xref: /linux/net/core/sock.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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 #include <linux/capability.h>
93 #include <linux/errno.h>
94 #include <linux/types.h>
95 #include <linux/socket.h>
96 #include <linux/in.h>
97 #include <linux/kernel.h>
98 #include <linux/module.h>
99 #include <linux/proc_fs.h>
100 #include <linux/seq_file.h>
101 #include <linux/sched.h>
102 #include <linux/timer.h>
103 #include <linux/string.h>
104 #include <linux/sockios.h>
105 #include <linux/net.h>
106 #include <linux/mm.h>
107 #include <linux/slab.h>
108 #include <linux/interrupt.h>
109 #include <linux/poll.h>
110 #include <linux/tcp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 
115 #include <asm/uaccess.h>
116 #include <asm/system.h>
117 
118 #include <linux/netdevice.h>
119 #include <net/protocol.h>
120 #include <linux/skbuff.h>
121 #include <net/net_namespace.h>
122 #include <net/request_sock.h>
123 #include <net/sock.h>
124 #include <linux/net_tstamp.h>
125 #include <net/xfrm.h>
126 #include <linux/ipsec.h>
127 #include <net/cls_cgroup.h>
128 
129 #include <linux/filter.h>
130 
131 #include <trace/events/sock.h>
132 
133 #ifdef CONFIG_INET
134 #include <net/tcp.h>
135 #endif
136 
137 /*
138  * Each address family might have different locking rules, so we have
139  * one slock key per address family:
140  */
141 static struct lock_class_key af_family_keys[AF_MAX];
142 static struct lock_class_key af_family_slock_keys[AF_MAX];
143 
144 /*
145  * Make lock validator output more readable. (we pre-construct these
146  * strings build-time, so that runtime initialization of socket
147  * locks is fast):
148  */
149 static const char *const af_family_key_strings[AF_MAX+1] = {
150   "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
151   "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
152   "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
153   "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
154   "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
155   "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
156   "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
157   "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
158   "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
159   "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
160   "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
161   "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
162   "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
163   "sk_lock-AF_NFC"   , "sk_lock-AF_MAX"
164 };
165 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
166   "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
167   "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
168   "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
169   "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
170   "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
171   "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
172   "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
173   "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
174   "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
175   "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
176   "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
177   "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
178   "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
179   "slock-AF_NFC"   , "slock-AF_MAX"
180 };
181 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
182   "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
183   "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
184   "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
185   "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
186   "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
187   "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
188   "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
189   "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
190   "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
191   "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
192   "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
193   "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
194   "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
195   "clock-AF_NFC"   , "clock-AF_MAX"
196 };
197 
198 /*
199  * sk_callback_lock locking rules are per-address-family,
200  * so split the lock classes by using a per-AF key:
201  */
202 static struct lock_class_key af_callback_keys[AF_MAX];
203 
204 /* Take into consideration the size of the struct sk_buff overhead in the
205  * determination of these values, since that is non-constant across
206  * platforms.  This makes socket queueing behavior and performance
207  * not depend upon such differences.
208  */
209 #define _SK_MEM_PACKETS		256
210 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
211 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
212 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
213 
214 /* Run time adjustable parameters. */
215 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
216 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
217 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
218 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
219 
220 /* Maximal space eaten by iovec or ancillary data plus some space */
221 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
222 EXPORT_SYMBOL(sysctl_optmem_max);
223 
224 #if defined(CONFIG_CGROUPS) && !defined(CONFIG_NET_CLS_CGROUP)
225 int net_cls_subsys_id = -1;
226 EXPORT_SYMBOL_GPL(net_cls_subsys_id);
227 #endif
228 
229 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
230 {
231 	struct timeval tv;
232 
233 	if (optlen < sizeof(tv))
234 		return -EINVAL;
235 	if (copy_from_user(&tv, optval, sizeof(tv)))
236 		return -EFAULT;
237 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
238 		return -EDOM;
239 
240 	if (tv.tv_sec < 0) {
241 		static int warned __read_mostly;
242 
243 		*timeo_p = 0;
244 		if (warned < 10 && net_ratelimit()) {
245 			warned++;
246 			printk(KERN_INFO "sock_set_timeout: `%s' (pid %d) "
247 			       "tries to set negative timeout\n",
248 				current->comm, task_pid_nr(current));
249 		}
250 		return 0;
251 	}
252 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
253 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
254 		return 0;
255 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
256 		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
257 	return 0;
258 }
259 
260 static void sock_warn_obsolete_bsdism(const char *name)
261 {
262 	static int warned;
263 	static char warncomm[TASK_COMM_LEN];
264 	if (strcmp(warncomm, current->comm) && warned < 5) {
265 		strcpy(warncomm,  current->comm);
266 		printk(KERN_WARNING "process `%s' is using obsolete "
267 		       "%s SO_BSDCOMPAT\n", warncomm, name);
268 		warned++;
269 	}
270 }
271 
272 static void sock_disable_timestamp(struct sock *sk, int flag)
273 {
274 	if (sock_flag(sk, flag)) {
275 		sock_reset_flag(sk, flag);
276 		if (!sock_flag(sk, SOCK_TIMESTAMP) &&
277 		    !sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) {
278 			net_disable_timestamp();
279 		}
280 	}
281 }
282 
283 
284 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
285 {
286 	int err;
287 	int skb_len;
288 	unsigned long flags;
289 	struct sk_buff_head *list = &sk->sk_receive_queue;
290 
291 	/* Cast sk->rcvbuf to unsigned... It's pointless, but reduces
292 	   number of warnings when compiling with -W --ANK
293 	 */
294 	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
295 	    (unsigned)sk->sk_rcvbuf) {
296 		atomic_inc(&sk->sk_drops);
297 		trace_sock_rcvqueue_full(sk, skb);
298 		return -ENOMEM;
299 	}
300 
301 	err = sk_filter(sk, skb);
302 	if (err)
303 		return err;
304 
305 	if (!sk_rmem_schedule(sk, skb->truesize)) {
306 		atomic_inc(&sk->sk_drops);
307 		return -ENOBUFS;
308 	}
309 
310 	skb->dev = NULL;
311 	skb_set_owner_r(skb, sk);
312 
313 	/* Cache the SKB length before we tack it onto the receive
314 	 * queue.  Once it is added it no longer belongs to us and
315 	 * may be freed by other threads of control pulling packets
316 	 * from the queue.
317 	 */
318 	skb_len = skb->len;
319 
320 	/* we escape from rcu protected region, make sure we dont leak
321 	 * a norefcounted dst
322 	 */
323 	skb_dst_force(skb);
324 
325 	spin_lock_irqsave(&list->lock, flags);
326 	skb->dropcount = atomic_read(&sk->sk_drops);
327 	__skb_queue_tail(list, skb);
328 	spin_unlock_irqrestore(&list->lock, flags);
329 
330 	if (!sock_flag(sk, SOCK_DEAD))
331 		sk->sk_data_ready(sk, skb_len);
332 	return 0;
333 }
334 EXPORT_SYMBOL(sock_queue_rcv_skb);
335 
336 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
337 {
338 	int rc = NET_RX_SUCCESS;
339 
340 	if (sk_filter(sk, skb))
341 		goto discard_and_relse;
342 
343 	skb->dev = NULL;
344 
345 	if (sk_rcvqueues_full(sk, skb)) {
346 		atomic_inc(&sk->sk_drops);
347 		goto discard_and_relse;
348 	}
349 	if (nested)
350 		bh_lock_sock_nested(sk);
351 	else
352 		bh_lock_sock(sk);
353 	if (!sock_owned_by_user(sk)) {
354 		/*
355 		 * trylock + unlock semantics:
356 		 */
357 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
358 
359 		rc = sk_backlog_rcv(sk, skb);
360 
361 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
362 	} else if (sk_add_backlog(sk, skb)) {
363 		bh_unlock_sock(sk);
364 		atomic_inc(&sk->sk_drops);
365 		goto discard_and_relse;
366 	}
367 
368 	bh_unlock_sock(sk);
369 out:
370 	sock_put(sk);
371 	return rc;
372 discard_and_relse:
373 	kfree_skb(skb);
374 	goto out;
375 }
376 EXPORT_SYMBOL(sk_receive_skb);
377 
378 void sk_reset_txq(struct sock *sk)
379 {
380 	sk_tx_queue_clear(sk);
381 }
382 EXPORT_SYMBOL(sk_reset_txq);
383 
384 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
385 {
386 	struct dst_entry *dst = __sk_dst_get(sk);
387 
388 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
389 		sk_tx_queue_clear(sk);
390 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
391 		dst_release(dst);
392 		return NULL;
393 	}
394 
395 	return dst;
396 }
397 EXPORT_SYMBOL(__sk_dst_check);
398 
399 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
400 {
401 	struct dst_entry *dst = sk_dst_get(sk);
402 
403 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
404 		sk_dst_reset(sk);
405 		dst_release(dst);
406 		return NULL;
407 	}
408 
409 	return dst;
410 }
411 EXPORT_SYMBOL(sk_dst_check);
412 
413 static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
414 {
415 	int ret = -ENOPROTOOPT;
416 #ifdef CONFIG_NETDEVICES
417 	struct net *net = sock_net(sk);
418 	char devname[IFNAMSIZ];
419 	int index;
420 
421 	/* Sorry... */
422 	ret = -EPERM;
423 	if (!capable(CAP_NET_RAW))
424 		goto out;
425 
426 	ret = -EINVAL;
427 	if (optlen < 0)
428 		goto out;
429 
430 	/* Bind this socket to a particular device like "eth0",
431 	 * as specified in the passed interface name. If the
432 	 * name is "" or the option length is zero the socket
433 	 * is not bound.
