1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the AF_INET socket handler. 8 * 9 * Version: @(#)sock.h 1.0.4 05/13/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * Corey Minyard <wf-rch!minyard@relay.EU.net> 14 * Florian La Roche <flla@stud.uni-sb.de> 15 * 16 * Fixes: 17 * Alan Cox : Volatiles in skbuff pointers. See 18 * skbuff comments. May be overdone, 19 * better to prove they can be removed 20 * than the reverse. 21 * Alan Cox : Added a zapped field for tcp to note 22 * a socket is reset and must stay shut up 23 * Alan Cox : New fields for options 24 * Pauline Middelink : identd support 25 * Alan Cox : Eliminate low level recv/recvfrom 26 * David S. Miller : New socket lookup architecture. 27 * Steve Whitehouse: Default routines for sock_ops 28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made 29 * protinfo be just a void pointer, as the 30 * protocol specific parts were moved to 31 * respective headers and ipv4/v6, etc now 32 * use private slabcaches for its socks 33 * Pedro Hortas : New flags field for socket options 34 */ 35 #ifndef _SOCK_H 36 #define _SOCK_H 37 38 #include <linux/hardirq.h> 39 #include <linux/kernel.h> 40 #include <linux/list.h> 41 #include <linux/list_nulls.h> 42 #include <linux/timer.h> 43 #include <linux/cache.h> 44 #include <linux/bitops.h> 45 #include <linux/lockdep.h> 46 #include <linux/netdevice.h> 47 #include <linux/skbuff.h> /* struct sk_buff */ 48 #include <linux/mm.h> 49 #include <linux/security.h> 50 #include <linux/slab.h> 51 #include <linux/uaccess.h> 52 #include <linux/page_counter.h> 53 #include <linux/memcontrol.h> 54 #include <linux/static_key.h> 55 #include <linux/sched.h> 56 #include <linux/wait.h> 57 #include <linux/cgroup-defs.h> 58 #include <linux/rbtree.h> 59 #include <linux/filter.h> 60 #include <linux/rculist_nulls.h> 61 #include <linux/poll.h> 62 63 #include <linux/atomic.h> 64 #include <linux/refcount.h> 65 #include <net/dst.h> 66 #include <net/checksum.h> 67 #include <net/tcp_states.h> 68 #include <linux/net_tstamp.h> 69 #include <net/l3mdev.h> 70 71 /* 72 * This structure really needs to be cleaned up. 73 * Most of it is for TCP, and not used by any of 74 * the other protocols. 75 */ 76 77 /* Define this to get the SOCK_DBG debugging facility. */ 78 #define SOCK_DEBUGGING 79 #ifdef SOCK_DEBUGGING 80 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 81 printk(KERN_DEBUG msg); } while (0) 82 #else 83 /* Validate arguments and do nothing */ 84 static inline __printf(2, 3) 85 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 86 { 87 } 88 #endif 89 90 /* This is the per-socket lock. The spinlock provides a synchronization 91 * between user contexts and software interrupt processing, whereas the 92 * mini-semaphore synchronizes multiple users amongst themselves. 93 */ 94 typedef struct { 95 spinlock_t slock; 96 int owned; 97 wait_queue_head_t wq; 98 /* 99 * We express the mutex-alike socket_lock semantics 100 * to the lock validator by explicitly managing 101 * the slock as a lock variant (in addition to 102 * the slock itself): 103 */ 104 #ifdef CONFIG_DEBUG_LOCK_ALLOC 105 struct lockdep_map dep_map; 106 #endif 107 } socket_lock_t; 108 109 struct sock; 110 struct proto; 111 struct net; 112 113 typedef __u32 __bitwise __portpair; 114 typedef __u64 __bitwise __addrpair; 115 116 /** 117 * struct sock_common - minimal network layer representation of sockets 118 * @skc_daddr: Foreign IPv4 addr 119 * @skc_rcv_saddr: Bound local IPv4 addr 120 * @skc_hash: hash value used with various protocol lookup tables 121 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 122 * @skc_dport: placeholder for inet_dport/tw_dport 123 * @skc_num: placeholder for inet_num/tw_num 124 * @skc_family: network address family 125 * @skc_state: Connection state 126 * @skc_reuse: %SO_REUSEADDR setting 127 * @skc_reuseport: %SO_REUSEPORT setting 128 * @skc_bound_dev_if: bound device index if != 0 129 * @skc_bind_node: bind hash linkage for various protocol lookup tables 130 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 131 * @skc_prot: protocol handlers inside a network family 132 * @skc_net: reference to the network namespace of this socket 133 * @skc_node: main hash linkage for various protocol lookup tables 134 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 135 * @skc_tx_queue_mapping: tx queue number for this connection 136 * @skc_rx_queue_mapping: rx queue number for this connection 137 * @skc_flags: place holder for sk_flags 138 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 139 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 140 * @skc_incoming_cpu: record/match cpu processing incoming packets 141 * @skc_refcnt: reference count 142 * 143 * This is the minimal network layer representation of sockets, the header 144 * for struct sock and struct inet_timewait_sock. 145 */ 146 struct sock_common { 147 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned 148 * address on 64bit arches : cf INET_MATCH() 149 */ 150 union { 151 __addrpair skc_addrpair; 152 struct { 153 __be32 skc_daddr; 154 __be32 skc_rcv_saddr; 155 }; 156 }; 157 union { 158 unsigned int skc_hash; 159 __u16 skc_u16hashes[2]; 160 }; 161 /* skc_dport && skc_num must be grouped as well */ 162 union { 163 __portpair skc_portpair; 164 struct { 165 __be16 skc_dport; 166 __u16 skc_num; 167 }; 168 }; 169 170 unsigned short skc_family; 171 volatile unsigned char skc_state; 172 unsigned char skc_reuse:4; 173 unsigned char skc_reuseport:1; 174 unsigned char skc_ipv6only:1; 175 unsigned char skc_net_refcnt:1; 176 int skc_bound_dev_if; 177 union { 178 struct hlist_node skc_bind_node; 179 struct hlist_node skc_portaddr_node; 180 }; 181 struct proto *skc_prot; 182 possible_net_t skc_net; 183 184 #if IS_ENABLED(CONFIG_IPV6) 185 struct in6_addr skc_v6_daddr; 186 struct in6_addr skc_v6_rcv_saddr; 187 #endif 188 189 atomic64_t skc_cookie; 190 191 /* following fields are padding to force 192 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 193 * assuming IPV6 is enabled. We use this padding differently 194 * for different kind of 'sockets' 195 */ 196 union { 197 unsigned long skc_flags; 198 struct sock *skc_listener; /* request_sock */ 199 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 200 }; 201 /* 202 * fields between dontcopy_begin/dontcopy_end 203 * are not copied in sock_copy() 204 */ 205 /* private: */ 206 int skc_dontcopy_begin[0]; 207 /* public: */ 208 union { 209 struct hlist_node skc_node; 210 struct hlist_nulls_node skc_nulls_node; 211 }; 212 unsigned short skc_tx_queue_mapping; 213 #ifdef CONFIG_XPS 214 unsigned short skc_rx_queue_mapping; 215 #endif 216 union { 217 int skc_incoming_cpu; 218 u32 skc_rcv_wnd; 219 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 220 }; 221 222 refcount_t skc_refcnt; 223 /* private: */ 224 int skc_dontcopy_end[0]; 225 union { 226 u32 skc_rxhash; 227 u32 skc_window_clamp; 228 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 229 }; 230 /* public: */ 231 }; 232 233 struct bpf_sk_storage; 234 235 /** 236 * struct sock - network layer representation of sockets 237 * @__sk_common: shared layout with inet_timewait_sock 238 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 239 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 240 * @sk_lock: synchronizer 241 * @sk_kern_sock: True if sock is using kernel lock classes 242 * @sk_rcvbuf: size of receive buffer in bytes 243 * @sk_wq: sock wait queue and async head 244 * @sk_rx_dst: receive input route used by early demux 245 * @sk_dst_cache: destination cache 246 * @sk_dst_pending_confirm: need to confirm neighbour 247 * @sk_policy: flow policy 248 * @sk_receive_queue: incoming packets 249 * @sk_wmem_alloc: transmit queue bytes committed 250 * @sk_tsq_flags: TCP Small Queues flags 251 * @sk_write_queue: Packet sending queue 252 * @sk_omem_alloc: "o" is "option" or "other" 253 * @sk_wmem_queued: persistent queue size 254 * @sk_forward_alloc: space allocated forward 255 * @sk_napi_id: id of the last napi context to receive data for sk 256 * @sk_ll_usec: usecs to busypoll when there is no data 257 * @sk_allocation: allocation mode 258 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 259 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 260 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 261 * @sk_sndbuf: size of send buffer in bytes 262 * @__sk_flags_offset: empty field used to determine location of bitfield 263 * @sk_padding: unused element for alignment 264 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 265 * @sk_no_check_rx: allow zero checksum in RX packets 266 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 267 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 268 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 269 * @sk_gso_max_size: Maximum GSO segment size to build 270 * @sk_gso_max_segs: Maximum number of GSO segments 271 * @sk_pacing_shift: scaling factor for TCP Small Queues 272 * @sk_lingertime: %SO_LINGER l_linger setting 273 * @sk_backlog: always used with the per-socket spinlock held 274 * @sk_callback_lock: used with the callbacks in the end of this struct 275 * @sk_error_queue: rarely used 276 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 277 * IPV6_ADDRFORM for instance) 278 * @sk_err: last error 279 * @sk_err_soft: errors that don't cause failure but are the cause of a 280 * persistent failure not just 'timed out' 281 * @sk_drops: raw/udp drops counter 282 * @sk_ack_backlog: current listen backlog 283 * @sk_max_ack_backlog: listen backlog set in listen() 284 * @sk_uid: user id of owner 285 * @sk_priority: %SO_PRIORITY setting 286 * @sk_type: socket type (%SOCK_STREAM, etc) 287 * @sk_protocol: which protocol this socket belongs in this network family 288 * @sk_peer_pid: &struct pid for this socket's peer 289 * @sk_peer_cred: %SO_PEERCRED setting 290 * @sk_rcvlowat: %SO_RCVLOWAT setting 291 * @sk_rcvtimeo: %SO_RCVTIMEO setting 292 * @sk_sndtimeo: %SO_SNDTIMEO setting 293 * @sk_txhash: