sock.c revision b4b9e3558508980fc0cd161a545ffb55a1f13ee9
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}
299EXPORT_SYMBOL_GPL(sk_clear_memalloc);
300
301int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
302{
303	int ret;
304	unsigned long pflags = current->flags;
305
306	/* these should have been dropped before queueing */
307	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
308
309	current->flags |= PF_MEMALLOC;
310	ret = sk->sk_backlog_rcv(sk, skb);
311	tsk_restore_flags(current, pflags, PF_MEMALLOC);
312
313	return ret;
314}
315EXPORT_SYMBOL(__sk_backlog_rcv);
316
317#if defined(CONFIG_CGROUPS)
318#if !defined(CONFIG_NET_CLS_CGROUP)
319int net_cls_subsys_id = -1;
320EXPORT_SYMBOL_GPL(net_cls_subsys_id);
321#endif
322#if !defined(CONFIG_NETPRIO_CGROUP)
323int net_prio_subsys_id = -1;
324EXPORT_SYMBOL_GPL(net_prio_subsys_id);
325#endif
326#endif
327
328static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
329{
330	struct timeval tv;
331
332	if (optlen < sizeof(tv))
333		return -EINVAL;
334	if (copy_from_user(&tv, optval, sizeof(tv)))
335		return -EFAULT;
336	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
337		return -EDOM;
338
339	if (tv.tv_sec < 0) {
340		static int warned __read_mostly;
341
342		*timeo_p = 0;
343		if (warned < 10 && net_ratelimit()) {
344			warned++;
345			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
346				__func__, current->comm, task_pid_nr(current));
347		}
348		return 0;
349	}
350	*timeo_p = MAX_SCHEDULE_TIMEOUT;
351	if (tv.tv_sec == 0 && tv.tv_usec == 0)
352		return 0;
353	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
354		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
355	return 0;
356}
357
358static void sock_warn_obsolete_bsdism(const char *name)
359{
360	static int warned;
361	static char warncomm[TASK_COMM_LEN];
362	if (strcmp(warncomm, current->comm) && warned < 5) {
363		strcpy(warncomm,  current->comm);
364		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
365			warncomm, name);
366		warned++;
367	}
368}
369
370#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
371
372static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
373{
374	if (sk->sk_flags & flags) {
375		sk->sk_flags &= ~flags;
376		if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
377			net_disable_timestamp();
378	}
379}
380
381
382int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
383{
384	int err;
385	int skb_len;
386	unsigned long flags;
387	struct sk_buff_head *list = &sk->sk_receive_queue;
388
389	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
390		atomic_inc(&sk->sk_drops);
391		trace_sock_rcvqueue_full(sk, skb);
392		return -ENOMEM;
393	}
394
395	err = sk_filter(sk, skb);
396	if (err)
397		return err;
398
399	if (!sk_rmem_schedule(sk, skb->truesize)) {
400		atomic_inc(&sk->sk_drops);
401		return -ENOBUFS;
402	}
403
404	skb->dev = NULL;
405	skb_set_owner_r(skb, sk);
406
407	/* Cache the SKB length before we tack it onto the receive
408	 * queue.  Once it is added it no longer belongs to us and
409	 * may be freed by other threads of control pulling packets
410	 * from the queue.
411	 */
412	skb_len = skb->len;
413
414	/* we escape from rcu protected region, make sure we dont leak
415	 * a norefcounted dst
416	 */
417	skb_dst_force(skb);
418
419	spin_lock_irqsave(&list->lock, flags);
420	skb->dropcount = atomic_read(&sk->sk_drops);
421	__skb_queue_tail(list, skb);
422	spin_unlock_irqrestore(&list->lock, flags);
423
424	if (!sock_flag(sk, SOCK_DEAD))
425		sk->sk_data_ready(sk, skb_len);
426	return 0;
427}
428EXPORT_SYMBOL(sock_queue_rcv_skb);
429
430int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
431{
432	int rc = NET_RX_SUCCESS;
433
434	if (sk_filter(sk, skb))
435		goto discard_and_relse;
436
437	skb->dev = NULL;
438
439	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
440		atomic_inc(&sk->sk_drops);
441		goto discard_and_relse;
442	}
443	if (nested)
444		bh_lock_sock_nested(sk);
445	else
446		bh_lock_sock(sk);
447	if (!sock_owned_by_user(sk)) {
448		/*
449		 * trylock + unlock semantics:
450		 */
451		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
452
453		rc = sk_backlog_rcv(sk, skb);
454
455		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
456	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
457		bh_unlock_sock(sk);
458		atomic_inc(&sk->sk_drops);
459		goto discard_and_relse;
460	}
461
462	bh_unlock_sock(sk);
463out:
464	sock_put(sk);
465	return rc;
466discard_and_relse:
467	kfree_skb(skb);
468	goto out;
469}
470EXPORT_SYMBOL(sk_receive_skb);
471
472void sk_reset_txq(struct sock *sk)
473{
474	sk_tx_queue_clear(sk);
475}
476EXPORT_SYMBOL(sk_reset_txq);
477
478struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
479{
480	struct dst_entry *dst = __sk_dst_get(sk);
481
482	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
483		sk_tx_queue_clear(sk);
484		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
485		dst_release(dst);
486		return NULL;
487	}
488
489	return dst;
490}
491EXPORT_SYMBOL(__sk_dst_check);
492
493struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
494{
495	struct dst_entry *dst = sk_dst_get(sk);
496
497	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
498		sk_dst_reset(sk);
499		dst_release(dst);
500		return NULL;
501	}
502
503	return dst;
504}
505EXPORT_SYMBOL(sk_dst_check);
506
507static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
508{
509	int ret = -ENOPROTOOPT;
510#ifdef CONFIG_NETDEVICES
511	struct net *net = sock_net(sk);
512	char devname[IFNAMSIZ];
513	int index;
514
515	/* Sorry... */
516	ret = -EPERM;
517	if (!capable(CAP_NET_RAW))
518		goto out;
519
520	ret = -EINVAL;
521	if (optlen < 0)
522		goto out;
523
524	/* Bind this socket to a particular device like "eth0",
525	 * as specified in the passed interface name. If the
526	 * name is "" or the option length is zero the socket
527	 * is not bound.
528	 */
529	if (optlen > IFNAMSIZ - 1)
530		optlen = IFNAMSIZ - 1;
531	memset(devname, 0, sizeof(devname));
532
533	ret = -EFAULT;
534	if (copy_from_user(devname, optval, optlen))
535		goto out;
536
537	index = 0;
538	if (devname[0] != '\0') {
539		struct net_device *dev;
540
541		rcu_read_lock();
542		dev = dev_get_by_name_rcu(net, devname);
543		if (dev)
544			index = dev->ifindex;
545		rcu_read_unlock();
546		ret = -ENODEV;
547		if (!dev)
548			goto out;
549	}
550
551	lock_sock(sk);
552	sk->sk_bound_dev_if = index;
553	sk_dst_reset(sk);
554	release_sock(sk);
555
556	ret = 0;
557
558out:
559#endif
560
561	return ret;
562}
563
564static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
565{
566	if (valbool)
567		sock_set_flag(sk, bit);
568	else
569		sock_reset_flag(sk, bit);
570}
571
572/*
573 *	This is meant for all protocols to use and covers goings on
574 *	at the socket level. Everything here is generic.
575 */
576
577int sock_setsockopt(struct socket *sock, int level, int optname,
578		    char __user *optval, unsigned int optlen)
579{
580	struct sock *sk = sock->sk;
581	int val;
582	int valbool;
583	struct linger ling;
584	int ret = 0;
585
586	/*
587	 *	Options without arguments
588	 */
589
590	if (optname == SO_BINDTODEVICE)
591		return sock_bindtodevice(sk, optval, optlen);
592
593	if (optlen < sizeof(int))
594		return -EINVAL;
595
596	if (get_user(val, (int __user *)optval))
597		return -EFAULT;
598
599	valbool = val ? 1 : 0;
600
601	lock_sock(sk);
602
603	switch (optname) {
604	case SO_DEBUG:
605		if (val && !capable(CAP_NET_ADMIN))
606			ret = -EACCES;
607		else
608			sock_valbool_flag(sk, SOCK_DBG, valbool);
609		break;
610	case SO_REUSEADDR:
611		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
612		break;
613	case SO_TYPE:
614	case SO_PROTOCOL:
615	case SO_DOMAIN:
616	case SO_ERROR:
617		ret = -ENOPROTOOPT;
618		break;
619	case SO_DONTROUTE:
620		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
621		break;
622	case SO_BROADCAST:
623		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
624		break;
625	case SO_SNDBUF:
626		/* Don't error on this BSD doesn't and if you think
627		 * about it this is right. Otherwise apps have to
628		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
629		 * are treated in BSD as hints
630		 */
631		val = min_t(u32, val, sysctl_wmem_max);
632set_sndbuf:
633		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
634		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
635		/* Wake up sending tasks if we upped the value. */
636		sk->sk_write_space(sk);
637		break;
638
639	case SO_SNDBUFFORCE:
640		if (!capable(CAP_NET_ADMIN)) {
641			ret = -EPERM;
642			break;
643		}
644		goto set_sndbuf;
645
646	case SO_RCVBUF:
647		/* Don't error on this BSD doesn't and if you think
648		 * about it this is right. Otherwise apps have to
649		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
650		 * are treated in BSD as hints
651		 */
652		val = min_t(u32, val, sysctl_rmem_max);
653set_rcvbuf:
654		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
655		/*
656		 * We double it on the way in to account for
657		 * "struct sk_buff" etc. overhead.   Applications
658		 * assume that the SO_RCVBUF setting they make will
659		 * allow that much actual data to be received on that
660		 * socket.
