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_disconnects: number of disconnect operations performed on this sock 340 * @sk_state_change: callback to indicate change in the state of the sock 341 * @sk_data_ready: callback to indicate there is data to be processed 342 * @sk_write_space: callback to indicate there is bf sending space available 343 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 344 * @sk_backlog_rcv: callback to process the backlog 345 * @sk_validate_xmit_skb: ptr to an optional validate function 346 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 347 * @sk_reuseport_cb: reuseport group container 348 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage 349 * @sk_rcu: used during RCU grace period 350 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 351 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 352 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME 353 * @sk_txtime_unused: unused txtime flags 354 * @ns_tracker: tracker for netns reference 355 * @sk_bind2_node: bind node in the bhash2 table 356 */ 357 struct sock { 358 /* 359 * Now struct inet_timewait_sock also uses sock_common, so please just 360 * don't add nothing before this first member (__sk_common) --acme 361 */ 362 struct sock_common __sk_common; 363 #define sk_node __sk_common.skc_node 364 #define sk_nulls_node __sk_common.skc_nulls_node 365 #define sk_refcnt __sk_common.skc_refcnt 366 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 367 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 368 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 369 #endif 370 371 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 372 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 373 #define sk_hash __sk_common.skc_hash 374 #define sk_portpair __sk_common.skc_portpair 375 #define sk_num __sk_common.skc_num 376 #define sk_dport __sk_common.skc_dport 377 #define sk_addrpair __sk_common.skc_addrpair 378 #define sk_daddr __sk_common.skc_daddr 379 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 380 #define sk_family __sk_common.skc_family 381 #define sk_state __sk_common.skc_state 382 #define sk_reuse __sk_common.skc_reuse 383 #define sk_reuseport __sk_common.skc_reuseport 384 #define sk_ipv6only __sk_common.skc_ipv6only 385 #define sk_net_refcnt __sk_common.skc_net_refcnt 386 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 387 #define sk_bind_node __sk_common.skc_bind_node 388 #define sk_prot __sk_common.skc_prot 389 #define sk_net __sk_common.skc_net 390 #define sk_v6_daddr __sk_common.skc_v6_daddr 391 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 392 #define sk_cookie __sk_common.skc_cookie 393 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 394 #define sk_flags __sk_common.skc_flags 395 #define sk_rxhash __sk_common.skc_rxhash 396 397 /* early demux fields */ 398 struct dst_entry __rcu *sk_rx_dst; 399 int sk_rx_dst_ifindex; 400 u32 sk_rx_dst_cookie; 401 402 socket_lock_t sk_lock; 403 atomic_t sk_drops; 404 int sk_rcvlowat; 405 struct sk_buff_head sk_error_queue; 406 struct sk_buff_head sk_receive_queue; 407 /* 408 * The backlog queue is special, it is always used with 409 * the per-socket spinlock held and requires low latency 410 * access. Therefore we special case it's implementation. 411 * Note : rmem_alloc is in this structure to fill a hole 412 * on 64bit arches, not because its logically part of 413 * backlog. 414 */ 415 struct { 416 atomic_t rmem_alloc; 417 int len; 418 struct sk_buff *head; 419 struct sk_buff *tail; 420 } sk_backlog; 421 422 #define sk_rmem_alloc sk_backlog.rmem_alloc 423 424 int sk_forward_alloc; 425 u32 sk_reserved_mem; 426 #ifdef CONFIG_NET_RX_BUSY_POLL 427 unsigned int sk_ll_usec; 428 /* ===== mostly read cache line ===== */ 429 unsigned int sk_napi_id; 430 #endif 431 int sk_rcvbuf; 432 int sk_disconnects; 433 434 struct sk_filter __rcu *sk_filter; 435 union { 436 struct socket_wq __rcu *sk_wq; 437 /* private: */ 438 struct socket_wq *sk_wq_raw; 439 /* public: */ 440 }; 441 #ifdef CONFIG_XFRM 442 struct xfrm_policy __rcu *sk_policy[2]; 443 #endif 444 445 struct dst_entry __rcu *sk_dst_cache; 446 atomic_t sk_omem_alloc; 447 int sk_sndbuf; 448 449 /* ===== cache line for TX ===== */ 450 int sk_wmem_queued; 451 refcount_t sk_wmem_alloc; 452 unsigned long sk_tsq_flags; 453 union { 454 struct sk_buff *sk_send_head; 455 struct rb_root tcp_rtx_queue; 456 }; 457 struct sk_buff_head sk_write_queue; 458 __s32 sk_peek_off; 459 int sk_write_pending; 460 __u32 sk_dst_pending_confirm; 461 u32 sk_pacing_status; /* see enum sk_pacing */ 462 long sk_sndtimeo; 463 struct timer_list sk_timer; 464 __u32 sk_priority; 465 __u32 sk_mark; 466 unsigned long sk_pacing_rate; /* bytes per second */ 467 unsigned long sk_max_pacing_rate; 468 struct page_frag sk_frag; 469 netdev_features_t sk_route_caps; 470 int sk_gso_type; 471 unsigned int sk_gso_max_size; 472 gfp_t sk_allocation; 473 __u32 sk_txhash; 474 475 /* 476 * Because of non atomicity rules, all 477 * changes are protected by socket lock. 478 */ 479 u8 sk_gso_disabled : 1, 480 sk_kern_sock : 1, 481 sk_no_check_tx : 1, 482 sk_no_check_rx : 1, 483 sk_userlocks : 4; 484 u8 sk_pacing_shift; 485 u16 sk_type; 486 u16 sk_protocol; 487 u16 sk_gso_max_segs; 488 unsigned long sk_lingertime; 489 struct proto *sk_prot_creator; 490 rwlock_t sk_callback_lock; 491 int sk_err, 492 sk_err_soft; 493 u32 sk_ack_backlog; 494 u32 sk_max_ack_backlog; 495 kuid_t sk_uid; 496 u8 sk_txrehash; 497 #ifdef CONFIG_NET_RX_BUSY_POLL 498 u8 sk_prefer_busy_poll; 499 u16 sk_busy_poll_budget; 500 #endif 501 spinlock_t sk_peer_lock; 502 int sk_bind_phc; 503 struct pid *sk_peer_pid; 504 const struct cred *sk_peer_cred; 505 506 long sk_rcvtimeo; 507 ktime_t sk_stamp; 508 #if BITS_PER_LONG==32 509 seqlock_t sk_stamp_seq; 510 #endif 511 atomic_t sk_tskey; 512 atomic_t sk_zckey; 513 u32 sk_tsflags; 514 u8 sk_shutdown; 515 516 u8 sk_clockid; 517 u8 sk_txtime_deadline_mode : 1, 518 sk_txtime_report_errors : 1, 519 sk_txtime_unused : 6; 520 bool sk_use_task_frag; 521 522 struct socket *sk_socket; 523 void *sk_user_data; 524 #ifdef CONFIG_SECURITY 525 void *sk_security; 526 #endif 527 struct sock_cgroup_data sk_cgrp_data; 528 struct mem_cgroup *sk_memcg; 529 void (*sk_state_change)(struct sock *sk); 530 void (*sk_data_ready)(struct sock *sk); 531 void (*sk_write_space)(struct sock *sk); 532 void (*sk_error_report)(struct sock *sk); 533 int (*sk_backlog_rcv)(struct sock *sk, 534 struct sk_buff *skb); 535 #ifdef CONFIG_SOCK_VALIDATE_XMIT 536 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 537 struct net_device *dev, 538 struct sk_buff *skb); 539 #endif 540 void (*sk_destruct)(struct sock *sk); 541 struct sock_reuseport __rcu *sk_reuseport_cb; 542 #ifdef CONFIG_BPF_SYSCALL 543 struct bpf_local_storage __rcu *sk_bpf_storage; 544 #endif 545 struct rcu_head sk_rcu; 546 netns_tracker ns_tracker; 547 struct hlist_node sk_bind2_node; 548 }; 549 550 enum sk_pacing { 551 SK_PACING_NONE = 0, 552 SK_PACING_NEEDED = 1, 553 SK_PACING_FQ = 2, 554 }; 555 556 /* flag bits in sk_user_data 557 * 558 * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might 559 * not be suitable for copying when cloning the socket. For instance, 560 * it can point to a reference counted object. sk_user_data bottom 561 * bit is set if pointer must not be copied. 562 * 563 * - SK_USER_DATA_BPF: Mark whether sk_user_data field is 564 * managed/owned by a BPF reuseport array. This bit should be set 565 * when sk_user_data's sk is added to the bpf's reuseport_array. 566 * 567 * - SK_USER_DATA_PSOCK: Mark whether pointer stored in 568 * sk_user_data points to psock type. This bit should be set 569 * when sk_user_data is assigned to a psock object. 570 */ 571 #define SK_USER_DATA_NOCOPY 1UL 572 #define SK_USER_DATA_BPF 2UL 573 #define SK_USER_DATA_PSOCK 4UL 574 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\ 575 SK_USER_DATA_PSOCK) 576 577 /** 578 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied 579 * @sk: socket 580 */ 581 static inline bool sk_user_data_is_nocopy(const struct sock *sk) 582 { 583 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); 584 } 585 586 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 587 588 /** 589 * __locked_read_sk_user_data_with_flags - return the pointer 590 * only if argument flags all has been set in sk_user_data. Otherwise 591 * return NULL 592 * 593 * @sk: socket 594 * @flags: flag bits 595 * 596 * The caller must be holding sk->sk_callback_lock. 597 */ 598 static inline void * 599 __locked_read_sk_user_data_with_flags(const struct sock *sk, 600 uintptr_t flags) 601 { 602 uintptr_t sk_user_data = 603 (uintptr_t)rcu_dereference_check(__sk_user_data(sk), 604 lockdep_is_held(&sk->sk_callback_lock)); 605 606 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 607 608 if ((sk_user_data & flags) == flags) 609 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 610 return NULL; 611 } 612 613 /** 614 * __rcu_dereference_sk_user_data_with_flags - return the pointer 615 * only if argument flags all has been set in sk_user_data. Otherwise 616 * return NULL 617 * 618 * @sk: socket 619 * @flags: flag bits 620 */ 621 static inline void * 622 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk, 623 uintptr_t flags) 624 { 625 uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk)); 626 627 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 628 629 if ((sk_user_data & flags) == flags) 630 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 631 return NULL; 632 } 633 634 #define rcu_dereference_sk_user_data(sk) \ 635 __rcu_dereference_sk_user_data_with_flags(sk, 0) 636 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \ 637 ({ \ 638 uintptr_t __tmp1 = (uintptr_t)(ptr), \ 639 __tmp2 = (uintptr_t)(flags); \ 640 WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \ 641 WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \ 642 rcu_assign_pointer(__sk_user_data((sk)), \ 643 __tmp1 | __tmp2); \ 644 }) 645 #define rcu_assign_sk_user_data(sk, ptr) \ 646 __rcu_assign_sk_user_data_with_flags(sk, ptr, 0) 647 648 static inline 649 struct net *sock_net(const struct sock *sk) 650 { 651 return read_pnet(&sk->sk_net); 652 } 653 654 static inline 655 void sock_net_set(struct sock *sk, struct net *net) 656 { 657 write_pnet(&sk->sk_net, net); 658 } 659 660 /* 661 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 662 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 663 * on a socket means that the socket will reuse everybody else's port 664 * without looking at the other's sk_reuse value. 