sock.c revision d361fd599a991ff6c1d522a599c635b35d61ef30
1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  INET is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Generic socket support routines. Memory allocators, socket lock/release
7 *		handler for protocols to use and generic option handler.
8 *
9 *
10 * Authors:	Ross Biro
11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *		Florian La Roche, <flla@stud.uni-sb.de>
13 *		Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 *		Alan Cox	: 	Numerous verify_area() problems
17 *		Alan Cox	:	Connecting on a connecting socket
18 *					now returns an error for tcp.
19 *		Alan Cox	:	sock->protocol is set correctly.
20 *					and is not sometimes left as 0.
21 *		Alan Cox	:	connect handles icmp errors on a
22 *					connect properly. Unfortunately there
23 *					is a restart syscall nasty there. I
24 *					can't match BSD without hacking the C
25 *					library. Ideas urgently sought!
26 *		Alan Cox	:	Disallow bind() to addresses that are
27 *					not ours - especially broadcast ones!!
28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30 *					instead they leave that for the DESTROY timer.
31 *		Alan Cox	:	Clean up error flag in accept
32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33 *					was buggy. Put a remove_sock() in the handler
34 *					for memory when we hit 0. Also altered the timer
35 *					code. The ACK stuff can wait and needs major
36 *					TCP layer surgery.
37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38 *					and fixed timer/inet_bh race.
39 *		Alan Cox	:	Added zapped flag for TCP
40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47 *	Pauline Middelink	:	identd support
48 *		Alan Cox	:	Fixed connect() taking signals I think.
49 *		Alan Cox	:	SO_LINGER supported
50 *		Alan Cox	:	Error reporting fixes
51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52 *		Alan Cox	:	inet sockets don't set sk->type!
53 *		Alan Cox	:	Split socket option code
54 *		Alan Cox	:	Callbacks
55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56 *		Alex		:	Removed restriction on inet fioctl
57 *		Alan Cox	:	Splitting INET from NET core
58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60 *		Alan Cox	:	Split IP from generic code
61 *		Alan Cox	:	New kfree_skbmem()
62 *		Alan Cox	:	Make SO_DEBUG superuser only.
63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64 *					(compatibility fix)
65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66 *		Alan Cox	:	Allocator for a socket is settable.
67 *		Alan Cox	:	SO_ERROR includes soft errors.
68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69 *		Alan Cox	: 	Generic socket allocation to make hooks
70 *					easier (suggested by Craig Metz).
71 *		Michael Pall	:	SO_ERROR returns positive errno again
72 *              Steve Whitehouse:       Added default destructor to free
73 *                                      protocol private data.
74 *              Steve Whitehouse:       Added various other default routines
75 *                                      common to several socket families.
76 *              Chris Evans     :       Call suser() check last on F_SETOWN
77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79 *		Andi Kleen	:	Fix write_space callback
80 *		Chris Evans	:	Security fixes - signedness again
81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 *		This program is free software; you can redistribute it and/or
87 *		modify it under the terms of the GNU General Public License
88 *		as published by the Free Software Foundation; either version
89 *		2 of the License, or (at your option) any later version.
90 */
91
92#include <linux/capability.h>
93#include <linux/errno.h>
94#include <linux/types.h>
95#include <linux/socket.h>
96#include <linux/in.h>
97#include <linux/kernel.h>
98#include <linux/module.h>
99#include <linux/proc_fs.h>
100#include <linux/seq_file.h>
101#include <linux/sched.h>
102#include <linux/timer.h>
103#include <linux/string.h>
104#include <linux/sockios.h>
105#include <linux/net.h>
106#include <linux/mm.h>
107#include <linux/slab.h>
108#include <linux/interrupt.h>
109#include <linux/poll.h>
110#include <linux/tcp.h>
111#include <linux/init.h>
112#include <linux/highmem.h>
113#include <linux/user_namespace.h>
114
115#include <asm/uaccess.h>
116#include <asm/system.h>
117
118#include <linux/netdevice.h>
119#include <net/protocol.h>
120#include <linux/skbuff.h>
121#include <net/net_namespace.h>
122#include <net/request_sock.h>
123#include <net/sock.h>
124#include <linux/net_tstamp.h>
125#include <net/xfrm.h>
126#include <linux/ipsec.h>
127#include <net/cls_cgroup.h>
128
129#include <linux/filter.h>
130
131#ifdef CONFIG_INET
132#include <net/tcp.h>
133#endif
134
135/*
136 * Each address family might have different locking rules, so we have
137 * one slock key per address family:
138 */
139static struct lock_class_key af_family_keys[AF_MAX];
140static struct lock_class_key af_family_slock_keys[AF_MAX];
141
142/*
143 * Make lock validator output more readable. (we pre-construct these
144 * strings build-time, so that runtime initialization of socket
145 * locks is fast):
146 */
147static const char *const af_family_key_strings[AF_MAX+1] = {
148  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
149  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
150  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
151  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
152  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
153  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
154  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
155  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
156  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
157  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
158  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
159  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
160  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" ,
161  "sk_lock-AF_MAX"
162};
163static const char *const af_family_slock_key_strings[AF_MAX+1] = {
164  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
165  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
166  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
167  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
168  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
169  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
170  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
171  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
172  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
173  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
174  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
175  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
176  "slock-AF_IEEE802154", "slock-AF_CAIF" ,
177  "slock-AF_MAX"
178};
179static const char *const af_family_clock_key_strings[AF_MAX+1] = {
180  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
181  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
182  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
183  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
184  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
185  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
186  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
187  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
188  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
189  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
190  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
191  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
192  "clock-AF_IEEE802154", "clock-AF_CAIF" ,
193  "clock-AF_MAX"
194};
195
196/*
197 * sk_callback_lock locking rules are per-address-family,
198 * so split the lock classes by using a per-AF key:
199 */
200static struct lock_class_key af_callback_keys[AF_MAX];
201
202/* Take into consideration the size of the struct sk_buff overhead in the
203 * determination of these values, since that is non-constant across
204 * platforms.  This makes socket queueing behavior and performance
205 * not depend upon such differences.
206 */
207#define _SK_MEM_PACKETS		256
208#define _SK_MEM_OVERHEAD	(sizeof(struct sk_buff) + 256)
209#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
210#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
211
212/* Run time adjustable parameters. */
213__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
214__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
215__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
216__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
217
218/* Maximal space eaten by iovec or ancilliary data plus some space */
219int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
220EXPORT_SYMBOL(sysctl_optmem_max);
221
222#if defined(CONFIG_CGROUPS) && !defined(CONFIG_NET_CLS_CGROUP)
223int net_cls_subsys_id = -1;
224EXPORT_SYMBOL_GPL(net_cls_subsys_id);
225#endif
226
227static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
228{
229	struct timeval tv;
230
231	if (optlen < sizeof(tv))
232		return -EINVAL;
233	if (copy_from_user(&tv, optval, sizeof(tv)))
234		return -EFAULT;
235	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
236		return -EDOM;
237
238	if (tv.tv_sec < 0) {
239		static int warned __read_mostly;
240
241		*timeo_p = 0;
242		if (warned < 10 && net_ratelimit()) {
243			warned++;
244			printk(KERN_INFO "sock_set_timeout: `%s' (pid %d) "
245			       "tries to set negative timeout\n",
246				current->comm, task_pid_nr(current));
247		}
248		return 0;
249	}
250	*timeo_p = MAX_SCHEDULE_TIMEOUT;
251	if (tv.tv_sec == 0 && tv.tv_usec == 0)
252		return 0;
253	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
254		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
255	return 0;
256}
257
258static void sock_warn_obsolete_bsdism(const char *name)
259{
260	static int warned;
261	static char warncomm[TASK_COMM_LEN];
262	if (strcmp(warncomm, current->comm) && warned < 5) {
263		strcpy(warncomm,  current->comm);
264		printk(KERN_WARNING "process `%s' is using obsolete "
265		       "%s SO_BSDCOMPAT\n", warncomm, name);
266		warned++;
267	}
268}
269
270static void sock_disable_timestamp(struct sock *sk, int flag)
271{
272	if (sock_flag(sk, flag)) {
273		sock_reset_flag(sk, flag);
274		if (!sock_flag(sk, SOCK_TIMESTAMP) &&
275		    !sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) {
276			net_disable_timestamp();
277		}
278	}
279}
280
281
282int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
283{
284	int err;
285	int skb_len;
286	unsigned long flags;
287	struct sk_buff_head *list = &sk->sk_receive_queue;
288
289	/* Cast sk->rcvbuf to unsigned... It's pointless, but reduces
290	   number of warnings when compiling with -W --ANK
291	 */
292	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
293	    (unsigned)sk->sk_rcvbuf) {
294		atomic_inc(&sk->sk_drops);
295		return -ENOMEM;
296	}
297
298	err = sk_filter(sk, skb);
299	if (err)
300		return err;
301
302	if (!sk_rmem_schedule(sk, skb->truesize)) {
303		atomic_inc(&sk->sk_drops);
304		return -ENOBUFS;
305	}
306
307	skb->dev = NULL;
308	skb_set_owner_r(skb, sk);
309
310	/* Cache the SKB length before we tack it onto the receive
311	 * queue.  Once it is added it no longer belongs to us and
312	 * may be freed by other threads of control pulling packets
313	 * from the queue.
