1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Generic socket support routines. Memory allocators, socket lock/release 7 * handler for protocols to use and generic option handler. 8 * 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Florian La Roche, <flla@stud.uni-sb.de> 13 * Alan Cox, <A.Cox@swansea.ac.uk> 14 * 15 * Fixes: 16 * Alan Cox : Numerous verify_area() problems 17 * Alan Cox : Connecting on a connecting socket 18 * now returns an error for tcp. 19 * Alan Cox : sock->protocol is set correctly. 20 * and is not sometimes left as 0. 21 * Alan Cox : connect handles icmp errors on a 22 * connect properly. Unfortunately there 23 * is a restart syscall nasty there. I 24 * can't match BSD without hacking the C 25 * library. Ideas urgently sought! 26 * Alan Cox : Disallow bind() to addresses that are 27 * not ours - especially broadcast ones!! 28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) 29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, 30 * instead they leave that for the DESTROY timer. 31 * Alan Cox : Clean up error flag in accept 32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer 33 * was buggy. Put a remove_sock() in the handler 34 * for memory when we hit 0. Also altered the timer 35 * code. The ACK stuff can wait and needs major 36 * TCP layer surgery. 37 * Alan Cox : Fixed TCP ack bug, removed remove sock 38 * and fixed timer/inet_bh race. 39 * Alan Cox : Added zapped flag for TCP 40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code 41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb 42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources 43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. 44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... 45 * Rick Sladkey : Relaxed UDP rules for matching packets. 46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support 47 * Pauline Middelink : identd support 48 * Alan Cox : Fixed connect() taking signals I think. 49 * Alan Cox : SO_LINGER supported 50 * Alan Cox : Error reporting fixes 51 * Anonymous : inet_create tidied up (sk->reuse setting) 52 * Alan Cox : inet sockets don't set sk->type! 53 * Alan Cox : Split socket option code 54 * Alan Cox : Callbacks 55 * Alan Cox : Nagle flag for Charles & Johannes stuff 56 * Alex : Removed restriction on inet fioctl 57 * Alan Cox : Splitting INET from NET core 58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() 59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code 60 * Alan Cox : Split IP from generic code 61 * Alan Cox : New kfree_skbmem() 62 * Alan Cox : Make SO_DEBUG superuser only. 63 * Alan Cox : Allow anyone to clear SO_DEBUG 64 * (compatibility fix) 65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. 66 * Alan Cox : Allocator for a socket is settable. 67 * Alan Cox : SO_ERROR includes soft errors. 68 * Alan Cox : Allow NULL arguments on some SO_ opts 69 * Alan Cox : Generic socket allocation to make hooks 70 * easier (suggested by Craig Metz). 71 * Michael Pall : SO_ERROR returns positive errno again 72 * Steve Whitehouse: Added default destructor to free 73 * protocol private data. 74 * Steve Whitehouse: Added various other default routines 75 * common to several socket families. 76 * Chris Evans : Call suser() check last on F_SETOWN 77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. 78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() 79 * Andi Kleen : Fix write_space callback 80 * Chris Evans : Security fixes - signedness again 81 * Arnaldo C. Melo : cleanups, use skb_queue_purge 82 * 83 * To Fix: 84 * 85 * 86 * This program is free software; you can redistribute it and/or 87 * modify it under the terms of the GNU General Public License 88 * as published by the Free Software Foundation; either version 89 * 2 of the License, or (at your option) any later version. 90 */ 91 92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 93 94 #include <linux/capability.h> 95 #include <linux/errno.h> 96 #include <linux/errqueue.h> 97 #include <linux/types.h> 98 #include <linux/socket.h> 99 #include <linux/in.h> 100 #include <linux/kernel.h> 101 #include <linux/module.h> 102 #include <linux/proc_fs.h> 103 #include <linux/seq_file.h> 104 #include <linux/sched.h> 105 #include <linux/timer.h> 106 #include <linux/string.h> 107 #include <linux/sockios.h> 108 #include <linux/net.h> 109 #include <linux/mm.h> 110 #include <linux/slab.h> 111 #include <linux/interrupt.h> 112 #include <linux/poll.h> 113 #include <linux/tcp.h> 114 #include <linux/init.h> 115 #include <linux/highmem.h> 116 #include <linux/user_namespace.h> 117 #include <linux/static_key.h> 118 #include <linux/memcontrol.h> 119 #include <linux/prefetch.h> 120 121 #include <asm/uaccess.h> 122 123 #include <linux/netdevice.h> 124 #include <net/protocol.h> 125 #include <linux/skbuff.h> 126 #include <net/net_namespace.h> 127 #include <net/request_sock.h> 128 #include <net/sock.h> 129 #include <linux/net_tstamp.h> 130 #include <net/xfrm.h> 131 #include <linux/ipsec.h> 132 #include <net/cls_cgroup.h> 133 #include <net/netprio_cgroup.h> 134 135 #include <linux/filter.h> 136 137 #include <trace/events/sock.h> 138 139 #ifdef CONFIG_INET 140 #include <net/tcp.h> 141 #endif 142 143 #include <net/busy_poll.h> 144 145 static DEFINE_MUTEX(proto_list_mutex); 146 static LIST_HEAD(proto_list); 147 148 /** 149 * sk_ns_capable - General socket capability test 150 * @sk: Socket to use a capability on or through 151 * @user_ns: The user namespace of the capability to use 152 * @cap: The capability to use 153 * 154 * Test to see if the opener of the socket had when the socket was 155 * created and the current process has the capability @cap in the user 156 * namespace @user_ns. 157 */ 158 bool sk_ns_capable(const struct sock *sk, 159 struct user_namespace *user_ns, int cap) 160 { 161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 162 ns_capable(user_ns, cap); 163 } 164 EXPORT_SYMBOL(sk_ns_capable); 165 166 /** 167 * sk_capable - Socket global capability test 168 * @sk: Socket to use a capability on or through 169 * @cap: The global capability to use 170 * 171 * Test to see if the opener of the socket had when the socket was 172 * created and the current process has the capability @cap in all user 173 * namespaces. 174 */ 175 bool sk_capable(const struct sock *sk, int cap) 176 { 177 return sk_ns_capable(sk, &init_user_ns, cap); 178 } 179 EXPORT_SYMBOL(sk_capable); 180 181 /** 182 * sk_net_capable - Network namespace socket capability test 183 * @sk: Socket to use a capability on or through 184 * @cap: The capability to use 185 * 186 * Test to see if the opener of the socket had when the socket was created 187 * and the current process has the capability @cap over the network namespace 188 * the socket is a member of. 189 */ 190 bool sk_net_capable(const struct sock *sk, int cap) 191 { 192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 193 } 194 EXPORT_SYMBOL(sk_net_capable); 195 196 197 #ifdef CONFIG_MEMCG_KMEM 198 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 199 { 200 struct proto *proto; 201 int ret = 0; 202 203 mutex_lock(&proto_list_mutex); 204 list_for_each_entry(proto, &proto_list, node) { 205 if (proto->init_cgroup) { 206 ret = proto->init_cgroup(memcg, ss); 207 if (ret) 208 goto out; 209 } 210 } 211 212 mutex_unlock(&proto_list_mutex); 213 return ret; 214 out: 215 list_for_each_entry_continue_reverse(proto, &proto_list, node) 216 if (proto->destroy_cgroup) 217 proto->destroy_cgroup(memcg); 218 mutex_unlock(&proto_list_mutex); 219 return ret; 220 } 221 222 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 223 { 224 struct proto *proto; 225 226 mutex_lock(&proto_list_mutex); 227 list_for_each_entry_reverse(proto, &proto_list, node) 228 if (proto->destroy_cgroup) 229 proto->destroy_cgroup(memcg); 230 mutex_unlock(&proto_list_mutex); 231 } 232 #endif 233 234 /* 235 * Each address family might have different locking rules, so we have 236 * one slock key per address family: 237 */ 238 static struct lock_class_key af_family_keys[AF_MAX]; 239 static struct lock_class_key af_family_slock_keys[AF_MAX]; 240 241 #if defined(CONFIG_MEMCG_KMEM) 242 struct static_key memcg_socket_limit_enabled; 243 EXPORT_SYMBOL(memcg_socket_limit_enabled); 244 #endif 245 246 /* 247 * Make lock validator output more readable. (we pre-construct these 248 * strings build-time, so that runtime initialization of socket 249 * locks is fast): 250 */ 251 static const char *const af_family_key_strings[AF_MAX+1] = { 252 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 253 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 254 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 255 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 256 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 257 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 258 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 259 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 260 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 261 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 262 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 263 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 264 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 265 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX" 266 }; 267 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 268 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 269 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 270 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 271 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 272 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 273 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 274 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 275 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 276 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 277 "slock-27" , "slock-28" , "slock-AF_CAN" , 278 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 279 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 280 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 281 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX" 282 }; 283 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 284 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 285 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 286 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 287 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 288 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 289 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 290 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 291 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 292 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 293 "clock-27" , "clock-28" , "clock-AF_CAN" , 294 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 295 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 296 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 297 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX" 298 }; 299 300 /* 301 * sk_callback_lock locking rules are per-address-family, 302 * so split the lock classes by using a per-AF key: 303 */ 304 static struct lock_class_key af_callback_keys[AF_MAX]; 305 306 /* Take into consideration the size of the struct sk_buff overhead in the 307 * determination of these values, since that is non-constant across 308 * platforms. This makes socket queueing behavior and performance 309 * not depend upon such differences. 