xref: /linux/net/core/sock.c (revision 5d39580f68e6ddeedd15e587282207489dfb3da2)
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, int wmem_alloc);
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 = 4 << 20;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = 4 << 20;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_DEFAULT;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_DEFAULT;
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 		sk_drops_inc(sk);
495 		trace_sock_rcvqueue_full(sk, skb);
496 		return -ENOMEM;
497 	}
498 
499 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 		sk_drops_inc(sk);
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 enum skb_drop_reason
524 sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb)
525 {
526 	enum skb_drop_reason drop_reason;
527 	int err;
528 
529 	drop_reason = sk_filter_reason(sk, skb);
530 	if (drop_reason)
531 		return drop_reason;
532 
533 	err = __sock_queue_rcv_skb(sk, skb);
534 	switch (err) {
535 	case -ENOMEM:
536 		return SKB_DROP_REASON_SOCKET_RCVBUFF;
537 	case -ENOBUFS:
538 		return SKB_DROP_REASON_PROTO_MEM;
539 	}
540 	return SKB_NOT_DROPPED_YET;
541 }
542 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
543 
544 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
545 		     const int nested, unsigned int trim_cap, bool refcounted)
546 {
547 	enum skb_drop_reason reason;
548 	int rc = NET_RX_SUCCESS;
549 	int err;
550 
551 	reason = sk_filter_trim_cap(sk, skb, trim_cap);
552 	if (reason)
553 		goto discard_and_relse;
554 
555 	skb->dev = NULL;
556 
557 	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
558 		sk_drops_inc(sk);
559 		reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
560 		goto discard_and_relse;
561 	}
562 	if (nested)
563 		bh_lock_sock_nested(sk);
564 	else
565 		bh_lock_sock(sk);
566 	if (!sock_owned_by_user(sk)) {
567 		/*
568 		 * trylock + unlock semantics:
569 		 */
570 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
571 
572 		rc = sk_backlog_rcv(sk, skb);
573 
574 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
575 	} else if ((err = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))) {
576 		bh_unlock_sock(sk);
577 		if (err == -ENOMEM)
578 			reason = SKB_DROP_REASON_PFMEMALLOC;
579 		if (err == -ENOBUFS)
580 			reason = SKB_DROP_REASON_SOCKET_BACKLOG;
581 		sk_drops_inc(sk);
582 		goto discard_and_relse;
583 	}
584 
585 	bh_unlock_sock(sk);
586 out:
587 	if (refcounted)
588 		sock_put(sk);
589 	return rc;
590 discard_and_relse:
591 	sk_skb_reason_drop(sk, skb, reason);
592 	goto out;
593 }
594 EXPORT_SYMBOL(__sk_receive_skb);
595 
596 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
597 							  u32));
598 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
599 							   u32));
600 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
601 {
602 	struct dst_entry *dst = __sk_dst_get(sk);
603 
604 	if (dst && READ_ONCE(dst->obsolete) &&
605 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
606 			       dst, cookie) == NULL) {
607 		sk_tx_queue_clear(sk);
608 		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
609 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
610 		dst_release(dst);
611 		return NULL;
612 	}
613 
614 	return dst;
615 }
616 EXPORT_SYMBOL(__sk_dst_check);
617 
618 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
619 {
620 	struct dst_entry *dst = sk_dst_get(sk);
621 
622 	if (dst && READ_ONCE(dst->obsolete) &&
623 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
624 			       dst, cookie) == NULL) {
625 		sk_dst_reset(sk);
626 		dst_release(dst);
627 		return NULL;
628 	}
629 
630 	return dst;
631 }
632 EXPORT_SYMBOL(sk_dst_check);
633 
634 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
635 {
636 	int ret = -ENOPROTOOPT;
637 #ifdef CONFIG_NETDEVICES
638 	struct net *net = sock_net(sk);
639 
640 	/* Sorry... */
641 	ret = -EPERM;
642 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
643 		goto out;
644 
645 	ret = -EINVAL;
646 	if (ifindex < 0)
647 		goto out;
648 
649 	/* Paired with all READ_ONCE() done locklessly. */
650 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
651 
652 	if (sk->sk_prot->rehash)
653 		sk->sk_prot->rehash(sk);
654 	sk_dst_reset(sk);
655 
656 	ret = 0;
657 
658 out:
659 #endif
660 
661 	return ret;
662 }
663 
664 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
665 {
666 	int ret;
667 
668 	if (lock_sk)
669 		lock_sock(sk);
670 	ret = sock_bindtoindex_locked(sk, ifindex);
671 	if (lock_sk)
672 		release_sock(sk);
673 
674 	return ret;
675 }
676 EXPORT_SYMBOL(sock_bindtoindex);
677 
678 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
679 {
680 	int ret = -ENOPROTOOPT;
681 #ifdef CONFIG_NETDEVICES
682 	struct net *net = sock_net(sk);
683 	char devname[IFNAMSIZ];
684 	int index;
685 
686 	ret = -EINVAL;
687 	if (optlen < 0)
688 		goto out;
689 
690 	/* Bind this socket to a particular device like "eth0",
691 	 * as specified in the passed interface name. If the
692 	 * name is "" or the option length is zero the socket
693 	 * is not bound.
694 	 */
695 	if (optlen > IFNAMSIZ - 1)
696 		optlen = IFNAMSIZ - 1;
697 	memset(devname, 0, sizeof(devname));
698 
699 	ret = -EFAULT;
700 	if (copy_from_sockptr(devname, optval, optlen))
701 		goto out;
702 
703 	index = 0;
704 	if (devname[0] != '\0') {
705 		struct net_device *dev;
706 
707 		rcu_read_lock();
708 		dev = dev_get_by_name_rcu(net, devname);
709 		if (dev)
710 			index = dev->ifindex;
711 		rcu_read_unlock();
712 		ret = -ENODEV;
713 		if (!dev)
714 			goto out;
715 	}
716 
717 	sockopt_lock_sock(sk);
718 	ret = sock_bindtoindex_locked(sk, index);
719 	sockopt_release_sock(sk);
720 out:
721 #endif
722 
723 	return ret;
724 }
725 
726 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
727 				sockptr_t optlen, int len)
728 {
729 	int ret = -ENOPROTOOPT;
730 #ifdef CONFIG_NETDEVICES
731 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
732 	struct net *net = sock_net(sk);
733 	char devname[IFNAMSIZ];
734 
735 	if (bound_dev_if == 0) {
736 		len = 0;
737 		goto zero;
738 	}
739 
740 	ret = -EINVAL;
741 	if (len < IFNAMSIZ)
742 		goto out;
743 
744 	ret = netdev_get_name(net, devname, bound_dev_if);
745 	if (ret)
746 		goto out;
747 
748 	len = strlen(devname) + 1;
749 
750 	ret = -EFAULT;
751 	if (copy_to_sockptr(optval, devname, len))
752 		goto out;
753 
754 zero:
755 	ret = -EFAULT;
756 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
757 		goto out;
758 
759 	ret = 0;
760 
761 out:
762 #endif
763 
764 	return ret;
765 }
766 
767 bool sk_mc_loop(const struct sock *sk)
768 {
769 	if (dev_recursion_level())
770 		return false;
771 	if (!sk)
772 		return true;
773 	/* IPV6_ADDRFORM can change sk->sk_family under us. */
774 	switch (READ_ONCE(sk->sk_family)) {
775 	case AF_INET:
776 		return inet_test_bit(MC_LOOP, sk);
777 #if IS_ENABLED(CONFIG_IPV6)
778 	case AF_INET6:
779 		return inet6_test_bit(MC6_LOOP, sk);
780 #endif
781 	}
782 	WARN_ON_ONCE(1);
783 	return true;
784 }
785 EXPORT_SYMBOL(sk_mc_loop);
786 
787 void sock_set_reuseaddr(struct sock *sk)
788 {
789 	lock_sock(sk);
790 	sk->sk_reuse = SK_CAN_REUSE;
791 	release_sock(sk);
792 }
793 EXPORT_SYMBOL(sock_set_reuseaddr);
794 
795 void sock_set_reuseport(struct sock *sk)
796 {
797 	lock_sock(sk);
798 	sk->sk_reuseport = true;
799 	release_sock(sk);
800 }
801 EXPORT_SYMBOL(sock_set_reuseport);
802 
803 void sock_no_linger(struct sock *sk)
804 {
805 	lock_sock(sk);
806 	WRITE_ONCE(sk->sk_lingertime, 0);
807 	sock_set_flag(sk, SOCK_LINGER);
808 	release_sock(sk);
809 }
810 EXPORT_SYMBOL(sock_no_linger);
811 
812 void sock_set_priority(struct sock *sk, u32 priority)
813 {
814 	WRITE_ONCE(sk->sk_priority, priority);
815 }
816 EXPORT_SYMBOL(sock_set_priority);
817 
818 void sock_set_sndtimeo(struct sock *sk, s64 secs)
819 {
820 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
821 		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
822 	else
823 		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
824 }
825 EXPORT_SYMBOL(sock_set_sndtimeo);
826 
827 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
828 {
829 	sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
830 	sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
831 	if (val)  {
832 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
833 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
834 	}
835 }
836 
837 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
838 {
839 	switch (optname) {
840 	case SO_TIMESTAMP_OLD:
841 		__sock_set_timestamps(sk, valbool, false, false);
842 		break;
843 	case SO_TIMESTAMP_NEW:
844 		__sock_set_timestamps(sk, valbool, true, false);
845 		break;
846 	case SO_TIMESTAMPNS_OLD:
847 		__sock_set_timestamps(sk, valbool, false, true);
848 		break;
849 	case SO_TIMESTAMPNS_NEW:
850 		__sock_set_timestamps(sk, valbool, true, true);
851 		break;
852 	}
853 }
854 
855 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
856 {
857 	struct net *net = sock_net(sk);
858 	struct net_device *dev = NULL;
859 	bool match = false;
860 	int *vclock_index;
861 	int i, num;
862 
863 	if (sk->sk_bound_dev_if)
864 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
865 
866 	if (!dev) {
867 		pr_err("%s: sock not bind to device\n", __func__);
868 		return -EOPNOTSUPP;
869 	}
870 
871 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
872 	dev_put(dev);
873 
874 	for (i = 0; i < num; i++) {
875 		if (*(vclock_index + i) == phc_index) {
876 			match = true;
877 			break;
878 		}
879 	}
880 
881 	if (num > 0)
882 		kfree(vclock_index);
883 
884 	if (!match)
885 		return -EINVAL;
886 
887 	WRITE_ONCE(sk->sk_bind_phc, phc_index);
888 
889 	return 0;
890 }
891 
892 int sock_set_timestamping(struct sock *sk, int optname,
893 			  struct so_timestamping timestamping)
894 {
895 	int val = timestamping.flags;
896 	int ret;
897 
898 	if (val & ~SOF_TIMESTAMPING_MASK)
899 		return -EINVAL;
900 
901 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
902 	    !(val & SOF_TIMESTAMPING_OPT_ID))
903 		return -EINVAL;
904 
905 	if (val & SOF_TIMESTAMPING_OPT_ID &&
906 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
907 		if (sk_is_tcp(sk)) {
908 			if ((1 << sk->sk_state) &
909 			    (TCPF_CLOSE | TCPF_LISTEN))
910 				return -EINVAL;
911 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
912 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
913 			else
914 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
915 		} else {
916 			atomic_set(&sk->sk_tskey, 0);
917 		}
918 	}
919 
920 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
921 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
922 		return -EINVAL;
923 
924 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
925 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
926 		if (ret)
927 			return ret;
928 	}
929 
930 	WRITE_ONCE(sk->sk_tsflags, val);
931 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
932 	sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
933 
934 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
935 		sock_enable_timestamp(sk,
936 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
937 	else
938 		sock_disable_timestamp(sk,
939 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
940 	return 0;
941 }
942 
943 #if defined(CONFIG_CGROUP_BPF)
944 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
945 {
946 	struct bpf_sock_ops_kern sock_ops;
947 
948 	memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
949 	sock_ops.op = op;
950 	sock_ops.is_fullsock = 1;
951 	sock_ops.sk = sk;
952 	bpf_skops_init_skb(&sock_ops, skb, 0);
953 	__cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
954 }
955 #endif
956 
957 void sock_set_keepalive(struct sock *sk)
958 {
959 	lock_sock(sk);
960 	if (sk->sk_prot->keepalive)
961 		sk->sk_prot->keepalive(sk, true);
962 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
963 	release_sock(sk);
964 }
965 EXPORT_SYMBOL(sock_set_keepalive);
966 
967 static void __sock_set_rcvbuf(struct sock *sk, int val)
968 {
969 	struct socket *sock = sk->sk_socket;
970 
971 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
972 	 * as a negative value.
973 	 */
974 	val = min_t(int, val, INT_MAX / 2);
975 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
976 
977 	/* We double it on the way in to account for "struct sk_buff" etc.
978 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
979 	 * will allow that much actual data to be received on that socket.
980 	 *
981 	 * Applications are unaware that "struct sk_buff" and other overheads
982 	 * allocate from the receive buffer during socket buffer allocation.
983 	 *
984 	 * And after considering the possible alternatives, returning the value
985 	 * we actually used in getsockopt is the most desirable behavior.
986 	 */
987 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
988 
989 	if (sock) {
990 		const struct proto_ops *ops = READ_ONCE(sock->ops);
991 
992 		if (ops->set_rcvbuf)
993 			ops->set_rcvbuf(sk, sk->sk_rcvbuf);
994 	}
995 }
996 
997 void sock_set_rcvbuf(struct sock *sk, int val)
998 {
999 	lock_sock(sk);
1000 	__sock_set_rcvbuf(sk, val);
1001 	release_sock(sk);
1002 }
1003 EXPORT_SYMBOL(sock_set_rcvbuf);
1004 
1005 static void __sock_set_mark(struct sock *sk, u32 val)
1006 {
1007 	if (val != sk->sk_mark) {
1008 		WRITE_ONCE(sk->sk_mark, val);
1009 		sk_dst_reset(sk);
1010 	}
1011 }
1012 
1013 void sock_set_mark(struct sock *sk, u32 val)
1014 {
1015 	lock_sock(sk);
1016 	__sock_set_mark(sk, val);
1017 	release_sock(sk);
1018 }
1019 EXPORT_SYMBOL(sock_set_mark);
1020 
1021 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1022 {
1023 	/* Round down bytes to multiple of pages */
1024 	bytes = round_down(bytes, PAGE_SIZE);
1025 
1026 	WARN_ON(bytes > sk->sk_reserved_mem);
1027 	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1028 	sk_mem_reclaim(sk);
1029 }
1030 
1031 static int sock_reserve_memory(struct sock *sk, int bytes)
1032 {
1033 	long allocated;
1034 	bool charged;
1035 	int pages;
1036 
1037 	if (!mem_cgroup_sk_enabled(sk) || !sk_has_account(sk))
1038 		return -EOPNOTSUPP;
1039 
1040 	if (!bytes)
1041 		return 0;
1042 
1043 	pages = sk_mem_pages(bytes);
1044 
1045 	/* pre-charge to memcg */
1046 	charged = mem_cgroup_sk_charge(sk, pages,
1047 				       GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1048 	if (!charged)
1049 		return -ENOMEM;
1050 
1051 	if (sk->sk_bypass_prot_mem)
1052 		goto success;
1053 
1054 	/* pre-charge to forward_alloc */
1055 	sk_memory_allocated_add(sk, pages);
1056 	allocated = sk_memory_allocated(sk);
1057 
1058 	/* If the system goes into memory pressure with this
1059 	 * precharge, give up and return error.
