638 sock_put(sk); 2639 } 2640 EXPORT_SYMBOL(sk_common_release); 2641 2642 #ifdef CONFIG_PROC_FS 2643 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2644 struct prot_inuse { 2645 int val[PROTO_INUSE_NR]; 2646 }; 2647 2648 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2649 2650 #ifdef CONFIG_NET_NS 2651 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2652 { 2653 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2654 } 2655 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2656 2657 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2658 { 2659 int cpu, idx = prot->inuse_idx; 2660 int res = 0; 2661 2662 for_each_possible_cpu(cpu) 2663 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2664 2665 return res >= 0 ? res : 0; 2666 } 2667 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2668 2669 static int __net_init sock_inuse_init_net(struct net *net) 2670 { 2671 net->core.inuse = alloc_percpu(struct prot_inuse); 2672 return net->core.inuse ? 0 : -ENOMEM; 2673 } 2674 2675 static void __net_exit sock_inuse_exit_net(struct net *net) 2676 { 2677 free_percpu(net->core.inuse); 2678 } 2679 2680 static struct pernet_operations net_inuse_ops = { 2681 .init = sock_inuse_init_net, 2682 .exit = sock_inuse_exit_net, 2683 }; 2684 2685 static __init int net_inuse_init(void) 2686 { 2687 if (register_pernet_subsys(&net_inuse_ops)) 2688 panic("Cannot initialize net inuse counters"); 2689 2690 return 0; 2691 } 2692 2693 core_initcall(net_inuse_init); 2694 #else 2695 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2696 2697 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2698 { 2699 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2700 } 2701 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2702 2703 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2704 { 2705 int cpu, idx = prot->inuse_idx; 2706 int res = 0; 2707 2708 for_each_possible_cpu(cpu) 2709 res += per_cpu(prot_inuse, cpu).val[idx]; 2710 2711 return res >= 0 ? res : 0; 2712 } 2713 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2714 #endif 2715 2716 static void assign_proto_idx(struct proto *prot) 2717 { 2718 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2719 2720 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2721 pr_err("PROTO_INUSE_NR exhausted\n"); 2722 return; 2723 } 2724 2725 set_bit(prot->inuse_idx, proto_inuse_idx); 2726 } 2727 2728 static void release_proto_idx(struct proto *prot) 2729 { 2730 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2731 clear_bit(prot->inuse_idx, proto_inuse_idx); 2732 } 2733 #else 2734 static inline void assign_proto_idx(struct proto *prot) 2735 { 2736 } 2737 2738 static inline void release_proto_idx(struct proto *prot) 2739 { 2740 } 2741 #endif 2742 2743 int proto_register(struct proto *prot, int alloc_slab) 2744 { 2745 if (alloc_slab) { 2746 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2747 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2748 NULL); 2749 2750 if (prot->slab == NULL) { 2751 pr_crit("%s: Can't create sock SLAB cache!\n", 2752 prot->name); 2753 goto out; 2754 } 2755 2756 if (prot->rsk_prot != NULL) { 2757 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2758 if (prot->rsk_prot->slab_name == NULL) 2759 goto out_free_sock_slab; 2760 2761 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2762 prot->rsk_prot->obj_size, 0, 2763 SLAB_HWCACHE_ALIGN, NULL); 2764 2765 if (prot->rsk_prot->slab == NULL) { 2766 pr_crit("%s: Can't create request sock SLAB cache!\n", 2767 prot->name); 2768 goto out_free_request_sock_slab_name; 2769 } 2770 } 2771 2772 if (prot->twsk_prot != NULL) { 2773 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2774 2775 if (prot->twsk_prot->twsk_slab_name == NULL) 2776 goto out_free_request_sock_slab; 2777 2778 prot->twsk_prot->twsk_slab = 2779 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2780 prot->twsk_prot->twsk_obj_size, 2781 0, 2782 SLAB_HWCACHE_ALIGN | 2783 prot->slab_flags, 2784 NULL); 2785 if (prot->twsk_prot->twsk_slab == NULL) 2786 goto out_free_timewait_sock_slab_name; 2787 } 2788 } 2789 2790 mutex_lock(&proto_list_mutex); 2791 list_add(&prot->node, &proto_list); 2792 assign_proto_idx(prot); 2793 mutex_unlock(&proto_list_mutex); 2794 return 0; 2795 2796 out_free_timewait_sock_slab_name: 2797 kfree(prot->twsk_prot->twsk_slab_name); 2798 out_free_request_sock_slab: 2799 if (prot->rsk_prot && prot->rsk_prot->slab) { 2800 kmem_cache_destroy(prot->rsk_prot->slab); 2801 prot->rsk_prot->slab = NULL; 2802 } 2803 out_free_request_sock_slab_name: 2804 if (prot->rsk_prot) 2805 kfree(prot->rsk_prot->slab_name); 2806 out_free_sock_slab: 2807 kmem_cache_destroy(prot->slab); 2808 prot->slab = NULL; 2809 out: 2810 return -ENOBUFS; 2811 } 2812 