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lib: lz4: cleanup unaligned access efficiency detection
[deliverable/linux.git] / net / core / sock.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
8 *
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 * Alan Cox : Numerous verify_area() problems
17 * Alan Cox : Connecting on a connecting socket
18 * now returns an error for tcp.
19 * Alan Cox : sock->protocol is set correctly.
20 * and is not sometimes left as 0.
21 * Alan Cox : connect handles icmp errors on a
22 * connect properly. Unfortunately there
23 * is a restart syscall nasty there. I
24 * can't match BSD without hacking the C
25 * library. Ideas urgently sought!
26 * Alan Cox : Disallow bind() to addresses that are
27 * not ours - especially broadcast ones!!
28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
30 * instead they leave that for the DESTROY timer.
31 * Alan Cox : Clean up error flag in accept
32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer
33 * was buggy. Put a remove_sock() in the handler
34 * for memory when we hit 0. Also altered the timer
35 * code. The ACK stuff can wait and needs major
36 * TCP layer surgery.
37 * Alan Cox : Fixed TCP ack bug, removed remove sock
38 * and fixed timer/inet_bh race.
39 * Alan Cox : Added zapped flag for TCP
40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 * Rick Sladkey : Relaxed UDP rules for matching packets.
46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
47 * Pauline Middelink : identd support
48 * Alan Cox : Fixed connect() taking signals I think.
49 * Alan Cox : SO_LINGER supported
50 * Alan Cox : Error reporting fixes
51 * Anonymous : inet_create tidied up (sk->reuse setting)
52 * Alan Cox : inet sockets don't set sk->type!
53 * Alan Cox : Split socket option code
54 * Alan Cox : Callbacks
55 * Alan Cox : Nagle flag for Charles & Johannes stuff
56 * Alex : Removed restriction on inet fioctl
57 * Alan Cox : Splitting INET from NET core
58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
60 * Alan Cox : Split IP from generic code
61 * Alan Cox : New kfree_skbmem()
62 * Alan Cox : Make SO_DEBUG superuser only.
63 * Alan Cox : Allow anyone to clear SO_DEBUG
64 * (compatibility fix)
65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
66 * Alan Cox : Allocator for a socket is settable.
67 * Alan Cox : SO_ERROR includes soft errors.
68 * Alan Cox : Allow NULL arguments on some SO_ opts
69 * Alan Cox : Generic socket allocation to make hooks
70 * easier (suggested by Craig Metz).
71 * Michael Pall : SO_ERROR returns positive errno again
72 * Steve Whitehouse: Added default destructor to free
73 * protocol private data.
74 * Steve Whitehouse: Added various other default routines
75 * common to several socket families.
76 * Chris Evans : Call suser() check last on F_SETOWN
77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
79 * Andi Kleen : Fix write_space callback
80 * Chris Evans : Security fixes - signedness again
81 * Arnaldo C. Melo : cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 * This program is free software; you can redistribute it and/or
87 * modify it under the terms of the GNU General Public License
88 * as published by the Free Software Foundation; either version
89 * 2 of the License, or (at your option) any later version.
