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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the AF_INET socket handler.
8 *
9 * Version: @(#)sock.h 1.0.4 05/13/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Corey Minyard <wf-rch!minyard@relay.EU.net>
14 * Florian La Roche <flla@stud.uni-sb.de>
15 *
16 * Fixes:
17 * Alan Cox : Volatiles in skbuff pointers. See
18 * skbuff comments. May be overdone,
19 * better to prove they can be removed
20 * than the reverse.
21 * Alan Cox : Added a zapped field for tcp to note
22 * a socket is reset and must stay shut up
23 * Alan Cox : New fields for options
24 * Pauline Middelink : identd support
25 * Alan Cox : Eliminate low level recv/recvfrom
26 * David S. Miller : New socket lookup architecture.
27 * Steve Whitehouse: Default routines for sock_ops
28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
29 * protinfo be just a void pointer, as the
30 * protocol specific parts were moved to
31 * respective headers and ipv4/v6, etc now
32 * use private slabcaches for its socks
33 * Pedro Hortas : New flags field for socket options
34 */
35#ifndef _SOCK_H
36#define _SOCK_H
37
38#include <linux/hardirq.h>
39#include <linux/kernel.h>
40#include <linux/list.h>
41#include <linux/list_nulls.h>
42#include <linux/timer.h>
43#include <linux/cache.h>
44#include <linux/bitops.h>
45#include <linux/lockdep.h>
46#include <linux/netdevice.h>
47#include <linux/skbuff.h> /* struct sk_buff */
48#include <linux/mm.h>
49#include <linux/security.h>
50#include <linux/slab.h>
51#include <linux/uaccess.h>
52#include <linux/page_counter.h>
53#include <linux/memcontrol.h>
54#include <linux/static_key.h>
55#include <linux/sched.h>
56#include <linux/wait.h>
57#include <linux/cgroup-defs.h>
58#include <linux/rbtree.h>
59#include <linux/filter.h>
60#include <linux/rculist_nulls.h>
61#include <linux/poll.h>
62
63#include <linux/atomic.h>
64#include <linux/refcount.h>
65#include <net/dst.h>
66#include <net/checksum.h>
67#include <net/tcp_states.h>
68#include <linux/net_tstamp.h>
69#include <net/smc.h>
70#include <net/l3mdev.h>
71
72/*
73 * This structure really needs to be cleaned up.
74 * Most of it is for TCP, and not used by any of
75 * the other protocols.
76 */
77
78/* Define this to get the SOCK_DBG debugging facility. */
79#define SOCK_DEBUGGING
80#ifdef SOCK_DEBUGGING
81#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
82 printk(KERN_DEBUG msg); } while (0)
83#else
84/* Validate arguments and do nothing */
85static inline __printf(2, 3)
86void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
87{
88}
89#endif
90
91/* This is the per-socket lock. The spinlock provides a synchronization
92 * between user contexts and software interrupt processing, whereas the
93 * mini-semaphore synchronizes multiple users amongst themselves.
94 */
95typedef struct {
96 spinlock_t slock;
97 int owned;
98 wait_queue_head_t wq;
99 /*
100 * We express the mutex-alike socket_lock semantics
101 * to the lock validator by explicitly managing
102 * the slock as a lock variant (in addition to
103 * the slock itself):
104 */
105#ifdef CONFIG_DEBUG_LOCK_ALLOC
106 struct lockdep_map dep_map;
107#endif
108} socket_lock_t;
109
110struct sock;
111struct proto;
112struct net;
113
114typedef __u32 __bitwise __portpair;
115typedef __u64 __bitwise __addrpair;
116
117/**
118 * struct sock_common - minimal network layer representation of sockets
119 * @skc_daddr: Foreign IPv4 addr
120 * @skc_rcv_saddr: Bound local IPv4 addr
121 * @skc_hash: hash value used with various protocol lookup tables
122 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
123 * @skc_dport: placeholder for inet_dport/tw_dport
124 * @skc_num: placeholder for inet_num/tw_num
125 * @skc_family: network address family
126 * @skc_state: Connection state
127 * @skc_reuse: %SO_REUSEADDR setting
128 * @skc_reuseport: %SO_REUSEPORT setting
129 * @skc_bound_dev_if: bound device index if != 0
130 * @skc_bind_node: bind hash linkage for various protocol lookup tables
131 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
132 * @skc_prot: protocol handlers inside a network family
133 * @skc_net: reference to the network namespace of this socket
134 * @skc_node: main hash linkage for various protocol lookup tables
135 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
136 * @skc_tx_queue_mapping: tx queue number for this connection
137 * @skc_rx_queue_mapping: rx queue number for this connection
138 * @skc_flags: place holder for sk_flags
139 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
140 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
141 * @skc_incoming_cpu: record/match cpu processing incoming packets
142 * @skc_refcnt: reference count
143 *
144 * This is the minimal network layer representation of sockets, the header
145 * for struct sock and struct inet_timewait_sock.
146 */
147struct sock_common {
148 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
149 * address on 64bit arches : cf INET_MATCH()
150 */
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_XPS
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
234struct bpf_sk_storage;
235
236/**
237 * struct sock - network layer representation of sockets
238 * @__sk_common: shared layout with inet_timewait_sock
239 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
240 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
241 * @sk_lock: synchronizer
242 * @sk_kern_sock: True if sock is using kernel lock classes
243 * @sk_rcvbuf: size of receive buffer in bytes
244 * @sk_wq: sock wait queue and async head
245 * @sk_rx_dst: receive input route used by early demux
246 * @sk_dst_cache: destination cache
247 * @sk_dst_pending_confirm: need to confirm neighbour
248 * @sk_policy: flow policy
249 * @sk_receive_queue: incoming packets
250 * @sk_wmem_alloc: transmit queue bytes committed
251 * @sk_tsq_flags: TCP Small Queues flags
252 * @sk_write_queue: Packet sending queue
253 * @sk_omem_alloc: "o" is "option" or "other"
254 * @sk_wmem_queued: persistent queue size
255 * @sk_forward_alloc: space allocated forward
256 * @sk_napi_id: id of the last napi context to receive data for sk
257 * @sk_ll_usec: usecs to busypoll when there is no data
258 * @sk_allocation: allocation mode
259 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
260 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
261 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
262 * @sk_sndbuf: size of send buffer in bytes
263 * @__sk_flags_offset: empty field used to determine location of bitfield
264 * @sk_padding: unused element for alignment
265 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
266 * @sk_no_check_rx: allow zero checksum in RX packets
267 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
268 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
269 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
270 * @sk_gso_max_size: Maximum GSO segment size to build
271 * @sk_gso_max_segs: Maximum number of GSO segments
272 * @sk_pacing_shift: scaling factor for TCP Small Queues
273 * @sk_lingertime: %SO_LINGER l_linger setting
274 * @sk_backlog: always used with the per-socket spinlock held
275 * @sk_callback_lock: used with the callbacks in the end of this struct
276 * @sk_error_queue: rarely used
277 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
278 * IPV6_ADDRFORM for instance)
279 * @sk_err: last error
280 * @sk_err_soft: errors that don't cause failure but are the cause of a
281 * persistent failure not just 'timed out'
282 * @sk_drops: raw/udp drops counter
283 * @sk_ack_backlog: current listen backlog
284 * @sk_max_ack_backlog: listen backlog set in listen()
285 * @sk_uid: user id of owner
286 * @sk_priority: %SO_PRIORITY setting
287 * @sk_type: socket type (%SOCK_STREAM, etc)
288 * @sk_protocol: which protocol this socket belongs in this network family
289 * @sk_peer_pid: &struct pid for this socket's peer
290 * @sk_peer_cred: %SO_PEERCRED setting
291 * @sk_rcvlowat: %SO_RCVLOWAT setting
292 * @sk_rcvtimeo: %SO_RCVTIMEO setting
293 * @sk_sndtimeo: %SO_SNDTIMEO setting
294 * @sk_txhash: computed flow hash for use on transmit
295 * @sk_filter: socket filtering instructions
296 * @sk_timer: sock cleanup timer
297 * @sk_stamp: time stamp of last packet received
298 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
299 * @sk_tsflags: SO_TIMESTAMPING socket options
300 * @sk_tskey: counter to disambiguate concurrent tstamp requests
301 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
302 * @sk_socket: Identd and reporting IO signals
303 * @sk_user_data: RPC layer private data
304 * @sk_frag: cached page frag
305 * @sk_peek_off: current peek_offset value
306 * @sk_send_head: front of stuff to transmit
307 * @sk_security: used by security modules
308 * @sk_mark: generic packet mark
309 * @sk_cgrp_data: cgroup data for this cgroup
310 * @sk_memcg: this socket's memory cgroup association
311 * @sk_write_pending: a write to stream socket waits to start
312 * @sk_state_change: callback to indicate change in the state of the sock
313 * @sk_data_ready: callback to indicate there is data to be processed
314 * @sk_write_space: callback to indicate there is bf sending space available
315 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
316 * @sk_backlog_rcv: callback to process the backlog
317 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
318 * @sk_reuseport_cb: reuseport group container
319 * @sk_rcu: used during RCU grace period
320 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
321 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
322 * @sk_txtime_unused: unused txtime flags
323 */
324struct sock {
325 /*
326 * Now struct inet_timewait_sock also uses sock_common, so please just
327 * don't add nothing before this first member (__sk_common) --acme
328 */
329 struct sock_common __sk_common;
330#define sk_node __sk_common.skc_node
331#define sk_nulls_node __sk_common.skc_nulls_node
332#define sk_refcnt __sk_common.skc_refcnt
333#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
334#ifdef CONFIG_XPS
335#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
336#endif
337
338#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
339#define sk_dontcopy_end __sk_common.skc_dontcopy_end
340#define sk_hash __sk_common.skc_hash
341#define sk_portpair __sk_common.skc_portpair
342#define sk_num __sk_common.skc_num
343#define sk_dport __sk_common.skc_dport
344#define sk_addrpair __sk_common.skc_addrpair
345#define sk_daddr __sk_common.skc_daddr
346#define sk_rcv_saddr __sk_common.skc_rcv_saddr
347#define sk_family __sk_common.skc_family
348#define sk_state __sk_common.skc_state
349#define sk_reuse __sk_common.skc_reuse
350#define sk_reuseport __sk_common.skc_reuseport
351#define sk_ipv6only __sk_common.skc_ipv6only
352#define sk_net_refcnt __sk_common.skc_net_refcnt
353#define sk_bound_dev_if __sk_common.skc_bound_dev_if
354#define sk_bind_node __sk_common.skc_bind_node
355#define sk_prot __sk_common.skc_prot
356#define sk_net __sk_common.skc_net
357#define sk_v6_daddr __sk_common.skc_v6_daddr
358#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
359#define sk_cookie __sk_common.skc_cookie
360#define sk_incoming_cpu __sk_common.skc_incoming_cpu
361#define sk_flags __sk_common.skc_flags
362#define sk_rxhash __sk_common.skc_rxhash
363
364 socket_lock_t sk_lock;
365 atomic_t sk_drops;
366 int sk_rcvlowat;
367 struct sk_buff_head sk_error_queue;
368 struct sk_buff *sk_rx_skb_cache;
369 struct sk_buff_head sk_receive_queue;
370 /*
371 * The backlog queue is special, it is always used with
372 * the per-socket spinlock held and requires low latency
373 * access. Therefore we special case it's implementation.
374 * Note : rmem_alloc is in this structure to fill a hole
375 * on 64bit arches, not because its logically part of
376 * backlog.
377 */
378 struct {
379 atomic_t rmem_alloc;
380 int len;
381 struct sk_buff *head;
382 struct sk_buff *tail;
383 } sk_backlog;
384#define sk_rmem_alloc sk_backlog.rmem_alloc
385
386 int sk_forward_alloc;
387#ifdef CONFIG_NET_RX_BUSY_POLL
388 unsigned int sk_ll_usec;
389 /* ===== mostly read cache line ===== */
390 unsigned int sk_napi_id;
391#endif
392 int sk_rcvbuf;
393
394 struct sk_filter __rcu *sk_filter;
395 union {
396 struct socket_wq __rcu *sk_wq;
397 struct socket_wq *sk_wq_raw;
398 };
399#ifdef CONFIG_XFRM
400 struct xfrm_policy __rcu *sk_policy[2];
401#endif
402 struct dst_entry *sk_rx_dst;
403 struct dst_entry __rcu *sk_dst_cache;
404 atomic_t sk_omem_alloc;
405 int sk_sndbuf;
406
407 /* ===== cache line for TX ===== */
408 int sk_wmem_queued;
409 refcount_t sk_wmem_alloc;
410 unsigned long sk_tsq_flags;
411 union {
412 struct sk_buff *sk_send_head;
413 struct rb_root tcp_rtx_queue;
414 };
415 struct sk_buff *sk_tx_skb_cache;
416 struct sk_buff_head sk_write_queue;
417 __s32 sk_peek_off;
418 int sk_write_pending;
419 __u32 sk_dst_pending_confirm;
420 u32 sk_pacing_status; /* see enum sk_pacing */
421 long sk_sndtimeo;
422 struct timer_list sk_timer;
423 __u32 sk_priority;
424 __u32 sk_mark;
425 unsigned long sk_pacing_rate; /* bytes per second */
426 unsigned long sk_max_pacing_rate;
427 struct page_frag sk_frag;
428 netdev_features_t sk_route_caps;
429 netdev_features_t sk_route_nocaps;
430 netdev_features_t sk_route_forced_caps;
431 int sk_gso_type;
432 unsigned int sk_gso_max_size;
433 gfp_t sk_allocation;
434 __u32 sk_txhash;
435
436 /*
437 * Because of non atomicity rules, all
438 * changes are protected by socket lock.
439 */
440 unsigned int __sk_flags_offset[0];
441#ifdef __BIG_ENDIAN_BITFIELD
442#define SK_FL_PROTO_SHIFT 16
443#define SK_FL_PROTO_MASK 0x00ff0000
444
445#define SK_FL_TYPE_SHIFT 0
446#define SK_FL_TYPE_MASK 0x0000ffff
447#else
448#define SK_FL_PROTO_SHIFT 8
449#define SK_FL_PROTO_MASK 0x0000ff00
450
451#define SK_FL_TYPE_SHIFT 16
452#define SK_FL_TYPE_MASK 0xffff0000
453#endif
454
455 unsigned int sk_padding : 1,
456 sk_kern_sock : 1,
457 sk_no_check_tx : 1,
458 sk_no_check_rx : 1,
459 sk_userlocks : 4,
460 sk_protocol : 8,
461 sk_type : 16;
462#define SK_PROTOCOL_MAX U8_MAX
463 u16 sk_gso_max_segs;
464 u8 sk_pacing_shift;
465 unsigned long sk_lingertime;
466 struct proto *sk_prot_creator;
467 rwlock_t sk_callback_lock;
468 int sk_err,
469 sk_err_soft;
470 u32 sk_ack_backlog;
471 u32 sk_max_ack_backlog;
472 kuid_t sk_uid;
473 struct pid *sk_peer_pid;
474 const struct cred *sk_peer_cred;
475 long sk_rcvtimeo;
476 ktime_t sk_stamp;
477#if BITS_PER_LONG==32
478 seqlock_t sk_stamp_seq;
479#endif
480 u16 sk_tsflags;
481 u8 sk_shutdown;
482 u32 sk_tskey;
483 atomic_t sk_zckey;
484
485 u8 sk_clockid;
486 u8 sk_txtime_deadline_mode : 1,
487 sk_txtime_report_errors : 1,
488 sk_txtime_unused : 6;
489
490 struct socket *sk_socket;
491 void *sk_user_data;
492#ifdef CONFIG_SECURITY
493 void *sk_security;
494#endif
495 struct sock_cgroup_data sk_cgrp_data;
496 struct mem_cgroup *sk_memcg;
497 void (*sk_state_change)(struct sock *sk);
498 void (*sk_data_ready)(struct sock *sk);
499 void (*sk_write_space)(struct sock *sk);
500 void (*sk_error_report)(struct sock *sk);
501 int (*sk_backlog_rcv)(struct sock *sk,
502 struct sk_buff *skb);
503#ifdef CONFIG_SOCK_VALIDATE_XMIT
504 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
505 struct net_device *dev,
506 struct sk_buff *skb);
507#endif
508 void (*sk_destruct)(struct sock *sk);
509 struct sock_reuseport __rcu *sk_reuseport_cb;
510#ifdef CONFIG_BPF_SYSCALL
511 struct bpf_sk_storage __rcu *sk_bpf_storage;
512#endif
513 struct rcu_head sk_rcu;
514};
515
516enum sk_pacing {
517 SK_PACING_NONE = 0,
518 SK_PACING_NEEDED = 1,
519 SK_PACING_FQ = 2,
520};
521
522#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
523
524#define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
525#define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
526
527/*
528 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
529 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
530 * on a socket means that the socket will reuse everybody else's port
531 * without looking at the other's sk_reuse value.
532 */
533
534#define SK_NO_REUSE 0
535#define SK_CAN_REUSE 1
536#define SK_FORCE_REUSE 2
537
538int sk_set_peek_off(struct sock *sk, int val);
539
540static inline int sk_peek_offset(struct sock *sk, int flags)
541{
542 if (unlikely(flags & MSG_PEEK)) {
543 return READ_ONCE(sk->sk_peek_off);
544 }
545
546 return 0;
547}
548
549static inline void sk_peek_offset_bwd(struct sock *sk, int val)
550{
551 s32 off = READ_ONCE(sk->sk_peek_off);
552
553 if (unlikely(off >= 0)) {
554 off = max_t(s32, off - val, 0);
555 WRITE_ONCE(sk->sk_peek_off, off);
556 }
557}
558
559static inline void sk_peek_offset_fwd(struct sock *sk, int val)
560{
561 sk_peek_offset_bwd(sk, -val);
562}
563
564/*
565 * Hashed lists helper routines
566 */
567static inline struct sock *sk_entry(const struct hlist_node *node)
568{
569 return hlist_entry(node, struct sock, sk_node);
570}
571
572static inline struct sock *__sk_head(const struct hlist_head *head)
573{
574 return hlist_entry(head->first, struct sock, sk_node);
575}
576
577static inline struct sock *sk_head(const struct hlist_head *head)
578{
579 return hlist_empty(head) ? NULL : __sk_head(head);
580}
581
582static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
583{
584 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
585}
586
587static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
588{
589 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
590}
591
592static inline struct sock *sk_next(const struct sock *sk)
593{
594 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
595}
596
597static inline struct sock *sk_nulls_next(const struct sock *sk)
598{
599 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
600 hlist_nulls_entry(sk->sk_nulls_node.next,
601 struct sock, sk_nulls_node) :
602 NULL;
603}
604
605static inline bool sk_unhashed(const struct sock *sk)
606{
607 return hlist_unhashed(&sk->sk_node);
608}
609
610static inline bool sk_hashed(const struct sock *sk)
611{
612 return !sk_unhashed(sk);
613}
614
615static inline void sk_node_init(struct hlist_node *node)
616{
617 node->pprev = NULL;
618}
619
620static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
621{
622 node->pprev = NULL;
623}
624
625static inline void __sk_del_node(struct sock *sk)
626{
627 __hlist_del(&sk->sk_node);
628}
629
630/* NB: equivalent to hlist_del_init_rcu */
631static inline bool __sk_del_node_init(struct sock *sk)
632{
633 if (sk_hashed(sk)) {
634 __sk_del_node(sk);
635 sk_node_init(&sk->sk_node);
636 return true;
637 }
638 return false;
639}
640
641/* Grab socket reference count. This operation is valid only
642 when sk is ALREADY grabbed f.e. it is found in hash table
643 or a list and the lookup is made under lock preventing hash table
644 modifications.
