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/rculist_nulls.h> 60 #include <linux/poll.h> 61 #include <linux/sockptr.h> 62 #include <linux/indirect_call_wrapper.h> 63 #include <linux/atomic.h> 64 #include <linux/refcount.h> 65 #include <linux/llist.h> 66 #include <net/dst.h> 67 #include <net/checksum.h> 68 #include <net/tcp_states.h> 69 #include <linux/net_tstamp.h> 70 #include <net/l3mdev.h> 71 #include <uapi/linux/socket.h> 72 73 /* 74 * This structure really needs to be cleaned up. 75 * Most of it is for TCP, and not used by any of 76 * the other protocols. 77 */ 78 79 /* Define this to get the SOCK_DBG debugging facility. */ 80 #define SOCK_DEBUGGING 81 #ifdef SOCK_DEBUGGING 82 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 83 printk(KERN_DEBUG msg); } while (0) 84 #else 85 /* Validate arguments and do nothing */ 86 static inline __printf(2, 3) 87 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 88 { 89 } 90 #endif 91 92 /* This is the per-socket lock. The spinlock provides a synchronization 93 * between user contexts and software interrupt processing, whereas the 94 * mini-semaphore synchronizes multiple users amongst themselves. 95 */ 96 typedef struct { 97 spinlock_t slock; 98 int owned; 99 wait_queue_head_t wq; 100 /* 101 * We express the mutex-alike socket_lock semantics 102 * to the lock validator by explicitly managing 103 * the slock as a lock variant (in addition to 104 * the slock itself): 105 */ 106 #ifdef CONFIG_DEBUG_LOCK_ALLOC 107 struct lockdep_map dep_map; 108 #endif 109 } socket_lock_t; 110 111 struct sock; 112 struct proto; 113 struct net; 114 115 typedef __u32 __bitwise __portpair; 116 typedef __u64 __bitwise __addrpair; 117 118 /** 119 * struct sock_common - minimal network layer representation of sockets 120 * @skc_daddr: Foreign IPv4 addr 121 * @skc_rcv_saddr: Bound local IPv4 addr 122 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr 123 * @skc_hash: hash value used with various protocol lookup tables 124 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 125 * @skc_dport: placeholder for inet_dport/tw_dport 126 * @skc_num: placeholder for inet_num/tw_num 127 * @skc_portpair: __u32 union of @skc_dport & @skc_num 128 * @skc_family: network address family 129 * @skc_state: Connection state 130 * @skc_reuse: %SO_REUSEADDR setting 131 * @skc_reuseport: %SO_REUSEPORT setting 132 * @skc_ipv6only: socket is IPV6 only 133 * @skc_net_refcnt: socket is using net ref counting 134 * @skc_bound_dev_if: bound device index if != 0 135 * @skc_bind_node: bind hash linkage for various protocol lookup tables 136 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 137 * @skc_prot: protocol handlers inside a network family 138 * @skc_net: reference to the network namespace of this socket 139 * @skc_v6_daddr: IPV6 destination address 140 * @skc_v6_rcv_saddr: IPV6 source address 141 * @skc_cookie: socket's cookie value 142 * @skc_node: main hash linkage for various protocol lookup tables 143 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 144 * @skc_tx_queue_mapping: tx queue number for this connection 145 * @skc_rx_queue_mapping: rx queue number for this connection 146 * @skc_flags: place holder for sk_flags 147 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 148 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 149 * @skc_listener: connection request listener socket (aka rsk_listener) 150 * [union with @skc_flags] 151 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row 152 * [union with @skc_flags] 153 * @skc_incoming_cpu: record/match cpu processing incoming packets 154 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) 155 * [union with @skc_incoming_cpu] 156 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number 157 * [union with @skc_incoming_cpu] 158 * @skc_refcnt: reference count 159 * 160 * This is the minimal network layer representation of sockets, the header 161 * for struct sock and struct inet_timewait_sock. 162 */ 163 struct sock_common { 164 union { 165 __addrpair skc_addrpair; 166 struct { 167 __be32 skc_daddr; 168 __be32 skc_rcv_saddr; 169 }; 170 }; 171 union { 172 unsigned int skc_hash; 173 __u16 skc_u16hashes[2]; 174 }; 175 /* skc_dport && skc_num must be grouped as well */ 176 union { 177 __portpair skc_portpair; 178 struct { 179 __be16 skc_dport; 180 __u16 skc_num; 181 }; 182 }; 183 184 unsigned short skc_family; 185 volatile unsigned char skc_state; 186 unsigned char skc_reuse:4; 187 unsigned char skc_reuseport:1; 188 unsigned char skc_ipv6only:1; 189 unsigned char skc_net_refcnt:1; 190 int skc_bound_dev_if; 191 union { 192 struct hlist_node skc_bind_node; 193 struct hlist_node skc_portaddr_node; 194 }; 195 struct proto *skc_prot; 196 possible_net_t skc_net; 197 198 #if IS_ENABLED(CONFIG_IPV6) 199 struct in6_addr skc_v6_daddr; 200 struct in6_addr skc_v6_rcv_saddr; 201 #endif 202 203 atomic64_t skc_cookie; 204 205 /* following fields are padding to force 206 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 207 * assuming IPV6 is enabled. We use this padding differently 208 * for different kind of 'sockets' 209 */ 210 union { 211 unsigned long skc_flags; 212 struct sock *skc_listener; /* request_sock */ 213 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 214 }; 215 /* 216 * fields between dontcopy_begin/dontcopy_end 217 * are not copied in sock_copy() 218 */ 219 /* private: */ 220 int skc_dontcopy_begin[0]; 221 /* public: */ 222 union { 223 struct hlist_node skc_node; 224 struct hlist_nulls_node skc_nulls_node; 225 }; 226 unsigned short skc_tx_queue_mapping; 227 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 228 unsigned short skc_rx_queue_mapping; 229 #endif 230 union { 231 int skc_incoming_cpu; 232 u32 skc_rcv_wnd; 233 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 234 }; 235 236 refcount_t skc_refcnt; 237 /* private: */ 238 int skc_dontcopy_end[0]; 239 union { 240 u32 skc_rxhash; 241 u32 skc_window_clamp; 242 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 243 }; 244 /* public: */ 245 }; 246 247 struct bpf_local_storage; 248 struct sk_filter; 249 250 /** 251 * struct sock - network layer representation of sockets 252 * @__sk_common: shared layout with inet_timewait_sock 253 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 254 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 255 * @sk_lock: synchronizer 256 * @sk_kern_sock: True if sock is using kernel lock classes 257 * @sk_rcvbuf: size of receive buffer in bytes 258 * @sk_wq: sock wait queue and async head 259 * @sk_rx_dst: receive input route used by early demux 260 * @sk_rx_dst_ifindex: ifindex for @sk_rx_dst 261 * @sk_rx_dst_cookie: cookie for @sk_rx_dst 262 * @sk_dst_cache: destination cache 263 * @sk_dst_pending_confirm: need to confirm neighbour 264 * @sk_policy: flow policy 265 * @sk_receive_queue: incoming packets 266 * @sk_wmem_alloc: transmit queue bytes committed 267 * @sk_tsq_flags: TCP Small Queues flags 268 * @sk_write_queue: Packet sending queue 269 * @sk_omem_alloc: "o" is "option" or "other" 270 * @sk_wmem_queued: persistent queue size 271 * @sk_forward_alloc: space allocated forward 272 * @sk_reserved_mem: space reserved and non-reclaimable for the socket 273 * @sk_napi_id: id of the last napi context to receive data for sk 274 * @sk_ll_usec: usecs to busypoll when there is no data 275 * @sk_allocation: allocation mode 276 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 277 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 278 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 279 * @sk_sndbuf: size of send buffer in bytes 280 * @__sk_flags_offset: empty field used to determine location of bitfield 281 * @sk_padding: unused element for alignment 282 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 283 * @sk_no_check_rx: allow zero checksum in RX packets 284 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 285 * @sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden. 286 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 287 * @sk_gso_max_size: Maximum GSO segment size to build 288 * @sk_gso_max_segs: Maximum number of GSO segments 289 * @sk_pacing_shift: scaling factor for TCP Small Queues 290 * @sk_lingertime: %SO_LINGER l_linger setting 291 * @sk_backlog: always used with the per-socket spinlock held 292 * @sk_callback_lock: used with the callbacks in the end of this struct 293 * @sk_error_queue: rarely used 294 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 295 * IPV6_ADDRFORM for instance) 296 * @sk_err: last error 297 * @sk_err_soft: errors that don't cause failure but are the cause of a 298 * persistent failure not just 'timed out' 299 * @sk_drops: raw/udp drops counter 300 * @sk_ack_backlog: current listen backlog 301 * @sk_max_ack_backlog: listen backlog set in listen() 302 * @sk_uid: user id of owner 303 * @sk_prefer_busy_poll: prefer busypolling over softirq processing 304 * @sk_busy_poll_budget: napi processing budget when busypolling 305 * @sk_priority: %SO_PRIORITY setting 306 * @sk_type: socket type (%SOCK_STREAM, etc) 307 * @sk_protocol: which protocol this socket belongs in this network family 308 * @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred 309 * @sk_peer_pid: &struct pid for this socket's peer 310 * @sk_peer_cred: %SO_PEERCRED setting 311 * @sk_rcvlowat: %SO_RCVLOWAT setting 312 * @sk_rcvtimeo: %SO_RCVTIMEO setting 313 * @sk_sndtimeo: %SO_SNDTIMEO setting 314 * @sk_txhash: computed flow hash for use on transmit 315 * @sk_txrehash: enable TX hash rethink 316 * @sk_filter: socket filtering instructions 317 * @sk_timer: sock cleanup timer 318 * @sk_stamp: time stamp of last packet received 319 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 320 * @sk_tsflags: SO_TIMESTAMPING flags 321 * @sk_use_task_frag: allow sk_page_frag() to use current->task_frag. 322 * Sockets that can be used under memory reclaim should 323 * set this to false. 