xref: /openbmc/linux/net/core/sock.c (revision 022f19cf)
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 &&
905 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
906 		if (sk_is_tcp(sk)) {
907 			if ((1 << sk->sk_state) &
908 			    (TCPF_CLOSE | TCPF_LISTEN))
909 				return -EINVAL;
910 			atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
911 		} else {
912 			atomic_set(&sk->sk_tskey, 0);
913 		}
914 	}
915 
916 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
917 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
918 		return -EINVAL;
919 
920 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
921 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
922 		if (ret)
923 			return ret;
924 	}
925 
926 	sk->sk_tsflags = val;
927 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
928 
929 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
930 		sock_enable_timestamp(sk,
931 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
932 	else
933 		sock_disable_timestamp(sk,
934 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
935 	return 0;
936 }
937 
938 void sock_set_keepalive(struct sock *sk)
939 {
940 	lock_sock(sk);
941 	if (sk->sk_prot->keepalive)
942 		sk->sk_prot->keepalive(sk, true);
943 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
944 	release_sock(sk);
945 }
946 EXPORT_SYMBOL(sock_set_keepalive);
947 
948 static void __sock_set_rcvbuf(struct sock *sk, int val)
949 {
950 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
951 	 * as a negative value.
952 	 */
953 	val = min_t(int, val, INT_MAX / 2);
954 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
955 
956 	/* We double it on the way in to account for "struct sk_buff" etc.
957 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
958 	 * will allow that much actual data to be received on that socket.
959 	 *
960 	 * Applications are unaware that "struct sk_buff" and other overheads
961 	 * allocate from the receive buffer during socket buffer allocation.
962 	 *
963 	 * And after considering the possible alternatives, returning the value
964 	 * we actually used in getsockopt is the most desirable behavior.
965 	 */
966 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
967 }
968 
969 void sock_set_rcvbuf(struct sock *sk, int val)
970 {
971 	lock_sock(sk);
972 	__sock_set_rcvbuf(sk, val);
973 	release_sock(sk);
974 }
975 EXPORT_SYMBOL(sock_set_rcvbuf);
976 
977 static void __sock_set_mark(struct sock *sk, u32 val)
978 {
979 	if (val != sk->sk_mark) {
980 		sk->sk_mark = val;
981 		sk_dst_reset(sk);
982 	}
983 }
984 
985 void sock_set_mark(struct sock *sk, u32 val)
986 {
987 	lock_sock(sk);
988 	__sock_set_mark(sk, val);
989 	release_sock(sk);
990 }
991 EXPORT_SYMBOL(sock_set_mark);
992 
993 static void sock_release_reserved_memory(struct sock *sk, int bytes)
994 {
995 	/* Round down bytes to multiple of pages */
996 	bytes = round_down(bytes, PAGE_SIZE);
997 
998 	WARN_ON(bytes > sk->sk_reserved_mem);
999 	sk->sk_reserved_mem -= bytes;
1000 	sk_mem_reclaim(sk);
1001 }
1002 
1003 static int sock_reserve_memory(struct sock *sk, int bytes)
1004 {
1005 	long allocated;
1006 	bool charged;
1007 	int pages;
1008 
1009 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1010 		return -EOPNOTSUPP;
1011 
1012 	if (!bytes)
1013 		return 0;
1014 
1015 	pages = sk_mem_pages(bytes);
1016 
1017 	/* pre-charge to memcg */
1018 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1019 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1020 	if (!charged)
1021 		return -ENOMEM;
1022 
1023 	/* pre-charge to forward_alloc */
1024 	sk_memory_allocated_add(sk, pages);
1025 	allocated = sk_memory_allocated(sk);
1026 	/* If the system goes into memory pressure with this
1027 	 * precharge, give up and return error.
1028 	 */
1029 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1030 		sk_memory_allocated_sub(sk, pages);
1031 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1032 		return -ENOMEM;
1033 	}
1034 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1035 
1036 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1037 
1038 	return 0;
1039 }
1040 
1041 void sockopt_lock_sock(struct sock *sk)
1042 {
1043 	/* When current->bpf_ctx is set, the setsockopt is called from
1044 	 * a bpf prog.  bpf has ensured the sk lock has been
1045 	 * acquired before calling setsockopt().
1046 	 */
1047 	if (has_current_bpf_ctx())
1048 		return;
1049 
1050 	lock_sock(sk);
1051 }
1052 EXPORT_SYMBOL(sockopt_lock_sock);
1053 
1054 void sockopt_release_sock(struct sock *sk)
1055 {
1056 	if (has_current_bpf_ctx())
1057 		return;
1058 
1059 	release_sock(sk);
1060 }
1061 EXPORT_SYMBOL(sockopt_release_sock);
1062 
1063 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1064 {
1065 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1066 }
1067 EXPORT_SYMBOL(sockopt_ns_capable);
1068 
1069 bool sockopt_capable(int cap)
1070 {
1071 	return has_current_bpf_ctx() || capable(cap);
1072 }
1073 EXPORT_SYMBOL(sockopt_capable);
1074 
1075 /*
1076  *	This is meant for all protocols to use and covers goings on
1077  *	at the socket level. Everything here is generic.
1078  */
1079 
1080 int sk_setsockopt(struct sock *sk, int level, int optname,
1081 		  sockptr_t optval, unsigned int optlen)
1082 {
1083 	struct so_timestamping timestamping;
1084 	struct socket *sock = sk->sk_socket;
1085 	struct sock_txtime sk_txtime;
1086 	int val;
1087 	int valbool;
1088 	struct linger ling;
1089 	int ret = 0;
1090 
1091 	/*
1092 	 *	Options without arguments
1093 	 */
1094 
1095 	if (optname == SO_BINDTODEVICE)
1096 		return sock_setbindtodevice(sk, optval, optlen);
1097 
1098 	if (optlen < sizeof(int))
1099 		return -EINVAL;
1100 
1101 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1102 		return -EFAULT;
1103 
1104 	valbool = val ? 1 : 0;
1105 
1106 	sockopt_lock_sock(sk);
1107 
1108 	switch (optname) {
1109 	case SO_DEBUG:
1110 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1111 			ret = -EACCES;
1112 		else
1113 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1114 		break;
1115 	case SO_REUSEADDR:
1116 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1117 		break;
1118 	case SO_REUSEPORT:
1119 		sk->sk_reuseport = valbool;
1120 		break;
1121 	case SO_TYPE:
1122 	case SO_PROTOCOL:
1123 	case SO_DOMAIN:
1124 	case SO_ERROR:
1125 		ret = -ENOPROTOOPT;
1126 		break;
1127 	case SO_DONTROUTE:
1128 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1129 		sk_dst_reset(sk);
1130 		break;
1131 	case SO_BROADCAST:
1132 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1133 		break;
1134 	case SO_SNDBUF:
1135 		/* Don't error on this BSD doesn't and if you think
1136 		 * about it this is right. Otherwise apps have to
1137 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1138 		 * are treated in BSD as hints
1139 		 */
1140 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1141 set_sndbuf:
1142 		/* Ensure val * 2 fits into an int, to prevent max_t()
1143 		 * from treating it as a negative value.
1144 		 */
1145 		val = min_t(int, val, INT_MAX / 2);
1146 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1147 		WRITE_ONCE(sk->sk_sndbuf,
1148 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1149 		/* Wake up sending tasks if we upped the value. */
1150 		sk->sk_write_space(sk);
1151 		break;
1152 
1153 	case SO_SNDBUFFORCE:
1154 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1155 			ret = -EPERM;
1156 			break;
1157 		}
1158 
1159 		/* No negative values (to prevent underflow, as val will be
1160 		 * multiplied by 2).
1161 		 */
1162 		if (val < 0)
1163 			val = 0;
1164 		goto set_sndbuf;
1165 
1166 	case SO_RCVBUF:
1167 		/* Don't error on this BSD doesn't and if you think
1168 		 * about it this is right. Otherwise apps have to
1169 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1170 		 * are treated in BSD as hints
1171 		 */
1172 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1173 		break;
1174 
1175 	case SO_RCVBUFFORCE:
1176 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1177 			ret = -EPERM;
1178 			break;
1179 		}
1180 
1181 		/* No negative values (to prevent underflow, as val will be
1182 		 * multiplied by 2).
1183 		 */
1184 		__sock_set_rcvbuf(sk, max(val, 0));
1185 		break;
1186 
1187 	case SO_KEEPALIVE:
1188 		if (sk->sk_prot->keepalive)
1189 			sk->sk_prot->keepalive(sk, valbool);
1190 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1191 		break;
1192 
1193 	case SO_OOBINLINE:
1194 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1195 		break;
1196 
1197 	case SO_NO_CHECK:
1198 		sk->sk_no_check_tx = valbool;
1199 		break;
1200 
1201 	case SO_PRIORITY:
1202 		if ((val >= 0 && val <= 6) ||
1203 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1204 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1205 			sk->sk_priority = val;
1206 		else
1207 			ret = -EPERM;
1208 		break;
1209 
1210 	case SO_LINGER:
1211 		if (optlen < sizeof(ling)) {
1212 			ret = -EINVAL;	/* 1003.1g */
1213 			break;
1214 		}
1215 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1216 			ret = -EFAULT;
1217 			break;
1218 		}
1219 		if (!ling.l_onoff)
1220 			sock_reset_flag(sk, SOCK_LINGER);
1221 		else {
1222 #if (BITS_PER_LONG == 32)
1223 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1224 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1225 			else
1226 #endif
1227 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1228 			sock_set_flag(sk, SOCK_LINGER);
1229 		}
1230 		break;
1231 
1232 	case SO_BSDCOMPAT:
1233 		break;
1234 
1235 	case SO_PASSCRED:
1236 		if (valbool)
1237 			set_bit(SOCK_PASSCRED, &sock->flags);
1238 		else
1239 			clear_bit(SOCK_PASSCRED, &sock->flags);
1240 		break;
1241 
1242 	case SO_TIMESTAMP_OLD:
1243 	case SO_TIMESTAMP_NEW:
1244 	case SO_TIMESTAMPNS_OLD:
1245 	case SO_TIMESTAMPNS_NEW:
1246 		sock_set_timestamp(sk, optname, valbool);
1247 		break;
1248 
1249 	case SO_TIMESTAMPING_NEW:
1250 	case SO_TIMESTAMPING_OLD:
1251 		if (optlen == sizeof(timestamping)) {
1252 			if (copy_from_sockptr(&timestamping, optval,
1253 					      sizeof(timestamping))) {
1254 				ret = -EFAULT;
1255 				break;
1256 			}
1257 		} else {
1258 			memset(&timestamping, 0, sizeof(timestamping));
1259 			timestamping.flags = val;
1260 		}
1261 		ret = sock_set_timestamping(sk, optname, timestamping);
1262 		break;
1263 
1264 	case SO_RCVLOWAT:
1265 		if (val < 0)
1266 			val = INT_MAX;
1267 		if (sock && sock->ops->set_rcvlowat)
1268 			ret = sock->ops->set_rcvlowat(sk, val);
1269 		else
1270 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1271 		break;
1272 
1273 	case SO_RCVTIMEO_OLD:
1274 	case SO_RCVTIMEO_NEW:
1275 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1276 				       optlen, optname == SO_RCVTIMEO_OLD);
1277 		break;
1278 
1279 	case SO_SNDTIMEO_OLD:
1280 	case SO_SNDTIMEO_NEW:
1281 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1282 				       optlen, optname == SO_SNDTIMEO_OLD);