90 */
91
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/errqueue.h>
97 #include <linux/types.h>
98 #include <linux/socket.h>
99 #include <linux/in.h>
100 #include <linux/kernel.h>
101 #include <linux/module.h>
102 #include <linux/proc_fs.h>
103 #include <linux/seq_file.h>
104 #include <linux/sched.h>
105 #include <linux/timer.h>
106 #include <linux/string.h>
107 #include <linux/sockios.h>
108 #include <linux/net.h>
109 #include <linux/mm.h>
110 #include <linux/slab.h>
111 #include <linux/interrupt.h>
112 #include <linux/poll.h>
113 #include <linux/tcp.h>
114 #include <linux/init.h>
115 #include <linux/highmem.h>
116 #include <linux/user_namespace.h>
117 #include <linux/static_key.h>
118 #include <linux/memcontrol.h>
119 #include <linux/prefetch.h>
120
121 #include <asm/uaccess.h>
122
123 #include <linux/netdevice.h>
124 #include <net/protocol.h>
125 #include <linux/skbuff.h>
126 #include <net/net_namespace.h>
127 #include <net/request_sock.h>
128 #include <net/sock.h>
129 #include <linux/net_tstamp.h>
130 #include <net/xfrm.h>
131 #include <linux/ipsec.h>
132 #include <net/cls_cgroup.h>
133 #include <net/netprio_cgroup.h>
134 #include <linux/sock_diag.h>
135
136 #include <linux/filter.h>
137 #include <net/sock_reuseport.h>
138
139 #include <trace/events/sock.h>
140
141 #ifdef CONFIG_INET
142 #include <net/tcp.h>
143 #endif
144
145 #include <net/busy_poll.h>
146
147 static DEFINE_MUTEX(proto_list_mutex);
148 static LIST_HEAD(proto_list);
149
150 /**
151 * sk_ns_capable - General socket capability test
152 * @sk: Socket to use a capability on or through
153 * @user_ns: The user namespace of the capability to use
154 * @cap: The capability to use
155 *
156 * Test to see if the opener of the socket had when the socket was
157 * created and the current process has the capability @cap in the user
158 * namespace @user_ns.
159 */
160 bool sk_ns_capable(const struct sock *sk,
161 struct user_namespace *user_ns, int cap)
162 {
163 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
164 ns_capable(user_ns, cap);
165 }
166 EXPORT_SYMBOL(sk_ns_capable);
167
168 /**
169 * sk_capable - Socket global capability test
170 * @sk: Socket to use a capability on or through
171 * @cap: The global capability to use
172 *
173 * Test to see if the opener of the socket had when the socket was
174 * created and the current process has the capability @cap in all user
175 * namespaces.
176 */
177 bool sk_capable(const struct sock *sk, int cap)
178 {
179 return sk_ns_capable(sk, &init_user_ns, cap);
180 }
181 EXPORT_SYMBOL(sk_capable);
182
183 /**
184 * sk_net_capable - Network namespace socket capability test
185 * @sk: Socket to use a capability on or through
186 * @cap: The capability to use
187 *
188 * Test to see if the opener of the socket had when the socket was created
189 * and the current process has the capability @cap over the network namespace
190 * the socket is a member of.
191 */
192 bool sk_net_capable(const struct sock *sk, int cap)
193 {
194 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
195 }
196 EXPORT_SYMBOL(sk_net_capable);
197
198 /*
199 * Each address family might have different locking rules, so we have
200 * one slock key per address family:
201 */
202 static struct lock_class_key af_family_keys[AF_MAX];
203 static struct lock_class_key af_family_slock_keys[AF_MAX];
204
205 /*
206 * Make lock validator output more readable. (we pre-construct these
207 * strings build-time, so that runtime initialization of socket
208 * locks is fast):
209 */
210 static const char *const af_family_key_strings[AF_MAX+1] = {
211 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
212 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
213 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
214 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
215 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
216 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
217 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
218 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
219 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
220 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
221 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
222 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
223 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
224 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
225 };
226 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
227 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
228 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
229 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
230 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
231 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
232 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
233 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
234 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
235 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
236 "slock-27" , "slock-28" , "slock-AF_CAN" ,
237 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
238 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
239 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
240 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
241 };
242 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
243 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
244 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
245 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
246 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
247 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
248 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
249 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
250 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
251 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
252 "clock-27" , "clock-28" , "clock-AF_CAN" ,
253 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
254 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
255 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
256 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
257 };
258
259 /*
260 * sk_callback_lock locking rules are per-address-family,
261 * so split the lock classes by using a per-AF key:
262 */
263 static struct lock_class_key af_callback_keys[AF_MAX];
264
265 /* Take into consideration the size of the struct sk_buff overhead in the
266 * determination of these values, since that is non-constant across
267 * platforms. This makes socket queueing behavior and performance
268 * not depend upon such differences.
