Linux Audio

Check our new training course

Loading...
v6.8
   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 *		Generic socket support routines. Memory allocators, socket lock/release
   8 *		handler for protocols to use and generic option handler.
   9 *
  10 * Authors:	Ross Biro
  11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *		Florian La Roche, <flla@stud.uni-sb.de>
  13 *		Alan Cox, <A.Cox@swansea.ac.uk>
  14 *
  15 * Fixes:
  16 *		Alan Cox	: 	Numerous verify_area() problems
  17 *		Alan Cox	:	Connecting on a connecting socket
  18 *					now returns an error for tcp.
  19 *		Alan Cox	:	sock->protocol is set correctly.
  20 *					and is not sometimes left as 0.
  21 *		Alan Cox	:	connect handles icmp errors on a
  22 *					connect properly. Unfortunately there
  23 *					is a restart syscall nasty there. I
  24 *					can't match BSD without hacking the C
  25 *					library. Ideas urgently sought!
  26 *		Alan Cox	:	Disallow bind() to addresses that are
  27 *					not ours - especially broadcast ones!!
  28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
  29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
  30 *					instead they leave that for the DESTROY timer.
  31 *		Alan Cox	:	Clean up error flag in accept
  32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
  33 *					was buggy. Put a remove_sock() in the handler
  34 *					for memory when we hit 0. Also altered the timer
  35 *					code. The ACK stuff can wait and needs major
  36 *					TCP layer surgery.
  37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
  38 *					and fixed timer/inet_bh race.
  39 *		Alan Cox	:	Added zapped flag for TCP
  40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
  41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
  42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
  43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
  44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
  45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
  46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
  47 *	Pauline Middelink	:	identd support
  48 *		Alan Cox	:	Fixed connect() taking signals I think.
  49 *		Alan Cox	:	SO_LINGER supported
  50 *		Alan Cox	:	Error reporting fixes
  51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
  52 *		Alan Cox	:	inet sockets don't set sk->type!
  53 *		Alan Cox	:	Split socket option code
  54 *		Alan Cox	:	Callbacks
  55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
  56 *		Alex		:	Removed restriction on inet fioctl
  57 *		Alan Cox	:	Splitting INET from NET core
  58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
  59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
  60 *		Alan Cox	:	Split IP from generic code
  61 *		Alan Cox	:	New kfree_skbmem()
  62 *		Alan Cox	:	Make SO_DEBUG superuser only.
  63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
  64 *					(compatibility fix)
  65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
  66 *		Alan Cox	:	Allocator for a socket is settable.
  67 *		Alan Cox	:	SO_ERROR includes soft errors.
  68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
  69 *		Alan Cox	: 	Generic socket allocation to make hooks
  70 *					easier (suggested by Craig Metz).
  71 *		Michael Pall	:	SO_ERROR returns positive errno again
  72 *              Steve Whitehouse:       Added default destructor to free
  73 *                                      protocol private data.
  74 *              Steve Whitehouse:       Added various other default routines
  75 *                                      common to several socket families.
  76 *              Chris Evans     :       Call suser() check last on F_SETOWN
  77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
  78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
  79 *		Andi Kleen	:	Fix write_space callback
  80 *		Chris Evans	:	Security fixes - signedness again
  81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
  82 *
  83 * To Fix:
  84 */
  85
  86#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  87
  88#include <asm/unaligned.h>
  89#include <linux/capability.h>
  90#include <linux/errno.h>
  91#include <linux/errqueue.h>
  92#include <linux/types.h>
  93#include <linux/socket.h>
  94#include <linux/in.h>
  95#include <linux/kernel.h>
  96#include <linux/module.h>
  97#include <linux/proc_fs.h>
  98#include <linux/seq_file.h>
  99#include <linux/sched.h>
 100#include <linux/sched/mm.h>
 101#include <linux/timer.h>
 102#include <linux/string.h>
 103#include <linux/sockios.h>
 104#include <linux/net.h>
 105#include <linux/mm.h>
 106#include <linux/slab.h>
 107#include <linux/interrupt.h>
 108#include <linux/poll.h>
 109#include <linux/tcp.h>
 110#include <linux/udp.h>
 111#include <linux/init.h>
 112#include <linux/highmem.h>
 113#include <linux/user_namespace.h>
 114#include <linux/static_key.h>
 115#include <linux/memcontrol.h>
 116#include <linux/prefetch.h>
 117#include <linux/compat.h>
 118#include <linux/mroute.h>
 119#include <linux/mroute6.h>
 120#include <linux/icmpv6.h>
 121
 122#include <linux/uaccess.h>
 123
 124#include <linux/netdevice.h>
 125#include <net/protocol.h>
 126#include <linux/skbuff.h>
 127#include <net/net_namespace.h>
 128#include <net/request_sock.h>
 129#include <net/sock.h>
 130#include <linux/net_tstamp.h>
 131#include <net/xfrm.h>
 132#include <linux/ipsec.h>
 133#include <net/cls_cgroup.h>
 134#include <net/netprio_cgroup.h>
 135#include <linux/sock_diag.h>
 136
 137#include <linux/filter.h>
 138#include <net/sock_reuseport.h>
 139#include <net/bpf_sk_storage.h>
 140
 141#include <trace/events/sock.h>
 142
 143#include <net/tcp.h>
 144#include <net/busy_poll.h>
 145#include <net/phonet/phonet.h>
 146
 147#include <linux/ethtool.h>
 148
 149#include "dev.h"
 150
 151static DEFINE_MUTEX(proto_list_mutex);
 152static LIST_HEAD(proto_list);
 153
 154static void sock_def_write_space_wfree(struct sock *sk);
 155static void sock_def_write_space(struct sock *sk);
 156
 157/**
 158 * sk_ns_capable - General socket capability test
 159 * @sk: Socket to use a capability on or through
 160 * @user_ns: The user namespace of the capability to use
 161 * @cap: The capability to use
 162 *
 163 * Test to see if the opener of the socket had when the socket was
 164 * created and the current process has the capability @cap in the user
 165 * namespace @user_ns.
 166 */
 167bool sk_ns_capable(const struct sock *sk,
 168		   struct user_namespace *user_ns, int cap)
 169{
 170	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
 171		ns_capable(user_ns, cap);
 172}
 173EXPORT_SYMBOL(sk_ns_capable);
 174
 175/**
 176 * sk_capable - Socket global capability test
 177 * @sk: Socket to use a capability on or through
 178 * @cap: The global capability to use
 179 *
 180 * Test to see if the opener of the socket had when the socket was
 181 * created and the current process has the capability @cap in all user
 182 * namespaces.
 183 */
 184bool sk_capable(const struct sock *sk, int cap)
 185{
 186	return sk_ns_capable(sk, &init_user_ns, cap);
 187}
 188EXPORT_SYMBOL(sk_capable);
 189
 190/**
 191 * sk_net_capable - Network namespace socket capability test
 192 * @sk: Socket to use a capability on or through
 193 * @cap: The capability to use
 194 *
 195 * Test to see if the opener of the socket had when the socket was created
 196 * and the current process has the capability @cap over the network namespace
 197 * the socket is a member of.
 198 */
 199bool sk_net_capable(const struct sock *sk, int cap)
 200{
 201	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
 202}
 203EXPORT_SYMBOL(sk_net_capable);
 204
 205/*
 206 * Each address family might have different locking rules, so we have
 207 * one slock key per address family and separate keys for internal and
 208 * userspace sockets.
 209 */
 210static struct lock_class_key af_family_keys[AF_MAX];
 211static struct lock_class_key af_family_kern_keys[AF_MAX];
 212static struct lock_class_key af_family_slock_keys[AF_MAX];
 213static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
 214
 215/*
 216 * Make lock validator output more readable. (we pre-construct these
 217 * strings build-time, so that runtime initialization of socket
 218 * locks is fast):
 219 */
 220
 221#define _sock_locks(x)						  \
 222  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
 223  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
 224  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
 225  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
 226  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
 227  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
 228  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
 229  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
 230  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
 231  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
 232  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
 233  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
 234  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
 235  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
 236  x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
 237  x "AF_MCTP"  , \
 238  x "AF_MAX"
 239
 240static const char *const af_family_key_strings[AF_MAX+1] = {
 241	_sock_locks("sk_lock-")
 242};
 243static const char *const af_family_slock_key_strings[AF_MAX+1] = {
 244	_sock_locks("slock-")
 245};
 246static const char *const af_family_clock_key_strings[AF_MAX+1] = {
 247	_sock_locks("clock-")
 248};
 249
 250static const char *const af_family_kern_key_strings[AF_MAX+1] = {
 251	_sock_locks("k-sk_lock-")
 252};
 253static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
 254	_sock_locks("k-slock-")
 255};
 256static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
 257	_sock_locks("k-clock-")
 258};
 259static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
 260	_sock_locks("rlock-")
 261};
 262static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
 263	_sock_locks("wlock-")
 264};
 265static const char *const af_family_elock_key_strings[AF_MAX+1] = {
 266	_sock_locks("elock-")
 267};
 268
 269/*
 270 * sk_callback_lock and sk queues locking rules are per-address-family,
 271 * so split the lock classes by using a per-AF key:
 272 */
 273static struct lock_class_key af_callback_keys[AF_MAX];
 274static struct lock_class_key af_rlock_keys[AF_MAX];
 275static struct lock_class_key af_wlock_keys[AF_MAX];
 276static struct lock_class_key af_elock_keys[AF_MAX];
 277static struct lock_class_key af_kern_callback_keys[AF_MAX];
 278
 279/* Run time adjustable parameters. */
 280__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 281EXPORT_SYMBOL(sysctl_wmem_max);
 282__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 283EXPORT_SYMBOL(sysctl_rmem_max);
 284__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 285__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 286
 
 
 
 
 287int sysctl_tstamp_allow_data __read_mostly = 1;
 288
 289DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
 290EXPORT_SYMBOL_GPL(memalloc_socks_key);
 291
 292/**
 293 * sk_set_memalloc - sets %SOCK_MEMALLOC
 294 * @sk: socket to set it on
 295 *
 296 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 297 * It's the responsibility of the admin to adjust min_free_kbytes
 298 * to meet the requirements
 299 */
 300void sk_set_memalloc(struct sock *sk)
 301{
 302	sock_set_flag(sk, SOCK_MEMALLOC);
 303	sk->sk_allocation |= __GFP_MEMALLOC;
 304	static_branch_inc(&memalloc_socks_key);
 305}
 306EXPORT_SYMBOL_GPL(sk_set_memalloc);
 307
 308void sk_clear_memalloc(struct sock *sk)
 309{
 310	sock_reset_flag(sk, SOCK_MEMALLOC);
 311	sk->sk_allocation &= ~__GFP_MEMALLOC;
 312	static_branch_dec(&memalloc_socks_key);
 313
 314	/*
 315	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 316	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 317	 * it has rmem allocations due to the last swapfile being deactivated
 318	 * but there is a risk that the socket is unusable due to exceeding
 319	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 320	 */
 321	sk_mem_reclaim(sk);
 322}
 323EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 324
 325int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 326{
 327	int ret;
 328	unsigned int noreclaim_flag;
 329
 330	/* these should have been dropped before queueing */
 331	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 332
 333	noreclaim_flag = memalloc_noreclaim_save();
 334	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
 335				 tcp_v6_do_rcv,
 336				 tcp_v4_do_rcv,
 337				 sk, skb);
 338	memalloc_noreclaim_restore(noreclaim_flag);
 339
 340	return ret;
 341}
 342EXPORT_SYMBOL(__sk_backlog_rcv);
 343
 344void sk_error_report(struct sock *sk)
 345{
 346	sk->sk_error_report(sk);
 347
 348	switch (sk->sk_family) {
 349	case AF_INET:
 350		fallthrough;
 351	case AF_INET6:
 352		trace_inet_sk_error_report(sk);
 353		break;
 354	default:
 355		break;
 356	}
 357}
 358EXPORT_SYMBOL(sk_error_report);
 359
 360int sock_get_timeout(long timeo, void *optval, bool old_timeval)
 361{
 362	struct __kernel_sock_timeval tv;
 363
 364	if (timeo == MAX_SCHEDULE_TIMEOUT) {
 365		tv.tv_sec = 0;
 366		tv.tv_usec = 0;
 367	} else {
 368		tv.tv_sec = timeo / HZ;
 369		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
 370	}
 371
 372	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 373		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
 374		*(struct old_timeval32 *)optval = tv32;
 375		return sizeof(tv32);
 376	}
 377
 378	if (old_timeval) {
 379		struct __kernel_old_timeval old_tv;
 380		old_tv.tv_sec = tv.tv_sec;
 381		old_tv.tv_usec = tv.tv_usec;
 382		*(struct __kernel_old_timeval *)optval = old_tv;
 383		return sizeof(old_tv);
 384	}
 385
 386	*(struct __kernel_sock_timeval *)optval = tv;
 387	return sizeof(tv);
 388}
 389EXPORT_SYMBOL(sock_get_timeout);
 390
 391int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
 392			   sockptr_t optval, int optlen, bool old_timeval)
 393{
 394	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 395		struct old_timeval32 tv32;
 396
 397		if (optlen < sizeof(tv32))
 398			return -EINVAL;
 399
 400		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
 401			return -EFAULT;
 402		tv->tv_sec = tv32.tv_sec;
 403		tv->tv_usec = tv32.tv_usec;
 404	} else if (old_timeval) {
 405		struct __kernel_old_timeval old_tv;
 406
 407		if (optlen < sizeof(old_tv))
 408			return -EINVAL;
 409		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
 410			return -EFAULT;
 411		tv->tv_sec = old_tv.tv_sec;
 412		tv->tv_usec = old_tv.tv_usec;
 413	} else {
 414		if (optlen < sizeof(*tv))
 415			return -EINVAL;
 416		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
 417			return -EFAULT;
 418	}
 419
 420	return 0;
 421}
 422EXPORT_SYMBOL(sock_copy_user_timeval);
 423
 424static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
 425			    bool old_timeval)
 426{
 427	struct __kernel_sock_timeval tv;
 428	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
 429	long val;
 430
 431	if (err)
 432		return err;
 433
 434	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 435		return -EDOM;
 436
 437	if (tv.tv_sec < 0) {
 438		static int warned __read_mostly;
 439
 440		WRITE_ONCE(*timeo_p, 0);
 441		if (warned < 10 && net_ratelimit()) {
 442			warned++;
 443			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 444				__func__, current->comm, task_pid_nr(current));
 445		}
 446		return 0;
 447	}
 448	val = MAX_SCHEDULE_TIMEOUT;
 449	if ((tv.tv_sec || tv.tv_usec) &&
 450	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
 451		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
 452						    USEC_PER_SEC / HZ);
 453	WRITE_ONCE(*timeo_p, val);
 454	return 0;
 455}
 456
 457static bool sock_needs_netstamp(const struct sock *sk)
 458{
 459	switch (sk->sk_family) {
 460	case AF_UNSPEC:
 461	case AF_UNIX:
 462		return false;
 463	default:
 464		return true;
 465	}
 466}
 467
 468static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 469{
 470	if (sk->sk_flags & flags) {
 471		sk->sk_flags &= ~flags;
 472		if (sock_needs_netstamp(sk) &&
 473		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 474			net_disable_timestamp();
 475	}
 476}
 477
 478
 479int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 480{
 481	unsigned long flags;
 482	struct sk_buff_head *list = &sk->sk_receive_queue;
 483
 484	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
 485		atomic_inc(&sk->sk_drops);
 486		trace_sock_rcvqueue_full(sk, skb);
 487		return -ENOMEM;
 488	}
 489
 490	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 491		atomic_inc(&sk->sk_drops);
 492		return -ENOBUFS;
 493	}
 494
 495	skb->dev = NULL;
 496	skb_set_owner_r(skb, sk);
 497
 498	/* we escape from rcu protected region, make sure we dont leak
 499	 * a norefcounted dst
 500	 */
 501	skb_dst_force(skb);
 502
 503	spin_lock_irqsave(&list->lock, flags);
 504	sock_skb_set_dropcount(sk, skb);
 505	__skb_queue_tail(list, skb);
 506	spin_unlock_irqrestore(&list->lock, flags);
 507
 508	if (!sock_flag(sk, SOCK_DEAD))
 509		sk->sk_data_ready(sk);
 510	return 0;
 511}
 512EXPORT_SYMBOL(__sock_queue_rcv_skb);
 513
 514int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
 515			      enum skb_drop_reason *reason)
 516{
 517	enum skb_drop_reason drop_reason;
 518	int err;
 519
 520	err = sk_filter(sk, skb);
 521	if (err) {
 522		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
 523		goto out;
 524	}
 525	err = __sock_queue_rcv_skb(sk, skb);
 526	switch (err) {
 527	case -ENOMEM:
 528		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
 529		break;
 530	case -ENOBUFS:
 531		drop_reason = SKB_DROP_REASON_PROTO_MEM;
 532		break;
 533	default:
 534		drop_reason = SKB_NOT_DROPPED_YET;
 535		break;
 536	}
 537out:
 538	if (reason)
 539		*reason = drop_reason;
 540	return err;
 541}
 542EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
 543
 544int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
 545		     const int nested, unsigned int trim_cap, bool refcounted)
 546{
 547	int rc = NET_RX_SUCCESS;
 548
 549	if (sk_filter_trim_cap(sk, skb, trim_cap))
 550		goto discard_and_relse;
 551
 552	skb->dev = NULL;
 553
 554	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 555		atomic_inc(&sk->sk_drops);
 556		goto discard_and_relse;
 557	}
 558	if (nested)
 559		bh_lock_sock_nested(sk);
 560	else
 561		bh_lock_sock(sk);
 562	if (!sock_owned_by_user(sk)) {
 563		/*
 564		 * trylock + unlock semantics:
 565		 */
 566		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 567
 568		rc = sk_backlog_rcv(sk, skb);
 569
 570		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
 571	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
 572		bh_unlock_sock(sk);
 573		atomic_inc(&sk->sk_drops);
 574		goto discard_and_relse;
 575	}
 576
 577	bh_unlock_sock(sk);
 578out:
 579	if (refcounted)
 580		sock_put(sk);
 581	return rc;
 582discard_and_relse:
 583	kfree_skb(skb);
 584	goto out;
 585}
 586EXPORT_SYMBOL(__sk_receive_skb);
 587
 588INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
 589							  u32));
 590INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
 591							   u32));
 592struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 593{
 594	struct dst_entry *dst = __sk_dst_get(sk);
 595
 596	if (dst && dst->obsolete &&
 597	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 598			       dst, cookie) == NULL) {
 599		sk_tx_queue_clear(sk);
 600		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
 601		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 602		dst_release(dst);
 603		return NULL;
 604	}
 605
 606	return dst;
 607}
 608EXPORT_SYMBOL(__sk_dst_check);
 609
 610struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 611{
 612	struct dst_entry *dst = sk_dst_get(sk);
 613
 614	if (dst && dst->obsolete &&
 615	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 616			       dst, cookie) == NULL) {
 617		sk_dst_reset(sk);
 618		dst_release(dst);
 619		return NULL;
 620	}
 621
 622	return dst;
 623}
 624EXPORT_SYMBOL(sk_dst_check);
 625
 626static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
 627{
 628	int ret = -ENOPROTOOPT;
 629#ifdef CONFIG_NETDEVICES
 630	struct net *net = sock_net(sk);
 631
 632	/* Sorry... */
 633	ret = -EPERM;
 634	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
 635		goto out;
 636
 637	ret = -EINVAL;
 638	if (ifindex < 0)
 639		goto out;
 640
 641	/* Paired with all READ_ONCE() done locklessly. */
 642	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
 643
 644	if (sk->sk_prot->rehash)
 645		sk->sk_prot->rehash(sk);
 646	sk_dst_reset(sk);
 647
 648	ret = 0;
 649
 650out:
 651#endif
 652
 653	return ret;
 654}
 655
 656int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
 657{
 658	int ret;
 659
 660	if (lock_sk)
 661		lock_sock(sk);
 662	ret = sock_bindtoindex_locked(sk, ifindex);
 663	if (lock_sk)
 664		release_sock(sk);
 665
 666	return ret;
 667}
 668EXPORT_SYMBOL(sock_bindtoindex);
 669
 670static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
 671{
 672	int ret = -ENOPROTOOPT;
 673#ifdef CONFIG_NETDEVICES
 674	struct net *net = sock_net(sk);
 675	char devname[IFNAMSIZ];
 676	int index;
 677
 678	ret = -EINVAL;
 679	if (optlen < 0)
 680		goto out;
 681
 682	/* Bind this socket to a particular device like "eth0",
 683	 * as specified in the passed interface name. If the
 684	 * name is "" or the option length is zero the socket
 685	 * is not bound.
 686	 */
 687	if (optlen > IFNAMSIZ - 1)
 688		optlen = IFNAMSIZ - 1;
 689	memset(devname, 0, sizeof(devname));
 690
 691	ret = -EFAULT;
 692	if (copy_from_sockptr(devname, optval, optlen))
 693		goto out;
 694
 695	index = 0;
 696	if (devname[0] != '\0') {
 697		struct net_device *dev;
 698
 699		rcu_read_lock();
 700		dev = dev_get_by_name_rcu(net, devname);
 701		if (dev)
 702			index = dev->ifindex;
 703		rcu_read_unlock();
 704		ret = -ENODEV;
 705		if (!dev)
 706			goto out;
 707	}
 708
 709	sockopt_lock_sock(sk);
 710	ret = sock_bindtoindex_locked(sk, index);
 711	sockopt_release_sock(sk);
 712out:
 713#endif
 714
 715	return ret;
 716}
 717
 718static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
 719				sockptr_t optlen, int len)
 720{
 721	int ret = -ENOPROTOOPT;
 722#ifdef CONFIG_NETDEVICES
 723	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 724	struct net *net = sock_net(sk);
 725	char devname[IFNAMSIZ];
 726
 727	if (bound_dev_if == 0) {
 728		len = 0;
 729		goto zero;
 730	}
 731
 732	ret = -EINVAL;
 733	if (len < IFNAMSIZ)
 734		goto out;
 735
 736	ret = netdev_get_name(net, devname, bound_dev_if);
 737	if (ret)
 738		goto out;
 739
 740	len = strlen(devname) + 1;
 741
 742	ret = -EFAULT;
 743	if (copy_to_sockptr(optval, devname, len))
 744		goto out;
 745
 746zero:
 747	ret = -EFAULT;
 748	if (copy_to_sockptr(optlen, &len, sizeof(int)))
 749		goto out;
 750
 751	ret = 0;
 752
 753out:
 754#endif
 755
 756	return ret;
 757}
 758
 759bool sk_mc_loop(const struct sock *sk)
 760{
 761	if (dev_recursion_level())
 762		return false;
 763	if (!sk)
 764		return true;
 765	/* IPV6_ADDRFORM can change sk->sk_family under us. */
 766	switch (READ_ONCE(sk->sk_family)) {
 767	case AF_INET:
 768		return inet_test_bit(MC_LOOP, sk);
 769#if IS_ENABLED(CONFIG_IPV6)
 770	case AF_INET6:
 771		return inet6_test_bit(MC6_LOOP, sk);
 772#endif
 773	}
 774	WARN_ON_ONCE(1);
 775	return true;
 776}
 777EXPORT_SYMBOL(sk_mc_loop);
 778
 779void sock_set_reuseaddr(struct sock *sk)
 780{
 781	lock_sock(sk);
 782	sk->sk_reuse = SK_CAN_REUSE;
 783	release_sock(sk);
 784}
 785EXPORT_SYMBOL(sock_set_reuseaddr);
 786
 787void sock_set_reuseport(struct sock *sk)
 788{
 789	lock_sock(sk);
 790	sk->sk_reuseport = true;
 791	release_sock(sk);
 792}
 793EXPORT_SYMBOL(sock_set_reuseport);
 794
 795void sock_no_linger(struct sock *sk)
 796{
 797	lock_sock(sk);
 798	WRITE_ONCE(sk->sk_lingertime, 0);
 799	sock_set_flag(sk, SOCK_LINGER);
 800	release_sock(sk);
 801}
 802EXPORT_SYMBOL(sock_no_linger);
 803
 804void sock_set_priority(struct sock *sk, u32 priority)
 805{
 806	WRITE_ONCE(sk->sk_priority, priority);
 
 
 807}
 808EXPORT_SYMBOL(sock_set_priority);
 809
 810void sock_set_sndtimeo(struct sock *sk, s64 secs)
 811{
 812	lock_sock(sk);
 813	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
 814		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
 815	else
 816		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
 817	release_sock(sk);
 818}
 819EXPORT_SYMBOL(sock_set_sndtimeo);
 820
 821static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
 822{
 823	if (val)  {
 824		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
 825		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
 826		sock_set_flag(sk, SOCK_RCVTSTAMP);
 827		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 828	} else {
 829		sock_reset_flag(sk, SOCK_RCVTSTAMP);
 830		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 831	}
 832}
 833
 834void sock_enable_timestamps(struct sock *sk)
 835{
 836	lock_sock(sk);
 837	__sock_set_timestamps(sk, true, false, true);
 838	release_sock(sk);
 839}
 840EXPORT_SYMBOL(sock_enable_timestamps);
 841
 842void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
 843{
 844	switch (optname) {
 845	case SO_TIMESTAMP_OLD:
 846		__sock_set_timestamps(sk, valbool, false, false);
 847		break;
 848	case SO_TIMESTAMP_NEW:
 849		__sock_set_timestamps(sk, valbool, true, false);
 850		break;
 851	case SO_TIMESTAMPNS_OLD:
 852		__sock_set_timestamps(sk, valbool, false, true);
 853		break;
 854	case SO_TIMESTAMPNS_NEW:
 855		__sock_set_timestamps(sk, valbool, true, true);
 856		break;
 857	}
 858}
 859
 860static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
 861{
 862	struct net *net = sock_net(sk);
 863	struct net_device *dev = NULL;
 864	bool match = false;
 865	int *vclock_index;
 866	int i, num;
 867
 868	if (sk->sk_bound_dev_if)
 869		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
 870
 871	if (!dev) {
 872		pr_err("%s: sock not bind to device\n", __func__);
 873		return -EOPNOTSUPP;
 874	}
 875
 876	num = ethtool_get_phc_vclocks(dev, &vclock_index);
 877	dev_put(dev);
 878
 879	for (i = 0; i < num; i++) {
 880		if (*(vclock_index + i) == phc_index) {
 881			match = true;
 882			break;
 883		}
 884	}
 885
 886	if (num > 0)
 887		kfree(vclock_index);
 888
 889	if (!match)
 890		return -EINVAL;
 891
 892	WRITE_ONCE(sk->sk_bind_phc, phc_index);
 893
 894	return 0;
 895}
 896
 897int sock_set_timestamping(struct sock *sk, int optname,
 898			  struct so_timestamping timestamping)
 899{
 900	int val = timestamping.flags;
 901	int ret;
 902
 903	if (val & ~SOF_TIMESTAMPING_MASK)
 904		return -EINVAL;
 905
 906	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
 907	    !(val & SOF_TIMESTAMPING_OPT_ID))
 908		return -EINVAL;
 909
 910	if (val & SOF_TIMESTAMPING_OPT_ID &&
 911	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
 912		if (sk_is_tcp(sk)) {
 913			if ((1 << sk->sk_state) &
 914			    (TCPF_CLOSE | TCPF_LISTEN))
 915				return -EINVAL;
 916			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
 917				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
 918			else
 919				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
 920		} else {
 921			atomic_set(&sk->sk_tskey, 0);
 922		}
 923	}
 924
 925	if (val & SOF_TIMESTAMPING_OPT_STATS &&
 926	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
 927		return -EINVAL;
 928
 929	if (val & SOF_TIMESTAMPING_BIND_PHC) {
 930		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
 931		if (ret)
 932			return ret;
 933	}
 934
 935	WRITE_ONCE(sk->sk_tsflags, val);
 936	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
 937
 938	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
 939		sock_enable_timestamp(sk,
 940				      SOCK_TIMESTAMPING_RX_SOFTWARE);
 941	else
 942		sock_disable_timestamp(sk,
 943				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
 944	return 0;
 945}
 946
 947void sock_set_keepalive(struct sock *sk)
 948{
 949	lock_sock(sk);
 950	if (sk->sk_prot->keepalive)
 951		sk->sk_prot->keepalive(sk, true);
 952	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
 953	release_sock(sk);
 954}
 955EXPORT_SYMBOL(sock_set_keepalive);
 956
 957static void __sock_set_rcvbuf(struct sock *sk, int val)
 958{
 959	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
 960	 * as a negative value.
 961	 */
 962	val = min_t(int, val, INT_MAX / 2);
 963	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 964
 965	/* We double it on the way in to account for "struct sk_buff" etc.
 966	 * overhead.   Applications assume that the SO_RCVBUF setting they make
 967	 * will allow that much actual data to be received on that socket.
 968	 *
 969	 * Applications are unaware that "struct sk_buff" and other overheads
 970	 * allocate from the receive buffer during socket buffer allocation.
 971	 *
 972	 * And after considering the possible alternatives, returning the value
 973	 * we actually used in getsockopt is the most desirable behavior.
 974	 */
 975	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
 976}
 977
 978void sock_set_rcvbuf(struct sock *sk, int val)
 979{
 980	lock_sock(sk);
 981	__sock_set_rcvbuf(sk, val);
 982	release_sock(sk);
 983}
 984EXPORT_SYMBOL(sock_set_rcvbuf);
 985
 986static void __sock_set_mark(struct sock *sk, u32 val)
 987{
 988	if (val != sk->sk_mark) {
 989		WRITE_ONCE(sk->sk_mark, val);
 990		sk_dst_reset(sk);
 991	}
 992}
 993
 994void sock_set_mark(struct sock *sk, u32 val)
 995{
 996	lock_sock(sk);
 997	__sock_set_mark(sk, val);
 998	release_sock(sk);
 999}
1000EXPORT_SYMBOL(sock_set_mark);
1001
1002static void sock_release_reserved_memory(struct sock *sk, int bytes)
1003{
1004	/* Round down bytes to multiple of pages */
1005	bytes = round_down(bytes, PAGE_SIZE);
1006
1007	WARN_ON(bytes > sk->sk_reserved_mem);
1008	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1009	sk_mem_reclaim(sk);
1010}
1011
1012static int sock_reserve_memory(struct sock *sk, int bytes)
1013{
1014	long allocated;
1015	bool charged;
1016	int pages;
1017
1018	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1019		return -EOPNOTSUPP;
1020
1021	if (!bytes)
1022		return 0;
1023
1024	pages = sk_mem_pages(bytes);
1025
1026	/* pre-charge to memcg */
1027	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1028					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1029	if (!charged)
1030		return -ENOMEM;
1031
1032	/* pre-charge to forward_alloc */
1033	sk_memory_allocated_add(sk, pages);
1034	allocated = sk_memory_allocated(sk);
1035	/* If the system goes into memory pressure with this
1036	 * precharge, give up and return error.
1037	 */
1038	if (allocated > sk_prot_mem_limits(sk, 1)) {
1039		sk_memory_allocated_sub(sk, pages);
1040		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1041		return -ENOMEM;
1042	}
1043	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1044
1045	WRITE_ONCE(sk->sk_reserved_mem,
1046		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1047
1048	return 0;
1049}
1050
1051void sockopt_lock_sock(struct sock *sk)
1052{
1053	/* When current->bpf_ctx is set, the setsockopt is called from
1054	 * a bpf prog.  bpf has ensured the sk lock has been
1055	 * acquired before calling setsockopt().
1056	 */
1057	if (has_current_bpf_ctx())
1058		return;
1059
1060	lock_sock(sk);
1061}
1062EXPORT_SYMBOL(sockopt_lock_sock);
1063
1064void sockopt_release_sock(struct sock *sk)
1065{
1066	if (has_current_bpf_ctx())
1067		return;
1068
1069	release_sock(sk);
1070}
1071EXPORT_SYMBOL(sockopt_release_sock);
1072
1073bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1074{
1075	return has_current_bpf_ctx() || ns_capable(ns, cap);
1076}
1077EXPORT_SYMBOL(sockopt_ns_capable);
1078
1079bool sockopt_capable(int cap)
1080{
1081	return has_current_bpf_ctx() || capable(cap);
1082}
1083EXPORT_SYMBOL(sockopt_capable);
1084
1085/*
1086 *	This is meant for all protocols to use and covers goings on
1087 *	at the socket level. Everything here is generic.
1088 */
1089
1090int sk_setsockopt(struct sock *sk, int level, int optname,
1091		  sockptr_t optval, unsigned int optlen)
1092{
1093	struct so_timestamping timestamping;
1094	struct socket *sock = sk->sk_socket;
1095	struct sock_txtime sk_txtime;
1096	int val;
1097	int valbool;
1098	struct linger ling;
1099	int ret = 0;
1100
1101	/*
1102	 *	Options without arguments
1103	 */
1104
1105	if (optname == SO_BINDTODEVICE)
1106		return sock_setbindtodevice(sk, optval, optlen);
1107
1108	if (optlen < sizeof(int))
1109		return -EINVAL;
1110
1111	if (copy_from_sockptr(&val, optval, sizeof(val)))
1112		return -EFAULT;
1113
1114	valbool = val ? 1 : 0;
1115
1116	/* handle options which do not require locking the socket. */
1117	switch (optname) {
1118	case SO_PRIORITY:
1119		if ((val >= 0 && val <= 6) ||
1120		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1121		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1122			sock_set_priority(sk, val);
1123			return 0;
1124		}
1125		return -EPERM;
1126	case SO_PASSSEC:
1127		assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1128		return 0;
1129	case SO_PASSCRED:
1130		assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1131		return 0;
1132	case SO_PASSPIDFD:
1133		assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1134		return 0;
1135	case SO_TYPE:
1136	case SO_PROTOCOL:
1137	case SO_DOMAIN:
1138	case SO_ERROR:
1139		return -ENOPROTOOPT;
1140#ifdef CONFIG_NET_RX_BUSY_POLL
1141	case SO_BUSY_POLL:
1142		if (val < 0)
1143			return -EINVAL;
1144		WRITE_ONCE(sk->sk_ll_usec, val);
1145		return 0;
1146	case SO_PREFER_BUSY_POLL:
1147		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1148			return -EPERM;
1149		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1150		return 0;
1151	case SO_BUSY_POLL_BUDGET:
1152		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1153		    !sockopt_capable(CAP_NET_ADMIN))
1154			return -EPERM;
1155		if (val < 0 || val > U16_MAX)
1156			return -EINVAL;
1157		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1158		return 0;
1159#endif
1160	case SO_MAX_PACING_RATE:
1161		{
1162		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1163		unsigned long pacing_rate;
1164
1165		if (sizeof(ulval) != sizeof(val) &&
1166		    optlen >= sizeof(ulval) &&
1167		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1168			return -EFAULT;
1169		}
1170		if (ulval != ~0UL)
1171			cmpxchg(&sk->sk_pacing_status,
1172				SK_PACING_NONE,
1173				SK_PACING_NEEDED);
1174		/* Pairs with READ_ONCE() from sk_getsockopt() */
1175		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1176		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1177		if (ulval < pacing_rate)
1178			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1179		return 0;
1180		}
1181	case SO_TXREHASH:
1182		if (val < -1 || val > 1)
1183			return -EINVAL;
1184		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1185			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1186		/* Paired with READ_ONCE() in tcp_rtx_synack()
1187		 * and sk_getsockopt().
1188		 */
1189		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1190		return 0;
1191	case SO_PEEK_OFF:
1192		{
1193		int (*set_peek_off)(struct sock *sk, int val);
1194
1195		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1196		if (set_peek_off)
1197			ret = set_peek_off(sk, val);
1198		else
1199			ret = -EOPNOTSUPP;
1200		return ret;
1201		}
1202	}
1203
1204	sockopt_lock_sock(sk);
1205
1206	switch (optname) {
1207	case SO_DEBUG:
1208		if (val && !sockopt_capable(CAP_NET_ADMIN))
1209			ret = -EACCES;
1210		else
1211			sock_valbool_flag(sk, SOCK_DBG, valbool);
1212		break;
1213	case SO_REUSEADDR:
1214		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1215		break;
1216	case SO_REUSEPORT:
1217		sk->sk_reuseport = valbool;
1218		break;
 