1283 		break;
1284 
1285 	case SO_ATTACH_FILTER: {
1286 		struct sock_fprog fprog;
1287 
1288 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1289 		if (!ret)
1290 			ret = sk_attach_filter(&fprog, sk);
1291 		break;
1292 	}
1293 	case SO_ATTACH_BPF:
1294 		ret = -EINVAL;
1295 		if (optlen == sizeof(u32)) {
1296 			u32 ufd;
1297 
1298 			ret = -EFAULT;
1299 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1300 				break;
1301 
1302 			ret = sk_attach_bpf(ufd, sk);
1303 		}
1304 		break;
1305 
1306 	case SO_ATTACH_REUSEPORT_CBPF: {
1307 		struct sock_fprog fprog;
1308 
1309 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1310 		if (!ret)
1311 			ret = sk_reuseport_attach_filter(&fprog, sk);
1312 		break;
1313 	}
1314 	case SO_ATTACH_REUSEPORT_EBPF:
1315 		ret = -EINVAL;
1316 		if (optlen == sizeof(u32)) {
1317 			u32 ufd;
1318 
1319 			ret = -EFAULT;
1320 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1321 				break;
1322 
1323 			ret = sk_reuseport_attach_bpf(ufd, sk);
1324 		}
1325 		break;
1326 
1327 	case SO_DETACH_REUSEPORT_BPF:
1328 		ret = reuseport_detach_prog(sk);
1329 		break;
1330 
1331 	case SO_DETACH_FILTER:
1332 		ret = sk_detach_filter(sk);
1333 		break;
1334 
1335 	case SO_LOCK_FILTER:
1336 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1337 			ret = -EPERM;
1338 		else
1339 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1340 		break;
1341 
1342 	case SO_PASSSEC:
1343 		if (valbool)
1344 			set_bit(SOCK_PASSSEC, &sock->flags);
1345 		else
1346 			clear_bit(SOCK_PASSSEC, &sock->flags);
1347 		break;
1348 	case SO_MARK:
1349 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1350 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1351 			ret = -EPERM;
1352 			break;
1353 		}
1354 
1355 		__sock_set_mark(sk, val);
1356 		break;
1357 	case SO_RCVMARK:
1358 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1359 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1360 			ret = -EPERM;
1361 			break;
1362 		}
1363 
1364 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1365 		break;
1366 
1367 	case SO_RXQ_OVFL:
1368 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1369 		break;
1370 
1371 	case SO_WIFI_STATUS:
1372 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1373 		break;
1374 
1375 	case SO_PEEK_OFF:
1376 		if (sock->ops->set_peek_off)
1377 			ret = sock->ops->set_peek_off(sk, val);
1378 		else
1379 			ret = -EOPNOTSUPP;
1380 		break;
1381 
1382 	case SO_NOFCS:
1383 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1384 		break;
1385 
1386 	case SO_SELECT_ERR_QUEUE:
1387 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1388 		break;
1389 
1390 #ifdef CONFIG_NET_RX_BUSY_POLL
1391 	case SO_BUSY_POLL:
1392 		/* allow unprivileged users to decrease the value */
1393 		if ((val > sk->sk_ll_usec) && !sockopt_capable(CAP_NET_ADMIN))
1394 			ret = -EPERM;
1395 		else {
1396 			if (val < 0)
1397 				ret = -EINVAL;
1398 			else
1399 				WRITE_ONCE(sk->sk_ll_usec, val);
1400 		}
1401 		break;
1402 	case SO_PREFER_BUSY_POLL:
1403 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1404 			ret = -EPERM;
1405 		else
1406 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1407 		break;
1408 	case SO_BUSY_POLL_BUDGET:
1409 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1410 			ret = -EPERM;
1411 		} else {
1412 			if (val < 0 || val > U16_MAX)
1413 				ret = -EINVAL;
1414 			else
1415 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1416 		}
1417 		break;
1418 #endif
1419 
1420 	case SO_MAX_PACING_RATE:
1421 		{
1422 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1423 
1424 		if (sizeof(ulval) != sizeof(val) &&
1425 		    optlen >= sizeof(ulval) &&
1426 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1427 			ret = -EFAULT;
1428 			break;
1429 		}
1430 		if (ulval != ~0UL)
1431 			cmpxchg(&sk->sk_pacing_status,
1432 				SK_PACING_NONE,
1433 				SK_PACING_NEEDED);
1434 		sk->sk_max_pacing_rate = ulval;
1435 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1436 		break;
1437 		}
1438 	case SO_INCOMING_CPU:
1439 		reuseport_update_incoming_cpu(sk, val);
1440 		break;
1441 
1442 	case SO_CNX_ADVICE:
1443 		if (val == 1)
1444 			dst_negative_advice(sk);
1445 		break;
1446 
1447 	case SO_ZEROCOPY:
1448 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1449 			if (!(sk_is_tcp(sk) ||
1450 			      (sk->sk_type == SOCK_DGRAM &&
1451 			       sk->sk_protocol == IPPROTO_UDP)))
1452 				ret = -EOPNOTSUPP;
1453 		} else if (sk->sk_family != PF_RDS) {
1454 			ret = -EOPNOTSUPP;
1455 		}
1456 		if (!ret) {
1457 			if (val < 0 || val > 1)
1458 				ret = -EINVAL;
1459 			else
1460 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1461 		}
1462 		break;
1463 
1464 	case SO_TXTIME:
1465 		if (optlen != sizeof(struct sock_txtime)) {
1466 			ret = -EINVAL;
1467 			break;
1468 		} else if (copy_from_sockptr(&sk_txtime, optval,
1469 			   sizeof(struct sock_txtime))) {
1470 			ret = -EFAULT;
1471 			break;
1472 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1473 			ret = -EINVAL;
1474 			break;
1475 		}
1476 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1477 		 * scheduler has enough safe guards.
1478 		 */
1479 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1480 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1481 			ret = -EPERM;
1482 			break;
1483 		}
1484 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1485 		sk->sk_clockid = sk_txtime.clockid;
1486 		sk->sk_txtime_deadline_mode =
1487 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1488 		sk->sk_txtime_report_errors =
1489 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1490 		break;
1491 
1492 	case SO_BINDTOIFINDEX:
1493 		ret = sock_bindtoindex_locked(sk, val);
1494 		break;
1495 
1496 	case SO_BUF_LOCK:
1497 		if (val & ~SOCK_BUF_LOCK_MASK) {
1498 			ret = -EINVAL;
1499 			break;
1500 		}
1501 		sk->sk_userlocks = val | (sk->sk_userlocks &
1502 					  ~SOCK_BUF_LOCK_MASK);
1503 		break;
1504 
1505 	case SO_RESERVE_MEM:
1506 	{
1507 		int delta;
1508 
1509 		if (val < 0) {
1510 			ret = -EINVAL;
1511 			break;
1512 		}
1513 
1514 		delta = val - sk->sk_reserved_mem;
1515 		if (delta < 0)
1516 			sock_release_reserved_memory(sk, -delta);
1517 		else
1518 			ret = sock_reserve_memory(sk, delta);
1519 		break;
1520 	}
1521 
1522 	case SO_TXREHASH:
1523 		if (val < -1 || val > 1) {
1524 			ret = -EINVAL;
1525 			break;
1526 		}
1527 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1528 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1529 		break;
1530 
1531 	default:
1532 		ret = -ENOPROTOOPT;
1533 		break;
1534 	}
1535 	sockopt_release_sock(sk);
1536 	return ret;
1537 }
1538 
1539 int sock_setsockopt(struct socket *sock, int level, int optname,
1540 		    sockptr_t optval, unsigned int optlen)
1541 {
1542 	return sk_setsockopt(sock->sk, level, optname,
1543 			     optval, optlen);
1544 }
1545 EXPORT_SYMBOL(sock_setsockopt);
1546 
1547 static const struct cred *sk_get_peer_cred(struct sock *sk)
1548 {
1549 	const struct cred *cred;
1550 
1551 	spin_lock(&sk->sk_peer_lock);
1552 	cred = get_cred(sk->sk_peer_cred);
1553 	spin_unlock(&sk->sk_peer_lock);
1554 
1555 	return cred;
1556 }
1557 
1558 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1559 			  struct ucred *ucred)
1560 {
1561 	ucred->pid = pid_vnr(pid);
1562 	ucred->uid = ucred->gid = -1;
1563 	if (cred) {
1564 		struct user_namespace *current_ns = current_user_ns();
1565 
1566 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1567 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1568 	}
1569 }
1570 
1571 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1572 {
1573 	struct user_namespace *user_ns = current_user_ns();
1574 	int i;
1575 
1576 	for (i = 0; i < src->ngroups; i++) {
1577 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1578 
1579 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1580 			return -EFAULT;
1581 	}
1582 
1583 	return 0;
1584 }
1585 
1586 int sk_getsockopt(struct sock *sk, int level, int optname,
1587 		  sockptr_t optval, sockptr_t optlen)
1588 {
1589 	struct socket *sock = sk->sk_socket;
1590 
1591 	union {
1592 		int val;
1593 		u64 val64;
1594 		unsigned long ulval;
1595 		struct linger ling;
1596 		struct old_timeval32 tm32;
1597 		struct __kernel_old_timeval tm;
1598 		struct  __kernel_sock_timeval stm;
1599 		struct sock_txtime txtime;
1600 		struct so_timestamping timestamping;
1601 	} v;
1602 
1603 	int lv = sizeof(int);
1604 	int len;
1605 
1606 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1607 		return -EFAULT;
1608 	if (len < 0)
1609 		return -EINVAL;
1610 
1611 	memset(&v, 0, sizeof(v));
1612 
1613 	switch (optname) {
1614 	case SO_DEBUG:
1615 		v.val = sock_flag(sk, SOCK_DBG);
1616 		break;
1617 
1618 	case SO_DONTROUTE:
1619 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1620 		break;
1621 
1622 	case SO_BROADCAST:
1623 		v.val = sock_flag(sk, SOCK_BROADCAST);
1624 		break;
1625 
1626 	case SO_SNDBUF:
1627 		v.val = sk->sk_sndbuf;
1628 		break;
1629 
1630 	case SO_RCVBUF:
1631 		v.val = sk->sk_rcvbuf;
1632 		break;
1633 
1634 	case SO_REUSEADDR:
1635 		v.val = sk->sk_reuse;
1636 		break;
1637 
1638 	case SO_REUSEPORT:
1639 		v.val = sk->sk_reuseport;
1640 		break;
1641 
1642 	case SO_KEEPALIVE:
1643 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1644 		break;
1645 
1646 	case SO_TYPE:
1647 		v.val = sk->sk_type;
1648 		break;
1649 
1650 	case SO_PROTOCOL:
1651 		v.val = sk->sk_protocol;
1652 		break;
1653 
1654 	case SO_DOMAIN:
1655 		v.val = sk->sk_family;
1656 		break;
1657 
1658 	case SO_ERROR:
1659 		v.val = -sock_error(sk);
1660 		if (v.val == 0)
1661 			v.val = xchg(&sk->sk_err_soft, 0);
1662 		break;
1663 
1664 	case SO_OOBINLINE:
1665 		v.val = sock_flag(sk, SOCK_URGINLINE);
1666 		break;
1667 
1668 	case SO_NO_CHECK:
1669 		v.val = sk->sk_no_check_tx;
1670 		break;
1671 
1672 	case SO_PRIORITY:
1673 		v.val = sk->sk_priority;
1674 		break;
1675 
1676 	case SO_LINGER:
1677 		lv		= sizeof(v.ling);
1678 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1679 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1680 		break;
1681 
1682 	case SO_BSDCOMPAT:
1683 		break;
1684 
1685 	case SO_TIMESTAMP_OLD:
1686 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1687 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1688 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1689 		break;
1690 
1691 	case SO_TIMESTAMPNS_OLD:
1692 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1693 		break;
1694 
1695 	case SO_TIMESTAMP_NEW:
1696 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1697 		break;
1698 
1699 	case SO_TIMESTAMPNS_NEW:
1700 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1701 		break;
1702 
1703 	case SO_TIMESTAMPING_OLD:
1704 		lv = sizeof(v.timestamping);
1705 		v.timestamping.flags = sk->sk_tsflags;
1706 		v.timestamping.bind_phc = sk->sk_bind_phc;
1707 		break;
1708 
1709 	case SO_RCVTIMEO_OLD:
1710 	case SO_RCVTIMEO_NEW:
1711 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1712 		break;
1713 
1714 	case SO_SNDTIMEO_OLD:
1715 	case SO_SNDTIMEO_NEW:
1716 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1717 		break;
1718 
1719 	case SO_RCVLOWAT:
1720 		v.val = sk->sk_rcvlowat;
1721 		break;
1722 
1723 	case SO_SNDLOWAT:
1724 		v.val = 1;
1725 		break;
1726 
1727 	case SO_PASSCRED:
1728 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1729 		break;
1730 
1731 	case SO_PEERCRED:
1732 	{
1733 		struct ucred peercred;
1734 		if (len > sizeof(peercred))
1735 			len = sizeof(peercred);
1736 
1737 		spin_lock(&sk->sk_peer_lock);
1738 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1739 		spin_unlock(&sk->sk_peer_lock);
1740 
1741 		if (copy_to_sockptr(optval, &peercred, len))
1742 			return -EFAULT;
1743 		goto lenout;
1744 	}
1745 
1746 	case SO_PEERGROUPS:
1747 	{
1748 		const struct cred *cred;
1749 		int ret, n;
1750 
1751 		cred = sk_get_peer_cred(sk);
1752 		if (!cred)
1753 			return -ENODATA;
1754 
1755 		n = cred->group_info->ngroups;
1756 		if (len < n * sizeof(gid_t)) {
1757 			len = n * sizeof(gid_t);
1758 			put_cred(cred);
1759 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1760 		}
1761 		len = n * sizeof(gid_t);
1762 
1763 		ret = groups_to_user(optval, cred->group_info);
1764 		put_cred(cred);
1765 		if (ret)
1766 			return ret;
1767 		goto lenout;
1768 	}
1769 
1770 	case SO_PEERNAME:
1771 	{
1772 		char address[128];
1773 
1774 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1775 		if (lv < 0)
1776 			return -ENOTCONN;
1777 		if (lv < len)
1778 			return -EINVAL;
1779 		if (copy_to_sockptr(optval, address, len))
1780 			return -EFAULT;
1781 		goto lenout;
1782 	}
1783 
1784 	/* Dubious BSD thing... Probably nobody even uses it, but
1785 	 * the UNIX standard wants it for whatever reason... -DaveM
1786 	 */
1787 	case SO_ACCEPTCONN:
1788 		v.val = sk->sk_state == TCP_LISTEN;
1789 		break;
1790 
1791 	case SO_PASSSEC:
1792 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1793 		break;
1794 
1795 	case SO_PEERSEC:
1796 		return security_socket_getpeersec_stream(sock, optval.user, optlen.user, len);
1797 
1798 	case SO_MARK:
1799 		v.val = sk->sk_mark;
1800 		break;
1801 
1802 	case SO_RCVMARK:
1803 		v.val = sock_flag(sk, SOCK_RCVMARK);
1804 		break;
1805 
1806 	case SO_RXQ_OVFL:
1807 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1808 		break;
1809 
1810 	case SO_WIFI_STATUS:
1811 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1812 		break;
1813 
1814 	case SO_PEEK_OFF:
1815 		if (!sock->ops->set_peek_off)
1816 			return -EOPNOTSUPP;
1817 
1818 		v.val = sk->sk_peek_off;
1819 		break;
1820 	case SO_NOFCS:
1821 		v.val = sock_flag(sk, SOCK_NOFCS);
1822 		break;
1823 
1824 	case SO_BINDTODEVICE:
1825 		return sock_getbindtodevice(sk, optval, optlen, len);
1826 
1827 	case SO_GET_FILTER:
1828 		len = sk_get_filter(sk, optval, len);
1829 		if (len < 0)
1830 			return len;
1831 
1832 		goto lenout;
1833 
1834 	case SO_LOCK_FILTER:
1835 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1836 		break;
1837 
1838 	case SO_BPF_EXTENSIONS:
1839 		v.val = bpf_tell_extensions();
1840 		break;
1841 
1842 	case SO_SELECT_ERR_QUEUE:
1843 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1844 		break;
1845 
1846 #ifdef CONFIG_NET_RX_BUSY_POLL
1847 	case SO_BUSY_POLL:
1848 		v.val = sk->sk_ll_usec;
1849 		break;
1850 	case SO_PREFER_BUSY_POLL:
1851 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1852 		break;
1853 #endif
1854 
1855 	case SO_MAX_PACING_RATE:
1856 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1857 			lv = sizeof(v.ulval);
1858 			v.ulval = sk->sk_max_pacing_rate;
1859 		} else {
1860 			/* 32bit version */
1861 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1862 		}
1863 		break;
1864 
1865 	case SO_INCOMING_CPU:
1866 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1867 		break;
1868 
1869 	case SO_MEMINFO:
1870 	{
1871 		u32 meminfo[SK_MEMINFO_VARS];
1872 
1873 		sk_get_meminfo(sk, meminfo);
1874 
1875 		len = min_t(unsigned int, len, sizeof(meminfo));
1876 		if (copy_to_sockptr(optval, &meminfo, len))
1877 			return -EFAULT;
1878 
1879 		goto lenout;
1880 	}
1881 
1882 #ifdef CONFIG_NET_RX_BUSY_POLL
1883 	case SO_INCOMING_NAPI_ID:
1884 		v.val = READ_ONCE(sk->sk_napi_id);
1885 
1886 		/* aggregate non-NAPI IDs down to 0 */
1887 		if (v.val < MIN_NAPI_ID)
1888 			v.val = 0;
1889 
1890 		break;
1891 #endif
1892 
1893 	case SO_COOKIE:
1894 		lv = sizeof(u64);
1895 		if (len < lv)
1896 			return -EINVAL;
1897 		v.val64 = sock_gen_cookie(sk);
1898 		break;
1899 
1900 	case SO_ZEROCOPY:
1901 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1902 		break;
1903 
1904 	case SO_TXTIME:
1905 		lv = sizeof(v.txtime);
1906 		v.txtime.clockid = sk->sk_clockid;
1907 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1908 				  SOF_TXTIME_DEADLINE_MODE : 0;
1909 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1910 				  SOF_TXTIME_REPORT_ERRORS : 0;
1911 		break;
1912 
1913 	case SO_BINDTOIFINDEX:
1914 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1915 		break;
1916 
1917 	case SO_NETNS_COOKIE:
1918 		lv = sizeof(u64);
1919 		if (len != lv)
1920 			return -EINVAL;
1921 		v.val64 = sock_net(sk)->net_cookie;
1922 		break;
1923 
1924 	case SO_BUF_LOCK:
1925 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1926 		break;
1927 
1928 	case SO_RESERVE_MEM:
1929 		v.val = sk->sk_reserved_mem;
1930 		break;
1931 
1932 	case SO_TXREHASH:
1933 		v.val = sk->sk_txrehash;
1934 		break;
1935 
1936 	default:
1937 		/* We implement the SO_SNDLOWAT etc to not be settable
1938 		 * (1003.1g 7).
1939 		 */
1940 		return -ENOPROTOOPT;
1941 	}
1942 
1943 	if (len > lv)
1944 		len = lv;
1945 	if (copy_to_sockptr(optval, &v, len))
1946 		return -EFAULT;
1947 lenout:
1948 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1949 		return -EFAULT;
1950 	return 0;
1951 }
1952 
1953 int sock_getsockopt(struct socket *sock, int level, int optname,
1954 		    char __user *optval, int __user *optlen)
1955 {
1956 	return sk_getsockopt(sock->sk, level, optname,
1957 			     USER_SOCKPTR(optval),
1958 			     USER_SOCKPTR(optlen));
1959 }
1960 
1961 /*
1962  * Initialize an sk_lock.
1963  *
1964  * (We also register the sk_lock with the lock validator.)
1965  */
1966 static inline void sock_lock_init(struct sock *sk)
1967 {
1968 	if (sk->sk_kern_sock)
1969 		sock_lock_init_class_and_name(
1970 			sk,
1971 			af_family_kern_slock_key_strings[sk->sk_family],
1972 			af_family_kern_slock_keys + sk->sk_family,
1973 			af_family_kern_key_strings[sk->sk_family],
1974 			af_family_kern_keys + sk->sk_family);
1975 	else
1976 		sock_lock_init_class_and_name(
1977 			sk,
1978 			af_family_slock_key_strings[sk->sk_family],
1979 			af_family_slock_keys + sk->sk_family,
1980 			af_family_key_strings[sk->sk_family],
1981 			af_family_keys + sk->sk_family);
1982 }
1983 
1984 /*
1985  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1986  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1987  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1988  */
1989 static void sock_copy(struct sock *nsk, const struct sock *osk)
1990 {
1991 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1992 #ifdef CONFIG_SECURITY_NETWORK
1993 	void *sptr = nsk->sk_security;
1994 #endif
1995 
1996 	/* If we move sk_tx_queue_mapping out of the private section,
1997 	 * we must check if sk_tx_queue_clear() is called after
1998 	 * sock_copy() in sk_clone_lock().
1999 	 */
2000 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2001 		     offsetof(struct sock, sk_dontcopy_begin) ||
2002 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2003 		     offsetof(struct sock, sk_dontcopy_end));
2004 
2005 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2006 
2007 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2008 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2009 
2010 #ifdef CONFIG_SECURITY_NETWORK
2011 	nsk->sk_security = sptr;
2012 	security_sk_clone(osk, nsk);
2013 #endif
2014 }
2015 
2016 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2017 		int family)
2018 {
2019 	struct sock *sk;
2020 	struct kmem_cache *slab;
2021 
2022 	slab = prot->slab;
2023 	if (slab != NULL) {
2024 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2025 		if (!sk)
2026 			return sk;
2027 		if (want_init_on_alloc(priority))
2028 			sk_prot_clear_nulls(sk, prot->obj_size);
2029 	} else
2030 		sk = kmalloc(prot->obj_size, priority);
2031 
2032 	if (sk != NULL) {
2033 		if (security_sk_alloc(sk, family, priority))
2034 			goto out_free;
2035 
2036 		if (!try_module_get(prot->owner))
2037 			goto out_free_sec;
2038 	}
2039 
2040 	return sk;
2041 
2042 out_free_sec:
2043 	security_sk_free(sk);
2044 out_free:
2045 	if (slab != NULL)
2046 		kmem_cache_free(slab, sk);
2047 	else
2048 		kfree(sk);
2049 	return NULL;
2050 }
2051 
2052 static void sk_prot_free(struct proto *prot, struct sock *sk)
2053 {
2054 	struct kmem_cache *slab;
2055 	struct module *owner;
2056 
2057 	owner = prot->owner;
2058 	slab = prot->slab;
2059 
2060 	cgroup_sk_free(&sk->sk_cgrp_data);
2061 	mem_cgroup_sk_free(sk);
2062 	security_sk_free(sk);
2063 	if (slab != NULL)
2064 		kmem_cache_free(slab, sk);
2065 	else
2066 		kfree(sk);
2067 	module_put(owner);
2068 }
2069 
2070 /**
2071  *	sk_alloc - All socket objects are allocated here
2072  *	@net: the applicable net namespace
2073  *	@family: protocol family
2074  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2075  *	@prot: struct proto associated with this new sock instance
2076  *	@kern: is this to be a kernel socket?
2077  */
2078 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2079 		      struct proto *prot, int kern)
2080 {
2081 	struct sock *sk;
2082 
2083 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2084 	if (sk) {
2085 		sk->sk_family = family;
2086 		/*
2087 		 * See comment in struct sock definition to understand
2088 		 * why we need sk_prot_creator -acme
2089 		 */
2090 		sk->sk_prot = sk->sk_prot_creator = prot;
2091 		sk->sk_kern_sock = kern;
2092 		sock_lock_init(sk);
2093 		sk->sk_net_refcnt = kern ? 0 : 1;
2094 		if (likely(sk->sk_net_refcnt)) {
2095 			get_net_track(net, &sk->ns_tracker, priority);
2096 			sock_inuse_add(net, 1);
2097 		} else {
2098 			__netns_tracker_alloc(net, &sk->ns_tracker,
2099 					      false, priority);
2100 		}
2101 
2102 		sock_net_set(sk, net);
2103 		refcount_set(&sk->sk_wmem_alloc, 1);
2104 
2105 		mem_cgroup_sk_alloc(sk);
2106 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2107 		sock_update_classid(&sk->sk_cgrp_data);
2108 		sock_update_netprioidx(&sk->sk_cgrp_data);
2109 		sk_tx_queue_clear(sk);
2110 	}
2111 
2112 	return sk;
2113 }
2114 EXPORT_SYMBOL(sk_alloc);
2115 
2116 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2117  * grace period. This is the case for UDP sockets and TCP listeners.