computed flow hash for use on transmit 294 * @sk_filter: socket filtering instructions 295 * @sk_timer: sock cleanup timer 296 * @sk_stamp: time stamp of last packet received 297 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 298 * @sk_tsflags: SO_TIMESTAMPING socket options 299 * @sk_tskey: counter to disambiguate concurrent tstamp requests 300 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 301 * @sk_socket: Identd and reporting IO signals 302 * @sk_user_data: RPC layer private data 303 * @sk_frag: cached page frag 304 * @sk_peek_off: current peek_offset value 305 * @sk_send_head: front of stuff to transmit 306 * @sk_security: used by security modules 307 * @sk_mark: generic packet mark 308 * @sk_cgrp_data: cgroup data for this cgroup 309 * @sk_memcg: this socket's memory cgroup association 310 * @sk_write_pending: a write to stream socket waits to start 311 * @sk_state_change: callback to indicate change in the state of the sock 312 * @sk_data_ready: callback to indicate there is data to be processed 313 * @sk_write_space: callback to indicate there is bf sending space available 314 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 315 * @sk_backlog_rcv: callback to process the backlog 316 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 317 * @sk_reuseport_cb: reuseport group container 318 * @sk_rcu: used during RCU grace period 319 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 320 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 321 * @sk_txtime_unused: unused txtime flags 322 */ 323 struct sock { 324 /* 325 * Now struct inet_timewait_sock also uses sock_common, so please just 326 * don't add nothing before this first member (__sk_common) --acme 327 */ 328 struct sock_common __sk_common; 329 #define sk_node __sk_common.skc_node 330 #define sk_nulls_node __sk_common.skc_nulls_node 331 #define sk_refcnt __sk_common.skc_refcnt 332 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 333 #ifdef CONFIG_XPS 334 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 335 #endif 336 337 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 338 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 339 #define sk_hash __sk_common.skc_hash 340 #define sk_portpair __sk_common.skc_portpair 341 #define sk_num __sk_common.skc_num 342 #define sk_dport __sk_common.skc_dport 343 #define sk_addrpair __sk_common.skc_addrpair 344 #define sk_daddr __sk_common.skc_daddr 345 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 346 #define sk_family __sk_common.skc_family 347 #define sk_state __sk_common.skc_state 348 #define sk_reuse __sk_common.skc_reuse 349 #define sk_reuseport __sk_common.skc_reuseport 350 #define sk_ipv6only __sk_common.skc_ipv6only 351 #define sk_net_refcnt __sk_common.skc_net_refcnt 352 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 353 #define sk_bind_node __sk_common.skc_bind_node 354 #define sk_prot __sk_common.skc_prot 355 #define sk_net __sk_common.skc_net 356 #define sk_v6_daddr __sk_common.skc_v6_daddr 357 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 358 #define sk_cookie __sk_common.skc_cookie 359 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 360 #define sk_flags __sk_common.skc_flags 361 #define sk_rxhash __sk_common.skc_rxhash 362 363 socket_lock_t sk_lock; 364 atomic_t sk_drops; 365 int sk_rcvlowat; 366 struct sk_buff_head sk_error_queue; 367 struct sk_buff *sk_rx_skb_cache; 368 struct sk_buff_head sk_receive_queue; 369 /* 370 * The backlog queue is special, it is always used with 371 * the per-socket spinlock held and requires low latency 372 * access. Therefore we special case it's implementation. 373 * Note : rmem_alloc is in this structure to fill a hole 374 * on 64bit arches, not because its logically part of 375 * backlog. 376 */ 377 struct { 378 atomic_t rmem_alloc; 379 int len; 380 struct sk_buff *head; 381 struct sk_buff *tail; 382 } sk_backlog; 383 #define sk_rmem_alloc sk_backlog.rmem_alloc 384 385 int sk_forward_alloc; 386 #ifdef CONFIG_NET_RX_BUSY_POLL 387 unsigned int sk_ll_usec; 388 /* ===== mostly read cache line ===== */ 389 unsigned int sk_napi_id; 390 #endif 391 int sk_rcvbuf; 392 393 struct sk_filter __rcu *sk_filter; 394 union { 395 struct socket_wq __rcu *sk_wq; 396 struct socket_wq *sk_wq_raw; 397 }; 398 #ifdef CONFIG_XFRM 399 struct xfrm_policy __rcu *sk_policy[2]; 400 #endif 401 struct dst_entry *sk_rx_dst; 402 struct dst_entry __rcu *sk_dst_cache; 403 atomic_t sk_omem_alloc; 404 int sk_sndbuf; 405 406 /* ===== cache line for TX ===== */ 407 int sk_wmem_queued; 408 refcount_t sk_wmem_alloc; 409 unsigned long sk_tsq_flags; 410 union { 411 struct sk_buff *sk_send_head; 412 struct rb_root tcp_rtx_queue; 413 }; 414 struct sk_buff *sk_tx_skb_cache; 415 struct sk_buff_head sk_write_queue; 416 __s32 sk_peek_off; 417 int sk_write_pending; 418 __u32 sk_dst_pending_confirm; 419 u32 sk_pacing_status; /* see enum sk_pacing */ 420 long sk_sndtimeo; 421 struct timer_list sk_timer; 422 __u32 sk_priority; 423 __u32 sk_mark; 424 unsigned long sk_pacing_rate; /* bytes per second */ 425 unsigned long sk_max_pacing_rate; 426 struct page_frag sk_frag; 427 netdev_features_t sk_route_caps; 428 netdev_features_t sk_route_nocaps; 429 netdev_features_t sk_route_forced_caps; 430 int sk_gso_type; 431 unsigned int sk_gso_max_size; 432 gfp_t sk_allocation; 433 __u32 sk_txhash; 434 435 /* 436 * Because of non atomicity rules, all 437 * changes are protected by socket lock. 438 */ 439 unsigned int __sk_flags_offset[0]; 440 #ifdef __BIG_ENDIAN_BITFIELD 441 #define SK_FL_PROTO_SHIFT 16 442 #define SK_FL_PROTO_MASK 0x00ff0000 443 444 #define SK_FL_TYPE_SHIFT 0 445 #define SK_FL_TYPE_MASK 0x0000ffff 446 #else 447 #define SK_FL_PROTO_SHIFT 8 448 #define SK_FL_PROTO_MASK 0x0000ff00 449 450 #define SK_FL_TYPE_SHIFT 16 451 #define SK_FL_TYPE_MASK 0xffff0000 452 #endif 453 454 unsigned int sk_padding : 1, 455 sk_kern_sock : 1, 456 sk_no_check_tx : 1, 457 sk_no_check_rx : 1, 458 sk_userlocks : 4, 459 sk_protocol : 8, 460 sk_type : 16; 461 #define SK_PROTOCOL_MAX U8_MAX 462 u16 sk_gso_max_segs; 463 u8 sk_pacing_shift; 464 unsigned long sk_lingertime; 465 struct proto *sk_prot_creator; 466 rwlock_t sk_callback_lock; 467 int sk_err, 468 sk_err_soft; 469 u32 sk_ack_backlog; 470 u32 sk_max_ack_backlog; 471 kuid_t sk_uid; 472 struct pid *sk_peer_pid; 473 const struct cred *sk_peer_cred; 474 long sk_rcvtimeo; 475 ktime_t sk_stamp; 476 #if BITS_PER_LONG==32 477 seqlock_t sk_stamp_seq; 478 #endif 479 u16 sk_tsflags; 480 u8 sk_shutdown; 481 u32 sk_tskey; 482 atomic_t sk_zckey; 483 484 u8 sk_clockid; 485 u8 sk_txtime_deadline_mode : 1, 486 sk_txtime_report_errors : 1, 487 sk_txtime_unused : 6; 488 489 struct socket *sk_socket; 490 void *sk_user_data; 491 #ifdef CONFIG_SECURITY 492 void *sk_security; 493 #endif 494 struct sock_cgroup_data sk_cgrp_data; 495 struct mem_cgroup *sk_memcg; 496 void (*sk_state_change)(struct sock *sk); 497 void (*sk_data_ready)(struct sock *sk); 498 void (*sk_write_space)(struct sock *sk); 499 void (*sk_error_report)(struct sock *sk); 500 int (*sk_backlog_rcv)(struct sock *sk, 501 struct sk_buff *skb); 502 #ifdef CONFIG_SOCK_VALIDATE_XMIT 503 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 504 struct net_device *dev, 505 struct sk_buff *skb); 506 #endif 507 void (*sk_destruct)(struct sock *sk); 508 struct sock_reuseport __rcu *sk_reuseport_cb; 509 #ifdef CONFIG_BPF_SYSCALL 510 struct bpf_sk_storage __rcu *sk_bpf_storage; 511 #endif 512 struct rcu_head sk_rcu; 513 }; 514 515 enum sk_pacing { 516 SK_PACING_NONE = 0, 517 SK_PACING_NEEDED = 1, 518 SK_PACING_FQ = 2, 519 }; 520 521 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 522 523 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk))) 524 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr) 525 526 /* 527 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 528 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 529 * on a socket means that the socket will reuse everybody else's port 530 * without looking at the other's sk_reuse value. 531 */ 532 533 #define SK_NO_REUSE 0 534 #define SK_CAN_REUSE 1 535 #define SK_FORCE_REUSE 2 536 537 int sk_set_peek_off(struct sock *sk, int val); 538 539 static inline int sk_peek_offset(struct sock *sk, int flags) 540 { 541 if (unlikely(flags & MSG_PEEK)) { 542 return READ_ONCE(sk->sk_peek_off); 543 } 544 545 return 0; 546 } 547 548 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 549 { 550 s32 off = READ_ONCE(sk->sk_peek_off); 551 552 if (unlikely(off >= 0)) { 553 off = max_t(s32, off - val, 0); 554 WRITE_ONCE(sk->sk_peek_off, off); 555 } 556 } 557 558 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 559 { 560 sk_peek_offset_bwd(sk, -val); 561 } 562 563 /* 564 * Hashed lists helper routines 565 */ 566 static inline struct sock *sk_entry(const struct hlist_node *node) 567 { 568 return hlist_entry(node, struct sock, sk_node); 569 } 570 571 static inline struct sock *__sk_head(const struct hlist_head *head) 572 { 573 return hlist_entry(head->first, struct sock, sk_node); 574 } 575 576 static inline struct sock *sk_head(const struct hlist_head *head) 577 { 578 return hlist_empty(head) ? NULL : __sk_head(head); 579 } 580 581 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 582 { 583 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 584 } 585 586 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 587 { 588 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 589 } 590 591 static inline struct sock *sk_next(const struct sock *sk) 592 { 593 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 594 } 595 596 static inline struct sock *sk_nulls_next(const struct sock *sk) 597 { 598 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 599 hlist_nulls_entry(sk->sk_nulls_node.next, 600 struct sock, sk_nulls_node) : 601 NULL; 602 } 603 604 static inline bool sk_unhashed(const struct sock *sk) 605 { 606 return hlist_unhashed(&sk->sk_node); 607 } 608 609 static inline bool sk_hashed(const struct sock *sk) 610 { 611 return !sk_unhashed(sk); 612 } 613 614 static inline void sk_node_init(struct hlist_node *node) 615 { 616 node->pprev = NULL; 617 } 618 619 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 620 { 621 node->pprev = NULL; 622 } 623 624 static inline void __sk_del_node(struct sock *sk) 625 { 626 __hlist_del(&sk->sk_node); 627 } 628 629 /* NB: equivalent to hlist_del_init_rcu */ 630 static inline bool __sk_del_node_init(struct sock *sk) 631 { 632 if (sk_hashed(sk)) { 633 __sk_del_node(sk); 634 sk_node_init(&sk->sk_node); 635 return true; 636 } 637 return false; 638 } 639 640 /* Grab socket reference count. This operation is valid only 641 when sk is ALREADY grabbed f.e. it is found in hash table 642 or a list and the lookup is made under lock preventing hash table 643 modifications. 