xref: /openbmc/linux/net/core/sock.c (revision 9be08a27)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		Generic socket support routines. Memory allocators, socket lock/release
7  *		handler for protocols to use and generic option handler.
8  *
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  *		This program is free software; you can redistribute it and/or
87  *		modify it under the terms of the GNU General Public License
88  *		as published by the Free Software Foundation; either version
89  *		2 of the License, or (at your option) any later version.
90  */
91 
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93 
94 #include <asm/unaligned.h>
95 #include <linux/capability.h>
96 #include <linux/errno.h>
97 #include <linux/errqueue.h>
98 #include <linux/types.h>
99 #include <linux/socket.h>
100 #include <linux/in.h>
101 #include <linux/kernel.h>
102 #include <linux/module.h>
103 #include <linux/proc_fs.h>
104 #include <linux/seq_file.h>
105 #include <linux/sched.h>
106 #include <linux/sched/mm.h>
107 #include <linux/timer.h>
108 #include <linux/string.h>
109 #include <linux/sockios.h>
110 #include <linux/net.h>
111 #include <linux/mm.h>
112 #include <linux/slab.h>
113 #include <linux/interrupt.h>
114 #include <linux/poll.h>
115 #include <linux/tcp.h>
116 #include <linux/init.h>
117 #include <linux/highmem.h>
118 #include <linux/user_namespace.h>
119 #include <linux/static_key.h>
120 #include <linux/memcontrol.h>
121 #include <linux/prefetch.h>
122 
123 #include <linux/uaccess.h>
124 
125 #include <linux/netdevice.h>
126 #include <net/protocol.h>
127 #include <linux/skbuff.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <linux/net_tstamp.h>
132 #include <net/xfrm.h>
133 #include <linux/ipsec.h>
134 #include <net/cls_cgroup.h>
135 #include <net/netprio_cgroup.h>
136 #include <linux/sock_diag.h>
137 
138 #include <linux/filter.h>
139 #include <net/sock_reuseport.h>
140 
141 #include <trace/events/sock.h>
142 
143 #include <net/tcp.h>
144 #include <net/busy_poll.h>
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_inuse_add(struct net *net, int val);
150 
151 /**
152  * sk_ns_capable - General socket capability test
153  * @sk: Socket to use a capability on or through
154  * @user_ns: The user namespace of the capability to use
155  * @cap: The capability to use
156  *
157  * Test to see if the opener of the socket had when the socket was
158  * created and the current process has the capability @cap in the user
159  * namespace @user_ns.
160  */
161 bool sk_ns_capable(const struct sock *sk,
162 		   struct user_namespace *user_ns, int cap)
163 {
164 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
165 		ns_capable(user_ns, cap);
166 }
167 EXPORT_SYMBOL(sk_ns_capable);
168 
169 /**
170  * sk_capable - Socket global capability test
171  * @sk: Socket to use a capability on or through
172  * @cap: The global capability to use
173  *
174  * Test to see if the opener of the socket had when the socket was
175  * created and the current process has the capability @cap in all user
176  * namespaces.
177  */
178 bool sk_capable(const struct sock *sk, int cap)
179 {
180 	return sk_ns_capable(sk, &init_user_ns, cap);
181 }
182 EXPORT_SYMBOL(sk_capable);
183 
184 /**
185  * sk_net_capable - Network namespace socket capability test
186  * @sk: Socket to use a capability on or through
187  * @cap: The capability to use
188  *
189  * Test to see if the opener of the socket had when the socket was created
190  * and the current process has the capability @cap over the network namespace
191  * the socket is a member of.
192  */
193 bool sk_net_capable(const struct sock *sk, int cap)
194 {
195 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
196 }
197 EXPORT_SYMBOL(sk_net_capable);
198 
199 /*
200  * Each address family might have different locking rules, so we have
201  * one slock key per address family and separate keys for internal and
202  * userspace sockets.
203  */
204 static struct lock_class_key af_family_keys[AF_MAX];
205 static struct lock_class_key af_family_kern_keys[AF_MAX];
206 static struct lock_class_key af_family_slock_keys[AF_MAX];
207 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
208 
209 /*
210  * Make lock validator output more readable. (we pre-construct these
211  * strings build-time, so that runtime initialization of socket
212  * locks is fast):
213  */
214 
215 #define _sock_locks(x)						  \
216   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
217   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
218   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
219   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
220   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
221   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
222   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
223   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
224   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
225   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
226   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
227   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
228   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
229   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
230   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
231   x "AF_MAX"
232 
233 static const char *const af_family_key_strings[AF_MAX+1] = {
234 	_sock_locks("sk_lock-")
235 };
236 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
237 	_sock_locks("slock-")
238 };
239 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
240 	_sock_locks("clock-")
241 };
242 
243 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
244 	_sock_locks("k-sk_lock-")
245 };
246 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
247 	_sock_locks("k-slock-")
248 };
249 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
250 	_sock_locks("k-clock-")
251 };
252 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
253 	_sock_locks("rlock-")
254 };
255 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
256 	_sock_locks("wlock-")
257 };
258 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
259 	_sock_locks("elock-")
260 };
261 
262 /*
263  * sk_callback_lock and sk queues locking rules are per-address-family,
264  * so split the lock classes by using a per-AF key:
265  */
266 static struct lock_class_key af_callback_keys[AF_MAX];
267 static struct lock_class_key af_rlock_keys[AF_MAX];
268 static struct lock_class_key af_wlock_keys[AF_MAX];
269 static struct lock_class_key af_elock_keys[AF_MAX];
270 static struct lock_class_key af_kern_callback_keys[AF_MAX];
271 
272 /* Run time adjustable parameters. */
273 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
274 EXPORT_SYMBOL(sysctl_wmem_max);
275 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
276 EXPORT_SYMBOL(sysctl_rmem_max);
277 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
278 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
279 
280 /* Maximal space eaten by iovec or ancillary data plus some space */
281 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
282 EXPORT_SYMBOL(sysctl_optmem_max);
283 
284 int sysctl_tstamp_allow_data __read_mostly = 1;
285 
286 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
287 EXPORT_SYMBOL_GPL(memalloc_socks_key);
288 
289 /**
290  * sk_set_memalloc - sets %SOCK_MEMALLOC
291  * @sk: socket to set it on
292  *
293  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
294  * It's the responsibility of the admin to adjust min_free_kbytes
295  * to meet the requirements
296  */
297 void sk_set_memalloc(struct sock *sk)
298 {
299 	sock_set_flag(sk, SOCK_MEMALLOC);
300 	sk->sk_allocation |= __GFP_MEMALLOC;
301 	static_branch_inc(&memalloc_socks_key);
302 }
303 EXPORT_SYMBOL_GPL(sk_set_memalloc);
304 
305 void sk_clear_memalloc(struct sock *sk)
306 {
307 	sock_reset_flag(sk, SOCK_MEMALLOC);
308 	sk->sk_allocation &= ~__GFP_MEMALLOC;
309 	static_branch_dec(&memalloc_socks_key);
310 
311 	/*
312 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
313 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
314 	 * it has rmem allocations due to the last swapfile being deactivated
315 	 * but there is a risk that the socket is unusable due to exceeding
316 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
317 	 */
318 	sk_mem_reclaim(sk);
319 }
320 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
321 
322 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
323 {
324 	int ret;
325 	unsigned int noreclaim_flag;
326 
327 	/* these should have been dropped before queueing */
328 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
329 
330 	noreclaim_flag = memalloc_noreclaim_save();
331 	ret = sk->sk_backlog_rcv(sk, skb);
332 	memalloc_noreclaim_restore(noreclaim_flag);
333 
334 	return ret;
335 }
336 EXPORT_SYMBOL(__sk_backlog_rcv);
337 
338 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
339 {
340 	struct timeval tv;
341 
342 	if (optlen < sizeof(tv))
343 		return -EINVAL;
344 	if (copy_from_user(&tv, optval, sizeof(tv)))
345 		return -EFAULT;
346 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
347 		return -EDOM;
348 
349 	if (tv.tv_sec < 0) {
350 		static int warned __read_mostly;
351 
352 		*timeo_p = 0;
353 		if (warned < 10 && net_ratelimit()) {
354 			warned++;
355 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
356 				__func__, current->comm, task_pid_nr(current));
357 		}
358 		return 0;
359 	}
360 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
361 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
362 		return 0;
363 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
364 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ);
365 	return 0;
366 }
367 
368 static void sock_warn_obsolete_bsdism(const char *name)
369 {
370 	static int warned;
371 	static char warncomm[TASK_COMM_LEN];
372 	if (strcmp(warncomm, current->comm) && warned < 5) {
373 		strcpy(warncomm,  current->comm);
374 		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
375 			warncomm, name);
376 		warned++;
377 	}
378 }
379 
380 static bool sock_needs_netstamp(const struct sock *sk)
381 {
382 	switch (sk->sk_family) {
383 	case AF_UNSPEC:
384 	case AF_UNIX:
385 		return false;
386 	default:
387 		return true;
388 	}
389 }
390 
391 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
392 {
393 	if (sk->sk_flags & flags) {
394 		sk->sk_flags &= ~flags;
395 		if (sock_needs_netstamp(sk) &&
396 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
397 			net_disable_timestamp();
398 	}
399 }
400 
401 
402 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
403 {
404 	unsigned long flags;
405 	struct sk_buff_head *list = &sk->sk_receive_queue;
406 
407 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
408 		atomic_inc(&sk->sk_drops);
409 		trace_sock_rcvqueue_full(sk, skb);
410 		return -ENOMEM;
411 	}
412 
413 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
414 		atomic_inc(&sk->sk_drops);
415 		return -ENOBUFS;
416 	}
417 
418 	skb->dev = NULL;
419 	skb_set_owner_r(skb, sk);
420 
421 	/* we escape from rcu protected region, make sure we dont leak
422 	 * a norefcounted dst
423 	 */
424 	skb_dst_force(skb);
425 
426 	spin_lock_irqsave(&list->lock, flags);
427 	sock_skb_set_dropcount(sk, skb);
428 	__skb_queue_tail(list, skb);
429 	spin_unlock_irqrestore(&list->lock, flags);
430 
431 	if (!sock_flag(sk, SOCK_DEAD))
432 		sk->sk_data_ready(sk);
433 	return 0;
434 }
435 EXPORT_SYMBOL(__sock_queue_rcv_skb);
436 
437 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
438 {
439 	int err;
440 
441 	err = sk_filter(sk, skb);
442 	if (err)
443 		return err;
444 
445 	return __sock_queue_rcv_skb(sk, skb);
446 }
447 EXPORT_SYMBOL(sock_queue_rcv_skb);
448 
449 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
450 		     const int nested, unsigned int trim_cap, bool refcounted)
451 {
452 	int rc = NET_RX_SUCCESS;
453 
454 	if (sk_filter_trim_cap(sk, skb, trim_cap))
455 		goto discard_and_relse;
456 
457 	skb->dev = NULL;
458 
459 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
460 		atomic_inc(&sk->sk_drops);
461 		goto discard_and_relse;
462 	}
463 	if (nested)
464 		bh_lock_sock_nested(sk);
465 	else
466 		bh_lock_sock(sk);
467 	if (!sock_owned_by_user(sk)) {
468 		/*
469 		 * trylock + unlock semantics:
470 		 */
471 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
472 
473 		rc = sk_backlog_rcv(sk, skb);
474 
475 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
476 	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
477 		bh_unlock_sock(sk);
478 		atomic_inc(&sk->sk_drops);
479 		goto discard_and_relse;
480 	}
481 
482 	bh_unlock_sock(sk);
483 out:
484 	if (refcounted)
485 		sock_put(sk);
486 	return rc;
487 discard_and_relse:
488 	kfree_skb(skb);
489 	goto out;
490 }
491 EXPORT_SYMBOL(__sk_receive_skb);
492 
493 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
494 {
495 	struct dst_entry *dst = __sk_dst_get(sk);
496 
497 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
498 		sk_tx_queue_clear(sk);
499 		sk->sk_dst_pending_confirm = 0;
500 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
501 		dst_release(dst);
502 		return NULL;
503 	}
504 
505 	return dst;
506 }
507 EXPORT_SYMBOL(__sk_dst_check);
508 
509 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
510 {
511 	struct dst_entry *dst = sk_dst_get(sk);
512 
513 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
514 		sk_dst_reset(sk);
515 		dst_release(dst);
516 		return NULL;
517 	}
518 
519 	return dst;
520 }
521 EXPORT_SYMBOL(sk_dst_check);
522 
523 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
524 				int optlen)
525 {
526 	int ret = -ENOPROTOOPT;
527 #ifdef CONFIG_NETDEVICES
528 	struct net *net = sock_net(sk);
529 	char devname[IFNAMSIZ];
530 	int index;
531 
532 	/* Sorry... */
533 	ret = -EPERM;
534 	if (!ns_capable(net->user_ns, CAP_NET_RAW))
535 		goto out;
536 
537 	ret = -EINVAL;
538 	if (optlen < 0)
539 		goto out;
540 
541 	/* Bind this socket to a particular device like "eth0",
542 	 * as specified in the passed interface name. If the
543 	 * name is "" or the option length is zero the socket
544 	 * is not bound.