645 */
646
647static __always_inline void sock_hold(struct sock *sk)
648{
649 refcount_inc(&sk->sk_refcnt);
650}
651
652/* Ungrab socket in the context, which assumes that socket refcnt
653 cannot hit zero, f.e. it is true in context of any socketcall.
654 */
655static __always_inline void __sock_put(struct sock *sk)
656{
657 refcount_dec(&sk->sk_refcnt);
658}
659
660static inline bool sk_del_node_init(struct sock *sk)
661{
662 bool rc = __sk_del_node_init(sk);
663
664 if (rc) {
665 /* paranoid for a while -acme */
666 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
667 __sock_put(sk);
668 }
669 return rc;
670}
671#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
672
673static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
674{
675 if (sk_hashed(sk)) {
676 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
677 return true;
678 }
679 return false;
680}
681
682static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
683{
684 bool rc = __sk_nulls_del_node_init_rcu(sk);
685
686 if (rc) {
687 /* paranoid for a while -acme */
688 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
689 __sock_put(sk);
690 }
691 return rc;
692}
693
694static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
695{
696 hlist_add_head(&sk->sk_node, list);
697}
698
699static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
700{
701 sock_hold(sk);
702 __sk_add_node(sk, list);
703}
704
705static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
706{
707 sock_hold(sk);
708 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
709 sk->sk_family == AF_INET6)
710 hlist_add_tail_rcu(&sk->sk_node, list);
711 else
712 hlist_add_head_rcu(&sk->sk_node, list);
713}
714
715static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
716{
717 sock_hold(sk);
718 hlist_add_tail_rcu(&sk->sk_node, list);
719}
720
721static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
722{
723 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
724}
725
726static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
727{
728 sock_hold(sk);
729 __sk_nulls_add_node_rcu(sk, list);
730}
731
732static inline void __sk_del_bind_node(struct sock *sk)
733{
734 __hlist_del(&sk->sk_bind_node);
735}
736
737static inline void sk_add_bind_node(struct sock *sk,
738 struct hlist_head *list)
739{
740 hlist_add_head(&sk->sk_bind_node, list);
741}
742
743#define sk_for_each(__sk, list) \
744 hlist_for_each_entry(__sk, list, sk_node)
745#define sk_for_each_rcu(__sk, list) \
746 hlist_for_each_entry_rcu(__sk, list, sk_node)
747#define sk_nulls_for_each(__sk, node, list) \
748 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
749#define sk_nulls_for_each_rcu(__sk, node, list) \
750 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
751#define sk_for_each_from(__sk) \
752 hlist_for_each_entry_from(__sk, sk_node)
753#define sk_nulls_for_each_from(__sk, node) \
754 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
755 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
756#define sk_for_each_safe(__sk, tmp, list) \
757 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
758#define sk_for_each_bound(__sk, list) \
759 hlist_for_each_entry(__sk, list, sk_bind_node)
760
761/**
762 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
763 * @tpos: the type * to use as a loop cursor.
764 * @pos: the &struct hlist_node to use as a loop cursor.
765 * @head: the head for your list.
766 * @offset: offset of hlist_node within the struct.
767 *
768 */
769#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
770 for (pos = rcu_dereference(hlist_first_rcu(head)); \
771 pos != NULL && \
772 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
773 pos = rcu_dereference(hlist_next_rcu(pos)))
774
775static inline struct user_namespace *sk_user_ns(struct sock *sk)
776{
777 /* Careful only use this in a context where these parameters
778 * can not change and must all be valid, such as recvmsg from
779 * userspace.
780 */
781 return sk->sk_socket->file->f_cred->user_ns;
782}
783
784/* Sock flags */
785enum sock_flags {
786 SOCK_DEAD,
787 SOCK_DONE,
788 SOCK_URGINLINE,
789 SOCK_KEEPOPEN,
790 SOCK_LINGER,
791 SOCK_DESTROY,
792 SOCK_BROADCAST,
793 SOCK_TIMESTAMP,
794 SOCK_ZAPPED,
795 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
796 SOCK_DBG, /* %SO_DEBUG setting */
797 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
798 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
799 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
800 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
801 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
802 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
803 SOCK_FASYNC, /* fasync() active */
804 SOCK_RXQ_OVFL,
805 SOCK_ZEROCOPY, /* buffers from userspace */
806 SOCK_WIFI_STATUS, /* push wifi status to userspace */
807 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
808 * Will use last 4 bytes of packet sent from
809 * user-space instead.
810 */
811 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
812 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
813 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
814 SOCK_TXTIME,
815 SOCK_XDP, /* XDP is attached */
816 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
817};
818
819#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
820
821static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
822{
823 nsk->sk_flags = osk->sk_flags;
824}
825
826static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
827{
828 __set_bit(flag, &sk->sk_flags);
829}
830
831static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
832{
833 __clear_bit(flag, &sk->sk_flags);
834}
835
836static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
837{
838 return test_bit(flag, &sk->sk_flags);
839}
840
841#ifdef CONFIG_NET
842DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
843static inline int sk_memalloc_socks(void)
844{
845 return static_branch_unlikely(&memalloc_socks_key);
846}
847#else
848
849static inline int sk_memalloc_socks(void)
850{
851 return 0;
852}
853
854#endif
855
856static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
857{
858 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
859}
860
861static inline void sk_acceptq_removed(struct sock *sk)
862{
863 sk->sk_ack_backlog--;
864}
865
866static inline void sk_acceptq_added(struct sock *sk)
867{
868 sk->sk_ack_backlog++;
869}
870
871static inline bool sk_acceptq_is_full(const struct sock *sk)
872{
873 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
874}
875
876/*
877 * Compute minimal free write space needed to queue new packets.
878 */
879static inline int sk_stream_min_wspace(const struct sock *sk)
880{
881 return READ_ONCE(sk->sk_wmem_queued) >> 1;
882}
883
884static inline int sk_stream_wspace(const struct sock *sk)
885{
886 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
887}
888
889static inline void sk_wmem_queued_add(struct sock *sk, int val)
890{
891 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
892}
893
894void sk_stream_write_space(struct sock *sk);
895
896/* OOB backlog add */
897static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
898{
899 /* dont let skb dst not refcounted, we are going to leave rcu lock */
900 skb_dst_force(skb);
901
902 if (!sk->sk_backlog.tail)
903 sk->sk_backlog.head = skb;
904 else
905 sk->sk_backlog.tail->next = skb;
906
907 sk->sk_backlog.tail = skb;
908 skb->next = NULL;
909}
910
911/*
912 * Take into account size of receive queue and backlog queue
913 * Do not take into account this skb truesize,
914 * to allow even a single big packet to come.
915 */
916static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
917{
918 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
919
920 return qsize > limit;
921}
922
923/* The per-socket spinlock must be held here. */
924static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
925 unsigned int limit)
926{
927 if (sk_rcvqueues_full(sk, limit))
928 return -ENOBUFS;
929
930 /*
931 * If the skb was allocated from pfmemalloc reserves, only
932 * allow SOCK_MEMALLOC sockets to use it as this socket is
933 * helping free memory
934 */
935 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
936 return -ENOMEM;
937
938 __sk_add_backlog(sk, skb);
939 sk->sk_backlog.len += skb->truesize;
940 return 0;
941}
942
943int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
944
945static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
946{
947 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
948 return __sk_backlog_rcv(sk, skb);
949
950 return sk->sk_backlog_rcv(sk, skb);
951}
952
953static inline void sk_incoming_cpu_update(struct sock *sk)
954{
955 int cpu = raw_smp_processor_id();
956
957 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
958 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
959}
960
961static inline void sock_rps_record_flow_hash(__u32 hash)
962{
963#ifdef CONFIG_RPS
964 struct rps_sock_flow_table *sock_flow_table;
965
966 rcu_read_lock();
967 sock_flow_table = rcu_dereference(rps_sock_flow_table);
968 rps_record_sock_flow(sock_flow_table, hash);
969 rcu_read_unlock();
970#endif
971}
972
973static inline void sock_rps_record_flow(const struct sock *sk)
974{
975#ifdef CONFIG_RPS
976 if (static_branch_unlikely(&rfs_needed)) {
977 /* Reading sk->sk_rxhash might incur an expensive cache line
978 * miss.
979 *
980 * TCP_ESTABLISHED does cover almost all states where RFS
981 * might be useful, and is cheaper [1] than testing :
982 * IPv4: inet_sk(sk)->inet_daddr
983 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
984 * OR an additional socket flag
985 * [1] : sk_state and sk_prot are in the same cache line.
986 */
987 if (sk->sk_state == TCP_ESTABLISHED)
988 sock_rps_record_flow_hash(sk->sk_rxhash);
989 }
990#endif
991}
992
993static inline void sock_rps_save_rxhash(struct sock *sk,
994 const struct sk_buff *skb)
995{
996#ifdef CONFIG_RPS
997 if (unlikely(sk->sk_rxhash != skb->hash))
998 sk->sk_rxhash = skb->hash;
999#endif
1000}
1001
1002static inline void sock_rps_reset_rxhash(struct sock *sk)
1003{
1004#ifdef CONFIG_RPS
1005 sk->sk_rxhash = 0;
1006#endif
1007}
1008
1009#define sk_wait_event(__sk, __timeo, __condition, __wait) \
1010 ({ int __rc; \
1011 release_sock(__sk); \
1012 __rc = __condition; \
1013 if (!__rc) { \
1014 *(__timeo) = wait_woken(__wait, \
1015 TASK_INTERRUPTIBLE, \
1016 *(__timeo)); \
1017 } \
1018 sched_annotate_sleep(); \
1019 lock_sock(__sk); \
1020 __rc = __condition; \
1021 __rc; \
1022 })
1023
1024int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1025int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1026void sk_stream_wait_close(struct sock *sk, long timeo_p);
1027int sk_stream_error(struct sock *sk, int flags, int err);
1028void sk_stream_kill_queues(struct sock *sk);
1029void sk_set_memalloc(struct sock *sk);
1030void sk_clear_memalloc(struct sock *sk);
1031
1032void __sk_flush_backlog(struct sock *sk);
1033
1034static inline bool sk_flush_backlog(struct sock *sk)
1035{
1036 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1037 __sk_flush_backlog(sk);
1038 return true;
1039 }
1040 return false;
1041}
1042
1043int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1044
1045struct request_sock_ops;
1046struct timewait_sock_ops;
1047struct inet_hashinfo;
1048struct raw_hashinfo;
1049struct smc_hashinfo;
1050struct module;
1051
1052/*
1053 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1054 * un-modified. Special care is taken when initializing object to zero.
1055 */
1056static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1057{
1058 if (offsetof(struct sock, sk_node.next) != 0)
1059 memset(sk, 0, offsetof(struct sock, sk_node.next));
1060 memset(&sk->sk_node.pprev, 0,
1061 size - offsetof(struct sock, sk_node.pprev));
1062}
1063
1064/* Networking protocol blocks we attach to sockets.
1065 * socket layer -> transport layer interface
1066 */
1067struct proto {
1068 void (*close)(struct sock *sk,
1069 long timeout);
1070 int (*pre_connect)(struct sock *sk,
1071 struct sockaddr *uaddr,
1072 int addr_len);
1073 int (*connect)(struct sock *sk,
1074 struct sockaddr *uaddr,
1075 int addr_len);
1076 int (*disconnect)(struct sock *sk, int flags);
1077
1078 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1079 bool kern);
1080
1081 int (*ioctl)(struct sock *sk, int cmd,
1082 unsigned long arg);
1083 int (*init)(struct sock *sk);
1084 void (*destroy)(struct sock *sk);
1085 void (*shutdown)(struct sock *sk, int how);
1086 int (*setsockopt)(struct sock *sk, int level,
1087 int optname, char __user *optval,
1088 unsigned int optlen);
1089 int (*getsockopt)(struct sock *sk, int level,
1090 int optname, char __user *optval,
1091 int __user *option);
1092 void (*keepalive)(struct sock *sk, int valbool);
1093#ifdef CONFIG_COMPAT
1094 int (*compat_setsockopt)(struct sock *sk,
1095 int level,
1096 int optname, char __user *optval,
1097 unsigned int optlen);
1098 int (*compat_getsockopt)(struct sock *sk,
1099 int level,
1100 int optname, char __user *optval,
1101 int __user *option);
1102 int (*compat_ioctl)(struct sock *sk,
1103 unsigned int cmd, unsigned long arg);
1104#endif
1105 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1106 size_t len);
1107 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1108 size_t len, int noblock, int flags,
1109 int *addr_len);
1110 int (*sendpage)(struct sock *sk, struct page *page,
1111 int offset, size_t size, int flags);
1112 int (*bind)(struct sock *sk,
1113 struct sockaddr *uaddr, int addr_len);
1114
1115 int (*backlog_rcv) (struct sock *sk,
1116 struct sk_buff *skb);
1117
1118 void (*release_cb)(struct sock *sk);
1119
1120 /* Keeping track of sk's, looking them up, and port selection methods. */
1121 int (*hash)(struct sock *sk);
1122 void (*unhash)(struct sock *sk);
1123 void (*rehash)(struct sock *sk);
1124 int (*get_port)(struct sock *sk, unsigned short snum);
1125
1126 /* Keeping track of sockets in use */
1127#ifdef CONFIG_PROC_FS
1128 unsigned int inuse_idx;
1129#endif
1130
1131 bool (*stream_memory_free)(const struct sock *sk, int wake);
1132 bool (*stream_memory_read)(const struct sock *sk);
1133 /* Memory pressure */
1134 void (*enter_memory_pressure)(struct sock *sk);
1135 void (*leave_memory_pressure)(struct sock *sk);
1136 atomic_long_t *memory_allocated; /* Current allocated memory. */
1137 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1138 /*
1139 * Pressure flag: try to collapse.
1140 * Technical note: it is used by multiple contexts non atomically.
1141 * All the __sk_mem_schedule() is of this nature: accounting
1142 * is strict, actions are advisory and have some latency.
1143 */
1144 unsigned long *memory_pressure;
1145 long *sysctl_mem;
1146
1147 int *sysctl_wmem;
1148 int *sysctl_rmem;
1149 u32 sysctl_wmem_offset;
1150 u32 sysctl_rmem_offset;
1151
1152 int max_header;
1153 bool no_autobind;
1154
1155 struct kmem_cache *slab;
1156 unsigned int obj_size;
1157 slab_flags_t slab_flags;
1158 unsigned int useroffset; /* Usercopy region offset */
1159 unsigned int usersize; /* Usercopy region size */
1160
1161 struct percpu_counter *orphan_count;
1162
1163 struct request_sock_ops *rsk_prot;
1164 struct timewait_sock_ops *twsk_prot;
1165
1166 union {
1167 struct inet_hashinfo *hashinfo;
1168 struct udp_table *udp_table;
1169 struct raw_hashinfo *raw_hash;
1170 struct smc_hashinfo *smc_hash;
1171 } h;
1172
1173 struct module *owner;
1174
1175 char name[32];
1176
1177 struct list_head node;
1178#ifdef SOCK_REFCNT_DEBUG
1179 atomic_t socks;
1180#endif
1181 int (*diag_destroy)(struct sock *sk, int err);
1182} __randomize_layout;
1183
1184int proto_register(struct proto *prot, int alloc_slab);
1185void proto_unregister(struct proto *prot);
1186int sock_load_diag_module(int family, int protocol);
1187
1188#ifdef SOCK_REFCNT_DEBUG
1189static inline void sk_refcnt_debug_inc(struct sock *sk)
1190{
1191 atomic_inc(&sk->sk_prot->socks);
1192}
1193
1194static inline void sk_refcnt_debug_dec(struct sock *sk)
1195{
1196 atomic_dec(&sk->sk_prot->socks);
1197 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1198 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1199}
1200
1201static inline void sk_refcnt_debug_release(const struct sock *sk)
1202{
1203 if (refcount_read(&sk->sk_refcnt) != 1)
1204 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1205 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1206}
1207#else /* SOCK_REFCNT_DEBUG */
1208#define sk_refcnt_debug_inc(sk) do { } while (0)
1209#define sk_refcnt_debug_dec(sk) do { } while (0)
1210#define sk_refcnt_debug_release(sk) do { } while (0)
1211#endif /* SOCK_REFCNT_DEBUG */
1212
1213static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1214{
1215 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1216 return false;
1217
1218 return sk->sk_prot->stream_memory_free ?
1219 sk->sk_prot->stream_memory_free(sk, wake) : true;
1220}
1221
1222static inline bool sk_stream_memory_free(const struct sock *sk)
1223{
1224 return __sk_stream_memory_free(sk, 0);
1225}
1226
1227static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1228{
1229 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1230 __sk_stream_memory_free(sk, wake);
1231}
1232
1233static inline bool sk_stream_is_writeable(const struct sock *sk)
1234{
1235 return __sk_stream_is_writeable(sk, 0);
1236}
1237
1238static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1239 struct cgroup *ancestor)
1240{
1241#ifdef CONFIG_SOCK_CGROUP_DATA
1242 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1243 ancestor);
1244#else
1245 return -ENOTSUPP;
1246#endif
1247}
1248
1249static inline bool sk_has_memory_pressure(const struct sock *sk)
1250{
1251 return sk->sk_prot->memory_pressure != NULL;
1252}
1253
1254static inline bool sk_under_memory_pressure(const struct sock *sk)
1255{
1256 if (!sk->sk_prot->memory_pressure)
1257 return false;
1258
1259 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1260 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1261 return true;
1262
1263 return !!*sk->sk_prot->memory_pressure;
1264}
1265
1266static inline long
1267sk_memory_allocated(const struct sock *sk)
1268{
1269 return atomic_long_read(sk->sk_prot->memory_allocated);
1270}
1271
1272static inline long
1273sk_memory_allocated_add(struct sock *sk, int amt)
1274{
1275 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1276}
1277
1278static inline void
1279sk_memory_allocated_sub(struct sock *sk, int amt)
1280{
1281 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1282}
1283
1284static inline void sk_sockets_allocated_dec(struct sock *sk)
1285{
1286 percpu_counter_dec(sk->sk_prot->sockets_allocated);
1287}
1288
1289static inline void sk_sockets_allocated_inc(struct sock *sk)
1290{
1291 percpu_counter_inc(sk->sk_prot->sockets_allocated);
1292}
1293
1294static inline u64
1295sk_sockets_allocated_read_positive(struct sock *sk)
1296{
1297 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1298}
1299
1300static inline int
1301proto_sockets_allocated_sum_positive(struct proto *prot)
1302{
1303 return percpu_counter_sum_positive(prot->sockets_allocated);
1304}
1305
1306static inline long
1307proto_memory_allocated(struct proto *prot)
1308{
1309 return atomic_long_read(prot->memory_allocated);
1310}
1311
1312static inline bool
1313proto_memory_pressure(struct proto *prot)
1314{
1315 if (!prot->memory_pressure)
1316 return false;
1317 return !!*prot->memory_pressure;
1318}
1319
1320
1321#ifdef CONFIG_PROC_FS
1322/* Called with local bh disabled */
1323void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1324int sock_prot_inuse_get(struct net *net, struct proto *proto);
1325int sock_inuse_get(struct net *net);
1326#else
1327static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1328 int inc)
1329{
1330}
1331#endif
1332
1333
1334/* With per-bucket locks this operation is not-atomic, so that
1335 * this version is not worse.
