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/types.h> 97 #include <linux/socket.h> 98 #include <linux/in.h> 99 #include <linux/kernel.h> 100 #include <linux/module.h> 101 #include <linux/proc_fs.h> 102 #include <linux/seq_file.h> 103 #include <linux/sched.h> 104 #include <linux/timer.h> 105 #include <linux/string.h> 106 #include <linux/sockios.h> 107 #include <linux/net.h> 108 #include <linux/mm.h> 109 #include <linux/slab.h> 110 #include <linux/interrupt.h> 111 #include <linux/poll.h> 112 #include <linux/tcp.h> 113 #include <linux/init.h> 114 #include <linux/highmem.h> 115 #include <linux/user_namespace.h> 116 #include <linux/static_key.h> 117 #include <linux/memcontrol.h> 118 #include <linux/prefetch.h> 119 120 #include <asm/uaccess.h> 121 122 #include <linux/netdevice.h> 123 #include <net/protocol.h> 124 #include <linux/skbuff.h> 125 #include <net/net_namespace.h> 126 #include <net/request_sock.h> 127 #include <net/sock.h> 128 #include <linux/net_tstamp.h> 129 #include <net/xfrm.h> 130 #include <linux/ipsec.h> 131 #include <net/cls_cgroup.h> 132 #include <net/netprio_cgroup.h> 133 134 #include <linux/filter.h> 135 136 #include <trace/events/sock.h> 137 138 #ifdef CONFIG_INET 139 #include <net/tcp.h> 140 #endif 141 142 static DEFINE_MUTEX(proto_list_mutex); 143 static LIST_HEAD(proto_list); 144 145 #ifdef CONFIG_MEMCG_KMEM 146 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 147 { 148 struct proto *proto; 149 int ret = 0; 150 151 mutex_lock(&proto_list_mutex); 152 list_for_each_entry(proto, &proto_list, node) { 153 if (proto->init_cgroup) { 154 ret = proto->init_cgroup(memcg, ss); 155 if (ret) 156 goto out; 157 } 158 } 159 160 mutex_unlock(&proto_list_mutex); 161 return ret; 162 out: 163 list_for_each_entry_continue_reverse(proto, &proto_list, node) 164 if (proto->destroy_cgroup) 165 proto->destroy_cgroup(memcg); 166 mutex_unlock(&proto_list_mutex); 167 return ret; 168 } 169 170 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 171 { 172 struct proto *proto; 173 174 mutex_lock(&proto_list_mutex); 175 list_for_each_entry_reverse(proto, &proto_list, node) 176 if (proto->destroy_cgroup) 177 proto->destroy_cgroup(memcg); 178 mutex_unlock(&proto_list_mutex); 179 } 180 #endif 181 182 /* 183 * Each address family might have different locking rules, so we have 184 * one slock key per address family: 185 */ 186 static struct lock_class_key af_family_keys[AF_MAX]; 187 static struct lock_class_key af_family_slock_keys[AF_MAX]; 188 189 #if defined(CONFIG_MEMCG_KMEM) 190 struct static_key memcg_socket_limit_enabled; 191 EXPORT_SYMBOL(memcg_socket_limit_enabled); 192 #endif 193 194 /* 195 * Make lock validator output more readable. (we pre-construct these 196 * strings build-time, so that runtime initialization of socket 197 * locks is fast): 198 */ 199 static const char *const af_family_key_strings[AF_MAX+1] = { 200 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 201 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 202 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 203 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 204 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 205 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 206 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 207 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 208 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 209 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 210 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 211 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 212 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 213 "sk_lock-AF_NFC" , "sk_lock-AF_MAX" 214 }; 215 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 216 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 217 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 218 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 219 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 220 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 221 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 222 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 223 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 224 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 225 "slock-27" , "slock-28" , "slock-AF_CAN" , 226 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 227 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 228 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 229 "slock-AF_NFC" , "slock-AF_MAX" 230 }; 231 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 232 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 233 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 234 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 235 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 236 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 237 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 238 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 239 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 240 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 241 "clock-27" , "clock-28" , "clock-AF_CAN" , 242 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 243 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 244 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 245 "clock-AF_NFC" , "clock-AF_MAX" 246 }; 247 248 /* 249 * sk_callback_lock locking rules are per-address-family, 250 * so split the lock classes by using a per-AF key: 251 */ 252 static struct lock_class_key af_callback_keys[AF_MAX]; 253 254 /* Take into consideration the size of the struct sk_buff overhead in the 255 * determination of these values, since that is non-constant across 256 * platforms. This makes socket queueing behavior and performance 257 * not depend upon such differences. 258 */ 259 #define _SK_MEM_PACKETS 256 260 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 261 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 262 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 263 264 /* Run time adjustable parameters. */ 265 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 266 EXPORT_SYMBOL(sysctl_wmem_max); 267 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 268 EXPORT_SYMBOL(sysctl_rmem_max); 269 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 270 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 271 272 /* Maximal space eaten by iovec or ancillary data plus some space */ 273 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 274 EXPORT_SYMBOL(sysctl_optmem_max); 275 276 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 277 EXPORT_SYMBOL_GPL(memalloc_socks); 278 279 /** 280 * sk_set_memalloc - sets %SOCK_MEMALLOC 281 * @sk: socket to set it on 282 * 283 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 284 * It's the responsibility of the admin to adjust min_free_kbytes 285 * to meet the requirements 286 */ 287 void sk_set_memalloc(struct sock *sk) 288 { 289 sock_set_flag(sk, SOCK_MEMALLOC); 290 sk->sk_allocation |= __GFP_MEMALLOC; 291 static_key_slow_inc(&memalloc_socks); 292 } 293 EXPORT_SYMBOL_GPL(sk_set_memalloc); 294 295 void sk_clear_memalloc(struct sock *sk) 296 { 297 sock_reset_flag(sk, SOCK_MEMALLOC); 298 sk->sk_allocation &= ~__GFP_MEMALLOC; 299 static_key_slow_dec(&memalloc_socks); 300 301 /* 302 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 303 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 304 * it has rmem allocations there is a risk that the user of the 305 * socket cannot make forward progress due to exceeding the rmem 306 * limits. By rights, sk_clear_memalloc() should only be called 307 * on sockets being torn down but warn and reset the accounting if 308 * that assumption breaks. 309 */ 310 if (WARN_ON(sk->sk_forward_alloc)) 311 sk_mem_reclaim(sk); 312 } 313 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 314 315 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 316 { 317 int ret; 318 unsigned long pflags = current->flags; 319 320 /* these should have been dropped before queueing */ 321 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 322 323 current->flags |= PF_MEMALLOC; 324 ret = sk->sk_backlog_rcv(sk, skb); 325 tsk_restore_flags(current, pflags, PF_MEMALLOC); 326 327 return ret; 328 } 329 EXPORT_SYMBOL(__sk_backlog_rcv); 330 331 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 332 { 333 struct timeval tv; 334 335 if (optlen < sizeof(tv)) 336 return -EINVAL; 337 if (copy_from_user(&tv, optval, sizeof(tv))) 338 return -EFAULT; 339 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 340 return -EDOM; 341 342 if (tv.tv_sec < 0) { 343 static int warned __read_mostly; 344 345 *timeo_p = 0; 346 if (warned < 10 && net_ratelimit()) { 347 warned++; 348 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 349 __func__, current->comm, task_pid_nr(current)); 350 } 351 return 0; 352 } 353 *timeo_p = MAX_SCHEDULE_TIMEOUT; 354 if (tv.tv_sec == 0 && tv.tv_usec == 0) 355 return 0; 356 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 357 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 358 return 0; 359 } 360 361 static void sock_warn_obsolete_bsdism(const char *name) 362 { 363 static int warned; 364 static char warncomm[TASK_COMM_LEN]; 365 if (strcmp(warncomm, current->comm) && warned < 5) { 366 strcpy(warncomm, current->comm); 367 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 368 warncomm, name); 369 warned++; 370 } 371 } 372 373 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 374 375 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 376 { 377 if (sk->sk_flags & flags) { 378 sk->sk_flags &= ~flags; 379 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 380 net_disable_timestamp(); 381 } 382 } 383 384 385 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 386 { 387 int err; 388 int skb_len; 389 unsigned long flags; 390 struct sk_buff_head *list = &sk->sk_receive_queue; 391 392 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 393 atomic_inc(&sk->sk_drops); 394 trace_sock_rcvqueue_full(sk, skb); 395 return -ENOMEM; 396 } 397 398 err = sk_filter(sk, skb); 399 if (err) 400 return err; 401 402 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 403 atomic_inc(&sk->sk_drops); 404 return -ENOBUFS; 405 } 406 407 skb->dev = NULL; 408 skb_set_owner_r(skb, sk); 409 410 /* Cache the SKB length before we tack it onto the receive 411 * queue. Once it is added it no longer belongs to us and 412 * may be freed by other threads of control pulling packets 413 * from the queue. 