314	 */
315	skb_len = skb->len;
316
317	/* we escape from rcu protected region, make sure we dont leak
318	 * a norefcounted dst
319	 */
320	skb_dst_force(skb);
321
322	spin_lock_irqsave(&list->lock, flags);
323	skb->dropcount = atomic_read(&sk->sk_drops);
324	__skb_queue_tail(list, skb);
325	spin_unlock_irqrestore(&list->lock, flags);
326
327	if (!sock_flag(sk, SOCK_DEAD))
328		sk->sk_data_ready(sk, skb_len);
329	return 0;
330}
331EXPORT_SYMBOL(sock_queue_rcv_skb);
332
333int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
334{
335	int rc = NET_RX_SUCCESS;
336
337	if (sk_filter(sk, skb))
338		goto discard_and_relse;
339
340	skb->dev = NULL;
341
342	if (sk_rcvqueues_full(sk, skb)) {
343		atomic_inc(&sk->sk_drops);
344		goto discard_and_relse;
345	}
346	if (nested)
347		bh_lock_sock_nested(sk);
348	else
349		bh_lock_sock(sk);
350	if (!sock_owned_by_user(sk)) {
351		/*
352		 * trylock + unlock semantics:
353		 */
354		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
355
356		rc = sk_backlog_rcv(sk, skb);
357
358		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
359	} else if (sk_add_backlog(sk, skb)) {
360		bh_unlock_sock(sk);
361		atomic_inc(&sk->sk_drops);
362		goto discard_and_relse;
363	}
364
365	bh_unlock_sock(sk);
366out:
367	sock_put(sk);
368	return rc;
369discard_and_relse:
370	kfree_skb(skb);
371	goto out;
372}
373EXPORT_SYMBOL(sk_receive_skb);
374
375void sk_reset_txq(struct sock *sk)
376{
377	sk_tx_queue_clear(sk);
378}
379EXPORT_SYMBOL(sk_reset_txq);
380
381struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
382{
383	struct dst_entry *dst = __sk_dst_get(sk);
384
385	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
386		sk_tx_queue_clear(sk);
387		rcu_assign_pointer(sk->sk_dst_cache, NULL);
388		dst_release(dst);
389		return NULL;
390	}
391
392	return dst;
393}
394EXPORT_SYMBOL(__sk_dst_check);
395
396struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
397{
398	struct dst_entry *dst = sk_dst_get(sk);
399
400	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
401		sk_dst_reset(sk);
402		dst_release(dst);
403		return NULL;
404	}
405
406	return dst;
407}
408EXPORT_SYMBOL(sk_dst_check);
409
410static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
411{
412	int ret = -ENOPROTOOPT;
413#ifdef CONFIG_NETDEVICES
414	struct net *net = sock_net(sk);
415	char devname[IFNAMSIZ];
416	int index;
417
418	/* Sorry... */
419	ret = -EPERM;
420	if (!capable(CAP_NET_RAW))
421		goto out;
422
423	ret = -EINVAL;
424	if (optlen < 0)
425		goto out;
426
427	/* Bind this socket to a particular device like "eth0",
428	 * as specified in the passed interface name. If the
429	 * name is "" or the option length is zero the socket
430	 * is not bound.
431	 */
432	if (optlen > IFNAMSIZ - 1)
433		optlen = IFNAMSIZ - 1;
434	memset(devname, 0, sizeof(devname));
435
436	ret = -EFAULT;
437	if (copy_from_user(devname, optval, optlen))
438		goto out;
439
440	index = 0;
441	if (devname[0] != '\0') {
442		struct net_device *dev;
443
444		rcu_read_lock();
445		dev = dev_get_by_name_rcu(net, devname);
446		if (dev)
447			index = dev->ifindex;
448		rcu_read_unlock();
449		ret = -ENODEV;
450		if (!dev)
451			goto out;
452	}
453
454	lock_sock(sk);
455	sk->sk_bound_dev_if = index;
456	sk_dst_reset(sk);
457	release_sock(sk);
458
459	ret = 0;
460
461out:
462#endif
463
464	return ret;
465}
466
467static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
468{
469	if (valbool)
470		sock_set_flag(sk, bit);
471	else
472		sock_reset_flag(sk, bit);
473}
474
475/*
476 *	This is meant for all protocols to use and covers goings on
477 *	at the socket level. Everything here is generic.
478 */
479
480int sock_setsockopt(struct socket *sock, int level, int optname,
481		    char __user *optval, unsigned int optlen)
482{
483	struct sock *sk = sock->sk;
484	int val;
485	int valbool;
486	struct linger ling;
487	int ret = 0;
488
489	/*
490	 *	Options without arguments
491	 */
492
493	if (optname == SO_BINDTODEVICE)
494		return sock_bindtodevice(sk, optval, optlen);
495
496	if (optlen < sizeof(int))
497		return -EINVAL;
498
499	if (get_user(val, (int __user *)optval))
500		return -EFAULT;
501
502	valbool = val ? 1 : 0;
503
504	lock_sock(sk);
505
506	switch (optname) {
507	case SO_DEBUG:
508		if (val && !capable(CAP_NET_ADMIN))
509			ret = -EACCES;
510		else
511			sock_valbool_flag(sk, SOCK_DBG, valbool);
512		break;
513	case SO_REUSEADDR:
514		sk->sk_reuse = valbool;
515		break;
516	case SO_TYPE:
517	case SO_PROTOCOL:
518	case SO_DOMAIN:
519	case SO_ERROR:
520		ret = -ENOPROTOOPT;
521		break;
522	case SO_DONTROUTE:
523		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
524		break;
525	case SO_BROADCAST:
526		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
527		break;
528	case SO_SNDBUF:
529		/* Don't error on this BSD doesn't and if you think
530		   about it this is right. Otherwise apps have to
531		   play 'guess the biggest size' games. RCVBUF/SNDBUF
532		   are treated in BSD as hints */
533
534		if (val > sysctl_wmem_max)
535			val = sysctl_wmem_max;
536set_sndbuf:
537		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
538		if ((val * 2) < SOCK_MIN_SNDBUF)
539			sk->sk_sndbuf = SOCK_MIN_SNDBUF;
540		else
541			sk->sk_sndbuf = val * 2;
542
543		/*
544		 *	Wake up sending tasks if we
545		 *	upped the value.
546		 */
547		sk->sk_write_space(sk);
548		break;
549
550	case SO_SNDBUFFORCE:
551		if (!capable(CAP_NET_ADMIN)) {
552			ret = -EPERM;
553			break;
554		}
555		goto set_sndbuf;
556
557	case SO_RCVBUF:
558		/* Don't error on this BSD doesn't and if you think
559		   about it this is right. Otherwise apps have to
560		   play 'guess the biggest size' games. RCVBUF/SNDBUF
561		   are treated in BSD as hints */
562
563		if (val > sysctl_rmem_max)
564			val = sysctl_rmem_max;
565set_rcvbuf:
566		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
567		/*
568		 * We double it on the way in to account for
569		 * "struct sk_buff" etc. overhead.   Applications
570		 * assume that the SO_RCVBUF setting they make will
571		 * allow that much actual data to be received on that
572		 * socket.
573		 *
574		 * Applications are unaware that "struct sk_buff" and
575		 * other overheads allocate from the receive buffer
576		 * during socket buffer allocation.
577		 *
578		 * And after considering the possible alternatives,
579		 * returning the value we actually used in getsockopt
580		 * is the most desirable behavior.