1336 */
1337static inline int __sk_prot_rehash(struct sock *sk)
1338{
1339 sk->sk_prot->unhash(sk);
1340 return sk->sk_prot->hash(sk);
1341}
1342
1343/* About 10 seconds */
1344#define SOCK_DESTROY_TIME (10*HZ)
1345
1346/* Sockets 0-1023 can't be bound to unless you are superuser */
1347#define PROT_SOCK 1024
1348
1349#define SHUTDOWN_MASK 3
1350#define RCV_SHUTDOWN 1
1351#define SEND_SHUTDOWN 2
1352
1353#define SOCK_SNDBUF_LOCK 1
1354#define SOCK_RCVBUF_LOCK 2
1355#define SOCK_BINDADDR_LOCK 4
1356#define SOCK_BINDPORT_LOCK 8
1357
1358struct socket_alloc {
1359 struct socket socket;
1360 struct inode vfs_inode;
1361};
1362
1363static inline struct socket *SOCKET_I(struct inode *inode)
1364{
1365 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1366}
1367
1368static inline struct inode *SOCK_INODE(struct socket *socket)
1369{
1370 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1371}
1372
1373/*
1374 * Functions for memory accounting
1375 */
1376int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1377int __sk_mem_schedule(struct sock *sk, int size, int kind);
1378void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1379void __sk_mem_reclaim(struct sock *sk, int amount);
1380
1381/* We used to have PAGE_SIZE here, but systems with 64KB pages
1382 * do not necessarily have 16x time more memory than 4KB ones.
1383 */
1384#define SK_MEM_QUANTUM 4096
1385#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1386#define SK_MEM_SEND 0
1387#define SK_MEM_RECV 1
1388
1389/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1390static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1391{
1392 long val = sk->sk_prot->sysctl_mem[index];
1393
1394#if PAGE_SIZE > SK_MEM_QUANTUM
1395 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1396#elif PAGE_SIZE < SK_MEM_QUANTUM
1397 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1398#endif
1399 return val;
1400}
1401
1402static inline int sk_mem_pages(int amt)
1403{
1404 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1405}
1406
1407static inline bool sk_has_account(struct sock *sk)
1408{
1409 /* return true if protocol supports memory accounting */
1410 return !!sk->sk_prot->memory_allocated;
1411}
1412
1413static inline bool sk_wmem_schedule(struct sock *sk, int size)
1414{
1415 if (!sk_has_account(sk))
1416 return true;
1417 return size <= sk->sk_forward_alloc ||
1418 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1419}
1420
1421static inline bool
1422sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1423{
1424 if (!sk_has_account(sk))
1425 return true;
1426 return size<= sk->sk_forward_alloc ||
1427 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1428 skb_pfmemalloc(skb);
1429}
1430
1431static inline void sk_mem_reclaim(struct sock *sk)
1432{
1433 if (!sk_has_account(sk))
1434 return;
1435 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1436 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1437}
1438
1439static inline void sk_mem_reclaim_partial(struct sock *sk)
1440{
1441 if (!sk_has_account(sk))
1442 return;
1443 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1444 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1445}
1446
1447static inline void sk_mem_charge(struct sock *sk, int size)
1448{
1449 if (!sk_has_account(sk))
1450 return;
1451 sk->sk_forward_alloc -= size;
1452}
1453
1454static inline void sk_mem_uncharge(struct sock *sk, int size)
1455{
1456 if (!sk_has_account(sk))
1457 return;
1458 sk->sk_forward_alloc += size;
1459
1460 /* Avoid a possible overflow.
1461 * TCP send queues can make this happen, if sk_mem_reclaim()
1462 * is not called and more than 2 GBytes are released at once.
1463 *
1464 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1465 * no need to hold that much forward allocation anyway.
1466 */
1467 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1468 __sk_mem_reclaim(sk, 1 << 20);
1469}
1470
1471DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
1472static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1473{
1474 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1475 sk_wmem_queued_add(sk, -skb->truesize);
1476 sk_mem_uncharge(sk, skb->truesize);
1477 if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1478 !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1479 skb_zcopy_clear(skb, true);
1480 sk->sk_tx_skb_cache = skb;
1481 return;
1482 }
1483 __kfree_skb(skb);
1484}
1485
1486static inline void sock_release_ownership(struct sock *sk)
1487{
1488 if (sk->sk_lock.owned) {
1489 sk->sk_lock.owned = 0;
1490
1491 /* The sk_lock has mutex_unlock() semantics: */
1492 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1493 }
1494}
1495
1496/*
1497 * Macro so as to not evaluate some arguments when
1498 * lockdep is not enabled.
1499 *
1500 * Mark both the sk_lock and the sk_lock.slock as a
1501 * per-address-family lock class.
1502 */
1503#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1504do { \
1505 sk->sk_lock.owned = 0; \
1506 init_waitqueue_head(&sk->sk_lock.wq); \
1507 spin_lock_init(&(sk)->sk_lock.slock); \
1508 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1509 sizeof((sk)->sk_lock)); \
1510 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1511 (skey), (sname)); \
1512 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1513} while (0)
1514
1515#ifdef CONFIG_LOCKDEP
1516static inline bool lockdep_sock_is_held(const struct sock *sk)
1517{
1518 return lockdep_is_held(&sk->sk_lock) ||
1519 lockdep_is_held(&sk->sk_lock.slock);
1520}
1521#endif
1522
1523void lock_sock_nested(struct sock *sk, int subclass);
1524
1525static inline void lock_sock(struct sock *sk)
1526{
1527 lock_sock_nested(sk, 0);
1528}
1529
1530void __release_sock(struct sock *sk);
1531void release_sock(struct sock *sk);
1532
1533/* BH context may only use the following locking interface. */
1534#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1535#define bh_lock_sock_nested(__sk) \
1536 spin_lock_nested(&((__sk)->sk_lock.slock), \
1537 SINGLE_DEPTH_NESTING)
1538#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1539
1540bool lock_sock_fast(struct sock *sk);
1541/**
1542 * unlock_sock_fast - complement of lock_sock_fast
1543 * @sk: socket
1544 * @slow: slow mode
1545 *
1546 * fast unlock socket for user context.
1547 * If slow mode is on, we call regular release_sock()
1548 */
1549static inline void unlock_sock_fast(struct sock *sk, bool slow)
1550{
1551 if (slow)
1552 release_sock(sk);
1553 else
1554 spin_unlock_bh(&sk->sk_lock.slock);
1555}
1556
1557/* Used by processes to "lock" a socket state, so that
1558 * interrupts and bottom half handlers won't change it
1559 * from under us. It essentially blocks any incoming
1560 * packets, so that we won't get any new data or any
1561 * packets that change the state of the socket.
1562 *
1563 * While locked, BH processing will add new packets to
1564 * the backlog queue. This queue is processed by the
1565 * owner of the socket lock right before it is released.
1566 *
1567 * Since ~2.3.5 it is also exclusive sleep lock serializing
1568 * accesses from user process context.
1569 */
1570
1571static inline void sock_owned_by_me(const struct sock *sk)
1572{
1573#ifdef CONFIG_LOCKDEP
1574 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1575#endif
1576}
1577
1578static inline bool sock_owned_by_user(const struct sock *sk)
1579{
1580 sock_owned_by_me(sk);
1581 return sk->sk_lock.owned;
1582}
1583
1584static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1585{
1586 return sk->sk_lock.owned;
1587}
1588
1589/* no reclassification while locks are held */
1590static inline bool sock_allow_reclassification(const struct sock *csk)
1591{
1592 struct sock *sk = (struct sock *)csk;
1593
1594 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1595}
1596
1597struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1598 struct proto *prot, int kern);
1599void sk_free(struct sock *sk);
1600void sk_destruct(struct sock *sk);
1601struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1602void sk_free_unlock_clone(struct sock *sk);
1603
1604struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1605 gfp_t priority);
1606void __sock_wfree(struct sk_buff *skb);
1607void sock_wfree(struct sk_buff *skb);
1608struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1609 gfp_t priority);
1610void skb_orphan_partial(struct sk_buff *skb);
1611void sock_rfree(struct sk_buff *skb);
1612void sock_efree(struct sk_buff *skb);
1613#ifdef CONFIG_INET
1614void sock_edemux(struct sk_buff *skb);
1615#else
1616#define sock_edemux sock_efree
1617#endif
1618
1619int sock_setsockopt(struct socket *sock, int level, int op,
1620 char __user *optval, unsigned int optlen);
1621
1622int sock_getsockopt(struct socket *sock, int level, int op,
1623 char __user *optval, int __user *optlen);
1624int sock_gettstamp(struct socket *sock, void __user *userstamp,
1625 bool timeval, bool time32);
1626struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1627 int noblock, int *errcode);
1628struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1629 unsigned long data_len, int noblock,
1630 int *errcode, int max_page_order);
1631void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1632void sock_kfree_s(struct sock *sk, void *mem, int size);
1633void sock_kzfree_s(struct sock *sk, void *mem, int size);
1634void sk_send_sigurg(struct sock *sk);
1635
1636struct sockcm_cookie {
1637 u64 transmit_time;
1638 u32 mark;
1639 u16 tsflags;
1640};
1641
1642static inline void sockcm_init(struct sockcm_cookie *sockc,
1643 const struct sock *sk)
1644{
1645 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1646}
1647
1648int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1649 struct sockcm_cookie *sockc);
1650int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1651 struct sockcm_cookie *sockc);
1652
1653/*
1654 * Functions to fill in entries in struct proto_ops when a protocol
1655 * does not implement a particular function.
1656 */
1657int sock_no_bind(struct socket *, struct sockaddr *, int);
1658int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1659int sock_no_socketpair(struct socket *, struct socket *);
1660int sock_no_accept(struct socket *, struct socket *, int, bool);
1661int sock_no_getname(struct socket *, struct sockaddr *, int);
1662int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1663int sock_no_listen(struct socket *, int);
1664int sock_no_shutdown(struct socket *, int);
1665int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1666int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1667int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1668int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1669int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1670int sock_no_mmap(struct file *file, struct socket *sock,
1671 struct vm_area_struct *vma);
1672ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1673 size_t size, int flags);
1674ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1675 int offset, size_t size, int flags);
1676
1677/*
1678 * Functions to fill in entries in struct proto_ops when a protocol
1679 * uses the inet style.
1680 */
1681int sock_common_getsockopt(struct socket *sock, int level, int optname,
1682 char __user *optval, int __user *optlen);
1683int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1684 int flags);
1685int sock_common_setsockopt(struct socket *sock, int level, int optname,
1686 char __user *optval, unsigned int optlen);
1687int compat_sock_common_getsockopt(struct socket *sock, int level,
1688 int optname, char __user *optval, int __user *optlen);
1689int compat_sock_common_setsockopt(struct socket *sock, int level,
1690 int optname, char __user *optval, unsigned int optlen);
1691
1692void sk_common_release(struct sock *sk);
1693
1694/*
1695 * Default socket callbacks and setup code
1696 */
1697
1698/* Initialise core socket variables */
1699void sock_init_data(struct socket *sock, struct sock *sk);
1700
1701/*
1702 * Socket reference counting postulates.
1703 *
1704 * * Each user of socket SHOULD hold a reference count.
1705 * * Each access point to socket (an hash table bucket, reference from a list,
1706 * running timer, skb in flight MUST hold a reference count.
1707 * * When reference count hits 0, it means it will never increase back.
1708 * * When reference count hits 0, it means that no references from
1709 * outside exist to this socket and current process on current CPU
1710 * is last user and may/should destroy this socket.
1711 * * sk_free is called from any context: process, BH, IRQ. When
1712 * it is called, socket has no references from outside -> sk_free
1713 * may release descendant resources allocated by the socket, but
1714 * to the time when it is called, socket is NOT referenced by any
1715 * hash tables, lists etc.
1716 * * Packets, delivered from outside (from network or from another process)
1717 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1718 * when they sit in queue. Otherwise, packets will leak to hole, when
1719 * socket is looked up by one cpu and unhasing is made by another CPU.
1720 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1721 * (leak to backlog). Packet socket does all the processing inside
1722 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1723 * use separate SMP lock, so that they are prone too.
1724 */
1725
1726/* Ungrab socket and destroy it, if it was the last reference. */
1727static inline void sock_put(struct sock *sk)
1728{
1729 if (refcount_dec_and_test(&sk->sk_refcnt))
1730 sk_free(sk);
1731}
1732/* Generic version of sock_put(), dealing with all sockets
1733 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1734 */
1735void sock_gen_put(struct sock *sk);
1736
1737int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1738 unsigned int trim_cap, bool refcounted);
1739static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1740 const int nested)
1741{
1742 return __sk_receive_skb(sk, skb, nested, 1, true);
1743}
1744
1745static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1746{
1747 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1748 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1749 return;
1750 sk->sk_tx_queue_mapping = tx_queue;
1751}
1752
1753#define NO_QUEUE_MAPPING USHRT_MAX
1754
1755static inline void sk_tx_queue_clear(struct sock *sk)
1756{
1757 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1758}
1759
1760static inline int sk_tx_queue_get(const struct sock *sk)
1761{
1762 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1763 return sk->sk_tx_queue_mapping;
1764
1765 return -1;
1766}
1767
1768static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1769{
1770#ifdef CONFIG_XPS
1771 if (skb_rx_queue_recorded(skb)) {
1772 u16 rx_queue = skb_get_rx_queue(skb);
1773
1774 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1775 return;
1776
1777 sk->sk_rx_queue_mapping = rx_queue;
1778 }
1779#endif
1780}
1781
1782static inline void sk_rx_queue_clear(struct sock *sk)
1783{
1784#ifdef CONFIG_XPS
1785 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1786#endif
1787}
1788
1789#ifdef CONFIG_XPS
1790static inline int sk_rx_queue_get(const struct sock *sk)
1791{
1792 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1793 return sk->sk_rx_queue_mapping;
1794
1795 return -1;
1796}
1797#endif
1798
1799static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1800{
1801 sk_tx_queue_clear(sk);
1802 sk->sk_socket = sock;
1803}
1804
1805static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1806{
1807 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1808 return &rcu_dereference_raw(sk->sk_wq)->wait;
1809}
1810/* Detach socket from process context.
1811 * Announce socket dead, detach it from wait queue and inode.
1812 * Note that parent inode held reference count on this struct sock,
1813 * we do not release it in this function, because protocol
1814 * probably wants some additional cleanups or even continuing
1815 * to work with this socket (TCP).
1816 */
1817static inline void sock_orphan(struct sock *sk)
1818{
1819 write_lock_bh(&sk->sk_callback_lock);
1820 sock_set_flag(sk, SOCK_DEAD);
1821 sk_set_socket(sk, NULL);
1822 sk->sk_wq = NULL;
1823 write_unlock_bh(&sk->sk_callback_lock);
1824}
1825
1826static inline void sock_graft(struct sock *sk, struct socket *parent)
1827{
1828 WARN_ON(parent->sk);
1829 write_lock_bh(&sk->sk_callback_lock);
1830 rcu_assign_pointer(sk->sk_wq, &parent->wq);
1831 parent->sk = sk;
1832 sk_set_socket(sk, parent);
1833 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1834 security_sock_graft(sk, parent);
1835 write_unlock_bh(&sk->sk_callback_lock);
1836}
1837
1838kuid_t sock_i_uid(struct sock *sk);
1839unsigned long sock_i_ino(struct sock *sk);
1840
1841static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1842{
1843 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1844}
1845
1846static inline u32 net_tx_rndhash(void)
1847{
1848 u32 v = prandom_u32();
1849
1850 return v ?: 1;
1851}
1852
1853static inline void sk_set_txhash(struct sock *sk)
1854{
1855 sk->sk_txhash = net_tx_rndhash();
1856}
1857
1858static inline void sk_rethink_txhash(struct sock *sk)
1859{
1860 if (sk->sk_txhash)
1861 sk_set_txhash(sk);
1862}
1863
1864static inline struct dst_entry *
1865__sk_dst_get(struct sock *sk)
1866{
1867 return rcu_dereference_check(sk->sk_dst_cache,
1868 lockdep_sock_is_held(sk));
1869}
1870
1871static inline struct dst_entry *
1872sk_dst_get(struct sock *sk)
1873{
1874 struct dst_entry *dst;
1875
1876 rcu_read_lock();
1877 dst = rcu_dereference(sk->sk_dst_cache);
1878 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1879 dst = NULL;
1880 rcu_read_unlock();
1881 return dst;
1882}
1883
1884static inline void dst_negative_advice(struct sock *sk)
1885{
1886 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1887
1888 sk_rethink_txhash(sk);
1889
1890 if (dst && dst->ops->negative_advice) {
1891 ndst = dst->ops->negative_advice(dst);
1892
1893 if (ndst != dst) {
1894 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1895 sk_tx_queue_clear(sk);
1896 sk->sk_dst_pending_confirm = 0;
1897 }
1898 }
1899}
1900
1901static inline void
1902__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1903{
1904 struct dst_entry *old_dst;
1905
1906 sk_tx_queue_clear(sk);
1907 sk->sk_dst_pending_confirm = 0;
1908 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
1909 lockdep_sock_is_held(sk));
1910 rcu_assign_pointer(sk->sk_dst_cache, dst);
1911 dst_release(old_dst);
1912}
1913
1914static inline void
1915sk_dst_set(struct sock *sk, struct dst_entry *dst)
1916{
1917 struct dst_entry *old_dst;
1918
1919 sk_tx_queue_clear(sk);
1920 sk->sk_dst_pending_confirm = 0;
1921 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1922 dst_release(old_dst);
1923}
1924
1925static inline void
1926__sk_dst_reset(struct sock *sk)
1927{
1928 __sk_dst_set(sk, NULL);
1929}
1930
1931static inline void
1932sk_dst_reset(struct sock *sk)
1933{
1934 sk_dst_set(sk, NULL);
1935}
1936
1937struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1938
1939struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1940
1941static inline void sk_dst_confirm(struct sock *sk)
1942{
1943 if (!sk->sk_dst_pending_confirm)
1944 sk->sk_dst_pending_confirm = 1;
1945}
1946
1947static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
1948{
1949 if (skb_get_dst_pending_confirm(skb)) {
1950 struct sock *sk = skb->sk;
1951 unsigned long now = jiffies;
1952
1953 /* avoid dirtying neighbour */
1954 if (n->confirmed != now)
1955 n->confirmed = now;
1956 if (sk && sk->sk_dst_pending_confirm)
1957 sk->sk_dst_pending_confirm = 0;
1958 }
1959}
1960
1961bool sk_mc_loop(struct sock *sk);
1962
1963static inline bool sk_can_gso(const struct sock *sk)
1964{
1965 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1966}
1967
1968void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1969
1970static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1971{
1972 sk->sk_route_nocaps |= flags;
1973 sk->sk_route_caps &= ~flags;
1974}
1975
1976static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1977 struct iov_iter *from, char *to,
1978 int copy, int offset)
1979{
1980 if (skb->ip_summed == CHECKSUM_NONE) {
1981 __wsum csum = 0;
1982 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
1983 return -EFAULT;
1984 skb->csum = csum_block_add(skb->csum, csum, offset);
1985 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1986 if (!copy_from_iter_full_nocache(to, copy, from))
1987 return -EFAULT;
1988 } else if (!copy_from_iter_full(to, copy, from))
1989 return -EFAULT;
1990
1991 return 0;
1992}
1993
1994static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1995 struct iov_iter *from, int copy)
1996{
1997 int err, offset = skb->len;
1998
1999 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2000 copy, offset);
2001 if (err)
2002 __skb_trim(skb, offset);
2003
2004 return err;
2005}
2006
2007static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2008 struct sk_buff *skb,
2009 struct page *page,
2010 int off, int copy)
2011{
2012 int err;
2013
2014 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2015 copy, skb->len);
2016 if (err)
2017 return err;
2018
2019 skb->len += copy;
2020 skb->data_len += copy;
2021 skb->truesize += copy;
2022 sk_wmem_queued_add(sk, copy);
2023 sk_mem_charge(sk, copy);
2024 return 0;
2025}
2026
2027/**
2028 * sk_wmem_alloc_get - returns write allocations
2029 * @sk: socket
2030 *
2031 * Returns sk_wmem_alloc minus initial offset of one
2032 */
2033static inline int sk_wmem_alloc_get(const struct sock *sk)
2034{
2035 return refcount_read(&sk->sk_wmem_alloc) - 1;
2036}
2037
2038/**
2039 * sk_rmem_alloc_get - returns read allocations
2040 * @sk: socket
2041 *
2042 * Returns sk_rmem_alloc
2043 */
2044static inline int sk_rmem_alloc_get(const struct sock *sk)
2045{
2046 return atomic_read(&sk->sk_rmem_alloc);
2047}
2048
2049/**
2050 * sk_has_allocations - check if allocations are outstanding
2051 * @sk: socket
2052 *
2053 * Returns true if socket has write or read allocations
2054 */
2055static inline bool sk_has_allocations(const struct sock *sk)
2056{
2057 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2058}
2059
2060/**
2061 * skwq_has_sleeper - check if there are any waiting processes
2062 * @wq: struct socket_wq
2063 *
2064 * Returns true if socket_wq has waiting processes
2065 *
2066 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2067 * barrier call. They were added due to the race found within the tcp code.
