xref: /linux/include/net/sock.h (revision d69eb204c255c35abd9e8cb621484e8074c75eaa)
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_ino: inode number (zero if orphaned)
289   *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
290   *	@sk_busy_poll_budget: napi processing budget when busypolling
291   *	@sk_priority: %SO_PRIORITY setting
292   *	@sk_type: socket type (%SOCK_STREAM, etc)
293   *	@sk_protocol: which protocol this socket belongs in this network family
294   *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
295   *	@sk_peer_pid: &struct pid for this socket's peer
296   *	@sk_peer_cred: %SO_PEERCRED setting
297   *	@sk_rcvlowat: %SO_RCVLOWAT setting
298   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
299   *	@sk_sndtimeo: %SO_SNDTIMEO setting
300   *	@sk_txhash: computed flow hash for use on transmit
301   *	@sk_txrehash: enable TX hash rethink
302   *	@sk_filter: socket filtering instructions
303   *	@sk_timer: sock cleanup timer
304   *	@sk_stamp: time stamp of last packet received
305   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
306   *	@sk_tsflags: SO_TIMESTAMPING flags
307   *	@sk_bpf_cb_flags: used in bpf_setsockopt()
308   *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
309   *			   Sockets that can be used under memory reclaim should
310   *			   set this to false.
311   *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
312   *	              for timestamping
313   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
314   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
315   *	@sk_socket: Identd and reporting IO signals
316   *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
317   *	@sk_frag: cached page frag
318   *	@sk_peek_off: current peek_offset value
319   *	@sk_send_head: front of stuff to transmit
320   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
321   *	@sk_security: used by security modules
322   *	@sk_mark: generic packet mark
323   *	@sk_cgrp_data: cgroup data for this cgroup
324   *	@sk_memcg: this socket's memory cgroup association
325   *	@sk_write_pending: a write to stream socket waits to start
326   *	@sk_disconnects: number of disconnect operations performed on this sock
327   *	@sk_state_change: callback to indicate change in the state of the sock
328   *	@sk_data_ready: callback to indicate there is data to be processed
329   *	@sk_write_space: callback to indicate there is bf sending space available
330   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
331   *	@sk_backlog_rcv: callback to process the backlog
332   *	@sk_validate_xmit_skb: ptr to an optional validate function
333   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
334   *	@sk_reuseport_cb: reuseport group container
335   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
336   *	@sk_rcu: used during RCU grace period
337   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
338   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
339   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
340   *	@sk_txtime_unused: unused txtime flags
341   *	@sk_scm_recv_flags: all flags used by scm_recv()
342   *	@sk_scm_credentials: flagged by SO_PASSCRED to recv SCM_CREDENTIALS
343   *	@sk_scm_security: flagged by SO_PASSSEC to recv SCM_SECURITY
344   *	@sk_scm_pidfd: flagged by SO_PASSPIDFD to recv SCM_PIDFD
345   *	@sk_scm_rights: flagged by SO_PASSRIGHTS to recv SCM_RIGHTS
346   *	@sk_scm_unused: unused flags for scm_recv()
347   *	@ns_tracker: tracker for netns reference
348   *	@sk_user_frags: xarray of pages the user is holding a reference on.
349   *	@sk_owner: reference to the real owner of the socket that calls
350   *		   sock_lock_init_class_and_name().
351   */
352 struct sock {
353 	/*
354 	 * Now struct inet_timewait_sock also uses sock_common, so please just
355 	 * don't add nothing before this first member (__sk_common) --acme
356 	 */
357 	struct sock_common	__sk_common;
358 #define sk_node			__sk_common.skc_node
359 #define sk_nulls_node		__sk_common.skc_nulls_node
360 #define sk_refcnt		__sk_common.skc_refcnt
361 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
362 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
363 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
364 #endif
365 
366 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
367 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
368 #define sk_hash			__sk_common.skc_hash
369 #define sk_portpair		__sk_common.skc_portpair
370 #define sk_num			__sk_common.skc_num
371 #define sk_dport		__sk_common.skc_dport
372 #define sk_addrpair		__sk_common.skc_addrpair
373 #define sk_daddr		__sk_common.skc_daddr
374 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
375 #define sk_family		__sk_common.skc_family
376 #define sk_state		__sk_common.skc_state
377 #define sk_reuse		__sk_common.skc_reuse
378 #define sk_reuseport		__sk_common.skc_reuseport
379 #define sk_ipv6only		__sk_common.skc_ipv6only
380 #define sk_net_refcnt		__sk_common.skc_net_refcnt
381 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
382 #define sk_bind_node		__sk_common.skc_bind_node
383 #define sk_prot			__sk_common.skc_prot
384 #define sk_net			__sk_common.skc_net
385 #define sk_v6_daddr		__sk_common.skc_v6_daddr
386 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
387 #define sk_cookie		__sk_common.skc_cookie
388 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
389 #define sk_flags		__sk_common.skc_flags
390 #define sk_rxhash		__sk_common.skc_rxhash
391 
392 	__cacheline_group_begin(sock_write_rx);
393 
394 	atomic_t		sk_drops;
395 	__s32			sk_peek_off;
396 	struct sk_buff_head	sk_error_queue;
397 	struct sk_buff_head	sk_receive_queue;
398 	/*
399 	 * The backlog queue is special, it is always used with
400 	 * the per-socket spinlock held and requires low latency
401 	 * access. Therefore we special case it's implementation.
402 	 * Note : rmem_alloc is in this structure to fill a hole
403 	 * on 64bit arches, not because its logically part of
404 	 * backlog.
405 	 */
406 	struct {
407 		atomic_t	rmem_alloc;
408 		int		len;
409 		struct sk_buff	*head;
410 		struct sk_buff	*tail;
411 	} sk_backlog;
412 #define sk_rmem_alloc sk_backlog.rmem_alloc
413 
414 	__cacheline_group_end(sock_write_rx);
415 
416 	__cacheline_group_begin(sock_read_rx);
417 	/* early demux fields */
418 	struct dst_entry __rcu	*sk_rx_dst;
419 	int			sk_rx_dst_ifindex;
420 	u32			sk_rx_dst_cookie;
421 
422 #ifdef CONFIG_NET_RX_BUSY_POLL
423 	unsigned int		sk_ll_usec;
424 	unsigned int		sk_napi_id;
425 	u16			sk_busy_poll_budget;
426 	u8			sk_prefer_busy_poll;
427 #endif
428 	u8			sk_userlocks;
429 	int			sk_rcvbuf;
430 
431 	struct sk_filter __rcu	*sk_filter;
432 	union {
433 		struct socket_wq __rcu	*sk_wq;
434 		/* private: */
435 		struct socket_wq	*sk_wq_raw;
436 		/* public: */
437 	};
438 
439 	void			(*sk_data_ready)(struct sock *sk);
440 	long			sk_rcvtimeo;
441 	int			sk_rcvlowat;
442 	__cacheline_group_end(sock_read_rx);
443 
444 	__cacheline_group_begin(sock_read_rxtx);
445 	int			sk_err;
446 	struct socket		*sk_socket;
447 	struct mem_cgroup	*sk_memcg;
448 #ifdef CONFIG_XFRM
449 	struct xfrm_policy __rcu *sk_policy[2];
450 #endif
451 	__cacheline_group_end(sock_read_rxtx);
452 
453 	__cacheline_group_begin(sock_write_rxtx);
454 	socket_lock_t		sk_lock;
455 	u32			sk_reserved_mem;
456 	int			sk_forward_alloc;
457 	u32			sk_tsflags;
458 	__cacheline_group_end(sock_write_rxtx);
459 
460 	__cacheline_group_begin(sock_write_tx);
461 	int			sk_write_pending;
462 	atomic_t		sk_omem_alloc;
463 	int			sk_sndbuf;
464 
465 	int			sk_wmem_queued;
466 	refcount_t		sk_wmem_alloc;
467 	unsigned long		sk_tsq_flags;
468 	union {
469 		struct sk_buff	*sk_send_head;
470 		struct rb_root	tcp_rtx_queue;
471 	};
472 	struct sk_buff_head	sk_write_queue;
473 	u32			sk_dst_pending_confirm;
474 	u32			sk_pacing_status; /* see enum sk_pacing */
475 	struct page_frag	sk_frag;
476 	struct timer_list	sk_timer;
477 
478 	unsigned long		sk_pacing_rate; /* bytes per second */
479 	atomic_t		sk_zckey;
480 	atomic_t		sk_tskey;
481 	__cacheline_group_end(sock_write_tx);
482 
483 	__cacheline_group_begin(sock_read_tx);
484 	unsigned long		sk_max_pacing_rate;
485 	long			sk_sndtimeo;
486 	u32			sk_priority;
487 	u32			sk_mark;
488 	struct dst_entry __rcu	*sk_dst_cache;
489 	netdev_features_t	sk_route_caps;
490 #ifdef CONFIG_SOCK_VALIDATE_XMIT
491 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
492 							struct net_device *dev,
493 							struct sk_buff *skb);
494 #endif
495 	u16			sk_gso_type;
496 	u16			sk_gso_max_segs;
497 	unsigned int		sk_gso_max_size;
498 	gfp_t			sk_allocation;
499 	u32			sk_txhash;
500 	u8			sk_pacing_shift;
501 	bool			sk_use_task_frag;
502 	__cacheline_group_end(sock_read_tx);
503 
504 	/*
505 	 * Because of non atomicity rules, all
506 	 * changes are protected by socket lock.
507 	 */
508 	u8			sk_gso_disabled : 1,
509 				sk_kern_sock : 1,
510 				sk_no_check_tx : 1,
511 				sk_no_check_rx : 1;
512 	u8			sk_shutdown;
513 	u16			sk_type;
514 	u16			sk_protocol;
515 	unsigned long	        sk_lingertime;
516 	struct proto		*sk_prot_creator;
517 	rwlock_t		sk_callback_lock;
518 	int			sk_err_soft;
519 	u32			sk_ack_backlog;
520 	u32			sk_max_ack_backlog;
521 	kuid_t			sk_uid;
522 	unsigned long		sk_ino;
523 	spinlock_t		sk_peer_lock;
524 	int			sk_bind_phc;
525 	struct pid		*sk_peer_pid;
526 	const struct cred	*sk_peer_cred;
527 
528 	ktime_t			sk_stamp;
529 #if BITS_PER_LONG==32
530 	seqlock_t		sk_stamp_seq;
531 #endif
532 	int			sk_disconnects;
533 
534 	union {
535 		u8		sk_txrehash;
536 		u8		sk_scm_recv_flags;
537 		struct {
538 			u8	sk_scm_credentials : 1,
539 				sk_scm_security : 1,
540 				sk_scm_pidfd : 1,
541 				sk_scm_rights : 1,
542 				sk_scm_unused : 4;
543 		};
544 	};
545 	u8			sk_clockid;
546 	u8			sk_txtime_deadline_mode : 1,
547 				sk_txtime_report_errors : 1,
548 				sk_txtime_unused : 6;
549 #define SK_BPF_CB_FLAG_TEST(SK, FLAG) ((SK)->sk_bpf_cb_flags & (FLAG))
550 	u8			sk_bpf_cb_flags;
551 
552 	void			*sk_user_data;
553 #ifdef CONFIG_SECURITY
554 	void			*sk_security;
555 #endif
556 	struct sock_cgroup_data	sk_cgrp_data;
557 	void			(*sk_state_change)(struct sock *sk);
558 	void			(*sk_write_space)(struct sock *sk);
559 	void			(*sk_error_report)(struct sock *sk);
560 	int			(*sk_backlog_rcv)(struct sock *sk,
561 						  struct sk_buff *skb);
562 	void                    (*sk_destruct)(struct sock *sk);
563 	struct sock_reuseport __rcu	*sk_reuseport_cb;
564 #ifdef CONFIG_BPF_SYSCALL
565 	struct bpf_local_storage __rcu	*sk_bpf_storage;
566 #endif
567 	struct rcu_head		sk_rcu;
568 	netns_tracker		ns_tracker;
569 	struct xarray		sk_user_frags;
570 
571 #if IS_ENABLED(CONFIG_PROVE_LOCKING) && IS_ENABLED(CONFIG_MODULES)
572 	struct module		*sk_owner;
573 #endif
574 };
575 
576 struct sock_bh_locked {
577 	struct sock *sock;
578 	local_lock_t bh_lock;
579 };
580 
581 enum sk_pacing {
582 	SK_PACING_NONE		= 0,
583 	SK_PACING_NEEDED	= 1,
584 	SK_PACING_FQ		= 2,
585 };
586 
587 /* flag bits in sk_user_data
588  *
589  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
590  *   not be suitable for copying when cloning the socket. For instance,
591  *   it can point to a reference counted object. sk_user_data bottom
592  *   bit is set if pointer must not be copied.