324 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock 325 * for timestamping 326 * @sk_tskey: counter to disambiguate concurrent tstamp requests 327 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 328 * @sk_socket: Identd and reporting IO signals 329 * @sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock. 330 * @sk_frag: cached page frag 331 * @sk_peek_off: current peek_offset value 332 * @sk_send_head: front of stuff to transmit 333 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] 334 * @sk_security: used by security modules 335 * @sk_mark: generic packet mark 336 * @sk_cgrp_data: cgroup data for this cgroup 337 * @sk_memcg: this socket's memory cgroup association 338 * @sk_write_pending: a write to stream socket waits to start 339 * @sk_state_change: callback to indicate change in the state of the sock 340 * @sk_data_ready: callback to indicate there is data to be processed 341 * @sk_write_space: callback to indicate there is bf sending space available 342 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 343 * @sk_backlog_rcv: callback to process the backlog 344 * @sk_validate_xmit_skb: ptr to an optional validate function 345 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 346 * @sk_reuseport_cb: reuseport group container 347 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage 348 * @sk_rcu: used during RCU grace period 349 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 350 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 351 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME 352 * @sk_txtime_unused: unused txtime flags 353 * @ns_tracker: tracker for netns reference 354 * @sk_bind2_node: bind node in the bhash2 table 355 */ 356 struct sock { 357 /* 358 * Now struct inet_timewait_sock also uses sock_common, so please just 359 * don't add nothing before this first member (__sk_common) --acme 360 */ 361 struct sock_common __sk_common; 362 #define sk_node __sk_common.skc_node 363 #define sk_nulls_node __sk_common.skc_nulls_node 364 #define sk_refcnt __sk_common.skc_refcnt 365 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 366 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 367 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 368 #endif 369 370 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 371 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 372 #define sk_hash __sk_common.skc_hash 373 #define sk_portpair __sk_common.skc_portpair 374 #define sk_num __sk_common.skc_num 375 #define sk_dport __sk_common.skc_dport 376 #define sk_addrpair __sk_common.skc_addrpair 377 #define sk_daddr __sk_common.skc_daddr 378 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 379 #define sk_family __sk_common.skc_family 380 #define sk_state __sk_common.skc_state 381 #define sk_reuse __sk_common.skc_reuse 382 #define sk_reuseport __sk_common.skc_reuseport 383 #define sk_ipv6only __sk_common.skc_ipv6only 384 #define sk_net_refcnt __sk_common.skc_net_refcnt 385 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 386 #define sk_bind_node __sk_common.skc_bind_node 387 #define sk_prot __sk_common.skc_prot 388 #define sk_net __sk_common.skc_net 389 #define sk_v6_daddr __sk_common.skc_v6_daddr 390 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 391 #define sk_cookie __sk_common.skc_cookie 392 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 393 #define sk_flags __sk_common.skc_flags 394 #define sk_rxhash __sk_common.skc_rxhash 395 396 /* early demux fields */ 397 struct dst_entry __rcu *sk_rx_dst; 398 int sk_rx_dst_ifindex; 399 u32 sk_rx_dst_cookie; 400 401 socket_lock_t sk_lock; 402 atomic_t sk_drops; 403 int sk_rcvlowat; 404 struct sk_buff_head sk_error_queue; 405 struct sk_buff_head sk_receive_queue; 406 /* 407 * The backlog queue is special, it is always used with 408 * the per-socket spinlock held and requires low latency 409 * access. Therefore we special case it's implementation. 410 * Note : rmem_alloc is in this structure to fill a hole 411 * on 64bit arches, not because its logically part of 412 * backlog. 413 */ 414 struct { 415 atomic_t rmem_alloc; 416 int len; 417 struct sk_buff *head; 418 struct sk_buff *tail; 419 } sk_backlog; 420 421 #define sk_rmem_alloc sk_backlog.rmem_alloc 422 423 int sk_forward_alloc; 424 u32 sk_reserved_mem; 425 #ifdef CONFIG_NET_RX_BUSY_POLL 426 unsigned int sk_ll_usec; 427 /* ===== mostly read cache line ===== */ 428 unsigned int sk_napi_id; 429 #endif 430 int sk_rcvbuf; 431 432 struct sk_filter __rcu *sk_filter; 433 union { 434 struct socket_wq __rcu *sk_wq; 435 /* private: */ 436 struct socket_wq *sk_wq_raw; 437 /* public: */ 438 }; 439 #ifdef CONFIG_XFRM 440 struct xfrm_policy __rcu *sk_policy[2]; 441 #endif 442 443 struct dst_entry __rcu *sk_dst_cache; 444 atomic_t sk_omem_alloc; 445 int sk_sndbuf; 446 447 /* ===== cache line for TX ===== */ 448 int sk_wmem_queued; 449 refcount_t sk_wmem_alloc; 450 unsigned long sk_tsq_flags; 451 union { 452 struct sk_buff *sk_send_head; 453 struct rb_root tcp_rtx_queue; 454 }; 455 struct sk_buff_head sk_write_queue; 456 __s32 sk_peek_off; 457 int sk_write_pending; 458 __u32 sk_dst_pending_confirm; 459 u32 sk_pacing_status; /* see enum sk_pacing */ 460 long sk_sndtimeo; 461 struct timer_list sk_timer; 462 __u32 sk_priority; 463 __u32 sk_mark; 464 unsigned long sk_pacing_rate; /* bytes per second */ 465 unsigned long sk_max_pacing_rate; 466 struct page_frag sk_frag; 467 netdev_features_t sk_route_caps; 468 int sk_gso_type; 469 unsigned int sk_gso_max_size; 470 gfp_t sk_allocation; 471 __u32 sk_txhash; 472 473 /* 474 * Because of non atomicity rules, all 475 * changes are protected by socket lock. 476 */ 477 u8 sk_gso_disabled : 1, 478 sk_kern_sock : 1, 479 sk_no_check_tx : 1, 480 sk_no_check_rx : 1, 481 sk_userlocks : 4; 482 u8 sk_pacing_shift; 483 u16 sk_type; 484 u16 sk_protocol; 485 u16 sk_gso_max_segs; 486 unsigned long sk_lingertime; 487 struct proto *sk_prot_creator; 488 rwlock_t sk_callback_lock; 489 int sk_err, 490 sk_err_soft; 491 u32 sk_ack_backlog; 492 u32 sk_max_ack_backlog; 493 kuid_t sk_uid; 494 u8 sk_txrehash; 495 #ifdef CONFIG_NET_RX_BUSY_POLL 496 u8 sk_prefer_busy_poll; 497 u16 sk_busy_poll_budget; 498 #endif 499 spinlock_t sk_peer_lock; 500 int sk_bind_phc; 501 struct pid *sk_peer_pid; 502 const struct cred *sk_peer_cred; 503 504 long sk_rcvtimeo; 505 ktime_t sk_stamp; 506 #if BITS_PER_LONG==32 507 seqlock_t sk_stamp_seq; 508 #endif 509 atomic_t sk_tskey; 510 atomic_t sk_zckey; 511 u32 sk_tsflags; 512 u8 sk_shutdown; 513 514 u8 sk_clockid; 515 u8 sk_txtime_deadline_mode : 1, 516 sk_txtime_report_errors : 1, 517 sk_txtime_unused : 6; 518 bool sk_use_task_frag; 519 520 struct socket *sk_socket; 521 void *sk_user_data; 522 #ifdef CONFIG_SECURITY 523 void *sk_security; 524 #endif 525 struct sock_cgroup_data sk_cgrp_data; 526 struct mem_cgroup *sk_memcg; 527 void (*sk_state_change)(struct sock *sk); 528 void (*sk_data_ready)(struct sock *sk); 529 void (*sk_write_space)(struct sock *sk); 530 void (*sk_error_report)(struct sock *sk); 531 int (*sk_backlog_rcv)(struct sock *sk, 532 struct sk_buff *skb); 533 #ifdef CONFIG_SOCK_VALIDATE_XMIT 534 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 535 struct net_device *dev, 536 struct sk_buff *skb); 537 #endif 538 void (*sk_destruct)(struct sock *sk); 539 struct sock_reuseport __rcu *sk_reuseport_cb; 540 #ifdef CONFIG_BPF_SYSCALL 541 struct bpf_local_storage __rcu *sk_bpf_storage; 542 #endif 543 struct rcu_head sk_rcu; 544 netns_tracker ns_tracker; 545 struct hlist_node sk_bind2_node; 546 }; 547 548 enum sk_pacing { 549 SK_PACING_NONE = 0, 550 SK_PACING_NEEDED = 1, 551 SK_PACING_FQ = 2, 552 }; 553 554 /* flag bits in sk_user_data 555 * 556 * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might 557 * not be suitable for copying when cloning the socket. For instance, 558 * it can point to a reference counted object. sk_user_data bottom 559 * bit is set if pointer must not be copied. 560 * 561 * - SK_USER_DATA_BPF: Mark whether sk_user_data field is 562 * managed/owned by a BPF reuseport array. This bit should be set 563 * when sk_user_data's sk is added to the bpf's reuseport_array. 564 * 565 * - SK_USER_DATA_PSOCK: Mark whether pointer stored in 566 * sk_user_data points to psock type. This bit should be set 567 * when sk_user_data is assigned to a psock object. 568 */ 569 #define SK_USER_DATA_NOCOPY 1UL 570 #define SK_USER_DATA_BPF 2UL 571 #define SK_USER_DATA_PSOCK 4UL 572 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\ 573 SK_USER_DATA_PSOCK) 574 575 /** 576 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied 577 * @sk: socket 578 */ 579 static inline bool sk_user_data_is_nocopy(const struct sock *sk) 580 { 581 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); 582 } 583 584 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 585 586 /** 587 * __locked_read_sk_user_data_with_flags - return the pointer 588 * only if argument flags all has been set in sk_user_data. Otherwise 589 * return NULL 590 * 591 * @sk: socket 592 * @flags: flag bits 593 * 594 * The caller must be holding sk->sk_callback_lock. 595 */ 596 static inline void * 597 __locked_read_sk_user_data_with_flags(const struct sock *sk, 598 uintptr_t flags) 599 { 600 uintptr_t sk_user_data = 601 (uintptr_t)rcu_dereference_check(__sk_user_data(sk), 602 lockdep_is_held(&sk->sk_callback_lock)); 603 604 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 605 606 if ((sk_user_data & flags) == flags) 607 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 608 return NULL; 609 } 610 611 /** 612 * __rcu_dereference_sk_user_data_with_flags - return the pointer 613 * only if argument flags all has been set in sk_user_data. Otherwise 614 * return NULL 615 * 616 * @sk: socket 617 * @flags: flag bits 618 */ 619 static inline void * 620 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk, 621 uintptr_t flags) 622 { 623 uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk)); 624 625 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 626 627 if ((sk_user_data & flags) == flags) 628 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 629 return NULL; 630 } 631 632 #define rcu_dereference_sk_user_data(sk) \ 633 __rcu_dereference_sk_user_data_with_flags(sk, 0) 634 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \ 635 ({ \ 636 uintptr_t __tmp1 = (uintptr_t)(ptr), \ 637 __tmp2 = (uintptr_t)(flags); \ 638 WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \ 639 WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \ 640 rcu_assign_pointer(__sk_user_data((sk)), \ 641 __tmp1 | __tmp2); \ 642 }) 643 #define rcu_assign_sk_user_data(sk, ptr) \ 644 __rcu_assign_sk_user_data_with_flags(sk, ptr, 0) 645 646 static inline 647 struct net *sock_net(const struct sock *sk) 648 { 649 return read_pnet(&sk->sk_net); 650 } 651 652 static inline 653 void sock_net_set(struct sock *sk, struct net *net) 654 { 655 write_pnet(&sk->sk_net, net); 656 } 657 658 /* 659 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 660 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 661 * on a socket means that the socket will reuse everybody else's port 662 * without looking at the other's sk_reuse value. 