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 /* This is the per-socket lock. The spinlock provides a synchronization 80 * between user contexts and software interrupt processing, whereas the 81 * mini-semaphore synchronizes multiple users amongst themselves. 82 */ 83 typedef struct { 84 spinlock_t slock; 85 int owned; 86 wait_queue_head_t wq; 87 /* 88 * We express the mutex-alike socket_lock semantics 89 * to the lock validator by explicitly managing 90 * the slock as a lock variant (in addition to 91 * the slock itself): 92 */ 93 #ifdef CONFIG_DEBUG_LOCK_ALLOC 94 struct lockdep_map dep_map; 95 #endif 96 } socket_lock_t; 97 98 struct sock; 99 struct proto; 100 struct net; 101 102 typedef __u32 __bitwise __portpair; 103 typedef __u64 __bitwise __addrpair; 104 105 /** 106 * struct sock_common - minimal network layer representation of sockets 107 * @skc_daddr: Foreign IPv4 addr 108 * @skc_rcv_saddr: Bound local IPv4 addr 109 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr 110 * @skc_hash: hash value used with various protocol lookup tables 111 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 112 * @skc_dport: placeholder for inet_dport/tw_dport 113 * @skc_num: placeholder for inet_num/tw_num 114 * @skc_portpair: __u32 union of @skc_dport & @skc_num 115 * @skc_family: network address family 116 * @skc_state: Connection state 117 * @skc_reuse: %SO_REUSEADDR setting 118 * @skc_reuseport: %SO_REUSEPORT setting 119 * @skc_ipv6only: socket is IPV6 only 120 * @skc_net_refcnt: socket is using net ref counting 121 * @skc_bound_dev_if: bound device index if != 0 122 * @skc_bind_node: bind hash linkage for various protocol lookup tables 123 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 124 * @skc_prot: protocol handlers inside a network family 125 * @skc_net: reference to the network namespace of this socket 126 * @skc_v6_daddr: IPV6 destination address 127 * @skc_v6_rcv_saddr: IPV6 source address 128 * @skc_cookie: socket's cookie value 129 * @skc_node: main hash linkage for various protocol lookup tables 130 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 131 * @skc_tx_queue_mapping: tx queue number for this connection 132 * @skc_rx_queue_mapping: rx queue number for this connection 133 * @skc_flags: place holder for sk_flags 134 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 135 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 136 * @skc_listener: connection request listener socket (aka rsk_listener) 137 * [union with @skc_flags] 138 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row 139 * [union with @skc_flags] 140 * @skc_incoming_cpu: record/match cpu processing incoming packets 141 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) 142 * [union with @skc_incoming_cpu] 143 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number 144 * [union with @skc_incoming_cpu] 145 * @skc_refcnt: reference count 146 * 147 * This is the minimal network layer representation of sockets, the header 148 * for struct sock and struct inet_timewait_sock. 149 */ 150 struct sock_common { 151 union { 152 __addrpair skc_addrpair; 153 struct { 154 __be32 skc_daddr; 155 __be32 skc_rcv_saddr; 156 }; 157 }; 158 union { 159 unsigned int skc_hash; 160 __u16 skc_u16hashes[2]; 161 }; 162 /* skc_dport && skc_num must be grouped as well */ 163 union { 164 __portpair skc_portpair; 165 struct { 166 __be16 skc_dport; 167 __u16 skc_num; 168 }; 169 }; 170 171 unsigned short skc_family; 172 volatile unsigned char skc_state; 173 unsigned char skc_reuse:4; 174 unsigned char skc_reuseport:1; 175 unsigned char skc_ipv6only:1; 176 unsigned char skc_net_refcnt:1; 177 int skc_bound_dev_if; 178 union { 179 struct hlist_node skc_bind_node; 180 struct hlist_node skc_portaddr_node; 181 }; 182 struct proto *skc_prot; 183 possible_net_t skc_net; 184 185 #if IS_ENABLED(CONFIG_IPV6) 186 struct in6_addr skc_v6_daddr; 187 struct in6_addr skc_v6_rcv_saddr; 188 #endif 189 190 atomic64_t skc_cookie; 191 192 /* following fields are padding to force 193 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 194 * assuming IPV6 is enabled. We use this padding differently 195 * for different kind of 'sockets' 196 */ 197 union { 198 unsigned long skc_flags; 199 struct sock *skc_listener; /* request_sock */ 200 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 201 }; 202 /* 203 * fields between dontcopy_begin/dontcopy_end 204 * are not copied in sock_copy() 205 */ 206 /* private: */ 207 int skc_dontcopy_begin[0]; 208 /* public: */ 209 union { 210 struct hlist_node skc_node; 211 struct hlist_nulls_node skc_nulls_node; 212 }; 213 unsigned short skc_tx_queue_mapping; 214 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 215 unsigned short skc_rx_queue_mapping; 216 #endif 217 union { 218 int skc_incoming_cpu; 219 u32 skc_rcv_wnd; 220 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 221 }; 222 223 refcount_t skc_refcnt; 224 /* private: */ 225 int skc_dontcopy_end[0]; 226 union { 227 u32 skc_rxhash; 228 u32 skc_window_clamp; 229 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 230 }; 231 /* public: */ 232 }; 233 234 struct bpf_local_storage; 235 struct sk_filter; 236 237 /** 238 * struct sock - network layer representation of sockets 239 * @__sk_common: shared layout with inet_timewait_sock 240 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 241 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 242 * @sk_lock: synchronizer 243 * @sk_kern_sock: True if sock is using kernel lock classes 244 * @sk_rcvbuf: size of receive buffer in bytes 245 * @sk_wq: sock wait queue and async head 246 * @sk_rx_dst: receive input route used by early demux 247 * @sk_rx_dst_ifindex: ifindex for @sk_rx_dst 248 * @sk_rx_dst_cookie: cookie for @sk_rx_dst 249 * @sk_dst_cache: destination cache 250 * @sk_dst_pending_confirm: need to confirm neighbour 251 * @sk_policy: flow policy 252 * @sk_receive_queue: incoming packets 253 * @sk_wmem_alloc: transmit queue bytes committed 254 * @sk_tsq_flags: TCP Small Queues flags 255 * @sk_write_queue: Packet sending queue 256 * @sk_omem_alloc: "o" is "option" or "other" 257 * @sk_wmem_queued: persistent queue size 258 * @sk_forward_alloc: space allocated forward 259 * @sk_reserved_mem: space reserved and non-reclaimable for the socket 260 * @sk_napi_id: id of the last napi context to receive data for sk 261 * @sk_ll_usec: usecs to busypoll when there is no data 262 * @sk_allocation: allocation mode 263 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 264 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 265 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 266 * @sk_sndbuf: size of send buffer in bytes 267 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 268 * @sk_no_check_rx: allow zero checksum in RX packets 269 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 270 * @sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden. 271 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 272 * @sk_gso_max_size: Maximum GSO segment size to build 273 * @sk_gso_max_segs: Maximum number of GSO segments 274 * @sk_pacing_shift: scaling factor for TCP Small Queues 275 * @sk_lingertime: %SO_LINGER l_linger setting 276 * @sk_backlog: always used with the per-socket spinlock held 277 * @sk_callback_lock: used with the callbacks in the end of this struct 278 * @sk_error_queue: rarely used 279 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 280 * IPV6_ADDRFORM for instance) 281 * @sk_err: last error 282 * @sk_err_soft: errors that don't cause failure but are the cause of a 283 * persistent failure not just 'timed out' 284 * @sk_drops: raw/udp drops counter 285 * @sk_ack_backlog: current listen backlog 286 * @sk_max_ack_backlog: listen backlog set in listen() 287 * @sk_uid: user id of owner 288 * @sk_prefer_busy_poll: prefer busypolling over softirq processing 289 * @sk_busy_poll_budget: napi processing budget when busypolling 290 * @sk_priority: %SO_PRIORITY setting 291 * @sk_type: socket type (%SOCK_STREAM, etc) 292 * @sk_protocol: which protocol this socket belongs in this network family 293 * @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred 294 * @sk_peer_pid: &struct pid for this socket's peer 295 * @sk_peer_cred: %SO_PEERCRED setting 296 * @sk_rcvlowat: %SO_RCVLOWAT setting 297 * @sk_rcvtimeo: %SO_RCVTIMEO setting 298 * @sk_sndtimeo: %SO_SNDTIMEO setting 299 * @sk_txhash: computed flow hash for use on transmit 300 * @sk_txrehash: enable TX hash rethink 301 * @sk_filter: socket filtering instructions 302 * @sk_timer: sock cleanup timer 303 * @sk_stamp: time stamp of last packet received 304 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 305 * @sk_tsflags: SO_TIMESTAMPING flags 306 * @sk_use_task_frag: allow sk_page_frag() to use current->task_frag. 307 * Sockets that can be used under memory reclaim should 308 * set this to false. 309 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock 310 * for timestamping 311 * @sk_tskey: counter to disambiguate concurrent tstamp requests 312 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 313 * @sk_socket: Identd and reporting IO signals 314 * @sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock. 315 * @sk_frag: cached page frag 316 * @sk_peek_off: current peek_offset value 317 * @sk_send_head: front of stuff to transmit 318 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] 319 * @sk_security: used by security modules 320 * @sk_mark: generic packet mark 321 * @sk_cgrp_data: cgroup data for this cgroup 322 * @sk_memcg: this socket's memory cgroup association 323 * @sk_write_pending: a write to stream socket waits to start 324 * @sk_disconnects: number of disconnect operations performed on this sock 325 * @sk_state_change: callback to indicate change in the state of the sock 326 * @sk_data_ready: callback to indicate there is data to be processed 327 * @sk_write_space: callback to indicate there is bf sending space available 328 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 329 * @sk_backlog_rcv: callback to process the backlog 330 * @sk_validate_xmit_skb: ptr to an optional validate function 331 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 332 * @sk_reuseport_cb: reuseport group container 333 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage 334 * @sk_rcu: used during RCU grace period 335 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 336 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 337 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME 338 * @sk_txtime_unused: unused txtime flags 339 * @ns_tracker: tracker for netns reference 340 * @sk_user_frags: xarray of pages the user is holding a reference on. 341 */ 342 struct sock { 343 /* 344 * Now struct inet_timewait_sock also uses sock_common, so please just 345 * don't add nothing before this first member (__sk_common) --acme 346 */ 347 struct sock_common __sk_common; 348 #define sk_node __sk_common.skc_node 349 #define sk_nulls_node __sk_common.skc_nulls_node 350 #define sk_refcnt __sk_common.skc_refcnt 351 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 352 