xref: /openbmc/linux/net/core/sock.c (revision 75f25bd3)
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	(sizeof(struct sk_buff) + 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_assign_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 		if (valbool)
742 			sock_set_flag(sk, SOCK_RXQ_OVFL);
743 		else
744 			sock_reset_flag(sk, SOCK_RXQ_OVFL);
745 		break;
746 	default:
747 		ret = -ENOPROTOOPT;
748 		break;
749 	}
750 	release_sock(sk);
751 	return ret;
752 }
753 EXPORT_SYMBOL(sock_setsockopt);
754 
755 
756 void cred_to_ucred(struct pid *pid, const struct cred *cred,
757 		   struct ucred *ucred)
758 {
759 	ucred->pid = pid_vnr(pid);
760 	ucred->uid = ucred->gid = -1;
761 	if (cred) {
762 		struct user_namespace *current_ns = current_user_ns();
763 
764 		ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
765 		ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
766 	}
767 }
768 EXPORT_SYMBOL_GPL(cred_to_ucred);
769 
770 int sock_getsockopt(struct socket *sock, int level, int optname,
771 		    char __user *optval, int __user *optlen)
772 {
773 	struct sock *sk = sock->sk;
774 
775 	union {
776 		int val;
777 		struct linger ling;
778 		struct timeval tm;
779 	} v;
780 
781 	int lv = sizeof(int);
782 	int len;
783 
784 	if (get_user(len, optlen))
785 		return -EFAULT;
786 	if (len < 0)
787 		return -EINVAL;
788 
789 	memset(&v, 0, sizeof(v));
790 
791 	switch (optname) {
792 	case SO_DEBUG:
793 		v.val = sock_flag(sk, SOCK_DBG);
794 		break;
795 
796 	case SO_DONTROUTE:
797 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
798 		break;
799 
800 	case SO_BROADCAST:
801 		v.val = !!sock_flag(sk, SOCK_BROADCAST);
802 		break;
803 
804 	case SO_SNDBUF:
805 		v.val = sk->sk_sndbuf;
806 		break;
807 
808 	case SO_RCVBUF:
809 		v.val = sk->sk_rcvbuf;
810 		break;
811 
812 	case SO_REUSEADDR:
813 		v.val = sk->sk_reuse;
814 		break;
815 
816 	case SO_KEEPALIVE:
817 		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
818 		break;
819 
820 	case SO_TYPE:
821 		v.val = sk->sk_type;
822 		break;
823 
824 	case SO_PROTOCOL:
825 		v.val = sk->sk_protocol;
826 		break;
827 
828 	case SO_DOMAIN:
829 		v.val = sk->sk_family;
830 		break;
831 
832 	case SO_ERROR:
833 		v.val = -sock_error(sk);
834 		if (v.val == 0)
835 			v.val = xchg(&sk->sk_err_soft, 0);
836 		break;
837 
838 	case SO_OOBINLINE:
839 		v.val = !!sock_flag(sk, SOCK_URGINLINE);
840 		break;
841 
842 	case SO_NO_CHECK:
843 		v.val = sk->sk_no_check;
844 		break;
845 
846 	case SO_PRIORITY:
847 		v.val = sk->sk_priority;
848 		break;
849 
850 	case SO_LINGER:
851 		lv		= sizeof(v.ling);
852 		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
853 		v.ling.l_linger	= sk->sk_lingertime / HZ;
854 		break;
855 
856 	case SO_BSDCOMPAT:
857 		sock_warn_obsolete_bsdism("getsockopt");
858 		break;
859 
860 	case SO_TIMESTAMP:
861 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
862 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
863 		break;
864 
865 	case SO_TIMESTAMPNS:
866 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
867 		break;
868 
869 	case SO_TIMESTAMPING:
870 		v.val = 0;
871 		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
872 			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
873 		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
874 			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
875 		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
876 			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
877 		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
878 			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
879 		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
880 			v.val |= SOF_TIMESTAMPING_SOFTWARE;
881 		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
882 			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
883 		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
884 			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
885 		break;
886 
887 	case SO_RCVTIMEO:
888 		lv = sizeof(struct timeval);
889 		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
890 			v.tm.tv_sec = 0;
891 			v.tm.tv_usec = 0;
892 		} else {
893 			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
894 			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
895 		}
896 		break;
897 
898 	case SO_SNDTIMEO:
899 		lv = sizeof(struct timeval);
900 		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
901 			v.tm.tv_sec = 0;
902 			v.tm.tv_usec = 0;
903 		} else {
904 			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
905 			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
906 		}
907 		break;
908 
909 	case SO_RCVLOWAT:
910 		v.val = sk->sk_rcvlowat;
911 		break;
912 
913 	case SO_SNDLOWAT:
914 		v.val = 1;
915 		break;
916 
917 	case SO_PASSCRED:
918 		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
919 		break;
920 
921 	case SO_PEERCRED:
922 	{
923 		struct ucred peercred;
924 		if (len > sizeof(peercred))
925 			len = sizeof(peercred);
926 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
927 		if (copy_to_user(optval, &peercred, len))
928 			return -EFAULT;
929 		goto lenout;
930 	}
931 
932 	case SO_PEERNAME:
933 	{
934 		char address[128];
935 
936 		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
937 			return -ENOTCONN;
938 		if (lv < len)
939 			return -EINVAL;
940 		if (copy_to_user(optval, address, len))
941 			return -EFAULT;
942 		goto lenout;
943 	}
944 
945 	/* Dubious BSD thing... Probably nobody even uses it, but
946 	 * the UNIX standard wants it for whatever reason... -DaveM
947 	 */
948 	case SO_ACCEPTCONN:
949 		v.val = sk->sk_state == TCP_LISTEN;
950 		break;
951 
952 	case SO_PASSSEC:
953 		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
954 		break;
955 
956 	case SO_PEERSEC:
957 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
958 
959 	case SO_MARK:
960 		v.val = sk->sk_mark;
961 		break;
962 
963 	case SO_RXQ_OVFL:
964 		v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
965 		break;
966 
967 	default:
968 		return -ENOPROTOOPT;
969 	}
970 
971 	if (len > lv)
972 		len = lv;
973 	if (copy_to_user(optval, &v, len))
974 		return -EFAULT;
975 lenout:
976 	if (put_user(len, optlen))
977 		return -EFAULT;
978 	return 0;
979 }
980 
981 /*
982  * Initialize an sk_lock.
983  *
984  * (We also register the sk_lock with the lock validator.)
985  */
986 static inline void sock_lock_init(struct sock *sk)
987 {
988 	sock_lock_init_class_and_name(sk,
989 			af_family_slock_key_strings[sk->sk_family],
990 			af_family_slock_keys + sk->sk_family,
991 			af_family_key_strings[sk->sk_family],
992 			af_family_keys + sk->sk_family);
993 }
994 
995 /*
996  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
997  * even temporarly, because of RCU lookups. sk_node should also be left as is.
998  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
999  */
1000 static void sock_copy(struct sock *nsk, const struct sock *osk)
1001 {
1002 #ifdef CONFIG_SECURITY_NETWORK
1003 	void *sptr = nsk->sk_security;
1004 #endif
1005 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1006 
1007 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1008 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1009 
1010 #ifdef CONFIG_SECURITY_NETWORK
1011 	nsk->sk_security = sptr;
1012 	security_sk_clone(osk, nsk);
1013 #endif
1014 }
1015 
1016 /*
1017  * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1018  * un-modified. Special care is taken when initializing object to zero.
