1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Generic socket support routines. Memory allocators, socket lock/release 7 * handler for protocols to use and generic option handler. 8 * 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Florian La Roche, <flla@stud.uni-sb.de> 13 * Alan Cox, <A.Cox@swansea.ac.uk> 14 * 15 * Fixes: 16 * Alan Cox : Numerous verify_area() problems 17 * Alan Cox : Connecting on a connecting socket 18 * now returns an error for tcp. 19 * Alan Cox : sock->protocol is set correctly. 20 * and is not sometimes left as 0. 21 * Alan Cox : connect handles icmp errors on a 22 * connect properly. Unfortunately there 23 * is a restart syscall nasty there. I 24 * can't match BSD without hacking the C 25 * library. Ideas urgently sought! 26 * Alan Cox : Disallow bind() to addresses that are 27 * not ours - especially broadcast ones!! 28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) 29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, 30 * instead they leave that for the DESTROY timer. 31 * Alan Cox : Clean up error flag in accept 32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer 33 * was buggy. Put a remove_sock() in the handler 34 * for memory when we hit 0. Also altered the timer 35 * code. The ACK stuff can wait and needs major 36 * TCP layer surgery. 37 * Alan Cox : Fixed TCP ack bug, removed remove sock 38 * and fixed timer/inet_bh race. 39 * Alan Cox : Added zapped flag for TCP 40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code 41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb 42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources 43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. 44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... 45 * Rick Sladkey : Relaxed UDP rules for matching packets. 46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support 47 * Pauline Middelink : identd support 48 * Alan Cox : Fixed connect() taking signals I think. 49 * Alan Cox : SO_LINGER supported 50 * Alan Cox : Error reporting fixes 51 * Anonymous : inet_create tidied up (sk->reuse setting) 52 * Alan Cox : inet sockets don't set sk->type! 53 * Alan Cox : Split socket option code 54 * Alan Cox : Callbacks 55 * Alan Cox : Nagle flag for Charles & Johannes stuff 56 * Alex : Removed restriction on inet fioctl 57 * Alan Cox : Splitting INET from NET core 58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() 59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code 60 * Alan Cox : Split IP from generic code 61 * Alan Cox : New kfree_skbmem() 62 * Alan Cox : Make SO_DEBUG superuser only. 63 * Alan Cox : Allow anyone to clear SO_DEBUG 64 * (compatibility fix) 65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. 66 * Alan Cox : Allocator for a socket is settable. 67 * Alan Cox : SO_ERROR includes soft errors. 68 * Alan Cox : Allow NULL arguments on some SO_ opts 69 * Alan Cox : Generic socket allocation to make hooks 70 * easier (suggested by Craig Metz). 71 * Michael Pall : SO_ERROR returns positive errno again 72 * Steve Whitehouse: Added default destructor to free 73 * protocol private data. 74 * Steve Whitehouse: Added various other default routines 75 * common to several socket families. 76 * Chris Evans : Call suser() check last on F_SETOWN 77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. 78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() 79 * Andi Kleen : Fix write_space callback 80 * Chris Evans : Security fixes - signedness again 81 * Arnaldo C. Melo : cleanups, use skb_queue_purge 82 * 83 * To Fix: 84 * 85 * 86 * This program is free software; you can redistribute it and/or 87 * modify it under the terms of the GNU General Public License 88 * as published by the Free Software Foundation; either version 89 * 2 of the License, or (at your option) any later version. 90 */ 91 92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 93 94 #include <linux/capability.h> 95 #include <linux/errno.h> 96 #include <linux/errqueue.h> 97 #include <linux/types.h> 98 #include <linux/socket.h> 99 #include <linux/in.h> 100 #include <linux/kernel.h> 101 #include <linux/module.h> 102 #include <linux/proc_fs.h> 103 #include <linux/seq_file.h> 104 #include <linux/sched.h> 105 #include <linux/timer.h> 106 #include <linux/string.h> 107 #include <linux/sockios.h> 108 #include <linux/net.h> 109 #include <linux/mm.h> 110 #include <linux/slab.h> 111 #include <linux/interrupt.h> 112 #include <linux/poll.h> 113 #include <linux/tcp.h> 114 #include <linux/init.h> 115 #include <linux/highmem.h> 116 #include <linux/user_namespace.h> 117 #include <linux/static_key.h> 118 #include <linux/memcontrol.h> 119 #include <linux/prefetch.h> 120 121 #include <asm/uaccess.h> 122 123 #include <linux/netdevice.h> 124 #include <net/protocol.h> 125 #include <linux/skbuff.h> 126 #include <net/net_namespace.h> 127 #include <net/request_sock.h> 128 #include <net/sock.h> 129 #include <linux/net_tstamp.h> 130 #include <net/xfrm.h> 131 #include <linux/ipsec.h> 132 #include <net/cls_cgroup.h> 133 #include <net/netprio_cgroup.h> 134 135 #include <linux/filter.h> 136 137 #include <trace/events/sock.h> 138 139 #ifdef CONFIG_INET 140 #include <net/tcp.h> 141 #endif 142 143 #include <net/busy_poll.h> 144 145 static DEFINE_MUTEX(proto_list_mutex); 146 static LIST_HEAD(proto_list); 147 148 /** 149 * sk_ns_capable - General socket capability test 150 * @sk: Socket to use a capability on or through 151 * @user_ns: The user namespace of the capability to use 152 * @cap: The capability to use 153 * 154 * Test to see if the opener of the socket had when the socket was 155 * created and the current process has the capability @cap in the user 156 * namespace @user_ns. 157 */ 158 bool sk_ns_capable(const struct sock *sk, 159 struct user_namespace *user_ns, int cap) 160 { 161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 162 ns_capable(user_ns, cap); 163 } 164 EXPORT_SYMBOL(sk_ns_capable); 165 166 /** 167 * sk_capable - Socket global capability test 168 * @sk: Socket to use a capability on or through 169 * @cap: The global capability to use 170 * 171 * Test to see if the opener of the socket had when the socket was 172 * created and the current process has the capability @cap in all user 173 * namespaces. 174 */ 175 bool sk_capable(const struct sock *sk, int cap) 176 { 177 return sk_ns_capable(sk, &init_user_ns, cap); 178 } 179 EXPORT_SYMBOL(sk_capable); 180 181 /** 182 * sk_net_capable - Network namespace socket capability test 183 * @sk: Socket to use a capability on or through 184 * @cap: The capability to use 185 * 186 * Test to see if the opener of the socket had when the socket was created 187 * and the current process has the capability @cap over the network namespace 188 * the socket is a member of. 189 */ 190 bool sk_net_capable(const struct sock *sk, int cap) 191 { 192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 193 } 194 EXPORT_SYMBOL(sk_net_capable); 195 196 197 #ifdef CONFIG_MEMCG_KMEM 198 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 199 { 200 struct proto *proto; 201 int ret = 0; 202 203 mutex_lock(&proto_list_mutex); 204 list_for_each_entry(proto, &proto_list, node) { 205 if (proto->init_cgroup) { 206 ret = proto->init_cgroup(memcg, ss); 207 if (ret) 208 goto out; 209 } 210 } 211 212 mutex_unlock(&proto_list_mutex); 213 return ret; 214 out: 215 list_for_each_entry_continue_reverse(proto, &proto_list, node) 216 if (proto->destroy_cgroup) 217 proto->destroy_cgroup(memcg); 218 mutex_unlock(&proto_list_mutex); 219 return ret; 220 } 221 222 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 223 { 224 struct proto *proto; 225 226 mutex_lock(&proto_list_mutex); 227 list_for_each_entry_reverse(proto, &proto_list, node) 228 if (proto->destroy_cgroup) 229 proto->destroy_cgroup(memcg); 230 mutex_unlock(&proto_list_mutex); 231 } 232 #endif 233 234 /* 235 * Each address family might have different locking rules, so we have 236 * one slock key per address family: 237 */ 238 static struct lock_class_key af_family_keys[AF_MAX]; 239 static struct lock_class_key af_family_slock_keys[AF_MAX]; 240 241 #if defined(CONFIG_MEMCG_KMEM) 242 struct static_key memcg_socket_limit_enabled; 243 EXPORT_SYMBOL(memcg_socket_limit_enabled); 244 #endif 245 246 /* 247 * Make lock validator output more readable. (we pre-construct these 248 * strings build-time, so that runtime initialization of socket 249 * locks is fast): 250 */ 251 static const char *const af_family_key_strings[AF_MAX+1] = { 252 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 253 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 254 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 255 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 256 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 257 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 258 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 259 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 260 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 261 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 262 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 263 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 264 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 265 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX" 266 }; 267 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 268 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 269 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 270 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 271 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 272 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 273 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 274 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 275 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 276 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 277 "slock-27" , "slock-28" , "slock-AF_CAN" , 278 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 279 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 280 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 281 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX" 282 }; 283 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 284 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 285 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 286 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 287 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 288 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 289 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 290 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 291 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 292 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 293 "clock-27" , "clock-28" , "clock-AF_CAN" , 294 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 295 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 296 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 297 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX" 298 }; 299 300 /* 301 * sk_callback_lock locking rules are per-address-family, 302 * so split the lock classes by using a per-AF key: 303 */ 304 static struct lock_class_key af_callback_keys[AF_MAX]; 305 306 /* Take into consideration the size of the struct sk_buff overhead in the 307 * determination of these values, since that is non-constant across 308 * platforms. This makes socket queueing behavior and performance 309 * not depend upon such differences. 