269 */
270 #define _SK_MEM_PACKETS 256
271 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
272 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
273 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
274
275 /* Run time adjustable parameters. */
276 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
277 EXPORT_SYMBOL(sysctl_wmem_max);
278 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
279 EXPORT_SYMBOL(sysctl_rmem_max);
280 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
281 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
282
283 /* Maximal space eaten by iovec or ancillary data plus some space */
284 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
285 EXPORT_SYMBOL(sysctl_optmem_max);
286
287 int sysctl_tstamp_allow_data __read_mostly = 1;
288
289 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
290 EXPORT_SYMBOL_GPL(memalloc_socks);
291
292 /**
293 * sk_set_memalloc - sets %SOCK_MEMALLOC
294 * @sk: socket to set it on
295 *
296 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
297 * It's the responsibility of the admin to adjust min_free_kbytes
298 * to meet the requirements
299 */
300 void sk_set_memalloc(struct sock *sk)
301 {
302 sock_set_flag(sk, SOCK_MEMALLOC);
303 sk->sk_allocation |= __GFP_MEMALLOC;
304 static_key_slow_inc(&memalloc_socks);
305 }
306 EXPORT_SYMBOL_GPL(sk_set_memalloc);
307
308 void sk_clear_memalloc(struct sock *sk)
309 {
310 sock_reset_flag(sk, SOCK_MEMALLOC);
311 sk->sk_allocation &= ~__GFP_MEMALLOC;
312 static_key_slow_dec(&memalloc_socks);
313
314 /*
315 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
316 * progress of swapping. SOCK_MEMALLOC may be cleared while
317 * it has rmem allocations due to the last swapfile being deactivated
318 * but there is a risk that the socket is unusable due to exceeding
319 * the rmem limits. Reclaim the reserves and obey rmem limits again.
320 */
321 sk_mem_reclaim(sk);
322 }
323 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
324
325 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
326 {
327 int ret;
328 unsigned long pflags = current->flags;
329
330 /* these should have been dropped before queueing */
331 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
332
333 current->flags |= PF_MEMALLOC;
334 ret = sk->sk_backlog_rcv(sk, skb);
335 tsk_restore_flags(current, pflags, PF_MEMALLOC);
336
337 return ret;
338 }
339 EXPORT_SYMBOL(__sk_backlog_rcv);
340
341 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
342 {
343 struct timeval tv;
344
345 if (optlen < sizeof(tv))
346 return -EINVAL;
347 if (copy_from_user(&tv, optval, sizeof(tv)))
348 return -EFAULT;
349 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
350 return -EDOM;
351
352 if (tv.tv_sec < 0) {
353 static int warned __read_mostly;
354
355 *timeo_p = 0;
356 if (warned < 10 && net_ratelimit()) {
357 warned++;
358 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
359 __func__, current->comm, task_pid_nr(current));
360 }
361 return 0;
362 }
363 *timeo_p = MAX_SCHEDULE_TIMEOUT;
364 if (tv.tv_sec == 0 && tv.tv_usec == 0)
365 return 0;
366 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
367 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
368 return 0;
369 }
370
371 static void sock_warn_obsolete_bsdism(const char *name)
372 {
373 static int warned;
374 static char warncomm[TASK_COMM_LEN];
375 if (strcmp(warncomm, current->comm) && warned < 5) {
376 strcpy(warncomm, current->comm);
377 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
378 warncomm, name);
379 warned++;
380 }
381 }
382
383 static bool sock_needs_netstamp(const struct sock *sk)
384 {
385 switch (sk->sk_family) {
386 case AF_UNSPEC:
387 case AF_UNIX:
388 return false;
389 default:
390 return true;
391 }
392 }
393
394 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
395 {
396 if (sk->sk_flags & flags) {
397 sk->sk_flags &= ~flags;
398 if (sock_needs_netstamp(sk) &&