1019  */
1020 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1021 {
1022 	if (offsetof(struct sock, sk_node.next) != 0)
1023 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1024 	memset(&sk->sk_node.pprev, 0,
1025 	       size - offsetof(struct sock, sk_node.pprev));
1026 }
1027 
1028 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1029 {
1030 	unsigned long nulls1, nulls2;
1031 
1032 	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1033 	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1034 	if (nulls1 > nulls2)
1035 		swap(nulls1, nulls2);
1036 
1037 	if (nulls1 != 0)
1038 		memset((char *)sk, 0, nulls1);
1039 	memset((char *)sk + nulls1 + sizeof(void *), 0,
1040 	       nulls2 - nulls1 - sizeof(void *));
1041 	memset((char *)sk + nulls2 + sizeof(void *), 0,
1042 	       size - nulls2 - sizeof(void *));
1043 }
1044 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1045 
1046 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1047 		int family)
1048 {
1049 	struct sock *sk;
1050 	struct kmem_cache *slab;
1051 
1052 	slab = prot->slab;
1053 	if (slab != NULL) {
1054 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1055 		if (!sk)
1056 			return sk;
1057 		if (priority & __GFP_ZERO) {
1058 			if (prot->clear_sk)
1059 				prot->clear_sk(sk, prot->obj_size);
1060 			else
1061 				sk_prot_clear_nulls(sk, prot->obj_size);
1062 		}
1063 	} else
1064 		sk = kmalloc(prot->obj_size, priority);
1065 
1066 	if (sk != NULL) {
1067 		kmemcheck_annotate_bitfield(sk, flags);
1068 
1069 		if (security_sk_alloc(sk, family, priority))
1070 			goto out_free;
1071 
1072 		if (!try_module_get(prot->owner))
1073 			goto out_free_sec;
1074 		sk_tx_queue_clear(sk);
1075 	}
1076 
1077 	return sk;
1078 
1079 out_free_sec:
1080 	security_sk_free(sk);
1081 out_free:
1082 	if (slab != NULL)
1083 		kmem_cache_free(slab, sk);
1084 	else
1085 		kfree(sk);
1086 	return NULL;
1087 }
1088 
1089 static void sk_prot_free(struct proto *prot, struct sock *sk)
1090 {
1091 	struct kmem_cache *slab;
1092 	struct module *owner;
1093 
1094 	owner = prot->owner;
1095 	slab = prot->slab;
1096 
1097 	security_sk_free(sk);
1098 	if (slab != NULL)
1099 		kmem_cache_free(slab, sk);
1100 	else
1101 		kfree(sk);
1102 	module_put(owner);
1103 }
1104 
1105 #ifdef CONFIG_CGROUPS
1106 void sock_update_classid(struct sock *sk)
1107 {
1108 	u32 classid;
1109 
1110 	rcu_read_lock();  /* doing current task, which cannot vanish. */
1111 	classid = task_cls_classid(current);
1112 	rcu_read_unlock();
1113 	if (classid && classid != sk->sk_classid)
1114 		sk->sk_classid = classid;
1115 }
1116 EXPORT_SYMBOL(sock_update_classid);
1117 #endif
1118 
1119 /**
1120  *	sk_alloc - All socket objects are allocated here
1121  *	@net: the applicable net namespace
1122  *	@family: protocol family
1123  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1124  *	@prot: struct proto associated with this new sock instance
1125  */
1126 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1127 		      struct proto *prot)
1128 {
1129 	struct sock *sk;
1130 
1131 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1132 	if (sk) {
1133 		sk->sk_family = family;
1134 		/*
1135 		 * See comment in struct sock definition to understand
1136 		 * why we need sk_prot_creator -acme
1137 		 */
1138 		sk->sk_prot = sk->sk_prot_creator = prot;
1139 		sock_lock_init(sk);
1140 		sock_net_set(sk, get_net(net));
1141 		atomic_set(&sk->sk_wmem_alloc, 1);
1142 
1143 		sock_update_classid(sk);
1144 	}
1145 
1146 	return sk;
1147 }
1148 EXPORT_SYMBOL(sk_alloc);
1149 
1150 static void __sk_free(struct sock *sk)
1151 {
1152 	struct sk_filter *filter;
1153 
1154 	if (sk->sk_destruct)
1155 		sk->sk_destruct(sk);
1156 
1157 	filter = rcu_dereference_check(sk->sk_filter,
1158 				       atomic_read(&sk->sk_wmem_alloc) == 0);
1159 	if (filter) {
1160 		sk_filter_uncharge(sk, filter);
1161 		rcu_assign_pointer(sk->sk_filter, NULL);
1162 	}
1163 
1164 	sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1165 	sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1166 
1167 	if (atomic_read(&sk->sk_omem_alloc))
1168 		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1169 		       __func__, atomic_read(&sk->sk_omem_alloc));
1170 
1171 	if (sk->sk_peer_cred)
1172 		put_cred(sk->sk_peer_cred);
1173 	put_pid(sk->sk_peer_pid);
1174 	put_net(sock_net(sk));
1175 	sk_prot_free(sk->sk_prot_creator, sk);
1176 }
1177 
1178 void sk_free(struct sock *sk)
1179 {
1180 	/*
1181 	 * We subtract one from sk_wmem_alloc and can know if
1182 	 * some packets are still in some tx queue.
1183 	 * If not null, sock_wfree() will call __sk_free(sk) later
1184 	 */
1185 	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1186 		__sk_free(sk);
1187 }
1188 EXPORT_SYMBOL(sk_free);
1189 
1190 /*
1191  * Last sock_put should drop reference to sk->sk_net. It has already
1192  * been dropped in sk_change_net. Taking reference to stopping namespace
1193  * is not an option.
1194  * Take reference to a socket to remove it from hash _alive_ and after that
1195  * destroy it in the context of init_net.