310 */ 311 #define _SK_MEM_PACKETS 256 312 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 313 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 314 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 315 316 /* Run time adjustable parameters. */ 317 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 318 EXPORT_SYMBOL(sysctl_wmem_max); 319 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 320 EXPORT_SYMBOL(sysctl_rmem_max); 321 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 322 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 323 324 /* Maximal space eaten by iovec or ancillary data plus some space */ 325 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 326 EXPORT_SYMBOL(sysctl_optmem_max); 327 328 int sysctl_tstamp_allow_data __read_mostly = 1; 329 330 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 331 EXPORT_SYMBOL_GPL(memalloc_socks); 332 333 /** 334 * sk_set_memalloc - sets %SOCK_MEMALLOC 335 * @sk: socket to set it on 336 * 337 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 338 * It's the responsibility of the admin to adjust min_free_kbytes 339 * to meet the requirements 340 */ 341 void sk_set_memalloc(struct sock *sk) 342 { 343 sock_set_flag(sk, SOCK_MEMALLOC); 344 sk->sk_allocation |= __GFP_MEMALLOC; 345 static_key_slow_inc(&memalloc_socks); 346 } 347 EXPORT_SYMBOL_GPL(sk_set_memalloc); 348 349 void sk_clear_memalloc(struct sock *sk) 350 { 351 sock_reset_flag(sk, SOCK_MEMALLOC); 352 sk->sk_allocation &= ~__GFP_MEMALLOC; 353 static_key_slow_dec(&memalloc_socks); 354 355 /* 356 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 357 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 358 * it has rmem allocations there is a risk that the user of the 359 * socket cannot make forward progress due to exceeding the rmem 360 * limits. By rights, sk_clear_memalloc() should only be called 361 * on sockets being torn down but warn and reset the accounting if 362 * that assumption breaks. 363 */ 364 if (WARN_ON(sk->sk_forward_alloc)) 365 sk_mem_reclaim(sk); 366 } 367 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 368 369 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 370 { 371 int ret; 372 unsigned long pflags = current->flags; 373 374 /* these should have been dropped before queueing */ 375 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 376 377 current->flags |= PF_MEMALLOC; 378 ret = sk->sk_backlog_rcv(sk, skb); 379 tsk_restore_flags(current, pflags, PF_MEMALLOC); 380 381 return ret; 382 } 383 EXPORT_SYMBOL(__sk_backlog_rcv); 384 385 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 386 { 387 struct timeval tv; 388 389 if (optlen < sizeof(tv)) 390 return -EINVAL; 391 if (copy_from_user(&tv, optval, sizeof(tv))) 392 return -EFAULT; 393 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 394 return -EDOM; 395 396 if (tv.tv_sec < 0) { 397 static int warned __read_mostly; 398 399 *timeo_p = 0; 400 if (warned < 10 && net_ratelimit()) { 401 warned++; 402 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 403 __func__, current->comm, task_pid_nr(current)); 404 } 405 return 0; 406 } 407 *timeo_p = MAX_SCHEDULE_TIMEOUT; 408 if (tv.tv_sec == 0 && tv.tv_usec == 0) 409 return 0; 410 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 411 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 412 return 0; 413 } 414 415 static void sock_warn_obsolete_bsdism(const char *name) 416 { 417 static int warned; 418 static char warncomm[TASK_COMM_LEN]; 419 if (strcmp(warncomm, current->comm) && warned < 5) { 420 strcpy(warncomm, current->comm); 421 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 422 warncomm, name); 423 warned++; 424 } 425 } 426 427 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 428 429 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 430 { 431 if (sk->sk_flags & flags) { 432 sk->sk_flags &= ~flags; 433 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 434 net_disable_timestamp(); 435 } 436 } 437 438 439 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 440 { 441 int err; 442 unsigned long flags; 443 struct sk_buff_head *list = &sk->sk_receive_queue; 444 445 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 446 atomic_inc(&sk->sk_drops); 447 trace_sock_rcvqueue_full(sk, skb); 448 return -ENOMEM; 449 } 450 451 err = sk_filter(sk, skb); 452 if (err) 453 return err; 454 455 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 456 atomic_inc(&sk->sk_drops); 457 return -ENOBUFS; 458 } 459 460 skb->dev = NULL; 461 skb_set_owner_r(skb, sk); 462 463 /* we escape from rcu protected region, make sure we dont leak 464 * a norefcounted dst 465 */ 466 skb_dst_force(skb); 467 468 spin_lock_irqsave(&list->lock, flags); 469 sock_skb_set_dropcount(sk, skb); 470 __skb_queue_tail(list, skb); 471 spin_unlock_irqrestore(&list->lock, flags); 472 473 if (!sock_flag(sk, SOCK_DEAD)) 474 sk->sk_data_ready(sk); 475 return 0; 476 } 477 EXPORT_SYMBOL(sock_queue_rcv_skb); 478 479 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 480 { 481 int rc = NET_RX_SUCCESS; 482 483 if (sk_filter(sk, skb)) 484 goto discard_and_relse; 485 486 skb->dev = NULL; 487 488 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 489 atomic_inc(&sk->sk_drops); 490 goto discard_and_relse; 491 } 492 if (nested) 493 bh_lock_sock_nested(sk); 494 else 495 bh_lock_sock(sk); 496 if (!sock_owned_by_user(sk)) { 497 /* 498 * trylock + unlock semantics: 499 */ 500 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 501 502 rc = sk_backlog_rcv(sk, skb); 503 504 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 505 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 506 bh_unlock_sock(sk); 507 atomic_inc(&sk->sk_drops); 508 goto discard_and_relse; 509 } 510 511 bh_unlock_sock(sk); 512 out: 513 sock_put(sk); 514 return rc; 515 discard_and_relse: 516 kfree_skb(skb); 517 goto out; 518 } 519 EXPORT_SYMBOL(sk_receive_skb); 520 521 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 522 { 523 struct dst_entry *dst = __sk_dst_get(sk); 524 525 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 526 sk_tx_queue_clear(sk); 527 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 528 dst_release(dst); 529 return NULL; 530 } 531 532 return dst; 533 } 534 EXPORT_SYMBOL(__sk_dst_check); 535 536 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 537 { 538 struct dst_entry *dst = sk_dst_get(sk); 539 540 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 541 sk_dst_reset(sk); 542 dst_release(dst); 543 return NULL; 544 } 545 546 return dst; 547 } 548 EXPORT_SYMBOL(sk_dst_check); 549 550 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 551 int optlen) 552 { 553 int ret = -ENOPROTOOPT; 554 #ifdef CONFIG_NETDEVICES 555 struct net *net = sock_net(sk); 556 char devname[IFNAMSIZ]; 557 int index; 558 559 /* Sorry... */ 560 ret = -EPERM; 561 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 562 goto out; 563 564 ret = -EINVAL; 565 if (optlen < 0) 566 goto out; 567 568 /* Bind this socket to a particular device like "eth0", 569 * as specified in the passed interface name. If the 570 * name is "" or the option length is zero the socket 571 * is not bound. 572 */ 573 if (optlen > IFNAMSIZ - 1) 574 optlen = IFNAMSIZ - 1; 575 memset(devname, 0, sizeof(devname)); 576 577 ret = -EFAULT; 578 if (copy_from_user(devname, optval, optlen)) 579 goto out; 580 581 index = 0; 582 if (devname[0] != '\0') { 583 struct net_device *dev; 584 585 rcu_read_lock(); 586 dev = dev_get_by_name_rcu(net, devname); 587 if (dev) 588 index = dev->ifindex; 589 rcu_read_unlock(); 590 ret = -ENODEV; 591 if (!dev) 592 goto out; 593 } 594 595 lock_sock(sk); 596 sk->sk_bound_dev_if = index; 597 sk_dst_reset(sk); 598 release_sock(sk); 599 600 ret = 0; 601 602 out: 603 #endif 604 605 return ret; 606 } 607 608 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 609 int __user *optlen, int len) 610 { 611 int ret = -ENOPROTOOPT; 612 #ifdef CONFIG_NETDEVICES 613 struct net *net = sock_net(sk); 614 char devname[IFNAMSIZ]; 615 616 if (sk->sk_bound_dev_if == 0) { 617 len = 0; 618 goto zero; 619 } 620 621 ret = -EINVAL; 622 if (len < IFNAMSIZ) 623 goto out; 624 625 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 626 if (ret) 627 goto out; 628 629 len = strlen(devname) + 1; 630 631 ret = -EFAULT; 632 if (copy_to_user(optval, devname, len)) 633 goto out; 634 635 zero: 636 ret = -EFAULT; 637 if (put_user(len, optlen)) 638 goto out; 639 640 ret = 0; 641 642 out: 643 #endif 644 645 return ret; 646 } 647 648 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 649 { 650 if (valbool) 651 sock_set_flag(sk, bit); 652 else 653 sock_reset_flag(sk, bit); 654 } 655 656 bool sk_mc_loop(struct sock *sk) 657 { 658 if (dev_recursion_level()) 659 return false; 660 if (!sk) 661 return true; 662 switch (sk->sk_family) { 663 case AF_INET: 664 return inet_sk(sk)->mc_loop; 665 #if IS_ENABLED(CONFIG_IPV6) 666 case AF_INET6: 667 return inet6_sk(sk)->mc_loop; 668 #endif 669 } 670 WARN_ON(1); 671 return true; 672 } 673 EXPORT_SYMBOL(sk_mc_loop); 674 675 /* 676 * This is meant for all protocols to use and covers goings on 677 * at the socket level. Everything here is generic. 