xref: /linux/include/net/sock.h (revision 27605c8c0f69e319df156b471974e4e223035378)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Definitions for the AF_INET socket handler.
8  *
9  * Version:	@(#)sock.h	1.0.4	05/13/93
10  *
11  * Authors:	Ross Biro
12  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13  *		Corey Minyard <wf-rch!minyard@relay.EU.net>
14  *		Florian La Roche <flla@stud.uni-sb.de>
15  *
16  * Fixes:
17  *		Alan Cox	:	Volatiles in skbuff pointers. See
18  *					skbuff comments. May be overdone,
19  *					better to prove they can be removed
20  *					than the reverse.
21  *		Alan Cox	:	Added a zapped field for tcp to note
22  *					a socket is reset and must stay shut up
23  *		Alan Cox	:	New fields for options
24  *	Pauline Middelink	:	identd support
25  *		Alan Cox	:	Eliminate low level recv/recvfrom
26  *		David S. Miller	:	New socket lookup architecture.
27  *              Steve Whitehouse:       Default routines for sock_ops
28  *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
29  *              			protinfo be just a void pointer, as the
30  *              			protocol specific parts were moved to
31  *              			respective headers and ipv4/v6, etc now
32  *              			use private slabcaches for its socks
33  *              Pedro Hortas	:	New flags field for socket options
34  */
35 #ifndef _SOCK_H
36 #define _SOCK_H
37 
38 #include <linux/hardirq.h>
39 #include <linux/kernel.h>
40 #include <linux/list.h>
41 #include <linux/list_nulls.h>
42 #include <linux/timer.h>
43 #include <linux/cache.h>
44 #include <linux/bitops.h>
45 #include <linux/lockdep.h>
46 #include <linux/netdevice.h>
47 #include <linux/skbuff.h>	/* struct sk_buff */
48 #include <linux/mm.h>
49 #include <linux/security.h>
50 #include <linux/slab.h>
51 #include <linux/uaccess.h>
52 #include <linux/page_counter.h>
53 #include <linux/memcontrol.h>
54 #include <linux/static_key.h>
55 #include <linux/sched.h>
56 #include <linux/wait.h>
57 #include <linux/cgroup-defs.h>
58 #include <linux/rbtree.h>
59 #include <linux/rculist_nulls.h>
60 #include <linux/poll.h>
61 #include <linux/sockptr.h>
62 #include <linux/indirect_call_wrapper.h>
63 #include <linux/atomic.h>
64 #include <linux/refcount.h>
65 #include <linux/llist.h>
66 #include <net/dst.h>
67 #include <net/checksum.h>
68 #include <net/tcp_states.h>
69 #include <linux/net_tstamp.h>
70 #include <net/l3mdev.h>
71 #include <uapi/linux/socket.h>
72 
73 /*
74  * This structure really needs to be cleaned up.
75  * Most of it is for TCP, and not used by any of
76  * the other protocols.
77  */
78 
79 /* This is the per-socket lock.  The spinlock provides a synchronization
80  * between user contexts and software interrupt processing, whereas the
81  * mini-semaphore synchronizes multiple users amongst themselves.
82  */
83 typedef struct {
84 	spinlock_t		slock;
85 	int			owned;
86 	wait_queue_head_t	wq;
87 	/*
88 	 * We express the mutex-alike socket_lock semantics
89 	 * to the lock validator by explicitly managing
90 	 * the slock as a lock variant (in addition to
91 	 * the slock itself):
92 	 */
93 #ifdef CONFIG_DEBUG_LOCK_ALLOC
94 	struct lockdep_map dep_map;
95 #endif
96 } socket_lock_t;
97 
98 struct sock;
99 struct proto;
100 struct net;
101 
102 typedef __u32 __bitwise __portpair;
103 typedef __u64 __bitwise __addrpair;
104 
105 /**
106  *	struct sock_common - minimal network layer representation of sockets
107  *	@skc_daddr: Foreign IPv4 addr
108  *	@skc_rcv_saddr: Bound local IPv4 addr
109  *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
110  *	@skc_hash: hash value used with various protocol lookup tables
111  *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
112  *	@skc_dport: placeholder for inet_dport/tw_dport
113  *	@skc_num: placeholder for inet_num/tw_num
114  *	@skc_portpair: __u32 union of @skc_dport & @skc_num
115  *	@skc_family: network address family
116  *	@skc_state: Connection state
117  *	@skc_reuse: %SO_REUSEADDR setting
118  *	@skc_reuseport: %SO_REUSEPORT setting
119  *	@skc_ipv6only: socket is IPV6 only
120  *	@skc_net_refcnt: socket is using net ref counting
121  *	@skc_bound_dev_if: bound device index if != 0
122  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
123  *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
124  *	@skc_prot: protocol handlers inside a network family
125  *	@skc_net: reference to the network namespace of this socket
126  *	@skc_v6_daddr: IPV6 destination address
127  *	@skc_v6_rcv_saddr: IPV6 source address
128  *	@skc_cookie: socket's cookie value
129  *	@skc_node: main hash linkage for various protocol lookup tables
130  *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
131  *	@skc_tx_queue_mapping: tx queue number for this connection
132  *	@skc_rx_queue_mapping: rx queue number for this connection
133  *	@skc_flags: place holder for sk_flags
134  *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
135  *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
136  *	@skc_listener: connection request listener socket (aka rsk_listener)
137  *		[union with @skc_flags]
138  *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
139  *		[union with @skc_flags]
140  *	@skc_incoming_cpu: record/match cpu processing incoming packets
141  *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
142  *		[union with @skc_incoming_cpu]
143  *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
144  *		[union with @skc_incoming_cpu]
145  *	@skc_refcnt: reference count
146  *
147  *	This is the minimal network layer representation of sockets, the header
148  *	for struct sock and struct inet_timewait_sock.
149  */
150 struct sock_common {
151 	union {
152 		__addrpair	skc_addrpair;
153 		struct {
154 			__be32	skc_daddr;
155 			__be32	skc_rcv_saddr;
156 		};
157 	};
158 	union  {
159 		unsigned int	skc_hash;
160 		__u16		skc_u16hashes[2];
161 	};
162 	/* skc_dport && skc_num must be grouped as well */
163 	union {
164 		__portpair	skc_portpair;
165 		struct {
166 			__be16	skc_dport;
167 			__u16	skc_num;
168 		};
169 	};
170 
171 	unsigned short		skc_family;
172 	volatile unsigned char	skc_state;
173 	unsigned char		skc_reuse:4;
174 	unsigned char		skc_reuseport:1;
175 	unsigned char		skc_ipv6only:1;
176 	unsigned char		skc_net_refcnt:1;
177 	int			skc_bound_dev_if;
178 	union {
179 		struct hlist_node	skc_bind_node;
180 		struct hlist_node	skc_portaddr_node;
181 	};
182 	struct proto		*skc_prot;
183 	possible_net_t		skc_net;
184 
185 #if IS_ENABLED(CONFIG_IPV6)
186 	struct in6_addr		skc_v6_daddr;
187 	struct in6_addr		skc_v6_rcv_saddr;
188 #endif
189 
190 	atomic64_t		skc_cookie;
191 
192 	/* following fields are padding to force
193 	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
194 	 * assuming IPV6 is enabled. We use this padding differently
195 	 * for different kind of 'sockets'
196 	 */
197 	union {
198 		unsigned long	skc_flags;
199 		struct sock	*skc_listener; /* request_sock */
200 		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
201 	};
202 	/*
203 	 * fields between dontcopy_begin/dontcopy_end
204 	 * are not copied in sock_copy()
205 	 */
206 	/* private: */
207 	int			skc_dontcopy_begin[0];
208 	/* public: */
209 	union {
210 		struct hlist_node	skc_node;
211 		struct hlist_nulls_node skc_nulls_node;
212 	};
213 	unsigned short		skc_tx_queue_mapping;
214 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
215 	unsigned short		skc_rx_queue_mapping;
216 #endif
217 	union {
218 		int		skc_incoming_cpu;
219 		u32		skc_rcv_wnd;
220 		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
221 	};
222 
223 	refcount_t		skc_refcnt;
224 	/* private: */
225 	int                     skc_dontcopy_end[0];
226 	union {
227 		u32		skc_rxhash;
228 		u32		skc_window_clamp;
229 		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
230 	};
231 	/* public: */
232 };
233 
234 struct bpf_local_storage;
235 struct sk_filter;
236 
237 /**
238   *	struct sock - network layer representation of sockets
239   *	@__sk_common: shared layout with inet_timewait_sock
240   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
241   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
242   *	@sk_lock:	synchronizer
243   *	@sk_kern_sock: True if sock is using kernel lock classes
244   *	@sk_rcvbuf: size of receive buffer in bytes
245   *	@sk_wq: sock wait queue and async head
246   *	@sk_rx_dst: receive input route used by early demux
247   *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
248   *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
249   *	@sk_dst_cache: destination cache
250   *	@sk_dst_pending_confirm: need to confirm neighbour
251   *	@sk_policy: flow policy
252   *	@sk_receive_queue: incoming packets
253   *	@sk_wmem_alloc: transmit queue bytes committed
254   *	@sk_tsq_flags: TCP Small Queues flags
255   *	@sk_write_queue: Packet sending queue
256   *	@sk_omem_alloc: "o" is "option" or "other"
257   *	@sk_wmem_queued: persistent queue size
258   *	@sk_forward_alloc: space allocated forward
259   *	@sk_reserved_mem: space reserved and non-reclaimable for the socket
260   *	@sk_napi_id: id of the last napi context to receive data for sk
261   *	@sk_ll_usec: usecs to busypoll when there is no data
262   *	@sk_allocation: allocation mode
263   *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
264   *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
265   *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
266   *	@sk_sndbuf: size of send buffer in bytes
267   *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
268   *	@sk_no_check_rx: allow zero checksum in RX packets
269   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
270   *	@sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
271   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
272   *	@sk_gso_max_size: Maximum GSO segment size to build
273   *	@sk_gso_max_segs: Maximum number of GSO segments
274   *	@sk_pacing_shift: scaling factor for TCP Small Queues
275   *	@sk_lingertime: %SO_LINGER l_linger setting
276   *	@sk_backlog: always used with the per-socket spinlock held
277   *	@sk_callback_lock: used with the callbacks in the end of this struct
278   *	@sk_error_queue: rarely used
279   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
280   *			  IPV6_ADDRFORM for instance)
281   *	@sk_err: last error
282   *	@sk_err_soft: errors that don't cause failure but are the cause of a
283   *		      persistent failure not just 'timed out'
284   *	@sk_drops: raw/udp drops counter
285   *	@sk_ack_backlog: current listen backlog
286   *	@sk_max_ack_backlog: listen backlog set in listen()
287   *	@sk_uid: user id of owner
288   *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
289   *	@sk_busy_poll_budget: napi processing budget when busypolling
290   *	@sk_priority: %SO_PRIORITY setting
291   *	@sk_type: socket type (%SOCK_STREAM, etc)
292   *	@sk_protocol: which protocol this socket belongs in this network family
293   *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
294   *	@sk_peer_pid: &struct pid for this socket's peer
295   *	@sk_peer_cred: %SO_PEERCRED setting
296   *	@sk_rcvlowat: %SO_RCVLOWAT setting
297   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
298   *	@sk_sndtimeo: %SO_SNDTIMEO setting
299   *	@sk_txhash: computed flow hash for use on transmit
300   *	@sk_txrehash: enable TX hash rethink
301   *	@sk_filter: socket filtering instructions
302   *	@sk_timer: sock cleanup timer
303   *	@sk_stamp: time stamp of last packet received
304   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
305   *	@sk_tsflags: SO_TIMESTAMPING flags
306   *	@sk_bpf_cb_flags: used in bpf_setsockopt()
307   *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
308   *			   Sockets that can be used under memory reclaim should
309   *			   set this to false.
