xref: /linux/net/core/sock.c (revision e80a48bade619ec5a92230b3d4ae84bfc2746822)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <asm/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/init.h>
111 #include <linux/highmem.h>
112 #include <linux/user_namespace.h>
113 #include <linux/static_key.h>
114 #include <linux/memcontrol.h>
115 #include <linux/prefetch.h>
116 #include <linux/compat.h>
117 
118 #include <linux/uaccess.h>
119 
120 #include <linux/netdevice.h>
121 #include <net/protocol.h>
122 #include <linux/skbuff.h>
123 #include <net/net_namespace.h>
124 #include <net/request_sock.h>
125 #include <net/sock.h>
126 #include <linux/net_tstamp.h>
127 #include <net/xfrm.h>
128 #include <linux/ipsec.h>
129 #include <net/cls_cgroup.h>
130 #include <net/netprio_cgroup.h>
131 #include <linux/sock_diag.h>
132 
133 #include <linux/filter.h>
134 #include <net/sock_reuseport.h>
135 #include <net/bpf_sk_storage.h>
136 
137 #include <trace/events/sock.h>
138 
139 #include <net/tcp.h>
140 #include <net/busy_poll.h>
141 
142 #include <linux/ethtool.h>
143 
144 #include "dev.h"
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_def_write_space_wfree(struct sock *sk);
150 static void sock_def_write_space(struct sock *sk);
151 
152 /**
153  * sk_ns_capable - General socket capability test
154  * @sk: Socket to use a capability on or through
155  * @user_ns: The user namespace of the capability to use
156  * @cap: The capability to use
157  *
158  * Test to see if the opener of the socket had when the socket was
159  * created and the current process has the capability @cap in the user
160  * namespace @user_ns.
161  */
162 bool sk_ns_capable(const struct sock *sk,
163 		   struct user_namespace *user_ns, int cap)
164 {
165 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
166 		ns_capable(user_ns, cap);
167 }
168 EXPORT_SYMBOL(sk_ns_capable);
169 
170 /**
171  * sk_capable - Socket global capability test
172  * @sk: Socket to use a capability on or through
173  * @cap: The global capability to use
174  *
175  * Test to see if the opener of the socket had when the socket was
176  * created and the current process has the capability @cap in all user
177  * namespaces.
178  */
179 bool sk_capable(const struct sock *sk, int cap)
180 {
181 	return sk_ns_capable(sk, &init_user_ns, cap);
182 }
183 EXPORT_SYMBOL(sk_capable);
184 
185 /**
186  * sk_net_capable - Network namespace socket capability test
187  * @sk: Socket to use a capability on or through
188  * @cap: The capability to use
189  *
190  * Test to see if the opener of the socket had when the socket was created
191  * and the current process has the capability @cap over the network namespace
192  * the socket is a member of.
193  */
194 bool sk_net_capable(const struct sock *sk, int cap)
195 {
196 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
197 }
198 EXPORT_SYMBOL(sk_net_capable);
199 
200 /*
201  * Each address family might have different locking rules, so we have
202  * one slock key per address family and separate keys for internal and
203  * userspace sockets.
204  */
205 static struct lock_class_key af_family_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_keys[AF_MAX];
207 static struct lock_class_key af_family_slock_keys[AF_MAX];
208 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
209 
210 /*
211  * Make lock validator output more readable. (we pre-construct these
212  * strings build-time, so that runtime initialization of socket
213  * locks is fast):
214  */
215 
216 #define _sock_locks(x)						  \
217   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
218   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
219   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
220   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
221   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
222   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
223   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
224   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
225   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
226   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
227   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
228   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
229   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
230   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
231   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
232   x "AF_MCTP"  , \
233   x "AF_MAX"
234 
235 static const char *const af_family_key_strings[AF_MAX+1] = {
236 	_sock_locks("sk_lock-")
237 };
238 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
239 	_sock_locks("slock-")
240 };
241 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
242 	_sock_locks("clock-")
243 };
244 
245 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
246 	_sock_locks("k-sk_lock-")
247 };
248 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
249 	_sock_locks("k-slock-")
250 };
251 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
252 	_sock_locks("k-clock-")
253 };
254 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
255 	_sock_locks("rlock-")
256 };
257 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
258 	_sock_locks("wlock-")
259 };
260 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
261 	_sock_locks("elock-")
262 };
263 
264 /*
265  * sk_callback_lock and sk queues locking rules are per-address-family,
266  * so split the lock classes by using a per-AF key:
267  */
268 static struct lock_class_key af_callback_keys[AF_MAX];
269 static struct lock_class_key af_rlock_keys[AF_MAX];
270 static struct lock_class_key af_wlock_keys[AF_MAX];
271 static struct lock_class_key af_elock_keys[AF_MAX];
272 static struct lock_class_key af_kern_callback_keys[AF_MAX];
273 
274 /* Run time adjustable parameters. */
275 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
276 EXPORT_SYMBOL(sysctl_wmem_max);
277 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
278 EXPORT_SYMBOL(sysctl_rmem_max);
279 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
280 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
281 
282 /* Maximal space eaten by iovec or ancillary data plus some space */
283 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
284 EXPORT_SYMBOL(sysctl_optmem_max);
285 
286 int sysctl_tstamp_allow_data __read_mostly = 1;
287 
288 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
289 EXPORT_SYMBOL_GPL(memalloc_socks_key);
290 
291 /**
292  * sk_set_memalloc - sets %SOCK_MEMALLOC
293  * @sk: socket to set it on
294  *
295  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
296  * It's the responsibility of the admin to adjust min_free_kbytes
297  * to meet the requirements
298  */
299 void sk_set_memalloc(struct sock *sk)
300 {
301 	sock_set_flag(sk, SOCK_MEMALLOC);
302 	sk->sk_allocation |= __GFP_MEMALLOC;
303 	static_branch_inc(&memalloc_socks_key);
304 }
305 EXPORT_SYMBOL_GPL(sk_set_memalloc);
306 
307 void sk_clear_memalloc(struct sock *sk)
308 {
309 	sock_reset_flag(sk, SOCK_MEMALLOC);
310 	sk->sk_allocation &= ~__GFP_MEMALLOC;
311 	static_branch_dec(&memalloc_socks_key);
312 
313 	/*
314 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
315 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
316 	 * it has rmem allocations due to the last swapfile being deactivated
317 	 * but there is a risk that the socket is unusable due to exceeding
318 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
319 	 */
320 	sk_mem_reclaim(sk);
321 }
322 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
323 
324 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
325 {
326 	int ret;
327 	unsigned int noreclaim_flag;
328 
329 	/* these should have been dropped before queueing */
330 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
331 
332 	noreclaim_flag = memalloc_noreclaim_save();
333 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
334 				 tcp_v6_do_rcv,
335 				 tcp_v4_do_rcv,
336 				 sk, skb);
337 	memalloc_noreclaim_restore(noreclaim_flag);
338 
339 	return ret;
340 }
341 EXPORT_SYMBOL(__sk_backlog_rcv);
342 
343 void sk_error_report(struct sock *sk)
344 {
345 	sk->sk_error_report(sk);
346 
347 	switch (sk->sk_family) {
348 	case AF_INET:
349 		fallthrough;
350 	case AF_INET6:
351 		trace_inet_sk_error_report(sk);
352 		break;
353 	default:
354 		break;
355 	}
356 }
357 EXPORT_SYMBOL(sk_error_report);
358 
359 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
360 {
361 	struct __kernel_sock_timeval tv;
362 
363 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
364 		tv.tv_sec = 0;
365 		tv.tv_usec = 0;
366 	} else {
367 		tv.tv_sec = timeo / HZ;
368 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
369 	}
370 
371 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
372 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
373 		*(struct old_timeval32 *)optval = tv32;
374 		return sizeof(tv32);
375 	}
376 
377 	if (old_timeval) {
378 		struct __kernel_old_timeval old_tv;
379 		old_tv.tv_sec = tv.tv_sec;
380 		old_tv.tv_usec = tv.tv_usec;
381 		*(struct __kernel_old_timeval *)optval = old_tv;
382 		return sizeof(old_tv);
383 	}
384 
385 	*(struct __kernel_sock_timeval *)optval = tv;
386 	return sizeof(tv);
387 }
388 EXPORT_SYMBOL(sock_get_timeout);
389 
390 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
391 			   sockptr_t optval, int optlen, bool old_timeval)
392 {
393 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
394 		struct old_timeval32 tv32;
395 
396 		if (optlen < sizeof(tv32))
397 			return -EINVAL;
398 
399 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
400 			return -EFAULT;
401 		tv->tv_sec = tv32.tv_sec;
402 		tv->tv_usec = tv32.tv_usec;
403 	} else if (old_timeval) {
404 		struct __kernel_old_timeval old_tv;
405 
406 		if (optlen < sizeof(old_tv))
407 			return -EINVAL;
408 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
409 			return -EFAULT;
410 		tv->tv_sec = old_tv.tv_sec;
411 		tv->tv_usec = old_tv.tv_usec;
412 	} else {
413 		if (optlen < sizeof(*tv))
414 			return -EINVAL;
415 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
416 			return -EFAULT;
417 	}
418 
419 	return 0;
420 }
421 EXPORT_SYMBOL(sock_copy_user_timeval);
422 
423 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
424 			    bool old_timeval)
425 {
426 	struct __kernel_sock_timeval tv;
427 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
428 
429 	if (err)
430 		return err;
431 
432 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
433 		return -EDOM;
434 
435 	if (tv.tv_sec < 0) {
436 		static int warned __read_mostly;
437 
438 		*timeo_p = 0;
439 		if (warned < 10 && net_ratelimit()) {
440 			warned++;
441 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
442 				__func__, current->comm, task_pid_nr(current));
443 		}
444 		return 0;
445 	}
446 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
447 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
448 		return 0;
449 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
450 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
451 	return 0;
452 }
453 
454 static bool sock_needs_netstamp(const struct sock *sk)
455 {
456 	switch (sk->sk_family) {
457 	case AF_UNSPEC:
458 	case AF_UNIX:
459 		return false;
460 	default:
461 		return true;
462 	}
463 }
464 
465 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
466 {
467 	if (sk->sk_flags & flags) {
468 		sk->sk_flags &= ~flags;
469 		if (sock_needs_netstamp(sk) &&
470 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
471 			net_disable_timestamp();
472 	}
473 }
474 
475 
476 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 {
478 	unsigned long flags;
479 	struct sk_buff_head *list = &sk->sk_receive_queue;
480 
481 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
482 		atomic_inc(&sk->sk_drops);
483 		trace_sock_rcvqueue_full(sk, skb);
484 		return -ENOMEM;
485 	}
486 
487 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
488 		atomic_inc(&sk->sk_drops);
489 		return -ENOBUFS;
490 	}
491 
492 	skb->dev = NULL;
493 	skb_set_owner_r(skb, sk);
494 
495 	/* we escape from rcu protected region, make sure we dont leak
496 	 * a norefcounted dst
497 	 */
498 	skb_dst_force(skb);
499 
500 	spin_lock_irqsave(&list->lock, flags);
501 	sock_skb_set_dropcount(sk, skb);
502 	__skb_queue_tail(list, skb);
503 	spin_unlock_irqrestore(&list->lock, flags);
504 
505 	if (!sock_flag(sk, SOCK_DEAD))
506 		sk->sk_data_ready(sk);
507 	return 0;
508 }
509 EXPORT_SYMBOL(__sock_queue_rcv_skb);
510 
511 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
512 			      enum skb_drop_reason *reason)
513 {
514 	enum skb_drop_reason drop_reason;
515 	int err;
516 
517 	err = sk_filter(sk, skb);
518 	if (err) {
519 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
520 		goto out;
521 	}
522 	err = __sock_queue_rcv_skb(sk, skb);
523 	switch (err) {
524 	case -ENOMEM:
525 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
526 		break;
527 	case -ENOBUFS:
528 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
529 		break;
530 	default:
531 		drop_reason = SKB_NOT_DROPPED_YET;
532 		break;
533 	}
534 out:
535 	if (reason)
536 		*reason = drop_reason;
537 	return err;
538 }
539 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
540 
541 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
542 		     const int nested, unsigned int trim_cap, bool refcounted)
543 {
544 	int rc = NET_RX_SUCCESS;
545 
546 	if (sk_filter_trim_cap(sk, skb, trim_cap))
547 		goto discard_and_relse;
548 
549 	skb->dev = NULL;
550 
551 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
552 		atomic_inc(&sk->sk_drops);
553 		goto discard_and_relse;
554 	}
555 	if (nested)
556 		bh_lock_sock_nested(sk);
557 	else
558 		bh_lock_sock(sk);
559 	if (!sock_owned_by_user(sk)) {
560 		/*
561 		 * trylock + unlock semantics:
562 		 */
563 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
564 
565 		rc = sk_backlog_rcv(sk, skb);
566 
567 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
568 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
569 		bh_unlock_sock(sk);
570 		atomic_inc(&sk->sk_drops);
571 		goto discard_and_relse;
572 	}
573 
574 	bh_unlock_sock(sk);
575 out:
576 	if (refcounted)
577 		sock_put(sk);
578 	return rc;
579 discard_and_relse:
580 	kfree_skb(skb);
581 	goto out;
582 }
583 EXPORT_SYMBOL(__sk_receive_skb);
584 
585 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
586 							  u32));
587 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
588 							   u32));
589 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
590 {
591 	struct dst_entry *dst = __sk_dst_get(sk);
592 
593 	if (dst && dst->obsolete &&
594 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
595 			       dst, cookie) == NULL) {
596 		sk_tx_queue_clear(sk);
597 		sk->sk_dst_pending_confirm = 0;
598 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
599 		dst_release(dst);
600 		return NULL;
601 	}
602 
603 	return dst;
604 }
605 EXPORT_SYMBOL(__sk_dst_check);
606 
607 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 	struct dst_entry *dst = sk_dst_get(sk);
610 
611 	if (dst && dst->obsolete &&
612 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 			       dst, cookie) == NULL) {
614 		sk_dst_reset(sk);
615 		dst_release(dst);
616 		return NULL;
617 	}
618 
619 	return dst;
620 }
621 EXPORT_SYMBOL(sk_dst_check);
622 
623 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
624 {
625 	int ret = -ENOPROTOOPT;
626 #ifdef CONFIG_NETDEVICES
627 	struct net *net = sock_net(sk);
628 
629 	/* Sorry... */
630 	ret = -EPERM;
631 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
632 		goto out;
633 
634 	ret = -EINVAL;
635 	if (ifindex < 0)
636 		goto out;
637 
638 	/* Paired with all READ_ONCE() done locklessly. */
639 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
640 
641 	if (sk->sk_prot->rehash)
642 		sk->sk_prot->rehash(sk);
643 	sk_dst_reset(sk);
644 
645 	ret = 0;
646 
647 out:
648 #endif
649 
650 	return ret;
651 }
652 
653 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
654 {
655 	int ret;
656 
657 	if (lock_sk)
658 		lock_sock(sk);
659 	ret = sock_bindtoindex_locked(sk, ifindex);
660 	if (lock_sk)
661 		release_sock(sk);
662 
663 	return ret;
664 }
665 EXPORT_SYMBOL(sock_bindtoindex);
666 
667 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
668 {
669 	int ret = -ENOPROTOOPT;
670 #ifdef CONFIG_NETDEVICES
671 	struct net *net = sock_net(sk);
672 	char devname[IFNAMSIZ];
673 	int index;
674 
675 	ret = -EINVAL;
676 	if (optlen < 0)
677 		goto out;
678 
679 	/* Bind this socket to a particular device like "eth0",
680 	 * as specified in the passed interface name. If the
681 	 * name is "" or the option length is zero the socket
682 	 * is not bound.