665 */ 666 667 #define SK_NO_REUSE 0 668 #define SK_CAN_REUSE 1 669 #define SK_FORCE_REUSE 2 670 671 int sk_set_peek_off(struct sock *sk, int val); 672 673 static inline int sk_peek_offset(const struct sock *sk, int flags) 674 { 675 if (unlikely(flags & MSG_PEEK)) { 676 return READ_ONCE(sk->sk_peek_off); 677 } 678 679 return 0; 680 } 681 682 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 683 { 684 s32 off = READ_ONCE(sk->sk_peek_off); 685 686 if (unlikely(off >= 0)) { 687 off = max_t(s32, off - val, 0); 688 WRITE_ONCE(sk->sk_peek_off, off); 689 } 690 } 691 692 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 693 { 694 sk_peek_offset_bwd(sk, -val); 695 } 696 697 /* 698 * Hashed lists helper routines 699 */ 700 static inline struct sock *sk_entry(const struct hlist_node *node) 701 { 702 return hlist_entry(node, struct sock, sk_node); 703 } 704 705 static inline struct sock *__sk_head(const struct hlist_head *head) 706 { 707 return hlist_entry(head->first, struct sock, sk_node); 708 } 709 710 static inline struct sock *sk_head(const struct hlist_head *head) 711 { 712 return hlist_empty(head) ? NULL : __sk_head(head); 713 } 714 715 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 716 { 717 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 718 } 719 720 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 721 { 722 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 723 } 724 725 static inline struct sock *sk_next(const struct sock *sk) 726 { 727 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 728 } 729 730 static inline struct sock *sk_nulls_next(const struct sock *sk) 731 { 732 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 733 hlist_nulls_entry(sk->sk_nulls_node.next, 734 struct sock, sk_nulls_node) : 735 NULL; 736 } 737 738 static inline bool sk_unhashed(const struct sock *sk) 739 { 740 return hlist_unhashed(&sk->sk_node); 741 } 742 743 static inline bool sk_hashed(const struct sock *sk) 744 { 745 return !sk_unhashed(sk); 746 } 747 748 static inline void sk_node_init(struct hlist_node *node) 749 { 750 node->pprev = NULL; 751 } 752 753 static inline void __sk_del_node(struct sock *sk) 754 { 755 __hlist_del(&sk->sk_node); 756 } 757 758 /* NB: equivalent to hlist_del_init_rcu */ 759 static inline bool __sk_del_node_init(struct sock *sk) 760 { 761 if (sk_hashed(sk)) { 762 __sk_del_node(sk); 763 sk_node_init(&sk->sk_node); 764 return true; 765 } 766 return false; 767 } 768 769 /* Grab socket reference count. This operation is valid only 770 when sk is ALREADY grabbed f.e. it is found in hash table 771 or a list and the lookup is made under lock preventing hash table 772 modifications. 773 */ 774 775 static __always_inline void sock_hold(struct sock *sk) 776 { 777 refcount_inc(&sk->sk_refcnt); 778 } 779 780 /* Ungrab socket in the context, which assumes that socket refcnt 781 cannot hit zero, f.e. it is true in context of any socketcall. 782 */ 783 static __always_inline void __sock_put(struct sock *sk) 784 { 785 refcount_dec(&sk->sk_refcnt); 786 } 787 788 static inline bool sk_del_node_init(struct sock *sk) 789 { 790 bool rc = __sk_del_node_init(sk); 791 792 if (rc) { 793 /* paranoid for a while -acme */ 794 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 795 __sock_put(sk); 796 } 797 return rc; 798 } 799 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 800 801 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 802 { 803 if (sk_hashed(sk)) { 804 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 805 return true; 806 } 807 return false; 808 } 809 810 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 811 { 812 bool rc = __sk_nulls_del_node_init_rcu(sk); 813 814 if (rc) { 815 /* paranoid for a while -acme */ 816 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 817 __sock_put(sk); 818 } 819 return rc; 820 } 821 822 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 823 { 824 hlist_add_head(&sk->sk_node, list); 825 } 826 827 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 828 { 829 sock_hold(sk); 830 __sk_add_node(sk, list); 831 } 832 833 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 834 { 835 sock_hold(sk); 836 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 837 sk->sk_family == AF_INET6) 838 hlist_add_tail_rcu(&sk->sk_node, list); 839 else 840 hlist_add_head_rcu(&sk->sk_node, list); 841 } 842 843 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 844 { 845 sock_hold(sk); 846 hlist_add_tail_rcu(&sk->sk_node, list); 847 } 848 849 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 850 { 851 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 852 } 853 854 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 855 { 856 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 857 } 858 859 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 860 { 861 sock_hold(sk); 862 __sk_nulls_add_node_rcu(sk, list); 863 } 864 865 static inline void __sk_del_bind_node(struct sock *sk) 866 { 867 __hlist_del(&sk->sk_bind_node); 868 } 869 870 static inline void sk_add_bind_node(struct sock *sk, 871 struct hlist_head *list) 872 { 873 hlist_add_head(&sk->sk_bind_node, list); 874 } 875 876 static inline void __sk_del_bind2_node(struct sock *sk) 877 { 878 __hlist_del(&sk->sk_bind2_node); 879 } 880 881 static inline void sk_add_bind2_node(struct sock *sk, struct hlist_head *list) 882 { 883 hlist_add_head(&sk->sk_bind2_node, list); 884 } 885 886 #define sk_for_each(__sk, list) \ 887 hlist_for_each_entry(__sk, list, sk_node) 888 #define sk_for_each_rcu(__sk, list) \ 889 hlist_for_each_entry_rcu(__sk, list, sk_node) 890 #define sk_nulls_for_each(__sk, node, list) \ 891 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 892 #define sk_nulls_for_each_rcu(__sk, node, list) \ 893 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 894 #define sk_for_each_from(__sk) \ 895 hlist_for_each_entry_from(__sk, sk_node) 896 #define sk_nulls_for_each_from(__sk, node) \ 897 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 898 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 899 #define sk_for_each_safe(__sk, tmp, list) \ 900 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 901 #define sk_for_each_bound(__sk, list) \ 902 hlist_for_each_entry(__sk, list, sk_bind_node) 903 #define sk_for_each_bound_bhash2(__sk, list) \ 904 hlist_for_each_entry(__sk, list, sk_bind2_node) 905 906 /** 907 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 908 * @tpos: the type * to use as a loop cursor. 909 * @pos: the &struct hlist_node to use as a loop cursor. 910 * @head: the head for your list. 911 * @offset: offset of hlist_node within the struct. 912 * 913 */ 914 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 915 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 916 pos != NULL && \ 917 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 918 pos = rcu_dereference(hlist_next_rcu(pos))) 919 920 static inline struct user_namespace *sk_user_ns(const struct sock *sk) 921 { 922 /* Careful only use this in a context where these parameters 923 * can not change and must all be valid, such as recvmsg from 924 * userspace. 925 */ 926 return sk->sk_socket->file->f_cred->user_ns; 927 } 928 929 /* Sock flags */ 930 enum sock_flags { 931 SOCK_DEAD, 932 SOCK_DONE, 933 SOCK_URGINLINE, 934 SOCK_KEEPOPEN, 935 SOCK_LINGER, 936 SOCK_DESTROY, 937 SOCK_BROADCAST, 938 SOCK_TIMESTAMP, 939 SOCK_ZAPPED, 940 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 941 SOCK_DBG, /* %SO_DEBUG setting */ 942 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 943 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 944 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 945 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 946 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 947 SOCK_FASYNC, /* fasync() active */ 948 SOCK_RXQ_OVFL, 949 SOCK_ZEROCOPY, /* buffers from userspace */ 950 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 951 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 952 * Will use last 4 bytes of packet sent from 953 * user-space instead. 954 */ 955 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 956 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 957 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 958 SOCK_TXTIME, 959 SOCK_XDP, /* XDP is attached */ 960 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 961 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */ 962 }; 963 964 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 965 966 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk) 967 { 968 nsk->sk_flags = osk->sk_flags; 969 } 970 971 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 972 { 973 __set_bit(flag, &sk->sk_flags); 974 } 975 976 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 977 { 978 __clear_bit(flag, &sk->sk_flags); 979 } 980 981 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 982 int valbool) 983 { 984 if (valbool) 985 sock_set_flag(sk, bit); 986 else 987 sock_reset_flag(sk, bit); 988 } 989 990 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 991 { 992 return test_bit(flag, &sk->sk_flags); 993 } 994 995 #ifdef CONFIG_NET 996 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 997 static inline int sk_memalloc_socks(void) 998 { 999 return static_branch_unlikely(&memalloc_socks_key); 1000 } 1001 1002 void __receive_sock(struct file *file); 1003 #else 1004 1005 static inline int sk_memalloc_socks(void) 1006 { 1007 return 0; 1008 } 1009 1010 static inline void __receive_sock(struct file *file) 1011 { } 1012 #endif 1013 1014 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 1015 { 1016 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 1017 } 1018 1019 static inline void sk_acceptq_removed(struct sock *sk) 1020 { 1021 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 1022 } 1023 1024 static inline void sk_acceptq_added(struct sock *sk) 1025 { 1026 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 1027 } 1028 1029 /* Note: If you think the test should be: 1030 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 1031 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 1032 */ 1033 static inline bool sk_acceptq_is_full(const struct sock *sk) 1034 { 1035 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 1036 } 1037 1038 /* 1039 * Compute minimal free write space needed to queue new packets. 