434 	 */
435 	if (optlen > IFNAMSIZ - 1)
436 		optlen = IFNAMSIZ - 1;
437 	memset(devname, 0, sizeof(devname));
438 
439 	ret = -EFAULT;
440 	if (copy_from_user(devname, optval, optlen))
441 		goto out;
442 
443 	index = 0;
444 	if (devname[0] != '\0') {
445 		struct net_device *dev;
446 
447 		rcu_read_lock();
448 		dev = dev_get_by_name_rcu(net, devname);
449 		if (dev)
450 			index = dev->ifindex;
451 		rcu_read_unlock();
452 		ret = -ENODEV;
453 		if (!dev)
454 			goto out;
455 	}
456 
457 	lock_sock(sk);
458 	sk->sk_bound_dev_if = index;
459 	sk_dst_reset(sk);
460 	release_sock(sk);
461 
462 	ret = 0;
463 
464 out:
465 #endif
466 
467 	return ret;
468 }
469 
470 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
471 {
472 	if (valbool)
473 		sock_set_flag(sk, bit);
474 	else
475 		sock_reset_flag(sk, bit);
476 }
477 
478 /*
479  *	This is meant for all protocols to use and covers goings on
480  *	at the socket level. Everything here is generic.
481  */
482 
483 int sock_setsockopt(struct socket *sock, int level, int optname,
484 		    char __user *optval, unsigned int optlen)
485 {
486 	struct sock *sk = sock->sk;
487 	int val;
488 	int valbool;
489 	struct linger ling;
490 	int ret = 0;
491 
492 	/*
493 	 *	Options without arguments
494 	 */
495 
496 	if (optname == SO_BINDTODEVICE)
497 		return sock_bindtodevice(sk, optval, optlen);
498 
499 	if (optlen < sizeof(int))
500 		return -EINVAL;
501 
502 	if (get_user(val, (int __user *)optval))
503 		return -EFAULT;
504 
505 	valbool = val ? 1 : 0;
506 
507 	lock_sock(sk);
508 
509 	switch (optname) {
510 	case SO_DEBUG:
511 		if (val && !capable(CAP_NET_ADMIN))
512 			ret = -EACCES;
513 		else
514 			sock_valbool_flag(sk, SOCK_DBG, valbool);
515 		break;
516 	case SO_REUSEADDR:
517 		sk->sk_reuse = valbool;
518 		break;
519 	case SO_TYPE:
520 	case SO_PROTOCOL:
521 	case SO_DOMAIN:
522 	case SO_ERROR:
523 		ret = -ENOPROTOOPT;
524 		break;
525 	case SO_DONTROUTE:
526 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
527 		break;
528 	case SO_BROADCAST:
529 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
530 		break;
531 	case SO_SNDBUF:
532 		/* Don't error on this BSD doesn't and if you think
533 		   about it this is right. Otherwise apps have to
534 		   play 'guess the biggest size' games. RCVBUF/SNDBUF
535 		   are treated in BSD as hints */
536 
537 		if (val > sysctl_wmem_max)
538 			val = sysctl_wmem_max;
539 set_sndbuf:
540 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
541 		if ((val * 2) < SOCK_MIN_SNDBUF)
542 			sk->sk_sndbuf = SOCK_MIN_SNDBUF;
543 		else
544 			sk->sk_sndbuf = val * 2;
545 
546 		/*
547 		 *	Wake up sending tasks if we
548 		 *	upped the value.
549 		 */
550 		sk->sk_write_space(sk);
551 		break;
552 
553 	case SO_SNDBUFFORCE:
554 		if (!capable(CAP_NET_ADMIN)) {
555 			ret = -EPERM;
556 			break;
557 		}
558 		goto set_sndbuf;
559 
560 	case SO_RCVBUF:
561 		/* Don't error on this BSD doesn't and if you think
562 		   about it this is right. Otherwise apps have to
563 		   play 'guess the biggest size' games. RCVBUF/SNDBUF
564 		   are treated in BSD as hints */
565 
566 		if (val > sysctl_rmem_max)
567 			val = sysctl_rmem_max;
568 set_rcvbuf:
569 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
570 		/*
571 		 * We double it on the way in to account for
572 		 * "struct sk_buff" etc. overhead.   Applications
573 		 * assume that the SO_RCVBUF setting they make will
574 		 * allow that much actual data to be received on that
575 		 * socket.
576 		 *
577 		 * Applications are unaware that "struct sk_buff" and
578 		 * other overheads allocate from the receive buffer
579 		 * during socket buffer allocation.
580 		 *
581 		 * And after considering the possible alternatives,
582 		 * returning the value we actually used in getsockopt
583 		 * is the most desirable behavior.
584 		 */
585 		if ((val * 2) < SOCK_MIN_RCVBUF)
586 			sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
587 		else
588 			sk->sk_rcvbuf = val * 2;
589 		break;
590 
591 	case SO_RCVBUFFORCE:
592 		if (!capable(CAP_NET_ADMIN)) {
593 			ret = -EPERM;
594 			break;
595 		}
596 		goto set_rcvbuf;
597 
598 	case SO_KEEPALIVE:
599 #ifdef CONFIG_INET
600 		if (sk->sk_protocol == IPPROTO_TCP)
601 			tcp_set_keepalive(sk, valbool);
602 #endif
603 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
604 		break;
605 
606 	case SO_OOBINLINE:
607 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
608 		break;
609 
610 	case SO_NO_CHECK:
611 		sk->sk_no_check = valbool;
612 		break;
613 
614 	case SO_PRIORITY:
615 		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
616 			sk->sk_priority = val;
617 		else
618 			ret = -EPERM;
619 		break;
620 
621 	case SO_LINGER:
622 		if (optlen < sizeof(ling)) {
623 			ret = -EINVAL;	/* 1003.1g */
624 			break;
625 		}
626 		if (copy_from_user(&ling, optval, sizeof(ling))) {
627 			ret = -EFAULT;
628 			break;
629 		}
630 		if (!ling.l_onoff)
631 			sock_reset_flag(sk, SOCK_LINGER);
632 		else {
633 #if (BITS_PER_LONG == 32)
634 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
635 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
636 			else
637 #endif
638 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
639 			sock_set_flag(sk, SOCK_LINGER);
640 		}
641 		break;
642 
643 	case SO_BSDCOMPAT:
644 		sock_warn_obsolete_bsdism("setsockopt");
645 		break;
646 
647 	case SO_PASSCRED:
648 		if (valbool)
649 			set_bit(SOCK_PASSCRED, &sock->flags);
650 		else
651 			clear_bit(SOCK_PASSCRED, &sock->flags);
652 		break;
653 
654 	case SO_TIMESTAMP:
655 	case SO_TIMESTAMPNS:
656 		if (valbool)  {
657 			if (optname == SO_TIMESTAMP)
658 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
659 			else
660 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
661 			sock_set_flag(sk, SOCK_RCVTSTAMP);
662 			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
663 		} else {
664 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
665 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
666 		}
667 		break;
668 
669 	case SO_TIMESTAMPING:
670 		if (val & ~SOF_TIMESTAMPING_MASK) {
671 			ret = -EINVAL;
672 			break;
673 		}
674 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
675 				  val & SOF_TIMESTAMPING_TX_HARDWARE);
676 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
677 				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
678 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
679 				  val & SOF_TIMESTAMPING_RX_HARDWARE);
680 		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
681 			sock_enable_timestamp(sk,
682 					      SOCK_TIMESTAMPING_RX_SOFTWARE);
683 		else
684 			sock_disable_timestamp(sk,
685 					       SOCK_TIMESTAMPING_RX_SOFTWARE);
686 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
687 				  val & SOF_TIMESTAMPING_SOFTWARE);
688 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
689 				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
690 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
691 				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
692 		break;
693 
694 	case SO_RCVLOWAT:
695 		if (val < 0)
696 			val = INT_MAX;
697 		sk->sk_rcvlowat = val ? : 1;
698 		break;
699 
700 	case SO_RCVTIMEO:
701 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
702 		break;
703 
704 	case SO_SNDTIMEO:
705 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
706 		break;
707 
708 	case SO_ATTACH_FILTER:
709 		ret = -EINVAL;
710 		if (optlen == sizeof(struct sock_fprog)) {
711 			struct sock_fprog fprog;
712 
713 			ret = -EFAULT;
714 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
715 				break;
716 
717 			ret = sk_attach_filter(&fprog, sk);
718 		}
719 		break;
720 
721 	case SO_DETACH_FILTER:
722 		ret = sk_detach_filter(sk);
723 		break;
724 
725 	case SO_PASSSEC:
726 		if (valbool)
727 			set_bit(SOCK_PASSSEC, &sock->flags);
728 		else
729 			clear_bit(SOCK_PASSSEC, &sock->flags);
730 		break;
731 	case SO_MARK:
732 		if (!capable(CAP_NET_ADMIN))
733 			ret = -EPERM;
734 		else
735 			sk->sk_mark = val;
736 		break;
737 
738 		/* We implement the SO_SNDLOWAT etc to
739 		   not be settable (1003.1g 5.3) */
740 	case SO_RXQ_OVFL:
741 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
742 		break;
743 	default:
744 		ret = -ENOPROTOOPT;
745 		break;
746 	}
747 	release_sock(sk);
748 	return ret;
749 }
750 EXPORT_SYMBOL(sock_setsockopt);
751 
752 
753 void cred_to_ucred(struct pid *pid, const struct cred *cred,
754 		   struct ucred *ucred)
755 {
756 	ucred->pid = pid_vnr(pid);
757 	ucred->uid = ucred->gid = -1;
758 	if (cred) {
759 		struct user_namespace *current_ns = current_user_ns();
760 
761 		ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
762 		ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
763 	}
764 }
765 EXPORT_SYMBOL_GPL(cred_to_ucred);
766 
767 int sock_getsockopt(struct socket *sock, int level, int optname,
768 		    char __user *optval, int __user *optlen)
769 {
770 	struct sock *sk = sock->sk;
771 
772 	union {
773 		int val;
774 		struct linger ling;
775 		struct timeval tm;
776 	} v;
777 
778 	int lv = sizeof(int);
779 	int len;
780 
781 	if (get_user(len, optlen))
782 		return -EFAULT;
783 	if (len < 0)
784 		return -EINVAL;
785 
786 	memset(&v, 0, sizeof(v));
787 
788 	switch (optname) {
789 	case SO_DEBUG:
790 		v.val = sock_flag(sk, SOCK_DBG);
791 		break;
792 
793 	case SO_DONTROUTE:
794 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
795 		break;
796 
797 	case SO_BROADCAST:
798 		v.val = !!sock_flag(sk, SOCK_BROADCAST);
799 		break;
800 
801 	case SO_SNDBUF:
802 		v.val = sk->sk_sndbuf;
803 		break;
804 
805 	case SO_RCVBUF:
806 		v.val = sk->sk_rcvbuf;
807 		break;
808 
809 	case SO_REUSEADDR:
810 		v.val = sk->sk_reuse;
811 		break;
812 
813 	case SO_KEEPALIVE:
814 		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
815 		break;
816 
817 	case SO_TYPE:
818 		v.val = sk->sk_type;
819 		break;
820 
821 	case SO_PROTOCOL:
822 		v.val = sk->sk_protocol;
