xref: /openbmc/linux/net/core/sock.c (revision 6aeadf78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <asm/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/init.h>
111 #include <linux/highmem.h>
112 #include <linux/user_namespace.h>
113 #include <linux/static_key.h>
114 #include <linux/memcontrol.h>
115 #include <linux/prefetch.h>
116 #include <linux/compat.h>
117 
118 #include <linux/uaccess.h>
119 
120 #include <linux/netdevice.h>
121 #include <net/protocol.h>
122 #include <linux/skbuff.h>
123 #include <net/net_namespace.h>
124 #include <net/request_sock.h>
125 #include <net/sock.h>
126 #include <linux/net_tstamp.h>
127 #include <net/xfrm.h>
128 #include <linux/ipsec.h>
129 #include <net/cls_cgroup.h>
130 #include <net/netprio_cgroup.h>
131 #include <linux/sock_diag.h>
132 
133 #include <linux/filter.h>
134 #include <net/sock_reuseport.h>
135 #include <net/bpf_sk_storage.h>
136 
137 #include <trace/events/sock.h>
138 
139 #include <net/tcp.h>
140 #include <net/busy_poll.h>
141 
142 #include <linux/ethtool.h>
143 
144 #include "dev.h"
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_def_write_space_wfree(struct sock *sk);
150 static void sock_def_write_space(struct sock *sk);
151 
152 /**
153  * sk_ns_capable - General socket capability test
154  * @sk: Socket to use a capability on or through
155  * @user_ns: The user namespace of the capability to use
156  * @cap: The capability to use
157  *
158  * Test to see if the opener of the socket had when the socket was
159  * created and the current process has the capability @cap in the user
160  * namespace @user_ns.
161  */
162 bool sk_ns_capable(const struct sock *sk,
163 		   struct user_namespace *user_ns, int cap)
164 {
165 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
166 		ns_capable(user_ns, cap);
167 }
168 EXPORT_SYMBOL(sk_ns_capable);
169 
170 /**
171  * sk_capable - Socket global capability test
172  * @sk: Socket to use a capability on or through
173  * @cap: The global capability to use
174  *
175  * Test to see if the opener of the socket had when the socket was
176  * created and the current process has the capability @cap in all user
177  * namespaces.
178  */
179 bool sk_capable(const struct sock *sk, int cap)
180 {
181 	return sk_ns_capable(sk, &init_user_ns, cap);
182 }
183 EXPORT_SYMBOL(sk_capable);
184 
185 /**
186  * sk_net_capable - Network namespace socket capability test
187  * @sk: Socket to use a capability on or through
188  * @cap: The capability to use
189  *
190  * Test to see if the opener of the socket had when the socket was created
191  * and the current process has the capability @cap over the network namespace
192  * the socket is a member of.
193  */
194 bool sk_net_capable(const struct sock *sk, int cap)
195 {
196 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
197 }
198 EXPORT_SYMBOL(sk_net_capable);
199 
200 /*
201  * Each address family might have different locking rules, so we have
202  * one slock key per address family and separate keys for internal and
203  * userspace sockets.
204  */
205 static struct lock_class_key af_family_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_keys[AF_MAX];
207 static struct lock_class_key af_family_slock_keys[AF_MAX];
208 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
209 
210 /*
211  * Make lock validator output more readable. (we pre-construct these
212  * strings build-time, so that runtime initialization of socket
213  * locks is fast):
214  */
215 
216 #define _sock_locks(x)						  \
217   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
218   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
219   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
220   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
221   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
222   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
223   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
224   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
225   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
226   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
227   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
228   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
229   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
230   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
231   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
232   x "AF_MCTP"  , \
233   x "AF_MAX"
234 
235 static const char *const af_family_key_strings[AF_MAX+1] = {
236 	_sock_locks("sk_lock-")
237 };
238 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
239 	_sock_locks("slock-")
240 };
241 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
242 	_sock_locks("clock-")
243 };
244 
245 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
246 	_sock_locks("k-sk_lock-")
247 };
248 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
249 	_sock_locks("k-slock-")
250 };
251 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
252 	_sock_locks("k-clock-")
253 };
254 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
255 	_sock_locks("rlock-")
256 };
257 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
258 	_sock_locks("wlock-")
259 };
260 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
261 	_sock_locks("elock-")
262 };
263 
264 /*
265  * sk_callback_lock and sk queues locking rules are per-address-family,
266  * so split the lock classes by using a per-AF key:
267  */
268 static struct lock_class_key af_callback_keys[AF_MAX];
269 static struct lock_class_key af_rlock_keys[AF_MAX];
270 static struct lock_class_key af_wlock_keys[AF_MAX];
271 static struct lock_class_key af_elock_keys[AF_MAX];
272 static struct lock_class_key af_kern_callback_keys[AF_MAX];
273 
274 /* Run time adjustable parameters. */
275 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
276 EXPORT_SYMBOL(sysctl_wmem_max);
277 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
278 EXPORT_SYMBOL(sysctl_rmem_max);
279 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
280 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
281 
282 /* Maximal space eaten by iovec or ancillary data plus some space */
283 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
284 EXPORT_SYMBOL(sysctl_optmem_max);
285 
286 int sysctl_tstamp_allow_data __read_mostly = 1;
287 
288 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
289 EXPORT_SYMBOL_GPL(memalloc_socks_key);
290 
291 /**
292  * sk_set_memalloc - sets %SOCK_MEMALLOC
293  * @sk: socket to set it on
294  *
295  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
296  * It's the responsibility of the admin to adjust min_free_kbytes
297  * to meet the requirements
298  */
299 void sk_set_memalloc(struct sock *sk)
300 {
301 	sock_set_flag(sk, SOCK_MEMALLOC);
302 	sk->sk_allocation |= __GFP_MEMALLOC;
303 	static_branch_inc(&memalloc_socks_key);
304 }
305 EXPORT_SYMBOL_GPL(sk_set_memalloc);
306 
307 void sk_clear_memalloc(struct sock *sk)
308 {
309 	sock_reset_flag(sk, SOCK_MEMALLOC);
310 	sk->sk_allocation &= ~__GFP_MEMALLOC;
311 	static_branch_dec(&memalloc_socks_key);
312 
313 	/*
314 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
315 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
316 	 * it has rmem allocations due to the last swapfile being deactivated
317 	 * but there is a risk that the socket is unusable due to exceeding
318 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
319 	 */
320 	sk_mem_reclaim(sk);
321 }
322 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
323 
324 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
325 {
326 	int ret;
327 	unsigned int noreclaim_flag;
328 
329 	/* these should have been dropped before queueing */
330 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
331 
332 	noreclaim_flag = memalloc_noreclaim_save();
333 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
334 				 tcp_v6_do_rcv,
335 				 tcp_v4_do_rcv,
336 				 sk, skb);
337 	memalloc_noreclaim_restore(noreclaim_flag);
338 
339 	return ret;
340 }
341 EXPORT_SYMBOL(__sk_backlog_rcv);
342 
343 void sk_error_report(struct sock *sk)
344 {
345 	sk->sk_error_report(sk);
346 
347 	switch (sk->sk_family) {
348 	case AF_INET:
349 		fallthrough;
350 	case AF_INET6:
351 		trace_inet_sk_error_report(sk);
352 		break;
353 	default:
354 		break;
355 	}
356 }
357 EXPORT_SYMBOL(sk_error_report);
358 
359 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
360 {
361 	struct __kernel_sock_timeval tv;
362 
363 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
364 		tv.tv_sec = 0;
365 		tv.tv_usec = 0;
366 	} else {
367 		tv.tv_sec = timeo / HZ;
368 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
369 	}
370 
371 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
372 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
373 		*(struct old_timeval32 *)optval = tv32;
374 		return sizeof(tv32);
375 	}
376 
377 	if (old_timeval) {
378 		struct __kernel_old_timeval old_tv;
379 		old_tv.tv_sec = tv.tv_sec;
380 		old_tv.tv_usec = tv.tv_usec;
381 		*(struct __kernel_old_timeval *)optval = old_tv;
382 		return sizeof(old_tv);
383 	}
384 
385 	*(struct __kernel_sock_timeval *)optval = tv;
386 	return sizeof(tv);
387 }
388 EXPORT_SYMBOL(sock_get_timeout);
389 
390 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
391 			   sockptr_t optval, int optlen, bool old_timeval)
392 {
393 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
394 		struct old_timeval32 tv32;
395 
396 		if (optlen < sizeof(tv32))
397 			return -EINVAL;
398 
399 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
400 			return -EFAULT;
401 		tv->tv_sec = tv32.tv_sec;
402 		tv->tv_usec = tv32.tv_usec;
403 	} else if (old_timeval) {
404 		struct __kernel_old_timeval old_tv;
405 
406 		if (optlen < sizeof(old_tv))
407 			return -EINVAL;
408 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
409 			return -EFAULT;
410 		tv->tv_sec = old_tv.tv_sec;
411 		tv->tv_usec = old_tv.tv_usec;
412 	} else {
413 		if (optlen < sizeof(*tv))
414 			return -EINVAL;
415 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
416 			return -EFAULT;
417 	}
418 
419 	return 0;
420 }
421 EXPORT_SYMBOL(sock_copy_user_timeval);
422 
423 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
424 			    bool old_timeval)
425 {
426 	struct __kernel_sock_timeval tv;
427 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
428 
429 	if (err)
430 		return err;
431 
432 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
433 		return -EDOM;
434 
435 	if (tv.tv_sec < 0) {
436 		static int warned __read_mostly;
437 
438 		*timeo_p = 0;
439 		if (warned < 10 && net_ratelimit()) {
440 			warned++;
441 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
442 				__func__, current->comm, task_pid_nr(current));
443 		}
444 		return 0;
445 	}
446 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
447 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
448 		return 0;
449 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
450 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
451 	return 0;
452 }
453 
454 static bool sock_needs_netstamp(const struct sock *sk)
455 {
456 	switch (sk->sk_family) {
457 	case AF_UNSPEC:
458 	case AF_UNIX:
459 		return false;
460 	default:
461 		return true;
462 	}
463 }
464 
465 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
466 {
467 	if (sk->sk_flags & flags) {
468 		sk->sk_flags &= ~flags;
469 		if (sock_needs_netstamp(sk) &&
470 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
471 			net_disable_timestamp();
472 	}
473 }
474 
475 
476 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 {
478 	unsigned long flags;
479 	struct sk_buff_head *list = &sk->sk_receive_queue;
480 
481 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
482 		atomic_inc(&sk->sk_drops);
483 		trace_sock_rcvqueue_full(sk, skb);
484 		return -ENOMEM;
485 	}
486 
487 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
488 		atomic_inc(&sk->sk_drops);
489 		return -ENOBUFS;
490 	}
491 
492 	skb->dev = NULL;
493 	skb_set_owner_r(skb, sk);
494 
495 	/* we escape from rcu protected region, make sure we dont leak
496 	 * a norefcounted dst
497 	 */
498 	skb_dst_force(skb);
499 
500 	spin_lock_irqsave(&list->lock, flags);
501 	sock_skb_set_dropcount(sk, skb);
502 	__skb_queue_tail(list, skb);
503 	spin_unlock_irqrestore(&list->lock, flags);
504 
505 	if (!sock_flag(sk, SOCK_DEAD))
506 		sk->sk_data_ready(sk);
507 	return 0;
508 }
509 EXPORT_SYMBOL(__sock_queue_rcv_skb);
510 
511 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
512 			      enum skb_drop_reason *reason)
513 {
514 	enum skb_drop_reason drop_reason;
515 	int err;
516 
517 	err = sk_filter(sk, skb);
518 	if (err) {
519 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
520 		goto out;
521 	}
522 	err = __sock_queue_rcv_skb(sk, skb);
523 	switch (err) {
524 	case -ENOMEM:
525 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
526 		break;
527 	case -ENOBUFS:
528 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
529 		break;
530 	default:
531 		drop_reason = SKB_NOT_DROPPED_YET;
532 		break;
533 	}
534 out:
535 	if (reason)
536 		*reason = drop_reason;
537 	return err;
538 }
539 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
540 
541 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
542 		     const int nested, unsigned int trim_cap, bool refcounted)
543 {
544 	int rc = NET_RX_SUCCESS;
545 
546 	if (sk_filter_trim_cap(sk, skb, trim_cap))
547 		goto discard_and_relse;
548 
549 	skb->dev = NULL;
550 
551 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
552 		atomic_inc(&sk->sk_drops);
553 		goto discard_and_relse;
554 	}
555 	if (nested)
556 		bh_lock_sock_nested(sk);
557 	else
558 		bh_lock_sock(sk);
559 	if (!sock_owned_by_user(sk)) {
560 		/*
561 		 * trylock + unlock semantics:
562 		 */
563 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
564 
565 		rc = sk_backlog_rcv(sk, skb);
566 
567 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
568 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
569 		bh_unlock_sock(sk);
570 		atomic_inc(&sk->sk_drops);
571 		goto discard_and_relse;
572 	}
573 
574 	bh_unlock_sock(sk);
575 out:
576 	if (refcounted)
577 		sock_put(sk);
578 	return rc;
579 discard_and_relse:
580 	kfree_skb(skb);
581 	goto out;
582 }
583 EXPORT_SYMBOL(__sk_receive_skb);
584 
585 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
586 							  u32));
587 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
588 							   u32));
589 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
590 {
591 	struct dst_entry *dst = __sk_dst_get(sk);
592 
593 	if (dst && dst->obsolete &&
594 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
595 			       dst, cookie) == NULL) {
596 		sk_tx_queue_clear(sk);
597 		sk->sk_dst_pending_confirm = 0;
598 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
599 		dst_release(dst);
600 		return NULL;
601 	}
602 
603 	return dst;
604 }
605 EXPORT_SYMBOL(__sk_dst_check);
606 
607 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 	struct dst_entry *dst = sk_dst_get(sk);
610 
611 	if (dst && dst->obsolete &&
612 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 			       dst, cookie) == NULL) {
614 		sk_dst_reset(sk);
615 		dst_release(dst);
616 		return NULL;
617 	}
618 
619 	return dst;
620 }
621 EXPORT_SYMBOL(sk_dst_check);
622 
623 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
624 {
625 	int ret = -ENOPROTOOPT;
626 #ifdef CONFIG_NETDEVICES
627 	struct net *net = sock_net(sk);
628 
629 	/* Sorry... */
630 	ret = -EPERM;
631 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
632 		goto out;
633 
634 	ret = -EINVAL;
635 	if (ifindex < 0)
636 		goto out;
637 
638 	/* Paired with all READ_ONCE() done locklessly. */
639 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
640 
641 	if (sk->sk_prot->rehash)
642 		sk->sk_prot->rehash(sk);
643 	sk_dst_reset(sk);
644 
645 	ret = 0;
646 
647 out:
648 #endif
649 
650 	return ret;
651 }
652 
653 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
654 {
655 	int ret;
656 
657 	if (lock_sk)
658 		lock_sock(sk);
659 	ret = sock_bindtoindex_locked(sk, ifindex);
660 	if (lock_sk)
661 		release_sock(sk);
662 
663 	return ret;
664 }
665 EXPORT_SYMBOL(sock_bindtoindex);
666 
667 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
668 {
669 	int ret = -ENOPROTOOPT;
670 #ifdef CONFIG_NETDEVICES
671 	struct net *net = sock_net(sk);
672 	char devname[IFNAMSIZ];
673 	int index;
674 
675 	ret = -EINVAL;
676 	if (optlen < 0)
677 		goto out;
678 
679 	/* Bind this socket to a particular device like "eth0",
680 	 * as specified in the passed interface name. If the
681 	 * name is "" or the option length is zero the socket
682 	 * is not bound.