 
 
 
 
 
1219	case SO_DONTROUTE:
1220		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1221		sk_dst_reset(sk);
1222		break;
1223	case SO_BROADCAST:
1224		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1225		break;
1226	case SO_SNDBUF:
1227		/* Don't error on this BSD doesn't and if you think
1228		 * about it this is right. Otherwise apps have to
1229		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1230		 * are treated in BSD as hints
1231		 */
1232		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1233set_sndbuf:
1234		/* Ensure val * 2 fits into an int, to prevent max_t()
1235		 * from treating it as a negative value.
1236		 */
1237		val = min_t(int, val, INT_MAX / 2);
1238		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1239		WRITE_ONCE(sk->sk_sndbuf,
1240			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1241		/* Wake up sending tasks if we upped the value. */
1242		sk->sk_write_space(sk);
1243		break;
1244
1245	case SO_SNDBUFFORCE:
1246		if (!sockopt_capable(CAP_NET_ADMIN)) {
1247			ret = -EPERM;
1248			break;
1249		}
1250
1251		/* No negative values (to prevent underflow, as val will be
1252		 * multiplied by 2).
1253		 */
1254		if (val < 0)
1255			val = 0;
1256		goto set_sndbuf;
1257
1258	case SO_RCVBUF:
1259		/* Don't error on this BSD doesn't and if you think
1260		 * about it this is right. Otherwise apps have to
1261		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1262		 * are treated in BSD as hints
1263		 */
1264		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1265		break;
1266
1267	case SO_RCVBUFFORCE:
1268		if (!sockopt_capable(CAP_NET_ADMIN)) {
1269			ret = -EPERM;
1270			break;
1271		}
1272
1273		/* No negative values (to prevent underflow, as val will be
1274		 * multiplied by 2).
1275		 */
1276		__sock_set_rcvbuf(sk, max(val, 0));
1277		break;
1278
1279	case SO_KEEPALIVE:
1280		if (sk->sk_prot->keepalive)
1281			sk->sk_prot->keepalive(sk, valbool);
1282		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1283		break;
1284
1285	case SO_OOBINLINE:
1286		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1287		break;
1288
1289	case SO_NO_CHECK:
1290		sk->sk_no_check_tx = valbool;
1291		break;
1292
 
 
 
 
 
 
 
 
 
1293	case SO_LINGER:
1294		if (optlen < sizeof(ling)) {
1295			ret = -EINVAL;	/* 1003.1g */
1296			break;
1297		}
1298		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1299			ret = -EFAULT;
1300			break;
1301		}
1302		if (!ling.l_onoff) {
1303			sock_reset_flag(sk, SOCK_LINGER);
1304		} else {
1305			unsigned long t_sec = ling.l_linger;
1306
1307			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1308				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1309			else
1310				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
 
1311			sock_set_flag(sk, SOCK_LINGER);
1312		}
1313		break;
1314
1315	case SO_BSDCOMPAT:
1316		break;
1317
 
 
 
 
 
 
 
1318	case SO_TIMESTAMP_OLD:
1319	case SO_TIMESTAMP_NEW:
1320	case SO_TIMESTAMPNS_OLD:
1321	case SO_TIMESTAMPNS_NEW:
1322		sock_set_timestamp(sk, optname, valbool);
1323		break;
1324
1325	case SO_TIMESTAMPING_NEW:
1326	case SO_TIMESTAMPING_OLD:
1327		if (optlen == sizeof(timestamping)) {
1328			if (copy_from_sockptr(&timestamping, optval,
1329					      sizeof(timestamping))) {
1330				ret = -EFAULT;
1331				break;
1332			}
1333		} else {
1334			memset(&timestamping, 0, sizeof(timestamping));
1335			timestamping.flags = val;
1336		}
1337		ret = sock_set_timestamping(sk, optname, timestamping);
1338		break;
1339
1340	case SO_RCVLOWAT:
1341		{
1342		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1343
1344		if (val < 0)
1345			val = INT_MAX;
1346		if (sock)
1347			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1348		if (set_rcvlowat)
1349			ret = set_rcvlowat(sk, val);
1350		else
1351			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1352		break;
1353		}
1354	case SO_RCVTIMEO_OLD:
1355	case SO_RCVTIMEO_NEW:
1356		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1357				       optlen, optname == SO_RCVTIMEO_OLD);
1358		break;
1359
1360	case SO_SNDTIMEO_OLD:
1361	case SO_SNDTIMEO_NEW:
1362		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1363				       optlen, optname == SO_SNDTIMEO_OLD);
1364		break;
1365
1366	case SO_ATTACH_FILTER: {
1367		struct sock_fprog fprog;
1368
1369		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1370		if (!ret)
1371			ret = sk_attach_filter(&fprog, sk);
1372		break;
1373	}
1374	case SO_ATTACH_BPF:
1375		ret = -EINVAL;
1376		if (optlen == sizeof(u32)) {
1377			u32 ufd;
1378
1379			ret = -EFAULT;
1380			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1381				break;
1382
1383			ret = sk_attach_bpf(ufd, sk);
1384		}
1385		break;
1386
1387	case SO_ATTACH_REUSEPORT_CBPF: {
1388		struct sock_fprog fprog;
1389
1390		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1391		if (!ret)
1392			ret = sk_reuseport_attach_filter(&fprog, sk);
1393		break;
1394	}
1395	case SO_ATTACH_REUSEPORT_EBPF:
1396		ret = -EINVAL;
1397		if (optlen == sizeof(u32)) {
1398			u32 ufd;
1399
1400			ret = -EFAULT;
1401			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1402				break;
1403
1404			ret = sk_reuseport_attach_bpf(ufd, sk);
1405		}
1406		break;
1407
1408	case SO_DETACH_REUSEPORT_BPF:
1409		ret = reuseport_detach_prog(sk);
1410		break;
1411
1412	case SO_DETACH_FILTER:
1413		ret = sk_detach_filter(sk);
1414		break;
1415
1416	case SO_LOCK_FILTER:
1417		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1418			ret = -EPERM;
1419		else
1420			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1421		break;
1422
 
 
 
 
 
 
1423	case SO_MARK:
1424		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1425		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1426			ret = -EPERM;
1427			break;
1428		}
1429
1430		__sock_set_mark(sk, val);
1431		break;
1432	case SO_RCVMARK:
 
 
 
 
 
 
1433		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1434		break;
1435
1436	case SO_RXQ_OVFL:
1437		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1438		break;
1439
1440	case SO_WIFI_STATUS:
1441		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1442		break;
1443
 
 
 
 
 
 
 
1444	case SO_NOFCS:
1445		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1446		break;
1447
1448	case SO_SELECT_ERR_QUEUE:
1449		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1450		break;
1451
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1452
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1453	case SO_INCOMING_CPU:
1454		reuseport_update_incoming_cpu(sk, val);
1455		break;
1456
1457	case SO_CNX_ADVICE:
1458		if (val == 1)
1459			dst_negative_advice(sk);
1460		break;
1461
1462	case SO_ZEROCOPY:
1463		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1464			if (!(sk_is_tcp(sk) ||
1465			      (sk->sk_type == SOCK_DGRAM &&
1466			       sk->sk_protocol == IPPROTO_UDP)))
1467				ret = -EOPNOTSUPP;
1468		} else if (sk->sk_family != PF_RDS) {
1469			ret = -EOPNOTSUPP;
1470		}
1471		if (!ret) {
1472			if (val < 0 || val > 1)
1473				ret = -EINVAL;
1474			else
1475				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1476		}
1477		break;
1478
1479	case SO_TXTIME:
1480		if (optlen != sizeof(struct sock_txtime)) {
1481			ret = -EINVAL;
1482			break;
1483		} else if (copy_from_sockptr(&sk_txtime, optval,
1484			   sizeof(struct sock_txtime))) {
1485			ret = -EFAULT;
1486			break;
1487		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1488			ret = -EINVAL;
1489			break;
1490		}
1491		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1492		 * scheduler has enough safe guards.
1493		 */
1494		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1495		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1496			ret = -EPERM;
1497			break;
1498		}
1499		sock_valbool_flag(sk, SOCK_TXTIME, true);
1500		sk->sk_clockid = sk_txtime.clockid;
1501		sk->sk_txtime_deadline_mode =
1502			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1503		sk->sk_txtime_report_errors =
1504			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1505		break;
1506
1507	case SO_BINDTOIFINDEX:
1508		ret = sock_bindtoindex_locked(sk, val);
1509		break;
1510
1511	case SO_BUF_LOCK:
1512		if (val & ~SOCK_BUF_LOCK_MASK) {
1513			ret = -EINVAL;
1514			break;
1515		}
1516		sk->sk_userlocks = val | (sk->sk_userlocks &
1517					  ~SOCK_BUF_LOCK_MASK);
1518		break;
1519
1520	case SO_RESERVE_MEM:
1521	{
1522		int delta;
1523
1524		if (val < 0) {
1525			ret = -EINVAL;
1526			break;
1527		}
1528
1529		delta = val - sk->sk_reserved_mem;
1530		if (delta < 0)
1531			sock_release_reserved_memory(sk, -delta);
1532		else
1533			ret = sock_reserve_memory(sk, delta);
1534		break;
1535	}
1536
 
 
 
 
 
 
 
 
 
 
 
1537	default:
1538		ret = -ENOPROTOOPT;
1539		break;
1540	}
1541	sockopt_release_sock(sk);
1542	return ret;
1543}
1544
1545int sock_setsockopt(struct socket *sock, int level, int optname,
1546		    sockptr_t optval, unsigned int optlen)
1547{
1548	return sk_setsockopt(sock->sk, level, optname,
1549			     optval, optlen);
1550}
1551EXPORT_SYMBOL(sock_setsockopt);
1552
1553static const struct cred *sk_get_peer_cred(struct sock *sk)
1554{
1555	const struct cred *cred;
1556
1557	spin_lock(&sk->sk_peer_lock);
1558	cred = get_cred(sk->sk_peer_cred);
1559	spin_unlock(&sk->sk_peer_lock);
1560
1561	return cred;
1562}
1563
1564static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1565			  struct ucred *ucred)
1566{
1567	ucred->pid = pid_vnr(pid);
1568	ucred->uid = ucred->gid = -1;
1569	if (cred) {
1570		struct user_namespace *current_ns = current_user_ns();
1571
1572		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1573		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1574	}
1575}
1576
1577static int groups_to_user(sockptr_t dst, const struct group_info *src)
1578{
1579	struct user_namespace *user_ns = current_user_ns();
1580	int i;
1581
1582	for (i = 0; i < src->ngroups; i++) {
1583		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1584
1585		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1586			return -EFAULT;
1587	}
1588
1589	return 0;
1590}
1591
1592int sk_getsockopt(struct sock *sk, int level, int optname,
1593		  sockptr_t optval, sockptr_t optlen)
1594{
1595	struct socket *sock = sk->sk_socket;
1596
1597	union {
1598		int val;
1599		u64 val64;
1600		unsigned long ulval;
1601		struct linger ling;
1602		struct old_timeval32 tm32;
1603		struct __kernel_old_timeval tm;
1604		struct  __kernel_sock_timeval stm;
1605		struct sock_txtime txtime;
1606		struct so_timestamping timestamping;
1607	} v;
1608
1609	int lv = sizeof(int);
1610	int len;
1611
1612	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1613		return -EFAULT;
1614	if (len < 0)
1615		return -EINVAL;
1616
1617	memset(&v, 0, sizeof(v));
1618
1619	switch (optname) {
1620	case SO_DEBUG:
1621		v.val = sock_flag(sk, SOCK_DBG);
1622		break;
1623
1624	case SO_DONTROUTE:
1625		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1626		break;
1627
1628	case SO_BROADCAST:
1629		v.val = sock_flag(sk, SOCK_BROADCAST);
1630		break;
1631
1632	case SO_SNDBUF:
1633		v.val = READ_ONCE(sk->sk_sndbuf);
1634		break;
1635
1636	case SO_RCVBUF:
1637		v.val = READ_ONCE(sk->sk_rcvbuf);
1638		break;
1639
1640	case SO_REUSEADDR:
1641		v.val = sk->sk_reuse;
1642		break;
1643
1644	case SO_REUSEPORT:
1645		v.val = sk->sk_reuseport;
1646		break;
1647
1648	case SO_KEEPALIVE:
1649		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1650		break;
1651
1652	case SO_TYPE:
1653		v.val = sk->sk_type;
1654		break;
1655
1656	case SO_PROTOCOL:
1657		v.val = sk->sk_protocol;
1658		break;
1659
1660	case SO_DOMAIN:
1661		v.val = sk->sk_family;
1662		break;
1663
1664	case SO_ERROR:
1665		v.val = -sock_error(sk);
1666		if (v.val == 0)
1667			v.val = xchg(&sk->sk_err_soft, 0);
1668		break;
1669
1670	case SO_OOBINLINE:
1671		v.val = sock_flag(sk, SOCK_URGINLINE);
1672		break;
1673
1674	case SO_NO_CHECK:
1675		v.val = sk->sk_no_check_tx;
1676		break;
1677
1678	case SO_PRIORITY:
1679		v.val = READ_ONCE(sk->sk_priority);
1680		break;
1681
1682	case SO_LINGER:
1683		lv		= sizeof(v.ling);
1684		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1685		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1686		break;
1687
1688	case SO_BSDCOMPAT:
1689		break;
1690
1691	case SO_TIMESTAMP_OLD:
1692		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1693				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1694				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1695		break;
1696
1697	case SO_TIMESTAMPNS_OLD:
1698		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1699		break;
1700
1701	case SO_TIMESTAMP_NEW:
1702		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1703		break;
1704
1705	case SO_TIMESTAMPNS_NEW:
1706		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1707		break;
1708
1709	case SO_TIMESTAMPING_OLD:
1710	case SO_TIMESTAMPING_NEW:
1711		lv = sizeof(v.timestamping);
1712		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1713		 * returning the flags when they were set through the same option.
1714		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1715		 */
1716		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1717			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1718			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1719		}
1720		break;
1721
1722	case SO_RCVTIMEO_OLD:
1723	case SO_RCVTIMEO_NEW:
1724		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1725				      SO_RCVTIMEO_OLD == optname);
1726		break;
1727
1728	case SO_SNDTIMEO_OLD:
1729	case SO_SNDTIMEO_NEW:
1730		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1731				      SO_SNDTIMEO_OLD == optname);
1732		break;
1733
1734	case SO_RCVLOWAT:
1735		v.val = READ_ONCE(sk->sk_rcvlowat);
1736		break;
1737
1738	case SO_SNDLOWAT:
1739		v.val = 1;
1740		break;
1741
1742	case SO_PASSCRED:
1743		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1744		break;
1745
1746	case SO_PASSPIDFD:
1747		v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1748		break;
1749
1750	case SO_PEERCRED:
1751	{
1752		struct ucred peercred;
1753		if (len > sizeof(peercred))
1754			len = sizeof(peercred);
1755
1756		spin_lock(&sk->sk_peer_lock);
1757		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1758		spin_unlock(&sk->sk_peer_lock);
1759
1760		if (copy_to_sockptr(optval, &peercred, len))
1761			return -EFAULT;
1762		goto lenout;
1763	}
1764
1765	case SO_PEERPIDFD:
1766	{
1767		struct pid *peer_pid;
1768		struct file *pidfd_file = NULL;
1769		int pidfd;
1770
1771		if (len > sizeof(pidfd))
1772			len = sizeof(pidfd);
1773
1774		spin_lock(&sk->sk_peer_lock);
1775		peer_pid = get_pid(sk->sk_peer_pid);
1776		spin_unlock(&sk->sk_peer_lock);
1777
1778		if (!peer_pid)
1779			return -ENODATA;
1780
1781		pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file);
1782		put_pid(peer_pid);
1783		if (pidfd < 0)
1784			return pidfd;
1785
1786		if (copy_to_sockptr(optval, &pidfd, len) ||
1787		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1788			put_unused_fd(pidfd);
1789			fput(pidfd_file);
1790
1791			return -EFAULT;
1792		}
1793
1794		fd_install(pidfd, pidfd_file);
1795		return 0;
1796	}
1797
1798	case SO_PEERGROUPS:
1799	{
1800		const struct cred *cred;
1801		int ret, n;
1802
1803		cred = sk_get_peer_cred(sk);
1804		if (!cred)
1805			return -ENODATA;
1806
1807		n = cred->group_info->ngroups;
1808		if (len < n * sizeof(gid_t)) {
1809			len = n * sizeof(gid_t);
1810			put_cred(cred);
1811			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1812		}
1813		len = n * sizeof(gid_t);
1814
1815		ret = groups_to_user(optval, cred->group_info);
1816		put_cred(cred);
1817		if (ret)
1818			return ret;
1819		goto lenout;
1820	}
1821
1822	case SO_PEERNAME:
1823	{
1824		struct sockaddr_storage address;
1825
1826		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1827		if (lv < 0)
1828			return -ENOTCONN;
1829		if (lv < len)
1830			return -EINVAL;
1831		if (copy_to_sockptr(optval, &address, len))
1832			return -EFAULT;
1833		goto lenout;
1834	}
1835
1836	/* Dubious BSD thing... Probably nobody even uses it, but
1837	 * the UNIX standard wants it for whatever reason... -DaveM
1838	 */
1839	case SO_ACCEPTCONN:
1840		v.val = sk->sk_state == TCP_LISTEN;
1841		break;
1842
1843	case SO_PASSSEC:
1844		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1845		break;
1846
1847	case SO_PEERSEC:
1848		return security_socket_getpeersec_stream(sock,
1849							 optval, optlen, len);
1850
1851	case SO_MARK:
1852		v.val = READ_ONCE(sk->sk_mark);
1853		break;
1854
1855	case SO_RCVMARK:
1856		v.val = sock_flag(sk, SOCK_RCVMARK);
1857		break;
1858
1859	case SO_RXQ_OVFL:
1860		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1861		break;
1862
1863	case SO_WIFI_STATUS:
1864		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1865		break;
1866
1867	case SO_PEEK_OFF:
1868		if (!READ_ONCE(sock->ops)->set_peek_off)
1869			return -EOPNOTSUPP;
1870
1871		v.val = READ_ONCE(sk->sk_peek_off);
1872		break;
1873	case SO_NOFCS:
1874		v.val = sock_flag(sk, SOCK_NOFCS);
1875		break;
1876
1877	case SO_BINDTODEVICE:
1878		return sock_getbindtodevice(sk, optval, optlen, len);
1879
1880	case SO_GET_FILTER:
1881		len = sk_get_filter(sk, optval, len);
1882		if (len < 0)
1883			return len;
1884
1885		goto lenout;
1886
1887	case SO_LOCK_FILTER:
1888		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1889		break;
1890
1891	case SO_BPF_EXTENSIONS:
1892		v.val = bpf_tell_extensions();
1893		break;
1894
1895	case SO_SELECT_ERR_QUEUE:
1896		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1897		break;
1898
1899#ifdef CONFIG_NET_RX_BUSY_POLL
1900	case SO_BUSY_POLL:
1901		v.val = READ_ONCE(sk->sk_ll_usec);
1902		break;
1903	case SO_PREFER_BUSY_POLL:
1904		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1905		break;
1906#endif
1907
1908	case SO_MAX_PACING_RATE:
1909		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
1910		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1911			lv = sizeof(v.ulval);
1912			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
1913		} else {
1914			/* 32bit version */
1915			v.val = min_t(unsigned long, ~0U,
1916				      READ_ONCE(sk->sk_max_pacing_rate));
1917		}
1918		break;
1919
1920	case SO_INCOMING_CPU:
1921		v.val = READ_ONCE(sk->sk_incoming_cpu);
1922		break;
1923
1924	case SO_MEMINFO:
1925	{
1926		u32 meminfo[SK_MEMINFO_VARS];
1927
1928		sk_get_meminfo(sk, meminfo);
1929
1930		len = min_t(unsigned int, len, sizeof(meminfo));
1931		if (copy_to_sockptr(optval, &meminfo, len))
1932			return -EFAULT;
1933
1934		goto lenout;
1935	}
1936
1937#ifdef CONFIG_NET_RX_BUSY_POLL
1938	case SO_INCOMING_NAPI_ID:
1939		v.val = READ_ONCE(sk->sk_napi_id);
1940
1941		/* aggregate non-NAPI IDs down to 0 */
1942		if (v.val < MIN_NAPI_ID)
1943			v.val = 0;
1944
1945		break;
1946#endif
1947
1948	case SO_COOKIE:
1949		lv = sizeof(u64);
1950		if (len < lv)
1951			return -EINVAL;
1952		v.val64 = sock_gen_cookie(sk);
1953		break;
1954
1955	case SO_ZEROCOPY:
1956		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1957		break;
1958
1959	case SO_TXTIME:
1960		lv = sizeof(v.txtime);
1961		v.txtime.clockid = sk->sk_clockid;
1962		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1963				  SOF_TXTIME_DEADLINE_MODE : 0;
1964		v.txtime.flags |= sk->sk_txtime_report_errors ?
1965				  SOF_TXTIME_REPORT_ERRORS : 0;
1966		break;
1967
1968	case SO_BINDTOIFINDEX:
1969		v.val = READ_ONCE(sk->sk_bound_dev_if);
1970		break;
1971
1972	case SO_NETNS_COOKIE:
1973		lv = sizeof(u64);
1974		if (len != lv)
1975			return -EINVAL;
1976		v.val64 = sock_net(sk)->net_cookie;
1977		break;
1978
1979	case SO_BUF_LOCK:
1980		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1981		break;
1982
1983	case SO_RESERVE_MEM:
1984		v.val = READ_ONCE(sk->sk_reserved_mem);
1985		break;
1986
1987	case SO_TXREHASH:
1988		/* Paired with WRITE_ONCE() in sk_setsockopt() */
1989		v.val = READ_ONCE(sk->sk_txrehash);
1990		break;
1991
1992	default:
1993		/* We implement the SO_SNDLOWAT etc to not be settable
1994		 * (1003.1g 7).
1995		 */
1996		return -ENOPROTOOPT;
1997	}
1998
1999	if (len > lv)
2000		len = lv;
2001	if (copy_to_sockptr(optval, &v, len))
2002		return -EFAULT;
2003lenout:
2004	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2005		return -EFAULT;
2006	return 0;
2007}
2008
 
 
 
 
 
 
 