823 		break;
824 
825 	case SO_DOMAIN:
826 		v.val = sk->sk_family;
827 		break;
828 
829 	case SO_ERROR:
830 		v.val = -sock_error(sk);
831 		if (v.val == 0)
832 			v.val = xchg(&sk->sk_err_soft, 0);
833 		break;
834 
835 	case SO_OOBINLINE:
836 		v.val = !!sock_flag(sk, SOCK_URGINLINE);
837 		break;
838 
839 	case SO_NO_CHECK:
840 		v.val = sk->sk_no_check;
841 		break;
842 
843 	case SO_PRIORITY:
844 		v.val = sk->sk_priority;
845 		break;
846 
847 	case SO_LINGER:
848 		lv		= sizeof(v.ling);
849 		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
850 		v.ling.l_linger	= sk->sk_lingertime / HZ;
851 		break;
852 
853 	case SO_BSDCOMPAT:
854 		sock_warn_obsolete_bsdism("getsockopt");
855 		break;
856 
857 	case SO_TIMESTAMP:
858 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
859 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
860 		break;
861 
862 	case SO_TIMESTAMPNS:
863 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
864 		break;
865 
866 	case SO_TIMESTAMPING:
867 		v.val = 0;
868 		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
869 			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
870 		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
871 			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
872 		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
873 			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
874 		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
875 			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
876 		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
877 			v.val |= SOF_TIMESTAMPING_SOFTWARE;
878 		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
879 			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
880 		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
881 			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
882 		break;
883 
884 	case SO_RCVTIMEO:
885 		lv = sizeof(struct timeval);
886 		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
887 			v.tm.tv_sec = 0;
888 			v.tm.tv_usec = 0;
889 		} else {
890 			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
891 			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
892 		}
893 		break;
894 
895 	case SO_SNDTIMEO:
896 		lv = sizeof(struct timeval);
897 		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
898 			v.tm.tv_sec = 0;
899 			v.tm.tv_usec = 0;
900 		} else {
901 			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
902 			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
903 		}
904 		break;
905 
906 	case SO_RCVLOWAT:
907 		v.val = sk->sk_rcvlowat;
908 		break;
909 
910 	case SO_SNDLOWAT:
911 		v.val = 1;
912 		break;
913 
914 	case SO_PASSCRED:
915 		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
916 		break;
917 
918 	case SO_PEERCRED:
919 	{
920 		struct ucred peercred;
921 		if (len > sizeof(peercred))
922 			len = sizeof(peercred);
923 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
924 		if (copy_to_user(optval, &peercred, len))
925 			return -EFAULT;
926 		goto lenout;
927 	}
928 
929 	case SO_PEERNAME:
930 	{
931 		char address[128];
932 
933 		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
934 			return -ENOTCONN;
935 		if (lv < len)
936 			return -EINVAL;
937 		if (copy_to_user(optval, address, len))
938 			return -EFAULT;
939 		goto lenout;
940 	}
941 
942 	/* Dubious BSD thing... Probably nobody even uses it, but
943 	 * the UNIX standard wants it for whatever reason... -DaveM
944 	 */
945 	case SO_ACCEPTCONN:
946 		v.val = sk->sk_state == TCP_LISTEN;
947 		break;
948 
949 	case SO_PASSSEC:
950 		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
951 		break;
952 
953 	case SO_PEERSEC:
954 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
955 
956 	case SO_MARK:
957 		v.val = sk->sk_mark;
958 		break;
959 
960 	case SO_RXQ_OVFL:
961 		v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
962 		break;
963 
964 	default:
965 		return -ENOPROTOOPT;
966 	}
967 
968 	if (len > lv)
969 		len = lv;
970 	if (copy_to_user(optval, &v, len))
971 		return -EFAULT;
972 lenout:
973 	if (put_user(len, optlen))
974 		return -EFAULT;
975 	return 0;
976 }
977 
978 /*
979  * Initialize an sk_lock.
980  *
981  * (We also register the sk_lock with the lock validator.)
982  */
983 static inline void sock_lock_init(struct sock *sk)
984 {
985 	sock_lock_init_class_and_name(sk,
986 			af_family_slock_key_strings[sk->sk_family],
987 			af_family_slock_keys + sk->sk_family,
988 			af_family_key_strings[sk->sk_family],
989 			af_family_keys + sk->sk_family);
990 }
991 
992 /*
993  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
994  * even temporarly, because of RCU lookups. sk_node should also be left as is.
995  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
996  */
997 static void sock_copy(struct sock *nsk, const struct sock *osk)
998 {
999 #ifdef CONFIG_SECURITY_NETWORK
1000 	void *sptr = nsk->sk_security;
1001 #endif
1002 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1003 
1004 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1005 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1006 
1007 #ifdef CONFIG_SECURITY_NETWORK
1008 	nsk->sk_security = sptr;
1009 	security_sk_clone(osk, nsk);
1010 #endif
1011 }
1012 
1013 /*
1014  * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1015  * un-modified. Special care is taken when initializing object to zero.
1016  */
1017 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1018 {
1019 	if (offsetof(struct sock, sk_node.next) != 0)
1020 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1021 	memset(&sk->sk_node.pprev, 0,
1022 	       size - offsetof(struct sock, sk_node.pprev));
1023 }
1024 
1025 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1026 {
1027 	unsigned long nulls1, nulls2;
1028 
1029 	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1030 	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1031 	if (nulls1 > nulls2)
1032 		swap(nulls1, nulls2);
1033 
1034 	if (nulls1 != 0)
1035 		memset((char *)sk, 0, nulls1);
1036 	memset((char *)sk + nulls1 + sizeof(void *), 0,
1037 	       nulls2 - nulls1 - sizeof(void *));
1038 	memset((char *)sk + nulls2 + sizeof(void *), 0,
1039 	       size - nulls2 - sizeof(void *));
1040 }
1041 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1042 
1043 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1044 		int family)
1045 {
1046 	struct sock *sk;
1047 	struct kmem_cache *slab;
1048 
1049 	slab = prot->slab;
1050 	if (slab != NULL) {
1051 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1052 		if (!sk)
1053 			return sk;
1054 		if (priority & __GFP_ZERO) {
1055 			if (prot->clear_sk)
1056 				prot->clear_sk(sk, prot->obj_size);
1057 			else
1058 				sk_prot_clear_nulls(sk, prot->obj_size);
1059 		}
1060 	} else
1061 		sk = kmalloc(prot->obj_size, priority);
1062 
1063 	if (sk != NULL) {
1064 		kmemcheck_annotate_bitfield(sk, flags);
1065 
1066 		if (security_sk_alloc(sk, family, priority))
1067 			goto out_free;
1068 
1069 		if (!try_module_get(prot->owner))
1070 			goto out_free_sec;
1071 		sk_tx_queue_clear(sk);
1072 	}
1073 
1074 	return sk;
1075 
1076 out_free_sec:
1077 	security_sk_free(sk);
1078 out_free:
1079 	if (slab != NULL)
1080 		kmem_cache_free(slab, sk);
1081 	else
1082 		kfree(sk);
1083 	return NULL;
1084 }
1085 
1086 static void sk_prot_free(struct proto *prot, struct sock *sk)
1087 {
1088 	struct kmem_cache *slab;
1089 	struct module *owner;
1090 
1091 	owner = prot->owner;
1092 	slab = prot->slab;
1093 
1094 	security_sk_free(sk);
1095 	if (slab != NULL)
1096 		kmem_cache_free(slab, sk);
1097 	else
1098 		kfree(sk);
1099 	module_put(owner);
1100 }
1101 
1102 #ifdef CONFIG_CGROUPS
1103 void sock_update_classid(struct sock *sk)
1104 {
1105 	u32 classid;
1106 
1107 	rcu_read_lock();  /* doing current task, which cannot vanish. */
1108 	classid = task_cls_classid(current);
1109 	rcu_read_unlock();
1110 	if (classid && classid != sk->sk_classid)
1111 		sk->sk_classid = classid;
1112 }
1113 EXPORT_SYMBOL(sock_update_classid);
1114 #endif
1115 
1116 /**
1117  *	sk_alloc - All socket objects are allocated here
1118  *	@net: the applicable net namespace
1119  *	@family: protocol family
1120  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1121  *	@prot: struct proto associated with this new sock instance
1122  */
1123 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1124 		      struct proto *prot)
1125 {
1126 	struct sock *sk;
1127 
1128 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1129 	if (sk) {
1130 		sk->sk_family = family;
1131 		/*
1132 		 * See comment in struct sock definition to understand
1133 		 * why we need sk_prot_creator -acme
1134 		 */
1135 		sk->sk_prot = sk->sk_prot_creator = prot;
1136 		sock_lock_init(sk);
1137 		sock_net_set(sk, get_net(net));
1138 		atomic_set(&sk->sk_wmem_alloc, 1);
1139 
1140 		sock_update_classid(sk);
1141 	}
1142 
1143 	return sk;
1144 }
1145 EXPORT_SYMBOL(sk_alloc);
1146 
1147 static void __sk_free(struct sock *sk)
1148 {
1149 	struct sk_filter *filter;
1150 
1151 	if (sk->sk_destruct)
1152 		sk->sk_destruct(sk);
1153 
1154 	filter = rcu_dereference_check(sk->sk_filter,
1155 				       atomic_read(&sk->sk_wmem_alloc) == 0);
1156 	if (filter) {
1157 		sk_filter_uncharge(sk, filter);
1158 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1159 	}
1160 
1161 	sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1162 	sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1163 
1164 	if (atomic_read(&sk->sk_omem_alloc))
1165 		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1166 		       __func__, atomic_read(&sk->sk_omem_alloc));
1167 
1168 	if (sk->sk_peer_cred)
1169 		put_cred(sk->sk_peer_cred);
1170 	put_pid(sk->sk_peer_pid);
1171 	put_net(sock_net(sk));
1172 	sk_prot_free(sk->sk_prot_creator, sk);
1173 }
1174 
1175 void sk_free(struct sock *sk)
1176 {
1177 	/*
1178 	 * We subtract one from sk_wmem_alloc and can know if
1179 	 * some packets are still in some tx queue.
