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v6.13.7
   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 <linux/unaligned.h>
  89#include <linux/capability.h>
  90#include <linux/errno.h>
  91#include <linux/errqueue.h>
  92#include <linux/types.h>
  93#include <linux/socket.h>
  94#include <linux/in.h>
  95#include <linux/kernel.h>
  96#include <linux/module.h>
  97#include <linux/proc_fs.h>
  98#include <linux/seq_file.h>
  99#include <linux/sched.h>
 100#include <linux/sched/mm.h>
 101#include <linux/timer.h>
 102#include <linux/string.h>
 103#include <linux/sockios.h>
 104#include <linux/net.h>
 105#include <linux/mm.h>
 106#include <linux/slab.h>
 107#include <linux/interrupt.h>
 108#include <linux/poll.h>
 109#include <linux/tcp.h>
 110#include <linux/udp.h>
 111#include <linux/init.h>
 112#include <linux/highmem.h>
 113#include <linux/user_namespace.h>
 114#include <linux/static_key.h>
 115#include <linux/memcontrol.h>
 116#include <linux/prefetch.h>
 117#include <linux/compat.h>
 118#include <linux/mroute.h>
 119#include <linux/mroute6.h>
 120#include <linux/icmpv6.h>
 121
 122#include <linux/uaccess.h>
 123
 124#include <linux/netdevice.h>
 125#include <net/protocol.h>
 126#include <linux/skbuff.h>
 127#include <linux/skbuff_ref.h>
 128#include <net/net_namespace.h>
 129#include <net/request_sock.h>
 130#include <net/sock.h>
 131#include <net/proto_memory.h>
 132#include <linux/net_tstamp.h>
 133#include <net/xfrm.h>
 134#include <linux/ipsec.h>
 135#include <net/cls_cgroup.h>
 136#include <net/netprio_cgroup.h>
 137#include <linux/sock_diag.h>
 138
 139#include <linux/filter.h>
 140#include <net/sock_reuseport.h>
 141#include <net/bpf_sk_storage.h>
 142
 143#include <trace/events/sock.h>
 144
 145#include <net/tcp.h>
 146#include <net/busy_poll.h>
 147#include <net/phonet/phonet.h>
 148
 149#include <linux/ethtool.h>
 150
 151#include "dev.h"
 152
 153static DEFINE_MUTEX(proto_list_mutex);
 154static LIST_HEAD(proto_list);
 155
 156static void sock_def_write_space_wfree(struct sock *sk);
 157static void sock_def_write_space(struct sock *sk);
 158
 159/**
 160 * sk_ns_capable - General socket capability test
 161 * @sk: Socket to use a capability on or through
 162 * @user_ns: The user namespace of the capability to use
 163 * @cap: The capability to use
 164 *
 165 * Test to see if the opener of the socket had when the socket was
 166 * created and the current process has the capability @cap in the user
 167 * namespace @user_ns.
 168 */
 169bool sk_ns_capable(const struct sock *sk,
 170		   struct user_namespace *user_ns, int cap)
 171{
 172	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
 173		ns_capable(user_ns, cap);
 174}
 175EXPORT_SYMBOL(sk_ns_capable);
 176
 177/**
 178 * sk_capable - Socket global capability test
 179 * @sk: Socket to use a capability on or through
 180 * @cap: The global capability to use
 181 *
 182 * Test to see if the opener of the socket had when the socket was
 183 * created and the current process has the capability @cap in all user
 184 * namespaces.
 185 */
 186bool sk_capable(const struct sock *sk, int cap)
 187{
 188	return sk_ns_capable(sk, &init_user_ns, cap);
 189}
 190EXPORT_SYMBOL(sk_capable);
 191
 192/**
 193 * sk_net_capable - Network namespace socket capability test
 194 * @sk: Socket to use a capability on or through
 195 * @cap: The capability to use
 196 *
 197 * Test to see if the opener of the socket had when the socket was created
 198 * and the current process has the capability @cap over the network namespace
 199 * the socket is a member of.
 200 */
 201bool sk_net_capable(const struct sock *sk, int cap)
 202{
 203	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
 204}
 205EXPORT_SYMBOL(sk_net_capable);
 206
 207/*
 208 * Each address family might have different locking rules, so we have
 209 * one slock key per address family and separate keys for internal and
 210 * userspace sockets.
 211 */
 212static struct lock_class_key af_family_keys[AF_MAX];
 213static struct lock_class_key af_family_kern_keys[AF_MAX];
 214static struct lock_class_key af_family_slock_keys[AF_MAX];
 215static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
 216
 217/*
 218 * Make lock validator output more readable. (we pre-construct these
 219 * strings build-time, so that runtime initialization of socket
 220 * locks is fast):
 221 */
 222
 223#define _sock_locks(x)						  \
 224  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
 225  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
 226  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
 227  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
 228  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
 229  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
 230  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
 231  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
 232  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
 233  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
 234  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
 235  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
 236  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
 237  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
 238  x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
 239  x "AF_MCTP"  , \
 240  x "AF_MAX"
 241
 242static const char *const af_family_key_strings[AF_MAX+1] = {
 243	_sock_locks("sk_lock-")
 244};
 245static const char *const af_family_slock_key_strings[AF_MAX+1] = {
 246	_sock_locks("slock-")
 247};
 248static const char *const af_family_clock_key_strings[AF_MAX+1] = {
 249	_sock_locks("clock-")
 250};
 251
 252static const char *const af_family_kern_key_strings[AF_MAX+1] = {
 253	_sock_locks("k-sk_lock-")
 254};
 255static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
 256	_sock_locks("k-slock-")
 257};
 258static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
 259	_sock_locks("k-clock-")
 260};
 261static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
 262	_sock_locks("rlock-")
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 263};
 264static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
 265	_sock_locks("wlock-")
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 266};
 267static const char *const af_family_elock_key_strings[AF_MAX+1] = {
 268	_sock_locks("elock-")
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 269};
 270
 271/*
 272 * sk_callback_lock and sk queues locking rules are per-address-family,
 273 * so split the lock classes by using a per-AF key:
 274 */
 275static struct lock_class_key af_callback_keys[AF_MAX];
 276static struct lock_class_key af_rlock_keys[AF_MAX];
 277static struct lock_class_key af_wlock_keys[AF_MAX];
 278static struct lock_class_key af_elock_keys[AF_MAX];
 279static struct lock_class_key af_kern_callback_keys[AF_MAX];
 280
 281/* Run time adjustable parameters. */
 282__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 283EXPORT_SYMBOL(sysctl_wmem_max);
 284__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 285EXPORT_SYMBOL(sysctl_rmem_max);
 286__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 287__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 288
 289DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
 290EXPORT_SYMBOL_GPL(memalloc_socks_key);
 
 
 
 
 
 
 291
 292/**
 293 * sk_set_memalloc - sets %SOCK_MEMALLOC
 294 * @sk: socket to set it on
 295 *
 296 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 297 * It's the responsibility of the admin to adjust min_free_kbytes
 298 * to meet the requirements
 299 */
 300void sk_set_memalloc(struct sock *sk)
 301{
 302	sock_set_flag(sk, SOCK_MEMALLOC);
 303	sk->sk_allocation |= __GFP_MEMALLOC;
 304	static_branch_inc(&memalloc_socks_key);
 305}
 306EXPORT_SYMBOL_GPL(sk_set_memalloc);
 307
 308void sk_clear_memalloc(struct sock *sk)
 309{
 310	sock_reset_flag(sk, SOCK_MEMALLOC);
 311	sk->sk_allocation &= ~__GFP_MEMALLOC;
 312	static_branch_dec(&memalloc_socks_key);
 313
 314	/*
 315	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 316	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 317	 * it has rmem allocations due to the last swapfile being deactivated
 318	 * but there is a risk that the socket is unusable due to exceeding
 319	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 320	 */
 321	sk_mem_reclaim(sk);
 322}
 323EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 324
 325int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 326{
 327	int ret;
 328	unsigned int noreclaim_flag;
 329
 330	/* these should have been dropped before queueing */
 331	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 332
 333	noreclaim_flag = memalloc_noreclaim_save();
 334	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
 335				 tcp_v6_do_rcv,
 336				 tcp_v4_do_rcv,
 337				 sk, skb);
 338	memalloc_noreclaim_restore(noreclaim_flag);
 339
 340	return ret;
 341}
 342EXPORT_SYMBOL(__sk_backlog_rcv);
 343
 344void sk_error_report(struct sock *sk)
 345{
 346	sk->sk_error_report(sk);
 347
 348	switch (sk->sk_family) {
 349	case AF_INET:
 350		fallthrough;
 351	case AF_INET6:
 352		trace_inet_sk_error_report(sk);
 353		break;
 354	default:
 355		break;
 356	}
 357}
 358EXPORT_SYMBOL(sk_error_report);
 359
 360int sock_get_timeout(long timeo, void *optval, bool old_timeval)
 361{
 362	struct __kernel_sock_timeval tv;
 363
 364	if (timeo == MAX_SCHEDULE_TIMEOUT) {
 365		tv.tv_sec = 0;
 366		tv.tv_usec = 0;
 367	} else {
 368		tv.tv_sec = timeo / HZ;
 369		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
 370	}
 371
 372	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 373		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
 374		*(struct old_timeval32 *)optval = tv32;
 375		return sizeof(tv32);
 376	}
 377
 378	if (old_timeval) {
 379		struct __kernel_old_timeval old_tv;
 380		old_tv.tv_sec = tv.tv_sec;
 381		old_tv.tv_usec = tv.tv_usec;
 382		*(struct __kernel_old_timeval *)optval = old_tv;
 383		return sizeof(old_tv);
 384	}
 385
 386	*(struct __kernel_sock_timeval *)optval = tv;
 387	return sizeof(tv);
 388}
 389EXPORT_SYMBOL(sock_get_timeout);
 390
 391int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
 392			   sockptr_t optval, int optlen, bool old_timeval)
 393{
 394	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 395		struct old_timeval32 tv32;
 396
 397		if (optlen < sizeof(tv32))
 398			return -EINVAL;
 399
 400		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
 401			return -EFAULT;
 402		tv->tv_sec = tv32.tv_sec;
 403		tv->tv_usec = tv32.tv_usec;
 404	} else if (old_timeval) {
 405		struct __kernel_old_timeval old_tv;
 406
 407		if (optlen < sizeof(old_tv))
 408			return -EINVAL;
 409		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
 410			return -EFAULT;
 411		tv->tv_sec = old_tv.tv_sec;
 412		tv->tv_usec = old_tv.tv_usec;
 413	} else {
 414		if (optlen < sizeof(*tv))
 415			return -EINVAL;
 416		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
 417			return -EFAULT;
 418	}
 419
 420	return 0;
 421}
 422EXPORT_SYMBOL(sock_copy_user_timeval);
 423
 424static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
 425			    bool old_timeval)
 426{
 427	struct __kernel_sock_timeval tv;
 428	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
 429	long val;
 430
 431	if (err)
 432		return err;
 433
 
 
 
 
 434	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 435		return -EDOM;
 436
 437	if (tv.tv_sec < 0) {
 438		static int warned __read_mostly;
 439
 440		WRITE_ONCE(*timeo_p, 0);
 441		if (warned < 10 && net_ratelimit()) {
 442			warned++;
 443			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 444				__func__, current->comm, task_pid_nr(current));
 445		}
 446		return 0;
 447	}
 448	val = MAX_SCHEDULE_TIMEOUT;
 449	if ((tv.tv_sec || tv.tv_usec) &&
 450	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
 451		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
 452						    USEC_PER_SEC / HZ);
 453	WRITE_ONCE(*timeo_p, val);
 454	return 0;
 455}
 456
 
 
 
 
 
 
 
 
 
 
 
 
 457static bool sock_needs_netstamp(const struct sock *sk)
 458{
 459	switch (sk->sk_family) {
 460	case AF_UNSPEC:
 461	case AF_UNIX:
 462		return false;
 463	default:
 464		return true;
 465	}
 466}
 467
 468static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 469{
 470	if (sk->sk_flags & flags) {
 471		sk->sk_flags &= ~flags;
 472		if (sock_needs_netstamp(sk) &&
 473		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 474			net_disable_timestamp();
 475	}
 476}
 477
 478
 479int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 480{
 481	unsigned long flags;
 482	struct sk_buff_head *list = &sk->sk_receive_queue;
 483
 484	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
 485		atomic_inc(&sk->sk_drops);
 486		trace_sock_rcvqueue_full(sk, skb);
 487		return -ENOMEM;
 488	}
 489
 490	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 491		atomic_inc(&sk->sk_drops);
 492		return -ENOBUFS;
 493	}
 494
 495	skb->dev = NULL;
 496	skb_set_owner_r(skb, sk);
 497
 498	/* we escape from rcu protected region, make sure we dont leak
 499	 * a norefcounted dst
 500	 */
 501	skb_dst_force(skb);
 502
 503	spin_lock_irqsave(&list->lock, flags);
 504	sock_skb_set_dropcount(sk, skb);
 505	__skb_queue_tail(list, skb);
 506	spin_unlock_irqrestore(&list->lock, flags);
 507
 508	if (!sock_flag(sk, SOCK_DEAD))
 509		sk->sk_data_ready(sk);
 510	return 0;
 511}
 512EXPORT_SYMBOL(__sock_queue_rcv_skb);
 513
 514int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
 515			      enum skb_drop_reason *reason)
 516{
 517	enum skb_drop_reason drop_reason;
 518	int err;
 519
 520	err = sk_filter(sk, skb);
 521	if (err) {
 522		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
 523		goto out;
 524	}
 525	err = __sock_queue_rcv_skb(sk, skb);
 526	switch (err) {
 527	case -ENOMEM:
 528		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
 529		break;
 530	case -ENOBUFS:
 531		drop_reason = SKB_DROP_REASON_PROTO_MEM;
 532		break;
 533	default:
 534		drop_reason = SKB_NOT_DROPPED_YET;
 535		break;
 536	}
 537out:
 538	if (reason)
 539		*reason = drop_reason;
 540	return err;
 541}
 542EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
 543
 544int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
 545		     const int nested, unsigned int trim_cap, bool refcounted)
 546{
 547	int rc = NET_RX_SUCCESS;
 548
 549	if (sk_filter_trim_cap(sk, skb, trim_cap))
 550		goto discard_and_relse;
 551
 552	skb->dev = NULL;
 553
 554	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
 555		atomic_inc(&sk->sk_drops);
 556		goto discard_and_relse;
 557	}
 558	if (nested)
 559		bh_lock_sock_nested(sk);
 560	else
 561		bh_lock_sock(sk);
 562	if (!sock_owned_by_user(sk)) {
 563		/*
 564		 * trylock + unlock semantics:
 565		 */
 566		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 567
 568		rc = sk_backlog_rcv(sk, skb);
 569
 570		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
 571	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
 572		bh_unlock_sock(sk);
 573		atomic_inc(&sk->sk_drops);
 574		goto discard_and_relse;
 575	}
 576
 577	bh_unlock_sock(sk);
 578out:
 579	if (refcounted)
 580		sock_put(sk);
 581	return rc;
 582discard_and_relse:
 583	kfree_skb(skb);
 584	goto out;
 585}
 586EXPORT_SYMBOL(__sk_receive_skb);
 587
 588INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
 589							  u32));
 590INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
 591							   u32));
 592struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 593{
 594	struct dst_entry *dst = __sk_dst_get(sk);
 595
 596	if (dst && dst->obsolete &&
 597	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 598			       dst, cookie) == NULL) {
 599		sk_tx_queue_clear(sk);
 600		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
 601		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 602		dst_release(dst);
 603		return NULL;
 604	}
 605
 606	return dst;
 607}
 608EXPORT_SYMBOL(__sk_dst_check);
 609
 610struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 611{
 612	struct dst_entry *dst = sk_dst_get(sk);
 613
 614	if (dst && dst->obsolete &&
 615	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
 616			       dst, cookie) == NULL) {
 617		sk_dst_reset(sk);
 618		dst_release(dst);
 619		return NULL;
 620	}
 621
 622	return dst;
 623}
 624EXPORT_SYMBOL(sk_dst_check);
 625
 626static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
 
 627{
 628	int ret = -ENOPROTOOPT;
 629#ifdef CONFIG_NETDEVICES
 630	struct net *net = sock_net(sk);
 
 
 631
 632	/* Sorry... */
 633	ret = -EPERM;
 634	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
 635		goto out;
 636
 637	ret = -EINVAL;
 638	if (ifindex < 0)
 639		goto out;
 640
 641	/* Paired with all READ_ONCE() done locklessly. */
 642	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
 643
 644	if (sk->sk_prot->rehash)
 645		sk->sk_prot->rehash(sk);
 646	sk_dst_reset(sk);
 647
 648	ret = 0;
 649
 650out:
 651#endif
 652
 653	return ret;
 654}
 655
 656int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
 657{
 658	int ret;
 659
 660	if (lock_sk)
 661		lock_sock(sk);
 662	ret = sock_bindtoindex_locked(sk, ifindex);
 663	if (lock_sk)
 664		release_sock(sk);
 665
 666	return ret;
 667}
 668EXPORT_SYMBOL(sock_bindtoindex);
 669
 670static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
 671{
 672	int ret = -ENOPROTOOPT;
 673#ifdef CONFIG_NETDEVICES
 674	struct net *net = sock_net(sk);
 675	char devname[IFNAMSIZ];
 676	int index;
 677
 678	ret = -EINVAL;
 679	if (optlen < 0)
 680		goto out;
 681
 682	/* Bind this socket to a particular device like "eth0",
 683	 * as specified in the passed interface name. If the
 684	 * name is "" or the option length is zero the socket
 685	 * is not bound.
 686	 */
 687	if (optlen > IFNAMSIZ - 1)
 688		optlen = IFNAMSIZ - 1;
 689	memset(devname, 0, sizeof(devname));
 690
 691	ret = -EFAULT;
 692	if (copy_from_sockptr(devname, optval, optlen))
 693		goto out;
 694
 695	index = 0;
 696	if (devname[0] != '\0') {
 697		struct net_device *dev;
 698
 699		rcu_read_lock();
 700		dev = dev_get_by_name_rcu(net, devname);
 701		if (dev)
 702			index = dev->ifindex;
 703		rcu_read_unlock();
 704		ret = -ENODEV;
 705		if (!dev)
 706			goto out;
 707	}
 708
 709	sockopt_lock_sock(sk);
 710	ret = sock_bindtoindex_locked(sk, index);
 711	sockopt_release_sock(sk);
 
 
 
 
 712out:
 713#endif
 714
 715	return ret;
 716}
 717
 718static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
 719				sockptr_t optlen, int len)
 720{
 721	int ret = -ENOPROTOOPT;
 722#ifdef CONFIG_NETDEVICES
 723	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 724	struct net *net = sock_net(sk);
 725	char devname[IFNAMSIZ];
 726
 727	if (bound_dev_if == 0) {
 728		len = 0;
 729		goto zero;
 730	}
 731
 732	ret = -EINVAL;
 733	if (len < IFNAMSIZ)
 734		goto out;
 735
 736	ret = netdev_get_name(net, devname, bound_dev_if);
 737	if (ret)
 738		goto out;
 739
 740	len = strlen(devname) + 1;
 741
 742	ret = -EFAULT;
 743	if (copy_to_sockptr(optval, devname, len))
 744		goto out;
 745
 746zero:
 747	ret = -EFAULT;
 748	if (copy_to_sockptr(optlen, &len, sizeof(int)))
 749		goto out;
 750
 751	ret = 0;
 752
 753out:
 754#endif
 755
 756	return ret;
 757}
 758
 759bool sk_mc_loop(const struct sock *sk)
 
 
 
 
 
 
 
 
 760{
 761	if (dev_recursion_level())
 762		return false;
 763	if (!sk)
 764		return true;
 765	/* IPV6_ADDRFORM can change sk->sk_family under us. */
 766	switch (READ_ONCE(sk->sk_family)) {
 767	case AF_INET:
 768		return inet_test_bit(MC_LOOP, sk);
 769#if IS_ENABLED(CONFIG_IPV6)
 770	case AF_INET6:
 771		return inet6_test_bit(MC6_LOOP, sk);
 772#endif
 773	}
 774	WARN_ON_ONCE(1);
 775	return true;
 776}
 777EXPORT_SYMBOL(sk_mc_loop);
 778
 779void sock_set_reuseaddr(struct sock *sk)
 780{
 781	lock_sock(sk);
 782	sk->sk_reuse = SK_CAN_REUSE;
 783	release_sock(sk);
 784}
 785EXPORT_SYMBOL(sock_set_reuseaddr);
 786
 787void sock_set_reuseport(struct sock *sk)
 788{
 789	lock_sock(sk);
 790	sk->sk_reuseport = true;
 791	release_sock(sk);
 792}
 793EXPORT_SYMBOL(sock_set_reuseport);
 794
 795void sock_no_linger(struct sock *sk)
 796{
 797	lock_sock(sk);
 798	WRITE_ONCE(sk->sk_lingertime, 0);
 799	sock_set_flag(sk, SOCK_LINGER);
 800	release_sock(sk);
 801}
 802EXPORT_SYMBOL(sock_no_linger);
 803
 804void sock_set_priority(struct sock *sk, u32 priority)
 805{
 806	WRITE_ONCE(sk->sk_priority, priority);
 807}
 808EXPORT_SYMBOL(sock_set_priority);
 809
 810void sock_set_sndtimeo(struct sock *sk, s64 secs)
 811{
 812	lock_sock(sk);
 813	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
 814		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
 815	else
 816		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
 817	release_sock(sk);
 818}
 819EXPORT_SYMBOL(sock_set_sndtimeo);
 820
 821static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
 822{
 823	sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
 824	sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
 825	if (val)  {
 826		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
 827		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 828	}
 829}
 830
 831void sock_enable_timestamps(struct sock *sk)
 832{
 833	lock_sock(sk);
 834	__sock_set_timestamps(sk, true, false, true);
 835	release_sock(sk);
 836}
 837EXPORT_SYMBOL(sock_enable_timestamps);
 838
 839void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
 840{
 841	switch (optname) {
 842	case SO_TIMESTAMP_OLD:
 843		__sock_set_timestamps(sk, valbool, false, false);
 844		break;
 845	case SO_TIMESTAMP_NEW:
 846		__sock_set_timestamps(sk, valbool, true, false);
 847		break;
 848	case SO_TIMESTAMPNS_OLD:
 849		__sock_set_timestamps(sk, valbool, false, true);
 850		break;
 851	case SO_TIMESTAMPNS_NEW:
 852		__sock_set_timestamps(sk, valbool, true, true);
 853		break;
 854	}
 855}
 856
 857static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
 858{
 859	struct net *net = sock_net(sk);
 860	struct net_device *dev = NULL;
 861	bool match = false;
 862	int *vclock_index;
 863	int i, num;
 864
 865	if (sk->sk_bound_dev_if)
 866		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
 867
 868	if (!dev) {
 869		pr_err("%s: sock not bind to device\n", __func__);
 870		return -EOPNOTSUPP;
 871	}
 872
 873	num = ethtool_get_phc_vclocks(dev, &vclock_index);
 874	dev_put(dev);
 875
 876	for (i = 0; i < num; i++) {
 877		if (*(vclock_index + i) == phc_index) {
 878			match = true;
 879			break;
 880		}
 881	}
 882
 883	if (num > 0)
 884		kfree(vclock_index);
 885
 886	if (!match)
 887		return -EINVAL;
 888
 889	WRITE_ONCE(sk->sk_bind_phc, phc_index);
 890
 891	return 0;
 892}
 893
 894int sock_set_timestamping(struct sock *sk, int optname,
 895			  struct so_timestamping timestamping)
 896{
 897	int val = timestamping.flags;
 898	int ret;
 899
 900	if (val & ~SOF_TIMESTAMPING_MASK)
 901		return -EINVAL;
 902
 903	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
 904	    !(val & SOF_TIMESTAMPING_OPT_ID))
 905		return -EINVAL;
 906
 907	if (val & SOF_TIMESTAMPING_OPT_ID &&
 908	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
 909		if (sk_is_tcp(sk)) {
 910			if ((1 << sk->sk_state) &
 911			    (TCPF_CLOSE | TCPF_LISTEN))
 912				return -EINVAL;
 913			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
 914				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
 915			else
 916				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
 917		} else {
 918			atomic_set(&sk->sk_tskey, 0);
 919		}
 920	}
 921
 922	if (val & SOF_TIMESTAMPING_OPT_STATS &&
 923	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
 924		return -EINVAL;
 925
 926	if (val & SOF_TIMESTAMPING_BIND_PHC) {
 927		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
 928		if (ret)
 929			return ret;
 930	}
 931
 932	WRITE_ONCE(sk->sk_tsflags, val);
 933	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
 934
 935	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
 936		sock_enable_timestamp(sk,
 937				      SOCK_TIMESTAMPING_RX_SOFTWARE);
 938	else
 939		sock_disable_timestamp(sk,
 940				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
 941	return 0;
 942}
 943
 944void sock_set_keepalive(struct sock *sk)
 945{
 946	lock_sock(sk);
 947	if (sk->sk_prot->keepalive)
 948		sk->sk_prot->keepalive(sk, true);
 949	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
 950	release_sock(sk);
 951}
 952EXPORT_SYMBOL(sock_set_keepalive);
 953
 954static void __sock_set_rcvbuf(struct sock *sk, int val)
 955{
 956	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
 957	 * as a negative value.
 958	 */
 959	val = min_t(int, val, INT_MAX / 2);
 960	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 961
 962	/* We double it on the way in to account for "struct sk_buff" etc.
 963	 * overhead.   Applications assume that the SO_RCVBUF setting they make
 964	 * will allow that much actual data to be received on that socket.
 965	 *
 966	 * Applications are unaware that "struct sk_buff" and other overheads
 967	 * allocate from the receive buffer during socket buffer allocation.
 968	 *
 969	 * And after considering the possible alternatives, returning the value
 970	 * we actually used in getsockopt is the most desirable behavior.
 971	 */
 972	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
 973}
 974
 975void sock_set_rcvbuf(struct sock *sk, int val)
 976{
 977	lock_sock(sk);
 978	__sock_set_rcvbuf(sk, val);
 979	release_sock(sk);
 980}
 981EXPORT_SYMBOL(sock_set_rcvbuf);
 982
 983static void __sock_set_mark(struct sock *sk, u32 val)
 984{
 985	if (val != sk->sk_mark) {
 986		WRITE_ONCE(sk->sk_mark, val);
 987		sk_dst_reset(sk);
 988	}
 989}
 990
 991void sock_set_mark(struct sock *sk, u32 val)
 992{
 993	lock_sock(sk);
 994	__sock_set_mark(sk, val);
 995	release_sock(sk);
 996}
 997EXPORT_SYMBOL(sock_set_mark);
 998
 999static void sock_release_reserved_memory(struct sock *sk, int bytes)
1000{
1001	/* Round down bytes to multiple of pages */
1002	bytes = round_down(bytes, PAGE_SIZE);
1003
1004	WARN_ON(bytes > sk->sk_reserved_mem);
1005	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1006	sk_mem_reclaim(sk);
1007}
1008
1009static int sock_reserve_memory(struct sock *sk, int bytes)
1010{
1011	long allocated;
1012	bool charged;
1013	int pages;
1014
1015	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1016		return -EOPNOTSUPP;
1017
1018	if (!bytes)
1019		return 0;
1020
1021	pages = sk_mem_pages(bytes);
1022
1023	/* pre-charge to memcg */
1024	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1025					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1026	if (!charged)
1027		return -ENOMEM;
1028
1029	/* pre-charge to forward_alloc */
1030	sk_memory_allocated_add(sk, pages);
1031	allocated = sk_memory_allocated(sk);
1032	/* If the system goes into memory pressure with this
1033	 * precharge, give up and return error.
1034	 */
1035	if (allocated > sk_prot_mem_limits(sk, 1)) {
1036		sk_memory_allocated_sub(sk, pages);
1037		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1038		return -ENOMEM;
1039	}
1040	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1041
1042	WRITE_ONCE(sk->sk_reserved_mem,
1043		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1044
1045	return 0;
1046}
1047
1048#ifdef CONFIG_PAGE_POOL
1049
1050/* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1051 * in 1 syscall. The limit exists to limit the amount of memory the kernel
1052 * allocates to copy these tokens, and to prevent looping over the frags for
1053 * too long.
1054 */
1055#define MAX_DONTNEED_TOKENS 128
1056#define MAX_DONTNEED_FRAGS 1024
1057
1058static noinline_for_stack int
1059sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1060{
1061	unsigned int num_tokens, i, j, k, netmem_num = 0;
1062	struct dmabuf_token *tokens;
1063	int ret = 0, num_frags = 0;
1064	netmem_ref netmems[16];
1065
1066	if (!sk_is_tcp(sk))
1067		return -EBADF;
1068
1069	if (optlen % sizeof(*tokens) ||
1070	    optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1071		return -EINVAL;
1072
1073	num_tokens = optlen / sizeof(*tokens);
1074	tokens = kvmalloc_array(num_tokens, sizeof(*tokens), GFP_KERNEL);
1075	if (!tokens)
1076		return -ENOMEM;
1077
1078	if (copy_from_sockptr(tokens, optval, optlen)) {
1079		kvfree(tokens);
1080		return -EFAULT;
1081	}
1082
1083	xa_lock_bh(&sk->sk_user_frags);
1084	for (i = 0; i < num_tokens; i++) {
1085		for (j = 0; j < tokens[i].token_count; j++) {
1086			if (++num_frags > MAX_DONTNEED_FRAGS)
1087				goto frag_limit_reached;
1088
1089			netmem_ref netmem = (__force netmem_ref)__xa_erase(
1090				&sk->sk_user_frags, tokens[i].token_start + j);
1091
1092			if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1093				continue;
1094
1095			netmems[netmem_num++] = netmem;
1096			if (netmem_num == ARRAY_SIZE(netmems)) {
1097				xa_unlock_bh(&sk->sk_user_frags);
1098				for (k = 0; k < netmem_num; k++)
1099					WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1100				netmem_num = 0;
1101				xa_lock_bh(&sk->sk_user_frags);
1102			}
1103			ret++;
1104		}
1105	}
1106
1107frag_limit_reached:
1108	xa_unlock_bh(&sk->sk_user_frags);
1109	for (k = 0; k < netmem_num; k++)
1110		WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1111
1112	kvfree(tokens);
1113	return ret;
1114}
1115#endif
1116
1117void sockopt_lock_sock(struct sock *sk)
1118{
1119	/* When current->bpf_ctx is set, the setsockopt is called from
1120	 * a bpf prog.  bpf has ensured the sk lock has been
1121	 * acquired before calling setsockopt().
1122	 */
1123	if (has_current_bpf_ctx())
1124		return;
1125
1126	lock_sock(sk);
1127}
1128EXPORT_SYMBOL(sockopt_lock_sock);
1129
1130void sockopt_release_sock(struct sock *sk)
1131{
1132	if (has_current_bpf_ctx())
1133		return;
1134
1135	release_sock(sk);
1136}
1137EXPORT_SYMBOL(sockopt_release_sock);
1138
1139bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1140{
1141	return has_current_bpf_ctx() || ns_capable(ns, cap);
1142}
1143EXPORT_SYMBOL(sockopt_ns_capable);
1144
1145bool sockopt_capable(int cap)
1146{
1147	return has_current_bpf_ctx() || capable(cap);
1148}
1149EXPORT_SYMBOL(sockopt_capable);
1150
1151static int sockopt_validate_clockid(__kernel_clockid_t value)
1152{
1153	switch (value) {
1154	case CLOCK_REALTIME:
1155	case CLOCK_MONOTONIC:
1156	case CLOCK_TAI:
1157		return 0;
1158	}
1159	return -EINVAL;
1160}
1161
1162/*
1163 *	This is meant for all protocols to use and covers goings on
1164 *	at the socket level. Everything here is generic.
1165 */
1166
1167int sk_setsockopt(struct sock *sk, int level, int optname,
1168		  sockptr_t optval, unsigned int optlen)
1169{
1170	struct so_timestamping timestamping;
1171	struct socket *sock = sk->sk_socket;
1172	struct sock_txtime sk_txtime;
1173	int val;
1174	int valbool;
1175	struct linger ling;
1176	int ret = 0;
1177
1178	/*
1179	 *	Options without arguments
1180	 */
1181
1182	if (optname == SO_BINDTODEVICE)
1183		return sock_setbindtodevice(sk, optval, optlen);
1184
1185	if (optlen < sizeof(int))
1186		return -EINVAL;
1187
1188	if (copy_from_sockptr(&val, optval, sizeof(val)))
1189		return -EFAULT;
1190
1191	valbool = val ? 1 : 0;
1192
1193	/* handle options which do not require locking the socket. */
1194	switch (optname) {
1195	case SO_PRIORITY:
1196		if ((val >= 0 && val <= 6) ||
1197		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1198		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1199			sock_set_priority(sk, val);
1200			return 0;
1201		}
1202		return -EPERM;
1203	case SO_PASSSEC:
1204		assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1205		return 0;
1206	case SO_PASSCRED:
1207		assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1208		return 0;
1209	case SO_PASSPIDFD:
1210		assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1211		return 0;
1212	case SO_TYPE:
1213	case SO_PROTOCOL:
1214	case SO_DOMAIN:
1215	case SO_ERROR:
1216		return -ENOPROTOOPT;
1217#ifdef CONFIG_NET_RX_BUSY_POLL
1218	case SO_BUSY_POLL:
1219		if (val < 0)
1220			return -EINVAL;
1221		WRITE_ONCE(sk->sk_ll_usec, val);
1222		return 0;
1223	case SO_PREFER_BUSY_POLL:
1224		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1225			return -EPERM;
1226		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1227		return 0;
1228	case SO_BUSY_POLL_BUDGET:
1229		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1230		    !sockopt_capable(CAP_NET_ADMIN))
1231			return -EPERM;
1232		if (val < 0 || val > U16_MAX)
1233			return -EINVAL;
1234		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1235		return 0;
1236#endif
1237	case SO_MAX_PACING_RATE:
1238		{
1239		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1240		unsigned long pacing_rate;
1241
1242		if (sizeof(ulval) != sizeof(val) &&
1243		    optlen >= sizeof(ulval) &&
1244		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1245			return -EFAULT;
1246		}
1247		if (ulval != ~0UL)
1248			cmpxchg(&sk->sk_pacing_status,
1249				SK_PACING_NONE,
1250				SK_PACING_NEEDED);
1251		/* Pairs with READ_ONCE() from sk_getsockopt() */
1252		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1253		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1254		if (ulval < pacing_rate)
1255			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1256		return 0;
1257		}
1258	case SO_TXREHASH:
1259		if (val < -1 || val > 1)
1260			return -EINVAL;
1261		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1262			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1263		/* Paired with READ_ONCE() in tcp_rtx_synack()
1264		 * and sk_getsockopt().
1265		 */
1266		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1267		return 0;
1268	case SO_PEEK_OFF:
1269		{
1270		int (*set_peek_off)(struct sock *sk, int val);
1271
1272		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1273		if (set_peek_off)
1274			ret = set_peek_off(sk, val);
1275		else
1276			ret = -EOPNOTSUPP;
1277		return ret;
1278		}
1279#ifdef CONFIG_PAGE_POOL
1280	case SO_DEVMEM_DONTNEED:
1281		return sock_devmem_dontneed(sk, optval, optlen);
1282#endif
1283	}
1284
1285	sockopt_lock_sock(sk);
1286
1287	switch (optname) {
1288	case SO_DEBUG:
1289		if (val && !sockopt_capable(CAP_NET_ADMIN))
1290			ret = -EACCES;
1291		else
1292			sock_valbool_flag(sk, SOCK_DBG, valbool);
1293		break;
1294	case SO_REUSEADDR:
1295		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1296		break;
1297	case SO_REUSEPORT:
1298		if (valbool && !sk_is_inet(sk))
1299			ret = -EOPNOTSUPP;
1300		else
1301			sk->sk_reuseport = valbool;
 