661		 *
662		 * Applications are unaware that "struct sk_buff" and
663		 * other overheads allocate from the receive buffer
664		 * during socket buffer allocation.
665		 *
666		 * And after considering the possible alternatives,
667		 * returning the value we actually used in getsockopt
668		 * is the most desirable behavior.
669		 */
670		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
671		break;
672
673	case SO_RCVBUFFORCE:
674		if (!capable(CAP_NET_ADMIN)) {
675			ret = -EPERM;
676			break;
677		}
678		goto set_rcvbuf;
679
680	case SO_KEEPALIVE:
681#ifdef CONFIG_INET
682		if (sk->sk_protocol == IPPROTO_TCP)
683			tcp_set_keepalive(sk, valbool);
684#endif
685		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
686		break;
687
688	case SO_OOBINLINE:
689		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
690		break;
691
692	case SO_NO_CHECK:
693		sk->sk_no_check = valbool;
694		break;
695
696	case SO_PRIORITY:
697		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
698			sk->sk_priority = val;
699		else
700			ret = -EPERM;
701		break;
702
703	case SO_LINGER:
704		if (optlen < sizeof(ling)) {
705			ret = -EINVAL;	/* 1003.1g */
706			break;
707		}
708		if (copy_from_user(&ling, optval, sizeof(ling))) {
709			ret = -EFAULT;
710			break;
711		}
712		if (!ling.l_onoff)
713			sock_reset_flag(sk, SOCK_LINGER);
714		else {
715#if (BITS_PER_LONG == 32)
716			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
717				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
718			else
719#endif
720				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
721			sock_set_flag(sk, SOCK_LINGER);
722		}
723		break;
724
725	case SO_BSDCOMPAT:
726		sock_warn_obsolete_bsdism("setsockopt");
727		break;
728
729	case SO_PASSCRED:
730		if (valbool)
731			set_bit(SOCK_PASSCRED, &sock->flags);
732		else
733			clear_bit(SOCK_PASSCRED, &sock->flags);
734		break;
735
736	case SO_TIMESTAMP:
737	case SO_TIMESTAMPNS:
738		if (valbool)  {
739			if (optname == SO_TIMESTAMP)
740				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
741			else
742				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
743			sock_set_flag(sk, SOCK_RCVTSTAMP);
744			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
745		} else {
746			sock_reset_flag(sk, SOCK_RCVTSTAMP);
747			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
748		}
749		break;
750
751	case SO_TIMESTAMPING:
752		if (val & ~SOF_TIMESTAMPING_MASK) {
753			ret = -EINVAL;
754			break;
755		}
756		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
757				  val & SOF_TIMESTAMPING_TX_HARDWARE);
758		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
759				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
760		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
761				  val & SOF_TIMESTAMPING_RX_HARDWARE);
762		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
763			sock_enable_timestamp(sk,
764					      SOCK_TIMESTAMPING_RX_SOFTWARE);
765		else
766			sock_disable_timestamp(sk,
767					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
768		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
769				  val & SOF_TIMESTAMPING_SOFTWARE);
770		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
771				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
772		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
773				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
774		break;
775
776	case SO_RCVLOWAT:
777		if (val < 0)
778			val = INT_MAX;
779		sk->sk_rcvlowat = val ? : 1;
780		break;
781
782	case SO_RCVTIMEO:
783		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
784		break;
785
786	case SO_SNDTIMEO:
787		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
788		break;
789
790	case SO_ATTACH_FILTER:
791		ret = -EINVAL;
792		if (optlen == sizeof(struct sock_fprog)) {
793			struct sock_fprog fprog;
794
795			ret = -EFAULT;
796			if (copy_from_user(&fprog, optval, sizeof(fprog)))
797				break;
798
799			ret = sk_attach_filter(&fprog, sk);
800		}
801		break;
802
803	case SO_DETACH_FILTER:
804		ret = sk_detach_filter(sk);
805		break;
806
807	case SO_PASSSEC:
808		if (valbool)
809			set_bit(SOCK_PASSSEC, &sock->flags);
810		else
811			clear_bit(SOCK_PASSSEC, &sock->flags);
812		break;
813	case SO_MARK:
814		if (!capable(CAP_NET_ADMIN))
815			ret = -EPERM;
816		else
817			sk->sk_mark = val;
818		break;
819
820		/* We implement the SO_SNDLOWAT etc to
821		   not be settable (1003.1g 5.3) */
822	case SO_RXQ_OVFL:
823		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
824		break;
825
826	case SO_WIFI_STATUS:
827		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
828		break;
829
830	case SO_PEEK_OFF:
831		if (sock->ops->set_peek_off)
832			sock->ops->set_peek_off(sk, val);
833		else
834			ret = -EOPNOTSUPP;
835		break;
836
837	case SO_NOFCS:
838		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
839		break;
840
841	default:
842		ret = -ENOPROTOOPT;
843		break;
844	}
845	release_sock(sk);
846	return ret;
847}
848EXPORT_SYMBOL(sock_setsockopt);
849
850
851void cred_to_ucred(struct pid *pid, const struct cred *cred,
852		   struct ucred *ucred)
853{
854	ucred->pid = pid_vnr(pid);
855	ucred->uid = ucred->gid = -1;
856	if (cred) {
857		struct user_namespace *current_ns = current_user_ns();
858
859		ucred->uid = from_kuid(current_ns, cred->euid);
860		ucred->gid = from_kgid(current_ns, cred->egid);
861	}
862}
863EXPORT_SYMBOL_GPL(cred_to_ucred);
864
865int sock_getsockopt(struct socket *sock, int level, int optname,
866		    char __user *optval, int __user *optlen)
867{
868	struct sock *sk = sock->sk;
869
870	union {
871		int val;
872		struct linger ling;
873		struct timeval tm;
874	} v;
875
876	int lv = sizeof(int);
877	int len;
878
879	if (get_user(len, optlen))
880		return -EFAULT;
881	if (len < 0)
882		return -EINVAL;
883
884	memset(&v, 0, sizeof(v));
885
886	switch (optname) {
887	case SO_DEBUG:
888		v.val = sock_flag(sk, SOCK_DBG);
889		break;
890
891	case SO_DONTROUTE:
892		v.val = sock_flag(sk, SOCK_LOCALROUTE);
893		break;
894
895	case SO_BROADCAST:
896		v.val = sock_flag(sk, SOCK_BROADCAST);
897		break;
898
899	case SO_SNDBUF:
900		v.val = sk->sk_sndbuf;
901		break;
902
903	case SO_RCVBUF:
904		v.val = sk->sk_rcvbuf;
905		break;
906
907	case SO_REUSEADDR:
908		v.val = sk->sk_reuse;
909		break;
910
911	case SO_KEEPALIVE:
912		v.val = sock_flag(sk, SOCK_KEEPOPEN);
913		break;
914
915	case SO_TYPE:
916		v.val = sk->sk_type;
917		break;
918
919	case SO_PROTOCOL:
920		v.val = sk->sk_protocol;
921		break;
922
923	case SO_DOMAIN:
924		v.val = sk->sk_family;
925		break;
926
927	case SO_ERROR:
928		v.val = -sock_error(sk);
929		if (v.val == 0)
930			v.val = xchg(&sk->sk_err_soft, 0);
931		break;
932
933	case SO_OOBINLINE:
934		v.val = sock_flag(sk, SOCK_URGINLINE);
935		break;
936
937	case SO_NO_CHECK:
938		v.val = sk->sk_no_check;
939		break;
940
941	case SO_PRIORITY:
942		v.val = sk->sk_priority;
943		break;
944
945	case SO_LINGER:
946		lv		= sizeof(v.ling);
947		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
948		v.ling.l_linger	= sk->sk_lingertime / HZ;
949		break;
950
951	case SO_BSDCOMPAT:
952		sock_warn_obsolete_bsdism("getsockopt");
953		break;
954
955	case SO_TIMESTAMP:
956		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
957				!sock_flag(sk, SOCK_RCVTSTAMPNS);
958		break;
959
960	case SO_TIMESTAMPNS:
961		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
962		break;
963
964	case SO_TIMESTAMPING:
965		v.val = 0;
966		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
967			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
968		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
969			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
970		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
971			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
972		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
973			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
974		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
975			v.val |= SOF_TIMESTAMPING_SOFTWARE;
976		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
977			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
978		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
979			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
980		break;
981
982	case SO_RCVTIMEO:
983		lv = sizeof(struct timeval);