1040 */ 1041 static inline int sk_stream_min_wspace(const struct sock *sk) 1042 { 1043 return READ_ONCE(sk->sk_wmem_queued) >> 1; 1044 } 1045 1046 static inline int sk_stream_wspace(const struct sock *sk) 1047 { 1048 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 1049 } 1050 1051 static inline void sk_wmem_queued_add(struct sock *sk, int val) 1052 { 1053 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 1054 } 1055 1056 static inline void sk_forward_alloc_add(struct sock *sk, int val) 1057 { 1058 /* Paired with lockless reads of sk->sk_forward_alloc */ 1059 WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val); 1060 } 1061 1062 void sk_stream_write_space(struct sock *sk); 1063 1064 /* OOB backlog add */ 1065 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 1066 { 1067 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 1068 skb_dst_force(skb); 1069 1070 if (!sk->sk_backlog.tail) 1071 WRITE_ONCE(sk->sk_backlog.head, skb); 1072 else 1073 sk->sk_backlog.tail->next = skb; 1074 1075 WRITE_ONCE(sk->sk_backlog.tail, skb); 1076 skb->next = NULL; 1077 } 1078 1079 /* 1080 * Take into account size of receive queue and backlog queue 1081 * Do not take into account this skb truesize, 1082 * to allow even a single big packet to come. 1083 */ 1084 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 1085 { 1086 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 1087 1088 return qsize > limit; 1089 } 1090 1091 /* The per-socket spinlock must be held here. */ 1092 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 1093 unsigned int limit) 1094 { 1095 if (sk_rcvqueues_full(sk, limit)) 1096 return -ENOBUFS; 1097 1098 /* 1099 * If the skb was allocated from pfmemalloc reserves, only 1100 * allow SOCK_MEMALLOC sockets to use it as this socket is 1101 * helping free memory 1102 */ 1103 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1104 return -ENOMEM; 1105 1106 __sk_add_backlog(sk, skb); 1107 sk->sk_backlog.len += skb->truesize; 1108 return 0; 1109 } 1110 1111 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1112 1113 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)); 1114 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)); 1115 1116 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1117 { 1118 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1119 return __sk_backlog_rcv(sk, skb); 1120 1121 return INDIRECT_CALL_INET(sk->sk_backlog_rcv, 1122 tcp_v6_do_rcv, 1123 tcp_v4_do_rcv, 1124 sk, skb); 1125 } 1126 1127 static inline void sk_incoming_cpu_update(struct sock *sk) 1128 { 1129 int cpu = raw_smp_processor_id(); 1130 1131 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1132 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1133 } 1134 1135 static inline void sock_rps_record_flow_hash(__u32 hash) 1136 { 1137 #ifdef CONFIG_RPS 1138 struct rps_sock_flow_table *sock_flow_table; 1139 1140 rcu_read_lock(); 1141 sock_flow_table = rcu_dereference(rps_sock_flow_table); 1142 rps_record_sock_flow(sock_flow_table, hash); 1143 rcu_read_unlock(); 1144 #endif 1145 } 1146 1147 static inline void sock_rps_record_flow(const struct sock *sk) 1148 { 1149 #ifdef CONFIG_RPS 1150 if (static_branch_unlikely(&rfs_needed)) { 1151 /* Reading sk->sk_rxhash might incur an expensive cache line 1152 * miss. 1153 * 1154 * TCP_ESTABLISHED does cover almost all states where RFS 1155 * might be useful, and is cheaper [1] than testing : 1156 * IPv4: inet_sk(sk)->inet_daddr 1157 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 1158 * OR an additional socket flag 1159 * [1] : sk_state and sk_prot are in the same cache line. 1160 */ 1161 if (sk->sk_state == TCP_ESTABLISHED) { 1162 /* This READ_ONCE() is paired with the WRITE_ONCE() 1163 * from sock_rps_save_rxhash() and sock_rps_reset_rxhash(). 1164 */ 1165 sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash)); 1166 } 1167 } 1168 #endif 1169 } 1170 1171 static inline void sock_rps_save_rxhash(struct sock *sk, 1172 const struct sk_buff *skb) 1173 { 1174 #ifdef CONFIG_RPS 1175 /* The following WRITE_ONCE() is paired with the READ_ONCE() 1176 * here, and another one in sock_rps_record_flow(). 1177 */ 1178 if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash)) 1179 WRITE_ONCE(sk->sk_rxhash, skb->hash); 1180 #endif 1181 } 1182 1183 static inline void sock_rps_reset_rxhash(struct sock *sk) 1184 { 1185 #ifdef CONFIG_RPS 1186 /* Paired with READ_ONCE() in sock_rps_record_flow() */ 1187 WRITE_ONCE(sk->sk_rxhash, 0); 1188 #endif 1189 } 1190 1191 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1192 ({ int __rc, __dis = __sk->sk_disconnects; \ 1193 release_sock(__sk); \ 1194 __rc = __condition; \ 1195 if (!__rc) { \ 1196 *(__timeo) = wait_woken(__wait, \ 1197 TASK_INTERRUPTIBLE, \ 1198 *(__timeo)); \ 1199 } \ 1200 sched_annotate_sleep(); \ 1201 lock_sock(__sk); \ 1202 __rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \ 1203 __rc; \ 1204 }) 1205 1206 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1207 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1208 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1209 int sk_stream_error(struct sock *sk, int flags, int err); 1210 void sk_stream_kill_queues(struct sock *sk); 1211 void sk_set_memalloc(struct sock *sk); 1212 void sk_clear_memalloc(struct sock *sk); 1213 1214 void __sk_flush_backlog(struct sock *sk); 1215 1216 static inline bool sk_flush_backlog(struct sock *sk) 1217 { 1218 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1219 __sk_flush_backlog(sk); 1220 return true; 1221 } 1222 return false; 1223 } 1224 1225 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1226 1227 struct request_sock_ops; 1228 struct timewait_sock_ops; 1229 struct inet_hashinfo; 1230 struct raw_hashinfo; 1231 struct smc_hashinfo; 1232 struct module; 1233 struct sk_psock; 1234 1235 /* 1236 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1237 * un-modified. Special care is taken when initializing object to zero. 1238 */ 1239 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1240 { 1241 if (offsetof(struct sock, sk_node.next) != 0) 1242 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1243 memset(&sk->sk_node.pprev, 0, 1244 size - offsetof(struct sock, sk_node.pprev)); 1245 } 1246 1247 /* Networking protocol blocks we attach to sockets. 1248 * socket layer -> transport layer interface 1249 */ 1250 struct proto { 1251 void (*close)(struct sock *sk, 1252 long timeout); 1253 int (*pre_connect)(struct sock *sk, 1254 struct sockaddr *uaddr, 1255 int addr_len); 1256 int (*connect)(struct sock *sk, 1257 struct sockaddr *uaddr, 1258 int addr_len); 1259 int (*disconnect)(struct sock *sk, int flags); 1260 1261 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1262 bool kern); 1263 1264 int (*ioctl)(struct sock *sk, int cmd, 1265 int *karg); 1266 int (*init)(struct sock *sk); 1267 void (*destroy)(struct sock *sk); 1268 void (*shutdown)(struct sock *sk, int how); 1269 int (*setsockopt)(struct sock *sk, int level, 1270 int optname, sockptr_t optval, 1271 unsigned int optlen); 1272 int (*getsockopt)(struct sock *sk, int level, 1273 int optname, char __user *optval, 1274 int __user *option); 1275 void (*keepalive)(struct sock *sk, int valbool); 1276 #ifdef CONFIG_COMPAT 1277 int (*compat_ioctl)(struct sock *sk, 1278 unsigned int cmd, unsigned long arg); 1279 #endif 1280 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1281 size_t len); 1282 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1283 size_t len, int flags, int *addr_len); 1284 void (*splice_eof)(struct socket *sock); 1285 int (*bind)(struct sock *sk, 1286 struct sockaddr *addr, int addr_len); 1287 int (*bind_add)(struct sock *sk, 1288 struct sockaddr *addr, int addr_len); 1289 1290 int (*backlog_rcv) (struct sock *sk, 1291 struct sk_buff *skb); 1292 bool (*bpf_bypass_getsockopt)(int level, 1293 int optname); 1294 1295 void (*release_cb)(struct sock *sk); 1296 1297 /* Keeping track of sk's, looking them up, and port selection methods. */ 1298 int (*hash)(struct sock *sk); 1299 void (*unhash)(struct sock *sk); 1300 void (*rehash)(struct sock *sk); 1301 int (*get_port)(struct sock *sk, unsigned short snum); 1302 void (*put_port)(struct sock *sk); 1303 #ifdef CONFIG_BPF_SYSCALL 1304 int (*psock_update_sk_prot)(struct sock *sk, 1305 struct sk_psock *psock, 1306 bool restore); 1307 #endif 1308 1309 /* Keeping track of sockets in use */ 1310 #ifdef CONFIG_PROC_FS 1311 unsigned int inuse_idx; 1312 #endif 1313 1314 #if IS_ENABLED(CONFIG_MPTCP) 1315 int (*forward_alloc_get)(const struct sock *sk); 1316 #endif 1317 1318 bool (*stream_memory_free)(const struct sock *sk, int wake); 1319 bool (*sock_is_readable)(struct sock *sk); 1320 /* Memory pressure */ 1321 void (*enter_memory_pressure)(struct sock *sk); 1322 void (*leave_memory_pressure)(struct sock *sk); 1323 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1324 int __percpu *per_cpu_fw_alloc; 1325 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1326 1327 /* 1328 * Pressure flag: try to collapse. 1329 * Technical note: it is used by multiple contexts non atomically. 