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 353 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 354 #endif 355 356 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 357 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 358 #define sk_hash __sk_common.skc_hash 359 #define sk_portpair __sk_common.skc_portpair 360 #define sk_num __sk_common.skc_num 361 #define sk_dport __sk_common.skc_dport 362 #define sk_addrpair __sk_common.skc_addrpair 363 #define sk_daddr __sk_common.skc_daddr 364 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 365 #define sk_family __sk_common.skc_family 366 #define sk_state __sk_common.skc_state 367 #define sk_reuse __sk_common.skc_reuse 368 #define sk_reuseport __sk_common.skc_reuseport 369 #define sk_ipv6only __sk_common.skc_ipv6only 370 #define sk_net_refcnt __sk_common.skc_net_refcnt 371 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 372 #define sk_bind_node __sk_common.skc_bind_node 373 #define sk_prot __sk_common.skc_prot 374 #define sk_net __sk_common.skc_net 375 #define sk_v6_daddr __sk_common.skc_v6_daddr 376 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 377 #define sk_cookie __sk_common.skc_cookie 378 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 379 #define sk_flags __sk_common.skc_flags 380 #define sk_rxhash __sk_common.skc_rxhash 381 382 __cacheline_group_begin(sock_write_rx); 383 384 atomic_t sk_drops; 385 __s32 sk_peek_off; 386 struct sk_buff_head sk_error_queue; 387 struct sk_buff_head sk_receive_queue; 388 /* 389 * The backlog queue is special, it is always used with 390 * the per-socket spinlock held and requires low latency 391 * access. Therefore we special case it's implementation. 392 * Note : rmem_alloc is in this structure to fill a hole 393 * on 64bit arches, not because its logically part of 394 * backlog. 395 */ 396 struct { 397 atomic_t rmem_alloc; 398 int len; 399 struct sk_buff *head; 400 struct sk_buff *tail; 401 } sk_backlog; 402 #define sk_rmem_alloc sk_backlog.rmem_alloc 403 404 __cacheline_group_end(sock_write_rx); 405 406 __cacheline_group_begin(sock_read_rx); 407 /* early demux fields */ 408 struct dst_entry __rcu *sk_rx_dst; 409 int sk_rx_dst_ifindex; 410 u32 sk_rx_dst_cookie; 411 412 #ifdef CONFIG_NET_RX_BUSY_POLL 413 unsigned int sk_ll_usec; 414 unsigned int sk_napi_id; 415 u16 sk_busy_poll_budget; 416 u8 sk_prefer_busy_poll; 417 #endif 418 u8 sk_userlocks; 419 int sk_rcvbuf; 420 421 struct sk_filter __rcu *sk_filter; 422 union { 423 struct socket_wq __rcu *sk_wq; 424 /* private: */ 425 struct socket_wq *sk_wq_raw; 426 /* public: */ 427 }; 428 429 void (*sk_data_ready)(struct sock *sk); 430 long sk_rcvtimeo; 431 int sk_rcvlowat; 432 __cacheline_group_end(sock_read_rx); 433 434 __cacheline_group_begin(sock_read_rxtx); 435 int sk_err; 436 struct socket *sk_socket; 437 struct mem_cgroup *sk_memcg; 438 #ifdef CONFIG_XFRM 439 struct xfrm_policy __rcu *sk_policy[2]; 440 #endif 441 __cacheline_group_end(sock_read_rxtx); 442 443 __cacheline_group_begin(sock_write_rxtx); 444 socket_lock_t sk_lock; 445 u32 sk_reserved_mem; 446 int sk_forward_alloc; 447 u32 sk_tsflags; 448 __cacheline_group_end(sock_write_rxtx); 449 450 __cacheline_group_begin(sock_write_tx); 451 int sk_write_pending; 452 atomic_t sk_omem_alloc; 453 int sk_sndbuf; 454 455 int sk_wmem_queued; 456 refcount_t sk_wmem_alloc; 457 unsigned long sk_tsq_flags; 458 union { 459 struct sk_buff *sk_send_head; 460 struct rb_root tcp_rtx_queue; 461 }; 462 struct sk_buff_head sk_write_queue; 463 u32 sk_dst_pending_confirm; 464 u32 sk_pacing_status; /* see enum sk_pacing */ 465 struct page_frag sk_frag; 466 struct timer_list sk_timer; 467 468 unsigned long sk_pacing_rate; /* bytes per second */ 469 atomic_t sk_zckey; 470 atomic_t sk_tskey; 471 __cacheline_group_end(sock_write_tx); 472 473 __cacheline_group_begin(sock_read_tx); 474 unsigned long sk_max_pacing_rate; 475 long sk_sndtimeo; 476 u32 sk_priority; 477 u32 sk_mark; 478 struct dst_entry __rcu *sk_dst_cache; 479 netdev_features_t sk_route_caps; 480 #ifdef CONFIG_SOCK_VALIDATE_XMIT 481 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 482 struct net_device *dev, 483 struct sk_buff *skb); 484 #endif 485 u16 sk_gso_type; 486 u16 sk_gso_max_segs; 487 unsigned int sk_gso_max_size; 488 gfp_t sk_allocation; 489 u32 sk_txhash; 490 u8 sk_pacing_shift; 491 bool sk_use_task_frag; 492 __cacheline_group_end(sock_read_tx); 493 494 /* 495 * Because of non atomicity rules, all 496 * changes are protected by socket lock. 497 */ 498 u8 sk_gso_disabled : 1, 499 sk_kern_sock : 1, 500 sk_no_check_tx : 1, 501 sk_no_check_rx : 1; 502 u8 sk_shutdown; 503 u16 sk_type; 504 u16 sk_protocol; 505 unsigned long sk_lingertime; 506 struct proto *sk_prot_creator; 507 rwlock_t sk_callback_lock; 508 int sk_err_soft; 509 u32 sk_ack_backlog; 510 u32 sk_max_ack_backlog; 511 kuid_t sk_uid; 512 spinlock_t sk_peer_lock; 513 int sk_bind_phc; 514 struct pid *sk_peer_pid; 515 const struct cred *sk_peer_cred; 516 517 ktime_t sk_stamp; 518 #if BITS_PER_LONG==32 519 seqlock_t sk_stamp_seq; 520 #endif 521 int sk_disconnects; 522 523 u8 sk_txrehash; 524 u8 sk_clockid; 525 u8 sk_txtime_deadline_mode : 1, 526 sk_txtime_report_errors : 1, 527 sk_txtime_unused : 6; 528 529 void *sk_user_data; 530 #ifdef CONFIG_SECURITY 531 void *sk_security; 532 #endif 533 struct sock_cgroup_data sk_cgrp_data; 534 void (*sk_state_change)(struct sock *sk); 535 void (*sk_write_space)(struct sock *sk); 536 void (*sk_error_report)(struct sock *sk); 537 int (*sk_backlog_rcv)(struct sock *sk, 538 struct sk_buff *skb); 539 void (*sk_destruct)(struct sock *sk); 540 struct sock_reuseport __rcu *sk_reuseport_cb; 541 #ifdef CONFIG_BPF_SYSCALL 542 struct bpf_local_storage __rcu *sk_bpf_storage; 543 #endif 544 struct rcu_head sk_rcu; 545 netns_tracker ns_tracker; 546 struct xarray sk_user_frags; 547 }; 548 549 struct sock_bh_locked { 550 struct sock *sock; 551 local_lock_t bh_lock; 552 }; 553 554 enum sk_pacing { 555 SK_PACING_NONE = 0, 556 SK_PACING_NEEDED = 1, 557 SK_PACING_FQ = 2, 558 }; 559 560 /* flag bits in sk_user_data 561 * 562 * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might 563 * not be suitable for copying when cloning the socket. For instance, 564 * it can point to a reference counted object. sk_user_data bottom 565 * bit is set if pointer must not be copied. 566 * 567 * - SK_USER_DATA_BPF: Mark whether sk_user_data field is 568 * managed/owned by a BPF reuseport array. This bit should be set 569 * when sk_user_data's sk is added to the bpf's reuseport_array. 570 * 571 * - SK_USER_DATA_PSOCK: Mark whether pointer stored in 572 * sk_user_data points to psock type. This bit should be set 573 * when sk_user_data is assigned to a psock object. 574 */ 575 #define SK_USER_DATA_NOCOPY 1UL 576 #define SK_USER_DATA_BPF 2UL 577 #define SK_USER_DATA_PSOCK 4UL 578 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\ 579 SK_USER_DATA_PSOCK) 580 581 /** 582 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied 583 * @sk: socket 584 */ 585 static inline bool sk_user_data_is_nocopy(const struct sock *sk) 586 { 587 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); 588 } 589 590 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 591 592 /** 593 * __locked_read_sk_user_data_with_flags - return the pointer 594 * only if argument flags all has been set in sk_user_data. Otherwise 595 * return NULL 596 * 597 * @sk: socket 598 * @flags: flag bits 599 * 600 * The caller must be holding sk->sk_callback_lock. 601 */ 602 static inline void * 603 __locked_read_sk_user_data_with_flags(const struct sock *sk, 604 uintptr_t flags) 605 { 606 uintptr_t sk_user_data = 607 (uintptr_t)rcu_dereference_check(__sk_user_data(sk), 608 lockdep_is_held(&sk->sk_callback_lock)); 609 610 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 611 612 if ((sk_user_data & flags) == flags) 613 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 614 return NULL; 615 } 616 617 /** 618 * __rcu_dereference_sk_user_data_with_flags - return the pointer 619 * only if argument flags all has been set in sk_user_data. Otherwise 620 * return NULL 621 * 622 * @sk: socket 623 * @flags: flag bits 624 */ 625 static inline void * 626 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk, 627 uintptr_t flags) 628 { 629 uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk)); 630 631 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 632 633 if ((sk_user_data & flags) == flags) 634 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 635 return NULL; 636 } 637 638 #define rcu_dereference_sk_user_data(sk) \ 639 __rcu_dereference_sk_user_data_with_flags(sk, 0) 640 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \ 641 ({ \ 642 uintptr_t __tmp1 = (uintptr_t)(ptr), \ 643 __tmp2 = (uintptr_t)(flags); \ 644 WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \ 645 WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \ 646 rcu_assign_pointer(__sk_user_data((sk)), \ 647 __tmp1 | __tmp2); \ 648 }) 649 #define rcu_assign_sk_user_data(sk, ptr) \ 650 __rcu_assign_sk_user_data_with_flags(sk, ptr, 0) 651 652 static inline 653 struct net *sock_net(const struct sock *sk) 654 { 655 return read_pnet(&sk->sk_net); 656 } 657 658 static inline 659 void sock_net_set(struct sock *sk, struct net *net) 660 { 661 write_pnet(&sk->sk_net, net); 662 } 663 664 /* 665 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 666 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 667 * on a socket means that the socket will reuse everybody else's port 668 * without looking at the other's sk_reuse value. 669 */ 670 671 #define SK_NO_REUSE 0 672 #define SK_CAN_REUSE 1 673 #define SK_FORCE_REUSE 2 674 675 int sk_set_peek_off(struct sock *sk, int val); 676 677 static inline int sk_peek_offset(const struct sock *sk, int flags) 678 { 679 if (unlikely(flags & MSG_PEEK)) { 680 return READ_ONCE(sk->sk_peek_off); 681 } 682 683 return 0; 684 } 685 686 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 687 { 688 s32 off = READ_ONCE(sk->sk_peek_off); 689 690 if (unlikely(off >= 0)) { 691 off = max_t(s32, off - val, 0); 692 WRITE_ONCE(sk->sk_peek_off, off); 693 } 694 } 695 696 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 697 { 698 sk_peek_offset_bwd(sk, -val); 699 } 700 701 /* 702 * Hashed lists helper routines 703 */ 704 static inline struct sock *sk_entry(const struct hlist_node *node) 705 { 706 return hlist_entry(node, struct sock, sk_node); 707 } 708 709 static inline struct sock *__sk_head(const struct hlist_head *head) 710 { 711 return hlist_entry(head->first, struct sock, sk_node); 712 } 713 714 static inline struct sock *sk_head(const struct hlist_head *head) 715 { 716 return hlist_empty(head) ? NULL : __sk_head(head); 717 } 718 719 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 720 { 721 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 722 } 723 724 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 725 { 726 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 727 } 728 729 static inline struct sock *sk_next(const struct sock *sk) 730 { 731 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 732 } 733 734 static inline struct sock *sk_nulls_next(const struct sock *sk) 735 { 736 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 737 hlist_nulls_entry(sk->sk_nulls_node.next, 738 struct sock, sk_nulls_node) : 739 NULL; 740 } 741 742 static inline bool sk_unhashed(const struct sock *sk) 743 { 744 return hlist_unhashed(&sk->sk_node); 745 } 746 747 static inline bool sk_hashed(const struct sock *sk) 748 { 749 return !sk_unhashed(sk); 750 } 751 752 static inline void sk_node_init(struct hlist_node *node) 753 { 754 node->pprev = NULL; 755 } 756 757 static inline void __sk_del_node(struct sock *sk) 758 { 759 __hlist_del(&sk->sk_node); 760 } 761 762 /* NB: equivalent to hlist_del_init_rcu */ 763 static inline bool __sk_del_node_init(struct sock *sk) 764 { 765 if (sk_hashed(sk)) { 766 __sk_del_node(sk); 767 sk_node_init(&sk->sk_node); 768 return true; 769 } 770 return false; 771 } 772 773 /* Grab socket reference count. This operation is valid only 774 when sk is ALREADY grabbed f.e. it is found in hash table 775 or a list and the lookup is made under lock preventing hash table 776 modifications. 