678 */ 679 680 int sock_setsockopt(struct socket *sock, int level, int optname, 681 char __user *optval, unsigned int optlen) 682 { 683 struct sock *sk = sock->sk; 684 int val; 685 int valbool; 686 struct linger ling; 687 int ret = 0; 688 689 /* 690 * Options without arguments 691 */ 692 693 if (optname == SO_BINDTODEVICE) 694 return sock_setbindtodevice(sk, optval, optlen); 695 696 if (optlen < sizeof(int)) 697 return -EINVAL; 698 699 if (get_user(val, (int __user *)optval)) 700 return -EFAULT; 701 702 valbool = val ? 1 : 0; 703 704 lock_sock(sk); 705 706 switch (optname) { 707 case SO_DEBUG: 708 if (val && !capable(CAP_NET_ADMIN)) 709 ret = -EACCES; 710 else 711 sock_valbool_flag(sk, SOCK_DBG, valbool); 712 break; 713 case SO_REUSEADDR: 714 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 715 break; 716 case SO_REUSEPORT: 717 sk->sk_reuseport = valbool; 718 break; 719 case SO_TYPE: 720 case SO_PROTOCOL: 721 case SO_DOMAIN: 722 case SO_ERROR: 723 ret = -ENOPROTOOPT; 724 break; 725 case SO_DONTROUTE: 726 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 727 break; 728 case SO_BROADCAST: 729 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 730 break; 731 case SO_SNDBUF: 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_wmem_max); 738 set_sndbuf: 739 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 740 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 741 /* Wake up sending tasks if we upped the value. */ 742 sk->sk_write_space(sk); 743 break; 744 745 case SO_SNDBUFFORCE: 746 if (!capable(CAP_NET_ADMIN)) { 747 ret = -EPERM; 748 break; 749 } 750 goto set_sndbuf; 751 752 case SO_RCVBUF: 753 /* Don't error on this BSD doesn't and if you think 754 * about it this is right. Otherwise apps have to 755 * play 'guess the biggest size' games. RCVBUF/SNDBUF 756 * are treated in BSD as hints 757 */ 758 val = min_t(u32, val, sysctl_rmem_max); 759 set_rcvbuf: 760 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 761 /* 762 * We double it on the way in to account for 763 * "struct sk_buff" etc. overhead. Applications 764 * assume that the SO_RCVBUF setting they make will 765 * allow that much actual data to be received on that 766 * socket. 767 * 768 * Applications are unaware that "struct sk_buff" and 769 * other overheads allocate from the receive buffer 770 * during socket buffer allocation. 771 * 772 * And after considering the possible alternatives, 773 * returning the value we actually used in getsockopt 774 * is the most desirable behavior. 775 */ 776 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 777 break; 778 779 case SO_RCVBUFFORCE: 780 if (!capable(CAP_NET_ADMIN)) { 781 ret = -EPERM; 782 break; 783 } 784 goto set_rcvbuf; 785 786 case SO_KEEPALIVE: 787 #ifdef CONFIG_INET 788 if (sk->sk_protocol == IPPROTO_TCP && 789 sk->sk_type == SOCK_STREAM) 790 tcp_set_keepalive(sk, valbool); 791 #endif 792 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 793 break; 794 795 case SO_OOBINLINE: 796 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 797 break; 798 799 case SO_NO_CHECK: 800 sk->sk_no_check_tx = valbool; 801 break; 802 803 case SO_PRIORITY: 804 if ((val >= 0 && val <= 6) || 805 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 806 sk->sk_priority = val; 807 else 808 ret = -EPERM; 809 break; 810 811 case SO_LINGER: 812 if (optlen < sizeof(ling)) { 813 ret = -EINVAL; /* 1003.1g */ 814 break; 815 } 816 if (copy_from_user(&ling, optval, sizeof(ling))) { 817 ret = -EFAULT; 818 break; 819 } 820 if (!ling.l_onoff) 821 sock_reset_flag(sk, SOCK_LINGER); 822 else { 823 #if (BITS_PER_LONG == 32) 824 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 825 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 826 else 827 #endif 828 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 829 sock_set_flag(sk, SOCK_LINGER); 830 } 831 break; 832 833 case SO_BSDCOMPAT: 834 sock_warn_obsolete_bsdism("setsockopt"); 835 break; 836 837 case SO_PASSCRED: 838 if (valbool) 839 set_bit(SOCK_PASSCRED, &sock->flags); 840 else 841 clear_bit(SOCK_PASSCRED, &sock->flags); 842 break; 843 844 case SO_TIMESTAMP: 845 case SO_TIMESTAMPNS: 846 if (valbool) { 847 if (optname == SO_TIMESTAMP) 848 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 849 else 850 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 851 sock_set_flag(sk, SOCK_RCVTSTAMP); 852 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 853 } else { 854 sock_reset_flag(sk, SOCK_RCVTSTAMP); 855 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 856 } 857 break; 858 859 case SO_TIMESTAMPING: 860 if (val & ~SOF_TIMESTAMPING_MASK) { 861 ret = -EINVAL; 862 break; 863 } 864 865 if (val & SOF_TIMESTAMPING_OPT_ID && 866 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 867 if (sk->sk_protocol == IPPROTO_TCP) { 868 if (sk->sk_state != TCP_ESTABLISHED) { 869 ret = -EINVAL; 870 break; 871 } 872 sk->sk_tskey = tcp_sk(sk)->snd_una; 873 } else { 874 sk->sk_tskey = 0; 875 } 876 } 877 sk->sk_tsflags = val; 878 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 879 sock_enable_timestamp(sk, 880 SOCK_TIMESTAMPING_RX_SOFTWARE); 881 else 882 sock_disable_timestamp(sk, 883 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 884 break; 885 886 case SO_RCVLOWAT: 887 if (val < 0) 888 val = INT_MAX; 889 sk->sk_rcvlowat = val ? : 1; 890 break; 891 892 case SO_RCVTIMEO: 893 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 894 break; 895 896 case SO_SNDTIMEO: 897 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 898 break; 899 900 case SO_ATTACH_FILTER: 901 ret = -EINVAL; 902 if (optlen == sizeof(struct sock_fprog)) { 903 struct sock_fprog fprog; 904 905 ret = -EFAULT; 906 if (copy_from_user(&fprog, optval, sizeof(fprog))) 907 break; 908 909 ret = sk_attach_filter(&fprog, sk); 910 } 911 break; 912 913 case SO_ATTACH_BPF: 914 ret = -EINVAL; 915 if (optlen == sizeof(u32)) { 916 u32 ufd; 917 918 ret = -EFAULT; 919 if (copy_from_user(&ufd, optval, sizeof(ufd))) 920 break; 921 922 ret = sk_attach_bpf(ufd, sk); 923 } 924 break; 925 926 case SO_DETACH_FILTER: 927 ret = sk_detach_filter(sk); 928 break; 929 930 case SO_LOCK_FILTER: 931 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 932 ret = -EPERM; 933 else 934 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 935 break; 936 937 case SO_PASSSEC: 938 if (valbool) 939 set_bit(SOCK_PASSSEC, &sock->flags); 940 else 941 clear_bit(SOCK_PASSSEC, &sock->flags); 942 break; 943 case SO_MARK: 944 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 945 ret = -EPERM; 946 else 947 sk->sk_mark = val; 948 break; 949 950 case SO_RXQ_OVFL: 951 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 952 break; 953 954 case SO_WIFI_STATUS: 955 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 956 break; 957 958 case SO_PEEK_OFF: 959 if (sock->ops->set_peek_off) 960 ret = sock->ops->set_peek_off(sk, val); 961 else 962 ret = -EOPNOTSUPP; 963 break; 964 965 case SO_NOFCS: 966 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 967 break; 968 969 case SO_SELECT_ERR_QUEUE: 970 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 971 break; 972 973 #ifdef CONFIG_NET_RX_BUSY_POLL 974 case SO_BUSY_POLL: 975 /* allow unprivileged users to decrease the value */ 976 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 977 ret = -EPERM; 978 else { 979 if (val < 0) 980 ret = -EINVAL; 981 else 982 sk->sk_ll_usec = val; 983 } 984 break; 985 #endif 986 987 case SO_MAX_PACING_RATE: 988 sk->sk_max_pacing_rate = val; 989 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 990 sk->sk_max_pacing_rate); 991 break; 992 993 default: 994 ret = -ENOPROTOOPT; 995 break; 996 } 997 release_sock(sk); 998 return ret; 999 } 1000 EXPORT_SYMBOL(sock_setsockopt); 1001 1002 1003 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1004 struct ucred *ucred) 1005 { 1006 ucred->pid = pid_vnr(pid); 1007 ucred->uid = ucred->gid = -1; 1008 if (cred) { 1009 struct user_namespace *current_ns = current_user_ns(); 1010 1011 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1012 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1013 } 1014 } 1015 1016 int sock_getsockopt(struct socket *sock, int level, int optname, 1017 char __user *optval, int __user *optlen) 1018 { 1019 struct sock *sk = sock->sk; 1020 1021 union { 1022 int val; 1023 struct linger ling; 1024 struct timeval tm; 1025 } v; 1026 1027 int lv = sizeof(int); 1028 int len; 1029 1030 if (get_user(len, optlen)) 1031 return -EFAULT; 1032 if (len < 0) 1033 return -EINVAL; 1034 1035 memset(&v, 0, sizeof(v)); 1036 1037 switch (optname) { 1038 case SO_DEBUG: 1039 v.val = sock_flag(sk, SOCK_DBG); 1040 break; 1041 1042 case SO_DONTROUTE: 1043 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1044 break; 1045 1046 case SO_BROADCAST: 1047 v.val = sock_flag(sk, SOCK_BROADCAST); 1048 break; 1049 1050 case SO_SNDBUF: 1051 v.val = sk->sk_sndbuf; 1052 break; 1053 1054 case SO_RCVBUF: 1055 v.val = sk->sk_rcvbuf; 1056 break; 1057 1058 case SO_REUSEADDR: 1059 v.val = sk->sk_reuse; 1060 break; 1061 1062 case SO_REUSEPORT: 1063 v.val = sk->sk_reuseport; 1064 break; 1065 1066 case SO_KEEPALIVE: 1067 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1068 break; 1069 1070 case SO_TYPE: 1071 v.val = sk->sk_type; 1072 break; 1073 1074 case SO_PROTOCOL: 1075 v.val = sk->sk_protocol; 1076 break; 1077 1078 case SO_DOMAIN: 1079 v.val = sk->sk_family; 1080 break; 1081 1082 case SO_ERROR: 1083 v.val = -sock_error(sk); 1084 if (v.val == 0) 1085 v.val = xchg(&sk->sk_err_soft, 0); 1086 break; 1087 1088 case SO_OOBINLINE: 1089 v.val = sock_flag(sk, SOCK_URGINLINE); 1090 break; 1091 1092 case SO_NO_CHECK: 1093 v.val = sk->sk_no_check_tx; 1094 break; 1095 1096 case SO_PRIORITY: 1097 v.val = sk->sk_priority; 1098 break; 1099 1100 case SO_LINGER: 1101 lv = sizeof(v.ling); 1102 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1103 v.ling.l_linger = sk->sk_lingertime / HZ; 1104 break; 1105 1106 case SO_BSDCOMPAT: 1107 sock_warn_obsolete_bsdism("getsockopt"); 1108 break; 1109 1110 case SO_TIMESTAMP: 