sock.c revision e812347ccf9e8ce073b0ba0c49d03b124707b2b4
1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  INET is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Generic socket support routines. Memory allocators, socket lock/release
7 *		handler for protocols to use and generic option handler.
8 *
9 *
10 * Authors:	Ross Biro
11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *		Florian La Roche, <flla@stud.uni-sb.de>
13 *		Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 *		Alan Cox	: 	Numerous verify_area() problems
17 *		Alan Cox	:	Connecting on a connecting socket
18 *					now returns an error for tcp.
19 *		Alan Cox	:	sock->protocol is set correctly.
20 *					and is not sometimes left as 0.
21 *		Alan Cox	:	connect handles icmp errors on a
22 *					connect properly. Unfortunately there
23 *					is a restart syscall nasty there. I
24 *					can't match BSD without hacking the C
25 *					library. Ideas urgently sought!
26 *		Alan Cox	:	Disallow bind() to addresses that are
27 *					not ours - especially broadcast ones!!
28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30 *					instead they leave that for the DESTROY timer.
31 *		Alan Cox	:	Clean up error flag in accept
32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33 *					was buggy. Put a remove_sock() in the handler
34 *					for memory when we hit 0. Also altered the timer
35 *					code. The ACK stuff can wait and needs major
36 *					TCP layer surgery.
37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38 *					and fixed timer/inet_bh race.
39 *		Alan Cox	:	Added zapped flag for TCP
40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47 *	Pauline Middelink	:	identd support
48 *		Alan Cox	:	Fixed connect() taking signals I think.
49 *		Alan Cox	:	SO_LINGER supported
50 *		Alan Cox	:	Error reporting fixes
51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52 *		Alan Cox	:	inet sockets don't set sk->type!
53 *		Alan Cox	:	Split socket option code
54 *		Alan Cox	:	Callbacks
55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56 *		Alex		:	Removed restriction on inet fioctl
57 *		Alan Cox	:	Splitting INET from NET core
58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60 *		Alan Cox	:	Split IP from generic code
61 *		Alan Cox	:	New kfree_skbmem()
62 *		Alan Cox	:	Make SO_DEBUG superuser only.
63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64 *					(compatibility fix)
65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66 *		Alan Cox	:	Allocator for a socket is settable.
67 *		Alan Cox	:	SO_ERROR includes soft errors.
68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69 *		Alan Cox	: 	Generic socket allocation to make hooks
70 *					easier (suggested by Craig Metz).
71 *		Michael Pall	:	SO_ERROR returns positive errno again
72 *              Steve Whitehouse:       Added default destructor to free
73 *                                      protocol private data.
74 *              Steve Whitehouse:       Added various other default routines
75 *                                      common to several socket families.
76 *              Chris Evans     :       Call suser() check last on F_SETOWN
77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79 *		Andi Kleen	:	Fix write_space callback
80 *		Chris Evans	:	Security fixes - signedness again
81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 *		This program is free software; you can redistribute it and/or
87 *		modify it under the terms of the GNU General Public License
88 *		as published by the Free Software Foundation; either version
89 *		2 of the License, or (at your option) any later version.
90 */
91
92#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93
94#include <linux/capability.h>
95#include <linux/errno.h>
96#include <linux/types.h>
97#include <linux/socket.h>
98#include <linux/in.h>
99#include <linux/kernel.h>
100#include <linux/module.h>
101#include <linux/proc_fs.h>
102#include <linux/seq_file.h>
103#include <linux/sched.h>
104#include <linux/timer.h>
105#include <linux/string.h>
106#include <linux/sockios.h>
107#include <linux/net.h>
108#include <linux/mm.h>
109#include <linux/slab.h>
110#include <linux/interrupt.h>
111#include <linux/poll.h>
112#include <linux/tcp.h>
113#include <linux/init.h>
114#include <linux/highmem.h>
115#include <linux/user_namespace.h>
116#include <linux/static_key.h>
117#include <linux/memcontrol.h>
118#include <linux/prefetch.h>
119
120#include <asm/uaccess.h>
121
122#include <linux/netdevice.h>
123#include <net/protocol.h>
124#include <linux/skbuff.h>
125#include <net/net_namespace.h>
126#include <net/request_sock.h>
127#include <net/sock.h>
128#include <linux/net_tstamp.h>
129#include <net/xfrm.h>
130#include <linux/ipsec.h>
131#include <net/cls_cgroup.h>
132#include <net/netprio_cgroup.h>
133
134#include <linux/filter.h>
135
136#include <trace/events/sock.h>
137
138#ifdef CONFIG_INET
139#include <net/tcp.h>
140#endif
141
142static DEFINE_MUTEX(proto_list_mutex);
143static LIST_HEAD(proto_list);
144
145#ifdef CONFIG_MEMCG_KMEM
146int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
147{
148	struct proto *proto;
149	int ret = 0;
150
151	mutex_lock(&proto_list_mutex);
152	list_for_each_entry(proto, &proto_list, node) {
153		if (proto->init_cgroup) {
154			ret = proto->init_cgroup(memcg, ss);
155			if (ret)
156				goto out;
157		}
158	}
159
160	mutex_unlock(&proto_list_mutex);
161	return ret;
162out:
163	list_for_each_entry_continue_reverse(proto, &proto_list, node)
164		if (proto->destroy_cgroup)
165			proto->destroy_cgroup(memcg);
166	mutex_unlock(&proto_list_mutex);
167	return ret;
168}
169
170void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
171{
172	struct proto *proto;
173
174	mutex_lock(&proto_list_mutex);
175	list_for_each_entry_reverse(proto, &proto_list, node)
176		if (proto->destroy_cgroup)
177			proto->destroy_cgroup(memcg);
178	mutex_unlock(&proto_list_mutex);
179}
180#endif
181
182/*
183 * Each address family might have different locking rules, so we have
184 * one slock key per address family:
185 */
186static struct lock_class_key af_family_keys[AF_MAX];
187static struct lock_class_key af_family_slock_keys[AF_MAX];
188
189struct static_key memcg_socket_limit_enabled;
190EXPORT_SYMBOL(memcg_socket_limit_enabled);
191
192/*
193 * Make lock validator output more readable. (we pre-construct these
194 * strings build-time, so that runtime initialization of socket
195 * locks is fast):
196 */
197static const char *const af_family_key_strings[AF_MAX+1] = {
198  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
199  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
200  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
201  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
202  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
203  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
204  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
205  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
206  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
207  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
208  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
209  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
210  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
211  "sk_lock-AF_NFC"   , "sk_lock-AF_MAX"
212};
213static const char *const af_family_slock_key_strings[AF_MAX+1] = {
214  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
215  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
216  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
217  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
218  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
219  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
220  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
221  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
222  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
223  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
224  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
225  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
226  "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
227  "slock-AF_NFC"   , "slock-AF_MAX"
228};
229static const char *const af_family_clock_key_strings[AF_MAX+1] = {
230  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
231  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
232  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
233  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
234  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
235  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
236  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
237  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
238  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
239  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
240  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
241  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
242  "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
243  "clock-AF_NFC"   , "clock-AF_MAX"
244};
245
246/*
247 * sk_callback_lock locking rules are per-address-family,
248 * so split the lock classes by using a per-AF key:
249 */
250static struct lock_class_key af_callback_keys[AF_MAX];
251
252/* Take into consideration the size of the struct sk_buff overhead in the
253 * determination of these values, since that is non-constant across
254 * platforms.  This makes socket queueing behavior and performance
255 * not depend upon such differences.
256 */
257#define _SK_MEM_PACKETS		256
258#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
259#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
260#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
261
262/* Run time adjustable parameters. */
263__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
264EXPORT_SYMBOL(sysctl_wmem_max);
265__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
266EXPORT_SYMBOL(sysctl_rmem_max);
267__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
268__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
269
270/* Maximal space eaten by iovec or ancillary data plus some space */
271int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
272EXPORT_SYMBOL(sysctl_optmem_max);
273
274struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
275EXPORT_SYMBOL_GPL(memalloc_socks);
276
277/**
278 * sk_set_memalloc - sets %SOCK_MEMALLOC
279 * @sk: socket to set it on
280 *
281 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
282 * It's the responsibility of the admin to adjust min_free_kbytes
283 * to meet the requirements
284 */
285void sk_set_memalloc(struct sock *sk)
286{
287	sock_set_flag(sk, SOCK_MEMALLOC);
288	sk->sk_allocation |= __GFP_MEMALLOC;
289	static_key_slow_inc(&memalloc_socks);
290}
291EXPORT_SYMBOL_GPL(sk_set_memalloc);
292
293void sk_clear_memalloc(struct sock *sk)
294{
295	sock_reset_flag(sk, SOCK_MEMALLOC);
296	sk->sk_allocation &= ~__GFP_MEMALLOC;
297	static_key_slow_dec(&memalloc_socks);
298
299	/*
300	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
301	 * progress of swapping. However, if SOCK_MEMALLOC is cleared while
302	 * it has rmem allocations there is a risk that the user of the
303	 * socket cannot make forward progress due to exceeding the rmem
304	 * limits. By rights, sk_clear_memalloc() should only be called
305	 * on sockets being torn down but warn and reset the accounting if
306	 * that assumption breaks.