2068 *
2069 * Consider following tcp code paths::
2070 *
2071 * CPU1 CPU2
2072 * sys_select receive packet
2073 * ... ...
2074 * __add_wait_queue update tp->rcv_nxt
2075 * ... ...
2076 * tp->rcv_nxt check sock_def_readable
2077 * ... {
2078 * schedule rcu_read_lock();
2079 * wq = rcu_dereference(sk->sk_wq);
2080 * if (wq && waitqueue_active(&wq->wait))
2081 * wake_up_interruptible(&wq->wait)
2082 * ...
2083 * }
2084 *
2085 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2086 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2087 * could then endup calling schedule and sleep forever if there are no more
2088 * data on the socket.
2089 *
2090 */
2091static inline bool skwq_has_sleeper(struct socket_wq *wq)
2092{
2093 return wq && wq_has_sleeper(&wq->wait);
2094}
2095
2096/**
2097 * sock_poll_wait - place memory barrier behind the poll_wait call.
2098 * @filp: file
2099 * @sock: socket to wait on
2100 * @p: poll_table
2101 *
2102 * See the comments in the wq_has_sleeper function.
2103 */
2104static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2105 poll_table *p)
2106{
2107 if (!poll_does_not_wait(p)) {
2108 poll_wait(filp, &sock->wq.wait, p);
2109 /* We need to be sure we are in sync with the
2110 * socket flags modification.
2111 *
2112 * This memory barrier is paired in the wq_has_sleeper.
2113 */
2114 smp_mb();
2115 }
2116}
2117
2118static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2119{
2120 if (sk->sk_txhash) {
2121 skb->l4_hash = 1;
2122 skb->hash = sk->sk_txhash;
2123 }
2124}
2125
2126void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2127
2128/*
2129 * Queue a received datagram if it will fit. Stream and sequenced
2130 * protocols can't normally use this as they need to fit buffers in
2131 * and play with them.
2132 *
2133 * Inlined as it's very short and called for pretty much every
2134 * packet ever received.
2135 */
2136static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2137{
2138 skb_orphan(skb);
2139 skb->sk = sk;
2140 skb->destructor = sock_rfree;
2141 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2142 sk_mem_charge(sk, skb->truesize);
2143}
2144
2145void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2146 unsigned long expires);
2147
2148void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2149
2150int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2151 struct sk_buff *skb, unsigned int flags,
2152 void (*destructor)(struct sock *sk,
2153 struct sk_buff *skb));
2154int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2155int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2156
2157int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2158struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2159
2160/*
2161 * Recover an error report and clear atomically
2162 */
2163
2164static inline int sock_error(struct sock *sk)
2165{
2166 int err;
2167 if (likely(!sk->sk_err))
2168 return 0;
2169 err = xchg(&sk->sk_err, 0);
2170 return -err;
2171}
2172
2173static inline unsigned long sock_wspace(struct sock *sk)
2174{
2175 int amt = 0;
2176
2177 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2178 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2179 if (amt < 0)
2180 amt = 0;
2181 }
2182 return amt;
2183}
2184
2185/* Note:
2186 * We use sk->sk_wq_raw, from contexts knowing this
2187 * pointer is not NULL and cannot disappear/change.
2188 */
2189static inline void sk_set_bit(int nr, struct sock *sk)
2190{
2191 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2192 !sock_flag(sk, SOCK_FASYNC))
2193 return;
2194
2195 set_bit(nr, &sk->sk_wq_raw->flags);
2196}
2197
2198static inline void sk_clear_bit(int nr, struct sock *sk)
2199{
2200 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2201 !sock_flag(sk, SOCK_FASYNC))
2202 return;
2203
2204 clear_bit(nr, &sk->sk_wq_raw->flags);
2205}
2206
2207static inline void sk_wake_async(const struct sock *sk, int how, int band)
2208{
2209 if (sock_flag(sk, SOCK_FASYNC)) {
2210 rcu_read_lock();
2211 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2212 rcu_read_unlock();
2213 }
2214}
2215
2216/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2217 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2218 * Note: for send buffers, TCP works better if we can build two skbs at
2219 * minimum.
2220 */
2221#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2222
2223#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2224#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2225
2226static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2227{
2228 u32 val;
2229
2230 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2231 return;
2232
2233 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2234
2235 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2236}
2237
2238struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2239 bool force_schedule);
2240
2241/**
2242 * sk_page_frag - return an appropriate page_frag
2243 * @sk: socket
2244 *
2245 * Use the per task page_frag instead of the per socket one for
2246 * optimization when we know that we're in the normal context and owns
2247 * everything that's associated with %current.
2248 *
2249 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2250 * inside other socket operations and end up recursing into sk_page_frag()
2251 * while it's already in use.
2252 */
2253static inline struct page_frag *sk_page_frag(struct sock *sk)
2254{
2255 if (gfpflags_normal_context(sk->sk_allocation))
2256 return ¤t->task_frag;
2257
2258 return &sk->sk_frag;
2259}
2260
2261bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2262
2263/*
2264 * Default write policy as shown to user space via poll/select/SIGIO
2265 */
2266static inline bool sock_writeable(const struct sock *sk)
2267{
2268 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2269}
2270
2271static inline gfp_t gfp_any(void)
2272{
2273 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2274}
2275
2276static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2277{
2278 return noblock ? 0 : sk->sk_rcvtimeo;
2279}
2280
2281static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2282{
2283 return noblock ? 0 : sk->sk_sndtimeo;
2284}
2285
2286static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2287{
2288 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2289
2290 return v ?: 1;
2291}
2292
2293/* Alas, with timeout socket operations are not restartable.
2294 * Compare this to poll().
2295 */
2296static inline int sock_intr_errno(long timeo)
2297{
2298 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2299}
2300
2301struct sock_skb_cb {
2302 u32 dropcount;
2303};
2304
2305/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2306 * using skb->cb[] would keep using it directly and utilize its
2307 * alignement guarantee.
2308 */
2309#define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
2310 sizeof(struct sock_skb_cb)))
2311
2312#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2313 SOCK_SKB_CB_OFFSET))
2314
2315#define sock_skb_cb_check_size(size) \
2316 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2317
2318static inline void
2319sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2320{
2321 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2322 atomic_read(&sk->sk_drops) : 0;
2323}
2324
2325static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2326{
2327 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2328
2329 atomic_add(segs, &sk->sk_drops);
2330}
2331
2332static inline ktime_t sock_read_timestamp(struct sock *sk)
2333{
2334#if BITS_PER_LONG==32
2335 unsigned int seq;
2336 ktime_t kt;
2337
2338 do {
2339 seq = read_seqbegin(&sk->sk_stamp_seq);
2340 kt = sk->sk_stamp;
2341 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2342
2343 return kt;
2344#else
2345 return READ_ONCE(sk->sk_stamp);
2346#endif
2347}
2348
2349static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2350{
2351#if BITS_PER_LONG==32
2352 write_seqlock(&sk->sk_stamp_seq);
2353 sk->sk_stamp = kt;
2354 write_sequnlock(&sk->sk_stamp_seq);
2355#else
2356 WRITE_ONCE(sk->sk_stamp, kt);
2357#endif
2358}
2359
2360void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2361 struct sk_buff *skb);
2362void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2363 struct sk_buff *skb);
2364
2365static inline void
2366sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2367{
2368 ktime_t kt = skb->tstamp;
2369 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2370
2371 /*
2372 * generate control messages if
2373 * - receive time stamping in software requested
2374 * - software time stamp available and wanted
2375 * - hardware time stamps available and wanted
2376 */
2377 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2378 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2379 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2380 (hwtstamps->hwtstamp &&
2381 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2382 __sock_recv_timestamp(msg, sk, skb);
2383 else
2384 sock_write_timestamp(sk, kt);
2385
2386 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2387 __sock_recv_wifi_status(msg, sk, skb);
2388}
2389
2390void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2391 struct sk_buff *skb);
2392
2393#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2394static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2395 struct sk_buff *skb)
2396{
2397#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2398 (1UL << SOCK_RCVTSTAMP))
2399#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2400 SOF_TIMESTAMPING_RAW_HARDWARE)
2401
2402 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2403 __sock_recv_ts_and_drops(msg, sk, skb);
2404 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2405 sock_write_timestamp(sk, skb->tstamp);
2406 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2407 sock_write_timestamp(sk, 0);
2408}
2409
2410void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2411
2412/**
2413 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2414 * @sk: socket sending this packet
2415 * @tsflags: timestamping flags to use
2416 * @tx_flags: completed with instructions for time stamping
2417 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2418 *
2419 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2420 */
2421static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2422 __u8 *tx_flags, __u32 *tskey)
2423{
2424 if (unlikely(tsflags)) {
2425 __sock_tx_timestamp(tsflags, tx_flags);
2426 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2427 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2428 *tskey = sk->sk_tskey++;
2429 }
2430 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2431 *tx_flags |= SKBTX_WIFI_STATUS;
2432}
2433
2434static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2435 __u8 *tx_flags)
2436{
2437 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2438}
2439
2440static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2441{
2442 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2443 &skb_shinfo(skb)->tskey);
2444}
2445
2446/**
2447 * sk_eat_skb - Release a skb if it is no longer needed
2448 * @sk: socket to eat this skb from
2449 * @skb: socket buffer to eat
2450 *
2451 * This routine must be called with interrupts disabled or with the socket
2452 * locked so that the sk_buff queue operation is ok.
2453*/
2454DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2455static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2456{
2457 __skb_unlink(skb, &sk->sk_receive_queue);
2458 if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2459 !sk->sk_rx_skb_cache) {
2460 sk->sk_rx_skb_cache = skb;
2461 skb_orphan(skb);
2462 return;
2463 }
2464 __kfree_skb(skb);
2465}
2466
2467static inline
2468struct net *sock_net(const struct sock *sk)
2469{
2470 return read_pnet(&sk->sk_net);
2471}
2472
2473static inline
2474void sock_net_set(struct sock *sk, struct net *net)
2475{
2476 write_pnet(&sk->sk_net, net);
2477}
2478
2479static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2480{
2481 if (skb->sk) {
2482 struct sock *sk = skb->sk;
2483
2484 skb->destructor = NULL;
2485 skb->sk = NULL;
2486 return sk;
2487 }
2488 return NULL;
2489}
2490
2491/* This helper checks if a socket is a full socket,
2492 * ie _not_ a timewait or request socket.
2493 */
2494static inline bool sk_fullsock(const struct sock *sk)
2495{
2496 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2497}
2498
2499/* Checks if this SKB belongs to an HW offloaded socket
2500 * and whether any SW fallbacks are required based on dev.
2501 * Check decrypted mark in case skb_orphan() cleared socket.
2502 */
2503static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2504 struct net_device *dev)
2505{
2506#ifdef CONFIG_SOCK_VALIDATE_XMIT
2507 struct sock *sk = skb->sk;
2508
2509 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2510 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2511#ifdef CONFIG_TLS_DEVICE
2512 } else if (unlikely(skb->decrypted)) {
2513 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2514 kfree_skb(skb);
2515 skb = NULL;
2516#endif
2517 }
2518#endif
2519
2520 return skb;
2521}
2522
2523/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2524 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2525 */
2526static inline bool sk_listener(const struct sock *sk)
2527{
2528 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2529}
2530
2531void sock_enable_timestamp(struct sock *sk, int flag);
2532int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2533 int type);
2534
2535bool sk_ns_capable(const struct sock *sk,
2536 struct user_namespace *user_ns, int cap);
2537bool sk_capable(const struct sock *sk, int cap);
2538bool sk_net_capable(const struct sock *sk, int cap);
2539
2540void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2541
2542/* Take into consideration the size of the struct sk_buff overhead in the
2543 * determination of these values, since that is non-constant across
2544 * platforms. This makes socket queueing behavior and performance
2545 * not depend upon such differences.
2546 */
2547#define _SK_MEM_PACKETS 256
2548#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2549#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2550#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2551
2552extern __u32 sysctl_wmem_max;
2553extern __u32 sysctl_rmem_max;
2554
2555extern int sysctl_tstamp_allow_data;
2556extern int sysctl_optmem_max;
2557
2558extern __u32 sysctl_wmem_default;
2559extern __u32 sysctl_rmem_default;
2560
2561DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2562
2563static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2564{
2565 /* Does this proto have per netns sysctl_wmem ? */
2566 if (proto->sysctl_wmem_offset)
2567 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2568
2569 return *proto->sysctl_wmem;
2570}
2571
2572static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2573{
2574 /* Does this proto have per netns sysctl_rmem ? */
2575 if (proto->sysctl_rmem_offset)
2576 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2577
2578 return *proto->sysctl_rmem;
2579}
2580
2581/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2582 * Some wifi drivers need to tweak it to get more chunks.
2583 * They can use this helper from their ndo_start_xmit()
2584 */
2585static inline void sk_pacing_shift_update(struct sock *sk, int val)
2586{
2587 if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val)
2588 return;
2589 sk->sk_pacing_shift = val;
2590}
2591
2592/* if a socket is bound to a device, check that the given device
2593 * index is either the same or that the socket is bound to an L3
2594 * master device and the given device index is also enslaved to
2595 * that L3 master
2596 */
2597static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2598{
2599 int mdif;
2600
2601 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2602 return true;
2603
2604 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2605 if (mdif && mdif == sk->sk_bound_dev_if)
2606 return true;
2607
2608 return false;
2609}
2610
2611#endif /* _SOCK_H */
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the AF_INET socket handler.
8 *
9 * Version: @(#)sock.h 1.0.4 05/13/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Corey Minyard <wf-rch!minyard@relay.EU.net>
14 * Florian La Roche <flla@stud.uni-sb.de>
15 *
16 * Fixes:
17 * Alan Cox : Volatiles in skbuff pointers. See
18 * skbuff comments. May be overdone,
19 * better to prove they can be removed
20 * than the reverse.
21 * Alan Cox : Added a zapped field for tcp to note
22 * a socket is reset and must stay shut up
23 * Alan Cox : New fields for options
24 * Pauline Middelink : identd support
25 * Alan Cox : Eliminate low level recv/recvfrom
26 * David S. Miller : New socket lookup architecture.
27 * Steve Whitehouse: Default routines for sock_ops
28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
29 * protinfo be just a void pointer, as the
30 * protocol specific parts were moved to
31 * respective headers and ipv4/v6, etc now
32 * use private slabcaches for its socks
33 * Pedro Hortas : New flags field for socket options
34 */
35#ifndef _SOCK_H
36#define _SOCK_H
37
38#include <linux/hardirq.h>
39#include <linux/kernel.h>
40#include <linux/list.h>
41#include <linux/list_nulls.h>
42#include <linux/timer.h>
43#include <linux/cache.h>
44#include <linux/bitops.h>
45#include <linux/lockdep.h>
46#include <linux/netdevice.h>
47#include <linux/skbuff.h> /* struct sk_buff */
48#include <linux/mm.h>
49#include <linux/security.h>
50#include <linux/slab.h>
51#include <linux/uaccess.h>
52#include <linux/page_counter.h>
53#include <linux/memcontrol.h>
54#include <linux/static_key.h>
55#include <linux/sched.h>
56#include <linux/wait.h>
57#include <linux/cgroup-defs.h>
58#include <linux/rbtree.h>
59#include <linux/filter.h>
60#include <linux/rculist_nulls.h>
61#include <linux/poll.h>
62#include <linux/sockptr.h>
63#include <linux/indirect_call_wrapper.h>
64#include <linux/atomic.h>
65#include <linux/refcount.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
72/*
73 * This structure really needs to be cleaned up.
74 * Most of it is for TCP, and not used by any of
75 * the other protocols.
76 */
77
78/* Define this to get the SOCK_DBG debugging facility. */
79#define SOCK_DEBUGGING
80#ifdef SOCK_DEBUGGING
81#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
82 printk(KERN_DEBUG msg); } while (0)
83#else
84/* Validate arguments and do nothing */
85static inline __printf(2, 3)
86void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
87{
88}
89#endif
90
91/* This is the per-socket lock. The spinlock provides a synchronization
92 * between user contexts and software interrupt processing, whereas the
93 * mini-semaphore synchronizes multiple users amongst themselves.