593  *
594  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
595  *   managed/owned by a BPF reuseport array. This bit should be set
596  *   when sk_user_data's sk is added to the bpf's reuseport_array.
597  *
598  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
599  *   sk_user_data points to psock type. This bit should be set
600  *   when sk_user_data is assigned to a psock object.
601  */
602 #define SK_USER_DATA_NOCOPY	1UL
603 #define SK_USER_DATA_BPF	2UL
604 #define SK_USER_DATA_PSOCK	4UL
605 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
606 				  SK_USER_DATA_PSOCK)
607 
608 /**
609  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
610  * @sk: socket
611  */
sk_user_data_is_nocopy(const struct sock * sk)612 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
613 {
614 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
615 }
616 
617 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
618 
619 /**
620  * __locked_read_sk_user_data_with_flags - return the pointer
621  * only if argument flags all has been set in sk_user_data. Otherwise
622  * return NULL
623  *
624  * @sk: socket
625  * @flags: flag bits
626  *
627  * The caller must be holding sk->sk_callback_lock.
628  */
629 static inline void *
__locked_read_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)630 __locked_read_sk_user_data_with_flags(const struct sock *sk,
631 				      uintptr_t flags)
632 {
633 	uintptr_t sk_user_data =
634 		(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
635 						 lockdep_is_held(&sk->sk_callback_lock));
636 
637 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
638 
639 	if ((sk_user_data & flags) == flags)
640 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
641 	return NULL;
642 }
643 
644 /**
645  * __rcu_dereference_sk_user_data_with_flags - return the pointer
646  * only if argument flags all has been set in sk_user_data. Otherwise
647  * return NULL
648  *
649  * @sk: socket
650  * @flags: flag bits
651  */
652 static inline void *
__rcu_dereference_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)653 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
654 					  uintptr_t flags)
655 {
656 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
657 
658 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
659 
660 	if ((sk_user_data & flags) == flags)
661 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
662 	return NULL;
663 }
664 
665 #define rcu_dereference_sk_user_data(sk)				\
666 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
667 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
668 ({									\
669 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
670 		  __tmp2 = (uintptr_t)(flags);				\
671 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
672 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
673 	rcu_assign_pointer(__sk_user_data((sk)),			\
674 			   __tmp1 | __tmp2);				\
675 })
676 #define rcu_assign_sk_user_data(sk, ptr)				\
677 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
678 
679 static inline
sock_net(const struct sock * sk)680 struct net *sock_net(const struct sock *sk)
681 {
682 	return read_pnet(&sk->sk_net);
683 }
684 
685 static inline
sock_net_set(struct sock * sk,struct net * net)686 void sock_net_set(struct sock *sk, struct net *net)
687 {
688 	write_pnet(&sk->sk_net, net);
689 }
690 
691 /*
692  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
693  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
694  * on a socket means that the socket will reuse everybody else's port
695  * without looking at the other's sk_reuse value.
696  */
697 
698 #define SK_NO_REUSE	0
699 #define SK_CAN_REUSE	1
700 #define SK_FORCE_REUSE	2
701 
702 int sk_set_peek_off(struct sock *sk, int val);
703 
sk_peek_offset(const struct sock * sk,int flags)704 static inline int sk_peek_offset(const struct sock *sk, int flags)
705 {
706 	if (unlikely(flags & MSG_PEEK)) {
707 		return READ_ONCE(sk->sk_peek_off);
708 	}
709 
710 	return 0;
711 }
712 
sk_peek_offset_bwd(struct sock * sk,int val)713 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
714 {
715 	s32 off = READ_ONCE(sk->sk_peek_off);
716 
717 	if (unlikely(off >= 0)) {
718 		off = max_t(s32, off - val, 0);
719 		WRITE_ONCE(sk->sk_peek_off, off);
720 	}
721 }
722 
sk_peek_offset_fwd(struct sock * sk,int val)723 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
724 {
725 	sk_peek_offset_bwd(sk, -val);
726 }
727 
728 /*
729  * Hashed lists helper routines
730  */
sk_entry(const struct hlist_node * node)731 static inline struct sock *sk_entry(const struct hlist_node *node)
732 {
733 	return hlist_entry(node, struct sock, sk_node);
734 }
735 
__sk_head(const struct hlist_head * head)736 static inline struct sock *__sk_head(const struct hlist_head *head)
737 {
738 	return hlist_entry(head->first, struct sock, sk_node);
739 }
740 
sk_head(const struct hlist_head * head)741 static inline struct sock *sk_head(const struct hlist_head *head)
742 {
743 	return hlist_empty(head) ? NULL : __sk_head(head);
744 }
745 
__sk_nulls_head(const struct hlist_nulls_head * head)746 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
747 {
748 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
749 }
750 
sk_nulls_head(const struct hlist_nulls_head * head)751 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
752 {
753 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
754 }
755 
sk_next(const struct sock * sk)756 static inline struct sock *sk_next(const struct sock *sk)
757 {
758 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
759 }
760 
sk_nulls_next(const struct sock * sk)761 static inline struct sock *sk_nulls_next(const struct sock *sk)
762 {
763 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
764 		hlist_nulls_entry(sk->sk_nulls_node.next,
765 				  struct sock, sk_nulls_node) :
766 		NULL;
767 }
768 
sk_unhashed(const struct sock * sk)769 static inline bool sk_unhashed(const struct sock *sk)
770 {
771 	return hlist_unhashed(&sk->sk_node);
772 }
773 
sk_hashed(const struct sock * sk)774 static inline bool sk_hashed(const struct sock *sk)
775 {
776 	return !sk_unhashed(sk);
777 }
778 
sk_node_init(struct hlist_node * node)779 static inline void sk_node_init(struct hlist_node *node)
780 {
781 	node->pprev = NULL;
782 }
783 
__sk_del_node(struct sock * sk)784 static inline void __sk_del_node(struct sock *sk)
785 {
786 	__hlist_del(&sk->sk_node);
787 }
788 
789 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)790 static inline bool __sk_del_node_init(struct sock *sk)
791 {
792 	if (sk_hashed(sk)) {
793 		__sk_del_node(sk);
794 		sk_node_init(&sk->sk_node);
795 		return true;
796 	}
797 	return false;
798 }
799 
800 /* Grab socket reference count. This operation is valid only
801    when sk is ALREADY grabbed f.e. it is found in hash table
802    or a list and the lookup is made under lock preventing hash table
803    modifications.
804  */
805 
sock_hold(struct sock * sk)806 static __always_inline void sock_hold(struct sock *sk)
807 {
808 	refcount_inc(&sk->sk_refcnt);
809 }
810 
811 /* Ungrab socket in the context, which assumes that socket refcnt
812    cannot hit zero, f.e. it is true in context of any socketcall.
813  */
__sock_put(struct sock * sk)814 static __always_inline void __sock_put(struct sock *sk)
815 {
816 	refcount_dec(&sk->sk_refcnt);
817 }
818 
sk_del_node_init(struct sock * sk)819 static inline bool sk_del_node_init(struct sock *sk)
820 {
821 	bool rc = __sk_del_node_init(sk);
822 
823 	if (rc) {
824 		/* paranoid for a while -acme */
825 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
826 		__sock_put(sk);
827 	}
828 	return rc;
829 }
830 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
831 
__sk_nulls_del_node_init_rcu(struct sock * sk)832 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
833 {
834 	if (sk_hashed(sk)) {
835 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
836 		return true;
837 	}
838 	return false;
839 }
840 
sk_nulls_del_node_init_rcu(struct sock * sk)841 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
842 {
843 	bool rc = __sk_nulls_del_node_init_rcu(sk);
844 
845 	if (rc) {
846 		/* paranoid for a while -acme */
847 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
848 		__sock_put(sk);
849 	}
850 	return rc;
851 }
852 
__sk_add_node(struct sock * sk,struct hlist_head * list)853 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
854 {
855 	hlist_add_head(&sk->sk_node, list);
856 }
857 
sk_add_node(struct sock * sk,struct hlist_head * list)858 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
859 {
860 	sock_hold(sk);
861 	__sk_add_node(sk, list);
862 }
863 
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)864 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
865 {
866 	sock_hold(sk);
867 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
868 	    sk->sk_family == AF_INET6)
869 		hlist_add_tail_rcu(&sk->sk_node, list);
870 	else
871 		hlist_add_head_rcu(&sk->sk_node, list);
872 }
873 
sk_add_node_tail_rcu(struct sock * sk,struct hlist_head * list)874 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
875 {
876 	sock_hold(sk);
877 	hlist_add_tail_rcu(&sk->sk_node, list);
878 }
879 
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)880 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
881 {
882 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
883 }
884 
__sk_nulls_add_node_tail_rcu(struct sock * sk,struct hlist_nulls_head * list)885 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
886 {
887 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
888 }
889 
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)890 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
891 {
892 	sock_hold(sk);
893 	__sk_nulls_add_node_rcu(sk, list);
894 }
895 
__sk_del_bind_node(struct sock * sk)896 static inline void __sk_del_bind_node(struct sock *sk)
897 {
898 	__hlist_del(&sk->sk_bind_node);
899 }
900 
sk_add_bind_node(struct sock * sk,struct hlist_head * list)901 static inline void sk_add_bind_node(struct sock *sk,
902 					struct hlist_head *list)
903 {
904 	hlist_add_head(&sk->sk_bind_node, list);
905 }
906 
907 #define sk_for_each(__sk, list) \
908 	hlist_for_each_entry(__sk, list, sk_node)
909 #define sk_for_each_rcu(__sk, list) \
910 	hlist_for_each_entry_rcu(__sk, list, sk_node)
911 #define sk_nulls_for_each(__sk, node, list) \
912 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
913 #define sk_nulls_for_each_rcu(__sk, node, list) \
914 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
915 #define sk_for_each_from(__sk) \
916 	hlist_for_each_entry_from(__sk, sk_node)
917 #define sk_nulls_for_each_from(__sk, node) \
918 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
919 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
920 #define sk_for_each_safe(__sk, tmp, list) \
921 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
922 #define sk_for_each_bound(__sk, list) \
923 	hlist_for_each_entry(__sk, list, sk_bind_node)
924 #define sk_for_each_bound_safe(__sk, tmp, list) \
925 	hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node)
926 
927 /**
928  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
929  * @tpos:	the type * to use as a loop cursor.
930  * @pos:	the &struct hlist_node to use as a loop cursor.