 
 
1302		break;
1303	case SO_DONTROUTE:
1304		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1305		sk_dst_reset(sk);
1306		break;
1307	case SO_BROADCAST:
1308		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1309		break;
1310	case SO_SNDBUF:
1311		/* Don't error on this BSD doesn't and if you think
1312		 * about it this is right. Otherwise apps have to
1313		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1314		 * are treated in BSD as hints
1315		 */
1316		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1317set_sndbuf:
1318		/* Ensure val * 2 fits into an int, to prevent max_t()
1319		 * from treating it as a negative value.
1320		 */
1321		val = min_t(int, val, INT_MAX / 2);
1322		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1323		WRITE_ONCE(sk->sk_sndbuf,
1324			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1325		/* Wake up sending tasks if we upped the value. */
1326		sk->sk_write_space(sk);
1327		break;
1328
1329	case SO_SNDBUFFORCE:
1330		if (!sockopt_capable(CAP_NET_ADMIN)) {
1331			ret = -EPERM;
1332			break;
1333		}
1334
1335		/* No negative values (to prevent underflow, as val will be
1336		 * multiplied by 2).
1337		 */
1338		if (val < 0)
1339			val = 0;
1340		goto set_sndbuf;
1341
1342	case SO_RCVBUF:
1343		/* Don't error on this BSD doesn't and if you think
1344		 * about it this is right. Otherwise apps have to
1345		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1346		 * are treated in BSD as hints
1347		 */
1348		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1349		break;
1350
1351	case SO_RCVBUFFORCE:
1352		if (!sockopt_capable(CAP_NET_ADMIN)) {
1353			ret = -EPERM;
1354			break;
1355		}
1356
1357		/* No negative values (to prevent underflow, as val will be
1358		 * multiplied by 2).
1359		 */
1360		__sock_set_rcvbuf(sk, max(val, 0));
1361		break;
1362
1363	case SO_KEEPALIVE:
1364		if (sk->sk_prot->keepalive)
1365			sk->sk_prot->keepalive(sk, valbool);
1366		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1367		break;
1368
1369	case SO_OOBINLINE:
1370		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1371		break;
1372
1373	case SO_NO_CHECK:
1374		sk->sk_no_check_tx = valbool;
1375		break;
1376
 
 
 
 
 
 
 
 
1377	case SO_LINGER:
1378		if (optlen < sizeof(ling)) {
1379			ret = -EINVAL;	/* 1003.1g */
1380			break;
1381		}
1382		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1383			ret = -EFAULT;
1384			break;
1385		}
1386		if (!ling.l_onoff) {
1387			sock_reset_flag(sk, SOCK_LINGER);
1388		} else {
1389			unsigned long t_sec = ling.l_linger;
1390
1391			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1392				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1393			else
1394				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
 
1395			sock_set_flag(sk, SOCK_LINGER);
1396		}
1397		break;
1398
1399	case SO_BSDCOMPAT:
 
1400		break;
1401
1402	case SO_TIMESTAMP_OLD:
1403	case SO_TIMESTAMP_NEW:
1404	case SO_TIMESTAMPNS_OLD:
1405	case SO_TIMESTAMPNS_NEW:
1406		sock_set_timestamp(sk, optname, valbool);
1407		break;
1408
1409	case SO_TIMESTAMPING_NEW:
1410	case SO_TIMESTAMPING_OLD:
1411		if (optlen == sizeof(timestamping)) {
1412			if (copy_from_sockptr(&timestamping, optval,
1413					      sizeof(timestamping))) {
1414				ret = -EFAULT;
1415				break;
1416			}
 
1417		} else {
1418			memset(&timestamping, 0, sizeof(timestamping));
1419			timestamping.flags = val;
1420		}
1421		ret = sock_set_timestamping(sk, optname, timestamping);
1422		break;
1423
1424	case SO_RCVLOWAT:
1425		{
1426		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
 
 
1427
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1428		if (val < 0)
1429			val = INT_MAX;
1430		if (sock)
1431			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1432		if (set_rcvlowat)
1433			ret = set_rcvlowat(sk, val);
1434		else
1435			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1436		break;
1437		}
1438	case SO_RCVTIMEO_OLD:
1439	case SO_RCVTIMEO_NEW:
1440		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1441				       optlen, optname == SO_RCVTIMEO_OLD);
1442		break;
1443
1444	case SO_SNDTIMEO_OLD:
1445	case SO_SNDTIMEO_NEW:
1446		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1447				       optlen, optname == SO_SNDTIMEO_OLD);
1448		break;
1449
1450	case SO_ATTACH_FILTER: {
1451		struct sock_fprog fprog;
 
 
 
 
 
 
1452
1453		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1454		if (!ret)
1455			ret = sk_attach_filter(&fprog, sk);
 
1456		break;
1457	}
1458	case SO_ATTACH_BPF:
1459		ret = -EINVAL;
1460		if (optlen == sizeof(u32)) {
1461			u32 ufd;
1462
1463			ret = -EFAULT;
1464			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1465				break;
1466
1467			ret = sk_attach_bpf(ufd, sk);
1468		}
1469		break;
1470
1471	case SO_ATTACH_REUSEPORT_CBPF: {
1472		struct sock_fprog fprog;
 
 
 
 
 
 
1473
1474		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1475		if (!ret)
1476			ret = sk_reuseport_attach_filter(&fprog, sk);
 
1477		break;
1478	}
1479	case SO_ATTACH_REUSEPORT_EBPF:
1480		ret = -EINVAL;
1481		if (optlen == sizeof(u32)) {
1482			u32 ufd;
1483
1484			ret = -EFAULT;
1485			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1486				break;
1487
1488			ret = sk_reuseport_attach_bpf(ufd, sk);
1489		}
1490		break;
1491
1492	case SO_DETACH_REUSEPORT_BPF:
1493		ret = reuseport_detach_prog(sk);
1494		break;
1495
1496	case SO_DETACH_FILTER:
1497		ret = sk_detach_filter(sk);
1498		break;
1499
1500	case SO_LOCK_FILTER:
1501		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1502			ret = -EPERM;
1503		else
1504			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1505		break;
1506
 
 
 
 
 
 
1507	case SO_MARK:
1508		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1509		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1510			ret = -EPERM;
1511			break;
1512		}
1513
1514		__sock_set_mark(sk, val);
1515		break;
1516	case SO_RCVMARK:
1517		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1518		break;
1519
1520	case SO_RXQ_OVFL:
1521		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1522		break;
1523
1524	case SO_WIFI_STATUS:
1525		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1526		break;
1527
 
 
 
 
 
 
 
1528	case SO_NOFCS:
1529		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1530		break;
1531
1532	case SO_SELECT_ERR_QUEUE:
1533		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1534		break;
1535
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1536
1537	case SO_INCOMING_CPU:
1538		reuseport_update_incoming_cpu(sk, val);
1539		break;
1540
1541	case SO_CNX_ADVICE:
1542		if (val == 1)
1543			dst_negative_advice(sk);
1544		break;
1545
1546	case SO_ZEROCOPY:
1547		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1548			if (!(sk_is_tcp(sk) ||
1549			      (sk->sk_type == SOCK_DGRAM &&
1550			       sk->sk_protocol == IPPROTO_UDP)))
1551				ret = -EOPNOTSUPP;
1552		} else if (sk->sk_family != PF_RDS) {
1553			ret = -EOPNOTSUPP;
1554		}
1555		if (!ret) {
1556			if (val < 0 || val > 1)
1557				ret = -EINVAL;
1558			else
1559				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1560		}
1561		break;
1562
1563	case SO_TXTIME:
1564		if (optlen != sizeof(struct sock_txtime)) {
1565			ret = -EINVAL;
1566			break;
1567		} else if (copy_from_sockptr(&sk_txtime, optval,
1568			   sizeof(struct sock_txtime))) {
1569			ret = -EFAULT;
1570			break;
1571		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1572			ret = -EINVAL;
1573			break;
1574		}
1575		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1576		 * scheduler has enough safe guards.
1577		 */
1578		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1579		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1580			ret = -EPERM;
1581			break;
1582		}
1583
1584		ret = sockopt_validate_clockid(sk_txtime.clockid);
1585		if (ret)
1586			break;
1587
1588		sock_valbool_flag(sk, SOCK_TXTIME, true);
1589		sk->sk_clockid = sk_txtime.clockid;
1590		sk->sk_txtime_deadline_mode =
1591			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1592		sk->sk_txtime_report_errors =
1593			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1594		break;
1595
1596	case SO_BINDTOIFINDEX:
1597		ret = sock_bindtoindex_locked(sk, val);
1598		break;
1599
1600	case SO_BUF_LOCK:
1601		if (val & ~SOCK_BUF_LOCK_MASK) {
1602			ret = -EINVAL;
1603			break;
1604		}
1605		sk->sk_userlocks = val | (sk->sk_userlocks &
1606					  ~SOCK_BUF_LOCK_MASK);
1607		break;
1608
1609	case SO_RESERVE_MEM:
1610	{
1611		int delta;
1612
1613		if (val < 0) {
1614			ret = -EINVAL;
1615			break;
1616		}
1617
1618		delta = val - sk->sk_reserved_mem;
1619		if (delta < 0)
1620			sock_release_reserved_memory(sk, -delta);
1621		else
1622			ret = sock_reserve_memory(sk, delta);
1623		break;
1624	}
1625
1626	default:
1627		ret = -ENOPROTOOPT;
1628		break;
1629	}
1630	sockopt_release_sock(sk);
1631	return ret;
1632}
1633
1634int sock_setsockopt(struct socket *sock, int level, int optname,
1635		    sockptr_t optval, unsigned int optlen)
1636{
1637	return sk_setsockopt(sock->sk, level, optname,
1638			     optval, optlen);
1639}
1640EXPORT_SYMBOL(sock_setsockopt);
1641
1642static const struct cred *sk_get_peer_cred(struct sock *sk)
1643{
1644	const struct cred *cred;
1645
1646	spin_lock(&sk->sk_peer_lock);
1647	cred = get_cred(sk->sk_peer_cred);
1648	spin_unlock(&sk->sk_peer_lock);
1649
1650	return cred;
1651}
1652
1653static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1654			  struct ucred *ucred)
1655{
1656	ucred->pid = pid_vnr(pid);
1657	ucred->uid = ucred->gid = -1;
1658	if (cred) {
1659		struct user_namespace *current_ns = current_user_ns();
1660
1661		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1662		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1663	}
1664}
1665
1666static int groups_to_user(sockptr_t dst, const struct group_info *src)
1667{
1668	struct user_namespace *user_ns = current_user_ns();
1669	int i;
1670
1671	for (i = 0; i < src->ngroups; i++) {
1672		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1673
1674		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1675			return -EFAULT;
1676	}
1677
1678	return 0;
1679}
1680
1681int sk_getsockopt(struct sock *sk, int level, int optname,
1682		  sockptr_t optval, sockptr_t optlen)
1683{
1684	struct socket *sock = sk->sk_socket;
1685
1686	union {
1687		int val;
1688		u64 val64;
1689		unsigned long ulval;
1690		struct linger ling;
1691		struct old_timeval32 tm32;
1692		struct __kernel_old_timeval tm;
1693		struct  __kernel_sock_timeval stm;
1694		struct sock_txtime txtime;
1695		struct so_timestamping timestamping;
1696	} v;
1697
1698	int lv = sizeof(int);
1699	int len;
1700
1701	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1702		return -EFAULT;
1703	if (len < 0)
1704		return -EINVAL;
1705
1706	memset(&v, 0, sizeof(v));
1707
1708	switch (optname) {
1709	case SO_DEBUG:
1710		v.val = sock_flag(sk, SOCK_DBG);
1711		break;
1712
1713	case SO_DONTROUTE:
1714		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1715		break;
1716
1717	case SO_BROADCAST:
1718		v.val = sock_flag(sk, SOCK_BROADCAST);
1719		break;
1720
1721	case SO_SNDBUF:
1722		v.val = READ_ONCE(sk->sk_sndbuf);
1723		break;
1724
1725	case SO_RCVBUF:
1726		v.val = READ_ONCE(sk->sk_rcvbuf);
1727		break;
1728
1729	case SO_REUSEADDR:
1730		v.val = sk->sk_reuse;
1731		break;
1732
1733	case SO_REUSEPORT:
1734		v.val = sk->sk_reuseport;
1735		break;
1736
1737	case SO_KEEPALIVE:
1738		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1739		break;
1740
1741	case SO_TYPE:
1742		v.val = sk->sk_type;
1743		break;
1744
1745	case SO_PROTOCOL:
1746		v.val = sk->sk_protocol;
1747		break;
1748
1749	case SO_DOMAIN:
1750		v.val = sk->sk_family;
1751		break;
1752
1753	case SO_ERROR:
1754		v.val = -sock_error(sk);
1755		if (v.val == 0)
1756			v.val = xchg(&sk->sk_err_soft, 0);
1757		break;
1758
1759	case SO_OOBINLINE:
1760		v.val = sock_flag(sk, SOCK_URGINLINE);
1761		break;
1762
1763	case SO_NO_CHECK:
1764		v.val = sk->sk_no_check_tx;
1765		break;
1766
1767	case SO_PRIORITY:
1768		v.val = READ_ONCE(sk->sk_priority);
1769		break;
1770
1771	case SO_LINGER:
1772		lv		= sizeof(v.ling);
1773		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1774		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1775		break;
1776
1777	case SO_BSDCOMPAT:
 
1778		break;
1779
1780	case SO_TIMESTAMP_OLD:
1781		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1782				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1783				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1784		break;
1785
1786	case SO_TIMESTAMPNS_OLD:
1787		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1788		break;
1789
1790	case SO_TIMESTAMP_NEW:
1791		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1792		break;
1793
1794	case SO_TIMESTAMPNS_NEW:
1795		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1796		break;
1797
1798	case SO_TIMESTAMPING_OLD:
1799	case SO_TIMESTAMPING_NEW:
1800		lv = sizeof(v.timestamping);
1801		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1802		 * returning the flags when they were set through the same option.
1803		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1804		 */
1805		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1806			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1807			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1808		}
1809		break;
1810
1811	case SO_RCVTIMEO_OLD:
1812	case SO_RCVTIMEO_NEW:
1813		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1814				      SO_RCVTIMEO_OLD == optname);
1815		break;
1816
1817	case SO_SNDTIMEO_OLD:
1818	case SO_SNDTIMEO_NEW:
1819		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1820				      SO_SNDTIMEO_OLD == optname);
1821		break;
1822
1823	case SO_RCVLOWAT:
1824		v.val = READ_ONCE(sk->sk_rcvlowat);
1825		break;
1826
1827	case SO_SNDLOWAT:
1828		v.val = 1;
1829		break;
1830
1831	case SO_PASSCRED:
1832		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1833		break;
1834
1835	case SO_PASSPIDFD:
1836		v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1837		break;
1838
1839	case SO_PEERCRED:
1840	{
1841		struct ucred peercred;
1842		if (len > sizeof(peercred))
1843			len = sizeof(peercred);
1844
1845		spin_lock(&sk->sk_peer_lock);
1846		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1847		spin_unlock(&sk->sk_peer_lock);
1848
1849		if (copy_to_sockptr(optval, &peercred, len))
1850			return -EFAULT;
1851		goto lenout;
1852	}
1853
1854	case SO_PEERPIDFD:
1855	{
1856		struct pid *peer_pid;
1857		struct file *pidfd_file = NULL;
1858		int pidfd;
1859
1860		if (len > sizeof(pidfd))
1861			len = sizeof(pidfd);
1862
1863		spin_lock(&sk->sk_peer_lock);
1864		peer_pid = get_pid(sk->sk_peer_pid);
1865		spin_unlock(&sk->sk_peer_lock);
1866
1867		if (!peer_pid)
1868			return -ENODATA;
1869
1870		pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file);
1871		put_pid(peer_pid);
1872		if (pidfd < 0)
1873			return pidfd;
1874
1875		if (copy_to_sockptr(optval, &pidfd, len) ||
1876		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1877			put_unused_fd(pidfd);
1878			fput(pidfd_file);
1879
1880			return -EFAULT;
1881		}
1882
1883		fd_install(pidfd, pidfd_file);
1884		return 0;
1885	}
1886
1887	case SO_PEERGROUPS:
1888	{
1889		const struct cred *cred;
1890		int ret, n;
1891
1892		cred = sk_get_peer_cred(sk);
1893		if (!cred)
1894			return -ENODATA;
1895
1896		n = cred->group_info->ngroups;
1897		if (len < n * sizeof(gid_t)) {
1898			len = n * sizeof(gid_t);
1899			put_cred(cred);
1900			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1901		}
1902		len = n * sizeof(gid_t);
1903
1904		ret = groups_to_user(optval, cred->group_info);
1905		put_cred(cred);
1906		if (ret)
1907			return ret;
1908		goto lenout;
1909	}
1910
1911	case SO_PEERNAME:
1912	{
1913		struct sockaddr_storage address;
1914
1915		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1916		if (lv < 0)
1917			return -ENOTCONN;
1918		if (lv < len)
1919			return -EINVAL;
1920		if (copy_to_sockptr(optval, &address, len))
1921			return -EFAULT;
1922		goto lenout;
1923	}
1924
1925	/* Dubious BSD thing... Probably nobody even uses it, but
1926	 * the UNIX standard wants it for whatever reason... -DaveM
1927	 */
1928	case SO_ACCEPTCONN:
1929		v.val = sk->sk_state == TCP_LISTEN;
1930		break;
1931
1932	case SO_PASSSEC:
1933		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1934		break;
1935
1936	case SO_PEERSEC:
1937		return security_socket_getpeersec_stream(sock,
1938							 optval, optlen, len);
1939
1940	case SO_MARK:
1941		v.val = READ_ONCE(sk->sk_mark);
1942		break;
1943
1944	case SO_RCVMARK:
1945		v.val = sock_flag(sk, SOCK_RCVMARK);
1946		break;
1947
1948	case SO_RXQ_OVFL:
1949		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1950		break;
1951
1952	case SO_WIFI_STATUS:
1953		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1954		break;
1955
1956	case SO_PEEK_OFF:
1957		if (!READ_ONCE(sock->ops)->set_peek_off)
1958			return -EOPNOTSUPP;
1959
1960		v.val = READ_ONCE(sk->sk_peek_off);
1961		break;
1962	case SO_NOFCS:
1963		v.val = sock_flag(sk, SOCK_NOFCS);
1964		break;
1965
1966	case SO_BINDTODEVICE:
1967		return sock_getbindtodevice(sk, optval, optlen, len);
1968
1969	case SO_GET_FILTER:
1970		len = sk_get_filter(sk, optval, len);
1971		if (len < 0)
1972			return len;
1973
1974		goto lenout;
1975
1976	case SO_LOCK_FILTER:
1977		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1978		break;
1979
1980	case SO_BPF_EXTENSIONS:
1981		v.val = bpf_tell_extensions();
1982		break;
1983
1984	case SO_SELECT_ERR_QUEUE:
1985		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1986		break;
1987
1988#ifdef CONFIG_NET_RX_BUSY_POLL
1989	case SO_BUSY_POLL:
1990		v.val = READ_ONCE(sk->sk_ll_usec);
1991		break;
1992	case SO_PREFER_BUSY_POLL:
1993		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1994		break;
1995#endif
1996
1997	case SO_MAX_PACING_RATE:
1998		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
1999		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2000			lv = sizeof(v.ulval);
2001			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2002		} else {
2003			/* 32bit version */
2004			v.val = min_t(unsigned long, ~0U,
2005				      READ_ONCE(sk->sk_max_pacing_rate));
2006		}
2007		break;
2008
2009	case SO_INCOMING_CPU:
2010		v.val = READ_ONCE(sk->sk_incoming_cpu);
2011		break;
2012
2013	case SO_MEMINFO:
2014	{
2015		u32 meminfo[SK_MEMINFO_VARS];
2016
 
 
 