307	 */
308	if (WARN_ON(sk->sk_forward_alloc))
309		sk_mem_reclaim(sk);
310}
311EXPORT_SYMBOL_GPL(sk_clear_memalloc);
312
313int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
314{
315	int ret;
316	unsigned long pflags = current->flags;
317
318	/* these should have been dropped before queueing */
319	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
320
321	current->flags |= PF_MEMALLOC;
322	ret = sk->sk_backlog_rcv(sk, skb);
323	tsk_restore_flags(current, pflags, PF_MEMALLOC);
324
325	return ret;
326}
327EXPORT_SYMBOL(__sk_backlog_rcv);
328
329#if defined(CONFIG_CGROUPS)
330#if !defined(CONFIG_NET_CLS_CGROUP)
331int net_cls_subsys_id = -1;
332EXPORT_SYMBOL_GPL(net_cls_subsys_id);
333#endif
334#if !defined(CONFIG_NETPRIO_CGROUP)
335int net_prio_subsys_id = -1;
336EXPORT_SYMBOL_GPL(net_prio_subsys_id);
337#endif
338#endif
339
340static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
341{
342	struct timeval tv;
343
344	if (optlen < sizeof(tv))
345		return -EINVAL;
346	if (copy_from_user(&tv, optval, sizeof(tv)))
347		return -EFAULT;
348	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
349		return -EDOM;
350
351	if (tv.tv_sec < 0) {
352		static int warned __read_mostly;
353
354		*timeo_p = 0;
355		if (warned < 10 && net_ratelimit()) {
356			warned++;
357			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
358				__func__, current->comm, task_pid_nr(current));
359		}
360		return 0;
361	}
362	*timeo_p = MAX_SCHEDULE_TIMEOUT;
363	if (tv.tv_sec == 0 && tv.tv_usec == 0)
364		return 0;
365	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
366		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
367	return 0;
368}
369
370static void sock_warn_obsolete_bsdism(const char *name)
371{
372	static int warned;
373	static char warncomm[TASK_COMM_LEN];
374	if (strcmp(warncomm, current->comm) && warned < 5) {
375		strcpy(warncomm,  current->comm);
376		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
377			warncomm, name);
378		warned++;
379	}
380}
381
382#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
383
384static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
385{
386	if (sk->sk_flags & flags) {
387		sk->sk_flags &= ~flags;
388		if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
389			net_disable_timestamp();
390	}
391}
392
393
394int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
395{
396	int err;
397	int skb_len;
398	unsigned long flags;
399	struct sk_buff_head *list = &sk->sk_receive_queue;
400
401	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
402		atomic_inc(&sk->sk_drops);
403		trace_sock_rcvqueue_full(sk, skb);
404		return -ENOMEM;
405	}
406
407	err = sk_filter(sk, skb);
408	if (err)
409		return err;
410
411	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
412		atomic_inc(&sk->sk_drops);
413		return -ENOBUFS;
414	}
415
416	skb->dev = NULL;
417	skb_set_owner_r(skb, sk);
418
419	/* Cache the SKB length before we tack it onto the receive
420	 * queue.  Once it is added it no longer belongs to us and
421	 * may be freed by other threads of control pulling packets
422	 * from the queue.
423	 */
424	skb_len = skb->len;
425
426	/* we escape from rcu protected region, make sure we dont leak
427	 * a norefcounted dst
428	 */
429	skb_dst_force(skb);
430
431	spin_lock_irqsave(&list->lock, flags);
432	skb->dropcount = atomic_read(&sk->sk_drops);
433	__skb_queue_tail(list, skb);
434	spin_unlock_irqrestore(&list->lock, flags);
435
436	if (!sock_flag(sk, SOCK_DEAD))
437		sk->sk_data_ready(sk, skb_len);
438	return 0;
439}
440EXPORT_SYMBOL(sock_queue_rcv_skb);
441
442int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
443{
444	int rc = NET_RX_SUCCESS;
445
446	if (sk_filter(sk, skb))
447		goto discard_and_relse;
448
449	skb->dev = NULL;
450
451	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
452		atomic_inc(&sk->sk_drops);
453		goto discard_and_relse;
454	}
455	if (nested)
456		bh_lock_sock_nested(sk);
457	else
458		bh_lock_sock(sk);
459	if (!sock_owned_by_user(sk)) {
460		/*
461		 * trylock + unlock semantics:
462		 */
463		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
464
465		rc = sk_backlog_rcv(sk, skb);
466
467		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
468	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
469		bh_unlock_sock(sk);
470		atomic_inc(&sk->sk_drops);
471		goto discard_and_relse;
472	}
473
474	bh_unlock_sock(sk);
475out:
476	sock_put(sk);
477	return rc;
478discard_and_relse:
479	kfree_skb(skb);
480	goto out;
481}
482EXPORT_SYMBOL(sk_receive_skb);
483
484void sk_reset_txq(struct sock *sk)
485{
486	sk_tx_queue_clear(sk);
487}
488EXPORT_SYMBOL(sk_reset_txq);
489
490struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
491{
492	struct dst_entry *dst = __sk_dst_get(sk);
493
494	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
495		sk_tx_queue_clear(sk);
496		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
497		dst_release(dst);
498		return NULL;
499	}
500
501	return dst;
502}
503EXPORT_SYMBOL(__sk_dst_check);
504
505struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
506{
507	struct dst_entry *dst = sk_dst_get(sk);
508
509	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
510		sk_dst_reset(sk);
511		dst_release(dst);
512		return NULL;
513	}
514
515	return dst;
516}
517EXPORT_SYMBOL(sk_dst_check);
518
519static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
520{
521	int ret = -ENOPROTOOPT;
522#ifdef CONFIG_NETDEVICES
523	struct net *net = sock_net(sk);
524	char devname[IFNAMSIZ];
525	int index;
526
527	/* Sorry... */
528	ret = -EPERM;
529	if (!capable(CAP_NET_RAW))
530		goto out;
531
532	ret = -EINVAL;
533	if (optlen < 0)
534		goto out;
535
536	/* Bind this socket to a particular device like "eth0",
537	 * as specified in the passed interface name. If the
538	 * name is "" or the option length is zero the socket
539	 * is not bound.
540	 */
541	if (optlen > IFNAMSIZ - 1)
542		optlen = IFNAMSIZ - 1;
543	memset(devname, 0, sizeof(devname));
544
545	ret = -EFAULT;
546	if (copy_from_user(devname, optval, optlen))
547		goto out;
548
549	index = 0;
550	if (devname[0] != '\0') {
551		struct net_device *dev;
552
553		rcu_read_lock();
554		dev = dev_get_by_name_rcu(net, devname);
555		if (dev)
556			index = dev->ifindex;
557		rcu_read_unlock();
558		ret = -ENODEV;
559		if (!dev)
560			goto out;
561	}
562
563	lock_sock(sk);
564	sk->sk_bound_dev_if = index;
565	sk_dst_reset(sk);
566	release_sock(sk);
567
568	ret = 0;
569
570out:
571#endif
572
573	return ret;
574}
575
576static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
577{
578	if (valbool)
579		sock_set_flag(sk, bit);
580	else
581		sock_reset_flag(sk, bit);
582}
583
584/*
585 *	This is meant for all protocols to use and covers goings on
586 *	at the socket level. Everything here is generic.
587 */
588
589int sock_setsockopt(struct socket *sock, int level, int optname,
590		    char __user *optval, unsigned int optlen)
591{
592	struct sock *sk = sock->sk;
593	int val;
594	int valbool;
595	struct linger ling;
596	int ret = 0;
597
598	/*
599	 *	Options without arguments
600	 */
601
602	if (optname == SO_BINDTODEVICE)
603		return sock_bindtodevice(sk, optval, optlen);
604
605	if (optlen < sizeof(int))
606		return -EINVAL;
607
608	if (get_user(val, (int __user *)optval))
609		return -EFAULT;
610
611	valbool = val ? 1 : 0;
612
613	lock_sock(sk);
614
615	switch (optname) {
616	case SO_DEBUG:
617		if (val && !capable(CAP_NET_ADMIN))
618			ret = -EACCES;
619		else
620			sock_valbool_flag(sk, SOCK_DBG, valbool);
621		break;
622	case SO_REUSEADDR:
623		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
624		break;
625	case SO_TYPE:
626	case SO_PROTOCOL:
627	case SO_DOMAIN:
628	case SO_ERROR:
629		ret = -ENOPROTOOPT;
630		break;
631	case SO_DONTROUTE:
632		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
633		break;
634	case SO_BROADCAST:
635		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
636		break;
637	case SO_SNDBUF:
638		/* Don't error on this BSD doesn't and if you think
639		 * about it this is right. Otherwise apps have to
640		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
641		 * are treated in BSD as hints
642		 */
643		val = min_t(u32, val, sysctl_wmem_max);
644set_sndbuf:
645		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
646		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
647		/* Wake up sending tasks if we upped the value. */
648		sk->sk_write_space(sk);
649		break;
650
651	case SO_SNDBUFFORCE:
652		if (!capable(CAP_NET_ADMIN)) {
653			ret = -EPERM;
654			break;
655		}
656		goto set_sndbuf;
657
658	case SO_RCVBUF:
659		/* Don't error on this BSD doesn't and if you think
660		 * about it this is right. Otherwise apps have to
661		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
662		 * are treated in BSD as hints
663		 */
664		val = min_t(u32, val, sysctl_rmem_max);
665set_rcvbuf:
666		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
667		/*
668		 * We double it on the way in to account for
669		 * "struct sk_buff" etc. overhead.   Applications
670		 * assume that the SO_RCVBUF setting they make will
671		 * allow that much actual data to be received on that
672		 * socket.
673		 *
674		 * Applications are unaware that "struct sk_buff" and
675		 * other overheads allocate from the receive buffer
676		 * during socket buffer allocation.
677		 *
678		 * And after considering the possible alternatives,
679		 * returning the value we actually used in getsockopt
680		 * is the most desirable behavior.