683 	 */
684 	if (optlen > IFNAMSIZ - 1)
685 		optlen = IFNAMSIZ - 1;
686 	memset(devname, 0, sizeof(devname));
687 
688 	ret = -EFAULT;
689 	if (copy_from_sockptr(devname, optval, optlen))
690 		goto out;
691 
692 	index = 0;
693 	if (devname[0] != '\0') {
694 		struct net_device *dev;
695 
696 		rcu_read_lock();
697 		dev = dev_get_by_name_rcu(net, devname);
698 		if (dev)
699 			index = dev->ifindex;
700 		rcu_read_unlock();
701 		ret = -ENODEV;
702 		if (!dev)
703 			goto out;
704 	}
705 
706 	sockopt_lock_sock(sk);
707 	ret = sock_bindtoindex_locked(sk, index);
708 	sockopt_release_sock(sk);
709 out:
710 #endif
711 
712 	return ret;
713 }
714 
715 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
716 				sockptr_t optlen, int len)
717 {
718 	int ret = -ENOPROTOOPT;
719 #ifdef CONFIG_NETDEVICES
720 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
721 	struct net *net = sock_net(sk);
722 	char devname[IFNAMSIZ];
723 
724 	if (bound_dev_if == 0) {
725 		len = 0;
726 		goto zero;
727 	}
728 
729 	ret = -EINVAL;
730 	if (len < IFNAMSIZ)
731 		goto out;
732 
733 	ret = netdev_get_name(net, devname, bound_dev_if);
734 	if (ret)
735 		goto out;
736 
737 	len = strlen(devname) + 1;
738 
739 	ret = -EFAULT;
740 	if (copy_to_sockptr(optval, devname, len))
741 		goto out;
742 
743 zero:
744 	ret = -EFAULT;
745 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
746 		goto out;
747 
748 	ret = 0;
749 
750 out:
751 #endif
752 
753 	return ret;
754 }
755 
756 bool sk_mc_loop(struct sock *sk)
757 {
758 	if (dev_recursion_level())
759 		return false;
760 	if (!sk)
761 		return true;
762 	switch (sk->sk_family) {
763 	case AF_INET:
764 		return inet_sk(sk)->mc_loop;
765 #if IS_ENABLED(CONFIG_IPV6)
766 	case AF_INET6:
767 		return inet6_sk(sk)->mc_loop;
768 #endif
769 	}
770 	WARN_ON_ONCE(1);
771 	return true;
772 }
773 EXPORT_SYMBOL(sk_mc_loop);
774 
775 void sock_set_reuseaddr(struct sock *sk)
776 {
777 	lock_sock(sk);
778 	sk->sk_reuse = SK_CAN_REUSE;
779 	release_sock(sk);
780 }
781 EXPORT_SYMBOL(sock_set_reuseaddr);
782 
783 void sock_set_reuseport(struct sock *sk)
784 {
785 	lock_sock(sk);
786 	sk->sk_reuseport = true;
787 	release_sock(sk);
788 }
789 EXPORT_SYMBOL(sock_set_reuseport);
790 
791 void sock_no_linger(struct sock *sk)
792 {
793 	lock_sock(sk);
794 	sk->sk_lingertime = 0;
795 	sock_set_flag(sk, SOCK_LINGER);
796 	release_sock(sk);
797 }
798 EXPORT_SYMBOL(sock_no_linger);
799 
800 void sock_set_priority(struct sock *sk, u32 priority)
801 {
802 	lock_sock(sk);
803 	sk->sk_priority = priority;
804 	release_sock(sk);
805 }
806 EXPORT_SYMBOL(sock_set_priority);
807 
808 void sock_set_sndtimeo(struct sock *sk, s64 secs)
809 {
810 	lock_sock(sk);
811 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
812 		sk->sk_sndtimeo = secs * HZ;
813 	else
814 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
815 	release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_set_sndtimeo);
818 
819 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
820 {
821 	if (val)  {
822 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
823 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
824 		sock_set_flag(sk, SOCK_RCVTSTAMP);
825 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
826 	} else {
827 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
828 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
829 	}
830 }
831 
832 void sock_enable_timestamps(struct sock *sk)
833 {
834 	lock_sock(sk);
835 	__sock_set_timestamps(sk, true, false, true);
836 	release_sock(sk);
837 }
838 EXPORT_SYMBOL(sock_enable_timestamps);
839 
840 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
841 {
842 	switch (optname) {
843 	case SO_TIMESTAMP_OLD:
844 		__sock_set_timestamps(sk, valbool, false, false);
845 		break;
846 	case SO_TIMESTAMP_NEW:
847 		__sock_set_timestamps(sk, valbool, true, false);
848 		break;
849 	case SO_TIMESTAMPNS_OLD:
850 		__sock_set_timestamps(sk, valbool, false, true);
851 		break;
852 	case SO_TIMESTAMPNS_NEW:
853 		__sock_set_timestamps(sk, valbool, true, true);
854 		break;
855 	}
856 }
857 
858 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
859 {
860 	struct net *net = sock_net(sk);
861 	struct net_device *dev = NULL;
862 	bool match = false;
863 	int *vclock_index;
864 	int i, num;
865 
866 	if (sk->sk_bound_dev_if)
867 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
868 
869 	if (!dev) {
870 		pr_err("%s: sock not bind to device\n", __func__);
871 		return -EOPNOTSUPP;
872 	}
873 
874 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
875 	dev_put(dev);
876 
877 	for (i = 0; i < num; i++) {
878 		if (*(vclock_index + i) == phc_index) {
879 			match = true;
880 			break;
881 		}
882 	}
883 
884 	if (num > 0)
885 		kfree(vclock_index);
886 
887 	if (!match)
888 		return -EINVAL;
889 
890 	sk->sk_bind_phc = phc_index;
891 
892 	return 0;
893 }
894 
895 int sock_set_timestamping(struct sock *sk, int optname,
896 			  struct so_timestamping timestamping)
897 {
898 	int val = timestamping.flags;
899 	int ret;
900 
901 	if (val & ~SOF_TIMESTAMPING_MASK)
902 		return -EINVAL;
903 
904 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
905 	    !(val & SOF_TIMESTAMPING_OPT_ID))
906 		return -EINVAL;
907 
908 	if (val & SOF_TIMESTAMPING_OPT_ID &&
909 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
910 		if (sk_is_tcp(sk)) {
911 			if ((1 << sk->sk_state) &
912 			    (TCPF_CLOSE | TCPF_LISTEN))
913 				return -EINVAL;
914 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
915 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
916 			else
917 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
918 		} else {
919 			atomic_set(&sk->sk_tskey, 0);
920 		}
921 	}
922 
923 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
924 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
925 		return -EINVAL;
926 
927 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
928 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
929 		if (ret)
930 			return ret;
931 	}
932 
933 	sk->sk_tsflags = val;
934 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
935 
936 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
937 		sock_enable_timestamp(sk,
938 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
939 	else
940 		sock_disable_timestamp(sk,
941 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
942 	return 0;
943 }
944 
945 void sock_set_keepalive(struct sock *sk)
946 {
947 	lock_sock(sk);
948 	if (sk->sk_prot->keepalive)
949 		sk->sk_prot->keepalive(sk, true);
950 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
951 	release_sock(sk);
952 }
953 EXPORT_SYMBOL(sock_set_keepalive);
954 
955 static void __sock_set_rcvbuf(struct sock *sk, int val)
956 {
957 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
958 	 * as a negative value.
959 	 */
960 	val = min_t(int, val, INT_MAX / 2);
961 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
962 
963 	/* We double it on the way in to account for "struct sk_buff" etc.
964 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
965 	 * will allow that much actual data to be received on that socket.
966 	 *
967 	 * Applications are unaware that "struct sk_buff" and other overheads
968 	 * allocate from the receive buffer during socket buffer allocation.
969 	 *
970 	 * And after considering the possible alternatives, returning the value
971 	 * we actually used in getsockopt is the most desirable behavior.
972 	 */
973 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
974 }
975 
976 void sock_set_rcvbuf(struct sock *sk, int val)
977 {
978 	lock_sock(sk);
979 	__sock_set_rcvbuf(sk, val);
980 	release_sock(sk);
981 }
982 EXPORT_SYMBOL(sock_set_rcvbuf);
983 
984 static void __sock_set_mark(struct sock *sk, u32 val)
985 {
986 	if (val != sk->sk_mark) {
987 		sk->sk_mark = val;
988 		sk_dst_reset(sk);
989 	}
990 }
991 
992 void sock_set_mark(struct sock *sk, u32 val)
993 {
994 	lock_sock(sk);
995 	__sock_set_mark(sk, val);
996 	release_sock(sk);
997 }
998 EXPORT_SYMBOL(sock_set_mark);
999 
1000 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1001 {
1002 	/* Round down bytes to multiple of pages */
1003 	bytes = round_down(bytes, PAGE_SIZE);
1004 
1005 	WARN_ON(bytes > sk->sk_reserved_mem);
1006 	sk->sk_reserved_mem -= bytes;
1007 	sk_mem_reclaim(sk);
1008 }
1009 
1010 static int sock_reserve_memory(struct sock *sk, int bytes)
1011 {
1012 	long allocated;
1013 	bool charged;
1014 	int pages;
1015 
1016 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1017 		return -EOPNOTSUPP;
1018 
1019 	if (!bytes)
1020 		return 0;
1021 
1022 	pages = sk_mem_pages(bytes);
1023 
1024 	/* pre-charge to memcg */
1025 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1026 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1027 	if (!charged)
1028 		return -ENOMEM;
1029 
1030 	/* pre-charge to forward_alloc */
1031 	sk_memory_allocated_add(sk, pages);
1032 	allocated = sk_memory_allocated(sk);
1033 	/* If the system goes into memory pressure with this
1034 	 * precharge, give up and return error.
1035 	 */
1036 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1037 		sk_memory_allocated_sub(sk, pages);
1038 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1039 		return -ENOMEM;
1040 	}
1041 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1042 
1043 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1044 
1045 	return 0;
1046 }
1047 
1048 void sockopt_lock_sock(struct sock *sk)
1049 {
1050 	/* When current->bpf_ctx is set, the setsockopt is called from
1051 	 * a bpf prog.  bpf has ensured the sk lock has been
1052 	 * acquired before calling setsockopt().
1053 	 */
1054 	if (has_current_bpf_ctx())
1055 		return;
1056 
1057 	lock_sock(sk);
1058 }
1059 EXPORT_SYMBOL(sockopt_lock_sock);
1060 
1061 void sockopt_release_sock(struct sock *sk)
1062 {
1063 	if (has_current_bpf_ctx())
1064 		return;
1065 
1066 	release_sock(sk);
1067 }
1068 EXPORT_SYMBOL(sockopt_release_sock);
1069 
1070 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1071 {
1072 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1073 }
1074 EXPORT_SYMBOL(sockopt_ns_capable);
1075 
1076 bool sockopt_capable(int cap)
1077 {
1078 	return has_current_bpf_ctx() || capable(cap);
1079 }
1080 EXPORT_SYMBOL(sockopt_capable);
1081 
1082 /*
1083  *	This is meant for all protocols to use and covers goings on
1084  *	at the socket level. Everything here is generic.
1085  */
1086 
1087 int sk_setsockopt(struct sock *sk, int level, int optname,
1088 		  sockptr_t optval, unsigned int optlen)
1089 {
1090 	struct so_timestamping timestamping;
1091 	struct socket *sock = sk->sk_socket;
1092 	struct sock_txtime sk_txtime;
1093 	int val;
1094 	int valbool;
1095 	struct linger ling;
1096 	int ret = 0;
1097 
1098 	/*
1099 	 *	Options without arguments
1100 	 */
1101 
1102 	if (optname == SO_BINDTODEVICE)
1103 		return sock_setbindtodevice(sk, optval, optlen);
1104 
1105 	if (optlen < sizeof(int))
1106 		return -EINVAL;
1107 
1108 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1109 		return -EFAULT;
1110 
1111 	valbool = val ? 1 : 0;
1112 
1113 	sockopt_lock_sock(sk);
1114 
1115 	switch (optname) {
1116 	case SO_DEBUG:
1117 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1118 			ret = -EACCES;
1119 		else
1120 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1121 		break;
1122 	case SO_REUSEADDR:
1123 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1124 		break;
1125 	case SO_REUSEPORT:
1126 		sk->sk_reuseport = valbool;
1127 		break;
1128 	case SO_TYPE:
1129 	case SO_PROTOCOL:
1130 	case SO_DOMAIN:
1131 	case SO_ERROR:
1132 		ret = -ENOPROTOOPT;
1133 		break;
1134 	case SO_DONTROUTE:
1135 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1136 		sk_dst_reset(sk);
1137 		break;
1138 	case SO_BROADCAST:
1139 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1140 		break;
1141 	case SO_SNDBUF:
1142 		/* Don't error on this BSD doesn't and if you think
1143 		 * about it this is right. Otherwise apps have to
1144 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1145 		 * are treated in BSD as hints
1146 		 */
1147 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1148 set_sndbuf:
1149 		/* Ensure val * 2 fits into an int, to prevent max_t()
1150 		 * from treating it as a negative value.
1151 		 */
1152 		val = min_t(int, val, INT_MAX / 2);
1153 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1154 		WRITE_ONCE(sk->sk_sndbuf,
1155 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1156 		/* Wake up sending tasks if we upped the value. */
1157 		sk->sk_write_space(sk);
1158 		break;
1159 
1160 	case SO_SNDBUFFORCE:
1161 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1162 			ret = -EPERM;
1163 			break;
1164 		}
1165 
1166 		/* No negative values (to prevent underflow, as val will be
1167 		 * multiplied by 2).
1168 		 */
1169 		if (val < 0)
1170 			val = 0;
1171 		goto set_sndbuf;
1172 
1173 	case SO_RCVBUF:
1174 		/* Don't error on this BSD doesn't and if you think
1175 		 * about it this is right. Otherwise apps have to
1176 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1177 		 * are treated in BSD as hints
1178 		 */
1179 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1180 		break;
1181 
1182 	case SO_RCVBUFFORCE:
1183 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1184 			ret = -EPERM;
1185 			break;
1186 		}
1187 
1188 		/* No negative values (to prevent underflow, as val will be
1189 		 * multiplied by 2).