1180 	 * If not null, sock_wfree() will call __sk_free(sk) later
1181 	 */
1182 	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1183 		__sk_free(sk);
1184 }
1185 EXPORT_SYMBOL(sk_free);
1186 
1187 /*
1188  * Last sock_put should drop reference to sk->sk_net. It has already
1189  * been dropped in sk_change_net. Taking reference to stopping namespace
1190  * is not an option.
1191  * Take reference to a socket to remove it from hash _alive_ and after that
1192  * destroy it in the context of init_net.
1193  */
1194 void sk_release_kernel(struct sock *sk)
1195 {
1196 	if (sk == NULL || sk->sk_socket == NULL)
1197 		return;
1198 
1199 	sock_hold(sk);
1200 	sock_release(sk->sk_socket);
1201 	release_net(sock_net(sk));
1202 	sock_net_set(sk, get_net(&init_net));
1203 	sock_put(sk);
1204 }
1205 EXPORT_SYMBOL(sk_release_kernel);
1206 
1207 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1208 {
1209 	struct sock *newsk;
1210 
1211 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1212 	if (newsk != NULL) {
1213 		struct sk_filter *filter;
1214 
1215 		sock_copy(newsk, sk);
1216 
1217 		/* SANITY */
1218 		get_net(sock_net(newsk));
1219 		sk_node_init(&newsk->sk_node);
1220 		sock_lock_init(newsk);
1221 		bh_lock_sock(newsk);
1222 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1223 		newsk->sk_backlog.len = 0;
1224 
1225 		atomic_set(&newsk->sk_rmem_alloc, 0);
1226 		/*
1227 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1228 		 */
1229 		atomic_set(&newsk->sk_wmem_alloc, 1);
1230 		atomic_set(&newsk->sk_omem_alloc, 0);
1231 		skb_queue_head_init(&newsk->sk_receive_queue);
1232 		skb_queue_head_init(&newsk->sk_write_queue);
1233 #ifdef CONFIG_NET_DMA
1234 		skb_queue_head_init(&newsk->sk_async_wait_queue);
1235 #endif
1236 
1237 		spin_lock_init(&newsk->sk_dst_lock);
1238 		rwlock_init(&newsk->sk_callback_lock);
1239 		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1240 				af_callback_keys + newsk->sk_family,
1241 				af_family_clock_key_strings[newsk->sk_family]);
1242 
1243 		newsk->sk_dst_cache	= NULL;
1244 		newsk->sk_wmem_queued	= 0;
1245 		newsk->sk_forward_alloc = 0;
1246 		newsk->sk_send_head	= NULL;
1247 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1248 
1249 		sock_reset_flag(newsk, SOCK_DONE);
1250 		skb_queue_head_init(&newsk->sk_error_queue);
1251 
1252 		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1253 		if (filter != NULL)
1254 			sk_filter_charge(newsk, filter);
1255 
1256 		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1257 			/* It is still raw copy of parent, so invalidate
1258 			 * destructor and make plain sk_free() */
1259 			newsk->sk_destruct = NULL;
1260 			bh_unlock_sock(newsk);
1261 			sk_free(newsk);
1262 			newsk = NULL;
1263 			goto out;
1264 		}
1265 
1266 		newsk->sk_err	   = 0;
1267 		newsk->sk_priority = 0;
1268 		/*
1269 		 * Before updating sk_refcnt, we must commit prior changes to memory
1270 		 * (Documentation/RCU/rculist_nulls.txt for details)
1271 		 */
1272 		smp_wmb();
1273 		atomic_set(&newsk->sk_refcnt, 2);
1274 
1275 		/*
1276 		 * Increment the counter in the same struct proto as the master
1277 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1278 		 * is the same as sk->sk_prot->socks, as this field was copied
1279 		 * with memcpy).
1280 		 *
1281 		 * This _changes_ the previous behaviour, where
1282 		 * tcp_create_openreq_child always was incrementing the
1283 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1284 		 * to be taken into account in all callers. -acme
1285 		 */
1286 		sk_refcnt_debug_inc(newsk);
1287 		sk_set_socket(newsk, NULL);
1288 		newsk->sk_wq = NULL;
1289 
1290 		if (newsk->sk_prot->sockets_allocated)
1291 			percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1292 
1293 		if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1294 		    sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1295 			net_enable_timestamp();
1296 	}
1297 out:
1298 	return newsk;
1299 }
1300 EXPORT_SYMBOL_GPL(sk_clone);
1301 
1302 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1303 {
1304 	__sk_dst_set(sk, dst);
1305 	sk->sk_route_caps = dst->dev->features;
1306 	if (sk->sk_route_caps & NETIF_F_GSO)
1307 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1308 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1309 	if (sk_can_gso(sk)) {
1310 		if (dst->header_len) {
1311 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1312 		} else {
1313 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1314 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1315 		}
1316 	}
1317 }
1318 EXPORT_SYMBOL_GPL(sk_setup_caps);
1319 
1320 void __init sk_init(void)
1321 {
1322 	if (totalram_pages <= 4096) {
1323 		sysctl_wmem_max = 32767;
1324 		sysctl_rmem_max = 32767;
1325 		sysctl_wmem_default = 32767;
1326 		sysctl_rmem_default = 32767;
1327 	} else if (totalram_pages >= 131072) {
1328 		sysctl_wmem_max = 131071;
1329 		sysctl_rmem_max = 131071;
1330 	}
1331 }
1332 
1333 /*
1334  *	Simple resource managers for sockets.
1335  */
1336 
1337 
1338 /*
1339  * Write buffer destructor automatically called from kfree_skb.
1340  */
1341 void sock_wfree(struct sk_buff *skb)
1342 {
1343 	struct sock *sk = skb->sk;
1344 	unsigned int len = skb->truesize;
1345 
1346 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1347 		/*
1348 		 * Keep a reference on sk_wmem_alloc, this will be released
1349 		 * after sk_write_space() call
1350 		 */
1351 		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1352 		sk->sk_write_space(sk);
1353 		len = 1;
1354 	}
1355 	/*
1356 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1357 	 * could not do because of in-flight packets
1358 	 */
1359 	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1360 		__sk_free(sk);
1361 }
1362 EXPORT_SYMBOL(sock_wfree);
1363 
1364 /*
1365  * Read buffer destructor automatically called from kfree_skb.
1366  */
1367 void sock_rfree(struct sk_buff *skb)
1368 {
1369 	struct sock *sk = skb->sk;
1370 	unsigned int len = skb->truesize;
1371 
1372 	atomic_sub(len, &sk->sk_rmem_alloc);
1373 	sk_mem_uncharge(sk, len);
1374 }
1375 EXPORT_SYMBOL(sock_rfree);
1376 
1377 
1378 int sock_i_uid(struct sock *sk)
1379 {
1380 	int uid;
1381 
1382 	read_lock_bh(&sk->sk_callback_lock);
1383 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1384 	read_unlock_bh(&sk->sk_callback_lock);
1385 	return uid;
1386 }
1387 EXPORT_SYMBOL(sock_i_uid);
1388 
1389 unsigned long sock_i_ino(struct sock *sk)
1390 {
1391 	unsigned long ino;
1392 
1393 	read_lock_bh(&sk->sk_callback_lock);
1394 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1395 	read_unlock_bh(&sk->sk_callback_lock);
1396 	return ino;
1397 }
1398 EXPORT_SYMBOL(sock_i_ino);
1399 
1400 /*
1401  * Allocate a skb from the socket's send buffer.
