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v5.14.15
   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
 
 
 144static DEFINE_MUTEX(proto_list_mutex);
 145static LIST_HEAD(proto_list);
 146
 147static void sock_inuse_add(struct net *net, int val);
 
 148
 149/**
 150 * sk_ns_capable - General socket capability test
 151 * @sk: Socket to use a capability on or through
 152 * @user_ns: The user namespace of the capability to use
 153 * @cap: The capability to use
 154 *
 155 * Test to see if the opener of the socket had when the socket was
 156 * created and the current process has the capability @cap in the user
 157 * namespace @user_ns.
 158 */
 159bool sk_ns_capable(const struct sock *sk,
 160		   struct user_namespace *user_ns, int cap)
 161{
 162	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
 163		ns_capable(user_ns, cap);
 164}
 165EXPORT_SYMBOL(sk_ns_capable);
 166
 167/**
 168 * sk_capable - Socket global capability test
 169 * @sk: Socket to use a capability on or through
 170 * @cap: The global capability to use
 171 *
 172 * Test to see if the opener of the socket had when the socket was
 173 * created and the current process has the capability @cap in all user
 174 * namespaces.
 175 */
 176bool sk_capable(const struct sock *sk, int cap)
 177{
 178	return sk_ns_capable(sk, &init_user_ns, cap);
 179}
 180EXPORT_SYMBOL(sk_capable);
 181
 182/**
 183 * sk_net_capable - Network namespace socket capability test
 184 * @sk: Socket to use a capability on or through
 185 * @cap: The capability to use
 186 *
 187 * Test to see if the opener of the socket had when the socket was created
 188 * and the current process has the capability @cap over the network namespace
 189 * the socket is a member of.
 190 */
 191bool sk_net_capable(const struct sock *sk, int cap)
 192{
 193	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
 194}
 195EXPORT_SYMBOL(sk_net_capable);
 196
 197/*
 198 * Each address family might have different locking rules, so we have
 199 * one slock key per address family and separate keys for internal and
 200 * userspace sockets.
 201 */
 202static struct lock_class_key af_family_keys[AF_MAX];
 203static struct lock_class_key af_family_kern_keys[AF_MAX];
 204static struct lock_class_key af_family_slock_keys[AF_MAX];
 205static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
 206
 207/*
 208 * Make lock validator output more readable. (we pre-construct these
 209 * strings build-time, so that runtime initialization of socket
 210 * locks is fast):
 211 */
 212
 213#define _sock_locks(x)						  \
 214  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
 215  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
 216  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
 217  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
 218  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
 219  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
 220  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
 221  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
 222  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
 223  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
 224  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
 225  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
 226  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
 227  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
 228  x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
 
 229  x "AF_MAX"
 230
 231static const char *const af_family_key_strings[AF_MAX+1] = {
 232	_sock_locks("sk_lock-")
 233};
 234static const char *const af_family_slock_key_strings[AF_MAX+1] = {
 235	_sock_locks("slock-")
 236};
 237static const char *const af_family_clock_key_strings[AF_MAX+1] = {
 238	_sock_locks("clock-")
 239};
 240
 241static const char *const af_family_kern_key_strings[AF_MAX+1] = {
 242	_sock_locks("k-sk_lock-")
 243};
 244static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
 245	_sock_locks("k-slock-")
 246};
 247static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
 248	_sock_locks("k-clock-")
 249};
 250static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
 251	_sock_locks("rlock-")
 252};
 253static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
 254	_sock_locks("wlock-")
 255};
 256static const char *const af_family_elock_key_strings[AF_MAX+1] = {
 257	_sock_locks("elock-")
 258};
 259
 260/*
 261 * sk_callback_lock and sk queues locking rules are per-address-family,
 262 * so split the lock classes by using a per-AF key:
 263 */
 264static struct lock_class_key af_callback_keys[AF_MAX];
 265static struct lock_class_key af_rlock_keys[AF_MAX];
 266static struct lock_class_key af_wlock_keys[AF_MAX];
 267static struct lock_class_key af_elock_keys[AF_MAX];
 268static struct lock_class_key af_kern_callback_keys[AF_MAX];
 269
 270/* Run time adjustable parameters. */
 271__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 272EXPORT_SYMBOL(sysctl_wmem_max);
 273__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 274EXPORT_SYMBOL(sysctl_rmem_max);
 275__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 276__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 277
 278/* Maximal space eaten by iovec or ancillary data plus some space */
 279int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
 280EXPORT_SYMBOL(sysctl_optmem_max);
 281
 282int sysctl_tstamp_allow_data __read_mostly = 1;
 283
 284DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
 285EXPORT_SYMBOL_GPL(memalloc_socks_key);
 286
 287/**
 288 * sk_set_memalloc - sets %SOCK_MEMALLOC
 289 * @sk: socket to set it on
 290 *
 291 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 292 * It's the responsibility of the admin to adjust min_free_kbytes
 293 * to meet the requirements
 294 */
 295void sk_set_memalloc(struct sock *sk)
 296{
 297	sock_set_flag(sk, SOCK_MEMALLOC);
 298	sk->sk_allocation |= __GFP_MEMALLOC;
 299	static_branch_inc(&memalloc_socks_key);
 300}
 301EXPORT_SYMBOL_GPL(sk_set_memalloc);
 302
 303void sk_clear_memalloc(struct sock *sk)
 304{
 305	sock_reset_flag(sk, SOCK_MEMALLOC);
 306	sk->sk_allocation &= ~__GFP_MEMALLOC;
 307	static_branch_dec(&memalloc_socks_key);
 308
 309	/*
 310	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 311	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 312	 * it has rmem allocations due to the last swapfile being deactivated
 313	 * but there is a risk that the socket is unusable due to exceeding
 314	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 315	 */
 316	sk_mem_reclaim(sk);
 317}
 318EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 319
 320int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 321{
 322	int ret;
 323	unsigned int noreclaim_flag;
 324
 325	/* these should have been dropped before queueing */
 326	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 327
 328	noreclaim_flag = memalloc_noreclaim_save();
 329	ret = sk->sk_backlog_rcv(sk, skb);
 
 
 
 330	memalloc_noreclaim_restore(noreclaim_flag);
 331
 332	return ret;
 333}
 334EXPORT_SYMBOL(__sk_backlog_rcv);
 335
 336void sk_error_report(struct sock *sk)
 337{
 338	sk->sk_error_report(sk);
 339
 340	switch (sk->sk_family) {
 341	case AF_INET:
 342		fallthrough;
 343	case AF_INET6:
 344		trace_inet_sk_error_report(sk);
 345		break;
 346	default:
 347		break;
 348	}
 349}
 350EXPORT_SYMBOL(sk_error_report);
 351
 352static int sock_get_timeout(long timeo, void *optval, bool old_timeval)
 353{
 354	struct __kernel_sock_timeval tv;
 355
 356	if (timeo == MAX_SCHEDULE_TIMEOUT) {
 357		tv.tv_sec = 0;
 358		tv.tv_usec = 0;
 359	} else {
 360		tv.tv_sec = timeo / HZ;
 361		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
 362	}
 363
 364	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 365		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
 366		*(struct old_timeval32 *)optval = tv32;
 367		return sizeof(tv32);
 368	}
 369
 370	if (old_timeval) {
 371		struct __kernel_old_timeval old_tv;
 372		old_tv.tv_sec = tv.tv_sec;
 373		old_tv.tv_usec = tv.tv_usec;
 374		*(struct __kernel_old_timeval *)optval = old_tv;
 375		return sizeof(old_tv);
 376	}
 377
 378	*(struct __kernel_sock_timeval *)optval = tv;
 379	return sizeof(tv);
 380}
 
 381
 382static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
 383			    bool old_timeval)
 384{
 385	struct __kernel_sock_timeval tv;
 386
 387	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 388		struct old_timeval32 tv32;
 389
 390		if (optlen < sizeof(tv32))
 391			return -EINVAL;
 392
 393		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
 394			return -EFAULT;
 395		tv.tv_sec = tv32.tv_sec;
 396		tv.tv_usec = tv32.tv_usec;
 397	} else if (old_timeval) {
 398		struct __kernel_old_timeval old_tv;
 399
 400		if (optlen < sizeof(old_tv))
 401			return -EINVAL;
 402		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
 403			return -EFAULT;
 404		tv.tv_sec = old_tv.tv_sec;
 405		tv.tv_usec = old_tv.tv_usec;
 406	} else {
 407		if (optlen < sizeof(tv))
 408			return -EINVAL;
 409		if (copy_from_sockptr(&tv, optval, sizeof(tv)))
 410			return -EFAULT;
 411	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 412	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 413		return -EDOM;
 414
 415	if (tv.tv_sec < 0) {
 416		static int warned __read_mostly;
 417
 418		*timeo_p = 0;
 419		if (warned < 10 && net_ratelimit()) {
 420			warned++;
 421			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 422				__func__, current->comm, task_pid_nr(current));
 423		}
 424		return 0;
 425	}
 426	*timeo_p = MAX_SCHEDULE_TIMEOUT;
 427	if (tv.tv_sec == 0 && tv.tv_usec == 0)
 428		return 0;
 429	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
 430		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
 431	return 0;
 432}
 433
 434static bool sock_needs_netstamp(const struct sock *sk)
 435{
 436	switch (sk->sk_family) {
 437	case AF_UNSPEC:
 438	case AF_UNIX:
 439		return false;
 440	default:
 441		return true;
 442	}
 443}
 444
 445static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 446{
 447	if (sk->sk_flags & flags) {
 448		sk->sk_flags &= ~flags;
 449		if (sock_needs_netstamp(sk) &&
 450		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 451			net_disable_timestamp();
 452	}
 453}
 454
 455
 456int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 457{
 458	unsigned long flags;
 459	struct sk_buff_head *list = &sk->sk_receive_queue;
 460
 461	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
 462		atomic_inc(&sk->sk_drops);
 463		trace_sock_rcvqueue_full(sk, skb);
 464		return -ENOMEM;
 465	}
 466
 467	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 468		atomic_inc(&sk->sk_drops);
 469		return -ENOBUFS;
 470	}
 471
 472	skb->dev = NULL;
 473	skb_set_owner_r(skb, sk);
 474
 475	/* we escape from rcu protected region, make sure we dont leak
 476	 * a norefcounted dst
 477	 */
 478	skb_dst_force(skb);
 479
 480	spin_lock_irqsave(&list->lock, flags);
 481	sock_skb_set_dropcount(sk, skb);
 482	__skb_queue_tail(list, skb);
 483	spin_unlock_irqrestore(&list->lock, flags);
 484
 485	if (!sock_flag(sk, SOCK_DEAD))
 486		sk->sk_data_ready(sk);
 487	return 0;
 488}
 489EXPORT_SYMBOL(__sock_queue_rcv_skb);
 490
 491int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 492{
 
 493	int err;
 494
 495	err = sk_filter(sk, skb);
 496	if (err)
 497		return err;
 498
 499	return __sock_queue_rcv_skb(sk, skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 500}
 501EXPORT_SYMBOL(sock_queue_rcv_skb);
 502
 503int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
 504		     const int nested, unsigned int trim_cap, bool refcounted)
 505{
 506	int rc = NET_RX_SUCCESS;
 507
 508	if (sk_filter_trim_cap(sk, skb, trim_cap))
 509		goto discard_and_relse;
 510
 511	skb->dev = NULL;
 512
 513	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 514		atomic_inc(&sk->sk_drops);
 515		goto discard_and_relse;
 516	}
 517	if (nested)
 518		bh_lock_sock_nested(sk);
 519	else
 520		bh_lock_sock(sk);
 521	if (!sock_owned_by_user(sk)) {
 522		/*
 523		 * trylock + unlock semantics:
 524		 */
 525		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 526
 527		rc = sk_backlog_rcv(sk, skb);
 528
 529		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
 530	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
 531		bh_unlock_sock(sk);
 532		atomic_inc(&sk->sk_drops);
 533		goto discard_and_relse;
 534	}
 535
 536	bh_unlock_sock(sk);
 537out:
 538	if (refcounted)
 539		sock_put(sk);
 540	return rc;
 541discard_and_relse:
 542	kfree_skb(skb);
 543	goto out;
 544}
 545EXPORT_SYMBOL(__sk_receive_skb);
 546
 547INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
 548							  u32));
 549INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
 550							   u32));
 551struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 552{
 553	struct dst_entry *dst = __sk_dst_get(sk);
 554
 555	if (dst && dst->obsolete &&
 556	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 557			       dst, cookie) == NULL) {
 558		sk_tx_queue_clear(sk);
 559		sk->sk_dst_pending_confirm = 0;
 560		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 561		dst_release(dst);
 562		return NULL;
 563	}
 564
 565	return dst;
 566}
 567EXPORT_SYMBOL(__sk_dst_check);
 568
 569struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 570{
 571	struct dst_entry *dst = sk_dst_get(sk);
 572
 573	if (dst && dst->obsolete &&
 574	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 575			       dst, cookie) == NULL) {
 576		sk_dst_reset(sk);
 577		dst_release(dst);
 578		return NULL;
 579	}
 580
 581	return dst;
 582}
 583EXPORT_SYMBOL(sk_dst_check);
 584
 585static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
 586{
 587	int ret = -ENOPROTOOPT;
 588#ifdef CONFIG_NETDEVICES
 589	struct net *net = sock_net(sk);
 590
 591	/* Sorry... */
 592	ret = -EPERM;
 593	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
 594		goto out;
 595
 596	ret = -EINVAL;
 597	if (ifindex < 0)
 598		goto out;
 599
 600	sk->sk_bound_dev_if = ifindex;
 