1330 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes. 1331 * All the __sk_mem_schedule() is of this nature: accounting 1332 * is strict, actions are advisory and have some latency. 1333 */ 1334 unsigned long *memory_pressure; 1335 long *sysctl_mem; 1336 1337 int *sysctl_wmem; 1338 int *sysctl_rmem; 1339 u32 sysctl_wmem_offset; 1340 u32 sysctl_rmem_offset; 1341 1342 int max_header; 1343 bool no_autobind; 1344 1345 struct kmem_cache *slab; 1346 unsigned int obj_size; 1347 unsigned int ipv6_pinfo_offset; 1348 slab_flags_t slab_flags; 1349 unsigned int useroffset; /* Usercopy region offset */ 1350 unsigned int usersize; /* Usercopy region size */ 1351 1352 unsigned int __percpu *orphan_count; 1353 1354 struct request_sock_ops *rsk_prot; 1355 struct timewait_sock_ops *twsk_prot; 1356 1357 union { 1358 struct inet_hashinfo *hashinfo; 1359 struct udp_table *udp_table; 1360 struct raw_hashinfo *raw_hash; 1361 struct smc_hashinfo *smc_hash; 1362 } h; 1363 1364 struct module *owner; 1365 1366 char name[32]; 1367 1368 struct list_head node; 1369 int (*diag_destroy)(struct sock *sk, int err); 1370 } __randomize_layout; 1371 1372 int proto_register(struct proto *prot, int alloc_slab); 1373 void proto_unregister(struct proto *prot); 1374 int sock_load_diag_module(int family, int protocol); 1375 1376 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1377 1378 static inline int sk_forward_alloc_get(const struct sock *sk) 1379 { 1380 #if IS_ENABLED(CONFIG_MPTCP) 1381 if (sk->sk_prot->forward_alloc_get) 1382 return sk->sk_prot->forward_alloc_get(sk); 1383 #endif 1384 return READ_ONCE(sk->sk_forward_alloc); 1385 } 1386 1387 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1388 { 1389 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1390 return false; 1391 1392 return sk->sk_prot->stream_memory_free ? 1393 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free, 1394 tcp_stream_memory_free, sk, wake) : true; 1395 } 1396 1397 static inline bool sk_stream_memory_free(const struct sock *sk) 1398 { 1399 return __sk_stream_memory_free(sk, 0); 1400 } 1401 1402 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1403 { 1404 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1405 __sk_stream_memory_free(sk, wake); 1406 } 1407 1408 static inline bool sk_stream_is_writeable(const struct sock *sk) 1409 { 1410 return __sk_stream_is_writeable(sk, 0); 1411 } 1412 1413 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1414 struct cgroup *ancestor) 1415 { 1416 #ifdef CONFIG_SOCK_CGROUP_DATA 1417 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1418 ancestor); 1419 #else 1420 return -ENOTSUPP; 1421 #endif 1422 } 1423 1424 static inline bool sk_has_memory_pressure(const struct sock *sk) 1425 { 1426 return sk->sk_prot->memory_pressure != NULL; 1427 } 1428 1429 static inline bool sk_under_global_memory_pressure(const struct sock *sk) 1430 { 1431 return sk->sk_prot->memory_pressure && 1432 !!READ_ONCE(*sk->sk_prot->memory_pressure); 1433 } 1434 1435 static inline bool sk_under_memory_pressure(const struct sock *sk) 1436 { 1437 if (!sk->sk_prot->memory_pressure) 1438 return false; 1439 1440 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1441 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1442 return true; 1443 1444 return !!READ_ONCE(*sk->sk_prot->memory_pressure); 1445 } 1446 1447 static inline long 1448 proto_memory_allocated(const struct proto *prot) 1449 { 1450 return max(0L, atomic_long_read(prot->memory_allocated)); 1451 } 1452 1453 static inline long 1454 sk_memory_allocated(const struct sock *sk) 1455 { 1456 return proto_memory_allocated(sk->sk_prot); 1457 } 1458 1459 /* 1 MB per cpu, in page units */ 1460 #define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT)) 1461 1462 static inline void 1463 sk_memory_allocated_add(struct sock *sk, int amt) 1464 { 1465 int local_reserve; 1466 1467 preempt_disable(); 1468 local_reserve = __this_cpu_add_return(*sk->sk_prot->per_cpu_fw_alloc, amt); 1469 if (local_reserve >= SK_MEMORY_PCPU_RESERVE) { 1470 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve); 1471 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated); 1472 } 1473 preempt_enable(); 1474 } 1475 1476 static inline void 1477 sk_memory_allocated_sub(struct sock *sk, int amt) 1478 { 1479 int local_reserve; 1480 1481 preempt_disable(); 1482 local_reserve = __this_cpu_sub_return(*sk->sk_prot->per_cpu_fw_alloc, amt); 1483 if (local_reserve <= -SK_MEMORY_PCPU_RESERVE) { 1484 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve); 1485 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated); 1486 } 1487 preempt_enable(); 1488 } 1489 1490 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1491 1492 static inline void sk_sockets_allocated_dec(struct sock *sk) 1493 { 1494 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1495 SK_ALLOC_PERCPU_COUNTER_BATCH); 1496 } 1497 1498 static inline void sk_sockets_allocated_inc(struct sock *sk) 1499 { 1500 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1501 SK_ALLOC_PERCPU_COUNTER_BATCH); 1502 } 1503 1504 static inline u64 1505 sk_sockets_allocated_read_positive(struct sock *sk) 1506 { 1507 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1508 } 1509 1510 static inline int 1511 proto_sockets_allocated_sum_positive(struct proto *prot) 1512 { 1513 return percpu_counter_sum_positive(prot->sockets_allocated); 1514 } 1515 1516 static inline bool 1517 proto_memory_pressure(struct proto *prot) 1518 { 1519 if (!prot->memory_pressure) 1520 return false; 1521 return !!READ_ONCE(*prot->memory_pressure); 1522 } 1523 1524 1525 #ifdef CONFIG_PROC_FS 1526 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 1527 struct prot_inuse { 1528 int all; 1529 int val[PROTO_INUSE_NR]; 1530 }; 1531 1532 static inline void sock_prot_inuse_add(const struct net *net, 1533 const struct proto *prot, int val) 1534 { 1535 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 1536 } 1537 1538 static inline void sock_inuse_add(const struct net *net, int val) 1539 { 1540 this_cpu_add(net->core.prot_inuse->all, val); 1541 } 1542 1543 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1544 int sock_inuse_get(struct net *net); 1545 #else 1546 static inline void sock_prot_inuse_add(const struct net *net, 1547 const struct proto *prot, int val) 1548 { 1549 } 1550 1551 static inline void sock_inuse_add(const struct net *net, int val) 1552 { 1553 } 1554 #endif 1555 1556 1557 /* With per-bucket locks this operation is not-atomic, so that 1558 * this version is not worse. 1559 */ 1560 static inline int __sk_prot_rehash(struct sock *sk) 1561 { 1562 sk->sk_prot->unhash(sk); 1563 return sk->sk_prot->hash(sk); 1564 } 1565 1566 /* About 10 seconds */ 1567 #define SOCK_DESTROY_TIME (10*HZ) 1568 1569 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1570 #define PROT_SOCK 1024 1571 1572 #define SHUTDOWN_MASK 3 1573 #define RCV_SHUTDOWN 1 1574 #define SEND_SHUTDOWN 2 1575 1576 #define SOCK_BINDADDR_LOCK 4 1577 #define SOCK_BINDPORT_LOCK 8 1578 1579 struct socket_alloc { 1580 struct socket socket; 1581 struct inode vfs_inode; 1582 }; 1583 1584 static inline struct socket *SOCKET_I(struct inode *inode) 1585 { 1586 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1587 } 1588 1589 static inline struct inode *SOCK_INODE(struct socket *socket) 1590 { 1591 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1592 } 1593 1594 /* 1595 * Functions for memory accounting 1596 */ 1597 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1598 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1599 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1600 void __sk_mem_reclaim(struct sock *sk, int amount); 1601 1602 #define SK_MEM_SEND 0 1603 #define SK_MEM_RECV 1 1604 1605 /* sysctl_mem values are in pages */ 1606 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1607 { 1608 return READ_ONCE(sk->sk_prot->sysctl_mem[index]); 1609 } 1610 1611 static inline int sk_mem_pages(int amt) 1612 { 1613 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT; 1614 } 1615 1616 static inline bool sk_has_account(struct sock *sk) 1617 { 1618 /* return true if protocol supports memory accounting */ 1619 return !!sk->sk_prot->memory_allocated; 1620 } 1621 1622 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1623 { 1624 int delta; 1625 1626 if (!sk_has_account(sk)) 1627 return true; 1628 delta = size - sk->sk_forward_alloc; 1629 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND); 1630 } 1631 1632 static inline bool 1633 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1634 { 1635 int delta; 1636 1637 if (!sk_has_account(sk)) 1638 return true; 1639 delta = size - sk->sk_forward_alloc; 1640 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) || 1641 skb_pfmemalloc(skb); 1642 } 1643 1644 static inline int sk_unused_reserved_mem(const struct sock *sk) 1645 { 1646 int unused_mem; 1647 1648 if (likely(!sk->sk_reserved_mem)) 1649 return 0; 1650 1651 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued - 1652 atomic_read(&sk->sk_rmem_alloc); 1653 1654 return unused_mem > 0 ? unused_mem : 0; 1655 } 1656 1657 static inline void sk_mem_reclaim(struct sock *sk) 1658 { 1659 int reclaimable; 1660 1661 if (!sk_has_account(sk)) 1662 return; 1663 1664 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk); 1665 1666 if (reclaimable >= (int)PAGE_SIZE) 1667 __sk_mem_reclaim(sk, reclaimable); 1668 } 1669 1670 static inline void sk_mem_reclaim_final(struct sock *sk) 1671 { 1672 sk->sk_reserved_mem = 0; 1673 sk_mem_reclaim(sk); 1674 } 1675 1676 static inline void sk_mem_charge(struct sock *sk, int size) 1677 { 1678 if (!sk_has_account(sk)) 1679 return; 1680 sk_forward_alloc_add(sk, -size); 1681 } 1682 1683 static inline void sk_mem_uncharge(struct sock *sk, int size) 1684 { 1685 if (!sk_has_account(sk)) 1686 return; 1687 sk_forward_alloc_add(sk, size); 1688 sk_mem_reclaim(sk); 1689 } 1690 1691 /* 1692 * Macro so as to not evaluate some arguments when 1693 * lockdep is not enabled. 1694 * 1695 * Mark both the sk_lock and the sk_lock.slock as a 1696 * per-address-family lock class. 