414 */ 415 skb_len = skb->len; 416 417 /* we escape from rcu protected region, make sure we dont leak 418 * a norefcounted dst 419 */ 420 skb_dst_force(skb); 421 422 spin_lock_irqsave(&list->lock, flags); 423 skb->dropcount = atomic_read(&sk->sk_drops); 424 __skb_queue_tail(list, skb); 425 spin_unlock_irqrestore(&list->lock, flags); 426 427 if (!sock_flag(sk, SOCK_DEAD)) 428 sk->sk_data_ready(sk, skb_len); 429 return 0; 430 } 431 EXPORT_SYMBOL(sock_queue_rcv_skb); 432 433 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 434 { 435 int rc = NET_RX_SUCCESS; 436 437 if (sk_filter(sk, skb)) 438 goto discard_and_relse; 439 440 skb->dev = NULL; 441 442 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) { 443 atomic_inc(&sk->sk_drops); 444 goto discard_and_relse; 445 } 446 if (nested) 447 bh_lock_sock_nested(sk); 448 else 449 bh_lock_sock(sk); 450 if (!sock_owned_by_user(sk)) { 451 /* 452 * trylock + unlock semantics: 453 */ 454 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 455 456 rc = sk_backlog_rcv(sk, skb); 457 458 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 459 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 460 bh_unlock_sock(sk); 461 atomic_inc(&sk->sk_drops); 462 goto discard_and_relse; 463 } 464 465 bh_unlock_sock(sk); 466 out: 467 sock_put(sk); 468 return rc; 469 discard_and_relse: 470 kfree_skb(skb); 471 goto out; 472 } 473 EXPORT_SYMBOL(sk_receive_skb); 474 475 void sk_reset_txq(struct sock *sk) 476 { 477 sk_tx_queue_clear(sk); 478 } 479 EXPORT_SYMBOL(sk_reset_txq); 480 481 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 482 { 483 struct dst_entry *dst = __sk_dst_get(sk); 484 485 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 486 sk_tx_queue_clear(sk); 487 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 488 dst_release(dst); 489 return NULL; 490 } 491 492 return dst; 493 } 494 EXPORT_SYMBOL(__sk_dst_check); 495 496 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 497 { 498 struct dst_entry *dst = sk_dst_get(sk); 499 500 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 501 sk_dst_reset(sk); 502 dst_release(dst); 503 return NULL; 504 } 505 506 return dst; 507 } 508 EXPORT_SYMBOL(sk_dst_check); 509 510 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 511 int optlen) 512 { 513 int ret = -ENOPROTOOPT; 514 #ifdef CONFIG_NETDEVICES 515 struct net *net = sock_net(sk); 516 char devname[IFNAMSIZ]; 517 int index; 518 519 /* Sorry... */ 520 ret = -EPERM; 521 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 522 goto out; 523 524 ret = -EINVAL; 525 if (optlen < 0) 526 goto out; 527 528 /* Bind this socket to a particular device like "eth0", 529 * as specified in the passed interface name. If the 530 * name is "" or the option length is zero the socket 531 * is not bound. 532 */ 533 if (optlen > IFNAMSIZ - 1) 534 optlen = IFNAMSIZ - 1; 535 memset(devname, 0, sizeof(devname)); 536 537 ret = -EFAULT; 538 if (copy_from_user(devname, optval, optlen)) 539 goto out; 540 541 index = 0; 542 if (devname[0] != '\0') { 543 struct net_device *dev; 544 545 rcu_read_lock(); 546 dev = dev_get_by_name_rcu(net, devname); 547 if (dev) 548 index = dev->ifindex; 549 rcu_read_unlock(); 550 ret = -ENODEV; 551 if (!dev) 552 goto out; 553 } 554 555 lock_sock(sk); 556 sk->sk_bound_dev_if = index; 557 sk_dst_reset(sk); 558 release_sock(sk); 559 560 ret = 0; 561 562 out: 563 #endif 564 565 return ret; 566 } 567 568 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 569 int __user *optlen, int len) 570 { 571 int ret = -ENOPROTOOPT; 572 #ifdef CONFIG_NETDEVICES 573 struct net *net = sock_net(sk); 574 struct net_device *dev; 575 char devname[IFNAMSIZ]; 576 unsigned seq; 577 578 if (sk->sk_bound_dev_if == 0) { 579 len = 0; 580 goto zero; 581 } 582 583 ret = -EINVAL; 584 if (len < IFNAMSIZ) 585 goto out; 586 587 retry: 588 seq = read_seqcount_begin(&devnet_rename_seq); 589 rcu_read_lock(); 590 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if); 591 ret = -ENODEV; 592 if (!dev) { 593 rcu_read_unlock(); 594 goto out; 595 } 596 597 strcpy(devname, dev->name); 598 rcu_read_unlock(); 599 if (read_seqcount_retry(&devnet_rename_seq, seq)) 600 goto retry; 601 602 len = strlen(devname) + 1; 603 604 ret = -EFAULT; 605 if (copy_to_user(optval, devname, len)) 606 goto out; 607 608 zero: 609 ret = -EFAULT; 610 if (put_user(len, optlen)) 611 goto out; 612 613 ret = 0; 614 615 out: 616 #endif 617 618 return ret; 619 } 620 621 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 622 { 623 if (valbool) 624 sock_set_flag(sk, bit); 625 else 626 sock_reset_flag(sk, bit); 627 } 628 629 /* 630 * This is meant for all protocols to use and covers goings on 631 * at the socket level. Everything here is generic. 632 */ 633 634 int sock_setsockopt(struct socket *sock, int level, int optname, 635 char __user *optval, unsigned int optlen) 636 { 637 struct sock *sk = sock->sk; 638 int val; 639 int valbool; 640 struct linger ling; 641 int ret = 0; 642 643 /* 644 * Options without arguments 645 */ 646 647 if (optname == SO_BINDTODEVICE) 648 return sock_setbindtodevice(sk, optval, optlen); 649 650 if (optlen < sizeof(int)) 651 return -EINVAL; 652 653 if (get_user(val, (int __user *)optval)) 654 return -EFAULT; 655 656 valbool = val ? 1 : 0; 657 658 lock_sock(sk); 659 660 switch (optname) { 661 case SO_DEBUG: 662 if (val && !capable(CAP_NET_ADMIN)) 663 ret = -EACCES; 664 else 665 sock_valbool_flag(sk, SOCK_DBG, valbool); 666 break; 667 case SO_REUSEADDR: 668 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 669 break; 670 case SO_REUSEPORT: 671 sk->sk_reuseport = valbool; 672 break; 673 case SO_TYPE: 674 case SO_PROTOCOL: 675 case SO_DOMAIN: 676 case SO_ERROR: 677 ret = -ENOPROTOOPT; 678 break; 679 case SO_DONTROUTE: 680 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 681 break; 682 case SO_BROADCAST: 683 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 684 break; 685 case SO_SNDBUF: 686 /* Don't error on this BSD doesn't and if you think 687 * about it this is right. Otherwise apps have to 688 * play 'guess the biggest size' games. RCVBUF/SNDBUF 689 * are treated in BSD as hints 690 */ 691 val = min_t(u32, val, sysctl_wmem_max); 692 set_sndbuf: 693 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 694 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 695 /* Wake up sending tasks if we upped the value. */ 696 sk->sk_write_space(sk); 697 break; 698 699 case SO_SNDBUFFORCE: 700 if (!capable(CAP_NET_ADMIN)) { 701 ret = -EPERM; 702 break; 703 } 704 goto set_sndbuf; 705 706 case SO_RCVBUF: 707 /* Don't error on this BSD doesn't and if you think 708 * about it this is right. Otherwise apps have to 709 * play 'guess the biggest size' games. RCVBUF/SNDBUF 710 * are treated in BSD as hints 711 */ 712 val = min_t(u32, val, sysctl_rmem_max); 713 set_rcvbuf: 714 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 715 /* 716 * We double it on the way in to account for 717 * "struct sk_buff" etc. overhead. Applications 718 * assume that the SO_RCVBUF setting they make will 719 * allow that much actual data to be received on that 720 * socket. 721 * 722 * Applications are unaware that "struct sk_buff" and 723 * other overheads allocate from the receive buffer 724 * during socket buffer allocation. 725 * 726 * And after considering the possible alternatives, 727 * returning the value we actually used in getsockopt 728 * is the most desirable behavior. 