310   *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
311   *	              for timestamping
312   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
313   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
314   *	@sk_socket: Identd and reporting IO signals
315   *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
316   *	@sk_frag: cached page frag
317   *	@sk_peek_off: current peek_offset value
318   *	@sk_send_head: front of stuff to transmit
319   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
320   *	@sk_security: used by security modules
321   *	@sk_mark: generic packet mark
322   *	@sk_cgrp_data: cgroup data for this cgroup
323   *	@sk_memcg: this socket's memory cgroup association
324   *	@sk_write_pending: a write to stream socket waits to start
325   *	@sk_disconnects: number of disconnect operations performed on this sock
326   *	@sk_state_change: callback to indicate change in the state of the sock
327   *	@sk_data_ready: callback to indicate there is data to be processed
328   *	@sk_write_space: callback to indicate there is bf sending space available
329   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
330   *	@sk_backlog_rcv: callback to process the backlog
331   *	@sk_validate_xmit_skb: ptr to an optional validate function
332   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
333   *	@sk_reuseport_cb: reuseport group container
334   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
335   *	@sk_rcu: used during RCU grace period
336   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
337   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
338   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
339   *	@sk_txtime_unused: unused txtime flags
340   *	@sk_scm_recv_flags: all flags used by scm_recv()
341   *	@sk_scm_credentials: flagged by SO_PASSCRED to recv SCM_CREDENTIALS
342   *	@sk_scm_security: flagged by SO_PASSSEC to recv SCM_SECURITY
343   *	@sk_scm_pidfd: flagged by SO_PASSPIDFD to recv SCM_PIDFD
344   *	@sk_scm_rights: flagged by SO_PASSRIGHTS to recv SCM_RIGHTS
345   *	@sk_scm_unused: unused flags for scm_recv()
346   *	@ns_tracker: tracker for netns reference
347   *	@sk_user_frags: xarray of pages the user is holding a reference on.
348   *	@sk_owner: reference to the real owner of the socket that calls
349   *		   sock_lock_init_class_and_name().
350   */
351 struct 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 	__cacheline_group_begin(sock_write_rx);
392 
393 	atomic_t		sk_drops;
394 	__s32			sk_peek_off;
395 	struct sk_buff_head	sk_error_queue;
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 	__cacheline_group_end(sock_write_rx);
414 
415 	__cacheline_group_begin(sock_read_rx);
416 	/* early demux fields */
417 	struct dst_entry __rcu	*sk_rx_dst;
418 	int			sk_rx_dst_ifindex;
419 	u32			sk_rx_dst_cookie;
420 
421 #ifdef CONFIG_NET_RX_BUSY_POLL
422 	unsigned int		sk_ll_usec;
423 	unsigned int		sk_napi_id;
424 	u16			sk_busy_poll_budget;
425 	u8			sk_prefer_busy_poll;
426 #endif
427 	u8			sk_userlocks;
428 	int			sk_rcvbuf;
429 
430 	struct sk_filter __rcu	*sk_filter;
431 	union {
432 		struct socket_wq __rcu	*sk_wq;
433 		/* private: */
434 		struct socket_wq	*sk_wq_raw;
435 		/* public: */
436 	};
437 
438 	void			(*sk_data_ready)(struct sock *sk);
439 	long			sk_rcvtimeo;
440 	int			sk_rcvlowat;
441 	__cacheline_group_end(sock_read_rx);
442 
443 	__cacheline_group_begin(sock_read_rxtx);
444 	int			sk_err;
445 	struct socket		*sk_socket;
446 	struct mem_cgroup	*sk_memcg;
447 #ifdef CONFIG_XFRM
448 	struct xfrm_policy __rcu *sk_policy[2];
449 #endif
450 	__cacheline_group_end(sock_read_rxtx);
451 
452 	__cacheline_group_begin(sock_write_rxtx);
453 	socket_lock_t		sk_lock;
454 	u32			sk_reserved_mem;
455 	int			sk_forward_alloc;
456 	u32			sk_tsflags;
457 	__cacheline_group_end(sock_write_rxtx);
458 
459 	__cacheline_group_begin(sock_write_tx);
460 	int			sk_write_pending;
461 	atomic_t		sk_omem_alloc;
462 	int			sk_sndbuf;
463 
464 	int			sk_wmem_queued;
465 	refcount_t		sk_wmem_alloc;
466 	unsigned long		sk_tsq_flags;
467 	union {
468 		struct sk_buff	*sk_send_head;
469 		struct rb_root	tcp_rtx_queue;
470 	};
471 	struct sk_buff_head	sk_write_queue;
472 	u32			sk_dst_pending_confirm;
473 	u32			sk_pacing_status; /* see enum sk_pacing */
474 	struct page_frag	sk_frag;
475 	struct timer_list	sk_timer;
476 
477 	unsigned long		sk_pacing_rate; /* bytes per second */
478 	atomic_t		sk_zckey;
479 	atomic_t		sk_tskey;
480 	__cacheline_group_end(sock_write_tx);
481 
482 	__cacheline_group_begin(sock_read_tx);
483 	unsigned long		sk_max_pacing_rate;
484 	long			sk_sndtimeo;
485 	u32			sk_priority;
486 	u32			sk_mark;
487 	struct dst_entry __rcu	*sk_dst_cache;
488 	netdev_features_t	sk_route_caps;
489 #ifdef CONFIG_SOCK_VALIDATE_XMIT
490 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
491 							struct net_device *dev,
492 							struct sk_buff *skb);
493 #endif
494 	u16			sk_gso_type;
495 	u16			sk_gso_max_segs;
496 	unsigned int		sk_gso_max_size;
497 	gfp_t			sk_allocation;
498 	u32			sk_txhash;
499 	u8			sk_pacing_shift;
500 	bool			sk_use_task_frag;
501 	__cacheline_group_end(sock_read_tx);
502 
503 	/*
504 	 * Because of non atomicity rules, all
505 	 * changes are protected by socket lock.
506 	 */
507 	u8			sk_gso_disabled : 1,
508 				sk_kern_sock : 1,
509 				sk_no_check_tx : 1,
510 				sk_no_check_rx : 1;
511 	u8			sk_shutdown;
512 	u16			sk_type;
513 	u16			sk_protocol;
514 	unsigned long	        sk_lingertime;
515 	struct proto		*sk_prot_creator;
516 	rwlock_t		sk_callback_lock;
517 	int			sk_err_soft;
518 	u32			sk_ack_backlog;
519 	u32			sk_max_ack_backlog;
520 	kuid_t			sk_uid;
521 	spinlock_t		sk_peer_lock;
522 	int			sk_bind_phc;
523 	struct pid		*sk_peer_pid;
524 	const struct cred	*sk_peer_cred;
525 
526 	ktime_t			sk_stamp;
527 #if BITS_PER_LONG==32
528 	seqlock_t		sk_stamp_seq;
529 #endif
530 	int			sk_disconnects;
531 
532 	union {
533 		u8		sk_txrehash;
534 		u8		sk_scm_recv_flags;
535 		struct {
536 			u8	sk_scm_credentials : 1,
537 				sk_scm_security : 1,
538 				sk_scm_pidfd : 1,
539 				sk_scm_rights : 1,
540 				sk_scm_unused : 4;
541 		};
542 	};
543 	u8			sk_clockid;
544 	u8			sk_txtime_deadline_mode : 1,
545 				sk_txtime_report_errors : 1,
546 				sk_txtime_unused : 6;
547 #define SK_BPF_CB_FLAG_TEST(SK, FLAG) ((SK)->sk_bpf_cb_flags & (FLAG))
548 	u8			sk_bpf_cb_flags;
549 
550 	void			*sk_user_data;
551 #ifdef CONFIG_SECURITY
552 	void			*sk_security;
553 #endif
554 	struct sock_cgroup_data	sk_cgrp_data;
555 	void			(*sk_state_change)(struct sock *sk);
556 	void			(*sk_write_space)(struct sock *sk);
557 	void			(*sk_error_report)(struct sock *sk);
558 	int			(*sk_backlog_rcv)(struct sock *sk,
559 						  struct sk_buff *skb);
560 	void                    (*sk_destruct)(struct sock *sk);
561 	struct sock_reuseport __rcu	*sk_reuseport_cb;
562 #ifdef CONFIG_BPF_SYSCALL
563 	struct bpf_local_storage __rcu	*sk_bpf_storage;
564 #endif
565 	struct rcu_head		sk_rcu;
566 	netns_tracker		ns_tracker;
567 	struct xarray		sk_user_frags;
568 
569 #if IS_ENABLED(CONFIG_PROVE_LOCKING) && IS_ENABLED(CONFIG_MODULES)
570 	struct module		*sk_owner;
571 #endif
572 };
573 
574 struct sock_bh_locked {
575 	struct sock *sock;
576 	local_lock_t bh_lock;
577 };
578 
579 enum sk_pacing {
580 	SK_PACING_NONE		= 0,
581 	SK_PACING_NEEDED	= 1,
582 	SK_PACING_FQ		= 2,
583 };
584 
585 /* flag bits in sk_user_data
586  *
587  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
588  *   not be suitable for copying when cloning the socket. For instance,
589  *   it can point to a reference counted object. sk_user_data bottom
590  *   bit is set if pointer must not be copied.
591  *
592  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
593  *   managed/owned by a BPF reuseport array. This bit should be set
594  *   when sk_user_data's sk is added to the bpf's reuseport_array.
595  *
596  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
597  *   sk_user_data points to psock type. This bit should be set
598  *   when sk_user_data is assigned to a psock object.
599  */
600 #define SK_USER_DATA_NOCOPY	1UL
601 #define SK_USER_DATA_BPF	2UL
602 #define SK_USER_DATA_PSOCK	4UL
603 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
604 				  SK_USER_DATA_PSOCK)
605 
606 /**
607  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
608  * @sk: socket
609  */
sk_user_data_is_nocopy(const struct sock * sk)610 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
611 {
612 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
613 }
614 
615 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
616 
617 /**
618  * __locked_read_sk_user_data_with_flags - return the pointer
619  * only if argument flags all has been set in sk_user_data. Otherwise
620  * return NULL
621  *
622  * @sk: socket
623  * @flags: flag bits
624  *
625  * The caller must be holding sk->sk_callback_lock.
626  */
627 static inline void *
__locked_read_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)628 __locked_read_sk_user_data_with_flags(const struct sock *sk,
629 				      uintptr_t flags)
630 {
631 	uintptr_t sk_user_data =
632 		(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
633 						 lockdep_is_held(&sk->sk_callback_lock));
634 
635 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
636 
637 	if ((sk_user_data & flags) == flags)
638 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
639 	return NULL;
640 }
641 
642 /**
643  * __rcu_dereference_sk_user_data_with_flags - return the pointer
644  * only if argument flags all has been set in sk_user_data. Otherwise
645  * return NULL
646  *
647  * @sk: socket
648  * @flags: flag bits
649  */
650 static inline void *
__rcu_dereference_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)651 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
652 					  uintptr_t flags)
653 {
654 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
655 
656 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
657 
658 	if ((sk_user_data & flags) == flags)
659 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
660 	return NULL;
661 }
662 
663 #define rcu_dereference_sk_user_data(sk)				\
664 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
665 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
666 ({									\
667 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
668 		  __tmp2 = (uintptr_t)(flags);				\
669 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
670 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
671 	rcu_assign_pointer(__sk_user_data((sk)),			\
672 			   __tmp1 | __tmp2);				\
673 })
674 #define rcu_assign_sk_user_data(sk, ptr)				\
675 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
676 
677 static inline
sock_net(const struct sock * sk)678 struct net *sock_net(const struct sock *sk)
679 {
680 	return read_pnet(&sk->sk_net);
681 }
682 
683 static inline
sock_net_set(struct sock * sk,struct net * net)684 void sock_net_set(struct sock *sk, struct net *net)
685 {
686 	write_pnet(&sk->sk_net, net);
687 }
688 
689 /*
690  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
691  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
692  * on a socket means that the socket will reuse everybody else's port
693  * without looking at the other's sk_reuse value.
