]> bbs.cooldavid.org Git - net-next-2.6.git/blob - net/core/sock.c
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[net-next-2.6.git] / net / core / sock.c
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  */
139 static struct lock_class_key af_family_keys[AF_MAX];
140 static 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  */
147 static 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 };
163 static 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 };
179 static 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  */
200 static 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 */
219 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
220 EXPORT_SYMBOL(sysctl_optmem_max);
221
222 #if defined(CONFIG_CGROUPS) && !defined(CONFIG_NET_CLS_CGROUP)
223 int net_cls_subsys_id = -1;
224 EXPORT_SYMBOL_GPL(net_cls_subsys_id);
225 #endif
226
227 static 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
258 static 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
270 static 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
282 int 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 }
331 EXPORT_SYMBOL(sock_queue_rcv_skb);
332
333 int 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);
366 out:
367         sock_put(sk);
368         return rc;
369 discard_and_relse:
370         kfree_skb(skb);
371         goto out;
372 }
373 EXPORT_SYMBOL(sk_receive_skb);
374
375 void sk_reset_txq(struct sock *sk)
376 {
377         sk_tx_queue_clear(sk);
378 }
379 EXPORT_SYMBOL(sk_reset_txq);
380
381 struct 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 }
394 EXPORT_SYMBOL(__sk_dst_check);
395
396 struct 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 }
408 EXPORT_SYMBOL(sk_dst_check);
409
410 static 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
461 out:
462 #endif
463
464         return ret;
465 }
466
467 static 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
480 int 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;
536 set_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;
565 set_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 }
750 EXPORT_SYMBOL(sock_setsockopt);
751
752
753 void cred_to_ucred(struct pid *pid, const struct cred *cred,
754                    struct ucred *ucred)
755 {
756         ucred->pid = pid_vnr(pid);
757         ucred->uid = ucred->gid = -1;
758         if (cred) {
759                 struct user_namespace *current_ns = current_user_ns();
760
761                 ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
762                 ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
763         }
764 }
765 EXPORT_SYMBOL_GPL(cred_to_ucred);
766
767 int sock_getsockopt(struct socket *sock, int level, int optname,
768                     char __user *optval, int __user *optlen)
769 {
770         struct sock *sk = sock->sk;
771
772         union {
773                 int val;
774                 struct linger ling;
775                 struct timeval tm;
776         } v;
777
778         int lv = sizeof(int);
779         int len;
780
781         if (get_user(len, optlen))
782                 return -EFAULT;
783         if (len < 0)
784                 return -EINVAL;
785
786         memset(&v, 0, sizeof(v));
787
788         switch (optname) {
789         case SO_DEBUG:
790                 v.val = sock_flag(sk, SOCK_DBG);
791                 break;
792
793         case SO_DONTROUTE:
794                 v.val = sock_flag(sk, SOCK_LOCALROUTE);
795                 break;
796
797         case SO_BROADCAST:
798                 v.val = !!sock_flag(sk, SOCK_BROADCAST);
799                 break;
800
801         case SO_SNDBUF:
802                 v.val = sk->sk_sndbuf;
803                 break;
804
805         case SO_RCVBUF:
806                 v.val = sk->sk_rcvbuf;
807                 break;
808
809         case SO_REUSEADDR:
810                 v.val = sk->sk_reuse;
811                 break;
812
813         case SO_KEEPALIVE:
814                 v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
815                 break;
816
817         case SO_TYPE:
818                 v.val = sk->sk_type;
819                 break;
820
821         case SO_PROTOCOL:
822                 v.val = sk->sk_protocol;
823                 break;
824
825         case SO_DOMAIN:
826                 v.val = sk->sk_family;
827                 break;
828
829         case SO_ERROR:
830                 v.val = -sock_error(sk);
831                 if (v.val == 0)
832                         v.val = xchg(&sk->sk_err_soft, 0);
833                 break;
834
835         case SO_OOBINLINE:
836                 v.val = !!sock_flag(sk, SOCK_URGINLINE);
837                 break;
838
839         case SO_NO_CHECK:
840                 v.val = sk->sk_no_check;
841                 break;
842
843         case SO_PRIORITY:
844                 v.val = sk->sk_priority;
845                 break;
846
847         case SO_LINGER:
848                 lv              = sizeof(v.ling);
849                 v.ling.l_onoff  = !!sock_flag(sk, SOCK_LINGER);
850                 v.ling.l_linger = sk->sk_lingertime / HZ;
851                 break;
852
853         case SO_BSDCOMPAT:
854                 sock_warn_obsolete_bsdism("getsockopt");
855                 break;
856
857         case SO_TIMESTAMP:
858                 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
859                                 !sock_flag(sk, SOCK_RCVTSTAMPNS);
860                 break;
861
862         case SO_TIMESTAMPNS:
863                 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
864                 break;
865
866         case SO_TIMESTAMPING:
867                 v.val = 0;
868                 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
869                         v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
870                 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
871                         v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
872                 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
873                         v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
874                 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
875                         v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
876                 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
877                         v.val |= SOF_TIMESTAMPING_SOFTWARE;
878                 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
879                         v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
880                 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
881                         v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
882                 break;
883
884         case SO_RCVTIMEO:
885                 lv = sizeof(struct timeval);
886                 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
887                         v.tm.tv_sec = 0;
888                         v.tm.tv_usec = 0;
889                 } else {
890                         v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
891                         v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
892                 }
893                 break;
894
895         case SO_SNDTIMEO:
896                 lv = sizeof(struct timeval);
897                 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
898                         v.tm.tv_sec = 0;
899                         v.tm.tv_usec = 0;
900                 } else {
901                         v.tm.tv_sec = sk->sk_sndtimeo / HZ;
902                         v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
903                 }
904                 break;
905
906         case SO_RCVLOWAT:
907                 v.val = sk->sk_rcvlowat;
908                 break;
909
910         case SO_SNDLOWAT:
911                 v.val = 1;
912                 break;
913
914         case SO_PASSCRED:
915                 v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
916                 break;
917
918         case SO_PEERCRED:
919         {
920                 struct ucred peercred;
921                 if (len > sizeof(peercred))
922                         len = sizeof(peercred);
923                 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
924                 if (copy_to_user(optval, &peercred, len))
925                         return -EFAULT;
926                 goto lenout;
927         }
928
929         case SO_PEERNAME:
930         {
931                 char address[128];
932
933                 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
934                         return -ENOTCONN;
935                 if (lv < len)
936                         return -EINVAL;
937                 if (copy_to_user(optval, address, len))
938                         return -EFAULT;
939                 goto lenout;
940         }
941
942         /* Dubious BSD thing... Probably nobody even uses it, but
943          * the UNIX standard wants it for whatever reason... -DaveM
944          */
945         case SO_ACCEPTCONN:
946                 v.val = sk->sk_state == TCP_LISTEN;
947                 break;
948
949         case SO_PASSSEC:
950                 v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
951                 break;
952
953         case SO_PEERSEC:
954                 return security_socket_getpeersec_stream(sock, optval, optlen, len);
955
956         case SO_MARK:
957                 v.val = sk->sk_mark;
958                 break;
959
960         case SO_RXQ_OVFL:
961                 v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
962                 break;
963
964         default:
965                 return -ENOPROTOOPT;
966         }
967
968         if (len > lv)
969                 len = lv;
970         if (copy_to_user(optval, &v, len))
971                 return -EFAULT;
972 lenout:
973         if (put_user(len, optlen))
974                 return -EFAULT;
975         return 0;
976 }
977
978 /*
979  * Initialize an sk_lock.