663 */ 664 665 #define SK_NO_REUSE 0 666 #define SK_CAN_REUSE 1 667 #define SK_FORCE_REUSE 2 668 669 int sk_set_peek_off(struct sock *sk, int val); 670 671 static inline int sk_peek_offset(const struct sock *sk, int flags) 672 { 673 if (unlikely(flags & MSG_PEEK)) { 674 return READ_ONCE(sk->sk_peek_off); 675 } 676 677 return 0; 678 } 679 680 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 681 { 682 s32 off = READ_ONCE(sk->sk_peek_off); 683 684 if (unlikely(off >= 0)) { 685 off = max_t(s32, off - val, 0); 686 WRITE_ONCE(sk->sk_peek_off, off); 687 } 688 } 689 690 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 691 { 692 sk_peek_offset_bwd(sk, -val); 693 } 694 695 /* 696 * Hashed lists helper routines 697 */ 698 static inline struct sock *sk_entry(const struct hlist_node *node) 699 { 700 return hlist_entry(node, struct sock, sk_node); 701 } 702 703 static inline struct sock *__sk_head(const struct hlist_head *head) 704 { 705 return hlist_entry(head->first, struct sock, sk_node); 706 } 707 708 static inline struct sock *sk_head(const struct hlist_head *head) 709 { 710 return hlist_empty(head) ? NULL : __sk_head(head); 711 } 712 713 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 714 { 715 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 716 } 717 718 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 719 { 720 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 721 } 722 723 static inline struct sock *sk_next(const struct sock *sk) 724 { 725 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 726 } 727 728 static inline struct sock *sk_nulls_next(const struct sock *sk) 729 { 730 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 731 hlist_nulls_entry(sk->sk_nulls_node.next, 732 struct sock, sk_nulls_node) : 733 NULL; 734 } 735 736 static inline bool sk_unhashed(const struct sock *sk) 737 { 738 return hlist_unhashed(&sk->sk_node); 739 } 740 741 static inline bool sk_hashed(const struct sock *sk) 742 { 743 return !sk_unhashed(sk); 744 } 745 746 static inline void sk_node_init(struct hlist_node *node) 747 { 748 node->pprev = NULL; 749 } 750 751 static inline void __sk_del_node(struct sock *sk) 752 { 753 __hlist_del(&sk->sk_node); 754 } 755 756 /* NB: equivalent to hlist_del_init_rcu */ 757 static inline bool __sk_del_node_init(struct sock *sk) 758 { 759 if (sk_hashed(sk)) { 760 __sk_del_node(sk); 761 sk_node_init(&sk->sk_node); 762 return true; 763 } 764 return false; 765 } 766 767 /* Grab socket reference count. This operation is valid only 768 when sk is ALREADY grabbed f.e. it is found in hash table 769 or a list and the lookup is made under lock preventing hash table 770 modifications. 771 */ 772 773 static __always_inline void sock_hold(struct sock *sk) 774 { 775 refcount_inc(&sk->sk_refcnt); 776 } 777 778 /* Ungrab socket in the context, which assumes that socket refcnt 779 cannot hit zero, f.e. it is true in context of any socketcall. 780 */ 781 static __always_inline void __sock_put(struct sock *sk) 782 { 783 refcount_dec(&sk->sk_refcnt); 784 } 785 786 static inline bool sk_del_node_init(struct sock *sk) 787 { 788 bool rc = __sk_del_node_init(sk); 789 790 if (rc) { 791 /* paranoid for a while -acme */ 792 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 793 __sock_put(sk); 794 } 795 return rc; 796 } 797 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 798 799 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 800 { 801 if (sk_hashed(sk)) { 802 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 803 return true; 804 } 805 return false; 806 } 807 808 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 809 { 810 bool rc = __sk_nulls_del_node_init_rcu(sk); 811 812 if (rc) { 813 /* paranoid for a while -acme */ 814 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 815 __sock_put(sk); 816 } 817 return rc; 818 } 819 820 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 821 { 822 hlist_add_head(&sk->sk_node, list); 823 } 824 825 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 826 { 827 sock_hold(sk); 828 __sk_add_node(sk, list); 829 } 830 831 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 832 { 833 sock_hold(sk); 834 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 835 sk->sk_family == AF_INET6) 836 hlist_add_tail_rcu(&sk->sk_node, list); 837 else 838 hlist_add_head_rcu(&sk->sk_node, list); 839 } 840 841 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 842 { 843 sock_hold(sk); 844 hlist_add_tail_rcu(&sk->sk_node, list); 845 } 846 847 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 848 { 849 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 850 } 851 852 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 853 { 854 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 855 } 856 857 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 858 { 859 sock_hold(sk); 860 __sk_nulls_add_node_rcu(sk, list); 861 } 862 863 static inline void __sk_del_bind_node(struct sock *sk) 864 { 865 __hlist_del(&sk->sk_bind_node); 866 } 867 868 static inline void sk_add_bind_node(struct sock *sk, 869 struct hlist_head *list) 870 { 871 hlist_add_head(&sk->sk_bind_node, list); 872 } 873 874 static inline void __sk_del_bind2_node(struct sock *sk) 875 { 876 __hlist_del(&sk->sk_bind2_node); 877 } 878 879 static inline void sk_add_bind2_node(struct sock *sk, struct hlist_head *list) 880 { 881 hlist_add_head(&sk->sk_bind2_node, list); 882 } 883 884 #define sk_for_each(__sk, list) \ 885 hlist_for_each_entry(__sk, list, sk_node) 886 #define sk_for_each_rcu(__sk, list) \ 887 hlist_for_each_entry_rcu(__sk, list, sk_node) 888 #define sk_nulls_for_each(__sk, node, list) \ 889 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 890 #define sk_nulls_for_each_rcu(__sk, node, list) \ 891 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 892 #define sk_for_each_from(__sk) \ 893 hlist_for_each_entry_from(__sk, sk_node) 894 #define sk_nulls_for_each_from(__sk, node) \ 895 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 896 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 897 #define sk_for_each_safe(__sk, tmp, list) \ 898 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 899 #define sk_for_each_bound(__sk, list) \ 900 hlist_for_each_entry(__sk, list, sk_bind_node) 901 #define sk_for_each_bound_bhash2(__sk, list) \ 902 hlist_for_each_entry(__sk, list, sk_bind2_node) 903 904 /** 905 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 906 * @tpos: the type * to use as a loop cursor. 907 * @pos: the &struct hlist_node to use as a loop cursor. 908 * @head: the head for your list. 909 * @offset: offset of hlist_node within the struct. 910 * 911 */ 912 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 913 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 914 pos != NULL && \ 915 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 916 pos = rcu_dereference(hlist_next_rcu(pos))) 917 918 static inline struct user_namespace *sk_user_ns(const struct sock *sk) 919 { 920 /* Careful only use this in a context where these parameters 921 * can not change and must all be valid, such as recvmsg from 922 * userspace. 923 */ 924 return sk->sk_socket->file->f_cred->user_ns; 925 } 926 927 /* Sock flags */ 928 enum sock_flags { 929 SOCK_DEAD, 930 SOCK_DONE, 931 SOCK_URGINLINE, 932 SOCK_KEEPOPEN, 933 SOCK_LINGER, 934 SOCK_DESTROY, 935 SOCK_BROADCAST, 936 SOCK_TIMESTAMP, 937 SOCK_ZAPPED, 938 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 939 SOCK_DBG, /* %SO_DEBUG setting */ 940 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 941 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 942 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 943 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 944 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 945 SOCK_FASYNC, /* fasync() active */ 946 SOCK_RXQ_OVFL, 947 SOCK_ZEROCOPY, /* buffers from userspace */ 948 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 949 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 950 * Will use last 4 bytes of packet sent from 951 * user-space instead. 952 */ 953 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 954 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 955 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 956 SOCK_TXTIME, 957 SOCK_XDP, /* XDP is attached */ 958 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 959 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */ 960 }; 961 962 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 963 964 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk) 965 { 966 nsk->sk_flags = osk->sk_flags; 967 } 968 969 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 970 { 971 __set_bit(flag, &sk->sk_flags); 972 } 973 974 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 975 { 976 __clear_bit(flag, &sk->sk_flags); 977 } 978 979 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 980 int valbool) 981 { 982 if (valbool) 983 sock_set_flag(sk, bit); 984 else 985 sock_reset_flag(sk, bit); 986 } 987 988 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 989 { 990 return test_bit(flag, &sk->sk_flags); 991 } 992 993 #ifdef CONFIG_NET 994 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 995 static inline int sk_memalloc_socks(void) 996 { 997 return static_branch_unlikely(&memalloc_socks_key); 998 } 999 1000 void __receive_sock(struct file *file); 1001 #else 1002 1003 static inline int sk_memalloc_socks(void) 1004 { 1005 return 0; 1006 } 1007 1008 static inline void __receive_sock(struct file *file) 1009 { } 1010 #endif 1011 1012 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 1013 { 1014 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 1015 } 1016 1017 static inline void sk_acceptq_removed(struct sock *sk) 1018 { 1019 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 1020 } 1021 1022 static inline void sk_acceptq_added(struct sock *sk) 1023 { 1024 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 1025 } 1026 1027 /* Note: If you think the test should be: 1028 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 1029 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 1030 */ 1031 static inline bool sk_acceptq_is_full(const struct sock *sk) 1032 { 1033 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 1034 } 1035 1036 /* 1037 * Compute minimal free write space needed to queue new packets. 1038 */ 1039 static inline int sk_stream_min_wspace(const struct sock *sk) 1040 { 1041 return READ_ONCE(sk->sk_wmem_queued) >> 1; 1042 } 1043 1044 static inline int sk_stream_wspace(const struct sock *sk) 1045 { 1046 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 1047 } 1048 1049 static inline void sk_wmem_queued_add(struct sock *sk, int val) 1050 { 1051 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 1052 } 1053 1054 void sk_stream_write_space(struct sock *sk); 1055 1056 /* OOB backlog add */ 1057 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 1058 { 1059 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 1060 skb_dst_force(skb); 1061 1062 if (!sk->sk_backlog.tail) 1063 WRITE_ONCE(sk->sk_backlog.head, skb); 1064 else 1065 sk->sk_backlog.tail->next = skb; 1066 1067 WRITE_ONCE(sk->sk_backlog.tail, skb); 1068 skb->next = NULL; 1069 } 1070 1071 /* 1072 * Take into account size of receive queue and backlog queue 1073 * Do not take into account this skb truesize, 1074 * to allow even a single big packet to come. 1075 */ 1076 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 1077 { 1078 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 1079 1080 return qsize > limit; 1081 } 1082 1083 /* The per-socket spinlock must be held here. */ 1084 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 1085 unsigned int limit) 1086 { 1087 if (sk_rcvqueues_full(sk, limit)) 1088 return -ENOBUFS; 1089 1090 /* 1091 * If the skb was allocated from pfmemalloc reserves, only 1092 * allow SOCK_MEMALLOC sockets to use it as this socket is 1093 * helping free memory 1094 */ 1095 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1096 return -ENOMEM; 1097 1098 __sk_add_backlog(sk, skb); 1099 sk->sk_backlog.len += skb->truesize; 1100 return 0; 1101 } 1102 1103 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1104 1105 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)); 1106 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)); 1107 1108 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1109 { 1110 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1111 