 
 601	if (sk->sk_prot->rehash)
 602		sk->sk_prot->rehash(sk);
 603	sk_dst_reset(sk);
 604
 605	ret = 0;
 606
 607out:
 608#endif
 609
 610	return ret;
 611}
 612
 613int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
 614{
 615	int ret;
 616
 617	if (lock_sk)
 618		lock_sock(sk);
 619	ret = sock_bindtoindex_locked(sk, ifindex);
 620	if (lock_sk)
 621		release_sock(sk);
 622
 623	return ret;
 624}
 625EXPORT_SYMBOL(sock_bindtoindex);
 626
 627static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
 628{
 629	int ret = -ENOPROTOOPT;
 630#ifdef CONFIG_NETDEVICES
 631	struct net *net = sock_net(sk);
 632	char devname[IFNAMSIZ];
 633	int index;
 634
 635	ret = -EINVAL;
 636	if (optlen < 0)
 637		goto out;
 638
 639	/* Bind this socket to a particular device like "eth0",
 640	 * as specified in the passed interface name. If the
 641	 * name is "" or the option length is zero the socket
 642	 * is not bound.
 643	 */
 644	if (optlen > IFNAMSIZ - 1)
 645		optlen = IFNAMSIZ - 1;
 646	memset(devname, 0, sizeof(devname));
 647
 648	ret = -EFAULT;
 649	if (copy_from_sockptr(devname, optval, optlen))
 650		goto out;
 651
 652	index = 0;
 653	if (devname[0] != '\0') {
 654		struct net_device *dev;
 655
 656		rcu_read_lock();
 657		dev = dev_get_by_name_rcu(net, devname);
 658		if (dev)
 659			index = dev->ifindex;
 660		rcu_read_unlock();
 661		ret = -ENODEV;
 662		if (!dev)
 663			goto out;
 664	}
 665
 666	return sock_bindtoindex(sk, index, true);
 
 
 667out:
 668#endif
 669
 670	return ret;
 671}
 672
 673static int sock_getbindtodevice(struct sock *sk, char __user *optval,
 674				int __user *optlen, int len)
 675{
 676	int ret = -ENOPROTOOPT;
 677#ifdef CONFIG_NETDEVICES
 
 678	struct net *net = sock_net(sk);
 679	char devname[IFNAMSIZ];
 680
 681	if (sk->sk_bound_dev_if == 0) {
 682		len = 0;
 683		goto zero;
 684	}
 685
 686	ret = -EINVAL;
 687	if (len < IFNAMSIZ)
 688		goto out;
 689
 690	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
 691	if (ret)
 692		goto out;
 693
 694	len = strlen(devname) + 1;
 695
 696	ret = -EFAULT;
 697	if (copy_to_user(optval, devname, len))
 698		goto out;
 699
 700zero:
 701	ret = -EFAULT;
 702	if (put_user(len, optlen))
 703		goto out;
 704
 705	ret = 0;
 706
 707out:
 708#endif
 709
 710	return ret;
 711}
 712
 713bool sk_mc_loop(struct sock *sk)
 714{
 715	if (dev_recursion_level())
 716		return false;
 717	if (!sk)
 718		return true;
 719	switch (sk->sk_family) {
 720	case AF_INET:
 721		return inet_sk(sk)->mc_loop;
 722#if IS_ENABLED(CONFIG_IPV6)
 723	case AF_INET6:
 724		return inet6_sk(sk)->mc_loop;
 725#endif
 726	}
 727	WARN_ON_ONCE(1);
 728	return true;
 729}
 730EXPORT_SYMBOL(sk_mc_loop);
 731
 732void sock_set_reuseaddr(struct sock *sk)
 733{
 734	lock_sock(sk);
 735	sk->sk_reuse = SK_CAN_REUSE;
 736	release_sock(sk);
 737}
 738EXPORT_SYMBOL(sock_set_reuseaddr);
 739
 740void sock_set_reuseport(struct sock *sk)
 741{
 742	lock_sock(sk);
 743	sk->sk_reuseport = true;
 744	release_sock(sk);
 745}
 746EXPORT_SYMBOL(sock_set_reuseport);
 747
 748void sock_no_linger(struct sock *sk)
 749{
 750	lock_sock(sk);
 751	sk->sk_lingertime = 0;
 752	sock_set_flag(sk, SOCK_LINGER);
 753	release_sock(sk);
 754}
 755EXPORT_SYMBOL(sock_no_linger);
 756
 757void sock_set_priority(struct sock *sk, u32 priority)
 758{
 759	lock_sock(sk);
 760	sk->sk_priority = priority;
 761	release_sock(sk);
 762}
 763EXPORT_SYMBOL(sock_set_priority);
 764
 765void sock_set_sndtimeo(struct sock *sk, s64 secs)
 766{
 767	lock_sock(sk);
 768	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
 769		sk->sk_sndtimeo = secs * HZ;
 770	else
 771		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
 772	release_sock(sk);
 773}
 774EXPORT_SYMBOL(sock_set_sndtimeo);
 775
 776static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
 777{
 778	if (val)  {
 779		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
 780		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
 781		sock_set_flag(sk, SOCK_RCVTSTAMP);
 782		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 783	} else {
 784		sock_reset_flag(sk, SOCK_RCVTSTAMP);
 785		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 786	}
 787}
 788
 789void sock_enable_timestamps(struct sock *sk)
 790{
 791	lock_sock(sk);
 792	__sock_set_timestamps(sk, true, false, true);
 793	release_sock(sk);
 794}
 795EXPORT_SYMBOL(sock_enable_timestamps);
 796
 797void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
 798{
 799	switch (optname) {
 800	case SO_TIMESTAMP_OLD:
 801		__sock_set_timestamps(sk, valbool, false, false);
 802		break;
 803	case SO_TIMESTAMP_NEW:
 804		__sock_set_timestamps(sk, valbool, true, false);
 805		break;
 806	case SO_TIMESTAMPNS_OLD:
 807		__sock_set_timestamps(sk, valbool, false, true);
 808		break;
 809	case SO_TIMESTAMPNS_NEW:
 810		__sock_set_timestamps(sk, valbool, true, true);
 811		break;
 812	}
 813}
 814
 815static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
 816{
 817	struct net *net = sock_net(sk);
 818	struct net_device *dev = NULL;
 819	bool match = false;
 820	int *vclock_index;
 821	int i, num;
 822
 823	if (sk->sk_bound_dev_if)
 824		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
 825
 826	if (!dev) {
 827		pr_err("%s: sock not bind to device\n", __func__);
 828		return -EOPNOTSUPP;
 829	}
 830
 831	num = ethtool_get_phc_vclocks(dev, &vclock_index);
 
 
 832	for (i = 0; i < num; i++) {
 833		if (*(vclock_index + i) == phc_index) {
 834			match = true;
 835			break;
 836		}
 837	}
 838
 839	if (num > 0)
 840		kfree(vclock_index);
 841
 842	if (!match)
 843		return -EINVAL;
 844
 845	sk->sk_bind_phc = phc_index;
 846
 847	return 0;
 848}
 849
 850int sock_set_timestamping(struct sock *sk, int optname,
 851			  struct so_timestamping timestamping)
 852{
 853	int val = timestamping.flags;
 854	int ret;
 855
 856	if (val & ~SOF_TIMESTAMPING_MASK)
 857		return -EINVAL;
 858
 
 
 
 
 859	if (val & SOF_TIMESTAMPING_OPT_ID &&
 860	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
 861		if (sk->sk_protocol == IPPROTO_TCP &&
 862		    sk->sk_type == SOCK_STREAM) {
 863			if ((1 << sk->sk_state) &
 864			    (TCPF_CLOSE | TCPF_LISTEN))
 865				return -EINVAL;
 866			sk->sk_tskey = tcp_sk(sk)->snd_una;
 
 
 
 867		} else {
 868			sk->sk_tskey = 0;
 869		}
 870	}
 871
 872	if (val & SOF_TIMESTAMPING_OPT_STATS &&
 873	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
 874		return -EINVAL;
 875
 876	if (val & SOF_TIMESTAMPING_BIND_PHC) {
 877		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
 878		if (ret)
 879			return ret;
 880	}
 881
 882	sk->sk_tsflags = val;
 883	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
 884
 885	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
 886		sock_enable_timestamp(sk,
 887				      SOCK_TIMESTAMPING_RX_SOFTWARE);
 888	else
 889		sock_disable_timestamp(sk,
 890				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
 891	return 0;
 892}
 893
 894void sock_set_keepalive(struct sock *sk)
 895{
 896	lock_sock(sk);
 897	if (sk->sk_prot->keepalive)
 898		sk->sk_prot->keepalive(sk, true);
 899	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
 900	release_sock(sk);
 901}
 902EXPORT_SYMBOL(sock_set_keepalive);
 903
 904static void __sock_set_rcvbuf(struct sock *sk, int val)
 905{
 906	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
 907	 * as a negative value.
 908	 */
 909	val = min_t(int, val, INT_MAX / 2);
 910	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 911
 912	/* We double it on the way in to account for "struct sk_buff" etc.
 913	 * overhead.   Applications assume that the SO_RCVBUF setting they make
 914	 * will allow that much actual data to be received on that socket.
 915	 *
 916	 * Applications are unaware that "struct sk_buff" and other overheads
 917	 * allocate from the receive buffer during socket buffer allocation.
 918	 *
 919	 * And after considering the possible alternatives, returning the value
 920	 * we actually used in getsockopt is the most desirable behavior.
 921	 */
 922	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
 923}
 924
 925void sock_set_rcvbuf(struct sock *sk, int val)
 926{
 927	lock_sock(sk);
 928	__sock_set_rcvbuf(sk, val);
 929	release_sock(sk);
 930}
 931EXPORT_SYMBOL(sock_set_rcvbuf);
 932
 933static void __sock_set_mark(struct sock *sk, u32 val)
 934{
 935	if (val != sk->sk_mark) {
 936		sk->sk_mark = val;
 937		sk_dst_reset(sk);
 938	}
 939}
 940
 941void sock_set_mark(struct sock *sk, u32 val)
 942{
 943	lock_sock(sk);
 944	__sock_set_mark(sk, val);
 945	release_sock(sk);
 946}
 947EXPORT_SYMBOL(sock_set_mark);
 948
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 949/*
 950 *	This is meant for all protocols to use and covers goings on
 951 *	at the socket level. Everything here is generic.
 952 */
 953
 954int sock_setsockopt(struct socket *sock, int level, int optname,
 955		    sockptr_t optval, unsigned int optlen)
 956{
 957	struct so_timestamping timestamping;
 