984		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
985			v.tm.tv_sec = 0;
986			v.tm.tv_usec = 0;
987		} else {
988			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
989			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
990		}
991		break;
992
993	case SO_SNDTIMEO:
994		lv = sizeof(struct timeval);
995		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
996			v.tm.tv_sec = 0;
997			v.tm.tv_usec = 0;
998		} else {
999			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1000			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1001		}
1002		break;
1003
1004	case SO_RCVLOWAT:
1005		v.val = sk->sk_rcvlowat;
1006		break;
1007
1008	case SO_SNDLOWAT:
1009		v.val = 1;
1010		break;
1011
1012	case SO_PASSCRED:
1013		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1014		break;
1015
1016	case SO_PEERCRED:
1017	{
1018		struct ucred peercred;
1019		if (len > sizeof(peercred))
1020			len = sizeof(peercred);
1021		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1022		if (copy_to_user(optval, &peercred, len))
1023			return -EFAULT;
1024		goto lenout;
1025	}
1026
1027	case SO_PEERNAME:
1028	{
1029		char address[128];
1030
1031		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1032			return -ENOTCONN;
1033		if (lv < len)
1034			return -EINVAL;
1035		if (copy_to_user(optval, address, len))
1036			return -EFAULT;
1037		goto lenout;
1038	}
1039
1040	/* Dubious BSD thing... Probably nobody even uses it, but
1041	 * the UNIX standard wants it for whatever reason... -DaveM
1042	 */
1043	case SO_ACCEPTCONN:
1044		v.val = sk->sk_state == TCP_LISTEN;
1045		break;
1046
1047	case SO_PASSSEC:
1048		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1049		break;
1050
1051	case SO_PEERSEC:
1052		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1053
1054	case SO_MARK:
1055		v.val = sk->sk_mark;
1056		break;
1057
1058	case SO_RXQ_OVFL:
1059		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1060		break;
1061
1062	case SO_WIFI_STATUS:
1063		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1064		break;
1065
1066	case SO_PEEK_OFF:
1067		if (!sock->ops->set_peek_off)
1068			return -EOPNOTSUPP;
1069
1070		v.val = sk->sk_peek_off;
1071		break;
1072	case SO_NOFCS:
1073		v.val = sock_flag(sk, SOCK_NOFCS);
1074		break;
1075	default:
1076		return -ENOPROTOOPT;
1077	}
1078
1079	if (len > lv)
1080		len = lv;
1081	if (copy_to_user(optval, &v, len))
1082		return -EFAULT;
1083lenout:
1084	if (put_user(len, optlen))
1085		return -EFAULT;
1086	return 0;
1087}
1088
1089/*
1090 * Initialize an sk_lock.
1091 *
1092 * (We also register the sk_lock with the lock validator.)
1093 */
1094static inline void sock_lock_init(struct sock *sk)
1095{
1096	sock_lock_init_class_and_name(sk,
1097			af_family_slock_key_strings[sk->sk_family],
1098			af_family_slock_keys + sk->sk_family,
1099			af_family_key_strings[sk->sk_family],
1100			af_family_keys + sk->sk_family);
1101}
1102
1103/*
1104 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1105 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1106 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1107 */
1108static void sock_copy(struct sock *nsk, const struct sock *osk)
1109{
1110#ifdef CONFIG_SECURITY_NETWORK
1111	void *sptr = nsk->sk_security;
1112#endif
1113	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1114
1115	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1116	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1117
1118#ifdef CONFIG_SECURITY_NETWORK
1119	nsk->sk_security = sptr;
1120	security_sk_clone(osk, nsk);
1121#endif
1122}
1123
1124/*
1125 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1126 * un-modified. Special care is taken when initializing object to zero.
1127 */
1128static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1129{
1130	if (offsetof(struct sock, sk_node.next) != 0)
1131		memset(sk, 0, offsetof(struct sock, sk_node.next));
1132	memset(&sk->sk_node.pprev, 0,
1133	       size - offsetof(struct sock, sk_node.pprev));
1134}
1135
1136void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1137{
1138	unsigned long nulls1, nulls2;
1139
1140	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1141	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1142	if (nulls1 > nulls2)
1143		swap(nulls1, nulls2);
1144
1145	if (nulls1 != 0)
1146		memset((char *)sk, 0, nulls1);
1147	memset((char *)sk + nulls1 + sizeof(void *), 0,
1148	       nulls2 - nulls1 - sizeof(void *));
1149	memset((char *)sk + nulls2 + sizeof(void *), 0,
1150	       size - nulls2 - sizeof(void *));
1151}
1152EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1153
1154static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1155		int family)
1156{
1157	struct sock *sk;
1158	struct kmem_cache *slab;
1159
1160	slab = prot->slab;
1161	if (slab != NULL) {
1162		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1163		if (!sk)
1164			return sk;
1165		if (priority & __GFP_ZERO) {
1166			if (prot->clear_sk)
1167				prot->clear_sk(sk, prot->obj_size);
1168			else
1169				sk_prot_clear_nulls(sk, prot->obj_size);
1170		}
1171	} else
1172		sk = kmalloc(prot->obj_size, priority);
1173
1174	if (sk != NULL) {
1175		kmemcheck_annotate_bitfield(sk, flags);
1176
1177		if (security_sk_alloc(sk, family, priority))
1178			goto out_free;
1179
1180		if (!try_module_get(prot->owner))
1181			goto out_free_sec;
1182		sk_tx_queue_clear(sk);
1183	}
1184
1185	return sk;
1186
1187out_free_sec:
1188	security_sk_free(sk);
1189out_free:
1190	if (slab != NULL)
1191		kmem_cache_free(slab, sk);
1192	else
1193		kfree(sk);
1194	return NULL;
1195}
1196
1197static void sk_prot_free(struct proto *prot, struct sock *sk)
1198{
1199	struct kmem_cache *slab;
1200	struct module *owner;
1201
1202	owner = prot->owner;
1203	slab = prot->slab;
1204
1205	security_sk_free(sk);
1206	if (slab != NULL)
1207		kmem_cache_free(slab, sk);
1208	else
1209		kfree(sk);
1210	module_put(owner);
1211}
1212
1213#ifdef CONFIG_CGROUPS
1214void sock_update_classid(struct sock *sk)
1215{
1216	u32 classid;
1217
1218	rcu_read_lock();  /* doing current task, which cannot vanish. */
1219	classid = task_cls_classid(current);
1220	rcu_read_unlock();
1221	if (classid && classid != sk->sk_classid)
1222		sk->sk_classid = classid;
1223}
1224EXPORT_SYMBOL(sock_update_classid);
1225
1226void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
1227{
1228	if (in_interrupt())
1229		return;
1230
1231	sk->sk_cgrp_prioidx = task_netprioidx(task);
1232}
1233EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1234#endif
1235
1236/**
1237 *	sk_alloc - All socket objects are allocated here
1238 *	@net: the applicable net namespace
1239 *	@family: protocol family
1240 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1241 *	@prot: struct proto associated with this new sock instance
1242 */
1243struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1244		      struct proto *prot)
1245{
1246	struct sock *sk;
1247
1248	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1249	if (sk) {
1250		sk->sk_family = family;
1251		/*
1252		 * See comment in struct sock definition to understand
1253		 * why we need sk_prot_creator -acme
1254		 */
1255		sk->sk_prot = sk->sk_prot_creator = prot;
1256		sock_lock_init(sk);
1257		sock_net_set(sk, get_net(net));
1258		atomic_set(&sk->sk_wmem_alloc, 1);
1259
1260		sock_update_classid(sk);
1261		sock_update_netprioidx(sk, current);
1262	}
1263
1264	return sk;
1265}
1266EXPORT_SYMBOL(sk_alloc);
1267
1268static void __sk_free(struct sock *sk)
1269{
1270	struct sk_filter *filter;
1271
1272	if (sk->sk_destruct)
1273		sk->sk_destruct(sk);
1274
1275	filter = rcu_dereference_check(sk->sk_filter,
1276				       atomic_read(&sk->sk_wmem_alloc) == 0);
1277	if (filter) {
1278		sk_filter_uncharge(sk, filter);
1279		RCU_INIT_POINTER(sk->sk_filter, NULL);
1280	}
1281
1282	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1283
1284	if (atomic_read(&sk->sk_omem_alloc))
1285		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1286			 __func__, atomic_read(&sk->sk_omem_alloc));
1287
1288	if (sk->sk_peer_cred)
1289		put_cred(sk->sk_peer_cred);
1290	put_pid(sk->sk_peer_pid);
1291	put_net(sock_net(sk));
1292	sk_prot_free(sk->sk_prot_creator, sk);
1293}
1294
1295void sk_free(struct sock *sk)
1296{
1297	/*
1298	 * We subtract one from sk_wmem_alloc and can know if
1299	 * some packets are still in some tx queue.