931  * @head:	the head for your list.
932  * @offset:	offset of hlist_node within the struct.
933  *
934  */
935 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
936 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
937 	     pos != NULL &&						       \
938 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
939 	     pos = rcu_dereference(hlist_next_rcu(pos)))
940 
sk_user_ns(const struct sock * sk)941 static inline struct user_namespace *sk_user_ns(const struct sock *sk)
942 {
943 	/* Careful only use this in a context where these parameters
944 	 * can not change and must all be valid, such as recvmsg from
945 	 * userspace.
946 	 */
947 	return sk->sk_socket->file->f_cred->user_ns;
948 }
949 
950 /* Sock flags */
951 enum sock_flags {
952 	SOCK_DEAD,
953 	SOCK_DONE,
954 	SOCK_URGINLINE,
955 	SOCK_KEEPOPEN,
956 	SOCK_LINGER,
957 	SOCK_DESTROY,
958 	SOCK_BROADCAST,
959 	SOCK_TIMESTAMP,
960 	SOCK_ZAPPED,
961 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
962 	SOCK_DBG, /* %SO_DEBUG setting */
963 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
964 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
965 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
966 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
967 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
968 	SOCK_FASYNC, /* fasync() active */
969 	SOCK_RXQ_OVFL,
970 	SOCK_ZEROCOPY, /* buffers from userspace */
971 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
972 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
973 		     * Will use last 4 bytes of packet sent from
974 		     * user-space instead.
975 		     */
976 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
977 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
978 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
979 	SOCK_TXTIME,
980 	SOCK_XDP, /* XDP is attached */
981 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
982 	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
983 	SOCK_RCVPRIORITY, /* Receive SO_PRIORITY ancillary data with packet */
984 	SOCK_TIMESTAMPING_ANY, /* Copy of sk_tsflags & TSFLAGS_ANY */
985 };
986 
987 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
988 /*
989  * The highest bit of sk_tsflags is reserved for kernel-internal
990  * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that
991  * SOF_TIMESTAMPING* values do not reach this reserved area
992  */
993 #define SOCKCM_FLAG_TS_OPT_ID	BIT(31)
994 
sock_copy_flags(struct sock * nsk,const struct sock * osk)995 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
996 {
997 	nsk->sk_flags = osk->sk_flags;
998 }
999 
sock_set_flag(struct sock * sk,enum sock_flags flag)1000 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
1001 {
1002 	__set_bit(flag, &sk->sk_flags);
1003 }
1004 
sock_reset_flag(struct sock * sk,enum sock_flags flag)1005 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
1006 {
1007 	__clear_bit(flag, &sk->sk_flags);
1008 }
1009 
sock_valbool_flag(struct sock * sk,enum sock_flags bit,int valbool)1010 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
1011 				     int valbool)
1012 {
1013 	if (valbool)
1014 		sock_set_flag(sk, bit);
1015 	else
1016 		sock_reset_flag(sk, bit);
1017 }
1018 
sock_flag(const struct sock * sk,enum sock_flags flag)1019 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
1020 {
1021 	return test_bit(flag, &sk->sk_flags);
1022 }
1023 
1024 #ifdef CONFIG_NET
1025 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
sk_memalloc_socks(void)1026 static inline int sk_memalloc_socks(void)
1027 {
1028 	return static_branch_unlikely(&memalloc_socks_key);
1029 }
1030 
1031 void __receive_sock(struct file *file);
1032 #else
1033 
sk_memalloc_socks(void)1034 static inline int sk_memalloc_socks(void)
1035 {
1036 	return 0;
1037 }
1038 
__receive_sock(struct file * file)1039 static inline void __receive_sock(struct file *file)
1040 { }
1041 #endif
1042 
sk_gfp_mask(const struct sock * sk,gfp_t gfp_mask)1043 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1044 {
1045 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1046 }
1047 
sk_acceptq_removed(struct sock * sk)1048 static inline void sk_acceptq_removed(struct sock *sk)
1049 {
1050 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1051 }
1052 
sk_acceptq_added(struct sock * sk)1053 static inline void sk_acceptq_added(struct sock *sk)
1054 {
1055 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1056 }
1057 
1058 /* Note: If you think the test should be:
1059  *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1060  * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1061  */
sk_acceptq_is_full(const struct sock * sk)1062 static inline bool sk_acceptq_is_full(const struct sock *sk)
1063 {
1064 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1065 }
1066 
1067 /*
1068  * Compute minimal free write space needed to queue new packets.
1069  */
sk_stream_min_wspace(const struct sock * sk)1070 static inline int sk_stream_min_wspace(const struct sock *sk)
1071 {
1072 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1073 }
1074 
sk_stream_wspace(const struct sock * sk)1075 static inline int sk_stream_wspace(const struct sock *sk)
1076 {
1077 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1078 }
1079 
sk_wmem_queued_add(struct sock * sk,int val)1080 static inline void sk_wmem_queued_add(struct sock *sk, int val)
1081 {
1082 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1083 }
1084 
sk_forward_alloc_add(struct sock * sk,int val)1085 static inline void sk_forward_alloc_add(struct sock *sk, int val)
1086 {
1087 	/* Paired with lockless reads of sk->sk_forward_alloc */
1088 	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1089 }
1090 
1091 void sk_stream_write_space(struct sock *sk);
1092 
1093 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)1094 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1095 {
1096 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1097 	skb_dst_force(skb);
1098 
1099 	if (!sk->sk_backlog.tail)
1100 		WRITE_ONCE(sk->sk_backlog.head, skb);
1101 	else
1102 		sk->sk_backlog.tail->next = skb;
1103 
1104 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1105 	skb->next = NULL;
1106 }
1107 
1108 /*
1109  * Take into account size of receive queue and backlog queue
1110  * Do not take into account this skb truesize,
1111  * to allow even a single big packet to come.
1112  */
sk_rcvqueues_full(const struct sock * sk,unsigned int limit)1113 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1114 {
1115 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1116 
1117 	return qsize > limit;
1118 }
1119 
1120 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb,unsigned int limit)1121 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1122 					      unsigned int limit)
1123 {
1124 	if (sk_rcvqueues_full(sk, limit))
1125 		return -ENOBUFS;
1126 
1127 	/*
1128 	 * If the skb was allocated from pfmemalloc reserves, only
1129 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1130 	 * helping free memory
1131 	 */
1132 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1133 		return -ENOMEM;
1134 
1135 	__sk_add_backlog(sk, skb);
1136 	sk->sk_backlog.len += skb->truesize;
1137 	return 0;
1138 }
1139 
1140 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1141 
1142 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1143 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1144 
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1145 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1146 {
1147 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1148 		return __sk_backlog_rcv(sk, skb);
1149 
1150 	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1151 				  tcp_v6_do_rcv,
1152 				  tcp_v4_do_rcv,
1153 				  sk, skb);
1154 }
1155 
sk_incoming_cpu_update(struct sock * sk)1156 static inline void sk_incoming_cpu_update(struct sock *sk)
1157 {
1158 	int cpu = raw_smp_processor_id();
1159 
1160 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1161 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1162 }
1163 
1164 
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1165 static inline void sock_rps_save_rxhash(struct sock *sk,
1166 					const struct sk_buff *skb)
1167 {
1168 #ifdef CONFIG_RPS
1169 	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1170 	 * here, and another one in sock_rps_record_flow().
1171 	 */
1172 	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1173 		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1174 #endif
1175 }
1176 
sock_rps_reset_rxhash(struct sock * sk)1177 static inline void sock_rps_reset_rxhash(struct sock *sk)
1178 {
1179 #ifdef CONFIG_RPS
1180 	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1181 	WRITE_ONCE(sk->sk_rxhash, 0);
1182 #endif
1183 }
1184 
1185 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1186 	({	int __rc, __dis = __sk->sk_disconnects;			\
1187 		release_sock(__sk);					\
1188 		__rc = __condition;					\
1189 		if (!__rc) {						\
1190 			*(__timeo) = wait_woken(__wait,			\
1191 						TASK_INTERRUPTIBLE,	\
1192 						*(__timeo));		\
1193 		}							\
1194 		sched_annotate_sleep();					\
1195 		lock_sock(__sk);					\
1196 		__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1197 		__rc;							\
1198 	})
1199 
1200 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1201 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1202 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1203 int sk_stream_error(struct sock *sk, int flags, int err);
1204 void sk_stream_kill_queues(struct sock *sk);
1205 void sk_set_memalloc(struct sock *sk);
1206 void sk_clear_memalloc(struct sock *sk);
1207 
1208 void __sk_flush_backlog(struct sock *sk);
1209 
sk_flush_backlog(struct sock * sk)1210 static inline bool sk_flush_backlog(struct sock *sk)
1211 {
1212 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1213 		__sk_flush_backlog(sk);
1214 		return true;
1215 	}
1216 	return false;
1217 }
1218 
1219 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1220 
1221 struct request_sock_ops;
1222 struct timewait_sock_ops;
1223 struct inet_hashinfo;
1224 struct raw_hashinfo;
1225 struct smc_hashinfo;
1226 struct module;
1227 struct sk_psock;
1228 
1229 /*
1230  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1231  * un-modified. Special care is taken when initializing object to zero.
1232  */
sk_prot_clear_nulls(struct sock * sk,int size)1233 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1234 {
1235 	if (offsetof(struct sock, sk_node.next) != 0)
1236 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1237 	memset(&sk->sk_node.pprev, 0,
1238 	       size - offsetof(struct sock, sk_node.pprev));
1239 }
1240 
1241 struct proto_accept_arg {
1242 	int flags;
1243 	int err;
1244 	int is_empty;
1245 	bool kern;
1246 };
1247 
1248 /* Networking protocol blocks we attach to sockets.
1249  * socket layer -> transport layer interface
1250  */
1251 struct proto {
1252 	void			(*close)(struct sock *sk,
1253 					long timeout);
1254 	int			(*pre_connect)(struct sock *sk,
1255 					struct sockaddr *uaddr,
1256 					int addr_len);
1257 	int			(*connect)(struct sock *sk,
1258 					struct sockaddr *uaddr,
1259 					int addr_len);
1260 	int			(*disconnect)(struct sock *sk, int flags);
1261 
1262 	struct sock *		(*accept)(struct sock *sk,
1263 					  struct proto_accept_arg *arg);
1264 
1265 	int			(*ioctl)(struct sock *sk, int cmd,
1266 					 int *karg);
1267 	int			(*init)(struct sock *sk);
1268 	void			(*destroy)(struct sock *sk);
1269 	void			(*shutdown)(struct sock *sk, int how);
1270 	int			(*setsockopt)(struct sock *sk, int level,
1271 					int optname, sockptr_t optval,
1272 					unsigned int optlen);
1273 	int			(*getsockopt)(struct sock *sk, int level,
1274 					int optname, char __user *optval,
1275 					int __user *option);
1276 	void			(*keepalive)(struct sock *sk, int valbool);
1277 #ifdef CONFIG_COMPAT
1278 	int			(*compat_ioctl)(struct sock *sk,
1279 					unsigned int cmd, unsigned long arg);
1280 #endif
1281 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1282 					   size_t len);
1283 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1284 					   size_t len, int flags, int *addr_len);
1285 	void			(*splice_eof)(struct socket *sock);
1286 	int			(*bind)(struct sock *sk,
1287 					struct sockaddr *addr, int addr_len);
1288 	int			(*bind_add)(struct sock *sk,
1289 					struct sockaddr *addr, int addr_len);
1290 
1291 	int			(*backlog_rcv) (struct sock *sk,
1292 						struct sk_buff *skb);
1293 	bool			(*bpf_bypass_getsockopt)(int level,
1294 							 int optname);
1295 
1296 	void		(*release_cb)(struct sock *sk);
1297 
1298 	/* Keeping track of sk's, looking them up, and port selection methods. */
1299 	int			(*hash)(struct sock *sk);
1300 	void			(*unhash)(struct sock *sk);
1301 	void			(*rehash)(struct sock *sk);
1302 	int			(*get_port)(struct sock *sk, unsigned short snum);
1303 	void			(*put_port)(struct sock *sk);
1304 #ifdef CONFIG_BPF_SYSCALL
1305 	int			(*psock_update_sk_prot)(struct sock *sk,
1306 							struct sk_psock *psock,
1307 							bool restore);
1308 #endif
1309 
1310 	/* Keeping track of sockets in use */
1311 #ifdef CONFIG_PROC_FS
1312 	unsigned int		inuse_idx;
1313 #endif
1314 
1315 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1316 	bool			(*sock_is_readable)(struct sock *sk);
1317 	/* Memory pressure */
1318 	void			(*enter_memory_pressure)(struct sock *sk);
1319 	void			(*leave_memory_pressure)(struct sock *sk);
1320 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1321 	int  __percpu		*per_cpu_fw_alloc;
1322 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1323 
1324 	/*
1325 	 * Pressure flag: try to collapse.