1060 	 */
1061 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1062 		sk_memory_allocated_sub(sk, pages);
1063 		mem_cgroup_sk_uncharge(sk, pages);
1064 		return -ENOMEM;
1065 	}
1066 
1067 success:
1068 	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1069 
1070 	WRITE_ONCE(sk->sk_reserved_mem,
1071 		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1072 
1073 	return 0;
1074 }
1075 
1076 #ifdef CONFIG_PAGE_POOL
1077 
1078 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1079  * in 1 syscall. The limit exists to limit the amount of memory the kernel
1080  * allocates to copy these tokens, and to prevent looping over the frags for
1081  * too long.
1082  */
1083 #define MAX_DONTNEED_TOKENS 128
1084 #define MAX_DONTNEED_FRAGS 1024
1085 
1086 static noinline_for_stack int
1087 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1088 {
1089 	unsigned int num_tokens, i, j, k, netmem_num = 0;
1090 	struct dmabuf_token *tokens;
1091 	int ret = 0, num_frags = 0;
1092 	netmem_ref netmems[16];
1093 
1094 	if (!sk_is_tcp(sk))
1095 		return -EBADF;
1096 
1097 	if (optlen % sizeof(*tokens) ||
1098 	    optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1099 		return -EINVAL;
1100 
1101 	num_tokens = optlen / sizeof(*tokens);
1102 	tokens = kvmalloc_objs(*tokens, num_tokens);
1103 	if (!tokens)
1104 		return -ENOMEM;
1105 
1106 	if (copy_from_sockptr(tokens, optval, optlen)) {
1107 		kvfree(tokens);
1108 		return -EFAULT;
1109 	}
1110 
1111 	xa_lock_bh(&sk->sk_user_frags);
1112 	for (i = 0; i < num_tokens; i++) {
1113 		for (j = 0; j < tokens[i].token_count; j++) {
1114 			if (++num_frags > MAX_DONTNEED_FRAGS)
1115 				goto frag_limit_reached;
1116 
1117 			netmem_ref netmem = (__force netmem_ref)__xa_erase(
1118 				&sk->sk_user_frags, tokens[i].token_start + j);
1119 
1120 			if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1121 				continue;
1122 
1123 			netmems[netmem_num++] = netmem;
1124 			if (netmem_num == ARRAY_SIZE(netmems)) {
1125 				xa_unlock_bh(&sk->sk_user_frags);
1126 				for (k = 0; k < netmem_num; k++)
1127 					WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1128 				netmem_num = 0;
1129 				xa_lock_bh(&sk->sk_user_frags);
1130 			}
1131 			ret++;
1132 		}
1133 	}
1134 
1135 frag_limit_reached:
1136 	xa_unlock_bh(&sk->sk_user_frags);
1137 	for (k = 0; k < netmem_num; k++)
1138 		WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1139 
1140 	kvfree(tokens);
1141 	return ret;
1142 }
1143 #endif
1144 
1145 void sockopt_lock_sock(struct sock *sk)
1146 {
1147 	/* When current->bpf_ctx is set, the setsockopt is called from
1148 	 * a bpf prog.  bpf has ensured the sk lock has been
1149 	 * acquired before calling setsockopt().
1150 	 */
1151 	if (has_current_bpf_ctx())
1152 		return;
1153 
1154 	lock_sock(sk);
1155 }
1156 EXPORT_SYMBOL(sockopt_lock_sock);
1157 
1158 void sockopt_release_sock(struct sock *sk)
1159 {
1160 	if (has_current_bpf_ctx())
1161 		return;
1162 
1163 	release_sock(sk);
1164 }
1165 EXPORT_SYMBOL(sockopt_release_sock);
1166 
1167 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1168 {
1169 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1170 }
1171 EXPORT_SYMBOL(sockopt_ns_capable);
1172 
1173 bool sockopt_capable(int cap)
1174 {
1175 	return has_current_bpf_ctx() || capable(cap);
1176 }
1177 EXPORT_SYMBOL(sockopt_capable);
1178 
1179 static int sockopt_validate_clockid(__kernel_clockid_t value)
1180 {
1181 	switch (value) {
1182 	case CLOCK_REALTIME:
1183 	case CLOCK_MONOTONIC:
1184 	case CLOCK_TAI:
1185 		return 0;
1186 	}
1187 	return -EINVAL;
1188 }
1189 
1190 /*
1191  *	This is meant for all protocols to use and covers goings on
1192  *	at the socket level. Everything here is generic.
1193  */
1194 
1195 int sk_setsockopt(struct sock *sk, int level, int optname,
1196 		  sockptr_t optval, unsigned int optlen)
1197 {
1198 	struct so_timestamping timestamping;
1199 	struct socket *sock = sk->sk_socket;
1200 	struct sock_txtime sk_txtime;
1201 	int val;
1202 	int valbool;
1203 	struct linger ling;
1204 	int ret = 0;
1205 
1206 	/*
1207 	 *	Options without arguments
1208 	 */
1209 
1210 	if (optname == SO_BINDTODEVICE)
1211 		return sock_setbindtodevice(sk, optval, optlen);
1212 
1213 	if (optlen < sizeof(int))
1214 		return -EINVAL;
1215 
1216 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1217 		return -EFAULT;
1218 
1219 	valbool = val ? 1 : 0;
1220 
1221 	/* handle options which do not require locking the socket. */
1222 	switch (optname) {
1223 	case SO_PRIORITY:
1224 		if (sk_set_prio_allowed(sk, val)) {
1225 			sock_set_priority(sk, val);
1226 			return 0;
1227 		}
1228 		return -EPERM;
1229 	case SO_TYPE:
1230 	case SO_PROTOCOL:
1231 	case SO_DOMAIN:
1232 	case SO_ERROR:
1233 		return -ENOPROTOOPT;
1234 #ifdef CONFIG_NET_RX_BUSY_POLL
1235 	case SO_BUSY_POLL:
1236 		if (val < 0)
1237 			return -EINVAL;
1238 		WRITE_ONCE(sk->sk_ll_usec, val);
1239 		return 0;
1240 	case SO_PREFER_BUSY_POLL:
1241 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1242 			return -EPERM;
1243 		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1244 		return 0;
1245 	case SO_BUSY_POLL_BUDGET:
1246 		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1247 		    !sockopt_capable(CAP_NET_ADMIN))
1248 			return -EPERM;
1249 		if (val < 0 || val > U16_MAX)
1250 			return -EINVAL;
1251 		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1252 		return 0;
1253 #endif
1254 	case SO_MAX_PACING_RATE:
1255 		{
1256 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1257 		unsigned long pacing_rate;
1258 
1259 		if (sizeof(ulval) != sizeof(val) &&
1260 		    optlen >= sizeof(ulval) &&
1261 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1262 			return -EFAULT;
1263 		}
1264 		if (ulval != ~0UL)
1265 			cmpxchg(&sk->sk_pacing_status,
1266 				SK_PACING_NONE,
1267 				SK_PACING_NEEDED);
1268 		/* Pairs with READ_ONCE() from sk_getsockopt() */
1269 		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1270 		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1271 		if (ulval < pacing_rate)
1272 			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1273 		return 0;
1274 		}
1275 	case SO_TXREHASH:
1276 		if (!sk_is_tcp(sk))
1277 			return -EOPNOTSUPP;
1278 		if (val < -1 || val > 1)
1279 			return -EINVAL;
1280 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1281 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1282 		/* Paired with READ_ONCE() in tcp_rtx_synack()
1283 		 * and sk_getsockopt().
1284 		 */
1285 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1286 		return 0;
1287 	case SO_PEEK_OFF:
1288 		{
1289 		int (*set_peek_off)(struct sock *sk, int val);
1290 
1291 		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1292 		if (set_peek_off)
1293 			ret = set_peek_off(sk, val);
1294 		else
1295 			ret = -EOPNOTSUPP;
1296 		return ret;
1297 		}
1298 #ifdef CONFIG_PAGE_POOL
1299 	case SO_DEVMEM_DONTNEED:
1300 		return sock_devmem_dontneed(sk, optval, optlen);
1301 #endif
1302 	case SO_SNDTIMEO_OLD:
1303 	case SO_SNDTIMEO_NEW:
1304 		return sock_set_timeout(&sk->sk_sndtimeo, optval,
1305 					optlen, optname == SO_SNDTIMEO_OLD);
1306 	case SO_RCVTIMEO_OLD:
1307 	case SO_RCVTIMEO_NEW:
1308 		return sock_set_timeout(&sk->sk_rcvtimeo, optval,
1309 					optlen, optname == SO_RCVTIMEO_OLD);
1310 	}
1311 
1312 	sockopt_lock_sock(sk);
1313 
1314 	switch (optname) {
1315 	case SO_DEBUG:
1316 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1317 			ret = -EACCES;
1318 		else
1319 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1320 		break;
1321 	case SO_REUSEADDR:
1322 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1323 		break;
1324 	case SO_REUSEPORT:
1325 		if (valbool && !sk_is_inet(sk))
1326 			ret = -EOPNOTSUPP;
1327 		else
1328 			sk->sk_reuseport = valbool;
1329 		break;
1330 	case SO_DONTROUTE:
1331 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1332 		sk_dst_reset(sk);
1333 		break;
1334 	case SO_BROADCAST:
1335 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1336 		break;
1337 	case SO_SNDBUF:
1338 		/* Don't error on this BSD doesn't and if you think
1339 		 * about it this is right. Otherwise apps have to
1340 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1341 		 * are treated in BSD as hints
1342 		 */
1343 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1344 set_sndbuf:
1345 		/* Ensure val * 2 fits into an int, to prevent max_t()
1346 		 * from treating it as a negative value.
1347 		 */
1348 		val = min_t(int, val, INT_MAX / 2);
1349 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1350 		WRITE_ONCE(sk->sk_sndbuf,
1351 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1352 		/* Wake up sending tasks if we upped the value. */
1353 		sk->sk_write_space(sk);
1354 		break;
1355 
1356 	case SO_SNDBUFFORCE:
1357 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1358 			ret = -EPERM;
1359 			break;
1360 		}
1361 
1362 		/* No negative values (to prevent underflow, as val will be
1363 		 * multiplied by 2).
1364 		 */
1365 		if (val < 0)
1366 			val = 0;
1367 		goto set_sndbuf;
1368 
1369 	case SO_RCVBUF:
1370 		/* Don't error on this BSD doesn't and if you think
1371 		 * about it this is right. Otherwise apps have to
1372 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1373 		 * are treated in BSD as hints
1374 		 */
1375 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1376 		break;
1377 
1378 	case SO_RCVBUFFORCE:
1379 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1380 			ret = -EPERM;
1381 			break;
1382 		}
1383 
1384 		/* No negative values (to prevent underflow, as val will be
1385 		 * multiplied by 2).
1386 		 */
1387 		__sock_set_rcvbuf(sk, max(val, 0));
1388 		break;
1389 
1390 	case SO_KEEPALIVE:
1391 		if (sk->sk_prot->keepalive)
1392 			sk->sk_prot->keepalive(sk, valbool);
1393 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1394 		break;
1395 
1396 	case SO_OOBINLINE:
1397 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1398 		break;
1399 
1400 	case SO_NO_CHECK:
1401 		sk->sk_no_check_tx = valbool;
1402 		break;
1403 
1404 	case SO_LINGER:
1405 		if (optlen < sizeof(ling)) {
1406 			ret = -EINVAL;	/* 1003.1g */
1407 			break;
1408 		}
1409 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1410 			ret = -EFAULT;
1411 			break;
1412 		}
1413 		if (!ling.l_onoff) {
1414 			sock_reset_flag(sk, SOCK_LINGER);
1415 		} else {
1416 			unsigned long t_sec = ling.l_linger;
1417 
1418 			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1419 				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1420 			else
1421 				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1422 			sock_set_flag(sk, SOCK_LINGER);
1423 		}
1424 		break;
1425 
1426 	case SO_BSDCOMPAT:
1427 		break;
1428 
1429 	case SO_TIMESTAMP_OLD:
1430 	case SO_TIMESTAMP_NEW:
1431 	case SO_TIMESTAMPNS_OLD:
1432 	case SO_TIMESTAMPNS_NEW:
1433 		sock_set_timestamp(sk, optname, valbool);
1434 		break;
1435 
1436 	case SO_TIMESTAMPING_NEW:
1437 	case SO_TIMESTAMPING_OLD:
1438 		if (optlen == sizeof(timestamping)) {
1439 			if (copy_from_sockptr(&timestamping, optval,
1440 					      sizeof(timestamping))) {
1441 				ret = -EFAULT;
1442 				break;
1443 			}
1444 		} else {
1445 			memset(&timestamping, 0, sizeof(timestamping));
1446 			timestamping.flags = val;
1447 		}
1448 		ret = sock_set_timestamping(sk, optname, timestamping);
1449 		break;
1450 
1451 	case SO_RCVLOWAT:
1452 		{
1453 		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1454 
1455 		if (val < 0)
1456 			val = INT_MAX;
1457 		if (sock)
1458 			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1459 		if (set_rcvlowat)
1460 			ret = set_rcvlowat(sk, val);
1461 		else
1462 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1463 		break;
1464 		}
1465 	case SO_ATTACH_FILTER: {
1466 		struct sock_fprog fprog;
1467 
1468 		if (sk_is_tcp(sk) &&
1469 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1470 			ret = -EPERM;
1471 			break;
1472 		}
1473 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1474 		if (!ret)
1475 			ret = sk_attach_filter(&fprog, sk);
1476 		break;
1477 	}
1478 	case SO_ATTACH_BPF:
1479 		ret = -EINVAL;
1480 		if (optlen == sizeof(u32)) {
1481 			u32 ufd;
1482 
1483 			ret = -EFAULT;
1484 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1485 				break;
1486 
1487 			ret = sk_attach_bpf(ufd, sk);
1488 		}
1489 		break;
1490 
1491 	case SO_ATTACH_REUSEPORT_CBPF: {
1492 		struct sock_fprog fprog;
1493 
1494 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1495 		if (!ret)
1496 			ret = sk_reuseport_attach_filter(&fprog, sk);
1497 		break;
1498 	}
1499 	case SO_ATTACH_REUSEPORT_EBPF:
1500 		ret = -EINVAL;
1501 		if (optlen == sizeof(u32)) {
1502 			u32 ufd;
1503 
1504 			ret = -EFAULT;
1505 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1506 				break;
1507 
1508 			ret = sk_reuseport_attach_bpf(ufd, sk);
1509 		}
1510 		break;
1511 
1512 	case SO_DETACH_REUSEPORT_BPF:
1513 		ret = reuseport_detach_prog(sk);
1514 		break;
1515 
1516 	case SO_DETACH_FILTER:
1517 		ret = sk_detach_filter(sk);
1518 		break;
1519 
1520 	case SO_LOCK_FILTER:
1521 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1522 			ret = -EPERM;
1523 		else
1524 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1525 		break;
1526 
1527 	case SO_MARK:
1528 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1529 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1530 			ret = -EPERM;
1531 			break;
1532 		}
1533 
1534 		__sock_set_mark(sk, val);
1535 		break;
1536 	case SO_RCVMARK:
1537 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1538 		break;
1539 
1540 	case SO_RCVPRIORITY:
1541 		sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1542 		break;
1543 
1544 	case SO_RXQ_OVFL:
1545 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1546 		break;
1547 
1548 	case SO_WIFI_STATUS:
1549 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1550 		break;
1551 
1552 	case SO_NOFCS:
1553 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1554 		break;
1555 
1556 	case SO_SELECT_ERR_QUEUE:
1557 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1558 		break;
1559 
1560 	case SO_PASSCRED:
1561 		if (sk_may_scm_recv(sk))
1562 			sk->sk_scm_credentials = valbool;
1563 		else
1564 			ret = -EOPNOTSUPP;
1565 		break;
1566 
1567 	case SO_PASSSEC:
1568 		if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk))
1569 			sk->sk_scm_security = valbool;
1570 		else
1571 			ret = -EOPNOTSUPP;
1572 		break;
1573 
1574 	case SO_PASSPIDFD:
1575 		if (sk_is_unix(sk))
1576 			sk->sk_scm_pidfd = valbool;
1577 		else
1578 			ret = -EOPNOTSUPP;
1579 		break;
1580 
1581 	case SO_PASSRIGHTS:
1582 		if (sk_is_unix(sk))
1583 			sk->sk_scm_rights = valbool;
1584 		else
1585 			ret = -EOPNOTSUPP;
1586 		break;
1587 
1588 	case SO_INCOMING_CPU:
1589 		reuseport_update_incoming_cpu(sk, val);
1590 		break;
1591 
1592 	case SO_CNX_ADVICE:
1593 		if (val == 1)
1594 			dst_negative_advice(sk);
1595 		break;
1596 
1597 	case SO_ZEROCOPY:
1598 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1599 			if (!(sk_is_tcp(sk) ||
1600 			      (sk->sk_type == SOCK_DGRAM &&
1601 			       sk->sk_protocol == IPPROTO_UDP)))
1602 				ret = -EOPNOTSUPP;
1603 		} else if (sk->sk_family != PF_RDS) {
1604 			ret = -EOPNOTSUPP;
1605 		}
1606 		if (!ret) {
1607 			if (val < 0 || val > 1)
1608 				ret = -EINVAL;
1609 			else
1610 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1611 		}
1612 		break;
1613 
1614 	case SO_TXTIME:
1615 		if (optlen != sizeof(struct sock_txtime)) {
1616 			ret = -EINVAL;
1617 			break;
1618 		} else if (copy_from_sockptr(&sk_txtime, optval,
1619 			   sizeof(struct sock_txtime))) {
1620 			ret = -EFAULT;
1621 			break;
1622 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1623 			ret = -EINVAL;
1624 			break;
1625 		}
1626 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1627 		 * scheduler has enough safe guards.