777 */ 778 779 static __always_inline void sock_hold(struct sock *sk) 780 { 781 refcount_inc(&sk->sk_refcnt); 782 } 783 784 /* Ungrab socket in the context, which assumes that socket refcnt 785 cannot hit zero, f.e. it is true in context of any socketcall. 786 */ 787 static __always_inline void __sock_put(struct sock *sk) 788 { 789 refcount_dec(&sk->sk_refcnt); 790 } 791 792 static inline bool sk_del_node_init(struct sock *sk) 793 { 794 bool rc = __sk_del_node_init(sk); 795 796 if (rc) { 797 /* paranoid for a while -acme */ 798 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 799 __sock_put(sk); 800 } 801 return rc; 802 } 803 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 804 805 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 806 { 807 if (sk_hashed(sk)) { 808 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 809 return true; 810 } 811 return false; 812 } 813 814 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 815 { 816 bool rc = __sk_nulls_del_node_init_rcu(sk); 817 818 if (rc) { 819 /* paranoid for a while -acme */ 820 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 821 __sock_put(sk); 822 } 823 return rc; 824 } 825 826 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 827 { 828 hlist_add_head(&sk->sk_node, list); 829 } 830 831 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 832 { 833 sock_hold(sk); 834 __sk_add_node(sk, list); 835 } 836 837 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 838 { 839 sock_hold(sk); 840 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 841 sk->sk_family == AF_INET6) 842 hlist_add_tail_rcu(&sk->sk_node, list); 843 else 844 hlist_add_head_rcu(&sk->sk_node, list); 845 } 846 847 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 848 { 849 sock_hold(sk); 850 hlist_add_tail_rcu(&sk->sk_node, list); 851 } 852 853 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 854 { 855 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 856 } 857 858 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 859 { 860 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 861 } 862 863 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 864 { 865 sock_hold(sk); 866 __sk_nulls_add_node_rcu(sk, list); 867 } 868 869 static inline void __sk_del_bind_node(struct sock *sk) 870 { 871 __hlist_del(&sk->sk_bind_node); 872 } 873 874 static inline void sk_add_bind_node(struct sock *sk, 875 struct hlist_head *list) 876 { 877 hlist_add_head(&sk->sk_bind_node, list); 878 } 879 880 #define sk_for_each(__sk, list) \ 881 hlist_for_each_entry(__sk, list, sk_node) 882 #define sk_for_each_rcu(__sk, list) \ 883 hlist_for_each_entry_rcu(__sk, list, sk_node) 884 #define sk_nulls_for_each(__sk, node, list) \ 885 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 886 #define sk_nulls_for_each_rcu(__sk, node, list) \ 887 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 888 #define sk_for_each_from(__sk) \ 889 hlist_for_each_entry_from(__sk, sk_node) 890 #define sk_nulls_for_each_from(__sk, node) \ 891 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 892 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 893 #define sk_for_each_safe(__sk, tmp, list) \ 894 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 895 #define sk_for_each_bound(__sk, list) \ 896 hlist_for_each_entry(__sk, list, sk_bind_node) 897 #define sk_for_each_bound_safe(__sk, tmp, list) \ 898 hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node) 899 900 /** 901 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 902 * @tpos: the type * to use as a loop cursor. 903 * @pos: the &struct hlist_node to use as a loop cursor. 904 * @head: the head for your list. 905 * @offset: offset of hlist_node within the struct. 906 * 907 */ 908 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 909 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 910 pos != NULL && \ 911 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 912 pos = rcu_dereference(hlist_next_rcu(pos))) 913 914 static inline struct user_namespace *sk_user_ns(const struct sock *sk) 915 { 916 /* Careful only use this in a context where these parameters 917 * can not change and must all be valid, such as recvmsg from 918 * userspace. 919 */ 920 return sk->sk_socket->file->f_cred->user_ns; 921 } 922 923 /* Sock flags */ 924 enum sock_flags { 925 SOCK_DEAD, 926 SOCK_DONE, 927 SOCK_URGINLINE, 928 SOCK_KEEPOPEN, 929 SOCK_LINGER, 930 SOCK_DESTROY, 931 SOCK_BROADCAST, 932 SOCK_TIMESTAMP, 933 SOCK_ZAPPED, 934 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 935 SOCK_DBG, /* %SO_DEBUG setting */ 936 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 937 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 938 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 939 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 940 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 941 SOCK_FASYNC, /* fasync() active */ 942 SOCK_RXQ_OVFL, 943 SOCK_ZEROCOPY, /* buffers from userspace */ 944 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 945 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 946 * Will use last 4 bytes of packet sent from 947 * user-space instead. 948 */ 949 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 950 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 951 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 952 SOCK_TXTIME, 953 SOCK_XDP, /* XDP is attached */ 954 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 955 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */ 956 SOCK_RCVPRIORITY, /* Receive SO_PRIORITY ancillary data with packet */ 957 }; 958 959 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 960 /* 961 * The highest bit of sk_tsflags is reserved for kernel-internal 962 * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that 963 * SOF_TIMESTAMPING* values do not reach this reserved area 964 */ 965 #define SOCKCM_FLAG_TS_OPT_ID BIT(31) 966 967 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk) 968 { 969 nsk->sk_flags = osk->sk_flags; 970 } 971 972 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 973 { 974 __set_bit(flag, &sk->sk_flags); 975 } 976 977 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 978 { 979 __clear_bit(flag, &sk->sk_flags); 980 } 981 982 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 983 int valbool) 984 { 985 if (valbool) 986 sock_set_flag(sk, bit); 987 else 988 sock_reset_flag(sk, bit); 989 } 990 991 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 992 { 993 return test_bit(flag, &sk->sk_flags); 994 } 995 996 #ifdef CONFIG_NET 997 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 998 static inline int sk_memalloc_socks(void) 999 { 1000 return static_branch_unlikely(&memalloc_socks_key); 1001 } 1002 1003 void __receive_sock(struct file *file); 1004 #else 1005 1006 static inline int sk_memalloc_socks(void) 1007 { 1008 return 0; 1009 } 1010 1011 static inline void __receive_sock(struct file *file) 1012 { } 1013 #endif 1014 1015 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 1016 { 1017 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 1018 } 1019 1020 static inline void sk_acceptq_removed(struct sock *sk) 1021 { 1022 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 1023 } 1024 1025 static inline void sk_acceptq_added(struct sock *sk) 1026 { 1027 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 1028 } 1029 1030 /* Note: If you think the test should be: 1031 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 1032 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 1033 */ 1034 static inline bool sk_acceptq_is_full(const struct sock *sk) 1035 { 1036 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 1037 } 1038 1039 /* 1040 * Compute minimal free write space needed to queue new packets. 1041 */ 1042 static inline int sk_stream_min_wspace(const struct sock *sk) 1043 { 1044 return READ_ONCE(sk->sk_wmem_queued) >> 1; 1045 } 1046 1047 static inline int sk_stream_wspace(const struct sock *sk) 1048 { 1049 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 1050 } 1051 1052 static inline void sk_wmem_queued_add(struct sock *sk, int val) 1053 { 1054 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 1055 } 1056 1057 static inline void sk_forward_alloc_add(struct sock *sk, int val) 1058 { 1059 /* Paired with lockless reads of sk->sk_forward_alloc */ 1060 WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val); 1061 } 1062 1063 void sk_stream_write_space(struct sock *sk); 1064 1065 /* OOB backlog add */ 1066 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 1067 { 1068 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 1069 skb_dst_force(skb); 1070 1071 if (!sk->sk_backlog.tail) 1072 WRITE_ONCE(sk->sk_backlog.head, skb); 1073 else 1074 sk->sk_backlog.tail->next = skb; 1075 1076 WRITE_ONCE(sk->sk_backlog.tail, skb); 1077 skb->next = NULL; 1078 } 1079 1080 /* 1081 * Take into account size of receive queue and backlog queue 1082 * Do not take into account this skb truesize, 1083 * to allow even a single big packet to come. 1084 */ 1085 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 1086 { 1087 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 1088 1089 return qsize > limit; 1090 } 1091 1092 /* The per-socket spinlock must be held here. */ 1093 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 1094 unsigned int limit) 1095 { 1096 if (sk_rcvqueues_full(sk, limit)) 1097 return -ENOBUFS; 1098 1099 /* 1100 * If the skb was allocated from pfmemalloc reserves, only 1101 * allow SOCK_MEMALLOC sockets to use it as this socket is 1102 * helping free memory 1103 */ 1104 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1105 return -ENOMEM; 1106 1107 __sk_add_backlog(sk, skb); 1108 sk->sk_backlog.len += skb->truesize; 1109 return 0; 1110 } 1111 1112 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1113 1114 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)); 1115 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)); 1116 1117 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1118 { 1119 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1120 return __sk_backlog_rcv(sk, skb); 1121 1122 return INDIRECT_CALL_INET(sk->sk_backlog_rcv, 1123 tcp_v6_do_rcv, 1124 tcp_v4_do_rcv, 1125 sk, skb); 1126 } 1127 1128 static inline void sk_incoming_cpu_update(struct sock *sk) 1129 { 1130 int cpu = raw_smp_processor_id(); 1131 1132 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1133 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1134 } 1135 1136 1137 static inline void sock_rps_save_rxhash(struct sock *sk, 1138 const struct sk_buff *skb) 1139 { 1140 #ifdef CONFIG_RPS 1141 /* The following WRITE_ONCE() is paired with the READ_ONCE() 1142 * here, and another one in sock_rps_record_flow(). 