2017		sk_get_meminfo(sk, meminfo);
2018
2019		len = min_t(unsigned int, len, sizeof(meminfo));
2020		if (copy_to_sockptr(optval, &meminfo, len))
2021			return -EFAULT;
2022
2023		goto lenout;
2024	}
2025
2026#ifdef CONFIG_NET_RX_BUSY_POLL
2027	case SO_INCOMING_NAPI_ID:
2028		v.val = READ_ONCE(sk->sk_napi_id);
2029
2030		/* aggregate non-NAPI IDs down to 0 */
2031		if (v.val < MIN_NAPI_ID)
2032			v.val = 0;
2033
2034		break;
2035#endif
2036
2037	case SO_COOKIE:
2038		lv = sizeof(u64);
2039		if (len < lv)
2040			return -EINVAL;
2041		v.val64 = sock_gen_cookie(sk);
2042		break;
2043
2044	case SO_ZEROCOPY:
2045		v.val = sock_flag(sk, SOCK_ZEROCOPY);
2046		break;
2047
2048	case SO_TXTIME:
2049		lv = sizeof(v.txtime);
2050		v.txtime.clockid = sk->sk_clockid;
2051		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2052				  SOF_TXTIME_DEADLINE_MODE : 0;
2053		v.txtime.flags |= sk->sk_txtime_report_errors ?
2054				  SOF_TXTIME_REPORT_ERRORS : 0;
2055		break;
2056
2057	case SO_BINDTOIFINDEX:
2058		v.val = READ_ONCE(sk->sk_bound_dev_if);
2059		break;
2060
2061	case SO_NETNS_COOKIE:
2062		lv = sizeof(u64);
2063		if (len != lv)
2064			return -EINVAL;
2065		v.val64 = sock_net(sk)->net_cookie;
2066		break;
2067
2068	case SO_BUF_LOCK:
2069		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2070		break;
2071
2072	case SO_RESERVE_MEM:
2073		v.val = READ_ONCE(sk->sk_reserved_mem);
2074		break;
2075
2076	case SO_TXREHASH:
2077		/* Paired with WRITE_ONCE() in sk_setsockopt() */
2078		v.val = READ_ONCE(sk->sk_txrehash);
2079		break;
2080
2081	default:
2082		/* We implement the SO_SNDLOWAT etc to not be settable
2083		 * (1003.1g 7).
2084		 */
2085		return -ENOPROTOOPT;
2086	}
2087
2088	if (len > lv)
2089		len = lv;
2090	if (copy_to_sockptr(optval, &v, len))
2091		return -EFAULT;
2092lenout:
2093	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2094		return -EFAULT;
2095	return 0;
2096}
2097
2098/*
2099 * Initialize an sk_lock.
2100 *
2101 * (We also register the sk_lock with the lock validator.)
2102 */
2103static inline void sock_lock_init(struct sock *sk)
2104{
2105	if (sk->sk_kern_sock)
2106		sock_lock_init_class_and_name(
2107			sk,
2108			af_family_kern_slock_key_strings[sk->sk_family],
2109			af_family_kern_slock_keys + sk->sk_family,
2110			af_family_kern_key_strings[sk->sk_family],
2111			af_family_kern_keys + sk->sk_family);
2112	else
2113		sock_lock_init_class_and_name(
2114			sk,
2115			af_family_slock_key_strings[sk->sk_family],
2116			af_family_slock_keys + sk->sk_family,
2117			af_family_key_strings[sk->sk_family],
2118			af_family_keys + sk->sk_family);
2119}
2120
2121/*
2122 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2123 * even temporarily, because of RCU lookups. sk_node should also be left as is.
2124 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2125 */
2126static void sock_copy(struct sock *nsk, const struct sock *osk)
2127{
2128	const struct proto *prot = READ_ONCE(osk->sk_prot);
2129#ifdef CONFIG_SECURITY_NETWORK
2130	void *sptr = nsk->sk_security;
2131#endif
2132
2133	/* If we move sk_tx_queue_mapping out of the private section,
2134	 * we must check if sk_tx_queue_clear() is called after
2135	 * sock_copy() in sk_clone_lock().
2136	 */
2137	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2138		     offsetof(struct sock, sk_dontcopy_begin) ||
2139		     offsetof(struct sock, sk_tx_queue_mapping) >=
2140		     offsetof(struct sock, sk_dontcopy_end));
2141
2142	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2143
2144	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2145		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2146		      /* alloc is larger than struct, see sk_prot_alloc() */);
2147
2148#ifdef CONFIG_SECURITY_NETWORK
2149	nsk->sk_security = sptr;
2150	security_sk_clone(osk, nsk);
2151#endif
2152}
2153
2154static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2155		int family)
2156{
2157	struct sock *sk;
2158	struct kmem_cache *slab;
2159
2160	slab = prot->slab;
2161	if (slab != NULL) {
2162		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2163		if (!sk)
2164			return sk;
2165		if (want_init_on_alloc(priority))
2166			sk_prot_clear_nulls(sk, prot->obj_size);
2167	} else
2168		sk = kmalloc(prot->obj_size, priority);
2169
2170	if (sk != NULL) {
2171		if (security_sk_alloc(sk, family, priority))
2172			goto out_free;
2173
2174		if (!try_module_get(prot->owner))
2175			goto out_free_sec;
 
2176	}
2177
2178	return sk;
2179
2180out_free_sec:
2181	security_sk_free(sk);
2182out_free:
2183	if (slab != NULL)
2184		kmem_cache_free(slab, sk);
2185	else
2186		kfree(sk);
2187	return NULL;
2188}
2189
2190static void sk_prot_free(struct proto *prot, struct sock *sk)
2191{
2192	struct kmem_cache *slab;
2193	struct module *owner;
2194
2195	owner = prot->owner;
2196	slab = prot->slab;
2197
2198	cgroup_sk_free(&sk->sk_cgrp_data);
2199	mem_cgroup_sk_free(sk);
2200	security_sk_free(sk);
2201	if (slab != NULL)
2202		kmem_cache_free(slab, sk);
2203	else
2204		kfree(sk);
2205	module_put(owner);
2206}
2207
2208/**
2209 *	sk_alloc - All socket objects are allocated here
2210 *	@net: the applicable net namespace
2211 *	@family: protocol family
2212 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2213 *	@prot: struct proto associated with this new sock instance
2214 *	@kern: is this to be a kernel socket?
2215 */
2216struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2217		      struct proto *prot, int kern)
2218{
2219	struct sock *sk;
2220
2221	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2222	if (sk) {
2223		sk->sk_family = family;
2224		/*
2225		 * See comment in struct sock definition to understand
2226		 * why we need sk_prot_creator -acme
2227		 */
2228		sk->sk_prot = sk->sk_prot_creator = prot;
2229		sk->sk_kern_sock = kern;
2230		sock_lock_init(sk);
2231		sk->sk_net_refcnt = kern ? 0 : 1;
2232		if (likely(sk->sk_net_refcnt)) {
2233			get_net_track(net, &sk->ns_tracker, priority);
2234			sock_inuse_add(net, 1);
2235		} else {
2236			net_passive_inc(net);
2237			__netns_tracker_alloc(net, &sk->ns_tracker,
2238					      false, priority);
2239		}
2240
2241		sock_net_set(sk, net);
2242		refcount_set(&sk->sk_wmem_alloc, 1);
2243
2244		mem_cgroup_sk_alloc(sk);
2245		cgroup_sk_alloc(&sk->sk_cgrp_data);
2246		sock_update_classid(&sk->sk_cgrp_data);
2247		sock_update_netprioidx(&sk->sk_cgrp_data);
2248		sk_tx_queue_clear(sk);
2249	}
2250
2251	return sk;
2252}
2253EXPORT_SYMBOL(sk_alloc);
2254
2255/* Sockets having SOCK_RCU_FREE will call this function after one RCU
2256 * grace period. This is the case for UDP sockets and TCP listeners.
2257 */
2258static void __sk_destruct(struct rcu_head *head)
2259{
2260	struct sock *sk = container_of(head, struct sock, sk_rcu);
2261	struct net *net = sock_net(sk);
2262	struct sk_filter *filter;
2263
2264	if (sk->sk_destruct)
2265		sk->sk_destruct(sk);
2266
2267	filter = rcu_dereference_check(sk->sk_filter,
2268				       refcount_read(&sk->sk_wmem_alloc) == 0);
2269	if (filter) {
2270		sk_filter_uncharge(sk, filter);
2271		RCU_INIT_POINTER(sk->sk_filter, NULL);
2272	}
 
 
2273
2274	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2275
2276#ifdef CONFIG_BPF_SYSCALL
2277	bpf_sk_storage_free(sk);
2278#endif
2279
2280	if (atomic_read(&sk->sk_omem_alloc))
2281		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2282			 __func__, atomic_read(&sk->sk_omem_alloc));
2283
2284	if (sk->sk_frag.page) {
2285		put_page(sk->sk_frag.page);
2286		sk->sk_frag.page = NULL;
2287	}
2288
2289	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2290	put_cred(sk->sk_peer_cred);
2291	put_pid(sk->sk_peer_pid);
2292
2293	if (likely(sk->sk_net_refcnt)) {
2294		put_net_track(net, &sk->ns_tracker);
2295	} else {
2296		__netns_tracker_free(net, &sk->ns_tracker, false);
2297		net_passive_dec(net);
2298	}
2299	sk_prot_free(sk->sk_prot_creator, sk);
2300}
2301
2302void sk_net_refcnt_upgrade(struct sock *sk)
2303{
2304	struct net *net = sock_net(sk);
2305
2306	WARN_ON_ONCE(sk->sk_net_refcnt);
2307	__netns_tracker_free(net, &sk->ns_tracker, false);
2308	net_passive_dec(net);
2309	sk->sk_net_refcnt = 1;
2310	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2311	sock_inuse_add(net, 1);
2312}
2313EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2314
2315void sk_destruct(struct sock *sk)
2316{
2317	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2318
2319	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2320		reuseport_detach_sock(sk);
2321		use_call_rcu = true;
2322	}
2323
2324	if (use_call_rcu)
2325		call_rcu(&sk->sk_rcu, __sk_destruct);
2326	else
2327		__sk_destruct(&sk->sk_rcu);
2328}
2329
2330static void __sk_free(struct sock *sk)
2331{
2332	if (likely(sk->sk_net_refcnt))
2333		sock_inuse_add(sock_net(sk), -1);
2334
2335	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2336		sock_diag_broadcast_destroy(sk);
2337	else
2338		sk_destruct(sk);
2339}
2340
2341void sk_free(struct sock *sk)
2342{
2343	/*
2344	 * We subtract one from sk_wmem_alloc and can know if
2345	 * some packets are still in some tx queue.
2346	 * If not null, sock_wfree() will call __sk_free(sk) later
2347	 */
2348	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2349		__sk_free(sk);
2350}
2351EXPORT_SYMBOL(sk_free);
2352
2353static void sk_init_common(struct sock *sk)
2354{
2355	skb_queue_head_init(&sk->sk_receive_queue);
2356	skb_queue_head_init(&sk->sk_write_queue);
2357	skb_queue_head_init(&sk->sk_error_queue);
2358
2359	rwlock_init(&sk->sk_callback_lock);
2360	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2361			af_rlock_keys + sk->sk_family,
2362			af_family_rlock_key_strings[sk->sk_family]);
2363	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2364			af_wlock_keys + sk->sk_family,
2365			af_family_wlock_key_strings[sk->sk_family]);
2366	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2367			af_elock_keys + sk->sk_family,
2368			af_family_elock_key_strings[sk->sk_family]);
2369	if (sk->sk_kern_sock)
2370		lockdep_set_class_and_name(&sk->sk_callback_lock,
2371			af_kern_callback_keys + sk->sk_family,
2372			af_family_kern_clock_key_strings[sk->sk_family]);
2373	else
2374		lockdep_set_class_and_name(&sk->sk_callback_lock,
2375			af_callback_keys + sk->sk_family,
2376			af_family_clock_key_strings[sk->sk_family]);
2377}
2378
2379/**
2380 *	sk_clone_lock - clone a socket, and lock its clone
2381 *	@sk: the socket to clone
2382 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2383 *
2384 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2385 */
2386struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2387{
2388	struct proto *prot = READ_ONCE(sk->sk_prot);
2389	struct sk_filter *filter;
2390	bool is_charged = true;
2391	struct sock *newsk;
 
2392
2393	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2394	if (!newsk)
2395		goto out;
2396
2397	sock_copy(newsk, sk);
2398
2399	newsk->sk_prot_creator = prot;
 
 
 
 
 
 
 
 
 
2400
2401	/* SANITY */
2402	if (likely(newsk->sk_net_refcnt)) {
2403		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2404		sock_inuse_add(sock_net(newsk), 1);
2405	} else {
2406		/* Kernel sockets are not elevating the struct net refcount.
2407		 * Instead, use a tracker to more easily detect if a layer
2408		 * is not properly dismantling its kernel sockets at netns
2409		 * destroy time.
2410		 */
2411		net_passive_inc(sock_net(newsk));
2412		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2413				      false, priority);
2414	}
2415	sk_node_init(&newsk->sk_node);
2416	sock_lock_init(newsk);
2417	bh_lock_sock(newsk);
2418	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2419	newsk->sk_backlog.len = 0;
2420
2421	atomic_set(&newsk->sk_rmem_alloc, 0);
2422
2423	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2424	refcount_set(&newsk->sk_wmem_alloc, 1);
2425
2426	atomic_set(&newsk->sk_omem_alloc, 0);
2427	sk_init_common(newsk);
2428
2429	newsk->sk_dst_cache	= NULL;
2430	newsk->sk_dst_pending_confirm = 0;
2431	newsk->sk_wmem_queued	= 0;
2432	newsk->sk_forward_alloc = 0;
2433	newsk->sk_reserved_mem  = 0;
2434	atomic_set(&newsk->sk_drops, 0);
2435	newsk->sk_send_head	= NULL;
2436	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2437	atomic_set(&newsk->sk_zckey, 0);
2438
2439	sock_reset_flag(newsk, SOCK_DONE);
2440
2441	/* sk->sk_memcg will be populated at accept() time */
2442	newsk->sk_memcg = NULL;
 
 
 
 
 
 
 
 
2443
2444	cgroup_sk_clone(&newsk->sk_cgrp_data);
 
 
 
 
 
 
 
 
 
 
 
2445
2446	rcu_read_lock();
2447	filter = rcu_dereference(sk->sk_filter);
2448	if (filter != NULL)
2449		/* though it's an empty new sock, the charging may fail
2450		 * if sysctl_optmem_max was changed between creation of
2451		 * original socket and cloning
2452		 */
2453		is_charged = sk_filter_charge(newsk, filter);
2454	RCU_INIT_POINTER(newsk->sk_filter, filter);
2455	rcu_read_unlock();
2456
2457	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2458		/* We need to make sure that we don't uncharge the new
2459		 * socket if we couldn't charge it in the first place
2460		 * as otherwise we uncharge the parent's filter.
2461		 */
2462		if (!is_charged)
2463			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2464		sk_free_unlock_clone(newsk);
2465		newsk = NULL;
2466		goto out;
2467	}
2468	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2469
2470	if (bpf_sk_storage_clone(sk, newsk)) {
2471		sk_free_unlock_clone(newsk);
2472		newsk = NULL;
2473		goto out;
2474	}
2475
2476	/* Clear sk_user_data if parent had the pointer tagged
2477	 * as not suitable for copying when cloning.
2478	 */
2479	if (sk_user_data_is_nocopy(newsk))
2480		newsk->sk_user_data = NULL;
2481
2482	newsk->sk_err	   = 0;
2483	newsk->sk_err_soft = 0;
2484	newsk->sk_priority = 0;
2485	newsk->sk_incoming_cpu = raw_smp_processor_id();
2486
2487	/* Before updating sk_refcnt, we must commit prior changes to memory
2488	 * (Documentation/RCU/rculist_nulls.rst for details)
2489	 */
2490	smp_wmb();
2491	refcount_set(&newsk->sk_refcnt, 2);
2492
2493	sk_set_socket(newsk, NULL);
2494	sk_tx_queue_clear(newsk);
2495	RCU_INIT_POINTER(newsk->sk_wq, NULL);
 
 
 
 
 
2496
2497	if (newsk->sk_prot->sockets_allocated)
2498		sk_sockets_allocated_inc(newsk);
2499
2500	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2501		net_enable_timestamp();
 
 
2502out:
2503	return newsk;
2504}
2505EXPORT_SYMBOL_GPL(sk_clone_lock);
2506
2507void sk_free_unlock_clone(struct sock *sk)
2508{
2509	/* It is still raw copy of parent, so invalidate
2510	 * destructor and make plain sk_free() */
2511	sk->sk_destruct = NULL;
2512	bh_unlock_sock(sk);
2513	sk_free(sk);
2514}
2515EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2516
2517static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2518{
2519	bool is_ipv6 = false;
2520	u32 max_size;
2521
2522#if IS_ENABLED(CONFIG_IPV6)
2523	is_ipv6 = (sk->sk_family == AF_INET6 &&
2524		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2525#endif
2526	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2527	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2528			READ_ONCE(dst->dev->gso_ipv4_max_size);
2529	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2530		max_size = GSO_LEGACY_MAX_SIZE;
2531
2532	return max_size - (MAX_TCP_HEADER + 1);
2533}
2534
2535void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2536{
2537	u32 max_segs = 1;
2538
2539	sk->sk_route_caps = dst->dev->features;
2540	if (sk_is_tcp(sk))
2541		sk->sk_route_caps |= NETIF_F_GSO;
2542	if (sk->sk_route_caps & NETIF_F_GSO)
2543		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2544	if (unlikely(sk->sk_gso_disabled))
2545		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2546	if (sk_can_gso(sk)) {
2547		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2548			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2549		} else {
2550			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2551			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2552			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2553			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2554		}
2555	}
2556	sk->sk_gso_max_segs = max_segs;
2557	sk_dst_set(sk, dst);
2558}
2559EXPORT_SYMBOL_GPL(sk_setup_caps);
2560
2561/*
2562 *	Simple resource managers for sockets.
2563 */
2564
2565
2566/*
2567 * Write buffer destructor automatically called from kfree_skb.
2568 */
2569void sock_wfree(struct sk_buff *skb)
2570{
2571	struct sock *sk = skb->sk;
2572	unsigned int len = skb->truesize;
2573	bool free;
2574
2575	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2576		if (sock_flag(sk, SOCK_RCU_FREE) &&
2577		    sk->sk_write_space == sock_def_write_space) {
2578			rcu_read_lock();
2579			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2580			sock_def_write_space_wfree(sk);
2581			rcu_read_unlock();
2582			if (unlikely(free))
2583				__sk_free(sk);
2584			return;
2585		}
2586
2587		/*
2588		 * Keep a reference on sk_wmem_alloc, this will be released
2589		 * after sk_write_space() call
2590		 */
2591		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2592		sk->sk_write_space(sk);
2593		len = 1;
2594	}
2595	/*
2596	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2597	 * could not do because of in-flight packets
2598	 */
2599	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2600		__sk_free(sk);
2601}
2602EXPORT_SYMBOL(sock_wfree);
2603
2604/* This variant of sock_wfree() is used by TCP,
2605 * since it sets SOCK_USE_WRITE_QUEUE.
2606 */
2607void __sock_wfree(struct sk_buff *skb)
2608{
2609	struct sock *sk = skb->sk;
2610
2611	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2612		__sk_free(sk);
2613}
2614
2615void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2616{
2617	skb_orphan(skb);
 
2618#ifdef CONFIG_INET
2619	if (unlikely(!sk_fullsock(sk)))
2620		return skb_set_owner_edemux(skb, sk);
 
 
 
2621#endif
2622	skb->sk = sk;
2623	skb->destructor = sock_wfree;
2624	skb_set_hash_from_sk(skb, sk);
2625	/*
2626	 * We used to take a refcount on sk, but following operation
2627	 * is enough to guarantee sk_free() won't free this sock until
2628	 * all in-flight packets are completed
2629	 */
2630	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2631}
2632EXPORT_SYMBOL(skb_set_owner_w);
2633
2634static bool can_skb_orphan_partial(const struct sk_buff *skb)
2635{
2636	/* Drivers depend on in-order delivery for crypto offload,
2637	 * partial orphan breaks out-of-order-OK logic.
2638	 */
2639	if (skb_is_decrypted(skb))
2640		return false;
2641
2642	return (skb->destructor == sock_wfree ||
2643		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2644}
2645
2646/* This helper is used by netem, as it can hold packets in its
2647 * delay queue. We want to allow the owner socket to send more
2648 * packets, as if they were already TX completed by a typical driver.
2649 * But we also want to keep skb->sk set because some packet schedulers
2650 * rely on it (sch_fq for example).
2651 */
2652void skb_orphan_partial(struct sk_buff *skb)
2653{
2654	if (skb_is_tcp_pure_ack(skb))
2655		return;
2656
2657	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2658		return;
 
 
 
 
2659
2660	skb_orphan(skb);
 
 
 
 
 
 
2661}
2662EXPORT_SYMBOL(skb_orphan_partial);
2663
2664/*
2665 * Read buffer destructor automatically called from kfree_skb.
2666 */
2667void sock_rfree(struct sk_buff *skb)
2668{
2669	struct sock *sk = skb->sk;
2670	unsigned int len = skb->truesize;
2671
2672	atomic_sub(len, &sk->sk_rmem_alloc);
2673	sk_mem_uncharge(sk, len);
2674}
2675EXPORT_SYMBOL(sock_rfree);
2676
2677/*
2678 * Buffer destructor for skbs that are not used directly in read or write
2679 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2680 */
2681void sock_efree(struct sk_buff *skb)
2682{
2683	sock_put(skb->sk);
2684}
2685EXPORT_SYMBOL(sock_efree);
2686
2687/* Buffer destructor for prefetch/receive path where reference count may
2688 * not be held, e.g. for listen sockets.
2689 */
2690#ifdef CONFIG_INET
2691void sock_pfree(struct sk_buff *skb)
2692{
2693	struct sock *sk = skb->sk;
2694
2695	if (!sk_is_refcounted(sk))
2696		return;
2697
2698	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2699		inet_reqsk(sk)->rsk_listener = NULL;
2700		reqsk_free(inet_reqsk(sk));
2701		return;
2702	}
2703
2704	sock_gen_put(sk);
2705}
2706EXPORT_SYMBOL(sock_pfree);
2707#endif /* CONFIG_INET */
2708
2709kuid_t sock_i_uid(struct sock *sk)
2710{
2711	kuid_t uid;
2712
2713	read_lock_bh(&sk->sk_callback_lock);
2714	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2715	read_unlock_bh(&sk->sk_callback_lock);
2716	return uid;
2717}
2718EXPORT_SYMBOL(sock_i_uid);
2719
2720unsigned long __sock_i_ino(struct sock *sk)
2721{
2722	unsigned long ino;
2723
2724	read_lock(&sk->sk_callback_lock);
2725	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2726	read_unlock(&sk->sk_callback_lock);
2727	return ino;
2728}
2729EXPORT_SYMBOL(__sock_i_ino);
2730
2731unsigned long sock_i_ino(struct sock *sk)
2732{
2733	unsigned long ino;
2734
2735	local_bh_disable();
2736	ino = __sock_i_ino(sk);
2737	local_bh_enable();
2738	return ino;
2739}
2740EXPORT_SYMBOL(sock_i_ino);
2741
2742/*
2743 * Allocate a skb from the socket's send buffer.
2744 */
2745struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2746			     gfp_t priority)
2747{
2748	if (force ||
2749	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2750		struct sk_buff *skb = alloc_skb(size, priority);
2751
2752		if (skb) {
2753			skb_set_owner_w(skb, sk);
2754			return skb;
2755		}
2756	}
2757	return NULL;
2758}
2759EXPORT_SYMBOL(sock_wmalloc);
2760
2761static void sock_ofree(struct sk_buff *skb)
2762{
2763	struct sock *sk = skb->sk;
2764
2765	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2766}
2767
2768struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2769			     gfp_t priority)
2770{
2771	struct sk_buff *skb;
2772
2773	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2774	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2775	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2776		return NULL;
2777
2778	skb = alloc_skb(size, priority);
2779	if (!skb)
2780		return NULL;
2781
2782	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2783	skb->sk = sk;
2784	skb->destructor = sock_ofree;
2785	return skb;
2786}
2787
2788/*
2789 * Allocate a memory block from the socket's option memory buffer.
2790 */
2791void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2792{
2793	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2794
2795	if ((unsigned int)size <= optmem_max &&
2796	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2797		void *mem;
2798		/* First do the add, to avoid the race if kmalloc
2799		 * might sleep.
2800		 */
2801		atomic_add(size, &sk->sk_omem_alloc);
2802		mem = kmalloc(size, priority);
2803		if (mem)
2804			return mem;
2805		atomic_sub(size, &sk->sk_omem_alloc);
2806	}
2807	return NULL;
2808}
2809EXPORT_SYMBOL(sock_kmalloc);
2810
2811/* Free an option memory block. Note, we actually want the inline
2812 * here as this allows gcc to detect the nullify and fold away the
2813 * condition entirely.
2814 */
2815static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2816				  const bool nullify)
2817{
2818	if (WARN_ON_ONCE(!mem))
2819		return;
2820	if (nullify)
2821		kfree_sensitive(mem);
2822	else
2823		kfree(mem);
2824	atomic_sub(size, &sk->sk_omem_alloc);
2825}
2826
2827void sock_kfree_s(struct sock *sk, void *mem, int size)
2828{
2829	__sock_kfree_s(sk, mem, size, false);
2830}
2831EXPORT_SYMBOL(sock_kfree_s);
2832
2833void sock_kzfree_s(struct sock *sk, void *mem, int size)
2834{
2835	__sock_kfree_s(sk, mem, size, true);
2836}
2837EXPORT_SYMBOL(sock_kzfree_s);
2838
2839/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2840   I think, these locks should be removed for datagram sockets.
2841 */
2842static long sock_wait_for_wmem(struct sock *sk, long timeo)
2843{
2844	DEFINE_WAIT(wait);
2845
2846	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2847	for (;;) {
2848		if (!timeo)
2849			break;
2850		if (signal_pending(current))
2851			break;
2852		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2853		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2854		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2855			break;
2856		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2857			break;
2858		if (READ_ONCE(sk->sk_err))
2859			break;
2860		timeo = schedule_timeout(timeo);
2861	}
2862	finish_wait(sk_sleep(sk), &wait);
2863	return timeo;
2864}
2865
2866
2867/*
2868 *	Generic send/receive buffer handlers
2869 */
2870
2871struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2872				     unsigned long data_len, int noblock,
2873				     int *errcode, int max_page_order)
2874{
2875	struct sk_buff *skb;
2876	long timeo;
2877	int err;
2878
2879	timeo = sock_sndtimeo(sk, noblock);
2880	for (;;) {
2881		err = sock_error(sk);
2882		if (err != 0)
2883			goto failure;
2884
2885		err = -EPIPE;
2886		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2887			goto failure;
2888
2889		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2890			break;
2891
2892		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2893		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2894		err = -EAGAIN;
2895		if (!timeo)
2896			goto failure;
2897		if (signal_pending(current))
2898			goto interrupted;
2899		timeo = sock_wait_for_wmem(sk, timeo);
2900	}
2901	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2902				   errcode, sk->sk_allocation);
2903	if (skb)
2904		skb_set_owner_w(skb, sk);
2905	return skb;
2906
2907interrupted:
2908	err = sock_intr_errno(timeo);
2909failure:
2910	*errcode = err;
2911	return NULL;
2912}
2913EXPORT_SYMBOL(sock_alloc_send_pskb);
2914
2915int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
 
 
 
 
 
 
 
2916		     struct sockcm_cookie *sockc)
2917{
2918	u32 tsflags;
2919
2920	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
2921
2922	switch (cmsg->cmsg_type) {
2923	case SO_MARK:
2924		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2925		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2926			return -EPERM;
2927		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2928			return -EINVAL;
2929		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2930		break;
2931	case SO_TIMESTAMPING_OLD:
2932	case SO_TIMESTAMPING_NEW:
2933		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2934			return -EINVAL;
2935
2936		tsflags = *(u32 *)CMSG_DATA(cmsg);
2937		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2938			return -EINVAL;
2939
2940		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2941		sockc->tsflags |= tsflags;
2942		break;
2943	case SCM_TXTIME:
2944		if (!sock_flag(sk, SOCK_TXTIME))
2945			return -EINVAL;
2946		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2947			return -EINVAL;
2948		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2949		break;
2950	case SCM_TS_OPT_ID:
2951		if (sk_is_tcp(sk))
2952			return -EINVAL;
2953		tsflags = READ_ONCE(sk->sk_tsflags);
2954		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
2955			return -EINVAL;
2956		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2957			return -EINVAL;
2958		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
2959		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
2960		break;
2961	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2962	case SCM_RIGHTS:
2963	case SCM_CREDENTIALS:
2964		break;
2965	default:
2966		return -EINVAL;
2967	}
2968	return 0;
2969}
2970EXPORT_SYMBOL(__sock_cmsg_send);
2971
2972int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2973		   struct sockcm_cookie *sockc)
2974{
2975	struct cmsghdr *cmsg;
2976	int ret;
2977
2978	for_each_cmsghdr(cmsg, msg) {
2979		if (!CMSG_OK(msg, cmsg))
2980			return -EINVAL;
2981		if (cmsg->cmsg_level != SOL_SOCKET)
2982			continue;
2983		ret = __sock_cmsg_send(sk, cmsg, sockc);
2984		if (ret)
2985			return ret;
2986	}
2987	return 0;
2988}
2989EXPORT_SYMBOL(sock_cmsg_send);
2990
2991static void sk_enter_memory_pressure(struct sock *sk)
2992{
2993	if (!sk->sk_prot->enter_memory_pressure)
2994		return;
2995
2996	sk->sk_prot->enter_memory_pressure(sk);
2997}
2998
2999static void sk_leave_memory_pressure(struct sock *sk)
3000{
3001	if (sk->sk_prot->leave_memory_pressure) {
3002		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3003				     tcp_leave_memory_pressure, sk);
3004	} else {
3005		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3006
3007		if (memory_pressure && READ_ONCE(*memory_pressure))
3008			WRITE_ONCE(*memory_pressure, 0);
3009	}
3010}
3011
3012DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
 