1190 		 */
1191 		__sock_set_rcvbuf(sk, max(val, 0));
1192 		break;
1193 
1194 	case SO_KEEPALIVE:
1195 		if (sk->sk_prot->keepalive)
1196 			sk->sk_prot->keepalive(sk, valbool);
1197 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1198 		break;
1199 
1200 	case SO_OOBINLINE:
1201 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1202 		break;
1203 
1204 	case SO_NO_CHECK:
1205 		sk->sk_no_check_tx = valbool;
1206 		break;
1207 
1208 	case SO_PRIORITY:
1209 		if ((val >= 0 && val <= 6) ||
1210 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1211 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1212 			sk->sk_priority = val;
1213 		else
1214 			ret = -EPERM;
1215 		break;
1216 
1217 	case SO_LINGER:
1218 		if (optlen < sizeof(ling)) {
1219 			ret = -EINVAL;	/* 1003.1g */
1220 			break;
1221 		}
1222 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1223 			ret = -EFAULT;
1224 			break;
1225 		}
1226 		if (!ling.l_onoff)
1227 			sock_reset_flag(sk, SOCK_LINGER);
1228 		else {
1229 #if (BITS_PER_LONG == 32)
1230 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1231 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1232 			else
1233 #endif
1234 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1235 			sock_set_flag(sk, SOCK_LINGER);
1236 		}
1237 		break;
1238 
1239 	case SO_BSDCOMPAT:
1240 		break;
1241 
1242 	case SO_PASSCRED:
1243 		if (valbool)
1244 			set_bit(SOCK_PASSCRED, &sock->flags);
1245 		else
1246 			clear_bit(SOCK_PASSCRED, &sock->flags);
1247 		break;
1248 
1249 	case SO_TIMESTAMP_OLD:
1250 	case SO_TIMESTAMP_NEW:
1251 	case SO_TIMESTAMPNS_OLD:
1252 	case SO_TIMESTAMPNS_NEW:
1253 		sock_set_timestamp(sk, optname, valbool);
1254 		break;
1255 
1256 	case SO_TIMESTAMPING_NEW:
1257 	case SO_TIMESTAMPING_OLD:
1258 		if (optlen == sizeof(timestamping)) {
1259 			if (copy_from_sockptr(&timestamping, optval,
1260 					      sizeof(timestamping))) {
1261 				ret = -EFAULT;
1262 				break;
1263 			}
1264 		} else {
1265 			memset(&timestamping, 0, sizeof(timestamping));
1266 			timestamping.flags = val;
1267 		}
1268 		ret = sock_set_timestamping(sk, optname, timestamping);
1269 		break;
1270 
1271 	case SO_RCVLOWAT:
1272 		if (val < 0)
1273 			val = INT_MAX;
1274 		if (sock && sock->ops->set_rcvlowat)
1275 			ret = sock->ops->set_rcvlowat(sk, val);
1276 		else
1277 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1278 		break;
1279 
1280 	case SO_RCVTIMEO_OLD:
1281 	case SO_RCVTIMEO_NEW:
1282 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1283 				       optlen, optname == SO_RCVTIMEO_OLD);
1284 		break;
1285 
1286 	case SO_SNDTIMEO_OLD:
1287 	case SO_SNDTIMEO_NEW:
1288 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1289 				       optlen, optname == SO_SNDTIMEO_OLD);
1290 		break;
1291 
1292 	case SO_ATTACH_FILTER: {
1293 		struct sock_fprog fprog;
1294 
1295 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1296 		if (!ret)
1297 			ret = sk_attach_filter(&fprog, sk);
1298 		break;
1299 	}
1300 	case SO_ATTACH_BPF:
1301 		ret = -EINVAL;
1302 		if (optlen == sizeof(u32)) {
1303 			u32 ufd;
1304 
1305 			ret = -EFAULT;
1306 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1307 				break;
1308 
1309 			ret = sk_attach_bpf(ufd, sk);
1310 		}
1311 		break;
1312 
1313 	case SO_ATTACH_REUSEPORT_CBPF: {
1314 		struct sock_fprog fprog;
1315 
1316 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1317 		if (!ret)
1318 			ret = sk_reuseport_attach_filter(&fprog, sk);
1319 		break;
1320 	}
1321 	case SO_ATTACH_REUSEPORT_EBPF:
1322 		ret = -EINVAL;
1323 		if (optlen == sizeof(u32)) {
1324 			u32 ufd;
1325 
1326 			ret = -EFAULT;
1327 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1328 				break;
1329 
1330 			ret = sk_reuseport_attach_bpf(ufd, sk);
1331 		}
1332 		break;
1333 
1334 	case SO_DETACH_REUSEPORT_BPF:
1335 		ret = reuseport_detach_prog(sk);
1336 		break;
1337 
1338 	case SO_DETACH_FILTER:
1339 		ret = sk_detach_filter(sk);
1340 		break;
1341 
1342 	case SO_LOCK_FILTER:
1343 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1344 			ret = -EPERM;
1345 		else
1346 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1347 		break;
1348 
1349 	case SO_PASSSEC:
1350 		if (valbool)
1351 			set_bit(SOCK_PASSSEC, &sock->flags);
1352 		else
1353 			clear_bit(SOCK_PASSSEC, &sock->flags);
1354 		break;
1355 	case SO_MARK:
1356 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1357 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1358 			ret = -EPERM;
1359 			break;
1360 		}
1361 
1362 		__sock_set_mark(sk, val);
1363 		break;
1364 	case SO_RCVMARK:
1365 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1366 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1367 			ret = -EPERM;
1368 			break;
1369 		}
1370 
1371 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1372 		break;
1373 
1374 	case SO_RXQ_OVFL:
1375 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1376 		break;
1377 
1378 	case SO_WIFI_STATUS:
1379 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1380 		break;
1381 
1382 	case SO_PEEK_OFF:
1383 		if (sock->ops->set_peek_off)
1384 			ret = sock->ops->set_peek_off(sk, val);
1385 		else
1386 			ret = -EOPNOTSUPP;
1387 		break;
1388 
1389 	case SO_NOFCS:
1390 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1391 		break;
1392 
1393 	case SO_SELECT_ERR_QUEUE:
1394 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1395 		break;
1396 
1397 #ifdef CONFIG_NET_RX_BUSY_POLL
1398 	case SO_BUSY_POLL:
1399 		/* allow unprivileged users to decrease the value */
1400 		if ((val > sk->sk_ll_usec) && !sockopt_capable(CAP_NET_ADMIN))
1401 			ret = -EPERM;
1402 		else {
1403 			if (val < 0)
1404 				ret = -EINVAL;
1405 			else
1406 				WRITE_ONCE(sk->sk_ll_usec, val);
1407 		}
1408 		break;
1409 	case SO_PREFER_BUSY_POLL:
1410 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1411 			ret = -EPERM;
1412 		else
1413 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1414 		break;
1415 	case SO_BUSY_POLL_BUDGET:
1416 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1417 			ret = -EPERM;
1418 		} else {
1419 			if (val < 0 || val > U16_MAX)
1420 				ret = -EINVAL;
1421 			else
1422 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1423 		}
1424 		break;
1425 #endif
1426 
1427 	case SO_MAX_PACING_RATE:
1428 		{
1429 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1430 
1431 		if (sizeof(ulval) != sizeof(val) &&
1432 		    optlen >= sizeof(ulval) &&
1433 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1434 			ret = -EFAULT;
1435 			break;
1436 		}
1437 		if (ulval != ~0UL)
1438 			cmpxchg(&sk->sk_pacing_status,
1439 				SK_PACING_NONE,
1440 				SK_PACING_NEEDED);
1441 		sk->sk_max_pacing_rate = ulval;
1442 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1443 		break;
1444 		}
1445 	case SO_INCOMING_CPU:
1446 		reuseport_update_incoming_cpu(sk, val);
1447 		break;
1448 
1449 	case SO_CNX_ADVICE:
1450 		if (val == 1)
1451 			dst_negative_advice(sk);
1452 		break;
1453 
1454 	case SO_ZEROCOPY:
1455 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1456 			if (!(sk_is_tcp(sk) ||
1457 			      (sk->sk_type == SOCK_DGRAM &&
1458 			       sk->sk_protocol == IPPROTO_UDP)))
1459 				ret = -EOPNOTSUPP;
1460 		} else if (sk->sk_family != PF_RDS) {
1461 			ret = -EOPNOTSUPP;
1462 		}
1463 		if (!ret) {
1464 			if (val < 0 || val > 1)
1465 				ret = -EINVAL;
1466 			else
1467 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1468 		}
1469 		break;
1470 
1471 	case SO_TXTIME:
1472 		if (optlen != sizeof(struct sock_txtime)) {
1473 			ret = -EINVAL;
1474 			break;
1475 		} else if (copy_from_sockptr(&sk_txtime, optval,
1476 			   sizeof(struct sock_txtime))) {
1477 			ret = -EFAULT;
1478 			break;
1479 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1480 			ret = -EINVAL;
1481 			break;
1482 		}
1483 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1484 		 * scheduler has enough safe guards.
1485 		 */
1486 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1487 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1488 			ret = -EPERM;
1489 			break;
1490 		}
1491 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1492 		sk->sk_clockid = sk_txtime.clockid;
1493 		sk->sk_txtime_deadline_mode =
1494 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1495 		sk->sk_txtime_report_errors =
1496 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1497 		break;
1498 
1499 	case SO_BINDTOIFINDEX:
1500 		ret = sock_bindtoindex_locked(sk, val);
1501 		break;
1502 
1503 	case SO_BUF_LOCK:
1504 		if (val & ~SOCK_BUF_LOCK_MASK) {
1505 			ret = -EINVAL;
1506 			break;
1507 		}
1508 		sk->sk_userlocks = val | (sk->sk_userlocks &
1509 					  ~SOCK_BUF_LOCK_MASK);
1510 		break;
1511 
1512 	case SO_RESERVE_MEM:
1513 	{
1514 		int delta;
1515 
1516 		if (val < 0) {
1517 			ret = -EINVAL;
1518 			break;
1519 		}
1520 
1521 		delta = val - sk->sk_reserved_mem;
1522 		if (delta < 0)
1523 			sock_release_reserved_memory(sk, -delta);
1524 		else
1525 			ret = sock_reserve_memory(sk, delta);
1526 		break;
1527 	}
1528 
1529 	case SO_TXREHASH:
1530 		if (val < -1 || val > 1) {
1531 			ret = -EINVAL;
1532 			break;
1533 		}
1534 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1535 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1536 		break;
1537 
1538 	default:
1539 		ret = -ENOPROTOOPT;
1540 		break;
1541 	}
1542 	sockopt_release_sock(sk);
1543 	return ret;
1544 }
1545 
1546 int sock_setsockopt(struct socket *sock, int level, int optname,
1547 		    sockptr_t optval, unsigned int optlen)
1548 {
1549 	return sk_setsockopt(sock->sk, level, optname,
1550 			     optval, optlen);
1551 }
1552 EXPORT_SYMBOL(sock_setsockopt);
1553 
1554 static const struct cred *sk_get_peer_cred(struct sock *sk)
1555 {
1556 	const struct cred *cred;
1557 
1558 	spin_lock(&sk->sk_peer_lock);
1559 	cred = get_cred(sk->sk_peer_cred);
1560 	spin_unlock(&sk->sk_peer_lock);
1561 
1562 	return cred;
1563 }
1564 
1565 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1566 			  struct ucred *ucred)
1567 {
1568 	ucred->pid = pid_vnr(pid);
1569 	ucred->uid = ucred->gid = -1;
1570 	if (cred) {
1571 		struct user_namespace *current_ns = current_user_ns();
1572 
1573 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1574 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1575 	}
1576 }
1577 
1578 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1579 {
1580 	struct user_namespace *user_ns = current_user_ns();
1581 	int i;
1582 
1583 	for (i = 0; i < src->ngroups; i++) {
1584 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1585 
1586 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1587 			return -EFAULT;
1588 	}
1589 
1590 	return 0;
1591 }
1592 
1593 int sk_getsockopt(struct sock *sk, int level, int optname,
1594 		  sockptr_t optval, sockptr_t optlen)
1595 {
1596 	struct socket *sock = sk->sk_socket;
1597 
1598 	union {
1599 		int val;
1600 		u64 val64;
1601 		unsigned long ulval;
1602 		struct linger ling;
1603 		struct old_timeval32 tm32;
1604 		struct __kernel_old_timeval tm;
1605 		struct  __kernel_sock_timeval stm;
1606 		struct sock_txtime txtime;
1607 		struct so_timestamping timestamping;
1608 	} v;
1609 
1610 	int lv = sizeof(int);
1611 	int len;
1612 
1613 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1614 		return -EFAULT;
1615 	if (len < 0)
1616 		return -EINVAL;
1617 
1618 	memset(&v, 0, sizeof(v));
1619 
1620 	switch (optname) {
1621 	case SO_DEBUG:
1622 		v.val = sock_flag(sk, SOCK_DBG);
1623 		break;
1624 
1625 	case SO_DONTROUTE:
1626 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1627 		break;
1628 
1629 	case SO_BROADCAST:
1630 		v.val = sock_flag(sk, SOCK_BROADCAST);
1631 		break;
1632 
1633 	case SO_SNDBUF:
1634 		v.val = sk->sk_sndbuf;
1635 		break;
1636 
1637 	case SO_RCVBUF:
1638 		v.val = sk->sk_rcvbuf;
1639 		break;
1640 
1641 	case SO_REUSEADDR:
1642 		v.val = sk->sk_reuse;
1643 		break;
1644 
1645 	case SO_REUSEPORT:
1646 		v.val = sk->sk_reuseport;
1647 		break;
1648 
1649 	case SO_KEEPALIVE:
1650 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1651 		break;
1652 
1653 	case SO_TYPE:
1654 		v.val = sk->sk_type;
1655 		break;
1656 
1657 	case SO_PROTOCOL:
1658 		v.val = sk->sk_protocol;
1659 		break;
1660 
1661 	case SO_DOMAIN:
1662 		v.val = sk->sk_family;
1663 		break;
1664 
1665 	case SO_ERROR:
1666 		v.val = -sock_error(sk);
1667 		if (v.val == 0)
1668 			v.val = xchg(&sk->sk_err_soft, 0);
1669 		break;
1670 
1671 	case SO_OOBINLINE:
1672 		v.val = sock_flag(sk, SOCK_URGINLINE);
1673 		break;
1674 
1675 	case SO_NO_CHECK:
1676 		v.val = sk->sk_no_check_tx;
1677 		break;
1678 
1679 	case SO_PRIORITY:
1680 		v.val = sk->sk_priority;
1681 		break;
1682 
1683 	case SO_LINGER:
1684 		lv		= sizeof(v.ling);
1685 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1686 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1687 		break;
1688 
1689 	case SO_BSDCOMPAT:
1690 		break;
1691 
1692 	case SO_TIMESTAMP_OLD:
1693 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1694 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1695 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1696 		break;
1697 
1698 	case SO_TIMESTAMPNS_OLD:
1699 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1700 		break;
1701 
1702 	case SO_TIMESTAMP_NEW:
1703 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1704 		break;