644 */ 645 646 static __always_inline void sock_hold(struct sock *sk) 647 { 648 refcount_inc(&sk->sk_refcnt); 649 } 650 651 /* Ungrab socket in the context, which assumes that socket refcnt 652 cannot hit zero, f.e. it is true in context of any socketcall. 653 */ 654 static __always_inline void __sock_put(struct sock *sk) 655 { 656 refcount_dec(&sk->sk_refcnt); 657 } 658 659 static inline bool sk_del_node_init(struct sock *sk) 660 { 661 bool rc = __sk_del_node_init(sk); 662 663 if (rc) { 664 /* paranoid for a while -acme */ 665 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 666 __sock_put(sk); 667 } 668 return rc; 669 } 670 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 671 672 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 673 { 674 if (sk_hashed(sk)) { 675 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 676 return true; 677 } 678 return false; 679 } 680 681 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 682 { 683 bool rc = __sk_nulls_del_node_init_rcu(sk); 684 685 if (rc) { 686 /* paranoid for a while -acme */ 687 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 688 __sock_put(sk); 689 } 690 return rc; 691 } 692 693 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 694 { 695 hlist_add_head(&sk->sk_node, list); 696 } 697 698 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 699 { 700 sock_hold(sk); 701 __sk_add_node(sk, list); 702 } 703 704 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 705 { 706 sock_hold(sk); 707 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 708 sk->sk_family == AF_INET6) 709 hlist_add_tail_rcu(&sk->sk_node, list); 710 else 711 hlist_add_head_rcu(&sk->sk_node, list); 712 } 713 714 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 715 { 716 sock_hold(sk); 717 hlist_add_tail_rcu(&sk->sk_node, list); 718 } 719 720 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 721 { 722 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 723 } 724 725 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 726 { 727 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 728 } 729 730 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 731 { 732 sock_hold(sk); 733 __sk_nulls_add_node_rcu(sk, list); 734 } 735 736 static inline void __sk_del_bind_node(struct sock *sk) 737 { 738 __hlist_del(&sk->sk_bind_node); 739 } 740 741 static inline void sk_add_bind_node(struct sock *sk, 742 struct hlist_head *list) 743 { 744 hlist_add_head(&sk->sk_bind_node, list); 745 } 746 747 #define sk_for_each(__sk, list) \ 748 hlist_for_each_entry(__sk, list, sk_node) 749 #define sk_for_each_rcu(__sk, list) \ 750 hlist_for_each_entry_rcu(__sk, list, sk_node) 751 #define sk_nulls_for_each(__sk, node, list) \ 752 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 753 #define sk_nulls_for_each_rcu(__sk, node, list) \ 754 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 755 #define sk_for_each_from(__sk) \ 756 hlist_for_each_entry_from(__sk, sk_node) 757 #define sk_nulls_for_each_from(__sk, node) \ 758 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 759 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 760 #define sk_for_each_safe(__sk, tmp, list) \ 761 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 762 #define sk_for_each_bound(__sk, list) \ 763 hlist_for_each_entry(__sk, list, sk_bind_node) 764 765 /** 766 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 767 * @tpos: the type * to use as a loop cursor. 768 * @pos: the &struct hlist_node to use as a loop cursor. 769 * @head: the head for your list. 770 * @offset: offset of hlist_node within the struct. 771 * 772 */ 773 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 774 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 775 pos != NULL && \ 776 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 777 pos = rcu_dereference(hlist_next_rcu(pos))) 778 779 static inline struct user_namespace *sk_user_ns(struct sock *sk) 780 { 781 /* Careful only use this in a context where these parameters 782 * can not change and must all be valid, such as recvmsg from 783 * userspace. 784 */ 785 return sk->sk_socket->file->f_cred->user_ns; 786 } 787 788 /* Sock flags */ 789 enum sock_flags { 790 SOCK_DEAD, 791 SOCK_DONE, 792 SOCK_URGINLINE, 793 SOCK_KEEPOPEN, 794 SOCK_LINGER, 795 SOCK_DESTROY, 796 SOCK_BROADCAST, 797 SOCK_TIMESTAMP, 798 SOCK_ZAPPED, 799 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 800 SOCK_DBG, /* %SO_DEBUG setting */ 801 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 802 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 803 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 804 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 805 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 806 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 807 SOCK_FASYNC, /* fasync() active */ 808 SOCK_RXQ_OVFL, 809 SOCK_ZEROCOPY, /* buffers from userspace */ 810 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 811 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 812 * Will use last 4 bytes of packet sent from 813 * user-space instead. 814 */ 815 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 816 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 817 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 818 SOCK_TXTIME, 819 SOCK_XDP, /* XDP is attached */ 820 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 821 }; 822 823 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 824 825 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 826 { 827 nsk->sk_flags = osk->sk_flags; 828 } 829 830 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 831 { 832 __set_bit(flag, &sk->sk_flags); 833 } 834 835 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 836 { 837 __clear_bit(flag, &sk->sk_flags); 838 } 839 840 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 841 { 842 return test_bit(flag, &sk->sk_flags); 843 } 844 845 #ifdef CONFIG_NET 846 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 847 static inline int sk_memalloc_socks(void) 848 { 849 return static_branch_unlikely(&memalloc_socks_key); 850 } 851 #else 852 853 static inline int sk_memalloc_socks(void) 854 { 855 return 0; 856 } 857 858 #endif 859 860 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 861 { 862 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 863 } 864 865 static inline void sk_acceptq_removed(struct sock *sk) 866 { 867 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 868 } 869 870 static inline void sk_acceptq_added(struct sock *sk) 871 { 872 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 873 } 874 875 static inline bool sk_acceptq_is_full(const struct sock *sk) 876 { 877 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 878 } 879 880 /* 881 * Compute minimal free write space needed to queue new packets. 882 */ 883 static inline int sk_stream_min_wspace(const struct sock *sk) 884 { 885 return READ_ONCE(sk->sk_wmem_queued) >> 1; 886 } 887 888 static inline int sk_stream_wspace(const struct sock *sk) 889 { 890 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 891 } 892 893 static inline void sk_wmem_queued_add(struct sock *sk, int val) 894 { 895 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 896 } 897 898 void sk_stream_write_space(struct sock *sk); 899 900 /* OOB backlog add */ 901 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 902 { 903 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 904 skb_dst_force(skb); 905 906 if (!sk->sk_backlog.tail) 907 WRITE_ONCE(sk->sk_backlog.head, skb); 908 else 909 sk->sk_backlog.tail->next = skb; 910 911 WRITE_ONCE(sk->sk_backlog.tail, skb); 912 skb->next = NULL; 913 } 914 915 /* 916 * Take into account size of receive queue and backlog queue 917 * Do not take into account this skb truesize, 918 * to allow even a single big packet to come. 919 */ 920 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 921 { 922 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 923 924 return qsize > limit; 925 } 926 927 /* The per-socket spinlock must be held here. */ 928 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 929 unsigned int limit) 930 { 931 if (sk_rcvqueues_full(sk, limit)) 932 return -ENOBUFS; 933 934 /* 935 * If the skb was allocated from pfmemalloc reserves, only 936 * allow SOCK_MEMALLOC sockets to use it as this socket is 937 * helping free memory 938 */ 939 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 940 return -ENOMEM; 941 942 __sk_add_backlog(sk, skb); 943 sk->sk_backlog.len += skb->truesize; 944 return 0; 945 } 946 947 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 948 949 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 950 { 951 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 952 return __sk_backlog_rcv(sk, skb); 953 954 return sk->sk_backlog_rcv(sk, skb); 955 } 956 957 static inline void sk_incoming_cpu_update(struct sock *sk) 958 { 959 int cpu = raw_smp_processor_id(); 960 961 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 962 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 963 } 964 965 static inline void sock_rps_record_flow_hash(__u32 hash) 966 { 967 #ifdef CONFIG_RPS 968 struct rps_sock_flow_table *sock_flow_table; 969 970 rcu_read_lock(); 971 sock_flow_table = rcu_dereference(rps_sock_flow_table); 972 rps_record_sock_flow(sock_flow_table, hash); 973 rcu_read_unlock(); 974 #endif 975 } 976 977 static inline void sock_rps_record_flow(const struct sock *sk) 978 { 979 #ifdef CONFIG_RPS 980 if (static_branch_unlikely(&rfs_needed)) { 981 /* Reading sk->sk_rxhash might incur an expensive cache line 982 * miss. 983 * 984 * TCP_ESTABLISHED does cover almost all states where RFS 985 * might be useful, and is cheaper [1] than testing : 986 * IPv4: inet_sk(sk)->inet_daddr 987 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 988 * OR an additional socket flag 989 * [1] : sk_state and sk_prot are in the same cache line. 990 */ 991 if (sk->sk_state == TCP_ESTABLISHED) 992 sock_rps_record_flow_hash(sk->sk_rxhash); 993 } 994 #endif 995 } 996 997 static inline void sock_rps_save_rxhash(struct sock *sk, 998 const struct sk_buff *skb) 999 { 1000 #ifdef CONFIG_RPS 1001 if (unlikely(sk->sk_rxhash != skb->hash)) 1002 sk->sk_rxhash = skb->hash; 1003 #endif 1004 } 1005 1006 static inline void sock_rps_reset_rxhash(struct sock *sk) 1007 { 1008 #ifdef CONFIG_RPS 1009 sk->sk_rxhash = 0; 1010 #endif 1011 } 1012 1013 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1014 ({ int __rc; \ 1015 release_sock(__sk); \ 1016 __rc = __condition; \ 1017 if (!