1300	 * If not null, sock_wfree() will call __sk_free(sk) later
1301	 */
1302	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1303		__sk_free(sk);
1304}
1305EXPORT_SYMBOL(sk_free);
1306
1307/*
1308 * Last sock_put should drop reference to sk->sk_net. It has already
1309 * been dropped in sk_change_net. Taking reference to stopping namespace
1310 * is not an option.
1311 * Take reference to a socket to remove it from hash _alive_ and after that
1312 * destroy it in the context of init_net.
1313 */
1314void sk_release_kernel(struct sock *sk)
1315{
1316	if (sk == NULL || sk->sk_socket == NULL)
1317		return;
1318
1319	sock_hold(sk);
1320	sock_release(sk->sk_socket);
1321	release_net(sock_net(sk));
1322	sock_net_set(sk, get_net(&init_net));
1323	sock_put(sk);
1324}
1325EXPORT_SYMBOL(sk_release_kernel);
1326
1327static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1328{
1329	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1330		sock_update_memcg(newsk);
1331}
1332
1333/**
1334 *	sk_clone_lock - clone a socket, and lock its clone
1335 *	@sk: the socket to clone
1336 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1337 *
1338 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1339 */
1340struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1341{
1342	struct sock *newsk;
1343
1344	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1345	if (newsk != NULL) {
1346		struct sk_filter *filter;
1347
1348		sock_copy(newsk, sk);
1349
1350		/* SANITY */
1351		get_net(sock_net(newsk));
1352		sk_node_init(&newsk->sk_node);
1353		sock_lock_init(newsk);
1354		bh_lock_sock(newsk);
1355		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1356		newsk->sk_backlog.len = 0;
1357
1358		atomic_set(&newsk->sk_rmem_alloc, 0);
1359		/*
1360		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1361		 */
1362		atomic_set(&newsk->sk_wmem_alloc, 1);
1363		atomic_set(&newsk->sk_omem_alloc, 0);
1364		skb_queue_head_init(&newsk->sk_receive_queue);
1365		skb_queue_head_init(&newsk->sk_write_queue);
1366#ifdef CONFIG_NET_DMA
1367		skb_queue_head_init(&newsk->sk_async_wait_queue);
1368#endif
1369
1370		spin_lock_init(&newsk->sk_dst_lock);
1371		rwlock_init(&newsk->sk_callback_lock);
1372		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1373				af_callback_keys + newsk->sk_family,
1374				af_family_clock_key_strings[newsk->sk_family]);
1375
1376		newsk->sk_dst_cache	= NULL;
1377		newsk->sk_wmem_queued	= 0;
1378		newsk->sk_forward_alloc = 0;
1379		newsk->sk_send_head	= NULL;
1380		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1381
1382		sock_reset_flag(newsk, SOCK_DONE);
1383		skb_queue_head_init(&newsk->sk_error_queue);
1384
1385		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1386		if (filter != NULL)
1387			sk_filter_charge(newsk, filter);
1388
1389		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1390			/* It is still raw copy of parent, so invalidate
1391			 * destructor and make plain sk_free() */
1392			newsk->sk_destruct = NULL;
1393			bh_unlock_sock(newsk);
1394			sk_free(newsk);
1395			newsk = NULL;
1396			goto out;
1397		}
1398
1399		newsk->sk_err	   = 0;
1400		newsk->sk_priority = 0;
1401		/*
1402		 * Before updating sk_refcnt, we must commit prior changes to memory
1403		 * (Documentation/RCU/rculist_nulls.txt for details)
1404		 */
1405		smp_wmb();
1406		atomic_set(&newsk->sk_refcnt, 2);
1407
1408		/*
1409		 * Increment the counter in the same struct proto as the master
1410		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1411		 * is the same as sk->sk_prot->socks, as this field was copied
1412		 * with memcpy).
1413		 *
1414		 * This _changes_ the previous behaviour, where
1415		 * tcp_create_openreq_child always was incrementing the
1416		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1417		 * to be taken into account in all callers. -acme
1418		 */
1419		sk_refcnt_debug_inc(newsk);
1420		sk_set_socket(newsk, NULL);
1421		newsk->sk_wq = NULL;
1422
1423		sk_update_clone(sk, newsk);
1424
1425		if (newsk->sk_prot->sockets_allocated)
1426			sk_sockets_allocated_inc(newsk);
1427
1428		if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1429			net_enable_timestamp();
1430	}
1431out:
1432	return newsk;
1433}
1434EXPORT_SYMBOL_GPL(sk_clone_lock);
1435
1436void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1437{
1438	__sk_dst_set(sk, dst);
1439	sk->sk_route_caps = dst->dev->features;
1440	if (sk->sk_route_caps & NETIF_F_GSO)
1441		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1442	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1443	if (sk_can_gso(sk)) {
1444		if (dst->header_len) {
1445			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1446		} else {
1447			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1448			sk->sk_gso_max_size = dst->dev->gso_max_size;
1449		}
1450	}
1451}
1452EXPORT_SYMBOL_GPL(sk_setup_caps);
1453
1454void __init sk_init(void)
1455{
1456	if (totalram_pages <= 4096) {
1457		sysctl_wmem_max = 32767;
1458		sysctl_rmem_max = 32767;
1459		sysctl_wmem_default = 32767;
1460		sysctl_rmem_default = 32767;
1461	} else if (totalram_pages >= 131072) {
1462		sysctl_wmem_max = 131071;
1463		sysctl_rmem_max = 131071;
1464	}
1465}
1466
1467/*
1468 *	Simple resource managers for sockets.
1469 */
1470
1471
1472/*
1473 * Write buffer destructor automatically called from kfree_skb.
1474 */
1475void sock_wfree(struct sk_buff *skb)
1476{
1477	struct sock *sk = skb->sk;
1478	unsigned int len = skb->truesize;
1479
1480	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1481		/*
1482		 * Keep a reference on sk_wmem_alloc, this will be released
1483		 * after sk_write_space() call
1484		 */
1485		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1486		sk->sk_write_space(sk);
1487		len = 1;
1488	}
1489	/*
1490	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1491	 * could not do because of in-flight packets
1492	 */
1493	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1494		__sk_free(sk);
1495}
1496EXPORT_SYMBOL(sock_wfree);
1497
1498/*
1499 * Read buffer destructor automatically called from kfree_skb.
1500 */
1501void sock_rfree(struct sk_buff *skb)
1502{
1503	struct sock *sk = skb->sk;
1504	unsigned int len = skb->truesize;
1505
1506	atomic_sub(len, &sk->sk_rmem_alloc);
1507	sk_mem_uncharge(sk, len);
1508}
1509EXPORT_SYMBOL(sock_rfree);
1510
1511void sock_edemux(struct sk_buff *skb)
1512{
1513	sock_put(skb->sk);
1514}
1515EXPORT_SYMBOL(sock_edemux);
1516
1517int sock_i_uid(struct sock *sk)
1518{
1519	int uid;
1520
1521	read_lock_bh(&sk->sk_callback_lock);
1522	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1523	read_unlock_bh(&sk->sk_callback_lock);
1524	return uid;
1525}
1526EXPORT_SYMBOL(sock_i_uid);
1527
1528unsigned long sock_i_ino(struct sock *sk)
1529{
1530	unsigned long ino;
1531
1532	read_lock_bh(&sk->sk_callback_lock);
1533	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1534	read_unlock_bh(&sk->sk_callback_lock);
1535	return ino;
1536}
1537EXPORT_SYMBOL(sock_i_ino);
1538
1539/*
1540 * Allocate a skb from the socket's send buffer.
1541 */
1542struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1543			     gfp_t priority)
1544{
1545	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1546		struct sk_buff *skb = alloc_skb(size, priority);
1547		if (skb) {
1548			skb_set_owner_w(skb, sk);
1549			return skb;
1550		}
1551	}
1552	return NULL;
1553}
1554EXPORT_SYMBOL(sock_wmalloc);
1555
1556/*
1557 * Allocate a skb from the socket's receive buffer.
1558 */
1559struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1560			     gfp_t priority)
1561{
1562	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1563		struct sk_buff *skb = alloc_skb(size, priority);
1564		if (skb) {
1565			skb_set_owner_r(skb, sk);
1566			return skb;
1567		}
1568	}
1569	return NULL;
1570}
1571
1572/*
1573 * Allocate a memory block from the socket's option memory buffer.