980  *
981  * (We also register the sk_lock with the lock validator.)
982  */
983 static inline void sock_lock_init(struct sock *sk)
984 {
985         sock_lock_init_class_and_name(sk,
986                         af_family_slock_key_strings[sk->sk_family],
987                         af_family_slock_keys + sk->sk_family,
988                         af_family_key_strings[sk->sk_family],
989                         af_family_keys + sk->sk_family);
990 }
991
992 /*
993  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
994  * even temporarly, because of RCU lookups. sk_node should also be left as is.
995  */
996 static 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
1012 static 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
1052 out_free_sec:
1053         security_sk_free(sk);
1054 out_free:
1055         if (slab != NULL)
1056                 kmem_cache_free(slab, sk);
1057         else
1058                 kfree(sk);
1059         return NULL;
1060 }
1061
1062 static 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
1079 void 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 }
1086 EXPORT_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  */
1096 struct 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 }
1118 EXPORT_SYMBOL(sk_alloc);
1119
1120 static 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
1148 void 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 }
1158 EXPORT_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  */
1167 void 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 }
1178 EXPORT_SYMBOL(sk_release_kernel);
1179
1180 struct 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         }
1269 out:
1270         return newsk;
1271 }
1272 EXPORT_SYMBOL_GPL(sk_clone);
1273
1274 void 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 }
1290 EXPORT_SYMBOL_GPL(sk_setup_caps);
1291
1292 void __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  */
1313 void 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 }
1334 EXPORT_SYMBOL(sock_wfree);
1335
1336 /*
1337  * Read buffer destructor automatically called from kfree_skb.
1338  */
1339 void sock_rfree(struct sk_buff *skb)
1340 {
1341         struct sock *sk = skb->sk;
1342
1343         atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
1344         sk_mem_uncharge(skb->sk, skb->truesize);
1345 }
1346 EXPORT_SYMBOL(sock_rfree);
1347
1348
1349 int sock_i_uid(struct sock *sk)
1350 {
1351         int uid;
1352
1353         read_lock(&sk->sk_callback_lock);
1354         uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1355         read_unlock(&sk->sk_callback_lock);
1356         return uid;
1357 }
1358 EXPORT_SYMBOL(sock_i_uid);
1359
1360 unsigned long sock_i_ino(struct sock *sk)
1361 {
1362         unsigned long ino;
1363
1364         read_lock(&sk->sk_callback_lock);
1365         ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1366         read_unlock(&sk->sk_callback_lock);
1367         return ino;
1368 }
1369 EXPORT_SYMBOL(sock_i_ino);
1370
1371 /*
1372  * Allocate a skb from the socket's send buffer.
1373  */
1374 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1375                              gfp_t priority)
1376 {
1377         if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1378                 struct sk_buff *skb = alloc_skb(size, priority);
1379                 if (skb) {
1380                         skb_set_owner_w(skb, sk);
1381                         return skb;
1382                 }
1383         }
1384         return NULL;
1385 }
1386 EXPORT_SYMBOL(sock_wmalloc);
1387
1388 /*
1389  * Allocate a skb from the socket's receive buffer.
1390  */
1391 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1392                              gfp_t priority)
1393 {
1394         if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1395                 struct sk_buff *skb = alloc_skb(size, priority);
1396                 if (skb) {
1397                         skb_set_owner_r(skb, sk);
1398                         return skb;
1399                 }
1400         }
1401         return NULL;
1402 }
1403
1404 /*
1405  * Allocate a memory block from the socket's option memory buffer.
1406  */
1407 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1408 {
1409         if ((unsigned)size <= sysctl_optmem_max &&
1410             atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1411                 void *mem;
1412                 /* First do the add, to avoid the race if kmalloc
1413                  * might sleep.
1414                  */
1415                 atomic_add(size, &sk->sk_omem_alloc);
1416                 mem = kmalloc(size, priority);
1417                 if (mem)
1418                         return mem;
1419                 atomic_sub(size, &sk->sk_omem_alloc);
1420         }
1421         return NULL;
1422 }
1423 EXPORT_SYMBOL(sock_kmalloc);
1424
1425 /*
1426  * Free an option memory block.
1427  */
1428 void sock_kfree_s(struct sock *sk, void *mem, int size)
1429 {
1430         kfree(mem);
1431         atomic_sub(size, &sk->sk_omem_alloc);
1432 }
1433 EXPORT_SYMBOL(sock_kfree_s);
1434
1435 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1436    I think, these locks should be removed for datagram sockets.