2118  */
2119 static void __sk_destruct(struct rcu_head *head)
2120 {
2121 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2122 	struct sk_filter *filter;
2123 
2124 	if (sk->sk_destruct)
2125 		sk->sk_destruct(sk);
2126 
2127 	filter = rcu_dereference_check(sk->sk_filter,
2128 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2129 	if (filter) {
2130 		sk_filter_uncharge(sk, filter);
2131 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2132 	}
2133 
2134 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2135 
2136 #ifdef CONFIG_BPF_SYSCALL
2137 	bpf_sk_storage_free(sk);
2138 #endif
2139 
2140 	if (atomic_read(&sk->sk_omem_alloc))
2141 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2142 			 __func__, atomic_read(&sk->sk_omem_alloc));
2143 
2144 	if (sk->sk_frag.page) {
2145 		put_page(sk->sk_frag.page);
2146 		sk->sk_frag.page = NULL;
2147 	}
2148 
2149 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2150 	put_cred(sk->sk_peer_cred);
2151 	put_pid(sk->sk_peer_pid);
2152 
2153 	if (likely(sk->sk_net_refcnt))
2154 		put_net_track(sock_net(sk), &sk->ns_tracker);
2155 	else
2156 		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2157 
2158 	sk_prot_free(sk->sk_prot_creator, sk);
2159 }
2160 
2161 void sk_destruct(struct sock *sk)
2162 {
2163 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2164 
2165 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2166 		reuseport_detach_sock(sk);
2167 		use_call_rcu = true;
2168 	}
2169 
2170 	if (use_call_rcu)
2171 		call_rcu(&sk->sk_rcu, __sk_destruct);
2172 	else
2173 		__sk_destruct(&sk->sk_rcu);
2174 }
2175 
2176 static void __sk_free(struct sock *sk)
2177 {
2178 	if (likely(sk->sk_net_refcnt))
2179 		sock_inuse_add(sock_net(sk), -1);
2180 
2181 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2182 		sock_diag_broadcast_destroy(sk);
2183 	else
2184 		sk_destruct(sk);
2185 }
2186 
2187 void sk_free(struct sock *sk)
2188 {
2189 	/*
2190 	 * We subtract one from sk_wmem_alloc and can know if
2191 	 * some packets are still in some tx queue.
2192 	 * If not null, sock_wfree() will call __sk_free(sk) later
2193 	 */
2194 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2195 		__sk_free(sk);
2196 }
2197 EXPORT_SYMBOL(sk_free);
2198 
2199 static void sk_init_common(struct sock *sk)
2200 {
2201 	skb_queue_head_init(&sk->sk_receive_queue);
2202 	skb_queue_head_init(&sk->sk_write_queue);
2203 	skb_queue_head_init(&sk->sk_error_queue);
2204 
2205 	rwlock_init(&sk->sk_callback_lock);
2206 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2207 			af_rlock_keys + sk->sk_family,
2208 			af_family_rlock_key_strings[sk->sk_family]);
2209 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2210 			af_wlock_keys + sk->sk_family,
2211 			af_family_wlock_key_strings[sk->sk_family]);
2212 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2213 			af_elock_keys + sk->sk_family,
2214 			af_family_elock_key_strings[sk->sk_family]);
2215 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2216 			af_callback_keys + sk->sk_family,
2217 			af_family_clock_key_strings[sk->sk_family]);
2218 }
2219 
2220 /**
2221  *	sk_clone_lock - clone a socket, and lock its clone
2222  *	@sk: the socket to clone
2223  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2224  *
2225  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2226  */
2227 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2228 {
2229 	struct proto *prot = READ_ONCE(sk->sk_prot);
2230 	struct sk_filter *filter;
2231 	bool is_charged = true;
2232 	struct sock *newsk;
2233 
2234 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2235 	if (!newsk)
2236 		goto out;
2237 
2238 	sock_copy(newsk, sk);
2239 
2240 	newsk->sk_prot_creator = prot;
2241 
2242 	/* SANITY */
2243 	if (likely(newsk->sk_net_refcnt)) {
2244 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2245 		sock_inuse_add(sock_net(newsk), 1);
2246 	} else {
2247 		/* Kernel sockets are not elevating the struct net refcount.
2248 		 * Instead, use a tracker to more easily detect if a layer
2249 		 * is not properly dismantling its kernel sockets at netns
2250 		 * destroy time.
2251 		 */
2252 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2253 				      false, priority);
2254 	}
2255 	sk_node_init(&newsk->sk_node);
2256 	sock_lock_init(newsk);
2257 	bh_lock_sock(newsk);
2258 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2259 	newsk->sk_backlog.len = 0;
2260 
2261 	atomic_set(&newsk->sk_rmem_alloc, 0);
2262 
2263 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2264 	refcount_set(&newsk->sk_wmem_alloc, 1);
2265 
2266 	atomic_set(&newsk->sk_omem_alloc, 0);
2267 	sk_init_common(newsk);
2268 
2269 	newsk->sk_dst_cache	= NULL;
2270 	newsk->sk_dst_pending_confirm = 0;
2271 	newsk->sk_wmem_queued	= 0;
2272 	newsk->sk_forward_alloc = 0;
2273 	newsk->sk_reserved_mem  = 0;
2274 	atomic_set(&newsk->sk_drops, 0);
2275 	newsk->sk_send_head	= NULL;
2276 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2277 	atomic_set(&newsk->sk_zckey, 0);
2278 
2279 	sock_reset_flag(newsk, SOCK_DONE);
2280 
2281 	/* sk->sk_memcg will be populated at accept() time */
2282 	newsk->sk_memcg = NULL;
2283 
2284 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2285 
2286 	rcu_read_lock();
2287 	filter = rcu_dereference(sk->sk_filter);
2288 	if (filter != NULL)
2289 		/* though it's an empty new sock, the charging may fail
2290 		 * if sysctl_optmem_max was changed between creation of
2291 		 * original socket and cloning
2292 		 */
2293 		is_charged = sk_filter_charge(newsk, filter);
2294 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2295 	rcu_read_unlock();
2296 
2297 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2298 		/* We need to make sure that we don't uncharge the new
2299 		 * socket if we couldn't charge it in the first place
2300 		 * as otherwise we uncharge the parent's filter.
2301 		 */
2302 		if (!is_charged)
2303 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2304 		sk_free_unlock_clone(newsk);
2305 		newsk = NULL;
2306 		goto out;
2307 	}
2308 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2309 
2310 	if (bpf_sk_storage_clone(sk, newsk)) {
2311 		sk_free_unlock_clone(newsk);
2312 		newsk = NULL;
2313 		goto out;
2314 	}
2315 
2316 	/* Clear sk_user_data if parent had the pointer tagged
2317 	 * as not suitable for copying when cloning.
2318 	 */
2319 	if (sk_user_data_is_nocopy(newsk))
2320 		newsk->sk_user_data = NULL;
2321 
2322 	newsk->sk_err	   = 0;
2323 	newsk->sk_err_soft = 0;
2324 	newsk->sk_priority = 0;
2325 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2326 
2327 	/* Before updating sk_refcnt, we must commit prior changes to memory
2328 	 * (Documentation/RCU/rculist_nulls.rst for details)
2329 	 */
2330 	smp_wmb();
2331 	refcount_set(&newsk->sk_refcnt, 2);
2332 
2333 	/* Increment the counter in the same struct proto as the master
2334 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2335 	 * is the same as sk->sk_prot->socks, as this field was copied
2336 	 * with memcpy).
2337 	 *
2338 	 * This _changes_ the previous behaviour, where
2339 	 * tcp_create_openreq_child always was incrementing the
2340 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2341 	 * to be taken into account in all callers. -acme
2342 	 */
2343 	sk_refcnt_debug_inc(newsk);
2344 	sk_set_socket(newsk, NULL);
2345 	sk_tx_queue_clear(newsk);
2346 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2347 
2348 	if (newsk->sk_prot->sockets_allocated)
2349 		sk_sockets_allocated_inc(newsk);
2350 
2351 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2352 		net_enable_timestamp();
2353 out:
2354 	return newsk;
2355 }
2356 EXPORT_SYMBOL_GPL(sk_clone_lock);
2357 
2358 void sk_free_unlock_clone(struct sock *sk)
2359 {
2360 	/* It is still raw copy of parent, so invalidate
2361 	 * destructor and make plain sk_free() */
2362 	sk->sk_destruct = NULL;
2363 	bh_unlock_sock(sk);
2364 	sk_free(sk);
2365 }
2366 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2367 
2368 static void sk_trim_gso_size(struct sock *sk)
2369 {
2370 	if (sk->sk_gso_max_size <= GSO_LEGACY_MAX_SIZE)
2371 		return;
2372 #if IS_ENABLED(CONFIG_IPV6)
2373 	if (sk->sk_family == AF_INET6 &&
2374 	    sk_is_tcp(sk) &&
2375 	    !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
2376 		return;
2377 #endif
2378 	sk->sk_gso_max_size = GSO_LEGACY_MAX_SIZE;
2379 }
2380 
2381 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2382 {
2383 	u32 max_segs = 1;
2384 
2385 	sk_dst_set(sk, dst);
2386 	sk->sk_route_caps = dst->dev->features;
2387 	if (sk_is_tcp(sk))
2388 		sk->sk_route_caps |= NETIF_F_GSO;
2389 	if (sk->sk_route_caps & NETIF_F_GSO)
2390 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2391 	if (unlikely(sk->sk_gso_disabled))
2392 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2393 	if (sk_can_gso(sk)) {
2394 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2395 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2396 		} else {
2397 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2398 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2399 			sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2400 			sk_trim_gso_size(sk);
2401 			sk->sk_gso_max_size -= (MAX_TCP_HEADER + 1);
2402 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2403 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2404 		}
2405 	}
2406 	sk->sk_gso_max_segs = max_segs;
2407 }
2408 EXPORT_SYMBOL_GPL(sk_setup_caps);
2409 
2410 /*
2411  *	Simple resource managers for sockets.
2412  */
2413 
2414 
2415 /*
2416  * Write buffer destructor automatically called from kfree_skb.
2417  */
2418 void sock_wfree(struct sk_buff *skb)
2419 {
2420 	struct sock *sk = skb->sk;
2421 	unsigned int len = skb->truesize;
2422 	bool free;
2423 
2424 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2425 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2426 		    sk->sk_write_space == sock_def_write_space) {
2427 			rcu_read_lock();
2428 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2429 			sock_def_write_space_wfree(sk);
2430 			rcu_read_unlock();
2431 			if (unlikely(free))
2432 				__sk_free(sk);
2433 			return;
2434 		}
2435 
2436 		/*
2437 		 * Keep a reference on sk_wmem_alloc, this will be released
2438 		 * after sk_write_space() call
2439 		 */
2440 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2441 		sk->sk_write_space(sk);
2442 		len = 1;
2443 	}
2444 	/*
2445 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2446 	 * could not do because of in-flight packets
2447 	 */
2448 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2449 		__sk_free(sk);
2450 }
2451 EXPORT_SYMBOL(sock_wfree);
2452 
2453 /* This variant of sock_wfree() is used by TCP,
2454  * since it sets SOCK_USE_WRITE_QUEUE.
2455  */
2456 void __sock_wfree(struct sk_buff *skb)
2457 {
2458 	struct sock *sk = skb->sk;
2459 
2460 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2461 		__sk_free(sk);
2462 }
2463 
2464 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2465 {
2466 	skb_orphan(skb);
2467 	skb->sk = sk;
2468 #ifdef CONFIG_INET
2469 	if (unlikely(!sk_fullsock(sk))) {
2470 		skb->destructor = sock_edemux;
2471 		sock_hold(sk);
2472 		return;
2473 	}
2474 #endif
2475 	skb->destructor = sock_wfree;
2476 	skb_set_hash_from_sk(skb, sk);
2477 	/*
2478 	 * We used to take a refcount on sk, but following operation
2479 	 * is enough to guarantee sk_free() wont free this sock until
2480 	 * all in-flight packets are completed
2481 	 */
2482 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2483 }
2484 EXPORT_SYMBOL(skb_set_owner_w);
2485 
2486 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2487 {
2488 #ifdef CONFIG_TLS_DEVICE
2489 	/* Drivers depend on in-order delivery for crypto offload,
2490 	 * partial orphan breaks out-of-order-OK logic.