545 	 */
546 	if (optlen > IFNAMSIZ - 1)
547 		optlen = IFNAMSIZ - 1;
548 	memset(devname, 0, sizeof(devname));
549 
550 	ret = -EFAULT;
551 	if (copy_from_user(devname, optval, optlen))
552 		goto out;
553 
554 	index = 0;
555 	if (devname[0] != '\0') {
556 		struct net_device *dev;
557 
558 		rcu_read_lock();
559 		dev = dev_get_by_name_rcu(net, devname);
560 		if (dev)
561 			index = dev->ifindex;
562 		rcu_read_unlock();
563 		ret = -ENODEV;
564 		if (!dev)
565 			goto out;
566 	}
567 
568 	lock_sock(sk);
569 	sk->sk_bound_dev_if = index;
570 	sk_dst_reset(sk);
571 	release_sock(sk);
572 
573 	ret = 0;
574 
575 out:
576 #endif
577 
578 	return ret;
579 }
580 
581 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
582 				int __user *optlen, int len)
583 {
584 	int ret = -ENOPROTOOPT;
585 #ifdef CONFIG_NETDEVICES
586 	struct net *net = sock_net(sk);
587 	char devname[IFNAMSIZ];
588 
589 	if (sk->sk_bound_dev_if == 0) {
590 		len = 0;
591 		goto zero;
592 	}
593 
594 	ret = -EINVAL;
595 	if (len < IFNAMSIZ)
596 		goto out;
597 
598 	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
599 	if (ret)
600 		goto out;
601 
602 	len = strlen(devname) + 1;
603 
604 	ret = -EFAULT;
605 	if (copy_to_user(optval, devname, len))
606 		goto out;
607 
608 zero:
609 	ret = -EFAULT;
610 	if (put_user(len, optlen))
611 		goto out;
612 
613 	ret = 0;
614 
615 out:
616 #endif
617 
618 	return ret;
619 }
620 
621 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
622 {
623 	if (valbool)
624 		sock_set_flag(sk, bit);
625 	else
626 		sock_reset_flag(sk, bit);
627 }
628 
629 bool sk_mc_loop(struct sock *sk)
630 {
631 	if (dev_recursion_level())
632 		return false;
633 	if (!sk)
634 		return true;
635 	switch (sk->sk_family) {
636 	case AF_INET:
637 		return inet_sk(sk)->mc_loop;
638 #if IS_ENABLED(CONFIG_IPV6)
639 	case AF_INET6:
640 		return inet6_sk(sk)->mc_loop;
641 #endif
642 	}
643 	WARN_ON(1);
644 	return true;
645 }
646 EXPORT_SYMBOL(sk_mc_loop);
647 
648 /*
649  *	This is meant for all protocols to use and covers goings on
650  *	at the socket level. Everything here is generic.
651  */
652 
653 int sock_setsockopt(struct socket *sock, int level, int optname,
654 		    char __user *optval, unsigned int optlen)
655 {
656 	struct sock_txtime sk_txtime;
657 	struct sock *sk = sock->sk;
658 	int val;
659 	int valbool;
660 	struct linger ling;
661 	int ret = 0;
662 
663 	/*
664 	 *	Options without arguments
665 	 */
666 
667 	if (optname == SO_BINDTODEVICE)
668 		return sock_setbindtodevice(sk, optval, optlen);
669 
670 	if (optlen < sizeof(int))
671 		return -EINVAL;
672 
673 	if (get_user(val, (int __user *)optval))
674 		return -EFAULT;
675 
676 	valbool = val ? 1 : 0;
677 
678 	lock_sock(sk);
679 
680 	switch (optname) {
681 	case SO_DEBUG:
682 		if (val && !capable(CAP_NET_ADMIN))
683 			ret = -EACCES;
684 		else
685 			sock_valbool_flag(sk, SOCK_DBG, valbool);
686 		break;
687 	case SO_REUSEADDR:
688 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
689 		break;
690 	case SO_REUSEPORT:
691 		sk->sk_reuseport = valbool;
692 		break;
693 	case SO_TYPE:
694 	case SO_PROTOCOL:
695 	case SO_DOMAIN:
696 	case SO_ERROR:
697 		ret = -ENOPROTOOPT;
698 		break;
699 	case SO_DONTROUTE:
700 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
701 		break;
702 	case SO_BROADCAST:
703 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
704 		break;
705 	case SO_SNDBUF:
706 		/* Don't error on this BSD doesn't and if you think
707 		 * about it this is right. Otherwise apps have to
708 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
709 		 * are treated in BSD as hints
710 		 */
711 		val = min_t(u32, val, sysctl_wmem_max);
712 set_sndbuf:
713 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
714 		sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
715 		/* Wake up sending tasks if we upped the value. */
716 		sk->sk_write_space(sk);
717 		break;
718 
719 	case SO_SNDBUFFORCE:
720 		if (!capable(CAP_NET_ADMIN)) {
721 			ret = -EPERM;
722 			break;
723 		}
724 		goto set_sndbuf;
725 
726 	case SO_RCVBUF:
727 		/* Don't error on this BSD doesn't and if you think
728 		 * about it this is right. Otherwise apps have to
729 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
730 		 * are treated in BSD as hints
731 		 */
732 		val = min_t(u32, val, sysctl_rmem_max);
733 set_rcvbuf:
734 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
735 		/*
736 		 * We double it on the way in to account for
737 		 * "struct sk_buff" etc. overhead.   Applications
738 		 * assume that the SO_RCVBUF setting they make will
739 		 * allow that much actual data to be received on that
740 		 * socket.
741 		 *
742 		 * Applications are unaware that "struct sk_buff" and
743 		 * other overheads allocate from the receive buffer
744 		 * during socket buffer allocation.
745 		 *
746 		 * And after considering the possible alternatives,
747 		 * returning the value we actually used in getsockopt
748 		 * is the most desirable behavior.
749 		 */
750 		sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
751 		break;
752 
753 	case SO_RCVBUFFORCE:
754 		if (!capable(CAP_NET_ADMIN)) {
755 			ret = -EPERM;
756 			break;
757 		}
758 		goto set_rcvbuf;
759 
760 	case SO_KEEPALIVE:
761 		if (sk->sk_prot->keepalive)
762 			sk->sk_prot->keepalive(sk, valbool);
763 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
764 		break;
765 
766 	case SO_OOBINLINE:
767 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
768 		break;
769 
770 	case SO_NO_CHECK:
771 		sk->sk_no_check_tx = valbool;
772 		break;
773 
774 	case SO_PRIORITY:
775 		if ((val >= 0 && val <= 6) ||
776 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
777 			sk->sk_priority = val;
778 		else
779 			ret = -EPERM;
780 		break;
781 
782 	case SO_LINGER:
783 		if (optlen < sizeof(ling)) {
784 			ret = -EINVAL;	/* 1003.1g */
785 			break;
786 		}
787 		if (copy_from_user(&ling, optval, sizeof(ling))) {
788 			ret = -EFAULT;
789 			break;
790 		}
791 		if (!ling.l_onoff)
792 			sock_reset_flag(sk, SOCK_LINGER);
793 		else {
794 #if (BITS_PER_LONG == 32)
795 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
796 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
797 			else
798 #endif
799 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
800 			sock_set_flag(sk, SOCK_LINGER);
801 		}
802 		break;
803 
804 	case SO_BSDCOMPAT:
805 		sock_warn_obsolete_bsdism("setsockopt");
806 		break;
807 
808 	case SO_PASSCRED:
809 		if (valbool)
810 			set_bit(SOCK_PASSCRED, &sock->flags);
811 		else
812 			clear_bit(SOCK_PASSCRED, &sock->flags);
813 		break;
814 
815 	case SO_TIMESTAMP:
816 	case SO_TIMESTAMPNS:
817 		if (valbool)  {
818 			if (optname == SO_TIMESTAMP)
819 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
820 			else
821 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
822 			sock_set_flag(sk, SOCK_RCVTSTAMP);
823 			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
824 		} else {
825 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
826 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
827 		}
828 		break;
829 
830 	case SO_TIMESTAMPING:
831 		if (val & ~SOF_TIMESTAMPING_MASK) {
832 			ret = -EINVAL;
833 			break;
834 		}
835 
836 		if (val & SOF_TIMESTAMPING_OPT_ID &&
837 		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
838 			if (sk->sk_protocol == IPPROTO_TCP &&
839 			    sk->sk_type == SOCK_STREAM) {
840 				if ((1 << sk->sk_state) &
841 				    (TCPF_CLOSE | TCPF_LISTEN)) {
842 					ret = -EINVAL;
843 					break;
844 				}
845 				sk->sk_tskey = tcp_sk(sk)->snd_una;
846 			} else {
847 				sk->sk_tskey = 0;
848 			}
849 		}
850 
851 		if (val & SOF_TIMESTAMPING_OPT_STATS &&
852 		    !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
853 			ret = -EINVAL;
854 			break;
855 		}
856 
857 		sk->sk_tsflags = val;
858 		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
859 			sock_enable_timestamp(sk,
860 					      SOCK_TIMESTAMPING_RX_SOFTWARE);
861 		else
862 			sock_disable_timestamp(sk,
863 					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
864 		break;
865 
866 	case SO_RCVLOWAT:
867 		if (val < 0)
868 			val = INT_MAX;
869 		if (sock->ops->set_rcvlowat)
870 			ret = sock->ops->set_rcvlowat(sk, val);
871 		else
872 			sk->sk_rcvlowat = val ? : 1;
873 		break;
874 
875 	case SO_RCVTIMEO:
876 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
877 		break;
878 
879 	case SO_SNDTIMEO:
880 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
881 		break;
882 
883 	case SO_ATTACH_FILTER:
884 		ret = -EINVAL;
885 		if (optlen == sizeof(struct sock_fprog)) {
886 			struct sock_fprog fprog;
887 
888 			ret = -EFAULT;
889 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
890 				break;
891 
892 			ret = sk_attach_filter(&fprog, sk);
893 		}
894 		break;
895 
896 	case SO_ATTACH_BPF:
897 		ret = -EINVAL;
898 		if (optlen == sizeof(u32)) {
899 			u32 ufd;
900 
901 			ret = -EFAULT;
902 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
903 				break;
904 
905 			ret = sk_attach_bpf(ufd, sk);
906 		}
907 		break;
908 
909 	case SO_ATTACH_REUSEPORT_CBPF:
910 		ret = -EINVAL;
911 		if (optlen == sizeof(struct sock_fprog)) {
912 			struct sock_fprog fprog;
913 
914 			ret = -EFAULT;
915 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
916 				break;
917 
918 			ret = sk_reuseport_attach_filter(&fprog, sk);
919 		}
920 		break;
921 
922 	case SO_ATTACH_REUSEPORT_EBPF:
923 		ret = -EINVAL;
924 		if (optlen == sizeof(u32)) {
925 			u32 ufd;
926 
927 			ret = -EFAULT;
928 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
929 				break;
930 
931 			ret = sk_reuseport_attach_bpf(ufd, sk);
932 		}
933 		break;
934 
935 	case SO_DETACH_FILTER:
936 		ret = sk_detach_filter(sk);
937 		break;
938 
939 	case SO_LOCK_FILTER:
940 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
941 			ret = -EPERM;
942 		else
943 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
944 		break;
945 
946 	case SO_PASSSEC:
947 		if (valbool)
948 			set_bit(SOCK_PASSSEC, &sock->flags);
949 		else
950 			clear_bit(SOCK_PASSSEC, &sock->flags);
951 		break;
952 	case SO_MARK:
953 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
954 			ret = -EPERM;
955 		else
956 			sk->sk_mark = val;
957 		break;
958 
959 	case SO_RXQ_OVFL:
960 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
961 		break;
962 
963 	case SO_WIFI_STATUS:
964 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
965 		break;
966 
967 	case SO_PEEK_OFF:
968 		if (sock->ops->set_peek_off)
969 			ret = sock->ops->set_peek_off(sk, val);
970 		else
971 			ret = -EOPNOTSUPP;
972 		break;
973 
974 	case SO_NOFCS:
975 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
976 		break;
977 
978 	case SO_SELECT_ERR_QUEUE:
979 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
980 		break;
981 
982 #ifdef CONFIG_NET_RX_BUSY_POLL
983 	case SO_BUSY_POLL:
984 		/* allow unprivileged users to decrease the value */
985 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
986 			ret = -EPERM;
987 		else {
988 			if (val < 0)
989 				ret = -EINVAL;
990 			else
991 				sk->sk_ll_usec = val;
992 		}
993 		break;
994 #endif
995 
996 	case SO_MAX_PACING_RATE:
997 		if (val != ~0U)
998 			cmpxchg(&sk->sk_pacing_status,
999 				SK_PACING_NONE,
1000 				SK_PACING_NEEDED);
1001 		sk->sk_max_pacing_rate = val;
1002 		sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1003 					 sk->sk_max_pacing_rate);
1004 		break;
1005 
1006 	case SO_INCOMING_CPU:
1007 		sk->sk_incoming_cpu = val;
1008 		break;
1009 
1010 	case SO_CNX_ADVICE:
1011 		if (val == 1)
1012 			dst_negative_advice(sk);
1013 		break;
1014 
1015 	case SO_ZEROCOPY:
1016 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1017 			if (sk->sk_protocol != IPPROTO_TCP)
1018 				ret = -ENOTSUPP;
1019 		} else if (sk->sk_family != PF_RDS) {
1020 			ret = -ENOTSUPP;
1021 		}
1022 		if (!ret) {
1023 			if (val < 0 || val > 1)
1024 				ret = -EINVAL;
1025 			else
1026 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1027 		}
1028 		break;
1029 
1030 	case SO_TXTIME:
1031 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1032 			ret = -EPERM;
1033 		} else if (optlen != sizeof(struct sock_txtime)) {
1034 			ret = -EINVAL;
1035 		} else if (copy_from_user(&sk_txtime, optval,
1036 			   sizeof(struct sock_txtime))) {
1037 			ret = -EFAULT;
1038 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1039 			ret = -EINVAL;
1040 		} else {
1041 			sock_valbool_flag(sk, SOCK_TXTIME, true);
1042 			sk->sk_clockid = sk_txtime.clockid;
1043 			sk->sk_txtime_deadline_mode =
1044 				!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1045 			sk->sk_txtime_report_errors =
1046 				!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1047 		}
1048 		break;
1049 
1050 	default:
1051 		ret = -ENOPROTOOPT;
1052 		break;
1053 	}
1054 	release_sock(sk);
1055 	return ret;
1056 }
1057 EXPORT_SYMBOL(sock_setsockopt);
1058 
1059 
1060 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1061 			  struct ucred *ucred)
1062 {
1063 	ucred->pid = pid_vnr(pid);
1064 	ucred->uid = ucred->gid = -1;
1065 	if (cred) {
1066 		struct user_namespace *current_ns = current_user_ns();
1067 
1068 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1069 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1070 	}
1071 }
1072 
1073 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1074 {
1075 	struct user_namespace *user_ns = current_user_ns();
1076 	int i;
1077 
1078 	for (i = 0; i < src->ngroups; i++)
1079 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1080 			return -EFAULT;
1081 
1082 	return 0;
1083 }
1084 
1085 int sock_getsockopt(struct socket *sock, int level, int optname,
1086 		    char __user *optval, int __user *optlen)
1087 {
1088 	struct sock *sk = sock->sk;
1089 
1090 	union {
1091 		int val;
1092 		u64 val64;
1093 		struct linger ling;
1094 		struct timeval tm;
1095 		struct sock_txtime txtime;
1096 	} v;
1097 
1098 	int lv = sizeof(int);
1099 	int len;
1100 
1101 	if (get_user(len, optlen))
1102 		return -EFAULT;
1103 	if (len < 0)
1104 		return -EINVAL;
1105 
1106 	memset(&v, 0, sizeof(v));
1107 
1108 	switch (optname) {
1109 	case SO_DEBUG:
1110 		v.val = sock_flag(sk, SOCK_DBG);
1111 		break;
1112 
1113 	case SO_DONTROUTE:
1114 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1115 		break;
1116 
1117 	case SO_BROADCAST:
1118 		v.val = sock_flag(sk, SOCK_BROADCAST);
1119 		break;
1120 
1121 	case SO_SNDBUF:
1122 		v.val = sk->sk_sndbuf;
1123 		break;
1124 
1125 	case SO_RCVBUF:
1126 		v.val = sk->sk_rcvbuf;
1127 		break;
1128 
1129 	case SO_REUSEADDR:
1130 		v.val = sk->sk_reuse;
1131 		break;
1132 
1133 	case SO_REUSEPORT:
1134 		v.val = sk->sk_reuseport;
1135 		break;
1136 
1137 	case SO_KEEPALIVE:
1138 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1139 		break;
1140 
1141 	case SO_TYPE:
1142 		v.val = sk->sk_type;
1143 		break;
1144 
1145 	case SO_PROTOCOL:
1146 		v.val = sk->sk_protocol;
1147 		break;
1148 
1149 	case SO_DOMAIN:
1150 		v.val = sk->sk_family;
1151 		break;
1152 
1153 	case SO_ERROR:
1154 		v.val = -sock_error(sk);
1155 		if (v.val == 0)
1156 			v.val = xchg(&sk->sk_err_soft, 0);
1157 		break;
1158 
1159 	case SO_OOBINLINE:
1160 		v.val = sock_flag(sk, SOCK_URGINLINE);
1161 		break;
1162 
1163 	case SO_NO_CHECK:
1164 		v.val = sk->sk_no_check_tx;
1165 		break;
1166 
1167 	case SO_PRIORITY:
1168 		v.val = sk->sk_priority;
1169 		break;
1170 
1171 	case SO_LINGER:
1172 		lv		= sizeof(v.ling);
1173 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1174 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1175 		break;
1176 
1177 	case SO_BSDCOMPAT:
1178 		sock_warn_obsolete_bsdism("getsockopt");
1179 		break;
1180 
1181 	case SO_TIMESTAMP:
1182 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1183 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1184 		break;
1185 
1186 	case SO_TIMESTAMPNS:
1187 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1188 		break;
1189 
1190 	case SO_TIMESTAMPING:
1191 		v.val = sk->sk_tsflags;
1192 		break;
1193 
1194 	case SO_RCVTIMEO:
1195 		lv = sizeof(struct timeval);
1196 		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1197 			v.tm.tv_sec = 0;
1198 			v.tm.tv_usec = 0;
1199 		} else {
1200 			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1201 			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
1202 		}
1203 		break;
1204 
1205 	case SO_SNDTIMEO:
1206 		lv = sizeof(struct timeval);
1207 		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1208 			v.tm.tv_sec = 0;
1209 			v.tm.tv_usec = 0;
1210 		} else {
1211 			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1212 			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1213 		}
1214 		break;
1215 
1216 	case SO_RCVLOWAT:
1217 		v.val = sk->sk_rcvlowat;
1218 		break;
1219 
1220 	case SO_SNDLOWAT:
1221 		v.val = 1;
1222 		break;
1223 
1224 	case SO_PASSCRED:
1225 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1226 		break;
1227 
1228 	case SO_PEERCRED:
1229 	{
1230 		struct ucred peercred;
1231 		if (len > sizeof(peercred))
1232 			len = sizeof(peercred);
1233 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1234 		if (copy_to_user(optval, &peercred, len))
1235 			return -EFAULT;
1236 		goto lenout;
1237 	}
1238 
1239 	case SO_PEERGROUPS:
1240 	{
1241 		int ret, n;
1242 
1243 		if (!sk->sk_peer_cred)
1244 			return -ENODATA;
1245 
1246 		n = sk->sk_peer_cred->group_info->ngroups;
1247 		if (len < n * sizeof(gid_t)) {
1248 			len = n * sizeof(gid_t);
1249 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1250 		}
1251 		len = n * sizeof(gid_t);
1252 
1253 		ret = groups_to_user((gid_t __user *)optval,
1254 				     sk->sk_peer_cred->group_info);
1255 		if (ret)
1256 			return ret;
1257 		goto lenout;
1258 	}
1259 
1260 	case SO_PEERNAME:
1261 	{
1262 		char address[128];
1263 
1264 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1265 		if (lv < 0)
1266 			return -ENOTCONN;
1267 		if (lv < len)
1268 			return -EINVAL;
1269 		if (copy_to_user(optval, address, len))
1270 			return -EFAULT;
1271 		goto lenout;
1272 	}
1273 
1274 	/* Dubious BSD thing... Probably nobody even uses it, but
1275 	 * the UNIX standard wants it for whatever reason... -DaveM
1276 	 */
1277 	case SO_ACCEPTCONN:
1278 		v.val = sk->sk_state == TCP_LISTEN;
1279 		break;
1280 
1281 	case SO_PASSSEC:
1282 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1283 		break;
1284 
1285 	case SO_PEERSEC:
1286 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1287 
1288 	case SO_MARK:
1289 		v.val = sk->sk_mark;
1290 		break;
1291 
1292 	case SO_RXQ_OVFL:
1293 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1294 		break;
1295 
1296 	case SO_WIFI_STATUS:
1297 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1298 		break;
1299 
1300 	case SO_PEEK_OFF:
1301 		if (!sock->ops->set_peek_off)
1302 			return -EOPNOTSUPP;
1303 
1304 		v.val = sk->sk_peek_off;
1305 		break;
1306 	case SO_NOFCS:
1307 		v.val = sock_flag(sk, SOCK_NOFCS);
1308 		break;
1309 
1310 	case SO_BINDTODEVICE:
1311 		return sock_getbindtodevice(sk, optval, optlen, len);
1312 
1313 	case SO_GET_FILTER:
1314 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1315 		if (len < 0)
1316 			return len;
1317 
1318 		goto lenout;
1319 
1320 	case SO_LOCK_FILTER:
1321 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1322 		break;
1323 
1324 	case SO_BPF_EXTENSIONS:
1325 		v.val = bpf_tell_extensions();
1326 		break;
1327 
1328 	case SO_SELECT_ERR_QUEUE:
1329 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1330 		break;
1331 
1332 #ifdef CONFIG_NET_RX_BUSY_POLL
1333 	case SO_BUSY_POLL:
1334 		v.val = sk->sk_ll_usec;
1335 		break;
1336 #endif
1337 
1338 	case SO_MAX_PACING_RATE:
1339 		v.val = sk->sk_max_pacing_rate;
1340 		break;
1341 
1342 	case SO_INCOMING_CPU:
1343 		v.val = sk->sk_incoming_cpu;
1344 		break;
1345 
1346 	case SO_MEMINFO:
1347 	{
1348 		u32 meminfo[SK_MEMINFO_VARS];
1349 
1350 		if (get_user(len, optlen))
1351 			return -EFAULT;
1352 
1353 		sk_get_meminfo(sk, meminfo);
1354 
1355 		len = min_t(unsigned int, len, sizeof(meminfo));
1356 		if (copy_to_user(optval, &meminfo, len))
1357 			return -EFAULT;
1358 
1359 		goto lenout;
1360 	}
1361 
1362 #ifdef CONFIG_NET_RX_BUSY_POLL
1363 	case SO_INCOMING_NAPI_ID:
1364 		v.val = READ_ONCE(sk->sk_napi_id);
1365 
1366 		/* aggregate non-NAPI IDs down to 0 */
1367 		if (v.val < MIN_NAPI_ID)
1368 			v.val = 0;
1369 
1370 		break;
1371 #endif
1372 
1373 	case SO_COOKIE:
1374 		lv = sizeof(u64);
1375 		if (len < lv)
1376 			return -EINVAL;
1377 		v.val64 = sock_gen_cookie(sk);
1378 		break;
1379 
1380 	case SO_ZEROCOPY:
1381 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1382 		break;
1383 
1384 	case SO_TXTIME:
1385 		lv = sizeof(v.txtime);
1386 		v.txtime.clockid = sk->sk_clockid;
1387 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1388 				  SOF_TXTIME_DEADLINE_MODE : 0;
1389 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1390 				  SOF_TXTIME_REPORT_ERRORS : 0;
1391 		break;
1392 
1393 	default:
1394 		/* We implement the SO_SNDLOWAT etc to not be settable
1395 		 * (1003.1g 7).
1396 		 */
1397 		return -ENOPROTOOPT;
1398 	}
1399 
1400 	if (len > lv)
1401 		len = lv;
1402 	if (copy_to_user(optval, &v, len))
1403 		return -EFAULT;
1404 lenout:
1405 	if (put_user(len, optlen))
1406 		return -EFAULT;
1407 	return 0;
1408 }
1409 
1410 /*
1411  * Initialize an sk_lock.
1412  *
1413  * (We also register the sk_lock with the lock validator.)