__rc) { \ 1018 *(__timeo) = wait_woken(__wait, \ 1019 TASK_INTERRUPTIBLE, \ 1020 *(__timeo)); \ 1021 } \ 1022 sched_annotate_sleep(); \ 1023 lock_sock(__sk); \ 1024 __rc = __condition; \ 1025 __rc; \ 1026 }) 1027 1028 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1029 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1030 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1031 int sk_stream_error(struct sock *sk, int flags, int err); 1032 void sk_stream_kill_queues(struct sock *sk); 1033 void sk_set_memalloc(struct sock *sk); 1034 void sk_clear_memalloc(struct sock *sk); 1035 1036 void __sk_flush_backlog(struct sock *sk); 1037 1038 static inline bool sk_flush_backlog(struct sock *sk) 1039 { 1040 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1041 __sk_flush_backlog(sk); 1042 return true; 1043 } 1044 return false; 1045 } 1046 1047 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1048 1049 struct request_sock_ops; 1050 struct timewait_sock_ops; 1051 struct inet_hashinfo; 1052 struct raw_hashinfo; 1053 struct smc_hashinfo; 1054 struct module; 1055 1056 /* 1057 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1058 * un-modified. Special care is taken when initializing object to zero. 1059 */ 1060 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1061 { 1062 if (offsetof(struct sock, sk_node.next) != 0) 1063 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1064 memset(&sk->sk_node.pprev, 0, 1065 size - offsetof(struct sock, sk_node.pprev)); 1066 } 1067 1068 /* Networking protocol blocks we attach to sockets. 1069 * socket layer -> transport layer interface 1070 */ 1071 struct proto { 1072 void (*close)(struct sock *sk, 1073 long timeout); 1074 int (*pre_connect)(struct sock *sk, 1075 struct sockaddr *uaddr, 1076 int addr_len); 1077 int (*connect)(struct sock *sk, 1078 struct sockaddr *uaddr, 1079 int addr_len); 1080 int (*disconnect)(struct sock *sk, int flags); 1081 1082 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1083 bool kern); 1084 1085 int (*ioctl)(struct sock *sk, int cmd, 1086 unsigned long arg); 1087 int (*init)(struct sock *sk); 1088 void (*destroy)(struct sock *sk); 1089 void (*shutdown)(struct sock *sk, int how); 1090 int (*setsockopt)(struct sock *sk, int level, 1091 int optname, char __user *optval, 1092 unsigned int optlen); 1093 int (*getsockopt)(struct sock *sk, int level, 1094 int optname, char __user *optval, 1095 int __user *option); 1096 void (*keepalive)(struct sock *sk, int valbool); 1097 #ifdef CONFIG_COMPAT 1098 int (*compat_setsockopt)(struct sock *sk, 1099 int level, 1100 int optname, char __user *optval, 1101 unsigned int optlen); 1102 int (*compat_getsockopt)(struct sock *sk, 1103 int level, 1104 int optname, char __user *optval, 1105 int __user *option); 1106 int (*compat_ioctl)(struct sock *sk, 1107 unsigned int cmd, unsigned long arg); 1108 #endif 1109 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1110 size_t len); 1111 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1112 size_t len, int noblock, int flags, 1113 int *addr_len); 1114 int (*sendpage)(struct sock *sk, struct page *page, 1115 int offset, size_t size, int flags); 1116 int (*bind)(struct sock *sk, 1117 struct sockaddr *uaddr, int addr_len); 1118 1119 int (*backlog_rcv) (struct sock *sk, 1120 struct sk_buff *skb); 1121 1122 void (*release_cb)(struct sock *sk); 1123 1124 /* Keeping track of sk's, looking them up, and port selection methods. */ 1125 int (*hash)(struct sock *sk); 1126 void (*unhash)(struct sock *sk); 1127 void (*rehash)(struct sock *sk); 1128 int (*get_port)(struct sock *sk, unsigned short snum); 1129 1130 /* Keeping track of sockets in use */ 1131 #ifdef CONFIG_PROC_FS 1132 unsigned int inuse_idx; 1133 #endif 1134 1135 bool (*stream_memory_free)(const struct sock *sk, int wake); 1136 bool (*stream_memory_read)(const struct sock *sk); 1137 /* Memory pressure */ 1138 void (*enter_memory_pressure)(struct sock *sk); 1139 void (*leave_memory_pressure)(struct sock *sk); 1140 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1141 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1142 /* 1143 * Pressure flag: try to collapse. 1144 * Technical note: it is used by multiple contexts non atomically. 1145 * All the __sk_mem_schedule() is of this nature: accounting 1146 * is strict, actions are advisory and have some latency. 1147 */ 1148 unsigned long *memory_pressure; 1149 long *sysctl_mem; 1150 1151 int *sysctl_wmem; 1152 int *sysctl_rmem; 1153 u32 sysctl_wmem_offset; 1154 u32 sysctl_rmem_offset; 1155 1156 int max_header; 1157 bool no_autobind; 1158 1159 struct kmem_cache *slab; 1160 unsigned int obj_size; 1161 slab_flags_t slab_flags; 1162 unsigned int useroffset; /* Usercopy region offset */ 1163 unsigned int usersize; /* Usercopy region size */ 1164 1165 struct percpu_counter *orphan_count; 1166 1167 struct request_sock_ops *rsk_prot; 1168 struct timewait_sock_ops *twsk_prot; 1169 1170 union { 1171 struct inet_hashinfo *hashinfo; 1172 struct udp_table *udp_table; 1173 struct raw_hashinfo *raw_hash; 1174 struct smc_hashinfo *smc_hash; 1175 } h; 1176 1177 struct module *owner; 1178 1179 char name[32]; 1180 1181 struct list_head node; 1182 #ifdef SOCK_REFCNT_DEBUG 1183 atomic_t socks; 1184 #endif 1185 int (*diag_destroy)(struct sock *sk, int err); 1186 } __randomize_layout; 1187 1188 int proto_register(struct proto *prot, int alloc_slab); 1189 void proto_unregister(struct proto *prot); 1190 int sock_load_diag_module(int family, int protocol); 1191 1192 #ifdef SOCK_REFCNT_DEBUG 1193 static inline void sk_refcnt_debug_inc(struct sock *sk) 1194 { 1195 atomic_inc(&sk->sk_prot->socks); 1196 } 1197 1198 static inline void sk_refcnt_debug_dec(struct sock *sk) 1199 { 1200 atomic_dec(&sk->sk_prot->socks); 1201 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1202 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1203 } 1204 1205 static inline void sk_refcnt_debug_release(const struct sock *sk) 1206 { 1207 if (refcount_read(&sk->sk_refcnt) != 1) 1208 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1209 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); 1210 } 1211 #else /* SOCK_REFCNT_DEBUG */ 1212 #define sk_refcnt_debug_inc(sk) do { } while (0) 1213 #define sk_refcnt_debug_dec(sk) do { } while (0) 1214 #define sk_refcnt_debug_release(sk) do { } while (0) 1215 #endif /* SOCK_REFCNT_DEBUG */ 1216 1217 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1218 { 1219 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1220 return false; 1221 1222 return sk->sk_prot->stream_memory_free ? 1223 sk->sk_prot->stream_memory_free(sk, wake) : true; 1224 } 1225 1226 static inline bool sk_stream_memory_free(const struct sock *sk) 1227 { 1228 return __sk_stream_memory_free(sk, 0); 1229 } 1230 1231 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1232 { 1233 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1234 __sk_stream_memory_free(sk, wake); 1235 } 1236 1237 static inline bool sk_stream_is_writeable(const struct sock *sk) 1238 { 1239 return __sk_stream_is_writeable(sk, 0); 1240 } 1241 1242 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1243 struct cgroup *ancestor) 1244 { 1245 #ifdef CONFIG_SOCK_CGROUP_DATA 1246 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1247 ancestor); 1248 #else 1249 return -ENOTSUPP; 1250 #endif 1251 } 1252 1253 static inline bool sk_has_memory_pressure(const struct sock *sk) 1254 { 1255 return sk->sk_prot->memory_pressure != NULL; 1256 } 1257 1258 static inline bool sk_under_memory_pressure(const struct sock *sk) 1259 { 1260 if (!sk->sk_prot->memory_pressure) 1261 return false; 1262 1263 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1264 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1265 return true; 1266 1267 return !!*sk->sk_prot->memory_pressure; 1268 } 1269 1270 static inline long 1271 sk_memory_allocated(const struct sock *sk) 1272 { 1273 return atomic_long_read(sk->sk_prot->memory_allocated); 1274 } 1275 1276 static inline long 1277 sk_memory_allocated_add(struct sock *sk, int amt) 1278 { 1279 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); 1280 } 1281 1282 static inline void 1283 sk_memory_allocated_sub(struct sock *sk, int amt) 1284 { 1285 atomic_long_sub(amt, sk->sk_prot->memory_allocated); 1286 } 1287 1288 static inline void sk_sockets_allocated_dec(struct sock *sk) 1289 { 1290 percpu_counter_dec(sk->sk_prot->sockets_allocated); 1291 } 1292 1293 static inline void sk_sockets_allocated_inc(struct sock *sk) 1294 { 1295 percpu_counter_inc(sk->sk_prot->sockets_allocated); 1296 } 1297 1298 static inline u64 1299 sk_sockets_allocated_read_positive(struct sock *sk) 1300 { 1301 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1302 } 1303 1304 static inline int 1305 proto_sockets_allocated_sum_positive(struct proto *prot) 1306 { 1307 return percpu_counter_sum_positive(prot->sockets_allocated); 1308 } 1309 1310 static inline long 1311 proto_memory_allocated(struct proto *prot) 1312 { 1313 return atomic_long_read(prot->memory_allocated); 1314 } 1315 1316 static inline bool 1317 proto_memory_pressure(struct proto *prot) 1318 { 1319 if (!prot->memory_pressure) 1320 return false; 1321 return !!