2491 	 */
2492 	if (skb->decrypted)
2493 		return false;
2494 #endif
2495 	return (skb->destructor == sock_wfree ||
2496 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2497 }
2498 
2499 /* This helper is used by netem, as it can hold packets in its
2500  * delay queue. We want to allow the owner socket to send more
2501  * packets, as if they were already TX completed by a typical driver.
2502  * But we also want to keep skb->sk set because some packet schedulers
2503  * rely on it (sch_fq for example).
2504  */
2505 void skb_orphan_partial(struct sk_buff *skb)
2506 {
2507 	if (skb_is_tcp_pure_ack(skb))
2508 		return;
2509 
2510 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2511 		return;
2512 
2513 	skb_orphan(skb);
2514 }
2515 EXPORT_SYMBOL(skb_orphan_partial);
2516 
2517 /*
2518  * Read buffer destructor automatically called from kfree_skb.
2519  */
2520 void sock_rfree(struct sk_buff *skb)
2521 {
2522 	struct sock *sk = skb->sk;
2523 	unsigned int len = skb->truesize;
2524 
2525 	atomic_sub(len, &sk->sk_rmem_alloc);
2526 	sk_mem_uncharge(sk, len);
2527 }
2528 EXPORT_SYMBOL(sock_rfree);
2529 
2530 /*
2531  * Buffer destructor for skbs that are not used directly in read or write
2532  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2533  */
2534 void sock_efree(struct sk_buff *skb)
2535 {
2536 	sock_put(skb->sk);
2537 }
2538 EXPORT_SYMBOL(sock_efree);
2539 
2540 /* Buffer destructor for prefetch/receive path where reference count may
2541  * not be held, e.g. for listen sockets.
2542  */
2543 #ifdef CONFIG_INET
2544 void sock_pfree(struct sk_buff *skb)
2545 {
2546 	if (sk_is_refcounted(skb->sk))
2547 		sock_gen_put(skb->sk);
2548 }
2549 EXPORT_SYMBOL(sock_pfree);
2550 #endif /* CONFIG_INET */
2551 
2552 kuid_t sock_i_uid(struct sock *sk)
2553 {
2554 	kuid_t uid;
2555 
2556 	read_lock_bh(&sk->sk_callback_lock);
2557 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2558 	read_unlock_bh(&sk->sk_callback_lock);
2559 	return uid;
2560 }
2561 EXPORT_SYMBOL(sock_i_uid);
2562 
2563 unsigned long sock_i_ino(struct sock *sk)
2564 {
2565 	unsigned long ino;
2566 
2567 	read_lock_bh(&sk->sk_callback_lock);
2568 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2569 	read_unlock_bh(&sk->sk_callback_lock);
2570 	return ino;
2571 }
2572 EXPORT_SYMBOL(sock_i_ino);
2573 
2574 /*
2575  * Allocate a skb from the socket's send buffer.
2576  */
2577 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2578 			     gfp_t priority)
2579 {
2580 	if (force ||
2581 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2582 		struct sk_buff *skb = alloc_skb(size, priority);
2583 
2584 		if (skb) {
2585 			skb_set_owner_w(skb, sk);
2586 			return skb;
2587 		}
2588 	}
2589 	return NULL;
2590 }
2591 EXPORT_SYMBOL(sock_wmalloc);
2592 
2593 static void sock_ofree(struct sk_buff *skb)
2594 {
2595 	struct sock *sk = skb->sk;
2596 
2597 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2598 }
2599 
2600 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2601 			     gfp_t priority)
2602 {
2603 	struct sk_buff *skb;
2604 
2605 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2606 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2607 	    READ_ONCE(sysctl_optmem_max))
2608 		return NULL;
2609 
2610 	skb = alloc_skb(size, priority);
2611 	if (!skb)
2612 		return NULL;
2613 
2614 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2615 	skb->sk = sk;
2616 	skb->destructor = sock_ofree;
2617 	return skb;
2618 }
2619 
2620 /*
2621  * Allocate a memory block from the socket's option memory buffer.
2622  */
2623 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2624 {
2625 	int optmem_max = READ_ONCE(sysctl_optmem_max);
2626 
2627 	if ((unsigned int)size <= optmem_max &&
2628 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2629 		void *mem;
2630 		/* First do the add, to avoid the race if kmalloc
2631 		 * might sleep.
2632 		 */
2633 		atomic_add(size, &sk->sk_omem_alloc);
2634 		mem = kmalloc(size, priority);
2635 		if (mem)
2636 			return mem;
2637 		atomic_sub(size, &sk->sk_omem_alloc);
2638 	}
2639 	return NULL;
2640 }
2641 EXPORT_SYMBOL(sock_kmalloc);
2642 
2643 /* Free an option memory block. Note, we actually want the inline
2644  * here as this allows gcc to detect the nullify and fold away the
2645  * condition entirely.
2646  */
2647 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2648 				  const bool nullify)
2649 {
2650 	if (WARN_ON_ONCE(!mem))
2651 		return;
2652 	if (nullify)
2653 		kfree_sensitive(mem);
2654 	else
2655 		kfree(mem);
2656 	atomic_sub(size, &sk->sk_omem_alloc);
2657 }
2658 
2659 void sock_kfree_s(struct sock *sk, void *mem, int size)
2660 {
2661 	__sock_kfree_s(sk, mem, size, false);
2662 }
2663 EXPORT_SYMBOL(sock_kfree_s);
2664 
2665 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2666 {
2667 	__sock_kfree_s(sk, mem, size, true);
2668 }
2669 EXPORT_SYMBOL(sock_kzfree_s);
2670 
2671 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2672    I think, these locks should be removed for datagram sockets.
2673  */
2674 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2675 {
2676 	DEFINE_WAIT(wait);
2677 
2678 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2679 	for (;;) {
2680 		if (!timeo)
2681 			break;
2682 		if (signal_pending(current))
2683 			break;
2684 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2685 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2686 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2687 			break;
2688 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2689 			break;
2690 		if (sk->sk_err)
2691 			break;
2692 		timeo = schedule_timeout(timeo);
2693 	}
2694 	finish_wait(sk_sleep(sk), &wait);
2695 	return timeo;
2696 }
2697 
2698 
2699 /*
2700  *	Generic send/receive buffer handlers
2701  */
2702 
2703 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2704 				     unsigned long data_len, int noblock,
2705 				     int *errcode, int max_page_order)
2706 {
2707 	struct sk_buff *skb;
2708 	long timeo;
2709 	int err;
2710 
2711 	timeo = sock_sndtimeo(sk, noblock);
2712 	for (;;) {
2713 		err = sock_error(sk);
2714 		if (err != 0)
2715 			goto failure;
2716 
2717 		err = -EPIPE;
2718 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2719 			goto failure;
2720 
2721 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2722 			break;
2723 
2724 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2725 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2726 		err = -EAGAIN;
2727 		if (!timeo)
2728 			goto failure;
2729 		if (signal_pending(current))
2730 			goto interrupted;
2731 		timeo = sock_wait_for_wmem(sk, timeo);
2732 	}
2733 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2734 				   errcode, sk->sk_allocation);
2735 	if (skb)
2736 		skb_set_owner_w(skb, sk);
2737 	return skb;
2738 
2739 interrupted:
2740 	err = sock_intr_errno(timeo);
2741 failure:
2742 	*errcode = err;
2743 	return NULL;
2744 }
2745 EXPORT_SYMBOL(sock_alloc_send_pskb);
2746 
2747 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2748 		     struct sockcm_cookie *sockc)
2749 {
2750 	u32 tsflags;
2751 
2752 	switch (cmsg->cmsg_type) {
2753 	case SO_MARK:
2754 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2755 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2756 			return -EPERM;
2757 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2758 			return -EINVAL;
2759 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2760 		break;
2761 	case SO_TIMESTAMPING_OLD:
2762 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2763 			return -EINVAL;
2764 
2765 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2766 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2767 			return -EINVAL;
2768 
2769 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2770 		sockc->tsflags |= tsflags;
2771 		break;
2772 	case SCM_TXTIME:
2773 		if (!sock_flag(sk, SOCK_TXTIME))
2774 			return -EINVAL;
2775 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2776 			return -EINVAL;
2777 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2778 		break;
2779 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2780 	case SCM_RIGHTS:
2781 	case SCM_CREDENTIALS:
2782 		break;
2783 	default:
2784 		return -EINVAL;
2785 	}
2786 	return 0;
2787 }
2788 EXPORT_SYMBOL(__sock_cmsg_send);
2789 
2790 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2791 		   struct sockcm_cookie *sockc)
2792 {
2793 	struct cmsghdr *cmsg;
2794 	int ret;
2795 
2796 	for_each_cmsghdr(cmsg, msg) {
2797 		if (!CMSG_OK(msg, cmsg))
2798 			return -EINVAL;
2799 		if (cmsg->cmsg_level != SOL_SOCKET)
2800 			continue;
2801 		ret = __sock_cmsg_send(sk, cmsg, sockc);
2802 		if (ret)
2803 			return ret;
2804 	}
2805 	return 0;
2806 }
2807 EXPORT_SYMBOL(sock_cmsg_send);
2808 
2809 static void sk_enter_memory_pressure(struct sock *sk)
2810 {
2811 	if (!sk->sk_prot->enter_memory_pressure)
2812 		return;
2813 
2814 	sk->sk_prot->enter_memory_pressure(sk);
2815 }
2816 
2817 static void sk_leave_memory_pressure(struct sock *sk)
2818 {
2819 	if (sk->sk_prot->leave_memory_pressure) {
2820 		sk->sk_prot->leave_memory_pressure(sk);
2821 	} else {
2822 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2823 
2824 		if (memory_pressure && READ_ONCE(*memory_pressure))
2825 			WRITE_ONCE(*memory_pressure, 0);
2826 	}
2827 }
2828 
2829 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2830 
2831 /**
2832  * skb_page_frag_refill - check that a page_frag contains enough room
2833  * @sz: minimum size of the fragment we want to get
2834  * @pfrag: pointer to page_frag
2835  * @gfp: priority for memory allocation
2836  *
2837  * Note: While this allocator tries to use high order pages, there is
2838  * no guarantee that allocations succeed. Therefore, @sz MUST be
2839  * less or equal than PAGE_SIZE.
2840  */
2841 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2842 {
2843 	if (pfrag->page) {
2844 		if (page_ref_count(pfrag->page) == 1) {
2845 			pfrag->offset = 0;
2846 			return true;
2847 		}
2848 		if (pfrag->offset + sz <= pfrag->size)
2849 			return true;
2850 		put_page(pfrag->page);
2851 	}
2852 
2853 	pfrag->offset = 0;
2854 	if (SKB_FRAG_PAGE_ORDER &&
2855 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2856 		/* Avoid direct reclaim but allow kswapd to wake */
2857 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2858 					  __GFP_COMP | __GFP_NOWARN |
2859 					  __GFP_NORETRY,
2860 					  SKB_FRAG_PAGE_ORDER);
2861 		if (likely(pfrag->page)) {
2862 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2863 			return true;
2864 		}
2865 	}
2866 	pfrag->page = alloc_page(gfp);
2867 	if (likely(pfrag->page)) {
2868 		pfrag->size = PAGE_SIZE;
2869 		return true;
2870 	}
2871 	return false;
2872 }
2873 EXPORT_SYMBOL(skb_page_frag_refill);
2874 
2875 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2876 {
2877 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2878 		return true;
2879 
2880 	sk_enter_memory_pressure(sk);
2881 	sk_stream_moderate_sndbuf(sk);
2882 	return false;
2883 }
2884 EXPORT_SYMBOL(sk_page_frag_refill);
2885 
2886 void __lock_sock(struct sock *sk)
2887 	__releases(&sk->sk_lock.slock)
2888 	__acquires(&sk->sk_lock.slock)
2889 {
2890 	DEFINE_WAIT(wait);
2891 
2892 	for (;;) {
2893 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2894 					TASK_UNINTERRUPTIBLE);
2895 		spin_unlock_bh(&sk->sk_lock.slock);
2896 		schedule();
2897 		spin_lock_bh(&sk->sk_lock.slock);
2898 		if (!sock_owned_by_user(sk))
2899 			break;
2900 	}
2901 	finish_wait(&sk->sk_lock.wq, &wait);
2902 }
2903 
2904 void __release_sock(struct sock *sk)
2905 	__releases(&sk->sk_lock.slock)
2906 	__acquires(&sk->sk_lock.slock)
2907 {
2908 	struct sk_buff *skb, *next;
2909 
2910 	while ((skb = sk->sk_backlog.head) != NULL) {
2911 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2912 
2913 		spin_unlock_bh(&sk->sk_lock.slock);
2914 
2915 		do {
2916 			next = skb->next;
2917 			prefetch(next);
2918 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2919 			skb_mark_not_on_list(skb);
2920 			sk_backlog_rcv(sk, skb);
2921 
2922 			cond_resched();
2923 
2924 			skb = next;
2925 		} while (skb != NULL);
2926 
2927 		spin_lock_bh(&sk->sk_lock.slock);
2928 	}
2929 
2930 	/*
2931 	 * Doing the zeroing here guarantee we can not loop forever
2932 	 * while a wild producer attempts to flood us.