1437  */
1438 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1439 {
1440         DEFINE_WAIT(wait);
1441
1442         clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1443         for (;;) {
1444                 if (!timeo)
1445                         break;
1446                 if (signal_pending(current))
1447                         break;
1448                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1449                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1450                 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1451                         break;
1452                 if (sk->sk_shutdown & SEND_SHUTDOWN)
1453                         break;
1454                 if (sk->sk_err)
1455                         break;
1456                 timeo = schedule_timeout(timeo);
1457         }
1458         finish_wait(sk_sleep(sk), &wait);
1459         return timeo;
1460 }
1461
1462
1463 /*
1464  *      Generic send/receive buffer handlers
1465  */
1466
1467 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1468                                      unsigned long data_len, int noblock,
1469                                      int *errcode)
1470 {
1471         struct sk_buff *skb;
1472         gfp_t gfp_mask;
1473         long timeo;
1474         int err;
1475
1476         gfp_mask = sk->sk_allocation;
1477         if (gfp_mask & __GFP_WAIT)
1478                 gfp_mask |= __GFP_REPEAT;
1479
1480         timeo = sock_sndtimeo(sk, noblock);
1481         while (1) {
1482                 err = sock_error(sk);
1483                 if (err != 0)
1484                         goto failure;
1485
1486                 err = -EPIPE;
1487                 if (sk->sk_shutdown & SEND_SHUTDOWN)
1488                         goto failure;
1489
1490                 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1491                         skb = alloc_skb(header_len, gfp_mask);
1492                         if (skb) {
1493                                 int npages;
1494                                 int i;
1495
1496                                 /* No pages, we're done... */
1497                                 if (!data_len)
1498                                         break;
1499
1500                                 npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1501                                 skb->truesize += data_len;
1502                                 skb_shinfo(skb)->nr_frags = npages;
1503                                 for (i = 0; i < npages; i++) {
1504                                         struct page *page;
1505                                         skb_frag_t *frag;
1506
1507                                         page = alloc_pages(sk->sk_allocation, 0);
1508                                         if (!page) {
1509                                                 err = -ENOBUFS;
1510                                                 skb_shinfo(skb)->nr_frags = i;
1511                                                 kfree_skb(skb);
1512                                                 goto failure;
1513                                         }
1514
1515                                         frag = &skb_shinfo(skb)->frags[i];
1516                                         frag->page = page;
1517                                         frag->page_offset = 0;
1518                                         frag->size = (data_len >= PAGE_SIZE ?
1519                                                       PAGE_SIZE :
1520                                                       data_len);
1521                                         data_len -= PAGE_SIZE;
1522                                 }
1523
1524                                 /* Full success... */
1525                                 break;
1526                         }
1527                         err = -ENOBUFS;
1528                         goto failure;
1529                 }
1530                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1531                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1532                 err = -EAGAIN;
1533                 if (!timeo)
1534                         goto failure;
1535                 if (signal_pending(current))
1536                         goto interrupted;
1537                 timeo = sock_wait_for_wmem(sk, timeo);
1538         }
1539
1540         skb_set_owner_w(skb, sk);
1541         return skb;
1542
1543 interrupted:
1544         err = sock_intr_errno(timeo);
1545 failure:
1546         *errcode = err;
1547         return NULL;
1548 }
1549 EXPORT_SYMBOL(sock_alloc_send_pskb);
1550
1551 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1552                                     int noblock, int *errcode)
1553 {
1554         return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1555 }
1556 EXPORT_SYMBOL(sock_alloc_send_skb);
1557
1558 static void __lock_sock(struct sock *sk)
1559 {
1560         DEFINE_WAIT(wait);
1561
1562         for (;;) {
1563                 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1564                                         TASK_UNINTERRUPTIBLE);
1565                 spin_unlock_bh(&sk->sk_lock.slock);
1566                 schedule();
1567                 spin_lock_bh(&sk->sk_lock.slock);
1568                 if (!sock_owned_by_user(sk))
1569                         break;
1570         }
1571         finish_wait(&sk->sk_lock.wq, &wait);
1572 }
1573
1574 static void __release_sock(struct sock *sk)
1575 {
1576         struct sk_buff *skb = sk->sk_backlog.head;
1577
1578         do {
1579                 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1580                 bh_unlock_sock(sk);
1581
1582                 do {
1583                         struct sk_buff *next = skb->next;
1584
1585                         WARN_ON_ONCE(skb_dst_is_noref(skb));
1586                         skb->next = NULL;
1587                         sk_backlog_rcv(sk, skb);
1588
1589                         /*
1590                          * We are in process context here with softirqs
1591                          * disabled, use cond_resched_softirq() to preempt.
1592                          * This is safe to do because we've taken the backlog
1593                          * queue private:
1594                          */
1595                         cond_resched_softirq();
1596
1597                         skb = next;
1598                 } while (skb != NULL);
1599
1600                 bh_lock_sock(sk);
1601         } while ((skb = sk->sk_backlog.head) != NULL);
1602
1603         /*
1604          * Doing the zeroing here guarantee we can not loop forever
1605          * while a wild producer attempts to flood us.
1606          */
1607         sk->sk_backlog.len = 0;
1608 }
1609
1610 /**
1611  * sk_wait_data - wait for data to arrive at sk_receive_queue
1612  * @sk:    sock to wait on
1613  * @timeo: for how long
1614  *
1615  * Now socket state including sk->sk_err is changed only under lock,
1616  * hence we may omit checks after joining wait queue.
1617  * We check receive queue before schedule() only as optimization;
1618  * it is very likely that release_sock() added new data.