399 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
400 net_disable_timestamp();
401 }
402 }
403
404
405 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
406 {
407 int err;
408 unsigned long flags;
409 struct sk_buff_head *list = &sk->sk_receive_queue;
410
411 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
412 atomic_inc(&sk->sk_drops);
413 trace_sock_rcvqueue_full(sk, skb);
414 return -ENOMEM;
415 }
416
417 err = sk_filter(sk, skb);
418 if (err)
419 return err;
420
421 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
422 atomic_inc(&sk->sk_drops);
423 return -ENOBUFS;
424 }
425
426 skb->dev = NULL;
427 skb_set_owner_r(skb, sk);
428
429 /* we escape from rcu protected region, make sure we dont leak
430 * a norefcounted dst
431 */
432 skb_dst_force(skb);
433
434 spin_lock_irqsave(&list->lock, flags);
435 sock_skb_set_dropcount(sk, skb);
436 __skb_queue_tail(list, skb);
437 spin_unlock_irqrestore(&list->lock, flags);
438
439 if (!sock_flag(sk, SOCK_DEAD))
440 sk->sk_data_ready(sk);
441 return 0;
442 }
443 EXPORT_SYMBOL(sock_queue_rcv_skb);
444
445 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
446 {
447 int rc = NET_RX_SUCCESS;
448
449 if (sk_filter(sk, skb))
450 goto discard_and_relse;
451
452 skb->dev = NULL;
453
454 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
455 atomic_inc(&sk->sk_drops);
456 goto discard_and_relse;
457 }
458 if (nested)
459 bh_lock_sock_nested(sk);
460 else
461 bh_lock_sock(sk);
462 if (!sock_owned_by_user(sk)) {
463 /*
464 * trylock + unlock semantics:
465 */
466 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
467
468 rc = sk_backlog_rcv(sk, skb);
469
470 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
471 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
472 bh_unlock_sock(sk);
473 atomic_inc(&sk->sk_drops);
474 goto discard_and_relse;
475 }
476
477 bh_unlock_sock(sk);
478 out:
479 sock_put(sk);
480 return rc;
481 discard_and_relse:
482 kfree_skb(skb);
483 goto out;
484 }
485 EXPORT_SYMBOL(sk_receive_skb);
486
487 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
488 {
489 struct dst_entry *dst = __sk_dst_get(sk);
490
491 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
492 sk_tx_queue_clear(sk);
493 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
494 dst_release(dst);
495 return NULL;
496 }
497
498 return dst;
499 }
500 EXPORT_SYMBOL(__sk_dst_check);
501
502 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
503 {
504 struct dst_entry *dst = sk_dst_get(sk);
505
506 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
507 sk_dst_reset(sk);
508 dst_release(dst);
509 return NULL;
510 }
511
512 return dst;
513 }
514 EXPORT_SYMBOL(sk_dst_check);
515
516 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
517 int optlen)
518 {
519 int ret = -ENOPROTOOPT;
520 #ifdef CONFIG_NETDEVICES
521 struct net *net = sock_net(sk);
522 char devname[IFNAMSIZ];
523 int index;
524
525 /* Sorry... */
526 ret = -EPERM;
527 if (!ns_capable(net->user_ns, CAP_NET_RAW))
528 goto out;
529
530 ret = -EINVAL;
531 if (optlen < 0)
532 goto out;
533
534 /* Bind this socket to a particular device like "eth0",
535 * as specified in the passed interface name. If the
536 * name is "" or the option length is zero the socket
537 * is not bound.
538 */
539 if (optlen > IFNAMSIZ - 1)
540 optlen = IFNAMSIZ - 1;
541 memset(devname, 0, sizeof(devname));
542
543 ret = -EFAULT;
544 if (copy_from_user(devname, optval, optlen))
545 goto out;
546
547 index = 0;
548 if (devname[0] != '\0') {
549 struct net_device *dev;
550
551 rcu_read_lock();
552 dev = dev_get_by_name_rcu(net, devname);
553 if (dev)
554 index = dev->ifindex;
555 rcu_read_unlock();
556 ret = -ENODEV;
557 if (!dev)
558 goto out;
559 }
560
561 lock_sock(sk);
562 sk->sk_bound_dev_if = index;
563 sk_dst_reset(sk);
564 release_sock(sk);
565
566 ret = 0;
567
568 out:
569 #endif
570
571 return ret;
572 }
573
