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v5.9
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   4 *		operating system.  INET is implemented using the  BSD Socket
   5 *		interface as the means of communication with the user level.
   6 *
   7 *		Generic socket support routines. Memory allocators, socket lock/release
   8 *		handler for protocols to use and generic option handler.
   9 *
 
  10 * Authors:	Ross Biro
  11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *		Florian La Roche, <flla@stud.uni-sb.de>
  13 *		Alan Cox, <A.Cox@swansea.ac.uk>
  14 *
  15 * Fixes:
  16 *		Alan Cox	: 	Numerous verify_area() problems
  17 *		Alan Cox	:	Connecting on a connecting socket
  18 *					now returns an error for tcp.
  19 *		Alan Cox	:	sock->protocol is set correctly.
  20 *					and is not sometimes left as 0.
  21 *		Alan Cox	:	connect handles icmp errors on a
  22 *					connect properly. Unfortunately there
  23 *					is a restart syscall nasty there. I
  24 *					can't match BSD without hacking the C
  25 *					library. Ideas urgently sought!
  26 *		Alan Cox	:	Disallow bind() to addresses that are
  27 *					not ours - especially broadcast ones!!
  28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
  29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
  30 *					instead they leave that for the DESTROY timer.
  31 *		Alan Cox	:	Clean up error flag in accept
  32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
  33 *					was buggy. Put a remove_sock() in the handler
  34 *					for memory when we hit 0. Also altered the timer
  35 *					code. The ACK stuff can wait and needs major
  36 *					TCP layer surgery.
  37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
  38 *					and fixed timer/inet_bh race.
  39 *		Alan Cox	:	Added zapped flag for TCP
  40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
  41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
  42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
  43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
  44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
  45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
  46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
  47 *	Pauline Middelink	:	identd support
  48 *		Alan Cox	:	Fixed connect() taking signals I think.
  49 *		Alan Cox	:	SO_LINGER supported
  50 *		Alan Cox	:	Error reporting fixes
  51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
  52 *		Alan Cox	:	inet sockets don't set sk->type!
  53 *		Alan Cox	:	Split socket option code
  54 *		Alan Cox	:	Callbacks
  55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
  56 *		Alex		:	Removed restriction on inet fioctl
  57 *		Alan Cox	:	Splitting INET from NET core
  58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
  59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
  60 *		Alan Cox	:	Split IP from generic code
  61 *		Alan Cox	:	New kfree_skbmem()
  62 *		Alan Cox	:	Make SO_DEBUG superuser only.
  63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
  64 *					(compatibility fix)
  65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
  66 *		Alan Cox	:	Allocator for a socket is settable.
  67 *		Alan Cox	:	SO_ERROR includes soft errors.
  68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
  69 *		Alan Cox	: 	Generic socket allocation to make hooks
  70 *					easier (suggested by Craig Metz).
  71 *		Michael Pall	:	SO_ERROR returns positive errno again
  72 *              Steve Whitehouse:       Added default destructor to free
  73 *                                      protocol private data.
  74 *              Steve Whitehouse:       Added various other default routines
  75 *                                      common to several socket families.
  76 *              Chris Evans     :       Call suser() check last on F_SETOWN
  77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
  78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
  79 *		Andi Kleen	:	Fix write_space callback
  80 *		Chris Evans	:	Security fixes - signedness again
  81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
  82 *
  83 * To Fix:
 
 
 
 
 
 
  84 */
  85
  86#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  87
  88#include <asm/unaligned.h>
  89#include <linux/capability.h>
  90#include <linux/errno.h>
  91#include <linux/errqueue.h>
  92#include <linux/types.h>
  93#include <linux/socket.h>
  94#include <linux/in.h>
  95#include <linux/kernel.h>
  96#include <linux/module.h>
  97#include <linux/proc_fs.h>
  98#include <linux/seq_file.h>
  99#include <linux/sched.h>
 100#include <linux/sched/mm.h>
 101#include <linux/timer.h>
 102#include <linux/string.h>
 103#include <linux/sockios.h>
 104#include <linux/net.h>
 105#include <linux/mm.h>
 106#include <linux/slab.h>
 107#include <linux/interrupt.h>
 108#include <linux/poll.h>
 109#include <linux/tcp.h>
 110#include <linux/init.h>
 111#include <linux/highmem.h>
 112#include <linux/user_namespace.h>
 113#include <linux/static_key.h>
 114#include <linux/memcontrol.h>
 115#include <linux/prefetch.h>
 116#include <linux/compat.h>
 117
 118#include <linux/uaccess.h>
 119
 120#include <linux/netdevice.h>
 121#include <net/protocol.h>
 122#include <linux/skbuff.h>
 123#include <net/net_namespace.h>
 124#include <net/request_sock.h>
 125#include <net/sock.h>
 126#include <linux/net_tstamp.h>
 127#include <net/xfrm.h>
 128#include <linux/ipsec.h>
 129#include <net/cls_cgroup.h>
 130#include <net/netprio_cgroup.h>
 131#include <linux/sock_diag.h>
 132
 133#include <linux/filter.h>
 134#include <net/sock_reuseport.h>
 135#include <net/bpf_sk_storage.h>
 136
 137#include <trace/events/sock.h>
 138
 
 139#include <net/tcp.h>
 
 
 140#include <net/busy_poll.h>
 141
 142static DEFINE_MUTEX(proto_list_mutex);
 143static LIST_HEAD(proto_list);
 144
 145static void sock_inuse_add(struct net *net, int val);
 146
 147/**
 148 * sk_ns_capable - General socket capability test
 149 * @sk: Socket to use a capability on or through
 150 * @user_ns: The user namespace of the capability to use
 151 * @cap: The capability to use
 152 *
 153 * Test to see if the opener of the socket had when the socket was
 154 * created and the current process has the capability @cap in the user
 155 * namespace @user_ns.
 156 */
 157bool sk_ns_capable(const struct sock *sk,
 158		   struct user_namespace *user_ns, int cap)
 159{
 160	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
 161		ns_capable(user_ns, cap);
 162}
 163EXPORT_SYMBOL(sk_ns_capable);
 164
 165/**
 166 * sk_capable - Socket global capability test
 167 * @sk: Socket to use a capability on or through
 168 * @cap: The global capability to use
 169 *
 170 * Test to see if the opener of the socket had when the socket was
 171 * created and the current process has the capability @cap in all user
 172 * namespaces.
 173 */
 174bool sk_capable(const struct sock *sk, int cap)
 175{
 176	return sk_ns_capable(sk, &init_user_ns, cap);
 177}
 178EXPORT_SYMBOL(sk_capable);
 179
 180/**
 181 * sk_net_capable - Network namespace socket capability test
 182 * @sk: Socket to use a capability on or through
 183 * @cap: The capability to use
 184 *
 185 * Test to see if the opener of the socket had when the socket was created
 186 * and the current process has the capability @cap over the network namespace
 187 * the socket is a member of.
 188 */
 189bool sk_net_capable(const struct sock *sk, int cap)
 190{
 191	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
 192}
 193EXPORT_SYMBOL(sk_net_capable);
 194
 195/*
 196 * Each address family might have different locking rules, so we have
 197 * one slock key per address family and separate keys for internal and
 198 * userspace sockets.
 199 */
 200static struct lock_class_key af_family_keys[AF_MAX];
 201static struct lock_class_key af_family_kern_keys[AF_MAX];
 202static struct lock_class_key af_family_slock_keys[AF_MAX];
 203static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
 204
 205/*
 206 * Make lock validator output more readable. (we pre-construct these
 207 * strings build-time, so that runtime initialization of socket
 208 * locks is fast):
 209 */
 210
 211#define _sock_locks(x)						  \
 212  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
 213  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
 214  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
 215  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
 216  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
 217  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
 218  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
 219  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
 220  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
 221  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
 222  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
 223  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
 224  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
 225  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
 226  x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
 227  x "AF_MAX"
 228
 229static const char *const af_family_key_strings[AF_MAX+1] = {
 230	_sock_locks("sk_lock-")
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 231};
 232static const char *const af_family_slock_key_strings[AF_MAX+1] = {
 233	_sock_locks("slock-")
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 234};
 235static const char *const af_family_clock_key_strings[AF_MAX+1] = {
 236	_sock_locks("clock-")
 237};
 238
 239static const char *const af_family_kern_key_strings[AF_MAX+1] = {
 240	_sock_locks("k-sk_lock-")
 241};
 242static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
 243	_sock_locks("k-slock-")
 244};
 245static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
 246	_sock_locks("k-clock-")
 247};
 248static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
 249	_sock_locks("rlock-")
 250};
 251static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
 252	_sock_locks("wlock-")
 253};
 254static const char *const af_family_elock_key_strings[AF_MAX+1] = {
 255	_sock_locks("elock-")
 256};
 257
 258/*
 259 * sk_callback_lock and sk queues locking rules are per-address-family,
 260 * so split the lock classes by using a per-AF key:
 261 */
 262static struct lock_class_key af_callback_keys[AF_MAX];
 263static struct lock_class_key af_rlock_keys[AF_MAX];
 264static struct lock_class_key af_wlock_keys[AF_MAX];
 265static struct lock_class_key af_elock_keys[AF_MAX];
 266static struct lock_class_key af_kern_callback_keys[AF_MAX];
 
 
 
 
 
 
 267
 268/* Run time adjustable parameters. */
 269__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 270EXPORT_SYMBOL(sysctl_wmem_max);
 271__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 272EXPORT_SYMBOL(sysctl_rmem_max);
 273__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 274__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 275
 276/* Maximal space eaten by iovec or ancillary data plus some space */
 277int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
 278EXPORT_SYMBOL(sysctl_optmem_max);
 279
 280int sysctl_tstamp_allow_data __read_mostly = 1;
 281
 282DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
 283EXPORT_SYMBOL_GPL(memalloc_socks_key);
 284
 285/**
 286 * sk_set_memalloc - sets %SOCK_MEMALLOC
 287 * @sk: socket to set it on
 288 *
 289 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 290 * It's the responsibility of the admin to adjust min_free_kbytes
 291 * to meet the requirements
 292 */
 293void sk_set_memalloc(struct sock *sk)
 294{
 295	sock_set_flag(sk, SOCK_MEMALLOC);
 296	sk->sk_allocation |= __GFP_MEMALLOC;
 297	static_branch_inc(&memalloc_socks_key);
 298}
 299EXPORT_SYMBOL_GPL(sk_set_memalloc);
 300
 301void sk_clear_memalloc(struct sock *sk)
 302{
 303	sock_reset_flag(sk, SOCK_MEMALLOC);
 304	sk->sk_allocation &= ~__GFP_MEMALLOC;
 305	static_branch_dec(&memalloc_socks_key);
 306
 307	/*
 308	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 309	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 310	 * it has rmem allocations due to the last swapfile being deactivated
 311	 * but there is a risk that the socket is unusable due to exceeding
 312	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 313	 */
 314	sk_mem_reclaim(sk);
 315}
 316EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 317
 318int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 319{
 320	int ret;
 321	unsigned int noreclaim_flag;
 322
 323	/* these should have been dropped before queueing */
 324	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 325
 326	noreclaim_flag = memalloc_noreclaim_save();
 327	ret = sk->sk_backlog_rcv(sk, skb);
 328	memalloc_noreclaim_restore(noreclaim_flag);
 329
 330	return ret;
 331}
 332EXPORT_SYMBOL(__sk_backlog_rcv);
 333
 334static int sock_get_timeout(long timeo, void *optval, bool old_timeval)
 335{
 336	struct __kernel_sock_timeval tv;
 337
 338	if (timeo == MAX_SCHEDULE_TIMEOUT) {
 339		tv.tv_sec = 0;
 340		tv.tv_usec = 0;
 341	} else {
 342		tv.tv_sec = timeo / HZ;
 343		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
 344	}
 345
 346	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 347		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
 348		*(struct old_timeval32 *)optval = tv32;
 349		return sizeof(tv32);
 350	}
 351
 352	if (old_timeval) {
 353		struct __kernel_old_timeval old_tv;
 354		old_tv.tv_sec = tv.tv_sec;
 355		old_tv.tv_usec = tv.tv_usec;
 356		*(struct __kernel_old_timeval *)optval = old_tv;
 357		return sizeof(old_tv);
 358	}
 359
 360	*(struct __kernel_sock_timeval *)optval = tv;
 361	return sizeof(tv);
 362}
 363
 364static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
 365			    bool old_timeval)
 366{
 367	struct __kernel_sock_timeval tv;
 368
 369	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
 370		struct old_timeval32 tv32;
 371
 372		if (optlen < sizeof(tv32))
 373			return -EINVAL;
 374
 375		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
 376			return -EFAULT;
 377		tv.tv_sec = tv32.tv_sec;
 378		tv.tv_usec = tv32.tv_usec;
 379	} else if (old_timeval) {
 380		struct __kernel_old_timeval old_tv;
 381
 382		if (optlen < sizeof(old_tv))
 383			return -EINVAL;
 384		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
 385			return -EFAULT;
 386		tv.tv_sec = old_tv.tv_sec;
 387		tv.tv_usec = old_tv.tv_usec;
 388	} else {
 389		if (optlen < sizeof(tv))
 390			return -EINVAL;
 391		if (copy_from_sockptr(&tv, optval, sizeof(tv)))
 392			return -EFAULT;
 393	}
 394	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 395		return -EDOM;
 396
 397	if (tv.tv_sec < 0) {
 398		static int warned __read_mostly;
 399
 400		*timeo_p = 0;
 401		if (warned < 10 && net_ratelimit()) {
 402			warned++;
 403			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 404				__func__, current->comm, task_pid_nr(current));
 405		}
 406		return 0;
 407	}
 408	*timeo_p = MAX_SCHEDULE_TIMEOUT;
 409	if (tv.tv_sec == 0 && tv.tv_usec == 0)
 410		return 0;
 411	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
 412		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
 413	return 0;
 414}
 415
 416static void sock_warn_obsolete_bsdism(const char *name)
 417{
 418	static int warned;
 419	static char warncomm[TASK_COMM_LEN];
 420	if (strcmp(warncomm, current->comm) && warned < 5) {
 421		strcpy(warncomm,  current->comm);
 422		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
 423			warncomm, name);
 424		warned++;
 425	}
 426}
 427
 428static bool sock_needs_netstamp(const struct sock *sk)
 429{
 430	switch (sk->sk_family) {
 431	case AF_UNSPEC:
 432	case AF_UNIX:
 433		return false;
 434	default:
 435		return true;
 436	}
 437}
 438
 439static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 440{
 441	if (sk->sk_flags & flags) {
 442		sk->sk_flags &= ~flags;
 443		if (sock_needs_netstamp(sk) &&
 444		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 445			net_disable_timestamp();
 446	}
 447}
 448
 449
 450int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 451{
 
 452	unsigned long flags;
 453	struct sk_buff_head *list = &sk->sk_receive_queue;
 454
 455	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
 456		atomic_inc(&sk->sk_drops);
 457		trace_sock_rcvqueue_full(sk, skb);
 458		return -ENOMEM;
 459	}
 460
 
 
 
 
 461	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 462		atomic_inc(&sk->sk_drops);
 463		return -ENOBUFS;
 464	}
 465
 466	skb->dev = NULL;
 467	skb_set_owner_r(skb, sk);
 468
 469	/* we escape from rcu protected region, make sure we dont leak
 470	 * a norefcounted dst
 471	 */
 472	skb_dst_force(skb);
 473
 474	spin_lock_irqsave(&list->lock, flags);
 475	sock_skb_set_dropcount(sk, skb);
 476	__skb_queue_tail(list, skb);
 477	spin_unlock_irqrestore(&list->lock, flags);
 478
 479	if (!sock_flag(sk, SOCK_DEAD))
 480		sk->sk_data_ready(sk);
 481	return 0;
 482}
 483EXPORT_SYMBOL(__sock_queue_rcv_skb);
 484
 485int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 486{
 487	int err;
 488
 489	err = sk_filter(sk, skb);
 490	if (err)
 491		return err;
 492
 493	return __sock_queue_rcv_skb(sk, skb);
 494}
 495EXPORT_SYMBOL(sock_queue_rcv_skb);
 496
 497int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
 498		     const int nested, unsigned int trim_cap, bool refcounted)
 499{
 500	int rc = NET_RX_SUCCESS;
 501
 502	if (sk_filter_trim_cap(sk, skb, trim_cap))
 503		goto discard_and_relse;
 504
 505	skb->dev = NULL;
 506
 507	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 508		atomic_inc(&sk->sk_drops);
 509		goto discard_and_relse;
 510	}
 511	if (nested)
 512		bh_lock_sock_nested(sk);
 513	else
 514		bh_lock_sock(sk);
 515	if (!sock_owned_by_user(sk)) {
 516		/*
 517		 * trylock + unlock semantics:
 518		 */
 519		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 520
 521		rc = sk_backlog_rcv(sk, skb);
 522
 523		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
 524	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
 525		bh_unlock_sock(sk);
 526		atomic_inc(&sk->sk_drops);
 527		goto discard_and_relse;
 528	}
 529
 530	bh_unlock_sock(sk);
 531out:
 532	if (refcounted)
 533		sock_put(sk);
 534	return rc;
 535discard_and_relse:
 536	kfree_skb(skb);
 537	goto out;
 538}
 539EXPORT_SYMBOL(__sk_receive_skb);
 540
 541struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 542{
 543	struct dst_entry *dst = __sk_dst_get(sk);
 544
 545	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 546		sk_tx_queue_clear(sk);
 547		sk->sk_dst_pending_confirm = 0;
 548		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 549		dst_release(dst);
 550		return NULL;
 551	}
 552
 553	return dst;
 554}
 555EXPORT_SYMBOL(__sk_dst_check);
 556
 557struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 558{
 559	struct dst_entry *dst = sk_dst_get(sk);
 560
 561	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 562		sk_dst_reset(sk);
 563		dst_release(dst);
 564		return NULL;
 565	}
 566
 567	return dst;
 568}
 569EXPORT_SYMBOL(sk_dst_check);
 570
 571static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
 
 572{
 573	int ret = -ENOPROTOOPT;
 574#ifdef CONFIG_NETDEVICES
 575	struct net *net = sock_net(sk);
 
 
 576
 577	/* Sorry... */
 578	ret = -EPERM;
 579	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
 580		goto out;
 581
 582	ret = -EINVAL;
 583	if (ifindex < 0)
 584		goto out;
 585
 586	sk->sk_bound_dev_if = ifindex;
 587	if (sk->sk_prot->rehash)
 588		sk->sk_prot->rehash(sk);
 589	sk_dst_reset(sk);
 590
 591	ret = 0;
 592
 593out:
 594#endif
 595
 596	return ret;
 597}
 598
 599int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
 600{
 601	int ret;
 602
 603	if (lock_sk)
 604		lock_sock(sk);
 605	ret = sock_bindtoindex_locked(sk, ifindex);
 606	if (lock_sk)
 607		release_sock(sk);
 608
 609	return ret;
 610}
 611EXPORT_SYMBOL(sock_bindtoindex);
 612
 613static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
 614{
 615	int ret = -ENOPROTOOPT;
 616#ifdef CONFIG_NETDEVICES
 617	struct net *net = sock_net(sk);
 618	char devname[IFNAMSIZ];
 619	int index;
 620
 621	ret = -EINVAL;
 622	if (optlen < 0)
 623		goto out;
 624
 625	/* Bind this socket to a particular device like "eth0",
 626	 * as specified in the passed interface name. If the
 627	 * name is "" or the option length is zero the socket
 628	 * is not bound.
 629	 */
 630	if (optlen > IFNAMSIZ - 1)
 631		optlen = IFNAMSIZ - 1;
 632	memset(devname, 0, sizeof(devname));
 633
 634	ret = -EFAULT;
 635	if (copy_from_sockptr(devname, optval, optlen))
 636		goto out;
 637
 638	index = 0;
 639	if (devname[0] != '\0') {
 640		struct net_device *dev;
 641
 642		rcu_read_lock();
 643		dev = dev_get_by_name_rcu(net, devname);
 644		if (dev)
 645			index = dev->ifindex;
 646		rcu_read_unlock();
 647		ret = -ENODEV;
 648		if (!dev)
 649			goto out;
 650	}
 651
 652	return sock_bindtoindex(sk, index, true);
 
 
 
 
 
 
 653out:
 654#endif
 655
 656	return ret;
 657}
 658
 659static int sock_getbindtodevice(struct sock *sk, char __user *optval,
 660				int __user *optlen, int len)
 661{
 662	int ret = -ENOPROTOOPT;
 663#ifdef CONFIG_NETDEVICES
 664	struct net *net = sock_net(sk);
 665	char devname[IFNAMSIZ];
 666
 667	if (sk->sk_bound_dev_if == 0) {
 668		len = 0;
 669		goto zero;
 670	}
 671
 672	ret = -EINVAL;
 673	if (len < IFNAMSIZ)
 674		goto out;
 675
 676	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
 677	if (ret)
 678		goto out;
 679
 680	len = strlen(devname) + 1;
 681
 682	ret = -EFAULT;
 683	if (copy_to_user(optval, devname, len))
 684		goto out;
 685
 686zero:
 687	ret = -EFAULT;
 688	if (put_user(len, optlen))
 689		goto out;
 690
 691	ret = 0;
 692
 693out:
 694#endif
 695
 696	return ret;
 697}
 698
 
 
 
 
 
 
 