681		 */
682		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
683		break;
684
685	case SO_RCVBUFFORCE:
686		if (!capable(CAP_NET_ADMIN)) {
687			ret = -EPERM;
688			break;
689		}
690		goto set_rcvbuf;
691
692	case SO_KEEPALIVE:
693#ifdef CONFIG_INET
694		if (sk->sk_protocol == IPPROTO_TCP)
695			tcp_set_keepalive(sk, valbool);
696#endif
697		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
698		break;
699
700	case SO_OOBINLINE:
701		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
702		break;
703
704	case SO_NO_CHECK:
705		sk->sk_no_check = valbool;
706		break;
707
708	case SO_PRIORITY:
709		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
710			sk->sk_priority = val;
711		else
712			ret = -EPERM;
713		break;
714
715	case SO_LINGER:
716		if (optlen < sizeof(ling)) {
717			ret = -EINVAL;	/* 1003.1g */
718			break;
719		}
720		if (copy_from_user(&ling, optval, sizeof(ling))) {
721			ret = -EFAULT;
722			break;
723		}
724		if (!ling.l_onoff)
725			sock_reset_flag(sk, SOCK_LINGER);
726		else {
727#if (BITS_PER_LONG == 32)
728			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
729				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
730			else
731#endif
732				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
733			sock_set_flag(sk, SOCK_LINGER);
734		}
735		break;
736
737	case SO_BSDCOMPAT:
738		sock_warn_obsolete_bsdism("setsockopt");
739		break;
740
741	case SO_PASSCRED:
742		if (valbool)
743			set_bit(SOCK_PASSCRED, &sock->flags);
744		else
745			clear_bit(SOCK_PASSCRED, &sock->flags);
746		break;
747
748	case SO_TIMESTAMP:
749	case SO_TIMESTAMPNS:
750		if (valbool)  {
751			if (optname == SO_TIMESTAMP)
752				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
753			else
754				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
755			sock_set_flag(sk, SOCK_RCVTSTAMP);
756			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
757		} else {
758			sock_reset_flag(sk, SOCK_RCVTSTAMP);
759			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
760		}
761		break;
762
763	case SO_TIMESTAMPING:
764		if (val & ~SOF_TIMESTAMPING_MASK) {
765			ret = -EINVAL;
766			break;
767		}
768		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
769				  val & SOF_TIMESTAMPING_TX_HARDWARE);
770		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
771				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
772		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
773				  val & SOF_TIMESTAMPING_RX_HARDWARE);
774		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
775			sock_enable_timestamp(sk,
776					      SOCK_TIMESTAMPING_RX_SOFTWARE);
777		else
778			sock_disable_timestamp(sk,
779					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
780		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
781				  val & SOF_TIMESTAMPING_SOFTWARE);
782		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
783				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
784		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
785				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
786		break;
787
788	case SO_RCVLOWAT:
789		if (val < 0)
790			val = INT_MAX;
791		sk->sk_rcvlowat = val ? : 1;
792		break;
793
794	case SO_RCVTIMEO:
795		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
796		break;
797
798	case SO_SNDTIMEO:
799		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
800		break;
801
802	case SO_ATTACH_FILTER:
803		ret = -EINVAL;
804		if (optlen == sizeof(struct sock_fprog)) {
805			struct sock_fprog fprog;
806
807			ret = -EFAULT;
808			if (copy_from_user(&fprog, optval, sizeof(fprog)))
809				break;
810
811			ret = sk_attach_filter(&fprog, sk);
812		}
813		break;
814
815	case SO_DETACH_FILTER:
816		ret = sk_detach_filter(sk);
817		break;
818
819	case SO_PASSSEC:
820		if (valbool)
821			set_bit(SOCK_PASSSEC, &sock->flags);
822		else
823			clear_bit(SOCK_PASSSEC, &sock->flags);
824		break;
825	case SO_MARK:
826		if (!capable(CAP_NET_ADMIN))
827			ret = -EPERM;
828		else
829			sk->sk_mark = val;
830		break;
831
832		/* We implement the SO_SNDLOWAT etc to
833		   not be settable (1003.1g 5.3) */
834	case SO_RXQ_OVFL:
835		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
836		break;
837
838	case SO_WIFI_STATUS:
839		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
840		break;
841
842	case SO_PEEK_OFF:
843		if (sock->ops->set_peek_off)
844			sock->ops->set_peek_off(sk, val);
845		else
846			ret = -EOPNOTSUPP;
847		break;
848
849	case SO_NOFCS:
850		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
851		break;
852
853	default:
854		ret = -ENOPROTOOPT;
855		break;
856	}
857	release_sock(sk);
858	return ret;
859}
860EXPORT_SYMBOL(sock_setsockopt);
861
862
863void cred_to_ucred(struct pid *pid, const struct cred *cred,
864		   struct ucred *ucred)
865{
866	ucred->pid = pid_vnr(pid);
867	ucred->uid = ucred->gid = -1;
868	if (cred) {
869		struct user_namespace *current_ns = current_user_ns();
870
871		ucred->uid = from_kuid(current_ns, cred->euid);
872		ucred->gid = from_kgid(current_ns, cred->egid);
873	}
874}
875EXPORT_SYMBOL_GPL(cred_to_ucred);
876
877int sock_getsockopt(struct socket *sock, int level, int optname,
878		    char __user *optval, int __user *optlen)
879{
880	struct sock *sk = sock->sk;
881
882	union {
883		int val;
884		struct linger ling;
885		struct timeval tm;
886	} v;
887
888	int lv = sizeof(int);
889	int len;
890
891	if (get_user(len, optlen))
892		return -EFAULT;
893	if (len < 0)
894		return -EINVAL;
895
896	memset(&v, 0, sizeof(v));
897
898	switch (optname) {
899	case SO_DEBUG:
900		v.val = sock_flag(sk, SOCK_DBG);
901		break;
902
903	case SO_DONTROUTE:
904		v.val = sock_flag(sk, SOCK_LOCALROUTE);
905		break;
906
907	case SO_BROADCAST:
908		v.val = sock_flag(sk, SOCK_BROADCAST);
909		break;
910
911	case SO_SNDBUF:
912		v.val = sk->sk_sndbuf;
913		break;
914
915	case SO_RCVBUF:
916		v.val = sk->sk_rcvbuf;
917		break;
918
919	case SO_REUSEADDR:
920		v.val = sk->sk_reuse;
921		break;
922
923	case SO_KEEPALIVE:
924		v.val = sock_flag(sk, SOCK_KEEPOPEN);
925		break;
926
927	case SO_TYPE:
928		v.val = sk->sk_type;
929		break;
930
931	case SO_PROTOCOL:
932		v.val = sk->sk_protocol;
933		break;
934
935	case SO_DOMAIN:
936		v.val = sk->sk_family;
937		break;
938
939	case SO_ERROR:
940		v.val = -sock_error(sk);
941		if (v.val == 0)
942			v.val = xchg(&sk->sk_err_soft, 0);
943		break;
944
945	case SO_OOBINLINE:
946		v.val = sock_flag(sk, SOCK_URGINLINE);
947		break;
948
949	case SO_NO_CHECK:
950		v.val = sk->sk_no_check;
951		break;
952
953	case SO_PRIORITY:
954		v.val = sk->sk_priority;
955		break;
956
957	case SO_LINGER:
958		lv		= sizeof(v.ling);
959		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
960		v.ling.l_linger	= sk->sk_lingertime / HZ;
961		break;
962
963	case SO_BSDCOMPAT:
964		sock_warn_obsolete_bsdism("getsockopt");
965		break;
966
967	case SO_TIMESTAMP:
968		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
969				!sock_flag(sk, SOCK_RCVTSTAMPNS);
970		break;
971
972	case SO_TIMESTAMPNS:
973		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
974		break;
975
976	case SO_TIMESTAMPING:
977		v.val = 0;
978		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
979			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
980		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
981			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
982		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
983			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
984		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
985			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
986		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
987			v.val |= SOF_TIMESTAMPING_SOFTWARE;
988		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
989			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
990		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
991			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
992		break;
993
994	case SO_RCVTIMEO:
995		lv = sizeof(struct timeval);
996		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
997			v.tm.tv_sec = 0;
998			v.tm.tv_usec = 0;
999		} else {
1000			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1001			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1002		}
1003		break;
1004
1005	case SO_SNDTIMEO:
1006		lv = sizeof(struct timeval);
1007		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1008			v.tm.tv_sec = 0;
1009			v.tm.tv_usec = 0;
1010		} else {
1011			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1012			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1013		}
1014		break;
1015
1016	case SO_RCVLOWAT:
1017		v.val = sk->sk_rcvlowat;
1018		break;
1019
1020	case SO_SNDLOWAT:
1021		v.val = 1;
1022		break;
1023
1024	case SO_PASSCRED:
1025		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1026		break;
1027
1028	case SO_PEERCRED:
1029	{
1030		struct ucred peercred;
1031		if (len > sizeof(peercred))
1032			len = sizeof(peercred);
1033		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1034		if (copy_to_user(optval, &peercred, len))
1035			return -EFAULT;
1036		goto lenout;
1037	}
1038
1039	case SO_PEERNAME:
1040	{
1041		char address[128];
1042
1043		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1044			return -ENOTCONN;
1045		if (lv < len)
1046			return -EINVAL;
1047		if (copy_to_user(optval, address, len))
1048			return -EFAULT;
1049		goto lenout;
1050	}
1051
1052	/* Dubious BSD thing... Probably nobody even uses it, but
1053	 * the UNIX standard wants it for whatever reason... -DaveM
1054	 */
1055	case SO_ACCEPTCONN:
1056		v.val = sk->sk_state == TCP_LISTEN;
1057		break;
1058
1059	case SO_PASSSEC:
1060		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1061		break;
1062
1063	case SO_PEERSEC:
1064		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1065
1066	case SO_MARK:
1067		v.val = sk->sk_mark;
1068		break;
1069
1070	case SO_RXQ_OVFL:
1071		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1072		break;
1073
1074	case SO_WIFI_STATUS:
1075		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1076		break;
1077
1078	case SO_PEEK_OFF:
1079		if (!sock->ops->set_peek_off)
1080			return -EOPNOTSUPP;
1081
1082		v.val = sk->sk_peek_off;
1083		break;
1084	case SO_NOFCS:
1085		v.val = sock_flag(sk, SOCK_NOFCS);
1086		break;
1087	default:
1088		return -ENOPROTOOPT;
1089	}
1090
1091	if (len > lv)
1092		len = lv;
1093	if (copy_to_user(optval, &v, len))
1094		return -EFAULT;
1095lenout:
1096	if (put_user(len, optlen))
1097		return -EFAULT;
1098	return 0;
1099}
1100
1101/*
1102 * Initialize an sk_lock.
1103 *
1104 * (We also register the sk_lock with the lock validator.)