581		 */
582		if ((val * 2) < SOCK_MIN_RCVBUF)
583			sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
584		else
585			sk->sk_rcvbuf = val * 2;
586		break;
587
588	case SO_RCVBUFFORCE:
589		if (!capable(CAP_NET_ADMIN)) {
590			ret = -EPERM;
591			break;
592		}
593		goto set_rcvbuf;
594
595	case SO_KEEPALIVE:
596#ifdef CONFIG_INET
597		if (sk->sk_protocol == IPPROTO_TCP)
598			tcp_set_keepalive(sk, valbool);
599#endif
600		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
601		break;
602
603	case SO_OOBINLINE:
604		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
605		break;
606
607	case SO_NO_CHECK:
608		sk->sk_no_check = valbool;
609		break;
610
611	case SO_PRIORITY:
612		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
613			sk->sk_priority = val;
614		else
615			ret = -EPERM;
616		break;
617
618	case SO_LINGER:
619		if (optlen < sizeof(ling)) {
620			ret = -EINVAL;	/* 1003.1g */
621			break;
622		}
623		if (copy_from_user(&ling, optval, sizeof(ling))) {
624			ret = -EFAULT;
625			break;
626		}
627		if (!ling.l_onoff)
628			sock_reset_flag(sk, SOCK_LINGER);
629		else {
630#if (BITS_PER_LONG == 32)
631			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
632				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
633			else
634#endif
635				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
636			sock_set_flag(sk, SOCK_LINGER);
637		}
638		break;
639
640	case SO_BSDCOMPAT:
641		sock_warn_obsolete_bsdism("setsockopt");
642		break;
643
644	case SO_PASSCRED:
645		if (valbool)
646			set_bit(SOCK_PASSCRED, &sock->flags);
647		else
648			clear_bit(SOCK_PASSCRED, &sock->flags);
649		break;
650
651	case SO_TIMESTAMP:
652	case SO_TIMESTAMPNS:
653		if (valbool)  {
654			if (optname == SO_TIMESTAMP)
655				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
656			else
657				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
658			sock_set_flag(sk, SOCK_RCVTSTAMP);
659			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
660		} else {
661			sock_reset_flag(sk, SOCK_RCVTSTAMP);
662			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
663		}
664		break;
665
666	case SO_TIMESTAMPING:
667		if (val & ~SOF_TIMESTAMPING_MASK) {
668			ret = -EINVAL;
669			break;
670		}
671		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
672				  val & SOF_TIMESTAMPING_TX_HARDWARE);
673		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
674				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
675		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
676				  val & SOF_TIMESTAMPING_RX_HARDWARE);
677		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
678			sock_enable_timestamp(sk,
679					      SOCK_TIMESTAMPING_RX_SOFTWARE);
680		else
681			sock_disable_timestamp(sk,
682					       SOCK_TIMESTAMPING_RX_SOFTWARE);
683		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
684				  val & SOF_TIMESTAMPING_SOFTWARE);
685		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
686				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
687		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
688				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
689		break;
690
691	case SO_RCVLOWAT:
692		if (val < 0)
693			val = INT_MAX;
694		sk->sk_rcvlowat = val ? : 1;
695		break;
696
697	case SO_RCVTIMEO:
698		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
699		break;
700
701	case SO_SNDTIMEO:
702		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
703		break;
704
705	case SO_ATTACH_FILTER:
706		ret = -EINVAL;
707		if (optlen == sizeof(struct sock_fprog)) {
708			struct sock_fprog fprog;
709
710			ret = -EFAULT;
711			if (copy_from_user(&fprog, optval, sizeof(fprog)))
712				break;
713
714			ret = sk_attach_filter(&fprog, sk);
715		}
716		break;
717
718	case SO_DETACH_FILTER:
719		ret = sk_detach_filter(sk);
720		break;
721
722	case SO_PASSSEC:
723		if (valbool)
724			set_bit(SOCK_PASSSEC, &sock->flags);
725		else
726			clear_bit(SOCK_PASSSEC, &sock->flags);
727		break;
728	case SO_MARK:
729		if (!capable(CAP_NET_ADMIN))
730			ret = -EPERM;
731		else
732			sk->sk_mark = val;
733		break;
734
735		/* We implement the SO_SNDLOWAT etc to
736		   not be settable (1003.1g 5.3) */
737	case SO_RXQ_OVFL:
738		if (valbool)
739			sock_set_flag(sk, SOCK_RXQ_OVFL);
740		else
741			sock_reset_flag(sk, SOCK_RXQ_OVFL);
742		break;
743	default:
744		ret = -ENOPROTOOPT;
745		break;
746	}
747	release_sock(sk);
748	return ret;
749}
750EXPORT_SYMBOL(sock_setsockopt);
751
752
753void cred_to_ucred(struct pid *pid, const struct cred *cred,
754		   struct ucred *ucred)
755{
756	ucred->pid = pid_vnr(pid);
757	ucred->uid = ucred->gid = -1;
758	if (cred) {
759		struct user_namespace *current_ns = current_user_ns();
760
761		ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
762		ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
763	}
764}
765EXPORT_SYMBOL_GPL(cred_to_ucred);
766
767int sock_getsockopt(struct socket *sock, int level, int optname,
768		    char __user *optval, int __user *optlen)
769{
770	struct sock *sk = sock->sk;
771
772	union {
773		int val;
774		struct linger ling;
775		struct timeval tm;
776	} v;
777
778	int lv = sizeof(int);
779	int len;
780
781	if (get_user(len, optlen))
782		return -EFAULT;
783	if (len < 0)
784		return -EINVAL;
785
786	memset(&v, 0, sizeof(v));
787
788	switch (optname) {
789	case SO_DEBUG:
790		v.val = sock_flag(sk, SOCK_DBG);
791		break;
792
793	case SO_DONTROUTE:
794		v.val = sock_flag(sk, SOCK_LOCALROUTE);
795		break;
796
797	case SO_BROADCAST:
798		v.val = !!sock_flag(sk, SOCK_BROADCAST);
799		break;
800
801	case SO_SNDBUF:
802		v.val = sk->sk_sndbuf;
803		break;
804
805	case SO_RCVBUF:
806		v.val = sk->sk_rcvbuf;
807		break;
808
809	case SO_REUSEADDR:
810		v.val = sk->sk_reuse;
811		break;
812
813	case SO_KEEPALIVE:
814		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
815		break;
816
817	case SO_TYPE:
818		v.val = sk->sk_type;
819		break;
820
821	case SO_PROTOCOL:
822		v.val = sk->sk_protocol;
823		break;
824
825	case SO_DOMAIN:
826		v.val = sk->sk_family;
827		break;
828
829	case SO_ERROR:
830		v.val = -sock_error(sk);
831		if (v.val == 0)
832			v.val = xchg(&sk->sk_err_soft, 0);
833		break;
834
835	case SO_OOBINLINE:
836		v.val = !!sock_flag(sk, SOCK_URGINLINE);
837		break;
838
839	case SO_NO_CHECK:
840		v.val = sk->sk_no_check;
841		break;
842
843	case SO_PRIORITY:
844		v.val = sk->sk_priority;
845		break;
846
847	case SO_LINGER:
848		lv		= sizeof(v.ling);
849		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
850		v.ling.l_linger	= sk->sk_lingertime / HZ;
851		break;
852
853	case SO_BSDCOMPAT:
854		sock_warn_obsolete_bsdism("getsockopt");
855		break;
856
857	case SO_TIMESTAMP:
858		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
859				!sock_flag(sk, SOCK_RCVTSTAMPNS);
860		break;
861
862	case SO_TIMESTAMPNS:
863		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
864		break;
865
866	case SO_TIMESTAMPING:
867		v.val = 0;
868		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
869			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
870		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
871			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
872		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
873			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
874		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
875			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
876		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
877			v.val |= SOF_TIMESTAMPING_SOFTWARE;
878		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
879			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
880		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
881			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
882		break;
883
884	case SO_RCVTIMEO:
885		lv = sizeof(struct timeval);
886		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
887			v.tm.tv_sec = 0;
888			v.tm.tv_usec = 0;
889		} else {
890			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
891			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
892		}
893		break;
894
895	case SO_SNDTIMEO:
896		lv = sizeof(struct timeval);
897		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
898			v.tm.tv_sec = 0;
899			v.tm.tv_usec = 0;
900		} else {
901			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
902			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
903		}
904		break;
905
906	case SO_RCVLOWAT:
907		v.val = sk->sk_rcvlowat;
908		break;
909
910	case SO_SNDLOWAT:
911		v.val = 1;
912		break;
913
914	case SO_PASSCRED:
915		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
916		break;
917
918	case SO_PEERCRED:
919	{
920		struct ucred peercred;
921		if (len > sizeof(peercred))
922			len = sizeof(peercred);
923		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
924		if (copy_to_user(optval, &peercred, len))
925			return -EFAULT;
926		goto lenout;
927	}
928
929	case SO_PEERNAME:
930	{
931		char address[128];
932
933		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
934			return -ENOTCONN;
935		if (lv < len)
936			return -EINVAL;
937		if (copy_to_user(optval, address, len))
938			return -EFAULT;
939		goto lenout;
940	}
941
942	/* Dubious BSD thing... Probably nobody even uses it, but
943	 * the UNIX standard wants it for whatever reason... -DaveM
944	 */
945	case SO_ACCEPTCONN:
946		v.val = sk->sk_state == TCP_LISTEN;
947		break;
948
949	case SO_PASSSEC:
950		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
951		break;
952
953	case SO_PEERSEC:
954		return security_socket_getpeersec_stream(sock, optval, optlen, len);
955
956	case SO_MARK:
957		v.val = sk->sk_mark;
958		break;
959
960	case SO_RXQ_OVFL:
961		v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
962		break;
963
964	default:
965		return -ENOPROTOOPT;
966	}
967
968	if (len > lv)
969		len = lv;
970	if (copy_to_user(optval, &v, len))
971		return -EFAULT;
972lenout:
973	if (put_user(len, optlen))
974		return -EFAULT;
975	return 0;
976}
977
978/*
979 * Initialize an sk_lock.
980 *
981 * (We also register the sk_lock with the lock validator.)
982 */
983static inline void sock_lock_init(struct sock *sk)
984{
985	sock_lock_init_class_and_name(sk,
986			af_family_slock_key_strings[sk->sk_family],
987			af_family_slock_keys + sk->sk_family,
988			af_family_key_strings[sk->sk_family],
989			af_family_keys + sk->sk_family);
990}
991
992/*
993 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
994 * even temporarly, because of RCU lookups. sk_node should also be left as is.
995 */
996static void sock_copy(struct sock *nsk, const struct sock *osk)
997{
998#ifdef CONFIG_SECURITY_NETWORK
999	void *sptr = nsk->sk_security;
1000#endif
1001	BUILD_BUG_ON(offsetof(struct sock, sk_copy_start) !=
1002		     sizeof(osk->sk_node) + sizeof(osk->sk_refcnt) +
1003		     sizeof(osk->sk_tx_queue_mapping));
1004	memcpy(&nsk->sk_copy_start, &osk->sk_copy_start,
1005	       osk->sk_prot->obj_size - offsetof(struct sock, sk_copy_start));
1006#ifdef CONFIG_SECURITY_NETWORK
1007	nsk->sk_security = sptr;
1008	security_sk_clone(osk, nsk);
1009#endif
1010}
1011
1012static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1013		int family)
1014{
1015	struct sock *sk;
1016	struct kmem_cache *slab;
1017
1018	slab = prot->slab;
1019	if (slab != NULL) {
1020		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1021		if (!sk)
1022			return sk;
1023		if (priority & __GFP_ZERO) {
1024			/*
1025			 * caches using SLAB_DESTROY_BY_RCU should let
1026			 * sk_node.next un-modified. Special care is taken
1027			 * when initializing object to zero.
