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