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v4.17
 
   1/*
   2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   3 *		operating system.  INET is implemented using the  BSD Socket
   4 *		interface as the means of communication with the user level.
   5 *
   6 *		Definitions for the AF_INET socket handler.
   7 *
   8 * Version:	@(#)sock.h	1.0.4	05/13/93
   9 *
  10 * Authors:	Ross Biro
  11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *		Corey Minyard <wf-rch!minyard@relay.EU.net>
  13 *		Florian La Roche <flla@stud.uni-sb.de>
  14 *
  15 * Fixes:
  16 *		Alan Cox	:	Volatiles in skbuff pointers. See
  17 *					skbuff comments. May be overdone,
  18 *					better to prove they can be removed
  19 *					than the reverse.
  20 *		Alan Cox	:	Added a zapped field for tcp to note
  21 *					a socket is reset and must stay shut up
  22 *		Alan Cox	:	New fields for options
  23 *	Pauline Middelink	:	identd support
  24 *		Alan Cox	:	Eliminate low level recv/recvfrom
  25 *		David S. Miller	:	New socket lookup architecture.
  26 *              Steve Whitehouse:       Default routines for sock_ops
  27 *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
  28 *              			protinfo be just a void pointer, as the
  29 *              			protocol specific parts were moved to
  30 *              			respective headers and ipv4/v6, etc now
  31 *              			use private slabcaches for its socks
  32 *              Pedro Hortas	:	New flags field for socket options
  33 *
  34 *
  35 *		This program is free software; you can redistribute it and/or
  36 *		modify it under the terms of the GNU General Public License
  37 *		as published by the Free Software Foundation; either version
  38 *		2 of the License, or (at your option) any later version.
  39 */
  40#ifndef _SOCK_H
  41#define _SOCK_H
  42
  43#include <linux/hardirq.h>
  44#include <linux/kernel.h>
  45#include <linux/list.h>
  46#include <linux/list_nulls.h>
  47#include <linux/timer.h>
  48#include <linux/cache.h>
  49#include <linux/bitops.h>
  50#include <linux/lockdep.h>
  51#include <linux/netdevice.h>
  52#include <linux/skbuff.h>	/* struct sk_buff */
  53#include <linux/mm.h>
  54#include <linux/security.h>
  55#include <linux/slab.h>
  56#include <linux/uaccess.h>
  57#include <linux/page_counter.h>
  58#include <linux/memcontrol.h>
  59#include <linux/static_key.h>
  60#include <linux/sched.h>
  61#include <linux/wait.h>
  62#include <linux/cgroup-defs.h>
  63#include <linux/rbtree.h>
  64#include <linux/filter.h>
  65#include <linux/rculist_nulls.h>
  66#include <linux/poll.h>
  67
 
  68#include <linux/atomic.h>
  69#include <linux/refcount.h>
 
  70#include <net/dst.h>
  71#include <net/checksum.h>
  72#include <net/tcp_states.h>
  73#include <linux/net_tstamp.h>
  74#include <net/smc.h>
  75#include <net/l3mdev.h>
 
  76
  77/*
  78 * This structure really needs to be cleaned up.
  79 * Most of it is for TCP, and not used by any of
  80 * the other protocols.
  81 */
  82
  83/* Define this to get the SOCK_DBG debugging facility. */
  84#define SOCK_DEBUGGING
  85#ifdef SOCK_DEBUGGING
  86#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
  87					printk(KERN_DEBUG msg); } while (0)
  88#else
  89/* Validate arguments and do nothing */
  90static inline __printf(2, 3)
  91void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
  92{
  93}
  94#endif
  95
  96/* This is the per-socket lock.  The spinlock provides a synchronization
  97 * between user contexts and software interrupt processing, whereas the
  98 * mini-semaphore synchronizes multiple users amongst themselves.
  99 */
 100typedef struct {
 101	spinlock_t		slock;
 102	int			owned;
 103	wait_queue_head_t	wq;
 104	/*
 105	 * We express the mutex-alike socket_lock semantics
 106	 * to the lock validator by explicitly managing
 107	 * the slock as a lock variant (in addition to
 108	 * the slock itself):
 109	 */
 110#ifdef CONFIG_DEBUG_LOCK_ALLOC
 111	struct lockdep_map dep_map;
 112#endif
 113} socket_lock_t;
 114
 115struct sock;
 116struct proto;
 117struct net;
 118
 119typedef __u32 __bitwise __portpair;
 120typedef __u64 __bitwise __addrpair;
 121
 122/**
 123 *	struct sock_common - minimal network layer representation of sockets
 124 *	@skc_daddr: Foreign IPv4 addr
 125 *	@skc_rcv_saddr: Bound local IPv4 addr
 
 126 *	@skc_hash: hash value used with various protocol lookup tables
 127 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
 128 *	@skc_dport: placeholder for inet_dport/tw_dport
 129 *	@skc_num: placeholder for inet_num/tw_num
 
 130 *	@skc_family: network address family
 131 *	@skc_state: Connection state
 132 *	@skc_reuse: %SO_REUSEADDR setting
 133 *	@skc_reuseport: %SO_REUSEPORT setting
 
 
 134 *	@skc_bound_dev_if: bound device index if != 0
 135 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
 136 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
 137 *	@skc_prot: protocol handlers inside a network family
 138 *	@skc_net: reference to the network namespace of this socket
 
 
 
 139 *	@skc_node: main hash linkage for various protocol lookup tables
 140 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
 141 *	@skc_tx_queue_mapping: tx queue number for this connection
 
 142 *	@skc_flags: place holder for sk_flags
 143 *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
 144 *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
 
 
 
 
 145 *	@skc_incoming_cpu: record/match cpu processing incoming packets
 
 
 
 
 146 *	@skc_refcnt: reference count
 147 *
 148 *	This is the minimal network layer representation of sockets, the header
 149 *	for struct sock and struct inet_timewait_sock.
 150 */
 151struct sock_common {
 152	/* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
 153	 * address on 64bit arches : cf INET_MATCH()
 154	 */
 155	union {
 156		__addrpair	skc_addrpair;
 157		struct {
 158			__be32	skc_daddr;
 159			__be32	skc_rcv_saddr;
 160		};
 161	};
 162	union  {
 163		unsigned int	skc_hash;
 164		__u16		skc_u16hashes[2];
 165	};
 166	/* skc_dport && skc_num must be grouped as well */
 167	union {
 168		__portpair	skc_portpair;
 169		struct {
 170			__be16	skc_dport;
 171			__u16	skc_num;
 172		};
 173	};
 174
 175	unsigned short		skc_family;
 176	volatile unsigned char	skc_state;
 177	unsigned char		skc_reuse:4;
 178	unsigned char		skc_reuseport:1;
 179	unsigned char		skc_ipv6only:1;
 180	unsigned char		skc_net_refcnt:1;
 181	int			skc_bound_dev_if;
 182	union {
 183		struct hlist_node	skc_bind_node;
 184		struct hlist_node	skc_portaddr_node;
 185	};
 186	struct proto		*skc_prot;
 187	possible_net_t		skc_net;
 188
 189#if IS_ENABLED(CONFIG_IPV6)
 190	struct in6_addr		skc_v6_daddr;
 191	struct in6_addr		skc_v6_rcv_saddr;
 192#endif
 193
 194	atomic64_t		skc_cookie;
 195
 196	/* following fields are padding to force
 197	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
 198	 * assuming IPV6 is enabled. We use this padding differently
 199	 * for different kind of 'sockets'
 200	 */
 201	union {
 202		unsigned long	skc_flags;
 203		struct sock	*skc_listener; /* request_sock */
 204		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
 205	};
 206	/*
 207	 * fields between dontcopy_begin/dontcopy_end
 208	 * are not copied in sock_copy()
 209	 */
 210	/* private: */
 211	int			skc_dontcopy_begin[0];
 212	/* public: */
 213	union {
 214		struct hlist_node	skc_node;
 215		struct hlist_nulls_node skc_nulls_node;
 216	};
 217	int			skc_tx_queue_mapping;
 
 
 
 218	union {
 219		int		skc_incoming_cpu;
 220		u32		skc_rcv_wnd;
 221		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
 222	};
 223
 224	refcount_t		skc_refcnt;
 225	/* private: */
 226	int                     skc_dontcopy_end[0];
 227	union {
 228		u32		skc_rxhash;
 229		u32		skc_window_clamp;
 230		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
 231	};
 232	/* public: */
 233};
 234
 
 
 
 235/**
 236  *	struct sock - network layer representation of sockets
 237  *	@__sk_common: shared layout with inet_timewait_sock
 238  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
 239  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
 240  *	@sk_lock:	synchronizer
 241  *	@sk_kern_sock: True if sock is using kernel lock classes
 242  *	@sk_rcvbuf: size of receive buffer in bytes
 243  *	@sk_wq: sock wait queue and async head
 244  *	@sk_rx_dst: receive input route used by early demux
 
 
 245  *	@sk_dst_cache: destination cache
 246  *	@sk_dst_pending_confirm: need to confirm neighbour
 247  *	@sk_policy: flow policy
 248  *	@sk_receive_queue: incoming packets
 249  *	@sk_wmem_alloc: transmit queue bytes committed
 250  *	@sk_tsq_flags: TCP Small Queues flags
 251  *	@sk_write_queue: Packet sending queue
 252  *	@sk_omem_alloc: "o" is "option" or "other"
 253  *	@sk_wmem_queued: persistent queue size
 254  *	@sk_forward_alloc: space allocated forward
 
 255  *	@sk_napi_id: id of the last napi context to receive data for sk
 256  *	@sk_ll_usec: usecs to busypoll when there is no data
 257  *	@sk_allocation: allocation mode
 258  *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
 259  *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
 260  *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
 261  *	@sk_sndbuf: size of send buffer in bytes
 262  *	@__sk_flags_offset: empty field used to determine location of bitfield
 263  *	@sk_padding: unused element for alignment
 264  *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
 265  *	@sk_no_check_rx: allow zero checksum in RX packets
 266  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
 267  *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
 268  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
 269  *	@sk_gso_max_size: Maximum GSO segment size to build
 270  *	@sk_gso_max_segs: Maximum number of GSO segments
 271  *	@sk_pacing_shift: scaling factor for TCP Small Queues
 272  *	@sk_lingertime: %SO_LINGER l_linger setting
 273  *	@sk_backlog: always used with the per-socket spinlock held
 274  *	@sk_callback_lock: used with the callbacks in the end of this struct
 275  *	@sk_error_queue: rarely used
 276  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
 277  *			  IPV6_ADDRFORM for instance)
 278  *	@sk_err: last error
 279  *	@sk_err_soft: errors that don't cause failure but are the cause of a
 280  *		      persistent failure not just 'timed out'
 281  *	@sk_drops: raw/udp drops counter
 282  *	@sk_ack_backlog: current listen backlog
 283  *	@sk_max_ack_backlog: listen backlog set in listen()
 284  *	@sk_uid: user id of owner
 
 
 285  *	@sk_priority: %SO_PRIORITY setting
 286  *	@sk_type: socket type (%SOCK_STREAM, etc)
 287  *	@sk_protocol: which protocol this socket belongs in this network family
 
 288  *	@sk_peer_pid: &struct pid for this socket's peer
 289  *	@sk_peer_cred: %SO_PEERCRED setting
 290  *	@sk_rcvlowat: %SO_RCVLOWAT setting
 291  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
 292  *	@sk_sndtimeo: %SO_SNDTIMEO setting
 293  *	@sk_txhash: computed flow hash for use on transmit
 
 294  *	@sk_filter: socket filtering instructions
 295  *	@sk_timer: sock cleanup timer
 296  *	@sk_stamp: time stamp of last packet received
 297  *	@sk_tsflags: SO_TIMESTAMPING socket options
 
 
 
 
 
 
 298  *	@sk_tskey: counter to disambiguate concurrent tstamp requests
 299  *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
 300  *	@sk_socket: Identd and reporting IO signals
 301  *	@sk_user_data: RPC layer private data
 302  *	@sk_frag: cached page frag
 303  *	@sk_peek_off: current peek_offset value
 304  *	@sk_send_head: front of stuff to transmit
 
 305  *	@sk_security: used by security modules
 306  *	@sk_mark: generic packet mark
 307  *	@sk_cgrp_data: cgroup data for this cgroup
 308  *	@sk_memcg: this socket's memory cgroup association
 309  *	@sk_write_pending: a write to stream socket waits to start
 
 310  *	@sk_state_change: callback to indicate change in the state of the sock
 311  *	@sk_data_ready: callback to indicate there is data to be processed
 312  *	@sk_write_space: callback to indicate there is bf sending space available
 313  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
 314  *	@sk_backlog_rcv: callback to process the backlog
 
 315  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
 316  *	@sk_reuseport_cb: reuseport group container
 
 317  *	@sk_rcu: used during RCU grace period
 
 
 
 
 
 318  */
 319struct sock {
 320	/*
 321	 * Now struct inet_timewait_sock also uses sock_common, so please just
 322	 * don't add nothing before this first member (__sk_common) --acme
 323	 */
 324	struct sock_common	__sk_common;
 325#define sk_node			__sk_common.skc_node
 326#define sk_nulls_node		__sk_common.skc_nulls_node
 327#define sk_refcnt		__sk_common.skc_refcnt
 328#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
 
 
 
 329
 330#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
 331#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
 332#define sk_hash			__sk_common.skc_hash
 333#define sk_portpair		__sk_common.skc_portpair
 334#define sk_num			__sk_common.skc_num
 335#define sk_dport		__sk_common.skc_dport
 336#define sk_addrpair		__sk_common.skc_addrpair
 337#define sk_daddr		__sk_common.skc_daddr
 338#define sk_rcv_saddr		__sk_common.skc_rcv_saddr
 339#define sk_family		__sk_common.skc_family
 340#define sk_state		__sk_common.skc_state
 341#define sk_reuse		__sk_common.skc_reuse
 342#define sk_reuseport		__sk_common.skc_reuseport
 343#define sk_ipv6only		__sk_common.skc_ipv6only
 344#define sk_net_refcnt		__sk_common.skc_net_refcnt
 345#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
 346#define sk_bind_node		__sk_common.skc_bind_node
 347#define sk_prot			__sk_common.skc_prot
 348#define sk_net			__sk_common.skc_net
 349#define sk_v6_daddr		__sk_common.skc_v6_daddr
 350#define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
 351#define sk_cookie		__sk_common.skc_cookie
 352#define sk_incoming_cpu		__sk_common.skc_incoming_cpu
 353#define sk_flags		__sk_common.skc_flags
 354#define sk_rxhash		__sk_common.skc_rxhash
 355
 356	socket_lock_t		sk_lock;
 
 357	atomic_t		sk_drops;
 358	int			sk_rcvlowat;
 359	struct sk_buff_head	sk_error_queue;
 360	struct sk_buff_head	sk_receive_queue;
 361	/*
 362	 * The backlog queue is special, it is always used with
 363	 * the per-socket spinlock held and requires low latency
 364	 * access. Therefore we special case it's implementation.
 365	 * Note : rmem_alloc is in this structure to fill a hole
 366	 * on 64bit arches, not because its logically part of
 367	 * backlog.
 368	 */
 369	struct {
 370		atomic_t	rmem_alloc;
 371		int		len;
 372		struct sk_buff	*head;
 373		struct sk_buff	*tail;
 374	} sk_backlog;
 375#define sk_rmem_alloc sk_backlog.rmem_alloc
 376
 377	int			sk_forward_alloc;
 
 
 
 
 
 
 
 378#ifdef CONFIG_NET_RX_BUSY_POLL
 379	unsigned int		sk_ll_usec;
 380	/* ===== mostly read cache line ===== */
 381	unsigned int		sk_napi_id;
 
 
 382#endif
 
 383	int			sk_rcvbuf;
 384
 385	struct sk_filter __rcu	*sk_filter;
 386	union {
 387		struct socket_wq __rcu	*sk_wq;
 
 388		struct socket_wq	*sk_wq_raw;
 
 389	};
 
 
 
 
 
 
 
 
 
 
 390#ifdef CONFIG_XFRM
 391	struct xfrm_policy __rcu *sk_policy[2];
 392#endif
 393	struct dst_entry	*sk_rx_dst;
 394	struct dst_entry __rcu	*sk_dst_cache;
 
 
 
 
 
 
 
 
 
 395	atomic_t		sk_omem_alloc;
 396	int			sk_sndbuf;
 397
 398	/* ===== cache line for TX ===== */
 399	int			sk_wmem_queued;
 400	refcount_t		sk_wmem_alloc;
 401	unsigned long		sk_tsq_flags;
 402	union {
 403		struct sk_buff	*sk_send_head;
 404		struct rb_root	tcp_rtx_queue;
 405	};
 406	struct sk_buff_head	sk_write_queue;
 407	__s32			sk_peek_off;
 408	int			sk_write_pending;
 409	__u32			sk_dst_pending_confirm;
 410	u32			sk_pacing_status; /* see enum sk_pacing */
 411	long			sk_sndtimeo;
 412	struct timer_list	sk_timer;
 413	__u32			sk_priority;
 414	__u32			sk_mark;
 415	u32			sk_pacing_rate; /* bytes per second */
 416	u32			sk_max_pacing_rate;
 417	struct page_frag	sk_frag;
 
 
 
 
 
 
 
 
 
 
 
 
 
 418	netdev_features_t	sk_route_caps;
 419	netdev_features_t	sk_route_nocaps;
 420	netdev_features_t	sk_route_forced_caps;
 421	int			sk_gso_type;
 
 
 
 
 422	unsigned int		sk_gso_max_size;
 423	gfp_t			sk_allocation;
 424	__u32			sk_txhash;
 
 
 
 425
 426	/*
 427	 * Because of non atomicity rules, all
 428	 * changes are protected by socket lock.
 429	 */
 430	unsigned int		__sk_flags_offset[0];
 431#ifdef __BIG_ENDIAN_BITFIELD
 432#define SK_FL_PROTO_SHIFT  16
 433#define SK_FL_PROTO_MASK   0x00ff0000
 434
 435#define SK_FL_TYPE_SHIFT   0
 436#define SK_FL_TYPE_MASK    0x0000ffff
 437#else
 438#define SK_FL_PROTO_SHIFT  8
 439#define SK_FL_PROTO_MASK   0x0000ff00
 440
 441#define SK_FL_TYPE_SHIFT   16
 442#define SK_FL_TYPE_MASK    0xffff0000
 443#endif
 444
 445	unsigned int		sk_padding : 1,
 446				sk_kern_sock : 1,
 447				sk_no_check_tx : 1,
 448				sk_no_check_rx : 1,
 449				sk_userlocks : 4,
 450				sk_protocol  : 8,
 451				sk_type      : 16;
 452#define SK_PROTOCOL_MAX U8_MAX
 453	u16			sk_gso_max_segs;
 454	u8			sk_pacing_shift;
 455	unsigned long	        sk_lingertime;
 456	struct proto		*sk_prot_creator;
 457	rwlock_t		sk_callback_lock;
 458	int			sk_err,
 459				sk_err_soft;
 460	u32			sk_ack_backlog;
 461	u32			sk_max_ack_backlog;
 462	kuid_t			sk_uid;
 
 
 463	struct pid		*sk_peer_pid;
 464	const struct cred	*sk_peer_cred;
 465	long			sk_rcvtimeo;
 466	ktime_t			sk_stamp;
 467	u16			sk_tsflags;
 468	u8			sk_shutdown;
 469	u32			sk_tskey;
 470	atomic_t		sk_zckey;
 471	struct socket		*sk_socket;
 
 
 
 
 