1628 		 */
1629 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1630 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1631 			ret = -EPERM;
1632 			break;
1633 		}
1634 
1635 		ret = sockopt_validate_clockid(sk_txtime.clockid);
1636 		if (ret)
1637 			break;
1638 
1639 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1640 		sk->sk_clockid = sk_txtime.clockid;
1641 		sk->sk_txtime_deadline_mode =
1642 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1643 		sk->sk_txtime_report_errors =
1644 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1645 		break;
1646 
1647 	case SO_BINDTOIFINDEX:
1648 		ret = sock_bindtoindex_locked(sk, val);
1649 		break;
1650 
1651 	case SO_BUF_LOCK:
1652 		if (val & ~SOCK_BUF_LOCK_MASK) {
1653 			ret = -EINVAL;
1654 			break;
1655 		}
1656 		sk->sk_userlocks = val | (sk->sk_userlocks &
1657 					  ~SOCK_BUF_LOCK_MASK);
1658 		break;
1659 
1660 	case SO_RESERVE_MEM:
1661 	{
1662 		int delta;
1663 
1664 		if (val < 0) {
1665 			ret = -EINVAL;
1666 			break;
1667 		}
1668 
1669 		delta = val - sk->sk_reserved_mem;
1670 		if (delta < 0)
1671 			sock_release_reserved_memory(sk, -delta);
1672 		else
1673 			ret = sock_reserve_memory(sk, delta);
1674 		break;
1675 	}
1676 
1677 	default:
1678 		ret = -ENOPROTOOPT;
1679 		break;
1680 	}
1681 	sockopt_release_sock(sk);
1682 	return ret;
1683 }
1684 
1685 int sock_setsockopt(struct socket *sock, int level, int optname,
1686 		    sockptr_t optval, unsigned int optlen)
1687 {
1688 	return sk_setsockopt(sock->sk, level, optname,
1689 			     optval, optlen);
1690 }
1691 EXPORT_SYMBOL(sock_setsockopt);
1692 
1693 static const struct cred *sk_get_peer_cred(struct sock *sk)
1694 {
1695 	const struct cred *cred;
1696 
1697 	spin_lock(&sk->sk_peer_lock);
1698 	cred = get_cred(sk->sk_peer_cred);
1699 	spin_unlock(&sk->sk_peer_lock);
1700 
1701 	return cred;
1702 }
1703 
1704 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1705 			  struct ucred *ucred)
1706 {
1707 	ucred->pid = pid_vnr(pid);
1708 	ucred->uid = ucred->gid = -1;
1709 	if (cred) {
1710 		struct user_namespace *current_ns = current_user_ns();
1711 
1712 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1713 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1714 	}
1715 }
1716 
1717 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1718 {
1719 	struct user_namespace *user_ns = current_user_ns();
1720 	int i;
1721 
1722 	for (i = 0; i < src->ngroups; i++) {
1723 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1724 
1725 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1726 			return -EFAULT;
1727 	}
1728 
1729 	return 0;
1730 }
1731 
1732 int sk_getsockopt(struct sock *sk, int level, int optname,
1733 		  sockptr_t optval, sockptr_t optlen)
1734 {
1735 	struct socket *sock = sk->sk_socket;
1736 
1737 	union {
1738 		int val;
1739 		u64 val64;
1740 		unsigned long ulval;
1741 		struct linger ling;
1742 		struct old_timeval32 tm32;
1743 		struct __kernel_old_timeval tm;
1744 		struct  __kernel_sock_timeval stm;
1745 		struct sock_txtime txtime;
1746 		struct so_timestamping timestamping;
1747 	} v;
1748 
1749 	int lv = sizeof(int);
1750 	int len;
1751 
1752 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1753 		return -EFAULT;
1754 	if (len < 0)
1755 		return -EINVAL;
1756 
1757 	memset(&v, 0, sizeof(v));
1758 
1759 	switch (optname) {
1760 	case SO_DEBUG:
1761 		v.val = sock_flag(sk, SOCK_DBG);
1762 		break;
1763 
1764 	case SO_DONTROUTE:
1765 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1766 		break;
1767 
1768 	case SO_BROADCAST:
1769 		v.val = sock_flag(sk, SOCK_BROADCAST);
1770 		break;
1771 
1772 	case SO_SNDBUF:
1773 		v.val = READ_ONCE(sk->sk_sndbuf);
1774 		break;
1775 
1776 	case SO_RCVBUF:
1777 		v.val = READ_ONCE(sk->sk_rcvbuf);
1778 		break;
1779 
1780 	case SO_REUSEADDR:
1781 		v.val = sk->sk_reuse;
1782 		break;
1783 
1784 	case SO_REUSEPORT:
1785 		v.val = sk->sk_reuseport;
1786 		break;
1787 
1788 	case SO_KEEPALIVE:
1789 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1790 		break;
1791 
1792 	case SO_TYPE:
1793 		v.val = sk->sk_type;
1794 		break;
1795 
1796 	case SO_PROTOCOL:
1797 		v.val = sk->sk_protocol;
1798 		break;
1799 
1800 	case SO_DOMAIN:
1801 		v.val = sk->sk_family;
1802 		break;
1803 
1804 	case SO_ERROR:
1805 		v.val = -sock_error(sk);
1806 		if (v.val == 0)
1807 			v.val = xchg(&sk->sk_err_soft, 0);
1808 		break;
1809 
1810 	case SO_OOBINLINE:
1811 		v.val = sock_flag(sk, SOCK_URGINLINE);
1812 		break;
1813 
1814 	case SO_NO_CHECK:
1815 		v.val = sk->sk_no_check_tx;
1816 		break;
1817 
1818 	case SO_PRIORITY:
1819 		v.val = READ_ONCE(sk->sk_priority);
1820 		break;
1821 
1822 	case SO_LINGER:
1823 		lv		= sizeof(v.ling);
1824 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1825 		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1826 		break;
1827 
1828 	case SO_BSDCOMPAT:
1829 		break;
1830 
1831 	case SO_TIMESTAMP_OLD:
1832 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1833 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1834 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1835 		break;
1836 
1837 	case SO_TIMESTAMPNS_OLD:
1838 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1839 		break;
1840 
1841 	case SO_TIMESTAMP_NEW:
1842 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1843 		break;
1844 
1845 	case SO_TIMESTAMPNS_NEW:
1846 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1847 		break;
1848 
1849 	case SO_TIMESTAMPING_OLD:
1850 	case SO_TIMESTAMPING_NEW:
1851 		lv = sizeof(v.timestamping);
1852 		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1853 		 * returning the flags when they were set through the same option.
1854 		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1855 		 */
1856 		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1857 			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1858 			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1859 		}
1860 		break;
1861 
1862 	case SO_RCVTIMEO_OLD:
1863 	case SO_RCVTIMEO_NEW:
1864 		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1865 				      SO_RCVTIMEO_OLD == optname);
1866 		break;
1867 
1868 	case SO_SNDTIMEO_OLD:
1869 	case SO_SNDTIMEO_NEW:
1870 		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1871 				      SO_SNDTIMEO_OLD == optname);
1872 		break;
1873 
1874 	case SO_RCVLOWAT:
1875 		v.val = READ_ONCE(sk->sk_rcvlowat);
1876 		break;
1877 
1878 	case SO_SNDLOWAT:
1879 		v.val = 1;
1880 		break;
1881 
1882 	case SO_PASSCRED:
1883 		if (!sk_may_scm_recv(sk))
1884 			return -EOPNOTSUPP;
1885 
1886 		v.val = sk->sk_scm_credentials;
1887 		break;
1888 
1889 	case SO_PASSPIDFD:
1890 		if (!sk_is_unix(sk))
1891 			return -EOPNOTSUPP;
1892 
1893 		v.val = sk->sk_scm_pidfd;
1894 		break;
1895 
1896 	case SO_PASSRIGHTS:
1897 		if (!sk_is_unix(sk))
1898 			return -EOPNOTSUPP;
1899 
1900 		v.val = sk->sk_scm_rights;
1901 		break;
1902 
1903 	case SO_PEERCRED:
1904 	{
1905 		struct ucred peercred;
1906 		if (len > sizeof(peercred))
1907 			len = sizeof(peercred);
1908 
1909 		spin_lock(&sk->sk_peer_lock);
1910 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1911 		spin_unlock(&sk->sk_peer_lock);
1912 
1913 		if (copy_to_sockptr(optval, &peercred, len))
1914 			return -EFAULT;
1915 		goto lenout;
1916 	}
1917 
1918 	case SO_PEERPIDFD:
1919 	{
1920 		struct pid *peer_pid;
1921 		struct file *pidfd_file = NULL;
1922 		unsigned int flags = 0;
1923 		int pidfd;
1924 
1925 		if (len > sizeof(pidfd))
1926 			len = sizeof(pidfd);
1927 
1928 		spin_lock(&sk->sk_peer_lock);
1929 		peer_pid = get_pid(sk->sk_peer_pid);
1930 		spin_unlock(&sk->sk_peer_lock);
1931 
1932 		if (!peer_pid)
1933 			return -ENODATA;
1934 
1935 		/* The use of PIDFD_STALE requires stashing of struct pid
1936 		 * on pidfs with pidfs_register_pid() and only AF_UNIX
1937 		 * were prepared for this.
1938 		 */
1939 		if (sk->sk_family == AF_UNIX)
1940 			flags = PIDFD_STALE;
1941 
1942 		pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1943 		put_pid(peer_pid);
1944 		if (pidfd < 0)
1945 			return pidfd;
1946 
1947 		if (copy_to_sockptr(optval, &pidfd, len) ||
1948 		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1949 			put_unused_fd(pidfd);
1950 			fput(pidfd_file);
1951 
1952 			return -EFAULT;
1953 		}
1954 
1955 		fd_install(pidfd, pidfd_file);
1956 		return 0;
1957 	}
1958 
1959 	case SO_PEERGROUPS:
1960 	{
1961 		const struct cred *cred;
1962 		int ret, n;
1963 
1964 		cred = sk_get_peer_cred(sk);
1965 		if (!cred)
1966 			return -ENODATA;
1967 
1968 		n = cred->group_info->ngroups;
1969 		if (len < n * sizeof(gid_t)) {
1970 			len = n * sizeof(gid_t);
1971 			put_cred(cred);
1972 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1973 		}
1974 		len = n * sizeof(gid_t);
1975 
1976 		ret = groups_to_user(optval, cred->group_info);
1977 		put_cred(cred);
1978 		if (ret)
1979 			return ret;
1980 		goto lenout;
1981 	}
1982 
1983 	case SO_PEERNAME:
1984 	{
1985 		struct sockaddr_storage address;
1986 
1987 		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1988 		if (lv < 0)
1989 			return -ENOTCONN;
1990 		if (lv < len)
1991 			return -EINVAL;
1992 		if (copy_to_sockptr(optval, &address, len))
1993 			return -EFAULT;
1994 		goto lenout;
1995 	}
1996 
1997 	/* Dubious BSD thing... Probably nobody even uses it, but
1998 	 * the UNIX standard wants it for whatever reason... -DaveM
1999 	 */
2000 	case SO_ACCEPTCONN:
2001 		v.val = sk->sk_state == TCP_LISTEN;
2002 		break;
2003 
2004 	case SO_PASSSEC:
2005 		if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk))
2006 			return -EOPNOTSUPP;
2007 
2008 		v.val = sk->sk_scm_security;
2009 		break;
2010 
2011 	case SO_PEERSEC:
2012 		return security_socket_getpeersec_stream(sock,
2013 							 optval, optlen, len);
2014 
2015 	case SO_MARK:
2016 		v.val = READ_ONCE(sk->sk_mark);
2017 		break;
2018 
2019 	case SO_RCVMARK:
2020 		v.val = sock_flag(sk, SOCK_RCVMARK);
2021 		break;
2022 
2023 	case SO_RCVPRIORITY:
2024 		v.val = sock_flag(sk, SOCK_RCVPRIORITY);
2025 		break;
2026 
2027 	case SO_RXQ_OVFL:
2028 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
2029 		break;
2030 
2031 	case SO_WIFI_STATUS:
2032 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
2033 		break;
2034 
2035 	case SO_PEEK_OFF:
2036 		if (!READ_ONCE(sock->ops)->set_peek_off)
2037 			return -EOPNOTSUPP;
2038 
2039 		v.val = READ_ONCE(sk->sk_peek_off);
2040 		break;
2041 	case SO_NOFCS:
2042 		v.val = sock_flag(sk, SOCK_NOFCS);
2043 		break;
2044 
2045 	case SO_BINDTODEVICE:
2046 		return sock_getbindtodevice(sk, optval, optlen, len);
2047 
2048 	case SO_GET_FILTER:
2049 		len = sk_get_filter(sk, optval, len);
2050 		if (len < 0)
2051 			return len;
2052 
2053 		goto lenout;
2054 
2055 	case SO_LOCK_FILTER:
2056 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2057 		break;
2058 
2059 	case SO_BPF_EXTENSIONS:
2060 		v.val = bpf_tell_extensions();
2061 		break;
2062 
2063 	case SO_SELECT_ERR_QUEUE:
2064 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2065 		break;
2066 
2067 #ifdef CONFIG_NET_RX_BUSY_POLL
2068 	case SO_BUSY_POLL:
2069 		v.val = READ_ONCE(sk->sk_ll_usec);
2070 		break;
2071 	case SO_PREFER_BUSY_POLL:
2072 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2073 		break;
2074 #endif
2075 
2076 	case SO_MAX_PACING_RATE:
2077 		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2078 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2079 			lv = sizeof(v.ulval);
2080 			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2081 		} else {
2082 			/* 32bit version */
2083 			v.val = min_t(unsigned long, ~0U,
2084 				      READ_ONCE(sk->sk_max_pacing_rate));
2085 		}
2086 		break;
2087 
2088 	case SO_INCOMING_CPU:
2089 		v.val = READ_ONCE(sk->sk_incoming_cpu);
2090 		break;
2091 
2092 	case SO_MEMINFO:
2093 	{
2094 		u32 meminfo[SK_MEMINFO_VARS];
2095 
2096 		sk_get_meminfo(sk, meminfo);
2097 
2098 		len = min_t(unsigned int, len, sizeof(meminfo));
2099 		if (copy_to_sockptr(optval, &meminfo, len))
2100 			return -EFAULT;
2101 
2102 		goto lenout;
2103 	}
2104 
2105 #ifdef CONFIG_NET_RX_BUSY_POLL
2106 	case SO_INCOMING_NAPI_ID:
2107 		v.val = READ_ONCE(sk->sk_napi_id);
2108 
2109 		/* aggregate non-NAPI IDs down to 0 */
2110 		if (!napi_id_valid(v.val))
2111 			v.val = 0;
2112 
2113 		break;
2114 #endif
2115 
2116 	case SO_COOKIE:
2117 		lv = sizeof(u64);
2118 		if (len < lv)
2119 			return -EINVAL;
2120 		v.val64 = sock_gen_cookie(sk);
2121 		break;
2122 
2123 	case SO_ZEROCOPY:
2124 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
2125 		break;
2126 
2127 	case SO_TXTIME:
2128 		lv = sizeof(v.txtime);
2129 		v.txtime.clockid = sk->sk_clockid;
2130 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2131 				  SOF_TXTIME_DEADLINE_MODE : 0;
2132 		v.txtime.flags |= sk->sk_txtime_report_errors ?