 
2009/*
2010 * Initialize an sk_lock.
2011 *
2012 * (We also register the sk_lock with the lock validator.)
2013 */
2014static inline void sock_lock_init(struct sock *sk)
2015{
2016	if (sk->sk_kern_sock)
2017		sock_lock_init_class_and_name(
2018			sk,
2019			af_family_kern_slock_key_strings[sk->sk_family],
2020			af_family_kern_slock_keys + sk->sk_family,
2021			af_family_kern_key_strings[sk->sk_family],
2022			af_family_kern_keys + sk->sk_family);
2023	else
2024		sock_lock_init_class_and_name(
2025			sk,
2026			af_family_slock_key_strings[sk->sk_family],
2027			af_family_slock_keys + sk->sk_family,
2028			af_family_key_strings[sk->sk_family],
2029			af_family_keys + sk->sk_family);
2030}
2031
2032/*
2033 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2034 * even temporarly, because of RCU lookups. sk_node should also be left as is.
2035 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2036 */
2037static void sock_copy(struct sock *nsk, const struct sock *osk)
2038{
2039	const struct proto *prot = READ_ONCE(osk->sk_prot);
2040#ifdef CONFIG_SECURITY_NETWORK
2041	void *sptr = nsk->sk_security;
2042#endif
2043
2044	/* If we move sk_tx_queue_mapping out of the private section,
2045	 * we must check if sk_tx_queue_clear() is called after
2046	 * sock_copy() in sk_clone_lock().
2047	 */
2048	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2049		     offsetof(struct sock, sk_dontcopy_begin) ||
2050		     offsetof(struct sock, sk_tx_queue_mapping) >=
2051		     offsetof(struct sock, sk_dontcopy_end));
2052
2053	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2054
2055	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2056	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2057
2058#ifdef CONFIG_SECURITY_NETWORK
2059	nsk->sk_security = sptr;
2060	security_sk_clone(osk, nsk);
2061#endif
2062}
2063
2064static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2065		int family)
2066{
2067	struct sock *sk;
2068	struct kmem_cache *slab;
2069
2070	slab = prot->slab;
2071	if (slab != NULL) {
2072		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2073		if (!sk)
2074			return sk;
2075		if (want_init_on_alloc(priority))
2076			sk_prot_clear_nulls(sk, prot->obj_size);
2077	} else
2078		sk = kmalloc(prot->obj_size, priority);
2079
2080	if (sk != NULL) {
2081		if (security_sk_alloc(sk, family, priority))
2082			goto out_free;
2083
2084		if (!try_module_get(prot->owner))
2085			goto out_free_sec;
2086	}
2087
2088	return sk;
2089
2090out_free_sec:
2091	security_sk_free(sk);
2092out_free:
2093	if (slab != NULL)
2094		kmem_cache_free(slab, sk);
2095	else
2096		kfree(sk);
2097	return NULL;
2098}
2099
2100static void sk_prot_free(struct proto *prot, struct sock *sk)
2101{
2102	struct kmem_cache *slab;
2103	struct module *owner;
2104
2105	owner = prot->owner;
2106	slab = prot->slab;
2107
2108	cgroup_sk_free(&sk->sk_cgrp_data);
2109	mem_cgroup_sk_free(sk);
2110	security_sk_free(sk);
2111	if (slab != NULL)
2112		kmem_cache_free(slab, sk);
2113	else
2114		kfree(sk);
2115	module_put(owner);
2116}
2117
2118/**
2119 *	sk_alloc - All socket objects are allocated here
2120 *	@net: the applicable net namespace
2121 *	@family: protocol family
2122 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2123 *	@prot: struct proto associated with this new sock instance
2124 *	@kern: is this to be a kernel socket?
2125 */
2126struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2127		      struct proto *prot, int kern)
2128{
2129	struct sock *sk;
2130
2131	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2132	if (sk) {
2133		sk->sk_family = family;
2134		/*
2135		 * See comment in struct sock definition to understand
2136		 * why we need sk_prot_creator -acme
2137		 */
2138		sk->sk_prot = sk->sk_prot_creator = prot;
2139		sk->sk_kern_sock = kern;
2140		sock_lock_init(sk);
2141		sk->sk_net_refcnt = kern ? 0 : 1;
2142		if (likely(sk->sk_net_refcnt)) {
2143			get_net_track(net, &sk->ns_tracker, priority);
2144			sock_inuse_add(net, 1);
2145		} else {
2146			__netns_tracker_alloc(net, &sk->ns_tracker,
2147					      false, priority);
2148		}
2149
2150		sock_net_set(sk, net);
2151		refcount_set(&sk->sk_wmem_alloc, 1);
2152
2153		mem_cgroup_sk_alloc(sk);
2154		cgroup_sk_alloc(&sk->sk_cgrp_data);
2155		sock_update_classid(&sk->sk_cgrp_data);
2156		sock_update_netprioidx(&sk->sk_cgrp_data);
2157		sk_tx_queue_clear(sk);
2158	}
2159
2160	return sk;
2161}
2162EXPORT_SYMBOL(sk_alloc);
2163
2164/* Sockets having SOCK_RCU_FREE will call this function after one RCU
2165 * grace period. This is the case for UDP sockets and TCP listeners.
2166 */
2167static void __sk_destruct(struct rcu_head *head)
2168{
2169	struct sock *sk = container_of(head, struct sock, sk_rcu);
2170	struct sk_filter *filter;
2171
2172	if (sk->sk_destruct)
2173		sk->sk_destruct(sk);
2174
2175	filter = rcu_dereference_check(sk->sk_filter,
2176				       refcount_read(&sk->sk_wmem_alloc) == 0);
2177	if (filter) {
2178		sk_filter_uncharge(sk, filter);
2179		RCU_INIT_POINTER(sk->sk_filter, NULL);
2180	}
2181
2182	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2183
2184#ifdef CONFIG_BPF_SYSCALL
2185	bpf_sk_storage_free(sk);
2186#endif
2187
2188	if (atomic_read(&sk->sk_omem_alloc))
2189		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2190			 __func__, atomic_read(&sk->sk_omem_alloc));
2191
2192	if (sk->sk_frag.page) {
2193		put_page(sk->sk_frag.page);
2194		sk->sk_frag.page = NULL;
2195	}
2196
2197	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2198	put_cred(sk->sk_peer_cred);
2199	put_pid(sk->sk_peer_pid);
2200
2201	if (likely(sk->sk_net_refcnt))
2202		put_net_track(sock_net(sk), &sk->ns_tracker);
2203	else
2204		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2205
2206	sk_prot_free(sk->sk_prot_creator, sk);
2207}
2208
2209void sk_destruct(struct sock *sk)
2210{
2211	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2212
2213	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2214		reuseport_detach_sock(sk);
2215		use_call_rcu = true;
2216	}
2217
2218	if (use_call_rcu)
2219		call_rcu(&sk->sk_rcu, __sk_destruct);
2220	else
2221		__sk_destruct(&sk->sk_rcu);
2222}
2223
2224static void __sk_free(struct sock *sk)
2225{
2226	if (likely(sk->sk_net_refcnt))
2227		sock_inuse_add(sock_net(sk), -1);
2228
2229	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2230		sock_diag_broadcast_destroy(sk);
2231	else
2232		sk_destruct(sk);
2233}
2234
2235void sk_free(struct sock *sk)
2236{
2237	/*
2238	 * We subtract one from sk_wmem_alloc and can know if
2239	 * some packets are still in some tx queue.
2240	 * If not null, sock_wfree() will call __sk_free(sk) later
2241	 */
2242	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2243		__sk_free(sk);
2244}
2245EXPORT_SYMBOL(sk_free);
2246
2247static void sk_init_common(struct sock *sk)
2248{
2249	skb_queue_head_init(&sk->sk_receive_queue);
2250	skb_queue_head_init(&sk->sk_write_queue);
2251	skb_queue_head_init(&sk->sk_error_queue);
2252
2253	rwlock_init(&sk->sk_callback_lock);
2254	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2255			af_rlock_keys + sk->sk_family,
2256			af_family_rlock_key_strings[sk->sk_family]);
2257	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2258			af_wlock_keys + sk->sk_family,
2259			af_family_wlock_key_strings[sk->sk_family]);
2260	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2261			af_elock_keys + sk->sk_family,
2262			af_family_elock_key_strings[sk->sk_family]);
2263	lockdep_set_class_and_name(&sk->sk_callback_lock,
2264			af_callback_keys + sk->sk_family,
2265			af_family_clock_key_strings[sk->sk_family]);
2266}
2267
2268/**
2269 *	sk_clone_lock - clone a socket, and lock its clone
2270 *	@sk: the socket to clone
2271 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2272 *
2273 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2274 */
2275struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2276{
2277	struct proto *prot = READ_ONCE(sk->sk_prot);
2278	struct sk_filter *filter;
2279	bool is_charged = true;
2280	struct sock *newsk;
2281
2282	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2283	if (!newsk)
2284		goto out;
2285
2286	sock_copy(newsk, sk);
2287
2288	newsk->sk_prot_creator = prot;
2289
2290	/* SANITY */
2291	if (likely(newsk->sk_net_refcnt)) {
2292		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2293		sock_inuse_add(sock_net(newsk), 1);
2294	} else {
2295		/* Kernel sockets are not elevating the struct net refcount.
2296		 * Instead, use a tracker to more easily detect if a layer
2297		 * is not properly dismantling its kernel sockets at netns
2298		 * destroy time.
2299		 */
2300		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2301				      false, priority);
2302	}
2303	sk_node_init(&newsk->sk_node);
2304	sock_lock_init(newsk);
2305	bh_lock_sock(newsk);
2306	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2307	newsk->sk_backlog.len = 0;
2308
2309	atomic_set(&newsk->sk_rmem_alloc, 0);
2310
2311	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2312	refcount_set(&newsk->sk_wmem_alloc, 1);
2313
2314	atomic_set(&newsk->sk_omem_alloc, 0);
2315	sk_init_common(newsk);
2316
2317	newsk->sk_dst_cache	= NULL;
2318	newsk->sk_dst_pending_confirm = 0;
2319	newsk->sk_wmem_queued	= 0;
2320	newsk->sk_forward_alloc = 0;
2321	newsk->sk_reserved_mem  = 0;
2322	atomic_set(&newsk->sk_drops, 0);
2323	newsk->sk_send_head	= NULL;
2324	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2325	atomic_set(&newsk->sk_zckey, 0);
2326
2327	sock_reset_flag(newsk, SOCK_DONE);
2328
2329	/* sk->sk_memcg will be populated at accept() time */
2330	newsk->sk_memcg = NULL;
2331
2332	cgroup_sk_clone(&newsk->sk_cgrp_data);
2333
2334	rcu_read_lock();
2335	filter = rcu_dereference(sk->sk_filter);
2336	if (filter != NULL)
2337		/* though it's an empty new sock, the charging may fail
2338		 * if sysctl_optmem_max was changed between creation of
2339		 * original socket and cloning
2340		 */
2341		is_charged = sk_filter_charge(newsk, filter);
2342	RCU_INIT_POINTER(newsk->sk_filter, filter);
2343	rcu_read_unlock();
2344
2345	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2346		/* We need to make sure that we don't uncharge the new
2347		 * socket if we couldn't charge it in the first place
2348		 * as otherwise we uncharge the parent's filter.
2349		 */
2350		if (!is_charged)
2351			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2352		sk_free_unlock_clone(newsk);
2353		newsk = NULL;
2354		goto out;
2355	}
2356	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2357
2358	if (bpf_sk_storage_clone(sk, newsk)) {
2359		sk_free_unlock_clone(newsk);
2360		newsk = NULL;
2361		goto out;
2362	}
2363
2364	/* Clear sk_user_data if parent had the pointer tagged
2365	 * as not suitable for copying when cloning.
2366	 */
2367	if (sk_user_data_is_nocopy(newsk))
2368		newsk->sk_user_data = NULL;
2369
2370	newsk->sk_err	   = 0;
2371	newsk->sk_err_soft = 0;
2372	newsk->sk_priority = 0;
2373	newsk->sk_incoming_cpu = raw_smp_processor_id();
2374
2375	/* Before updating sk_refcnt, we must commit prior changes to memory
2376	 * (Documentation/RCU/rculist_nulls.rst for details)
2377	 */
2378	smp_wmb();
2379	refcount_set(&newsk->sk_refcnt, 2);
2380
 
 
 
 
 
 
 
 
 
 
 
2381	sk_set_socket(newsk, NULL);
2382	sk_tx_queue_clear(newsk);
2383	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2384
2385	if (newsk->sk_prot->sockets_allocated)
2386		sk_sockets_allocated_inc(newsk);
2387
2388	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2389		net_enable_timestamp();
2390out:
2391	return newsk;
2392}
2393EXPORT_SYMBOL_GPL(sk_clone_lock);
2394
2395void sk_free_unlock_clone(struct sock *sk)
2396{
2397	/* It is still raw copy of parent, so invalidate
2398	 * destructor and make plain sk_free() */
2399	sk->sk_destruct = NULL;
2400	bh_unlock_sock(sk);
2401	sk_free(sk);
2402}
2403EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2404
2405static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2406{
2407	bool is_ipv6 = false;
2408	u32 max_size;
2409
2410#if IS_ENABLED(CONFIG_IPV6)
2411	is_ipv6 = (sk->sk_family == AF_INET6 &&
2412		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
 
 
2413#endif
2414	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2415	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2416			READ_ONCE(dst->dev->gso_ipv4_max_size);
2417	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2418		max_size = GSO_LEGACY_MAX_SIZE;
2419
2420	return max_size - (MAX_TCP_HEADER + 1);
2421}
2422
2423void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2424{
2425	u32 max_segs = 1;
2426
 
2427	sk->sk_route_caps = dst->dev->features;
2428	if (sk_is_tcp(sk))
2429		sk->sk_route_caps |= NETIF_F_GSO;
2430	if (sk->sk_route_caps & NETIF_F_GSO)
2431		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2432	if (unlikely(sk->sk_gso_disabled))
2433		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2434	if (sk_can_gso(sk)) {
2435		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2436			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2437		} else {
2438			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2439			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
 
 
 
2440			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2441			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2442		}
2443	}
2444	sk->sk_gso_max_segs = max_segs;
2445	sk_dst_set(sk, dst);
2446}
2447EXPORT_SYMBOL_GPL(sk_setup_caps);
2448
2449/*
2450 *	Simple resource managers for sockets.
2451 */
2452
2453
2454/*
2455 * Write buffer destructor automatically called from kfree_skb.
2456 */
2457void sock_wfree(struct sk_buff *skb)
2458{
2459	struct sock *sk = skb->sk;
2460	unsigned int len = skb->truesize;
2461	bool free;
2462
2463	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2464		if (sock_flag(sk, SOCK_RCU_FREE) &&
2465		    sk->sk_write_space == sock_def_write_space) {
2466			rcu_read_lock();
2467			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2468			sock_def_write_space_wfree(sk);
2469			rcu_read_unlock();
2470			if (unlikely(free))
2471				__sk_free(sk);
2472			return;
2473		}
2474
2475		/*
2476		 * Keep a reference on sk_wmem_alloc, this will be released
2477		 * after sk_write_space() call
2478		 */
2479		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2480		sk->sk_write_space(sk);
2481		len = 1;
2482	}
2483	/*
2484	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2485	 * could not do because of in-flight packets
2486	 */
2487	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2488		__sk_free(sk);
2489}
2490EXPORT_SYMBOL(sock_wfree);
2491
2492/* This variant of sock_wfree() is used by TCP,
2493 * since it sets SOCK_USE_WRITE_QUEUE.
2494 */
2495void __sock_wfree(struct sk_buff *skb)
2496{
2497	struct sock *sk = skb->sk;
2498
2499	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2500		__sk_free(sk);
2501}
2502
2503void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2504{
2505	skb_orphan(skb);
2506	skb->sk = sk;
2507#ifdef CONFIG_INET
2508	if (unlikely(!sk_fullsock(sk))) {
2509		skb->destructor = sock_edemux;
2510		sock_hold(sk);
2511		return;
2512	}
2513#endif
2514	skb->destructor = sock_wfree;
2515	skb_set_hash_from_sk(skb, sk);
2516	/*
2517	 * We used to take a refcount on sk, but following operation
2518	 * is enough to guarantee sk_free() wont free this sock until
2519	 * all in-flight packets are completed
2520	 */
2521	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2522}
2523EXPORT_SYMBOL(skb_set_owner_w);
2524
2525static bool can_skb_orphan_partial(const struct sk_buff *skb)
2526{
2527#ifdef CONFIG_TLS_DEVICE
2528	/* Drivers depend on in-order delivery for crypto offload,
2529	 * partial orphan breaks out-of-order-OK logic.
2530	 */
2531	if (skb->decrypted)
2532		return false;
2533#endif
2534	return (skb->destructor == sock_wfree ||
2535		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2536}
2537
2538/* This helper is used by netem, as it can hold packets in its
2539 * delay queue. We want to allow the owner socket to send more
2540 * packets, as if they were already TX completed by a typical driver.
2541 * But we also want to keep skb->sk set because some packet schedulers
2542 * rely on it (sch_fq for example).
2543 */
2544void skb_orphan_partial(struct sk_buff *skb)
2545{
2546	if (skb_is_tcp_pure_ack(skb))
2547		return;
2548
2549	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2550		return;
2551
2552	skb_orphan(skb);
2553}
2554EXPORT_SYMBOL(skb_orphan_partial);
2555
2556/*
2557 * Read buffer destructor automatically called from kfree_skb.
2558 */
2559void sock_rfree(struct sk_buff *skb)
2560{
2561	struct sock *sk = skb->sk;
2562	unsigned int len = skb->truesize;
2563
2564	atomic_sub(len, &sk->sk_rmem_alloc);
2565	sk_mem_uncharge(sk, len);
2566}
2567EXPORT_SYMBOL(sock_rfree);
2568
2569/*
2570 * Buffer destructor for skbs that are not used directly in read or write
2571 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2572 */
2573void sock_efree(struct sk_buff *skb)
2574{
2575	sock_put(skb->sk);
2576}
2577EXPORT_SYMBOL(sock_efree);
2578
2579/* Buffer destructor for prefetch/receive path where reference count may
2580 * not be held, e.g. for listen sockets.
2581 */
2582#ifdef CONFIG_INET
2583void sock_pfree(struct sk_buff *skb)
2584{
2585	if (sk_is_refcounted(skb->sk))
2586		sock_gen_put(skb->sk);
2587}
2588EXPORT_SYMBOL(sock_pfree);
2589#endif /* CONFIG_INET */
2590
2591kuid_t sock_i_uid(struct sock *sk)
2592{
2593	kuid_t uid;
2594
2595	read_lock_bh(&sk->sk_callback_lock);
2596	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2597	read_unlock_bh(&sk->sk_callback_lock);
2598	return uid;
2599}
2600EXPORT_SYMBOL(sock_i_uid);
2601
2602unsigned long __sock_i_ino(struct sock *sk)
2603{
2604	unsigned long ino;
2605
2606	read_lock(&sk->sk_callback_lock);
2607	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2608	read_unlock(&sk->sk_callback_lock);
2609	return ino;
2610}
2611EXPORT_SYMBOL(__sock_i_ino);
2612
2613unsigned long sock_i_ino(struct sock *sk)
2614{
2615	unsigned long ino;
2616
2617	local_bh_disable();
2618	ino = __sock_i_ino(sk);
2619	local_bh_enable();
2620	return ino;
2621}
2622EXPORT_SYMBOL(sock_i_ino);
2623
2624/*
2625 * Allocate a skb from the socket's send buffer.
2626 */
2627struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2628			     gfp_t priority)
2629{
2630	if (force ||
2631	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2632		struct sk_buff *skb = alloc_skb(size, priority);
2633
2634		if (skb) {
2635			skb_set_owner_w(skb, sk);
2636			return skb;
2637		}
2638	}
2639	return NULL;
2640}
2641EXPORT_SYMBOL(sock_wmalloc);
2642
2643static void sock_ofree(struct sk_buff *skb)
2644{
2645	struct sock *sk = skb->sk;
2646
2647	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2648}
2649
2650struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2651			     gfp_t priority)
2652{
2653	struct sk_buff *skb;
2654
2655	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2656	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2657	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2658		return NULL;
2659
2660	skb = alloc_skb(size, priority);
2661	if (!skb)
2662		return NULL;
2663
2664	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2665	skb->sk = sk;
2666	skb->destructor = sock_ofree;
2667	return skb;
2668}
2669
2670/*
2671 * Allocate a memory block from the socket's option memory buffer.
2672 */
2673void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2674{
2675	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2676
2677	if ((unsigned int)size <= optmem_max &&
2678	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2679		void *mem;
2680		/* First do the add, to avoid the race if kmalloc
2681		 * might sleep.
2682		 */
2683		atomic_add(size, &sk->sk_omem_alloc);
2684		mem = kmalloc(size, priority);
2685		if (mem)
2686			return mem;
2687		atomic_sub(size, &sk->sk_omem_alloc);
2688	}
2689	return NULL;
2690}
2691EXPORT_SYMBOL(sock_kmalloc);
2692
2693/* Free an option memory block. Note, we actually want the inline
2694 * here as this allows gcc to detect the nullify and fold away the
2695 * condition entirely.
2696 */
2697static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2698				  const bool nullify)
2699{
2700	if (WARN_ON_ONCE(!mem))
2701		return;
2702	if (nullify)
2703		kfree_sensitive(mem);
2704	else
2705		kfree(mem);
2706	atomic_sub(size, &sk->sk_omem_alloc);
2707}
2708
2709void sock_kfree_s(struct sock *sk, void *mem, int size)
2710{
2711	__sock_kfree_s(sk, mem, size, false);
2712}
2713EXPORT_SYMBOL(sock_kfree_s);
2714
2715void sock_kzfree_s(struct sock *sk, void *mem, int size)
2716{
2717	__sock_kfree_s(sk, mem, size, true);
2718}
2719EXPORT_SYMBOL(sock_kzfree_s);
2720
2721/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2722   I think, these locks should be removed for datagram sockets.
2723 */
2724static long sock_wait_for_wmem(struct sock *sk, long timeo)
2725{
2726	DEFINE_WAIT(wait);
2727
2728	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2729	for (;;) {
2730		if (!timeo)
2731			break;
2732		if (signal_pending(current))
2733			break;
2734		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2735		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2736		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2737			break;
2738		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2739			break;
2740		if (READ_ONCE(sk->sk_err))
2741			break;
2742		timeo = schedule_timeout(timeo);
2743	}
2744	finish_wait(sk_sleep(sk), &wait);
2745	return timeo;
2746}
2747
2748
2749/*
2750 *	Generic send/receive buffer handlers
2751 */
2752
2753struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2754				     unsigned long data_len, int noblock,
2755				     int *errcode, int max_page_order)
2756{
2757	struct sk_buff *skb;
2758	long timeo;
2759	int err;
2760
2761	timeo = sock_sndtimeo(sk, noblock);
2762	for (;;) {
2763		err = sock_error(sk);
2764		if (err != 0)
2765			goto failure;
2766
2767		err = -EPIPE;
2768		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2769			goto failure;
2770
2771		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2772			break;
2773
2774		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2775		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2776		err = -EAGAIN;
2777		if (!timeo)
2778			goto failure;
2779		if (signal_pending(current))
2780			goto interrupted;
2781		timeo = sock_wait_for_wmem(sk, timeo);
2782	}
2783	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2784				   errcode, sk->sk_allocation);
2785	if (skb)
2786		skb_set_owner_w(skb, sk);
2787	return skb;
2788
2789interrupted:
2790	err = sock_intr_errno(timeo);
2791failure:
2792	*errcode = err;
2793	return NULL;
2794}
2795EXPORT_SYMBOL(sock_alloc_send_pskb);
2796
2797int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2798		     struct sockcm_cookie *sockc)
2799{
2800	u32 tsflags;
2801
2802	switch (cmsg->cmsg_type) {
2803	case SO_MARK:
2804		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2805		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2806			return -EPERM;
2807		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2808			return -EINVAL;
2809		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2810		break;
2811	case SO_TIMESTAMPING_OLD:
2812	case SO_TIMESTAMPING_NEW:
2813		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2814			return -EINVAL;
2815
2816		tsflags = *(u32 *)CMSG_DATA(cmsg);
2817		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2818			return -EINVAL;
2819
2820		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2821		sockc->tsflags |= tsflags;
2822		break;
2823	case SCM_TXTIME:
2824		if (!sock_flag(sk, SOCK_TXTIME))
2825			return -EINVAL;
2826		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2827			return -EINVAL;
2828		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2829		break;
2830	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2831	case SCM_RIGHTS:
2832	case SCM_CREDENTIALS:
2833		break;
2834	default:
2835		return -EINVAL;
2836	}
2837	return 0;
2838}
2839EXPORT_SYMBOL(__sock_cmsg_send);
2840
2841int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2842		   struct sockcm_cookie *sockc)
2843{
2844	struct cmsghdr *cmsg;
2845	int ret;
2846
2847	for_each_cmsghdr(cmsg, msg) {
2848		if (!CMSG_OK(msg, cmsg))
2849			return -EINVAL;
2850		if (cmsg->cmsg_level != SOL_SOCKET)
2851			continue;
2852		ret = __sock_cmsg_send(sk, cmsg, sockc);
2853		if (ret)
2854			return ret;
2855	}
2856	return 0;
2857}
2858EXPORT_SYMBOL(sock_cmsg_send);
2859
2860static void sk_enter_memory_pressure(struct sock *sk)
2861{
2862	if (!sk->sk_prot->enter_memory_pressure)
2863		return;
2864
2865	sk->sk_prot->enter_memory_pressure(sk);
2866}
2867
2868static void sk_leave_memory_pressure(struct sock *sk)
2869{
2870	if (sk->sk_prot->leave_memory_pressure) {
2871		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2872				     tcp_leave_memory_pressure, sk);
2873	} else {
2874		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2875
2876		if (memory_pressure && READ_ONCE(*memory_pressure))
2877			WRITE_ONCE(*memory_pressure, 0);
2878	}
2879}
2880
2881DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2882
2883/**
2884 * skb_page_frag_refill - check that a page_frag contains enough room
2885 * @sz: minimum size of the fragment we want to get
2886 * @pfrag: pointer to page_frag
2887 * @gfp: priority for memory allocation
2888 *
2889 * Note: While this allocator tries to use high order pages, there is
2890 * no guarantee that allocations succeed. Therefore, @sz MUST be
2891 * less or equal than PAGE_SIZE.
2892 */
2893bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2894{
2895	if (pfrag->page) {
2896		if (page_ref_count(pfrag->page) == 1) {
2897			pfrag->offset = 0;
2898			return true;
2899		}
2900		if (pfrag->offset + sz <= pfrag->size)
2901			return true;
2902		put_page(pfrag->page);
2903	}
2904
2905	pfrag->offset = 0;
2906	if (SKB_FRAG_PAGE_ORDER &&
2907	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2908		/* Avoid direct reclaim but allow kswapd to wake */
2909		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2910					  __GFP_COMP | __GFP_NOWARN |
2911					  __GFP_NORETRY,
2912					  SKB_FRAG_PAGE_ORDER);
2913		if (likely(pfrag->page)) {
2914			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2915			return true;
2916		}
2917	}
2918	pfrag->page = alloc_page(gfp);
2919	if (likely(pfrag->page)) {
2920		pfrag->size = PAGE_SIZE;
2921		return true;
2922	}
2923	return false;
2924}
2925EXPORT_SYMBOL(skb_page_frag_refill);
2926
2927bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2928{
2929	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2930		return true;
2931
2932	sk_enter_memory_pressure(sk);
2933	sk_stream_moderate_sndbuf(sk);
2934	return false;
2935}
2936EXPORT_SYMBOL(sk_page_frag_refill);
2937
2938void __lock_sock(struct sock *sk)
2939	__releases(&sk->sk_lock.slock)
2940	__acquires(&sk->sk_lock.slock)
2941{
2942	DEFINE_WAIT(wait);
2943
2944	for (;;) {
2945		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2946					TASK_UNINTERRUPTIBLE);
2947		spin_unlock_bh(&sk->sk_lock.slock);
2948		schedule();
2949		spin_lock_bh(&sk->sk_lock.slock);
2950		if (!sock_owned_by_user(sk))
2951			break;
2952	}
2953	finish_wait(&sk->sk_lock.wq, &wait);
2954}
2955
2956void __release_sock(struct sock *sk)
2957	__releases(&sk->sk_lock.slock)
2958	__acquires(&sk->sk_lock.slock)
2959{
2960	struct sk_buff *skb, *next;
2961
2962	while ((skb = sk->sk_backlog.head) != NULL) {
2963		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2964
2965		spin_unlock_bh(&sk->sk_lock.slock);
2966
2967		do {
2968			next = skb->next;
2969			prefetch(next);
2970			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2971			skb_mark_not_on_list(skb);
2972			sk_backlog_rcv(sk, skb);
2973
2974			cond_resched();
2975
2976			skb = next;
2977		} while (skb != NULL);
2978
2979		spin_lock_bh(&sk->sk_lock.slock);
2980	}
2981
2982	/*
2983	 * Doing the zeroing here guarantee we can not loop forever
2984	 * while a wild producer attempts to flood us.
2985	 */
2986	sk->sk_backlog.len = 0;
2987}
2988
2989void __sk_flush_backlog(struct sock *sk)
2990{
2991	spin_lock_bh(&sk->sk_lock.slock);
2992	__release_sock(sk);
2993
2994	if (sk->sk_prot->release_cb)
2995		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
2996				     tcp_release_cb, sk);
2997
2998	spin_unlock_bh(&sk->sk_lock.slock);
2999}
3000EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3001
3002/**
3003 * sk_wait_data - wait for data to arrive at sk_receive_queue
3004 * @sk:    sock to wait on
3005 * @timeo: for how long
3006 * @skb:   last skb seen on sk_receive_queue
3007 *
3008 * Now socket state including sk->sk_err is changed only under lock,
3009 * hence we may omit checks after joining wait queue.
3010 * We check receive queue before schedule() only as optimization;
3011 * it is very likely that release_sock() added new data.
3012 */
3013int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3014{
3015	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3016	int rc;
3017
3018	add_wait_queue(sk_sleep(sk), &wait);
3019	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3020	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3021	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3022	remove_wait_queue(sk_sleep(sk), &wait);
3023	return rc;
3024}
3025EXPORT_SYMBOL(sk_wait_data);
3026
3027/**
3028 *	__sk_mem_raise_allocated - increase memory_allocated
3029 *	@sk: socket
3030 *	@size: memory size to allocate
3031 *	@amt: pages to allocate
3032 *	@kind: allocation type
3033 *
3034 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3035 *
3036 *	Unlike the globally shared limits among the sockets under same protocol,
3037 *	consuming the budget of a memcg won't have direct effect on other ones.
3038 *	So be optimistic about memcg's tolerance, and leave the callers to decide
3039 *	whether or not to raise allocated through sk_under_memory_pressure() or
3040 *	its variants.
3041 */
3042int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3043{
3044	struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3045	struct proto *prot = sk->sk_prot;
3046	bool charged = false;
3047	long allocated;
3048
3049	sk_memory_allocated_add(sk, amt);
3050	allocated = sk_memory_allocated(sk);
3051
3052	if (memcg) {
3053		if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3054			goto suppress_allocation;
3055		charged = true;
3056	}
3057
3058	/* Under limit. */
3059	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3060		sk_leave_memory_pressure(sk);
3061		return 1;
3062	}
3063
3064	/* Under pressure. */
3065	if (allocated > sk_prot_mem_limits(sk, 1))
3066		sk_enter_memory_pressure(sk);
3067
3068	/* Over hard limit. */
3069	if (allocated > sk_prot_mem_limits(sk, 2))
3070		goto suppress_allocation;
3071
3072	/* Guarantee minimum buffer size under pressure (either global
3073	 * or memcg) to make sure features described in RFC 7323 (TCP
3074	 * Extensions for High Performance) work properly.
3075	 *
3076	 * This rule does NOT stand when exceeds global or memcg's hard
3077	 * limit, or else a DoS attack can be taken place by spawning
3078	 * lots of sockets whose usage are under minimum buffer size.
3079	 */
3080	if (kind == SK_MEM_RECV) {
3081		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3082			return 1;
3083
3084	} else { /* SK_MEM_SEND */
3085		int wmem0 = sk_get_wmem0(sk, prot);
3086
3087		if (sk->sk_type == SOCK_STREAM) {
3088			if (sk->sk_wmem_queued < wmem0)
3089				return 1;
3090		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3091				return 1;
3092		}
3093	}
3094
3095	if (sk_has_memory_pressure(sk)) {
3096		u64 alloc;
3097
3098		/* The following 'average' heuristic is within the
3099		 * scope of global accounting, so it only makes
3100		 * sense for global memory pressure.
3101		 */
3102		if (!sk_under_global_memory_pressure(sk))
3103			return 1;
3104
3105		/* Try to be fair among all the sockets under global
3106		 * pressure by allowing the ones that below average
3107		 * usage to raise.
3108		 */
3109		alloc = sk_sockets_allocated_read_positive(sk);
3110		if (sk_prot_mem_limits(sk, 2) > alloc *
3111		    sk_mem_pages(sk->sk_wmem_queued +
3112				 atomic_read(&sk->sk_rmem_alloc) +
3113				 sk->sk_forward_alloc))
3114			return 1;
3115	}
3116
3117suppress_allocation:
3118
3119	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3120		sk_stream_moderate_sndbuf(sk);
3121
3122		/* Fail only if socket is _under_ its sndbuf.
3123		 * In this case we cannot block, so that we have to fail.
3124		 */
3125		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3126			/* Force charge with __GFP_NOFAIL */
3127			if (memcg && !charged) {
3128				mem_cgroup_charge_skmem(memcg, amt,
3129					gfp_memcg_charge() | __GFP_NOFAIL);
3130			}
3131			return 1;
3132		}
3133	}
3134
3135	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3136		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3137
3138	sk_memory_allocated_sub(sk, amt);
3139
3140	if (charged)
3141		mem_cgroup_uncharge_skmem(memcg, amt);
3142
3143	return 0;
3144}
3145
3146/**
3147 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3148 *	@sk: socket
3149 *	@size: memory size to allocate
3150 *	@kind: allocation type
3151 *
3152 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3153 *	rmem allocation. This function assumes that protocols which have
3154 *	memory_pressure use sk_wmem_queued as write buffer accounting.
3155 */
3156int __sk_mem_schedule(struct sock *sk, int size, int kind)
3157{
3158	int ret, amt = sk_mem_pages(size);
3159
3160	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3161	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3162	if (!ret)
3163		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3164	return ret;
3165}
3166EXPORT_SYMBOL(__sk_mem_schedule);
3167
3168/**
3169 *	__sk_mem_reduce_allocated - reclaim memory_allocated
3170 *	@sk: socket
3171 *	@amount: number of quanta
3172 *
3173 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3174 */
3175void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3176{
3177	sk_memory_allocated_sub(sk, amount);
3178
3179	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3180		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3181
3182	if (sk_under_global_memory_pressure(sk) &&
3183	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3184		sk_leave_memory_pressure(sk);
3185}
3186
3187/**
3188 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3189 *	@sk: socket
3190 *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3191 */
3192void __sk_mem_reclaim(struct sock *sk, int amount)
3193{
3194	amount >>= PAGE_SHIFT;
3195	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3196	__sk_mem_reduce_allocated(sk, amount);
3197}
3198EXPORT_SYMBOL(__sk_mem_reclaim);
3199
3200int sk_set_peek_off(struct sock *sk, int val)
3201{
3202	WRITE_ONCE(sk->sk_peek_off, val);
3203	return 0;
3204}
3205EXPORT_SYMBOL_GPL(sk_set_peek_off);
3206
3207/*
3208 * Set of default routines for initialising struct proto_ops when
3209 * the protocol does not support a particular function. In certain
3210 * cases where it makes no sense for a protocol to have a "do nothing"
3211 * function, some default processing is provided.
3212 */
3213
3214int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3215{
3216	return -EOPNOTSUPP;
3217}
3218EXPORT_SYMBOL(sock_no_bind);
3219
3220int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3221		    int len, int flags)
3222{
3223	return -EOPNOTSUPP;
3224}
3225EXPORT_SYMBOL(sock_no_connect);
3226
3227int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3228{
3229	return -EOPNOTSUPP;
3230}
3231EXPORT_SYMBOL(sock_no_socketpair);
3232
3233int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3234		   bool kern)
3235{
3236	return -EOPNOTSUPP;
3237}
3238EXPORT_SYMBOL(sock_no_accept);
3239
3240int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3241		    int peer)
3242{
3243	return -EOPNOTSUPP;
3244}
3245EXPORT_SYMBOL(sock_no_getname);
3246
3247int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3248{
3249	return -EOPNOTSUPP;
3250}
3251EXPORT_SYMBOL(sock_no_ioctl);
3252
3253int sock_no_listen(struct socket *sock, int backlog)
3254{
3255	return -EOPNOTSUPP;
3256}
3257EXPORT_SYMBOL(sock_no_listen);
3258
3259int sock_no_shutdown(struct socket *sock, int how)
3260{
3261	return -EOPNOTSUPP;
3262}
3263EXPORT_SYMBOL(sock_no_shutdown);
3264
3265int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3266{
3267	return -EOPNOTSUPP;
3268}
3269EXPORT_SYMBOL(sock_no_sendmsg);
3270
3271int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3272{
3273	return -EOPNOTSUPP;
3274}
3275EXPORT_SYMBOL(sock_no_sendmsg_locked);
3276
3277int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3278		    int flags)
3279{
3280	return -EOPNOTSUPP;
3281}
3282EXPORT_SYMBOL(sock_no_recvmsg);
3283
3284int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3285{
3286	/* Mirror missing mmap method error code */
3287	return -ENODEV;
3288}
3289EXPORT_SYMBOL(sock_no_mmap);
3290
3291/*
3292 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3293 * various sock-based usage counts.
3294 */
3295void __receive_sock(struct file *file)
3296{
3297	struct socket *sock;
3298
3299	sock = sock_from_file(file);
3300	if (sock) {
3301		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3302		sock_update_classid(&sock->sk->sk_cgrp_data);
3303	}
3304}
3305
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3306/*
3307 *	Default Socket Callbacks
3308 */
3309
3310static void sock_def_wakeup(struct sock *sk)
3311{
3312	struct socket_wq *wq;
3313
3314	rcu_read_lock();
3315	wq = rcu_dereference(sk->sk_wq);
3316	if (skwq_has_sleeper(wq))
3317		wake_up_interruptible_all(&wq->wait);
3318	rcu_read_unlock();
3319}
3320
3321static void sock_def_error_report(struct sock *sk)
3322{
3323	struct socket_wq *wq;
3324
3325	rcu_read_lock();
3326	wq = rcu_dereference(sk->sk_wq);
3327	if (skwq_has_sleeper(wq))
3328		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3329	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3330	rcu_read_unlock();
3331}
3332
3333void sock_def_readable(struct sock *sk)
3334{
3335	struct socket_wq *wq;
3336
3337	trace_sk_data_ready(sk);
3338
3339	rcu_read_lock();
3340	wq = rcu_dereference(sk->sk_wq);
3341	if (skwq_has_sleeper(wq))
3342		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3343						EPOLLRDNORM | EPOLLRDBAND);
3344	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3345	rcu_read_unlock();
3346}
3347
3348static void sock_def_write_space(struct sock *sk)
3349{
3350	struct socket_wq *wq;
3351
3352	rcu_read_lock();
3353
3354	/* Do not wake up a writer until he can make "significant"
3355	 * progress.  --DaveM
3356	 */
3357	if (sock_writeable(sk)) {
3358		wq = rcu_dereference(sk->sk_wq);
3359		if (skwq_has_sleeper(wq))
3360			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3361						EPOLLWRNORM | EPOLLWRBAND);
3362
3363		/* Should agree with poll, otherwise some programs break */
3364		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3365	}
3366
3367	rcu_read_unlock();
3368}
3369
3370/* An optimised version of sock_def_write_space(), should only be called
3371 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3372 * ->sk_wmem_alloc.
3373 */
3374static void sock_def_write_space_wfree(struct sock *sk)
3375{
3376	/* Do not wake up a writer until he can make "significant"
3377	 * progress.  --DaveM
3378	 */
3379	if (sock_writeable(sk)) {
3380		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3381
3382		/* rely on refcount_sub from sock_wfree() */
3383		smp_mb__after_atomic();
3384		if (wq && waitqueue_active(&wq->wait))
3385			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3386						EPOLLWRNORM | EPOLLWRBAND);
3387
3388		/* Should agree with poll, otherwise some programs break */
3389		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3390	}
3391}
3392
3393static void sock_def_destruct(struct sock *sk)
3394{
3395}
3396
3397void sk_send_sigurg(struct sock *sk)
3398{
3399	if (sk->sk_socket && sk->sk_socket->file)
3400		if (send_sigurg(&sk->sk_socket->file->f_owner))
3401			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3402}
3403EXPORT_SYMBOL(sk_send_sigurg);
3404
3405void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3406		    unsigned long expires)
3407{
3408	if (!mod_timer(timer, expires))
3409		sock_hold(sk);
3410}
3411EXPORT_SYMBOL(sk_reset_timer);
3412
3413void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3414{
3415	if (del_timer(timer))
3416		__sock_put(sk);
3417}
3418EXPORT_SYMBOL(sk_stop_timer);
3419
3420void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3421{
3422	if (del_timer_sync(timer))
3423		__sock_put(sk);
3424}
3425EXPORT_SYMBOL(sk_stop_timer_sync);
3426
3427void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3428{
3429	sk_init_common(sk);
3430	sk->sk_send_head	=	NULL;
3431
3432	timer_setup(&sk->sk_timer, NULL, 0);
3433
3434	sk->sk_allocation	=	GFP_KERNEL;
3435	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3436	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3437	sk->sk_state		=	TCP_CLOSE;
3438	sk->sk_use_task_frag	=	true;
3439	sk_set_socket(sk, sock);
3440
3441	sock_set_flag(sk, SOCK_ZAPPED);
3442
3443	if (sock) {
3444		sk->sk_type	=	sock->type;
3445		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3446		sock->sk	=	sk;
 