310 */ 311 #define _SK_MEM_PACKETS 256 312 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 313 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 314 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 315 316 /* Run time adjustable parameters. */ 317 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 318 EXPORT_SYMBOL(sysctl_wmem_max); 319 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 320 EXPORT_SYMBOL(sysctl_rmem_max); 321 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 322 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 323 324 /* Maximal space eaten by iovec or ancillary data plus some space */ 325 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 326 EXPORT_SYMBOL(sysctl_optmem_max); 327 328 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 329 EXPORT_SYMBOL_GPL(memalloc_socks); 330 331 /** 332 * sk_set_memalloc - sets %SOCK_MEMALLOC 333 * @sk: socket to set it on 334 * 335 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 336 * It's the responsibility of the admin to adjust min_free_kbytes 337 * to meet the requirements 338 */ 339 void sk_set_memalloc(struct sock *sk) 340 { 341 sock_set_flag(sk, SOCK_MEMALLOC); 342 sk->sk_allocation |= __GFP_MEMALLOC; 343 static_key_slow_inc(&memalloc_socks); 344 } 345 EXPORT_SYMBOL_GPL(sk_set_memalloc); 346 347 void sk_clear_memalloc(struct sock *sk) 348 { 349 sock_reset_flag(sk, SOCK_MEMALLOC); 350 sk->sk_allocation &= ~__GFP_MEMALLOC; 351 static_key_slow_dec(&memalloc_socks); 352 353 /* 354 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 355 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 356 * it has rmem allocations there is a risk that the user of the 357 * socket cannot make forward progress due to exceeding the rmem 358 * limits. By rights, sk_clear_memalloc() should only be called 359 * on sockets being torn down but warn and reset the accounting if 360 * that assumption breaks. 361 */ 362 if (WARN_ON(sk->sk_forward_alloc)) 363 sk_mem_reclaim(sk); 364 } 365 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 366 367 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 368 { 369 int ret; 370 unsigned long pflags = current->flags; 371 372 /* these should have been dropped before queueing */ 373 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 374 375 current->flags |= PF_MEMALLOC; 376 ret = sk->sk_backlog_rcv(sk, skb); 377 tsk_restore_flags(current, pflags, PF_MEMALLOC); 378 379 return ret; 380 } 381 EXPORT_SYMBOL(__sk_backlog_rcv); 382 383 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 384 { 385 struct timeval tv; 386 387 if (optlen < sizeof(tv)) 388 return -EINVAL; 389 if (copy_from_user(&tv, optval, sizeof(tv))) 390 return -EFAULT; 391 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 392 return -EDOM; 393 394 if (tv.tv_sec < 0) { 395 static int warned __read_mostly; 396 397 *timeo_p = 0; 398 if (warned < 10 && net_ratelimit()) { 399 warned++; 400 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 401 __func__, current->comm, task_pid_nr(current)); 402 } 403 return 0; 404 } 405 *timeo_p = MAX_SCHEDULE_TIMEOUT; 406 if (tv.tv_sec == 0 && tv.tv_usec == 0) 407 return 0; 408 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 409 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 410 return 0; 411 } 412 413 static void sock_warn_obsolete_bsdism(const char *name) 414 { 415 static int warned; 416 static char warncomm[TASK_COMM_LEN]; 417 if (strcmp(warncomm, current->comm) && warned < 5) { 418 strcpy(warncomm, current->comm); 419 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 420 warncomm, name); 421 warned++; 422 } 423 } 424 425 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 426 427 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 428 { 429 if (sk->sk_flags & flags) { 430 sk->sk_flags &= ~flags; 431 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 432 net_disable_timestamp(); 433 } 434 } 435 436 437 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 438 { 439 int err; 440 unsigned long flags; 441 struct sk_buff_head *list = &sk->sk_receive_queue; 442 443 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 444 atomic_inc(&sk->sk_drops); 445 trace_sock_rcvqueue_full(sk, skb); 446 return -ENOMEM; 447 } 448 449 err = sk_filter(sk, skb); 450 if (err) 451 return err; 452 453 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 454 atomic_inc(&sk->sk_drops); 455 return -ENOBUFS; 456 } 457 458 skb->dev = NULL; 459 skb_set_owner_r(skb, sk); 460 461 /* we escape from rcu protected region, make sure we dont leak 462 * a norefcounted dst 463 */ 464 skb_dst_force(skb); 465 466 spin_lock_irqsave(&list->lock, flags); 467 skb->dropcount = atomic_read(&sk->sk_drops); 468 __skb_queue_tail(list, skb); 469 spin_unlock_irqrestore(&list->lock, flags); 470 471 if (!sock_flag(sk, SOCK_DEAD)) 472 sk->sk_data_ready(sk); 473 return 0; 474 } 475 EXPORT_SYMBOL(sock_queue_rcv_skb); 476 477 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 478 { 479 int rc = NET_RX_SUCCESS; 480 481 if (sk_filter(sk, skb)) 482 goto discard_and_relse; 483 484 skb->dev = NULL; 485 486 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 487 atomic_inc(&sk->sk_drops); 488 goto discard_and_relse; 489 } 490 if (nested) 491 bh_lock_sock_nested(sk); 492 else 493 bh_lock_sock(sk); 494 if (!sock_owned_by_user(sk)) { 495 /* 496 * trylock + unlock semantics: 497 */ 498 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 499 500 rc = sk_backlog_rcv(sk, skb); 501 502 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 503 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 504 bh_unlock_sock(sk); 505 atomic_inc(&sk->sk_drops); 506 goto discard_and_relse; 507 } 508 509 bh_unlock_sock(sk); 510 out: 511 sock_put(sk); 512 return rc; 513 discard_and_relse: 514 kfree_skb(skb); 515 goto out; 516 } 517 EXPORT_SYMBOL(sk_receive_skb); 518 519 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 520 { 521 struct dst_entry *dst = __sk_dst_get(sk); 522 523 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 524 sk_tx_queue_clear(sk); 525 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 526 dst_release(dst); 527 return NULL; 528 } 529 530 return dst; 531 } 532 EXPORT_SYMBOL(__sk_dst_check); 533 534 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 535 { 536 struct dst_entry *dst = sk_dst_get(sk); 537 538 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 539 sk_dst_reset(sk); 540 dst_release(dst); 541 return NULL; 542 } 543 544 return dst; 545 } 546 EXPORT_SYMBOL(sk_dst_check); 547 548 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 549 int optlen) 550 { 551 int ret = -ENOPROTOOPT; 552 #ifdef CONFIG_NETDEVICES 553 struct net *net = sock_net(sk); 554 char devname[IFNAMSIZ]; 555 int index; 556 557 /* Sorry... */ 558 ret = -EPERM; 559 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 560 goto out; 561 562 ret = -EINVAL; 563 if (optlen < 0) 564 goto out; 565 566 /* Bind this socket to a particular device like "eth0", 567 * as specified in the passed interface name. If the 568 * name is "" or the option length is zero the socket 569 * is not bound. 570 */ 571 if (optlen > IFNAMSIZ - 1) 572 optlen = IFNAMSIZ - 1; 573 memset(devname, 0, sizeof(devname)); 574 575 ret = -EFAULT; 576 if (copy_from_user(devname, optval, optlen)) 577 goto out; 578 579 index = 0; 580 if (devname[0] != '\0') { 581 struct net_device *dev; 582 583 rcu_read_lock(); 584 dev = dev_get_by_name_rcu(net, devname); 585 if (dev) 586 index = dev->ifindex; 587 rcu_read_unlock(); 588 ret = -ENODEV; 589 if (!dev) 590 goto out; 591 } 592 593 lock_sock(sk); 594 sk->sk_bound_dev_if = index; 595 sk_dst_reset(sk); 596 release_sock(sk); 597 598 ret = 0; 599 600 out: 601 #endif 602 603 return ret; 604 } 605 606 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 607 int __user *optlen, int len) 608 { 609 int ret = -ENOPROTOOPT; 610 #ifdef CONFIG_NETDEVICES 611 struct net *net = sock_net(sk); 612 char devname[IFNAMSIZ]; 613 614 if (sk->sk_bound_dev_if == 0) { 615 len = 0; 616 goto zero; 617 } 618 619 ret = -EINVAL; 620 if (len < IFNAMSIZ) 621 goto out; 622 623 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 624 if (ret) 625 goto out; 626 627 len = strlen(devname) + 1; 628 629 ret = -EFAULT; 630 if (copy_to_user(optval, devname, len)) 631 goto out; 632 633 zero: 634 ret = -EFAULT; 635 if (put_user(len, optlen)) 636 goto out; 637 638 ret = 0; 639 640 out: 641 #endif 642 643 return ret; 644 } 645 646 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 647 { 648 if (valbool) 649 sock_set_flag(sk, bit); 650 else 651 sock_reset_flag(sk, bit); 652 } 653 654 /* 655 * This is meant for all protocols to use and covers goings on 656 * at the socket level. Everything here is generic. 