xref: /linux/net/core/sock.c (revision 4d6575949d914c5fb8ec2d6ca3a706f9a2b434b7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <linux/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/udp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 #include <linux/static_key.h>
115 #include <linux/memcontrol.h>
116 #include <linux/prefetch.h>
117 #include <linux/compat.h>
118 #include <linux/mroute.h>
119 #include <linux/mroute6.h>
120 #include <linux/icmpv6.h>
121 
122 #include <linux/uaccess.h>
123 
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <linux/skbuff_ref.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <net/proto_memory.h>
132 #include <linux/net_tstamp.h>
133 #include <net/xfrm.h>
134 #include <linux/ipsec.h>
135 #include <net/cls_cgroup.h>
136 #include <net/netprio_cgroup.h>
137 #include <linux/sock_diag.h>
138 
139 #include <linux/filter.h>
140 #include <net/sock_reuseport.h>
141 #include <net/bpf_sk_storage.h>
142 
143 #include <trace/events/sock.h>
144 
145 #include <net/tcp.h>
146 #include <net/busy_poll.h>
147 #include <net/phonet/phonet.h>
148 
149 #include <linux/ethtool.h>
150 
151 #include <uapi/linux/pidfd.h>
152 
153 #include "dev.h"
154 
155 static DEFINE_MUTEX(proto_list_mutex);
156 static LIST_HEAD(proto_list);
157 
158 static void sock_def_write_space_wfree(struct sock *sk);
159 static void sock_def_write_space(struct sock *sk);
160 
161 /**
162  * sk_ns_capable - General socket capability test
163  * @sk: Socket to use a capability on or through
164  * @user_ns: The user namespace of the capability to use
165  * @cap: The capability to use
166  *
167  * Test to see if the opener of the socket had when the socket was
168  * created and the current process has the capability @cap in the user
169  * namespace @user_ns.
170  */
171 bool sk_ns_capable(const struct sock *sk,
172 		   struct user_namespace *user_ns, int cap)
173 {
174 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
175 		ns_capable(user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_ns_capable);
178 
179 /**
180  * sk_capable - Socket global capability test
181  * @sk: Socket to use a capability on or through
182  * @cap: The global capability to use
183  *
184  * Test to see if the opener of the socket had when the socket was
185  * created and the current process has the capability @cap in all user
186  * namespaces.
187  */
188 bool sk_capable(const struct sock *sk, int cap)
189 {
190 	return sk_ns_capable(sk, &init_user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_capable);
193 
194 /**
195  * sk_net_capable - Network namespace socket capability test
196  * @sk: Socket to use a capability on or through
197  * @cap: The capability to use
198  *
199  * Test to see if the opener of the socket had when the socket was created
200  * and the current process has the capability @cap over the network namespace
201  * the socket is a member of.
202  */
203 bool sk_net_capable(const struct sock *sk, int cap)
204 {
205 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
206 }
207 EXPORT_SYMBOL(sk_net_capable);
208 
209 /*
210  * Each address family might have different locking rules, so we have
211  * one slock key per address family and separate keys for internal and
212  * userspace sockets.
213  */
214 static struct lock_class_key af_family_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_keys[AF_MAX];
216 static struct lock_class_key af_family_slock_keys[AF_MAX];
217 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
218 
219 /*
220  * Make lock validator output more readable. (we pre-construct these
221  * strings build-time, so that runtime initialization of socket
222  * locks is fast):
223  */
224 
225 #define _sock_locks(x)						  \
226   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
227   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
228   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
229   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
230   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
231   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
232   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
233   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
234   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
235   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
236   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
237   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
238   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
239   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
240   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
241   x "AF_MCTP"  , \
242   x "AF_MAX"
243 
244 static const char *const af_family_key_strings[AF_MAX+1] = {
245 	_sock_locks("sk_lock-")
246 };
247 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
248 	_sock_locks("slock-")
249 };
250 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
251 	_sock_locks("clock-")
252 };
253 
254 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
255 	_sock_locks("k-sk_lock-")
256 };
257 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
258 	_sock_locks("k-slock-")
259 };
260 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
261 	_sock_locks("k-clock-")
262 };
263 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
264 	_sock_locks("rlock-")
265 };
266 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
267 	_sock_locks("wlock-")
268 };
269 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
270 	_sock_locks("elock-")
271 };
272 
273 /*
274  * sk_callback_lock and sk queues locking rules are per-address-family,
275  * so split the lock classes by using a per-AF key:
276  */
277 static struct lock_class_key af_callback_keys[AF_MAX];
278 static struct lock_class_key af_rlock_keys[AF_MAX];
279 static struct lock_class_key af_wlock_keys[AF_MAX];
280 static struct lock_class_key af_elock_keys[AF_MAX];
281 static struct lock_class_key af_kern_callback_keys[AF_MAX];
282 
283 /* Run time adjustable parameters. */
284 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
290 
291 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
292 EXPORT_SYMBOL_GPL(memalloc_socks_key);
293 
294 /**
295  * sk_set_memalloc - sets %SOCK_MEMALLOC
296  * @sk: socket to set it on
297  *
298  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
299  * It's the responsibility of the admin to adjust min_free_kbytes
300  * to meet the requirements
301  */
302 void sk_set_memalloc(struct sock *sk)
303 {
304 	sock_set_flag(sk, SOCK_MEMALLOC);
305 	sk->sk_allocation |= __GFP_MEMALLOC;
306 	static_branch_inc(&memalloc_socks_key);
307 }
308 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309 
310 void sk_clear_memalloc(struct sock *sk)
311 {
312 	sock_reset_flag(sk, SOCK_MEMALLOC);
313 	sk->sk_allocation &= ~__GFP_MEMALLOC;
314 	static_branch_dec(&memalloc_socks_key);
315 
316 	/*
317 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
318 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
319 	 * it has rmem allocations due to the last swapfile being deactivated
320 	 * but there is a risk that the socket is unusable due to exceeding
321 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 	 */
323 	sk_mem_reclaim(sk);
324 }
325 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326 
327 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
328 {
329 	int ret;
330 	unsigned int noreclaim_flag;
331 
332 	/* these should have been dropped before queueing */
333 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334 
335 	noreclaim_flag = memalloc_noreclaim_save();
336 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 				 tcp_v6_do_rcv,
338 				 tcp_v4_do_rcv,
339 				 sk, skb);
340 	memalloc_noreclaim_restore(noreclaim_flag);
341 
342 	return ret;
343 }
344 EXPORT_SYMBOL(__sk_backlog_rcv);
345 
346 void sk_error_report(struct sock *sk)
347 {
348 	sk->sk_error_report(sk);
349 
350 	switch (sk->sk_family) {
351 	case AF_INET:
352 		fallthrough;
353 	case AF_INET6:
354 		trace_inet_sk_error_report(sk);
355 		break;
356 	default:
357 		break;
358 	}
359 }
360 EXPORT_SYMBOL(sk_error_report);
361 
362 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 {
364 	struct __kernel_sock_timeval tv;
365 
366 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 		tv.tv_sec = 0;
368 		tv.tv_usec = 0;
369 	} else {
370 		tv.tv_sec = timeo / HZ;
371 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
372 	}
373 
374 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
375 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
376 		*(struct old_timeval32 *)optval = tv32;
377 		return sizeof(tv32);
378 	}
379 
380 	if (old_timeval) {
381 		struct __kernel_old_timeval old_tv;
382 		old_tv.tv_sec = tv.tv_sec;
383 		old_tv.tv_usec = tv.tv_usec;
384 		*(struct __kernel_old_timeval *)optval = old_tv;
385 		return sizeof(old_tv);
386 	}
387 
388 	*(struct __kernel_sock_timeval *)optval = tv;
389 	return sizeof(tv);
390 }
391 EXPORT_SYMBOL(sock_get_timeout);
392 
393 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
394 			   sockptr_t optval, int optlen, bool old_timeval)
395 {
396 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
397 		struct old_timeval32 tv32;
398 
399 		if (optlen < sizeof(tv32))
400 			return -EINVAL;
401 
402 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 			return -EFAULT;
404 		tv->tv_sec = tv32.tv_sec;
405 		tv->tv_usec = tv32.tv_usec;
406 	} else if (old_timeval) {
407 		struct __kernel_old_timeval old_tv;
408 
409 		if (optlen < sizeof(old_tv))
410 			return -EINVAL;
411 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 			return -EFAULT;
413 		tv->tv_sec = old_tv.tv_sec;
414 		tv->tv_usec = old_tv.tv_usec;
415 	} else {
416 		if (optlen < sizeof(*tv))
417 			return -EINVAL;
418 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
419 			return -EFAULT;
420 	}
421 
422 	return 0;
423 }
424 EXPORT_SYMBOL(sock_copy_user_timeval);
425 
426 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
427 			    bool old_timeval)
428 {
429 	struct __kernel_sock_timeval tv;
430 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
431 	long val;
432 
433 	if (err)
434 		return err;
435 
436 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
437 		return -EDOM;
438 
439 	if (tv.tv_sec < 0) {
440 		static int warned __read_mostly;
441 
442 		WRITE_ONCE(*timeo_p, 0);
443 		if (warned < 10 && net_ratelimit()) {
444 			warned++;
445 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
446 				__func__, current->comm, task_pid_nr(current));
447 		}
448 		return 0;
449 	}
450 	val = MAX_SCHEDULE_TIMEOUT;
451 	if ((tv.tv_sec || tv.tv_usec) &&
452 	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
453 		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 						    USEC_PER_SEC / HZ);
455 	WRITE_ONCE(*timeo_p, val);
456 	return 0;
457 }
458 
459 static bool sk_set_prio_allowed(const struct sock *sk, int val)
460 {
461 	return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
462 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
463 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
464 }
465 
466 static bool sock_needs_netstamp(const struct sock *sk)
467 {
468 	switch (sk->sk_family) {
469 	case AF_UNSPEC:
470 	case AF_UNIX:
471 		return false;
472 	default:
473 		return true;
474 	}
475 }
476 
477 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
478 {
479 	if (sk->sk_flags & flags) {
480 		sk->sk_flags &= ~flags;
481 		if (sock_needs_netstamp(sk) &&
482 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
483 			net_disable_timestamp();
484 	}
485 }
486 
487 
488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
489 {
490 	unsigned long flags;
491 	struct sk_buff_head *list = &sk->sk_receive_queue;
492 
493 	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
494 		atomic_inc(&sk->sk_drops);
495 		trace_sock_rcvqueue_full(sk, skb);
496 		return -ENOMEM;
497 	}
498 
499 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 		atomic_inc(&sk->sk_drops);
501 		return -ENOBUFS;
502 	}
503 
504 	skb->dev = NULL;
505 	skb_set_owner_r(skb, sk);
506 
507 	/* we escape from rcu protected region, make sure we dont leak
508 	 * a norefcounted dst
509 	 */
510 	skb_dst_force(skb);
511 
512 	spin_lock_irqsave(&list->lock, flags);
513 	sock_skb_set_dropcount(sk, skb);
514 	__skb_queue_tail(list, skb);
515 	spin_unlock_irqrestore(&list->lock, flags);
516 
517 	if (!sock_flag(sk, SOCK_DEAD))
518 		sk->sk_data_ready(sk);
519 	return 0;
520 }
521 EXPORT_SYMBOL(__sock_queue_rcv_skb);
522 
523 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
524 			      enum skb_drop_reason *reason)
525 {
526 	enum skb_drop_reason drop_reason;
527 	int err;
528 
529 	err = sk_filter(sk, skb);
530 	if (err) {
531 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
532 		goto out;
533 	}
534 	err = __sock_queue_rcv_skb(sk, skb);
535 	switch (err) {
536 	case -ENOMEM:
537 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
538 		break;
539 	case -ENOBUFS:
540 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
541 		break;
542 	default:
543 		drop_reason = SKB_NOT_DROPPED_YET;
544 		break;
545 	}
546 out:
547 	if (reason)
548 		*reason = drop_reason;
549 	return err;
550 }
551 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
552 
553 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
554 		     const int nested, unsigned int trim_cap, bool refcounted)
555 {
556 	int rc = NET_RX_SUCCESS;
557 
558 	if (sk_filter_trim_cap(sk, skb, trim_cap))
559 		goto discard_and_relse;
560 
561 	skb->dev = NULL;
562 
563 	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
564 		atomic_inc(&sk->sk_drops);
565 		goto discard_and_relse;
566 	}
567 	if (nested)
568 		bh_lock_sock_nested(sk);
569 	else
570 		bh_lock_sock(sk);
571 	if (!sock_owned_by_user(sk)) {
572 		/*
573 		 * trylock + unlock semantics:
574 		 */
575 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
576 
577 		rc = sk_backlog_rcv(sk, skb);
578 
579 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
580 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
581 		bh_unlock_sock(sk);
582 		atomic_inc(&sk->sk_drops);
583 		goto discard_and_relse;
584 	}
585 
586 	bh_unlock_sock(sk);
587 out:
588 	if (refcounted)
589 		sock_put(sk);
590 	return rc;
591 discard_and_relse:
592 	kfree_skb(skb);
593 	goto out;
594 }
595 EXPORT_SYMBOL(__sk_receive_skb);
596 
597 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
598 							  u32));
599 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
600 							   u32));
601 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
602 {
603 	struct dst_entry *dst = __sk_dst_get(sk);
604 
605 	if (dst && dst->obsolete &&
606 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
607 			       dst, cookie) == NULL) {
608 		sk_tx_queue_clear(sk);
609 		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
610 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
611 		dst_release(dst);
612 		return NULL;
613 	}
614 
615 	return dst;
616 }
617 EXPORT_SYMBOL(__sk_dst_check);
618 
619 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
620 {
621 	struct dst_entry *dst = sk_dst_get(sk);
622 
623 	if (dst && dst->obsolete &&
624 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
625 			       dst, cookie) == NULL) {
626 		sk_dst_reset(sk);
627 		dst_release(dst);
628 		return NULL;
629 	}
630 
631 	return dst;
632 }
633 EXPORT_SYMBOL(sk_dst_check);
634 
635 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
636 {
637 	int ret = -ENOPROTOOPT;
638 #ifdef CONFIG_NETDEVICES
639 	struct net *net = sock_net(sk);
640 
641 	/* Sorry... */
642 	ret = -EPERM;
643 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
644 		goto out;
645 
646 	ret = -EINVAL;
647 	if (ifindex < 0)
648 		goto out;
649 
650 	/* Paired with all READ_ONCE() done locklessly. */
651 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
652 
653 	if (sk->sk_prot->rehash)
654 		sk->sk_prot->rehash(sk);
655 	sk_dst_reset(sk);
656 
657 	ret = 0;
658 
659 out:
660 #endif
661 
662 	return ret;
663 }
664 
665 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
666 {
667 	int ret;
668 
669 	if (lock_sk)
670 		lock_sock(sk);
671 	ret = sock_bindtoindex_locked(sk, ifindex);
672 	if (lock_sk)
673 		release_sock(sk);
674 
675 	return ret;
676 }
677 EXPORT_SYMBOL(sock_bindtoindex);
678 
679 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
680 {
681 	int ret = -ENOPROTOOPT;
682 #ifdef CONFIG_NETDEVICES
683 	struct net *net = sock_net(sk);
684 	char devname[IFNAMSIZ];
685 	int index;
686 
687 	ret = -EINVAL;
688 	if (optlen < 0)
689 		goto out;
690 
691 	/* Bind this socket to a particular device like "eth0",
692 	 * as specified in the passed interface name. If the
693 	 * name is "" or the option length is zero the socket
694 	 * is not bound.