1705 
1706 	case SO_TIMESTAMPNS_NEW:
1707 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1708 		break;
1709 
1710 	case SO_TIMESTAMPING_OLD:
1711 		lv = sizeof(v.timestamping);
1712 		v.timestamping.flags = sk->sk_tsflags;
1713 		v.timestamping.bind_phc = sk->sk_bind_phc;
1714 		break;
1715 
1716 	case SO_RCVTIMEO_OLD:
1717 	case SO_RCVTIMEO_NEW:
1718 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1719 		break;
1720 
1721 	case SO_SNDTIMEO_OLD:
1722 	case SO_SNDTIMEO_NEW:
1723 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1724 		break;
1725 
1726 	case SO_RCVLOWAT:
1727 		v.val = sk->sk_rcvlowat;
1728 		break;
1729 
1730 	case SO_SNDLOWAT:
1731 		v.val = 1;
1732 		break;
1733 
1734 	case SO_PASSCRED:
1735 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1736 		break;
1737 
1738 	case SO_PEERCRED:
1739 	{
1740 		struct ucred peercred;
1741 		if (len > sizeof(peercred))
1742 			len = sizeof(peercred);
1743 
1744 		spin_lock(&sk->sk_peer_lock);
1745 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1746 		spin_unlock(&sk->sk_peer_lock);
1747 
1748 		if (copy_to_sockptr(optval, &peercred, len))
1749 			return -EFAULT;
1750 		goto lenout;
1751 	}
1752 
1753 	case SO_PEERGROUPS:
1754 	{
1755 		const struct cred *cred;
1756 		int ret, n;
1757 
1758 		cred = sk_get_peer_cred(sk);
1759 		if (!cred)
1760 			return -ENODATA;
1761 
1762 		n = cred->group_info->ngroups;
1763 		if (len < n * sizeof(gid_t)) {
1764 			len = n * sizeof(gid_t);
1765 			put_cred(cred);
1766 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1767 		}
1768 		len = n * sizeof(gid_t);
1769 
1770 		ret = groups_to_user(optval, cred->group_info);
1771 		put_cred(cred);
1772 		if (ret)
1773 			return ret;
1774 		goto lenout;
1775 	}
1776 
1777 	case SO_PEERNAME:
1778 	{
1779 		char address[128];
1780 
1781 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1782 		if (lv < 0)
1783 			return -ENOTCONN;
1784 		if (lv < len)
1785 			return -EINVAL;
1786 		if (copy_to_sockptr(optval, address, len))
1787 			return -EFAULT;
1788 		goto lenout;
1789 	}
1790 
1791 	/* Dubious BSD thing... Probably nobody even uses it, but
1792 	 * the UNIX standard wants it for whatever reason... -DaveM
1793 	 */
1794 	case SO_ACCEPTCONN:
1795 		v.val = sk->sk_state == TCP_LISTEN;
1796 		break;
1797 
1798 	case SO_PASSSEC:
1799 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1800 		break;
1801 
1802 	case SO_PEERSEC:
1803 		return security_socket_getpeersec_stream(sock,
1804 							 optval, optlen, len);
1805 
1806 	case SO_MARK:
1807 		v.val = sk->sk_mark;
1808 		break;
1809 
1810 	case SO_RCVMARK:
1811 		v.val = sock_flag(sk, SOCK_RCVMARK);
1812 		break;
1813 
1814 	case SO_RXQ_OVFL:
1815 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1816 		break;
1817 
1818 	case SO_WIFI_STATUS:
1819 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1820 		break;
1821 
1822 	case SO_PEEK_OFF:
1823 		if (!sock->ops->set_peek_off)
1824 			return -EOPNOTSUPP;
1825 
1826 		v.val = sk->sk_peek_off;
1827 		break;
1828 	case SO_NOFCS:
1829 		v.val = sock_flag(sk, SOCK_NOFCS);
1830 		break;
1831 
1832 	case SO_BINDTODEVICE:
1833 		return sock_getbindtodevice(sk, optval, optlen, len);
1834 
1835 	case SO_GET_FILTER:
1836 		len = sk_get_filter(sk, optval, len);
1837 		if (len < 0)
1838 			return len;
1839 
1840 		goto lenout;
1841 
1842 	case SO_LOCK_FILTER:
1843 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1844 		break;
1845 
1846 	case SO_BPF_EXTENSIONS:
1847 		v.val = bpf_tell_extensions();
1848 		break;
1849 
1850 	case SO_SELECT_ERR_QUEUE:
1851 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1852 		break;
1853 
1854 #ifdef CONFIG_NET_RX_BUSY_POLL
1855 	case SO_BUSY_POLL:
1856 		v.val = sk->sk_ll_usec;
1857 		break;
1858 	case SO_PREFER_BUSY_POLL:
1859 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1860 		break;
1861 #endif
1862 
1863 	case SO_MAX_PACING_RATE:
1864 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1865 			lv = sizeof(v.ulval);
1866 			v.ulval = sk->sk_max_pacing_rate;
1867 		} else {
1868 			/* 32bit version */
1869 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1870 		}
1871 		break;
1872 
1873 	case SO_INCOMING_CPU:
1874 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1875 		break;
1876 
1877 	case SO_MEMINFO:
1878 	{
1879 		u32 meminfo[SK_MEMINFO_VARS];
1880 
1881 		sk_get_meminfo(sk, meminfo);
1882 
1883 		len = min_t(unsigned int, len, sizeof(meminfo));
1884 		if (copy_to_sockptr(optval, &meminfo, len))
1885 			return -EFAULT;
1886 
1887 		goto lenout;
1888 	}
1889 
1890 #ifdef CONFIG_NET_RX_BUSY_POLL
1891 	case SO_INCOMING_NAPI_ID:
1892 		v.val = READ_ONCE(sk->sk_napi_id);
1893 
1894 		/* aggregate non-NAPI IDs down to 0 */
1895 		if (v.val < MIN_NAPI_ID)
1896 			v.val = 0;
1897 
1898 		break;
1899 #endif
1900 
1901 	case SO_COOKIE:
1902 		lv = sizeof(u64);
1903 		if (len < lv)
1904 			return -EINVAL;
1905 		v.val64 = sock_gen_cookie(sk);
1906 		break;
1907 
1908 	case SO_ZEROCOPY:
1909 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1910 		break;
1911 
1912 	case SO_TXTIME:
1913 		lv = sizeof(v.txtime);
1914 		v.txtime.clockid = sk->sk_clockid;
1915 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1916 				  SOF_TXTIME_DEADLINE_MODE : 0;
1917 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1918 				  SOF_TXTIME_REPORT_ERRORS : 0;
1919 		break;
1920 
1921 	case SO_BINDTOIFINDEX:
1922 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1923 		break;
1924 
1925 	case SO_NETNS_COOKIE:
1926 		lv = sizeof(u64);
1927 		if (len != lv)
1928 			return -EINVAL;
1929 		v.val64 = sock_net(sk)->net_cookie;
1930 		break;
1931 
1932 	case SO_BUF_LOCK:
1933 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1934 		break;
1935 
1936 	case SO_RESERVE_MEM:
1937 		v.val = sk->sk_reserved_mem;
1938 		break;
1939 
1940 	case SO_TXREHASH:
1941 		v.val = sk->sk_txrehash;
1942 		break;
1943 
1944 	default:
1945 		/* We implement the SO_SNDLOWAT etc to not be settable
1946 		 * (1003.1g 7).
1947 		 */
1948 		return -ENOPROTOOPT;
1949 	}
1950 
1951 	if (len > lv)
1952 		len = lv;
1953 	if (copy_to_sockptr(optval, &v, len))
1954 		return -EFAULT;
1955 lenout:
1956 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1957 		return -EFAULT;
1958 	return 0;
1959 }
1960 
1961 int sock_getsockopt(struct socket *sock, int level, int optname,
1962 		    char __user *optval, int __user *optlen)
1963 {
1964 	return sk_getsockopt(sock->sk, level, optname,
1965 			     USER_SOCKPTR(optval),
1966 			     USER_SOCKPTR(optlen));
1967 }
1968 
1969 /*
1970  * Initialize an sk_lock.
1971  *
1972  * (We also register the sk_lock with the lock validator.)
1973  */
1974 static inline void sock_lock_init(struct sock *sk)
1975 {
1976 	if (sk->sk_kern_sock)
1977 		sock_lock_init_class_and_name(
1978 			sk,
1979 			af_family_kern_slock_key_strings[sk->sk_family],
1980 			af_family_kern_slock_keys + sk->sk_family,
1981 			af_family_kern_key_strings[sk->sk_family],
1982 			af_family_kern_keys + sk->sk_family);
1983 	else
1984 		sock_lock_init_class_and_name(
1985 			sk,
1986 			af_family_slock_key_strings[sk->sk_family],
1987 			af_family_slock_keys + sk->sk_family,
1988 			af_family_key_strings[sk->sk_family],
1989 			af_family_keys + sk->sk_family);
1990 }
1991 
1992 /*
1993  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1994  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1995  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1996  */
1997 static void sock_copy(struct sock *nsk, const struct sock *osk)
1998 {
1999 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2000 #ifdef CONFIG_SECURITY_NETWORK
2001 	void *sptr = nsk->sk_security;
2002 #endif
2003 
2004 	/* If we move sk_tx_queue_mapping out of the private section,
2005 	 * we must check if sk_tx_queue_clear() is called after
2006 	 * sock_copy() in sk_clone_lock().
2007 	 */
2008 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2009 		     offsetof(struct sock, sk_dontcopy_begin) ||
2010 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2011 		     offsetof(struct sock, sk_dontcopy_end));
2012 
2013 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2014 
2015 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2016 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2017 
2018 #ifdef CONFIG_SECURITY_NETWORK
2019 	nsk->sk_security = sptr;
2020 	security_sk_clone(osk, nsk);
2021 #endif
2022 }
2023 
2024 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2025 		int family)
2026 {
2027 	struct sock *sk;
2028 	struct kmem_cache *slab;
2029 
2030 	slab = prot->slab;
2031 	if (slab != NULL) {
2032 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2033 		if (!sk)
2034 			return sk;
2035 		if (want_init_on_alloc(priority))
2036 			sk_prot_clear_nulls(sk, prot->obj_size);
2037 	} else
2038 		sk = kmalloc(prot->obj_size, priority);
2039 
2040 	if (sk != NULL) {
2041 		if (security_sk_alloc(sk, family, priority))
2042 			goto out_free;
2043 
2044 		if (!try_module_get(prot->owner))
2045 			goto out_free_sec;
2046 	}
2047 
2048 	return sk;
2049 
2050 out_free_sec:
2051 	security_sk_free(sk);
2052 out_free:
2053 	if (slab != NULL)
2054 		kmem_cache_free(slab, sk);
2055 	else
2056 		kfree(sk);
2057 	return NULL;
2058 }
2059 
2060 static void sk_prot_free(struct proto *prot, struct sock *sk)
2061 {
2062 	struct kmem_cache *slab;
2063 	struct module *owner;
2064 
2065 	owner = prot->owner;
2066 	slab = prot->slab;
2067 
2068 	cgroup_sk_free(&sk->sk_cgrp_data);
2069 	mem_cgroup_sk_free(sk);
2070 	security_sk_free(sk);
2071 	if (slab != NULL)
2072 		kmem_cache_free(slab, sk);
2073 	else
2074 		kfree(sk);
2075 	module_put(owner);
2076 }
2077 
2078 /**
2079  *	sk_alloc - All socket objects are allocated here
2080  *	@net: the applicable net namespace
2081  *	@family: protocol family
2082  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2083  *	@prot: struct proto associated with this new sock instance
2084  *	@kern: is this to be a kernel socket?
2085  */
2086 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2087 		      struct proto *prot, int kern)
2088 {
2089 	struct sock *sk;
2090 
2091 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2092 	if (sk) {
2093 		sk->sk_family = family;
2094 		/*
2095 		 * See comment in struct sock definition to understand
2096 		 * why we need sk_prot_creator -acme
2097 		 */
2098 		sk->sk_prot = sk->sk_prot_creator = prot;
2099 		sk->sk_kern_sock = kern;
2100 		sock_lock_init(sk);
2101 		sk->sk_net_refcnt = kern ? 0 : 1;
2102 		if (likely(sk->sk_net_refcnt)) {
2103 			get_net_track(net, &sk->ns_tracker, priority);
2104 			sock_inuse_add(net, 1);
2105 		} else {
2106 			__netns_tracker_alloc(net, &sk->ns_tracker,
2107 					      false, priority);
2108 		}
2109 
2110 		sock_net_set(sk, net);
2111 		refcount_set(&sk->sk_wmem_alloc, 1);
2112 
2113 		mem_cgroup_sk_alloc(sk);
2114 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2115 		sock_update_classid(&sk->sk_cgrp_data);
2116 		sock_update_netprioidx(&sk->sk_cgrp_data);
2117 		sk_tx_queue_clear(sk);
2118 	}
2119 
2120 	return sk;
2121 }
2122 EXPORT_SYMBOL(sk_alloc);
2123 
2124 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2125  * grace period. This is the case for UDP sockets and TCP listeners.
2126  */
2127 static void __sk_destruct(struct rcu_head *head)
2128 {
2129 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2130 	struct sk_filter *filter;
2131 
2132 	if (sk->sk_destruct)
2133 		sk->sk_destruct(sk);
2134 
2135 	filter = rcu_dereference_check(sk->sk_filter,
2136 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2137 	if (filter) {
2138 		sk_filter_uncharge(sk, filter);
2139 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2140 	}
2141 
2142 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2143 
2144 #ifdef CONFIG_BPF_SYSCALL
2145 	bpf_sk_storage_free(sk);
2146 #endif
2147 
2148 	if (atomic_read(&sk->sk_omem_alloc))
2149 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2150 			 __func__, atomic_read(&sk->sk_omem_alloc));
2151 
2152 	if (sk->sk_frag.page) {
2153 		put_page(sk->sk_frag.page);
2154 		sk->sk_frag.page = NULL;
2155 	}
2156 
2157 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2158 	put_cred(sk->sk_peer_cred);
2159 	put_pid(sk->sk_peer_pid);
2160 
2161 	if (likely(sk->sk_net_refcnt))
2162 		put_net_track(sock_net(sk), &sk->ns_tracker);
2163 	else
2164 		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2165 
2166 	sk_prot_free(sk->sk_prot_creator, sk);
2167 }
2168 
2169 void sk_destruct(struct sock *sk)
2170 {
2171 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2172 
2173 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2174 		reuseport_detach_sock(sk);
2175 		use_call_rcu = true;
2176 	}
2177 
2178 	if (use_call_rcu)
2179 		call_rcu(&sk->sk_rcu, __sk_destruct);
2180 	else
2181 		__sk_destruct(&sk->sk_rcu);
2182 }
2183 
2184 static void __sk_free(struct sock *sk)
2185 {
2186 	if (likely(sk->sk_net_refcnt))
2187 		sock_inuse_add(sock_net(sk), -1);
2188 
2189 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2190 		sock_diag_broadcast_destroy(sk);
2191 	else
2192 		sk_destruct(sk);
2193 }
2194 
2195 void sk_free(struct sock *sk)
2196 {
2197 	/*
2198 	 * We subtract one from sk_wmem_alloc and can know if
2199 	 * some packets are still in some tx queue.