729 */ 730 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 731 break; 732 733 case SO_RCVBUFFORCE: 734 if (!capable(CAP_NET_ADMIN)) { 735 ret = -EPERM; 736 break; 737 } 738 goto set_rcvbuf; 739 740 case SO_KEEPALIVE: 741 #ifdef CONFIG_INET 742 if (sk->sk_protocol == IPPROTO_TCP && 743 sk->sk_type == SOCK_STREAM) 744 tcp_set_keepalive(sk, valbool); 745 #endif 746 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 747 break; 748 749 case SO_OOBINLINE: 750 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 751 break; 752 753 case SO_NO_CHECK: 754 sk->sk_no_check = valbool; 755 break; 756 757 case SO_PRIORITY: 758 if ((val >= 0 && val <= 6) || 759 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 760 sk->sk_priority = val; 761 else 762 ret = -EPERM; 763 break; 764 765 case SO_LINGER: 766 if (optlen < sizeof(ling)) { 767 ret = -EINVAL; /* 1003.1g */ 768 break; 769 } 770 if (copy_from_user(&ling, optval, sizeof(ling))) { 771 ret = -EFAULT; 772 break; 773 } 774 if (!ling.l_onoff) 775 sock_reset_flag(sk, SOCK_LINGER); 776 else { 777 #if (BITS_PER_LONG == 32) 778 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 779 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 780 else 781 #endif 782 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 783 sock_set_flag(sk, SOCK_LINGER); 784 } 785 break; 786 787 case SO_BSDCOMPAT: 788 sock_warn_obsolete_bsdism("setsockopt"); 789 break; 790 791 case SO_PASSCRED: 792 if (valbool) 793 set_bit(SOCK_PASSCRED, &sock->flags); 794 else 795 clear_bit(SOCK_PASSCRED, &sock->flags); 796 break; 797 798 case SO_TIMESTAMP: 799 case SO_TIMESTAMPNS: 800 if (valbool) { 801 if (optname == SO_TIMESTAMP) 802 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 803 else 804 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 805 sock_set_flag(sk, SOCK_RCVTSTAMP); 806 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 807 } else { 808 sock_reset_flag(sk, SOCK_RCVTSTAMP); 809 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 810 } 811 break; 812 813 case SO_TIMESTAMPING: 814 if (val & ~SOF_TIMESTAMPING_MASK) { 815 ret = -EINVAL; 816 break; 817 } 818 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE, 819 val & SOF_TIMESTAMPING_TX_HARDWARE); 820 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE, 821 val & SOF_TIMESTAMPING_TX_SOFTWARE); 822 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE, 823 val & SOF_TIMESTAMPING_RX_HARDWARE); 824 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 825 sock_enable_timestamp(sk, 826 SOCK_TIMESTAMPING_RX_SOFTWARE); 827 else 828 sock_disable_timestamp(sk, 829 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 830 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE, 831 val & SOF_TIMESTAMPING_SOFTWARE); 832 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE, 833 val & SOF_TIMESTAMPING_SYS_HARDWARE); 834 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE, 835 val & SOF_TIMESTAMPING_RAW_HARDWARE); 836 break; 837 838 case SO_RCVLOWAT: 839 if (val < 0) 840 val = INT_MAX; 841 sk->sk_rcvlowat = val ? : 1; 842 break; 843 844 case SO_RCVTIMEO: 845 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 846 break; 847 848 case SO_SNDTIMEO: 849 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 850 break; 851 852 case SO_ATTACH_FILTER: 853 ret = -EINVAL; 854 if (optlen == sizeof(struct sock_fprog)) { 855 struct sock_fprog fprog; 856 857 ret = -EFAULT; 858 if (copy_from_user(&fprog, optval, sizeof(fprog))) 859 break; 860 861 ret = sk_attach_filter(&fprog, sk); 862 } 863 break; 864 865 case SO_DETACH_FILTER: 866 ret = sk_detach_filter(sk); 867 break; 868 869 case SO_LOCK_FILTER: 870 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 871 ret = -EPERM; 872 else 873 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 874 break; 875 876 case SO_PASSSEC: 877 if (valbool) 878 set_bit(SOCK_PASSSEC, &sock->flags); 879 else 880 clear_bit(SOCK_PASSSEC, &sock->flags); 881 break; 882 case SO_MARK: 883 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 884 ret = -EPERM; 885 else 886 sk->sk_mark = val; 887 break; 888 889 /* We implement the SO_SNDLOWAT etc to 890 not be settable (1003.1g 5.3) */ 891 case SO_RXQ_OVFL: 892 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 893 break; 894 895 case SO_WIFI_STATUS: 896 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 897 break; 898 899 case SO_PEEK_OFF: 900 if (sock->ops->set_peek_off) 901 sock->ops->set_peek_off(sk, val); 902 else 903 ret = -EOPNOTSUPP; 904 break; 905 906 case SO_NOFCS: 907 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 908 break; 909 910 default: 911 ret = -ENOPROTOOPT; 912 break; 913 } 914 release_sock(sk); 915 return ret; 916 } 917 EXPORT_SYMBOL(sock_setsockopt); 918 919 920 void cred_to_ucred(struct pid *pid, const struct cred *cred, 921 struct ucred *ucred) 922 { 923 ucred->pid = pid_vnr(pid); 924 ucred->uid = ucred->gid = -1; 925 if (cred) { 926 struct user_namespace *current_ns = current_user_ns(); 927 928 ucred->uid = from_kuid_munged(current_ns, cred->euid); 929 ucred->gid = from_kgid_munged(current_ns, cred->egid); 930 } 931 } 932 EXPORT_SYMBOL_GPL(cred_to_ucred); 933 934 int sock_getsockopt(struct socket *sock, int level, int optname, 935 char __user *optval, int __user *optlen) 936 { 937 struct sock *sk = sock->sk; 938 939 union { 940 int val; 941 struct linger ling; 942 struct timeval tm; 943 } v; 944 945 int lv = sizeof(int); 946 int len; 947 948 if (get_user(len, optlen)) 949 return -EFAULT; 950 if (len < 0) 951 return -EINVAL; 952 953 memset(&v, 0, sizeof(v)); 954 955 switch (optname) { 956 case SO_DEBUG: 957 v.val = sock_flag(sk, SOCK_DBG); 958 break; 959 960 case SO_DONTROUTE: 961 v.val = sock_flag(sk, SOCK_LOCALROUTE); 962 break; 963 964 case SO_BROADCAST: 965 v.val = sock_flag(sk, SOCK_BROADCAST); 966 break; 967 968 case SO_SNDBUF: 969 v.val = sk->sk_sndbuf; 970 break; 971 972 case SO_RCVBUF: 973 v.val = sk->sk_rcvbuf; 974 break; 975 976 case SO_REUSEADDR: 977 v.val = sk->sk_reuse; 978 break; 979 980 case SO_REUSEPORT: 981 v.val = sk->sk_reuseport; 982 break; 983 984 case SO_KEEPALIVE: 985 v.val = sock_flag(sk, SOCK_KEEPOPEN); 986 break; 987 988 case SO_TYPE: 989 v.val = sk->sk_type; 990 break; 991 992 case SO_PROTOCOL: 993 v.val = sk->sk_protocol; 994 break; 995 996 case SO_DOMAIN: 997 v.val = sk->sk_family; 998 break; 999 1000 case SO_ERROR: 1001 v.val = -sock_error(sk); 1002 if (v.val == 0) 1003 v.val = xchg(&sk->sk_err_soft, 0); 1004 break; 1005 1006 case SO_OOBINLINE: 1007 v.val = sock_flag(sk, SOCK_URGINLINE); 1008 break; 1009 1010 case SO_NO_CHECK: 1011 v.val = sk->sk_no_check; 1012 break; 1013 1014 case SO_PRIORITY: 1015 v.val = sk->sk_priority; 1016 break; 1017 1018 case SO_LINGER: 1019 lv = sizeof(v.ling); 1020 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1021 v.ling.l_linger = sk->sk_lingertime / HZ; 1022 break; 1023 1024 case SO_BSDCOMPAT: 1025 sock_warn_obsolete_bsdism("getsockopt"); 1026 break; 1027 1028 case SO_TIMESTAMP: 1029 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1030 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1031 break; 1032 1033 case SO_TIMESTAMPNS: 1034 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1035 break; 1036 1037 case SO_TIMESTAMPING: 1038 v.val = 0; 1039 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE)) 1040 v.val |= SOF_TIMESTAMPING_TX_HARDWARE; 1041 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE)) 1042 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE; 1043 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE)) 1044 v.val |= SOF_TIMESTAMPING_RX_HARDWARE; 1045 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) 1046 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE; 1047 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) 1048 v.val |= SOF_TIMESTAMPING_SOFTWARE; 1049 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)) 1050 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE; 1051 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) 1052 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE; 1053 break; 1054 1055 case SO_RCVTIMEO: 1056 lv = sizeof(struct timeval); 1057 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1058 v.tm.tv_sec = 0; 1059 v.tm.tv_usec = 0; 1060 } else { 1061 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1062 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1063 } 1064 break; 1065 1066 case SO_SNDTIMEO: 1067 lv = sizeof(struct timeval); 1068 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1069 v.tm.tv_sec = 0; 1070 v.tm.tv_usec = 0; 1071 } else { 1072 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1073 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1074 } 1075 break; 1076 1077 case SO_RCVLOWAT: 1078 v.val = sk->sk_rcvlowat; 1079 break; 1080 1081 case SO_SNDLOWAT: 1082 v.val = 1; 1083 break; 1084 1085 case SO_PASSCRED: 1086 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1087 break; 1088 1089 case SO_PEERCRED: 1090 { 1091 struct ucred peercred; 1092 if (len > sizeof(peercred)) 1093 len = sizeof(peercred); 1094 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1095 if (copy_to_user(optval, &peercred, len)) 1096 return -EFAULT; 1097 goto lenout; 1098 } 1099 1100 case SO_PEERNAME: 1101 { 1102 char address[128]; 1103 1104 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1105 return -ENOTCONN; 1106 if (lv < len) 1107 return -EINVAL; 1108 if (copy_to_user(optval, address, len)) 1109 return -EFAULT; 1110 goto lenout; 1111 } 1112 1113 /* Dubious BSD thing... Probably nobody even uses it, but 1114 * the UNIX standard wants it for whatever reason... -DaveM 1115 */ 1116 case SO_ACCEPTCONN: 1117 v.val = sk->sk_state == TCP_LISTEN; 1118 break; 1119 1120 case SO_PASSSEC: 1121 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1122 break; 1123 1124 case SO_PEERSEC: 1125 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1126 1127 case SO_MARK: 1128 v.val = sk->sk_mark; 1129 break; 1130 1131 case SO_RXQ_OVFL: 1132 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1133 break; 1134 1135 case SO_WIFI_STATUS: 1136 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1137 break; 1138 1139 case SO_PEEK_OFF: 1140 if (!sock->ops->set_peek_off) 1141 return -EOPNOTSUPP; 1142 1143 v.val = sk->sk_peek_off; 1144 break; 1145 case SO_NOFCS: 1146 v.val = sock_flag(sk, SOCK_NOFCS); 1147 break; 1148 1149 case SO_BINDTODEVICE: 1150 return sock_getbindtodevice(sk, optval, optlen, len); 1151 1152 case SO_GET_FILTER: 1153 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1154 if (len < 0) 1155 return len; 1156 1157 goto lenout; 1158 1159 case SO_LOCK_FILTER: 1160 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1161 break; 1162 1163 default: 1164 return -ENOPROTOOPT; 1165 } 1166 1167 if (len > lv) 1168 len = lv; 1169 if (copy_to_user(optval, &v, len)) 1170 return -EFAULT; 1171 lenout: 1172 if (put_user(len, optlen)) 1173 return -EFAULT; 1174 return 0; 1175 } 1176 1177 /* 1178 * Initialize an sk_lock. 1179 * 1180 * (We also register the sk_lock with the lock validator.) 