1111 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1112 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1113 break; 1114 1115 case SO_TIMESTAMPNS: 1116 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1117 break; 1118 1119 case SO_TIMESTAMPING: 1120 v.val = sk->sk_tsflags; 1121 break; 1122 1123 case SO_RCVTIMEO: 1124 lv = sizeof(struct timeval); 1125 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1126 v.tm.tv_sec = 0; 1127 v.tm.tv_usec = 0; 1128 } else { 1129 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1130 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1131 } 1132 break; 1133 1134 case SO_SNDTIMEO: 1135 lv = sizeof(struct timeval); 1136 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1137 v.tm.tv_sec = 0; 1138 v.tm.tv_usec = 0; 1139 } else { 1140 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1141 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1142 } 1143 break; 1144 1145 case SO_RCVLOWAT: 1146 v.val = sk->sk_rcvlowat; 1147 break; 1148 1149 case SO_SNDLOWAT: 1150 v.val = 1; 1151 break; 1152 1153 case SO_PASSCRED: 1154 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1155 break; 1156 1157 case SO_PEERCRED: 1158 { 1159 struct ucred peercred; 1160 if (len > sizeof(peercred)) 1161 len = sizeof(peercred); 1162 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1163 if (copy_to_user(optval, &peercred, len)) 1164 return -EFAULT; 1165 goto lenout; 1166 } 1167 1168 case SO_PEERNAME: 1169 { 1170 char address[128]; 1171 1172 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1173 return -ENOTCONN; 1174 if (lv < len) 1175 return -EINVAL; 1176 if (copy_to_user(optval, address, len)) 1177 return -EFAULT; 1178 goto lenout; 1179 } 1180 1181 /* Dubious BSD thing... Probably nobody even uses it, but 1182 * the UNIX standard wants it for whatever reason... -DaveM 1183 */ 1184 case SO_ACCEPTCONN: 1185 v.val = sk->sk_state == TCP_LISTEN; 1186 break; 1187 1188 case SO_PASSSEC: 1189 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1190 break; 1191 1192 case SO_PEERSEC: 1193 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1194 1195 case SO_MARK: 1196 v.val = sk->sk_mark; 1197 break; 1198 1199 case SO_RXQ_OVFL: 1200 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1201 break; 1202 1203 case SO_WIFI_STATUS: 1204 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1205 break; 1206 1207 case SO_PEEK_OFF: 1208 if (!sock->ops->set_peek_off) 1209 return -EOPNOTSUPP; 1210 1211 v.val = sk->sk_peek_off; 1212 break; 1213 case SO_NOFCS: 1214 v.val = sock_flag(sk, SOCK_NOFCS); 1215 break; 1216 1217 case SO_BINDTODEVICE: 1218 return sock_getbindtodevice(sk, optval, optlen, len); 1219 1220 case SO_GET_FILTER: 1221 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1222 if (len < 0) 1223 return len; 1224 1225 goto lenout; 1226 1227 case SO_LOCK_FILTER: 1228 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1229 break; 1230 1231 case SO_BPF_EXTENSIONS: 1232 v.val = bpf_tell_extensions(); 1233 break; 1234 1235 case SO_SELECT_ERR_QUEUE: 1236 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1237 break; 1238 1239 #ifdef CONFIG_NET_RX_BUSY_POLL 1240 case SO_BUSY_POLL: 1241 v.val = sk->sk_ll_usec; 1242 break; 1243 #endif 1244 1245 case SO_MAX_PACING_RATE: 1246 v.val = sk->sk_max_pacing_rate; 1247 break; 1248 1249 case SO_INCOMING_CPU: 1250 v.val = sk->sk_incoming_cpu; 1251 break; 1252 1253 default: 1254 /* We implement the SO_SNDLOWAT etc to not be settable 1255 * (1003.1g 7). 1256 */ 1257 return -ENOPROTOOPT; 1258 } 1259 1260 if (len > lv) 1261 len = lv; 1262 if (copy_to_user(optval, &v, len)) 1263 return -EFAULT; 1264 lenout: 1265 if (put_user(len, optlen)) 1266 return -EFAULT; 1267 return 0; 1268 } 1269 1270 /* 1271 * Initialize an sk_lock. 1272 * 1273 * (We also register the sk_lock with the lock validator.) 1274 */ 1275 static inline void sock_lock_init(struct sock *sk) 1276 { 1277 sock_lock_init_class_and_name(sk, 1278 af_family_slock_key_strings[sk->sk_family], 1279 af_family_slock_keys + sk->sk_family, 1280 af_family_key_strings[sk->sk_family], 1281 af_family_keys + sk->sk_family); 1282 } 1283 1284 /* 1285 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1286 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1287 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1288 */ 1289 static void sock_copy(struct sock *nsk, const struct sock *osk) 1290 { 1291 #ifdef CONFIG_SECURITY_NETWORK 1292 void *sptr = nsk->sk_security; 1293 #endif 1294 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1295 1296 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1297 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1298 1299 #ifdef CONFIG_SECURITY_NETWORK 1300 nsk->sk_security = sptr; 1301 security_sk_clone(osk, nsk); 1302 #endif 1303 } 1304 1305 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1306 { 1307 unsigned long nulls1, nulls2; 1308 1309 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1310 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1311 if (nulls1 > nulls2) 1312 swap(nulls1, nulls2); 1313 1314 if (nulls1 != 0) 1315 memset((char *)sk, 0, nulls1); 1316 memset((char *)sk + nulls1 + sizeof(void *), 0, 1317 nulls2 - nulls1 - sizeof(void *)); 1318 memset((char *)sk + nulls2 + sizeof(void *), 0, 1319 size - nulls2 - sizeof(void *)); 1320 } 1321 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1322 1323 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1324 int family) 1325 { 1326 struct sock *sk; 1327 struct kmem_cache *slab; 1328 1329 slab = prot->slab; 1330 if (slab != NULL) { 1331 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1332 if (!sk) 1333 return sk; 1334 if (priority & __GFP_ZERO) { 1335 if (prot->clear_sk) 1336 prot->clear_sk(sk, prot->obj_size); 1337 else 1338 sk_prot_clear_nulls(sk, prot->obj_size); 1339 } 1340 } else 1341 sk = kmalloc(prot->obj_size, priority); 1342 1343 if (sk != NULL) { 1344 kmemcheck_annotate_bitfield(sk, flags); 1345 1346 if (security_sk_alloc(sk, family, priority)) 1347 goto out_free; 1348 1349 if (!try_module_get(prot->owner)) 1350 goto out_free_sec; 1351 sk_tx_queue_clear(sk); 1352 } 1353 1354 return sk; 1355 1356 out_free_sec: 1357 security_sk_free(sk); 1358 out_free: 1359 if (slab != NULL) 1360 kmem_cache_free(slab, sk); 1361 else 1362 kfree(sk); 1363 return NULL; 1364 } 1365 1366 static void sk_prot_free(struct proto *prot, struct sock *sk) 1367 { 1368 struct kmem_cache *slab; 1369 struct module *owner; 1370 1371 owner = prot->owner; 1372 slab = prot->slab; 1373 1374 security_sk_free(sk); 1375 if (slab != NULL) 1376 kmem_cache_free(slab, sk); 1377 else 1378 kfree(sk); 1379 module_put(owner); 1380 } 1381 1382 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 1383 void sock_update_netprioidx(struct sock *sk) 1384 { 1385 if (in_interrupt()) 1386 return; 1387 1388 sk->sk_cgrp_prioidx = task_netprioidx(current); 1389 } 1390 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1391 #endif 1392 1393 /** 1394 * sk_alloc - All socket objects are allocated here 1395 * @net: the applicable net namespace 1396 * @family: protocol family 1397 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1398 * @prot: struct proto associated with this new sock instance 1399 * @kern: is this to be a kernel socket? 1400 */ 1401 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1402 struct proto *prot, int kern) 1403 { 1404 struct sock *sk; 1405 1406 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1407 if (sk) { 1408 sk->sk_family = family; 1409 /* 1410 * See comment in struct sock definition to understand 1411 * why we need sk_prot_creator -acme 1412 */ 1413 sk->sk_prot = sk->sk_prot_creator = prot; 1414 sock_lock_init(sk); 1415 sk->sk_net_refcnt = kern ? 0 : 1; 1416 if (likely(sk->sk_net_refcnt)) 1417 get_net(net); 1418 sock_net_set(sk, net); 1419 atomic_set(&sk->sk_wmem_alloc, 1); 1420 1421 sock_update_classid(sk); 1422 sock_update_netprioidx(sk); 1423 } 1424 1425 return sk; 1426 } 1427 EXPORT_SYMBOL(sk_alloc); 1428 1429 static void __sk_free(struct sock *sk) 1430 { 1431 struct sk_filter *filter; 1432 1433 if (sk->sk_destruct) 1434 sk->sk_destruct(sk); 1435 1436 filter = rcu_dereference_check(sk->sk_filter, 1437 atomic_read(&sk->sk_wmem_alloc) == 0); 1438 if (filter) { 1439 sk_filter_uncharge(sk, filter); 1440 RCU_INIT_POINTER(sk->sk_filter, NULL); 1441 } 1442 1443 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1444 1445 if (atomic_read(&sk->sk_omem_alloc)) 1446 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1447 __func__, atomic_read(&sk->sk_omem_alloc)); 1448 1449 if (sk->sk_peer_cred) 1450 put_cred(sk->sk_peer_cred); 1451 put_pid(sk->sk_peer_pid); 1452 if (likely(sk->sk_net_refcnt)) 1453 put_net(sock_net(sk)); 1454 sk_prot_free(sk->sk_prot_creator, sk); 1455 } 1456 1457 void sk_free(struct sock *sk) 1458 { 1459 /* 1460 * We subtract one from sk_wmem_alloc and can know if 1461 * some packets are still in some tx queue. 