2200 	 * If not null, sock_wfree() will call __sk_free(sk) later
2201 	 */
2202 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2203 		__sk_free(sk);
2204 }
2205 EXPORT_SYMBOL(sk_free);
2206 
2207 static void sk_init_common(struct sock *sk)
2208 {
2209 	skb_queue_head_init(&sk->sk_receive_queue);
2210 	skb_queue_head_init(&sk->sk_write_queue);
2211 	skb_queue_head_init(&sk->sk_error_queue);
2212 
2213 	rwlock_init(&sk->sk_callback_lock);
2214 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2215 			af_rlock_keys + sk->sk_family,
2216 			af_family_rlock_key_strings[sk->sk_family]);
2217 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2218 			af_wlock_keys + sk->sk_family,
2219 			af_family_wlock_key_strings[sk->sk_family]);
2220 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2221 			af_elock_keys + sk->sk_family,
2222 			af_family_elock_key_strings[sk->sk_family]);
2223 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2224 			af_callback_keys + sk->sk_family,
2225 			af_family_clock_key_strings[sk->sk_family]);
2226 }
2227 
2228 /**
2229  *	sk_clone_lock - clone a socket, and lock its clone
2230  *	@sk: the socket to clone
2231  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2232  *
2233  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2234  */
2235 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2236 {
2237 	struct proto *prot = READ_ONCE(sk->sk_prot);
2238 	struct sk_filter *filter;
2239 	bool is_charged = true;
2240 	struct sock *newsk;
2241 
2242 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2243 	if (!newsk)
2244 		goto out;
2245 
2246 	sock_copy(newsk, sk);
2247 
2248 	newsk->sk_prot_creator = prot;
2249 
2250 	/* SANITY */
2251 	if (likely(newsk->sk_net_refcnt)) {
2252 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2253 		sock_inuse_add(sock_net(newsk), 1);
2254 	} else {
2255 		/* Kernel sockets are not elevating the struct net refcount.
2256 		 * Instead, use a tracker to more easily detect if a layer
2257 		 * is not properly dismantling its kernel sockets at netns
2258 		 * destroy time.
2259 		 */
2260 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2261 				      false, priority);
2262 	}
2263 	sk_node_init(&newsk->sk_node);
2264 	sock_lock_init(newsk);
2265 	bh_lock_sock(newsk);
2266 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2267 	newsk->sk_backlog.len = 0;
2268 
2269 	atomic_set(&newsk->sk_rmem_alloc, 0);
2270 
2271 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2272 	refcount_set(&newsk->sk_wmem_alloc, 1);
2273 
2274 	atomic_set(&newsk->sk_omem_alloc, 0);
2275 	sk_init_common(newsk);
2276 
2277 	newsk->sk_dst_cache	= NULL;
2278 	newsk->sk_dst_pending_confirm = 0;
2279 	newsk->sk_wmem_queued	= 0;
2280 	newsk->sk_forward_alloc = 0;
2281 	newsk->sk_reserved_mem  = 0;
2282 	atomic_set(&newsk->sk_drops, 0);
2283 	newsk->sk_send_head	= NULL;
2284 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2285 	atomic_set(&newsk->sk_zckey, 0);
2286 
2287 	sock_reset_flag(newsk, SOCK_DONE);
2288 
2289 	/* sk->sk_memcg will be populated at accept() time */
2290 	newsk->sk_memcg = NULL;
2291 
2292 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2293 
2294 	rcu_read_lock();
2295 	filter = rcu_dereference(sk->sk_filter);
2296 	if (filter != NULL)
2297 		/* though it's an empty new sock, the charging may fail
2298 		 * if sysctl_optmem_max was changed between creation of
2299 		 * original socket and cloning
2300 		 */
2301 		is_charged = sk_filter_charge(newsk, filter);
2302 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2303 	rcu_read_unlock();
2304 
2305 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2306 		/* We need to make sure that we don't uncharge the new
2307 		 * socket if we couldn't charge it in the first place
2308 		 * as otherwise we uncharge the parent's filter.
2309 		 */
2310 		if (!is_charged)
2311 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2312 		sk_free_unlock_clone(newsk);
2313 		newsk = NULL;
2314 		goto out;
2315 	}
2316 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2317 
2318 	if (bpf_sk_storage_clone(sk, newsk)) {
2319 		sk_free_unlock_clone(newsk);
2320 		newsk = NULL;
2321 		goto out;
2322 	}
2323 
2324 	/* Clear sk_user_data if parent had the pointer tagged
2325 	 * as not suitable for copying when cloning.
2326 	 */
2327 	if (sk_user_data_is_nocopy(newsk))
2328 		newsk->sk_user_data = NULL;
2329 
2330 	newsk->sk_err	   = 0;
2331 	newsk->sk_err_soft = 0;
2332 	newsk->sk_priority = 0;
2333 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2334 
2335 	/* Before updating sk_refcnt, we must commit prior changes to memory
2336 	 * (Documentation/RCU/rculist_nulls.rst for details)
2337 	 */
2338 	smp_wmb();
2339 	refcount_set(&newsk->sk_refcnt, 2);
2340 
2341 	/* Increment the counter in the same struct proto as the master
2342 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2343 	 * is the same as sk->sk_prot->socks, as this field was copied
2344 	 * with memcpy).
2345 	 *
2346 	 * This _changes_ the previous behaviour, where
2347 	 * tcp_create_openreq_child always was incrementing the
2348 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2349 	 * to be taken into account in all callers. -acme
2350 	 */
2351 	sk_refcnt_debug_inc(newsk);
2352 	sk_set_socket(newsk, NULL);
2353 	sk_tx_queue_clear(newsk);
2354 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2355 
2356 	if (newsk->sk_prot->sockets_allocated)
2357 		sk_sockets_allocated_inc(newsk);
2358 
2359 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2360 		net_enable_timestamp();
2361 out:
2362 	return newsk;
2363 }
2364 EXPORT_SYMBOL_GPL(sk_clone_lock);
2365 
2366 void sk_free_unlock_clone(struct sock *sk)
2367 {
2368 	/* It is still raw copy of parent, so invalidate
2369 	 * destructor and make plain sk_free() */
2370 	sk->sk_destruct = NULL;
2371 	bh_unlock_sock(sk);
2372 	sk_free(sk);
2373 }
2374 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2375 
2376 static void sk_trim_gso_size(struct sock *sk)
2377 {
2378 	if (sk->sk_gso_max_size <= GSO_LEGACY_MAX_SIZE)
2379 		return;
2380 #if IS_ENABLED(CONFIG_IPV6)
2381 	if (sk->sk_family == AF_INET6 &&
2382 	    sk_is_tcp(sk) &&
2383 	    !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
2384 		return;
2385 #endif
2386 	sk->sk_gso_max_size = GSO_LEGACY_MAX_SIZE;
2387 }
2388 
2389 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2390 {
2391 	u32 max_segs = 1;
2392 
2393 	sk_dst_set(sk, dst);
2394 	sk->sk_route_caps = dst->dev->features;
2395 	if (sk_is_tcp(sk))
2396 		sk->sk_route_caps |= NETIF_F_GSO;
2397 	if (sk->sk_route_caps & NETIF_F_GSO)
2398 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2399 	if (unlikely(sk->sk_gso_disabled))
2400 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2401 	if (sk_can_gso(sk)) {
2402 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2403 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2404 		} else {
2405 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2406 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2407 			sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2408 			sk_trim_gso_size(sk);
2409 			sk->sk_gso_max_size -= (MAX_TCP_HEADER + 1);
2410 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2411 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2412 		}
2413 	}
2414 	sk->sk_gso_max_segs = max_segs;
2415 }
2416 EXPORT_SYMBOL_GPL(sk_setup_caps);
2417 
2418 /*
2419  *	Simple resource managers for sockets.
2420  */
2421 
2422 
2423 /*
2424  * Write buffer destructor automatically called from kfree_skb.
2425  */
2426 void sock_wfree(struct sk_buff *skb)
2427 {
2428 	struct sock *sk = skb->sk;
2429 	unsigned int len = skb->truesize;
2430 	bool free;
2431 
2432 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2433 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2434 		    sk->sk_write_space == sock_def_write_space) {
2435 			rcu_read_lock();
2436 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2437 			sock_def_write_space_wfree(sk);
2438 			rcu_read_unlock();
2439 			if (unlikely(free))
2440 				__sk_free(sk);
2441 			return;
2442 		}
2443 
2444 		/*
2445 		 * Keep a reference on sk_wmem_alloc, this will be released
2446 		 * after sk_write_space() call
2447 		 */
2448 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2449 		sk->sk_write_space(sk);
2450 		len = 1;
2451 	}
2452 	/*
2453 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2454 	 * could not do because of in-flight packets
2455 	 */
2456 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2457 		__sk_free(sk);
2458 }
2459 EXPORT_SYMBOL(sock_wfree);
2460 
2461 /* This variant of sock_wfree() is used by TCP,
2462  * since it sets SOCK_USE_WRITE_QUEUE.
2463  */
2464 void __sock_wfree(struct sk_buff *skb)
2465 {
2466 	struct sock *sk = skb->sk;
2467 
2468 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2469 		__sk_free(sk);
2470 }
2471 
2472 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2473 {
2474 	skb_orphan(skb);
2475 	skb->sk = sk;
2476 #ifdef CONFIG_INET
2477 	if (unlikely(!sk_fullsock(sk))) {
2478 		skb->destructor = sock_edemux;
2479 		sock_hold(sk);
2480 		return;
2481 	}
2482 #endif
2483 	skb->destructor = sock_wfree;
2484 	skb_set_hash_from_sk(skb, sk);
2485 	/*
2486 	 * We used to take a refcount on sk, but following operation
2487 	 * is enough to guarantee sk_free() wont free this sock until
2488 	 * all in-flight packets are completed
2489 	 */
2490 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2491 }
2492 EXPORT_SYMBOL(skb_set_owner_w);
2493 
2494 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2495 {
2496 #ifdef CONFIG_TLS_DEVICE
2497 	/* Drivers depend on in-order delivery for crypto offload,
2498 	 * partial orphan breaks out-of-order-OK logic.
2499 	 */
2500 	if (skb->decrypted)
2501 		return false;
2502 #endif
2503 	return (skb->destructor == sock_wfree ||
2504 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2505 }
2506 
2507 /* This helper is used by netem, as it can hold packets in its
2508  * delay queue. We want to allow the owner socket to send more
2509  * packets, as if they were already TX completed by a typical driver.
2510  * But we also want to keep skb->sk set because some packet schedulers
2511  * rely on it (sch_fq for example).
2512  */
2513 void skb_orphan_partial(struct sk_buff *skb)
2514 {
2515 	if (skb_is_tcp_pure_ack(skb))
2516 		return;
2517 
2518 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2519 		return;
2520 
2521 	skb_orphan(skb);
2522 }
2523 EXPORT_SYMBOL(skb_orphan_partial);
2524 
2525 /*
2526  * Read buffer destructor automatically called from kfree_skb.
2527  */
2528 void sock_rfree(struct sk_buff *skb)
2529 {
2530 	struct sock *sk = skb->sk;
2531 	unsigned int len = skb->truesize;
2532 
2533 	atomic_sub(len, &sk->sk_rmem_alloc);
2534 	sk_mem_uncharge(sk, len);
2535 }
2536 EXPORT_SYMBOL(sock_rfree);
2537 
2538 /*
2539  * Buffer destructor for skbs that are not used directly in read or write
2540  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2541  */
2542 void sock_efree(struct sk_buff *skb)
2543 {
2544 	sock_put(skb->sk);
2545 }
2546 EXPORT_SYMBOL(sock_efree);
2547 
2548 /* Buffer destructor for prefetch/receive path where reference count may
2549  * not be held, e.g. for listen sockets.
2550  */
2551 #ifdef CONFIG_INET
2552 void sock_pfree(struct sk_buff *skb)
2553 {
2554 	if (sk_is_refcounted(skb->sk))
2555 		sock_gen_put(skb->sk);
2556 }
2557 EXPORT_SYMBOL(sock_pfree);
2558 #endif /* CONFIG_INET */
2559 
2560 kuid_t sock_i_uid(struct sock *sk)
2561 {
2562 	kuid_t uid;
2563 
2564 	read_lock_bh(&sk->sk_callback_lock);
2565 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2566 	read_unlock_bh(&sk->sk_callback_lock);
2567 	return uid;
2568 }
2569 EXPORT_SYMBOL(sock_i_uid);
2570 
2571 unsigned long sock_i_ino(struct sock *sk)
2572 {
2573 	unsigned long ino;
2574 
2575 	read_lock_bh(&sk->sk_callback_lock);
2576 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2577 	read_unlock_bh(&sk->sk_callback_lock);
2578 	return ino;
2579 }
2580 EXPORT_SYMBOL(sock_i_ino);
2581 
2582 /*
2583  * Allocate a skb from the socket's send buffer.
2584  */
2585 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2586 			     gfp_t priority)
2587 {
2588 	if (force ||
2589 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2590 		struct sk_buff *skb = alloc_skb(size, priority);
2591 
2592 		if (skb) {
2593 			skb_set_owner_w(skb, sk);
2594 			return skb;
2595 		}
2596 	}
2597 	return NULL;
2598 }
2599 EXPORT_SYMBOL(sock_wmalloc);
2600 
2601 static void sock_ofree(struct sk_buff *skb)
2602 {
2603 	struct sock *sk = skb->sk;
2604 
2605 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2606 }
2607 
2608 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2609 			     gfp_t priority)
2610 {
2611 	struct sk_buff *skb;
2612 
2613 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2614 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2615 	    READ_ONCE(sysctl_optmem_max))
2616 		return NULL;
2617 
2618 	skb = alloc_skb(size, priority);
2619 	if (!skb)
2620 		return NULL;
2621 
2622 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2623 	skb->sk = sk;
2624 	skb->destructor = sock_ofree;
2625 	return skb;
2626 }
2627 
2628 /*
2629  * Allocate a memory block from the socket's option memory buffer.
2630  */
2631 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2632 {
2633 	int optmem_max = READ_ONCE(sysctl_optmem_max);
2634 
2635 	if ((unsigned int)size <= optmem_max &&
2636 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2637 		void *mem;
2638 		/* First do the add, to avoid the race if kmalloc
2639 		 * might sleep.