574 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
575 int __user *optlen, int len)
576 {
577 int ret = -ENOPROTOOPT;
578 #ifdef CONFIG_NETDEVICES
579 struct net *net = sock_net(sk);
580 char devname[IFNAMSIZ];
581
582 if (sk->sk_bound_dev_if == 0) {
583 len = 0;
584 goto zero;
585 }
586
587 ret = -EINVAL;
588 if (len < IFNAMSIZ)
589 goto out;
590
591 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
592 if (ret)
593 goto out;
594
595 len = strlen(devname) + 1;
596
597 ret = -EFAULT;
598 if (copy_to_user(optval, devname, len))
599 goto out;
600
601 zero:
602 ret = -EFAULT;
603 if (put_user(len, optlen))
604 goto out;
605
606 ret = 0;
607
608 out:
609 #endif
610
611 return ret;
612 }
613
614 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
615 {
616 if (valbool)
617 sock_set_flag(sk, bit);
618 else
619 sock_reset_flag(sk, bit);
620 }
621
622 bool sk_mc_loop(struct sock *sk)
623 {
624 if (dev_recursion_level())
625 return false;
626 if (!sk)
627 return true;
628 switch (sk->sk_family) {
629 case AF_INET:
630 return inet_sk(sk)->mc_loop;
631 #if IS_ENABLED(CONFIG_IPV6)
632 case AF_INET6:
633 return inet6_sk(sk)->mc_loop;
634 #endif
635 }
636 WARN_ON(1);
637 return true;
638 }
639 EXPORT_SYMBOL(sk_mc_loop);
640
641 /*
642 * This is meant for all protocols to use and covers goings on
643 * at the socket level. Everything here is generic.
644 */
645
646 int sock_setsockopt(struct socket *sock, int level, int optname,
647 char __user *optval, unsigned int optlen)
648 {
649 struct sock *sk = sock->sk;
650 int val;
651 int valbool;
652 struct linger ling;
653 int ret = 0;
654
655 /*
656 * Options without arguments
657 */
658
659 if (optname == SO_BINDTODEVICE)
660 return sock_setbindtodevice(sk, optval, optlen);
661
662 if (optlen < sizeof(int))
663 return -EINVAL;
664
665 if (get_user(val, (int __user *)optval))
666 return -EFAULT;
667
668 valbool = val ? 1 : 0;
669
670 lock_sock(sk);
671
672 switch (optname) {
673 case SO_DEBUG:
674 if (val && !capable(CAP_NET_ADMIN))
675 ret = -EACCES;
676 else
677 sock_valbool_flag(sk, SOCK_DBG, valbool);
678 break;
679 case SO_REUSEADDR:
680 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
681 break;
682 case SO_REUSEPORT:
683 sk->sk_reuseport = valbool;
684 break;
685 case SO_TYPE:
686 case SO_PROTOCOL:
687 case SO_DOMAIN:
688 case SO_ERROR:
689 ret = -ENOPROTOOPT;
690 break;
691 case SO_DONTROUTE:
692 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
693 break;
694 case SO_BROADCAST:
695 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
696 break;
697 case SO_SNDBUF:
698 /* Don't error on this BSD doesn't and if you think
699 * about it this is right. Otherwise apps have to
700 * play 'guess the biggest size' games. RCVBUF/SNDBUF
701 * are treated in BSD as hints
702 */
703 val = min_t(u32, val, sysctl_wmem_max);
704 set_sndbuf:
705 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
706 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
707 /* Wake up sending tasks if we upped the value. */
708 sk->sk_write_space(sk);
709 break;
710
711 case SO_SNDBUFFORCE:
712 if (!capable(CAP_NET_ADMIN)) {
713 ret = -EPERM;
714 break;
715 }
716 goto set_sndbuf;
717
718 case SO_RCVBUF:
719 /* Don't error on this BSD doesn't and if you think
720 * about it this is right. Otherwise apps have to
721 * play 'guess the biggest size' games. RCVBUF/SNDBUF
722 * are treated in BSD as hints
723 */
724 val = min_t(u32, val, sysctl_rmem_max);
725 set_rcvbuf:
726 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
727 /*
728 * We double it on the way in to account for
729 * "struct sk_buff" etc. overhead. Applications
730 * assume that the SO_RCVBUF setting they make will
731 * allow that much actual data to be received on that
732 * socket.
733 *
734 * Applications are unaware that "struct sk_buff" and
735 * other overheads allocate from the receive buffer
736 * during socket buffer allocation.