 
 699bool sk_mc_loop(struct sock *sk)
 700{
 701	if (dev_recursion_level())
 702		return false;
 703	if (!sk)
 704		return true;
 705	switch (sk->sk_family) {
 706	case AF_INET:
 707		return inet_sk(sk)->mc_loop;
 708#if IS_ENABLED(CONFIG_IPV6)
 709	case AF_INET6:
 710		return inet6_sk(sk)->mc_loop;
 711#endif
 712	}
 713	WARN_ON_ONCE(1);
 714	return true;
 715}
 716EXPORT_SYMBOL(sk_mc_loop);
 717
 718void sock_set_reuseaddr(struct sock *sk)
 719{
 720	lock_sock(sk);
 721	sk->sk_reuse = SK_CAN_REUSE;
 722	release_sock(sk);
 723}
 724EXPORT_SYMBOL(sock_set_reuseaddr);
 725
 726void sock_set_reuseport(struct sock *sk)
 727{
 728	lock_sock(sk);
 729	sk->sk_reuseport = true;
 730	release_sock(sk);
 731}
 732EXPORT_SYMBOL(sock_set_reuseport);
 733
 734void sock_no_linger(struct sock *sk)
 735{
 736	lock_sock(sk);
 737	sk->sk_lingertime = 0;
 738	sock_set_flag(sk, SOCK_LINGER);
 739	release_sock(sk);
 740}
 741EXPORT_SYMBOL(sock_no_linger);
 742
 743void sock_set_priority(struct sock *sk, u32 priority)
 744{
 745	lock_sock(sk);
 746	sk->sk_priority = priority;
 747	release_sock(sk);
 748}
 749EXPORT_SYMBOL(sock_set_priority);
 750
 751void sock_set_sndtimeo(struct sock *sk, s64 secs)
 752{
 753	lock_sock(sk);
 754	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
 755		sk->sk_sndtimeo = secs * HZ;
 756	else
 757		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
 758	release_sock(sk);
 759}
 760EXPORT_SYMBOL(sock_set_sndtimeo);
 761
 762static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
 763{
 764	if (val)  {
 765		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
 766		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
 767		sock_set_flag(sk, SOCK_RCVTSTAMP);
 768		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 769	} else {
 770		sock_reset_flag(sk, SOCK_RCVTSTAMP);
 771		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 772		sock_reset_flag(sk, SOCK_TSTAMP_NEW);
 773	}
 774}
 775
 776void sock_enable_timestamps(struct sock *sk)
 777{
 778	lock_sock(sk);
 779	__sock_set_timestamps(sk, true, false, true);
 780	release_sock(sk);
 781}
 782EXPORT_SYMBOL(sock_enable_timestamps);
 783
 784void sock_set_keepalive(struct sock *sk)
 785{
 786	lock_sock(sk);
 787	if (sk->sk_prot->keepalive)
 788		sk->sk_prot->keepalive(sk, true);
 789	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
 790	release_sock(sk);
 791}
 792EXPORT_SYMBOL(sock_set_keepalive);
 793
 794static void __sock_set_rcvbuf(struct sock *sk, int val)
 795{
 796	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
 797	 * as a negative value.
 798	 */
 799	val = min_t(int, val, INT_MAX / 2);
 800	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 801
 802	/* We double it on the way in to account for "struct sk_buff" etc.
 803	 * overhead.   Applications assume that the SO_RCVBUF setting they make
 804	 * will allow that much actual data to be received on that socket.
 805	 *
 806	 * Applications are unaware that "struct sk_buff" and other overheads
 807	 * allocate from the receive buffer during socket buffer allocation.
 808	 *
 809	 * And after considering the possible alternatives, returning the value
 810	 * we actually used in getsockopt is the most desirable behavior.
 811	 */
 812	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
 813}
 814
 815void sock_set_rcvbuf(struct sock *sk, int val)
 816{
 817	lock_sock(sk);
 818	__sock_set_rcvbuf(sk, val);
 819	release_sock(sk);
 820}
 821EXPORT_SYMBOL(sock_set_rcvbuf);
 822
 823void sock_set_mark(struct sock *sk, u32 val)
 824{
 825	lock_sock(sk);
 826	sk->sk_mark = val;
 827	release_sock(sk);
 828}
 829EXPORT_SYMBOL(sock_set_mark);
 830
 831/*
 832 *	This is meant for all protocols to use and covers goings on
 833 *	at the socket level. Everything here is generic.
 834 */
 835
 836int sock_setsockopt(struct socket *sock, int level, int optname,
 837		    sockptr_t optval, unsigned int optlen)
 838{
 839	struct sock_txtime sk_txtime;
 840	struct sock *sk = sock->sk;
 841	int val;
 842	int valbool;
 843	struct linger ling;
 844	int ret = 0;
 845
 846	/*
 847	 *	Options without arguments
 848	 */
 849
 850	if (optname == SO_BINDTODEVICE)
 851		return sock_setbindtodevice(sk, optval, optlen);
 852
 853	if (optlen < sizeof(int))
 854		return -EINVAL;
 855
 856	if (copy_from_sockptr(&val, optval, sizeof(val)))
 857		return -EFAULT;
 858
 859	valbool = val ? 1 : 0;
 860
 861	lock_sock(sk);
 862
 863	switch (optname) {
 864	case SO_DEBUG:
 865		if (val && !capable(CAP_NET_ADMIN))
 866			ret = -EACCES;
 867		else
 868			sock_valbool_flag(sk, SOCK_DBG, valbool);
 869		break;
 870	case SO_REUSEADDR:
 871		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
 872		break;
 873	case SO_REUSEPORT:
 874		sk->sk_reuseport = valbool;
 875		break;
 876	case SO_TYPE:
 877	case SO_PROTOCOL:
 878	case SO_DOMAIN:
 879	case SO_ERROR:
 880		ret = -ENOPROTOOPT;
 881		break;
 882	case SO_DONTROUTE:
 883		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
 884		sk_dst_reset(sk);
 885		break;
 886	case SO_BROADCAST:
 887		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
 888		break;
 889	case SO_SNDBUF:
 890		/* Don't error on this BSD doesn't and if you think
 891		 * about it this is right. Otherwise apps have to
 892		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
 893		 * are treated in BSD as hints
 894		 */
 895		val = min_t(u32, val, sysctl_wmem_max);
 896set_sndbuf:
 897		/* Ensure val * 2 fits into an int, to prevent max_t()
 898		 * from treating it as a negative value.
 899		 */
 900		val = min_t(int, val, INT_MAX / 2);
 901		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
 902		WRITE_ONCE(sk->sk_sndbuf,
 903			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
 904		/* Wake up sending tasks if we upped the value. */
 905		sk->sk_write_space(sk);
 906		break;
 907
 908	case SO_SNDBUFFORCE:
 909		if (!capable(CAP_NET_ADMIN)) {
 910			ret = -EPERM;
 911			break;
 912		}
 913
 914		/* No negative values (to prevent underflow, as val will be
 915		 * multiplied by 2).
 916		 */
 917		if (val < 0)
 918			val = 0;
 919		goto set_sndbuf;
 920
 921	case SO_RCVBUF:
 922		/* Don't error on this BSD doesn't and if you think
 923		 * about it this is right. Otherwise apps have to
 924		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
 925		 * are treated in BSD as hints
 926		 */
 927		__sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 928		break;
 929
 930	case SO_RCVBUFFORCE:
 931		if (!capable(CAP_NET_ADMIN)) {
 932			ret = -EPERM;
 933			break;
 934		}
 935
 936		/* No negative values (to prevent underflow, as val will be
 937		 * multiplied by 2).
 938		 */
 939		__sock_set_rcvbuf(sk, max(val, 0));
 940		break;
 941
 942	case SO_KEEPALIVE:
 943		if (sk->sk_prot->keepalive)
 944			sk->sk_prot->keepalive(sk, valbool);
 
 
 
 945		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
 946		break;
 947
 948	case SO_OOBINLINE:
 949		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
 950		break;
 951
 952	case SO_NO_CHECK:
 953		sk->sk_no_check_tx = valbool;
 954		break;
 955
 956	case SO_PRIORITY:
 957		if ((val >= 0 && val <= 6) ||
 958		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 959			sk->sk_priority = val;
 960		else
 961			ret = -EPERM;
 962		break;
 963
 964	case SO_LINGER:
 965		if (optlen < sizeof(ling)) {
 966			ret = -EINVAL;	/* 1003.1g */
 967			break;
 968		}
 969		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
 970			ret = -EFAULT;
 971			break;
 972		}
 973		if (!ling.l_onoff)
 974			sock_reset_flag(sk, SOCK_LINGER);
 975		else {
 976#if (BITS_PER_LONG == 32)
 977			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
 978				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
 979			else
 980#endif
 981				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
 982			sock_set_flag(sk, SOCK_LINGER);
 983		}
 984		break;
 985
 986	case SO_BSDCOMPAT:
 987		sock_warn_obsolete_bsdism("setsockopt");
 988		break;
 989
 990	case SO_PASSCRED:
 991		if (valbool)
 992			set_bit(SOCK_PASSCRED, &sock->flags);
 993		else
 994			clear_bit(SOCK_PASSCRED, &sock->flags);
 995		break;
 996
 997	case SO_TIMESTAMP_OLD:
 998		__sock_set_timestamps(sk, valbool, false, false);
 999		break;
1000	case SO_TIMESTAMP_NEW:
1001		__sock_set_timestamps(sk, valbool, true, false);
1002		break;
1003	case SO_TIMESTAMPNS_OLD:
1004		__sock_set_timestamps(sk, valbool, false, true);
 
 
 
 
 
1005		break;
1006	case SO_TIMESTAMPNS_NEW:
1007		__sock_set_timestamps(sk, valbool, true, true);
1008		break;
1009	case SO_TIMESTAMPING_NEW:
1010		sock_set_flag(sk, SOCK_TSTAMP_NEW);
1011		fallthrough;
1012	case SO_TIMESTAMPING_OLD:
1013		if (val & ~SOF_TIMESTAMPING_MASK) {
1014			ret = -EINVAL;
1015			break;
1016		}
1017
1018		if (val & SOF_TIMESTAMPING_OPT_ID &&
1019		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
1020			if (sk->sk_protocol == IPPROTO_TCP &&
1021			    sk->sk_type == SOCK_STREAM) {
1022				if ((1 << sk->sk_state) &
1023				    (TCPF_CLOSE | TCPF_LISTEN)) {
1024					ret = -EINVAL;
1025					break;
1026				}
1027				sk->sk_tskey = tcp_sk(sk)->snd_una;
1028			} else {
1029				sk->sk_tskey = 0;
1030			}
1031		}
1032
1033		if (val & SOF_TIMESTAMPING_OPT_STATS &&
1034		    !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
1035			ret = -EINVAL;
1036			break;
1037		}
1038
1039		sk->sk_tsflags = val;
1040		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
1041			sock_enable_timestamp(sk,
1042					      SOCK_TIMESTAMPING_RX_SOFTWARE);
1043		else {
1044			if (optname == SO_TIMESTAMPING_NEW)
1045				sock_reset_flag(sk, SOCK_TSTAMP_NEW);
1046
1047			sock_disable_timestamp(sk,
1048					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
1049		}
1050		break;
1051
1052	case SO_RCVLOWAT:
1053		if (val < 0)
1054			val = INT_MAX;
1055		if (sock->ops->set_rcvlowat)
1056			ret = sock->ops->set_rcvlowat(sk, val);
1057		else
1058			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1059		break;
1060
1061	case SO_RCVTIMEO_OLD:
1062	case SO_RCVTIMEO_NEW:
1063		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1064				       optlen, optname == SO_RCVTIMEO_OLD);
1065		break;
1066
1067	case SO_SNDTIMEO_OLD:
1068	case SO_SNDTIMEO_NEW:
1069		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1070				       optlen, optname == SO_SNDTIMEO_OLD);
1071		break;
1072
1073	case SO_ATTACH_FILTER: {
1074		struct sock_fprog fprog;
 
 
 
 
 
 
1075
1076		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1077		if (!ret)
1078			ret = sk_attach_filter(&fprog, sk);
 
1079		break;
1080	}
1081	case SO_ATTACH_BPF:
1082		ret = -EINVAL;
1083		if (optlen == sizeof(u32)) {
1084			u32 ufd;
1085
1086			ret = -EFAULT;
1087			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1088				break;
1089
1090			ret = sk_attach_bpf(ufd, sk);
1091		}
1092		break;
1093
1094	case SO_ATTACH_REUSEPORT_CBPF: {
1095		struct sock_fprog fprog;
 
 
 
 
 
 
1096
1097		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1098		if (!ret)
1099			ret = sk_reuseport_attach_filter(&fprog, sk);
 
1100		break;
1101	}
1102	case SO_ATTACH_REUSEPORT_EBPF:
1103		ret = -EINVAL;
1104		if (optlen == sizeof(u32)) {
1105			u32 ufd;
1106
1107			ret = -EFAULT;
1108			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1109				break;
1110
1111			ret = sk_reuseport_attach_bpf(ufd, sk);
1112		}
1113		break;
1114
1115	case SO_DETACH_REUSEPORT_BPF:
1116		ret = reuseport_detach_prog(sk);
1117		break;
1118
1119	case SO_DETACH_FILTER:
1120		ret = sk_detach_filter(sk);
1121		break;
1122
1123	case SO_LOCK_FILTER:
1124		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1125			ret = -EPERM;
1126		else
1127			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1128		break;
1129
1130	case SO_PASSSEC:
1131		if (valbool)
1132			set_bit(SOCK_PASSSEC, &sock->flags);
1133		else
1134			clear_bit(SOCK_PASSSEC, &sock->flags);
1135		break;
1136	case SO_MARK:
1137		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1138			ret = -EPERM;
1139		} else if (val != sk->sk_mark) {
1140			sk->sk_mark = val;
1141			sk_dst_reset(sk);
1142		}
1143		break;
1144
1145	case SO_RXQ_OVFL:
1146		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1147		break;
1148
1149	case SO_WIFI_STATUS:
1150		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1151		break;
1152
1153	case SO_PEEK_OFF:
1154		if (sock->ops->set_peek_off)
1155			ret = sock->ops->set_peek_off(sk, val);
1156		else
1157			ret = -EOPNOTSUPP;
1158		break;
1159
1160	case SO_NOFCS:
1161		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1162		break;
1163
1164	case SO_SELECT_ERR_QUEUE:
1165		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1166		break;
1167
1168#ifdef CONFIG_NET_RX_BUSY_POLL
1169	case SO_BUSY_POLL:
1170		/* allow unprivileged users to decrease the value */
1171		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1172			ret = -EPERM;
1173		else {
1174			if (val < 0)
1175				ret = -EINVAL;
1176			else
1177				sk->sk_ll_usec = val;
1178		}
1179		break;
1180#endif
1181
1182	case SO_MAX_PACING_RATE:
1183		{
1184		unsigned long ulval = (val == ~0U) ? ~0UL : val;
1185
1186		if (sizeof(ulval) != sizeof(val) &&
1187		    optlen >= sizeof(ulval) &&
1188		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1189			ret = -EFAULT;
1190			break;
1191		}
1192		if (ulval != ~0UL)
1193			cmpxchg(&sk->sk_pacing_status,
1194				SK_PACING_NONE,
1195				SK_PACING_NEEDED);
1196		sk->sk_max_pacing_rate = ulval;
1197		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1198		break;
1199		}
1200	case SO_INCOMING_CPU:
1201		WRITE_ONCE(sk->sk_incoming_cpu, val);
1202		break;
1203
1204	case SO_CNX_ADVICE:
1205		if (val == 1)
1206			dst_negative_advice(sk);
1207		break;
1208
1209	case SO_ZEROCOPY:
1210		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1211			if (!((sk->sk_type == SOCK_STREAM &&
1212			       sk->sk_protocol == IPPROTO_TCP) ||
1213			      (sk->sk_type == SOCK_DGRAM &&
1214			       sk->sk_protocol == IPPROTO_UDP)))
1215				ret = -ENOTSUPP;
1216		} else if (sk->sk_family != PF_RDS) {
1217			ret = -ENOTSUPP;
1218		}
1219		if (!ret) {
1220			if (val < 0 || val > 1)
1221				ret = -EINVAL;
1222			else
1223				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1224		}
1225		break;
1226
1227	case SO_TXTIME:
1228		if (optlen != sizeof(struct sock_txtime)) {
1229			ret = -EINVAL;
1230			break;
1231		} else if (copy_from_sockptr(&sk_txtime, optval,
1232			   sizeof(struct sock_txtime))) {
1233			ret = -EFAULT;
1234			break;
1235		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1236			ret = -EINVAL;
1237			break;
1238		}
1239		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1240		 * scheduler has enough safe guards.
1241		 */
1242		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1243		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1244			ret = -EPERM;
1245			break;
1246		}
1247		sock_valbool_flag(sk, SOCK_TXTIME, true);
1248		sk->sk_clockid = sk_txtime.clockid;
1249		sk->sk_txtime_deadline_mode =
1250			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1251		sk->sk_txtime_report_errors =
1252			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1253		break;
1254
1255	case SO_BINDTOIFINDEX:
1256		ret = sock_bindtoindex_locked(sk, val);
1257		break;
1258
1259	default:
1260		ret = -ENOPROTOOPT;
1261		break;
1262	}
1263	release_sock(sk);
1264	return ret;
1265}
1266EXPORT_SYMBOL(sock_setsockopt);
1267
1268
1269static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1270			  struct ucred *ucred)
1271{
1272	ucred->pid = pid_vnr(pid);
1273	ucred->uid = ucred->gid = -1;
1274	if (cred) {
1275		struct user_namespace *current_ns = current_user_ns();
1276
1277		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1278		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1279	}
1280}
1281
1282static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1283{
1284	struct user_namespace *user_ns = current_user_ns();
1285	int i;
1286
1287	for (i = 0; i < src->ngroups; i++)
1288		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1289			return -EFAULT;
1290
1291	return 0;
1292}
1293
1294int sock_getsockopt(struct socket *sock, int level, int optname,
1295		    char __user *optval, int __user *optlen)
1296{
1297	struct sock *sk = sock->sk;
1298
1299	union {
1300		int val;
1301		u64 val64;
1302		unsigned long ulval;
1303		struct linger ling;
1304		struct old_timeval32 tm32;
1305		struct __kernel_old_timeval tm;
1306		struct  __kernel_sock_timeval stm;
1307		struct sock_txtime txtime;
1308	} v;
1309
1310	int lv = sizeof(int);
1311	int len;
1312
1313	if (get_user(len, optlen))
1314		return -EFAULT;
1315	if (len < 0)
1316		return -EINVAL;
1317
1318	memset(&v, 0, sizeof(v));
1319
1320	switch (optname) {
1321	case SO_DEBUG:
1322		v.val = sock_flag(sk, SOCK_DBG);
1323		break;
1324
1325	case SO_DONTROUTE:
1326		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1327		break;
1328
1329	case SO_BROADCAST:
1330		v.val = sock_flag(sk, SOCK_BROADCAST);
1331		break;
1332
1333	case SO_SNDBUF:
1334		v.val = sk->sk_sndbuf;
1335		break;
1336
1337	case SO_RCVBUF:
1338		v.val = sk->sk_rcvbuf;
1339		break;
1340
1341	case SO_REUSEADDR:
1342		v.val = sk->sk_reuse;
1343		break;
1344
1345	case SO_REUSEPORT:
1346		v.val = sk->sk_reuseport;
1347		break;
1348
1349	case SO_KEEPALIVE:
1350		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1351		break;
1352
1353	case SO_TYPE:
1354		v.val = sk->sk_type;
1355		break;
1356
1357	case SO_PROTOCOL:
1358		v.val = sk->sk_protocol;
1359		break;
1360
1361	case SO_DOMAIN:
1362		v.val = sk->sk_family;
1363		break;
1364
1365	case SO_ERROR:
1366		v.val = -sock_error(sk);
1367		if (v.val == 0)
1368			v.val = xchg(&sk->sk_err_soft, 0);
1369		break;
1370
1371	case SO_OOBINLINE:
1372		v.val = sock_flag(sk, SOCK_URGINLINE);
1373		break;
1374
1375	case SO_NO_CHECK:
1376		v.val = sk->sk_no_check_tx;
1377		break;
1378
1379	case SO_PRIORITY:
1380		v.val = sk->sk_priority;
1381		break;
1382
1383	case SO_LINGER:
1384		lv		= sizeof(v.ling);
1385		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1386		v.ling.l_linger	= sk->sk_lingertime / HZ;
1387		break;
1388
1389	case SO_BSDCOMPAT:
1390		sock_warn_obsolete_bsdism("getsockopt");
1391		break;
1392
1393	case SO_TIMESTAMP_OLD:
1394		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1395				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1396				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1397		break;
1398
1399	case SO_TIMESTAMPNS_OLD:
1400		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1401		break;
1402
1403	case SO_TIMESTAMP_NEW:
1404		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1405		break;
1406
1407	case SO_TIMESTAMPNS_NEW:
1408		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1409		break;
1410
1411	case SO_TIMESTAMPING_OLD:
1412		v.val = sk->sk_tsflags;
1413		break;
1414
1415	case SO_RCVTIMEO_OLD:
1416	case SO_RCVTIMEO_NEW:
1417		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
 
 
 
 
 
 
1418		break;
1419
1420	case SO_SNDTIMEO_OLD:
1421	case SO_SNDTIMEO_NEW:
1422		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
 
 
 
 
 
 
1423		break;
1424
1425	case SO_RCVLOWAT:
1426		v.val = sk->sk_rcvlowat;
1427		break;
1428
1429	case SO_SNDLOWAT:
1430		v.val = 1;
1431		break;
1432
1433	case SO_PASSCRED:
1434		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1435		break;
1436
1437	case SO_PEERCRED:
1438	{
1439		struct ucred peercred;
1440		if (len > sizeof(peercred))
1441			len = sizeof(peercred);
1442		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1443		if (copy_to_user(optval, &peercred, len))
1444			return -EFAULT;
1445		goto lenout;
1446	}
1447
1448	case SO_PEERGROUPS:
1449	{
1450		int ret, n;
1451
1452		if (!sk->sk_peer_cred)
1453			return -ENODATA;
1454
1455		n = sk->sk_peer_cred->group_info->ngroups;
1456		if (len < n * sizeof(gid_t)) {
1457			len = n * sizeof(gid_t);
1458			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1459		}
1460		len = n * sizeof(gid_t);
1461
1462		ret = groups_to_user((gid_t __user *)optval,
1463				     sk->sk_peer_cred->group_info);
1464		if (ret)
1465			return ret;
1466		goto lenout;
1467	}
1468
1469	case SO_PEERNAME:
1470	{
1471		char address[128];
1472
1473		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1474		if (lv < 0)
1475			return -ENOTCONN;
1476		if (lv < len)
1477			return -EINVAL;
1478		if (copy_to_user(optval, address, len))
1479			return -EFAULT;
1480		goto lenout;
1481	}
1482
1483	/* Dubious BSD thing... Probably nobody even uses it, but
1484	 * the UNIX standard wants it for whatever reason... -DaveM
1485	 */
1486	case SO_ACCEPTCONN:
1487		v.val = sk->sk_state == TCP_LISTEN;
1488		break;
1489
1490	case SO_PASSSEC:
1491		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1492		break;
1493
1494	case SO_PEERSEC:
1495		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1496
1497	case SO_MARK:
1498		v.val = sk->sk_mark;
1499		break;
1500
1501	case SO_RXQ_OVFL:
1502		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1503		break;
1504
1505	case SO_WIFI_STATUS:
1506		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1507		break;
1508
1509	case SO_PEEK_OFF:
1510		if (!sock->ops->set_peek_off)
1511			return -EOPNOTSUPP;
1512
1513		v.val = sk->sk_peek_off;
1514		break;
1515	case SO_NOFCS:
1516		v.val = sock_flag(sk, SOCK_NOFCS);
1517		break;
1518
1519	case SO_BINDTODEVICE:
1520		return sock_getbindtodevice(sk, optval, optlen, len);
1521
1522	case SO_GET_FILTER:
1523		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1524		if (len < 0)
1525			return len;
1526
1527		goto lenout;
1528
1529	case SO_LOCK_FILTER:
1530		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1531		break;
1532
1533	case SO_BPF_EXTENSIONS:
1534		v.val = bpf_tell_extensions();
1535		break;
1536
1537	case SO_SELECT_ERR_QUEUE:
1538		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1539		break;
1540
1541#ifdef CONFIG_NET_RX_BUSY_POLL
1542	case SO_BUSY_POLL:
1543		v.val = sk->sk_ll_usec;
1544		break;
1545#endif
1546
1547	case SO_MAX_PACING_RATE:
1548		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1549			lv = sizeof(v.ulval);
1550			v.ulval = sk->sk_max_pacing_rate;
1551		} else {
1552			/* 32bit version */
1553			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1554		}
1555		break;
1556
1557	case SO_INCOMING_CPU:
1558		v.val = READ_ONCE(sk->sk_incoming_cpu);
1559		break;
1560
1561	case SO_MEMINFO:
1562	{
1563		u32 meminfo[SK_MEMINFO_VARS];
1564
1565		sk_get_meminfo(sk, meminfo);
1566
1567		len = min_t(unsigned int, len, sizeof(meminfo));
1568		if (copy_to_user(optval, &meminfo, len))
1569			return -EFAULT;
1570
1571		goto lenout;
1572	}
1573
1574#ifdef CONFIG_NET_RX_BUSY_POLL
1575	case SO_INCOMING_NAPI_ID:
1576		v.val = READ_ONCE(sk->sk_napi_id);
1577
1578		/* aggregate non-NAPI IDs down to 0 */
1579		if (v.val < MIN_NAPI_ID)
1580			v.val = 0;
1581
1582		break;
1583#endif
1584
1585	case SO_COOKIE:
1586		lv = sizeof(u64);
1587		if (len < lv)
1588			return -EINVAL;
1589		v.val64 = sock_gen_cookie(sk);
1590		break;
1591
1592	case SO_ZEROCOPY:
1593		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1594		break;
1595
1596	case SO_TXTIME:
1597		lv = sizeof(v.txtime);
1598		v.txtime.clockid = sk->sk_clockid;
1599		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1600				  SOF_TXTIME_DEADLINE_MODE : 0;
1601		v.txtime.flags |= sk->sk_txtime_report_errors ?
1602				  SOF_TXTIME_REPORT_ERRORS : 0;
1603		break;
1604
1605	case SO_BINDTOIFINDEX:
1606		v.val = sk->sk_bound_dev_if;
1607		break;
1608
1609	default:
1610		/* We implement the SO_SNDLOWAT etc to not be settable
1611		 * (1003.1g 7).
1612		 */
1613		return -ENOPROTOOPT;
1614	}
1615
1616	if (len > lv)
1617		len = lv;
1618	if (copy_to_user(optval, &v, len))
1619		return -EFAULT;
1620lenout:
1621	if (put_user(len, optlen))
1622		return -EFAULT;
1623	return 0;
1624}
1625
1626/*
1627 * Initialize an sk_lock.
1628 *
1629 * (We also register the sk_lock with the lock validator.)
1630 */
1631static inline void sock_lock_init(struct sock *sk)
1632{
1633	if (sk->sk_kern_sock)
1634		sock_lock_init_class_and_name(
1635			sk,
1636			af_family_kern_slock_key_strings[sk->sk_family],
1637			af_family_kern_slock_keys + sk->sk_family,
1638			af_family_kern_key_strings[sk->sk_family],
1639			af_family_kern_keys + sk->sk_family);
1640	else
1641		sock_lock_init_class_and_name(
1642			sk,
1643			af_family_slock_key_strings[sk->sk_family],
1644			af_family_slock_keys + sk->sk_family,
1645			af_family_key_strings[sk->sk_family],
1646			af_family_keys + sk->sk_family);
1647}
1648
1649/*
1650 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1651 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1652 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1653 */
1654static void sock_copy(struct sock *nsk, const struct sock *osk)
1655{
1656	const struct proto *prot = READ_ONCE(osk->sk_prot);
1657#ifdef CONFIG_SECURITY_NETWORK
1658	void *sptr = nsk->sk_security;
1659#endif
1660	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1661
1662	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1663	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1664
1665#ifdef CONFIG_SECURITY_NETWORK
1666	nsk->sk_security = sptr;
1667	security_sk_clone(osk, nsk);
1668#endif
1669}
1670
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1671static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1672		int family)
1673{
1674	struct sock *sk;
1675	struct kmem_cache *slab;
1676
1677	slab = prot->slab;
1678	if (slab != NULL) {
1679		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1680		if (!sk)
1681			return sk;
1682		if (want_init_on_alloc(priority))
1683			sk_prot_clear_nulls(sk, prot->obj_size);
 