return __sk_backlog_rcv(sk, skb); 1112 1113 return INDIRECT_CALL_INET(sk->sk_backlog_rcv, 1114 tcp_v6_do_rcv, 1115 tcp_v4_do_rcv, 1116 sk, skb); 1117 } 1118 1119 static inline void sk_incoming_cpu_update(struct sock *sk) 1120 { 1121 int cpu = raw_smp_processor_id(); 1122 1123 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1124 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1125 } 1126 1127 static inline void sock_rps_record_flow_hash(__u32 hash) 1128 { 1129 #ifdef CONFIG_RPS 1130 struct rps_sock_flow_table *sock_flow_table; 1131 1132 rcu_read_lock(); 1133 sock_flow_table = rcu_dereference(rps_sock_flow_table); 1134 rps_record_sock_flow(sock_flow_table, hash); 1135 rcu_read_unlock(); 1136 #endif 1137 } 1138 1139 static inline void sock_rps_record_flow(const struct sock *sk) 1140 { 1141 #ifdef CONFIG_RPS 1142 if (static_branch_unlikely(&rfs_needed)) { 1143 /* Reading sk->sk_rxhash might incur an expensive cache line 1144 * miss. 1145 * 1146 * TCP_ESTABLISHED does cover almost all states where RFS 1147 * might be useful, and is cheaper [1] than testing : 1148 * IPv4: inet_sk(sk)->inet_daddr 1149 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 1150 * OR an additional socket flag 1151 * [1] : sk_state and sk_prot are in the same cache line. 1152 */ 1153 if (sk->sk_state == TCP_ESTABLISHED) 1154 sock_rps_record_flow_hash(sk->sk_rxhash); 1155 } 1156 #endif 1157 } 1158 1159 static inline void sock_rps_save_rxhash(struct sock *sk, 1160 const struct sk_buff *skb) 1161 { 1162 #ifdef CONFIG_RPS 1163 if (unlikely(sk->sk_rxhash != skb->hash)) 1164 sk->sk_rxhash = skb->hash; 1165 #endif 1166 } 1167 1168 static inline void sock_rps_reset_rxhash(struct sock *sk) 1169 { 1170 #ifdef CONFIG_RPS 1171 sk->sk_rxhash = 0; 1172 #endif 1173 } 1174 1175 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1176 ({ int __rc; \ 1177 release_sock(__sk); \ 1178 __rc = __condition; \ 1179 if (!__rc) { \ 1180 *(__timeo) = wait_woken(__wait, \ 1181 TASK_INTERRUPTIBLE, \ 1182 *(__timeo)); \ 1183 } \ 1184 sched_annotate_sleep(); \ 1185 lock_sock(__sk); \ 1186 __rc = __condition; \ 1187 __rc; \ 1188 }) 1189 1190 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1191 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1192 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1193 int sk_stream_error(struct sock *sk, int flags, int err); 1194 void sk_stream_kill_queues(struct sock *sk); 1195 void sk_set_memalloc(struct sock *sk); 1196 void sk_clear_memalloc(struct sock *sk); 1197 1198 void __sk_flush_backlog(struct sock *sk); 1199 1200 static inline bool sk_flush_backlog(struct sock *sk) 1201 { 1202 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1203 __sk_flush_backlog(sk); 1204 return true; 1205 } 1206 return false; 1207 } 1208 1209 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1210 1211 struct request_sock_ops; 1212 struct timewait_sock_ops; 1213 struct inet_hashinfo; 1214 struct raw_hashinfo; 1215 struct smc_hashinfo; 1216 struct module; 1217 struct sk_psock; 1218 1219 /* 1220 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1221 * un-modified. Special care is taken when initializing object to zero. 1222 */ 1223 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1224 { 1225 if (offsetof(struct sock, sk_node.next) != 0) 1226 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1227 memset(&sk->sk_node.pprev, 0, 1228 size - offsetof(struct sock, sk_node.pprev)); 1229 } 1230 1231 /* Networking protocol blocks we attach to sockets. 1232 * socket layer -> transport layer interface 1233 */ 1234 struct proto { 1235 void (*close)(struct sock *sk, 1236 long timeout); 1237 int (*pre_connect)(struct sock *sk, 1238 struct sockaddr *uaddr, 1239 int addr_len); 1240 int (*connect)(struct sock *sk, 1241 struct sockaddr *uaddr, 1242 int addr_len); 1243 int (*disconnect)(struct sock *sk, int flags); 1244 1245 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1246 bool kern); 1247 1248 int (*ioctl)(struct sock *sk, int cmd, 1249 unsigned long arg); 1250 int (*init)(struct sock *sk); 1251 void (*destroy)(struct sock *sk); 1252 void (*shutdown)(struct sock *sk, int how); 1253 int (*setsockopt)(struct sock *sk, int level, 1254 int optname, sockptr_t optval, 1255 unsigned int optlen); 1256 int (*getsockopt)(struct sock *sk, int level, 1257 int optname, char __user *optval, 1258 int __user *option); 1259 void (*keepalive)(struct sock *sk, int valbool); 1260 #ifdef CONFIG_COMPAT 1261 int (*compat_ioctl)(struct sock *sk, 1262 unsigned int cmd, unsigned long arg); 1263 #endif 1264 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1265 size_t len); 1266 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1267 size_t len, int flags, int *addr_len); 1268 int (*sendpage)(struct sock *sk, struct page *page, 1269 int offset, size_t size, int flags); 1270 int (*bind)(struct sock *sk, 1271 struct sockaddr *addr, int addr_len); 1272 int (*bind_add)(struct sock *sk, 1273 struct sockaddr *addr, int addr_len); 1274 1275 int (*backlog_rcv) (struct sock *sk, 1276 struct sk_buff *skb); 1277 bool (*bpf_bypass_getsockopt)(int level, 1278 int optname); 1279 1280 void (*release_cb)(struct sock *sk); 1281 1282 /* Keeping track of sk's, looking them up, and port selection methods. */ 1283 int (*hash)(struct sock *sk); 1284 void (*unhash)(struct sock *sk); 1285 void (*rehash)(struct sock *sk); 1286 int (*get_port)(struct sock *sk, unsigned short snum); 1287 void (*put_port)(struct sock *sk); 1288 #ifdef CONFIG_BPF_SYSCALL 1289 int (*psock_update_sk_prot)(struct sock *sk, 1290 struct sk_psock *psock, 1291 bool restore); 1292 #endif 1293 1294 /* Keeping track of sockets in use */ 1295 #ifdef CONFIG_PROC_FS 1296 unsigned int inuse_idx; 1297 #endif 1298 1299 #if IS_ENABLED(CONFIG_MPTCP) 1300 int (*forward_alloc_get)(const struct sock *sk); 1301 #endif 1302 1303 bool (*stream_memory_free)(const struct sock *sk, int wake); 1304 bool (*sock_is_readable)(struct sock *sk); 1305 /* Memory pressure */ 1306 void (*enter_memory_pressure)(struct sock *sk); 1307 void (*leave_memory_pressure)(struct sock *sk); 1308 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1309 int __percpu *per_cpu_fw_alloc; 1310 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1311 1312 /* 1313 * Pressure flag: try to collapse. 1314 * Technical note: it is used by multiple contexts non atomically. 1315 * All the __sk_mem_schedule() is of this nature: accounting 1316 * is strict, actions are advisory and have some latency. 1317 */ 1318 unsigned long *memory_pressure; 1319 long *sysctl_mem; 1320 1321 int *sysctl_wmem; 1322 int *sysctl_rmem; 1323 u32 sysctl_wmem_offset; 1324 u32 sysctl_rmem_offset; 1325 1326 int max_header; 1327 bool no_autobind; 1328 1329 struct kmem_cache *slab; 1330 unsigned int obj_size; 1331 slab_flags_t slab_flags; 1332 unsigned int useroffset; /* Usercopy region offset */ 1333 unsigned int usersize; /* Usercopy region size */ 1334 1335 unsigned int __percpu *orphan_count; 1336 1337 struct request_sock_ops *rsk_prot; 1338 struct timewait_sock_ops *twsk_prot; 1339 1340 union { 1341 struct inet_hashinfo *hashinfo; 1342 struct udp_table *udp_table; 1343 struct raw_hashinfo *raw_hash; 1344 struct smc_hashinfo *smc_hash; 1345 } h; 1346 1347 struct module *owner; 1348 1349 char name[32]; 1350 1351 struct list_head node; 1352 int (*diag_destroy)(struct sock *sk, int err); 1353 } __randomize_layout; 1354 1355 int proto_register(struct proto *prot, int alloc_slab); 1356 void proto_unregister(struct proto *prot); 1357 int sock_load_diag_module(int family, int protocol); 1358 1359 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1360 1361 static inline int sk_forward_alloc_get(const struct sock *sk) 1362 { 1363 #if IS_ENABLED(CONFIG_MPTCP) 1364 if (sk->sk_prot->forward_alloc_get) 1365 return sk->sk_prot->forward_alloc_get(sk); 1366 #endif 1367 return sk->sk_forward_alloc; 1368 } 1369 1370 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1371 { 1372 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1373 return false; 1374 1375 return sk->sk_prot->stream_memory_free ? 1376 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free, 1377 tcp_stream_memory_free, sk, wake) : true; 1378 } 1379 1380 static inline bool sk_stream_memory_free(const struct sock *sk) 1381 { 1382 return __sk_stream_memory_free(sk, 0); 1383 } 1384 1385 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1386 { 1387 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1388 __sk_stream_memory_free(sk, wake); 1389 } 1390 1391 static inline bool sk_stream_is_writeable(const struct sock *sk) 1392 { 1393 return __sk_stream_is_writeable(sk, 0); 1394 } 1395 1396 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1397 struct cgroup *ancestor) 1398 { 1399 #ifdef CONFIG_SOCK_CGROUP_DATA 1400 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1401 ancestor); 1402 #else 1403 return -ENOTSUPP; 1404 #endif 1405 } 1406 1407 static inline bool sk_has_memory_pressure(const struct sock *sk) 1408 { 1409 return sk->sk_prot->memory_pressure != NULL; 1410 } 1411 1412 static inline bool sk_under_memory_pressure(const struct sock *sk) 1413 { 1414 if (!sk->sk_prot->memory_pressure) 1415 return false; 1416 1417 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1418 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1419 return true; 1420 1421 return !!*sk->sk_prot->memory_pressure; 1422 } 1423 1424 static inline long 1425 proto_memory_allocated(const struct proto *prot) 1426 { 1427 return max(0L, atomic_long_read(prot->memory_allocated)); 1428 } 1429 1430 static inline long 1431 sk_memory_allocated(const struct sock *sk) 1432 { 1433 return proto_memory_allocated(sk->sk_prot); 1434 } 1435 1436 /* 1 MB per cpu, in page units */ 1437 #define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT)) 1438 1439 static inline void 1440 sk_memory_allocated_add(struct sock *sk, int amt) 1441 { 1442 int local_reserve; 1443 1444 preempt_disable(); 1445 local_reserve = __this_cpu_add_return(*sk->sk_prot->per_cpu_fw_alloc, amt); 1446 if (local_reserve >= SK_MEMORY_PCPU_RESERVE) { 1447 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve); 1448 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated); 1449 } 1450 preempt_enable(); 1451 } 1452 1453 static inline void 1454 sk_memory_allocated_sub(struct sock *sk, int amt) 1455 { 1456 int local_reserve; 1457 1458 preempt_disable(); 1459 local_reserve = __this_cpu_sub_return(*sk->sk_prot->per_cpu_fw_alloc, amt); 1460 if (local_reserve <= -SK_MEMORY_PCPU_RESERVE) { 1461 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve); 1462 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated); 1463 } 1464 preempt_enable(); 1465 } 1466 1467 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1468 1469 static inline void sk_sockets_allocated_dec(struct sock *sk) 1470 { 1471 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1472 SK_ALLOC_PERCPU_COUNTER_BATCH); 1473 } 1474 1475 static inline void sk_sockets_allocated_inc(struct sock *sk) 1476 { 1477 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1478 SK_ALLOC_PERCPU_COUNTER_BATCH); 1479 } 1480 1481 static inline u64 1482 sk_sockets_allocated_read_positive(struct sock *sk) 1483 { 1484 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1485 } 1486 1487 static inline int 1488 proto_sockets_allocated_sum_positive(struct proto *prot) 1489 { 1490 return percpu_counter_sum_positive(prot->sockets_allocated); 1491 } 1492 1493 static inline bool 1494 proto_memory_pressure(struct proto *prot) 1495 { 1496 if (!prot->memory_pressure) 1497 return false; 1498 return !!