695 	 */
696 	if (optlen > IFNAMSIZ - 1)
697 		optlen = IFNAMSIZ - 1;
698 	memset(devname, 0, sizeof(devname));
699 
700 	ret = -EFAULT;
701 	if (copy_from_sockptr(devname, optval, optlen))
702 		goto out;
703 
704 	index = 0;
705 	if (devname[0] != '\0') {
706 		struct net_device *dev;
707 
708 		rcu_read_lock();
709 		dev = dev_get_by_name_rcu(net, devname);
710 		if (dev)
711 			index = dev->ifindex;
712 		rcu_read_unlock();
713 		ret = -ENODEV;
714 		if (!dev)
715 			goto out;
716 	}
717 
718 	sockopt_lock_sock(sk);
719 	ret = sock_bindtoindex_locked(sk, index);
720 	sockopt_release_sock(sk);
721 out:
722 #endif
723 
724 	return ret;
725 }
726 
727 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
728 				sockptr_t optlen, int len)
729 {
730 	int ret = -ENOPROTOOPT;
731 #ifdef CONFIG_NETDEVICES
732 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
733 	struct net *net = sock_net(sk);
734 	char devname[IFNAMSIZ];
735 
736 	if (bound_dev_if == 0) {
737 		len = 0;
738 		goto zero;
739 	}
740 
741 	ret = -EINVAL;
742 	if (len < IFNAMSIZ)
743 		goto out;
744 
745 	ret = netdev_get_name(net, devname, bound_dev_if);
746 	if (ret)
747 		goto out;
748 
749 	len = strlen(devname) + 1;
750 
751 	ret = -EFAULT;
752 	if (copy_to_sockptr(optval, devname, len))
753 		goto out;
754 
755 zero:
756 	ret = -EFAULT;
757 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
758 		goto out;
759 
760 	ret = 0;
761 
762 out:
763 #endif
764 
765 	return ret;
766 }
767 
768 bool sk_mc_loop(const struct sock *sk)
769 {
770 	if (dev_recursion_level())
771 		return false;
772 	if (!sk)
773 		return true;
774 	/* IPV6_ADDRFORM can change sk->sk_family under us. */
775 	switch (READ_ONCE(sk->sk_family)) {
776 	case AF_INET:
777 		return inet_test_bit(MC_LOOP, sk);
778 #if IS_ENABLED(CONFIG_IPV6)
779 	case AF_INET6:
780 		return inet6_test_bit(MC6_LOOP, sk);
781 #endif
782 	}
783 	WARN_ON_ONCE(1);
784 	return true;
785 }
786 EXPORT_SYMBOL(sk_mc_loop);
787 
788 void sock_set_reuseaddr(struct sock *sk)
789 {
790 	lock_sock(sk);
791 	sk->sk_reuse = SK_CAN_REUSE;
792 	release_sock(sk);
793 }
794 EXPORT_SYMBOL(sock_set_reuseaddr);
795 
796 void sock_set_reuseport(struct sock *sk)
797 {
798 	lock_sock(sk);
799 	sk->sk_reuseport = true;
800 	release_sock(sk);
801 }
802 EXPORT_SYMBOL(sock_set_reuseport);
803 
804 void sock_no_linger(struct sock *sk)
805 {
806 	lock_sock(sk);
807 	WRITE_ONCE(sk->sk_lingertime, 0);
808 	sock_set_flag(sk, SOCK_LINGER);
809 	release_sock(sk);
810 }
811 EXPORT_SYMBOL(sock_no_linger);
812 
813 void sock_set_priority(struct sock *sk, u32 priority)
814 {
815 	WRITE_ONCE(sk->sk_priority, priority);
816 }
817 EXPORT_SYMBOL(sock_set_priority);
818 
819 void sock_set_sndtimeo(struct sock *sk, s64 secs)
820 {
821 	lock_sock(sk);
822 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
823 		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
824 	else
825 		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
826 	release_sock(sk);
827 }
828 EXPORT_SYMBOL(sock_set_sndtimeo);
829 
830 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
831 {
832 	sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
833 	sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
834 	if (val)  {
835 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
836 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
837 	}
838 }
839 
840 void sock_enable_timestamps(struct sock *sk)
841 {
842 	lock_sock(sk);
843 	__sock_set_timestamps(sk, true, false, true);
844 	release_sock(sk);
845 }
846 EXPORT_SYMBOL(sock_enable_timestamps);
847 
848 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
849 {
850 	switch (optname) {
851 	case SO_TIMESTAMP_OLD:
852 		__sock_set_timestamps(sk, valbool, false, false);
853 		break;
854 	case SO_TIMESTAMP_NEW:
855 		__sock_set_timestamps(sk, valbool, true, false);
856 		break;
857 	case SO_TIMESTAMPNS_OLD:
858 		__sock_set_timestamps(sk, valbool, false, true);
859 		break;
860 	case SO_TIMESTAMPNS_NEW:
861 		__sock_set_timestamps(sk, valbool, true, true);
862 		break;
863 	}
864 }
865 
866 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
867 {
868 	struct net *net = sock_net(sk);
869 	struct net_device *dev = NULL;
870 	bool match = false;
871 	int *vclock_index;
872 	int i, num;
873 
874 	if (sk->sk_bound_dev_if)
875 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
876 
877 	if (!dev) {
878 		pr_err("%s: sock not bind to device\n", __func__);
879 		return -EOPNOTSUPP;
880 	}
881 
882 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
883 	dev_put(dev);
884 
885 	for (i = 0; i < num; i++) {
886 		if (*(vclock_index + i) == phc_index) {
887 			match = true;
888 			break;
889 		}
890 	}
891 
892 	if (num > 0)
893 		kfree(vclock_index);
894 
895 	if (!match)
896 		return -EINVAL;
897 
898 	WRITE_ONCE(sk->sk_bind_phc, phc_index);
899 
900 	return 0;
901 }
902 
903 int sock_set_timestamping(struct sock *sk, int optname,
904 			  struct so_timestamping timestamping)
905 {
906 	int val = timestamping.flags;
907 	int ret;
908 
909 	if (val & ~SOF_TIMESTAMPING_MASK)
910 		return -EINVAL;
911 
912 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
913 	    !(val & SOF_TIMESTAMPING_OPT_ID))
914 		return -EINVAL;
915 
916 	if (val & SOF_TIMESTAMPING_OPT_ID &&
917 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
918 		if (sk_is_tcp(sk)) {
919 			if ((1 << sk->sk_state) &
920 			    (TCPF_CLOSE | TCPF_LISTEN))
921 				return -EINVAL;
922 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
923 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
924 			else
925 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
926 		} else {
927 			atomic_set(&sk->sk_tskey, 0);
928 		}
929 	}
930 
931 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
932 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
933 		return -EINVAL;
934 
935 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
936 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
937 		if (ret)
938 			return ret;
939 	}
940 
941 	WRITE_ONCE(sk->sk_tsflags, val);
942 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
943 	sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
944 
945 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
946 		sock_enable_timestamp(sk,
947 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
948 	else
949 		sock_disable_timestamp(sk,
950 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
951 	return 0;
952 }
953 
954 #if defined(CONFIG_CGROUP_BPF)
955 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
956 {
957 	struct bpf_sock_ops_kern sock_ops;
958 
959 	memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
960 	sock_ops.op = op;
961 	sock_ops.is_fullsock = 1;
962 	sock_ops.sk = sk;
963 	bpf_skops_init_skb(&sock_ops, skb, 0);
964 	__cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
965 }
966 #endif
967 
968 void sock_set_keepalive(struct sock *sk)
969 {
970 	lock_sock(sk);
971 	if (sk->sk_prot->keepalive)
972 		sk->sk_prot->keepalive(sk, true);
973 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
974 	release_sock(sk);
975 }
976 EXPORT_SYMBOL(sock_set_keepalive);
977 
978 static void __sock_set_rcvbuf(struct sock *sk, int val)
979 {
980 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
981 	 * as a negative value.
982 	 */
983 	val = min_t(int, val, INT_MAX / 2);
984 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
985 
986 	/* We double it on the way in to account for "struct sk_buff" etc.
987 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
988 	 * will allow that much actual data to be received on that socket.
989 	 *
990 	 * Applications are unaware that "struct sk_buff" and other overheads
991 	 * allocate from the receive buffer during socket buffer allocation.
992 	 *
993 	 * And after considering the possible alternatives, returning the value
994 	 * we actually used in getsockopt is the most desirable behavior.
995 	 */
996 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
997 }
998 
999 void sock_set_rcvbuf(struct sock *sk, int val)
1000 {
1001 	lock_sock(sk);
1002 	__sock_set_rcvbuf(sk, val);
1003 	release_sock(sk);
1004 }
1005 EXPORT_SYMBOL(sock_set_rcvbuf);
1006 
1007 static void __sock_set_mark(struct sock *sk, u32 val)
1008 {
1009 	if (val != sk->sk_mark) {
1010 		WRITE_ONCE(sk->sk_mark, val);
1011 		sk_dst_reset(sk);
1012 	}
1013 }
1014 
1015 void sock_set_mark(struct sock *sk, u32 val)
1016 {
1017 	lock_sock(sk);
1018 	__sock_set_mark(sk, val);
1019 	release_sock(sk);
1020 }
1021 EXPORT_SYMBOL(sock_set_mark);
1022 
1023 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1024 {
1025 	/* Round down bytes to multiple of pages */
1026 	bytes = round_down(bytes, PAGE_SIZE);
1027 
1028 	WARN_ON(bytes > sk->sk_reserved_mem);
1029 	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1030 	sk_mem_reclaim(sk);
1031 }
1032 
1033 static int sock_reserve_memory(struct sock *sk, int bytes)
1034 {
1035 	long allocated;
1036 	bool charged;
1037 	int pages;
1038 
1039 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1040 		return -EOPNOTSUPP;
1041 
1042 	if (!bytes)
1043 		return 0;
1044 
1045 	pages = sk_mem_pages(bytes);
1046 
1047 	/* pre-charge to memcg */
1048 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1049 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1050 	if (!charged)
1051 		return -ENOMEM;
1052 
1053 	/* pre-charge to forward_alloc */
1054 	sk_memory_allocated_add(sk, pages);
1055 	allocated = sk_memory_allocated(sk);
1056 	/* If the system goes into memory pressure with this
1057 	 * precharge, give up and return error.
1058 	 */
1059 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1060 		sk_memory_allocated_sub(sk, pages);
1061 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1062 		return -ENOMEM;
1063 	}
1064 	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1065 
1066 	WRITE_ONCE(sk->sk_reserved_mem,
1067 		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1068 
1069 	return 0;
1070 }
1071 
1072 #ifdef CONFIG_PAGE_POOL
1073 
1074 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1075  * in 1 syscall. The limit exists to limit the amount of memory the kernel
1076  * allocates to copy these tokens, and to prevent looping over the frags for
1077  * too long.
1078  */
1079 #define MAX_DONTNEED_TOKENS 128
1080 #define MAX_DONTNEED_FRAGS 1024
1081 
1082 static noinline_for_stack int
1083 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1084 {
1085 	unsigned int num_tokens, i, j, k, netmem_num = 0;
1086 	struct dmabuf_token *tokens;
1087 	int ret = 0, num_frags = 0;
1088 	netmem_ref netmems[16];
1089 
1090 	if (!sk_is_tcp(sk))
1091 		return -EBADF;
1092 
1093 	if (optlen % sizeof(*tokens) ||
1094 	    optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1095 		return -EINVAL;
1096 
1097 	num_tokens = optlen / sizeof(*tokens);
1098 	tokens = kvmalloc_array(num_tokens, sizeof(*tokens), GFP_KERNEL);
1099 	if (!tokens)
1100 		return -ENOMEM;
1101 
1102 	if (copy_from_sockptr(tokens, optval, optlen)) {
1103 		kvfree(tokens);
1104 		return -EFAULT;
1105 	}
1106 
1107 	xa_lock_bh(&sk->sk_user_frags);
1108 	for (i = 0; i < num_tokens; i++) {
1109 		for (j = 0; j < tokens[i].token_count; j++) {
1110 			if (++num_frags > MAX_DONTNEED_FRAGS)
1111 				goto frag_limit_reached;
1112 
1113 			netmem_ref netmem = (__force netmem_ref)__xa_erase(
1114 				&sk->sk_user_frags, tokens[i].token_start + j);
1115 
1116 			if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1117 				continue;
1118 
1119 			netmems[netmem_num++] = netmem;
1120 			if (netmem_num == ARRAY_SIZE(netmems)) {
1121 				xa_unlock_bh(&sk->sk_user_frags);
1122 				for (k = 0; k < netmem_num; k++)
1123 					WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1124 				netmem_num = 0;
1125 				xa_lock_bh(&sk->sk_user_frags);
1126 			}
1127 			ret++;
1128 		}
1129 	}
1130 
1131 frag_limit_reached:
1132 	xa_unlock_bh(&sk->sk_user_frags);
1133 	for (k = 0; k < netmem_num; k++)
1134 		WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1135 
1136 	kvfree(tokens);
1137 	return ret;
1138 }
1139 #endif
1140 
1141 void sockopt_lock_sock(struct sock *sk)
1142 {
1143 	/* When current->bpf_ctx is set, the setsockopt is called from
1144 	 * a bpf prog.  bpf has ensured the sk lock has been
1145 	 * acquired before calling setsockopt().
1146 	 */
1147 	if (has_current_bpf_ctx())
1148 		return;
1149 
1150 	lock_sock(sk);
1151 }
1152 EXPORT_SYMBOL(sockopt_lock_sock);
1153 
1154 void sockopt_release_sock(struct sock *sk)
1155 {
1156 	if (has_current_bpf_ctx())
1157 		return;
1158 
1159 	release_sock(sk);
1160 }
1161 EXPORT_SYMBOL(sockopt_release_sock);
1162 
1163 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1164 {
1165 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1166 }
1167 EXPORT_SYMBOL(sockopt_ns_capable);
1168 
1169 bool sockopt_capable(int cap)
1170 {
1171 	return has_current_bpf_ctx() || capable(cap);
1172 }
1173 EXPORT_SYMBOL(sockopt_capable);
1174 
1175 static int sockopt_validate_clockid(__kernel_clockid_t value)
1176 {
1177 	switch (value) {
1178 	case CLOCK_REALTIME:
1179 	case CLOCK_MONOTONIC:
1180 	case CLOCK_TAI:
1181 		return 0;
1182 	}
1183 	return -EINVAL;
1184 }
1185 
1186 /*
1187  *	This is meant for all protocols to use and covers goings on
1188  *	at the socket level. Everything here is generic.
1189  */
1190 
1191 int sk_setsockopt(struct sock *sk, int level, int optname,
1192 		  sockptr_t optval, unsigned int optlen)
1193 {
1194 	struct so_timestamping timestamping;
1195 	struct socket *sock = sk->sk_socket;
1196 	struct sock_txtime sk_txtime;
1197 	int val;
1198 	int valbool;
1199 	struct linger ling;
1200 	int ret = 0;
1201 
1202 	/*
1203 	 *	Options without arguments
1204 	 */
1205 
1206 	if (optname == SO_BINDTODEVICE)
1207 		return sock_setbindtodevice(sk, optval, optlen);
1208 
1209 	if (optlen < sizeof(int))
1210 		return -EINVAL;
1211 
1212 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1213 		return -EFAULT;
1214 
1215 	valbool = val ? 1 : 0;
1216 
1217 	/* handle options which do not require locking the socket. */
1218 	switch (optname) {
1219 	case SO_PRIORITY:
1220 		if (sk_set_prio_allowed(sk, val)) {
1221 			sock_set_priority(sk, val);
1222 			return 0;
1223 		}
1224 		return -EPERM;
1225 	case SO_PASSSEC:
1226 		assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1227 		return 0;
1228 	case SO_PASSCRED:
1229 		assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1230 		return 0;
1231 	case SO_PASSPIDFD:
1232 		assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1233 		return 0;
1234 	case SO_TYPE:
1235 	case SO_PROTOCOL:
1236 	case SO_DOMAIN:
1237 	case SO_ERROR:
1238 		return -ENOPROTOOPT;
1239 #ifdef CONFIG_NET_RX_BUSY_POLL
1240 	case SO_BUSY_POLL:
1241 		if (val < 0)
1242 			return -EINVAL;
1243 		WRITE_ONCE(sk->sk_ll_usec, val);
1244 		return 0;
1245 	case SO_PREFER_BUSY_POLL:
1246 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1247 			return -EPERM;
1248 		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1249 		return 0;
1250 	case SO_BUSY_POLL_BUDGET:
1251 		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1252 		    !sockopt_capable(CAP_NET_ADMIN))
1253 			return -EPERM;
1254 		if (val < 0 || val > U16_MAX)
1255 			return -EINVAL;
1256 		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1257 		return 0;
1258 #endif
1259 	case SO_MAX_PACING_RATE:
1260 		{
1261 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1262 		unsigned long pacing_rate;
1263 
1264 		if (sizeof(ulval) != sizeof(val) &&
1265 		    optlen >= sizeof(ulval) &&
1266 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1267 			return -EFAULT;
1268 		}
1269 		if (ulval != ~0UL)
1270 			cmpxchg(&sk->sk_pacing_status,
1271 				SK_PACING_NONE,
1272 				SK_PACING_NEEDED);
1273 		/* Pairs with READ_ONCE() from sk_getsockopt() */
1274 		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1275 		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1276 		if (ulval < pacing_rate)
1277 			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1278 		return 0;
1279 		}
1280 	case SO_TXREHASH:
1281 		if (val < -1 || val > 1)
1282 			return -EINVAL;
1283 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1284 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1285 		/* Paired with READ_ONCE() in tcp_rtx_synack()
1286 		 * and sk_getsockopt().