 
 
 
1684	} else
1685		sk = kmalloc(prot->obj_size, priority);
1686
1687	if (sk != NULL) {
 
 
1688		if (security_sk_alloc(sk, family, priority))
1689			goto out_free;
1690
1691		if (!try_module_get(prot->owner))
1692			goto out_free_sec;
1693		sk_tx_queue_clear(sk);
 
1694	}
1695
1696	return sk;
1697
1698out_free_sec:
1699	security_sk_free(sk);
1700out_free:
1701	if (slab != NULL)
1702		kmem_cache_free(slab, sk);
1703	else
1704		kfree(sk);
1705	return NULL;
1706}
1707
1708static void sk_prot_free(struct proto *prot, struct sock *sk)
1709{
1710	struct kmem_cache *slab;
1711	struct module *owner;
1712
1713	owner = prot->owner;
1714	slab = prot->slab;
1715
1716	cgroup_sk_free(&sk->sk_cgrp_data);
1717	mem_cgroup_sk_free(sk);
1718	security_sk_free(sk);
1719	if (slab != NULL)
1720		kmem_cache_free(slab, sk);
1721	else
1722		kfree(sk);
1723	module_put(owner);
1724}
1725
1726/**
1727 *	sk_alloc - All socket objects are allocated here
1728 *	@net: the applicable net namespace
1729 *	@family: protocol family
1730 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1731 *	@prot: struct proto associated with this new sock instance
1732 *	@kern: is this to be a kernel socket?
1733 */
1734struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1735		      struct proto *prot, int kern)
1736{
1737	struct sock *sk;
1738
1739	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1740	if (sk) {
1741		sk->sk_family = family;
1742		/*
1743		 * See comment in struct sock definition to understand
1744		 * why we need sk_prot_creator -acme
1745		 */
1746		sk->sk_prot = sk->sk_prot_creator = prot;
1747		sk->sk_kern_sock = kern;
1748		sock_lock_init(sk);
1749		sk->sk_net_refcnt = kern ? 0 : 1;
1750		if (likely(sk->sk_net_refcnt)) {
1751			get_net(net);
1752			sock_inuse_add(net, 1);
1753		}
1754
1755		sock_net_set(sk, net);
1756		refcount_set(&sk->sk_wmem_alloc, 1);
1757
1758		mem_cgroup_sk_alloc(sk);
1759		cgroup_sk_alloc(&sk->sk_cgrp_data);
1760		sock_update_classid(&sk->sk_cgrp_data);
1761		sock_update_netprioidx(&sk->sk_cgrp_data);
1762		sk_tx_queue_clear(sk);
1763	}
1764
1765	return sk;
1766}
1767EXPORT_SYMBOL(sk_alloc);
1768
1769/* Sockets having SOCK_RCU_FREE will call this function after one RCU
1770 * grace period. This is the case for UDP sockets and TCP listeners.
1771 */
1772static void __sk_destruct(struct rcu_head *head)
1773{
1774	struct sock *sk = container_of(head, struct sock, sk_rcu);
1775	struct sk_filter *filter;
1776
1777	if (sk->sk_destruct)
1778		sk->sk_destruct(sk);
1779
1780	filter = rcu_dereference_check(sk->sk_filter,
1781				       refcount_read(&sk->sk_wmem_alloc) == 0);
1782	if (filter) {
1783		sk_filter_uncharge(sk, filter);
1784		RCU_INIT_POINTER(sk->sk_filter, NULL);
1785	}
 
 
1786
1787	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1788
1789#ifdef CONFIG_BPF_SYSCALL
1790	bpf_sk_storage_free(sk);
1791#endif
1792
1793	if (atomic_read(&sk->sk_omem_alloc))
1794		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1795			 __func__, atomic_read(&sk->sk_omem_alloc));
1796
1797	if (sk->sk_frag.page) {
1798		put_page(sk->sk_frag.page);
1799		sk->sk_frag.page = NULL;
1800	}
1801
1802	if (sk->sk_peer_cred)
1803		put_cred(sk->sk_peer_cred);
1804	put_pid(sk->sk_peer_pid);
1805	if (likely(sk->sk_net_refcnt))
1806		put_net(sock_net(sk));
1807	sk_prot_free(sk->sk_prot_creator, sk);
1808}
1809
1810void sk_destruct(struct sock *sk)
1811{
1812	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
1813
1814	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
1815		reuseport_detach_sock(sk);
1816		use_call_rcu = true;
1817	}
1818
1819	if (use_call_rcu)
1820		call_rcu(&sk->sk_rcu, __sk_destruct);
1821	else
1822		__sk_destruct(&sk->sk_rcu);
1823}
1824
1825static void __sk_free(struct sock *sk)
1826{
1827	if (likely(sk->sk_net_refcnt))
1828		sock_inuse_add(sock_net(sk), -1);
1829
1830	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1831		sock_diag_broadcast_destroy(sk);
1832	else
1833		sk_destruct(sk);
1834}
1835
1836void sk_free(struct sock *sk)
1837{
1838	/*
1839	 * We subtract one from sk_wmem_alloc and can know if
1840	 * some packets are still in some tx queue.
1841	 * If not null, sock_wfree() will call __sk_free(sk) later
1842	 */
1843	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1844		__sk_free(sk);
1845}
1846EXPORT_SYMBOL(sk_free);
1847
1848static void sk_init_common(struct sock *sk)
1849{
1850	skb_queue_head_init(&sk->sk_receive_queue);
1851	skb_queue_head_init(&sk->sk_write_queue);
1852	skb_queue_head_init(&sk->sk_error_queue);
1853
1854	rwlock_init(&sk->sk_callback_lock);
1855	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1856			af_rlock_keys + sk->sk_family,
1857			af_family_rlock_key_strings[sk->sk_family]);
1858	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1859			af_wlock_keys + sk->sk_family,
1860			af_family_wlock_key_strings[sk->sk_family]);
1861	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1862			af_elock_keys + sk->sk_family,
1863			af_family_elock_key_strings[sk->sk_family]);
1864	lockdep_set_class_and_name(&sk->sk_callback_lock,
1865			af_callback_keys + sk->sk_family,
1866			af_family_clock_key_strings[sk->sk_family]);
1867}
1868
1869/**
1870 *	sk_clone_lock - clone a socket, and lock its clone
1871 *	@sk: the socket to clone
1872 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1873 *
1874 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1875 */
1876struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1877{
1878	struct proto *prot = READ_ONCE(sk->sk_prot);
1879	struct sock *newsk;
1880	bool is_charged = true;
1881
1882	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
1883	if (newsk != NULL) {
1884		struct sk_filter *filter;
1885
1886		sock_copy(newsk, sk);
1887
1888		newsk->sk_prot_creator = prot;
1889
1890		/* SANITY */
1891		if (likely(newsk->sk_net_refcnt))
1892			get_net(sock_net(newsk));
1893		sk_node_init(&newsk->sk_node);
1894		sock_lock_init(newsk);
1895		bh_lock_sock(newsk);
1896		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1897		newsk->sk_backlog.len = 0;
1898
1899		atomic_set(&newsk->sk_rmem_alloc, 0);
1900		/*
1901		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1902		 */
1903		refcount_set(&newsk->sk_wmem_alloc, 1);
1904		atomic_set(&newsk->sk_omem_alloc, 0);
1905		sk_init_common(newsk);
 
 
 
 
 
 
1906
1907		newsk->sk_dst_cache	= NULL;
1908		newsk->sk_dst_pending_confirm = 0;
1909		newsk->sk_wmem_queued	= 0;
1910		newsk->sk_forward_alloc = 0;
1911		atomic_set(&newsk->sk_drops, 0);
1912		newsk->sk_send_head	= NULL;
1913		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1914		atomic_set(&newsk->sk_zckey, 0);
1915
1916		sock_reset_flag(newsk, SOCK_DONE);
 
1917
1918		/* sk->sk_memcg will be populated at accept() time */
1919		newsk->sk_memcg = NULL;
1920
1921		cgroup_sk_clone(&newsk->sk_cgrp_data);
1922
1923		rcu_read_lock();
1924		filter = rcu_dereference(sk->sk_filter);
1925		if (filter != NULL)
1926			/* though it's an empty new sock, the charging may fail
1927			 * if sysctl_optmem_max was changed between creation of
1928			 * original socket and cloning
1929			 */
1930			is_charged = sk_filter_charge(newsk, filter);
1931		RCU_INIT_POINTER(newsk->sk_filter, filter);
1932		rcu_read_unlock();
1933
1934		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1935			/* We need to make sure that we don't uncharge the new
1936			 * socket if we couldn't charge it in the first place
1937			 * as otherwise we uncharge the parent's filter.
1938			 */
1939			if (!is_charged)
1940				RCU_INIT_POINTER(newsk->sk_filter, NULL);
1941			sk_free_unlock_clone(newsk);
1942			newsk = NULL;
1943			goto out;
1944		}
1945		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1946
1947		if (bpf_sk_storage_clone(sk, newsk)) {
1948			sk_free_unlock_clone(newsk);
1949			newsk = NULL;
1950			goto out;
1951		}
1952
1953		/* Clear sk_user_data if parent had the pointer tagged
1954		 * as not suitable for copying when cloning.
1955		 */
1956		if (sk_user_data_is_nocopy(newsk))
1957			newsk->sk_user_data = NULL;
1958
1959		newsk->sk_err	   = 0;
1960		newsk->sk_err_soft = 0;
1961		newsk->sk_priority = 0;
1962		newsk->sk_incoming_cpu = raw_smp_processor_id();
1963		if (likely(newsk->sk_net_refcnt))
1964			sock_inuse_add(sock_net(newsk), 1);
1965
1966		/*
1967		 * Before updating sk_refcnt, we must commit prior changes to memory
1968		 * (Documentation/RCU/rculist_nulls.rst for details)
1969		 */
1970		smp_wmb();
1971		refcount_set(&newsk->sk_refcnt, 2);
1972
1973		/*
1974		 * Increment the counter in the same struct proto as the master
1975		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1976		 * is the same as sk->sk_prot->socks, as this field was copied
1977		 * with memcpy).
1978		 *
1979		 * This _changes_ the previous behaviour, where
1980		 * tcp_create_openreq_child always was incrementing the
1981		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1982		 * to be taken into account in all callers. -acme
1983		 */
1984		sk_refcnt_debug_inc(newsk);
1985		sk_set_socket(newsk, NULL);
1986		sk_tx_queue_clear(newsk);
1987		RCU_INIT_POINTER(newsk->sk_wq, NULL);
 
 
1988
1989		if (newsk->sk_prot->sockets_allocated)
1990			sk_sockets_allocated_inc(newsk);
1991
1992		if (sock_needs_netstamp(sk) &&
1993		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1994			net_enable_timestamp();
1995	}
1996out:
1997	return newsk;
1998}
1999EXPORT_SYMBOL_GPL(sk_clone_lock);
2000
2001void sk_free_unlock_clone(struct sock *sk)
2002{
2003	/* It is still raw copy of parent, so invalidate
2004	 * destructor and make plain sk_free() */
2005	sk->sk_destruct = NULL;
2006	bh_unlock_sock(sk);
2007	sk_free(sk);
2008}
2009EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2010
2011void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2012{
2013	u32 max_segs = 1;
2014
2015	sk_dst_set(sk, dst);
2016	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
2017	if (sk->sk_route_caps & NETIF_F_GSO)
2018		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2019	sk->sk_route_caps &= ~sk->sk_route_nocaps;
2020	if (sk_can_gso(sk)) {
2021		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2022			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2023		} else {
2024			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2025			sk->sk_gso_max_size = dst->dev->gso_max_size;
2026			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
2027		}
2028	}
2029	sk->sk_gso_max_segs = max_segs;
2030}
2031EXPORT_SYMBOL_GPL(sk_setup_caps);
2032
2033/*
2034 *	Simple resource managers for sockets.
2035 */
2036
2037
2038/*
2039 * Write buffer destructor automatically called from kfree_skb.
2040 */
2041void sock_wfree(struct sk_buff *skb)
2042{
2043	struct sock *sk = skb->sk;
2044	unsigned int len = skb->truesize;
2045
2046	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2047		/*
2048		 * Keep a reference on sk_wmem_alloc, this will be released
2049		 * after sk_write_space() call
2050		 */
2051		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2052		sk->sk_write_space(sk);
2053		len = 1;
2054	}
2055	/*
2056	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2057	 * could not do because of in-flight packets
2058	 */
2059	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2060		__sk_free(sk);
2061}
2062EXPORT_SYMBOL(sock_wfree);
2063
2064/* This variant of sock_wfree() is used by TCP,
2065 * since it sets SOCK_USE_WRITE_QUEUE.
2066 */
2067void __sock_wfree(struct sk_buff *skb)
2068{
2069	struct sock *sk = skb->sk;
2070
2071	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2072		__sk_free(sk);
2073}
2074
2075void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2076{
2077	skb_orphan(skb);
2078	skb->sk = sk;
2079#ifdef CONFIG_INET
2080	if (unlikely(!sk_fullsock(sk))) {
2081		skb->destructor = sock_edemux;
2082		sock_hold(sk);
2083		return;
2084	}
2085#endif
2086	skb->destructor = sock_wfree;
2087	skb_set_hash_from_sk(skb, sk);
2088	/*
2089	 * We used to take a refcount on sk, but following operation
2090	 * is enough to guarantee sk_free() wont free this sock until
2091	 * all in-flight packets are completed
2092	 */
2093	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2094}
2095EXPORT_SYMBOL(skb_set_owner_w);
2096
2097static bool can_skb_orphan_partial(const struct sk_buff *skb)
2098{
2099#ifdef CONFIG_TLS_DEVICE
2100	/* Drivers depend on in-order delivery for crypto offload,
2101	 * partial orphan breaks out-of-order-OK logic.
2102	 */
2103	if (skb->decrypted)
2104		return false;
 
2105#endif
2106	return (skb->destructor == sock_wfree ||
2107		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2108}
2109
2110/* This helper is used by netem, as it can hold packets in its
2111 * delay queue. We want to allow the owner socket to send more
2112 * packets, as if they were already TX completed by a typical driver.
2113 * But we also want to keep skb->sk set because some packet schedulers
2114 * rely on it (sch_fq for example).
2115 */
2116void skb_orphan_partial(struct sk_buff *skb)
2117{
2118	if (skb_is_tcp_pure_ack(skb))
2119		return;
2120
2121	if (can_skb_orphan_partial(skb)) {
2122		struct sock *sk = skb->sk;
2123
2124		if (refcount_inc_not_zero(&sk->sk_refcnt)) {
2125			WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
2126			skb->destructor = sock_efree;
2127		}
2128	} else {
2129		skb_orphan(skb);
2130	}
2131}
2132EXPORT_SYMBOL(skb_orphan_partial);
2133
2134/*
2135 * Read buffer destructor automatically called from kfree_skb.
2136 */
2137void sock_rfree(struct sk_buff *skb)
2138{
2139	struct sock *sk = skb->sk;
2140	unsigned int len = skb->truesize;
2141
2142	atomic_sub(len, &sk->sk_rmem_alloc);
2143	sk_mem_uncharge(sk, len);
2144}
2145EXPORT_SYMBOL(sock_rfree);
2146
2147/*
2148 * Buffer destructor for skbs that are not used directly in read or write
2149 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2150 */
2151void sock_efree(struct sk_buff *skb)
2152{
2153	sock_put(skb->sk);
2154}
2155EXPORT_SYMBOL(sock_efree);
2156
2157/* Buffer destructor for prefetch/receive path where reference count may
2158 * not be held, e.g. for listen sockets.
2159 */
2160#ifdef CONFIG_INET
2161void sock_pfree(struct sk_buff *skb)
2162{
2163	if (sk_is_refcounted(skb->sk))
2164		sock_gen_put(skb->sk);
2165}
2166EXPORT_SYMBOL(sock_pfree);
2167#endif /* CONFIG_INET */
2168
2169kuid_t sock_i_uid(struct sock *sk)
2170{
2171	kuid_t uid;
2172
2173	read_lock_bh(&sk->sk_callback_lock);
2174	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2175	read_unlock_bh(&sk->sk_callback_lock);
2176	return uid;
2177}
2178EXPORT_SYMBOL(sock_i_uid);
2179
2180unsigned long sock_i_ino(struct sock *sk)
2181{
2182	unsigned long ino;
2183
2184	read_lock_bh(&sk->sk_callback_lock);
2185	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2186	read_unlock_bh(&sk->sk_callback_lock);
2187	return ino;
2188}
2189EXPORT_SYMBOL(sock_i_ino);
2190
2191/*
2192 * Allocate a skb from the socket's send buffer.
2193 */
2194struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2195			     gfp_t priority)
2196{
2197	if (force ||
2198	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2199		struct sk_buff *skb = alloc_skb(size, priority);
2200
2201		if (skb) {
2202			skb_set_owner_w(skb, sk);
2203			return skb;
2204		}
2205	}
2206	return NULL;
2207}
2208EXPORT_SYMBOL(sock_wmalloc);
2209
2210static void sock_ofree(struct sk_buff *skb)
2211{
2212	struct sock *sk = skb->sk;
2213
2214	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2215}
2216
2217struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2218			     gfp_t priority)
2219{
2220	struct sk_buff *skb;
2221
2222	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2223	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2224	    sysctl_optmem_max)
2225		return NULL;
2226
2227	skb = alloc_skb(size, priority);
2228	if (!skb)
2229		return NULL;
2230
2231	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2232	skb->sk = sk;
2233	skb->destructor = sock_ofree;
2234	return skb;
2235}
2236
2237/*
2238 * Allocate a memory block from the socket's option memory buffer.
2239 */
2240void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2241{
2242	if ((unsigned int)size <= sysctl_optmem_max &&
2243	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2244		void *mem;
2245		/* First do the add, to avoid the race if kmalloc
2246		 * might sleep.
2247		 */
2248		atomic_add(size, &sk->sk_omem_alloc);
2249		mem = kmalloc(size, priority);
2250		if (mem)
2251			return mem;
2252		atomic_sub(size, &sk->sk_omem_alloc);
2253	}
2254	return NULL;
2255}
2256EXPORT_SYMBOL(sock_kmalloc);
2257
2258/* Free an option memory block. Note, we actually want the inline
2259 * here as this allows gcc to detect the nullify and fold away the
2260 * condition entirely.
2261 */
2262static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2263				  const bool nullify)
2264{
2265	if (WARN_ON_ONCE(!mem))
2266		return;
2267	if (nullify)
2268		kfree_sensitive(mem);
2269	else
2270		kfree(mem);
2271	atomic_sub(size, &sk->sk_omem_alloc);
2272}
2273
2274void sock_kfree_s(struct sock *sk, void *mem, int size)
2275{
2276	__sock_kfree_s(sk, mem, size, false);
2277}
2278EXPORT_SYMBOL(sock_kfree_s);
2279
2280void sock_kzfree_s(struct sock *sk, void *mem, int size)
2281{
2282	__sock_kfree_s(sk, mem, size, true);
2283}
2284EXPORT_SYMBOL(sock_kzfree_s);
2285
2286/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2287   I think, these locks should be removed for datagram sockets.
2288 */
2289static long sock_wait_for_wmem(struct sock *sk, long timeo)
2290{
2291	DEFINE_WAIT(wait);
2292
2293	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2294	for (;;) {
2295		if (!timeo)
2296			break;
2297		if (signal_pending(current))
2298			break;
2299		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2300		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2301		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2302			break;
2303		if (sk->sk_shutdown & SEND_SHUTDOWN)
2304			break;
2305		if (sk->sk_err)
2306			break;
2307		timeo = schedule_timeout(timeo);
2308	}
2309	finish_wait(sk_sleep(sk), &wait);
2310	return timeo;
2311}
2312
2313
2314/*
2315 *	Generic send/receive buffer handlers
2316 */
2317
2318struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2319				     unsigned long data_len, int noblock,
2320				     int *errcode, int max_page_order)
2321{
2322	struct sk_buff *skb;
2323	long timeo;
2324	int err;
2325
2326	timeo = sock_sndtimeo(sk, noblock);
2327	for (;;) {
2328		err = sock_error(sk);
2329		if (err != 0)
2330			goto failure;
2331
2332		err = -EPIPE;
2333		if (sk->sk_shutdown & SEND_SHUTDOWN)
2334			goto failure;
2335
2336		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2337			break;
2338
2339		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2340		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2341		err = -EAGAIN;
2342		if (!timeo)
2343			goto failure;
2344		if (signal_pending(current))
2345			goto interrupted;
2346		timeo = sock_wait_for_wmem(sk, timeo);
2347	}
2348	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2349				   errcode, sk->sk_allocation);
2350	if (skb)
2351		skb_set_owner_w(skb, sk);
2352	return skb;
2353
2354interrupted:
2355	err = sock_intr_errno(timeo);
2356failure:
2357	*errcode = err;
2358	return NULL;
2359}
2360EXPORT_SYMBOL(sock_alloc_send_pskb);
2361
2362struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2363				    int noblock, int *errcode)
2364{
2365	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2366}
2367EXPORT_SYMBOL(sock_alloc_send_skb);
2368
2369int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2370		     struct sockcm_cookie *sockc)
2371{
2372	u32 tsflags;
2373
2374	switch (cmsg->cmsg_type) {
2375	case SO_MARK:
2376		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2377			return -EPERM;
2378		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2379			return -EINVAL;
2380		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2381		break;
2382	case SO_TIMESTAMPING_OLD:
2383		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2384			return -EINVAL;
2385
2386		tsflags = *(u32 *)CMSG_DATA(cmsg);
2387		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2388			return -EINVAL;
2389
2390		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2391		sockc->tsflags |= tsflags;
2392		break;
2393	case SCM_TXTIME:
2394		if (!sock_flag(sk, SOCK_TXTIME))
2395			return -EINVAL;
2396		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2397			return -EINVAL;
2398		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2399		break;
2400	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2401	case SCM_RIGHTS:
2402	case SCM_CREDENTIALS:
2403		break;
2404	default:
2405		return -EINVAL;
2406	}
2407	return 0;
2408}
2409EXPORT_SYMBOL(__sock_cmsg_send);
2410
2411int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2412		   struct sockcm_cookie *sockc)
2413{
2414	struct cmsghdr *cmsg;
2415	int ret;
2416
2417	for_each_cmsghdr(cmsg, msg) {
2418		if (!CMSG_OK(msg, cmsg))
2419			return -EINVAL;
2420		if (cmsg->cmsg_level != SOL_SOCKET)
2421			continue;
2422		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2423		if (ret)
2424			return ret;
 
 
 
 
 
 
 