3013
3014/**
3015 * skb_page_frag_refill - check that a page_frag contains enough room
3016 * @sz: minimum size of the fragment we want to get
3017 * @pfrag: pointer to page_frag
3018 * @gfp: priority for memory allocation
3019 *
3020 * Note: While this allocator tries to use high order pages, there is
3021 * no guarantee that allocations succeed. Therefore, @sz MUST be
3022 * less or equal than PAGE_SIZE.
3023 */
3024bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3025{
3026	if (pfrag->page) {
3027		if (page_ref_count(pfrag->page) == 1) {
3028			pfrag->offset = 0;
3029			return true;
3030		}
3031		if (pfrag->offset + sz <= pfrag->size)
3032			return true;
3033		put_page(pfrag->page);
3034	}
3035
3036	pfrag->offset = 0;
3037	if (SKB_FRAG_PAGE_ORDER &&
3038	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3039		/* Avoid direct reclaim but allow kswapd to wake */
3040		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3041					  __GFP_COMP | __GFP_NOWARN |
3042					  __GFP_NORETRY,
3043					  SKB_FRAG_PAGE_ORDER);
3044		if (likely(pfrag->page)) {
3045			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3046			return true;
3047		}
3048	}
3049	pfrag->page = alloc_page(gfp);
3050	if (likely(pfrag->page)) {
3051		pfrag->size = PAGE_SIZE;
3052		return true;
3053	}
3054	return false;
3055}
3056EXPORT_SYMBOL(skb_page_frag_refill);
3057
3058bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3059{
3060	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3061		return true;
3062
3063	sk_enter_memory_pressure(sk);
3064	sk_stream_moderate_sndbuf(sk);
3065	return false;
3066}
3067EXPORT_SYMBOL(sk_page_frag_refill);
3068
3069void __lock_sock(struct sock *sk)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3070	__releases(&sk->sk_lock.slock)
3071	__acquires(&sk->sk_lock.slock)
3072{
3073	DEFINE_WAIT(wait);
3074
3075	for (;;) {
3076		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3077					TASK_UNINTERRUPTIBLE);
3078		spin_unlock_bh(&sk->sk_lock.slock);
3079		schedule();
3080		spin_lock_bh(&sk->sk_lock.slock);
3081		if (!sock_owned_by_user(sk))
3082			break;
3083	}
3084	finish_wait(&sk->sk_lock.wq, &wait);
3085}
3086
3087void __release_sock(struct sock *sk)
3088	__releases(&sk->sk_lock.slock)
3089	__acquires(&sk->sk_lock.slock)
3090{
3091	struct sk_buff *skb, *next;
3092
3093	while ((skb = sk->sk_backlog.head) != NULL) {
3094		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3095
3096		spin_unlock_bh(&sk->sk_lock.slock);
3097
3098		do {
3099			next = skb->next;
3100			prefetch(next);
3101			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3102			skb_mark_not_on_list(skb);
3103			sk_backlog_rcv(sk, skb);
3104
3105			cond_resched();
3106
3107			skb = next;
3108		} while (skb != NULL);
3109
3110		spin_lock_bh(&sk->sk_lock.slock);
3111	}
3112
3113	/*
3114	 * Doing the zeroing here guarantee we can not loop forever
3115	 * while a wild producer attempts to flood us.
3116	 */
3117	sk->sk_backlog.len = 0;
3118}
3119
3120void __sk_flush_backlog(struct sock *sk)
3121{
3122	spin_lock_bh(&sk->sk_lock.slock);
3123	__release_sock(sk);
3124
3125	if (sk->sk_prot->release_cb)
3126		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3127				     tcp_release_cb, sk);
3128
3129	spin_unlock_bh(&sk->sk_lock.slock);
3130}
3131EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3132
3133/**
3134 * sk_wait_data - wait for data to arrive at sk_receive_queue
3135 * @sk:    sock to wait on
3136 * @timeo: for how long
3137 * @skb:   last skb seen on sk_receive_queue
3138 *
3139 * Now socket state including sk->sk_err is changed only under lock,
3140 * hence we may omit checks after joining wait queue.
3141 * We check receive queue before schedule() only as optimization;
3142 * it is very likely that release_sock() added new data.
3143 */
3144int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3145{
3146	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3147	int rc;
3148
3149	add_wait_queue(sk_sleep(sk), &wait);
3150	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3151	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3152	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3153	remove_wait_queue(sk_sleep(sk), &wait);
3154	return rc;
3155}
3156EXPORT_SYMBOL(sk_wait_data);
3157
3158/**
3159 *	__sk_mem_raise_allocated - increase memory_allocated
3160 *	@sk: socket
3161 *	@size: memory size to allocate
3162 *	@amt: pages to allocate
3163 *	@kind: allocation type
3164 *
3165 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3166 *
3167 *	Unlike the globally shared limits among the sockets under same protocol,
3168 *	consuming the budget of a memcg won't have direct effect on other ones.
3169 *	So be optimistic about memcg's tolerance, and leave the callers to decide
3170 *	whether or not to raise allocated through sk_under_memory_pressure() or
3171 *	its variants.
3172 */
3173int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3174{
3175	struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3176	struct proto *prot = sk->sk_prot;
3177	bool charged = false;
3178	long allocated;
3179
3180	sk_memory_allocated_add(sk, amt);
3181	allocated = sk_memory_allocated(sk);
3182
3183	if (memcg) {
3184		if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3185			goto suppress_allocation;
3186		charged = true;
3187	}
3188
3189	/* Under limit. */
3190	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3191		sk_leave_memory_pressure(sk);
3192		return 1;
3193	}
3194
3195	/* Under pressure. */
3196	if (allocated > sk_prot_mem_limits(sk, 1))
3197		sk_enter_memory_pressure(sk);
3198
3199	/* Over hard limit. */
3200	if (allocated > sk_prot_mem_limits(sk, 2))
3201		goto suppress_allocation;
3202
3203	/* Guarantee minimum buffer size under pressure (either global
3204	 * or memcg) to make sure features described in RFC 7323 (TCP
3205	 * Extensions for High Performance) work properly.
3206	 *
3207	 * This rule does NOT stand when exceeds global or memcg's hard
3208	 * limit, or else a DoS attack can be taken place by spawning
3209	 * lots of sockets whose usage are under minimum buffer size.
3210	 */
3211	if (kind == SK_MEM_RECV) {
3212		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3213			return 1;
3214
3215	} else { /* SK_MEM_SEND */
3216		int wmem0 = sk_get_wmem0(sk, prot);
3217
3218		if (sk->sk_type == SOCK_STREAM) {
3219			if (sk->sk_wmem_queued < wmem0)
3220				return 1;
3221		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3222				return 1;
3223		}
3224	}
3225
3226	if (sk_has_memory_pressure(sk)) {
3227		u64 alloc;
3228
3229		/* The following 'average' heuristic is within the
3230		 * scope of global accounting, so it only makes
3231		 * sense for global memory pressure.
3232		 */
3233		if (!sk_under_global_memory_pressure(sk))
3234			return 1;
3235
3236		/* Try to be fair among all the sockets under global
3237		 * pressure by allowing the ones that below average
3238		 * usage to raise.
3239		 */
3240		alloc = sk_sockets_allocated_read_positive(sk);
3241		if (sk_prot_mem_limits(sk, 2) > alloc *
3242		    sk_mem_pages(sk->sk_wmem_queued +
3243				 atomic_read(&sk->sk_rmem_alloc) +
3244				 sk->sk_forward_alloc))
3245			return 1;
3246	}
3247
3248suppress_allocation:
3249
3250	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3251		sk_stream_moderate_sndbuf(sk);
3252
3253		/* Fail only if socket is _under_ its sndbuf.
3254		 * In this case we cannot block, so that we have to fail.
3255		 */
3256		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3257			/* Force charge with __GFP_NOFAIL */
3258			if (memcg && !charged) {
3259				mem_cgroup_charge_skmem(memcg, amt,
3260					gfp_memcg_charge() | __GFP_NOFAIL);
3261			}
3262			return 1;
3263		}
3264	}
3265
3266	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3267		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3268
3269	sk_memory_allocated_sub(sk, amt);
3270
3271	if (charged)
3272		mem_cgroup_uncharge_skmem(memcg, amt);
3273
3274	return 0;
3275}
 
3276
3277/**
3278 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3279 *	@sk: socket
3280 *	@size: memory size to allocate
3281 *	@kind: allocation type
3282 *
3283 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3284 *	rmem allocation. This function assumes that protocols which have
3285 *	memory_pressure use sk_wmem_queued as write buffer accounting.
3286 */
3287int __sk_mem_schedule(struct sock *sk, int size, int kind)
3288{
3289	int ret, amt = sk_mem_pages(size);
3290
3291	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3292	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3293	if (!ret)
3294		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3295	return ret;
3296}
3297EXPORT_SYMBOL(__sk_mem_schedule);
3298
3299/**
3300 *	__sk_mem_reduce_allocated - reclaim memory_allocated
3301 *	@sk: socket
3302 *	@amount: number of quanta
3303 *
3304 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3305 */
3306void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3307{
3308	sk_memory_allocated_sub(sk, amount);
3309
3310	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3311		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3312
3313	if (sk_under_global_memory_pressure(sk) &&
3314	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3315		sk_leave_memory_pressure(sk);
3316}
 
3317
3318/**
3319 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3320 *	@sk: socket
3321 *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3322 */
3323void __sk_mem_reclaim(struct sock *sk, int amount)
3324{
3325	amount >>= PAGE_SHIFT;
3326	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3327	__sk_mem_reduce_allocated(sk, amount);
3328}
3329EXPORT_SYMBOL(__sk_mem_reclaim);
3330
3331int sk_set_peek_off(struct sock *sk, int val)
3332{
3333	WRITE_ONCE(sk->sk_peek_off, val);
3334	return 0;
3335}
3336EXPORT_SYMBOL_GPL(sk_set_peek_off);
3337
3338/*
3339 * Set of default routines for initialising struct proto_ops when
3340 * the protocol does not support a particular function. In certain
3341 * cases where it makes no sense for a protocol to have a "do nothing"
3342 * function, some default processing is provided.
3343 */
3344
3345int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3346{
3347	return -EOPNOTSUPP;
3348}
3349EXPORT_SYMBOL(sock_no_bind);
3350
3351int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3352		    int len, int flags)
3353{
3354	return -EOPNOTSUPP;
3355}
3356EXPORT_SYMBOL(sock_no_connect);
3357
3358int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3359{
3360	return -EOPNOTSUPP;
3361}
3362EXPORT_SYMBOL(sock_no_socketpair);
3363
3364int sock_no_accept(struct socket *sock, struct socket *newsock,
3365		   struct proto_accept_arg *arg)
3366{
3367	return -EOPNOTSUPP;
3368}
3369EXPORT_SYMBOL(sock_no_accept);
3370
3371int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3372		    int peer)
3373{
3374	return -EOPNOTSUPP;
3375}
3376EXPORT_SYMBOL(sock_no_getname);
3377
 
 
 
 
 
 
3378int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3379{
3380	return -EOPNOTSUPP;
3381}
3382EXPORT_SYMBOL(sock_no_ioctl);
3383
3384int sock_no_listen(struct socket *sock, int backlog)
3385{
3386	return -EOPNOTSUPP;
3387}
3388EXPORT_SYMBOL(sock_no_listen);
3389
3390int sock_no_shutdown(struct socket *sock, int how)
3391{
3392	return -EOPNOTSUPP;
3393}
3394EXPORT_SYMBOL(sock_no_shutdown);
3395
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3396int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3397{
3398	return -EOPNOTSUPP;
3399}
3400EXPORT_SYMBOL(sock_no_sendmsg);
3401
3402int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3403{
3404	return -EOPNOTSUPP;
3405}
3406EXPORT_SYMBOL(sock_no_sendmsg_locked);
3407
3408int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3409		    int flags)
3410{
3411	return -EOPNOTSUPP;
3412}
3413EXPORT_SYMBOL(sock_no_recvmsg);
3414
3415int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3416{
3417	/* Mirror missing mmap method error code */
3418	return -ENODEV;
3419}
3420EXPORT_SYMBOL(sock_no_mmap);
3421
3422/*
3423 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3424 * various sock-based usage counts.
3425 */
3426void __receive_sock(struct file *file)
3427{
3428	struct socket *sock;
 
 
 
 
 
 
 
 
 
 
3429
3430	sock = sock_from_file(file);
3431	if (sock) {
3432		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3433		sock_update_classid(&sock->sk->sk_cgrp_data);
3434	}
 
 
 
 
 
 
 
 
3435}
 
3436
3437/*
3438 *	Default Socket Callbacks
3439 */
3440
3441static void sock_def_wakeup(struct sock *sk)
3442{
3443	struct socket_wq *wq;
3444
3445	rcu_read_lock();
3446	wq = rcu_dereference(sk->sk_wq);
3447	if (skwq_has_sleeper(wq))
3448		wake_up_interruptible_all(&wq->wait);
3449	rcu_read_unlock();
3450}
3451
3452static void sock_def_error_report(struct sock *sk)
3453{
3454	struct socket_wq *wq;
3455
3456	rcu_read_lock();
3457	wq = rcu_dereference(sk->sk_wq);
3458	if (skwq_has_sleeper(wq))
3459		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3460	sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3461	rcu_read_unlock();
3462}
3463
3464void sock_def_readable(struct sock *sk)
3465{
3466	struct socket_wq *wq;
3467
3468	trace_sk_data_ready(sk);
3469
3470	rcu_read_lock();
3471	wq = rcu_dereference(sk->sk_wq);
3472	if (skwq_has_sleeper(wq))
3473		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3474						EPOLLRDNORM | EPOLLRDBAND);
3475	sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3476	rcu_read_unlock();
3477}
3478
3479static void sock_def_write_space(struct sock *sk)
3480{
3481	struct socket_wq *wq;
3482
3483	rcu_read_lock();
3484
3485	/* Do not wake up a writer until he can make "significant"
3486	 * progress.  --DaveM
3487	 */
3488	if (sock_writeable(sk)) {
3489		wq = rcu_dereference(sk->sk_wq);
3490		if (skwq_has_sleeper(wq))
3491			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3492						EPOLLWRNORM | EPOLLWRBAND);
3493
3494		/* Should agree with poll, otherwise some programs break */
3495		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
 
3496	}
3497
3498	rcu_read_unlock();
3499}
3500
3501/* An optimised version of sock_def_write_space(), should only be called
3502 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3503 * ->sk_wmem_alloc.
3504 */
3505static void sock_def_write_space_wfree(struct sock *sk)
3506{
3507	/* Do not wake up a writer until he can make "significant"
3508	 * progress.  --DaveM
3509	 */
3510	if (sock_writeable(sk)) {
3511		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3512
3513		/* rely on refcount_sub from sock_wfree() */
3514		smp_mb__after_atomic();
3515		if (wq && waitqueue_active(&wq->wait))
3516			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3517						EPOLLWRNORM | EPOLLWRBAND);
3518
3519		/* Should agree with poll, otherwise some programs break */
3520		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3521	}
3522}
3523
3524static void sock_def_destruct(struct sock *sk)
3525{
3526}
3527
3528void sk_send_sigurg(struct sock *sk)
3529{
3530	if (sk->sk_socket && sk->sk_socket->file)
3531		if (send_sigurg(sk->sk_socket->file))
3532			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3533}
3534EXPORT_SYMBOL(sk_send_sigurg);
3535
3536void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3537		    unsigned long expires)
3538{
3539	if (!mod_timer(timer, expires))
3540		sock_hold(sk);
3541}
3542EXPORT_SYMBOL(sk_reset_timer);
3543
3544void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3545{
3546	if (del_timer(timer))
3547		__sock_put(sk);
3548}
3549EXPORT_SYMBOL(sk_stop_timer);
3550
3551void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3552{
3553	if (del_timer_sync(timer))
3554		__sock_put(sk);
3555}
3556EXPORT_SYMBOL(sk_stop_timer_sync);
3557
3558void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3559{
3560	sk_init_common(sk);
3561	sk->sk_send_head	=	NULL;
3562
3563	timer_setup(&sk->sk_timer, NULL, 0);
3564
3565	sk->sk_allocation	=	GFP_KERNEL;
3566	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3567	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3568	sk->sk_state		=	TCP_CLOSE;
3569	sk->sk_use_task_frag	=	true;
3570	sk_set_socket(sk, sock);
3571
3572	sock_set_flag(sk, SOCK_ZAPPED);
3573
3574	if (sock) {
3575		sk->sk_type	=	sock->type;
3576		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3577		sock->sk	=	sk;
 
3578	} else {
3579		RCU_INIT_POINTER(sk->sk_wq, NULL);
 
3580	}
3581	sk->sk_uid	=	uid;
 
 
 
 
 
 
 
 
 
 
 
3582
3583	sk->sk_state_change	=	sock_def_wakeup;
3584	sk->sk_data_ready	=	sock_def_readable;
3585	sk->sk_write_space	=	sock_def_write_space;
3586	sk->sk_error_report	=	sock_def_error_report;
3587	sk->sk_destruct		=	sock_def_destruct;
3588
3589	sk->sk_frag.page	=	NULL;
3590	sk->sk_frag.offset	=	0;
3591	sk->sk_peek_off		=	-1;
3592
3593	sk->sk_peer_pid 	=	NULL;
3594	sk->sk_peer_cred	=	NULL;
3595	spin_lock_init(&sk->sk_peer_lock);
3596
3597	sk->sk_write_pending	=	0;
3598	sk->sk_rcvlowat		=	1;
3599	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3600	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3601
3602	sk->sk_stamp = SK_DEFAULT_STAMP;
3603#if BITS_PER_LONG==32
3604	seqlock_init(&sk->sk_stamp_seq);
3605#endif
3606	atomic_set(&sk->sk_zckey, 0);
3607
3608#ifdef CONFIG_NET_RX_BUSY_POLL
3609	sk->sk_napi_id		=	0;
3610	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3611#endif
3612
3613	sk->sk_max_pacing_rate = ~0UL;
3614	sk->sk_pacing_rate = ~0UL;
3615	WRITE_ONCE(sk->sk_pacing_shift, 10);
3616	sk->sk_incoming_cpu = -1;
3617
3618	sk_rx_queue_clear(sk);
3619	/*
3620	 * Before updating sk_refcnt, we must commit prior changes to memory
3621	 * (Documentation/RCU/rculist_nulls.rst for details)
3622	 */
3623	smp_wmb();
3624	refcount_set(&sk->sk_refcnt, 1);
3625	atomic_set(&sk->sk_drops, 0);
3626}
3627EXPORT_SYMBOL(sock_init_data_uid);
3628
3629void sock_init_data(struct socket *sock, struct sock *sk)
3630{
3631	kuid_t uid = sock ?
3632		SOCK_INODE(sock)->i_uid :
3633		make_kuid(sock_net(sk)->user_ns, 0);
3634
3635	sock_init_data_uid(sock, sk, uid);
3636}
3637EXPORT_SYMBOL(sock_init_data);
3638
3639void lock_sock_nested(struct sock *sk, int subclass)
3640{
3641	/* The sk_lock has mutex_lock() semantics here. */
3642	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3643
3644	might_sleep();
3645	spin_lock_bh(&sk->sk_lock.slock);
3646	if (sock_owned_by_user_nocheck(sk))
3647		__lock_sock(sk);
3648	sk->sk_lock.owned = 1;
3649	spin_unlock_bh(&sk->sk_lock.slock);
 
 
 
 
 
3650}
3651EXPORT_SYMBOL(lock_sock_nested);
3652
3653void release_sock(struct sock *sk)
3654{
3655	spin_lock_bh(&sk->sk_lock.slock);
3656	if (sk->sk_backlog.tail)
3657		__release_sock(sk);
3658
 
 
 
3659	if (sk->sk_prot->release_cb)
3660		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3661				     tcp_release_cb, sk);
3662
3663	sock_release_ownership(sk);
3664	if (waitqueue_active(&sk->sk_lock.wq))
3665		wake_up(&sk->sk_lock.wq);
3666	spin_unlock_bh(&sk->sk_lock.slock);
3667}
3668EXPORT_SYMBOL(release_sock);
3669
3670bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
 
 
 
 
 
 
 
 
 
 
 
 
 
3671{
3672	might_sleep();
3673	spin_lock_bh(&sk->sk_lock.slock);
3674
3675	if (!sock_owned_by_user_nocheck(sk)) {
3676		/*
3677		 * Fast path return with bottom halves disabled and
3678		 * sock::sk_lock.slock held.
3679		 *
3680		 * The 'mutex' is not contended and holding
3681		 * sock::sk_lock.slock prevents all other lockers to
3682		 * proceed so the corresponding unlock_sock_fast() can
3683		 * avoid the slow path of release_sock() completely and
3684		 * just release slock.
3685		 *
3686		 * From a semantical POV this is equivalent to 'acquiring'
3687		 * the 'mutex', hence the corresponding lockdep
3688		 * mutex_release() has to happen in the fast path of
3689		 * unlock_sock_fast().
3690		 */
3691		return false;
3692	}
3693
3694	__lock_sock(sk);
3695	sk->sk_lock.owned = 1;
3696	__acquire(&sk->sk_lock.slock);
3697	spin_unlock_bh(&sk->sk_lock.slock);
 
 
 
 
3698	return true;
3699}
3700EXPORT_SYMBOL(__lock_sock_fast);
3701
3702int sock_gettstamp(struct socket *sock, void __user *userstamp,
3703		   bool timeval, bool time32)
3704{
3705	struct sock *sk = sock->sk;
3706	struct timespec64 ts;
 
 
 
 
 
 
 
 
 
 
 
3707
3708	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3709	ts = ktime_to_timespec64(sock_read_timestamp(sk));
 
 
 
 
3710	if (ts.tv_sec == -1)
3711		return -ENOENT;
3712	if (ts.tv_sec == 0) {
3713		ktime_t kt = ktime_get_real();
3714		sock_write_timestamp(sk, kt);
3715		ts = ktime_to_timespec64(kt);
3716	}
3717
3718	if (timeval)
3719		ts.tv_nsec /= 1000;
3720
3721#ifdef CONFIG_COMPAT_32BIT_TIME
3722	if (time32)
3723		return put_old_timespec32(&ts, userstamp);
3724#endif
3725#ifdef CONFIG_SPARC64
3726	/* beware of padding in sparc64 timeval */
3727	if (timeval && !in_compat_syscall()) {
3728		struct __kernel_old_timeval __user tv = {
3729			.tv_sec = ts.tv_sec,
3730			.tv_usec = ts.tv_nsec,
3731		};
3732		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3733			return -EFAULT;
3734		return 0;
3735	}
3736#endif
3737	return put_timespec64(&ts, userstamp);
3738}
3739EXPORT_SYMBOL(sock_gettstamp);
3740
3741void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3742{
3743	if (!sock_flag(sk, flag)) {
3744		unsigned long previous_flags = sk->sk_flags;
3745
3746		sock_set_flag(sk, flag);
3747		/*
3748		 * we just set one of the two flags which require net
3749		 * time stamping, but time stamping might have been on
3750		 * already because of the other one
3751		 */
3752		if (sock_needs_netstamp(sk) &&
3753		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3754			net_enable_timestamp();
3755	}
3756}
3757
3758int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3759		       int level, int type)
3760{
3761	struct sock_exterr_skb *serr;
3762	struct sk_buff *skb;
3763	int copied, err;
3764
3765	err = -EAGAIN;
3766	skb = sock_dequeue_err_skb(sk);
3767	if (skb == NULL)
3768		goto out;
3769
3770	copied = skb->len;
3771	if (copied > len) {
3772		msg->msg_flags |= MSG_TRUNC;
3773		copied = len;
3774	}
3775	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3776	if (err)
3777		goto out_free_skb;
3778
3779	sock_recv_timestamp(msg, sk, skb);
3780
3781	serr = SKB_EXT_ERR(skb);
3782	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3783
3784	msg->msg_flags |= MSG_ERRQUEUE;
3785	err = copied;
3786
3787out_free_skb:
3788	kfree_skb(skb);
3789out:
3790	return err;
3791}
3792EXPORT_SYMBOL(sock_recv_errqueue);
3793
3794/*
3795 *	Get a socket option on an socket.
3796 *
3797 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3798 *	asynchronous errors should be reported by getsockopt. We assume
3799 *	this means if you specify SO_ERROR (otherwise what is the point of it).
3800 */
3801int sock_common_getsockopt(struct socket *sock, int level, int optname,
3802			   char __user *optval, int __user *optlen)
3803{
3804	struct sock *sk = sock->sk;
3805
3806	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3807	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3808}
3809EXPORT_SYMBOL(sock_common_getsockopt);
3810
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3811int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3812			int flags)
3813{
3814	struct sock *sk = sock->sk;
3815	int addr_len = 0;
3816	int err;
3817
3818	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
 
3819	if (err >= 0)
3820		msg->msg_namelen = addr_len;
3821	return err;
3822}
3823EXPORT_SYMBOL(sock_common_recvmsg);
3824
3825/*
3826 *	Set socket options on an inet socket.
3827 */
3828int sock_common_setsockopt(struct socket *sock, int level, int optname,
3829			   sockptr_t optval, unsigned int optlen)
3830{
3831	struct sock *sk = sock->sk;
3832
3833	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3834	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3835}
3836EXPORT_SYMBOL(sock_common_setsockopt);
3837
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3838void sk_common_release(struct sock *sk)
3839{
3840	if (sk->sk_prot->destroy)
3841		sk->sk_prot->destroy(sk);
3842
3843	/*
3844	 * Observation: when sk_common_release is called, processes have
3845	 * no access to socket. But net still has.
3846	 * Step one, detach it from networking:
3847	 *
3848	 * A. Remove from hash tables.
3849	 */
3850
3851	sk->sk_prot->unhash(sk);
3852
3853	/*
3854	 * In this point socket cannot receive new packets, but it is possible
3855	 * that some packets are in flight because some CPU runs receiver and
3856	 * did hash table lookup before we unhashed socket. They will achieve
3857	 * receive queue and will be purged by socket destructor.
3858	 *
3859	 * Also we still have packets pending on receive queue and probably,
3860	 * our own packets waiting in device queues. sock_destroy will drain
3861	 * receive queue, but transmitted packets will delay socket destruction
3862	 * until the last reference will be released.
3863	 */
3864
3865	sock_orphan(sk);
3866
3867	xfrm_sk_free_policy(sk);
3868
 
 
3869	sock_put(sk);
3870}
3871EXPORT_SYMBOL(sk_common_release);
3872
3873void sk_get_meminfo(const struct sock *sk, u32 *mem)
3874{
3875	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3876
3877	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3878	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3879	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3880	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3881	mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk);
3882	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3883	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3884	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3885	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3886}
3887
3888#ifdef CONFIG_PROC_FS
 
 
 
 
 
3889static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3890
 
 
 
 
 
 
3891int sock_prot_inuse_get(struct net *net, struct proto *prot)
3892{
3893	int cpu, idx = prot->inuse_idx;
3894	int res = 0;
3895
3896	for_each_possible_cpu(cpu)
3897		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3898
3899	return res >= 0 ? res : 0;
3900}
3901EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3902
 
 
 
 
 
3903int sock_inuse_get(struct net *net)
3904{
3905	int cpu, res = 0;
3906
3907	for_each_possible_cpu(cpu)
3908		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3909
3910	return res;
3911}
3912
3913EXPORT_SYMBOL_GPL(sock_inuse_get);
3914
3915static int __net_init sock_inuse_init_net(struct net *net)
3916{
3917	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3918	if (net->core.prot_inuse == NULL)
3919		return -ENOMEM;
 
 
 
 
 
3920	return 0;
 
 
 
 
3921}
3922
3923static void __net_exit sock_inuse_exit_net(struct net *net)
3924{
3925	free_percpu(net->core.prot_inuse);
 
3926}
3927
3928static struct pernet_operations net_inuse_ops = {
3929	.init = sock_inuse_init_net,
3930	.exit = sock_inuse_exit_net,
3931};
3932
3933static __init int net_inuse_init(void)
3934{
3935	if (register_pernet_subsys(&net_inuse_ops))
3936		panic("Cannot initialize net inuse counters");
3937
3938	return 0;
3939}
3940
3941core_initcall(net_inuse_init);
3942
3943static int assign_proto_idx(struct proto *prot)
3944{
3945	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3946
3947	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3948		pr_err("PROTO_INUSE_NR exhausted\n");
3949		return -ENOSPC;
3950	}
3951
3952	set_bit(prot->inuse_idx, proto_inuse_idx);
3953	return 0;
3954}
3955
3956static void release_proto_idx(struct proto *prot)
3957{
3958	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3959		clear_bit(prot->inuse_idx, proto_inuse_idx);
3960}
3961#else
3962static inline int assign_proto_idx(struct proto *prot)
3963{
3964	return 0;
3965}
3966
3967static inline void release_proto_idx(struct proto *prot)
3968{
3969}
3970
3971#endif
3972
3973static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3974{
3975	if (!twsk_prot)
3976		return;
3977	kfree(twsk_prot->twsk_slab_name);
3978	twsk_prot->twsk_slab_name = NULL;
3979	kmem_cache_destroy(twsk_prot->twsk_slab);
3980	twsk_prot->twsk_slab = NULL;
3981}
3982
3983static int tw_prot_init(const struct proto *prot)
3984{
3985	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3986
3987	if (!twsk_prot)
3988		return 0;
3989
3990	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3991					      prot->name);
3992	if (!twsk_prot->twsk_slab_name)
3993		return -ENOMEM;
3994
3995	twsk_prot->twsk_slab =
3996		kmem_cache_create(twsk_prot->twsk_slab_name,
3997				  twsk_prot->twsk_obj_size, 0,
3998				  SLAB_ACCOUNT | prot->slab_flags,
3999				  NULL);
4000	if (!twsk_prot->twsk_slab) {
4001		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4002			prot->name);
4003		return -ENOMEM;
4004	}
4005
4006	return 0;
4007}
 