683 	 */
684 	if (optlen > IFNAMSIZ - 1)
685 		optlen = IFNAMSIZ - 1;
686 	memset(devname, 0, sizeof(devname));
687 
688 	ret = -EFAULT;
689 	if (copy_from_sockptr(devname, optval, optlen))
690 		goto out;
691 
692 	index = 0;
693 	if (devname[0] != '\0') {
694 		struct net_device *dev;
695 
696 		rcu_read_lock();
697 		dev = dev_get_by_name_rcu(net, devname);
698 		if (dev)
699 			index = dev->ifindex;
700 		rcu_read_unlock();
701 		ret = -ENODEV;
702 		if (!dev)
703 			goto out;
704 	}
705 
706 	sockopt_lock_sock(sk);
707 	ret = sock_bindtoindex_locked(sk, index);
708 	sockopt_release_sock(sk);
709 out:
710 #endif
711 
712 	return ret;
713 }
714 
715 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
716 				sockptr_t optlen, int len)
717 {
718 	int ret = -ENOPROTOOPT;
719 #ifdef CONFIG_NETDEVICES
720 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
721 	struct net *net = sock_net(sk);
722 	char devname[IFNAMSIZ];
723 
724 	if (bound_dev_if == 0) {
725 		len = 0;
726 		goto zero;
727 	}
728 
729 	ret = -EINVAL;
730 	if (len < IFNAMSIZ)
731 		goto out;
732 
733 	ret = netdev_get_name(net, devname, bound_dev_if);
734 	if (ret)
735 		goto out;
736 
737 	len = strlen(devname) + 1;
738 
739 	ret = -EFAULT;
740 	if (copy_to_sockptr(optval, devname, len))
741 		goto out;
742 
743 zero:
744 	ret = -EFAULT;
745 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
746 		goto out;
747 
748 	ret = 0;
749 
750 out:
751 #endif
752 
753 	return ret;
754 }
755 
756 bool sk_mc_loop(struct sock *sk)
757 {
758 	if (dev_recursion_level())
759 		return false;
760 	if (!sk)
761 		return true;
762 	switch (sk->sk_family) {
763 	case AF_INET:
764 		return inet_sk(sk)->mc_loop;
765 #if IS_ENABLED(CONFIG_IPV6)
766 	case AF_INET6:
767 		return inet6_sk(sk)->mc_loop;
768 #endif
769 	}
770 	WARN_ON_ONCE(1);
771 	return true;
772 }
773 EXPORT_SYMBOL(sk_mc_loop);
774 
775 void sock_set_reuseaddr(struct sock *sk)
776 {
777 	lock_sock(sk);
778 	sk->sk_reuse = SK_CAN_REUSE;
779 	release_sock(sk);
780 }
781 EXPORT_SYMBOL(sock_set_reuseaddr);
782 
783 void sock_set_reuseport(struct sock *sk)
784 {
785 	lock_sock(sk);
786 	sk->sk_reuseport = true;
787 	release_sock(sk);
788 }
789 EXPORT_SYMBOL(sock_set_reuseport);
790 
791 void sock_no_linger(struct sock *sk)
792 {
793 	lock_sock(sk);
794 	sk->sk_lingertime = 0;
795 	sock_set_flag(sk, SOCK_LINGER);
796 	release_sock(sk);
797 }
798 EXPORT_SYMBOL(sock_no_linger);
799 
800 void sock_set_priority(struct sock *sk, u32 priority)
801 {
802 	lock_sock(sk);
803 	sk->sk_priority = priority;
804 	release_sock(sk);
805 }
806 EXPORT_SYMBOL(sock_set_priority);
807 
808 void sock_set_sndtimeo(struct sock *sk, s64 secs)
809 {
810 	lock_sock(sk);
811 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
812 		sk->sk_sndtimeo = secs * HZ;
813 	else
814 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
815 	release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_set_sndtimeo);
818 
819 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
820 {
821 	if (val)  {
822 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
823 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
824 		sock_set_flag(sk, SOCK_RCVTSTAMP);
825 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
826 	} else {
827 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
828 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
829 	}
830 }
831 
832 void sock_enable_timestamps(struct sock *sk)
833 {
834 	lock_sock(sk);
835 	__sock_set_timestamps(sk, true, false, true);
836 	release_sock(sk);
837 }
838 EXPORT_SYMBOL(sock_enable_timestamps);
839 
840 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
841 {
842 	switch (optname) {
843 	case SO_TIMESTAMP_OLD:
844 		__sock_set_timestamps(sk, valbool, false, false);
845 		break;
846 	case SO_TIMESTAMP_NEW:
847 		__sock_set_timestamps(sk, valbool, true, false);
848 		break;
849 	case SO_TIMESTAMPNS_OLD:
850 		__sock_set_timestamps(sk, valbool, false, true);
851 		break;
852 	case SO_TIMESTAMPNS_NEW:
853 		__sock_set_timestamps(sk, valbool, true, true);
854 		break;
855 	}
856 }
857 
858 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
859 {
860 	struct net *net = sock_net(sk);
861 	struct net_device *dev = NULL;
862 	bool match = false;
863 	int *vclock_index;
864 	int i, num;
865 
866 	if (sk->sk_bound_dev_if)
867 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
868 
869 	if (!dev) {
870 		pr_err("%s: sock not bind to device\n", __func__);
871 		return -EOPNOTSUPP;
872 	}
873 
874 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
875 	dev_put(dev);
876 
877 	for (i = 0; i < num; i++) {
878 		if (*(vclock_index + i) == phc_index) {
879 			match = true;
880 			break;
881 		}
882 	}
883 
884 	if (num > 0)
885 		kfree(vclock_index);
886 
887 	if (!match)
888 		return -EINVAL;
889 
890 	sk->sk_bind_phc = phc_index;
891 
892 	return 0;
893 }
894 
895 int sock_set_timestamping(struct sock *sk, int optname,
896 			  struct so_timestamping timestamping)
897 {
898 	int val = timestamping.flags;
899 	int ret;
900 
901 	if (val & ~SOF_TIMESTAMPING_MASK)
902 		return -EINVAL;
903 
904 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
905 	    !(val & SOF_TIMESTAMPING_OPT_ID))
906 		return -EINVAL;
907 
908 	if (val & SOF_TIMESTAMPING_OPT_ID &&
909 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
910 		if (sk_is_tcp(sk)) {
911 			if ((1 << sk->sk_state) &
912 			    (TCPF_CLOSE | TCPF_LISTEN))
913 				return -EINVAL;
914 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
915 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
916 			else
917 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
918 		} else {
919 			atomic_set(&sk->sk_tskey, 0);
920 		}
921 	}
922 
923 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
924 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
925 		return -EINVAL;
926 
927 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
928 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
929 		if (ret)
930 			return ret;
931 	}
932 
933 	sk->sk_tsflags = val;
934 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
935 
936 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
937 		sock_enable_timestamp(sk,
938 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
939 	else
940 		sock_disable_timestamp(sk,
941 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
942 	return 0;
943 }
944 
945 void sock_set_keepalive(struct sock *sk)
946 {
947 	lock_sock(sk);
948 	if (sk->sk_prot->keepalive)
949 		sk->sk_prot->keepalive(sk, true);
950 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
951 	release_sock(sk);
952 }
953 EXPORT_SYMBOL(sock_set_keepalive);
954 
955 static void __sock_set_rcvbuf(struct sock *sk, int val)
956 {
957 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
958 	 * as a negative value.
959 	 */
960 	val = min_t(int, val, INT_MAX / 2);
961 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
962 
963 	/* We double it on the way in to account for "struct sk_buff" etc.
964 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
965 	 * will allow that much actual data to be received on that socket.
966 	 *
967 	 * Applications are unaware that "struct sk_buff" and other overheads
968 	 * allocate from the receive buffer during socket buffer allocation.
969 	 *
970 	 * And after considering the possible alternatives, returning the value
971 	 * we actually used in getsockopt is the most desirable behavior.
972 	 */
973 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
974 }
975 
976 void sock_set_rcvbuf(struct sock *sk, int val)
977 {
978 	lock_sock(sk);
979 	__sock_set_rcvbuf(sk, val);
980 	release_sock(sk);
981 }
982 EXPORT_SYMBOL(sock_set_rcvbuf);
983 
984 static void __sock_set_mark(struct sock *sk, u32 val)
985 {
986 	if (val != sk->sk_mark) {
987 		sk->sk_mark = val;
988 		sk_dst_reset(sk);
989 	}
990 }
991 
992 void sock_set_mark(struct sock *sk, u32 val)
993 {
994 	lock_sock(sk);
995 	__sock_set_mark(sk, val);
996 	release_sock(sk);
997 }
998 EXPORT_SYMBOL(sock_set_mark);
999 
1000 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1001 {
1002 	/* Round down bytes to multiple of pages */
1003 	bytes = round_down(bytes, PAGE_SIZE);
1004 
1005 	WARN_ON(bytes > sk->sk_reserved_mem);
1006 	sk->sk_reserved_mem -= bytes;
1007 	sk_mem_reclaim(sk);
1008 }
1009 
1010 static int sock_reserve_memory(struct sock *sk, int bytes)
1011 {
1012 	long allocated;
1013 	bool charged;
1014 	int pages;
1015 
1016 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1017 		return -EOPNOTSUPP;
1018 
1019 	if (!bytes)
1020 		return 0;
1021 
1022 	pages = sk_mem_pages(bytes);
1023 
1024 	/* pre-charge to memcg */
1025 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1026 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1027 	if (!charged)
1028 		return -ENOMEM;
1029 
1030 	/* pre-charge to forward_alloc */
1031 	sk_memory_allocated_add(sk, pages);
1032 	allocated = sk_memory_allocated(sk);
1033 	/* If the system goes into memory pressure with this
1034 	 * precharge, give up and return error.
1035 	 */
1036 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1037 		sk_memory_allocated_sub(sk, pages);
1038 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1039 		return -ENOMEM;
1040 	}
1041 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1042 
1043 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1044 
1045 	return 0;
1046 }
1047 
1048 void sockopt_lock_sock(struct sock *sk)
1049 {
1050 	/* When current->bpf_ctx is set, the setsockopt is called from
1051 	 * a bpf prog.  bpf has ensured the sk lock has been
1052 	 * acquired before calling setsockopt().
1053 	 */
1054 	if (has_current_bpf_ctx())
1055 		return;
1056 
1057 	lock_sock(sk);
1058 }
1059 EXPORT_SYMBOL(sockopt_lock_sock);
1060 
1061 void sockopt_release_sock(struct sock *sk)
1062 {
1063 	if (has_current_bpf_ctx())
1064 		return;
1065 
1066 	release_sock(sk);
1067 }
1068 EXPORT_SYMBOL(sockopt_release_sock);
1069 
1070 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1071 {
1072 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1073 }
1074 EXPORT_SYMBOL(sockopt_ns_capable);
1075 
1076 bool sockopt_capable(int cap)
1077 {
1078 	return has_current_bpf_ctx() || capable(cap);
1079 }
1080 EXPORT_SYMBOL(sockopt_capable);
1081 
1082 /*
1083  *	This is meant for all protocols to use and covers goings on
1084  *	at the socket level. Everything here is generic.