*prot->memory_pressure; 1499 } 1500 1501 1502 #ifdef CONFIG_PROC_FS 1503 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 1504 struct prot_inuse { 1505 int all; 1506 int val[PROTO_INUSE_NR]; 1507 }; 1508 1509 static inline void sock_prot_inuse_add(const struct net *net, 1510 const struct proto *prot, int val) 1511 { 1512 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 1513 } 1514 1515 static inline void sock_inuse_add(const struct net *net, int val) 1516 { 1517 this_cpu_add(net->core.prot_inuse->all, val); 1518 } 1519 1520 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1521 int sock_inuse_get(struct net *net); 1522 #else 1523 static inline void sock_prot_inuse_add(const struct net *net, 1524 const struct proto *prot, int val) 1525 { 1526 } 1527 1528 static inline void sock_inuse_add(const struct net *net, int val) 1529 { 1530 } 1531 #endif 1532 1533 1534 /* With per-bucket locks this operation is not-atomic, so that 1535 * this version is not worse. 1536 */ 1537 static inline int __sk_prot_rehash(struct sock *sk) 1538 { 1539 sk->sk_prot->unhash(sk); 1540 return sk->sk_prot->hash(sk); 1541 } 1542 1543 /* About 10 seconds */ 1544 #define SOCK_DESTROY_TIME (10*HZ) 1545 1546 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1547 #define PROT_SOCK 1024 1548 1549 #define SHUTDOWN_MASK 3 1550 #define RCV_SHUTDOWN 1 1551 #define SEND_SHUTDOWN 2 1552 1553 #define SOCK_BINDADDR_LOCK 4 1554 #define SOCK_BINDPORT_LOCK 8 1555 1556 struct socket_alloc { 1557 struct socket socket; 1558 struct inode vfs_inode; 1559 }; 1560 1561 static inline struct socket *SOCKET_I(struct inode *inode) 1562 { 1563 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1564 } 1565 1566 static inline struct inode *SOCK_INODE(struct socket *socket) 1567 { 1568 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1569 } 1570 1571 /* 1572 * Functions for memory accounting 1573 */ 1574 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1575 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1576 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1577 void __sk_mem_reclaim(struct sock *sk, int amount); 1578 1579 #define SK_MEM_SEND 0 1580 #define SK_MEM_RECV 1 1581 1582 /* sysctl_mem values are in pages */ 1583 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1584 { 1585 return READ_ONCE(sk->sk_prot->sysctl_mem[index]); 1586 } 1587 1588 static inline int sk_mem_pages(int amt) 1589 { 1590 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT; 1591 } 1592 1593 static inline bool sk_has_account(struct sock *sk) 1594 { 1595 /* return true if protocol supports memory accounting */ 1596 return !!sk->sk_prot->memory_allocated; 1597 } 1598 1599 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1600 { 1601 int delta; 1602 1603 if (!sk_has_account(sk)) 1604 return true; 1605 delta = size - sk->sk_forward_alloc; 1606 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND); 1607 } 1608 1609 static inline bool 1610 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1611 { 1612 int delta; 1613 1614 if (!sk_has_account(sk)) 1615 return true; 1616 delta = size - sk->sk_forward_alloc; 1617 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) || 1618 skb_pfmemalloc(skb); 1619 } 1620 1621 static inline int sk_unused_reserved_mem(const struct sock *sk) 1622 { 1623 int unused_mem; 1624 1625 if (likely(!sk->sk_reserved_mem)) 1626 return 0; 1627 1628 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued - 1629 atomic_read(&sk->sk_rmem_alloc); 1630 1631 return unused_mem > 0 ? unused_mem : 0; 1632 } 1633 1634 static inline void sk_mem_reclaim(struct sock *sk) 1635 { 1636 int reclaimable; 1637 1638 if (!sk_has_account(sk)) 1639 return; 1640 1641 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk); 1642 1643 if (reclaimable >= (int)PAGE_SIZE) 1644 __sk_mem_reclaim(sk, reclaimable); 1645 } 1646 1647 static inline void sk_mem_reclaim_final(struct sock *sk) 1648 { 1649 sk->sk_reserved_mem = 0; 1650 sk_mem_reclaim(sk); 1651 } 1652 1653 static inline void sk_mem_charge(struct sock *sk, int size) 1654 { 1655 if (!sk_has_account(sk)) 1656 return; 1657 sk->sk_forward_alloc -= size; 1658 } 1659 1660 static inline void sk_mem_uncharge(struct sock *sk, int size) 1661 { 1662 if (!sk_has_account(sk)) 1663 return; 1664 sk->sk_forward_alloc += size; 1665 sk_mem_reclaim(sk); 1666 } 1667 1668 /* 1669 * Macro so as to not evaluate some arguments when 1670 * lockdep is not enabled. 1671 * 1672 * Mark both the sk_lock and the sk_lock.slock as a 1673 * per-address-family lock class. 1674 */ 1675 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1676 do { \ 1677 sk->sk_lock.owned = 0; \ 1678 init_waitqueue_head(&sk->sk_lock.wq); \ 1679 spin_lock_init(&(sk)->sk_lock.slock); \ 1680 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1681 sizeof((sk)->sk_lock)); \ 1682 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1683 (skey), (sname)); \ 1684 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1685 } while (0) 1686 1687 static inline bool lockdep_sock_is_held(const struct sock *sk) 1688 { 1689 return lockdep_is_held(&sk->sk_lock) || 1690 lockdep_is_held(&sk->sk_lock.slock); 1691 } 1692 1693 void lock_sock_nested(struct sock *sk, int subclass); 1694 1695 static inline void lock_sock(struct sock *sk) 1696 { 1697 lock_sock_nested(sk, 0); 1698 } 1699 1700 void __lock_sock(struct sock *sk); 1701 void __release_sock(struct sock *sk); 1702 void release_sock(struct sock *sk); 1703 1704 /* BH context may only use the following locking interface. */ 1705 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1706 #define bh_lock_sock_nested(__sk) \ 1707 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1708 SINGLE_DEPTH_NESTING) 1709 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1710 1711 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1712 1713 /** 1714 * lock_sock_fast - fast version of lock_sock 1715 * @sk: socket 1716 * 1717 * This version should be used for very small section, where process wont block 1718 * return false if fast path is taken: 1719 * 1720 * sk_lock.slock locked, owned = 0, BH disabled 1721 * 1722 * return true if slow path is taken: 1723 * 1724 * sk_lock.slock unlocked, owned = 1, BH enabled 1725 */ 1726 static inline bool lock_sock_fast(struct sock *sk) 1727 { 1728 /* The sk_lock has mutex_lock() semantics here. */ 1729 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 1730 1731 return __lock_sock_fast(sk); 1732 } 1733 1734 /* fast socket lock variant for caller already holding a [different] socket lock */ 1735 static inline bool lock_sock_fast_nested(struct sock *sk) 1736 { 1737 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_); 1738 1739 return __lock_sock_fast(sk); 1740 } 1741 1742 /** 1743 * unlock_sock_fast - complement of lock_sock_fast 1744 * @sk: socket 1745 * @slow: slow mode 1746 * 1747 * fast unlock socket for user context. 1748 * If slow mode is on, we call regular release_sock() 1749 */ 1750 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1751 __releases(&sk->sk_lock.slock) 1752 { 1753 if (slow) { 1754 release_sock(sk); 1755 __release(&sk->sk_lock.slock); 1756 } else { 1757 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1758 spin_unlock_bh(&sk->sk_lock.slock); 1759 } 1760 } 1761 1762 void sockopt_lock_sock(struct sock *sk); 1763 void sockopt_release_sock(struct sock *sk); 1764 bool sockopt_ns_capable(struct user_namespace *ns, int cap); 1765 bool sockopt_capable(int cap); 1766 1767 /* Used by processes to "lock" a socket state, so that 1768 * interrupts and bottom half handlers won't change it 1769 * from under us. It essentially blocks any incoming 1770 * packets, so that we won't get any new data or any 1771 * packets that change the state of the socket. 1772 * 1773 * While locked, BH processing will add new packets to 1774 * the backlog queue. This queue is processed by the 1775 * owner of the socket lock right before it is released. 1776 * 1777 * Since ~2.3.5 it is also exclusive sleep lock serializing 1778 * accesses from user process context. 1779 */ 1780 1781 static inline void sock_owned_by_me(const struct sock *sk) 1782 { 1783 #ifdef CONFIG_LOCKDEP 1784 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1785 #endif 1786 } 1787 1788 static inline bool sock_owned_by_user(const struct sock *sk) 1789 { 1790 sock_owned_by_me(sk); 1791 return sk->sk_lock.owned; 1792 } 1793 1794 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1795 { 1796 return sk->sk_lock.owned; 1797 } 1798 1799 static inline void sock_release_ownership(struct sock *sk) 1800 { 1801 if (sock_owned_by_user_nocheck(sk)) { 1802 sk->sk_lock.owned = 0; 1803 1804 /* The sk_lock has mutex_unlock() semantics: */ 1805 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1806 } 1807 } 1808 1809 /* no reclassification while locks are held */ 1810 static inline bool sock_allow_reclassification(const struct sock *csk) 1811 { 1812 struct sock *sk = (struct sock *)csk; 1813 1814 return !sock_owned_by_user_nocheck(sk) && 1815 !spin_is_locked(&sk->sk_lock.slock); 1816 } 1817 1818 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1819 struct proto *prot, int kern); 1820 void sk_free(struct sock *sk); 1821 void sk_destruct(struct sock *sk); 1822 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1823 void sk_free_unlock_clone(struct sock *sk); 1824 1825 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1826 gfp_t priority); 1827 void __sock_wfree(struct sk_buff *skb); 1828 void sock_wfree(struct sk_buff *skb); 1829 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1830 gfp_t priority); 1831 void skb_orphan_partial(struct sk_buff *skb); 1832 void sock_rfree(struct sk_buff *skb); 1833 void sock_efree(struct sk_buff *skb); 1834 #ifdef CONFIG_INET 1835 void sock_edemux(struct sk_buff *skb); 1836 void sock_pfree(struct sk_buff *skb); 1837 #else 1838 #define sock_edemux sock_efree 1839 #endif 1840 1841 int sk_setsockopt(struct sock *sk, int level, int optname, 1842 sockptr_t optval, unsigned int optlen); 1843 int sock_setsockopt(struct socket *sock, int level, int op, 1844 sockptr_t optval, unsigned int optlen); 1845 1846 int sk_getsockopt(struct sock *sk, int level, int optname, 1847 sockptr_t optval, sockptr_t optlen); 1848 int sock_getsockopt(struct socket *sock, int level, int op, 1849 char __user *optval, int __user *optlen); 1850 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1851 bool timeval, bool time32); 1852 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1853 unsigned long data_len, int noblock, 1854 int *errcode, int max_page_order); 1855 1856 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1857 unsigned long size, 1858 int noblock, int *errcode) 1859 { 1860 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1861 } 1862 1863 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1864 void sock_kfree_s(struct sock *sk, void *mem, int size); 1865 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1866 void sk_send_sigurg(struct sock *sk); 1867 1868 static inline void sock_replace_proto(struct sock *sk, struct proto *proto) 1869 { 1870 if (sk->sk_socket) 1871 clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1872 WRITE_ONCE(sk->sk_prot, proto); 1873 } 1874 1875 struct sockcm_cookie { 1876 u64 transmit_time; 1877 u32 mark; 1878 u32 tsflags; 1879 }; 1880 1881 static inline void sockcm_init(struct sockcm_cookie *sockc, 1882 const struct sock *sk) 1883 { 1884 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1885 } 1886 1887 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 1888 struct sockcm_cookie *sockc); 1889 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1890 struct sockcm_cookie *sockc); 1891 1892 /* 1893 * Functions to fill in entries in struct proto_ops when a protocol 1894 * does not implement a particular function. 