737 *
738 * And after considering the possible alternatives,
739 * returning the value we actually used in getsockopt
740 * is the most desirable behavior.
741 */
742 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
743 break;
744
745 case SO_RCVBUFFORCE:
746 if (!capable(CAP_NET_ADMIN)) {
747 ret = -EPERM;
748 break;
749 }
750 goto set_rcvbuf;
751
752 case SO_KEEPALIVE:
753 #ifdef CONFIG_INET
754 if (sk->sk_protocol == IPPROTO_TCP &&
755 sk->sk_type == SOCK_STREAM)
756 tcp_set_keepalive(sk, valbool);
757 #endif
758 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
759 break;
760
761 case SO_OOBINLINE:
762 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
763 break;
764
765 case SO_NO_CHECK:
766 sk->sk_no_check_tx = valbool;
767 break;
768
769 case SO_PRIORITY:
770 if ((val >= 0 && val <= 6) ||
771 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
772 sk->sk_priority = val;
773 else
774 ret = -EPERM;
775 break;
776
777 case SO_LINGER:
778 if (optlen < sizeof(ling)) {
779 ret = -EINVAL; /* 1003.1g */
780 break;
781 }
782 if (copy_from_user(&ling, optval, sizeof(ling))) {
783 ret = -EFAULT;
784 break;
785 }
786 if (!ling.l_onoff)
787 sock_reset_flag(sk, SOCK_LINGER);
788 else {
789 #if (BITS_PER_LONG == 32)
790 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
791 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
792 else
793 #endif
794 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
795 sock_set_flag(sk, SOCK_LINGER);
796 }
797 break;
798
799 case SO_BSDCOMPAT:
800 sock_warn_obsolete_bsdism("setsockopt");
801 break;
802
803 case SO_PASSCRED:
804 if (valbool)
805 set_bit(SOCK_PASSCRED, &sock->flags);
806 else
807 clear_bit(SOCK_PASSCRED, &sock->flags);
808 break;
809
810 case SO_TIMESTAMP:
811 case SO_TIMESTAMPNS:
812 if (valbool) {
813 if (optname == SO_TIMESTAMP)
814 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
815 else
816 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
817 sock_set_flag(sk, SOCK_RCVTSTAMP);
818 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
819 } else {
820 sock_reset_flag(sk, SOCK_RCVTSTAMP);
821 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
822 }
823 break;
824
825 case SO_TIMESTAMPING:
826 if (val & ~SOF_TIMESTAMPING_MASK) {
827 ret = -EINVAL;
828 break;
829 }
830
831 if (val & SOF_TIMESTAMPING_OPT_ID &&
832 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
833 if (sk->sk_protocol == IPPROTO_TCP &&
834 sk->sk_type == SOCK_STREAM) {
835 if (sk->sk_state != TCP_ESTABLISHED) {
836 ret = -EINVAL;
837 break;
838 }
839 sk->sk_tskey = tcp_sk(sk)->snd_una;
840 } else {
841 sk->sk_tskey = 0;
842 }
843 }
844 sk->sk_tsflags = val;
845 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
846 sock_enable_timestamp(sk,
847 SOCK_TIMESTAMPING_RX_SOFTWARE);
848 else
849 sock_disable_timestamp(sk,
850 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
851 break;
852
853 case SO_RCVLOWAT:
854 if (val < 0)
855 val = INT_MAX;
856 sk->sk_rcvlowat = val ? : 1;
857 break;
858
859 case SO_RCVTIMEO:
860 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
861 break;
862
863 case SO_SNDTIMEO:
864 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
865 break;
866
867 case SO_ATTACH_FILTER:
868 ret = -EINVAL;
869 if (optlen == sizeof(struct sock_fprog)) {
870 struct sock_fprog fprog;
871
872 ret = -EFAULT;
873 if (copy_from_user(&fprog, optval, sizeof(fprog)))
874 break;
875
876 ret = sk_attach_filter(&fprog, sk);
877 }
878 break;
879
880 case SO_ATTACH_BPF:
881 ret = -EINVAL;
882 if (optlen == sizeof(u32)) {
883 u32 ufd;