94 */
95typedef struct {
96 spinlock_t slock;
97 int owned;
98 wait_queue_head_t wq;
99 /*
100 * We express the mutex-alike socket_lock semantics
101 * to the lock validator by explicitly managing
102 * the slock as a lock variant (in addition to
103 * the slock itself):
104 */
105#ifdef CONFIG_DEBUG_LOCK_ALLOC
106 struct lockdep_map dep_map;
107#endif
108} socket_lock_t;
109
110struct sock;
111struct proto;
112struct net;
113
114typedef __u32 __bitwise __portpair;
115typedef __u64 __bitwise __addrpair;
116
117/**
118 * struct sock_common - minimal network layer representation of sockets
119 * @skc_daddr: Foreign IPv4 addr
120 * @skc_rcv_saddr: Bound local IPv4 addr
121 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
122 * @skc_hash: hash value used with various protocol lookup tables
123 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
124 * @skc_dport: placeholder for inet_dport/tw_dport
125 * @skc_num: placeholder for inet_num/tw_num
126 * @skc_portpair: __u32 union of @skc_dport & @skc_num
127 * @skc_family: network address family
128 * @skc_state: Connection state
129 * @skc_reuse: %SO_REUSEADDR setting
130 * @skc_reuseport: %SO_REUSEPORT setting
131 * @skc_ipv6only: socket is IPV6 only
132 * @skc_net_refcnt: socket is using net ref counting
133 * @skc_bound_dev_if: bound device index if != 0
134 * @skc_bind_node: bind hash linkage for various protocol lookup tables
135 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
136 * @skc_prot: protocol handlers inside a network family
137 * @skc_net: reference to the network namespace of this socket
138 * @skc_v6_daddr: IPV6 destination address
139 * @skc_v6_rcv_saddr: IPV6 source address
140 * @skc_cookie: socket's cookie value
141 * @skc_node: main hash linkage for various protocol lookup tables
142 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
143 * @skc_tx_queue_mapping: tx queue number for this connection
144 * @skc_rx_queue_mapping: rx queue number for this connection
145 * @skc_flags: place holder for sk_flags
146 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
147 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
148 * @skc_listener: connection request listener socket (aka rsk_listener)
149 * [union with @skc_flags]
150 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
151 * [union with @skc_flags]
152 * @skc_incoming_cpu: record/match cpu processing incoming packets
153 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
154 * [union with @skc_incoming_cpu]
155 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
156 * [union with @skc_incoming_cpu]
157 * @skc_refcnt: reference count
158 *
159 * This is the minimal network layer representation of sockets, the header
160 * for struct sock and struct inet_timewait_sock.
161 */
162struct sock_common {
163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
164 * address on 64bit arches : cf INET_MATCH()
165 */
166 union {
167 __addrpair skc_addrpair;
168 struct {
169 __be32 skc_daddr;
170 __be32 skc_rcv_saddr;
171 };
172 };
173 union {
174 unsigned int skc_hash;
175 __u16 skc_u16hashes[2];
176 };
177 /* skc_dport && skc_num must be grouped as well */
178 union {
179 __portpair skc_portpair;
180 struct {
181 __be16 skc_dport;
182 __u16 skc_num;
183 };
184 };
185
186 unsigned short skc_family;
187 volatile unsigned char skc_state;
188 unsigned char skc_reuse:4;
189 unsigned char skc_reuseport:1;
190 unsigned char skc_ipv6only:1;
191 unsigned char skc_net_refcnt:1;
192 int skc_bound_dev_if;
193 union {
194 struct hlist_node skc_bind_node;
195 struct hlist_node skc_portaddr_node;
196 };
197 struct proto *skc_prot;
198 possible_net_t skc_net;
199
200#if IS_ENABLED(CONFIG_IPV6)
201 struct in6_addr skc_v6_daddr;
202 struct in6_addr skc_v6_rcv_saddr;
203#endif
204
205 atomic64_t skc_cookie;
206
207 /* following fields are padding to force
208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
209 * assuming IPV6 is enabled. We use this padding differently
210 * for different kind of 'sockets'
211 */
212 union {
213 unsigned long skc_flags;
214 struct sock *skc_listener; /* request_sock */
215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
216 };
217 /*
218 * fields between dontcopy_begin/dontcopy_end
219 * are not copied in sock_copy()
220 */
221 /* private: */
222 int skc_dontcopy_begin[0];
223 /* public: */
224 union {
225 struct hlist_node skc_node;
226 struct hlist_nulls_node skc_nulls_node;
227 };
228 unsigned short skc_tx_queue_mapping;
229#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
230 unsigned short skc_rx_queue_mapping;
231#endif
232 union {
233 int skc_incoming_cpu;
234 u32 skc_rcv_wnd;
235 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
236 };
237
238 refcount_t skc_refcnt;
239 /* private: */
240 int skc_dontcopy_end[0];
241 union {
242 u32 skc_rxhash;
243 u32 skc_window_clamp;
244 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
245 };
246 /* public: */
247};
248
249struct bpf_local_storage;
250
251/**
252 * struct sock - network layer representation of sockets
253 * @__sk_common: shared layout with inet_timewait_sock
254 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
255 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
256 * @sk_lock: synchronizer
257 * @sk_kern_sock: True if sock is using kernel lock classes
258 * @sk_rcvbuf: size of receive buffer in bytes
259 * @sk_wq: sock wait queue and async head
260 * @sk_rx_dst: receive input route used by early demux
261 * @sk_dst_cache: destination cache
262 * @sk_dst_pending_confirm: need to confirm neighbour
263 * @sk_policy: flow policy
264 * @sk_rx_skb_cache: cache copy of recently accessed RX skb
265 * @sk_receive_queue: incoming packets
266 * @sk_wmem_alloc: transmit queue bytes committed
267 * @sk_tsq_flags: TCP Small Queues flags
268 * @sk_write_queue: Packet sending queue
269 * @sk_omem_alloc: "o" is "option" or "other"
270 * @sk_wmem_queued: persistent queue size
271 * @sk_forward_alloc: space allocated forward
272 * @sk_napi_id: id of the last napi context to receive data for sk
273 * @sk_ll_usec: usecs to busypoll when there is no data
274 * @sk_allocation: allocation mode
275 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
276 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
277 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
278 * @sk_sndbuf: size of send buffer in bytes
279 * @__sk_flags_offset: empty field used to determine location of bitfield
280 * @sk_padding: unused element for alignment
281 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
282 * @sk_no_check_rx: allow zero checksum in RX packets
283 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
284 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
285 * @sk_route_forced_caps: static, forced route capabilities
286 * (set in tcp_init_sock())
287 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
288 * @sk_gso_max_size: Maximum GSO segment size to build
289 * @sk_gso_max_segs: Maximum number of GSO segments
290 * @sk_pacing_shift: scaling factor for TCP Small Queues
291 * @sk_lingertime: %SO_LINGER l_linger setting
292 * @sk_backlog: always used with the per-socket spinlock held
293 * @sk_callback_lock: used with the callbacks in the end of this struct
294 * @sk_error_queue: rarely used
295 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
296 * IPV6_ADDRFORM for instance)
297 * @sk_err: last error
298 * @sk_err_soft: errors that don't cause failure but are the cause of a
299 * persistent failure not just 'timed out'
300 * @sk_drops: raw/udp drops counter
301 * @sk_ack_backlog: current listen backlog
302 * @sk_max_ack_backlog: listen backlog set in listen()
303 * @sk_uid: user id of owner
304 * @sk_prefer_busy_poll: prefer busypolling over softirq processing
305 * @sk_busy_poll_budget: napi processing budget when busypolling
306 * @sk_priority: %SO_PRIORITY setting
307 * @sk_type: socket type (%SOCK_STREAM, etc)
308 * @sk_protocol: which protocol this socket belongs in this network family
309 * @sk_peer_pid: &struct pid for this socket's peer
310 * @sk_peer_cred: %SO_PEERCRED setting
311 * @sk_rcvlowat: %SO_RCVLOWAT setting
312 * @sk_rcvtimeo: %SO_RCVTIMEO setting
313 * @sk_sndtimeo: %SO_SNDTIMEO setting
314 * @sk_txhash: computed flow hash for use on transmit
315 * @sk_filter: socket filtering instructions
316 * @sk_timer: sock cleanup timer
317 * @sk_stamp: time stamp of last packet received
318 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
319 * @sk_tsflags: SO_TIMESTAMPING flags
320 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
321 * for timestamping
322 * @sk_tskey: counter to disambiguate concurrent tstamp requests
323 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
324 * @sk_socket: Identd and reporting IO signals
325 * @sk_user_data: RPC layer private data
326 * @sk_frag: cached page frag
327 * @sk_peek_off: current peek_offset value
328 * @sk_send_head: front of stuff to transmit
329 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
330 * @sk_tx_skb_cache: cache copy of recently accessed TX skb
331 * @sk_security: used by security modules
332 * @sk_mark: generic packet mark
333 * @sk_cgrp_data: cgroup data for this cgroup
334 * @sk_memcg: this socket's memory cgroup association
335 * @sk_write_pending: a write to stream socket waits to start
336 * @sk_state_change: callback to indicate change in the state of the sock
337 * @sk_data_ready: callback to indicate there is data to be processed
338 * @sk_write_space: callback to indicate there is bf sending space available
339 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
340 * @sk_backlog_rcv: callback to process the backlog
341 * @sk_validate_xmit_skb: ptr to an optional validate function
342 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
343 * @sk_reuseport_cb: reuseport group container
344 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
345 * @sk_rcu: used during RCU grace period
346 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
347 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
348 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME
349 * @sk_txtime_unused: unused txtime flags
350 */
351struct sock {
352 /*
353 * Now struct inet_timewait_sock also uses sock_common, so please just
354 * don't add nothing before this first member (__sk_common) --acme
355 */
356 struct sock_common __sk_common;
357#define sk_node __sk_common.skc_node
358#define sk_nulls_node __sk_common.skc_nulls_node
359#define sk_refcnt __sk_common.skc_refcnt
360#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
361#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
362#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
363#endif
364
365#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
366#define sk_dontcopy_end __sk_common.skc_dontcopy_end
367#define sk_hash __sk_common.skc_hash
368#define sk_portpair __sk_common.skc_portpair
369#define sk_num __sk_common.skc_num
370#define sk_dport __sk_common.skc_dport
371#define sk_addrpair __sk_common.skc_addrpair
372#define sk_daddr __sk_common.skc_daddr
373#define sk_rcv_saddr __sk_common.skc_rcv_saddr
374#define sk_family __sk_common.skc_family
375#define sk_state __sk_common.skc_state
376#define sk_reuse __sk_common.skc_reuse
377#define sk_reuseport __sk_common.skc_reuseport
378#define sk_ipv6only __sk_common.skc_ipv6only
379#define sk_net_refcnt __sk_common.skc_net_refcnt
380#define sk_bound_dev_if __sk_common.skc_bound_dev_if
381#define sk_bind_node __sk_common.skc_bind_node
382#define sk_prot __sk_common.skc_prot
383#define sk_net __sk_common.skc_net
384#define sk_v6_daddr __sk_common.skc_v6_daddr
385#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
386#define sk_cookie __sk_common.skc_cookie
387#define sk_incoming_cpu __sk_common.skc_incoming_cpu
388#define sk_flags __sk_common.skc_flags
389#define sk_rxhash __sk_common.skc_rxhash
390
391 socket_lock_t sk_lock;
392 atomic_t sk_drops;
393 int sk_rcvlowat;
394 struct sk_buff_head sk_error_queue;
395 struct sk_buff *sk_rx_skb_cache;
396 struct sk_buff_head sk_receive_queue;
397 /*
398 * The backlog queue is special, it is always used with
399 * the per-socket spinlock held and requires low latency
400 * access. Therefore we special case it's implementation.
401 * Note : rmem_alloc is in this structure to fill a hole
402 * on 64bit arches, not because its logically part of
403 * backlog.
404 */
405 struct {
406 atomic_t rmem_alloc;
407 int len;
408 struct sk_buff *head;
409 struct sk_buff *tail;
410 } sk_backlog;
411#define sk_rmem_alloc sk_backlog.rmem_alloc
412
413 int sk_forward_alloc;
414#ifdef CONFIG_NET_RX_BUSY_POLL
415 unsigned int sk_ll_usec;
416 /* ===== mostly read cache line ===== */
417 unsigned int sk_napi_id;
418#endif
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#ifdef CONFIG_XFRM
429 struct xfrm_policy __rcu *sk_policy[2];
430#endif
431 struct dst_entry *sk_rx_dst;
432 struct dst_entry __rcu *sk_dst_cache;
433 atomic_t sk_omem_alloc;
434 int sk_sndbuf;
435
436 /* ===== cache line for TX ===== */
437 int sk_wmem_queued;
438 refcount_t sk_wmem_alloc;
439 unsigned long sk_tsq_flags;
440 union {
441 struct sk_buff *sk_send_head;
442 struct rb_root tcp_rtx_queue;
443 };
444 struct sk_buff *sk_tx_skb_cache;
445 struct sk_buff_head sk_write_queue;
446 __s32 sk_peek_off;
447 int sk_write_pending;
448 __u32 sk_dst_pending_confirm;
449 u32 sk_pacing_status; /* see enum sk_pacing */
450 long sk_sndtimeo;
451 struct timer_list sk_timer;
452 __u32 sk_priority;
453 __u32 sk_mark;
454 unsigned long sk_pacing_rate; /* bytes per second */
455 unsigned long sk_max_pacing_rate;
456 struct page_frag sk_frag;
457 netdev_features_t sk_route_caps;
458 netdev_features_t sk_route_nocaps;
459 netdev_features_t sk_route_forced_caps;
460 int sk_gso_type;
461 unsigned int sk_gso_max_size;
462 gfp_t sk_allocation;
463 __u32 sk_txhash;
464
465 /*
466 * Because of non atomicity rules, all
467 * changes are protected by socket lock.
468 */
469 u8 sk_padding : 1,
470 sk_kern_sock : 1,
471 sk_no_check_tx : 1,
472 sk_no_check_rx : 1,
473 sk_userlocks : 4;
474 u8 sk_pacing_shift;
475 u16 sk_type;
476 u16 sk_protocol;
477 u16 sk_gso_max_segs;
478 unsigned long sk_lingertime;
479 struct proto *sk_prot_creator;
480 rwlock_t sk_callback_lock;
481 int sk_err,
482 sk_err_soft;
483 u32 sk_ack_backlog;
484 u32 sk_max_ack_backlog;
485 kuid_t sk_uid;
486#ifdef CONFIG_NET_RX_BUSY_POLL
487 u8 sk_prefer_busy_poll;
488 u16 sk_busy_poll_budget;
489#endif
490 spinlock_t sk_peer_lock;
491 struct pid *sk_peer_pid;
492 const struct cred *sk_peer_cred;
493
494 long sk_rcvtimeo;
495 ktime_t sk_stamp;
496#if BITS_PER_LONG==32
497 seqlock_t sk_stamp_seq;
498#endif
499 u16 sk_tsflags;
500 int sk_bind_phc;
501 u8 sk_shutdown;
502 u32 sk_tskey;
503 atomic_t sk_zckey;
504
505 u8 sk_clockid;
506 u8 sk_txtime_deadline_mode : 1,
507 sk_txtime_report_errors : 1,
508 sk_txtime_unused : 6;
509
510 struct socket *sk_socket;
511 void *sk_user_data;
512#ifdef CONFIG_SECURITY
513 void *sk_security;
514#endif
515 struct sock_cgroup_data sk_cgrp_data;
516 struct mem_cgroup *sk_memcg;
517 void (*sk_state_change)(struct sock *sk);
518 void (*sk_data_ready)(struct sock *sk);
519 void (*sk_write_space)(struct sock *sk);
520 void (*sk_error_report)(struct sock *sk);
521 int (*sk_backlog_rcv)(struct sock *sk,
522 struct sk_buff *skb);
523#ifdef CONFIG_SOCK_VALIDATE_XMIT
524 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
525 struct net_device *dev,
526 struct sk_buff *skb);
527#endif
528 void (*sk_destruct)(struct sock *sk);
529 struct sock_reuseport __rcu *sk_reuseport_cb;
530#ifdef CONFIG_BPF_SYSCALL
531 struct bpf_local_storage __rcu *sk_bpf_storage;
532#endif
533 struct rcu_head sk_rcu;
534};
535
536enum sk_pacing {
537 SK_PACING_NONE = 0,
538 SK_PACING_NEEDED = 1,
539 SK_PACING_FQ = 2,
540};
541
542/* Pointer stored in sk_user_data might not be suitable for copying
543 * when cloning the socket. For instance, it can point to a reference
544 * counted object. sk_user_data bottom bit is set if pointer must not
545 * be copied.
546 */
547#define SK_USER_DATA_NOCOPY 1UL
548#define SK_USER_DATA_BPF 2UL /* Managed by BPF */
549#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
550
551/**
552 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
553 * @sk: socket
554 */
555static inline bool sk_user_data_is_nocopy(const struct sock *sk)
556{
557 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
558}
559
560#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
561
562#define rcu_dereference_sk_user_data(sk) \
563({ \
564 void *__tmp = rcu_dereference(__sk_user_data((sk))); \
565 (void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \
566})
567#define rcu_assign_sk_user_data(sk, ptr) \
568({ \
569 uintptr_t __tmp = (uintptr_t)(ptr); \
570 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
571 rcu_assign_pointer(__sk_user_data((sk)), __tmp); \
572})
573#define rcu_assign_sk_user_data_nocopy(sk, ptr) \
574({ \
575 uintptr_t __tmp = (uintptr_t)(ptr); \
576 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
577 rcu_assign_pointer(__sk_user_data((sk)), \
578 __tmp | SK_USER_DATA_NOCOPY); \
579})
580
581/*
582 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
583 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
584 * on a socket means that the socket will reuse everybody else's port
585 * without looking at the other's sk_reuse value.
586 */
587
588#define SK_NO_REUSE 0
589#define SK_CAN_REUSE 1
590#define SK_FORCE_REUSE 2
591
592int sk_set_peek_off(struct sock *sk, int val);
593
594static inline int sk_peek_offset(struct sock *sk, int flags)
595{
596 if (unlikely(flags & MSG_PEEK)) {
597 return READ_ONCE(sk->sk_peek_off);
598 }
599
600 return 0;
601}
602
603static inline void sk_peek_offset_bwd(struct sock *sk, int val)
604{
605 s32 off = READ_ONCE(sk->sk_peek_off);
606
607 if (unlikely(off >= 0)) {
608 off = max_t(s32, off - val, 0);
609 WRITE_ONCE(sk->sk_peek_off, off);
610 }
611}
612
613static inline void sk_peek_offset_fwd(struct sock *sk, int val)
614{
615 sk_peek_offset_bwd(sk, -val);
616}
617
618/*
619 * Hashed lists helper routines
620 */
621static inline struct sock *sk_entry(const struct hlist_node *node)
622{
623 return hlist_entry(node, struct sock, sk_node);
624}
625
626static inline struct sock *__sk_head(const struct hlist_head *head)
627{
628 return hlist_entry(head->first, struct sock, sk_node);
629}
630
631static inline struct sock *sk_head(const struct hlist_head *head)
632{
633 return hlist_empty(head) ? NULL : __sk_head(head);
634}
635
636static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
637{
638 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
639}
640
641static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
642{
643 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
644}
645
646static inline struct sock *sk_next(const struct sock *sk)
647{
648 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
649}
650
651static inline struct sock *sk_nulls_next(const struct sock *sk)
652{
653 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
654 hlist_nulls_entry(sk->sk_nulls_node.next,
655 struct sock, sk_nulls_node) :
656 NULL;
657}
658
659static inline bool sk_unhashed(const struct sock *sk)
660{
661 return hlist_unhashed(&sk->sk_node);
662}
663
664static inline bool sk_hashed(const struct sock *sk)
665{
666 return !sk_unhashed(sk);
667}
668
669static inline void sk_node_init(struct hlist_node *node)
670{
671 node->pprev = NULL;
672}
673
674static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
675{
676 node->pprev = NULL;
677}
678
679static inline void __sk_del_node(struct sock *sk)
680{
681 __hlist_del(&sk->sk_node);
682}
683
684/* NB: equivalent to hlist_del_init_rcu */
685static inline bool __sk_del_node_init(struct sock *sk)
686{
687 if (sk_hashed(sk)) {
688 __sk_del_node(sk);
689 sk_node_init(&sk->sk_node);
690 return true;
691 }
692 return false;
693}
694
695/* Grab socket reference count. This operation is valid only
696 when sk is ALREADY grabbed f.e. it is found in hash table
697 or a list and the lookup is made under lock preventing hash table
698 modifications.