1143 */ 1144 if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash)) 1145 WRITE_ONCE(sk->sk_rxhash, skb->hash); 1146 #endif 1147 } 1148 1149 static inline void sock_rps_reset_rxhash(struct sock *sk) 1150 { 1151 #ifdef CONFIG_RPS 1152 /* Paired with READ_ONCE() in sock_rps_record_flow() */ 1153 WRITE_ONCE(sk->sk_rxhash, 0); 1154 #endif 1155 } 1156 1157 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1158 ({ int __rc, __dis = __sk->sk_disconnects; \ 1159 release_sock(__sk); \ 1160 __rc = __condition; \ 1161 if (!__rc) { \ 1162 *(__timeo) = wait_woken(__wait, \ 1163 TASK_INTERRUPTIBLE, \ 1164 *(__timeo)); \ 1165 } \ 1166 sched_annotate_sleep(); \ 1167 lock_sock(__sk); \ 1168 __rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \ 1169 __rc; \ 1170 }) 1171 1172 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1173 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1174 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1175 int sk_stream_error(struct sock *sk, int flags, int err); 1176 void sk_stream_kill_queues(struct sock *sk); 1177 void sk_set_memalloc(struct sock *sk); 1178 void sk_clear_memalloc(struct sock *sk); 1179 1180 void __sk_flush_backlog(struct sock *sk); 1181 1182 static inline bool sk_flush_backlog(struct sock *sk) 1183 { 1184 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1185 __sk_flush_backlog(sk); 1186 return true; 1187 } 1188 return false; 1189 } 1190 1191 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1192 1193 struct request_sock_ops; 1194 struct timewait_sock_ops; 1195 struct inet_hashinfo; 1196 struct raw_hashinfo; 1197 struct smc_hashinfo; 1198 struct module; 1199 struct sk_psock; 1200 1201 /* 1202 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1203 * un-modified. Special care is taken when initializing object to zero. 1204 */ 1205 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1206 { 1207 if (offsetof(struct sock, sk_node.next) != 0) 1208 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1209 memset(&sk->sk_node.pprev, 0, 1210 size - offsetof(struct sock, sk_node.pprev)); 1211 } 1212 1213 struct proto_accept_arg { 1214 int flags; 1215 int err; 1216 int is_empty; 1217 bool kern; 1218 }; 1219 1220 /* Networking protocol blocks we attach to sockets. 1221 * socket layer -> transport layer interface 1222 */ 1223 struct proto { 1224 void (*close)(struct sock *sk, 1225 long timeout); 1226 int (*pre_connect)(struct sock *sk, 1227 struct sockaddr *uaddr, 1228 int addr_len); 1229 int (*connect)(struct sock *sk, 1230 struct sockaddr *uaddr, 1231 int addr_len); 1232 int (*disconnect)(struct sock *sk, int flags); 1233 1234 struct sock * (*accept)(struct sock *sk, 1235 struct proto_accept_arg *arg); 1236 1237 int (*ioctl)(struct sock *sk, int cmd, 1238 int *karg); 1239 int (*init)(struct sock *sk); 1240 void (*destroy)(struct sock *sk); 1241 void (*shutdown)(struct sock *sk, int how); 1242 int (*setsockopt)(struct sock *sk, int level, 1243 int optname, sockptr_t optval, 1244 unsigned int optlen); 1245 int (*getsockopt)(struct sock *sk, int level, 1246 int optname, char __user *optval, 1247 int __user *option); 1248 void (*keepalive)(struct sock *sk, int valbool); 1249 #ifdef CONFIG_COMPAT 1250 int (*compat_ioctl)(struct sock *sk, 1251 unsigned int cmd, unsigned long arg); 1252 #endif 1253 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1254 size_t len); 1255 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1256 size_t len, int flags, int *addr_len); 1257 void (*splice_eof)(struct socket *sock); 1258 int (*bind)(struct sock *sk, 1259 struct sockaddr *addr, int addr_len); 1260 int (*bind_add)(struct sock *sk, 1261 struct sockaddr *addr, int addr_len); 1262 1263 int (*backlog_rcv) (struct sock *sk, 1264 struct sk_buff *skb); 1265 bool (*bpf_bypass_getsockopt)(int level, 1266 int optname); 1267 1268 void (*release_cb)(struct sock *sk); 1269 1270 /* Keeping track of sk's, looking them up, and port selection methods. */ 1271 int (*hash)(struct sock *sk); 1272 void (*unhash)(struct sock *sk); 1273 void (*rehash)(struct sock *sk); 1274 int (*get_port)(struct sock *sk, unsigned short snum); 1275 void (*put_port)(struct sock *sk); 1276 #ifdef CONFIG_BPF_SYSCALL 1277 int (*psock_update_sk_prot)(struct sock *sk, 1278 struct sk_psock *psock, 1279 bool restore); 1280 #endif 1281 1282 /* Keeping track of sockets in use */ 1283 #ifdef CONFIG_PROC_FS 1284 unsigned int inuse_idx; 1285 #endif 1286 1287 #if IS_ENABLED(CONFIG_MPTCP) 1288 int (*forward_alloc_get)(const struct sock *sk); 1289 #endif 1290 1291 bool (*stream_memory_free)(const struct sock *sk, int wake); 1292 bool (*sock_is_readable)(struct sock *sk); 1293 /* Memory pressure */ 1294 void (*enter_memory_pressure)(struct sock *sk); 1295 void (*leave_memory_pressure)(struct sock *sk); 1296 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1297 int __percpu *per_cpu_fw_alloc; 1298 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1299 1300 /* 1301 * Pressure flag: try to collapse. 1302 * Technical note: it is used by multiple contexts non atomically. 1303 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes. 1304 * All the __sk_mem_schedule() is of this nature: accounting 1305 * is strict, actions are advisory and have some latency. 1306 */ 1307 unsigned long *memory_pressure; 1308 long *sysctl_mem; 1309 1310 int *sysctl_wmem; 1311 int *sysctl_rmem; 1312 u32 sysctl_wmem_offset; 1313 u32 sysctl_rmem_offset; 1314 1315 int max_header; 1316 bool no_autobind; 1317 1318 struct kmem_cache *slab; 1319 unsigned int obj_size; 1320 unsigned int ipv6_pinfo_offset; 1321 slab_flags_t slab_flags; 1322 unsigned int useroffset; /* Usercopy region offset */ 1323 unsigned int usersize; /* Usercopy region size */ 1324 1325 unsigned int __percpu *orphan_count; 1326 1327 struct request_sock_ops *rsk_prot; 1328 struct timewait_sock_ops *twsk_prot; 1329 1330 union { 1331 struct inet_hashinfo *hashinfo; 1332 struct udp_table *udp_table; 1333 struct raw_hashinfo *raw_hash; 1334 struct smc_hashinfo *smc_hash; 1335 } h; 1336 1337 struct module *owner; 1338 1339 char name[32]; 1340 1341 struct list_head node; 1342 int (*diag_destroy)(struct sock *sk, int err); 1343 } __randomize_layout; 1344 1345 int proto_register(struct proto *prot, int alloc_slab); 1346 void proto_unregister(struct proto *prot); 1347 int sock_load_diag_module(int family, int protocol); 1348 1349 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1350 1351 static inline int sk_forward_alloc_get(const struct sock *sk) 1352 { 1353 #if IS_ENABLED(CONFIG_MPTCP) 1354 if (sk->sk_prot->forward_alloc_get) 1355 return sk->sk_prot->forward_alloc_get(sk); 1356 #endif 1357 return READ_ONCE(sk->sk_forward_alloc); 1358 } 1359 1360 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1361 { 1362 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1363 return false; 1364 1365 return sk->sk_prot->stream_memory_free ? 1366 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free, 1367 tcp_stream_memory_free, sk, wake) : true; 1368 } 1369 1370 static inline bool sk_stream_memory_free(const struct sock *sk) 1371 { 1372 return __sk_stream_memory_free(sk, 0); 1373 } 1374 1375 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1376 { 1377 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1378 __sk_stream_memory_free(sk, wake); 1379 } 1380 1381 static inline bool sk_stream_is_writeable(const struct sock *sk) 1382 { 1383 return __sk_stream_is_writeable(sk, 0); 1384 } 1385 1386 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1387 struct cgroup *ancestor) 1388 { 1389 #ifdef CONFIG_SOCK_CGROUP_DATA 1390 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1391 ancestor); 1392 #else 1393 return -ENOTSUPP; 1394 #endif 1395 } 1396 1397 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1398 1399 static inline void sk_sockets_allocated_dec(struct sock *sk) 1400 { 1401 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1402 SK_ALLOC_PERCPU_COUNTER_BATCH); 1403 } 1404 1405 static inline void sk_sockets_allocated_inc(struct sock *sk) 1406 { 1407 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1408 SK_ALLOC_PERCPU_COUNTER_BATCH); 1409 } 1410 1411 static inline u64 1412 sk_sockets_allocated_read_positive(struct sock *sk) 1413 { 1414 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1415 } 1416 1417 static inline int 1418 proto_sockets_allocated_sum_positive(struct proto *prot) 1419 { 1420 return percpu_counter_sum_positive(prot->sockets_allocated); 1421 } 1422 1423 #ifdef CONFIG_PROC_FS 1424 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 1425 struct prot_inuse { 1426 int all; 1427 int val[PROTO_INUSE_NR]; 1428 }; 1429 1430 static inline void sock_prot_inuse_add(const struct net *net, 1431 const struct proto *prot, int val) 1432 { 1433 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 1434 } 1435 1436 static inline void sock_inuse_add(const struct net *net, int val) 1437 { 1438 this_cpu_add(net->core.prot_inuse->all, val); 1439 } 1440 1441 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1442 int sock_inuse_get(struct net *net); 1443 #else 1444 static inline void sock_prot_inuse_add(const struct net *net, 1445 const struct proto *prot, int val) 1446 { 1447 } 1448 1449 static inline void sock_inuse_add(const struct net *net, int val) 1450 { 1451 } 1452 #endif 1453 1454 1455 /* With per-bucket locks this operation is not-atomic, so that 1456 * this version is not worse. 