694  */
695 
696 #define SK_NO_REUSE	0
697 #define SK_CAN_REUSE	1
698 #define SK_FORCE_REUSE	2
699 
700 int sk_set_peek_off(struct sock *sk, int val);
701 
sk_peek_offset(const struct sock * sk,int flags)702 static inline int sk_peek_offset(const struct sock *sk, int flags)
703 {
704 	if (unlikely(flags & MSG_PEEK)) {
705 		return READ_ONCE(sk->sk_peek_off);
706 	}
707 
708 	return 0;
709 }
710 
sk_peek_offset_bwd(struct sock * sk,int val)711 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
712 {
713 	s32 off = READ_ONCE(sk->sk_peek_off);
714 
715 	if (unlikely(off >= 0)) {
716 		off = max_t(s32, off - val, 0);
717 		WRITE_ONCE(sk->sk_peek_off, off);
718 	}
719 }
720 
sk_peek_offset_fwd(struct sock * sk,int val)721 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
722 {
723 	sk_peek_offset_bwd(sk, -val);
724 }
725 
726 /*
727  * Hashed lists helper routines
728  */
sk_entry(const struct hlist_node * node)729 static inline struct sock *sk_entry(const struct hlist_node *node)
730 {
731 	return hlist_entry(node, struct sock, sk_node);
732 }
733 
__sk_head(const struct hlist_head * head)734 static inline struct sock *__sk_head(const struct hlist_head *head)
735 {
736 	return hlist_entry(head->first, struct sock, sk_node);
737 }
738 
sk_head(const struct hlist_head * head)739 static inline struct sock *sk_head(const struct hlist_head *head)
740 {
741 	return hlist_empty(head) ? NULL : __sk_head(head);
742 }
743 
__sk_nulls_head(const struct hlist_nulls_head * head)744 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
745 {
746 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
747 }
748 
sk_nulls_head(const struct hlist_nulls_head * head)749 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
750 {
751 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
752 }
753 
sk_next(const struct sock * sk)754 static inline struct sock *sk_next(const struct sock *sk)
755 {
756 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
757 }
758 
sk_nulls_next(const struct sock * sk)759 static inline struct sock *sk_nulls_next(const struct sock *sk)
760 {
761 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
762 		hlist_nulls_entry(sk->sk_nulls_node.next,
763 				  struct sock, sk_nulls_node) :
764 		NULL;
765 }
766 
sk_unhashed(const struct sock * sk)767 static inline bool sk_unhashed(const struct sock *sk)
768 {
769 	return hlist_unhashed(&sk->sk_node);
770 }
771 
sk_hashed(const struct sock * sk)772 static inline bool sk_hashed(const struct sock *sk)
773 {
774 	return !sk_unhashed(sk);
775 }
776 
sk_node_init(struct hlist_node * node)777 static inline void sk_node_init(struct hlist_node *node)
778 {
779 	node->pprev = NULL;
780 }
781 
__sk_del_node(struct sock * sk)782 static inline void __sk_del_node(struct sock *sk)
783 {
784 	__hlist_del(&sk->sk_node);
785 }
786 
787 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)788 static inline bool __sk_del_node_init(struct sock *sk)
789 {
790 	if (sk_hashed(sk)) {
791 		__sk_del_node(sk);
792 		sk_node_init(&sk->sk_node);
793 		return true;
794 	}
795 	return false;
796 }
797 
798 /* Grab socket reference count. This operation is valid only
799    when sk is ALREADY grabbed f.e. it is found in hash table
800    or a list and the lookup is made under lock preventing hash table
801    modifications.
802  */
803 
sock_hold(struct sock * sk)804 static __always_inline void sock_hold(struct sock *sk)
805 {
806 	refcount_inc(&sk->sk_refcnt);
807 }
808 
809 /* Ungrab socket in the context, which assumes that socket refcnt
810    cannot hit zero, f.e. it is true in context of any socketcall.
811  */
__sock_put(struct sock * sk)812 static __always_inline void __sock_put(struct sock *sk)
813 {
814 	refcount_dec(&sk->sk_refcnt);
815 }
816 
sk_del_node_init(struct sock * sk)817 static inline bool sk_del_node_init(struct sock *sk)
818 {
819 	bool rc = __sk_del_node_init(sk);
820 
821 	if (rc) {
822 		/* paranoid for a while -acme */
823 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
824 		__sock_put(sk);
825 	}
826 	return rc;
827 }
828 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
829 
__sk_nulls_del_node_init_rcu(struct sock * sk)830 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
831 {
832 	if (sk_hashed(sk)) {
833 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
834 		return true;
835 	}
836 	return false;
837 }
838 
sk_nulls_del_node_init_rcu(struct sock * sk)839 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
840 {
841 	bool rc = __sk_nulls_del_node_init_rcu(sk);
842 
843 	if (rc) {
844 		/* paranoid for a while -acme */
845 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
846 		__sock_put(sk);
847 	}
848 	return rc;
849 }
850 
__sk_add_node(struct sock * sk,struct hlist_head * list)851 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
852 {
853 	hlist_add_head(&sk->sk_node, list);
854 }
855 
sk_add_node(struct sock * sk,struct hlist_head * list)856 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
857 {
858 	sock_hold(sk);
859 	__sk_add_node(sk, list);
860 }
861 
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)862 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
863 {
864 	sock_hold(sk);
865 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
866 	    sk->sk_family == AF_INET6)
867 		hlist_add_tail_rcu(&sk->sk_node, list);
868 	else
869 		hlist_add_head_rcu(&sk->sk_node, list);
870 }
871 
sk_add_node_tail_rcu(struct sock * sk,struct hlist_head * list)872 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
873 {
874 	sock_hold(sk);
875 	hlist_add_tail_rcu(&sk->sk_node, list);
876 }
877 
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)878 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
879 {
880 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
881 }
882 
__sk_nulls_add_node_tail_rcu(struct sock * sk,struct hlist_nulls_head * list)883 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
884 {
885 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
886 }
887 
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)888 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
889 {
890 	sock_hold(sk);
891 	__sk_nulls_add_node_rcu(sk, list);
892 }
893 
__sk_del_bind_node(struct sock * sk)894 static inline void __sk_del_bind_node(struct sock *sk)
895 {
896 	__hlist_del(&sk->sk_bind_node);
897 }
898 
sk_add_bind_node(struct sock * sk,struct hlist_head * list)899 static inline void sk_add_bind_node(struct sock *sk,
900 					struct hlist_head *list)
901 {
902 	hlist_add_head(&sk->sk_bind_node, list);
903 }
904 
905 #define sk_for_each(__sk, list) \
906 	hlist_for_each_entry(__sk, list, sk_node)
907 #define sk_for_each_rcu(__sk, list) \
908 	hlist_for_each_entry_rcu(__sk, list, sk_node)
909 #define sk_nulls_for_each(__sk, node, list) \
910 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
911 #define sk_nulls_for_each_rcu(__sk, node, list) \
912 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
913 #define sk_for_each_from(__sk) \
914 	hlist_for_each_entry_from(__sk, sk_node)
915 #define sk_nulls_for_each_from(__sk, node) \
916 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
917 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
918 #define sk_for_each_safe(__sk, tmp, list) \
919 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
920 #define sk_for_each_bound(__sk, list) \
921 	hlist_for_each_entry(__sk, list, sk_bind_node)
922 #define sk_for_each_bound_safe(__sk, tmp, list) \
923 	hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node)
924 
925 /**
926  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
927  * @tpos:	the type * to use as a loop cursor.
928  * @pos:	the &struct hlist_node to use as a loop cursor.
929  * @head:	the head for your list.
930  * @offset:	offset of hlist_node within the struct.
931  *
932  */
933 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
934 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
935 	     pos != NULL &&						       \
936 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
937 	     pos = rcu_dereference(hlist_next_rcu(pos)))
938 
sk_user_ns(const struct sock * sk)939 static inline struct user_namespace *sk_user_ns(const struct sock *sk)
940 {
941 	/* Careful only use this in a context where these parameters
942 	 * can not change and must all be valid, such as recvmsg from
943 	 * userspace.
944 	 */
945 	return sk->sk_socket->file->f_cred->user_ns;
946 }
947 
948 /* Sock flags */
949 enum sock_flags {
950 	SOCK_DEAD,
951 	SOCK_DONE,
952 	SOCK_URGINLINE,
953 	SOCK_KEEPOPEN,
954 	SOCK_LINGER,
955 	SOCK_DESTROY,
956 	SOCK_BROADCAST,
957 	SOCK_TIMESTAMP,
958 	SOCK_ZAPPED,
959 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
960 	SOCK_DBG, /* %SO_DEBUG setting */
961 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
962 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
963 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
964 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
965 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
966 	SOCK_FASYNC, /* fasync() active */
967 	SOCK_RXQ_OVFL,
968 	SOCK_ZEROCOPY, /* buffers from userspace */
969 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
970 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
971 		     * Will use last 4 bytes of packet sent from
972 		     * user-space instead.
973 		     */
974 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
975 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
976 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
977 	SOCK_TXTIME,
978 	SOCK_XDP, /* XDP is attached */
979 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
980 	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
981 	SOCK_RCVPRIORITY, /* Receive SO_PRIORITY ancillary data with packet */
982 	SOCK_TIMESTAMPING_ANY, /* Copy of sk_tsflags & TSFLAGS_ANY */
983 };
984 
985 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
986 /*
987  * The highest bit of sk_tsflags is reserved for kernel-internal
988  * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that
989  * SOF_TIMESTAMPING* values do not reach this reserved area
990  */
991 #define SOCKCM_FLAG_TS_OPT_ID	BIT(31)
992 
sock_copy_flags(struct sock * nsk,const struct sock * osk)993 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
994 {
995 	nsk->sk_flags = osk->sk_flags;
996 }
997 
sock_set_flag(struct sock * sk,enum sock_flags flag)998 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
999 {
1000 	__set_bit(flag, &sk->sk_flags);
1001 }
1002 
sock_reset_flag(struct sock * sk,enum sock_flags flag)1003 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
1004 {
1005 	__clear_bit(flag, &sk->sk_flags);
1006 }
1007 
sock_valbool_flag(struct sock * sk,enum sock_flags bit,int valbool)1008 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
1009 				     int valbool)
1010 {
1011 	if (valbool)
1012 		sock_set_flag(sk, bit);
1013 	else
1014 		sock_reset_flag(sk, bit);
1015 }
1016 
sock_flag(const struct sock * sk,enum sock_flags flag)1017 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
1018 {
1019 	return test_bit(flag, &sk->sk_flags);
1020 }
1021 
1022 #ifdef CONFIG_NET
1023 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
sk_memalloc_socks(void)1024 static inline int sk_memalloc_socks(void)
1025 {
1026 	return static_branch_unlikely(&memalloc_socks_key);
1027 }
1028 
1029 void __receive_sock(struct file *file);
1030 #else
1031 
sk_memalloc_socks(void)1032 static inline int sk_memalloc_socks(void)
1033 {
1034 	return 0;
1035 }
1036 
__receive_sock(struct file * file)1037 static inline void __receive_sock(struct file *file)
1038 { }
1039 #endif
1040 
sk_gfp_mask(const struct sock * sk,gfp_t gfp_mask)1041 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1042 {
1043 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1044 }
1045 
sk_acceptq_removed(struct sock * sk)1046 static inline void sk_acceptq_removed(struct sock *sk)
1047 {
1048 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1049 }
1050 
sk_acceptq_added(struct sock * sk)1051 static inline void sk_acceptq_added(struct sock *sk)
1052 {
1053 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1054 }
1055 
1056 /* Note: If you think the test should be:
1057  *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1058  * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1059  */
sk_acceptq_is_full(const struct sock * sk)1060 static inline bool sk_acceptq_is_full(const struct sock *sk)
1061 {
1062 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1063 }
1064 
1065 /*
1066  * Compute minimal free write space needed to queue new packets.
1067  */
sk_stream_min_wspace(const struct sock * sk)1068 static inline int sk_stream_min_wspace(const struct sock *sk)
1069 {
1070 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1071 }
1072 
sk_stream_wspace(const struct sock * sk)1073 static inline int sk_stream_wspace(const struct sock *sk)
1074 {
1075 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1076 }
1077 
sk_wmem_queued_add(struct sock * sk,int val)1078 static inline void sk_wmem_queued_add(struct sock *sk, int val)
1079 {
1080 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1081 }
1082 
sk_forward_alloc_add(struct sock * sk,int val)1083 static inline void sk_forward_alloc_add(struct sock *sk, int val)
1084 {
1085 	/* Paired with lockless reads of sk->sk_forward_alloc */
1086 	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1087 }
1088 
1089 void sk_stream_write_space(struct sock *sk);
1090 
1091 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)1092 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1093 {
1094 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1095 	skb_dst_force(skb);
1096 
1097 	if (!sk->sk_backlog.tail)
1098 		WRITE_ONCE(sk->sk_backlog.head, skb);
1099 	else
1100 		sk->sk_backlog.tail->next = skb;
1101 
1102 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1103 	skb->next = NULL;
1104 }
1105 
1106 /*
1107  * Take into account size of receive queue and backlog queue
1108  * Do not take into account this skb truesize,
1109  * to allow even a single big packet to come.