1181 */ 1182 static inline void sock_lock_init(struct sock *sk) 1183 { 1184 sock_lock_init_class_and_name(sk, 1185 af_family_slock_key_strings[sk->sk_family], 1186 af_family_slock_keys + sk->sk_family, 1187 af_family_key_strings[sk->sk_family], 1188 af_family_keys + sk->sk_family); 1189 } 1190 1191 /* 1192 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1193 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1194 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1195 */ 1196 static void sock_copy(struct sock *nsk, const struct sock *osk) 1197 { 1198 #ifdef CONFIG_SECURITY_NETWORK 1199 void *sptr = nsk->sk_security; 1200 #endif 1201 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1202 1203 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1204 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1205 1206 #ifdef CONFIG_SECURITY_NETWORK 1207 nsk->sk_security = sptr; 1208 security_sk_clone(osk, nsk); 1209 #endif 1210 } 1211 1212 /* 1213 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes 1214 * un-modified. Special care is taken when initializing object to zero. 1215 */ 1216 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1217 { 1218 if (offsetof(struct sock, sk_node.next) != 0) 1219 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1220 memset(&sk->sk_node.pprev, 0, 1221 size - offsetof(struct sock, sk_node.pprev)); 1222 } 1223 1224 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1225 { 1226 unsigned long nulls1, nulls2; 1227 1228 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1229 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1230 if (nulls1 > nulls2) 1231 swap(nulls1, nulls2); 1232 1233 if (nulls1 != 0) 1234 memset((char *)sk, 0, nulls1); 1235 memset((char *)sk + nulls1 + sizeof(void *), 0, 1236 nulls2 - nulls1 - sizeof(void *)); 1237 memset((char *)sk + nulls2 + sizeof(void *), 0, 1238 size - nulls2 - sizeof(void *)); 1239 } 1240 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1241 1242 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1243 int family) 1244 { 1245 struct sock *sk; 1246 struct kmem_cache *slab; 1247 1248 slab = prot->slab; 1249 if (slab != NULL) { 1250 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1251 if (!sk) 1252 return sk; 1253 if (priority & __GFP_ZERO) { 1254 if (prot->clear_sk) 1255 prot->clear_sk(sk, prot->obj_size); 1256 else 1257 sk_prot_clear_nulls(sk, prot->obj_size); 1258 } 1259 } else 1260 sk = kmalloc(prot->obj_size, priority); 1261 1262 if (sk != NULL) { 1263 kmemcheck_annotate_bitfield(sk, flags); 1264 1265 if (security_sk_alloc(sk, family, priority)) 1266 goto out_free; 1267 1268 if (!try_module_get(prot->owner)) 1269 goto out_free_sec; 1270 sk_tx_queue_clear(sk); 1271 } 1272 1273 return sk; 1274 1275 out_free_sec: 1276 security_sk_free(sk); 1277 out_free: 1278 if (slab != NULL) 1279 kmem_cache_free(slab, sk); 1280 else 1281 kfree(sk); 1282 return NULL; 1283 } 1284 1285 static void sk_prot_free(struct proto *prot, struct sock *sk) 1286 { 1287 struct kmem_cache *slab; 1288 struct module *owner; 1289 1290 owner = prot->owner; 1291 slab = prot->slab; 1292 1293 security_sk_free(sk); 1294 if (slab != NULL) 1295 kmem_cache_free(slab, sk); 1296 else 1297 kfree(sk); 1298 module_put(owner); 1299 } 1300 1301 #ifdef CONFIG_CGROUPS 1302 #if IS_ENABLED(CONFIG_NET_CLS_CGROUP) 1303 void sock_update_classid(struct sock *sk, struct task_struct *task) 1304 { 1305 u32 classid; 1306 1307 classid = task_cls_classid(task); 1308 if (classid != sk->sk_classid) 1309 sk->sk_classid = classid; 1310 } 1311 EXPORT_SYMBOL(sock_update_classid); 1312 #endif 1313 1314 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP) 1315 void sock_update_netprioidx(struct sock *sk, struct task_struct *task) 1316 { 1317 if (in_interrupt()) 1318 return; 1319 1320 sk->sk_cgrp_prioidx = task_netprioidx(task); 1321 } 1322 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1323 #endif 1324 #endif 1325 1326 /** 1327 * sk_alloc - All socket objects are allocated here 1328 * @net: the applicable net namespace 1329 * @family: protocol family 1330 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1331 * @prot: struct proto associated with this new sock instance 1332 */ 1333 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1334 struct proto *prot) 1335 { 1336 struct sock *sk; 1337 1338 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1339 if (sk) { 1340 sk->sk_family = family; 1341 /* 1342 * See comment in struct sock definition to understand 1343 * why we need sk_prot_creator -acme 1344 */ 1345 sk->sk_prot = sk->sk_prot_creator = prot; 1346 sock_lock_init(sk); 1347 sock_net_set(sk, get_net(net)); 1348 atomic_set(&sk->sk_wmem_alloc, 1); 1349 1350 sock_update_classid(sk, current); 1351 sock_update_netprioidx(sk, current); 1352 } 1353 1354 return sk; 1355 } 1356 EXPORT_SYMBOL(sk_alloc); 1357 1358 static void __sk_free(struct sock *sk) 1359 { 1360 struct sk_filter *filter; 1361 1362 if (sk->sk_destruct) 1363 sk->sk_destruct(sk); 1364 1365 filter = rcu_dereference_check(sk->sk_filter, 1366 atomic_read(&sk->sk_wmem_alloc) == 0); 1367 if (filter) { 1368 sk_filter_uncharge(sk, filter); 1369 RCU_INIT_POINTER(sk->sk_filter, NULL); 1370 } 1371 1372 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1373 1374 if (atomic_read(&sk->sk_omem_alloc)) 1375 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1376 __func__, atomic_read(&sk->sk_omem_alloc)); 1377 1378 if (sk->sk_peer_cred) 1379 put_cred(sk->sk_peer_cred); 1380 put_pid(sk->sk_peer_pid); 1381 put_net(sock_net(sk)); 1382 sk_prot_free(sk->sk_prot_creator, sk); 1383 } 1384 1385 void sk_free(struct sock *sk) 1386 { 1387 /* 1388 * We subtract one from sk_wmem_alloc and can know if 1389 * some packets are still in some tx queue. 1390 * If not null, sock_wfree() will call __sk_free(sk) later 1391 */ 1392 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1393 __sk_free(sk); 1394 } 1395 EXPORT_SYMBOL(sk_free); 1396 1397 /* 1398 * Last sock_put should drop reference to sk->sk_net. It has already 1399 * been dropped in sk_change_net. Taking reference to stopping namespace 1400 * is not an option. 1401 * Take reference to a socket to remove it from hash _alive_ and after that 1402 * destroy it in the context of init_net. 1403 */ 1404 void sk_release_kernel(struct sock *sk) 1405 { 1406 if (sk == NULL || sk->sk_socket == NULL) 1407 return; 1408 1409 sock_hold(sk); 1410 sock_release(sk->sk_socket); 1411 release_net(sock_net(sk)); 1412 sock_net_set(sk, get_net(&init_net)); 1413 sock_put(sk); 1414 } 1415 EXPORT_SYMBOL(sk_release_kernel); 1416 1417 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1418 { 1419 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1420 sock_update_memcg(newsk); 1421 } 1422 1423 /** 1424 * sk_clone_lock - clone a socket, and lock its clone 1425 * @sk: the socket to clone 1426 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1427 * 1428 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1429 */ 1430 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1431 { 1432 struct sock *newsk; 1433 1434 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1435 if (newsk != NULL) { 1436 struct sk_filter *filter; 1437 1438 sock_copy(newsk, sk); 1439 1440 /* SANITY */ 1441 get_net(sock_net(newsk)); 1442 sk_node_init(&newsk->sk_node); 1443 sock_lock_init(newsk); 1444 bh_lock_sock(newsk); 1445 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1446 newsk->sk_backlog.len = 0; 1447 1448 atomic_set(&newsk->sk_rmem_alloc, 0); 1449 /* 1450 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1451 */ 1452 atomic_set(&newsk->sk_wmem_alloc, 1); 1453 atomic_set(&newsk->sk_omem_alloc, 0); 1454 skb_queue_head_init(&newsk->sk_receive_queue); 1455 skb_queue_head_init(&newsk->sk_write_queue); 1456 #ifdef CONFIG_NET_DMA 1457 skb_queue_head_init(&newsk->sk_async_wait_queue); 1458 #endif 1459 1460 spin_lock_init(&newsk->sk_dst_lock); 1461 rwlock_init(&newsk->sk_callback_lock); 1462 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1463 af_callback_keys + newsk->sk_family, 1464 af_family_clock_key_strings[newsk->sk_family]); 1465 1466 newsk->sk_dst_cache = NULL; 1467 newsk->sk_wmem_queued = 0; 1468 newsk->sk_forward_alloc = 0; 1469 newsk->sk_send_head = NULL; 1470 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1471 1472 sock_reset_flag(newsk, SOCK_DONE); 1473 skb_queue_head_init(&newsk->sk_error_queue); 1474 1475 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1476 if (filter != NULL) 1477 sk_filter_charge(newsk, filter); 1478 1479 if (unlikely(xfrm_sk_clone_policy(newsk))) { 1480 /* It is still raw copy of parent, so invalidate 1481 * destructor and make plain sk_free() */ 1482 newsk->sk_destruct = NULL; 1483 bh_unlock_sock(newsk); 1484 sk_free(newsk); 1485 newsk = NULL; 1486 goto out; 1487 } 1488 1489 newsk->sk_err = 0; 1490 newsk->sk_priority = 0; 1491 /* 1492 * Before updating sk_refcnt, we must commit prior changes to memory 1493 * (Documentation/RCU/rculist_nulls.txt for details) 1494 */ 1495 smp_wmb(); 1496 atomic_set(&newsk->sk_refcnt, 2); 1497 1498 /* 1499 * Increment the counter in the same struct proto as the master 1500 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1501 * is the same as sk->sk_prot->socks, as this field was copied 1502 * with memcpy). 