1697 */ 1698 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1699 do { \ 1700 sk->sk_lock.owned = 0; \ 1701 init_waitqueue_head(&sk->sk_lock.wq); \ 1702 spin_lock_init(&(sk)->sk_lock.slock); \ 1703 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1704 sizeof((sk)->sk_lock)); \ 1705 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1706 (skey), (sname)); \ 1707 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1708 } while (0) 1709 1710 static inline bool lockdep_sock_is_held(const struct sock *sk) 1711 { 1712 return lockdep_is_held(&sk->sk_lock) || 1713 lockdep_is_held(&sk->sk_lock.slock); 1714 } 1715 1716 void lock_sock_nested(struct sock *sk, int subclass); 1717 1718 static inline void lock_sock(struct sock *sk) 1719 { 1720 lock_sock_nested(sk, 0); 1721 } 1722 1723 void __lock_sock(struct sock *sk); 1724 void __release_sock(struct sock *sk); 1725 void release_sock(struct sock *sk); 1726 1727 /* BH context may only use the following locking interface. */ 1728 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1729 #define bh_lock_sock_nested(__sk) \ 1730 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1731 SINGLE_DEPTH_NESTING) 1732 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1733 1734 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1735 1736 /** 1737 * lock_sock_fast - fast version of lock_sock 1738 * @sk: socket 1739 * 1740 * This version should be used for very small section, where process wont block 1741 * return false if fast path is taken: 1742 * 1743 * sk_lock.slock locked, owned = 0, BH disabled 1744 * 1745 * return true if slow path is taken: 1746 * 1747 * sk_lock.slock unlocked, owned = 1, BH enabled 1748 */ 1749 static inline bool lock_sock_fast(struct sock *sk) 1750 { 1751 /* The sk_lock has mutex_lock() semantics here. */ 1752 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 1753 1754 return __lock_sock_fast(sk); 1755 } 1756 1757 /* fast socket lock variant for caller already holding a [different] socket lock */ 1758 static inline bool lock_sock_fast_nested(struct sock *sk) 1759 { 1760 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_); 1761 1762 return __lock_sock_fast(sk); 1763 } 1764 1765 /** 1766 * unlock_sock_fast - complement of lock_sock_fast 1767 * @sk: socket 1768 * @slow: slow mode 1769 * 1770 * fast unlock socket for user context. 1771 * If slow mode is on, we call regular release_sock() 1772 */ 1773 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1774 __releases(&sk->sk_lock.slock) 1775 { 1776 if (slow) { 1777 release_sock(sk); 1778 __release(&sk->sk_lock.slock); 1779 } else { 1780 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1781 spin_unlock_bh(&sk->sk_lock.slock); 1782 } 1783 } 1784 1785 void sockopt_lock_sock(struct sock *sk); 1786 void sockopt_release_sock(struct sock *sk); 1787 bool sockopt_ns_capable(struct user_namespace *ns, int cap); 1788 bool sockopt_capable(int cap); 1789 1790 /* Used by processes to "lock" a socket state, so that 1791 * interrupts and bottom half handlers won't change it 1792 * from under us. It essentially blocks any incoming 1793 * packets, so that we won't get any new data or any 1794 * packets that change the state of the socket. 1795 * 1796 * While locked, BH processing will add new packets to 1797 * the backlog queue. This queue is processed by the 1798 * owner of the socket lock right before it is released. 1799 * 1800 * Since ~2.3.5 it is also exclusive sleep lock serializing 1801 * accesses from user process context. 1802 */ 1803 1804 static inline void sock_owned_by_me(const struct sock *sk) 1805 { 1806 #ifdef CONFIG_LOCKDEP 1807 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1808 #endif 1809 } 1810 1811 static inline bool sock_owned_by_user(const struct sock *sk) 1812 { 1813 sock_owned_by_me(sk); 1814 return sk->sk_lock.owned; 1815 } 1816 1817 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1818 { 1819 return sk->sk_lock.owned; 1820 } 1821 1822 static inline void sock_release_ownership(struct sock *sk) 1823 { 1824 if (sock_owned_by_user_nocheck(sk)) { 1825 sk->sk_lock.owned = 0; 1826 1827 /* The sk_lock has mutex_unlock() semantics: */ 1828 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1829 } 1830 } 1831 1832 /* no reclassification while locks are held */ 1833 static inline bool sock_allow_reclassification(const struct sock *csk) 1834 { 1835 struct sock *sk = (struct sock *)csk; 1836 1837 return !sock_owned_by_user_nocheck(sk) && 1838 !spin_is_locked(&sk->sk_lock.slock); 1839 } 1840 1841 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1842 struct proto *prot, int kern); 1843 void sk_free(struct sock *sk); 1844 void sk_destruct(struct sock *sk); 1845 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1846 void sk_free_unlock_clone(struct sock *sk); 1847 1848 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1849 gfp_t priority); 1850 void __sock_wfree(struct sk_buff *skb); 1851 void sock_wfree(struct sk_buff *skb); 1852 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1853 gfp_t priority); 1854 void skb_orphan_partial(struct sk_buff *skb); 1855 void sock_rfree(struct sk_buff *skb); 1856 void sock_efree(struct sk_buff *skb); 1857 #ifdef CONFIG_INET 1858 void sock_edemux(struct sk_buff *skb); 1859 void sock_pfree(struct sk_buff *skb); 1860 #else 1861 #define sock_edemux sock_efree 1862 #endif 1863 1864 int sk_setsockopt(struct sock *sk, int level, int optname, 1865 sockptr_t optval, unsigned int optlen); 1866 int sock_setsockopt(struct socket *sock, int level, int op, 1867 sockptr_t optval, unsigned int optlen); 1868 1869 int sk_getsockopt(struct sock *sk, int level, int optname, 1870 sockptr_t optval, sockptr_t optlen); 1871 int sock_getsockopt(struct socket *sock, int level, int op, 1872 char __user *optval, int __user *optlen); 1873 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1874 bool timeval, bool time32); 1875 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1876 unsigned long data_len, int noblock, 1877 int *errcode, int max_page_order); 1878 1879 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1880 unsigned long size, 1881 int noblock, int *errcode) 1882 { 1883 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1884 } 1885 1886 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1887 void sock_kfree_s(struct sock *sk, void *mem, int size); 1888 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1889 void sk_send_sigurg(struct sock *sk); 1890 1891 static inline void sock_replace_proto(struct sock *sk, struct proto *proto) 1892 { 1893 if (sk->sk_socket) 1894 clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1895 WRITE_ONCE(sk->sk_prot, proto); 1896 } 1897 1898 struct sockcm_cookie { 1899 u64 transmit_time; 1900 u32 mark; 1901 u32 tsflags; 1902 }; 1903 1904 static inline void sockcm_init(struct sockcm_cookie *sockc, 1905 const struct sock *sk) 1906 { 1907 *sockc = (struct sockcm_cookie) { 1908 .tsflags = READ_ONCE(sk->sk_tsflags) 1909 }; 1910 } 1911 1912 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 1913 struct sockcm_cookie *sockc); 1914 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1915 struct sockcm_cookie *sockc); 1916 1917 /* 1918 * Functions to fill in entries in struct proto_ops when a protocol 1919 * does not implement a particular function. 1920 */ 1921 int sock_no_bind(struct socket *, struct sockaddr *, int); 1922 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1923 int sock_no_socketpair(struct socket *, struct socket *); 1924 int sock_no_accept(struct socket *, struct socket *, int, bool); 1925 int sock_no_getname(struct socket *, struct sockaddr *, int); 1926 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1927 int sock_no_listen(struct socket *, int); 1928 int sock_no_shutdown(struct socket *, int); 1929 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1930 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1931 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1932 int sock_no_mmap(struct file *file, struct socket *sock, 1933 struct vm_area_struct *vma); 1934 1935 /* 1936 * Functions to fill in entries in struct proto_ops when a protocol 1937 * uses the inet style. 1938 */ 1939 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1940 char __user *optval, int __user *optlen); 1941 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1942 int flags); 1943 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1944 sockptr_t optval, unsigned int optlen); 1945 1946 void sk_common_release(struct sock *sk); 1947 1948 /* 1949 * Default socket callbacks and setup code 1950 */ 1951 1952 /* Initialise core socket variables using an explicit uid. */ 1953 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid); 1954 1955 /* Initialise core socket variables. 1956 * Assumes struct socket *sock is embedded in a struct socket_alloc. 1957 */ 1958 void sock_init_data(struct socket *sock, struct sock *sk); 1959 1960 /* 1961 * Socket reference counting postulates. 1962 * 1963 * * Each user of socket SHOULD hold a reference count. 1964 * * Each access point to socket (an hash table bucket, reference from a list, 1965 * running timer, skb in flight MUST hold a reference count. 1966 * * When reference count hits 0, it means it will never increase back. 1967 * * When reference count hits 0, it means that no references from 1968 * outside exist to this socket and current process on current CPU 1969 * is last user and may/should destroy this socket. 