1028			 */
1029			if (offsetof(struct sock, sk_node.next) != 0)
1030				memset(sk, 0, offsetof(struct sock, sk_node.next));
1031			memset(&sk->sk_node.pprev, 0,
1032			       prot->obj_size - offsetof(struct sock,
1033							 sk_node.pprev));
1034		}
1035	}
1036	else
1037		sk = kmalloc(prot->obj_size, priority);
1038
1039	if (sk != NULL) {
1040		kmemcheck_annotate_bitfield(sk, flags);
1041
1042		if (security_sk_alloc(sk, family, priority))
1043			goto out_free;
1044
1045		if (!try_module_get(prot->owner))
1046			goto out_free_sec;
1047		sk_tx_queue_clear(sk);
1048	}
1049
1050	return sk;
1051
1052out_free_sec:
1053	security_sk_free(sk);
1054out_free:
1055	if (slab != NULL)
1056		kmem_cache_free(slab, sk);
1057	else
1058		kfree(sk);
1059	return NULL;
1060}
1061
1062static void sk_prot_free(struct proto *prot, struct sock *sk)
1063{
1064	struct kmem_cache *slab;
1065	struct module *owner;
1066
1067	owner = prot->owner;
1068	slab = prot->slab;
1069
1070	security_sk_free(sk);
1071	if (slab != NULL)
1072		kmem_cache_free(slab, sk);
1073	else
1074		kfree(sk);
1075	module_put(owner);
1076}
1077
1078#ifdef CONFIG_CGROUPS
1079void sock_update_classid(struct sock *sk)
1080{
1081	u32 classid = task_cls_classid(current);
1082
1083	if (classid && classid != sk->sk_classid)
1084		sk->sk_classid = classid;
1085}
1086EXPORT_SYMBOL(sock_update_classid);
1087#endif
1088
1089/**
1090 *	sk_alloc - All socket objects are allocated here
1091 *	@net: the applicable net namespace
1092 *	@family: protocol family
1093 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1094 *	@prot: struct proto associated with this new sock instance
1095 */
1096struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1097		      struct proto *prot)
1098{
1099	struct sock *sk;
1100
1101	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1102	if (sk) {
1103		sk->sk_family = family;
1104		/*
1105		 * See comment in struct sock definition to understand
1106		 * why we need sk_prot_creator -acme
1107		 */
1108		sk->sk_prot = sk->sk_prot_creator = prot;
1109		sock_lock_init(sk);
1110		sock_net_set(sk, get_net(net));
1111		atomic_set(&sk->sk_wmem_alloc, 1);
1112
1113		sock_update_classid(sk);
1114	}
1115
1116	return sk;
1117}
1118EXPORT_SYMBOL(sk_alloc);
1119
1120static void __sk_free(struct sock *sk)
1121{
1122	struct sk_filter *filter;
1123
1124	if (sk->sk_destruct)
1125		sk->sk_destruct(sk);
1126
1127	filter = rcu_dereference_check(sk->sk_filter,
1128				       atomic_read(&sk->sk_wmem_alloc) == 0);
1129	if (filter) {
1130		sk_filter_uncharge(sk, filter);
1131		rcu_assign_pointer(sk->sk_filter, NULL);
1132	}
1133
1134	sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1135	sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1136
1137	if (atomic_read(&sk->sk_omem_alloc))
1138		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1139		       __func__, atomic_read(&sk->sk_omem_alloc));
1140
1141	if (sk->sk_peer_cred)
1142		put_cred(sk->sk_peer_cred);
1143	put_pid(sk->sk_peer_pid);
1144	put_net(sock_net(sk));
1145	sk_prot_free(sk->sk_prot_creator, sk);
1146}
1147
1148void sk_free(struct sock *sk)
1149{
1150	/*
1151	 * We substract one from sk_wmem_alloc and can know if
1152	 * some packets are still in some tx queue.
1153	 * If not null, sock_wfree() will call __sk_free(sk) later
1154	 */
1155	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1156		__sk_free(sk);
1157}
1158EXPORT_SYMBOL(sk_free);
1159
1160/*
1161 * Last sock_put should drop referrence to sk->sk_net. It has already
1162 * been dropped in sk_change_net. Taking referrence to stopping namespace
1163 * is not an option.
1164 * Take referrence to a socket to remove it from hash _alive_ and after that
1165 * destroy it in the context of init_net.
1166 */
1167void sk_release_kernel(struct sock *sk)
1168{
1169	if (sk == NULL || sk->sk_socket == NULL)
1170		return;
1171
1172	sock_hold(sk);
1173	sock_release(sk->sk_socket);
1174	release_net(sock_net(sk));
1175	sock_net_set(sk, get_net(&init_net));
1176	sock_put(sk);
1177}
1178EXPORT_SYMBOL(sk_release_kernel);
1179
1180struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1181{
1182	struct sock *newsk;
1183
1184	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1185	if (newsk != NULL) {
1186		struct sk_filter *filter;
1187
1188		sock_copy(newsk, sk);
1189
1190		/* SANITY */
1191		get_net(sock_net(newsk));
1192		sk_node_init(&newsk->sk_node);
1193		sock_lock_init(newsk);
1194		bh_lock_sock(newsk);
1195		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1196		newsk->sk_backlog.len = 0;
1197
1198		atomic_set(&newsk->sk_rmem_alloc, 0);
1199		/*
1200		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1201		 */
1202		atomic_set(&newsk->sk_wmem_alloc, 1);
1203		atomic_set(&newsk->sk_omem_alloc, 0);
1204		skb_queue_head_init(&newsk->sk_receive_queue);
1205		skb_queue_head_init(&newsk->sk_write_queue);
1206#ifdef CONFIG_NET_DMA
1207		skb_queue_head_init(&newsk->sk_async_wait_queue);
1208#endif
1209
1210		spin_lock_init(&newsk->sk_dst_lock);
1211		rwlock_init(&newsk->sk_callback_lock);
1212		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1213				af_callback_keys + newsk->sk_family,
1214				af_family_clock_key_strings[newsk->sk_family]);
1215
1216		newsk->sk_dst_cache	= NULL;
1217		newsk->sk_wmem_queued	= 0;
1218		newsk->sk_forward_alloc = 0;
1219		newsk->sk_send_head	= NULL;
1220		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1221
1222		sock_reset_flag(newsk, SOCK_DONE);
1223		skb_queue_head_init(&newsk->sk_error_queue);
1224
1225		filter = newsk->sk_filter;
1226		if (filter != NULL)
1227			sk_filter_charge(newsk, filter);
1228
1229		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1230			/* It is still raw copy of parent, so invalidate
1231			 * destructor and make plain sk_free() */
1232			newsk->sk_destruct = NULL;
1233			sk_free(newsk);
1234			newsk = NULL;
1235			goto out;
1236		}
1237
1238		newsk->sk_err	   = 0;
1239		newsk->sk_priority = 0;
1240		/*
1241		 * Before updating sk_refcnt, we must commit prior changes to memory
1242		 * (Documentation/RCU/rculist_nulls.txt for details)
1243		 */
1244		smp_wmb();
1245		atomic_set(&newsk->sk_refcnt, 2);
1246
1247		/*
1248		 * Increment the counter in the same struct proto as the master
1249		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1250		 * is the same as sk->sk_prot->socks, as this field was copied
1251		 * with memcpy).
1252		 *
1253		 * This _changes_ the previous behaviour, where
1254		 * tcp_create_openreq_child always was incrementing the
1255		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1256		 * to be taken into account in all callers. -acme
1257		 */
1258		sk_refcnt_debug_inc(newsk);
1259		sk_set_socket(newsk, NULL);
1260		newsk->sk_wq = NULL;
1261
1262		if (newsk->sk_prot->sockets_allocated)
1263			percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1264
1265		if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1266		    sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1267			net_enable_timestamp();
1268	}
1269out:
1270	return newsk;
1271}
1272EXPORT_SYMBOL_GPL(sk_clone);
1273
1274void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1275{
1276	__sk_dst_set(sk, dst);
1277	sk->sk_route_caps = dst->dev->features;
1278	if (sk->sk_route_caps & NETIF_F_GSO)
1279		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1280	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1281	if (sk_can_gso(sk)) {
1282		if (dst->header_len) {
1283			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1284		} else {
1285			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1286			sk->sk_gso_max_size = dst->dev->gso_max_size;
1287		}
1288	}
1289}
1290EXPORT_SYMBOL_GPL(sk_setup_caps);
1291
1292void __init sk_init(void)
1293{
1294	if (totalram_pages <= 4096) {
1295		sysctl_wmem_max = 32767;
1296		sysctl_rmem_max = 32767;
1297		sysctl_wmem_default = 32767;
1298		sysctl_rmem_default = 32767;
1299	} else if (totalram_pages >= 131072) {
1300		sysctl_wmem_max = 131071;
1301		sysctl_rmem_max = 131071;
1302	}
1303}
1304
1305/*
1306 *	Simple resource managers for sockets.