2133 				  SOF_TXTIME_REPORT_ERRORS : 0;
2134 		break;
2135 
2136 	case SO_BINDTOIFINDEX:
2137 		v.val = READ_ONCE(sk->sk_bound_dev_if);
2138 		break;
2139 
2140 	case SO_NETNS_COOKIE:
2141 		lv = sizeof(u64);
2142 		if (len != lv)
2143 			return -EINVAL;
2144 		v.val64 = sock_net(sk)->net_cookie;
2145 		break;
2146 
2147 	case SO_BUF_LOCK:
2148 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2149 		break;
2150 
2151 	case SO_RESERVE_MEM:
2152 		v.val = READ_ONCE(sk->sk_reserved_mem);
2153 		break;
2154 
2155 	case SO_TXREHASH:
2156 		if (!sk_is_tcp(sk))
2157 			return -EOPNOTSUPP;
2158 
2159 		/* Paired with WRITE_ONCE() in sk_setsockopt() */
2160 		v.val = READ_ONCE(sk->sk_txrehash);
2161 		break;
2162 
2163 	default:
2164 		/* We implement the SO_SNDLOWAT etc to not be settable
2165 		 * (1003.1g 7).
2166 		 */
2167 		return -ENOPROTOOPT;
2168 	}
2169 
2170 	if (len > lv)
2171 		len = lv;
2172 	if (copy_to_sockptr(optval, &v, len))
2173 		return -EFAULT;
2174 lenout:
2175 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2176 		return -EFAULT;
2177 	return 0;
2178 }
2179 
2180 /*
2181  * Initialize an sk_lock.
2182  *
2183  * (We also register the sk_lock with the lock validator.)
2184  */
2185 static inline void sock_lock_init(struct sock *sk)
2186 {
2187 	sk_owner_clear(sk);
2188 
2189 	if (sk->sk_kern_sock)
2190 		sock_lock_init_class_and_name(
2191 			sk,
2192 			af_family_kern_slock_key_strings[sk->sk_family],
2193 			af_family_kern_slock_keys + sk->sk_family,
2194 			af_family_kern_key_strings[sk->sk_family],
2195 			af_family_kern_keys + sk->sk_family);
2196 	else
2197 		sock_lock_init_class_and_name(
2198 			sk,
2199 			af_family_slock_key_strings[sk->sk_family],
2200 			af_family_slock_keys + sk->sk_family,
2201 			af_family_key_strings[sk->sk_family],
2202 			af_family_keys + sk->sk_family);
2203 }
2204 
2205 /*
2206  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2207  * even temporarily, because of RCU lookups. sk_node should also be left as is.
2208  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2209  */
2210 static void sock_copy(struct sock *nsk, const struct sock *osk)
2211 {
2212 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2213 #ifdef CONFIG_SECURITY_NETWORK
2214 	void *sptr = nsk->sk_security;
2215 #endif
2216 
2217 	/* If we move sk_tx_queue_mapping out of the private section,
2218 	 * we must check if sk_tx_queue_clear() is called after
2219 	 * sock_copy() in sk_clone_lock().
2220 	 */
2221 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2222 		     offsetof(struct sock, sk_dontcopy_begin) ||
2223 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2224 		     offsetof(struct sock, sk_dontcopy_end));
2225 
2226 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2227 
2228 	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2229 		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2230 		      /* alloc is larger than struct, see sk_prot_alloc() */);
2231 
2232 #ifdef CONFIG_SECURITY_NETWORK
2233 	nsk->sk_security = sptr;
2234 	security_sk_clone(osk, nsk);
2235 #endif
2236 }
2237 
2238 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2239 		int family)
2240 {
2241 	struct sock *sk;
2242 	struct kmem_cache *slab;
2243 
2244 	slab = prot->slab;
2245 	if (slab != NULL) {
2246 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2247 		if (!sk)
2248 			return sk;
2249 		if (want_init_on_alloc(priority))
2250 			sk_prot_clear_nulls(sk, prot->obj_size);
2251 	} else
2252 		sk = kmalloc(prot->obj_size, priority);
2253 
2254 	if (sk != NULL) {
2255 		if (security_sk_alloc(sk, family, priority))
2256 			goto out_free;
2257 
2258 		if (!try_module_get(prot->owner))
2259 			goto out_free_sec;
2260 	}
2261 
2262 	return sk;
2263 
2264 out_free_sec:
2265 	security_sk_free(sk);
2266 out_free:
2267 	if (slab != NULL)
2268 		kmem_cache_free(slab, sk);
2269 	else
2270 		kfree(sk);
2271 	return NULL;
2272 }
2273 
2274 static void sk_prot_free(struct proto *prot, struct sock *sk)
2275 {
2276 	struct kmem_cache *slab;
2277 	struct module *owner;
2278 
2279 	owner = prot->owner;
2280 	slab = prot->slab;
2281 
2282 	cgroup_sk_free(&sk->sk_cgrp_data);
2283 	mem_cgroup_sk_free(sk);
2284 	security_sk_free(sk);
2285 
2286 	sk_owner_put(sk);
2287 
2288 	if (slab != NULL)
2289 		kmem_cache_free(slab, sk);
2290 	else
2291 		kfree(sk);
2292 	module_put(owner);
2293 }
2294 
2295 /**
2296  *	sk_alloc - All socket objects are allocated here
2297  *	@net: the applicable net namespace
2298  *	@family: protocol family
2299  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2300  *	@prot: struct proto associated with this new sock instance
2301  *	@kern: is this to be a kernel socket?
2302  */
2303 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2304 		      struct proto *prot, int kern)
2305 {
2306 	struct sock *sk;
2307 
2308 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2309 	if (sk) {
2310 		sk->sk_family = family;
2311 		/*
2312 		 * See comment in struct sock definition to understand
2313 		 * why we need sk_prot_creator -acme
2314 		 */
2315 		sk->sk_prot = sk->sk_prot_creator = prot;
2316 
2317 		if (READ_ONCE(net->core.sysctl_bypass_prot_mem))
2318 			sk->sk_bypass_prot_mem = 1;
2319 
2320 		sk->sk_kern_sock = kern;
2321 		sock_lock_init(sk);
2322 
2323 		sk->sk_net_refcnt = kern ? 0 : 1;
2324 		if (likely(sk->sk_net_refcnt)) {
2325 			get_net_track(net, &sk->ns_tracker, priority);
2326 			sock_inuse_add(net, 1);
2327 		} else {
2328 			net_passive_inc(net);
2329 			__netns_tracker_alloc(net, &sk->ns_tracker,
2330 					      false, priority);
2331 		}
2332 
2333 		sock_net_set(sk, net);
2334 		refcount_set(&sk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2335 
2336 		mem_cgroup_sk_alloc(sk);
2337 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2338 		sock_update_classid(&sk->sk_cgrp_data);
2339 		sock_update_netprioidx(&sk->sk_cgrp_data);
2340 		sk_tx_queue_clear(sk);
2341 	}
2342 
2343 	return sk;
2344 }
2345 EXPORT_SYMBOL(sk_alloc);
2346 
2347 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2348  * grace period. This is the case for UDP sockets and TCP listeners.
2349  */
2350 static void __sk_destruct(struct rcu_head *head)
2351 {
2352 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2353 	struct net *net = sock_net(sk);
2354 	struct sk_filter *filter;
2355 
2356 	if (sk->sk_destruct)
2357 		sk->sk_destruct(sk);
2358 
2359 	filter = rcu_dereference_check(sk->sk_filter,
2360 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2361 	if (filter) {
2362 		sk_filter_uncharge(sk, filter);
2363 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2364 	}
2365 
2366 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2367 
2368 #ifdef CONFIG_BPF_SYSCALL
2369 	bpf_sk_storage_free(sk);
2370 #endif
2371 
2372 	if (atomic_read(&sk->sk_omem_alloc))
2373 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2374 			 __func__, atomic_read(&sk->sk_omem_alloc));
2375 
2376 	if (sk->sk_frag.page) {
2377 		put_page(sk->sk_frag.page);
2378 		sk->sk_frag.page = NULL;
2379 	}
2380 
2381 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2382 	put_cred(sk->sk_peer_cred);
2383 	put_pid(sk->sk_peer_pid);
2384 
2385 	if (likely(sk->sk_net_refcnt)) {
2386 		put_net_track(net, &sk->ns_tracker);
2387 	} else {
2388 		__netns_tracker_free(net, &sk->ns_tracker, false);
2389 		net_passive_dec(net);
2390 	}
2391 	sk_prot_free(sk->sk_prot_creator, sk);
2392 }
2393 
2394 void sk_net_refcnt_upgrade(struct sock *sk)
2395 {
2396 	struct net *net = sock_net(sk);
2397 
2398 	WARN_ON_ONCE(sk->sk_net_refcnt);
2399 	__netns_tracker_free(net, &sk->ns_tracker, false);
2400 	net_passive_dec(net);
2401 	sk->sk_net_refcnt = 1;
2402 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2403 	sock_inuse_add(net, 1);
2404 }
2405 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2406 
2407 void sk_destruct(struct sock *sk)
2408 {
2409 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2410 
2411 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2412 		reuseport_detach_sock(sk);
2413 		use_call_rcu = true;
2414 	}
2415 
2416 	if (use_call_rcu)
2417 		call_rcu(&sk->sk_rcu, __sk_destruct);
2418 	else
2419 		__sk_destruct(&sk->sk_rcu);
2420 }
2421 
2422 static void __sk_free(struct sock *sk)
2423 {
2424 	if (likely(sk->sk_net_refcnt))
2425 		sock_inuse_add(sock_net(sk), -1);
2426 
2427 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2428 		sock_diag_broadcast_destroy(sk);
2429 	else
2430 		sk_destruct(sk);
2431 }
2432 
2433 void sk_free(struct sock *sk)
2434 {
2435 	/*
2436 	 * We subtract one from sk_wmem_alloc and can know if
2437 	 * some packets are still in some tx queue.
2438 	 * If not null, sock_wfree() will call __sk_free(sk) later
2439 	 */
2440 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2441 		__sk_free(sk);
2442 }
2443 EXPORT_SYMBOL(sk_free);
2444 
2445 static void sk_init_common(struct sock *sk)
2446 {
2447 	skb_queue_head_init(&sk->sk_receive_queue);
2448 	skb_queue_head_init(&sk->sk_write_queue);
2449 	skb_queue_head_init(&sk->sk_error_queue);
2450 
2451 	rwlock_init(&sk->sk_callback_lock);
2452 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2453 			af_rlock_keys + sk->sk_family,
2454 			af_family_rlock_key_strings[sk->sk_family]);
2455 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2456 			af_wlock_keys + sk->sk_family,
2457 			af_family_wlock_key_strings[sk->sk_family]);
2458 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2459 			af_elock_keys + sk->sk_family,
2460 			af_family_elock_key_strings[sk->sk_family]);
2461 	if (sk->sk_kern_sock)
2462 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2463 			af_kern_callback_keys + sk->sk_family,
2464 			af_family_kern_clock_key_strings[sk->sk_family]);
2465 	else
2466 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2467 			af_callback_keys + sk->sk_family,
2468 			af_family_clock_key_strings[sk->sk_family]);
2469 }
2470 
2471 /**
2472  * sk_clone - clone a socket
2473  * @sk: the socket to clone
2474  * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2475  * @lock: if true, lock the cloned sk
2476  *
2477  * If @lock is true, the clone is locked by bh_lock_sock(), and
2478  * caller must unlock socket even in error path by bh_unlock_sock().
2479  */
2480 struct sock *sk_clone(const struct sock *sk, const gfp_t priority,
2481 		      bool lock)
2482 {
2483 	struct proto *prot = READ_ONCE(sk->sk_prot);
2484 	struct sk_filter *filter;
2485 	bool is_charged = true;
2486 	struct sock *newsk;
2487 
2488 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2489 	if (!newsk)
2490 		goto out;
2491 
2492 	sock_copy(newsk, sk);
2493 
2494 	newsk->sk_prot_creator = prot;
2495 
2496 	/* SANITY */
2497 	if (likely(newsk->sk_net_refcnt)) {
2498 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2499 		sock_inuse_add(sock_net(newsk), 1);
2500 	} else {
2501 		/* Kernel sockets are not elevating the struct net refcount.
2502 		 * Instead, use a tracker to more easily detect if a layer
2503 		 * is not properly dismantling its kernel sockets at netns
2504 		 * destroy time.
2505 		 */
2506 		net_passive_inc(sock_net(newsk));
2507 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2508 				      false, priority);
2509 	}
2510 
2511 	sk_node_init(&newsk->sk_node);
2512 	sock_lock_init(newsk);
2513 
2514 	if (lock)
2515 		bh_lock_sock(newsk);
2516 
2517 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2518 	newsk->sk_backlog.len = 0;
2519 
2520 	atomic_set(&newsk->sk_rmem_alloc, 0);
2521 
2522 	refcount_set(&newsk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2523 
2524 	atomic_set(&newsk->sk_omem_alloc, 0);
2525 	sk_init_common(newsk);
2526 
2527 	newsk->sk_dst_cache	= NULL;
2528 	newsk->sk_dst_pending_confirm = 0;
2529 	newsk->sk_wmem_queued	= 0;
2530 	newsk->sk_forward_alloc = 0;
2531 	newsk->sk_reserved_mem  = 0;
2532 	DEBUG_NET_WARN_ON_ONCE(newsk->sk_drop_counters);
2533 	sk_drops_reset(newsk);
2534 	newsk->sk_send_head	= NULL;
2535 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2536 	atomic_set(&newsk->sk_zckey, 0);
2537 
2538 	sock_reset_flag(newsk, SOCK_DONE);
2539 
2540 #ifdef CONFIG_MEMCG
2541 	/* sk->sk_memcg will be populated at accept() time */
2542 	newsk->sk_memcg = NULL;
2543 #endif
2544 
2545 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2546 
2547 	rcu_read_lock();
2548 	filter = rcu_dereference(sk->sk_filter);
2549 	if (filter != NULL)
2550 		/* though it's an empty new sock, the charging may fail
2551 		 * if sysctl_optmem_max was changed between creation of
2552 		 * original socket and cloning
2553 		 */
2554 		is_charged = sk_filter_charge(newsk, filter);
2555 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2556 	rcu_read_unlock();
2557 
2558 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2559 		/* We need to make sure that we don't uncharge the new
2560 		 * socket if we couldn't charge it in the first place
2561 		 * as otherwise we uncharge the parent's filter.
