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