1619  */
1620 int sk_wait_data(struct sock *sk, long *timeo)
1621 {
1622         int rc;
1623         DEFINE_WAIT(wait);
1624
1625         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1626         set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1627         rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1628         clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1629         finish_wait(sk_sleep(sk), &wait);
1630         return rc;
1631 }
1632 EXPORT_SYMBOL(sk_wait_data);
1633
1634 /**
1635  *      __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1636  *      @sk: socket
1637  *      @size: memory size to allocate
1638  *      @kind: allocation type
1639  *
1640  *      If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1641  *      rmem allocation. This function assumes that protocols which have
1642  *      memory_pressure use sk_wmem_queued as write buffer accounting.
1643  */
1644 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1645 {
1646         struct proto *prot = sk->sk_prot;
1647         int amt = sk_mem_pages(size);
1648         int allocated;
1649
1650         sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1651         allocated = atomic_add_return(amt, prot->memory_allocated);
1652
1653         /* Under limit. */
1654         if (allocated <= prot->sysctl_mem[0]) {
1655                 if (prot->memory_pressure && *prot->memory_pressure)
1656                         *prot->memory_pressure = 0;
1657                 return 1;
1658         }
1659
1660         /* Under pressure. */
1661         if (allocated > prot->sysctl_mem[1])
1662                 if (prot->enter_memory_pressure)
1663                         prot->enter_memory_pressure(sk);
1664
1665         /* Over hard limit. */
1666         if (allocated > prot->sysctl_mem[2])
1667                 goto suppress_allocation;
1668
1669         /* guarantee minimum buffer size under pressure */
1670         if (kind == SK_MEM_RECV) {
1671                 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1672                         return 1;
1673         } else { /* SK_MEM_SEND */
1674                 if (sk->sk_type == SOCK_STREAM) {
1675                         if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1676                                 return 1;
1677                 } else if (atomic_read(&sk->sk_wmem_alloc) <
1678                            prot->sysctl_wmem[0])
1679                                 return 1;
1680         }
1681
1682         if (prot->memory_pressure) {
1683                 int alloc;
1684
1685                 if (!*prot->memory_pressure)
1686                         return 1;
1687                 alloc = percpu_counter_read_positive(prot->sockets_allocated);
1688                 if (prot->sysctl_mem[2] > alloc *
1689                     sk_mem_pages(sk->sk_wmem_queued +
1690                                  atomic_read(&sk->sk_rmem_alloc) +
1691                                  sk->sk_forward_alloc))
1692                         return 1;
1693         }
1694
1695 suppress_allocation:
1696
1697         if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1698                 sk_stream_moderate_sndbuf(sk);
1699
1700                 /* Fail only if socket is _under_ its sndbuf.
1701                  * In this case we cannot block, so that we have to fail.
1702                  */
1703                 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1704                         return 1;
1705         }
1706
1707         /* Alas. Undo changes. */
1708         sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1709         atomic_sub(amt, prot->memory_allocated);
1710         return 0;
1711 }
1712 EXPORT_SYMBOL(__sk_mem_schedule);
1713
1714 /**
1715  *      __sk_reclaim - reclaim memory_allocated
1716  *      @sk: socket
1717  */
1718 void __sk_mem_reclaim(struct sock *sk)
1719 {
1720         struct proto *prot = sk->sk_prot;
1721
1722         atomic_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1723                    prot->memory_allocated);
1724         sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1725
1726         if (prot->memory_pressure && *prot->memory_pressure &&
1727             (atomic_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1728                 *prot->memory_pressure = 0;
1729 }
1730 EXPORT_SYMBOL(__sk_mem_reclaim);
1731
1732
1733 /*
1734  * Set of default routines for initialising struct proto_ops when
1735  * the protocol does not support a particular function. In certain
1736  * cases where it makes no sense for a protocol to have a "do nothing"
1737  * function, some default processing is provided.
1738  */
1739
1740 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1741 {
1742         return -EOPNOTSUPP;
1743 }
1744 EXPORT_SYMBOL(sock_no_bind);
1745
1746 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1747                     int len, int flags)
1748 {
1749         return -EOPNOTSUPP;
1750 }
1751 EXPORT_SYMBOL(sock_no_connect);
1752
1753 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1754 {
1755         return -EOPNOTSUPP;
1756 }
1757 EXPORT_SYMBOL(sock_no_socketpair);
1758
1759 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1760 {
1761         return -EOPNOTSUPP;
1762 }
1763 EXPORT_SYMBOL(sock_no_accept);
1764
1765 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1766                     int *len, int peer)
1767 {
1768         return -EOPNOTSUPP;
1769 }
1770 EXPORT_SYMBOL(sock_no_getname);
1771
1772 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1773 {
1774         return 0;
1775 }
1776 EXPORT_SYMBOL(sock_no_poll);
1777
1778 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1779 {
1780         return -EOPNOTSUPP;
1781 }
1782 EXPORT_SYMBOL(sock_no_ioctl);
1783
1784 int sock_no_listen(struct socket *sock, int backlog)
1785 {
1786         return -EOPNOTSUPP;
1787 }
1788 EXPORT_SYMBOL(sock_no_listen);
1789
1790 int sock_no_shutdown(struct socket *sock, int how)
1791 {
1792         return -EOPNOTSUPP;
1793 }
1794 EXPORT_SYMBOL(sock_no_shutdown);
1795
1796 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1797                     char __user *optval, unsigned int optlen)
1798 {
1799         return -EOPNOTSUPP;
1800 }
1801 EXPORT_SYMBOL(sock_no_setsockopt);
1802