2640 		 */
2641 		atomic_add(size, &sk->sk_omem_alloc);
2642 		mem = kmalloc(size, priority);
2643 		if (mem)
2644 			return mem;
2645 		atomic_sub(size, &sk->sk_omem_alloc);
2646 	}
2647 	return NULL;
2648 }
2649 EXPORT_SYMBOL(sock_kmalloc);
2650 
2651 /* Free an option memory block. Note, we actually want the inline
2652  * here as this allows gcc to detect the nullify and fold away the
2653  * condition entirely.
2654  */
2655 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2656 				  const bool nullify)
2657 {
2658 	if (WARN_ON_ONCE(!mem))
2659 		return;
2660 	if (nullify)
2661 		kfree_sensitive(mem);
2662 	else
2663 		kfree(mem);
2664 	atomic_sub(size, &sk->sk_omem_alloc);
2665 }
2666 
2667 void sock_kfree_s(struct sock *sk, void *mem, int size)
2668 {
2669 	__sock_kfree_s(sk, mem, size, false);
2670 }
2671 EXPORT_SYMBOL(sock_kfree_s);
2672 
2673 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2674 {
2675 	__sock_kfree_s(sk, mem, size, true);
2676 }
2677 EXPORT_SYMBOL(sock_kzfree_s);
2678 
2679 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2680    I think, these locks should be removed for datagram sockets.
2681  */
2682 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2683 {
2684 	DEFINE_WAIT(wait);
2685 
2686 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2687 	for (;;) {
2688 		if (!timeo)
2689 			break;
2690 		if (signal_pending(current))
2691 			break;
2692 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2693 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2694 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2695 			break;
2696 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2697 			break;
2698 		if (sk->sk_err)
2699 			break;
2700 		timeo = schedule_timeout(timeo);
2701 	}
2702 	finish_wait(sk_sleep(sk), &wait);
2703 	return timeo;
2704 }
2705 
2706 
2707 /*
2708  *	Generic send/receive buffer handlers
2709  */
2710 
2711 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2712 				     unsigned long data_len, int noblock,
2713 				     int *errcode, int max_page_order)
2714 {
2715 	struct sk_buff *skb;
2716 	long timeo;
2717 	int err;
2718 
2719 	timeo = sock_sndtimeo(sk, noblock);
2720 	for (;;) {
2721 		err = sock_error(sk);
2722 		if (err != 0)
2723 			goto failure;
2724 
2725 		err = -EPIPE;
2726 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2727 			goto failure;
2728 
2729 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2730 			break;
2731 
2732 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2733 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2734 		err = -EAGAIN;
2735 		if (!timeo)
2736 			goto failure;
2737 		if (signal_pending(current))
2738 			goto interrupted;
2739 		timeo = sock_wait_for_wmem(sk, timeo);
2740 	}
2741 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2742 				   errcode, sk->sk_allocation);
2743 	if (skb)
2744 		skb_set_owner_w(skb, sk);
2745 	return skb;
2746 
2747 interrupted:
2748 	err = sock_intr_errno(timeo);
2749 failure:
2750 	*errcode = err;
2751 	return NULL;
2752 }
2753 EXPORT_SYMBOL(sock_alloc_send_pskb);
2754 
2755 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2756 		     struct sockcm_cookie *sockc)
2757 {
2758 	u32 tsflags;
2759 
2760 	switch (cmsg->cmsg_type) {
2761 	case SO_MARK:
2762 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2763 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2764 			return -EPERM;
2765 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2766 			return -EINVAL;
2767 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2768 		break;
2769 	case SO_TIMESTAMPING_OLD:
2770 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2771 			return -EINVAL;
2772 
2773 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2774 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2775 			return -EINVAL;
2776 
2777 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2778 		sockc->tsflags |= tsflags;
2779 		break;
2780 	case SCM_TXTIME:
2781 		if (!sock_flag(sk, SOCK_TXTIME))
2782 			return -EINVAL;
2783 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2784 			return -EINVAL;
2785 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2786 		break;
2787 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2788 	case SCM_RIGHTS:
2789 	case SCM_CREDENTIALS:
2790 		break;
2791 	default:
2792 		return -EINVAL;
2793 	}
2794 	return 0;
2795 }
2796 EXPORT_SYMBOL(__sock_cmsg_send);
2797 
2798 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2799 		   struct sockcm_cookie *sockc)
2800 {
2801 	struct cmsghdr *cmsg;
2802 	int ret;
2803 
2804 	for_each_cmsghdr(cmsg, msg) {
2805 		if (!CMSG_OK(msg, cmsg))
2806 			return -EINVAL;
2807 		if (cmsg->cmsg_level != SOL_SOCKET)
2808 			continue;
2809 		ret = __sock_cmsg_send(sk, cmsg, sockc);
2810 		if (ret)
2811 			return ret;
2812 	}
2813 	return 0;
2814 }
2815 EXPORT_SYMBOL(sock_cmsg_send);
2816 
2817 static void sk_enter_memory_pressure(struct sock *sk)
2818 {
2819 	if (!sk->sk_prot->enter_memory_pressure)
2820 		return;
2821 
2822 	sk->sk_prot->enter_memory_pressure(sk);
2823 }
2824 
2825 static void sk_leave_memory_pressure(struct sock *sk)
2826 {
2827 	if (sk->sk_prot->leave_memory_pressure) {
2828 		sk->sk_prot->leave_memory_pressure(sk);
2829 	} else {
2830 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2831 
2832 		if (memory_pressure && READ_ONCE(*memory_pressure))
2833 			WRITE_ONCE(*memory_pressure, 0);
2834 	}
2835 }
2836 
2837 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2838 
2839 /**
2840  * skb_page_frag_refill - check that a page_frag contains enough room
2841  * @sz: minimum size of the fragment we want to get
2842  * @pfrag: pointer to page_frag
2843  * @gfp: priority for memory allocation
2844  *
2845  * Note: While this allocator tries to use high order pages, there is
2846  * no guarantee that allocations succeed. Therefore, @sz MUST be
2847  * less or equal than PAGE_SIZE.
2848  */
2849 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2850 {
2851 	if (pfrag->page) {
2852 		if (page_ref_count(pfrag->page) == 1) {
2853 			pfrag->offset = 0;
2854 			return true;
2855 		}
2856 		if (pfrag->offset + sz <= pfrag->size)
2857 			return true;
2858 		put_page(pfrag->page);
2859 	}
2860 
2861 	pfrag->offset = 0;
2862 	if (SKB_FRAG_PAGE_ORDER &&
2863 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2864 		/* Avoid direct reclaim but allow kswapd to wake */
2865 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2866 					  __GFP_COMP | __GFP_NOWARN |
2867 					  __GFP_NORETRY,
2868 					  SKB_FRAG_PAGE_ORDER);
2869 		if (likely(pfrag->page)) {
2870 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2871 			return true;
2872 		}
2873 	}
2874 	pfrag->page = alloc_page(gfp);
2875 	if (likely(pfrag->page)) {
2876 		pfrag->size = PAGE_SIZE;
2877 		return true;
2878 	}
2879 	return false;
2880 }
2881 EXPORT_SYMBOL(skb_page_frag_refill);
2882 
2883 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2884 {
2885 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2886 		return true;
2887 
2888 	sk_enter_memory_pressure(sk);
2889 	sk_stream_moderate_sndbuf(sk);
2890 	return false;
2891 }
2892 EXPORT_SYMBOL(sk_page_frag_refill);
2893 
2894 void __lock_sock(struct sock *sk)
2895 	__releases(&sk->sk_lock.slock)
2896 	__acquires(&sk->sk_lock.slock)
2897 {
2898 	DEFINE_WAIT(wait);
2899 
2900 	for (;;) {
2901 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2902 					TASK_UNINTERRUPTIBLE);
2903 		spin_unlock_bh(&sk->sk_lock.slock);
2904 		schedule();
2905 		spin_lock_bh(&sk->sk_lock.slock);
2906 		if (!sock_owned_by_user(sk))
2907 			break;
2908 	}
2909 	finish_wait(&sk->sk_lock.wq, &wait);
2910 }
2911 
2912 void __release_sock(struct sock *sk)
2913 	__releases(&sk->sk_lock.slock)
2914 	__acquires(&sk->sk_lock.slock)
2915 {
2916 	struct sk_buff *skb, *next;
2917 
2918 	while ((skb = sk->sk_backlog.head) != NULL) {
2919 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2920 
2921 		spin_unlock_bh(&sk->sk_lock.slock);
2922 
2923 		do {
2924 			next = skb->next;
2925 			prefetch(next);
2926 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2927 			skb_mark_not_on_list(skb);
2928 			sk_backlog_rcv(sk, skb);
2929 
2930 			cond_resched();
2931 
2932 			skb = next;
2933 		} while (skb != NULL);
2934 
2935 		spin_lock_bh(&sk->sk_lock.slock);
2936 	}
2937 
2938 	/*
2939 	 * Doing the zeroing here guarantee we can not loop forever
2940 	 * while a wild producer attempts to flood us.
2941 	 */
2942 	sk->sk_backlog.len = 0;
2943 }
2944 
2945 void __sk_flush_backlog(struct sock *sk)
2946 {
2947 	spin_lock_bh(&sk->sk_lock.slock);
2948 	__release_sock(sk);
2949 	spin_unlock_bh(&sk->sk_lock.slock);
2950 }
2951 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2952 
2953 /**
2954  * sk_wait_data - wait for data to arrive at sk_receive_queue
2955  * @sk:    sock to wait on
2956  * @timeo: for how long
2957  * @skb:   last skb seen on sk_receive_queue
2958  *
2959  * Now socket state including sk->sk_err is changed only under lock,
2960  * hence we may omit checks after joining wait queue.
2961  * We check receive queue before schedule() only as optimization;
2962  * it is very likely that release_sock() added new data.
2963  */
2964 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2965 {
2966 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2967 	int rc;
2968 
2969 	add_wait_queue(sk_sleep(sk), &wait);
2970 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2971 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2972 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2973 	remove_wait_queue(sk_sleep(sk), &wait);
2974 	return rc;
2975 }
2976 EXPORT_SYMBOL(sk_wait_data);
2977 
2978 /**
2979  *	__sk_mem_raise_allocated - increase memory_allocated
2980  *	@sk: socket
2981  *	@size: memory size to allocate
2982  *	@amt: pages to allocate
2983  *	@kind: allocation type
2984  *
2985  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2986  */
2987 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2988 {
2989 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2990 	struct proto *prot = sk->sk_prot;
2991 	bool charged = true;
2992 	long allocated;
2993 
2994 	sk_memory_allocated_add(sk, amt);
2995 	allocated = sk_memory_allocated(sk);
2996 	if (memcg_charge &&
2997 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2998 						gfp_memcg_charge())))
2999 		goto suppress_allocation;
3000 
3001 	/* Under limit. */
3002 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3003 		sk_leave_memory_pressure(sk);
3004 		return 1;
3005 	}
3006 
3007 	/* Under pressure. */
3008 	if (allocated > sk_prot_mem_limits(sk, 1))
3009 		sk_enter_memory_pressure(sk);
3010 
3011 	/* Over hard limit. */
3012 	if (allocated > sk_prot_mem_limits(sk, 2))
3013 		goto suppress_allocation;
3014 
3015 	/* guarantee minimum buffer size under pressure */
3016 	if (kind == SK_MEM_RECV) {
3017 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3018 			return 1;
3019 
3020 	} else { /* SK_MEM_SEND */
3021 		int wmem0 = sk_get_wmem0(sk, prot);
3022 
3023 		if (sk->sk_type == SOCK_STREAM) {
3024 			if (sk->sk_wmem_queued < wmem0)
3025 				return 1;
3026 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3027 				return 1;
3028 		}
3029 	}
3030 
3031 	if (sk_has_memory_pressure(sk)) {
3032 		u64 alloc;
3033 
3034 		if (!sk_under_memory_pressure(sk))
3035 			return 1;
3036 		alloc = sk_sockets_allocated_read_positive(sk);
3037 		if (sk_prot_mem_limits(sk, 2) > alloc *
3038 		    sk_mem_pages(sk->sk_wmem_queued +
3039 				 atomic_read(&sk->sk_rmem_alloc) +
3040 				 sk->sk_forward_alloc))
3041 			return 1;
3042 	}
3043 
3044 suppress_allocation:
3045 
3046 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3047 		sk_stream_moderate_sndbuf(sk);
3048 
3049 		/* Fail only if socket is _under_ its sndbuf.
3050 		 * In this case we cannot block, so that we have to fail.
3051 		 */
3052 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3053 			/* Force charge with __GFP_NOFAIL */
3054 			if (memcg_charge && !charged) {
3055 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3056 					gfp_memcg_charge() | __GFP_NOFAIL);
3057 			}
3058 			return 1;
3059 		}
3060 	}
3061 
3062 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3063 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3064 
3065 	sk_memory_allocated_sub(sk, amt);
3066 
3067 	if (memcg_charge && charged)
3068 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3069 
3070 	return 0;
3071 }
3072 
3073 /**
3074  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3075  *	@sk: socket
3076  *	@size: memory size to allocate
3077  *	@kind: allocation type
3078  *
3079  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3080  *	rmem allocation. This function assumes that protocols which have
3081  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3082  */
3083 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3084 {
3085 	int ret, amt = sk_mem_pages(size);
3086 
3087 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3088 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3089 	if (!ret)
3090 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3091 	return ret;
3092 }
3093 EXPORT_SYMBOL(__sk_mem_schedule);
3094 
3095 /**
3096  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3097  *	@sk: socket
3098  *	@amount: number of quanta
3099  *
3100  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3101  */
3102 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3103 {
3104 	sk_memory_allocated_sub(sk, amount);
3105 
3106 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3107 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3108 
3109 	if (sk_under_memory_pressure(sk) &&
3110 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3111 		sk_leave_memory_pressure(sk);
3112 }
3113 
3114 /**
3115  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3116  *	@sk: socket
3117  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3118  */
3119 void __sk_mem_reclaim(struct sock *sk, int amount)
3120 {
3121 	amount >>= PAGE_SHIFT;
3122 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3123 	__sk_mem_reduce_allocated(sk, amount);
3124 }
3125 EXPORT_SYMBOL(__sk_mem_reclaim);
3126 
3127 int sk_set_peek_off(struct sock *sk, int val)
3128 {
3129 	sk->sk_peek_off = val;
3130 	return 0;
3131 }
3132 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3133 
3134 /*
3135  * Set of default routines for initialising struct proto_ops when
3136  * the protocol does not support a particular function. In certain
3137  * cases where it makes no sense for a protocol to have a "do nothing"
3138  * function, some default processing is provided.