1105 */
1106static inline void sock_lock_init(struct sock *sk)
1107{
1108	sock_lock_init_class_and_name(sk,
1109			af_family_slock_key_strings[sk->sk_family],
1110			af_family_slock_keys + sk->sk_family,
1111			af_family_key_strings[sk->sk_family],
1112			af_family_keys + sk->sk_family);
1113}
1114
1115/*
1116 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1117 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1118 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1119 */
1120static void sock_copy(struct sock *nsk, const struct sock *osk)
1121{
1122#ifdef CONFIG_SECURITY_NETWORK
1123	void *sptr = nsk->sk_security;
1124#endif
1125	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1126
1127	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1128	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1129
1130#ifdef CONFIG_SECURITY_NETWORK
1131	nsk->sk_security = sptr;
1132	security_sk_clone(osk, nsk);
1133#endif
1134}
1135
1136/*
1137 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1138 * un-modified. Special care is taken when initializing object to zero.
1139 */
1140static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1141{
1142	if (offsetof(struct sock, sk_node.next) != 0)
1143		memset(sk, 0, offsetof(struct sock, sk_node.next));
1144	memset(&sk->sk_node.pprev, 0,
1145	       size - offsetof(struct sock, sk_node.pprev));
1146}
1147
1148void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1149{
1150	unsigned long nulls1, nulls2;
1151
1152	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1153	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1154	if (nulls1 > nulls2)
1155		swap(nulls1, nulls2);
1156
1157	if (nulls1 != 0)
1158		memset((char *)sk, 0, nulls1);
1159	memset((char *)sk + nulls1 + sizeof(void *), 0,
1160	       nulls2 - nulls1 - sizeof(void *));
1161	memset((char *)sk + nulls2 + sizeof(void *), 0,
1162	       size - nulls2 - sizeof(void *));
1163}
1164EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1165
1166static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1167		int family)
1168{
1169	struct sock *sk;
1170	struct kmem_cache *slab;
1171
1172	slab = prot->slab;
1173	if (slab != NULL) {
1174		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1175		if (!sk)
1176			return sk;
1177		if (priority & __GFP_ZERO) {
1178			if (prot->clear_sk)
1179				prot->clear_sk(sk, prot->obj_size);
1180			else
1181				sk_prot_clear_nulls(sk, prot->obj_size);
1182		}
1183	} else
1184		sk = kmalloc(prot->obj_size, priority);
1185
1186	if (sk != NULL) {
1187		kmemcheck_annotate_bitfield(sk, flags);
1188
1189		if (security_sk_alloc(sk, family, priority))
1190			goto out_free;
1191
1192		if (!try_module_get(prot->owner))
1193			goto out_free_sec;
1194		sk_tx_queue_clear(sk);
1195	}
1196
1197	return sk;
1198
1199out_free_sec:
1200	security_sk_free(sk);
1201out_free:
1202	if (slab != NULL)
1203		kmem_cache_free(slab, sk);
1204	else
1205		kfree(sk);
1206	return NULL;
1207}
1208
1209static void sk_prot_free(struct proto *prot, struct sock *sk)
1210{
1211	struct kmem_cache *slab;
1212	struct module *owner;
1213
1214	owner = prot->owner;
1215	slab = prot->slab;
1216
1217	security_sk_free(sk);
1218	if (slab != NULL)
1219		kmem_cache_free(slab, sk);
1220	else
1221		kfree(sk);
1222	module_put(owner);
1223}
1224
1225#ifdef CONFIG_CGROUPS
1226void sock_update_classid(struct sock *sk)
1227{
1228	u32 classid;
1229
1230	rcu_read_lock();  /* doing current task, which cannot vanish. */
1231	classid = task_cls_classid(current);
1232	rcu_read_unlock();
1233	if (classid && classid != sk->sk_classid)
1234		sk->sk_classid = classid;
1235}
1236EXPORT_SYMBOL(sock_update_classid);
1237
1238void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
1239{
1240	if (in_interrupt())
1241		return;
1242
1243	sk->sk_cgrp_prioidx = task_netprioidx(task);
1244}
1245EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1246#endif
1247
1248/**
1249 *	sk_alloc - All socket objects are allocated here
1250 *	@net: the applicable net namespace
1251 *	@family: protocol family
1252 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1253 *	@prot: struct proto associated with this new sock instance
1254 */
1255struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1256		      struct proto *prot)
1257{
1258	struct sock *sk;
1259
1260	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1261	if (sk) {
1262		sk->sk_family = family;
1263		/*
1264		 * See comment in struct sock definition to understand
1265		 * why we need sk_prot_creator -acme
1266		 */
1267		sk->sk_prot = sk->sk_prot_creator = prot;
1268		sock_lock_init(sk);
1269		sock_net_set(sk, get_net(net));
1270		atomic_set(&sk->sk_wmem_alloc, 1);
1271
1272		sock_update_classid(sk);
1273		sock_update_netprioidx(sk, current);
1274	}
1275
1276	return sk;
1277}
1278EXPORT_SYMBOL(sk_alloc);
1279
1280static void __sk_free(struct sock *sk)
1281{
1282	struct sk_filter *filter;
1283
1284	if (sk->sk_destruct)
1285		sk->sk_destruct(sk);
1286
1287	filter = rcu_dereference_check(sk->sk_filter,
1288				       atomic_read(&sk->sk_wmem_alloc) == 0);
1289	if (filter) {
1290		sk_filter_uncharge(sk, filter);
1291		RCU_INIT_POINTER(sk->sk_filter, NULL);
1292	}
1293
1294	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1295
1296	if (atomic_read(&sk->sk_omem_alloc))
1297		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1298			 __func__, atomic_read(&sk->sk_omem_alloc));
1299
1300	if (sk->sk_peer_cred)
1301		put_cred(sk->sk_peer_cred);
1302	put_pid(sk->sk_peer_pid);
1303	put_net(sock_net(sk));
1304	sk_prot_free(sk->sk_prot_creator, sk);
1305}
1306
1307void sk_free(struct sock *sk)
1308{
1309	/*
1310	 * We subtract one from sk_wmem_alloc and can know if
1311	 * some packets are still in some tx queue.
1312	 * If not null, sock_wfree() will call __sk_free(sk) later
1313	 */
1314	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1315		__sk_free(sk);
1316}
1317EXPORT_SYMBOL(sk_free);
1318
1319/*
1320 * Last sock_put should drop reference to sk->sk_net. It has already
1321 * been dropped in sk_change_net. Taking reference to stopping namespace
1322 * is not an option.
1323 * Take reference to a socket to remove it from hash _alive_ and after that
1324 * destroy it in the context of init_net.
1325 */
1326void sk_release_kernel(struct sock *sk)
1327{
1328	if (sk == NULL || sk->sk_socket == NULL)
1329		return;
1330
1331	sock_hold(sk);
1332	sock_release(sk->sk_socket);
1333	release_net(sock_net(sk));
1334	sock_net_set(sk, get_net(&init_net));
1335	sock_put(sk);
1336}
1337EXPORT_SYMBOL(sk_release_kernel);
1338
1339static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1340{
1341	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1342		sock_update_memcg(newsk);
1343}
1344
1345/**
1346 *	sk_clone_lock - clone a socket, and lock its clone
1347 *	@sk: the socket to clone
1348 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1349 *
1350 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1351 */
1352struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1353{
1354	struct sock *newsk;
1355
1356	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1357	if (newsk != NULL) {
1358		struct sk_filter *filter;
1359
1360		sock_copy(newsk, sk);
1361
1362		/* SANITY */
1363		get_net(sock_net(newsk));
1364		sk_node_init(&newsk->sk_node);
1365		sock_lock_init(newsk);
1366		bh_lock_sock(newsk);
1367		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1368		newsk->sk_backlog.len = 0;
1369
1370		atomic_set(&newsk->sk_rmem_alloc, 0);
1371		/*
1372		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1373		 */
1374		atomic_set(&newsk->sk_wmem_alloc, 1);
1375		atomic_set(&newsk->sk_omem_alloc, 0);
1376		skb_queue_head_init(&newsk->sk_receive_queue);
1377		skb_queue_head_init(&newsk->sk_write_queue);
1378#ifdef CONFIG_NET_DMA
1379		skb_queue_head_init(&newsk->sk_async_wait_queue);
1380#endif
1381
1382		spin_lock_init(&newsk->sk_dst_lock);
1383		rwlock_init(&newsk->sk_callback_lock);
1384		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1385				af_callback_keys + newsk->sk_family,
1386				af_family_clock_key_strings[newsk->sk_family]);
1387
1388		newsk->sk_dst_cache	= NULL;
1389		newsk->sk_wmem_queued	= 0;
1390		newsk->sk_forward_alloc = 0;
1391		newsk->sk_send_head	= NULL;
1392		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1393
1394		sock_reset_flag(newsk, SOCK_DONE);
1395		skb_queue_head_init(&newsk->sk_error_queue);
1396
1397		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1398		if (filter != NULL)
1399			sk_filter_charge(newsk, filter);
1400
1401		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1402			/* It is still raw copy of parent, so invalidate
1403			 * destructor and make plain sk_free() */
1404			newsk->sk_destruct = NULL;
1405			bh_unlock_sock(newsk);
1406			sk_free(newsk);
1407			newsk = NULL;
1408			goto out;
1409		}
1410
1411		newsk->sk_err	   = 0;
1412		newsk->sk_priority = 0;
1413		/*
1414		 * Before updating sk_refcnt, we must commit prior changes to memory
1415		 * (Documentation/RCU/rculist_nulls.txt for details)
1416		 */
1417		smp_wmb();
1418		atomic_set(&newsk->sk_refcnt, 2);
1419
1420		/*
1421		 * Increment the counter in the same struct proto as the master
1422		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1423		 * is the same as sk->sk_prot->socks, as this field was copied
1424		 * with memcpy).