1196  */
1197 void sk_release_kernel(struct sock *sk)
1198 {
1199 	if (sk == NULL || sk->sk_socket == NULL)
1200 		return;
1201 
1202 	sock_hold(sk);
1203 	sock_release(sk->sk_socket);
1204 	release_net(sock_net(sk));
1205 	sock_net_set(sk, get_net(&init_net));
1206 	sock_put(sk);
1207 }
1208 EXPORT_SYMBOL(sk_release_kernel);
1209 
1210 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1211 {
1212 	struct sock *newsk;
1213 
1214 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1215 	if (newsk != NULL) {
1216 		struct sk_filter *filter;
1217 
1218 		sock_copy(newsk, sk);
1219 
1220 		/* SANITY */
1221 		get_net(sock_net(newsk));
1222 		sk_node_init(&newsk->sk_node);
1223 		sock_lock_init(newsk);
1224 		bh_lock_sock(newsk);
1225 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1226 		newsk->sk_backlog.len = 0;
1227 
1228 		atomic_set(&newsk->sk_rmem_alloc, 0);
1229 		/*
1230 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1231 		 */
1232 		atomic_set(&newsk->sk_wmem_alloc, 1);
1233 		atomic_set(&newsk->sk_omem_alloc, 0);
1234 		skb_queue_head_init(&newsk->sk_receive_queue);
1235 		skb_queue_head_init(&newsk->sk_write_queue);
1236 #ifdef CONFIG_NET_DMA
1237 		skb_queue_head_init(&newsk->sk_async_wait_queue);
1238 #endif
1239 
1240 		spin_lock_init(&newsk->sk_dst_lock);
1241 		rwlock_init(&newsk->sk_callback_lock);
1242 		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1243 				af_callback_keys + newsk->sk_family,
1244 				af_family_clock_key_strings[newsk->sk_family]);
1245 
1246 		newsk->sk_dst_cache	= NULL;
1247 		newsk->sk_wmem_queued	= 0;
1248 		newsk->sk_forward_alloc = 0;
1249 		newsk->sk_send_head	= NULL;
1250 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1251 
1252 		sock_reset_flag(newsk, SOCK_DONE);
1253 		skb_queue_head_init(&newsk->sk_error_queue);
1254 
1255 		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1256 		if (filter != NULL)
1257 			sk_filter_charge(newsk, filter);
1258 
1259 		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1260 			/* It is still raw copy of parent, so invalidate
1261 			 * destructor and make plain sk_free() */
1262 			newsk->sk_destruct = NULL;
1263 			sk_free(newsk);
1264 			newsk = NULL;
1265 			goto out;
1266 		}
1267 
1268 		newsk->sk_err	   = 0;
1269 		newsk->sk_priority = 0;
1270 		/*
1271 		 * Before updating sk_refcnt, we must commit prior changes to memory
1272 		 * (Documentation/RCU/rculist_nulls.txt for details)
1273 		 */
1274 		smp_wmb();
1275 		atomic_set(&newsk->sk_refcnt, 2);
1276 
1277 		/*
1278 		 * Increment the counter in the same struct proto as the master
1279 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1280 		 * is the same as sk->sk_prot->socks, as this field was copied
1281 		 * with memcpy).
1282 		 *
1283 		 * This _changes_ the previous behaviour, where
1284 		 * tcp_create_openreq_child always was incrementing the
1285 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1286 		 * to be taken into account in all callers. -acme
1287 		 */
1288 		sk_refcnt_debug_inc(newsk);
1289 		sk_set_socket(newsk, NULL);
1290 		newsk->sk_wq = NULL;
1291 
1292 		if (newsk->sk_prot->sockets_allocated)
1293 			percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1294 
1295 		if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1296 		    sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1297 			net_enable_timestamp();
1298 	}
1299 out:
1300 	return newsk;
1301 }
1302 EXPORT_SYMBOL_GPL(sk_clone);
1303 
1304 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1305 {
1306 	__sk_dst_set(sk, dst);
1307 	sk->sk_route_caps = dst->dev->features;
1308 	if (sk->sk_route_caps & NETIF_F_GSO)
1309 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1310 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1311 	if (sk_can_gso(sk)) {
1312 		if (dst->header_len) {
1313 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1314 		} else {
1315 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1316 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1317 		}
1318 	}
1319 }
1320 EXPORT_SYMBOL_GPL(sk_setup_caps);
1321 
1322 void __init sk_init(void)
1323 {
1324 	if (totalram_pages <= 4096) {
1325 		sysctl_wmem_max = 32767;
1326 		sysctl_rmem_max = 32767;
1327 		sysctl_wmem_default = 32767;
1328 		sysctl_rmem_default = 32767;
1329 	} else if (totalram_pages >= 131072) {
1330 		sysctl_wmem_max = 131071;
1331 		sysctl_rmem_max = 131071;
1332 	}
1333 }
1334 
1335 /*
1336  *	Simple resource managers for sockets.
1337  */
1338 
1339 
1340 /*
1341  * Write buffer destructor automatically called from kfree_skb.
1342  */
1343 void sock_wfree(struct sk_buff *skb)
1344 {
1345 	struct sock *sk = skb->sk;
1346 	unsigned int len = skb->truesize;
1347 
1348 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1349 		/*
1350 		 * Keep a reference on sk_wmem_alloc, this will be released
1351 		 * after sk_write_space() call
1352 		 */
1353 		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1354 		sk->sk_write_space(sk);
1355 		len = 1;
1356 	}
1357 	/*
1358 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1359 	 * could not do because of in-flight packets
1360 	 */
1361 	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1362 		__sk_free(sk);
1363 }
1364 EXPORT_SYMBOL(sock_wfree);
1365 
1366 /*
1367  * Read buffer destructor automatically called from kfree_skb.
1368  */
1369 void sock_rfree(struct sk_buff *skb)
1370 {
1371 	struct sock *sk = skb->sk;
1372 	unsigned int len = skb->truesize;
1373 
1374 	atomic_sub(len, &sk->sk_rmem_alloc);
1375 	sk_mem_uncharge(sk, len);
1376 }
1377 EXPORT_SYMBOL(sock_rfree);
1378 
1379 
1380 int sock_i_uid(struct sock *sk)
1381 {
1382 	int uid;
1383 
1384 	read_lock_bh(&sk->sk_callback_lock);
1385 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1386 	read_unlock_bh(&sk->sk_callback_lock);
1387 	return uid;
1388 }
1389 EXPORT_SYMBOL(sock_i_uid);
1390 
1391 unsigned long sock_i_ino(struct sock *sk)
1392 {
1393 	unsigned long ino;
1394 
1395 	read_lock_bh(&sk->sk_callback_lock);
1396 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1397 	read_unlock_bh(&sk->sk_callback_lock);
1398 	return ino;
1399 }
1400 EXPORT_SYMBOL(sock_i_ino);
1401 
1402 /*
1403  * Allocate a skb from the socket's send buffer.
1404  */
1405 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1406 			     gfp_t priority)
1407 {
1408 	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1409 		struct sk_buff *skb = alloc_skb(size, priority);
1410 		if (skb) {
1411 			skb_set_owner_w(skb, sk);
1412 			return skb;
1413 		}
1414 	}
1415 	return NULL;
1416 }
1417 EXPORT_SYMBOL(sock_wmalloc);
1418 
1419 /*
1420  * Allocate a skb from the socket's receive buffer.
1421  */
1422 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1423 			     gfp_t priority)
1424 {
1425 	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1426 		struct sk_buff *skb = alloc_skb(size, priority);
1427 		if (skb) {
1428 			skb_set_owner_r(skb, sk);
1429 			return skb;
1430 		}
1431 	}
1432 	return NULL;
1433 }
1434 
1435 /*
1436  * Allocate a memory block from the socket's option memory buffer.
1437  */
1438 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1439 {
1440 	if ((unsigned)size <= sysctl_optmem_max &&
1441 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1442 		void *mem;
1443 		/* First do the add, to avoid the race if kmalloc
1444 		 * might sleep.
1445 		 */
1446 		atomic_add(size, &sk->sk_omem_alloc);
1447 		mem = kmalloc(size, priority);
1448 		if (mem)
1449 			return mem;
1450 		atomic_sub(size, &sk->sk_omem_alloc);
1451 	}
1452 	return NULL;
1453 }
1454 EXPORT_SYMBOL(sock_kmalloc);
1455 
1456 /*
1457  * Free an option memory block.