1085  */
1086 
1087 int sk_setsockopt(struct sock *sk, int level, int optname,
1088 		  sockptr_t optval, unsigned int optlen)
1089 {
1090 	struct so_timestamping timestamping;
1091 	struct socket *sock = sk->sk_socket;
1092 	struct sock_txtime sk_txtime;
1093 	int val;
1094 	int valbool;
1095 	struct linger ling;
1096 	int ret = 0;
1097 
1098 	/*
1099 	 *	Options without arguments
1100 	 */
1101 
1102 	if (optname == SO_BINDTODEVICE)
1103 		return sock_setbindtodevice(sk, optval, optlen);
1104 
1105 	if (optlen < sizeof(int))
1106 		return -EINVAL;
1107 
1108 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1109 		return -EFAULT;
1110 
1111 	valbool = val ? 1 : 0;
1112 
1113 	sockopt_lock_sock(sk);
1114 
1115 	switch (optname) {
1116 	case SO_DEBUG:
1117 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1118 			ret = -EACCES;
1119 		else
1120 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1121 		break;
1122 	case SO_REUSEADDR:
1123 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1124 		break;
1125 	case SO_REUSEPORT:
1126 		sk->sk_reuseport = valbool;
1127 		break;
1128 	case SO_TYPE:
1129 	case SO_PROTOCOL:
1130 	case SO_DOMAIN:
1131 	case SO_ERROR:
1132 		ret = -ENOPROTOOPT;
1133 		break;
1134 	case SO_DONTROUTE:
1135 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1136 		sk_dst_reset(sk);
1137 		break;
1138 	case SO_BROADCAST:
1139 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1140 		break;
1141 	case SO_SNDBUF:
1142 		/* Don't error on this BSD doesn't and if you think
1143 		 * about it this is right. Otherwise apps have to
1144 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1145 		 * are treated in BSD as hints
1146 		 */
1147 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1148 set_sndbuf:
1149 		/* Ensure val * 2 fits into an int, to prevent max_t()
1150 		 * from treating it as a negative value.
1151 		 */
1152 		val = min_t(int, val, INT_MAX / 2);
1153 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1154 		WRITE_ONCE(sk->sk_sndbuf,
1155 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1156 		/* Wake up sending tasks if we upped the value. */
1157 		sk->sk_write_space(sk);
1158 		break;
1159 
1160 	case SO_SNDBUFFORCE:
1161 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1162 			ret = -EPERM;
1163 			break;
1164 		}
1165 
1166 		/* No negative values (to prevent underflow, as val will be
1167 		 * multiplied by 2).
1168 		 */
1169 		if (val < 0)
1170 			val = 0;
1171 		goto set_sndbuf;
1172 
1173 	case SO_RCVBUF:
1174 		/* Don't error on this BSD doesn't and if you think
1175 		 * about it this is right. Otherwise apps have to
1176 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1177 		 * are treated in BSD as hints
1178 		 */
1179 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1180 		break;
1181 
1182 	case SO_RCVBUFFORCE:
1183 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1184 			ret = -EPERM;
1185 			break;
1186 		}
1187 
1188 		/* No negative values (to prevent underflow, as val will be
1189 		 * multiplied by 2).
1190 		 */
1191 		__sock_set_rcvbuf(sk, max(val, 0));
1192 		break;
1193 
1194 	case SO_KEEPALIVE:
1195 		if (sk->sk_prot->keepalive)
1196 			sk->sk_prot->keepalive(sk, valbool);
1197 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1198 		break;
1199 
1200 	case SO_OOBINLINE:
1201 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1202 		break;
1203 
1204 	case SO_NO_CHECK:
1205 		sk->sk_no_check_tx = valbool;
1206 		break;
1207 
1208 	case SO_PRIORITY:
1209 		if ((val >= 0 && val <= 6) ||
1210 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1211 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1212 			sk->sk_priority = val;
1213 		else
1214 			ret = -EPERM;
1215 		break;
1216 
1217 	case SO_LINGER:
1218 		if (optlen < sizeof(ling)) {
1219 			ret = -EINVAL;	/* 1003.1g */
1220 			break;
1221 		}
1222 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1223 			ret = -EFAULT;
1224 			break;
1225 		}
1226 		if (!ling.l_onoff)
1227 			sock_reset_flag(sk, SOCK_LINGER);
1228 		else {
1229 #if (BITS_PER_LONG == 32)
1230 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1231 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1232 			else
1233 #endif
1234 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1235 			sock_set_flag(sk, SOCK_LINGER);
1236 		}
1237 		break;
1238 
1239 	case SO_BSDCOMPAT:
1240 		break;
1241 
1242 	case SO_PASSCRED:
1243 		if (valbool)
1244 			set_bit(SOCK_PASSCRED, &sock->flags);
1245 		else
1246 			clear_bit(SOCK_PASSCRED, &sock->flags);
1247 		break;
1248 
1249 	case SO_TIMESTAMP_OLD:
1250 	case SO_TIMESTAMP_NEW:
1251 	case SO_TIMESTAMPNS_OLD:
1252 	case SO_TIMESTAMPNS_NEW:
1253 		sock_set_timestamp(sk, optname, valbool);
1254 		break;
1255 
1256 	case SO_TIMESTAMPING_NEW:
1257 	case SO_TIMESTAMPING_OLD:
1258 		if (optlen == sizeof(timestamping)) {
1259 			if (copy_from_sockptr(&timestamping, optval,
1260 					      sizeof(timestamping))) {
1261 				ret = -EFAULT;
1262 				break;
1263 			}
1264 		} else {
1265 			memset(&timestamping, 0, sizeof(timestamping));
1266 			timestamping.flags = val;
1267 		}
1268 		ret = sock_set_timestamping(sk, optname, timestamping);
1269 		break;
1270 
1271 	case SO_RCVLOWAT:
1272 		if (val < 0)
1273 			val = INT_MAX;
1274 		if (sock && sock->ops->set_rcvlowat)
1275 			ret = sock->ops->set_rcvlowat(sk, val);
1276 		else
1277 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1278 		break;
1279 
1280 	case SO_RCVTIMEO_OLD:
1281 	case SO_RCVTIMEO_NEW:
1282 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1283 				       optlen, optname == SO_RCVTIMEO_OLD);
1284 		break;
1285 
1286 	case SO_SNDTIMEO_OLD:
1287 	case SO_SNDTIMEO_NEW:
1288 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1289 				       optlen, optname == SO_SNDTIMEO_OLD);
1290 		break;
1291 
1292 	case SO_ATTACH_FILTER: {
1293 		struct sock_fprog fprog;
1294 
1295 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1296 		if (!ret)
1297 			ret = sk_attach_filter(&fprog, sk);
1298 		break;
1299 	}
1300 	case SO_ATTACH_BPF:
1301 		ret = -EINVAL;
1302 		if (optlen == sizeof(u32)) {
1303 			u32 ufd;
1304 
1305 			ret = -EFAULT;
1306 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1307 				break;
1308 
1309 			ret = sk_attach_bpf(ufd, sk);
1310 		}
1311 		break;
1312 
1313 	case SO_ATTACH_REUSEPORT_CBPF: {
1314 		struct sock_fprog fprog;
1315 
1316 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1317 		if (!ret)
1318 			ret = sk_reuseport_attach_filter(&fprog, sk);
1319 		break;
1320 	}
1321 	case SO_ATTACH_REUSEPORT_EBPF:
1322 		ret = -EINVAL;
1323 		if (optlen == sizeof(u32)) {
1324 			u32 ufd;
1325 
1326 			ret = -EFAULT;
1327 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1328 				break;
1329 
1330 			ret = sk_reuseport_attach_bpf(ufd, sk);
1331 		}
1332 		break;
1333 
1334 	case SO_DETACH_REUSEPORT_BPF:
1335 		ret = reuseport_detach_prog(sk);
1336 		break;
1337 
1338 	case SO_DETACH_FILTER:
1339 		ret = sk_detach_filter(sk);
1340 		break;
1341 
1342 	case SO_LOCK_FILTER:
1343 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1344 			ret = -EPERM;
1345 		else
1346 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1347 		break;
1348 
1349 	case SO_PASSSEC:
1350 		if (valbool)
1351 			set_bit(SOCK_PASSSEC, &sock->flags);
1352 		else
1353 			clear_bit(SOCK_PASSSEC, &sock->flags);
1354 		break;
1355 	case SO_MARK:
1356 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1357 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1358 			ret = -EPERM;
1359 			break;
1360 		}
1361 
1362 		__sock_set_mark(sk, val);
1363 		break;
1364 	case SO_RCVMARK:
1365 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1366 		break;
1367 
1368 	case SO_RXQ_OVFL:
1369 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1370 		break;
1371 
1372 	case SO_WIFI_STATUS:
1373 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1374 		break;
1375 
1376 	case SO_PEEK_OFF:
1377 		if (sock->ops->set_peek_off)
1378 			ret = sock->ops->set_peek_off(sk, val);
1379 		else
1380 			ret = -EOPNOTSUPP;
1381 		break;
1382 
1383 	case SO_NOFCS:
1384 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1385 		break;
1386 
1387 	case SO_SELECT_ERR_QUEUE:
1388 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1389 		break;
1390 
1391 #ifdef CONFIG_NET_RX_BUSY_POLL
1392 	case SO_BUSY_POLL:
1393 		if (val < 0)
1394 			ret = -EINVAL;
1395 		else
1396 			WRITE_ONCE(sk->sk_ll_usec, val);
1397 		break;
1398 	case SO_PREFER_BUSY_POLL:
1399 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1400 			ret = -EPERM;
1401 		else
1402 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1403 		break;
1404 	case SO_BUSY_POLL_BUDGET:
1405 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1406 			ret = -EPERM;
1407 		} else {
1408 			if (val < 0 || val > U16_MAX)
1409 				ret = -EINVAL;
1410 			else
1411 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1412 		}
1413 		break;
1414 #endif
1415 
1416 	case SO_MAX_PACING_RATE:
1417 		{
1418 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1419 
1420 		if (sizeof(ulval) != sizeof(val) &&
1421 		    optlen >= sizeof(ulval) &&
1422 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1423 			ret = -EFAULT;
1424 			break;
1425 		}
1426 		if (ulval != ~0UL)
1427 			cmpxchg(&sk->sk_pacing_status,
1428 				SK_PACING_NONE,
1429 				SK_PACING_NEEDED);
1430 		sk->sk_max_pacing_rate = ulval;
1431 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1432 		break;
1433 		}
1434 	case SO_INCOMING_CPU:
1435 		reuseport_update_incoming_cpu(sk, val);
1436 		break;
1437 
1438 	case SO_CNX_ADVICE:
1439 		if (val == 1)
1440 			dst_negative_advice(sk);
1441 		break;
1442 
1443 	case SO_ZEROCOPY:
1444 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1445 			if (!(sk_is_tcp(sk) ||
1446 			      (sk->sk_type == SOCK_DGRAM &&
1447 			       sk->sk_protocol == IPPROTO_UDP)))
1448 				ret = -EOPNOTSUPP;
1449 		} else if (sk->sk_family != PF_RDS) {
1450 			ret = -EOPNOTSUPP;
1451 		}
1452 		if (!ret) {
1453 			if (val < 0 || val > 1)
1454 				ret = -EINVAL;
1455 			else
1456 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1457 		}
1458 		break;
1459 
1460 	case SO_TXTIME:
1461 		if (optlen != sizeof(struct sock_txtime)) {
1462 			ret = -EINVAL;
1463 			break;
1464 		} else if (copy_from_sockptr(&sk_txtime, optval,
1465 			   sizeof(struct sock_txtime))) {
1466 			ret = -EFAULT;
1467 			break;
1468 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1469 			ret = -EINVAL;
1470 			break;
1471 		}
1472 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1473 		 * scheduler has enough safe guards.