3447	} else {
3448		RCU_INIT_POINTER(sk->sk_wq, NULL);
 
3449	}
3450	sk->sk_uid	=	uid;
3451
3452	rwlock_init(&sk->sk_callback_lock);
3453	if (sk->sk_kern_sock)
3454		lockdep_set_class_and_name(
3455			&sk->sk_callback_lock,
3456			af_kern_callback_keys + sk->sk_family,
3457			af_family_kern_clock_key_strings[sk->sk_family]);
3458	else
3459		lockdep_set_class_and_name(
3460			&sk->sk_callback_lock,
3461			af_callback_keys + sk->sk_family,
3462			af_family_clock_key_strings[sk->sk_family]);
3463
3464	sk->sk_state_change	=	sock_def_wakeup;
3465	sk->sk_data_ready	=	sock_def_readable;
3466	sk->sk_write_space	=	sock_def_write_space;
3467	sk->sk_error_report	=	sock_def_error_report;
3468	sk->sk_destruct		=	sock_def_destruct;
3469
3470	sk->sk_frag.page	=	NULL;
3471	sk->sk_frag.offset	=	0;
3472	sk->sk_peek_off		=	-1;
3473
3474	sk->sk_peer_pid 	=	NULL;
3475	sk->sk_peer_cred	=	NULL;
3476	spin_lock_init(&sk->sk_peer_lock);
3477
3478	sk->sk_write_pending	=	0;
3479	sk->sk_rcvlowat		=	1;
3480	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3481	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3482
3483	sk->sk_stamp = SK_DEFAULT_STAMP;
3484#if BITS_PER_LONG==32
3485	seqlock_init(&sk->sk_stamp_seq);
3486#endif
3487	atomic_set(&sk->sk_zckey, 0);
3488
3489#ifdef CONFIG_NET_RX_BUSY_POLL
3490	sk->sk_napi_id		=	0;
3491	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3492#endif
3493
3494	sk->sk_max_pacing_rate = ~0UL;
3495	sk->sk_pacing_rate = ~0UL;
3496	WRITE_ONCE(sk->sk_pacing_shift, 10);
3497	sk->sk_incoming_cpu = -1;
3498
3499	sk_rx_queue_clear(sk);
3500	/*
3501	 * Before updating sk_refcnt, we must commit prior changes to memory
3502	 * (Documentation/RCU/rculist_nulls.rst for details)
3503	 */
3504	smp_wmb();
3505	refcount_set(&sk->sk_refcnt, 1);
3506	atomic_set(&sk->sk_drops, 0);
3507}
3508EXPORT_SYMBOL(sock_init_data_uid);
3509
3510void sock_init_data(struct socket *sock, struct sock *sk)
3511{
3512	kuid_t uid = sock ?
3513		SOCK_INODE(sock)->i_uid :
3514		make_kuid(sock_net(sk)->user_ns, 0);
3515
3516	sock_init_data_uid(sock, sk, uid);
3517}
3518EXPORT_SYMBOL(sock_init_data);
3519
3520void lock_sock_nested(struct sock *sk, int subclass)
3521{
3522	/* The sk_lock has mutex_lock() semantics here. */
3523	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3524
3525	might_sleep();
3526	spin_lock_bh(&sk->sk_lock.slock);
3527	if (sock_owned_by_user_nocheck(sk))
3528		__lock_sock(sk);
3529	sk->sk_lock.owned = 1;
3530	spin_unlock_bh(&sk->sk_lock.slock);
3531}
3532EXPORT_SYMBOL(lock_sock_nested);
3533
3534void release_sock(struct sock *sk)
3535{
3536	spin_lock_bh(&sk->sk_lock.slock);
3537	if (sk->sk_backlog.tail)
3538		__release_sock(sk);
3539
 
 
 
3540	if (sk->sk_prot->release_cb)
3541		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3542				     tcp_release_cb, sk);
3543
3544	sock_release_ownership(sk);
3545	if (waitqueue_active(&sk->sk_lock.wq))
3546		wake_up(&sk->sk_lock.wq);
3547	spin_unlock_bh(&sk->sk_lock.slock);
3548}
3549EXPORT_SYMBOL(release_sock);
3550
3551bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3552{
3553	might_sleep();
3554	spin_lock_bh(&sk->sk_lock.slock);
3555
3556	if (!sock_owned_by_user_nocheck(sk)) {
3557		/*
3558		 * Fast path return with bottom halves disabled and
3559		 * sock::sk_lock.slock held.
3560		 *
3561		 * The 'mutex' is not contended and holding
3562		 * sock::sk_lock.slock prevents all other lockers to
3563		 * proceed so the corresponding unlock_sock_fast() can
3564		 * avoid the slow path of release_sock() completely and
3565		 * just release slock.
3566		 *
3567		 * From a semantical POV this is equivalent to 'acquiring'
3568		 * the 'mutex', hence the corresponding lockdep
3569		 * mutex_release() has to happen in the fast path of
3570		 * unlock_sock_fast().
3571		 */
3572		return false;
3573	}
3574
3575	__lock_sock(sk);
3576	sk->sk_lock.owned = 1;
3577	__acquire(&sk->sk_lock.slock);
3578	spin_unlock_bh(&sk->sk_lock.slock);
3579	return true;
3580}
3581EXPORT_SYMBOL(__lock_sock_fast);
3582
3583int sock_gettstamp(struct socket *sock, void __user *userstamp,
3584		   bool timeval, bool time32)
3585{
3586	struct sock *sk = sock->sk;
3587	struct timespec64 ts;
3588
3589	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3590	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3591	if (ts.tv_sec == -1)
3592		return -ENOENT;
3593	if (ts.tv_sec == 0) {
3594		ktime_t kt = ktime_get_real();
3595		sock_write_timestamp(sk, kt);
3596		ts = ktime_to_timespec64(kt);
3597	}
3598
3599	if (timeval)
3600		ts.tv_nsec /= 1000;
3601
3602#ifdef CONFIG_COMPAT_32BIT_TIME
3603	if (time32)
3604		return put_old_timespec32(&ts, userstamp);
3605#endif
3606#ifdef CONFIG_SPARC64
3607	/* beware of padding in sparc64 timeval */
3608	if (timeval && !in_compat_syscall()) {
3609		struct __kernel_old_timeval __user tv = {
3610			.tv_sec = ts.tv_sec,
3611			.tv_usec = ts.tv_nsec,
3612		};
3613		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3614			return -EFAULT;
3615		return 0;
3616	}
3617#endif
3618	return put_timespec64(&ts, userstamp);
3619}
3620EXPORT_SYMBOL(sock_gettstamp);
3621
3622void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3623{
3624	if (!sock_flag(sk, flag)) {
3625		unsigned long previous_flags = sk->sk_flags;
3626
3627		sock_set_flag(sk, flag);
3628		/*
3629		 * we just set one of the two flags which require net
3630		 * time stamping, but time stamping might have been on
3631		 * already because of the other one
3632		 */
3633		if (sock_needs_netstamp(sk) &&
3634		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3635			net_enable_timestamp();
3636	}
3637}
3638
3639int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3640		       int level, int type)
3641{
3642	struct sock_exterr_skb *serr;
3643	struct sk_buff *skb;
3644	int copied, err;
3645
3646	err = -EAGAIN;
3647	skb = sock_dequeue_err_skb(sk);
3648	if (skb == NULL)
3649		goto out;
3650
3651	copied = skb->len;
3652	if (copied > len) {
3653		msg->msg_flags |= MSG_TRUNC;
3654		copied = len;
3655	}
3656	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3657	if (err)
3658		goto out_free_skb;
3659
3660	sock_recv_timestamp(msg, sk, skb);
3661
3662	serr = SKB_EXT_ERR(skb);
3663	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3664
3665	msg->msg_flags |= MSG_ERRQUEUE;
3666	err = copied;
3667
3668out_free_skb:
3669	kfree_skb(skb);
3670out:
3671	return err;
3672}
3673EXPORT_SYMBOL(sock_recv_errqueue);
3674
3675/*
3676 *	Get a socket option on an socket.
3677 *
3678 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3679 *	asynchronous errors should be reported by getsockopt. We assume
3680 *	this means if you specify SO_ERROR (otherwise whats the point of it).
3681 */
3682int sock_common_getsockopt(struct socket *sock, int level, int optname,
3683			   char __user *optval, int __user *optlen)
3684{
3685	struct sock *sk = sock->sk;
3686
3687	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3688	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3689}
3690EXPORT_SYMBOL(sock_common_getsockopt);
3691
3692int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3693			int flags)
3694{
3695	struct sock *sk = sock->sk;
3696	int addr_len = 0;
3697	int err;
3698
3699	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3700	if (err >= 0)
3701		msg->msg_namelen = addr_len;
3702	return err;
3703}
3704EXPORT_SYMBOL(sock_common_recvmsg);
3705
3706/*
3707 *	Set socket options on an inet socket.
3708 */
3709int sock_common_setsockopt(struct socket *sock, int level, int optname,
3710			   sockptr_t optval, unsigned int optlen)
3711{
3712	struct sock *sk = sock->sk;
3713
3714	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3715	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3716}
3717EXPORT_SYMBOL(sock_common_setsockopt);
3718
3719void sk_common_release(struct sock *sk)
3720{
3721	if (sk->sk_prot->destroy)
3722		sk->sk_prot->destroy(sk);
3723
3724	/*
3725	 * Observation: when sk_common_release is called, processes have
3726	 * no access to socket. But net still has.
3727	 * Step one, detach it from networking:
3728	 *
3729	 * A. Remove from hash tables.
3730	 */
3731
3732	sk->sk_prot->unhash(sk);
3733
3734	/*
3735	 * In this point socket cannot receive new packets, but it is possible
3736	 * that some packets are in flight because some CPU runs receiver and
3737	 * did hash table lookup before we unhashed socket. They will achieve
3738	 * receive queue and will be purged by socket destructor.
3739	 *
3740	 * Also we still have packets pending on receive queue and probably,
3741	 * our own packets waiting in device queues. sock_destroy will drain
3742	 * receive queue, but transmitted packets will delay socket destruction
3743	 * until the last reference will be released.
3744	 */
3745
3746	sock_orphan(sk);
3747
3748	xfrm_sk_free_policy(sk);
3749
 
 
3750	sock_put(sk);
3751}
3752EXPORT_SYMBOL(sk_common_release);
3753
3754void sk_get_meminfo(const struct sock *sk, u32 *mem)
3755{
3756	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3757
3758	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3759	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3760	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3761	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3762	mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk);
3763	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3764	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3765	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3766	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3767}
3768
3769#ifdef CONFIG_PROC_FS
3770static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3771
3772int sock_prot_inuse_get(struct net *net, struct proto *prot)
3773{
3774	int cpu, idx = prot->inuse_idx;
3775	int res = 0;
3776
3777	for_each_possible_cpu(cpu)
3778		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3779
3780	return res >= 0 ? res : 0;
3781}
3782EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3783
3784int sock_inuse_get(struct net *net)
3785{
3786	int cpu, res = 0;
3787
3788	for_each_possible_cpu(cpu)
3789		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3790
3791	return res;
3792}
3793
3794EXPORT_SYMBOL_GPL(sock_inuse_get);
3795
3796static int __net_init sock_inuse_init_net(struct net *net)
3797{
3798	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3799	if (net->core.prot_inuse == NULL)
3800		return -ENOMEM;
3801	return 0;
3802}
3803
3804static void __net_exit sock_inuse_exit_net(struct net *net)
3805{
3806	free_percpu(net->core.prot_inuse);
3807}
3808
3809static struct pernet_operations net_inuse_ops = {
3810	.init = sock_inuse_init_net,
3811	.exit = sock_inuse_exit_net,
3812};
3813
3814static __init int net_inuse_init(void)
3815{
3816	if (register_pernet_subsys(&net_inuse_ops))
3817		panic("Cannot initialize net inuse counters");
3818
3819	return 0;
3820}
3821
3822core_initcall(net_inuse_init);
3823
3824static int assign_proto_idx(struct proto *prot)
3825{
3826	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3827
3828	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3829		pr_err("PROTO_INUSE_NR exhausted\n");
3830		return -ENOSPC;
3831	}
3832
3833	set_bit(prot->inuse_idx, proto_inuse_idx);
3834	return 0;
3835}
3836
3837static void release_proto_idx(struct proto *prot)
3838{
3839	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3840		clear_bit(prot->inuse_idx, proto_inuse_idx);
3841}
3842#else
3843static inline int assign_proto_idx(struct proto *prot)
3844{
3845	return 0;
3846}
3847
3848static inline void release_proto_idx(struct proto *prot)
3849{
3850}
3851
3852#endif
3853
3854static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3855{
3856	if (!twsk_prot)
3857		return;
3858	kfree(twsk_prot->twsk_slab_name);
3859	twsk_prot->twsk_slab_name = NULL;
3860	kmem_cache_destroy(twsk_prot->twsk_slab);
3861	twsk_prot->twsk_slab = NULL;
3862}
3863
3864static int tw_prot_init(const struct proto *prot)
3865{
3866	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3867
3868	if (!twsk_prot)
3869		return 0;
3870
3871	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3872					      prot->name);
3873	if (!twsk_prot->twsk_slab_name)
3874		return -ENOMEM;
3875
3876	twsk_prot->twsk_slab =
3877		kmem_cache_create(twsk_prot->twsk_slab_name,
3878				  twsk_prot->twsk_obj_size, 0,
3879				  SLAB_ACCOUNT | prot->slab_flags,
3880				  NULL);
3881	if (!twsk_prot->twsk_slab) {
3882		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3883			prot->name);
3884		return -ENOMEM;
3885	}
3886
3887	return 0;
3888}
3889
3890static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3891{
3892	if (!rsk_prot)
3893		return;
3894	kfree(rsk_prot->slab_name);
3895	rsk_prot->slab_name = NULL;
3896	kmem_cache_destroy(rsk_prot->slab);
3897	rsk_prot->slab = NULL;
3898}
3899
3900static int req_prot_init(const struct proto *prot)
3901{
3902	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3903
3904	if (!rsk_prot)
3905		return 0;
3906
3907	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3908					prot->name);
3909	if (!rsk_prot->slab_name)
3910		return -ENOMEM;
3911
3912	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3913					   rsk_prot->obj_size, 0,
3914					   SLAB_ACCOUNT | prot->slab_flags,
3915					   NULL);
3916
3917	if (!rsk_prot->slab) {
3918		pr_crit("%s: Can't create request sock SLAB cache!\n",
3919			prot->name);
3920		return -ENOMEM;
3921	}
3922	return 0;
3923}
3924
3925int proto_register(struct proto *prot, int alloc_slab)
3926{
3927	int ret = -ENOBUFS;
3928
3929	if (prot->memory_allocated && !prot->sysctl_mem) {
3930		pr_err("%s: missing sysctl_mem\n", prot->name);
3931		return -EINVAL;
3932	}
3933	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3934		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3935		return -EINVAL;
3936	}
3937	if (alloc_slab) {
3938		prot->slab = kmem_cache_create_usercopy(prot->name,
3939					prot->obj_size, 0,
3940					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3941					prot->slab_flags,
3942					prot->useroffset, prot->usersize,
3943					NULL);
3944
3945		if (prot->slab == NULL) {
3946			pr_crit("%s: Can't create sock SLAB cache!\n",
3947				prot->name);
3948			goto out;
3949		}
3950
3951		if (req_prot_init(prot))
3952			goto out_free_request_sock_slab;
3953
3954		if (tw_prot_init(prot))
3955			goto out_free_timewait_sock_slab;
3956	}
3957
3958	mutex_lock(&proto_list_mutex);
3959	ret = assign_proto_idx(prot);
3960	if (ret) {
3961		mutex_unlock(&proto_list_mutex);
3962		goto out_free_timewait_sock_slab;
3963	}
3964	list_add(&prot->node, &proto_list);
3965	mutex_unlock(&proto_list_mutex);
3966	return ret;
3967
3968out_free_timewait_sock_slab:
3969	if (alloc_slab)
3970		tw_prot_cleanup(prot->twsk_prot);
3971out_free_request_sock_slab:
3972	if (alloc_slab) {
3973		req_prot_cleanup(prot->rsk_prot);
3974
3975		kmem_cache_destroy(prot->slab);
3976		prot->slab = NULL;
3977	}
3978out:
3979	return ret;
3980}
3981EXPORT_SYMBOL(proto_register);
3982
3983void proto_unregister(struct proto *prot)
3984{
3985	mutex_lock(&proto_list_mutex);
3986	release_proto_idx(prot);
3987	list_del(&prot->node);
3988	mutex_unlock(&proto_list_mutex);
3989
3990	kmem_cache_destroy(prot->slab);
3991	prot->slab = NULL;
3992
3993	req_prot_cleanup(prot->rsk_prot);
3994	tw_prot_cleanup(prot->twsk_prot);
3995}
3996EXPORT_SYMBOL(proto_unregister);
3997
3998int sock_load_diag_module(int family, int protocol)
3999{
4000	if (!protocol) {
4001		if (!sock_is_registered(family))
4002			return -ENOENT;
4003
4004		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4005				      NETLINK_SOCK_DIAG, family);
4006	}
4007
4008#ifdef CONFIG_INET
4009	if (family == AF_INET &&
4010	    protocol != IPPROTO_RAW &&
4011	    protocol < MAX_INET_PROTOS &&
4012	    !rcu_access_pointer(inet_protos[protocol]))
4013		return -ENOENT;
4014#endif
4015
4016	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4017			      NETLINK_SOCK_DIAG, family, protocol);
4018}
4019EXPORT_SYMBOL(sock_load_diag_module);
4020
4021#ifdef CONFIG_PROC_FS
4022static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4023	__acquires(proto_list_mutex)
4024{
4025	mutex_lock(&proto_list_mutex);
4026	return seq_list_start_head(&proto_list, *pos);
4027}
4028
4029static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4030{
4031	return seq_list_next(v, &proto_list, pos);
4032}
4033
4034static void proto_seq_stop(struct seq_file *seq, void *v)
4035	__releases(proto_list_mutex)
4036{
4037	mutex_unlock(&proto_list_mutex);
4038}
4039
4040static char proto_method_implemented(const void *method)
4041{
4042	return method == NULL ? 'n' : 'y';
4043}
4044static long sock_prot_memory_allocated(struct proto *proto)
4045{
4046	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4047}
4048
4049static const char *sock_prot_memory_pressure(struct proto *proto)
4050{
4051	return proto->memory_pressure != NULL ?
4052	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4053}
4054
4055static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4056{
4057
4058	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4059			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4060		   proto->name,
4061		   proto->obj_size,
4062		   sock_prot_inuse_get(seq_file_net(seq), proto),
4063		   sock_prot_memory_allocated(proto),
4064		   sock_prot_memory_pressure(proto),
4065		   proto->max_header,
4066		   proto->slab == NULL ? "no" : "yes",
4067		   module_name(proto->owner),
4068		   proto_method_implemented(proto->close),
4069		   proto_method_implemented(proto->connect),
4070		   proto_method_implemented(proto->disconnect),
4071		   proto_method_implemented(proto->accept),
4072		   proto_method_implemented(proto->ioctl),
4073		   proto_method_implemented(proto->init),
4074		   proto_method_implemented(proto->destroy),
4075		   proto_method_implemented(proto->shutdown),
4076		   proto_method_implemented(proto->setsockopt),
4077		   proto_method_implemented(proto->getsockopt),
4078		   proto_method_implemented(proto->sendmsg),
4079		   proto_method_implemented(proto->recvmsg),
 