 958	struct sock_txtime sk_txtime;
 959	struct sock *sk = sock->sk;
 960	int val;
 961	int valbool;
 962	struct linger ling;
 963	int ret = 0;
 964
 965	/*
 966	 *	Options without arguments
 967	 */
 968
 969	if (optname == SO_BINDTODEVICE)
 970		return sock_setbindtodevice(sk, optval, optlen);
 971
 972	if (optlen < sizeof(int))
 973		return -EINVAL;
 974
 975	if (copy_from_sockptr(&val, optval, sizeof(val)))
 976		return -EFAULT;
 977
 978	valbool = val ? 1 : 0;
 979
 980	lock_sock(sk);
 981
 982	switch (optname) {
 983	case SO_DEBUG:
 984		if (val && !capable(CAP_NET_ADMIN))
 985			ret = -EACCES;
 986		else
 987			sock_valbool_flag(sk, SOCK_DBG, valbool);
 988		break;
 989	case SO_REUSEADDR:
 990		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
 991		break;
 992	case SO_REUSEPORT:
 993		sk->sk_reuseport = valbool;
 994		break;
 995	case SO_TYPE:
 996	case SO_PROTOCOL:
 997	case SO_DOMAIN:
 998	case SO_ERROR:
 999		ret = -ENOPROTOOPT;
1000		break;
1001	case SO_DONTROUTE:
1002		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1003		sk_dst_reset(sk);
1004		break;
1005	case SO_BROADCAST:
1006		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1007		break;
1008	case SO_SNDBUF:
1009		/* Don't error on this BSD doesn't and if you think
1010		 * about it this is right. Otherwise apps have to
1011		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1012		 * are treated in BSD as hints
1013		 */
1014		val = min_t(u32, val, sysctl_wmem_max);
1015set_sndbuf:
1016		/* Ensure val * 2 fits into an int, to prevent max_t()
1017		 * from treating it as a negative value.
1018		 */
1019		val = min_t(int, val, INT_MAX / 2);
1020		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1021		WRITE_ONCE(sk->sk_sndbuf,
1022			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1023		/* Wake up sending tasks if we upped the value. */
1024		sk->sk_write_space(sk);
1025		break;
1026
1027	case SO_SNDBUFFORCE:
1028		if (!capable(CAP_NET_ADMIN)) {
1029			ret = -EPERM;
1030			break;
1031		}
1032
1033		/* No negative values (to prevent underflow, as val will be
1034		 * multiplied by 2).
1035		 */
1036		if (val < 0)
1037			val = 0;
1038		goto set_sndbuf;
1039
1040	case SO_RCVBUF:
1041		/* Don't error on this BSD doesn't and if you think
1042		 * about it this is right. Otherwise apps have to
1043		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1044		 * are treated in BSD as hints
1045		 */
1046		__sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max));
1047		break;
1048
1049	case SO_RCVBUFFORCE:
1050		if (!capable(CAP_NET_ADMIN)) {
1051			ret = -EPERM;
1052			break;
1053		}
1054
1055		/* No negative values (to prevent underflow, as val will be
1056		 * multiplied by 2).
1057		 */
1058		__sock_set_rcvbuf(sk, max(val, 0));
1059		break;
1060
1061	case SO_KEEPALIVE:
1062		if (sk->sk_prot->keepalive)
1063			sk->sk_prot->keepalive(sk, valbool);
1064		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1065		break;
1066
1067	case SO_OOBINLINE:
1068		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1069		break;
1070
1071	case SO_NO_CHECK:
1072		sk->sk_no_check_tx = valbool;
1073		break;
1074
1075	case SO_PRIORITY:
1076		if ((val >= 0 && val <= 6) ||
1077		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 
1078			sk->sk_priority = val;
1079		else
1080			ret = -EPERM;
1081		break;
1082
1083	case SO_LINGER:
1084		if (optlen < sizeof(ling)) {
1085			ret = -EINVAL;	/* 1003.1g */
1086			break;
1087		}
1088		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1089			ret = -EFAULT;
1090			break;
1091		}
1092		if (!ling.l_onoff)
1093			sock_reset_flag(sk, SOCK_LINGER);
1094		else {
1095#if (BITS_PER_LONG == 32)
1096			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1097				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1098			else
1099#endif
1100				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1101			sock_set_flag(sk, SOCK_LINGER);
1102		}
1103		break;
1104
1105	case SO_BSDCOMPAT:
1106		break;
1107
1108	case SO_PASSCRED:
1109		if (valbool)
1110			set_bit(SOCK_PASSCRED, &sock->flags);
1111		else
1112			clear_bit(SOCK_PASSCRED, &sock->flags);
1113		break;
1114
1115	case SO_TIMESTAMP_OLD:
1116	case SO_TIMESTAMP_NEW:
1117	case SO_TIMESTAMPNS_OLD:
1118	case SO_TIMESTAMPNS_NEW:
1119		sock_set_timestamp(sk, optname, valbool);
1120		break;
1121
1122	case SO_TIMESTAMPING_NEW:
1123	case SO_TIMESTAMPING_OLD:
1124		if (optlen == sizeof(timestamping)) {
1125			if (copy_from_sockptr(&timestamping, optval,
1126					      sizeof(timestamping))) {
1127				ret = -EFAULT;
1128				break;
1129			}
1130		} else {
1131			memset(&timestamping, 0, sizeof(timestamping));
1132			timestamping.flags = val;
1133		}
1134		ret = sock_set_timestamping(sk, optname, timestamping);
1135		break;
1136
1137	case SO_RCVLOWAT:
1138		if (val < 0)
1139			val = INT_MAX;
1140		if (sock->ops->set_rcvlowat)
1141			ret = sock->ops->set_rcvlowat(sk, val);
1142		else
1143			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1144		break;
1145
1146	case SO_RCVTIMEO_OLD:
1147	case SO_RCVTIMEO_NEW:
1148		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1149				       optlen, optname == SO_RCVTIMEO_OLD);
1150		break;
1151
1152	case SO_SNDTIMEO_OLD:
1153	case SO_SNDTIMEO_NEW:
1154		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1155				       optlen, optname == SO_SNDTIMEO_OLD);
1156		break;
1157
1158	case SO_ATTACH_FILTER: {
1159		struct sock_fprog fprog;
1160
1161		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1162		if (!ret)
1163			ret = sk_attach_filter(&fprog, sk);
1164		break;
1165	}
1166	case SO_ATTACH_BPF:
1167		ret = -EINVAL;
1168		if (optlen == sizeof(u32)) {
1169			u32 ufd;
1170
1171			ret = -EFAULT;
1172			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1173				break;
1174
1175			ret = sk_attach_bpf(ufd, sk);
1176		}
1177		break;
1178
1179	case SO_ATTACH_REUSEPORT_CBPF: {
1180		struct sock_fprog fprog;
1181
1182		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1183		if (!ret)
1184			ret = sk_reuseport_attach_filter(&fprog, sk);
1185		break;
1186	}
1187	case SO_ATTACH_REUSEPORT_EBPF:
1188		ret = -EINVAL;
1189		if (optlen == sizeof(u32)) {
1190			u32 ufd;
1191
1192			ret = -EFAULT;
1193			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1194				break;
1195
1196			ret = sk_reuseport_attach_bpf(ufd, sk);
1197		}
1198		break;
1199
1200	case SO_DETACH_REUSEPORT_BPF:
1201		ret = reuseport_detach_prog(sk);
1202		break;
1203
1204	case SO_DETACH_FILTER:
1205		ret = sk_detach_filter(sk);
1206		break;
1207
1208	case SO_LOCK_FILTER:
1209		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1210			ret = -EPERM;
1211		else
1212			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1213		break;
1214
1215	case SO_PASSSEC:
1216		if (valbool)
1217			set_bit(SOCK_PASSSEC, &sock->flags);
1218		else
1219			clear_bit(SOCK_PASSSEC, &sock->flags);
1220		break;
1221	case SO_MARK:
1222		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
 
1223			ret = -EPERM;
1224			break;
1225		}
1226
1227		__sock_set_mark(sk, val);
1228		break;
 
 
 
 
 
 
 
 
 
1229
1230	case SO_RXQ_OVFL:
1231		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1232		break;
1233
1234	case SO_WIFI_STATUS:
1235		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1236		break;
1237
1238	case SO_PEEK_OFF:
1239		if (sock->ops->set_peek_off)
1240			ret = sock->ops->set_peek_off(sk, val);
1241		else
1242			ret = -EOPNOTSUPP;
1243		break;
1244
1245	case SO_NOFCS:
1246		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1247		break;
1248
1249	case SO_SELECT_ERR_QUEUE:
1250		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1251		break;
1252
1253#ifdef CONFIG_NET_RX_BUSY_POLL
1254	case SO_BUSY_POLL:
1255		/* allow unprivileged users to decrease the value */
1256		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1257			ret = -EPERM;
1258		else {
1259			if (val < 0)
1260				ret = -EINVAL;
1261			else
1262				WRITE_ONCE(sk->sk_ll_usec, val);
1263		}
1264		break;
1265	case SO_PREFER_BUSY_POLL:
1266		if (valbool && !capable(CAP_NET_ADMIN))
1267			ret = -EPERM;
1268		else
1269			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1270		break;
1271	case SO_BUSY_POLL_BUDGET:
1272		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !capable(CAP_NET_ADMIN)) {
1273			ret = -EPERM;
1274		} else {
1275			if (val < 0 || val > U16_MAX)
1276				ret = -EINVAL;
1277			else
1278				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1279		}
1280		break;
1281#endif
1282
1283	case SO_MAX_PACING_RATE:
1284		{
1285		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1286
1287		if (sizeof(ulval) != sizeof(val) &&
1288		    optlen >= sizeof(ulval) &&
1289		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1290			ret = -EFAULT;
1291			break;
1292		}
1293		if (ulval != ~0UL)
1294			cmpxchg(&sk->sk_pacing_status,
1295				SK_PACING_NONE,
1296				SK_PACING_NEEDED);
1297		sk->sk_max_pacing_rate = ulval;
1298		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1299		break;
1300		}
1301	case SO_INCOMING_CPU:
1302		WRITE_ONCE(sk->sk_incoming_cpu, val);
1303		break;
1304
1305	case SO_CNX_ADVICE:
1306		if (val == 1)
1307			dst_negative_advice(sk);
1308		break;
1309
1310	case SO_ZEROCOPY:
1311		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1312			if (!((sk->sk_type == SOCK_STREAM &&
1313			       sk->sk_protocol == IPPROTO_TCP) ||
1314			      (sk->sk_type == SOCK_DGRAM &&
1315			       sk->sk_protocol == IPPROTO_UDP)))
1316				ret = -ENOTSUPP;
1317		} else if (sk->sk_family != PF_RDS) {
1318			ret = -ENOTSUPP;
1319		}
1320		if (!ret) {
1321			if (val < 0 || val > 1)
1322				ret = -EINVAL;
1323			else
1324				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1325		}
1326		break;
1327
1328	case SO_TXTIME:
1329		if (optlen != sizeof(struct sock_txtime)) {
1330			ret = -EINVAL;
1331			break;
1332		} else if (copy_from_sockptr(&sk_txtime, optval,
1333			   sizeof(struct sock_txtime))) {
1334			ret = -EFAULT;
1335			break;
1336		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1337			ret = -EINVAL;
1338			break;
1339		}
1340		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1341		 * scheduler has enough safe guards.
1342		 */
1343		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1344		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1345			ret = -EPERM;
1346			break;
1347		}
1348		sock_valbool_flag(sk, SOCK_TXTIME, true);
1349		sk->sk_clockid = sk_txtime.clockid;
1350		sk->sk_txtime_deadline_mode =
1351			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1352		sk->sk_txtime_report_errors =
1353			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1354		break;
1355
1356	case SO_BINDTOIFINDEX:
1357		ret = sock_bindtoindex_locked(sk, val);
1358		break;
1359
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1360	default:
1361		ret = -ENOPROTOOPT;
1362		break;
1363	}
1364	release_sock(sk);
1365	return ret;
1366}
 
 
 
 
 
 
 
1367EXPORT_SYMBOL(sock_setsockopt);
1368
1369static const struct cred *sk_get_peer_cred(struct sock *sk)
1370{
1371	const struct cred *cred;
1372
1373	spin_lock(&sk->sk_peer_lock);
1374	cred = get_cred(sk->sk_peer_cred);
1375	spin_unlock(&sk->sk_peer_lock);
1376
1377	return cred;
1378}
1379
1380static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1381			  struct ucred *ucred)
1382{
1383	ucred->pid = pid_vnr(pid);
1384	ucred->uid = ucred->gid = -1;
1385	if (cred) {
1386		struct user_namespace *current_ns = current_user_ns();
1387
1388		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1389		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1390	}
1391}
1392
1393static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1394{
1395	struct user_namespace *user_ns = current_user_ns();
1396	int i;
1397
1398	for (i = 0; i < src->ngroups; i++)
1399		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
 
 
1400			return -EFAULT;
 
1401
1402	return 0;
1403}
1404
1405int sock_getsockopt(struct socket *sock, int level, int optname,
1406		    char __user *optval, int __user *optlen)
1407{
1408	struct sock *sk = sock->sk;
1409
1410	union {
1411		int val;
1412		u64 val64;
1413		unsigned long ulval;
1414		struct linger ling;
1415		struct old_timeval32 tm32;
1416		struct __kernel_old_timeval tm;
1417		struct  __kernel_sock_timeval stm;
1418		struct sock_txtime txtime;
1419		struct so_timestamping timestamping;
1420	} v;
1421
1422	int lv = sizeof(int);
1423	int len;
1424
1425	if (get_user(len, optlen))
1426		return -EFAULT;
1427	if (len < 0)
1428		return -EINVAL;
1429
1430	memset(&v, 0, sizeof(v));
1431
1432	switch (optname) {
1433	case SO_DEBUG:
1434		v.val = sock_flag(sk, SOCK_DBG);
1435		break;
1436
1437	case SO_DONTROUTE:
1438		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1439		break;
1440
1441	case SO_BROADCAST:
1442		v.val = sock_flag(sk, SOCK_BROADCAST);
1443		break;
1444
1445	case SO_SNDBUF:
1446		v.val = sk->sk_sndbuf;
1447		break;
1448
1449	case SO_RCVBUF:
1450		v.val = sk->sk_rcvbuf;
1451		break;
1452
1453	case SO_REUSEADDR:
1454		v.val = sk->sk_reuse;
1455		break;
1456
1457	case SO_REUSEPORT:
1458		v.val = sk->sk_reuseport;
1459		break;
1460
1461	case SO_KEEPALIVE:
1462		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1463		break;
1464
1465	case SO_TYPE:
1466		v.val = sk->sk_type;
1467		break;
1468
1469	case SO_PROTOCOL:
1470		v.val = sk->sk_protocol;
1471		break;
1472
1473	case SO_DOMAIN:
1474		v.val = sk->sk_family;
1475		break;
1476
1477	case SO_ERROR:
1478		v.val = -sock_error(sk);
1479		if (v.val == 0)
1480			v.val = xchg(&sk->sk_err_soft, 0);
1481		break;
1482
1483	case SO_OOBINLINE:
1484		v.val = sock_flag(sk, SOCK_URGINLINE);
1485		break;
1486
1487	case SO_NO_CHECK:
1488		v.val = sk->sk_no_check_tx;
1489		break;
1490
1491	case SO_PRIORITY:
1492		v.val = sk->sk_priority;
1493		break;
1494
1495	case SO_LINGER:
1496		lv		= sizeof(v.ling);
1497		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1498		v.ling.l_linger	= sk->sk_lingertime / HZ;
1499		break;
1500
1501	case SO_BSDCOMPAT:
1502		break;
1503
1504	case SO_TIMESTAMP_OLD:
1505		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1506				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1507				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1508		break;
1509
1510	case SO_TIMESTAMPNS_OLD:
1511		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1512		break;
1513
1514	case SO_TIMESTAMP_NEW:
1515		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1516		break;
1517
1518	case SO_TIMESTAMPNS_NEW:
1519		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1520		break;
1521
1522	case SO_TIMESTAMPING_OLD:
1523		lv = sizeof(v.timestamping);
1524		v.timestamping.flags = sk->sk_tsflags;
1525		v.timestamping.bind_phc = sk->sk_bind_phc;
1526		break;
1527
1528	case SO_RCVTIMEO_OLD:
1529	case SO_RCVTIMEO_NEW:
1530		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1531		break;
1532
1533	case SO_SNDTIMEO_OLD:
1534	case SO_SNDTIMEO_NEW:
1535		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1536		break;
1537
1538	case SO_RCVLOWAT:
1539		v.val = sk->sk_rcvlowat;
1540		break;
1541
1542	case SO_SNDLOWAT:
1543		v.val = 1;
1544		break;
1545
1546	case SO_PASSCRED:
1547		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1548		break;
1549
1550	case SO_PEERCRED:
1551	{
1552		struct ucred peercred;
1553		if (len > sizeof(peercred))
1554			len = sizeof(peercred);
1555
1556		spin_lock(&sk->sk_peer_lock);
1557		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1558		spin_unlock(&sk->sk_peer_lock);
1559
1560		if (copy_to_user(optval, &peercred, len))
1561			return -EFAULT;
1562		goto lenout;
1563	}
1564
1565	case SO_PEERGROUPS:
1566	{
1567		const struct cred *cred;
1568		int ret, n;
1569
1570		cred = sk_get_peer_cred(sk);
1571		if (!cred)
1572			return -ENODATA;
1573
1574		n = cred->group_info->ngroups;
1575		if (len < n * sizeof(gid_t)) {
1576			len = n * sizeof(gid_t);
1577			put_cred(cred);
1578			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1579		}
1580		len = n * sizeof(gid_t);
1581
1582		ret = groups_to_user((gid_t __user *)optval, cred->group_info);
1583		put_cred(cred);
1584		if (ret)
1585			return ret;
1586		goto lenout;
1587	}
1588
1589	case SO_PEERNAME:
1590	{
1591		char address[128];
1592
1593		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1594		if (lv < 0)
1595			return -ENOTCONN;
1596		if (lv < len)
1597			return -EINVAL;
1598		if (copy_to_user(optval, address, len))
1599			return -EFAULT;
1600		goto lenout;
1601	}
1602
1603	/* Dubious BSD thing... Probably nobody even uses it, but
1604	 * the UNIX standard wants it for whatever reason... -DaveM
1605	 */
1606	case SO_ACCEPTCONN:
1607		v.val = sk->sk_state == TCP_LISTEN;
1608		break;
1609
1610	case SO_PASSSEC:
1611		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1612		break;
1613
1614	case SO_PEERSEC:
1615		return security_socket_getpeersec_stream(sock, optval, optlen, len);
 