1287 		 */
1288 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1289 		return 0;
1290 	case SO_PEEK_OFF:
1291 		{
1292 		int (*set_peek_off)(struct sock *sk, int val);
1293 
1294 		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1295 		if (set_peek_off)
1296 			ret = set_peek_off(sk, val);
1297 		else
1298 			ret = -EOPNOTSUPP;
1299 		return ret;
1300 		}
1301 #ifdef CONFIG_PAGE_POOL
1302 	case SO_DEVMEM_DONTNEED:
1303 		return sock_devmem_dontneed(sk, optval, optlen);
1304 #endif
1305 	}
1306 
1307 	sockopt_lock_sock(sk);
1308 
1309 	switch (optname) {
1310 	case SO_DEBUG:
1311 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1312 			ret = -EACCES;
1313 		else
1314 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1315 		break;
1316 	case SO_REUSEADDR:
1317 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1318 		break;
1319 	case SO_REUSEPORT:
1320 		if (valbool && !sk_is_inet(sk))
1321 			ret = -EOPNOTSUPP;
1322 		else
1323 			sk->sk_reuseport = valbool;
1324 		break;
1325 	case SO_DONTROUTE:
1326 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1327 		sk_dst_reset(sk);
1328 		break;
1329 	case SO_BROADCAST:
1330 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1331 		break;
1332 	case SO_SNDBUF:
1333 		/* Don't error on this BSD doesn't and if you think
1334 		 * about it this is right. Otherwise apps have to
1335 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1336 		 * are treated in BSD as hints
1337 		 */
1338 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1339 set_sndbuf:
1340 		/* Ensure val * 2 fits into an int, to prevent max_t()
1341 		 * from treating it as a negative value.
1342 		 */
1343 		val = min_t(int, val, INT_MAX / 2);
1344 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1345 		WRITE_ONCE(sk->sk_sndbuf,
1346 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1347 		/* Wake up sending tasks if we upped the value. */
1348 		sk->sk_write_space(sk);
1349 		break;
1350 
1351 	case SO_SNDBUFFORCE:
1352 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1353 			ret = -EPERM;
1354 			break;
1355 		}
1356 
1357 		/* No negative values (to prevent underflow, as val will be
1358 		 * multiplied by 2).
1359 		 */
1360 		if (val < 0)
1361 			val = 0;
1362 		goto set_sndbuf;
1363 
1364 	case SO_RCVBUF:
1365 		/* Don't error on this BSD doesn't and if you think
1366 		 * about it this is right. Otherwise apps have to
1367 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1368 		 * are treated in BSD as hints
1369 		 */
1370 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1371 		break;
1372 
1373 	case SO_RCVBUFFORCE:
1374 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1375 			ret = -EPERM;
1376 			break;
1377 		}
1378 
1379 		/* No negative values (to prevent underflow, as val will be
1380 		 * multiplied by 2).
1381 		 */
1382 		__sock_set_rcvbuf(sk, max(val, 0));
1383 		break;
1384 
1385 	case SO_KEEPALIVE:
1386 		if (sk->sk_prot->keepalive)
1387 			sk->sk_prot->keepalive(sk, valbool);
1388 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1389 		break;
1390 
1391 	case SO_OOBINLINE:
1392 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1393 		break;
1394 
1395 	case SO_NO_CHECK:
1396 		sk->sk_no_check_tx = valbool;
1397 		break;
1398 
1399 	case SO_LINGER:
1400 		if (optlen < sizeof(ling)) {
1401 			ret = -EINVAL;	/* 1003.1g */
1402 			break;
1403 		}
1404 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1405 			ret = -EFAULT;
1406 			break;
1407 		}
1408 		if (!ling.l_onoff) {
1409 			sock_reset_flag(sk, SOCK_LINGER);
1410 		} else {
1411 			unsigned long t_sec = ling.l_linger;
1412 
1413 			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1414 				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1415 			else
1416 				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1417 			sock_set_flag(sk, SOCK_LINGER);
1418 		}
1419 		break;
1420 
1421 	case SO_BSDCOMPAT:
1422 		break;
1423 
1424 	case SO_TIMESTAMP_OLD:
1425 	case SO_TIMESTAMP_NEW:
1426 	case SO_TIMESTAMPNS_OLD:
1427 	case SO_TIMESTAMPNS_NEW:
1428 		sock_set_timestamp(sk, optname, valbool);
1429 		break;
1430 
1431 	case SO_TIMESTAMPING_NEW:
1432 	case SO_TIMESTAMPING_OLD:
1433 		if (optlen == sizeof(timestamping)) {
1434 			if (copy_from_sockptr(&timestamping, optval,
1435 					      sizeof(timestamping))) {
1436 				ret = -EFAULT;
1437 				break;
1438 			}
1439 		} else {
1440 			memset(&timestamping, 0, sizeof(timestamping));
1441 			timestamping.flags = val;
1442 		}
1443 		ret = sock_set_timestamping(sk, optname, timestamping);
1444 		break;
1445 
1446 	case SO_RCVLOWAT:
1447 		{
1448 		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1449 
1450 		if (val < 0)
1451 			val = INT_MAX;
1452 		if (sock)
1453 			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1454 		if (set_rcvlowat)
1455 			ret = set_rcvlowat(sk, val);
1456 		else
1457 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1458 		break;
1459 		}
1460 	case SO_RCVTIMEO_OLD:
1461 	case SO_RCVTIMEO_NEW:
1462 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1463 				       optlen, optname == SO_RCVTIMEO_OLD);
1464 		break;
1465 
1466 	case SO_SNDTIMEO_OLD:
1467 	case SO_SNDTIMEO_NEW:
1468 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1469 				       optlen, optname == SO_SNDTIMEO_OLD);
1470 		break;
1471 
1472 	case SO_ATTACH_FILTER: {
1473 		struct sock_fprog fprog;
1474 
1475 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1476 		if (!ret)
1477 			ret = sk_attach_filter(&fprog, sk);
1478 		break;
1479 	}
1480 	case SO_ATTACH_BPF:
1481 		ret = -EINVAL;
1482 		if (optlen == sizeof(u32)) {
1483 			u32 ufd;
1484 
1485 			ret = -EFAULT;
1486 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1487 				break;
1488 
1489 			ret = sk_attach_bpf(ufd, sk);
1490 		}
1491 		break;
1492 
1493 	case SO_ATTACH_REUSEPORT_CBPF: {
1494 		struct sock_fprog fprog;
1495 
1496 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1497 		if (!ret)
1498 			ret = sk_reuseport_attach_filter(&fprog, sk);
1499 		break;
1500 	}
1501 	case SO_ATTACH_REUSEPORT_EBPF:
1502 		ret = -EINVAL;
1503 		if (optlen == sizeof(u32)) {
1504 			u32 ufd;
1505 
1506 			ret = -EFAULT;
1507 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1508 				break;
1509 
1510 			ret = sk_reuseport_attach_bpf(ufd, sk);
1511 		}
1512 		break;
1513 
1514 	case SO_DETACH_REUSEPORT_BPF:
1515 		ret = reuseport_detach_prog(sk);
1516 		break;
1517 
1518 	case SO_DETACH_FILTER:
1519 		ret = sk_detach_filter(sk);
1520 		break;
1521 
1522 	case SO_LOCK_FILTER:
1523 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1524 			ret = -EPERM;
1525 		else
1526 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1527 		break;
1528 
1529 	case SO_MARK:
1530 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1531 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1532 			ret = -EPERM;
1533 			break;
1534 		}
1535 
1536 		__sock_set_mark(sk, val);
1537 		break;
1538 	case SO_RCVMARK:
1539 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1540 		break;
1541 
1542 	case SO_RCVPRIORITY:
1543 		sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1544 		break;
1545 
1546 	case SO_RXQ_OVFL:
1547 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1548 		break;
1549 
1550 	case SO_WIFI_STATUS:
1551 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1552 		break;
1553 
1554 	case SO_NOFCS:
1555 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1556 		break;
1557 
1558 	case SO_SELECT_ERR_QUEUE:
1559 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1560 		break;
1561 
1562 
1563 	case SO_INCOMING_CPU:
1564 		reuseport_update_incoming_cpu(sk, val);
1565 		break;
1566 
1567 	case SO_CNX_ADVICE:
1568 		if (val == 1)
1569 			dst_negative_advice(sk);
1570 		break;
1571 
1572 	case SO_ZEROCOPY:
1573 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1574 			if (!(sk_is_tcp(sk) ||
1575 			      (sk->sk_type == SOCK_DGRAM &&
1576 			       sk->sk_protocol == IPPROTO_UDP)))
1577 				ret = -EOPNOTSUPP;
1578 		} else if (sk->sk_family != PF_RDS) {
1579 			ret = -EOPNOTSUPP;
1580 		}
1581 		if (!ret) {
1582 			if (val < 0 || val > 1)
1583 				ret = -EINVAL;
1584 			else
1585 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1586 		}
1587 		break;
1588 
1589 	case SO_TXTIME:
1590 		if (optlen != sizeof(struct sock_txtime)) {
1591 			ret = -EINVAL;
1592 			break;
1593 		} else if (copy_from_sockptr(&sk_txtime, optval,
1594 			   sizeof(struct sock_txtime))) {
1595 			ret = -EFAULT;
1596 			break;
1597 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1598 			ret = -EINVAL;
1599 			break;
1600 		}
1601 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1602 		 * scheduler has enough safe guards.
1603 		 */
1604 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1605 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1606 			ret = -EPERM;
1607 			break;
1608 		}
1609 
1610 		ret = sockopt_validate_clockid(sk_txtime.clockid);
1611 		if (ret)
1612 			break;
1613 
1614 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1615 		sk->sk_clockid = sk_txtime.clockid;
1616 		sk->sk_txtime_deadline_mode =
1617 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1618 		sk->sk_txtime_report_errors =
1619 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1620 		break;
1621 
1622 	case SO_BINDTOIFINDEX:
1623 		ret = sock_bindtoindex_locked(sk, val);
1624 		break;
1625 
1626 	case SO_BUF_LOCK:
1627 		if (val & ~SOCK_BUF_LOCK_MASK) {
1628 			ret = -EINVAL;
1629 			break;
1630 		}
1631 		sk->sk_userlocks = val | (sk->sk_userlocks &
1632 					  ~SOCK_BUF_LOCK_MASK);
1633 		break;
1634 
1635 	case SO_RESERVE_MEM:
1636 	{
1637 		int delta;
1638 
1639 		if (val < 0) {
1640 			ret = -EINVAL;
1641 			break;
1642 		}
1643 
1644 		delta = val - sk->sk_reserved_mem;
1645 		if (delta < 0)
1646 			sock_release_reserved_memory(sk, -delta);
1647 		else
1648 			ret = sock_reserve_memory(sk, delta);
1649 		break;
1650 	}
1651 
1652 	default:
1653 		ret = -ENOPROTOOPT;
1654 		break;
1655 	}
1656 	sockopt_release_sock(sk);
1657 	return ret;
1658 }
1659 
1660 int sock_setsockopt(struct socket *sock, int level, int optname,
1661 		    sockptr_t optval, unsigned int optlen)
1662 {
1663 	return sk_setsockopt(sock->sk, level, optname,
1664 			     optval, optlen);
1665 }
1666 EXPORT_SYMBOL(sock_setsockopt);
1667 
1668 static const struct cred *sk_get_peer_cred(struct sock *sk)
1669 {
1670 	const struct cred *cred;
1671 
1672 	spin_lock(&sk->sk_peer_lock);
1673 	cred = get_cred(sk->sk_peer_cred);
1674 	spin_unlock(&sk->sk_peer_lock);
1675 
1676 	return cred;
1677 }
1678 
1679 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1680 			  struct ucred *ucred)
1681 {
1682 	ucred->pid = pid_vnr(pid);
1683 	ucred->uid = ucred->gid = -1;
1684 	if (cred) {
1685 		struct user_namespace *current_ns = current_user_ns();
1686 
1687 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1688 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1689 	}
1690 }
1691 
1692 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1693 {
1694 	struct user_namespace *user_ns = current_user_ns();
1695 	int i;
1696 
1697 	for (i = 0; i < src->ngroups; i++) {
1698 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1699 
1700 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1701 			return -EFAULT;
1702 	}
1703 
1704 	return 0;
1705 }
1706 
1707 int sk_getsockopt(struct sock *sk, int level, int optname,
1708 		  sockptr_t optval, sockptr_t optlen)
1709 {
1710 	struct socket *sock = sk->sk_socket;
1711 
1712 	union {
1713 		int val;
1714 		u64 val64;
1715 		unsigned long ulval;
1716 		struct linger ling;
1717 		struct old_timeval32 tm32;
1718 		struct __kernel_old_timeval tm;
1719 		struct  __kernel_sock_timeval stm;
1720 		struct sock_txtime txtime;
1721 		struct so_timestamping timestamping;
1722 	} v;
1723 
1724 	int lv = sizeof(int);
1725 	int len;
1726 
1727 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1728 		return -EFAULT;
1729 	if (len < 0)
1730 		return -EINVAL;
1731 
1732 	memset(&v, 0, sizeof(v));
1733 
1734 	switch (optname) {
1735 	case SO_DEBUG:
1736 		v.val = sock_flag(sk, SOCK_DBG);
1737 		break;
1738 
1739 	case SO_DONTROUTE:
1740 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1741 		break;
1742 
1743 	case SO_BROADCAST:
1744 		v.val = sock_flag(sk, SOCK_BROADCAST);
1745 		break;
1746 
1747 	case SO_SNDBUF:
1748 		v.val = READ_ONCE(sk->sk_sndbuf);
1749 		break;
1750 
1751 	case SO_RCVBUF:
1752 		v.val = READ_ONCE(sk->sk_rcvbuf);
1753 		break;
1754 
1755 	case SO_REUSEADDR:
1756 		v.val = sk->sk_reuse;
1757 		break;
1758 
1759 	case SO_REUSEPORT:
1760 		v.val = sk->sk_reuseport;
1761 		break;
1762 
1763 	case SO_KEEPALIVE:
1764 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1765 		break;
1766 
1767 	case SO_TYPE:
1768 		v.val = sk->sk_type;
1769 		break;
1770 
1771 	case SO_PROTOCOL:
1772 		v.val = sk->sk_protocol;
1773 		break;
1774 
1775 	case SO_DOMAIN:
1776 		v.val = sk->sk_family;
1777 		break;
1778 
1779 	case SO_ERROR:
1780 		v.val = -sock_error(sk);
1781 		if (v.val == 0)
1782 			v.val = xchg(&sk->sk_err_soft, 0);
1783 		break;
1784 
1785 	case SO_OOBINLINE:
1786 		v.val = sock_flag(sk, SOCK_URGINLINE);
1787 		break;
1788 
1789 	case SO_NO_CHECK:
1790 		v.val = sk->sk_no_check_tx;
1791 		break;
1792 
1793 	case SO_PRIORITY:
1794 		v.val = READ_ONCE(sk->sk_priority);
1795 		break;
1796 
1797 	case SO_LINGER:
1798 		lv		= sizeof(v.ling);
1799 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1800 		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1801 		break;
1802 
1803 	case SO_BSDCOMPAT:
1804 		break;
1805 
1806 	case SO_TIMESTAMP_OLD:
1807 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1808 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1809 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1810 		break;
1811 
1812 	case SO_TIMESTAMPNS_OLD:
1813 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1814 		break;
1815 
1816 	case SO_TIMESTAMP_NEW:
1817 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1818 		break;
1819 
1820 	case SO_TIMESTAMPNS_NEW:
1821 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1822 		break;
1823 
1824 	case SO_TIMESTAMPING_OLD:
1825 	case SO_TIMESTAMPING_NEW:
1826 		lv = sizeof(v.timestamping);
1827 		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1828 		 * returning the flags when they were set through the same option.