1574 */
1575void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1576{
1577	if ((unsigned int)size <= sysctl_optmem_max &&
1578	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1579		void *mem;
1580		/* First do the add, to avoid the race if kmalloc
1581		 * might sleep.
1582		 */
1583		atomic_add(size, &sk->sk_omem_alloc);
1584		mem = kmalloc(size, priority);
1585		if (mem)
1586			return mem;
1587		atomic_sub(size, &sk->sk_omem_alloc);
1588	}
1589	return NULL;
1590}
1591EXPORT_SYMBOL(sock_kmalloc);
1592
1593/*
1594 * Free an option memory block.
1595 */
1596void sock_kfree_s(struct sock *sk, void *mem, int size)
1597{
1598	kfree(mem);
1599	atomic_sub(size, &sk->sk_omem_alloc);
1600}
1601EXPORT_SYMBOL(sock_kfree_s);
1602
1603/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1604   I think, these locks should be removed for datagram sockets.
1605 */
1606static long sock_wait_for_wmem(struct sock *sk, long timeo)
1607{
1608	DEFINE_WAIT(wait);
1609
1610	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1611	for (;;) {
1612		if (!timeo)
1613			break;
1614		if (signal_pending(current))
1615			break;
1616		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1617		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1618		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1619			break;
1620		if (sk->sk_shutdown & SEND_SHUTDOWN)
1621			break;
1622		if (sk->sk_err)
1623			break;
1624		timeo = schedule_timeout(timeo);
1625	}
1626	finish_wait(sk_sleep(sk), &wait);
1627	return timeo;
1628}
1629
1630
1631/*
1632 *	Generic send/receive buffer handlers
1633 */
1634
1635struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1636				     unsigned long data_len, int noblock,
1637				     int *errcode)
1638{
1639	struct sk_buff *skb;
1640	gfp_t gfp_mask;
1641	long timeo;
1642	int err;
1643	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1644
1645	err = -EMSGSIZE;
1646	if (npages > MAX_SKB_FRAGS)
1647		goto failure;
1648
1649	gfp_mask = sk->sk_allocation;
1650	if (gfp_mask & __GFP_WAIT)
1651		gfp_mask |= __GFP_REPEAT;
1652
1653	timeo = sock_sndtimeo(sk, noblock);
1654	while (1) {
1655		err = sock_error(sk);
1656		if (err != 0)
1657			goto failure;
1658
1659		err = -EPIPE;
1660		if (sk->sk_shutdown & SEND_SHUTDOWN)
1661			goto failure;
1662
1663		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1664			skb = alloc_skb(header_len, gfp_mask);
1665			if (skb) {
1666				int i;
1667
1668				/* No pages, we're done... */
1669				if (!data_len)
1670					break;
1671
1672				skb->truesize += data_len;
1673				skb_shinfo(skb)->nr_frags = npages;
1674				for (i = 0; i < npages; i++) {
1675					struct page *page;
1676
1677					page = alloc_pages(sk->sk_allocation, 0);
1678					if (!page) {
1679						err = -ENOBUFS;
1680						skb_shinfo(skb)->nr_frags = i;
1681						kfree_skb(skb);
1682						goto failure;
1683					}
1684
1685					__skb_fill_page_desc(skb, i,
1686							page, 0,
1687							(data_len >= PAGE_SIZE ?
1688							 PAGE_SIZE :
1689							 data_len));
1690					data_len -= PAGE_SIZE;
1691				}
1692
1693				/* Full success... */
1694				break;
1695			}
1696			err = -ENOBUFS;
1697			goto failure;
1698		}
1699		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1700		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1701		err = -EAGAIN;
1702		if (!timeo)
1703			goto failure;
1704		if (signal_pending(current))
1705			goto interrupted;
1706		timeo = sock_wait_for_wmem(sk, timeo);
1707	}
1708
1709	skb_set_owner_w(skb, sk);
1710	return skb;
1711
1712interrupted:
1713	err = sock_intr_errno(timeo);
1714failure:
1715	*errcode = err;
1716	return NULL;
1717}
1718EXPORT_SYMBOL(sock_alloc_send_pskb);
1719
1720struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1721				    int noblock, int *errcode)
1722{
1723	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1724}
1725EXPORT_SYMBOL(sock_alloc_send_skb);
1726
1727static void __lock_sock(struct sock *sk)
1728	__releases(&sk->sk_lock.slock)
1729	__acquires(&sk->sk_lock.slock)
1730{
1731	DEFINE_WAIT(wait);
1732
1733	for (;;) {
1734		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1735					TASK_UNINTERRUPTIBLE);
1736		spin_unlock_bh(&sk->sk_lock.slock);
1737		schedule();
1738		spin_lock_bh(&sk->sk_lock.slock);
1739		if (!sock_owned_by_user(sk))
1740			break;
1741	}
1742	finish_wait(&sk->sk_lock.wq, &wait);
1743}
1744
1745static void __release_sock(struct sock *sk)
1746	__releases(&sk->sk_lock.slock)
1747	__acquires(&sk->sk_lock.slock)
1748{
1749	struct sk_buff *skb = sk->sk_backlog.head;
1750
1751	do {
1752		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1753		bh_unlock_sock(sk);
1754
1755		do {
1756			struct sk_buff *next = skb->next;
1757
1758			prefetch(next);
1759			WARN_ON_ONCE(skb_dst_is_noref(skb));
1760			skb->next = NULL;
1761			sk_backlog_rcv(sk, skb);
1762
1763			/*
1764			 * We are in process context here with softirqs
1765			 * disabled, use cond_resched_softirq() to preempt.
1766			 * This is safe to do because we've taken the backlog
1767			 * queue private:
1768			 */
1769			cond_resched_softirq();
1770
1771			skb = next;
1772		} while (skb != NULL);
1773
1774		bh_lock_sock(sk);
1775	} while ((skb = sk->sk_backlog.head) != NULL);
1776
1777	/*
1778	 * Doing the zeroing here guarantee we can not loop forever
1779	 * while a wild producer attempts to flood us.
1780	 */
1781	sk->sk_backlog.len = 0;
1782}
1783
1784/**
1785 * sk_wait_data - wait for data to arrive at sk_receive_queue
1786 * @sk:    sock to wait on
1787 * @timeo: for how long
1788 *
1789 * Now socket state including sk->sk_err is changed only under lock,
1790 * hence we may omit checks after joining wait queue.
1791 * We check receive queue before schedule() only as optimization;
1792 * it is very likely that release_sock() added new data.
1793 */
1794int sk_wait_data(struct sock *sk, long *timeo)
1795{
1796	int rc;
1797	DEFINE_WAIT(wait);
1798
1799	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1800	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1801	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1802	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1803	finish_wait(sk_sleep(sk), &wait);
1804	return rc;
1805}
1806EXPORT_SYMBOL(sk_wait_data);
1807
1808/**
1809 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1810 *	@sk: socket
1811 *	@size: memory size to allocate
1812 *	@kind: allocation type
1813 *
1814 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1815 *	rmem allocation. This function assumes that protocols which have
1816 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1817 */
1818int __sk_mem_schedule(struct sock *sk, int size, int kind)
1819{
1820	struct proto *prot = sk->sk_prot;
1821	int amt = sk_mem_pages(size);
1822	long allocated;
1823	int parent_status = UNDER_LIMIT;
1824
1825	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1826
1827	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1828
1829	/* Under limit. */
1830	if (parent_status == UNDER_LIMIT &&
1831			allocated <= sk_prot_mem_limits(sk, 0)) {
1832		sk_leave_memory_pressure(sk);
1833		return 1;
1834	}
1835
1836	/* Under pressure. (we or our parents) */
1837	if ((parent_status > SOFT_LIMIT) ||
1838			allocated > sk_prot_mem_limits(sk, 1))
1839		sk_enter_memory_pressure(sk);
1840
1841	/* Over hard limit (we or our parents) */
1842	if ((parent_status == OVER_LIMIT) ||
1843			(allocated > sk_prot_mem_limits(sk, 2)))
1844		goto suppress_allocation;
1845
1846	/* guarantee minimum buffer size under pressure */
1847	if (kind == SK_MEM_RECV) {
1848		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1849			return 1;
1850
1851	} else { /* SK_MEM_SEND */
1852		if (sk->sk_type == SOCK_STREAM) {
1853			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1854				return 1;
1855		} else if (atomic_read(&sk->sk_wmem_alloc) <
1856			   prot->sysctl_wmem[0])
1857				return 1;
1858	}
1859
1860	if (sk_has_memory_pressure(sk)) {
1861		int alloc;
1862
1863		if (!sk_under_memory_pressure(sk))
1864			return 1;
1865		alloc = sk_sockets_allocated_read_positive(sk);
1866		if (sk_prot_mem_limits(sk, 2) > alloc *
1867		    sk_mem_pages(sk->sk_wmem_queued +
1868				 atomic_read(&sk->sk_rmem_alloc) +
1869				 sk->sk_forward_alloc))
1870			return 1;
1871	}
1872
1873suppress_allocation:
1874
1875	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1876		sk_stream_moderate_sndbuf(sk);
1877
1878		/* Fail only if socket is _under_ its sndbuf.