 
 472	void			*sk_user_data;
 473#ifdef CONFIG_SECURITY
 474	void			*sk_security;
 475#endif
 476	struct sock_cgroup_data	sk_cgrp_data;
 477	struct mem_cgroup	*sk_memcg;
 478	void			(*sk_state_change)(struct sock *sk);
 479	void			(*sk_data_ready)(struct sock *sk);
 480	void			(*sk_write_space)(struct sock *sk);
 481	void			(*sk_error_report)(struct sock *sk);
 482	int			(*sk_backlog_rcv)(struct sock *sk,
 483						  struct sk_buff *skb);
 484	void                    (*sk_destruct)(struct sock *sk);
 485	struct sock_reuseport __rcu	*sk_reuseport_cb;
 
 
 
 486	struct rcu_head		sk_rcu;
 
 487};
 488
 489enum sk_pacing {
 490	SK_PACING_NONE		= 0,
 491	SK_PACING_NEEDED	= 1,
 492	SK_PACING_FQ		= 2,
 493};
 494
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 495#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
 496
 497#define rcu_dereference_sk_user_data(sk)	rcu_dereference(__sk_user_data((sk)))
 498#define rcu_assign_sk_user_data(sk, ptr)	rcu_assign_pointer(__sk_user_data((sk)), ptr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 499
 500/*
 501 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 502 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 503 * on a socket means that the socket will reuse everybody else's port
 504 * without looking at the other's sk_reuse value.
 505 */
 506
 507#define SK_NO_REUSE	0
 508#define SK_CAN_REUSE	1
 509#define SK_FORCE_REUSE	2
 510
 511int sk_set_peek_off(struct sock *sk, int val);
 512
 513static inline int sk_peek_offset(struct sock *sk, int flags)
 514{
 515	if (unlikely(flags & MSG_PEEK)) {
 516		return READ_ONCE(sk->sk_peek_off);
 517	}
 518
 519	return 0;
 520}
 521
 522static inline void sk_peek_offset_bwd(struct sock *sk, int val)
 523{
 524	s32 off = READ_ONCE(sk->sk_peek_off);
 525
 526	if (unlikely(off >= 0)) {
 527		off = max_t(s32, off - val, 0);
 528		WRITE_ONCE(sk->sk_peek_off, off);
 529	}
 530}
 531
 532static inline void sk_peek_offset_fwd(struct sock *sk, int val)
 533{
 534	sk_peek_offset_bwd(sk, -val);
 535}
 536
 537/*
 538 * Hashed lists helper routines
 539 */
 540static inline struct sock *sk_entry(const struct hlist_node *node)
 541{
 542	return hlist_entry(node, struct sock, sk_node);
 543}
 544
 545static inline struct sock *__sk_head(const struct hlist_head *head)
 546{
 547	return hlist_entry(head->first, struct sock, sk_node);
 548}
 549
 550static inline struct sock *sk_head(const struct hlist_head *head)
 551{
 552	return hlist_empty(head) ? NULL : __sk_head(head);
 553}
 554
 555static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
 556{
 557	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
 558}
 559
 560static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
 561{
 562	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
 563}
 564
 565static inline struct sock *sk_next(const struct sock *sk)
 566{
 567	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
 568}
 569
 570static inline struct sock *sk_nulls_next(const struct sock *sk)
 571{
 572	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
 573		hlist_nulls_entry(sk->sk_nulls_node.next,
 574				  struct sock, sk_nulls_node) :
 575		NULL;
 576}
 577
 578static inline bool sk_unhashed(const struct sock *sk)
 579{
 580	return hlist_unhashed(&sk->sk_node);
 581}
 582
 583static inline bool sk_hashed(const struct sock *sk)
 584{
 585	return !sk_unhashed(sk);
 586}
 587
 588static inline void sk_node_init(struct hlist_node *node)
 589{
 590	node->pprev = NULL;
 591}
 592
 593static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
 594{
 595	node->pprev = NULL;
 596}
 597
 598static inline void __sk_del_node(struct sock *sk)
 599{
 600	__hlist_del(&sk->sk_node);
 601}
 602
 603/* NB: equivalent to hlist_del_init_rcu */
 604static inline bool __sk_del_node_init(struct sock *sk)
 605{
 606	if (sk_hashed(sk)) {
 607		__sk_del_node(sk);
 608		sk_node_init(&sk->sk_node);
 609		return true;
 610	}
 611	return false;
 612}
 613
 614/* Grab socket reference count. This operation is valid only
 615   when sk is ALREADY grabbed f.e. it is found in hash table
 616   or a list and the lookup is made under lock preventing hash table
 617   modifications.
 618 */
 619
 620static __always_inline void sock_hold(struct sock *sk)
 621{
 622	refcount_inc(&sk->sk_refcnt);
 623}
 624
 625/* Ungrab socket in the context, which assumes that socket refcnt
 626   cannot hit zero, f.e. it is true in context of any socketcall.
 627 */
 628static __always_inline void __sock_put(struct sock *sk)
 629{
 630	refcount_dec(&sk->sk_refcnt);
 631}
 632
 633static inline bool sk_del_node_init(struct sock *sk)
 634{
 635	bool rc = __sk_del_node_init(sk);
 636
 637	if (rc) {
 638		/* paranoid for a while -acme */
 639		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 640		__sock_put(sk);
 641	}
 642	return rc;
 643}
 644#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
 645
 646static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
 647{
 648	if (sk_hashed(sk)) {
 649		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
 650		return true;
 651	}
 652	return false;
 653}
 654
 655static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
 656{
 657	bool rc = __sk_nulls_del_node_init_rcu(sk);
 658
 659	if (rc) {
 660		/* paranoid for a while -acme */
 661		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 662		__sock_put(sk);
 663	}
 664	return rc;
 665}
 666
 667static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
 668{
 669	hlist_add_head(&sk->sk_node, list);
 670}
 671
 672static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
 673{
 674	sock_hold(sk);
 675	__sk_add_node(sk, list);
 676}
 677
 678static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
 679{
 680	sock_hold(sk);
 681	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 682	    sk->sk_family == AF_INET6)
 683		hlist_add_tail_rcu(&sk->sk_node, list);
 684	else
 685		hlist_add_head_rcu(&sk->sk_node, list);
 686}
 687
 
 
 
 
 
 
 688static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 689{
 690	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
 691}
 692
 
 
 
 
 
 693static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 694{
 695	sock_hold(sk);
 696	__sk_nulls_add_node_rcu(sk, list);
 697}
 698
 699static inline void __sk_del_bind_node(struct sock *sk)
 700{
 701	__hlist_del(&sk->sk_bind_node);
 702}
 703
 704static inline void sk_add_bind_node(struct sock *sk,
 705					struct hlist_head *list)
 706{
 707	hlist_add_head(&sk->sk_bind_node, list);
 708}
 709
 710#define sk_for_each(__sk, list) \
 711	hlist_for_each_entry(__sk, list, sk_node)
 712#define sk_for_each_rcu(__sk, list) \
 713	hlist_for_each_entry_rcu(__sk, list, sk_node)
 714#define sk_nulls_for_each(__sk, node, list) \
 715	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
 716#define sk_nulls_for_each_rcu(__sk, node, list) \
 717	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
 718#define sk_for_each_from(__sk) \
 719	hlist_for_each_entry_from(__sk, sk_node)
 720#define sk_nulls_for_each_from(__sk, node) \
 721	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
 722		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
 723#define sk_for_each_safe(__sk, tmp, list) \
 724	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
 725#define sk_for_each_bound(__sk, list) \
 726	hlist_for_each_entry(__sk, list, sk_bind_node)
 727
 728/**
 729 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
 730 * @tpos:	the type * to use as a loop cursor.
 731 * @pos:	the &struct hlist_node to use as a loop cursor.
 732 * @head:	the head for your list.
 733 * @offset:	offset of hlist_node within the struct.
 734 *
 735 */
 736#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
 737	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
 738	     pos != NULL &&						       \
 739		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
 740	     pos = rcu_dereference(hlist_next_rcu(pos)))
 741
 742static inline struct user_namespace *sk_user_ns(struct sock *sk)
 743{
 744	/* Careful only use this in a context where these parameters
 745	 * can not change and must all be valid, such as recvmsg from
 746	 * userspace.
 747	 */
 748	return sk->sk_socket->file->f_cred->user_ns;
 749}
 750
 751/* Sock flags */
 752enum sock_flags {
 753	SOCK_DEAD,
 754	SOCK_DONE,
 755	SOCK_URGINLINE,
 756	SOCK_KEEPOPEN,
 757	SOCK_LINGER,
 758	SOCK_DESTROY,
 759	SOCK_BROADCAST,
 760	SOCK_TIMESTAMP,
 761	SOCK_ZAPPED,
 762	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
 763	SOCK_DBG, /* %SO_DEBUG setting */
 764	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
 765	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
 766	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 767	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
 768	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
 769	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
 770	SOCK_FASYNC, /* fasync() active */
 771	SOCK_RXQ_OVFL,
 772	SOCK_ZEROCOPY, /* buffers from userspace */
 773	SOCK_WIFI_STATUS, /* push wifi status to userspace */
 774	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
 775		     * Will use last 4 bytes of packet sent from
 776		     * user-space instead.
 777		     */
 778	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
 779	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
 780	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
 
 
 
 
 781};
 782
 783#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
 784
 785static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
 786{
 787	nsk->sk_flags = osk->sk_flags;
 788}
 789
 790static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
 791{
 792	__set_bit(flag, &sk->sk_flags);
 793}
 794
 795static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
 796{
 797	__clear_bit(flag, &sk->sk_flags);
 798}
 799
 
 
 
 
 
 
 
 
 
 800static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
 801{
 802	return test_bit(flag, &sk->sk_flags);
 803}
 804
 805#ifdef CONFIG_NET
 806extern struct static_key memalloc_socks;
 807static inline int sk_memalloc_socks(void)
 808{
 809	return static_key_false(&memalloc_socks);
 810}
 
 
 811#else
 812
 813static inline int sk_memalloc_socks(void)
 814{
 815	return 0;
 816}
 817
 
 
 818#endif
 819
 820static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
 821{
 822	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
 823}
 824
 825static inline void sk_acceptq_removed(struct sock *sk)
 826{
 827	sk->sk_ack_backlog--;
 828}
 829
 830static inline void sk_acceptq_added(struct sock *sk)
 831{
 832	sk->sk_ack_backlog++;
 833}
 834
 
 
 
 
 835static inline bool sk_acceptq_is_full(const struct sock *sk)
 836{
 837	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
 838}
 839
 840/*
 841 * Compute minimal free write space needed to queue new packets.
 842 */
 843static inline int sk_stream_min_wspace(const struct sock *sk)
 844{
 845	return sk->sk_wmem_queued >> 1;
 846}
 847
 848static inline int sk_stream_wspace(const struct sock *sk)
 849{
 850	return sk->sk_sndbuf - sk->sk_wmem_queued;
 
 
 
 
 
 
 
 
 
 
 
 851}
 852
 853void sk_stream_write_space(struct sock *sk);
 854
 855/* OOB backlog add */
 856static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 857{
 858	/* dont let skb dst not refcounted, we are going to leave rcu lock */
 859	skb_dst_force(skb);
 860
 861	if (!sk->sk_backlog.tail)
 862		sk->sk_backlog.head = skb;
 863	else
 864		sk->sk_backlog.tail->next = skb;
 865
 866	sk->sk_backlog.tail = skb;
 867	skb->next = NULL;
 868}
 869
 870/*
 871 * Take into account size of receive queue and backlog queue
 872 * Do not take into account this skb truesize,
 873 * to allow even a single big packet to come.
 874 */
 875static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
 876{
 877	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
 878
 879	return qsize > limit;
 880}
 881
 882/* The per-socket spinlock must be held here. */
 883static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
 884					      unsigned int limit)
 885{
 886	if (sk_rcvqueues_full(sk, limit))
 887		return -ENOBUFS;
 888
 889	/*
 890	 * If the skb was allocated from pfmemalloc reserves, only
 891	 * allow SOCK_MEMALLOC sockets to use it as this socket is
 892	 * helping free memory
 893	 */
 894	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
 895		return -ENOMEM;
 896
 897	__sk_add_backlog(sk, skb);
 898	sk->sk_backlog.len += skb->truesize;
 899	return 0;
 900}
 901
 902int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 903
 
 
 
 904static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 905{
 906	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
 907		return __sk_backlog_rcv(sk, skb);
 908
 909	return sk->sk_backlog_rcv(sk, skb);
 
 
 
 910}
 911
 912static inline void sk_incoming_cpu_update(struct sock *sk)
 913{
 914	int cpu = raw_smp_processor_id();
 915
 916	if (unlikely(sk->sk_incoming_cpu != cpu))
 917		sk->sk_incoming_cpu = cpu;
 918}
 919
 920static inline void sock_rps_record_flow_hash(__u32 hash)
 921{
 922#ifdef CONFIG_RPS
 923	struct rps_sock_flow_table *sock_flow_table;
 924
 925	rcu_read_lock();
 926	sock_flow_table = rcu_dereference(rps_sock_flow_table);
 927	rps_record_sock_flow(sock_flow_table, hash);
 928	rcu_read_unlock();
 929#endif
 930}
 931
 932static inline void sock_rps_record_flow(const struct sock *sk)
 933{
 934#ifdef CONFIG_RPS
 935	if (static_key_false(&rfs_needed)) {
 936		/* Reading sk->sk_rxhash might incur an expensive cache line
 937		 * miss.
 938		 *
 939		 * TCP_ESTABLISHED does cover almost all states where RFS
 940		 * might be useful, and is cheaper [1] than testing :
 941		 *	IPv4: inet_sk(sk)->inet_daddr
 942		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
 943		 * OR	an additional socket flag
 944		 * [1] : sk_state and sk_prot are in the same cache line.
 945		 */
 946		if (sk->sk_state == TCP_ESTABLISHED)
 947			sock_rps_record_flow_hash(sk->sk_rxhash);
 948	}
 949#endif
 950}
 951
 952static inline void sock_rps_save_rxhash(struct sock *sk,
 953					const struct sk_buff *skb)
 954{
 955#ifdef CONFIG_RPS
 956	if (unlikely(sk->sk_rxhash != skb->hash))
 957		sk->sk_rxhash = skb->hash;
 
 
 
 958#endif
 959}
 960
 961static inline void sock_rps_reset_rxhash(struct sock *sk)
 962{
 963#ifdef CONFIG_RPS
 964	sk->sk_rxhash = 0;
 
 965#endif
 966}
 967
 968#define sk_wait_event(__sk, __timeo, __condition, __wait)		\
 969	({	int __rc;						\
 970		release_sock(__sk);					\
 971		__rc = __condition;					\
 972		if (!__rc) {						\
 973			*(__timeo) = wait_woken(__wait,			\
 974						TASK_INTERRUPTIBLE,	\
 975						*(__timeo));		\
 976		}							\
 977		sched_annotate_sleep();					\
 978		lock_sock(__sk);					\
 979		__rc = __condition;					\
 980		__rc;							\
 981	})
 982
 983int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
 984int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
 985void sk_stream_wait_close(struct sock *sk, long timeo_p);
 986int sk_stream_error(struct sock *sk, int flags, int err);
 987void sk_stream_kill_queues(struct sock *sk);
 988void sk_set_memalloc(struct sock *sk);
 989void sk_clear_memalloc(struct sock *sk);
 990
 991void __sk_flush_backlog(struct sock *sk);
 992
 993static inline bool sk_flush_backlog(struct sock *sk)
 994{
 995	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
 996		__sk_flush_backlog(sk);
 997		return true;
 998	}
 999	return false;
1000}
1001
1002int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1003
1004struct request_sock_ops;
1005struct timewait_sock_ops;
1006struct inet_hashinfo;
1007struct raw_hashinfo;
1008struct smc_hashinfo;
1009struct module;
 
1010
1011/*
1012 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1013 * un-modified. Special care is taken when initializing object to zero.
1014 */
1015static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1016{
1017	if (offsetof(struct sock, sk_node.next) != 0)
1018		memset(sk, 0, offsetof(struct sock, sk_node.next));
1019	memset(&sk->sk_node.pprev, 0,
1020	       size - offsetof(struct sock, sk_node.pprev));
1021}
1022
1023/* Networking protocol blocks we attach to sockets.
1024 * socket layer -> transport layer interface
1025 */
1026struct proto {
1027	void			(*close)(struct sock *sk,
1028					long timeout);
1029	int			(*pre_connect)(struct sock *sk,
1030					struct sockaddr *uaddr,
1031					int addr_len);
1032	int			(*connect)(struct sock *sk,
1033					struct sockaddr *uaddr,
1034					int addr_len);
1035	int			(*disconnect)(struct sock *sk, int flags);
1036
1037	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1038					  bool kern);
1039
1040	int			(*ioctl)(struct sock *sk, int cmd,
1041					 unsigned long arg);
1042	int			(*init)(struct sock *sk);
1043	void			(*destroy)(struct sock *sk);
1044	void			(*shutdown)(struct sock *sk, int how);
1045	int			(*setsockopt)(struct sock *sk, int level,
1046					int optname, char __user *optval,
1047					unsigned int optlen);
1048	int			(*getsockopt)(struct sock *sk, int level,
1049					int optname, char __user *optval,
1050					int __user *option);
1051	void			(*keepalive)(struct sock *sk, int valbool);
1052#ifdef CONFIG_COMPAT
1053	int			(*compat_setsockopt)(struct sock *sk,
1054					int level,
1055					int optname, char __user *optval,
1056					unsigned int optlen);
1057	int			(*compat_getsockopt)(struct sock *sk,
1058					int level,
1059					int optname, char __user *optval,
1060					int __user *option);
1061	int			(*compat_ioctl)(struct sock *sk,
1062					unsigned int cmd, unsigned long arg);
1063#endif
1064	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1065					   size_t len);
1066	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1067					   size_t len, int noblock, int flags,
1068					   int *addr_len);
1069	int			(*sendpage)(struct sock *sk, struct page *page,
1070					int offset, size_t size, int flags);
1071	int			(*bind)(struct sock *sk,
1072					struct sockaddr *uaddr, int addr_len);
 
 
1073
1074	int			(*backlog_rcv) (struct sock *sk,
1075						struct sk_buff *skb);
 
 
1076
1077	void		(*release_cb)(struct sock *sk);
1078
1079	/* Keeping track of sk's, looking them up, and port selection methods. */
1080	int			(*hash)(struct sock *sk);
1081	void			(*unhash)(struct sock *sk);
1082	void			(*rehash)(struct sock *sk);
1083	int			(*get_port)(struct sock *sk, unsigned short snum);
 
 
 
 
 
 
1084
1085	/* Keeping track of sockets in use */
1086#ifdef CONFIG_PROC_FS
1087	unsigned int		inuse_idx;
1088#endif
1089
1090	bool			(*stream_memory_free)(const struct sock *sk);
1091	bool			(*stream_memory_read)(const struct sock *sk);
 
 
 
 
1092	/* Memory pressure */
1093	void			(*enter_memory_pressure)(struct sock *sk);
1094	void			(*leave_memory_pressure)(struct sock *sk);
1095	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
 
1096	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
 
1097	/*
1098	 * Pressure flag: try to collapse.
1099	 * Technical note: it is used by multiple contexts non atomically.
 