1414  */
1415 static inline void sock_lock_init(struct sock *sk)
1416 {
1417 	if (sk->sk_kern_sock)
1418 		sock_lock_init_class_and_name(
1419 			sk,
1420 			af_family_kern_slock_key_strings[sk->sk_family],
1421 			af_family_kern_slock_keys + sk->sk_family,
1422 			af_family_kern_key_strings[sk->sk_family],
1423 			af_family_kern_keys + sk->sk_family);
1424 	else
1425 		sock_lock_init_class_and_name(
1426 			sk,
1427 			af_family_slock_key_strings[sk->sk_family],
1428 			af_family_slock_keys + sk->sk_family,
1429 			af_family_key_strings[sk->sk_family],
1430 			af_family_keys + sk->sk_family);
1431 }
1432 
1433 /*
1434  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1435  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1436  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1437  */
1438 static void sock_copy(struct sock *nsk, const struct sock *osk)
1439 {
1440 #ifdef CONFIG_SECURITY_NETWORK
1441 	void *sptr = nsk->sk_security;
1442 #endif
1443 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1444 
1445 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1446 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1447 
1448 #ifdef CONFIG_SECURITY_NETWORK
1449 	nsk->sk_security = sptr;
1450 	security_sk_clone(osk, nsk);
1451 #endif
1452 }
1453 
1454 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1455 		int family)
1456 {
1457 	struct sock *sk;
1458 	struct kmem_cache *slab;
1459 
1460 	slab = prot->slab;
1461 	if (slab != NULL) {
1462 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1463 		if (!sk)
1464 			return sk;
1465 		if (priority & __GFP_ZERO)
1466 			sk_prot_clear_nulls(sk, prot->obj_size);
1467 	} else
1468 		sk = kmalloc(prot->obj_size, priority);
1469 
1470 	if (sk != NULL) {
1471 		if (security_sk_alloc(sk, family, priority))
1472 			goto out_free;
1473 
1474 		if (!try_module_get(prot->owner))
1475 			goto out_free_sec;
1476 		sk_tx_queue_clear(sk);
1477 	}
1478 
1479 	return sk;
1480 
1481 out_free_sec:
1482 	security_sk_free(sk);
1483 out_free:
1484 	if (slab != NULL)
1485 		kmem_cache_free(slab, sk);
1486 	else
1487 		kfree(sk);
1488 	return NULL;
1489 }
1490 
1491 static void sk_prot_free(struct proto *prot, struct sock *sk)
1492 {
1493 	struct kmem_cache *slab;
1494 	struct module *owner;
1495 
1496 	owner = prot->owner;
1497 	slab = prot->slab;
1498 
1499 	cgroup_sk_free(&sk->sk_cgrp_data);
1500 	mem_cgroup_sk_free(sk);
1501 	security_sk_free(sk);
1502 	if (slab != NULL)
1503 		kmem_cache_free(slab, sk);
1504 	else
1505 		kfree(sk);
1506 	module_put(owner);
1507 }
1508 
1509 /**
1510  *	sk_alloc - All socket objects are allocated here
1511  *	@net: the applicable net namespace
1512  *	@family: protocol family
1513  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1514  *	@prot: struct proto associated with this new sock instance
1515  *	@kern: is this to be a kernel socket?
1516  */
1517 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1518 		      struct proto *prot, int kern)
1519 {
1520 	struct sock *sk;
1521 
1522 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1523 	if (sk) {
1524 		sk->sk_family = family;
1525 		/*
1526 		 * See comment in struct sock definition to understand
1527 		 * why we need sk_prot_creator -acme
1528 		 */
1529 		sk->sk_prot = sk->sk_prot_creator = prot;
1530 		sk->sk_kern_sock = kern;
1531 		sock_lock_init(sk);
1532 		sk->sk_net_refcnt = kern ? 0 : 1;
1533 		if (likely(sk->sk_net_refcnt)) {
1534 			get_net(net);
1535 			sock_inuse_add(net, 1);
1536 		}
1537 
1538 		sock_net_set(sk, net);
1539 		refcount_set(&sk->sk_wmem_alloc, 1);
1540 
1541 		mem_cgroup_sk_alloc(sk);
1542 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1543 		sock_update_classid(&sk->sk_cgrp_data);
1544 		sock_update_netprioidx(&sk->sk_cgrp_data);
1545 	}
1546 
1547 	return sk;
1548 }
1549 EXPORT_SYMBOL(sk_alloc);
1550 
1551 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1552  * grace period. This is the case for UDP sockets and TCP listeners.
1553  */
1554 static void __sk_destruct(struct rcu_head *head)
1555 {
1556 	struct sock *sk = container_of(head, struct sock, sk_rcu);
1557 	struct sk_filter *filter;
1558 
1559 	if (sk->sk_destruct)
1560 		sk->sk_destruct(sk);
1561 
1562 	filter = rcu_dereference_check(sk->sk_filter,
1563 				       refcount_read(&sk->sk_wmem_alloc) == 0);
1564 	if (filter) {
1565 		sk_filter_uncharge(sk, filter);
1566 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1567 	}
1568 	if (rcu_access_pointer(sk->sk_reuseport_cb))
1569 		reuseport_detach_sock(sk);
1570 
1571 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1572 
1573 	if (atomic_read(&sk->sk_omem_alloc))
1574 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1575 			 __func__, atomic_read(&sk->sk_omem_alloc));
1576 
1577 	if (sk->sk_frag.page) {
1578 		put_page(sk->sk_frag.page);
1579 		sk->sk_frag.page = NULL;
1580 	}
1581 
1582 	if (sk->sk_peer_cred)
1583 		put_cred(sk->sk_peer_cred);
1584 	put_pid(sk->sk_peer_pid);
1585 	if (likely(sk->sk_net_refcnt))
1586 		put_net(sock_net(sk));
1587 	sk_prot_free(sk->sk_prot_creator, sk);
1588 }
1589 
1590 void sk_destruct(struct sock *sk)
1591 {
1592 	if (sock_flag(sk, SOCK_RCU_FREE))
1593 		call_rcu(&sk->sk_rcu, __sk_destruct);
1594 	else
1595 		__sk_destruct(&sk->sk_rcu);
1596 }
1597 
1598 static void __sk_free(struct sock *sk)
1599 {
1600 	if (likely(sk->sk_net_refcnt))
1601 		sock_inuse_add(sock_net(sk), -1);
1602 
1603 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1604 		sock_diag_broadcast_destroy(sk);
1605 	else
1606 		sk_destruct(sk);
1607 }
1608 
1609 void sk_free(struct sock *sk)
1610 {
1611 	/*
1612 	 * We subtract one from sk_wmem_alloc and can know if
1613 	 * some packets are still in some tx queue.
1614 	 * If not null, sock_wfree() will call __sk_free(sk) later
1615 	 */
1616 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1617 		__sk_free(sk);
1618 }
1619 EXPORT_SYMBOL(sk_free);
1620 
1621 static void sk_init_common(struct sock *sk)
1622 {
1623 	skb_queue_head_init(&sk->sk_receive_queue);
1624 	skb_queue_head_init(&sk->sk_write_queue);
1625 	skb_queue_head_init(&sk->sk_error_queue);
1626 
1627 	rwlock_init(&sk->sk_callback_lock);
1628 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1629 			af_rlock_keys + sk->sk_family,
1630 			af_family_rlock_key_strings[sk->sk_family]);
1631 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1632 			af_wlock_keys + sk->sk_family,
1633 			af_family_wlock_key_strings[sk->sk_family]);
1634 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1635 			af_elock_keys + sk->sk_family,
1636 			af_family_elock_key_strings[sk->sk_family]);
1637 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1638 			af_callback_keys + sk->sk_family,
1639 			af_family_clock_key_strings[sk->sk_family]);
1640 }
1641 
1642 /**
1643  *	sk_clone_lock - clone a socket, and lock its clone
1644  *	@sk: the socket to clone
1645  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1646  *
1647  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1648  */
1649 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1650 {
1651 	struct sock *newsk;
1652 	bool is_charged = true;
1653 
1654 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1655 	if (newsk != NULL) {
1656 		struct sk_filter *filter;
1657 
1658 		sock_copy(newsk, sk);
1659 
1660 		newsk->sk_prot_creator = sk->sk_prot;
1661 
1662 		/* SANITY */
1663 		if (likely(newsk->sk_net_refcnt))
1664 			get_net(sock_net(newsk));
1665 		sk_node_init(&newsk->sk_node);
1666 		sock_lock_init(newsk);
1667 		bh_lock_sock(newsk);
1668 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1669 		newsk->sk_backlog.len = 0;
1670 
1671 		atomic_set(&newsk->sk_rmem_alloc, 0);
1672 		/*
1673 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1674 		 */
1675 		refcount_set(&newsk->sk_wmem_alloc, 1);
1676 		atomic_set(&newsk->sk_omem_alloc, 0);
1677 		sk_init_common(newsk);
1678 
1679 		newsk->sk_dst_cache	= NULL;
1680 		newsk->sk_dst_pending_confirm = 0;
1681 		newsk->sk_wmem_queued	= 0;
1682 		newsk->sk_forward_alloc = 0;
1683 		atomic_set(&newsk->sk_drops, 0);
1684 		newsk->sk_send_head	= NULL;
1685 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1686 		atomic_set(&newsk->sk_zckey, 0);
1687 
1688 		sock_reset_flag(newsk, SOCK_DONE);
1689 		mem_cgroup_sk_alloc(newsk);
1690 		cgroup_sk_alloc(&newsk->sk_cgrp_data);
1691 
1692 		rcu_read_lock();
1693 		filter = rcu_dereference(sk->sk_filter);
1694 		if (filter != NULL)
1695 			/* though it's an empty new sock, the charging may fail
1696 			 * if sysctl_optmem_max was changed between creation of
1697 			 * original socket and cloning
1698 			 */
1699 			is_charged = sk_filter_charge(newsk, filter);
1700 		RCU_INIT_POINTER(newsk->sk_filter, filter);
1701 		rcu_read_unlock();
1702 
1703 		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1704 			/* We need to make sure that we don't uncharge the new
1705 			 * socket if we couldn't charge it in the first place
1706 			 * as otherwise we uncharge the parent's filter.
1707 			 */
1708 			if (!is_charged)
1709 				RCU_INIT_POINTER(newsk->sk_filter, NULL);
1710 			sk_free_unlock_clone(newsk);
1711 			newsk = NULL;
1712 			goto out;
1713 		}
1714 		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1715 
1716 		newsk->sk_err	   = 0;
1717 		newsk->sk_err_soft = 0;
1718 		newsk->sk_priority = 0;
1719 		newsk->sk_incoming_cpu = raw_smp_processor_id();
1720 		atomic64_set(&newsk->sk_cookie, 0);
1721 		if (likely(newsk->sk_net_refcnt))
1722 			sock_inuse_add(sock_net(newsk), 1);
1723 
1724 		/*
1725 		 * Before updating sk_refcnt, we must commit prior changes to memory
1726 		 * (Documentation/RCU/rculist_nulls.txt for details)
1727 		 */
1728 		smp_wmb();
1729 		refcount_set(&newsk->sk_refcnt, 2);
1730 
1731 		/*
1732 		 * Increment the counter in the same struct proto as the master
1733 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1734 		 * is the same as sk->sk_prot->socks, as this field was copied
1735 		 * with memcpy).
1736 		 *
1737 		 * This _changes_ the previous behaviour, where
1738 		 * tcp_create_openreq_child always was incrementing the
1739 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1740 		 * to be taken into account in all callers. -acme
1741 		 */
1742 		sk_refcnt_debug_inc(newsk);
1743 		sk_set_socket(newsk, NULL);
1744 		newsk->sk_wq = NULL;
1745 
1746 		if (newsk->sk_prot->sockets_allocated)
1747 			sk_sockets_allocated_inc(newsk);
1748 
1749 		if (sock_needs_netstamp(sk) &&
1750 		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1751 			net_enable_timestamp();
1752 	}
1753 out:
1754 	return newsk;
1755 }
1756 EXPORT_SYMBOL_GPL(sk_clone_lock);
1757 
1758 void sk_free_unlock_clone(struct sock *sk)
1759 {
1760 	/* It is still raw copy of parent, so invalidate
1761 	 * destructor and make plain sk_free() */
1762 	sk->sk_destruct = NULL;
1763 	bh_unlock_sock(sk);
1764 	sk_free(sk);
1765 }
1766 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1767 
1768 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1769 {
1770 	u32 max_segs = 1;
1771 
1772 	sk_dst_set(sk, dst);
1773 	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
1774 	if (sk->sk_route_caps & NETIF_F_GSO)
1775 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1776 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1777 	if (sk_can_gso(sk)) {
1778 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1779 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1780 		} else {
1781 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1782 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1783 			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1784 		}
1785 	}
1786 	sk->sk_gso_max_segs = max_segs;
1787 }
1788 EXPORT_SYMBOL_GPL(sk_setup_caps);
1789 
1790 /*
1791  *	Simple resource managers for sockets.
1792  */
1793 
1794 
1795 /*
1796  * Write buffer destructor automatically called from kfree_skb.