3139  */
3140 
3141 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3142 {
3143 	return -EOPNOTSUPP;
3144 }
3145 EXPORT_SYMBOL(sock_no_bind);
3146 
3147 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3148 		    int len, int flags)
3149 {
3150 	return -EOPNOTSUPP;
3151 }
3152 EXPORT_SYMBOL(sock_no_connect);
3153 
3154 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3155 {
3156 	return -EOPNOTSUPP;
3157 }
3158 EXPORT_SYMBOL(sock_no_socketpair);
3159 
3160 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3161 		   bool kern)
3162 {
3163 	return -EOPNOTSUPP;
3164 }
3165 EXPORT_SYMBOL(sock_no_accept);
3166 
3167 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3168 		    int peer)
3169 {
3170 	return -EOPNOTSUPP;
3171 }
3172 EXPORT_SYMBOL(sock_no_getname);
3173 
3174 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3175 {
3176 	return -EOPNOTSUPP;
3177 }
3178 EXPORT_SYMBOL(sock_no_ioctl);
3179 
3180 int sock_no_listen(struct socket *sock, int backlog)
3181 {
3182 	return -EOPNOTSUPP;
3183 }
3184 EXPORT_SYMBOL(sock_no_listen);
3185 
3186 int sock_no_shutdown(struct socket *sock, int how)
3187 {
3188 	return -EOPNOTSUPP;
3189 }
3190 EXPORT_SYMBOL(sock_no_shutdown);
3191 
3192 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3193 {
3194 	return -EOPNOTSUPP;
3195 }
3196 EXPORT_SYMBOL(sock_no_sendmsg);
3197 
3198 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3199 {
3200 	return -EOPNOTSUPP;
3201 }
3202 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3203 
3204 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3205 		    int flags)
3206 {
3207 	return -EOPNOTSUPP;
3208 }
3209 EXPORT_SYMBOL(sock_no_recvmsg);
3210 
3211 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3212 {
3213 	/* Mirror missing mmap method error code */
3214 	return -ENODEV;
3215 }
3216 EXPORT_SYMBOL(sock_no_mmap);
3217 
3218 /*
3219  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3220  * various sock-based usage counts.
3221  */
3222 void __receive_sock(struct file *file)
3223 {
3224 	struct socket *sock;
3225 
3226 	sock = sock_from_file(file);
3227 	if (sock) {
3228 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3229 		sock_update_classid(&sock->sk->sk_cgrp_data);
3230 	}
3231 }
3232 
3233 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3234 {
3235 	ssize_t res;
3236 	struct msghdr msg = {.msg_flags = flags};
3237 	struct kvec iov;
3238 	char *kaddr = kmap(page);
3239 	iov.iov_base = kaddr + offset;
3240 	iov.iov_len = size;
3241 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3242 	kunmap(page);
3243 	return res;
3244 }
3245 EXPORT_SYMBOL(sock_no_sendpage);
3246 
3247 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3248 				int offset, size_t size, int flags)
3249 {
3250 	ssize_t res;
3251 	struct msghdr msg = {.msg_flags = flags};
3252 	struct kvec iov;
3253 	char *kaddr = kmap(page);
3254 
3255 	iov.iov_base = kaddr + offset;
3256 	iov.iov_len = size;
3257 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3258 	kunmap(page);
3259 	return res;
3260 }
3261 EXPORT_SYMBOL(sock_no_sendpage_locked);
3262 
3263 /*
3264  *	Default Socket Callbacks
3265  */
3266 
3267 static void sock_def_wakeup(struct sock *sk)
3268 {
3269 	struct socket_wq *wq;
3270 
3271 	rcu_read_lock();
3272 	wq = rcu_dereference(sk->sk_wq);
3273 	if (skwq_has_sleeper(wq))
3274 		wake_up_interruptible_all(&wq->wait);
3275 	rcu_read_unlock();
3276 }
3277 
3278 static void sock_def_error_report(struct sock *sk)
3279 {
3280 	struct socket_wq *wq;
3281 
3282 	rcu_read_lock();
3283 	wq = rcu_dereference(sk->sk_wq);
3284 	if (skwq_has_sleeper(wq))
3285 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3286 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3287 	rcu_read_unlock();
3288 }
3289 
3290 void sock_def_readable(struct sock *sk)
3291 {
3292 	struct socket_wq *wq;
3293 
3294 	rcu_read_lock();
3295 	wq = rcu_dereference(sk->sk_wq);
3296 	if (skwq_has_sleeper(wq))
3297 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3298 						EPOLLRDNORM | EPOLLRDBAND);
3299 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3300 	rcu_read_unlock();
3301 }
3302 
3303 static void sock_def_write_space(struct sock *sk)
3304 {
3305 	struct socket_wq *wq;
3306 
3307 	rcu_read_lock();
3308 
3309 	/* Do not wake up a writer until he can make "significant"
3310 	 * progress.  --DaveM
3311 	 */
3312 	if (sock_writeable(sk)) {
3313 		wq = rcu_dereference(sk->sk_wq);
3314 		if (skwq_has_sleeper(wq))
3315 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3316 						EPOLLWRNORM | EPOLLWRBAND);
3317 
3318 		/* Should agree with poll, otherwise some programs break */
3319 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3320 	}
3321 
3322 	rcu_read_unlock();
3323 }
3324 
3325 /* An optimised version of sock_def_write_space(), should only be called
3326  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3327  * ->sk_wmem_alloc.
3328  */
3329 static void sock_def_write_space_wfree(struct sock *sk)
3330 {
3331 	/* Do not wake up a writer until he can make "significant"
3332 	 * progress.  --DaveM
3333 	 */
3334 	if (sock_writeable(sk)) {
3335 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3336 
3337 		/* rely on refcount_sub from sock_wfree() */
3338 		smp_mb__after_atomic();
3339 		if (wq && waitqueue_active(&wq->wait))
3340 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3341 						EPOLLWRNORM | EPOLLWRBAND);
3342 
3343 		/* Should agree with poll, otherwise some programs break */
3344 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3345 	}
3346 }
3347 
3348 static void sock_def_destruct(struct sock *sk)
3349 {
3350 }
3351 
3352 void sk_send_sigurg(struct sock *sk)
3353 {
3354 	if (sk->sk_socket && sk->sk_socket->file)
3355 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3356 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3357 }
3358 EXPORT_SYMBOL(sk_send_sigurg);
3359 
3360 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3361 		    unsigned long expires)
3362 {
3363 	if (!mod_timer(timer, expires))
3364 		sock_hold(sk);
3365 }
3366 EXPORT_SYMBOL(sk_reset_timer);
3367 
3368 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3369 {
3370 	if (del_timer(timer))
3371 		__sock_put(sk);
3372 }
3373 EXPORT_SYMBOL(sk_stop_timer);
3374 
3375 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3376 {
3377 	if (del_timer_sync(timer))
3378 		__sock_put(sk);
3379 }
3380 EXPORT_SYMBOL(sk_stop_timer_sync);
3381 
3382 void sock_init_data(struct socket *sock, struct sock *sk)
3383 {
3384 	sk_init_common(sk);
3385 	sk->sk_send_head	=	NULL;
3386 
3387 	timer_setup(&sk->sk_timer, NULL, 0);
3388 
3389 	sk->sk_allocation	=	GFP_KERNEL;
3390 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3391 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3392 	sk->sk_state		=	TCP_CLOSE;
3393 	sk->sk_use_task_frag	=	true;
3394 	sk_set_socket(sk, sock);
3395 
3396 	sock_set_flag(sk, SOCK_ZAPPED);
3397 
3398 	if (sock) {
3399 		sk->sk_type	=	sock->type;
3400 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3401 		sock->sk	=	sk;
3402 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3403 	} else {
3404 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3405 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3406 	}
3407 
3408 	rwlock_init(&sk->sk_callback_lock);
3409 	if (sk->sk_kern_sock)
3410 		lockdep_set_class_and_name(
3411 			&sk->sk_callback_lock,
3412 			af_kern_callback_keys + sk->sk_family,
3413 			af_family_kern_clock_key_strings[sk->sk_family]);
3414 	else
3415 		lockdep_set_class_and_name(
3416 			&sk->sk_callback_lock,
3417 			af_callback_keys + sk->sk_family,
3418 			af_family_clock_key_strings[sk->sk_family]);
3419 
3420 	sk->sk_state_change	=	sock_def_wakeup;
3421 	sk->sk_data_ready	=	sock_def_readable;
3422 	sk->sk_write_space	=	sock_def_write_space;
3423 	sk->sk_error_report	=	sock_def_error_report;
3424 	sk->sk_destruct		=	sock_def_destruct;
3425 
3426 	sk->sk_frag.page	=	NULL;
3427 	sk->sk_frag.offset	=	0;
3428 	sk->sk_peek_off		=	-1;
3429 
3430 	sk->sk_peer_pid 	=	NULL;
3431 	sk->sk_peer_cred	=	NULL;
3432 	spin_lock_init(&sk->sk_peer_lock);
3433 
3434 	sk->sk_write_pending	=	0;
3435 	sk->sk_rcvlowat		=	1;
3436 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3437 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3438 
3439 	sk->sk_stamp = SK_DEFAULT_STAMP;
3440 #if BITS_PER_LONG==32
3441 	seqlock_init(&sk->sk_stamp_seq);
3442 #endif
3443 	atomic_set(&sk->sk_zckey, 0);
3444 
3445 #ifdef CONFIG_NET_RX_BUSY_POLL
3446 	sk->sk_napi_id		=	0;
3447 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3448 #endif
3449 
3450 	sk->sk_max_pacing_rate = ~0UL;
3451 	sk->sk_pacing_rate = ~0UL;
3452 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3453 	sk->sk_incoming_cpu = -1;
3454 	sk->sk_txrehash = SOCK_TXREHASH_DEFAULT;
3455 
3456 	sk_rx_queue_clear(sk);
3457 	/*
3458 	 * Before updating sk_refcnt, we must commit prior changes to memory
3459 	 * (Documentation/RCU/rculist_nulls.rst for details)
3460 	 */
3461 	smp_wmb();
3462 	refcount_set(&sk->sk_refcnt, 1);
3463 	atomic_set(&sk->sk_drops, 0);
3464 }
3465 EXPORT_SYMBOL(sock_init_data);
3466 
3467 void lock_sock_nested(struct sock *sk, int subclass)
3468 {
3469 	/* The sk_lock has mutex_lock() semantics here. */
3470 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3471 
3472 	might_sleep();
3473 	spin_lock_bh(&sk->sk_lock.slock);
3474 	if (sock_owned_by_user_nocheck(sk))
3475 		__lock_sock(sk);
3476 	sk->sk_lock.owned = 1;
3477 	spin_unlock_bh(&sk->sk_lock.slock);
3478 }
3479 EXPORT_SYMBOL(lock_sock_nested);
3480 
3481 void release_sock(struct sock *sk)
3482 {
3483 	spin_lock_bh(&sk->sk_lock.slock);
3484 	if (sk->sk_backlog.tail)
3485 		__release_sock(sk);
3486 
3487 	/* Warning : release_cb() might need to release sk ownership,
3488 	 * ie call sock_release_ownership(sk) before us.
3489 	 */
3490 	if (sk->sk_prot->release_cb)
3491 		sk->sk_prot->release_cb(sk);
3492 
3493 	sock_release_ownership(sk);
3494 	if (waitqueue_active(&sk->sk_lock.wq))
3495 		wake_up(&sk->sk_lock.wq);
3496 	spin_unlock_bh(&sk->sk_lock.slock);
3497 }
3498 EXPORT_SYMBOL(release_sock);
3499 
3500 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3501 {
3502 	might_sleep();
3503 	spin_lock_bh(&sk->sk_lock.slock);
3504 
3505 	if (!sock_owned_by_user_nocheck(sk)) {
3506 		/*
3507 		 * Fast path return with bottom halves disabled and
3508 		 * sock::sk_lock.slock held.
3509 		 *
3510 		 * The 'mutex' is not contended and holding
3511 		 * sock::sk_lock.slock prevents all other lockers to
3512 		 * proceed so the corresponding unlock_sock_fast() can
3513 		 * avoid the slow path of release_sock() completely and
3514 		 * just release slock.
3515 		 *
3516 		 * From a semantical POV this is equivalent to 'acquiring'
3517 		 * the 'mutex', hence the corresponding lockdep
3518 		 * mutex_release() has to happen in the fast path of
3519 		 * unlock_sock_fast().
3520 		 */
3521 		return false;
3522 	}
3523 
3524 	__lock_sock(sk);
3525 	sk->sk_lock.owned = 1;
3526 	__acquire(&sk->sk_lock.slock);
3527 	spin_unlock_bh(&sk->sk_lock.slock);
3528 	return true;
3529 }
3530 EXPORT_SYMBOL(__lock_sock_fast);
3531 
3532 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3533 		   bool timeval, bool time32)
3534 {
3535 	struct sock *sk = sock->sk;
3536 	struct timespec64 ts;
3537 
3538 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3539 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3540 	if (ts.tv_sec == -1)
3541 		return -ENOENT;
3542 	if (ts.tv_sec == 0) {
3543 		ktime_t kt = ktime_get_real();
3544 		sock_write_timestamp(sk, kt);
3545 		ts = ktime_to_timespec64(kt);
3546 	}
3547 
3548 	if (timeval)
3549 		ts.tv_nsec /= 1000;
3550 
3551 #ifdef CONFIG_COMPAT_32BIT_TIME
3552 	if (time32)
3553 		return put_old_timespec32(&ts, userstamp);
3554 #endif
3555 #ifdef CONFIG_SPARC64
3556 	/* beware of padding in sparc64 timeval */
3557 	if (timeval && !in_compat_syscall()) {
3558 		struct __kernel_old_timeval __user tv = {
3559 			.tv_sec = ts.tv_sec,
3560 			.tv_usec = ts.tv_nsec,
3561 		};
3562 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3563 			return -EFAULT;
3564 		return 0;
3565 	}
3566 #endif
3567 	return put_timespec64(&ts, userstamp);
3568 }
3569 EXPORT_SYMBOL(sock_gettstamp);
3570 
3571 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3572 {
3573 	if (!sock_flag(sk, flag)) {
3574 		unsigned long previous_flags = sk->sk_flags;
3575 
3576 		sock_set_flag(sk, flag);
3577 		/*
3578 		 * we just set one of the two flags which require net
3579 		 * time stamping, but time stamping might have been on
3580 		 * already because of the other one
3581 		 */
3582 		if (sock_needs_netstamp(sk) &&
3583 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3584 			net_enable_timestamp();
3585 	}
3586 }
3587 
3588 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3589 		       int level, int type)
3590 {
3591 	struct sock_exterr_skb *serr;
3592 	struct sk_buff *skb;
3593 	int copied, err;
3594 
3595 	err = -EAGAIN;
3596 	skb = sock_dequeue_err_skb(sk);
3597 	if (skb == NULL)
3598 		goto out;
3599 
3600 	copied = skb->len;
3601 	if (copied > len) {
3602 		msg->msg_flags |= MSG_TRUNC;
3603 		copied = len;
3604 	}
3605 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3606 	if (err)
3607 		goto out_free_skb;
3608 
3609 	sock_recv_timestamp(msg, sk, skb);
3610 
3611 	serr = SKB_EXT_ERR(skb);
3612 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3613 
3614 	msg->msg_flags |= MSG_ERRQUEUE;
3615 	err = copied;
3616 
3617 out_free_skb:
3618 	kfree_skb(skb);
3619 out:
3620 	return err;
3621 }
3622 EXPORT_SYMBOL(sock_recv_errqueue);
3623 
3624 /*
3625  *	Get a socket option on an socket.