4080		   proto_method_implemented(proto->bind),
4081		   proto_method_implemented(proto->backlog_rcv),
4082		   proto_method_implemented(proto->hash),
4083		   proto_method_implemented(proto->unhash),
4084		   proto_method_implemented(proto->get_port),
4085		   proto_method_implemented(proto->enter_memory_pressure));
4086}
4087
4088static int proto_seq_show(struct seq_file *seq, void *v)
4089{
4090	if (v == &proto_list)
4091		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4092			   "protocol",
4093			   "size",
4094			   "sockets",
4095			   "memory",
4096			   "press",
4097			   "maxhdr",
4098			   "slab",
4099			   "module",
4100			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4101	else
4102		proto_seq_printf(seq, list_entry(v, struct proto, node));
4103	return 0;
4104}
4105
4106static const struct seq_operations proto_seq_ops = {
4107	.start  = proto_seq_start,
4108	.next   = proto_seq_next,
4109	.stop   = proto_seq_stop,
4110	.show   = proto_seq_show,
4111};
4112
4113static __net_init int proto_init_net(struct net *net)
4114{
4115	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4116			sizeof(struct seq_net_private)))
4117		return -ENOMEM;
4118
4119	return 0;
4120}
4121
4122static __net_exit void proto_exit_net(struct net *net)
4123{
4124	remove_proc_entry("protocols", net->proc_net);
4125}
4126
4127
4128static __net_initdata struct pernet_operations proto_net_ops = {
4129	.init = proto_init_net,
4130	.exit = proto_exit_net,
4131};
4132
4133static int __init proto_init(void)
4134{
4135	return register_pernet_subsys(&proto_net_ops);
4136}
4137
4138subsys_initcall(proto_init);
4139
4140#endif /* PROC_FS */
4141
4142#ifdef CONFIG_NET_RX_BUSY_POLL
4143bool sk_busy_loop_end(void *p, unsigned long start_time)
4144{
4145	struct sock *sk = p;
4146
4147	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4148		return true;
4149
4150	if (sk_is_udp(sk) &&
4151	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4152		return true;
4153
4154	return sk_busy_loop_timeout(sk, start_time);
4155}
4156EXPORT_SYMBOL(sk_busy_loop_end);
4157#endif /* CONFIG_NET_RX_BUSY_POLL */
4158
4159int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4160{
4161	if (!sk->sk_prot->bind_add)
4162		return -EOPNOTSUPP;
4163	return sk->sk_prot->bind_add(sk, addr, addr_len);
4164}
4165EXPORT_SYMBOL(sock_bind_add);
4166
4167/* Copy 'size' bytes from userspace and return `size` back to userspace */
4168int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4169		     void __user *arg, void *karg, size_t size)
4170{
4171	int ret;
4172
4173	if (copy_from_user(karg, arg, size))
4174		return -EFAULT;
4175
4176	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4177	if (ret)
4178		return ret;
4179
4180	if (copy_to_user(arg, karg, size))
4181		return -EFAULT;
4182
4183	return 0;
4184}
4185EXPORT_SYMBOL(sock_ioctl_inout);
4186
4187/* This is the most common ioctl prep function, where the result (4 bytes) is
4188 * copied back to userspace if the ioctl() returns successfully. No input is
4189 * copied from userspace as input argument.
4190 */
4191static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4192{
4193	int ret, karg = 0;
4194
4195	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4196	if (ret)
4197		return ret;
4198
4199	return put_user(karg, (int __user *)arg);
4200}
4201
4202/* A wrapper around sock ioctls, which copies the data from userspace
4203 * (depending on the protocol/ioctl), and copies back the result to userspace.
4204 * The main motivation for this function is to pass kernel memory to the
4205 * protocol ioctl callbacks, instead of userspace memory.
4206 */
4207int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4208{
4209	int rc = 1;
4210
4211	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4212		rc = ipmr_sk_ioctl(sk, cmd, arg);
4213	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4214		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4215	else if (sk_is_phonet(sk))
4216		rc = phonet_sk_ioctl(sk, cmd, arg);
4217
4218	/* If ioctl was processed, returns its value */
4219	if (rc <= 0)
4220		return rc;
4221
4222	/* Otherwise call the default handler */
4223	return sock_ioctl_out(sk, cmd, arg);
4224}
4225EXPORT_SYMBOL(sk_ioctl);
v6.2
   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 *		Generic socket support routines. Memory allocators, socket lock/release
   8 *		handler for protocols to use and generic option handler.
   9 *
  10 * Authors:	Ross Biro
  11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *		Florian La Roche, <flla@stud.uni-sb.de>
  13 *		Alan Cox, <A.Cox@swansea.ac.uk>
  14 *
  15 * Fixes:
  16 *		Alan Cox	: 	Numerous verify_area() problems
  17 *		Alan Cox	:	Connecting on a connecting socket
  18 *					now returns an error for tcp.
  19 *		Alan Cox	:	sock->protocol is set correctly.
  20 *					and is not sometimes left as 0.
  21 *		Alan Cox	:	connect handles icmp errors on a
  22 *					connect properly. Unfortunately there
  23 *					is a restart syscall nasty there. I
  24 *					can't match BSD without hacking the C
  25 *					library. Ideas urgently sought!
  26 *		Alan Cox	:	Disallow bind() to addresses that are
  27 *					not ours - especially broadcast ones!!
  28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
  29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
  30 *					instead they leave that for the DESTROY timer.
  31 *		Alan Cox	:	Clean up error flag in accept
  32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
  33 *					was buggy. Put a remove_sock() in the handler
  34 *					for memory when we hit 0. Also altered the timer
  35 *					code. The ACK stuff can wait and needs major
  36 *					TCP layer surgery.
  37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
  38 *					and fixed timer/inet_bh race.
  39 *		Alan Cox	:	Added zapped flag for TCP
  40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
  41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
  42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
  43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
  44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
  45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
  46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
  47 *	Pauline Middelink	:	identd support
  48 *		Alan Cox	:	Fixed connect() taking signals I think.
  49 *		Alan Cox	:	SO_LINGER supported
  50 *		Alan Cox	:	Error reporting fixes
  51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
  52 *		Alan Cox	:	inet sockets don't set sk->type!
  53 *		Alan Cox	:	Split socket option code
  54 *		Alan Cox	:	Callbacks
  55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
  56 *		Alex		:	Removed restriction on inet fioctl
  57 *		Alan Cox	:	Splitting INET from NET core
  58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
  59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
  60 *		Alan Cox	:	Split IP from generic code
  61 *		Alan Cox	:	New kfree_skbmem()
  62 *		Alan Cox	:	Make SO_DEBUG superuser only.
  63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
  64 *					(compatibility fix)
  65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
  66 *		Alan Cox	:	Allocator for a socket is settable.
  67 *		Alan Cox	:	SO_ERROR includes soft errors.
  68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
  69 *		Alan Cox	: 	Generic socket allocation to make hooks
  70 *					easier (suggested by Craig Metz).
  71 *		Michael Pall	:	SO_ERROR returns positive errno again
  72 *              Steve Whitehouse:       Added default destructor to free
  73 *                                      protocol private data.
  74 *              Steve Whitehouse:       Added various other default routines
  75 *                                      common to several socket families.
  76 *              Chris Evans     :       Call suser() check last on F_SETOWN
  77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
  78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
  79 *		Andi Kleen	:	Fix write_space callback
  80 *		Chris Evans	:	Security fixes - signedness again
  81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
  82 *
  83 * To Fix:
  84 */
  85
  86#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  87
  88#include <asm/unaligned.h>
  89#include <linux/capability.h>
  90#include <linux/errno.h>
  91#include <linux/errqueue.h>
  92#include <linux/types.h>
  93#include <linux/socket.h>
  94#include <linux/in.h>
  95#include <linux/kernel.h>
  96#include <linux/module.h>
  97#include <linux/proc_fs.h>
  98#include <linux/seq_file.h>
  99#include <linux/sched.h>
 100#include <linux/sched/mm.h>
 101#include <linux/timer.h>
 102#include <linux/string.h>
 103#include <linux/sockios.h>
 104#include <linux/net.h>
 105#include <linux/mm.h>
 106#include <linux/slab.h>
 107#include <linux/interrupt.h>
 108#include <linux/poll.h>
 109#include <linux/tcp.h>
 
 110#include <linux/init.h>
 111#include <linux/highmem.h>
 112#include <linux/user_namespace.h>
 113#include <linux/static_key.h>
 114#include <linux/memcontrol.h>
 115#include <linux/prefetch.h>
 116#include <linux/compat.h>
 
 
 
 117
 118#include <linux/uaccess.h>
 119
 120#include <linux/netdevice.h>
 121#include <net/protocol.h>
 122#include <linux/skbuff.h>
 123#include <net/net_namespace.h>
 124#include <net/request_sock.h>
 125#include <net/sock.h>
 126#include <linux/net_tstamp.h>
 127#include <net/xfrm.h>
 128#include <linux/ipsec.h>
 129#include <net/cls_cgroup.h>
 130#include <net/netprio_cgroup.h>
 131#include <linux/sock_diag.h>
 132
 133#include <linux/filter.h>
 134#include <net/sock_reuseport.h>
 135#include <net/bpf_sk_storage.h>
 136
 137#include <trace/events/sock.h>
 138
 139#include <net/tcp.h>
 140#include <net/busy_poll.h>
 
 141
 142#include <linux/ethtool.h>
 143
 144#include "dev.h"
 145
 146static DEFINE_MUTEX(proto_list_mutex);
 147static LIST_HEAD(proto_list);
 148
 149static void sock_def_write_space_wfree(struct sock *sk);
 150static void sock_def_write_space(struct sock *sk);
 151
 152/**
 153 * sk_ns_capable - General socket capability test
 154 * @sk: Socket to use a capability on or through
 155 * @user_ns: The user namespace of the capability to use
 156 * @cap: The capability to use
 157 *
 158 * Test to see if the opener of the socket had when the socket was
 159 * created and the current process has the capability @cap in the user
 160 * namespace @user_ns.
 161 */
 162bool sk_ns_capable(const struct sock *sk,
 163		   struct user_namespace *user_ns, int cap)
 164{
 165	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
 166		ns_capable(user_ns, cap);
 167}
 168EXPORT_SYMBOL(sk_ns_capable);
 169
 170/**
 171 * sk_capable - Socket global capability test
 172 * @sk: Socket to use a capability on or through
 173 * @cap: The global capability to use
 174 *
 175 * Test to see if the opener of the socket had when the socket was
 176 * created and the current process has the capability @cap in all user
 177 * namespaces.
 178 */
 179bool sk_capable(const struct sock *sk, int cap)
 180{
 181	return sk_ns_capable(sk, &init_user_ns, cap);
 182}
 183EXPORT_SYMBOL(sk_capable);
 184
 185/**
 186 * sk_net_capable - Network namespace socket capability test
 187 * @sk: Socket to use a capability on or through
 188 * @cap: The capability to use
 189 *
 190 * Test to see if the opener of the socket had when the socket was created
 191 * and the current process has the capability @cap over the network namespace
 192 * the socket is a member of.
 193 */
 194bool sk_net_capable(const struct sock *sk, int cap)
 195{
 196	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
 197}
 198EXPORT_SYMBOL(sk_net_capable);
 199
 200/*
 201 * Each address family might have different locking rules, so we have
 202 * one slock key per address family and separate keys for internal and
 203 * userspace sockets.
 204 */
 205static struct lock_class_key af_family_keys[AF_MAX];
 206static struct lock_class_key af_family_kern_keys[AF_MAX];
 207static struct lock_class_key af_family_slock_keys[AF_MAX];
 208static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
 209
 210/*
 211 * Make lock validator output more readable. (we pre-construct these
 212 * strings build-time, so that runtime initialization of socket
 213 * locks is fast):
 214 */
 215
 216#define _sock_locks(x)						  \
 217  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
 218  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
 219  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
 220  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
 221  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
 222  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
 223  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
 224  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
 225  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
 226  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
 227  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
 228  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
 229  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
 230  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
 231  x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
 232  x "AF_MCTP"  , \
 233  x "AF_MAX"
 234
 235static const char *const af_family_key_strings[AF_MAX+1] = {
 236	_sock_locks("sk_lock-")
 237};
 238static const char *const af_family_slock_key_strings[AF_MAX+1] = {
 239	_sock_locks("slock-")
 240};
 241static const char *const af_family_clock_key_strings[AF_MAX+1] = {
 242	_sock_locks("clock-")
 243};
 244
 245static const char *const af_family_kern_key_strings[AF_MAX+1] = {
 246	_sock_locks("k-sk_lock-")
 247};
 248static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
 249	_sock_locks("k-slock-")
 250};
 251static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
 252	_sock_locks("k-clock-")
 253};
 254static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
 255	_sock_locks("rlock-")
 256};
 257static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
 258	_sock_locks("wlock-")
 259};
 260static const char *const af_family_elock_key_strings[AF_MAX+1] = {
 261	_sock_locks("elock-")
 262};
 263
 264/*
 265 * sk_callback_lock and sk queues locking rules are per-address-family,
 266 * so split the lock classes by using a per-AF key:
 267 */
 268static struct lock_class_key af_callback_keys[AF_MAX];
 269static struct lock_class_key af_rlock_keys[AF_MAX];
 270static struct lock_class_key af_wlock_keys[AF_MAX];
 271static struct lock_class_key af_elock_keys[AF_MAX];
 272static struct lock_class_key af_kern_callback_keys[AF_MAX];
 273
 274/* Run time adjustable parameters. */
 275__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 276EXPORT_SYMBOL(sysctl_wmem_max);
 277__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 278EXPORT_SYMBOL(sysctl_rmem_max);
 279__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 280__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 281
 282/* Maximal space eaten by iovec or ancillary data plus some space */
 283int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
 284EXPORT_SYMBOL(sysctl_optmem_max);
 285
 286int sysctl_tstamp_allow_data __read_mostly = 1;
 287
 288DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
 289EXPORT_SYMBOL_GPL(memalloc_socks_key);
 290
 291/**
 292 * sk_set_memalloc - sets %SOCK_MEMALLOC
 293 * @sk: socket to set it on
 294 *
 295 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 296 * It's the responsibility of the admin to adjust min_free_kbytes
 297 * to meet the requirements
 298 */
 299void sk_set_memalloc(struct sock *sk)
 300{
 301	sock_set_flag(sk, SOCK_MEMALLOC);
 302	sk->sk_allocation |= __GFP_MEMALLOC;
 303	static_branch_inc(&memalloc_socks_key);
 304}
 305EXPORT_SYMBOL_GPL(sk_set_memalloc);
 306
 307void sk_clear_memalloc(struct sock *sk)
 308{
 309	sock_reset_flag(sk, SOCK_MEMALLOC);
 310	sk->sk_allocation &= ~__GFP_MEMALLOC;
 311	static_branch_dec(&memalloc_socks_key);
 312
 313	/*
 314	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 315	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 316	 * it has rmem allocations due to the last swapfile being deactivated
 317	 * but there is a risk that the socket is unusable due to exceeding
 318	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 319	 */
 320	sk_mem_reclaim(sk);
 321}
 322EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 323
 324int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 325{
 326	int ret;
 327	unsigned int noreclaim_flag;
 328
 329	/* these should have been dropped before queueing */
 330	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 331
 332	noreclaim_flag = memalloc_noreclaim_save();
 333	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
 334				 tcp_v6_do_rcv,
 335				 tcp_v4_do_rcv,
 336				 sk, skb);
 337	memalloc_noreclaim_restore(noreclaim_flag);
 338
 339	return ret;
 340}
 341EXPORT_SYMBOL(__sk_backlog_rcv);
 342
 343void sk_error_report(struct sock *sk)
 344{
 345	sk->sk_error_report(sk);
 346
 347	switch (sk->sk_family) {
 348	case AF_INET:
 349		fallthrough;
 350	case AF_INET6:
 351		trace_inet_sk_error_report(sk);
 352		break;
 353	default:
 354		break;
 355	}
 356}
 357EXPORT_SYMBOL(sk_error_report);
 358
 359int sock_get_timeout(long timeo, void *optval, bool old_timeval)
 360{
 361	struct __kernel_sock_timeval tv;
 362
 363	if (timeo == MAX_SCHEDULE_TIMEOUT) {
 364		tv.tv_sec = 0;
 365		tv.tv_usec = 0;
 366	} else {
 367		tv.tv_sec = timeo / HZ;
 368		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
 369	}
 370
 371	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 372		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
 373		*(struct old_timeval32 *)optval = tv32;
 374		return sizeof(tv32);
 375	}
 376
 377	if (old_timeval) {
 378		struct __kernel_old_timeval old_tv;
 379		old_tv.tv_sec = tv.tv_sec;
 380		old_tv.tv_usec = tv.tv_usec;
 381		*(struct __kernel_old_timeval *)optval = old_tv;
 382		return sizeof(old_tv);
 383	}
 384
 385	*(struct __kernel_sock_timeval *)optval = tv;
 386	return sizeof(tv);
 387}
 388EXPORT_SYMBOL(sock_get_timeout);
 389
 390int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
 391			   sockptr_t optval, int optlen, bool old_timeval)
 392{
 393	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 394		struct old_timeval32 tv32;
 395
 396		if (optlen < sizeof(tv32))
 397			return -EINVAL;
 398
 399		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
 400			return -EFAULT;
 401		tv->tv_sec = tv32.tv_sec;
 402		tv->tv_usec = tv32.tv_usec;
 403	} else if (old_timeval) {
 404		struct __kernel_old_timeval old_tv;
 405
 406		if (optlen < sizeof(old_tv))
 407			return -EINVAL;
 408		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
 409			return -EFAULT;
 410		tv->tv_sec = old_tv.tv_sec;
 411		tv->tv_usec = old_tv.tv_usec;
 412	} else {
 413		if (optlen < sizeof(*tv))
 414			return -EINVAL;
 415		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
 416			return -EFAULT;
 417	}
 418
 419	return 0;
 420}
 421EXPORT_SYMBOL(sock_copy_user_timeval);
 422
 423static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
 424			    bool old_timeval)
 425{
 426	struct __kernel_sock_timeval tv;
 427	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
 
 428
 429	if (err)
 430		return err;
 431
 432	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 433		return -EDOM;
 434
 435	if (tv.tv_sec < 0) {
 436		static int warned __read_mostly;
 437
 438		*timeo_p = 0;
 439		if (warned < 10 && net_ratelimit()) {
 440			warned++;
 441			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 442				__func__, current->comm, task_pid_nr(current));
 443		}
 444		return 0;
 445	}
 446	*timeo_p = MAX_SCHEDULE_TIMEOUT;
 447	if (tv.tv_sec == 0 && tv.tv_usec == 0)
 448		return 0;
 449	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
 450		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
 
 451	return 0;
 452}
 453
 454static bool sock_needs_netstamp(const struct sock *sk)
 455{
 456	switch (sk->sk_family) {
 457	case AF_UNSPEC:
 458	case AF_UNIX:
 459		return false;
 460	default:
 461		return true;
 462	}
 463}
 464
 465static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 466{
 467	if (sk->sk_flags & flags) {
 468		sk->sk_flags &= ~flags;
 469		if (sock_needs_netstamp(sk) &&
 470		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 471			net_disable_timestamp();
 472	}
 473}
 474
 475
 476int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 477{
 478	unsigned long flags;
 479	struct sk_buff_head *list = &sk->sk_receive_queue;
 480
 481	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
 482		atomic_inc(&sk->sk_drops);
 483		trace_sock_rcvqueue_full(sk, skb);
 484		return -ENOMEM;
 485	}
 486
 487	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 488		atomic_inc(&sk->sk_drops);
 489		return -ENOBUFS;
 490	}
 491
 492	skb->dev = NULL;
 493	skb_set_owner_r(skb, sk);
 494
 495	/* we escape from rcu protected region, make sure we dont leak
 496	 * a norefcounted dst
 497	 */
 498	skb_dst_force(skb);
 499
 500	spin_lock_irqsave(&list->lock, flags);
 501	sock_skb_set_dropcount(sk, skb);
 502	__skb_queue_tail(list, skb);
 503	spin_unlock_irqrestore(&list->lock, flags);
 504
 505	if (!sock_flag(sk, SOCK_DEAD))
 506		sk->sk_data_ready(sk);
 507	return 0;
 508}
 509EXPORT_SYMBOL(__sock_queue_rcv_skb);
 510
 511int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
 512			      enum skb_drop_reason *reason)
 513{
 514	enum skb_drop_reason drop_reason;
 515	int err;
 516
 517	err = sk_filter(sk, skb);
 518	if (err) {
 519		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
 520		goto out;
 521	}
 522	err = __sock_queue_rcv_skb(sk, skb);
 523	switch (err) {
 524	case -ENOMEM:
 525		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
 526		break;
 527	case -ENOBUFS:
 528		drop_reason = SKB_DROP_REASON_PROTO_MEM;
 529		break;
 530	default:
 531		drop_reason = SKB_NOT_DROPPED_YET;
 532		break;
 533	}
 534out:
 535	if (reason)
 536		*reason = drop_reason;
 537	return err;
 538}
 539EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
 540
 541int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
 542		     const int nested, unsigned int trim_cap, bool refcounted)
 543{
 544	int rc = NET_RX_SUCCESS;
 545
 546	if (sk_filter_trim_cap(sk, skb, trim_cap))
 547		goto discard_and_relse;
 548
 549	skb->dev = NULL;
 550
 551	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 552		atomic_inc(&sk->sk_drops);
 553		goto discard_and_relse;
 554	}
 555	if (nested)
 556		bh_lock_sock_nested(sk);
 557	else
 558		bh_lock_sock(sk);
 559	if (!sock_owned_by_user(sk)) {
 560		/*
 561		 * trylock + unlock semantics:
 562		 */
 563		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 564
 565		rc = sk_backlog_rcv(sk, skb);
 566
 567		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
 568	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
 569		bh_unlock_sock(sk);
 570		atomic_inc(&sk->sk_drops);
 571		goto discard_and_relse;
 572	}
 573
 574	bh_unlock_sock(sk);
 575out:
 576	if (refcounted)
 577		sock_put(sk);
 578	return rc;
 579discard_and_relse:
 580	kfree_skb(skb);
 581	goto out;
 582}
 583EXPORT_SYMBOL(__sk_receive_skb);
 584
 585INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
 586							  u32));
 587INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
 588							   u32));
 589struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 590{
 591	struct dst_entry *dst = __sk_dst_get(sk);
 592
 593	if (dst && dst->obsolete &&
 594	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 595			       dst, cookie) == NULL) {
 596		sk_tx_queue_clear(sk);
 597		sk->sk_dst_pending_confirm = 0;
 598		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 599		dst_release(dst);
 600		return NULL;
 601	}
 602
 603	return dst;
 604}
 605EXPORT_SYMBOL(__sk_dst_check);
 606
 607struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 608{
 609	struct dst_entry *dst = sk_dst_get(sk);
 610
 611	if (dst && dst->obsolete &&
 612	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 613			       dst, cookie) == NULL) {
 614		sk_dst_reset(sk);
 615		dst_release(dst);
 616		return NULL;
 617	}
 618
 619	return dst;
 620}
 621EXPORT_SYMBOL(sk_dst_check);
 622
 623static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
 624{
 625	int ret = -ENOPROTOOPT;
 626#ifdef CONFIG_NETDEVICES
 627	struct net *net = sock_net(sk);
 628
 629	/* Sorry... */
 630	ret = -EPERM;
 631	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
 632		goto out;
 633
 634	ret = -EINVAL;
 635	if (ifindex < 0)
 636		goto out;
 637
 638	/* Paired with all READ_ONCE() done locklessly. */
 639	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
 640
 641	if (sk->sk_prot->rehash)
 642		sk->sk_prot->rehash(sk);
 643	sk_dst_reset(sk);
 644
 645	ret = 0;
 646
 647out:
 648#endif
 649
 650	return ret;
 651}
 652
 653int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
 654{
 655	int ret;
 656
 657	if (lock_sk)
 658		lock_sock(sk);
 659	ret = sock_bindtoindex_locked(sk, ifindex);
 660	if (lock_sk)
 661		release_sock(sk);
 662
 663	return ret;
 664}
 665EXPORT_SYMBOL(sock_bindtoindex);
 666
 667static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
 668{
 669	int ret = -ENOPROTOOPT;
 670#ifdef CONFIG_NETDEVICES
 671	struct net *net = sock_net(sk);
 672	char devname[IFNAMSIZ];
 673	int index;
 674
 675	ret = -EINVAL;
 676	if (optlen < 0)
 677		goto out;
 678
 679	/* Bind this socket to a particular device like "eth0",
 680	 * as specified in the passed interface name. If the
 681	 * name is "" or the option length is zero the socket
 682	 * is not bound.
 683	 */
 684	if (optlen > IFNAMSIZ - 1)
 685		optlen = IFNAMSIZ - 1;
 686	memset(devname, 0, sizeof(devname));
 687
 688	ret = -EFAULT;
 689	if (copy_from_sockptr(devname, optval, optlen))
 690		goto out;
 691
 692	index = 0;
 693	if (devname[0] != '\0') {
 694		struct net_device *dev;
 695
 696		rcu_read_lock();
 697		dev = dev_get_by_name_rcu(net, devname);
 698		if (dev)
 699			index = dev->ifindex;
 700		rcu_read_unlock();
 701		ret = -ENODEV;
 702		if (!dev)
 703			goto out;
 704	}
 705
 706	sockopt_lock_sock(sk);
 707	ret = sock_bindtoindex_locked(sk, index);
 708	sockopt_release_sock(sk);
 709out:
 710#endif
 711
 712	return ret;
 713}
 714
 715static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
 716				sockptr_t optlen, int len)
 717{
 718	int ret = -ENOPROTOOPT;
 719#ifdef CONFIG_NETDEVICES
 720	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 721	struct net *net = sock_net(sk);
 722	char devname[IFNAMSIZ];
 723
 724	if (bound_dev_if == 0) {
 725		len = 0;
 726		goto zero;
 727	}
 728
 729	ret = -EINVAL;
 730	if (len < IFNAMSIZ)
 731		goto out;
 732
 733	ret = netdev_get_name(net, devname, bound_dev_if);
 734	if (ret)
 735		goto out;
 736
 737	len = strlen(devname) + 1;
 738
 739	ret = -EFAULT;
 740	if (copy_to_sockptr(optval, devname, len))
 741		goto out;
 742
 743zero:
 744	ret = -EFAULT;
 745	if (copy_to_sockptr(optlen, &len, sizeof(int)))
 746		goto out;
 747
 748	ret = 0;
 749
 750out:
 751#endif
 752
 753	return ret;
 754}
 755
 756bool sk_mc_loop(struct sock *sk)
 757{
 758	if (dev_recursion_level())
 759		return false;
 760	if (!sk)
 761		return true;
 762	switch (sk->sk_family) {
 
 763	case AF_INET:
 764		return inet_sk(sk)->mc_loop;
 765#if IS_ENABLED(CONFIG_IPV6)
 766	case AF_INET6:
 767		return inet6_sk(sk)->mc_loop;
 768#endif
 769	}
 770	WARN_ON_ONCE(1);
 771	return true;
 772}
 773EXPORT_SYMBOL(sk_mc_loop);
 774
 775void sock_set_reuseaddr(struct sock *sk)
 776{
 777	lock_sock(sk);
 778	sk->sk_reuse = SK_CAN_REUSE;
 779	release_sock(sk);
 780}
 781EXPORT_SYMBOL(sock_set_reuseaddr);
 782
 783void sock_set_reuseport(struct sock *sk)
 784{
 785	lock_sock(sk);
 786	sk->sk_reuseport = true;
 787	release_sock(sk);
 788}
 789EXPORT_SYMBOL(sock_set_reuseport);
 790
 791void sock_no_linger(struct sock *sk)
 792{
 793	lock_sock(sk);
 794	sk->sk_lingertime = 0;
 795	sock_set_flag(sk, SOCK_LINGER);
 796	release_sock(sk);
 797}
 798EXPORT_SYMBOL(sock_no_linger);
 799
 800void sock_set_priority(struct sock *sk, u32 priority)
 801{
 802	lock_sock(sk);
 803	sk->sk_priority = priority;
 804	release_sock(sk);
 805}
 806EXPORT_SYMBOL(sock_set_priority);
 807
 808void sock_set_sndtimeo(struct sock *sk, s64 secs)
 809{
 810	lock_sock(sk);
 811	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
 812		sk->sk_sndtimeo = secs * HZ;
 813	else
 814		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
 815	release_sock(sk);
 816}
 817EXPORT_SYMBOL(sock_set_sndtimeo);
 818
 819static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
 820{
 821	if (val)  {
 822		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
 823		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
 824		sock_set_flag(sk, SOCK_RCVTSTAMP);
 825		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 826	} else {
 827		sock_reset_flag(sk, SOCK_RCVTSTAMP);
 828		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 829	}
 830}
 831
 832void sock_enable_timestamps(struct sock *sk)
 833{
 834	lock_sock(sk);
 835	__sock_set_timestamps(sk, true, false, true);
 836	release_sock(sk);
 837}
 838EXPORT_SYMBOL(sock_enable_timestamps);
 839
 840void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
 841{
 842	switch (optname) {
 843	case SO_TIMESTAMP_OLD:
 844		__sock_set_timestamps(sk, valbool, false, false);
 845		break;
 846	case SO_TIMESTAMP_NEW:
 847		__sock_set_timestamps(sk, valbool, true, false);
 848		break;
 849	case SO_TIMESTAMPNS_OLD:
 850		__sock_set_timestamps(sk, valbool, false, true);
 851		break;
 852	case SO_TIMESTAMPNS_NEW:
 853		__sock_set_timestamps(sk, valbool, true, true);
 854		break;
 855	}
 856}
 857
 858static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
 859{
 860	struct net *net = sock_net(sk);
 861	struct net_device *dev = NULL;
 862	bool match = false;
 863	int *vclock_index;
 864	int i, num;
 865
 866	if (sk->sk_bound_dev_if)
 867		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
 868
 869	if (!dev) {
 870		pr_err("%s: sock not bind to device\n", __func__);
 871		return -EOPNOTSUPP;
 872	}
 873
 874	num = ethtool_get_phc_vclocks(dev, &vclock_index);
 875	dev_put(dev);
 876
 877	for (i = 0; i < num; i++) {
 878		if (*(vclock_index + i) == phc_index) {
 879			match = true;
 880			break;
 881		}
 882	}
 883
 884	if (num > 0)
 885		kfree(vclock_index);
 886
 887	if (!match)
 888		return -EINVAL;
 889
 890	sk->sk_bind_phc = phc_index;
 891
 892	return 0;
 893}
 894
 895int sock_set_timestamping(struct sock *sk, int optname,
 896			  struct so_timestamping timestamping)
 897{
 898	int val = timestamping.flags;
 899	int ret;
 900
 901	if (val & ~SOF_TIMESTAMPING_MASK)
 902		return -EINVAL;
 903
 904	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
 905	    !(val & SOF_TIMESTAMPING_OPT_ID))
 906		return -EINVAL;
 907
 908	if (val & SOF_TIMESTAMPING_OPT_ID &&
 909	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
 910		if (sk_is_tcp(sk)) {
 911			if ((1 << sk->sk_state) &
 912			    (TCPF_CLOSE | TCPF_LISTEN))
 913				return -EINVAL;
 914			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
 915				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
 916			else
 917				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
 918		} else {
 919			atomic_set(&sk->sk_tskey, 0);
 920		}
 921	}
 922
 923	if (val & SOF_TIMESTAMPING_OPT_STATS &&
 924	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
 925		return -EINVAL;
 926
 927	if (val & SOF_TIMESTAMPING_BIND_PHC) {
 928		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
 929		if (ret)
 930			return ret;
 931	}
 932
 933	sk->sk_tsflags = val;
 934	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
 935
 936	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
 937		sock_enable_timestamp(sk,
 938				      SOCK_TIMESTAMPING_RX_SOFTWARE);
 939	else
 940		sock_disable_timestamp(sk,
 941				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
 942	return 0;
 943}
 944
 945void sock_set_keepalive(struct sock *sk)
 946{
 947	lock_sock(sk);
 948	if (sk->sk_prot->keepalive)
 949		sk->sk_prot->keepalive(sk, true);
 950	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
 951	release_sock(sk);
 952}
 953EXPORT_SYMBOL(sock_set_keepalive);
 954
 955static void __sock_set_rcvbuf(struct sock *sk, int val)
 956{
 957	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
 958	 * as a negative value.
 959	 */
 960	val = min_t(int, val, INT_MAX / 2);
 961	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 962
 963	/* We double it on the way in to account for "struct sk_buff" etc.
 964	 * overhead.   Applications assume that the SO_RCVBUF setting they make
 965	 * will allow that much actual data to be received on that socket.
 966	 *
 967	 * Applications are unaware that "struct sk_buff" and other overheads
 968	 * allocate from the receive buffer during socket buffer allocation.
 969	 *
 970	 * And after considering the possible alternatives, returning the value
 971	 * we actually used in getsockopt is the most desirable behavior.
 972	 */
 973	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
 974}
 975
 976void sock_set_rcvbuf(struct sock *sk, int val)
 977{
 978	lock_sock(sk);
 979	__sock_set_rcvbuf(sk, val);
 980	release_sock(sk);
 981}
 982EXPORT_SYMBOL(sock_set_rcvbuf);
 983
 984static void __sock_set_mark(struct sock *sk, u32 val)
 985{
 986	if (val != sk->sk_mark) {
 987		sk->sk_mark = val;
 988		sk_dst_reset(sk);
 989	}
 990}
 991
 992void sock_set_mark(struct sock *sk, u32 val)
 993{
 994	lock_sock(sk);
 995	__sock_set_mark(sk, val);
 996	release_sock(sk);
 997}
 998EXPORT_SYMBOL(sock_set_mark);
 999
1000static void sock_release_reserved_memory(struct sock *sk, int bytes)
1001{
1002	/* Round down bytes to multiple of pages */
1003	bytes = round_down(bytes, PAGE_SIZE);
1004
1005	WARN_ON(bytes > sk->sk_reserved_mem);
1006	sk->sk_reserved_mem -= bytes;
1007	sk_mem_reclaim(sk);
1008}
1009
1010static int sock_reserve_memory(struct sock *sk, int bytes)
1011{
1012	long allocated;
1013	bool charged;
1014	int pages;
1015
1016	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1017		return -EOPNOTSUPP;
1018
1019	if (!bytes)
1020		return 0;
1021
1022	pages = sk_mem_pages(bytes);
1023
1024	/* pre-charge to memcg */
1025	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1026					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1027	if (!charged)
1028		return -ENOMEM;
1029
1030	/* pre-charge to forward_alloc */
1031	sk_memory_allocated_add(sk, pages);
1032	allocated = sk_memory_allocated(sk);
1033	/* If the system goes into memory pressure with this
1034	 * precharge, give up and return error.
1035	 */
1036	if (allocated > sk_prot_mem_limits(sk, 1)) {
1037		sk_memory_allocated_sub(sk, pages);
1038		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1039		return -ENOMEM;
1040	}
1041	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1042
1043	sk->sk_reserved_mem += pages << PAGE_SHIFT;
 