1829 		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1830 		 */
1831 		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1832 			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1833 			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1834 		}
1835 		break;
1836 
1837 	case SO_RCVTIMEO_OLD:
1838 	case SO_RCVTIMEO_NEW:
1839 		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1840 				      SO_RCVTIMEO_OLD == optname);
1841 		break;
1842 
1843 	case SO_SNDTIMEO_OLD:
1844 	case SO_SNDTIMEO_NEW:
1845 		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1846 				      SO_SNDTIMEO_OLD == optname);
1847 		break;
1848 
1849 	case SO_RCVLOWAT:
1850 		v.val = READ_ONCE(sk->sk_rcvlowat);
1851 		break;
1852 
1853 	case SO_SNDLOWAT:
1854 		v.val = 1;
1855 		break;
1856 
1857 	case SO_PASSCRED:
1858 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1859 		break;
1860 
1861 	case SO_PASSPIDFD:
1862 		v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1863 		break;
1864 
1865 	case SO_PEERCRED:
1866 	{
1867 		struct ucred peercred;
1868 		if (len > sizeof(peercred))
1869 			len = sizeof(peercred);
1870 
1871 		spin_lock(&sk->sk_peer_lock);
1872 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1873 		spin_unlock(&sk->sk_peer_lock);
1874 
1875 		if (copy_to_sockptr(optval, &peercred, len))
1876 			return -EFAULT;
1877 		goto lenout;
1878 	}
1879 
1880 	case SO_PEERPIDFD:
1881 	{
1882 		struct pid *peer_pid;
1883 		struct file *pidfd_file = NULL;
1884 		unsigned int flags = 0;
1885 		int pidfd;
1886 
1887 		if (len > sizeof(pidfd))
1888 			len = sizeof(pidfd);
1889 
1890 		spin_lock(&sk->sk_peer_lock);
1891 		peer_pid = get_pid(sk->sk_peer_pid);
1892 		spin_unlock(&sk->sk_peer_lock);
1893 
1894 		if (!peer_pid)
1895 			return -ENODATA;
1896 
1897 		/* The use of PIDFD_STALE requires stashing of struct pid
1898 		 * on pidfs with pidfs_register_pid() and only AF_UNIX
1899 		 * were prepared for this.
1900 		 */
1901 		if (sk->sk_family == AF_UNIX)
1902 			flags = PIDFD_STALE;
1903 
1904 		pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1905 		put_pid(peer_pid);
1906 		if (pidfd < 0)
1907 			return pidfd;
1908 
1909 		if (copy_to_sockptr(optval, &pidfd, len) ||
1910 		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1911 			put_unused_fd(pidfd);
1912 			fput(pidfd_file);
1913 
1914 			return -EFAULT;
1915 		}
1916 
1917 		fd_install(pidfd, pidfd_file);
1918 		return 0;
1919 	}
1920 
1921 	case SO_PEERGROUPS:
1922 	{
1923 		const struct cred *cred;
1924 		int ret, n;
1925 
1926 		cred = sk_get_peer_cred(sk);
1927 		if (!cred)
1928 			return -ENODATA;
1929 
1930 		n = cred->group_info->ngroups;
1931 		if (len < n * sizeof(gid_t)) {
1932 			len = n * sizeof(gid_t);
1933 			put_cred(cred);
1934 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1935 		}
1936 		len = n * sizeof(gid_t);
1937 
1938 		ret = groups_to_user(optval, cred->group_info);
1939 		put_cred(cred);
1940 		if (ret)
1941 			return ret;
1942 		goto lenout;
1943 	}
1944 
1945 	case SO_PEERNAME:
1946 	{
1947 		struct sockaddr_storage address;
1948 
1949 		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1950 		if (lv < 0)
1951 			return -ENOTCONN;
1952 		if (lv < len)
1953 			return -EINVAL;
1954 		if (copy_to_sockptr(optval, &address, len))
1955 			return -EFAULT;
1956 		goto lenout;
1957 	}
1958 
1959 	/* Dubious BSD thing... Probably nobody even uses it, but
1960 	 * the UNIX standard wants it for whatever reason... -DaveM
1961 	 */
1962 	case SO_ACCEPTCONN:
1963 		v.val = sk->sk_state == TCP_LISTEN;
1964 		break;
1965 
1966 	case SO_PASSSEC:
1967 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1968 		break;
1969 
1970 	case SO_PEERSEC:
1971 		return security_socket_getpeersec_stream(sock,
1972 							 optval, optlen, len);
1973 
1974 	case SO_MARK:
1975 		v.val = READ_ONCE(sk->sk_mark);
1976 		break;
1977 
1978 	case SO_RCVMARK:
1979 		v.val = sock_flag(sk, SOCK_RCVMARK);
1980 		break;
1981 
1982 	case SO_RCVPRIORITY:
1983 		v.val = sock_flag(sk, SOCK_RCVPRIORITY);
1984 		break;
1985 
1986 	case SO_RXQ_OVFL:
1987 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1988 		break;
1989 
1990 	case SO_WIFI_STATUS:
1991 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1992 		break;
1993 
1994 	case SO_PEEK_OFF:
1995 		if (!READ_ONCE(sock->ops)->set_peek_off)
1996 			return -EOPNOTSUPP;
1997 
1998 		v.val = READ_ONCE(sk->sk_peek_off);
1999 		break;
2000 	case SO_NOFCS:
2001 		v.val = sock_flag(sk, SOCK_NOFCS);
2002 		break;
2003 
2004 	case SO_BINDTODEVICE:
2005 		return sock_getbindtodevice(sk, optval, optlen, len);
2006 
2007 	case SO_GET_FILTER:
2008 		len = sk_get_filter(sk, optval, len);
2009 		if (len < 0)
2010 			return len;
2011 
2012 		goto lenout;
2013 
2014 	case SO_LOCK_FILTER:
2015 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2016 		break;
2017 
2018 	case SO_BPF_EXTENSIONS:
2019 		v.val = bpf_tell_extensions();
2020 		break;
2021 
2022 	case SO_SELECT_ERR_QUEUE:
2023 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2024 		break;
2025 
2026 #ifdef CONFIG_NET_RX_BUSY_POLL
2027 	case SO_BUSY_POLL:
2028 		v.val = READ_ONCE(sk->sk_ll_usec);
2029 		break;
2030 	case SO_PREFER_BUSY_POLL:
2031 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2032 		break;
2033 #endif
2034 
2035 	case SO_MAX_PACING_RATE:
2036 		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2037 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2038 			lv = sizeof(v.ulval);
2039 			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2040 		} else {
2041 			/* 32bit version */
2042 			v.val = min_t(unsigned long, ~0U,
2043 				      READ_ONCE(sk->sk_max_pacing_rate));
2044 		}
2045 		break;
2046 
2047 	case SO_INCOMING_CPU:
2048 		v.val = READ_ONCE(sk->sk_incoming_cpu);
2049 		break;
2050 
2051 	case SO_MEMINFO:
2052 	{
2053 		u32 meminfo[SK_MEMINFO_VARS];
2054 
2055 		sk_get_meminfo(sk, meminfo);
2056 
2057 		len = min_t(unsigned int, len, sizeof(meminfo));
2058 		if (copy_to_sockptr(optval, &meminfo, len))
2059 			return -EFAULT;
2060 
2061 		goto lenout;
2062 	}
2063 
2064 #ifdef CONFIG_NET_RX_BUSY_POLL
2065 	case SO_INCOMING_NAPI_ID:
2066 		v.val = READ_ONCE(sk->sk_napi_id);
2067 
2068 		/* aggregate non-NAPI IDs down to 0 */
2069 		if (!napi_id_valid(v.val))
2070 			v.val = 0;
2071 
2072 		break;
2073 #endif
2074 
2075 	case SO_COOKIE:
2076 		lv = sizeof(u64);
2077 		if (len < lv)
2078 			return -EINVAL;
2079 		v.val64 = sock_gen_cookie(sk);
2080 		break;
2081 
2082 	case SO_ZEROCOPY:
2083 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
2084 		break;
2085 
2086 	case SO_TXTIME:
2087 		lv = sizeof(v.txtime);
2088 		v.txtime.clockid = sk->sk_clockid;
2089 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2090 				  SOF_TXTIME_DEADLINE_MODE : 0;
2091 		v.txtime.flags |= sk->sk_txtime_report_errors ?
2092 				  SOF_TXTIME_REPORT_ERRORS : 0;
2093 		break;
2094 
2095 	case SO_BINDTOIFINDEX:
2096 		v.val = READ_ONCE(sk->sk_bound_dev_if);
2097 		break;
2098 
2099 	case SO_NETNS_COOKIE:
2100 		lv = sizeof(u64);
2101 		if (len != lv)
2102 			return -EINVAL;
2103 		v.val64 = sock_net(sk)->net_cookie;
2104 		break;
2105 
2106 	case SO_BUF_LOCK:
2107 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2108 		break;
2109 
2110 	case SO_RESERVE_MEM:
2111 		v.val = READ_ONCE(sk->sk_reserved_mem);
2112 		break;
2113 
2114 	case SO_TXREHASH:
2115 		/* Paired with WRITE_ONCE() in sk_setsockopt() */
2116 		v.val = READ_ONCE(sk->sk_txrehash);
2117 		break;
2118 
2119 	default:
2120 		/* We implement the SO_SNDLOWAT etc to not be settable
2121 		 * (1003.1g 7).
2122 		 */
2123 		return -ENOPROTOOPT;
2124 	}
2125 
2126 	if (len > lv)
2127 		len = lv;
2128 	if (copy_to_sockptr(optval, &v, len))
2129 		return -EFAULT;
2130 lenout:
2131 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2132 		return -EFAULT;
2133 	return 0;
2134 }
2135 
2136 /*
2137  * Initialize an sk_lock.
2138  *
2139  * (We also register the sk_lock with the lock validator.)
2140  */
2141 static inline void sock_lock_init(struct sock *sk)
2142 {
2143 	if (sk->sk_kern_sock)
2144 		sock_lock_init_class_and_name(
2145 			sk,
2146 			af_family_kern_slock_key_strings[sk->sk_family],
2147 			af_family_kern_slock_keys + sk->sk_family,
2148 			af_family_kern_key_strings[sk->sk_family],
2149 			af_family_kern_keys + sk->sk_family);
2150 	else
2151 		sock_lock_init_class_and_name(
2152 			sk,
2153 			af_family_slock_key_strings[sk->sk_family],
2154 			af_family_slock_keys + sk->sk_family,
2155 			af_family_key_strings[sk->sk_family],
2156 			af_family_keys + sk->sk_family);
2157 }
2158 
2159 /*
2160  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2161  * even temporarily, because of RCU lookups. sk_node should also be left as is.
2162  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2163  */
2164 static void sock_copy(struct sock *nsk, const struct sock *osk)
2165 {
2166 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2167 #ifdef CONFIG_SECURITY_NETWORK
2168 	void *sptr = nsk->sk_security;
2169 #endif
2170 
2171 	/* If we move sk_tx_queue_mapping out of the private section,
2172 	 * we must check if sk_tx_queue_clear() is called after
2173 	 * sock_copy() in sk_clone_lock().
2174 	 */
2175 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2176 		     offsetof(struct sock, sk_dontcopy_begin) ||
2177 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2178 		     offsetof(struct sock, sk_dontcopy_end));
2179 
2180 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2181 
2182 	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2183 		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2184 		      /* alloc is larger than struct, see sk_prot_alloc() */);
2185 
2186 #ifdef CONFIG_SECURITY_NETWORK
2187 	nsk->sk_security = sptr;
2188 	security_sk_clone(osk, nsk);
2189 #endif
2190 }
2191 
2192 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2193 		int family)
2194 {
2195 	struct sock *sk;
2196 	struct kmem_cache *slab;
2197 
2198 	slab = prot->slab;
2199 	if (slab != NULL) {
2200 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2201 		if (!sk)
2202 			return sk;
2203 		if (want_init_on_alloc(priority))
2204 			sk_prot_clear_nulls(sk, prot->obj_size);
2205 	} else
2206 		sk = kmalloc(prot->obj_size, priority);
2207 
2208 	if (sk != NULL) {
2209 		if (security_sk_alloc(sk, family, priority))
2210 			goto out_free;
2211 
2212 		if (!try_module_get(prot->owner))
2213 			goto out_free_sec;
2214 	}
2215 
2216 	return sk;
2217 
2218 out_free_sec:
2219 	security_sk_free(sk);
2220 out_free:
2221 	if (slab != NULL)
2222 		kmem_cache_free(slab, sk);
2223 	else
2224 		kfree(sk);
2225 	return NULL;
2226 }
2227 
2228 static void sk_prot_free(struct proto *prot, struct sock *sk)
2229 {
2230 	struct kmem_cache *slab;
2231 	struct module *owner;
2232 
2233 	owner = prot->owner;
2234 	slab = prot->slab;
2235 
2236 	cgroup_sk_free(&sk->sk_cgrp_data);
2237 	mem_cgroup_sk_free(sk);
2238 	security_sk_free(sk);
2239 	if (slab != NULL)
2240 		kmem_cache_free(slab, sk);
2241 	else
2242 		kfree(sk);
2243 	module_put(owner);
2244 }
2245 
2246 /**
2247  *	sk_alloc - All socket objects are allocated here
2248  *	@net: the applicable net namespace
2249  *	@family: protocol family
2250  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2251  *	@prot: struct proto associated with this new sock instance
2252  *	@kern: is this to be a kernel socket?
2253  */
2254 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2255 		      struct proto *prot, int kern)
2256 {
2257 	struct sock *sk;
2258 
2259 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2260 	if (sk) {
2261 		sk->sk_family = family;
2262 		/*
2263 		 * See comment in struct sock definition to understand
2264 		 * why we need sk_prot_creator -acme
2265 		 */
2266 		sk->sk_prot = sk->sk_prot_creator = prot;
2267 		sk->sk_kern_sock = kern;
2268 		sock_lock_init(sk);
2269 		sk->sk_net_refcnt = kern ? 0 : 1;
2270 		if (likely(sk->sk_net_refcnt)) {
2271 			get_net_track(net, &sk->ns_tracker, priority);
2272 			sock_inuse_add(net, 1);
2273 		} else {
2274 			net_passive_inc(net);
2275 			__netns_tracker_alloc(net, &sk->ns_tracker,
2276 					      false, priority);
2277 		}
2278 
2279 		sock_net_set(sk, net);
2280 		refcount_set(&sk->sk_wmem_alloc, 1);
2281 
2282 		mem_cgroup_sk_alloc(sk);
2283 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2284 		sock_update_classid(&sk->sk_cgrp_data);
2285 		sock_update_netprioidx(&sk->sk_cgrp_data);
2286 		sk_tx_queue_clear(sk);
2287 	}
2288 
2289 	return sk;
2290 }
2291 EXPORT_SYMBOL(sk_alloc);
2292 
2293 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2294  * grace period. This is the case for UDP sockets and TCP listeners.