1326 	 * Technical note: it is used by multiple contexts non atomically.
1327 	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1328 	 * All the __sk_mem_schedule() is of this nature: accounting
1329 	 * is strict, actions are advisory and have some latency.
1330 	 */
1331 	unsigned long		*memory_pressure;
1332 	long			*sysctl_mem;
1333 
1334 	int			*sysctl_wmem;
1335 	int			*sysctl_rmem;
1336 	u32			sysctl_wmem_offset;
1337 	u32			sysctl_rmem_offset;
1338 
1339 	int			max_header;
1340 	bool			no_autobind;
1341 
1342 	struct kmem_cache	*slab;
1343 	unsigned int		obj_size;
1344 	unsigned int		ipv6_pinfo_offset;
1345 	slab_flags_t		slab_flags;
1346 	unsigned int		useroffset;	/* Usercopy region offset */
1347 	unsigned int		usersize;	/* Usercopy region size */
1348 
1349 	unsigned int __percpu	*orphan_count;
1350 
1351 	struct request_sock_ops	*rsk_prot;
1352 	struct timewait_sock_ops *twsk_prot;
1353 
1354 	union {
1355 		struct inet_hashinfo	*hashinfo;
1356 		struct udp_table	*udp_table;
1357 		struct raw_hashinfo	*raw_hash;
1358 		struct smc_hashinfo	*smc_hash;
1359 	} h;
1360 
1361 	struct module		*owner;
1362 
1363 	char			name[32];
1364 
1365 	struct list_head	node;
1366 	int			(*diag_destroy)(struct sock *sk, int err);
1367 } __randomize_layout;
1368 
1369 int proto_register(struct proto *prot, int alloc_slab);
1370 void proto_unregister(struct proto *prot);
1371 int sock_load_diag_module(int family, int protocol);
1372 
1373 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1374 
__sk_stream_memory_free(const struct sock * sk,int wake)1375 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1376 {
1377 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1378 		return false;
1379 
1380 	return sk->sk_prot->stream_memory_free ?
1381 		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1382 				     tcp_stream_memory_free, sk, wake) : true;
1383 }
1384 
sk_stream_memory_free(const struct sock * sk)1385 static inline bool sk_stream_memory_free(const struct sock *sk)
1386 {
1387 	return __sk_stream_memory_free(sk, 0);
1388 }
1389 
__sk_stream_is_writeable(const struct sock * sk,int wake)1390 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1391 {
1392 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1393 	       __sk_stream_memory_free(sk, wake);
1394 }
1395 
sk_stream_is_writeable(const struct sock * sk)1396 static inline bool sk_stream_is_writeable(const struct sock *sk)
1397 {
1398 	return __sk_stream_is_writeable(sk, 0);
1399 }
1400 
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1401 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1402 					    struct cgroup *ancestor)
1403 {
1404 #ifdef CONFIG_SOCK_CGROUP_DATA
1405 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1406 				    ancestor);
1407 #else
1408 	return -ENOTSUPP;
1409 #endif
1410 }
1411 
1412 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1413 
sk_sockets_allocated_dec(struct sock * sk)1414 static inline void sk_sockets_allocated_dec(struct sock *sk)
1415 {
1416 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1417 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1418 }
1419 
sk_sockets_allocated_inc(struct sock * sk)1420 static inline void sk_sockets_allocated_inc(struct sock *sk)
1421 {
1422 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1423 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1424 }
1425 
1426 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1427 sk_sockets_allocated_read_positive(struct sock *sk)
1428 {
1429 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1430 }
1431 
1432 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1433 proto_sockets_allocated_sum_positive(struct proto *prot)
1434 {
1435 	return percpu_counter_sum_positive(prot->sockets_allocated);
1436 }
1437 
1438 #ifdef CONFIG_PROC_FS
1439 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
1440 struct prot_inuse {
1441 	int all;
1442 	int val[PROTO_INUSE_NR];
1443 };
1444 
sock_prot_inuse_add(const struct net * net,const struct proto * prot,int val)1445 static inline void sock_prot_inuse_add(const struct net *net,
1446 				       const struct proto *prot, int val)
1447 {
1448 	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1449 }
1450 
sock_inuse_add(const struct net * net,int val)1451 static inline void sock_inuse_add(const struct net *net, int val)
1452 {
1453 	this_cpu_add(net->core.prot_inuse->all, val);
1454 }
1455 
1456 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1457 int sock_inuse_get(struct net *net);
1458 #else
sock_prot_inuse_add(const struct net * net,const struct proto * prot,int val)1459 static inline void sock_prot_inuse_add(const struct net *net,
1460 				       const struct proto *prot, int val)
1461 {
1462 }
1463 
sock_inuse_add(const struct net * net,int val)1464 static inline void sock_inuse_add(const struct net *net, int val)
1465 {
1466 }
1467 #endif
1468 
1469 
1470 /* With per-bucket locks this operation is not-atomic, so that
1471  * this version is not worse.
1472  */
__sk_prot_rehash(struct sock * sk)1473 static inline int __sk_prot_rehash(struct sock *sk)
1474 {
1475 	sk->sk_prot->unhash(sk);
1476 	return sk->sk_prot->hash(sk);
1477 }
1478 
1479 /* About 10 seconds */
1480 #define SOCK_DESTROY_TIME (10*HZ)
1481 
1482 /* Sockets 0-1023 can't be bound to unless you are superuser */
1483 #define PROT_SOCK	1024
1484 
1485 #define SHUTDOWN_MASK	3
1486 #define RCV_SHUTDOWN	1
1487 #define SEND_SHUTDOWN	2
1488 
1489 #define SOCK_BINDADDR_LOCK	4
1490 #define SOCK_BINDPORT_LOCK	8
1491 
1492 struct socket_alloc {
1493 	struct socket socket;
1494 	struct inode vfs_inode;
1495 };
1496 
SOCKET_I(struct inode * inode)1497 static inline struct socket *SOCKET_I(struct inode *inode)
1498 {
1499 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1500 }
1501 
SOCK_INODE(struct socket * socket)1502 static inline struct inode *SOCK_INODE(struct socket *socket)
1503 {
1504 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1505 }
1506 
1507 /*
1508  * Functions for memory accounting
1509  */
1510 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1511 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1512 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1513 void __sk_mem_reclaim(struct sock *sk, int amount);
1514 
1515 #define SK_MEM_SEND	0
1516 #define SK_MEM_RECV	1
1517 
1518 /* sysctl_mem values are in pages */
sk_prot_mem_limits(const struct sock * sk,int index)1519 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1520 {
1521 	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1522 }
1523 
sk_mem_pages(int amt)1524 static inline int sk_mem_pages(int amt)
1525 {
1526 	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1527 }
1528 
sk_has_account(struct sock * sk)1529 static inline bool sk_has_account(struct sock *sk)
1530 {
1531 	/* return true if protocol supports memory accounting */
1532 	return !!sk->sk_prot->memory_allocated;
1533 }
1534 
sk_wmem_schedule(struct sock * sk,int size)1535 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1536 {
1537 	int delta;
1538 
1539 	if (!sk_has_account(sk))
1540 		return true;
1541 	delta = size - sk->sk_forward_alloc;
1542 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1543 }
1544 
1545 static inline bool
__sk_rmem_schedule(struct sock * sk,int size,bool pfmemalloc)1546 __sk_rmem_schedule(struct sock *sk, int size, bool pfmemalloc)
1547 {
1548 	int delta;
1549 
1550 	if (!sk_has_account(sk))
1551 		return true;
1552 	delta = size - sk->sk_forward_alloc;
1553 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1554 	       pfmemalloc;
1555 }
1556 
1557 static inline bool
sk_rmem_schedule(struct sock * sk,const struct sk_buff * skb,int size)1558 sk_rmem_schedule(struct sock *sk, const struct sk_buff *skb, int size)
1559 {
1560 	return __sk_rmem_schedule(sk, size, skb_pfmemalloc(skb));
1561 }
1562 
sk_unused_reserved_mem(const struct sock * sk)1563 static inline int sk_unused_reserved_mem(const struct sock *sk)
1564 {
1565 	int unused_mem;
1566 
1567 	if (likely(!sk->sk_reserved_mem))
1568 		return 0;
1569 
1570 	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1571 			atomic_read(&sk->sk_rmem_alloc);
1572 
1573 	return unused_mem > 0 ? unused_mem : 0;
1574 }
1575 
sk_mem_reclaim(struct sock * sk)1576 static inline void sk_mem_reclaim(struct sock *sk)
1577 {
1578 	int reclaimable;
1579 
1580 	if (!sk_has_account(sk))
1581 		return;
1582 
1583 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1584 
1585 	if (reclaimable >= (int)PAGE_SIZE)
1586 		__sk_mem_reclaim(sk, reclaimable);
1587 }
1588 
sk_mem_reclaim_final(struct sock * sk)1589 static inline void sk_mem_reclaim_final(struct sock *sk)
1590 {
1591 	sk->sk_reserved_mem = 0;
1592 	sk_mem_reclaim(sk);
1593 }
1594 
sk_mem_charge(struct sock * sk,int size)1595 static inline void sk_mem_charge(struct sock *sk, int size)
1596 {
1597 	if (!sk_has_account(sk))
1598 		return;
1599 	sk_forward_alloc_add(sk, -size);
1600 }
1601 
sk_mem_uncharge(struct sock * sk,int size)1602 static inline void sk_mem_uncharge(struct sock *sk, int size)
1603 {
1604 	if (!sk_has_account(sk))
1605 		return;
1606 	sk_forward_alloc_add(sk, size);
1607 	sk_mem_reclaim(sk);
1608 }
1609 
1610 #if IS_ENABLED(CONFIG_PROVE_LOCKING) && IS_ENABLED(CONFIG_MODULES)
sk_owner_set(struct sock * sk,struct module * owner)1611 static inline void sk_owner_set(struct sock *sk, struct module *owner)
1612 {
1613 	__module_get(owner);
1614 	sk->sk_owner = owner;
1615 }
1616 
sk_owner_clear(struct sock * sk)1617 static inline void sk_owner_clear(struct sock *sk)
1618 {
1619 	sk->sk_owner = NULL;
1620 }
1621 
sk_owner_put(struct sock * sk)1622 static inline void sk_owner_put(struct sock *sk)
1623 {
1624 	module_put(sk->sk_owner);
1625 }
1626 #else
sk_owner_set(struct sock * sk,struct module * owner)1627 static inline void sk_owner_set(struct sock *sk, struct module *owner)
1628 {
1629 }
1630 
sk_owner_clear(struct sock * sk)1631 static inline void sk_owner_clear(struct sock *sk)
1632 {
1633 }
1634 
sk_owner_put(struct sock * sk)1635 static inline void sk_owner_put(struct sock *sk)
1636 {
1637 }
1638 #endif
1639 /*
1640  * Macro so as to not evaluate some arguments when
1641  * lockdep is not enabled.