1462 * If not null, sock_wfree() will call __sk_free(sk) later 1463 */ 1464 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1465 __sk_free(sk); 1466 } 1467 EXPORT_SYMBOL(sk_free); 1468 1469 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1470 { 1471 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1472 sock_update_memcg(newsk); 1473 } 1474 1475 /** 1476 * sk_clone_lock - clone a socket, and lock its clone 1477 * @sk: the socket to clone 1478 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1479 * 1480 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1481 */ 1482 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1483 { 1484 struct sock *newsk; 1485 bool is_charged = true; 1486 1487 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1488 if (newsk != NULL) { 1489 struct sk_filter *filter; 1490 1491 sock_copy(newsk, sk); 1492 1493 /* SANITY */ 1494 get_net(sock_net(newsk)); 1495 sk_node_init(&newsk->sk_node); 1496 sock_lock_init(newsk); 1497 bh_lock_sock(newsk); 1498 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1499 newsk->sk_backlog.len = 0; 1500 1501 atomic_set(&newsk->sk_rmem_alloc, 0); 1502 /* 1503 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1504 */ 1505 atomic_set(&newsk->sk_wmem_alloc, 1); 1506 atomic_set(&newsk->sk_omem_alloc, 0); 1507 skb_queue_head_init(&newsk->sk_receive_queue); 1508 skb_queue_head_init(&newsk->sk_write_queue); 1509 1510 spin_lock_init(&newsk->sk_dst_lock); 1511 rwlock_init(&newsk->sk_callback_lock); 1512 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1513 af_callback_keys + newsk->sk_family, 1514 af_family_clock_key_strings[newsk->sk_family]); 1515 1516 newsk->sk_dst_cache = NULL; 1517 newsk->sk_wmem_queued = 0; 1518 newsk->sk_forward_alloc = 0; 1519 newsk->sk_send_head = NULL; 1520 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1521 1522 sock_reset_flag(newsk, SOCK_DONE); 1523 skb_queue_head_init(&newsk->sk_error_queue); 1524 1525 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1526 if (filter != NULL) 1527 /* though it's an empty new sock, the charging may fail 1528 * if sysctl_optmem_max was changed between creation of 1529 * original socket and cloning 1530 */ 1531 is_charged = sk_filter_charge(newsk, filter); 1532 1533 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) { 1534 /* It is still raw copy of parent, so invalidate 1535 * destructor and make plain sk_free() */ 1536 newsk->sk_destruct = NULL; 1537 bh_unlock_sock(newsk); 1538 sk_free(newsk); 1539 newsk = NULL; 1540 goto out; 1541 } 1542 1543 newsk->sk_err = 0; 1544 newsk->sk_priority = 0; 1545 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1546 atomic64_set(&newsk->sk_cookie, 0); 1547 /* 1548 * Before updating sk_refcnt, we must commit prior changes to memory 1549 * (Documentation/RCU/rculist_nulls.txt for details) 1550 */ 1551 smp_wmb(); 1552 atomic_set(&newsk->sk_refcnt, 2); 1553 1554 /* 1555 * Increment the counter in the same struct proto as the master 1556 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1557 * is the same as sk->sk_prot->socks, as this field was copied 1558 * with memcpy). 1559 * 1560 * This _changes_ the previous behaviour, where 1561 * tcp_create_openreq_child always was incrementing the 1562 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1563 * to be taken into account in all callers. -acme 1564 */ 1565 sk_refcnt_debug_inc(newsk); 1566 sk_set_socket(newsk, NULL); 1567 newsk->sk_wq = NULL; 1568 1569 sk_update_clone(sk, newsk); 1570 1571 if (newsk->sk_prot->sockets_allocated) 1572 sk_sockets_allocated_inc(newsk); 1573 1574 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1575 net_enable_timestamp(); 1576 } 1577 out: 1578 return newsk; 1579 } 1580 EXPORT_SYMBOL_GPL(sk_clone_lock); 1581 1582 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1583 { 1584 u32 max_segs = 1; 1585 1586 __sk_dst_set(sk, dst); 1587 sk->sk_route_caps = dst->dev->features; 1588 if (sk->sk_route_caps & NETIF_F_GSO) 1589 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1590 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1591 if (sk_can_gso(sk)) { 1592 if (dst->header_len) { 1593 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1594 } else { 1595 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1596 sk->sk_gso_max_size = dst->dev->gso_max_size; 1597 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 1598 } 1599 } 1600 sk->sk_gso_max_segs = max_segs; 1601 } 1602 EXPORT_SYMBOL_GPL(sk_setup_caps); 1603 1604 /* 1605 * Simple resource managers for sockets. 1606 */ 1607 1608 1609 /* 1610 * Write buffer destructor automatically called from kfree_skb. 1611 */ 1612 void sock_wfree(struct sk_buff *skb) 1613 { 1614 struct sock *sk = skb->sk; 1615 unsigned int len = skb->truesize; 1616 1617 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1618 /* 1619 * Keep a reference on sk_wmem_alloc, this will be released 1620 * after sk_write_space() call 1621 */ 1622 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1623 sk->sk_write_space(sk); 1624 len = 1; 1625 } 1626 /* 1627 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1628 * could not do because of in-flight packets 1629 */ 1630 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1631 __sk_free(sk); 1632 } 1633 EXPORT_SYMBOL(sock_wfree); 1634 1635 void skb_orphan_partial(struct sk_buff *skb) 1636 { 1637 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1638 * so we do not completely orphan skb, but transfert all 1639 * accounted bytes but one, to avoid unexpected reorders. 1640 */ 1641 if (skb->destructor == sock_wfree 1642 #ifdef CONFIG_INET 1643 || skb->destructor == tcp_wfree 1644 #endif 1645 ) { 1646 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1647 skb->truesize = 1; 1648 } else { 1649 skb_orphan(skb); 1650 } 1651 } 1652 EXPORT_SYMBOL(skb_orphan_partial); 1653 1654 /* 1655 * Read buffer destructor automatically called from kfree_skb. 1656 */ 1657 void sock_rfree(struct sk_buff *skb) 1658 { 1659 struct sock *sk = skb->sk; 1660 unsigned int len = skb->truesize; 1661 1662 atomic_sub(len, &sk->sk_rmem_alloc); 1663 sk_mem_uncharge(sk, len); 1664 } 1665 EXPORT_SYMBOL(sock_rfree); 1666 1667 /* 1668 * Buffer destructor for skbs that are not used directly in read or write 1669 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 1670 */ 1671 void sock_efree(struct sk_buff *skb) 1672 { 1673 sock_put(skb->sk); 1674 } 1675 EXPORT_SYMBOL(sock_efree); 1676 1677 kuid_t sock_i_uid(struct sock *sk) 1678 { 1679 kuid_t uid; 1680 1681 read_lock_bh(&sk->sk_callback_lock); 1682 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1683 read_unlock_bh(&sk->sk_callback_lock); 1684 return uid; 1685 } 1686 EXPORT_SYMBOL(sock_i_uid); 1687 1688 unsigned long sock_i_ino(struct sock *sk) 1689 { 1690 unsigned long ino; 1691 1692 read_lock_bh(&sk->sk_callback_lock); 1693 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1694 read_unlock_bh(&sk->sk_callback_lock); 1695 return ino; 1696 } 1697 EXPORT_SYMBOL(sock_i_ino); 1698 1699 /* 1700 * Allocate a skb from the socket's send buffer. 1701 */ 1702 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1703 gfp_t priority) 1704 { 1705 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1706 struct sk_buff *skb = alloc_skb(size, priority); 1707 if (skb) { 1708 skb_set_owner_w(skb, sk); 1709 return skb; 1710 } 1711 } 1712 return NULL; 1713 } 1714 EXPORT_SYMBOL(sock_wmalloc); 1715 1716 /* 1717 * Allocate a memory block from the socket's option memory buffer. 1718 */ 1719 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1720 { 1721 if ((unsigned int)size <= sysctl_optmem_max && 1722 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1723 void *mem; 1724 /* First do the add, to avoid the race if kmalloc 1725 * might sleep. 1726 */ 1727 atomic_add(size, &sk->sk_omem_alloc); 1728 mem = kmalloc(size, priority); 1729 if (mem) 1730 return mem; 1731 atomic_sub(size, &sk->sk_omem_alloc); 1732 } 1733 return NULL; 1734 } 1735 EXPORT_SYMBOL(sock_kmalloc); 1736 1737 /* Free an option memory block. Note, we actually want the inline 1738 * here as this allows gcc to detect the nullify and fold away the 1739 * condition entirely. 1740 */ 1741 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 1742 const bool nullify) 1743 { 1744 if (WARN_ON_ONCE(!mem)) 1745 return; 1746 if (nullify) 1747 kzfree(mem); 1748 else 1749 kfree(mem); 1750 atomic_sub(size, &sk->sk_omem_alloc); 1751 } 1752 1753 void sock_kfree_s(struct sock *sk, void *mem, int size) 1754 { 1755 __sock_kfree_s(sk, mem, size, false); 1756 } 1757 EXPORT_SYMBOL(sock_kfree_s); 1758 1759 void sock_kzfree_s(struct sock *sk, void *mem, int size) 1760 { 1761 __sock_kfree_s(sk, mem, size, true); 1762 } 1763 EXPORT_SYMBOL(sock_kzfree_s); 1764 1765 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1766 I think, these locks should be removed for datagram sockets. 1767 */ 1768 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1769 { 1770 DEFINE_WAIT(wait); 1771 1772 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1773 for (;;) { 1774 if (!timeo) 1775 break; 1776 if (signal_pending(current)) 1777 break; 1778 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1779 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1780 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1781 break; 1782 if (sk->sk_shutdown & SEND_SHUTDOWN) 1783 break; 1784 if (sk->sk_err) 1785 break; 1786 timeo = schedule_timeout(timeo); 1787 } 1788 finish_wait(sk_sleep(sk), &wait); 1789 return timeo; 1790 } 1791 1792 1793 /* 1794 * Generic send/receive buffer handlers 1795 */ 1796 1797 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1798 unsigned long data_len, int noblock, 1799 int *errcode, int max_page_order) 1800 { 1801 struct sk_buff *skb; 1802 long timeo; 1803 int err; 1804 1805 timeo = sock_sndtimeo(sk, noblock); 1806 for (;;) { 1807 err = sock_error(sk); 1808 if (err != 0) 1809 goto failure; 1810 1811 err = -EPIPE; 1812 if (sk->sk_shutdown & SEND_SHUTDOWN) 1813 goto failure; 1814 1815 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 1816 break; 1817 1818 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1819 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1820 err = -EAGAIN; 1821 if (!timeo) 1822 goto failure; 1823 if (signal_pending(current)) 1824 goto interrupted; 1825 timeo = sock_wait_for_wmem(sk, timeo); 1826 } 1827 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 1828 errcode, sk->sk_allocation); 1829 if (skb) 1830 skb_set_owner_w(skb, sk); 1831 return skb; 1832 1833 interrupted: 1834 err = sock_intr_errno(timeo); 1835 failure: 1836 *errcode = err; 1837 return NULL; 1838 } 1839 EXPORT_SYMBOL(sock_alloc_send_pskb); 1840 1841 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1842 int noblock, int *errcode) 1843 { 1844 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1845 } 1846 EXPORT_SYMBOL(sock_alloc_send_skb); 1847 1848 /* On 32bit arches, an skb frag is limited to 2^15 */ 1849 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1850 1851 /** 1852 * skb_page_frag_refill - check that a page_frag contains enough room 1853 * @sz: minimum size of the fragment we want to get 1854 * @pfrag: pointer to page_frag 1855 * @gfp: priority for memory allocation 1856 * 1857 * Note: While this allocator tries to use high order pages, there is 1858 * no guarantee that allocations succeed. Therefore, @sz MUST be 1859 * less or equal than PAGE_SIZE. 1860 */ 1861 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 1862 { 1863 if (pfrag->page) { 1864 if (atomic_read(&pfrag->page->_count) == 