1458  */
1459 void sock_kfree_s(struct sock *sk, void *mem, int size)
1460 {
1461 	kfree(mem);
1462 	atomic_sub(size, &sk->sk_omem_alloc);
1463 }
1464 EXPORT_SYMBOL(sock_kfree_s);
1465 
1466 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1467    I think, these locks should be removed for datagram sockets.
1468  */
1469 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1470 {
1471 	DEFINE_WAIT(wait);
1472 
1473 	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1474 	for (;;) {
1475 		if (!timeo)
1476 			break;
1477 		if (signal_pending(current))
1478 			break;
1479 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1480 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1481 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1482 			break;
1483 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1484 			break;
1485 		if (sk->sk_err)
1486 			break;
1487 		timeo = schedule_timeout(timeo);
1488 	}
1489 	finish_wait(sk_sleep(sk), &wait);
1490 	return timeo;
1491 }
1492 
1493 
1494 /*
1495  *	Generic send/receive buffer handlers
1496  */
1497 
1498 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1499 				     unsigned long data_len, int noblock,
1500 				     int *errcode)
1501 {
1502 	struct sk_buff *skb;
1503 	gfp_t gfp_mask;
1504 	long timeo;
1505 	int err;
1506 
1507 	gfp_mask = sk->sk_allocation;
1508 	if (gfp_mask & __GFP_WAIT)
1509 		gfp_mask |= __GFP_REPEAT;
1510 
1511 	timeo = sock_sndtimeo(sk, noblock);
1512 	while (1) {
1513 		err = sock_error(sk);
1514 		if (err != 0)
1515 			goto failure;
1516 
1517 		err = -EPIPE;
1518 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1519 			goto failure;
1520 
1521 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1522 			skb = alloc_skb(header_len, gfp_mask);
1523 			if (skb) {
1524 				int npages;
1525 				int i;
1526 
1527 				/* No pages, we're done... */
1528 				if (!data_len)
1529 					break;
1530 
1531 				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1532 				skb->truesize += data_len;
1533 				skb_shinfo(skb)->nr_frags = npages;
1534 				for (i = 0; i < npages; i++) {
1535 					struct page *page;
1536 					skb_frag_t *frag;
1537 
1538 					page = alloc_pages(sk->sk_allocation, 0);
1539 					if (!page) {
1540 						err = -ENOBUFS;
1541 						skb_shinfo(skb)->nr_frags = i;
1542 						kfree_skb(skb);
1543 						goto failure;
1544 					}
1545 
1546 					frag = &skb_shinfo(skb)->frags[i];
1547 					frag->page = page;
1548 					frag->page_offset = 0;
1549 					frag->size = (data_len >= PAGE_SIZE ?
1550 						      PAGE_SIZE :
1551 						      data_len);
1552 					data_len -= PAGE_SIZE;
1553 				}
1554 
1555 				/* Full success... */
1556 				break;
1557 			}
1558 			err = -ENOBUFS;
1559 			goto failure;
1560 		}
1561 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1562 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1563 		err = -EAGAIN;
1564 		if (!timeo)
1565 			goto failure;
1566 		if (signal_pending(current))
1567 			goto interrupted;
1568 		timeo = sock_wait_for_wmem(sk, timeo);
1569 	}
1570 
1571 	skb_set_owner_w(skb, sk);
1572 	return skb;
1573 
1574 interrupted:
1575 	err = sock_intr_errno(timeo);
1576 failure:
1577 	*errcode = err;
1578 	return NULL;
1579 }
1580 EXPORT_SYMBOL(sock_alloc_send_pskb);
1581 
1582 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1583 				    int noblock, int *errcode)
1584 {
1585 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1586 }
1587 EXPORT_SYMBOL(sock_alloc_send_skb);
1588 
1589 static void __lock_sock(struct sock *sk)
1590 	__releases(&sk->sk_lock.slock)
1591 	__acquires(&sk->sk_lock.slock)
1592 {
1593 	DEFINE_WAIT(wait);
1594 
1595 	for (;;) {
1596 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1597 					TASK_UNINTERRUPTIBLE);
1598 		spin_unlock_bh(&sk->sk_lock.slock);
1599 		schedule();
1600 		spin_lock_bh(&sk->sk_lock.slock);
1601 		if (!sock_owned_by_user(sk))
1602 			break;
1603 	}
1604 	finish_wait(&sk->sk_lock.wq, &wait);
1605 }
1606 
1607 static void __release_sock(struct sock *sk)
1608 	__releases(&sk->sk_lock.slock)
1609 	__acquires(&sk->sk_lock.slock)
1610 {
1611 	struct sk_buff *skb = sk->sk_backlog.head;
1612 
1613 	do {
1614 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1615 		bh_unlock_sock(sk);
1616 
1617 		do {
1618 			struct sk_buff *next = skb->next;
1619 
1620 			WARN_ON_ONCE(skb_dst_is_noref(skb));
1621 			skb->next = NULL;
1622 			sk_backlog_rcv(sk, skb);
1623 
1624 			/*
1625 			 * We are in process context here with softirqs
1626 			 * disabled, use cond_resched_softirq() to preempt.
1627 			 * This is safe to do because we've taken the backlog
1628 			 * queue private:
1629 			 */
1630 			cond_resched_softirq();
1631 
1632 			skb = next;
1633 		} while (skb != NULL);
1634 
1635 		bh_lock_sock(sk);
1636 	} while ((skb = sk->sk_backlog.head) != NULL);
1637 
1638 	/*
1639 	 * Doing the zeroing here guarantee we can not loop forever
1640 	 * while a wild producer attempts to flood us.
1641 	 */
1642 	sk->sk_backlog.len = 0;
1643 }
1644 
1645 /**
1646  * sk_wait_data - wait for data to arrive at sk_receive_queue
1647  * @sk:    sock to wait on
1648  * @timeo: for how long
1649  *
1650  * Now socket state including sk->sk_err is changed only under lock,
1651  * hence we may omit checks after joining wait queue.
1652  * We check receive queue before schedule() only as optimization;
1653  * it is very likely that release_sock() added new data.
1654  */
1655 int sk_wait_data(struct sock *sk, long *timeo)
1656 {
1657 	int rc;
1658 	DEFINE_WAIT(wait);
1659 
1660 	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1661 	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1662 	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1663 	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1664 	finish_wait(sk_sleep(sk), &wait);
1665 	return rc;
1666 }
1667 EXPORT_SYMBOL(sk_wait_data);
1668 
1669 /**
1670  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1671  *	@sk: socket
1672  *	@size: memory size to allocate
1673  *	@kind: allocation type
1674  *
1675  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1676  *	rmem allocation. This function assumes that protocols which have
1677  *	memory_pressure use sk_wmem_queued as write buffer accounting.