1803 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1804                     char __user *optval, int __user *optlen)
1805 {
1806         return -EOPNOTSUPP;
1807 }
1808 EXPORT_SYMBOL(sock_no_getsockopt);
1809
1810 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1811                     size_t len)
1812 {
1813         return -EOPNOTSUPP;
1814 }
1815 EXPORT_SYMBOL(sock_no_sendmsg);
1816
1817 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1818                     size_t len, int flags)
1819 {
1820         return -EOPNOTSUPP;
1821 }
1822 EXPORT_SYMBOL(sock_no_recvmsg);
1823
1824 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1825 {
1826         /* Mirror missing mmap method error code */
1827         return -ENODEV;
1828 }
1829 EXPORT_SYMBOL(sock_no_mmap);
1830
1831 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1832 {
1833         ssize_t res;
1834         struct msghdr msg = {.msg_flags = flags};
1835         struct kvec iov;
1836         char *kaddr = kmap(page);
1837         iov.iov_base = kaddr + offset;
1838         iov.iov_len = size;
1839         res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1840         kunmap(page);
1841         return res;
1842 }
1843 EXPORT_SYMBOL(sock_no_sendpage);
1844
1845 /*
1846  *      Default Socket Callbacks
1847  */
1848
1849 static void sock_def_wakeup(struct sock *sk)
1850 {
1851         struct socket_wq *wq;
1852
1853         rcu_read_lock();
1854         wq = rcu_dereference(sk->sk_wq);
1855         if (wq_has_sleeper(wq))
1856                 wake_up_interruptible_all(&wq->wait);
1857         rcu_read_unlock();
1858 }
1859
1860 static void sock_def_error_report(struct sock *sk)
1861 {
1862         struct socket_wq *wq;
1863
1864         rcu_read_lock();
1865         wq = rcu_dereference(sk->sk_wq);
1866         if (wq_has_sleeper(wq))
1867                 wake_up_interruptible_poll(&wq->wait, POLLERR);
1868         sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1869         rcu_read_unlock();
1870 }
1871
1872 static void sock_def_readable(struct sock *sk, int len)
1873 {
1874         struct socket_wq *wq;
1875
1876         rcu_read_lock();
1877         wq = rcu_dereference(sk->sk_wq);
1878         if (wq_has_sleeper(wq))
1879                 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
1880                                                 POLLRDNORM | POLLRDBAND);
1881         sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1882         rcu_read_unlock();
1883 }
1884
1885 static void sock_def_write_space(struct sock *sk)
1886 {
1887         struct socket_wq *wq;
1888
1889         rcu_read_lock();
1890
1891         /* Do not wake up a writer until he can make "significant"
1892          * progress.  --DaveM
1893          */
1894         if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1895                 wq = rcu_dereference(sk->sk_wq);
1896                 if (wq_has_sleeper(wq))
1897                         wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1898                                                 POLLWRNORM | POLLWRBAND);
1899
1900                 /* Should agree with poll, otherwise some programs break */
1901                 if (sock_writeable(sk))
1902                         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1903         }
1904
1905         rcu_read_unlock();
1906 }
1907
1908 static void sock_def_destruct(struct sock *sk)
1909 {
1910         kfree(sk->sk_protinfo);
1911 }
1912
1913 void sk_send_sigurg(struct sock *sk)
1914 {
1915         if (sk->sk_socket && sk->sk_socket->file)
1916                 if (send_sigurg(&sk->sk_socket->file->f_owner))
1917                         sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1918 }
1919 EXPORT_SYMBOL(sk_send_sigurg);
1920
1921 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1922                     unsigned long expires)
1923 {
1924         if (!mod_timer(timer, expires))
1925                 sock_hold(sk);
1926 }
1927 EXPORT_SYMBOL(sk_reset_timer);
1928
1929 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1930 {
1931         if (timer_pending(timer) && del_timer(timer))
1932                 __sock_put(sk);
1933 }
1934 EXPORT_SYMBOL(sk_stop_timer);
1935
1936 void sock_init_data(struct socket *sock, struct sock *sk)
1937 {
1938         skb_queue_head_init(&sk->sk_receive_queue);
1939         skb_queue_head_init(&sk->sk_write_queue);
1940         skb_queue_head_init(&sk->sk_error_queue);
1941 #ifdef CONFIG_NET_DMA
1942         skb_queue_head_init(&sk->sk_async_wait_queue);
1943 #endif
1944
1945         sk->sk_send_head        =       NULL;
1946
1947         init_timer(&sk->sk_timer);
1948
1949         sk->sk_allocation       =       GFP_KERNEL;
1950         sk->sk_rcvbuf           =       sysctl_rmem_default;
1951         sk->sk_sndbuf           =       sysctl_wmem_default;
1952         sk->sk_state            =       TCP_CLOSE;
1953         sk_set_socket(sk, sock);
1954
1955         sock_set_flag(sk, SOCK_ZAPPED);
1956
1957         if (sock) {
1958                 sk->sk_type     =       sock->type;
1959                 sk->sk_wq       =       sock->wq;
1960                 sock->sk        =       sk;
1961         } else
1962                 sk->sk_wq       =       NULL;
1963
1964         spin_lock_init(&sk->sk_dst_lock);
1965         rwlock_init(&sk->sk_callback_lock);
1966         lockdep_set_class_and_name(&sk->sk_callback_lock,
1967                         af_callback_keys + sk->sk_family,
1968                         af_family_clock_key_strings[sk->sk_family]);
1969
1970         sk->sk_state_change     =       sock_def_wakeup;
1971         sk->sk_data_ready       =       sock_def_readable;
1972         sk->sk_write_space      =       sock_def_write_space;
1973         sk->sk_error_report     =       sock_def_error_report;
1974         sk->sk_destruct         =       sock_def_destruct;
1975
1976         sk->sk_sndmsg_page      =       NULL;
1977         sk->sk_sndmsg_off       =       0;
1978
1979         sk->sk_peer_pid         =       NULL;
1980         sk->sk_peer_cred        =       NULL;
1981         sk->sk_write_pending    =       0;
1982         sk->sk_rcvlowat         =       1;
1983         sk->sk_rcvtimeo         =       MAX_SCHEDULE_TIMEOUT;
1984         sk->sk_sndtimeo         =       MAX_SCHEDULE_TIMEOUT;