1457 */ 1458 static inline int __sk_prot_rehash(struct sock *sk) 1459 { 1460 sk->sk_prot->unhash(sk); 1461 return sk->sk_prot->hash(sk); 1462 } 1463 1464 /* About 10 seconds */ 1465 #define SOCK_DESTROY_TIME (10*HZ) 1466 1467 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1468 #define PROT_SOCK 1024 1469 1470 #define SHUTDOWN_MASK 3 1471 #define RCV_SHUTDOWN 1 1472 #define SEND_SHUTDOWN 2 1473 1474 #define SOCK_BINDADDR_LOCK 4 1475 #define SOCK_BINDPORT_LOCK 8 1476 1477 struct socket_alloc { 1478 struct socket socket; 1479 struct inode vfs_inode; 1480 }; 1481 1482 static inline struct socket *SOCKET_I(struct inode *inode) 1483 { 1484 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1485 } 1486 1487 static inline struct inode *SOCK_INODE(struct socket *socket) 1488 { 1489 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1490 } 1491 1492 /* 1493 * Functions for memory accounting 1494 */ 1495 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1496 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1497 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1498 void __sk_mem_reclaim(struct sock *sk, int amount); 1499 1500 #define SK_MEM_SEND 0 1501 #define SK_MEM_RECV 1 1502 1503 /* sysctl_mem values are in pages */ 1504 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1505 { 1506 return READ_ONCE(sk->sk_prot->sysctl_mem[index]); 1507 } 1508 1509 static inline int sk_mem_pages(int amt) 1510 { 1511 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT; 1512 } 1513 1514 static inline bool sk_has_account(struct sock *sk) 1515 { 1516 /* return true if protocol supports memory accounting */ 1517 return !!sk->sk_prot->memory_allocated; 1518 } 1519 1520 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1521 { 1522 int delta; 1523 1524 if (!sk_has_account(sk)) 1525 return true; 1526 delta = size - sk->sk_forward_alloc; 1527 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND); 1528 } 1529 1530 static inline bool 1531 __sk_rmem_schedule(struct sock *sk, int size, bool pfmemalloc) 1532 { 1533 int delta; 1534 1535 if (!sk_has_account(sk)) 1536 return true; 1537 delta = size - sk->sk_forward_alloc; 1538 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) || 1539 pfmemalloc; 1540 } 1541 1542 static inline bool 1543 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1544 { 1545 return __sk_rmem_schedule(sk, size, skb_pfmemalloc(skb)); 1546 } 1547 1548 static inline int sk_unused_reserved_mem(const struct sock *sk) 1549 { 1550 int unused_mem; 1551 1552 if (likely(!sk->sk_reserved_mem)) 1553 return 0; 1554 1555 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued - 1556 atomic_read(&sk->sk_rmem_alloc); 1557 1558 return unused_mem > 0 ? unused_mem : 0; 1559 } 1560 1561 static inline void sk_mem_reclaim(struct sock *sk) 1562 { 1563 int reclaimable; 1564 1565 if (!sk_has_account(sk)) 1566 return; 1567 1568 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk); 1569 1570 if (reclaimable >= (int)PAGE_SIZE) 1571 __sk_mem_reclaim(sk, reclaimable); 1572 } 1573 1574 static inline void sk_mem_reclaim_final(struct sock *sk) 1575 { 1576 sk->sk_reserved_mem = 0; 1577 sk_mem_reclaim(sk); 1578 } 1579 1580 static inline void sk_mem_charge(struct sock *sk, int size) 1581 { 1582 if (!sk_has_account(sk)) 1583 return; 1584 sk_forward_alloc_add(sk, -size); 1585 } 1586 1587 static inline void sk_mem_uncharge(struct sock *sk, int size) 1588 { 1589 if (!sk_has_account(sk)) 1590 return; 1591 sk_forward_alloc_add(sk, size); 1592 sk_mem_reclaim(sk); 1593 } 1594 1595 /* 1596 * Macro so as to not evaluate some arguments when 1597 * lockdep is not enabled. 1598 * 1599 * Mark both the sk_lock and the sk_lock.slock as a 1600 * per-address-family lock class. 1601 */ 1602 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1603 do { \ 1604 sk->sk_lock.owned = 0; \ 1605 init_waitqueue_head(&sk->sk_lock.wq); \ 1606 spin_lock_init(&(sk)->sk_lock.slock); \ 1607 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1608 sizeof((sk)->sk_lock)); \ 1609 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1610 (skey), (sname)); \ 1611 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1612 } while (0) 1613 1614 static inline bool lockdep_sock_is_held(const struct sock *sk) 1615 { 1616 return lockdep_is_held(&sk->sk_lock) || 1617 lockdep_is_held(&sk->sk_lock.slock); 1618 } 1619 1620 void lock_sock_nested(struct sock *sk, int subclass); 1621 1622 static inline void lock_sock(struct sock *sk) 1623 { 1624 lock_sock_nested(sk, 0); 1625 } 1626 1627 void __lock_sock(struct sock *sk); 1628 void __release_sock(struct sock *sk); 1629 void release_sock(struct sock *sk); 1630 1631 /* BH context may only use the following locking interface. */ 1632 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1633 #define bh_lock_sock_nested(__sk) \ 1634 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1635 SINGLE_DEPTH_NESTING) 1636 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1637 1638 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1639 1640 /** 1641 * lock_sock_fast - fast version of lock_sock 1642 * @sk: socket 1643 * 1644 * This version should be used for very small section, where process won't block 1645 * return false if fast path is taken: 1646 * 1647 * sk_lock.slock locked, owned = 0, BH disabled 1648 * 1649 * return true if slow path is taken: 1650 * 1651 * sk_lock.slock unlocked, owned = 1, BH enabled 1652 */ 1653 static inline bool lock_sock_fast(struct sock *sk) 1654 { 1655 /* The sk_lock has mutex_lock() semantics here. */ 1656 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 1657 1658 return __lock_sock_fast(sk); 1659 } 1660 1661 /* fast socket lock variant for caller already holding a [different] socket lock */ 1662 static inline bool lock_sock_fast_nested(struct sock *sk) 1663 { 1664 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_); 1665 1666 return __lock_sock_fast(sk); 1667 } 1668 1669 /** 1670 * unlock_sock_fast - complement of lock_sock_fast 1671 * @sk: socket 1672 * @slow: slow mode 1673 * 1674 * fast unlock socket for user context. 1675 * If slow mode is on, we call regular release_sock() 1676 */ 1677 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1678 __releases(&sk->sk_lock.slock) 1679 { 1680 if (slow) { 1681 release_sock(sk); 1682 __release(&sk->sk_lock.slock); 1683 } else { 1684 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1685 spin_unlock_bh(&sk->sk_lock.slock); 1686 } 1687 } 1688 1689 void sockopt_lock_sock(struct sock *sk); 1690 void sockopt_release_sock(struct sock *sk); 1691 bool sockopt_ns_capable(struct user_namespace *ns, int cap); 1692 bool sockopt_capable(int cap); 1693 1694 /* Used by processes to "lock" a socket state, so that 1695 * interrupts and bottom half handlers won't change it 1696 * from under us. It essentially blocks any incoming 1697 * packets, so that we won't get any new data or any 1698 * packets that change the state of the socket. 1699 * 1700 * While locked, BH processing will add new packets to 1701 * the backlog queue. This queue is processed by the 1702 * owner of the socket lock right before it is released. 1703 * 1704 * Since ~2.3.5 it is also exclusive sleep lock serializing 1705 * accesses from user process context. 1706 */ 1707 1708 static inline void sock_owned_by_me(const struct sock *sk) 1709 { 1710 #ifdef CONFIG_LOCKDEP 1711 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1712 #endif 1713 } 1714 1715 static inline void sock_not_owned_by_me(const struct sock *sk) 1716 { 1717 #ifdef CONFIG_LOCKDEP 1718 WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks); 1719 #endif 1720 } 1721 1722 static inline bool sock_owned_by_user(const struct sock *sk) 1723 { 1724 sock_owned_by_me(sk); 1725 return sk->sk_lock.owned; 1726 } 1727 1728 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1729 { 1730 return sk->sk_lock.owned; 1731 } 1732 1733 static inline void sock_release_ownership(struct sock *sk) 1734 { 1735 DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk)); 1736 sk->sk_lock.owned = 0; 1737 1738 /* The sk_lock has mutex_unlock() semantics: */ 1739 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1740 } 1741 1742 /* no reclassification while locks are held */ 1743 static inline bool sock_allow_reclassification(const struct sock *csk) 1744 { 1745 struct sock *sk = (struct sock *)csk; 1746 1747 return !sock_owned_by_user_nocheck(sk) && 1748 !spin_is_locked(&sk->sk_lock.slock); 1749 } 1750 1751 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1752 struct proto *prot, int kern); 1753 void sk_free(struct sock *sk); 1754 void sk_destruct(struct sock *sk); 1755 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1756 void sk_free_unlock_clone(struct sock *sk); 1757 1758 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1759 gfp_t priority); 1760 void __sock_wfree(struct sk_buff *skb); 1761 void sock_wfree(struct sk_buff *skb); 1762 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1763 gfp_t priority); 1764 void skb_orphan_partial(struct sk_buff *skb); 1765 void sock_rfree(struct sk_buff *skb); 1766 void sock_efree(struct sk_buff *skb); 1767 #ifdef CONFIG_INET 1768 void sock_edemux(struct sk_buff *skb); 1769 void sock_pfree(struct sk_buff *skb); 1770 1771 static inline void skb_set_owner_edemux(struct sk_buff *skb, struct sock *sk) 1772 { 1773 skb_orphan(skb); 1774 if (refcount_inc_not_zero(&sk->sk_refcnt)) { 1775 skb->sk = sk; 1776 skb->destructor = sock_edemux; 1777 } 1778 } 1779 #else 1780 #define sock_edemux sock_efree 1781 #endif 1782 1783 int sk_setsockopt(struct sock *sk, int level, int optname, 1784 sockptr_t optval, unsigned int optlen); 1785 int sock_setsockopt(struct socket *sock, int level, int op, 1786 sockptr_t optval, unsigned int optlen); 1787 int do_sock_setsockopt(struct socket *sock, bool compat, int level, 1788 int optname, sockptr_t optval, int optlen); 1789 int do_sock_getsockopt(struct socket *sock, bool compat, int level, 1790 int optname, sockptr_t optval, sockptr_t optlen); 1791 1792 int sk_getsockopt(struct sock *sk, int level, int optname, 1793 sockptr_t optval, sockptr_t optlen); 1794 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1795 bool timeval, bool time32); 1796 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1797 unsigned long data_len, int noblock, 1798 int *errcode, int max_page_order); 1799 1800 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1801 unsigned long size, 1802 int noblock, int *errcode) 1803 { 1804 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1805 } 1806 1807 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1808 void sock_kfree_s(struct sock *sk, void *mem, int size); 1809 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1810 void sk_send_sigurg(struct sock *sk); 1811 1812 static inline void sock_replace_proto(struct sock *sk, struct proto *proto) 1813 { 1814 if (sk->sk_socket) 1815 clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1816 WRITE_ONCE(sk->sk_prot, proto); 1817 } 1818 1819 struct sockcm_cookie { 1820 u64 transmit_time; 1821 u32 mark; 1822 u32 tsflags; 1823 u32 ts_opt_id; 1824 u32 priority; 1825 }; 1826 1827 static inline void sockcm_init(struct sockcm_cookie *sockc, 1828 const struct sock *sk) 1829 { 1830 *sockc = (struct sockcm_cookie) { 1831 .tsflags = READ_ONCE(sk->sk_tsflags), 1832 .priority = READ_ONCE(sk->sk_priority), 1833 }; 1834 } 1835 1836 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 1837 struct sockcm_cookie *sockc); 1838 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1839 struct sockcm_cookie *sockc); 1840 1841 /* 1842 * Functions to fill in entries in struct proto_ops when a protocol 1843 * does not implement a particular function. 