1425		 *
1426		 * This _changes_ the previous behaviour, where
1427		 * tcp_create_openreq_child always was incrementing the
1428		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1429		 * to be taken into account in all callers. -acme
1430		 */
1431		sk_refcnt_debug_inc(newsk);
1432		sk_set_socket(newsk, NULL);
1433		newsk->sk_wq = NULL;
1434
1435		sk_update_clone(sk, newsk);
1436
1437		if (newsk->sk_prot->sockets_allocated)
1438			sk_sockets_allocated_inc(newsk);
1439
1440		if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1441			net_enable_timestamp();
1442	}
1443out:
1444	return newsk;
1445}
1446EXPORT_SYMBOL_GPL(sk_clone_lock);
1447
1448void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1449{
1450	__sk_dst_set(sk, dst);
1451	sk->sk_route_caps = dst->dev->features;
1452	if (sk->sk_route_caps & NETIF_F_GSO)
1453		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1454	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1455	if (sk_can_gso(sk)) {
1456		if (dst->header_len) {
1457			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1458		} else {
1459			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1460			sk->sk_gso_max_size = dst->dev->gso_max_size;
1461			sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1462		}
1463	}
1464}
1465EXPORT_SYMBOL_GPL(sk_setup_caps);
1466
1467void __init sk_init(void)
1468{
1469	if (totalram_pages <= 4096) {
1470		sysctl_wmem_max = 32767;
1471		sysctl_rmem_max = 32767;
1472		sysctl_wmem_default = 32767;
1473		sysctl_rmem_default = 32767;
1474	} else if (totalram_pages >= 131072) {
1475		sysctl_wmem_max = 131071;
1476		sysctl_rmem_max = 131071;
1477	}
1478}
1479
1480/*
1481 *	Simple resource managers for sockets.
1482 */
1483
1484
1485/*
1486 * Write buffer destructor automatically called from kfree_skb.
1487 */
1488void sock_wfree(struct sk_buff *skb)
1489{
1490	struct sock *sk = skb->sk;
1491	unsigned int len = skb->truesize;
1492
1493	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1494		/*
1495		 * Keep a reference on sk_wmem_alloc, this will be released
1496		 * after sk_write_space() call
1497		 */
1498		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1499		sk->sk_write_space(sk);
1500		len = 1;
1501	}
1502	/*
1503	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1504	 * could not do because of in-flight packets
1505	 */
1506	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1507		__sk_free(sk);
1508}
1509EXPORT_SYMBOL(sock_wfree);
1510
1511/*
1512 * Read buffer destructor automatically called from kfree_skb.
1513 */
1514void sock_rfree(struct sk_buff *skb)
1515{
1516	struct sock *sk = skb->sk;
1517	unsigned int len = skb->truesize;
1518
1519	atomic_sub(len, &sk->sk_rmem_alloc);
1520	sk_mem_uncharge(sk, len);
1521}
1522EXPORT_SYMBOL(sock_rfree);
1523
1524void sock_edemux(struct sk_buff *skb)
1525{
1526	struct sock *sk = skb->sk;
1527
1528	if (sk->sk_state == TCP_TIME_WAIT)
1529		inet_twsk_put(inet_twsk(sk));
1530	else
1531		sock_put(sk);
1532}
1533EXPORT_SYMBOL(sock_edemux);
1534
1535int sock_i_uid(struct sock *sk)
1536{
1537	int uid;
1538
1539	read_lock_bh(&sk->sk_callback_lock);
1540	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1541	read_unlock_bh(&sk->sk_callback_lock);
1542	return uid;
1543}
1544EXPORT_SYMBOL(sock_i_uid);
1545
1546unsigned long sock_i_ino(struct sock *sk)
1547{
1548	unsigned long ino;
1549
1550	read_lock_bh(&sk->sk_callback_lock);
1551	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1552	read_unlock_bh(&sk->sk_callback_lock);
1553	return ino;
1554}
1555EXPORT_SYMBOL(sock_i_ino);
1556
1557/*
1558 * Allocate a skb from the socket's send buffer.
1559 */
1560struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1561			     gfp_t priority)
1562{
1563	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1564		struct sk_buff *skb = alloc_skb(size, priority);
1565		if (skb) {
1566			skb_set_owner_w(skb, sk);
1567			return skb;
1568		}
1569	}
1570	return NULL;
1571}
1572EXPORT_SYMBOL(sock_wmalloc);
1573
1574/*
1575 * Allocate a skb from the socket's receive buffer.
1576 */
1577struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1578			     gfp_t priority)
1579{
1580	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1581		struct sk_buff *skb = alloc_skb(size, priority);
1582		if (skb) {
1583			skb_set_owner_r(skb, sk);
1584			return skb;
1585		}
1586	}
1587	return NULL;
1588}
1589
1590/*
1591 * Allocate a memory block from the socket's option memory buffer.
1592 */
1593void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1594{
1595	if ((unsigned int)size <= sysctl_optmem_max &&
1596	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1597		void *mem;
1598		/* First do the add, to avoid the race if kmalloc
1599		 * might sleep.
1600		 */
1601		atomic_add(size, &sk->sk_omem_alloc);
1602		mem = kmalloc(size, priority);
1603		if (mem)
1604			return mem;
1605		atomic_sub(size, &sk->sk_omem_alloc);
1606	}
1607	return NULL;
1608}
1609EXPORT_SYMBOL(sock_kmalloc);
1610
1611/*
1612 * Free an option memory block.
1613 */
1614void sock_kfree_s(struct sock *sk, void *mem, int size)
1615{
1616	kfree(mem);
1617	atomic_sub(size, &sk->sk_omem_alloc);
1618}
1619EXPORT_SYMBOL(sock_kfree_s);
1620
1621/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1622   I think, these locks should be removed for datagram sockets.
1623 */
1624static long sock_wait_for_wmem(struct sock *sk, long timeo)
1625{
1626	DEFINE_WAIT(wait);
1627
1628	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1629	for (;;) {
1630		if (!timeo)
1631			break;
1632		if (signal_pending(current))
1633			break;
1634		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1635		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1636		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1637			break;
1638		if (sk->sk_shutdown & SEND_SHUTDOWN)
1639			break;
1640		if (sk->sk_err)
1641			break;
1642		timeo = schedule_timeout(timeo);
1643	}
1644	finish_wait(sk_sleep(sk), &wait);
1645	return timeo;
1646}
1647
1648
1649/*
1650 *	Generic send/receive buffer handlers
1651 */
1652
1653struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1654				     unsigned long data_len, int noblock,
1655				     int *errcode)
1656{
1657	struct sk_buff *skb;
1658	gfp_t gfp_mask;
1659	long timeo;
1660	int err;
1661	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1662
1663	err = -EMSGSIZE;
1664	if (npages > MAX_SKB_FRAGS)
1665		goto failure;
1666
1667	gfp_mask = sk->sk_allocation;
1668	if (gfp_mask & __GFP_WAIT)
1669		gfp_mask |= __GFP_REPEAT;
1670
1671	timeo = sock_sndtimeo(sk, noblock);
1672	while (1) {
1673		err = sock_error(sk);
1674		if (err != 0)
1675			goto failure;
1676
1677		err = -EPIPE;
1678		if (sk->sk_shutdown & SEND_SHUTDOWN)
1679			goto failure;
1680
1681		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1682			skb = alloc_skb(header_len, gfp_mask);
1683			if (skb) {
1684				int i;
1685
1686				/* No pages, we're done... */
1687				if (!data_len)
1688					break;
1689
1690				skb->truesize += data_len;
1691				skb_shinfo(skb)->nr_frags = npages;
1692				for (i = 0; i < npages; i++) {
1693					struct page *page;
1694
1695					page = alloc_pages(sk->sk_allocation, 0);
1696					if (!page) {
1697						err = -ENOBUFS;
1698						skb_shinfo(skb)->nr_frags = i;
1699						kfree_skb(skb);
1700						goto failure;
1701					}
1702
1703					__skb_fill_page_desc(skb, i,
1704							page, 0,
1705							(data_len >= PAGE_SIZE ?
1706							 PAGE_SIZE :
1707							 data_len));
1708					data_len -= PAGE_SIZE;
1709				}
1710
1711				/* Full success... */
1712				break;
1713			}
1714			err = -ENOBUFS;
1715			goto failure;
1716		}
1717		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1718		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1719		err = -EAGAIN;
1720		if (!timeo)
1721			goto failure;
1722		if (signal_pending(current))
1723			goto interrupted;
1724		timeo = sock_wait_for_wmem(sk, timeo);
1725	}
1726
1727	skb_set_owner_w(skb, sk);
1728	return skb;
1729
1730interrupted:
1731	err = sock_intr_errno(timeo);
1732failure:
1733	*errcode = err;
1734	return NULL;
1735}
1736EXPORT_SYMBOL(sock_alloc_send_pskb);
1737
1738struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1739				    int noblock, int *errcode)
1740{
1741	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1742}
1743EXPORT_SYMBOL(sock_alloc_send_skb);
1744
1745static void __lock_sock(struct sock *sk)
1746	__releases(&sk->sk_lock.slock)
1747	__acquires(&sk->sk_lock.slock)
1748{
1749	DEFINE_WAIT(wait);
1750
1751	for (;;) {
1752		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1753					TASK_UNINTERRUPTIBLE);
1754		spin_unlock_bh(&sk->sk_lock.slock);
1755		schedule();
1756		spin_lock_bh(&sk->sk_lock.slock);
1757		if (!sock_owned_by_user(sk))
1758			break;
1759	}
1760	finish_wait(&sk->sk_lock.wq, &wait);
1761}
1762
1763static void __release_sock(struct sock *sk)
1764	__releases(&sk->sk_lock.slock)
1765	__acquires(&sk->sk_lock.slock)
1766{
1767	struct sk_buff *skb = sk->sk_backlog.head;
1768
1769	do {
1770		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1771		bh_unlock_sock(sk);
1772
1773		do {
1774			struct sk_buff *next = skb->next;
1775
1776			prefetch(next);
1777			WARN_ON_ONCE(skb_dst_is_noref(skb));
1778			skb->next = NULL;
1779			sk_backlog_rcv(sk, skb);
1780
1781			/*
1782			 * We are in process context here with softirqs
1783			 * disabled, use cond_resched_softirq() to preempt.