1100	 * All the __sk_mem_schedule() is of this nature: accounting
1101	 * is strict, actions are advisory and have some latency.
1102	 */
1103	unsigned long		*memory_pressure;
1104	long			*sysctl_mem;
1105
1106	int			*sysctl_wmem;
1107	int			*sysctl_rmem;
1108	u32			sysctl_wmem_offset;
1109	u32			sysctl_rmem_offset;
1110
1111	int			max_header;
1112	bool			no_autobind;
1113
1114	struct kmem_cache	*slab;
1115	unsigned int		obj_size;
 
1116	slab_flags_t		slab_flags;
1117	unsigned int		useroffset;	/* Usercopy region offset */
1118	unsigned int		usersize;	/* Usercopy region size */
1119
1120	struct percpu_counter	*orphan_count;
1121
1122	struct request_sock_ops	*rsk_prot;
1123	struct timewait_sock_ops *twsk_prot;
1124
1125	union {
1126		struct inet_hashinfo	*hashinfo;
1127		struct udp_table	*udp_table;
1128		struct raw_hashinfo	*raw_hash;
1129		struct smc_hashinfo	*smc_hash;
1130	} h;
1131
1132	struct module		*owner;
1133
1134	char			name[32];
1135
1136	struct list_head	node;
1137#ifdef SOCK_REFCNT_DEBUG
1138	atomic_t		socks;
1139#endif
1140	int			(*diag_destroy)(struct sock *sk, int err);
1141} __randomize_layout;
1142
1143int proto_register(struct proto *prot, int alloc_slab);
1144void proto_unregister(struct proto *prot);
1145int sock_load_diag_module(int family, int protocol);
1146
1147#ifdef SOCK_REFCNT_DEBUG
1148static inline void sk_refcnt_debug_inc(struct sock *sk)
1149{
1150	atomic_inc(&sk->sk_prot->socks);
1151}
1152
1153static inline void sk_refcnt_debug_dec(struct sock *sk)
1154{
1155	atomic_dec(&sk->sk_prot->socks);
1156	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1157	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
 
 
1158}
1159
1160static inline void sk_refcnt_debug_release(const struct sock *sk)
1161{
1162	if (refcount_read(&sk->sk_refcnt) != 1)
1163		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1164		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
 
 
 
1165}
1166#else /* SOCK_REFCNT_DEBUG */
1167#define sk_refcnt_debug_inc(sk) do { } while (0)
1168#define sk_refcnt_debug_dec(sk) do { } while (0)
1169#define sk_refcnt_debug_release(sk) do { } while (0)
1170#endif /* SOCK_REFCNT_DEBUG */
1171
1172static inline bool sk_stream_memory_free(const struct sock *sk)
1173{
1174	if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1175		return false;
1176
1177	return sk->sk_prot->stream_memory_free ?
1178		sk->sk_prot->stream_memory_free(sk) : true;
 
 
1179}
1180
1181static inline bool sk_stream_is_writeable(const struct sock *sk)
1182{
1183	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1184	       sk_stream_memory_free(sk);
1185}
1186
1187static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1188					    struct cgroup *ancestor)
1189{
1190#ifdef CONFIG_SOCK_CGROUP_DATA
1191	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1192				    ancestor);
1193#else
1194	return -ENOTSUPP;
1195#endif
1196}
1197
1198static inline bool sk_has_memory_pressure(const struct sock *sk)
1199{
1200	return sk->sk_prot->memory_pressure != NULL;
1201}
1202
 
 
 
 
 
 
1203static inline bool sk_under_memory_pressure(const struct sock *sk)
1204{
1205	if (!sk->sk_prot->memory_pressure)
1206		return false;
1207
1208	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1209	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1210		return true;
1211
1212	return !!*sk->sk_prot->memory_pressure;
1213}
1214
1215static inline long
1216sk_memory_allocated(const struct sock *sk)
1217{
1218	return atomic_long_read(sk->sk_prot->memory_allocated);
1219}
1220
1221static inline long
1222sk_memory_allocated_add(struct sock *sk, int amt)
1223{
1224	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
 
 
 
 
 
 
 
 
 
 
 
 
1225}
1226
1227static inline void
1228sk_memory_allocated_sub(struct sock *sk, int amt)
1229{
1230	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
 
 
 
 
 
1231}
1232
 
 
 
 
 
 
 
 
 
 
 
 
 
1233static inline void sk_sockets_allocated_dec(struct sock *sk)
1234{
1235	percpu_counter_dec(sk->sk_prot->sockets_allocated);
 
1236}
1237
1238static inline void sk_sockets_allocated_inc(struct sock *sk)
1239{
1240	percpu_counter_inc(sk->sk_prot->sockets_allocated);
 
1241}
1242
1243static inline int
1244sk_sockets_allocated_read_positive(struct sock *sk)
1245{
1246	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1247}
1248
1249static inline int
1250proto_sockets_allocated_sum_positive(struct proto *prot)
1251{
1252	return percpu_counter_sum_positive(prot->sockets_allocated);
1253}
1254
1255static inline long
1256proto_memory_allocated(struct proto *prot)
1257{
1258	return atomic_long_read(prot->memory_allocated);
1259}
1260
1261static inline bool
1262proto_memory_pressure(struct proto *prot)
1263{
1264	if (!prot->memory_pressure)
1265		return false;
1266	return !!*prot->memory_pressure;
1267}
1268
1269
1270#ifdef CONFIG_PROC_FS
1271/* Called with local bh disabled */
1272void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1273int sock_prot_inuse_get(struct net *net, struct proto *proto);
1274int sock_inuse_get(struct net *net);
1275#else
1276static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1277		int inc)
 
 
 
 
1278{
1279}
1280#endif
1281
1282
1283/* With per-bucket locks this operation is not-atomic, so that
1284 * this version is not worse.
1285 */
1286static inline int __sk_prot_rehash(struct sock *sk)
1287{
1288	sk->sk_prot->unhash(sk);
1289	return sk->sk_prot->hash(sk);
1290}
1291
1292/* About 10 seconds */
1293#define SOCK_DESTROY_TIME (10*HZ)
1294
1295/* Sockets 0-1023 can't be bound to unless you are superuser */
1296#define PROT_SOCK	1024
1297
1298#define SHUTDOWN_MASK	3
1299#define RCV_SHUTDOWN	1
1300#define SEND_SHUTDOWN	2
1301
1302#define SOCK_SNDBUF_LOCK	1
1303#define SOCK_RCVBUF_LOCK	2
1304#define SOCK_BINDADDR_LOCK	4
1305#define SOCK_BINDPORT_LOCK	8
1306
1307struct socket_alloc {
1308	struct socket socket;
1309	struct inode vfs_inode;
1310};
1311
1312static inline struct socket *SOCKET_I(struct inode *inode)
1313{
1314	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1315}
1316
1317static inline struct inode *SOCK_INODE(struct socket *socket)
1318{
1319	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1320}
1321
1322/*
1323 * Functions for memory accounting
1324 */
1325int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1326int __sk_mem_schedule(struct sock *sk, int size, int kind);
1327void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1328void __sk_mem_reclaim(struct sock *sk, int amount);
1329
1330/* We used to have PAGE_SIZE here, but systems with 64KB pages
1331 * do not necessarily have 16x time more memory than 4KB ones.
1332 */
1333#define SK_MEM_QUANTUM 4096
1334#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1335#define SK_MEM_SEND	0
1336#define SK_MEM_RECV	1
1337
1338/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1339static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1340{
1341	long val = sk->sk_prot->sysctl_mem[index];
1342
1343#if PAGE_SIZE > SK_MEM_QUANTUM
1344	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1345#elif PAGE_SIZE < SK_MEM_QUANTUM
1346	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1347#endif
1348	return val;
1349}
1350
1351static inline int sk_mem_pages(int amt)
1352{
1353	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1354}
1355
1356static inline bool sk_has_account(struct sock *sk)
1357{
1358	/* return true if protocol supports memory accounting */
1359	return !!sk->sk_prot->memory_allocated;
1360}
1361
1362static inline bool sk_wmem_schedule(struct sock *sk, int size)
1363{
 
 
1364	if (!sk_has_account(sk))
1365		return true;
1366	return size <= sk->sk_forward_alloc ||
1367		__sk_mem_schedule(sk, size, SK_MEM_SEND);
1368}
1369
1370static inline bool
1371sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1372{
 
 
1373	if (!sk_has_account(sk))
1374		return true;
1375	return size<= sk->sk_forward_alloc ||
1376		__sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1377		skb_pfmemalloc(skb);
1378}
1379
 
 
 
 
 
 
 
 
 
 
 
 
 
1380static inline void sk_mem_reclaim(struct sock *sk)
1381{
 
 
1382	if (!sk_has_account(sk))
1383		return;
1384	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1385		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
 
 
 
1386}
1387
1388static inline void sk_mem_reclaim_partial(struct sock *sk)
1389{
1390	if (!sk_has_account(sk))
1391		return;
1392	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1393		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1394}
1395
1396static inline void sk_mem_charge(struct sock *sk, int size)
1397{
1398	if (!sk_has_account(sk))
1399		return;
1400	sk->sk_forward_alloc -= size;
1401}
1402
1403static inline void sk_mem_uncharge(struct sock *sk, int size)
1404{
1405	if (!sk_has_account(sk))
1406		return;
1407	sk->sk_forward_alloc += size;
1408
1409	/* Avoid a possible overflow.
1410	 * TCP send queues can make this happen, if sk_mem_reclaim()
1411	 * is not called and more than 2 GBytes are released at once.
1412	 *
1413	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1414	 * no need to hold that much forward allocation anyway.
1415	 */
1416	if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1417		__sk_mem_reclaim(sk, 1 << 20);
1418}
1419
1420static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1421{
1422	sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1423	sk->sk_wmem_queued -= skb->truesize;
1424	sk_mem_uncharge(sk, skb->truesize);
1425	__kfree_skb(skb);
1426}
1427
1428static inline void sock_release_ownership(struct sock *sk)
1429{
1430	if (sk->sk_lock.owned) {
1431		sk->sk_lock.owned = 0;
1432
1433		/* The sk_lock has mutex_unlock() semantics: */
1434		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1435	}
1436}
1437
1438/*
1439 * Macro so as to not evaluate some arguments when
1440 * lockdep is not enabled.
1441 *
1442 * Mark both the sk_lock and the sk_lock.slock as a
1443 * per-address-family lock class.
1444 */
1445#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1446do {									\
1447	sk->sk_lock.owned = 0;						\
1448	init_waitqueue_head(&sk->sk_lock.wq);				\
1449	spin_lock_init(&(sk)->sk_lock.slock);				\
1450	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1451			sizeof((sk)->sk_lock));				\
1452	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1453				(skey), (sname));				\
1454	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1455} while (0)
1456
1457#ifdef CONFIG_LOCKDEP
1458static inline bool lockdep_sock_is_held(const struct sock *sk)
1459{
1460	return lockdep_is_held(&sk->sk_lock) ||
1461	       lockdep_is_held(&sk->sk_lock.slock);
1462}
1463#endif
1464
1465void lock_sock_nested(struct sock *sk, int subclass);
1466
1467static inline void lock_sock(struct sock *sk)
1468{
1469	lock_sock_nested(sk, 0);
1470}
1471
 
 
1472void release_sock(struct sock *sk);
1473
1474/* BH context may only use the following locking interface. */
1475#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1476#define bh_lock_sock_nested(__sk) \
1477				spin_lock_nested(&((__sk)->sk_lock.slock), \
1478				SINGLE_DEPTH_NESTING)
1479#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1480
1481bool lock_sock_fast(struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1482/**
1483 * unlock_sock_fast - complement of lock_sock_fast
1484 * @sk: socket
1485 * @slow: slow mode
1486 *
1487 * fast unlock socket for user context.
1488 * If slow mode is on, we call regular release_sock()
1489 */
1490static inline void unlock_sock_fast(struct sock *sk, bool slow)
 
1491{
1492	if (slow)
1493		release_sock(sk);
1494	else
 
 
1495		spin_unlock_bh(&sk->sk_lock.slock);
 
1496}
1497
 
 
 
 
 
1498/* Used by processes to "lock" a socket state, so that
1499 * interrupts and bottom half handlers won't change it
1500 * from under us. It essentially blocks any incoming
1501 * packets, so that we won't get any new data or any
1502 * packets that change the state of the socket.
1503 *
1504 * While locked, BH processing will add new packets to
1505 * the backlog queue.  This queue is processed by the
1506 * owner of the socket lock right before it is released.
1507 *
1508 * Since ~2.3.5 it is also exclusive sleep lock serializing
1509 * accesses from user process context.
1510 */
1511
1512static inline void sock_owned_by_me(const struct sock *sk)
1513{
1514#ifdef CONFIG_LOCKDEP
1515	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1516#endif
1517}
1518
 
 
 
 
 
 
 
1519static inline bool sock_owned_by_user(const struct sock *sk)
1520{
1521	sock_owned_by_me(sk);
1522	return sk->sk_lock.owned;
1523}
1524
1525static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1526{
1527	return sk->sk_lock.owned;
1528}
1529
 
 
 
 
 
 
 
 
 
1530/* no reclassification while locks are held */
1531static inline bool sock_allow_reclassification(const struct sock *csk)
1532{
1533	struct sock *sk = (struct sock *)csk;
1534
1535	return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
 
1536}
1537
1538struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1539		      struct proto *prot, int kern);
1540void sk_free(struct sock *sk);
1541void sk_destruct(struct sock *sk);
1542struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1543void sk_free_unlock_clone(struct sock *sk);
1544
1545struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1546			     gfp_t priority);
1547void __sock_wfree(struct sk_buff *skb);
1548void sock_wfree(struct sk_buff *skb);
1549struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1550			     gfp_t priority);
1551void skb_orphan_partial(struct sk_buff *skb);
1552void sock_rfree(struct sk_buff *skb);
1553void sock_efree(struct sk_buff *skb);
1554#ifdef CONFIG_INET
1555void sock_edemux(struct sk_buff *skb);
 
1556#else
1557#define sock_edemux sock_efree
1558#endif
1559
 
 
1560int sock_setsockopt(struct socket *sock, int level, int op,
1561		    char __user *optval, unsigned int optlen);
1562
1563int sock_getsockopt(struct socket *sock, int level, int op,
1564		    char __user *optval, int __user *optlen);
1565struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1566				    int noblock, int *errcode);
 
 
 
 
1567struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1568				     unsigned long data_len, int noblock,
1569				     int *errcode, int max_page_order);
 
 
 
 
 
 
 
 
1570void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1571void sock_kfree_s(struct sock *sk, void *mem, int size);
1572void sock_kzfree_s(struct sock *sk, void *mem, int size);
1573void sk_send_sigurg(struct sock *sk);
1574
 
 
 
 
 
 
 
1575struct sockcm_cookie {
 
1576	u32 mark;
1577	u16 tsflags;
1578};
1579
1580int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
 
 
 
 
 
 
 
 
1581		     struct sockcm_cookie *sockc);
1582int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1583		   struct sockcm_cookie *sockc);
1584
1585/*
1586 * Functions to fill in entries in struct proto_ops when a protocol
1587 * does not implement a particular function.
1588 */
1589int sock_no_bind(struct socket *, struct sockaddr *, int);
1590int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1591int sock_no_socketpair(struct socket *, struct socket *);
1592int sock_no_accept(struct socket *, struct socket *, int, bool);
1593int sock_no_getname(struct socket *, struct sockaddr *, int);
1594__poll_t sock_no_poll(struct file *, struct socket *,
1595			  struct poll_table_struct *);
1596int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1597int sock_no_listen(struct socket *, int);
1598int sock_no_shutdown(struct socket *, int);
1599int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1600int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1601int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1602int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1603int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1604int sock_no_mmap(struct file *file, struct socket *sock,
1605		 struct vm_area_struct *vma);
1606ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1607			 size_t size, int flags);
1608ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1609				int offset, size_t size, int flags);
1610
1611/*
1612 * Functions to fill in entries in struct proto_ops when a protocol
1613 * uses the inet style.
1614 */
1615int sock_common_getsockopt(struct socket *sock, int level, int optname,
1616				  char __user *optval, int __user *optlen);
1617int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1618			int flags);
1619int sock_common_setsockopt(struct socket *sock, int level, int optname,
1620				  char __user *optval, unsigned int optlen);
1621int compat_sock_common_getsockopt(struct socket *sock, int level,
1622		int optname, char __user *optval, int __user *optlen);
1623int compat_sock_common_setsockopt(struct socket *sock, int level,
1624		int optname, char __user *optval, unsigned int optlen);
1625
1626void sk_common_release(struct sock *sk);
1627
1628/*
1629 *	Default socket callbacks and setup code
1630 */
1631
1632/* Initialise core socket variables */
 
 
 
 
 
1633void sock_init_data(struct socket *sock, struct sock *sk);
1634
1635/*
1636 * Socket reference counting postulates.
1637 *
1638 * * Each user of socket SHOULD hold a reference count.
1639 * * Each access point to socket (an hash table bucket, reference from a list,
1640 *   running timer, skb in flight MUST hold a reference count.
1641 * * When reference count hits 0, it means it will never increase back.
1642 * * When reference count hits 0, it means that no references from
1643 *   outside exist to this socket and current process on current CPU
1644 *   is last user and may/should destroy this socket.
1645 * * sk_free is called from any context: process, BH, IRQ. When
1646 *   it is called, socket has no references from outside -> sk_free
1647 *   may release descendant resources allocated by the socket, but
1648 *   to the time when it is called, socket is NOT referenced by any
1649 *   hash tables, lists etc.
1650 * * Packets, delivered from outside (from network or from another process)
1651 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1652 *   when they sit in queue. Otherwise, packets will leak to hole, when
1653 *   socket is looked up by one cpu and unhasing is made by another CPU.
1654 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1655 *   (leak to backlog). Packet socket does all the processing inside
1656 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1657 *   use separate SMP lock, so that they are prone too.
1658 */
1659
1660/* Ungrab socket and destroy it, if it was the last reference. */
1661static inline void sock_put(struct sock *sk)
1662{
1663	if (refcount_dec_and_test(&sk->sk_refcnt))
1664		sk_free(sk);
1665}
1666/* Generic version of sock_put(), dealing with all sockets
1667 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1668 */
1669void sock_gen_put(struct sock *sk);
1670
1671int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1672		     unsigned int trim_cap, bool refcounted);
1673static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1674				 const int nested)
1675{
1676	return __sk_receive_skb(sk, skb, nested, 1, true);
1677}
1678
1679static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1680{
1681	sk->sk_tx_queue_mapping = tx_queue;
 
 
 
 
 
 
1682}
1683
 
 
1684static inline void sk_tx_queue_clear(struct sock *sk)
1685{
1686	sk->sk_tx_queue_mapping = -1;
 
 
 
1687}
1688
1689static inline int sk_tx_queue_get(const struct sock *sk)
1690{
1691	return sk ? sk->sk_tx_queue_mapping : -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1692}
1693
1694static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1695{
1696	sk_tx_queue_clear(sk);
1697	sk->sk_socket = sock;
1698}
1699
1700static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1701{
1702	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1703	return &rcu_dereference_raw(sk->sk_wq)->wait;
1704}
1705/* Detach socket from process context.
1706 * Announce socket dead, detach it from wait queue and inode.
1707 * Note that parent inode held reference count on this struct sock,
1708 * we do not release it in this function, because protocol
1709 * probably wants some additional cleanups or even continuing
1710 * to work with this socket (TCP).
1711 */
1712static inline void sock_orphan(struct sock *sk)
1713{
1714	write_lock_bh(&sk->sk_callback_lock);
1715	sock_set_flag(sk, SOCK_DEAD);
1716	sk_set_socket(sk, NULL);
1717	sk->sk_wq  = NULL;
1718	write_unlock_bh(&sk->sk_callback_lock);
1719}
1720
1721static inline void sock_graft(struct sock *sk, struct socket *parent)
1722{
1723	WARN_ON(parent->sk);
1724	write_lock_bh(&sk->sk_callback_lock);
1725	sk->sk_wq = parent->wq;
1726	parent->sk = sk;
1727	sk_set_socket(sk, parent);
1728	sk->sk_uid = SOCK_INODE(parent)->i_uid;
1729	security_sock_graft(sk, parent);
1730	write_unlock_bh(&sk->sk_callback_lock);
1731}
1732
1733kuid_t sock_i_uid(struct sock *sk);
 