2562 		 */
2563 		if (!is_charged)
2564 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2565 
2566 		goto free;
2567 	}
2568 
2569 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2570 
2571 	if (bpf_sk_storage_clone(sk, newsk))
2572 		goto free;
2573 
2574 	/* Clear sk_user_data if parent had the pointer tagged
2575 	 * as not suitable for copying when cloning.
2576 	 */
2577 	if (sk_user_data_is_nocopy(newsk))
2578 		newsk->sk_user_data = NULL;
2579 
2580 	newsk->sk_err	   = 0;
2581 	newsk->sk_err_soft = 0;
2582 	newsk->sk_priority = 0;
2583 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2584 
2585 	/* Before updating sk_refcnt, we must commit prior changes to memory
2586 	 * (Documentation/RCU/rculist_nulls.rst for details)
2587 	 */
2588 	smp_wmb();
2589 	refcount_set(&newsk->sk_refcnt, 2);
2590 
2591 	sk_set_socket(newsk, NULL);
2592 	sk_tx_queue_clear(newsk);
2593 	sk_rx_queue_clear(newsk);
2594 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2595 
2596 	if (newsk->sk_prot->sockets_allocated)
2597 		sk_sockets_allocated_inc(newsk);
2598 
2599 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2600 		net_enable_timestamp();
2601 out:
2602 	return newsk;
2603 free:
2604 	/* It is still raw copy of parent, so invalidate
2605 	 * destructor and make plain sk_free()
2606 	 */
2607 	newsk->sk_destruct = NULL;
2608 	if (lock)
2609 		bh_unlock_sock(newsk);
2610 	sk_free(newsk);
2611 	newsk = NULL;
2612 	goto out;
2613 }
2614 EXPORT_SYMBOL_GPL(sk_clone);
2615 
2616 static u32 sk_dst_gso_max_size(struct sock *sk, const struct net_device *dev)
2617 {
2618 	bool is_ipv6 = false;
2619 	u32 max_size;
2620 
2621 #if IS_ENABLED(CONFIG_IPV6)
2622 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2623 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2624 #endif
2625 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2626 	max_size = is_ipv6 ? READ_ONCE(dev->gso_max_size) :
2627 			READ_ONCE(dev->gso_ipv4_max_size);
2628 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2629 		max_size = GSO_LEGACY_MAX_SIZE;
2630 
2631 	return max_size - (MAX_TCP_HEADER + 1);
2632 }
2633 
2634 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2635 {
2636 	const struct net_device *dev;
2637 	u32 max_segs = 1;
2638 
2639 	rcu_read_lock();
2640 	dev = dst_dev_rcu(dst);
2641 	sk->sk_route_caps = dev->features;
2642 	if (sk_is_tcp(sk)) {
2643 		struct inet_connection_sock *icsk = inet_csk(sk);
2644 
2645 		sk->sk_route_caps |= NETIF_F_GSO;
2646 		icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2647 	}
2648 	if (sk->sk_route_caps & NETIF_F_GSO)
2649 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2650 	if (unlikely(sk->sk_gso_disabled))
2651 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2652 	if (sk_can_gso(sk)) {
2653 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2654 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2655 		} else {
2656 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2657 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dev);
2658 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2659 			max_segs = max_t(u32, READ_ONCE(dev->gso_max_segs), 1);
2660 		}
2661 	}
2662 	sk->sk_gso_max_segs = max_segs;
2663 	sk_dst_set(sk, dst);
2664 	rcu_read_unlock();
2665 }
2666 EXPORT_SYMBOL_GPL(sk_setup_caps);
2667 
2668 /*
2669  *	Simple resource managers for sockets.
2670  */
2671 
2672 
2673 /*
2674  * Write buffer destructor automatically called from kfree_skb.
2675  */
2676 void sock_wfree(struct sk_buff *skb)
2677 {
2678 	unsigned int len = skb->truesize;
2679 	struct sock *sk = skb->sk;
2680 	bool free;
2681 	int old;
2682 
2683 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2684 		void (*sk_write_space)(struct sock *sk);
2685 
2686 		sk_write_space = READ_ONCE(sk->sk_write_space);
2687 
2688 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2689 		    sk_write_space == sock_def_write_space) {
2690 			rcu_read_lock();
2691 			free = __refcount_sub_and_test(len, &sk->sk_wmem_alloc,
2692 						       &old);
2693 			sock_def_write_space_wfree(sk, old - len);
2694 			rcu_read_unlock();
2695 			if (unlikely(free))
2696 				__sk_free(sk);
2697 			return;
2698 		}
2699 
2700 		/*
2701 		 * Keep a reference on sk_wmem_alloc, this will be released
2702 		 * after sk_write_space() call
2703 		 */
2704 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2705 		sk_write_space(sk);
2706 		len = 1;
2707 	}
2708 	/*
2709 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2710 	 * could not do because of in-flight packets
2711 	 */
2712 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2713 		__sk_free(sk);
2714 }
2715 EXPORT_SYMBOL(sock_wfree);
2716 
2717 /* This variant of sock_wfree() is used by TCP,
2718  * since it sets SOCK_USE_WRITE_QUEUE.
2719  */
2720 void __sock_wfree(struct sk_buff *skb)
2721 {
2722 	struct sock *sk = skb->sk;
2723 
2724 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2725 		__sk_free(sk);
2726 }
2727 
2728 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2729 {
2730 	int old_wmem;
2731 
2732 	skb_orphan(skb);
2733 #ifdef CONFIG_INET
2734 	if (unlikely(!sk_fullsock(sk)))
2735 		return skb_set_owner_edemux(skb, sk);
2736 #endif
2737 	skb->sk = sk;
2738 	skb->destructor = sock_wfree;
2739 	skb_set_hash_from_sk(skb, sk);
2740 	/*
2741 	 * We used to take a refcount on sk, but following operation
2742 	 * is enough to guarantee sk_free() won't free this sock until
2743 	 * all in-flight packets are completed
2744 	 */
2745 	__refcount_add(skb->truesize, &sk->sk_wmem_alloc, &old_wmem);
2746 
2747 	/* (old_wmem == SK_WMEM_ALLOC_BIAS) if no other TX packet for this socket
2748 	 * is in a host queue (qdisc, NIC queue).
2749 	 * Set skb->ooo_okay so that netdev_pick_tx() can choose a TX queue
2750 	 * based on XPS for better performance.
2751 	 * Otherwise clear ooo_okay to not risk Out Of Order delivery.
2752 	 */
2753 	skb->ooo_okay = (old_wmem == SK_WMEM_ALLOC_BIAS);
2754 }
2755 EXPORT_SYMBOL(skb_set_owner_w);
2756 
2757 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2758 {
2759 	/* Drivers depend on in-order delivery for crypto offload,
2760 	 * partial orphan breaks out-of-order-OK logic.
2761 	 */
2762 	if (skb_is_decrypted(skb))
2763 		return false;
2764 
2765 	return (skb->destructor == sock_wfree ||
2766 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2767 }
2768 
2769 /* This helper is used by netem, as it can hold packets in its
2770  * delay queue. We want to allow the owner socket to send more
2771  * packets, as if they were already TX completed by a typical driver.
2772  * But we also want to keep skb->sk set because some packet schedulers
2773  * rely on it (sch_fq for example).
2774  */
2775 void skb_orphan_partial(struct sk_buff *skb)
2776 {
2777 	if (skb_is_tcp_pure_ack(skb))
2778 		return;
2779 
2780 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2781 		return;
2782 
2783 	skb_orphan(skb);
2784 }
2785 EXPORT_SYMBOL(skb_orphan_partial);
2786 
2787 /*
2788  * Read buffer destructor automatically called from kfree_skb.
2789  */
2790 void sock_rfree(struct sk_buff *skb)
2791 {
2792 	struct sock *sk = skb->sk;
2793 	unsigned int len = skb->truesize;
2794 
2795 	atomic_sub(len, &sk->sk_rmem_alloc);
2796 	sk_mem_uncharge(sk, len);
2797 }
2798 EXPORT_SYMBOL(sock_rfree);
2799 
2800 /*
2801  * Buffer destructor for skbs that are not used directly in read or write
2802  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2803  */
2804 void sock_efree(struct sk_buff *skb)
2805 {
2806 	sock_put(skb->sk);
2807 }
2808 EXPORT_SYMBOL(sock_efree);
2809 
2810 /* Buffer destructor for prefetch/receive path where reference count may
2811  * not be held, e.g. for listen sockets.
2812  */
2813 #ifdef CONFIG_INET
2814 void sock_pfree(struct sk_buff *skb)
2815 {
2816 	struct sock *sk = skb->sk;
2817 
2818 	if (!sk_is_refcounted(sk))
2819 		return;
2820 
2821 	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2822 		inet_reqsk(sk)->rsk_listener = NULL;
2823 		reqsk_free(inet_reqsk(sk));
2824 		return;
2825 	}
2826 
2827 	sock_gen_put(sk);
2828 }
2829 EXPORT_SYMBOL(sock_pfree);
2830 #endif /* CONFIG_INET */
2831 
2832 /*
2833  * Allocate a skb from the socket's send buffer.
2834  */
2835 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2836 			     gfp_t priority)
2837 {
2838 	if (force ||
2839 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2840 		struct sk_buff *skb = alloc_skb(size, priority);
2841 
2842 		if (skb) {
2843 			skb_set_owner_w(skb, sk);
2844 			return skb;
2845 		}
2846 	}
2847 	return NULL;
2848 }
2849 EXPORT_SYMBOL(sock_wmalloc);
2850 
2851 static void sock_ofree(struct sk_buff *skb)
2852 {
2853 	struct sock *sk = skb->sk;
2854 
2855 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2856 }
2857 
2858 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2859 			     gfp_t priority)
2860 {
2861 	struct sk_buff *skb;
2862 
2863 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2864 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2865 	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2866 		return NULL;
2867 
2868 	skb = alloc_skb(size, priority);
2869 	if (!skb)
2870 		return NULL;
2871 
2872 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2873 	skb->sk = sk;
2874 	skb->destructor = sock_ofree;
2875 	return skb;
2876 }
2877 
2878 /*
2879  * Allocate a memory block from the socket's option memory buffer.
2880  */
2881 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2882 {
2883 	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2884 
2885 	if ((unsigned int)size <= optmem_max &&
2886 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2887 		void *mem;
2888 		/* First do the add, to avoid the race if kmalloc
2889 		 * might sleep.
2890 		 */
2891 		atomic_add(size, &sk->sk_omem_alloc);
2892 		mem = kmalloc(size, priority);
2893 		if (mem)
2894 			return mem;
2895 		atomic_sub(size, &sk->sk_omem_alloc);
2896 	}
2897 	return NULL;
2898 }
2899 EXPORT_SYMBOL(sock_kmalloc);
2900 
2901 /*
2902  * Duplicate the input "src" memory block using the socket's
2903  * option memory buffer.
2904  */
2905 void *sock_kmemdup(struct sock *sk, const void *src,
2906 		   int size, gfp_t priority)
2907 {
2908 	void *mem;
2909 
2910 	mem = sock_kmalloc(sk, size, priority);
2911 	if (mem)
2912 		memcpy(mem, src, size);
2913 	return mem;
2914 }
2915 EXPORT_SYMBOL(sock_kmemdup);
2916 
2917 /* Free an option memory block. Note, we actually want the inline
2918  * here as this allows gcc to detect the nullify and fold away the
2919  * condition entirely.
2920  */
2921 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2922 				  const bool nullify)
2923 {
2924 	if (WARN_ON_ONCE(!mem))
2925 		return;
2926 	if (nullify)
2927 		kfree_sensitive(mem);
2928 	else
2929 		kfree(mem);
2930 	atomic_sub(size, &sk->sk_omem_alloc);
2931 }
2932 
2933 void sock_kfree_s(struct sock *sk, void *mem, int size)
2934 {
2935 	__sock_kfree_s(sk, mem, size, false);
2936 }
2937 EXPORT_SYMBOL(sock_kfree_s);
2938 
2939 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2940 {
2941 	__sock_kfree_s(sk, mem, size, true);
2942 }
2943 EXPORT_SYMBOL(sock_kzfree_s);
2944 
2945 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2946    I think, these locks should be removed for datagram sockets.
2947  */
2948 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2949 {
2950 	DEFINE_WAIT(wait);
2951 
2952 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2953 	for (;;) {
2954 		if (!timeo)
2955 			break;
2956 		if (signal_pending(current))
2957 			break;
2958 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2959 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2960 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2961 			break;
2962 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2963 			break;
2964 		if (READ_ONCE(sk->sk_err))
2965 			break;
2966 		timeo = schedule_timeout(timeo);
2967 	}
2968 	finish_wait(sk_sleep(sk), &wait);
2969 	return timeo;
2970 }
2971 
2972 
2973 /*
2974  *	Generic send/receive buffer handlers
2975  */
2976 
2977 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2978 				     unsigned long data_len, int noblock,
2979 				     int *errcode, int max_page_order)
2980 {
2981 	struct sk_buff *skb;
2982 	long timeo;
2983 	int err;
2984 
2985 	timeo = sock_sndtimeo(sk, noblock);
2986 	for (;;) {
2987 		err = sock_error(sk);
2988 		if (err != 0)
2989 			goto failure;
2990 
2991 		err = -EPIPE;
2992 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2993 			goto failure;
2994 
2995 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2996 			break;
2997 
2998 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2999 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
3000 		err = -EAGAIN;
3001 		if (!timeo)
3002 			goto failure;
3003 		if (signal_pending(current))
3004 			goto interrupted;
3005 		timeo = sock_wait_for_wmem(sk, timeo);
3006 	}
3007 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
3008 				   errcode, sk->sk_allocation);
3009 	if (skb)
3010 		skb_set_owner_w(skb, sk);
3011 	return skb;
3012 
3013 interrupted:
3014 	err = sock_intr_errno(timeo);
3015 failure:
3016 	*errcode = err;
3017 	return NULL;
3018 }
3019 EXPORT_SYMBOL(sock_alloc_send_pskb);
3020 
3021 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
3022 		     struct sockcm_cookie *sockc)
3023 {
3024 	u32 tsflags;
3025 
3026 	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
3027 
3028 	switch (cmsg->cmsg_type) {
3029 	case SO_MARK:
3030 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
3031 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
3032 			return -EPERM;
3033 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3034 			return -EINVAL;
3035 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
3036 		break;
3037 	case SO_TIMESTAMPING_OLD:
3038 	case SO_TIMESTAMPING_NEW:
3039 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3040 			return -EINVAL;
3041 
3042 		tsflags = *(u32 *)CMSG_DATA(cmsg);
3043 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
3044 			return -EINVAL;
3045 
3046 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
3047 		sockc->tsflags |= tsflags;
3048 		break;
3049 	case SCM_TXTIME:
3050 		if (!sock_flag(sk, SOCK_TXTIME))
3051 			return -EINVAL;
3052 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3053 			return -EINVAL;
3054 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
3055 		break;
3056 	case SCM_TS_OPT_ID:
3057 		if (sk_is_tcp(sk))
3058 			return -EINVAL;
3059 		tsflags = READ_ONCE(sk->sk_tsflags);
3060 		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3061 			return -EINVAL;
3062 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3063 			return -EINVAL;
3064 		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3065 		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3066 		break;
3067 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3068 	case SCM_RIGHTS:
3069 	case SCM_CREDENTIALS:
3070 		break;
3071 	case SO_PRIORITY:
3072 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3073 			return -EINVAL;
3074 		if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3075 			return -EPERM;
3076 		sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3077 		break;
3078 	case SCM_DEVMEM_DMABUF:
3079 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3080 			return -EINVAL;
3081 		sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3082 		break;
3083 	default:
3084 		return -EINVAL;
3085 	}
3086 	return 0;
3087 }
3088 EXPORT_SYMBOL(__sock_cmsg_send);
3089 
3090 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3091 		   struct sockcm_cookie *sockc)
3092 {
3093 	struct cmsghdr *cmsg;
3094 	int ret;
3095 
3096 	for_each_cmsghdr(cmsg, msg) {
3097 		if (!CMSG_OK(msg, cmsg))
3098 			return -EINVAL;
3099 		if (cmsg->cmsg_level != SOL_SOCKET)
3100 			continue;
3101 		ret = __sock_cmsg_send(sk, cmsg, sockc);
3102 		if (ret)
3103 			return ret;
3104 	}
3105 	return 0;
3106 }
3107 EXPORT_SYMBOL(sock_cmsg_send);
3108 
3109 static void sk_enter_memory_pressure(struct sock *sk)
3110 {
3111 	if (!sk->sk_prot->enter_memory_pressure)
3112 		return;
3113 
3114 	sk->sk_prot->enter_memory_pressure(sk);
3115 }
3116 
3117 static void sk_leave_memory_pressure(struct sock *sk)
3118 {
3119 	if (sk->sk_prot->leave_memory_pressure) {
3120 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3121 				     tcp_leave_memory_pressure, sk);
3122 	} else {
3123 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3124 
3125 		if (memory_pressure && READ_ONCE(*memory_pressure))
3126 			WRITE_ONCE(*memory_pressure, 0);
3127 	}
3128 }
3129 
3130 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3131 
3132 /**
3133  * skb_page_frag_refill - check that a page_frag contains enough room
3134  * @sz: minimum size of the fragment we want to get
3135  * @pfrag: pointer to page_frag
3136  * @gfp: priority for memory allocation
3137  *
3138  * Note: While this allocator tries to use high order pages, there is
3139  * no guarantee that allocations succeed. Therefore, @sz MUST be
3140  * less or equal than PAGE_SIZE.