1616
1617	case SO_MARK:
1618		v.val = sk->sk_mark;
1619		break;
1620
 
 
 
 
1621	case SO_RXQ_OVFL:
1622		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1623		break;
1624
1625	case SO_WIFI_STATUS:
1626		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1627		break;
1628
1629	case SO_PEEK_OFF:
1630		if (!sock->ops->set_peek_off)
1631			return -EOPNOTSUPP;
1632
1633		v.val = sk->sk_peek_off;
1634		break;
1635	case SO_NOFCS:
1636		v.val = sock_flag(sk, SOCK_NOFCS);
1637		break;
1638
1639	case SO_BINDTODEVICE:
1640		return sock_getbindtodevice(sk, optval, optlen, len);
1641
1642	case SO_GET_FILTER:
1643		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1644		if (len < 0)
1645			return len;
1646
1647		goto lenout;
1648
1649	case SO_LOCK_FILTER:
1650		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1651		break;
1652
1653	case SO_BPF_EXTENSIONS:
1654		v.val = bpf_tell_extensions();
1655		break;
1656
1657	case SO_SELECT_ERR_QUEUE:
1658		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1659		break;
1660
1661#ifdef CONFIG_NET_RX_BUSY_POLL
1662	case SO_BUSY_POLL:
1663		v.val = sk->sk_ll_usec;
1664		break;
1665	case SO_PREFER_BUSY_POLL:
1666		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1667		break;
1668#endif
1669
1670	case SO_MAX_PACING_RATE:
1671		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1672			lv = sizeof(v.ulval);
1673			v.ulval = sk->sk_max_pacing_rate;
1674		} else {
1675			/* 32bit version */
1676			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1677		}
1678		break;
1679
1680	case SO_INCOMING_CPU:
1681		v.val = READ_ONCE(sk->sk_incoming_cpu);
1682		break;
1683
1684	case SO_MEMINFO:
1685	{
1686		u32 meminfo[SK_MEMINFO_VARS];
1687
1688		sk_get_meminfo(sk, meminfo);
1689
1690		len = min_t(unsigned int, len, sizeof(meminfo));
1691		if (copy_to_user(optval, &meminfo, len))
1692			return -EFAULT;
1693
1694		goto lenout;
1695	}
1696
1697#ifdef CONFIG_NET_RX_BUSY_POLL
1698	case SO_INCOMING_NAPI_ID:
1699		v.val = READ_ONCE(sk->sk_napi_id);
1700
1701		/* aggregate non-NAPI IDs down to 0 */
1702		if (v.val < MIN_NAPI_ID)
1703			v.val = 0;
1704
1705		break;
1706#endif
1707
1708	case SO_COOKIE:
1709		lv = sizeof(u64);
1710		if (len < lv)
1711			return -EINVAL;
1712		v.val64 = sock_gen_cookie(sk);
1713		break;
1714
1715	case SO_ZEROCOPY:
1716		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1717		break;
1718
1719	case SO_TXTIME:
1720		lv = sizeof(v.txtime);
1721		v.txtime.clockid = sk->sk_clockid;
1722		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1723				  SOF_TXTIME_DEADLINE_MODE : 0;
1724		v.txtime.flags |= sk->sk_txtime_report_errors ?
1725				  SOF_TXTIME_REPORT_ERRORS : 0;
1726		break;
1727
1728	case SO_BINDTOIFINDEX:
1729		v.val = sk->sk_bound_dev_if;
1730		break;
1731
1732	case SO_NETNS_COOKIE:
1733		lv = sizeof(u64);
1734		if (len != lv)
1735			return -EINVAL;
1736		v.val64 = sock_net(sk)->net_cookie;
1737		break;
1738
 
 
 
 
 
 
 
 
 
 
 
 
1739	default:
1740		/* We implement the SO_SNDLOWAT etc to not be settable
1741		 * (1003.1g 7).
1742		 */
1743		return -ENOPROTOOPT;
1744	}
1745
1746	if (len > lv)
1747		len = lv;
1748	if (copy_to_user(optval, &v, len))
1749		return -EFAULT;
1750lenout:
1751	if (put_user(len, optlen))
1752		return -EFAULT;
1753	return 0;
1754}
1755
 
 
 
 
 
 
 
 
1756/*
1757 * Initialize an sk_lock.
1758 *
1759 * (We also register the sk_lock with the lock validator.)
1760 */
1761static inline void sock_lock_init(struct sock *sk)
1762{
1763	if (sk->sk_kern_sock)
1764		sock_lock_init_class_and_name(
1765			sk,
1766			af_family_kern_slock_key_strings[sk->sk_family],
1767			af_family_kern_slock_keys + sk->sk_family,
1768			af_family_kern_key_strings[sk->sk_family],
1769			af_family_kern_keys + sk->sk_family);
1770	else
1771		sock_lock_init_class_and_name(
1772			sk,
1773			af_family_slock_key_strings[sk->sk_family],
1774			af_family_slock_keys + sk->sk_family,
1775			af_family_key_strings[sk->sk_family],
1776			af_family_keys + sk->sk_family);
1777}
1778
1779/*
1780 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1781 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1782 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1783 */
1784static void sock_copy(struct sock *nsk, const struct sock *osk)
1785{
1786	const struct proto *prot = READ_ONCE(osk->sk_prot);
1787#ifdef CONFIG_SECURITY_NETWORK
1788	void *sptr = nsk->sk_security;
1789#endif
1790
1791	/* If we move sk_tx_queue_mapping out of the private section,
1792	 * we must check if sk_tx_queue_clear() is called after
1793	 * sock_copy() in sk_clone_lock().
1794	 */
1795	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
1796		     offsetof(struct sock, sk_dontcopy_begin) ||
1797		     offsetof(struct sock, sk_tx_queue_mapping) >=
1798		     offsetof(struct sock, sk_dontcopy_end));
1799
1800	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1801
1802	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1803	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1804
1805#ifdef CONFIG_SECURITY_NETWORK
1806	nsk->sk_security = sptr;
1807	security_sk_clone(osk, nsk);
1808#endif
1809}
1810
1811static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1812		int family)
1813{
1814	struct sock *sk;
1815	struct kmem_cache *slab;
1816
1817	slab = prot->slab;
1818	if (slab != NULL) {
1819		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1820		if (!sk)
1821			return sk;
1822		if (want_init_on_alloc(priority))
1823			sk_prot_clear_nulls(sk, prot->obj_size);
1824	} else
1825		sk = kmalloc(prot->obj_size, priority);
1826
1827	if (sk != NULL) {
1828		if (security_sk_alloc(sk, family, priority))
1829			goto out_free;
1830
1831		if (!try_module_get(prot->owner))
1832			goto out_free_sec;
1833	}
1834
1835	return sk;
1836
1837out_free_sec:
1838	security_sk_free(sk);
1839out_free:
1840	if (slab != NULL)
1841		kmem_cache_free(slab, sk);
1842	else
1843		kfree(sk);
1844	return NULL;
1845}
1846
1847static void sk_prot_free(struct proto *prot, struct sock *sk)
1848{
1849	struct kmem_cache *slab;
1850	struct module *owner;
1851
1852	owner = prot->owner;
1853	slab = prot->slab;
1854
1855	cgroup_sk_free(&sk->sk_cgrp_data);
1856	mem_cgroup_sk_free(sk);
1857	security_sk_free(sk);
1858	if (slab != NULL)
1859		kmem_cache_free(slab, sk);
1860	else
1861		kfree(sk);
1862	module_put(owner);
1863}
1864
1865/**
1866 *	sk_alloc - All socket objects are allocated here
1867 *	@net: the applicable net namespace
1868 *	@family: protocol family
1869 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1870 *	@prot: struct proto associated with this new sock instance
1871 *	@kern: is this to be a kernel socket?
1872 */
1873struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1874		      struct proto *prot, int kern)
1875{
1876	struct sock *sk;
1877
1878	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1879	if (sk) {
1880		sk->sk_family = family;
1881		/*
1882		 * See comment in struct sock definition to understand
1883		 * why we need sk_prot_creator -acme
1884		 */
1885		sk->sk_prot = sk->sk_prot_creator = prot;
1886		sk->sk_kern_sock = kern;
1887		sock_lock_init(sk);
1888		sk->sk_net_refcnt = kern ? 0 : 1;
1889		if (likely(sk->sk_net_refcnt)) {
1890			get_net(net);
1891			sock_inuse_add(net, 1);
 
 
 
1892		}
1893
1894		sock_net_set(sk, net);
1895		refcount_set(&sk->sk_wmem_alloc, 1);
1896
1897		mem_cgroup_sk_alloc(sk);
1898		cgroup_sk_alloc(&sk->sk_cgrp_data);
1899		sock_update_classid(&sk->sk_cgrp_data);
1900		sock_update_netprioidx(&sk->sk_cgrp_data);
1901		sk_tx_queue_clear(sk);
1902	}
1903
1904	return sk;
1905}
1906EXPORT_SYMBOL(sk_alloc);
1907
1908/* Sockets having SOCK_RCU_FREE will call this function after one RCU
1909 * grace period. This is the case for UDP sockets and TCP listeners.
1910 */
1911static void __sk_destruct(struct rcu_head *head)
1912{
1913	struct sock *sk = container_of(head, struct sock, sk_rcu);
1914	struct sk_filter *filter;
1915
1916	if (sk->sk_destruct)
1917		sk->sk_destruct(sk);
1918
1919	filter = rcu_dereference_check(sk->sk_filter,
1920				       refcount_read(&sk->sk_wmem_alloc) == 0);
1921	if (filter) {
1922		sk_filter_uncharge(sk, filter);
1923		RCU_INIT_POINTER(sk->sk_filter, NULL);
1924	}
1925
1926	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1927
1928#ifdef CONFIG_BPF_SYSCALL
1929	bpf_sk_storage_free(sk);
1930#endif
1931
1932	if (atomic_read(&sk->sk_omem_alloc))
1933		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1934			 __func__, atomic_read(&sk->sk_omem_alloc));
1935
1936	if (sk->sk_frag.page) {
1937		put_page(sk->sk_frag.page);
1938		sk->sk_frag.page = NULL;
1939	}
1940
1941	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
1942	put_cred(sk->sk_peer_cred);
1943	put_pid(sk->sk_peer_pid);
1944
1945	if (likely(sk->sk_net_refcnt))
1946		put_net(sock_net(sk));
 
 
 
1947	sk_prot_free(sk->sk_prot_creator, sk);
1948}
1949
1950void sk_destruct(struct sock *sk)
1951{
1952	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
1953
1954	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
1955		reuseport_detach_sock(sk);
1956		use_call_rcu = true;
1957	}
1958
1959	if (use_call_rcu)
1960		call_rcu(&sk->sk_rcu, __sk_destruct);
1961	else
1962		__sk_destruct(&sk->sk_rcu);
1963}
1964
1965static void __sk_free(struct sock *sk)
1966{
1967	if (likely(sk->sk_net_refcnt))
1968		sock_inuse_add(sock_net(sk), -1);
1969
1970	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1971		sock_diag_broadcast_destroy(sk);
1972	else
1973		sk_destruct(sk);
1974}
1975
1976void sk_free(struct sock *sk)
1977{
1978	/*
1979	 * We subtract one from sk_wmem_alloc and can know if
1980	 * some packets are still in some tx queue.
1981	 * If not null, sock_wfree() will call __sk_free(sk) later
1982	 */
1983	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1984		__sk_free(sk);
1985}
1986EXPORT_SYMBOL(sk_free);
1987
1988static void sk_init_common(struct sock *sk)
1989{
1990	skb_queue_head_init(&sk->sk_receive_queue);
1991	skb_queue_head_init(&sk->sk_write_queue);
1992	skb_queue_head_init(&sk->sk_error_queue);
1993
1994	rwlock_init(&sk->sk_callback_lock);
1995	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1996			af_rlock_keys + sk->sk_family,
1997			af_family_rlock_key_strings[sk->sk_family]);
1998	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1999			af_wlock_keys + sk->sk_family,
2000			af_family_wlock_key_strings[sk->sk_family]);
2001	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2002			af_elock_keys + sk->sk_family,
2003			af_family_elock_key_strings[sk->sk_family]);
2004	lockdep_set_class_and_name(&sk->sk_callback_lock,
2005			af_callback_keys + sk->sk_family,
2006			af_family_clock_key_strings[sk->sk_family]);
2007}
2008
2009/**
2010 *	sk_clone_lock - clone a socket, and lock its clone
2011 *	@sk: the socket to clone
2012 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2013 *
2014 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2015 */
2016struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2017{
2018	struct proto *prot = READ_ONCE(sk->sk_prot);
2019	struct sk_filter *filter;
2020	bool is_charged = true;
2021	struct sock *newsk;
2022
2023	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2024	if (!newsk)
2025		goto out;
2026
2027	sock_copy(newsk, sk);
2028
2029	newsk->sk_prot_creator = prot;
2030
2031	/* SANITY */
2032	if (likely(newsk->sk_net_refcnt))
2033		get_net(sock_net(newsk));
 
