3eed5424e659a1ab130324d16bfe3c0af4ab2feb
[linux-3.10.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;
1082
1083         rcu_read_lock();  /* doing current task, which cannot vanish. */
1084         classid = task_cls_classid(current);
1085         rcu_read_unlock();
1086         if (classid && classid != sk->sk_classid)
1087                 sk->sk_classid = classid;
1088 }
1089 EXPORT_SYMBOL(sock_update_classid);
1090 #endif
1091
1092 /**
1093  *      sk_alloc - All socket objects are allocated here
1094  *      @net: the applicable net namespace
1095  *      @family: protocol family
1096  *      @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1097  *      @prot: struct proto associated with this new sock instance
1098  */
1099 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1100                       struct proto *prot)
1101 {
1102         struct sock *sk;
1103
1104         sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1105         if (sk) {
1106                 sk->sk_family = family;
1107                 /*
1108                  * See comment in struct sock definition to understand
1109                  * why we need sk_prot_creator -acme
1110                  */
1111                 sk->sk_prot = sk->sk_prot_creator = prot;
1112                 sock_lock_init(sk);
1113                 sock_net_set(sk, get_net(net));
1114                 atomic_set(&sk->sk_wmem_alloc, 1);
1115
1116                 sock_update_classid(sk);
1117         }
1118
1119         return sk;
1120 }
1121 EXPORT_SYMBOL(sk_alloc);
1122
1123 static void __sk_free(struct sock *sk)
1124 {
1125         struct sk_filter *filter;
1126
1127         if (sk->sk_destruct)
1128                 sk->sk_destruct(sk);
1129
1130         filter = rcu_dereference_check(sk->sk_filter,
1131                                        atomic_read(&sk->sk_wmem_alloc) == 0);
1132         if (filter) {
1133                 sk_filter_uncharge(sk, filter);
1134                 rcu_assign_pointer(sk->sk_filter, NULL);
1135         }
1136
1137         sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1138         sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1139
1140         if (atomic_read(&sk->sk_omem_alloc))
1141                 printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1142                        __func__, atomic_read(&sk->sk_omem_alloc));
1143
1144         if (sk->sk_peer_cred)
1145                 put_cred(sk->sk_peer_cred);
1146         put_pid(sk->sk_peer_pid);
1147         put_net(sock_net(sk));
1148         sk_prot_free(sk->sk_prot_creator, sk);
1149 }
1150
1151 void sk_free(struct sock *sk)
1152 {
1153         /*
1154          * We substract one from sk_wmem_alloc and can know if
1155          * some packets are still in some tx queue.
1156          * If not null, sock_wfree() will call __sk_free(sk) later
1157          */
1158         if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1159                 __sk_free(sk);
1160 }
1161 EXPORT_SYMBOL(sk_free);
1162
1163 /*
1164  * Last sock_put should drop referrence to sk->sk_net. It has already
1165  * been dropped in sk_change_net. Taking referrence to stopping namespace
1166  * is not an option.
1167  * Take referrence to a socket to remove it from hash _alive_ and after that
1168  * destroy it in the context of init_net.
1169  */
1170 void sk_release_kernel(struct sock *sk)
1171 {
1172         if (sk == NULL || sk->sk_socket == NULL)
1173                 return;
1174
1175         sock_hold(sk);
1176         sock_release(sk->sk_socket);
1177         release_net(sock_net(sk));
1178         sock_net_set(sk, get_net(&init_net));
1179         sock_put(sk);
1180 }
1181 EXPORT_SYMBOL(sk_release_kernel);
1182
1183 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1184 {
1185         struct sock *newsk;
1186
1187         newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1188         if (newsk != NULL) {
1189                 struct sk_filter *filter;
1190
1191                 sock_copy(newsk, sk);
1192
1193                 /* SANITY */
1194                 get_net(sock_net(newsk));
1195                 sk_node_init(&newsk->sk_node);
1196                 sock_lock_init(newsk);
1197                 bh_lock_sock(newsk);
1198                 newsk->sk_backlog.head  = newsk->sk_backlog.tail = NULL;
1199                 newsk->sk_backlog.len = 0;
1200
1201                 atomic_set(&newsk->sk_rmem_alloc, 0);
1202                 /*
1203                  * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1204                  */
1205                 atomic_set(&newsk->sk_wmem_alloc, 1);
1206                 atomic_set(&newsk->sk_omem_alloc, 0);
1207                 skb_queue_head_init(&newsk->sk_receive_queue);
1208                 skb_queue_head_init(&newsk->sk_write_queue);
1209 #ifdef CONFIG_NET_DMA
1210                 skb_queue_head_init(&newsk->sk_async_wait_queue);
1211 #endif
1212
1213                 spin_lock_init(&newsk->sk_dst_lock);
1214                 rwlock_init(&newsk->sk_callback_lock);
1215                 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1216                                 af_callback_keys + newsk->sk_family,
1217                                 af_family_clock_key_strings[newsk->sk_family]);
1218
1219                 newsk->sk_dst_cache     = NULL;
1220                 newsk->sk_wmem_queued   = 0;
1221                 newsk->sk_forward_alloc = 0;
1222                 newsk->sk_send_head     = NULL;
1223                 newsk->sk_userlocks     = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1224
1225                 sock_reset_flag(newsk, SOCK_DONE);
1226                 skb_queue_head_init(&newsk->sk_error_queue);
1227
1228                 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1229                 if (filter != NULL)
1230                         sk_filter_charge(newsk, filter);
1231
1232                 if (unlikely(xfrm_sk_clone_policy(newsk))) {
1233                         /* It is still raw copy of parent, so invalidate
1234                          * destructor and make plain sk_free() */
1235                         newsk->sk_destruct = NULL;
1236                         sk_free(newsk);
1237                         newsk = NULL;
1238                         goto out;
1239                 }
1240
1241                 newsk->sk_err      = 0;
1242                 newsk->sk_priority = 0;
1243                 /*
1244                  * Before updating sk_refcnt, we must commit prior changes to memory
1245                  * (Documentation/RCU/rculist_nulls.txt for details)
1246                  */
1247                 smp_wmb();
1248                 atomic_set(&newsk->sk_refcnt, 2);
1249
1250                 /*
1251                  * Increment the counter in the same struct proto as the master
1252                  * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1253                  * is the same as sk->sk_prot->socks, as this field was copied
1254                  * with memcpy).