1402  */
1403 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1404 			     gfp_t priority)
1405 {
1406 	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1407 		struct sk_buff *skb = alloc_skb(size, priority);
1408 		if (skb) {
1409 			skb_set_owner_w(skb, sk);
1410 			return skb;
1411 		}
1412 	}
1413 	return NULL;
1414 }
1415 EXPORT_SYMBOL(sock_wmalloc);
1416 
1417 /*
1418  * Allocate a skb from the socket's receive buffer.
1419  */
1420 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1421 			     gfp_t priority)
1422 {
1423 	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1424 		struct sk_buff *skb = alloc_skb(size, priority);
1425 		if (skb) {
1426 			skb_set_owner_r(skb, sk);
1427 			return skb;
1428 		}
1429 	}
1430 	return NULL;
1431 }
1432 
1433 /*
1434  * Allocate a memory block from the socket's option memory buffer.
1435  */
1436 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1437 {
1438 	if ((unsigned)size <= sysctl_optmem_max &&
1439 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1440 		void *mem;
1441 		/* First do the add, to avoid the race if kmalloc
1442 		 * might sleep.
1443 		 */
1444 		atomic_add(size, &sk->sk_omem_alloc);
1445 		mem = kmalloc(size, priority);
1446 		if (mem)
1447 			return mem;
1448 		atomic_sub(size, &sk->sk_omem_alloc);
1449 	}
1450 	return NULL;
1451 }
1452 EXPORT_SYMBOL(sock_kmalloc);
1453 
1454 /*
1455  * Free an option memory block.
1456  */
1457 void sock_kfree_s(struct sock *sk, void *mem, int size)
1458 {
1459 	kfree(mem);
1460 	atomic_sub(size, &sk->sk_omem_alloc);
1461 }
1462 EXPORT_SYMBOL(sock_kfree_s);
1463 
1464 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1465    I think, these locks should be removed for datagram sockets.
1466  */
1467 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1468 {
1469 	DEFINE_WAIT(wait);
1470 
1471 	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1472 	for (;;) {
1473 		if (!timeo)
1474 			break;
1475 		if (signal_pending(current))
1476 			break;
1477 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1478 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1479 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1480 			break;
1481 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1482 			break;
1483 		if (sk->sk_err)
1484 			break;
1485 		timeo = schedule_timeout(timeo);
1486 	}
1487 	finish_wait(sk_sleep(sk), &wait);
1488 	return timeo;
1489 }
1490 
1491 
1492 /*
1493  *	Generic send/receive buffer handlers
1494  */
1495 
1496 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1497 				     unsigned long data_len, int noblock,
1498 				     int *errcode)
1499 {
1500 	struct sk_buff *skb;
1501 	gfp_t gfp_mask;
1502 	long timeo;
1503 	int err;
1504 
1505 	gfp_mask = sk->sk_allocation;
1506 	if (gfp_mask & __GFP_WAIT)
1507 		gfp_mask |= __GFP_REPEAT;
1508 
1509 	timeo = sock_sndtimeo(sk, noblock);
1510 	while (1) {
1511 		err = sock_error(sk);
1512 		if (err != 0)
1513 			goto failure;
1514 
1515 		err = -EPIPE;
1516 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1517 			goto failure;
1518 
1519 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1520 			skb = alloc_skb(header_len, gfp_mask);
1521 			if (skb) {
1522 				int npages;
1523 				int i;
1524 
1525 				/* No pages, we're done... */
1526 				if (!data_len)
1527 					break;
1528 
1529 				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1530 				skb->truesize += data_len;
1531 				skb_shinfo(skb)->nr_frags = npages;
1532 				for (i = 0; i < npages; i++) {
1533 					struct page *page;
1534 
1535 					page = alloc_pages(sk->sk_allocation, 0);
1536 					if (!page) {
1537 						err = -ENOBUFS;
1538 						skb_shinfo(skb)->nr_frags = i;
1539 						kfree_skb(skb);
1540 						goto failure;
1541 					}
1542 
1543 					__skb_fill_page_desc(skb, i,
1544 							page, 0,
1545 							(data_len >= PAGE_SIZE ?
1546 							 PAGE_SIZE :
1547 							 data_len));
1548 					data_len -= PAGE_SIZE;
1549 				}
1550 
1551 				/* Full success... */
1552 				break;
1553 			}
1554 			err = -ENOBUFS;
1555 			goto failure;
1556 		}
1557 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1558 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1559 		err = -EAGAIN;
1560 		if (!timeo)
1561 			goto failure;
1562 		if (signal_pending(current))
1563 			goto interrupted;
1564 		timeo = sock_wait_for_wmem(sk, timeo);
1565 	}
1566 
1567 	skb_set_owner_w(skb, sk);
1568 	return skb;
1569 
1570 interrupted:
1571 	err = sock_intr_errno(timeo);
1572 failure:
1573 	*errcode = err;
1574 	return NULL;
1575 }
1576 EXPORT_SYMBOL(sock_alloc_send_pskb);
1577 
1578 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1579 				    int noblock, int *errcode)
1580 {
1581 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1582 }
1583 EXPORT_SYMBOL(sock_alloc_send_skb);
1584 
1585 static void __lock_sock(struct sock *sk)
1586 	__releases(&sk->sk_lock.slock)
1587 	__acquires(&sk->sk_lock.slock)
1588 {
1589 	DEFINE_WAIT(wait);
1590 
1591 	for (;;) {
1592 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1593 					TASK_UNINTERRUPTIBLE);
1594 		spin_unlock_bh(&sk->sk_lock.slock);
1595 		schedule();
1596 		spin_lock_bh(&sk->sk_lock.slock);
1597 		if (!sock_owned_by_user(sk))
1598 			break;
1599 	}
1600 	finish_wait(&sk->sk_lock.wq, &wait);
1601 }
1602 
1603 static void __release_sock(struct sock *sk)
1604 	__releases(&sk->sk_lock.slock)
1605 	__acquires(&sk->sk_lock.slock)
1606 {
1607 	struct sk_buff *skb = sk->sk_backlog.head;
1608 
1609 	do {
1610 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1611 		bh_unlock_sock(sk);
1612 
1613 		do {
1614 			struct sk_buff *next = skb->next;
1615 
1616 			WARN_ON_ONCE(skb_dst_is_noref(skb));
1617 			skb->next = NULL;
1618 			sk_backlog_rcv(sk, skb);
1619 
1620 			/*
1621 			 * We are in process context here with softirqs
1622 			 * disabled, use cond_resched_softirq() to preempt.
1623 			 * This is safe to do because we've taken the backlog
1624 			 * queue private:
1625 			 */
1626 			cond_resched_softirq();
1627 
1628 			skb = next;
1629 		} while (skb != NULL);
1630 
1631 		bh_lock_sock(sk);
1632 	} while ((skb = sk->sk_backlog.head) != NULL);
1633 
1634 	/*
1635 	 * Doing the zeroing here guarantee we can not loop forever
1636 	 * while a wild producer attempts to flood us.
1637 	 */
1638 	sk->sk_backlog.len = 0;
1639 }
1640 
1641 /**
1642  * sk_wait_data - wait for data to arrive at sk_receive_queue
1643  * @sk:    sock to wait on
1644  * @timeo: for how long
1645  *
1646  * Now socket state including sk->sk_err is changed only under lock,
1647  * hence we may omit checks after joining wait queue.
1648  * We check receive queue before schedule() only as optimization;
1649  * it is very likely that release_sock() added new data.
1650  */
1651 int sk_wait_data(struct sock *sk, long *timeo)
1652 {
1653 	int rc;
1654 	DEFINE_WAIT(wait);
1655 
1656 	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1657 	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1658 	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1659 	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1660 	finish_wait(sk_sleep(sk), &wait);
1661 	return rc;
1662 }
1663 EXPORT_SYMBOL(sk_wait_data);
1664 
1665 /**
1666  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1667  *	@sk: socket
1668  *	@size: memory size to allocate
1669  *	@kind: allocation type
1670  *
1671  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1672  *	rmem allocation. This function assumes that protocols which have
1673  *	memory_pressure use sk_wmem_queued as write buffer accounting.