657 */ 658 659 int sock_setsockopt(struct socket *sock, int level, int optname, 660 char __user *optval, unsigned int optlen) 661 { 662 struct sock *sk = sock->sk; 663 int val; 664 int valbool; 665 struct linger ling; 666 int ret = 0; 667 668 /* 669 * Options without arguments 670 */ 671 672 if (optname == SO_BINDTODEVICE) 673 return sock_setbindtodevice(sk, optval, optlen); 674 675 if (optlen < sizeof(int)) 676 return -EINVAL; 677 678 if (get_user(val, (int __user *)optval)) 679 return -EFAULT; 680 681 valbool = val ? 1 : 0; 682 683 lock_sock(sk); 684 685 switch (optname) { 686 case SO_DEBUG: 687 if (val && !capable(CAP_NET_ADMIN)) 688 ret = -EACCES; 689 else 690 sock_valbool_flag(sk, SOCK_DBG, valbool); 691 break; 692 case SO_REUSEADDR: 693 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 694 break; 695 case SO_REUSEPORT: 696 sk->sk_reuseport = valbool; 697 break; 698 case SO_TYPE: 699 case SO_PROTOCOL: 700 case SO_DOMAIN: 701 case SO_ERROR: 702 ret = -ENOPROTOOPT; 703 break; 704 case SO_DONTROUTE: 705 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 706 break; 707 case SO_BROADCAST: 708 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 709 break; 710 case SO_SNDBUF: 711 /* Don't error on this BSD doesn't and if you think 712 * about it this is right. Otherwise apps have to 713 * play 'guess the biggest size' games. RCVBUF/SNDBUF 714 * are treated in BSD as hints 715 */ 716 val = min_t(u32, val, sysctl_wmem_max); 717 set_sndbuf: 718 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 719 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 720 /* Wake up sending tasks if we upped the value. */ 721 sk->sk_write_space(sk); 722 break; 723 724 case SO_SNDBUFFORCE: 725 if (!capable(CAP_NET_ADMIN)) { 726 ret = -EPERM; 727 break; 728 } 729 goto set_sndbuf; 730 731 case SO_RCVBUF: 732 /* Don't error on this BSD doesn't and if you think 733 * about it this is right. Otherwise apps have to 734 * play 'guess the biggest size' games. RCVBUF/SNDBUF 735 * are treated in BSD as hints 736 */ 737 val = min_t(u32, val, sysctl_rmem_max); 738 set_rcvbuf: 739 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 740 /* 741 * We double it on the way in to account for 742 * "struct sk_buff" etc. overhead. Applications 743 * assume that the SO_RCVBUF setting they make will 744 * allow that much actual data to be received on that 745 * socket. 746 * 747 * Applications are unaware that "struct sk_buff" and 748 * other overheads allocate from the receive buffer 749 * during socket buffer allocation. 750 * 751 * And after considering the possible alternatives, 752 * returning the value we actually used in getsockopt 753 * is the most desirable behavior. 754 */ 755 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 756 break; 757 758 case SO_RCVBUFFORCE: 759 if (!capable(CAP_NET_ADMIN)) { 760 ret = -EPERM; 761 break; 762 } 763 goto set_rcvbuf; 764 765 case SO_KEEPALIVE: 766 #ifdef CONFIG_INET 767 if (sk->sk_protocol == IPPROTO_TCP && 768 sk->sk_type == SOCK_STREAM) 769 tcp_set_keepalive(sk, valbool); 770 #endif 771 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 772 break; 773 774 case SO_OOBINLINE: 775 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 776 break; 777 778 case SO_NO_CHECK: 779 sk->sk_no_check_tx = valbool; 780 break; 781 782 case SO_PRIORITY: 783 if ((val >= 0 && val <= 6) || 784 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 785 sk->sk_priority = val; 786 else 787 ret = -EPERM; 788 break; 789 790 case SO_LINGER: 791 if (optlen < sizeof(ling)) { 792 ret = -EINVAL; /* 1003.1g */ 793 break; 794 } 795 if (copy_from_user(&ling, optval, sizeof(ling))) { 796 ret = -EFAULT; 797 break; 798 } 799 if (!ling.l_onoff) 800 sock_reset_flag(sk, SOCK_LINGER); 801 else { 802 #if (BITS_PER_LONG == 32) 803 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 804 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 805 else 806 #endif 807 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 808 sock_set_flag(sk, SOCK_LINGER); 809 } 810 break; 811 812 case SO_BSDCOMPAT: 813 sock_warn_obsolete_bsdism("setsockopt"); 814 break; 815 816 case SO_PASSCRED: 817 if (valbool) 818 set_bit(SOCK_PASSCRED, &sock->flags); 819 else 820 clear_bit(SOCK_PASSCRED, &sock->flags); 821 break; 822 823 case SO_TIMESTAMP: 824 case SO_TIMESTAMPNS: 825 if (valbool) { 826 if (optname == SO_TIMESTAMP) 827 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 828 else 829 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 830 sock_set_flag(sk, SOCK_RCVTSTAMP); 831 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 832 } else { 833 sock_reset_flag(sk, SOCK_RCVTSTAMP); 834 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 835 } 836 break; 837 838 case SO_TIMESTAMPING: 839 if (val & ~SOF_TIMESTAMPING_MASK) { 840 ret = -EINVAL; 841 break; 842 } 843 if (val & SOF_TIMESTAMPING_OPT_ID && 844 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 845 if (sk->sk_protocol == IPPROTO_TCP) { 846 if (sk->sk_state != TCP_ESTABLISHED) { 847 ret = -EINVAL; 848 break; 849 } 850 sk->sk_tskey = tcp_sk(sk)->snd_una; 851 } else { 852 sk->sk_tskey = 0; 853 } 854 } 855 sk->sk_tsflags = val; 856 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 857 sock_enable_timestamp(sk, 858 SOCK_TIMESTAMPING_RX_SOFTWARE); 859 else 860 sock_disable_timestamp(sk, 861 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 862 break; 863 864 case SO_RCVLOWAT: 865 if (val < 0) 866 val = INT_MAX; 867 sk->sk_rcvlowat = val ? : 1; 868 break; 869 870 case SO_RCVTIMEO: 871 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 872 break; 873 874 case SO_SNDTIMEO: 875 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 876 break; 877 878 case SO_ATTACH_FILTER: 879 ret = -EINVAL; 880 if (optlen == sizeof(struct sock_fprog)) { 881 struct sock_fprog fprog; 882 883 ret = -EFAULT; 884 if (copy_from_user(&fprog, optval, sizeof(fprog))) 885 break; 886 887 ret = sk_attach_filter(&fprog, sk); 888 } 889 break; 890 891 case SO_ATTACH_BPF: 892 ret = -EINVAL; 893 if (optlen == sizeof(u32)) { 894 u32 ufd; 895 896 ret = -EFAULT; 897 if (copy_from_user(&ufd, optval, sizeof(ufd))) 898 break; 899 900 ret = sk_attach_bpf(ufd, sk); 901 } 902 break; 903 904 case SO_DETACH_FILTER: 905 ret = sk_detach_filter(sk); 906 break; 907 908 case SO_LOCK_FILTER: 909 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 910 ret = -EPERM; 911 else 912 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 913 break; 914 915 case SO_PASSSEC: 916 if (valbool) 917 set_bit(SOCK_PASSSEC, &sock->flags); 918 else 919 clear_bit(SOCK_PASSSEC, &sock->flags); 920 break; 921 case SO_MARK: 922 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 923 ret = -EPERM; 924 else 925 sk->sk_mark = val; 926 break; 927 928 /* We implement the SO_SNDLOWAT etc to 929 not be settable (1003.1g 5.3) */ 930 case SO_RXQ_OVFL: 931 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 932 break; 933 934 case SO_WIFI_STATUS: 935 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 936 break; 937 938 case SO_PEEK_OFF: 939 if (sock->ops->set_peek_off) 940 ret = sock->ops->set_peek_off(sk, val); 941 else 942 ret = -EOPNOTSUPP; 943 break; 944 945 case SO_NOFCS: 946 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 947 break; 948 949 case SO_SELECT_ERR_QUEUE: 950 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 951 break; 952 953 #ifdef CONFIG_NET_RX_BUSY_POLL 954 case SO_BUSY_POLL: 955 /* allow unprivileged users to decrease the value */ 956 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 957 ret = -EPERM; 958 else { 959 if (val < 0) 960 ret = -EINVAL; 961 else 962 sk->sk_ll_usec = val; 963 } 964 break; 965 #endif 966 967 case SO_MAX_PACING_RATE: 968 sk->sk_max_pacing_rate = val; 969 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 970 sk->sk_max_pacing_rate); 971 break; 972 973 default: 974 ret = -ENOPROTOOPT; 975 break; 976 } 977 release_sock(sk); 978 return ret; 979 } 980 EXPORT_SYMBOL(sock_setsockopt); 981 982 983 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 984 struct ucred *ucred) 985 { 986 ucred->pid = pid_vnr(pid); 987 ucred->uid = ucred->gid = -1; 988 if (cred) { 989 struct user_namespace *current_ns = current_user_ns(); 990 991 ucred->uid = from_kuid_munged(current_ns, cred->euid); 992 ucred->gid = from_kgid_munged(current_ns, cred->egid); 993 } 994 } 995 996 int sock_getsockopt(struct socket *sock, int level, int optname, 997 char __user *optval, int __user *optlen) 998 { 999 struct sock *sk = sock->sk; 1000 1001 union { 1002 int val; 1003 struct linger ling; 1004 struct timeval tm; 1005 } v; 1006 1007 int lv = sizeof(int); 1008 int len; 1009 1010 if (get_user(len, optlen)) 1011 return -EFAULT; 1012 if (len < 0) 1013 return -EINVAL; 1014 1015 memset(&v, 0, sizeof(v)); 1016 1017 switch (optname) { 1018 case SO_DEBUG: 1019 v.val = sock_flag(sk, SOCK_DBG); 1020 break; 1021 1022 case SO_DONTROUTE: 1023 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1024 break; 1025 1026 case SO_BROADCAST: 1027 v.val = sock_flag(sk, SOCK_BROADCAST); 1028 break; 1029 1030 case SO_SNDBUF: 1031 v.val = sk->sk_sndbuf; 1032 break; 1033 1034 case SO_RCVBUF: 1035 v.val = sk->sk_rcvbuf; 1036 break; 1037 1038 case SO_REUSEADDR: 1039 v.val = sk->sk_reuse; 1040 break; 1041 1042 case SO_REUSEPORT: 1043 v.val = sk->sk_reuseport; 1044 break; 1045 1046 case SO_KEEPALIVE: 1047 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1048 break; 1049 1050 case SO_TYPE: 1051 v.val = sk->sk_type; 1052 break; 1053 1054 case SO_PROTOCOL: 1055 v.val = sk->sk_protocol; 1056 break; 1057 1058 case SO_DOMAIN: 1059 v.val = sk->sk_family; 1060 break; 1061 1062 case SO_ERROR: 1063 v.val = -sock_error(sk); 1064 if (v.val == 0) 1065 v.val = xchg(&sk->sk_err_soft, 0); 1066 break; 1067 1068 case SO_OOBINLINE: 1069 v.val = sock_flag(sk, SOCK_URGINLINE); 1070 break; 1071 1072 case SO_NO_CHECK: 1073 v.val = sk->sk_no_check_tx; 1074 break; 1075 1076 case SO_PRIORITY: 1077 v.val = sk->sk_priority; 1078 break; 1079 1080 case SO_LINGER: 1081 lv = sizeof(v.ling); 1082 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1083 v.ling.l_linger = sk->sk_lingertime / HZ; 1084 break; 1085 1086 case SO_BSDCOMPAT: 1087 sock_warn_obsolete_bsdism("getsockopt"); 1088 break; 1089 1090 case SO_TIMESTAMP: 1091 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1092 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1093 break; 1094 1095 case SO_TIMESTAMPNS: 1096 