*prot->memory_pressure; 1322 } 1323 1324 1325 #ifdef CONFIG_PROC_FS 1326 /* Called with local bh disabled */ 1327 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1328 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1329 int sock_inuse_get(struct net *net); 1330 #else 1331 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1332 int inc) 1333 { 1334 } 1335 #endif 1336 1337 1338 /* With per-bucket locks this operation is not-atomic, so that 1339 * this version is not worse. 1340 */ 1341 static inline int __sk_prot_rehash(struct sock *sk) 1342 { 1343 sk->sk_prot->unhash(sk); 1344 return sk->sk_prot->hash(sk); 1345 } 1346 1347 /* About 10 seconds */ 1348 #define SOCK_DESTROY_TIME (10*HZ) 1349 1350 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1351 #define PROT_SOCK 1024 1352 1353 #define SHUTDOWN_MASK 3 1354 #define RCV_SHUTDOWN 1 1355 #define SEND_SHUTDOWN 2 1356 1357 #define SOCK_SNDBUF_LOCK 1 1358 #define SOCK_RCVBUF_LOCK 2 1359 #define SOCK_BINDADDR_LOCK 4 1360 #define SOCK_BINDPORT_LOCK 8 1361 1362 struct socket_alloc { 1363 struct socket socket; 1364 struct inode vfs_inode; 1365 }; 1366 1367 static inline struct socket *SOCKET_I(struct inode *inode) 1368 { 1369 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1370 } 1371 1372 static inline struct inode *SOCK_INODE(struct socket *socket) 1373 { 1374 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1375 } 1376 1377 /* 1378 * Functions for memory accounting 1379 */ 1380 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1381 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1382 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1383 void __sk_mem_reclaim(struct sock *sk, int amount); 1384 1385 /* We used to have PAGE_SIZE here, but systems with 64KB pages 1386 * do not necessarily have 16x time more memory than 4KB ones. 1387 */ 1388 #define SK_MEM_QUANTUM 4096 1389 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1390 #define SK_MEM_SEND 0 1391 #define SK_MEM_RECV 1 1392 1393 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ 1394 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1395 { 1396 long val = sk->sk_prot->sysctl_mem[index]; 1397 1398 #if PAGE_SIZE > SK_MEM_QUANTUM 1399 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; 1400 #elif PAGE_SIZE < SK_MEM_QUANTUM 1401 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; 1402 #endif 1403 return val; 1404 } 1405 1406 static inline int sk_mem_pages(int amt) 1407 { 1408 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1409 } 1410 1411 static inline bool sk_has_account(struct sock *sk) 1412 { 1413 /* return true if protocol supports memory accounting */ 1414 return !!sk->sk_prot->memory_allocated; 1415 } 1416 1417 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1418 { 1419 if (!sk_has_account(sk)) 1420 return true; 1421 return size <= sk->sk_forward_alloc || 1422 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1423 } 1424 1425 static inline bool 1426 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1427 { 1428 if (!sk_has_account(sk)) 1429 return true; 1430 return size<= sk->sk_forward_alloc || 1431 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1432 skb_pfmemalloc(skb); 1433 } 1434 1435 static inline void sk_mem_reclaim(struct sock *sk) 1436 { 1437 if (!sk_has_account(sk)) 1438 return; 1439 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1440 __sk_mem_reclaim(sk, sk->sk_forward_alloc); 1441 } 1442 1443 static inline void sk_mem_reclaim_partial(struct sock *sk) 1444 { 1445 if (!sk_has_account(sk)) 1446 return; 1447 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1448 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); 1449 } 1450 1451 static inline void sk_mem_charge(struct sock *sk, int size) 1452 { 1453 if (!sk_has_account(sk)) 1454 return; 1455 sk->sk_forward_alloc -= size; 1456 } 1457 1458 static inline void sk_mem_uncharge(struct sock *sk, int size) 1459 { 1460 if (!sk_has_account(sk)) 1461 return; 1462 sk->sk_forward_alloc += size; 1463 1464 /* Avoid a possible overflow. 1465 * TCP send queues can make this happen, if sk_mem_reclaim() 1466 * is not called and more than 2 GBytes are released at once. 1467 * 1468 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is 1469 * no need to hold that much forward allocation anyway. 1470 */ 1471 if (unlikely(sk->sk_forward_alloc >= 1 << 21)) 1472 __sk_mem_reclaim(sk, 1 << 20); 1473 } 1474 1475 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key); 1476 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1477 { 1478 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1479 sk_wmem_queued_add(sk, -skb->truesize); 1480 sk_mem_uncharge(sk, skb->truesize); 1481 if (static_branch_unlikely(&tcp_tx_skb_cache_key) && 1482 !sk->sk_tx_skb_cache && !skb_cloned(skb)) { 1483 skb_zcopy_clear(skb, true); 1484 sk->sk_tx_skb_cache = skb; 1485 return; 1486 } 1487 __kfree_skb(skb); 1488 } 1489 1490 static inline void sock_release_ownership(struct sock *sk) 1491 { 1492 if (sk->sk_lock.owned) { 1493 sk->sk_lock.owned = 0; 1494 1495 /* The sk_lock has mutex_unlock() semantics: */ 1496 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1497 } 1498 } 1499 1500 /* 1501 * Macro so as to not evaluate some arguments when 1502 * lockdep is not enabled. 1503 * 1504 * Mark both the sk_lock and the sk_lock.slock as a 1505 * per-address-family lock class. 1506 */ 1507 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1508 do { \ 1509 sk->sk_lock.owned = 0; \ 1510 init_waitqueue_head(&sk->sk_lock.wq); \ 1511 spin_lock_init(&(sk)->sk_lock.slock); \ 1512 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1513 sizeof((sk)->sk_lock)); \ 1514 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1515 (skey), (sname)); \ 1516 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1517 } while (0) 1518 1519 #ifdef CONFIG_LOCKDEP 1520 static inline bool lockdep_sock_is_held(const struct sock *sk) 1521 { 1522 return lockdep_is_held(&sk->sk_lock) || 1523 lockdep_is_held(&sk->sk_lock.slock); 1524 } 1525 #endif 1526 1527 void lock_sock_nested(struct sock *sk, int subclass); 1528 1529 static inline void lock_sock(struct sock *sk) 1530 { 1531 lock_sock_nested(sk, 0); 1532 } 1533 1534 void __release_sock(struct sock *sk); 1535 void release_sock(struct sock *sk); 1536 1537 /* BH context may only use the following locking interface. */ 1538 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1539 #define bh_lock_sock_nested(__sk) \ 1540 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1541 SINGLE_DEPTH_NESTING) 1542 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1543 1544 bool lock_sock_fast(struct sock *sk); 1545 /** 1546 * unlock_sock_fast - complement of lock_sock_fast 1547 * @sk: socket 1548 * @slow: slow mode 1549 * 1550 * fast unlock socket for user context. 1551 * If slow mode is on, we call regular release_sock() 1552 */ 1553 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1554 { 1555 if (slow) 1556 release_sock(sk); 1557 else 1558 spin_unlock_bh(&sk->sk_lock.slock); 1559 } 1560 1561 /* Used by processes to "lock" a socket state, so that 1562 * interrupts and bottom half handlers won't change it 1563 * from under us. It essentially blocks any incoming 1564 * packets, so that we won't get any new data or any 1565 * packets that change the state of the socket. 1566 * 1567 * While locked, BH processing will add new packets to 1568 * the backlog queue. This queue is processed by the 1569 * owner of the socket lock right before it is released. 1570 * 1571 * Since ~2.3.5 it is also exclusive sleep lock serializing 1572 * accesses from user process context. 1573 */ 1574 1575 static inline void sock_owned_by_me(const struct sock *sk) 1576 { 1577 #ifdef CONFIG_LOCKDEP 1578 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1579 #endif 1580 } 1581 1582 static inline bool sock_owned_by_user(const struct sock *sk) 1583 { 1584 sock_owned_by_me(sk); 1585 return sk->sk_lock.owned; 1586 } 1587 1588 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1589 { 1590 return sk->sk_lock.owned; 1591 } 1592 1593 /* no reclassification while locks are held */ 1594 static inline bool sock_allow_reclassification(const struct sock *csk) 1595 { 1596 struct sock *sk = (struct sock *)csk; 1597 1598 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); 1599 } 1600 1601 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1602 struct proto *prot, int kern); 1603 void sk_free(struct sock *sk); 1604 void sk_destruct(struct sock *sk); 1605 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1606 void sk_free_unlock_clone(struct sock *sk); 1607 1608 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1609 gfp_t priority); 1610 void __sock_wfree(struct sk_buff *skb); 1611 void sock_wfree(struct sk_buff *skb); 1612 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1613 gfp_t priority); 1614 void skb_orphan_partial(struct sk_buff *skb); 1615 void sock_rfree(struct sk_buff *skb); 1616 void sock_efree(struct sk_buff *skb); 1617 #ifdef CONFIG_INET 1618 void sock_edemux(struct sk_buff *skb); 1619 #else 1620 #define sock_edemux sock_efree 1621 #endif 1622 1623 int sock_setsockopt(struct socket *sock, int level, int op, 1624 char __user *optval, unsigned int optlen); 1625 1626 int sock_getsockopt(struct socket *sock, int level, int op, 1627 char __user *optval, int __user *optlen); 1628 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1629 bool timeval, bool time32); 1630 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1631 int noblock, int *errcode); 1632 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1633 unsigned long data_len, int noblock, 1634 int *errcode, int max_page_order); 1635 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1636 void sock_kfree_s(struct sock *sk, void *mem, int size); 1637 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1638 void sk_send_sigurg(struct sock *sk); 1639 1640 struct sockcm_cookie { 1641 u64 transmit_time; 1642 u32 mark; 1643 u16 tsflags; 1644 }; 1645 1646 static inline void sockcm_init(struct sockcm_cookie *sockc, 1647 const struct sock *sk) 1648 { 1649 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1650 } 1651 1652 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1653 struct sockcm_cookie *sockc); 1654 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1655 struct sockcm_cookie *sockc); 1656 1657 /* 1658 * Functions to fill in entries in struct proto_ops when a protocol 1659 * does not implement a particular function. 