1674  */
1675 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1676 {
1677 	struct proto *prot = sk->sk_prot;
1678 	int amt = sk_mem_pages(size);
1679 	long allocated;
1680 
1681 	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1682 	allocated = atomic_long_add_return(amt, prot->memory_allocated);
1683 
1684 	/* Under limit. */
1685 	if (allocated <= prot->sysctl_mem[0]) {
1686 		if (prot->memory_pressure && *prot->memory_pressure)
1687 			*prot->memory_pressure = 0;
1688 		return 1;
1689 	}
1690 
1691 	/* Under pressure. */
1692 	if (allocated > prot->sysctl_mem[1])
1693 		if (prot->enter_memory_pressure)
1694 			prot->enter_memory_pressure(sk);
1695 
1696 	/* Over hard limit. */
1697 	if (allocated > prot->sysctl_mem[2])
1698 		goto suppress_allocation;
1699 
1700 	/* guarantee minimum buffer size under pressure */
1701 	if (kind == SK_MEM_RECV) {
1702 		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1703 			return 1;
1704 	} else { /* SK_MEM_SEND */
1705 		if (sk->sk_type == SOCK_STREAM) {
1706 			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1707 				return 1;
1708 		} else if (atomic_read(&sk->sk_wmem_alloc) <
1709 			   prot->sysctl_wmem[0])
1710 				return 1;
1711 	}
1712 
1713 	if (prot->memory_pressure) {
1714 		int alloc;
1715 
1716 		if (!*prot->memory_pressure)
1717 			return 1;
1718 		alloc = percpu_counter_read_positive(prot->sockets_allocated);
1719 		if (prot->sysctl_mem[2] > alloc *
1720 		    sk_mem_pages(sk->sk_wmem_queued +
1721 				 atomic_read(&sk->sk_rmem_alloc) +
1722 				 sk->sk_forward_alloc))
1723 			return 1;
1724 	}
1725 
1726 suppress_allocation:
1727 
1728 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1729 		sk_stream_moderate_sndbuf(sk);
1730 
1731 		/* Fail only if socket is _under_ its sndbuf.
1732 		 * In this case we cannot block, so that we have to fail.
1733 		 */
1734 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1735 			return 1;
1736 	}
1737 
1738 	trace_sock_exceed_buf_limit(sk, prot, allocated);
1739 
1740 	/* Alas. Undo changes. */
1741 	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1742 	atomic_long_sub(amt, prot->memory_allocated);
1743 	return 0;
1744 }
1745 EXPORT_SYMBOL(__sk_mem_schedule);
1746 
1747 /**
1748  *	__sk_reclaim - reclaim memory_allocated
1749  *	@sk: socket
1750  */
1751 void __sk_mem_reclaim(struct sock *sk)
1752 {
1753 	struct proto *prot = sk->sk_prot;
1754 
1755 	atomic_long_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1756 		   prot->memory_allocated);
1757 	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1758 
1759 	if (prot->memory_pressure && *prot->memory_pressure &&
1760 	    (atomic_long_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1761 		*prot->memory_pressure = 0;
1762 }
1763 EXPORT_SYMBOL(__sk_mem_reclaim);
1764 
1765 
1766 /*
1767  * Set of default routines for initialising struct proto_ops when
1768  * the protocol does not support a particular function. In certain
1769  * cases where it makes no sense for a protocol to have a "do nothing"
1770  * function, some default processing is provided.
1771  */
1772 
1773 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1774 {
1775 	return -EOPNOTSUPP;
1776 }
1777 EXPORT_SYMBOL(sock_no_bind);
1778 
1779 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1780 		    int len, int flags)
1781 {
1782 	return -EOPNOTSUPP;
1783 }
1784 EXPORT_SYMBOL(sock_no_connect);
1785 
1786 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1787 {
1788 	return -EOPNOTSUPP;
1789 }
1790 EXPORT_SYMBOL(sock_no_socketpair);
1791 
1792 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1793 {
1794 	return -EOPNOTSUPP;
1795 }
1796 EXPORT_SYMBOL(sock_no_accept);
1797 
1798 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1799 		    int *len, int peer)
1800 {
1801 	return -EOPNOTSUPP;
1802 }
1803 EXPORT_SYMBOL(sock_no_getname);
1804 
1805 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1806 {
1807 	return 0;
1808 }
1809 EXPORT_SYMBOL(sock_no_poll);
1810 
1811 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1812 {
1813 	return -EOPNOTSUPP;
1814 }
1815 EXPORT_SYMBOL(sock_no_ioctl);
1816 
1817 int sock_no_listen(struct socket *sock, int backlog)
1818 {
1819 	return -EOPNOTSUPP;
1820 }
1821 EXPORT_SYMBOL(sock_no_listen);
1822 
1823 int sock_no_shutdown(struct socket *sock, int how)
1824 {
1825 	return -EOPNOTSUPP;
1826 }
1827 EXPORT_SYMBOL(sock_no_shutdown);
1828 
1829 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1830 		    char __user *optval, unsigned int optlen)
1831 {
1832 	return -EOPNOTSUPP;
1833 }
1834 EXPORT_SYMBOL(sock_no_setsockopt);
1835 
1836 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1837 		    char __user *optval, int __user *optlen)
1838 {
1839 	return -EOPNOTSUPP;
1840 }
1841 EXPORT_SYMBOL(sock_no_getsockopt);
1842 
1843 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1844 		    size_t len)
1845 {
1846 	return -EOPNOTSUPP;
1847 }
1848 EXPORT_SYMBOL(sock_no_sendmsg);
1849 
1850 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1851 		    size_t len, int flags)
1852 {
1853 	return -EOPNOTSUPP;
1854 }
1855 EXPORT_SYMBOL(sock_no_recvmsg);
1856 
1857 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1858 {
1859 	/* Mirror missing mmap method error code */
1860 	return -ENODEV;
1861 }
1862 EXPORT_SYMBOL(sock_no_mmap);
1863 
1864 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1865 {
1866 	ssize_t res;
1867 	struct msghdr msg = {.msg_flags = flags};
1868 	struct kvec iov;
1869 	char *kaddr = kmap(page);
1870 	iov.iov_base = kaddr + offset;
1871 	iov.iov_len = size;
1872 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1873 	kunmap(page);
1874 	return res;
1875 }
1876 EXPORT_SYMBOL(sock_no_sendpage);
1877 
1878 /*
1879  *	Default Socket Callbacks
1880  */
1881 
1882 static void sock_def_wakeup(struct sock *sk)
1883 {
1884 	struct socket_wq *wq;
1885 
1886 	rcu_read_lock();
1887 	wq = rcu_dereference(sk->sk_wq);
1888 	if (wq_has_sleeper(wq))
1889 		wake_up_interruptible_all(&wq->wait);
1890 	rcu_read_unlock();
1891 }
1892 
1893 static void sock_def_error_report(struct sock *sk)
1894 {
1895 	struct socket_wq *wq;
1896 
1897 	rcu_read_lock();
1898 	wq = rcu_dereference(sk->sk_wq);
1899 	if (wq_has_sleeper(wq))
1900 		wake_up_interruptible_poll(&wq->wait, POLLERR);
1901 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1902 	rcu_read_unlock();
1903 }
1904 
1905 static void sock_def_readable(struct sock *sk, int len)
1906 {
1907 	struct socket_wq *wq;
1908 
1909 	rcu_read_lock();
1910 	wq = rcu_dereference(sk->sk_wq);
1911 	if (wq_has_sleeper(wq))
1912 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
1913 						POLLRDNORM | POLLRDBAND);
1914 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1915 	rcu_read_unlock();
1916 }
1917 
1918 static void sock_def_write_space(struct sock *sk)
1919 {
1920 	struct socket_wq *wq;
1921 
1922 	rcu_read_lock();
1923 
1924 	/* Do not wake up a writer until he can make "significant"
1925 	 * progress.  --DaveM
1926 	 */
1927 	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1928 		wq = rcu_dereference(sk->sk_wq);
1929 		if (wq_has_sleeper(wq))
1930 			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1931 						POLLWRNORM | POLLWRBAND);
1932 
1933 		/* Should agree with poll, otherwise some programs break */
1934 		if (sock_writeable(sk))
1935 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1936 	}
1937 
1938 	rcu_read_unlock();
1939 }
1940 
1941 static void sock_def_destruct(struct sock *sk)
1942 {
1943 	kfree(sk->sk_protinfo);
1944 }
1945 
1946 void sk_send_sigurg(struct sock *sk)
1947 {
1948 	if (sk->sk_socket && sk->sk_socket->file)
1949 		if (send_sigurg(&sk->sk_socket->file->f_owner))
1950 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1951 }
1952 EXPORT_SYMBOL(sk_send_sigurg);
1953 
1954 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1955 		    unsigned long expires)
1956 {
1957 	if (!mod_timer(timer, expires))
1958 		sock_hold(sk);
1959 }
1960 EXPORT_SYMBOL(sk_reset_timer);
1961 
1962 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1963 {
1964 	if (timer_pending(timer) && del_timer(timer))
1965 		__sock_put(sk);
1966 }
1967 EXPORT_SYMBOL(sk_stop_timer);
1968 
1969 void sock_init_data(struct socket *sock, struct sock *sk)
1970 {
1971 	skb_queue_head_init(&sk->sk_receive_queue);
1972 	skb_queue_head_init(&sk->sk_write_queue);