1255                  *
1256                  * This _changes_ the previous behaviour, where
1257                  * tcp_create_openreq_child always was incrementing the
1258                  * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1259                  * to be taken into account in all callers. -acme
1260                  */
1261                 sk_refcnt_debug_inc(newsk);
1262                 sk_set_socket(newsk, NULL);
1263                 newsk->sk_wq = NULL;
1264
1265                 if (newsk->sk_prot->sockets_allocated)
1266                         percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1267
1268                 if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1269                     sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1270                         net_enable_timestamp();
1271         }
1272 out:
1273         return newsk;
1274 }
1275 EXPORT_SYMBOL_GPL(sk_clone);
1276
1277 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1278 {
1279         __sk_dst_set(sk, dst);
1280         sk->sk_route_caps = dst->dev->features;
1281         if (sk->sk_route_caps & NETIF_F_GSO)
1282                 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1283         sk->sk_route_caps &= ~sk->sk_route_nocaps;
1284         if (sk_can_gso(sk)) {
1285                 if (dst->header_len) {
1286                         sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1287                 } else {
1288                         sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1289                         sk->sk_gso_max_size = dst->dev->gso_max_size;
1290                 }
1291         }
1292 }
1293 EXPORT_SYMBOL_GPL(sk_setup_caps);
1294
1295 void __init sk_init(void)
1296 {
1297         if (totalram_pages <= 4096) {
1298                 sysctl_wmem_max = 32767;
1299                 sysctl_rmem_max = 32767;
1300                 sysctl_wmem_default = 32767;
1301                 sysctl_rmem_default = 32767;
1302         } else if (totalram_pages >= 131072) {
1303                 sysctl_wmem_max = 131071;
1304                 sysctl_rmem_max = 131071;
1305         }
1306 }
1307
1308 /*
1309  *      Simple resource managers for sockets.
1310  */
1311
1312
1313 /*
1314  * Write buffer destructor automatically called from kfree_skb.
1315  */
1316 void sock_wfree(struct sk_buff *skb)
1317 {
1318         struct sock *sk = skb->sk;
1319         unsigned int len = skb->truesize;
1320
1321         if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1322                 /*
1323                  * Keep a reference on sk_wmem_alloc, this will be released
1324                  * after sk_write_space() call
1325                  */
1326                 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1327                 sk->sk_write_space(sk);
1328                 len = 1;
1329         }
1330         /*
1331          * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1332          * could not do because of in-flight packets
1333          */
1334         if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1335                 __sk_free(sk);
1336 }
1337 EXPORT_SYMBOL(sock_wfree);
1338
1339 /*
1340  * Read buffer destructor automatically called from kfree_skb.
1341  */
1342 void sock_rfree(struct sk_buff *skb)
1343 {
1344         struct sock *sk = skb->sk;
1345         unsigned int len = skb->truesize;
1346
1347         atomic_sub(len, &sk->sk_rmem_alloc);
1348         sk_mem_uncharge(sk, len);
1349 }
1350 EXPORT_SYMBOL(sock_rfree);
1351
1352
1353 int sock_i_uid(struct sock *sk)
1354 {
1355         int uid;
1356
1357         read_lock_bh(&sk->sk_callback_lock);
1358         uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1359         read_unlock_bh(&sk->sk_callback_lock);
1360         return uid;
1361 }
1362 EXPORT_SYMBOL(sock_i_uid);
1363
1364 unsigned long sock_i_ino(struct sock *sk)
1365 {
1366         unsigned long ino;
1367
1368         read_lock_bh(&sk->sk_callback_lock);
1369         ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1370         read_unlock_bh(&sk->sk_callback_lock);
1371         return ino;
1372 }
1373 EXPORT_SYMBOL(sock_i_ino);
1374
1375 /*
1376  * Allocate a skb from the socket's send buffer.
1377  */
1378 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1379                              gfp_t priority)
1380 {
1381         if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1382                 struct sk_buff *skb = alloc_skb(size, priority);
1383                 if (skb) {
1384                         skb_set_owner_w(skb, sk);
1385                         return skb;
1386                 }
1387         }
1388         return NULL;
1389 }
1390 EXPORT_SYMBOL(sock_wmalloc);
1391
1392 /*
1393  * Allocate a skb from the socket's receive buffer.
1394  */
1395 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1396                              gfp_t priority)
1397 {
1398         if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1399                 struct sk_buff *skb = alloc_skb(size, priority);
1400                 if (skb) {
1401                         skb_set_owner_r(skb, sk);
1402                         return skb;
1403                 }
1404         }
1405         return NULL;
1406 }
1407
1408 /*
1409  * Allocate a memory block from the socket's option memory buffer.
1410  */
1411 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1412 {
1413         if ((unsigned)size <= sysctl_optmem_max &&
1414             atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1415                 void *mem;
1416                 /* First do the add, to avoid the race if kmalloc
1417                  * might sleep.
1418                  */
1419                 atomic_add(size, &sk->sk_omem_alloc);
1420                 mem = kmalloc(size, priority);
1421                 if (mem)
1422                         return mem;
1423                 atomic_sub(size, &sk->sk_omem_alloc);
1424         }
1425         return NULL;
1426 }
1427 EXPORT_SYMBOL(sock_kmalloc);
1428
1429 /*
1430  * Free an option memory block.
1431  */
1432 void sock_kfree_s(struct sock *sk, void *mem, int size)
1433 {
1434         kfree(mem);
1435         atomic_sub(size, &sk->sk_omem_alloc);
1436 }
1437 EXPORT_SYMBOL(sock_kfree_s);
1438
1439 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1440    I think, these locks should be removed for datagram sockets.