1797  */
1798 void sock_wfree(struct sk_buff *skb)
1799 {
1800 	struct sock *sk = skb->sk;
1801 	unsigned int len = skb->truesize;
1802 
1803 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1804 		/*
1805 		 * Keep a reference on sk_wmem_alloc, this will be released
1806 		 * after sk_write_space() call
1807 		 */
1808 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1809 		sk->sk_write_space(sk);
1810 		len = 1;
1811 	}
1812 	/*
1813 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1814 	 * could not do because of in-flight packets
1815 	 */
1816 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1817 		__sk_free(sk);
1818 }
1819 EXPORT_SYMBOL(sock_wfree);
1820 
1821 /* This variant of sock_wfree() is used by TCP,
1822  * since it sets SOCK_USE_WRITE_QUEUE.
1823  */
1824 void __sock_wfree(struct sk_buff *skb)
1825 {
1826 	struct sock *sk = skb->sk;
1827 
1828 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1829 		__sk_free(sk);
1830 }
1831 
1832 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1833 {
1834 	skb_orphan(skb);
1835 	skb->sk = sk;
1836 #ifdef CONFIG_INET
1837 	if (unlikely(!sk_fullsock(sk))) {
1838 		skb->destructor = sock_edemux;
1839 		sock_hold(sk);
1840 		return;
1841 	}
1842 #endif
1843 	skb->destructor = sock_wfree;
1844 	skb_set_hash_from_sk(skb, sk);
1845 	/*
1846 	 * We used to take a refcount on sk, but following operation
1847 	 * is enough to guarantee sk_free() wont free this sock until
1848 	 * all in-flight packets are completed
1849 	 */
1850 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1851 }
1852 EXPORT_SYMBOL(skb_set_owner_w);
1853 
1854 /* This helper is used by netem, as it can hold packets in its
1855  * delay queue. We want to allow the owner socket to send more
1856  * packets, as if they were already TX completed by a typical driver.
1857  * But we also want to keep skb->sk set because some packet schedulers
1858  * rely on it (sch_fq for example).
1859  */
1860 void skb_orphan_partial(struct sk_buff *skb)
1861 {
1862 	if (skb_is_tcp_pure_ack(skb))
1863 		return;
1864 
1865 	if (skb->destructor == sock_wfree
1866 #ifdef CONFIG_INET
1867 	    || skb->destructor == tcp_wfree
1868 #endif
1869 		) {
1870 		struct sock *sk = skb->sk;
1871 
1872 		if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1873 			WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
1874 			skb->destructor = sock_efree;
1875 		}
1876 	} else {
1877 		skb_orphan(skb);
1878 	}
1879 }
1880 EXPORT_SYMBOL(skb_orphan_partial);
1881 
1882 /*
1883  * Read buffer destructor automatically called from kfree_skb.
1884  */
1885 void sock_rfree(struct sk_buff *skb)
1886 {
1887 	struct sock *sk = skb->sk;
1888 	unsigned int len = skb->truesize;
1889 
1890 	atomic_sub(len, &sk->sk_rmem_alloc);
1891 	sk_mem_uncharge(sk, len);
1892 }
1893 EXPORT_SYMBOL(sock_rfree);
1894 
1895 /*
1896  * Buffer destructor for skbs that are not used directly in read or write
1897  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1898  */
1899 void sock_efree(struct sk_buff *skb)
1900 {
1901 	sock_put(skb->sk);
1902 }
1903 EXPORT_SYMBOL(sock_efree);
1904 
1905 kuid_t sock_i_uid(struct sock *sk)
1906 {
1907 	kuid_t uid;
1908 
1909 	read_lock_bh(&sk->sk_callback_lock);
1910 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1911 	read_unlock_bh(&sk->sk_callback_lock);
1912 	return uid;
1913 }
1914 EXPORT_SYMBOL(sock_i_uid);
1915 
1916 unsigned long sock_i_ino(struct sock *sk)
1917 {
1918 	unsigned long ino;
1919 
1920 	read_lock_bh(&sk->sk_callback_lock);
1921 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1922 	read_unlock_bh(&sk->sk_callback_lock);
1923 	return ino;
1924 }
1925 EXPORT_SYMBOL(sock_i_ino);
1926 
1927 /*
1928  * Allocate a skb from the socket's send buffer.
1929  */
1930 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1931 			     gfp_t priority)
1932 {
1933 	if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1934 		struct sk_buff *skb = alloc_skb(size, priority);
1935 		if (skb) {
1936 			skb_set_owner_w(skb, sk);
1937 			return skb;
1938 		}
1939 	}
1940 	return NULL;
1941 }
1942 EXPORT_SYMBOL(sock_wmalloc);
1943 
1944 static void sock_ofree(struct sk_buff *skb)
1945 {
1946 	struct sock *sk = skb->sk;
1947 
1948 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
1949 }
1950 
1951 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1952 			     gfp_t priority)
1953 {
1954 	struct sk_buff *skb;
1955 
1956 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
1957 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
1958 	    sysctl_optmem_max)
1959 		return NULL;
1960 
1961 	skb = alloc_skb(size, priority);
1962 	if (!skb)
1963 		return NULL;
1964 
1965 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
1966 	skb->sk = sk;
1967 	skb->destructor = sock_ofree;
1968 	return skb;
1969 }
1970 
1971 /*
1972  * Allocate a memory block from the socket's option memory buffer.
1973  */
1974 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1975 {
1976 	if ((unsigned int)size <= sysctl_optmem_max &&
1977 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1978 		void *mem;
1979 		/* First do the add, to avoid the race if kmalloc
1980 		 * might sleep.
1981 		 */
1982 		atomic_add(size, &sk->sk_omem_alloc);
1983 		mem = kmalloc(size, priority);
1984 		if (mem)
1985 			return mem;
1986 		atomic_sub(size, &sk->sk_omem_alloc);
1987 	}
1988 	return NULL;
1989 }
1990 EXPORT_SYMBOL(sock_kmalloc);
1991 
1992 /* Free an option memory block. Note, we actually want the inline
1993  * here as this allows gcc to detect the nullify and fold away the
1994  * condition entirely.
1995  */
1996 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1997 				  const bool nullify)
1998 {
1999 	if (WARN_ON_ONCE(!mem))
2000 		return;
2001 	if (nullify)
2002 		kzfree(mem);
2003 	else
2004 		kfree(mem);
2005 	atomic_sub(size, &sk->sk_omem_alloc);
2006 }
2007 
2008 void sock_kfree_s(struct sock *sk, void *mem, int size)
2009 {
2010 	__sock_kfree_s(sk, mem, size, false);
2011 }
2012 EXPORT_SYMBOL(sock_kfree_s);
2013 
2014 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2015 {
2016 	__sock_kfree_s(sk, mem, size, true);
2017 }
2018 EXPORT_SYMBOL(sock_kzfree_s);
2019 
2020 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2021    I think, these locks should be removed for datagram sockets.
2022  */
2023 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2024 {
2025 	DEFINE_WAIT(wait);
2026 
2027 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2028 	for (;;) {
2029 		if (!timeo)
2030 			break;
2031 		if (signal_pending(current))
2032 			break;
2033 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2034 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2035 		if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2036 			break;
2037 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2038 			break;
2039 		if (sk->sk_err)
2040 			break;
2041 		timeo = schedule_timeout(timeo);
2042 	}
2043 	finish_wait(sk_sleep(sk), &wait);
2044 	return timeo;
2045 }
2046 
2047 
2048 /*
2049  *	Generic send/receive buffer handlers
2050  */
2051 
2052 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2053 				     unsigned long data_len, int noblock,
2054 				     int *errcode, int max_page_order)
2055 {
2056 	struct sk_buff *skb;
2057 	long timeo;
2058 	int err;
2059 
2060 	timeo = sock_sndtimeo(sk, noblock);
2061 	for (;;) {
2062 		err = sock_error(sk);
2063 		if (err != 0)
2064 			goto failure;
2065 
2066 		err = -EPIPE;
2067 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2068 			goto failure;
2069 
2070 		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2071 			break;
2072 
2073 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2074 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2075 		err = -EAGAIN;
2076 		if (!timeo)
2077 			goto failure;
2078 		if (signal_pending(current))
2079 			goto interrupted;
2080 		timeo = sock_wait_for_wmem(sk, timeo);
2081 	}
2082 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2083 				   errcode, sk->sk_allocation);
2084 	if (skb)
2085 		skb_set_owner_w(skb, sk);
2086 	return skb;
2087 
2088 interrupted:
2089 	err = sock_intr_errno(timeo);
2090 failure:
2091 	*errcode = err;
2092 	return NULL;
2093 }
2094 EXPORT_SYMBOL(sock_alloc_send_pskb);
2095 
2096 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2097 				    int noblock, int *errcode)
2098 {
2099 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2100 }
2101 EXPORT_SYMBOL(sock_alloc_send_skb);
2102 
2103 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2104 		     struct sockcm_cookie *sockc)
2105 {
2106 	u32 tsflags;
2107 
2108 	switch (cmsg->cmsg_type) {
2109 	case SO_MARK:
2110 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2111 			return -EPERM;
2112 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2113 			return -EINVAL;
2114 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2115 		break;
2116 	case SO_TIMESTAMPING:
2117 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2118 			return -EINVAL;
2119 
2120 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2121 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2122 			return -EINVAL;
2123 
2124 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2125 		sockc->tsflags |= tsflags;
2126 		break;
2127 	case SCM_TXTIME:
2128 		if (!sock_flag(sk, SOCK_TXTIME))
2129 			return -EINVAL;
2130 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2131 			return -EINVAL;
2132 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2133 		break;
2134 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2135 	case SCM_RIGHTS:
2136 	case SCM_CREDENTIALS:
2137 		break;
2138 	default:
2139 		return -EINVAL;
2140 	}
2141 	return 0;
2142 }
2143 EXPORT_SYMBOL(__sock_cmsg_send);
2144 
2145 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2146 		   struct sockcm_cookie *sockc)
2147 {
2148 	struct cmsghdr *cmsg;
2149 	int ret;
2150 
2151 	for_each_cmsghdr(cmsg, msg) {
2152 		if (!CMSG_OK(msg, cmsg))
2153 			return -EINVAL;
2154 		if (cmsg->cmsg_level != SOL_SOCKET)
2155 			continue;
2156 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2157 		if (ret)
2158 			return ret;
2159 	}
2160 	return 0;
2161 }
2162 EXPORT_SYMBOL(sock_cmsg_send);
2163 
2164 static void sk_enter_memory_pressure(struct sock *sk)
2165 {
2166 	if (!sk->sk_prot->enter_memory_pressure)
2167 		return;
2168 
2169 	sk->sk_prot->enter_memory_pressure(sk);
2170 }
2171 
2172 static void sk_leave_memory_pressure(struct sock *sk)
2173 {
2174 	if (sk->sk_prot->leave_memory_pressure) {
2175 		sk->sk_prot->leave_memory_pressure(sk);
2176 	} else {
2177 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2178 
2179 		if (memory_pressure && *memory_pressure)
2180 			*memory_pressure = 0;
2181 	}
2182 }
2183 
2184 /* On 32bit arches, an skb frag is limited to 2^15 */
2185 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2186 
2187 /**
2188  * skb_page_frag_refill - check that a page_frag contains enough room
2189  * @sz: minimum size of the fragment we want to get
2190  * @pfrag: pointer to page_frag
2191  * @gfp: priority for memory allocation
2192  *
2193  * Note: While this allocator tries to use high order pages, there is
2194  * no guarantee that allocations succeed. Therefore, @sz MUST be
2195  * less or equal than PAGE_SIZE.