1734unsigned long sock_i_ino(struct sock *sk);
1735
1736static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1737{
1738	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1739}
1740
1741static inline u32 net_tx_rndhash(void)
1742{
1743	u32 v = prandom_u32();
1744
1745	return v ?: 1;
1746}
1747
1748static inline void sk_set_txhash(struct sock *sk)
1749{
1750	sk->sk_txhash = net_tx_rndhash();
 
1751}
1752
1753static inline void sk_rethink_txhash(struct sock *sk)
1754{
1755	if (sk->sk_txhash)
1756		sk_set_txhash(sk);
 
 
 
1757}
1758
1759static inline struct dst_entry *
1760__sk_dst_get(struct sock *sk)
1761{
1762	return rcu_dereference_check(sk->sk_dst_cache,
1763				     lockdep_sock_is_held(sk));
1764}
1765
1766static inline struct dst_entry *
1767sk_dst_get(struct sock *sk)
1768{
1769	struct dst_entry *dst;
1770
1771	rcu_read_lock();
1772	dst = rcu_dereference(sk->sk_dst_cache);
1773	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1774		dst = NULL;
1775	rcu_read_unlock();
1776	return dst;
1777}
1778
1779static inline void dst_negative_advice(struct sock *sk)
1780{
1781	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1782
1783	sk_rethink_txhash(sk);
1784
1785	if (dst && dst->ops->negative_advice) {
1786		ndst = dst->ops->negative_advice(dst);
 
1787
1788		if (ndst != dst) {
1789			rcu_assign_pointer(sk->sk_dst_cache, ndst);
1790			sk_tx_queue_clear(sk);
1791			sk->sk_dst_pending_confirm = 0;
1792		}
1793	}
1794}
1795
1796static inline void
1797__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1798{
1799	struct dst_entry *old_dst;
1800
1801	sk_tx_queue_clear(sk);
1802	sk->sk_dst_pending_confirm = 0;
1803	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
1804					    lockdep_sock_is_held(sk));
1805	rcu_assign_pointer(sk->sk_dst_cache, dst);
1806	dst_release(old_dst);
1807}
1808
1809static inline void
1810sk_dst_set(struct sock *sk, struct dst_entry *dst)
1811{
1812	struct dst_entry *old_dst;
1813
1814	sk_tx_queue_clear(sk);
1815	sk->sk_dst_pending_confirm = 0;
1816	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1817	dst_release(old_dst);
1818}
1819
1820static inline void
1821__sk_dst_reset(struct sock *sk)
1822{
1823	__sk_dst_set(sk, NULL);
1824}
1825
1826static inline void
1827sk_dst_reset(struct sock *sk)
1828{
1829	sk_dst_set(sk, NULL);
1830}
1831
1832struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1833
1834struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1835
1836static inline void sk_dst_confirm(struct sock *sk)
1837{
1838	if (!sk->sk_dst_pending_confirm)
1839		sk->sk_dst_pending_confirm = 1;
1840}
1841
1842static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
1843{
1844	if (skb_get_dst_pending_confirm(skb)) {
1845		struct sock *sk = skb->sk;
1846		unsigned long now = jiffies;
1847
1848		/* avoid dirtying neighbour */
1849		if (n->confirmed != now)
1850			n->confirmed = now;
1851		if (sk && sk->sk_dst_pending_confirm)
1852			sk->sk_dst_pending_confirm = 0;
1853	}
1854}
1855
1856bool sk_mc_loop(struct sock *sk);
1857
1858static inline bool sk_can_gso(const struct sock *sk)
1859{
1860	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1861}
1862
1863void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1864
1865static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1866{
1867	sk->sk_route_nocaps |= flags;
1868	sk->sk_route_caps &= ~flags;
1869}
1870
1871static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1872					   struct iov_iter *from, char *to,
1873					   int copy, int offset)
1874{
1875	if (skb->ip_summed == CHECKSUM_NONE) {
1876		__wsum csum = 0;
1877		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
1878			return -EFAULT;
1879		skb->csum = csum_block_add(skb->csum, csum, offset);
1880	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1881		if (!copy_from_iter_full_nocache(to, copy, from))
1882			return -EFAULT;
1883	} else if (!copy_from_iter_full(to, copy, from))
1884		return -EFAULT;
1885
1886	return 0;
1887}
1888
1889static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1890				       struct iov_iter *from, int copy)
1891{
1892	int err, offset = skb->len;
1893
1894	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1895				       copy, offset);
1896	if (err)
1897		__skb_trim(skb, offset);
1898
1899	return err;
1900}
1901
1902static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1903					   struct sk_buff *skb,
1904					   struct page *page,
1905					   int off, int copy)
1906{
1907	int err;
1908
1909	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1910				       copy, skb->len);
1911	if (err)
1912		return err;
1913
1914	skb->len	     += copy;
1915	skb->data_len	     += copy;
1916	skb->truesize	     += copy;
1917	sk->sk_wmem_queued   += copy;
1918	sk_mem_charge(sk, copy);
1919	return 0;
1920}
1921
1922/**
1923 * sk_wmem_alloc_get - returns write allocations
1924 * @sk: socket
1925 *
1926 * Returns sk_wmem_alloc minus initial offset of one
1927 */
1928static inline int sk_wmem_alloc_get(const struct sock *sk)
1929{
1930	return refcount_read(&sk->sk_wmem_alloc) - 1;
1931}
1932
1933/**
1934 * sk_rmem_alloc_get - returns read allocations
1935 * @sk: socket
1936 *
1937 * Returns sk_rmem_alloc
1938 */
1939static inline int sk_rmem_alloc_get(const struct sock *sk)
1940{
1941	return atomic_read(&sk->sk_rmem_alloc);
1942}
1943
1944/**
1945 * sk_has_allocations - check if allocations are outstanding
1946 * @sk: socket
1947 *
1948 * Returns true if socket has write or read allocations
1949 */
1950static inline bool sk_has_allocations(const struct sock *sk)
1951{
1952	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1953}
1954
1955/**
1956 * skwq_has_sleeper - check if there are any waiting processes
1957 * @wq: struct socket_wq
1958 *
1959 * Returns true if socket_wq has waiting processes
1960 *
1961 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
1962 * barrier call. They were added due to the race found within the tcp code.
1963 *
1964 * Consider following tcp code paths::
1965 *
1966 *   CPU1                CPU2
1967 *   sys_select          receive packet
1968 *   ...                 ...
1969 *   __add_wait_queue    update tp->rcv_nxt
1970 *   ...                 ...
1971 *   tp->rcv_nxt check   sock_def_readable
1972 *   ...                 {
1973 *   schedule               rcu_read_lock();
1974 *                          wq = rcu_dereference(sk->sk_wq);
1975 *                          if (wq && waitqueue_active(&wq->wait))
1976 *                              wake_up_interruptible(&wq->wait)
1977 *                          ...
1978 *                       }
1979 *
1980 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1981 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
1982 * could then endup calling schedule and sleep forever if there are no more
1983 * data on the socket.
1984 *
1985 */
1986static inline bool skwq_has_sleeper(struct socket_wq *wq)
1987{
1988	return wq && wq_has_sleeper(&wq->wait);
1989}
1990
1991/**
1992 * sock_poll_wait - place memory barrier behind the poll_wait call.
1993 * @filp:           file
1994 * @wait_address:   socket wait queue
1995 * @p:              poll_table
1996 *
1997 * See the comments in the wq_has_sleeper function.
1998 */
1999static inline void sock_poll_wait(struct file *filp,
2000		wait_queue_head_t *wait_address, poll_table *p)
2001{
2002	if (!poll_does_not_wait(p) && wait_address) {
2003		poll_wait(filp, wait_address, p);
2004		/* We need to be sure we are in sync with the
2005		 * socket flags modification.
2006		 *
2007		 * This memory barrier is paired in the wq_has_sleeper.
2008		 */
2009		smp_mb();
2010	}
2011}
2012
2013static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2014{
2015	if (sk->sk_txhash) {
 
 
 
2016		skb->l4_hash = 1;
2017		skb->hash = sk->sk_txhash;
2018	}
2019}
2020
2021void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2022
2023/*
2024 *	Queue a received datagram if it will fit. Stream and sequenced
2025 *	protocols can't normally use this as they need to fit buffers in
2026 *	and play with them.
2027 *
2028 *	Inlined as it's very short and called for pretty much every
2029 *	packet ever received.
2030 */
2031static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2032{
2033	skb_orphan(skb);
2034	skb->sk = sk;
2035	skb->destructor = sock_rfree;
2036	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2037	sk_mem_charge(sk, skb->truesize);
2038}
2039
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2040void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2041		    unsigned long expires);
2042
2043void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2044
 
 
2045int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2046			struct sk_buff *skb, unsigned int flags,
2047			void (*destructor)(struct sock *sk,
2048					   struct sk_buff *skb));
2049int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2050int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 
 
 
 
 
 
 
2051
2052int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2053struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2054
2055/*
2056 *	Recover an error report and clear atomically
2057 */
2058
2059static inline int sock_error(struct sock *sk)
2060{
2061	int err;
2062	if (likely(!sk->sk_err))
 
 
 
 
2063		return 0;
 
2064	err = xchg(&sk->sk_err, 0);
2065	return -err;
2066}
2067
 
 
2068static inline unsigned long sock_wspace(struct sock *sk)
2069{
2070	int amt = 0;
2071
2072	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2073		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2074		if (amt < 0)
2075			amt = 0;
2076	}
2077	return amt;
2078}
2079
2080/* Note:
2081 *  We use sk->sk_wq_raw, from contexts knowing this
2082 *  pointer is not NULL and cannot disappear/change.
2083 */
2084static inline void sk_set_bit(int nr, struct sock *sk)
2085{
2086	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2087	    !sock_flag(sk, SOCK_FASYNC))
2088		return;
2089
2090	set_bit(nr, &sk->sk_wq_raw->flags);
2091}
2092
2093static inline void sk_clear_bit(int nr, struct sock *sk)
2094{
2095	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2096	    !sock_flag(sk, SOCK_FASYNC))
2097		return;
2098
2099	clear_bit(nr, &sk->sk_wq_raw->flags);
2100}
2101
2102static inline void sk_wake_async(const struct sock *sk, int how, int band)
2103{
2104	if (sock_flag(sk, SOCK_FASYNC)) {
2105		rcu_read_lock();
2106		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2107		rcu_read_unlock();
2108	}
2109}
2110
2111/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2112 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2113 * Note: for send buffers, TCP works better if we can build two skbs at
2114 * minimum.
2115 */
2116#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2117
2118#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2119#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2120
2121static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2122{
2123	if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2124		sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2125		sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2126	}
2127}
2128
2129struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2130				    bool force_schedule);
 
 
 
2131
2132/**
2133 * sk_page_frag - return an appropriate page_frag
2134 * @sk: socket
2135 *
2136 * If socket allocation mode allows current thread to sleep, it means its
2137 * safe to use the per task page_frag instead of the per socket one.
 
 
 
 
 
 
 
 
 
2138 */
2139static inline struct page_frag *sk_page_frag(struct sock *sk)
2140{
2141	if (gfpflags_allow_blocking(sk->sk_allocation))
2142		return &current->task_frag;
2143
2144	return &sk->sk_frag;
2145}
2146
2147bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2148
2149int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2150		int sg_start, int *sg_curr, unsigned int *sg_size,
2151		int first_coalesce);
2152
2153/*
2154 *	Default write policy as shown to user space via poll/select/SIGIO
2155 */
2156static inline bool sock_writeable(const struct sock *sk)
2157{
2158	return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2159}
2160
2161static inline gfp_t gfp_any(void)
2162{
2163	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2164}
2165
 
 
 
 
 
2166static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2167{
2168	return noblock ? 0 : sk->sk_rcvtimeo;
2169}
2170
2171static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2172{
2173	return noblock ? 0 : sk->sk_sndtimeo;
2174}
2175
2176static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2177{
2178	return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
 
 
2179}
2180
2181/* Alas, with timeout socket operations are not restartable.
2182 * Compare this to poll().
2183 */
2184static inline int sock_intr_errno(long timeo)
2185{
2186	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2187}
2188
2189struct sock_skb_cb {
2190	u32 dropcount;
2191};
2192
2193/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2194 * using skb->cb[] would keep using it directly and utilize its
2195 * alignement guarantee.
2196 */
2197#define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
2198			    sizeof(struct sock_skb_cb)))
2199
2200#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2201			    SOCK_SKB_CB_OFFSET))
2202
2203#define sock_skb_cb_check_size(size) \
2204	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2205
2206static inline void
2207sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2208{
2209	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2210						atomic_read(&sk->sk_drops) : 0;
2211}
2212
2213static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2214{
2215	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2216
2217	atomic_add(segs, &sk->sk_drops);
2218}
2219
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2220void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2221			   struct sk_buff *skb);
2222void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2223			     struct sk_buff *skb);
2224
2225static inline void
2226sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2227{
2228	ktime_t kt = skb->tstamp;
2229	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2230
 
2231	/*
2232	 * generate control messages if
2233	 * - receive time stamping in software requested
2234	 * - software time stamp available and wanted
2235	 * - hardware time stamps available and wanted
2236	 */
2237	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2238	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2239	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2240	    (hwtstamps->hwtstamp &&
2241	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2242		__sock_recv_timestamp(msg, sk, skb);
2243	else
2244		sk->sk_stamp = kt;
2245
2246	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2247		__sock_recv_wifi_status(msg, sk, skb);
2248}
2249
2250void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2251			      struct sk_buff *skb);
2252
2253#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2254static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2255					  struct sk_buff *skb)
2256{
2257#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2258			   (1UL << SOCK_RCVTSTAMP))
 
2259#define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2260			   SOF_TIMESTAMPING_RAW_HARDWARE)
2261
2262	if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2263		__sock_recv_ts_and_drops(msg, sk, skb);
 
2264	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2265		sk->sk_stamp = skb->tstamp;
2266	else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2267		sk->sk_stamp = 0;
2268}
2269
2270void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2271
2272/**
2273 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2274 * @sk:		socket sending this packet
2275 * @tsflags:	timestamping flags to use
2276 * @tx_flags:	completed with instructions for time stamping
 
2277 *
2278 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2279 */
2280static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
2281				     __u8 *tx_flags)
2282{
2283	if (unlikely(tsflags))
2284		__sock_tx_timestamp(tsflags, tx_flags);
 
 
 
 
2285	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2286		*tx_flags |= SKBTX_WIFI_STATUS;
2287}
2288
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2289/**
2290 * sk_eat_skb - Release a skb if it is no longer needed
2291 * @sk: socket to eat this skb from
2292 * @skb: socket buffer to eat
2293 *
2294 * This routine must be called with interrupts disabled or with the socket
2295 * locked so that the sk_buff queue operation is ok.
2296*/
2297static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2298{
2299	__skb_unlink(skb, &sk->sk_receive_queue);
2300	__kfree_skb(skb);
2301}
2302
2303static inline
2304struct net *sock_net(const struct sock *sk)
2305{
2306	return read_pnet(&sk->sk_net);
 
 
 
 
2307}
2308
2309static inline
2310void sock_net_set(struct sock *sk, struct net *net)
 
 
2311{
2312	write_pnet(&sk->sk_net, net);
2313}
2314
2315static inline struct sock *skb_steal_sock(struct sk_buff *skb)
 
2316{
2317	if (skb->sk) {
2318		struct sock *sk = skb->sk;
2319
2320		skb->destructor = NULL;
2321		skb->sk = NULL;
2322		return sk;
2323	}
2324	return NULL;
2325}
2326
2327/* This helper checks if a socket is a full socket,
2328 * ie _not_ a timewait or request socket.
 
2329 */
2330static inline bool sk_fullsock(const struct sock *sk)
 
2331{
2332	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2333}
2334
2335/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2336 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2337 */
2338static inline bool sk_listener(const struct sock *sk)
2339{
2340	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2341}
2342
2343void sock_enable_timestamp(struct sock *sk, int flag);
2344int sock_get_timestamp(struct sock *, struct timeval __user *);
2345int sock_get_timestampns(struct sock *, struct timespec __user *);
2346int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2347		       int type);
2348
2349bool sk_ns_capable(const struct sock *sk,
2350		   struct user_namespace *user_ns, int cap);
2351bool sk_capable(const struct sock *sk, int cap);
2352bool sk_net_capable(const struct sock *sk, int cap);
2353
2354void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2355
2356/* Take into consideration the size of the struct sk_buff overhead in the
2357 * determination of these values, since that is non-constant across
2358 * platforms.  This makes socket queueing behavior and performance
2359 * not depend upon such differences.
2360 */
2361#define _SK_MEM_PACKETS		256
2362#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2363#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2364#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2365
2366extern __u32 sysctl_wmem_max;
2367extern __u32 sysctl_rmem_max;
2368
2369extern int sysctl_tstamp_allow_data;
2370extern int sysctl_optmem_max;
2371
2372extern __u32 sysctl_wmem_default;
2373extern __u32 sysctl_rmem_default;
2374
 
 
 
2375static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2376{
2377	/* Does this proto have per netns sysctl_wmem ? */
2378	if (proto->sysctl_wmem_offset)
2379		return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2380
2381	return *proto->sysctl_wmem;
2382}
2383
2384static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2385{
2386	/* Does this proto have per netns sysctl_rmem ? */
2387	if (proto->sysctl_rmem_offset)
2388		return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2389
2390	return *proto->sysctl_rmem;
2391}
2392
2393/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2394 * Some wifi drivers need to tweak it to get more chunks.
2395 * They can use this helper from their ndo_start_xmit()
2396 */
2397static inline void sk_pacing_shift_update(struct sock *sk, int val)
2398{
2399	if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val)
2400		return;
2401	sk->sk_pacing_shift = val;
2402}
2403
2404/* if a socket is bound to a device, check that the given device
2405 * index is either the same or that the socket is bound to an L3
2406 * master device and the given device index is also enslaved to
2407 * that L3 master
2408 */
2409static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2410{
 
2411	int mdif;
2412
2413	if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2414		return true;
2415
2416	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2417	if (mdif && mdif == sk->sk_bound_dev_if)
2418		return true;
2419
2420	return false;
2421}
2422
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2423#endif	/* _SOCK_H */
v6.9.4
   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 */
  83typedef 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
  98struct sock;
  99struct proto;
 100struct net;
 101
 102typedef __u32 __bitwise __portpair;
 103typedef __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 */
 150struct 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
 234struct bpf_local_storage;
 235struct sk_filter;
 236
 237/**
 238  *	struct sock - network layer representation of sockets
 239  *	@__sk_common: shared layout with inet_timewait_sock
 240  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
 241  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
 242  *	@sk_lock:	synchronizer
 243  *	@sk_kern_sock: True if sock is using kernel lock classes
 244  *	@sk_rcvbuf: size of receive buffer in bytes
 245  *	@sk_wq: sock wait queue and async head
 246  *	@sk_rx_dst: receive input route used by early demux
 247  *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
 248  *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
 249  *	@sk_dst_cache: destination cache
 250  *	@sk_dst_pending_confirm: need to confirm neighbour
 251  *	@sk_policy: flow policy
 252  *	@sk_receive_queue: incoming packets
 253  *	@sk_wmem_alloc: transmit queue bytes committed
 254  *	@sk_tsq_flags: TCP Small Queues flags
 255  *	@sk_write_queue: Packet sending queue
 256  *	@sk_omem_alloc: "o" is "option" or "other"
 257  *	@sk_wmem_queued: persistent queue size
 258  *	@sk_forward_alloc: space allocated forward
 259  *	@sk_reserved_mem: space reserved and non-reclaimable for the socket
 260  *	@sk_napi_id: id of the last napi context to receive data for sk
 261  *	@sk_ll_usec: usecs to busypoll when there is no data
 262  *	@sk_allocation: allocation mode
 263  *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
 264  *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
 265  *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
 266  *	@sk_sndbuf: size of send buffer in bytes
 