1970 * * sk_free is called from any context: process, BH, IRQ. When 1971 * it is called, socket has no references from outside -> sk_free 1972 * may release descendant resources allocated by the socket, but 1973 * to the time when it is called, socket is NOT referenced by any 1974 * hash tables, lists etc. 1975 * * Packets, delivered from outside (from network or from another process) 1976 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1977 * when they sit in queue. Otherwise, packets will leak to hole, when 1978 * socket is looked up by one cpu and unhasing is made by another CPU. 1979 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1980 * (leak to backlog). Packet socket does all the processing inside 1981 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1982 * use separate SMP lock, so that they are prone too. 1983 */ 1984 1985 /* Ungrab socket and destroy it, if it was the last reference. */ 1986 static inline void sock_put(struct sock *sk) 1987 { 1988 if (refcount_dec_and_test(&sk->sk_refcnt)) 1989 sk_free(sk); 1990 } 1991 /* Generic version of sock_put(), dealing with all sockets 1992 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1993 */ 1994 void sock_gen_put(struct sock *sk); 1995 1996 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1997 unsigned int trim_cap, bool refcounted); 1998 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1999 const int nested) 2000 { 2001 return __sk_receive_skb(sk, skb, nested, 1, true); 2002 } 2003 2004 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 2005 { 2006 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 2007 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 2008 return; 2009 sk->sk_tx_queue_mapping = tx_queue; 2010 } 2011 2012 #define NO_QUEUE_MAPPING USHRT_MAX 2013 2014 static inline void sk_tx_queue_clear(struct sock *sk) 2015 { 2016 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 2017 } 2018 2019 static inline int sk_tx_queue_get(const struct sock *sk) 2020 { 2021 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 2022 return sk->sk_tx_queue_mapping; 2023 2024 return -1; 2025 } 2026 2027 static inline void __sk_rx_queue_set(struct sock *sk, 2028 const struct sk_buff *skb, 2029 bool force_set) 2030 { 2031 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2032 if (skb_rx_queue_recorded(skb)) { 2033 u16 rx_queue = skb_get_rx_queue(skb); 2034 2035 if (force_set || 2036 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) 2037 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue); 2038 } 2039 #endif 2040 } 2041 2042 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 2043 { 2044 __sk_rx_queue_set(sk, skb, true); 2045 } 2046 2047 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb) 2048 { 2049 __sk_rx_queue_set(sk, skb, false); 2050 } 2051 2052 static inline void sk_rx_queue_clear(struct sock *sk) 2053 { 2054 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2055 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING); 2056 #endif 2057 } 2058 2059 static inline int sk_rx_queue_get(const struct sock *sk) 2060 { 2061 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2062 if (sk) { 2063 int res = READ_ONCE(sk->sk_rx_queue_mapping); 2064 2065 if (res != NO_QUEUE_MAPPING) 2066 return res; 2067 } 2068 #endif 2069 2070 return -1; 2071 } 2072 2073 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 2074 { 2075 sk->sk_socket = sock; 2076 } 2077 2078 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 2079 { 2080 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 2081 return &rcu_dereference_raw(sk->sk_wq)->wait; 2082 } 2083 /* Detach socket from process context. 2084 * Announce socket dead, detach it from wait queue and inode. 2085 * Note that parent inode held reference count on this struct sock, 2086 * we do not release it in this function, because protocol 2087 * probably wants some additional cleanups or even continuing 2088 * to work with this socket (TCP). 2089 */ 2090 static inline void sock_orphan(struct sock *sk) 2091 { 2092 write_lock_bh(&sk->sk_callback_lock); 2093 sock_set_flag(sk, SOCK_DEAD); 2094 sk_set_socket(sk, NULL); 2095 sk->sk_wq = NULL; 2096 write_unlock_bh(&sk->sk_callback_lock); 2097 } 2098 2099 static inline void sock_graft(struct sock *sk, struct socket *parent) 2100 { 2101 WARN_ON(parent->sk); 2102 write_lock_bh(&sk->sk_callback_lock); 2103 rcu_assign_pointer(sk->sk_wq, &parent->wq); 2104 parent->sk = sk; 2105 sk_set_socket(sk, parent); 2106 sk->sk_uid = SOCK_INODE(parent)->i_uid; 2107 security_sock_graft(sk, parent); 2108 write_unlock_bh(&sk->sk_callback_lock); 2109 } 2110 2111 kuid_t sock_i_uid(struct sock *sk); 2112 unsigned long __sock_i_ino(struct sock *sk); 2113 unsigned long sock_i_ino(struct sock *sk); 2114 2115 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 2116 { 2117 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 2118 } 2119 2120 static inline u32 net_tx_rndhash(void) 2121 { 2122 u32 v = get_random_u32(); 2123 2124 return v ?: 1; 2125 } 2126 2127 static inline void sk_set_txhash(struct sock *sk) 2128 { 2129 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */ 2130 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash()); 2131 } 2132 2133 static inline bool sk_rethink_txhash(struct sock *sk) 2134 { 2135 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) { 2136 sk_set_txhash(sk); 2137 return true; 2138 } 2139 return false; 2140 } 2141 2142 static inline struct dst_entry * 2143 __sk_dst_get(struct sock *sk) 2144 { 2145 return rcu_dereference_check(sk->sk_dst_cache, 2146 lockdep_sock_is_held(sk)); 2147 } 2148 2149 static inline struct dst_entry * 2150 sk_dst_get(struct sock *sk) 2151 { 2152 struct dst_entry *dst; 2153 2154 rcu_read_lock(); 2155 dst = rcu_dereference(sk->sk_dst_cache); 2156 if (dst && !rcuref_get(&dst->__rcuref)) 2157 dst = NULL; 2158 rcu_read_unlock(); 2159 return dst; 2160 } 2161 2162 static inline void __dst_negative_advice(struct sock *sk) 2163 { 2164 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 2165 2166 if (dst && dst->ops->negative_advice) { 2167 ndst = dst->ops->negative_advice(dst); 2168 2169 if (ndst != dst) { 2170 rcu_assign_pointer(sk->sk_dst_cache, ndst); 2171 sk_tx_queue_clear(sk); 2172 sk->sk_dst_pending_confirm = 0; 2173 } 2174 } 2175 } 2176 2177 static inline void dst_negative_advice(struct sock *sk) 2178 { 2179 sk_rethink_txhash(sk); 2180 __dst_negative_advice(sk); 2181 } 2182 2183 static inline void 2184 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 2185 { 2186 struct dst_entry *old_dst; 2187 2188 sk_tx_queue_clear(sk); 2189 sk->sk_dst_pending_confirm = 0; 2190 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 2191 lockdep_sock_is_held(sk)); 2192 rcu_assign_pointer(sk->sk_dst_cache, dst); 2193 dst_release(old_dst); 2194 } 2195 2196 static inline void 2197 sk_dst_set(struct sock *sk, struct dst_entry *dst) 2198 { 2199 struct dst_entry *old_dst; 2200 2201 sk_tx_queue_clear(sk); 2202 sk->sk_dst_pending_confirm = 0; 2203 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 2204 dst_release(old_dst); 2205 } 2206 2207 static inline void 2208 __sk_dst_reset(struct sock *sk) 2209 { 2210 __sk_dst_set(sk, NULL); 2211 } 2212 2213 static inline void 2214 sk_dst_reset(struct sock *sk) 2215 { 2216 sk_dst_set(sk, NULL); 2217 } 2218 2219 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2220 2221 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2222 2223 static inline void sk_dst_confirm(struct sock *sk) 2224 { 2225 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2226 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2227 } 2228 2229 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2230 { 2231 if (skb_get_dst_pending_confirm(skb)) { 2232 struct sock *sk = skb->sk; 2233 2234 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2235 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2236 neigh_confirm(n); 2237 } 2238 } 2239 2240 bool sk_mc_loop(struct sock *sk); 2241 2242 static inline bool sk_can_gso(const struct sock *sk) 2243 { 2244 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2245 } 2246 2247 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2248 2249 static inline void sk_gso_disable(struct sock *sk) 2250 { 2251 sk->sk_gso_disabled = 1; 2252 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2253 } 2254 2255 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2256 struct iov_iter *from, char *to, 2257 int copy, int offset) 2258 { 2259 if (skb->ip_summed == CHECKSUM_NONE) { 2260 __wsum csum = 0; 2261 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2262 return -EFAULT; 2263 skb->csum = csum_block_add(skb->csum, csum, offset); 2264 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2265 if (!copy_from_iter_full_nocache(to, copy, from)) 2266 return -EFAULT; 2267 } else if (!copy_from_iter_full(to, copy, from)) 2268 return -EFAULT; 2269 2270 return 0; 2271 } 2272 2273 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2274 struct iov_iter *from, int copy) 2275 { 2276 int err, offset = skb->len; 2277 2278 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2279 copy, offset); 2280 if (err) 2281 __skb_trim(skb, offset); 2282 2283 return err; 2284 } 2285 2286 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2287 struct sk_buff *skb, 2288 struct page *page, 2289 int off, int copy) 2290 { 2291 int err; 2292 2293 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2294 copy, skb->len); 2295 if (err) 2296 return err; 2297 2298 skb_len_add(skb, copy); 2299 sk_wmem_queued_add(sk, copy); 2300 sk_mem_charge(sk, copy); 2301 return 0; 2302 } 2303 2304 /** 2305 * sk_wmem_alloc_get - returns write allocations 2306 * @sk: socket 2307 * 2308 * Return: sk_wmem_alloc minus initial offset of one 2309 */ 2310 static inline int sk_wmem_alloc_get(const struct sock *sk) 2311 { 2312 return refcount_read(&sk->sk_wmem_alloc) - 1; 2313 } 2314 2315 /** 2316 * sk_rmem_alloc_get - returns read allocations 2317 * @sk: socket 2318 * 2319 * Return: sk_rmem_alloc 2320 */ 2321 static inline int sk_rmem_alloc_get(const struct sock *sk) 2322 { 2323 return atomic_read(&sk->sk_rmem_alloc); 2324 } 2325 2326 /** 2327 * sk_has_allocations - check if allocations are outstanding 2328 * @sk: socket 2329 * 2330 * Return: true if socket has write or read allocations 2331 */ 2332 static inline bool sk_has_allocations(const struct sock *sk) 2333 { 2334 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2335 } 2336 2337 /** 2338 * skwq_has_sleeper - check if there are any waiting processes 2339 * @wq: struct socket_wq 2340 * 2341 * Return: true if socket_wq has waiting processes 2342 * 2343 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2344 * barrier call. They were added due to the race found within the tcp code. 2345 * 2346 * Consider following tcp code paths:: 2347 * 2348 * CPU1 CPU2 2349 * sys_select receive packet 2350 * ... ... 