 
 
 
 
 
 
 
 
 
2034	sk_node_init(&newsk->sk_node);
2035	sock_lock_init(newsk);
2036	bh_lock_sock(newsk);
2037	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2038	newsk->sk_backlog.len = 0;
2039
2040	atomic_set(&newsk->sk_rmem_alloc, 0);
2041
2042	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2043	refcount_set(&newsk->sk_wmem_alloc, 1);
2044
2045	atomic_set(&newsk->sk_omem_alloc, 0);
2046	sk_init_common(newsk);
2047
2048	newsk->sk_dst_cache	= NULL;
2049	newsk->sk_dst_pending_confirm = 0;
2050	newsk->sk_wmem_queued	= 0;
2051	newsk->sk_forward_alloc = 0;
 
2052	atomic_set(&newsk->sk_drops, 0);
2053	newsk->sk_send_head	= NULL;
2054	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2055	atomic_set(&newsk->sk_zckey, 0);
2056
2057	sock_reset_flag(newsk, SOCK_DONE);
2058
2059	/* sk->sk_memcg will be populated at accept() time */
2060	newsk->sk_memcg = NULL;
2061
2062	cgroup_sk_clone(&newsk->sk_cgrp_data);
2063
2064	rcu_read_lock();
2065	filter = rcu_dereference(sk->sk_filter);
2066	if (filter != NULL)
2067		/* though it's an empty new sock, the charging may fail
2068		 * if sysctl_optmem_max was changed between creation of
2069		 * original socket and cloning
2070		 */
2071		is_charged = sk_filter_charge(newsk, filter);
2072	RCU_INIT_POINTER(newsk->sk_filter, filter);
2073	rcu_read_unlock();
2074
2075	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2076		/* We need to make sure that we don't uncharge the new
2077		 * socket if we couldn't charge it in the first place
2078		 * as otherwise we uncharge the parent's filter.
2079		 */
2080		if (!is_charged)
2081			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2082		sk_free_unlock_clone(newsk);
2083		newsk = NULL;
2084		goto out;
2085	}
2086	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2087
2088	if (bpf_sk_storage_clone(sk, newsk)) {
2089		sk_free_unlock_clone(newsk);
2090		newsk = NULL;
2091		goto out;
2092	}
2093
2094	/* Clear sk_user_data if parent had the pointer tagged
2095	 * as not suitable for copying when cloning.
2096	 */
2097	if (sk_user_data_is_nocopy(newsk))
2098		newsk->sk_user_data = NULL;
2099
2100	newsk->sk_err	   = 0;
2101	newsk->sk_err_soft = 0;
2102	newsk->sk_priority = 0;
2103	newsk->sk_incoming_cpu = raw_smp_processor_id();
2104	if (likely(newsk->sk_net_refcnt))
2105		sock_inuse_add(sock_net(newsk), 1);
2106
2107	/* Before updating sk_refcnt, we must commit prior changes to memory
2108	 * (Documentation/RCU/rculist_nulls.rst for details)
2109	 */
2110	smp_wmb();
2111	refcount_set(&newsk->sk_refcnt, 2);
2112
2113	/* Increment the counter in the same struct proto as the master
2114	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2115	 * is the same as sk->sk_prot->socks, as this field was copied
2116	 * with memcpy).
2117	 *
2118	 * This _changes_ the previous behaviour, where
2119	 * tcp_create_openreq_child always was incrementing the
2120	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2121	 * to be taken into account in all callers. -acme
2122	 */
2123	sk_refcnt_debug_inc(newsk);
2124	sk_set_socket(newsk, NULL);
2125	sk_tx_queue_clear(newsk);
2126	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2127
2128	if (newsk->sk_prot->sockets_allocated)
2129		sk_sockets_allocated_inc(newsk);
2130
2131	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2132		net_enable_timestamp();
2133out:
2134	return newsk;
2135}
2136EXPORT_SYMBOL_GPL(sk_clone_lock);
2137
2138void sk_free_unlock_clone(struct sock *sk)
2139{
2140	/* It is still raw copy of parent, so invalidate
2141	 * destructor and make plain sk_free() */
2142	sk->sk_destruct = NULL;
2143	bh_unlock_sock(sk);
2144	sk_free(sk);
2145}
2146EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2147
 
 
 
 
 
 
 
 
 
 
 
 
 
2148void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2149{
2150	u32 max_segs = 1;
2151
2152	sk_dst_set(sk, dst);
2153	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
 
 
2154	if (sk->sk_route_caps & NETIF_F_GSO)
2155		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2156	sk->sk_route_caps &= ~sk->sk_route_nocaps;
 
2157	if (sk_can_gso(sk)) {
2158		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2159			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2160		} else {
2161			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2162			sk->sk_gso_max_size = dst->dev->gso_max_size;
2163			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
 
 
 
 
2164		}
2165	}
2166	sk->sk_gso_max_segs = max_segs;
2167}
2168EXPORT_SYMBOL_GPL(sk_setup_caps);
2169
2170/*
2171 *	Simple resource managers for sockets.
2172 */
2173
2174
2175/*
2176 * Write buffer destructor automatically called from kfree_skb.
2177 */
2178void sock_wfree(struct sk_buff *skb)
2179{
2180	struct sock *sk = skb->sk;
2181	unsigned int len = skb->truesize;
 
2182
2183	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
 
 
 
 
 
 
 
 
 
 
 
2184		/*
2185		 * Keep a reference on sk_wmem_alloc, this will be released
2186		 * after sk_write_space() call
2187		 */
2188		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2189		sk->sk_write_space(sk);
2190		len = 1;
2191	}
2192	/*
2193	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2194	 * could not do because of in-flight packets
2195	 */
2196	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2197		__sk_free(sk);
2198}
2199EXPORT_SYMBOL(sock_wfree);
2200
2201/* This variant of sock_wfree() is used by TCP,
2202 * since it sets SOCK_USE_WRITE_QUEUE.
2203 */
2204void __sock_wfree(struct sk_buff *skb)
2205{
2206	struct sock *sk = skb->sk;
2207
2208	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2209		__sk_free(sk);
2210}
2211
2212void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2213{
2214	skb_orphan(skb);
2215	skb->sk = sk;
2216#ifdef CONFIG_INET
2217	if (unlikely(!sk_fullsock(sk))) {
2218		skb->destructor = sock_edemux;
2219		sock_hold(sk);
2220		return;
2221	}
2222#endif
2223	skb->destructor = sock_wfree;
2224	skb_set_hash_from_sk(skb, sk);
2225	/*
2226	 * We used to take a refcount on sk, but following operation
2227	 * is enough to guarantee sk_free() wont free this sock until
2228	 * all in-flight packets are completed
2229	 */
2230	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2231}
2232EXPORT_SYMBOL(skb_set_owner_w);
2233
2234static bool can_skb_orphan_partial(const struct sk_buff *skb)
2235{
2236#ifdef CONFIG_TLS_DEVICE
2237	/* Drivers depend on in-order delivery for crypto offload,
2238	 * partial orphan breaks out-of-order-OK logic.
2239	 */
2240	if (skb->decrypted)
2241		return false;
2242#endif
2243	return (skb->destructor == sock_wfree ||
2244		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2245}
2246
2247/* This helper is used by netem, as it can hold packets in its
2248 * delay queue. We want to allow the owner socket to send more
2249 * packets, as if they were already TX completed by a typical driver.
2250 * But we also want to keep skb->sk set because some packet schedulers
2251 * rely on it (sch_fq for example).
2252 */
2253void skb_orphan_partial(struct sk_buff *skb)
2254{
2255	if (skb_is_tcp_pure_ack(skb))
2256		return;
2257
2258	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2259		return;
2260
2261	skb_orphan(skb);
2262}
2263EXPORT_SYMBOL(skb_orphan_partial);
2264
2265/*
2266 * Read buffer destructor automatically called from kfree_skb.
2267 */
2268void sock_rfree(struct sk_buff *skb)
2269{
2270	struct sock *sk = skb->sk;
2271	unsigned int len = skb->truesize;
2272
2273	atomic_sub(len, &sk->sk_rmem_alloc);
2274	sk_mem_uncharge(sk, len);
2275}
2276EXPORT_SYMBOL(sock_rfree);
2277
2278/*
2279 * Buffer destructor for skbs that are not used directly in read or write
2280 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2281 */
2282void sock_efree(struct sk_buff *skb)
2283{
2284	sock_put(skb->sk);
2285}
2286EXPORT_SYMBOL(sock_efree);
2287
2288/* Buffer destructor for prefetch/receive path where reference count may
2289 * not be held, e.g. for listen sockets.
2290 */
2291#ifdef CONFIG_INET
2292void sock_pfree(struct sk_buff *skb)
2293{
2294	if (sk_is_refcounted(skb->sk))
2295		sock_gen_put(skb->sk);
2296}
2297EXPORT_SYMBOL(sock_pfree);
2298#endif /* CONFIG_INET */
2299
2300kuid_t sock_i_uid(struct sock *sk)
2301{
2302	kuid_t uid;
2303
2304	read_lock_bh(&sk->sk_callback_lock);
2305	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2306	read_unlock_bh(&sk->sk_callback_lock);
2307	return uid;
2308}
2309EXPORT_SYMBOL(sock_i_uid);
2310
2311unsigned long sock_i_ino(struct sock *sk)
2312{
2313	unsigned long ino;
2314
2315	read_lock_bh(&sk->sk_callback_lock);
2316	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2317	read_unlock_bh(&sk->sk_callback_lock);
2318	return ino;
2319}
2320EXPORT_SYMBOL(sock_i_ino);
2321
2322/*
2323 * Allocate a skb from the socket's send buffer.
2324 */
2325struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2326			     gfp_t priority)
2327{
2328	if (force ||
2329	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2330		struct sk_buff *skb = alloc_skb(size, priority);
2331
2332		if (skb) {
2333			skb_set_owner_w(skb, sk);
2334			return skb;
2335		}
2336	}
2337	return NULL;
2338}
2339EXPORT_SYMBOL(sock_wmalloc);
2340
2341static void sock_ofree(struct sk_buff *skb)
2342{
2343	struct sock *sk = skb->sk;
2344
2345	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2346}
2347
2348struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2349			     gfp_t priority)
2350{
2351	struct sk_buff *skb;
2352
2353	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2354	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2355	    sysctl_optmem_max)
2356		return NULL;
2357
2358	skb = alloc_skb(size, priority);
2359	if (!skb)
2360		return NULL;
2361
2362	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2363	skb->sk = sk;
2364	skb->destructor = sock_ofree;
2365	return skb;
2366}
2367
2368/*
2369 * Allocate a memory block from the socket's option memory buffer.
2370 */
2371void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2372{
2373	if ((unsigned int)size <= sysctl_optmem_max &&
2374	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
 