1973 	skb_queue_head_init(&sk->sk_error_queue);
1974 #ifdef CONFIG_NET_DMA
1975 	skb_queue_head_init(&sk->sk_async_wait_queue);
1976 #endif
1977 
1978 	sk->sk_send_head	=	NULL;
1979 
1980 	init_timer(&sk->sk_timer);
1981 
1982 	sk->sk_allocation	=	GFP_KERNEL;
1983 	sk->sk_rcvbuf		=	sysctl_rmem_default;
1984 	sk->sk_sndbuf		=	sysctl_wmem_default;
1985 	sk->sk_state		=	TCP_CLOSE;
1986 	sk_set_socket(sk, sock);
1987 
1988 	sock_set_flag(sk, SOCK_ZAPPED);
1989 
1990 	if (sock) {
1991 		sk->sk_type	=	sock->type;
1992 		sk->sk_wq	=	sock->wq;
1993 		sock->sk	=	sk;
1994 	} else
1995 		sk->sk_wq	=	NULL;
1996 
1997 	spin_lock_init(&sk->sk_dst_lock);
1998 	rwlock_init(&sk->sk_callback_lock);
1999 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2000 			af_callback_keys + sk->sk_family,
2001 			af_family_clock_key_strings[sk->sk_family]);
2002 
2003 	sk->sk_state_change	=	sock_def_wakeup;
2004 	sk->sk_data_ready	=	sock_def_readable;
2005 	sk->sk_write_space	=	sock_def_write_space;
2006 	sk->sk_error_report	=	sock_def_error_report;
2007 	sk->sk_destruct		=	sock_def_destruct;
2008 
2009 	sk->sk_sndmsg_page	=	NULL;
2010 	sk->sk_sndmsg_off	=	0;
2011 
2012 	sk->sk_peer_pid 	=	NULL;
2013 	sk->sk_peer_cred	=	NULL;
2014 	sk->sk_write_pending	=	0;
2015 	sk->sk_rcvlowat		=	1;
2016 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2017 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2018 
2019 	sk->sk_stamp = ktime_set(-1L, 0);
2020 
2021 	/*
2022 	 * Before updating sk_refcnt, we must commit prior changes to memory
2023 	 * (Documentation/RCU/rculist_nulls.txt for details)
2024 	 */
2025 	smp_wmb();
2026 	atomic_set(&sk->sk_refcnt, 1);
2027 	atomic_set(&sk->sk_drops, 0);
2028 }
2029 EXPORT_SYMBOL(sock_init_data);
2030 
2031 void lock_sock_nested(struct sock *sk, int subclass)
2032 {
2033 	might_sleep();
2034 	spin_lock_bh(&sk->sk_lock.slock);
2035 	if (sk->sk_lock.owned)
2036 		__lock_sock(sk);
2037 	sk->sk_lock.owned = 1;
2038 	spin_unlock(&sk->sk_lock.slock);
2039 	/*
2040 	 * The sk_lock has mutex_lock() semantics here:
2041 	 */
2042 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2043 	local_bh_enable();
2044 }
2045 EXPORT_SYMBOL(lock_sock_nested);
2046 
2047 void release_sock(struct sock *sk)
2048 {
2049 	/*
2050 	 * The sk_lock has mutex_unlock() semantics:
2051 	 */
2052 	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2053 
2054 	spin_lock_bh(&sk->sk_lock.slock);
2055 	if (sk->sk_backlog.tail)
2056 		__release_sock(sk);
2057 	sk->sk_lock.owned = 0;
2058 	if (waitqueue_active(&sk->sk_lock.wq))
2059 		wake_up(&sk->sk_lock.wq);
2060 	spin_unlock_bh(&sk->sk_lock.slock);
2061 }
2062 EXPORT_SYMBOL(release_sock);
2063 
2064 /**
2065  * lock_sock_fast - fast version of lock_sock
2066  * @sk: socket
2067  *
2068  * This version should be used for very small section, where process wont block
2069  * return false if fast path is taken
2070  *   sk_lock.slock locked, owned = 0, BH disabled
2071  * return true if slow path is taken
2072  *   sk_lock.slock unlocked, owned = 1, BH enabled
2073  */
2074 bool lock_sock_fast(struct sock *sk)
2075 {
2076 	might_sleep();
2077 	spin_lock_bh(&sk->sk_lock.slock);
2078 
2079 	if (!sk->sk_lock.owned)
2080 		/*
2081 		 * Note : We must disable BH
2082 		 */
2083 		return false;
2084 
2085 	__lock_sock(sk);
2086 	sk->sk_lock.owned = 1;
2087 	spin_unlock(&sk->sk_lock.slock);
2088 	/*
2089 	 * The sk_lock has mutex_lock() semantics here:
2090 	 */
2091 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2092 	local_bh_enable();
2093 	return true;
2094 }
2095 EXPORT_SYMBOL(lock_sock_fast);
2096 
2097 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2098 {
2099 	struct timeval tv;
2100 	if (!sock_flag(sk, SOCK_TIMESTAMP))
2101 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2102 	tv = ktime_to_timeval(sk->sk_stamp);
2103 	if (tv.tv_sec == -1)
2104 		return -ENOENT;
2105 	if (tv.tv_sec == 0) {
2106 		sk->sk_stamp = ktime_get_real();
2107 		tv = ktime_to_timeval(sk->sk_stamp);
2108 	}
2109 	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2110 }
2111 EXPORT_SYMBOL(sock_get_timestamp);
2112 
2113 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2114 {
2115 	struct timespec ts;
2116 	if (!sock_flag(sk, SOCK_TIMESTAMP))
2117 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2118 	ts = ktime_to_timespec(sk->sk_stamp);
2119 	if (ts.tv_sec == -1)
2120 		return -ENOENT;
2121 	if (ts.tv_sec == 0) {
2122 		sk->sk_stamp = ktime_get_real();
2123 		ts = ktime_to_timespec(sk->sk_stamp);
2124 	}
2125 	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2126 }
2127 EXPORT_SYMBOL(sock_get_timestampns);
2128 
2129 void sock_enable_timestamp(struct sock *sk, int flag)
2130 {
2131 	if (!sock_flag(sk, flag)) {
2132 		sock_set_flag(sk, flag);
2133 		/*
2134 		 * we just set one of the two flags which require net
2135 		 * time stamping, but time stamping might have been on
2136 		 * already because of the other one
2137 		 */
2138 		if (!sock_flag(sk,
2139 				flag == SOCK_TIMESTAMP ?
2140 				SOCK_TIMESTAMPING_RX_SOFTWARE :
2141 				SOCK_TIMESTAMP))
2142 			net_enable_timestamp();
2143 	}
2144 }
2145 
2146 /*
2147  *	Get a socket option on an socket.
2148  *
2149  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2150  *	asynchronous errors should be reported by getsockopt. We assume
2151  *	this means if you specify SO_ERROR (otherwise whats the point of it).
2152  */
2153 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2154 			   char __user *optval, int __user *optlen)
2155 {
2156 	struct sock *sk = sock->sk;
2157 
2158 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2159 }
2160 EXPORT_SYMBOL(sock_common_getsockopt);
2161 
2162 #ifdef CONFIG_COMPAT
2163 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2164 				  char __user *optval, int __user *optlen)
2165 {
2166 	struct sock *sk = sock->sk;
2167 
2168 	if (sk->sk_prot->compat_getsockopt != NULL)
2169 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2170 						      optval, optlen);
2171 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2172 }
2173 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2174 #endif
2175 
2176 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2177 			struct msghdr *msg, size_t size, int flags)
2178 {
2179 	struct sock *sk = sock->sk;
2180 	int addr_len = 0;
2181 	int err;
2182 
2183 	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2184 				   flags & ~MSG_DONTWAIT, &addr_len);
2185 	if (err >= 0)
2186 		msg->msg_namelen = addr_len;
2187 	return err;
2188 }
2189 EXPORT_SYMBOL(sock_common_recvmsg);
2190 
2191 /*
2192  *	Set socket options on an inet socket.
2193  */
2194 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2195 			   char __user *optval, unsigned int optlen)
2196 {
2197 	struct sock *sk = sock->sk;
2198 
2199 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2200 }
2201 EXPORT_SYMBOL(sock_common_setsockopt);
2202 
2203 #ifdef CONFIG_COMPAT
2204 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2205 				  char __user *optval, unsigned int optlen)
2206 {
2207 	struct sock *sk = sock->sk;
2208 
2209 	if (sk->sk_prot->compat_setsockopt != NULL)
2210 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2211 						      optval, optlen);
2212 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2213 }
2214 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2215 #endif
2216 
2217 void sk_common_release(struct sock *sk)
2218 {
2219 	if (sk->sk_prot->destroy)
2220 		sk->sk_prot->destroy(sk);
2221 
2222 	/*
2223 	 * Observation: when sock_common_release is called, processes have
2224 	 * no access to socket. But net still has.
2225 	 * Step one, detach it from networking:
2226 	 *
2227 	 * A. Remove from hash tables.
2228 	 */
2229 
2230 	sk->sk_prot->unhash(sk);
2231 
2232 	/*
2233 	 * In this point socket cannot receive new packets, but it is possible
2234 	 * that some packets are in flight because some CPU runs receiver and
2235 	 * did hash table lookup before we unhashed socket. They will achieve
2236 	 * receive queue and will be purged by socket destructor.
2237 	 *
2238 	 * Also we still have packets pending on receive queue and probably,
2239 	 * our own packets waiting in device queues. sock_destroy will drain
2240 	 * receive queue, but transmitted packets will delay socket destruction
2241 	 * until the last reference will be released.