3141  */
3142 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3143 {
3144 	if (pfrag->page) {
3145 		if (page_ref_count(pfrag->page) == 1) {
3146 			pfrag->offset = 0;
3147 			return true;
3148 		}
3149 		if (pfrag->offset + sz <= pfrag->size)
3150 			return true;
3151 		put_page(pfrag->page);
3152 	}
3153 
3154 	pfrag->offset = 0;
3155 	if (SKB_FRAG_PAGE_ORDER &&
3156 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3157 		/* Avoid direct reclaim but allow kswapd to wake */
3158 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3159 					  __GFP_COMP | __GFP_NOWARN |
3160 					  __GFP_NORETRY,
3161 					  SKB_FRAG_PAGE_ORDER);
3162 		if (likely(pfrag->page)) {
3163 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3164 			return true;
3165 		}
3166 	}
3167 	pfrag->page = alloc_page(gfp);
3168 	if (likely(pfrag->page)) {
3169 		pfrag->size = PAGE_SIZE;
3170 		return true;
3171 	}
3172 	return false;
3173 }
3174 EXPORT_SYMBOL(skb_page_frag_refill);
3175 
3176 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3177 {
3178 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3179 		return true;
3180 
3181 	if (!sk->sk_bypass_prot_mem)
3182 		sk_enter_memory_pressure(sk);
3183 
3184 	sk_stream_moderate_sndbuf(sk);
3185 
3186 	return false;
3187 }
3188 EXPORT_SYMBOL(sk_page_frag_refill);
3189 
3190 static void __lock_sock(struct sock *sk)
3191 	__releases(&sk->sk_lock.slock)
3192 	__acquires(&sk->sk_lock.slock)
3193 {
3194 	DEFINE_WAIT(wait);
3195 
3196 	for (;;) {
3197 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3198 					TASK_UNINTERRUPTIBLE);
3199 		spin_unlock_bh(&sk->sk_lock.slock);
3200 		schedule();
3201 		spin_lock_bh(&sk->sk_lock.slock);
3202 		if (!sock_owned_by_user(sk))
3203 			break;
3204 	}
3205 	finish_wait(&sk->sk_lock.wq, &wait);
3206 }
3207 
3208 void __release_sock(struct sock *sk)
3209 	__releases(&sk->sk_lock.slock)
3210 	__acquires(&sk->sk_lock.slock)
3211 {
3212 	struct sk_buff *skb, *next;
3213 	int nb = 0;
3214 
3215 	while ((skb = sk->sk_backlog.head) != NULL) {
3216 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3217 
3218 		spin_unlock_bh(&sk->sk_lock.slock);
3219 
3220 		while (1) {
3221 			next = skb->next;
3222 			prefetch(next);
3223 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3224 			skb_mark_not_on_list(skb);
3225 			sk_backlog_rcv(sk, skb);
3226 
3227 			skb = next;
3228 			if (!skb)
3229 				break;
3230 
3231 			if (!(++nb & 15))
3232 				cond_resched();
3233 		}
3234 
3235 		spin_lock_bh(&sk->sk_lock.slock);
3236 	}
3237 
3238 	/*
3239 	 * Doing the zeroing here guarantee we can not loop forever
3240 	 * while a wild producer attempts to flood us.
3241 	 */
3242 	sk->sk_backlog.len = 0;
3243 }
3244 
3245 void __sk_flush_backlog(struct sock *sk)
3246 {
3247 	spin_lock_bh(&sk->sk_lock.slock);
3248 	__release_sock(sk);
3249 
3250 	if (sk->sk_prot->release_cb)
3251 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3252 				     tcp_release_cb, sk);
3253 
3254 	spin_unlock_bh(&sk->sk_lock.slock);
3255 }
3256 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3257 
3258 /**
3259  * sk_wait_data - wait for data to arrive at sk_receive_queue
3260  * @sk:    sock to wait on
3261  * @timeo: for how long
3262  * @skb:   last skb seen on sk_receive_queue
3263  *
3264  * Now socket state including sk->sk_err is changed only under lock,
3265  * hence we may omit checks after joining wait queue.
3266  * We check receive queue before schedule() only as optimization;
3267  * it is very likely that release_sock() added new data.
3268  */
3269 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3270 {
3271 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3272 	int rc;
3273 
3274 	add_wait_queue(sk_sleep(sk), &wait);
3275 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3276 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3277 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3278 	remove_wait_queue(sk_sleep(sk), &wait);
3279 	return rc;
3280 }
3281 EXPORT_SYMBOL(sk_wait_data);
3282 
3283 /**
3284  *	__sk_mem_raise_allocated - increase memory_allocated
3285  *	@sk: socket
3286  *	@size: memory size to allocate
3287  *	@amt: pages to allocate
3288  *	@kind: allocation type
3289  *
3290  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3291  *
3292  *	Unlike the globally shared limits among the sockets under same protocol,
3293  *	consuming the budget of a memcg won't have direct effect on other ones.
3294  *	So be optimistic about memcg's tolerance, and leave the callers to decide
3295  *	whether or not to raise allocated through sk_under_memory_pressure() or
3296  *	its variants.
3297  */
3298 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3299 {
3300 	bool memcg_enabled = false, charged = false;
3301 	struct proto *prot = sk->sk_prot;
3302 	long allocated = 0;
3303 
3304 	if (!sk->sk_bypass_prot_mem) {
3305 		sk_memory_allocated_add(sk, amt);
3306 		allocated = sk_memory_allocated(sk);
3307 	}
3308 
3309 	if (mem_cgroup_sk_enabled(sk)) {
3310 		memcg_enabled = true;
3311 		charged = mem_cgroup_sk_charge(sk, amt, gfp_memcg_charge());
3312 		if (!charged)
3313 			goto suppress_allocation;
3314 	}
3315 
3316 	if (!allocated)
3317 		return 1;
3318 
3319 	/* Under limit. */
3320 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3321 		sk_leave_memory_pressure(sk);
3322 		return 1;
3323 	}
3324 
3325 	/* Under pressure. */
3326 	if (allocated > sk_prot_mem_limits(sk, 1))
3327 		sk_enter_memory_pressure(sk);
3328 
3329 	/* Over hard limit. */
3330 	if (allocated > sk_prot_mem_limits(sk, 2))
3331 		goto suppress_allocation;
3332 
3333 	/* Guarantee minimum buffer size under pressure (either global
3334 	 * or memcg) to make sure features described in RFC 7323 (TCP
3335 	 * Extensions for High Performance) work properly.
3336 	 *
3337 	 * This rule does NOT stand when exceeds global or memcg's hard
3338 	 * limit, or else a DoS attack can be taken place by spawning
3339 	 * lots of sockets whose usage are under minimum buffer size.
3340 	 */
3341 	if (kind == SK_MEM_RECV) {
3342 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3343 			return 1;
3344 
3345 	} else { /* SK_MEM_SEND */
3346 		int wmem0 = sk_get_wmem0(sk, prot);
3347 
3348 		if (sk->sk_type == SOCK_STREAM) {
3349 			if (sk->sk_wmem_queued < wmem0)
3350 				return 1;
3351 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3352 				return 1;
3353 		}
3354 	}
3355 
3356 	if (sk_has_memory_pressure(sk)) {
3357 		u64 alloc;
3358 
3359 		/* The following 'average' heuristic is within the
3360 		 * scope of global accounting, so it only makes
3361 		 * sense for global memory pressure.
3362 		 */
3363 		if (!sk_under_global_memory_pressure(sk))
3364 			return 1;
3365 
3366 		/* Try to be fair among all the sockets under global
3367 		 * pressure by allowing the ones that below average
3368 		 * usage to raise.
3369 		 */
3370 		alloc = sk_sockets_allocated_read_positive(sk);
3371 		if (sk_prot_mem_limits(sk, 2) > alloc *
3372 		    sk_mem_pages(sk->sk_wmem_queued +
3373 				 atomic_read(&sk->sk_rmem_alloc) +
3374 				 sk->sk_forward_alloc))
3375 			return 1;
3376 	}
3377 
3378 suppress_allocation:
3379 
3380 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3381 		sk_stream_moderate_sndbuf(sk);
3382 
3383 		/* Fail only if socket is _under_ its sndbuf.
3384 		 * In this case we cannot block, so that we have to fail.
3385 		 */
3386 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3387 			/* Force charge with __GFP_NOFAIL */
3388 			if (memcg_enabled && !charged)
3389 				mem_cgroup_sk_charge(sk, amt,
3390 						     gfp_memcg_charge() | __GFP_NOFAIL);
3391 			return 1;
3392 		}
3393 	}
3394 
3395 	trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3396 
3397 	if (allocated)
3398 		sk_memory_allocated_sub(sk, amt);
3399 
3400 	if (charged)
3401 		mem_cgroup_sk_uncharge(sk, amt);
3402 
3403 	return 0;
3404 }
3405 
3406 /**
3407  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3408  *	@sk: socket
3409  *	@size: memory size to allocate
3410  *	@kind: allocation type
3411  *
3412  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3413  *	rmem allocation. This function assumes that protocols which have
3414  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3415  */
3416 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3417 {
3418 	int ret, amt = sk_mem_pages(size);
3419 
3420 	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3421 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3422 	if (!ret)
3423 		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3424 	return ret;
3425 }
3426 EXPORT_SYMBOL(__sk_mem_schedule);
3427 
3428 /**
3429  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3430  *	@sk: socket
3431  *	@amount: number of quanta
3432  *
3433  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3434  */
3435 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3436 {
3437 	if (mem_cgroup_sk_enabled(sk))
3438 		mem_cgroup_sk_uncharge(sk, amount);
3439 
3440 	if (sk->sk_bypass_prot_mem)
3441 		return;
3442 
3443 	sk_memory_allocated_sub(sk, amount);
3444 
3445 	if (sk_under_global_memory_pressure(sk) &&
3446 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3447 		sk_leave_memory_pressure(sk);
3448 }
3449 
3450 /**
3451  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3452  *	@sk: socket
3453  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3454  */
3455 void __sk_mem_reclaim(struct sock *sk, int amount)
3456 {
3457 	amount >>= PAGE_SHIFT;
3458 	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3459 	__sk_mem_reduce_allocated(sk, amount);
3460 }
3461 EXPORT_SYMBOL(__sk_mem_reclaim);
3462 
3463 void __sk_charge(struct sock *sk, gfp_t gfp)
3464 {
3465 	int amt;
3466 
3467 	gfp |= __GFP_NOFAIL;
3468 	if (mem_cgroup_from_sk(sk)) {
3469 		/* The socket has not been accepted yet, no need
3470 		 * to look at newsk->sk_wmem_queued.
3471 		 */
3472 		amt = sk_mem_pages(sk->sk_forward_alloc +
3473 				   atomic_read(&sk->sk_rmem_alloc));
3474 		if (amt)
3475 			mem_cgroup_sk_charge(sk, amt, gfp);
3476 	}
3477 
3478 	kmem_cache_charge(sk, gfp);
3479 }
3480 
3481 int sk_set_peek_off(struct sock *sk, int val)
3482 {
3483 	WRITE_ONCE(sk->sk_peek_off, val);
3484 	return 0;
3485 }
3486 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3487 
3488 /*
3489  * Set of default routines for initialising struct proto_ops when
3490  * the protocol does not support a particular function. In certain
3491  * cases where it makes no sense for a protocol to have a "do nothing"
3492  * function, some default processing is provided.
3493  */
3494 
3495 int sock_no_bind(struct socket *sock, struct sockaddr_unsized *saddr, int len)
3496 {
3497 	return -EOPNOTSUPP;
3498 }
3499 EXPORT_SYMBOL(sock_no_bind);
3500 
3501 int sock_no_connect(struct socket *sock, struct sockaddr_unsized *saddr,
3502 		    int len, int flags)
3503 {
3504 	return -EOPNOTSUPP;
3505 }
3506 EXPORT_SYMBOL(sock_no_connect);
3507 
3508 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3509 {
3510 	return -EOPNOTSUPP;
3511 }
3512 EXPORT_SYMBOL(sock_no_socketpair);
3513 
3514 int sock_no_accept(struct socket *sock, struct socket *newsock,
3515 		   struct proto_accept_arg *arg)
3516 {
3517 	return -EOPNOTSUPP;
3518 }
3519 EXPORT_SYMBOL(sock_no_accept);
3520 
3521 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3522 		    int peer)
3523 {
3524 	return -EOPNOTSUPP;
3525 }
3526 EXPORT_SYMBOL(sock_no_getname);
3527 
3528 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3529 {
3530 	return -EOPNOTSUPP;
3531 }
3532 EXPORT_SYMBOL(sock_no_ioctl);
3533 
3534 int sock_no_listen(struct socket *sock, int backlog)
3535 {
3536 	return -EOPNOTSUPP;
3537 }
3538 EXPORT_SYMBOL(sock_no_listen);
3539 
3540 int sock_no_shutdown(struct socket *sock, int how)
3541 {
3542 	return -EOPNOTSUPP;
3543 }
3544 EXPORT_SYMBOL(sock_no_shutdown);
3545 
3546 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3547 {
3548 	return -EOPNOTSUPP;
3549 }
3550 EXPORT_SYMBOL(sock_no_sendmsg);
3551 
3552 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3553 {
3554 	return -EOPNOTSUPP;
3555 }
3556 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3557 
3558 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3559 		    int flags)
3560 {
3561 	return -EOPNOTSUPP;
3562 }
3563 EXPORT_SYMBOL(sock_no_recvmsg);
3564 
3565 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3566 {
3567 	/* Mirror missing mmap method error code */
3568 	return -ENODEV;
3569 }
3570 EXPORT_SYMBOL(sock_no_mmap);
3571 
3572 /*
3573  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3574  * various sock-based usage counts.