1441  */
1442 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1443 {
1444         DEFINE_WAIT(wait);
1445
1446         clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1447         for (;;) {
1448                 if (!timeo)
1449                         break;
1450                 if (signal_pending(current))
1451                         break;
1452                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1453                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1454                 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1455                         break;
1456                 if (sk->sk_shutdown & SEND_SHUTDOWN)
1457                         break;
1458                 if (sk->sk_err)
1459                         break;
1460                 timeo = schedule_timeout(timeo);
1461         }
1462         finish_wait(sk_sleep(sk), &wait);
1463         return timeo;
1464 }
1465
1466
1467 /*
1468  *      Generic send/receive buffer handlers
1469  */
1470
1471 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1472                                      unsigned long data_len, int noblock,
1473                                      int *errcode)
1474 {
1475         struct sk_buff *skb;
1476         gfp_t gfp_mask;
1477         long timeo;
1478         int err;
1479
1480         gfp_mask = sk->sk_allocation;
1481         if (gfp_mask & __GFP_WAIT)
1482                 gfp_mask |= __GFP_REPEAT;
1483
1484         timeo = sock_sndtimeo(sk, noblock);
1485         while (1) {
1486                 err = sock_error(sk);
1487                 if (err != 0)
1488                         goto failure;
1489
1490                 err = -EPIPE;
1491                 if (sk->sk_shutdown & SEND_SHUTDOWN)
1492                         goto failure;
1493
1494                 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1495                         skb = alloc_skb(header_len, gfp_mask);
1496                         if (skb) {
1497                                 int npages;
1498                                 int i;
1499
1500                                 /* No pages, we're done... */
1501                                 if (!data_len)
1502                                         break;
1503
1504                                 npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1505                                 skb->truesize += data_len;
1506                                 skb_shinfo(skb)->nr_frags = npages;
1507                                 for (i = 0; i < npages; i++) {
1508                                         struct page *page;
1509                                         skb_frag_t *frag;
1510
1511                                         page = alloc_pages(sk->sk_allocation, 0);
1512                                         if (!page) {
1513                                                 err = -ENOBUFS;
1514                                                 skb_shinfo(skb)->nr_frags = i;
1515                                                 kfree_skb(skb);
1516                                                 goto failure;
1517                                         }
1518
1519                                         frag = &skb_shinfo(skb)->frags[i];
1520                                         frag->page = page;
1521                                         frag->page_offset = 0;
1522                                         frag->size = (data_len >= PAGE_SIZE ?
1523                                                       PAGE_SIZE :
1524                                                       data_len);
1525                                         data_len -= PAGE_SIZE;
1526                                 }
1527
1528                                 /* Full success... */
1529                                 break;
1530                         }
1531                         err = -ENOBUFS;
1532                         goto failure;
1533                 }
1534                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1535                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1536                 err = -EAGAIN;
1537                 if (!timeo)
1538                         goto failure;
1539                 if (signal_pending(current))
1540                         goto interrupted;
1541                 timeo = sock_wait_for_wmem(sk, timeo);
1542         }
1543
1544         skb_set_owner_w(skb, sk);
1545         return skb;
1546
1547 interrupted:
1548         err = sock_intr_errno(timeo);
1549 failure:
1550         *errcode = err;
1551         return NULL;
1552 }
1553 EXPORT_SYMBOL(sock_alloc_send_pskb);
1554
1555 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1556                                     int noblock, int *errcode)
1557 {
1558         return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1559 }
1560 EXPORT_SYMBOL(sock_alloc_send_skb);
1561
1562 static void __lock_sock(struct sock *sk)
1563         __releases(&sk->sk_lock.slock)
1564         __acquires(&sk->sk_lock.slock)
1565 {
1566         DEFINE_WAIT(wait);
1567
1568         for (;;) {
1569                 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1570                                         TASK_UNINTERRUPTIBLE);
1571                 spin_unlock_bh(&sk->sk_lock.slock);
1572                 schedule();
1573                 spin_lock_bh(&sk->sk_lock.slock);
1574                 if (!sock_owned_by_user(sk))
1575                         break;
1576         }
1577         finish_wait(&sk->sk_lock.wq, &wait);
1578 }
1579
1580 static void __release_sock(struct sock *sk)
1581         __releases(&sk->sk_lock.slock)
1582         __acquires(&sk->sk_lock.slock)
1583 {
1584         struct sk_buff *skb = sk->sk_backlog.head;
1585
1586         do {
1587                 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1588                 bh_unlock_sock(sk);
1589
1590                 do {
1591                         struct sk_buff *next = skb->next;
1592
1593                         WARN_ON_ONCE(skb_dst_is_noref(skb));
1594                         skb->next = NULL;
1595                         sk_backlog_rcv(sk, skb);
1596
1597                         /*
1598                          * We are in process context here with softirqs
1599                          * disabled, use cond_resched_softirq() to preempt.
1600                          * This is safe to do because we've taken the backlog
1601                          * queue private:
1602                          */
1603                         cond_resched_softirq();
1604
1605                         skb = next;
1606                 } while (skb != NULL);
1607
1608                 bh_lock_sock(sk);
1609         } while ((skb = sk->sk_backlog.head) != NULL);
1610
1611         /*
1612          * Doing the zeroing here guarantee we can not loop forever
1613          * while a wild producer attempts to flood us.
1614          */
1615         sk->sk_backlog.len = 0;
1616 }
1617
1618 /**
1619  * sk_wait_data - wait for data to arrive at sk_receive_queue
1620  * @sk:    sock to wait on
1621  * @timeo: for how long
1622  *
1623  * Now socket state including sk->sk_err is changed only under lock,
1624  * hence we may omit checks after joining wait queue.
1625  * We check receive queue before schedule() only as optimization;
1626  * it is very likely that release_sock() added new data.