1642  *
1643  * Mark both the sk_lock and the sk_lock.slock as a
1644  * per-address-family lock class.
1645  */
1646 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1647 do {									\
1648 	sk_owner_set(sk, THIS_MODULE);					\
1649 	sk->sk_lock.owned = 0;						\
1650 	init_waitqueue_head(&sk->sk_lock.wq);				\
1651 	spin_lock_init(&(sk)->sk_lock.slock);				\
1652 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1653 				   sizeof((sk)->sk_lock));		\
1654 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1655 				   (skey), (sname));			\
1656 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1657 } while (0)
1658 
lockdep_sock_is_held(const struct sock * sk)1659 static inline bool lockdep_sock_is_held(const struct sock *sk)
1660 {
1661 	return lockdep_is_held(&sk->sk_lock) ||
1662 	       lockdep_is_held(&sk->sk_lock.slock);
1663 }
1664 
1665 void lock_sock_nested(struct sock *sk, int subclass);
1666 
lock_sock(struct sock * sk)1667 static inline void lock_sock(struct sock *sk)
1668 {
1669 	lock_sock_nested(sk, 0);
1670 }
1671 
1672 void __lock_sock(struct sock *sk);
1673 void __release_sock(struct sock *sk);
1674 void release_sock(struct sock *sk);
1675 
1676 /* BH context may only use the following locking interface. */
1677 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1678 #define bh_lock_sock_nested(__sk) \
1679 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1680 				SINGLE_DEPTH_NESTING)
1681 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1682 
1683 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1684 
1685 /**
1686  * lock_sock_fast - fast version of lock_sock
1687  * @sk: socket
1688  *
1689  * This version should be used for very small section, where process won't block
1690  * return false if fast path is taken:
1691  *
1692  *   sk_lock.slock locked, owned = 0, BH disabled
1693  *
1694  * return true if slow path is taken:
1695  *
1696  *   sk_lock.slock unlocked, owned = 1, BH enabled
1697  */
lock_sock_fast(struct sock * sk)1698 static inline bool lock_sock_fast(struct sock *sk)
1699 {
1700 	/* The sk_lock has mutex_lock() semantics here. */
1701 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1702 
1703 	return __lock_sock_fast(sk);
1704 }
1705 
1706 /* fast socket lock variant for caller already holding a [different] socket lock */
lock_sock_fast_nested(struct sock * sk)1707 static inline bool lock_sock_fast_nested(struct sock *sk)
1708 {
1709 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1710 
1711 	return __lock_sock_fast(sk);
1712 }
1713 
1714 /**
1715  * unlock_sock_fast - complement of lock_sock_fast
1716  * @sk: socket
1717  * @slow: slow mode
1718  *
1719  * fast unlock socket for user context.
1720  * If slow mode is on, we call regular release_sock()
1721  */
unlock_sock_fast(struct sock * sk,bool slow)1722 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1723 	__releases(&sk->sk_lock.slock)
1724 {
1725 	if (slow) {
1726 		release_sock(sk);
1727 		__release(&sk->sk_lock.slock);
1728 	} else {
1729 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1730 		spin_unlock_bh(&sk->sk_lock.slock);
1731 	}
1732 }
1733 
1734 void sockopt_lock_sock(struct sock *sk);
1735 void sockopt_release_sock(struct sock *sk);
1736 bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1737 bool sockopt_capable(int cap);
1738 
1739 /* Used by processes to "lock" a socket state, so that
1740  * interrupts and bottom half handlers won't change it
1741  * from under us. It essentially blocks any incoming
1742  * packets, so that we won't get any new data or any
1743  * packets that change the state of the socket.
1744  *
1745  * While locked, BH processing will add new packets to
1746  * the backlog queue.  This queue is processed by the
1747  * owner of the socket lock right before it is released.
1748  *
1749  * Since ~2.3.5 it is also exclusive sleep lock serializing
1750  * accesses from user process context.
1751  */
1752 
sock_owned_by_me(const struct sock * sk)1753 static inline void sock_owned_by_me(const struct sock *sk)
1754 {
1755 #ifdef CONFIG_LOCKDEP
1756 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1757 #endif
1758 }
1759 
sock_not_owned_by_me(const struct sock * sk)1760 static inline void sock_not_owned_by_me(const struct sock *sk)
1761 {
1762 #ifdef CONFIG_LOCKDEP
1763 	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1764 #endif
1765 }
1766 
sock_owned_by_user(const struct sock * sk)1767 static inline bool sock_owned_by_user(const struct sock *sk)
1768 {
1769 	sock_owned_by_me(sk);
1770 	return sk->sk_lock.owned;
1771 }
1772 
sock_owned_by_user_nocheck(const struct sock * sk)1773 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1774 {
1775 	return sk->sk_lock.owned;
1776 }
1777 
sock_release_ownership(struct sock * sk)1778 static inline void sock_release_ownership(struct sock *sk)
1779 {
1780 	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1781 	sk->sk_lock.owned = 0;
1782 
1783 	/* The sk_lock has mutex_unlock() semantics: */
1784 	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1785 }
1786 
1787 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1788 static inline bool sock_allow_reclassification(const struct sock *csk)
1789 {
1790 	struct sock *sk = (struct sock *)csk;
1791 
1792 	return !sock_owned_by_user_nocheck(sk) &&
1793 		!spin_is_locked(&sk->sk_lock.slock);
1794 }
1795 
1796 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1797 		      struct proto *prot, int kern);
1798 void sk_free(struct sock *sk);
1799 void sk_net_refcnt_upgrade(struct sock *sk);
1800 void sk_destruct(struct sock *sk);
1801 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1802 
1803 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1804 			     gfp_t priority);
1805 void __sock_wfree(struct sk_buff *skb);
1806 void sock_wfree(struct sk_buff *skb);
1807 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1808 			     gfp_t priority);
1809 void skb_orphan_partial(struct sk_buff *skb);
1810 void sock_rfree(struct sk_buff *skb);
1811 void sock_efree(struct sk_buff *skb);
1812 #ifdef CONFIG_INET
1813 void sock_edemux(struct sk_buff *skb);
1814 void sock_pfree(struct sk_buff *skb);
1815 
skb_set_owner_edemux(struct sk_buff * skb,struct sock * sk)1816 static inline void skb_set_owner_edemux(struct sk_buff *skb, struct sock *sk)
1817 {
1818 	skb_orphan(skb);
1819 	if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1820 		skb->sk = sk;
1821 		skb->destructor = sock_edemux;
1822 	}
1823 }
1824 #else
1825 #define sock_edemux sock_efree
1826 #endif
1827 
1828 int sk_setsockopt(struct sock *sk, int level, int optname,
1829 		  sockptr_t optval, unsigned int optlen);
1830 int sock_setsockopt(struct socket *sock, int level, int op,
1831 		    sockptr_t optval, unsigned int optlen);
1832 int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1833 		       int optname, sockptr_t optval, int optlen);
1834 int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1835 		       int optname, sockptr_t optval, sockptr_t optlen);
1836 
1837 int sk_getsockopt(struct sock *sk, int level, int optname,
1838 		  sockptr_t optval, sockptr_t optlen);
1839 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1840 		   bool timeval, bool time32);
1841 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1842 				     unsigned long data_len, int noblock,
1843 				     int *errcode, int max_page_order);
1844 
sock_alloc_send_skb(struct sock * sk,unsigned long size,int noblock,int * errcode)1845 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1846 						  unsigned long size,
1847 						  int noblock, int *errcode)
1848 {
1849 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1850 }
1851 
1852 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1853 void *sock_kmemdup(struct sock *sk, const void *src,
1854 		   int size, gfp_t priority);
1855 void sock_kfree_s(struct sock *sk, void *mem, int size);
1856 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1857 void sk_send_sigurg(struct sock *sk);
1858 
sock_replace_proto(struct sock * sk,struct proto * proto)1859 static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1860 {
1861 	if (sk->sk_socket)
1862 		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1863 	WRITE_ONCE(sk->sk_prot, proto);
1864 }
1865 
1866 struct sockcm_cookie {
1867 	u64 transmit_time;
1868 	u32 mark;
1869 	u32 tsflags;
1870 	u32 ts_opt_id;
1871 	u32 priority;
1872 	u32 dmabuf_id;
1873 };
1874 
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1875 static inline void sockcm_init(struct sockcm_cookie *sockc,
1876 			       const struct sock *sk)
1877 {
1878 	*sockc = (struct sockcm_cookie) {
1879 		.mark = READ_ONCE(sk->sk_mark),
1880 		.tsflags = READ_ONCE(sk->sk_tsflags),
1881 		.priority = READ_ONCE(sk->sk_priority),
1882 	};
1883 }
1884 
1885 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1886 		     struct sockcm_cookie *sockc);
1887 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1888 		   struct sockcm_cookie *sockc);
1889 
1890 /*
1891  * Functions to fill in entries in struct proto_ops when a protocol
1892  * does not implement a particular function.
1893  */
1894 int sock_no_bind(struct socket *, struct sockaddr *, int);
1895 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1896 int sock_no_socketpair(struct socket *, struct socket *);
1897 int sock_no_accept(struct socket *, struct socket *, struct proto_accept_arg *);
1898 int sock_no_getname(struct socket *, struct sockaddr *, int);
1899 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1900 int sock_no_listen(struct socket *, int);
1901 int sock_no_shutdown(struct socket *, int);
1902 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1903 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1904 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1905 int sock_no_mmap(struct file *file, struct socket *sock,
1906 		 struct vm_area_struct *vma);
1907 
1908 /*
1909  * Functions to fill in entries in struct proto_ops when a protocol
1910  * uses the inet style.
1911  */
1912 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1913 				  char __user *optval, int __user *optlen);
1914 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1915 			int flags);
1916 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1917 			   sockptr_t optval, unsigned int optlen);
1918 
1919 void sk_common_release(struct sock *sk);
1920 
1921 /*
1922  *	Default socket callbacks and setup code
1923  */
1924 
1925 /* Initialise core socket variables using an explicit uid. */
1926 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1927 
1928 /* Initialise core socket variables.
1929  * Assumes struct socket *sock is embedded in a struct socket_alloc.
1930  */
1931 void sock_init_data(struct socket *sock, struct sock *sk);
1932 
1933 /*
1934  * Socket reference counting postulates.
1935  *
1936  * * Each user of socket SHOULD hold a reference count.
1937  * * Each access point to socket (an hash table bucket, reference from a list,
1938  *   running timer, skb in flight MUST hold a reference count.
1939  * * When reference count hits 0, it means it will never increase back.
1940  * * When reference count hits 0, it means that no references from
1941  *   outside exist to this socket and current process on current CPU
1942  *   is last user and may/should destroy this socket.
1943  * * sk_free is called from any context: process, BH, IRQ. When
1944  *   it is called, socket has no references from outside -> sk_free
1945  *   may release descendant resources allocated by the socket, but
1946  *   to the time when it is called, socket is NOT referenced by any
1947  *   hash tables, lists etc.