1503 * 1504 * This _changes_ the previous behaviour, where 1505 * tcp_create_openreq_child always was incrementing the 1506 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1507 * to be taken into account in all callers. -acme 1508 */ 1509 sk_refcnt_debug_inc(newsk); 1510 sk_set_socket(newsk, NULL); 1511 newsk->sk_wq = NULL; 1512 1513 sk_update_clone(sk, newsk); 1514 1515 if (newsk->sk_prot->sockets_allocated) 1516 sk_sockets_allocated_inc(newsk); 1517 1518 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1519 net_enable_timestamp(); 1520 } 1521 out: 1522 return newsk; 1523 } 1524 EXPORT_SYMBOL_GPL(sk_clone_lock); 1525 1526 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1527 { 1528 __sk_dst_set(sk, dst); 1529 sk->sk_route_caps = dst->dev->features; 1530 if (sk->sk_route_caps & NETIF_F_GSO) 1531 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1532 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1533 if (sk_can_gso(sk)) { 1534 if (dst->header_len) { 1535 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1536 } else { 1537 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1538 sk->sk_gso_max_size = dst->dev->gso_max_size; 1539 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1540 } 1541 } 1542 } 1543 EXPORT_SYMBOL_GPL(sk_setup_caps); 1544 1545 /* 1546 * Simple resource managers for sockets. 1547 */ 1548 1549 1550 /* 1551 * Write buffer destructor automatically called from kfree_skb. 1552 */ 1553 void sock_wfree(struct sk_buff *skb) 1554 { 1555 struct sock *sk = skb->sk; 1556 unsigned int len = skb->truesize; 1557 1558 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1559 /* 1560 * Keep a reference on sk_wmem_alloc, this will be released 1561 * after sk_write_space() call 1562 */ 1563 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1564 sk->sk_write_space(sk); 1565 len = 1; 1566 } 1567 /* 1568 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1569 * could not do because of in-flight packets 1570 */ 1571 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1572 __sk_free(sk); 1573 } 1574 EXPORT_SYMBOL(sock_wfree); 1575 1576 /* 1577 * Read buffer destructor automatically called from kfree_skb. 1578 */ 1579 void sock_rfree(struct sk_buff *skb) 1580 { 1581 struct sock *sk = skb->sk; 1582 unsigned int len = skb->truesize; 1583 1584 atomic_sub(len, &sk->sk_rmem_alloc); 1585 sk_mem_uncharge(sk, len); 1586 } 1587 EXPORT_SYMBOL(sock_rfree); 1588 1589 void sock_edemux(struct sk_buff *skb) 1590 { 1591 struct sock *sk = skb->sk; 1592 1593 #ifdef CONFIG_INET 1594 if (sk->sk_state == TCP_TIME_WAIT) 1595 inet_twsk_put(inet_twsk(sk)); 1596 else 1597 #endif 1598 sock_put(sk); 1599 } 1600 EXPORT_SYMBOL(sock_edemux); 1601 1602 kuid_t sock_i_uid(struct sock *sk) 1603 { 1604 kuid_t uid; 1605 1606 read_lock_bh(&sk->sk_callback_lock); 1607 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1608 read_unlock_bh(&sk->sk_callback_lock); 1609 return uid; 1610 } 1611 EXPORT_SYMBOL(sock_i_uid); 1612 1613 unsigned long sock_i_ino(struct sock *sk) 1614 { 1615 unsigned long ino; 1616 1617 read_lock_bh(&sk->sk_callback_lock); 1618 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1619 read_unlock_bh(&sk->sk_callback_lock); 1620 return ino; 1621 } 1622 EXPORT_SYMBOL(sock_i_ino); 1623 1624 /* 1625 * Allocate a skb from the socket's send buffer. 1626 */ 1627 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1628 gfp_t priority) 1629 { 1630 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1631 struct sk_buff *skb = alloc_skb(size, priority); 1632 if (skb) { 1633 skb_set_owner_w(skb, sk); 1634 return skb; 1635 } 1636 } 1637 return NULL; 1638 } 1639 EXPORT_SYMBOL(sock_wmalloc); 1640 1641 /* 1642 * Allocate a skb from the socket's receive buffer. 1643 */ 1644 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, 1645 gfp_t priority) 1646 { 1647 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1648 struct sk_buff *skb = alloc_skb(size, priority); 1649 if (skb) { 1650 skb_set_owner_r(skb, sk); 1651 return skb; 1652 } 1653 } 1654 return NULL; 1655 } 1656 1657 /* 1658 * Allocate a memory block from the socket's option memory buffer. 1659 */ 1660 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1661 { 1662 if ((unsigned int)size <= sysctl_optmem_max && 1663 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1664 void *mem; 1665 /* First do the add, to avoid the race if kmalloc 1666 * might sleep. 1667 */ 1668 atomic_add(size, &sk->sk_omem_alloc); 1669 mem = kmalloc(size, priority); 1670 if (mem) 1671 return mem; 1672 atomic_sub(size, &sk->sk_omem_alloc); 1673 } 1674 return NULL; 1675 } 1676 EXPORT_SYMBOL(sock_kmalloc); 1677 1678 /* 1679 * Free an option memory block. 1680 */ 1681 void sock_kfree_s(struct sock *sk, void *mem, int size) 1682 { 1683 kfree(mem); 1684 atomic_sub(size, &sk->sk_omem_alloc); 1685 } 1686 EXPORT_SYMBOL(sock_kfree_s); 1687 1688 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1689 I think, these locks should be removed for datagram sockets. 1690 */ 1691 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1692 { 1693 DEFINE_WAIT(wait); 1694 1695 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1696 for (;;) { 1697 if (!timeo) 1698 break; 1699 if (signal_pending(current)) 1700 break; 1701 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1702 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1703 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1704 break; 1705 if (sk->sk_shutdown & SEND_SHUTDOWN) 1706 break; 1707 if (sk->sk_err) 1708 break; 1709 timeo = schedule_timeout(timeo); 1710 } 1711 finish_wait(sk_sleep(sk), &wait); 1712 return timeo; 1713 } 1714 1715 1716 /* 1717 * Generic send/receive buffer handlers 1718 */ 1719 1720 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1721 unsigned long data_len, int noblock, 1722 int *errcode) 1723 { 1724 struct sk_buff *skb; 1725 gfp_t gfp_mask; 1726 long timeo; 1727 int err; 1728 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1729 1730 err = -EMSGSIZE; 1731 if (npages > MAX_SKB_FRAGS) 1732 goto failure; 1733 1734 gfp_mask = sk->sk_allocation; 1735 if (gfp_mask & __GFP_WAIT) 1736 gfp_mask |= __GFP_REPEAT; 1737 1738 timeo = sock_sndtimeo(sk, noblock); 1739 while (1) { 1740 err = sock_error(sk); 1741 if (err != 0) 1742 goto failure; 1743 1744 err = -EPIPE; 1745 if (sk->sk_shutdown & SEND_SHUTDOWN) 1746 goto failure; 1747 1748 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1749 skb = alloc_skb(header_len, gfp_mask); 1750 if (skb) { 1751 int i; 1752 1753 /* No pages, we're done... */ 1754 if (!data_len) 1755 break; 1756 1757 skb->truesize += data_len; 1758 skb_shinfo(skb)->nr_frags = npages; 1759 for (i = 0; i < npages; i++) { 1760 struct page *page; 1761 1762 page = alloc_pages(sk->sk_allocation, 0); 1763 if (!page) { 1764 err = -ENOBUFS; 1765 skb_shinfo(skb)->nr_frags = i; 1766 kfree_skb(skb); 1767 goto failure; 1768 } 1769 1770 __skb_fill_page_desc(skb, i, 1771 page, 0, 1772 (data_len >= PAGE_SIZE ? 1773 PAGE_SIZE : 1774 data_len)); 1775 data_len -= PAGE_SIZE; 1776 } 1777 1778 /* Full success... */ 1779 break; 1780 } 1781 err = -ENOBUFS; 1782 goto failure; 1783 } 1784 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1785 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1786 err = -EAGAIN; 1787 if (!timeo) 1788 goto failure; 1789 if (signal_pending(current)) 1790 goto interrupted; 1791 timeo = sock_wait_for_wmem(sk, timeo); 1792 } 1793 1794 skb_set_owner_w(skb, sk); 1795 return skb; 1796 1797 interrupted: 1798 err = sock_intr_errno(timeo); 1799 failure: 1800 *errcode = err; 1801 return NULL; 1802 } 1803 EXPORT_SYMBOL(sock_alloc_send_pskb); 1804 1805 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1806 int noblock, int *errcode) 1807 { 1808 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode); 1809 } 1810 EXPORT_SYMBOL(sock_alloc_send_skb); 1811 1812 /* On 32bit arches, an skb frag is limited to 2^15 */ 1813 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1814 1815 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1816 { 1817 int order; 1818 1819 if (pfrag->page) { 1820 if (atomic_read(&pfrag->page->_count) == 1) { 1821 pfrag->offset = 0; 1822 return true; 1823 } 1824 if (pfrag->offset < pfrag->size) 1825 return true; 1826 put_page(pfrag->page); 1827 } 1828 1829 /* We restrict high order allocations to users that can afford to wait */ 1830 order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0; 1831 1832 do { 1833 gfp_t gfp = sk->sk_allocation; 1834 1835 if (order) 1836 gfp |= __GFP_COMP | __GFP_NOWARN; 1837 pfrag->page = alloc_pages(gfp, order); 1838 if (likely(pfrag->page)) { 1839 pfrag->offset = 0; 1840 pfrag->size = PAGE_SIZE << order; 1841 return true; 1842 } 1843 } while (--order >= 0); 1844 1845 sk_enter_memory_pressure(sk); 1846 sk_stream_moderate_sndbuf(sk); 1847 return false; 1848 } 1849 EXPORT_SYMBOL(sk_page_frag_refill); 1850 1851 static void __lock_sock(struct sock *sk) 1852 __releases(&sk->sk_lock.slock) 1853 __acquires(&sk->sk_lock.slock) 1854 { 1855 DEFINE_WAIT(wait); 1856 1857 for (;;) { 1858 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1859 TASK_UNINTERRUPTIBLE); 1860 spin_unlock_bh(&sk->sk_lock.slock); 1861 schedule(); 1862 spin_lock_bh(&sk->sk_lock.slock); 1863 if (!sock_owned_by_user(sk)) 1864 break; 1865 } 1866 finish_wait(&sk->sk_lock.wq, &wait); 1867 } 1868 1869 static void __release_sock(struct sock *sk) 1870 __releases(&sk->sk_lock.slock) 1871 __acquires(&sk->sk_lock.slock) 1872 { 1873 struct sk_buff *skb = sk->sk_backlog.head; 1874 1875 do { 1876 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1877 bh_unlock_sock(sk); 1878 1879 do { 1880 struct sk_buff *next = skb->next; 1881 1882 prefetch(next); 1883 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1884 skb->next = NULL; 1885 sk_backlog_rcv(sk, skb); 1886 1887 /* 1888 * We are in process context here with softirqs 1889 * disabled, use cond_resched_softirq() to preempt. 