1627  */
1628 int sk_wait_data(struct sock *sk, long *timeo)
1629 {
1630         int rc;
1631         DEFINE_WAIT(wait);
1632
1633         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1634         set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1635         rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1636         clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1637         finish_wait(sk_sleep(sk), &wait);
1638         return rc;
1639 }
1640 EXPORT_SYMBOL(sk_wait_data);
1641
1642 /**
1643  *      __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1644  *      @sk: socket
1645  *      @size: memory size to allocate
1646  *      @kind: allocation type
1647  *
1648  *      If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1649  *      rmem allocation. This function assumes that protocols which have
1650  *      memory_pressure use sk_wmem_queued as write buffer accounting.
1651  */
1652 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1653 {
1654         struct proto *prot = sk->sk_prot;
1655         int amt = sk_mem_pages(size);
1656         int allocated;
1657
1658         sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1659         allocated = atomic_add_return(amt, prot->memory_allocated);
1660
1661         /* Under limit. */
1662         if (allocated <= prot->sysctl_mem[0]) {
1663                 if (prot->memory_pressure && *prot->memory_pressure)
1664                         *prot->memory_pressure = 0;
1665                 return 1;
1666         }
1667
1668         /* Under pressure. */
1669         if (allocated > prot->sysctl_mem[1])
1670                 if (prot->enter_memory_pressure)
1671                         prot->enter_memory_pressure(sk);
1672
1673         /* Over hard limit. */
1674         if (allocated > prot->sysctl_mem[2])
1675                 goto suppress_allocation;
1676
1677         /* guarantee minimum buffer size under pressure */
1678         if (kind == SK_MEM_RECV) {
1679                 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1680                         return 1;
1681         } else { /* SK_MEM_SEND */
1682                 if (sk->sk_type == SOCK_STREAM) {
1683                         if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1684                                 return 1;
1685                 } else if (atomic_read(&sk->sk_wmem_alloc) <
1686                            prot->sysctl_wmem[0])
1687                                 return 1;
1688         }
1689
1690         if (prot->memory_pressure) {
1691                 int alloc;
1692
1693                 if (!*prot->memory_pressure)
1694                         return 1;
1695                 alloc = percpu_counter_read_positive(prot->sockets_allocated);
1696                 if (prot->sysctl_mem[2] > alloc *
1697                     sk_mem_pages(sk->sk_wmem_queued +
1698                                  atomic_read(&sk->sk_rmem_alloc) +
1699                                  sk->sk_forward_alloc))
1700                         return 1;
1701         }
1702
1703 suppress_allocation:
1704
1705         if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1706                 sk_stream_moderate_sndbuf(sk);
1707
1708                 /* Fail only if socket is _under_ its sndbuf.
1709                  * In this case we cannot block, so that we have to fail.
1710                  */
1711                 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1712                         return 1;
1713         }
1714
1715         /* Alas. Undo changes. */
1716         sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1717         atomic_sub(amt, prot->memory_allocated);
1718         return 0;
1719 }
1720 EXPORT_SYMBOL(__sk_mem_schedule);
1721
1722 /**
1723  *      __sk_reclaim - reclaim memory_allocated
1724  *      @sk: socket
1725  */
1726 void __sk_mem_reclaim(struct sock *sk)
1727 {
1728         struct proto *prot = sk->sk_prot;
1729
1730         atomic_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1731                    prot->memory_allocated);
1732         sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1733
1734         if (prot->memory_pressure && *prot->memory_pressure &&
1735             (atomic_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1736                 *prot->memory_pressure = 0;
1737 }
1738 EXPORT_SYMBOL(__sk_mem_reclaim);
1739
1740
1741 /*
1742  * Set of default routines for initialising struct proto_ops when
1743  * the protocol does not support a particular function. In certain
1744  * cases where it makes no sense for a protocol to have a "do nothing"
1745  * function, some default processing is provided.
1746  */
1747
1748 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1749 {
1750         return -EOPNOTSUPP;
1751 }
1752 EXPORT_SYMBOL(sock_no_bind);
1753
1754 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1755                     int len, int flags)
1756 {
1757         return -EOPNOTSUPP;
1758 }
1759 EXPORT_SYMBOL(sock_no_connect);
1760
1761 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1762 {
1763         return -EOPNOTSUPP;
1764 }
1765 EXPORT_SYMBOL(sock_no_socketpair);
1766
1767 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1768 {
1769         return -EOPNOTSUPP;
1770 }
1771 EXPORT_SYMBOL(sock_no_accept);
1772
1773 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1774                     int *len, int peer)
1775 {
1776         return -EOPNOTSUPP;
1777 }
1778 EXPORT_SYMBOL(sock_no_getname);
1779
1780 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1781 {
1782         return 0;
1783 }
1784 EXPORT_SYMBOL(sock_no_poll);
1785
1786 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1787 {
1788         return -EOPNOTSUPP;
1789 }
1790 EXPORT_SYMBOL(sock_no_ioctl);
1791
1792 int sock_no_listen(struct socket *sock, int backlog)
1793 {
1794         return -EOPNOTSUPP;
1795 }
1796 EXPORT_SYMBOL(sock_no_listen);
1797
1798 int sock_no_shutdown(struct socket *sock, int how)
1799 {
1800         return -EOPNOTSUPP;
1801 }
1802 EXPORT_SYMBOL(sock_no_shutdown);
1803
1804 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1805                     char __user *optval, unsigned int optlen)
1806 {
1807         return -EOPNOTSUPP;
1808 }
1809 EXPORT_SYMBOL(sock_no_setsockopt);
1810