 
2425	}
2426	return 0;
2427}
2428EXPORT_SYMBOL(sock_cmsg_send);
2429
2430static void sk_enter_memory_pressure(struct sock *sk)
2431{
2432	if (!sk->sk_prot->enter_memory_pressure)
2433		return;
2434
2435	sk->sk_prot->enter_memory_pressure(sk);
2436}
2437
2438static void sk_leave_memory_pressure(struct sock *sk)
2439{
2440	if (sk->sk_prot->leave_memory_pressure) {
2441		sk->sk_prot->leave_memory_pressure(sk);
2442	} else {
2443		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2444
2445		if (memory_pressure && READ_ONCE(*memory_pressure))
2446			WRITE_ONCE(*memory_pressure, 0);
2447	}
2448}
2449
2450#define SKB_FRAG_PAGE_ORDER	get_order(32768)
2451DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2452
2453/**
2454 * skb_page_frag_refill - check that a page_frag contains enough room
2455 * @sz: minimum size of the fragment we want to get
2456 * @pfrag: pointer to page_frag
2457 * @gfp: priority for memory allocation
2458 *
2459 * Note: While this allocator tries to use high order pages, there is
2460 * no guarantee that allocations succeed. Therefore, @sz MUST be
2461 * less or equal than PAGE_SIZE.
2462 */
2463bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2464{
2465	if (pfrag->page) {
2466		if (page_ref_count(pfrag->page) == 1) {
2467			pfrag->offset = 0;
2468			return true;
2469		}
2470		if (pfrag->offset + sz <= pfrag->size)
2471			return true;
2472		put_page(pfrag->page);
2473	}
2474
2475	pfrag->offset = 0;
2476	if (SKB_FRAG_PAGE_ORDER &&
2477	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2478		/* Avoid direct reclaim but allow kswapd to wake */
2479		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2480					  __GFP_COMP | __GFP_NOWARN |
2481					  __GFP_NORETRY,
2482					  SKB_FRAG_PAGE_ORDER);
2483		if (likely(pfrag->page)) {
2484			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2485			return true;
2486		}
2487	}
2488	pfrag->page = alloc_page(gfp);
2489	if (likely(pfrag->page)) {
2490		pfrag->size = PAGE_SIZE;
2491		return true;
2492	}
2493	return false;
2494}
2495EXPORT_SYMBOL(skb_page_frag_refill);
2496
2497bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2498{
2499	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2500		return true;
2501
2502	sk_enter_memory_pressure(sk);
2503	sk_stream_moderate_sndbuf(sk);
2504	return false;
2505}
2506EXPORT_SYMBOL(sk_page_frag_refill);
2507
2508static void __lock_sock(struct sock *sk)
2509	__releases(&sk->sk_lock.slock)
2510	__acquires(&sk->sk_lock.slock)
2511{
2512	DEFINE_WAIT(wait);
2513
2514	for (;;) {
2515		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2516					TASK_UNINTERRUPTIBLE);
2517		spin_unlock_bh(&sk->sk_lock.slock);
2518		schedule();
2519		spin_lock_bh(&sk->sk_lock.slock);
2520		if (!sock_owned_by_user(sk))
2521			break;
2522	}
2523	finish_wait(&sk->sk_lock.wq, &wait);
2524}
2525
2526void __release_sock(struct sock *sk)
2527	__releases(&sk->sk_lock.slock)
2528	__acquires(&sk->sk_lock.slock)
2529{
2530	struct sk_buff *skb, *next;
2531
2532	while ((skb = sk->sk_backlog.head) != NULL) {
2533		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2534
2535		spin_unlock_bh(&sk->sk_lock.slock);
2536
2537		do {
2538			next = skb->next;
 
2539			prefetch(next);
2540			WARN_ON_ONCE(skb_dst_is_noref(skb));
2541			skb_mark_not_on_list(skb);
2542			sk_backlog_rcv(sk, skb);
2543
2544			cond_resched();
 
 
 
 
 
 
2545
2546			skb = next;
2547		} while (skb != NULL);
2548
2549		spin_lock_bh(&sk->sk_lock.slock);
2550	}
2551
2552	/*
2553	 * Doing the zeroing here guarantee we can not loop forever
2554	 * while a wild producer attempts to flood us.
2555	 */
2556	sk->sk_backlog.len = 0;
2557}
2558
2559void __sk_flush_backlog(struct sock *sk)
2560{
2561	spin_lock_bh(&sk->sk_lock.slock);
2562	__release_sock(sk);
2563	spin_unlock_bh(&sk->sk_lock.slock);
2564}
2565
2566/**
2567 * sk_wait_data - wait for data to arrive at sk_receive_queue
2568 * @sk:    sock to wait on
2569 * @timeo: for how long
2570 * @skb:   last skb seen on sk_receive_queue
2571 *
2572 * Now socket state including sk->sk_err is changed only under lock,
2573 * hence we may omit checks after joining wait queue.
2574 * We check receive queue before schedule() only as optimization;
2575 * it is very likely that release_sock() added new data.
2576 */
2577int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2578{
2579	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2580	int rc;
 
2581
2582	add_wait_queue(sk_sleep(sk), &wait);
2583	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2584	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2585	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2586	remove_wait_queue(sk_sleep(sk), &wait);
2587	return rc;
2588}
2589EXPORT_SYMBOL(sk_wait_data);
2590
2591/**
2592 *	__sk_mem_raise_allocated - increase memory_allocated
2593 *	@sk: socket
2594 *	@size: memory size to allocate
2595 *	@amt: pages to allocate
2596 *	@kind: allocation type
2597 *
2598 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
 
 
2599 */
2600int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2601{
2602	struct proto *prot = sk->sk_prot;
2603	long allocated = sk_memory_allocated_add(sk, amt);
2604	bool charged = true;
 
 
 
 
2605
2606	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2607	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2608		goto suppress_allocation;
2609
2610	/* Under limit. */
2611	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2612		sk_leave_memory_pressure(sk);
2613		return 1;
2614	}
2615
2616	/* Under pressure. */
2617	if (allocated > sk_prot_mem_limits(sk, 1))
2618		sk_enter_memory_pressure(sk);
2619
2620	/* Over hard limit. */
2621	if (allocated > sk_prot_mem_limits(sk, 2))
2622		goto suppress_allocation;
2623
2624	/* guarantee minimum buffer size under pressure */
2625	if (kind == SK_MEM_RECV) {
2626		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2627			return 1;
2628
2629	} else { /* SK_MEM_SEND */
2630		int wmem0 = sk_get_wmem0(sk, prot);
2631
2632		if (sk->sk_type == SOCK_STREAM) {
2633			if (sk->sk_wmem_queued < wmem0)
2634				return 1;
2635		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
 
2636				return 1;
2637		}
2638	}
2639
2640	if (sk_has_memory_pressure(sk)) {
2641		u64 alloc;
2642
2643		if (!sk_under_memory_pressure(sk))
2644			return 1;
2645		alloc = sk_sockets_allocated_read_positive(sk);
2646		if (sk_prot_mem_limits(sk, 2) > alloc *
2647		    sk_mem_pages(sk->sk_wmem_queued +
2648				 atomic_read(&sk->sk_rmem_alloc) +
2649				 sk->sk_forward_alloc))
2650			return 1;
2651	}
2652
2653suppress_allocation:
2654
2655	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2656		sk_stream_moderate_sndbuf(sk);
2657
2658		/* Fail only if socket is _under_ its sndbuf.
2659		 * In this case we cannot block, so that we have to fail.
2660		 */
2661		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2662			return 1;
2663	}
2664
2665	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2666		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
 
 
2667
2668	sk_memory_allocated_sub(sk, amt);
2669
2670	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2671		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2672
2673	return 0;
2674}
2675EXPORT_SYMBOL(__sk_mem_raise_allocated);
2676
2677/**
2678 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2679 *	@sk: socket
2680 *	@size: memory size to allocate
2681 *	@kind: allocation type
2682 *
2683 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2684 *	rmem allocation. This function assumes that protocols which have
2685 *	memory_pressure use sk_wmem_queued as write buffer accounting.
2686 */
2687int __sk_mem_schedule(struct sock *sk, int size, int kind)
2688{
2689	int ret, amt = sk_mem_pages(size);
2690
2691	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2692	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2693	if (!ret)
2694		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2695	return ret;
2696}
2697EXPORT_SYMBOL(__sk_mem_schedule);
2698
2699/**
2700 *	__sk_mem_reduce_allocated - reclaim memory_allocated
2701 *	@sk: socket
2702 *	@amount: number of quanta
2703 *
2704 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2705 */
2706void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2707{
 
2708	sk_memory_allocated_sub(sk, amount);
 
2709
2710	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2711		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2712
2713	if (sk_under_memory_pressure(sk) &&
2714	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2715		sk_leave_memory_pressure(sk);
2716}
2717EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2718
2719/**
2720 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2721 *	@sk: socket
2722 *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2723 */
2724void __sk_mem_reclaim(struct sock *sk, int amount)
2725{
2726	amount >>= SK_MEM_QUANTUM_SHIFT;
2727	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2728	__sk_mem_reduce_allocated(sk, amount);
2729}
2730EXPORT_SYMBOL(__sk_mem_reclaim);
2731
2732int sk_set_peek_off(struct sock *sk, int val)
2733{
2734	sk->sk_peek_off = val;
2735	return 0;
2736}
2737EXPORT_SYMBOL_GPL(sk_set_peek_off);
2738
2739/*
2740 * Set of default routines for initialising struct proto_ops when
2741 * the protocol does not support a particular function. In certain
2742 * cases where it makes no sense for a protocol to have a "do nothing"
2743 * function, some default processing is provided.
2744 */
2745
2746int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2747{
2748	return -EOPNOTSUPP;
2749}
2750EXPORT_SYMBOL(sock_no_bind);
2751
2752int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2753		    int len, int flags)
2754{
2755	return -EOPNOTSUPP;
2756}
2757EXPORT_SYMBOL(sock_no_connect);
2758
2759int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2760{
2761	return -EOPNOTSUPP;
2762}
2763EXPORT_SYMBOL(sock_no_socketpair);
2764
2765int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2766		   bool kern)
2767{
2768	return -EOPNOTSUPP;
2769}
2770EXPORT_SYMBOL(sock_no_accept);
2771
2772int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2773		    int peer)
2774{
2775	return -EOPNOTSUPP;
2776}
2777EXPORT_SYMBOL(sock_no_getname);
2778
 
 
 
 
 
 
2779int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2780{
2781	return -EOPNOTSUPP;
2782}
2783EXPORT_SYMBOL(sock_no_ioctl);
2784
2785int sock_no_listen(struct socket *sock, int backlog)
2786{
2787	return -EOPNOTSUPP;
2788}
2789EXPORT_SYMBOL(sock_no_listen);
2790
2791int sock_no_shutdown(struct socket *sock, int how)
2792{
2793	return -EOPNOTSUPP;
2794}
2795EXPORT_SYMBOL(sock_no_shutdown);
2796
2797int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
 
2798{
2799	return -EOPNOTSUPP;
2800}
2801EXPORT_SYMBOL(sock_no_sendmsg);
2802
2803int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
 
2804{
2805	return -EOPNOTSUPP;
2806}
2807EXPORT_SYMBOL(sock_no_sendmsg_locked);
 
 
 
 
 
 
2808
2809int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2810		    int flags)
2811{
2812	return -EOPNOTSUPP;
2813}
2814EXPORT_SYMBOL(sock_no_recvmsg);
2815
2816int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2817{
2818	/* Mirror missing mmap method error code */
2819	return -ENODEV;
2820}
2821EXPORT_SYMBOL(sock_no_mmap);
2822
2823/*
2824 * When a file is received (via SCM_RIGHTS, etc), we must bump the
2825 * various sock-based usage counts.
2826 */
2827void __receive_sock(struct file *file)
2828{
2829	struct socket *sock;
2830	int error;
2831
2832	/*
2833	 * The resulting value of "error" is ignored here since we only
2834	 * need to take action when the file is a socket and testing
2835	 * "sock" for NULL is sufficient.
2836	 */
2837	sock = sock_from_file(file, &error);
2838	if (sock) {
2839		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
2840		sock_update_classid(&sock->sk->sk_cgrp_data);
2841	}
2842}
2843
2844ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2845{
2846	ssize_t res;
2847	struct msghdr msg = {.msg_flags = flags};
2848	struct kvec iov;
2849	char *kaddr = kmap(page);
2850	iov.iov_base = kaddr + offset;
2851	iov.iov_len = size;
2852	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2853	kunmap(page);
2854	return res;
2855}
2856EXPORT_SYMBOL(sock_no_sendpage);
2857
2858ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2859				int offset, size_t size, int flags)
2860{
2861	ssize_t res;
2862	struct msghdr msg = {.msg_flags = flags};
2863	struct kvec iov;
2864	char *kaddr = kmap(page);
2865
2866	iov.iov_base = kaddr + offset;
2867	iov.iov_len = size;
2868	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2869	kunmap(page);
2870	return res;
2871}
2872EXPORT_SYMBOL(sock_no_sendpage_locked);
2873
2874/*
2875 *	Default Socket Callbacks
2876 */
2877
2878static void sock_def_wakeup(struct sock *sk)
2879{
2880	struct socket_wq *wq;
2881
2882	rcu_read_lock();
2883	wq = rcu_dereference(sk->sk_wq);
2884	if (skwq_has_sleeper(wq))
2885		wake_up_interruptible_all(&wq->wait);
2886	rcu_read_unlock();
2887}
2888
2889static void sock_def_error_report(struct sock *sk)
2890{
2891	struct socket_wq *wq;
2892
2893	rcu_read_lock();
2894	wq = rcu_dereference(sk->sk_wq);
2895	if (skwq_has_sleeper(wq))
2896		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2897	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2898	rcu_read_unlock();
2899}
2900
2901void sock_def_readable(struct sock *sk)
2902{
2903	struct socket_wq *wq;
2904
2905	rcu_read_lock();
2906	wq = rcu_dereference(sk->sk_wq);
2907	if (skwq_has_sleeper(wq))
2908		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2909						EPOLLRDNORM | EPOLLRDBAND);
2910	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2911	rcu_read_unlock();
2912}
2913
2914static void sock_def_write_space(struct sock *sk)
2915{
2916	struct socket_wq *wq;
2917
2918	rcu_read_lock();
2919
2920	/* Do not wake up a writer until he can make "significant"
2921	 * progress.  --DaveM
2922	 */
2923	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) {
2924		wq = rcu_dereference(sk->sk_wq);
2925		if (skwq_has_sleeper(wq))
2926			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2927						EPOLLWRNORM | EPOLLWRBAND);
2928
2929		/* Should agree with poll, otherwise some programs break */
2930		if (sock_writeable(sk))
2931			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2932	}
2933
2934	rcu_read_unlock();
2935}
2936
2937static void sock_def_destruct(struct sock *sk)
2938{
2939}
2940
2941void sk_send_sigurg(struct sock *sk)
2942{
2943	if (sk->sk_socket && sk->sk_socket->file)
2944		if (send_sigurg(&sk->sk_socket->file->f_owner))
2945			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2946}
2947EXPORT_SYMBOL(sk_send_sigurg);
2948
2949void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2950		    unsigned long expires)
2951{
2952	if (!mod_timer(timer, expires))
2953		sock_hold(sk);
2954}
2955EXPORT_SYMBOL(sk_reset_timer);
2956
2957void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2958{
2959	if (del_timer(timer))
2960		__sock_put(sk);
2961}
2962EXPORT_SYMBOL(sk_stop_timer);
2963
2964void sock_init_data(struct socket *sock, struct sock *sk)
2965{
2966	sk_init_common(sk);
 
 
 
2967	sk->sk_send_head	=	NULL;
2968
2969	timer_setup(&sk->sk_timer, NULL, 0);
2970
2971	sk->sk_allocation	=	GFP_KERNEL;
2972	sk->sk_rcvbuf		=	sysctl_rmem_default;
2973	sk->sk_sndbuf		=	sysctl_wmem_default;
2974	sk->sk_state		=	TCP_CLOSE;
2975	sk_set_socket(sk, sock);
2976
2977	sock_set_flag(sk, SOCK_ZAPPED);
2978
2979	if (sock) {
2980		sk->sk_type	=	sock->type;
2981		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
2982		sock->sk	=	sk;
2983		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2984	} else {
2985		RCU_INIT_POINTER(sk->sk_wq, NULL);
2986		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2987	}
2988
2989	rwlock_init(&sk->sk_callback_lock);
2990	if (sk->sk_kern_sock)
2991		lockdep_set_class_and_name(
2992			&sk->sk_callback_lock,
2993			af_kern_callback_keys + sk->sk_family,
2994			af_family_kern_clock_key_strings[sk->sk_family]);
2995	else
2996		lockdep_set_class_and_name(
2997			&sk->sk_callback_lock,
2998			af_callback_keys + sk->sk_family,
2999			af_family_clock_key_strings[sk->sk_family]);
3000
3001	sk->sk_state_change	=	sock_def_wakeup;
3002	sk->sk_data_ready	=	sock_def_readable;
3003	sk->sk_write_space	=	sock_def_write_space;
3004	sk->sk_error_report	=	sock_def_error_report;
3005	sk->sk_destruct		=	sock_def_destruct;
3006
3007	sk->sk_frag.page	=	NULL;
3008	sk->sk_frag.offset	=	0;
3009	sk->sk_peek_off		=	-1;
3010
3011	sk->sk_peer_pid 	=	NULL;
3012	sk->sk_peer_cred	=	NULL;
3013	sk->sk_write_pending	=	0;
3014	sk->sk_rcvlowat		=	1;
3015	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3016	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3017
3018	sk->sk_stamp = SK_DEFAULT_STAMP;
3019#if BITS_PER_LONG==32
3020	seqlock_init(&sk->sk_stamp_seq);
3021#endif
3022	atomic_set(&sk->sk_zckey, 0);
3023
3024#ifdef CONFIG_NET_RX_BUSY_POLL
3025	sk->sk_napi_id		=	0;
3026	sk->sk_ll_usec		=	sysctl_net_busy_read;
3027#endif
3028
3029	sk->sk_max_pacing_rate = ~0UL;
3030	sk->sk_pacing_rate = ~0UL;
3031	WRITE_ONCE(sk->sk_pacing_shift, 10);
3032	sk->sk_incoming_cpu = -1;
3033
3034	sk_rx_queue_clear(sk);
3035	/*
3036	 * Before updating sk_refcnt, we must commit prior changes to memory
3037	 * (Documentation/RCU/rculist_nulls.rst for details)
3038	 */
3039	smp_wmb();
3040	refcount_set(&sk->sk_refcnt, 1);
3041	atomic_set(&sk->sk_drops, 0);
3042}
3043EXPORT_SYMBOL(sock_init_data);
3044
3045void lock_sock_nested(struct sock *sk, int subclass)
3046{
3047	might_sleep();
3048	spin_lock_bh(&sk->sk_lock.slock);
3049	if (sk->sk_lock.owned)
3050		__lock_sock(sk);
3051	sk->sk_lock.owned = 1;
3052	spin_unlock(&sk->sk_lock.slock);
3053	/*
3054	 * The sk_lock has mutex_lock() semantics here:
3055	 */
3056	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3057	local_bh_enable();
3058}
3059EXPORT_SYMBOL(lock_sock_nested);
3060
3061void release_sock(struct sock *sk)
3062{
 
 
 
 
 
3063	spin_lock_bh(&sk->sk_lock.slock);
3064	if (sk->sk_backlog.tail)
3065		__release_sock(sk);
3066
3067	/* Warning : release_cb() might need to release sk ownership,
3068	 * ie call sock_release_ownership(sk) before us.
3069	 */
3070	if (sk->sk_prot->release_cb)
3071		sk->sk_prot->release_cb(sk);
3072
3073	sock_release_ownership(sk);
3074	if (waitqueue_active(&sk->sk_lock.wq))
3075		wake_up(&sk->sk_lock.wq);
3076	spin_unlock_bh(&sk->sk_lock.slock);
3077}
3078EXPORT_SYMBOL(release_sock);
3079
3080/**
3081 * lock_sock_fast - fast version of lock_sock
3082 * @sk: socket
3083 *
3084 * This version should be used for very small section, where process wont block
3085 * return false if fast path is taken:
3086 *
3087 *   sk_lock.slock locked, owned = 0, BH disabled
3088 *
3089 * return true if slow path is taken:
3090 *
3091 *   sk_lock.slock unlocked, owned = 1, BH enabled
3092 */
3093bool lock_sock_fast(struct sock *sk)
3094{
3095	might_sleep();
3096	spin_lock_bh(&sk->sk_lock.slock);
3097
3098	if (!sk->sk_lock.owned)
3099		/*
3100		 * Note : We must disable BH
3101		 */
3102		return false;
3103
3104	__lock_sock(sk);
3105	sk->sk_lock.owned = 1;
3106	spin_unlock(&sk->sk_lock.slock);
3107	/*
3108	 * The sk_lock has mutex_lock() semantics here:
3109	 */
3110	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
3111	local_bh_enable();
3112	return true;
3113}
3114EXPORT_SYMBOL(lock_sock_fast);
3115
3116int sock_gettstamp(struct socket *sock, void __user *userstamp,
3117		   bool timeval, bool time32)
3118{
3119	struct sock *sk = sock->sk;
3120	struct timespec64 ts;
 
 
 
 
 
 
 
 
 
 
 
3121
3122	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3123	ts = ktime_to_timespec64(sock_read_timestamp(sk));
 
 
 
 
3124	if (ts.tv_sec == -1)
3125		return -ENOENT;
3126	if (ts.tv_sec == 0) {
3127		ktime_t kt = ktime_get_real();
3128		sock_write_timestamp(sk, kt);
3129		ts = ktime_to_timespec64(kt);
3130	}
3131
3132	if (timeval)
3133		ts.tv_nsec /= 1000;
3134
3135#ifdef CONFIG_COMPAT_32BIT_TIME
3136	if (time32)
3137		return put_old_timespec32(&ts, userstamp);
3138#endif
3139#ifdef CONFIG_SPARC64
3140	/* beware of padding in sparc64 timeval */
3141	if (timeval && !in_compat_syscall()) {
3142		struct __kernel_old_timeval __user tv = {
3143			.tv_sec = ts.tv_sec,
3144			.tv_usec = ts.tv_nsec,
3145		};
3146		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3147			return -EFAULT;
3148		return 0;
3149	}
3150#endif
3151	return put_timespec64(&ts, userstamp);
3152}
3153EXPORT_SYMBOL(sock_gettstamp);
3154
3155void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3156{
3157	if (!sock_flag(sk, flag)) {
3158		unsigned long previous_flags = sk->sk_flags;
3159
3160		sock_set_flag(sk, flag);
3161		/*
3162		 * we just set one of the two flags which require net
3163		 * time stamping, but time stamping might have been on
3164		 * already because of the other one
3165		 */
3166		if (sock_needs_netstamp(sk) &&
3167		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3168			net_enable_timestamp();
3169	}
3170}
3171
3172int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3173		       int level, int type)
3174{
3175	struct sock_exterr_skb *serr;
3176	struct sk_buff *skb;
3177	int copied, err;
3178
3179	err = -EAGAIN;
3180	skb = sock_dequeue_err_skb(sk);
3181	if (skb == NULL)
3182		goto out;
3183
3184	copied = skb->len;
3185	if (copied > len) {
3186		msg->msg_flags |= MSG_TRUNC;
3187		copied = len;
3188	}
3189	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3190	if (err)
3191		goto out_free_skb;
3192
3193	sock_recv_timestamp(msg, sk, skb);
3194
3195	serr = SKB_EXT_ERR(skb);
3196	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3197
3198	msg->msg_flags |= MSG_ERRQUEUE;
3199	err = copied;
3200
3201out_free_skb:
3202	kfree_skb(skb);
3203out:
3204	return err;
3205}
3206EXPORT_SYMBOL(sock_recv_errqueue);
3207
3208/*
3209 *	Get a socket option on an socket.
3210 *
3211 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3212 *	asynchronous errors should be reported by getsockopt. We assume
3213 *	this means if you specify SO_ERROR (otherwise whats the point of it).
3214 */
3215int sock_common_getsockopt(struct socket *sock, int level, int optname,
3216			   char __user *optval, int __user *optlen)
3217{
3218	struct sock *sk = sock->sk;
3219
3220	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3221}
3222EXPORT_SYMBOL(sock_common_getsockopt);
3223
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3224int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3225			int flags)
3226{
3227	struct sock *sk = sock->sk;
3228	int addr_len = 0;
3229	int err;
3230
3231	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3232				   flags & ~MSG_DONTWAIT, &addr_len);
3233	if (err >= 0)
3234		msg->msg_namelen = addr_len;
3235	return err;
3236}
3237EXPORT_SYMBOL(sock_common_recvmsg);
3238
3239/*
3240 *	Set socket options on an inet socket.
3241 */
3242int sock_common_setsockopt(struct socket *sock, int level, int optname,
3243			   sockptr_t optval, unsigned int optlen)
3244{
3245	struct sock *sk = sock->sk;
3246
3247	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3248}
3249EXPORT_SYMBOL(sock_common_setsockopt);
3250
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3251void sk_common_release(struct sock *sk)
3252{
3253	if (sk->sk_prot->destroy)
3254		sk->sk_prot->destroy(sk);
3255
3256	/*
3257	 * Observation: when sk_common_release is called, processes have
3258	 * no access to socket. But net still has.
3259	 * Step one, detach it from networking:
3260	 *
3261	 * A. Remove from hash tables.
3262	 */
3263
3264	sk->sk_prot->unhash(sk);
3265
3266	/*
3267	 * In this point socket cannot receive new packets, but it is possible
3268	 * that some packets are in flight because some CPU runs receiver and
3269	 * did hash table lookup before we unhashed socket. They will achieve
3270	 * receive queue and will be purged by socket destructor.
3271	 *
3272	 * Also we still have packets pending on receive queue and probably,
3273	 * our own packets waiting in device queues. sock_destroy will drain
3274	 * receive queue, but transmitted packets will delay socket destruction
3275	 * until the last reference will be released.
3276	 */
3277
3278	sock_orphan(sk);
3279
3280	xfrm_sk_free_policy(sk);
3281
3282	sk_refcnt_debug_release(sk);
3283
 