4008
4009static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4010{
4011	if (!rsk_prot)
4012		return;
4013	kfree(rsk_prot->slab_name);
4014	rsk_prot->slab_name = NULL;
4015	kmem_cache_destroy(rsk_prot->slab);
4016	rsk_prot->slab = NULL;
4017}
4018
4019static int req_prot_init(const struct proto *prot)
4020{
4021	struct request_sock_ops *rsk_prot = prot->rsk_prot;
4022
4023	if (!rsk_prot)
4024		return 0;
4025
4026	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4027					prot->name);
4028	if (!rsk_prot->slab_name)
4029		return -ENOMEM;
4030
4031	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4032					   rsk_prot->obj_size, 0,
4033					   SLAB_ACCOUNT | prot->slab_flags,
4034					   NULL);
4035
4036	if (!rsk_prot->slab) {
4037		pr_crit("%s: Can't create request sock SLAB cache!\n",
4038			prot->name);
4039		return -ENOMEM;
4040	}
4041	return 0;
4042}
4043
4044int proto_register(struct proto *prot, int alloc_slab)
4045{
4046	int ret = -ENOBUFS;
4047
4048	if (prot->memory_allocated && !prot->sysctl_mem) {
4049		pr_err("%s: missing sysctl_mem\n", prot->name);
4050		return -EINVAL;
4051	}
4052	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4053		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4054		return -EINVAL;
4055	}
4056	if (alloc_slab) {
4057		prot->slab = kmem_cache_create_usercopy(prot->name,
4058					prot->obj_size, 0,
4059					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4060					prot->slab_flags,
4061					prot->useroffset, prot->usersize,
4062					NULL);
4063
4064		if (prot->slab == NULL) {
4065			pr_crit("%s: Can't create sock SLAB cache!\n",
4066				prot->name);
4067			goto out;
4068		}
4069
4070		if (req_prot_init(prot))
4071			goto out_free_request_sock_slab;
4072
4073		if (tw_prot_init(prot))
4074			goto out_free_timewait_sock_slab;
 
 
 
 
 
 
 
 
 
 
 
 
 
4075	}
4076
4077	mutex_lock(&proto_list_mutex);
4078	ret = assign_proto_idx(prot);
4079	if (ret) {
4080		mutex_unlock(&proto_list_mutex);
4081		goto out_free_timewait_sock_slab;
4082	}
4083	list_add(&prot->node, &proto_list);
 
4084	mutex_unlock(&proto_list_mutex);
4085	return ret;
4086
4087out_free_timewait_sock_slab:
4088	if (alloc_slab)
4089		tw_prot_cleanup(prot->twsk_prot);
4090out_free_request_sock_slab:
4091	if (alloc_slab) {
4092		req_prot_cleanup(prot->rsk_prot);
4093
4094		kmem_cache_destroy(prot->slab);
4095		prot->slab = NULL;
4096	}
4097out:
4098	return ret;
4099}
4100EXPORT_SYMBOL(proto_register);
4101
4102void proto_unregister(struct proto *prot)
4103{
4104	mutex_lock(&proto_list_mutex);
4105	release_proto_idx(prot);
4106	list_del(&prot->node);
4107	mutex_unlock(&proto_list_mutex);
4108
4109	kmem_cache_destroy(prot->slab);
4110	prot->slab = NULL;
4111
4112	req_prot_cleanup(prot->rsk_prot);
4113	tw_prot_cleanup(prot->twsk_prot);
 
 
 
 
 
4114}
4115EXPORT_SYMBOL(proto_unregister);
4116
4117int sock_load_diag_module(int family, int protocol)
4118{
4119	if (!protocol) {
4120		if (!sock_is_registered(family))
4121			return -ENOENT;
4122
4123		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4124				      NETLINK_SOCK_DIAG, family);
4125	}
4126
4127#ifdef CONFIG_INET
4128	if (family == AF_INET &&
4129	    protocol != IPPROTO_RAW &&
4130	    protocol < MAX_INET_PROTOS &&
4131	    !rcu_access_pointer(inet_protos[protocol]))
4132		return -ENOENT;
4133#endif
4134
4135	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4136			      NETLINK_SOCK_DIAG, family, protocol);
4137}
4138EXPORT_SYMBOL(sock_load_diag_module);
4139
4140#ifdef CONFIG_PROC_FS
4141static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4142	__acquires(proto_list_mutex)
4143{
4144	mutex_lock(&proto_list_mutex);
4145	return seq_list_start_head(&proto_list, *pos);
4146}
4147
4148static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4149{
4150	return seq_list_next(v, &proto_list, pos);
4151}
4152
4153static void proto_seq_stop(struct seq_file *seq, void *v)
4154	__releases(proto_list_mutex)
4155{
4156	mutex_unlock(&proto_list_mutex);
4157}
4158
4159static char proto_method_implemented(const void *method)
4160{
4161	return method == NULL ? 'n' : 'y';
4162}
4163static long sock_prot_memory_allocated(struct proto *proto)
4164{
4165	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4166}
4167
4168static const char *sock_prot_memory_pressure(struct proto *proto)
4169{
4170	return proto->memory_pressure != NULL ?
4171	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4172}
4173
4174static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4175{
4176
4177	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4178			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4179		   proto->name,
4180		   proto->obj_size,
4181		   sock_prot_inuse_get(seq_file_net(seq), proto),
4182		   sock_prot_memory_allocated(proto),
4183		   sock_prot_memory_pressure(proto),
4184		   proto->max_header,
4185		   proto->slab == NULL ? "no" : "yes",
4186		   module_name(proto->owner),
4187		   proto_method_implemented(proto->close),
4188		   proto_method_implemented(proto->connect),
4189		   proto_method_implemented(proto->disconnect),
4190		   proto_method_implemented(proto->accept),
4191		   proto_method_implemented(proto->ioctl),
4192		   proto_method_implemented(proto->init),
4193		   proto_method_implemented(proto->destroy),
4194		   proto_method_implemented(proto->shutdown),
4195		   proto_method_implemented(proto->setsockopt),
4196		   proto_method_implemented(proto->getsockopt),
4197		   proto_method_implemented(proto->sendmsg),
4198		   proto_method_implemented(proto->recvmsg),
 
4199		   proto_method_implemented(proto->bind),
4200		   proto_method_implemented(proto->backlog_rcv),
4201		   proto_method_implemented(proto->hash),
4202		   proto_method_implemented(proto->unhash),
4203		   proto_method_implemented(proto->get_port),
4204		   proto_method_implemented(proto->enter_memory_pressure));
4205}
4206
4207static int proto_seq_show(struct seq_file *seq, void *v)
4208{
4209	if (v == &proto_list)
4210		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4211			   "protocol",
4212			   "size",
4213			   "sockets",
4214			   "memory",
4215			   "press",
4216			   "maxhdr",
4217			   "slab",
4218			   "module",
4219			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4220	else
4221		proto_seq_printf(seq, list_entry(v, struct proto, node));
4222	return 0;
4223}
4224
4225static const struct seq_operations proto_seq_ops = {
4226	.start  = proto_seq_start,
4227	.next   = proto_seq_next,
4228	.stop   = proto_seq_stop,
4229	.show   = proto_seq_show,
4230};
4231
 
 
 
 
 
 
 
 
 
 
 
 
 
4232static __net_init int proto_init_net(struct net *net)
4233{
4234	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4235			sizeof(struct seq_net_private)))
4236		return -ENOMEM;
4237
4238	return 0;
4239}
4240
4241static __net_exit void proto_exit_net(struct net *net)
4242{
4243	remove_proc_entry("protocols", net->proc_net);
4244}
4245
4246
4247static __net_initdata struct pernet_operations proto_net_ops = {
4248	.init = proto_init_net,
4249	.exit = proto_exit_net,
4250};
4251
4252static int __init proto_init(void)
4253{
4254	return register_pernet_subsys(&proto_net_ops);
4255}
4256
4257subsys_initcall(proto_init);
4258
4259#endif /* PROC_FS */
4260
4261#ifdef CONFIG_NET_RX_BUSY_POLL
4262bool sk_busy_loop_end(void *p, unsigned long start_time)
4263{
4264	struct sock *sk = p;
4265
4266	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4267		return true;
4268
4269	if (sk_is_udp(sk) &&
4270	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4271		return true;
4272
4273	return sk_busy_loop_timeout(sk, start_time);
4274}
4275EXPORT_SYMBOL(sk_busy_loop_end);
4276#endif /* CONFIG_NET_RX_BUSY_POLL */
4277
4278int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4279{
4280	if (!sk->sk_prot->bind_add)
4281		return -EOPNOTSUPP;
4282	return sk->sk_prot->bind_add(sk, addr, addr_len);
4283}
4284EXPORT_SYMBOL(sock_bind_add);
4285
4286/* Copy 'size' bytes from userspace and return `size` back to userspace */
4287int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4288		     void __user *arg, void *karg, size_t size)
4289{
4290	int ret;
4291
4292	if (copy_from_user(karg, arg, size))
4293		return -EFAULT;
4294
4295	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4296	if (ret)
4297		return ret;
4298
4299	if (copy_to_user(arg, karg, size))
4300		return -EFAULT;
4301
4302	return 0;
4303}
4304EXPORT_SYMBOL(sock_ioctl_inout);
4305
4306/* This is the most common ioctl prep function, where the result (4 bytes) is
4307 * copied back to userspace if the ioctl() returns successfully. No input is
4308 * copied from userspace as input argument.
4309 */
4310static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4311{
4312	int ret, karg = 0;
4313
4314	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4315	if (ret)
4316		return ret;
4317
4318	return put_user(karg, (int __user *)arg);
4319}
4320
4321/* A wrapper around sock ioctls, which copies the data from userspace
4322 * (depending on the protocol/ioctl), and copies back the result to userspace.
4323 * The main motivation for this function is to pass kernel memory to the
4324 * protocol ioctl callbacks, instead of userspace memory.
4325 */
4326int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4327{
4328	int rc = 1;
4329
4330	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4331		rc = ipmr_sk_ioctl(sk, cmd, arg);
4332	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4333		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4334	else if (sk_is_phonet(sk))
4335		rc = phonet_sk_ioctl(sk, cmd, arg);
4336
4337	/* If ioctl was processed, returns its value */
4338	if (rc <= 0)
4339		return rc;
4340
4341	/* Otherwise call the default handler */
4342	return sock_ioctl_out(sk, cmd, arg);
4343}
4344EXPORT_SYMBOL(sk_ioctl);
4345
4346static int __init sock_struct_check(void)
4347{
4348	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4349	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4350	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4351	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4352	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4353
4354	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4355	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4356	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4357	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4358	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4359	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4360	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4361	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4362	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4363
4364	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4365	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4366	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4367
4368	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4369	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4370	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4371	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4372
4373	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4374	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4375	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_sndbuf);
4376	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4377	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4378	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4379	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4380	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4381	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4382	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm);
4383	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status);
4384	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4385	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4386	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4387	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4388	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4389
4390	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4391	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4392	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4393	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4394	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4395	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4396	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4397	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4398	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4399	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4400	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4401	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4402	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4403	return 0;
4404}
4405
4406core_initcall(sock_struct_check);
v4.17
 
   1/*
   2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   3 *		operating system.  INET is implemented using the  BSD Socket
   4 *		interface as the means of communication with the user level.
   5 *
   6 *		Generic socket support routines. Memory allocators, socket lock/release
   7 *		handler for protocols to use and generic option handler.
   8 *
   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 *		This program is free software; you can redistribute it and/or
  87 *		modify it under the terms of the GNU General Public License
  88 *		as published by the Free Software Foundation; either version
  89 *		2 of the License, or (at your option) any later version.
  90 */
  91
  92#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  93
 
  94#include <linux/capability.h>
  95#include <linux/errno.h>
  96#include <linux/errqueue.h>
  97#include <linux/types.h>
  98#include <linux/socket.h>
  99#include <linux/in.h>
 100#include <linux/kernel.h>
 101#include <linux/module.h>
 102#include <linux/proc_fs.h>
 103#include <linux/seq_file.h>
 104#include <linux/sched.h>
 105#include <linux/sched/mm.h>
 106#include <linux/timer.h>
 107#include <linux/string.h>
 108#include <linux/sockios.h>
 109#include <linux/net.h>
 110#include <linux/mm.h>
 111#include <linux/slab.h>
 112#include <linux/interrupt.h>
 113#include <linux/poll.h>
 114#include <linux/tcp.h>
 
 115#include <linux/init.h>
 116#include <linux/highmem.h>
 117#include <linux/user_namespace.h>
 118#include <linux/static_key.h>
 119#include <linux/memcontrol.h>
 120#include <linux/prefetch.h>
 
 
 
 
 121
 122#include <linux/uaccess.h>
 123
 124#include <linux/netdevice.h>
 125#include <net/protocol.h>
 126#include <linux/skbuff.h>
 
 127#include <net/net_namespace.h>
 128#include <net/request_sock.h>
 129#include <net/sock.h>
 
 130#include <linux/net_tstamp.h>
 131#include <net/xfrm.h>
 132#include <linux/ipsec.h>
 133#include <net/cls_cgroup.h>
 134#include <net/netprio_cgroup.h>
 135#include <linux/sock_diag.h>
 136
 137#include <linux/filter.h>
 138#include <net/sock_reuseport.h>
 
 139
 140#include <trace/events/sock.h>
 141
 142#include <net/tcp.h>
 143#include <net/busy_poll.h>
 
 
 
 
 
 144
 145static DEFINE_MUTEX(proto_list_mutex);
 146static LIST_HEAD(proto_list);
 147
 148static void sock_inuse_add(struct net *net, int val);
 
 149
 150/**
 151 * sk_ns_capable - General socket capability test
 152 * @sk: Socket to use a capability on or through
 153 * @user_ns: The user namespace of the capability to use
 154 * @cap: The capability to use
 155 *
 156 * Test to see if the opener of the socket had when the socket was
 157 * created and the current process has the capability @cap in the user
 158 * namespace @user_ns.
 159 */
 160bool sk_ns_capable(const struct sock *sk,
 161		   struct user_namespace *user_ns, int cap)
 162{
 163	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
 164		ns_capable(user_ns, cap);
 165}
 166EXPORT_SYMBOL(sk_ns_capable);
 167
 168/**
 169 * sk_capable - Socket global capability test
 170 * @sk: Socket to use a capability on or through
 171 * @cap: The global capability to use
 172 *
 173 * Test to see if the opener of the socket had when the socket was
 174 * created and the current process has the capability @cap in all user
 175 * namespaces.
 176 */
 177bool sk_capable(const struct sock *sk, int cap)
 178{
 179	return sk_ns_capable(sk, &init_user_ns, cap);
 180}
 181EXPORT_SYMBOL(sk_capable);
 182
 183/**
 184 * sk_net_capable - Network namespace socket capability test
 185 * @sk: Socket to use a capability on or through
 186 * @cap: The capability to use
 187 *
 188 * Test to see if the opener of the socket had when the socket was created
 189 * and the current process has the capability @cap over the network namespace
 190 * the socket is a member of.
 191 */
 192bool sk_net_capable(const struct sock *sk, int cap)
 193{
 194	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
 195}
 196EXPORT_SYMBOL(sk_net_capable);
 197
 198/*
 199 * Each address family might have different locking rules, so we have
 200 * one slock key per address family and separate keys for internal and
 201 * userspace sockets.
 202 */
 203static struct lock_class_key af_family_keys[AF_MAX];
 204static struct lock_class_key af_family_kern_keys[AF_MAX];
 205static struct lock_class_key af_family_slock_keys[AF_MAX];
 206static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
 207
 208/*
 209 * Make lock validator output more readable. (we pre-construct these
 210 * strings build-time, so that runtime initialization of socket
 211 * locks is fast):
 212 */
 213
 214#define _sock_locks(x)						  \
 215  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
 216  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
 217  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
 218  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
 219  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
 220  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
 221  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
 222  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
 223  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
 224  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
 225  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
 226  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
 227  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
 228  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
 229  x "AF_QIPCRTR",	x "AF_SMC"	,	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  "rlock-AF_UNSPEC", "rlock-AF_UNIX"     , "rlock-AF_INET"     ,
 252  "rlock-AF_AX25"  , "rlock-AF_IPX"      , "rlock-AF_APPLETALK",
 253  "rlock-AF_NETROM", "rlock-AF_BRIDGE"   , "rlock-AF_ATMPVC"   ,
 254  "rlock-AF_X25"   , "rlock-AF_INET6"    , "rlock-AF_ROSE"     ,
 255  "rlock-AF_DECnet", "rlock-AF_NETBEUI"  , "rlock-AF_SECURITY" ,
 256  "rlock-AF_KEY"   , "rlock-AF_NETLINK"  , "rlock-AF_PACKET"   ,
 257  "rlock-AF_ASH"   , "rlock-AF_ECONET"   , "rlock-AF_ATMSVC"   ,
 258  "rlock-AF_RDS"   , "rlock-AF_SNA"      , "rlock-AF_IRDA"     ,
 259  "rlock-AF_PPPOX" , "rlock-AF_WANPIPE"  , "rlock-AF_LLC"      ,
 260  "rlock-27"       , "rlock-28"          , "rlock-AF_CAN"      ,
 261  "rlock-AF_TIPC"  , "rlock-AF_BLUETOOTH", "rlock-AF_IUCV"     ,
 262  "rlock-AF_RXRPC" , "rlock-AF_ISDN"     , "rlock-AF_PHONET"   ,
 263  "rlock-AF_IEEE802154", "rlock-AF_CAIF" , "rlock-AF_ALG"      ,
 264  "rlock-AF_NFC"   , "rlock-AF_VSOCK"    , "rlock-AF_KCM"      ,
 265  "rlock-AF_QIPCRTR", "rlock-AF_SMC"     , "rlock-AF_MAX"
 266};
 267static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
 268  "wlock-AF_UNSPEC", "wlock-AF_UNIX"     , "wlock-AF_INET"     ,
 269  "wlock-AF_AX25"  , "wlock-AF_IPX"      , "wlock-AF_APPLETALK",
 270  "wlock-AF_NETROM", "wlock-AF_BRIDGE"   , "wlock-AF_ATMPVC"   ,
 271  "wlock-AF_X25"   , "wlock-AF_INET6"    , "wlock-AF_ROSE"     ,
 272  "wlock-AF_DECnet", "wlock-AF_NETBEUI"  , "wlock-AF_SECURITY" ,
 273  "wlock-AF_KEY"   , "wlock-AF_NETLINK"  , "wlock-AF_PACKET"   ,
 274  "wlock-AF_ASH"   , "wlock-AF_ECONET"   , "wlock-AF_ATMSVC"   ,
 275  "wlock-AF_RDS"   , "wlock-AF_SNA"      , "wlock-AF_IRDA"     ,
 276  "wlock-AF_PPPOX" , "wlock-AF_WANPIPE"  , "wlock-AF_LLC"      ,
 277  "wlock-27"       , "wlock-28"          , "wlock-AF_CAN"      ,
 278  "wlock-AF_TIPC"  , "wlock-AF_BLUETOOTH", "wlock-AF_IUCV"     ,
 279  "wlock-AF_RXRPC" , "wlock-AF_ISDN"     , "wlock-AF_PHONET"   ,
 280  "wlock-AF_IEEE802154", "wlock-AF_CAIF" , "wlock-AF_ALG"      ,
 281  "wlock-AF_NFC"   , "wlock-AF_VSOCK"    , "wlock-AF_KCM"      ,
 282  "wlock-AF_QIPCRTR", "wlock-AF_SMC"     , "wlock-AF_MAX"
 283};
 284static const char *const af_family_elock_key_strings[AF_MAX+1] = {
 285  "elock-AF_UNSPEC", "elock-AF_UNIX"     , "elock-AF_INET"     ,
 286  "elock-AF_AX25"  , "elock-AF_IPX"      , "elock-AF_APPLETALK",
 287  "elock-AF_NETROM", "elock-AF_BRIDGE"   , "elock-AF_ATMPVC"   ,
 288  "elock-AF_X25"   , "elock-AF_INET6"    , "elock-AF_ROSE"     ,
 289  "elock-AF_DECnet", "elock-AF_NETBEUI"  , "elock-AF_SECURITY" ,
 290  "elock-AF_KEY"   , "elock-AF_NETLINK"  , "elock-AF_PACKET"   ,
 291  "elock-AF_ASH"   , "elock-AF_ECONET"   , "elock-AF_ATMSVC"   ,
 292  "elock-AF_RDS"   , "elock-AF_SNA"      , "elock-AF_IRDA"     ,
 293  "elock-AF_PPPOX" , "elock-AF_WANPIPE"  , "elock-AF_LLC"      ,
 294  "elock-27"       , "elock-28"          , "elock-AF_CAN"      ,
 295  "elock-AF_TIPC"  , "elock-AF_BLUETOOTH", "elock-AF_IUCV"     ,
 296  "elock-AF_RXRPC" , "elock-AF_ISDN"     , "elock-AF_PHONET"   ,
 297  "elock-AF_IEEE802154", "elock-AF_CAIF" , "elock-AF_ALG"      ,
 298  "elock-AF_NFC"   , "elock-AF_VSOCK"    , "elock-AF_KCM"      ,
 299  "elock-AF_QIPCRTR", "elock-AF_SMC"     , "elock-AF_MAX"
 300};
 301
 302/*
 303 * sk_callback_lock and sk queues locking rules are per-address-family,
 304 * so split the lock classes by using a per-AF key:
 305 */
 306static struct lock_class_key af_callback_keys[AF_MAX];
 307static struct lock_class_key af_rlock_keys[AF_MAX];
 308static struct lock_class_key af_wlock_keys[AF_MAX];
 309static struct lock_class_key af_elock_keys[AF_MAX];
 310static struct lock_class_key af_kern_callback_keys[AF_MAX];
 311
 312/* Run time adjustable parameters. */
 313__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 314EXPORT_SYMBOL(sysctl_wmem_max);
 315__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 316EXPORT_SYMBOL(sysctl_rmem_max);
 317__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 318__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 319
 320/* Maximal space eaten by iovec or ancillary data plus some space */
 321int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
 322EXPORT_SYMBOL(sysctl_optmem_max);
 323
 324int sysctl_tstamp_allow_data __read_mostly = 1;
 325
 326struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
 327EXPORT_SYMBOL_GPL(memalloc_socks);
 328
 329/**
 330 * sk_set_memalloc - sets %SOCK_MEMALLOC
 331 * @sk: socket to set it on
 332 *
 333 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 334 * It's the responsibility of the admin to adjust min_free_kbytes
 335 * to meet the requirements
 336 */
 337void sk_set_memalloc(struct sock *sk)
 338{
 339	sock_set_flag(sk, SOCK_MEMALLOC);
 340	sk->sk_allocation |= __GFP_MEMALLOC;
 341	static_key_slow_inc(&memalloc_socks);
 342}
 343EXPORT_SYMBOL_GPL(sk_set_memalloc);
 344
 345void sk_clear_memalloc(struct sock *sk)
 346{
 347	sock_reset_flag(sk, SOCK_MEMALLOC);
 348	sk->sk_allocation &= ~__GFP_MEMALLOC;
 349	static_key_slow_dec(&memalloc_socks);
 350
 351	/*
 352	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 353	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 354	 * it has rmem allocations due to the last swapfile being deactivated
 355	 * but there is a risk that the socket is unusable due to exceeding
 356	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 357	 */
 358	sk_mem_reclaim(sk);
 359}
 360EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 361
 362int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 363{
 364	int ret;
 365	unsigned int noreclaim_flag;
 366
 367	/* these should have been dropped before queueing */
 368	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 369
 370	noreclaim_flag = memalloc_noreclaim_save();
 371	ret = sk->sk_backlog_rcv(sk, skb);
 
 
 
 372	memalloc_noreclaim_restore(noreclaim_flag);
 373
 374	return ret;
 375}
 376EXPORT_SYMBOL(__sk_backlog_rcv);
 377
 378static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 379{
 380	struct timeval tv;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 381
 382	if (optlen < sizeof(tv))
 383		return -EINVAL;
 384	if (copy_from_user(&tv, optval, sizeof(tv)))
 385		return -EFAULT;
 386	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 387		return -EDOM;
 388
 389	if (tv.tv_sec < 0) {
 390		static int warned __read_mostly;
 391
 392		*timeo_p = 0;
 393		if (warned < 10 && net_ratelimit()) {
 394			warned++;
 395			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 396				__func__, current->comm, task_pid_nr(current));
 397		}
 398		return 0;
 399	}
 400	*timeo_p = MAX_SCHEDULE_TIMEOUT;
 401	if (tv.tv_sec == 0 && tv.tv_usec == 0)
 402		return 0;
 403	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
 404		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ);
 
 405	return 0;
 406}
 407
 408static void sock_warn_obsolete_bsdism(const char *name)
 409{
 410	static int warned;
 411	static char warncomm[TASK_COMM_LEN];
 412	if (strcmp(warncomm, current->comm) && warned < 5) {
 413		strcpy(warncomm,  current->comm);
 414		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
 415			warncomm, name);
 416		warned++;
 417	}
 418}
 419
 420static bool sock_needs_netstamp(const struct sock *sk)
 421{
 422	switch (sk->sk_family) {
 423	case AF_UNSPEC:
 424	case AF_UNIX:
 425		return false;
 426	default:
 427		return true;
 428	}
 429}
 430
 431static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 432{
 433	if (sk->sk_flags & flags) {
 434		sk->sk_flags &= ~flags;
 435		if (sock_needs_netstamp(sk) &&
 436		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 437			net_disable_timestamp();
 438	}
 439}
 440
 441
 442int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 443{
 444	unsigned long flags;
 445	struct sk_buff_head *list = &sk->sk_receive_queue;
 446
 447	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
 448		atomic_inc(&sk->sk_drops);
 449		trace_sock_rcvqueue_full(sk, skb);
 450		return -ENOMEM;
 451	}
 452
 453	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 454		atomic_inc(&sk->sk_drops);
 455		return -ENOBUFS;
 456	}
 457
 458	skb->dev = NULL;
 459	skb_set_owner_r(skb, sk);
 460
 461	/* we escape from rcu protected region, make sure we dont leak
 462	 * a norefcounted dst
 463	 */
 464	skb_dst_force(skb);
 465
 466	spin_lock_irqsave(&list->lock, flags);
 467	sock_skb_set_dropcount(sk, skb);
 468	__skb_queue_tail(list, skb);
 469	spin_unlock_irqrestore(&list->lock, flags);
 470
 471	if (!sock_flag(sk, SOCK_DEAD))
 472		sk->sk_data_ready(sk);
 473	return 0;
 474}
 475EXPORT_SYMBOL(__sock_queue_rcv_skb);
 476
 477int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 478{
 
 479	int err;
 480
 481	err = sk_filter(sk, skb);
 482	if (err)
 483		return err;
 484
 485	return __sock_queue_rcv_skb(sk, skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 486}
 487EXPORT_SYMBOL(sock_queue_rcv_skb);
 488
 489int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
 490		     const int nested, unsigned int trim_cap, bool refcounted)
 491{
 492	int rc = NET_RX_SUCCESS;
 493
 494	if (sk_filter_trim_cap(sk, skb, trim_cap))
 495		goto discard_and_relse;
 496
 497	skb->dev = NULL;
 498
 499	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 500		atomic_inc(&sk->sk_drops);
 501		goto discard_and_relse;
 502	}
 503	if (nested)
 504		bh_lock_sock_nested(sk);
 505	else
 506		bh_lock_sock(sk);
 507	if (!sock_owned_by_user(sk)) {
 508		/*
 509		 * trylock + unlock semantics:
 510		 */
 511		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 512
 513		rc = sk_backlog_rcv(sk, skb);
 514
 515		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
 516	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 517		bh_unlock_sock(sk);
 518		atomic_inc(&sk->sk_drops);
 519		goto discard_and_relse;
 520	}
 521
 522	bh_unlock_sock(sk);
 523out:
 524	if (refcounted)
 525		sock_put(sk);
 526	return rc;
 527discard_and_relse:
 528	kfree_skb(skb);
 529	goto out;
 530}
 531EXPORT_SYMBOL(__sk_receive_skb);
 532
 
 
 
 
 533struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 534{
 535	struct dst_entry *dst = __sk_dst_get(sk);
 536
 537	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 
 
 538		sk_tx_queue_clear(sk);
 539		sk->sk_dst_pending_confirm = 0;
 540		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 541		dst_release(dst);
 542		return NULL;
 543	}
 544
 545	return dst;
 546}
 547EXPORT_SYMBOL(__sk_dst_check);
 548
 549struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 550{
 551	struct dst_entry *dst = sk_dst_get(sk);
 552
 553	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 
 