1044
1045	return 0;
1046}
1047
1048void sockopt_lock_sock(struct sock *sk)
1049{
1050	/* When current->bpf_ctx is set, the setsockopt is called from
1051	 * a bpf prog.  bpf has ensured the sk lock has been
1052	 * acquired before calling setsockopt().
1053	 */
1054	if (has_current_bpf_ctx())
1055		return;
1056
1057	lock_sock(sk);
1058}
1059EXPORT_SYMBOL(sockopt_lock_sock);
1060
1061void sockopt_release_sock(struct sock *sk)
1062{
1063	if (has_current_bpf_ctx())
1064		return;
1065
1066	release_sock(sk);
1067}
1068EXPORT_SYMBOL(sockopt_release_sock);
1069
1070bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1071{
1072	return has_current_bpf_ctx() || ns_capable(ns, cap);
1073}
1074EXPORT_SYMBOL(sockopt_ns_capable);
1075
1076bool sockopt_capable(int cap)
1077{
1078	return has_current_bpf_ctx() || capable(cap);
1079}
1080EXPORT_SYMBOL(sockopt_capable);
1081
1082/*
1083 *	This is meant for all protocols to use and covers goings on
1084 *	at the socket level. Everything here is generic.
1085 */
1086
1087int sk_setsockopt(struct sock *sk, int level, int optname,
1088		  sockptr_t optval, unsigned int optlen)
1089{
1090	struct so_timestamping timestamping;
1091	struct socket *sock = sk->sk_socket;
1092	struct sock_txtime sk_txtime;
1093	int val;
1094	int valbool;
1095	struct linger ling;
1096	int ret = 0;
1097
1098	/*
1099	 *	Options without arguments
1100	 */
1101
1102	if (optname == SO_BINDTODEVICE)
1103		return sock_setbindtodevice(sk, optval, optlen);
1104
1105	if (optlen < sizeof(int))
1106		return -EINVAL;
1107
1108	if (copy_from_sockptr(&val, optval, sizeof(val)))
1109		return -EFAULT;
1110
1111	valbool = val ? 1 : 0;
1112
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1113	sockopt_lock_sock(sk);
1114
1115	switch (optname) {
1116	case SO_DEBUG:
1117		if (val && !sockopt_capable(CAP_NET_ADMIN))
1118			ret = -EACCES;
1119		else
1120			sock_valbool_flag(sk, SOCK_DBG, valbool);
1121		break;
1122	case SO_REUSEADDR:
1123		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1124		break;
1125	case SO_REUSEPORT:
1126		sk->sk_reuseport = valbool;
1127		break;
1128	case SO_TYPE:
1129	case SO_PROTOCOL:
1130	case SO_DOMAIN:
1131	case SO_ERROR:
1132		ret = -ENOPROTOOPT;
1133		break;
1134	case SO_DONTROUTE:
1135		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1136		sk_dst_reset(sk);
1137		break;
1138	case SO_BROADCAST:
1139		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1140		break;
1141	case SO_SNDBUF:
1142		/* Don't error on this BSD doesn't and if you think
1143		 * about it this is right. Otherwise apps have to
1144		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1145		 * are treated in BSD as hints
1146		 */
1147		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1148set_sndbuf:
1149		/* Ensure val * 2 fits into an int, to prevent max_t()
1150		 * from treating it as a negative value.
1151		 */
1152		val = min_t(int, val, INT_MAX / 2);
1153		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1154		WRITE_ONCE(sk->sk_sndbuf,
1155			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1156		/* Wake up sending tasks if we upped the value. */
1157		sk->sk_write_space(sk);
1158		break;
1159
1160	case SO_SNDBUFFORCE:
1161		if (!sockopt_capable(CAP_NET_ADMIN)) {
1162			ret = -EPERM;
1163			break;
1164		}
1165
1166		/* No negative values (to prevent underflow, as val will be
1167		 * multiplied by 2).
1168		 */
1169		if (val < 0)
1170			val = 0;
1171		goto set_sndbuf;
1172
1173	case SO_RCVBUF:
1174		/* Don't error on this BSD doesn't and if you think
1175		 * about it this is right. Otherwise apps have to
1176		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1177		 * are treated in BSD as hints
1178		 */
1179		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1180		break;
1181
1182	case SO_RCVBUFFORCE:
1183		if (!sockopt_capable(CAP_NET_ADMIN)) {
1184			ret = -EPERM;
1185			break;
1186		}
1187
1188		/* No negative values (to prevent underflow, as val will be
1189		 * multiplied by 2).
1190		 */
1191		__sock_set_rcvbuf(sk, max(val, 0));
1192		break;
1193
1194	case SO_KEEPALIVE:
1195		if (sk->sk_prot->keepalive)
1196			sk->sk_prot->keepalive(sk, valbool);
1197		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1198		break;
1199
1200	case SO_OOBINLINE:
1201		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1202		break;
1203
1204	case SO_NO_CHECK:
1205		sk->sk_no_check_tx = valbool;
1206		break;
1207
1208	case SO_PRIORITY:
1209		if ((val >= 0 && val <= 6) ||
1210		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1211		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1212			sk->sk_priority = val;
1213		else
1214			ret = -EPERM;
1215		break;
1216
1217	case SO_LINGER:
1218		if (optlen < sizeof(ling)) {
1219			ret = -EINVAL;	/* 1003.1g */
1220			break;
1221		}
1222		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1223			ret = -EFAULT;
1224			break;
1225		}
1226		if (!ling.l_onoff)
1227			sock_reset_flag(sk, SOCK_LINGER);
1228		else {
1229#if (BITS_PER_LONG == 32)
1230			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1231				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
 
1232			else
1233#endif
1234				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1235			sock_set_flag(sk, SOCK_LINGER);
1236		}
1237		break;
1238
1239	case SO_BSDCOMPAT:
1240		break;
1241
1242	case SO_PASSCRED:
1243		if (valbool)
1244			set_bit(SOCK_PASSCRED, &sock->flags);
1245		else
1246			clear_bit(SOCK_PASSCRED, &sock->flags);
1247		break;
1248
1249	case SO_TIMESTAMP_OLD:
1250	case SO_TIMESTAMP_NEW:
1251	case SO_TIMESTAMPNS_OLD:
1252	case SO_TIMESTAMPNS_NEW:
1253		sock_set_timestamp(sk, optname, valbool);
1254		break;
1255
1256	case SO_TIMESTAMPING_NEW:
1257	case SO_TIMESTAMPING_OLD:
1258		if (optlen == sizeof(timestamping)) {
1259			if (copy_from_sockptr(&timestamping, optval,
1260					      sizeof(timestamping))) {
1261				ret = -EFAULT;
1262				break;
1263			}
1264		} else {
1265			memset(&timestamping, 0, sizeof(timestamping));
1266			timestamping.flags = val;
1267		}
1268		ret = sock_set_timestamping(sk, optname, timestamping);
1269		break;
1270
1271	case SO_RCVLOWAT:
 
 
 
1272		if (val < 0)
1273			val = INT_MAX;
1274		if (sock && sock->ops->set_rcvlowat)
1275			ret = sock->ops->set_rcvlowat(sk, val);
 
 
1276		else
1277			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1278		break;
1279
1280	case SO_RCVTIMEO_OLD:
1281	case SO_RCVTIMEO_NEW:
1282		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1283				       optlen, optname == SO_RCVTIMEO_OLD);
1284		break;
1285
1286	case SO_SNDTIMEO_OLD:
1287	case SO_SNDTIMEO_NEW:
1288		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1289				       optlen, optname == SO_SNDTIMEO_OLD);
1290		break;
1291
1292	case SO_ATTACH_FILTER: {
1293		struct sock_fprog fprog;
1294
1295		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1296		if (!ret)
1297			ret = sk_attach_filter(&fprog, sk);
1298		break;
1299	}
1300	case SO_ATTACH_BPF:
1301		ret = -EINVAL;
1302		if (optlen == sizeof(u32)) {
1303			u32 ufd;
1304
1305			ret = -EFAULT;
1306			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1307				break;
1308
1309			ret = sk_attach_bpf(ufd, sk);
1310		}
1311		break;
1312
1313	case SO_ATTACH_REUSEPORT_CBPF: {
1314		struct sock_fprog fprog;
1315
1316		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1317		if (!ret)
1318			ret = sk_reuseport_attach_filter(&fprog, sk);
1319		break;
1320	}
1321	case SO_ATTACH_REUSEPORT_EBPF:
1322		ret = -EINVAL;
1323		if (optlen == sizeof(u32)) {
1324			u32 ufd;
1325
1326			ret = -EFAULT;
1327			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1328				break;
1329
1330			ret = sk_reuseport_attach_bpf(ufd, sk);
1331		}
1332		break;
1333
1334	case SO_DETACH_REUSEPORT_BPF:
1335		ret = reuseport_detach_prog(sk);
1336		break;
1337
1338	case SO_DETACH_FILTER:
1339		ret = sk_detach_filter(sk);
1340		break;
1341
1342	case SO_LOCK_FILTER:
1343		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1344			ret = -EPERM;
1345		else
1346			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1347		break;
1348
1349	case SO_PASSSEC:
1350		if (valbool)
1351			set_bit(SOCK_PASSSEC, &sock->flags);
1352		else
1353			clear_bit(SOCK_PASSSEC, &sock->flags);
1354		break;
1355	case SO_MARK:
1356		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1357		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1358			ret = -EPERM;
1359			break;
1360		}
1361
1362		__sock_set_mark(sk, val);
1363		break;
1364	case SO_RCVMARK:
1365		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1366		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1367			ret = -EPERM;
1368			break;
1369		}
1370
1371		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1372		break;
1373
1374	case SO_RXQ_OVFL:
1375		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1376		break;
1377
1378	case SO_WIFI_STATUS:
1379		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1380		break;
1381
1382	case SO_PEEK_OFF:
1383		if (sock->ops->set_peek_off)
1384			ret = sock->ops->set_peek_off(sk, val);
1385		else
1386			ret = -EOPNOTSUPP;
1387		break;
1388
1389	case SO_NOFCS:
1390		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1391		break;
1392
1393	case SO_SELECT_ERR_QUEUE:
1394		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1395		break;
1396
1397#ifdef CONFIG_NET_RX_BUSY_POLL
1398	case SO_BUSY_POLL:
1399		/* allow unprivileged users to decrease the value */
1400		if ((val > sk->sk_ll_usec) && !sockopt_capable(CAP_NET_ADMIN))
1401			ret = -EPERM;
1402		else {
1403			if (val < 0)
1404				ret = -EINVAL;
1405			else
1406				WRITE_ONCE(sk->sk_ll_usec, val);
1407		}
1408		break;
1409	case SO_PREFER_BUSY_POLL:
1410		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1411			ret = -EPERM;
1412		else
1413			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1414		break;
1415	case SO_BUSY_POLL_BUDGET:
1416		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1417			ret = -EPERM;
1418		} else {
1419			if (val < 0 || val > U16_MAX)
1420				ret = -EINVAL;
1421			else
1422				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1423		}
1424		break;
1425#endif
1426
1427	case SO_MAX_PACING_RATE:
1428		{
1429		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1430
1431		if (sizeof(ulval) != sizeof(val) &&
1432		    optlen >= sizeof(ulval) &&
1433		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1434			ret = -EFAULT;
1435			break;
1436		}
1437		if (ulval != ~0UL)
1438			cmpxchg(&sk->sk_pacing_status,
1439				SK_PACING_NONE,
1440				SK_PACING_NEEDED);
1441		sk->sk_max_pacing_rate = ulval;
1442		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1443		break;
1444		}
1445	case SO_INCOMING_CPU:
1446		reuseport_update_incoming_cpu(sk, val);
1447		break;
1448
1449	case SO_CNX_ADVICE:
1450		if (val == 1)
1451			dst_negative_advice(sk);
1452		break;
1453
1454	case SO_ZEROCOPY:
1455		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1456			if (!(sk_is_tcp(sk) ||
1457			      (sk->sk_type == SOCK_DGRAM &&
1458			       sk->sk_protocol == IPPROTO_UDP)))
1459				ret = -EOPNOTSUPP;
1460		} else if (sk->sk_family != PF_RDS) {
1461			ret = -EOPNOTSUPP;
1462		}
1463		if (!ret) {
1464			if (val < 0 || val > 1)
1465				ret = -EINVAL;
1466			else
1467				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1468		}
1469		break;
1470
1471	case SO_TXTIME:
1472		if (optlen != sizeof(struct sock_txtime)) {
1473			ret = -EINVAL;
1474			break;
1475		} else if (copy_from_sockptr(&sk_txtime, optval,
1476			   sizeof(struct sock_txtime))) {
1477			ret = -EFAULT;
1478			break;
1479		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1480			ret = -EINVAL;
1481			break;
1482		}
1483		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1484		 * scheduler has enough safe guards.
1485		 */
1486		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1487		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1488			ret = -EPERM;
1489			break;
1490		}
1491		sock_valbool_flag(sk, SOCK_TXTIME, true);
1492		sk->sk_clockid = sk_txtime.clockid;
1493		sk->sk_txtime_deadline_mode =
1494			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1495		sk->sk_txtime_report_errors =
1496			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1497		break;
1498
1499	case SO_BINDTOIFINDEX:
1500		ret = sock_bindtoindex_locked(sk, val);
1501		break;
1502
1503	case SO_BUF_LOCK:
1504		if (val & ~SOCK_BUF_LOCK_MASK) {
1505			ret = -EINVAL;
1506			break;
1507		}
1508		sk->sk_userlocks = val | (sk->sk_userlocks &
1509					  ~SOCK_BUF_LOCK_MASK);
1510		break;
1511
1512	case SO_RESERVE_MEM:
1513	{
1514		int delta;
1515
1516		if (val < 0) {
1517			ret = -EINVAL;
1518			break;
1519		}
1520
1521		delta = val - sk->sk_reserved_mem;
1522		if (delta < 0)
1523			sock_release_reserved_memory(sk, -delta);
1524		else
1525			ret = sock_reserve_memory(sk, delta);
1526		break;
1527	}
1528
1529	case SO_TXREHASH:
1530		if (val < -1 || val > 1) {
1531			ret = -EINVAL;
1532			break;
1533		}
1534		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1535			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1536		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1537		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1538		break;
1539
1540	default:
1541		ret = -ENOPROTOOPT;
1542		break;
1543	}
1544	sockopt_release_sock(sk);
1545	return ret;
1546}
1547
1548int sock_setsockopt(struct socket *sock, int level, int optname,
1549		    sockptr_t optval, unsigned int optlen)
1550{
1551	return sk_setsockopt(sock->sk, level, optname,
1552			     optval, optlen);
1553}
1554EXPORT_SYMBOL(sock_setsockopt);
1555
1556static const struct cred *sk_get_peer_cred(struct sock *sk)
1557{
1558	const struct cred *cred;
1559
1560	spin_lock(&sk->sk_peer_lock);
1561	cred = get_cred(sk->sk_peer_cred);
1562	spin_unlock(&sk->sk_peer_lock);
1563
1564	return cred;
1565}
1566
1567static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1568			  struct ucred *ucred)
1569{
1570	ucred->pid = pid_vnr(pid);
1571	ucred->uid = ucred->gid = -1;
1572	if (cred) {
1573		struct user_namespace *current_ns = current_user_ns();
1574
1575		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1576		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1577	}
1578}
1579
1580static int groups_to_user(sockptr_t dst, const struct group_info *src)
1581{
1582	struct user_namespace *user_ns = current_user_ns();
1583	int i;
1584
1585	for (i = 0; i < src->ngroups; i++) {
1586		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1587
1588		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1589			return -EFAULT;
1590	}
1591
1592	return 0;
1593}
1594
1595int sk_getsockopt(struct sock *sk, int level, int optname,
1596		  sockptr_t optval, sockptr_t optlen)
1597{
1598	struct socket *sock = sk->sk_socket;
1599
1600	union {
1601		int val;
1602		u64 val64;
1603		unsigned long ulval;
1604		struct linger ling;
1605		struct old_timeval32 tm32;
1606		struct __kernel_old_timeval tm;
1607		struct  __kernel_sock_timeval stm;
1608		struct sock_txtime txtime;
1609		struct so_timestamping timestamping;
1610	} v;
1611
1612	int lv = sizeof(int);
1613	int len;
1614
1615	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1616		return -EFAULT;
1617	if (len < 0)
1618		return -EINVAL;
1619
1620	memset(&v, 0, sizeof(v));
1621
1622	switch (optname) {
1623	case SO_DEBUG:
1624		v.val = sock_flag(sk, SOCK_DBG);
1625		break;
1626
1627	case SO_DONTROUTE:
1628		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1629		break;
1630
1631	case SO_BROADCAST:
1632		v.val = sock_flag(sk, SOCK_BROADCAST);
1633		break;
1634
1635	case SO_SNDBUF:
1636		v.val = sk->sk_sndbuf;
1637		break;
1638
1639	case SO_RCVBUF:
1640		v.val = sk->sk_rcvbuf;
1641		break;
1642
1643	case SO_REUSEADDR:
1644		v.val = sk->sk_reuse;
1645		break;
1646
1647	case SO_REUSEPORT:
1648		v.val = sk->sk_reuseport;
1649		break;
1650
1651	case SO_KEEPALIVE:
1652		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1653		break;
1654
1655	case SO_TYPE:
1656		v.val = sk->sk_type;
1657		break;
1658
1659	case SO_PROTOCOL:
1660		v.val = sk->sk_protocol;
1661		break;
1662
1663	case SO_DOMAIN:
1664		v.val = sk->sk_family;
1665		break;
1666
1667	case SO_ERROR:
1668		v.val = -sock_error(sk);
1669		if (v.val == 0)
1670			v.val = xchg(&sk->sk_err_soft, 0);
1671		break;
1672
1673	case SO_OOBINLINE:
1674		v.val = sock_flag(sk, SOCK_URGINLINE);
1675		break;
1676
1677	case SO_NO_CHECK:
1678		v.val = sk->sk_no_check_tx;
1679		break;
1680
1681	case SO_PRIORITY:
1682		v.val = sk->sk_priority;
1683		break;
1684
1685	case SO_LINGER:
1686		lv		= sizeof(v.ling);
1687		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1688		v.ling.l_linger	= sk->sk_lingertime / HZ;
1689		break;
1690
1691	case SO_BSDCOMPAT:
1692		break;
1693
1694	case SO_TIMESTAMP_OLD:
1695		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1696				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1697				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1698		break;
1699
1700	case SO_TIMESTAMPNS_OLD:
1701		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1702		break;
1703
1704	case SO_TIMESTAMP_NEW:
1705		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1706		break;
1707
1708	case SO_TIMESTAMPNS_NEW:
1709		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1710		break;
1711
1712	case SO_TIMESTAMPING_OLD:
 
1713		lv = sizeof(v.timestamping);
1714		v.timestamping.flags = sk->sk_tsflags;
1715		v.timestamping.bind_phc = sk->sk_bind_phc;
 
 
 
 
 
 
1716		break;
1717
1718	case SO_RCVTIMEO_OLD:
1719	case SO_RCVTIMEO_NEW:
1720		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
 
1721		break;
1722
1723	case SO_SNDTIMEO_OLD:
1724	case SO_SNDTIMEO_NEW:
1725		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
 
1726		break;
1727
1728	case SO_RCVLOWAT:
1729		v.val = sk->sk_rcvlowat;
1730		break;
1731
1732	case SO_SNDLOWAT:
1733		v.val = 1;
1734		break;
1735
1736	case SO_PASSCRED:
1737		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1738		break;
1739
 
 
 
 
1740	case SO_PEERCRED:
1741	{
1742		struct ucred peercred;
1743		if (len > sizeof(peercred))
1744			len = sizeof(peercred);
1745
1746		spin_lock(&sk->sk_peer_lock);
1747		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1748		spin_unlock(&sk->sk_peer_lock);
1749
1750		if (copy_to_sockptr(optval, &peercred, len))
1751			return -EFAULT;
1752		goto lenout;
1753	}
1754
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1755	case SO_PEERGROUPS:
1756	{
1757		const struct cred *cred;
1758		int ret, n;
1759
1760		cred = sk_get_peer_cred(sk);
1761		if (!cred)
1762			return -ENODATA;
1763
1764		n = cred->group_info->ngroups;
1765		if (len < n * sizeof(gid_t)) {
1766			len = n * sizeof(gid_t);
1767			put_cred(cred);
1768			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1769		}
1770		len = n * sizeof(gid_t);
1771
1772		ret = groups_to_user(optval, cred->group_info);
1773		put_cred(cred);
1774		if (ret)
1775			return ret;
1776		goto lenout;
1777	}
1778
1779	case SO_PEERNAME:
1780	{
1781		char address[128];
1782
1783		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1784		if (lv < 0)
1785			return -ENOTCONN;
1786		if (lv < len)
1787			return -EINVAL;
1788		if (copy_to_sockptr(optval, address, len))
1789			return -EFAULT;
1790		goto lenout;
1791	}
1792
1793	/* Dubious BSD thing... Probably nobody even uses it, but
1794	 * the UNIX standard wants it for whatever reason... -DaveM
1795	 */
1796	case SO_ACCEPTCONN:
1797		v.val = sk->sk_state == TCP_LISTEN;
1798		break;
1799
1800	case SO_PASSSEC:
1801		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1802		break;
1803
1804	case SO_PEERSEC:
1805		return security_socket_getpeersec_stream(sock,
1806							 optval, optlen, len);
1807
1808	case SO_MARK:
1809		v.val = sk->sk_mark;
1810		break;
1811
1812	case SO_RCVMARK:
1813		v.val = sock_flag(sk, SOCK_RCVMARK);
1814		break;
1815
1816	case SO_RXQ_OVFL:
1817		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1818		break;
1819
1820	case SO_WIFI_STATUS:
1821		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1822		break;
1823
1824	case SO_PEEK_OFF:
1825		if (!sock->ops->set_peek_off)
1826			return -EOPNOTSUPP;
1827
1828		v.val = sk->sk_peek_off;
1829		break;
1830	case SO_NOFCS:
1831		v.val = sock_flag(sk, SOCK_NOFCS);
1832		break;
1833
1834	case SO_BINDTODEVICE:
1835		return sock_getbindtodevice(sk, optval, optlen, len);
1836
1837	case SO_GET_FILTER:
1838		len = sk_get_filter(sk, optval, len);
1839		if (len < 0)
1840			return len;
1841
1842		goto lenout;
1843
1844	case SO_LOCK_FILTER:
1845		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1846		break;
1847
1848	case SO_BPF_EXTENSIONS:
1849		v.val = bpf_tell_extensions();
1850		break;
1851
1852	case SO_SELECT_ERR_QUEUE:
1853		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1854		break;
1855
1856#ifdef CONFIG_NET_RX_BUSY_POLL
1857	case SO_BUSY_POLL:
1858		v.val = sk->sk_ll_usec;
1859		break;
1860	case SO_PREFER_BUSY_POLL:
1861		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1862		break;
1863#endif
1864
1865	case SO_MAX_PACING_RATE:
 
1866		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1867			lv = sizeof(v.ulval);
1868			v.ulval = sk->sk_max_pacing_rate;
1869		} else {
1870			/* 32bit version */
1871			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
 
1872		}
1873		break;
1874
1875	case SO_INCOMING_CPU:
1876		v.val = READ_ONCE(sk->sk_incoming_cpu);
1877		break;
1878
1879	case SO_MEMINFO:
1880	{
1881		u32 meminfo[SK_MEMINFO_VARS];
1882
1883		sk_get_meminfo(sk, meminfo);
1884
1885		len = min_t(unsigned int, len, sizeof(meminfo));
1886		if (copy_to_sockptr(optval, &meminfo, len))
1887			return -EFAULT;
1888
1889		goto lenout;
1890	}
1891
1892#ifdef CONFIG_NET_RX_BUSY_POLL
1893	case SO_INCOMING_NAPI_ID:
1894		v.val = READ_ONCE(sk->sk_napi_id);
1895
1896		/* aggregate non-NAPI IDs down to 0 */
1897		if (v.val < MIN_NAPI_ID)
1898			v.val = 0;
1899
1900		break;
1901#endif
1902
1903	case SO_COOKIE:
1904		lv = sizeof(u64);
1905		if (len < lv)
1906			return -EINVAL;
1907		v.val64 = sock_gen_cookie(sk);
1908		break;
1909
1910	case SO_ZEROCOPY:
1911		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1912		break;
1913
1914	case SO_TXTIME:
1915		lv = sizeof(v.txtime);
1916		v.txtime.clockid = sk->sk_clockid;
1917		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1918				  SOF_TXTIME_DEADLINE_MODE : 0;
1919		v.txtime.flags |= sk->sk_txtime_report_errors ?
1920				  SOF_TXTIME_REPORT_ERRORS : 0;
1921		break;
1922
1923	case SO_BINDTOIFINDEX:
1924		v.val = READ_ONCE(sk->sk_bound_dev_if);
1925		break;
1926
1927	case SO_NETNS_COOKIE:
1928		lv = sizeof(u64);
1929		if (len != lv)
1930			return -EINVAL;
1931		v.val64 = sock_net(sk)->net_cookie;
1932		break;
1933
1934	case SO_BUF_LOCK:
1935		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1936		break;
1937
1938	case SO_RESERVE_MEM:
1939		v.val = sk->sk_reserved_mem;
1940		break;
1941
1942	case SO_TXREHASH:
1943		v.val = sk->sk_txrehash;
 