699 */
700
701static __always_inline void sock_hold(struct sock *sk)
702{
703 refcount_inc(&sk->sk_refcnt);
704}
705
706/* Ungrab socket in the context, which assumes that socket refcnt
707 cannot hit zero, f.e. it is true in context of any socketcall.
708 */
709static __always_inline void __sock_put(struct sock *sk)
710{
711 refcount_dec(&sk->sk_refcnt);
712}
713
714static inline bool sk_del_node_init(struct sock *sk)
715{
716 bool rc = __sk_del_node_init(sk);
717
718 if (rc) {
719 /* paranoid for a while -acme */
720 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
721 __sock_put(sk);
722 }
723 return rc;
724}
725#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
726
727static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
728{
729 if (sk_hashed(sk)) {
730 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
731 return true;
732 }
733 return false;
734}
735
736static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
737{
738 bool rc = __sk_nulls_del_node_init_rcu(sk);
739
740 if (rc) {
741 /* paranoid for a while -acme */
742 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
743 __sock_put(sk);
744 }
745 return rc;
746}
747
748static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
749{
750 hlist_add_head(&sk->sk_node, list);
751}
752
753static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
754{
755 sock_hold(sk);
756 __sk_add_node(sk, list);
757}
758
759static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
760{
761 sock_hold(sk);
762 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
763 sk->sk_family == AF_INET6)
764 hlist_add_tail_rcu(&sk->sk_node, list);
765 else
766 hlist_add_head_rcu(&sk->sk_node, list);
767}
768
769static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
770{
771 sock_hold(sk);
772 hlist_add_tail_rcu(&sk->sk_node, list);
773}
774
775static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
776{
777 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
778}
779
780static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
781{
782 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
783}
784
785static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
786{
787 sock_hold(sk);
788 __sk_nulls_add_node_rcu(sk, list);
789}
790
791static inline void __sk_del_bind_node(struct sock *sk)
792{
793 __hlist_del(&sk->sk_bind_node);
794}
795
796static inline void sk_add_bind_node(struct sock *sk,
797 struct hlist_head *list)
798{
799 hlist_add_head(&sk->sk_bind_node, list);
800}
801
802#define sk_for_each(__sk, list) \
803 hlist_for_each_entry(__sk, list, sk_node)
804#define sk_for_each_rcu(__sk, list) \
805 hlist_for_each_entry_rcu(__sk, list, sk_node)
806#define sk_nulls_for_each(__sk, node, list) \
807 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
808#define sk_nulls_for_each_rcu(__sk, node, list) \
809 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
810#define sk_for_each_from(__sk) \
811 hlist_for_each_entry_from(__sk, sk_node)
812#define sk_nulls_for_each_from(__sk, node) \
813 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
814 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
815#define sk_for_each_safe(__sk, tmp, list) \
816 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
817#define sk_for_each_bound(__sk, list) \
818 hlist_for_each_entry(__sk, list, sk_bind_node)
819
820/**
821 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
822 * @tpos: the type * to use as a loop cursor.
823 * @pos: the &struct hlist_node to use as a loop cursor.
824 * @head: the head for your list.
825 * @offset: offset of hlist_node within the struct.
826 *
827 */
828#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
829 for (pos = rcu_dereference(hlist_first_rcu(head)); \
830 pos != NULL && \
831 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
832 pos = rcu_dereference(hlist_next_rcu(pos)))
833
834static inline struct user_namespace *sk_user_ns(struct sock *sk)
835{
836 /* Careful only use this in a context where these parameters
837 * can not change and must all be valid, such as recvmsg from
838 * userspace.
839 */
840 return sk->sk_socket->file->f_cred->user_ns;
841}
842
843/* Sock flags */
844enum sock_flags {
845 SOCK_DEAD,
846 SOCK_DONE,
847 SOCK_URGINLINE,
848 SOCK_KEEPOPEN,
849 SOCK_LINGER,
850 SOCK_DESTROY,
851 SOCK_BROADCAST,
852 SOCK_TIMESTAMP,
853 SOCK_ZAPPED,
854 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
855 SOCK_DBG, /* %SO_DEBUG setting */
856 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
857 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
858 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
859 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
860 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
861 SOCK_FASYNC, /* fasync() active */
862 SOCK_RXQ_OVFL,
863 SOCK_ZEROCOPY, /* buffers from userspace */
864 SOCK_WIFI_STATUS, /* push wifi status to userspace */
865 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
866 * Will use last 4 bytes of packet sent from
867 * user-space instead.
868 */
869 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
870 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
871 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
872 SOCK_TXTIME,
873 SOCK_XDP, /* XDP is attached */
874 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
875};
876
877#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
878
879static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
880{
881 nsk->sk_flags = osk->sk_flags;
882}
883
884static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
885{
886 __set_bit(flag, &sk->sk_flags);
887}
888
889static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
890{
891 __clear_bit(flag, &sk->sk_flags);
892}
893
894static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
895 int valbool)
896{
897 if (valbool)
898 sock_set_flag(sk, bit);
899 else
900 sock_reset_flag(sk, bit);
901}
902
903static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
904{
905 return test_bit(flag, &sk->sk_flags);
906}
907
908#ifdef CONFIG_NET
909DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
910static inline int sk_memalloc_socks(void)
911{
912 return static_branch_unlikely(&memalloc_socks_key);
913}
914
915void __receive_sock(struct file *file);
916#else
917
918static inline int sk_memalloc_socks(void)
919{
920 return 0;
921}
922
923static inline void __receive_sock(struct file *file)
924{ }
925#endif
926
927static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
928{
929 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
930}
931
932static inline void sk_acceptq_removed(struct sock *sk)
933{
934 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
935}
936
937static inline void sk_acceptq_added(struct sock *sk)
938{
939 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
940}
941
942/* Note: If you think the test should be:
943 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
944 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
945 */
946static inline bool sk_acceptq_is_full(const struct sock *sk)
947{
948 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
949}
950
951/*
952 * Compute minimal free write space needed to queue new packets.
953 */
954static inline int sk_stream_min_wspace(const struct sock *sk)
955{
956 return READ_ONCE(sk->sk_wmem_queued) >> 1;
957}
958
959static inline int sk_stream_wspace(const struct sock *sk)
960{
961 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
962}
963
964static inline void sk_wmem_queued_add(struct sock *sk, int val)
965{
966 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
967}
968
969void sk_stream_write_space(struct sock *sk);
970
971/* OOB backlog add */
972static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
973{
974 /* dont let skb dst not refcounted, we are going to leave rcu lock */
975 skb_dst_force(skb);
976
977 if (!sk->sk_backlog.tail)
978 WRITE_ONCE(sk->sk_backlog.head, skb);
979 else
980 sk->sk_backlog.tail->next = skb;
981
982 WRITE_ONCE(sk->sk_backlog.tail, skb);
983 skb->next = NULL;
984}
985
986/*
987 * Take into account size of receive queue and backlog queue
988 * Do not take into account this skb truesize,
989 * to allow even a single big packet to come.
990 */
991static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
992{
993 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
994
995 return qsize > limit;
996}
997
998/* The per-socket spinlock must be held here. */
999static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1000 unsigned int limit)
1001{
1002 if (sk_rcvqueues_full(sk, limit))
1003 return -ENOBUFS;
1004
1005 /*
1006 * If the skb was allocated from pfmemalloc reserves, only
1007 * allow SOCK_MEMALLOC sockets to use it as this socket is
1008 * helping free memory
1009 */
1010 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1011 return -ENOMEM;
1012
1013 __sk_add_backlog(sk, skb);
1014 sk->sk_backlog.len += skb->truesize;
1015 return 0;
1016}
1017
1018int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1019
1020static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1021{
1022 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1023 return __sk_backlog_rcv(sk, skb);
1024
1025 return sk->sk_backlog_rcv(sk, skb);
1026}
1027
1028static inline void sk_incoming_cpu_update(struct sock *sk)
1029{
1030 int cpu = raw_smp_processor_id();
1031
1032 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1033 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1034}
1035
1036static inline void sock_rps_record_flow_hash(__u32 hash)
1037{
1038#ifdef CONFIG_RPS
1039 struct rps_sock_flow_table *sock_flow_table;
1040
1041 rcu_read_lock();
1042 sock_flow_table = rcu_dereference(rps_sock_flow_table);
1043 rps_record_sock_flow(sock_flow_table, hash);
1044 rcu_read_unlock();
1045#endif
1046}
1047
1048static inline void sock_rps_record_flow(const struct sock *sk)
1049{
1050#ifdef CONFIG_RPS
1051 if (static_branch_unlikely(&rfs_needed)) {
1052 /* Reading sk->sk_rxhash might incur an expensive cache line
1053 * miss.
1054 *
1055 * TCP_ESTABLISHED does cover almost all states where RFS
1056 * might be useful, and is cheaper [1] than testing :
1057 * IPv4: inet_sk(sk)->inet_daddr
1058 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1059 * OR an additional socket flag
1060 * [1] : sk_state and sk_prot are in the same cache line.
1061 */
1062 if (sk->sk_state == TCP_ESTABLISHED)
1063 sock_rps_record_flow_hash(sk->sk_rxhash);
1064 }
1065#endif
1066}
1067
1068static inline void sock_rps_save_rxhash(struct sock *sk,
1069 const struct sk_buff *skb)
1070{
1071#ifdef CONFIG_RPS
1072 if (unlikely(sk->sk_rxhash != skb->hash))
1073 sk->sk_rxhash = skb->hash;
1074#endif
1075}
1076
1077static inline void sock_rps_reset_rxhash(struct sock *sk)
1078{
1079#ifdef CONFIG_RPS
1080 sk->sk_rxhash = 0;
1081#endif
1082}
1083
1084#define sk_wait_event(__sk, __timeo, __condition, __wait) \
1085 ({ int __rc; \
1086 release_sock(__sk); \
1087 __rc = __condition; \
1088 if (!__rc) { \
1089 *(__timeo) = wait_woken(__wait, \
1090 TASK_INTERRUPTIBLE, \
1091 *(__timeo)); \
1092 } \
1093 sched_annotate_sleep(); \
1094 lock_sock(__sk); \
1095 __rc = __condition; \
1096 __rc; \
1097 })
1098
1099int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1100int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1101void sk_stream_wait_close(struct sock *sk, long timeo_p);
1102int sk_stream_error(struct sock *sk, int flags, int err);
1103void sk_stream_kill_queues(struct sock *sk);
1104void sk_set_memalloc(struct sock *sk);
1105void sk_clear_memalloc(struct sock *sk);
1106
1107void __sk_flush_backlog(struct sock *sk);
1108
1109static inline bool sk_flush_backlog(struct sock *sk)
1110{
1111 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1112 __sk_flush_backlog(sk);
1113 return true;
1114 }
1115 return false;
1116}
1117
1118int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1119
1120struct request_sock_ops;
1121struct timewait_sock_ops;
1122struct inet_hashinfo;
1123struct raw_hashinfo;
1124struct smc_hashinfo;
1125struct module;
1126struct sk_psock;
1127
1128/*
1129 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1130 * un-modified. Special care is taken when initializing object to zero.
1131 */
1132static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1133{
1134 if (offsetof(struct sock, sk_node.next) != 0)
1135 memset(sk, 0, offsetof(struct sock, sk_node.next));
1136 memset(&sk->sk_node.pprev, 0,
1137 size - offsetof(struct sock, sk_node.pprev));
1138}
1139
1140/* Networking protocol blocks we attach to sockets.
1141 * socket layer -> transport layer interface
1142 */
1143struct proto {
1144 void (*close)(struct sock *sk,
1145 long timeout);
1146 int (*pre_connect)(struct sock *sk,
1147 struct sockaddr *uaddr,
1148 int addr_len);
1149 int (*connect)(struct sock *sk,
1150 struct sockaddr *uaddr,
1151 int addr_len);
1152 int (*disconnect)(struct sock *sk, int flags);
1153
1154 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1155 bool kern);
1156
1157 int (*ioctl)(struct sock *sk, int cmd,
1158 unsigned long arg);
1159 int (*init)(struct sock *sk);
1160 void (*destroy)(struct sock *sk);
1161 void (*shutdown)(struct sock *sk, int how);
1162 int (*setsockopt)(struct sock *sk, int level,
1163 int optname, sockptr_t optval,
1164 unsigned int optlen);
1165 int (*getsockopt)(struct sock *sk, int level,
1166 int optname, char __user *optval,
1167 int __user *option);
1168 void (*keepalive)(struct sock *sk, int valbool);
1169#ifdef CONFIG_COMPAT
1170 int (*compat_ioctl)(struct sock *sk,
1171 unsigned int cmd, unsigned long arg);
1172#endif
1173 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1174 size_t len);
1175 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1176 size_t len, int noblock, int flags,
1177 int *addr_len);
1178 int (*sendpage)(struct sock *sk, struct page *page,
1179 int offset, size_t size, int flags);
1180 int (*bind)(struct sock *sk,
1181 struct sockaddr *addr, int addr_len);
1182 int (*bind_add)(struct sock *sk,
1183 struct sockaddr *addr, int addr_len);
1184
1185 int (*backlog_rcv) (struct sock *sk,
1186 struct sk_buff *skb);
1187 bool (*bpf_bypass_getsockopt)(int level,
1188 int optname);
1189
1190 void (*release_cb)(struct sock *sk);
1191
1192 /* Keeping track of sk's, looking them up, and port selection methods. */
1193 int (*hash)(struct sock *sk);
1194 void (*unhash)(struct sock *sk);
1195 void (*rehash)(struct sock *sk);
1196 int (*get_port)(struct sock *sk, unsigned short snum);
1197#ifdef CONFIG_BPF_SYSCALL
1198 int (*psock_update_sk_prot)(struct sock *sk,
1199 struct sk_psock *psock,
1200 bool restore);
1201#endif
1202
1203 /* Keeping track of sockets in use */
1204#ifdef CONFIG_PROC_FS
1205 unsigned int inuse_idx;
1206#endif
1207
1208 bool (*stream_memory_free)(const struct sock *sk, int wake);
1209 bool (*stream_memory_read)(const struct sock *sk);
1210 /* Memory pressure */
1211 void (*enter_memory_pressure)(struct sock *sk);
1212 void (*leave_memory_pressure)(struct sock *sk);
1213 atomic_long_t *memory_allocated; /* Current allocated memory. */
1214 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1215 /*
1216 * Pressure flag: try to collapse.
1217 * Technical note: it is used by multiple contexts non atomically.
1218 * All the __sk_mem_schedule() is of this nature: accounting
1219 * is strict, actions are advisory and have some latency.
1220 */
1221 unsigned long *memory_pressure;
1222 long *sysctl_mem;
1223
1224 int *sysctl_wmem;
1225 int *sysctl_rmem;
1226 u32 sysctl_wmem_offset;
1227 u32 sysctl_rmem_offset;
1228
1229 int max_header;
1230 bool no_autobind;
1231
1232 struct kmem_cache *slab;
1233 unsigned int obj_size;
1234 slab_flags_t slab_flags;
1235 unsigned int useroffset; /* Usercopy region offset */
1236 unsigned int usersize; /* Usercopy region size */
1237
1238 struct percpu_counter *orphan_count;
1239
1240 struct request_sock_ops *rsk_prot;
1241 struct timewait_sock_ops *twsk_prot;
1242
1243 union {
1244 struct inet_hashinfo *hashinfo;
1245 struct udp_table *udp_table;
1246 struct raw_hashinfo *raw_hash;
1247 struct smc_hashinfo *smc_hash;
1248 } h;
1249
1250 struct module *owner;
1251
1252 char name[32];
1253
1254 struct list_head node;
1255#ifdef SOCK_REFCNT_DEBUG
1256 atomic_t socks;
1257#endif
1258 int (*diag_destroy)(struct sock *sk, int err);
1259} __randomize_layout;
1260
1261int proto_register(struct proto *prot, int alloc_slab);
1262void proto_unregister(struct proto *prot);
1263int sock_load_diag_module(int family, int protocol);
1264
1265#ifdef SOCK_REFCNT_DEBUG
1266static inline void sk_refcnt_debug_inc(struct sock *sk)
1267{
1268 atomic_inc(&sk->sk_prot->socks);
1269}
1270
1271static inline void sk_refcnt_debug_dec(struct sock *sk)
1272{
1273 atomic_dec(&sk->sk_prot->socks);
1274 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1275 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1276}
1277
1278static inline void sk_refcnt_debug_release(const struct sock *sk)
1279{
1280 if (refcount_read(&sk->sk_refcnt) != 1)
1281 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1282 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1283}
1284#else /* SOCK_REFCNT_DEBUG */
1285#define sk_refcnt_debug_inc(sk) do { } while (0)
1286#define sk_refcnt_debug_dec(sk) do { } while (0)
1287#define sk_refcnt_debug_release(sk) do { } while (0)
1288#endif /* SOCK_REFCNT_DEBUG */
1289
1290INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1291
1292static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1293{
1294 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1295 return false;
1296
1297#ifdef CONFIG_INET
1298 return sk->sk_prot->stream_memory_free ?
1299 INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1300 tcp_stream_memory_free,
1301 sk, wake) : true;
1302#else
1303 return sk->sk_prot->stream_memory_free ?