 
2375		void *mem;
2376		/* First do the add, to avoid the race if kmalloc
2377		 * might sleep.
2378		 */
2379		atomic_add(size, &sk->sk_omem_alloc);
2380		mem = kmalloc(size, priority);
2381		if (mem)
2382			return mem;
2383		atomic_sub(size, &sk->sk_omem_alloc);
2384	}
2385	return NULL;
2386}
2387EXPORT_SYMBOL(sock_kmalloc);
2388
2389/* Free an option memory block. Note, we actually want the inline
2390 * here as this allows gcc to detect the nullify and fold away the
2391 * condition entirely.
2392 */
2393static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2394				  const bool nullify)
2395{
2396	if (WARN_ON_ONCE(!mem))
2397		return;
2398	if (nullify)
2399		kfree_sensitive(mem);
2400	else
2401		kfree(mem);
2402	atomic_sub(size, &sk->sk_omem_alloc);
2403}
2404
2405void sock_kfree_s(struct sock *sk, void *mem, int size)
2406{
2407	__sock_kfree_s(sk, mem, size, false);
2408}
2409EXPORT_SYMBOL(sock_kfree_s);
2410
2411void sock_kzfree_s(struct sock *sk, void *mem, int size)
2412{
2413	__sock_kfree_s(sk, mem, size, true);
2414}
2415EXPORT_SYMBOL(sock_kzfree_s);
2416
2417/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2418   I think, these locks should be removed for datagram sockets.
2419 */
2420static long sock_wait_for_wmem(struct sock *sk, long timeo)
2421{
2422	DEFINE_WAIT(wait);
2423
2424	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2425	for (;;) {
2426		if (!timeo)
2427			break;
2428		if (signal_pending(current))
2429			break;
2430		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2431		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2432		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2433			break;
2434		if (sk->sk_shutdown & SEND_SHUTDOWN)
2435			break;
2436		if (sk->sk_err)
2437			break;
2438		timeo = schedule_timeout(timeo);
2439	}
2440	finish_wait(sk_sleep(sk), &wait);
2441	return timeo;
2442}
2443
2444
2445/*
2446 *	Generic send/receive buffer handlers
2447 */
2448
2449struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2450				     unsigned long data_len, int noblock,
2451				     int *errcode, int max_page_order)
2452{
2453	struct sk_buff *skb;
2454	long timeo;
2455	int err;
2456
2457	timeo = sock_sndtimeo(sk, noblock);
2458	for (;;) {
2459		err = sock_error(sk);
2460		if (err != 0)
2461			goto failure;
2462
2463		err = -EPIPE;
2464		if (sk->sk_shutdown & SEND_SHUTDOWN)
2465			goto failure;
2466
2467		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2468			break;
2469
2470		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2471		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2472		err = -EAGAIN;
2473		if (!timeo)
2474			goto failure;
2475		if (signal_pending(current))
2476			goto interrupted;
2477		timeo = sock_wait_for_wmem(sk, timeo);
2478	}
2479	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2480				   errcode, sk->sk_allocation);
2481	if (skb)
2482		skb_set_owner_w(skb, sk);
2483	return skb;
2484
2485interrupted:
2486	err = sock_intr_errno(timeo);
2487failure:
2488	*errcode = err;
2489	return NULL;
2490}
2491EXPORT_SYMBOL(sock_alloc_send_pskb);
2492
2493struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2494				    int noblock, int *errcode)
2495{
2496	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2497}
2498EXPORT_SYMBOL(sock_alloc_send_skb);
2499
2500int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2501		     struct sockcm_cookie *sockc)
2502{
2503	u32 tsflags;
2504
2505	switch (cmsg->cmsg_type) {
2506	case SO_MARK:
2507		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 
2508			return -EPERM;
2509		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2510			return -EINVAL;
2511		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2512		break;
2513	case SO_TIMESTAMPING_OLD:
2514		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2515			return -EINVAL;
2516
2517		tsflags = *(u32 *)CMSG_DATA(cmsg);
2518		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2519			return -EINVAL;
2520
2521		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2522		sockc->tsflags |= tsflags;
2523		break;
2524	case SCM_TXTIME:
2525		if (!sock_flag(sk, SOCK_TXTIME))
2526			return -EINVAL;
2527		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2528			return -EINVAL;
2529		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2530		break;
2531	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2532	case SCM_RIGHTS:
2533	case SCM_CREDENTIALS:
2534		break;
2535	default:
2536		return -EINVAL;
2537	}
2538	return 0;
2539}
2540EXPORT_SYMBOL(__sock_cmsg_send);
2541
2542int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2543		   struct sockcm_cookie *sockc)
2544{
2545	struct cmsghdr *cmsg;
2546	int ret;
2547
2548	for_each_cmsghdr(cmsg, msg) {
2549		if (!CMSG_OK(msg, cmsg))
2550			return -EINVAL;
2551		if (cmsg->cmsg_level != SOL_SOCKET)
2552			continue;
2553		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2554		if (ret)
2555			return ret;
2556	}
2557	return 0;
2558}
2559EXPORT_SYMBOL(sock_cmsg_send);
2560
2561static void sk_enter_memory_pressure(struct sock *sk)
2562{
2563	if (!sk->sk_prot->enter_memory_pressure)
2564		return;
2565
2566	sk->sk_prot->enter_memory_pressure(sk);
2567}
2568
2569static void sk_leave_memory_pressure(struct sock *sk)
2570{
2571	if (sk->sk_prot->leave_memory_pressure) {
2572		sk->sk_prot->leave_memory_pressure(sk);
2573	} else {
2574		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2575
2576		if (memory_pressure && READ_ONCE(*memory_pressure))
2577			WRITE_ONCE(*memory_pressure, 0);
2578	}
2579}
2580
2581#define SKB_FRAG_PAGE_ORDER	get_order(32768)
2582DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2583
2584/**
2585 * skb_page_frag_refill - check that a page_frag contains enough room
2586 * @sz: minimum size of the fragment we want to get
2587 * @pfrag: pointer to page_frag
2588 * @gfp: priority for memory allocation
2589 *
2590 * Note: While this allocator tries to use high order pages, there is
2591 * no guarantee that allocations succeed. Therefore, @sz MUST be
2592 * less or equal than PAGE_SIZE.
2593 */
2594bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2595{
2596	if (pfrag->page) {
2597		if (page_ref_count(pfrag->page) == 1) {
2598			pfrag->offset = 0;
2599			return true;
2600		}
2601		if (pfrag->offset + sz <= pfrag->size)
2602			return true;
2603		put_page(pfrag->page);
2604	}
2605
2606	pfrag->offset = 0;
2607	if (SKB_FRAG_PAGE_ORDER &&
2608	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2609		/* Avoid direct reclaim but allow kswapd to wake */
2610		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2611					  __GFP_COMP | __GFP_NOWARN |
2612					  __GFP_NORETRY,
2613					  SKB_FRAG_PAGE_ORDER);
2614		if (likely(pfrag->page)) {
2615			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2616			return true;
2617		}
2618	}
2619	pfrag->page = alloc_page(gfp);
2620	if (likely(pfrag->page)) {
2621		pfrag->size = PAGE_SIZE;
2622		return true;
2623	}
2624	return false;
2625}
2626EXPORT_SYMBOL(skb_page_frag_refill);
2627
2628bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2629{
2630	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2631		return true;
2632
2633	sk_enter_memory_pressure(sk);
2634	sk_stream_moderate_sndbuf(sk);
2635	return false;
2636}
2637EXPORT_SYMBOL(sk_page_frag_refill);
2638
2639void __lock_sock(struct sock *sk)
2640	__releases(&sk->sk_lock.slock)
2641	__acquires(&sk->sk_lock.slock)
2642{
2643	DEFINE_WAIT(wait);
2644
2645	for (;;) {
2646		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2647					TASK_UNINTERRUPTIBLE);
2648		spin_unlock_bh(&sk->sk_lock.slock);
2649		schedule();
2650		spin_lock_bh(&sk->sk_lock.slock);
2651		if (!sock_owned_by_user(sk))
2652			break;
2653	}
2654	finish_wait(&sk->sk_lock.wq, &wait);
2655}
2656
2657void __release_sock(struct sock *sk)
2658	__releases(&sk->sk_lock.slock)
2659	__acquires(&sk->sk_lock.slock)
2660{
2661	struct sk_buff *skb, *next;
2662
2663	while ((skb = sk->sk_backlog.head) != NULL) {
2664		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2665
2666		spin_unlock_bh(&sk->sk_lock.slock);
2667
2668		do {
2669			next = skb->next;
2670			prefetch(next);
2671			WARN_ON_ONCE(skb_dst_is_noref(skb));
2672			skb_mark_not_on_list(skb);
2673			sk_backlog_rcv(sk, skb);
2674
2675			cond_resched();
2676
2677			skb = next;
2678		} while (skb != NULL);
2679
2680		spin_lock_bh(&sk->sk_lock.slock);
2681	}
2682
2683	/*
2684	 * Doing the zeroing here guarantee we can not loop forever
2685	 * while a wild producer attempts to flood us.
2686	 */
2687	sk->sk_backlog.len = 0;
2688}
2689
2690void __sk_flush_backlog(struct sock *sk)
2691{
2692	spin_lock_bh(&sk->sk_lock.slock);
2693	__release_sock(sk);
2694	spin_unlock_bh(&sk->sk_lock.slock);
2695}
 
2696
2697/**
2698 * sk_wait_data - wait for data to arrive at sk_receive_queue
2699 * @sk:    sock to wait on
2700 * @timeo: for how long
2701 * @skb:   last skb seen on sk_receive_queue
2702 *
2703 * Now socket state including sk->sk_err is changed only under lock,
2704 * hence we may omit checks after joining wait queue.
2705 * We check receive queue before schedule() only as optimization;
2706 * it is very likely that release_sock() added new data.
2707 */
2708int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2709{
2710	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2711	int rc;
2712
2713	add_wait_queue(sk_sleep(sk), &wait);
2714	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2715	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2716	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2717	remove_wait_queue(sk_sleep(sk), &wait);
2718	return rc;
2719}
2720EXPORT_SYMBOL(sk_wait_data);
2721
2722/**
2723 *	__sk_mem_raise_allocated - increase memory_allocated
2724 *	@sk: socket
2725 *	@size: memory size to allocate
2726 *	@amt: pages to allocate
2727 *	@kind: allocation type
2728 *
2729 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2730 */
2731int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2732{
 
2733	struct proto *prot = sk->sk_prot;
2734	long allocated = sk_memory_allocated_add(sk, amt);
2735	bool charged = true;
 
2736
2737	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2738	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
 
 
 
2739		goto suppress_allocation;
2740
2741	/* Under limit. */
2742	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2743		sk_leave_memory_pressure(sk);
2744		return 1;
2745	}
2746
2747	/* Under pressure. */
2748	if (allocated > sk_prot_mem_limits(sk, 1))
2749		sk_enter_memory_pressure(sk);
2750
2751	/* Over hard limit. */
2752	if (allocated > sk_prot_mem_limits(sk, 2))
2753		goto suppress_allocation;
2754
2755	/* guarantee minimum buffer size under pressure */
2756	if (kind == SK_MEM_RECV) {
2757		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2758			return 1;
2759
2760	} else { /* SK_MEM_SEND */
2761		int wmem0 = sk_get_wmem0(sk, prot);
2762
2763		if (sk->sk_type == SOCK_STREAM) {
2764			if (sk->sk_wmem_queued < wmem0)
2765				return 1;
2766		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2767				return 1;
2768		}
2769	}
2770
2771	if (sk_has_memory_pressure(sk)) {
2772		u64 alloc;
2773
2774		if (!sk_under_memory_pressure(sk))
2775			return 1;
2776		alloc = sk_sockets_allocated_read_positive(sk);
2777		if (sk_prot_mem_limits(sk, 2) > alloc *
2778		    sk_mem_pages(sk->sk_wmem_queued +
2779				 atomic_read(&sk->sk_rmem_alloc) +
2780				 sk->sk_forward_alloc))
2781			return 1;
2782	}
2783
2784suppress_allocation:
2785
2786	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2787		sk_stream_moderate_sndbuf(sk);
2788
2789		/* Fail only if socket is _under_ its sndbuf.
2790		 * In this case we cannot block, so that we have to fail.
2791		 */
2792		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
 
 
 
 
 
2793			return 1;
 