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1097 break; 1098 1099 case SO_TIMESTAMPING: 1100 v.val = sk->sk_tsflags; 1101 break; 1102 1103 case SO_RCVTIMEO: 1104 lv = sizeof(struct timeval); 1105 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1106 v.tm.tv_sec = 0; 1107 v.tm.tv_usec = 0; 1108 } else { 1109 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1110 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1111 } 1112 break; 1113 1114 case SO_SNDTIMEO: 1115 lv = sizeof(struct timeval); 1116 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1117 v.tm.tv_sec = 0; 1118 v.tm.tv_usec = 0; 1119 } else { 1120 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1121 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1122 } 1123 break; 1124 1125 case SO_RCVLOWAT: 1126 v.val = sk->sk_rcvlowat; 1127 break; 1128 1129 case SO_SNDLOWAT: 1130 v.val = 1; 1131 break; 1132 1133 case SO_PASSCRED: 1134 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1135 break; 1136 1137 case SO_PEERCRED: 1138 { 1139 struct ucred peercred; 1140 if (len > sizeof(peercred)) 1141 len = sizeof(peercred); 1142 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1143 if (copy_to_user(optval, &peercred, len)) 1144 return -EFAULT; 1145 goto lenout; 1146 } 1147 1148 case SO_PEERNAME: 1149 { 1150 char address[128]; 1151 1152 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1153 return -ENOTCONN; 1154 if (lv < len) 1155 return -EINVAL; 1156 if (copy_to_user(optval, address, len)) 1157 return -EFAULT; 1158 goto lenout; 1159 } 1160 1161 /* Dubious BSD thing... Probably nobody even uses it, but 1162 * the UNIX standard wants it for whatever reason... -DaveM 1163 */ 1164 case SO_ACCEPTCONN: 1165 v.val = sk->sk_state == TCP_LISTEN; 1166 break; 1167 1168 case SO_PASSSEC: 1169 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1170 break; 1171 1172 case SO_PEERSEC: 1173 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1174 1175 case SO_MARK: 1176 v.val = sk->sk_mark; 1177 break; 1178 1179 case SO_RXQ_OVFL: 1180 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1181 break; 1182 1183 case SO_WIFI_STATUS: 1184 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1185 break; 1186 1187 case SO_PEEK_OFF: 1188 if (!sock->ops->set_peek_off) 1189 return -EOPNOTSUPP; 1190 1191 v.val = sk->sk_peek_off; 1192 break; 1193 case SO_NOFCS: 1194 v.val = sock_flag(sk, SOCK_NOFCS); 1195 break; 1196 1197 case SO_BINDTODEVICE: 1198 return sock_getbindtodevice(sk, optval, optlen, len); 1199 1200 case SO_GET_FILTER: 1201 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1202 if (len < 0) 1203 return len; 1204 1205 goto lenout; 1206 1207 case SO_LOCK_FILTER: 1208 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1209 break; 1210 1211 case SO_BPF_EXTENSIONS: 1212 v.val = bpf_tell_extensions(); 1213 break; 1214 1215 case SO_SELECT_ERR_QUEUE: 1216 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1217 break; 1218 1219 #ifdef CONFIG_NET_RX_BUSY_POLL 1220 case SO_BUSY_POLL: 1221 v.val = sk->sk_ll_usec; 1222 break; 1223 #endif 1224 1225 case SO_MAX_PACING_RATE: 1226 v.val = sk->sk_max_pacing_rate; 1227 break; 1228 1229 case SO_INCOMING_CPU: 1230 v.val = sk->sk_incoming_cpu; 1231 break; 1232 1233 default: 1234 return -ENOPROTOOPT; 1235 } 1236 1237 if (len > lv) 1238 len = lv; 1239 if (copy_to_user(optval, &v, len)) 1240 return -EFAULT; 1241 lenout: 1242 if (put_user(len, optlen)) 1243 return -EFAULT; 1244 return 0; 1245 } 1246 1247 /* 1248 * Initialize an sk_lock. 1249 * 1250 * (We also register the sk_lock with the lock validator.) 1251 */ 1252 static inline void sock_lock_init(struct sock *sk) 1253 { 1254 sock_lock_init_class_and_name(sk, 1255 af_family_slock_key_strings[sk->sk_family], 1256 af_family_slock_keys + sk->sk_family, 1257 af_family_key_strings[sk->sk_family], 1258 af_family_keys + sk->sk_family); 1259 } 1260 1261 /* 1262 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1263 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1264 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1265 */ 1266 static void sock_copy(struct sock *nsk, const struct sock *osk) 1267 { 1268 #ifdef CONFIG_SECURITY_NETWORK 1269 void *sptr = nsk->sk_security; 1270 #endif 1271 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1272 1273 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1274 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1275 1276 #ifdef CONFIG_SECURITY_NETWORK 1277 nsk->sk_security = sptr; 1278 security_sk_clone(osk, nsk); 1279 #endif 1280 } 1281 1282 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1283 { 1284 unsigned long nulls1, nulls2; 1285 1286 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1287 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1288 if (nulls1 > nulls2) 1289 swap(nulls1, nulls2); 1290 1291 if (nulls1 != 0) 1292 memset((char *)sk, 0, nulls1); 1293 memset((char *)sk + nulls1 + sizeof(void *), 0, 1294 nulls2 - nulls1 - sizeof(void *)); 1295 memset((char *)sk + nulls2 + sizeof(void *), 0, 1296 size - nulls2 - sizeof(void *)); 1297 } 1298 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1299 1300 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1301 int family) 1302 { 1303 struct sock *sk; 1304 struct kmem_cache *slab; 1305 1306 slab = prot->slab; 1307 if (slab != NULL) { 1308 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1309 if (!sk) 1310 return sk; 1311 if (priority & __GFP_ZERO) { 1312 if (prot->clear_sk) 1313 prot->clear_sk(sk, prot->obj_size); 1314 else 1315 sk_prot_clear_nulls(sk, prot->obj_size); 1316 } 1317 } else 1318 sk = kmalloc(prot->obj_size, priority); 1319 1320 if (sk != NULL) { 1321 kmemcheck_annotate_bitfield(sk, flags); 1322 1323 if (security_sk_alloc(sk, family, priority)) 1324 goto out_free; 1325 1326 if (!try_module_get(prot->owner)) 1327 goto out_free_sec; 1328 sk_tx_queue_clear(sk); 1329 } 1330 1331 return sk; 1332 1333 out_free_sec: 1334 security_sk_free(sk); 1335 out_free: 1336 if (slab != NULL) 1337 kmem_cache_free(slab, sk); 1338 else 1339 kfree(sk); 1340 return NULL; 1341 } 1342 1343 static void sk_prot_free(struct proto *prot, struct sock *sk) 1344 { 1345 struct kmem_cache *slab; 1346 struct module *owner; 1347 1348 owner = prot->owner; 1349 slab = prot->slab; 1350 1351 security_sk_free(sk); 1352 if (slab != NULL) 1353 kmem_cache_free(slab, sk); 1354 else 1355 kfree(sk); 1356 module_put(owner); 1357 } 1358 1359 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 1360 void sock_update_netprioidx(struct sock *sk) 1361 { 1362 if (in_interrupt()) 1363 return; 1364 1365 sk->sk_cgrp_prioidx = task_netprioidx(current); 1366 } 1367 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1368 #endif 1369 1370 /** 1371 * sk_alloc - All socket objects are allocated here 1372 * @net: the applicable net namespace 1373 * @family: protocol family 1374 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1375 * @prot: struct proto associated with this new sock instance 1376 */ 1377 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1378 struct proto *prot) 1379 { 1380 struct sock *sk; 1381 1382 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1383 if (sk) { 1384 sk->sk_family = family; 1385 /* 1386 * See comment in struct sock definition to understand 1387 * why we need sk_prot_creator -acme 1388 */ 1389 sk->sk_prot = sk->sk_prot_creator = prot; 1390 sock_lock_init(sk); 1391 sock_net_set(sk, get_net(net)); 1392 atomic_set(&sk->sk_wmem_alloc, 1); 1393 1394 sock_update_classid(sk); 1395 sock_update_netprioidx(sk); 1396 } 1397 1398 return sk; 1399 } 1400 EXPORT_SYMBOL(sk_alloc); 1401 1402 static void __sk_free(struct sock *sk) 1403 { 1404 struct sk_filter *filter; 1405 1406 if (sk->sk_destruct) 1407 sk->sk_destruct(sk); 1408 1409 filter = rcu_dereference_check(sk->sk_filter, 1410 atomic_read(&sk->sk_wmem_alloc) == 0); 1411 if (filter) { 1412 sk_filter_uncharge(sk, filter); 1413 RCU_INIT_POINTER(sk->sk_filter, NULL); 1414 } 1415 1416 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1417 1418 if (atomic_read(&sk->sk_omem_alloc)) 1419 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1420 __func__, atomic_read(&sk->sk_omem_alloc)); 1421 1422 if (sk->sk_peer_cred) 1423 put_cred(sk->sk_peer_cred); 1424 put_pid(sk->sk_peer_pid); 1425 put_net(sock_net(sk)); 1426 sk_prot_free(sk->sk_prot_creator, sk); 1427 } 1428 1429 void sk_free(struct sock *sk) 1430 { 1431 /* 1432 * We subtract one from sk_wmem_alloc and can know if 1433 * some packets are still in some tx queue. 1434 * If not null, sock_wfree() will call __sk_free(sk) later 1435 */ 1436 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1437 __sk_free(sk); 1438 } 1439 EXPORT_SYMBOL(sk_free); 1440 1441 /* 1442 * Last sock_put should drop reference to sk->sk_net. It has already 1443 * been dropped in sk_change_net. Taking reference to stopping namespace 1444 * is not an option. 