 554		sk_dst_reset(sk);
 555		dst_release(dst);
 556		return NULL;
 557	}
 558
 559	return dst;
 560}
 561EXPORT_SYMBOL(sk_dst_check);
 562
 563static int sock_setbindtodevice(struct sock *sk, char __user *optval,
 564				int optlen)
 565{
 566	int ret = -ENOPROTOOPT;
 567#ifdef CONFIG_NETDEVICES
 568	struct net *net = sock_net(sk);
 569	char devname[IFNAMSIZ];
 570	int index;
 571
 572	/* Sorry... */
 573	ret = -EPERM;
 574	if (!ns_capable(net->user_ns, CAP_NET_RAW))
 575		goto out;
 576
 577	ret = -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 578	if (optlen < 0)
 579		goto out;
 580
 581	/* Bind this socket to a particular device like "eth0",
 582	 * as specified in the passed interface name. If the
 583	 * name is "" or the option length is zero the socket
 584	 * is not bound.
 585	 */
 586	if (optlen > IFNAMSIZ - 1)
 587		optlen = IFNAMSIZ - 1;
 588	memset(devname, 0, sizeof(devname));
 589
 590	ret = -EFAULT;
 591	if (copy_from_user(devname, optval, optlen))
 592		goto out;
 593
 594	index = 0;
 595	if (devname[0] != '\0') {
 596		struct net_device *dev;
 597
 598		rcu_read_lock();
 599		dev = dev_get_by_name_rcu(net, devname);
 600		if (dev)
 601			index = dev->ifindex;
 602		rcu_read_unlock();
 603		ret = -ENODEV;
 604		if (!dev)
 605			goto out;
 606	}
 607
 608	lock_sock(sk);
 609	sk->sk_bound_dev_if = index;
 610	sk_dst_reset(sk);
 611	release_sock(sk);
 612
 613	ret = 0;
 614
 615out:
 616#endif
 617
 618	return ret;
 619}
 620
 621static int sock_getbindtodevice(struct sock *sk, char __user *optval,
 622				int __user *optlen, int len)
 623{
 624	int ret = -ENOPROTOOPT;
 625#ifdef CONFIG_NETDEVICES
 
 626	struct net *net = sock_net(sk);
 627	char devname[IFNAMSIZ];
 628
 629	if (sk->sk_bound_dev_if == 0) {
 630		len = 0;
 631		goto zero;
 632	}
 633
 634	ret = -EINVAL;
 635	if (len < IFNAMSIZ)
 636		goto out;
 637
 638	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
 639	if (ret)
 640		goto out;
 641
 642	len = strlen(devname) + 1;
 643
 644	ret = -EFAULT;
 645	if (copy_to_user(optval, devname, len))
 646		goto out;
 647
 648zero:
 649	ret = -EFAULT;
 650	if (put_user(len, optlen))
 651		goto out;
 652
 653	ret = 0;
 654
 655out:
 656#endif
 657
 658	return ret;
 659}
 660
 661static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
 662{
 663	if (valbool)
 664		sock_set_flag(sk, bit);
 665	else
 666		sock_reset_flag(sk, bit);
 667}
 668
 669bool sk_mc_loop(struct sock *sk)
 670{
 671	if (dev_recursion_level())
 672		return false;
 673	if (!sk)
 674		return true;
 675	switch (sk->sk_family) {
 
 676	case AF_INET:
 677		return inet_sk(sk)->mc_loop;
 678#if IS_ENABLED(CONFIG_IPV6)
 679	case AF_INET6:
 680		return inet6_sk(sk)->mc_loop;
 681#endif
 682	}
 683	WARN_ON(1);
 684	return true;
 685}
 686EXPORT_SYMBOL(sk_mc_loop);
 687
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 688/*
 689 *	This is meant for all protocols to use and covers goings on
 690 *	at the socket level. Everything here is generic.
 691 */
 692
 693int sock_setsockopt(struct socket *sock, int level, int optname,
 694		    char __user *optval, unsigned int optlen)
 695{
 696	struct sock *sk = sock->sk;
 
 
 697	int val;
 698	int valbool;
 699	struct linger ling;
 700	int ret = 0;
 701
 702	/*
 703	 *	Options without arguments
 704	 */
 705
 706	if (optname == SO_BINDTODEVICE)
 707		return sock_setbindtodevice(sk, optval, optlen);
 708
 709	if (optlen < sizeof(int))
 710		return -EINVAL;
 711
 712	if (get_user(val, (int __user *)optval))
 713		return -EFAULT;
 714
 715	valbool = val ? 1 : 0;
 716
 717	lock_sock(sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 718
 719	switch (optname) {
 720	case SO_DEBUG:
 721		if (val && !capable(CAP_NET_ADMIN))
 722			ret = -EACCES;
 723		else
 724			sock_valbool_flag(sk, SOCK_DBG, valbool);
 725		break;
 726	case SO_REUSEADDR:
 727		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
 728		break;
 729	case SO_REUSEPORT:
 730		sk->sk_reuseport = valbool;
 731		break;
 732	case SO_TYPE:
 733	case SO_PROTOCOL:
 734	case SO_DOMAIN:
 735	case SO_ERROR:
 736		ret = -ENOPROTOOPT;
 737		break;
 738	case SO_DONTROUTE:
 739		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
 
 740		break;
 741	case SO_BROADCAST:
 742		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
 743		break;
 744	case SO_SNDBUF:
 745		/* Don't error on this BSD doesn't and if you think
 746		 * about it this is right. Otherwise apps have to
 747		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
 748		 * are treated in BSD as hints
 749		 */
 750		val = min_t(u32, val, sysctl_wmem_max);
 751set_sndbuf:
 
 
 
 
 752		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
 753		sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
 
 754		/* Wake up sending tasks if we upped the value. */
 755		sk->sk_write_space(sk);
 756		break;
 757
 758	case SO_SNDBUFFORCE:
 759		if (!capable(CAP_NET_ADMIN)) {
 760			ret = -EPERM;
 761			break;
 762		}
 
 
 
 
 
 
 763		goto set_sndbuf;
 764
 765	case SO_RCVBUF:
 766		/* Don't error on this BSD doesn't and if you think
 767		 * about it this is right. Otherwise apps have to
 768		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
 769		 * are treated in BSD as hints
 770		 */
 771		val = min_t(u32, val, sysctl_rmem_max);
 772set_rcvbuf:
 773		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 774		/*
 775		 * We double it on the way in to account for
 776		 * "struct sk_buff" etc. overhead.   Applications
 777		 * assume that the SO_RCVBUF setting they make will
 778		 * allow that much actual data to be received on that
 779		 * socket.
 780		 *
 781		 * Applications are unaware that "struct sk_buff" and
 782		 * other overheads allocate from the receive buffer
 783		 * during socket buffer allocation.
 784		 *
 785		 * And after considering the possible alternatives,
 786		 * returning the value we actually used in getsockopt
 787		 * is the most desirable behavior.
 788		 */
 789		sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
 790		break;
 791
 792	case SO_RCVBUFFORCE:
 793		if (!capable(CAP_NET_ADMIN)) {
 794			ret = -EPERM;
 795			break;
 796		}
 797		goto set_rcvbuf;
 
 
 
 
 
 798
 799	case SO_KEEPALIVE:
 800		if (sk->sk_prot->keepalive)
 801			sk->sk_prot->keepalive(sk, valbool);
 802		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
 803		break;
 804
 805	case SO_OOBINLINE:
 806		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
 807		break;
 808
 809	case SO_NO_CHECK:
 810		sk->sk_no_check_tx = valbool;
 811		break;
 812
 813	case SO_PRIORITY:
 814		if ((val >= 0 && val <= 6) ||
 815		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 816			sk->sk_priority = val;
 817		else
 818			ret = -EPERM;
 819		break;
 820
 821	case SO_LINGER:
 822		if (optlen < sizeof(ling)) {
 823			ret = -EINVAL;	/* 1003.1g */
 824			break;
 825		}
 826		if (copy_from_user(&ling, optval, sizeof(ling))) {
 827			ret = -EFAULT;
 828			break;
 829		}
 830		if (!ling.l_onoff)
 831			sock_reset_flag(sk, SOCK_LINGER);
 832		else {
 833#if (BITS_PER_LONG == 32)
 834			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
 835				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
 
 836			else
 837#endif
 838				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
 839			sock_set_flag(sk, SOCK_LINGER);
 840		}
 841		break;
 842
 843	case SO_BSDCOMPAT:
 844		sock_warn_obsolete_bsdism("setsockopt");
 845		break;
 846
 847	case SO_PASSCRED:
 848		if (valbool)
 849			set_bit(SOCK_PASSCRED, &sock->flags);
 850		else
 851			clear_bit(SOCK_PASSCRED, &sock->flags);
 852		break;
 853
 854	case SO_TIMESTAMP:
 855	case SO_TIMESTAMPNS:
 856		if (valbool)  {
 857			if (optname == SO_TIMESTAMP)
 858				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 859			else
 860				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
 861			sock_set_flag(sk, SOCK_RCVTSTAMP);
 862			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 863		} else {
 864			sock_reset_flag(sk, SOCK_RCVTSTAMP);
 865			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 866		}
 
 867		break;
 868
 869	case SO_TIMESTAMPING:
 870		if (val & ~SOF_TIMESTAMPING_MASK) {
 871			ret = -EINVAL;
 872			break;
 873		}
 874
 875		if (val & SOF_TIMESTAMPING_OPT_ID &&
 876		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
 877			if (sk->sk_protocol == IPPROTO_TCP &&
 878			    sk->sk_type == SOCK_STREAM) {
 879				if ((1 << sk->sk_state) &
 880				    (TCPF_CLOSE | TCPF_LISTEN)) {
 881					ret = -EINVAL;
 882					break;
 883				}
 884				sk->sk_tskey = tcp_sk(sk)->snd_una;
 885			} else {
 886				sk->sk_tskey = 0;
 887			}
 888		}
 889
 890		if (val & SOF_TIMESTAMPING_OPT_STATS &&
 891		    !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
 892			ret = -EINVAL;
 893			break;
 894		}
 895
 896		sk->sk_tsflags = val;
 897		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
 898			sock_enable_timestamp(sk,
 899					      SOCK_TIMESTAMPING_RX_SOFTWARE);
 900		else
 901			sock_disable_timestamp(sk,
 902					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
 903		break;
 904
 905	case SO_RCVLOWAT:
 906		if (val < 0)
 907			val = INT_MAX;
 908		sk->sk_rcvlowat = val ? : 1;
 
 
 
 
 
 909		break;
 910
 911	case SO_RCVTIMEO:
 912		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
 
 
 913		break;
 914
 915	case SO_SNDTIMEO:
 916		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
 
 
 917		break;
 918
 919	case SO_ATTACH_FILTER:
 920		ret = -EINVAL;
 921		if (optlen == sizeof(struct sock_fprog)) {
 922			struct sock_fprog fprog;
 923
 924			ret = -EFAULT;
 925			if (copy_from_user(&fprog, optval, sizeof(fprog)))
 926				break;
 927
 
 
 928			ret = sk_attach_filter(&fprog, sk);
 929		}
 930		break;
 931
 932	case SO_ATTACH_BPF:
 933		ret = -EINVAL;
 934		if (optlen == sizeof(u32)) {
 935			u32 ufd;
 936
 937			ret = -EFAULT;
 938			if (copy_from_user(&ufd, optval, sizeof(ufd)))
 939				break;
 940
 941			ret = sk_attach_bpf(ufd, sk);
 942		}
 943		break;
 944
 945	case SO_ATTACH_REUSEPORT_CBPF:
 946		ret = -EINVAL;
 947		if (optlen == sizeof(struct sock_fprog)) {
 948			struct sock_fprog fprog;
 949
 950			ret = -EFAULT;
 951			if (copy_from_user(&fprog, optval, sizeof(fprog)))
 952				break;
 953
 
 
 954			ret = sk_reuseport_attach_filter(&fprog, sk);
 955		}
 956		break;
 957
 958	case SO_ATTACH_REUSEPORT_EBPF:
 959		ret = -EINVAL;
 960		if (optlen == sizeof(u32)) {
 961			u32 ufd;
 962
 963			ret = -EFAULT;
 964			if (copy_from_user(&ufd, optval, sizeof(ufd)))
 965				break;
 966
 967			ret = sk_reuseport_attach_bpf(ufd, sk);
 968		}
 969		break;
 970
 
 
 
 
 971	case SO_DETACH_FILTER:
 972		ret = sk_detach_filter(sk);
 973		break;
 974
 975	case SO_LOCK_FILTER:
 976		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
 977			ret = -EPERM;
 978		else
 979			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
 980		break;
 981
 982	case SO_PASSSEC:
 983		if (valbool)
 984			set_bit(SOCK_PASSSEC, &sock->flags);
 985		else
 986			clear_bit(SOCK_PASSSEC, &sock->flags);
 987		break;
 988	case SO_MARK:
 989		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 
 990			ret = -EPERM;
 991		else
 992			sk->sk_mark = val;
 
 
 
 
 
 993		break;
 994
 995	case SO_RXQ_OVFL:
 996		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
 997		break;
 998
 999	case SO_WIFI_STATUS:
1000		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1001		break;
1002
1003	case SO_PEEK_OFF:
1004		if (sock->ops->set_peek_off)
1005			ret = sock->ops->set_peek_off(sk, val);
1006		else
1007			ret = -EOPNOTSUPP;
1008		break;
1009
1010	case SO_NOFCS:
1011		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1012		break;
1013
1014	case SO_SELECT_ERR_QUEUE:
1015		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1016		break;
1017
1018#ifdef CONFIG_NET_RX_BUSY_POLL
1019	case SO_BUSY_POLL:
1020		/* allow unprivileged users to decrease the value */
1021		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1022			ret = -EPERM;
1023		else {
1024			if (val < 0)
1025				ret = -EINVAL;
1026			else
1027				sk->sk_ll_usec = val;
1028		}
1029		break;
1030#endif
1031
1032	case SO_MAX_PACING_RATE:
1033		if (val != ~0U)
1034			cmpxchg(&sk->sk_pacing_status,
1035				SK_PACING_NONE,
1036				SK_PACING_NEEDED);
1037		sk->sk_max_pacing_rate = val;
1038		sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1039					 sk->sk_max_pacing_rate);
1040		break;
1041
1042	case SO_INCOMING_CPU:
1043		sk->sk_incoming_cpu = val;
1044		break;
1045
1046	case SO_CNX_ADVICE:
1047		if (val == 1)
1048			dst_negative_advice(sk);
1049		break;
1050
1051	case SO_ZEROCOPY:
1052		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1053			if (sk->sk_protocol != IPPROTO_TCP)
1054				ret = -ENOTSUPP;
 
 
1055		} else if (sk->sk_family != PF_RDS) {
1056			ret = -ENOTSUPP;
1057		}
1058		if (!ret) {
1059			if (val < 0 || val > 1)
1060				ret = -EINVAL;
1061			else
1062				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1063		}
1064		break;
1065
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1066	default:
1067		ret = -ENOPROTOOPT;
1068		break;
1069	}
1070	release_sock(sk);
1071	return ret;
1072}
 
 
 
 
 
 
 
1073EXPORT_SYMBOL(sock_setsockopt);
1074
 
 
 
 
 
 
 
 
 
 
1075
1076static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1077			  struct ucred *ucred)
1078{
1079	ucred->pid = pid_vnr(pid);
1080	ucred->uid = ucred->gid = -1;
1081	if (cred) {
1082		struct user_namespace *current_ns = current_user_ns();
1083
1084		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1085		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1086	}
1087}
1088
1089static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1090{
1091	struct user_namespace *user_ns = current_user_ns();
1092	int i;
1093
1094	for (i = 0; i < src->ngroups; i++)
1095		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
 
 
1096			return -EFAULT;
 
1097
1098	return 0;
1099}
1100
1101int sock_getsockopt(struct socket *sock, int level, int optname,
1102		    char __user *optval, int __user *optlen)
1103{
1104	struct sock *sk = sock->sk;
1105
1106	union {
1107		int val;
1108		u64 val64;
 
1109		struct linger ling;
1110		struct timeval tm;
 
 
 
 
1111	} v;
1112
1113	int lv = sizeof(int);
1114	int len;
1115
1116	if (get_user(len, optlen))
1117		return -EFAULT;
1118	if (len < 0)
1119		return -EINVAL;
1120
1121	memset(&v, 0, sizeof(v));
1122
1123	switch (optname) {
1124	case SO_DEBUG:
1125		v.val = sock_flag(sk, SOCK_DBG);
1126		break;
1127
1128	case SO_DONTROUTE:
1129		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1130		break;
1131
1132	case SO_BROADCAST:
1133		v.val = sock_flag(sk, SOCK_BROADCAST);
1134		break;
1135
1136	case SO_SNDBUF:
1137		v.val = sk->sk_sndbuf;
1138		break;
1139
1140	case SO_RCVBUF:
1141		v.val = sk->sk_rcvbuf;
1142		break;
1143
1144	case SO_REUSEADDR:
1145		v.val = sk->sk_reuse;
1146		break;
1147
1148	case SO_REUSEPORT:
1149		v.val = sk->sk_reuseport;
1150		break;
1151
1152	case SO_KEEPALIVE:
1153		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1154		break;
1155
1156	case SO_TYPE:
1157		v.val = sk->sk_type;
1158		break;
1159
1160	case SO_PROTOCOL:
1161		v.val = sk->sk_protocol;
1162		break;
1163
1164	case SO_DOMAIN:
1165		v.val = sk->sk_family;
1166		break;
1167
1168	case SO_ERROR:
1169		v.val = -sock_error(sk);
1170		if (v.val == 0)
1171			v.val = xchg(&sk->sk_err_soft, 0);
1172		break;
1173
1174	case SO_OOBINLINE:
1175		v.val = sock_flag(sk, SOCK_URGINLINE);
1176		break;
1177
1178	case SO_NO_CHECK:
1179		v.val = sk->sk_no_check_tx;
1180		break;
1181
1182	case SO_PRIORITY:
1183		v.val = sk->sk_priority;
1184		break;
1185
1186	case SO_LINGER:
1187		lv		= sizeof(v.ling);
1188		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1189		v.ling.l_linger	= sk->sk_lingertime / HZ;
1190		break;
1191
1192	case SO_BSDCOMPAT:
1193		sock_warn_obsolete_bsdism("getsockopt");
1194		break;
1195
1196	case SO_TIMESTAMP:
1197		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
 
1198				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1199		break;
1200
1201	case SO_TIMESTAMPNS:
1202		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
 
 
 
 
1203		break;
1204
1205	case SO_TIMESTAMPING:
1206		v.val = sk->sk_tsflags;
1207		break;
1208
1209	case SO_RCVTIMEO:
1210		lv = sizeof(struct timeval);
1211		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1212			v.tm.tv_sec = 0;
1213			v.tm.tv_usec = 0;
1214		} else {
1215			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1216			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
 
 
1217		}
1218		break;
1219
1220	case SO_SNDTIMEO:
1221		lv = sizeof(struct timeval);
1222		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1223			v.tm.tv_sec = 0;
1224			v.tm.tv_usec = 0;
1225		} else {
1226			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1227			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1228		}
 
1229		break;
1230
1231	case SO_RCVLOWAT:
1232		v.val = sk->sk_rcvlowat;
1233		break;
1234
1235	case SO_SNDLOWAT:
1236		v.val = 1;
1237		break;
1238
1239	case SO_PASSCRED:
1240		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1241		break;
1242
 
 
 
 
1243	case SO_PEERCRED:
1244	{
1245		struct ucred peercred;
1246		if (len > sizeof(peercred))
1247			len = sizeof(peercred);
 
 
1248		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1249		if (copy_to_user(optval, &peercred, len))
 
 
1250			return -EFAULT;
1251		goto lenout;
1252	}
1253
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1254	case SO_PEERGROUPS:
1255	{
 
1256		int ret, n;
1257
1258		if (!sk->sk_peer_cred)
 
1259			return -ENODATA;
1260
1261		n = sk->sk_peer_cred->group_info->ngroups;
1262		if (len < n * sizeof(gid_t)) {
1263			len = n * sizeof(gid_t);
1264			return put_user(len, optlen) ? -EFAULT : -ERANGE;
 
1265		}
1266		len = n * sizeof(gid_t);
1267
1268		ret = groups_to_user((gid_t __user *)optval,
1269				     sk->sk_peer_cred->group_info);
1270		if (ret)
1271			return ret;
1272		goto lenout;
1273	}
1274
1275	case SO_PEERNAME:
1276	{
1277		char address[128];
1278
1279		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1280		if (lv < 0)
1281			return -ENOTCONN;
1282		if (lv < len)
1283			return -EINVAL;
1284		if (copy_to_user(optval, address, len))
1285			return -EFAULT;
1286		goto lenout;
1287	}
1288
1289	/* Dubious BSD thing... Probably nobody even uses it, but
1290	 * the UNIX standard wants it for whatever reason... -DaveM
1291	 */
1292	case SO_ACCEPTCONN:
1293		v.val = sk->sk_state == TCP_LISTEN;
1294		break;
1295
1296	case SO_PASSSEC:
1297		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1298		break;
1299
1300	case SO_PEERSEC:
1301		return security_socket_getpeersec_stream(sock, optval, optlen, len);
 
1302
1303	case SO_MARK:
1304		v.val = sk->sk_mark;
 
 
 
 
1305		break;
1306
1307	case SO_RXQ_OVFL:
1308		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1309		break;
1310
1311	case SO_WIFI_STATUS:
1312		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1313		break;
1314
1315	case SO_PEEK_OFF:
1316		if (!sock->ops->set_peek_off)
1317			return -EOPNOTSUPP;
1318
1319		v.val = sk->sk_peek_off;
1320		break;
1321	case SO_NOFCS:
1322		v.val = sock_flag(sk, SOCK_NOFCS);
1323		break;
1324
1325	case SO_BINDTODEVICE:
1326		return sock_getbindtodevice(sk, optval, optlen, len);
1327
1328	case SO_GET_FILTER:
1329		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1330		if (len < 0)
1331			return len;
1332
1333		goto lenout;
1334
1335	case SO_LOCK_FILTER:
1336		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1337		break;
1338
1339	case SO_BPF_EXTENSIONS:
1340		v.val = bpf_tell_extensions();
1341		break;
1342
1343	case SO_SELECT_ERR_QUEUE:
1344		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1345		break;
1346
1347#ifdef CONFIG_NET_RX_BUSY_POLL
1348	case SO_BUSY_POLL:
1349		v.val = sk->sk_ll_usec;
 
 
 
1350		break;
1351#endif
1352
1353	case SO_MAX_PACING_RATE:
1354		v.val = sk->sk_max_pacing_rate;
 
 
 
 
 
 
 
 
1355		break;
1356
1357	case SO_INCOMING_CPU:
1358		v.val = sk->sk_incoming_cpu;
1359		break;
1360
1361	case SO_MEMINFO:
1362	{
1363		u32 meminfo[SK_MEMINFO_VARS];
1364
1365		if (get_user(len, optlen))
1366			return -EFAULT;
1367
1368		sk_get_meminfo(sk, meminfo);
1369
1370		len = min_t(unsigned int, len, sizeof(meminfo));
1371		if (copy_to_user(optval, &meminfo, len))
1372			return -EFAULT;
1373
1374		goto lenout;
1375	}
1376
1377#ifdef CONFIG_NET_RX_BUSY_POLL
1378	case SO_INCOMING_NAPI_ID:
1379		v.val = READ_ONCE(sk->sk_napi_id);
1380
1381		/* aggregate non-NAPI IDs down to 0 */
1382		if (v.val < MIN_NAPI_ID)
1383			v.val = 0;
1384
1385		break;
1386#endif
1387
1388	case SO_COOKIE:
1389		lv = sizeof(u64);
1390		if (len < lv)
1391			return -EINVAL;
1392		v.val64 = sock_gen_cookie(sk);
1393		break;
1394
1395	case SO_ZEROCOPY:
1396		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1397		break;
1398
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1399	default:
1400		/* We implement the SO_SNDLOWAT etc to not be settable
1401		 * (1003.1g 7).
1402		 */
1403		return -ENOPROTOOPT;
1404	}
1405
1406	if (len > lv)
1407		len = lv;
1408	if (copy_to_user(optval, &v, len))
1409		return -EFAULT;
1410lenout:
1411	if (put_user(len, optlen))
1412		return -EFAULT;
1413	return 0;
1414}
1415
1416/*
1417 * Initialize an sk_lock.
1418 *
1419 * (We also register the sk_lock with the lock validator.)
1420 */
1421static inline void sock_lock_init(struct sock *sk)
1422{
1423	if (sk->sk_kern_sock)
1424		sock_lock_init_class_and_name(
1425			sk,
1426			af_family_kern_slock_key_strings[sk->sk_family],
1427			af_family_kern_slock_keys + sk->sk_family,
1428			af_family_kern_key_strings[sk->sk_family],
1429			af_family_kern_keys + sk->sk_family);
1430	else
1431		sock_lock_init_class_and_name(
1432			sk,
1433			af_family_slock_key_strings[sk->sk_family],
1434			af_family_slock_keys + sk->sk_family,
1435			af_family_key_strings[sk->sk_family],
1436			af_family_keys + sk->sk_family);
1437}
1438
1439/*
1440 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1441 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1442 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1443 */
1444static void sock_copy(struct sock *nsk, const struct sock *osk)
1445{
 
1446#ifdef CONFIG_SECURITY_NETWORK
1447	void *sptr = nsk->sk_security;
1448#endif
 
 
 
 
 
 
 
 
 
 
1449	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1450
1451	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1452	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
 
1453
1454#ifdef CONFIG_SECURITY_NETWORK
1455	nsk->sk_security = sptr;
1456	security_sk_clone(osk, nsk);
1457#endif
1458}
1459
1460static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1461		int family)
1462{
1463	struct sock *sk;
1464	struct kmem_cache *slab;
1465
1466	slab = prot->slab;
1467	if (slab != NULL) {
1468		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1469		if (!sk)
1470			return sk;
1471		if (priority & __GFP_ZERO)
1472			sk_prot_clear_nulls(sk, prot->obj_size);
1473	} else
1474		sk = kmalloc(prot->obj_size, priority);
1475
1476	if (sk != NULL) {
1477		if (security_sk_alloc(sk, family, priority))
1478			goto out_free;
1479
1480		if (!try_module_get(prot->owner))
1481			goto out_free_sec;
1482		sk_tx_queue_clear(sk);
1483	}
1484
1485	return sk;
1486
1487out_free_sec:
1488	security_sk_free(sk);
1489out_free:
1490	if (slab != NULL)
1491		kmem_cache_free(slab, sk);
1492	else
1493		kfree(sk);
1494	return NULL;
1495}
1496
1497static void sk_prot_free(struct proto *prot, struct sock *sk)
1498{
1499	struct kmem_cache *slab;
1500	struct module *owner;
1501
1502	owner = prot->owner;
1503	slab = prot->slab;
1504
1505	cgroup_sk_free(&sk->sk_cgrp_data);
1506	mem_cgroup_sk_free(sk);
1507	security_sk_free(sk);
1508	if (slab != NULL)
1509		kmem_cache_free(slab, sk);
1510	else
1511		kfree(sk);
1512	module_put(owner);
1513}
1514
1515/**
1516 *	sk_alloc - All socket objects are allocated here
1517 *	@net: the applicable net namespace
1518 *	@family: protocol family
1519 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1520 *	@prot: struct proto associated with this new sock instance
1521 *	@kern: is this to be a kernel socket?
1522 */
1523struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1524		      struct proto *prot, int kern)
1525{
1526	struct sock *sk;
1527
1528	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1529	if (sk) {
1530		sk->sk_family = family;
1531		/*
1532		 * See comment in struct sock definition to understand
1533		 * why we need sk_prot_creator -acme
1534		 */
1535		sk->sk_prot = sk->sk_prot_creator = prot;
1536		sk->sk_kern_sock = kern;
1537		sock_lock_init(sk);
1538		sk->sk_net_refcnt = kern ? 0 : 1;
1539		if (likely(sk->sk_net_refcnt)) {
1540			get_net(net);
1541			sock_inuse_add(net, 1);
 
 
 
 
1542		}
1543
1544		sock_net_set(sk, net);
1545		refcount_set(&sk->sk_wmem_alloc, 1);
1546
1547		mem_cgroup_sk_alloc(sk);
1548		cgroup_sk_alloc(&sk->sk_cgrp_data);
1549		sock_update_classid(&sk->sk_cgrp_data);
1550		sock_update_netprioidx(&sk->sk_cgrp_data);
 
1551	}
1552
1553	return sk;
1554}
1555EXPORT_SYMBOL(sk_alloc);
1556
1557/* Sockets having SOCK_RCU_FREE will call this function after one RCU
1558 * grace period. This is the case for UDP sockets and TCP listeners.
1559 */
1560static void __sk_destruct(struct rcu_head *head)
1561{
1562	struct sock *sk = container_of(head, struct sock, sk_rcu);
 
1563	struct sk_filter *filter;
1564
1565	if (sk->sk_destruct)
1566		sk->sk_destruct(sk);
1567
1568	filter = rcu_dereference_check(sk->sk_filter,
1569				       refcount_read(&sk->sk_wmem_alloc) == 0);
1570	if (filter) {
1571		sk_filter_uncharge(sk, filter);
1572		RCU_INIT_POINTER(sk->sk_filter, NULL);
1573	}
1574	if (rcu_access_pointer(sk->sk_reuseport_cb))
1575		reuseport_detach_sock(sk);
1576
1577	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1578
 
 
 
 
1579	if (atomic_read(&sk->sk_omem_alloc))
1580		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1581			 __func__, atomic_read(&sk->sk_omem_alloc));
1582
1583	if (sk->sk_frag.page) {
1584		put_page(sk->sk_frag.page);
1585		sk->sk_frag.page = NULL;
1586	}
1587
1588	if (sk->sk_peer_cred)
1589		put_cred(sk->sk_peer_cred);
1590	put_pid(sk->sk_peer_pid);
1591	if (likely(sk->sk_net_refcnt))
1592		put_net(sock_net(sk));
 