2196  */
2197 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2198 {
2199 	if (pfrag->page) {
2200 		if (page_ref_count(pfrag->page) == 1) {
2201 			pfrag->offset = 0;
2202 			return true;
2203 		}
2204 		if (pfrag->offset + sz <= pfrag->size)
2205 			return true;
2206 		put_page(pfrag->page);
2207 	}
2208 
2209 	pfrag->offset = 0;
2210 	if (SKB_FRAG_PAGE_ORDER) {
2211 		/* Avoid direct reclaim but allow kswapd to wake */
2212 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2213 					  __GFP_COMP | __GFP_NOWARN |
2214 					  __GFP_NORETRY,
2215 					  SKB_FRAG_PAGE_ORDER);
2216 		if (likely(pfrag->page)) {
2217 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2218 			return true;
2219 		}
2220 	}
2221 	pfrag->page = alloc_page(gfp);
2222 	if (likely(pfrag->page)) {
2223 		pfrag->size = PAGE_SIZE;
2224 		return true;
2225 	}
2226 	return false;
2227 }
2228 EXPORT_SYMBOL(skb_page_frag_refill);
2229 
2230 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2231 {
2232 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2233 		return true;
2234 
2235 	sk_enter_memory_pressure(sk);
2236 	sk_stream_moderate_sndbuf(sk);
2237 	return false;
2238 }
2239 EXPORT_SYMBOL(sk_page_frag_refill);
2240 
2241 int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2242 		int sg_start, int *sg_curr_index, unsigned int *sg_curr_size,
2243 		int first_coalesce)
2244 {
2245 	int sg_curr = *sg_curr_index, use = 0, rc = 0;
2246 	unsigned int size = *sg_curr_size;
2247 	struct page_frag *pfrag;
2248 	struct scatterlist *sge;
2249 
2250 	len -= size;
2251 	pfrag = sk_page_frag(sk);
2252 
2253 	while (len > 0) {
2254 		unsigned int orig_offset;
2255 
2256 		if (!sk_page_frag_refill(sk, pfrag)) {
2257 			rc = -ENOMEM;
2258 			goto out;
2259 		}
2260 
2261 		use = min_t(int, len, pfrag->size - pfrag->offset);
2262 
2263 		if (!sk_wmem_schedule(sk, use)) {
2264 			rc = -ENOMEM;
2265 			goto out;
2266 		}
2267 
2268 		sk_mem_charge(sk, use);
2269 		size += use;
2270 		orig_offset = pfrag->offset;
2271 		pfrag->offset += use;
2272 
2273 		sge = sg + sg_curr - 1;
2274 		if (sg_curr > first_coalesce && sg_page(sge) == pfrag->page &&
2275 		    sge->offset + sge->length == orig_offset) {
2276 			sge->length += use;
2277 		} else {
2278 			sge = sg + sg_curr;
2279 			sg_unmark_end(sge);
2280 			sg_set_page(sge, pfrag->page, use, orig_offset);
2281 			get_page(pfrag->page);
2282 			sg_curr++;
2283 
2284 			if (sg_curr == MAX_SKB_FRAGS)
2285 				sg_curr = 0;
2286 
2287 			if (sg_curr == sg_start) {
2288 				rc = -ENOSPC;
2289 				break;
2290 			}
2291 		}
2292 
2293 		len -= use;
2294 	}
2295 out:
2296 	*sg_curr_size = size;
2297 	*sg_curr_index = sg_curr;
2298 	return rc;
2299 }
2300 EXPORT_SYMBOL(sk_alloc_sg);
2301 
2302 static void __lock_sock(struct sock *sk)
2303 	__releases(&sk->sk_lock.slock)
2304 	__acquires(&sk->sk_lock.slock)
2305 {
2306 	DEFINE_WAIT(wait);
2307 
2308 	for (;;) {
2309 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2310 					TASK_UNINTERRUPTIBLE);
2311 		spin_unlock_bh(&sk->sk_lock.slock);
2312 		schedule();
2313 		spin_lock_bh(&sk->sk_lock.slock);
2314 		if (!sock_owned_by_user(sk))
2315 			break;
2316 	}
2317 	finish_wait(&sk->sk_lock.wq, &wait);
2318 }
2319 
2320 static void __release_sock(struct sock *sk)
2321 	__releases(&sk->sk_lock.slock)
2322 	__acquires(&sk->sk_lock.slock)
2323 {
2324 	struct sk_buff *skb, *next;
2325 
2326 	while ((skb = sk->sk_backlog.head) != NULL) {
2327 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2328 
2329 		spin_unlock_bh(&sk->sk_lock.slock);
2330 
2331 		do {
2332 			next = skb->next;
2333 			prefetch(next);
2334 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2335 			skb->next = NULL;
2336 			sk_backlog_rcv(sk, skb);
2337 
2338 			cond_resched();
2339 
2340 			skb = next;
2341 		} while (skb != NULL);
2342 
2343 		spin_lock_bh(&sk->sk_lock.slock);
2344 	}
2345 
2346 	/*
2347 	 * Doing the zeroing here guarantee we can not loop forever
2348 	 * while a wild producer attempts to flood us.
2349 	 */
2350 	sk->sk_backlog.len = 0;
2351 }
2352 
2353 void __sk_flush_backlog(struct sock *sk)
2354 {
2355 	spin_lock_bh(&sk->sk_lock.slock);
2356 	__release_sock(sk);
2357 	spin_unlock_bh(&sk->sk_lock.slock);
2358 }
2359 
2360 /**
2361  * sk_wait_data - wait for data to arrive at sk_receive_queue
2362  * @sk:    sock to wait on
2363  * @timeo: for how long
2364  * @skb:   last skb seen on sk_receive_queue
2365  *
2366  * Now socket state including sk->sk_err is changed only under lock,
2367  * hence we may omit checks after joining wait queue.
2368  * We check receive queue before schedule() only as optimization;
2369  * it is very likely that release_sock() added new data.
2370  */
2371 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2372 {
2373 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2374 	int rc;
2375 
2376 	add_wait_queue(sk_sleep(sk), &wait);
2377 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2378 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2379 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2380 	remove_wait_queue(sk_sleep(sk), &wait);
2381 	return rc;
2382 }
2383 EXPORT_SYMBOL(sk_wait_data);
2384 
2385 /**
2386  *	__sk_mem_raise_allocated - increase memory_allocated
2387  *	@sk: socket
2388  *	@size: memory size to allocate
2389  *	@amt: pages to allocate
2390  *	@kind: allocation type
2391  *
2392  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2393  */
2394 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2395 {
2396 	struct proto *prot = sk->sk_prot;
2397 	long allocated = sk_memory_allocated_add(sk, amt);
2398 	bool charged = true;
2399 
2400 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2401 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2402 		goto suppress_allocation;
2403 
2404 	/* Under limit. */
2405 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2406 		sk_leave_memory_pressure(sk);
2407 		return 1;
2408 	}
2409 
2410 	/* Under pressure. */
2411 	if (allocated > sk_prot_mem_limits(sk, 1))
2412 		sk_enter_memory_pressure(sk);
2413 
2414 	/* Over hard limit. */
2415 	if (allocated > sk_prot_mem_limits(sk, 2))
2416 		goto suppress_allocation;
2417 
2418 	/* guarantee minimum buffer size under pressure */
2419 	if (kind == SK_MEM_RECV) {
2420 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2421 			return 1;
2422 
2423 	} else { /* SK_MEM_SEND */
2424 		int wmem0 = sk_get_wmem0(sk, prot);
2425 
2426 		if (sk->sk_type == SOCK_STREAM) {
2427 			if (sk->sk_wmem_queued < wmem0)
2428 				return 1;
2429 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2430 				return 1;
2431 		}
2432 	}
2433 
2434 	if (sk_has_memory_pressure(sk)) {
2435 		int alloc;
2436 
2437 		if (!sk_under_memory_pressure(sk))
2438 			return 1;
2439 		alloc = sk_sockets_allocated_read_positive(sk);
2440 		if (sk_prot_mem_limits(sk, 2) > alloc *
2441 		    sk_mem_pages(sk->sk_wmem_queued +
2442 				 atomic_read(&sk->sk_rmem_alloc) +
2443 				 sk->sk_forward_alloc))
2444 			return 1;
2445 	}
2446 
2447 suppress_allocation:
2448 
2449 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2450 		sk_stream_moderate_sndbuf(sk);
2451 
2452 		/* Fail only if socket is _under_ its sndbuf.
2453 		 * In this case we cannot block, so that we have to fail.
2454 		 */
2455 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2456 			return 1;
2457 	}
2458 
2459 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2460 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2461 
2462 	sk_memory_allocated_sub(sk, amt);
2463 
2464 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2465 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2466 
2467 	return 0;
2468 }
2469 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2470 
2471 /**
2472  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2473  *	@sk: socket
2474  *	@size: memory size to allocate
2475  *	@kind: allocation type
2476  *
2477  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2478  *	rmem allocation. This function assumes that protocols which have
2479  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2480  */
2481 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2482 {
2483 	int ret, amt = sk_mem_pages(size);
2484 
2485 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2486 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2487 	if (!ret)
2488 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2489 	return ret;
2490 }
2491 EXPORT_SYMBOL(__sk_mem_schedule);
2492 
2493 /**
2494  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2495  *	@sk: socket
2496  *	@amount: number of quanta
2497  *
2498  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2499  */
2500 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2501 {
2502 	sk_memory_allocated_sub(sk, amount);
2503 
2504 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2505 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2506 
2507 	if (sk_under_memory_pressure(sk) &&
2508 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2509 		sk_leave_memory_pressure(sk);
2510 }
2511 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2512 
2513 /**
2514  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2515  *	@sk: socket
2516  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2517  */
2518 void __sk_mem_reclaim(struct sock *sk, int amount)
2519 {
2520 	amount >>= SK_MEM_QUANTUM_SHIFT;
2521 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2522 	__sk_mem_reduce_allocated(sk, amount);
2523 }
2524 EXPORT_SYMBOL(__sk_mem_reclaim);
2525 
2526 int sk_set_peek_off(struct sock *sk, int val)
2527 {
2528 	sk->sk_peek_off = val;
2529 	return 0;
2530 }
2531 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2532 
2533 /*
2534  * Set of default routines for initialising struct proto_ops when
2535  * the protocol does not support a particular function. In certain
2536  * cases where it makes no sense for a protocol to have a "do nothing"
2537  * function, some default processing is provided.
2538  */
2539 
2540 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2541 {
2542 	return -EOPNOTSUPP;
2543 }
2544 EXPORT_SYMBOL(sock_no_bind);
2545 
2546 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2547 		    int len, int flags)
2548 {
2549 	return -EOPNOTSUPP;
2550 }
2551 EXPORT_SYMBOL(sock_no_connect);
2552 
2553 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2554 {
2555 	return -EOPNOTSUPP;
2556 }
2557 EXPORT_SYMBOL(sock_no_socketpair);
2558 
2559 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2560 		   bool kern)
2561 {
2562 	return -EOPNOTSUPP;
2563 }
2564 EXPORT_SYMBOL(sock_no_accept);
2565 
2566 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2567 		    int peer)
2568 {
2569 	return -EOPNOTSUPP;
2570 }
2571 EXPORT_SYMBOL(sock_no_getname);
2572 
2573 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2574 {
2575 	return -EOPNOTSUPP;
2576 }
2577 EXPORT_SYMBOL(sock_no_ioctl);
2578 
2579 int sock_no_listen(struct socket *sock, int backlog)
2580 {
2581 	return -EOPNOTSUPP;
2582 }
2583 EXPORT_SYMBOL(sock_no_listen);
2584 
2585 int sock_no_shutdown(struct socket *sock, int how)
2586 {
2587 	return -EOPNOTSUPP;
2588 }
2589 EXPORT_SYMBOL(sock_no_shutdown);
2590 
2591 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2592 		    char __user *optval, unsigned int optlen)
2593 {
2594 	return -EOPNOTSUPP;
2595 }
2596 EXPORT_SYMBOL(sock_no_setsockopt);
2597 
2598 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2599 		    char __user *optval, int __user *optlen)
2600 {
2601 	return -EOPNOTSUPP;
2602 }
2603 EXPORT_SYMBOL(sock_no_getsockopt);
2604 
2605 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2606 {
2607 	return -EOPNOTSUPP;
2608 }
2609 EXPORT_SYMBOL(sock_no_sendmsg);
2610 
2611 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2612 {
2613 	return -EOPNOTSUPP;
2614 }
2615 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2616 
2617 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2618 		    int flags)
2619 {
2620 	return -EOPNOTSUPP;
2621 }
2622 EXPORT_SYMBOL(sock_no_recvmsg);
2623 
2624 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2625 {
2626 	/* Mirror missing mmap method error code */
2627 	return -ENODEV;
2628 }
2629 EXPORT_SYMBOL(sock_no_mmap);
2630 
2631 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2632 {