1) { 1865 pfrag->offset = 0; 1866 return true; 1867 } 1868 if (pfrag->offset + sz <= pfrag->size) 1869 return true; 1870 put_page(pfrag->page); 1871 } 1872 1873 pfrag->offset = 0; 1874 if (SKB_FRAG_PAGE_ORDER) { 1875 pfrag->page = alloc_pages(gfp | __GFP_COMP | 1876 __GFP_NOWARN | __GFP_NORETRY, 1877 SKB_FRAG_PAGE_ORDER); 1878 if (likely(pfrag->page)) { 1879 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 1880 return true; 1881 } 1882 } 1883 pfrag->page = alloc_page(gfp); 1884 if (likely(pfrag->page)) { 1885 pfrag->size = PAGE_SIZE; 1886 return true; 1887 } 1888 return false; 1889 } 1890 EXPORT_SYMBOL(skb_page_frag_refill); 1891 1892 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1893 { 1894 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1895 return true; 1896 1897 sk_enter_memory_pressure(sk); 1898 sk_stream_moderate_sndbuf(sk); 1899 return false; 1900 } 1901 EXPORT_SYMBOL(sk_page_frag_refill); 1902 1903 static void __lock_sock(struct sock *sk) 1904 __releases(&sk->sk_lock.slock) 1905 __acquires(&sk->sk_lock.slock) 1906 { 1907 DEFINE_WAIT(wait); 1908 1909 for (;;) { 1910 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1911 TASK_UNINTERRUPTIBLE); 1912 spin_unlock_bh(&sk->sk_lock.slock); 1913 schedule(); 1914 spin_lock_bh(&sk->sk_lock.slock); 1915 if (!sock_owned_by_user(sk)) 1916 break; 1917 } 1918 finish_wait(&sk->sk_lock.wq, &wait); 1919 } 1920 1921 static void __release_sock(struct sock *sk) 1922 __releases(&sk->sk_lock.slock) 1923 __acquires(&sk->sk_lock.slock) 1924 { 1925 struct sk_buff *skb = sk->sk_backlog.head; 1926 1927 do { 1928 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1929 bh_unlock_sock(sk); 1930 1931 do { 1932 struct sk_buff *next = skb->next; 1933 1934 prefetch(next); 1935 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1936 skb->next = NULL; 1937 sk_backlog_rcv(sk, skb); 1938 1939 /* 1940 * We are in process context here with softirqs 1941 * disabled, use cond_resched_softirq() to preempt. 1942 * This is safe to do because we've taken the backlog 1943 * queue private: 1944 */ 1945 cond_resched_softirq(); 1946 1947 skb = next; 1948 } while (skb != NULL); 1949 1950 bh_lock_sock(sk); 1951 } while ((skb = sk->sk_backlog.head) != NULL); 1952 1953 /* 1954 * Doing the zeroing here guarantee we can not loop forever 1955 * while a wild producer attempts to flood us. 1956 */ 1957 sk->sk_backlog.len = 0; 1958 } 1959 1960 /** 1961 * sk_wait_data - wait for data to arrive at sk_receive_queue 1962 * @sk: sock to wait on 1963 * @timeo: for how long 1964 * 1965 * Now socket state including sk->sk_err is changed only under lock, 1966 * hence we may omit checks after joining wait queue. 1967 * We check receive queue before schedule() only as optimization; 1968 * it is very likely that release_sock() added new data. 1969 */ 1970 int sk_wait_data(struct sock *sk, long *timeo) 1971 { 1972 int rc; 1973 DEFINE_WAIT(wait); 1974 1975 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1976 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1977 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1978 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1979 finish_wait(sk_sleep(sk), &wait); 1980 return rc; 1981 } 1982 EXPORT_SYMBOL(sk_wait_data); 1983 1984 /** 1985 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1986 * @sk: socket 1987 * @size: memory size to allocate 1988 * @kind: allocation type 1989 * 1990 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1991 * rmem allocation. This function assumes that protocols which have 1992 * memory_pressure use sk_wmem_queued as write buffer accounting. 1993 */ 1994 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1995 { 1996 struct proto *prot = sk->sk_prot; 1997 int amt = sk_mem_pages(size); 1998 long allocated; 1999 int parent_status = UNDER_LIMIT; 2000 2001 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 2002 2003 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 2004 2005 /* Under limit. */ 2006 if (parent_status == UNDER_LIMIT && 2007 allocated <= sk_prot_mem_limits(sk, 0)) { 2008 sk_leave_memory_pressure(sk); 2009 return 1; 2010 } 2011 2012 /* Under pressure. (we or our parents) */ 2013 if ((parent_status > SOFT_LIMIT) || 2014 allocated > sk_prot_mem_limits(sk, 1)) 2015 sk_enter_memory_pressure(sk); 2016 2017 /* Over hard limit (we or our parents) */ 2018 if ((parent_status == OVER_LIMIT) || 2019 (allocated > sk_prot_mem_limits(sk, 2))) 2020 goto suppress_allocation; 2021 2022 /* guarantee minimum buffer size under pressure */ 2023 if (kind == SK_MEM_RECV) { 2024 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2025 return 1; 2026 2027 } else { /* SK_MEM_SEND */ 2028 if (sk->sk_type == SOCK_STREAM) { 2029 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2030 return 1; 2031 } else if (atomic_read(&sk->sk_wmem_alloc) < 2032 prot->sysctl_wmem[0]) 2033 return 1; 2034 } 2035 2036 if (sk_has_memory_pressure(sk)) { 2037 int alloc; 2038 2039 if (!sk_under_memory_pressure(sk)) 2040 return 1; 2041 alloc = sk_sockets_allocated_read_positive(sk); 2042 if (sk_prot_mem_limits(sk, 2) > alloc * 2043 sk_mem_pages(sk->sk_wmem_queued + 2044 atomic_read(&sk->sk_rmem_alloc) + 2045 sk->sk_forward_alloc)) 2046 return 1; 2047 } 2048 2049 suppress_allocation: 2050 2051 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2052 sk_stream_moderate_sndbuf(sk); 2053 2054 /* Fail only if socket is _under_ its sndbuf. 2055 * In this case we cannot block, so that we have to fail. 2056 */ 2057 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2058 return 1; 2059 } 2060 2061 trace_sock_exceed_buf_limit(sk, prot, allocated); 2062 2063 /* Alas. Undo changes. */ 2064 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2065 2066 sk_memory_allocated_sub(sk, amt); 2067 2068 return 0; 2069 } 2070 EXPORT_SYMBOL(__sk_mem_schedule); 2071 2072 /** 2073 * __sk_reclaim - reclaim memory_allocated 2074 * @sk: socket 2075 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2076 */ 2077 void __sk_mem_reclaim(struct sock *sk, int amount) 2078 { 2079 amount >>= SK_MEM_QUANTUM_SHIFT; 2080 sk_memory_allocated_sub(sk, amount); 2081 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2082 2083 if (sk_under_memory_pressure(sk) && 2084 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2085 sk_leave_memory_pressure(sk); 2086 } 2087 EXPORT_SYMBOL(__sk_mem_reclaim); 2088 2089 2090 /* 2091 * Set of default routines for initialising struct proto_ops when 2092 * the protocol does not support a particular function. In certain 2093 * cases where it makes no sense for a protocol to have a "do nothing" 2094 * function, some default processing is provided. 2095 */ 2096 2097 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2098 { 2099 return -EOPNOTSUPP; 2100 } 2101 EXPORT_SYMBOL(sock_no_bind); 2102 2103 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2104 int len, int flags) 2105 { 2106 return -EOPNOTSUPP; 2107 } 2108 EXPORT_SYMBOL(sock_no_connect); 2109 2110 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2111 { 2112 return -EOPNOTSUPP; 2113 } 2114 EXPORT_SYMBOL(sock_no_socketpair); 2115 2116 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2117 { 2118 return -EOPNOTSUPP; 2119 } 2120 EXPORT_SYMBOL(sock_no_accept); 2121 2122 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2123 int *len, int peer) 2124 { 2125 return -EOPNOTSUPP; 2126 } 2127 EXPORT_SYMBOL(sock_no_getname); 2128 2129 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2130 { 2131 return 0; 2132 } 2133 EXPORT_SYMBOL(sock_no_poll); 2134 2135 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2136 { 2137 return -EOPNOTSUPP; 2138 } 2139 EXPORT_SYMBOL(sock_no_ioctl); 2140 2141 int sock_no_listen(struct socket *sock, int backlog) 2142 { 2143 return -EOPNOTSUPP; 2144 } 2145 EXPORT_SYMBOL(sock_no_listen); 2146 2147 int sock_no_shutdown(struct socket *sock, int how) 2148 { 2149 return -EOPNOTSUPP; 2150 } 2151 EXPORT_SYMBOL(sock_no_shutdown); 2152 2153 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2154 char __user *optval, unsigned int optlen) 2155 { 2156 return -EOPNOTSUPP; 2157 } 2158 EXPORT_SYMBOL(sock_no_setsockopt); 2159 2160 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2161 char __user *optval, int __user *optlen) 2162 { 2163 return -EOPNOTSUPP; 2164 } 2165 EXPORT_SYMBOL(sock_no_getsockopt); 2166 2167 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2168 { 2169 return -EOPNOTSUPP; 2170 } 2171 EXPORT_SYMBOL(sock_no_sendmsg); 2172 2173 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2174 int flags) 2175 { 2176 return -EOPNOTSUPP; 2177 } 2178 EXPORT_SYMBOL(sock_no_recvmsg); 2179 2180 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2181 { 2182 /* Mirror missing mmap method error code */ 2183 return -ENODEV; 2184 } 2185 EXPORT_SYMBOL(sock_no_mmap); 2186 2187 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2188 { 2189 ssize_t res; 2190 struct msghdr msg = {.msg_flags = flags}; 2191 struct kvec iov; 2192 char *kaddr = kmap(page); 2193 iov.iov_base = kaddr + offset; 2194 iov.iov_len = size; 2195 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2196 kunmap(page); 2197 return res; 2198 } 2199 EXPORT_SYMBOL(sock_no_sendpage); 2200 2201 /* 2202 * Default Socket Callbacks 2203 */ 2204 2205 static void sock_def_wakeup(struct sock *sk) 2206 { 2207 struct socket_wq *wq; 2208 2209 rcu_read_lock(); 2210 wq = rcu_dereference(sk->sk_wq); 2211 if (wq_has_sleeper(wq)) 2212 wake_up_interruptible_all(&wq->wait); 2213 rcu_read_unlock(); 2214 } 2215 2216 static void sock_def_error_report(struct sock *sk) 2217 { 2218 struct socket_wq *wq; 2219 2220 rcu_read_lock(); 2221 wq = rcu_dereference(sk->sk_wq); 2222 if (wq_has_sleeper(wq)) 2223 wake_up_interruptible_poll(&wq->wait, POLLERR); 2224 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2225 rcu_read_unlock(); 2226 } 2227 2228 static void sock_def_readable(struct sock *sk) 2229 { 2230 struct socket_wq *wq; 2231 2232 rcu_read_lock(); 2233 wq = rcu_dereference(sk->sk_wq); 2234 if (wq_has_sleeper(wq)) 2235 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2236 POLLRDNORM | POLLRDBAND); 2237 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2238 rcu_read_unlock(); 2239 } 2240 2241 static