1110  */
sk_rcvqueues_full(const struct sock * sk,unsigned int limit)1111 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1112 {
1113 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1114 
1115 	return qsize > limit;
1116 }
1117 
1118 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb,unsigned int limit)1119 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1120 					      unsigned int limit)
1121 {
1122 	if (sk_rcvqueues_full(sk, limit))
1123 		return -ENOBUFS;
1124 
1125 	/*
1126 	 * If the skb was allocated from pfmemalloc reserves, only
1127 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1128 	 * helping free memory
1129 	 */
1130 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1131 		return -ENOMEM;
1132 
1133 	__sk_add_backlog(sk, skb);
1134 	sk->sk_backlog.len += skb->truesize;
1135 	return 0;
1136 }
1137 
1138 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1139 
1140 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1141 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1142 
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1143 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1144 {
1145 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1146 		return __sk_backlog_rcv(sk, skb);
1147 
1148 	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1149 				  tcp_v6_do_rcv,
1150 				  tcp_v4_do_rcv,
1151 				  sk, skb);
1152 }
1153 
sk_incoming_cpu_update(struct sock * sk)1154 static inline void sk_incoming_cpu_update(struct sock *sk)
1155 {
1156 	int cpu = raw_smp_processor_id();
1157 
1158 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1159 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1160 }
1161 
1162 
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1163 static inline void sock_rps_save_rxhash(struct sock *sk,
1164 					const struct sk_buff *skb)
1165 {
1166 #ifdef CONFIG_RPS
1167 	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1168 	 * here, and another one in sock_rps_record_flow().
1169 	 */
1170 	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1171 		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1172 #endif
1173 }
1174 
sock_rps_reset_rxhash(struct sock * sk)1175 static inline void sock_rps_reset_rxhash(struct sock *sk)
1176 {
1177 #ifdef CONFIG_RPS
1178 	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1179 	WRITE_ONCE(sk->sk_rxhash, 0);
1180 #endif
1181 }
1182 
1183 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1184 	({	int __rc, __dis = __sk->sk_disconnects;			\
1185 		release_sock(__sk);					\
1186 		__rc = __condition;					\
1187 		if (!__rc) {						\
1188 			*(__timeo) = wait_woken(__wait,			\
1189 						TASK_INTERRUPTIBLE,	\
1190 						*(__timeo));		\
1191 		}							\
1192 		sched_annotate_sleep();					\
1193 		lock_sock(__sk);					\
1194 		__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1195 		__rc;							\
1196 	})
1197 
1198 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1199 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1200 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1201 int sk_stream_error(struct sock *sk, int flags, int err);
1202 void sk_stream_kill_queues(struct sock *sk);
1203 void sk_set_memalloc(struct sock *sk);
1204 void sk_clear_memalloc(struct sock *sk);
1205 
1206 void __sk_flush_backlog(struct sock *sk);
1207 
sk_flush_backlog(struct sock * sk)1208 static inline bool sk_flush_backlog(struct sock *sk)
1209 {
1210 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1211 		__sk_flush_backlog(sk);
1212 		return true;
1213 	}
1214 	return false;
1215 }
1216 
1217 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1218 
1219 struct request_sock_ops;
1220 struct timewait_sock_ops;
1221 struct inet_hashinfo;
1222 struct raw_hashinfo;
1223 struct smc_hashinfo;
1224 struct module;
1225 struct sk_psock;
1226 
1227 /*
1228  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1229  * un-modified. Special care is taken when initializing object to zero.
1230  */
sk_prot_clear_nulls(struct sock * sk,int size)1231 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1232 {
1233 	if (offsetof(struct sock, sk_node.next) != 0)
1234 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1235 	memset(&sk->sk_node.pprev, 0,
1236 	       size - offsetof(struct sock, sk_node.pprev));
1237 }
1238 
1239 struct proto_accept_arg {
1240 	int flags;
1241 	int err;
1242 	int is_empty;
1243 	bool kern;
1244 };
1245 
1246 /* Networking protocol blocks we attach to sockets.
1247  * socket layer -> transport layer interface
1248  */
1249 struct proto {
1250 	void			(*close)(struct sock *sk,
1251 					long timeout);
1252 	int			(*pre_connect)(struct sock *sk,
1253 					struct sockaddr *uaddr,
1254 					int addr_len);
1255 	int			(*connect)(struct sock *sk,
1256 					struct sockaddr *uaddr,
1257 					int addr_len);
1258 	int			(*disconnect)(struct sock *sk, int flags);
1259 
1260 	struct sock *		(*accept)(struct sock *sk,
1261 					  struct proto_accept_arg *arg);
1262 
1263 	int			(*ioctl)(struct sock *sk, int cmd,
1264 					 int *karg);
1265 	int			(*init)(struct sock *sk);
1266 	void			(*destroy)(struct sock *sk);
1267 	void			(*shutdown)(struct sock *sk, int how);
1268 	int			(*setsockopt)(struct sock *sk, int level,
1269 					int optname, sockptr_t optval,
1270 					unsigned int optlen);
1271 	int			(*getsockopt)(struct sock *sk, int level,
1272 					int optname, char __user *optval,
1273 					int __user *option);
1274 	void			(*keepalive)(struct sock *sk, int valbool);
1275 #ifdef CONFIG_COMPAT
1276 	int			(*compat_ioctl)(struct sock *sk,
1277 					unsigned int cmd, unsigned long arg);
1278 #endif
1279 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1280 					   size_t len);
1281 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1282 					   size_t len, int flags, int *addr_len);
1283 	void			(*splice_eof)(struct socket *sock);
1284 	int			(*bind)(struct sock *sk,
1285 					struct sockaddr *addr, int addr_len);
1286 	int			(*bind_add)(struct sock *sk,
1287 					struct sockaddr *addr, int addr_len);
1288 
1289 	int			(*backlog_rcv) (struct sock *sk,
1290 						struct sk_buff *skb);
1291 	bool			(*bpf_bypass_getsockopt)(int level,
1292 							 int optname);
1293 
1294 	void		(*release_cb)(struct sock *sk);
1295 
1296 	/* Keeping track of sk's, looking them up, and port selection methods. */
1297 	int			(*hash)(struct sock *sk);
1298 	void			(*unhash)(struct sock *sk);
1299 	void			(*rehash)(struct sock *sk);
1300 	int			(*get_port)(struct sock *sk, unsigned short snum);
1301 	void			(*put_port)(struct sock *sk);
1302 #ifdef CONFIG_BPF_SYSCALL
1303 	int			(*psock_update_sk_prot)(struct sock *sk,
1304 							struct sk_psock *psock,
1305 							bool restore);
1306 #endif
1307 
1308 	/* Keeping track of sockets in use */
1309 #ifdef CONFIG_PROC_FS
1310 	unsigned int		inuse_idx;
1311 #endif
1312 
1313 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1314 	bool			(*sock_is_readable)(struct sock *sk);
1315 	/* Memory pressure */
1316 	void			(*enter_memory_pressure)(struct sock *sk);
1317 	void			(*leave_memory_pressure)(struct sock *sk);
1318 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1319 	int  __percpu		*per_cpu_fw_alloc;
1320 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1321 
1322 	/*
1323 	 * Pressure flag: try to collapse.
1324 	 * Technical note: it is used by multiple contexts non atomically.
1325 	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1326 	 * All the __sk_mem_schedule() is of this nature: accounting
1327 	 * is strict, actions are advisory and have some latency.
1328 	 */
1329 	unsigned long		*memory_pressure;
1330 	long			*sysctl_mem;
1331 
1332 	int			*sysctl_wmem;
1333 	int			*sysctl_rmem;
1334 	u32			sysctl_wmem_offset;
1335 	u32			sysctl_rmem_offset;
1336 
1337 	int			max_header;
1338 	bool			no_autobind;
1339 
1340 	struct kmem_cache	*slab;
1341 	unsigned int		obj_size;
1342 	unsigned int		ipv6_pinfo_offset;
1343 	slab_flags_t		slab_flags;
1344 	unsigned int		useroffset;	/* Usercopy region offset */
1345 	unsigned int		usersize;	/* Usercopy region size */
1346 
1347 	unsigned int __percpu	*orphan_count;
1348 
1349 	struct request_sock_ops	*rsk_prot;
1350 	struct timewait_sock_ops *twsk_prot;
1351 
1352 	union {
1353 		struct inet_hashinfo	*hashinfo;
1354 		struct udp_table	*udp_table;
1355 		struct raw_hashinfo	*raw_hash;
1356 		struct smc_hashinfo	*smc_hash;
1357 	} h;
1358 
1359 	struct module		*owner;
1360 
1361 	char			name[32];
1362 
1363 	struct list_head	node;
1364 	int			(*diag_destroy)(struct sock *sk, int err);
1365 } __randomize_layout;
1366 
1367 int proto_register(struct proto *prot, int alloc_slab);
1368 void proto_unregister(struct proto *prot);
1369 int sock_load_diag_module(int family, int protocol);
1370 
1371 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1372 
__sk_stream_memory_free(const struct sock * sk,int wake)1373 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1374 {
1375 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1376 		return false;
1377 
1378 	return sk->sk_prot->stream_memory_free ?
1379 		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1380 				     tcp_stream_memory_free, sk, wake) : true;
1381 }
1382 
sk_stream_memory_free(const struct sock * sk)1383 static inline bool sk_stream_memory_free(const struct sock *sk)
1384 {
1385 	return __sk_stream_memory_free(sk, 0);
1386 }
1387 
__sk_stream_is_writeable(const struct sock * sk,int wake)1388 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1389 {
1390 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1391 	       __sk_stream_memory_free(sk, wake);
1392 }
1393 
sk_stream_is_writeable(const struct sock * sk)1394 static inline bool sk_stream_is_writeable(const struct sock *sk)
1395 {
1396 	return __sk_stream_is_writeable(sk, 0);
1397 }
1398 
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1399 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1400 					    struct cgroup *ancestor)
1401 {
1402 #ifdef CONFIG_SOCK_CGROUP_DATA
1403 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1404 				    ancestor);
1405 #else
1406 	return -ENOTSUPP;
1407 #endif
1408 }
1409 
1410 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1411 
sk_sockets_allocated_dec(struct sock * sk)1412 static inline void sk_sockets_allocated_dec(struct sock *sk)
1413 {
1414 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1415 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1416 }
1417 
sk_sockets_allocated_inc(struct sock * sk)1418 static inline void sk_sockets_allocated_inc(struct sock *sk)
1419 {
1420 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1421 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1422 }
1423 
1424 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1425 sk_sockets_allocated_read_positive(struct sock *sk)
1426 {
1427 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1428 }
1429 
1430 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1431 proto_sockets_allocated_sum_positive(struct proto *prot)
1432 {
1433 	return percpu_counter_sum_positive(prot->sockets_allocated);
1434 }
1435 
1436 #ifdef CONFIG_PROC_FS
1437 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
1438 struct prot_inuse {
1439 	int all;
1440 	int val[PROTO_INUSE_NR];
1441 };
1442 
sock_prot_inuse_add(const struct net * net,const struct proto * prot,int val)1443 static inline void sock_prot_inuse_add(const struct net *net,
1444 				       const struct proto *prot, int val)
1445 {
1446 	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1447 }
1448 
sock_inuse_add(const struct net * net,int val)1449 static inline void sock_inuse_add(const struct net *net, int val)
1450 {
1451 	this_cpu_add(net->core.prot_inuse->all, val);
1452 }
1453 
1454 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1455 int sock_inuse_get(struct net *net);
1456 #else
sock_prot_inuse_add(const struct net * net,const struct proto * prot,int val)1457 static inline void sock_prot_inuse_add(const struct net *net,
1458 				       const struct proto *prot, int val)
1459 {
1460 }
1461 
sock_inuse_add(const struct net * net,int val)1462 static inline void sock_inuse_add(const struct net *net, int val)
1463 {
1464 }
1465 #endif
1466 
1467 
1468 /* With per-bucket locks this operation is not-atomic, so that
1469  * this version is not worse.