1844 */ 1845 int sock_no_bind(struct socket *, struct sockaddr *, int); 1846 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1847 int sock_no_socketpair(struct socket *, struct socket *); 1848 int sock_no_accept(struct socket *, struct socket *, struct proto_accept_arg *); 1849 int sock_no_getname(struct socket *, struct sockaddr *, int); 1850 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1851 int sock_no_listen(struct socket *, int); 1852 int sock_no_shutdown(struct socket *, int); 1853 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1854 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1855 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1856 int sock_no_mmap(struct file *file, struct socket *sock, 1857 struct vm_area_struct *vma); 1858 1859 /* 1860 * Functions to fill in entries in struct proto_ops when a protocol 1861 * uses the inet style. 1862 */ 1863 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1864 char __user *optval, int __user *optlen); 1865 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1866 int flags); 1867 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1868 sockptr_t optval, unsigned int optlen); 1869 1870 void sk_common_release(struct sock *sk); 1871 1872 /* 1873 * Default socket callbacks and setup code 1874 */ 1875 1876 /* Initialise core socket variables using an explicit uid. */ 1877 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid); 1878 1879 /* Initialise core socket variables. 1880 * Assumes struct socket *sock is embedded in a struct socket_alloc. 1881 */ 1882 void sock_init_data(struct socket *sock, struct sock *sk); 1883 1884 /* 1885 * Socket reference counting postulates. 1886 * 1887 * * Each user of socket SHOULD hold a reference count. 1888 * * Each access point to socket (an hash table bucket, reference from a list, 1889 * running timer, skb in flight MUST hold a reference count. 1890 * * When reference count hits 0, it means it will never increase back. 1891 * * When reference count hits 0, it means that no references from 1892 * outside exist to this socket and current process on current CPU 1893 * is last user and may/should destroy this socket. 1894 * * sk_free is called from any context: process, BH, IRQ. When 1895 * it is called, socket has no references from outside -> sk_free 1896 * may release descendant resources allocated by the socket, but 1897 * to the time when it is called, socket is NOT referenced by any 1898 * hash tables, lists etc. 1899 * * Packets, delivered from outside (from network or from another process) 1900 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1901 * when they sit in queue. Otherwise, packets will leak to hole, when 1902 * socket is looked up by one cpu and unhasing is made by another CPU. 1903 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1904 * (leak to backlog). Packet socket does all the processing inside 1905 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1906 * use separate SMP lock, so that they are prone too. 1907 */ 1908 1909 /* Ungrab socket and destroy it, if it was the last reference. */ 1910 static inline void sock_put(struct sock *sk) 1911 { 1912 if (refcount_dec_and_test(&sk->sk_refcnt)) 1913 sk_free(sk); 1914 } 1915 /* Generic version of sock_put(), dealing with all sockets 1916 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1917 */ 1918 void sock_gen_put(struct sock *sk); 1919 1920 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1921 unsigned int trim_cap, bool refcounted); 1922 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1923 const int nested) 1924 { 1925 return __sk_receive_skb(sk, skb, nested, 1, true); 1926 } 1927 1928 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1929 { 1930 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1931 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1932 return; 1933 /* Paired with READ_ONCE() in sk_tx_queue_get() and 1934 * other WRITE_ONCE() because socket lock might be not held. 1935 */ 1936 WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue); 1937 } 1938 1939 #define NO_QUEUE_MAPPING USHRT_MAX 1940 1941 static inline void sk_tx_queue_clear(struct sock *sk) 1942 { 1943 /* Paired with READ_ONCE() in sk_tx_queue_get() and 1944 * other WRITE_ONCE() because socket lock might be not held. 1945 */ 1946 WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING); 1947 } 1948 1949 static inline int sk_tx_queue_get(const struct sock *sk) 1950 { 1951 if (sk) { 1952 /* Paired with WRITE_ONCE() in sk_tx_queue_clear() 1953 * and sk_tx_queue_set(). 1954 */ 1955 int val = READ_ONCE(sk->sk_tx_queue_mapping); 1956 1957 if (val != NO_QUEUE_MAPPING) 1958 return val; 1959 } 1960 return -1; 1961 } 1962 1963 static inline void __sk_rx_queue_set(struct sock *sk, 1964 const struct sk_buff *skb, 1965 bool force_set) 1966 { 1967 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1968 if (skb_rx_queue_recorded(skb)) { 1969 u16 rx_queue = skb_get_rx_queue(skb); 1970 1971 if (force_set || 1972 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) 1973 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue); 1974 } 1975 #endif 1976 } 1977 1978 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1979 { 1980 __sk_rx_queue_set(sk, skb, true); 1981 } 1982 1983 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb) 1984 { 1985 __sk_rx_queue_set(sk, skb, false); 1986 } 1987 1988 static inline void sk_rx_queue_clear(struct sock *sk) 1989 { 1990 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1991 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING); 1992 #endif 1993 } 1994 1995 static inline int sk_rx_queue_get(const struct sock *sk) 1996 { 1997 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1998 if (sk) { 1999 int res = READ_ONCE(sk->sk_rx_queue_mapping); 2000 2001 if (res != NO_QUEUE_MAPPING) 2002 return res; 2003 } 2004 #endif 2005 2006 return -1; 2007 } 2008 2009 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 2010 { 2011 sk->sk_socket = sock; 2012 } 2013 2014 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 2015 { 2016 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 2017 return &rcu_dereference_raw(sk->sk_wq)->wait; 2018 } 2019 /* Detach socket from process context. 2020 * Announce socket dead, detach it from wait queue and inode. 2021 * Note that parent inode held reference count on this struct sock, 2022 * we do not release it in this function, because protocol 2023 * probably wants some additional cleanups or even continuing 2024 * to work with this socket (TCP). 2025 */ 2026 static inline void sock_orphan(struct sock *sk) 2027 { 2028 write_lock_bh(&sk->sk_callback_lock); 2029 sock_set_flag(sk, SOCK_DEAD); 2030 sk_set_socket(sk, NULL); 2031 sk->sk_wq = NULL; 2032 write_unlock_bh(&sk->sk_callback_lock); 2033 } 2034 2035 static inline void sock_graft(struct sock *sk, struct socket *parent) 2036 { 2037 WARN_ON(parent->sk); 2038 write_lock_bh(&sk->sk_callback_lock); 2039 rcu_assign_pointer(sk->sk_wq, &parent->wq); 2040 parent->sk = sk; 2041 sk_set_socket(sk, parent); 2042 sk->sk_uid = SOCK_INODE(parent)->i_uid; 2043 security_sock_graft(sk, parent); 2044 write_unlock_bh(&sk->sk_callback_lock); 2045 } 2046 2047 kuid_t sock_i_uid(struct sock *sk); 2048 unsigned long __sock_i_ino(struct sock *sk); 2049 unsigned long sock_i_ino(struct sock *sk); 2050 2051 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 2052 { 2053 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 2054 } 2055 2056 static inline u32 net_tx_rndhash(void) 2057 { 2058 u32 v = get_random_u32(); 2059 2060 return v ?: 1; 2061 } 2062 2063 static inline void sk_set_txhash(struct sock *sk) 2064 { 2065 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */ 2066 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash()); 2067 } 2068 2069 static inline bool sk_rethink_txhash(struct sock *sk) 2070 { 2071 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) { 2072 sk_set_txhash(sk); 2073 return true; 2074 } 2075 return false; 2076 } 2077 2078 static inline struct dst_entry * 2079 __sk_dst_get(const struct sock *sk) 2080 { 2081 return rcu_dereference_check(sk->sk_dst_cache, 2082 lockdep_sock_is_held(sk)); 2083 } 2084 2085 static inline struct dst_entry * 2086 sk_dst_get(const struct sock *sk) 2087 { 2088 struct dst_entry *dst; 2089 2090 rcu_read_lock(); 2091 dst = rcu_dereference(sk->sk_dst_cache); 2092 if (dst && !rcuref_get(&dst->__rcuref)) 2093 dst = NULL; 2094 rcu_read_unlock(); 2095 return dst; 2096 } 2097 2098 static inline void __dst_negative_advice(struct sock *sk) 2099 { 2100 struct dst_entry *dst = __sk_dst_get(sk); 2101 2102 if (dst && dst->ops->negative_advice) 2103 dst->ops->negative_advice(sk, dst); 2104 } 2105 2106 static inline void dst_negative_advice(struct sock *sk) 2107 { 2108 sk_rethink_txhash(sk); 2109 __dst_negative_advice(sk); 2110 } 2111 2112 static inline void 2113 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 2114 { 2115 struct dst_entry *old_dst; 2116 2117 sk_tx_queue_clear(sk); 2118 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2119 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 2120 lockdep_sock_is_held(sk)); 2121 rcu_assign_pointer(sk->sk_dst_cache, dst); 2122 dst_release(old_dst); 2123 } 2124 2125 static inline void 2126 sk_dst_set(struct sock *sk, struct dst_entry *dst) 2127 { 2128 struct dst_entry *old_dst; 2129 2130 sk_tx_queue_clear(sk); 2131 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2132 old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst))); 2133 dst_release(old_dst); 2134 } 2135 2136 static inline void 2137 __sk_dst_reset(struct sock *sk) 2138 { 2139 __sk_dst_set(sk, NULL); 2140 } 2141 2142 static inline void 2143 sk_dst_reset(struct sock *sk) 2144 { 2145 sk_dst_set(sk, NULL); 2146 } 2147 2148 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2149 2150 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2151 2152 static inline void sk_dst_confirm(struct sock *sk) 2153 { 2154 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2155 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2156 } 2157 2158 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2159 { 2160 if (skb_get_dst_pending_confirm(skb)) { 2161 struct sock *sk = skb->sk; 2162 2163 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2164 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2165 neigh_confirm(n); 2166 } 2167 } 2168 2169 bool sk_mc_loop(const struct sock *sk); 2170 2171 static inline bool sk_can_gso(const struct sock *sk) 2172 { 2173 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2174 } 2175 2176 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2177 2178 static inline void sk_gso_disable(struct sock *sk) 2179 { 2180 sk->sk_gso_disabled = 1; 2181 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2182 } 2183 2184 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2185 struct iov_iter *from, char *to, 2186 int copy, int offset) 2187 { 2188 if (skb->ip_summed == CHECKSUM_NONE) { 2189 __wsum csum = 0; 2190 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2191 return -EFAULT; 2192 skb->csum = csum_block_add(skb->csum, csum, offset); 2193 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2194 if (!copy_from_iter_full_nocache(to, copy, from)) 2195 return -EFAULT; 2196 } else if (!copy_from_iter_full(to, copy, from)) 2197 return -EFAULT; 2198 2199 return 0; 2200 } 2201 2202 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2203 struct iov_iter *from, int copy) 2204 { 2205 int err, offset = skb->len; 2206 2207 