 
 267  *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
 268  *	@sk_no_check_rx: allow zero checksum in RX packets
 269  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
 270  *	@sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
 271  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
 272  *	@sk_gso_max_size: Maximum GSO segment size to build
 273  *	@sk_gso_max_segs: Maximum number of GSO segments
 274  *	@sk_pacing_shift: scaling factor for TCP Small Queues
 275  *	@sk_lingertime: %SO_LINGER l_linger setting
 276  *	@sk_backlog: always used with the per-socket spinlock held
 277  *	@sk_callback_lock: used with the callbacks in the end of this struct
 278  *	@sk_error_queue: rarely used
 279  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
 280  *			  IPV6_ADDRFORM for instance)
 281  *	@sk_err: last error
 282  *	@sk_err_soft: errors that don't cause failure but are the cause of a
 283  *		      persistent failure not just 'timed out'
 284  *	@sk_drops: raw/udp drops counter
 285  *	@sk_ack_backlog: current listen backlog
 286  *	@sk_max_ack_backlog: listen backlog set in listen()
 287  *	@sk_uid: user id of owner
 288  *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
 289  *	@sk_busy_poll_budget: napi processing budget when busypolling
 290  *	@sk_priority: %SO_PRIORITY setting
 291  *	@sk_type: socket type (%SOCK_STREAM, etc)
 292  *	@sk_protocol: which protocol this socket belongs in this network family
 293  *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
 294  *	@sk_peer_pid: &struct pid for this socket's peer
 295  *	@sk_peer_cred: %SO_PEERCRED setting
 296  *	@sk_rcvlowat: %SO_RCVLOWAT setting
 297  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
 298  *	@sk_sndtimeo: %SO_SNDTIMEO setting
 299  *	@sk_txhash: computed flow hash for use on transmit
 300  *	@sk_txrehash: enable TX hash rethink
 301  *	@sk_filter: socket filtering instructions
 302  *	@sk_timer: sock cleanup timer
 303  *	@sk_stamp: time stamp of last packet received
 304  *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
 305  *	@sk_tsflags: SO_TIMESTAMPING flags
 306  *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
 307  *			   Sockets that can be used under memory reclaim should
 308  *			   set this to false.
 309  *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
 310  *	              for timestamping
 311  *	@sk_tskey: counter to disambiguate concurrent tstamp requests
 312  *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
 313  *	@sk_socket: Identd and reporting IO signals
 314  *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
 315  *	@sk_frag: cached page frag
 316  *	@sk_peek_off: current peek_offset value
 317  *	@sk_send_head: front of stuff to transmit
 318  *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
 319  *	@sk_security: used by security modules
 320  *	@sk_mark: generic packet mark
 321  *	@sk_cgrp_data: cgroup data for this cgroup
 322  *	@sk_memcg: this socket's memory cgroup association
 323  *	@sk_write_pending: a write to stream socket waits to start
 324  *	@sk_disconnects: number of disconnect operations performed on this sock
 325  *	@sk_state_change: callback to indicate change in the state of the sock
 326  *	@sk_data_ready: callback to indicate there is data to be processed
 327  *	@sk_write_space: callback to indicate there is bf sending space available
 328  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
 329  *	@sk_backlog_rcv: callback to process the backlog
 330  *	@sk_validate_xmit_skb: ptr to an optional validate function
 331  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
 332  *	@sk_reuseport_cb: reuseport group container
 333  *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
 334  *	@sk_rcu: used during RCU grace period
 335  *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
 336  *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
 337  *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
 338  *	@sk_txtime_unused: unused txtime flags
 339  *	@ns_tracker: tracker for netns reference
 340  */
 341struct sock {
 342	/*
 343	 * Now struct inet_timewait_sock also uses sock_common, so please just
 344	 * don't add nothing before this first member (__sk_common) --acme
 345	 */
 346	struct sock_common	__sk_common;
 347#define sk_node			__sk_common.skc_node
 348#define sk_nulls_node		__sk_common.skc_nulls_node
 349#define sk_refcnt		__sk_common.skc_refcnt
 350#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
 351#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
 352#define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
 353#endif
 354
 355#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
 356#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
 357#define sk_hash			__sk_common.skc_hash
 358#define sk_portpair		__sk_common.skc_portpair
 359#define sk_num			__sk_common.skc_num
 360#define sk_dport		__sk_common.skc_dport
 361#define sk_addrpair		__sk_common.skc_addrpair
 362#define sk_daddr		__sk_common.skc_daddr
 363#define sk_rcv_saddr		__sk_common.skc_rcv_saddr
 364#define sk_family		__sk_common.skc_family
 365#define sk_state		__sk_common.skc_state
 366#define sk_reuse		__sk_common.skc_reuse
 367#define sk_reuseport		__sk_common.skc_reuseport
 368#define sk_ipv6only		__sk_common.skc_ipv6only
 369#define sk_net_refcnt		__sk_common.skc_net_refcnt
 370#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
 371#define sk_bind_node		__sk_common.skc_bind_node
 372#define sk_prot			__sk_common.skc_prot
 373#define sk_net			__sk_common.skc_net
 374#define sk_v6_daddr		__sk_common.skc_v6_daddr
 375#define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
 376#define sk_cookie		__sk_common.skc_cookie
 377#define sk_incoming_cpu		__sk_common.skc_incoming_cpu
 378#define sk_flags		__sk_common.skc_flags
 379#define sk_rxhash		__sk_common.skc_rxhash
 380
 381	__cacheline_group_begin(sock_write_rx);
 382
 383	atomic_t		sk_drops;
 384	__s32			sk_peek_off;
 385	struct sk_buff_head	sk_error_queue;
 386	struct sk_buff_head	sk_receive_queue;
 387	/*
 388	 * The backlog queue is special, it is always used with
 389	 * the per-socket spinlock held and requires low latency
 390	 * access. Therefore we special case it's implementation.
 391	 * Note : rmem_alloc is in this structure to fill a hole
 392	 * on 64bit arches, not because its logically part of
 393	 * backlog.
 394	 */
 395	struct {
 396		atomic_t	rmem_alloc;
 397		int		len;
 398		struct sk_buff	*head;
 399		struct sk_buff	*tail;
 400	} sk_backlog;
 401#define sk_rmem_alloc sk_backlog.rmem_alloc
 402
 403	__cacheline_group_end(sock_write_rx);
 404
 405	__cacheline_group_begin(sock_read_rx);
 406	/* early demux fields */
 407	struct dst_entry __rcu	*sk_rx_dst;
 408	int			sk_rx_dst_ifindex;
 409	u32			sk_rx_dst_cookie;
 410
 411#ifdef CONFIG_NET_RX_BUSY_POLL
 412	unsigned int		sk_ll_usec;
 
 413	unsigned int		sk_napi_id;
 414	u16			sk_busy_poll_budget;
 415	u8			sk_prefer_busy_poll;
 416#endif
 417	u8			sk_userlocks;
 418	int			sk_rcvbuf;
 419
 420	struct sk_filter __rcu	*sk_filter;
 421	union {
 422		struct socket_wq __rcu	*sk_wq;
 423		/* private: */
 424		struct socket_wq	*sk_wq_raw;
 425		/* public: */
 426	};
 427
 428	void			(*sk_data_ready)(struct sock *sk);
 429	long			sk_rcvtimeo;
 430	int			sk_rcvlowat;
 431	__cacheline_group_end(sock_read_rx);
 432
 433	__cacheline_group_begin(sock_read_rxtx);
 434	int			sk_err;
 435	struct socket		*sk_socket;
 436	struct mem_cgroup	*sk_memcg;
 437#ifdef CONFIG_XFRM
 438	struct xfrm_policy __rcu *sk_policy[2];
 439#endif
 440	__cacheline_group_end(sock_read_rxtx);
 441
 442	__cacheline_group_begin(sock_write_rxtx);
 443	socket_lock_t		sk_lock;
 444	u32			sk_reserved_mem;
 445	int			sk_forward_alloc;
 446	u32			sk_tsflags;
 447	__cacheline_group_end(sock_write_rxtx);
 448
 449	__cacheline_group_begin(sock_write_tx);
 450	int			sk_write_pending;
 451	atomic_t		sk_omem_alloc;
 452	int			sk_sndbuf;
 453
 
 454	int			sk_wmem_queued;
 455	refcount_t		sk_wmem_alloc;
 456	unsigned long		sk_tsq_flags;
 457	union {
 458		struct sk_buff	*sk_send_head;
 459		struct rb_root	tcp_rtx_queue;
 460	};
 461	struct sk_buff_head	sk_write_queue;
 462	u32			sk_dst_pending_confirm;
 
 
 463	u32			sk_pacing_status; /* see enum sk_pacing */
 
 
 
 
 
 
 464	struct page_frag	sk_frag;
 465	struct timer_list	sk_timer;
 466
 467	unsigned long		sk_pacing_rate; /* bytes per second */
 468	atomic_t		sk_zckey;
 469	atomic_t		sk_tskey;
 470	__cacheline_group_end(sock_write_tx);
 471
 472	__cacheline_group_begin(sock_read_tx);
 473	unsigned long		sk_max_pacing_rate;
 474	long			sk_sndtimeo;
 475	u32			sk_priority;
 476	u32			sk_mark;
 477	struct dst_entry __rcu	*sk_dst_cache;
 478	netdev_features_t	sk_route_caps;
 479#ifdef CONFIG_SOCK_VALIDATE_XMIT
 480	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
 481							struct net_device *dev,
 482							struct sk_buff *skb);
 483#endif
 484	u16			sk_gso_type;
 485	u16			sk_gso_max_segs;
 486	unsigned int		sk_gso_max_size;
 487	gfp_t			sk_allocation;
 488	u32			sk_txhash;
 489	u8			sk_pacing_shift;
 490	bool			sk_use_task_frag;
 491	__cacheline_group_end(sock_read_tx);
 492
 493	/*
 494	 * Because of non atomicity rules, all
 495	 * changes are protected by socket lock.
 496	 */
 497	u8			sk_gso_disabled : 1,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 498				sk_kern_sock : 1,
 499				sk_no_check_tx : 1,
 500				sk_no_check_rx : 1;
 501	u8			sk_shutdown;
 502	u16			sk_type;
 503	u16			sk_protocol;
 
 
 
 504	unsigned long	        sk_lingertime;
 505	struct proto		*sk_prot_creator;
 506	rwlock_t		sk_callback_lock;
 507	int			sk_err_soft;
 
 508	u32			sk_ack_backlog;
 509	u32			sk_max_ack_backlog;
 510	kuid_t			sk_uid;
 511	spinlock_t		sk_peer_lock;
 512	int			sk_bind_phc;
 513	struct pid		*sk_peer_pid;
 514	const struct cred	*sk_peer_cred;
 515
 516	ktime_t			sk_stamp;
 517#if BITS_PER_LONG==32
 518	seqlock_t		sk_stamp_seq;
 519#endif
 520	int			sk_disconnects;
 521
 522	u8			sk_txrehash;
 523	u8			sk_clockid;
 524	u8			sk_txtime_deadline_mode : 1,
 525				sk_txtime_report_errors : 1,
 526				sk_txtime_unused : 6;
 527
 528	void			*sk_user_data;
 529#ifdef CONFIG_SECURITY
 530	void			*sk_security;
 531#endif
 532	struct sock_cgroup_data	sk_cgrp_data;
 
 533	void			(*sk_state_change)(struct sock *sk);
 
 534	void			(*sk_write_space)(struct sock *sk);
 535	void			(*sk_error_report)(struct sock *sk);
 536	int			(*sk_backlog_rcv)(struct sock *sk,
 537						  struct sk_buff *skb);
 538	void                    (*sk_destruct)(struct sock *sk);
 539	struct sock_reuseport __rcu	*sk_reuseport_cb;
 540#ifdef CONFIG_BPF_SYSCALL
 541	struct bpf_local_storage __rcu	*sk_bpf_storage;
 542#endif
 543	struct rcu_head		sk_rcu;
 544	netns_tracker		ns_tracker;
 545};
 546
 547enum sk_pacing {
 548	SK_PACING_NONE		= 0,
 549	SK_PACING_NEEDED	= 1,
 550	SK_PACING_FQ		= 2,
 551};
 552
 553/* flag bits in sk_user_data
 554 *
 555 * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
 556 *   not be suitable for copying when cloning the socket. For instance,
 557 *   it can point to a reference counted object. sk_user_data bottom
 558 *   bit is set if pointer must not be copied.
 559 *
 560 * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
 561 *   managed/owned by a BPF reuseport array. This bit should be set
 562 *   when sk_user_data's sk is added to the bpf's reuseport_array.
 563 *
 564 * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
 565 *   sk_user_data points to psock type. This bit should be set
 566 *   when sk_user_data is assigned to a psock object.
 567 */
 568#define SK_USER_DATA_NOCOPY	1UL
 569#define SK_USER_DATA_BPF	2UL
 570#define SK_USER_DATA_PSOCK	4UL
 571#define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
 572				  SK_USER_DATA_PSOCK)
 573
 574/**
 575 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
 576 * @sk: socket
 577 */
 578static inline bool sk_user_data_is_nocopy(const struct sock *sk)
 579{
 580	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
 581}
 582
 583#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
 584
 585/**
 586 * __locked_read_sk_user_data_with_flags - return the pointer
 587 * only if argument flags all has been set in sk_user_data. Otherwise
 588 * return NULL
 589 *
 590 * @sk: socket
 591 * @flags: flag bits
 592 *
 593 * The caller must be holding sk->sk_callback_lock.
 594 */
 595static inline void *
 596__locked_read_sk_user_data_with_flags(const struct sock *sk,
 597				      uintptr_t flags)
 598{
 599	uintptr_t sk_user_data =
 600		(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
 601						 lockdep_is_held(&sk->sk_callback_lock));
 602
 603	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
 604
 605	if ((sk_user_data & flags) == flags)
 606		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
 607	return NULL;
 608}
 609
 610/**
 611 * __rcu_dereference_sk_user_data_with_flags - return the pointer
 612 * only if argument flags all has been set in sk_user_data. Otherwise
 613 * return NULL
 614 *
 615 * @sk: socket
 616 * @flags: flag bits
 617 */
 618static inline void *
 619__rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
 620					  uintptr_t flags)
 621{
 622	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
 623
 624	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
 625
 626	if ((sk_user_data & flags) == flags)
 627		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
 628	return NULL;
 629}
 630
 631#define rcu_dereference_sk_user_data(sk)				\
 632	__rcu_dereference_sk_user_data_with_flags(sk, 0)
 633#define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
 634({									\
 635	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
 636		  __tmp2 = (uintptr_t)(flags);				\
 637	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
 638	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
 639	rcu_assign_pointer(__sk_user_data((sk)),			\
 640			   __tmp1 | __tmp2);				\
 641})
 642#define rcu_assign_sk_user_data(sk, ptr)				\
 643	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
 644
 645static inline
 646struct net *sock_net(const struct sock *sk)
 647{
 648	return read_pnet(&sk->sk_net);
 649}
 650
 651static inline
 652void sock_net_set(struct sock *sk, struct net *net)
 653{
 654	write_pnet(&sk->sk_net, net);
 655}
 656
 657/*
 658 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 659 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 660 * on a socket means that the socket will reuse everybody else's port
 661 * without looking at the other's sk_reuse value.
 662 */
 663
 664#define SK_NO_REUSE	0
 665#define SK_CAN_REUSE	1
 666#define SK_FORCE_REUSE	2
 667
 668int sk_set_peek_off(struct sock *sk, int val);
 669
 670static inline int sk_peek_offset(const struct sock *sk, int flags)
 671{
 672	if (unlikely(flags & MSG_PEEK)) {
 673		return READ_ONCE(sk->sk_peek_off);
 674	}
 675
 676	return 0;
 677}
 678
 679static inline void sk_peek_offset_bwd(struct sock *sk, int val)
 680{
 681	s32 off = READ_ONCE(sk->sk_peek_off);
 682
 683	if (unlikely(off >= 0)) {
 684		off = max_t(s32, off - val, 0);
 685		WRITE_ONCE(sk->sk_peek_off, off);
 686	}
 687}
 688
 689static inline void sk_peek_offset_fwd(struct sock *sk, int val)
 690{
 691	sk_peek_offset_bwd(sk, -val);
 692}
 693
 694/*
 695 * Hashed lists helper routines
 696 */
 697static inline struct sock *sk_entry(const struct hlist_node *node)
 698{
 699	return hlist_entry(node, struct sock, sk_node);
 700}
 701
 702static inline struct sock *__sk_head(const struct hlist_head *head)
 703{
 704	return hlist_entry(head->first, struct sock, sk_node);
 705}
 706
 707static inline struct sock *sk_head(const struct hlist_head *head)
 708{
 709	return hlist_empty(head) ? NULL : __sk_head(head);
 710}
 711
 712static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
 713{
 714	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
 715}
 716
 717static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
 718{
 719	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
 720}
 721
 722static inline struct sock *sk_next(const struct sock *sk)
 723{
 724	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
 725}
 726
 727static inline struct sock *sk_nulls_next(const struct sock *sk)
 728{
 729	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
 730		hlist_nulls_entry(sk->sk_nulls_node.next,
 731				  struct sock, sk_nulls_node) :
 732		NULL;
 733}
 734
 735static inline bool sk_unhashed(const struct sock *sk)
 736{
 737	return hlist_unhashed(&sk->sk_node);
 738}
 739
 740static inline bool sk_hashed(const struct sock *sk)
 741{
 742	return !sk_unhashed(sk);
 743}
 744
 745static inline void sk_node_init(struct hlist_node *node)
 746{
 747	node->pprev = NULL;
 748}
 749
 
 
 
 
 