1470  */
__sk_prot_rehash(struct sock * sk)1471 static inline int __sk_prot_rehash(struct sock *sk)
1472 {
1473 	sk->sk_prot->unhash(sk);
1474 	return sk->sk_prot->hash(sk);
1475 }
1476 
1477 /* About 10 seconds */
1478 #define SOCK_DESTROY_TIME (10*HZ)
1479 
1480 /* Sockets 0-1023 can't be bound to unless you are superuser */
1481 #define PROT_SOCK	1024
1482 
1483 #define SHUTDOWN_MASK	3
1484 #define RCV_SHUTDOWN	1
1485 #define SEND_SHUTDOWN	2
1486 
1487 #define SOCK_BINDADDR_LOCK	4
1488 #define SOCK_BINDPORT_LOCK	8
1489 
1490 struct socket_alloc {
1491 	struct socket socket;
1492 	struct inode vfs_inode;
1493 };
1494 
SOCKET_I(struct inode * inode)1495 static inline struct socket *SOCKET_I(struct inode *inode)
1496 {
1497 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1498 }
1499 
SOCK_INODE(struct socket * socket)1500 static inline struct inode *SOCK_INODE(struct socket *socket)
1501 {
1502 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1503 }
1504 
1505 /*
1506  * Functions for memory accounting
1507  */
1508 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1509 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1510 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1511 void __sk_mem_reclaim(struct sock *sk, int amount);
1512 
1513 #define SK_MEM_SEND	0
1514 #define SK_MEM_RECV	1
1515 
1516 /* sysctl_mem values are in pages */
sk_prot_mem_limits(const struct sock * sk,int index)1517 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1518 {
1519 	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1520 }
1521 
sk_mem_pages(int amt)1522 static inline int sk_mem_pages(int amt)
1523 {
1524 	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1525 }
1526 
sk_has_account(struct sock * sk)1527 static inline bool sk_has_account(struct sock *sk)
1528 {
1529 	/* return true if protocol supports memory accounting */
1530 	return !!sk->sk_prot->memory_allocated;
1531 }
1532 
sk_wmem_schedule(struct sock * sk,int size)1533 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1534 {
1535 	int delta;
1536 
1537 	if (!sk_has_account(sk))
1538 		return true;
1539 	delta = size - sk->sk_forward_alloc;
1540 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1541 }
1542 
1543 static inline bool
__sk_rmem_schedule(struct sock * sk,int size,bool pfmemalloc)1544 __sk_rmem_schedule(struct sock *sk, int size, bool pfmemalloc)
1545 {
1546 	int delta;
1547 
1548 	if (!sk_has_account(sk))
1549 		return true;
1550 	delta = size - sk->sk_forward_alloc;
1551 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1552 	       pfmemalloc;
1553 }
1554 
1555 static inline bool
sk_rmem_schedule(struct sock * sk,struct sk_buff * skb,int size)1556 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1557 {
1558 	return __sk_rmem_schedule(sk, size, skb_pfmemalloc(skb));
1559 }
1560 
sk_unused_reserved_mem(const struct sock * sk)1561 static inline int sk_unused_reserved_mem(const struct sock *sk)
1562 {
1563 	int unused_mem;
1564 
1565 	if (likely(!sk->sk_reserved_mem))
1566 		return 0;
1567 
1568 	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1569 			atomic_read(&sk->sk_rmem_alloc);
1570 
1571 	return unused_mem > 0 ? unused_mem : 0;
1572 }
1573 
sk_mem_reclaim(struct sock * sk)1574 static inline void sk_mem_reclaim(struct sock *sk)
1575 {
1576 	int reclaimable;
1577 
1578 	if (!sk_has_account(sk))
1579 		return;
1580 
1581 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1582 
1583 	if (reclaimable >= (int)PAGE_SIZE)
1584 		__sk_mem_reclaim(sk, reclaimable);
1585 }
1586 
sk_mem_reclaim_final(struct sock * sk)1587 static inline void sk_mem_reclaim_final(struct sock *sk)
1588 {
1589 	sk->sk_reserved_mem = 0;
1590 	sk_mem_reclaim(sk);
1591 }
1592 
sk_mem_charge(struct sock * sk,int size)1593 static inline void sk_mem_charge(struct sock *sk, int size)
1594 {
1595 	if (!sk_has_account(sk))
1596 		return;
1597 	sk_forward_alloc_add(sk, -size);
1598 }
1599 
sk_mem_uncharge(struct sock * sk,int size)1600 static inline void sk_mem_uncharge(struct sock *sk, int size)
1601 {
1602 	if (!sk_has_account(sk))
1603 		return;
1604 	sk_forward_alloc_add(sk, size);
1605 	sk_mem_reclaim(sk);
1606 }
1607 
1608 #if IS_ENABLED(CONFIG_PROVE_LOCKING) && IS_ENABLED(CONFIG_MODULES)
sk_owner_set(struct sock * sk,struct module * owner)1609 static inline void sk_owner_set(struct sock *sk, struct module *owner)
1610 {
1611 	__module_get(owner);
1612 	sk->sk_owner = owner;
1613 }
1614 
sk_owner_clear(struct sock * sk)1615 static inline void sk_owner_clear(struct sock *sk)
1616 {
1617 	sk->sk_owner = NULL;
1618 }
1619 
sk_owner_put(struct sock * sk)1620 static inline void sk_owner_put(struct sock *sk)
1621 {
1622 	module_put(sk->sk_owner);
1623 }
1624 #else
sk_owner_set(struct sock * sk,struct module * owner)1625 static inline void sk_owner_set(struct sock *sk, struct module *owner)
1626 {
1627 }
1628 
sk_owner_clear(struct sock * sk)1629 static inline void sk_owner_clear(struct sock *sk)
1630 {
1631 }
1632 
sk_owner_put(struct sock * sk)1633 static inline void sk_owner_put(struct sock *sk)
1634 {
1635 }
1636 #endif
1637 /*
1638  * Macro so as to not evaluate some arguments when
1639  * lockdep is not enabled.
1640  *
1641  * Mark both the sk_lock and the sk_lock.slock as a
1642  * per-address-family lock class.
1643  */
1644 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1645 do {									\
1646 	sk_owner_set(sk, THIS_MODULE);					\
1647 	sk->sk_lock.owned = 0;						\
1648 	init_waitqueue_head(&sk->sk_lock.wq);				\
1649 	spin_lock_init(&(sk)->sk_lock.slock);				\
1650 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1651 				   sizeof((sk)->sk_lock));		\
1652 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1653 				   (skey), (sname));			\
1654 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1655 } while (0)
1656 
lockdep_sock_is_held(const struct sock * sk)1657 static inline bool lockdep_sock_is_held(const struct sock *sk)
1658 {
1659 	return lockdep_is_held(&sk->sk_lock) ||
1660 	       lockdep_is_held(&sk->sk_lock.slock);
1661 }
1662 
1663 void lock_sock_nested(struct sock *sk, int subclass);
1664 
lock_sock(struct sock * sk)1665 static inline void lock_sock(struct sock *sk)
1666 {
1667 	lock_sock_nested(sk, 0);
1668 }
1669 
1670 void __lock_sock(struct sock *sk);
1671 void __release_sock(struct sock *sk);
1672 void release_sock(struct sock *sk);
1673 
1674 /* BH context may only use the following locking interface. */
1675 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1676 #define bh_lock_sock_nested(__sk) \
1677 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1678 				SINGLE_DEPTH_NESTING)
1679 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1680 
1681 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1682 
1683 /**
1684  * lock_sock_fast - fast version of lock_sock
1685  * @sk: socket
1686  *
1687  * This version should be used for very small section, where process won't block
1688  * return false if fast path is taken:
1689  *
1690  *   sk_lock.slock locked, owned = 0, BH disabled
1691  *
1692  * return true if slow path is taken:
1693  *
1694  *   sk_lock.slock unlocked, owned = 1, BH enabled
1695  */
lock_sock_fast(struct sock * sk)1696 static inline bool lock_sock_fast(struct sock *sk)
1697 {
1698 	/* The sk_lock has mutex_lock() semantics here. */
1699 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1700 
1701 	return __lock_sock_fast(sk);
1702 }
1703 
1704 /* fast socket lock variant for caller already holding a [different] socket lock */
lock_sock_fast_nested(struct sock * sk)1705 static inline bool lock_sock_fast_nested(struct sock *sk)
1706 {
1707 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1708 
1709 	return __lock_sock_fast(sk);
1710 }
1711 
1712 /**
1713  * unlock_sock_fast - complement of lock_sock_fast
1714  * @sk: socket
1715  * @slow: slow mode
1716  *
1717  * fast unlock socket for user context.
1718  * If slow mode is on, we call regular release_sock()
1719  */
unlock_sock_fast(struct sock * sk,bool slow)1720 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1721 	__releases(&sk->sk_lock.slock)
1722 {
1723 	if (slow) {
1724 		release_sock(sk);
1725 		__release(&sk->sk_lock.slock);
1726 	} else {
1727 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1728 		spin_unlock_bh(&sk->sk_lock.slock);
1729 	}
1730 }
1731 
1732 void sockopt_lock_sock(struct sock *sk);
1733 void sockopt_release_sock(struct sock *sk);
1734 bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1735 bool sockopt_capable(int cap);
1736 
1737 /* Used by processes to "lock" a socket state, so that
1738  * interrupts and bottom half handlers won't change it
1739  * from under us. It essentially blocks any incoming
1740  * packets, so that we won't get any new data or any
1741  * packets that change the state of the socket.
1742  *
1743  * While locked, BH processing will add new packets to
1744  * the backlog queue.  This queue is processed by the
1745  * owner of the socket lock right before it is released.
1746  *
1747  * Since ~2.3.5 it is also exclusive sleep lock serializing
1748  * accesses from user process context.
1749  */
1750 
sock_owned_by_me(const struct sock * sk)1751 static inline void sock_owned_by_me(const struct sock *sk)
1752 {
1753 #ifdef CONFIG_LOCKDEP
1754 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1755 #endif
1756 }
1757 
sock_not_owned_by_me(const struct sock * sk)1758 static inline void sock_not_owned_by_me(const struct sock *sk)
1759 {
1760 #ifdef CONFIG_LOCKDEP
1761 	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1762 #endif
1763 }
1764 
sock_owned_by_user(const struct sock * sk)1765 static inline bool sock_owned_by_user(const struct sock *sk)
1766 {
1767 	sock_owned_by_me(sk);
1768 	return sk->sk_lock.owned;
1769 }
1770 
sock_owned_by_user_nocheck(const struct sock * sk)1771 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1772 {
1773 	return sk->sk_lock.owned;
1774 }
1775 
sock_release_ownership(struct sock * sk)1776 static inline void sock_release_ownership(struct sock *sk)
1777 {
1778 	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1779 	sk->sk_lock.owned = 0;
1780 
1781 	/* The sk_lock has mutex_unlock() semantics: */
1782 	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1783 }
1784 
1785 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1786 static inline bool sock_allow_reclassification(const struct sock *csk)
1787 {
1788 	struct sock *sk = (struct sock *)csk;
1789 
1790 	return !sock_owned_by_user_nocheck(sk) &&
1791 		!spin_is_locked(&sk->sk_lock.slock);
1792 }
1793 
1794 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1795 		      struct proto *prot, int kern);
1796 void sk_free(struct sock *sk);
1797 void sk_net_refcnt_upgrade(struct sock *sk);
1798 void sk_destruct(struct sock *sk);
1799 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1800 
1801 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1802 			     gfp_t priority);
1803 void __sock_wfree(struct sk_buff *skb);
1804 void sock_wfree(struct sk_buff *skb);
1805 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1806 			     gfp_t priority);
1807 void skb_orphan_partial(struct sk_buff *skb);
1808 void sock_rfree(struct sk_buff *skb);
1809 void sock_efree(struct sk_buff *skb);
1810 #ifdef CONFIG_INET
1811 void sock_edemux(struct sk_buff *skb);
1812 void sock_pfree(struct sk_buff *skb);
1813 
skb_set_owner_edemux(struct sk_buff * skb,struct sock * sk)1814 static inline void skb_set_owner_edemux(struct sk_buff *skb, struct sock *sk)
1815 {
1816 	skb_orphan(skb);
1817 	if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1818 		skb->sk = sk;
1819 		skb->destructor = sock_edemux;
1820 	}
1821 }
1822 #else
1823 #define sock_edemux sock_efree
1824 #endif
1825 
1826 int sk_setsockopt(struct sock *sk, int level, int optname,
1827 		  sockptr_t optval, unsigned int optlen);
1828 int sock_setsockopt(struct socket *sock, int level, int op,
1829 		    sockptr_t optval, unsigned int optlen);
1830 int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1831 		       int optname, sockptr_t optval, int optlen);
1832 int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1833 		       int optname, sockptr_t optval, sockptr_t optlen);
1834 
1835 int sk_getsockopt(struct sock *sk, int level, int optname,
1836 		  sockptr_t optval, sockptr_t optlen);
1837 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1838 		   bool timeval, bool time32);
1839 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1840 				     unsigned long data_len, int noblock,
1841 				     int *errcode, int max_page_order);
1842 
sock_alloc_send_skb(struct sock * sk,unsigned long size,int noblock,int * errcode)1843 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1844 						  unsigned long size,
1845 						  int noblock, int *errcode)
1846 {
1847 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1848 }
1849 
1850 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1851 void *sock_kmemdup(struct sock *sk, const void *src,
1852 		   int size, gfp_t priority);
1853 void sock_kfree_s(struct sock *sk, void *mem, int size);
1854 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1855 void sk_send_sigurg(struct sock *sk);
1856 
sock_replace_proto(struct sock * sk,struct proto * proto)1857 static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1858 {
1859 	if (sk->sk_socket)
1860 		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1861 	WRITE_ONCE(sk->sk_prot, proto);
1862 }
1863 
1864 struct sockcm_cookie {
1865 	u64 transmit_time;
1866 	u32 mark;
1867 	u32 tsflags;
1868 	u32 ts_opt_id;
1869 	u32 priority;
1870 	u32 dmabuf_id;
1871 };
1872 
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1873 static inline void sockcm_init(struct sockcm_cookie *sockc,
1874 			       const struct sock *sk)
1875 {
1876 	*sockc = (struct sockcm_cookie) {
1877 		.mark = READ_ONCE(sk->sk_mark),
1878 		.tsflags = READ_ONCE(sk->sk_tsflags),
1879 		.priority = READ_ONCE(sk->sk_priority),
1880 	};
1881 }
1882 
1883 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1884 		     struct sockcm_cookie *sockc);
1885 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1886 		   struct sockcm_cookie *sockc);
1887 
1888 /*
1889  * Functions to fill in entries in struct proto_ops when a protocol
1890  * does not implement a particular function.