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2208 copy, offset); 2209 if (err) 2210 __skb_trim(skb, offset); 2211 2212 return err; 2213 } 2214 2215 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2216 struct sk_buff *skb, 2217 struct page *page, 2218 int off, int copy) 2219 { 2220 int err; 2221 2222 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2223 copy, skb->len); 2224 if (err) 2225 return err; 2226 2227 skb_len_add(skb, copy); 2228 sk_wmem_queued_add(sk, copy); 2229 sk_mem_charge(sk, copy); 2230 return 0; 2231 } 2232 2233 /** 2234 * sk_wmem_alloc_get - returns write allocations 2235 * @sk: socket 2236 * 2237 * Return: sk_wmem_alloc minus initial offset of one 2238 */ 2239 static inline int sk_wmem_alloc_get(const struct sock *sk) 2240 { 2241 return refcount_read(&sk->sk_wmem_alloc) - 1; 2242 } 2243 2244 /** 2245 * sk_rmem_alloc_get - returns read allocations 2246 * @sk: socket 2247 * 2248 * Return: sk_rmem_alloc 2249 */ 2250 static inline int sk_rmem_alloc_get(const struct sock *sk) 2251 { 2252 return atomic_read(&sk->sk_rmem_alloc); 2253 } 2254 2255 /** 2256 * sk_has_allocations - check if allocations are outstanding 2257 * @sk: socket 2258 * 2259 * Return: true if socket has write or read allocations 2260 */ 2261 static inline bool sk_has_allocations(const struct sock *sk) 2262 { 2263 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2264 } 2265 2266 /** 2267 * skwq_has_sleeper - check if there are any waiting processes 2268 * @wq: struct socket_wq 2269 * 2270 * Return: true if socket_wq has waiting processes 2271 * 2272 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2273 * barrier call. They were added due to the race found within the tcp code. 2274 * 2275 * Consider following tcp code paths:: 2276 * 2277 * CPU1 CPU2 2278 * sys_select receive packet 2279 * ... ... 2280 * __add_wait_queue update tp->rcv_nxt 2281 * ... ... 2282 * tp->rcv_nxt check sock_def_readable 2283 * ... { 2284 * schedule rcu_read_lock(); 2285 * wq = rcu_dereference(sk->sk_wq); 2286 * if (wq && waitqueue_active(&wq->wait)) 2287 * wake_up_interruptible(&wq->wait) 2288 * ... 2289 * } 2290 * 2291 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2292 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2293 * could then endup calling schedule and sleep forever if there are no more 2294 * data on the socket. 2295 * 2296 */ 2297 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2298 { 2299 return wq && wq_has_sleeper(&wq->wait); 2300 } 2301 2302 /** 2303 * sock_poll_wait - wrapper for the poll_wait call. 2304 * @filp: file 2305 * @sock: socket to wait on 2306 * @p: poll_table 2307 * 2308 * See the comments in the wq_has_sleeper function. 2309 */ 2310 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2311 poll_table *p) 2312 { 2313 /* Provides a barrier we need to be sure we are in sync 2314 * with the socket flags modification. 2315 * 2316 * This memory barrier is paired in the wq_has_sleeper. 2317 */ 2318 poll_wait(filp, &sock->wq.wait, p); 2319 } 2320 2321 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2322 { 2323 /* This pairs with WRITE_ONCE() in sk_set_txhash() */ 2324 u32 txhash = READ_ONCE(sk->sk_txhash); 2325 2326 if (txhash) { 2327 skb->l4_hash = 1; 2328 skb->hash = txhash; 2329 } 2330 } 2331 2332 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2333 2334 /* 2335 * Queue a received datagram if it will fit. Stream and sequenced 2336 * protocols can't normally use this as they need to fit buffers in 2337 * and play with them. 2338 * 2339 * Inlined as it's very short and called for pretty much every 2340 * packet ever received. 2341 */ 2342 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2343 { 2344 skb_orphan(skb); 2345 skb->sk = sk; 2346 skb->destructor = sock_rfree; 2347 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2348 sk_mem_charge(sk, skb->truesize); 2349 } 2350 2351 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2352 { 2353 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2354 skb_orphan(skb); 2355 skb->destructor = sock_efree; 2356 skb->sk = sk; 2357 return true; 2358 } 2359 return false; 2360 } 2361 2362 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) 2363 { 2364 skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 2365 if (skb) { 2366 if (sk_rmem_schedule(sk, skb, skb->truesize)) { 2367 skb_set_owner_r(skb, sk); 2368 return skb; 2369 } 2370 __kfree_skb(skb); 2371 } 2372 return NULL; 2373 } 2374 2375 static inline void skb_prepare_for_gro(struct sk_buff *skb) 2376 { 2377 if (skb->destructor != sock_wfree) { 2378 skb_orphan(skb); 2379 return; 2380 } 2381 skb->slow_gro = 1; 2382 } 2383 2384 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2385 unsigned long expires); 2386 2387 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2388 2389 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2390 2391 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2392 struct sk_buff *skb, unsigned int flags, 2393 void (*destructor)(struct sock *sk, 2394 struct sk_buff *skb)); 2395 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2396 2397 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 2398 enum skb_drop_reason *reason); 2399 2400 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 2401 { 2402 return sock_queue_rcv_skb_reason(sk, skb, NULL); 2403 } 2404 2405 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2406 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2407 2408 /* 2409 * Recover an error report and clear atomically 2410 */ 2411 2412 static inline int sock_error(struct sock *sk) 2413 { 2414 int err; 2415 2416 /* Avoid an atomic operation for the common case. 2417 * This is racy since another cpu/thread can change sk_err under us. 2418 */ 2419 if (likely(data_race(!sk->sk_err))) 2420 return 0; 2421 2422 err = xchg(&sk->sk_err, 0); 2423 return -err; 2424 } 2425 2426 void sk_error_report(struct sock *sk); 2427 2428 static inline unsigned long sock_wspace(struct sock *sk) 2429 { 2430 int amt = 0; 2431 2432 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2433 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2434 if (amt < 0) 2435 amt = 0; 2436 } 2437 return amt; 2438 } 2439 2440 /* Note: 2441 * We use sk->sk_wq_raw, from contexts knowing this 2442 * pointer is not NULL and cannot disappear/change. 2443 */ 2444 static inline void sk_set_bit(int nr, struct sock *sk) 2445 { 2446 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2447 !sock_flag(sk, SOCK_FASYNC)) 2448 return; 2449 2450 set_bit(nr, &sk->sk_wq_raw->flags); 2451 } 2452 2453 static inline void sk_clear_bit(int nr, struct sock *sk) 2454 { 2455 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2456 !sock_flag(sk, SOCK_FASYNC)) 2457 return; 2458 2459 clear_bit(nr, &sk->sk_wq_raw->flags); 2460 } 2461 2462 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2463 { 2464 if (sock_flag(sk, SOCK_FASYNC)) { 2465 rcu_read_lock(); 2466 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2467 rcu_read_unlock(); 2468 } 2469 } 2470 2471 static inline void sk_wake_async_rcu(const struct sock *sk, int how, int band) 2472 { 2473 if (unlikely(sock_flag(sk, SOCK_FASYNC))) 2474 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2475 } 2476 2477 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2478 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2479 * Note: for send buffers, TCP works better if we can build two skbs at 2480 * minimum. 2481 */ 2482 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2483 2484 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2485 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2486 2487 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2488 { 2489 u32 val; 2490 2491 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2492 return; 2493 2494 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2495 val = max_t(u32, val, sk_unused_reserved_mem(sk)); 2496 2497 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2498 } 2499 2500 /** 2501 * sk_page_frag - return an appropriate page_frag 2502 * @sk: socket 2503 * 2504 * Use the per task page_frag instead of the per socket one for 2505 * optimization when we know that we're in process context and own 2506 * everything that's associated with %current. 2507 * 2508 * Both direct reclaim and page faults can nest inside other 2509 * socket operations and end up recursing into sk_page_frag() 2510 * while it's already in use: explicitly avoid task page_frag 2511 * when users disable sk_use_task_frag. 2512 * 2513 * Return: a per task page_frag if context allows that, 2514 * otherwise a per socket one. 2515 */ 2516 static inline struct page_frag *sk_page_frag(struct sock *sk) 2517 { 2518 if (sk->sk_use_task_frag) 2519 return ¤t->task_frag; 2520 2521 return &sk->sk_frag; 2522 } 2523 2524 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2525 2526 /* 2527 * Default write policy as shown to user space via poll/select/SIGIO 2528 */ 2529 static inline bool sock_writeable(const struct sock *sk) 2530 { 2531 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2532 } 2533 2534 static inline gfp_t gfp_any(void) 2535 { 2536 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2537 } 2538 2539 static inline gfp_t gfp_memcg_charge(void) 2540 { 2541 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2542 } 2543 2544 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2545 { 2546 return noblock ? 0 : sk->sk_rcvtimeo; 2547 } 2548 2549 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2550 { 2551 return noblock ? 0 : sk->sk_sndtimeo; 2552 } 2553 2554 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2555 { 2556 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2557 2558 return v ?: 1; 2559 } 2560 2561 /* Alas, with timeout socket operations are not restartable. 2562 * Compare this to poll(). 2563 */ 2564 static inline int sock_intr_errno(long timeo) 2565 { 2566 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2567 } 2568 2569 struct sock_skb_cb { 2570 u32 dropcount; 2571 }; 2572 2573 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2574 * using skb->cb[] would keep using it directly and utilize its 2575 * alignment guarantee. 