1445 * Take reference to a socket to remove it from hash _alive_ and after that 1446 * destroy it in the context of init_net. 1447 */ 1448 void sk_release_kernel(struct sock *sk) 1449 { 1450 if (sk == NULL || sk->sk_socket == NULL) 1451 return; 1452 1453 sock_hold(sk); 1454 sock_release(sk->sk_socket); 1455 release_net(sock_net(sk)); 1456 sock_net_set(sk, get_net(&init_net)); 1457 sock_put(sk); 1458 } 1459 EXPORT_SYMBOL(sk_release_kernel); 1460 1461 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1462 { 1463 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1464 sock_update_memcg(newsk); 1465 } 1466 1467 /** 1468 * sk_clone_lock - clone a socket, and lock its clone 1469 * @sk: the socket to clone 1470 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1471 * 1472 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1473 */ 1474 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1475 { 1476 struct sock *newsk; 1477 bool is_charged = true; 1478 1479 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1480 if (newsk != NULL) { 1481 struct sk_filter *filter; 1482 1483 sock_copy(newsk, sk); 1484 1485 /* SANITY */ 1486 get_net(sock_net(newsk)); 1487 sk_node_init(&newsk->sk_node); 1488 sock_lock_init(newsk); 1489 bh_lock_sock(newsk); 1490 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1491 newsk->sk_backlog.len = 0; 1492 1493 atomic_set(&newsk->sk_rmem_alloc, 0); 1494 /* 1495 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1496 */ 1497 atomic_set(&newsk->sk_wmem_alloc, 1); 1498 atomic_set(&newsk->sk_omem_alloc, 0); 1499 skb_queue_head_init(&newsk->sk_receive_queue); 1500 skb_queue_head_init(&newsk->sk_write_queue); 1501 1502 spin_lock_init(&newsk->sk_dst_lock); 1503 rwlock_init(&newsk->sk_callback_lock); 1504 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1505 af_callback_keys + newsk->sk_family, 1506 af_family_clock_key_strings[newsk->sk_family]); 1507 1508 newsk->sk_dst_cache = NULL; 1509 newsk->sk_wmem_queued = 0; 1510 newsk->sk_forward_alloc = 0; 1511 newsk->sk_send_head = NULL; 1512 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1513 1514 sock_reset_flag(newsk, SOCK_DONE); 1515 skb_queue_head_init(&newsk->sk_error_queue); 1516 1517 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1518 if (filter != NULL) 1519 /* though it's an empty new sock, the charging may fail 1520 * if sysctl_optmem_max was changed between creation of 1521 * original socket and cloning 1522 */ 1523 is_charged = sk_filter_charge(newsk, filter); 1524 1525 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) { 1526 /* It is still raw copy of parent, so invalidate 1527 * destructor and make plain sk_free() */ 1528 newsk->sk_destruct = NULL; 1529 bh_unlock_sock(newsk); 1530 sk_free(newsk); 1531 newsk = NULL; 1532 goto out; 1533 } 1534 1535 newsk->sk_err = 0; 1536 newsk->sk_priority = 0; 1537 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1538 /* 1539 * Before updating sk_refcnt, we must commit prior changes to memory 1540 * (Documentation/RCU/rculist_nulls.txt for details) 1541 */ 1542 smp_wmb(); 1543 atomic_set(&newsk->sk_refcnt, 2); 1544 1545 /* 1546 * Increment the counter in the same struct proto as the master 1547 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1548 * is the same as sk->sk_prot->socks, as this field was copied 1549 * with memcpy). 1550 * 1551 * This _changes_ the previous behaviour, where 1552 * tcp_create_openreq_child always was incrementing the 1553 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1554 * to be taken into account in all callers. -acme 1555 */ 1556 sk_refcnt_debug_inc(newsk); 1557 sk_set_socket(newsk, NULL); 1558 newsk->sk_wq = NULL; 1559 1560 sk_update_clone(sk, newsk); 1561 1562 if (newsk->sk_prot->sockets_allocated) 1563 sk_sockets_allocated_inc(newsk); 1564 1565 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1566 net_enable_timestamp(); 1567 } 1568 out: 1569 return newsk; 1570 } 1571 EXPORT_SYMBOL_GPL(sk_clone_lock); 1572 1573 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1574 { 1575 __sk_dst_set(sk, dst); 1576 sk->sk_route_caps = dst->dev->features; 1577 if (sk->sk_route_caps & NETIF_F_GSO) 1578 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1579 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1580 if (sk_can_gso(sk)) { 1581 if (dst->header_len) { 1582 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1583 } else { 1584 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1585 sk->sk_gso_max_size = dst->dev->gso_max_size; 1586 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1587 } 1588 } 1589 } 1590 EXPORT_SYMBOL_GPL(sk_setup_caps); 1591 1592 /* 1593 * Simple resource managers for sockets. 1594 */ 1595 1596 1597 /* 1598 * Write buffer destructor automatically called from kfree_skb. 1599 */ 1600 void sock_wfree(struct sk_buff *skb) 1601 { 1602 struct sock *sk = skb->sk; 1603 unsigned int len = skb->truesize; 1604 1605 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1606 /* 1607 * Keep a reference on sk_wmem_alloc, this will be released 1608 * after sk_write_space() call 1609 */ 1610 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1611 sk->sk_write_space(sk); 1612 len = 1; 1613 } 1614 /* 1615 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1616 * could not do because of in-flight packets 1617 */ 1618 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1619 __sk_free(sk); 1620 } 1621 EXPORT_SYMBOL(sock_wfree); 1622 1623 void skb_orphan_partial(struct sk_buff *skb) 1624 { 1625 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1626 * so we do not completely orphan skb, but transfert all 1627 * accounted bytes but one, to avoid unexpected reorders. 1628 */ 1629 if (skb->destructor == sock_wfree 1630 #ifdef CONFIG_INET 1631 || skb->destructor == tcp_wfree 1632 #endif 1633 ) { 1634 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1635 skb->truesize = 1; 1636 } else { 1637 skb_orphan(skb); 1638 } 1639 } 1640 EXPORT_SYMBOL(skb_orphan_partial); 1641 1642 /* 1643 * Read buffer destructor automatically called from kfree_skb. 1644 */ 1645 void sock_rfree(struct sk_buff *skb) 1646 { 1647 struct sock *sk = skb->sk; 1648 unsigned int len = skb->truesize; 1649 1650 atomic_sub(len, &sk->sk_rmem_alloc); 1651 sk_mem_uncharge(sk, len); 1652 } 1653 EXPORT_SYMBOL(sock_rfree); 1654 1655 void sock_efree(struct sk_buff *skb) 1656 { 1657 sock_put(skb->sk); 1658 } 1659 EXPORT_SYMBOL(sock_efree); 1660 1661 #ifdef CONFIG_INET 1662 void sock_edemux(struct sk_buff *skb) 1663 { 1664 struct sock *sk = skb->sk; 1665 1666 if (sk->sk_state == TCP_TIME_WAIT) 1667 inet_twsk_put(inet_twsk(sk)); 1668 else 1669 sock_put(sk); 1670 } 1671 EXPORT_SYMBOL(sock_edemux); 1672 #endif 1673 1674 kuid_t sock_i_uid(struct sock *sk) 1675 { 1676 kuid_t uid; 1677 1678 read_lock_bh(&sk->sk_callback_lock); 1679 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1680 read_unlock_bh(&sk->sk_callback_lock); 1681 return uid; 1682 } 1683 EXPORT_SYMBOL(sock_i_uid); 1684 1685 unsigned long sock_i_ino(struct sock *sk) 1686 { 1687 unsigned long ino; 1688 1689 read_lock_bh(&sk->sk_callback_lock); 1690 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1691 read_unlock_bh(&sk->sk_callback_lock); 1692 return ino; 1693 } 1694 EXPORT_SYMBOL(sock_i_ino); 1695 1696 /* 1697 * Allocate a skb from the socket's send buffer. 1698 */ 1699 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1700 gfp_t priority) 1701 { 1702 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1703 struct sk_buff *skb = alloc_skb(size, priority); 1704 if (skb) { 1705 skb_set_owner_w(skb, sk); 1706 return skb; 1707 } 1708 } 1709 return NULL; 1710 } 1711 EXPORT_SYMBOL(sock_wmalloc); 1712 1713 /* 1714 * Allocate a memory block from the socket's option memory buffer. 1715 */ 1716 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1717 { 1718 if ((unsigned int)size <= sysctl_optmem_max && 1719 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1720 void *mem; 1721 /* First do the add, to avoid the race if kmalloc 1722 * might sleep. 1723 */ 1724 atomic_add(size, &sk->sk_omem_alloc); 1725 mem = kmalloc(size, priority); 1726 if (mem) 1727 return mem; 1728 atomic_sub(size, &sk->sk_omem_alloc); 1729 } 1730 return NULL; 1731 } 1732 EXPORT_SYMBOL(sock_kmalloc); 1733 1734 /* Free an option memory block. Note, we actually want the inline 1735 * here as this allows gcc to detect the nullify and fold away the 1736 * condition entirely. 1737 */ 1738 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 1739 const bool nullify) 1740 { 1741 if (WARN_ON_ONCE(!mem)) 1742 return; 1743 if (nullify) 1744 kzfree(mem); 1745 else 1746 kfree(mem); 1747 atomic_sub(size, &sk->sk_omem_alloc); 1748 } 1749 1750 void sock_kfree_s(struct sock *sk, void *mem, int size) 1751 { 1752 __sock_kfree_s(sk, mem, size, false); 1753 } 1754 EXPORT_SYMBOL(sock_kfree_s); 1755 1756 void sock_kzfree_s(struct sock *sk, void *mem, int size) 1757 { 1758 __sock_kfree_s(sk, mem, size, true); 1759 } 1760 EXPORT_SYMBOL(sock_kzfree_s); 1761 1762 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1763 I think, these locks should be removed for datagram sockets. 1764 */ 1765 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1766 { 1767 DEFINE_WAIT(wait); 1768 1769 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1770 for (;;) { 1771 if (!timeo) 1772 break; 1773 if (signal_pending(current)) 1774 break; 1775 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1776 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1777 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1778 break; 1779 if (sk->sk_shutdown & SEND_SHUTDOWN) 1780 break; 1781 if (sk->sk_err) 1782 break; 1783 timeo = schedule_timeout(timeo); 1784 } 1785 finish_wait(sk_sleep(sk), &wait); 1786 return timeo; 1787 } 1788 1789 1790 /* 1791 * Generic send/receive buffer handlers 1792 */ 1793 1794 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1795 unsigned long data_len, int noblock, 1796 int *errcode, int max_page_order) 1797 { 1798 struct sk_buff *skb; 1799 long timeo; 1800 int err; 1801 1802 timeo = sock_sndtimeo(sk, noblock); 1803 for (;;) { 1804 err = sock_error(sk); 1805 if (err != 0) 1806 goto failure; 1807 1808 err = -EPIPE; 1809 if (sk->sk_shutdown & SEND_SHUTDOWN) 1810 goto failure; 1811 1812 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 1813 break; 1814 1815 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1816 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1817 err = -EAGAIN; 1818 if (!timeo) 1819 goto failure; 1820 if (signal_pending(current)) 1821 goto interrupted; 1822 timeo = sock_wait_for_wmem(sk, timeo); 1823 } 1824 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 1825 errcode, sk->sk_allocation); 1826 if (skb) 1827 skb_set_owner_w(skb, sk); 1828 return skb; 1829 1830 interrupted: 1831 err = sock_intr_errno(timeo); 1832 failure: 1833 *errcode = err; 1834 return NULL; 1835 } 1836 EXPORT_SYMBOL(sock_alloc_send_pskb); 1837 1838 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1839 int noblock, int *errcode) 1840 { 1841 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1842 } 1843 EXPORT_SYMBOL(sock_alloc_send_skb); 1844 1845 /* On 32bit arches, an skb frag is limited to 2^15 */ 1846 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1847 1848 /** 1849 * skb_page_frag_refill - check that a page_frag contains enough room 1850 * @sz: minimum size of the fragment we want to get 1851 * @pfrag: pointer to page_frag 1852 * @gfp: priority for memory allocation 1853 * 1854 * Note: While this allocator tries to use high order pages, there is 1855 * no guarantee that allocations