2295  */
2296 static void __sk_destruct(struct rcu_head *head)
2297 {
2298 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2299 	struct net *net = sock_net(sk);
2300 	struct sk_filter *filter;
2301 
2302 	if (sk->sk_destruct)
2303 		sk->sk_destruct(sk);
2304 
2305 	filter = rcu_dereference_check(sk->sk_filter,
2306 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2307 	if (filter) {
2308 		sk_filter_uncharge(sk, filter);
2309 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2310 	}
2311 
2312 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2313 
2314 #ifdef CONFIG_BPF_SYSCALL
2315 	bpf_sk_storage_free(sk);
2316 #endif
2317 
2318 	if (atomic_read(&sk->sk_omem_alloc))
2319 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2320 			 __func__, atomic_read(&sk->sk_omem_alloc));
2321 
2322 	if (sk->sk_frag.page) {
2323 		put_page(sk->sk_frag.page);
2324 		sk->sk_frag.page = NULL;
2325 	}
2326 
2327 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2328 	put_cred(sk->sk_peer_cred);
2329 	put_pid(sk->sk_peer_pid);
2330 
2331 	if (likely(sk->sk_net_refcnt)) {
2332 		put_net_track(net, &sk->ns_tracker);
2333 	} else {
2334 		__netns_tracker_free(net, &sk->ns_tracker, false);
2335 		net_passive_dec(net);
2336 	}
2337 	sk_prot_free(sk->sk_prot_creator, sk);
2338 }
2339 
2340 void sk_net_refcnt_upgrade(struct sock *sk)
2341 {
2342 	struct net *net = sock_net(sk);
2343 
2344 	WARN_ON_ONCE(sk->sk_net_refcnt);
2345 	__netns_tracker_free(net, &sk->ns_tracker, false);
2346 	net_passive_dec(net);
2347 	sk->sk_net_refcnt = 1;
2348 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2349 	sock_inuse_add(net, 1);
2350 }
2351 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2352 
2353 void sk_destruct(struct sock *sk)
2354 {
2355 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2356 
2357 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2358 		reuseport_detach_sock(sk);
2359 		use_call_rcu = true;
2360 	}
2361 
2362 	if (use_call_rcu)
2363 		call_rcu(&sk->sk_rcu, __sk_destruct);
2364 	else
2365 		__sk_destruct(&sk->sk_rcu);
2366 }
2367 
2368 static void __sk_free(struct sock *sk)
2369 {
2370 	if (likely(sk->sk_net_refcnt))
2371 		sock_inuse_add(sock_net(sk), -1);
2372 
2373 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2374 		sock_diag_broadcast_destroy(sk);
2375 	else
2376 		sk_destruct(sk);
2377 }
2378 
2379 void sk_free(struct sock *sk)
2380 {
2381 	/*
2382 	 * We subtract one from sk_wmem_alloc and can know if
2383 	 * some packets are still in some tx queue.
2384 	 * If not null, sock_wfree() will call __sk_free(sk) later
2385 	 */
2386 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2387 		__sk_free(sk);
2388 }
2389 EXPORT_SYMBOL(sk_free);
2390 
2391 static void sk_init_common(struct sock *sk)
2392 {
2393 	skb_queue_head_init(&sk->sk_receive_queue);
2394 	skb_queue_head_init(&sk->sk_write_queue);
2395 	skb_queue_head_init(&sk->sk_error_queue);
2396 
2397 	rwlock_init(&sk->sk_callback_lock);
2398 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2399 			af_rlock_keys + sk->sk_family,
2400 			af_family_rlock_key_strings[sk->sk_family]);
2401 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2402 			af_wlock_keys + sk->sk_family,
2403 			af_family_wlock_key_strings[sk->sk_family]);
2404 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2405 			af_elock_keys + sk->sk_family,
2406 			af_family_elock_key_strings[sk->sk_family]);
2407 	if (sk->sk_kern_sock)
2408 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2409 			af_kern_callback_keys + sk->sk_family,
2410 			af_family_kern_clock_key_strings[sk->sk_family]);
2411 	else
2412 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2413 			af_callback_keys + sk->sk_family,
2414 			af_family_clock_key_strings[sk->sk_family]);
2415 }
2416 
2417 /**
2418  *	sk_clone_lock - clone a socket, and lock its clone
2419  *	@sk: the socket to clone
2420  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2421  *
2422  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2423  */
2424 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2425 {
2426 	struct proto *prot = READ_ONCE(sk->sk_prot);
2427 	struct sk_filter *filter;
2428 	bool is_charged = true;
2429 	struct sock *newsk;
2430 
2431 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2432 	if (!newsk)
2433 		goto out;
2434 
2435 	sock_copy(newsk, sk);
2436 
2437 	newsk->sk_prot_creator = prot;
2438 
2439 	/* SANITY */
2440 	if (likely(newsk->sk_net_refcnt)) {
2441 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2442 		sock_inuse_add(sock_net(newsk), 1);
2443 	} else {
2444 		/* Kernel sockets are not elevating the struct net refcount.
2445 		 * Instead, use a tracker to more easily detect if a layer
2446 		 * is not properly dismantling its kernel sockets at netns
2447 		 * destroy time.
2448 		 */
2449 		net_passive_inc(sock_net(newsk));
2450 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2451 				      false, priority);
2452 	}
2453 	sk_node_init(&newsk->sk_node);
2454 	sock_lock_init(newsk);
2455 	bh_lock_sock(newsk);
2456 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2457 	newsk->sk_backlog.len = 0;
2458 
2459 	atomic_set(&newsk->sk_rmem_alloc, 0);
2460 
2461 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2462 	refcount_set(&newsk->sk_wmem_alloc, 1);
2463 
2464 	atomic_set(&newsk->sk_omem_alloc, 0);
2465 	sk_init_common(newsk);
2466 
2467 	newsk->sk_dst_cache	= NULL;
2468 	newsk->sk_dst_pending_confirm = 0;
2469 	newsk->sk_wmem_queued	= 0;
2470 	newsk->sk_forward_alloc = 0;
2471 	newsk->sk_reserved_mem  = 0;
2472 	atomic_set(&newsk->sk_drops, 0);
2473 	newsk->sk_send_head	= NULL;
2474 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2475 	atomic_set(&newsk->sk_zckey, 0);
2476 
2477 	sock_reset_flag(newsk, SOCK_DONE);
2478 
2479 	/* sk->sk_memcg will be populated at accept() time */
2480 	newsk->sk_memcg = NULL;
2481 
2482 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2483 
2484 	rcu_read_lock();
2485 	filter = rcu_dereference(sk->sk_filter);
2486 	if (filter != NULL)
2487 		/* though it's an empty new sock, the charging may fail
2488 		 * if sysctl_optmem_max was changed between creation of
2489 		 * original socket and cloning
2490 		 */
2491 		is_charged = sk_filter_charge(newsk, filter);
2492 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2493 	rcu_read_unlock();
2494 
2495 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2496 		/* We need to make sure that we don't uncharge the new
2497 		 * socket if we couldn't charge it in the first place
2498 		 * as otherwise we uncharge the parent's filter.
2499 		 */
2500 		if (!is_charged)
2501 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2502 		sk_free_unlock_clone(newsk);
2503 		newsk = NULL;
2504 		goto out;
2505 	}
2506 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2507 
2508 	if (bpf_sk_storage_clone(sk, newsk)) {
2509 		sk_free_unlock_clone(newsk);
2510 		newsk = NULL;
2511 		goto out;
2512 	}
2513 
2514 	/* Clear sk_user_data if parent had the pointer tagged
2515 	 * as not suitable for copying when cloning.
2516 	 */
2517 	if (sk_user_data_is_nocopy(newsk))
2518 		newsk->sk_user_data = NULL;
2519 
2520 	newsk->sk_err	   = 0;
2521 	newsk->sk_err_soft = 0;
2522 	newsk->sk_priority = 0;
2523 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2524 
2525 	/* Before updating sk_refcnt, we must commit prior changes to memory
2526 	 * (Documentation/RCU/rculist_nulls.rst for details)
2527 	 */
2528 	smp_wmb();
2529 	refcount_set(&newsk->sk_refcnt, 2);
2530 
2531 	sk_set_socket(newsk, NULL);
2532 	sk_tx_queue_clear(newsk);
2533 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2534 
2535 	if (newsk->sk_prot->sockets_allocated)
2536 		sk_sockets_allocated_inc(newsk);
2537 
2538 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2539 		net_enable_timestamp();
2540 out:
2541 	return newsk;
2542 }
2543 EXPORT_SYMBOL_GPL(sk_clone_lock);
2544 
2545 void sk_free_unlock_clone(struct sock *sk)
2546 {
2547 	/* It is still raw copy of parent, so invalidate
2548 	 * destructor and make plain sk_free() */
2549 	sk->sk_destruct = NULL;
2550 	bh_unlock_sock(sk);
2551 	sk_free(sk);
2552 }
2553 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2554 
2555 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2556 {
2557 	bool is_ipv6 = false;
2558 	u32 max_size;
2559 
2560 #if IS_ENABLED(CONFIG_IPV6)
2561 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2562 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2563 #endif
2564 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2565 	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2566 			READ_ONCE(dst->dev->gso_ipv4_max_size);
2567 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2568 		max_size = GSO_LEGACY_MAX_SIZE;
2569 
2570 	return max_size - (MAX_TCP_HEADER + 1);
2571 }
2572 
2573 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2574 {
2575 	u32 max_segs = 1;
2576 
2577 	sk->sk_route_caps = dst->dev->features;
2578 	if (sk_is_tcp(sk)) {
2579 		struct inet_connection_sock *icsk = inet_csk(sk);
2580 
2581 		sk->sk_route_caps |= NETIF_F_GSO;
2582 		icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2583 	}
2584 	if (sk->sk_route_caps & NETIF_F_GSO)
2585 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2586 	if (unlikely(sk->sk_gso_disabled))
2587 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2588 	if (sk_can_gso(sk)) {
2589 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2590 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2591 		} else {
2592 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2593 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2594 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2595 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2596 		}
2597 	}
2598 	sk->sk_gso_max_segs = max_segs;
2599 	sk_dst_set(sk, dst);
2600 }
2601 EXPORT_SYMBOL_GPL(sk_setup_caps);
2602 
2603 /*
2604  *	Simple resource managers for sockets.
2605  */
2606 
2607 
2608 /*
2609  * Write buffer destructor automatically called from kfree_skb.
2610  */
2611 void sock_wfree(struct sk_buff *skb)
2612 {
2613 	struct sock *sk = skb->sk;
2614 	unsigned int len = skb->truesize;
2615 	bool free;
2616 
2617 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2618 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2619 		    sk->sk_write_space == sock_def_write_space) {
2620 			rcu_read_lock();
2621 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2622 			sock_def_write_space_wfree(sk);
2623 			rcu_read_unlock();
2624 			if (unlikely(free))
2625 				__sk_free(sk);
2626 			return;
2627 		}
2628 
2629 		/*
2630 		 * Keep a reference on sk_wmem_alloc, this will be released
2631 		 * after sk_write_space() call
2632 		 */
2633 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2634 		sk->sk_write_space(sk);
2635 		len = 1;
2636 	}
2637 	/*
2638 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2639 	 * could not do because of in-flight packets
2640 	 */
2641 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2642 		__sk_free(sk);
2643 }
2644 EXPORT_SYMBOL(sock_wfree);
2645 
2646 /* This variant of sock_wfree() is used by TCP,
2647  * since it sets SOCK_USE_WRITE_QUEUE.
2648  */
2649 void __sock_wfree(struct sk_buff *skb)
2650 {
2651 	struct sock *sk = skb->sk;
2652 
2653 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2654 		__sk_free(sk);
2655 }
2656 
2657 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2658 {
2659 	skb_orphan(skb);
2660 #ifdef CONFIG_INET
2661 	if (unlikely(!sk_fullsock(sk)))
2662 		return skb_set_owner_edemux(skb, sk);
2663 #endif
2664 	skb->sk = sk;
2665 	skb->destructor = sock_wfree;
2666 	skb_set_hash_from_sk(skb, sk);
2667 	/*
2668 	 * We used to take a refcount on sk, but following operation
2669 	 * is enough to guarantee sk_free() won't free this sock until
2670 	 * all in-flight packets are completed
2671 	 */
2672 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2673 }
2674 EXPORT_SYMBOL(skb_set_owner_w);
2675 
2676 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2677 {
2678 	/* Drivers depend on in-order delivery for crypto offload,
2679 	 * partial orphan breaks out-of-order-OK logic.
2680 	 */
2681 	if (skb_is_decrypted(skb))
2682 		return false;
2683 
2684 	return (skb->destructor == sock_wfree ||
2685 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2686 }
2687 
2688 /* This helper is used by netem, as it can hold packets in its
2689  * delay queue. We want to allow the owner socket to send more
2690  * packets, as if they were already TX completed by a typical driver.
2691  * But we also want to keep skb->sk set because some packet schedulers
2692  * rely on it (sch_fq for example).
2693  */
2694 void skb_orphan_partial(struct sk_buff *skb)
2695 {
2696 	if (skb_is_tcp_pure_ack(skb))
2697 		return;
2698 
2699 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2700 		return;
2701 
2702 	skb_orphan(skb);
2703 }
2704 EXPORT_SYMBOL(skb_orphan_partial);
2705 
2706 /*
2707  * Read buffer destructor automatically called from kfree_skb.
2708  */
2709 void sock_rfree(struct sk_buff *skb)
2710 {
2711 	struct sock *sk = skb->sk;
2712 	unsigned int len = skb->truesize;
2713 
2714 	atomic_sub(len, &sk->sk_rmem_alloc);
2715 	sk_mem_uncharge(sk, len);
2716 }
2717 EXPORT_SYMBOL(sock_rfree);
2718 
2719 /*
2720  * Buffer destructor for skbs that are not used directly in read or write
2721  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2722  */
2723 void sock_efree(struct sk_buff *skb)
2724 {
2725 	sock_put(skb->sk);
2726 }
2727 EXPORT_SYMBOL(sock_efree);
2728 
2729 /* Buffer destructor for prefetch/receive path where reference count may
2730  * not be held, e.g. for listen sockets.
2731  */
2732 #ifdef CONFIG_INET
2733 void sock_pfree(struct sk_buff *skb)
2734 {
2735 	struct sock *sk = skb->sk;
2736 
2737 	if (!sk_is_refcounted(sk))
2738 		return;
2739 
2740 	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2741 		inet_reqsk(sk)->rsk_listener = NULL;
2742 		reqsk_free(inet_reqsk(sk));
2743 		return;
2744 	}
2745 
2746 	sock_gen_put(sk);
2747 }
2748 EXPORT_SYMBOL(sock_pfree);
2749 #endif /* CONFIG_INET */
2750 
2751 kuid_t sock_i_uid(struct sock *sk)
2752 {
2753 	kuid_t uid;
2754 
2755 	read_lock_bh(&sk->sk_callback_lock);
2756 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2757 	read_unlock_bh(&sk->sk_callback_lock);
2758 	return uid;
2759 }
2760 EXPORT_SYMBOL(sock_i_uid);
2761 
2762 unsigned long __sock_i_ino(struct sock *sk)
2763 {
2764 	unsigned long ino;
2765 
2766 	read_lock(&sk->sk_callback_lock);
2767 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2768 	read_unlock(&sk->sk_callback_lock);
2769 	return ino;
2770 }
2771 EXPORT_SYMBOL(__sock_i_ino);
2772 
2773 unsigned long sock_i_ino(struct sock *sk)
2774 {
2775 	unsigned long ino;
2776 
2777 	local_bh_disable();
2778 	ino = __sock_i_ino(sk);
2779 	local_bh_enable();
2780 	return ino;
2781 }
2782 EXPORT_SYMBOL(sock_i_ino);
2783 
2784 /*
2785  * Allocate a skb from the socket's send buffer.
2786  */
2787 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2788 			     gfp_t priority)
2789 {
2790 	if (force ||
2791 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2792 		struct sk_buff *skb = alloc_skb(size, priority);
2793 
2794 		if (skb) {
2795 			skb_set_owner_w(skb, sk);
2796 			return skb;
2797 		}
2798 	}
2799 	return NULL;
2800 }
2801 EXPORT_SYMBOL(sock_wmalloc);
2802 
2803 static void sock_ofree(struct sk_buff *skb)
2804 {
2805 	struct sock *sk = skb->sk;
2806 
2807 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2808 }
2809 
2810 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2811 			     gfp_t priority)
2812 {
2813 	struct sk_buff *skb;
2814 
2815 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2816 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2817 	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2818 		return NULL;
2819 
2820 	skb = alloc_skb(size, priority);
2821 	if (!skb)
2822 		return NULL;
2823 
2824 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2825 	skb->sk = sk;
2826 	skb->destructor = sock_ofree;
2827 	return skb;
2828 }
2829 
2830 /*
2831  * Allocate a memory block from the socket's option memory buffer.
2832  */
2833 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2834 {
2835 	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2836 
2837 	if ((unsigned int)size <= optmem_max &&
2838 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2839 		void *mem;
2840 		/* First do the add, to avoid the race if kmalloc
2841 		 * might sleep.