1660 */ 1661 int sock_no_bind(struct socket *, struct sockaddr *, int); 1662 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1663 int sock_no_socketpair(struct socket *, struct socket *); 1664 int sock_no_accept(struct socket *, struct socket *, int, bool); 1665 int sock_no_getname(struct socket *, struct sockaddr *, int); 1666 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1667 int sock_no_listen(struct socket *, int); 1668 int sock_no_shutdown(struct socket *, int); 1669 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *); 1670 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int); 1671 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1672 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1673 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1674 int sock_no_mmap(struct file *file, struct socket *sock, 1675 struct vm_area_struct *vma); 1676 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1677 size_t size, int flags); 1678 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1679 int offset, size_t size, int flags); 1680 1681 /* 1682 * Functions to fill in entries in struct proto_ops when a protocol 1683 * uses the inet style. 1684 */ 1685 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1686 char __user *optval, int __user *optlen); 1687 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1688 int flags); 1689 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1690 char __user *optval, unsigned int optlen); 1691 int compat_sock_common_getsockopt(struct socket *sock, int level, 1692 int optname, char __user *optval, int __user *optlen); 1693 int compat_sock_common_setsockopt(struct socket *sock, int level, 1694 int optname, char __user *optval, unsigned int optlen); 1695 1696 void sk_common_release(struct sock *sk); 1697 1698 /* 1699 * Default socket callbacks and setup code 1700 */ 1701 1702 /* Initialise core socket variables */ 1703 void sock_init_data(struct socket *sock, struct sock *sk); 1704 1705 /* 1706 * Socket reference counting postulates. 1707 * 1708 * * Each user of socket SHOULD hold a reference count. 1709 * * Each access point to socket (an hash table bucket, reference from a list, 1710 * running timer, skb in flight MUST hold a reference count. 1711 * * When reference count hits 0, it means it will never increase back. 1712 * * When reference count hits 0, it means that no references from 1713 * outside exist to this socket and current process on current CPU 1714 * is last user and may/should destroy this socket. 1715 * * sk_free is called from any context: process, BH, IRQ. When 1716 * it is called, socket has no references from outside -> sk_free 1717 * may release descendant resources allocated by the socket, but 1718 * to the time when it is called, socket is NOT referenced by any 1719 * hash tables, lists etc. 1720 * * Packets, delivered from outside (from network or from another process) 1721 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1722 * when they sit in queue. Otherwise, packets will leak to hole, when 1723 * socket is looked up by one cpu and unhasing is made by another CPU. 1724 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1725 * (leak to backlog). Packet socket does all the processing inside 1726 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1727 * use separate SMP lock, so that they are prone too. 1728 */ 1729 1730 /* Ungrab socket and destroy it, if it was the last reference. */ 1731 static inline void sock_put(struct sock *sk) 1732 { 1733 if (refcount_dec_and_test(&sk->sk_refcnt)) 1734 sk_free(sk); 1735 } 1736 /* Generic version of sock_put(), dealing with all sockets 1737 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1738 */ 1739 void sock_gen_put(struct sock *sk); 1740 1741 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1742 unsigned int trim_cap, bool refcounted); 1743 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1744 const int nested) 1745 { 1746 return __sk_receive_skb(sk, skb, nested, 1, true); 1747 } 1748 1749 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1750 { 1751 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1752 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1753 return; 1754 sk->sk_tx_queue_mapping = tx_queue; 1755 } 1756 1757 #define NO_QUEUE_MAPPING USHRT_MAX 1758 1759 static inline void sk_tx_queue_clear(struct sock *sk) 1760 { 1761 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1762 } 1763 1764 static inline int sk_tx_queue_get(const struct sock *sk) 1765 { 1766 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 1767 return sk->sk_tx_queue_mapping; 1768 1769 return -1; 1770 } 1771 1772 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1773 { 1774 #ifdef CONFIG_XPS 1775 if (skb_rx_queue_recorded(skb)) { 1776 u16 rx_queue = skb_get_rx_queue(skb); 1777 1778 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) 1779 return; 1780 1781 sk->sk_rx_queue_mapping = rx_queue; 1782 } 1783 #endif 1784 } 1785 1786 static inline void sk_rx_queue_clear(struct sock *sk) 1787 { 1788 #ifdef CONFIG_XPS 1789 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; 1790 #endif 1791 } 1792 1793 #ifdef CONFIG_XPS 1794 static inline int sk_rx_queue_get(const struct sock *sk) 1795 { 1796 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) 1797 return sk->sk_rx_queue_mapping; 1798 1799 return -1; 1800 } 1801 #endif 1802 1803 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1804 { 1805 sk_tx_queue_clear(sk); 1806 sk->sk_socket = sock; 1807 } 1808 1809 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1810 { 1811 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1812 return &rcu_dereference_raw(sk->sk_wq)->wait; 1813 } 1814 /* Detach socket from process context. 1815 * Announce socket dead, detach it from wait queue and inode. 1816 * Note that parent inode held reference count on this struct sock, 1817 * we do not release it in this function, because protocol 1818 * probably wants some additional cleanups or even continuing 1819 * to work with this socket (TCP). 1820 */ 1821 static inline void sock_orphan(struct sock *sk) 1822 { 1823 write_lock_bh(&sk->sk_callback_lock); 1824 sock_set_flag(sk, SOCK_DEAD); 1825 sk_set_socket(sk, NULL); 1826 sk->sk_wq = NULL; 1827 write_unlock_bh(&sk->sk_callback_lock); 1828 } 1829 1830 static inline void sock_graft(struct sock *sk, struct socket *parent) 1831 { 1832 WARN_ON(parent->sk); 1833 write_lock_bh(&sk->sk_callback_lock); 1834 rcu_assign_pointer(sk->sk_wq, &parent->wq); 1835 parent->sk = sk; 1836 sk_set_socket(sk, parent); 1837 sk->sk_uid = SOCK_INODE(parent)->i_uid; 1838 security_sock_graft(sk, parent); 1839 write_unlock_bh(&sk->sk_callback_lock); 1840 } 1841 1842 kuid_t sock_i_uid(struct sock *sk); 1843 unsigned long sock_i_ino(struct sock *sk); 1844 1845 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 1846 { 1847 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 1848 } 1849 1850 static inline u32 net_tx_rndhash(void) 1851 { 1852 u32 v = prandom_u32(); 1853 1854 return v ?: 1; 1855 } 1856 1857 static inline void sk_set_txhash(struct sock *sk) 1858 { 1859 sk->sk_txhash = net_tx_rndhash(); 1860 } 1861 1862 static inline void sk_rethink_txhash(struct sock *sk) 1863 { 1864 if (sk->sk_txhash) 1865 sk_set_txhash(sk); 1866 } 1867 1868 static inline struct dst_entry * 1869 __sk_dst_get(struct sock *sk) 1870 { 1871 return rcu_dereference_check(sk->sk_dst_cache, 1872 lockdep_sock_is_held(sk)); 1873 } 1874 1875 static inline struct dst_entry * 1876 sk_dst_get(struct sock *sk) 1877 { 1878 struct dst_entry *dst; 1879 1880 rcu_read_lock(); 1881 dst = rcu_dereference(sk->sk_dst_cache); 1882 if (dst && !atomic_inc_not_zero(&dst->__refcnt)) 1883 dst = NULL; 1884 rcu_read_unlock(); 1885 return dst; 1886 } 1887 1888 static inline void dst_negative_advice(struct sock *sk) 1889 { 1890 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1891 1892 sk_rethink_txhash(sk); 1893 1894 if (dst && dst->ops->negative_advice) { 1895 ndst = dst->ops->negative_advice(dst); 1896 1897 if (ndst != dst) { 1898 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1899 sk_tx_queue_clear(sk); 1900 sk->sk_dst_pending_confirm = 0; 1901 } 1902 } 1903 } 1904 1905 static inline void 1906 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1907 { 1908 struct dst_entry *old_dst; 1909 1910 sk_tx_queue_clear(sk); 1911 sk->sk_dst_pending_confirm = 0; 1912 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 1913 lockdep_sock_is_held(sk)); 1914 rcu_assign_pointer(sk->sk_dst_cache, dst); 1915 dst_release(old_dst); 1916 } 1917 1918 static inline void 1919 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1920 { 1921 struct dst_entry *old_dst; 1922 1923 sk_tx_queue_clear(sk); 1924 sk->sk_dst_pending_confirm = 0; 1925 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 1926 dst_release(old_dst); 1927 } 1928 1929 