1948  * * Packets, delivered from outside (from network or from another process)
1949  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1950  *   when they sit in queue. Otherwise, packets will leak to hole, when
1951  *   socket is looked up by one cpu and unhasing is made by another CPU.
1952  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1953  *   (leak to backlog). Packet socket does all the processing inside
1954  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1955  *   use separate SMP lock, so that they are prone too.
1956  */
1957 
1958 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1959 static inline void sock_put(struct sock *sk)
1960 {
1961 	if (refcount_dec_and_test(&sk->sk_refcnt))
1962 		sk_free(sk);
1963 }
1964 /* Generic version of sock_put(), dealing with all sockets
1965  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1966  */
1967 void sock_gen_put(struct sock *sk);
1968 
1969 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1970 		     unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1971 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1972 				 const int nested)
1973 {
1974 	return __sk_receive_skb(sk, skb, nested, 1, true);
1975 }
1976 
sk_tx_queue_set(struct sock * sk,int tx_queue)1977 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1978 {
1979 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1980 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1981 		return;
1982 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1983 	 * other WRITE_ONCE() because socket lock might be not held.
1984 	 */
1985 	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1986 }
1987 
1988 #define NO_QUEUE_MAPPING	USHRT_MAX
1989 
sk_tx_queue_clear(struct sock * sk)1990 static inline void sk_tx_queue_clear(struct sock *sk)
1991 {
1992 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1993 	 * other WRITE_ONCE() because socket lock might be not held.
1994 	 */
1995 	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1996 }
1997 
sk_tx_queue_get(const struct sock * sk)1998 static inline int sk_tx_queue_get(const struct sock *sk)
1999 {
2000 	if (sk) {
2001 		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
2002 		 * and sk_tx_queue_set().
2003 		 */
2004 		int val = READ_ONCE(sk->sk_tx_queue_mapping);
2005 
2006 		if (val != NO_QUEUE_MAPPING)
2007 			return val;
2008 	}
2009 	return -1;
2010 }
2011 
__sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb,bool force_set)2012 static inline void __sk_rx_queue_set(struct sock *sk,
2013 				     const struct sk_buff *skb,
2014 				     bool force_set)
2015 {
2016 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2017 	if (skb_rx_queue_recorded(skb)) {
2018 		u16 rx_queue = skb_get_rx_queue(skb);
2019 
2020 		if (force_set ||
2021 		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2022 			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2023 	}
2024 #endif
2025 }
2026 
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)2027 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2028 {
2029 	__sk_rx_queue_set(sk, skb, true);
2030 }
2031 
sk_rx_queue_update(struct sock * sk,const struct sk_buff * skb)2032 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2033 {
2034 	__sk_rx_queue_set(sk, skb, false);
2035 }
2036 
sk_rx_queue_clear(struct sock * sk)2037 static inline void sk_rx_queue_clear(struct sock *sk)
2038 {
2039 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2040 	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2041 #endif
2042 }
2043 
sk_rx_queue_get(const struct sock * sk)2044 static inline int sk_rx_queue_get(const struct sock *sk)
2045 {
2046 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2047 	if (sk) {
2048 		int res = READ_ONCE(sk->sk_rx_queue_mapping);
2049 
2050 		if (res != NO_QUEUE_MAPPING)
2051 			return res;
2052 	}
2053 #endif
2054 
2055 	return -1;
2056 }
2057 
sk_set_socket(struct sock * sk,struct socket * sock)2058 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2059 {
2060 	sk->sk_socket = sock;
2061 	if (sock) {
2062 		WRITE_ONCE(sk->sk_uid, SOCK_INODE(sock)->i_uid);
2063 		WRITE_ONCE(sk->sk_ino, SOCK_INODE(sock)->i_ino);
2064 	}
2065 }
2066 
sk_sleep(struct sock * sk)2067 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2068 {
2069 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2070 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2071 }
2072 /* Detach socket from process context.
2073  * Announce socket dead, detach it from wait queue and inode.
2074  * Note that parent inode held reference count on this struct sock,
2075  * we do not release it in this function, because protocol
2076  * probably wants some additional cleanups or even continuing
2077  * to work with this socket (TCP).
2078  */
sock_orphan(struct sock * sk)2079 static inline void sock_orphan(struct sock *sk)
2080 {
2081 	write_lock_bh(&sk->sk_callback_lock);
2082 	sock_set_flag(sk, SOCK_DEAD);
2083 	sk_set_socket(sk, NULL);
2084 	sk->sk_wq  = NULL;
2085 	/* Note: sk_uid is unchanged. */
2086 	WRITE_ONCE(sk->sk_ino, 0);
2087 	write_unlock_bh(&sk->sk_callback_lock);
2088 }
2089 
sock_graft(struct sock * sk,struct socket * parent)2090 static inline void sock_graft(struct sock *sk, struct socket *parent)
2091 {
2092 	WARN_ON(parent->sk);
2093 	write_lock_bh(&sk->sk_callback_lock);
2094 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2095 	parent->sk = sk;
2096 	sk_set_socket(sk, parent);
2097 	security_sock_graft(sk, parent);
2098 	write_unlock_bh(&sk->sk_callback_lock);
2099 }
2100 
sock_i_ino(const struct sock * sk)2101 static inline unsigned long sock_i_ino(const struct sock *sk)
2102 {
2103 	/* Paired with WRITE_ONCE() in sock_graft() and sock_orphan() */
2104 	return READ_ONCE(sk->sk_ino);
2105 }
2106 
sk_uid(const struct sock * sk)2107 static inline kuid_t sk_uid(const struct sock *sk)
2108 {
2109 	/* Paired with WRITE_ONCE() in sockfs_setattr() */
2110 	return READ_ONCE(sk->sk_uid);
2111 }
2112 
sock_net_uid(const struct net * net,const struct sock * sk)2113 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2114 {
2115 	return sk ? sk_uid(sk) : make_kuid(net->user_ns, 0);
2116 }
2117 
net_tx_rndhash(void)2118 static inline u32 net_tx_rndhash(void)
2119 {
2120 	u32 v = get_random_u32();
2121 
2122 	return v ?: 1;
2123 }
2124 
sk_set_txhash(struct sock * sk)2125 static inline void sk_set_txhash(struct sock *sk)
2126 {
2127 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2128 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2129 }
2130 
sk_rethink_txhash(struct sock * sk)2131 static inline bool sk_rethink_txhash(struct sock *sk)
2132 {
2133 	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2134 		sk_set_txhash(sk);
2135 		return true;
2136 	}
2137 	return false;
2138 }
2139 
2140 static inline struct dst_entry *
__sk_dst_get(const struct sock * sk)2141 __sk_dst_get(const struct sock *sk)
2142 {
2143 	return rcu_dereference_check(sk->sk_dst_cache,
2144 				     lockdep_sock_is_held(sk));
2145 }
2146 
2147 static inline struct dst_entry *
sk_dst_get(const struct sock * sk)2148 sk_dst_get(const struct sock *sk)
2149 {
2150 	struct dst_entry *dst;
2151 
2152 	rcu_read_lock();
2153 	dst = rcu_dereference(sk->sk_dst_cache);
2154 	if (dst && !rcuref_get(&dst->__rcuref))
2155 		dst = NULL;
2156 	rcu_read_unlock();
2157 	return dst;
2158 }
2159 
__dst_negative_advice(struct sock * sk)2160 static inline void __dst_negative_advice(struct sock *sk)
2161 {
2162 	struct dst_entry *dst = __sk_dst_get(sk);
2163 
2164 	if (dst && dst->ops->negative_advice)
2165 		dst->ops->negative_advice(sk, dst);
2166 }
2167 
dst_negative_advice(struct sock * sk)2168 static inline void dst_negative_advice(struct sock *sk)
2169 {
2170 	sk_rethink_txhash(sk);
2171 	__dst_negative_advice(sk);
2172 }
2173 
2174 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)2175 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2176 {
2177 	struct dst_entry *old_dst;
2178 
2179 	sk_tx_queue_clear(sk);
2180 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2181 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2182 					    lockdep_sock_is_held(sk));
2183 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2184 	dst_release(old_dst);
2185 }
2186 
2187 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2188 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2189 {
2190 	struct dst_entry *old_dst;
2191 
2192 	sk_tx_queue_clear(sk);
2193 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2194 	old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst)));
2195 	dst_release(old_dst);
2196 }
2197 
2198 static inline void
__sk_dst_reset(struct sock * sk)2199 __sk_dst_reset(struct sock *sk)
2200 {
2201 	__sk_dst_set(sk, NULL);
2202 }
2203 
2204 static inline void
sk_dst_reset(struct sock * sk)2205 sk_dst_reset(struct sock *sk)
2206 {
2207 	sk_dst_set(sk, NULL);
2208 }
2209 
2210 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2211 
2212 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2213 
sk_dst_confirm(struct sock * sk)2214 static inline void sk_dst_confirm(struct sock *sk)
2215 {
2216 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2217 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2218 }
2219 
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2220 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2221 {
2222 	if (skb_get_dst_pending_confirm(skb)) {
2223 		struct sock *sk = skb->sk;
2224 
2225 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2226 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2227 		neigh_confirm(n);
2228 	}
2229 }
2230 
2231 bool sk_mc_loop(const struct sock *sk);
2232 
sk_can_gso(const struct sock * sk)2233 static inline bool sk_can_gso(const struct sock *sk)
2234 {
2235 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2236 }
2237 
2238 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2239 
sk_gso_disable(struct sock * sk)2240 static inline void sk_gso_disable(struct sock *sk)
2241 {
2242 	sk->sk_gso_disabled = 1;
2243 	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2244 }
2245 
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2246 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2247 					   struct iov_iter *from, char *to,
2248 					   int copy, int offset)
2249 {
2250 	if (skb->ip_summed == CHECKSUM_NONE) {
2251 		__wsum csum = 0;
2252 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2253 			return -EFAULT;
2254 		skb->csum = csum_block_add(skb->csum, csum, offset);
2255 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2256 		if (!copy_from_iter_full_nocache(to, copy, from))
2257 			return -EFAULT;
2258 	} else if (!copy_from_iter_full(to, copy, from))
2259 		return -EFAULT;
2260 
2261 	return 0;
2262 }
2263 
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2264 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2265 				       struct iov_iter *from, int copy)
2266 {
2267 	int err, offset = skb->len;
2268 
2269 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2270 				       copy, offset);
2271 	if (err)
2272 		__skb_trim(skb, offset);
2273 
2274 	return err;
2275 }
2276 
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2277 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2278 					   struct sk_buff *skb,
2279 					   struct page *page,
2280 					   int off, int copy)
2281 {
2282 	int err;
2283 
2284 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2285 				       copy, skb->len);
2286 	if (err)
2287 		return err;
2288 
2289 	skb_len_add(skb, copy);
2290 	sk_wmem_queued_add(sk, copy);
2291 	sk_mem_charge(sk, copy);
2292 	return 0;
2293 }
2294 
2295 /**
2296  * sk_wmem_alloc_get - returns write allocations
2297  * @sk: socket
2298  *
2299  * Return: sk_wmem_alloc minus initial offset of one
2300  */
sk_wmem_alloc_get(const struct sock * sk)2301 static inline int sk_wmem_alloc_get(const struct sock *sk)
2302 {
2303 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2304 }
2305 
2306 /**
2307  * sk_rmem_alloc_get - returns read allocations
2308  * @sk: socket
2309  *
2310  * Return: sk_rmem_alloc
2311  */
sk_rmem_alloc_get(const struct sock * sk)2312 static inline int sk_rmem_alloc_get(const struct sock *sk)
2313 {
2314 	return atomic_read(&sk->sk_rmem_alloc);
2315 }
2316 
2317 /**
2318  * sk_has_allocations - check if allocations are outstanding
2319  * @sk: socket
2320  *
2321  * Return: true if socket has write or read allocations
2322  */
sk_has_allocations(const struct sock * sk)2323 static inline bool sk_has_allocations(const struct sock *sk)
2324 {
2325 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2326 }
2327 
2328 /**
2329  * skwq_has_sleeper - check if there are any waiting processes
2330  * @wq: struct socket_wq
2331  *
2332  * Return: true if socket_wq has waiting processes
2333  *
2334  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2335  * barrier call. They were added due to the race found within the tcp code.