2842 		 */
2843 		atomic_add(size, &sk->sk_omem_alloc);
2844 		mem = kmalloc(size, priority);
2845 		if (mem)
2846 			return mem;
2847 		atomic_sub(size, &sk->sk_omem_alloc);
2848 	}
2849 	return NULL;
2850 }
2851 EXPORT_SYMBOL(sock_kmalloc);
2852 
2853 /*
2854  * Duplicate the input "src" memory block using the socket's
2855  * option memory buffer.
2856  */
2857 void *sock_kmemdup(struct sock *sk, const void *src,
2858 		   int size, gfp_t priority)
2859 {
2860 	void *mem;
2861 
2862 	mem = sock_kmalloc(sk, size, priority);
2863 	if (mem)
2864 		memcpy(mem, src, size);
2865 	return mem;
2866 }
2867 EXPORT_SYMBOL(sock_kmemdup);
2868 
2869 /* Free an option memory block. Note, we actually want the inline
2870  * here as this allows gcc to detect the nullify and fold away the
2871  * condition entirely.
2872  */
2873 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2874 				  const bool nullify)
2875 {
2876 	if (WARN_ON_ONCE(!mem))
2877 		return;
2878 	if (nullify)
2879 		kfree_sensitive(mem);
2880 	else
2881 		kfree(mem);
2882 	atomic_sub(size, &sk->sk_omem_alloc);
2883 }
2884 
2885 void sock_kfree_s(struct sock *sk, void *mem, int size)
2886 {
2887 	__sock_kfree_s(sk, mem, size, false);
2888 }
2889 EXPORT_SYMBOL(sock_kfree_s);
2890 
2891 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2892 {
2893 	__sock_kfree_s(sk, mem, size, true);
2894 }
2895 EXPORT_SYMBOL(sock_kzfree_s);
2896 
2897 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2898    I think, these locks should be removed for datagram sockets.
2899  */
2900 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2901 {
2902 	DEFINE_WAIT(wait);
2903 
2904 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2905 	for (;;) {
2906 		if (!timeo)
2907 			break;
2908 		if (signal_pending(current))
2909 			break;
2910 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2911 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2912 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2913 			break;
2914 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2915 			break;
2916 		if (READ_ONCE(sk->sk_err))
2917 			break;
2918 		timeo = schedule_timeout(timeo);
2919 	}
2920 	finish_wait(sk_sleep(sk), &wait);
2921 	return timeo;
2922 }
2923 
2924 
2925 /*
2926  *	Generic send/receive buffer handlers
2927  */
2928 
2929 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2930 				     unsigned long data_len, int noblock,
2931 				     int *errcode, int max_page_order)
2932 {
2933 	struct sk_buff *skb;
2934 	long timeo;
2935 	int err;
2936 
2937 	timeo = sock_sndtimeo(sk, noblock);
2938 	for (;;) {
2939 		err = sock_error(sk);
2940 		if (err != 0)
2941 			goto failure;
2942 
2943 		err = -EPIPE;
2944 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2945 			goto failure;
2946 
2947 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2948 			break;
2949 
2950 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2951 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2952 		err = -EAGAIN;
2953 		if (!timeo)
2954 			goto failure;
2955 		if (signal_pending(current))
2956 			goto interrupted;
2957 		timeo = sock_wait_for_wmem(sk, timeo);
2958 	}
2959 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2960 				   errcode, sk->sk_allocation);
2961 	if (skb)
2962 		skb_set_owner_w(skb, sk);
2963 	return skb;
2964 
2965 interrupted:
2966 	err = sock_intr_errno(timeo);
2967 failure:
2968 	*errcode = err;
2969 	return NULL;
2970 }
2971 EXPORT_SYMBOL(sock_alloc_send_pskb);
2972 
2973 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2974 		     struct sockcm_cookie *sockc)
2975 {
2976 	u32 tsflags;
2977 
2978 	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
2979 
2980 	switch (cmsg->cmsg_type) {
2981 	case SO_MARK:
2982 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2983 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2984 			return -EPERM;
2985 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2986 			return -EINVAL;
2987 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2988 		break;
2989 	case SO_TIMESTAMPING_OLD:
2990 	case SO_TIMESTAMPING_NEW:
2991 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2992 			return -EINVAL;
2993 
2994 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2995 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2996 			return -EINVAL;
2997 
2998 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2999 		sockc->tsflags |= tsflags;
3000 		break;
3001 	case SCM_TXTIME:
3002 		if (!sock_flag(sk, SOCK_TXTIME))
3003 			return -EINVAL;
3004 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3005 			return -EINVAL;
3006 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
3007 		break;
3008 	case SCM_TS_OPT_ID:
3009 		if (sk_is_tcp(sk))
3010 			return -EINVAL;
3011 		tsflags = READ_ONCE(sk->sk_tsflags);
3012 		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3013 			return -EINVAL;
3014 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3015 			return -EINVAL;
3016 		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3017 		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3018 		break;
3019 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3020 	case SCM_RIGHTS:
3021 	case SCM_CREDENTIALS:
3022 		break;
3023 	case SO_PRIORITY:
3024 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3025 			return -EINVAL;
3026 		if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3027 			return -EPERM;
3028 		sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3029 		break;
3030 	default:
3031 		return -EINVAL;
3032 	}
3033 	return 0;
3034 }
3035 EXPORT_SYMBOL(__sock_cmsg_send);
3036 
3037 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3038 		   struct sockcm_cookie *sockc)
3039 {
3040 	struct cmsghdr *cmsg;
3041 	int ret;
3042 
3043 	for_each_cmsghdr(cmsg, msg) {
3044 		if (!CMSG_OK(msg, cmsg))
3045 			return -EINVAL;
3046 		if (cmsg->cmsg_level != SOL_SOCKET)
3047 			continue;
3048 		ret = __sock_cmsg_send(sk, cmsg, sockc);
3049 		if (ret)
3050 			return ret;
3051 	}
3052 	return 0;
3053 }
3054 EXPORT_SYMBOL(sock_cmsg_send);
3055 
3056 static void sk_enter_memory_pressure(struct sock *sk)
3057 {
3058 	if (!sk->sk_prot->enter_memory_pressure)
3059 		return;
3060 
3061 	sk->sk_prot->enter_memory_pressure(sk);
3062 }
3063 
3064 static void sk_leave_memory_pressure(struct sock *sk)
3065 {
3066 	if (sk->sk_prot->leave_memory_pressure) {
3067 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3068 				     tcp_leave_memory_pressure, sk);
3069 	} else {
3070 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3071 
3072 		if (memory_pressure && READ_ONCE(*memory_pressure))
3073 			WRITE_ONCE(*memory_pressure, 0);
3074 	}
3075 }
3076 
3077 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3078 
3079 /**
3080  * skb_page_frag_refill - check that a page_frag contains enough room
3081  * @sz: minimum size of the fragment we want to get
3082  * @pfrag: pointer to page_frag
3083  * @gfp: priority for memory allocation
3084  *
3085  * Note: While this allocator tries to use high order pages, there is
3086  * no guarantee that allocations succeed. Therefore, @sz MUST be
3087  * less or equal than PAGE_SIZE.
3088  */
3089 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3090 {
3091 	if (pfrag->page) {
3092 		if (page_ref_count(pfrag->page) == 1) {
3093 			pfrag->offset = 0;
3094 			return true;
3095 		}
3096 		if (pfrag->offset + sz <= pfrag->size)
3097 			return true;
3098 		put_page(pfrag->page);
3099 	}
3100 
3101 	pfrag->offset = 0;
3102 	if (SKB_FRAG_PAGE_ORDER &&
3103 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3104 		/* Avoid direct reclaim but allow kswapd to wake */
3105 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3106 					  __GFP_COMP | __GFP_NOWARN |
3107 					  __GFP_NORETRY,
3108 					  SKB_FRAG_PAGE_ORDER);
3109 		if (likely(pfrag->page)) {
3110 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3111 			return true;
3112 		}
3113 	}
3114 	pfrag->page = alloc_page(gfp);
3115 	if (likely(pfrag->page)) {
3116 		pfrag->size = PAGE_SIZE;
3117 		return true;
3118 	}
3119 	return false;
3120 }
3121 EXPORT_SYMBOL(skb_page_frag_refill);
3122 
3123 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3124 {
3125 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3126 		return true;
3127 
3128 	sk_enter_memory_pressure(sk);
3129 	sk_stream_moderate_sndbuf(sk);
3130 	return false;
3131 }
3132 EXPORT_SYMBOL(sk_page_frag_refill);
3133 
3134 void __lock_sock(struct sock *sk)
3135 	__releases(&sk->sk_lock.slock)
3136 	__acquires(&sk->sk_lock.slock)
3137 {
3138 	DEFINE_WAIT(wait);
3139 
3140 	for (;;) {
3141 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3142 					TASK_UNINTERRUPTIBLE);
3143 		spin_unlock_bh(&sk->sk_lock.slock);
3144 		schedule();
3145 		spin_lock_bh(&sk->sk_lock.slock);
3146 		if (!sock_owned_by_user(sk))
3147 			break;
3148 	}
3149 	finish_wait(&sk->sk_lock.wq, &wait);
3150 }
3151 
3152 void __release_sock(struct sock *sk)
3153 	__releases(&sk->sk_lock.slock)
3154 	__acquires(&sk->sk_lock.slock)
3155 {
3156 	struct sk_buff *skb, *next;
3157 
3158 	while ((skb = sk->sk_backlog.head) != NULL) {
3159 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3160 
3161 		spin_unlock_bh(&sk->sk_lock.slock);
3162 
3163 		do {
3164 			next = skb->next;
3165 			prefetch(next);
3166 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3167 			skb_mark_not_on_list(skb);
3168 			sk_backlog_rcv(sk, skb);
3169 
3170 			cond_resched();
3171 
3172 			skb = next;
3173 		} while (skb != NULL);
3174 
3175 		spin_lock_bh(&sk->sk_lock.slock);
3176 	}
3177 
3178 	/*
3179 	 * Doing the zeroing here guarantee we can not loop forever
3180 	 * while a wild producer attempts to flood us.
3181 	 */
3182 	sk->sk_backlog.len = 0;
3183 }
3184 
3185 void __sk_flush_backlog(struct sock *sk)
3186 {
3187 	spin_lock_bh(&sk->sk_lock.slock);
3188 	__release_sock(sk);
3189 
3190 	if (sk->sk_prot->release_cb)
3191 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3192 				     tcp_release_cb, sk);
3193 
3194 	spin_unlock_bh(&sk->sk_lock.slock);
3195 }
3196 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3197 
3198 /**
3199  * sk_wait_data - wait for data to arrive at sk_receive_queue
3200  * @sk:    sock to wait on
3201  * @timeo: for how long
3202  * @skb:   last skb seen on sk_receive_queue
3203  *
3204  * Now socket state including sk->sk_err is changed only under lock,
3205  * hence we may omit checks after joining wait queue.
3206  * We check receive queue before schedule() only as optimization;
3207  * it is very likely that release_sock() added new data.
3208  */
3209 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3210 {
3211 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3212 	int rc;
3213 
3214 	add_wait_queue(sk_sleep(sk), &wait);
3215 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3216 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3217 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3218 	remove_wait_queue(sk_sleep(sk), &wait);
3219 	return rc;
3220 }
3221 EXPORT_SYMBOL(sk_wait_data);
3222 
3223 /**
3224  *	__sk_mem_raise_allocated - increase memory_allocated
3225  *	@sk: socket
3226  *	@size: memory size to allocate
3227  *	@amt: pages to allocate
3228  *	@kind: allocation type
3229  *
3230  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3231  *
3232  *	Unlike the globally shared limits among the sockets under same protocol,
3233  *	consuming the budget of a memcg won't have direct effect on other ones.
3234  *	So be optimistic about memcg's tolerance, and leave the callers to decide
3235  *	whether or not to raise allocated through sk_under_memory_pressure() or
3236  *	its variants.
3237  */
3238 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3239 {
3240 	struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3241 	struct proto *prot = sk->sk_prot;
3242 	bool charged = false;
3243 	long allocated;
3244 
3245 	sk_memory_allocated_add(sk, amt);
3246 	allocated = sk_memory_allocated(sk);
3247 
3248 	if (memcg) {
3249 		if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3250 			goto suppress_allocation;
3251 		charged = true;
3252 	}
3253 
3254 	/* Under limit. */
3255 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3256 		sk_leave_memory_pressure(sk);
3257 		return 1;
3258 	}
3259 
3260 	/* Under pressure. */
3261 	if (allocated > sk_prot_mem_limits(sk, 1))
3262 		sk_enter_memory_pressure(sk);
3263 
3264 	/* Over hard limit. */
3265 	if (allocated > sk_prot_mem_limits(sk, 2))
3266 		goto suppress_allocation;
3267 
3268 	/* Guarantee minimum buffer size under pressure (either global
3269 	 * or memcg) to make sure features described in RFC 7323 (TCP
3270 	 * Extensions for High Performance) work properly.
3271 	 *
3272 	 * This rule does NOT stand when exceeds global or memcg's hard
3273 	 * limit, or else a DoS attack can be taken place by spawning
3274 	 * lots of sockets whose usage are under minimum buffer size.
3275 	 */
3276 	if (kind == SK_MEM_RECV) {
3277 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3278 			return 1;
3279 
3280 	} else { /* SK_MEM_SEND */
3281 		int wmem0 = sk_get_wmem0(sk, prot);
3282 
3283 		if (sk->sk_type == SOCK_STREAM) {
3284 			if (sk->sk_wmem_queued < wmem0)
3285 				return 1;
3286 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3287 				return 1;
3288 		}
3289 	}
3290 
3291 	if (sk_has_memory_pressure(sk)) {
3292 		u64 alloc;
3293 
3294 		/* The following 'average' heuristic is within the
3295 		 * scope of global accounting, so it only makes
3296 		 * sense for global memory pressure.
3297 		 */
3298 		if (!sk_under_global_memory_pressure(sk))
3299 			return 1;
3300 
3301 		/* Try to be fair among all the sockets under global
3302 		 * pressure by allowing the ones that below average
3303 		 * usage to raise.
3304 		 */
3305 		alloc = sk_sockets_allocated_read_positive(sk);
3306 		if (sk_prot_mem_limits(sk, 2) > alloc *
3307 		    sk_mem_pages(sk->sk_wmem_queued +
3308 				 atomic_read(&sk->sk_rmem_alloc) +
3309 				 sk->sk_forward_alloc))
3310 			return 1;
3311 	}
3312 
3313 suppress_allocation:
3314 
3315 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3316 		sk_stream_moderate_sndbuf(sk);
3317 
3318 		/* Fail only if socket is _under_ its sndbuf.
3319 		 * In this case we cannot block, so that we have to fail.
3320 		 */
3321 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3322 			/* Force charge with __GFP_NOFAIL */
3323 			if (memcg && !charged) {
3324 				mem_cgroup_charge_skmem(memcg, amt,
3325 					gfp_memcg_charge() | __GFP_NOFAIL);
3326 			}
3327 			return 1;
3328 		}
3329 	}
3330 
3331 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3332 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3333 
3334 	sk_memory_allocated_sub(sk, amt);
3335 
3336 	if (charged)
3337 		mem_cgroup_uncharge_skmem(memcg, amt);
3338 
3339 	return 0;
3340 }
3341 
3342 /**
3343  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3344  *	@sk: socket
3345  *	@size: memory size to allocate
3346  *	@kind: allocation type
3347  *
3348  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3349  *	rmem allocation. This function assumes that protocols which have
3350  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3351  */
3352 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3353 {
3354 	int ret, amt = sk_mem_pages(size);
3355 
3356 	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3357 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3358 	if (!ret)
3359 		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3360 	return ret;
3361 }
3362 EXPORT_SYMBOL(__sk_mem_schedule);
3363 
3364 /**
3365  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3366  *	@sk: socket
3367  *	@amount: number of quanta
3368  *
3369  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3370  */
3371 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3372 {
3373 	sk_memory_allocated_sub(sk, amount);
3374 
3375 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3376 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3377 
3378 	if (sk_under_global_memory_pressure(sk) &&
3379 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3380 		sk_leave_memory_pressure(sk);
3381 }
3382 
3383 /**
3384  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3385  *	@sk: socket
3386  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3387  */
3388 void __sk_mem_reclaim(struct sock *sk, int amount)
3389 {
3390 	amount >>= PAGE_SHIFT;
3391 	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3392 	__sk_mem_reduce_allocated(sk, amount);
3393 }
3394 EXPORT_SYMBOL(__sk_mem_reclaim);
3395 
3396 int sk_set_peek_off(struct sock *sk, int val)
3397 {
3398 	WRITE_ONCE(sk->sk_peek_off, val);
3399 	return 0;
3400 }
3401 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3402 
3403 /*
3404  * Set of default routines for initialising struct proto_ops when
3405  * the protocol does not support a particular function. In certain
3406  * cases where it makes no sense for a protocol to have a "do nothing"
3407  * function, some default processing is provided.