1985
1986         sk->sk_stamp = ktime_set(-1L, 0);
1987
1988         /*
1989          * Before updating sk_refcnt, we must commit prior changes to memory
1990          * (Documentation/RCU/rculist_nulls.txt for details)
1991          */
1992         smp_wmb();
1993         atomic_set(&sk->sk_refcnt, 1);
1994         atomic_set(&sk->sk_drops, 0);
1995 }
1996 EXPORT_SYMBOL(sock_init_data);
1997
1998 void lock_sock_nested(struct sock *sk, int subclass)
1999 {
2000         might_sleep();
2001         spin_lock_bh(&sk->sk_lock.slock);
2002         if (sk->sk_lock.owned)
2003                 __lock_sock(sk);
2004         sk->sk_lock.owned = 1;
2005         spin_unlock(&sk->sk_lock.slock);
2006         /*
2007          * The sk_lock has mutex_lock() semantics here:
2008          */
2009         mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2010         local_bh_enable();
2011 }
2012 EXPORT_SYMBOL(lock_sock_nested);
2013
2014 void release_sock(struct sock *sk)
2015 {
2016         /*
2017          * The sk_lock has mutex_unlock() semantics:
2018          */
2019         mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2020
2021         spin_lock_bh(&sk->sk_lock.slock);
2022         if (sk->sk_backlog.tail)
2023                 __release_sock(sk);
2024         sk->sk_lock.owned = 0;
2025         if (waitqueue_active(&sk->sk_lock.wq))
2026                 wake_up(&sk->sk_lock.wq);
2027         spin_unlock_bh(&sk->sk_lock.slock);
2028 }
2029 EXPORT_SYMBOL(release_sock);
2030
2031 /**
2032  * lock_sock_fast - fast version of lock_sock
2033  * @sk: socket
2034  *
2035  * This version should be used for very small section, where process wont block
2036  * return false if fast path is taken
2037  *   sk_lock.slock locked, owned = 0, BH disabled
2038  * return true if slow path is taken
2039  *   sk_lock.slock unlocked, owned = 1, BH enabled
2040  */
2041 bool lock_sock_fast(struct sock *sk)
2042 {
2043         might_sleep();
2044         spin_lock_bh(&sk->sk_lock.slock);
2045
2046         if (!sk->sk_lock.owned)
2047                 /*
2048                  * Note : We must disable BH
2049                  */
2050                 return false;
2051
2052         __lock_sock(sk);
2053         sk->sk_lock.owned = 1;
2054         spin_unlock(&sk->sk_lock.slock);
2055         /*
2056          * The sk_lock has mutex_lock() semantics here:
2057          */
2058         mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2059         local_bh_enable();
2060         return true;
2061 }
2062 EXPORT_SYMBOL(lock_sock_fast);
2063
2064 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2065 {
2066         struct timeval tv;
2067         if (!sock_flag(sk, SOCK_TIMESTAMP))
2068                 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2069         tv = ktime_to_timeval(sk->sk_stamp);
2070         if (tv.tv_sec == -1)
2071                 return -ENOENT;
2072         if (tv.tv_sec == 0) {
2073                 sk->sk_stamp = ktime_get_real();
2074                 tv = ktime_to_timeval(sk->sk_stamp);
2075         }
2076         return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2077 }
2078 EXPORT_SYMBOL(sock_get_timestamp);
2079
2080 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2081 {
2082         struct timespec ts;
2083         if (!sock_flag(sk, SOCK_TIMESTAMP))
2084                 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2085         ts = ktime_to_timespec(sk->sk_stamp);
2086         if (ts.tv_sec == -1)
2087                 return -ENOENT;
2088         if (ts.tv_sec == 0) {
2089                 sk->sk_stamp = ktime_get_real();
2090                 ts = ktime_to_timespec(sk->sk_stamp);
2091         }
2092         return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2093 }
2094 EXPORT_SYMBOL(sock_get_timestampns);
2095
2096 void sock_enable_timestamp(struct sock *sk, int flag)
2097 {
2098         if (!sock_flag(sk, flag)) {
2099                 sock_set_flag(sk, flag);
2100                 /*
2101                  * we just set one of the two flags which require net
2102                  * time stamping, but time stamping might have been on
2103                  * already because of the other one
2104                  */
2105                 if (!sock_flag(sk,
2106                                 flag == SOCK_TIMESTAMP ?
2107                                 SOCK_TIMESTAMPING_RX_SOFTWARE :
2108                                 SOCK_TIMESTAMP))
2109                         net_enable_timestamp();
2110         }
2111 }
2112
2113 /*
2114  *      Get a socket option on an socket.
2115  *
2116  *      FIX: POSIX 1003.1g is very ambiguous here. It states that
2117  *      asynchronous errors should be reported by getsockopt. We assume
2118  *      this means if you specify SO_ERROR (otherwise whats the point of it).
2119  */
2120 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2121                            char __user *optval, int __user *optlen)
2122 {
2123         struct sock *sk = sock->sk;
2124
2125         return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2126 }
2127 EXPORT_SYMBOL(sock_common_getsockopt);
2128
2129 #ifdef CONFIG_COMPAT
2130 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2131                                   char __user *optval, int __user *optlen)
2132 {
2133         struct sock *sk = sock->sk;
2134
2135         if (sk->sk_prot->compat_getsockopt != NULL)
2136                 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2137                                                       optval, optlen);
2138         return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2139 }
2140 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2141 #endif
2142
2143 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2144                         struct msghdr *msg, size_t size, int flags)
2145 {
2146         struct sock *sk = sock->sk;
2147         int addr_len = 0;
2148         int err;
2149
2150         err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2151                                    flags & ~MSG_DONTWAIT, &addr_len);
2152         if (err >= 0)
2153                 msg->msg_namelen = addr_len;
2154         return err;
2155 }
2156 EXPORT_SYMBOL(sock_common_recvmsg);
2157
2158 /*
2159  *      Set socket options on an inet socket.