2242 	 */
2243 
2244 	sock_orphan(sk);
2245 
2246 	xfrm_sk_free_policy(sk);
2247 
2248 	sk_refcnt_debug_release(sk);
2249 	sock_put(sk);
2250 }
2251 EXPORT_SYMBOL(sk_common_release);
2252 
2253 static DEFINE_RWLOCK(proto_list_lock);
2254 static LIST_HEAD(proto_list);
2255 
2256 #ifdef CONFIG_PROC_FS
2257 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
2258 struct prot_inuse {
2259 	int val[PROTO_INUSE_NR];
2260 };
2261 
2262 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2263 
2264 #ifdef CONFIG_NET_NS
2265 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2266 {
2267 	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2268 }
2269 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2270 
2271 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2272 {
2273 	int cpu, idx = prot->inuse_idx;
2274 	int res = 0;
2275 
2276 	for_each_possible_cpu(cpu)
2277 		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2278 
2279 	return res >= 0 ? res : 0;
2280 }
2281 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2282 
2283 static int __net_init sock_inuse_init_net(struct net *net)
2284 {
2285 	net->core.inuse = alloc_percpu(struct prot_inuse);
2286 	return net->core.inuse ? 0 : -ENOMEM;
2287 }
2288 
2289 static void __net_exit sock_inuse_exit_net(struct net *net)
2290 {
2291 	free_percpu(net->core.inuse);
2292 }
2293 
2294 static struct pernet_operations net_inuse_ops = {
2295 	.init = sock_inuse_init_net,
2296 	.exit = sock_inuse_exit_net,
2297 };
2298 
2299 static __init int net_inuse_init(void)
2300 {
2301 	if (register_pernet_subsys(&net_inuse_ops))
2302 		panic("Cannot initialize net inuse counters");
2303 
2304 	return 0;
2305 }
2306 
2307 core_initcall(net_inuse_init);
2308 #else
2309 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2310 
2311 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2312 {
2313 	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2314 }
2315 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2316 
2317 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2318 {
2319 	int cpu, idx = prot->inuse_idx;
2320 	int res = 0;
2321 
2322 	for_each_possible_cpu(cpu)
2323 		res += per_cpu(prot_inuse, cpu).val[idx];
2324 
2325 	return res >= 0 ? res : 0;
2326 }
2327 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2328 #endif
2329 
2330 static void assign_proto_idx(struct proto *prot)
2331 {
2332 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2333 
2334 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2335 		printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2336 		return;
2337 	}
2338 
2339 	set_bit(prot->inuse_idx, proto_inuse_idx);
2340 }
2341 
2342 static void release_proto_idx(struct proto *prot)
2343 {
2344 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2345 		clear_bit(prot->inuse_idx, proto_inuse_idx);
2346 }
2347 #else
2348 static inline void assign_proto_idx(struct proto *prot)
2349 {
2350 }
2351 
2352 static inline void release_proto_idx(struct proto *prot)
2353 {
2354 }
2355 #endif
2356 
2357 int proto_register(struct proto *prot, int alloc_slab)
2358 {
2359 	if (alloc_slab) {
2360 		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2361 					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2362 					NULL);
2363 
2364 		if (prot->slab == NULL) {
2365 			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2366 			       prot->name);
2367 			goto out;
2368 		}
2369 
2370 		if (prot->rsk_prot != NULL) {
2371 			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2372 			if (prot->rsk_prot->slab_name == NULL)
2373 				goto out_free_sock_slab;
2374 
2375 			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2376 								 prot->rsk_prot->obj_size, 0,
2377 								 SLAB_HWCACHE_ALIGN, NULL);
2378 
2379 			if (prot->rsk_prot->slab == NULL) {
2380 				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2381 				       prot->name);
2382 				goto out_free_request_sock_slab_name;
2383 			}
2384 		}
2385 
2386 		if (prot->twsk_prot != NULL) {
2387 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2388 
2389 			if (prot->twsk_prot->twsk_slab_name == NULL)
2390 				goto out_free_request_sock_slab;
2391 
2392 			prot->twsk_prot->twsk_slab =
2393 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2394 						  prot->twsk_prot->twsk_obj_size,
2395 						  0,
2396 						  SLAB_HWCACHE_ALIGN |
2397 							prot->slab_flags,
2398 						  NULL);
2399 			if (prot->twsk_prot->twsk_slab == NULL)
2400 				goto out_free_timewait_sock_slab_name;
2401 		}
2402 	}
2403 
2404 	write_lock(&proto_list_lock);
2405 	list_add(&prot->node, &proto_list);
2406 	assign_proto_idx(prot);
2407 	write_unlock(&proto_list_lock);
2408 	return 0;
2409 
2410 out_free_timewait_sock_slab_name:
2411 	kfree(prot->twsk_prot->twsk_slab_name);
2412 out_free_request_sock_slab:
2413 	if (prot->rsk_prot && prot->rsk_prot->slab) {
2414 		kmem_cache_destroy(prot->rsk_prot->slab);
2415 		prot->rsk_prot->slab = NULL;
2416 	}
2417 out_free_request_sock_slab_name:
2418 	if (prot->rsk_prot)
2419 		kfree(prot->rsk_prot->slab_name);
2420 out_free_sock_slab:
2421 	kmem_cache_destroy(prot->slab);
2422 	prot->slab = NULL;
2423 out:
2424 	return -ENOBUFS;
2425 }
2426 EXPORT_SYMBOL(proto_register);
2427 
2428 void proto_unregister(struct proto *prot)
2429 {
2430 	write_lock(&proto_list_lock);
2431 	release_proto_idx(prot);
2432 	list_del(&prot->node);
2433 	write_unlock(&proto_list_lock);
2434 
2435 	if (prot->slab != NULL) {
2436 		kmem_cache_destroy(prot->slab);
2437 		prot->slab = NULL;
2438 	}
2439 
2440 	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2441 		kmem_cache_destroy(prot->rsk_prot->slab);
2442 		kfree(prot->rsk_prot->slab_name);
2443 		prot->rsk_prot->slab = NULL;
2444 	}
2445 
2446 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2447 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2448 		kfree(prot->twsk_prot->twsk_slab_name);
2449 		prot->twsk_prot->twsk_slab = NULL;
2450 	}
2451 }
2452 EXPORT_SYMBOL(proto_unregister);
2453 
2454 #ifdef CONFIG_PROC_FS
2455 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2456 	__acquires(proto_list_lock)
2457 {
2458 	read_lock(&proto_list_lock);
2459 	return seq_list_start_head(&proto_list, *pos);
2460 }
2461 
2462 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2463 {
2464 	return seq_list_next(v, &proto_list, pos);
2465 }
2466 
2467 static void proto_seq_stop(struct seq_file *seq, void *v)
2468 	__releases(proto_list_lock)
2469 {
2470 	read_unlock(&proto_list_lock);
2471 }
2472 
2473 static char proto_method_implemented(const void *method)
2474 {
2475 	return method == NULL ? 'n' : 'y';
2476 }
2477 
2478 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2479 {
2480 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2481 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2482 		   proto->name,
2483 		   proto->obj_size,
2484 		   sock_prot_inuse_get(seq_file_net(seq), proto),
2485 		   proto->memory_allocated != NULL ? atomic_long_read(proto->memory_allocated) : -1L,
2486 		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2487 		   proto->max_header,
2488 		   proto->slab == NULL ? "no" : "yes",
2489 		   module_name(proto->owner),
2490 		   proto_method_implemented(proto->close),
2491 		   proto_method_implemented(proto->connect),
2492 		   proto_method_implemented(proto->disconnect),
2493 		   proto_method_implemented(proto->accept),
2494 		   proto_method_implemented(proto->ioctl),
2495 		   proto_method_implemented(proto->init),
2496 		   proto_method_implemented(proto->destroy),
2497 		   proto_method_implemented(proto->shutdown),
2498 		   proto_method_implemented(proto->setsockopt),
2499 		   proto_method_implemented(proto->getsockopt),
2500 		   proto_method_implemented(proto->sendmsg),
2501 		   proto_method_implemented(proto->recvmsg),
2502 		   proto_method_implemented(proto->sendpage),
2503 		   proto_method_implemented(proto->bind),
2504 		   proto_method_implemented(proto->backlog_rcv),
2505 		   proto_method_implemented(proto->hash),
2506 		   proto_method_implemented(proto->unhash),
2507 		   proto_method_implemented(proto->get_port),
2508 		   proto_method_implemented(proto->enter_memory_pressure));
2509 }
2510 
2511 static int proto_seq_show(struct seq_file *seq, void *v)
2512 {
2513 	if (v == &proto_list)
2514 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2515 			   "protocol",
2516 			   "size",
2517 			   "sockets",
2518 			   "memory",
2519 			   "press",
2520 			   "maxhdr",
2521 			   "slab",
2522 			   "module",
2523 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2524 	else
2525 		proto_seq_printf(seq, list_entry(v, struct proto, node));
2526 	return 0;
2527 }
2528 
2529 static const struct seq_operations proto_seq_ops = {
2530 	.start  = proto_seq_start,
2531 	.next   = proto_seq_next,
2532 	.stop   = proto_seq_stop,
2533 	.show   = proto_seq_show,
2534 };
2535 
2536 static int proto_seq_open(struct inode *inode, struct file *file)
2537 {
2538 	return seq_open_net(inode, file, &proto_seq_ops,
2539 			    sizeof(struct seq_net_private));
2540 }
2541 
2542 static const struct file_operations proto_seq_fops = {
2543 	.owner		= THIS_MODULE,
2544 	.open		= proto_seq_open,
2545 	.read		= seq_read,
2546 	.llseek		= seq_lseek,
2547 	.release	= seq_release_net,
2548 };
2549 
2550 static __net_init int proto_init_net(struct net *net)
2551 {
2552 	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2553 		return -ENOMEM;
2554 
2555 	return 0;
2556 }
2557 
2558 static __net_exit void proto_exit_net(struct net *net)
2559 {
2560 	proc_net_remove(net, "protocols");
2561 }
2562 
2563 
2564 static __net_initdata struct pernet_operations proto_net_ops = {
2565 	.init = proto_init_net,
2566 	.exit = proto_exit_net,
2567 };
2568 
2569 static int __init proto_init(void)
2570 {
2571 	return register_pernet_subsys(&proto_net_ops);
2572 }
2573 
2574 subsys_initcall(proto_init);
2575 
2576 #endif /* PROC_FS */
2577