1678  */
1679 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1680 {
1681 	struct proto *prot = sk->sk_prot;
1682 	int amt = sk_mem_pages(size);
1683 	long allocated;
1684 
1685 	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1686 	allocated = atomic_long_add_return(amt, prot->memory_allocated);
1687 
1688 	/* Under limit. */
1689 	if (allocated <= prot->sysctl_mem[0]) {
1690 		if (prot->memory_pressure && *prot->memory_pressure)
1691 			*prot->memory_pressure = 0;
1692 		return 1;
1693 	}
1694 
1695 	/* Under pressure. */
1696 	if (allocated > prot->sysctl_mem[1])
1697 		if (prot->enter_memory_pressure)
1698 			prot->enter_memory_pressure(sk);
1699 
1700 	/* Over hard limit. */
1701 	if (allocated > prot->sysctl_mem[2])
1702 		goto suppress_allocation;
1703 
1704 	/* guarantee minimum buffer size under pressure */
1705 	if (kind == SK_MEM_RECV) {
1706 		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1707 			return 1;
1708 	} else { /* SK_MEM_SEND */
1709 		if (sk->sk_type == SOCK_STREAM) {
1710 			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1711 				return 1;
1712 		} else if (atomic_read(&sk->sk_wmem_alloc) <
1713 			   prot->sysctl_wmem[0])
1714 				return 1;
1715 	}
1716 
1717 	if (prot->memory_pressure) {
1718 		int alloc;
1719 
1720 		if (!*prot->memory_pressure)
1721 			return 1;
1722 		alloc = percpu_counter_read_positive(prot->sockets_allocated);
1723 		if (prot->sysctl_mem[2] > alloc *
1724 		    sk_mem_pages(sk->sk_wmem_queued +
1725 				 atomic_read(&sk->sk_rmem_alloc) +
1726 				 sk->sk_forward_alloc))
1727 			return 1;
1728 	}
1729 
1730 suppress_allocation:
1731 
1732 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1733 		sk_stream_moderate_sndbuf(sk);
1734 
1735 		/* Fail only if socket is _under_ its sndbuf.
1736 		 * In this case we cannot block, so that we have to fail.
1737 		 */
1738 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1739 			return 1;
1740 	}
1741 
1742 	trace_sock_exceed_buf_limit(sk, prot, allocated);
1743 
1744 	/* Alas. Undo changes. */
1745 	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1746 	atomic_long_sub(amt, prot->memory_allocated);
1747 	return 0;
1748 }
1749 EXPORT_SYMBOL(__sk_mem_schedule);
1750 
1751 /**
1752  *	__sk_reclaim - reclaim memory_allocated
1753  *	@sk: socket
1754  */
1755 void __sk_mem_reclaim(struct sock *sk)
1756 {
1757 	struct proto *prot = sk->sk_prot;
1758 
1759 	atomic_long_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1760 		   prot->memory_allocated);
1761 	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1762 
1763 	if (prot->memory_pressure && *prot->memory_pressure &&
1764 	    (atomic_long_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1765 		*prot->memory_pressure = 0;
1766 }
1767 EXPORT_SYMBOL(__sk_mem_reclaim);
1768 
1769 
1770 /*
1771  * Set of default routines for initialising struct proto_ops when
1772  * the protocol does not support a particular function. In certain
1773  * cases where it makes no sense for a protocol to have a "do nothing"
1774  * function, some default processing is provided.
1775  */
1776 
1777 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1778 {
1779 	return -EOPNOTSUPP;
1780 }
1781 EXPORT_SYMBOL(sock_no_bind);
1782 
1783 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1784 		    int len, int flags)
1785 {
1786 	return -EOPNOTSUPP;
1787 }
1788 EXPORT_SYMBOL(sock_no_connect);
1789 
1790 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1791 {
1792 	return -EOPNOTSUPP;
1793 }
1794 EXPORT_SYMBOL(sock_no_socketpair);
1795 
1796 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1797 {
1798 	return -EOPNOTSUPP;
1799 }
1800 EXPORT_SYMBOL(sock_no_accept);
1801 
1802 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1803 		    int *len, int peer)
1804 {
1805 	return -EOPNOTSUPP;
1806 }
1807 EXPORT_SYMBOL(sock_no_getname);
1808 
1809 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1810 {
1811 	return 0;
1812 }
1813 EXPORT_SYMBOL(sock_no_poll);
1814 
1815 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1816 {
1817 	return -EOPNOTSUPP;
1818 }
1819 EXPORT_SYMBOL(sock_no_ioctl);
1820 
1821 int sock_no_listen(struct socket *sock, int backlog)
1822 {
1823 	return -EOPNOTSUPP;
1824 }
1825 EXPORT_SYMBOL(sock_no_listen);
1826 
1827 int sock_no_shutdown(struct socket *sock, int how)
1828 {
1829 	return -EOPNOTSUPP;
1830 }
1831 EXPORT_SYMBOL(sock_no_shutdown);
1832 
1833 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1834 		    char __user *optval, unsigned int optlen)
1835 {
1836 	return -EOPNOTSUPP;
1837 }
1838 EXPORT_SYMBOL(sock_no_setsockopt);
1839 
1840 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1841 		    char __user *optval, int __user *optlen)
1842 {
1843 	return -EOPNOTSUPP;
1844 }
1845 EXPORT_SYMBOL(sock_no_getsockopt);
1846 
1847 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1848 		    size_t len)
1849 {
1850 	return -EOPNOTSUPP;
1851 }
1852 EXPORT_SYMBOL(sock_no_sendmsg);
1853 
1854 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1855 		    size_t len, int flags)
1856 {
1857 	return -EOPNOTSUPP;
1858 }
1859 EXPORT_SYMBOL(sock_no_recvmsg);
1860 
1861 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1862 {
1863 	/* Mirror missing mmap method error code */
1864 	return -ENODEV;
1865 }
1866 EXPORT_SYMBOL(sock_no_mmap);
1867 
1868 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1869 {
1870 	ssize_t res;
1871 	struct msghdr msg = {.msg_flags = flags};
1872 	struct kvec iov;
1873 	char *kaddr = kmap(page);
1874 	iov.iov_base = kaddr + offset;
1875 	iov.iov_len = size;
1876 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1877 	kunmap(page);
1878 	return res;
1879 }
1880 EXPORT_SYMBOL(sock_no_sendpage);
1881 
1882 /*
1883  *	Default Socket Callbacks
1884  */
1885 
1886 static void sock_def_wakeup(struct sock *sk)
1887 {
1888 	struct socket_wq *wq;
1889 
1890 	rcu_read_lock();
1891 	wq = rcu_dereference(sk->sk_wq);
1892 	if (wq_has_sleeper(wq))
1893 		wake_up_interruptible_all(&wq->wait);
1894 	rcu_read_unlock();
1895 }
1896 
1897 static void sock_def_error_report(struct sock *sk)
1898 {
1899 	struct socket_wq *wq;
1900 
1901 	rcu_read_lock();
1902 	wq = rcu_dereference(sk->sk_wq);
1903 	if (wq_has_sleeper(wq))
1904 		wake_up_interruptible_poll(&wq->wait, POLLERR);
1905 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1906 	rcu_read_unlock();
1907 }
1908 
1909 static void sock_def_readable(struct sock *sk, int len)
1910 {
1911 	struct socket_wq *wq;
1912 
1913 	rcu_read_lock();
1914 	wq = rcu_dereference(sk->sk_wq);
1915 	if (wq_has_sleeper(wq))
1916 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
1917 						POLLRDNORM | POLLRDBAND);