2576 */ 2577 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2578 sizeof(struct sock_skb_cb))) 2579 2580 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2581 SOCK_SKB_CB_OFFSET)) 2582 2583 #define sock_skb_cb_check_size(size) \ 2584 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2585 2586 static inline void 2587 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2588 { 2589 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2590 atomic_read(&sk->sk_drops) : 0; 2591 } 2592 2593 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2594 { 2595 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2596 2597 atomic_add(segs, &sk->sk_drops); 2598 } 2599 2600 static inline ktime_t sock_read_timestamp(struct sock *sk) 2601 { 2602 #if BITS_PER_LONG==32 2603 unsigned int seq; 2604 ktime_t kt; 2605 2606 do { 2607 seq = read_seqbegin(&sk->sk_stamp_seq); 2608 kt = sk->sk_stamp; 2609 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2610 2611 return kt; 2612 #else 2613 return READ_ONCE(sk->sk_stamp); 2614 #endif 2615 } 2616 2617 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2618 { 2619 #if BITS_PER_LONG==32 2620 write_seqlock(&sk->sk_stamp_seq); 2621 sk->sk_stamp = kt; 2622 write_sequnlock(&sk->sk_stamp_seq); 2623 #else 2624 WRITE_ONCE(sk->sk_stamp, kt); 2625 #endif 2626 } 2627 2628 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2629 struct sk_buff *skb); 2630 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2631 struct sk_buff *skb); 2632 2633 static inline void 2634 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2635 { 2636 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2637 u32 tsflags = READ_ONCE(sk->sk_tsflags); 2638 ktime_t kt = skb->tstamp; 2639 /* 2640 * generate control messages if 2641 * - receive time stamping in software requested 2642 * - software time stamp available and wanted 2643 * - hardware time stamps available and wanted 2644 */ 2645 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2646 (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2647 (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2648 (hwtstamps->hwtstamp && 2649 (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2650 __sock_recv_timestamp(msg, sk, skb); 2651 else 2652 sock_write_timestamp(sk, kt); 2653 2654 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb)) 2655 __sock_recv_wifi_status(msg, sk, skb); 2656 } 2657 2658 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2659 struct sk_buff *skb); 2660 2661 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2662 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2663 struct sk_buff *skb) 2664 { 2665 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \ 2666 (1UL << SOCK_RCVTSTAMP) | \ 2667 (1UL << SOCK_RCVMARK) |\ 2668 (1UL << SOCK_RCVPRIORITY)) 2669 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2670 SOF_TIMESTAMPING_RAW_HARDWARE) 2671 2672 if (sk->sk_flags & FLAGS_RECV_CMSGS || 2673 READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY) 2674 __sock_recv_cmsgs(msg, sk, skb); 2675 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2676 sock_write_timestamp(sk, skb->tstamp); 2677 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP)) 2678 sock_write_timestamp(sk, 0); 2679 } 2680 2681 void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags); 2682 2683 /** 2684 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2685 * @sk: socket sending this packet 2686 * @sockc: pointer to socket cmsg cookie to get timestamping info 2687 * @tx_flags: completed with instructions for time stamping 2688 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2689 * 2690 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2691 */ 2692 static inline void _sock_tx_timestamp(struct sock *sk, 2693 const struct sockcm_cookie *sockc, 2694 __u8 *tx_flags, __u32 *tskey) 2695 { 2696 __u32 tsflags = sockc->tsflags; 2697 2698 if (unlikely(tsflags)) { 2699 __sock_tx_timestamp(tsflags, tx_flags); 2700 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2701 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) { 2702 if (tsflags & SOCKCM_FLAG_TS_OPT_ID) 2703 *tskey = sockc->ts_opt_id; 2704 else 2705 *tskey = atomic_inc_return(&sk->sk_tskey) - 1; 2706 } 2707 } 2708 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2709 *tx_flags |= SKBTX_WIFI_STATUS; 2710 } 2711 2712 static inline void sock_tx_timestamp(struct sock *sk, 2713 const struct sockcm_cookie *sockc, 2714 __u8 *tx_flags) 2715 { 2716 _sock_tx_timestamp(sk, sockc, tx_flags, NULL); 2717 } 2718 2719 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, 2720 const struct sockcm_cookie *sockc) 2721 { 2722 _sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags, 2723 &skb_shinfo(skb)->tskey); 2724 } 2725 2726 static inline bool sk_is_inet(const struct sock *sk) 2727 { 2728 int family = READ_ONCE(sk->sk_family); 2729 2730 return family == AF_INET || family == AF_INET6; 2731 } 2732 2733 static inline bool sk_is_tcp(const struct sock *sk) 2734 { 2735 return sk_is_inet(sk) && 2736 sk->sk_type == SOCK_STREAM && 2737 sk->sk_protocol == IPPROTO_TCP; 2738 } 2739 2740 static inline bool sk_is_udp(const struct sock *sk) 2741 { 2742 return sk_is_inet(sk) && 2743 sk->sk_type == SOCK_DGRAM && 2744 sk->sk_protocol == IPPROTO_UDP; 2745 } 2746 2747 static inline bool sk_is_stream_unix(const struct sock *sk) 2748 { 2749 return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM; 2750 } 2751 2752 static inline bool sk_is_vsock(const struct sock *sk) 2753 { 2754 return sk->sk_family == AF_VSOCK; 2755 } 2756 2757 /** 2758 * sk_eat_skb - Release a skb if it is no longer needed 2759 * @sk: socket to eat this skb from 2760 * @skb: socket buffer to eat 2761 * 2762 * This routine must be called with interrupts disabled or with the socket 2763 * locked so that the sk_buff queue operation is ok. 2764 */ 2765 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2766 { 2767 __skb_unlink(skb, &sk->sk_receive_queue); 2768 __kfree_skb(skb); 2769 } 2770 2771 static inline bool 2772 skb_sk_is_prefetched(struct sk_buff *skb) 2773 { 2774 #ifdef CONFIG_INET 2775 return skb->destructor == sock_pfree; 2776 #else 2777 return false; 2778 #endif /* CONFIG_INET */ 2779 } 2780 2781 /* This helper checks if a socket is a full socket, 2782 * ie _not_ a timewait or request socket. 2783 */ 2784 static inline bool sk_fullsock(const struct sock *sk) 2785 { 2786 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2787 } 2788 2789 static inline bool 2790 sk_is_refcounted(struct sock *sk) 2791 { 2792 /* Only full sockets have sk->sk_flags. */ 2793 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2794 } 2795 2796 /* Checks if this SKB belongs to an HW offloaded socket 2797 * and whether any SW fallbacks are required based on dev. 2798 * Check decrypted mark in case skb_orphan() cleared socket. 2799 */ 2800 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2801 struct net_device *dev) 2802 { 2803 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2804 struct sock *sk = skb->sk; 2805 2806 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2807 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2808 } else if (unlikely(skb_is_decrypted(skb))) { 2809 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2810 kfree_skb(skb); 2811 skb = NULL; 2812 } 2813 #endif 2814 2815 return skb; 2816 } 2817 2818 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2819 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2820 */ 2821 static inline bool sk_listener(const struct sock *sk) 2822 { 2823 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2824 } 2825 2826 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT 2827 * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE) 2828 * TCP RST and ACK can be attached to TIME_WAIT. 2829 */ 2830 static inline bool sk_listener_or_tw(const struct sock *sk) 2831 { 2832 return (1 << READ_ONCE(sk->sk_state)) & 2833 (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT); 2834 } 2835 2836 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2837 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2838 int type); 2839 2840 bool sk_ns_capable(const struct sock *sk, 2841 struct user_namespace *user_ns, int cap); 2842 bool sk_capable(const struct sock *sk, int cap); 2843 bool sk_net_capable(const struct sock *sk, int cap); 2844 2845 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2846 2847 /* Take into consideration the size of the struct sk_buff overhead in the 2848 * determination of these values, since that is non-constant across 2849 * platforms. This makes socket queueing behavior and performance 2850 * not depend upon such differences. 2851 */ 2852 #define _SK_MEM_PACKETS 256 2853 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2854 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2855 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2856 2857 extern __u32 sysctl_wmem_max; 2858 extern __u32 sysctl_rmem_max; 2859 2860 extern __u32 sysctl_wmem_default; 2861 extern __u32 sysctl_rmem_default; 2862 2863 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2864 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2865 2866 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2867 { 2868 /* Does this proto have per netns sysctl_wmem ? */ 2869 if (proto->sysctl_wmem_offset) 2870 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); 2871 2872 return READ_ONCE(*proto->sysctl_wmem); 2873 } 2874 2875 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2876 { 2877 /* Does this proto have per netns sysctl_rmem ? */ 2878 if (proto->sysctl_rmem_offset) 2879 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); 2880 2881 return READ_ONCE(*proto->sysctl_rmem); 2882 } 2883 2884 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2885 * Some wifi drivers need to tweak it to get more chunks. 2886 * They can use this helper from their ndo_start_xmit() 2887 */ 2888 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2889 { 2890 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2891 return; 2892 WRITE_ONCE(sk->sk_pacing_shift, val); 2893 } 2894 2895 /* if a socket is bound to a device, check that the given device 2896 * index is either the same or that the socket is bound to an L3 2897 * master device and the given device index is also enslaved to 2898 * that L3 master 2899 */ 2900 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2901 { 2902 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 2903 int mdif; 2904 2905 if (!bound_dev_if || bound_dev_if == dif) 2906 return true; 2907 2908 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2909 if (mdif && mdif == bound_dev_if) 2910 return true; 2911 2912 return false; 2913 } 2914 2915 void sock_def_readable(struct sock *sk); 2916 2917 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 2918 void sock_set_timestamp(struct sock *sk, int optname, bool valbool); 2919 int sock_set_timestamping(struct sock *sk, int optname, 2920 struct so_timestamping timestamping); 2921 2922 void sock_enable_timestamps(struct sock *sk); 2923 void sock_no_linger(struct sock *sk); 2924 void sock_set_keepalive(struct sock *sk); 2925 void sock_set_priority(struct sock *sk, u32 priority); 2926 void sock_set_rcvbuf(struct sock *sk, int val); 2927 void sock_set_mark(struct sock *sk, u32 val); 2928 void sock_set_reuseaddr(struct sock *sk); 2929 void sock_set_reuseport(struct sock *sk); 2930 void sock_set_sndtimeo(struct sock *sk, s64 secs); 2931 2932 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 2933 2934 int sock_get_timeout(long timeo, void *optval, bool old_timeval); 2935 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 2936 sockptr_t optval, int optlen, bool old_timeval); 2937 2938 int sock_ioctl_inout(struct sock *sk, unsigned int cmd, 2939 void __user *arg, void *karg, size_t size); 2940 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg); 2941 static inline bool sk_is_readable(struct sock *sk) 2942 { 2943 if (sk->sk_prot->sock_is_readable) 2944 return sk->sk_prot->sock_is_readable(sk); 2945 return false; 2946 } 2947 #endif /* _SOCK_H */ 2948