1811 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1812                     char __user *optval, int __user *optlen)
1813 {
1814         return -EOPNOTSUPP;
1815 }
1816 EXPORT_SYMBOL(sock_no_getsockopt);
1817
1818 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1819                     size_t len)
1820 {
1821         return -EOPNOTSUPP;
1822 }
1823 EXPORT_SYMBOL(sock_no_sendmsg);
1824
1825 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1826                     size_t len, int flags)
1827 {
1828         return -EOPNOTSUPP;
1829 }
1830 EXPORT_SYMBOL(sock_no_recvmsg);
1831
1832 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1833 {
1834         /* Mirror missing mmap method error code */
1835         return -ENODEV;
1836 }
1837 EXPORT_SYMBOL(sock_no_mmap);
1838
1839 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1840 {
1841         ssize_t res;
1842         struct msghdr msg = {.msg_flags = flags};
1843         struct kvec iov;
1844         char *kaddr = kmap(page);
1845         iov.iov_base = kaddr + offset;
1846         iov.iov_len = size;
1847         res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1848         kunmap(page);
1849         return res;
1850 }
1851 EXPORT_SYMBOL(sock_no_sendpage);
1852
1853 /*
1854  *      Default Socket Callbacks
1855  */
1856
1857 static void sock_def_wakeup(struct sock *sk)
1858 {
1859         struct socket_wq *wq;
1860
1861         rcu_read_lock();
1862         wq = rcu_dereference(sk->sk_wq);
1863         if (wq_has_sleeper(wq))
1864                 wake_up_interruptible_all(&wq->wait);
1865         rcu_read_unlock();
1866 }
1867
1868 static void sock_def_error_report(struct sock *sk)
1869 {
1870         struct socket_wq *wq;
1871
1872         rcu_read_lock();
1873         wq = rcu_dereference(sk->sk_wq);
1874         if (wq_has_sleeper(wq))
1875                 wake_up_interruptible_poll(&wq->wait, POLLERR);
1876         sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1877         rcu_read_unlock();
1878 }
1879
1880 static void sock_def_readable(struct sock *sk, int len)
1881 {
1882         struct socket_wq *wq;
1883
1884         rcu_read_lock();
1885         wq = rcu_dereference(sk->sk_wq);
1886         if (wq_has_sleeper(wq))
1887                 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
1888                                                 POLLRDNORM | POLLRDBAND);
1889         sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1890         rcu_read_unlock();
1891 }
1892
1893 static void sock_def_write_space(struct sock *sk)
1894 {
1895         struct socket_wq *wq;
1896
1897         rcu_read_lock();
1898
1899         /* Do not wake up a writer until he can make "significant"
1900          * progress.  --DaveM
1901          */
1902         if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1903                 wq = rcu_dereference(sk->sk_wq);
1904                 if (wq_has_sleeper(wq))
1905                         wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1906                                                 POLLWRNORM | POLLWRBAND);
1907
1908                 /* Should agree with poll, otherwise some programs break */
1909                 if (sock_writeable(sk))
1910                         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1911         }
1912
1913         rcu_read_unlock();
1914 }
1915
1916 static void sock_def_destruct(struct sock *sk)
1917 {
1918         kfree(sk->sk_protinfo);
1919 }
1920
1921 void sk_send_sigurg(struct sock *sk)
1922 {
1923         if (sk->sk_socket && sk->sk_socket->file)
1924                 if (send_sigurg(&sk->sk_socket->file->f_owner))
1925                         sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1926 }
1927 EXPORT_SYMBOL(sk_send_sigurg);
1928
1929 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1930                     unsigned long expires)
1931 {
1932         if (!mod_timer(timer, expires))
1933                 sock_hold(sk);
1934 }
1935 EXPORT_SYMBOL(sk_reset_timer);
1936
1937 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1938 {
1939         if (timer_pending(timer) && del_timer(timer))
1940                 __sock_put(sk);
1941 }
1942 EXPORT_SYMBOL(sk_stop_timer);
1943
1944 void sock_init_data(struct socket *sock, struct sock *sk)
1945 {
1946         skb_queue_head_init(&sk->sk_receive_queue);
1947         skb_queue_head_init(&sk->sk_write_queue);
1948         skb_queue_head_init(&sk->sk_error_queue);
1949 #ifdef CONFIG_NET_DMA
1950         skb_queue_head_init(&sk->sk_async_wait_queue);
1951 #endif
1952
1953         sk->sk_send_head        =       NULL;
1954
1955         init_timer(&sk->sk_timer);
1956
1957         sk->sk_allocation       =       GFP_KERNEL;
1958         sk->sk_rcvbuf           =       sysctl_rmem_default;
1959         sk->sk_sndbuf           =       sysctl_wmem_default;
1960         sk->sk_state            =       TCP_CLOSE;
1961         sk_set_socket(sk, sock);
1962
1963         sock_set_flag(sk, SOCK_ZAPPED);
1964
1965         if (sock) {
1966                 sk->sk_type     =       sock->type;
1967                 sk->sk_wq       =       sock->wq;
1968                 sock->sk        =       sk;
1969         } else
1970                 sk->sk_wq       =       NULL;
1971
1972         spin_lock_init(&sk->sk_dst_lock);
1973         rwlock_init(&sk->sk_callback_lock);
1974         lockdep_set_class_and_name(&sk->sk_callback_lock,
1975                         af_callback_keys + sk->sk_family,
1976                         af_family_clock_key_strings[sk->sk_family]);
1977
1978         sk->sk_state_change     =       sock_def_wakeup;
1979         sk->sk_data_ready       =       sock_def_readable;
1980         sk->sk_write_space      =       sock_def_write_space;
1981         sk->sk_error_report     =       sock_def_error_report;
1982         sk->sk_destruct         =       sock_def_destruct;
1983
1984         sk->sk_sndmsg_page      =       NULL;
1985         sk->sk_sndmsg_off       =       0;
1986
1987         sk->sk_peer_pid         =       NULL;
1988         sk->sk_peer_cred        =       NULL;
1989         sk->sk_write_pending    =       0;
1990         sk->sk_rcvlowat         =       1;
1991         sk->sk_rcvtimeo         =       MAX_SCHEDULE_TIMEOUT;
1992         sk->sk_sndtimeo         =       MAX_SCHEDULE_TIMEOUT;