2351 * __add_wait_queue update tp->rcv_nxt 2352 * ... ... 2353 * tp->rcv_nxt check sock_def_readable 2354 * ... { 2355 * schedule rcu_read_lock(); 2356 * wq = rcu_dereference(sk->sk_wq); 2357 * if (wq && waitqueue_active(&wq->wait)) 2358 * wake_up_interruptible(&wq->wait) 2359 * ... 2360 * } 2361 * 2362 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2363 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2364 * could then endup calling schedule and sleep forever if there are no more 2365 * data on the socket. 2366 * 2367 */ 2368 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2369 { 2370 return wq && wq_has_sleeper(&wq->wait); 2371 } 2372 2373 /** 2374 * sock_poll_wait - place memory barrier behind the poll_wait call. 2375 * @filp: file 2376 * @sock: socket to wait on 2377 * @p: poll_table 2378 * 2379 * See the comments in the wq_has_sleeper function. 2380 */ 2381 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2382 poll_table *p) 2383 { 2384 if (!poll_does_not_wait(p)) { 2385 poll_wait(filp, &sock->wq.wait, p); 2386 /* We need to be sure we are in sync with the 2387 * socket flags modification. 2388 * 2389 * This memory barrier is paired in the wq_has_sleeper. 2390 */ 2391 smp_mb(); 2392 } 2393 } 2394 2395 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2396 { 2397 /* This pairs with WRITE_ONCE() in sk_set_txhash() */ 2398 u32 txhash = READ_ONCE(sk->sk_txhash); 2399 2400 if (txhash) { 2401 skb->l4_hash = 1; 2402 skb->hash = txhash; 2403 } 2404 } 2405 2406 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2407 2408 /* 2409 * Queue a received datagram if it will fit. Stream and sequenced 2410 * protocols can't normally use this as they need to fit buffers in 2411 * and play with them. 2412 * 2413 * Inlined as it's very short and called for pretty much every 2414 * packet ever received. 2415 */ 2416 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2417 { 2418 skb_orphan(skb); 2419 skb->sk = sk; 2420 skb->destructor = sock_rfree; 2421 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2422 sk_mem_charge(sk, skb->truesize); 2423 } 2424 2425 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2426 { 2427 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2428 skb_orphan(skb); 2429 skb->destructor = sock_efree; 2430 skb->sk = sk; 2431 return true; 2432 } 2433 return false; 2434 } 2435 2436 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) 2437 { 2438 skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 2439 if (skb) { 2440 if (sk_rmem_schedule(sk, skb, skb->truesize)) { 2441 skb_set_owner_r(skb, sk); 2442 return skb; 2443 } 2444 __kfree_skb(skb); 2445 } 2446 return NULL; 2447 } 2448 2449 static inline void skb_prepare_for_gro(struct sk_buff *skb) 2450 { 2451 if (skb->destructor != sock_wfree) { 2452 skb_orphan(skb); 2453 return; 2454 } 2455 skb->slow_gro = 1; 2456 } 2457 2458 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2459 unsigned long expires); 2460 2461 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2462 2463 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2464 2465 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2466 struct sk_buff *skb, unsigned int flags, 2467 void (*destructor)(struct sock *sk, 2468 struct sk_buff *skb)); 2469 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2470 2471 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 2472 enum skb_drop_reason *reason); 2473 2474 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 2475 { 2476 return sock_queue_rcv_skb_reason(sk, skb, NULL); 2477 } 2478 2479 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2480 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2481 2482 /* 2483 * Recover an error report and clear atomically 2484 */ 2485 2486 static inline int sock_error(struct sock *sk) 2487 { 2488 int err; 2489 2490 /* Avoid an atomic operation for the common case. 2491 * This is racy since another cpu/thread can change sk_err under us. 2492 */ 2493 if (likely(data_race(!sk->sk_err))) 2494 return 0; 2495 2496 err = xchg(&sk->sk_err, 0); 2497 return -err; 2498 } 2499 2500 void sk_error_report(struct sock *sk); 2501 2502 static inline unsigned long sock_wspace(struct sock *sk) 2503 { 2504 int amt = 0; 2505 2506 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2507 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2508 if (amt < 0) 2509 amt = 0; 2510 } 2511 return amt; 2512 } 2513 2514 /* Note: 2515 * We use sk->sk_wq_raw, from contexts knowing this 2516 * pointer is not NULL and cannot disappear/change. 2517 */ 2518 static inline void sk_set_bit(int nr, struct sock *sk) 2519 { 2520 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2521 !sock_flag(sk, SOCK_FASYNC)) 2522 return; 2523 2524 set_bit(nr, &sk->sk_wq_raw->flags); 2525 } 2526 2527 static inline void sk_clear_bit(int nr, struct sock *sk) 2528 { 2529 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2530 !sock_flag(sk, SOCK_FASYNC)) 2531 return; 2532 2533 clear_bit(nr, &sk->sk_wq_raw->flags); 2534 } 2535 2536 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2537 { 2538 if (sock_flag(sk, SOCK_FASYNC)) { 2539 rcu_read_lock(); 2540 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2541 rcu_read_unlock(); 2542 } 2543 } 2544 2545 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2546 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2547 * Note: for send buffers, TCP works better if we can build two skbs at 2548 * minimum. 2549 */ 2550 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2551 2552 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2553 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2554 2555 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2556 { 2557 u32 val; 2558 2559 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2560 return; 2561 2562 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2563 val = max_t(u32, val, sk_unused_reserved_mem(sk)); 2564 2565 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2566 } 2567 2568 /** 2569 * sk_page_frag - return an appropriate page_frag 2570 * @sk: socket 2571 * 2572 * Use the per task page_frag instead of the per socket one for 2573 * optimization when we know that we're in process context and own 2574 * everything that's associated with %current. 2575 * 2576 * Both direct reclaim and page faults can nest inside other 2577 * socket operations and end up recursing into sk_page_frag() 2578 * while it's already in use: explicitly avoid task page_frag 2579 * when users disable sk_use_task_frag. 2580 * 2581 * Return: a per task page_frag if context allows that, 2582 * otherwise a per socket one. 2583 */ 2584 static inline struct page_frag *sk_page_frag(struct sock *sk) 2585 { 2586 if (sk->sk_use_task_frag) 2587 return ¤t->task_frag; 2588 2589 return &sk->sk_frag; 2590 } 2591 2592 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2593 2594 /* 2595 * Default write policy as shown to user space via poll/select/SIGIO 2596 */ 2597 static inline bool sock_writeable(const struct sock *sk) 2598 { 2599 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2600 } 2601 2602 static inline gfp_t gfp_any(void) 2603 { 2604 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2605 } 2606 2607 static inline gfp_t gfp_memcg_charge(void) 2608 { 2609 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2610 } 2611 2612 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2613 { 2614 return noblock ? 0 : sk->sk_rcvtimeo; 2615 } 2616 2617 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2618 { 2619 return noblock ? 0 : sk->sk_sndtimeo; 2620 } 2621 2622 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2623 { 2624 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2625 2626 return v ?: 1; 2627 } 2628 2629 /* Alas, with timeout socket operations are not restartable. 2630 * Compare this to poll(). 2631 */ 2632 static inline int sock_intr_errno(long timeo) 2633 { 2634 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2635 } 2636 2637 struct sock_skb_cb { 2638 u32 dropcount; 2639 }; 2640 2641 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2642 * using skb->cb[] would keep using it directly and utilize its 2643 * alignement guarantee. 2644 */ 2645 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2646 sizeof(struct sock_skb_cb))) 2647 2648 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2649 SOCK_SKB_CB_OFFSET)) 2650 2651 #define sock_skb_cb_check_size(size) \ 2652 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2653 2654 static inline void 2655 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2656 { 2657 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2658 atomic_read(&sk->sk_drops) : 0; 2659 } 2660 2661 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2662 { 2663 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2664 2665 atomic_add(segs, &sk->sk_drops); 2666 } 2667 2668 static inline ktime_t sock_read_timestamp(struct sock *sk) 2669 { 2670 #if BITS_PER_LONG==32 2671 unsigned int seq; 2672 ktime_t kt; 2673 2674 do { 2675 seq = read_seqbegin(&sk->sk_stamp_seq); 2676 kt = sk->sk_stamp; 2677 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2678 2679 return kt; 2680 #else 2681 return READ_ONCE(sk->sk_stamp); 2682 #endif 2683 } 2684 2685 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2686 { 2687 #if BITS_PER_LONG==32 2688 write_seqlock(&sk->sk_stamp_seq); 2689 sk->sk_stamp = kt; 2690 write_sequnlock(&sk->sk_stamp_seq); 2691 #else 2692 WRITE_ONCE(sk->sk_stamp, kt); 2693 #endif 2694 } 2695 2696 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2697 struct sk_buff *skb); 2698 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2699 struct sk_buff *skb); 2700 2701 static inline void 2702 