void sock_def_write_space(struct sock *sk) 2242 { 2243 struct socket_wq *wq; 2244 2245 rcu_read_lock(); 2246 2247 /* Do not wake up a writer until he can make "significant" 2248 * progress. --DaveM 2249 */ 2250 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2251 wq = rcu_dereference(sk->sk_wq); 2252 if (wq_has_sleeper(wq)) 2253 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2254 POLLWRNORM | POLLWRBAND); 2255 2256 /* Should agree with poll, otherwise some programs break */ 2257 if (sock_writeable(sk)) 2258 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2259 } 2260 2261 rcu_read_unlock(); 2262 } 2263 2264 static void sock_def_destruct(struct sock *sk) 2265 { 2266 kfree(sk->sk_protinfo); 2267 } 2268 2269 void sk_send_sigurg(struct sock *sk) 2270 { 2271 if (sk->sk_socket && sk->sk_socket->file) 2272 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2273 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2274 } 2275 EXPORT_SYMBOL(sk_send_sigurg); 2276 2277 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2278 unsigned long expires) 2279 { 2280 if (!mod_timer(timer, expires)) 2281 sock_hold(sk); 2282 } 2283 EXPORT_SYMBOL(sk_reset_timer); 2284 2285 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2286 { 2287 if (del_timer(timer)) 2288 __sock_put(sk); 2289 } 2290 EXPORT_SYMBOL(sk_stop_timer); 2291 2292 void sock_init_data(struct socket *sock, struct sock *sk) 2293 { 2294 skb_queue_head_init(&sk->sk_receive_queue); 2295 skb_queue_head_init(&sk->sk_write_queue); 2296 skb_queue_head_init(&sk->sk_error_queue); 2297 2298 sk->sk_send_head = NULL; 2299 2300 init_timer(&sk->sk_timer); 2301 2302 sk->sk_allocation = GFP_KERNEL; 2303 sk->sk_rcvbuf = sysctl_rmem_default; 2304 sk->sk_sndbuf = sysctl_wmem_default; 2305 sk->sk_state = TCP_CLOSE; 2306 sk_set_socket(sk, sock); 2307 2308 sock_set_flag(sk, SOCK_ZAPPED); 2309 2310 if (sock) { 2311 sk->sk_type = sock->type; 2312 sk->sk_wq = sock->wq; 2313 sock->sk = sk; 2314 } else 2315 sk->sk_wq = NULL; 2316 2317 spin_lock_init(&sk->sk_dst_lock); 2318 rwlock_init(&sk->sk_callback_lock); 2319 lockdep_set_class_and_name(&sk->sk_callback_lock, 2320 af_callback_keys + sk->sk_family, 2321 af_family_clock_key_strings[sk->sk_family]); 2322 2323 sk->sk_state_change = sock_def_wakeup; 2324 sk->sk_data_ready = sock_def_readable; 2325 sk->sk_write_space = sock_def_write_space; 2326 sk->sk_error_report = sock_def_error_report; 2327 sk->sk_destruct = sock_def_destruct; 2328 2329 sk->sk_frag.page = NULL; 2330 sk->sk_frag.offset = 0; 2331 sk->sk_peek_off = -1; 2332 2333 sk->sk_peer_pid = NULL; 2334 sk->sk_peer_cred = NULL; 2335 sk->sk_write_pending = 0; 2336 sk->sk_rcvlowat = 1; 2337 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2338 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2339 2340 sk->sk_stamp = ktime_set(-1L, 0); 2341 2342 #ifdef CONFIG_NET_RX_BUSY_POLL 2343 sk->sk_napi_id = 0; 2344 sk->sk_ll_usec = sysctl_net_busy_read; 2345 #endif 2346 2347 sk->sk_max_pacing_rate = ~0U; 2348 sk->sk_pacing_rate = ~0U; 2349 /* 2350 * Before updating sk_refcnt, we must commit prior changes to memory 2351 * (Documentation/RCU/rculist_nulls.txt for details) 2352 */ 2353 smp_wmb(); 2354 atomic_set(&sk->sk_refcnt, 1); 2355 atomic_set(&sk->sk_drops, 0); 2356 } 2357 EXPORT_SYMBOL(sock_init_data); 2358 2359 void lock_sock_nested(struct sock *sk, int subclass) 2360 { 2361 might_sleep(); 2362 spin_lock_bh(&sk->sk_lock.slock); 2363 if (sk->sk_lock.owned) 2364 __lock_sock(sk); 2365 sk->sk_lock.owned = 1; 2366 spin_unlock(&sk->sk_lock.slock); 2367 /* 2368 * The sk_lock has mutex_lock() semantics here: 2369 */ 2370 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2371 local_bh_enable(); 2372 } 2373 EXPORT_SYMBOL(lock_sock_nested); 2374 2375 void release_sock(struct sock *sk) 2376 { 2377 /* 2378 * The sk_lock has mutex_unlock() semantics: 2379 */ 2380 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2381 2382 spin_lock_bh(&sk->sk_lock.slock); 2383 if (sk->sk_backlog.tail) 2384 __release_sock(sk); 2385 2386 /* Warning : release_cb() might need to release sk ownership, 2387 * ie call sock_release_ownership(sk) before us. 2388 */ 2389 if (sk->sk_prot->release_cb) 2390 sk->sk_prot->release_cb(sk); 2391 2392 sock_release_ownership(sk); 2393 if (waitqueue_active(&sk->sk_lock.wq)) 2394 wake_up(&sk->sk_lock.wq); 2395 spin_unlock_bh(&sk->sk_lock.slock); 2396 } 2397 EXPORT_SYMBOL(release_sock); 2398 2399 /** 2400 * lock_sock_fast - fast version of lock_sock 2401 * @sk: socket 2402 * 2403 * This version should be used for very small section, where process wont block 2404 * return false if fast path is taken 2405 * sk_lock.slock locked, owned = 0, BH disabled 2406 * return true if slow path is taken 2407 * sk_lock.slock unlocked, owned = 1, BH enabled 2408 */ 2409 bool lock_sock_fast(struct sock *sk) 2410 { 2411 might_sleep(); 2412 spin_lock_bh(&sk->sk_lock.slock); 2413 2414 if (!sk->sk_lock.owned) 2415 /* 2416 * Note : We must disable BH 2417 */ 2418 return false; 2419 2420 __lock_sock(sk); 2421 sk->sk_lock.owned = 1; 2422 spin_unlock(&sk->sk_lock.slock); 2423 /* 2424 * The sk_lock has mutex_lock() semantics here: 2425 */ 2426 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2427 local_bh_enable(); 2428 return true; 2429 } 2430 EXPORT_SYMBOL(lock_sock_fast); 2431 2432 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2433 { 2434 struct timeval tv; 2435 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2436 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2437 tv = ktime_to_timeval(sk->sk_stamp); 2438 if (tv.tv_sec == -1) 2439 return -ENOENT; 2440 if (tv.tv_sec == 0) { 2441 sk->sk_stamp = ktime_get_real(); 2442 tv = ktime_to_timeval(sk->sk_stamp); 2443 } 2444 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2445 } 2446 EXPORT_SYMBOL(sock_get_timestamp); 2447 2448 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2449 { 2450 struct timespec ts; 2451 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2452 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2453 ts = ktime_to_timespec(sk->sk_stamp); 2454 if (ts.tv_sec == -1) 2455 return -ENOENT; 2456 if (ts.tv_sec == 0) { 2457 sk->sk_stamp = ktime_get_real(); 2458 ts = ktime_to_timespec(sk->sk_stamp); 2459 } 2460 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2461 } 2462 EXPORT_SYMBOL(sock_get_timestampns); 2463 2464 void sock_enable_timestamp(struct sock *sk, int flag) 2465 { 2466 if (!sock_flag(sk, flag)) { 2467 unsigned long previous_flags = sk->sk_flags; 2468 2469 sock_set_flag(sk, flag); 2470 /* 2471 * we just set one of the two flags which require net 2472 * time stamping, but time stamping might have been on 2473 * already because of the other one 2474 */ 2475 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2476 net_enable_timestamp(); 2477 } 2478 } 2479 2480 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2481 int level, int type) 2482 { 2483 struct sock_exterr_skb *serr; 2484 struct sk_buff *skb; 2485 int copied, err; 2486 2487 err = -EAGAIN; 2488 skb = sock_dequeue_err_skb(sk); 2489 if (skb == NULL) 2490 goto out; 2491 2492 copied = skb->len; 2493 if (copied > len) { 2494 msg->msg_flags |= MSG_TRUNC; 2495 copied = len; 2496 } 2497 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2498 if (err) 2499 goto out_free_skb; 2500 2501 sock_recv_timestamp(msg, sk, skb); 2502 2503 serr = SKB_EXT_ERR(skb); 2504 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2505 2506 msg->msg_flags |= MSG_ERRQUEUE; 2507 err = copied; 2508 2509 out_free_skb: 2510 kfree_skb(skb); 2511 out: 2512 return err; 2513 } 2514 EXPORT_SYMBOL(sock_recv_errqueue); 2515 2516 /* 2517 * Get a socket option on an socket. 2518 * 2519 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2520 * asynchronous errors should be reported by getsockopt. We assume 2521 * this means if you specify SO_ERROR (otherwise whats the point of it). 2522 */ 2523 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2524 char __user *optval, int __user *optlen) 2525 { 2526 struct sock *sk = sock->sk; 2527 2528 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2529 } 2530 EXPORT_SYMBOL(sock_common_getsockopt); 2531 2532 #ifdef CONFIG_COMPAT 2533 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2534 char __user *optval, int __user *optlen) 2535 { 2536 struct sock *sk = sock->sk; 2537 2538 if (sk->sk_prot->compat_getsockopt != NULL) 2539 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2540 optval, optlen); 2541 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2542 } 2543 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2544 #endif 2545 2546 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 2547 int flags) 2548 { 2549 struct sock *sk = sock->sk; 2550 int addr_len = 0; 2551 int err; 2552 2553 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 2554 flags & ~MSG_DONTWAIT, &addr_len); 2555 if (err >= 0) 2556 msg->msg_namelen = addr_len; 2557 return err; 2558 } 2559 EXPORT_SYMBOL(sock_common_recvmsg); 2560 2561 /* 2562 * Set socket options on an inet socket. 2563 */ 2564 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2565 char __user *optval, unsigned int optlen) 2566 { 2567 struct sock *sk = sock->sk; 2568 2569 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2570 } 2571 EXPORT_SYMBOL(sock_common_setsockopt); 2572 2573 #ifdef CONFIG_COMPAT 2574 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2575 char __user *optval, unsigned int optlen) 2576 { 2577 struct sock *sk = sock->sk; 2578 2579 if (sk->sk_prot->compat_setsockopt != NULL) 2580 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2581 optval, optlen); 2582 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2583 } 2584 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2585 #endif 2586 2587 void sk_common_release(struct sock *sk) 2588 { 2589 if (sk->sk_prot->destroy) 2590 sk->sk_prot->destroy(sk); 2591 2592 /* 2593 * Observation: when sock_common_release is called, processes have 2594 * no access to socket. But net still has. 2595 * Step one, detach it from networking: 2596 * 2597 * A. Remove from hash tables. 