 
 
 
 
3284	sock_put(sk);
3285}
3286EXPORT_SYMBOL(sk_common_release);
3287
3288void sk_get_meminfo(const struct sock *sk, u32 *mem)
3289{
3290	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3291
3292	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3293	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3294	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3295	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3296	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3297	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3298	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3299	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3300	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3301}
3302
3303#ifdef CONFIG_PROC_FS
3304#define PROTO_INUSE_NR	64	/* should be enough for the first time */
3305struct prot_inuse {
3306	int val[PROTO_INUSE_NR];
3307};
3308
3309static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3310
 
3311void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3312{
3313	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3314}
3315EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3316
3317int sock_prot_inuse_get(struct net *net, struct proto *prot)
3318{
3319	int cpu, idx = prot->inuse_idx;
3320	int res = 0;
3321
3322	for_each_possible_cpu(cpu)
3323		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3324
3325	return res >= 0 ? res : 0;
3326}
3327EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3328
3329static void sock_inuse_add(struct net *net, int val)
3330{
3331	this_cpu_add(*net->core.sock_inuse, val);
3332}
3333
3334int sock_inuse_get(struct net *net)
3335{
3336	int cpu, res = 0;
3337
3338	for_each_possible_cpu(cpu)
3339		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3340
3341	return res;
3342}
3343
3344EXPORT_SYMBOL_GPL(sock_inuse_get);
3345
3346static int __net_init sock_inuse_init_net(struct net *net)
3347{
3348	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3349	if (net->core.prot_inuse == NULL)
3350		return -ENOMEM;
3351
3352	net->core.sock_inuse = alloc_percpu(int);
3353	if (net->core.sock_inuse == NULL)
3354		goto out;
3355
3356	return 0;
3357
3358out:
3359	free_percpu(net->core.prot_inuse);
3360	return -ENOMEM;
3361}
3362
3363static void __net_exit sock_inuse_exit_net(struct net *net)
3364{
3365	free_percpu(net->core.prot_inuse);
3366	free_percpu(net->core.sock_inuse);
3367}
3368
3369static struct pernet_operations net_inuse_ops = {
3370	.init = sock_inuse_init_net,
3371	.exit = sock_inuse_exit_net,
3372};
3373
3374static __init int net_inuse_init(void)
3375{
3376	if (register_pernet_subsys(&net_inuse_ops))
3377		panic("Cannot initialize net inuse counters");
3378
3379	return 0;
3380}
3381
3382core_initcall(net_inuse_init);
 
 
3383
3384static int assign_proto_idx(struct proto *prot)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3385{
3386	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3387
3388	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3389		pr_err("PROTO_INUSE_NR exhausted\n");
3390		return -ENOSPC;
3391	}
3392
3393	set_bit(prot->inuse_idx, proto_inuse_idx);
3394	return 0;
3395}
3396
3397static void release_proto_idx(struct proto *prot)
3398{
3399	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3400		clear_bit(prot->inuse_idx, proto_inuse_idx);
3401}
3402#else
3403static inline int assign_proto_idx(struct proto *prot)
3404{
3405	return 0;
3406}
3407
3408static inline void release_proto_idx(struct proto *prot)
3409{
3410}
3411
3412static void sock_inuse_add(struct net *net, int val)
3413{
3414}
3415#endif
3416
3417static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3418{
3419	if (!twsk_prot)
3420		return;
3421	kfree(twsk_prot->twsk_slab_name);
3422	twsk_prot->twsk_slab_name = NULL;
3423	kmem_cache_destroy(twsk_prot->twsk_slab);
3424	twsk_prot->twsk_slab = NULL;
3425}
3426
3427static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3428{
3429	if (!rsk_prot)
3430		return;
3431	kfree(rsk_prot->slab_name);
3432	rsk_prot->slab_name = NULL;
3433	kmem_cache_destroy(rsk_prot->slab);
3434	rsk_prot->slab = NULL;
3435}
3436
3437static int req_prot_init(const struct proto *prot)
3438{
3439	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3440
3441	if (!rsk_prot)
3442		return 0;
3443
3444	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3445					prot->name);
3446	if (!rsk_prot->slab_name)
3447		return -ENOMEM;
3448
3449	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3450					   rsk_prot->obj_size, 0,
3451					   SLAB_ACCOUNT | prot->slab_flags,
3452					   NULL);
3453
3454	if (!rsk_prot->slab) {
3455		pr_crit("%s: Can't create request sock SLAB cache!\n",
3456			prot->name);
3457		return -ENOMEM;
3458	}
3459	return 0;
3460}
3461
3462int proto_register(struct proto *prot, int alloc_slab)
3463{
3464	int ret = -ENOBUFS;
3465
3466	if (alloc_slab) {
3467		prot->slab = kmem_cache_create_usercopy(prot->name,
3468					prot->obj_size, 0,
3469					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3470					prot->slab_flags,
3471					prot->useroffset, prot->usersize,
3472					NULL);
3473
3474		if (prot->slab == NULL) {
3475			pr_crit("%s: Can't create sock SLAB cache!\n",
3476				prot->name);
3477			goto out;
3478		}
3479
3480		if (req_prot_init(prot))
3481			goto out_free_request_sock_slab;
3482
3483		if (prot->twsk_prot != NULL) {
3484			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3485
3486			if (prot->twsk_prot->twsk_slab_name == NULL)
3487				goto out_free_request_sock_slab;
3488
3489			prot->twsk_prot->twsk_slab =
3490				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3491						  prot->twsk_prot->twsk_obj_size,
3492						  0,
3493						  SLAB_ACCOUNT |
3494						  prot->slab_flags,
3495						  NULL);
3496			if (prot->twsk_prot->twsk_slab == NULL)
3497				goto out_free_timewait_sock_slab;
3498		}
3499	}
3500
3501	mutex_lock(&proto_list_mutex);
3502	ret = assign_proto_idx(prot);
3503	if (ret) {
3504		mutex_unlock(&proto_list_mutex);
3505		goto out_free_timewait_sock_slab;
3506	}
3507	list_add(&prot->node, &proto_list);
 
3508	mutex_unlock(&proto_list_mutex);
3509	return ret;
3510
3511out_free_timewait_sock_slab:
3512	if (alloc_slab && prot->twsk_prot)
3513		tw_prot_cleanup(prot->twsk_prot);
3514out_free_request_sock_slab:
3515	if (alloc_slab) {
3516		req_prot_cleanup(prot->rsk_prot);
3517
3518		kmem_cache_destroy(prot->slab);
3519		prot->slab = NULL;
3520	}
3521out:
3522	return ret;
3523}
3524EXPORT_SYMBOL(proto_register);
3525
3526void proto_unregister(struct proto *prot)
3527{
3528	mutex_lock(&proto_list_mutex);
3529	release_proto_idx(prot);
3530	list_del(&prot->node);
3531	mutex_unlock(&proto_list_mutex);
3532
3533	kmem_cache_destroy(prot->slab);
3534	prot->slab = NULL;
3535
3536	req_prot_cleanup(prot->rsk_prot);
3537	tw_prot_cleanup(prot->twsk_prot);
3538}
3539EXPORT_SYMBOL(proto_unregister);
3540
3541int sock_load_diag_module(int family, int protocol)
3542{
3543	if (!protocol) {
3544		if (!sock_is_registered(family))
3545			return -ENOENT;
3546
3547		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3548				      NETLINK_SOCK_DIAG, family);
 
 
3549	}
3550
3551#ifdef CONFIG_INET
3552	if (family == AF_INET &&
3553	    protocol != IPPROTO_RAW &&
3554	    protocol < MAX_INET_PROTOS &&
3555	    !rcu_access_pointer(inet_protos[protocol]))
3556		return -ENOENT;
3557#endif
3558
3559	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3560			      NETLINK_SOCK_DIAG, family, protocol);
3561}
3562EXPORT_SYMBOL(sock_load_diag_module);
3563
3564#ifdef CONFIG_PROC_FS
3565static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3566	__acquires(proto_list_mutex)
3567{
3568	mutex_lock(&proto_list_mutex);
3569	return seq_list_start_head(&proto_list, *pos);
3570}
3571
3572static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3573{
3574	return seq_list_next(v, &proto_list, pos);
3575}
3576
3577static void proto_seq_stop(struct seq_file *seq, void *v)
3578	__releases(proto_list_mutex)
3579{
3580	mutex_unlock(&proto_list_mutex);
3581}
3582
3583static char proto_method_implemented(const void *method)
3584{
3585	return method == NULL ? 'n' : 'y';
3586}
3587static long sock_prot_memory_allocated(struct proto *proto)
3588{
3589	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3590}
3591
3592static const char *sock_prot_memory_pressure(struct proto *proto)
3593{
3594	return proto->memory_pressure != NULL ?
3595	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3596}
3597
3598static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3599{
3600
3601	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3602			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3603		   proto->name,
3604		   proto->obj_size,
3605		   sock_prot_inuse_get(seq_file_net(seq), proto),
3606		   sock_prot_memory_allocated(proto),
3607		   sock_prot_memory_pressure(proto),
3608		   proto->max_header,
3609		   proto->slab == NULL ? "no" : "yes",
3610		   module_name(proto->owner),
3611		   proto_method_implemented(proto->close),
3612		   proto_method_implemented(proto->connect),
3613		   proto_method_implemented(proto->disconnect),
3614		   proto_method_implemented(proto->accept),
3615		   proto_method_implemented(proto->ioctl),
3616		   proto_method_implemented(proto->init),
3617		   proto_method_implemented(proto->destroy),
3618		   proto_method_implemented(proto->shutdown),
3619		   proto_method_implemented(proto->setsockopt),
3620		   proto_method_implemented(proto->getsockopt),
3621		   proto_method_implemented(proto->sendmsg),
3622		   proto_method_implemented(proto->recvmsg),
3623		   proto_method_implemented(proto->sendpage),
3624		   proto_method_implemented(proto->bind),
3625		   proto_method_implemented(proto->backlog_rcv),
3626		   proto_method_implemented(proto->hash),
3627		   proto_method_implemented(proto->unhash),
3628		   proto_method_implemented(proto->get_port),
3629		   proto_method_implemented(proto->enter_memory_pressure));
3630}
3631
3632static int proto_seq_show(struct seq_file *seq, void *v)
3633{
3634	if (v == &proto_list)
3635		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3636			   "protocol",
3637			   "size",
3638			   "sockets",
3639			   "memory",
3640			   "press",
3641			   "maxhdr",
3642			   "slab",
3643			   "module",
3644			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3645	else
3646		proto_seq_printf(seq, list_entry(v, struct proto, node));
3647	return 0;
3648}
3649
3650static const struct seq_operations proto_seq_ops = {
3651	.start  = proto_seq_start,
3652	.next   = proto_seq_next,
3653	.stop   = proto_seq_stop,
3654	.show   = proto_seq_show,
3655};
3656
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3657static __net_init int proto_init_net(struct net *net)
3658{
3659	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3660			sizeof(struct seq_net_private)))
3661		return -ENOMEM;
3662
3663	return 0;
3664}
3665
3666static __net_exit void proto_exit_net(struct net *net)
3667{
3668	remove_proc_entry("protocols", net->proc_net);
3669}
3670
3671
3672static __net_initdata struct pernet_operations proto_net_ops = {
3673	.init = proto_init_net,
3674	.exit = proto_exit_net,
3675};
3676
3677static int __init proto_init(void)
3678{
3679	return register_pernet_subsys(&proto_net_ops);
3680}
3681
3682subsys_initcall(proto_init);
3683
3684#endif /* PROC_FS */
3685
3686#ifdef CONFIG_NET_RX_BUSY_POLL
3687bool sk_busy_loop_end(void *p, unsigned long start_time)
3688{
3689	struct sock *sk = p;
3690
3691	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
3692	       sk_busy_loop_timeout(sk, start_time);
3693}
3694EXPORT_SYMBOL(sk_busy_loop_end);
3695#endif /* CONFIG_NET_RX_BUSY_POLL */
3696
3697int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
3698{
3699	if (!sk->sk_prot->bind_add)
3700		return -EOPNOTSUPP;
3701	return sk->sk_prot->bind_add(sk, addr, addr_len);
3702}
3703EXPORT_SYMBOL(sock_bind_add);
v4.6
 
   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/timer.h>
 106#include <linux/string.h>
 107#include <linux/sockios.h>
 108#include <linux/net.h>
 109#include <linux/mm.h>
 110#include <linux/slab.h>
 111#include <linux/interrupt.h>
 112#include <linux/poll.h>
 113#include <linux/tcp.h>
 114#include <linux/init.h>
 115#include <linux/highmem.h>
 116#include <linux/user_namespace.h>
 117#include <linux/static_key.h>
 118#include <linux/memcontrol.h>
 119#include <linux/prefetch.h>
 
 120
 121#include <asm/uaccess.h>
 122
 123#include <linux/netdevice.h>
 124#include <net/protocol.h>
 125#include <linux/skbuff.h>
 126#include <net/net_namespace.h>
 127#include <net/request_sock.h>
 128#include <net/sock.h>
 129#include <linux/net_tstamp.h>
 130#include <net/xfrm.h>
 131#include <linux/ipsec.h>
 132#include <net/cls_cgroup.h>
 133#include <net/netprio_cgroup.h>
 134#include <linux/sock_diag.h>
 135
 136#include <linux/filter.h>
 137#include <net/sock_reuseport.h>
 
 138
 139#include <trace/events/sock.h>
 140
 141#ifdef CONFIG_INET
 142#include <net/tcp.h>
 143#endif
 144
 145#include <net/busy_poll.h>
 146
 147static DEFINE_MUTEX(proto_list_mutex);
 148static LIST_HEAD(proto_list);
 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:
 
 201 */
 202static struct lock_class_key af_family_keys[AF_MAX];
 
 203static struct lock_class_key af_family_slock_keys[AF_MAX];
 
 204
 205/*
 206 * Make lock validator output more readable. (we pre-construct these
 207 * strings build-time, so that runtime initialization of socket
 208 * locks is fast):
 209 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 210static const char *const af_family_key_strings[AF_MAX+1] = {
 211  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
 212  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
 213  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
 214  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
 215  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
 216  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
 217  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
 218  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
 219  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
 220  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
 221  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
 222  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
 223  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
 224  "sk_lock-AF_NFC"   , "sk_lock-AF_VSOCK"    , "sk_lock-AF_KCM"      ,
 225  "sk_lock-AF_MAX"
 226};
 227static const char *const af_family_slock_key_strings[AF_MAX+1] = {
 228  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
 229  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
 230  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
 231  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
 232  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
 233  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
 234  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
 235  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
 236  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
 237  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
 238  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
 239  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
 240  "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
 241  "slock-AF_NFC"   , "slock-AF_VSOCK"    ,"slock-AF_KCM"       ,
 242  "slock-AF_MAX"
 243};
 244static const char *const af_family_clock_key_strings[AF_MAX+1] = {
 245  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
 246  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
 247  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
 248  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
 249  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
 250  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
 251  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
 252  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
 253  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
 254  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
 255  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
 256  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
 257  "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
 258  "clock-AF_NFC"   , "clock-AF_VSOCK"    , "clock-AF_KCM"      ,
 259  "clock-AF_MAX"
 
 
 
 
 
 260};
 261
 262/*
 263 * sk_callback_lock locking rules are per-address-family,
 264 * so split the lock classes by using a per-AF key:
 265 */
 266static struct lock_class_key af_callback_keys[AF_MAX];
 267
 268/* Take into consideration the size of the struct sk_buff overhead in the
 269 * determination of these values, since that is non-constant across
 270 * platforms.  This makes socket queueing behavior and performance
 271 * not depend upon such differences.
 272 */
 273#define _SK_MEM_PACKETS		256
 274#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
 275#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
 276#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
 277
 278/* Run time adjustable parameters. */
 279__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
 280EXPORT_SYMBOL(sysctl_wmem_max);
 281__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
 282EXPORT_SYMBOL(sysctl_rmem_max);
 283__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
 284__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
 285
 286/* Maximal space eaten by iovec or ancillary data plus some space */
 287int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
 288EXPORT_SYMBOL(sysctl_optmem_max);
 289
 290int sysctl_tstamp_allow_data __read_mostly = 1;
 291
 292struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
 293EXPORT_SYMBOL_GPL(memalloc_socks);
 294
 295/**
 296 * sk_set_memalloc - sets %SOCK_MEMALLOC
 297 * @sk: socket to set it on
 298 *
 299 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
 300 * It's the responsibility of the admin to adjust min_free_kbytes
 301 * to meet the requirements
 302 */
 303void sk_set_memalloc(struct sock *sk)
 304{
 305	sock_set_flag(sk, SOCK_MEMALLOC);
 306	sk->sk_allocation |= __GFP_MEMALLOC;
 307	static_key_slow_inc(&memalloc_socks);
 308}
 309EXPORT_SYMBOL_GPL(sk_set_memalloc);
 310
 311void sk_clear_memalloc(struct sock *sk)
 312{
 313	sock_reset_flag(sk, SOCK_MEMALLOC);
 314	sk->sk_allocation &= ~__GFP_MEMALLOC;
 315	static_key_slow_dec(&memalloc_socks);
 316
 317	/*
 318	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
 319	 * progress of swapping. SOCK_MEMALLOC may be cleared while
 320	 * it has rmem allocations due to the last swapfile being deactivated
 321	 * but there is a risk that the socket is unusable due to exceeding
 322	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
 323	 */
 324	sk_mem_reclaim(sk);
 325}
 326EXPORT_SYMBOL_GPL(sk_clear_memalloc);
 327
 328int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 329{
 330	int ret;
 331	unsigned long pflags = current->flags;
 332
 333	/* these should have been dropped before queueing */
 334	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
 335
 336	current->flags |= PF_MEMALLOC;
 337	ret = sk->sk_backlog_rcv(sk, skb);
 338	tsk_restore_flags(current, pflags, PF_MEMALLOC);
 339
 340	return ret;
 341}
 342EXPORT_SYMBOL(__sk_backlog_rcv);
 343
 344static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
 345{
 346	struct timeval tv;
 347
 348	if (optlen < sizeof(tv))
 349		return -EINVAL;
 350	if (copy_from_user(&tv, optval, sizeof(tv)))
 351		return -EFAULT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 352	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
 353		return -EDOM;
 354
 355	if (tv.tv_sec < 0) {
 356		static int warned __read_mostly;
 357
 358		*timeo_p = 0;
 359		if (warned < 10 && net_ratelimit()) {
 360			warned++;
 361			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
 362				__func__, current->comm, task_pid_nr(current));
 363		}
 364		return 0;
 365	}
 366	*timeo_p = MAX_SCHEDULE_TIMEOUT;
 367	if (tv.tv_sec == 0 && tv.tv_usec == 0)
 368		return 0;
 369	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
 370		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
 371	return 0;
 372}
 373
 374static void sock_warn_obsolete_bsdism(const char *name)
 375{
 376	static int warned;
 377	static char warncomm[TASK_COMM_LEN];
 378	if (strcmp(warncomm, current->comm) && warned < 5) {
 379		strcpy(warncomm,  current->comm);
 380		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
 381			warncomm, name);
 382		warned++;
 383	}
 384}
 385
 386static bool sock_needs_netstamp(const struct sock *sk)
 387{
 388	switch (sk->sk_family) {
 389	case AF_UNSPEC:
 390	case AF_UNIX:
 391		return false;
 392	default:
 393		return true;
 394	}
 395}
 396
 397static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
 398{
 399	if (sk->sk_flags & flags) {
 400		sk->sk_flags &= ~flags;
 401		if (sock_needs_netstamp(sk) &&
 402		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
 403			net_disable_timestamp();
 404	}
 405}
 406
 407
 408int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 409{
 410	int err;
 411	unsigned long flags;
 412	struct sk_buff_head *list = &sk->sk_receive_queue;
 413
 414	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
 415		atomic_inc(&sk->sk_drops);
 416		trace_sock_rcvqueue_full(sk, skb);
 417		return -ENOMEM;
 418	}
 419
 420	err = sk_filter(sk, skb);
 421	if (err)
 422		return err;
 423
 424	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
 425		atomic_inc(&sk->sk_drops);
 426		return -ENOBUFS;
 427	}
 428
 429	skb->dev = NULL;
 430	skb_set_owner_r(skb, sk);
 431
 432	/* we escape from rcu protected region, make sure we dont leak
 433	 * a norefcounted dst
 434	 */
 435	skb_dst_force(skb);
 436
 437	spin_lock_irqsave(&list->lock, flags);
 438	sock_skb_set_dropcount(sk, skb);
 439	__skb_queue_tail(list, skb);
 440	spin_unlock_irqrestore(&list->lock, flags);
 441
 442	if (!sock_flag(sk, SOCK_DEAD))
 443		sk->sk_data_ready(sk);
 444	return 0;
 445}
 
 
 
 
 
 
 
 
 
 
 
 
 446EXPORT_SYMBOL(sock_queue_rcv_skb);
 447
 448int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
 
 449{
 450	int rc = NET_RX_SUCCESS;
 451
 452	if (sk_filter(sk, skb))
 453		goto discard_and_relse;
 454
 455	skb->dev = NULL;
 456
 457	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
 458		atomic_inc(&sk->sk_drops);
 459		goto discard_and_relse;
 460	}
 461	if (nested)
 462		bh_lock_sock_nested(sk);
 463	else
 464		bh_lock_sock(sk);
 465	if (!sock_owned_by_user(sk)) {
 466		/*
 467		 * trylock + unlock semantics:
 468		 */
 469		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 470
 471		rc = sk_backlog_rcv(sk, skb);
 472
 473		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
 474	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 475		bh_unlock_sock(sk);
 476		atomic_inc(&sk->sk_drops);
 477		goto discard_and_relse;
 478	}
 479
 480	bh_unlock_sock(sk);
 481out:
 482	sock_put(sk);
 
 483	return rc;
 484discard_and_relse:
 485	kfree_skb(skb);
 486	goto out;
 487}
 488EXPORT_SYMBOL(sk_receive_skb);
 489
 490struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
 491{
 492	struct dst_entry *dst = __sk_dst_get(sk);
 493
 494	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 495		sk_tx_queue_clear(sk);
 