884
885 ret = -EFAULT;
886 if (copy_from_user(&ufd, optval, sizeof(ufd)))
887 break;
888
889 ret = sk_attach_bpf(ufd, sk);
890 }
891 break;
892
893 case SO_ATTACH_REUSEPORT_CBPF:
894 ret = -EINVAL;
895 if (optlen == sizeof(struct sock_fprog)) {
896 struct sock_fprog fprog;
897
898 ret = -EFAULT;
899 if (copy_from_user(&fprog, optval, sizeof(fprog)))
900 break;
901
902 ret = sk_reuseport_attach_filter(&fprog, sk);
903 }
904 break;
905
906 case SO_ATTACH_REUSEPORT_EBPF:
907 ret = -EINVAL;
908 if (optlen == sizeof(u32)) {
909 u32 ufd;
910
911 ret = -EFAULT;
912 if (copy_from_user(&ufd, optval, sizeof(ufd)))
913 break;
914
915 ret = sk_reuseport_attach_bpf(ufd, sk);
916 }
917 break;
918
919 case SO_DETACH_FILTER:
920 ret = sk_detach_filter(sk);
921 break;
922
923 case SO_LOCK_FILTER:
924 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
925 ret = -EPERM;
926 else
927 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
928 break;
929
930 case SO_PASSSEC:
931 if (valbool)
932 set_bit(SOCK_PASSSEC, &sock->flags);
933 else
934 clear_bit(SOCK_PASSSEC, &sock->flags);
935 break;
936 case SO_MARK:
937 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
938 ret = -EPERM;
939 else
940 sk->sk_mark = val;
941 break;
942
943 case SO_RXQ_OVFL:
944 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
945 break;
946
947 case SO_WIFI_STATUS:
948 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
949 break;
950
951 case SO_PEEK_OFF:
952 if (sock->ops->set_peek_off)
953 ret = sock->ops->set_peek_off(sk, val);
954 else
955 ret = -EOPNOTSUPP;
956 break;
957
958 case SO_NOFCS:
959 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
960 break;
961
962 case SO_SELECT_ERR_QUEUE:
963 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
964 break;
965
966 #ifdef CONFIG_NET_RX_BUSY_POLL
967 case SO_BUSY_POLL:
968 /* allow unprivileged users to decrease the value */
969 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
970 ret = -EPERM;
971 else {
972 if (val < 0)
973 ret = -EINVAL;
974 else
975 sk->sk_ll_usec = val;
976 }
977 break;
978 #endif
979
980 case SO_MAX_PACING_RATE:
981 sk->sk_max_pacing_rate = val;
982 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
983 sk->sk_max_pacing_rate);
984 break;
985
986 case SO_INCOMING_CPU:
987 sk->sk_incoming_cpu = val;
988 break;
989
990 case SO_CNX_ADVICE:
991 if (val == 1)
992 dst_negative_advice(sk);
993 break;
994 default:
995 ret = -ENOPROTOOPT;
996 break;
997 }
998 release_sock(sk);
999 return ret;
1000 }
1001 EXPORT_SYMBOL(sock_setsockopt);
1002
1003
1004 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1005 struct ucred *ucred)
1006 {
1007 ucred->pid = pid_vnr(pid);
1008 ucred->uid = ucred->gid = -1;
1009 if (cred) {
1010 struct user_namespace *current_ns = current_user_ns();
1011
1012 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1013 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1014 }
1015 }
1016
1017 int sock_getsockopt(struct socket *sock, int level, int optname,
1018 char __user *optval, int __user *optlen)
1019 {
1020 struct sock *sk = sock->sk;
1021
1022 union {
1023 int val;
1024 struct linger ling;
1025 struct timeval tm;
1026 } v;
1027
1028 int lv = sizeof(int);
1029 int len;
1030
1031 if (get_user(len, optlen))
1032 return -EFAULT;
1033 if (len < 0)
1034 return -EINVAL;
1035
1036 memset(&v, 0, sizeof(v));
1037
1038 switch (optname) {
1039 case SO_DEBUG:
1040 v.val = sock_flag(sk, SOCK_DBG);
1041 break;
1042
1043 case SO_DONTROUTE:
1044 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1045 break;
1046