1891  */
1892 int sock_no_bind(struct socket *, struct sockaddr *, int);
1893 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1894 int sock_no_socketpair(struct socket *, struct socket *);
1895 int sock_no_accept(struct socket *, struct socket *, struct proto_accept_arg *);
1896 int sock_no_getname(struct socket *, struct sockaddr *, int);
1897 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1898 int sock_no_listen(struct socket *, int);
1899 int sock_no_shutdown(struct socket *, int);
1900 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1901 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1902 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1903 int sock_no_mmap(struct file *file, struct socket *sock,
1904 		 struct vm_area_struct *vma);
1905 
1906 /*
1907  * Functions to fill in entries in struct proto_ops when a protocol
1908  * uses the inet style.
1909  */
1910 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1911 				  char __user *optval, int __user *optlen);
1912 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1913 			int flags);
1914 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1915 			   sockptr_t optval, unsigned int optlen);
1916 
1917 void sk_common_release(struct sock *sk);
1918 
1919 /*
1920  *	Default socket callbacks and setup code
1921  */
1922 
1923 /* Initialise core socket variables using an explicit uid. */
1924 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1925 
1926 /* Initialise core socket variables.
1927  * Assumes struct socket *sock is embedded in a struct socket_alloc.
1928  */
1929 void sock_init_data(struct socket *sock, struct sock *sk);
1930 
1931 /*
1932  * Socket reference counting postulates.
1933  *
1934  * * Each user of socket SHOULD hold a reference count.
1935  * * Each access point to socket (an hash table bucket, reference from a list,
1936  *   running timer, skb in flight MUST hold a reference count.
1937  * * When reference count hits 0, it means it will never increase back.
1938  * * When reference count hits 0, it means that no references from
1939  *   outside exist to this socket and current process on current CPU
1940  *   is last user and may/should destroy this socket.
1941  * * sk_free is called from any context: process, BH, IRQ. When
1942  *   it is called, socket has no references from outside -> sk_free
1943  *   may release descendant resources allocated by the socket, but
1944  *   to the time when it is called, socket is NOT referenced by any
1945  *   hash tables, lists etc.
1946  * * Packets, delivered from outside (from network or from another process)
1947  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1948  *   when they sit in queue. Otherwise, packets will leak to hole, when
1949  *   socket is looked up by one cpu and unhasing is made by another CPU.
1950  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1951  *   (leak to backlog). Packet socket does all the processing inside
1952  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1953  *   use separate SMP lock, so that they are prone too.
1954  */
1955 
1956 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1957 static inline void sock_put(struct sock *sk)
1958 {
1959 	if (refcount_dec_and_test(&sk->sk_refcnt))
1960 		sk_free(sk);
1961 }
1962 /* Generic version of sock_put(), dealing with all sockets
1963  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1964  */
1965 void sock_gen_put(struct sock *sk);
1966 
1967 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1968 		     unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1969 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1970 				 const int nested)
1971 {
1972 	return __sk_receive_skb(sk, skb, nested, 1, true);
1973 }
1974 
sk_tx_queue_set(struct sock * sk,int tx_queue)1975 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1976 {
1977 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1978 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1979 		return;
1980 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1981 	 * other WRITE_ONCE() because socket lock might be not held.
1982 	 */
1983 	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1984 }
1985 
1986 #define NO_QUEUE_MAPPING	USHRT_MAX
1987 
sk_tx_queue_clear(struct sock * sk)1988 static inline void sk_tx_queue_clear(struct sock *sk)
1989 {
1990 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1991 	 * other WRITE_ONCE() because socket lock might be not held.
1992 	 */
1993 	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1994 }
1995 
sk_tx_queue_get(const struct sock * sk)1996 static inline int sk_tx_queue_get(const struct sock *sk)
1997 {
1998 	if (sk) {
1999 		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
2000 		 * and sk_tx_queue_set().
2001 		 */
2002 		int val = READ_ONCE(sk->sk_tx_queue_mapping);
2003 
2004 		if (val != NO_QUEUE_MAPPING)
2005 			return val;
2006 	}
2007 	return -1;
2008 }
2009 
__sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb,bool force_set)2010 static inline void __sk_rx_queue_set(struct sock *sk,
2011 				     const struct sk_buff *skb,
2012 				     bool force_set)
2013 {
2014 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2015 	if (skb_rx_queue_recorded(skb)) {
2016 		u16 rx_queue = skb_get_rx_queue(skb);
2017 
2018 		if (force_set ||
2019 		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2020 			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2021 	}
2022 #endif
2023 }
2024 
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)2025 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2026 {
2027 	__sk_rx_queue_set(sk, skb, true);
2028 }
2029 
sk_rx_queue_update(struct sock * sk,const struct sk_buff * skb)2030 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2031 {
2032 	__sk_rx_queue_set(sk, skb, false);
2033 }
2034 
sk_rx_queue_clear(struct sock * sk)2035 static inline void sk_rx_queue_clear(struct sock *sk)
2036 {
2037 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2038 	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2039 #endif
2040 }
2041 
sk_rx_queue_get(const struct sock * sk)2042 static inline int sk_rx_queue_get(const struct sock *sk)
2043 {
2044 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2045 	if (sk) {
2046 		int res = READ_ONCE(sk->sk_rx_queue_mapping);
2047 
2048 		if (res != NO_QUEUE_MAPPING)
2049 			return res;
2050 	}
2051 #endif
2052 
2053 	return -1;
2054 }
2055 
sk_set_socket(struct sock * sk,struct socket * sock)2056 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2057 {
2058 	sk->sk_socket = sock;
2059 }
2060 
sk_sleep(struct sock * sk)2061 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2062 {
2063 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2064 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2065 }
2066 /* Detach socket from process context.
2067  * Announce socket dead, detach it from wait queue and inode.
2068  * Note that parent inode held reference count on this struct sock,
2069  * we do not release it in this function, because protocol
2070  * probably wants some additional cleanups or even continuing
2071  * to work with this socket (TCP).
2072  */
sock_orphan(struct sock * sk)2073 static inline void sock_orphan(struct sock *sk)
2074 {
2075 	write_lock_bh(&sk->sk_callback_lock);
2076 	sock_set_flag(sk, SOCK_DEAD);
2077 	sk_set_socket(sk, NULL);
2078 	sk->sk_wq  = NULL;
2079 	write_unlock_bh(&sk->sk_callback_lock);
2080 }
2081 
sock_graft(struct sock * sk,struct socket * parent)2082 static inline void sock_graft(struct sock *sk, struct socket *parent)
2083 {
2084 	WARN_ON(parent->sk);
2085 	write_lock_bh(&sk->sk_callback_lock);
2086 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2087 	parent->sk = sk;
2088 	sk_set_socket(sk, parent);
2089 	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2090 	security_sock_graft(sk, parent);
2091 	write_unlock_bh(&sk->sk_callback_lock);
2092 }
2093 
2094 kuid_t sock_i_uid(struct sock *sk);
2095 unsigned long __sock_i_ino(struct sock *sk);
2096 unsigned long sock_i_ino(struct sock *sk);
2097 
sock_net_uid(const struct net * net,const struct sock * sk)2098 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2099 {
2100 	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2101 }
2102 
net_tx_rndhash(void)2103 static inline u32 net_tx_rndhash(void)
2104 {
2105 	u32 v = get_random_u32();
2106 
2107 	return v ?: 1;
2108 }
2109 
sk_set_txhash(struct sock * sk)2110 static inline void sk_set_txhash(struct sock *sk)
2111 {
2112 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2113 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2114 }
2115 
sk_rethink_txhash(struct sock * sk)2116 static inline bool sk_rethink_txhash(struct sock *sk)
2117 {
2118 	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2119 		sk_set_txhash(sk);
2120 		return true;
2121 	}
2122 	return false;
2123 }
2124 
2125 static inline struct dst_entry *
__sk_dst_get(const struct sock * sk)2126 __sk_dst_get(const struct sock *sk)
2127 {
2128 	return rcu_dereference_check(sk->sk_dst_cache,
2129 				     lockdep_sock_is_held(sk));
2130 }
2131 
2132 static inline struct dst_entry *
sk_dst_get(const struct sock * sk)2133 sk_dst_get(const struct sock *sk)
2134 {
2135 	struct dst_entry *dst;
2136 
2137 	rcu_read_lock();
2138 	dst = rcu_dereference(sk->sk_dst_cache);
2139 	if (dst && !rcuref_get(&dst->__rcuref))
2140 		dst = NULL;
2141 	rcu_read_unlock();
2142 	return dst;
2143 }
2144 
__dst_negative_advice(struct sock * sk)2145 static inline void __dst_negative_advice(struct sock *sk)
2146 {
2147 	struct dst_entry *dst = __sk_dst_get(sk);
2148 
2149 	if (dst && dst->ops->negative_advice)
2150 		dst->ops->negative_advice(sk, dst);
2151 }
2152 
dst_negative_advice(struct sock * sk)2153 static inline void dst_negative_advice(struct sock *sk)
2154 {
2155 	sk_rethink_txhash(sk);
2156 	__dst_negative_advice(sk);
2157 }
2158 
2159 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)2160 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2161 {
2162 	struct dst_entry *old_dst;
2163 
2164 	sk_tx_queue_clear(sk);
2165 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2166 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2167 					    lockdep_sock_is_held(sk));
2168 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2169 	dst_release(old_dst);
2170 }
2171 
2172 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2173 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2174 {
2175 	struct dst_entry *old_dst;
2176 
2177 	sk_tx_queue_clear(sk);
2178 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2179 	old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst)));
2180 	dst_release(old_dst);
2181 }
2182 
2183 static inline void
__sk_dst_reset(struct sock * sk)2184 __sk_dst_reset(struct sock *sk)
2185 {
2186 	__sk_dst_set(sk, NULL);
2187 }
2188 
2189 static inline void
sk_dst_reset(struct sock * sk)2190 sk_dst_reset(struct sock *sk)
2191 {
2192 	sk_dst_set(sk, NULL);
2193 }
2194 
2195 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2196 
2197 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2198 
sk_dst_confirm(struct sock * sk)2199 static inline void sk_dst_confirm(struct sock *sk)
2200 {
2201 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2202 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2203 }
2204 
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2205 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2206 {
2207 	if (skb_get_dst_pending_confirm(skb)) {
2208 		struct sock *sk = skb->sk;
2209 
2210 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2211 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2212 		neigh_confirm(n);
2213 	}
2214 }
2215 
2216 bool sk_mc_loop(const struct sock *sk);
2217 
sk_can_gso(const struct sock * sk)2218 static inline bool sk_can_gso(const struct sock *sk)
2219 {
2220 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2221 }
2222 
2223 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2224 
sk_gso_disable(struct sock * sk)2225 static inline void sk_gso_disable(struct sock *sk)
2226 {
2227 	sk->sk_gso_disabled = 1;
2228 	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2229 }
2230 
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2231 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2232 					   struct iov_iter *from, char *to,
2233 					   int copy, int offset)
2234 {
2235 	if (skb->ip_summed == CHECKSUM_NONE) {
2236 		__wsum csum = 0;
2237 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2238 			return -EFAULT;
2239 		skb->csum = csum_block_add(skb->csum, csum, offset);
2240 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2241 		if (!copy_from_iter_full_nocache(to, copy, from))
2242 			return -EFAULT;
2243 	} else if (!copy_from_iter_full(to, copy, from))
2244 		return -EFAULT;
2245 
2246 	return 0;
2247 }
2248 
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2249 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2250 				       struct iov_iter *from, int copy)
2251 {
2252 	int err, offset = skb->len;
2253 
2254 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2255 				       copy, offset);
2256 	if (err)
2257 		__skb_trim(skb, offset);
2258 
2259 	return err;
2260 }
2261 
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2262 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2263 					   struct sk_buff *skb,
2264 					   struct page *page,
2265 					   int off, int copy)
2266 {
2267 	int err;
2268 
2269 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2270 				       copy, skb->len);
2271 	if (err)
2272 		return err;
2273 
2274 	skb_len_add(skb, copy);
2275 	sk_wmem_queued_add(sk, copy);
2276 	sk_mem_charge(sk, copy);
2277 	return 0;
2278 }
2279 
2280 /**
2281  * sk_wmem_alloc_get - returns write allocations
2282  * @sk: socket
2283  *
2284  * Return: sk_wmem_alloc minus initial offset of one
2285  */
sk_wmem_alloc_get(const struct sock * sk)2286 static inline int sk_wmem_alloc_get(const struct sock *sk)
2287 {
2288 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2289 }
2290 
2291 /**
2292  * sk_rmem_alloc_get - returns read allocations
2293  * @sk: socket
2294  *
2295  * Return: sk_rmem_alloc
2296  */
sk_rmem_alloc_get(const struct sock * sk)2297 static inline int sk_rmem_alloc_get(const struct sock *sk)
2298 {
2299 	return atomic_read(&sk->sk_rmem_alloc);
2300 }
2301 
2302 /**
2303  * sk_has_allocations - check if allocations are outstanding
2304  * @sk: socket
2305  *
2306  * Return: true if socket has write or read allocations
2307  */
sk_has_allocations(const struct sock * sk)2308 static inline bool sk_has_allocations(const struct sock *sk)
2309 {
2310 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2311 }
2312 
2313 /**
2314  * skwq_has_sleeper - check if there are any waiting processes
2315  * @wq: struct socket_wq
2316  *
2317  * Return: true if socket_wq has waiting processes
2318  *
2319  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2320  * barrier call. They were added due to the race found within the tcp code.