2598 */ 2599 2600 sk->sk_prot->unhash(sk); 2601 2602 /* 2603 * In this point socket cannot receive new packets, but it is possible 2604 * that some packets are in flight because some CPU runs receiver and 2605 * did hash table lookup before we unhashed socket. They will achieve 2606 * receive queue and will be purged by socket destructor. 2607 * 2608 * Also we still have packets pending on receive queue and probably, 2609 * our own packets waiting in device queues. sock_destroy will drain 2610 * receive queue, but transmitted packets will delay socket destruction 2611 * until the last reference will be released. 2612 */ 2613 2614 sock_orphan(sk); 2615 2616 xfrm_sk_free_policy(sk); 2617 2618 sk_refcnt_debug_release(sk); 2619 2620 if (sk->sk_frag.page) { 2621 put_page(sk->sk_frag.page); 2622 sk->sk_frag.page = NULL; 2623 } 2624 2625 sock_put(sk); 2626 } 2627 EXPORT_SYMBOL(sk_common_release); 2628 2629 #ifdef CONFIG_PROC_FS 2630 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2631 struct prot_inuse { 2632 int val[PROTO_INUSE_NR]; 2633 }; 2634 2635 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2636 2637 #ifdef CONFIG_NET_NS 2638 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2639 { 2640 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2641 } 2642 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2643 2644 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2645 { 2646 int cpu, idx = prot->inuse_idx; 2647 int res = 0; 2648 2649 for_each_possible_cpu(cpu) 2650 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2651 2652 return res >= 0 ? res : 0; 2653 } 2654 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2655 2656 static int __net_init sock_inuse_init_net(struct net *net) 2657 { 2658 net->core.inuse = alloc_percpu(struct prot_inuse); 2659 return net->core.inuse ? 0 : -ENOMEM; 2660 } 2661 2662 static void __net_exit sock_inuse_exit_net(struct net *net) 2663 { 2664 free_percpu(net->core.inuse); 2665 } 2666 2667 static struct pernet_operations net_inuse_ops = { 2668 .init = sock_inuse_init_net, 2669 .exit = sock_inuse_exit_net, 2670 }; 2671 2672 static __init int net_inuse_init(void) 2673 { 2674 if (register_pernet_subsys(&net_inuse_ops)) 2675 panic("Cannot initialize net inuse counters"); 2676 2677 return 0; 2678 } 2679 2680 core_initcall(net_inuse_init); 2681 #else 2682 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2683 2684 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2685 { 2686 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2687 } 2688 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2689 2690 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2691 { 2692 int cpu, idx = prot->inuse_idx; 2693 int res = 0; 2694 2695 for_each_possible_cpu(cpu) 2696 res += per_cpu(prot_inuse, cpu).val[idx]; 2697 2698 return res >= 0 ? res : 0; 2699 } 2700 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2701 #endif 2702 2703 static void assign_proto_idx(struct proto *prot) 2704 { 2705 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2706 2707 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2708 pr_err("PROTO_INUSE_NR exhausted\n"); 2709 return; 2710 } 2711 2712 set_bit(prot->inuse_idx, proto_inuse_idx); 2713 } 2714 2715 static void release_proto_idx(struct proto *prot) 2716 { 2717 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2718 clear_bit(prot->inuse_idx, proto_inuse_idx); 2719 } 2720 #else 2721 static inline void assign_proto_idx(struct proto *prot) 2722 { 2723 } 2724 2725 static inline void release_proto_idx(struct proto *prot) 2726 { 2727 } 2728 #endif 2729 2730 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 2731 { 2732 if (!rsk_prot) 2733 return; 2734 kfree(rsk_prot->slab_name); 2735 rsk_prot->slab_name = NULL; 2736 if (rsk_prot->slab) { 2737 kmem_cache_destroy(rsk_prot->slab); 2738 rsk_prot->slab = NULL; 2739 } 2740 } 2741 2742 static int req_prot_init(const struct proto *prot) 2743 { 2744 struct request_sock_ops *rsk_prot = prot->rsk_prot; 2745 2746 if (!rsk_prot) 2747 return 0; 2748 2749 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 2750 prot->name); 2751 if (!rsk_prot->slab_name) 2752 return -ENOMEM; 2753 2754 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 2755 rsk_prot->obj_size, 0, 2756 0, NULL); 2757 2758 if (!rsk_prot->slab) { 2759 pr_crit("%s: Can't create request sock SLAB cache!\n", 2760 prot->name); 2761 return -ENOMEM; 2762 } 2763 return 0; 2764 } 2765 2766 int proto_register(struct proto *prot, int alloc_slab) 2767 { 2768 if (alloc_slab) { 2769 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2770 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2771 NULL); 2772 2773 if (prot->slab == NULL) { 2774 pr_crit("%s: Can't create sock SLAB cache!\n", 2775 prot->name); 2776 goto out; 2777 } 2778 2779 if (req_prot_init(prot)) 2780 goto out_free_request_sock_slab; 2781 2782 if (prot->twsk_prot != NULL) { 2783 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2784 2785 if (prot->twsk_prot->twsk_slab_name == NULL) 2786 goto out_free_request_sock_slab; 2787 2788 prot->twsk_prot->twsk_slab = 2789 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2790 prot->twsk_prot->twsk_obj_size, 2791 0, 2792 prot->slab_flags, 2793 NULL); 2794 if (prot->twsk_prot->twsk_slab == NULL) 2795 goto out_free_timewait_sock_slab_name; 2796 } 2797 } 2798 2799 mutex_lock(&proto_list_mutex); 2800 list_add(&prot->node, &proto_list); 2801 assign_proto_idx(prot); 2802 mutex_unlock(&proto_list_mutex); 2803 return 0; 2804 2805 out_free_timewait_sock_slab_name: 2806 kfree(prot->twsk_prot->twsk_slab_name); 2807 out_free_request_sock_slab: 2808 req_prot_cleanup(prot->rsk_prot); 2809 2810 kmem_cache_destroy(prot->slab); 2811 prot->slab = NULL; 2812 out: 2813 return -ENOBUFS; 2814 } 2815 EXPORT_SYMBOL(proto_register); 2816 2817 void proto_unregister(struct proto *prot) 2818 { 2819 mutex_lock(&proto_list_mutex); 2820 release_proto_idx(prot); 2821 list_del(&prot->node); 2822 mutex_unlock(&proto_list_mutex); 2823 2824 if (prot->slab != NULL) { 2825 kmem_cache_destroy(prot->slab); 2826 prot->slab = NULL; 2827 } 2828 2829 req_prot_cleanup(prot->rsk_prot); 2830 2831 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2832 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2833 kfree(prot->twsk_prot->twsk_slab_name); 2834 prot->twsk_prot->twsk_slab = NULL; 2835 } 2836 } 2837 EXPORT_SYMBOL(proto_unregister); 2838 2839 #ifdef CONFIG_PROC_FS 2840 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2841 __acquires(proto_list_mutex) 2842 { 2843 mutex_lock(&proto_list_mutex); 2844 return seq_list_start_head(&proto_list, *pos); 2845 } 2846 2847 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2848 { 2849 return seq_list_next(v, &proto_list, pos); 2850 } 2851 2852 static void proto_seq_stop(struct seq_file *seq, void *v) 2853 __releases(proto_list_mutex) 2854 { 2855 mutex_unlock(&proto_list_mutex); 2856 } 2857 2858 static char proto_method_implemented(const void *method) 2859 { 2860 return method == NULL ? 'n' : 'y'; 2861 } 2862 static long sock_prot_memory_allocated(struct proto *proto) 2863 { 2864 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2865 } 2866 2867 static char *sock_prot_memory_pressure(struct proto *proto) 2868 { 2869 return proto->memory_pressure != NULL ? 2870 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2871 } 2872 2873 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2874 { 2875 2876 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2877 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2878 proto->name, 2879 proto->obj_size, 2880 sock_prot_inuse_get(seq_file_net(seq), proto), 2881 sock_prot_memory_allocated(proto), 2882 sock_prot_memory_pressure(proto), 2883 proto->max_header, 2884 proto->slab == NULL ? "no" : "yes", 2885 module_name(proto->owner), 2886 proto_method_implemented(proto->close), 2887 proto_method_implemented(proto->connect), 2888 proto_method_implemented(proto->disconnect), 2889 proto_method_implemented(proto->accept), 2890 proto_method_implemented(proto->ioctl), 2891 proto_method_implemented(proto->init), 2892 proto_method_implemented(proto->destroy), 2893 proto_method_implemented(proto->shutdown), 2894 proto_method_implemented(proto->setsockopt), 2895 proto_method_implemented(proto->getsockopt), 2896 proto_method_implemented(proto->sendmsg), 2897 proto_method_implemented(proto->recvmsg), 2898 proto_method_implemented(proto->sendpage), 2899 proto_method_implemented(proto->bind), 2900 proto_method_implemented(proto->backlog_rcv), 2901 proto_method_implemented(proto->hash), 2902 proto_method_implemented(proto->unhash), 2903 proto_method_implemented(proto->get_port), 2904 proto_method_implemented(proto->enter_memory_pressure)); 2905 } 2906 2907 static int proto_seq_show(struct seq_file *seq, void *v) 2908 { 2909 if (v == &proto_list) 2910 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2911 "protocol", 2912 "size", 2913 "sockets", 2914 "memory", 2915 "press", 2916 "maxhdr", 2917 "slab", 2918 "module", 2919 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2920 else 2921 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2922 return 0; 2923 } 2924 2925 static const struct seq_operations proto_seq_ops = { 2926 .start = proto_seq_start, 2927 .next = proto_seq_next, 2928 .stop = proto_seq_stop, 2929 .show = proto_seq_show, 2930 }; 2931 2932 static int proto_seq_open(struct inode *inode, struct file *file) 2933 { 2934 return seq_open_net(inode, file, &proto_seq_ops, 2935 sizeof(struct seq_net_private)); 2936 } 2937 2938 static const struct file_operations proto_seq_fops = { 2939 .owner = THIS_MODULE, 2940 .open = proto_seq_open, 2941 .read = seq_read, 2942 .llseek = seq_lseek, 2943 .release = seq_release_net, 2944 }; 2945 2946 static __net_init int proto_init_net(struct net *net) 2947 { 2948 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2949 return -ENOMEM; 2950 2951 return 0; 2952 } 2953 2954 static __net_exit void proto_exit_net(struct net *net) 2955 { 2956 remove_proc_entry("protocols", net->proc_net); 2957 } 2958 2959 2960 static __net_initdata struct pernet_operations proto_net_ops = { 2961 .init = proto_init_net, 2962 .exit = proto_exit_net, 2963 }; 2964 2965 static int __init proto_init(void) 2966 { 2967 return register_pernet_subsys(&proto_net_ops); 2968 } 2969 2970 subsys_initcall(proto_init); 2971 2972 #endif /* PROC_FS */ 2973