 
 
 
 
1593	sk_prot_free(sk->sk_prot_creator, sk);
1594}
1595
 
 
 
 
 
 
 
 
 
 
 
 
 
1596void sk_destruct(struct sock *sk)
1597{
1598	if (sock_flag(sk, SOCK_RCU_FREE))
 
 
 
 
 
 
 
1599		call_rcu(&sk->sk_rcu, __sk_destruct);
1600	else
1601		__sk_destruct(&sk->sk_rcu);
1602}
1603
1604static void __sk_free(struct sock *sk)
1605{
1606	if (likely(sk->sk_net_refcnt))
1607		sock_inuse_add(sock_net(sk), -1);
1608
1609	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1610		sock_diag_broadcast_destroy(sk);
1611	else
1612		sk_destruct(sk);
1613}
1614
1615void sk_free(struct sock *sk)
1616{
1617	/*
1618	 * We subtract one from sk_wmem_alloc and can know if
1619	 * some packets are still in some tx queue.
1620	 * If not null, sock_wfree() will call __sk_free(sk) later
1621	 */
1622	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1623		__sk_free(sk);
1624}
1625EXPORT_SYMBOL(sk_free);
1626
1627static void sk_init_common(struct sock *sk)
1628{
1629	skb_queue_head_init(&sk->sk_receive_queue);
1630	skb_queue_head_init(&sk->sk_write_queue);
1631	skb_queue_head_init(&sk->sk_error_queue);
1632
1633	rwlock_init(&sk->sk_callback_lock);
1634	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1635			af_rlock_keys + sk->sk_family,
1636			af_family_rlock_key_strings[sk->sk_family]);
1637	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1638			af_wlock_keys + sk->sk_family,
1639			af_family_wlock_key_strings[sk->sk_family]);
1640	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1641			af_elock_keys + sk->sk_family,
1642			af_family_elock_key_strings[sk->sk_family]);
1643	lockdep_set_class_and_name(&sk->sk_callback_lock,
 
 
 
 
 
1644			af_callback_keys + sk->sk_family,
1645			af_family_clock_key_strings[sk->sk_family]);
1646}
1647
1648/**
1649 *	sk_clone_lock - clone a socket, and lock its clone
1650 *	@sk: the socket to clone
1651 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1652 *
1653 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1654 */
1655struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1656{
 
 
 
1657	struct sock *newsk;
1658	bool is_charged = true;
1659
1660	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1661	if (newsk != NULL) {
1662		struct sk_filter *filter;
1663
1664		sock_copy(newsk, sk);
1665
1666		newsk->sk_prot_creator = sk->sk_prot;
1667
1668		/* SANITY */
1669		if (likely(newsk->sk_net_refcnt))
1670			get_net(sock_net(newsk));
1671		sk_node_init(&newsk->sk_node);
1672		sock_lock_init(newsk);
1673		bh_lock_sock(newsk);
1674		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1675		newsk->sk_backlog.len = 0;
1676
1677		atomic_set(&newsk->sk_rmem_alloc, 0);
1678		/*
1679		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
 
 
 
 
 
 
1680		 */
1681		refcount_set(&newsk->sk_wmem_alloc, 1);
1682		atomic_set(&newsk->sk_omem_alloc, 0);
1683		sk_init_common(newsk);
1684
1685		newsk->sk_dst_cache	= NULL;
1686		newsk->sk_dst_pending_confirm = 0;
1687		newsk->sk_wmem_queued	= 0;
1688		newsk->sk_forward_alloc = 0;
1689		atomic_set(&newsk->sk_drops, 0);
1690		newsk->sk_send_head	= NULL;
1691		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1692		atomic_set(&newsk->sk_zckey, 0);
1693
1694		sock_reset_flag(newsk, SOCK_DONE);
1695		mem_cgroup_sk_alloc(newsk);
1696		cgroup_sk_alloc(&newsk->sk_cgrp_data);
 
 
 
 
 
 
 
 
 
 
 
 
 
1697
1698		rcu_read_lock();
1699		filter = rcu_dereference(sk->sk_filter);
1700		if (filter != NULL)
1701			/* though it's an empty new sock, the charging may fail
1702			 * if sysctl_optmem_max was changed between creation of
1703			 * original socket and cloning
1704			 */
1705			is_charged = sk_filter_charge(newsk, filter);
1706		RCU_INIT_POINTER(newsk->sk_filter, filter);
1707		rcu_read_unlock();
1708
1709		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1710			/* We need to make sure that we don't uncharge the new
1711			 * socket if we couldn't charge it in the first place
1712			 * as otherwise we uncharge the parent's filter.
1713			 */
1714			if (!is_charged)
1715				RCU_INIT_POINTER(newsk->sk_filter, NULL);
1716			sk_free_unlock_clone(newsk);
1717			newsk = NULL;
1718			goto out;
1719		}
1720		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1721
1722		newsk->sk_err	   = 0;
1723		newsk->sk_err_soft = 0;
1724		newsk->sk_priority = 0;
1725		newsk->sk_incoming_cpu = raw_smp_processor_id();
1726		atomic64_set(&newsk->sk_cookie, 0);
1727		if (likely(newsk->sk_net_refcnt))
1728			sock_inuse_add(sock_net(newsk), 1);
 
 
 
1729
1730		/*
1731		 * Before updating sk_refcnt, we must commit prior changes to memory
1732		 * (Documentation/RCU/rculist_nulls.txt for details)
 
1733		 */
1734		smp_wmb();
1735		refcount_set(&newsk->sk_refcnt, 2);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1736
1737		/*
1738		 * Increment the counter in the same struct proto as the master
1739		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1740		 * is the same as sk->sk_prot->socks, as this field was copied
1741		 * with memcpy).
1742		 *
1743		 * This _changes_ the previous behaviour, where
1744		 * tcp_create_openreq_child always was incrementing the
1745		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1746		 * to be taken into account in all callers. -acme
1747		 */
1748		sk_refcnt_debug_inc(newsk);
1749		sk_set_socket(newsk, NULL);
1750		newsk->sk_wq = NULL;
1751
1752		if (newsk->sk_prot->sockets_allocated)
1753			sk_sockets_allocated_inc(newsk);
1754
1755		if (sock_needs_netstamp(sk) &&
1756		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1757			net_enable_timestamp();
1758	}
1759out:
1760	return newsk;
1761}
1762EXPORT_SYMBOL_GPL(sk_clone_lock);
1763
1764void sk_free_unlock_clone(struct sock *sk)
1765{
1766	/* It is still raw copy of parent, so invalidate
1767	 * destructor and make plain sk_free() */
1768	sk->sk_destruct = NULL;
1769	bh_unlock_sock(sk);
1770	sk_free(sk);
1771}
1772EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1773
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1774void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1775{
1776	u32 max_segs = 1;
1777
1778	sk_dst_set(sk, dst);
1779	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
 
1780	if (sk->sk_route_caps & NETIF_F_GSO)
1781		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1782	sk->sk_route_caps &= ~sk->sk_route_nocaps;
 
1783	if (sk_can_gso(sk)) {
1784		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1785			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1786		} else {
1787			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1788			sk->sk_gso_max_size = dst->dev->gso_max_size;
1789			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
 
1790		}
1791	}
1792	sk->sk_gso_max_segs = max_segs;
 
1793}
1794EXPORT_SYMBOL_GPL(sk_setup_caps);
1795
1796/*
1797 *	Simple resource managers for sockets.
1798 */
1799
1800
1801/*
1802 * Write buffer destructor automatically called from kfree_skb.
1803 */
1804void sock_wfree(struct sk_buff *skb)
1805{
1806	struct sock *sk = skb->sk;
1807	unsigned int len = skb->truesize;
 
1808
1809	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
 
 
 
 
 
 
 
 
 
 
 
1810		/*
1811		 * Keep a reference on sk_wmem_alloc, this will be released
1812		 * after sk_write_space() call
1813		 */
1814		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1815		sk->sk_write_space(sk);
1816		len = 1;
1817	}
1818	/*
1819	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1820	 * could not do because of in-flight packets
1821	 */
1822	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1823		__sk_free(sk);
1824}
1825EXPORT_SYMBOL(sock_wfree);
1826
1827/* This variant of sock_wfree() is used by TCP,
1828 * since it sets SOCK_USE_WRITE_QUEUE.
1829 */
1830void __sock_wfree(struct sk_buff *skb)
1831{
1832	struct sock *sk = skb->sk;
1833
1834	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1835		__sk_free(sk);
1836}
1837
1838void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1839{
1840	skb_orphan(skb);
1841	skb->sk = sk;
1842#ifdef CONFIG_INET
1843	if (unlikely(!sk_fullsock(sk))) {
1844		skb->destructor = sock_edemux;
1845		sock_hold(sk);
1846		return;
1847	}
1848#endif
 
1849	skb->destructor = sock_wfree;
1850	skb_set_hash_from_sk(skb, sk);
1851	/*
1852	 * We used to take a refcount on sk, but following operation
1853	 * is enough to guarantee sk_free() wont free this sock until
1854	 * all in-flight packets are completed
1855	 */
1856	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1857}
1858EXPORT_SYMBOL(skb_set_owner_w);
1859
 
 
 
 
 
 
 
 
 
 
 
 
1860/* This helper is used by netem, as it can hold packets in its
1861 * delay queue. We want to allow the owner socket to send more
1862 * packets, as if they were already TX completed by a typical driver.
1863 * But we also want to keep skb->sk set because some packet schedulers
1864 * rely on it (sch_fq for example).
1865 */
1866void skb_orphan_partial(struct sk_buff *skb)
1867{
1868	if (skb_is_tcp_pure_ack(skb))
1869		return;
1870
1871	if (skb->destructor == sock_wfree
1872#ifdef CONFIG_INET
1873	    || skb->destructor == tcp_wfree
1874#endif
1875		) {
1876		struct sock *sk = skb->sk;
1877
1878		if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1879			WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
1880			skb->destructor = sock_efree;
1881		}
1882	} else {
1883		skb_orphan(skb);
1884	}
1885}
1886EXPORT_SYMBOL(skb_orphan_partial);
1887
1888/*
1889 * Read buffer destructor automatically called from kfree_skb.
1890 */
1891void sock_rfree(struct sk_buff *skb)
1892{
1893	struct sock *sk = skb->sk;
1894	unsigned int len = skb->truesize;
1895
1896	atomic_sub(len, &sk->sk_rmem_alloc);
1897	sk_mem_uncharge(sk, len);
1898}
1899EXPORT_SYMBOL(sock_rfree);
1900
1901/*
1902 * Buffer destructor for skbs that are not used directly in read or write
1903 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1904 */
1905void sock_efree(struct sk_buff *skb)
1906{
1907	sock_put(skb->sk);
1908}
1909EXPORT_SYMBOL(sock_efree);
1910
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1911kuid_t sock_i_uid(struct sock *sk)
1912{
1913	kuid_t uid;
1914
1915	read_lock_bh(&sk->sk_callback_lock);
1916	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1917	read_unlock_bh(&sk->sk_callback_lock);
1918	return uid;
1919}
1920EXPORT_SYMBOL(sock_i_uid);
1921
 
 
 
 
 
 
 
 
 
 
 
1922unsigned long sock_i_ino(struct sock *sk)
1923{
1924	unsigned long ino;
1925
1926	read_lock_bh(&sk->sk_callback_lock);
1927	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1928	read_unlock_bh(&sk->sk_callback_lock);
1929	return ino;
1930}
1931EXPORT_SYMBOL(sock_i_ino);
1932
1933/*
1934 * Allocate a skb from the socket's send buffer.
1935 */
1936struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1937			     gfp_t priority)
1938{
1939	if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
 
1940		struct sk_buff *skb = alloc_skb(size, priority);
 
1941		if (skb) {
1942			skb_set_owner_w(skb, sk);
1943			return skb;
1944		}
1945	}
1946	return NULL;
1947}
1948EXPORT_SYMBOL(sock_wmalloc);
1949
1950static void sock_ofree(struct sk_buff *skb)
1951{
1952	struct sock *sk = skb->sk;
1953
1954	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
1955}
1956
1957struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1958			     gfp_t priority)
1959{
1960	struct sk_buff *skb;
1961
1962	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
1963	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
1964	    sysctl_optmem_max)
1965		return NULL;
1966
1967	skb = alloc_skb(size, priority);
1968	if (!skb)
1969		return NULL;
1970
1971	atomic_add(skb->truesize, &sk->sk_omem_alloc);
1972	skb->sk = sk;
1973	skb->destructor = sock_ofree;
1974	return skb;
1975}
1976
1977/*
1978 * Allocate a memory block from the socket's option memory buffer.
1979 */
1980void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1981{
1982	if ((unsigned int)size <= sysctl_optmem_max &&
1983	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
 
 
1984		void *mem;
1985		/* First do the add, to avoid the race if kmalloc
1986		 * might sleep.
1987		 */
1988		atomic_add(size, &sk->sk_omem_alloc);
1989		mem = kmalloc(size, priority);
1990		if (mem)
1991			return mem;
1992		atomic_sub(size, &sk->sk_omem_alloc);
1993	}
1994	return NULL;
1995}
1996EXPORT_SYMBOL(sock_kmalloc);
1997
1998/* Free an option memory block. Note, we actually want the inline
1999 * here as this allows gcc to detect the nullify and fold away the
2000 * condition entirely.
2001 */
2002static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2003				  const bool nullify)
2004{
2005	if (WARN_ON_ONCE(!mem))
2006		return;
2007	if (nullify)
2008		kzfree(mem);
2009	else
2010		kfree(mem);
2011	atomic_sub(size, &sk->sk_omem_alloc);
2012}
2013
2014void sock_kfree_s(struct sock *sk, void *mem, int size)
2015{
2016	__sock_kfree_s(sk, mem, size, false);
2017}
2018EXPORT_SYMBOL(sock_kfree_s);
2019
2020void sock_kzfree_s(struct sock *sk, void *mem, int size)
2021{
2022	__sock_kfree_s(sk, mem, size, true);
2023}
2024EXPORT_SYMBOL(sock_kzfree_s);
2025
2026/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2027   I think, these locks should be removed for datagram sockets.
2028 */
2029static long sock_wait_for_wmem(struct sock *sk, long timeo)
2030{
2031	DEFINE_WAIT(wait);
2032
2033	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2034	for (;;) {
2035		if (!timeo)
2036			break;
2037		if (signal_pending(current))
2038			break;
2039		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2040		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2041		if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2042			break;
2043		if (sk->sk_shutdown & SEND_SHUTDOWN)
2044			break;
2045		if (sk->sk_err)
2046			break;
2047		timeo = schedule_timeout(timeo);
2048	}
2049	finish_wait(sk_sleep(sk), &wait);
2050	return timeo;
2051}
2052
2053
2054/*
2055 *	Generic send/receive buffer handlers
2056 */
2057
2058struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2059				     unsigned long data_len, int noblock,
2060				     int *errcode, int max_page_order)
2061{
2062	struct sk_buff *skb;
2063	long timeo;
2064	int err;
2065
2066	timeo = sock_sndtimeo(sk, noblock);
2067	for (;;) {
2068		err = sock_error(sk);
2069		if (err != 0)
2070			goto failure;
2071
2072		err = -EPIPE;
2073		if (sk->sk_shutdown & SEND_SHUTDOWN)
2074			goto failure;
2075
2076		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2077			break;
2078
2079		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2080		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2081		err = -EAGAIN;
2082		if (!timeo)
2083			goto failure;
2084		if (signal_pending(current))
2085			goto interrupted;
2086		timeo = sock_wait_for_wmem(sk, timeo);
2087	}
2088	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2089				   errcode, sk->sk_allocation);
2090	if (skb)
2091		skb_set_owner_w(skb, sk);
2092	return skb;
2093
2094interrupted:
2095	err = sock_intr_errno(timeo);
2096failure:
2097	*errcode = err;
2098	return NULL;
2099}
2100EXPORT_SYMBOL(sock_alloc_send_pskb);
2101
2102struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2103				    int noblock, int *errcode)
2104{
2105	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2106}
2107EXPORT_SYMBOL(sock_alloc_send_skb);
2108
2109int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2110		     struct sockcm_cookie *sockc)
2111{
2112	u32 tsflags;
2113
 
 
2114	switch (cmsg->cmsg_type) {
2115	case SO_MARK:
2116		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 
2117			return -EPERM;
2118		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2119			return -EINVAL;
2120		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2121		break;
2122	case SO_TIMESTAMPING:
 
2123		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2124			return -EINVAL;
2125
2126		tsflags = *(u32 *)CMSG_DATA(cmsg);
2127		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2128			return -EINVAL;
2129
2130		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2131		sockc->tsflags |= tsflags;
2132		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2133	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2134	case SCM_RIGHTS:
2135	case SCM_CREDENTIALS:
2136		break;
2137	default:
2138		return -EINVAL;
2139	}
2140	return 0;
2141}
2142EXPORT_SYMBOL(__sock_cmsg_send);
2143
2144int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2145		   struct sockcm_cookie *sockc)
2146{
2147	struct cmsghdr *cmsg;
2148	int ret;
2149
2150	for_each_cmsghdr(cmsg, msg) {
2151		if (!CMSG_OK(msg, cmsg))
2152			return -EINVAL;
2153		if (cmsg->cmsg_level != SOL_SOCKET)
2154			continue;
2155		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2156		if (ret)
2157			return ret;
2158	}
2159	return 0;
2160}
2161EXPORT_SYMBOL(sock_cmsg_send);
2162
2163static void sk_enter_memory_pressure(struct sock *sk)
2164{
2165	if (!sk->sk_prot->enter_memory_pressure)
2166		return;
2167
2168	sk->sk_prot->enter_memory_pressure(sk);
2169}
2170
2171static void sk_leave_memory_pressure(struct sock *sk)
2172{
2173	if (sk->sk_prot->leave_memory_pressure) {
2174		sk->sk_prot->leave_memory_pressure(sk);
 
2175	} else {
2176		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2177
2178		if (memory_pressure && *memory_pressure)
2179			*memory_pressure = 0;
2180	}
2181}
2182
2183/* On 32bit arches, an skb frag is limited to 2^15 */
2184#define SKB_FRAG_PAGE_ORDER	get_order(32768)
2185
2186/**
2187 * skb_page_frag_refill - check that a page_frag contains enough room
2188 * @sz: minimum size of the fragment we want to get
2189 * @pfrag: pointer to page_frag
2190 * @gfp: priority for memory allocation
2191 *
2192 * Note: While this allocator tries to use high order pages, there is
2193 * no guarantee that allocations succeed. Therefore, @sz MUST be
2194 * less or equal than PAGE_SIZE.
2195 */
2196bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2197{
2198	if (pfrag->page) {
2199		if (page_ref_count(pfrag->page) == 1) {
2200			pfrag->offset = 0;
2201			return true;
2202		}
2203		if (pfrag->offset + sz <= pfrag->size)
2204			return true;
2205		put_page(pfrag->page);
2206	}
2207
2208	pfrag->offset = 0;
2209	if (SKB_FRAG_PAGE_ORDER) {
 
2210		/* Avoid direct reclaim but allow kswapd to wake */
2211		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2212					  __GFP_COMP | __GFP_NOWARN |
2213					  __GFP_NORETRY,
2214					  SKB_FRAG_PAGE_ORDER);
2215		if (likely(pfrag->page)) {
2216			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2217			return true;
2218		}
2219	}
2220	pfrag->page = alloc_page(gfp);
2221	if (likely(pfrag->page)) {
2222		pfrag->size = PAGE_SIZE;
2223		return true;
2224	}
2225	return false;
2226}
2227EXPORT_SYMBOL(skb_page_frag_refill);
2228
2229bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2230{
2231	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2232		return true;
2233
2234	sk_enter_memory_pressure(sk);
2235	sk_stream_moderate_sndbuf(sk);
2236	return false;
2237}
2238EXPORT_SYMBOL(sk_page_frag_refill);
2239
2240int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2241		int sg_start, int *sg_curr_index, unsigned int *sg_curr_size,
2242		int first_coalesce)
2243{
2244	int sg_curr = *sg_curr_index, use = 0, rc = 0;
2245	unsigned int size = *sg_curr_size;
2246	struct page_frag *pfrag;
2247	struct scatterlist *sge;
2248
2249	len -= size;
2250	pfrag = sk_page_frag(sk);
2251
2252	while (len > 0) {
2253		unsigned int orig_offset;
2254
2255		if (!sk_page_frag_refill(sk, pfrag)) {
2256			rc = -ENOMEM;
2257			goto out;
2258		}
2259
2260		use = min_t(int, len, pfrag->size - pfrag->offset);
2261
2262		if (!sk_wmem_schedule(sk, use)) {
2263			rc = -ENOMEM;
2264			goto out;
2265		}
2266
2267		sk_mem_charge(sk, use);
2268		size += use;
2269		orig_offset = pfrag->offset;
2270		pfrag->offset += use;
2271
2272		sge = sg + sg_curr - 1;
2273		if (sg_curr > first_coalesce && sg_page(sg) == pfrag->page &&
2274		    sg->offset + sg->length == orig_offset) {
2275			sg->length += use;
2276		} else {
2277			sge = sg + sg_curr;
2278			sg_unmark_end(sge);
2279			sg_set_page(sge, pfrag->page, use, orig_offset);
2280			get_page(pfrag->page);
2281			sg_curr++;
2282
2283			if (sg_curr == MAX_SKB_FRAGS)
2284				sg_curr = 0;
2285
2286			if (sg_curr == sg_start) {
2287				rc = -ENOSPC;
2288				break;
2289			}
2290		}
2291
2292		len -= use;
2293	}
2294out:
2295	*sg_curr_size = size;
2296	*sg_curr_index = sg_curr;
2297	return rc;
2298}
2299EXPORT_SYMBOL(sk_alloc_sg);
2300
2301static void __lock_sock(struct sock *sk)
2302	__releases(&sk->sk_lock.slock)
2303	__acquires(&sk->sk_lock.slock)
2304{
2305	DEFINE_WAIT(wait);
2306
2307	for (;;) {
2308		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2309					TASK_UNINTERRUPTIBLE);
2310		spin_unlock_bh(&sk->sk_lock.slock);
2311		schedule();
2312		spin_lock_bh(&sk->sk_lock.slock);
2313		if (!sock_owned_by_user(sk))
2314			break;
2315	}
2316	finish_wait(&sk->sk_lock.wq, &wait);
2317}
2318
2319static void __release_sock(struct sock *sk)
2320	__releases(&sk->sk_lock.slock)
2321	__acquires(&sk->sk_lock.slock)
2322{
2323	struct sk_buff *skb, *next;
2324
2325	while ((skb = sk->sk_backlog.head) != NULL) {
2326		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2327
2328		spin_unlock_bh(&sk->sk_lock.slock);
2329
2330		do {
2331			next = skb->next;
2332			prefetch(next);
2333			WARN_ON_ONCE(skb_dst_is_noref(skb));
2334			skb->next = NULL;
2335			sk_backlog_rcv(sk, skb);
2336
2337			cond_resched();
2338
2339			skb = next;
2340		} while (skb != NULL);
2341
2342		spin_lock_bh(&sk->sk_lock.slock);
2343	}
2344
2345	/*
2346	 * Doing the zeroing here guarantee we can not loop forever
2347	 * while a wild producer attempts to flood us.
2348	 */
2349	sk->sk_backlog.len = 0;
2350}
2351
2352void __sk_flush_backlog(struct sock *sk)
2353{
2354	spin_lock_bh(&sk->sk_lock.slock);
2355	__release_sock(sk);
 
 
 
 
 
2356	spin_unlock_bh(&sk->sk_lock.slock);
2357}
 
2358
2359/**
2360 * sk_wait_data - wait for data to arrive at sk_receive_queue
2361 * @sk:    sock to wait on
2362 * @timeo: for how long
2363 * @skb:   last skb seen on sk_receive_queue
2364 *
2365 * Now socket state including sk->sk_err is changed only under lock,
2366 * hence we may omit checks after joining wait queue.
2367 * We check receive queue before schedule() only as optimization;
2368 * it is very likely that release_sock() added new data.
2369 */
2370int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2371{
2372	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2373	int rc;
2374
2375	add_wait_queue(sk_sleep(sk), &wait);
2376	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2377	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2378	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2379	remove_wait_queue(sk_sleep(sk), &wait);
2380	return rc;
2381}
2382EXPORT_SYMBOL(sk_wait_data);
2383
2384/**
2385 *	__sk_mem_raise_allocated - increase memory_allocated
2386 *	@sk: socket
2387 *	@size: memory size to allocate
2388 *	@amt: pages to allocate
2389 *	@kind: allocation type
2390 *
2391 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
 
 
 
 
 
 
2392 */
2393int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2394{
 
2395	struct proto *prot = sk->sk_prot;
2396	long allocated = sk_memory_allocated_add(sk, amt);
 
2397
2398	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2399	    !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2400		goto suppress_allocation;
 
 
 
 
 
2401
2402	/* Under limit. */
2403	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2404		sk_leave_memory_pressure(sk);
2405		return 1;
2406	}
2407
2408	/* Under pressure. */
2409	if (allocated > sk_prot_mem_limits(sk, 1))
2410		sk_enter_memory_pressure(sk);
2411
2412	/* Over hard limit. */
2413	if (allocated > sk_prot_mem_limits(sk, 2))
2414		goto suppress_allocation;
2415
2416	/* guarantee minimum buffer size under pressure */
 
 
 
 
 
 
 
2417	if (kind == SK_MEM_RECV) {
2418		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2419			return 1;
2420
2421	} else { /* SK_MEM_SEND */
2422		int wmem0 = sk_get_wmem0(sk, prot);
2423
2424		if (sk->sk_type == SOCK_STREAM) {
2425			if (sk->sk_wmem_queued < wmem0)
2426				return 1;
2427		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2428				return 1;
2429		}
2430	}
2431
2432	if (sk_has_memory_pressure(sk)) {
2433		int alloc;
2434
2435		if (!sk_under_memory_pressure(sk))
 
 
 
 
2436			return 1;
 
 
 
 
 
2437		alloc = sk_sockets_allocated_read_positive(sk);
2438		if (sk_prot_mem_limits(sk, 2) > alloc *
2439		    sk_mem_pages(sk->sk_wmem_queued +
2440				 atomic_read(&sk->sk_rmem_alloc) +
2441				 sk->sk_forward_alloc))
2442			return 1;
2443	}
2444
2445suppress_allocation:
2446
2447	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2448		sk_stream_moderate_sndbuf(sk);
2449
2450		/* Fail only if socket is _under_ its sndbuf.
2451		 * In this case we cannot block, so that we have to fail.
2452		 */
2453		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
 
 
 
 
 
2454			return 1;
 
2455	}
2456
2457	trace_sock_exceed_buf_limit(sk, prot, allocated);
 