succeed. Therefore, @sz MUST be 1856 * less or equal than PAGE_SIZE. 1857 */ 1858 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 1859 { 1860 if (pfrag->page) { 1861 if (atomic_read(&pfrag->page->_count) == 1) { 1862 pfrag->offset = 0; 1863 return true; 1864 } 1865 if (pfrag->offset + sz <= pfrag->size) 1866 return true; 1867 put_page(pfrag->page); 1868 } 1869 1870 pfrag->offset = 0; 1871 if (SKB_FRAG_PAGE_ORDER) { 1872 pfrag->page = alloc_pages(gfp | __GFP_COMP | 1873 __GFP_NOWARN | __GFP_NORETRY, 1874 SKB_FRAG_PAGE_ORDER); 1875 if (likely(pfrag->page)) { 1876 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 1877 return true; 1878 } 1879 } 1880 pfrag->page = alloc_page(gfp); 1881 if (likely(pfrag->page)) { 1882 pfrag->size = PAGE_SIZE; 1883 return true; 1884 } 1885 return false; 1886 } 1887 EXPORT_SYMBOL(skb_page_frag_refill); 1888 1889 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1890 { 1891 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1892 return true; 1893 1894 sk_enter_memory_pressure(sk); 1895 sk_stream_moderate_sndbuf(sk); 1896 return false; 1897 } 1898 EXPORT_SYMBOL(sk_page_frag_refill); 1899 1900 static void __lock_sock(struct sock *sk) 1901 __releases(&sk->sk_lock.slock) 1902 __acquires(&sk->sk_lock.slock) 1903 { 1904 DEFINE_WAIT(wait); 1905 1906 for (;;) { 1907 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1908 TASK_UNINTERRUPTIBLE); 1909 spin_unlock_bh(&sk->sk_lock.slock); 1910 schedule(); 1911 spin_lock_bh(&sk->sk_lock.slock); 1912 if (!sock_owned_by_user(sk)) 1913 break; 1914 } 1915 finish_wait(&sk->sk_lock.wq, &wait); 1916 } 1917 1918 static void __release_sock(struct sock *sk) 1919 __releases(&sk->sk_lock.slock) 1920 __acquires(&sk->sk_lock.slock) 1921 { 1922 struct sk_buff *skb = sk->sk_backlog.head; 1923 1924 do { 1925 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1926 bh_unlock_sock(sk); 1927 1928 do { 1929 struct sk_buff *next = skb->next; 1930 1931 prefetch(next); 1932 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1933 skb->next = NULL; 1934 sk_backlog_rcv(sk, skb); 1935 1936 /* 1937 * We are in process context here with softirqs 1938 * disabled, use cond_resched_softirq() to preempt. 1939 * This is safe to do because we've taken the backlog 1940 * queue private: 1941 */ 1942 cond_resched_softirq(); 1943 1944 skb = next; 1945 } while (skb != NULL); 1946 1947 bh_lock_sock(sk); 1948 } while ((skb = sk->sk_backlog.head) != NULL); 1949 1950 /* 1951 * Doing the zeroing here guarantee we can not loop forever 1952 * while a wild producer attempts to flood us. 1953 */ 1954 sk->sk_backlog.len = 0; 1955 } 1956 1957 /** 1958 * sk_wait_data - wait for data to arrive at sk_receive_queue 1959 * @sk: sock to wait on 1960 * @timeo: for how long 1961 * 1962 * Now socket state including sk->sk_err is changed only under lock, 1963 * hence we may omit checks after joining wait queue. 1964 * We check receive queue before schedule() only as optimization; 1965 * it is very likely that release_sock() added new data. 1966 */ 1967 int sk_wait_data(struct sock *sk, long *timeo) 1968 { 1969 int rc; 1970 DEFINE_WAIT(wait); 1971 1972 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1973 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1974 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1975 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1976 finish_wait(sk_sleep(sk), &wait); 1977 return rc; 1978 } 1979 EXPORT_SYMBOL(sk_wait_data); 1980 1981 /** 1982 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1983 * @sk: socket 1984 * @size: memory size to allocate 1985 * @kind: allocation type 1986 * 1987 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1988 * rmem allocation. This function assumes that protocols which have 1989 * memory_pressure use sk_wmem_queued as write buffer accounting. 1990 */ 1991 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1992 { 1993 struct proto *prot = sk->sk_prot; 1994 int amt = sk_mem_pages(size); 1995 long allocated; 1996 int parent_status = UNDER_LIMIT; 1997 1998 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1999 2000 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 2001 2002 /* Under limit. */ 2003 if (parent_status == UNDER_LIMIT && 2004 allocated <= sk_prot_mem_limits(sk, 0)) { 2005 sk_leave_memory_pressure(sk); 2006 return 1; 2007 } 2008 2009 /* Under pressure. (we or our parents) */ 2010 if ((parent_status > SOFT_LIMIT) || 2011 allocated > sk_prot_mem_limits(sk, 1)) 2012 sk_enter_memory_pressure(sk); 2013 2014 /* Over hard limit (we or our parents) */ 2015 if ((parent_status == OVER_LIMIT) || 2016 (allocated > sk_prot_mem_limits(sk, 2))) 2017 goto suppress_allocation; 2018 2019 /* guarantee minimum buffer size under pressure */ 2020 if (kind == SK_MEM_RECV) { 2021 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2022 return 1; 2023 2024 } else { /* SK_MEM_SEND */ 2025 if (sk->sk_type == SOCK_STREAM) { 2026 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2027 return 1; 2028 } else if (atomic_read(&sk->sk_wmem_alloc) < 2029 prot->sysctl_wmem[0]) 2030 return 1; 2031 } 2032 2033 if (sk_has_memory_pressure(sk)) { 2034 int alloc; 2035 2036 if (!sk_under_memory_pressure(sk)) 2037 return 1; 2038 alloc = sk_sockets_allocated_read_positive(sk); 2039 if (sk_prot_mem_limits(sk, 2) > alloc * 2040 sk_mem_pages(sk->sk_wmem_queued + 2041 atomic_read(&sk->sk_rmem_alloc) + 2042 sk->sk_forward_alloc)) 2043 return 1; 2044 } 2045 2046 suppress_allocation: 2047 2048 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2049 sk_stream_moderate_sndbuf(sk); 2050 2051 /* Fail only if socket is _under_ its sndbuf. 2052 * In this case we cannot block, so that we have to fail. 2053 */ 2054 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2055 return 1; 2056 } 2057 2058 trace_sock_exceed_buf_limit(sk, prot, allocated); 2059 2060 /* Alas. Undo changes. */ 2061 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2062 2063 sk_memory_allocated_sub(sk, amt); 2064 2065 return 0; 2066 } 2067 EXPORT_SYMBOL(__sk_mem_schedule); 2068 2069 /** 2070 * __sk_reclaim - reclaim memory_allocated 2071 * @sk: socket 2072 */ 2073 void __sk_mem_reclaim(struct sock *sk) 2074 { 2075 sk_memory_allocated_sub(sk, 2076 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2077 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2078 2079 if (sk_under_memory_pressure(sk) && 2080 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2081 sk_leave_memory_pressure(sk); 2082 } 2083 EXPORT_SYMBOL(__sk_mem_reclaim); 2084 2085 2086 /* 2087 * Set of default routines for initialising struct proto_ops when 2088 * the protocol does not support a particular function. In certain 2089 * cases where it makes no sense for a protocol to have a "do nothing" 2090 * function, some default processing is provided. 2091 */ 2092 2093 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2094 { 2095 return -EOPNOTSUPP; 2096 } 2097 EXPORT_SYMBOL(sock_no_bind); 2098 2099 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2100 int len, int flags) 2101 { 2102 return -EOPNOTSUPP; 2103 } 2104 EXPORT_SYMBOL(sock_no_connect); 2105 2106 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2107 { 2108 return -EOPNOTSUPP; 2109 } 2110 EXPORT_SYMBOL(sock_no_socketpair); 2111 2112 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2113 { 2114 return -EOPNOTSUPP; 2115 } 2116 EXPORT_SYMBOL(sock_no_accept); 2117 2118 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2119 int *len, int peer) 2120 { 2121 return -EOPNOTSUPP; 2122 } 2123 EXPORT_SYMBOL(sock_no_getname); 2124 2125 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2126 { 2127 return 0; 2128 } 2129 EXPORT_SYMBOL(sock_no_poll); 2130 2131 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2132 { 2133 return -EOPNOTSUPP; 2134 } 2135 EXPORT_SYMBOL(sock_no_ioctl); 2136 2137 int sock_no_listen(struct socket *sock, int backlog) 2138 { 2139 return -EOPNOTSUPP; 2140 } 2141 EXPORT_SYMBOL(sock_no_listen); 2142 2143 int sock_no_shutdown(struct socket *sock, int how) 2144 { 2145 return -EOPNOTSUPP; 2146 } 2147 EXPORT_SYMBOL(sock_no_shutdown); 2148 2149 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2150 char __user *optval, unsigned int optlen) 2151 { 2152 return -EOPNOTSUPP; 2153 } 2154 EXPORT_SYMBOL(sock_no_setsockopt); 2155 2156 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2157 char __user *optval, int __user *optlen) 2158 { 2159 return -EOPNOTSUPP; 2160 } 2161 EXPORT_SYMBOL(sock_no_getsockopt); 2162 2163 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2164 size_t len) 2165 { 2166 return -EOPNOTSUPP; 2167 } 2168 EXPORT_SYMBOL(sock_no_sendmsg); 2169 2170 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2171 size_t len, int flags) 2172 { 2173 return -EOPNOTSUPP; 2174 } 2175 EXPORT_SYMBOL(sock_no_recvmsg); 2176 2177 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2178 { 2179 /* Mirror missing mmap method error code */ 2180 return -ENODEV; 2181 } 2182 EXPORT_SYMBOL(sock_no_mmap); 2183 2184 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2185 { 2186 ssize_t res; 2187 struct msghdr msg = {.msg_flags = flags}; 2188 struct kvec iov; 2189 char *kaddr = kmap(page); 2190 iov.iov_base = kaddr + offset; 2191 iov.iov_len = size; 2192 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2193 kunmap(page); 2194 return res; 2195 } 2196 EXPORT_SYMBOL(sock_no_sendpage); 2197 2198 /* 2199 * Default Socket Callbacks 2200 */ 2201 2202 static void sock_def_wakeup(struct sock *sk) 2203 { 2204 struct socket_wq *wq; 2205 2206 rcu_read_lock(); 2207 wq = rcu_dereference(sk->sk_wq); 2208 if (wq_has_sleeper(wq)) 2209 wake_up_interruptible_all(&wq->wait); 2210 rcu_read_unlock(); 2211 } 2212 2213 static void sock_def_error_report(struct sock *sk) 2214 { 2215 struct socket_wq *wq; 2216 2217 rcu_read_lock(); 2218 wq = rcu_dereference(sk->sk_wq); 2219 if (wq_has_sleeper(wq)) 2220 wake_up_interruptible_poll(&wq->wait, POLLERR); 2221 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2222 rcu_read_unlock(); 2223 } 2224 2225 static void sock_def_readable(struct sock *sk) 2226 { 2227 struct socket_wq *wq; 2228 2229 rcu_read_lock(); 2230 wq = rcu_dereference(sk->sk_wq); 2231 if (wq_has_sleeper(wq)) 2232 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2233 