1890 * This is safe to do because we've taken the backlog 1891 * queue private: 1892 */ 1893 cond_resched_softirq(); 1894 1895 skb = next; 1896 } while (skb != NULL); 1897 1898 bh_lock_sock(sk); 1899 } while ((skb = sk->sk_backlog.head) != NULL); 1900 1901 /* 1902 * Doing the zeroing here guarantee we can not loop forever 1903 * while a wild producer attempts to flood us. 1904 */ 1905 sk->sk_backlog.len = 0; 1906 } 1907 1908 /** 1909 * sk_wait_data - wait for data to arrive at sk_receive_queue 1910 * @sk: sock to wait on 1911 * @timeo: for how long 1912 * 1913 * Now socket state including sk->sk_err is changed only under lock, 1914 * hence we may omit checks after joining wait queue. 1915 * We check receive queue before schedule() only as optimization; 1916 * it is very likely that release_sock() added new data. 1917 */ 1918 int sk_wait_data(struct sock *sk, long *timeo) 1919 { 1920 int rc; 1921 DEFINE_WAIT(wait); 1922 1923 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1924 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1925 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1926 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1927 finish_wait(sk_sleep(sk), &wait); 1928 return rc; 1929 } 1930 EXPORT_SYMBOL(sk_wait_data); 1931 1932 /** 1933 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1934 * @sk: socket 1935 * @size: memory size to allocate 1936 * @kind: allocation type 1937 * 1938 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1939 * rmem allocation. This function assumes that protocols which have 1940 * memory_pressure use sk_wmem_queued as write buffer accounting. 1941 */ 1942 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1943 { 1944 struct proto *prot = sk->sk_prot; 1945 int amt = sk_mem_pages(size); 1946 long allocated; 1947 int parent_status = UNDER_LIMIT; 1948 1949 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1950 1951 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 1952 1953 /* Under limit. */ 1954 if (parent_status == UNDER_LIMIT && 1955 allocated <= sk_prot_mem_limits(sk, 0)) { 1956 sk_leave_memory_pressure(sk); 1957 return 1; 1958 } 1959 1960 /* Under pressure. (we or our parents) */ 1961 if ((parent_status > SOFT_LIMIT) || 1962 allocated > sk_prot_mem_limits(sk, 1)) 1963 sk_enter_memory_pressure(sk); 1964 1965 /* Over hard limit (we or our parents) */ 1966 if ((parent_status == OVER_LIMIT) || 1967 (allocated > sk_prot_mem_limits(sk, 2))) 1968 goto suppress_allocation; 1969 1970 /* guarantee minimum buffer size under pressure */ 1971 if (kind == SK_MEM_RECV) { 1972 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 1973 return 1; 1974 1975 } else { /* SK_MEM_SEND */ 1976 if (sk->sk_type == SOCK_STREAM) { 1977 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 1978 return 1; 1979 } else if (atomic_read(&sk->sk_wmem_alloc) < 1980 prot->sysctl_wmem[0]) 1981 return 1; 1982 } 1983 1984 if (sk_has_memory_pressure(sk)) { 1985 int alloc; 1986 1987 if (!sk_under_memory_pressure(sk)) 1988 return 1; 1989 alloc = sk_sockets_allocated_read_positive(sk); 1990 if (sk_prot_mem_limits(sk, 2) > alloc * 1991 sk_mem_pages(sk->sk_wmem_queued + 1992 atomic_read(&sk->sk_rmem_alloc) + 1993 sk->sk_forward_alloc)) 1994 return 1; 1995 } 1996 1997 suppress_allocation: 1998 1999 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2000 sk_stream_moderate_sndbuf(sk); 2001 2002 /* Fail only if socket is _under_ its sndbuf. 2003 * In this case we cannot block, so that we have to fail. 2004 */ 2005 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2006 return 1; 2007 } 2008 2009 trace_sock_exceed_buf_limit(sk, prot, allocated); 2010 2011 /* Alas. Undo changes. */ 2012 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2013 2014 sk_memory_allocated_sub(sk, amt); 2015 2016 return 0; 2017 } 2018 EXPORT_SYMBOL(__sk_mem_schedule); 2019 2020 /** 2021 * __sk_reclaim - reclaim memory_allocated 2022 * @sk: socket 2023 */ 2024 void __sk_mem_reclaim(struct sock *sk) 2025 { 2026 sk_memory_allocated_sub(sk, 2027 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2028 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2029 2030 if (sk_under_memory_pressure(sk) && 2031 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2032 sk_leave_memory_pressure(sk); 2033 } 2034 EXPORT_SYMBOL(__sk_mem_reclaim); 2035 2036 2037 /* 2038 * Set of default routines for initialising struct proto_ops when 2039 * the protocol does not support a particular function. In certain 2040 * cases where it makes no sense for a protocol to have a "do nothing" 2041 * function, some default processing is provided. 2042 */ 2043 2044 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2045 { 2046 return -EOPNOTSUPP; 2047 } 2048 EXPORT_SYMBOL(sock_no_bind); 2049 2050 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2051 int len, int flags) 2052 { 2053 return -EOPNOTSUPP; 2054 } 2055 EXPORT_SYMBOL(sock_no_connect); 2056 2057 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2058 { 2059 return -EOPNOTSUPP; 2060 } 2061 EXPORT_SYMBOL(sock_no_socketpair); 2062 2063 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2064 { 2065 return -EOPNOTSUPP; 2066 } 2067 EXPORT_SYMBOL(sock_no_accept); 2068 2069 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2070 int *len, int peer) 2071 { 2072 return -EOPNOTSUPP; 2073 } 2074 EXPORT_SYMBOL(sock_no_getname); 2075 2076 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2077 { 2078 return 0; 2079 } 2080 EXPORT_SYMBOL(sock_no_poll); 2081 2082 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2083 { 2084 return -EOPNOTSUPP; 2085 } 2086 EXPORT_SYMBOL(sock_no_ioctl); 2087 2088 int sock_no_listen(struct socket *sock, int backlog) 2089 { 2090 return -EOPNOTSUPP; 2091 } 2092 EXPORT_SYMBOL(sock_no_listen); 2093 2094 int sock_no_shutdown(struct socket *sock, int how) 2095 { 2096 return -EOPNOTSUPP; 2097 } 2098 EXPORT_SYMBOL(sock_no_shutdown); 2099 2100 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2101 char __user *optval, unsigned int optlen) 2102 { 2103 return -EOPNOTSUPP; 2104 } 2105 EXPORT_SYMBOL(sock_no_setsockopt); 2106 2107 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2108 char __user *optval, int __user *optlen) 2109 { 2110 return -EOPNOTSUPP; 2111 } 2112 EXPORT_SYMBOL(sock_no_getsockopt); 2113 2114 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2115 size_t len) 2116 { 2117 return -EOPNOTSUPP; 2118 } 2119 EXPORT_SYMBOL(sock_no_sendmsg); 2120 2121 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2122 size_t len, int flags) 2123 { 2124 return -EOPNOTSUPP; 2125 } 2126 EXPORT_SYMBOL(sock_no_recvmsg); 2127 2128 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2129 { 2130 /* Mirror missing mmap method error code */ 2131 return -ENODEV; 2132 } 2133 EXPORT_SYMBOL(sock_no_mmap); 2134 2135 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2136 { 2137 ssize_t res; 2138 struct msghdr msg = {.msg_flags = flags}; 2139 struct kvec iov; 2140 char *kaddr = kmap(page); 2141 iov.iov_base = kaddr + offset; 2142 iov.iov_len = size; 2143 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2144 kunmap(page); 2145 return res; 2146 } 2147 EXPORT_SYMBOL(sock_no_sendpage); 2148 2149 /* 2150 * Default Socket Callbacks 2151 */ 2152 2153 static void sock_def_wakeup(struct sock *sk) 2154 { 2155 struct socket_wq *wq; 2156 2157 rcu_read_lock(); 2158 wq = rcu_dereference(sk->sk_wq); 2159 if (wq_has_sleeper(wq)) 2160 wake_up_interruptible_all(&wq->wait); 2161 rcu_read_unlock(); 2162 } 2163 2164 static void sock_def_error_report(struct sock *sk) 2165 { 2166 struct socket_wq *wq; 2167 2168 rcu_read_lock(); 2169 wq = rcu_dereference(sk->sk_wq); 2170 if (wq_has_sleeper(wq)) 2171 wake_up_interruptible_poll(&wq->wait, POLLERR); 2172 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2173 rcu_read_unlock(); 2174 } 2175 2176 static void sock_def_readable(struct sock *sk, int len) 2177 { 2178 struct socket_wq *wq; 2179 2180 rcu_read_lock(); 2181 wq = rcu_dereference(sk->sk_wq); 2182 if (wq_has_sleeper(wq)) 2183 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2184 POLLRDNORM | POLLRDBAND); 2185 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2186 rcu_read_unlock(); 2187 } 2188 2189 static void sock_def_write_space(struct sock *sk) 2190 { 2191 struct socket_wq *wq; 2192 2193 rcu_read_lock(); 2194 2195 /* Do not wake up a writer until he can make "significant" 2196 * progress. --DaveM 2197 */ 2198 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2199 wq = rcu_dereference(sk->sk_wq); 2200 if (wq_has_sleeper(wq)) 2201 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2202 POLLWRNORM | POLLWRBAND); 2203 2204 /* Should agree with