 496		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
 497		dst_release(dst);
 498		return NULL;
 499	}
 500
 501	return dst;
 502}
 503EXPORT_SYMBOL(__sk_dst_check);
 504
 505struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
 506{
 507	struct dst_entry *dst = sk_dst_get(sk);
 508
 509	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
 510		sk_dst_reset(sk);
 511		dst_release(dst);
 512		return NULL;
 513	}
 514
 515	return dst;
 516}
 517EXPORT_SYMBOL(sk_dst_check);
 518
 519static int sock_setbindtodevice(struct sock *sk, char __user *optval,
 520				int optlen)
 521{
 522	int ret = -ENOPROTOOPT;
 523#ifdef CONFIG_NETDEVICES
 524	struct net *net = sock_net(sk);
 525	char devname[IFNAMSIZ];
 526	int index;
 527
 528	/* Sorry... */
 529	ret = -EPERM;
 530	if (!ns_capable(net->user_ns, CAP_NET_RAW))
 531		goto out;
 532
 533	ret = -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 534	if (optlen < 0)
 535		goto out;
 536
 537	/* Bind this socket to a particular device like "eth0",
 538	 * as specified in the passed interface name. If the
 539	 * name is "" or the option length is zero the socket
 540	 * is not bound.
 541	 */
 542	if (optlen > IFNAMSIZ - 1)
 543		optlen = IFNAMSIZ - 1;
 544	memset(devname, 0, sizeof(devname));
 545
 546	ret = -EFAULT;
 547	if (copy_from_user(devname, optval, optlen))
 548		goto out;
 549
 550	index = 0;
 551	if (devname[0] != '\0') {
 552		struct net_device *dev;
 553
 554		rcu_read_lock();
 555		dev = dev_get_by_name_rcu(net, devname);
 556		if (dev)
 557			index = dev->ifindex;
 558		rcu_read_unlock();
 559		ret = -ENODEV;
 560		if (!dev)
 561			goto out;
 562	}
 563
 564	lock_sock(sk);
 565	sk->sk_bound_dev_if = index;
 566	sk_dst_reset(sk);
 567	release_sock(sk);
 568
 569	ret = 0;
 570
 571out:
 572#endif
 573
 574	return ret;
 575}
 576
 577static int sock_getbindtodevice(struct sock *sk, char __user *optval,
 578				int __user *optlen, int len)
 579{
 580	int ret = -ENOPROTOOPT;
 581#ifdef CONFIG_NETDEVICES
 582	struct net *net = sock_net(sk);
 583	char devname[IFNAMSIZ];
 584
 585	if (sk->sk_bound_dev_if == 0) {
 586		len = 0;
 587		goto zero;
 588	}
 589
 590	ret = -EINVAL;
 591	if (len < IFNAMSIZ)
 592		goto out;
 593
 594	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
 595	if (ret)
 596		goto out;
 597
 598	len = strlen(devname) + 1;
 599
 600	ret = -EFAULT;
 601	if (copy_to_user(optval, devname, len))
 602		goto out;
 603
 604zero:
 605	ret = -EFAULT;
 606	if (put_user(len, optlen))
 607		goto out;
 608
 609	ret = 0;
 610
 611out:
 612#endif
 613
 614	return ret;
 615}
 616
 617static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
 618{
 619	if (valbool)
 620		sock_set_flag(sk, bit);
 621	else
 622		sock_reset_flag(sk, bit);
 623}
 624
 625bool sk_mc_loop(struct sock *sk)
 626{
 627	if (dev_recursion_level())
 628		return false;
 629	if (!sk)
 630		return true;
 631	switch (sk->sk_family) {
 632	case AF_INET:
 633		return inet_sk(sk)->mc_loop;
 634#if IS_ENABLED(CONFIG_IPV6)
 635	case AF_INET6:
 636		return inet6_sk(sk)->mc_loop;
 637#endif
 638	}
 639	WARN_ON(1);
 640	return true;
 641}
 642EXPORT_SYMBOL(sk_mc_loop);
 643
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 644/*
 645 *	This is meant for all protocols to use and covers goings on
 646 *	at the socket level. Everything here is generic.
 647 */
 648
 649int sock_setsockopt(struct socket *sock, int level, int optname,
 650		    char __user *optval, unsigned int optlen)
 651{
 
 652	struct sock *sk = sock->sk;
 653	int val;
 654	int valbool;
 655	struct linger ling;
 656	int ret = 0;
 657
 658	/*
 659	 *	Options without arguments
 660	 */
 661
 662	if (optname == SO_BINDTODEVICE)
 663		return sock_setbindtodevice(sk, optval, optlen);
 664
 665	if (optlen < sizeof(int))
 666		return -EINVAL;
 667
 668	if (get_user(val, (int __user *)optval))
 669		return -EFAULT;
 670
 671	valbool = val ? 1 : 0;
 672
 673	lock_sock(sk);
 674
 675	switch (optname) {
 676	case SO_DEBUG:
 677		if (val && !capable(CAP_NET_ADMIN))
 678			ret = -EACCES;
 679		else
 680			sock_valbool_flag(sk, SOCK_DBG, valbool);
 681		break;
 682	case SO_REUSEADDR:
 683		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
 684		break;
 685	case SO_REUSEPORT:
 686		sk->sk_reuseport = valbool;
 687		break;
 688	case SO_TYPE:
 689	case SO_PROTOCOL:
 690	case SO_DOMAIN:
 691	case SO_ERROR:
 692		ret = -ENOPROTOOPT;
 693		break;
 694	case SO_DONTROUTE:
 695		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
 
 696		break;
 697	case SO_BROADCAST:
 698		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
 699		break;
 700	case SO_SNDBUF:
 701		/* Don't error on this BSD doesn't and if you think
 702		 * about it this is right. Otherwise apps have to
 703		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
 704		 * are treated in BSD as hints
 705		 */
 706		val = min_t(u32, val, sysctl_wmem_max);
 707set_sndbuf:
 
 
 
 
 708		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
 709		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
 
 710		/* Wake up sending tasks if we upped the value. */
 711		sk->sk_write_space(sk);
 712		break;
 713
 714	case SO_SNDBUFFORCE:
 715		if (!capable(CAP_NET_ADMIN)) {
 716			ret = -EPERM;
 717			break;
 718		}
 
 
 
 
 
 
 719		goto set_sndbuf;
 720
 721	case SO_RCVBUF:
 722		/* Don't error on this BSD doesn't and if you think
 723		 * about it this is right. Otherwise apps have to
 724		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
 725		 * are treated in BSD as hints
 726		 */
 727		val = min_t(u32, val, sysctl_rmem_max);
 728set_rcvbuf:
 729		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 730		/*
 731		 * We double it on the way in to account for
 732		 * "struct sk_buff" etc. overhead.   Applications
 733		 * assume that the SO_RCVBUF setting they make will
 734		 * allow that much actual data to be received on that
 735		 * socket.
 736		 *
 737		 * Applications are unaware that "struct sk_buff" and
 738		 * other overheads allocate from the receive buffer
 739		 * during socket buffer allocation.
 740		 *
 741		 * And after considering the possible alternatives,
 742		 * returning the value we actually used in getsockopt
 743		 * is the most desirable behavior.
 744		 */
 745		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
 746		break;
 747
 748	case SO_RCVBUFFORCE:
 749		if (!capable(CAP_NET_ADMIN)) {
 750			ret = -EPERM;
 751			break;
 752		}
 753		goto set_rcvbuf;
 
 
 
 
 
 754
 755	case SO_KEEPALIVE:
 756#ifdef CONFIG_INET
 757		if (sk->sk_protocol == IPPROTO_TCP &&
 758		    sk->sk_type == SOCK_STREAM)
 759			tcp_set_keepalive(sk, valbool);
 760#endif
 761		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
 762		break;
 763
 764	case SO_OOBINLINE:
 765		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
 766		break;
 767
 768	case SO_NO_CHECK:
 769		sk->sk_no_check_tx = valbool;
 770		break;
 771
 772	case SO_PRIORITY:
 773		if ((val >= 0 && val <= 6) ||
 774		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 775			sk->sk_priority = val;
 776		else
 777			ret = -EPERM;
 778		break;
 779
 780	case SO_LINGER:
 781		if (optlen < sizeof(ling)) {
 782			ret = -EINVAL;	/* 1003.1g */
 783			break;
 784		}
 785		if (copy_from_user(&ling, optval, sizeof(ling))) {
 786			ret = -EFAULT;
 787			break;
 788		}
 789		if (!ling.l_onoff)
 790			sock_reset_flag(sk, SOCK_LINGER);
 791		else {
 792#if (BITS_PER_LONG == 32)
 793			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
 794				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
 795			else
 796#endif
 797				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
 798			sock_set_flag(sk, SOCK_LINGER);
 799		}
 800		break;
 801
 802	case SO_BSDCOMPAT:
 803		sock_warn_obsolete_bsdism("setsockopt");
 804		break;
 805
 806	case SO_PASSCRED:
 807		if (valbool)
 808			set_bit(SOCK_PASSCRED, &sock->flags);
 809		else
 810			clear_bit(SOCK_PASSCRED, &sock->flags);
 811		break;
 812
 813	case SO_TIMESTAMP:
 814	case SO_TIMESTAMPNS:
 815		if (valbool)  {
 816			if (optname == SO_TIMESTAMP)
 817				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 818			else
 819				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
 820			sock_set_flag(sk, SOCK_RCVTSTAMP);
 821			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
 822		} else {
 823			sock_reset_flag(sk, SOCK_RCVTSTAMP);
 824			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
 825		}
 826		break;
 827
 828	case SO_TIMESTAMPING:
 
 
 
 
 
 829		if (val & ~SOF_TIMESTAMPING_MASK) {
 830			ret = -EINVAL;
 831			break;
 832		}
 833
 834		if (val & SOF_TIMESTAMPING_OPT_ID &&
 835		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
 836			if (sk->sk_protocol == IPPROTO_TCP &&
 837			    sk->sk_type == SOCK_STREAM) {
 838				if (sk->sk_state != TCP_ESTABLISHED) {
 
 839					ret = -EINVAL;
 840					break;
 841				}
 842				sk->sk_tskey = tcp_sk(sk)->snd_una;
 843			} else {
 844				sk->sk_tskey = 0;
 845			}
 846		}
 
 
 
 
 
 
 
 847		sk->sk_tsflags = val;
 848		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
 849			sock_enable_timestamp(sk,
 850					      SOCK_TIMESTAMPING_RX_SOFTWARE);
 851		else
 
 
 
 852			sock_disable_timestamp(sk,
 853					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
 
 854		break;
 855
 856	case SO_RCVLOWAT:
 857		if (val < 0)
 858			val = INT_MAX;
 859		sk->sk_rcvlowat = val ? : 1;
 
 
 
 860		break;
 861
 862	case SO_RCVTIMEO:
 863		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
 
 
 864		break;
 865
 866	case SO_SNDTIMEO:
 867		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
 
 
 868		break;
 869
 870	case SO_ATTACH_FILTER:
 871		ret = -EINVAL;
 872		if (optlen == sizeof(struct sock_fprog)) {
 873			struct sock_fprog fprog;
 874
 875			ret = -EFAULT;
 876			if (copy_from_user(&fprog, optval, sizeof(fprog)))
 877				break;
 878
 
 
 879			ret = sk_attach_filter(&fprog, sk);
 880		}
 881		break;
 882
 883	case SO_ATTACH_BPF:
 884		ret = -EINVAL;
 885		if (optlen == sizeof(u32)) {
 886			u32 ufd;
 887
 888			ret = -EFAULT;
 889			if (copy_from_user(&ufd, optval, sizeof(ufd)))
 890				break;
 891
 892			ret = sk_attach_bpf(ufd, sk);
 893		}
 894		break;
 895
 896	case SO_ATTACH_REUSEPORT_CBPF:
 897		ret = -EINVAL;
 898		if (optlen == sizeof(struct sock_fprog)) {
 899			struct sock_fprog fprog;
 900
 901			ret = -EFAULT;
 902			if (copy_from_user(&fprog, optval, sizeof(fprog)))
 903				break;
 904
 
 
 905			ret = sk_reuseport_attach_filter(&fprog, sk);
 906		}
 907		break;
 908
 909	case SO_ATTACH_REUSEPORT_EBPF:
 910		ret = -EINVAL;
 911		if (optlen == sizeof(u32)) {
 912			u32 ufd;
 913
 914			ret = -EFAULT;
 915			if (copy_from_user(&ufd, optval, sizeof(ufd)))
 916				break;
 917
 918			ret = sk_reuseport_attach_bpf(ufd, sk);
 919		}
 920		break;
 921
 
 
 
 
 922	case SO_DETACH_FILTER:
 923		ret = sk_detach_filter(sk);
 924		break;
 925
 926	case SO_LOCK_FILTER:
 927		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
 928			ret = -EPERM;
 929		else
 930			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
 931		break;
 932
 933	case SO_PASSSEC:
 934		if (valbool)
 935			set_bit(SOCK_PASSSEC, &sock->flags);
 936		else
 937			clear_bit(SOCK_PASSSEC, &sock->flags);
 938		break;
 939	case SO_MARK:
 940		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
 941			ret = -EPERM;
 942		else
 943			sk->sk_mark = val;
 
 
 944		break;
 945
 946	case SO_RXQ_OVFL:
 947		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
 948		break;
 949
 950	case SO_WIFI_STATUS:
 951		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
 952		break;
 953
 954	case SO_PEEK_OFF:
 955		if (sock->ops->set_peek_off)
 956			ret = sock->ops->set_peek_off(sk, val);
 957		else
 958			ret = -EOPNOTSUPP;
 959		break;
 960
 961	case SO_NOFCS:
 962		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
 963		break;
 964
 965	case SO_SELECT_ERR_QUEUE:
 966		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
 967		break;
 968
 969#ifdef CONFIG_NET_RX_BUSY_POLL
 970	case SO_BUSY_POLL:
 971		/* allow unprivileged users to decrease the value */
 972		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
 973			ret = -EPERM;
 974		else {
 975			if (val < 0)
 976				ret = -EINVAL;
 977			else
 978				sk->sk_ll_usec = val;
 979		}
 980		break;
 981#endif
 982
 983	case SO_MAX_PACING_RATE:
 984		sk->sk_max_pacing_rate = val;
 985		sk->sk_pacing_rate = min(sk->sk_pacing_rate,
 986					 sk->sk_max_pacing_rate);
 
 
 
 
 
 
 
 
 
 
 
 
 987		break;
 988
 989	case SO_INCOMING_CPU:
 990		sk->sk_incoming_cpu = val;
 991		break;
 992
 993	case SO_CNX_ADVICE:
 994		if (val == 1)
 995			dst_negative_advice(sk);
 996		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 997	default:
 998		ret = -ENOPROTOOPT;
 999		break;
1000	}
1001	release_sock(sk);
1002	return ret;
1003}
1004EXPORT_SYMBOL(sock_setsockopt);
1005
1006
1007static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1008			  struct ucred *ucred)
1009{
1010	ucred->pid = pid_vnr(pid);
1011	ucred->uid = ucred->gid = -1;
1012	if (cred) {
1013		struct user_namespace *current_ns = current_user_ns();
1014
1015		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1016		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1017	}
1018}
1019
 
 
 
 
 
 
 
 
 
 
 
 
1020int sock_getsockopt(struct socket *sock, int level, int optname,
1021		    char __user *optval, int __user *optlen)
1022{
1023	struct sock *sk = sock->sk;
1024
1025	union {
1026		int val;
 
 
1027		struct linger ling;
1028		struct timeval tm;
 
 
 
1029	} v;
1030
1031	int lv = sizeof(int);
1032	int len;
1033
1034	if (get_user(len, optlen))
1035		return -EFAULT;
1036	if (len < 0)
1037		return -EINVAL;
1038
1039	memset(&v, 0, sizeof(v));
1040
1041	switch (optname) {
1042	case SO_DEBUG:
1043		v.val = sock_flag(sk, SOCK_DBG);
1044		break;
1045
1046	case SO_DONTROUTE:
1047		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1048		break;
1049
1050	case SO_BROADCAST:
1051		v.val = sock_flag(sk, SOCK_BROADCAST);
1052		break;
1053
1054	case SO_SNDBUF:
1055		v.val = sk->sk_sndbuf;
1056		break;
1057
1058	case SO_RCVBUF:
1059		v.val = sk->sk_rcvbuf;
1060		break;
1061
1062	case SO_REUSEADDR:
1063		v.val = sk->sk_reuse;
1064		break;
1065
1066	case SO_REUSEPORT:
1067		v.val = sk->sk_reuseport;
1068		break;
1069
1070	case SO_KEEPALIVE:
1071		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1072		break;
1073
1074	case SO_TYPE:
1075		v.val = sk->sk_type;
1076		break;
1077
1078	case SO_PROTOCOL:
1079		v.val = sk->sk_protocol;
1080		break;
1081
1082	case SO_DOMAIN:
1083		v.val = sk->sk_family;
1084		break;
1085
1086	case SO_ERROR:
1087		v.val = -sock_error(sk);
1088		if (v.val == 0)
1089			v.val = xchg(&sk->sk_err_soft, 0);
1090		break;
1091
1092	case SO_OOBINLINE:
1093		v.val = sock_flag(sk, SOCK_URGINLINE);
1094		break;
1095
1096	case SO_NO_CHECK:
1097		v.val = sk->sk_no_check_tx;
1098		break;
1099
1100	case SO_PRIORITY:
1101		v.val = sk->sk_priority;
1102		break;
1103
1104	case SO_LINGER:
1105		lv		= sizeof(v.ling);
1106		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1107		v.ling.l_linger	= sk->sk_lingertime / HZ;
1108		break;
1109
1110	case SO_BSDCOMPAT:
1111		sock_warn_obsolete_bsdism("getsockopt");
1112		break;
1113
1114	case SO_TIMESTAMP:
1115		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
 
1116				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1117		break;
1118
1119	case SO_TIMESTAMPNS:
1120		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
 
 
 
 
 
 
 
 
1121		break;
1122
1123	case SO_TIMESTAMPING:
1124		v.val = sk->sk_tsflags;
1125		break;
1126
1127	case SO_RCVTIMEO:
1128		lv = sizeof(struct timeval);
1129		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1130			v.tm.tv_sec = 0;
1131			v.tm.tv_usec = 0;
1132		} else {
1133			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1134			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1135		}
1136		break;
1137
1138	case SO_SNDTIMEO:
1139		lv = sizeof(struct timeval);
1140		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1141			v.tm.tv_sec = 0;
1142			v.tm.tv_usec = 0;
1143		} else {
1144			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1145			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1146		}
1147		break;
1148
1149	case SO_RCVLOWAT:
1150		v.val = sk->sk_rcvlowat;
1151		break;
1152
1153	case SO_SNDLOWAT:
1154		v.val = 1;
1155		break;
1156
1157	case SO_PASSCRED:
1158		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1159		break;
1160
1161	case SO_PEERCRED:
1162	{
1163		struct ucred peercred;
1164		if (len > sizeof(peercred))
1165			len = sizeof(peercred);
1166		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1167		if (copy_to_user(optval, &peercred, len))
1168			return -EFAULT;
1169		goto lenout;
1170	}
1171
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1172	case SO_PEERNAME:
1173	{
1174		char address[128];
1175
1176		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
 
1177			return -ENOTCONN;
1178		if (lv < len)
1179			return -EINVAL;
1180		if (copy_to_user(optval, address, len))
1181			return -EFAULT;
1182		goto lenout;
1183	}
1184
1185	/* Dubious BSD thing... Probably nobody even uses it, but
1186	 * the UNIX standard wants it for whatever reason... -DaveM
1187	 */
1188	case SO_ACCEPTCONN:
1189		v.val = sk->sk_state == TCP_LISTEN;
1190		break;
1191
1192	case SO_PASSSEC:
1193		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1194		break;
1195
1196	case SO_PEERSEC:
1197		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1198
1199	case SO_MARK:
1200		v.val = sk->sk_mark;
1201		break;
1202
1203	case SO_RXQ_OVFL:
1204		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1205		break;
1206
1207	case SO_WIFI_STATUS:
1208		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1209		break;
1210
1211	case SO_PEEK_OFF:
1212		if (!sock->ops->set_peek_off)
1213			return -EOPNOTSUPP;
1214
1215		v.val = sk->sk_peek_off;
1216		break;
1217	case SO_NOFCS:
1218		v.val = sock_flag(sk, SOCK_NOFCS);
1219		break;
1220
1221	case SO_BINDTODEVICE:
1222		return sock_getbindtodevice(sk, optval, optlen, len);
1223
1224	case SO_GET_FILTER:
1225		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1226		if (len < 0)
1227			return len;
1228
1229		goto lenout;
1230
1231	case SO_LOCK_FILTER:
1232		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1233		break;
1234
1235	case SO_BPF_EXTENSIONS:
1236		v.val = bpf_tell_extensions();
1237		break;
1238
1239	case SO_SELECT_ERR_QUEUE:
1240		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1241		break;
1242
1243#ifdef CONFIG_NET_RX_BUSY_POLL
1244	case SO_BUSY_POLL:
1245		v.val = sk->sk_ll_usec;
1246		break;
1247#endif
1248
1249	case SO_MAX_PACING_RATE:
1250		v.val = sk->sk_max_pacing_rate;
 
 
 
 
 
 
1251		break;
1252
1253	case SO_INCOMING_CPU:
1254		v.val = sk->sk_incoming_cpu;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1255		break;
1256
1257	default:
1258		/* We implement the SO_SNDLOWAT etc to not be settable
1259		 * (1003.1g 7).
1260		 */
1261		return -ENOPROTOOPT;
1262	}
1263
1264	if (len > lv)
1265		len = lv;
1266	if (copy_to_user(optval, &v, len))
1267		return -EFAULT;
1268lenout:
1269	if (put_user(len, optlen))
1270		return -EFAULT;
1271	return 0;
1272}
1273
1274/*
1275 * Initialize an sk_lock.
1276 *
1277 * (We also register the sk_lock with the lock validator.)
1278 */
1279static inline void sock_lock_init(struct sock *sk)
1280{
1281	sock_lock_init_class_and_name(sk,
 
 
 
 
 
 
 
 
 
1282			af_family_slock_key_strings[sk->sk_family],
1283			af_family_slock_keys + sk->sk_family,
1284			af_family_key_strings[sk->sk_family],
1285			af_family_keys + sk->sk_family);
1286}
1287
1288/*
1289 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1290 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1291 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1292 */
1293static void sock_copy(struct sock *nsk, const struct sock *osk)
1294{
 
1295#ifdef CONFIG_SECURITY_NETWORK
1296	void *sptr = nsk->sk_security;
1297#endif
1298	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1299
1300	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1301	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1302
1303#ifdef CONFIG_SECURITY_NETWORK
1304	nsk->sk_security = sptr;
1305	security_sk_clone(osk, nsk);
1306#endif
1307}
1308
1309void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1310{
1311	unsigned long nulls1, nulls2;
1312
1313	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1314	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1315	if (nulls1 > nulls2)
1316		swap(nulls1, nulls2);
1317
1318	if (nulls1 != 0)
1319		memset((char *)sk, 0, nulls1);
1320	memset((char *)sk + nulls1 + sizeof(void *), 0,
1321	       nulls2 - nulls1 - sizeof(void *));
1322	memset((char *)sk + nulls2 + sizeof(void *), 0,
1323	       size - nulls2 - sizeof(void *));
1324}
1325EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1326
1327static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1328		int family)
1329{
1330	struct sock *sk;
1331	struct kmem_cache *slab;
1332
1333	slab = prot->slab;
1334	if (slab != NULL) {
1335		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1336		if (!sk)
1337			return sk;
1338		if (priority & __GFP_ZERO) {
1339			if (prot->clear_sk)
1340				prot->clear_sk(sk, prot->obj_size);
1341			else
1342				sk_prot_clear_nulls(sk, prot->obj_size);
1343		}
1344	} else
1345		sk = kmalloc(prot->obj_size, priority);
1346
1347	if (sk != NULL) {
1348		kmemcheck_annotate_bitfield(sk, flags);
1349
1350		if (security_sk_alloc(sk, family, priority))
1351			goto out_free;
1352
1353		if (!try_module_get(prot->owner))
1354			goto out_free_sec;
1355		sk_tx_queue_clear(sk);
1356		cgroup_sk_alloc(&sk->sk_cgrp_data);
1357	}
1358
1359	return sk;
1360
1361out_free_sec:
1362	security_sk_free(sk);
1363out_free:
1364	if (slab != NULL)
1365		kmem_cache_free(slab, sk);
1366	else
1367		kfree(sk);
1368	return NULL;
1369}
1370
1371static void sk_prot_free(struct proto *prot, struct sock *sk)
1372{
1373	struct kmem_cache *slab;
1374	struct module *owner;
1375
1376	owner = prot->owner;
1377	slab = prot->slab;
1378
1379	cgroup_sk_free(&sk->sk_cgrp_data);
 
1380	security_sk_free(sk);
1381	if (slab != NULL)
1382		kmem_cache_free(slab, sk);
1383	else
1384		kfree(sk);
1385	module_put(owner);
1386}
1387
1388/**
1389 *	sk_alloc - All socket objects are allocated here
1390 *	@net: the applicable net namespace
1391 *	@family: protocol family
1392 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1393 *	@prot: struct proto associated with this new sock instance
1394 *	@kern: is this to be a kernel socket?
1395 */
1396struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1397		      struct proto *prot, int kern)
1398{
1399	struct sock *sk;
1400
1401	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1402	if (sk) {
1403		sk->sk_family = family;
1404		/*
1405		 * See comment in struct sock definition to understand
1406		 * why we need sk_prot_creator -acme
1407		 */
1408		sk->sk_prot = sk->sk_prot_creator = prot;
 
1409		sock_lock_init(sk);
1410		sk->sk_net_refcnt = kern ? 0 : 1;
1411		if (likely(sk->sk_net_refcnt))
1412			get_net(net);
 
 
 
1413		sock_net_set(sk, net);
1414		atomic_set(&sk->sk_wmem_alloc, 1);
1415
 
 
1416		sock_update_classid(&sk->sk_cgrp_data);
1417		sock_update_netprioidx(&sk->sk_cgrp_data);
 
1418	}
1419
1420	return sk;
1421}
1422EXPORT_SYMBOL(sk_alloc);
1423
1424void sk_destruct(struct sock *sk)
 
 
 