1307 */
1308
1309
1310/*
1311 * Write buffer destructor automatically called from kfree_skb.
1312 */
1313void sock_wfree(struct sk_buff *skb)
1314{
1315	struct sock *sk = skb->sk;
1316	unsigned int len = skb->truesize;
1317
1318	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1319		/*
1320		 * Keep a reference on sk_wmem_alloc, this will be released
1321		 * after sk_write_space() call
1322		 */
1323		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1324		sk->sk_write_space(sk);
1325		len = 1;
1326	}
1327	/*
1328	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1329	 * could not do because of in-flight packets
1330	 */
1331	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1332		__sk_free(sk);
1333}
1334EXPORT_SYMBOL(sock_wfree);
1335
1336/*
1337 * Read buffer destructor automatically called from kfree_skb.
1338 */
1339void sock_rfree(struct sk_buff *skb)
1340{
1341	struct sock *sk = skb->sk;
1342	unsigned int len = skb->truesize;
1343
1344	atomic_sub(len, &sk->sk_rmem_alloc);
1345	sk_mem_uncharge(sk, len);
1346}
1347EXPORT_SYMBOL(sock_rfree);
1348
1349
1350int sock_i_uid(struct sock *sk)
1351{
1352	int uid;
1353
1354	read_lock(&sk->sk_callback_lock);
1355	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1356	read_unlock(&sk->sk_callback_lock);
1357	return uid;
1358}
1359EXPORT_SYMBOL(sock_i_uid);
1360
1361unsigned long sock_i_ino(struct sock *sk)
1362{
1363	unsigned long ino;
1364
1365	read_lock(&sk->sk_callback_lock);
1366	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1367	read_unlock(&sk->sk_callback_lock);
1368	return ino;
1369}
1370EXPORT_SYMBOL(sock_i_ino);
1371
1372/*
1373 * Allocate a skb from the socket's send buffer.
1374 */
1375struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1376			     gfp_t priority)
1377{
1378	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1379		struct sk_buff *skb = alloc_skb(size, priority);
1380		if (skb) {
1381			skb_set_owner_w(skb, sk);
1382			return skb;
1383		}
1384	}
1385	return NULL;
1386}
1387EXPORT_SYMBOL(sock_wmalloc);
1388
1389/*
1390 * Allocate a skb from the socket's receive buffer.
1391 */
1392struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1393			     gfp_t priority)
1394{
1395	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1396		struct sk_buff *skb = alloc_skb(size, priority);
1397		if (skb) {
1398			skb_set_owner_r(skb, sk);
1399			return skb;
1400		}
1401	}
1402	return NULL;
1403}
1404
1405/*
1406 * Allocate a memory block from the socket's option memory buffer.
1407 */
1408void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1409{
1410	if ((unsigned)size <= sysctl_optmem_max &&
1411	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1412		void *mem;
1413		/* First do the add, to avoid the race if kmalloc
1414		 * might sleep.
1415		 */
1416		atomic_add(size, &sk->sk_omem_alloc);
1417		mem = kmalloc(size, priority);
1418		if (mem)
1419			return mem;
1420		atomic_sub(size, &sk->sk_omem_alloc);
1421	}
1422	return NULL;
1423}
1424EXPORT_SYMBOL(sock_kmalloc);
1425
1426/*
1427 * Free an option memory block.
1428 */
1429void sock_kfree_s(struct sock *sk, void *mem, int size)
1430{
1431	kfree(mem);
1432	atomic_sub(size, &sk->sk_omem_alloc);
1433}
1434EXPORT_SYMBOL(sock_kfree_s);
1435
1436/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1437   I think, these locks should be removed for datagram sockets.
1438 */
1439static long sock_wait_for_wmem(struct sock *sk, long timeo)
1440{
1441	DEFINE_WAIT(wait);
1442
1443	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1444	for (;;) {
1445		if (!timeo)
1446			break;
1447		if (signal_pending(current))
1448			break;
1449		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1450		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1451		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1452			break;
1453		if (sk->sk_shutdown & SEND_SHUTDOWN)
1454			break;
1455		if (sk->sk_err)
1456			break;
1457		timeo = schedule_timeout(timeo);
1458	}
1459	finish_wait(sk_sleep(sk), &wait);
1460	return timeo;
1461}
1462
1463
1464/*
1465 *	Generic send/receive buffer handlers
1466 */
1467
1468struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1469				     unsigned long data_len, int noblock,
1470				     int *errcode)
1471{
1472	struct sk_buff *skb;
1473	gfp_t gfp_mask;
1474	long timeo;
1475	int err;
1476
1477	gfp_mask = sk->sk_allocation;
1478	if (gfp_mask & __GFP_WAIT)
1479		gfp_mask |= __GFP_REPEAT;
1480
1481	timeo = sock_sndtimeo(sk, noblock);
1482	while (1) {
1483		err = sock_error(sk);
1484		if (err != 0)
1485			goto failure;
1486
1487		err = -EPIPE;
1488		if (sk->sk_shutdown & SEND_SHUTDOWN)
1489			goto failure;
1490
1491		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1492			skb = alloc_skb(header_len, gfp_mask);
1493			if (skb) {
1494				int npages;
1495				int i;
1496
1497				/* No pages, we're done... */
1498				if (!data_len)
1499					break;
1500
1501				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1502				skb->truesize += data_len;
1503				skb_shinfo(skb)->nr_frags = npages;
1504				for (i = 0; i < npages; i++) {
1505					struct page *page;
1506					skb_frag_t *frag;
1507
1508					page = alloc_pages(sk->sk_allocation, 0);
1509					if (!page) {
1510						err = -ENOBUFS;
1511						skb_shinfo(skb)->nr_frags = i;
1512						kfree_skb(skb);
1513						goto failure;
1514					}
1515
1516					frag = &skb_shinfo(skb)->frags[i];
1517					frag->page = page;
1518					frag->page_offset = 0;
1519					frag->size = (data_len >= PAGE_SIZE ?
1520						      PAGE_SIZE :
1521						      data_len);
1522					data_len -= PAGE_SIZE;
1523				}
1524
1525				/* Full success... */
1526				break;
1527			}
1528			err = -ENOBUFS;
1529			goto failure;
1530		}
1531		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1532		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1533		err = -EAGAIN;
1534		if (!timeo)
1535			goto failure;
1536		if (signal_pending(current))
1537			goto interrupted;
1538		timeo = sock_wait_for_wmem(sk, timeo);
1539	}
1540
1541	skb_set_owner_w(skb, sk);
1542	return skb;
1543
1544interrupted:
1545	err = sock_intr_errno(timeo);
1546failure:
1547	*errcode = err;
1548	return NULL;
1549}
1550EXPORT_SYMBOL(sock_alloc_send_pskb);
1551
1552struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1553				    int noblock, int *errcode)
1554{
1555	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1556}
1557EXPORT_SYMBOL(sock_alloc_send_skb);
1558
1559static void __lock_sock(struct sock *sk)
1560{
1561	DEFINE_WAIT(wait);
1562
1563	for (;;) {
1564		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1565					TASK_UNINTERRUPTIBLE);
1566		spin_unlock_bh(&sk->sk_lock.slock);
1567		schedule();
1568		spin_lock_bh(&sk->sk_lock.slock);
1569		if (!sock_owned_by_user(sk))
1570			break;
1571	}
1572	finish_wait(&sk->sk_lock.wq, &wait);
1573}
1574
1575static void __release_sock(struct sock *sk)
1576{
1577	struct sk_buff *skb = sk->sk_backlog.head;
1578
1579	do {
1580		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1581		bh_unlock_sock(sk);
1582
1583		do {
1584			struct sk_buff *next = skb->next;
1585
1586			WARN_ON_ONCE(skb_dst_is_noref(skb));
1587			skb->next = NULL;
1588			sk_backlog_rcv(sk, skb);
1589
1590			/*
1591			 * We are in process context here with softirqs
1592			 * disabled, use cond_resched_softirq() to preempt.
1593			 * This is safe to do because we've taken the backlog
1594			 * queue private:
1595			 */
1596			cond_resched_softirq();
1597
1598			skb = next;
1599		} while (skb != NULL);
1600
1601		bh_lock_sock(sk);
1602	} while ((skb = sk->sk_backlog.head) != NULL);
1603
1604	/*
1605	 * Doing the zeroing here guarantee we can not loop forever
1606	 * while a wild producer attempts to flood us.
1607	 */
1608	sk->sk_backlog.len = 0;
1609}
1610
1611/**
1612 * sk_wait_data - wait for data to arrive at sk_receive_queue
1613 * @sk:    sock to wait on
1614 * @timeo: for how long
1615 *
1616 * Now socket state including sk->sk_err is changed only under lock,
1617 * hence we may omit checks after joining wait queue.
1618 * We check receive queue before schedule() only as optimization;
1619 * it is very likely that release_sock() added new data.