 750static inline void __sk_del_node(struct sock *sk)
 751{
 752	__hlist_del(&sk->sk_node);
 753}
 754
 755/* NB: equivalent to hlist_del_init_rcu */
 756static inline bool __sk_del_node_init(struct sock *sk)
 757{
 758	if (sk_hashed(sk)) {
 759		__sk_del_node(sk);
 760		sk_node_init(&sk->sk_node);
 761		return true;
 762	}
 763	return false;
 764}
 765
 766/* Grab socket reference count. This operation is valid only
 767   when sk is ALREADY grabbed f.e. it is found in hash table
 768   or a list and the lookup is made under lock preventing hash table
 769   modifications.
 770 */
 771
 772static __always_inline void sock_hold(struct sock *sk)
 773{
 774	refcount_inc(&sk->sk_refcnt);
 775}
 776
 777/* Ungrab socket in the context, which assumes that socket refcnt
 778   cannot hit zero, f.e. it is true in context of any socketcall.
 779 */
 780static __always_inline void __sock_put(struct sock *sk)
 781{
 782	refcount_dec(&sk->sk_refcnt);
 783}
 784
 785static inline bool sk_del_node_init(struct sock *sk)
 786{
 787	bool rc = __sk_del_node_init(sk);
 788
 789	if (rc) {
 790		/* paranoid for a while -acme */
 791		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 792		__sock_put(sk);
 793	}
 794	return rc;
 795}
 796#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
 797
 798static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
 799{
 800	if (sk_hashed(sk)) {
 801		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
 802		return true;
 803	}
 804	return false;
 805}
 806
 807static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
 808{
 809	bool rc = __sk_nulls_del_node_init_rcu(sk);
 810
 811	if (rc) {
 812		/* paranoid for a while -acme */
 813		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 814		__sock_put(sk);
 815	}
 816	return rc;
 817}
 818
 819static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
 820{
 821	hlist_add_head(&sk->sk_node, list);
 822}
 823
 824static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
 825{
 826	sock_hold(sk);
 827	__sk_add_node(sk, list);
 828}
 829
 830static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
 831{
 832	sock_hold(sk);
 833	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 834	    sk->sk_family == AF_INET6)
 835		hlist_add_tail_rcu(&sk->sk_node, list);
 836	else
 837		hlist_add_head_rcu(&sk->sk_node, list);
 838}
 839
 840static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
 841{
 842	sock_hold(sk);
 843	hlist_add_tail_rcu(&sk->sk_node, list);
 844}
 845
 846static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 847{
 848	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
 849}
 850
 851static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
 852{
 853	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
 854}
 855
 856static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 857{
 858	sock_hold(sk);
 859	__sk_nulls_add_node_rcu(sk, list);
 860}
 861
 862static inline void __sk_del_bind_node(struct sock *sk)
 863{
 864	__hlist_del(&sk->sk_bind_node);
 865}
 866
 867static inline void sk_add_bind_node(struct sock *sk,
 868					struct hlist_head *list)
 869{
 870	hlist_add_head(&sk->sk_bind_node, list);
 871}
 872
 873#define sk_for_each(__sk, list) \
 874	hlist_for_each_entry(__sk, list, sk_node)
 875#define sk_for_each_rcu(__sk, list) \
 876	hlist_for_each_entry_rcu(__sk, list, sk_node)
 877#define sk_nulls_for_each(__sk, node, list) \
 878	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
 879#define sk_nulls_for_each_rcu(__sk, node, list) \
 880	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
 881#define sk_for_each_from(__sk) \
 882	hlist_for_each_entry_from(__sk, sk_node)
 883#define sk_nulls_for_each_from(__sk, node) \
 884	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
 885		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
 886#define sk_for_each_safe(__sk, tmp, list) \
 887	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
 888#define sk_for_each_bound(__sk, list) \
 889	hlist_for_each_entry(__sk, list, sk_bind_node)
 890
 891/**
 892 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
 893 * @tpos:	the type * to use as a loop cursor.
 894 * @pos:	the &struct hlist_node to use as a loop cursor.
 895 * @head:	the head for your list.
 896 * @offset:	offset of hlist_node within the struct.
 897 *
 898 */
 899#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
 900	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
 901	     pos != NULL &&						       \
 902		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
 903	     pos = rcu_dereference(hlist_next_rcu(pos)))
 904
 905static inline struct user_namespace *sk_user_ns(const struct sock *sk)
 906{
 907	/* Careful only use this in a context where these parameters
 908	 * can not change and must all be valid, such as recvmsg from
 909	 * userspace.
 910	 */
 911	return sk->sk_socket->file->f_cred->user_ns;
 912}
 913
 914/* Sock flags */
 915enum sock_flags {
 916	SOCK_DEAD,
 917	SOCK_DONE,
 918	SOCK_URGINLINE,
 919	SOCK_KEEPOPEN,
 920	SOCK_LINGER,
 921	SOCK_DESTROY,
 922	SOCK_BROADCAST,
 923	SOCK_TIMESTAMP,
 924	SOCK_ZAPPED,
 925	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
 926	SOCK_DBG, /* %SO_DEBUG setting */
 927	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
 928	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
 929	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 
 930	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
 931	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
 932	SOCK_FASYNC, /* fasync() active */
 933	SOCK_RXQ_OVFL,
 934	SOCK_ZEROCOPY, /* buffers from userspace */
 935	SOCK_WIFI_STATUS, /* push wifi status to userspace */
 936	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
 937		     * Will use last 4 bytes of packet sent from
 938		     * user-space instead.
 939		     */
 940	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
 941	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
 942	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
 943	SOCK_TXTIME,
 944	SOCK_XDP, /* XDP is attached */
 945	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
 946	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
 947};
 948
 949#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
 950
 951static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
 952{
 953	nsk->sk_flags = osk->sk_flags;
 954}
 955
 956static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
 957{
 958	__set_bit(flag, &sk->sk_flags);
 959}
 960
 961static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
 962{
 963	__clear_bit(flag, &sk->sk_flags);
 964}
 965
 966static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
 967				     int valbool)
 968{
 969	if (valbool)
 970		sock_set_flag(sk, bit);
 971	else
 972		sock_reset_flag(sk, bit);
 973}
 974
 975static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
 976{
 977	return test_bit(flag, &sk->sk_flags);
 978}
 979
 980#ifdef CONFIG_NET
 981DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
 982static inline int sk_memalloc_socks(void)
 983{
 984	return static_branch_unlikely(&memalloc_socks_key);
 985}
 986
 987void __receive_sock(struct file *file);
 988#else
 989
 990static inline int sk_memalloc_socks(void)
 991{
 992	return 0;
 993}
 994
 995static inline void __receive_sock(struct file *file)
 996{ }
 997#endif
 998
 999static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1000{
1001	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1002}
1003
1004static inline void sk_acceptq_removed(struct sock *sk)
1005{
1006	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1007}
1008
1009static inline void sk_acceptq_added(struct sock *sk)
1010{
1011	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1012}
1013
1014/* Note: If you think the test should be:
1015 *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1016 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1017 */
1018static inline bool sk_acceptq_is_full(const struct sock *sk)
1019{
1020	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1021}
1022
1023/*
1024 * Compute minimal free write space needed to queue new packets.
1025 */
1026static inline int sk_stream_min_wspace(const struct sock *sk)
1027{
1028	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1029}
1030
1031static inline int sk_stream_wspace(const struct sock *sk)
1032{
1033	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1034}
1035
1036static inline void sk_wmem_queued_add(struct sock *sk, int val)
1037{
1038	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1039}
1040
1041static inline void sk_forward_alloc_add(struct sock *sk, int val)
1042{
1043	/* Paired with lockless reads of sk->sk_forward_alloc */
1044	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1045}
1046
1047void sk_stream_write_space(struct sock *sk);
1048
1049/* OOB backlog add */
1050static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1051{
1052	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1053	skb_dst_force(skb);
1054
1055	if (!sk->sk_backlog.tail)
1056		WRITE_ONCE(sk->sk_backlog.head, skb);
1057	else
1058		sk->sk_backlog.tail->next = skb;
1059
1060	WRITE_ONCE(sk->sk_backlog.tail, skb);
1061	skb->next = NULL;
1062}
1063
1064/*
1065 * Take into account size of receive queue and backlog queue
1066 * Do not take into account this skb truesize,
1067 * to allow even a single big packet to come.
1068 */
1069static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1070{
1071	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1072
1073	return qsize > limit;
1074}
1075
1076/* The per-socket spinlock must be held here. */
1077static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1078					      unsigned int limit)
1079{
1080	if (sk_rcvqueues_full(sk, limit))
1081		return -ENOBUFS;
1082
1083	/*
1084	 * If the skb was allocated from pfmemalloc reserves, only
1085	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1086	 * helping free memory
1087	 */
1088	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1089		return -ENOMEM;
1090
1091	__sk_add_backlog(sk, skb);
1092	sk->sk_backlog.len += skb->truesize;
1093	return 0;
1094}
1095
1096int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1097
1098INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1099INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1100
1101static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1102{
1103	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1104		return __sk_backlog_rcv(sk, skb);
1105
1106	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1107				  tcp_v6_do_rcv,
1108				  tcp_v4_do_rcv,
1109				  sk, skb);
1110}
1111
1112static inline void sk_incoming_cpu_update(struct sock *sk)
1113{
1114	int cpu = raw_smp_processor_id();
1115
1116	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1117		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
 
 
 
 
 
 
 
 
 
 
 
 
1118}
1119
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1120
1121static inline void sock_rps_save_rxhash(struct sock *sk,
1122					const struct sk_buff *skb)
1123{
1124#ifdef CONFIG_RPS
1125	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1126	 * here, and another one in sock_rps_record_flow().
1127	 */
1128	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1129		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1130#endif
1131}
1132
1133static inline void sock_rps_reset_rxhash(struct sock *sk)
1134{
1135#ifdef CONFIG_RPS
1136	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1137	WRITE_ONCE(sk->sk_rxhash, 0);
1138#endif
1139}
1140
1141#define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1142	({	int __rc, __dis = __sk->sk_disconnects;			\
1143		release_sock(__sk);					\
1144		__rc = __condition;					\
1145		if (!__rc) {						\
1146			*(__timeo) = wait_woken(__wait,			\
1147						TASK_INTERRUPTIBLE,	\
1148						*(__timeo));		\
1149		}							\
1150		sched_annotate_sleep();					\
1151		lock_sock(__sk);					\
1152		__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1153		__rc;							\
1154	})
1155
1156int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1157int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1158void sk_stream_wait_close(struct sock *sk, long timeo_p);
1159int sk_stream_error(struct sock *sk, int flags, int err);
1160void sk_stream_kill_queues(struct sock *sk);
1161void sk_set_memalloc(struct sock *sk);
1162void sk_clear_memalloc(struct sock *sk);
1163
1164void __sk_flush_backlog(struct sock *sk);
1165
1166static inline bool sk_flush_backlog(struct sock *sk)
1167{
1168	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1169		__sk_flush_backlog(sk);
1170		return true;
1171	}
1172	return false;
1173}
1174
1175int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1176
1177struct request_sock_ops;
1178struct timewait_sock_ops;
1179struct inet_hashinfo;
1180struct raw_hashinfo;
1181struct smc_hashinfo;
1182struct module;
1183struct sk_psock;
1184
1185/*
1186 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1187 * un-modified. Special care is taken when initializing object to zero.
1188 */
1189static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1190{
1191	if (offsetof(struct sock, sk_node.next) != 0)
1192		memset(sk, 0, offsetof(struct sock, sk_node.next));
1193	memset(&sk->sk_node.pprev, 0,
1194	       size - offsetof(struct sock, sk_node.pprev));
1195}
1196
1197/* Networking protocol blocks we attach to sockets.
1198 * socket layer -> transport layer interface
1199 */
1200struct proto {
1201	void			(*close)(struct sock *sk,
1202					long timeout);
1203	int			(*pre_connect)(struct sock *sk,
1204					struct sockaddr *uaddr,
1205					int addr_len);
1206	int			(*connect)(struct sock *sk,
1207					struct sockaddr *uaddr,
1208					int addr_len);
1209	int			(*disconnect)(struct sock *sk, int flags);
1210
1211	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1212					  bool kern);
1213
1214	int			(*ioctl)(struct sock *sk, int cmd,
1215					 int *karg);
1216	int			(*init)(struct sock *sk);
1217	void			(*destroy)(struct sock *sk);
1218	void			(*shutdown)(struct sock *sk, int how);
1219	int			(*setsockopt)(struct sock *sk, int level,
1220					int optname, sockptr_t optval,
1221					unsigned int optlen);
1222	int			(*getsockopt)(struct sock *sk, int level,
1223					int optname, char __user *optval,
1224					int __user *option);
1225	void			(*keepalive)(struct sock *sk, int valbool);
1226#ifdef CONFIG_COMPAT
 
 
 
 
 
 
 
 
1227	int			(*compat_ioctl)(struct sock *sk,
1228					unsigned int cmd, unsigned long arg);
1229#endif
1230	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1231					   size_t len);
1232	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1233					   size_t len, int flags, int *addr_len);
1234	void			(*splice_eof)(struct socket *sock);
 
 
1235	int			(*bind)(struct sock *sk,
1236					struct sockaddr *addr, int addr_len);
1237	int			(*bind_add)(struct sock *sk,
1238					struct sockaddr *addr, int addr_len);
1239
1240	int			(*backlog_rcv) (struct sock *sk,
1241						struct sk_buff *skb);
1242	bool			(*bpf_bypass_getsockopt)(int level,
1243							 int optname);
1244
1245	void		(*release_cb)(struct sock *sk);
1246
1247	/* Keeping track of sk's, looking them up, and port selection methods. */
1248	int			(*hash)(struct sock *sk);
1249	void			(*unhash)(struct sock *sk);
1250	void			(*rehash)(struct sock *sk);
1251	int			(*get_port)(struct sock *sk, unsigned short snum);
1252	void			(*put_port)(struct sock *sk);
1253#ifdef CONFIG_BPF_SYSCALL
1254	int			(*psock_update_sk_prot)(struct sock *sk,
1255							struct sk_psock *psock,
1256							bool restore);
1257#endif
1258
1259	/* Keeping track of sockets in use */
1260#ifdef CONFIG_PROC_FS
1261	unsigned int		inuse_idx;
1262#endif
1263
1264#if IS_ENABLED(CONFIG_MPTCP)
1265	int			(*forward_alloc_get)(const struct sock *sk);
1266#endif
1267
1268	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1269	bool			(*sock_is_readable)(struct sock *sk);
1270	/* Memory pressure */
1271	void			(*enter_memory_pressure)(struct sock *sk);
1272	void			(*leave_memory_pressure)(struct sock *sk);
1273	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1274	int  __percpu		*per_cpu_fw_alloc;
1275	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1276
1277	/*
1278	 * Pressure flag: try to collapse.
1279	 * Technical note: it is used by multiple contexts non atomically.
1280	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1281	 * All the __sk_mem_schedule() is of this nature: accounting
1282	 * is strict, actions are advisory and have some latency.
1283	 */
1284	unsigned long		*memory_pressure;
1285	long			*sysctl_mem;
1286
1287	int			*sysctl_wmem;
1288	int			*sysctl_rmem;
1289	u32			sysctl_wmem_offset;
1290	u32			sysctl_rmem_offset;
1291
1292	int			max_header;
1293	bool			no_autobind;
1294
1295	struct kmem_cache	*slab;
1296	unsigned int		obj_size;
1297	unsigned int		ipv6_pinfo_offset;
1298	slab_flags_t		slab_flags;
1299	unsigned int		useroffset;	/* Usercopy region offset */
1300	unsigned int		usersize;	/* Usercopy region size */
1301
1302	unsigned int __percpu	*orphan_count;
1303
1304	struct request_sock_ops	*rsk_prot;
1305	struct timewait_sock_ops *twsk_prot;
1306
1307	union {
1308		struct inet_hashinfo	*hashinfo;
1309		struct udp_table	*udp_table;
1310		struct raw_hashinfo	*raw_hash;
1311		struct smc_hashinfo	*smc_hash;
1312	} h;
1313
1314	struct module		*owner;
1315
1316	char			name[32];
1317
1318	struct list_head	node;
 
 
 
1319	int			(*diag_destroy)(struct sock *sk, int err);
1320} __randomize_layout;
1321
1322int proto_register(struct proto *prot, int alloc_slab);
1323void proto_unregister(struct proto *prot);
1324int sock_load_diag_module(int family, int protocol);
1325
1326INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
 
 
 
 
1327
1328static inline int sk_forward_alloc_get(const struct sock *sk)
1329{
1330#if IS_ENABLED(CONFIG_MPTCP)
1331	if (sk->sk_prot->forward_alloc_get)
1332		return sk->sk_prot->forward_alloc_get(sk);
1333#endif
1334	return READ_ONCE(sk->sk_forward_alloc);
1335}
1336
1337static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1338{
1339	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1340		return false;
1341
1342	return sk->sk_prot->stream_memory_free ?
1343		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1344				     tcp_stream_memory_free, sk, wake) : true;
1345}
 
 
 
 
 
1346
1347static inline bool sk_stream_memory_free(const struct sock *sk)
1348{
1349	return __sk_stream_memory_free(sk, 0);
1350}
1351
1352static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1353{
1354	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1355	       __sk_stream_memory_free(sk, wake);
1356}
1357
1358static inline bool sk_stream_is_writeable(const struct sock *sk)
1359{
1360	return __sk_stream_is_writeable(sk, 0);
 
1361}
1362
1363static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1364					    struct cgroup *ancestor)
1365{
1366#ifdef CONFIG_SOCK_CGROUP_DATA
1367	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1368				    ancestor);
1369#else
1370	return -ENOTSUPP;
1371#endif
1372}
1373
1374static inline bool sk_has_memory_pressure(const struct sock *sk)
1375{
1376	return sk->sk_prot->memory_pressure != NULL;
1377}
1378
1379static inline bool sk_under_global_memory_pressure(const struct sock *sk)
1380{
1381	return sk->sk_prot->memory_pressure &&
1382		!!READ_ONCE(*sk->sk_prot->memory_pressure);
1383}
1384
1385static inline bool sk_under_memory_pressure(const struct sock *sk)
1386{
1387	if (!sk->sk_prot->memory_pressure)
1388		return false;
1389
1390	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1391	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1392		return true;
1393
1394	return !!READ_ONCE(*sk->sk_prot->memory_pressure);
1395}
1396
1397static inline long
1398proto_memory_allocated(const struct proto *prot)
1399{
1400	return max(0L, atomic_long_read(prot->memory_allocated));
1401}
1402
1403static inline long
1404sk_memory_allocated(const struct sock *sk)
1405{
1406	return proto_memory_allocated(sk->sk_prot);
1407}
1408
1409/* 1 MB per cpu, in page units */
1410#define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT))
1411extern int sysctl_mem_pcpu_rsv;
1412
1413static inline void proto_memory_pcpu_drain(struct proto *proto)
1414{
1415	int val = this_cpu_xchg(*proto->per_cpu_fw_alloc, 0);
1416
1417	if (val)
1418		atomic_long_add(val, proto->memory_allocated);
1419}
1420
1421static inline void
1422sk_memory_allocated_add(const struct sock *sk, int val)
1423{
1424	struct proto *proto = sk->sk_prot;
1425
1426	val = this_cpu_add_return(*proto->per_cpu_fw_alloc, val);
1427
1428	if (unlikely(val >= READ_ONCE(sysctl_mem_pcpu_rsv)))
1429		proto_memory_pcpu_drain(proto);
1430}
1431
1432static inline void
1433sk_memory_allocated_sub(const struct sock *sk, int val)
1434{
1435	struct proto *proto = sk->sk_prot;
1436
1437	val = this_cpu_sub_return(*proto->per_cpu_fw_alloc, val);
1438
1439	if (unlikely(val <= -READ_ONCE(sysctl_mem_pcpu_rsv)))
1440		proto_memory_pcpu_drain(proto);
1441}
1442
1443#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1444
1445static inline void sk_sockets_allocated_dec(struct sock *sk)
1446{
1447	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1448				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1449}
1450
1451static inline void sk_sockets_allocated_inc(struct sock *sk)
1452{
1453	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1454				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1455}
1456
1457static inline u64
1458sk_sockets_allocated_read_positive(struct sock *sk)
1459{
1460	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1461}
1462
1463static inline int
1464proto_sockets_allocated_sum_positive(struct proto *prot)
1465{
1466	return percpu_counter_sum_positive(prot->sockets_allocated);
1467}
1468
 
 
 
 
 
 
1469static inline bool
1470proto_memory_pressure(struct proto *prot)
1471{
1472	if (!prot->memory_pressure)
1473		return false;
1474	return !!READ_ONCE(*prot->memory_pressure);
1475}
1476
1477
1478#ifdef CONFIG_PROC_FS
1479#define PROTO_INUSE_NR	64	/* should be enough for the first time */
1480struct prot_inuse {
1481	int all;
1482	int val[PROTO_INUSE_NR];
1483};
1484
1485static inline void sock_prot_inuse_add(const struct net *net,
1486				       const struct proto *prot, int val)
1487{
1488	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1489}
1490
1491static inline void sock_inuse_add(const struct net *net, int val)
1492{
1493	this_cpu_add(net->core.prot_inuse->all, val);
1494}
1495
1496int sock_prot_inuse_get(struct net *net, struct proto *proto);
1497int sock_inuse_get(struct net *net);
1498#else
1499static inline void sock_prot_inuse_add(const struct net *net,
1500				       const struct proto *prot, int val)
1501{
1502}
1503
1504static inline void sock_inuse_add(const struct net *net, int val)
1505{
1506}
1507#endif
1508
1509
1510/* With per-bucket locks this operation is not-atomic, so that
1511 * this version is not worse.
1512 */
1513static inline int __sk_prot_rehash(struct sock *sk)
1514{
1515	sk->sk_prot->unhash(sk);
1516	return sk->sk_prot->hash(sk);
1517}
1518
1519/* About 10 seconds */
1520#define SOCK_DESTROY_TIME (10*HZ)
1521
1522/* Sockets 0-1023 can't be bound to unless you are superuser */
1523#define PROT_SOCK	1024
1524
1525#define SHUTDOWN_MASK	3
1526#define RCV_SHUTDOWN	1
1527#define SEND_SHUTDOWN	2
1528
 