3408  */
3409 
3410 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3411 {
3412 	return -EOPNOTSUPP;
3413 }
3414 EXPORT_SYMBOL(sock_no_bind);
3415 
3416 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3417 		    int len, int flags)
3418 {
3419 	return -EOPNOTSUPP;
3420 }
3421 EXPORT_SYMBOL(sock_no_connect);
3422 
3423 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3424 {
3425 	return -EOPNOTSUPP;
3426 }
3427 EXPORT_SYMBOL(sock_no_socketpair);
3428 
3429 int sock_no_accept(struct socket *sock, struct socket *newsock,
3430 		   struct proto_accept_arg *arg)
3431 {
3432 	return -EOPNOTSUPP;
3433 }
3434 EXPORT_SYMBOL(sock_no_accept);
3435 
3436 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3437 		    int peer)
3438 {
3439 	return -EOPNOTSUPP;
3440 }
3441 EXPORT_SYMBOL(sock_no_getname);
3442 
3443 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3444 {
3445 	return -EOPNOTSUPP;
3446 }
3447 EXPORT_SYMBOL(sock_no_ioctl);
3448 
3449 int sock_no_listen(struct socket *sock, int backlog)
3450 {
3451 	return -EOPNOTSUPP;
3452 }
3453 EXPORT_SYMBOL(sock_no_listen);
3454 
3455 int sock_no_shutdown(struct socket *sock, int how)
3456 {
3457 	return -EOPNOTSUPP;
3458 }
3459 EXPORT_SYMBOL(sock_no_shutdown);
3460 
3461 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3462 {
3463 	return -EOPNOTSUPP;
3464 }
3465 EXPORT_SYMBOL(sock_no_sendmsg);
3466 
3467 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3468 {
3469 	return -EOPNOTSUPP;
3470 }
3471 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3472 
3473 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3474 		    int flags)
3475 {
3476 	return -EOPNOTSUPP;
3477 }
3478 EXPORT_SYMBOL(sock_no_recvmsg);
3479 
3480 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3481 {
3482 	/* Mirror missing mmap method error code */
3483 	return -ENODEV;
3484 }
3485 EXPORT_SYMBOL(sock_no_mmap);
3486 
3487 /*
3488  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3489  * various sock-based usage counts.
3490  */
3491 void __receive_sock(struct file *file)
3492 {
3493 	struct socket *sock;
3494 
3495 	sock = sock_from_file(file);
3496 	if (sock) {
3497 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3498 		sock_update_classid(&sock->sk->sk_cgrp_data);
3499 	}
3500 }
3501 
3502 /*
3503  *	Default Socket Callbacks
3504  */
3505 
3506 static void sock_def_wakeup(struct sock *sk)
3507 {
3508 	struct socket_wq *wq;
3509 
3510 	rcu_read_lock();
3511 	wq = rcu_dereference(sk->sk_wq);
3512 	if (skwq_has_sleeper(wq))
3513 		wake_up_interruptible_all(&wq->wait);
3514 	rcu_read_unlock();
3515 }
3516 
3517 static void sock_def_error_report(struct sock *sk)
3518 {
3519 	struct socket_wq *wq;
3520 
3521 	rcu_read_lock();
3522 	wq = rcu_dereference(sk->sk_wq);
3523 	if (skwq_has_sleeper(wq))
3524 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3525 	sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3526 	rcu_read_unlock();
3527 }
3528 
3529 void sock_def_readable(struct sock *sk)
3530 {
3531 	struct socket_wq *wq;
3532 
3533 	trace_sk_data_ready(sk);
3534 
3535 	rcu_read_lock();
3536 	wq = rcu_dereference(sk->sk_wq);
3537 	if (skwq_has_sleeper(wq))
3538 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3539 						EPOLLRDNORM | EPOLLRDBAND);
3540 	sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3541 	rcu_read_unlock();
3542 }
3543 
3544 static void sock_def_write_space(struct sock *sk)
3545 {
3546 	struct socket_wq *wq;
3547 
3548 	rcu_read_lock();
3549 
3550 	/* Do not wake up a writer until he can make "significant"
3551 	 * progress.  --DaveM
3552 	 */
3553 	if (sock_writeable(sk)) {
3554 		wq = rcu_dereference(sk->sk_wq);
3555 		if (skwq_has_sleeper(wq))
3556 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3557 						EPOLLWRNORM | EPOLLWRBAND);
3558 
3559 		/* Should agree with poll, otherwise some programs break */
3560 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3561 	}
3562 
3563 	rcu_read_unlock();
3564 }
3565 
3566 /* An optimised version of sock_def_write_space(), should only be called
3567  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3568  * ->sk_wmem_alloc.
3569  */
3570 static void sock_def_write_space_wfree(struct sock *sk)
3571 {
3572 	/* Do not wake up a writer until he can make "significant"
3573 	 * progress.  --DaveM
3574 	 */
3575 	if (sock_writeable(sk)) {
3576 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3577 
3578 		/* rely on refcount_sub from sock_wfree() */
3579 		smp_mb__after_atomic();
3580 		if (wq && waitqueue_active(&wq->wait))
3581 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3582 						EPOLLWRNORM | EPOLLWRBAND);
3583 
3584 		/* Should agree with poll, otherwise some programs break */
3585 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3586 	}
3587 }
3588 
3589 static void sock_def_destruct(struct sock *sk)
3590 {
3591 }
3592 
3593 void sk_send_sigurg(struct sock *sk)
3594 {
3595 	if (sk->sk_socket && sk->sk_socket->file)
3596 		if (send_sigurg(sk->sk_socket->file))
3597 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3598 }
3599 EXPORT_SYMBOL(sk_send_sigurg);
3600 
3601 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3602 		    unsigned long expires)
3603 {
3604 	if (!mod_timer(timer, expires))
3605 		sock_hold(sk);
3606 }
3607 EXPORT_SYMBOL(sk_reset_timer);
3608 
3609 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3610 {
3611 	if (timer_delete(timer))
3612 		__sock_put(sk);
3613 }
3614 EXPORT_SYMBOL(sk_stop_timer);
3615 
3616 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3617 {
3618 	if (timer_delete_sync(timer))
3619 		__sock_put(sk);
3620 }
3621 EXPORT_SYMBOL(sk_stop_timer_sync);
3622 
3623 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3624 {
3625 	sk_init_common(sk);
3626 	sk->sk_send_head	=	NULL;
3627 
3628 	timer_setup(&sk->sk_timer, NULL, 0);
3629 
3630 	sk->sk_allocation	=	GFP_KERNEL;
3631 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3632 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3633 	sk->sk_state		=	TCP_CLOSE;
3634 	sk->sk_use_task_frag	=	true;
3635 	sk_set_socket(sk, sock);
3636 
3637 	sock_set_flag(sk, SOCK_ZAPPED);
3638 
3639 	if (sock) {
3640 		sk->sk_type	=	sock->type;
3641 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3642 		sock->sk	=	sk;
3643 	} else {
3644 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3645 	}
3646 	sk->sk_uid	=	uid;
3647 
3648 	sk->sk_state_change	=	sock_def_wakeup;
3649 	sk->sk_data_ready	=	sock_def_readable;
3650 	sk->sk_write_space	=	sock_def_write_space;
3651 	sk->sk_error_report	=	sock_def_error_report;
3652 	sk->sk_destruct		=	sock_def_destruct;
3653 
3654 	sk->sk_frag.page	=	NULL;
3655 	sk->sk_frag.offset	=	0;
3656 	sk->sk_peek_off		=	-1;
3657 
3658 	sk->sk_peer_pid 	=	NULL;
3659 	sk->sk_peer_cred	=	NULL;
3660 	spin_lock_init(&sk->sk_peer_lock);
3661 
3662 	sk->sk_write_pending	=	0;
3663 	sk->sk_rcvlowat		=	1;
3664 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3665 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3666 
3667 	sk->sk_stamp = SK_DEFAULT_STAMP;
3668 #if BITS_PER_LONG==32
3669 	seqlock_init(&sk->sk_stamp_seq);
3670 #endif
3671 	atomic_set(&sk->sk_zckey, 0);
3672 
3673 #ifdef CONFIG_NET_RX_BUSY_POLL
3674 	sk->sk_napi_id		=	0;
3675 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3676 #endif
3677 
3678 	sk->sk_max_pacing_rate = ~0UL;
3679 	sk->sk_pacing_rate = ~0UL;
3680 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3681 	sk->sk_incoming_cpu = -1;
3682 
3683 	sk_rx_queue_clear(sk);
3684 	/*
3685 	 * Before updating sk_refcnt, we must commit prior changes to memory
3686 	 * (Documentation/RCU/rculist_nulls.rst for details)
3687 	 */
3688 	smp_wmb();
3689 	refcount_set(&sk->sk_refcnt, 1);
3690 	atomic_set(&sk->sk_drops, 0);
3691 }
3692 EXPORT_SYMBOL(sock_init_data_uid);
3693 
3694 void sock_init_data(struct socket *sock, struct sock *sk)
3695 {
3696 	kuid_t uid = sock ?
3697 		SOCK_INODE(sock)->i_uid :
3698 		make_kuid(sock_net(sk)->user_ns, 0);
3699 
3700 	sock_init_data_uid(sock, sk, uid);
3701 }
3702 EXPORT_SYMBOL(sock_init_data);
3703 
3704 void lock_sock_nested(struct sock *sk, int subclass)
3705 {
3706 	/* The sk_lock has mutex_lock() semantics here. */
3707 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3708 
3709 	might_sleep();
3710 	spin_lock_bh(&sk->sk_lock.slock);
3711 	if (sock_owned_by_user_nocheck(sk))
3712 		__lock_sock(sk);
3713 	sk->sk_lock.owned = 1;
3714 	spin_unlock_bh(&sk->sk_lock.slock);
3715 }
3716 EXPORT_SYMBOL(lock_sock_nested);
3717 
3718 void release_sock(struct sock *sk)
3719 {
3720 	spin_lock_bh(&sk->sk_lock.slock);
3721 	if (sk->sk_backlog.tail)
3722 		__release_sock(sk);
3723 
3724 	if (sk->sk_prot->release_cb)
3725 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3726 				     tcp_release_cb, sk);
3727 
3728 	sock_release_ownership(sk);
3729 	if (waitqueue_active(&sk->sk_lock.wq))
3730 		wake_up(&sk->sk_lock.wq);
3731 	spin_unlock_bh(&sk->sk_lock.slock);
3732 }
3733 EXPORT_SYMBOL(release_sock);
3734 
3735 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3736 {
3737 	might_sleep();
3738 	spin_lock_bh(&sk->sk_lock.slock);
3739 
3740 	if (!sock_owned_by_user_nocheck(sk)) {
3741 		/*
3742 		 * Fast path return with bottom halves disabled and
3743 		 * sock::sk_lock.slock held.
3744 		 *
3745 		 * The 'mutex' is not contended and holding
3746 		 * sock::sk_lock.slock prevents all other lockers to
3747 		 * proceed so the corresponding unlock_sock_fast() can
3748 		 * avoid the slow path of release_sock() completely and
3749 		 * just release slock.
3750 		 *
3751 		 * From a semantical POV this is equivalent to 'acquiring'
3752 		 * the 'mutex', hence the corresponding lockdep
3753 		 * mutex_release() has to happen in the fast path of
3754 		 * unlock_sock_fast().
3755 		 */
3756 		return false;
3757 	}
3758 
3759 	__lock_sock(sk);
3760 	sk->sk_lock.owned = 1;
3761 	__acquire(&sk->sk_lock.slock);
3762 	spin_unlock_bh(&sk->sk_lock.slock);
3763 	return true;
3764 }
3765 EXPORT_SYMBOL(__lock_sock_fast);
3766 
3767 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3768 		   bool timeval, bool time32)
3769 {
3770 	struct sock *sk = sock->sk;
3771 	struct timespec64 ts;
3772 
3773 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3774 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3775 	if (ts.tv_sec == -1)
3776 		return -ENOENT;
3777 	if (ts.tv_sec == 0) {
3778 		ktime_t kt = ktime_get_real();
3779 		sock_write_timestamp(sk, kt);
3780 		ts = ktime_to_timespec64(kt);
3781 	}
3782 
3783 	if (timeval)
3784 		ts.tv_nsec /= 1000;
3785 
3786 #ifdef CONFIG_COMPAT_32BIT_TIME
3787 	if (time32)
3788 		return put_old_timespec32(&ts, userstamp);
3789 #endif
3790 #ifdef CONFIG_SPARC64
3791 	/* beware of padding in sparc64 timeval */
3792 	if (timeval && !in_compat_syscall()) {
3793 		struct __kernel_old_timeval __user tv = {
3794 			.tv_sec = ts.tv_sec,
3795 			.tv_usec = ts.tv_nsec,
3796 		};
3797 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3798 			return -EFAULT;
3799 		return 0;
3800 	}
3801 #endif
3802 	return put_timespec64(&ts, userstamp);
3803 }
3804 EXPORT_SYMBOL(sock_gettstamp);
3805 
3806 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3807 {
3808 	if (!sock_flag(sk, flag)) {
3809 		unsigned long previous_flags = sk->sk_flags;
3810 
3811 		sock_set_flag(sk, flag);
3812 		/*
3813 		 * we just set one of the two flags which require net
3814 		 * time stamping, but time stamping might have been on
3815 		 * already because of the other one
3816 		 */
3817 		if (sock_needs_netstamp(sk) &&
3818 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3819 			net_enable_timestamp();
3820 	}
3821 }
3822 
3823 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3824 		       int level, int type)
3825 {
3826 	struct sock_exterr_skb *serr;
3827 	struct sk_buff *skb;
3828 	int copied, err;
3829 
3830 	err = -EAGAIN;
3831 	skb = sock_dequeue_err_skb(sk);
3832 	if (skb == NULL)
3833 		goto out;
3834 
3835 	copied = skb->len;
3836 	if (copied > len) {
3837 		msg->msg_flags |= MSG_TRUNC;
3838 		copied = len;
3839 	}
3840 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3841 	if (err)
3842 		goto out_free_skb;
3843 
3844 	sock_recv_timestamp(msg, sk, skb);
3845 
3846 	serr = SKB_EXT_ERR(skb);
3847 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3848 
3849 	msg->msg_flags |= MSG_ERRQUEUE;
3850 	err = copied;
3851 
3852 out_free_skb:
3853 	kfree_skb(skb);
3854 out:
3855 	return err;
3856 }
3857 EXPORT_SYMBOL(sock_recv_errqueue);
3858 
3859 /*
3860  *	Get a socket option on an socket.
3861  *
3862  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3863  *	asynchronous errors should be reported by getsockopt. We assume
3864  *	this means if you specify SO_ERROR (otherwise what is the point of it).
3865  */
3866 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3867 			   char __user *optval, int __user *optlen)
3868 {
3869 	struct sock *sk = sock->sk;
3870 
3871 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3872 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3873 }
3874 EXPORT_SYMBOL(sock_common_getsockopt);
3875 
3876 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3877 			int flags)
3878 {
3879 	struct sock *sk = sock->sk;
3880 	int addr_len = 0;
3881 	int err;
3882 
3883 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3884 	if (err >= 0)
3885 		msg->msg_namelen = addr_len;
3886 	return err;
3887 }
3888 EXPORT_SYMBOL(sock_common_recvmsg);
3889 
3890 /*
3891  *	Set socket options on an inet socket.