1620 */
1621int sk_wait_data(struct sock *sk, long *timeo)
1622{
1623	int rc;
1624	DEFINE_WAIT(wait);
1625
1626	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1627	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1628	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1629	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1630	finish_wait(sk_sleep(sk), &wait);
1631	return rc;
1632}
1633EXPORT_SYMBOL(sk_wait_data);
1634
1635/**
1636 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1637 *	@sk: socket
1638 *	@size: memory size to allocate
1639 *	@kind: allocation type
1640 *
1641 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1642 *	rmem allocation. This function assumes that protocols which have
1643 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1644 */
1645int __sk_mem_schedule(struct sock *sk, int size, int kind)
1646{
1647	struct proto *prot = sk->sk_prot;
1648	int amt = sk_mem_pages(size);
1649	int allocated;
1650
1651	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1652	allocated = atomic_add_return(amt, prot->memory_allocated);
1653
1654	/* Under limit. */
1655	if (allocated <= prot->sysctl_mem[0]) {
1656		if (prot->memory_pressure && *prot->memory_pressure)
1657			*prot->memory_pressure = 0;
1658		return 1;
1659	}
1660
1661	/* Under pressure. */
1662	if (allocated > prot->sysctl_mem[1])
1663		if (prot->enter_memory_pressure)
1664			prot->enter_memory_pressure(sk);
1665
1666	/* Over hard limit. */
1667	if (allocated > prot->sysctl_mem[2])
1668		goto suppress_allocation;
1669
1670	/* guarantee minimum buffer size under pressure */
1671	if (kind == SK_MEM_RECV) {
1672		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1673			return 1;
1674	} else { /* SK_MEM_SEND */
1675		if (sk->sk_type == SOCK_STREAM) {
1676			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1677				return 1;
1678		} else if (atomic_read(&sk->sk_wmem_alloc) <
1679			   prot->sysctl_wmem[0])
1680				return 1;
1681	}
1682
1683	if (prot->memory_pressure) {
1684		int alloc;
1685
1686		if (!*prot->memory_pressure)
1687			return 1;
1688		alloc = percpu_counter_read_positive(prot->sockets_allocated);
1689		if (prot->sysctl_mem[2] > alloc *
1690		    sk_mem_pages(sk->sk_wmem_queued +
1691				 atomic_read(&sk->sk_rmem_alloc) +
1692				 sk->sk_forward_alloc))
1693			return 1;
1694	}
1695
1696suppress_allocation:
1697
1698	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1699		sk_stream_moderate_sndbuf(sk);
1700
1701		/* Fail only if socket is _under_ its sndbuf.
1702		 * In this case we cannot block, so that we have to fail.
1703		 */
1704		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1705			return 1;
1706	}
1707
1708	/* Alas. Undo changes. */
1709	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1710	atomic_sub(amt, prot->memory_allocated);
1711	return 0;
1712}
1713EXPORT_SYMBOL(__sk_mem_schedule);
1714
1715/**
1716 *	__sk_reclaim - reclaim memory_allocated
1717 *	@sk: socket
1718 */
1719void __sk_mem_reclaim(struct sock *sk)
1720{
1721	struct proto *prot = sk->sk_prot;
1722
1723	atomic_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1724		   prot->memory_allocated);
1725	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1726
1727	if (prot->memory_pressure && *prot->memory_pressure &&
1728	    (atomic_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1729		*prot->memory_pressure = 0;
1730}
1731EXPORT_SYMBOL(__sk_mem_reclaim);
1732
1733
1734/*
1735 * Set of default routines for initialising struct proto_ops when
1736 * the protocol does not support a particular function. In certain
1737 * cases where it makes no sense for a protocol to have a "do nothing"
1738 * function, some default processing is provided.
1739 */
1740
1741int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1742{
1743	return -EOPNOTSUPP;
1744}
1745EXPORT_SYMBOL(sock_no_bind);
1746
1747int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1748		    int len, int flags)
1749{
1750	return -EOPNOTSUPP;
1751}
1752EXPORT_SYMBOL(sock_no_connect);
1753
1754int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1755{
1756	return -EOPNOTSUPP;
1757}
1758EXPORT_SYMBOL(sock_no_socketpair);
1759
1760int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1761{
1762	return -EOPNOTSUPP;
1763}
1764EXPORT_SYMBOL(sock_no_accept);
1765
1766int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1767		    int *len, int peer)
1768{
1769	return -EOPNOTSUPP;
1770}
1771EXPORT_SYMBOL(sock_no_getname);
1772
1773unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1774{
1775	return 0;
1776}
1777EXPORT_SYMBOL(sock_no_poll);
1778
1779int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1780{
1781	return -EOPNOTSUPP;
1782}
1783EXPORT_SYMBOL(sock_no_ioctl);
1784
1785int sock_no_listen(struct socket *sock, int backlog)
1786{
1787	return -EOPNOTSUPP;
1788}
1789EXPORT_SYMBOL(sock_no_listen);
1790
1791int sock_no_shutdown(struct socket *sock, int how)
1792{
1793	return -EOPNOTSUPP;
1794}
1795EXPORT_SYMBOL(sock_no_shutdown);
1796
1797int sock_no_setsockopt(struct socket *sock, int level, int optname,
1798		    char __user *optval, unsigned int optlen)
1799{
1800	return -EOPNOTSUPP;
1801}
1802EXPORT_SYMBOL(sock_no_setsockopt);
1803
1804int sock_no_getsockopt(struct socket *sock, int level, int optname,
1805		    char __user *optval, int __user *optlen)
1806{
1807	return -EOPNOTSUPP;
1808}
1809EXPORT_SYMBOL(sock_no_getsockopt);
1810
1811int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1812		    size_t len)
1813{
1814	return -EOPNOTSUPP;
1815}
1816EXPORT_SYMBOL(sock_no_sendmsg);
1817
1818int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1819		    size_t len, int flags)
1820{
1821	return -EOPNOTSUPP;
1822}
1823EXPORT_SYMBOL(sock_no_recvmsg);
1824
1825int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1826{
1827	/* Mirror missing mmap method error code */
1828	return -ENODEV;
1829}
1830EXPORT_SYMBOL(sock_no_mmap);
1831
1832ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1833{
1834	ssize_t res;
1835	struct msghdr msg = {.msg_flags = flags};
1836	struct kvec iov;
1837	char *kaddr = kmap(page);
1838	iov.iov_base = kaddr + offset;
1839	iov.iov_len = size;
1840	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1841	kunmap(page);
1842	return res;
1843}
1844EXPORT_SYMBOL(sock_no_sendpage);
1845
1846/*
1847 *	Default Socket Callbacks
1848 */
1849
1850static void sock_def_wakeup(struct sock *sk)
1851{
1852	struct socket_wq *wq;
1853
1854	rcu_read_lock();
1855	wq = rcu_dereference(sk->sk_wq);
1856	if (wq_has_sleeper(wq))
1857		wake_up_interruptible_all(&wq->wait);
1858	rcu_read_unlock();
1859}
1860
1861static void sock_def_error_report(struct sock *sk)
1862{
1863	struct socket_wq *wq;
1864
1865	rcu_read_lock();
1866	wq = rcu_dereference(sk->sk_wq);
1867	if (wq_has_sleeper(wq))
1868		wake_up_interruptible_poll(&wq->wait, POLLERR);
1869	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1870	rcu_read_unlock();
1871}
1872
1873static void sock_def_readable(struct sock *sk, int len)
1874{
1875	struct socket_wq *wq;
1876
1877	rcu_read_lock();
1878	wq = rcu_dereference(sk->sk_wq);
1879	if (wq_has_sleeper(wq))
1880		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
1881						POLLRDNORM | POLLRDBAND);
1882	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1883	rcu_read_unlock();
1884}
1885
1886static void sock_def_write_space(struct sock *sk)
1887{
1888	struct socket_wq *wq;
1889
1890	rcu_read_lock();
1891
1892	/* Do not wake up a writer until he can make "significant"
1893	 * progress.  --DaveM
1894	 */
1895	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1896		wq = rcu_dereference(sk->sk_wq);
1897		if (wq_has_sleeper(wq))
1898			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1899						POLLWRNORM | POLLWRBAND);
1900
1901		/* Should agree with poll, otherwise some programs break */
1902		if (sock_writeable(sk))
1903			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1904	}
1905
1906	rcu_read_unlock();
1907}
1908
1909static void sock_def_destruct(struct sock *sk)
1910{
1911	kfree(sk->sk_protinfo);
1912}
1913
1914void sk_send_sigurg(struct sock *sk)
1915{
1916	if (sk->sk_socket && sk->sk_socket->file)
1917		if (send_sigurg(&sk->sk_socket->file->f_owner))
1918			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1919}
1920EXPORT_SYMBOL(sk_send_sigurg);
1921
1922void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1923		    unsigned long expires)
1924{
1925	if (!mod_timer(timer, expires))
1926		sock_hold(sk);
1927}
1928EXPORT_SYMBOL(sk_reset_timer);