2160  */
2161 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2162                            char __user *optval, unsigned int optlen)
2163 {
2164         struct sock *sk = sock->sk;
2165
2166         return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2167 }
2168 EXPORT_SYMBOL(sock_common_setsockopt);
2169
2170 #ifdef CONFIG_COMPAT
2171 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2172                                   char __user *optval, unsigned int optlen)
2173 {
2174         struct sock *sk = sock->sk;
2175
2176         if (sk->sk_prot->compat_setsockopt != NULL)
2177                 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2178                                                       optval, optlen);
2179         return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2180 }
2181 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2182 #endif
2183
2184 void sk_common_release(struct sock *sk)
2185 {
2186         if (sk->sk_prot->destroy)
2187                 sk->sk_prot->destroy(sk);
2188
2189         /*
2190          * Observation: when sock_common_release is called, processes have
2191          * no access to socket. But net still has.
2192          * Step one, detach it from networking:
2193          *
2194          * A. Remove from hash tables.
2195          */
2196
2197         sk->sk_prot->unhash(sk);
2198
2199         /*
2200          * In this point socket cannot receive new packets, but it is possible
2201          * that some packets are in flight because some CPU runs receiver and
2202          * did hash table lookup before we unhashed socket. They will achieve
2203          * receive queue and will be purged by socket destructor.
2204          *
2205          * Also we still have packets pending on receive queue and probably,
2206          * our own packets waiting in device queues. sock_destroy will drain
2207          * receive queue, but transmitted packets will delay socket destruction
2208          * until the last reference will be released.
2209          */
2210
2211         sock_orphan(sk);
2212
2213         xfrm_sk_free_policy(sk);
2214
2215         sk_refcnt_debug_release(sk);
2216         sock_put(sk);
2217 }
2218 EXPORT_SYMBOL(sk_common_release);
2219
2220 static DEFINE_RWLOCK(proto_list_lock);
2221 static LIST_HEAD(proto_list);
2222
2223 #ifdef CONFIG_PROC_FS
2224 #define PROTO_INUSE_NR  64      /* should be enough for the first time */
2225 struct prot_inuse {
2226         int val[PROTO_INUSE_NR];
2227 };
2228
2229 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2230
2231 #ifdef CONFIG_NET_NS
2232 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2233 {
2234         int cpu = smp_processor_id();
2235         per_cpu_ptr(net->core.inuse, cpu)->val[prot->inuse_idx] += val;
2236 }
2237 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2238
2239 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2240 {
2241         int cpu, idx = prot->inuse_idx;
2242         int res = 0;
2243
2244         for_each_possible_cpu(cpu)
2245                 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2246
2247         return res >= 0 ? res : 0;
2248 }
2249 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2250
2251 static int __net_init sock_inuse_init_net(struct net *net)
2252 {
2253         net->core.inuse = alloc_percpu(struct prot_inuse);
2254         return net->core.inuse ? 0 : -ENOMEM;
2255 }
2256
2257 static void __net_exit sock_inuse_exit_net(struct net *net)
2258 {
2259         free_percpu(net->core.inuse);
2260 }
2261
2262 static struct pernet_operations net_inuse_ops = {
2263         .init = sock_inuse_init_net,
2264         .exit = sock_inuse_exit_net,
2265 };
2266
2267 static __init int net_inuse_init(void)
2268 {
2269         if (register_pernet_subsys(&net_inuse_ops))
2270                 panic("Cannot initialize net inuse counters");
2271
2272         return 0;
2273 }
2274
2275 core_initcall(net_inuse_init);
2276 #else
2277 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2278
2279 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2280 {
2281         __get_cpu_var(prot_inuse).val[prot->inuse_idx] += val;
2282 }
2283 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2284
2285 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2286 {
2287         int cpu, idx = prot->inuse_idx;
2288         int res = 0;
2289
2290         for_each_possible_cpu(cpu)
2291                 res += per_cpu(prot_inuse, cpu).val[idx];
2292
2293         return res >= 0 ? res : 0;
2294 }
2295 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2296 #endif
2297
2298 static void assign_proto_idx(struct proto *prot)
2299 {
2300         prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2301
2302         if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2303                 printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2304                 return;
2305         }
2306
2307         set_bit(prot->inuse_idx, proto_inuse_idx);
2308 }
2309
2310 static void release_proto_idx(struct proto *prot)
2311 {
2312         if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2313                 clear_bit(prot->inuse_idx, proto_inuse_idx);
2314 }
2315 #else
2316 static inline void assign_proto_idx(struct proto *prot)
2317 {
2318 }
2319
2320 static inline void release_proto_idx(struct proto *prot)
2321 {
2322 }
2323 #endif
2324
2325 int proto_register(struct proto *prot, int alloc_slab)
2326 {
2327         if (alloc_slab) {
2328                 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2329                                         SLAB_HWCACHE_ALIGN | prot->slab_flags,
2330                                         NULL);
2331
2332                 if (prot->slab == NULL) {
2333                         printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2334                                prot->name);
2335                         goto out;
2336                 }
2337
2338                 if (prot->rsk_prot != NULL) {
2339                         prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2340                         if (prot->rsk_prot->slab_name == NULL)
2341                                 goto out_free_sock_slab;
2342
2343                         prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2344                                                                  prot->rsk_prot->obj_size, 0,
2345                                                                  SLAB_HWCACHE_ALIGN, NULL);
2346
2347                         if (prot->rsk_prot->slab == NULL) {
2348                                 printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2349                                        prot->name);
2350                                 goto out_free_request_sock_slab_name;
2351                         }
2352                 }
2353
2354                 if (prot->twsk_prot != NULL) {
2355                         prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2356
2357                         if (prot->twsk_prot->twsk_slab_name == NULL)
2358                                 goto out_free_request_sock_slab;
2359
2360                         prot->twsk_prot->twsk_slab =