2336  *
2337  * Consider following tcp code paths::
2338  *
2339  *   CPU1                CPU2
2340  *   sys_select          receive packet
2341  *   ...                 ...
2342  *   __add_wait_queue    update tp->rcv_nxt
2343  *   ...                 ...
2344  *   tp->rcv_nxt check   sock_def_readable
2345  *   ...                 {
2346  *   schedule               rcu_read_lock();
2347  *                          wq = rcu_dereference(sk->sk_wq);
2348  *                          if (wq && waitqueue_active(&wq->wait))
2349  *                              wake_up_interruptible(&wq->wait)
2350  *                          ...
2351  *                       }
2352  *
2353  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2354  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2355  * could then endup calling schedule and sleep forever if there are no more
2356  * data on the socket.
2357  *
2358  */
skwq_has_sleeper(struct socket_wq * wq)2359 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2360 {
2361 	return wq && wq_has_sleeper(&wq->wait);
2362 }
2363 
2364 /**
2365  * sock_poll_wait - wrapper for the poll_wait call.
2366  * @filp:           file
2367  * @sock:           socket to wait on
2368  * @p:              poll_table
2369  *
2370  * See the comments in the wq_has_sleeper function.
2371  */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2372 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2373 				  poll_table *p)
2374 {
2375 	/* Provides a barrier we need to be sure we are in sync
2376 	 * with the socket flags modification.
2377 	 *
2378 	 * This memory barrier is paired in the wq_has_sleeper.
2379 	 */
2380 	poll_wait(filp, &sock->wq.wait, p);
2381 }
2382 
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2383 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2384 {
2385 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2386 	u32 txhash = READ_ONCE(sk->sk_txhash);
2387 
2388 	if (txhash) {
2389 		skb->l4_hash = 1;
2390 		skb->hash = txhash;
2391 	}
2392 }
2393 
2394 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2395 
2396 /*
2397  *	Queue a received datagram if it will fit. Stream and sequenced
2398  *	protocols can't normally use this as they need to fit buffers in
2399  *	and play with them.
2400  *
2401  *	Inlined as it's very short and called for pretty much every
2402  *	packet ever received.
2403  */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2404 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2405 {
2406 	skb_orphan(skb);
2407 	skb->sk = sk;
2408 	skb->destructor = sock_rfree;
2409 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2410 	sk_mem_charge(sk, skb->truesize);
2411 }
2412 
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2413 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2414 {
2415 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2416 		skb_orphan(skb);
2417 		skb->destructor = sock_efree;
2418 		skb->sk = sk;
2419 		return true;
2420 	}
2421 	return false;
2422 }
2423 
skb_clone_and_charge_r(struct sk_buff * skb,struct sock * sk)2424 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2425 {
2426 	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2427 	if (skb) {
2428 		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2429 			skb_set_owner_r(skb, sk);
2430 			return skb;
2431 		}
2432 		__kfree_skb(skb);
2433 	}
2434 	return NULL;
2435 }
2436 
skb_prepare_for_gro(struct sk_buff * skb)2437 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2438 {
2439 	if (skb->destructor != sock_wfree) {
2440 		skb_orphan(skb);
2441 		return;
2442 	}
2443 	skb->slow_gro = 1;
2444 }
2445 
2446 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2447 		    unsigned long expires);
2448 
2449 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2450 
2451 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2452 
2453 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2454 			struct sk_buff *skb, unsigned int flags,
2455 			void (*destructor)(struct sock *sk,
2456 					   struct sk_buff *skb));
2457 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2458 
2459 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2460 			      enum skb_drop_reason *reason);
2461 
sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)2462 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2463 {
2464 	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2465 }
2466 
2467 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2468 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2469 
2470 /*
2471  *	Recover an error report and clear atomically
2472  */
2473 
sock_error(struct sock * sk)2474 static inline int sock_error(struct sock *sk)
2475 {
2476 	int err;
2477 
2478 	/* Avoid an atomic operation for the common case.
2479 	 * This is racy since another cpu/thread can change sk_err under us.
2480 	 */
2481 	if (likely(data_race(!sk->sk_err)))
2482 		return 0;
2483 
2484 	err = xchg(&sk->sk_err, 0);
2485 	return -err;
2486 }
2487 
2488 void sk_error_report(struct sock *sk);
2489 
sock_wspace(struct sock * sk)2490 static inline unsigned long sock_wspace(struct sock *sk)
2491 {
2492 	int amt = 0;
2493 
2494 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2495 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2496 		if (amt < 0)
2497 			amt = 0;
2498 	}
2499 	return amt;
2500 }
2501 
2502 /* Note:
2503  *  We use sk->sk_wq_raw, from contexts knowing this
2504  *  pointer is not NULL and cannot disappear/change.
2505  */
sk_set_bit(int nr,struct sock * sk)2506 static inline void sk_set_bit(int nr, struct sock *sk)
2507 {
2508 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2509 	    !sock_flag(sk, SOCK_FASYNC))
2510 		return;
2511 
2512 	set_bit(nr, &sk->sk_wq_raw->flags);
2513 }
2514 
sk_clear_bit(int nr,struct sock * sk)2515 static inline void sk_clear_bit(int nr, struct sock *sk)
2516 {
2517 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2518 	    !sock_flag(sk, SOCK_FASYNC))
2519 		return;
2520 
2521 	clear_bit(nr, &sk->sk_wq_raw->flags);
2522 }
2523 
sk_wake_async(const struct sock * sk,int how,int band)2524 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2525 {
2526 	if (sock_flag(sk, SOCK_FASYNC)) {
2527 		rcu_read_lock();
2528 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2529 		rcu_read_unlock();
2530 	}
2531 }
2532 
sk_wake_async_rcu(const struct sock * sk,int how,int band)2533 static inline void sk_wake_async_rcu(const struct sock *sk, int how, int band)
2534 {
2535 	if (unlikely(sock_flag(sk, SOCK_FASYNC)))
2536 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2537 }
2538 
2539 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2540  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2541  * Note: for send buffers, TCP works better if we can build two skbs at
2542  * minimum.
2543  */
2544 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2545 
2546 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2547 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2548 
sk_stream_moderate_sndbuf(struct sock * sk)2549 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2550 {
2551 	u32 val;
2552 
2553 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2554 		return;
2555 
2556 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2557 	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2558 
2559 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2560 }
2561 
2562 /**
2563  * sk_page_frag - return an appropriate page_frag
2564  * @sk: socket
2565  *
2566  * Use the per task page_frag instead of the per socket one for
2567  * optimization when we know that we're in process context and own
2568  * everything that's associated with %current.
2569  *
2570  * Both direct reclaim and page faults can nest inside other
2571  * socket operations and end up recursing into sk_page_frag()
2572  * while it's already in use: explicitly avoid task page_frag
2573  * when users disable sk_use_task_frag.
2574  *
2575  * Return: a per task page_frag if context allows that,
2576  * otherwise a per socket one.
2577  */
sk_page_frag(struct sock * sk)2578 static inline struct page_frag *sk_page_frag(struct sock *sk)
2579 {
2580 	if (sk->sk_use_task_frag)
2581 		return &current->task_frag;
2582 
2583 	return &sk->sk_frag;
2584 }
2585 
2586 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2587 
2588 /*
2589  *	Default write policy as shown to user space via poll/select/SIGIO
2590  */
sock_writeable(const struct sock * sk)2591 static inline bool sock_writeable(const struct sock *sk)
2592 {
2593 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2594 }
2595 
gfp_any(void)2596 static inline gfp_t gfp_any(void)
2597 {
2598 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2599 }
2600 
gfp_memcg_charge(void)2601 static inline gfp_t gfp_memcg_charge(void)
2602 {
2603 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2604 }
2605 
sock_rcvtimeo(const struct sock * sk,bool noblock)2606 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2607 {
2608 	return noblock ? 0 : READ_ONCE(sk->sk_rcvtimeo);
2609 }
2610 
sock_sndtimeo(const struct sock * sk,bool noblock)2611 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2612 {
2613 	return noblock ? 0 : READ_ONCE(sk->sk_sndtimeo);
2614 }
2615 
sock_rcvlowat(const struct sock * sk,int waitall,int len)2616 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2617 {
2618 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2619 
2620 	return v ?: 1;
2621 }
2622 
2623 /* Alas, with timeout socket operations are not restartable.
2624  * Compare this to poll().
2625  */
sock_intr_errno(long timeo)2626 static inline int sock_intr_errno(long timeo)
2627 {
2628 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2629 }
2630 
2631 struct sock_skb_cb {
2632 	u32 dropcount;
2633 };
2634 
2635 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2636  * using skb->cb[] would keep using it directly and utilize its
2637  * alignment guarantee.