1784			 * This is safe to do because we've taken the backlog
1785			 * queue private:
1786			 */
1787			cond_resched_softirq();
1788
1789			skb = next;
1790		} while (skb != NULL);
1791
1792		bh_lock_sock(sk);
1793	} while ((skb = sk->sk_backlog.head) != NULL);
1794
1795	/*
1796	 * Doing the zeroing here guarantee we can not loop forever
1797	 * while a wild producer attempts to flood us.
1798	 */
1799	sk->sk_backlog.len = 0;
1800}
1801
1802/**
1803 * sk_wait_data - wait for data to arrive at sk_receive_queue
1804 * @sk:    sock to wait on
1805 * @timeo: for how long
1806 *
1807 * Now socket state including sk->sk_err is changed only under lock,
1808 * hence we may omit checks after joining wait queue.
1809 * We check receive queue before schedule() only as optimization;
1810 * it is very likely that release_sock() added new data.
1811 */
1812int sk_wait_data(struct sock *sk, long *timeo)
1813{
1814	int rc;
1815	DEFINE_WAIT(wait);
1816
1817	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1818	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1819	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1820	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1821	finish_wait(sk_sleep(sk), &wait);
1822	return rc;
1823}
1824EXPORT_SYMBOL(sk_wait_data);
1825
1826/**
1827 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1828 *	@sk: socket
1829 *	@size: memory size to allocate
1830 *	@kind: allocation type
1831 *
1832 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1833 *	rmem allocation. This function assumes that protocols which have
1834 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1835 */
1836int __sk_mem_schedule(struct sock *sk, int size, int kind)
1837{
1838	struct proto *prot = sk->sk_prot;
1839	int amt = sk_mem_pages(size);
1840	long allocated;
1841	int parent_status = UNDER_LIMIT;
1842
1843	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1844
1845	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1846
1847	/* Under limit. */
1848	if (parent_status == UNDER_LIMIT &&
1849			allocated <= sk_prot_mem_limits(sk, 0)) {
1850		sk_leave_memory_pressure(sk);
1851		return 1;
1852	}
1853
1854	/* Under pressure. (we or our parents) */
1855	if ((parent_status > SOFT_LIMIT) ||
1856			allocated > sk_prot_mem_limits(sk, 1))
1857		sk_enter_memory_pressure(sk);
1858
1859	/* Over hard limit (we or our parents) */
1860	if ((parent_status == OVER_LIMIT) ||
1861			(allocated > sk_prot_mem_limits(sk, 2)))
1862		goto suppress_allocation;
1863
1864	/* guarantee minimum buffer size under pressure */
1865	if (kind == SK_MEM_RECV) {
1866		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1867			return 1;
1868
1869	} else { /* SK_MEM_SEND */
1870		if (sk->sk_type == SOCK_STREAM) {
1871			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1872				return 1;
1873		} else if (atomic_read(&sk->sk_wmem_alloc) <
1874			   prot->sysctl_wmem[0])
1875				return 1;
1876	}
1877
1878	if (sk_has_memory_pressure(sk)) {
1879		int alloc;
1880
1881		if (!sk_under_memory_pressure(sk))
1882			return 1;
1883		alloc = sk_sockets_allocated_read_positive(sk);
1884		if (sk_prot_mem_limits(sk, 2) > alloc *
1885		    sk_mem_pages(sk->sk_wmem_queued +
1886				 atomic_read(&sk->sk_rmem_alloc) +
1887				 sk->sk_forward_alloc))
1888			return 1;
1889	}
1890
1891suppress_allocation:
1892
1893	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1894		sk_stream_moderate_sndbuf(sk);
1895
1896		/* Fail only if socket is _under_ its sndbuf.
1897		 * In this case we cannot block, so that we have to fail.
1898		 */
1899		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1900			return 1;
1901	}
1902
1903	trace_sock_exceed_buf_limit(sk, prot, allocated);
1904
1905	/* Alas. Undo changes. */
1906	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1907
1908	sk_memory_allocated_sub(sk, amt);
1909
1910	return 0;
1911}
1912EXPORT_SYMBOL(__sk_mem_schedule);
1913
1914/**
1915 *	__sk_reclaim - reclaim memory_allocated
1916 *	@sk: socket
1917 */
1918void __sk_mem_reclaim(struct sock *sk)
1919{
1920	sk_memory_allocated_sub(sk,
1921				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
1922	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1923
1924	if (sk_under_memory_pressure(sk) &&
1925	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
1926		sk_leave_memory_pressure(sk);
1927}
1928EXPORT_SYMBOL(__sk_mem_reclaim);
1929
1930
1931/*
1932 * Set of default routines for initialising struct proto_ops when
1933 * the protocol does not support a particular function. In certain
1934 * cases where it makes no sense for a protocol to have a "do nothing"
1935 * function, some default processing is provided.
1936 */
1937
1938int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1939{
1940	return -EOPNOTSUPP;
1941}
1942EXPORT_SYMBOL(sock_no_bind);
1943
1944int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1945		    int len, int flags)
1946{
1947	return -EOPNOTSUPP;
1948}
1949EXPORT_SYMBOL(sock_no_connect);
1950
1951int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1952{
1953	return -EOPNOTSUPP;
1954}
1955EXPORT_SYMBOL(sock_no_socketpair);
1956
1957int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1958{
1959	return -EOPNOTSUPP;
1960}
1961EXPORT_SYMBOL(sock_no_accept);
1962
1963int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1964		    int *len, int peer)
1965{
1966	return -EOPNOTSUPP;
1967}
1968EXPORT_SYMBOL(sock_no_getname);
1969
1970unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1971{
1972	return 0;
1973}
1974EXPORT_SYMBOL(sock_no_poll);
1975
1976int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1977{
1978	return -EOPNOTSUPP;
1979}
1980EXPORT_SYMBOL(sock_no_ioctl);
1981
1982int sock_no_listen(struct socket *sock, int backlog)
1983{
1984	return -EOPNOTSUPP;
1985}
1986EXPORT_SYMBOL(sock_no_listen);
1987
1988int sock_no_shutdown(struct socket *sock, int how)
1989{
1990	return -EOPNOTSUPP;
1991}
1992EXPORT_SYMBOL(sock_no_shutdown);
1993
1994int sock_no_setsockopt(struct socket *sock, int level, int optname,
1995		    char __user *optval, unsigned int optlen)
1996{
1997	return -EOPNOTSUPP;
1998}
1999EXPORT_SYMBOL(sock_no_setsockopt);
2000
2001int sock_no_getsockopt(struct socket *sock, int level, int optname,
2002		    char __user *optval, int __user *optlen)
2003{
2004	return -EOPNOTSUPP;
2005}
2006EXPORT_SYMBOL(sock_no_getsockopt);
2007
2008int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2009		    size_t len)
2010{
2011	return -EOPNOTSUPP;
2012}
2013EXPORT_SYMBOL(sock_no_sendmsg);
2014
2015int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2016		    size_t len, int flags)
2017{
2018	return -EOPNOTSUPP;
2019}
2020EXPORT_SYMBOL(sock_no_recvmsg);
2021
2022int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2023{
2024	/* Mirror missing mmap method error code */
2025	return -ENODEV;
2026}
2027EXPORT_SYMBOL(sock_no_mmap);
2028
2029ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2030{
2031	ssize_t res;
2032	struct msghdr msg = {.msg_flags = flags};
2033	struct kvec iov;
2034	char *kaddr = kmap(page);
2035	iov.iov_base = kaddr + offset;
2036	iov.iov_len = size;
2037	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2038	kunmap(page);
2039	return res;
2040}
2041EXPORT_SYMBOL(sock_no_sendpage);
2042
2043/*
2044 *	Default Socket Callbacks
2045 */
2046
2047static void sock_def_wakeup(struct sock *sk)
2048{
2049	struct socket_wq *wq;
2050
2051	rcu_read_lock();
2052	wq = rcu_dereference(sk->sk_wq);
2053	if (wq_has_sleeper(wq))
2054		wake_up_interruptible_all(&wq->wait);
2055	rcu_read_unlock();
2056}
2057
2058static void sock_def_error_report(struct sock *sk)
2059{
2060	struct socket_wq *wq;
2061
2062	rcu_read_lock();
2063	wq = rcu_dereference(sk->sk_wq);
2064	if (wq_has_sleeper(wq))
2065		wake_up_interruptible_poll(&wq->wait, POLLERR);
2066	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2067	rcu_read_unlock();
2068}
2069
2070static void sock_def_readable(struct sock *sk, int len)
2071{
2072	struct socket_wq *wq;
2073
2074	rcu_read_lock();
2075	wq = rcu_dereference(sk->sk_wq);
2076	if (wq_has_sleeper(wq))
2077		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2078						POLLRDNORM | POLLRDBAND);
2079	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2080	rcu_read_unlock();
2081}
2082
2083static void sock_def_write_space(struct sock *sk)
2084{
2085	struct socket_wq *wq;
2086
2087	rcu_read_lock();
2088
2089	/* Do not wake up a writer until he can make "significant"
2090	 * progress.  --DaveM
2091	 */
2092	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2093		wq = rcu_dereference(sk->sk_wq);
2094		if (wq_has_sleeper(wq))
2095			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2096						POLLWRNORM | POLLWRBAND);
2097
2098		/* Should agree with poll, otherwise some programs break */
2099		if (sock_writeable(sk))
2100			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2101	}
2102
2103	rcu_read_unlock();
2104}
2105
2106static void sock_def_destruct(struct sock *sk)
2107{
2108	kfree(sk->sk_protinfo);
2109}
2110