1474 		 */
1475 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1476 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1477 			ret = -EPERM;
1478 			break;
1479 		}
1480 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1481 		sk->sk_clockid = sk_txtime.clockid;
1482 		sk->sk_txtime_deadline_mode =
1483 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1484 		sk->sk_txtime_report_errors =
1485 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1486 		break;
1487 
1488 	case SO_BINDTOIFINDEX:
1489 		ret = sock_bindtoindex_locked(sk, val);
1490 		break;
1491 
1492 	case SO_BUF_LOCK:
1493 		if (val & ~SOCK_BUF_LOCK_MASK) {
1494 			ret = -EINVAL;
1495 			break;
1496 		}
1497 		sk->sk_userlocks = val | (sk->sk_userlocks &
1498 					  ~SOCK_BUF_LOCK_MASK);
1499 		break;
1500 
1501 	case SO_RESERVE_MEM:
1502 	{
1503 		int delta;
1504 
1505 		if (val < 0) {
1506 			ret = -EINVAL;
1507 			break;
1508 		}
1509 
1510 		delta = val - sk->sk_reserved_mem;
1511 		if (delta < 0)
1512 			sock_release_reserved_memory(sk, -delta);
1513 		else
1514 			ret = sock_reserve_memory(sk, delta);
1515 		break;
1516 	}
1517 
1518 	case SO_TXREHASH:
1519 		if (val < -1 || val > 1) {
1520 			ret = -EINVAL;
1521 			break;
1522 		}
1523 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1524 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1525 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1526 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1527 		break;
1528 
1529 	default:
1530 		ret = -ENOPROTOOPT;
1531 		break;
1532 	}
1533 	sockopt_release_sock(sk);
1534 	return ret;
1535 }
1536 
1537 int sock_setsockopt(struct socket *sock, int level, int optname,
1538 		    sockptr_t optval, unsigned int optlen)
1539 {
1540 	return sk_setsockopt(sock->sk, level, optname,
1541 			     optval, optlen);
1542 }
1543 EXPORT_SYMBOL(sock_setsockopt);
1544 
1545 static const struct cred *sk_get_peer_cred(struct sock *sk)
1546 {
1547 	const struct cred *cred;
1548 
1549 	spin_lock(&sk->sk_peer_lock);
1550 	cred = get_cred(sk->sk_peer_cred);
1551 	spin_unlock(&sk->sk_peer_lock);
1552 
1553 	return cred;
1554 }
1555 
1556 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1557 			  struct ucred *ucred)
1558 {
1559 	ucred->pid = pid_vnr(pid);
1560 	ucred->uid = ucred->gid = -1;
1561 	if (cred) {
1562 		struct user_namespace *current_ns = current_user_ns();
1563 
1564 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1565 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1566 	}
1567 }
1568 
1569 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1570 {
1571 	struct user_namespace *user_ns = current_user_ns();
1572 	int i;
1573 
1574 	for (i = 0; i < src->ngroups; i++) {
1575 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1576 
1577 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1578 			return -EFAULT;
1579 	}
1580 
1581 	return 0;
1582 }
1583 
1584 int sk_getsockopt(struct sock *sk, int level, int optname,
1585 		  sockptr_t optval, sockptr_t optlen)
1586 {
1587 	struct socket *sock = sk->sk_socket;
1588 
1589 	union {
1590 		int val;
1591 		u64 val64;
1592 		unsigned long ulval;
1593 		struct linger ling;
1594 		struct old_timeval32 tm32;
1595 		struct __kernel_old_timeval tm;
1596 		struct  __kernel_sock_timeval stm;
1597 		struct sock_txtime txtime;
1598 		struct so_timestamping timestamping;
1599 	} v;
1600 
1601 	int lv = sizeof(int);
1602 	int len;
1603 
1604 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1605 		return -EFAULT;
1606 	if (len < 0)
1607 		return -EINVAL;
1608 
1609 	memset(&v, 0, sizeof(v));
1610 
1611 	switch (optname) {
1612 	case SO_DEBUG:
1613 		v.val = sock_flag(sk, SOCK_DBG);
1614 		break;
1615 
1616 	case SO_DONTROUTE:
1617 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1618 		break;
1619 
1620 	case SO_BROADCAST:
1621 		v.val = sock_flag(sk, SOCK_BROADCAST);
1622 		break;
1623 
1624 	case SO_SNDBUF:
1625 		v.val = sk->sk_sndbuf;
1626 		break;
1627 
1628 	case SO_RCVBUF:
1629 		v.val = sk->sk_rcvbuf;
1630 		break;
1631 
1632 	case SO_REUSEADDR:
1633 		v.val = sk->sk_reuse;
1634 		break;
1635 
1636 	case SO_REUSEPORT:
1637 		v.val = sk->sk_reuseport;
1638 		break;
1639 
1640 	case SO_KEEPALIVE:
1641 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1642 		break;
1643 
1644 	case SO_TYPE:
1645 		v.val = sk->sk_type;
1646 		break;
1647 
1648 	case SO_PROTOCOL:
1649 		v.val = sk->sk_protocol;
1650 		break;
1651 
1652 	case SO_DOMAIN:
1653 		v.val = sk->sk_family;
1654 		break;
1655 
1656 	case SO_ERROR:
1657 		v.val = -sock_error(sk);
1658 		if (v.val == 0)
1659 			v.val = xchg(&sk->sk_err_soft, 0);
1660 		break;
1661 
1662 	case SO_OOBINLINE:
1663 		v.val = sock_flag(sk, SOCK_URGINLINE);
1664 		break;
1665 
1666 	case SO_NO_CHECK:
1667 		v.val = sk->sk_no_check_tx;
1668 		break;
1669 
1670 	case SO_PRIORITY:
1671 		v.val = sk->sk_priority;
1672 		break;
1673 
1674 	case SO_LINGER:
1675 		lv		= sizeof(v.ling);
1676 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1677 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1678 		break;
1679 
1680 	case SO_BSDCOMPAT:
1681 		break;
1682 
1683 	case SO_TIMESTAMP_OLD:
1684 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1685 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1686 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1687 		break;
1688 
1689 	case SO_TIMESTAMPNS_OLD:
1690 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1691 		break;
1692 
1693 	case SO_TIMESTAMP_NEW:
1694 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1695 		break;
1696 
1697 	case SO_TIMESTAMPNS_NEW:
1698 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1699 		break;
1700 
1701 	case SO_TIMESTAMPING_OLD:
1702 		lv = sizeof(v.timestamping);
1703 		v.timestamping.flags = sk->sk_tsflags;
1704 		v.timestamping.bind_phc = sk->sk_bind_phc;
1705 		break;
1706 
1707 	case SO_RCVTIMEO_OLD:
1708 	case SO_RCVTIMEO_NEW:
1709 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1710 		break;
1711 
1712 	case SO_SNDTIMEO_OLD:
1713 	case SO_SNDTIMEO_NEW:
1714 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1715 		break;
1716 
1717 	case SO_RCVLOWAT:
1718 		v.val = sk->sk_rcvlowat;
1719 		break;
1720 
1721 	case SO_SNDLOWAT:
1722 		v.val = 1;
1723 		break;
1724 
1725 	case SO_PASSCRED:
1726 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1727 		break;
1728 
1729 	case SO_PEERCRED:
1730 	{
1731 		struct ucred peercred;
1732 		if (len > sizeof(peercred))
1733 			len = sizeof(peercred);
1734 
1735 		spin_lock(&sk->sk_peer_lock);
1736 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1737 		spin_unlock(&sk->sk_peer_lock);
1738 
1739 		if (copy_to_sockptr(optval, &peercred, len))
1740 			return -EFAULT;
1741 		goto lenout;
1742 	}
1743 
1744 	case SO_PEERGROUPS:
1745 	{
1746 		const struct cred *cred;
1747 		int ret, n;
1748 
1749 		cred = sk_get_peer_cred(sk);
1750 		if (!cred)
1751 			return -ENODATA;
1752 
1753 		n = cred->group_info->ngroups;
1754 		if (len < n * sizeof(gid_t)) {
1755 			len = n * sizeof(gid_t);
1756 			put_cred(cred);
1757 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1758 		}
1759 		len = n * sizeof(gid_t);
1760 
1761 		ret = groups_to_user(optval, cred->group_info);
1762 		put_cred(cred);
1763 		if (ret)
1764 			return ret;
1765 		goto lenout;
1766 	}
1767 
1768 	case SO_PEERNAME:
1769 	{
1770 		char address[128];
1771 
1772 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1773 		if (lv < 0)
1774 			return -ENOTCONN;
1775 		if (lv < len)
1776 			return -EINVAL;
1777 		if (copy_to_sockptr(optval, address, len))
1778 			return -EFAULT;
1779 		goto lenout;
1780 	}
1781 
1782 	/* Dubious BSD thing... Probably nobody even uses it, but
1783 	 * the UNIX standard wants it for whatever reason... -DaveM
1784 	 */
1785 	case SO_ACCEPTCONN:
1786 		v.val = sk->sk_state == TCP_LISTEN;
1787 		break;
1788 
1789 	case SO_PASSSEC:
1790 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1791 		break;
1792 
1793 	case SO_PEERSEC:
1794 		return security_socket_getpeersec_stream(sock,
1795 							 optval, optlen, len);
1796 
1797 	case SO_MARK:
1798 		v.val = sk->sk_mark;
1799 		break;
1800 
1801 	case SO_RCVMARK:
1802 		v.val = sock_flag(sk, SOCK_RCVMARK);
1803 		break;
1804 
1805 	case SO_RXQ_OVFL:
1806 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1807 		break;
1808 
1809 	case SO_WIFI_STATUS:
1810 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1811 		break;
1812 
1813 	case SO_PEEK_OFF:
1814 		if (!sock->ops->set_peek_off)
1815 			return -EOPNOTSUPP;
1816 
1817 		v.val = sk->sk_peek_off;
1818 		break;
1819 	case SO_NOFCS:
1820 		v.val = sock_flag(sk, SOCK_NOFCS);
1821 		break;
1822 
1823 	case SO_BINDTODEVICE:
1824 		return sock_getbindtodevice(sk, optval, optlen, len);
1825 
1826 	case SO_GET_FILTER:
1827 		len = sk_get_filter(sk, optval, len);
1828 		if (len < 0)
1829 			return len;
1830 
1831 		goto lenout;
1832 
1833 	case SO_LOCK_FILTER:
1834 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1835 		break;
1836 
1837 	case SO_BPF_EXTENSIONS:
1838 		v.val = bpf_tell_extensions();
1839 		break;
1840 
1841 	case SO_SELECT_ERR_QUEUE:
1842 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1843 		break;
1844 
1845 #ifdef CONFIG_NET_RX_BUSY_POLL
1846 	case SO_BUSY_POLL:
1847 		v.val = sk->sk_ll_usec;
1848 		break;
1849 	case SO_PREFER_BUSY_POLL:
1850 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1851 		break;
1852 #endif
1853 
1854 	case SO_MAX_PACING_RATE:
1855 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1856 			lv = sizeof(v.ulval);
1857 			v.ulval = sk->sk_max_pacing_rate;
1858 		} else {
1859 			/* 32bit version */
1860 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1861 		}
1862 		break;
1863 
1864 	case SO_INCOMING_CPU:
1865 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1866 		break;
1867 
1868 	case SO_MEMINFO:
1869 	{
1870 		u32 meminfo[SK_MEMINFO_VARS];
1871 
1872 		sk_get_meminfo(sk, meminfo);
1873 
1874 		len = min_t(unsigned int, len, sizeof(meminfo));
1875 		if (copy_to_sockptr(optval, &meminfo, len))
1876 			return -EFAULT;
1877 
1878 		goto lenout;
1879 	}
1880 
1881 #ifdef CONFIG_NET_RX_BUSY_POLL
1882 	case SO_INCOMING_NAPI_ID:
1883 		v.val = READ_ONCE(sk->sk_napi_id);
1884 
1885 		/* aggregate non-NAPI IDs down to 0 */
1886 		if (v.val < MIN_NAPI_ID)
1887 			v.val = 0;
1888 
1889 		break;
1890 #endif
1891 
1892 	case SO_COOKIE:
1893 		lv = sizeof(u64);
1894 		if (len < lv)
1895 			return -EINVAL;
1896 		v.val64 = sock_gen_cookie(sk);
1897 		break;
1898 
1899 	case SO_ZEROCOPY:
1900 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1901 		break;
1902 
1903 	case SO_TXTIME:
1904 		lv = sizeof(v.txtime);
1905 		v.txtime.clockid = sk->sk_clockid;
1906 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1907 				  SOF_TXTIME_DEADLINE_MODE : 0;
1908 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1909 				  SOF_TXTIME_REPORT_ERRORS : 0;
1910 		break;
1911 
1912 	case SO_BINDTOIFINDEX:
1913 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1914 		break;
1915 
1916 	case SO_NETNS_COOKIE:
1917 		lv = sizeof(u64);
1918 		if (len != lv)
1919 			return -EINVAL;
1920 		v.val64 = sock_net(sk)->net_cookie;
1921 		break;
1922 
1923 	case SO_BUF_LOCK:
1924 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1925 		break;
1926 
1927 	case SO_RESERVE_MEM:
1928 		v.val = sk->sk_reserved_mem;
1929 		break;
1930 
1931 	case SO_TXREHASH:
1932 		v.val = sk->sk_txrehash;
1933 		break;
1934 
1935 	default:
1936 		/* We implement the SO_SNDLOWAT etc to not be settable
1937 		 * (1003.1g 7).
1938 		 */
1939 		return -ENOPROTOOPT;
1940 	}
1941 
1942 	if (len > lv)
1943 		len = lv;
1944 	if (copy_to_sockptr(optval, &v, len))
1945 		return -EFAULT;
1946 lenout:
1947 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1948 		return -EFAULT;
1949 	return 0;
1950 }
1951 
1952 int sock_getsockopt(struct socket *sock, int level, int optname,
1953 		    char __user *optval, int __user *optlen)
1954 {
1955 	return sk_getsockopt(sock->sk, level, optname,
1956 			     USER_SOCKPTR(optval),
1957 			     USER_SOCKPTR(optlen));
1958 }
1959 
1960 /*
1961  * Initialize an sk_lock.
1962  *
1963  * (We also register the sk_lock with the lock validator.)