1929
1930void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1931{
1932	if (timer_pending(timer) && del_timer(timer))
1933		__sock_put(sk);
1934}
1935EXPORT_SYMBOL(sk_stop_timer);
1936
1937void sock_init_data(struct socket *sock, struct sock *sk)
1938{
1939	skb_queue_head_init(&sk->sk_receive_queue);
1940	skb_queue_head_init(&sk->sk_write_queue);
1941	skb_queue_head_init(&sk->sk_error_queue);
1942#ifdef CONFIG_NET_DMA
1943	skb_queue_head_init(&sk->sk_async_wait_queue);
1944#endif
1945
1946	sk->sk_send_head	=	NULL;
1947
1948	init_timer(&sk->sk_timer);
1949
1950	sk->sk_allocation	=	GFP_KERNEL;
1951	sk->sk_rcvbuf		=	sysctl_rmem_default;
1952	sk->sk_sndbuf		=	sysctl_wmem_default;
1953	sk->sk_state		=	TCP_CLOSE;
1954	sk_set_socket(sk, sock);
1955
1956	sock_set_flag(sk, SOCK_ZAPPED);
1957
1958	if (sock) {
1959		sk->sk_type	=	sock->type;
1960		sk->sk_wq	=	sock->wq;
1961		sock->sk	=	sk;
1962	} else
1963		sk->sk_wq	=	NULL;
1964
1965	spin_lock_init(&sk->sk_dst_lock);
1966	rwlock_init(&sk->sk_callback_lock);
1967	lockdep_set_class_and_name(&sk->sk_callback_lock,
1968			af_callback_keys + sk->sk_family,
1969			af_family_clock_key_strings[sk->sk_family]);
1970
1971	sk->sk_state_change	=	sock_def_wakeup;
1972	sk->sk_data_ready	=	sock_def_readable;
1973	sk->sk_write_space	=	sock_def_write_space;
1974	sk->sk_error_report	=	sock_def_error_report;
1975	sk->sk_destruct		=	sock_def_destruct;
1976
1977	sk->sk_sndmsg_page	=	NULL;
1978	sk->sk_sndmsg_off	=	0;
1979
1980	sk->sk_peer_pid 	=	NULL;
1981	sk->sk_peer_cred	=	NULL;
1982	sk->sk_write_pending	=	0;
1983	sk->sk_rcvlowat		=	1;
1984	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
1985	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
1986
1987	sk->sk_stamp = ktime_set(-1L, 0);
1988
1989	/*
1990	 * Before updating sk_refcnt, we must commit prior changes to memory
1991	 * (Documentation/RCU/rculist_nulls.txt for details)
1992	 */
1993	smp_wmb();
1994	atomic_set(&sk->sk_refcnt, 1);
1995	atomic_set(&sk->sk_drops, 0);
1996}
1997EXPORT_SYMBOL(sock_init_data);
1998
1999void lock_sock_nested(struct sock *sk, int subclass)
2000{
2001	might_sleep();
2002	spin_lock_bh(&sk->sk_lock.slock);
2003	if (sk->sk_lock.owned)
2004		__lock_sock(sk);
2005	sk->sk_lock.owned = 1;
2006	spin_unlock(&sk->sk_lock.slock);
2007	/*
2008	 * The sk_lock has mutex_lock() semantics here:
2009	 */
2010	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2011	local_bh_enable();
2012}
2013EXPORT_SYMBOL(lock_sock_nested);
2014
2015void release_sock(struct sock *sk)
2016{
2017	/*
2018	 * The sk_lock has mutex_unlock() semantics:
2019	 */
2020	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2021
2022	spin_lock_bh(&sk->sk_lock.slock);
2023	if (sk->sk_backlog.tail)
2024		__release_sock(sk);
2025	sk->sk_lock.owned = 0;
2026	if (waitqueue_active(&sk->sk_lock.wq))
2027		wake_up(&sk->sk_lock.wq);
2028	spin_unlock_bh(&sk->sk_lock.slock);
2029}
2030EXPORT_SYMBOL(release_sock);
2031
2032/**
2033 * lock_sock_fast - fast version of lock_sock
2034 * @sk: socket
2035 *
2036 * This version should be used for very small section, where process wont block
2037 * return false if fast path is taken
2038 *   sk_lock.slock locked, owned = 0, BH disabled
2039 * return true if slow path is taken
2040 *   sk_lock.slock unlocked, owned = 1, BH enabled
2041 */
2042bool lock_sock_fast(struct sock *sk)
2043{
2044	might_sleep();
2045	spin_lock_bh(&sk->sk_lock.slock);
2046
2047	if (!sk->sk_lock.owned)
2048		/*
2049		 * Note : We must disable BH
2050		 */
2051		return false;
2052
2053	__lock_sock(sk);
2054	sk->sk_lock.owned = 1;
2055	spin_unlock(&sk->sk_lock.slock);
2056	/*
2057	 * The sk_lock has mutex_lock() semantics here:
2058	 */
2059	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2060	local_bh_enable();
2061	return true;
2062}
2063EXPORT_SYMBOL(lock_sock_fast);
2064
2065int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2066{
2067	struct timeval tv;
2068	if (!sock_flag(sk, SOCK_TIMESTAMP))
2069		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2070	tv = ktime_to_timeval(sk->sk_stamp);
2071	if (tv.tv_sec == -1)
2072		return -ENOENT;
2073	if (tv.tv_sec == 0) {
2074		sk->sk_stamp = ktime_get_real();
2075		tv = ktime_to_timeval(sk->sk_stamp);
2076	}
2077	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2078}
2079EXPORT_SYMBOL(sock_get_timestamp);
2080
2081int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2082{
2083	struct timespec ts;
2084	if (!sock_flag(sk, SOCK_TIMESTAMP))
2085		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2086	ts = ktime_to_timespec(sk->sk_stamp);
2087	if (ts.tv_sec == -1)
2088		return -ENOENT;
2089	if (ts.tv_sec == 0) {
2090		sk->sk_stamp = ktime_get_real();
2091		ts = ktime_to_timespec(sk->sk_stamp);
2092	}
2093	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2094}
2095EXPORT_SYMBOL(sock_get_timestampns);
2096
2097void sock_enable_timestamp(struct sock *sk, int flag)
2098{
2099	if (!sock_flag(sk, flag)) {
2100		sock_set_flag(sk, flag);
2101		/*
2102		 * we just set one of the two flags which require net
2103		 * time stamping, but time stamping might have been on
2104		 * already because of the other one
2105		 */
2106		if (!sock_flag(sk,
2107				flag == SOCK_TIMESTAMP ?
2108				SOCK_TIMESTAMPING_RX_SOFTWARE :
2109				SOCK_TIMESTAMP))
2110			net_enable_timestamp();
2111	}
2112}
2113
2114/*
2115 *	Get a socket option on an socket.
2116 *
2117 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2118 *	asynchronous errors should be reported by getsockopt. We assume
2119 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2120 */
2121int sock_common_getsockopt(struct socket *sock, int level, int optname,
2122			   char __user *optval, int __user *optlen)
2123{
2124	struct sock *sk = sock->sk;
2125
2126	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2127}
2128EXPORT_SYMBOL(sock_common_getsockopt);
2129
2130#ifdef CONFIG_COMPAT
2131int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2132				  char __user *optval, int __user *optlen)
2133{
2134	struct sock *sk = sock->sk;
2135
2136	if (sk->sk_prot->compat_getsockopt != NULL)
2137		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2138						      optval, optlen);
2139	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2140}
2141EXPORT_SYMBOL(compat_sock_common_getsockopt);
2142#endif
2143
2144int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2145			struct msghdr *msg, size_t size, int flags)
2146{
2147	struct sock *sk = sock->sk;
2148	int addr_len = 0;
2149	int err;
2150
2151	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2152				   flags & ~MSG_DONTWAIT, &addr_len);
2153	if (err >= 0)
2154		msg->msg_namelen = addr_len;
2155	return err;
2156}
2157EXPORT_SYMBOL(sock_common_recvmsg);
2158
2159/*
2160 *	Set socket options on an inet socket.
2161 */
2162int sock_common_setsockopt(struct socket *sock, int level, int optname,
2163			   char __user *optval, unsigned int optlen)
2164{
2165	struct sock *sk = sock->sk;
2166
2167	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2168}
2169EXPORT_SYMBOL(sock_common_setsockopt);
2170
2171#ifdef CONFIG_COMPAT
2172int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2173				  char __user *optval, unsigned int optlen)
2174{
2175	struct sock *sk = sock->sk;
2176
2177	if (sk->sk_prot->compat_setsockopt != NULL)
2178		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2179						      optval, optlen);
2180	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2181}
2182EXPORT_SYMBOL(compat_sock_common_setsockopt);
2183#endif
2184
2185void sk_common_release(struct sock *sk)
2186{
2187	if (sk->sk_prot->destroy)
2188		sk->sk_prot->destroy(sk);
2189
2190	/*
2191	 * Observation: when sock_common_release is called, processes have
2192	 * no access to socket. But net still has.
2193	 * Step one, detach it from networking:
2194	 *
2195	 * A. Remove from hash tables.
2196	 */
2197
2198	sk->sk_prot->unhash(sk);
2199
2200	/*
2201	 * In this point socket cannot receive new packets, but it is possible
2202	 * that some packets are in flight because some CPU runs receiver and
2203	 * did hash table lookup before we unhashed socket. They will achieve
2204	 * receive queue and will be purged by socket destructor.
2205	 *
2206	 * Also we still have packets pending on receive queue and probably,
2207	 * our own packets waiting in device queues. sock_destroy will drain
2208	 * receive queue, but transmitted packets will delay socket destruction
2209	 * until the last reference will be released.