1918 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1919 	rcu_read_unlock();
1920 }
1921 
1922 static void sock_def_write_space(struct sock *sk)
1923 {
1924 	struct socket_wq *wq;
1925 
1926 	rcu_read_lock();
1927 
1928 	/* Do not wake up a writer until he can make "significant"
1929 	 * progress.  --DaveM
1930 	 */
1931 	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1932 		wq = rcu_dereference(sk->sk_wq);
1933 		if (wq_has_sleeper(wq))
1934 			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1935 						POLLWRNORM | POLLWRBAND);
1936 
1937 		/* Should agree with poll, otherwise some programs break */
1938 		if (sock_writeable(sk))
1939 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1940 	}
1941 
1942 	rcu_read_unlock();
1943 }
1944 
1945 static void sock_def_destruct(struct sock *sk)
1946 {
1947 	kfree(sk->sk_protinfo);
1948 }
1949 
1950 void sk_send_sigurg(struct sock *sk)
1951 {
1952 	if (sk->sk_socket && sk->sk_socket->file)
1953 		if (send_sigurg(&sk->sk_socket->file->f_owner))
1954 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1955 }
1956 EXPORT_SYMBOL(sk_send_sigurg);
1957 
1958 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1959 		    unsigned long expires)
1960 {
1961 	if (!mod_timer(timer, expires))
1962 		sock_hold(sk);
1963 }
1964 EXPORT_SYMBOL(sk_reset_timer);
1965 
1966 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1967 {
1968 	if (timer_pending(timer) && del_timer(timer))
1969 		__sock_put(sk);
1970 }
1971 EXPORT_SYMBOL(sk_stop_timer);
1972 
1973 void sock_init_data(struct socket *sock, struct sock *sk)
1974 {
1975 	skb_queue_head_init(&sk->sk_receive_queue);
1976 	skb_queue_head_init(&sk->sk_write_queue);
1977 	skb_queue_head_init(&sk->sk_error_queue);
1978 #ifdef CONFIG_NET_DMA
1979 	skb_queue_head_init(&sk->sk_async_wait_queue);
1980 #endif
1981 
1982 	sk->sk_send_head	=	NULL;
1983 
1984 	init_timer(&sk->sk_timer);
1985 
1986 	sk->sk_allocation	=	GFP_KERNEL;
1987 	sk->sk_rcvbuf		=	sysctl_rmem_default;
1988 	sk->sk_sndbuf		=	sysctl_wmem_default;
1989 	sk->sk_state		=	TCP_CLOSE;
1990 	sk_set_socket(sk, sock);
1991 
1992 	sock_set_flag(sk, SOCK_ZAPPED);
1993 
1994 	if (sock) {
1995 		sk->sk_type	=	sock->type;
1996 		sk->sk_wq	=	sock->wq;
1997 		sock->sk	=	sk;
1998 	} else
1999 		sk->sk_wq	=	NULL;
2000 
2001 	spin_lock_init(&sk->sk_dst_lock);
2002 	rwlock_init(&sk->sk_callback_lock);
2003 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2004 			af_callback_keys + sk->sk_family,
2005 			af_family_clock_key_strings[sk->sk_family]);
2006 
2007 	sk->sk_state_change	=	sock_def_wakeup;
2008 	sk->sk_data_ready	=	sock_def_readable;
2009 	sk->sk_write_space	=	sock_def_write_space;
2010 	sk->sk_error_report	=	sock_def_error_report;
2011 	sk->sk_destruct		=	sock_def_destruct;
2012 
2013 	sk->sk_sndmsg_page	=	NULL;
2014 	sk->sk_sndmsg_off	=	0;
2015 
2016 	sk->sk_peer_pid 	=	NULL;
2017 	sk->sk_peer_cred	=	NULL;
2018 	sk->sk_write_pending	=	0;
2019 	sk->sk_rcvlowat		=	1;
2020 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2021 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2022 
2023 	sk->sk_stamp = ktime_set(-1L, 0);
2024 
2025 	/*
2026 	 * Before updating sk_refcnt, we must commit prior changes to memory
2027 	 * (Documentation/RCU/rculist_nulls.txt for details)
2028 	 */
2029 	smp_wmb();
2030 	atomic_set(&sk->sk_refcnt, 1);
2031 	atomic_set(&sk->sk_drops, 0);
2032 }
2033 EXPORT_SYMBOL(sock_init_data);
2034 
2035 void lock_sock_nested(struct sock *sk, int subclass)
2036 {
2037 	might_sleep();
2038 	spin_lock_bh(&sk->sk_lock.slock);
2039 	if (sk->sk_lock.owned)
2040 		__lock_sock(sk);
2041 	sk->sk_lock.owned = 1;
2042 	spin_unlock(&sk->sk_lock.slock);
2043 	/*
2044 	 * The sk_lock has mutex_lock() semantics here:
2045 	 */
2046 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2047 	local_bh_enable();
2048 }
2049 EXPORT_SYMBOL(lock_sock_nested);
2050 
2051 void release_sock(struct sock *sk)
2052 {
2053 	/*
2054 	 * The sk_lock has mutex_unlock() semantics:
2055 	 */
2056 	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2057 
2058 	spin_lock_bh(&sk->sk_lock.slock);
2059 	if (sk->sk_backlog.tail)
2060 		__release_sock(sk);
2061 	sk->sk_lock.owned = 0;
2062 	if (waitqueue_active(&sk->sk_lock.wq))
2063 		wake_up(&sk->sk_lock.wq);
2064 	spin_unlock_bh(&sk->sk_lock.slock);
2065 }
2066 EXPORT_SYMBOL(release_sock);
2067 
2068 /**
2069  * lock_sock_fast - fast version of lock_sock
2070  * @sk: socket
2071  *
2072  * This version should be used for very small section, where process wont block
2073  * return false if fast path is taken
2074  *   sk_lock.slock locked, owned = 0, BH disabled
2075  * return true if slow path is taken
2076  *   sk_lock.slock unlocked, owned = 1, BH enabled
2077  */
2078 bool lock_sock_fast(struct sock *sk)
2079 {
2080 	might_sleep();
2081 	spin_lock_bh(&sk->sk_lock.slock);
2082 
2083 	if (!sk->sk_lock.owned)
2084 		/*
2085 		 * Note : We must disable BH
2086 		 */
2087 		return false;
2088 
2089 	__lock_sock(sk);
2090 	sk->sk_lock.owned = 1;
2091 	spin_unlock(&sk->sk_lock.slock);
2092 	/*
2093 	 * The sk_lock has mutex_lock() semantics here:
2094 	 */
2095 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2096 	local_bh_enable();
2097 	return true;
2098 }
2099 EXPORT_SYMBOL(lock_sock_fast);
2100 
2101 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2102 {
2103 	struct timeval tv;
2104 	if (!sock_flag(sk, SOCK_TIMESTAMP))
2105 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2106 	tv = ktime_to_timeval(sk->sk_stamp);
2107 	if (tv.tv_sec == -1)
2108 		return -ENOENT;
2109 	if (tv.tv_sec == 0) {
2110 		sk->sk_stamp = ktime_get_real();
2111 		tv = ktime_to_timeval(sk->sk_stamp);
2112 	}
2113 	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2114 }
2115 EXPORT_SYMBOL(sock_get_timestamp);
2116 
2117 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2118 {
2119 	struct timespec ts;
2120 	if (!sock_flag(sk, SOCK_TIMESTAMP))
2121 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2122 	ts = ktime_to_timespec(sk->sk_stamp);
2123 	if (ts.tv_sec == -1)
2124 		return -ENOENT;
2125 	if (ts.tv_sec == 0) {
2126 		sk->sk_stamp = ktime_get_real();
2127 		ts = ktime_to_timespec(sk->sk_stamp);
2128 	}
2129 	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2130 }
2131 EXPORT_SYMBOL(sock_get_timestampns);
2132 
2133 void sock_enable_timestamp(struct sock *sk, int flag)
2134 {
2135 	if (!sock_flag(sk, flag)) {
2136 		sock_set_flag(sk, flag);
2137 		/*
2138 		 * we just set one of the two flags which require net
2139 		 * time stamping, but time stamping might have been on
2140 		 * already because of the other one
2141 		 */
2142 		if (!sock_flag(sk,
2143 				flag == SOCK_TIMESTAMP ?