2321  *
2322  * Consider following tcp code paths::
2323  *
2324  *   CPU1                CPU2
2325  *   sys_select          receive packet
2326  *   ...                 ...
2327  *   __add_wait_queue    update tp->rcv_nxt
2328  *   ...                 ...
2329  *   tp->rcv_nxt check   sock_def_readable
2330  *   ...                 {
2331  *   schedule               rcu_read_lock();
2332  *                          wq = rcu_dereference(sk->sk_wq);
2333  *                          if (wq && waitqueue_active(&wq->wait))
2334  *                              wake_up_interruptible(&wq->wait)
2335  *                          ...
2336  *                       }
2337  *
2338  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2339  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2340  * could then endup calling schedule and sleep forever if there are no more
2341  * data on the socket.
2342  *
2343  */
skwq_has_sleeper(struct socket_wq * wq)2344 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2345 {
2346 	return wq && wq_has_sleeper(&wq->wait);
2347 }
2348 
2349 /**
2350  * sock_poll_wait - wrapper for the poll_wait call.
2351  * @filp:           file
2352  * @sock:           socket to wait on
2353  * @p:              poll_table
2354  *
2355  * See the comments in the wq_has_sleeper function.
2356  */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2357 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2358 				  poll_table *p)
2359 {
2360 	/* Provides a barrier we need to be sure we are in sync
2361 	 * with the socket flags modification.
2362 	 *
2363 	 * This memory barrier is paired in the wq_has_sleeper.
2364 	 */
2365 	poll_wait(filp, &sock->wq.wait, p);
2366 }
2367 
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2368 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2369 {
2370 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2371 	u32 txhash = READ_ONCE(sk->sk_txhash);
2372 
2373 	if (txhash) {
2374 		skb->l4_hash = 1;
2375 		skb->hash = txhash;
2376 	}
2377 }
2378 
2379 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2380 
2381 /*
2382  *	Queue a received datagram if it will fit. Stream and sequenced
2383  *	protocols can't normally use this as they need to fit buffers in
2384  *	and play with them.
2385  *
2386  *	Inlined as it's very short and called for pretty much every
2387  *	packet ever received.
2388  */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2389 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2390 {
2391 	skb_orphan(skb);
2392 	skb->sk = sk;
2393 	skb->destructor = sock_rfree;
2394 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2395 	sk_mem_charge(sk, skb->truesize);
2396 }
2397 
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2398 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2399 {
2400 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2401 		skb_orphan(skb);
2402 		skb->destructor = sock_efree;
2403 		skb->sk = sk;
2404 		return true;
2405 	}
2406 	return false;
2407 }
2408 
skb_clone_and_charge_r(struct sk_buff * skb,struct sock * sk)2409 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2410 {
2411 	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2412 	if (skb) {
2413 		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2414 			skb_set_owner_r(skb, sk);
2415 			return skb;
2416 		}
2417 		__kfree_skb(skb);
2418 	}
2419 	return NULL;
2420 }
2421 
skb_prepare_for_gro(struct sk_buff * skb)2422 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2423 {
2424 	if (skb->destructor != sock_wfree) {
2425 		skb_orphan(skb);
2426 		return;
2427 	}
2428 	skb->slow_gro = 1;
2429 }
2430 
2431 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2432 		    unsigned long expires);
2433 
2434 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2435 
2436 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2437 
2438 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2439 			struct sk_buff *skb, unsigned int flags,
2440 			void (*destructor)(struct sock *sk,
2441 					   struct sk_buff *skb));
2442 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2443 
2444 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2445 			      enum skb_drop_reason *reason);
2446 
sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)2447 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2448 {
2449 	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2450 }
2451 
2452 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2453 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2454 
2455 /*
2456  *	Recover an error report and clear atomically
2457  */
2458 
sock_error(struct sock * sk)2459 static inline int sock_error(struct sock *sk)
2460 {
2461 	int err;
2462 
2463 	/* Avoid an atomic operation for the common case.
2464 	 * This is racy since another cpu/thread can change sk_err under us.
2465 	 */
2466 	if (likely(data_race(!sk->sk_err)))
2467 		return 0;
2468 
2469 	err = xchg(&sk->sk_err, 0);
2470 	return -err;
2471 }
2472 
2473 void sk_error_report(struct sock *sk);
2474 
sock_wspace(struct sock * sk)2475 static inline unsigned long sock_wspace(struct sock *sk)
2476 {
2477 	int amt = 0;
2478 
2479 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2480 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2481 		if (amt < 0)
2482 			amt = 0;
2483 	}
2484 	return amt;
2485 }
2486 
2487 /* Note:
2488  *  We use sk->sk_wq_raw, from contexts knowing this
2489  *  pointer is not NULL and cannot disappear/change.
2490  */
sk_set_bit(int nr,struct sock * sk)2491 static inline void sk_set_bit(int nr, struct sock *sk)
2492 {
2493 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2494 	    !sock_flag(sk, SOCK_FASYNC))
2495 		return;
2496 
2497 	set_bit(nr, &sk->sk_wq_raw->flags);
2498 }
2499 
sk_clear_bit(int nr,struct sock * sk)2500 static inline void sk_clear_bit(int nr, struct sock *sk)
2501 {
2502 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2503 	    !sock_flag(sk, SOCK_FASYNC))
2504 		return;
2505 
2506 	clear_bit(nr, &sk->sk_wq_raw->flags);
2507 }
2508 
sk_wake_async(const struct sock * sk,int how,int band)2509 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2510 {
2511 	if (sock_flag(sk, SOCK_FASYNC)) {
2512 		rcu_read_lock();
2513 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2514 		rcu_read_unlock();
2515 	}
2516 }
2517 
sk_wake_async_rcu(const struct sock * sk,int how,int band)2518 static inline void sk_wake_async_rcu(const struct sock *sk, int how, int band)
2519 {
2520 	if (unlikely(sock_flag(sk, SOCK_FASYNC)))
2521 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2522 }
2523 
2524 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2525  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2526  * Note: for send buffers, TCP works better if we can build two skbs at
2527  * minimum.
2528  */
2529 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2530 
2531 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2532 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2533 
sk_stream_moderate_sndbuf(struct sock * sk)2534 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2535 {
2536 	u32 val;
2537 
2538 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2539 		return;
2540 
2541 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2542 	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2543 
2544 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2545 }
2546 
2547 /**
2548  * sk_page_frag - return an appropriate page_frag
2549  * @sk: socket
2550  *
2551  * Use the per task page_frag instead of the per socket one for
2552  * optimization when we know that we're in process context and own
2553  * everything that's associated with %current.
2554  *
2555  * Both direct reclaim and page faults can nest inside other
2556  * socket operations and end up recursing into sk_page_frag()
2557  * while it's already in use: explicitly avoid task page_frag
2558  * when users disable sk_use_task_frag.
2559  *
2560  * Return: a per task page_frag if context allows that,
2561  * otherwise a per socket one.
2562  */
sk_page_frag(struct sock * sk)2563 static inline struct page_frag *sk_page_frag(struct sock *sk)
2564 {
2565 	if (sk->sk_use_task_frag)
2566 		return &current->task_frag;
2567 
2568 	return &sk->sk_frag;
2569 }
2570 
2571 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2572 
2573 /*
2574  *	Default write policy as shown to user space via poll/select/SIGIO
2575  */
sock_writeable(const struct sock * sk)2576 static inline bool sock_writeable(const struct sock *sk)
2577 {
2578 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2579 }
2580 
gfp_any(void)2581 static inline gfp_t gfp_any(void)
2582 {
2583 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2584 }
2585 
gfp_memcg_charge(void)2586 static inline gfp_t gfp_memcg_charge(void)
2587 {
2588 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2589 }
2590 
sock_rcvtimeo(const struct sock * sk,bool noblock)2591 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2592 {
2593 	return noblock ? 0 : sk->sk_rcvtimeo;
2594 }
2595 
sock_sndtimeo(const struct sock * sk,bool noblock)2596 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2597 {
2598 	return noblock ? 0 : sk->sk_sndtimeo;
2599 }
2600 
sock_rcvlowat(const struct sock * sk,int waitall,int len)2601 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2602 {
2603 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2604 
2605 	return v ?: 1;
2606 }
2607 
2608 /* Alas, with timeout socket operations are not restartable.
2609  * Compare this to poll().
2610  */
sock_intr_errno(long timeo)2611 static inline int sock_intr_errno(long timeo)
2612 {
2613 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2614 }
2615 
2616 struct sock_skb_cb {
2617 	u32 dropcount;
2618 };
2619 
2620 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2621  * using skb->cb[] would keep using it directly and utilize its
2622  * alignment guarantee.