3626  *
3627  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3628  *	asynchronous errors should be reported by getsockopt. We assume
3629  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3630  */
3631 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3632 			   char __user *optval, int __user *optlen)
3633 {
3634 	struct sock *sk = sock->sk;
3635 
3636 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3637 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3638 }
3639 EXPORT_SYMBOL(sock_common_getsockopt);
3640 
3641 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3642 			int flags)
3643 {
3644 	struct sock *sk = sock->sk;
3645 	int addr_len = 0;
3646 	int err;
3647 
3648 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3649 	if (err >= 0)
3650 		msg->msg_namelen = addr_len;
3651 	return err;
3652 }
3653 EXPORT_SYMBOL(sock_common_recvmsg);
3654 
3655 /*
3656  *	Set socket options on an inet socket.
3657  */
3658 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3659 			   sockptr_t optval, unsigned int optlen)
3660 {
3661 	struct sock *sk = sock->sk;
3662 
3663 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3664 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3665 }
3666 EXPORT_SYMBOL(sock_common_setsockopt);
3667 
3668 void sk_common_release(struct sock *sk)
3669 {
3670 	if (sk->sk_prot->destroy)
3671 		sk->sk_prot->destroy(sk);
3672 
3673 	/*
3674 	 * Observation: when sk_common_release is called, processes have
3675 	 * no access to socket. But net still has.
3676 	 * Step one, detach it from networking:
3677 	 *
3678 	 * A. Remove from hash tables.
3679 	 */
3680 
3681 	sk->sk_prot->unhash(sk);
3682 
3683 	/*
3684 	 * In this point socket cannot receive new packets, but it is possible
3685 	 * that some packets are in flight because some CPU runs receiver and
3686 	 * did hash table lookup before we unhashed socket. They will achieve
3687 	 * receive queue and will be purged by socket destructor.
3688 	 *
3689 	 * Also we still have packets pending on receive queue and probably,
3690 	 * our own packets waiting in device queues. sock_destroy will drain
3691 	 * receive queue, but transmitted packets will delay socket destruction
3692 	 * until the last reference will be released.
3693 	 */
3694 
3695 	sock_orphan(sk);
3696 
3697 	xfrm_sk_free_policy(sk);
3698 
3699 	sk_refcnt_debug_release(sk);
3700 
3701 	sock_put(sk);
3702 }
3703 EXPORT_SYMBOL(sk_common_release);
3704 
3705 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3706 {
3707 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3708 
3709 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3710 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3711 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3712 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3713 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3714 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3715 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3716 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3717 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3718 }
3719 
3720 #ifdef CONFIG_PROC_FS
3721 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3722 
3723 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3724 {
3725 	int cpu, idx = prot->inuse_idx;
3726 	int res = 0;
3727 
3728 	for_each_possible_cpu(cpu)
3729 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3730 
3731 	return res >= 0 ? res : 0;
3732 }
3733 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3734 
3735 int sock_inuse_get(struct net *net)
3736 {
3737 	int cpu, res = 0;
3738 
3739 	for_each_possible_cpu(cpu)
3740 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3741 
3742 	return res;
3743 }
3744 
3745 EXPORT_SYMBOL_GPL(sock_inuse_get);
3746 
3747 static int __net_init sock_inuse_init_net(struct net *net)
3748 {
3749 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3750 	if (net->core.prot_inuse == NULL)
3751 		return -ENOMEM;
3752 	return 0;
3753 }
3754 
3755 static void __net_exit sock_inuse_exit_net(struct net *net)
3756 {
3757 	free_percpu(net->core.prot_inuse);
3758 }
3759 
3760 static struct pernet_operations net_inuse_ops = {
3761 	.init = sock_inuse_init_net,
3762 	.exit = sock_inuse_exit_net,
3763 };
3764 
3765 static __init int net_inuse_init(void)
3766 {
3767 	if (register_pernet_subsys(&net_inuse_ops))
3768 		panic("Cannot initialize net inuse counters");
3769 
3770 	return 0;
3771 }
3772 
3773 core_initcall(net_inuse_init);
3774 
3775 static int assign_proto_idx(struct proto *prot)
3776 {
3777 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3778 
3779 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3780 		pr_err("PROTO_INUSE_NR exhausted\n");
3781 		return -ENOSPC;
3782 	}
3783 
3784 	set_bit(prot->inuse_idx, proto_inuse_idx);
3785 	return 0;
3786 }
3787 
3788 static void release_proto_idx(struct proto *prot)
3789 {
3790 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3791 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3792 }
3793 #else
3794 static inline int assign_proto_idx(struct proto *prot)
3795 {
3796 	return 0;
3797 }
3798 
3799 static inline void release_proto_idx(struct proto *prot)
3800 {
3801 }
3802 
3803 #endif
3804 
3805 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3806 {
3807 	if (!twsk_prot)
3808 		return;
3809 	kfree(twsk_prot->twsk_slab_name);
3810 	twsk_prot->twsk_slab_name = NULL;
3811 	kmem_cache_destroy(twsk_prot->twsk_slab);
3812 	twsk_prot->twsk_slab = NULL;
3813 }
3814 
3815 static int tw_prot_init(const struct proto *prot)
3816 {
3817 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3818 
3819 	if (!twsk_prot)
3820 		return 0;
3821 
3822 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3823 					      prot->name);
3824 	if (!twsk_prot->twsk_slab_name)
3825 		return -ENOMEM;
3826 
3827 	twsk_prot->twsk_slab =
3828 		kmem_cache_create(twsk_prot->twsk_slab_name,
3829 				  twsk_prot->twsk_obj_size, 0,
3830 				  SLAB_ACCOUNT | prot->slab_flags,
3831 				  NULL);
3832 	if (!twsk_prot->twsk_slab) {
3833 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3834 			prot->name);
3835 		return -ENOMEM;
3836 	}
3837 
3838 	return 0;
3839 }
3840 
3841 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3842 {
3843 	if (!rsk_prot)
3844 		return;
3845 	kfree(rsk_prot->slab_name);
3846 	rsk_prot->slab_name = NULL;
3847 	kmem_cache_destroy(rsk_prot->slab);
3848 	rsk_prot->slab = NULL;
3849 }
3850 
3851 static int req_prot_init(const struct proto *prot)
3852 {
3853 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3854 
3855 	if (!rsk_prot)
3856 		return 0;
3857 
3858 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3859 					prot->name);
3860 	if (!rsk_prot->slab_name)
3861 		return -ENOMEM;
3862 
3863 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3864 					   rsk_prot->obj_size, 0,
3865 					   SLAB_ACCOUNT | prot->slab_flags,
3866 					   NULL);
3867 
3868 	if (!rsk_prot->slab) {
3869 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3870 			prot->name);
3871 		return -ENOMEM;
3872 	}
3873 	return 0;
3874 }
3875 
3876 int proto_register(struct proto *prot, int alloc_slab)
3877 {
3878 	int ret = -ENOBUFS;
3879 
3880 	if (prot->memory_allocated && !prot->sysctl_mem) {
3881 		pr_err("%s: missing sysctl_mem\n", prot->name);
3882 		return -EINVAL;
3883 	}
3884 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3885 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3886 		return -EINVAL;
3887 	}
3888 	if (alloc_slab) {
3889 		prot->slab = kmem_cache_create_usercopy(prot->name,
3890 					prot->obj_size, 0,
3891 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3892 					prot->slab_flags,
3893 					prot->useroffset, prot->usersize,
3894 					NULL);
3895 
3896 		if (prot->slab == NULL) {
3897 			pr_crit("%s: Can't create sock SLAB cache!\n",
3898 				prot->name);
3899 			goto out;
3900 		}
3901 
3902 		if (req_prot_init(prot))
3903 			goto out_free_request_sock_slab;
3904 
3905 		if (tw_prot_init(prot))
3906 			goto out_free_timewait_sock_slab;
3907 	}
3908 
3909 	mutex_lock(&proto_list_mutex);
3910 	ret = assign_proto_idx(prot);
3911 	if (ret) {
3912 		mutex_unlock(&proto_list_mutex);
3913 		goto out_free_timewait_sock_slab;
3914 	}
3915 	list_add(&prot->node, &proto_list);
3916 	mutex_unlock(&proto_list_mutex);
3917 	return ret;
3918 
3919 out_free_timewait_sock_slab:
3920 	if (alloc_slab)
3921 		tw_prot_cleanup(prot->twsk_prot);
3922 out_free_request_sock_slab:
3923 	if (alloc_slab) {
3924 		req_prot_cleanup(prot->rsk_prot);
3925 
3926 		kmem_cache_destroy(prot->slab);
3927 		prot->slab = NULL;
3928 	}
3929 out:
3930 	return ret;
3931 }
3932 EXPORT_SYMBOL(proto_register);
3933 
3934 void proto_unregister(struct proto *prot)
3935 {
3936 	mutex_lock(&proto_list_mutex);
3937 	release_proto_idx(prot);
3938 	list_del(&prot->node);
3939 	mutex_unlock(&proto_list_mutex);
3940 
3941 	kmem_cache_destroy(prot->slab);
3942 	prot->slab = NULL;
3943 
3944 	req_prot_cleanup(prot->rsk_prot);
3945 	tw_prot_cleanup(prot->twsk_prot);
3946 }
3947 EXPORT_SYMBOL(proto_unregister);
3948 
3949 int sock_load_diag_module(int family, int protocol)
3950 {
3951 	if (!protocol) {
3952 		if (!sock_is_registered(family))
3953 			return -ENOENT;
3954 
3955 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3956 				      NETLINK_SOCK_DIAG, family);
3957 	}
3958 
3959 #ifdef CONFIG_INET
3960 	if (family == AF_INET &&
3961 	    protocol != IPPROTO_RAW &&
3962 	    protocol < MAX_INET_PROTOS &&
3963 	    !rcu_access_pointer(inet_protos[protocol]))
3964 		return -ENOENT;
3965 #endif
3966 
3967 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3968 			      NETLINK_SOCK_DIAG, family, protocol);
3969 }
3970 EXPORT_SYMBOL(sock_load_diag_module);
3971 
3972 #ifdef CONFIG_PROC_FS
3973 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3974 	__acquires(proto_list_mutex)
3975 {
3976 	mutex_lock(&proto_list_mutex);
3977 	return seq_list_start_head(&proto_list, *pos);
3978 }
3979 
3980 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3981 {
3982 	return seq_list_next(v, &proto_list, pos);
3983 }
3984 
3985 static void proto_seq_stop(struct seq_file *seq, void *v)
3986 	__releases(proto_list_mutex)
3987 {
3988 	mutex_unlock(&proto_list_mutex);
3989 }
3990 
3991 static char proto_method_implemented(const void *method)
3992 {
3993 	return method == NULL ? 'n' : 'y';
3994 }
3995 static long sock_prot_memory_allocated(struct proto *proto)
3996 {
3997 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3998 }
3999 
4000 static const char *sock_prot_memory_pressure(struct proto *proto)
4001 {
4002 	return proto->memory_pressure != NULL ?
4003 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4004 }
4005 
4006 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4007 {
4008 
4009 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4010 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4011 		   proto->name,
4012 		   proto->obj_size,
4013 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4014 		   sock_prot_memory_allocated(proto),
4015 		   sock_prot_memory_pressure(proto),
4016 		   proto->max_header,
4017 		   proto->slab == NULL ? "no" : "yes",
4018 		   module_name(proto->owner),
4019 		   proto_method_implemented(proto->close),
4020 		   proto_method_implemented(proto->connect),
4021 		   proto_method_implemented(proto->disconnect),
4022 		   proto_method_implemented(proto->accept),
4023 		   proto_method_implemented(proto->ioctl),
4024 		   proto_method_implemented(proto->init),
4025 		   proto_method_implemented(proto->destroy),
4026 		   proto_method_implemented(proto->shutdown),
4027 		   proto_method_implemented(proto->setsockopt),
4028 		   proto_method_implemented(proto->getsockopt),
4029 		   proto_method_implemented(proto->sendmsg),
4030 		   proto_method_implemented(proto->recvmsg),
4031 		   proto_method_implemented(proto->sendpage),
4032 		   proto_method_implemented(proto->bind),
4033 		   proto_method_implemented(proto->backlog_rcv),
4034 		   proto_method_implemented(proto->hash),
4035 		   proto_method_implemented(proto->unhash),
4036 		   proto_method_implemented(proto->get_port),
4037 		   proto_method_implemented(proto->enter_memory_pressure));
4038 }
4039 
4040 static int proto_seq_show(struct seq_file *seq, void *v)
4041 {
4042 	if (v == &proto_list)
4043 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4044 			   "protocol",
4045 			   "size",
4046 			   "sockets",
4047 			   "memory",
4048 			   "press",
4049 			   "maxhdr",
4050 			   "slab",
4051 			   "module",
4052 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4053 	else
4054 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4055 	return 0;
4056 }
4057 
4058 static const struct seq_operations proto_seq_ops = {
4059 	.start  = proto_seq_start,
4060 	.next   = proto_seq_next,
4061 	.stop   = proto_seq_stop,
4062 	.show   = proto_seq_show,
4063 };
4064 
4065 static __net_init int proto_init_net(struct net *net)
4066 {
4067 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4068 			sizeof(struct seq_net_private)))
4069 		return -ENOMEM;
4070 
4071 	return 0;
4072 }
4073 
4074 static __net_exit void proto_exit_net(struct net *net)
4075 {
4076 	remove_proc_entry("protocols", net->proc_net);
4077 }
4078 
4079 
4080 static __net_initdata struct pernet_operations proto_net_ops = {
4081 	.init = proto_init_net,
4082 	.exit = proto_exit_net,
4083 };
4084 
4085 static int __init proto_init(void)
4086 {
4087 	return register_pernet_subsys(&proto_net_ops);
4088 }
4089 
4090 subsys_initcall(proto_init);
4091 
4092 #endif /* PROC_FS */
4093 
4094 #ifdef CONFIG_NET_RX_BUSY_POLL
4095 bool sk_busy_loop_end(void *p, unsigned long start_time)
4096 {
4097 	struct sock *sk = p;
4098 
4099 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4100 	       sk_busy_loop_timeout(sk, start_time);
4101 }
4102 EXPORT_SYMBOL(sk_busy_loop_end);
4103 #endif /* CONFIG_NET_RX_BUSY_POLL */
4104 
4105 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4106 {
4107 	if (!sk->sk_prot->bind_add)
4108 		return -EOPNOTSUPP;
4109 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4110 }
4111 EXPORT_SYMBOL(sock_bind_add);
4112