1964  */
1965 static inline void sock_lock_init(struct sock *sk)
1966 {
1967 	if (sk->sk_kern_sock)
1968 		sock_lock_init_class_and_name(
1969 			sk,
1970 			af_family_kern_slock_key_strings[sk->sk_family],
1971 			af_family_kern_slock_keys + sk->sk_family,
1972 			af_family_kern_key_strings[sk->sk_family],
1973 			af_family_kern_keys + sk->sk_family);
1974 	else
1975 		sock_lock_init_class_and_name(
1976 			sk,
1977 			af_family_slock_key_strings[sk->sk_family],
1978 			af_family_slock_keys + sk->sk_family,
1979 			af_family_key_strings[sk->sk_family],
1980 			af_family_keys + sk->sk_family);
1981 }
1982 
1983 /*
1984  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1985  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1986  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1987  */
1988 static void sock_copy(struct sock *nsk, const struct sock *osk)
1989 {
1990 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1991 #ifdef CONFIG_SECURITY_NETWORK
1992 	void *sptr = nsk->sk_security;
1993 #endif
1994 
1995 	/* If we move sk_tx_queue_mapping out of the private section,
1996 	 * we must check if sk_tx_queue_clear() is called after
1997 	 * sock_copy() in sk_clone_lock().
1998 	 */
1999 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2000 		     offsetof(struct sock, sk_dontcopy_begin) ||
2001 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2002 		     offsetof(struct sock, sk_dontcopy_end));
2003 
2004 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2005 
2006 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2007 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2008 
2009 #ifdef CONFIG_SECURITY_NETWORK
2010 	nsk->sk_security = sptr;
2011 	security_sk_clone(osk, nsk);
2012 #endif
2013 }
2014 
2015 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2016 		int family)
2017 {
2018 	struct sock *sk;
2019 	struct kmem_cache *slab;
2020 
2021 	slab = prot->slab;
2022 	if (slab != NULL) {
2023 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2024 		if (!sk)
2025 			return sk;
2026 		if (want_init_on_alloc(priority))
2027 			sk_prot_clear_nulls(sk, prot->obj_size);
2028 	} else
2029 		sk = kmalloc(prot->obj_size, priority);
2030 
2031 	if (sk != NULL) {
2032 		if (security_sk_alloc(sk, family, priority))
2033 			goto out_free;
2034 
2035 		if (!try_module_get(prot->owner))
2036 			goto out_free_sec;
2037 	}
2038 
2039 	return sk;
2040 
2041 out_free_sec:
2042 	security_sk_free(sk);
2043 out_free:
2044 	if (slab != NULL)
2045 		kmem_cache_free(slab, sk);
2046 	else
2047 		kfree(sk);
2048 	return NULL;
2049 }
2050 
2051 static void sk_prot_free(struct proto *prot, struct sock *sk)
2052 {
2053 	struct kmem_cache *slab;
2054 	struct module *owner;
2055 
2056 	owner = prot->owner;
2057 	slab = prot->slab;
2058 
2059 	cgroup_sk_free(&sk->sk_cgrp_data);
2060 	mem_cgroup_sk_free(sk);
2061 	security_sk_free(sk);
2062 	if (slab != NULL)
2063 		kmem_cache_free(slab, sk);
2064 	else
2065 		kfree(sk);
2066 	module_put(owner);
2067 }
2068 
2069 /**
2070  *	sk_alloc - All socket objects are allocated here
2071  *	@net: the applicable net namespace
2072  *	@family: protocol family
2073  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2074  *	@prot: struct proto associated with this new sock instance
2075  *	@kern: is this to be a kernel socket?
2076  */
2077 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2078 		      struct proto *prot, int kern)
2079 {
2080 	struct sock *sk;
2081 
2082 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2083 	if (sk) {
2084 		sk->sk_family = family;
2085 		/*
2086 		 * See comment in struct sock definition to understand
2087 		 * why we need sk_prot_creator -acme
2088 		 */
2089 		sk->sk_prot = sk->sk_prot_creator = prot;
2090 		sk->sk_kern_sock = kern;
2091 		sock_lock_init(sk);
2092 		sk->sk_net_refcnt = kern ? 0 : 1;
2093 		if (likely(sk->sk_net_refcnt)) {
2094 			get_net_track(net, &sk->ns_tracker, priority);
2095 			sock_inuse_add(net, 1);
2096 		} else {
2097 			__netns_tracker_alloc(net, &sk->ns_tracker,
2098 					      false, priority);
2099 		}
2100 
2101 		sock_net_set(sk, net);
2102 		refcount_set(&sk->sk_wmem_alloc, 1);
2103 
2104 		mem_cgroup_sk_alloc(sk);
2105 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2106 		sock_update_classid(&sk->sk_cgrp_data);
2107 		sock_update_netprioidx(&sk->sk_cgrp_data);
2108 		sk_tx_queue_clear(sk);
2109 	}
2110 
2111 	return sk;
2112 }
2113 EXPORT_SYMBOL(sk_alloc);
2114 
2115 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2116  * grace period. This is the case for UDP sockets and TCP listeners.
2117  */
2118 static void __sk_destruct(struct rcu_head *head)
2119 {
2120 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2121 	struct sk_filter *filter;
2122 
2123 	if (sk->sk_destruct)
2124 		sk->sk_destruct(sk);
2125 
2126 	filter = rcu_dereference_check(sk->sk_filter,
2127 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2128 	if (filter) {
2129 		sk_filter_uncharge(sk, filter);
2130 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2131 	}
2132 
2133 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2134 
2135 #ifdef CONFIG_BPF_SYSCALL
2136 	bpf_sk_storage_free(sk);
2137 #endif
2138 
2139 	if (atomic_read(&sk->sk_omem_alloc))
2140 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2141 			 __func__, atomic_read(&sk->sk_omem_alloc));
2142 
2143 	if (sk->sk_frag.page) {
2144 		put_page(sk->sk_frag.page);
2145 		sk->sk_frag.page = NULL;
2146 	}
2147 
2148 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2149 	put_cred(sk->sk_peer_cred);
2150 	put_pid(sk->sk_peer_pid);
2151 
2152 	if (likely(sk->sk_net_refcnt))
2153 		put_net_track(sock_net(sk), &sk->ns_tracker);
2154 	else
2155 		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2156 
2157 	sk_prot_free(sk->sk_prot_creator, sk);
2158 }
2159 
2160 void sk_destruct(struct sock *sk)
2161 {
2162 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2163 
2164 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2165 		reuseport_detach_sock(sk);
2166 		use_call_rcu = true;
2167 	}
2168 
2169 	if (use_call_rcu)
2170 		call_rcu(&sk->sk_rcu, __sk_destruct);
2171 	else
2172 		__sk_destruct(&sk->sk_rcu);
2173 }
2174 
2175 static void __sk_free(struct sock *sk)
2176 {
2177 	if (likely(sk->sk_net_refcnt))
2178 		sock_inuse_add(sock_net(sk), -1);
2179 
2180 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2181 		sock_diag_broadcast_destroy(sk);
2182 	else
2183 		sk_destruct(sk);
2184 }
2185 
2186 void sk_free(struct sock *sk)
2187 {
2188 	/*
2189 	 * We subtract one from sk_wmem_alloc and can know if
2190 	 * some packets are still in some tx queue.
2191 	 * If not null, sock_wfree() will call __sk_free(sk) later
2192 	 */
2193 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2194 		__sk_free(sk);
2195 }
2196 EXPORT_SYMBOL(sk_free);
2197 
2198 static void sk_init_common(struct sock *sk)
2199 {
2200 	skb_queue_head_init(&sk->sk_receive_queue);
2201 	skb_queue_head_init(&sk->sk_write_queue);
2202 	skb_queue_head_init(&sk->sk_error_queue);
2203 
2204 	rwlock_init(&sk->sk_callback_lock);
2205 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2206 			af_rlock_keys + sk->sk_family,
2207 			af_family_rlock_key_strings[sk->sk_family]);
2208 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2209 			af_wlock_keys + sk->sk_family,
2210 			af_family_wlock_key_strings[sk->sk_family]);
2211 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2212 			af_elock_keys + sk->sk_family,
2213 			af_family_elock_key_strings[sk->sk_family]);
2214 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2215 			af_callback_keys + sk->sk_family,
2216 			af_family_clock_key_strings[sk->sk_family]);
2217 }
2218 
2219 /**
2220  *	sk_clone_lock - clone a socket, and lock its clone
2221  *	@sk: the socket to clone
2222  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2223  *
2224  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2225  */
2226 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2227 {
2228 	struct proto *prot = READ_ONCE(sk->sk_prot);
2229 	struct sk_filter *filter;
2230 	bool is_charged = true;
2231 	struct sock *newsk;
2232 
2233 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2234 	if (!newsk)
2235 		goto out;
2236 
2237 	sock_copy(newsk, sk);
2238 
2239 	newsk->sk_prot_creator = prot;
2240 
2241 	/* SANITY */
2242 	if (likely(newsk->sk_net_refcnt)) {
2243 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2244 		sock_inuse_add(sock_net(newsk), 1);
2245 	} else {
2246 		/* Kernel sockets are not elevating the struct net refcount.
2247 		 * Instead, use a tracker to more easily detect if a layer
2248 		 * is not properly dismantling its kernel sockets at netns
2249 		 * destroy time.
2250 		 */
2251 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2252 				      false, priority);
2253 	}
2254 	sk_node_init(&newsk->sk_node);
2255 	sock_lock_init(newsk);
2256 	bh_lock_sock(newsk);
2257 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2258 	newsk->sk_backlog.len = 0;
2259 
2260 	atomic_set(&newsk->sk_rmem_alloc, 0);
2261 
2262 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2263 	refcount_set(&newsk->sk_wmem_alloc, 1);
2264 
2265 	atomic_set(&newsk->sk_omem_alloc, 0);
2266 	sk_init_common(newsk);
2267 
2268 	newsk->sk_dst_cache	= NULL;
2269 	newsk->sk_dst_pending_confirm = 0;
2270 	newsk->sk_wmem_queued	= 0;
2271 	newsk->sk_forward_alloc = 0;
2272 	newsk->sk_reserved_mem  = 0;
2273 	atomic_set(&newsk->sk_drops, 0);
2274 	newsk->sk_send_head	= NULL;
2275 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2276 	atomic_set(&newsk->sk_zckey, 0);
2277 
2278 	sock_reset_flag(newsk, SOCK_DONE);
2279 
2280 	/* sk->sk_memcg will be populated at accept() time */
2281 	newsk->sk_memcg = NULL;
2282 
2283 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2284 
2285 	rcu_read_lock();
2286 	filter = rcu_dereference(sk->sk_filter);
2287 	if (filter != NULL)
2288 		/* though it's an empty new sock, the charging may fail
2289 		 * if sysctl_optmem_max was changed between creation of
2290 		 * original socket and cloning
2291 		 */
2292 		is_charged = sk_filter_charge(newsk, filter);
2293 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2294 	rcu_read_unlock();
2295 
2296 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2297 		/* We need to make sure that we don't uncharge the new
2298 		 * socket if we couldn't charge it in the first place
2299 		 * as otherwise we uncharge the parent's filter.
2300 		 */
2301 		if (!is_charged)
2302 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2303 		sk_free_unlock_clone(newsk);
2304 		newsk = NULL;
2305 		goto out;
2306 	}
2307 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2308 
2309 	if (bpf_sk_storage_clone(sk, newsk)) {
2310 		sk_free_unlock_clone(newsk);
2311 		newsk = NULL;
2312 		goto out;
2313 	}
2314 
2315 	/* Clear sk_user_data if parent had the pointer tagged
2316 	 * as not suitable for copying when cloning.
2317 	 */
2318 	if (sk_user_data_is_nocopy(newsk))
2319 		newsk->sk_user_data = NULL;
2320 
2321 	newsk->sk_err	   = 0;
2322 	newsk->sk_err_soft = 0;
2323 	newsk->sk_priority = 0;
2324 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2325 
2326 	/* Before updating sk_refcnt, we must commit prior changes to memory
2327 	 * (Documentation/RCU/rculist_nulls.rst for details)
2328 	 */
2329 	smp_wmb();
2330 	refcount_set(&newsk->sk_refcnt, 2);
2331 
2332 	sk_set_socket(newsk, NULL);
2333 	sk_tx_queue_clear(newsk);
2334 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2335 
2336 	if (newsk->sk_prot->sockets_allocated)
2337 		sk_sockets_allocated_inc(newsk);
2338 
2339 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2340 		net_enable_timestamp();
2341 out:
2342 	return newsk;
2343 }
2344 EXPORT_SYMBOL_GPL(sk_clone_lock);
2345 
2346 void sk_free_unlock_clone(struct sock *sk)
2347 {
2348 	/* It is still raw copy of parent, so invalidate
2349 	 * destructor and make plain sk_free() */
2350 	sk->sk_destruct = NULL;
2351 	bh_unlock_sock(sk);
2352 	sk_free(sk);
2353 }
2354 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2355 
2356 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2357 {
2358 	bool is_ipv6 = false;
2359 	u32 max_size;
2360 
2361 #if IS_ENABLED(CONFIG_IPV6)
2362 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2363 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2364 #endif
2365 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2366 	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2367 			READ_ONCE(dst->dev->gso_ipv4_max_size);
2368 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2369 		max_size = GSO_LEGACY_MAX_SIZE;
2370 
2371 	return max_size - (MAX_TCP_HEADER + 1);
2372 }
2373 
2374 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2375 {
2376 	u32 max_segs = 1;
2377 
2378 	sk->sk_route_caps = dst->dev->features;
2379 	if (sk_is_tcp(sk))
2380 		sk->sk_route_caps |= NETIF_F_GSO;
2381 	if (sk->sk_route_caps & NETIF_F_GSO)
2382 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2383 	if (unlikely(sk->sk_gso_disabled))
2384 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2385 	if (sk_can_gso(sk)) {
2386 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2387 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2388 		} else {
2389 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2390 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2391 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2392 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2393 		}
2394 	}
2395 	sk->sk_gso_max_segs = max_segs;
2396 	sk_dst_set(sk, dst);
2397 }
2398 EXPORT_SYMBOL_GPL(sk_setup_caps);
2399 
2400 /*
2401  *	Simple resource managers for sockets.