1993
1994         sk->sk_stamp = ktime_set(-1L, 0);
1995
1996         /*
1997          * Before updating sk_refcnt, we must commit prior changes to memory
1998          * (Documentation/RCU/rculist_nulls.txt for details)
1999          */
2000         smp_wmb();
2001         atomic_set(&sk->sk_refcnt, 1);
2002         atomic_set(&sk->sk_drops, 0);
2003 }
2004 EXPORT_SYMBOL(sock_init_data);
2005
2006 void lock_sock_nested(struct sock *sk, int subclass)
2007 {
2008         might_sleep();
2009         spin_lock_bh(&sk->sk_lock.slock);
2010         if (sk->sk_lock.owned)
2011                 __lock_sock(sk);
2012         sk->sk_lock.owned = 1;
2013         spin_unlock(&sk->sk_lock.slock);
2014         /*
2015          * The sk_lock has mutex_lock() semantics here:
2016          */
2017         mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2018         local_bh_enable();
2019 }
2020 EXPORT_SYMBOL(lock_sock_nested);
2021
2022 void release_sock(struct sock *sk)
2023 {
2024         /*
2025          * The sk_lock has mutex_unlock() semantics:
2026          */
2027         mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2028
2029         spin_lock_bh(&sk->sk_lock.slock);
2030         if (sk->sk_backlog.tail)
2031                 __release_sock(sk);
2032         sk->sk_lock.owned = 0;
2033         if (waitqueue_active(&sk->sk_lock.wq))
2034                 wake_up(&sk->sk_lock.wq);
2035         spin_unlock_bh(&sk->sk_lock.slock);
2036 }
2037 EXPORT_SYMBOL(release_sock);
2038
2039 /**
2040  * lock_sock_fast - fast version of lock_sock
2041  * @sk: socket
2042  *
2043  * This version should be used for very small section, where process wont block
2044  * return false if fast path is taken
2045  *   sk_lock.slock locked, owned = 0, BH disabled
2046  * return true if slow path is taken
2047  *   sk_lock.slock unlocked, owned = 1, BH enabled
2048  */
2049 bool lock_sock_fast(struct sock *sk)
2050 {
2051         might_sleep();
2052         spin_lock_bh(&sk->sk_lock.slock);
2053
2054         if (!sk->sk_lock.owned)
2055                 /*
2056                  * Note : We must disable BH
2057                  */
2058                 return false;
2059
2060         __lock_sock(sk);
2061         sk->sk_lock.owned = 1;
2062         spin_unlock(&sk->sk_lock.slock);
2063         /*
2064          * The sk_lock has mutex_lock() semantics here:
2065          */
2066         mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2067         local_bh_enable();
2068         return true;
2069 }
2070 EXPORT_SYMBOL(lock_sock_fast);
2071
2072 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2073 {
2074         struct timeval tv;
2075         if (!sock_flag(sk, SOCK_TIMESTAMP))
2076                 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2077         tv = ktime_to_timeval(sk->sk_stamp);
2078         if (tv.tv_sec == -1)
2079                 return -ENOENT;
2080         if (tv.tv_sec == 0) {
2081                 sk->sk_stamp = ktime_get_real();
2082                 tv = ktime_to_timeval(sk->sk_stamp);
2083         }
2084         return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2085 }
2086 EXPORT_SYMBOL(sock_get_timestamp);
2087
2088 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2089 {
2090         struct timespec ts;
2091         if (!sock_flag(sk, SOCK_TIMESTAMP))
2092                 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2093         ts = ktime_to_timespec(sk->sk_stamp);
2094         if (ts.tv_sec == -1)
2095                 return -ENOENT;
2096         if (ts.tv_sec == 0) {
2097                 sk->sk_stamp = ktime_get_real();
2098                 ts = ktime_to_timespec(sk->sk_stamp);
2099         }
2100         return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2101 }
2102 EXPORT_SYMBOL(sock_get_timestampns);
2103
2104 void sock_enable_timestamp(struct sock *sk, int flag)
2105 {
2106         if (!sock_flag(sk, flag)) {
2107                 sock_set_flag(sk, flag);
2108                 /*
2109                  * we just set one of the two flags which require net
2110                  * time stamping, but time stamping might have been on
2111                  * already because of the other one
2112                  */
2113                 if (!sock_flag(sk,
2114                                 flag == SOCK_TIMESTAMP ?
2115                                 SOCK_TIMESTAMPING_RX_SOFTWARE :
2116                                 SOCK_TIMESTAMP))
2117                         net_enable_timestamp();
2118         }
2119 }
2120
2121 /*
2122  *      Get a socket option on an socket.
2123  *
2124  *      FIX: POSIX 1003.1g is very ambiguous here. It states that
2125  *      asynchronous errors should be reported by getsockopt. We assume
2126  *      this means if you specify SO_ERROR (otherwise whats the point of it).
2127  */
2128 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2129                            char __user *optval, int __user *optlen)
2130 {
2131         struct sock *sk = sock->sk;
2132
2133         return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2134 }
2135 EXPORT_SYMBOL(sock_common_getsockopt);
2136
2137 #ifdef CONFIG_COMPAT
2138 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2139                                   char __user *optval, int __user *optlen)
2140 {
2141         struct sock *sk = sock->sk;
2142
2143         if (sk->sk_prot->compat_getsockopt != NULL)
2144                 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2145                                                       optval, optlen);
2146         return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2147 }
2148 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2149 #endif
2150
2151 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2152                         struct msghdr *msg, size_t size, int flags)
2153 {
2154         struct sock *sk = sock->sk;
2155         int addr_len = 0;
2156         int err;
2157
2158         err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2159                                    flags & ~MSG_DONTWAIT, &addr_len);
2160         if (err >= 0)
2161                 msg->msg_namelen = addr_len;
2162         return err;
2163 }
2164 EXPORT_SYMBOL(sock_common_recvmsg);
2165
2166 /*
2167  *      Set socket options on an inet socket.