2933 	 */
2934 	sk->sk_backlog.len = 0;
2935 }
2936 
2937 void __sk_flush_backlog(struct sock *sk)
2938 {
2939 	spin_lock_bh(&sk->sk_lock.slock);
2940 	__release_sock(sk);
2941 	spin_unlock_bh(&sk->sk_lock.slock);
2942 }
2943 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2944 
2945 /**
2946  * sk_wait_data - wait for data to arrive at sk_receive_queue
2947  * @sk:    sock to wait on
2948  * @timeo: for how long
2949  * @skb:   last skb seen on sk_receive_queue
2950  *
2951  * Now socket state including sk->sk_err is changed only under lock,
2952  * hence we may omit checks after joining wait queue.
2953  * We check receive queue before schedule() only as optimization;
2954  * it is very likely that release_sock() added new data.
2955  */
2956 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2957 {
2958 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2959 	int rc;
2960 
2961 	add_wait_queue(sk_sleep(sk), &wait);
2962 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2963 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2964 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2965 	remove_wait_queue(sk_sleep(sk), &wait);
2966 	return rc;
2967 }
2968 EXPORT_SYMBOL(sk_wait_data);
2969 
2970 /**
2971  *	__sk_mem_raise_allocated - increase memory_allocated
2972  *	@sk: socket
2973  *	@size: memory size to allocate
2974  *	@amt: pages to allocate
2975  *	@kind: allocation type
2976  *
2977  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2978  */
2979 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2980 {
2981 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2982 	struct proto *prot = sk->sk_prot;
2983 	bool charged = true;
2984 	long allocated;
2985 
2986 	sk_memory_allocated_add(sk, amt);
2987 	allocated = sk_memory_allocated(sk);
2988 	if (memcg_charge &&
2989 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2990 						gfp_memcg_charge())))
2991 		goto suppress_allocation;
2992 
2993 	/* Under limit. */
2994 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2995 		sk_leave_memory_pressure(sk);
2996 		return 1;
2997 	}
2998 
2999 	/* Under pressure. */
3000 	if (allocated > sk_prot_mem_limits(sk, 1))
3001 		sk_enter_memory_pressure(sk);
3002 
3003 	/* Over hard limit. */
3004 	if (allocated > sk_prot_mem_limits(sk, 2))
3005 		goto suppress_allocation;
3006 
3007 	/* guarantee minimum buffer size under pressure */
3008 	if (kind == SK_MEM_RECV) {
3009 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3010 			return 1;
3011 
3012 	} else { /* SK_MEM_SEND */
3013 		int wmem0 = sk_get_wmem0(sk, prot);
3014 
3015 		if (sk->sk_type == SOCK_STREAM) {
3016 			if (sk->sk_wmem_queued < wmem0)
3017 				return 1;
3018 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3019 				return 1;
3020 		}
3021 	}
3022 
3023 	if (sk_has_memory_pressure(sk)) {
3024 		u64 alloc;
3025 
3026 		if (!sk_under_memory_pressure(sk))
3027 			return 1;
3028 		alloc = sk_sockets_allocated_read_positive(sk);
3029 		if (sk_prot_mem_limits(sk, 2) > alloc *
3030 		    sk_mem_pages(sk->sk_wmem_queued +
3031 				 atomic_read(&sk->sk_rmem_alloc) +
3032 				 sk->sk_forward_alloc))
3033 			return 1;
3034 	}
3035 
3036 suppress_allocation:
3037 
3038 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3039 		sk_stream_moderate_sndbuf(sk);
3040 
3041 		/* Fail only if socket is _under_ its sndbuf.
3042 		 * In this case we cannot block, so that we have to fail.
3043 		 */
3044 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3045 			/* Force charge with __GFP_NOFAIL */
3046 			if (memcg_charge && !charged) {
3047 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3048 					gfp_memcg_charge() | __GFP_NOFAIL);
3049 			}
3050 			return 1;
3051 		}
3052 	}
3053 
3054 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3055 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3056 
3057 	sk_memory_allocated_sub(sk, amt);
3058 
3059 	if (memcg_charge && charged)
3060 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3061 
3062 	return 0;
3063 }
3064 
3065 /**
3066  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3067  *	@sk: socket
3068  *	@size: memory size to allocate
3069  *	@kind: allocation type
3070  *
3071  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3072  *	rmem allocation. This function assumes that protocols which have
3073  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3074  */
3075 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3076 {
3077 	int ret, amt = sk_mem_pages(size);
3078 
3079 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3080 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3081 	if (!ret)
3082 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3083 	return ret;
3084 }
3085 EXPORT_SYMBOL(__sk_mem_schedule);
3086 
3087 /**
3088  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3089  *	@sk: socket
3090  *	@amount: number of quanta
3091  *
3092  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3093  */
3094 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3095 {
3096 	sk_memory_allocated_sub(sk, amount);
3097 
3098 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3099 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3100 
3101 	if (sk_under_memory_pressure(sk) &&
3102 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3103 		sk_leave_memory_pressure(sk);
3104 }
3105 
3106 /**
3107  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3108  *	@sk: socket
3109  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3110  */
3111 void __sk_mem_reclaim(struct sock *sk, int amount)
3112 {
3113 	amount >>= PAGE_SHIFT;
3114 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3115 	__sk_mem_reduce_allocated(sk, amount);
3116 }
3117 EXPORT_SYMBOL(__sk_mem_reclaim);
3118 
3119 int sk_set_peek_off(struct sock *sk, int val)
3120 {
3121 	sk->sk_peek_off = val;
3122 	return 0;
3123 }
3124 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3125 
3126 /*
3127  * Set of default routines for initialising struct proto_ops when
3128  * the protocol does not support a particular function. In certain
3129  * cases where it makes no sense for a protocol to have a "do nothing"
3130  * function, some default processing is provided.
3131  */
3132 
3133 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3134 {
3135 	return -EOPNOTSUPP;
3136 }
3137 EXPORT_SYMBOL(sock_no_bind);
3138 
3139 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3140 		    int len, int flags)
3141 {
3142 	return -EOPNOTSUPP;
3143 }
3144 EXPORT_SYMBOL(sock_no_connect);
3145 
3146 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3147 {
3148 	return -EOPNOTSUPP;
3149 }
3150 EXPORT_SYMBOL(sock_no_socketpair);
3151 
3152 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3153 		   bool kern)
3154 {
3155 	return -EOPNOTSUPP;
3156 }
3157 EXPORT_SYMBOL(sock_no_accept);
3158 
3159 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3160 		    int peer)
3161 {
3162 	return -EOPNOTSUPP;
3163 }
3164 EXPORT_SYMBOL(sock_no_getname);
3165 
3166 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3167 {
3168 	return -EOPNOTSUPP;
3169 }
3170 EXPORT_SYMBOL(sock_no_ioctl);
3171 
3172 int sock_no_listen(struct socket *sock, int backlog)
3173 {
3174 	return -EOPNOTSUPP;
3175 }
3176 EXPORT_SYMBOL(sock_no_listen);
3177 
3178 int sock_no_shutdown(struct socket *sock, int how)
3179 {
3180 	return -EOPNOTSUPP;
3181 }
3182 EXPORT_SYMBOL(sock_no_shutdown);
3183 
3184 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3185 {
3186 	return -EOPNOTSUPP;
3187 }
3188 EXPORT_SYMBOL(sock_no_sendmsg);
3189 
3190 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3191 {
3192 	return -EOPNOTSUPP;
3193 }
3194 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3195 
3196 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3197 		    int flags)
3198 {
3199 	return -EOPNOTSUPP;
3200 }
3201 EXPORT_SYMBOL(sock_no_recvmsg);
3202 
3203 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3204 {
3205 	/* Mirror missing mmap method error code */
3206 	return -ENODEV;
3207 }
3208 EXPORT_SYMBOL(sock_no_mmap);
3209 
3210 /*
3211  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3212  * various sock-based usage counts.
3213  */
3214 void __receive_sock(struct file *file)
3215 {
3216 	struct socket *sock;
3217 
3218 	sock = sock_from_file(file);
3219 	if (sock) {
3220 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3221 		sock_update_classid(&sock->sk->sk_cgrp_data);
3222 	}
3223 }
3224 
3225 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3226 {
3227 	ssize_t res;
3228 	struct msghdr msg = {.msg_flags = flags};
3229 	struct kvec iov;
3230 	char *kaddr = kmap(page);
3231 	iov.iov_base = kaddr + offset;
3232 	iov.iov_len = size;
3233 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3234 	kunmap(page);
3235 	return res;
3236 }
3237 EXPORT_SYMBOL(sock_no_sendpage);
3238 
3239 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3240 				int offset, size_t size, int flags)
3241 {
3242 	ssize_t res;
3243 	struct msghdr msg = {.msg_flags = flags};
3244 	struct kvec iov;
3245 	char *kaddr = kmap(page);
3246 
3247 	iov.iov_base = kaddr + offset;
3248 	iov.iov_len = size;
3249 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3250 	kunmap(page);
3251 	return res;
3252 }
3253 EXPORT_SYMBOL(sock_no_sendpage_locked);
3254 
3255 /*
3256  *	Default Socket Callbacks
3257  */
3258 
3259 static void sock_def_wakeup(struct sock *sk)
3260 {
3261 	struct socket_wq *wq;
3262 
3263 	rcu_read_lock();
3264 	wq = rcu_dereference(sk->sk_wq);
3265 	if (skwq_has_sleeper(wq))
3266 		wake_up_interruptible_all(&wq->wait);
3267 	rcu_read_unlock();
3268 }
3269 
3270 static void sock_def_error_report(struct sock *sk)
3271 {
3272 	struct socket_wq *wq;
3273 
3274 	rcu_read_lock();
3275 	wq = rcu_dereference(sk->sk_wq);
3276 	if (skwq_has_sleeper(wq))
3277 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3278 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3279 	rcu_read_unlock();
3280 }
3281 
3282 void sock_def_readable(struct sock *sk)
3283 {
3284 	struct socket_wq *wq;
3285 
3286 	rcu_read_lock();
3287 	wq = rcu_dereference(sk->sk_wq);
3288 	if (skwq_has_sleeper(wq))
3289 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3290 						EPOLLRDNORM | EPOLLRDBAND);
3291 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3292 	rcu_read_unlock();
3293 }
3294 
3295 static void sock_def_write_space(struct sock *sk)
3296 {
3297 	struct socket_wq *wq;
3298 
3299 	rcu_read_lock();
3300 
3301 	/* Do not wake up a writer until he can make "significant"
3302 	 * progress.  --DaveM
3303 	 */
3304 	if (sock_writeable(sk)) {
3305 		wq = rcu_dereference(sk->sk_wq);
3306 		if (skwq_has_sleeper(wq))
3307 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3308 						EPOLLWRNORM | EPOLLWRBAND);
3309 
3310 		/* Should agree with poll, otherwise some programs break */
3311 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3312 	}
3313 
3314 	rcu_read_unlock();
3315 }
3316 
3317 /* An optimised version of sock_def_write_space(), should only be called
3318  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3319  * ->sk_wmem_alloc.