static inline void 1930 __sk_dst_reset(struct sock *sk) 1931 { 1932 __sk_dst_set(sk, NULL); 1933 } 1934 1935 static inline void 1936 sk_dst_reset(struct sock *sk) 1937 { 1938 sk_dst_set(sk, NULL); 1939 } 1940 1941 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1942 1943 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1944 1945 static inline void sk_dst_confirm(struct sock *sk) 1946 { 1947 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 1948 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 1949 } 1950 1951 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 1952 { 1953 if (skb_get_dst_pending_confirm(skb)) { 1954 struct sock *sk = skb->sk; 1955 unsigned long now = jiffies; 1956 1957 /* avoid dirtying neighbour */ 1958 if (READ_ONCE(n->confirmed) != now) 1959 WRITE_ONCE(n->confirmed, now); 1960 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 1961 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 1962 } 1963 } 1964 1965 bool sk_mc_loop(struct sock *sk); 1966 1967 static inline bool sk_can_gso(const struct sock *sk) 1968 { 1969 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1970 } 1971 1972 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1973 1974 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1975 { 1976 sk->sk_route_nocaps |= flags; 1977 sk->sk_route_caps &= ~flags; 1978 } 1979 1980 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1981 struct iov_iter *from, char *to, 1982 int copy, int offset) 1983 { 1984 if (skb->ip_summed == CHECKSUM_NONE) { 1985 __wsum csum = 0; 1986 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 1987 return -EFAULT; 1988 skb->csum = csum_block_add(skb->csum, csum, offset); 1989 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1990 if (!copy_from_iter_full_nocache(to, copy, from)) 1991 return -EFAULT; 1992 } else if (!copy_from_iter_full(to, copy, from)) 1993 return -EFAULT; 1994 1995 return 0; 1996 } 1997 1998 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1999 struct iov_iter *from, int copy) 2000 { 2001 int err, offset = skb->len; 2002 2003 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2004 copy, offset); 2005 if (err) 2006 __skb_trim(skb, offset); 2007 2008 return err; 2009 } 2010 2011 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2012 struct sk_buff *skb, 2013 struct page *page, 2014 int off, int copy) 2015 { 2016 int err; 2017 2018 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2019 copy, skb->len); 2020 if (err) 2021 return err; 2022 2023 skb->len += copy; 2024 skb->data_len += copy; 2025 skb->truesize += copy; 2026 sk_wmem_queued_add(sk, copy); 2027 sk_mem_charge(sk, copy); 2028 return 0; 2029 } 2030 2031 /** 2032 * sk_wmem_alloc_get - returns write allocations 2033 * @sk: socket 2034 * 2035 * Returns sk_wmem_alloc minus initial offset of one 2036 */ 2037 static inline int sk_wmem_alloc_get(const struct sock *sk) 2038 { 2039 return refcount_read(&sk->sk_wmem_alloc) - 1; 2040 } 2041 2042 /** 2043 * sk_rmem_alloc_get - returns read allocations 2044 * @sk: socket 2045 * 2046 * Returns sk_rmem_alloc 2047 */ 2048 static inline int sk_rmem_alloc_get(const struct sock *sk) 2049 { 2050 return atomic_read(&sk->sk_rmem_alloc); 2051 } 2052 2053 /** 2054 * sk_has_allocations - check if allocations are outstanding 2055 * @sk: socket 2056 * 2057 * Returns true if socket has write or read allocations 2058 */ 2059 static inline bool sk_has_allocations(const struct sock *sk) 2060 { 2061 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2062 } 2063 2064 /** 2065 * skwq_has_sleeper - check if there are any waiting processes 2066 * @wq: struct socket_wq 2067 * 2068 * Returns true if socket_wq has waiting processes 2069 * 2070 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2071 * barrier call. They were added due to the race found within the tcp code. 2072 * 2073 * Consider following tcp code paths:: 2074 * 2075 * CPU1 CPU2 2076 * sys_select receive packet 2077 * ... ... 2078 * __add_wait_queue update tp->rcv_nxt 2079 * ... ... 2080 * tp->rcv_nxt check sock_def_readable 2081 * ... { 2082 * schedule rcu_read_lock(); 2083 * wq = rcu_dereference(sk->sk_wq); 2084 * if (wq && waitqueue_active(&wq->wait)) 2085 * wake_up_interruptible(&wq->wait) 2086 * ... 2087 * } 2088 * 2089 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2090 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2091 * could then endup calling schedule and sleep forever if there are no more 2092 * data on the socket. 2093 * 2094 */ 2095 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2096 { 2097 return wq && wq_has_sleeper(&wq->wait); 2098 } 2099 2100 /** 2101 * sock_poll_wait - place memory barrier behind the poll_wait call. 2102 * @filp: file 2103 * @sock: socket to wait on 2104 * @p: poll_table 2105 * 2106 * See the comments in the wq_has_sleeper function. 2107 */ 2108 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2109 poll_table *p) 2110 { 2111 if (!poll_does_not_wait(p)) { 2112 poll_wait(filp, &sock->wq.wait, p); 2113 /* We need to be sure we are in sync with the 2114 * socket flags modification. 2115 * 2116 * This memory barrier is paired in the wq_has_sleeper. 2117 */ 2118 smp_mb(); 2119 } 2120 } 2121 2122 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2123 { 2124 if (sk->sk_txhash) { 2125 skb->l4_hash = 1; 2126 skb->hash = sk->sk_txhash; 2127 } 2128 } 2129 2130 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2131 2132 /* 2133 * Queue a received datagram if it will fit. Stream and sequenced 2134 * protocols can't normally use this as they need to fit buffers in 2135 * and play with them. 2136 * 2137 * Inlined as it's very short and called for pretty much every 2138 * packet ever received. 2139 */ 2140 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2141 { 2142 skb_orphan(skb); 2143 skb->sk = sk; 2144 skb->destructor = sock_rfree; 2145 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2146 sk_mem_charge(sk, skb->truesize); 2147 } 2148 2149 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2150 unsigned long expires); 2151 2152 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2153 2154 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2155 struct sk_buff *skb, unsigned int flags, 2156 void (*destructor)(struct sock *sk, 2157 struct sk_buff *skb)); 2158 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2159 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2160 2161 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2162 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2163 2164 /* 2165 * Recover an error report and clear atomically 2166 */ 2167 2168 static inline int sock_error(struct sock *sk) 2169 { 2170 int err; 2171 if (likely(!sk->sk_err)) 2172 return 0; 2173 err = xchg(&sk->sk_err, 0); 2174 return -err; 2175 } 2176 2177 static inline unsigned long sock_wspace(struct sock *sk) 2178 { 2179 int amt = 0; 2180 2181 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2182 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2183 if (amt < 0) 2184 amt = 0; 2185 } 2186 return amt; 2187 } 2188 2189 /* Note: 2190 * We use sk->sk_wq_raw, from contexts knowing this 2191 * pointer is not NULL and cannot disappear/change. 2192 */ 2193 static inline void sk_set_bit(int nr, struct sock *sk) 2194 { 2195 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2196 !sock_flag(sk, SOCK_FASYNC)) 2197 return; 2198 2199 set_bit(nr, &sk->sk_wq_raw->flags); 2200 } 2201 2202 static inline void sk_clear_bit(int nr, struct sock *sk) 2203 { 2204 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2205 !sock_flag(sk, SOCK_FASYNC)) 2206 return; 2207 2208 clear_bit(nr, &sk->sk_wq_raw->flags); 2209 } 2210 2211 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2212 { 2213 if (sock_flag(sk, SOCK_FASYNC)) { 2214 rcu_read_lock(); 2215 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2216 rcu_read_unlock(); 2217 } 2218 } 2219 2220 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2221 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2222 * Note: for send buffers, TCP works better if we can build two skbs at 2223 * minimum. 2224 */ 2225 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2226 2227 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2228 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2229 2230 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2231 { 2232 u32 val; 2233 2234 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2235 return; 2236 2237 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2238 2239 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2240 } 2241 2242 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 2243 bool force_schedule); 2244 2245 /** 2246 * sk_page_frag - return an appropriate page_frag 2247 * @sk: socket 2248 * 2249 * Use the per task page_frag instead of the per socket one for 2250 * optimization when we know that we're in the normal context and owns 2251 * everything that's associated with %current. 2252 * 2253 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest 2254 * inside other socket operations and end up recursing into sk_page_frag() 2255 * while it's already in use. 2256 */ 2257 static inline struct page_frag *sk_page_frag(struct sock *sk) 2258 { 2259 if (gfpflags_normal_context(sk->sk_allocation)) 2260 return ¤t->task_frag; 2261 2262 return &sk->sk_frag; 2263 } 2264 2265 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2266 2267 /* 2268 * Default write policy as shown to user space via poll/select/SIGIO 2269 */ 2270 static inline bool sock_writeable(const struct sock *sk) 2271 { 2272 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2273 } 2274 2275 static inline gfp_t gfp_any(void) 2276 { 2277 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2278 } 2279 2280 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2281 { 2282 return noblock ? 0 : sk->sk_rcvtimeo; 2283 } 2284 2285 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2286 { 2287 return noblock ? 