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2703 { 2704 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2705 u32 tsflags = READ_ONCE(sk->sk_tsflags); 2706 ktime_t kt = skb->tstamp; 2707 /* 2708 * generate control messages if 2709 * - receive time stamping in software requested 2710 * - software time stamp available and wanted 2711 * - hardware time stamps available and wanted 2712 */ 2713 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2714 (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2715 (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2716 (hwtstamps->hwtstamp && 2717 (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2718 __sock_recv_timestamp(msg, sk, skb); 2719 else 2720 sock_write_timestamp(sk, kt); 2721 2722 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb)) 2723 __sock_recv_wifi_status(msg, sk, skb); 2724 } 2725 2726 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2727 struct sk_buff *skb); 2728 2729 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2730 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2731 struct sk_buff *skb) 2732 { 2733 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \ 2734 (1UL << SOCK_RCVTSTAMP) | \ 2735 (1UL << SOCK_RCVMARK)) 2736 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2737 SOF_TIMESTAMPING_RAW_HARDWARE) 2738 2739 if (sk->sk_flags & FLAGS_RECV_CMSGS || 2740 READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY) 2741 __sock_recv_cmsgs(msg, sk, skb); 2742 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2743 sock_write_timestamp(sk, skb->tstamp); 2744 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP)) 2745 sock_write_timestamp(sk, 0); 2746 } 2747 2748 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2749 2750 /** 2751 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2752 * @sk: socket sending this packet 2753 * @tsflags: timestamping flags to use 2754 * @tx_flags: completed with instructions for time stamping 2755 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2756 * 2757 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2758 */ 2759 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2760 __u8 *tx_flags, __u32 *tskey) 2761 { 2762 if (unlikely(tsflags)) { 2763 __sock_tx_timestamp(tsflags, tx_flags); 2764 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2765 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2766 *tskey = atomic_inc_return(&sk->sk_tskey) - 1; 2767 } 2768 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2769 *tx_flags |= SKBTX_WIFI_STATUS; 2770 } 2771 2772 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2773 __u8 *tx_flags) 2774 { 2775 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2776 } 2777 2778 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2779 { 2780 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2781 &skb_shinfo(skb)->tskey); 2782 } 2783 2784 static inline bool sk_is_tcp(const struct sock *sk) 2785 { 2786 return sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP; 2787 } 2788 2789 /** 2790 * sk_eat_skb - Release a skb if it is no longer needed 2791 * @sk: socket to eat this skb from 2792 * @skb: socket buffer to eat 2793 * 2794 * This routine must be called with interrupts disabled or with the socket 2795 * locked so that the sk_buff queue operation is ok. 2796 */ 2797 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2798 { 2799 __skb_unlink(skb, &sk->sk_receive_queue); 2800 __kfree_skb(skb); 2801 } 2802 2803 static inline bool 2804 skb_sk_is_prefetched(struct sk_buff *skb) 2805 { 2806 #ifdef CONFIG_INET 2807 return skb->destructor == sock_pfree; 2808 #else 2809 return false; 2810 #endif /* CONFIG_INET */ 2811 } 2812 2813 /* This helper checks if a socket is a full socket, 2814 * ie _not_ a timewait or request socket. 2815 */ 2816 static inline bool sk_fullsock(const struct sock *sk) 2817 { 2818 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2819 } 2820 2821 static inline bool 2822 sk_is_refcounted(struct sock *sk) 2823 { 2824 /* Only full sockets have sk->sk_flags. */ 2825 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2826 } 2827 2828 /** 2829 * skb_steal_sock - steal a socket from an sk_buff 2830 * @skb: sk_buff to steal the socket from 2831 * @refcounted: is set to true if the socket is reference-counted 2832 * @prefetched: is set to true if the socket was assigned from bpf 2833 */ 2834 static inline struct sock * 2835 skb_steal_sock(struct sk_buff *skb, bool *refcounted, bool *prefetched) 2836 { 2837 if (skb->sk) { 2838 struct sock *sk = skb->sk; 2839 2840 *refcounted = true; 2841 *prefetched = skb_sk_is_prefetched(skb); 2842 if (*prefetched) 2843 *refcounted = sk_is_refcounted(sk); 2844 skb->destructor = NULL; 2845 skb->sk = NULL; 2846 return sk; 2847 } 2848 *prefetched = false; 2849 *refcounted = false; 2850 return NULL; 2851 } 2852 2853 /* Checks if this SKB belongs to an HW offloaded socket 2854 * and whether any SW fallbacks are required based on dev. 2855 * Check decrypted mark in case skb_orphan() cleared socket. 2856 */ 2857 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2858 struct net_device *dev) 2859 { 2860 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2861 struct sock *sk = skb->sk; 2862 2863 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2864 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2865 #ifdef CONFIG_TLS_DEVICE 2866 } else if (unlikely(skb->decrypted)) { 2867 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2868 kfree_skb(skb); 2869 skb = NULL; 2870 #endif 2871 } 2872 #endif 2873 2874 return skb; 2875 } 2876 2877 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2878 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2879 */ 2880 static inline bool sk_listener(const struct sock *sk) 2881 { 2882 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2883 } 2884 2885 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2886 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2887 int type); 2888 2889 bool sk_ns_capable(const struct sock *sk, 2890 struct user_namespace *user_ns, int cap); 2891 bool sk_capable(const struct sock *sk, int cap); 2892 bool sk_net_capable(const struct sock *sk, int cap); 2893 2894 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2895 2896 /* Take into consideration the size of the struct sk_buff overhead in the 2897 * determination of these values, since that is non-constant across 2898 * platforms. This makes socket queueing behavior and performance 2899 * not depend upon such differences. 2900 */ 2901 #define _SK_MEM_PACKETS 256 2902 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2903 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2904 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2905 2906 extern __u32 sysctl_wmem_max; 2907 extern __u32 sysctl_rmem_max; 2908 2909 extern int sysctl_tstamp_allow_data; 2910 extern int sysctl_optmem_max; 2911 2912 extern __u32 sysctl_wmem_default; 2913 extern __u32 sysctl_rmem_default; 2914 2915 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2916 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2917 2918 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2919 { 2920 /* Does this proto have per netns sysctl_wmem ? */ 2921 if (proto->sysctl_wmem_offset) 2922 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); 2923 2924 return READ_ONCE(*proto->sysctl_wmem); 2925 } 2926 2927 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2928 { 2929 /* Does this proto have per netns sysctl_rmem ? */ 2930 if (proto->sysctl_rmem_offset) 2931 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); 2932 2933 return READ_ONCE(*proto->sysctl_rmem); 2934 } 2935 2936 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2937 * Some wifi drivers need to tweak it to get more chunks. 2938 * They can use this helper from their ndo_start_xmit() 2939 */ 2940 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2941 { 2942 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2943 return; 2944 WRITE_ONCE(sk->sk_pacing_shift, val); 2945 } 2946 2947 /* if a socket is bound to a device, check that the given device 2948 * index is either the same or that the socket is bound to an L3 2949 * master device and the given device index is also enslaved to 2950 * that L3 master 2951 */ 2952 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2953 { 2954 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 2955 int mdif; 2956 2957 if (!bound_dev_if || bound_dev_if == dif) 2958 return true; 2959 2960 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2961 if (mdif && mdif == bound_dev_if) 2962 return true; 2963 2964 return false; 2965 } 2966 2967 void sock_def_readable(struct sock *sk); 2968 2969 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 2970 void sock_set_timestamp(struct sock *sk, int optname, bool valbool); 2971 int sock_set_timestamping(struct sock *sk, int optname, 2972 struct so_timestamping timestamping); 2973 2974 void sock_enable_timestamps(struct sock *sk); 2975 void sock_no_linger(struct sock *sk); 2976 void sock_set_keepalive(struct sock *sk); 2977 void sock_set_priority(struct sock *sk, u32 priority); 2978 void sock_set_rcvbuf(struct sock *sk, int val); 2979 void sock_set_mark(struct sock *sk, u32 val); 2980 void sock_set_reuseaddr(struct sock *sk); 2981 void sock_set_reuseport(struct sock *sk); 2982 void sock_set_sndtimeo(struct sock *sk, s64 secs); 2983 2984 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 2985 2986 int sock_get_timeout(long timeo, void *optval, bool old_timeval); 2987 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 2988 sockptr_t optval, int optlen, bool old_timeval); 2989 2990 int sock_ioctl_inout(struct sock *sk, unsigned int cmd, 2991 void __user *arg, void *karg, size_t size); 2992 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg); 2993 static inline bool sk_is_readable(struct sock *sk) 2994 { 2995 if (sk->sk_prot->sock_is_readable) 2996 return sk->sk_prot->sock_is_readable(sk); 2997 return false; 2998 } 2999 #endif /* _SOCK_H */ 3000