1895 */ 1896 int sock_no_bind(struct socket *, struct sockaddr *, int); 1897 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1898 int sock_no_socketpair(struct socket *, struct socket *); 1899 int sock_no_accept(struct socket *, struct socket *, int, bool); 1900 int sock_no_getname(struct socket *, struct sockaddr *, int); 1901 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1902 int sock_no_listen(struct socket *, int); 1903 int sock_no_shutdown(struct socket *, int); 1904 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1905 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1906 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1907 int sock_no_mmap(struct file *file, struct socket *sock, 1908 struct vm_area_struct *vma); 1909 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1910 size_t size, int flags); 1911 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1912 int offset, size_t size, int flags); 1913 1914 /* 1915 * Functions to fill in entries in struct proto_ops when a protocol 1916 * uses the inet style. 1917 */ 1918 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1919 char __user *optval, int __user *optlen); 1920 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1921 int flags); 1922 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1923 sockptr_t optval, unsigned int optlen); 1924 1925 void sk_common_release(struct sock *sk); 1926 1927 /* 1928 * Default socket callbacks and setup code 1929 */ 1930 1931 /* Initialise core socket variables using an explicit uid. */ 1932 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid); 1933 1934 /* Initialise core socket variables. 1935 * Assumes struct socket *sock is embedded in a struct socket_alloc. 1936 */ 1937 void sock_init_data(struct socket *sock, struct sock *sk); 1938 1939 /* 1940 * Socket reference counting postulates. 1941 * 1942 * * Each user of socket SHOULD hold a reference count. 1943 * * Each access point to socket (an hash table bucket, reference from a list, 1944 * running timer, skb in flight MUST hold a reference count. 1945 * * When reference count hits 0, it means it will never increase back. 1946 * * When reference count hits 0, it means that no references from 1947 * outside exist to this socket and current process on current CPU 1948 * is last user and may/should destroy this socket. 1949 * * sk_free is called from any context: process, BH, IRQ. When 1950 * it is called, socket has no references from outside -> sk_free 1951 * may release descendant resources allocated by the socket, but 1952 * to the time when it is called, socket is NOT referenced by any 1953 * hash tables, lists etc. 1954 * * Packets, delivered from outside (from network or from another process) 1955 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1956 * when they sit in queue. Otherwise, packets will leak to hole, when 1957 * socket is looked up by one cpu and unhasing is made by another CPU. 1958 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1959 * (leak to backlog). Packet socket does all the processing inside 1960 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1961 * use separate SMP lock, so that they are prone too. 1962 */ 1963 1964 /* Ungrab socket and destroy it, if it was the last reference. */ 1965 static inline void sock_put(struct sock *sk) 1966 { 1967 if (refcount_dec_and_test(&sk->sk_refcnt)) 1968 sk_free(sk); 1969 } 1970 /* Generic version of sock_put(), dealing with all sockets 1971 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1972 */ 1973 void sock_gen_put(struct sock *sk); 1974 1975 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1976 unsigned int trim_cap, bool refcounted); 1977 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1978 const int nested) 1979 { 1980 return __sk_receive_skb(sk, skb, nested, 1, true); 1981 } 1982 1983 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1984 { 1985 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1986 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1987 return; 1988 sk->sk_tx_queue_mapping = tx_queue; 1989 } 1990 1991 #define NO_QUEUE_MAPPING USHRT_MAX 1992 1993 static inline void sk_tx_queue_clear(struct sock *sk) 1994 { 1995 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1996 } 1997 1998 static inline int sk_tx_queue_get(const struct sock *sk) 1999 { 2000 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 2001 return sk->sk_tx_queue_mapping; 2002 2003 return -1; 2004 } 2005 2006 static inline void __sk_rx_queue_set(struct sock *sk, 2007 const struct sk_buff *skb, 2008 bool force_set) 2009 { 2010 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2011 if (skb_rx_queue_recorded(skb)) { 2012 u16 rx_queue = skb_get_rx_queue(skb); 2013 2014 if (force_set || 2015 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) 2016 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue); 2017 } 2018 #endif 2019 } 2020 2021 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 2022 { 2023 __sk_rx_queue_set(sk, skb, true); 2024 } 2025 2026 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb) 2027 { 2028 __sk_rx_queue_set(sk, skb, false); 2029 } 2030 2031 static inline void sk_rx_queue_clear(struct sock *sk) 2032 { 2033 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2034 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING); 2035 #endif 2036 } 2037 2038 static inline int sk_rx_queue_get(const struct sock *sk) 2039 { 2040 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2041 if (sk) { 2042 int res = READ_ONCE(sk->sk_rx_queue_mapping); 2043 2044 if (res != NO_QUEUE_MAPPING) 2045 return res; 2046 } 2047 #endif 2048 2049 return -1; 2050 } 2051 2052 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 2053 { 2054 sk->sk_socket = sock; 2055 } 2056 2057 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 2058 { 2059 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 2060 return &rcu_dereference_raw(sk->sk_wq)->wait; 2061 } 2062 /* Detach socket from process context. 2063 * Announce socket dead, detach it from wait queue and inode. 2064 * Note that parent inode held reference count on this struct sock, 2065 * we do not release it in this function, because protocol 2066 * probably wants some additional cleanups or even continuing 2067 * to work with this socket (TCP). 2068 */ 2069 static inline void sock_orphan(struct sock *sk) 2070 { 2071 write_lock_bh(&sk->sk_callback_lock); 2072 sock_set_flag(sk, SOCK_DEAD); 2073 sk_set_socket(sk, NULL); 2074 sk->sk_wq = NULL; 2075 write_unlock_bh(&sk->sk_callback_lock); 2076 } 2077 2078 static inline void sock_graft(struct sock *sk, struct socket *parent) 2079 { 2080 WARN_ON(parent->sk); 2081 write_lock_bh(&sk->sk_callback_lock); 2082 rcu_assign_pointer(sk->sk_wq, &parent->wq); 2083 parent->sk = sk; 2084 sk_set_socket(sk, parent); 2085 sk->sk_uid = SOCK_INODE(parent)->i_uid; 2086 security_sock_graft(sk, parent); 2087 write_unlock_bh(&sk->sk_callback_lock); 2088 } 2089 2090 kuid_t sock_i_uid(struct sock *sk); 2091 unsigned long sock_i_ino(struct sock *sk); 2092 2093 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 2094 { 2095 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 2096 } 2097 2098 static inline u32 net_tx_rndhash(void) 2099 { 2100 u32 v = get_random_u32(); 2101 2102 return v ?: 1; 2103 } 2104 2105 static inline void sk_set_txhash(struct sock *sk) 2106 { 2107 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */ 2108 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash()); 2109 } 2110 2111 static inline bool sk_rethink_txhash(struct sock *sk) 2112 { 2113 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) { 2114 sk_set_txhash(sk); 2115 return true; 2116 } 2117 return false; 2118 } 2119 2120 static inline struct dst_entry * 2121 __sk_dst_get(struct sock *sk) 2122 { 2123 return rcu_dereference_check(sk->sk_dst_cache, 2124 lockdep_sock_is_held(sk)); 2125 } 2126 2127 static inline struct dst_entry * 2128 sk_dst_get(struct sock *sk) 2129 { 2130 struct dst_entry *dst; 2131 2132 rcu_read_lock(); 2133 dst = rcu_dereference(sk->sk_dst_cache); 2134 if (dst && !rcuref_get(&dst->__rcuref)) 2135 dst = NULL; 2136 rcu_read_unlock(); 2137 return dst; 2138 } 2139 2140 static inline void __dst_negative_advice(struct sock *sk) 2141 { 2142 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 2143 2144 if (dst && dst->ops->negative_advice) { 2145 ndst = dst->ops->negative_advice(dst); 2146 2147 if (ndst != dst) { 2148 rcu_assign_pointer(sk->sk_dst_cache, ndst); 2149 sk_tx_queue_clear(sk); 2150 sk->sk_dst_pending_confirm = 0; 2151 } 2152 } 2153 } 2154 2155 static inline void dst_negative_advice(struct sock *sk) 2156 { 2157 sk_rethink_txhash(sk); 2158 __dst_negative_advice(sk); 2159 } 2160 2161 static inline void 2162 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 2163 { 2164 struct dst_entry *old_dst; 2165 2166 sk_tx_queue_clear(sk); 2167 sk->sk_dst_pending_confirm = 0; 2168 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 2169 lockdep_sock_is_held(sk)); 2170 rcu_assign_pointer(sk->sk_dst_cache, dst); 2171 dst_release(old_dst); 2172 } 2173 2174 static inline void 2175 sk_dst_set(struct sock *sk, struct dst_entry *dst) 2176 { 2177 struct dst_entry *old_dst; 2178 2179 sk_tx_queue_clear(sk); 2180 sk->sk_dst_pending_confirm = 0; 2181 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 2182 dst_release(old_dst); 2183 } 2184 2185 static inline void 2186 __sk_dst_reset(struct sock *sk) 2187 { 2188 __sk_dst_set(sk, NULL); 2189 } 2190 2191 static inline void 2192 sk_dst_reset(struct sock *sk) 2193 { 2194 sk_dst_set(sk, NULL); 2195 } 2196 2197 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2198 2199 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2200 2201 static inline void sk_dst_confirm(struct sock *sk) 2202 { 2203 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2204 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2205 } 2206 2207 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2208 { 2209 if (skb_get_dst_pending_confirm(skb)) { 2210 struct sock *sk = skb->sk; 2211 2212 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2213 