2144 				SOCK_TIMESTAMPING_RX_SOFTWARE :
2145 				SOCK_TIMESTAMP))
2146 			net_enable_timestamp();
2147 	}
2148 }
2149 
2150 /*
2151  *	Get a socket option on an socket.
2152  *
2153  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2154  *	asynchronous errors should be reported by getsockopt. We assume
2155  *	this means if you specify SO_ERROR (otherwise whats the point of it).
2156  */
2157 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2158 			   char __user *optval, int __user *optlen)
2159 {
2160 	struct sock *sk = sock->sk;
2161 
2162 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2163 }
2164 EXPORT_SYMBOL(sock_common_getsockopt);
2165 
2166 #ifdef CONFIG_COMPAT
2167 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2168 				  char __user *optval, int __user *optlen)
2169 {
2170 	struct sock *sk = sock->sk;
2171 
2172 	if (sk->sk_prot->compat_getsockopt != NULL)
2173 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2174 						      optval, optlen);
2175 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2176 }
2177 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2178 #endif
2179 
2180 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2181 			struct msghdr *msg, size_t size, int flags)
2182 {
2183 	struct sock *sk = sock->sk;
2184 	int addr_len = 0;
2185 	int err;
2186 
2187 	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2188 				   flags & ~MSG_DONTWAIT, &addr_len);
2189 	if (err >= 0)
2190 		msg->msg_namelen = addr_len;
2191 	return err;
2192 }
2193 EXPORT_SYMBOL(sock_common_recvmsg);
2194 
2195 /*
2196  *	Set socket options on an inet socket.
2197  */
2198 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2199 			   char __user *optval, unsigned int optlen)
2200 {
2201 	struct sock *sk = sock->sk;
2202 
2203 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2204 }
2205 EXPORT_SYMBOL(sock_common_setsockopt);
2206 
2207 #ifdef CONFIG_COMPAT
2208 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2209 				  char __user *optval, unsigned int optlen)
2210 {
2211 	struct sock *sk = sock->sk;
2212 
2213 	if (sk->sk_prot->compat_setsockopt != NULL)
2214 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2215 						      optval, optlen);
2216 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2217 }
2218 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2219 #endif
2220 
2221 void sk_common_release(struct sock *sk)
2222 {
2223 	if (sk->sk_prot->destroy)
2224 		sk->sk_prot->destroy(sk);
2225 
2226 	/*
2227 	 * Observation: when sock_common_release is called, processes have
2228 	 * no access to socket. But net still has.
2229 	 * Step one, detach it from networking:
2230 	 *
2231 	 * A. Remove from hash tables.
2232 	 */
2233 
2234 	sk->sk_prot->unhash(sk);
2235 
2236 	/*
2237 	 * In this point socket cannot receive new packets, but it is possible
2238 	 * that some packets are in flight because some CPU runs receiver and
2239 	 * did hash table lookup before we unhashed socket. They will achieve
2240 	 * receive queue and will be purged by socket destructor.
2241 	 *
2242 	 * Also we still have packets pending on receive queue and probably,
2243 	 * our own packets waiting in device queues. sock_destroy will drain
2244 	 * receive queue, but transmitted packets will delay socket destruction
2245 	 * until the last reference will be released.
2246 	 */
2247 
2248 	sock_orphan(sk);
2249 
2250 	xfrm_sk_free_policy(sk);
2251 
2252 	sk_refcnt_debug_release(sk);
2253 	sock_put(sk);
2254 }
2255 EXPORT_SYMBOL(sk_common_release);
2256 
2257 static DEFINE_RWLOCK(proto_list_lock);
2258 static LIST_HEAD(proto_list);
2259 
2260 #ifdef CONFIG_PROC_FS
2261 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
2262 struct prot_inuse {
2263 	int val[PROTO_INUSE_NR];
2264 };
2265 
2266 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2267 
2268 #ifdef CONFIG_NET_NS
2269 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2270 {
2271 	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2272 }
2273 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2274 
2275 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2276 {
2277 	int cpu, idx = prot->inuse_idx;
2278 	int res = 0;
2279 
2280 	for_each_possible_cpu(cpu)
2281 		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2282 
2283 	return res >= 0 ? res : 0;
2284 }
2285 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2286 
2287 static int __net_init sock_inuse_init_net(struct net *net)
2288 {
2289 	net->core.inuse = alloc_percpu(struct prot_inuse);
2290 	return net->core.inuse ? 0 : -ENOMEM;
2291 }
2292 
2293 static void __net_exit sock_inuse_exit_net(struct net *net)
2294 {
2295 	free_percpu(net->core.inuse);
2296 }
2297 
2298 static struct pernet_operations net_inuse_ops = {
2299 	.init = sock_inuse_init_net,
2300 	.exit = sock_inuse_exit_net,
2301 };
2302 
2303 static __init int net_inuse_init(void)
2304 {
2305 	if (register_pernet_subsys(&net_inuse_ops))
2306 		panic("Cannot initialize net inuse counters");
2307 
2308 	return 0;
2309 }
2310 
2311 core_initcall(net_inuse_init);
2312 #else
2313 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2314 
2315 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2316 {
2317 	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2318 }
2319 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2320 
2321 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2322 {
2323 	int cpu, idx = prot->inuse_idx;
2324 	int res = 0;
2325 
2326 	for_each_possible_cpu(cpu)
2327 		res += per_cpu(prot_inuse, cpu).val[idx];
2328 
2329 	return res >= 0 ? res : 0;
2330 }
2331 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2332 #endif
2333 
2334 static void assign_proto_idx(struct proto *prot)
2335 {
2336 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2337 
2338 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2339 		printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2340 		return;
2341 	}
2342 
2343 	set_bit(prot->inuse_idx, proto_inuse_idx);
2344 }
2345 
2346 static void release_proto_idx(struct proto *prot)
2347 {
2348 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2349 		clear_bit(prot->inuse_idx, proto_inuse_idx);
2350 }
2351 #else
2352 static inline void assign_proto_idx(struct proto *prot)
2353 {
2354 }
2355 
2356 static inline void release_proto_idx(struct proto *prot)
2357 {
2358 }
2359 #endif
2360 
2361 int proto_register(struct proto *prot, int alloc_slab)
2362 {
2363 	if (alloc_slab) {
2364 		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2365 					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2366 					NULL);
2367 
2368 		if (prot->slab == NULL) {