 
1529#define SOCK_BINDADDR_LOCK	4
1530#define SOCK_BINDPORT_LOCK	8
1531
1532struct socket_alloc {
1533	struct socket socket;
1534	struct inode vfs_inode;
1535};
1536
1537static inline struct socket *SOCKET_I(struct inode *inode)
1538{
1539	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1540}
1541
1542static inline struct inode *SOCK_INODE(struct socket *socket)
1543{
1544	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1545}
1546
1547/*
1548 * Functions for memory accounting
1549 */
1550int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1551int __sk_mem_schedule(struct sock *sk, int size, int kind);
1552void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1553void __sk_mem_reclaim(struct sock *sk, int amount);
1554
 
 
 
 
 
1555#define SK_MEM_SEND	0
1556#define SK_MEM_RECV	1
1557
1558/* sysctl_mem values are in pages */
1559static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1560{
1561	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
 
 
 
 
 
 
 
1562}
1563
1564static inline int sk_mem_pages(int amt)
1565{
1566	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1567}
1568
1569static inline bool sk_has_account(struct sock *sk)
1570{
1571	/* return true if protocol supports memory accounting */
1572	return !!sk->sk_prot->memory_allocated;
1573}
1574
1575static inline bool sk_wmem_schedule(struct sock *sk, int size)
1576{
1577	int delta;
1578
1579	if (!sk_has_account(sk))
1580		return true;
1581	delta = size - sk->sk_forward_alloc;
1582	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1583}
1584
1585static inline bool
1586sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1587{
1588	int delta;
1589
1590	if (!sk_has_account(sk))
1591		return true;
1592	delta = size - sk->sk_forward_alloc;
1593	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1594		skb_pfmemalloc(skb);
1595}
1596
1597static inline int sk_unused_reserved_mem(const struct sock *sk)
1598{
1599	int unused_mem;
1600
1601	if (likely(!sk->sk_reserved_mem))
1602		return 0;
1603
1604	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1605			atomic_read(&sk->sk_rmem_alloc);
1606
1607	return unused_mem > 0 ? unused_mem : 0;
1608}
1609
1610static inline void sk_mem_reclaim(struct sock *sk)
1611{
1612	int reclaimable;
1613
1614	if (!sk_has_account(sk))
1615		return;
1616
1617	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1618
1619	if (reclaimable >= (int)PAGE_SIZE)
1620		__sk_mem_reclaim(sk, reclaimable);
1621}
1622
1623static inline void sk_mem_reclaim_final(struct sock *sk)
1624{
1625	sk->sk_reserved_mem = 0;
1626	sk_mem_reclaim(sk);
 
 
1627}
1628
1629static inline void sk_mem_charge(struct sock *sk, int size)
1630{
1631	if (!sk_has_account(sk))
1632		return;
1633	sk_forward_alloc_add(sk, -size);
1634}
1635
1636static inline void sk_mem_uncharge(struct sock *sk, int size)
1637{
1638	if (!sk_has_account(sk))
1639		return;
1640	sk_forward_alloc_add(sk, size);
1641	sk_mem_reclaim(sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1642}
1643
1644/*
1645 * Macro so as to not evaluate some arguments when
1646 * lockdep is not enabled.
1647 *
1648 * Mark both the sk_lock and the sk_lock.slock as a
1649 * per-address-family lock class.
1650 */
1651#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1652do {									\
1653	sk->sk_lock.owned = 0;						\
1654	init_waitqueue_head(&sk->sk_lock.wq);				\
1655	spin_lock_init(&(sk)->sk_lock.slock);				\
1656	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1657			sizeof((sk)->sk_lock));				\
1658	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1659				(skey), (sname));				\
1660	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1661} while (0)
1662
 
1663static inline bool lockdep_sock_is_held(const struct sock *sk)
1664{
1665	return lockdep_is_held(&sk->sk_lock) ||
1666	       lockdep_is_held(&sk->sk_lock.slock);
1667}
 
1668
1669void lock_sock_nested(struct sock *sk, int subclass);
1670
1671static inline void lock_sock(struct sock *sk)
1672{
1673	lock_sock_nested(sk, 0);
1674}
1675
1676void __lock_sock(struct sock *sk);
1677void __release_sock(struct sock *sk);
1678void release_sock(struct sock *sk);
1679
1680/* BH context may only use the following locking interface. */
1681#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1682#define bh_lock_sock_nested(__sk) \
1683				spin_lock_nested(&((__sk)->sk_lock.slock), \
1684				SINGLE_DEPTH_NESTING)
1685#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1686
1687bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1688
1689/**
1690 * lock_sock_fast - fast version of lock_sock
1691 * @sk: socket
1692 *
1693 * This version should be used for very small section, where process wont block
1694 * return false if fast path is taken:
1695 *
1696 *   sk_lock.slock locked, owned = 0, BH disabled
1697 *
1698 * return true if slow path is taken:
1699 *
1700 *   sk_lock.slock unlocked, owned = 1, BH enabled
1701 */
1702static inline bool lock_sock_fast(struct sock *sk)
1703{
1704	/* The sk_lock has mutex_lock() semantics here. */
1705	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1706
1707	return __lock_sock_fast(sk);
1708}
1709
1710/* fast socket lock variant for caller already holding a [different] socket lock */
1711static inline bool lock_sock_fast_nested(struct sock *sk)
1712{
1713	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1714
1715	return __lock_sock_fast(sk);
1716}
1717
1718/**
1719 * unlock_sock_fast - complement of lock_sock_fast
1720 * @sk: socket
1721 * @slow: slow mode
1722 *
1723 * fast unlock socket for user context.
1724 * If slow mode is on, we call regular release_sock()
1725 */
1726static inline void unlock_sock_fast(struct sock *sk, bool slow)
1727	__releases(&sk->sk_lock.slock)
1728{
1729	if (slow) {
1730		release_sock(sk);
1731		__release(&sk->sk_lock.slock);
1732	} else {
1733		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1734		spin_unlock_bh(&sk->sk_lock.slock);
1735	}
1736}
1737
1738void sockopt_lock_sock(struct sock *sk);
1739void sockopt_release_sock(struct sock *sk);
1740bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1741bool sockopt_capable(int cap);
1742
1743/* Used by processes to "lock" a socket state, so that
1744 * interrupts and bottom half handlers won't change it
1745 * from under us. It essentially blocks any incoming
1746 * packets, so that we won't get any new data or any
1747 * packets that change the state of the socket.
1748 *
1749 * While locked, BH processing will add new packets to
1750 * the backlog queue.  This queue is processed by the
1751 * owner of the socket lock right before it is released.
1752 *
1753 * Since ~2.3.5 it is also exclusive sleep lock serializing
1754 * accesses from user process context.
1755 */
1756
1757static inline void sock_owned_by_me(const struct sock *sk)
1758{
1759#ifdef CONFIG_LOCKDEP
1760	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1761#endif
1762}
1763
1764static inline void sock_not_owned_by_me(const struct sock *sk)
1765{
1766#ifdef CONFIG_LOCKDEP
1767	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1768#endif
1769}
1770
1771static inline bool sock_owned_by_user(const struct sock *sk)
1772{
1773	sock_owned_by_me(sk);
1774	return sk->sk_lock.owned;
1775}
1776
1777static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1778{
1779	return sk->sk_lock.owned;
1780}
1781
1782static inline void sock_release_ownership(struct sock *sk)
1783{
1784	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1785	sk->sk_lock.owned = 0;
1786
1787	/* The sk_lock has mutex_unlock() semantics: */
1788	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1789}
1790
1791/* no reclassification while locks are held */
1792static inline bool sock_allow_reclassification(const struct sock *csk)
1793{
1794	struct sock *sk = (struct sock *)csk;
1795
1796	return !sock_owned_by_user_nocheck(sk) &&
1797		!spin_is_locked(&sk->sk_lock.slock);
1798}
1799
1800struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1801		      struct proto *prot, int kern);
1802void sk_free(struct sock *sk);
1803void sk_destruct(struct sock *sk);
1804struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1805void sk_free_unlock_clone(struct sock *sk);
1806
1807struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1808			     gfp_t priority);
1809void __sock_wfree(struct sk_buff *skb);
1810void sock_wfree(struct sk_buff *skb);
1811struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1812			     gfp_t priority);
1813void skb_orphan_partial(struct sk_buff *skb);
1814void sock_rfree(struct sk_buff *skb);
1815void sock_efree(struct sk_buff *skb);
1816#ifdef CONFIG_INET
1817void sock_edemux(struct sk_buff *skb);
1818void sock_pfree(struct sk_buff *skb);
1819#else
1820#define sock_edemux sock_efree
1821#endif
1822
1823int sk_setsockopt(struct sock *sk, int level, int optname,
1824		  sockptr_t optval, unsigned int optlen);
1825int sock_setsockopt(struct socket *sock, int level, int op,
1826		    sockptr_t optval, unsigned int optlen);
1827int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1828		       int optname, sockptr_t optval, int optlen);
1829int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1830		       int optname, sockptr_t optval, sockptr_t optlen);
1831
1832int sk_getsockopt(struct sock *sk, int level, int optname,
1833		  sockptr_t optval, sockptr_t optlen);
1834int sock_gettstamp(struct socket *sock, void __user *userstamp,
1835		   bool timeval, bool time32);
1836struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1837				     unsigned long data_len, int noblock,
1838				     int *errcode, int max_page_order);
1839
1840static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1841						  unsigned long size,
1842						  int noblock, int *errcode)
1843{
1844	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1845}
1846
1847void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1848void sock_kfree_s(struct sock *sk, void *mem, int size);
1849void sock_kzfree_s(struct sock *sk, void *mem, int size);
1850void sk_send_sigurg(struct sock *sk);
1851
1852static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1853{
1854	if (sk->sk_socket)
1855		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1856	WRITE_ONCE(sk->sk_prot, proto);
1857}
1858
1859struct sockcm_cookie {
1860	u64 transmit_time;
1861	u32 mark;
1862	u32 tsflags;
1863};
1864
1865static inline void sockcm_init(struct sockcm_cookie *sockc,
1866			       const struct sock *sk)
1867{
1868	*sockc = (struct sockcm_cookie) {
1869		.tsflags = READ_ONCE(sk->sk_tsflags)
1870	};
1871}
1872
1873int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1874		     struct sockcm_cookie *sockc);
1875int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1876		   struct sockcm_cookie *sockc);
1877
1878/*
1879 * Functions to fill in entries in struct proto_ops when a protocol
1880 * does not implement a particular function.
1881 */
1882int sock_no_bind(struct socket *, struct sockaddr *, int);
1883int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1884int sock_no_socketpair(struct socket *, struct socket *);
1885int sock_no_accept(struct socket *, struct socket *, int, bool);
1886int sock_no_getname(struct socket *, struct sockaddr *, int);
 
 
1887int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1888int sock_no_listen(struct socket *, int);
1889int sock_no_shutdown(struct socket *, int);
 
 
1890int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1891int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1892int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1893int sock_no_mmap(struct file *file, struct socket *sock,
1894		 struct vm_area_struct *vma);
 
 
 
 
1895
1896/*
1897 * Functions to fill in entries in struct proto_ops when a protocol
1898 * uses the inet style.
1899 */
1900int sock_common_getsockopt(struct socket *sock, int level, int optname,
1901				  char __user *optval, int __user *optlen);
1902int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1903			int flags);
1904int sock_common_setsockopt(struct socket *sock, int level, int optname,
1905			   sockptr_t optval, unsigned int optlen);
 
 
 
 
1906
1907void sk_common_release(struct sock *sk);
1908
1909/*
1910 *	Default socket callbacks and setup code
1911 */
1912
1913/* Initialise core socket variables using an explicit uid. */
1914void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1915
1916/* Initialise core socket variables.
1917 * Assumes struct socket *sock is embedded in a struct socket_alloc.
1918 */
1919void sock_init_data(struct socket *sock, struct sock *sk);
1920
1921/*
1922 * Socket reference counting postulates.
1923 *
1924 * * Each user of socket SHOULD hold a reference count.
1925 * * Each access point to socket (an hash table bucket, reference from a list,
1926 *   running timer, skb in flight MUST hold a reference count.
1927 * * When reference count hits 0, it means it will never increase back.
1928 * * When reference count hits 0, it means that no references from
1929 *   outside exist to this socket and current process on current CPU
1930 *   is last user and may/should destroy this socket.
1931 * * sk_free is called from any context: process, BH, IRQ. When
1932 *   it is called, socket has no references from outside -> sk_free
1933 *   may release descendant resources allocated by the socket, but
1934 *   to the time when it is called, socket is NOT referenced by any
1935 *   hash tables, lists etc.
1936 * * Packets, delivered from outside (from network or from another process)
1937 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1938 *   when they sit in queue. Otherwise, packets will leak to hole, when
1939 *   socket is looked up by one cpu and unhasing is made by another CPU.
1940 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1941 *   (leak to backlog). Packet socket does all the processing inside
1942 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1943 *   use separate SMP lock, so that they are prone too.
1944 */
1945
1946/* Ungrab socket and destroy it, if it was the last reference. */
1947static inline void sock_put(struct sock *sk)
1948{
1949	if (refcount_dec_and_test(&sk->sk_refcnt))
1950		sk_free(sk);
1951}
1952/* Generic version of sock_put(), dealing with all sockets
1953 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1954 */
1955void sock_gen_put(struct sock *sk);
1956
1957int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1958		     unsigned int trim_cap, bool refcounted);
1959static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1960				 const int nested)
1961{
1962	return __sk_receive_skb(sk, skb, nested, 1, true);
1963}
1964
1965static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1966{
1967	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1968	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1969		return;
1970	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1971	 * other WRITE_ONCE() because socket lock might be not held.
1972	 */
1973	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1974}
1975
1976#define NO_QUEUE_MAPPING	USHRT_MAX
1977
1978static inline void sk_tx_queue_clear(struct sock *sk)
1979{
1980	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1981	 * other WRITE_ONCE() because socket lock might be not held.
1982	 */
1983	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1984}
1985
1986static inline int sk_tx_queue_get(const struct sock *sk)
1987{
1988	if (sk) {
1989		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1990		 * and sk_tx_queue_set().
1991		 */
1992		int val = READ_ONCE(sk->sk_tx_queue_mapping);
1993
1994		if (val != NO_QUEUE_MAPPING)
1995			return val;
1996	}
1997	return -1;
1998}
1999
2000static inline void __sk_rx_queue_set(struct sock *sk,
2001				     const struct sk_buff *skb,
2002				     bool force_set)
2003{
2004#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2005	if (skb_rx_queue_recorded(skb)) {
2006		u16 rx_queue = skb_get_rx_queue(skb);
2007
2008		if (force_set ||
2009		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2010			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2011	}
2012#endif
2013}
2014
2015static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2016{
2017	__sk_rx_queue_set(sk, skb, true);
2018}
2019
2020static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2021{
2022	__sk_rx_queue_set(sk, skb, false);
2023}
2024
2025static inline void sk_rx_queue_clear(struct sock *sk)
2026{
2027#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2028	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2029#endif
2030}
2031
2032static inline int sk_rx_queue_get(const struct sock *sk)
2033{
2034#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2035	if (sk) {
2036		int res = READ_ONCE(sk->sk_rx_queue_mapping);
2037
2038		if (res != NO_QUEUE_MAPPING)
2039			return res;
2040	}
2041#endif
2042
2043	return -1;
2044}
2045
2046static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2047{
 
2048	sk->sk_socket = sock;
2049}
2050
2051static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2052{
2053	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2054	return &rcu_dereference_raw(sk->sk_wq)->wait;
2055}
2056/* Detach socket from process context.
2057 * Announce socket dead, detach it from wait queue and inode.
2058 * Note that parent inode held reference count on this struct sock,
2059 * we do not release it in this function, because protocol
2060 * probably wants some additional cleanups or even continuing
2061 * to work with this socket (TCP).
2062 */
2063static inline void sock_orphan(struct sock *sk)
2064{
2065	write_lock_bh(&sk->sk_callback_lock);
2066	sock_set_flag(sk, SOCK_DEAD);
2067	sk_set_socket(sk, NULL);
2068	sk->sk_wq  = NULL;
2069	write_unlock_bh(&sk->sk_callback_lock);
2070}
2071
2072static inline void sock_graft(struct sock *sk, struct socket *parent)
2073{
2074	WARN_ON(parent->sk);
2075	write_lock_bh(&sk->sk_callback_lock);
2076	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2077	parent->sk = sk;
2078	sk_set_socket(sk, parent);
2079	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2080	security_sock_graft(sk, parent);
2081	write_unlock_bh(&sk->sk_callback_lock);
2082}
2083
2084kuid_t sock_i_uid(struct sock *sk);
2085unsigned long __sock_i_ino(struct sock *sk);
2086unsigned long sock_i_ino(struct sock *sk);
2087
2088static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2089{
2090	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2091}
2092
2093static inline u32 net_tx_rndhash(void)
2094{
2095	u32 v = get_random_u32();
2096
2097	return v ?: 1;
2098}
2099
2100static inline void sk_set_txhash(struct sock *sk)
2101{
2102	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2103	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2104}
2105
2106static inline bool sk_rethink_txhash(struct sock *sk)
2107{
2108	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2109		sk_set_txhash(sk);
2110		return true;
2111	}
2112	return false;
2113}
2114
2115static inline struct dst_entry *
2116__sk_dst_get(const struct sock *sk)
2117{
2118	return rcu_dereference_check(sk->sk_dst_cache,
2119				     lockdep_sock_is_held(sk));
2120}
2121
2122static inline struct dst_entry *
2123sk_dst_get(const struct sock *sk)
2124{
2125	struct dst_entry *dst;
2126
2127	rcu_read_lock();
2128	dst = rcu_dereference(sk->sk_dst_cache);
2129	if (dst && !rcuref_get(&dst->__rcuref))
2130		dst = NULL;
2131	rcu_read_unlock();
2132	return dst;
2133}
2134
2135static inline void __dst_negative_advice(struct sock *sk)
2136{
2137	struct dst_entry *dst = __sk_dst_get(sk);
 
 
2138
2139	if (dst && dst->ops->negative_advice)
2140		dst->ops->negative_advice(sk, dst);
2141}
2142
2143static inline void dst_negative_advice(struct sock *sk)
2144{
2145	sk_rethink_txhash(sk);
2146	__dst_negative_advice(sk);
 
 
2147}
2148
2149static inline void
2150__sk_dst_set(struct sock *sk, struct dst_entry *dst)
2151{
2152	struct dst_entry *old_dst;
2153
2154	sk_tx_queue_clear(sk);
2155	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2156	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2157					    lockdep_sock_is_held(sk));
2158	rcu_assign_pointer(sk->sk_dst_cache, dst);
2159	dst_release(old_dst);
2160}
2161
2162static inline void
2163sk_dst_set(struct sock *sk, struct dst_entry *dst)
2164{
2165	struct dst_entry *old_dst;
2166
2167	sk_tx_queue_clear(sk);
2168	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2169	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2170	dst_release(old_dst);
2171}
2172
2173static inline void
2174__sk_dst_reset(struct sock *sk)
2175{
2176	__sk_dst_set(sk, NULL);
2177}
2178
2179static inline void
2180sk_dst_reset(struct sock *sk)
2181{
2182	sk_dst_set(sk, NULL);
2183}
2184
2185struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2186
2187struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2188
2189static inline void sk_dst_confirm(struct sock *sk)
2190{
2191	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2192		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2193}
2194
2195static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2196{
2197	if (skb_get_dst_pending_confirm(skb)) {
2198		struct sock *sk = skb->sk;
 