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2214 neigh_confirm(n); 2215 } 2216 } 2217 2218 bool sk_mc_loop(struct sock *sk); 2219 2220 static inline bool sk_can_gso(const struct sock *sk) 2221 { 2222 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2223 } 2224 2225 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2226 2227 static inline void sk_gso_disable(struct sock *sk) 2228 { 2229 sk->sk_gso_disabled = 1; 2230 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2231 } 2232 2233 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2234 struct iov_iter *from, char *to, 2235 int copy, int offset) 2236 { 2237 if (skb->ip_summed == CHECKSUM_NONE) { 2238 __wsum csum = 0; 2239 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2240 return -EFAULT; 2241 skb->csum = csum_block_add(skb->csum, csum, offset); 2242 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2243 if (!copy_from_iter_full_nocache(to, copy, from)) 2244 return -EFAULT; 2245 } else if (!copy_from_iter_full(to, copy, from)) 2246 return -EFAULT; 2247 2248 return 0; 2249 } 2250 2251 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2252 struct iov_iter *from, int copy) 2253 { 2254 int err, offset = skb->len; 2255 2256 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2257 copy, offset); 2258 if (err) 2259 __skb_trim(skb, offset); 2260 2261 return err; 2262 } 2263 2264 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2265 struct sk_buff *skb, 2266 struct page *page, 2267 int off, int copy) 2268 { 2269 int err; 2270 2271 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2272 copy, skb->len); 2273 if (err) 2274 return err; 2275 2276 skb_len_add(skb, copy); 2277 sk_wmem_queued_add(sk, copy); 2278 sk_mem_charge(sk, copy); 2279 return 0; 2280 } 2281 2282 /** 2283 * sk_wmem_alloc_get - returns write allocations 2284 * @sk: socket 2285 * 2286 * Return: sk_wmem_alloc minus initial offset of one 2287 */ 2288 static inline int sk_wmem_alloc_get(const struct sock *sk) 2289 { 2290 return refcount_read(&sk->sk_wmem_alloc) - 1; 2291 } 2292 2293 /** 2294 * sk_rmem_alloc_get - returns read allocations 2295 * @sk: socket 2296 * 2297 * Return: sk_rmem_alloc 2298 */ 2299 static inline int sk_rmem_alloc_get(const struct sock *sk) 2300 { 2301 return atomic_read(&sk->sk_rmem_alloc); 2302 } 2303 2304 /** 2305 * sk_has_allocations - check if allocations are outstanding 2306 * @sk: socket 2307 * 2308 * Return: true if socket has write or read allocations 2309 */ 2310 static inline bool sk_has_allocations(const struct sock *sk) 2311 { 2312 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2313 } 2314 2315 /** 2316 * skwq_has_sleeper - check if there are any waiting processes 2317 * @wq: struct socket_wq 2318 * 2319 * Return: true if socket_wq has waiting processes 2320 * 2321 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2322 * barrier call. They were added due to the race found within the tcp code. 2323 * 2324 * Consider following tcp code paths:: 2325 * 2326 * CPU1 CPU2 2327 * sys_select receive packet 2328 * ... ... 2329 * __add_wait_queue update tp->rcv_nxt 2330 * ... ... 2331 * tp->rcv_nxt check sock_def_readable 2332 * ... { 2333 * schedule rcu_read_lock(); 2334 * wq = rcu_dereference(sk->sk_wq); 2335 * if (wq && waitqueue_active(&wq->wait)) 2336 * wake_up_interruptible(&wq->wait) 2337 * ... 2338 * } 2339 * 2340 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2341 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2342 * could then endup calling schedule and sleep forever if there are no more 2343 * data on the socket. 2344 * 2345 */ 2346 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2347 { 2348 return wq && wq_has_sleeper(&wq->wait); 2349 } 2350 2351 /** 2352 * sock_poll_wait - place memory barrier behind the poll_wait call. 2353 * @filp: file 2354 * @sock: socket to wait on 2355 * @p: poll_table 2356 * 2357 * See the comments in the wq_has_sleeper function. 2358 */ 2359 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2360 poll_table *p) 2361 { 2362 if (!poll_does_not_wait(p)) { 2363 poll_wait(filp, &sock->wq.wait, p); 2364 /* We need to be sure we are in sync with the 2365 * socket flags modification. 2366 * 2367 * This memory barrier is paired in the wq_has_sleeper. 2368 */ 2369 smp_mb(); 2370 } 2371 } 2372 2373 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2374 { 2375 /* This pairs with WRITE_ONCE() in sk_set_txhash() */ 2376 u32 txhash = READ_ONCE(sk->sk_txhash); 2377 2378 if (txhash) { 2379 skb->l4_hash = 1; 2380 skb->hash = txhash; 2381 } 2382 } 2383 2384 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2385 2386 /* 2387 * Queue a received datagram if it will fit. Stream and sequenced 2388 * protocols can't normally use this as they need to fit buffers in 2389 * and play with them. 2390 * 2391 * Inlined as it's very short and called for pretty much every 2392 * packet ever received. 2393 */ 2394 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2395 { 2396 skb_orphan(skb); 2397 skb->sk = sk; 2398 skb->destructor = sock_rfree; 2399 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2400 sk_mem_charge(sk, skb->truesize); 2401 } 2402 2403 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2404 { 2405 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2406 skb_orphan(skb); 2407 skb->destructor = sock_efree; 2408 skb->sk = sk; 2409 return true; 2410 } 2411 return false; 2412 } 2413 2414 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) 2415 { 2416 skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 2417 if (skb) { 2418 if (sk_rmem_schedule(sk, skb, skb->truesize)) { 2419 skb_set_owner_r(skb, sk); 2420 return skb; 2421 } 2422 __kfree_skb(skb); 2423 } 2424 return NULL; 2425 } 2426 2427 static inline void skb_prepare_for_gro(struct sk_buff *skb) 2428 { 2429 if (skb->destructor != sock_wfree) { 2430 skb_orphan(skb); 2431 return; 2432 } 2433 skb->slow_gro = 1; 2434 } 2435 2436 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2437 unsigned long expires); 2438 2439 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2440 2441 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2442 2443 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2444 struct sk_buff *skb, unsigned int flags, 2445 void (*destructor)(struct sock *sk, 2446 struct sk_buff *skb)); 2447 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2448 2449 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 2450 enum skb_drop_reason *reason); 2451 2452 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 2453 { 2454 return sock_queue_rcv_skb_reason(sk, skb, NULL); 2455 } 2456 2457 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2458 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2459 2460 /* 2461 * Recover an error report and clear atomically 2462 */ 2463 2464 static inline int sock_error(struct sock *sk) 2465 { 2466 int err; 2467 2468 /* Avoid an atomic operation for the common case. 2469 * This is racy since another cpu/thread can change sk_err under us. 2470 */ 2471 if (likely(data_race(!sk->sk_err))) 2472 return 0; 2473 2474 err = xchg(&sk->sk_err, 0); 2475 return -err; 2476 } 2477 2478 void sk_error_report(struct sock *sk); 2479 2480 static inline unsigned long sock_wspace(struct sock *sk) 2481 { 2482 int amt = 0; 2483 2484 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2485 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2486 if (amt < 0) 2487 amt = 0; 2488 } 2489 return amt; 2490 } 2491 2492 /* Note: 2493 * We use sk->sk_wq_raw, from contexts knowing this 2494 * pointer is not NULL and cannot disappear/change. 2495 */ 2496 static inline void sk_set_bit(int nr, struct sock *sk) 2497 { 2498 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2499 !sock_flag(sk, SOCK_FASYNC)) 2500 return; 2501 2502 set_bit(nr, &sk->sk_wq_raw->flags); 2503 } 2504 2505 static inline void sk_clear_bit(int nr, struct sock *sk) 2506 { 2507 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2508 !sock_flag(sk, SOCK_FASYNC)) 2509 return; 2510 2511 clear_bit(nr, &sk->sk_wq_raw->flags); 2512 } 2513 2514 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2515 { 2516 if (sock_flag(sk, SOCK_FASYNC)) { 2517 rcu_read_lock(); 2518 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2519 rcu_read_unlock(); 2520 } 2521 } 2522 2523 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2524 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2525 * Note: for send buffers, TCP works better if we can build two skbs at 2526 * minimum. 2527 */ 2528 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2529 2530 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2531 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2532 2533 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2534 { 2535 u32 val; 2536 2537 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2538 return; 2539 2540 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2541 val = max_t(u32, val, sk_unused_reserved_mem(sk)); 2542 2543 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2544 } 2545 2546 /** 2547 * sk_page_frag - return an appropriate page_frag 2548 * @sk: socket 2549 * 2550 * Use the per task page_frag instead of the per socket one for 2551 * optimization when we know that we're in process context and own 2552 * everything that's associated with %current. 2553 * 2554 * Both direct reclaim and page faults can nest inside other 2555 * socket operations and end up recursing into sk_page_frag() 2556 * while it's already in use: explicitly avoid task page_frag 2557 * when users disable sk_use_task_frag. 2558 * 2559 * Return: a per task page_frag if context allows that, 2560 * otherwise a per socket one. 2561 */ 2562 static inline struct page_frag *sk_page_frag(struct sock *sk) 2563 { 2564 if (sk->sk_use_task_frag) 2565 return ¤t->task_frag; 2566 2567 return &sk->sk_frag; 2568 } 2569 2570 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2571 2572 /* 2573 * Default write policy as shown to user space via poll/select/SIGIO 2574 */ 2575 static inline bool sock_writeable(const struct sock *sk) 2576 { 2577 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2578 } 2579 2580 static inline gfp_t gfp_any(void) 2581 { 2582 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2583 } 2584 2585 static inline gfp_t gfp_memcg_charge(void) 2586 { 2587 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2588 } 2589 2590 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2591 { 2592 return noblock ? 0 : sk->sk_rcvtimeo; 2593 } 2594 2595 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2596 { 2597 return noblock ? 0 : sk->sk_sndtimeo; 2598 } 2599 2600 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2601 { 2602 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2603 2604 return v ?: 1; 2605 } 2606 2607 /* Alas, with timeout socket operations are not restartable. 2608 * Compare this to poll(). 2609 */ 2610 static inline int sock_intr_errno(long timeo) 2611 { 2612 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2613 } 2614 2615 struct sock_skb_cb { 2616 u32 dropcount; 2617 }; 2618 2619 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2620 * using skb->cb[] would keep using it directly and utilize its 2621 * alignement guarantee. 