3320  */
3321 static void sock_def_write_space_wfree(struct sock *sk)
3322 {
3323 	/* Do not wake up a writer until he can make "significant"
3324 	 * progress.  --DaveM
3325 	 */
3326 	if (sock_writeable(sk)) {
3327 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3328 
3329 		/* rely on refcount_sub from sock_wfree() */
3330 		smp_mb__after_atomic();
3331 		if (wq && waitqueue_active(&wq->wait))
3332 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3333 						EPOLLWRNORM | EPOLLWRBAND);
3334 
3335 		/* Should agree with poll, otherwise some programs break */
3336 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3337 	}
3338 }
3339 
3340 static void sock_def_destruct(struct sock *sk)
3341 {
3342 }
3343 
3344 void sk_send_sigurg(struct sock *sk)
3345 {
3346 	if (sk->sk_socket && sk->sk_socket->file)
3347 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3348 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3349 }
3350 EXPORT_SYMBOL(sk_send_sigurg);
3351 
3352 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3353 		    unsigned long expires)
3354 {
3355 	if (!mod_timer(timer, expires))
3356 		sock_hold(sk);
3357 }
3358 EXPORT_SYMBOL(sk_reset_timer);
3359 
3360 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3361 {
3362 	if (del_timer(timer))
3363 		__sock_put(sk);
3364 }
3365 EXPORT_SYMBOL(sk_stop_timer);
3366 
3367 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3368 {
3369 	if (del_timer_sync(timer))
3370 		__sock_put(sk);
3371 }
3372 EXPORT_SYMBOL(sk_stop_timer_sync);
3373 
3374 void sock_init_data(struct socket *sock, struct sock *sk)
3375 {
3376 	sk_init_common(sk);
3377 	sk->sk_send_head	=	NULL;
3378 
3379 	timer_setup(&sk->sk_timer, NULL, 0);
3380 
3381 	sk->sk_allocation	=	GFP_KERNEL;
3382 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3383 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3384 	sk->sk_state		=	TCP_CLOSE;
3385 	sk_set_socket(sk, sock);
3386 
3387 	sock_set_flag(sk, SOCK_ZAPPED);
3388 
3389 	if (sock) {
3390 		sk->sk_type	=	sock->type;
3391 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3392 		sock->sk	=	sk;
3393 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3394 	} else {
3395 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3396 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3397 	}
3398 
3399 	rwlock_init(&sk->sk_callback_lock);
3400 	if (sk->sk_kern_sock)
3401 		lockdep_set_class_and_name(
3402 			&sk->sk_callback_lock,
3403 			af_kern_callback_keys + sk->sk_family,
3404 			af_family_kern_clock_key_strings[sk->sk_family]);
3405 	else
3406 		lockdep_set_class_and_name(
3407 			&sk->sk_callback_lock,
3408 			af_callback_keys + sk->sk_family,
3409 			af_family_clock_key_strings[sk->sk_family]);
3410 
3411 	sk->sk_state_change	=	sock_def_wakeup;
3412 	sk->sk_data_ready	=	sock_def_readable;
3413 	sk->sk_write_space	=	sock_def_write_space;
3414 	sk->sk_error_report	=	sock_def_error_report;
3415 	sk->sk_destruct		=	sock_def_destruct;
3416 
3417 	sk->sk_frag.page	=	NULL;
3418 	sk->sk_frag.offset	=	0;
3419 	sk->sk_peek_off		=	-1;
3420 
3421 	sk->sk_peer_pid 	=	NULL;
3422 	sk->sk_peer_cred	=	NULL;
3423 	spin_lock_init(&sk->sk_peer_lock);
3424 
3425 	sk->sk_write_pending	=	0;
3426 	sk->sk_rcvlowat		=	1;
3427 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3428 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3429 
3430 	sk->sk_stamp = SK_DEFAULT_STAMP;
3431 #if BITS_PER_LONG==32
3432 	seqlock_init(&sk->sk_stamp_seq);
3433 #endif
3434 	atomic_set(&sk->sk_zckey, 0);
3435 
3436 #ifdef CONFIG_NET_RX_BUSY_POLL
3437 	sk->sk_napi_id		=	0;
3438 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3439 #endif
3440 
3441 	sk->sk_max_pacing_rate = ~0UL;
3442 	sk->sk_pacing_rate = ~0UL;
3443 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3444 	sk->sk_incoming_cpu = -1;
3445 	sk->sk_txrehash = SOCK_TXREHASH_DEFAULT;
3446 
3447 	sk_rx_queue_clear(sk);
3448 	/*
3449 	 * Before updating sk_refcnt, we must commit prior changes to memory
3450 	 * (Documentation/RCU/rculist_nulls.rst for details)
3451 	 */
3452 	smp_wmb();
3453 	refcount_set(&sk->sk_refcnt, 1);
3454 	atomic_set(&sk->sk_drops, 0);
3455 }
3456 EXPORT_SYMBOL(sock_init_data);
3457 
3458 void lock_sock_nested(struct sock *sk, int subclass)
3459 {
3460 	/* The sk_lock has mutex_lock() semantics here. */
3461 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3462 
3463 	might_sleep();
3464 	spin_lock_bh(&sk->sk_lock.slock);
3465 	if (sock_owned_by_user_nocheck(sk))
3466 		__lock_sock(sk);
3467 	sk->sk_lock.owned = 1;
3468 	spin_unlock_bh(&sk->sk_lock.slock);
3469 }
3470 EXPORT_SYMBOL(lock_sock_nested);
3471 
3472 void release_sock(struct sock *sk)
3473 {
3474 	spin_lock_bh(&sk->sk_lock.slock);
3475 	if (sk->sk_backlog.tail)
3476 		__release_sock(sk);
3477 
3478 	/* Warning : release_cb() might need to release sk ownership,
3479 	 * ie call sock_release_ownership(sk) before us.
3480 	 */
3481 	if (sk->sk_prot->release_cb)
3482 		sk->sk_prot->release_cb(sk);
3483 
3484 	sock_release_ownership(sk);
3485 	if (waitqueue_active(&sk->sk_lock.wq))
3486 		wake_up(&sk->sk_lock.wq);
3487 	spin_unlock_bh(&sk->sk_lock.slock);
3488 }
3489 EXPORT_SYMBOL(release_sock);
3490 
3491 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3492 {
3493 	might_sleep();
3494 	spin_lock_bh(&sk->sk_lock.slock);
3495 
3496 	if (!sock_owned_by_user_nocheck(sk)) {
3497 		/*
3498 		 * Fast path return with bottom halves disabled and
3499 		 * sock::sk_lock.slock held.
3500 		 *
3501 		 * The 'mutex' is not contended and holding
3502 		 * sock::sk_lock.slock prevents all other lockers to
3503 		 * proceed so the corresponding unlock_sock_fast() can
3504 		 * avoid the slow path of release_sock() completely and
3505 		 * just release slock.
3506 		 *
3507 		 * From a semantical POV this is equivalent to 'acquiring'
3508 		 * the 'mutex', hence the corresponding lockdep
3509 		 * mutex_release() has to happen in the fast path of
3510 		 * unlock_sock_fast().
3511 		 */
3512 		return false;
3513 	}
3514 
3515 	__lock_sock(sk);
3516 	sk->sk_lock.owned = 1;
3517 	__acquire(&sk->sk_lock.slock);
3518 	spin_unlock_bh(&sk->sk_lock.slock);
3519 	return true;
3520 }
3521 EXPORT_SYMBOL(__lock_sock_fast);
3522 
3523 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3524 		   bool timeval, bool time32)
3525 {
3526 	struct sock *sk = sock->sk;
3527 	struct timespec64 ts;
3528 
3529 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3530 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3531 	if (ts.tv_sec == -1)
3532 		return -ENOENT;
3533 	if (ts.tv_sec == 0) {
3534 		ktime_t kt = ktime_get_real();
3535 		sock_write_timestamp(sk, kt);
3536 		ts = ktime_to_timespec64(kt);
3537 	}
3538 
3539 	if (timeval)
3540 		ts.tv_nsec /= 1000;
3541 
3542 #ifdef CONFIG_COMPAT_32BIT_TIME
3543 	if (time32)
3544 		return put_old_timespec32(&ts, userstamp);
3545 #endif
3546 #ifdef CONFIG_SPARC64
3547 	/* beware of padding in sparc64 timeval */
3548 	if (timeval && !in_compat_syscall()) {
3549 		struct __kernel_old_timeval __user tv = {
3550 			.tv_sec = ts.tv_sec,
3551 			.tv_usec = ts.tv_nsec,
3552 		};
3553 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3554 			return -EFAULT;
3555 		return 0;
3556 	}
3557 #endif
3558 	return put_timespec64(&ts, userstamp);
3559 }
3560 EXPORT_SYMBOL(sock_gettstamp);
3561 
3562 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3563 {
3564 	if (!sock_flag(sk, flag)) {
3565 		unsigned long previous_flags = sk->sk_flags;
3566 
3567 		sock_set_flag(sk, flag);
3568 		/*
3569 		 * we just set one of the two flags which require net
3570 		 * time stamping, but time stamping might have been on
3571 		 * already because of the other one
3572 		 */
3573 		if (sock_needs_netstamp(sk) &&
3574 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3575 			net_enable_timestamp();
3576 	}
3577 }
3578 
3579 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3580 		       int level, int type)
3581 {
3582 	struct sock_exterr_skb *serr;
3583 	struct sk_buff *skb;
3584 	int copied, err;
3585 
3586 	err = -EAGAIN;
3587 	skb = sock_dequeue_err_skb(sk);
3588 	if (skb == NULL)
3589 		goto out;
3590 
3591 	copied = skb->len;
3592 	if (copied > len) {
3593 		msg->msg_flags |= MSG_TRUNC;
3594 		copied = len;
3595 	}
3596 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3597 	if (err)
3598 		goto out_free_skb;
3599 
3600 	sock_recv_timestamp(msg, sk, skb);
3601 
3602 	serr = SKB_EXT_ERR(skb);
3603 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3604 
3605 	msg->msg_flags |= MSG_ERRQUEUE;
3606 	err = copied;
3607 
3608 out_free_skb:
3609 	kfree_skb(skb);
3610 out:
3611 	return err;
3612 }
3613 EXPORT_SYMBOL(sock_recv_errqueue);
3614 
3615 /*
3616  *	Get a socket option on an socket.
3617  *
3618  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3619  *	asynchronous errors should be reported by getsockopt. We assume
3620  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3621  */
3622 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3623 			   char __user *optval, int __user *optlen)
3624 {
3625 	struct sock *sk = sock->sk;
3626 
3627 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3628 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3629 }
3630 EXPORT_SYMBOL(sock_common_getsockopt);
3631 
3632 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3633 			int flags)
3634 {
3635 	struct sock *sk = sock->sk;
3636 	int addr_len = 0;
3637 	int err;
3638 
3639 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3640 	if (err >= 0)
3641 		msg->msg_namelen = addr_len;
3642 	return err;
3643 }
3644 EXPORT_SYMBOL(sock_common_recvmsg);
3645 
3646 /*
3647  *	Set socket options on an inet socket.
3648  */
3649 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3650 			   sockptr_t optval, unsigned int optlen)
3651 {
3652 	struct sock *sk = sock->sk;
3653 
3654 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3655 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3656 }
3657 EXPORT_SYMBOL(sock_common_setsockopt);
3658 
3659 void sk_common_release(struct sock *sk)
3660 {
3661 	if (sk->sk_prot->destroy)
3662 		sk->sk_prot->destroy(sk);
3663 
3664 	/*
3665 	 * Observation: when sk_common_release is called, processes have
3666 	 * no access to socket. But net still has.
3667 	 * Step one, detach it from networking:
3668 	 *
3669 	 * A. Remove from hash tables.
3670 	 */
3671 
3672 	sk->sk_prot->unhash(sk);
3673 
3674 	/*
3675 	 * In this point socket cannot receive new packets, but it is possible
3676 	 * that some packets are in flight because some CPU runs receiver and
3677 	 * did hash table lookup before we unhashed socket. They will achieve
3678 	 * receive queue and will be purged by socket destructor.
3679 	 *
3680 	 * Also we still have packets pending on receive queue and probably,
3681 	 * our own packets waiting in device queues. sock_destroy will drain
3682 	 * receive queue, but transmitted packets will delay socket destruction
3683 	 * until the last reference will be released.