2638  */
2639 #define SOCK_SKB_CB_OFFSET (sizeof_field(struct sk_buff, cb) - \
2640 			    sizeof(struct sock_skb_cb))
2641 
2642 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2643 			    SOCK_SKB_CB_OFFSET))
2644 
2645 #define sock_skb_cb_check_size(size) \
2646 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2647 
2648 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2649 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2650 {
2651 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2652 						atomic_read(&sk->sk_drops) : 0;
2653 }
2654 
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2655 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2656 {
2657 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2658 
2659 	atomic_add(segs, &sk->sk_drops);
2660 }
2661 
sock_read_timestamp(struct sock * sk)2662 static inline ktime_t sock_read_timestamp(struct sock *sk)
2663 {
2664 #if BITS_PER_LONG==32
2665 	unsigned int seq;
2666 	ktime_t kt;
2667 
2668 	do {
2669 		seq = read_seqbegin(&sk->sk_stamp_seq);
2670 		kt = sk->sk_stamp;
2671 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2672 
2673 	return kt;
2674 #else
2675 	return READ_ONCE(sk->sk_stamp);
2676 #endif
2677 }
2678 
sock_write_timestamp(struct sock * sk,ktime_t kt)2679 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2680 {
2681 #if BITS_PER_LONG==32
2682 	write_seqlock(&sk->sk_stamp_seq);
2683 	sk->sk_stamp = kt;
2684 	write_sequnlock(&sk->sk_stamp_seq);
2685 #else
2686 	WRITE_ONCE(sk->sk_stamp, kt);
2687 #endif
2688 }
2689 
2690 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2691 			   struct sk_buff *skb);
2692 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2693 			     struct sk_buff *skb);
2694 
2695 bool skb_has_tx_timestamp(struct sk_buff *skb, const struct sock *sk);
2696 int skb_get_tx_timestamp(struct sk_buff *skb, struct sock *sk,
2697 			 struct timespec64 *ts);
2698 
2699 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2700 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2701 {
2702 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2703 	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2704 	ktime_t kt = skb->tstamp;
2705 	/*
2706 	 * generate control messages if
2707 	 * - receive time stamping in software requested
2708 	 * - software time stamp available and wanted
2709 	 * - hardware time stamps available and wanted
2710 	 */
2711 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2712 	    (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2713 	    (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2714 	    (hwtstamps->hwtstamp &&
2715 	     (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2716 		__sock_recv_timestamp(msg, sk, skb);
2717 	else
2718 		sock_write_timestamp(sk, kt);
2719 
2720 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2721 		__sock_recv_wifi_status(msg, sk, skb);
2722 }
2723 
2724 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2725 		       struct sk_buff *skb);
2726 
2727 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_cmsgs(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2728 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2729 				   struct sk_buff *skb)
2730 {
2731 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2732 			   (1UL << SOCK_RCVTSTAMP)			| \
2733 			   (1UL << SOCK_RCVMARK)			| \
2734 			   (1UL << SOCK_RCVPRIORITY)			| \
2735 			   (1UL << SOCK_TIMESTAMPING_ANY))
2736 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2737 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2738 
2739 	if (READ_ONCE(sk->sk_flags) & FLAGS_RECV_CMSGS)
2740 		__sock_recv_cmsgs(msg, sk, skb);
2741 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2742 		sock_write_timestamp(sk, skb->tstamp);
2743 	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2744 		sock_write_timestamp(sk, 0);
2745 }
2746 
2747 void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags);
2748 
2749 /**
2750  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2751  * @sk:		socket sending this packet
2752  * @sockc:	pointer to socket cmsg cookie to get timestamping info
2753  * @tx_flags:	completed with instructions for time stamping
2754  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2755  *
2756  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2757  */
_sock_tx_timestamp(struct sock * sk,const struct sockcm_cookie * sockc,__u8 * tx_flags,__u32 * tskey)2758 static inline void _sock_tx_timestamp(struct sock *sk,
2759 				      const struct sockcm_cookie *sockc,
2760 				      __u8 *tx_flags, __u32 *tskey)
2761 {
2762 	__u32 tsflags = sockc->tsflags;
2763 
2764 	if (unlikely(tsflags)) {
2765 		__sock_tx_timestamp(tsflags, tx_flags);
2766 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2767 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) {
2768 			if (tsflags & SOCKCM_FLAG_TS_OPT_ID)
2769 				*tskey = sockc->ts_opt_id;
2770 			else
2771 				*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2772 		}
2773 	}
2774 }
2775 
sock_tx_timestamp(struct sock * sk,const struct sockcm_cookie * sockc,__u8 * tx_flags)2776 static inline void sock_tx_timestamp(struct sock *sk,
2777 				     const struct sockcm_cookie *sockc,
2778 				     __u8 *tx_flags)
2779 {
2780 	_sock_tx_timestamp(sk, sockc, tx_flags, NULL);
2781 }
2782 
skb_setup_tx_timestamp(struct sk_buff * skb,const struct sockcm_cookie * sockc)2783 static inline void skb_setup_tx_timestamp(struct sk_buff *skb,
2784 					  const struct sockcm_cookie *sockc)
2785 {
2786 	_sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags,
2787 			   &skb_shinfo(skb)->tskey);
2788 }
2789 
sk_is_inet(const struct sock * sk)2790 static inline bool sk_is_inet(const struct sock *sk)
2791 {
2792 	int family = READ_ONCE(sk->sk_family);
2793 
2794 	return family == AF_INET || family == AF_INET6;
2795 }
2796 
sk_is_tcp(const struct sock * sk)2797 static inline bool sk_is_tcp(const struct sock *sk)
2798 {
2799 	return sk_is_inet(sk) &&
2800 	       sk->sk_type == SOCK_STREAM &&
2801 	       sk->sk_protocol == IPPROTO_TCP;
2802 }
2803 
sk_is_udp(const struct sock * sk)2804 static inline bool sk_is_udp(const struct sock *sk)
2805 {
2806 	return sk_is_inet(sk) &&
2807 	       sk->sk_type == SOCK_DGRAM &&
2808 	       sk->sk_protocol == IPPROTO_UDP;
2809 }
2810 
sk_is_unix(const struct sock * sk)2811 static inline bool sk_is_unix(const struct sock *sk)
2812 {
2813 	return sk->sk_family == AF_UNIX;
2814 }
2815 
sk_is_stream_unix(const struct sock * sk)2816 static inline bool sk_is_stream_unix(const struct sock *sk)
2817 {
2818 	return sk_is_unix(sk) && sk->sk_type == SOCK_STREAM;
2819 }
2820 
sk_is_vsock(const struct sock * sk)2821 static inline bool sk_is_vsock(const struct sock *sk)
2822 {
2823 	return sk->sk_family == AF_VSOCK;
2824 }
2825 
sk_may_scm_recv(const struct sock * sk)2826 static inline bool sk_may_scm_recv(const struct sock *sk)
2827 {
2828 	return (IS_ENABLED(CONFIG_UNIX) && sk->sk_family == AF_UNIX) ||
2829 		sk->sk_family == AF_NETLINK ||
2830 		(IS_ENABLED(CONFIG_BT) && sk->sk_family == AF_BLUETOOTH);
2831 }
2832 
2833 /**
2834  * sk_eat_skb - Release a skb if it is no longer needed
2835  * @sk: socket to eat this skb from
2836  * @skb: socket buffer to eat
2837  *
2838  * This routine must be called with interrupts disabled or with the socket
2839  * locked so that the sk_buff queue operation is ok.
2840 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2841 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2842 {
2843 	__skb_unlink(skb, &sk->sk_receive_queue);
2844 	__kfree_skb(skb);
2845 }
2846 
2847 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2848 skb_sk_is_prefetched(struct sk_buff *skb)
2849 {
2850 #ifdef CONFIG_INET
2851 	return skb->destructor == sock_pfree;
2852 #else
2853 	return false;
2854 #endif /* CONFIG_INET */
2855 }
2856 
2857 /* This helper checks if a socket is a full socket,
2858  * ie _not_ a timewait or request socket.
2859  */
sk_fullsock(const struct sock * sk)2860 static inline bool sk_fullsock(const struct sock *sk)
2861 {
2862 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2863 }
2864 
2865 static inline bool
sk_is_refcounted(struct sock * sk)2866 sk_is_refcounted(struct sock *sk)
2867 {
2868 	/* Only full sockets have sk->sk_flags. */
2869 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2870 }
2871 
2872 static inline bool
sk_requests_wifi_status(struct sock * sk)2873 sk_requests_wifi_status(struct sock *sk)
2874 {
2875 	return sk && sk_fullsock(sk) && sock_flag(sk, SOCK_WIFI_STATUS);
2876 }
2877 
2878 /* Checks if this SKB belongs to an HW offloaded socket
2879  * and whether any SW fallbacks are required based on dev.
2880  * Check decrypted mark in case skb_orphan() cleared socket.
2881  */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2882 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2883 						   struct net_device *dev)
2884 {
2885 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2886 	struct sock *sk = skb->sk;
2887 
2888 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2889 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2890 	} else if (unlikely(skb_is_decrypted(skb))) {
2891 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2892 		kfree_skb(skb);
2893 		skb = NULL;
2894 	}
2895 #endif
2896 
2897 	return skb;
2898 }
2899 
2900 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2901  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2902  */
sk_listener(const struct sock * sk)2903 static inline bool sk_listener(const struct sock *sk)
2904 {
2905 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2906 }
2907 
2908 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT
2909  * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE)
2910  * TCP RST and ACK can be attached to TIME_WAIT.
2911  */
sk_listener_or_tw(const struct sock * sk)2912 static inline bool sk_listener_or_tw(const struct sock *sk)
2913 {
2914 	return (1 << READ_ONCE(sk->sk_state)) &
2915 	       (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT);
2916 }
2917 
2918 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2919 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2920 		       int type);
2921 
2922 bool sk_ns_capable(const struct sock *sk,
2923 		   struct user_namespace *user_ns, int cap);
2924 bool sk_capable(const struct sock *sk, int cap);
2925 bool sk_net_capable(const struct sock *sk, int cap);
2926 
2927 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2928 
2929 /* Take into consideration the size of the struct sk_buff overhead in the
2930  * determination of these values, since that is non-constant across
2931  * platforms.  This makes socket queueing behavior and performance
2932  * not depend upon such differences.
2933  */
2934 #define _SK_MEM_PACKETS		256
2935 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2936 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2937 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2938 
2939 extern __u32 sysctl_wmem_max;
2940 extern __u32 sysctl_rmem_max;
2941 
2942 extern __u32 sysctl_wmem_default;
2943 extern __u32 sysctl_rmem_default;
2944 
2945 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2946 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2947 
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2948 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2949 {
2950 	/* Does this proto have per netns sysctl_wmem ? */
2951 	if (proto->sysctl_wmem_offset)
2952 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2953 
2954 	return READ_ONCE(*proto->sysctl_wmem);
2955 }
2956 
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2957 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2958 {
2959 	/* Does this proto have per netns sysctl_rmem ? */
2960 	if (proto->sysctl_rmem_offset)
2961 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2962 
2963 	return READ_ONCE(*proto->sysctl_rmem);
2964 }
2965 
2966 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2967  * Some wifi drivers need to tweak it to get more chunks.
2968  * They can use this helper from their ndo_start_xmit()
2969  */
sk_pacing_shift_update(struct sock * sk,int val)2970 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2971 {
2972 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2973 		return;
2974 	WRITE_ONCE(sk->sk_pacing_shift, val);
2975 }
2976 
2977 /* if a socket is bound to a device, check that the given device
2978  * index is either the same or that the socket is bound to an L3
2979  * master device and the given device index is also enslaved to
2980  * that L3 master
2981  */
sk_dev_equal_l3scope(struct sock * sk,int dif)2982 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2983 {
2984 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2985 	int mdif;
2986 
2987 	if (!bound_dev_if || bound_dev_if == dif)
2988 		return true;
2989 
2990 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2991 	if (mdif && mdif == bound_dev_if)
2992 		return true;
2993 
2994 	return false;
2995 }
2996 
2997 void sock_def_readable(struct sock *sk);
2998 
2999 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
3000 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
3001 int sock_set_timestamping(struct sock *sk, int optname,
3002 			  struct so_timestamping timestamping);
3003 
3004 #if defined(CONFIG_CGROUP_BPF)
3005 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op);
3006 #else
bpf_skops_tx_timestamping(struct sock * sk,struct sk_buff * skb,int op)3007 static inline void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
3008 {
3009 }
3010 #endif
3011 void sock_no_linger(struct sock *sk);
3012 void sock_set_keepalive(struct sock *sk);
3013 void sock_set_priority(struct sock *sk, u32 priority);
3014 void sock_set_rcvbuf(struct sock *sk, int val);
3015 void sock_set_mark(struct sock *sk, u32 val);
3016 void sock_set_reuseaddr(struct sock *sk);
3017 void sock_set_reuseport(struct sock *sk);
3018 void sock_set_sndtimeo(struct sock *sk, s64 secs);
3019 
3020 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
3021 
3022 int sock_get_timeout(long timeo, void *optval, bool old_timeval);
3023 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
3024 			   sockptr_t optval, int optlen, bool old_timeval);
3025 
3026 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
3027 		     void __user *arg, void *karg, size_t size);
3028 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
sk_is_readable(struct sock * sk)3029 static inline bool sk_is_readable(struct sock *sk)
3030 {
3031 	const struct proto *prot = READ_ONCE(sk->sk_prot);
3032 
3033 	if (prot->sock_is_readable)
3034 		return prot->sock_is_readable(sk);
3035 
3036 	return false;
3037 }
3038 #endif	/* _SOCK_H */
3039