2210	 */
2211
2212	sock_orphan(sk);
2213
2214	xfrm_sk_free_policy(sk);
2215
2216	sk_refcnt_debug_release(sk);
2217	sock_put(sk);
2218}
2219EXPORT_SYMBOL(sk_common_release);
2220
2221static DEFINE_RWLOCK(proto_list_lock);
2222static LIST_HEAD(proto_list);
2223
2224#ifdef CONFIG_PROC_FS
2225#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2226struct prot_inuse {
2227	int val[PROTO_INUSE_NR];
2228};
2229
2230static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2231
2232#ifdef CONFIG_NET_NS
2233void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2234{
2235	int cpu = smp_processor_id();
2236	per_cpu_ptr(net->core.inuse, cpu)->val[prot->inuse_idx] += val;
2237}
2238EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2239
2240int sock_prot_inuse_get(struct net *net, struct proto *prot)
2241{
2242	int cpu, idx = prot->inuse_idx;
2243	int res = 0;
2244
2245	for_each_possible_cpu(cpu)
2246		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2247
2248	return res >= 0 ? res : 0;
2249}
2250EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2251
2252static int __net_init sock_inuse_init_net(struct net *net)
2253{
2254	net->core.inuse = alloc_percpu(struct prot_inuse);
2255	return net->core.inuse ? 0 : -ENOMEM;
2256}
2257
2258static void __net_exit sock_inuse_exit_net(struct net *net)
2259{
2260	free_percpu(net->core.inuse);
2261}
2262
2263static struct pernet_operations net_inuse_ops = {
2264	.init = sock_inuse_init_net,
2265	.exit = sock_inuse_exit_net,
2266};
2267
2268static __init int net_inuse_init(void)
2269{
2270	if (register_pernet_subsys(&net_inuse_ops))
2271		panic("Cannot initialize net inuse counters");
2272
2273	return 0;
2274}
2275
2276core_initcall(net_inuse_init);
2277#else
2278static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2279
2280void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2281{
2282	__get_cpu_var(prot_inuse).val[prot->inuse_idx] += val;
2283}
2284EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2285
2286int sock_prot_inuse_get(struct net *net, struct proto *prot)
2287{
2288	int cpu, idx = prot->inuse_idx;
2289	int res = 0;
2290
2291	for_each_possible_cpu(cpu)
2292		res += per_cpu(prot_inuse, cpu).val[idx];
2293
2294	return res >= 0 ? res : 0;
2295}
2296EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2297#endif
2298
2299static void assign_proto_idx(struct proto *prot)
2300{
2301	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2302
2303	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2304		printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2305		return;
2306	}
2307
2308	set_bit(prot->inuse_idx, proto_inuse_idx);
2309}
2310
2311static void release_proto_idx(struct proto *prot)
2312{
2313	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2314		clear_bit(prot->inuse_idx, proto_inuse_idx);
2315}
2316#else
2317static inline void assign_proto_idx(struct proto *prot)
2318{
2319}
2320
2321static inline void release_proto_idx(struct proto *prot)
2322{
2323}
2324#endif
2325
2326int proto_register(struct proto *prot, int alloc_slab)
2327{
2328	if (alloc_slab) {
2329		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2330					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2331					NULL);
2332
2333		if (prot->slab == NULL) {
2334			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2335			       prot->name);
2336			goto out;
2337		}
2338
2339		if (prot->rsk_prot != NULL) {
2340			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2341			if (prot->rsk_prot->slab_name == NULL)
2342				goto out_free_sock_slab;
2343
2344			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2345								 prot->rsk_prot->obj_size, 0,
2346								 SLAB_HWCACHE_ALIGN, NULL);
2347
2348			if (prot->rsk_prot->slab == NULL) {
2349				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2350				       prot->name);
2351				goto out_free_request_sock_slab_name;
2352			}
2353		}
2354
2355		if (prot->twsk_prot != NULL) {
2356			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2357
2358			if (prot->twsk_prot->twsk_slab_name == NULL)
2359				goto out_free_request_sock_slab;
2360
2361			prot->twsk_prot->twsk_slab =
2362				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2363						  prot->twsk_prot->twsk_obj_size,
2364						  0,
2365						  SLAB_HWCACHE_ALIGN |
2366							prot->slab_flags,
2367						  NULL);
2368			if (prot->twsk_prot->twsk_slab == NULL)
2369				goto out_free_timewait_sock_slab_name;
2370		}
2371	}
2372
2373	write_lock(&proto_list_lock);
2374	list_add(&prot->node, &proto_list);
2375	assign_proto_idx(prot);
2376	write_unlock(&proto_list_lock);
2377	return 0;
2378
2379out_free_timewait_sock_slab_name:
2380	kfree(prot->twsk_prot->twsk_slab_name);
2381out_free_request_sock_slab:
2382	if (prot->rsk_prot && prot->rsk_prot->slab) {
2383		kmem_cache_destroy(prot->rsk_prot->slab);
2384		prot->rsk_prot->slab = NULL;
2385	}
2386out_free_request_sock_slab_name:
2387	if (prot->rsk_prot)
2388		kfree(prot->rsk_prot->slab_name);
2389out_free_sock_slab:
2390	kmem_cache_destroy(prot->slab);
2391	prot->slab = NULL;
2392out:
2393	return -ENOBUFS;
2394}
2395EXPORT_SYMBOL(proto_register);
2396
2397void proto_unregister(struct proto *prot)
2398{
2399	write_lock(&proto_list_lock);
2400	release_proto_idx(prot);
2401	list_del(&prot->node);
2402	write_unlock(&proto_list_lock);
2403
2404	if (prot->slab != NULL) {
2405		kmem_cache_destroy(prot->slab);
2406		prot->slab = NULL;
2407	}
2408
2409	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2410		kmem_cache_destroy(prot->rsk_prot->slab);
2411		kfree(prot->rsk_prot->slab_name);
2412		prot->rsk_prot->slab = NULL;
2413	}
2414
2415	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2416		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2417		kfree(prot->twsk_prot->twsk_slab_name);
2418		prot->twsk_prot->twsk_slab = NULL;
2419	}
2420}
2421EXPORT_SYMBOL(proto_unregister);
2422
2423#ifdef CONFIG_PROC_FS
2424static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2425	__acquires(proto_list_lock)
2426{
2427	read_lock(&proto_list_lock);
2428	return seq_list_start_head(&proto_list, *pos);
2429}
2430
2431static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2432{
2433	return seq_list_next(v, &proto_list, pos);
2434}
2435
2436static void proto_seq_stop(struct seq_file *seq, void *v)
2437	__releases(proto_list_lock)
2438{
2439	read_unlock(&proto_list_lock);
2440}
2441
2442static char proto_method_implemented(const void *method)
2443{
2444	return method == NULL ? 'n' : 'y';
2445}
2446
2447static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2448{
2449	seq_printf(seq, "%-9s %4u %6d  %6d   %-3s %6u   %-3s  %-10s "
2450			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2451		   proto->name,
2452		   proto->obj_size,
2453		   sock_prot_inuse_get(seq_file_net(seq), proto),
2454		   proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
2455		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2456		   proto->max_header,
2457		   proto->slab == NULL ? "no" : "yes",
2458		   module_name(proto->owner),
2459		   proto_method_implemented(proto->close),
2460		   proto_method_implemented(proto->connect),
2461		   proto_method_implemented(proto->disconnect),
2462		   proto_method_implemented(proto->accept),
2463		   proto_method_implemented(proto->ioctl),
2464		   proto_method_implemented(proto->init),
2465		   proto_method_implemented(proto->destroy),
2466		   proto_method_implemented(proto->shutdown),
2467		   proto_method_implemented(proto->setsockopt),
2468		   proto_method_implemented(proto->getsockopt),
2469		   proto_method_implemented(proto->sendmsg),
2470		   proto_method_implemented(proto->recvmsg),
2471		   proto_method_implemented(proto->sendpage),
2472		   proto_method_implemented(proto->bind),
2473		   proto_method_implemented(proto->backlog_rcv),
2474		   proto_method_implemented(proto->hash),
2475		   proto_method_implemented(proto->unhash),
2476		   proto_method_implemented(proto->get_port),
2477		   proto_method_implemented(proto->enter_memory_pressure));
2478}
2479
2480static int proto_seq_show(struct seq_file *seq, void *v)
2481{
2482	if (v == &proto_list)
2483		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2484			   "protocol",
2485			   "size",
2486			   "sockets",
2487			   "memory",
2488			   "press",
2489			   "maxhdr",
2490			   "slab",
2491			   "module",
2492			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2493	else
2494		proto_seq_printf(seq, list_entry(v, struct proto, node));
2495	return 0;
2496}
2497
2498static const struct seq_operations proto_seq_ops = {
2499	.start  = proto_seq_start,
2500	.next   = proto_seq_next,
2501	.stop   = proto_seq_stop,
2502	.show   = proto_seq_show,
2503};
2504
2505static int proto_seq_open(struct inode *inode, struct file *file)
2506{
2507	return seq_open_net(inode, file, &proto_seq_ops,
2508			    sizeof(struct seq_net_private));
2509}
2510
2511static const struct file_operations proto_seq_fops = {
2512	.owner		= THIS_MODULE,
2513	.open		= proto_seq_open,
2514	.read		= seq_read,
2515	.llseek		= seq_lseek,
2516	.release	= seq_release_net,
2517};
2518
2519static __net_init int proto_init_net(struct net *net)
2520{
2521	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2522		return -ENOMEM;
2523
2524	return 0;
2525}
2526
2527static __net_exit void proto_exit_net(struct net *net)
2528{
2529	proc_net_remove(net, "protocols");
2530}
2531
2532
2533static __net_initdata struct pernet_operations proto_net_ops = {
2534	.init = proto_init_net,
2535	.exit = proto_exit_net,
2536};
2537
2538static int __init proto_init(void)
2539{
2540	return register_pernet_subsys(&proto_net_ops);
2541}
2542
2543subsys_initcall(proto_init);
2544
2545#endif /* PROC_FS */
2546