POLLRDNORM | POLLRDBAND); 2234 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2235 rcu_read_unlock(); 2236 } 2237 2238 static void sock_def_write_space(struct sock *sk) 2239 { 2240 struct socket_wq *wq; 2241 2242 rcu_read_lock(); 2243 2244 /* Do not wake up a writer until he can make "significant" 2245 * progress. --DaveM 2246 */ 2247 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2248 wq = rcu_dereference(sk->sk_wq); 2249 if (wq_has_sleeper(wq)) 2250 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2251 POLLWRNORM | POLLWRBAND); 2252 2253 /* Should agree with poll, otherwise some programs break */ 2254 if (sock_writeable(sk)) 2255 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2256 } 2257 2258 rcu_read_unlock(); 2259 } 2260 2261 static void sock_def_destruct(struct sock *sk) 2262 { 2263 kfree(sk->sk_protinfo); 2264 } 2265 2266 void sk_send_sigurg(struct sock *sk) 2267 { 2268 if (sk->sk_socket && sk->sk_socket->file) 2269 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2270 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2271 } 2272 EXPORT_SYMBOL(sk_send_sigurg); 2273 2274 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2275 unsigned long expires) 2276 { 2277 if (!mod_timer(timer, expires)) 2278 sock_hold(sk); 2279 } 2280 EXPORT_SYMBOL(sk_reset_timer); 2281 2282 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2283 { 2284 if (del_timer(timer)) 2285 __sock_put(sk); 2286 } 2287 EXPORT_SYMBOL(sk_stop_timer); 2288 2289 void sock_init_data(struct socket *sock, struct sock *sk) 2290 { 2291 skb_queue_head_init(&sk->sk_receive_queue); 2292 skb_queue_head_init(&sk->sk_write_queue); 2293 skb_queue_head_init(&sk->sk_error_queue); 2294 2295 sk->sk_send_head = NULL; 2296 2297 init_timer(&sk->sk_timer); 2298 2299 sk->sk_allocation = GFP_KERNEL; 2300 sk->sk_rcvbuf = sysctl_rmem_default; 2301 sk->sk_sndbuf = sysctl_wmem_default; 2302 sk->sk_state = TCP_CLOSE; 2303 sk_set_socket(sk, sock); 2304 2305 sock_set_flag(sk, SOCK_ZAPPED); 2306 2307 if (sock) { 2308 sk->sk_type = sock->type; 2309 sk->sk_wq = sock->wq; 2310 sock->sk = sk; 2311 } else 2312 sk->sk_wq = NULL; 2313 2314 spin_lock_init(&sk->sk_dst_lock); 2315 rwlock_init(&sk->sk_callback_lock); 2316 lockdep_set_class_and_name(&sk->sk_callback_lock, 2317 af_callback_keys + sk->sk_family, 2318 af_family_clock_key_strings[sk->sk_family]); 2319 2320 sk->sk_state_change = sock_def_wakeup; 2321 sk->sk_data_ready = sock_def_readable; 2322 sk->sk_write_space = sock_def_write_space; 2323 sk->sk_error_report = sock_def_error_report; 2324 sk->sk_destruct = sock_def_destruct; 2325 2326 sk->sk_frag.page = NULL; 2327 sk->sk_frag.offset = 0; 2328 sk->sk_peek_off = -1; 2329 2330 sk->sk_peer_pid = NULL; 2331 sk->sk_peer_cred = NULL; 2332 sk->sk_write_pending = 0; 2333 sk->sk_rcvlowat = 1; 2334 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2335 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2336 2337 sk->sk_stamp = ktime_set(-1L, 0); 2338 2339 #ifdef CONFIG_NET_RX_BUSY_POLL 2340 sk->sk_napi_id = 0; 2341 sk->sk_ll_usec = sysctl_net_busy_read; 2342 #endif 2343 2344 sk->sk_max_pacing_rate = ~0U; 2345 sk->sk_pacing_rate = ~0U; 2346 /* 2347 * Before updating sk_refcnt, we must commit prior changes to memory 2348 * (Documentation/RCU/rculist_nulls.txt for details) 2349 */ 2350 smp_wmb(); 2351 atomic_set(&sk->sk_refcnt, 1); 2352 atomic_set(&sk->sk_drops, 0); 2353 } 2354 EXPORT_SYMBOL(sock_init_data); 2355 2356 void lock_sock_nested(struct sock *sk, int subclass) 2357 { 2358 might_sleep(); 2359 spin_lock_bh(&sk->sk_lock.slock); 2360 if (sk->sk_lock.owned) 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, subclass, 0, _RET_IP_); 2368 local_bh_enable(); 2369 } 2370 EXPORT_SYMBOL(lock_sock_nested); 2371 2372 void release_sock(struct sock *sk) 2373 { 2374 /* 2375 * The sk_lock has mutex_unlock() semantics: 2376 */ 2377 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2378 2379 spin_lock_bh(&sk->sk_lock.slock); 2380 if (sk->sk_backlog.tail) 2381 __release_sock(sk); 2382 2383 /* Warning : release_cb() might need to release sk ownership, 2384 * ie call sock_release_ownership(sk) before us. 2385 */ 2386 if (sk->sk_prot->release_cb) 2387 sk->sk_prot->release_cb(sk); 2388 2389 sock_release_ownership(sk); 2390 if (waitqueue_active(&sk->sk_lock.wq)) 2391 wake_up(&sk->sk_lock.wq); 2392 spin_unlock_bh(&sk->sk_lock.slock); 2393 } 2394 EXPORT_SYMBOL(release_sock); 2395 2396 /** 2397 * lock_sock_fast - fast version of lock_sock 2398 * @sk: socket 2399 * 2400 * This version should be used for very small section, where process wont block 2401 * return false if fast path is taken 2402 * sk_lock.slock locked, owned = 0, BH disabled 2403 * return true if slow path is taken 2404 * sk_lock.slock unlocked, owned = 1, BH enabled 2405 */ 2406 bool lock_sock_fast(struct sock *sk) 2407 { 2408 might_sleep(); 2409 spin_lock_bh(&sk->sk_lock.slock); 2410 2411 if (!sk->sk_lock.owned) 2412 /* 2413 * Note : We must disable BH 2414 */ 2415 return false; 2416 2417 __lock_sock(sk); 2418 sk->sk_lock.owned = 1; 2419 spin_unlock(&sk->sk_lock.slock); 2420 /* 2421 * The sk_lock has mutex_lock() semantics here: 2422 */ 2423 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2424 local_bh_enable(); 2425 return true; 2426 } 2427 EXPORT_SYMBOL(lock_sock_fast); 2428 2429 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2430 { 2431 struct timeval tv; 2432 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2433 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2434 tv = ktime_to_timeval(sk->sk_stamp); 2435 if (tv.tv_sec == -1) 2436 return -ENOENT; 2437 if (tv.tv_sec == 0) { 2438 sk->sk_stamp = ktime_get_real(); 2439 tv = ktime_to_timeval(sk->sk_stamp); 2440 } 2441 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2442 } 2443 EXPORT_SYMBOL(sock_get_timestamp); 2444 2445 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2446 { 2447 struct timespec ts; 2448 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2449 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2450 ts = ktime_to_timespec(sk->sk_stamp); 2451 if (ts.tv_sec == -1) 2452 return -ENOENT; 2453 if (ts.tv_sec == 0) { 2454 sk->sk_stamp = ktime_get_real(); 2455 ts = ktime_to_timespec(sk->sk_stamp); 2456 } 2457 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2458 } 2459 EXPORT_SYMBOL(sock_get_timestampns); 2460 2461 void sock_enable_timestamp(struct sock *sk, int flag) 2462 { 2463 if (!sock_flag(sk, flag)) { 2464 unsigned long previous_flags = sk->sk_flags; 2465 2466 sock_set_flag(sk, flag); 2467 /* 2468 * we just set one of the two flags which require net 2469 * time stamping, but time stamping might have been on 2470 * already because of the other one 2471 */ 2472 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2473 net_enable_timestamp(); 2474 } 2475 } 2476 2477 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2478 int level, int type) 2479 { 2480 struct sock_exterr_skb *serr; 2481 struct sk_buff *skb; 2482 int copied, err; 2483 2484 err = -EAGAIN; 2485 skb = sock_dequeue_err_skb(sk); 2486 if (skb == NULL) 2487 goto out; 2488 2489 copied = skb->len; 2490 if (copied > len) { 2491 msg->msg_flags |= MSG_TRUNC; 2492 copied = len; 2493 } 2494 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2495 if (err) 2496 goto out_free_skb; 2497 2498 sock_recv_timestamp(msg, sk, skb); 2499 2500 serr = SKB_EXT_ERR(skb); 2501 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2502 2503 msg->msg_flags |= MSG_ERRQUEUE; 2504 err = copied; 2505 2506 out_free_skb: 2507 kfree_skb(skb); 2508 out: 2509 return err; 2510 } 2511 EXPORT_SYMBOL(sock_recv_errqueue); 2512 2513 /* 2514 * Get a socket option on an socket. 2515 * 2516 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2517 * asynchronous errors should be reported by getsockopt. We assume 2518 * this means if you specify SO_ERROR (otherwise whats the point of it). 2519 */ 2520 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2521 char __user *optval, int __user *optlen) 2522 { 2523 struct sock *sk = sock->sk; 2524 2525 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2526 } 2527 EXPORT_SYMBOL(sock_common_getsockopt); 2528 2529 #ifdef CONFIG_COMPAT 2530 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2531 char __user *optval, int __user *optlen) 2532 { 2533 struct sock *sk = sock->sk; 2534 2535 if (sk->sk_prot->compat_getsockopt != NULL) 2536 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2537 optval, optlen); 2538 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2539 } 2540 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2541 #endif 2542 2543 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2544 struct msghdr *msg, size_t size, int flags) 2545 { 2546 struct sock *sk = sock->sk; 2547 int addr_len = 0; 2548 int err; 2549 2550 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2551 flags & ~MSG_DONTWAIT, &addr_len); 2552 if (err >= 0) 2553 msg->msg_namelen = addr_len; 2554 return err; 2555 } 2556 EXPORT_SYMBOL(sock_common_recvmsg); 2557 2558 /* 2559 * Set socket options on an inet socket. 2560 */ 2561 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2562 char __user *optval, unsigned int optlen) 2563 { 2564 struct sock *sk = sock->sk; 2565 2566 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2567 } 2568 EXPORT_SYMBOL(sock_common_setsockopt); 2569 2570 #ifdef CONFIG_COMPAT 2571 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2572 char __user *optval, unsigned int optlen) 2573 { 2574 struct sock *sk = sock->sk; 2575 2576 if (sk->sk_prot->compat_setsockopt != NULL) 2577 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2578 optval, optlen); 2579 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2580 } 2581 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2582 #endif 2583 2584 void sk_common_release(struct sock *sk) 2585 { 2586 if (sk->sk_prot->destroy) 2587 sk->sk_prot->destroy(sk); 2588 2589 /* 2590 * Observation: when sock_common_release is called, processes have 2591 * no access to socket. But net still has. 2592 * Step one, detach it from networking: 2593 * 2594 * A. Remove from hash tables. 