0 : sk->sk_sndtimeo; 2288 } 2289 2290 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2291 { 2292 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2293 2294 return v ?: 1; 2295 } 2296 2297 /* Alas, with timeout socket operations are not restartable. 2298 * Compare this to poll(). 2299 */ 2300 static inline int sock_intr_errno(long timeo) 2301 { 2302 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2303 } 2304 2305 struct sock_skb_cb { 2306 u32 dropcount; 2307 }; 2308 2309 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2310 * using skb->cb[] would keep using it directly and utilize its 2311 * alignement guarantee. 2312 */ 2313 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2314 sizeof(struct sock_skb_cb))) 2315 2316 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2317 SOCK_SKB_CB_OFFSET)) 2318 2319 #define sock_skb_cb_check_size(size) \ 2320 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2321 2322 static inline void 2323 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2324 { 2325 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2326 atomic_read(&sk->sk_drops) : 0; 2327 } 2328 2329 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2330 { 2331 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2332 2333 atomic_add(segs, &sk->sk_drops); 2334 } 2335 2336 static inline ktime_t sock_read_timestamp(struct sock *sk) 2337 { 2338 #if BITS_PER_LONG==32 2339 unsigned int seq; 2340 ktime_t kt; 2341 2342 do { 2343 seq = read_seqbegin(&sk->sk_stamp_seq); 2344 kt = sk->sk_stamp; 2345 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2346 2347 return kt; 2348 #else 2349 return READ_ONCE(sk->sk_stamp); 2350 #endif 2351 } 2352 2353 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2354 { 2355 #if BITS_PER_LONG==32 2356 write_seqlock(&sk->sk_stamp_seq); 2357 sk->sk_stamp = kt; 2358 write_sequnlock(&sk->sk_stamp_seq); 2359 #else 2360 WRITE_ONCE(sk->sk_stamp, kt); 2361 #endif 2362 } 2363 2364 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2365 struct sk_buff *skb); 2366 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2367 struct sk_buff *skb); 2368 2369 static inline void 2370 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2371 { 2372 ktime_t kt = skb->tstamp; 2373 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2374 2375 /* 2376 * generate control messages if 2377 * - receive time stamping in software requested 2378 * - software time stamp available and wanted 2379 * - hardware time stamps available and wanted 2380 */ 2381 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2382 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2383 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2384 (hwtstamps->hwtstamp && 2385 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2386 __sock_recv_timestamp(msg, sk, skb); 2387 else 2388 sock_write_timestamp(sk, kt); 2389 2390 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2391 __sock_recv_wifi_status(msg, sk, skb); 2392 } 2393 2394 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2395 struct sk_buff *skb); 2396 2397 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2398 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2399 struct sk_buff *skb) 2400 { 2401 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2402 (1UL << SOCK_RCVTSTAMP)) 2403 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2404 SOF_TIMESTAMPING_RAW_HARDWARE) 2405 2406 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) 2407 __sock_recv_ts_and_drops(msg, sk, skb); 2408 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2409 sock_write_timestamp(sk, skb->tstamp); 2410 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP)) 2411 sock_write_timestamp(sk, 0); 2412 } 2413 2414 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2415 2416 /** 2417 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2418 * @sk: socket sending this packet 2419 * @tsflags: timestamping flags to use 2420 * @tx_flags: completed with instructions for time stamping 2421 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2422 * 2423 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2424 */ 2425 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2426 __u8 *tx_flags, __u32 *tskey) 2427 { 2428 if (unlikely(tsflags)) { 2429 __sock_tx_timestamp(tsflags, tx_flags); 2430 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2431 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2432 *tskey = sk->sk_tskey++; 2433 } 2434 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2435 *tx_flags |= SKBTX_WIFI_STATUS; 2436 } 2437 2438 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2439 __u8 *tx_flags) 2440 { 2441 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2442 } 2443 2444 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2445 { 2446 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2447 &skb_shinfo(skb)->tskey); 2448 } 2449 2450 /** 2451 * sk_eat_skb - Release a skb if it is no longer needed 2452 * @sk: socket to eat this skb from 2453 * @skb: socket buffer to eat 2454 * 2455 * This routine must be called with interrupts disabled or with the socket 2456 * locked so that the sk_buff queue operation is ok. 2457 */ 2458 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); 2459 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2460 { 2461 __skb_unlink(skb, &sk->sk_receive_queue); 2462 if (static_branch_unlikely(&tcp_rx_skb_cache_key) && 2463 !sk->sk_rx_skb_cache) { 2464 sk->sk_rx_skb_cache = skb; 2465 skb_orphan(skb); 2466 return; 2467 } 2468 __kfree_skb(skb); 2469 } 2470 2471 static inline 2472 struct net *sock_net(const struct sock *sk) 2473 { 2474 return read_pnet(&sk->sk_net); 2475 } 2476 2477 static inline 2478 void sock_net_set(struct sock *sk, struct net *net) 2479 { 2480 write_pnet(&sk->sk_net, net); 2481 } 2482 2483 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2484 { 2485 if (skb->sk) { 2486 struct sock *sk = skb->sk; 2487 2488 skb->destructor = NULL; 2489 skb->sk = NULL; 2490 return sk; 2491 } 2492 return NULL; 2493 } 2494 2495 /* This helper checks if a socket is a full socket, 2496 * ie _not_ a timewait or request socket. 2497 */ 2498 static inline bool sk_fullsock(const struct sock *sk) 2499 { 2500 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2501 } 2502 2503 /* Checks if this SKB belongs to an HW offloaded socket 2504 * and whether any SW fallbacks are required based on dev. 2505 * Check decrypted mark in case skb_orphan() cleared socket. 2506 */ 2507 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2508 struct net_device *dev) 2509 { 2510 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2511 struct sock *sk = skb->sk; 2512 2513 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2514 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2515 #ifdef CONFIG_TLS_DEVICE 2516 } else if (unlikely(skb->decrypted)) { 2517 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2518 kfree_skb(skb); 2519 skb = NULL; 2520 #endif 2521 } 2522 #endif 2523 2524 return skb; 2525 } 2526 2527 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2528 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2529 */ 2530 static inline bool sk_listener(const struct sock *sk) 2531 { 2532 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2533 } 2534 2535 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2536 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2537 int type); 2538 2539 bool sk_ns_capable(const struct sock *sk, 2540 struct user_namespace *user_ns, int cap); 2541 bool sk_capable(const struct sock *sk, int cap); 2542 bool sk_net_capable(const struct sock *sk, int cap); 2543 2544 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2545 2546 /* Take into consideration the size of the struct sk_buff overhead in the 2547 * determination of these values, since that is non-constant across 2548 * platforms. This makes socket queueing behavior and performance 2549 * not depend upon such differences. 2550 */ 2551 #define _SK_MEM_PACKETS 256 2552 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2553 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2554 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2555 2556 extern __u32 sysctl_wmem_max; 2557 extern __u32 sysctl_rmem_max; 2558 2559 extern int sysctl_tstamp_allow_data; 2560 extern int sysctl_optmem_max; 2561 2562 extern __u32 sysctl_wmem_default; 2563 extern __u32 sysctl_rmem_default; 2564 2565 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2566 2567 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2568 { 2569 /* Does this proto have per netns sysctl_wmem ? */ 2570 if (proto->sysctl_wmem_offset) 2571 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); 2572 2573 return *proto->sysctl_wmem; 2574 } 2575 2576 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2577 { 2578 /* Does this proto have per netns sysctl_rmem ? */ 2579 if (proto->sysctl_rmem_offset) 2580 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); 2581 2582 return *proto->sysctl_rmem; 2583 } 2584 2585 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2586 * Some wifi drivers need to tweak it to get more chunks. 2587 * They can use this helper from their ndo_start_xmit() 2588 */ 2589 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2590 { 2591 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2592 return; 2593 WRITE_ONCE(sk->sk_pacing_shift, val); 2594 } 2595 2596 /* if a socket is bound to a device, check that the given device 2597 * index is either the same or that the socket is bound to an L3 2598 * master device and the given device index is also enslaved to 2599 * that L3 master 2600 */ 2601 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2602 { 2603 int mdif; 2604 2605 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) 2606 return true; 2607 2608 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2609 if (mdif && mdif == sk->sk_bound_dev_if) 2610 return true; 2611 2612 return false; 2613 } 2614 2615 #endif /* _SOCK_H */ 2616