2199
2200		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2201			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2202		neigh_confirm(n);
 
 
2203	}
2204}
2205
2206bool sk_mc_loop(const struct sock *sk);
2207
2208static inline bool sk_can_gso(const struct sock *sk)
2209{
2210	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2211}
2212
2213void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2214
2215static inline void sk_gso_disable(struct sock *sk)
2216{
2217	sk->sk_gso_disabled = 1;
2218	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2219}
2220
2221static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2222					   struct iov_iter *from, char *to,
2223					   int copy, int offset)
2224{
2225	if (skb->ip_summed == CHECKSUM_NONE) {
2226		__wsum csum = 0;
2227		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2228			return -EFAULT;
2229		skb->csum = csum_block_add(skb->csum, csum, offset);
2230	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2231		if (!copy_from_iter_full_nocache(to, copy, from))
2232			return -EFAULT;
2233	} else if (!copy_from_iter_full(to, copy, from))
2234		return -EFAULT;
2235
2236	return 0;
2237}
2238
2239static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2240				       struct iov_iter *from, int copy)
2241{
2242	int err, offset = skb->len;
2243
2244	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2245				       copy, offset);
2246	if (err)
2247		__skb_trim(skb, offset);
2248
2249	return err;
2250}
2251
2252static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2253					   struct sk_buff *skb,
2254					   struct page *page,
2255					   int off, int copy)
2256{
2257	int err;
2258
2259	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2260				       copy, skb->len);
2261	if (err)
2262		return err;
2263
2264	skb_len_add(skb, copy);
2265	sk_wmem_queued_add(sk, copy);
 
 
2266	sk_mem_charge(sk, copy);
2267	return 0;
2268}
2269
2270/**
2271 * sk_wmem_alloc_get - returns write allocations
2272 * @sk: socket
2273 *
2274 * Return: sk_wmem_alloc minus initial offset of one
2275 */
2276static inline int sk_wmem_alloc_get(const struct sock *sk)
2277{
2278	return refcount_read(&sk->sk_wmem_alloc) - 1;
2279}
2280
2281/**
2282 * sk_rmem_alloc_get - returns read allocations
2283 * @sk: socket
2284 *
2285 * Return: sk_rmem_alloc
2286 */
2287static inline int sk_rmem_alloc_get(const struct sock *sk)
2288{
2289	return atomic_read(&sk->sk_rmem_alloc);
2290}
2291
2292/**
2293 * sk_has_allocations - check if allocations are outstanding
2294 * @sk: socket
2295 *
2296 * Return: true if socket has write or read allocations
2297 */
2298static inline bool sk_has_allocations(const struct sock *sk)
2299{
2300	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2301}
2302
2303/**
2304 * skwq_has_sleeper - check if there are any waiting processes
2305 * @wq: struct socket_wq
2306 *
2307 * Return: true if socket_wq has waiting processes
2308 *
2309 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2310 * barrier call. They were added due to the race found within the tcp code.
2311 *
2312 * Consider following tcp code paths::
2313 *
2314 *   CPU1                CPU2
2315 *   sys_select          receive packet
2316 *   ...                 ...
2317 *   __add_wait_queue    update tp->rcv_nxt
2318 *   ...                 ...
2319 *   tp->rcv_nxt check   sock_def_readable
2320 *   ...                 {
2321 *   schedule               rcu_read_lock();
2322 *                          wq = rcu_dereference(sk->sk_wq);
2323 *                          if (wq && waitqueue_active(&wq->wait))
2324 *                              wake_up_interruptible(&wq->wait)
2325 *                          ...
2326 *                       }
2327 *
2328 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2329 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2330 * could then endup calling schedule and sleep forever if there are no more
2331 * data on the socket.
2332 *
2333 */
2334static inline bool skwq_has_sleeper(struct socket_wq *wq)
2335{
2336	return wq && wq_has_sleeper(&wq->wait);
2337}
2338
2339/**
2340 * sock_poll_wait - place memory barrier behind the poll_wait call.
2341 * @filp:           file
2342 * @sock:           socket to wait on
2343 * @p:              poll_table
2344 *
2345 * See the comments in the wq_has_sleeper function.
2346 */
2347static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2348				  poll_table *p)
2349{
2350	if (!poll_does_not_wait(p)) {
2351		poll_wait(filp, &sock->wq.wait, p);
2352		/* We need to be sure we are in sync with the
2353		 * socket flags modification.
2354		 *
2355		 * This memory barrier is paired in the wq_has_sleeper.
2356		 */
2357		smp_mb();
2358	}
2359}
2360
2361static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2362{
2363	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2364	u32 txhash = READ_ONCE(sk->sk_txhash);
2365
2366	if (txhash) {
2367		skb->l4_hash = 1;
2368		skb->hash = txhash;
2369	}
2370}
2371
2372void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2373
2374/*
2375 *	Queue a received datagram if it will fit. Stream and sequenced
2376 *	protocols can't normally use this as they need to fit buffers in
2377 *	and play with them.
2378 *
2379 *	Inlined as it's very short and called for pretty much every
2380 *	packet ever received.
2381 */
2382static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2383{
2384	skb_orphan(skb);
2385	skb->sk = sk;
2386	skb->destructor = sock_rfree;
2387	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2388	sk_mem_charge(sk, skb->truesize);
2389}
2390
2391static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2392{
2393	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2394		skb_orphan(skb);
2395		skb->destructor = sock_efree;
2396		skb->sk = sk;
2397		return true;
2398	}
2399	return false;
2400}
2401
2402static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2403{
2404	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2405	if (skb) {
2406		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2407			skb_set_owner_r(skb, sk);
2408			return skb;
2409		}
2410		__kfree_skb(skb);
2411	}
2412	return NULL;
2413}
2414
2415static inline void skb_prepare_for_gro(struct sk_buff *skb)
2416{
2417	if (skb->destructor != sock_wfree) {
2418		skb_orphan(skb);
2419		return;
2420	}
2421	skb->slow_gro = 1;
2422}
2423
2424void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2425		    unsigned long expires);
2426
2427void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2428
2429void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2430
2431int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2432			struct sk_buff *skb, unsigned int flags,
2433			void (*destructor)(struct sock *sk,
2434					   struct sk_buff *skb));
2435int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2436
2437int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2438			      enum skb_drop_reason *reason);
2439
2440static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2441{
2442	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2443}
2444
2445int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2446struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2447
2448/*
2449 *	Recover an error report and clear atomically
2450 */
2451
2452static inline int sock_error(struct sock *sk)
2453{
2454	int err;
2455
2456	/* Avoid an atomic operation for the common case.
2457	 * This is racy since another cpu/thread can change sk_err under us.
2458	 */
2459	if (likely(data_race(!sk->sk_err)))
2460		return 0;
2461
2462	err = xchg(&sk->sk_err, 0);
2463	return -err;
2464}
2465
2466void sk_error_report(struct sock *sk);
2467
2468static inline unsigned long sock_wspace(struct sock *sk)
2469{
2470	int amt = 0;
2471
2472	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2473		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2474		if (amt < 0)
2475			amt = 0;
2476	}
2477	return amt;
2478}
2479
2480/* Note:
2481 *  We use sk->sk_wq_raw, from contexts knowing this
2482 *  pointer is not NULL and cannot disappear/change.
2483 */
2484static inline void sk_set_bit(int nr, struct sock *sk)
2485{
2486	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2487	    !sock_flag(sk, SOCK_FASYNC))
2488		return;
2489
2490	set_bit(nr, &sk->sk_wq_raw->flags);
2491}
2492
2493static inline void sk_clear_bit(int nr, struct sock *sk)
2494{
2495	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2496	    !sock_flag(sk, SOCK_FASYNC))
2497		return;
2498
2499	clear_bit(nr, &sk->sk_wq_raw->flags);
2500}
2501
2502static inline void sk_wake_async(const struct sock *sk, int how, int band)
2503{
2504	if (sock_flag(sk, SOCK_FASYNC)) {
2505		rcu_read_lock();
2506		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2507		rcu_read_unlock();
2508	}
2509}
2510
2511/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2512 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2513 * Note: for send buffers, TCP works better if we can build two skbs at
2514 * minimum.
2515 */
2516#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2517
2518#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2519#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2520
2521static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2522{
2523	u32 val;
2524
2525	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2526		return;
 
2527
2528	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2529	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2530
2531	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2532}
2533
2534/**
2535 * sk_page_frag - return an appropriate page_frag
2536 * @sk: socket
2537 *
2538 * Use the per task page_frag instead of the per socket one for
2539 * optimization when we know that we're in process context and own
2540 * everything that's associated with %current.
2541 *
2542 * Both direct reclaim and page faults can nest inside other
2543 * socket operations and end up recursing into sk_page_frag()
2544 * while it's already in use: explicitly avoid task page_frag
2545 * when users disable sk_use_task_frag.
2546 *
2547 * Return: a per task page_frag if context allows that,
2548 * otherwise a per socket one.
2549 */
2550static inline struct page_frag *sk_page_frag(struct sock *sk)
2551{
2552	if (sk->sk_use_task_frag)
2553		return &current->task_frag;
2554
2555	return &sk->sk_frag;
2556}
2557
2558bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2559
 
 
 
 
2560/*
2561 *	Default write policy as shown to user space via poll/select/SIGIO
2562 */
2563static inline bool sock_writeable(const struct sock *sk)
2564{
2565	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2566}
2567
2568static inline gfp_t gfp_any(void)
2569{
2570	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2571}
2572
2573static inline gfp_t gfp_memcg_charge(void)
2574{
2575	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2576}
2577
2578static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2579{
2580	return noblock ? 0 : sk->sk_rcvtimeo;
2581}
2582
2583static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2584{
2585	return noblock ? 0 : sk->sk_sndtimeo;
2586}
2587
2588static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2589{
2590	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2591
2592	return v ?: 1;
2593}
2594
2595/* Alas, with timeout socket operations are not restartable.
2596 * Compare this to poll().
2597 */
2598static inline int sock_intr_errno(long timeo)
2599{
2600	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2601}
2602
2603struct sock_skb_cb {
2604	u32 dropcount;
2605};
2606
2607/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2608 * using skb->cb[] would keep using it directly and utilize its
2609 * alignement guarantee.
2610 */
2611#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2612			    sizeof(struct sock_skb_cb)))
2613
2614#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2615			    SOCK_SKB_CB_OFFSET))
2616
2617#define sock_skb_cb_check_size(size) \
2618	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2619
2620static inline void
2621sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2622{
2623	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2624						atomic_read(&sk->sk_drops) : 0;
2625}
2626
2627static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2628{
2629	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2630
2631	atomic_add(segs, &sk->sk_drops);
2632}
2633
2634static inline ktime_t sock_read_timestamp(struct sock *sk)
2635{
2636#if BITS_PER_LONG==32
2637	unsigned int seq;
2638	ktime_t kt;
2639
2640	do {
2641		seq = read_seqbegin(&sk->sk_stamp_seq);
2642		kt = sk->sk_stamp;
2643	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2644
2645	return kt;
2646#else
2647	return READ_ONCE(sk->sk_stamp);
2648#endif
2649}
2650
2651static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2652{
2653#if BITS_PER_LONG==32
2654	write_seqlock(&sk->sk_stamp_seq);
2655	sk->sk_stamp = kt;
2656	write_sequnlock(&sk->sk_stamp_seq);
2657#else
2658	WRITE_ONCE(sk->sk_stamp, kt);
2659#endif
2660}
2661
2662void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2663			   struct sk_buff *skb);
2664void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2665			     struct sk_buff *skb);
2666
2667static inline void
2668sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2669{
 
2670	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2671	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2672	ktime_t kt = skb->tstamp;
2673	/*
2674	 * generate control messages if
2675	 * - receive time stamping in software requested
2676	 * - software time stamp available and wanted
2677	 * - hardware time stamps available and wanted
2678	 */
2679	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2680	    (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2681	    (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2682	    (hwtstamps->hwtstamp &&
2683	     (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2684		__sock_recv_timestamp(msg, sk, skb);
2685	else
2686		sock_write_timestamp(sk, kt);
2687
2688	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2689		__sock_recv_wifi_status(msg, sk, skb);
2690}
2691
2692void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2693		       struct sk_buff *skb);
2694
2695#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2696static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2697				   struct sk_buff *skb)
2698{
2699#define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2700			   (1UL << SOCK_RCVTSTAMP)			| \
2701			   (1UL << SOCK_RCVMARK))
2702#define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2703			   SOF_TIMESTAMPING_RAW_HARDWARE)
2704
2705	if (sk->sk_flags & FLAGS_RECV_CMSGS ||
2706	    READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY)
2707		__sock_recv_cmsgs(msg, sk, skb);
2708	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2709		sock_write_timestamp(sk, skb->tstamp);
2710	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2711		sock_write_timestamp(sk, 0);
2712}
2713
2714void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2715
2716/**
2717 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2718 * @sk:		socket sending this packet
2719 * @tsflags:	timestamping flags to use
2720 * @tx_flags:	completed with instructions for time stamping
2721 * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2722 *
2723 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2724 */
2725static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2726				      __u8 *tx_flags, __u32 *tskey)
2727{
2728	if (unlikely(tsflags)) {
2729		__sock_tx_timestamp(tsflags, tx_flags);
2730		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2731		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2732			*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2733	}
2734	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2735		*tx_flags |= SKBTX_WIFI_STATUS;
2736}
2737
2738static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2739				     __u8 *tx_flags)
2740{
2741	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2742}
2743
2744static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2745{
2746	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2747			   &skb_shinfo(skb)->tskey);
2748}
2749
2750static inline bool sk_is_inet(const struct sock *sk)
2751{
2752	int family = READ_ONCE(sk->sk_family);
2753
2754	return family == AF_INET || family == AF_INET6;
2755}
2756
2757static inline bool sk_is_tcp(const struct sock *sk)
2758{
2759	return sk_is_inet(sk) &&
2760	       sk->sk_type == SOCK_STREAM &&
2761	       sk->sk_protocol == IPPROTO_TCP;
2762}
2763
2764static inline bool sk_is_udp(const struct sock *sk)
2765{
2766	return sk_is_inet(sk) &&
2767	       sk->sk_type == SOCK_DGRAM &&
2768	       sk->sk_protocol == IPPROTO_UDP;
2769}
2770
2771static inline bool sk_is_stream_unix(const struct sock *sk)
2772{
2773	return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM;
2774}
2775
2776/**
2777 * sk_eat_skb - Release a skb if it is no longer needed
2778 * @sk: socket to eat this skb from
2779 * @skb: socket buffer to eat
2780 *
2781 * This routine must be called with interrupts disabled or with the socket
2782 * locked so that the sk_buff queue operation is ok.
2783*/
2784static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2785{
2786	__skb_unlink(skb, &sk->sk_receive_queue);
2787	__kfree_skb(skb);
2788}
2789
2790static inline bool
2791skb_sk_is_prefetched(struct sk_buff *skb)
2792{
2793#ifdef CONFIG_INET
2794	return skb->destructor == sock_pfree;
2795#else
2796	return false;
2797#endif /* CONFIG_INET */
2798}
2799
2800/* This helper checks if a socket is a full socket,
2801 * ie _not_ a timewait or request socket.
2802 */
2803static inline bool sk_fullsock(const struct sock *sk)
2804{
2805	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2806}
2807
2808static inline bool
2809sk_is_refcounted(struct sock *sk)
2810{
2811	/* Only full sockets have sk->sk_flags. */
2812	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
 
 
 
 
 
 
2813}
2814
2815/* Checks if this SKB belongs to an HW offloaded socket
2816 * and whether any SW fallbacks are required based on dev.
2817 * Check decrypted mark in case skb_orphan() cleared socket.
2818 */
2819static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2820						   struct net_device *dev)
2821{
2822#ifdef CONFIG_SOCK_VALIDATE_XMIT
2823	struct sock *sk = skb->sk;
2824
2825	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2826		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2827#ifdef CONFIG_TLS_DEVICE
2828	} else if (unlikely(skb->decrypted)) {
2829		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2830		kfree_skb(skb);
2831		skb = NULL;
2832#endif
2833	}
2834#endif
2835
2836	return skb;
2837}
2838
2839/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2840 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2841 */
2842static inline bool sk_listener(const struct sock *sk)
2843{
2844	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2845}
2846
2847void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
 
 
2848int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2849		       int type);
2850
2851bool sk_ns_capable(const struct sock *sk,
2852		   struct user_namespace *user_ns, int cap);
2853bool sk_capable(const struct sock *sk, int cap);
2854bool sk_net_capable(const struct sock *sk, int cap);
2855
2856void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2857
2858/* Take into consideration the size of the struct sk_buff overhead in the
2859 * determination of these values, since that is non-constant across
2860 * platforms.  This makes socket queueing behavior and performance
2861 * not depend upon such differences.
2862 */
2863#define _SK_MEM_PACKETS		256
2864#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2865#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2866#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2867
2868extern __u32 sysctl_wmem_max;
2869extern __u32 sysctl_rmem_max;
2870
2871extern int sysctl_tstamp_allow_data;
 
2872
2873extern __u32 sysctl_wmem_default;
2874extern __u32 sysctl_rmem_default;
2875
2876#define SKB_FRAG_PAGE_ORDER	get_order(32768)
2877DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2878
2879static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2880{
2881	/* Does this proto have per netns sysctl_wmem ? */
2882	if (proto->sysctl_wmem_offset)
2883		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2884
2885	return READ_ONCE(*proto->sysctl_wmem);
2886}
2887
2888static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2889{
2890	/* Does this proto have per netns sysctl_rmem ? */
2891	if (proto->sysctl_rmem_offset)
2892		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2893
2894	return READ_ONCE(*proto->sysctl_rmem);
2895}
2896
2897/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2898 * Some wifi drivers need to tweak it to get more chunks.
2899 * They can use this helper from their ndo_start_xmit()
2900 */
2901static inline void sk_pacing_shift_update(struct sock *sk, int val)
2902{
2903	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2904		return;
2905	WRITE_ONCE(sk->sk_pacing_shift, val);
2906}
2907
2908/* if a socket is bound to a device, check that the given device
2909 * index is either the same or that the socket is bound to an L3
2910 * master device and the given device index is also enslaved to
2911 * that L3 master
2912 */
2913static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2914{
2915	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2916	int mdif;
2917
2918	if (!bound_dev_if || bound_dev_if == dif)
2919		return true;
2920
2921	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2922	if (mdif && mdif == bound_dev_if)
2923		return true;
2924
2925	return false;
2926}
2927
2928void sock_def_readable(struct sock *sk);
2929
2930int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2931void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2932int sock_set_timestamping(struct sock *sk, int optname,
2933			  struct so_timestamping timestamping);
2934
2935void sock_enable_timestamps(struct sock *sk);
2936void sock_no_linger(struct sock *sk);
2937void sock_set_keepalive(struct sock *sk);
2938void sock_set_priority(struct sock *sk, u32 priority);
2939void sock_set_rcvbuf(struct sock *sk, int val);
2940void sock_set_mark(struct sock *sk, u32 val);
2941void sock_set_reuseaddr(struct sock *sk);
2942void sock_set_reuseport(struct sock *sk);
2943void sock_set_sndtimeo(struct sock *sk, s64 secs);
2944
2945int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2946
2947int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2948int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2949			   sockptr_t optval, int optlen, bool old_timeval);
2950
2951int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
2952		     void __user *arg, void *karg, size_t size);
2953int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
2954static inline bool sk_is_readable(struct sock *sk)
2955{
2956	if (sk->sk_prot->sock_is_readable)
2957		return sk->sk_prot->sock_is_readable(sk);
2958	return false;
2959}
2960#endif	/* _SOCK_H */