poll, otherwise some programs break */ 2205 if (sock_writeable(sk)) 2206 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2207 } 2208 2209 rcu_read_unlock(); 2210 } 2211 2212 static void sock_def_destruct(struct sock *sk) 2213 { 2214 kfree(sk->sk_protinfo); 2215 } 2216 2217 void sk_send_sigurg(struct sock *sk) 2218 { 2219 if (sk->sk_socket && sk->sk_socket->file) 2220 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2221 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2222 } 2223 EXPORT_SYMBOL(sk_send_sigurg); 2224 2225 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2226 unsigned long expires) 2227 { 2228 if (!mod_timer(timer, expires)) 2229 sock_hold(sk); 2230 } 2231 EXPORT_SYMBOL(sk_reset_timer); 2232 2233 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2234 { 2235 if (del_timer(timer)) 2236 __sock_put(sk); 2237 } 2238 EXPORT_SYMBOL(sk_stop_timer); 2239 2240 void sock_init_data(struct socket *sock, struct sock *sk) 2241 { 2242 skb_queue_head_init(&sk->sk_receive_queue); 2243 skb_queue_head_init(&sk->sk_write_queue); 2244 skb_queue_head_init(&sk->sk_error_queue); 2245 #ifdef CONFIG_NET_DMA 2246 skb_queue_head_init(&sk->sk_async_wait_queue); 2247 #endif 2248 2249 sk->sk_send_head = NULL; 2250 2251 init_timer(&sk->sk_timer); 2252 2253 sk->sk_allocation = GFP_KERNEL; 2254 sk->sk_rcvbuf = sysctl_rmem_default; 2255 sk->sk_sndbuf = sysctl_wmem_default; 2256 sk->sk_state = TCP_CLOSE; 2257 sk_set_socket(sk, sock); 2258 2259 sock_set_flag(sk, SOCK_ZAPPED); 2260 2261 if (sock) { 2262 sk->sk_type = sock->type; 2263 sk->sk_wq = sock->wq; 2264 sock->sk = sk; 2265 } else 2266 sk->sk_wq = NULL; 2267 2268 spin_lock_init(&sk->sk_dst_lock); 2269 rwlock_init(&sk->sk_callback_lock); 2270 lockdep_set_class_and_name(&sk->sk_callback_lock, 2271 af_callback_keys + sk->sk_family, 2272 af_family_clock_key_strings[sk->sk_family]); 2273 2274 sk->sk_state_change = sock_def_wakeup; 2275 sk->sk_data_ready = sock_def_readable; 2276 sk->sk_write_space = sock_def_write_space; 2277 sk->sk_error_report = sock_def_error_report; 2278 sk->sk_destruct = sock_def_destruct; 2279 2280 sk->sk_frag.page = NULL; 2281 sk->sk_frag.offset = 0; 2282 sk->sk_peek_off = -1; 2283 2284 sk->sk_peer_pid = NULL; 2285 sk->sk_peer_cred = NULL; 2286 sk->sk_write_pending = 0; 2287 sk->sk_rcvlowat = 1; 2288 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2289 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2290 2291 sk->sk_stamp = ktime_set(-1L, 0); 2292 2293 /* 2294 * Before updating sk_refcnt, we must commit prior changes to memory 2295 * (Documentation/RCU/rculist_nulls.txt for details) 2296 */ 2297 smp_wmb(); 2298 atomic_set(&sk->sk_refcnt, 1); 2299 atomic_set(&sk->sk_drops, 0); 2300 } 2301 EXPORT_SYMBOL(sock_init_data); 2302 2303 void lock_sock_nested(struct sock *sk, int subclass) 2304 { 2305 might_sleep(); 2306 spin_lock_bh(&sk->sk_lock.slock); 2307 if (sk->sk_lock.owned) 2308 __lock_sock(sk); 2309 sk->sk_lock.owned = 1; 2310 spin_unlock(&sk->sk_lock.slock); 2311 /* 2312 * The sk_lock has mutex_lock() semantics here: 2313 */ 2314 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2315 local_bh_enable(); 2316 } 2317 EXPORT_SYMBOL(lock_sock_nested); 2318 2319 void release_sock(struct sock *sk) 2320 { 2321 /* 2322 * The sk_lock has mutex_unlock() semantics: 2323 */ 2324 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2325 2326 spin_lock_bh(&sk->sk_lock.slock); 2327 if (sk->sk_backlog.tail) 2328 __release_sock(sk); 2329 2330 if (sk->sk_prot->release_cb) 2331 sk->sk_prot->release_cb(sk); 2332 2333 sk->sk_lock.owned = 0; 2334 if (waitqueue_active(&sk->sk_lock.wq)) 2335 wake_up(&sk->sk_lock.wq); 2336 spin_unlock_bh(&sk->sk_lock.slock); 2337 } 2338 EXPORT_SYMBOL(release_sock); 2339 2340 /** 2341 * lock_sock_fast - fast version of lock_sock 2342 * @sk: socket 2343 * 2344 * This version should be used for very small section, where process wont block 2345 * return false if fast path is taken 2346 * sk_lock.slock locked, owned = 0, BH disabled 2347 * return true if slow path is taken 2348 * sk_lock.slock unlocked, owned = 1, BH enabled 2349 */ 2350 bool lock_sock_fast(struct sock *sk) 2351 { 2352 might_sleep(); 2353 spin_lock_bh(&sk->sk_lock.slock); 2354 2355 if (!sk->sk_lock.owned) 2356 /* 2357 * Note : We must disable BH 2358 */ 2359 return false; 2360 2361 __lock_sock(sk); 2362 sk->sk_lock.owned = 1; 2363 spin_unlock(&sk->sk_lock.slock); 2364 /* 2365 * The sk_lock has mutex_lock() semantics here: 2366 */ 2367 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2368 local_bh_enable(); 2369 return true; 2370 } 2371 EXPORT_SYMBOL(lock_sock_fast); 2372 2373 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2374 { 2375 struct timeval tv; 2376 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2377 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2378 tv = ktime_to_timeval(sk->sk_stamp); 2379 if (tv.tv_sec == -1) 2380 return -ENOENT; 2381 if (tv.tv_sec == 0) { 2382 sk->sk_stamp = ktime_get_real(); 2383 tv = ktime_to_timeval(sk->sk_stamp); 2384 } 2385 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2386 } 2387 EXPORT_SYMBOL(sock_get_timestamp); 2388 2389 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2390 { 2391 struct timespec ts; 2392 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2393 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2394 ts = ktime_to_timespec(sk->sk_stamp); 2395 if (ts.tv_sec == -1) 2396 return -ENOENT; 2397 if (ts.tv_sec == 0) { 2398 sk->sk_stamp = ktime_get_real(); 2399 ts = ktime_to_timespec(sk->sk_stamp); 2400 } 2401 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2402 } 2403 EXPORT_SYMBOL(sock_get_timestampns); 2404 2405 void sock_enable_timestamp(struct sock *sk, int flag) 2406 { 2407 if (!sock_flag(sk, flag)) { 2408 unsigned long previous_flags = sk->sk_flags; 2409 2410 sock_set_flag(sk, flag); 2411 /* 2412 * we just set one of the two flags which require net 2413 * time stamping, but time stamping might have been on 2414 * already because of the other one 2415 */ 2416 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2417 net_enable_timestamp(); 2418 } 2419 } 2420 2421 /* 2422 * Get a socket option on an socket. 2423 * 2424 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2425 * asynchronous errors should be reported by getsockopt. We assume 2426 * this means if you specify SO_ERROR (otherwise whats the point of it). 2427 */ 2428 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2429 char __user *optval, int __user *optlen) 2430 { 2431 struct sock *sk = sock->sk; 2432 2433 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2434 } 2435 EXPORT_SYMBOL(sock_common_getsockopt); 2436 2437 #ifdef CONFIG_COMPAT 2438 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2439 char __user *optval, int __user *optlen) 2440 { 2441 struct sock *sk = sock->sk; 2442 2443 if (sk->sk_prot->compat_getsockopt != NULL) 2444 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2445 optval, optlen); 2446 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2447 } 2448 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2449 #endif 2450 2451 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2452 struct msghdr *msg, size_t size, int flags) 2453 { 2454 struct sock *sk = sock->sk; 2455 int addr_len = 0; 2456 int err; 2457 2458 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2459 flags & ~MSG_DONTWAIT, &addr_len); 2460 if (err >= 0) 2461 msg->msg_namelen = addr_len; 2462 return err; 2463 } 2464 EXPORT_SYMBOL(sock_common_recvmsg); 2465 2466 /* 2467 * Set socket options on an inet socket. 2468 */ 2469 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2470 char __user *optval, unsigned int optlen) 2471 { 2472 struct sock *sk = sock->sk; 2473 2474 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2475 } 2476 EXPORT_SYMBOL(sock_common_setsockopt); 2477 2478 #ifdef CONFIG_COMPAT 2479 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2480 char __user *optval, unsigned int optlen) 2481 { 2482 struct sock *sk = sock->sk; 2483 2484 if (sk->sk_prot->compat_setsockopt != NULL) 2485 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2486 optval, optlen); 2487 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2488 } 2489 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2490 #endif 2491 2492 void sk_common_release(struct sock *sk) 2493 { 2494 if (sk->sk_prot->destroy) 2495 sk->sk_prot->destroy(sk); 2496 2497 /* 2498 * Observation: when sock_common_release is called, processes have 2499 * no access to socket. But net still has. 2500 * Step one, detach it from networking: 2501 * 2502 * A. Remove from hash tables. 2503 */ 2504 2505 sk->sk_prot->unhash(sk); 2506 2507 /* 2508 * In this point socket cannot receive new packets, but it is possible 2509 * that some packets are in flight because some CPU runs receiver and 2510 * did hash table lookup before we unhashed socket. They will achieve 2511 * receive queue and will be purged by socket destructor. 2512 * 2513 * Also we still have packets pending on receive queue and probably, 2514 * our own packets waiting in device queues. sock_destroy will drain 2515 * receive queue, but transmitted packets will delay socket destruction 2516 * until the last reference will be released. 