2794	}
2795
2796	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2797		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2798
2799	sk_memory_allocated_sub(sk, amt);
2800
2801	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2802		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2803
2804	return 0;
2805}
2806EXPORT_SYMBOL(__sk_mem_raise_allocated);
2807
2808/**
2809 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2810 *	@sk: socket
2811 *	@size: memory size to allocate
2812 *	@kind: allocation type
2813 *
2814 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2815 *	rmem allocation. This function assumes that protocols which have
2816 *	memory_pressure use sk_wmem_queued as write buffer accounting.
2817 */
2818int __sk_mem_schedule(struct sock *sk, int size, int kind)
2819{
2820	int ret, amt = sk_mem_pages(size);
2821
2822	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2823	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2824	if (!ret)
2825		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2826	return ret;
2827}
2828EXPORT_SYMBOL(__sk_mem_schedule);
2829
2830/**
2831 *	__sk_mem_reduce_allocated - reclaim memory_allocated
2832 *	@sk: socket
2833 *	@amount: number of quanta
2834 *
2835 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2836 */
2837void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2838{
2839	sk_memory_allocated_sub(sk, amount);
2840
2841	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2842		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2843
2844	if (sk_under_memory_pressure(sk) &&
2845	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2846		sk_leave_memory_pressure(sk);
2847}
2848EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2849
2850/**
2851 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2852 *	@sk: socket
2853 *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2854 */
2855void __sk_mem_reclaim(struct sock *sk, int amount)
2856{
2857	amount >>= SK_MEM_QUANTUM_SHIFT;
2858	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2859	__sk_mem_reduce_allocated(sk, amount);
2860}
2861EXPORT_SYMBOL(__sk_mem_reclaim);
2862
2863int sk_set_peek_off(struct sock *sk, int val)
2864{
2865	sk->sk_peek_off = val;
2866	return 0;
2867}
2868EXPORT_SYMBOL_GPL(sk_set_peek_off);
2869
2870/*
2871 * Set of default routines for initialising struct proto_ops when
2872 * the protocol does not support a particular function. In certain
2873 * cases where it makes no sense for a protocol to have a "do nothing"
2874 * function, some default processing is provided.
2875 */
2876
2877int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2878{
2879	return -EOPNOTSUPP;
2880}
2881EXPORT_SYMBOL(sock_no_bind);
2882
2883int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2884		    int len, int flags)
2885{
2886	return -EOPNOTSUPP;
2887}
2888EXPORT_SYMBOL(sock_no_connect);
2889
2890int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2891{
2892	return -EOPNOTSUPP;
2893}
2894EXPORT_SYMBOL(sock_no_socketpair);
2895
2896int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2897		   bool kern)
2898{
2899	return -EOPNOTSUPP;
2900}
2901EXPORT_SYMBOL(sock_no_accept);
2902
2903int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2904		    int peer)
2905{
2906	return -EOPNOTSUPP;
2907}
2908EXPORT_SYMBOL(sock_no_getname);
2909
2910int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2911{
2912	return -EOPNOTSUPP;
2913}
2914EXPORT_SYMBOL(sock_no_ioctl);
2915
2916int sock_no_listen(struct socket *sock, int backlog)
2917{
2918	return -EOPNOTSUPP;
2919}
2920EXPORT_SYMBOL(sock_no_listen);
2921
2922int sock_no_shutdown(struct socket *sock, int how)
2923{
2924	return -EOPNOTSUPP;
2925}
2926EXPORT_SYMBOL(sock_no_shutdown);
2927
2928int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2929{
2930	return -EOPNOTSUPP;
2931}
2932EXPORT_SYMBOL(sock_no_sendmsg);
2933
2934int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2935{
2936	return -EOPNOTSUPP;
2937}
2938EXPORT_SYMBOL(sock_no_sendmsg_locked);
2939
2940int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2941		    int flags)
2942{
2943	return -EOPNOTSUPP;
2944}
2945EXPORT_SYMBOL(sock_no_recvmsg);
2946
2947int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2948{
2949	/* Mirror missing mmap method error code */
2950	return -ENODEV;
2951}
2952EXPORT_SYMBOL(sock_no_mmap);
2953
2954/*
2955 * When a file is received (via SCM_RIGHTS, etc), we must bump the
2956 * various sock-based usage counts.
2957 */
2958void __receive_sock(struct file *file)
2959{
2960	struct socket *sock;
2961
2962	sock = sock_from_file(file);
2963	if (sock) {
2964		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
2965		sock_update_classid(&sock->sk->sk_cgrp_data);
2966	}
2967}
2968
2969ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2970{
2971	ssize_t res;
2972	struct msghdr msg = {.msg_flags = flags};
2973	struct kvec iov;
2974	char *kaddr = kmap(page);
2975	iov.iov_base = kaddr + offset;
2976	iov.iov_len = size;
2977	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2978	kunmap(page);
2979	return res;
2980}
2981EXPORT_SYMBOL(sock_no_sendpage);
2982
2983ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2984				int offset, size_t size, int flags)
2985{
2986	ssize_t res;
2987	struct msghdr msg = {.msg_flags = flags};
2988	struct kvec iov;
2989	char *kaddr = kmap(page);
2990
2991	iov.iov_base = kaddr + offset;
2992	iov.iov_len = size;
2993	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2994	kunmap(page);
2995	return res;
2996}
2997EXPORT_SYMBOL(sock_no_sendpage_locked);
2998
2999/*
3000 *	Default Socket Callbacks
3001 */
3002
3003static void sock_def_wakeup(struct sock *sk)
3004{
3005	struct socket_wq *wq;
3006
3007	rcu_read_lock();
3008	wq = rcu_dereference(sk->sk_wq);
3009	if (skwq_has_sleeper(wq))
3010		wake_up_interruptible_all(&wq->wait);
3011	rcu_read_unlock();
3012}
3013
3014static void sock_def_error_report(struct sock *sk)
3015{
3016	struct socket_wq *wq;
3017
3018	rcu_read_lock();
3019	wq = rcu_dereference(sk->sk_wq);
3020	if (skwq_has_sleeper(wq))
3021		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3022	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3023	rcu_read_unlock();
3024}
3025
3026void sock_def_readable(struct sock *sk)
3027{
3028	struct socket_wq *wq;
3029
3030	rcu_read_lock();
3031	wq = rcu_dereference(sk->sk_wq);
3032	if (skwq_has_sleeper(wq))
3033		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3034						EPOLLRDNORM | EPOLLRDBAND);
3035	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3036	rcu_read_unlock();
3037}
3038
3039static void sock_def_write_space(struct sock *sk)
3040{
3041	struct socket_wq *wq;
3042
3043	rcu_read_lock();
3044
3045	/* Do not wake up a writer until he can make "significant"
3046	 * progress.  --DaveM
3047	 */
3048	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) {
3049		wq = rcu_dereference(sk->sk_wq);
3050		if (skwq_has_sleeper(wq))
3051			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3052						EPOLLWRNORM | EPOLLWRBAND);
3053
3054		/* Should agree with poll, otherwise some programs break */
3055		if (sock_writeable(sk))
3056			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3057	}
3058
3059	rcu_read_unlock();
3060}
3061
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3062static void sock_def_destruct(struct sock *sk)
3063{
3064}
3065
3066void sk_send_sigurg(struct sock *sk)
3067{
3068	if (sk->sk_socket && sk->sk_socket->file)
3069		if (send_sigurg(&sk->sk_socket->file->f_owner))
3070			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3071}
3072EXPORT_SYMBOL(sk_send_sigurg);
3073
3074void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3075		    unsigned long expires)
3076{
3077	if (!mod_timer(timer, expires))
3078		sock_hold(sk);
3079}
3080EXPORT_SYMBOL(sk_reset_timer);
3081
3082void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3083{
3084	if (del_timer(timer))
3085		__sock_put(sk);
3086}
3087EXPORT_SYMBOL(sk_stop_timer);
3088
3089void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3090{
3091	if (del_timer_sync(timer))
3092		__sock_put(sk);
3093}
3094EXPORT_SYMBOL(sk_stop_timer_sync);
3095
3096void sock_init_data(struct socket *sock, struct sock *sk)
3097{
3098	sk_init_common(sk);
3099	sk->sk_send_head	=	NULL;
3100
3101	timer_setup(&sk->sk_timer, NULL, 0);
3102
3103	sk->sk_allocation	=	GFP_KERNEL;
3104	sk->sk_rcvbuf		=	sysctl_rmem_default;
3105	sk->sk_sndbuf		=	sysctl_wmem_default;
3106	sk->sk_state		=	TCP_CLOSE;
 
3107	sk_set_socket(sk, sock);
3108
3109	sock_set_flag(sk, SOCK_ZAPPED);
3110
3111	if (sock) {
3112		sk->sk_type	=	sock->type;
3113		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3114		sock->sk	=	sk;
3115		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3116	} else {
3117		RCU_INIT_POINTER(sk->sk_wq, NULL);
3118		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3119	}
3120
3121	rwlock_init(&sk->sk_callback_lock);
3122	if (sk->sk_kern_sock)
3123		lockdep_set_class_and_name(
3124			&sk->sk_callback_lock,
3125			af_kern_callback_keys + sk->sk_family,
3126			af_family_kern_clock_key_strings[sk->sk_family]);
3127	else
3128		lockdep_set_class_and_name(
3129			&sk->sk_callback_lock,
3130			af_callback_keys + sk->sk_family,
3131			af_family_clock_key_strings[sk->sk_family]);
3132
3133	sk->sk_state_change	=	sock_def_wakeup;
3134	sk->sk_data_ready	=	sock_def_readable;
3135	sk->sk_write_space	=	sock_def_write_space;
3136	sk->sk_error_report	=	sock_def_error_report;
3137	sk->sk_destruct		=	sock_def_destruct;
3138
3139	sk->sk_frag.page	=	NULL;
3140	sk->sk_frag.offset	=	0;
3141	sk->sk_peek_off		=	-1;
3142
3143	sk->sk_peer_pid 	=	NULL;
3144	sk->sk_peer_cred	=	NULL;
3145	spin_lock_init(&sk->sk_peer_lock);
3146
3147	sk->sk_write_pending	=	0;
3148	sk->sk_rcvlowat		=	1;
3149	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3150	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3151
3152	sk->sk_stamp = SK_DEFAULT_STAMP;
3153#if BITS_PER_LONG==32
3154	seqlock_init(&sk->sk_stamp_seq);
3155#endif
3156	atomic_set(&sk->sk_zckey, 0);
3157
3158#ifdef CONFIG_NET_RX_BUSY_POLL
3159	sk->sk_napi_id		=	0;
3160	sk->sk_ll_usec		=	sysctl_net_busy_read;
3161#endif
3162
3163	sk->sk_max_pacing_rate = ~0UL;
3164	sk->sk_pacing_rate = ~0UL;
3165	WRITE_ONCE(sk->sk_pacing_shift, 10);
3166	sk->sk_incoming_cpu = -1;
3167
3168	sk_rx_queue_clear(sk);
3169	/*
3170	 * Before updating sk_refcnt, we must commit prior changes to memory
3171	 * (Documentation/RCU/rculist_nulls.rst for details)
3172	 */
3173	smp_wmb();
3174	refcount_set(&sk->sk_refcnt, 1);
3175	atomic_set(&sk->sk_drops, 0);
3176}
3177EXPORT_SYMBOL(sock_init_data);
3178
3179void lock_sock_nested(struct sock *sk, int subclass)
3180{
 
 
 
3181	might_sleep();
3182	spin_lock_bh(&sk->sk_lock.slock);
3183	if (sk->sk_lock.owned)
3184		__lock_sock(sk);
3185	sk->sk_lock.owned = 1;
3186	spin_unlock(&sk->sk_lock.slock);
3187	/*
3188	 * The sk_lock has mutex_lock() semantics here:
3189	 */
3190	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3191	local_bh_enable();
3192}
3193EXPORT_SYMBOL(lock_sock_nested);
3194
3195void release_sock(struct sock *sk)
3196{
3197	spin_lock_bh(&sk->sk_lock.slock);
3198	if (sk->sk_backlog.tail)
3199		__release_sock(sk);
3200
3201	/* Warning : release_cb() might need to release sk ownership,
3202	 * ie call sock_release_ownership(sk) before us.
3203	 */
3204	if (sk->sk_prot->release_cb)
3205		sk->sk_prot->release_cb(sk);
3206
3207	sock_release_ownership(sk);
3208	if (waitqueue_active(&sk->sk_lock.wq))
3209		wake_up(&sk->sk_lock.wq);
3210	spin_unlock_bh(&sk->sk_lock.slock);
3211}
3212EXPORT_SYMBOL(release_sock);
3213
3214/**
3215 * lock_sock_fast - fast version of lock_sock
3216 * @sk: socket
3217 *
3218 * This version should be used for very small section, where process wont block
3219 * return false if fast path is taken:
3220 *
3221 *   sk_lock.slock locked, owned = 0, BH disabled
3222 *
3223 * return true if slow path is taken:
3224 *
3225 *   sk_lock.slock unlocked, owned = 1, BH enabled
3226 */
3227bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3228{
3229	might_sleep();
3230	spin_lock_bh(&sk->sk_lock.slock);
3231
3232	if (!sk->sk_lock.owned)
3233		/*
3234		 * Note : We must disable BH
 
 
 
 
 
 
 
 
 
 
 
 
3235		 */
3236		return false;
 
3237
3238	__lock_sock(sk);
3239	sk->sk_lock.owned = 1;
3240	spin_unlock(&sk->sk_lock.slock);
3241	/*
3242	 * The sk_lock has mutex_lock() semantics here:
3243	 */
3244	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
3245	__acquire(&sk->sk_lock.slock);
3246	local_bh_enable();
3247	return true;
3248}
3249EXPORT_SYMBOL(lock_sock_fast);
3250
3251int sock_gettstamp(struct socket *sock, void __user *userstamp,
3252		   bool timeval, bool time32)
3253{
3254	struct sock *sk = sock->sk;
3255	struct timespec64 ts;
3256
3257	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3258	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3259	if (ts.tv_sec == -1)
3260		return -ENOENT;
3261	if (ts.tv_sec == 0) {
3262		ktime_t kt = ktime_get_real();
3263		sock_write_timestamp(sk, kt);
3264		ts = ktime_to_timespec64(kt);
3265	}
3266
3267	if (timeval)
3268		ts.tv_nsec /= 1000;
3269
3270#ifdef CONFIG_COMPAT_32BIT_TIME
3271	if (time32)
3272		return put_old_timespec32(&ts, userstamp);
3273#endif
3274#ifdef CONFIG_SPARC64
3275	/* beware of padding in sparc64 timeval */
3276	if (timeval && !in_compat_syscall()) {
3277		struct __kernel_old_timeval __user tv = {
3278			.tv_sec = ts.tv_sec,
3279			.tv_usec = ts.tv_nsec,
3280		};
3281		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3282			return -EFAULT;
3283		return 0;
3284	}
3285#endif
3286	return put_timespec64(&ts, userstamp);
3287}
3288EXPORT_SYMBOL(sock_gettstamp);
3289
3290void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3291{
3292	if (!sock_flag(sk, flag)) {
3293		unsigned long previous_flags = sk->sk_flags;
3294
3295		sock_set_flag(sk, flag);
3296		/*
3297		 * we just set one of the two flags which require net
3298		 * time stamping, but time stamping might have been on
3299		 * already because of the other one
3300		 */
3301		if (sock_needs_netstamp(sk) &&
3302		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3303			net_enable_timestamp();
3304	}
3305}
3306
3307int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3308		       int level, int type)
3309{
3310	struct sock_exterr_skb *serr;
3311	struct sk_buff *skb;
3312	int copied, err;
3313
3314	err = -EAGAIN;
3315	skb = sock_dequeue_err_skb(sk);
3316	if (skb == NULL)
3317		goto out;
3318
3319	copied = skb->len;
3320	if (copied > len) {
3321		msg->msg_flags |= MSG_TRUNC;
3322		copied = len;
3323	}
3324	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3325	if (err)
3326		goto out_free_skb;
3327
3328	sock_recv_timestamp(msg, sk, skb);
3329
3330	serr = SKB_EXT_ERR(skb);
3331	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3332
3333	msg->msg_flags |= MSG_ERRQUEUE;
3334	err = copied;
3335
3336out_free_skb:
3337	kfree_skb(skb);
3338out:
3339	return err;
3340}
3341EXPORT_SYMBOL(sock_recv_errqueue);
3342
3343/*
3344 *	Get a socket option on an socket.
3345 *
3346 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3347 *	asynchronous errors should be reported by getsockopt. We assume
3348 *	this means if you specify SO_ERROR (otherwise whats the point of it).
3349 */
3350int sock_common_getsockopt(struct socket *sock, int level, int optname,
3351			   char __user *optval, int __user *optlen)
3352{
3353	struct sock *sk = sock->sk;
3354
3355	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
 
3356}
3357EXPORT_SYMBOL(sock_common_getsockopt);
3358
3359int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3360			int flags)
3361{
3362	struct sock *sk = sock->sk;
3363	int addr_len = 0;
3364	int err;
3365
3366	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3367				   flags & ~MSG_DONTWAIT, &addr_len);
3368	if (err >= 0)
3369		msg->msg_namelen = addr_len;
3370	return err;
3371}
3372EXPORT_SYMBOL(sock_common_recvmsg);
3373
3374/*
3375 *	Set socket options on an inet socket.
3376 */
3377int sock_common_setsockopt(struct socket *sock, int level, int optname,
3378			   sockptr_t optval, unsigned int optlen)
3379{
3380	struct sock *sk = sock->sk;
3381
3382	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
 