1879		 * In this case we cannot block, so that we have to fail.
1880		 */
1881		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1882			return 1;
1883	}
1884
1885	trace_sock_exceed_buf_limit(sk, prot, allocated);
1886
1887	/* Alas. Undo changes. */
1888	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1889
1890	sk_memory_allocated_sub(sk, amt);
1891
1892	return 0;
1893}
1894EXPORT_SYMBOL(__sk_mem_schedule);
1895
1896/**
1897 *	__sk_reclaim - reclaim memory_allocated
1898 *	@sk: socket
1899 */
1900void __sk_mem_reclaim(struct sock *sk)
1901{
1902	sk_memory_allocated_sub(sk,
1903				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
1904	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1905
1906	if (sk_under_memory_pressure(sk) &&
1907	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
1908		sk_leave_memory_pressure(sk);
1909}
1910EXPORT_SYMBOL(__sk_mem_reclaim);
1911
1912
1913/*
1914 * Set of default routines for initialising struct proto_ops when
1915 * the protocol does not support a particular function. In certain
1916 * cases where it makes no sense for a protocol to have a "do nothing"
1917 * function, some default processing is provided.
1918 */
1919
1920int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1921{
1922	return -EOPNOTSUPP;
1923}
1924EXPORT_SYMBOL(sock_no_bind);
1925
1926int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1927		    int len, int flags)
1928{
1929	return -EOPNOTSUPP;
1930}
1931EXPORT_SYMBOL(sock_no_connect);
1932
1933int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1934{
1935	return -EOPNOTSUPP;
1936}
1937EXPORT_SYMBOL(sock_no_socketpair);
1938
1939int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1940{
1941	return -EOPNOTSUPP;
1942}
1943EXPORT_SYMBOL(sock_no_accept);
1944
1945int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1946		    int *len, int peer)
1947{
1948	return -EOPNOTSUPP;
1949}
1950EXPORT_SYMBOL(sock_no_getname);
1951
1952unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1953{
1954	return 0;
1955}
1956EXPORT_SYMBOL(sock_no_poll);
1957
1958int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1959{
1960	return -EOPNOTSUPP;
1961}
1962EXPORT_SYMBOL(sock_no_ioctl);
1963
1964int sock_no_listen(struct socket *sock, int backlog)
1965{
1966	return -EOPNOTSUPP;
1967}
1968EXPORT_SYMBOL(sock_no_listen);
1969
1970int sock_no_shutdown(struct socket *sock, int how)
1971{
1972	return -EOPNOTSUPP;
1973}
1974EXPORT_SYMBOL(sock_no_shutdown);
1975
1976int sock_no_setsockopt(struct socket *sock, int level, int optname,
1977		    char __user *optval, unsigned int optlen)
1978{
1979	return -EOPNOTSUPP;
1980}
1981EXPORT_SYMBOL(sock_no_setsockopt);
1982
1983int sock_no_getsockopt(struct socket *sock, int level, int optname,
1984		    char __user *optval, int __user *optlen)
1985{
1986	return -EOPNOTSUPP;
1987}
1988EXPORT_SYMBOL(sock_no_getsockopt);
1989
1990int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1991		    size_t len)
1992{
1993	return -EOPNOTSUPP;
1994}
1995EXPORT_SYMBOL(sock_no_sendmsg);
1996
1997int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1998		    size_t len, int flags)
1999{
2000	return -EOPNOTSUPP;
2001}
2002EXPORT_SYMBOL(sock_no_recvmsg);
2003
2004int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2005{
2006	/* Mirror missing mmap method error code */
2007	return -ENODEV;
2008}
2009EXPORT_SYMBOL(sock_no_mmap);
2010
2011ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2012{
2013	ssize_t res;
2014	struct msghdr msg = {.msg_flags = flags};
2015	struct kvec iov;
2016	char *kaddr = kmap(page);
2017	iov.iov_base = kaddr + offset;
2018	iov.iov_len = size;
2019	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2020	kunmap(page);
2021	return res;
2022}
2023EXPORT_SYMBOL(sock_no_sendpage);
2024
2025/*
2026 *	Default Socket Callbacks
2027 */
2028
2029static void sock_def_wakeup(struct sock *sk)
2030{
2031	struct socket_wq *wq;
2032
2033	rcu_read_lock();
2034	wq = rcu_dereference(sk->sk_wq);
2035	if (wq_has_sleeper(wq))
2036		wake_up_interruptible_all(&wq->wait);
2037	rcu_read_unlock();
2038}
2039
2040static void sock_def_error_report(struct sock *sk)
2041{
2042	struct socket_wq *wq;
2043
2044	rcu_read_lock();
2045	wq = rcu_dereference(sk->sk_wq);
2046	if (wq_has_sleeper(wq))
2047		wake_up_interruptible_poll(&wq->wait, POLLERR);
2048	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2049	rcu_read_unlock();
2050}
2051
2052static void sock_def_readable(struct sock *sk, int len)
2053{
2054	struct socket_wq *wq;
2055
2056	rcu_read_lock();
2057	wq = rcu_dereference(sk->sk_wq);
2058	if (wq_has_sleeper(wq))
2059		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2060						POLLRDNORM | POLLRDBAND);
2061	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2062	rcu_read_unlock();
2063}
2064
2065static void sock_def_write_space(struct sock *sk)
2066{
2067	struct socket_wq *wq;
2068
2069	rcu_read_lock();
2070
2071	/* Do not wake up a writer until he can make "significant"
2072	 * progress.  --DaveM
2073	 */
2074	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2075		wq = rcu_dereference(sk->sk_wq);
2076		if (wq_has_sleeper(wq))
2077			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2078						POLLWRNORM | POLLWRBAND);
2079
2080		/* Should agree with poll, otherwise some programs break */
2081		if (sock_writeable(sk))
2082			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2083	}
2084
2085	rcu_read_unlock();
2086}
2087
2088static void sock_def_destruct(struct sock *sk)
2089{
2090	kfree(sk->sk_protinfo);
2091}
2092
2093void sk_send_sigurg(struct sock *sk)
2094{
2095	if (sk->sk_socket && sk->sk_socket->file)
2096		if (send_sigurg(&sk->sk_socket->file->f_owner))
2097			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2098}
2099EXPORT_SYMBOL(sk_send_sigurg);
2100
2101void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2102		    unsigned long expires)
2103{
2104	if (!mod_timer(timer, expires))
2105		sock_hold(sk);
2106}
2107EXPORT_SYMBOL(sk_reset_timer);
2108
2109void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2110{
2111	if (timer_pending(timer) && del_timer(timer))
2112		__sock_put(sk);
2113}
2114EXPORT_SYMBOL(sk_stop_timer);
2115
2116void sock_init_data(struct socket *sock, struct sock *sk)
2117{
2118	skb_queue_head_init(&sk->sk_receive_queue);
2119	skb_queue_head_init(&sk->sk_write_queue);
2120	skb_queue_head_init(&sk->sk_error_queue);
2121#ifdef CONFIG_NET_DMA
2122	skb_queue_head_init(&sk->sk_async_wait_queue);
2123#endif
2124
2125	sk->sk_send_head	=	NULL;
2126
2127	init_timer(&sk->sk_timer);
2128
2129	sk->sk_allocation	=	GFP_KERNEL;
2130	sk->sk_rcvbuf		=	sysctl_rmem_default;
2131	sk->sk_sndbuf		=	sysctl_wmem_default;
2132	sk->sk_state		=	TCP_CLOSE;
2133	sk_set_socket(sk, sock);
2134
2135	sock_set_flag(sk, SOCK_ZAPPED);
2136
2137	if (sock) {
2138		sk->sk_type	=	sock->type;
2139		sk->sk_wq	=	sock->wq;
2140		sock->sk	=	sk;
2141	} else
2142		sk->sk_wq	=	NULL;
2143
2144	spin_lock_init(&sk->sk_dst_lock);
2145	rwlock_init(&sk->sk_callback_lock);
2146	lockdep_set_class_and_name(&sk->sk_callback_lock,
2147			af_callback_keys + sk->sk_family,
2148			af_family_clock_key_strings[sk->sk_family]);
2149
2150	sk->sk_state_change	=	sock_def_wakeup;
2151	sk->sk_data_ready	=	sock_def_readable;
2152	sk->sk_write_space	=	sock_def_write_space;