2623  */
2624 #define SOCK_SKB_CB_OFFSET (sizeof_field(struct sk_buff, cb) - \
2625 			    sizeof(struct sock_skb_cb))
2626 
2627 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2628 			    SOCK_SKB_CB_OFFSET))
2629 
2630 #define sock_skb_cb_check_size(size) \
2631 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2632 
2633 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2634 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2635 {
2636 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2637 						atomic_read(&sk->sk_drops) : 0;
2638 }
2639 
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2640 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2641 {
2642 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2643 
2644 	atomic_add(segs, &sk->sk_drops);
2645 }
2646 
sock_read_timestamp(struct sock * sk)2647 static inline ktime_t sock_read_timestamp(struct sock *sk)
2648 {
2649 #if BITS_PER_LONG==32
2650 	unsigned int seq;
2651 	ktime_t kt;
2652 
2653 	do {
2654 		seq = read_seqbegin(&sk->sk_stamp_seq);
2655 		kt = sk->sk_stamp;
2656 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2657 
2658 	return kt;
2659 #else
2660 	return READ_ONCE(sk->sk_stamp);
2661 #endif
2662 }
2663 
sock_write_timestamp(struct sock * sk,ktime_t kt)2664 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2665 {
2666 #if BITS_PER_LONG==32
2667 	write_seqlock(&sk->sk_stamp_seq);
2668 	sk->sk_stamp = kt;
2669 	write_sequnlock(&sk->sk_stamp_seq);
2670 #else
2671 	WRITE_ONCE(sk->sk_stamp, kt);
2672 #endif
2673 }
2674 
2675 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2676 			   struct sk_buff *skb);
2677 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2678 			     struct sk_buff *skb);
2679 
2680 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2681 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2682 {
2683 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2684 	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2685 	ktime_t kt = skb->tstamp;
2686 	/*
2687 	 * generate control messages if
2688 	 * - receive time stamping in software requested
2689 	 * - software time stamp available and wanted
2690 	 * - hardware time stamps available and wanted
2691 	 */
2692 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2693 	    (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2694 	    (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2695 	    (hwtstamps->hwtstamp &&
2696 	     (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2697 		__sock_recv_timestamp(msg, sk, skb);
2698 	else
2699 		sock_write_timestamp(sk, kt);
2700 
2701 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2702 		__sock_recv_wifi_status(msg, sk, skb);
2703 }
2704 
2705 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2706 		       struct sk_buff *skb);
2707 
2708 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_cmsgs(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2709 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2710 				   struct sk_buff *skb)
2711 {
2712 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2713 			   (1UL << SOCK_RCVTSTAMP)			| \
2714 			   (1UL << SOCK_RCVMARK)			| \
2715 			   (1UL << SOCK_RCVPRIORITY)			| \
2716 			   (1UL << SOCK_TIMESTAMPING_ANY))
2717 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2718 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2719 
2720 	if (READ_ONCE(sk->sk_flags) & FLAGS_RECV_CMSGS)
2721 		__sock_recv_cmsgs(msg, sk, skb);
2722 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2723 		sock_write_timestamp(sk, skb->tstamp);
2724 	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2725 		sock_write_timestamp(sk, 0);
2726 }
2727 
2728 void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags);
2729 
2730 /**
2731  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2732  * @sk:		socket sending this packet
2733  * @sockc:	pointer to socket cmsg cookie to get timestamping info
2734  * @tx_flags:	completed with instructions for time stamping
2735  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2736  *
2737  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2738  */
_sock_tx_timestamp(struct sock * sk,const struct sockcm_cookie * sockc,__u8 * tx_flags,__u32 * tskey)2739 static inline void _sock_tx_timestamp(struct sock *sk,
2740 				      const struct sockcm_cookie *sockc,
2741 				      __u8 *tx_flags, __u32 *tskey)
2742 {
2743 	__u32 tsflags = sockc->tsflags;
2744 
2745 	if (unlikely(tsflags)) {
2746 		__sock_tx_timestamp(tsflags, tx_flags);
2747 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2748 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) {
2749 			if (tsflags & SOCKCM_FLAG_TS_OPT_ID)
2750 				*tskey = sockc->ts_opt_id;
2751 			else
2752 				*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2753 		}
2754 	}
2755 }
2756 
sock_tx_timestamp(struct sock * sk,const struct sockcm_cookie * sockc,__u8 * tx_flags)2757 static inline void sock_tx_timestamp(struct sock *sk,
2758 				     const struct sockcm_cookie *sockc,
2759 				     __u8 *tx_flags)
2760 {
2761 	_sock_tx_timestamp(sk, sockc, tx_flags, NULL);
2762 }
2763 
skb_setup_tx_timestamp(struct sk_buff * skb,const struct sockcm_cookie * sockc)2764 static inline void skb_setup_tx_timestamp(struct sk_buff *skb,
2765 					  const struct sockcm_cookie *sockc)
2766 {
2767 	_sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags,
2768 			   &skb_shinfo(skb)->tskey);
2769 }
2770 
sk_is_inet(const struct sock * sk)2771 static inline bool sk_is_inet(const struct sock *sk)
2772 {
2773 	int family = READ_ONCE(sk->sk_family);
2774 
2775 	return family == AF_INET || family == AF_INET6;
2776 }
2777 
sk_is_tcp(const struct sock * sk)2778 static inline bool sk_is_tcp(const struct sock *sk)
2779 {
2780 	return sk_is_inet(sk) &&
2781 	       sk->sk_type == SOCK_STREAM &&
2782 	       sk->sk_protocol == IPPROTO_TCP;
2783 }
2784 
sk_is_udp(const struct sock * sk)2785 static inline bool sk_is_udp(const struct sock *sk)
2786 {
2787 	return sk_is_inet(sk) &&
2788 	       sk->sk_type == SOCK_DGRAM &&
2789 	       sk->sk_protocol == IPPROTO_UDP;
2790 }
2791 
sk_is_unix(const struct sock * sk)2792 static inline bool sk_is_unix(const struct sock *sk)
2793 {
2794 	return sk->sk_family == AF_UNIX;
2795 }
2796 
sk_is_stream_unix(const struct sock * sk)2797 static inline bool sk_is_stream_unix(const struct sock *sk)
2798 {
2799 	return sk_is_unix(sk) && sk->sk_type == SOCK_STREAM;
2800 }
2801 
sk_is_vsock(const struct sock * sk)2802 static inline bool sk_is_vsock(const struct sock *sk)
2803 {
2804 	return sk->sk_family == AF_VSOCK;
2805 }
2806 
sk_may_scm_recv(const struct sock * sk)2807 static inline bool sk_may_scm_recv(const struct sock *sk)
2808 {
2809 	return (IS_ENABLED(CONFIG_UNIX) && sk->sk_family == AF_UNIX) ||
2810 		sk->sk_family == AF_NETLINK ||
2811 		(IS_ENABLED(CONFIG_BT) && sk->sk_family == AF_BLUETOOTH);
2812 }
2813 
2814 /**
2815  * sk_eat_skb - Release a skb if it is no longer needed
2816  * @sk: socket to eat this skb from
2817  * @skb: socket buffer to eat
2818  *
2819  * This routine must be called with interrupts disabled or with the socket
2820  * locked so that the sk_buff queue operation is ok.
2821 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2822 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2823 {
2824 	__skb_unlink(skb, &sk->sk_receive_queue);
2825 	__kfree_skb(skb);
2826 }
2827 
2828 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2829 skb_sk_is_prefetched(struct sk_buff *skb)
2830 {
2831 #ifdef CONFIG_INET
2832 	return skb->destructor == sock_pfree;
2833 #else
2834 	return false;
2835 #endif /* CONFIG_INET */
2836 }
2837 
2838 /* This helper checks if a socket is a full socket,
2839  * ie _not_ a timewait or request socket.
2840  */
sk_fullsock(const struct sock * sk)2841 static inline bool sk_fullsock(const struct sock *sk)
2842 {
2843 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2844 }
2845 
2846 static inline bool
sk_is_refcounted(struct sock * sk)2847 sk_is_refcounted(struct sock *sk)
2848 {
2849 	/* Only full sockets have sk->sk_flags. */
2850 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2851 }
2852 
2853 static inline bool
sk_requests_wifi_status(struct sock * sk)2854 sk_requests_wifi_status(struct sock *sk)
2855 {
2856 	return sk && sk_fullsock(sk) && sock_flag(sk, SOCK_WIFI_STATUS);
2857 }
2858 
2859 /* Checks if this SKB belongs to an HW offloaded socket
2860  * and whether any SW fallbacks are required based on dev.
2861  * Check decrypted mark in case skb_orphan() cleared socket.
2862  */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2863 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2864 						   struct net_device *dev)
2865 {
2866 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2867 	struct sock *sk = skb->sk;
2868 
2869 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2870 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2871 	} else if (unlikely(skb_is_decrypted(skb))) {
2872 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2873 		kfree_skb(skb);
2874 		skb = NULL;
2875 	}
2876 #endif
2877 
2878 	return skb;
2879 }
2880 
2881 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2882  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2883  */
sk_listener(const struct sock * sk)2884 static inline bool sk_listener(const struct sock *sk)
2885 {
2886 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2887 }
2888 
2889 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT
2890  * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE)
2891  * TCP RST and ACK can be attached to TIME_WAIT.
2892  */
sk_listener_or_tw(const struct sock * sk)2893 static inline bool sk_listener_or_tw(const struct sock *sk)
2894 {
2895 	return (1 << READ_ONCE(sk->sk_state)) &
2896 	       (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT);
2897 }
2898 
2899 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2900 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2901 		       int type);
2902 
2903 bool sk_ns_capable(const struct sock *sk,
2904 		   struct user_namespace *user_ns, int cap);
2905 bool sk_capable(const struct sock *sk, int cap);
2906 bool sk_net_capable(const struct sock *sk, int cap);
2907 
2908 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2909 
2910 /* Take into consideration the size of the struct sk_buff overhead in the
2911  * determination of these values, since that is non-constant across
2912  * platforms.  This makes socket queueing behavior and performance
2913  * not depend upon such differences.
2914  */
2915 #define _SK_MEM_PACKETS		256
2916 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2917 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2918 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2919 
2920 extern __u32 sysctl_wmem_max;
2921 extern __u32 sysctl_rmem_max;
2922 
2923 extern __u32 sysctl_wmem_default;
2924 extern __u32 sysctl_rmem_default;
2925 
2926 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2927 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2928 
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2929 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2930 {
2931 	/* Does this proto have per netns sysctl_wmem ? */
2932 	if (proto->sysctl_wmem_offset)
2933 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2934 
2935 	return READ_ONCE(*proto->sysctl_wmem);
2936 }
2937 
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2938 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2939 {
2940 	/* Does this proto have per netns sysctl_rmem ? */
2941 	if (proto->sysctl_rmem_offset)
2942 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2943 
2944 	return READ_ONCE(*proto->sysctl_rmem);
2945 }
2946 
2947 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2948  * Some wifi drivers need to tweak it to get more chunks.
2949  * They can use this helper from their ndo_start_xmit()
2950  */
sk_pacing_shift_update(struct sock * sk,int val)2951 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2952 {
2953 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2954 		return;
2955 	WRITE_ONCE(sk->sk_pacing_shift, val);
2956 }
2957 
2958 /* if a socket is bound to a device, check that the given device
2959  * index is either the same or that the socket is bound to an L3
2960  * master device and the given device index is also enslaved to
2961  * that L3 master
2962  */
sk_dev_equal_l3scope(struct sock * sk,int dif)2963 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2964 {
2965 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2966 	int mdif;
2967 
2968 	if (!bound_dev_if || bound_dev_if == dif)
2969 		return true;
2970 
2971 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2972 	if (mdif && mdif == bound_dev_if)
2973 		return true;
2974 
2975 	return false;
2976 }
2977 
2978 void sock_def_readable(struct sock *sk);
2979 
2980 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2981 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2982 int sock_set_timestamping(struct sock *sk, int optname,
2983 			  struct so_timestamping timestamping);
2984 
2985 void sock_enable_timestamps(struct sock *sk);
2986 #if defined(CONFIG_CGROUP_BPF)
2987 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op);
2988 #else
bpf_skops_tx_timestamping(struct sock * sk,struct sk_buff * skb,int op)2989 static inline void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
2990 {
2991 }
2992 #endif
2993 void sock_no_linger(struct sock *sk);
2994 void sock_set_keepalive(struct sock *sk);
2995 void sock_set_priority(struct sock *sk, u32 priority);
2996 void sock_set_rcvbuf(struct sock *sk, int val);
2997 void sock_set_mark(struct sock *sk, u32 val);
2998 void sock_set_reuseaddr(struct sock *sk);
2999 void sock_set_reuseport(struct sock *sk);
3000 void sock_set_sndtimeo(struct sock *sk, s64 secs);
3001 
3002 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
3003 
3004 int sock_get_timeout(long timeo, void *optval, bool old_timeval);
3005 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
3006 			   sockptr_t optval, int optlen, bool old_timeval);
3007 
3008 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
3009 		     void __user *arg, void *karg, size_t size);
3010 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
sk_is_readable(struct sock * sk)3011 static inline bool sk_is_readable(struct sock *sk)
3012 {
3013 	const struct proto *prot = READ_ONCE(sk->sk_prot);
3014 
3015 	if (prot->sock_is_readable)
3016 		return prot->sock_is_readable(sk);
3017 
3018 	return false;
3019 }
3020 #endif	/* _SOCK_H */
3021