2111void sk_send_sigurg(struct sock *sk)
2112{
2113	if (sk->sk_socket && sk->sk_socket->file)
2114		if (send_sigurg(&sk->sk_socket->file->f_owner))
2115			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2116}
2117EXPORT_SYMBOL(sk_send_sigurg);
2118
2119void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2120		    unsigned long expires)
2121{
2122	if (!mod_timer(timer, expires))
2123		sock_hold(sk);
2124}
2125EXPORT_SYMBOL(sk_reset_timer);
2126
2127void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2128{
2129	if (timer_pending(timer) && del_timer(timer))
2130		__sock_put(sk);
2131}
2132EXPORT_SYMBOL(sk_stop_timer);
2133
2134void sock_init_data(struct socket *sock, struct sock *sk)
2135{
2136	skb_queue_head_init(&sk->sk_receive_queue);
2137	skb_queue_head_init(&sk->sk_write_queue);
2138	skb_queue_head_init(&sk->sk_error_queue);
2139#ifdef CONFIG_NET_DMA
2140	skb_queue_head_init(&sk->sk_async_wait_queue);
2141#endif
2142
2143	sk->sk_send_head	=	NULL;
2144
2145	init_timer(&sk->sk_timer);
2146
2147	sk->sk_allocation	=	GFP_KERNEL;
2148	sk->sk_rcvbuf		=	sysctl_rmem_default;
2149	sk->sk_sndbuf		=	sysctl_wmem_default;
2150	sk->sk_state		=	TCP_CLOSE;
2151	sk_set_socket(sk, sock);
2152
2153	sock_set_flag(sk, SOCK_ZAPPED);
2154
2155	if (sock) {
2156		sk->sk_type	=	sock->type;
2157		sk->sk_wq	=	sock->wq;
2158		sock->sk	=	sk;
2159	} else
2160		sk->sk_wq	=	NULL;
2161
2162	spin_lock_init(&sk->sk_dst_lock);
2163	rwlock_init(&sk->sk_callback_lock);
2164	lockdep_set_class_and_name(&sk->sk_callback_lock,
2165			af_callback_keys + sk->sk_family,
2166			af_family_clock_key_strings[sk->sk_family]);
2167
2168	sk->sk_state_change	=	sock_def_wakeup;
2169	sk->sk_data_ready	=	sock_def_readable;
2170	sk->sk_write_space	=	sock_def_write_space;
2171	sk->sk_error_report	=	sock_def_error_report;
2172	sk->sk_destruct		=	sock_def_destruct;
2173
2174	sk->sk_sndmsg_page	=	NULL;
2175	sk->sk_sndmsg_off	=	0;
2176	sk->sk_peek_off		=	-1;
2177
2178	sk->sk_peer_pid 	=	NULL;
2179	sk->sk_peer_cred	=	NULL;
2180	sk->sk_write_pending	=	0;
2181	sk->sk_rcvlowat		=	1;
2182	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2183	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2184
2185	sk->sk_stamp = ktime_set(-1L, 0);
2186
2187	/*
2188	 * Before updating sk_refcnt, we must commit prior changes to memory
2189	 * (Documentation/RCU/rculist_nulls.txt for details)
2190	 */
2191	smp_wmb();
2192	atomic_set(&sk->sk_refcnt, 1);
2193	atomic_set(&sk->sk_drops, 0);
2194}
2195EXPORT_SYMBOL(sock_init_data);
2196
2197void lock_sock_nested(struct sock *sk, int subclass)
2198{
2199	might_sleep();
2200	spin_lock_bh(&sk->sk_lock.slock);
2201	if (sk->sk_lock.owned)
2202		__lock_sock(sk);
2203	sk->sk_lock.owned = 1;
2204	spin_unlock(&sk->sk_lock.slock);
2205	/*
2206	 * The sk_lock has mutex_lock() semantics here:
2207	 */
2208	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2209	local_bh_enable();
2210}
2211EXPORT_SYMBOL(lock_sock_nested);
2212
2213void release_sock(struct sock *sk)
2214{
2215	/*
2216	 * The sk_lock has mutex_unlock() semantics:
2217	 */
2218	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2219
2220	spin_lock_bh(&sk->sk_lock.slock);
2221	if (sk->sk_backlog.tail)
2222		__release_sock(sk);
2223
2224	if (sk->sk_prot->release_cb)
2225		sk->sk_prot->release_cb(sk);
2226
2227	sk->sk_lock.owned = 0;
2228	if (waitqueue_active(&sk->sk_lock.wq))
2229		wake_up(&sk->sk_lock.wq);
2230	spin_unlock_bh(&sk->sk_lock.slock);
2231}
2232EXPORT_SYMBOL(release_sock);
2233
2234/**
2235 * lock_sock_fast - fast version of lock_sock
2236 * @sk: socket
2237 *
2238 * This version should be used for very small section, where process wont block
2239 * return false if fast path is taken
2240 *   sk_lock.slock locked, owned = 0, BH disabled
2241 * return true if slow path is taken
2242 *   sk_lock.slock unlocked, owned = 1, BH enabled
2243 */
2244bool lock_sock_fast(struct sock *sk)
2245{
2246	might_sleep();
2247	spin_lock_bh(&sk->sk_lock.slock);
2248
2249	if (!sk->sk_lock.owned)
2250		/*
2251		 * Note : We must disable BH
2252		 */
2253		return false;
2254
2255	__lock_sock(sk);
2256	sk->sk_lock.owned = 1;
2257	spin_unlock(&sk->sk_lock.slock);
2258	/*
2259	 * The sk_lock has mutex_lock() semantics here:
2260	 */
2261	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2262	local_bh_enable();
2263	return true;
2264}
2265EXPORT_SYMBOL(lock_sock_fast);
2266
2267int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2268{
2269	struct timeval tv;
2270	if (!sock_flag(sk, SOCK_TIMESTAMP))
2271		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2272	tv = ktime_to_timeval(sk->sk_stamp);
2273	if (tv.tv_sec == -1)
2274		return -ENOENT;
2275	if (tv.tv_sec == 0) {
2276		sk->sk_stamp = ktime_get_real();
2277		tv = ktime_to_timeval(sk->sk_stamp);
2278	}
2279	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2280}
2281EXPORT_SYMBOL(sock_get_timestamp);
2282
2283int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2284{
2285	struct timespec ts;
2286	if (!sock_flag(sk, SOCK_TIMESTAMP))
2287		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2288	ts = ktime_to_timespec(sk->sk_stamp);
2289	if (ts.tv_sec == -1)
2290		return -ENOENT;
2291	if (ts.tv_sec == 0) {
2292		sk->sk_stamp = ktime_get_real();
2293		ts = ktime_to_timespec(sk->sk_stamp);
2294	}
2295	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2296}
2297EXPORT_SYMBOL(sock_get_timestampns);
2298
2299void sock_enable_timestamp(struct sock *sk, int flag)
2300{
2301	if (!sock_flag(sk, flag)) {
2302		unsigned long previous_flags = sk->sk_flags;
2303
2304		sock_set_flag(sk, flag);
2305		/*
2306		 * we just set one of the two flags which require net
2307		 * time stamping, but time stamping might have been on
2308		 * already because of the other one
2309		 */
2310		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2311			net_enable_timestamp();
2312	}
2313}
2314
2315/*
2316 *	Get a socket option on an socket.
2317 *
2318 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2319 *	asynchronous errors should be reported by getsockopt. We assume
2320 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2321 */
2322int sock_common_getsockopt(struct socket *sock, int level, int optname,
2323			   char __user *optval, int __user *optlen)
2324{
2325	struct sock *sk = sock->sk;
2326
2327	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2328}
2329EXPORT_SYMBOL(sock_common_getsockopt);
2330
2331#ifdef CONFIG_COMPAT
2332int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2333				  char __user *optval, int __user *optlen)
2334{
2335	struct sock *sk = sock->sk;
2336
2337	if (sk->sk_prot->compat_getsockopt != NULL)
2338		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2339						      optval, optlen);
2340	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2341}
2342EXPORT_SYMBOL(compat_sock_common_getsockopt);
2343#endif
2344
2345int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2346			struct msghdr *msg, size_t size, int flags)
2347{
2348	struct sock *sk = sock->sk;
2349	int addr_len = 0;
2350	int err;
2351
2352	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2353				   flags & ~MSG_DONTWAIT, &addr_len);
2354	if (err >= 0)
2355		msg->msg_namelen = addr_len;
2356	return err;
2357}
2358EXPORT_SYMBOL(sock_common_recvmsg);
2359
2360/*
2361 *	Set socket options on an inet socket.
2362 */
2363int sock_common_setsockopt(struct socket *sock, int level, int optname,
2364			   char __user *optval, unsigned int optlen)
2365{
2366	struct sock *sk = sock->sk;
2367
2368	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2369}
2370EXPORT_SYMBOL(sock_common_setsockopt);
2371
2372#ifdef CONFIG_COMPAT
2373int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2374				  char __user *optval, unsigned int optlen)
2375{
2376	struct sock *sk = sock->sk;
2377
2378	if (sk->sk_prot->compat_setsockopt != NULL)
2379		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2380						      optval, optlen);
2381	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2382}
2383EXPORT_SYMBOL(compat_sock_common_setsockopt);
2384#endif
2385
2386void sk_common_release(struct sock *sk)
2387{
2388	if (sk->sk_prot->destroy)
2389		sk->sk_prot->destroy(sk);
2390
2391	/*
2392	 * Observation: when sock_common_release is called, processes have
2393	 * no access to socket. But net still has.
2394	 * Step one, detach it from networking:
2395	 *
2396	 * A. Remove from hash tables.
2397	 */
2398
2399	sk->sk_prot->unhash(sk);
2400
2401	/*
2402	 * In this point socket cannot receive new packets, but it is possible
2403	 * that some packets are in flight because some CPU runs receiver and
2404	 * did hash table lookup before we unhashed socket. They will achieve
2405	 * receive queue and will be purged by socket destructor.
2406	 *
2407	 * Also we still have packets pending on receive queue and probably,
2408	 * our own packets waiting in device queues. sock_destroy will drain
2409	 * receive queue, but transmitted packets will delay socket destruction
2410	 * until the last reference will be released.