2595 */ 2596 2597 sk->sk_prot->unhash(sk); 2598 2599 /* 2600 * In this point socket cannot receive new packets, but it is possible 2601 * that some packets are in flight because some CPU runs receiver and 2602 * did hash table lookup before we unhashed socket. They will achieve 2603 * receive queue and will be purged by socket destructor. 2604 * 2605 * Also we still have packets pending on receive queue and probably, 2606 * our own packets waiting in device queues. sock_destroy will drain 2607 * receive queue, but transmitted packets will delay socket destruction 2608 * until the last reference will be released. 2609 */ 2610 2611 sock_orphan(sk); 2612 2613 xfrm_sk_free_policy(sk); 2614 2615 sk_refcnt_debug_release(sk); 2616 2617 if (sk->sk_frag.page) { 2618 put_page(sk->sk_frag.page); 2619 sk->sk_frag.page = NULL; 2620 } 2621 2622 sock_put(sk); 2623 } 2624 EXPORT_SYMBOL(sk_common_release); 2625 2626 #ifdef CONFIG_PROC_FS 2627 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2628 struct prot_inuse { 2629 int val[PROTO_INUSE_NR]; 2630 }; 2631 2632 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2633 2634 #ifdef CONFIG_NET_NS 2635 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2636 { 2637 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2638 } 2639 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2640 2641 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2642 { 2643 int cpu, idx = prot->inuse_idx; 2644 int res = 0; 2645 2646 for_each_possible_cpu(cpu) 2647 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2648 2649 return res >= 0 ? res : 0; 2650 } 2651 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2652 2653 static int __net_init sock_inuse_init_net(struct net *net) 2654 { 2655 net->core.inuse = alloc_percpu(struct prot_inuse); 2656 return net->core.inuse ? 0 : -ENOMEM; 2657 } 2658 2659 static void __net_exit sock_inuse_exit_net(struct net *net) 2660 { 2661 free_percpu(net->core.inuse); 2662 } 2663 2664 static struct pernet_operations net_inuse_ops = { 2665 .init = sock_inuse_init_net, 2666 .exit = sock_inuse_exit_net, 2667 }; 2668 2669 static __init int net_inuse_init(void) 2670 { 2671 if (register_pernet_subsys(&net_inuse_ops)) 2672 panic("Cannot initialize net inuse counters"); 2673 2674 return 0; 2675 } 2676 2677 core_initcall(net_inuse_init); 2678 #else 2679 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2680 2681 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2682 { 2683 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2684 } 2685 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2686 2687 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2688 { 2689 int cpu, idx = prot->inuse_idx; 2690 int res = 0; 2691 2692 for_each_possible_cpu(cpu) 2693 res += per_cpu(prot_inuse, cpu).val[idx]; 2694 2695 return res >= 0 ? res : 0; 2696 } 2697 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2698 #endif 2699 2700 static void assign_proto_idx(struct proto *prot) 2701 { 2702 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2703 2704 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2705 pr_err("PROTO_INUSE_NR exhausted\n"); 2706 return; 2707 } 2708 2709 set_bit(prot->inuse_idx, proto_inuse_idx); 2710 } 2711 2712 static void release_proto_idx(struct proto *prot) 2713 { 2714 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2715 clear_bit(prot->inuse_idx, proto_inuse_idx); 2716 } 2717 #else 2718 static inline void assign_proto_idx(struct proto *prot) 2719 { 2720 } 2721 2722 static inline void release_proto_idx(struct proto *prot) 2723 { 2724 } 2725 #endif 2726 2727 int proto_register(struct proto *prot, int alloc_slab) 2728 { 2729 if (alloc_slab) { 2730 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2731 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2732 NULL); 2733 2734 if (prot->slab == NULL) { 2735 pr_crit("%s: Can't create sock SLAB cache!\n", 2736 prot->name); 2737 goto out; 2738 } 2739 2740 if (prot->rsk_prot != NULL) { 2741 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2742 if (prot->rsk_prot->slab_name == NULL) 2743 goto out_free_sock_slab; 2744 2745 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2746 prot->rsk_prot->obj_size, 0, 2747 SLAB_HWCACHE_ALIGN, NULL); 2748 2749 if (prot->rsk_prot->slab == NULL) { 2750 pr_crit("%s: Can't create request sock SLAB cache!\n", 2751 prot->name); 2752 goto out_free_request_sock_slab_name; 2753 } 2754 } 2755 2756 if (prot->twsk_prot != NULL) { 2757 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2758 2759 if (prot->twsk_prot->twsk_slab_name == NULL) 2760 goto out_free_request_sock_slab; 2761 2762 prot->twsk_prot->twsk_slab = 2763 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2764 prot->twsk_prot->twsk_obj_size, 2765 0, 2766 SLAB_HWCACHE_ALIGN | 2767 prot->slab_flags, 2768 NULL); 2769 if (prot->twsk_prot->twsk_slab == NULL) 2770 goto out_free_timewait_sock_slab_name; 2771 } 2772 } 2773 2774 mutex_lock(&proto_list_mutex); 2775 list_add(&prot->node, &proto_list); 2776 assign_proto_idx(prot); 2777 mutex_unlock(&proto_list_mutex); 2778 return 0; 2779 2780 out_free_timewait_sock_slab_name: 2781 kfree(prot->twsk_prot->twsk_slab_name); 2782 out_free_request_sock_slab: 2783 if (prot->rsk_prot && prot->rsk_prot->slab) { 2784 kmem_cache_destroy(prot->rsk_prot->slab); 2785 prot->rsk_prot->slab = NULL; 2786 } 2787 out_free_request_sock_slab_name: 2788 if (prot->rsk_prot) 2789 kfree(prot->rsk_prot->slab_name); 2790 out_free_sock_slab: 2791 kmem_cache_destroy(prot->slab); 2792 prot->slab = NULL; 2793 out: 2794 return -ENOBUFS; 2795 } 2796 EXPORT_SYMBOL(proto_register); 2797 2798 void proto_unregister(struct proto *prot) 2799 { 2800 mutex_lock(&proto_list_mutex); 2801 release_proto_idx(prot); 2802 list_del(&prot->node); 2803 mutex_unlock(&proto_list_mutex); 2804 2805 if (prot->slab != NULL) { 2806 kmem_cache_destroy(prot->slab); 2807 prot->slab = NULL; 2808 } 2809 2810 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2811 kmem_cache_destroy(prot->rsk_prot->slab); 2812 kfree(prot->rsk_prot->slab_name); 2813 prot->rsk_prot->slab = NULL; 2814 } 2815 2816 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2817 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2818 kfree(prot->twsk_prot->twsk_slab_name); 2819 prot->twsk_prot->twsk_slab = NULL; 2820 } 2821 } 2822 EXPORT_SYMBOL(proto_unregister); 2823 2824 #ifdef CONFIG_PROC_FS 2825 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2826 __acquires(proto_list_mutex) 2827 { 2828 mutex_lock(&proto_list_mutex); 2829 return seq_list_start_head(&proto_list, *pos); 2830 } 2831 2832 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2833 { 2834 return seq_list_next(v, &proto_list, pos); 2835 } 2836 2837 static void proto_seq_stop(struct seq_file *seq, void *v) 2838 __releases(proto_list_mutex) 2839 { 2840 mutex_unlock(&proto_list_mutex); 2841 } 2842 2843 static char proto_method_implemented(const void *method) 2844 { 2845 return method == NULL ? 'n' : 'y'; 2846 } 2847 static long sock_prot_memory_allocated(struct proto *proto) 2848 { 2849 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2850 } 2851 2852 static char *sock_prot_memory_pressure(struct proto *proto) 2853 { 2854 return proto->memory_pressure != NULL ? 2855 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2856 } 2857 2858 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2859 { 2860 2861 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2862 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2863 proto->name, 2864 proto->obj_size, 2865 sock_prot_inuse_get(seq_file_net(seq), proto), 2866 sock_prot_memory_allocated(proto), 2867 sock_prot_memory_pressure(proto), 2868 proto->max_header, 2869 proto->slab == NULL ? "no" : "yes", 2870 module_name(proto->owner), 2871 proto_method_implemented(proto->close), 2872 proto_method_implemented(proto->connect), 2873 proto_method_implemented(proto->disconnect), 2874 proto_method_implemented(proto->accept), 2875 proto_method_implemented(proto->ioctl), 2876 proto_method_implemented(proto->init), 2877 proto_method_implemented(proto->destroy), 2878 proto_method_implemented(proto->shutdown), 2879 proto_method_implemented(proto->setsockopt), 2880 proto_method_implemented(proto->getsockopt), 2881 proto_method_implemented(proto->sendmsg), 2882 proto_method_implemented(proto->recvmsg), 2883 proto_method_implemented(proto->sendpage), 2884 proto_method_implemented(proto->bind), 2885 proto_method_implemented(proto->backlog_rcv), 2886 proto_method_implemented(proto->hash), 2887 proto_method_implemented(proto->unhash), 2888 proto_method_implemented(proto->get_port), 2889 proto_method_implemented(proto->enter_memory_pressure)); 2890 } 2891 2892 static int proto_seq_show(struct seq_file *seq, void *v) 2893 { 2894 if (v == &proto_list) 2895 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2896 "protocol", 2897 "size", 2898 "sockets", 2899 "memory", 2900 "press", 2901 "maxhdr", 2902 "slab", 2903 "module", 2904 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2905 else 2906 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2907 return 0; 2908 } 2909 2910 static const struct seq_operations proto_seq_ops = { 2911 .start = proto_seq_start, 2912 .next = proto_seq_next, 2913 .stop = proto_seq_stop, 2914 .show = proto_seq_show, 2915 }; 2916 2917 static int proto_seq_open(struct inode *inode, struct file *file) 2918 { 2919 return seq_open_net(inode, file, &proto_seq_ops, 2920 sizeof(struct seq_net_private)); 2921 } 2922 2923 static const struct file_operations proto_seq_fops = { 2924 .owner = THIS_MODULE, 2925 .open = proto_seq_open, 2926 .read = seq_read, 2927 .llseek = seq_lseek, 2928 .release = seq_release_net, 2929 }; 2930 2931 static __net_init int proto_init_net(struct net *net) 2932 { 2933 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2934 return -ENOMEM; 2935 2936 return 0; 2937 } 2938 2939 static __net_exit void proto_exit_net(struct net *net) 2940 { 2941 remove_proc_entry("protocols", net->proc_net); 2942 } 2943 2944 2945 static __net_initdata struct pernet_operations proto_net_ops = { 2946 .init = proto_init_net, 2947 .exit = proto_exit_net, 2948 }; 2949 2950 static int __init proto_init(void) 2951 { 2952 return register_pernet_subsys(&proto_net_ops); 2953 } 2954 2955 subsys_initcall(proto_init); 2956 2957 #endif /* PROC_FS */ 2958