3383}
3384EXPORT_SYMBOL(sock_common_setsockopt);
3385
3386void sk_common_release(struct sock *sk)
3387{
3388	if (sk->sk_prot->destroy)
3389		sk->sk_prot->destroy(sk);
3390
3391	/*
3392	 * Observation: when sk_common_release is called, processes have
3393	 * no access to socket. But net still has.
3394	 * Step one, detach it from networking:
3395	 *
3396	 * A. Remove from hash tables.
3397	 */
3398
3399	sk->sk_prot->unhash(sk);
3400
3401	/*
3402	 * In this point socket cannot receive new packets, but it is possible
3403	 * that some packets are in flight because some CPU runs receiver and
3404	 * did hash table lookup before we unhashed socket. They will achieve
3405	 * receive queue and will be purged by socket destructor.
3406	 *
3407	 * Also we still have packets pending on receive queue and probably,
3408	 * our own packets waiting in device queues. sock_destroy will drain
3409	 * receive queue, but transmitted packets will delay socket destruction
3410	 * until the last reference will be released.
3411	 */
3412
3413	sock_orphan(sk);
3414
3415	xfrm_sk_free_policy(sk);
3416
3417	sk_refcnt_debug_release(sk);
3418
3419	sock_put(sk);
3420}
3421EXPORT_SYMBOL(sk_common_release);
3422
3423void sk_get_meminfo(const struct sock *sk, u32 *mem)
3424{
3425	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3426
3427	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3428	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3429	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3430	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3431	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3432	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3433	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3434	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3435	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3436}
3437
3438#ifdef CONFIG_PROC_FS
3439#define PROTO_INUSE_NR	64	/* should be enough for the first time */
3440struct prot_inuse {
3441	int val[PROTO_INUSE_NR];
3442};
3443
3444static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3445
3446void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3447{
3448	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3449}
3450EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3451
3452int sock_prot_inuse_get(struct net *net, struct proto *prot)
3453{
3454	int cpu, idx = prot->inuse_idx;
3455	int res = 0;
3456
3457	for_each_possible_cpu(cpu)
3458		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3459
3460	return res >= 0 ? res : 0;
3461}
3462EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3463
3464static void sock_inuse_add(struct net *net, int val)
3465{
3466	this_cpu_add(*net->core.sock_inuse, val);
3467}
3468
3469int sock_inuse_get(struct net *net)
3470{
3471	int cpu, res = 0;
3472
3473	for_each_possible_cpu(cpu)
3474		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3475
3476	return res;
3477}
3478
3479EXPORT_SYMBOL_GPL(sock_inuse_get);
3480
3481static int __net_init sock_inuse_init_net(struct net *net)
3482{
3483	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3484	if (net->core.prot_inuse == NULL)
3485		return -ENOMEM;
3486
3487	net->core.sock_inuse = alloc_percpu(int);
3488	if (net->core.sock_inuse == NULL)
3489		goto out;
3490
3491	return 0;
3492
3493out:
3494	free_percpu(net->core.prot_inuse);
3495	return -ENOMEM;
3496}
3497
3498static void __net_exit sock_inuse_exit_net(struct net *net)
3499{
3500	free_percpu(net->core.prot_inuse);
3501	free_percpu(net->core.sock_inuse);
3502}
3503
3504static struct pernet_operations net_inuse_ops = {
3505	.init = sock_inuse_init_net,
3506	.exit = sock_inuse_exit_net,
3507};
3508
3509static __init int net_inuse_init(void)
3510{
3511	if (register_pernet_subsys(&net_inuse_ops))
3512		panic("Cannot initialize net inuse counters");
3513
3514	return 0;
3515}
3516
3517core_initcall(net_inuse_init);
3518
3519static int assign_proto_idx(struct proto *prot)
3520{
3521	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3522
3523	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3524		pr_err("PROTO_INUSE_NR exhausted\n");
3525		return -ENOSPC;
3526	}
3527
3528	set_bit(prot->inuse_idx, proto_inuse_idx);
3529	return 0;
3530}
3531
3532static void release_proto_idx(struct proto *prot)
3533{
3534	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3535		clear_bit(prot->inuse_idx, proto_inuse_idx);
3536}
3537#else
3538static inline int assign_proto_idx(struct proto *prot)
3539{
3540	return 0;
3541}
3542
3543static inline void release_proto_idx(struct proto *prot)
3544{
3545}
3546
3547static void sock_inuse_add(struct net *net, int val)
3548{
3549}
3550#endif
3551
3552static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3553{
3554	if (!twsk_prot)
3555		return;
3556	kfree(twsk_prot->twsk_slab_name);
3557	twsk_prot->twsk_slab_name = NULL;
3558	kmem_cache_destroy(twsk_prot->twsk_slab);
3559	twsk_prot->twsk_slab = NULL;
3560}
3561
3562static int tw_prot_init(const struct proto *prot)
3563{
3564	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3565
3566	if (!twsk_prot)
3567		return 0;
3568
3569	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3570					      prot->name);
3571	if (!twsk_prot->twsk_slab_name)
3572		return -ENOMEM;
3573
3574	twsk_prot->twsk_slab =
3575		kmem_cache_create(twsk_prot->twsk_slab_name,
3576				  twsk_prot->twsk_obj_size, 0,
3577				  SLAB_ACCOUNT | prot->slab_flags,
3578				  NULL);
3579	if (!twsk_prot->twsk_slab) {
3580		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3581			prot->name);
3582		return -ENOMEM;
3583	}
3584
3585	return 0;
3586}
3587
3588static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3589{
3590	if (!rsk_prot)
3591		return;
3592	kfree(rsk_prot->slab_name);
3593	rsk_prot->slab_name = NULL;
3594	kmem_cache_destroy(rsk_prot->slab);
3595	rsk_prot->slab = NULL;
3596}
3597
3598static int req_prot_init(const struct proto *prot)
3599{
3600	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3601
3602	if (!rsk_prot)
3603		return 0;
3604
3605	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3606					prot->name);
3607	if (!rsk_prot->slab_name)
3608		return -ENOMEM;
3609
3610	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3611					   rsk_prot->obj_size, 0,
3612					   SLAB_ACCOUNT | prot->slab_flags,
3613					   NULL);
3614
3615	if (!rsk_prot->slab) {
3616		pr_crit("%s: Can't create request sock SLAB cache!\n",
3617			prot->name);
3618		return -ENOMEM;
3619	}
3620	return 0;
3621}
3622
3623int proto_register(struct proto *prot, int alloc_slab)
3624{
3625	int ret = -ENOBUFS;
3626
 
 
 
 
 
 
 
 
3627	if (alloc_slab) {
3628		prot->slab = kmem_cache_create_usercopy(prot->name,
3629					prot->obj_size, 0,
3630					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3631					prot->slab_flags,
3632					prot->useroffset, prot->usersize,
3633					NULL);
3634
3635		if (prot->slab == NULL) {
3636			pr_crit("%s: Can't create sock SLAB cache!\n",
3637				prot->name);
3638			goto out;
3639		}
3640
3641		if (req_prot_init(prot))
3642			goto out_free_request_sock_slab;
3643
3644		if (tw_prot_init(prot))
3645			goto out_free_timewait_sock_slab;
3646	}
3647
3648	mutex_lock(&proto_list_mutex);
3649	ret = assign_proto_idx(prot);
3650	if (ret) {
3651		mutex_unlock(&proto_list_mutex);
3652		goto out_free_timewait_sock_slab;
3653	}
3654	list_add(&prot->node, &proto_list);
3655	mutex_unlock(&proto_list_mutex);
3656	return ret;
3657
3658out_free_timewait_sock_slab:
3659	if (alloc_slab)
3660		tw_prot_cleanup(prot->twsk_prot);
3661out_free_request_sock_slab:
3662	if (alloc_slab) {
3663		req_prot_cleanup(prot->rsk_prot);
3664
3665		kmem_cache_destroy(prot->slab);
3666		prot->slab = NULL;
3667	}
3668out:
3669	return ret;
3670}
3671EXPORT_SYMBOL(proto_register);
3672
3673void proto_unregister(struct proto *prot)
3674{
3675	mutex_lock(&proto_list_mutex);
3676	release_proto_idx(prot);
3677	list_del(&prot->node);
3678	mutex_unlock(&proto_list_mutex);
3679
3680	kmem_cache_destroy(prot->slab);
3681	prot->slab = NULL;
3682
3683	req_prot_cleanup(prot->rsk_prot);
3684	tw_prot_cleanup(prot->twsk_prot);
3685}
3686EXPORT_SYMBOL(proto_unregister);
3687
3688int sock_load_diag_module(int family, int protocol)
3689{
3690	if (!protocol) {
3691		if (!sock_is_registered(family))
3692			return -ENOENT;
3693
3694		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3695				      NETLINK_SOCK_DIAG, family);
3696	}
3697
3698#ifdef CONFIG_INET
3699	if (family == AF_INET &&
3700	    protocol != IPPROTO_RAW &&
3701	    protocol < MAX_INET_PROTOS &&
3702	    !rcu_access_pointer(inet_protos[protocol]))
3703		return -ENOENT;
3704#endif
3705
3706	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3707			      NETLINK_SOCK_DIAG, family, protocol);
3708}
3709EXPORT_SYMBOL(sock_load_diag_module);
3710
3711#ifdef CONFIG_PROC_FS
3712static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3713	__acquires(proto_list_mutex)
3714{
3715	mutex_lock(&proto_list_mutex);
3716	return seq_list_start_head(&proto_list, *pos);
3717}
3718
3719static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3720{
3721	return seq_list_next(v, &proto_list, pos);
3722}
3723
3724static void proto_seq_stop(struct seq_file *seq, void *v)
3725	__releases(proto_list_mutex)
3726{
3727	mutex_unlock(&proto_list_mutex);
3728}
3729
3730static char proto_method_implemented(const void *method)
3731{
3732	return method == NULL ? 'n' : 'y';
3733}
3734static long sock_prot_memory_allocated(struct proto *proto)
3735{
3736	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3737}
3738
3739static const char *sock_prot_memory_pressure(struct proto *proto)
3740{
3741	return proto->memory_pressure != NULL ?
3742	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3743}
3744
3745static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3746{
3747
3748	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3749			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3750		   proto->name,
3751		   proto->obj_size,
3752		   sock_prot_inuse_get(seq_file_net(seq), proto),
3753		   sock_prot_memory_allocated(proto),
3754		   sock_prot_memory_pressure(proto),
3755		   proto->max_header,
3756		   proto->slab == NULL ? "no" : "yes",
3757		   module_name(proto->owner),
3758		   proto_method_implemented(proto->close),
3759		   proto_method_implemented(proto->connect),
3760		   proto_method_implemented(proto->disconnect),
3761		   proto_method_implemented(proto->accept),
3762		   proto_method_implemented(proto->ioctl),
3763		   proto_method_implemented(proto->init),
3764		   proto_method_implemented(proto->destroy),
3765		   proto_method_implemented(proto->shutdown),
3766		   proto_method_implemented(proto->setsockopt),
3767		   proto_method_implemented(proto->getsockopt),
3768		   proto_method_implemented(proto->sendmsg),
3769		   proto_method_implemented(proto->recvmsg),
3770		   proto_method_implemented(proto->sendpage),
3771		   proto_method_implemented(proto->bind),
3772		   proto_method_implemented(proto->backlog_rcv),
3773		   proto_method_implemented(proto->hash),
3774		   proto_method_implemented(proto->unhash),
3775		   proto_method_implemented(proto->get_port),
3776		   proto_method_implemented(proto->enter_memory_pressure));
3777}
3778
3779static int proto_seq_show(struct seq_file *seq, void *v)
3780{
3781	if (v == &proto_list)
3782		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3783			   "protocol",
3784			   "size",
3785			   "sockets",
3786			   "memory",
3787			   "press",
3788			   "maxhdr",
3789			   "slab",
3790			   "module",
3791			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3792	else
3793		proto_seq_printf(seq, list_entry(v, struct proto, node));
3794	return 0;
3795}
3796
3797static const struct seq_operations proto_seq_ops = {
3798	.start  = proto_seq_start,
3799	.next   = proto_seq_next,
3800	.stop   = proto_seq_stop,
3801	.show   = proto_seq_show,
3802};
3803
3804static __net_init int proto_init_net(struct net *net)
3805{
3806	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3807			sizeof(struct seq_net_private)))
3808		return -ENOMEM;
3809
3810	return 0;
3811}
3812
3813static __net_exit void proto_exit_net(struct net *net)
3814{
3815	remove_proc_entry("protocols", net->proc_net);
3816}
3817
3818
3819static __net_initdata struct pernet_operations proto_net_ops = {
3820	.init = proto_init_net,
3821	.exit = proto_exit_net,
3822};
3823
3824static int __init proto_init(void)
3825{
3826	return register_pernet_subsys(&proto_net_ops);
3827}
3828
3829subsys_initcall(proto_init);
3830
3831#endif /* PROC_FS */
3832
3833#ifdef CONFIG_NET_RX_BUSY_POLL
3834bool sk_busy_loop_end(void *p, unsigned long start_time)
3835{
3836	struct sock *sk = p;
3837
3838	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
3839	       sk_busy_loop_timeout(sk, start_time);
3840}
3841EXPORT_SYMBOL(sk_busy_loop_end);
3842#endif /* CONFIG_NET_RX_BUSY_POLL */
3843
3844int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
3845{
3846	if (!sk->sk_prot->bind_add)
3847		return -EOPNOTSUPP;
3848	return sk->sk_prot->bind_add(sk, addr, addr_len);
3849}
3850EXPORT_SYMBOL(sock_bind_add);
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);