3892  */
3893 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3894 			   sockptr_t optval, unsigned int optlen)
3895 {
3896 	struct sock *sk = sock->sk;
3897 
3898 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3899 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3900 }
3901 EXPORT_SYMBOL(sock_common_setsockopt);
3902 
3903 void sk_common_release(struct sock *sk)
3904 {
3905 	if (sk->sk_prot->destroy)
3906 		sk->sk_prot->destroy(sk);
3907 
3908 	/*
3909 	 * Observation: when sk_common_release is called, processes have
3910 	 * no access to socket. But net still has.
3911 	 * Step one, detach it from networking:
3912 	 *
3913 	 * A. Remove from hash tables.
3914 	 */
3915 
3916 	sk->sk_prot->unhash(sk);
3917 
3918 	/*
3919 	 * In this point socket cannot receive new packets, but it is possible
3920 	 * that some packets are in flight because some CPU runs receiver and
3921 	 * did hash table lookup before we unhashed socket. They will achieve
3922 	 * receive queue and will be purged by socket destructor.
3923 	 *
3924 	 * Also we still have packets pending on receive queue and probably,
3925 	 * our own packets waiting in device queues. sock_destroy will drain
3926 	 * receive queue, but transmitted packets will delay socket destruction
3927 	 * until the last reference will be released.
3928 	 */
3929 
3930 	sock_orphan(sk);
3931 
3932 	xfrm_sk_free_policy(sk);
3933 
3934 	sock_put(sk);
3935 }
3936 EXPORT_SYMBOL(sk_common_release);
3937 
3938 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3939 {
3940 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3941 
3942 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3943 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3944 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3945 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3946 	mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
3947 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3948 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3949 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3950 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3951 }
3952 
3953 #ifdef CONFIG_PROC_FS
3954 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3955 
3956 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3957 {
3958 	int cpu, idx = prot->inuse_idx;
3959 	int res = 0;
3960 
3961 	for_each_possible_cpu(cpu)
3962 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3963 
3964 	return res >= 0 ? res : 0;
3965 }
3966 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3967 
3968 int sock_inuse_get(struct net *net)
3969 {
3970 	int cpu, res = 0;
3971 
3972 	for_each_possible_cpu(cpu)
3973 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3974 
3975 	return res;
3976 }
3977 
3978 EXPORT_SYMBOL_GPL(sock_inuse_get);
3979 
3980 static int __net_init sock_inuse_init_net(struct net *net)
3981 {
3982 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3983 	if (net->core.prot_inuse == NULL)
3984 		return -ENOMEM;
3985 	return 0;
3986 }
3987 
3988 static void __net_exit sock_inuse_exit_net(struct net *net)
3989 {
3990 	free_percpu(net->core.prot_inuse);
3991 }
3992 
3993 static struct pernet_operations net_inuse_ops = {
3994 	.init = sock_inuse_init_net,
3995 	.exit = sock_inuse_exit_net,
3996 };
3997 
3998 static __init int net_inuse_init(void)
3999 {
4000 	if (register_pernet_subsys(&net_inuse_ops))
4001 		panic("Cannot initialize net inuse counters");
4002 
4003 	return 0;
4004 }
4005 
4006 core_initcall(net_inuse_init);
4007 
4008 static int assign_proto_idx(struct proto *prot)
4009 {
4010 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4011 
4012 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
4013 		pr_err("PROTO_INUSE_NR exhausted\n");
4014 		return -ENOSPC;
4015 	}
4016 
4017 	set_bit(prot->inuse_idx, proto_inuse_idx);
4018 	return 0;
4019 }
4020 
4021 static void release_proto_idx(struct proto *prot)
4022 {
4023 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
4024 		clear_bit(prot->inuse_idx, proto_inuse_idx);
4025 }
4026 #else
4027 static inline int assign_proto_idx(struct proto *prot)
4028 {
4029 	return 0;
4030 }
4031 
4032 static inline void release_proto_idx(struct proto *prot)
4033 {
4034 }
4035 
4036 #endif
4037 
4038 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4039 {
4040 	if (!twsk_prot)
4041 		return;
4042 	kfree(twsk_prot->twsk_slab_name);
4043 	twsk_prot->twsk_slab_name = NULL;
4044 	kmem_cache_destroy(twsk_prot->twsk_slab);
4045 	twsk_prot->twsk_slab = NULL;
4046 }
4047 
4048 static int tw_prot_init(const struct proto *prot)
4049 {
4050 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4051 
4052 	if (!twsk_prot)
4053 		return 0;
4054 
4055 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4056 					      prot->name);
4057 	if (!twsk_prot->twsk_slab_name)
4058 		return -ENOMEM;
4059 
4060 	twsk_prot->twsk_slab =
4061 		kmem_cache_create(twsk_prot->twsk_slab_name,
4062 				  twsk_prot->twsk_obj_size, 0,
4063 				  SLAB_ACCOUNT | prot->slab_flags,
4064 				  NULL);
4065 	if (!twsk_prot->twsk_slab) {
4066 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4067 			prot->name);
4068 		return -ENOMEM;
4069 	}
4070 
4071 	return 0;
4072 }
4073 
4074 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4075 {
4076 	if (!rsk_prot)
4077 		return;
4078 	kfree(rsk_prot->slab_name);
4079 	rsk_prot->slab_name = NULL;
4080 	kmem_cache_destroy(rsk_prot->slab);
4081 	rsk_prot->slab = NULL;
4082 }
4083 
4084 static int req_prot_init(const struct proto *prot)
4085 {
4086 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
4087 
4088 	if (!rsk_prot)
4089 		return 0;
4090 
4091 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4092 					prot->name);
4093 	if (!rsk_prot->slab_name)
4094 		return -ENOMEM;
4095 
4096 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4097 					   rsk_prot->obj_size, 0,
4098 					   SLAB_ACCOUNT | prot->slab_flags,
4099 					   NULL);
4100 
4101 	if (!rsk_prot->slab) {
4102 		pr_crit("%s: Can't create request sock SLAB cache!\n",
4103 			prot->name);
4104 		return -ENOMEM;
4105 	}
4106 	return 0;
4107 }
4108 
4109 int proto_register(struct proto *prot, int alloc_slab)
4110 {
4111 	int ret = -ENOBUFS;
4112 
4113 	if (prot->memory_allocated && !prot->sysctl_mem) {
4114 		pr_err("%s: missing sysctl_mem\n", prot->name);
4115 		return -EINVAL;
4116 	}
4117 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4118 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4119 		return -EINVAL;
4120 	}
4121 	if (alloc_slab) {
4122 		prot->slab = kmem_cache_create_usercopy(prot->name,
4123 					prot->obj_size, 0,
4124 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4125 					prot->slab_flags,
4126 					prot->useroffset, prot->usersize,
4127 					NULL);
4128 
4129 		if (prot->slab == NULL) {
4130 			pr_crit("%s: Can't create sock SLAB cache!\n",
4131 				prot->name);
4132 			goto out;
4133 		}
4134 
4135 		if (req_prot_init(prot))
4136 			goto out_free_request_sock_slab;
4137 
4138 		if (tw_prot_init(prot))
4139 			goto out_free_timewait_sock_slab;
4140 	}
4141 
4142 	mutex_lock(&proto_list_mutex);
4143 	ret = assign_proto_idx(prot);
4144 	if (ret) {
4145 		mutex_unlock(&proto_list_mutex);
4146 		goto out_free_timewait_sock_slab;
4147 	}
4148 	list_add(&prot->node, &proto_list);
4149 	mutex_unlock(&proto_list_mutex);
4150 	return ret;
4151 
4152 out_free_timewait_sock_slab:
4153 	if (alloc_slab)
4154 		tw_prot_cleanup(prot->twsk_prot);
4155 out_free_request_sock_slab:
4156 	if (alloc_slab) {
4157 		req_prot_cleanup(prot->rsk_prot);
4158 
4159 		kmem_cache_destroy(prot->slab);
4160 		prot->slab = NULL;
4161 	}
4162 out:
4163 	return ret;
4164 }
4165 EXPORT_SYMBOL(proto_register);
4166 
4167 void proto_unregister(struct proto *prot)
4168 {
4169 	mutex_lock(&proto_list_mutex);
4170 	release_proto_idx(prot);
4171 	list_del(&prot->node);
4172 	mutex_unlock(&proto_list_mutex);
4173 
4174 	kmem_cache_destroy(prot->slab);
4175 	prot->slab = NULL;
4176 
4177 	req_prot_cleanup(prot->rsk_prot);
4178 	tw_prot_cleanup(prot->twsk_prot);
4179 }
4180 EXPORT_SYMBOL(proto_unregister);
4181 
4182 int sock_load_diag_module(int family, int protocol)
4183 {
4184 	if (!protocol) {
4185 		if (!sock_is_registered(family))
4186 			return -ENOENT;
4187 
4188 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4189 				      NETLINK_SOCK_DIAG, family);
4190 	}
4191 
4192 #ifdef CONFIG_INET
4193 	if (family == AF_INET &&
4194 	    protocol != IPPROTO_RAW &&
4195 	    protocol < MAX_INET_PROTOS &&
4196 	    !rcu_access_pointer(inet_protos[protocol]))
4197 		return -ENOENT;
4198 #endif
4199 
4200 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4201 			      NETLINK_SOCK_DIAG, family, protocol);
4202 }
4203 EXPORT_SYMBOL(sock_load_diag_module);
4204 
4205 #ifdef CONFIG_PROC_FS
4206 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4207 	__acquires(proto_list_mutex)
4208 {
4209 	mutex_lock(&proto_list_mutex);
4210 	return seq_list_start_head(&proto_list, *pos);
4211 }
4212 
4213 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4214 {
4215 	return seq_list_next(v, &proto_list, pos);
4216 }
4217 
4218 static void proto_seq_stop(struct seq_file *seq, void *v)
4219 	__releases(proto_list_mutex)
4220 {
4221 	mutex_unlock(&proto_list_mutex);
4222 }
4223 
4224 static char proto_method_implemented(const void *method)
4225 {
4226 	return method == NULL ? 'n' : 'y';
4227 }
4228 static long sock_prot_memory_allocated(struct proto *proto)
4229 {
4230 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4231 }
4232 
4233 static const char *sock_prot_memory_pressure(struct proto *proto)
4234 {
4235 	return proto->memory_pressure != NULL ?
4236 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4237 }
4238 
4239 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4240 {
4241 
4242 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4243 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4244 		   proto->name,
4245 		   proto->obj_size,
4246 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4247 		   sock_prot_memory_allocated(proto),
4248 		   sock_prot_memory_pressure(proto),
4249 		   proto->max_header,
4250 		   proto->slab == NULL ? "no" : "yes",
4251 		   module_name(proto->owner),
4252 		   proto_method_implemented(proto->close),
4253 		   proto_method_implemented(proto->connect),
4254 		   proto_method_implemented(proto->disconnect),
4255 		   proto_method_implemented(proto->accept),
4256 		   proto_method_implemented(proto->ioctl),
4257 		   proto_method_implemented(proto->init),
4258 		   proto_method_implemented(proto->destroy),
4259 		   proto_method_implemented(proto->shutdown),
4260 		   proto_method_implemented(proto->setsockopt),
4261 		   proto_method_implemented(proto->getsockopt),
4262 		   proto_method_implemented(proto->sendmsg),
4263 		   proto_method_implemented(proto->recvmsg),
4264 		   proto_method_implemented(proto->bind),
4265 		   proto_method_implemented(proto->backlog_rcv),
4266 		   proto_method_implemented(proto->hash),
4267 		   proto_method_implemented(proto->unhash),
4268 		   proto_method_implemented(proto->get_port),
4269 		   proto_method_implemented(proto->enter_memory_pressure));
4270 }
4271 
4272 static int proto_seq_show(struct seq_file *seq, void *v)
4273 {
4274 	if (v == &proto_list)
4275 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4276 			   "protocol",
4277 			   "size",
4278 			   "sockets",
4279 			   "memory",
4280 			   "press",
4281 			   "maxhdr",
4282 			   "slab",
4283 			   "module",
4284 			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4285 	else
4286 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4287 	return 0;
4288 }
4289 
4290 static const struct seq_operations proto_seq_ops = {
4291 	.start  = proto_seq_start,
4292 	.next   = proto_seq_next,
4293 	.stop   = proto_seq_stop,
4294 	.show   = proto_seq_show,
4295 };
4296 
4297 static __net_init int proto_init_net(struct net *net)
4298 {
4299 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4300 			sizeof(struct seq_net_private)))
4301 		return -ENOMEM;
4302 
4303 	return 0;
4304 }
4305 
4306 static __net_exit void proto_exit_net(struct net *net)
4307 {
4308 	remove_proc_entry("protocols", net->proc_net);
4309 }
4310 
4311 
4312 static __net_initdata struct pernet_operations proto_net_ops = {
4313 	.init = proto_init_net,
4314 	.exit = proto_exit_net,
4315 };
4316 
4317 static int __init proto_init(void)
4318 {
4319 	return register_pernet_subsys(&proto_net_ops);
4320 }
4321 
4322 subsys_initcall(proto_init);
4323 
4324 #endif /* PROC_FS */
4325 
4326 #ifdef CONFIG_NET_RX_BUSY_POLL
4327 bool sk_busy_loop_end(void *p, unsigned long start_time)
4328 {
4329 	struct sock *sk = p;
4330 
4331 	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4332 		return true;
4333 
4334 	if (sk_is_udp(sk) &&
4335 	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4336 		return true;
4337 
4338 	return sk_busy_loop_timeout(sk, start_time);
4339 }
4340 EXPORT_SYMBOL(sk_busy_loop_end);
4341 #endif /* CONFIG_NET_RX_BUSY_POLL */
4342 
4343 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4344 {
4345 	if (!sk->sk_prot->bind_add)
4346 		return -EOPNOTSUPP;
4347 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4348 }
4349 EXPORT_SYMBOL(sock_bind_add);
4350 
4351 /* Copy 'size' bytes from userspace and return `size` back to userspace */
4352 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4353 		     void __user *arg, void *karg, size_t size)
4354 {
4355 	int ret;
4356 
4357 	if (copy_from_user(karg, arg, size))
4358 		return -EFAULT;
4359 
4360 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4361 	if (ret)
4362 		return ret;
4363 
4364 	if (copy_to_user(arg, karg, size))
4365 		return -EFAULT;
4366 
4367 	return 0;
4368 }
4369 EXPORT_SYMBOL(sock_ioctl_inout);
4370 
4371 /* This is the most common ioctl prep function, where the result (4 bytes) is
4372  * copied back to userspace if the ioctl() returns successfully. No input is
4373  * copied from userspace as input argument.
4374  */
4375 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4376 {
4377 	int ret, karg = 0;
4378 
4379 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4380 	if (ret)
4381 		return ret;
4382 
4383 	return put_user(karg, (int __user *)arg);
4384 }
4385 
4386 /* A wrapper around sock ioctls, which copies the data from userspace
4387  * (depending on the protocol/ioctl), and copies back the result to userspace.
4388  * The main motivation for this function is to pass kernel memory to the
4389  * protocol ioctl callbacks, instead of userspace memory.
4390  */
4391 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4392 {
4393 	int rc = 1;
4394 
4395 	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4396 		rc = ipmr_sk_ioctl(sk, cmd, arg);
4397 	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4398 		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4399 	else if (sk_is_phonet(sk))
4400 		rc = phonet_sk_ioctl(sk, cmd, arg);
4401 
4402 	/* If ioctl was processed, returns its value */
4403 	if (rc <= 0)
4404 		return rc;
4405 
4406 	/* Otherwise call the default handler */
4407 	return sock_ioctl_out(sk, cmd, arg);
4408 }
4409 EXPORT_SYMBOL(sk_ioctl);
4410 
4411 static int __init sock_struct_check(void)
4412 {
4413 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4414 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4415 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4416 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4417 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4418 
4419 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4420 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4421 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4422 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4423 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4424 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4425 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4426 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4427 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4428 
4429 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4430 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4431 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4432 
4433 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4434 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4435 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4436 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4437 
4438 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4439 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4440 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_sndbuf);
4441 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4442 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4443 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4444 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4445 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4446 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4447 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm);
4448 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status);
4449 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4450 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4451 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4452 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4453 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4454 
4455 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4456 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4457 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4458 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4459 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4460 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4461 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4462 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4463 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4464 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4465 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4466 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4467 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4468 	return 0;
4469 }
4470 
4471 core_initcall(sock_struct_check);
4472