2411	 */
2412
2413	sock_orphan(sk);
2414
2415	xfrm_sk_free_policy(sk);
2416
2417	sk_refcnt_debug_release(sk);
2418	sock_put(sk);
2419}
2420EXPORT_SYMBOL(sk_common_release);
2421
2422#ifdef CONFIG_PROC_FS
2423#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2424struct prot_inuse {
2425	int val[PROTO_INUSE_NR];
2426};
2427
2428static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2429
2430#ifdef CONFIG_NET_NS
2431void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2432{
2433	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2434}
2435EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2436
2437int sock_prot_inuse_get(struct net *net, struct proto *prot)
2438{
2439	int cpu, idx = prot->inuse_idx;
2440	int res = 0;
2441
2442	for_each_possible_cpu(cpu)
2443		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2444
2445	return res >= 0 ? res : 0;
2446}
2447EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2448
2449static int __net_init sock_inuse_init_net(struct net *net)
2450{
2451	net->core.inuse = alloc_percpu(struct prot_inuse);
2452	return net->core.inuse ? 0 : -ENOMEM;
2453}
2454
2455static void __net_exit sock_inuse_exit_net(struct net *net)
2456{
2457	free_percpu(net->core.inuse);
2458}
2459
2460static struct pernet_operations net_inuse_ops = {
2461	.init = sock_inuse_init_net,
2462	.exit = sock_inuse_exit_net,
2463};
2464
2465static __init int net_inuse_init(void)
2466{
2467	if (register_pernet_subsys(&net_inuse_ops))
2468		panic("Cannot initialize net inuse counters");
2469
2470	return 0;
2471}
2472
2473core_initcall(net_inuse_init);
2474#else
2475static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2476
2477void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2478{
2479	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2480}
2481EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2482
2483int sock_prot_inuse_get(struct net *net, struct proto *prot)
2484{
2485	int cpu, idx = prot->inuse_idx;
2486	int res = 0;
2487
2488	for_each_possible_cpu(cpu)
2489		res += per_cpu(prot_inuse, cpu).val[idx];
2490
2491	return res >= 0 ? res : 0;
2492}
2493EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2494#endif
2495
2496static void assign_proto_idx(struct proto *prot)
2497{
2498	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2499
2500	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2501		pr_err("PROTO_INUSE_NR exhausted\n");
2502		return;
2503	}
2504
2505	set_bit(prot->inuse_idx, proto_inuse_idx);
2506}
2507
2508static void release_proto_idx(struct proto *prot)
2509{
2510	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2511		clear_bit(prot->inuse_idx, proto_inuse_idx);
2512}
2513#else
2514static inline void assign_proto_idx(struct proto *prot)
2515{
2516}
2517
2518static inline void release_proto_idx(struct proto *prot)
2519{
2520}
2521#endif
2522
2523int proto_register(struct proto *prot, int alloc_slab)
2524{
2525	if (alloc_slab) {
2526		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2527					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2528					NULL);
2529
2530		if (prot->slab == NULL) {
2531			pr_crit("%s: Can't create sock SLAB cache!\n",
2532				prot->name);
2533			goto out;
2534		}
2535
2536		if (prot->rsk_prot != NULL) {
2537			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2538			if (prot->rsk_prot->slab_name == NULL)
2539				goto out_free_sock_slab;
2540
2541			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2542								 prot->rsk_prot->obj_size, 0,
2543								 SLAB_HWCACHE_ALIGN, NULL);
2544
2545			if (prot->rsk_prot->slab == NULL) {
2546				pr_crit("%s: Can't create request sock SLAB cache!\n",
2547					prot->name);
2548				goto out_free_request_sock_slab_name;
2549			}
2550		}
2551
2552		if (prot->twsk_prot != NULL) {
2553			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2554
2555			if (prot->twsk_prot->twsk_slab_name == NULL)
2556				goto out_free_request_sock_slab;
2557
2558			prot->twsk_prot->twsk_slab =
2559				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2560						  prot->twsk_prot->twsk_obj_size,
2561						  0,
2562						  SLAB_HWCACHE_ALIGN |
2563							prot->slab_flags,
2564						  NULL);
2565			if (prot->twsk_prot->twsk_slab == NULL)
2566				goto out_free_timewait_sock_slab_name;
2567		}
2568	}
2569
2570	mutex_lock(&proto_list_mutex);
2571	list_add(&prot->node, &proto_list);
2572	assign_proto_idx(prot);
2573	mutex_unlock(&proto_list_mutex);
2574	return 0;
2575
2576out_free_timewait_sock_slab_name:
2577	kfree(prot->twsk_prot->twsk_slab_name);
2578out_free_request_sock_slab:
2579	if (prot->rsk_prot && prot->rsk_prot->slab) {
2580		kmem_cache_destroy(prot->rsk_prot->slab);
2581		prot->rsk_prot->slab = NULL;
2582	}
2583out_free_request_sock_slab_name:
2584	if (prot->rsk_prot)
2585		kfree(prot->rsk_prot->slab_name);
2586out_free_sock_slab:
2587	kmem_cache_destroy(prot->slab);
2588	prot->slab = NULL;
2589out:
2590	return -ENOBUFS;
2591}
2592EXPORT_SYMBOL(proto_register);
2593
2594void proto_unregister(struct proto *prot)
2595{
2596	mutex_lock(&proto_list_mutex);
2597	release_proto_idx(prot);
2598	list_del(&prot->node);
2599	mutex_unlock(&proto_list_mutex);
2600
2601	if (prot->slab != NULL) {
2602		kmem_cache_destroy(prot->slab);
2603		prot->slab = NULL;
2604	}
2605
2606	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2607		kmem_cache_destroy(prot->rsk_prot->slab);
2608		kfree(prot->rsk_prot->slab_name);
2609		prot->rsk_prot->slab = NULL;
2610	}
2611
2612	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2613		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2614		kfree(prot->twsk_prot->twsk_slab_name);
2615		prot->twsk_prot->twsk_slab = NULL;
2616	}
2617}
2618EXPORT_SYMBOL(proto_unregister);
2619
2620#ifdef CONFIG_PROC_FS
2621static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2622	__acquires(proto_list_mutex)
2623{
2624	mutex_lock(&proto_list_mutex);
2625	return seq_list_start_head(&proto_list, *pos);
2626}
2627
2628static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2629{
2630	return seq_list_next(v, &proto_list, pos);
2631}
2632
2633static void proto_seq_stop(struct seq_file *seq, void *v)
2634	__releases(proto_list_mutex)
2635{
2636	mutex_unlock(&proto_list_mutex);
2637}
2638
2639static char proto_method_implemented(const void *method)
2640{
2641	return method == NULL ? 'n' : 'y';
2642}
2643static long sock_prot_memory_allocated(struct proto *proto)
2644{
2645	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2646}
2647
2648static char *sock_prot_memory_pressure(struct proto *proto)
2649{
2650	return proto->memory_pressure != NULL ?
2651	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2652}
2653
2654static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2655{
2656
2657	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2658			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2659		   proto->name,
2660		   proto->obj_size,
2661		   sock_prot_inuse_get(seq_file_net(seq), proto),
2662		   sock_prot_memory_allocated(proto),
2663		   sock_prot_memory_pressure(proto),
2664		   proto->max_header,
2665		   proto->slab == NULL ? "no" : "yes",
2666		   module_name(proto->owner),
2667		   proto_method_implemented(proto->close),
2668		   proto_method_implemented(proto->connect),
2669		   proto_method_implemented(proto->disconnect),
2670		   proto_method_implemented(proto->accept),
2671		   proto_method_implemented(proto->ioctl),
2672		   proto_method_implemented(proto->init),
2673		   proto_method_implemented(proto->destroy),
2674		   proto_method_implemented(proto->shutdown),
2675		   proto_method_implemented(proto->setsockopt),
2676		   proto_method_implemented(proto->getsockopt),
2677		   proto_method_implemented(proto->sendmsg),
2678		   proto_method_implemented(proto->recvmsg),
2679		   proto_method_implemented(proto->sendpage),
2680		   proto_method_implemented(proto->bind),
2681		   proto_method_implemented(proto->backlog_rcv),
2682		   proto_method_implemented(proto->hash),
2683		   proto_method_implemented(proto->unhash),
2684		   proto_method_implemented(proto->get_port),
2685		   proto_method_implemented(proto->enter_memory_pressure));
2686}
2687
2688static int proto_seq_show(struct seq_file *seq, void *v)
2689{
2690	if (v == &proto_list)
2691		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2692			   "protocol",
2693			   "size",
2694			   "sockets",
2695			   "memory",
2696			   "press",
2697			   "maxhdr",
2698			   "slab",
2699			   "module",
2700			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2701	else
2702		proto_seq_printf(seq, list_entry(v, struct proto, node));
2703	return 0;
2704}
2705
2706static const struct seq_operations proto_seq_ops = {
2707	.start  = proto_seq_start,
2708	.next   = proto_seq_next,
2709	.stop   = proto_seq_stop,
2710	.show   = proto_seq_show,
2711};
2712
2713static int proto_seq_open(struct inode *inode, struct file *file)
2714{
2715	return seq_open_net(inode, file, &proto_seq_ops,
2716			    sizeof(struct seq_net_private));
2717}
2718
2719static const struct file_operations proto_seq_fops = {
2720	.owner		= THIS_MODULE,
2721	.open		= proto_seq_open,
2722	.read		= seq_read,
2723	.llseek		= seq_lseek,
2724	.release	= seq_release_net,
2725};
2726
2727static __net_init int proto_init_net(struct net *net)
2728{
2729	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2730		return -ENOMEM;
2731
2732	return 0;
2733}
2734
2735static __net_exit void proto_exit_net(struct net *net)
2736{
2737	proc_net_remove(net, "protocols");
2738}
2739
2740
2741static __net_initdata struct pernet_operations proto_net_ops = {
2742	.init = proto_init_net,
2743	.exit = proto_exit_net,
2744};
2745
2746static int __init proto_init(void)
2747{
2748	return register_pernet_subsys(&proto_net_ops);
2749}
2750
2751subsys_initcall(proto_init);
2752
2753#endif /* PROC_FS */
2754