EXPORT_SYMBOL(proto_register); 2813 2814 void proto_unregister(struct proto *prot) 2815 { 2816 mutex_lock(&proto_list_mutex); 2817 release_proto_idx(prot); 2818 list_del(&prot->node); 2819 mutex_unlock(&proto_list_mutex); 2820 2821 if (prot->slab != NULL) { 2822 kmem_cache_destroy(prot->slab); 2823 prot->slab = NULL; 2824 } 2825 2826 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2827 kmem_cache_destroy(prot->rsk_prot->slab); 2828 kfree(prot->rsk_prot->slab_name); 2829 prot->rsk_prot->slab = NULL; 2830 } 2831 2832 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2833 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2834 kfree(prot->twsk_prot->twsk_slab_name); 2835 prot->twsk_prot->twsk_slab = NULL; 2836 } 2837 } 2838 EXPORT_SYMBOL(proto_unregister); 2839 2840 #ifdef CONFIG_PROC_FS 2841 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2842 __acquires(proto_list_mutex) 2843 { 2844 mutex_lock(&proto_list_mutex); 2845 return seq_list_start_head(&proto_list, *pos); 2846 } 2847 2848 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2849 { 2850 return seq_list_next(v, &proto_list, pos); 2851 } 2852 2853 static void proto_seq_stop(struct seq_file *seq, void *v) 2854 __releases(proto_list_mutex) 2855 { 2856 mutex_unlock(&proto_list_mutex); 2857 } 2858 2859 static char proto_method_implemented(const void *method) 2860 { 2861 return method == NULL ? 'n' : 'y'; 2862 } 2863 static long sock_prot_memory_allocated(struct proto *proto) 2864 { 2865 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2866 } 2867 2868 static char *sock_prot_memory_pressure(struct proto *proto) 2869 { 2870 return proto->memory_pressure != NULL ? 2871 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2872 } 2873 2874 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2875 { 2876 2877 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2878 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2879 proto->name, 2880 proto->obj_size, 2881 sock_prot_inuse_get(seq_file_net(seq), proto), 2882 sock_prot_memory_allocated(proto), 2883 sock_prot_memory_pressure(proto), 2884 proto->max_header, 2885 proto->slab == NULL ? "no" : "yes", 2886 module_name(proto->owner), 2887 proto_method_implemented(proto->close), 2888 proto_method_implemented(proto->connect), 2889 proto_method_implemented(proto->disconnect), 2890 proto_method_implemented(proto->accept), 2891 proto_method_implemented(proto->ioctl), 2892 proto_method_implemented(proto->init), 2893 proto_method_implemented(proto->destroy), 2894 proto_method_implemented(proto->shutdown), 2895 proto_method_implemented(proto->setsockopt), 2896 proto_method_implemented(proto->getsockopt), 2897 proto_method_implemented(proto->sendmsg), 2898 proto_method_implemented(proto->recvmsg), 2899 proto_method_implemented(proto->sendpage), 2900 proto_method_implemented(proto->bind), 2901 proto_method_implemented(proto->backlog_rcv), 2902 proto_method_implemented(proto->hash), 2903 proto_method_implemented(proto->unhash), 2904 proto_method_implemented(proto->get_port), 2905 proto_method_implemented(proto->enter_memory_pressure)); 2906 } 2907 2908 static int proto_seq_show(struct seq_file *seq, void *v) 2909 { 2910 if (v == &proto_list) 2911 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2912 "protocol", 2913 "size", 2914 "sockets", 2915 "memory", 2916 "press", 2917 "maxhdr", 2918 "slab", 2919 "module", 2920 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2921 else 2922 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2923 return 0; 2924 } 2925 2926 static const struct seq_operations proto_seq_ops = { 2927 .start = proto_seq_start, 2928 .next = proto_seq_next, 2929 .stop = proto_seq_stop, 2930 .show = proto_seq_show, 2931 }; 2932 2933 static int proto_seq_open(struct inode *inode, struct file *file) 2934 { 2935 return seq_open_net(inode, file, &proto_seq_ops, 2936 sizeof(struct seq_net_private)); 2937 } 2938 2939 static const struct file_operations proto_seq_fops = { 2940 .owner = THIS_MODULE, 2941 .open = proto_seq_open, 2942 .read = seq_read, 2943 .llseek = seq_lseek, 2944 .release = seq_release_net, 2945 }; 2946 2947 static __net_init int proto_init_net(struct net *net) 2948 { 2949 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2950 return -ENOMEM; 2951 2952 return 0; 2953 } 2954 2955 static __net_exit void proto_exit_net(struct net *net) 2956 { 2957 remove_proc_entry("protocols", net->proc_net); 2958 } 2959 2960 2961 static __net_initdata struct pernet_operations proto_net_ops = { 2962 .init = proto_init_net, 2963 .exit = proto_exit_net, 2964 }; 2965 2966 static int __init proto_init(void) 2967 { 2968 return register_pernet_subsys(&proto_net_ops); 2969 } 2970 2971 subsys_initcall(proto_init); 2972 2973 #endif /* PROC_FS */ 2974