2402  */
2403 
2404 
2405 /*
2406  * Write buffer destructor automatically called from kfree_skb.
2407  */
2408 void sock_wfree(struct sk_buff *skb)
2409 {
2410 	struct sock *sk = skb->sk;
2411 	unsigned int len = skb->truesize;
2412 	bool free;
2413 
2414 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2415 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2416 		    sk->sk_write_space == sock_def_write_space) {
2417 			rcu_read_lock();
2418 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2419 			sock_def_write_space_wfree(sk);
2420 			rcu_read_unlock();
2421 			if (unlikely(free))
2422 				__sk_free(sk);
2423 			return;
2424 		}
2425 
2426 		/*
2427 		 * Keep a reference on sk_wmem_alloc, this will be released
2428 		 * after sk_write_space() call
2429 		 */
2430 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2431 		sk->sk_write_space(sk);
2432 		len = 1;
2433 	}
2434 	/*
2435 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2436 	 * could not do because of in-flight packets
2437 	 */
2438 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2439 		__sk_free(sk);
2440 }
2441 EXPORT_SYMBOL(sock_wfree);
2442 
2443 /* This variant of sock_wfree() is used by TCP,
2444  * since it sets SOCK_USE_WRITE_QUEUE.
2445  */
2446 void __sock_wfree(struct sk_buff *skb)
2447 {
2448 	struct sock *sk = skb->sk;
2449 
2450 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2451 		__sk_free(sk);
2452 }
2453 
2454 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2455 {
2456 	skb_orphan(skb);
2457 	skb->sk = sk;
2458 #ifdef CONFIG_INET
2459 	if (unlikely(!sk_fullsock(sk))) {
2460 		skb->destructor = sock_edemux;
2461 		sock_hold(sk);
2462 		return;
2463 	}
2464 #endif
2465 	skb->destructor = sock_wfree;
2466 	skb_set_hash_from_sk(skb, sk);
2467 	/*
2468 	 * We used to take a refcount on sk, but following operation
2469 	 * is enough to guarantee sk_free() wont free this sock until
2470 	 * all in-flight packets are completed
2471 	 */
2472 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2473 }
2474 EXPORT_SYMBOL(skb_set_owner_w);
2475 
2476 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2477 {
2478 #ifdef CONFIG_TLS_DEVICE
2479 	/* Drivers depend on in-order delivery for crypto offload,
2480 	 * partial orphan breaks out-of-order-OK logic.
2481 	 */
2482 	if (skb->decrypted)
2483 		return false;
2484 #endif
2485 	return (skb->destructor == sock_wfree ||
2486 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2487 }
2488 
2489 /* This helper is used by netem, as it can hold packets in its
2490  * delay queue. We want to allow the owner socket to send more
2491  * packets, as if they were already TX completed by a typical driver.
2492  * But we also want to keep skb->sk set because some packet schedulers
2493  * rely on it (sch_fq for example).
2494  */
2495 void skb_orphan_partial(struct sk_buff *skb)
2496 {
2497 	if (skb_is_tcp_pure_ack(skb))
2498 		return;
2499 
2500 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2501 		return;
2502 
2503 	skb_orphan(skb);
2504 }
2505 EXPORT_SYMBOL(skb_orphan_partial);
2506 
2507 /*
2508  * Read buffer destructor automatically called from kfree_skb.
2509  */
2510 void sock_rfree(struct sk_buff *skb)
2511 {
2512 	struct sock *sk = skb->sk;
2513 	unsigned int len = skb->truesize;
2514 
2515 	atomic_sub(len, &sk->sk_rmem_alloc);
2516 	sk_mem_uncharge(sk, len);
2517 }
2518 EXPORT_SYMBOL(sock_rfree);
2519 
2520 /*
2521  * Buffer destructor for skbs that are not used directly in read or write
2522  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2523  */
2524 void sock_efree(struct sk_buff *skb)
2525 {
2526 	sock_put(skb->sk);
2527 }
2528 EXPORT_SYMBOL(sock_efree);
2529 
2530 /* Buffer destructor for prefetch/receive path where reference count may
2531  * not be held, e.g. for listen sockets.
2532  */
2533 #ifdef CONFIG_INET
2534 void sock_pfree(struct sk_buff *skb)
2535 {
2536 	if (sk_is_refcounted(skb->sk))
2537 		sock_gen_put(skb->sk);
2538 }
2539 EXPORT_SYMBOL(sock_pfree);
2540 #endif /* CONFIG_INET */
2541 
2542 kuid_t sock_i_uid(struct sock *sk)
2543 {
2544 	kuid_t uid;
2545 
2546 	read_lock_bh(&sk->sk_callback_lock);
2547 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2548 	read_unlock_bh(&sk->sk_callback_lock);
2549 	return uid;
2550 }
2551 EXPORT_SYMBOL(sock_i_uid);
2552 
2553 unsigned long sock_i_ino(struct sock *sk)
2554 {
2555 	unsigned long ino;
2556 
2557 	read_lock_bh(&sk->sk_callback_lock);
2558 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2559 	read_unlock_bh(&sk->sk_callback_lock);
2560 	return ino;
2561 }
2562 EXPORT_SYMBOL(sock_i_ino);
2563 
2564 /*
2565  * Allocate a skb from the socket's send buffer.
2566  */
2567 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2568 			     gfp_t priority)
2569 {
2570 	if (force ||
2571 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2572 		struct sk_buff *skb = alloc_skb(size, priority);
2573 
2574 		if (skb) {
2575 			skb_set_owner_w(skb, sk);
2576 			return skb;
2577 		}
2578 	}
2579 	return NULL;
2580 }
2581 EXPORT_SYMBOL(sock_wmalloc);
2582 
2583 static void sock_ofree(struct sk_buff *skb)
2584 {
2585 	struct sock *sk = skb->sk;
2586 
2587 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2588 }
2589 
2590 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2591 			     gfp_t priority)
2592 {
2593 	struct sk_buff *skb;
2594 
2595 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2596 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2597 	    READ_ONCE(sysctl_optmem_max))
2598 		return NULL;
2599 
2600 	skb = alloc_skb(size, priority);
2601 	if (!skb)
2602 		return NULL;
2603 
2604 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2605 	skb->sk = sk;
2606 	skb->destructor = sock_ofree;
2607 	return skb;
2608 }
2609 
2610 /*
2611  * Allocate a memory block from the socket's option memory buffer.
2612  */
2613 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2614 {
2615 	int optmem_max = READ_ONCE(sysctl_optmem_max);
2616 
2617 	if ((unsigned int)size <= optmem_max &&
2618 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2619 		void *mem;
2620 		/* First do the add, to avoid the race if kmalloc
2621 		 * might sleep.
2622 		 */
2623 		atomic_add(size, &sk->sk_omem_alloc);
2624 		mem = kmalloc(size, priority);
2625 		if (mem)
2626 			return mem;
2627 		atomic_sub(size, &sk->sk_omem_alloc);
2628 	}
2629 	return NULL;
2630 }
2631 EXPORT_SYMBOL(sock_kmalloc);
2632 
2633 /* Free an option memory block. Note, we actually want the inline
2634  * here as this allows gcc to detect the nullify and fold away the
2635  * condition entirely.
2636  */
2637 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2638 				  const bool nullify)
2639 {
2640 	if (WARN_ON_ONCE(!mem))
2641 		return;
2642 	if (nullify)
2643 		kfree_sensitive(mem);
2644 	else
2645 		kfree(mem);
2646 	atomic_sub(size, &sk->sk_omem_alloc);
2647 }
2648 
2649 void sock_kfree_s(struct sock *sk, void *mem, int size)
2650 {
2651 	__sock_kfree_s(sk, mem, size, false);
2652 }
2653 EXPORT_SYMBOL(sock_kfree_s);
2654 
2655 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2656 {
2657 	__sock_kfree_s(sk, mem, size, true);
2658 }
2659 EXPORT_SYMBOL(sock_kzfree_s);
2660 
2661 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2662    I think, these locks should be removed for datagram sockets.
2663  */
2664 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2665 {
2666 	DEFINE_WAIT(wait);
2667 
2668 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2669 	for (;;) {
2670 		if (!timeo)
2671 			break;
2672 		if (signal_pending(current))
2673 			break;
2674 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2675 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2676 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2677 			break;
2678 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2679 			break;
2680 		if (sk->sk_err)
2681 			break;
2682 		timeo = schedule_timeout(timeo);
2683 	}
2684 	finish_wait(sk_sleep(sk), &wait);
2685 	return timeo;
2686 }
2687 
2688 
2689 /*
2690  *	Generic send/receive buffer handlers
2691  */
2692 
2693 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2694 				     unsigned long data_len, int noblock,
2695 				     int *errcode, int max_page_order)
2696 {
2697 	struct sk_buff *skb;
2698 	long timeo;
2699 	int err;
2700 
2701 	timeo = sock_sndtimeo(sk, noblock);
2702 	for (;;) {
2703 		err = sock_error(sk);
2704 		if (err != 0)
2705 			goto failure;
2706 
2707 		err = -EPIPE;
2708 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2709 			goto failure;
2710 
2711 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2712 			break;
2713 
2714 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2715 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2716 		err = -EAGAIN;
2717 		if (!timeo)
2718 			goto failure;
2719 		if (signal_pending(current))
2720 			goto interrupted;
2721 		timeo = sock_wait_for_wmem(sk, timeo);
2722 	}
2723 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2724 				   errcode, sk->sk_allocation);
2725 	if (skb)
2726 		skb_set_owner_w(skb, sk);
2727 	return skb;
2728 
2729 interrupted:
2730 	err = sock_intr_errno(timeo);
2731 failure:
2732 	*errcode = err;
2733 	return NULL;
2734 }
2735 EXPORT_SYMBOL(sock_alloc_send_pskb);
2736 
2737 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2738 		     struct sockcm_cookie *sockc)
2739 {
2740 	u32 tsflags;
2741 
2742 	switch (cmsg->cmsg_type) {
2743 	case SO_MARK:
2744 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2745 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2746 			return -EPERM;
2747 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2748 			return -EINVAL;
2749 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2750 		break;
2751 	case SO_TIMESTAMPING_OLD:
2752 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2753 			return -EINVAL;
2754 
2755 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2756 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2757 			return -EINVAL;
2758 
2759 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2760 		sockc->tsflags |= tsflags;
2761 		break;
2762 	case SCM_TXTIME:
2763 		if (!sock_flag(sk, SOCK_TXTIME))
2764 			return -EINVAL;
2765 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2766 			return -EINVAL;
2767 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2768 		break;
2769 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2770 	case SCM_RIGHTS:
2771 	case SCM_CREDENTIALS:
2772 		break;
2773 	default:
2774 		return -EINVAL;
2775 	}
2776 	return 0;
2777 }
2778 EXPORT_SYMBOL(__sock_cmsg_send);
2779 
2780 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2781 		   struct sockcm_cookie *sockc)
2782 {
2783 	struct cmsghdr *cmsg;
2784 	int ret;
2785 
2786 	for_each_cmsghdr(cmsg, msg) {
2787 		if (!CMSG_OK(msg, cmsg))
2788 			return -EINVAL;
2789 		if (cmsg->cmsg_level != SOL_SOCKET)
2790 			continue;
2791 		ret = __sock_cmsg_send(sk, cmsg, sockc);
2792 		if (ret)
2793 			return ret;
2794 	}
2795 	return 0;
2796 }
2797 EXPORT_SYMBOL(sock_cmsg_send);
2798 
2799 static void sk_enter_memory_pressure(struct sock *sk)
2800 {
2801 	if (!sk->sk_prot->enter_memory_pressure)
2802 		return;
2803 
2804 	sk->sk_prot->enter_memory_pressure(sk);
2805 }
2806 
2807 static void sk_leave_memory_pressure(struct sock *sk)
2808 {
2809 	if (sk->sk_prot->leave_memory_pressure) {
2810 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2811 				     tcp_leave_memory_pressure, sk);
2812 	} else {
2813 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2814 
2815 		if (memory_pressure && READ_ONCE(*memory_pressure))
2816 			WRITE_ONCE(*memory_pressure, 0);
2817 	}
2818 }
2819 
2820 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2821 
2822 /**
2823  * skb_page_frag_refill - check that a page_frag contains enough room
2824  * @sz: minimum size of the fragment we want to get
2825  * @pfrag: pointer to page_frag
2826  * @gfp: priority for memory allocation
2827  *
2828  * Note: While this allocator tries to use high order pages, there is
2829  * no guarantee that allocations succeed. Therefore, @sz MUST be
2830  * less or equal than PAGE_SIZE.