2168  */
2169 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2170                            char __user *optval, unsigned int optlen)
2171 {
2172         struct sock *sk = sock->sk;
2173
2174         return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2175 }
2176 EXPORT_SYMBOL(sock_common_setsockopt);
2177
2178 #ifdef CONFIG_COMPAT
2179 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2180                                   char __user *optval, unsigned int optlen)
2181 {
2182         struct sock *sk = sock->sk;
2183
2184         if (sk->sk_prot->compat_setsockopt != NULL)
2185                 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2186                                                       optval, optlen);
2187         return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2188 }
2189 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2190 #endif
2191
2192 void sk_common_release(struct sock *sk)
2193 {
2194         if (sk->sk_prot->destroy)
2195                 sk->sk_prot->destroy(sk);
2196
2197         /*
2198          * Observation: when sock_common_release is called, processes have
2199          * no access to socket. But net still has.
2200          * Step one, detach it from networking:
2201          *
2202          * A. Remove from hash tables.
2203          */
2204
2205         sk->sk_prot->unhash(sk);
2206
2207         /*
2208          * In this point socket cannot receive new packets, but it is possible
2209          * that some packets are in flight because some CPU runs receiver and
2210          * did hash table lookup before we unhashed socket. They will achieve
2211          * receive queue and will be purged by socket destructor.
2212          *
2213          * Also we still have packets pending on receive queue and probably,
2214          * our own packets waiting in device queues. sock_destroy will drain
2215          * receive queue, but transmitted packets will delay socket destruction
2216          * until the last reference will be released.
2217          */
2218
2219         sock_orphan(sk);
2220
2221         xfrm_sk_free_policy(sk);
2222
2223         sk_refcnt_debug_release(sk);
2224         sock_put(sk);
2225 }
2226 EXPORT_SYMBOL(sk_common_release);
2227
2228 static DEFINE_RWLOCK(proto_list_lock);
2229 static LIST_HEAD(proto_list);
2230
2231 #ifdef CONFIG_PROC_FS
2232 #define PROTO_INUSE_NR  64      /* should be enough for the first time */
2233 struct prot_inuse {
2234         int val[PROTO_INUSE_NR];
2235 };
2236
2237 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2238
2239 #ifdef CONFIG_NET_NS
2240 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2241 {
2242         __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2243 }
2244 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2245
2246 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2247 {
2248         int cpu, idx = prot->inuse_idx;
2249         int res = 0;
2250
2251         for_each_possible_cpu(cpu)
2252                 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2253
2254         return res >= 0 ? res : 0;
2255 }
2256 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2257
2258 static int __net_init sock_inuse_init_net(struct net *net)
2259 {
2260         net->core.inuse = alloc_percpu(struct prot_inuse);
2261         return net->core.inuse ? 0 : -ENOMEM;
2262 }
2263
2264 static void __net_exit sock_inuse_exit_net(struct net *net)
2265 {
2266         free_percpu(net->core.inuse);
2267 }
2268
2269 static struct pernet_operations net_inuse_ops = {
2270         .init = sock_inuse_init_net,
2271         .exit = sock_inuse_exit_net,
2272 };
2273
2274 static __init int net_inuse_init(void)
2275 {
2276         if (register_pernet_subsys(&net_inuse_ops))
2277                 panic("Cannot initialize net inuse counters");
2278
2279         return 0;
2280 }
2281
2282 core_initcall(net_inuse_init);
2283 #else
2284 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2285
2286 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2287 {
2288         __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2289 }
2290 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2291
2292 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2293 {
2294         int cpu, idx = prot->inuse_idx;
2295         int res = 0;
2296
2297         for_each_possible_cpu(cpu)
2298                 res += per_cpu(prot_inuse, cpu).val[idx];
2299
2300         return res >= 0 ? res : 0;
2301 }
2302 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2303 #endif
2304
2305 static void assign_proto_idx(struct proto *prot)
2306 {
2307         prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2308
2309         if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2310                 printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2311                 return;
2312         }
2313
2314         set_bit(prot->inuse_idx, proto_inuse_idx);
2315 }
2316
2317 static void release_proto_idx(struct proto *prot)
2318 {
2319         if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2320                 clear_bit(prot->inuse_idx, proto_inuse_idx);
2321 }
2322 #else
2323 static inline void assign_proto_idx(struct proto *prot)
2324 {
2325 }
2326
2327 static inline void release_proto_idx(struct proto *prot)
2328 {
2329 }
2330 #endif
2331
2332 int proto_register(struct proto *prot, int alloc_slab)
2333 {
2334         if (alloc_slab) {
2335                 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2336                                         SLAB_HWCACHE_ALIGN | prot->slab_flags,
2337                                         NULL);
2338
2339                 if (prot->slab == NULL) {
2340                         printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2341                                prot->name);
2342                         goto out;
2343                 }
2344
2345                 if (prot->rsk_prot != NULL) {
2346                         prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2347                         if (prot->rsk_prot->slab_name == NULL)
2348                                 goto out_free_sock_slab;
2349
2350                         prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2351                                                                  prot->rsk_prot->obj_size, 0,
2352                                                                  SLAB_HWCACHE_ALIGN, NULL);
2353
2354                         if (prot->rsk_prot->slab == NULL) {
2355                                 printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2356                                        prot->name);
2357                                 goto out_free_request_sock_slab_name;
2358                         }
2359                 }
2360
2361                 if (prot->twsk_prot != NULL) {
2362                         prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2363
2364                         if (prot->twsk_prot->twsk_slab_name == NULL)
2365                                 goto out_free_request_sock_slab;
2366
2367                         prot->twsk_prot->twsk_slab =