3684 	 */
3685 
3686 	sock_orphan(sk);
3687 
3688 	xfrm_sk_free_policy(sk);
3689 
3690 	sk_refcnt_debug_release(sk);
3691 
3692 	sock_put(sk);
3693 }
3694 EXPORT_SYMBOL(sk_common_release);
3695 
3696 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3697 {
3698 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3699 
3700 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3701 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3702 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3703 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3704 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3705 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3706 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3707 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3708 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3709 }
3710 
3711 #ifdef CONFIG_PROC_FS
3712 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3713 
3714 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3715 {
3716 	int cpu, idx = prot->inuse_idx;
3717 	int res = 0;
3718 
3719 	for_each_possible_cpu(cpu)
3720 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3721 
3722 	return res >= 0 ? res : 0;
3723 }
3724 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3725 
3726 int sock_inuse_get(struct net *net)
3727 {
3728 	int cpu, res = 0;
3729 
3730 	for_each_possible_cpu(cpu)
3731 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3732 
3733 	return res;
3734 }
3735 
3736 EXPORT_SYMBOL_GPL(sock_inuse_get);
3737 
3738 static int __net_init sock_inuse_init_net(struct net *net)
3739 {
3740 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3741 	if (net->core.prot_inuse == NULL)
3742 		return -ENOMEM;
3743 	return 0;
3744 }
3745 
3746 static void __net_exit sock_inuse_exit_net(struct net *net)
3747 {
3748 	free_percpu(net->core.prot_inuse);
3749 }
3750 
3751 static struct pernet_operations net_inuse_ops = {
3752 	.init = sock_inuse_init_net,
3753 	.exit = sock_inuse_exit_net,
3754 };
3755 
3756 static __init int net_inuse_init(void)
3757 {
3758 	if (register_pernet_subsys(&net_inuse_ops))
3759 		panic("Cannot initialize net inuse counters");
3760 
3761 	return 0;
3762 }
3763 
3764 core_initcall(net_inuse_init);
3765 
3766 static int assign_proto_idx(struct proto *prot)
3767 {
3768 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3769 
3770 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3771 		pr_err("PROTO_INUSE_NR exhausted\n");
3772 		return -ENOSPC;
3773 	}
3774 
3775 	set_bit(prot->inuse_idx, proto_inuse_idx);
3776 	return 0;
3777 }
3778 
3779 static void release_proto_idx(struct proto *prot)
3780 {
3781 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3782 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3783 }
3784 #else
3785 static inline int assign_proto_idx(struct proto *prot)
3786 {
3787 	return 0;
3788 }
3789 
3790 static inline void release_proto_idx(struct proto *prot)
3791 {
3792 }
3793 
3794 #endif
3795 
3796 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3797 {
3798 	if (!twsk_prot)
3799 		return;
3800 	kfree(twsk_prot->twsk_slab_name);
3801 	twsk_prot->twsk_slab_name = NULL;
3802 	kmem_cache_destroy(twsk_prot->twsk_slab);
3803 	twsk_prot->twsk_slab = NULL;
3804 }
3805 
3806 static int tw_prot_init(const struct proto *prot)
3807 {
3808 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3809 
3810 	if (!twsk_prot)
3811 		return 0;
3812 
3813 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3814 					      prot->name);
3815 	if (!twsk_prot->twsk_slab_name)
3816 		return -ENOMEM;
3817 
3818 	twsk_prot->twsk_slab =
3819 		kmem_cache_create(twsk_prot->twsk_slab_name,
3820 				  twsk_prot->twsk_obj_size, 0,
3821 				  SLAB_ACCOUNT | prot->slab_flags,
3822 				  NULL);
3823 	if (!twsk_prot->twsk_slab) {
3824 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3825 			prot->name);
3826 		return -ENOMEM;
3827 	}
3828 
3829 	return 0;
3830 }
3831 
3832 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3833 {
3834 	if (!rsk_prot)
3835 		return;
3836 	kfree(rsk_prot->slab_name);
3837 	rsk_prot->slab_name = NULL;
3838 	kmem_cache_destroy(rsk_prot->slab);
3839 	rsk_prot->slab = NULL;
3840 }
3841 
3842 static int req_prot_init(const struct proto *prot)
3843 {
3844 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3845 
3846 	if (!rsk_prot)
3847 		return 0;
3848 
3849 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3850 					prot->name);
3851 	if (!rsk_prot->slab_name)
3852 		return -ENOMEM;
3853 
3854 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3855 					   rsk_prot->obj_size, 0,
3856 					   SLAB_ACCOUNT | prot->slab_flags,
3857 					   NULL);
3858 
3859 	if (!rsk_prot->slab) {
3860 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3861 			prot->name);
3862 		return -ENOMEM;
3863 	}
3864 	return 0;
3865 }
3866 
3867 int proto_register(struct proto *prot, int alloc_slab)
3868 {
3869 	int ret = -ENOBUFS;
3870 
3871 	if (prot->memory_allocated && !prot->sysctl_mem) {
3872 		pr_err("%s: missing sysctl_mem\n", prot->name);
3873 		return -EINVAL;
3874 	}
3875 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3876 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3877 		return -EINVAL;
3878 	}
3879 	if (alloc_slab) {
3880 		prot->slab = kmem_cache_create_usercopy(prot->name,
3881 					prot->obj_size, 0,
3882 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3883 					prot->slab_flags,
3884 					prot->useroffset, prot->usersize,
3885 					NULL);
3886 
3887 		if (prot->slab == NULL) {
3888 			pr_crit("%s: Can't create sock SLAB cache!\n",
3889 				prot->name);
3890 			goto out;
3891 		}
3892 
3893 		if (req_prot_init(prot))
3894 			goto out_free_request_sock_slab;
3895 
3896 		if (tw_prot_init(prot))
3897 			goto out_free_timewait_sock_slab;
3898 	}
3899 
3900 	mutex_lock(&proto_list_mutex);
3901 	ret = assign_proto_idx(prot);
3902 	if (ret) {
3903 		mutex_unlock(&proto_list_mutex);
3904 		goto out_free_timewait_sock_slab;
3905 	}
3906 	list_add(&prot->node, &proto_list);
3907 	mutex_unlock(&proto_list_mutex);
3908 	return ret;
3909 
3910 out_free_timewait_sock_slab:
3911 	if (alloc_slab)
3912 		tw_prot_cleanup(prot->twsk_prot);
3913 out_free_request_sock_slab:
3914 	if (alloc_slab) {
3915 		req_prot_cleanup(prot->rsk_prot);
3916 
3917 		kmem_cache_destroy(prot->slab);
3918 		prot->slab = NULL;
3919 	}
3920 out:
3921 	return ret;
3922 }
3923 EXPORT_SYMBOL(proto_register);
3924 
3925 void proto_unregister(struct proto *prot)
3926 {
3927 	mutex_lock(&proto_list_mutex);
3928 	release_proto_idx(prot);
3929 	list_del(&prot->node);
3930 	mutex_unlock(&proto_list_mutex);
3931 
3932 	kmem_cache_destroy(prot->slab);
3933 	prot->slab = NULL;
3934 
3935 	req_prot_cleanup(prot->rsk_prot);
3936 	tw_prot_cleanup(prot->twsk_prot);
3937 }
3938 EXPORT_SYMBOL(proto_unregister);
3939 
3940 int sock_load_diag_module(int family, int protocol)
3941 {
3942 	if (!protocol) {
3943 		if (!sock_is_registered(family))
3944 			return -ENOENT;
3945 
3946 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3947 				      NETLINK_SOCK_DIAG, family);
3948 	}
3949 
3950 #ifdef CONFIG_INET
3951 	if (family == AF_INET &&
3952 	    protocol != IPPROTO_RAW &&
3953 	    protocol < MAX_INET_PROTOS &&
3954 	    !rcu_access_pointer(inet_protos[protocol]))
3955 		return -ENOENT;
3956 #endif
3957 
3958 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3959 			      NETLINK_SOCK_DIAG, family, protocol);
3960 }
3961 EXPORT_SYMBOL(sock_load_diag_module);
3962 
3963 #ifdef CONFIG_PROC_FS
3964 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3965 	__acquires(proto_list_mutex)
3966 {
3967 	mutex_lock(&proto_list_mutex);
3968 	return seq_list_start_head(&proto_list, *pos);
3969 }
3970 
3971 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3972 {
3973 	return seq_list_next(v, &proto_list, pos);
3974 }
3975 
3976 static void proto_seq_stop(struct seq_file *seq, void *v)
3977 	__releases(proto_list_mutex)
3978 {
3979 	mutex_unlock(&proto_list_mutex);
3980 }
3981 
3982 static char proto_method_implemented(const void *method)
3983 {
3984 	return method == NULL ? 'n' : 'y';
3985 }
3986 static long sock_prot_memory_allocated(struct proto *proto)
3987 {
3988 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3989 }
3990 
3991 static const char *sock_prot_memory_pressure(struct proto *proto)
3992 {
3993 	return proto->memory_pressure != NULL ?
3994 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3995 }
3996 
3997 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3998 {
3999 
4000 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4001 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4002 		   proto->name,
4003 		   proto->obj_size,
4004 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4005 		   sock_prot_memory_allocated(proto),
4006 		   sock_prot_memory_pressure(proto),
4007 		   proto->max_header,
4008 		   proto->slab == NULL ? "no" : "yes",
4009 		   module_name(proto->owner),
4010 		   proto_method_implemented(proto->close),
4011 		   proto_method_implemented(proto->connect),
4012 		   proto_method_implemented(proto->disconnect),
4013 		   proto_method_implemented(proto->accept),
4014 		   proto_method_implemented(proto->ioctl),
4015 		   proto_method_implemented(proto->init),
4016 		   proto_method_implemented(proto->destroy),
4017 		   proto_method_implemented(proto->shutdown),
4018 		   proto_method_implemented(proto->setsockopt),
4019 		   proto_method_implemented(proto->getsockopt),
4020 		   proto_method_implemented(proto->sendmsg),
4021 		   proto_method_implemented(proto->recvmsg),
4022 		   proto_method_implemented(proto->sendpage),
4023 		   proto_method_implemented(proto->bind),
4024 		   proto_method_implemented(proto->backlog_rcv),
4025 		   proto_method_implemented(proto->hash),
4026 		   proto_method_implemented(proto->unhash),
4027 		   proto_method_implemented(proto->get_port),
4028 		   proto_method_implemented(proto->enter_memory_pressure));
4029 }
4030 
4031 static int proto_seq_show(struct seq_file *seq, void *v)
4032 {
4033 	if (v == &proto_list)
4034 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4035 			   "protocol",
4036 			   "size",
4037 			   "sockets",
4038 			   "memory",
4039 			   "press",
4040 			   "maxhdr",
4041 			   "slab",
4042 			   "module",
4043 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4044 	else
4045 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4046 	return 0;
4047 }
4048 
4049 static const struct seq_operations proto_seq_ops = {
4050 	.start  = proto_seq_start,
4051 	.next   = proto_seq_next,
4052 	.stop   = proto_seq_stop,
4053 	.show   = proto_seq_show,
4054 };
4055 
4056 static __net_init int proto_init_net(struct net *net)
4057 {
4058 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4059 			sizeof(struct seq_net_private)))
4060 		return -ENOMEM;
4061 
4062 	return 0;
4063 }
4064 
4065 static __net_exit void proto_exit_net(struct net *net)
4066 {
4067 	remove_proc_entry("protocols", net->proc_net);
4068 }
4069 
4070 
4071 static __net_initdata struct pernet_operations proto_net_ops = {
4072 	.init = proto_init_net,
4073 	.exit = proto_exit_net,
4074 };
4075 
4076 static int __init proto_init(void)
4077 {
4078 	return register_pernet_subsys(&proto_net_ops);
4079 }
4080 
4081 subsys_initcall(proto_init);
4082 
4083 #endif /* PROC_FS */
4084 
4085 #ifdef CONFIG_NET_RX_BUSY_POLL
4086 bool sk_busy_loop_end(void *p, unsigned long start_time)
4087 {
4088 	struct sock *sk = p;
4089 
4090 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4091 	       sk_busy_loop_timeout(sk, start_time);
4092 }
4093 EXPORT_SYMBOL(sk_busy_loop_end);
4094 #endif /* CONFIG_NET_RX_BUSY_POLL */
4095 
4096 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4097 {
4098 	if (!sk->sk_prot->bind_add)
4099 		return -EOPNOTSUPP;
4100 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4101 }
4102 EXPORT_SYMBOL(sock_bind_add);
4103