2831  */
2832 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2833 {
2834 	if (pfrag->page) {
2835 		if (page_ref_count(pfrag->page) == 1) {
2836 			pfrag->offset = 0;
2837 			return true;
2838 		}
2839 		if (pfrag->offset + sz <= pfrag->size)
2840 			return true;
2841 		put_page(pfrag->page);
2842 	}
2843 
2844 	pfrag->offset = 0;
2845 	if (SKB_FRAG_PAGE_ORDER &&
2846 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2847 		/* Avoid direct reclaim but allow kswapd to wake */
2848 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2849 					  __GFP_COMP | __GFP_NOWARN |
2850 					  __GFP_NORETRY,
2851 					  SKB_FRAG_PAGE_ORDER);
2852 		if (likely(pfrag->page)) {
2853 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2854 			return true;
2855 		}
2856 	}
2857 	pfrag->page = alloc_page(gfp);
2858 	if (likely(pfrag->page)) {
2859 		pfrag->size = PAGE_SIZE;
2860 		return true;
2861 	}
2862 	return false;
2863 }
2864 EXPORT_SYMBOL(skb_page_frag_refill);
2865 
2866 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2867 {
2868 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2869 		return true;
2870 
2871 	sk_enter_memory_pressure(sk);
2872 	sk_stream_moderate_sndbuf(sk);
2873 	return false;
2874 }
2875 EXPORT_SYMBOL(sk_page_frag_refill);
2876 
2877 void __lock_sock(struct sock *sk)
2878 	__releases(&sk->sk_lock.slock)
2879 	__acquires(&sk->sk_lock.slock)
2880 {
2881 	DEFINE_WAIT(wait);
2882 
2883 	for (;;) {
2884 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2885 					TASK_UNINTERRUPTIBLE);
2886 		spin_unlock_bh(&sk->sk_lock.slock);
2887 		schedule();
2888 		spin_lock_bh(&sk->sk_lock.slock);
2889 		if (!sock_owned_by_user(sk))
2890 			break;
2891 	}
2892 	finish_wait(&sk->sk_lock.wq, &wait);
2893 }
2894 
2895 void __release_sock(struct sock *sk)
2896 	__releases(&sk->sk_lock.slock)
2897 	__acquires(&sk->sk_lock.slock)
2898 {
2899 	struct sk_buff *skb, *next;
2900 
2901 	while ((skb = sk->sk_backlog.head) != NULL) {
2902 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2903 
2904 		spin_unlock_bh(&sk->sk_lock.slock);
2905 
2906 		do {
2907 			next = skb->next;
2908 			prefetch(next);
2909 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2910 			skb_mark_not_on_list(skb);
2911 			sk_backlog_rcv(sk, skb);
2912 
2913 			cond_resched();
2914 
2915 			skb = next;
2916 		} while (skb != NULL);
2917 
2918 		spin_lock_bh(&sk->sk_lock.slock);
2919 	}
2920 
2921 	/*
2922 	 * Doing the zeroing here guarantee we can not loop forever
2923 	 * while a wild producer attempts to flood us.
2924 	 */
2925 	sk->sk_backlog.len = 0;
2926 }
2927 
2928 void __sk_flush_backlog(struct sock *sk)
2929 {
2930 	spin_lock_bh(&sk->sk_lock.slock);
2931 	__release_sock(sk);
2932 	spin_unlock_bh(&sk->sk_lock.slock);
2933 }
2934 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2935 
2936 /**
2937  * sk_wait_data - wait for data to arrive at sk_receive_queue
2938  * @sk:    sock to wait on
2939  * @timeo: for how long
2940  * @skb:   last skb seen on sk_receive_queue
2941  *
2942  * Now socket state including sk->sk_err is changed only under lock,
2943  * hence we may omit checks after joining wait queue.
2944  * We check receive queue before schedule() only as optimization;
2945  * it is very likely that release_sock() added new data.
2946  */
2947 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2948 {
2949 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2950 	int rc;
2951 
2952 	add_wait_queue(sk_sleep(sk), &wait);
2953 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2954 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2955 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2956 	remove_wait_queue(sk_sleep(sk), &wait);
2957 	return rc;
2958 }
2959 EXPORT_SYMBOL(sk_wait_data);
2960 
2961 /**
2962  *	__sk_mem_raise_allocated - increase memory_allocated
2963  *	@sk: socket
2964  *	@size: memory size to allocate
2965  *	@amt: pages to allocate
2966  *	@kind: allocation type
2967  *
2968  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2969  */
2970 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2971 {
2972 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2973 	struct proto *prot = sk->sk_prot;
2974 	bool charged = true;
2975 	long allocated;
2976 
2977 	sk_memory_allocated_add(sk, amt);
2978 	allocated = sk_memory_allocated(sk);
2979 	if (memcg_charge &&
2980 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2981 						gfp_memcg_charge())))
2982 		goto suppress_allocation;
2983 
2984 	/* Under limit. */
2985 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2986 		sk_leave_memory_pressure(sk);
2987 		return 1;
2988 	}
2989 
2990 	/* Under pressure. */
2991 	if (allocated > sk_prot_mem_limits(sk, 1))
2992 		sk_enter_memory_pressure(sk);
2993 
2994 	/* Over hard limit. */
2995 	if (allocated > sk_prot_mem_limits(sk, 2))
2996 		goto suppress_allocation;
2997 
2998 	/* guarantee minimum buffer size under pressure */
2999 	if (kind == SK_MEM_RECV) {
3000 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3001 			return 1;
3002 
3003 	} else { /* SK_MEM_SEND */
3004 		int wmem0 = sk_get_wmem0(sk, prot);
3005 
3006 		if (sk->sk_type == SOCK_STREAM) {
3007 			if (sk->sk_wmem_queued < wmem0)
3008 				return 1;
3009 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3010 				return 1;
3011 		}
3012 	}
3013 
3014 	if (sk_has_memory_pressure(sk)) {
3015 		u64 alloc;
3016 
3017 		if (!sk_under_memory_pressure(sk))
3018 			return 1;
3019 		alloc = sk_sockets_allocated_read_positive(sk);
3020 		if (sk_prot_mem_limits(sk, 2) > alloc *
3021 		    sk_mem_pages(sk->sk_wmem_queued +
3022 				 atomic_read(&sk->sk_rmem_alloc) +
3023 				 sk->sk_forward_alloc))
3024 			return 1;
3025 	}
3026 
3027 suppress_allocation:
3028 
3029 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3030 		sk_stream_moderate_sndbuf(sk);
3031 
3032 		/* Fail only if socket is _under_ its sndbuf.
3033 		 * In this case we cannot block, so that we have to fail.
3034 		 */
3035 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3036 			/* Force charge with __GFP_NOFAIL */
3037 			if (memcg_charge && !charged) {
3038 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3039 					gfp_memcg_charge() | __GFP_NOFAIL);
3040 			}
3041 			return 1;
3042 		}
3043 	}
3044 
3045 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3046 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3047 
3048 	sk_memory_allocated_sub(sk, amt);
3049 
3050 	if (memcg_charge && charged)
3051 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3052 
3053 	return 0;
3054 }
3055 
3056 /**
3057  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3058  *	@sk: socket
3059  *	@size: memory size to allocate
3060  *	@kind: allocation type
3061  *
3062  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3063  *	rmem allocation. This function assumes that protocols which have
3064  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3065  */
3066 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3067 {
3068 	int ret, amt = sk_mem_pages(size);
3069 
3070 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3071 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3072 	if (!ret)
3073 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3074 	return ret;
3075 }
3076 EXPORT_SYMBOL(__sk_mem_schedule);
3077 
3078 /**
3079  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3080  *	@sk: socket
3081  *	@amount: number of quanta
3082  *
3083  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3084  */
3085 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3086 {
3087 	sk_memory_allocated_sub(sk, amount);
3088 
3089 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3090 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3091 
3092 	if (sk_under_memory_pressure(sk) &&
3093 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3094 		sk_leave_memory_pressure(sk);
3095 }
3096 
3097 /**
3098  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3099  *	@sk: socket
3100  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3101  */
3102 void __sk_mem_reclaim(struct sock *sk, int amount)
3103 {
3104 	amount >>= PAGE_SHIFT;
3105 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3106 	__sk_mem_reduce_allocated(sk, amount);
3107 }
3108 EXPORT_SYMBOL(__sk_mem_reclaim);
3109 
3110 int sk_set_peek_off(struct sock *sk, int val)
3111 {
3112 	sk->sk_peek_off = val;
3113 	return 0;
3114 }
3115 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3116 
3117 /*
3118  * Set of default routines for initialising struct proto_ops when
3119  * the protocol does not support a particular function. In certain
3120  * cases where it makes no sense for a protocol to have a "do nothing"
3121  * function, some default processing is provided.
3122  */
3123 
3124 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3125 {
3126 	return -EOPNOTSUPP;
3127 }
3128 EXPORT_SYMBOL(sock_no_bind);
3129 
3130 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3131 		    int len, int flags)
3132 {
3133 	return -EOPNOTSUPP;
3134 }
3135 EXPORT_SYMBOL(sock_no_connect);
3136 
3137 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3138 {
3139 	return -EOPNOTSUPP;
3140 }
3141 EXPORT_SYMBOL(sock_no_socketpair);
3142 
3143 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3144 		   bool kern)
3145 {
3146 	return -EOPNOTSUPP;
3147 }
3148 EXPORT_SYMBOL(sock_no_accept);
3149 
3150 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3151 		    int peer)
3152 {
3153 	return -EOPNOTSUPP;
3154 }
3155 EXPORT_SYMBOL(sock_no_getname);
3156 
3157 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3158 {
3159 	return -EOPNOTSUPP;
3160 }
3161 EXPORT_SYMBOL(sock_no_ioctl);
3162 
3163 int sock_no_listen(struct socket *sock, int backlog)
3164 {
3165 	return -EOPNOTSUPP;
3166 }
3167 EXPORT_SYMBOL(sock_no_listen);
3168 
3169 int sock_no_shutdown(struct socket *sock, int how)
3170 {
3171 	return -EOPNOTSUPP;
3172 }
3173 EXPORT_SYMBOL(sock_no_shutdown);
3174 
3175 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3176 {
3177 	return -EOPNOTSUPP;
3178 }
3179 EXPORT_SYMBOL(sock_no_sendmsg);
3180 
3181 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3182 {
3183 	return -EOPNOTSUPP;
3184 }
3185 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3186 
3187 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3188 		    int flags)
3189 {
3190 	return -EOPNOTSUPP;
3191 }
3192 EXPORT_SYMBOL(sock_no_recvmsg);
3193 
3194 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3195 {
3196 	/* Mirror missing mmap method error code */
3197 	return -ENODEV;
3198 }
3199 EXPORT_SYMBOL(sock_no_mmap);
3200 
3201 /*
3202  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3203  * various sock-based usage counts.
3204  */
3205 void __receive_sock(struct file *file)
3206 {
3207 	struct socket *sock;
3208 
3209 	sock = sock_from_file(file);
3210 	if (sock) {
3211 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3212 		sock_update_classid(&sock->sk->sk_cgrp_data);
3213 	}
3214 }
3215 
3216 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3217 {
3218 	ssize_t res;
3219 	struct msghdr msg = {.msg_flags = flags};
3220 	struct kvec iov;
3221 	char *kaddr = kmap(page);
3222 	iov.iov_base = kaddr + offset;
3223 	iov.iov_len = size;
3224 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3225 	kunmap(page);
3226 	return res;
3227 }
3228 EXPORT_SYMBOL(sock_no_sendpage);
3229 
3230 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3231 				int offset, size_t size, int flags)
3232 {
3233 	ssize_t res;
3234 	struct msghdr msg = {.msg_flags = flags};
3235 	struct kvec iov;
3236 	char *kaddr = kmap(page);
3237 
3238 	iov.iov_base = kaddr + offset;
3239 	iov.iov_len = size;
3240 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3241 	kunmap(page);
3242 	return res;
3243 }
3244 EXPORT_SYMBOL(sock_no_sendpage_locked);
3245 
3246 /*
3247  *	Default Socket Callbacks
3248  */
3249 
3250 static void sock_def_wakeup(struct sock *sk)
3251 {
3252 	struct socket_wq *wq;
3253 
3254 	rcu_read_lock();
3255 	wq = rcu_dereference(sk->sk_wq);
3256 	if (skwq_has_sleeper(wq))
3257 		wake_up_interruptible_all(&wq->wait);
3258 	rcu_read_unlock();
3259 }
3260 
3261 static void sock_def_error_report(struct sock *sk)
3262 {
3263 	struct socket_wq *wq;
3264 
3265 	rcu_read_lock();
3266 	wq = rcu_dereference(sk->sk_wq);
3267 	if (skwq_has_sleeper(wq))
3268 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3269 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3270 	rcu_read_unlock();
3271 }
3272 
3273 void sock_def_readable(struct sock *sk)
3274 {
3275 	struct socket_wq *wq;
3276 
3277 	trace_sk_data_ready(sk);
3278 
3279 	rcu_read_lock();
3280 	wq = rcu_dereference(sk->sk_wq);
3281 	if (skwq_has_sleeper(wq))
3282 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3283 						EPOLLRDNORM | EPOLLRDBAND);
3284 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3285 	rcu_read_unlock();
3286 }
3287 
3288 static void sock_def_write_space(struct sock *sk)
3289 {
3290 	struct socket_wq *wq;
3291 
3292 	rcu_read_lock();
3293 
3294 	/* Do not wake up a writer until he can make "significant"
3295 	 * progress.  --DaveM
3296 	 */
3297 	if (sock_writeable(sk)) {
3298 		wq = rcu_dereference(sk->sk_wq);
3299 		if (skwq_has_sleeper(wq))
3300 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3301 						EPOLLWRNORM | EPOLLWRBAND);
3302 
3303 		/* Should agree with poll, otherwise some programs break */
3304 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3305 	}
3306 
3307 	rcu_read_unlock();
3308 }
3309 
3310 /* An optimised version of sock_def_write_space(), should only be called
3311  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3312  * ->sk_wmem_alloc.