1304 sk->sk_prot->stream_memory_free(sk, wake) : true;
1305#endif
1306}
1307
1308static inline bool sk_stream_memory_free(const struct sock *sk)
1309{
1310 return __sk_stream_memory_free(sk, 0);
1311}
1312
1313static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1314{
1315 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1316 __sk_stream_memory_free(sk, wake);
1317}
1318
1319static inline bool sk_stream_is_writeable(const struct sock *sk)
1320{
1321 return __sk_stream_is_writeable(sk, 0);
1322}
1323
1324static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1325 struct cgroup *ancestor)
1326{
1327#ifdef CONFIG_SOCK_CGROUP_DATA
1328 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1329 ancestor);
1330#else
1331 return -ENOTSUPP;
1332#endif
1333}
1334
1335static inline bool sk_has_memory_pressure(const struct sock *sk)
1336{
1337 return sk->sk_prot->memory_pressure != NULL;
1338}
1339
1340static inline bool sk_under_memory_pressure(const struct sock *sk)
1341{
1342 if (!sk->sk_prot->memory_pressure)
1343 return false;
1344
1345 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1346 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1347 return true;
1348
1349 return !!*sk->sk_prot->memory_pressure;
1350}
1351
1352static inline long
1353sk_memory_allocated(const struct sock *sk)
1354{
1355 return atomic_long_read(sk->sk_prot->memory_allocated);
1356}
1357
1358static inline long
1359sk_memory_allocated_add(struct sock *sk, int amt)
1360{
1361 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1362}
1363
1364static inline void
1365sk_memory_allocated_sub(struct sock *sk, int amt)
1366{
1367 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1368}
1369
1370#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1371
1372static inline void sk_sockets_allocated_dec(struct sock *sk)
1373{
1374 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1375 SK_ALLOC_PERCPU_COUNTER_BATCH);
1376}
1377
1378static inline void sk_sockets_allocated_inc(struct sock *sk)
1379{
1380 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1381 SK_ALLOC_PERCPU_COUNTER_BATCH);
1382}
1383
1384static inline u64
1385sk_sockets_allocated_read_positive(struct sock *sk)
1386{
1387 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1388}
1389
1390static inline int
1391proto_sockets_allocated_sum_positive(struct proto *prot)
1392{
1393 return percpu_counter_sum_positive(prot->sockets_allocated);
1394}
1395
1396static inline long
1397proto_memory_allocated(struct proto *prot)
1398{
1399 return atomic_long_read(prot->memory_allocated);
1400}
1401
1402static inline bool
1403proto_memory_pressure(struct proto *prot)
1404{
1405 if (!prot->memory_pressure)
1406 return false;
1407 return !!*prot->memory_pressure;
1408}
1409
1410
1411#ifdef CONFIG_PROC_FS
1412/* Called with local bh disabled */
1413void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1414int sock_prot_inuse_get(struct net *net, struct proto *proto);
1415int sock_inuse_get(struct net *net);
1416#else
1417static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1418 int inc)
1419{
1420}
1421#endif
1422
1423
1424/* With per-bucket locks this operation is not-atomic, so that
1425 * this version is not worse.
1426 */
1427static inline int __sk_prot_rehash(struct sock *sk)
1428{
1429 sk->sk_prot->unhash(sk);
1430 return sk->sk_prot->hash(sk);
1431}
1432
1433/* About 10 seconds */
1434#define SOCK_DESTROY_TIME (10*HZ)
1435
1436/* Sockets 0-1023 can't be bound to unless you are superuser */
1437#define PROT_SOCK 1024
1438
1439#define SHUTDOWN_MASK 3
1440#define RCV_SHUTDOWN 1
1441#define SEND_SHUTDOWN 2
1442
1443#define SOCK_SNDBUF_LOCK 1
1444#define SOCK_RCVBUF_LOCK 2
1445#define SOCK_BINDADDR_LOCK 4
1446#define SOCK_BINDPORT_LOCK 8
1447
1448struct socket_alloc {
1449 struct socket socket;
1450 struct inode vfs_inode;
1451};
1452
1453static inline struct socket *SOCKET_I(struct inode *inode)
1454{
1455 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1456}
1457
1458static inline struct inode *SOCK_INODE(struct socket *socket)
1459{
1460 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1461}
1462
1463/*
1464 * Functions for memory accounting
1465 */
1466int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1467int __sk_mem_schedule(struct sock *sk, int size, int kind);
1468void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1469void __sk_mem_reclaim(struct sock *sk, int amount);
1470
1471/* We used to have PAGE_SIZE here, but systems with 64KB pages
1472 * do not necessarily have 16x time more memory than 4KB ones.
1473 */
1474#define SK_MEM_QUANTUM 4096
1475#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1476#define SK_MEM_SEND 0
1477#define SK_MEM_RECV 1
1478
1479/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1480static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1481{
1482 long val = sk->sk_prot->sysctl_mem[index];
1483
1484#if PAGE_SIZE > SK_MEM_QUANTUM
1485 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1486#elif PAGE_SIZE < SK_MEM_QUANTUM
1487 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1488#endif
1489 return val;
1490}
1491
1492static inline int sk_mem_pages(int amt)
1493{
1494 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1495}
1496
1497static inline bool sk_has_account(struct sock *sk)
1498{
1499 /* return true if protocol supports memory accounting */
1500 return !!sk->sk_prot->memory_allocated;
1501}
1502
1503static inline bool sk_wmem_schedule(struct sock *sk, int size)
1504{
1505 if (!sk_has_account(sk))
1506 return true;
1507 return size <= sk->sk_forward_alloc ||
1508 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1509}
1510
1511static inline bool
1512sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1513{
1514 if (!sk_has_account(sk))
1515 return true;
1516 return size <= sk->sk_forward_alloc ||
1517 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1518 skb_pfmemalloc(skb);
1519}
1520
1521static inline void sk_mem_reclaim(struct sock *sk)
1522{
1523 if (!sk_has_account(sk))
1524 return;
1525 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1526 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1527}
1528
1529static inline void sk_mem_reclaim_partial(struct sock *sk)
1530{
1531 if (!sk_has_account(sk))
1532 return;
1533 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1534 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1535}
1536
1537static inline void sk_mem_charge(struct sock *sk, int size)
1538{
1539 if (!sk_has_account(sk))
1540 return;
1541 sk->sk_forward_alloc -= size;
1542}
1543
1544static inline void sk_mem_uncharge(struct sock *sk, int size)
1545{
1546 if (!sk_has_account(sk))
1547 return;
1548 sk->sk_forward_alloc += size;
1549
1550 /* Avoid a possible overflow.
1551 * TCP send queues can make this happen, if sk_mem_reclaim()
1552 * is not called and more than 2 GBytes are released at once.
1553 *
1554 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1555 * no need to hold that much forward allocation anyway.
1556 */
1557 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1558 __sk_mem_reclaim(sk, 1 << 20);
1559}
1560
1561DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
1562static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1563{
1564 sk_wmem_queued_add(sk, -skb->truesize);
1565 sk_mem_uncharge(sk, skb->truesize);
1566 if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1567 !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1568 skb_ext_reset(skb);
1569 skb_zcopy_clear(skb, true);
1570 sk->sk_tx_skb_cache = skb;
1571 return;
1572 }
1573 __kfree_skb(skb);
1574}
1575
1576static inline void sock_release_ownership(struct sock *sk)
1577{
1578 if (sk->sk_lock.owned) {
1579 sk->sk_lock.owned = 0;
1580
1581 /* The sk_lock has mutex_unlock() semantics: */
1582 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1583 }
1584}
1585
1586/*
1587 * Macro so as to not evaluate some arguments when
1588 * lockdep is not enabled.
1589 *
1590 * Mark both the sk_lock and the sk_lock.slock as a
1591 * per-address-family lock class.
1592 */
1593#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1594do { \
1595 sk->sk_lock.owned = 0; \
1596 init_waitqueue_head(&sk->sk_lock.wq); \
1597 spin_lock_init(&(sk)->sk_lock.slock); \
1598 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1599 sizeof((sk)->sk_lock)); \
1600 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1601 (skey), (sname)); \
1602 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1603} while (0)
1604
1605static inline bool lockdep_sock_is_held(const struct sock *sk)
1606{
1607 return lockdep_is_held(&sk->sk_lock) ||
1608 lockdep_is_held(&sk->sk_lock.slock);
1609}
1610
1611void lock_sock_nested(struct sock *sk, int subclass);
1612
1613static inline void lock_sock(struct sock *sk)
1614{
1615 lock_sock_nested(sk, 0);
1616}
1617
1618void __lock_sock(struct sock *sk);
1619void __release_sock(struct sock *sk);
1620void release_sock(struct sock *sk);
1621
1622/* BH context may only use the following locking interface. */
1623#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1624#define bh_lock_sock_nested(__sk) \
1625 spin_lock_nested(&((__sk)->sk_lock.slock), \
1626 SINGLE_DEPTH_NESTING)
1627#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1628
1629bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1630
1631/**
1632 * unlock_sock_fast - complement of lock_sock_fast
1633 * @sk: socket
1634 * @slow: slow mode
1635 *
1636 * fast unlock socket for user context.
1637 * If slow mode is on, we call regular release_sock()
1638 */
1639static inline void unlock_sock_fast(struct sock *sk, bool slow)
1640 __releases(&sk->sk_lock.slock)
1641{
1642 if (slow) {
1643 release_sock(sk);
1644 __release(&sk->sk_lock.slock);
1645 } else {
1646 spin_unlock_bh(&sk->sk_lock.slock);
1647 }
1648}
1649
1650/* Used by processes to "lock" a socket state, so that
1651 * interrupts and bottom half handlers won't change it
1652 * from under us. It essentially blocks any incoming
1653 * packets, so that we won't get any new data or any
1654 * packets that change the state of the socket.
1655 *
1656 * While locked, BH processing will add new packets to
1657 * the backlog queue. This queue is processed by the
1658 * owner of the socket lock right before it is released.
1659 *
1660 * Since ~2.3.5 it is also exclusive sleep lock serializing
1661 * accesses from user process context.
1662 */
1663
1664static inline void sock_owned_by_me(const struct sock *sk)
1665{
1666#ifdef CONFIG_LOCKDEP
1667 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1668#endif
1669}
1670
1671static inline bool sock_owned_by_user(const struct sock *sk)
1672{
1673 sock_owned_by_me(sk);
1674 return sk->sk_lock.owned;
1675}
1676
1677static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1678{
1679 return sk->sk_lock.owned;
1680}
1681
1682/* no reclassification while locks are held */
1683static inline bool sock_allow_reclassification(const struct sock *csk)
1684{
1685 struct sock *sk = (struct sock *)csk;
1686
1687 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1688}
1689
1690struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1691 struct proto *prot, int kern);
1692void sk_free(struct sock *sk);
1693void sk_destruct(struct sock *sk);
1694struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1695void sk_free_unlock_clone(struct sock *sk);
1696
1697struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1698 gfp_t priority);
1699void __sock_wfree(struct sk_buff *skb);
1700void sock_wfree(struct sk_buff *skb);
1701struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1702 gfp_t priority);
1703void skb_orphan_partial(struct sk_buff *skb);
1704void sock_rfree(struct sk_buff *skb);
1705void sock_efree(struct sk_buff *skb);
1706#ifdef CONFIG_INET
1707void sock_edemux(struct sk_buff *skb);
1708void sock_pfree(struct sk_buff *skb);
1709#else
1710#define sock_edemux sock_efree
1711#endif
1712
1713int sock_setsockopt(struct socket *sock, int level, int op,
1714 sockptr_t optval, unsigned int optlen);
1715
1716int sock_getsockopt(struct socket *sock, int level, int op,
1717 char __user *optval, int __user *optlen);
1718int sock_gettstamp(struct socket *sock, void __user *userstamp,
1719 bool timeval, bool time32);
1720struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1721 int noblock, int *errcode);
1722struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1723 unsigned long data_len, int noblock,
1724 int *errcode, int max_page_order);
1725void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1726void sock_kfree_s(struct sock *sk, void *mem, int size);
1727void sock_kzfree_s(struct sock *sk, void *mem, int size);
1728void sk_send_sigurg(struct sock *sk);
1729
1730struct sockcm_cookie {
1731 u64 transmit_time;
1732 u32 mark;
1733 u16 tsflags;
1734};
1735
1736static inline void sockcm_init(struct sockcm_cookie *sockc,
1737 const struct sock *sk)
1738{
1739 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1740}
1741
1742int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1743 struct sockcm_cookie *sockc);
1744int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1745 struct sockcm_cookie *sockc);
1746
1747/*
1748 * Functions to fill in entries in struct proto_ops when a protocol
1749 * does not implement a particular function.
1750 */
1751int sock_no_bind(struct socket *, struct sockaddr *, int);
1752int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1753int sock_no_socketpair(struct socket *, struct socket *);
1754int sock_no_accept(struct socket *, struct socket *, int, bool);
1755int sock_no_getname(struct socket *, struct sockaddr *, int);
1756int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1757int sock_no_listen(struct socket *, int);
1758int sock_no_shutdown(struct socket *, int);
1759int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1760int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1761int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1762int sock_no_mmap(struct file *file, struct socket *sock,
1763 struct vm_area_struct *vma);
1764ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1765 size_t size, int flags);
1766ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1767 int offset, size_t size, int flags);
1768
1769/*
1770 * Functions to fill in entries in struct proto_ops when a protocol
1771 * uses the inet style.
1772 */
1773int sock_common_getsockopt(struct socket *sock, int level, int optname,
1774 char __user *optval, int __user *optlen);
1775int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1776 int flags);
1777int sock_common_setsockopt(struct socket *sock, int level, int optname,
1778 sockptr_t optval, unsigned int optlen);
1779
1780void sk_common_release(struct sock *sk);
1781
1782/*
1783 * Default socket callbacks and setup code
1784 */
1785
1786/* Initialise core socket variables */
1787void sock_init_data(struct socket *sock, struct sock *sk);
1788
1789/*
1790 * Socket reference counting postulates.
1791 *
1792 * * Each user of socket SHOULD hold a reference count.
1793 * * Each access point to socket (an hash table bucket, reference from a list,
1794 * running timer, skb in flight MUST hold a reference count.
1795 * * When reference count hits 0, it means it will never increase back.
1796 * * When reference count hits 0, it means that no references from
1797 * outside exist to this socket and current process on current CPU
1798 * is last user and may/should destroy this socket.
1799 * * sk_free is called from any context: process, BH, IRQ. When
1800 * it is called, socket has no references from outside -> sk_free
1801 * may release descendant resources allocated by the socket, but
1802 * to the time when it is called, socket is NOT referenced by any
1803 * hash tables, lists etc.
1804 * * Packets, delivered from outside (from network or from another process)
1805 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1806 * when they sit in queue. Otherwise, packets will leak to hole, when
1807 * socket is looked up by one cpu and unhasing is made by another CPU.
1808 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1809 * (leak to backlog). Packet socket does all the processing inside
1810 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1811 * use separate SMP lock, so that they are prone too.
1812 */
1813
1814/* Ungrab socket and destroy it, if it was the last reference. */
1815static inline void sock_put(struct sock *sk)
1816{
1817 if (refcount_dec_and_test(&sk->sk_refcnt))
1818 sk_free(sk);
1819}
1820/* Generic version of sock_put(), dealing with all sockets
1821 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1822 */
1823void sock_gen_put(struct sock *sk);
1824
1825int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1826 unsigned int trim_cap, bool refcounted);
1827static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1828 const int nested)
1829{
1830 return __sk_receive_skb(sk, skb, nested, 1, true);
1831}
1832
1833static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1834{
1835 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1836 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1837 return;
1838 sk->sk_tx_queue_mapping = tx_queue;
1839}
1840
1841#define NO_QUEUE_MAPPING USHRT_MAX
1842
1843static inline void sk_tx_queue_clear(struct sock *sk)
1844{
1845 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1846}
1847
1848static inline int sk_tx_queue_get(const struct sock *sk)
1849{
1850 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1851 return sk->sk_tx_queue_mapping;
1852
1853 return -1;
1854}
1855
1856static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1857{
1858#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1859 if (skb_rx_queue_recorded(skb)) {
1860 u16 rx_queue = skb_get_rx_queue(skb);
1861
1862 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1863 return;
1864
1865 sk->sk_rx_queue_mapping = rx_queue;
1866 }
1867#endif
1868}
1869
1870static inline void sk_rx_queue_clear(struct sock *sk)
1871{
1872#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1873 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1874#endif
1875}
1876
1877static inline int sk_rx_queue_get(const struct sock *sk)
1878{
1879#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1880 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1881 return sk->sk_rx_queue_mapping;
1882#endif
1883
1884 return -1;
1885}
1886
1887static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1888{
1889 sk->sk_socket = sock;
1890}
1891
1892static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1893{
1894 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1895 return &rcu_dereference_raw(sk->sk_wq)->wait;
1896}
1897/* Detach socket from process context.
1898 * Announce socket dead, detach it from wait queue and inode.
1899 * Note that parent inode held reference count on this struct sock,
1900 * we do not release it in this function, because protocol
1901 * probably wants some additional cleanups or even continuing
1902 * to work with this socket (TCP).