2633 	ssize_t res;
2634 	struct msghdr msg = {.msg_flags = flags};
2635 	struct kvec iov;
2636 	char *kaddr = kmap(page);
2637 	iov.iov_base = kaddr + offset;
2638 	iov.iov_len = size;
2639 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2640 	kunmap(page);
2641 	return res;
2642 }
2643 EXPORT_SYMBOL(sock_no_sendpage);
2644 
2645 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2646 				int offset, size_t size, int flags)
2647 {
2648 	ssize_t res;
2649 	struct msghdr msg = {.msg_flags = flags};
2650 	struct kvec iov;
2651 	char *kaddr = kmap(page);
2652 
2653 	iov.iov_base = kaddr + offset;
2654 	iov.iov_len = size;
2655 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2656 	kunmap(page);
2657 	return res;
2658 }
2659 EXPORT_SYMBOL(sock_no_sendpage_locked);
2660 
2661 /*
2662  *	Default Socket Callbacks
2663  */
2664 
2665 static void sock_def_wakeup(struct sock *sk)
2666 {
2667 	struct socket_wq *wq;
2668 
2669 	rcu_read_lock();
2670 	wq = rcu_dereference(sk->sk_wq);
2671 	if (skwq_has_sleeper(wq))
2672 		wake_up_interruptible_all(&wq->wait);
2673 	rcu_read_unlock();
2674 }
2675 
2676 static void sock_def_error_report(struct sock *sk)
2677 {
2678 	struct socket_wq *wq;
2679 
2680 	rcu_read_lock();
2681 	wq = rcu_dereference(sk->sk_wq);
2682 	if (skwq_has_sleeper(wq))
2683 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2684 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2685 	rcu_read_unlock();
2686 }
2687 
2688 static void sock_def_readable(struct sock *sk)
2689 {
2690 	struct socket_wq *wq;
2691 
2692 	rcu_read_lock();
2693 	wq = rcu_dereference(sk->sk_wq);
2694 	if (skwq_has_sleeper(wq))
2695 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2696 						EPOLLRDNORM | EPOLLRDBAND);
2697 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2698 	rcu_read_unlock();
2699 }
2700 
2701 static void sock_def_write_space(struct sock *sk)
2702 {
2703 	struct socket_wq *wq;
2704 
2705 	rcu_read_lock();
2706 
2707 	/* Do not wake up a writer until he can make "significant"
2708 	 * progress.  --DaveM
2709 	 */
2710 	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2711 		wq = rcu_dereference(sk->sk_wq);
2712 		if (skwq_has_sleeper(wq))
2713 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2714 						EPOLLWRNORM | EPOLLWRBAND);
2715 
2716 		/* Should agree with poll, otherwise some programs break */
2717 		if (sock_writeable(sk))
2718 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2719 	}
2720 
2721 	rcu_read_unlock();
2722 }
2723 
2724 static void sock_def_destruct(struct sock *sk)
2725 {
2726 }
2727 
2728 void sk_send_sigurg(struct sock *sk)
2729 {
2730 	if (sk->sk_socket && sk->sk_socket->file)
2731 		if (send_sigurg(&sk->sk_socket->file->f_owner))
2732 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2733 }
2734 EXPORT_SYMBOL(sk_send_sigurg);
2735 
2736 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2737 		    unsigned long expires)
2738 {
2739 	if (!mod_timer(timer, expires))
2740 		sock_hold(sk);
2741 }
2742 EXPORT_SYMBOL(sk_reset_timer);
2743 
2744 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2745 {
2746 	if (del_timer(timer))
2747 		__sock_put(sk);
2748 }
2749 EXPORT_SYMBOL(sk_stop_timer);
2750 
2751 void sock_init_data(struct socket *sock, struct sock *sk)
2752 {
2753 	sk_init_common(sk);
2754 	sk->sk_send_head	=	NULL;
2755 
2756 	timer_setup(&sk->sk_timer, NULL, 0);
2757 
2758 	sk->sk_allocation	=	GFP_KERNEL;
2759 	sk->sk_rcvbuf		=	sysctl_rmem_default;
2760 	sk->sk_sndbuf		=	sysctl_wmem_default;
2761 	sk->sk_state		=	TCP_CLOSE;
2762 	sk_set_socket(sk, sock);
2763 
2764 	sock_set_flag(sk, SOCK_ZAPPED);
2765 
2766 	if (sock) {
2767 		sk->sk_type	=	sock->type;
2768 		sk->sk_wq	=	sock->wq;
2769 		sock->sk	=	sk;
2770 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2771 	} else {
2772 		sk->sk_wq	=	NULL;
2773 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2774 	}
2775 
2776 	rwlock_init(&sk->sk_callback_lock);
2777 	if (sk->sk_kern_sock)
2778 		lockdep_set_class_and_name(
2779 			&sk->sk_callback_lock,
2780 			af_kern_callback_keys + sk->sk_family,
2781 			af_family_kern_clock_key_strings[sk->sk_family]);
2782 	else
2783 		lockdep_set_class_and_name(
2784 			&sk->sk_callback_lock,
2785 			af_callback_keys + sk->sk_family,
2786 			af_family_clock_key_strings[sk->sk_family]);
2787 
2788 	sk->sk_state_change	=	sock_def_wakeup;
2789 	sk->sk_data_ready	=	sock_def_readable;
2790 	sk->sk_write_space	=	sock_def_write_space;
2791 	sk->sk_error_report	=	sock_def_error_report;
2792 	sk->sk_destruct		=	sock_def_destruct;
2793 
2794 	sk->sk_frag.page	=	NULL;
2795 	sk->sk_frag.offset	=	0;
2796 	sk->sk_peek_off		=	-1;
2797 
2798 	sk->sk_peer_pid 	=	NULL;
2799 	sk->sk_peer_cred	=	NULL;
2800 	sk->sk_write_pending	=	0;
2801 	sk->sk_rcvlowat		=	1;
2802 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2803 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2804 
2805 	sk->sk_stamp = SK_DEFAULT_STAMP;
2806 	atomic_set(&sk->sk_zckey, 0);
2807 
2808 #ifdef CONFIG_NET_RX_BUSY_POLL
2809 	sk->sk_napi_id		=	0;
2810 	sk->sk_ll_usec		=	sysctl_net_busy_read;
2811 #endif
2812 
2813 	sk->sk_max_pacing_rate = ~0U;
2814 	sk->sk_pacing_rate = ~0U;
2815 	sk->sk_pacing_shift = 10;
2816 	sk->sk_incoming_cpu = -1;
2817 
2818 	sk_rx_queue_clear(sk);
2819 	/*
2820 	 * Before updating sk_refcnt, we must commit prior changes to memory
2821 	 * (Documentation/RCU/rculist_nulls.txt for details)
2822 	 */
2823 	smp_wmb();
2824 	refcount_set(&sk->sk_refcnt, 1);
2825 	atomic_set(&sk->sk_drops, 0);
2826 }
2827 EXPORT_SYMBOL(sock_init_data);
2828 
2829 void lock_sock_nested(struct sock *sk, int subclass)
2830 {
2831 	might_sleep();
2832 	spin_lock_bh(&sk->sk_lock.slock);
2833 	if (sk->sk_lock.owned)
2834 		__lock_sock(sk);
2835 	sk->sk_lock.owned = 1;
2836 	spin_unlock(&sk->sk_lock.slock);
2837 	/*
2838 	 * The sk_lock has mutex_lock() semantics here:
2839 	 */
2840 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2841 	local_bh_enable();
2842 }
2843 EXPORT_SYMBOL(lock_sock_nested);
2844 
2845 void release_sock(struct sock *sk)
2846 {
2847 	spin_lock_bh(&sk->sk_lock.slock);
2848 	if (sk->sk_backlog.tail)
2849 		__release_sock(sk);
2850 
2851 	/* Warning : release_cb() might need to release sk ownership,
2852 	 * ie call sock_release_ownership(sk) before us.
2853 	 */
2854 	if (sk->sk_prot->release_cb)
2855 		sk->sk_prot->release_cb(sk);
2856 
2857 	sock_release_ownership(sk);
2858 	if (waitqueue_active(&sk->sk_lock.wq))
2859 		wake_up(&sk->sk_lock.wq);
2860 	spin_unlock_bh(&sk->sk_lock.slock);
2861 }
2862 EXPORT_SYMBOL(release_sock);
2863 
2864 /**
2865  * lock_sock_fast - fast version of lock_sock
2866  * @sk: socket
2867  *
2868  * This version should be used for very small section, where process wont block
2869  * return false if fast path is taken:
2870  *
2871  *   sk_lock.slock locked, owned = 0, BH disabled
2872  *
2873  * return true if slow path is taken:
2874  *
2875  *   sk_lock.slock unlocked, owned = 1, BH enabled
2876  */
2877 bool lock_sock_fast(struct sock *sk)
2878 {
2879 	might_sleep();
2880 	spin_lock_bh(&sk->sk_lock.slock);
2881 
2882 	if (!sk->sk_lock.owned)
2883 		/*
2884 		 * Note : We must disable BH
2885 		 */
2886 		return false;
2887 
2888 	__lock_sock(sk);
2889 	sk->sk_lock.owned = 1;
2890 	spin_unlock(&sk->sk_lock.slock);
2891 	/*
2892 	 * The sk_lock has mutex_lock() semantics here:
2893 	 */
2894 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2895 	local_bh_enable();
2896 	return true;
2897 }
2898 EXPORT_SYMBOL(lock_sock_fast);
2899 
2900 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2901 {
2902 	struct timeval tv;
2903 
2904 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2905 	tv = ktime_to_timeval(sk->sk_stamp);
2906 	if (tv.tv_sec == -1)
2907 		return -ENOENT;
2908 	if (tv.tv_sec == 0) {
2909 		sk->sk_stamp = ktime_get_real();
2910 		tv = ktime_to_timeval(sk->sk_stamp);
2911 	}
2912 	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2913 }
2914 EXPORT_SYMBOL(sock_get_timestamp);
2915 
2916 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2917 {
2918 	struct timespec ts;
2919 
2920 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2921 	ts = ktime_to_timespec(sk->sk_stamp);
2922 	if (ts.tv_sec == -1)
2923 		return -ENOENT;
2924 	if (ts.tv_sec == 0) {
2925 		sk->sk_stamp = ktime_get_real();
2926 		ts = ktime_to_timespec(sk->sk_stamp);
2927 	}
2928 	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2929 }
2930 EXPORT_SYMBOL(sock_get_timestampns);
2931 
2932 void sock_enable_timestamp(struct sock *sk, int flag)
2933 {
2934 	if (!sock_flag(sk, flag)) {
2935 		unsigned long previous_flags = sk->sk_flags;
2936 
2937 		sock_set_flag(sk, flag);
2938 		/*
2939 		 * we just set one of the two flags which require net
2940 		 * time stamping, but time stamping might have been on
2941 		 * already because of the other one
2942 		 */
2943 		if (sock_needs_netstamp(sk) &&
2944 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
2945 			net_enable_timestamp();
2946 	}
2947 }
2948 
2949 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2950 		       int level, int type)
2951 {
2952 	struct sock_exterr_skb *serr;
2953 	struct sk_buff *skb;
2954 	int copied, err;
2955 
2956 	err = -EAGAIN;
2957 	skb = sock_dequeue_err_skb(sk);
2958 	if (skb == NULL)
2959 		goto out;
2960 
2961 	copied = skb->len;
2962 	if (copied > len) {
2963 		msg->msg_flags |= MSG_TRUNC;
2964 		copied = len;
2965 	}
2966 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
2967 	if (err)
2968 		goto out_free_skb;
2969 
2970 	sock_recv_timestamp(msg, sk, skb);
2971 
2972 	serr = SKB_EXT_ERR(skb);
2973 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2974 
2975 	msg->msg_flags |= MSG_ERRQUEUE;
2976 	err = copied;
2977 
2978 out_free_skb:
2979 	kfree_skb(skb);
2980 out:
2981 	return err;
2982 }
2983 EXPORT_SYMBOL(sock_recv_errqueue);
2984 
2985 /*
2986  *	Get a socket option on an socket.
2987  *
2988  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2989  *	asynchronous errors should be reported by getsockopt. We assume
2990  *	this means if you specify SO_ERROR (otherwise whats the point of it).
2991  */
2992 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2993 			   char __user *optval, int __user *optlen)
2994 {
2995 	struct sock *sk = sock->sk;
2996 
2997 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2998 }
2999 EXPORT_SYMBOL(sock_common_getsockopt);
3000 
3001 #ifdef CONFIG_COMPAT
3002 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
3003 				  char __user *optval, int __user *optlen)
3004 {
3005 	struct sock *sk = sock->sk;
3006 
3007 	if (sk->sk_prot->compat_getsockopt != NULL)
3008 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
3009 						      optval, optlen);
3010 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3011 }
3012 EXPORT_SYMBOL(compat_sock_common_getsockopt);
3013 #endif
3014 
3015 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3016 			int flags)
3017 {
3018 	struct sock *sk = sock->sk;
3019 	int addr_len = 0;
3020 	int err;
3021 
3022 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3023 				   flags & ~MSG_DONTWAIT, &addr_len);
3024 	if (err >= 0)
3025 		msg->msg_namelen = addr_len;
3026 	return err;
3027 }
3028 EXPORT_SYMBOL(sock_common_recvmsg);
3029 
3030 /*
3031  *	Set socket options on an inet socket.
3032  */
3033 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3034 			   char __user *optval, unsigned int optlen)
3035 {
3036 	struct sock *sk = sock->sk;
3037 
3038 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3039 }
3040 EXPORT_SYMBOL(sock_common_setsockopt);
3041 
3042 #ifdef CONFIG_COMPAT
3043 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
3044 				  char __user *optval, unsigned int optlen)
3045 {
3046 	struct sock *sk = sock->sk;
3047 
3048 	if (sk->sk_prot->compat_setsockopt != NULL)
3049 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
3050 						      optval, optlen);
3051 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3052 }
3053 EXPORT_SYMBOL(compat_sock_common_setsockopt);
3054 #endif
3055 
3056 void sk_common_release(struct sock *sk)
3057 {
3058 	if (sk->sk_prot->destroy)
3059 		sk->sk_prot->destroy(sk);
3060 
3061 	/*
3062 	 * Observation: when sock_common_release is called, processes have
3063 	 * no access to socket. But net still has.