1425{
 
1426	struct sk_filter *filter;
1427
1428	if (sk->sk_destruct)
1429		sk->sk_destruct(sk);
1430
1431	filter = rcu_dereference_check(sk->sk_filter,
1432				       atomic_read(&sk->sk_wmem_alloc) == 0);
1433	if (filter) {
1434		sk_filter_uncharge(sk, filter);
1435		RCU_INIT_POINTER(sk->sk_filter, NULL);
1436	}
1437	if (rcu_access_pointer(sk->sk_reuseport_cb))
1438		reuseport_detach_sock(sk);
1439
1440	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1441
 
 
 
 
1442	if (atomic_read(&sk->sk_omem_alloc))
1443		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1444			 __func__, atomic_read(&sk->sk_omem_alloc));
1445
 
 
 
 
 
1446	if (sk->sk_peer_cred)
1447		put_cred(sk->sk_peer_cred);
1448	put_pid(sk->sk_peer_pid);
1449	if (likely(sk->sk_net_refcnt))
1450		put_net(sock_net(sk));
1451	sk_prot_free(sk->sk_prot_creator, sk);
1452}
1453
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1454static void __sk_free(struct sock *sk)
1455{
1456	if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
 
 
 
1457		sock_diag_broadcast_destroy(sk);
1458	else
1459		sk_destruct(sk);
1460}
1461
1462void sk_free(struct sock *sk)
1463{
1464	/*
1465	 * We subtract one from sk_wmem_alloc and can know if
1466	 * some packets are still in some tx queue.
1467	 * If not null, sock_wfree() will call __sk_free(sk) later
1468	 */
1469	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1470		__sk_free(sk);
1471}
1472EXPORT_SYMBOL(sk_free);
1473
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1474/**
1475 *	sk_clone_lock - clone a socket, and lock its clone
1476 *	@sk: the socket to clone
1477 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1478 *
1479 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1480 */
1481struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1482{
 
1483	struct sock *newsk;
1484	bool is_charged = true;
1485
1486	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1487	if (newsk != NULL) {
1488		struct sk_filter *filter;
1489
1490		sock_copy(newsk, sk);
1491
 
 
1492		/* SANITY */
1493		if (likely(newsk->sk_net_refcnt))
1494			get_net(sock_net(newsk));
1495		sk_node_init(&newsk->sk_node);
1496		sock_lock_init(newsk);
1497		bh_lock_sock(newsk);
1498		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1499		newsk->sk_backlog.len = 0;
1500
1501		atomic_set(&newsk->sk_rmem_alloc, 0);
1502		/*
1503		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1504		 */
1505		atomic_set(&newsk->sk_wmem_alloc, 1);
1506		atomic_set(&newsk->sk_omem_alloc, 0);
1507		skb_queue_head_init(&newsk->sk_receive_queue);
1508		skb_queue_head_init(&newsk->sk_write_queue);
1509
1510		rwlock_init(&newsk->sk_callback_lock);
1511		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1512				af_callback_keys + newsk->sk_family,
1513				af_family_clock_key_strings[newsk->sk_family]);
1514
1515		newsk->sk_dst_cache	= NULL;
 
1516		newsk->sk_wmem_queued	= 0;
1517		newsk->sk_forward_alloc = 0;
 
1518		newsk->sk_send_head	= NULL;
1519		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
 
1520
1521		sock_reset_flag(newsk, SOCK_DONE);
1522		skb_queue_head_init(&newsk->sk_error_queue);
1523
1524		filter = rcu_dereference_protected(newsk->sk_filter, 1);
 
 
 
 
 
 
1525		if (filter != NULL)
1526			/* though it's an empty new sock, the charging may fail
1527			 * if sysctl_optmem_max was changed between creation of
1528			 * original socket and cloning
1529			 */
1530			is_charged = sk_filter_charge(newsk, filter);
 
 
1531
1532		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1533			/* It is still raw copy of parent, so invalidate
1534			 * destructor and make plain sk_free() */
1535			newsk->sk_destruct = NULL;
1536			bh_unlock_sock(newsk);
1537			sk_free(newsk);
 
 
1538			newsk = NULL;
1539			goto out;
1540		}
1541		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1542
 
 
 
 
 
 
 
 
 
 
 
 
1543		newsk->sk_err	   = 0;
 
1544		newsk->sk_priority = 0;
1545		newsk->sk_incoming_cpu = raw_smp_processor_id();
1546		atomic64_set(&newsk->sk_cookie, 0);
 
 
1547		/*
1548		 * Before updating sk_refcnt, we must commit prior changes to memory
1549		 * (Documentation/RCU/rculist_nulls.txt for details)
1550		 */
1551		smp_wmb();
1552		atomic_set(&newsk->sk_refcnt, 2);
1553
1554		/*
1555		 * Increment the counter in the same struct proto as the master
1556		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1557		 * is the same as sk->sk_prot->socks, as this field was copied
1558		 * with memcpy).
1559		 *
1560		 * This _changes_ the previous behaviour, where
1561		 * tcp_create_openreq_child always was incrementing the
1562		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1563		 * to be taken into account in all callers. -acme
1564		 */
1565		sk_refcnt_debug_inc(newsk);
1566		sk_set_socket(newsk, NULL);
1567		newsk->sk_wq = NULL;
1568
1569		if (mem_cgroup_sockets_enabled && sk->sk_memcg)
1570			sock_update_memcg(newsk);
1571
1572		if (newsk->sk_prot->sockets_allocated)
1573			sk_sockets_allocated_inc(newsk);
1574
1575		if (sock_needs_netstamp(sk) &&
1576		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1577			net_enable_timestamp();
1578	}
1579out:
1580	return newsk;
1581}
1582EXPORT_SYMBOL_GPL(sk_clone_lock);
1583
 
 
 
 
 
 
 
 
 
 
1584void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1585{
1586	u32 max_segs = 1;
1587
1588	sk_dst_set(sk, dst);
1589	sk->sk_route_caps = dst->dev->features;
1590	if (sk->sk_route_caps & NETIF_F_GSO)
1591		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1592	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1593	if (sk_can_gso(sk)) {
1594		if (dst->header_len) {
1595			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1596		} else {
1597			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1598			sk->sk_gso_max_size = dst->dev->gso_max_size;
1599			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1600		}
1601	}
1602	sk->sk_gso_max_segs = max_segs;
1603}
1604EXPORT_SYMBOL_GPL(sk_setup_caps);
1605
1606/*
1607 *	Simple resource managers for sockets.
1608 */
1609
1610
1611/*
1612 * Write buffer destructor automatically called from kfree_skb.
1613 */
1614void sock_wfree(struct sk_buff *skb)
1615{
1616	struct sock *sk = skb->sk;
1617	unsigned int len = skb->truesize;
1618
1619	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1620		/*
1621		 * Keep a reference on sk_wmem_alloc, this will be released
1622		 * after sk_write_space() call
1623		 */
1624		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1625		sk->sk_write_space(sk);
1626		len = 1;
1627	}
1628	/*
1629	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1630	 * could not do because of in-flight packets
1631	 */
1632	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1633		__sk_free(sk);
1634}
1635EXPORT_SYMBOL(sock_wfree);
1636
 
 
 
 
 
 
 
 
 
 
 
1637void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1638{
1639	skb_orphan(skb);
1640	skb->sk = sk;
1641#ifdef CONFIG_INET
1642	if (unlikely(!sk_fullsock(sk))) {
1643		skb->destructor = sock_edemux;
1644		sock_hold(sk);
1645		return;
1646	}
1647#endif
1648	skb->destructor = sock_wfree;
1649	skb_set_hash_from_sk(skb, sk);
1650	/*
1651	 * We used to take a refcount on sk, but following operation
1652	 * is enough to guarantee sk_free() wont free this sock until
1653	 * all in-flight packets are completed
1654	 */
1655	atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1656}
1657EXPORT_SYMBOL(skb_set_owner_w);
1658
1659void skb_orphan_partial(struct sk_buff *skb)
1660{
1661	/* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1662	 * so we do not completely orphan skb, but transfert all
1663	 * accounted bytes but one, to avoid unexpected reorders.
1664	 */
1665	if (skb->destructor == sock_wfree
1666#ifdef CONFIG_INET
1667	    || skb->destructor == tcp_wfree
1668#endif
1669		) {
1670		atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1671		skb->truesize = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1672	} else {
1673		skb_orphan(skb);
1674	}
1675}
1676EXPORT_SYMBOL(skb_orphan_partial);
1677
1678/*
1679 * Read buffer destructor automatically called from kfree_skb.
1680 */
1681void sock_rfree(struct sk_buff *skb)
1682{
1683	struct sock *sk = skb->sk;
1684	unsigned int len = skb->truesize;
1685
1686	atomic_sub(len, &sk->sk_rmem_alloc);
1687	sk_mem_uncharge(sk, len);
1688}
1689EXPORT_SYMBOL(sock_rfree);
1690
1691/*
1692 * Buffer destructor for skbs that are not used directly in read or write
1693 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1694 */
1695void sock_efree(struct sk_buff *skb)
1696{
1697	sock_put(skb->sk);
1698}
1699EXPORT_SYMBOL(sock_efree);
1700
 
 
 
 
 
 
 
 
 
 
 
 
1701kuid_t sock_i_uid(struct sock *sk)
1702{
1703	kuid_t uid;
1704
1705	read_lock_bh(&sk->sk_callback_lock);
1706	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1707	read_unlock_bh(&sk->sk_callback_lock);
1708	return uid;
1709}
1710EXPORT_SYMBOL(sock_i_uid);
1711
1712unsigned long sock_i_ino(struct sock *sk)
1713{
1714	unsigned long ino;
1715
1716	read_lock_bh(&sk->sk_callback_lock);
1717	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1718	read_unlock_bh(&sk->sk_callback_lock);
1719	return ino;
1720}
1721EXPORT_SYMBOL(sock_i_ino);
1722
1723/*
1724 * Allocate a skb from the socket's send buffer.
1725 */
1726struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1727			     gfp_t priority)
1728{
1729	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
 
1730		struct sk_buff *skb = alloc_skb(size, priority);
 
1731		if (skb) {
1732			skb_set_owner_w(skb, sk);
1733			return skb;
1734		}
1735	}
1736	return NULL;
1737}
1738EXPORT_SYMBOL(sock_wmalloc);
1739
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1740/*
1741 * Allocate a memory block from the socket's option memory buffer.
1742 */
1743void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1744{
1745	if ((unsigned int)size <= sysctl_optmem_max &&
1746	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1747		void *mem;
1748		/* First do the add, to avoid the race if kmalloc
1749		 * might sleep.
1750		 */
1751		atomic_add(size, &sk->sk_omem_alloc);
1752		mem = kmalloc(size, priority);
1753		if (mem)
1754			return mem;
1755		atomic_sub(size, &sk->sk_omem_alloc);
1756	}
1757	return NULL;
1758}
1759EXPORT_SYMBOL(sock_kmalloc);
1760
1761/* Free an option memory block. Note, we actually want the inline
1762 * here as this allows gcc to detect the nullify and fold away the
1763 * condition entirely.
1764 */
1765static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1766				  const bool nullify)
1767{
1768	if (WARN_ON_ONCE(!mem))
1769		return;
1770	if (nullify)
1771		kzfree(mem);
1772	else
1773		kfree(mem);
1774	atomic_sub(size, &sk->sk_omem_alloc);
1775}
1776
1777void sock_kfree_s(struct sock *sk, void *mem, int size)
1778{
1779	__sock_kfree_s(sk, mem, size, false);
1780}
1781EXPORT_SYMBOL(sock_kfree_s);
1782
1783void sock_kzfree_s(struct sock *sk, void *mem, int size)
1784{
1785	__sock_kfree_s(sk, mem, size, true);
1786}
1787EXPORT_SYMBOL(sock_kzfree_s);
1788
1789/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1790   I think, these locks should be removed for datagram sockets.
1791 */
1792static long sock_wait_for_wmem(struct sock *sk, long timeo)
1793{
1794	DEFINE_WAIT(wait);
1795
1796	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1797	for (;;) {
1798		if (!timeo)
1799			break;
1800		if (signal_pending(current))
1801			break;
1802		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1803		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1804		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1805			break;
1806		if (sk->sk_shutdown & SEND_SHUTDOWN)
1807			break;
1808		if (sk->sk_err)
1809			break;
1810		timeo = schedule_timeout(timeo);
1811	}
1812	finish_wait(sk_sleep(sk), &wait);
1813	return timeo;
1814}
1815
1816
1817/*
1818 *	Generic send/receive buffer handlers
1819 */
1820
1821struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1822				     unsigned long data_len, int noblock,
1823				     int *errcode, int max_page_order)
1824{
1825	struct sk_buff *skb;
1826	long timeo;
1827	int err;
1828
1829	timeo = sock_sndtimeo(sk, noblock);
1830	for (;;) {
1831		err = sock_error(sk);
1832		if (err != 0)
1833			goto failure;
1834
1835		err = -EPIPE;
1836		if (sk->sk_shutdown & SEND_SHUTDOWN)
1837			goto failure;
1838
1839		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1840			break;
1841
1842		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1843		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1844		err = -EAGAIN;
1845		if (!timeo)
1846			goto failure;
1847		if (signal_pending(current))
1848			goto interrupted;
1849		timeo = sock_wait_for_wmem(sk, timeo);
1850	}
1851	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1852				   errcode, sk->sk_allocation);
1853	if (skb)
1854		skb_set_owner_w(skb, sk);
1855	return skb;
1856
1857interrupted:
1858	err = sock_intr_errno(timeo);
1859failure:
1860	*errcode = err;
1861	return NULL;
1862}
1863EXPORT_SYMBOL(sock_alloc_send_pskb);
1864
1865struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1866				    int noblock, int *errcode)
1867{
1868	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1869}
1870EXPORT_SYMBOL(sock_alloc_send_skb);
1871
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1872int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1873		   struct sockcm_cookie *sockc)
1874{
1875	struct cmsghdr *cmsg;
 
1876
1877	for_each_cmsghdr(cmsg, msg) {
1878		if (!CMSG_OK(msg, cmsg))
1879			return -EINVAL;
1880		if (cmsg->cmsg_level != SOL_SOCKET)
1881			continue;
1882		switch (cmsg->cmsg_type) {
1883		case SO_MARK:
1884			if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1885				return -EPERM;
1886			if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1887				return -EINVAL;
1888			sockc->mark = *(u32 *)CMSG_DATA(cmsg);
1889			break;
1890		default:
1891			return -EINVAL;
1892		}
1893	}
1894	return 0;
1895}
1896EXPORT_SYMBOL(sock_cmsg_send);
1897
1898/* On 32bit arches, an skb frag is limited to 2^15 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1899#define SKB_FRAG_PAGE_ORDER	get_order(32768)
 
1900
1901/**
1902 * skb_page_frag_refill - check that a page_frag contains enough room
1903 * @sz: minimum size of the fragment we want to get
1904 * @pfrag: pointer to page_frag
1905 * @gfp: priority for memory allocation
1906 *
1907 * Note: While this allocator tries to use high order pages, there is
1908 * no guarantee that allocations succeed. Therefore, @sz MUST be
1909 * less or equal than PAGE_SIZE.
1910 */
1911bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1912{
1913	if (pfrag->page) {
1914		if (page_ref_count(pfrag->page) == 1) {
1915			pfrag->offset = 0;
1916			return true;
1917		}
1918		if (pfrag->offset + sz <= pfrag->size)
1919			return true;
1920		put_page(pfrag->page);
1921	}
1922
1923	pfrag->offset = 0;
1924	if (SKB_FRAG_PAGE_ORDER) {
 
1925		/* Avoid direct reclaim but allow kswapd to wake */
1926		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
1927					  __GFP_COMP | __GFP_NOWARN |
1928					  __GFP_NORETRY,
1929					  SKB_FRAG_PAGE_ORDER);
1930		if (likely(pfrag->page)) {
1931			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1932			return true;
1933		}
1934	}
1935	pfrag->page = alloc_page(gfp);
1936	if (likely(pfrag->page)) {
1937		pfrag->size = PAGE_SIZE;
1938		return true;
1939	}
1940	return false;
1941}
1942EXPORT_SYMBOL(skb_page_frag_refill);
1943
1944bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1945{
1946	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1947		return true;
1948
1949	sk_enter_memory_pressure(sk);
1950	sk_stream_moderate_sndbuf(sk);
1951	return false;
1952}
1953EXPORT_SYMBOL(sk_page_frag_refill);
1954
1955static void __lock_sock(struct sock *sk)
1956	__releases(&sk->sk_lock.slock)
1957	__acquires(&sk->sk_lock.slock)
1958{
1959	DEFINE_WAIT(wait);
1960
1961	for (;;) {
1962		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1963					TASK_UNINTERRUPTIBLE);
1964		spin_unlock_bh(&sk->sk_lock.slock);
1965		schedule();
1966		spin_lock_bh(&sk->sk_lock.slock);
1967		if (!sock_owned_by_user(sk))
1968			break;
1969	}
1970	finish_wait(&sk->sk_lock.wq, &wait);
1971}
1972
1973static void __release_sock(struct sock *sk)
1974	__releases(&sk->sk_lock.slock)
1975	__acquires(&sk->sk_lock.slock)
1976{
1977	struct sk_buff *skb = sk->sk_backlog.head;
1978
1979	do {
1980		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1981		bh_unlock_sock(sk);
 
1982
1983		do {
1984			struct sk_buff *next = skb->next;
1985
1986			prefetch(next);
1987			WARN_ON_ONCE(skb_dst_is_noref(skb));
1988			skb->next = NULL;
1989			sk_backlog_rcv(sk, skb);
1990
1991			/*
1992			 * We are in process context here with softirqs
1993			 * disabled, use cond_resched_softirq() to preempt.
1994			 * This is safe to do because we've taken the backlog
1995			 * queue private:
1996			 */
1997			cond_resched_softirq();
1998
1999			skb = next;
2000		} while (skb != NULL);
2001
2002		bh_lock_sock(sk);
2003	} while ((skb = sk->sk_backlog.head) != NULL);
2004
2005	/*
2006	 * Doing the zeroing here guarantee we can not loop forever
2007	 * while a wild producer attempts to flood us.
2008	 */
2009	sk->sk_backlog.len = 0;
2010}
2011
 
 
 
 
 
 
 
2012/**
2013 * sk_wait_data - wait for data to arrive at sk_receive_queue
2014 * @sk:    sock to wait on
2015 * @timeo: for how long
2016 * @skb:   last skb seen on sk_receive_queue
2017 *
2018 * Now socket state including sk->sk_err is changed only under lock,
2019 * hence we may omit checks after joining wait queue.
2020 * We check receive queue before schedule() only as optimization;
2021 * it is very likely that release_sock() added new data.
2022 */
2023int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2024{
 
2025	int rc;
2026	DEFINE_WAIT(wait);
2027
2028	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2029	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2030	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb);
2031	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2032	finish_wait(sk_sleep(sk), &wait);
2033	return rc;
2034}
2035EXPORT_SYMBOL(sk_wait_data);
2036
2037/**
2038 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2039 *	@sk: socket
2040 *	@size: memory size to allocate
 
2041 *	@kind: allocation type
2042 *
2043 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2044 *	rmem allocation. This function assumes that protocols which have
2045 *	memory_pressure use sk_wmem_queued as write buffer accounting.
2046 */
2047int __sk_mem_schedule(struct sock *sk, int size, int kind)
2048{
2049	struct proto *prot = sk->sk_prot;
2050	int amt = sk_mem_pages(size);
2051	long allocated;
2052
2053	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2054
2055	allocated = sk_memory_allocated_add(sk, amt);
2056
2057	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2058	    !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2059		goto suppress_allocation;
2060
2061	/* Under limit. */
2062	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2063		sk_leave_memory_pressure(sk);
2064		return 1;
2065	}
2066
2067	/* Under pressure. */
2068	if (allocated > sk_prot_mem_limits(sk, 1))
2069		sk_enter_memory_pressure(sk);
2070
2071	/* Over hard limit. */
2072	if (allocated > sk_prot_mem_limits(sk, 2))
2073		goto suppress_allocation;
2074
2075	/* guarantee minimum buffer size under pressure */
2076	if (kind == SK_MEM_RECV) {
2077		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2078			return 1;
2079
2080	} else { /* SK_MEM_SEND */
 
 
2081		if (sk->sk_type == SOCK_STREAM) {
2082			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2083				return 1;
2084		} else if (atomic_read(&sk->sk_wmem_alloc) <
2085			   prot->sysctl_wmem[0])
2086				return 1;
 
2087	}
2088
2089	if (sk_has_memory_pressure(sk)) {
2090		int alloc;
2091
2092		if (!sk_under_memory_pressure(sk))
2093			return 1;
2094		alloc = sk_sockets_allocated_read_positive(sk);
2095		if (sk_prot_mem_limits(sk, 2) > alloc *
2096		    sk_mem_pages(sk->sk_wmem_queued +
2097				 atomic_read(&sk->sk_rmem_alloc) +
2098				 sk->sk_forward_alloc))
2099			return 1;
2100	}
2101
2102suppress_allocation:
2103
2104	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2105		sk_stream_moderate_sndbuf(sk);
2106
2107		/* Fail only if socket is _under_ its sndbuf.
2108		 * In this case we cannot block, so that we have to fail.
2109		 */
2110		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2111			return 1;
2112	}
2113
2114	trace_sock_exceed_buf_limit(sk, prot, allocated);
2115
2116	/* Alas. Undo changes. */
2117	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2118
2119	sk_memory_allocated_sub(sk, amt);
2120
2121	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2122		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2123
2124	return 0;
2125}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2126EXPORT_SYMBOL(__sk_mem_schedule);
2127
2128/**
2129 *	__sk_mem_reclaim - reclaim memory_allocated
2130 *	@sk: socket
2131 *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
 
 
2132 */
2133void __sk_mem_reclaim(struct sock *sk, int amount)
2134{
2135	amount >>= SK_MEM_QUANTUM_SHIFT;
2136	sk_memory_allocated_sub(sk, amount);
2137	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2138
2139	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2140		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2141
2142	if (sk_under_memory_pressure(sk) &&
2143	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2144		sk_leave_memory_pressure(sk);
2145}
 
 
 
 
 
 
 
 
 
 
 
 
 
2146EXPORT_SYMBOL(__sk_mem_reclaim);
2147
 
 
 
 
 
 
2148
2149/*
2150 * Set of default routines for initialising struct proto_ops when
2151 * the protocol does not support a particular function. In certain
2152 * cases where it makes no sense for a protocol to have a "do nothing"
2153 * function, some default processing is provided.
2154 */
2155
2156int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2157{
2158	return -EOPNOTSUPP;
2159}
2160EXPORT_SYMBOL(sock_no_bind);
2161
2162int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2163		    int len, int flags)
2164{
2165	return -EOPNOTSUPP;
2166}
2167EXPORT_SYMBOL(sock_no_connect);
2168
2169int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2170{
2171	return -EOPNOTSUPP;
2172}
2173EXPORT_SYMBOL(sock_no_socketpair);
2174
2175int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
 