2368                                 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2369                                                   prot->twsk_prot->twsk_obj_size,
2370                                                   0,
2371                                                   SLAB_HWCACHE_ALIGN |
2372                                                         prot->slab_flags,
2373                                                   NULL);
2374                         if (prot->twsk_prot->twsk_slab == NULL)
2375                                 goto out_free_timewait_sock_slab_name;
2376                 }
2377         }
2378
2379         write_lock(&proto_list_lock);
2380         list_add(&prot->node, &proto_list);
2381         assign_proto_idx(prot);
2382         write_unlock(&proto_list_lock);
2383         return 0;
2384
2385 out_free_timewait_sock_slab_name:
2386         kfree(prot->twsk_prot->twsk_slab_name);
2387 out_free_request_sock_slab:
2388         if (prot->rsk_prot && prot->rsk_prot->slab) {
2389                 kmem_cache_destroy(prot->rsk_prot->slab);
2390                 prot->rsk_prot->slab = NULL;
2391         }
2392 out_free_request_sock_slab_name:
2393         if (prot->rsk_prot)
2394                 kfree(prot->rsk_prot->slab_name);
2395 out_free_sock_slab:
2396         kmem_cache_destroy(prot->slab);
2397         prot->slab = NULL;
2398 out:
2399         return -ENOBUFS;
2400 }
2401 EXPORT_SYMBOL(proto_register);
2402
2403 void proto_unregister(struct proto *prot)
2404 {
2405         write_lock(&proto_list_lock);
2406         release_proto_idx(prot);
2407         list_del(&prot->node);
2408         write_unlock(&proto_list_lock);
2409
2410         if (prot->slab != NULL) {
2411                 kmem_cache_destroy(prot->slab);
2412                 prot->slab = NULL;
2413         }
2414
2415         if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2416                 kmem_cache_destroy(prot->rsk_prot->slab);
2417                 kfree(prot->rsk_prot->slab_name);
2418                 prot->rsk_prot->slab = NULL;
2419         }
2420
2421         if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2422                 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2423                 kfree(prot->twsk_prot->twsk_slab_name);
2424                 prot->twsk_prot->twsk_slab = NULL;
2425         }
2426 }
2427 EXPORT_SYMBOL(proto_unregister);
2428
2429 #ifdef CONFIG_PROC_FS
2430 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2431         __acquires(proto_list_lock)
2432 {
2433         read_lock(&proto_list_lock);
2434         return seq_list_start_head(&proto_list, *pos);
2435 }
2436
2437 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2438 {
2439         return seq_list_next(v, &proto_list, pos);
2440 }
2441
2442 static void proto_seq_stop(struct seq_file *seq, void *v)
2443         __releases(proto_list_lock)
2444 {
2445         read_unlock(&proto_list_lock);
2446 }
2447
2448 static char proto_method_implemented(const void *method)
2449 {
2450         return method == NULL ? 'n' : 'y';
2451 }
2452
2453 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2454 {
2455         seq_printf(seq, "%-9s %4u %6d  %6d   %-3s %6u   %-3s  %-10s "
2456                         "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2457                    proto->name,
2458                    proto->obj_size,
2459                    sock_prot_inuse_get(seq_file_net(seq), proto),
2460                    proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
2461                    proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2462                    proto->max_header,
2463                    proto->slab == NULL ? "no" : "yes",
2464                    module_name(proto->owner),
2465                    proto_method_implemented(proto->close),
2466                    proto_method_implemented(proto->connect),
2467                    proto_method_implemented(proto->disconnect),
2468                    proto_method_implemented(proto->accept),
2469                    proto_method_implemented(proto->ioctl),
2470                    proto_method_implemented(proto->init),
2471                    proto_method_implemented(proto->destroy),
2472                    proto_method_implemented(proto->shutdown),
2473                    proto_method_implemented(proto->setsockopt),
2474                    proto_method_implemented(proto->getsockopt),
2475                    proto_method_implemented(proto->sendmsg),
2476                    proto_method_implemented(proto->recvmsg),
2477                    proto_method_implemented(proto->sendpage),
2478                    proto_method_implemented(proto->bind),
2479                    proto_method_implemented(proto->backlog_rcv),
2480                    proto_method_implemented(proto->hash),
2481                    proto_method_implemented(proto->unhash),
2482                    proto_method_implemented(proto->get_port),
2483                    proto_method_implemented(proto->enter_memory_pressure));
2484 }
2485
2486 static int proto_seq_show(struct seq_file *seq, void *v)
2487 {
2488         if (v == &proto_list)
2489                 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2490                            "protocol",
2491                            "size",
2492                            "sockets",
2493                            "memory",
2494                            "press",
2495                            "maxhdr",
2496                            "slab",
2497                            "module",
2498                            "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2499         else
2500                 proto_seq_printf(seq, list_entry(v, struct proto, node));
2501         return 0;
2502 }
2503
2504 static const struct seq_operations proto_seq_ops = {
2505         .start  = proto_seq_start,
2506         .next   = proto_seq_next,
2507         .stop   = proto_seq_stop,
2508         .show   = proto_seq_show,
2509 };
2510
2511 static int proto_seq_open(struct inode *inode, struct file *file)
2512 {
2513         return seq_open_net(inode, file, &proto_seq_ops,
2514                             sizeof(struct seq_net_private));
2515 }
2516
2517 static const struct file_operations proto_seq_fops = {
2518         .owner          = THIS_MODULE,
2519         .open           = proto_seq_open,
2520         .read           = seq_read,
2521         .llseek         = seq_lseek,
2522         .release        = seq_release_net,
2523 };
2524
2525 static __net_init int proto_init_net(struct net *net)
2526 {
2527         if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2528                 return -ENOMEM;
2529
2530         return 0;
2531 }
2532
2533 static __net_exit void proto_exit_net(struct net *net)
2534 {
2535         proc_net_remove(net, "protocols");
2536 }
2537
2538
2539 static __net_initdata struct pernet_operations proto_net_ops = {
2540         .init = proto_init_net,
2541         .exit = proto_exit_net,
2542 };
2543
2544 static int __init proto_init(void)
2545 {
2546         return register_pernet_subsys(&proto_net_ops);
2547 }
2548
2549 subsys_initcall(proto_init);
2550
2551 #endif /* PROC_FS */