2517 */ 2518 2519 sock_orphan(sk); 2520 2521 xfrm_sk_free_policy(sk); 2522 2523 sk_refcnt_debug_release(sk); 2524 2525 if (sk->sk_frag.page) { 2526 put_page(sk->sk_frag.page); 2527 sk->sk_frag.page = NULL; 2528 } 2529 2530 sock_put(sk); 2531 } 2532 EXPORT_SYMBOL(sk_common_release); 2533 2534 #ifdef CONFIG_PROC_FS 2535 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2536 struct prot_inuse { 2537 int val[PROTO_INUSE_NR]; 2538 }; 2539 2540 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2541 2542 #ifdef CONFIG_NET_NS 2543 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2544 { 2545 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2546 } 2547 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2548 2549 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2550 { 2551 int cpu, idx = prot->inuse_idx; 2552 int res = 0; 2553 2554 for_each_possible_cpu(cpu) 2555 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2556 2557 return res >= 0 ? res : 0; 2558 } 2559 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2560 2561 static int __net_init sock_inuse_init_net(struct net *net) 2562 { 2563 net->core.inuse = alloc_percpu(struct prot_inuse); 2564 return net->core.inuse ? 0 : -ENOMEM; 2565 } 2566 2567 static void __net_exit sock_inuse_exit_net(struct net *net) 2568 { 2569 free_percpu(net->core.inuse); 2570 } 2571 2572 static struct pernet_operations net_inuse_ops = { 2573 .init = sock_inuse_init_net, 2574 .exit = sock_inuse_exit_net, 2575 }; 2576 2577 static __init int net_inuse_init(void) 2578 { 2579 if (register_pernet_subsys(&net_inuse_ops)) 2580 panic("Cannot initialize net inuse counters"); 2581 2582 return 0; 2583 } 2584 2585 core_initcall(net_inuse_init); 2586 #else 2587 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2588 2589 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2590 { 2591 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2592 } 2593 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2594 2595 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2596 { 2597 int cpu, idx = prot->inuse_idx; 2598 int res = 0; 2599 2600 for_each_possible_cpu(cpu) 2601 res += per_cpu(prot_inuse, cpu).val[idx]; 2602 2603 return res >= 0 ? res : 0; 2604 } 2605 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2606 #endif 2607 2608 static void assign_proto_idx(struct proto *prot) 2609 { 2610 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2611 2612 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2613 pr_err("PROTO_INUSE_NR exhausted\n"); 2614 return; 2615 } 2616 2617 set_bit(prot->inuse_idx, proto_inuse_idx); 2618 } 2619 2620 static void release_proto_idx(struct proto *prot) 2621 { 2622 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2623 clear_bit(prot->inuse_idx, proto_inuse_idx); 2624 } 2625 #else 2626 static inline void assign_proto_idx(struct proto *prot) 2627 { 2628 } 2629 2630 static inline void release_proto_idx(struct proto *prot) 2631 { 2632 } 2633 #endif 2634 2635 int proto_register(struct proto *prot, int alloc_slab) 2636 { 2637 if (alloc_slab) { 2638 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2639 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2640 NULL); 2641 2642 if (prot->slab == NULL) { 2643 pr_crit("%s: Can't create sock SLAB cache!\n", 2644 prot->name); 2645 goto out; 2646 } 2647 2648 if (prot->rsk_prot != NULL) { 2649 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2650 if (prot->rsk_prot->slab_name == NULL) 2651 goto out_free_sock_slab; 2652 2653 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2654 prot->rsk_prot->obj_size, 0, 2655 SLAB_HWCACHE_ALIGN, NULL); 2656 2657 if (prot->rsk_prot->slab == NULL) { 2658 pr_crit("%s: Can't create request sock SLAB cache!\n", 2659 prot->name); 2660 goto out_free_request_sock_slab_name; 2661 } 2662 } 2663 2664 if (prot->twsk_prot != NULL) { 2665 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2666 2667 if (prot->twsk_prot->twsk_slab_name == NULL) 2668 goto out_free_request_sock_slab; 2669 2670 prot->twsk_prot->twsk_slab = 2671 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2672 prot->twsk_prot->twsk_obj_size, 2673 0, 2674 SLAB_HWCACHE_ALIGN | 2675 prot->slab_flags, 2676 NULL); 2677 if (prot->twsk_prot->twsk_slab == NULL) 2678 goto out_free_timewait_sock_slab_name; 2679 } 2680 } 2681 2682 mutex_lock(&proto_list_mutex); 2683 list_add(&prot->node, &proto_list); 2684 assign_proto_idx(prot); 2685 mutex_unlock(&proto_list_mutex); 2686 return 0; 2687 2688 out_free_timewait_sock_slab_name: 2689 kfree(prot->twsk_prot->twsk_slab_name); 2690 out_free_request_sock_slab: 2691 if (prot->rsk_prot && prot->rsk_prot->slab) { 2692 kmem_cache_destroy(prot->rsk_prot->slab); 2693 prot->rsk_prot->slab = NULL; 2694 } 2695 out_free_request_sock_slab_name: 2696 if (prot->rsk_prot) 2697 kfree(prot->rsk_prot->slab_name); 2698 out_free_sock_slab: 2699 kmem_cache_destroy(prot->slab); 2700 prot->slab = NULL; 2701 out: 2702 return -ENOBUFS; 2703 } 2704 EXPORT_SYMBOL(proto_register); 2705 2706 void proto_unregister(struct proto *prot) 2707 { 2708 mutex_lock(&proto_list_mutex); 2709 release_proto_idx(prot); 2710 list_del(&prot->node); 2711 mutex_unlock(&proto_list_mutex); 2712 2713 if (prot->slab != NULL) { 2714 kmem_cache_destroy(prot->slab); 2715 prot->slab = NULL; 2716 } 2717 2718 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2719 kmem_cache_destroy(prot->rsk_prot->slab); 2720 kfree(prot->rsk_prot->slab_name); 2721 prot->rsk_prot->slab = NULL; 2722 } 2723 2724 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2725 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2726 kfree(prot->twsk_prot->twsk_slab_name); 2727 prot->twsk_prot->twsk_slab = NULL; 2728 } 2729 } 2730 EXPORT_SYMBOL(proto_unregister); 2731 2732 #ifdef CONFIG_PROC_FS 2733 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2734 __acquires(proto_list_mutex) 2735 { 2736 mutex_lock(&proto_list_mutex); 2737 return seq_list_start_head(&proto_list, *pos); 2738 } 2739 2740 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2741 { 2742 return seq_list_next(v, &proto_list, pos); 2743 } 2744 2745 static void proto_seq_stop(struct seq_file *seq, void *v) 2746 __releases(proto_list_mutex) 2747 { 2748 mutex_unlock(&proto_list_mutex); 2749 } 2750 2751 static char proto_method_implemented(const void *method) 2752 { 2753 return method == NULL ? 'n' : 'y'; 2754 } 2755 static long sock_prot_memory_allocated(struct proto *proto) 2756 { 2757 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2758 } 2759 2760 static char *sock_prot_memory_pressure(struct proto *proto) 2761 { 2762 return proto->memory_pressure != NULL ? 2763 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2764 } 2765 2766 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2767 { 2768 2769 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2770 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2771 proto->name, 2772 proto->obj_size, 2773 sock_prot_inuse_get(seq_file_net(seq), proto), 2774 sock_prot_memory_allocated(proto), 2775 sock_prot_memory_pressure(proto), 2776 proto->max_header, 2777 proto->slab == NULL ? "no" : "yes", 2778 module_name(proto->owner), 2779 proto_method_implemented(proto->close), 2780 proto_method_implemented(proto->connect), 2781 proto_method_implemented(proto->disconnect), 2782 proto_method_implemented(proto->accept), 2783 proto_method_implemented(proto->ioctl), 2784 proto_method_implemented(proto->init), 2785 proto_method_implemented(proto->destroy), 2786 proto_method_implemented(proto->shutdown), 2787 proto_method_implemented(proto->setsockopt), 2788 proto_method_implemented(proto->getsockopt), 2789 proto_method_implemented(proto->sendmsg), 2790 proto_method_implemented(proto->recvmsg), 2791 proto_method_implemented(proto->sendpage), 2792 proto_method_implemented(proto->bind), 2793 proto_method_implemented(proto->backlog_rcv), 2794 proto_method_implemented(proto->hash), 2795 proto_method_implemented(proto->unhash), 2796 proto_method_implemented(proto->get_port), 2797 proto_method_implemented(proto->enter_memory_pressure)); 2798 } 2799 2800 static int proto_seq_show(struct seq_file *seq, void *v) 2801 { 2802 if (v == &proto_list) 2803 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2804 "protocol", 2805 "size", 2806 "sockets", 2807 "memory", 2808 "press", 2809 "maxhdr", 2810 "slab", 2811 "module", 2812 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2813 else 2814 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2815 return 0; 2816 } 2817 2818 static const struct seq_operations proto_seq_ops = { 2819 .start = proto_seq_start, 2820 .next = proto_seq_next, 2821 .stop = proto_seq_stop, 2822 .show = proto_seq_show, 2823 }; 2824 2825 static int proto_seq_open(struct inode *inode, struct file *file) 2826 { 2827 return seq_open_net(inode, file, &proto_seq_ops, 2828 sizeof(struct seq_net_private)); 2829 } 2830 2831 static const struct file_operations proto_seq_fops = { 2832 .owner = THIS_MODULE, 2833 .open = proto_seq_open, 2834 .read = seq_read, 2835 .llseek = seq_lseek, 2836 .release = seq_release_net, 2837 }; 2838 2839 static __net_init int proto_init_net(struct net *net) 2840 { 2841 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2842 return -ENOMEM; 2843 2844 return 0; 2845 } 2846 2847 static __net_exit void proto_exit_net(struct net *net) 2848 { 2849 remove_proc_entry("protocols", net->proc_net); 2850 } 2851 2852 2853 static __net_initdata struct pernet_operations proto_net_ops = { 2854 .init = proto_init_net, 2855 .exit = proto_exit_net, 2856 }; 2857 2858 static int __init proto_init(void) 2859 { 2860 return register_pernet_subsys(&proto_net_ops); 2861 } 2862 2863 subsys_initcall(proto_init); 2864 2865 #endif /* PROC_FS */ 2866