3064 	 * Step one, detach it from networking:
3065 	 *
3066 	 * A. Remove from hash tables.
3067 	 */
3068 
3069 	sk->sk_prot->unhash(sk);
3070 
3071 	/*
3072 	 * In this point socket cannot receive new packets, but it is possible
3073 	 * that some packets are in flight because some CPU runs receiver and
3074 	 * did hash table lookup before we unhashed socket. They will achieve
3075 	 * receive queue and will be purged by socket destructor.
3076 	 *
3077 	 * Also we still have packets pending on receive queue and probably,
3078 	 * our own packets waiting in device queues. sock_destroy will drain
3079 	 * receive queue, but transmitted packets will delay socket destruction
3080 	 * until the last reference will be released.
3081 	 */
3082 
3083 	sock_orphan(sk);
3084 
3085 	xfrm_sk_free_policy(sk);
3086 
3087 	sk_refcnt_debug_release(sk);
3088 
3089 	sock_put(sk);
3090 }
3091 EXPORT_SYMBOL(sk_common_release);
3092 
3093 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3094 {
3095 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3096 
3097 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3098 	mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3099 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3100 	mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3101 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3102 	mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3103 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3104 	mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3105 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3106 }
3107 
3108 #ifdef CONFIG_PROC_FS
3109 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
3110 struct prot_inuse {
3111 	int val[PROTO_INUSE_NR];
3112 };
3113 
3114 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3115 
3116 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3117 {
3118 	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3119 }
3120 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3121 
3122 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3123 {
3124 	int cpu, idx = prot->inuse_idx;
3125 	int res = 0;
3126 
3127 	for_each_possible_cpu(cpu)
3128 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3129 
3130 	return res >= 0 ? res : 0;
3131 }
3132 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3133 
3134 static void sock_inuse_add(struct net *net, int val)
3135 {
3136 	this_cpu_add(*net->core.sock_inuse, val);
3137 }
3138 
3139 int sock_inuse_get(struct net *net)
3140 {
3141 	int cpu, res = 0;
3142 
3143 	for_each_possible_cpu(cpu)
3144 		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3145 
3146 	return res;
3147 }
3148 
3149 EXPORT_SYMBOL_GPL(sock_inuse_get);
3150 
3151 static int __net_init sock_inuse_init_net(struct net *net)
3152 {
3153 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3154 	if (net->core.prot_inuse == NULL)
3155 		return -ENOMEM;
3156 
3157 	net->core.sock_inuse = alloc_percpu(int);
3158 	if (net->core.sock_inuse == NULL)
3159 		goto out;
3160 
3161 	return 0;
3162 
3163 out:
3164 	free_percpu(net->core.prot_inuse);
3165 	return -ENOMEM;
3166 }
3167 
3168 static void __net_exit sock_inuse_exit_net(struct net *net)
3169 {
3170 	free_percpu(net->core.prot_inuse);
3171 	free_percpu(net->core.sock_inuse);
3172 }
3173 
3174 static struct pernet_operations net_inuse_ops = {
3175 	.init = sock_inuse_init_net,
3176 	.exit = sock_inuse_exit_net,
3177 };
3178 
3179 static __init int net_inuse_init(void)
3180 {
3181 	if (register_pernet_subsys(&net_inuse_ops))
3182 		panic("Cannot initialize net inuse counters");
3183 
3184 	return 0;
3185 }
3186 
3187 core_initcall(net_inuse_init);
3188 
3189 static void assign_proto_idx(struct proto *prot)
3190 {
3191 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3192 
3193 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3194 		pr_err("PROTO_INUSE_NR exhausted\n");
3195 		return;
3196 	}
3197 
3198 	set_bit(prot->inuse_idx, proto_inuse_idx);
3199 }
3200 
3201 static void release_proto_idx(struct proto *prot)
3202 {
3203 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3204 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3205 }
3206 #else
3207 static inline void assign_proto_idx(struct proto *prot)
3208 {
3209 }
3210 
3211 static inline void release_proto_idx(struct proto *prot)
3212 {
3213 }
3214 
3215 static void sock_inuse_add(struct net *net, int val)
3216 {
3217 }
3218 #endif
3219 
3220 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3221 {
3222 	if (!rsk_prot)
3223 		return;
3224 	kfree(rsk_prot->slab_name);
3225 	rsk_prot->slab_name = NULL;
3226 	kmem_cache_destroy(rsk_prot->slab);
3227 	rsk_prot->slab = NULL;
3228 }
3229 
3230 static int req_prot_init(const struct proto *prot)
3231 {
3232 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3233 
3234 	if (!rsk_prot)
3235 		return 0;
3236 
3237 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3238 					prot->name);
3239 	if (!rsk_prot->slab_name)
3240 		return -ENOMEM;
3241 
3242 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3243 					   rsk_prot->obj_size, 0,
3244 					   SLAB_ACCOUNT | prot->slab_flags,
3245 					   NULL);
3246 
3247 	if (!rsk_prot->slab) {
3248 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3249 			prot->name);
3250 		return -ENOMEM;
3251 	}
3252 	return 0;
3253 }
3254 
3255 int proto_register(struct proto *prot, int alloc_slab)
3256 {
3257 	if (alloc_slab) {
3258 		prot->slab = kmem_cache_create_usercopy(prot->name,
3259 					prot->obj_size, 0,
3260 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3261 					prot->slab_flags,
3262 					prot->useroffset, prot->usersize,
3263 					NULL);
3264 
3265 		if (prot->slab == NULL) {
3266 			pr_crit("%s: Can't create sock SLAB cache!\n",
3267 				prot->name);
3268 			goto out;
3269 		}
3270 
3271 		if (req_prot_init(prot))
3272 			goto out_free_request_sock_slab;
3273 
3274 		if (prot->twsk_prot != NULL) {
3275 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3276 
3277 			if (prot->twsk_prot->twsk_slab_name == NULL)
3278 				goto out_free_request_sock_slab;
3279 
3280 			prot->twsk_prot->twsk_slab =
3281 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3282 						  prot->twsk_prot->twsk_obj_size,
3283 						  0,
3284 						  SLAB_ACCOUNT |
3285 						  prot->slab_flags,
3286 						  NULL);
3287 			if (prot->twsk_prot->twsk_slab == NULL)
3288 				goto out_free_timewait_sock_slab_name;
3289 		}
3290 	}
3291 
3292 	mutex_lock(&proto_list_mutex);
3293 	list_add(&prot->node, &proto_list);
3294 	assign_proto_idx(prot);
3295 	mutex_unlock(&proto_list_mutex);
3296 	return 0;
3297 
3298 out_free_timewait_sock_slab_name:
3299 	kfree(prot->twsk_prot->twsk_slab_name);
3300 out_free_request_sock_slab:
3301 	req_prot_cleanup(prot->rsk_prot);
3302 
3303 	kmem_cache_destroy(prot->slab);
3304 	prot->slab = NULL;
3305 out:
3306 	return -ENOBUFS;
3307 }
3308 EXPORT_SYMBOL(proto_register);
3309 
3310 void proto_unregister(struct proto *prot)
3311 {
3312 	mutex_lock(&proto_list_mutex);
3313 	release_proto_idx(prot);
3314 	list_del(&prot->node);
3315 	mutex_unlock(&proto_list_mutex);
3316 
3317 	kmem_cache_destroy(prot->slab);
3318 	prot->slab = NULL;
3319 
3320 	req_prot_cleanup(prot->rsk_prot);
3321 
3322 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3323 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3324 		kfree(prot->twsk_prot->twsk_slab_name);
3325 		prot->twsk_prot->twsk_slab = NULL;
3326 	}
3327 }
3328 EXPORT_SYMBOL(proto_unregister);
3329 
3330 int sock_load_diag_module(int family, int protocol)
3331 {
3332 	if (!protocol) {
3333 		if (!sock_is_registered(family))
3334 			return -ENOENT;
3335 
3336 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3337 				      NETLINK_SOCK_DIAG, family);
3338 	}
3339 
3340 #ifdef CONFIG_INET
3341 	if (family == AF_INET &&
3342 	    !rcu_access_pointer(inet_protos[protocol]))
3343 		return -ENOENT;
3344 #endif
3345 
3346 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3347 			      NETLINK_SOCK_DIAG, family, protocol);
3348 }
3349 EXPORT_SYMBOL(sock_load_diag_module);
3350 
3351 #ifdef CONFIG_PROC_FS
3352 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3353 	__acquires(proto_list_mutex)
3354 {
3355 	mutex_lock(&proto_list_mutex);
3356 	return seq_list_start_head(&proto_list, *pos);
3357 }
3358 
3359 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3360 {
3361 	return seq_list_next(v, &proto_list, pos);
3362 }
3363 
3364 static void proto_seq_stop(struct seq_file *seq, void *v)
3365 	__releases(proto_list_mutex)
3366 {
3367 	mutex_unlock(&proto_list_mutex);
3368 }
3369 
3370 static char proto_method_implemented(const void *method)
3371 {
3372 	return method == NULL ? 'n' : 'y';
3373 }
3374 static long sock_prot_memory_allocated(struct proto *proto)
3375 {
3376 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3377 }
3378 
3379 static char *sock_prot_memory_pressure(struct proto *proto)
3380 {
3381 	return proto->memory_pressure != NULL ?
3382 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3383 }
3384 
3385 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3386 {
3387 
3388 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3389 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3390 		   proto->name,
3391 		   proto->obj_size,
3392 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3393 		   sock_prot_memory_allocated(proto),
3394 		   sock_prot_memory_pressure(proto),
3395 		   proto->max_header,
3396 		   proto->slab == NULL ? "no" : "yes",
3397 		   module_name(proto->owner),
3398 		   proto_method_implemented(proto->close),
3399 		   proto_method_implemented(proto->connect),
3400 		   proto_method_implemented(proto->disconnect),
3401 		   proto_method_implemented(proto->accept),
3402 		   proto_method_implemented(proto->ioctl),
3403 		   proto_method_implemented(proto->init),
3404 		   proto_method_implemented(proto->destroy),
3405 		   proto_method_implemented(proto->shutdown),
3406 		   proto_method_implemented(proto->setsockopt),
3407 		   proto_method_implemented(proto->getsockopt),
3408 		   proto_method_implemented(proto->sendmsg),
3409 		   proto_method_implemented(proto->recvmsg),
3410 		   proto_method_implemented(proto->sendpage),
3411 		   proto_method_implemented(proto->bind),
3412 		   proto_method_implemented(proto->backlog_rcv),
3413 		   proto_method_implemented(proto->hash),
3414 		   proto_method_implemented(proto->unhash),
3415 		   proto_method_implemented(proto->get_port),
3416 		   proto_method_implemented(proto->enter_memory_pressure));
3417 }
3418 
3419 static int proto_seq_show(struct seq_file *seq, void *v)
3420 {
3421 	if (v == &proto_list)
3422 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3423 			   "protocol",
3424 			   "size",
3425 			   "sockets",
3426 			   "memory",
3427 			   "press",
3428 			   "maxhdr",
3429 			   "slab",
3430 			   "module",
3431 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3432 	else
3433 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3434 	return 0;
3435 }
3436 
3437 static const struct seq_operations proto_seq_ops = {
3438 	.start  = proto_seq_start,
3439 	.next   = proto_seq_next,
3440 	.stop   = proto_seq_stop,
3441 	.show   = proto_seq_show,
3442 };
3443 
3444 static __net_init int proto_init_net(struct net *net)
3445 {
3446 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3447 			sizeof(struct seq_net_private)))
3448 		return -ENOMEM;
3449 
3450 	return 0;
3451 }
3452 
3453 static __net_exit void proto_exit_net(struct net *net)
3454 {
3455 	remove_proc_entry("protocols", net->proc_net);
3456 }
3457 
3458 
3459 static __net_initdata struct pernet_operations proto_net_ops = {
3460 	.init = proto_init_net,
3461 	.exit = proto_exit_net,
3462 };
3463 
3464 static int __init proto_init(void)
3465 {
3466 	return register_pernet_subsys(&proto_net_ops);
3467 }
3468 
3469 subsys_initcall(proto_init);
3470 
3471 #endif /* PROC_FS */
3472 
3473 #ifdef CONFIG_NET_RX_BUSY_POLL
3474 bool sk_busy_loop_end(void *p, unsigned long start_time)
3475 {
3476 	struct sock *sk = p;
3477 
3478 	return !skb_queue_empty(&sk->sk_receive_queue) ||
3479 	       sk_busy_loop_timeout(sk, start_time);
3480 }
3481 EXPORT_SYMBOL(sk_busy_loop_end);
3482 #endif /* CONFIG_NET_RX_BUSY_POLL */
3483