1944		break;
1945
1946	default:
1947		/* We implement the SO_SNDLOWAT etc to not be settable
1948		 * (1003.1g 7).
1949		 */
1950		return -ENOPROTOOPT;
1951	}
1952
1953	if (len > lv)
1954		len = lv;
1955	if (copy_to_sockptr(optval, &v, len))
1956		return -EFAULT;
1957lenout:
1958	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1959		return -EFAULT;
1960	return 0;
1961}
1962
1963int sock_getsockopt(struct socket *sock, int level, int optname,
1964		    char __user *optval, int __user *optlen)
1965{
1966	return sk_getsockopt(sock->sk, level, optname,
1967			     USER_SOCKPTR(optval),
1968			     USER_SOCKPTR(optlen));
1969}
1970
1971/*
1972 * Initialize an sk_lock.
1973 *
1974 * (We also register the sk_lock with the lock validator.)
1975 */
1976static inline void sock_lock_init(struct sock *sk)
1977{
1978	if (sk->sk_kern_sock)
1979		sock_lock_init_class_and_name(
1980			sk,
1981			af_family_kern_slock_key_strings[sk->sk_family],
1982			af_family_kern_slock_keys + sk->sk_family,
1983			af_family_kern_key_strings[sk->sk_family],
1984			af_family_kern_keys + sk->sk_family);
1985	else
1986		sock_lock_init_class_and_name(
1987			sk,
1988			af_family_slock_key_strings[sk->sk_family],
1989			af_family_slock_keys + sk->sk_family,
1990			af_family_key_strings[sk->sk_family],
1991			af_family_keys + sk->sk_family);
1992}
1993
1994/*
1995 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1996 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1997 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1998 */
1999static void sock_copy(struct sock *nsk, const struct sock *osk)
2000{
2001	const struct proto *prot = READ_ONCE(osk->sk_prot);
2002#ifdef CONFIG_SECURITY_NETWORK
2003	void *sptr = nsk->sk_security;
2004#endif
2005
2006	/* If we move sk_tx_queue_mapping out of the private section,
2007	 * we must check if sk_tx_queue_clear() is called after
2008	 * sock_copy() in sk_clone_lock().
2009	 */
2010	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2011		     offsetof(struct sock, sk_dontcopy_begin) ||
2012		     offsetof(struct sock, sk_tx_queue_mapping) >=
2013		     offsetof(struct sock, sk_dontcopy_end));
2014
2015	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2016
2017	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2018	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2019
2020#ifdef CONFIG_SECURITY_NETWORK
2021	nsk->sk_security = sptr;
2022	security_sk_clone(osk, nsk);
2023#endif
2024}
2025
2026static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2027		int family)
2028{
2029	struct sock *sk;
2030	struct kmem_cache *slab;
2031
2032	slab = prot->slab;
2033	if (slab != NULL) {
2034		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2035		if (!sk)
2036			return sk;
2037		if (want_init_on_alloc(priority))
2038			sk_prot_clear_nulls(sk, prot->obj_size);
2039	} else
2040		sk = kmalloc(prot->obj_size, priority);
2041
2042	if (sk != NULL) {
2043		if (security_sk_alloc(sk, family, priority))
2044			goto out_free;
2045
2046		if (!try_module_get(prot->owner))
2047			goto out_free_sec;
2048	}
2049
2050	return sk;
2051
2052out_free_sec:
2053	security_sk_free(sk);
2054out_free:
2055	if (slab != NULL)
2056		kmem_cache_free(slab, sk);
2057	else
2058		kfree(sk);
2059	return NULL;
2060}
2061
2062static void sk_prot_free(struct proto *prot, struct sock *sk)
2063{
2064	struct kmem_cache *slab;
2065	struct module *owner;
2066
2067	owner = prot->owner;
2068	slab = prot->slab;
2069
2070	cgroup_sk_free(&sk->sk_cgrp_data);
2071	mem_cgroup_sk_free(sk);
2072	security_sk_free(sk);
2073	if (slab != NULL)
2074		kmem_cache_free(slab, sk);
2075	else
2076		kfree(sk);
2077	module_put(owner);
2078}
2079
2080/**
2081 *	sk_alloc - All socket objects are allocated here
2082 *	@net: the applicable net namespace
2083 *	@family: protocol family
2084 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2085 *	@prot: struct proto associated with this new sock instance
2086 *	@kern: is this to be a kernel socket?
2087 */
2088struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2089		      struct proto *prot, int kern)
2090{
2091	struct sock *sk;
2092
2093	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2094	if (sk) {
2095		sk->sk_family = family;
2096		/*
2097		 * See comment in struct sock definition to understand
2098		 * why we need sk_prot_creator -acme
2099		 */
2100		sk->sk_prot = sk->sk_prot_creator = prot;
2101		sk->sk_kern_sock = kern;
2102		sock_lock_init(sk);
2103		sk->sk_net_refcnt = kern ? 0 : 1;
2104		if (likely(sk->sk_net_refcnt)) {
2105			get_net_track(net, &sk->ns_tracker, priority);
2106			sock_inuse_add(net, 1);
2107		} else {
2108			__netns_tracker_alloc(net, &sk->ns_tracker,
2109					      false, priority);
2110		}
2111
2112		sock_net_set(sk, net);
2113		refcount_set(&sk->sk_wmem_alloc, 1);
2114
2115		mem_cgroup_sk_alloc(sk);
2116		cgroup_sk_alloc(&sk->sk_cgrp_data);
2117		sock_update_classid(&sk->sk_cgrp_data);
2118		sock_update_netprioidx(&sk->sk_cgrp_data);
2119		sk_tx_queue_clear(sk);
2120	}
2121
2122	return sk;
2123}
2124EXPORT_SYMBOL(sk_alloc);
2125
2126/* Sockets having SOCK_RCU_FREE will call this function after one RCU
2127 * grace period. This is the case for UDP sockets and TCP listeners.
2128 */
2129static void __sk_destruct(struct rcu_head *head)
2130{
2131	struct sock *sk = container_of(head, struct sock, sk_rcu);
2132	struct sk_filter *filter;
2133
2134	if (sk->sk_destruct)
2135		sk->sk_destruct(sk);
2136
2137	filter = rcu_dereference_check(sk->sk_filter,
2138				       refcount_read(&sk->sk_wmem_alloc) == 0);
2139	if (filter) {
2140		sk_filter_uncharge(sk, filter);
2141		RCU_INIT_POINTER(sk->sk_filter, NULL);
2142	}
2143
2144	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2145
2146#ifdef CONFIG_BPF_SYSCALL
2147	bpf_sk_storage_free(sk);
2148#endif
2149
2150	if (atomic_read(&sk->sk_omem_alloc))
2151		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2152			 __func__, atomic_read(&sk->sk_omem_alloc));
2153
2154	if (sk->sk_frag.page) {
2155		put_page(sk->sk_frag.page);
2156		sk->sk_frag.page = NULL;
2157	}
2158
2159	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2160	put_cred(sk->sk_peer_cred);
2161	put_pid(sk->sk_peer_pid);
2162
2163	if (likely(sk->sk_net_refcnt))
2164		put_net_track(sock_net(sk), &sk->ns_tracker);
2165	else
2166		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2167
2168	sk_prot_free(sk->sk_prot_creator, sk);
2169}
2170
2171void sk_destruct(struct sock *sk)
2172{
2173	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2174
2175	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2176		reuseport_detach_sock(sk);
2177		use_call_rcu = true;
2178	}
2179
2180	if (use_call_rcu)
2181		call_rcu(&sk->sk_rcu, __sk_destruct);
2182	else
2183		__sk_destruct(&sk->sk_rcu);
2184}
2185
2186static void __sk_free(struct sock *sk)
2187{
2188	if (likely(sk->sk_net_refcnt))
2189		sock_inuse_add(sock_net(sk), -1);
2190
2191	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2192		sock_diag_broadcast_destroy(sk);
2193	else
2194		sk_destruct(sk);
2195}
2196
2197void sk_free(struct sock *sk)
2198{
2199	/*
2200	 * We subtract one from sk_wmem_alloc and can know if
2201	 * some packets are still in some tx queue.
2202	 * If not null, sock_wfree() will call __sk_free(sk) later
2203	 */
2204	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2205		__sk_free(sk);
2206}
2207EXPORT_SYMBOL(sk_free);
2208
2209static void sk_init_common(struct sock *sk)
2210{
2211	skb_queue_head_init(&sk->sk_receive_queue);
2212	skb_queue_head_init(&sk->sk_write_queue);
2213	skb_queue_head_init(&sk->sk_error_queue);
2214
2215	rwlock_init(&sk->sk_callback_lock);
2216	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2217			af_rlock_keys + sk->sk_family,
2218			af_family_rlock_key_strings[sk->sk_family]);
2219	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2220			af_wlock_keys + sk->sk_family,
2221			af_family_wlock_key_strings[sk->sk_family]);
2222	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2223			af_elock_keys + sk->sk_family,
2224			af_family_elock_key_strings[sk->sk_family]);
2225	lockdep_set_class_and_name(&sk->sk_callback_lock,
2226			af_callback_keys + sk->sk_family,
2227			af_family_clock_key_strings[sk->sk_family]);
2228}
2229
2230/**
2231 *	sk_clone_lock - clone a socket, and lock its clone
2232 *	@sk: the socket to clone
2233 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2234 *
2235 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2236 */
2237struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2238{
2239	struct proto *prot = READ_ONCE(sk->sk_prot);
2240	struct sk_filter *filter;
2241	bool is_charged = true;
2242	struct sock *newsk;
2243
2244	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2245	if (!newsk)
2246		goto out;
2247
2248	sock_copy(newsk, sk);
2249
2250	newsk->sk_prot_creator = prot;
2251
2252	/* SANITY */
2253	if (likely(newsk->sk_net_refcnt)) {
2254		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2255		sock_inuse_add(sock_net(newsk), 1);
2256	} else {
2257		/* Kernel sockets are not elevating the struct net refcount.
2258		 * Instead, use a tracker to more easily detect if a layer
2259		 * is not properly dismantling its kernel sockets at netns
2260		 * destroy time.
2261		 */
2262		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2263				      false, priority);
2264	}
2265	sk_node_init(&newsk->sk_node);
2266	sock_lock_init(newsk);
2267	bh_lock_sock(newsk);
2268	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2269	newsk->sk_backlog.len = 0;
2270
2271	atomic_set(&newsk->sk_rmem_alloc, 0);
2272
2273	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2274	refcount_set(&newsk->sk_wmem_alloc, 1);
2275
2276	atomic_set(&newsk->sk_omem_alloc, 0);
2277	sk_init_common(newsk);
2278
2279	newsk->sk_dst_cache	= NULL;
2280	newsk->sk_dst_pending_confirm = 0;
2281	newsk->sk_wmem_queued	= 0;
2282	newsk->sk_forward_alloc = 0;
2283	newsk->sk_reserved_mem  = 0;
2284	atomic_set(&newsk->sk_drops, 0);
2285	newsk->sk_send_head	= NULL;
2286	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2287	atomic_set(&newsk->sk_zckey, 0);
2288
2289	sock_reset_flag(newsk, SOCK_DONE);
2290
2291	/* sk->sk_memcg will be populated at accept() time */
2292	newsk->sk_memcg = NULL;
2293
2294	cgroup_sk_clone(&newsk->sk_cgrp_data);
2295
2296	rcu_read_lock();
2297	filter = rcu_dereference(sk->sk_filter);
2298	if (filter != NULL)
2299		/* though it's an empty new sock, the charging may fail
2300		 * if sysctl_optmem_max was changed between creation of
2301		 * original socket and cloning
2302		 */
2303		is_charged = sk_filter_charge(newsk, filter);
2304	RCU_INIT_POINTER(newsk->sk_filter, filter);
2305	rcu_read_unlock();
2306
2307	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2308		/* We need to make sure that we don't uncharge the new
2309		 * socket if we couldn't charge it in the first place
2310		 * as otherwise we uncharge the parent's filter.
2311		 */
2312		if (!is_charged)
2313			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2314		sk_free_unlock_clone(newsk);
2315		newsk = NULL;
2316		goto out;
2317	}
2318	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2319
2320	if (bpf_sk_storage_clone(sk, newsk)) {
2321		sk_free_unlock_clone(newsk);
2322		newsk = NULL;
2323		goto out;
2324	}
2325
2326	/* Clear sk_user_data if parent had the pointer tagged
2327	 * as not suitable for copying when cloning.
2328	 */
2329	if (sk_user_data_is_nocopy(newsk))
2330		newsk->sk_user_data = NULL;
2331
2332	newsk->sk_err	   = 0;
2333	newsk->sk_err_soft = 0;
2334	newsk->sk_priority = 0;
2335	newsk->sk_incoming_cpu = raw_smp_processor_id();
2336
2337	/* Before updating sk_refcnt, we must commit prior changes to memory
2338	 * (Documentation/RCU/rculist_nulls.rst for details)
2339	 */
2340	smp_wmb();
2341	refcount_set(&newsk->sk_refcnt, 2);
2342
2343	/* Increment the counter in the same struct proto as the master
2344	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2345	 * is the same as sk->sk_prot->socks, as this field was copied
2346	 * with memcpy).
2347	 *
2348	 * This _changes_ the previous behaviour, where
2349	 * tcp_create_openreq_child always was incrementing the
2350	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2351	 * to be taken into account in all callers. -acme
2352	 */
2353	sk_refcnt_debug_inc(newsk);
2354	sk_set_socket(newsk, NULL);
2355	sk_tx_queue_clear(newsk);
2356	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2357
2358	if (newsk->sk_prot->sockets_allocated)
2359		sk_sockets_allocated_inc(newsk);
2360
2361	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2362		net_enable_timestamp();
2363out:
2364	return newsk;
2365}
2366EXPORT_SYMBOL_GPL(sk_clone_lock);
2367
2368void sk_free_unlock_clone(struct sock *sk)
2369{
2370	/* It is still raw copy of parent, so invalidate
2371	 * destructor and make plain sk_free() */
2372	sk->sk_destruct = NULL;
2373	bh_unlock_sock(sk);
2374	sk_free(sk);
2375}
2376EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2377
2378static void sk_trim_gso_size(struct sock *sk)
2379{
2380	if (sk->sk_gso_max_size <= GSO_LEGACY_MAX_SIZE)
2381		return;
 
2382#if IS_ENABLED(CONFIG_IPV6)
2383	if (sk->sk_family == AF_INET6 &&
2384	    sk_is_tcp(sk) &&
2385	    !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
2386		return;
2387#endif
2388	sk->sk_gso_max_size = GSO_LEGACY_MAX_SIZE;
 
 
 
 
 
 
2389}
2390
2391void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2392{
2393	u32 max_segs = 1;
2394
2395	sk_dst_set(sk, dst);
2396	sk->sk_route_caps = dst->dev->features;
2397	if (sk_is_tcp(sk))
2398		sk->sk_route_caps |= NETIF_F_GSO;
2399	if (sk->sk_route_caps & NETIF_F_GSO)
2400		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2401	if (unlikely(sk->sk_gso_disabled))
2402		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2403	if (sk_can_gso(sk)) {
2404		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2405			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2406		} else {
2407			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2408			/* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2409			sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2410			sk_trim_gso_size(sk);
2411			sk->sk_gso_max_size -= (MAX_TCP_HEADER + 1);
2412			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2413			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2414		}
2415	}
2416	sk->sk_gso_max_segs = max_segs;
 
2417}
2418EXPORT_SYMBOL_GPL(sk_setup_caps);
2419
2420/*
2421 *	Simple resource managers for sockets.
2422 */
2423
2424
2425/*
2426 * Write buffer destructor automatically called from kfree_skb.
2427 */
2428void sock_wfree(struct sk_buff *skb)
2429{
2430	struct sock *sk = skb->sk;
2431	unsigned int len = skb->truesize;
2432	bool free;
2433
2434	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2435		if (sock_flag(sk, SOCK_RCU_FREE) &&
2436		    sk->sk_write_space == sock_def_write_space) {
2437			rcu_read_lock();
2438			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2439			sock_def_write_space_wfree(sk);
2440			rcu_read_unlock();
2441			if (unlikely(free))
2442				__sk_free(sk);
2443			return;
2444		}
2445
2446		/*
2447		 * Keep a reference on sk_wmem_alloc, this will be released
2448		 * after sk_write_space() call
2449		 */
2450		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2451		sk->sk_write_space(sk);
2452		len = 1;
2453	}
2454	/*
2455	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2456	 * could not do because of in-flight packets
2457	 */
2458	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2459		__sk_free(sk);
2460}
2461EXPORT_SYMBOL(sock_wfree);
2462
2463/* This variant of sock_wfree() is used by TCP,
2464 * since it sets SOCK_USE_WRITE_QUEUE.
2465 */
2466void __sock_wfree(struct sk_buff *skb)
2467{
2468	struct sock *sk = skb->sk;
2469
2470	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2471		__sk_free(sk);
2472}
2473
2474void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2475{
2476	skb_orphan(skb);
2477	skb->sk = sk;
2478#ifdef CONFIG_INET
2479	if (unlikely(!sk_fullsock(sk))) {
2480		skb->destructor = sock_edemux;
2481		sock_hold(sk);
2482		return;
2483	}
2484#endif
2485	skb->destructor = sock_wfree;
2486	skb_set_hash_from_sk(skb, sk);
2487	/*
2488	 * We used to take a refcount on sk, but following operation
2489	 * is enough to guarantee sk_free() wont free this sock until
2490	 * all in-flight packets are completed
2491	 */
2492	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2493}
2494EXPORT_SYMBOL(skb_set_owner_w);
2495
2496static bool can_skb_orphan_partial(const struct sk_buff *skb)
2497{
2498#ifdef CONFIG_TLS_DEVICE
2499	/* Drivers depend on in-order delivery for crypto offload,
2500	 * partial orphan breaks out-of-order-OK logic.
2501	 */
2502	if (skb->decrypted)
2503		return false;
2504#endif
2505	return (skb->destructor == sock_wfree ||
2506		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2507}
2508
2509/* This helper is used by netem, as it can hold packets in its
2510 * delay queue. We want to allow the owner socket to send more
2511 * packets, as if they were already TX completed by a typical driver.
2512 * But we also want to keep skb->sk set because some packet schedulers
2513 * rely on it (sch_fq for example).
2514 */
2515void skb_orphan_partial(struct sk_buff *skb)
2516{
2517	if (skb_is_tcp_pure_ack(skb))
2518		return;
2519
2520	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2521		return;
2522
2523	skb_orphan(skb);
2524}
2525EXPORT_SYMBOL(skb_orphan_partial);
2526
2527/*
2528 * Read buffer destructor automatically called from kfree_skb.
2529 */
2530void sock_rfree(struct sk_buff *skb)
2531{
2532	struct sock *sk = skb->sk;
2533	unsigned int len = skb->truesize;
2534
2535	atomic_sub(len, &sk->sk_rmem_alloc);
2536	sk_mem_uncharge(sk, len);
2537}
2538EXPORT_SYMBOL(sock_rfree);
2539
2540/*
2541 * Buffer destructor for skbs that are not used directly in read or write
2542 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2543 */
2544void sock_efree(struct sk_buff *skb)
2545{
2546	sock_put(skb->sk);
2547}
2548EXPORT_SYMBOL(sock_efree);
2549
2550/* Buffer destructor for prefetch/receive path where reference count may
2551 * not be held, e.g. for listen sockets.
2552 */
2553#ifdef CONFIG_INET
2554void sock_pfree(struct sk_buff *skb)
2555{
2556	if (sk_is_refcounted(skb->sk))
2557		sock_gen_put(skb->sk);
2558}
2559EXPORT_SYMBOL(sock_pfree);
2560#endif /* CONFIG_INET */
2561
2562kuid_t sock_i_uid(struct sock *sk)
2563{
2564	kuid_t uid;
2565
2566	read_lock_bh(&sk->sk_callback_lock);
2567	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2568	read_unlock_bh(&sk->sk_callback_lock);
2569	return uid;
2570}
2571EXPORT_SYMBOL(sock_i_uid);
2572
 
 
 
 
 
 
 
 
 
 
 
2573unsigned long sock_i_ino(struct sock *sk)
2574{
2575	unsigned long ino;
2576
2577	read_lock_bh(&sk->sk_callback_lock);
2578	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2579	read_unlock_bh(&sk->sk_callback_lock);
2580	return ino;
2581}
2582EXPORT_SYMBOL(sock_i_ino);
2583
2584/*
2585 * Allocate a skb from the socket's send buffer.
2586 */
2587struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2588			     gfp_t priority)
2589{
2590	if (force ||
2591	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2592		struct sk_buff *skb = alloc_skb(size, priority);
2593
2594		if (skb) {
2595			skb_set_owner_w(skb, sk);
2596			return skb;
2597		}
2598	}
2599	return NULL;
2600}
2601EXPORT_SYMBOL(sock_wmalloc);
2602
2603static void sock_ofree(struct sk_buff *skb)
2604{
2605	struct sock *sk = skb->sk;
2606
2607	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2608}
2609
2610struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2611			     gfp_t priority)
2612{
2613	struct sk_buff *skb;
2614
2615	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2616	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2617	    READ_ONCE(sysctl_optmem_max))
2618		return NULL;
2619
2620	skb = alloc_skb(size, priority);
2621	if (!skb)
2622		return NULL;
2623
2624	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2625	skb->sk = sk;
2626	skb->destructor = sock_ofree;
2627	return skb;
2628}
2629
2630/*
2631 * Allocate a memory block from the socket's option memory buffer.
2632 */
2633void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2634{
2635	int optmem_max = READ_ONCE(sysctl_optmem_max);
2636
2637	if ((unsigned int)size <= optmem_max &&
2638	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2639		void *mem;
2640		/* First do the add, to avoid the race if kmalloc
2641		 * might sleep.
2642		 */
2643		atomic_add(size, &sk->sk_omem_alloc);
2644		mem = kmalloc(size, priority);
2645		if (mem)
2646			return mem;
2647		atomic_sub(size, &sk->sk_omem_alloc);
2648	}
2649	return NULL;
2650}
2651EXPORT_SYMBOL(sock_kmalloc);
2652
2653/* Free an option memory block. Note, we actually want the inline
2654 * here as this allows gcc to detect the nullify and fold away the
2655 * condition entirely.
2656 */
2657static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2658				  const bool nullify)
2659{
2660	if (WARN_ON_ONCE(!mem))
2661		return;
2662	if (nullify)
2663		kfree_sensitive(mem);
2664	else
2665		kfree(mem);
2666	atomic_sub(size, &sk->sk_omem_alloc);
2667}
2668
2669void sock_kfree_s(struct sock *sk, void *mem, int size)
2670{
2671	__sock_kfree_s(sk, mem, size, false);
2672}
2673EXPORT_SYMBOL(sock_kfree_s);
2674
2675void sock_kzfree_s(struct sock *sk, void *mem, int size)
2676{
2677	__sock_kfree_s(sk, mem, size, true);
2678}
2679EXPORT_SYMBOL(sock_kzfree_s);
2680
2681/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2682   I think, these locks should be removed for datagram sockets.
2683 */
2684static long sock_wait_for_wmem(struct sock *sk, long timeo)
2685{
2686	DEFINE_WAIT(wait);
2687
2688	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2689	for (;;) {
2690		if (!timeo)
2691			break;
2692		if (signal_pending(current))
2693			break;
2694		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2695		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2696		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2697			break;
2698		if (sk->sk_shutdown & SEND_SHUTDOWN)
2699			break;
2700		if (sk->sk_err)
2701			break;
2702		timeo = schedule_timeout(timeo);
2703	}
2704	finish_wait(sk_sleep(sk), &wait);
2705	return timeo;
2706}
2707
2708
2709/*
2710 *	Generic send/receive buffer handlers
2711 */
2712
2713struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2714				     unsigned long data_len, int noblock,
2715				     int *errcode, int max_page_order)
2716{
2717	struct sk_buff *skb;
2718	long timeo;
2719	int err;
2720
2721	timeo = sock_sndtimeo(sk, noblock);
2722	for (;;) {
2723		err = sock_error(sk);
2724		if (err != 0)
2725			goto failure;
2726
2727		err = -EPIPE;
2728		if (sk->sk_shutdown & SEND_SHUTDOWN)
2729			goto failure;
2730
2731		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2732			break;
2733
2734		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2735		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2736		err = -EAGAIN;
2737		if (!timeo)
2738			goto failure;
2739		if (signal_pending(current))
2740			goto interrupted;
2741		timeo = sock_wait_for_wmem(sk, timeo);
2742	}
2743	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2744				   errcode, sk->sk_allocation);
2745	if (skb)
2746		skb_set_owner_w(skb, sk);
2747	return skb;
2748
2749interrupted:
2750	err = sock_intr_errno(timeo);
2751failure:
2752	*errcode = err;
2753	return NULL;
2754}
2755EXPORT_SYMBOL(sock_alloc_send_pskb);
2756
2757int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2758		     struct sockcm_cookie *sockc)
2759{
2760	u32 tsflags;
2761
2762	switch (cmsg->cmsg_type) {
2763	case SO_MARK:
2764		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2765		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2766			return -EPERM;
2767		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2768			return -EINVAL;
2769		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2770		break;
2771	case SO_TIMESTAMPING_OLD:
 
2772		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2773			return -EINVAL;
2774
2775		tsflags = *(u32 *)CMSG_DATA(cmsg);
2776		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2777			return -EINVAL;
2778
2779		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2780		sockc->tsflags |= tsflags;
2781		break;
2782	case SCM_TXTIME:
2783		if (!sock_flag(sk, SOCK_TXTIME))
2784			return -EINVAL;
2785		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2786			return -EINVAL;
2787		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2788		break;
2789	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2790	case SCM_RIGHTS:
2791	case SCM_CREDENTIALS:
2792		break;
2793	default:
2794		return -EINVAL;
2795	}
2796	return 0;
2797}
2798EXPORT_SYMBOL(__sock_cmsg_send);
2799
2800int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2801		   struct sockcm_cookie *sockc)
2802{
2803	struct cmsghdr *cmsg;
2804	int ret;
2805
2806	for_each_cmsghdr(cmsg, msg) {
2807		if (!CMSG_OK(msg, cmsg))
2808			return -EINVAL;
2809		if (cmsg->cmsg_level != SOL_SOCKET)
2810			continue;
2811		ret = __sock_cmsg_send(sk, cmsg, sockc);
2812		if (ret)
2813			return ret;
2814	}
2815	return 0;
2816}
2817EXPORT_SYMBOL(sock_cmsg_send);
2818
2819static void sk_enter_memory_pressure(struct sock *sk)
2820{
2821	if (!sk->sk_prot->enter_memory_pressure)
2822		return;
2823
2824	sk->sk_prot->enter_memory_pressure(sk);
2825}
2826
2827static void sk_leave_memory_pressure(struct sock *sk)
2828{
2829	if (sk->sk_prot->leave_memory_pressure) {
2830		sk->sk_prot->leave_memory_pressure(sk);
 
2831	} else {
2832		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2833
2834		if (memory_pressure && READ_ONCE(*memory_pressure))
2835			WRITE_ONCE(*memory_pressure, 0);
2836	}
2837}
2838
2839DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2840
2841/**
2842 * skb_page_frag_refill - check that a page_frag contains enough room
2843 * @sz: minimum size of the fragment we want to get
2844 * @pfrag: pointer to page_frag
2845 * @gfp: priority for memory allocation
2846 *
2847 * Note: While this allocator tries to use high order pages, there is
2848 * no guarantee that allocations succeed. Therefore, @sz MUST be
2849 * less or equal than PAGE_SIZE.
2850 */
2851bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2852{
2853	if (pfrag->page) {
2854		if (page_ref_count(pfrag->page) == 1) {
2855			pfrag->offset = 0;
2856			return true;
2857		}
2858		if (pfrag->offset + sz <= pfrag->size)
2859			return true;
2860		put_page(pfrag->page);
2861	}
2862
2863	pfrag->offset = 0;
2864	if (SKB_FRAG_PAGE_ORDER &&
2865	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2866		/* Avoid direct reclaim but allow kswapd to wake */
2867		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2868					  __GFP_COMP | __GFP_NOWARN |
2869					  __GFP_NORETRY,
2870					  SKB_FRAG_PAGE_ORDER);
2871		if (likely(pfrag->page)) {
2872			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2873			return true;
2874		}
2875	}
2876	pfrag->page = alloc_page(gfp);
2877	if (likely(pfrag->page)) {
2878		pfrag->size = PAGE_SIZE;
2879		return true;
2880	}
2881	return false;
2882}
2883EXPORT_SYMBOL(skb_page_frag_refill);
2884
2885bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2886{
2887	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2888		return true;
2889
2890	sk_enter_memory_pressure(sk);
2891	sk_stream_moderate_sndbuf(sk);
2892	return false;
2893}
2894EXPORT_SYMBOL(sk_page_frag_refill);
2895
2896void __lock_sock(struct sock *sk)
2897	__releases(&sk->sk_lock.slock)
2898	__acquires(&sk->sk_lock.slock)
2899{
2900	DEFINE_WAIT(wait);
2901
2902	for (;;) {
2903		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2904					TASK_UNINTERRUPTIBLE);
2905		spin_unlock_bh(&sk->sk_lock.slock);
2906		schedule();
2907		spin_lock_bh(&sk->sk_lock.slock);
2908		if (!sock_owned_by_user(sk))
2909			break;
2910	}
2911	finish_wait(&sk->sk_lock.wq, &wait);
2912}
2913
2914void __release_sock(struct sock *sk)
2915	__releases(&sk->sk_lock.slock)
2916	__acquires(&sk->sk_lock.slock)
2917{
2918	struct sk_buff *skb, *next;
2919
2920	while ((skb = sk->sk_backlog.head) != NULL) {
2921		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2922
2923		spin_unlock_bh(&sk->sk_lock.slock);
2924
2925		do {
2926			next = skb->next;
2927			prefetch(next);
2928			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2929			skb_mark_not_on_list(skb);
2930			sk_backlog_rcv(sk, skb);
2931
2932			cond_resched();
2933
2934			skb = next;
2935		} while (skb != NULL);
2936
2937		spin_lock_bh(&sk->sk_lock.slock);
2938	}
2939
2940	/*
2941	 * Doing the zeroing here guarantee we can not loop forever
2942	 * while a wild producer attempts to flood us.
2943	 */
2944	sk->sk_backlog.len = 0;
2945}
2946
2947void __sk_flush_backlog(struct sock *sk)
2948{
2949	spin_lock_bh(&sk->sk_lock.slock);
2950	__release_sock(sk);
 
 
 
 
 
2951	spin_unlock_bh(&sk->sk_lock.slock);
2952}
2953EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2954
2955/**
2956 * sk_wait_data - wait for data to arrive at sk_receive_queue
2957 * @sk:    sock to wait on
2958 * @timeo: for how long
2959 * @skb:   last skb seen on sk_receive_queue
2960 *
2961 * Now socket state including sk->sk_err is changed only under lock,
2962 * hence we may omit checks after joining wait queue.
2963 * We check receive queue before schedule() only as optimization;
2964 * it is very likely that release_sock() added new data.
2965 */
2966int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2967{
2968	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2969	int rc;
2970
2971	add_wait_queue(sk_sleep(sk), &wait);
2972	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2973	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2974	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2975	remove_wait_queue(sk_sleep(sk), &wait);
2976	return rc;
2977}
2978EXPORT_SYMBOL(sk_wait_data);
2979
2980/**
2981 *	__sk_mem_raise_allocated - increase memory_allocated
2982 *	@sk: socket
2983 *	@size: memory size to allocate
2984 *	@amt: pages to allocate
2985 *	@kind: allocation type
2986 *
2987 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
 
 
 
 
 
 
2988 */
2989int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2990{
2991	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2992	struct proto *prot = sk->sk_prot;
2993	bool charged = true;
2994	long allocated;
2995
2996	sk_memory_allocated_add(sk, amt);
2997	allocated = sk_memory_allocated(sk);
2998	if (memcg_charge &&
2999	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3000						gfp_memcg_charge())))
3001		goto suppress_allocation;
 
 
3002
3003	/* Under limit. */
3004	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3005		sk_leave_memory_pressure(sk);
3006		return 1;
3007	}
3008
3009	/* Under pressure. */
3010	if (allocated > sk_prot_mem_limits(sk, 1))
3011		sk_enter_memory_pressure(sk);
3012
3013	/* Over hard limit. */
3014	if (allocated > sk_prot_mem_limits(sk, 2))
3015		goto suppress_allocation;
3016
3017	/* guarantee minimum buffer size under pressure */
 
 
 
 
 
 
 
3018	if (kind == SK_MEM_RECV) {
3019		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3020			return 1;
3021
3022	} else { /* SK_MEM_SEND */
3023		int wmem0 = sk_get_wmem0(sk, prot);
3024
3025		if (sk->sk_type == SOCK_STREAM) {
3026			if (sk->sk_wmem_queued < wmem0)
3027				return 1;
3028		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3029				return 1;
3030		}
3031	}
3032
3033	if (sk_has_memory_pressure(sk)) {
3034		u64 alloc;
3035
3036		if (!sk_under_memory_pressure(sk))
 
 
 
 
3037			return 1;
 
 
 
 
 