2153	sk->sk_error_report	=	sock_def_error_report;
2154	sk->sk_destruct		=	sock_def_destruct;
2155
2156	sk->sk_sndmsg_page	=	NULL;
2157	sk->sk_sndmsg_off	=	0;
2158	sk->sk_peek_off		=	-1;
2159
2160	sk->sk_peer_pid 	=	NULL;
2161	sk->sk_peer_cred	=	NULL;
2162	sk->sk_write_pending	=	0;
2163	sk->sk_rcvlowat		=	1;
2164	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2165	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2166
2167	sk->sk_stamp = ktime_set(-1L, 0);
2168
2169	/*
2170	 * Before updating sk_refcnt, we must commit prior changes to memory
2171	 * (Documentation/RCU/rculist_nulls.txt for details)
2172	 */
2173	smp_wmb();
2174	atomic_set(&sk->sk_refcnt, 1);
2175	atomic_set(&sk->sk_drops, 0);
2176}
2177EXPORT_SYMBOL(sock_init_data);
2178
2179void lock_sock_nested(struct sock *sk, int subclass)
2180{
2181	might_sleep();
2182	spin_lock_bh(&sk->sk_lock.slock);
2183	if (sk->sk_lock.owned)
2184		__lock_sock(sk);
2185	sk->sk_lock.owned = 1;
2186	spin_unlock(&sk->sk_lock.slock);
2187	/*
2188	 * The sk_lock has mutex_lock() semantics here:
2189	 */
2190	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2191	local_bh_enable();
2192}
2193EXPORT_SYMBOL(lock_sock_nested);
2194
2195void release_sock(struct sock *sk)
2196{
2197	/*
2198	 * The sk_lock has mutex_unlock() semantics:
2199	 */
2200	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2201
2202	spin_lock_bh(&sk->sk_lock.slock);
2203	if (sk->sk_backlog.tail)
2204		__release_sock(sk);
2205
2206	if (sk->sk_prot->release_cb)
2207		sk->sk_prot->release_cb(sk);
2208
2209	sk->sk_lock.owned = 0;
2210	if (waitqueue_active(&sk->sk_lock.wq))
2211		wake_up(&sk->sk_lock.wq);
2212	spin_unlock_bh(&sk->sk_lock.slock);
2213}
2214EXPORT_SYMBOL(release_sock);
2215
2216/**
2217 * lock_sock_fast - fast version of lock_sock
2218 * @sk: socket
2219 *
2220 * This version should be used for very small section, where process wont block
2221 * return false if fast path is taken
2222 *   sk_lock.slock locked, owned = 0, BH disabled
2223 * return true if slow path is taken
2224 *   sk_lock.slock unlocked, owned = 1, BH enabled
2225 */
2226bool lock_sock_fast(struct sock *sk)
2227{
2228	might_sleep();
2229	spin_lock_bh(&sk->sk_lock.slock);
2230
2231	if (!sk->sk_lock.owned)
2232		/*
2233		 * Note : We must disable BH
2234		 */
2235		return false;
2236
2237	__lock_sock(sk);
2238	sk->sk_lock.owned = 1;
2239	spin_unlock(&sk->sk_lock.slock);
2240	/*
2241	 * The sk_lock has mutex_lock() semantics here:
2242	 */
2243	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2244	local_bh_enable();
2245	return true;
2246}
2247EXPORT_SYMBOL(lock_sock_fast);
2248
2249int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2250{
2251	struct timeval tv;
2252	if (!sock_flag(sk, SOCK_TIMESTAMP))
2253		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2254	tv = ktime_to_timeval(sk->sk_stamp);
2255	if (tv.tv_sec == -1)
2256		return -ENOENT;
2257	if (tv.tv_sec == 0) {
2258		sk->sk_stamp = ktime_get_real();
2259		tv = ktime_to_timeval(sk->sk_stamp);
2260	}
2261	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2262}
2263EXPORT_SYMBOL(sock_get_timestamp);
2264
2265int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2266{
2267	struct timespec ts;
2268	if (!sock_flag(sk, SOCK_TIMESTAMP))
2269		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2270	ts = ktime_to_timespec(sk->sk_stamp);
2271	if (ts.tv_sec == -1)
2272		return -ENOENT;
2273	if (ts.tv_sec == 0) {
2274		sk->sk_stamp = ktime_get_real();
2275		ts = ktime_to_timespec(sk->sk_stamp);
2276	}
2277	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2278}
2279EXPORT_SYMBOL(sock_get_timestampns);
2280
2281void sock_enable_timestamp(struct sock *sk, int flag)
2282{
2283	if (!sock_flag(sk, flag)) {
2284		unsigned long previous_flags = sk->sk_flags;
2285
2286		sock_set_flag(sk, flag);
2287		/*
2288		 * we just set one of the two flags which require net
2289		 * time stamping, but time stamping might have been on
2290		 * already because of the other one
2291		 */
2292		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2293			net_enable_timestamp();
2294	}
2295}
2296
2297/*
2298 *	Get a socket option on an socket.
2299 *
2300 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2301 *	asynchronous errors should be reported by getsockopt. We assume
2302 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2303 */
2304int sock_common_getsockopt(struct socket *sock, int level, int optname,
2305			   char __user *optval, int __user *optlen)
2306{
2307	struct sock *sk = sock->sk;
2308
2309	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2310}
2311EXPORT_SYMBOL(sock_common_getsockopt);
2312
2313#ifdef CONFIG_COMPAT
2314int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2315				  char __user *optval, int __user *optlen)
2316{
2317	struct sock *sk = sock->sk;
2318
2319	if (sk->sk_prot->compat_getsockopt != NULL)
2320		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2321						      optval, optlen);
2322	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2323}
2324EXPORT_SYMBOL(compat_sock_common_getsockopt);
2325#endif
2326
2327int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2328			struct msghdr *msg, size_t size, int flags)
2329{
2330	struct sock *sk = sock->sk;
2331	int addr_len = 0;
2332	int err;
2333
2334	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2335				   flags & ~MSG_DONTWAIT, &addr_len);
2336	if (err >= 0)
2337		msg->msg_namelen = addr_len;
2338	return err;
2339}
2340EXPORT_SYMBOL(sock_common_recvmsg);
2341
2342/*
2343 *	Set socket options on an inet socket.
2344 */
2345int sock_common_setsockopt(struct socket *sock, int level, int optname,
2346			   char __user *optval, unsigned int optlen)
2347{
2348	struct sock *sk = sock->sk;
2349
2350	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2351}
2352EXPORT_SYMBOL(sock_common_setsockopt);
2353
2354#ifdef CONFIG_COMPAT
2355int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2356				  char __user *optval, unsigned int optlen)
2357{
2358	struct sock *sk = sock->sk;
2359
2360	if (sk->sk_prot->compat_setsockopt != NULL)
2361		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2362						      optval, optlen);
2363	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2364}
2365EXPORT_SYMBOL(compat_sock_common_setsockopt);
2366#endif
2367
2368void sk_common_release(struct sock *sk)
2369{
2370	if (sk->sk_prot->destroy)
2371		sk->sk_prot->destroy(sk);
2372
2373	/*
2374	 * Observation: when sock_common_release is called, processes have
2375	 * no access to socket. But net still has.
2376	 * Step one, detach it from networking:
2377	 *
2378	 * A. Remove from hash tables.
2379	 */
2380
2381	sk->sk_prot->unhash(sk);
2382
2383	/*
2384	 * In this point socket cannot receive new packets, but it is possible
2385	 * that some packets are in flight because some CPU runs receiver and
2386	 * did hash table lookup before we unhashed socket. They will achieve
2387	 * receive queue and will be purged by socket destructor.
2388	 *
2389	 * Also we still have packets pending on receive queue and probably,
2390	 * our own packets waiting in device queues. sock_destroy will drain
2391	 * receive queue, but transmitted packets will delay socket destruction
2392	 * until the last reference will be released.