2458
2459	sk_memory_allocated_sub(sk, amt);
2460
2461	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2462		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2463
2464	return 0;
2465}
2466EXPORT_SYMBOL(__sk_mem_raise_allocated);
2467
2468/**
2469 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2470 *	@sk: socket
2471 *	@size: memory size to allocate
2472 *	@kind: allocation type
2473 *
2474 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2475 *	rmem allocation. This function assumes that protocols which have
2476 *	memory_pressure use sk_wmem_queued as write buffer accounting.
2477 */
2478int __sk_mem_schedule(struct sock *sk, int size, int kind)
2479{
2480	int ret, amt = sk_mem_pages(size);
2481
2482	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2483	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2484	if (!ret)
2485		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2486	return ret;
2487}
2488EXPORT_SYMBOL(__sk_mem_schedule);
2489
2490/**
2491 *	__sk_mem_reduce_allocated - reclaim memory_allocated
2492 *	@sk: socket
2493 *	@amount: number of quanta
2494 *
2495 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2496 */
2497void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2498{
2499	sk_memory_allocated_sub(sk, amount);
2500
2501	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2502		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2503
2504	if (sk_under_memory_pressure(sk) &&
2505	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2506		sk_leave_memory_pressure(sk);
2507}
2508EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2509
2510/**
2511 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2512 *	@sk: socket
2513 *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2514 */
2515void __sk_mem_reclaim(struct sock *sk, int amount)
2516{
2517	amount >>= SK_MEM_QUANTUM_SHIFT;
2518	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2519	__sk_mem_reduce_allocated(sk, amount);
2520}
2521EXPORT_SYMBOL(__sk_mem_reclaim);
2522
2523int sk_set_peek_off(struct sock *sk, int val)
2524{
2525	sk->sk_peek_off = val;
2526	return 0;
2527}
2528EXPORT_SYMBOL_GPL(sk_set_peek_off);
2529
2530/*
2531 * Set of default routines for initialising struct proto_ops when
2532 * the protocol does not support a particular function. In certain
2533 * cases where it makes no sense for a protocol to have a "do nothing"
2534 * function, some default processing is provided.
2535 */
2536
2537int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2538{
2539	return -EOPNOTSUPP;
2540}
2541EXPORT_SYMBOL(sock_no_bind);
2542
2543int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2544		    int len, int flags)
2545{
2546	return -EOPNOTSUPP;
2547}
2548EXPORT_SYMBOL(sock_no_connect);
2549
2550int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2551{
2552	return -EOPNOTSUPP;
2553}
2554EXPORT_SYMBOL(sock_no_socketpair);
2555
2556int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2557		   bool kern)
2558{
2559	return -EOPNOTSUPP;
2560}
2561EXPORT_SYMBOL(sock_no_accept);
2562
2563int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2564		    int peer)
2565{
2566	return -EOPNOTSUPP;
2567}
2568EXPORT_SYMBOL(sock_no_getname);
2569
2570__poll_t sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2571{
2572	return 0;
2573}
2574EXPORT_SYMBOL(sock_no_poll);
2575
2576int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2577{
2578	return -EOPNOTSUPP;
2579}
2580EXPORT_SYMBOL(sock_no_ioctl);
2581
2582int sock_no_listen(struct socket *sock, int backlog)
2583{
2584	return -EOPNOTSUPP;
2585}
2586EXPORT_SYMBOL(sock_no_listen);
2587
2588int sock_no_shutdown(struct socket *sock, int how)
2589{
2590	return -EOPNOTSUPP;
2591}
2592EXPORT_SYMBOL(sock_no_shutdown);
2593
2594int sock_no_setsockopt(struct socket *sock, int level, int optname,
2595		    char __user *optval, unsigned int optlen)
2596{
2597	return -EOPNOTSUPP;
2598}
2599EXPORT_SYMBOL(sock_no_setsockopt);
2600
2601int sock_no_getsockopt(struct socket *sock, int level, int optname,
2602		    char __user *optval, int __user *optlen)
2603{
2604	return -EOPNOTSUPP;
2605}
2606EXPORT_SYMBOL(sock_no_getsockopt);
2607
2608int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2609{
2610	return -EOPNOTSUPP;
2611}
2612EXPORT_SYMBOL(sock_no_sendmsg);
2613
2614int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2615{
2616	return -EOPNOTSUPP;
2617}
2618EXPORT_SYMBOL(sock_no_sendmsg_locked);
2619
2620int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2621		    int flags)
2622{
2623	return -EOPNOTSUPP;
2624}
2625EXPORT_SYMBOL(sock_no_recvmsg);
2626
2627int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2628{
2629	/* Mirror missing mmap method error code */
2630	return -ENODEV;
2631}
2632EXPORT_SYMBOL(sock_no_mmap);
2633
2634ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
 
 
 
 
2635{
2636	ssize_t res;
2637	struct msghdr msg = {.msg_flags = flags};
2638	struct kvec iov;
2639	char *kaddr = kmap(page);
2640	iov.iov_base = kaddr + offset;
2641	iov.iov_len = size;
2642	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2643	kunmap(page);
2644	return res;
2645}
2646EXPORT_SYMBOL(sock_no_sendpage);
2647
2648ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2649				int offset, size_t size, int flags)
2650{
2651	ssize_t res;
2652	struct msghdr msg = {.msg_flags = flags};
2653	struct kvec iov;
2654	char *kaddr = kmap(page);
2655
2656	iov.iov_base = kaddr + offset;
2657	iov.iov_len = size;
2658	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2659	kunmap(page);
2660	return res;
2661}
2662EXPORT_SYMBOL(sock_no_sendpage_locked);
2663
2664/*
2665 *	Default Socket Callbacks
2666 */
2667
2668static void sock_def_wakeup(struct sock *sk)
2669{
2670	struct socket_wq *wq;
2671
2672	rcu_read_lock();
2673	wq = rcu_dereference(sk->sk_wq);
2674	if (skwq_has_sleeper(wq))
2675		wake_up_interruptible_all(&wq->wait);
2676	rcu_read_unlock();
2677}
2678
2679static void sock_def_error_report(struct sock *sk)
2680{
2681	struct socket_wq *wq;
2682
2683	rcu_read_lock();
2684	wq = rcu_dereference(sk->sk_wq);
2685	if (skwq_has_sleeper(wq))
2686		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2687	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2688	rcu_read_unlock();
2689}
2690
2691static void sock_def_readable(struct sock *sk)
2692{
2693	struct socket_wq *wq;
2694
 
 
2695	rcu_read_lock();
2696	wq = rcu_dereference(sk->sk_wq);
2697	if (skwq_has_sleeper(wq))
2698		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2699						EPOLLRDNORM | EPOLLRDBAND);
2700	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2701	rcu_read_unlock();
2702}
2703
2704static void sock_def_write_space(struct sock *sk)
2705{
2706	struct socket_wq *wq;
2707
2708	rcu_read_lock();
2709
2710	/* Do not wake up a writer until he can make "significant"
2711	 * progress.  --DaveM
2712	 */
2713	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2714		wq = rcu_dereference(sk->sk_wq);
2715		if (skwq_has_sleeper(wq))
2716			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2717						EPOLLWRNORM | EPOLLWRBAND);
2718
2719		/* Should agree with poll, otherwise some programs break */
2720		if (sock_writeable(sk))
2721			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2722	}
2723
2724	rcu_read_unlock();
2725}
2726
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2727static void sock_def_destruct(struct sock *sk)
2728{
2729}
2730
2731void sk_send_sigurg(struct sock *sk)
2732{
2733	if (sk->sk_socket && sk->sk_socket->file)
2734		if (send_sigurg(&sk->sk_socket->file->f_owner))
2735			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2736}
2737EXPORT_SYMBOL(sk_send_sigurg);
2738
2739void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2740		    unsigned long expires)
2741{
2742	if (!mod_timer(timer, expires))
2743		sock_hold(sk);
2744}
2745EXPORT_SYMBOL(sk_reset_timer);
2746
2747void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2748{
2749	if (del_timer(timer))
2750		__sock_put(sk);
2751}
2752EXPORT_SYMBOL(sk_stop_timer);
2753
2754void sock_init_data(struct socket *sock, struct sock *sk)
 
 
 
 
 
 
 
2755{
2756	sk_init_common(sk);
2757	sk->sk_send_head	=	NULL;
2758
2759	timer_setup(&sk->sk_timer, NULL, 0);
2760
2761	sk->sk_allocation	=	GFP_KERNEL;
2762	sk->sk_rcvbuf		=	sysctl_rmem_default;
2763	sk->sk_sndbuf		=	sysctl_wmem_default;
2764	sk->sk_state		=	TCP_CLOSE;
 
2765	sk_set_socket(sk, sock);
2766
2767	sock_set_flag(sk, SOCK_ZAPPED);
2768
2769	if (sock) {
2770		sk->sk_type	=	sock->type;
2771		sk->sk_wq	=	sock->wq;
2772		sock->sk	=	sk;
2773		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2774	} else {
2775		sk->sk_wq	=	NULL;
2776		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2777	}
2778
2779	rwlock_init(&sk->sk_callback_lock);
2780	if (sk->sk_kern_sock)
2781		lockdep_set_class_and_name(
2782			&sk->sk_callback_lock,
2783			af_kern_callback_keys + sk->sk_family,
2784			af_family_kern_clock_key_strings[sk->sk_family]);
2785	else
2786		lockdep_set_class_and_name(
2787			&sk->sk_callback_lock,
2788			af_callback_keys + sk->sk_family,
2789			af_family_clock_key_strings[sk->sk_family]);
2790
2791	sk->sk_state_change	=	sock_def_wakeup;
2792	sk->sk_data_ready	=	sock_def_readable;
2793	sk->sk_write_space	=	sock_def_write_space;
2794	sk->sk_error_report	=	sock_def_error_report;
2795	sk->sk_destruct		=	sock_def_destruct;
2796
2797	sk->sk_frag.page	=	NULL;
2798	sk->sk_frag.offset	=	0;
2799	sk->sk_peek_off		=	-1;
2800
2801	sk->sk_peer_pid 	=	NULL;
2802	sk->sk_peer_cred	=	NULL;
 
 
2803	sk->sk_write_pending	=	0;
2804	sk->sk_rcvlowat		=	1;
2805	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2806	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2807
2808	sk->sk_stamp = SK_DEFAULT_STAMP;
 
 
 
2809	atomic_set(&sk->sk_zckey, 0);
2810
2811#ifdef CONFIG_NET_RX_BUSY_POLL
2812	sk->sk_napi_id		=	0;
2813	sk->sk_ll_usec		=	sysctl_net_busy_read;
2814#endif
2815
2816	sk->sk_max_pacing_rate = ~0U;
2817	sk->sk_pacing_rate = ~0U;
2818	sk->sk_pacing_shift = 10;
2819	sk->sk_incoming_cpu = -1;
 
 
2820	/*
2821	 * Before updating sk_refcnt, we must commit prior changes to memory
2822	 * (Documentation/RCU/rculist_nulls.txt for details)
2823	 */
2824	smp_wmb();
2825	refcount_set(&sk->sk_refcnt, 1);
2826	atomic_set(&sk->sk_drops, 0);
2827}
 
 
 
 
 
 
 
 
 
 
2828EXPORT_SYMBOL(sock_init_data);
2829
2830void lock_sock_nested(struct sock *sk, int subclass)
2831{
 
 
 
2832	might_sleep();
2833	spin_lock_bh(&sk->sk_lock.slock);
2834	if (sk->sk_lock.owned)
2835		__lock_sock(sk);
2836	sk->sk_lock.owned = 1;
2837	spin_unlock(&sk->sk_lock.slock);
2838	/*
2839	 * The sk_lock has mutex_lock() semantics here:
2840	 */
2841	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2842	local_bh_enable();
2843}
2844EXPORT_SYMBOL(lock_sock_nested);
2845
2846void release_sock(struct sock *sk)
2847{
2848	spin_lock_bh(&sk->sk_lock.slock);
2849	if (sk->sk_backlog.tail)
2850		__release_sock(sk);
2851
2852	/* Warning : release_cb() might need to release sk ownership,
2853	 * ie call sock_release_ownership(sk) before us.
2854	 */
2855	if (sk->sk_prot->release_cb)
2856		sk->sk_prot->release_cb(sk);
 
2857
2858	sock_release_ownership(sk);
2859	if (waitqueue_active(&sk->sk_lock.wq))
2860		wake_up(&sk->sk_lock.wq);
2861	spin_unlock_bh(&sk->sk_lock.slock);
2862}
2863EXPORT_SYMBOL(release_sock);
2864
2865/**
2866 * lock_sock_fast - fast version of lock_sock
2867 * @sk: socket
2868 *
2869 * This version should be used for very small section, where process wont block
2870 * return false if fast path is taken:
2871 *
2872 *   sk_lock.slock locked, owned = 0, BH disabled
2873 *
2874 * return true if slow path is taken:
2875 *
2876 *   sk_lock.slock unlocked, owned = 1, BH enabled
2877 */
2878bool lock_sock_fast(struct sock *sk)
2879{
2880	might_sleep();
2881	spin_lock_bh(&sk->sk_lock.slock);
2882
2883	if (!sk->sk_lock.owned)
2884		/*
2885		 * Note : We must disable BH
 
 
 
 
 
 
 
 
 
 
 
 
2886		 */
2887		return false;
 
2888
2889	__lock_sock(sk);
2890	sk->sk_lock.owned = 1;
2891	spin_unlock(&sk->sk_lock.slock);
2892	/*
2893	 * The sk_lock has mutex_lock() semantics here:
2894	 */
2895	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2896	local_bh_enable();
2897	return true;
2898}
2899EXPORT_SYMBOL(lock_sock_fast);
2900
2901int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
 
2902{
2903	struct timeval tv;
2904	if (!sock_flag(sk, SOCK_TIMESTAMP))
2905		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2906	tv = ktime_to_timeval(sk->sk_stamp);
2907	if (tv.tv_sec == -1)
2908		return -ENOENT;
2909	if (tv.tv_sec == 0) {
2910		sk->sk_stamp = ktime_get_real();
2911		tv = ktime_to_timeval(sk->sk_stamp);
2912	}
2913	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2914}
2915EXPORT_SYMBOL(sock_get_timestamp);
2916
2917int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2918{
2919	struct timespec ts;
2920	if (!sock_flag(sk, SOCK_TIMESTAMP))
2921		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2922	ts = ktime_to_timespec(sk->sk_stamp);
2923	if (ts.tv_sec == -1)
2924		return -ENOENT;
2925	if (ts.tv_sec == 0) {
2926		sk->sk_stamp = ktime_get_real();
2927		ts = ktime_to_timespec(sk->sk_stamp);
 
2928	}
2929	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2930}
2931EXPORT_SYMBOL(sock_get_timestampns);
2932
2933void sock_enable_timestamp(struct sock *sk, int flag)
2934{
2935	if (!sock_flag(sk, flag)) {
2936		unsigned long previous_flags = sk->sk_flags;
2937
2938		sock_set_flag(sk, flag);
2939		/*
2940		 * we just set one of the two flags which require net
2941		 * time stamping, but time stamping might have been on
2942		 * already because of the other one
2943		 */
2944		if (sock_needs_netstamp(sk) &&
2945		    !(previous_flags & SK_FLAGS_TIMESTAMP))
2946			net_enable_timestamp();
2947	}
2948}
2949
2950int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2951		       int level, int type)
2952{
2953	struct sock_exterr_skb *serr;
2954	struct sk_buff *skb;
2955	int copied, err;
2956
2957	err = -EAGAIN;
2958	skb = sock_dequeue_err_skb(sk);
2959	if (skb == NULL)
2960		goto out;
2961
2962	copied = skb->len;
2963	if (copied > len) {
2964		msg->msg_flags |= MSG_TRUNC;
2965		copied = len;
2966	}
2967	err = skb_copy_datagram_msg(skb, 0, msg, copied);
2968	if (err)
2969		goto out_free_skb;
2970
2971	sock_recv_timestamp(msg, sk, skb);
2972
2973	serr = SKB_EXT_ERR(skb);
2974	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2975
2976	msg->msg_flags |= MSG_ERRQUEUE;
2977	err = copied;
2978
2979out_free_skb:
2980	kfree_skb(skb);
2981out:
2982	return err;
2983}
2984EXPORT_SYMBOL(sock_recv_errqueue);
2985
2986/*
2987 *	Get a socket option on an socket.
2988 *
2989 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2990 *	asynchronous errors should be reported by getsockopt. We assume
2991 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2992 */
2993int sock_common_getsockopt(struct socket *sock, int level, int optname,
2994			   char __user *optval, int __user *optlen)
2995{
2996	struct sock *sk = sock->sk;
2997
2998	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
 
2999}
3000EXPORT_SYMBOL(sock_common_getsockopt);
3001
3002#ifdef CONFIG_COMPAT
3003int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
3004				  char __user *optval, int __user *optlen)
3005{
3006	struct sock *sk = sock->sk;
3007
3008	if (sk->sk_prot->compat_getsockopt != NULL)
3009		return sk->sk_prot->compat_getsockopt(sk, level, optname,
3010						      optval, optlen);
3011	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3012}
3013EXPORT_SYMBOL(compat_sock_common_getsockopt);
3014#endif
3015
3016int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3017			int flags)
3018{
3019	struct sock *sk = sock->sk;
3020	int addr_len = 0;
3021	int err;
3022
3023	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3024				   flags & ~MSG_DONTWAIT, &addr_len);
3025	if (err >= 0)
3026		msg->msg_namelen = addr_len;
3027	return err;
3028}
3029EXPORT_SYMBOL(sock_common_recvmsg);
3030
3031/*
3032 *	Set socket options on an inet socket.
3033 */
3034int sock_common_setsockopt(struct socket *sock, int level, int optname,
3035			   char __user *optval, unsigned int optlen)
3036{
3037	struct sock *sk = sock->sk;
3038
3039	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
 
3040}
3041EXPORT_SYMBOL(sock_common_setsockopt);
3042
3043#ifdef CONFIG_COMPAT
3044int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
3045				  char __user *optval, unsigned int optlen)
3046{
3047	struct sock *sk = sock->sk;
3048
3049	if (sk->sk_prot->compat_setsockopt != NULL)
3050		return sk->sk_prot->compat_setsockopt(sk, level, optname,
3051						      optval, optlen);
3052	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3053}
3054EXPORT_SYMBOL(compat_sock_common_setsockopt);
3055#endif
3056
3057void sk_common_release(struct sock *sk)
3058{
3059	if (sk->sk_prot->destroy)
3060		sk->sk_prot->destroy(sk);
3061
3062	/*
3063	 * Observation: when sock_common_release is called, processes have
3064	 * no access to socket. But net still has.
3065	 * Step one, detach it from networking:
3066	 *
3067	 * A. Remove from hash tables.
3068	 */
3069
3070	sk->sk_prot->unhash(sk);
3071
3072	/*
3073	 * In this point socket cannot receive new packets, but it is possible
3074	 * that some packets are in flight because some CPU runs receiver and
3075	 * did hash table lookup before we unhashed socket. They will achieve
3076	 * receive queue and will be purged by socket destructor.
3077	 *
3078	 * Also we still have packets pending on receive queue and probably,
3079	 * our own packets waiting in device queues. sock_destroy will drain
3080	 * receive queue, but transmitted packets will delay socket destruction
3081	 * until the last reference will be released.
3082	 */
3083
3084	sock_orphan(sk);
3085
3086	xfrm_sk_free_policy(sk);
3087
3088	sk_refcnt_debug_release(sk);
3089
3090	sock_put(sk);
3091}
3092EXPORT_SYMBOL(sk_common_release);
3093
3094void sk_get_meminfo(const struct sock *sk, u32 *mem)
3095{
3096	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3097
3098	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3099	mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3100	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3101	mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3102	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3103	mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3104	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3105	mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3106	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3107}
3108
3109#ifdef CONFIG_PROC_FS
3110#define PROTO_INUSE_NR	64	/* should be enough for the first time */
3111struct prot_inuse {
3112	int val[PROTO_INUSE_NR];
3113};
3114
3115static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3116
3117void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3118{
3119	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3120}
3121EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3122
3123int sock_prot_inuse_get(struct net *net, struct proto *prot)
3124{
3125	int cpu, idx = prot->inuse_idx;
3126	int res = 0;
3127
3128	for_each_possible_cpu(cpu)
3129		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3130
3131	return res >= 0 ? res : 0;
3132}
3133EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3134
3135static void sock_inuse_add(struct net *net, int val)
3136{
3137	this_cpu_add(*net->core.sock_inuse, val);
3138}
3139
3140int sock_inuse_get(struct net *net)
3141{
3142	int cpu, res = 0;
3143
3144	for_each_possible_cpu(cpu)
3145		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3146
3147	return res;
3148}
3149
3150EXPORT_SYMBOL_GPL(sock_inuse_get);
3151
3152static int __net_init sock_inuse_init_net(struct net *net)
3153{
3154	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3155	if (net->core.prot_inuse == NULL)
3156		return -ENOMEM;
3157
3158	net->core.sock_inuse = alloc_percpu(int);
3159	if (net->core.sock_inuse == NULL)
3160		goto out;
3161
3162	return 0;
3163
3164out:
3165	free_percpu(net->core.prot_inuse);
3166	return -ENOMEM;
3167}
3168
3169static void __net_exit sock_inuse_exit_net(struct net *net)
3170{
3171	free_percpu(net->core.prot_inuse);
3172	free_percpu(net->core.sock_inuse);
3173}
3174
3175static struct pernet_operations net_inuse_ops = {
3176	.init = sock_inuse_init_net,
3177	.exit = sock_inuse_exit_net,
3178};
3179
3180static __init int net_inuse_init(void)
3181{
3182	if (register_pernet_subsys(&net_inuse_ops))
3183		panic("Cannot initialize net inuse counters");
3184
3185	return 0;
3186}
3187
3188core_initcall(net_inuse_init);
3189
3190static void assign_proto_idx(struct proto *prot)
3191{
3192	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3193
3194	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3195		pr_err("PROTO_INUSE_NR exhausted\n");
3196		return;
3197	}
3198
3199	set_bit(prot->inuse_idx, proto_inuse_idx);
 
3200}
3201
3202static void release_proto_idx(struct proto *prot)
3203{
3204	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3205		clear_bit(prot->inuse_idx, proto_inuse_idx);
3206}
3207#else
3208static inline void assign_proto_idx(struct proto *prot)
3209{
 
3210}
3211
3212static inline void release_proto_idx(struct proto *prot)
3213{
3214}
3215
3216static void sock_inuse_add(struct net *net, int val)
 
 
3217{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3218}
3219#endif
3220
3221static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3222{
3223	if (!rsk_prot)
3224		return;
3225	kfree(rsk_prot->slab_name);
3226	rsk_prot->slab_name = NULL;
3227	kmem_cache_destroy(rsk_prot->slab);
3228	rsk_prot->slab = NULL;
3229}
3230
3231static int req_prot_init(const struct proto *prot)
3232{
3233	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3234
3235	if (!rsk_prot)
3236		return 0;
3237
3238	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3239					prot->name);
3240	if (!rsk_prot->slab_name)
3241		return -ENOMEM;
3242
3243	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3244					   rsk_prot->obj_size, 0,
3245					   prot->slab_flags, NULL);
 
3246
3247	if (!rsk_prot->slab) {
3248		pr_crit("%s: Can't create request sock SLAB cache!\n",
3249			prot->name);
3250		return -ENOMEM;
3251	}
3252	return 0;
3253}
3254
3255int proto_register(struct proto *prot, int alloc_slab)
3256{
 
 
 
 
 
 
 
 
 
 
3257	if (alloc_slab) {
3258		prot->slab = kmem_cache_create_usercopy(prot->name,
3259					prot->obj_size, 0,
3260					SLAB_HWCACHE_ALIGN | prot->slab_flags,
 
3261					prot->useroffset, prot->usersize,
3262					NULL);
3263
3264		if (prot->slab == NULL) {
3265			pr_crit("%s: Can't create sock SLAB cache!\n",
3266				prot->name);
3267			goto out;
3268		}
3269
3270		if (req_prot_init(prot))
3271			goto out_free_request_sock_slab;
3272
3273		if (prot->twsk_prot != NULL) {
3274			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3275
3276			if (prot->twsk_prot->twsk_slab_name == NULL)
3277				goto out_free_request_sock_slab;
3278
3279			prot->twsk_prot->twsk_slab =
3280				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3281						  prot->twsk_prot->twsk_obj_size,
3282						  0,
3283						  prot->slab_flags,
3284						  NULL);
3285			if (prot->twsk_prot->twsk_slab == NULL)
3286				goto out_free_timewait_sock_slab_name;
3287		}
3288	}
3289
3290	mutex_lock(&proto_list_mutex);
 
 
 
 
 
3291	list_add(&prot->node, &proto_list);
3292	assign_proto_idx(prot);
3293	mutex_unlock(&proto_list_mutex);
3294	return 0;
3295
3296out_free_timewait_sock_slab_name:
3297	kfree(prot->twsk_prot->twsk_slab_name);
 
3298out_free_request_sock_slab:
3299	req_prot_cleanup(prot->rsk_prot);
 
3300
3301	kmem_cache_destroy(prot->slab);
3302	prot->slab = NULL;
 
3303out:
3304	return -ENOBUFS;
3305}
3306EXPORT_SYMBOL(proto_register);
3307
3308void proto_unregister(struct proto *prot)
3309{
3310	mutex_lock(&proto_list_mutex);
3311	release_proto_idx(prot);
3312	list_del(&prot->node);
3313	mutex_unlock(&proto_list_mutex);
3314
3315	kmem_cache_destroy(prot->slab);
3316	prot->slab = NULL;
3317
3318	req_prot_cleanup(prot->rsk_prot);
3319
3320	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3321		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3322		kfree(prot->twsk_prot->twsk_slab_name);
3323		prot->twsk_prot->twsk_slab = NULL;
3324	}
3325}
3326EXPORT_SYMBOL(proto_unregister);
3327
3328int sock_load_diag_module(int family, int protocol)
3329{
3330	if (!protocol) {
3331		if (!sock_is_registered(family))
3332			return -ENOENT;
3333
3334		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3335				      NETLINK_SOCK_DIAG, family);
3336	}
3337
3338#ifdef CONFIG_INET
3339	if (family == AF_INET &&
 
 
3340	    !rcu_access_pointer(inet_protos[protocol]))
3341		return -ENOENT;
3342#endif
3343
3344	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3345			      NETLINK_SOCK_DIAG, family, protocol);
3346}
3347EXPORT_SYMBOL(sock_load_diag_module);
3348
3349#ifdef CONFIG_PROC_FS
3350static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3351	__acquires(proto_list_mutex)
3352{
3353	mutex_lock(&proto_list_mutex);
3354	return seq_list_start_head(&proto_list, *pos);
3355}
3356
3357static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3358{
3359	return seq_list_next(v, &proto_list, pos);
3360}
3361
3362static void proto_seq_stop(struct seq_file *seq, void *v)
3363	__releases(proto_list_mutex)
3364{
3365	mutex_unlock(&proto_list_mutex);
3366}
3367
3368static char proto_method_implemented(const void *method)
3369{
3370	return method == NULL ? 'n' : 'y';
3371}
3372static long sock_prot_memory_allocated(struct proto *proto)
3373{
3374	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3375}
3376
3377static char *sock_prot_memory_pressure(struct proto *proto)
3378{
3379	return proto->memory_pressure != NULL ?
3380	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3381}
3382
3383static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3384{
3385
3386	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3387			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3388		   proto->name,
3389		   proto->obj_size,
3390		   sock_prot_inuse_get(seq_file_net(seq), proto),
3391		   sock_prot_memory_allocated(proto),
3392		   sock_prot_memory_pressure(proto),
3393		   proto->max_header,
3394		   proto->slab == NULL ? "no" : "yes",
3395		   module_name(proto->owner),
3396		   proto_method_implemented(proto->close),
3397		   proto_method_implemented(proto->connect),
3398		   proto_method_implemented(proto->disconnect),
3399		   proto_method_implemented(proto->accept),
3400		   proto_method_implemented(proto->ioctl),
3401		   proto_method_implemented(proto->init),
3402		   proto_method_implemented(proto->destroy),
3403		   proto_method_implemented(proto->shutdown),
3404		   proto_method_implemented(proto->setsockopt),
3405		   proto_method_implemented(proto->getsockopt),
3406		   proto_method_implemented(proto->sendmsg),
3407		   proto_method_implemented(proto->recvmsg),
3408		   proto_method_implemented(proto->sendpage),
3409		   proto_method_implemented(proto->bind),
3410		   proto_method_implemented(proto->backlog_rcv),
3411		   proto_method_implemented(proto->hash),
3412		   proto_method_implemented(proto->unhash),
3413		   proto_method_implemented(proto->get_port),
3414		   proto_method_implemented(proto->enter_memory_pressure));
3415}
3416
3417static int proto_seq_show(struct seq_file *seq, void *v)
3418{
3419	if (v == &proto_list)
3420		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3421			   "protocol",
3422			   "size",
3423			   "sockets",
3424			   "memory",
3425			   "press",
3426			   "maxhdr",
3427			   "slab",
3428			   "module",
3429			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3430	else
3431		proto_seq_printf(seq, list_entry(v, struct proto, node));
3432	return 0;
3433}
3434
3435static const struct seq_operations proto_seq_ops = {
3436	.start  = proto_seq_start,
3437	.next   = proto_seq_next,
3438	.stop   = proto_seq_stop,
3439	.show   = proto_seq_show,
3440};
3441
3442static int proto_seq_open(struct inode *inode, struct file *file)
3443{
3444	return seq_open_net(inode, file, &proto_seq_ops,
3445			    sizeof(struct seq_net_private));
3446}
3447
3448static const struct file_operations proto_seq_fops = {
3449	.open		= proto_seq_open,
3450	.read		= seq_read,
3451	.llseek		= seq_lseek,
3452	.release	= seq_release_net,
3453};
3454
3455static __net_init int proto_init_net(struct net *net)
3456{
3457	if (!proc_create("protocols", 0444, net->proc_net, &proto_seq_fops))
 
3458		return -ENOMEM;
3459
3460	return 0;
3461}
3462
3463static __net_exit void proto_exit_net(struct net *net)
3464{
3465	remove_proc_entry("protocols", net->proc_net);
3466}
3467
3468
3469static __net_initdata struct pernet_operations proto_net_ops = {
3470	.init = proto_init_net,
3471	.exit = proto_exit_net,
3472};
3473
3474static int __init proto_init(void)
3475{
3476	return register_pernet_subsys(&proto_net_ops);
3477}
3478
3479subsys_initcall(proto_init);
3480
3481#endif /* PROC_FS */
3482
3483#ifdef CONFIG_NET_RX_BUSY_POLL
3484bool sk_busy_loop_end(void *p, unsigned long start_time)
3485{
3486	struct sock *sk = p;
3487
3488	return !skb_queue_empty(&sk->sk_receive_queue) ||
3489	       sk_busy_loop_timeout(sk, start_time);
 
 
 
 
 
 
3490}
3491EXPORT_SYMBOL(sk_busy_loop_end);
3492#endif /* CONFIG_NET_RX_BUSY_POLL */