3038		alloc = sk_sockets_allocated_read_positive(sk);
3039		if (sk_prot_mem_limits(sk, 2) > alloc *
3040		    sk_mem_pages(sk->sk_wmem_queued +
3041				 atomic_read(&sk->sk_rmem_alloc) +
3042				 sk->sk_forward_alloc))
3043			return 1;
3044	}
3045
3046suppress_allocation:
3047
3048	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3049		sk_stream_moderate_sndbuf(sk);
3050
3051		/* Fail only if socket is _under_ its sndbuf.
3052		 * In this case we cannot block, so that we have to fail.
3053		 */
3054		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3055			/* Force charge with __GFP_NOFAIL */
3056			if (memcg_charge && !charged) {
3057				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3058					gfp_memcg_charge() | __GFP_NOFAIL);
3059			}
3060			return 1;
3061		}
3062	}
3063
3064	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3065		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3066
3067	sk_memory_allocated_sub(sk, amt);
3068
3069	if (memcg_charge && charged)
3070		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3071
3072	return 0;
3073}
3074
3075/**
3076 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3077 *	@sk: socket
3078 *	@size: memory size to allocate
3079 *	@kind: allocation type
3080 *
3081 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3082 *	rmem allocation. This function assumes that protocols which have
3083 *	memory_pressure use sk_wmem_queued as write buffer accounting.
3084 */
3085int __sk_mem_schedule(struct sock *sk, int size, int kind)
3086{
3087	int ret, amt = sk_mem_pages(size);
3088
3089	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3090	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3091	if (!ret)
3092		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3093	return ret;
3094}
3095EXPORT_SYMBOL(__sk_mem_schedule);
3096
3097/**
3098 *	__sk_mem_reduce_allocated - reclaim memory_allocated
3099 *	@sk: socket
3100 *	@amount: number of quanta
3101 *
3102 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3103 */
3104void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3105{
3106	sk_memory_allocated_sub(sk, amount);
3107
3108	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3109		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3110
3111	if (sk_under_memory_pressure(sk) &&
3112	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3113		sk_leave_memory_pressure(sk);
3114}
3115
3116/**
3117 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3118 *	@sk: socket
3119 *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3120 */
3121void __sk_mem_reclaim(struct sock *sk, int amount)
3122{
3123	amount >>= PAGE_SHIFT;
3124	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3125	__sk_mem_reduce_allocated(sk, amount);
3126}
3127EXPORT_SYMBOL(__sk_mem_reclaim);
3128
3129int sk_set_peek_off(struct sock *sk, int val)
3130{
3131	sk->sk_peek_off = val;
3132	return 0;
3133}
3134EXPORT_SYMBOL_GPL(sk_set_peek_off);
3135
3136/*
3137 * Set of default routines for initialising struct proto_ops when
3138 * the protocol does not support a particular function. In certain
3139 * cases where it makes no sense for a protocol to have a "do nothing"
3140 * function, some default processing is provided.
3141 */
3142
3143int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3144{
3145	return -EOPNOTSUPP;
3146}
3147EXPORT_SYMBOL(sock_no_bind);
3148
3149int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3150		    int len, int flags)
3151{
3152	return -EOPNOTSUPP;
3153}
3154EXPORT_SYMBOL(sock_no_connect);
3155
3156int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3157{
3158	return -EOPNOTSUPP;
3159}
3160EXPORT_SYMBOL(sock_no_socketpair);
3161
3162int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3163		   bool kern)
3164{
3165	return -EOPNOTSUPP;
3166}
3167EXPORT_SYMBOL(sock_no_accept);
3168
3169int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3170		    int peer)
3171{
3172	return -EOPNOTSUPP;
3173}
3174EXPORT_SYMBOL(sock_no_getname);
3175
3176int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3177{
3178	return -EOPNOTSUPP;
3179}
3180EXPORT_SYMBOL(sock_no_ioctl);
3181
3182int sock_no_listen(struct socket *sock, int backlog)
3183{
3184	return -EOPNOTSUPP;
3185}
3186EXPORT_SYMBOL(sock_no_listen);
3187
3188int sock_no_shutdown(struct socket *sock, int how)
3189{
3190	return -EOPNOTSUPP;
3191}
3192EXPORT_SYMBOL(sock_no_shutdown);
3193
3194int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3195{
3196	return -EOPNOTSUPP;
3197}
3198EXPORT_SYMBOL(sock_no_sendmsg);
3199
3200int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3201{
3202	return -EOPNOTSUPP;
3203}
3204EXPORT_SYMBOL(sock_no_sendmsg_locked);
3205
3206int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3207		    int flags)
3208{
3209	return -EOPNOTSUPP;
3210}
3211EXPORT_SYMBOL(sock_no_recvmsg);
3212
3213int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3214{
3215	/* Mirror missing mmap method error code */
3216	return -ENODEV;
3217}
3218EXPORT_SYMBOL(sock_no_mmap);
3219
3220/*
3221 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3222 * various sock-based usage counts.
3223 */
3224void __receive_sock(struct file *file)
3225{
3226	struct socket *sock;
3227
3228	sock = sock_from_file(file);
3229	if (sock) {
3230		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3231		sock_update_classid(&sock->sk->sk_cgrp_data);
3232	}
3233}
3234
3235ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3236{
3237	ssize_t res;
3238	struct msghdr msg = {.msg_flags = flags};
3239	struct kvec iov;
3240	char *kaddr = kmap(page);
3241	iov.iov_base = kaddr + offset;
3242	iov.iov_len = size;
3243	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3244	kunmap(page);
3245	return res;
3246}
3247EXPORT_SYMBOL(sock_no_sendpage);
3248
3249ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3250				int offset, size_t size, int flags)
3251{
3252	ssize_t res;
3253	struct msghdr msg = {.msg_flags = flags};
3254	struct kvec iov;
3255	char *kaddr = kmap(page);
3256
3257	iov.iov_base = kaddr + offset;
3258	iov.iov_len = size;
3259	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3260	kunmap(page);
3261	return res;
3262}
3263EXPORT_SYMBOL(sock_no_sendpage_locked);
3264
3265/*
3266 *	Default Socket Callbacks
3267 */
3268
3269static void sock_def_wakeup(struct sock *sk)
3270{
3271	struct socket_wq *wq;
3272
3273	rcu_read_lock();
3274	wq = rcu_dereference(sk->sk_wq);
3275	if (skwq_has_sleeper(wq))
3276		wake_up_interruptible_all(&wq->wait);
3277	rcu_read_unlock();
3278}
3279
3280static void sock_def_error_report(struct sock *sk)
3281{
3282	struct socket_wq *wq;
3283
3284	rcu_read_lock();
3285	wq = rcu_dereference(sk->sk_wq);
3286	if (skwq_has_sleeper(wq))
3287		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3288	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3289	rcu_read_unlock();
3290}
3291
3292void sock_def_readable(struct sock *sk)
3293{
3294	struct socket_wq *wq;
3295
 
 
3296	rcu_read_lock();
3297	wq = rcu_dereference(sk->sk_wq);
3298	if (skwq_has_sleeper(wq))
3299		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3300						EPOLLRDNORM | EPOLLRDBAND);
3301	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3302	rcu_read_unlock();
3303}
3304
3305static void sock_def_write_space(struct sock *sk)
3306{
3307	struct socket_wq *wq;
3308
3309	rcu_read_lock();
3310
3311	/* Do not wake up a writer until he can make "significant"
3312	 * progress.  --DaveM
3313	 */
3314	if (sock_writeable(sk)) {
3315		wq = rcu_dereference(sk->sk_wq);
3316		if (skwq_has_sleeper(wq))
3317			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3318						EPOLLWRNORM | EPOLLWRBAND);
3319
3320		/* Should agree with poll, otherwise some programs break */
3321		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3322	}
3323
3324	rcu_read_unlock();
3325}
3326
3327/* An optimised version of sock_def_write_space(), should only be called
3328 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3329 * ->sk_wmem_alloc.
3330 */
3331static void sock_def_write_space_wfree(struct sock *sk)
3332{
3333	/* Do not wake up a writer until he can make "significant"
3334	 * progress.  --DaveM
3335	 */
3336	if (sock_writeable(sk)) {
3337		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3338
3339		/* rely on refcount_sub from sock_wfree() */
3340		smp_mb__after_atomic();
3341		if (wq && waitqueue_active(&wq->wait))
3342			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3343						EPOLLWRNORM | EPOLLWRBAND);
3344
3345		/* Should agree with poll, otherwise some programs break */
3346		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3347	}
3348}
3349
3350static void sock_def_destruct(struct sock *sk)
3351{
3352}
3353
3354void sk_send_sigurg(struct sock *sk)
3355{
3356	if (sk->sk_socket && sk->sk_socket->file)
3357		if (send_sigurg(&sk->sk_socket->file->f_owner))
3358			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3359}
3360EXPORT_SYMBOL(sk_send_sigurg);
3361
3362void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3363		    unsigned long expires)
3364{
3365	if (!mod_timer(timer, expires))
3366		sock_hold(sk);
3367}
3368EXPORT_SYMBOL(sk_reset_timer);
3369
3370void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3371{
3372	if (del_timer(timer))
3373		__sock_put(sk);
3374}
3375EXPORT_SYMBOL(sk_stop_timer);
3376
3377void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3378{
3379	if (del_timer_sync(timer))
3380		__sock_put(sk);
3381}
3382EXPORT_SYMBOL(sk_stop_timer_sync);
3383
3384void sock_init_data(struct socket *sock, struct sock *sk)
3385{
3386	sk_init_common(sk);
3387	sk->sk_send_head	=	NULL;
3388
3389	timer_setup(&sk->sk_timer, NULL, 0);
3390
3391	sk->sk_allocation	=	GFP_KERNEL;
3392	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3393	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3394	sk->sk_state		=	TCP_CLOSE;
3395	sk->sk_use_task_frag	=	true;
3396	sk_set_socket(sk, sock);
3397
3398	sock_set_flag(sk, SOCK_ZAPPED);
3399
3400	if (sock) {
3401		sk->sk_type	=	sock->type;
3402		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3403		sock->sk	=	sk;
3404		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3405	} else {
3406		RCU_INIT_POINTER(sk->sk_wq, NULL);
3407		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3408	}
 
3409
3410	rwlock_init(&sk->sk_callback_lock);
3411	if (sk->sk_kern_sock)
3412		lockdep_set_class_and_name(
3413			&sk->sk_callback_lock,
3414			af_kern_callback_keys + sk->sk_family,
3415			af_family_kern_clock_key_strings[sk->sk_family]);
3416	else
3417		lockdep_set_class_and_name(
3418			&sk->sk_callback_lock,
3419			af_callback_keys + sk->sk_family,
3420			af_family_clock_key_strings[sk->sk_family]);
3421
3422	sk->sk_state_change	=	sock_def_wakeup;
3423	sk->sk_data_ready	=	sock_def_readable;
3424	sk->sk_write_space	=	sock_def_write_space;
3425	sk->sk_error_report	=	sock_def_error_report;
3426	sk->sk_destruct		=	sock_def_destruct;
3427
3428	sk->sk_frag.page	=	NULL;
3429	sk->sk_frag.offset	=	0;
3430	sk->sk_peek_off		=	-1;
3431
3432	sk->sk_peer_pid 	=	NULL;
3433	sk->sk_peer_cred	=	NULL;
3434	spin_lock_init(&sk->sk_peer_lock);
3435
3436	sk->sk_write_pending	=	0;
3437	sk->sk_rcvlowat		=	1;
3438	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3439	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3440
3441	sk->sk_stamp = SK_DEFAULT_STAMP;
3442#if BITS_PER_LONG==32
3443	seqlock_init(&sk->sk_stamp_seq);
3444#endif
3445	atomic_set(&sk->sk_zckey, 0);
3446
3447#ifdef CONFIG_NET_RX_BUSY_POLL
3448	sk->sk_napi_id		=	0;
3449	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3450#endif
3451
3452	sk->sk_max_pacing_rate = ~0UL;
3453	sk->sk_pacing_rate = ~0UL;
3454	WRITE_ONCE(sk->sk_pacing_shift, 10);
3455	sk->sk_incoming_cpu = -1;
3456
3457	sk_rx_queue_clear(sk);
3458	/*
3459	 * Before updating sk_refcnt, we must commit prior changes to memory
3460	 * (Documentation/RCU/rculist_nulls.rst for details)
3461	 */
3462	smp_wmb();
3463	refcount_set(&sk->sk_refcnt, 1);
3464	atomic_set(&sk->sk_drops, 0);
3465}
 
 
 
 
 
 
 
 
 
 
3466EXPORT_SYMBOL(sock_init_data);
3467
3468void lock_sock_nested(struct sock *sk, int subclass)
3469{
3470	/* The sk_lock has mutex_lock() semantics here. */
3471	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3472
3473	might_sleep();
3474	spin_lock_bh(&sk->sk_lock.slock);
3475	if (sock_owned_by_user_nocheck(sk))
3476		__lock_sock(sk);
3477	sk->sk_lock.owned = 1;
3478	spin_unlock_bh(&sk->sk_lock.slock);
3479}
3480EXPORT_SYMBOL(lock_sock_nested);
3481
3482void release_sock(struct sock *sk)
3483{
3484	spin_lock_bh(&sk->sk_lock.slock);
3485	if (sk->sk_backlog.tail)
3486		__release_sock(sk);
3487
3488	/* Warning : release_cb() might need to release sk ownership,
3489	 * ie call sock_release_ownership(sk) before us.
3490	 */
3491	if (sk->sk_prot->release_cb)
3492		sk->sk_prot->release_cb(sk);
 
3493
3494	sock_release_ownership(sk);
3495	if (waitqueue_active(&sk->sk_lock.wq))
3496		wake_up(&sk->sk_lock.wq);
3497	spin_unlock_bh(&sk->sk_lock.slock);
3498}
3499EXPORT_SYMBOL(release_sock);
3500
3501bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3502{
3503	might_sleep();
3504	spin_lock_bh(&sk->sk_lock.slock);
3505
3506	if (!sock_owned_by_user_nocheck(sk)) {
3507		/*
3508		 * Fast path return with bottom halves disabled and
3509		 * sock::sk_lock.slock held.
3510		 *
3511		 * The 'mutex' is not contended and holding
3512		 * sock::sk_lock.slock prevents all other lockers to
3513		 * proceed so the corresponding unlock_sock_fast() can
3514		 * avoid the slow path of release_sock() completely and
3515		 * just release slock.
3516		 *
3517		 * From a semantical POV this is equivalent to 'acquiring'
3518		 * the 'mutex', hence the corresponding lockdep
3519		 * mutex_release() has to happen in the fast path of
3520		 * unlock_sock_fast().
3521		 */
3522		return false;
3523	}
3524
3525	__lock_sock(sk);
3526	sk->sk_lock.owned = 1;
3527	__acquire(&sk->sk_lock.slock);
3528	spin_unlock_bh(&sk->sk_lock.slock);
3529	return true;
3530}
3531EXPORT_SYMBOL(__lock_sock_fast);
3532
3533int sock_gettstamp(struct socket *sock, void __user *userstamp,
3534		   bool timeval, bool time32)
3535{
3536	struct sock *sk = sock->sk;
3537	struct timespec64 ts;
3538
3539	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3540	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3541	if (ts.tv_sec == -1)
3542		return -ENOENT;
3543	if (ts.tv_sec == 0) {
3544		ktime_t kt = ktime_get_real();
3545		sock_write_timestamp(sk, kt);
3546		ts = ktime_to_timespec64(kt);
3547	}
3548
3549	if (timeval)
3550		ts.tv_nsec /= 1000;
3551
3552#ifdef CONFIG_COMPAT_32BIT_TIME
3553	if (time32)
3554		return put_old_timespec32(&ts, userstamp);
3555#endif
3556#ifdef CONFIG_SPARC64
3557	/* beware of padding in sparc64 timeval */
3558	if (timeval && !in_compat_syscall()) {
3559		struct __kernel_old_timeval __user tv = {
3560			.tv_sec = ts.tv_sec,
3561			.tv_usec = ts.tv_nsec,
3562		};
3563		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3564			return -EFAULT;
3565		return 0;
3566	}
3567#endif
3568	return put_timespec64(&ts, userstamp);
3569}
3570EXPORT_SYMBOL(sock_gettstamp);
3571
3572void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3573{
3574	if (!sock_flag(sk, flag)) {
3575		unsigned long previous_flags = sk->sk_flags;
3576
3577		sock_set_flag(sk, flag);
3578		/*
3579		 * we just set one of the two flags which require net
3580		 * time stamping, but time stamping might have been on
3581		 * already because of the other one
3582		 */
3583		if (sock_needs_netstamp(sk) &&
3584		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3585			net_enable_timestamp();
3586	}
3587}
3588
3589int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3590		       int level, int type)
3591{
3592	struct sock_exterr_skb *serr;
3593	struct sk_buff *skb;
3594	int copied, err;
3595
3596	err = -EAGAIN;
3597	skb = sock_dequeue_err_skb(sk);
3598	if (skb == NULL)
3599		goto out;
3600
3601	copied = skb->len;
3602	if (copied > len) {
3603		msg->msg_flags |= MSG_TRUNC;
3604		copied = len;
3605	}
3606	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3607	if (err)
3608		goto out_free_skb;
3609
3610	sock_recv_timestamp(msg, sk, skb);
3611
3612	serr = SKB_EXT_ERR(skb);
3613	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3614
3615	msg->msg_flags |= MSG_ERRQUEUE;
3616	err = copied;
3617
3618out_free_skb:
3619	kfree_skb(skb);
3620out:
3621	return err;
3622}
3623EXPORT_SYMBOL(sock_recv_errqueue);
3624
3625/*
3626 *	Get a socket option on an socket.
3627 *
3628 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3629 *	asynchronous errors should be reported by getsockopt. We assume
3630 *	this means if you specify SO_ERROR (otherwise whats the point of it).
3631 */
3632int sock_common_getsockopt(struct socket *sock, int level, int optname,
3633			   char __user *optval, int __user *optlen)
3634{
3635	struct sock *sk = sock->sk;
3636
3637	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3638	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3639}
3640EXPORT_SYMBOL(sock_common_getsockopt);
3641
3642int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3643			int flags)
3644{
3645	struct sock *sk = sock->sk;
3646	int addr_len = 0;
3647	int err;
3648
3649	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3650	if (err >= 0)
3651		msg->msg_namelen = addr_len;
3652	return err;
3653}
3654EXPORT_SYMBOL(sock_common_recvmsg);
3655
3656/*
3657 *	Set socket options on an inet socket.
3658 */
3659int sock_common_setsockopt(struct socket *sock, int level, int optname,
3660			   sockptr_t optval, unsigned int optlen)
3661{
3662	struct sock *sk = sock->sk;
3663
3664	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3665	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3666}
3667EXPORT_SYMBOL(sock_common_setsockopt);
3668
3669void sk_common_release(struct sock *sk)
3670{
3671	if (sk->sk_prot->destroy)
3672		sk->sk_prot->destroy(sk);
3673
3674	/*
3675	 * Observation: when sk_common_release is called, processes have
3676	 * no access to socket. But net still has.
3677	 * Step one, detach it from networking:
3678	 *
3679	 * A. Remove from hash tables.
3680	 */
3681
3682	sk->sk_prot->unhash(sk);
3683
3684	/*
3685	 * In this point socket cannot receive new packets, but it is possible
3686	 * that some packets are in flight because some CPU runs receiver and
3687	 * did hash table lookup before we unhashed socket. They will achieve
3688	 * receive queue and will be purged by socket destructor.
3689	 *
3690	 * Also we still have packets pending on receive queue and probably,
3691	 * our own packets waiting in device queues. sock_destroy will drain
3692	 * receive queue, but transmitted packets will delay socket destruction
3693	 * until the last reference will be released.
3694	 */
3695
3696	sock_orphan(sk);
3697
3698	xfrm_sk_free_policy(sk);
3699
3700	sk_refcnt_debug_release(sk);
3701
3702	sock_put(sk);
3703}
3704EXPORT_SYMBOL(sk_common_release);
3705
3706void sk_get_meminfo(const struct sock *sk, u32 *mem)
3707{
3708	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3709
3710	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3711	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3712	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3713	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3714	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3715	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3716	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3717	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3718	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3719}
3720
3721#ifdef CONFIG_PROC_FS
3722static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3723
3724int sock_prot_inuse_get(struct net *net, struct proto *prot)
3725{
3726	int cpu, idx = prot->inuse_idx;
3727	int res = 0;
3728
3729	for_each_possible_cpu(cpu)
3730		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3731
3732	return res >= 0 ? res : 0;
3733}
3734EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3735
3736int sock_inuse_get(struct net *net)
3737{
3738	int cpu, res = 0;
3739
3740	for_each_possible_cpu(cpu)
3741		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3742
3743	return res;
3744}
3745
3746EXPORT_SYMBOL_GPL(sock_inuse_get);
3747
3748static int __net_init sock_inuse_init_net(struct net *net)
3749{
3750	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3751	if (net->core.prot_inuse == NULL)
3752		return -ENOMEM;
3753	return 0;
3754}
3755
3756static void __net_exit sock_inuse_exit_net(struct net *net)
3757{
3758	free_percpu(net->core.prot_inuse);
3759}
3760
3761static struct pernet_operations net_inuse_ops = {
3762	.init = sock_inuse_init_net,
3763	.exit = sock_inuse_exit_net,
3764};
3765
3766static __init int net_inuse_init(void)
3767{
3768	if (register_pernet_subsys(&net_inuse_ops))
3769		panic("Cannot initialize net inuse counters");
3770
3771	return 0;
3772}
3773
3774core_initcall(net_inuse_init);
3775
3776static int assign_proto_idx(struct proto *prot)
3777{
3778	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3779
3780	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3781		pr_err("PROTO_INUSE_NR exhausted\n");
3782		return -ENOSPC;
3783	}
3784
3785	set_bit(prot->inuse_idx, proto_inuse_idx);
3786	return 0;
3787}
3788
3789static void release_proto_idx(struct proto *prot)
3790{
3791	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3792		clear_bit(prot->inuse_idx, proto_inuse_idx);
3793}
3794#else
3795static inline int assign_proto_idx(struct proto *prot)
3796{
3797	return 0;
3798}
3799
3800static inline void release_proto_idx(struct proto *prot)
3801{
3802}
3803
3804#endif
3805
3806static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3807{
3808	if (!twsk_prot)
3809		return;
3810	kfree(twsk_prot->twsk_slab_name);
3811	twsk_prot->twsk_slab_name = NULL;
3812	kmem_cache_destroy(twsk_prot->twsk_slab);
3813	twsk_prot->twsk_slab = NULL;
3814}
3815
3816static int tw_prot_init(const struct proto *prot)
3817{
3818	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3819
3820	if (!twsk_prot)
3821		return 0;
3822
3823	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3824					      prot->name);
3825	if (!twsk_prot->twsk_slab_name)
3826		return -ENOMEM;
3827
3828	twsk_prot->twsk_slab =
3829		kmem_cache_create(twsk_prot->twsk_slab_name,
3830				  twsk_prot->twsk_obj_size, 0,
3831				  SLAB_ACCOUNT | prot->slab_flags,
3832				  NULL);
3833	if (!twsk_prot->twsk_slab) {
3834		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3835			prot->name);
3836		return -ENOMEM;
3837	}
3838
3839	return 0;
3840}
3841
3842static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3843{
3844	if (!rsk_prot)
3845		return;
3846	kfree(rsk_prot->slab_name);
3847	rsk_prot->slab_name = NULL;
3848	kmem_cache_destroy(rsk_prot->slab);
3849	rsk_prot->slab = NULL;
3850}
3851
3852static int req_prot_init(const struct proto *prot)
3853{
3854	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3855
3856	if (!rsk_prot)
3857		return 0;
3858
3859	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3860					prot->name);
3861	if (!rsk_prot->slab_name)
3862		return -ENOMEM;
3863
3864	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3865					   rsk_prot->obj_size, 0,
3866					   SLAB_ACCOUNT | prot->slab_flags,
3867					   NULL);
3868
3869	if (!rsk_prot->slab) {
3870		pr_crit("%s: Can't create request sock SLAB cache!\n",
3871			prot->name);
3872		return -ENOMEM;
3873	}
3874	return 0;
3875}
3876
3877int proto_register(struct proto *prot, int alloc_slab)
3878{
3879	int ret = -ENOBUFS;
3880
3881	if (prot->memory_allocated && !prot->sysctl_mem) {
3882		pr_err("%s: missing sysctl_mem\n", prot->name);
3883		return -EINVAL;
3884	}
3885	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3886		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3887		return -EINVAL;
3888	}
3889	if (alloc_slab) {
3890		prot->slab = kmem_cache_create_usercopy(prot->name,
3891					prot->obj_size, 0,
3892					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3893					prot->slab_flags,
3894					prot->useroffset, prot->usersize,
3895					NULL);
3896
3897		if (prot->slab == NULL) {
3898			pr_crit("%s: Can't create sock SLAB cache!\n",
3899				prot->name);
3900			goto out;
3901		}
3902
3903		if (req_prot_init(prot))
3904			goto out_free_request_sock_slab;
3905
3906		if (tw_prot_init(prot))
3907			goto out_free_timewait_sock_slab;
3908	}
3909
3910	mutex_lock(&proto_list_mutex);
3911	ret = assign_proto_idx(prot);
3912	if (ret) {
3913		mutex_unlock(&proto_list_mutex);
3914		goto out_free_timewait_sock_slab;
3915	}
3916	list_add(&prot->node, &proto_list);
3917	mutex_unlock(&proto_list_mutex);
3918	return ret;
3919
3920out_free_timewait_sock_slab:
3921	if (alloc_slab)
3922		tw_prot_cleanup(prot->twsk_prot);
3923out_free_request_sock_slab:
3924	if (alloc_slab) {
3925		req_prot_cleanup(prot->rsk_prot);
3926
3927		kmem_cache_destroy(prot->slab);
3928		prot->slab = NULL;
3929	}
3930out:
3931	return ret;
3932}
3933EXPORT_SYMBOL(proto_register);
3934
3935void proto_unregister(struct proto *prot)
3936{
3937	mutex_lock(&proto_list_mutex);
3938	release_proto_idx(prot);
3939	list_del(&prot->node);
3940	mutex_unlock(&proto_list_mutex);
3941
3942	kmem_cache_destroy(prot->slab);
3943	prot->slab = NULL;
3944
3945	req_prot_cleanup(prot->rsk_prot);
3946	tw_prot_cleanup(prot->twsk_prot);
3947}
3948EXPORT_SYMBOL(proto_unregister);
3949
3950int sock_load_diag_module(int family, int protocol)
3951{
3952	if (!protocol) {
3953		if (!sock_is_registered(family))
3954			return -ENOENT;
3955
3956		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3957				      NETLINK_SOCK_DIAG, family);
3958	}
3959
3960#ifdef CONFIG_INET
3961	if (family == AF_INET &&
3962	    protocol != IPPROTO_RAW &&
3963	    protocol < MAX_INET_PROTOS &&
3964	    !rcu_access_pointer(inet_protos[protocol]))
3965		return -ENOENT;
3966#endif
3967
3968	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3969			      NETLINK_SOCK_DIAG, family, protocol);
3970}
3971EXPORT_SYMBOL(sock_load_diag_module);
3972
3973#ifdef CONFIG_PROC_FS
3974static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3975	__acquires(proto_list_mutex)
3976{
3977	mutex_lock(&proto_list_mutex);
3978	return seq_list_start_head(&proto_list, *pos);
3979}
3980
3981static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3982{
3983	return seq_list_next(v, &proto_list, pos);
3984}
3985
3986static void proto_seq_stop(struct seq_file *seq, void *v)
3987	__releases(proto_list_mutex)
3988{
3989	mutex_unlock(&proto_list_mutex);
3990}
3991
3992static char proto_method_implemented(const void *method)
3993{
3994	return method == NULL ? 'n' : 'y';
3995}
3996static long sock_prot_memory_allocated(struct proto *proto)
3997{
3998	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3999}
4000
4001static const char *sock_prot_memory_pressure(struct proto *proto)
4002{
4003	return proto->memory_pressure != NULL ?
4004	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4005}
4006
4007static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4008{
4009
4010	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4011			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4012		   proto->name,
4013		   proto->obj_size,
4014		   sock_prot_inuse_get(seq_file_net(seq), proto),
4015		   sock_prot_memory_allocated(proto),
4016		   sock_prot_memory_pressure(proto),
4017		   proto->max_header,
4018		   proto->slab == NULL ? "no" : "yes",
4019		   module_name(proto->owner),
4020		   proto_method_implemented(proto->close),
4021		   proto_method_implemented(proto->connect),
4022		   proto_method_implemented(proto->disconnect),
4023		   proto_method_implemented(proto->accept),
4024		   proto_method_implemented(proto->ioctl),
4025		   proto_method_implemented(proto->init),
4026		   proto_method_implemented(proto->destroy),
4027		   proto_method_implemented(proto->shutdown),
4028		   proto_method_implemented(proto->setsockopt),
4029		   proto_method_implemented(proto->getsockopt),
4030		   proto_method_implemented(proto->sendmsg),
4031		   proto_method_implemented(proto->recvmsg),
4032		   proto_method_implemented(proto->sendpage),
4033		   proto_method_implemented(proto->bind),
4034		   proto_method_implemented(proto->backlog_rcv),
4035		   proto_method_implemented(proto->hash),
4036		   proto_method_implemented(proto->unhash),
4037		   proto_method_implemented(proto->get_port),
4038		   proto_method_implemented(proto->enter_memory_pressure));
4039}
4040
4041static int proto_seq_show(struct seq_file *seq, void *v)
4042{
4043	if (v == &proto_list)
4044		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4045			   "protocol",
4046			   "size",
4047			   "sockets",
4048			   "memory",
4049			   "press",
4050			   "maxhdr",
4051			   "slab",
4052			   "module",
4053			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4054	else
4055		proto_seq_printf(seq, list_entry(v, struct proto, node));
4056	return 0;
4057}
4058
4059static const struct seq_operations proto_seq_ops = {
4060	.start  = proto_seq_start,
4061	.next   = proto_seq_next,
4062	.stop   = proto_seq_stop,
4063	.show   = proto_seq_show,
4064};
4065
4066static __net_init int proto_init_net(struct net *net)
4067{
4068	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4069			sizeof(struct seq_net_private)))
4070		return -ENOMEM;
4071
4072	return 0;
4073}
4074
4075static __net_exit void proto_exit_net(struct net *net)
4076{
4077	remove_proc_entry("protocols", net->proc_net);
4078}
4079
4080
4081static __net_initdata struct pernet_operations proto_net_ops = {
4082	.init = proto_init_net,
4083	.exit = proto_exit_net,
4084};
4085
4086static int __init proto_init(void)
4087{
4088	return register_pernet_subsys(&proto_net_ops);
4089}
4090
4091subsys_initcall(proto_init);
4092
4093#endif /* PROC_FS */
4094
4095#ifdef CONFIG_NET_RX_BUSY_POLL
4096bool sk_busy_loop_end(void *p, unsigned long start_time)
4097{
4098	struct sock *sk = p;
4099
4100	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4101	       sk_busy_loop_timeout(sk, start_time);
 
 
 
 
 
 
4102}
4103EXPORT_SYMBOL(sk_busy_loop_end);
4104#endif /* CONFIG_NET_RX_BUSY_POLL */
4105
4106int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4107{
4108	if (!sk->sk_prot->bind_add)
4109		return -EOPNOTSUPP;
4110	return sk->sk_prot->bind_add(sk, addr, addr_len);
4111}
4112EXPORT_SYMBOL(sock_bind_add);