2622 */ 2623 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2624 sizeof(struct sock_skb_cb))) 2625 2626 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2627 SOCK_SKB_CB_OFFSET)) 2628 2629 #define sock_skb_cb_check_size(size) \ 2630 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2631 2632 static inline void 2633 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2634 { 2635 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2636 atomic_read(&sk->sk_drops) : 0; 2637 } 2638 2639 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2640 { 2641 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2642 2643 atomic_add(segs, &sk->sk_drops); 2644 } 2645 2646 static inline ktime_t sock_read_timestamp(struct sock *sk) 2647 { 2648 #if BITS_PER_LONG==32 2649 unsigned int seq; 2650 ktime_t kt; 2651 2652 do { 2653 seq = read_seqbegin(&sk->sk_stamp_seq); 2654 kt = sk->sk_stamp; 2655 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2656 2657 return kt; 2658 #else 2659 return READ_ONCE(sk->sk_stamp); 2660 #endif 2661 } 2662 2663 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2664 { 2665 #if BITS_PER_LONG==32 2666 write_seqlock(&sk->sk_stamp_seq); 2667 sk->sk_stamp = kt; 2668 write_sequnlock(&sk->sk_stamp_seq); 2669 #else 2670 WRITE_ONCE(sk->sk_stamp, kt); 2671 #endif 2672 } 2673 2674 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2675 struct sk_buff *skb); 2676 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2677 struct sk_buff *skb); 2678 2679 static inline void 2680 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2681 { 2682 ktime_t kt = skb->tstamp; 2683 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2684 2685 /* 2686 * generate control messages if 2687 * - receive time stamping in software requested 2688 * - software time stamp available and wanted 2689 * - hardware time stamps available and wanted 2690 */ 2691 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2692 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2693 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2694 (hwtstamps->hwtstamp && 2695 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2696 __sock_recv_timestamp(msg, sk, skb); 2697 else 2698 sock_write_timestamp(sk, kt); 2699 2700 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb)) 2701 __sock_recv_wifi_status(msg, sk, skb); 2702 } 2703 2704 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2705 struct sk_buff *skb); 2706 2707 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2708 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2709 struct sk_buff *skb) 2710 { 2711 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \ 2712 (1UL << SOCK_RCVTSTAMP) | \ 2713 (1UL << SOCK_RCVMARK)) 2714 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2715 SOF_TIMESTAMPING_RAW_HARDWARE) 2716 2717 if (sk->sk_flags & FLAGS_RECV_CMSGS || sk->sk_tsflags & TSFLAGS_ANY) 2718 __sock_recv_cmsgs(msg, sk, skb); 2719 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2720 sock_write_timestamp(sk, skb->tstamp); 2721 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP)) 2722 sock_write_timestamp(sk, 0); 2723 } 2724 2725 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2726 2727 /** 2728 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2729 * @sk: socket sending this packet 2730 * @tsflags: timestamping flags to use 2731 * @tx_flags: completed with instructions for time stamping 2732 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2733 * 2734 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2735 */ 2736 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2737 __u8 *tx_flags, __u32 *tskey) 2738 { 2739 if (unlikely(tsflags)) { 2740 __sock_tx_timestamp(tsflags, tx_flags); 2741 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2742 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2743 *tskey = atomic_inc_return(&sk->sk_tskey) - 1; 2744 } 2745 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2746 *tx_flags |= SKBTX_WIFI_STATUS; 2747 } 2748 2749 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2750 __u8 *tx_flags) 2751 { 2752 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2753 } 2754 2755 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2756 { 2757 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2758 &skb_shinfo(skb)->tskey); 2759 } 2760 2761 static inline bool sk_is_tcp(const struct sock *sk) 2762 { 2763 return sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP; 2764 } 2765 2766 /** 2767 * sk_eat_skb - Release a skb if it is no longer needed 2768 * @sk: socket to eat this skb from 2769 * @skb: socket buffer to eat 2770 * 2771 * This routine must be called with interrupts disabled or with the socket 2772 * locked so that the sk_buff queue operation is ok. 2773 */ 2774 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2775 { 2776 __skb_unlink(skb, &sk->sk_receive_queue); 2777 __kfree_skb(skb); 2778 } 2779 2780 static inline bool 2781 skb_sk_is_prefetched(struct sk_buff *skb) 2782 { 2783 #ifdef CONFIG_INET 2784 return skb->destructor == sock_pfree; 2785 #else 2786 return false; 2787 #endif /* CONFIG_INET */ 2788 } 2789 2790 /* This helper checks if a socket is a full socket, 2791 * ie _not_ a timewait or request socket. 2792 */ 2793 static inline bool sk_fullsock(const struct sock *sk) 2794 { 2795 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2796 } 2797 2798 static inline bool 2799 sk_is_refcounted(struct sock *sk) 2800 { 2801 /* Only full sockets have sk->sk_flags. */ 2802 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2803 } 2804 2805 /** 2806 * skb_steal_sock - steal a socket from an sk_buff 2807 * @skb: sk_buff to steal the socket from 2808 * @refcounted: is set to true if the socket is reference-counted 2809 */ 2810 static inline struct sock * 2811 skb_steal_sock(struct sk_buff *skb, bool *refcounted) 2812 { 2813 if (skb->sk) { 2814 struct sock *sk = skb->sk; 2815 2816 *refcounted = true; 2817 if (skb_sk_is_prefetched(skb)) 2818 *refcounted = sk_is_refcounted(sk); 2819 skb->destructor = NULL; 2820 skb->sk = NULL; 2821 return sk; 2822 } 2823 *refcounted = false; 2824 return NULL; 2825 } 2826 2827 /* Checks if this SKB belongs to an HW offloaded socket 2828 * and whether any SW fallbacks are required based on dev. 2829 * Check decrypted mark in case skb_orphan() cleared socket. 2830 */ 2831 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2832 struct net_device *dev) 2833 { 2834 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2835 struct sock *sk = skb->sk; 2836 2837 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2838 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2839 #ifdef CONFIG_TLS_DEVICE 2840 } else if (unlikely(skb->decrypted)) { 2841 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2842 kfree_skb(skb); 2843 skb = NULL; 2844 #endif 2845 } 2846 #endif 2847 2848 return skb; 2849 } 2850 2851 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2852 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2853 */ 2854 static inline bool sk_listener(const struct sock *sk) 2855 { 2856 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2857 } 2858 2859 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2860 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2861 int type); 2862 2863 bool sk_ns_capable(const struct sock *sk, 2864 struct user_namespace *user_ns, int cap); 2865 bool sk_capable(const struct sock *sk, int cap); 2866 bool sk_net_capable(const struct sock *sk, int cap); 2867 2868 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2869 2870 /* Take into consideration the size of the struct sk_buff overhead in the 2871 * determination of these values, since that is non-constant across 2872 * platforms. This makes socket queueing behavior and performance 2873 * not depend upon such differences. 2874 */ 2875 #define _SK_MEM_PACKETS 256 2876 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2877 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2878 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2879 2880 extern __u32 sysctl_wmem_max; 2881 extern __u32 sysctl_rmem_max; 2882 2883 extern int sysctl_tstamp_allow_data; 2884 extern int sysctl_optmem_max; 2885 2886 extern __u32 sysctl_wmem_default; 2887 extern __u32 sysctl_rmem_default; 2888 2889 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2890 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2891 2892 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2893 { 2894 /* Does this proto have per netns sysctl_wmem ? */ 2895 if (proto->sysctl_wmem_offset) 2896 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); 2897 2898 return READ_ONCE(*proto->sysctl_wmem); 2899 } 2900 2901 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2902 { 2903 /* Does this proto have per netns sysctl_rmem ? */ 2904 if (proto->sysctl_rmem_offset) 2905 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); 2906 2907 return READ_ONCE(*proto->sysctl_rmem); 2908 } 2909 2910 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2911 * Some wifi drivers need to tweak it to get more chunks. 2912 * They can use this helper from their ndo_start_xmit() 2913 */ 2914 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2915 { 2916 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2917 return; 2918 WRITE_ONCE(sk->sk_pacing_shift, val); 2919 } 2920 2921 /* if a socket is bound to a device, check that the given device 2922 * index is either the same or that the socket is bound to an L3 2923 * master device and the given device index is also enslaved to 2924 * that L3 master 2925 */ 2926 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2927 { 2928 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 2929 int mdif; 2930 2931 if (!bound_dev_if || bound_dev_if == dif) 2932 return true; 2933 2934 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2935 if (mdif && mdif == bound_dev_if) 2936 return true; 2937 2938 return false; 2939 } 2940 2941 void sock_def_readable(struct sock *sk); 2942 2943 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 2944 void sock_set_timestamp(struct sock *sk, int optname, bool valbool); 2945 int sock_set_timestamping(struct sock *sk, int optname, 2946 struct so_timestamping timestamping); 2947 2948 void sock_enable_timestamps(struct sock *sk); 2949 void sock_no_linger(struct sock *sk); 2950 void sock_set_keepalive(struct sock *sk); 2951 void sock_set_priority(struct sock *sk, u32 priority); 2952 void sock_set_rcvbuf(struct sock *sk, int val); 2953 void sock_set_mark(struct sock *sk, u32 val); 2954 void sock_set_reuseaddr(struct sock *sk); 2955 void sock_set_reuseport(struct sock *sk); 2956 void sock_set_sndtimeo(struct sock *sk, s64 secs); 2957 2958 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 2959 2960 int sock_get_timeout(long timeo, void *optval, bool old_timeval); 2961 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 2962 sockptr_t optval, int optlen, bool old_timeval); 2963 2964 static inline bool sk_is_readable(struct sock *sk) 2965 { 2966 if (sk->sk_prot->sock_is_readable) 2967 return sk->sk_prot->sock_is_readable(sk); 2968 return false; 2969 } 2970 #endif /* _SOCK_H */ 2971