1903 */
1904static inline void sock_orphan(struct sock *sk)
1905{
1906 write_lock_bh(&sk->sk_callback_lock);
1907 sock_set_flag(sk, SOCK_DEAD);
1908 sk_set_socket(sk, NULL);
1909 sk->sk_wq = NULL;
1910 write_unlock_bh(&sk->sk_callback_lock);
1911}
1912
1913static inline void sock_graft(struct sock *sk, struct socket *parent)
1914{
1915 WARN_ON(parent->sk);
1916 write_lock_bh(&sk->sk_callback_lock);
1917 rcu_assign_pointer(sk->sk_wq, &parent->wq);
1918 parent->sk = sk;
1919 sk_set_socket(sk, parent);
1920 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1921 security_sock_graft(sk, parent);
1922 write_unlock_bh(&sk->sk_callback_lock);
1923}
1924
1925kuid_t sock_i_uid(struct sock *sk);
1926unsigned long sock_i_ino(struct sock *sk);
1927
1928static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1929{
1930 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1931}
1932
1933static inline u32 net_tx_rndhash(void)
1934{
1935 u32 v = prandom_u32();
1936
1937 return v ?: 1;
1938}
1939
1940static inline void sk_set_txhash(struct sock *sk)
1941{
1942 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
1943 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
1944}
1945
1946static inline bool sk_rethink_txhash(struct sock *sk)
1947{
1948 if (sk->sk_txhash) {
1949 sk_set_txhash(sk);
1950 return true;
1951 }
1952 return false;
1953}
1954
1955static inline struct dst_entry *
1956__sk_dst_get(struct sock *sk)
1957{
1958 return rcu_dereference_check(sk->sk_dst_cache,
1959 lockdep_sock_is_held(sk));
1960}
1961
1962static inline struct dst_entry *
1963sk_dst_get(struct sock *sk)
1964{
1965 struct dst_entry *dst;
1966
1967 rcu_read_lock();
1968 dst = rcu_dereference(sk->sk_dst_cache);
1969 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1970 dst = NULL;
1971 rcu_read_unlock();
1972 return dst;
1973}
1974
1975static inline void __dst_negative_advice(struct sock *sk)
1976{
1977 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1978
1979 if (dst && dst->ops->negative_advice) {
1980 ndst = dst->ops->negative_advice(dst);
1981
1982 if (ndst != dst) {
1983 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1984 sk_tx_queue_clear(sk);
1985 sk->sk_dst_pending_confirm = 0;
1986 }
1987 }
1988}
1989
1990static inline void dst_negative_advice(struct sock *sk)
1991{
1992 sk_rethink_txhash(sk);
1993 __dst_negative_advice(sk);
1994}
1995
1996static inline void
1997__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1998{
1999 struct dst_entry *old_dst;
2000
2001 sk_tx_queue_clear(sk);
2002 sk->sk_dst_pending_confirm = 0;
2003 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2004 lockdep_sock_is_held(sk));
2005 rcu_assign_pointer(sk->sk_dst_cache, dst);
2006 dst_release(old_dst);
2007}
2008
2009static inline void
2010sk_dst_set(struct sock *sk, struct dst_entry *dst)
2011{
2012 struct dst_entry *old_dst;
2013
2014 sk_tx_queue_clear(sk);
2015 sk->sk_dst_pending_confirm = 0;
2016 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2017 dst_release(old_dst);
2018}
2019
2020static inline void
2021__sk_dst_reset(struct sock *sk)
2022{
2023 __sk_dst_set(sk, NULL);
2024}
2025
2026static inline void
2027sk_dst_reset(struct sock *sk)
2028{
2029 sk_dst_set(sk, NULL);
2030}
2031
2032struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2033
2034struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2035
2036static inline void sk_dst_confirm(struct sock *sk)
2037{
2038 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2039 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2040}
2041
2042static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2043{
2044 if (skb_get_dst_pending_confirm(skb)) {
2045 struct sock *sk = skb->sk;
2046 unsigned long now = jiffies;
2047
2048 /* avoid dirtying neighbour */
2049 if (READ_ONCE(n->confirmed) != now)
2050 WRITE_ONCE(n->confirmed, now);
2051 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2052 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2053 }
2054}
2055
2056bool sk_mc_loop(struct sock *sk);
2057
2058static inline bool sk_can_gso(const struct sock *sk)
2059{
2060 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2061}
2062
2063void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2064
2065static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2066{
2067 sk->sk_route_nocaps |= flags;
2068 sk->sk_route_caps &= ~flags;
2069}
2070
2071static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2072 struct iov_iter *from, char *to,
2073 int copy, int offset)
2074{
2075 if (skb->ip_summed == CHECKSUM_NONE) {
2076 __wsum csum = 0;
2077 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2078 return -EFAULT;
2079 skb->csum = csum_block_add(skb->csum, csum, offset);
2080 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2081 if (!copy_from_iter_full_nocache(to, copy, from))
2082 return -EFAULT;
2083 } else if (!copy_from_iter_full(to, copy, from))
2084 return -EFAULT;
2085
2086 return 0;
2087}
2088
2089static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2090 struct iov_iter *from, int copy)
2091{
2092 int err, offset = skb->len;
2093
2094 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2095 copy, offset);
2096 if (err)
2097 __skb_trim(skb, offset);
2098
2099 return err;
2100}
2101
2102static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2103 struct sk_buff *skb,
2104 struct page *page,
2105 int off, int copy)
2106{
2107 int err;
2108
2109 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2110 copy, skb->len);
2111 if (err)
2112 return err;
2113
2114 skb->len += copy;
2115 skb->data_len += copy;
2116 skb->truesize += copy;
2117 sk_wmem_queued_add(sk, copy);
2118 sk_mem_charge(sk, copy);
2119 return 0;
2120}
2121
2122/**
2123 * sk_wmem_alloc_get - returns write allocations
2124 * @sk: socket
2125 *
2126 * Return: sk_wmem_alloc minus initial offset of one
2127 */
2128static inline int sk_wmem_alloc_get(const struct sock *sk)
2129{
2130 return refcount_read(&sk->sk_wmem_alloc) - 1;
2131}
2132
2133/**
2134 * sk_rmem_alloc_get - returns read allocations
2135 * @sk: socket
2136 *
2137 * Return: sk_rmem_alloc
2138 */
2139static inline int sk_rmem_alloc_get(const struct sock *sk)
2140{
2141 return atomic_read(&sk->sk_rmem_alloc);
2142}
2143
2144/**
2145 * sk_has_allocations - check if allocations are outstanding
2146 * @sk: socket
2147 *
2148 * Return: true if socket has write or read allocations
2149 */
2150static inline bool sk_has_allocations(const struct sock *sk)
2151{
2152 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2153}
2154
2155/**
2156 * skwq_has_sleeper - check if there are any waiting processes
2157 * @wq: struct socket_wq
2158 *
2159 * Return: true if socket_wq has waiting processes
2160 *
2161 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2162 * barrier call. They were added due to the race found within the tcp code.
2163 *
2164 * Consider following tcp code paths::
2165 *
2166 * CPU1 CPU2
2167 * sys_select receive packet
2168 * ... ...
2169 * __add_wait_queue update tp->rcv_nxt
2170 * ... ...
2171 * tp->rcv_nxt check sock_def_readable
2172 * ... {
2173 * schedule rcu_read_lock();
2174 * wq = rcu_dereference(sk->sk_wq);
2175 * if (wq && waitqueue_active(&wq->wait))
2176 * wake_up_interruptible(&wq->wait)
2177 * ...
2178 * }
2179 *
2180 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2181 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2182 * could then endup calling schedule and sleep forever if there are no more
2183 * data on the socket.
2184 *
2185 */
2186static inline bool skwq_has_sleeper(struct socket_wq *wq)
2187{
2188 return wq && wq_has_sleeper(&wq->wait);
2189}
2190
2191/**
2192 * sock_poll_wait - place memory barrier behind the poll_wait call.
2193 * @filp: file
2194 * @sock: socket to wait on
2195 * @p: poll_table
2196 *
2197 * See the comments in the wq_has_sleeper function.
2198 */
2199static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2200 poll_table *p)
2201{
2202 if (!poll_does_not_wait(p)) {
2203 poll_wait(filp, &sock->wq.wait, p);
2204 /* We need to be sure we are in sync with the
2205 * socket flags modification.
2206 *
2207 * This memory barrier is paired in the wq_has_sleeper.
2208 */
2209 smp_mb();
2210 }
2211}
2212
2213static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2214{
2215 /* This pairs with WRITE_ONCE() in sk_set_txhash() */
2216 u32 txhash = READ_ONCE(sk->sk_txhash);
2217
2218 if (txhash) {
2219 skb->l4_hash = 1;
2220 skb->hash = txhash;
2221 }
2222}
2223
2224void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2225
2226/*
2227 * Queue a received datagram if it will fit. Stream and sequenced
2228 * protocols can't normally use this as they need to fit buffers in
2229 * and play with them.
2230 *
2231 * Inlined as it's very short and called for pretty much every
2232 * packet ever received.
2233 */
2234static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2235{
2236 skb_orphan(skb);
2237 skb->sk = sk;
2238 skb->destructor = sock_rfree;
2239 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2240 sk_mem_charge(sk, skb->truesize);
2241}
2242
2243static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2244{
2245 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2246 skb_orphan(skb);
2247 skb->destructor = sock_efree;
2248 skb->sk = sk;
2249 return true;
2250 }
2251 return false;
2252}
2253
2254void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2255 unsigned long expires);
2256
2257void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2258
2259void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2260
2261int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2262 struct sk_buff *skb, unsigned int flags,
2263 void (*destructor)(struct sock *sk,
2264 struct sk_buff *skb));
2265int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2266int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2267
2268int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2269struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2270
2271/*
2272 * Recover an error report and clear atomically
2273 */
2274
2275static inline int sock_error(struct sock *sk)
2276{
2277 int err;
2278
2279 /* Avoid an atomic operation for the common case.
2280 * This is racy since another cpu/thread can change sk_err under us.
2281 */
2282 if (likely(data_race(!sk->sk_err)))
2283 return 0;
2284
2285 err = xchg(&sk->sk_err, 0);
2286 return -err;
2287}
2288
2289void sk_error_report(struct sock *sk);
2290
2291static inline unsigned long sock_wspace(struct sock *sk)
2292{
2293 int amt = 0;
2294
2295 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2296 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2297 if (amt < 0)
2298 amt = 0;
2299 }
2300 return amt;
2301}
2302
2303/* Note:
2304 * We use sk->sk_wq_raw, from contexts knowing this
2305 * pointer is not NULL and cannot disappear/change.
2306 */
2307static inline void sk_set_bit(int nr, struct sock *sk)
2308{
2309 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2310 !sock_flag(sk, SOCK_FASYNC))
2311 return;
2312
2313 set_bit(nr, &sk->sk_wq_raw->flags);
2314}
2315
2316static inline void sk_clear_bit(int nr, struct sock *sk)
2317{
2318 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2319 !sock_flag(sk, SOCK_FASYNC))
2320 return;
2321
2322 clear_bit(nr, &sk->sk_wq_raw->flags);
2323}
2324
2325static inline void sk_wake_async(const struct sock *sk, int how, int band)
2326{
2327 if (sock_flag(sk, SOCK_FASYNC)) {
2328 rcu_read_lock();
2329 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2330 rcu_read_unlock();
2331 }
2332}
2333
2334/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2335 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2336 * Note: for send buffers, TCP works better if we can build two skbs at
2337 * minimum.
2338 */
2339#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2340
2341#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2342#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2343
2344static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2345{
2346 u32 val;
2347
2348 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2349 return;
2350
2351 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2352
2353 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2354}
2355
2356struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2357 bool force_schedule);
2358
2359/**
2360 * sk_page_frag - return an appropriate page_frag
2361 * @sk: socket
2362 *
2363 * Use the per task page_frag instead of the per socket one for
2364 * optimization when we know that we're in the normal context and owns
2365 * everything that's associated with %current.
2366 *
2367 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2368 * inside other socket operations and end up recursing into sk_page_frag()
2369 * while it's already in use.
2370 *
2371 * Return: a per task page_frag if context allows that,
2372 * otherwise a per socket one.
2373 */
2374static inline struct page_frag *sk_page_frag(struct sock *sk)
2375{
2376 if (gfpflags_normal_context(sk->sk_allocation))
2377 return ¤t->task_frag;
2378
2379 return &sk->sk_frag;
2380}
2381
2382bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2383
2384/*
2385 * Default write policy as shown to user space via poll/select/SIGIO
2386 */
2387static inline bool sock_writeable(const struct sock *sk)
2388{
2389 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2390}
2391
2392static inline gfp_t gfp_any(void)
2393{
2394 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2395}
2396
2397static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2398{
2399 return noblock ? 0 : sk->sk_rcvtimeo;
2400}
2401
2402static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2403{
2404 return noblock ? 0 : sk->sk_sndtimeo;
2405}
2406
2407static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2408{
2409 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2410
2411 return v ?: 1;
2412}
2413
2414/* Alas, with timeout socket operations are not restartable.
2415 * Compare this to poll().
2416 */
2417static inline int sock_intr_errno(long timeo)
2418{
2419 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2420}
2421
2422struct sock_skb_cb {
2423 u32 dropcount;
2424};
2425
2426/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2427 * using skb->cb[] would keep using it directly and utilize its
2428 * alignement guarantee.
2429 */
2430#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2431 sizeof(struct sock_skb_cb)))
2432
2433#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2434 SOCK_SKB_CB_OFFSET))
2435
2436#define sock_skb_cb_check_size(size) \
2437 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2438
2439static inline void
2440sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2441{
2442 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2443 atomic_read(&sk->sk_drops) : 0;
2444}
2445
2446static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2447{
2448 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2449
2450 atomic_add(segs, &sk->sk_drops);
2451}
2452
2453static inline ktime_t sock_read_timestamp(struct sock *sk)
2454{
2455#if BITS_PER_LONG==32
2456 unsigned int seq;
2457 ktime_t kt;
2458
2459 do {
2460 seq = read_seqbegin(&sk->sk_stamp_seq);
2461 kt = sk->sk_stamp;
2462 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2463
2464 return kt;
2465#else
2466 return READ_ONCE(sk->sk_stamp);
2467#endif
2468}
2469
2470static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2471{
2472#if BITS_PER_LONG==32
2473 write_seqlock(&sk->sk_stamp_seq);
2474 sk->sk_stamp = kt;
2475 write_sequnlock(&sk->sk_stamp_seq);
2476#else
2477 WRITE_ONCE(sk->sk_stamp, kt);
2478#endif
2479}
2480
2481void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2482 struct sk_buff *skb);
2483void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2484 struct sk_buff *skb);
2485
2486static inline void
2487sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2488{
2489 ktime_t kt = skb->tstamp;
2490 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2491
2492 /*
2493 * generate control messages if
2494 * - receive time stamping in software requested
2495 * - software time stamp available and wanted
2496 * - hardware time stamps available and wanted
2497 */
2498 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2499 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2500 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2501 (hwtstamps->hwtstamp &&
2502 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2503 __sock_recv_timestamp(msg, sk, skb);
2504 else
2505 sock_write_timestamp(sk, kt);
2506
2507 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2508 __sock_recv_wifi_status(msg, sk, skb);
2509}
2510
2511void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2512 struct sk_buff *skb);
2513
2514#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2515static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2516 struct sk_buff *skb)
2517{
2518#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2519 (1UL << SOCK_RCVTSTAMP))
2520#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2521 SOF_TIMESTAMPING_RAW_HARDWARE)
2522
2523 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2524 __sock_recv_ts_and_drops(msg, sk, skb);
2525 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2526 sock_write_timestamp(sk, skb->tstamp);
2527 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2528 sock_write_timestamp(sk, 0);
2529}
2530
2531void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2532
2533/**
2534 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2535 * @sk: socket sending this packet
2536 * @tsflags: timestamping flags to use
2537 * @tx_flags: completed with instructions for time stamping
2538 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2539 *
2540 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2541 */
2542static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2543 __u8 *tx_flags, __u32 *tskey)
2544{
2545 if (unlikely(tsflags)) {
2546 __sock_tx_timestamp(tsflags, tx_flags);
2547 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2548 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2549 *tskey = sk->sk_tskey++;
2550 }
2551 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2552 *tx_flags |= SKBTX_WIFI_STATUS;
2553}
2554
2555static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2556 __u8 *tx_flags)
2557{
2558 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2559}
2560
2561static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2562{
2563 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2564 &skb_shinfo(skb)->tskey);
2565}
2566
2567DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2568/**
2569 * sk_eat_skb - Release a skb if it is no longer needed
2570 * @sk: socket to eat this skb from
2571 * @skb: socket buffer to eat
2572 *
2573 * This routine must be called with interrupts disabled or with the socket
2574 * locked so that the sk_buff queue operation is ok.
2575*/
2576static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2577{
2578 __skb_unlink(skb, &sk->sk_receive_queue);
2579 if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2580 !sk->sk_rx_skb_cache) {
2581 sk->sk_rx_skb_cache = skb;
2582 skb_orphan(skb);
2583 return;
2584 }
2585 __kfree_skb(skb);
2586}
2587
2588static inline
2589struct net *sock_net(const struct sock *sk)
2590{
2591 return read_pnet(&sk->sk_net);
2592}
2593
2594static inline
2595void sock_net_set(struct sock *sk, struct net *net)
2596{
2597 write_pnet(&sk->sk_net, net);
2598}
2599
2600static inline bool
2601skb_sk_is_prefetched(struct sk_buff *skb)
2602{
2603#ifdef CONFIG_INET
2604 return skb->destructor == sock_pfree;
2605#else
2606 return false;
2607#endif /* CONFIG_INET */
2608}
2609
2610/* This helper checks if a socket is a full socket,
2611 * ie _not_ a timewait or request socket.
2612 */
2613static inline bool sk_fullsock(const struct sock *sk)
2614{
2615 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2616}
2617
2618static inline bool
2619sk_is_refcounted(struct sock *sk)
2620{
2621 /* Only full sockets have sk->sk_flags. */
2622 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2623}
2624
2625/**
2626 * skb_steal_sock - steal a socket from an sk_buff
2627 * @skb: sk_buff to steal the socket from
2628 * @refcounted: is set to true if the socket is reference-counted
2629 */
2630static inline struct sock *
2631skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2632{
2633 if (skb->sk) {
2634 struct sock *sk = skb->sk;
2635
2636 *refcounted = true;
2637 if (skb_sk_is_prefetched(skb))
2638 *refcounted = sk_is_refcounted(sk);
2639 skb->destructor = NULL;
2640 skb->sk = NULL;
2641 return sk;
2642 }
2643 *refcounted = false;
2644 return NULL;
2645}
2646
2647/* Checks if this SKB belongs to an HW offloaded socket
2648 * and whether any SW fallbacks are required based on dev.
2649 * Check decrypted mark in case skb_orphan() cleared socket.
2650 */
2651static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2652 struct net_device *dev)
2653{
2654#ifdef CONFIG_SOCK_VALIDATE_XMIT
2655 struct sock *sk = skb->sk;
2656
2657 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2658 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2659#ifdef CONFIG_TLS_DEVICE
2660 } else if (unlikely(skb->decrypted)) {
2661 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2662 kfree_skb(skb);
2663 skb = NULL;
2664#endif
2665 }
2666#endif
2667
2668 return skb;
2669}
2670
2671/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2672 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2673 */
2674static inline bool sk_listener(const struct sock *sk)
2675{
2676 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2677}
2678
2679void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2680int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2681 int type);
2682
2683bool sk_ns_capable(const struct sock *sk,
2684 struct user_namespace *user_ns, int cap);
2685bool sk_capable(const struct sock *sk, int cap);
2686bool sk_net_capable(const struct sock *sk, int cap);
2687
2688void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2689
2690/* Take into consideration the size of the struct sk_buff overhead in the
2691 * determination of these values, since that is non-constant across
2692 * platforms. This makes socket queueing behavior and performance
2693 * not depend upon such differences.
2694 */
2695#define _SK_MEM_PACKETS 256
2696#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2697#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2698#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2699
2700extern __u32 sysctl_wmem_max;
2701extern __u32 sysctl_rmem_max;
2702
2703extern int sysctl_tstamp_allow_data;
2704extern int sysctl_optmem_max;
2705
2706extern __u32 sysctl_wmem_default;
2707extern __u32 sysctl_rmem_default;
2708
2709DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2710
2711static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2712{
2713 /* Does this proto have per netns sysctl_wmem ? */
2714 if (proto->sysctl_wmem_offset)
2715 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2716
2717 return *proto->sysctl_wmem;
2718}
2719
2720static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2721{
2722 /* Does this proto have per netns sysctl_rmem ? */
2723 if (proto->sysctl_rmem_offset)
2724 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2725
2726 return *proto->sysctl_rmem;
2727}
2728
2729/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2730 * Some wifi drivers need to tweak it to get more chunks.
2731 * They can use this helper from their ndo_start_xmit()
2732 */
2733static inline void sk_pacing_shift_update(struct sock *sk, int val)
2734{
2735 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2736 return;
2737 WRITE_ONCE(sk->sk_pacing_shift, val);
2738}
2739
2740/* if a socket is bound to a device, check that the given device
2741 * index is either the same or that the socket is bound to an L3
2742 * master device and the given device index is also enslaved to
2743 * that L3 master
2744 */
2745static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2746{
2747 int mdif;
2748
2749 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2750 return true;
2751
2752 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2753 if (mdif && mdif == sk->sk_bound_dev_if)
2754 return true;
2755
2756 return false;
2757}
2758
2759void sock_def_readable(struct sock *sk);
2760
2761int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2762void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2763int sock_set_timestamping(struct sock *sk, int optname,
2764 struct so_timestamping timestamping);
2765
2766void sock_enable_timestamps(struct sock *sk);
2767void sock_no_linger(struct sock *sk);
2768void sock_set_keepalive(struct sock *sk);
2769void sock_set_priority(struct sock *sk, u32 priority);
2770void sock_set_rcvbuf(struct sock *sk, int val);
2771void sock_set_mark(struct sock *sk, u32 val);
2772void sock_set_reuseaddr(struct sock *sk);
2773void sock_set_reuseport(struct sock *sk);
2774void sock_set_sndtimeo(struct sock *sk, s64 secs);
2775
2776int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2777
2778#endif /* _SOCK_H */