3575  */
3576 void __receive_sock(struct file *file)
3577 {
3578 	struct socket *sock;
3579 
3580 	sock = sock_from_file(file);
3581 	if (sock) {
3582 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3583 		sock_update_classid(&sock->sk->sk_cgrp_data);
3584 	}
3585 }
3586 
3587 /*
3588  *	Default Socket Callbacks
3589  */
3590 
3591 static void sock_def_wakeup(struct sock *sk)
3592 {
3593 	struct socket_wq *wq;
3594 
3595 	rcu_read_lock();
3596 	wq = rcu_dereference(sk->sk_wq);
3597 	if (skwq_has_sleeper(wq))
3598 		wake_up_interruptible_all(&wq->wait);
3599 	rcu_read_unlock();
3600 }
3601 
3602 static void sock_def_error_report(struct sock *sk)
3603 {
3604 	struct socket_wq *wq;
3605 
3606 	rcu_read_lock();
3607 	wq = rcu_dereference(sk->sk_wq);
3608 	if (skwq_has_sleeper(wq))
3609 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3610 	sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3611 	rcu_read_unlock();
3612 }
3613 
3614 void sock_def_readable(struct sock *sk)
3615 {
3616 	struct socket_wq *wq;
3617 
3618 	trace_sk_data_ready(sk);
3619 
3620 	rcu_read_lock();
3621 	wq = rcu_dereference(sk->sk_wq);
3622 	if (skwq_has_sleeper(wq))
3623 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3624 						EPOLLRDNORM | EPOLLRDBAND);
3625 	sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3626 	rcu_read_unlock();
3627 }
3628 
3629 static void sock_def_write_space(struct sock *sk)
3630 {
3631 	struct socket_wq *wq;
3632 
3633 	rcu_read_lock();
3634 
3635 	/* Do not wake up a writer until he can make "significant"
3636 	 * progress.  --DaveM
3637 	 */
3638 	if (sock_writeable(sk)) {
3639 		wq = rcu_dereference(sk->sk_wq);
3640 		if (skwq_has_sleeper(wq))
3641 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3642 						EPOLLWRNORM | EPOLLWRBAND);
3643 
3644 		/* Should agree with poll, otherwise some programs break */
3645 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3646 	}
3647 
3648 	rcu_read_unlock();
3649 }
3650 
3651 /* An optimised version of sock_def_write_space(), should only be called
3652  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3653  * ->sk_wmem_alloc.
3654  */
3655 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc)
3656 {
3657 	/* Do not wake up a writer until he can make "significant"
3658 	 * progress.  --DaveM
3659 	 */
3660 	if (__sock_writeable(sk, wmem_alloc)) {
3661 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3662 
3663 		/* rely on refcount_sub from sock_wfree() */
3664 		smp_mb__after_atomic();
3665 		if (wq && waitqueue_active(&wq->wait))
3666 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3667 						EPOLLWRNORM | EPOLLWRBAND);
3668 
3669 		/* Should agree with poll, otherwise some programs break */
3670 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3671 	}
3672 }
3673 
3674 static void sock_def_destruct(struct sock *sk)
3675 {
3676 }
3677 
3678 void sk_send_sigurg(struct sock *sk)
3679 {
3680 	if (sk->sk_socket && sk->sk_socket->file)
3681 		if (send_sigurg(sk->sk_socket->file))
3682 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3683 }
3684 EXPORT_SYMBOL(sk_send_sigurg);
3685 
3686 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3687 		    unsigned long expires)
3688 {
3689 	if (!mod_timer(timer, expires))
3690 		sock_hold(sk);
3691 }
3692 EXPORT_SYMBOL(sk_reset_timer);
3693 
3694 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3695 {
3696 	if (timer_delete(timer))
3697 		__sock_put(sk);
3698 }
3699 EXPORT_SYMBOL(sk_stop_timer);
3700 
3701 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3702 {
3703 	if (timer_delete_sync(timer))
3704 		__sock_put(sk);
3705 }
3706 EXPORT_SYMBOL(sk_stop_timer_sync);
3707 
3708 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3709 {
3710 	sk_init_common(sk);
3711 	sk->sk_send_head	=	NULL;
3712 
3713 	timer_setup(&sk->sk_timer, NULL, 0);
3714 
3715 	sk->sk_allocation	=	GFP_KERNEL;
3716 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3717 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3718 	sk->sk_state		=	TCP_CLOSE;
3719 	sk->sk_use_task_frag	=	true;
3720 	sk_set_socket(sk, sock);
3721 
3722 	sock_set_flag(sk, SOCK_ZAPPED);
3723 
3724 	if (sock) {
3725 		sk->sk_type	=	sock->type;
3726 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3727 		sock->sk	=	sk;
3728 	} else {
3729 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3730 	}
3731 	sk->sk_uid	=	uid;
3732 
3733 	sk->sk_state_change	=	sock_def_wakeup;
3734 	sk->sk_data_ready	=	sock_def_readable;
3735 	sk->sk_write_space	=	sock_def_write_space;
3736 	sk->sk_error_report	=	sock_def_error_report;
3737 	sk->sk_destruct		=	sock_def_destruct;
3738 
3739 	sk->sk_frag.page	=	NULL;
3740 	sk->sk_frag.offset	=	0;
3741 	sk->sk_peek_off		=	-1;
3742 
3743 	sk->sk_peer_pid 	=	NULL;
3744 	sk->sk_peer_cred	=	NULL;
3745 	spin_lock_init(&sk->sk_peer_lock);
3746 
3747 	sk->sk_write_pending	=	0;
3748 	sk->sk_rcvlowat		=	1;
3749 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3750 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3751 
3752 	sk->sk_stamp = SK_DEFAULT_STAMP;
3753 #if BITS_PER_LONG==32
3754 	seqlock_init(&sk->sk_stamp_seq);
3755 #endif
3756 	atomic_set(&sk->sk_zckey, 0);
3757 
3758 #ifdef CONFIG_NET_RX_BUSY_POLL
3759 	sk->sk_napi_id		=	0;
3760 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3761 #endif
3762 
3763 	sk->sk_max_pacing_rate = ~0UL;
3764 	sk->sk_pacing_rate = ~0UL;
3765 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3766 	sk->sk_incoming_cpu = -1;
3767 
3768 	sk_rx_queue_clear(sk);
3769 	/*
3770 	 * Before updating sk_refcnt, we must commit prior changes to memory
3771 	 * (Documentation/RCU/rculist_nulls.rst for details)
3772 	 */
3773 	smp_wmb();
3774 	refcount_set(&sk->sk_refcnt, 1);
3775 	sk_drops_reset(sk);
3776 }
3777 EXPORT_SYMBOL(sock_init_data_uid);
3778 
3779 void sock_init_data(struct socket *sock, struct sock *sk)
3780 {
3781 	kuid_t uid = sock ?
3782 		SOCK_INODE(sock)->i_uid :
3783 		make_kuid(sock_net(sk)->user_ns, 0);
3784 
3785 	sock_init_data_uid(sock, sk, uid);
3786 }
3787 EXPORT_SYMBOL(sock_init_data);
3788 
3789 void noinline lock_sock_nested(struct sock *sk, int subclass)
3790 {
3791 	/* The sk_lock has mutex_lock() semantics here. */
3792 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3793 
3794 	might_sleep();
3795 #ifdef CONFIG_64BIT
3796 	if (sizeof(struct slock_owned) == sizeof(long)) {
3797 		socket_lock_t tmp = {
3798 			.slock = __SPIN_LOCK_UNLOCKED(tmp.slock),
3799 			.owned = 1,
3800 		};
3801 		socket_lock_t old = {
3802 			.slock = __SPIN_LOCK_UNLOCKED(old.slock),
3803 			.owned = 0,
3804 		};
3805 
3806 		if (likely(try_cmpxchg(&sk->sk_lock.combined,
3807 				       &old.combined, tmp.combined)))
3808 			return;
3809 	}
3810 #endif
3811 	spin_lock_bh(&sk->sk_lock.slock);
3812 	if (unlikely(sock_owned_by_user_nocheck(sk)))
3813 		__lock_sock(sk);
3814 	sk->sk_lock.owned = 1;
3815 	spin_unlock_bh(&sk->sk_lock.slock);
3816 }
3817 EXPORT_SYMBOL(lock_sock_nested);
3818 
3819 void release_sock(struct sock *sk)
3820 {
3821 	spin_lock_bh(&sk->sk_lock.slock);
3822 
3823 	if (unlikely(sk->sk_backlog.tail))
3824 		__release_sock(sk);
3825 
3826 	if (sk->sk_prot->release_cb) {
3827 		if (!tcp_release_cb_cond(sk))
3828 			sk->sk_prot->release_cb(sk);
3829 	}
3830 	sock_release_ownership(sk);
3831 	if (unlikely(waitqueue_active(&sk->sk_lock.wq)))
3832 		wake_up(&sk->sk_lock.wq);
3833 
3834 	spin_unlock_bh(&sk->sk_lock.slock);
3835 }
3836 EXPORT_SYMBOL(release_sock);
3837 
3838 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3839 {
3840 	might_sleep();
3841 	spin_lock_bh(&sk->sk_lock.slock);
3842 
3843 	if (likely(!sock_owned_by_user_nocheck(sk))) {
3844 		/*
3845 		 * Fast path return with bottom halves disabled and
3846 		 * sock::sk_lock.slock held.
3847 		 *
3848 		 * The 'mutex' is not contended and holding
3849 		 * sock::sk_lock.slock prevents all other lockers to
3850 		 * proceed so the corresponding unlock_sock_fast() can
3851 		 * avoid the slow path of release_sock() completely and
3852 		 * just release slock.
3853 		 *
3854 		 * From a semantical POV this is equivalent to 'acquiring'
3855 		 * the 'mutex', hence the corresponding lockdep
3856 		 * mutex_release() has to happen in the fast path of
3857 		 * unlock_sock_fast().
3858 		 */
3859 		return false;
3860 	}
3861 
3862 	__lock_sock(sk);
3863 	sk->sk_lock.owned = 1;
3864 	__acquire(&sk->sk_lock.slock);
3865 	spin_unlock_bh(&sk->sk_lock.slock);
3866 	return true;
3867 }
3868 EXPORT_SYMBOL(__lock_sock_fast);
3869 
3870 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3871 		   bool timeval, bool time32)
3872 {
3873 	struct sock *sk = sock->sk;
3874 	struct timespec64 ts;
3875 
3876 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3877 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3878 	if (ts.tv_sec == -1)
3879 		return -ENOENT;
3880 	if (ts.tv_sec == 0) {
3881 		ktime_t kt = ktime_get_real();
3882 		sock_write_timestamp(sk, kt);
3883 		ts = ktime_to_timespec64(kt);
3884 	}
3885 
3886 	if (timeval)
3887 		ts.tv_nsec /= 1000;
3888 
3889 #ifdef CONFIG_COMPAT_32BIT_TIME
3890 	if (time32)
3891 		return put_old_timespec32(&ts, userstamp);
3892 #endif
3893 #ifdef CONFIG_SPARC64
3894 	/* beware of padding in sparc64 timeval */
3895 	if (timeval && !in_compat_syscall()) {
3896 		struct __kernel_old_timeval __user tv = {
3897 			.tv_sec = ts.tv_sec,
3898 			.tv_usec = ts.tv_nsec,
3899 		};
3900 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3901 			return -EFAULT;
3902 		return 0;
3903 	}
3904 #endif
3905 	return put_timespec64(&ts, userstamp);
3906 }
3907 EXPORT_SYMBOL(sock_gettstamp);
3908 
3909 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3910 {
3911 	if (!sock_flag(sk, flag)) {
3912 		unsigned long previous_flags = sk->sk_flags;
3913 
3914 		sock_set_flag(sk, flag);
3915 		/*
3916 		 * we just set one of the two flags which require net
3917 		 * time stamping, but time stamping might have been on
3918 		 * already because of the other one
3919 		 */
3920 		if (sock_needs_netstamp(sk) &&
3921 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3922 			net_enable_timestamp();
3923 	}
3924 }
3925 
3926 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3927 		       int level, int type)
3928 {
3929 	struct sock_extended_err ee;
3930 	struct sk_buff *skb;
3931 	int copied, err;
3932 
3933 	err = -EAGAIN;
3934 	skb = sock_dequeue_err_skb(sk);
3935 	if (skb == NULL)
3936 		goto out;
3937 
3938 	copied = skb->len;
3939 	if (copied > len) {
3940 		msg->msg_flags |= MSG_TRUNC;
3941 		copied = len;
3942 	}
3943 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3944 	if (err)
3945 		goto out_free_skb;
3946 
3947 	sock_recv_timestamp(msg, sk, skb);
3948 
3949 	/* We must use a bounce buffer for CONFIG_HARDENED_USERCOPY=y */
3950 	ee = SKB_EXT_ERR(skb)->ee;
3951 	put_cmsg(msg, level, type, sizeof(ee), &ee);
3952 
3953 	msg->msg_flags |= MSG_ERRQUEUE;
3954 	err = copied;
3955 
3956 out_free_skb:
3957 	kfree_skb(skb);
3958 out:
3959 	return err;
3960 }
3961 EXPORT_SYMBOL(sock_recv_errqueue);
3962 
3963 /*
3964  *	Get a socket option on an socket.
3965  *
3966  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3967  *	asynchronous errors should be reported by getsockopt. We assume
3968  *	this means if you specify SO_ERROR (otherwise what is the point of it).
3969  */
3970 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3971 			   char __user *optval, int __user *optlen)
3972 {
3973 	struct sock *sk = sock->sk;
3974 
3975 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3976 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3977 }
3978 EXPORT_SYMBOL(sock_common_getsockopt);
3979 
3980 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3981 			int flags)
3982 {
3983 	struct sock *sk = sock->sk;
3984 
3985 	return sk->sk_prot->recvmsg(sk, msg, size, flags);
3986 }
3987 EXPORT_SYMBOL(sock_common_recvmsg);
3988 
3989 /*
3990  *	Set socket options on an inet socket.
3991  */
3992 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3993 			   sockptr_t optval, unsigned int optlen)
3994 {
3995 	struct sock *sk = sock->sk;
3996 
3997 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3998 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3999 }
4000 EXPORT_SYMBOL(sock_common_setsockopt);
4001 
4002 void sk_common_release(struct sock *sk)
4003 {
4004 	if (sk->sk_prot->destroy)
4005 		sk->sk_prot->destroy(sk);
4006 
4007 	/*
4008 	 * Observation: when sk_common_release is called, processes have
4009 	 * no access to socket. But net still has.
4010 	 * Step one, detach it from networking:
4011 	 *
4012 	 * A. Remove from hash tables.
4013 	 */
4014 
4015 	sk->sk_prot->unhash(sk);
4016 
4017 	/*
4018 	 * In this point socket cannot receive new packets, but it is possible
4019 	 * that some packets are in flight because some CPU runs receiver and
4020 	 * did hash table lookup before we unhashed socket. They will achieve
4021 	 * receive queue and will be purged by socket destructor.
4022 	 *
4023 	 * Also we still have packets pending on receive queue and probably,
4024 	 * our own packets waiting in device queues. sock_destroy will drain
4025 	 * receive queue, but transmitted packets will delay socket destruction
4026 	 * until the last reference will be released.