2361                                 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2362                                                   prot->twsk_prot->twsk_obj_size,
2363                                                   0,
2364                                                   SLAB_HWCACHE_ALIGN |
2365                                                         prot->slab_flags,
2366                                                   NULL);
2367                         if (prot->twsk_prot->twsk_slab == NULL)
2368                                 goto out_free_timewait_sock_slab_name;
2369                 }
2370         }
2371
2372         write_lock(&proto_list_lock);
2373         list_add(&prot->node, &proto_list);
2374         assign_proto_idx(prot);
2375         write_unlock(&proto_list_lock);
2376         return 0;
2377
2378 out_free_timewait_sock_slab_name:
2379         kfree(prot->twsk_prot->twsk_slab_name);
2380 out_free_request_sock_slab:
2381         if (prot->rsk_prot && prot->rsk_prot->slab) {
2382                 kmem_cache_destroy(prot->rsk_prot->slab);
2383                 prot->rsk_prot->slab = NULL;
2384         }
2385 out_free_request_sock_slab_name:
2386         if (prot->rsk_prot)
2387                 kfree(prot->rsk_prot->slab_name);
2388 out_free_sock_slab:
2389         kmem_cache_destroy(prot->slab);
2390         prot->slab = NULL;
2391 out:
2392         return -ENOBUFS;
2393 }
2394 EXPORT_SYMBOL(proto_register);
2395
2396 void proto_unregister(struct proto *prot)
2397 {
2398         write_lock(&proto_list_lock);
2399         release_proto_idx(prot);
2400         list_del(&prot->node);
2401         write_unlock(&proto_list_lock);
2402
2403         if (prot->slab != NULL) {
2404                 kmem_cache_destroy(prot->slab);
2405                 prot->slab = NULL;
2406         }
2407
2408         if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2409                 kmem_cache_destroy(prot->rsk_prot->slab);
2410                 kfree(prot->rsk_prot->slab_name);
2411                 prot->rsk_prot->slab = NULL;
2412         }
2413
2414         if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2415                 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2416                 kfree(prot->twsk_prot->twsk_slab_name);
2417                 prot->twsk_prot->twsk_slab = NULL;
2418         }
2419 }
2420 EXPORT_SYMBOL(proto_unregister);
2421
2422 #ifdef CONFIG_PROC_FS
2423 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2424         __acquires(proto_list_lock)
2425 {
2426         read_lock(&proto_list_lock);
2427         return seq_list_start_head(&proto_list, *pos);
2428 }
2429
2430 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2431 {
2432         return seq_list_next(v, &proto_list, pos);
2433 }
2434
2435 static void proto_seq_stop(struct seq_file *seq, void *v)
2436         __releases(proto_list_lock)
2437 {
2438         read_unlock(&proto_list_lock);
2439 }
2440
2441 static char proto_method_implemented(const void *method)
2442 {
2443         return method == NULL ? 'n' : 'y';
2444 }
2445
2446 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2447 {
2448         seq_printf(seq, "%-9s %4u %6d  %6d   %-3s %6u   %-3s  %-10s "
2449                         "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2450                    proto->name,
2451                    proto->obj_size,
2452                    sock_prot_inuse_get(seq_file_net(seq), proto),
2453                    proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
2454                    proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2455                    proto->max_header,
2456                    proto->slab == NULL ? "no" : "yes",
2457                    module_name(proto->owner),
2458                    proto_method_implemented(proto->close),
2459                    proto_method_implemented(proto->connect),
2460                    proto_method_implemented(proto->disconnect),
2461                    proto_method_implemented(proto->accept),
2462                    proto_method_implemented(proto->ioctl),
2463                    proto_method_implemented(proto->init),
2464                    proto_method_implemented(proto->destroy),
2465                    proto_method_implemented(proto->shutdown),
2466                    proto_method_implemented(proto->setsockopt),
2467                    proto_method_implemented(proto->getsockopt),
2468                    proto_method_implemented(proto->sendmsg),
2469                    proto_method_implemented(proto->recvmsg),
2470                    proto_method_implemented(proto->sendpage),
2471                    proto_method_implemented(proto->bind),
2472                    proto_method_implemented(proto->backlog_rcv),
2473                    proto_method_implemented(proto->hash),
2474                    proto_method_implemented(proto->unhash),
2475                    proto_method_implemented(proto->get_port),
2476                    proto_method_implemented(proto->enter_memory_pressure));
2477 }
2478
2479 static int proto_seq_show(struct seq_file *seq, void *v)
2480 {
2481         if (v == &proto_list)
2482                 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2483                            "protocol",
2484                            "size",
2485                            "sockets",
2486                            "memory",
2487                            "press",
2488                            "maxhdr",
2489                            "slab",
2490                            "module",
2491                            "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2492         else
2493                 proto_seq_printf(seq, list_entry(v, struct proto, node));
2494         return 0;
2495 }
2496
2497 static const struct seq_operations proto_seq_ops = {
2498         .start  = proto_seq_start,
2499         .next   = proto_seq_next,
2500         .stop   = proto_seq_stop,
2501         .show   = proto_seq_show,
2502 };
2503
2504 static int proto_seq_open(struct inode *inode, struct file *file)
2505 {
2506         return seq_open_net(inode, file, &proto_seq_ops,
2507                             sizeof(struct seq_net_private));
2508 }
2509
2510 static const struct file_operations proto_seq_fops = {
2511         .owner          = THIS_MODULE,
2512         .open           = proto_seq_open,
2513         .read           = seq_read,
2514         .llseek         = seq_lseek,
2515         .release        = seq_release_net,
2516 };
2517
2518 static __net_init int proto_init_net(struct net *net)
2519 {
2520         if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2521                 return -ENOMEM;
2522
2523         return 0;
2524 }
2525
2526 static __net_exit void proto_exit_net(struct net *net)
2527 {
2528         proc_net_remove(net, "protocols");
2529 }
2530
2531
2532 static __net_initdata struct pernet_operations proto_net_ops = {
2533         .init = proto_init_net,
2534         .exit = proto_exit_net,
2535 };
2536
2537 static int __init proto_init(void)
2538 {
2539         return register_pernet_subsys(&proto_net_ops);
2540 }
2541
2542 subsys_initcall(proto_init);
2543
2544 #endif /* PROC_FS */