3313  */
3314 static void sock_def_write_space_wfree(struct sock *sk)
3315 {
3316 	/* Do not wake up a writer until he can make "significant"
3317 	 * progress.  --DaveM
3318 	 */
3319 	if (sock_writeable(sk)) {
3320 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3321 
3322 		/* rely on refcount_sub from sock_wfree() */
3323 		smp_mb__after_atomic();
3324 		if (wq && waitqueue_active(&wq->wait))
3325 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3326 						EPOLLWRNORM | EPOLLWRBAND);
3327 
3328 		/* Should agree with poll, otherwise some programs break */
3329 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3330 	}
3331 }
3332 
3333 static void sock_def_destruct(struct sock *sk)
3334 {
3335 }
3336 
3337 void sk_send_sigurg(struct sock *sk)
3338 {
3339 	if (sk->sk_socket && sk->sk_socket->file)
3340 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3341 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3342 }
3343 EXPORT_SYMBOL(sk_send_sigurg);
3344 
3345 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3346 		    unsigned long expires)
3347 {
3348 	if (!mod_timer(timer, expires))
3349 		sock_hold(sk);
3350 }
3351 EXPORT_SYMBOL(sk_reset_timer);
3352 
3353 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3354 {
3355 	if (del_timer(timer))
3356 		__sock_put(sk);
3357 }
3358 EXPORT_SYMBOL(sk_stop_timer);
3359 
3360 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3361 {
3362 	if (del_timer_sync(timer))
3363 		__sock_put(sk);
3364 }
3365 EXPORT_SYMBOL(sk_stop_timer_sync);
3366 
3367 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3368 {
3369 	sk_init_common(sk);
3370 	sk->sk_send_head	=	NULL;
3371 
3372 	timer_setup(&sk->sk_timer, NULL, 0);
3373 
3374 	sk->sk_allocation	=	GFP_KERNEL;
3375 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3376 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3377 	sk->sk_state		=	TCP_CLOSE;
3378 	sk->sk_use_task_frag	=	true;
3379 	sk_set_socket(sk, sock);
3380 
3381 	sock_set_flag(sk, SOCK_ZAPPED);
3382 
3383 	if (sock) {
3384 		sk->sk_type	=	sock->type;
3385 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3386 		sock->sk	=	sk;
3387 	} else {
3388 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3389 	}
3390 	sk->sk_uid	=	uid;
3391 
3392 	rwlock_init(&sk->sk_callback_lock);
3393 	if (sk->sk_kern_sock)
3394 		lockdep_set_class_and_name(
3395 			&sk->sk_callback_lock,
3396 			af_kern_callback_keys + sk->sk_family,
3397 			af_family_kern_clock_key_strings[sk->sk_family]);
3398 	else
3399 		lockdep_set_class_and_name(
3400 			&sk->sk_callback_lock,
3401 			af_callback_keys + sk->sk_family,
3402 			af_family_clock_key_strings[sk->sk_family]);
3403 
3404 	sk->sk_state_change	=	sock_def_wakeup;
3405 	sk->sk_data_ready	=	sock_def_readable;
3406 	sk->sk_write_space	=	sock_def_write_space;
3407 	sk->sk_error_report	=	sock_def_error_report;
3408 	sk->sk_destruct		=	sock_def_destruct;
3409 
3410 	sk->sk_frag.page	=	NULL;
3411 	sk->sk_frag.offset	=	0;
3412 	sk->sk_peek_off		=	-1;
3413 
3414 	sk->sk_peer_pid 	=	NULL;
3415 	sk->sk_peer_cred	=	NULL;
3416 	spin_lock_init(&sk->sk_peer_lock);
3417 
3418 	sk->sk_write_pending	=	0;
3419 	sk->sk_rcvlowat		=	1;
3420 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3421 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3422 
3423 	sk->sk_stamp = SK_DEFAULT_STAMP;
3424 #if BITS_PER_LONG==32
3425 	seqlock_init(&sk->sk_stamp_seq);
3426 #endif
3427 	atomic_set(&sk->sk_zckey, 0);
3428 
3429 #ifdef CONFIG_NET_RX_BUSY_POLL
3430 	sk->sk_napi_id		=	0;
3431 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3432 #endif
3433 
3434 	sk->sk_max_pacing_rate = ~0UL;
3435 	sk->sk_pacing_rate = ~0UL;
3436 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3437 	sk->sk_incoming_cpu = -1;
3438 
3439 	sk_rx_queue_clear(sk);
3440 	/*
3441 	 * Before updating sk_refcnt, we must commit prior changes to memory
3442 	 * (Documentation/RCU/rculist_nulls.rst for details)
3443 	 */
3444 	smp_wmb();
3445 	refcount_set(&sk->sk_refcnt, 1);
3446 	atomic_set(&sk->sk_drops, 0);
3447 }
3448 EXPORT_SYMBOL(sock_init_data_uid);
3449 
3450 void sock_init_data(struct socket *sock, struct sock *sk)
3451 {
3452 	kuid_t uid = sock ?
3453 		SOCK_INODE(sock)->i_uid :
3454 		make_kuid(sock_net(sk)->user_ns, 0);
3455 
3456 	sock_init_data_uid(sock, sk, uid);
3457 }
3458 EXPORT_SYMBOL(sock_init_data);
3459 
3460 void lock_sock_nested(struct sock *sk, int subclass)
3461 {
3462 	/* The sk_lock has mutex_lock() semantics here. */
3463 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3464 
3465 	might_sleep();
3466 	spin_lock_bh(&sk->sk_lock.slock);
3467 	if (sock_owned_by_user_nocheck(sk))
3468 		__lock_sock(sk);
3469 	sk->sk_lock.owned = 1;
3470 	spin_unlock_bh(&sk->sk_lock.slock);
3471 }
3472 EXPORT_SYMBOL(lock_sock_nested);
3473 
3474 void release_sock(struct sock *sk)
3475 {
3476 	spin_lock_bh(&sk->sk_lock.slock);
3477 	if (sk->sk_backlog.tail)
3478 		__release_sock(sk);
3479 
3480 	/* Warning : release_cb() might need to release sk ownership,
3481 	 * ie call sock_release_ownership(sk) before us.
3482 	 */
3483 	if (sk->sk_prot->release_cb)
3484 		sk->sk_prot->release_cb(sk);
3485 
3486 	sock_release_ownership(sk);
3487 	if (waitqueue_active(&sk->sk_lock.wq))
3488 		wake_up(&sk->sk_lock.wq);
3489 	spin_unlock_bh(&sk->sk_lock.slock);
3490 }
3491 EXPORT_SYMBOL(release_sock);
3492 
3493 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3494 {
3495 	might_sleep();
3496 	spin_lock_bh(&sk->sk_lock.slock);
3497 
3498 	if (!sock_owned_by_user_nocheck(sk)) {
3499 		/*
3500 		 * Fast path return with bottom halves disabled and
3501 		 * sock::sk_lock.slock held.
3502 		 *
3503 		 * The 'mutex' is not contended and holding
3504 		 * sock::sk_lock.slock prevents all other lockers to
3505 		 * proceed so the corresponding unlock_sock_fast() can
3506 		 * avoid the slow path of release_sock() completely and
3507 		 * just release slock.
3508 		 *
3509 		 * From a semantical POV this is equivalent to 'acquiring'
3510 		 * the 'mutex', hence the corresponding lockdep
3511 		 * mutex_release() has to happen in the fast path of
3512 		 * unlock_sock_fast().
3513 		 */
3514 		return false;
3515 	}
3516 
3517 	__lock_sock(sk);
3518 	sk->sk_lock.owned = 1;
3519 	__acquire(&sk->sk_lock.slock);
3520 	spin_unlock_bh(&sk->sk_lock.slock);
3521 	return true;
3522 }
3523 EXPORT_SYMBOL(__lock_sock_fast);
3524 
3525 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3526 		   bool timeval, bool time32)
3527 {
3528 	struct sock *sk = sock->sk;
3529 	struct timespec64 ts;
3530 
3531 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3532 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3533 	if (ts.tv_sec == -1)
3534 		return -ENOENT;
3535 	if (ts.tv_sec == 0) {
3536 		ktime_t kt = ktime_get_real();
3537 		sock_write_timestamp(sk, kt);
3538 		ts = ktime_to_timespec64(kt);
3539 	}
3540 
3541 	if (timeval)
3542 		ts.tv_nsec /= 1000;
3543 
3544 #ifdef CONFIG_COMPAT_32BIT_TIME
3545 	if (time32)
3546 		return put_old_timespec32(&ts, userstamp);
3547 #endif
3548 #ifdef CONFIG_SPARC64
3549 	/* beware of padding in sparc64 timeval */
3550 	if (timeval && !in_compat_syscall()) {
3551 		struct __kernel_old_timeval __user tv = {
3552 			.tv_sec = ts.tv_sec,
3553 			.tv_usec = ts.tv_nsec,
3554 		};
3555 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3556 			return -EFAULT;
3557 		return 0;
3558 	}
3559 #endif
3560 	return put_timespec64(&ts, userstamp);
3561 }
3562 EXPORT_SYMBOL(sock_gettstamp);
3563 
3564 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3565 {
3566 	if (!sock_flag(sk, flag)) {
3567 		unsigned long previous_flags = sk->sk_flags;
3568 
3569 		sock_set_flag(sk, flag);
3570 		/*
3571 		 * we just set one of the two flags which require net
3572 		 * time stamping, but time stamping might have been on
3573 		 * already because of the other one
3574 		 */
3575 		if (sock_needs_netstamp(sk) &&
3576 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3577 			net_enable_timestamp();
3578 	}
3579 }
3580 
3581 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3582 		       int level, int type)
3583 {
3584 	struct sock_exterr_skb *serr;
3585 	struct sk_buff *skb;
3586 	int copied, err;
3587 
3588 	err = -EAGAIN;
3589 	skb = sock_dequeue_err_skb(sk);
3590 	if (skb == NULL)
3591 		goto out;
3592 
3593 	copied = skb->len;
3594 	if (copied > len) {
3595 		msg->msg_flags |= MSG_TRUNC;
3596 		copied = len;
3597 	}
3598 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3599 	if (err)
3600 		goto out_free_skb;
3601 
3602 	sock_recv_timestamp(msg, sk, skb);
3603 
3604 	serr = SKB_EXT_ERR(skb);
3605 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3606 
3607 	msg->msg_flags |= MSG_ERRQUEUE;
3608 	err = copied;
3609 
3610 out_free_skb:
3611 	kfree_skb(skb);
3612 out:
3613 	return err;
3614 }
3615 EXPORT_SYMBOL(sock_recv_errqueue);
3616 
3617 /*
3618  *	Get a socket option on an socket.
3619  *
3620  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3621  *	asynchronous errors should be reported by getsockopt. We assume
3622  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3623  */
3624 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3625 			   char __user *optval, int __user *optlen)
3626 {
3627 	struct sock *sk = sock->sk;
3628 
3629 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3630 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3631 }
3632 EXPORT_SYMBOL(sock_common_getsockopt);
3633 
3634 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3635 			int flags)
3636 {
3637 	struct sock *sk = sock->sk;
3638 	int addr_len = 0;
3639 	int err;
3640 
3641 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3642 	if (err >= 0)
3643 		msg->msg_namelen = addr_len;
3644 	return err;
3645 }
3646 EXPORT_SYMBOL(sock_common_recvmsg);
3647 
3648 /*
3649  *	Set socket options on an inet socket.
3650  */
3651 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3652 			   sockptr_t optval, unsigned int optlen)
3653 {
3654 	struct sock *sk = sock->sk;
3655 
3656 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3657 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3658 }
3659 EXPORT_SYMBOL(sock_common_setsockopt);
3660 
3661 void sk_common_release(struct sock *sk)
3662 {
3663 	if (sk->sk_prot->destroy)
3664 		sk->sk_prot->destroy(sk);
3665 
3666 	/*
3667 	 * Observation: when sk_common_release is called, processes have
3668 	 * no access to socket. But net still has.
3669 	 * Step one, detach it from networking:
3670 	 *
3671 	 * A. Remove from hash tables.
3672 	 */
3673 
3674 	sk->sk_prot->unhash(sk);
3675 
3676 	/*
3677 	 * In this point socket cannot receive new packets, but it is possible
3678 	 * that some packets are in flight because some CPU runs receiver and
3679 	 * did hash table lookup before we unhashed socket. They will achieve
3680 	 * receive queue and will be purged by socket destructor.
3681 	 *
3682 	 * Also we still have packets pending on receive queue and probably,
3683 	 * our own packets waiting in device queues. sock_destroy will drain
3684 	 * receive queue, but transmitted packets will delay socket destruction
3685 	 * until the last reference will be released.
3686 	 */
3687 
3688 	sock_orphan(sk);
3689 
3690 	xfrm_sk_free_policy(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