4027 	 */
4028 
4029 	sock_orphan(sk);
4030 
4031 	xfrm_sk_free_policy(sk);
4032 
4033 	sock_put(sk);
4034 }
4035 EXPORT_SYMBOL(sk_common_release);
4036 
4037 void sk_get_meminfo(const struct sock *sk, u32 *mem)
4038 {
4039 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
4040 
4041 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
4042 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
4043 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
4044 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
4045 	mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
4046 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
4047 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
4048 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
4049 	mem[SK_MEMINFO_DROPS] = sk_drops_read(sk);
4050 }
4051 
4052 #ifdef CONFIG_PROC_FS
4053 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
4054 
4055 int sock_prot_inuse_get(struct net *net, struct proto *prot)
4056 {
4057 	int cpu, idx = prot->inuse_idx;
4058 	int res = 0;
4059 
4060 	for_each_possible_cpu(cpu)
4061 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
4062 
4063 	return res >= 0 ? res : 0;
4064 }
4065 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
4066 
4067 int sock_inuse_get(struct net *net)
4068 {
4069 	int cpu, res = 0;
4070 
4071 	for_each_possible_cpu(cpu)
4072 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
4073 
4074 	return res;
4075 }
4076 
4077 EXPORT_SYMBOL_GPL(sock_inuse_get);
4078 
4079 static int __net_init sock_inuse_init_net(struct net *net)
4080 {
4081 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
4082 	if (net->core.prot_inuse == NULL)
4083 		return -ENOMEM;
4084 	return 0;
4085 }
4086 
4087 static void __net_exit sock_inuse_exit_net(struct net *net)
4088 {
4089 	free_percpu(net->core.prot_inuse);
4090 }
4091 
4092 static struct pernet_operations net_inuse_ops = {
4093 	.init = sock_inuse_init_net,
4094 	.exit = sock_inuse_exit_net,
4095 };
4096 
4097 static __init int net_inuse_init(void)
4098 {
4099 	if (register_pernet_subsys(&net_inuse_ops))
4100 		panic("Cannot initialize net inuse counters");
4101 
4102 	return 0;
4103 }
4104 
4105 core_initcall(net_inuse_init);
4106 
4107 static int assign_proto_idx(struct proto *prot)
4108 {
4109 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4110 
4111 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4112 		pr_err("PROTO_INUSE_NR exhausted\n");
4113 		return -ENOSPC;
4114 	}
4115 
4116 	set_bit(prot->inuse_idx, proto_inuse_idx);
4117 	return 0;
4118 }
4119 
4120 static void release_proto_idx(struct proto *prot)
4121 {
4122 	if (prot->inuse_idx != PROTO_INUSE_NR)
4123 		clear_bit(prot->inuse_idx, proto_inuse_idx);
4124 }
4125 #else
4126 static inline int assign_proto_idx(struct proto *prot)
4127 {
4128 	return 0;
4129 }
4130 
4131 static inline void release_proto_idx(struct proto *prot)
4132 {
4133 }
4134 
4135 #endif
4136 
4137 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4138 {
4139 	if (!twsk_prot)
4140 		return;
4141 	kfree(twsk_prot->twsk_slab_name);
4142 	twsk_prot->twsk_slab_name = NULL;
4143 	kmem_cache_destroy(twsk_prot->twsk_slab);
4144 	twsk_prot->twsk_slab = NULL;
4145 }
4146 
4147 static int tw_prot_init(const struct proto *prot)
4148 {
4149 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4150 
4151 	if (!twsk_prot)
4152 		return 0;
4153 
4154 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4155 					      prot->name);
4156 	if (!twsk_prot->twsk_slab_name)
4157 		return -ENOMEM;
4158 
4159 	twsk_prot->twsk_slab =
4160 		kmem_cache_create(twsk_prot->twsk_slab_name,
4161 				  twsk_prot->twsk_obj_size, 0,
4162 				  SLAB_ACCOUNT | prot->slab_flags,
4163 				  NULL);
4164 	if (!twsk_prot->twsk_slab) {
4165 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4166 			prot->name);
4167 		return -ENOMEM;
4168 	}
4169 
4170 	return 0;
4171 }
4172 
4173 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4174 {
4175 	if (!rsk_prot)
4176 		return;
4177 	kfree(rsk_prot->slab_name);
4178 	rsk_prot->slab_name = NULL;
4179 	kmem_cache_destroy(rsk_prot->slab);
4180 	rsk_prot->slab = NULL;
4181 }
4182 
4183 static int req_prot_init(const struct proto *prot)
4184 {
4185 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
4186 
4187 	if (!rsk_prot)
4188 		return 0;
4189 
4190 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4191 					prot->name);
4192 	if (!rsk_prot->slab_name)
4193 		return -ENOMEM;
4194 
4195 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4196 					   rsk_prot->obj_size, 0,
4197 					   SLAB_ACCOUNT | prot->slab_flags,
4198 					   NULL);
4199 
4200 	if (!rsk_prot->slab) {
4201 		pr_crit("%s: Can't create request sock SLAB cache!\n",
4202 			prot->name);
4203 		return -ENOMEM;
4204 	}
4205 	return 0;
4206 }
4207 
4208 int proto_register(struct proto *prot, int alloc_slab)
4209 {
4210 	int ret = -ENOBUFS;
4211 
4212 	if (prot->memory_allocated && !prot->sysctl_mem) {
4213 		pr_err("%s: missing sysctl_mem\n", prot->name);
4214 		return -EINVAL;
4215 	}
4216 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4217 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4218 		return -EINVAL;
4219 	}
4220 	if (alloc_slab) {
4221 		struct kmem_cache_args args = {
4222 			.useroffset	= prot->useroffset,
4223 			.usersize	= prot->usersize,
4224 			.freeptr_offset = prot->freeptr_offset,
4225 			.use_freeptr_offset = !!prot->freeptr_offset,
4226 		};
4227 
4228 		prot->slab = kmem_cache_create(prot->name, prot->obj_size,
4229 					&args,
4230 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4231 					prot->slab_flags);
4232 		if (prot->slab == NULL) {
4233 			pr_crit("%s: Can't create sock SLAB cache!\n",
4234 				prot->name);
4235 			goto out;
4236 		}
4237 
4238 		if (req_prot_init(prot))
4239 			goto out_free_request_sock_slab;
4240 
4241 		if (tw_prot_init(prot))
4242 			goto out_free_timewait_sock_slab;
4243 	}
4244 
4245 	mutex_lock(&proto_list_mutex);
4246 	ret = assign_proto_idx(prot);
4247 	if (ret) {
4248 		mutex_unlock(&proto_list_mutex);
4249 		goto out_free_timewait_sock_slab;
4250 	}
4251 	list_add(&prot->node, &proto_list);
4252 	mutex_unlock(&proto_list_mutex);
4253 	return ret;
4254 
4255 out_free_timewait_sock_slab:
4256 	if (alloc_slab)
4257 		tw_prot_cleanup(prot->twsk_prot);
4258 out_free_request_sock_slab:
4259 	if (alloc_slab) {
4260 		req_prot_cleanup(prot->rsk_prot);
4261 
4262 		kmem_cache_destroy(prot->slab);
4263 		prot->slab = NULL;
4264 	}
4265 out:
4266 	return ret;
4267 }
4268 EXPORT_SYMBOL(proto_register);
4269 
4270 void proto_unregister(struct proto *prot)
4271 {
4272 	mutex_lock(&proto_list_mutex);
4273 	release_proto_idx(prot);
4274 	list_del(&prot->node);
4275 	mutex_unlock(&proto_list_mutex);
4276 
4277 	kmem_cache_destroy(prot->slab);
4278 	prot->slab = NULL;
4279 
4280 	req_prot_cleanup(prot->rsk_prot);
4281 	tw_prot_cleanup(prot->twsk_prot);
4282 }
4283 EXPORT_SYMBOL(proto_unregister);
4284 
4285 int sock_load_diag_module(int family, int protocol)
4286 {
4287 	if (!protocol) {
4288 		if (!sock_is_registered(family))
4289 			return -ENOENT;
4290 
4291 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4292 				      NETLINK_SOCK_DIAG, family);
4293 	}
4294 
4295 #ifdef CONFIG_INET
4296 	if (family == AF_INET &&
4297 	    protocol != IPPROTO_RAW &&
4298 	    protocol < MAX_INET_PROTOS &&
4299 	    !rcu_access_pointer(inet_protos[protocol]))
4300 		return -ENOENT;
4301 #endif
4302 
4303 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4304 			      NETLINK_SOCK_DIAG, family, protocol);
4305 }
4306 EXPORT_SYMBOL(sock_load_diag_module);
4307 
4308 #ifdef CONFIG_PROC_FS
4309 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4310 	__acquires(proto_list_mutex)
4311 {
4312 	mutex_lock(&proto_list_mutex);
4313 	return seq_list_start_head(&proto_list, *pos);
4314 }
4315 
4316 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4317 {
4318 	return seq_list_next(v, &proto_list, pos);
4319 }
4320 
4321 static void proto_seq_stop(struct seq_file *seq, void *v)
4322 	__releases(proto_list_mutex)
4323 {
4324 	mutex_unlock(&proto_list_mutex);
4325 }
4326 
4327 static char proto_method_implemented(const void *method)
4328 {
4329 	return method == NULL ? 'n' : 'y';
4330 }
4331 static long sock_prot_memory_allocated(struct proto *proto)
4332 {
4333 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4334 }
4335 
4336 static const char *sock_prot_memory_pressure(struct proto *proto)
4337 {
4338 	return proto->memory_pressure != NULL ?
4339 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4340 }
4341 
4342 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4343 {
4344 
4345 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4346 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4347 		   proto->name,
4348 		   proto->obj_size,
4349 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4350 		   sock_prot_memory_allocated(proto),
4351 		   sock_prot_memory_pressure(proto),
4352 		   proto->max_header,
4353 		   proto->slab == NULL ? "no" : "yes",
4354 		   module_name(proto->owner),
4355 		   proto_method_implemented(proto->close),
4356 		   proto_method_implemented(proto->connect),
4357 		   proto_method_implemented(proto->disconnect),
4358 		   proto_method_implemented(proto->accept),
4359 		   proto_method_implemented(proto->ioctl),
4360 		   proto_method_implemented(proto->init),
4361 		   proto_method_implemented(proto->destroy),
4362 		   proto_method_implemented(proto->shutdown),
4363 		   proto_method_implemented(proto->setsockopt),
4364 		   proto_method_implemented(proto->getsockopt),
4365 		   proto_method_implemented(proto->sendmsg),
4366 		   proto_method_implemented(proto->recvmsg),
4367 		   proto_method_implemented(proto->bind),
4368 		   proto_method_implemented(proto->backlog_rcv),
4369 		   proto_method_implemented(proto->hash),
4370 		   proto_method_implemented(proto->unhash),
4371 		   proto_method_implemented(proto->get_port),
4372 		   proto_method_implemented(proto->enter_memory_pressure));
4373 }
4374 
4375 static int proto_seq_show(struct seq_file *seq, void *v)
4376 {
4377 	if (v == &proto_list)
4378 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4379 			   "protocol",
4380 			   "size",
4381 			   "sockets",
4382 			   "memory",
4383 			   "press",
4384 			   "maxhdr",
4385 			   "slab",
4386 			   "module",
4387 			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4388 	else
4389 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4390 	return 0;
4391 }
4392 
4393 static const struct seq_operations proto_seq_ops = {
4394 	.start  = proto_seq_start,
4395 	.next   = proto_seq_next,
4396 	.stop   = proto_seq_stop,
4397 	.show   = proto_seq_show,
4398 };
4399 
4400 static __net_init int proto_init_net(struct net *net)
4401 {
4402 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4403 			sizeof(struct seq_net_private)))
4404 		return -ENOMEM;
4405 
4406 	return 0;
4407 }
4408 
4409 static __net_exit void proto_exit_net(struct net *net)
4410 {
4411 	remove_proc_entry("protocols", net->proc_net);
4412 }
4413 
4414 
4415 static __net_initdata struct pernet_operations proto_net_ops = {
4416 	.init = proto_init_net,
4417 	.exit = proto_exit_net,
4418 };
4419 
4420 static int __init proto_init(void)
4421 {
4422 	return register_pernet_subsys(&proto_net_ops);
4423 }
4424 
4425 subsys_initcall(proto_init);
4426 
4427 #endif /* PROC_FS */
4428 
4429 #ifdef CONFIG_NET_RX_BUSY_POLL
4430 bool sk_busy_loop_end(void *p, unsigned long start_time)
4431 {
4432 	struct sock *sk = p;
4433 
4434 	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4435 		return true;
4436 
4437 	if (sk_is_udp(sk) &&
4438 	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4439 		return true;
4440 
4441 	return sk_busy_loop_timeout(sk, start_time);
4442 }
4443 EXPORT_SYMBOL(sk_busy_loop_end);
4444 #endif /* CONFIG_NET_RX_BUSY_POLL */
4445 
4446 int sock_bind_add(struct sock *sk, struct sockaddr_unsized *addr, int addr_len)
4447 {
4448 	if (!sk->sk_prot->bind_add)
4449 		return -EOPNOTSUPP;
4450 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4451 }
4452 EXPORT_SYMBOL(sock_bind_add);
4453 
4454 /* Copy 'size' bytes from userspace and return `size` back to userspace */
4455 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4456 		     void __user *arg, void *karg, size_t size)
4457 {
4458 	int ret;
4459 
4460 	if (copy_from_user(karg, arg, size))
4461 		return -EFAULT;
4462 
4463 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4464 	if (ret)
4465 		return ret;
4466 
4467 	if (copy_to_user(arg, karg, size))
4468 		return -EFAULT;
4469 
4470 	return 0;
4471 }
4472 EXPORT_SYMBOL(sock_ioctl_inout);
4473 
4474 /* This is the most common ioctl prep function, where the result (4 bytes) is
4475  * copied back to userspace if the ioctl() returns successfully. No input is
4476  * copied from userspace as input argument.
4477  */
4478 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4479 {
4480 	int ret, karg = 0;
4481 
4482 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4483 	if (ret)
4484 		return ret;
4485 
4486 	return put_user(karg, (int __user *)arg);
4487 }
4488 
4489 /* A wrapper around sock ioctls, which copies the data from userspace
4490  * (depending on the protocol/ioctl), and copies back the result to userspace.
4491  * The main motivation for this function is to pass kernel memory to the
4492  * protocol ioctl callbacks, instead of userspace memory.
4493  */
4494 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4495 {
4496 	int rc = 1;
4497 
4498 	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4499 		rc = ipmr_sk_ioctl(sk, cmd, arg);
4500 	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4501 		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4502 	else if (sk_is_phonet(sk))
4503 		rc = phonet_sk_ioctl(sk, cmd, arg);
4504 
4505 	/* If ioctl was processed, returns its value */
4506 	if (rc <= 0)
4507 		return rc;
4508 
4509 	/* Otherwise call the default handler */
4510 	return sock_ioctl_out(sk, cmd, arg);
4511 }
4512 EXPORT_SYMBOL(sk_ioctl);
4513 
4514 static int __init sock_struct_check(void)
4515 {
4516 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4517 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4518 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4519 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4520 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4521 
4522 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4523 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4524 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4525 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4526 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4527 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4528 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4529 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4530 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4531 
4532 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4533 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4534 #ifdef CONFIG_MEMCG
4535 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4536 #endif
4537 
4538 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4539 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4540 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4541 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4542 
4543 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4544 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4545 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_err_soft);
4546 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4547 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4548 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4549 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4550 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4551 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4552 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4553 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4554 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4555 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4556 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4557 
4558 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_pending_confirm);
4559 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_status);
4560 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4561 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4562 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4563 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4564 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_uid);
4565 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_protocol);
4566 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4567 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4568 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4569 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4570 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4571 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4572 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndbuf);
4573 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4574 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4575 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4576 	return 0;
4577 }
4578 
4579 core_initcall(sock_struct_check);
4580