2393	 */
2394
2395	sock_orphan(sk);
2396
2397	xfrm_sk_free_policy(sk);
2398
2399	sk_refcnt_debug_release(sk);
2400	sock_put(sk);
2401}
2402EXPORT_SYMBOL(sk_common_release);
2403
2404#ifdef CONFIG_PROC_FS
2405#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2406struct prot_inuse {
2407	int val[PROTO_INUSE_NR];
2408};
2409
2410static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2411
2412#ifdef CONFIG_NET_NS
2413void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2414{
2415	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2416}
2417EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2418
2419int sock_prot_inuse_get(struct net *net, struct proto *prot)
2420{
2421	int cpu, idx = prot->inuse_idx;
2422	int res = 0;
2423
2424	for_each_possible_cpu(cpu)
2425		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2426
2427	return res >= 0 ? res : 0;
2428}
2429EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2430
2431static int __net_init sock_inuse_init_net(struct net *net)
2432{
2433	net->core.inuse = alloc_percpu(struct prot_inuse);
2434	return net->core.inuse ? 0 : -ENOMEM;
2435}
2436
2437static void __net_exit sock_inuse_exit_net(struct net *net)
2438{
2439	free_percpu(net->core.inuse);
2440}
2441
2442static struct pernet_operations net_inuse_ops = {
2443	.init = sock_inuse_init_net,
2444	.exit = sock_inuse_exit_net,
2445};
2446
2447static __init int net_inuse_init(void)
2448{
2449	if (register_pernet_subsys(&net_inuse_ops))
2450		panic("Cannot initialize net inuse counters");
2451
2452	return 0;
2453}
2454
2455core_initcall(net_inuse_init);
2456#else
2457static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2458
2459void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2460{
2461	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2462}
2463EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2464
2465int sock_prot_inuse_get(struct net *net, struct proto *prot)
2466{
2467	int cpu, idx = prot->inuse_idx;
2468	int res = 0;
2469
2470	for_each_possible_cpu(cpu)
2471		res += per_cpu(prot_inuse, cpu).val[idx];
2472
2473	return res >= 0 ? res : 0;
2474}
2475EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2476#endif
2477
2478static void assign_proto_idx(struct proto *prot)
2479{
2480	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2481
2482	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2483		pr_err("PROTO_INUSE_NR exhausted\n");
2484		return;
2485	}
2486
2487	set_bit(prot->inuse_idx, proto_inuse_idx);
2488}
2489
2490static void release_proto_idx(struct proto *prot)
2491{
2492	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2493		clear_bit(prot->inuse_idx, proto_inuse_idx);
2494}
2495#else
2496static inline void assign_proto_idx(struct proto *prot)
2497{
2498}
2499
2500static inline void release_proto_idx(struct proto *prot)
2501{
2502}
2503#endif
2504
2505int proto_register(struct proto *prot, int alloc_slab)
2506{
2507	if (alloc_slab) {
2508		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2509					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2510					NULL);
2511
2512		if (prot->slab == NULL) {
2513			pr_crit("%s: Can't create sock SLAB cache!\n",
2514				prot->name);
2515			goto out;
2516		}
2517
2518		if (prot->rsk_prot != NULL) {
2519			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2520			if (prot->rsk_prot->slab_name == NULL)
2521				goto out_free_sock_slab;
2522
2523			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2524								 prot->rsk_prot->obj_size, 0,
2525								 SLAB_HWCACHE_ALIGN, NULL);
2526
2527			if (prot->rsk_prot->slab == NULL) {
2528				pr_crit("%s: Can't create request sock SLAB cache!\n",
2529					prot->name);
2530				goto out_free_request_sock_slab_name;
2531			}
2532		}
2533
2534		if (prot->twsk_prot != NULL) {
2535			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2536
2537			if (prot->twsk_prot->twsk_slab_name == NULL)
2538				goto out_free_request_sock_slab;
2539
2540			prot->twsk_prot->twsk_slab =
2541				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2542						  prot->twsk_prot->twsk_obj_size,
2543						  0,
2544						  SLAB_HWCACHE_ALIGN |
2545							prot->slab_flags,
2546						  NULL);
2547			if (prot->twsk_prot->twsk_slab == NULL)
2548				goto out_free_timewait_sock_slab_name;
2549		}
2550	}
2551
2552	mutex_lock(&proto_list_mutex);
2553	list_add(&prot->node, &proto_list);
2554	assign_proto_idx(prot);
2555	mutex_unlock(&proto_list_mutex);
2556	return 0;
2557
2558out_free_timewait_sock_slab_name:
2559	kfree(prot->twsk_prot->twsk_slab_name);
2560out_free_request_sock_slab:
2561	if (prot->rsk_prot && prot->rsk_prot->slab) {
2562		kmem_cache_destroy(prot->rsk_prot->slab);
2563		prot->rsk_prot->slab = NULL;
2564	}
2565out_free_request_sock_slab_name:
2566	if (prot->rsk_prot)
2567		kfree(prot->rsk_prot->slab_name);
2568out_free_sock_slab:
2569	kmem_cache_destroy(prot->slab);
2570	prot->slab = NULL;
2571out:
2572	return -ENOBUFS;
2573}
2574EXPORT_SYMBOL(proto_register);
2575
2576void proto_unregister(struct proto *prot)
2577{
2578	mutex_lock(&proto_list_mutex);
2579	release_proto_idx(prot);
2580	list_del(&prot->node);
2581	mutex_unlock(&proto_list_mutex);
2582
2583	if (prot->slab != NULL) {
2584		kmem_cache_destroy(prot->slab);
2585		prot->slab = NULL;
2586	}
2587
2588	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2589		kmem_cache_destroy(prot->rsk_prot->slab);
2590		kfree(prot->rsk_prot->slab_name);
2591		prot->rsk_prot->slab = NULL;
2592	}
2593
2594	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2595		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2596		kfree(prot->twsk_prot->twsk_slab_name);
2597		prot->twsk_prot->twsk_slab = NULL;
2598	}
2599}
2600EXPORT_SYMBOL(proto_unregister);
2601
2602#ifdef CONFIG_PROC_FS
2603static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2604	__acquires(proto_list_mutex)
2605{
2606	mutex_lock(&proto_list_mutex);
2607	return seq_list_start_head(&proto_list, *pos);
2608}
2609
2610static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2611{
2612	return seq_list_next(v, &proto_list, pos);
2613}
2614
2615static void proto_seq_stop(struct seq_file *seq, void *v)
2616	__releases(proto_list_mutex)
2617{
2618	mutex_unlock(&proto_list_mutex);
2619}
2620
2621static char proto_method_implemented(const void *method)
2622{
2623	return method == NULL ? 'n' : 'y';
2624}
2625static long sock_prot_memory_allocated(struct proto *proto)
2626{
2627	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2628}
2629
2630static char *sock_prot_memory_pressure(struct proto *proto)
2631{
2632	return proto->memory_pressure != NULL ?
2633	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2634}
2635
2636static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2637{
2638
2639	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2640			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2641		   proto->name,
2642		   proto->obj_size,
2643		   sock_prot_inuse_get(seq_file_net(seq), proto),
2644		   sock_prot_memory_allocated(proto),
2645		   sock_prot_memory_pressure(proto),
2646		   proto->max_header,
2647		   proto->slab == NULL ? "no" : "yes",
2648		   module_name(proto->owner),
2649		   proto_method_implemented(proto->close),
2650		   proto_method_implemented(proto->connect),
2651		   proto_method_implemented(proto->disconnect),
2652		   proto_method_implemented(proto->accept),
2653		   proto_method_implemented(proto->ioctl),
2654		   proto_method_implemented(proto->init),
2655		   proto_method_implemented(proto->destroy),
2656		   proto_method_implemented(proto->shutdown),
2657		   proto_method_implemented(proto->setsockopt),
2658		   proto_method_implemented(proto->getsockopt),
2659		   proto_method_implemented(proto->sendmsg),
2660		   proto_method_implemented(proto->recvmsg),
2661		   proto_method_implemented(proto->sendpage),
2662		   proto_method_implemented(proto->bind),
2663		   proto_method_implemented(proto->backlog_rcv),
2664		   proto_method_implemented(proto->hash),
2665		   proto_method_implemented(proto->unhash),
2666		   proto_method_implemented(proto->get_port),
2667		   proto_method_implemented(proto->enter_memory_pressure));
2668}
2669
2670static int proto_seq_show(struct seq_file *seq, void *v)
2671{
2672	if (v == &proto_list)
2673		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2674			   "protocol",
2675			   "size",
2676			   "sockets",
2677			   "memory",
2678			   "press",
2679			   "maxhdr",
2680			   "slab",
2681			   "module",
2682			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2683	else
2684		proto_seq_printf(seq, list_entry(v, struct proto, node));
2685	return 0;
2686}
2687
2688static const struct seq_operations proto_seq_ops = {
2689	.start  = proto_seq_start,
2690	.next   = proto_seq_next,
2691	.stop   = proto_seq_stop,
2692	.show   = proto_seq_show,
2693};
2694
2695static int proto_seq_open(struct inode *inode, struct file *file)
2696{
2697	return seq_open_net(inode, file, &proto_seq_ops,
2698			    sizeof(struct seq_net_private));
2699}
2700
2701static const struct file_operations proto_seq_fops = {
2702	.owner		= THIS_MODULE,
2703	.open		= proto_seq_open,
2704	.read		= seq_read,
2705	.llseek		= seq_lseek,
2706	.release	= seq_release_net,
2707};
2708
2709static __net_init int proto_init_net(struct net *net)
2710{
2711	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2712		return -ENOMEM;
2713
2714	return 0;
2715}
2716
2717static __net_exit void proto_exit_net(struct net *net)
2718{
2719	proc_net_remove(net, "protocols");
2720}
2721
2722
2723static __net_initdata struct pernet_operations proto_net_ops = {
2724	.init = proto_init_net,
2725	.exit = proto_exit_net,
2726};
2727
2728static int __init proto_init(void)
2729{
2730	return register_pernet_subsys(&proto_net_ops);
2731}
2732
2733subsys_initcall(proto_init);
2734
2735#endif /* PROC_FS */
2736