2369 			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2370 			       prot->name);
2371 			goto out;
2372 		}
2373 
2374 		if (prot->rsk_prot != NULL) {
2375 			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2376 			if (prot->rsk_prot->slab_name == NULL)
2377 				goto out_free_sock_slab;
2378 
2379 			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2380 								 prot->rsk_prot->obj_size, 0,
2381 								 SLAB_HWCACHE_ALIGN, NULL);
2382 
2383 			if (prot->rsk_prot->slab == NULL) {
2384 				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2385 				       prot->name);
2386 				goto out_free_request_sock_slab_name;
2387 			}
2388 		}
2389 
2390 		if (prot->twsk_prot != NULL) {
2391 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2392 
2393 			if (prot->twsk_prot->twsk_slab_name == NULL)
2394 				goto out_free_request_sock_slab;
2395 
2396 			prot->twsk_prot->twsk_slab =
2397 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2398 						  prot->twsk_prot->twsk_obj_size,
2399 						  0,
2400 						  SLAB_HWCACHE_ALIGN |
2401 							prot->slab_flags,
2402 						  NULL);
2403 			if (prot->twsk_prot->twsk_slab == NULL)
2404 				goto out_free_timewait_sock_slab_name;
2405 		}
2406 	}
2407 
2408 	write_lock(&proto_list_lock);
2409 	list_add(&prot->node, &proto_list);
2410 	assign_proto_idx(prot);
2411 	write_unlock(&proto_list_lock);
2412 	return 0;
2413 
2414 out_free_timewait_sock_slab_name:
2415 	kfree(prot->twsk_prot->twsk_slab_name);
2416 out_free_request_sock_slab:
2417 	if (prot->rsk_prot && prot->rsk_prot->slab) {
2418 		kmem_cache_destroy(prot->rsk_prot->slab);
2419 		prot->rsk_prot->slab = NULL;
2420 	}
2421 out_free_request_sock_slab_name:
2422 	if (prot->rsk_prot)
2423 		kfree(prot->rsk_prot->slab_name);
2424 out_free_sock_slab:
2425 	kmem_cache_destroy(prot->slab);
2426 	prot->slab = NULL;
2427 out:
2428 	return -ENOBUFS;
2429 }
2430 EXPORT_SYMBOL(proto_register);
2431 
2432 void proto_unregister(struct proto *prot)
2433 {
2434 	write_lock(&proto_list_lock);
2435 	release_proto_idx(prot);
2436 	list_del(&prot->node);
2437 	write_unlock(&proto_list_lock);
2438 
2439 	if (prot->slab != NULL) {
2440 		kmem_cache_destroy(prot->slab);
2441 		prot->slab = NULL;
2442 	}
2443 
2444 	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2445 		kmem_cache_destroy(prot->rsk_prot->slab);
2446 		kfree(prot->rsk_prot->slab_name);
2447 		prot->rsk_prot->slab = NULL;
2448 	}
2449 
2450 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2451 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2452 		kfree(prot->twsk_prot->twsk_slab_name);
2453 		prot->twsk_prot->twsk_slab = NULL;
2454 	}
2455 }
2456 EXPORT_SYMBOL(proto_unregister);
2457 
2458 #ifdef CONFIG_PROC_FS
2459 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2460 	__acquires(proto_list_lock)
2461 {
2462 	read_lock(&proto_list_lock);
2463 	return seq_list_start_head(&proto_list, *pos);
2464 }
2465 
2466 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2467 {
2468 	return seq_list_next(v, &proto_list, pos);
2469 }
2470 
2471 static void proto_seq_stop(struct seq_file *seq, void *v)
2472 	__releases(proto_list_lock)
2473 {
2474 	read_unlock(&proto_list_lock);
2475 }
2476 
2477 static char proto_method_implemented(const void *method)
2478 {
2479 	return method == NULL ? 'n' : 'y';
2480 }
2481 
2482 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2483 {
2484 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2485 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2486 		   proto->name,
2487 		   proto->obj_size,
2488 		   sock_prot_inuse_get(seq_file_net(seq), proto),
2489 		   proto->memory_allocated != NULL ? atomic_long_read(proto->memory_allocated) : -1L,
2490 		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2491 		   proto->max_header,
2492 		   proto->slab == NULL ? "no" : "yes",
2493 		   module_name(proto->owner),
2494 		   proto_method_implemented(proto->close),
2495 		   proto_method_implemented(proto->connect),
2496 		   proto_method_implemented(proto->disconnect),
2497 		   proto_method_implemented(proto->accept),
2498 		   proto_method_implemented(proto->ioctl),
2499 		   proto_method_implemented(proto->init),
2500 		   proto_method_implemented(proto->destroy),
2501 		   proto_method_implemented(proto->shutdown),
2502 		   proto_method_implemented(proto->setsockopt),
2503 		   proto_method_implemented(proto->getsockopt),
2504 		   proto_method_implemented(proto->sendmsg),
2505 		   proto_method_implemented(proto->recvmsg),
2506 		   proto_method_implemented(proto->sendpage),
2507 		   proto_method_implemented(proto->bind),
2508 		   proto_method_implemented(proto->backlog_rcv),
2509 		   proto_method_implemented(proto->hash),
2510 		   proto_method_implemented(proto->unhash),
2511 		   proto_method_implemented(proto->get_port),
2512 		   proto_method_implemented(proto->enter_memory_pressure));
2513 }
2514 
2515 static int proto_seq_show(struct seq_file *seq, void *v)
2516 {
2517 	if (v == &proto_list)
2518 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2519 			   "protocol",
2520 			   "size",
2521 			   "sockets",
2522 			   "memory",
2523 			   "press",
2524 			   "maxhdr",
2525 			   "slab",
2526 			   "module",
2527 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2528 	else
2529 		proto_seq_printf(seq, list_entry(v, struct proto, node));
2530 	return 0;
2531 }
2532 
2533 static const struct seq_operations proto_seq_ops = {
2534 	.start  = proto_seq_start,
2535 	.next   = proto_seq_next,
2536 	.stop   = proto_seq_stop,
2537 	.show   = proto_seq_show,
2538 };
2539 
2540 static int proto_seq_open(struct inode *inode, struct file *file)
2541 {
2542 	return seq_open_net(inode, file, &proto_seq_ops,
2543 			    sizeof(struct seq_net_private));
2544 }
2545 
2546 static const struct file_operations proto_seq_fops = {
2547 	.owner		= THIS_MODULE,
2548 	.open		= proto_seq_open,
2549 	.read		= seq_read,
2550 	.llseek		= seq_lseek,
2551 	.release	= seq_release_net,
2552 };
2553 
2554 static __net_init int proto_init_net(struct net *net)
2555 {
2556 	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2557 		return -ENOMEM;
2558 
2559 	return 0;
2560 }
2561 
2562 static __net_exit void proto_exit_net(struct net *net)
2563 {
2564 	proc_net_remove(net, "protocols");
2565 }
2566 
2567 
2568 static __net_initdata struct pernet_operations proto_net_ops = {
2569 	.init = proto_init_net,
2570 	.exit = proto_exit_net,
2571 };
2572 
2573 static int __init proto_init(void)
2574 {
2575 	return register_pernet_subsys(&proto_net_ops);
2576 }
2577 
2578 subsys_initcall(proto_init);
2579 
2580 #endif /* PROC_FS */
2581