2176{
2177	return -EOPNOTSUPP;
2178}
2179EXPORT_SYMBOL(sock_no_accept);
2180
2181int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2182		    int *len, int peer)
2183{
2184	return -EOPNOTSUPP;
2185}
2186EXPORT_SYMBOL(sock_no_getname);
2187
2188unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2189{
2190	return 0;
2191}
2192EXPORT_SYMBOL(sock_no_poll);
2193
2194int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2195{
2196	return -EOPNOTSUPP;
2197}
2198EXPORT_SYMBOL(sock_no_ioctl);
2199
2200int sock_no_listen(struct socket *sock, int backlog)
2201{
2202	return -EOPNOTSUPP;
2203}
2204EXPORT_SYMBOL(sock_no_listen);
2205
2206int sock_no_shutdown(struct socket *sock, int how)
2207{
2208	return -EOPNOTSUPP;
2209}
2210EXPORT_SYMBOL(sock_no_shutdown);
2211
2212int sock_no_setsockopt(struct socket *sock, int level, int optname,
2213		    char __user *optval, unsigned int optlen)
2214{
2215	return -EOPNOTSUPP;
2216}
2217EXPORT_SYMBOL(sock_no_setsockopt);
2218
2219int sock_no_getsockopt(struct socket *sock, int level, int optname,
2220		    char __user *optval, int __user *optlen)
2221{
2222	return -EOPNOTSUPP;
2223}
2224EXPORT_SYMBOL(sock_no_getsockopt);
2225
2226int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2227{
2228	return -EOPNOTSUPP;
2229}
2230EXPORT_SYMBOL(sock_no_sendmsg);
2231
2232int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2233		    int flags)
2234{
2235	return -EOPNOTSUPP;
2236}
2237EXPORT_SYMBOL(sock_no_recvmsg);
2238
2239int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2240{
2241	/* Mirror missing mmap method error code */
2242	return -ENODEV;
2243}
2244EXPORT_SYMBOL(sock_no_mmap);
2245
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2246ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2247{
2248	ssize_t res;
2249	struct msghdr msg = {.msg_flags = flags};
2250	struct kvec iov;
2251	char *kaddr = kmap(page);
2252	iov.iov_base = kaddr + offset;
2253	iov.iov_len = size;
2254	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2255	kunmap(page);
2256	return res;
2257}
2258EXPORT_SYMBOL(sock_no_sendpage);
2259
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2260/*
2261 *	Default Socket Callbacks
2262 */
2263
2264static void sock_def_wakeup(struct sock *sk)
2265{
2266	struct socket_wq *wq;
2267
2268	rcu_read_lock();
2269	wq = rcu_dereference(sk->sk_wq);
2270	if (skwq_has_sleeper(wq))
2271		wake_up_interruptible_all(&wq->wait);
2272	rcu_read_unlock();
2273}
2274
2275static void sock_def_error_report(struct sock *sk)
2276{
2277	struct socket_wq *wq;
2278
2279	rcu_read_lock();
2280	wq = rcu_dereference(sk->sk_wq);
2281	if (skwq_has_sleeper(wq))
2282		wake_up_interruptible_poll(&wq->wait, POLLERR);
2283	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2284	rcu_read_unlock();
2285}
2286
2287static void sock_def_readable(struct sock *sk)
2288{
2289	struct socket_wq *wq;
2290
2291	rcu_read_lock();
2292	wq = rcu_dereference(sk->sk_wq);
2293	if (skwq_has_sleeper(wq))
2294		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2295						POLLRDNORM | POLLRDBAND);
2296	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2297	rcu_read_unlock();
2298}
2299
2300static void sock_def_write_space(struct sock *sk)
2301{
2302	struct socket_wq *wq;
2303
2304	rcu_read_lock();
2305
2306	/* Do not wake up a writer until he can make "significant"
2307	 * progress.  --DaveM
2308	 */
2309	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2310		wq = rcu_dereference(sk->sk_wq);
2311		if (skwq_has_sleeper(wq))
2312			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2313						POLLWRNORM | POLLWRBAND);
2314
2315		/* Should agree with poll, otherwise some programs break */
2316		if (sock_writeable(sk))
2317			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2318	}
2319
2320	rcu_read_unlock();
2321}
2322
2323static void sock_def_destruct(struct sock *sk)
2324{
2325}
2326
2327void sk_send_sigurg(struct sock *sk)
2328{
2329	if (sk->sk_socket && sk->sk_socket->file)
2330		if (send_sigurg(&sk->sk_socket->file->f_owner))
2331			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2332}
2333EXPORT_SYMBOL(sk_send_sigurg);
2334
2335void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2336		    unsigned long expires)
2337{
2338	if (!mod_timer(timer, expires))
2339		sock_hold(sk);
2340}
2341EXPORT_SYMBOL(sk_reset_timer);
2342
2343void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2344{
2345	if (del_timer(timer))
2346		__sock_put(sk);
2347}
2348EXPORT_SYMBOL(sk_stop_timer);
2349
2350void sock_init_data(struct socket *sock, struct sock *sk)
2351{
2352	skb_queue_head_init(&sk->sk_receive_queue);
2353	skb_queue_head_init(&sk->sk_write_queue);
2354	skb_queue_head_init(&sk->sk_error_queue);
2355
2356	sk->sk_send_head	=	NULL;
2357
2358	init_timer(&sk->sk_timer);
2359
2360	sk->sk_allocation	=	GFP_KERNEL;
2361	sk->sk_rcvbuf		=	sysctl_rmem_default;
2362	sk->sk_sndbuf		=	sysctl_wmem_default;
2363	sk->sk_state		=	TCP_CLOSE;
2364	sk_set_socket(sk, sock);
2365
2366	sock_set_flag(sk, SOCK_ZAPPED);
2367
2368	if (sock) {
2369		sk->sk_type	=	sock->type;
2370		sk->sk_wq	=	sock->wq;
2371		sock->sk	=	sk;
2372	} else
2373		sk->sk_wq	=	NULL;
 
 
 
2374
2375	rwlock_init(&sk->sk_callback_lock);
2376	lockdep_set_class_and_name(&sk->sk_callback_lock,
 
 
 
 
 
 
 
2377			af_callback_keys + sk->sk_family,
2378			af_family_clock_key_strings[sk->sk_family]);
2379
2380	sk->sk_state_change	=	sock_def_wakeup;
2381	sk->sk_data_ready	=	sock_def_readable;
2382	sk->sk_write_space	=	sock_def_write_space;
2383	sk->sk_error_report	=	sock_def_error_report;
2384	sk->sk_destruct		=	sock_def_destruct;
2385
2386	sk->sk_frag.page	=	NULL;
2387	sk->sk_frag.offset	=	0;
2388	sk->sk_peek_off		=	-1;
2389
2390	sk->sk_peer_pid 	=	NULL;
2391	sk->sk_peer_cred	=	NULL;
2392	sk->sk_write_pending	=	0;
2393	sk->sk_rcvlowat		=	1;
2394	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2395	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2396
2397	sk->sk_stamp = ktime_set(-1L, 0);
 
 
 
 
2398
2399#ifdef CONFIG_NET_RX_BUSY_POLL
2400	sk->sk_napi_id		=	0;
2401	sk->sk_ll_usec		=	sysctl_net_busy_read;
2402#endif
2403
2404	sk->sk_max_pacing_rate = ~0U;
2405	sk->sk_pacing_rate = ~0U;
 
2406	sk->sk_incoming_cpu = -1;
 
 
2407	/*
2408	 * Before updating sk_refcnt, we must commit prior changes to memory
2409	 * (Documentation/RCU/rculist_nulls.txt for details)
2410	 */
2411	smp_wmb();
2412	atomic_set(&sk->sk_refcnt, 1);
2413	atomic_set(&sk->sk_drops, 0);
2414}
2415EXPORT_SYMBOL(sock_init_data);
2416
2417void lock_sock_nested(struct sock *sk, int subclass)
2418{
2419	might_sleep();
2420	spin_lock_bh(&sk->sk_lock.slock);
2421	if (sk->sk_lock.owned)
2422		__lock_sock(sk);
2423	sk->sk_lock.owned = 1;
2424	spin_unlock(&sk->sk_lock.slock);
2425	/*
2426	 * The sk_lock has mutex_lock() semantics here:
2427	 */
2428	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2429	local_bh_enable();
2430}
2431EXPORT_SYMBOL(lock_sock_nested);
2432
2433void release_sock(struct sock *sk)
2434{
2435	/*
2436	 * The sk_lock has mutex_unlock() semantics:
2437	 */
2438	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2439
2440	spin_lock_bh(&sk->sk_lock.slock);
2441	if (sk->sk_backlog.tail)
2442		__release_sock(sk);
2443
2444	/* Warning : release_cb() might need to release sk ownership,
2445	 * ie call sock_release_ownership(sk) before us.
2446	 */
2447	if (sk->sk_prot->release_cb)
2448		sk->sk_prot->release_cb(sk);
2449
2450	sock_release_ownership(sk);
2451	if (waitqueue_active(&sk->sk_lock.wq))
2452		wake_up(&sk->sk_lock.wq);
2453	spin_unlock_bh(&sk->sk_lock.slock);
2454}
2455EXPORT_SYMBOL(release_sock);
2456
2457/**
2458 * lock_sock_fast - fast version of lock_sock
2459 * @sk: socket
2460 *
2461 * This version should be used for very small section, where process wont block
2462 * return false if fast path is taken
 
2463 *   sk_lock.slock locked, owned = 0, BH disabled
2464 * return true if slow path is taken
 
 
2465 *   sk_lock.slock unlocked, owned = 1, BH enabled
2466 */
2467bool lock_sock_fast(struct sock *sk)
2468{
2469	might_sleep();
2470	spin_lock_bh(&sk->sk_lock.slock);
2471
2472	if (!sk->sk_lock.owned)
2473		/*
2474		 * Note : We must disable BH
2475		 */
2476		return false;
2477
2478	__lock_sock(sk);
2479	sk->sk_lock.owned = 1;
2480	spin_unlock(&sk->sk_lock.slock);
2481	/*
2482	 * The sk_lock has mutex_lock() semantics here:
2483	 */
2484	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2485	local_bh_enable();
2486	return true;
2487}
2488EXPORT_SYMBOL(lock_sock_fast);
2489
2490int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
 
2491{
2492	struct timeval tv;
2493	if (!sock_flag(sk, SOCK_TIMESTAMP))
2494		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2495	tv = ktime_to_timeval(sk->sk_stamp);
2496	if (tv.tv_sec == -1)
2497		return -ENOENT;
2498	if (tv.tv_sec == 0) {
2499		sk->sk_stamp = ktime_get_real();
2500		tv = ktime_to_timeval(sk->sk_stamp);
2501	}
2502	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2503}
2504EXPORT_SYMBOL(sock_get_timestamp);
2505
2506int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2507{
2508	struct timespec ts;
2509	if (!sock_flag(sk, SOCK_TIMESTAMP))
2510		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2511	ts = ktime_to_timespec(sk->sk_stamp);
2512	if (ts.tv_sec == -1)
2513		return -ENOENT;
2514	if (ts.tv_sec == 0) {
2515		sk->sk_stamp = ktime_get_real();
2516		ts = ktime_to_timespec(sk->sk_stamp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2517	}
2518	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
 
2519}
2520EXPORT_SYMBOL(sock_get_timestampns);
2521
2522void sock_enable_timestamp(struct sock *sk, int flag)
2523{
2524	if (!sock_flag(sk, flag)) {
2525		unsigned long previous_flags = sk->sk_flags;
2526
2527		sock_set_flag(sk, flag);
2528		/*
2529		 * we just set one of the two flags which require net
2530		 * time stamping, but time stamping might have been on
2531		 * already because of the other one
2532		 */
2533		if (sock_needs_netstamp(sk) &&
2534		    !(previous_flags & SK_FLAGS_TIMESTAMP))
2535			net_enable_timestamp();
2536	}
2537}
2538
2539int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2540		       int level, int type)
2541{
2542	struct sock_exterr_skb *serr;
2543	struct sk_buff *skb;
2544	int copied, err;
2545
2546	err = -EAGAIN;
2547	skb = sock_dequeue_err_skb(sk);
2548	if (skb == NULL)
2549		goto out;
2550
2551	copied = skb->len;
2552	if (copied > len) {
2553		msg->msg_flags |= MSG_TRUNC;
2554		copied = len;
2555	}
2556	err = skb_copy_datagram_msg(skb, 0, msg, copied);
2557	if (err)
2558		goto out_free_skb;
2559
2560	sock_recv_timestamp(msg, sk, skb);
2561
2562	serr = SKB_EXT_ERR(skb);
2563	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2564
2565	msg->msg_flags |= MSG_ERRQUEUE;
2566	err = copied;
2567
2568out_free_skb:
2569	kfree_skb(skb);
2570out:
2571	return err;
2572}
2573EXPORT_SYMBOL(sock_recv_errqueue);
2574
2575/*
2576 *	Get a socket option on an socket.
2577 *
2578 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2579 *	asynchronous errors should be reported by getsockopt. We assume
2580 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2581 */
2582int sock_common_getsockopt(struct socket *sock, int level, int optname,
2583			   char __user *optval, int __user *optlen)
2584{
2585	struct sock *sk = sock->sk;
2586
2587	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2588}
2589EXPORT_SYMBOL(sock_common_getsockopt);
2590
2591#ifdef CONFIG_COMPAT
2592int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2593				  char __user *optval, int __user *optlen)
2594{
2595	struct sock *sk = sock->sk;
2596
2597	if (sk->sk_prot->compat_getsockopt != NULL)
2598		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2599						      optval, optlen);
2600	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2601}
2602EXPORT_SYMBOL(compat_sock_common_getsockopt);
2603#endif
2604
2605int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2606			int flags)
2607{
2608	struct sock *sk = sock->sk;
2609	int addr_len = 0;
2610	int err;
2611
2612	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2613				   flags & ~MSG_DONTWAIT, &addr_len);
2614	if (err >= 0)
2615		msg->msg_namelen = addr_len;
2616	return err;
2617}
2618EXPORT_SYMBOL(sock_common_recvmsg);
2619
2620/*
2621 *	Set socket options on an inet socket.
2622 */
2623int sock_common_setsockopt(struct socket *sock, int level, int optname,
2624			   char __user *optval, unsigned int optlen)
2625{
2626	struct sock *sk = sock->sk;
2627
2628	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2629}
2630EXPORT_SYMBOL(sock_common_setsockopt);
2631
2632#ifdef CONFIG_COMPAT
2633int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2634				  char __user *optval, unsigned int optlen)
2635{
2636	struct sock *sk = sock->sk;
2637
2638	if (sk->sk_prot->compat_setsockopt != NULL)
2639		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2640						      optval, optlen);
2641	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2642}
2643EXPORT_SYMBOL(compat_sock_common_setsockopt);
2644#endif
2645
2646void sk_common_release(struct sock *sk)
2647{
2648	if (sk->sk_prot->destroy)
2649		sk->sk_prot->destroy(sk);
2650
2651	/*
2652	 * Observation: when sock_common_release is called, processes have
2653	 * no access to socket. But net still has.
2654	 * Step one, detach it from networking:
2655	 *
2656	 * A. Remove from hash tables.
2657	 */
2658
2659	sk->sk_prot->unhash(sk);
2660
2661	/*
2662	 * In this point socket cannot receive new packets, but it is possible
2663	 * that some packets are in flight because some CPU runs receiver and
2664	 * did hash table lookup before we unhashed socket. They will achieve
2665	 * receive queue and will be purged by socket destructor.
2666	 *
2667	 * Also we still have packets pending on receive queue and probably,
2668	 * our own packets waiting in device queues. sock_destroy will drain
2669	 * receive queue, but transmitted packets will delay socket destruction
2670	 * until the last reference will be released.
2671	 */
2672
2673	sock_orphan(sk);
2674
2675	xfrm_sk_free_policy(sk);
2676
2677	sk_refcnt_debug_release(sk);
2678
2679	if (sk->sk_frag.page) {
2680		put_page(sk->sk_frag.page);
2681		sk->sk_frag.page = NULL;
2682	}
2683
2684	sock_put(sk);
2685}
2686EXPORT_SYMBOL(sk_common_release);
2687
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2688#ifdef CONFIG_PROC_FS
2689#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2690struct prot_inuse {
2691	int val[PROTO_INUSE_NR];
2692};
2693
2694static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2695
2696#ifdef CONFIG_NET_NS
2697void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2698{
2699	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2700}
2701EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2702
2703int sock_prot_inuse_get(struct net *net, struct proto *prot)
2704{
2705	int cpu, idx = prot->inuse_idx;
2706	int res = 0;
2707
2708	for_each_possible_cpu(cpu)
2709		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2710
2711	return res >= 0 ? res : 0;
2712}
2713EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2714
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2715static int __net_init sock_inuse_init_net(struct net *net)
2716{
2717	net->core.inuse = alloc_percpu(struct prot_inuse);
2718	return net->core.inuse ? 0 : -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
2719}
2720
2721static void __net_exit sock_inuse_exit_net(struct net *net)
2722{
2723	free_percpu(net->core.inuse);
 
2724}
2725
2726static struct pernet_operations net_inuse_ops = {
2727	.init = sock_inuse_init_net,
2728	.exit = sock_inuse_exit_net,
2729};
2730
2731static __init int net_inuse_init(void)
2732{
2733	if (register_pernet_subsys(&net_inuse_ops))
2734		panic("Cannot initialize net inuse counters");
2735
2736	return 0;
2737}
2738
2739core_initcall(net_inuse_init);
2740#else
2741static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2742
2743void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2744{
2745	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2746}
2747EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2748
2749int sock_prot_inuse_get(struct net *net, struct proto *prot)
2750{
2751	int cpu, idx = prot->inuse_idx;
2752	int res = 0;
2753
2754	for_each_possible_cpu(cpu)
2755		res += per_cpu(prot_inuse, cpu).val[idx];
2756
2757	return res >= 0 ? res : 0;
2758}
2759EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2760#endif
2761
2762static void assign_proto_idx(struct proto *prot)
2763{
2764	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2765
2766	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2767		pr_err("PROTO_INUSE_NR exhausted\n");
2768		return;
2769	}
2770
2771	set_bit(prot->inuse_idx, proto_inuse_idx);
 
2772}
2773
2774static void release_proto_idx(struct proto *prot)
2775{
2776	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2777		clear_bit(prot->inuse_idx, proto_inuse_idx);
2778}
2779#else
2780static inline void assign_proto_idx(struct proto *prot)
2781{
 
2782}
2783
2784static inline void release_proto_idx(struct proto *prot)
2785{
2786}
 
 
 
 
2787#endif
2788
 
 
 
 
 
 
 
 
 
 
2789static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2790{
2791	if (!rsk_prot)
2792		return;
2793	kfree(rsk_prot->slab_name);
2794	rsk_prot->slab_name = NULL;
2795	kmem_cache_destroy(rsk_prot->slab);
2796	rsk_prot->slab = NULL;
2797}
2798
2799static int req_prot_init(const struct proto *prot)
2800{
2801	struct request_sock_ops *rsk_prot = prot->rsk_prot;
2802
2803	if (!rsk_prot)
2804		return 0;
2805
2806	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2807					prot->name);
2808	if (!rsk_prot->slab_name)
2809		return -ENOMEM;
2810
2811	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2812					   rsk_prot->obj_size, 0,
2813					   prot->slab_flags, NULL);
 
2814
2815	if (!rsk_prot->slab) {
2816		pr_crit("%s: Can't create request sock SLAB cache!\n",
2817			prot->name);
2818		return -ENOMEM;
2819	}
2820	return 0;
2821}
2822
2823int proto_register(struct proto *prot, int alloc_slab)
2824{
 
 
2825	if (alloc_slab) {
2826		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2827					SLAB_HWCACHE_ALIGN | prot->slab_flags,
 
 
 
2828					NULL);
2829
2830		if (prot->slab == NULL) {
2831			pr_crit("%s: Can't create sock SLAB cache!\n",
2832				prot->name);
2833			goto out;
2834		}
2835
2836		if (req_prot_init(prot))
2837			goto out_free_request_sock_slab;
2838
2839		if (prot->twsk_prot != NULL) {
2840			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2841
2842			if (prot->twsk_prot->twsk_slab_name == NULL)
2843				goto out_free_request_sock_slab;
2844
2845			prot->twsk_prot->twsk_slab =
2846				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2847						  prot->twsk_prot->twsk_obj_size,
2848						  0,
 
2849						  prot->slab_flags,
2850						  NULL);
2851			if (prot->twsk_prot->twsk_slab == NULL)
2852				goto out_free_timewait_sock_slab_name;
2853		}
2854	}
2855
2856	mutex_lock(&proto_list_mutex);
 
 
 
 
 
2857	list_add(&prot->node, &proto_list);
2858	assign_proto_idx(prot);
2859	mutex_unlock(&proto_list_mutex);
2860	return 0;
2861
2862out_free_timewait_sock_slab_name:
2863	kfree(prot->twsk_prot->twsk_slab_name);
 
2864out_free_request_sock_slab:
2865	req_prot_cleanup(prot->rsk_prot);
 
2866
2867	kmem_cache_destroy(prot->slab);
2868	prot->slab = NULL;
 
2869out:
2870	return -ENOBUFS;
2871}
2872EXPORT_SYMBOL(proto_register);
2873
2874void proto_unregister(struct proto *prot)
2875{
2876	mutex_lock(&proto_list_mutex);
2877	release_proto_idx(prot);
2878	list_del(&prot->node);
2879	mutex_unlock(&proto_list_mutex);
2880
2881	kmem_cache_destroy(prot->slab);
2882	prot->slab = NULL;
2883
2884	req_prot_cleanup(prot->rsk_prot);
 
 
 
 
 
 
 
 
 
2885
2886	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2887		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2888		kfree(prot->twsk_prot->twsk_slab_name);
2889		prot->twsk_prot->twsk_slab = NULL;
2890	}
 
 
 
 
 
 
 
 
 
 
 
2891}
2892EXPORT_SYMBOL(proto_unregister);
2893
2894#ifdef CONFIG_PROC_FS
2895static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2896	__acquires(proto_list_mutex)
2897{
2898	mutex_lock(&proto_list_mutex);
2899	return seq_list_start_head(&proto_list, *pos);
2900}
2901
2902static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2903{
2904	return seq_list_next(v, &proto_list, pos);
2905}
2906
2907static void proto_seq_stop(struct seq_file *seq, void *v)
2908	__releases(proto_list_mutex)
2909{
2910	mutex_unlock(&proto_list_mutex);
2911}
2912
2913static char proto_method_implemented(const void *method)
2914{
2915	return method == NULL ? 'n' : 'y';
2916}
2917static long sock_prot_memory_allocated(struct proto *proto)
2918{
2919	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2920}
2921
2922static char *sock_prot_memory_pressure(struct proto *proto)
2923{
2924	return proto->memory_pressure != NULL ?
2925	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2926}
2927
2928static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2929{
2930
2931	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2932			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2933		   proto->name,
2934		   proto->obj_size,
2935		   sock_prot_inuse_get(seq_file_net(seq), proto),
2936		   sock_prot_memory_allocated(proto),
2937		   sock_prot_memory_pressure(proto),
2938		   proto->max_header,
2939		   proto->slab == NULL ? "no" : "yes",
2940		   module_name(proto->owner),
2941		   proto_method_implemented(proto->close),
2942		   proto_method_implemented(proto->connect),
2943		   proto_method_implemented(proto->disconnect),
2944		   proto_method_implemented(proto->accept),
2945		   proto_method_implemented(proto->ioctl),
2946		   proto_method_implemented(proto->init),
2947		   proto_method_implemented(proto->destroy),
2948		   proto_method_implemented(proto->shutdown),
2949		   proto_method_implemented(proto->setsockopt),
2950		   proto_method_implemented(proto->getsockopt),
2951		   proto_method_implemented(proto->sendmsg),
2952		   proto_method_implemented(proto->recvmsg),
2953		   proto_method_implemented(proto->sendpage),
2954		   proto_method_implemented(proto->bind),
2955		   proto_method_implemented(proto->backlog_rcv),
2956		   proto_method_implemented(proto->hash),
2957		   proto_method_implemented(proto->unhash),
2958		   proto_method_implemented(proto->get_port),
2959		   proto_method_implemented(proto->enter_memory_pressure));
2960}
2961
2962static int proto_seq_show(struct seq_file *seq, void *v)
2963{
2964	if (v == &proto_list)
2965		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2966			   "protocol",
2967			   "size",
2968			   "sockets",
2969			   "memory",
2970			   "press",
2971			   "maxhdr",
2972			   "slab",
2973			   "module",
2974			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2975	else
2976		proto_seq_printf(seq, list_entry(v, struct proto, node));
2977	return 0;
2978}
2979
2980static const struct seq_operations proto_seq_ops = {
2981	.start  = proto_seq_start,
2982	.next   = proto_seq_next,
2983	.stop   = proto_seq_stop,
2984	.show   = proto_seq_show,
2985};
2986
2987static int proto_seq_open(struct inode *inode, struct file *file)
2988{
2989	return seq_open_net(inode, file, &proto_seq_ops,
2990			    sizeof(struct seq_net_private));
2991}
2992
2993static const struct file_operations proto_seq_fops = {
2994	.owner		= THIS_MODULE,
2995	.open		= proto_seq_open,
2996	.read		= seq_read,
2997	.llseek		= seq_lseek,
2998	.release	= seq_release_net,
2999};
3000
3001static __net_init int proto_init_net(struct net *net)
3002{
3003	if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
 
3004		return -ENOMEM;
3005
3006	return 0;
3007}
3008
3009static __net_exit void proto_exit_net(struct net *net)
3010{
3011	remove_proc_entry("protocols", net->proc_net);
3012}
3013
3014
3015static __net_initdata struct pernet_operations proto_net_ops = {
3016	.init = proto_init_net,
3017	.exit = proto_exit_net,
3018};
3019
3020static int __init proto_init(void)
3021{
3022	return register_pernet_subsys(&proto_net_ops);
3023}
3024
3025subsys_initcall(proto_init);
3026
3027#endif /* PROC_FS */