1047 case SO_BROADCAST:
1048 v.val = sock_flag(sk, SOCK_BROADCAST);
1049 break;
1050
1051 case SO_SNDBUF:
1052 v.val = sk->sk_sndbuf;
1053 break;
1054
1055 case SO_RCVBUF:
1056 v.val = sk->sk_rcvbuf;
1057 break;
1058
1059 case SO_REUSEADDR:
1060 v.val = sk->sk_reuse;
1061 break;
1062
1063 case SO_REUSEPORT:
1064 v.val = sk->sk_reuseport;
1065 break;
1066
1067 case SO_KEEPALIVE:
1068 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1069 break;
1070
1071 case SO_TYPE:
1072 v.val = sk->sk_type;
1073 break;
1074
1075 case SO_PROTOCOL:
1076 v.val = sk->sk_protocol;
1077 break;
1078
1079 case SO_DOMAIN:
1080 v.val = sk->sk_family;
1081 break;
1082
1083 case SO_ERROR:
1084 v.val = -sock_error(sk);
1085 if (v.val == 0)
1086 v.val = xchg(&sk->sk_err_soft, 0);
1087 break;
1088
1089 case SO_OOBINLINE:
1090 v.val = sock_flag(sk, SOCK_URGINLINE);
1091 break;
1092
1093 case SO_NO_CHECK:
1094 v.val = sk->sk_no_check_tx;
1095 break;
1096
1097 case SO_PRIORITY:
1098 v.val = sk->sk_priority;
1099 break;
1100
1101 case SO_LINGER:
1102 lv = sizeof(v.ling);
1103 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1104 v.ling.l_linger = sk->sk_lingertime / HZ;
1105 break;
1106
1107 case SO_BSDCOMPAT:
1108 sock_warn_obsolete_bsdism("getsockopt");
1109 break;
1110
1111 case SO_TIMESTAMP:
1112 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1113 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1114 break;
1115
1116 case SO_TIMESTAMPNS:
1117 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1118 break;
1119
1120 case SO_TIMESTAMPING:
1121 v.val = sk->sk_tsflags;
1122 break;
1123
1124 case SO_RCVTIMEO:
1125 lv = sizeof(struct timeval);
1126 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1127 v.tm.tv_sec = 0;
1128 v.tm.tv_usec = 0;
1129 } else {
1130 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1131 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1132 }
1133 break;
1134
1135 case SO_SNDTIMEO:
1136 lv = sizeof(struct timeval);
1137 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1138 v.tm.tv_sec = 0;
1139 v.tm.tv_usec = 0;
1140 } else {
1141 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1142 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1143 }
1144 break;
1145
1146 case SO_RCVLOWAT:
1147 v.val = sk->sk_rcvlowat;
1148 break;
1149
1150 case SO_SNDLOWAT:
1151 v.val = 1;
1152 break;
1153
1154 case SO_PASSCRED:
1155 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1156 break;
1157
1158 case SO_PEERCRED:
1159 {
1160 struct ucred peercred;
1161 if (len > sizeof(peercred))
1162 len = sizeof(peercred);
1163 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1164 if (copy_to_user(optval, &peercred, len))
1165 return -EFAULT;
1166 goto lenout;
1167 }
1168
1169 case SO_PEERNAME:
1170 {
1171 char address[128];
1172
1173 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1174 return -ENOTCONN;
1175 if (lv < len)
1176 return -EINVAL;
1177 if (copy_to_user(optval, address, len))
1178 return -EFAULT;
1179 goto lenout;
1180 }
1181
1182 /* Dubious BSD thing... Probably nobody even uses it, but
1183 * the UNIX standard wants it for whatever reason... -DaveM
1184 */
1185 case SO_ACCEPTCONN:
1186 v.val = sk->sk_state == TCP_LISTEN;
1187 break;
1188
1189 case SO_PASSSEC:
1190 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1191 break;
1192
1193 case SO_PEERSEC:
1194 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1195
1196 case SO_MARK:
1197 v.val = sk->sk_mark;
1198 break;
1199
1200 case SO_RXQ_OVFL:
1201 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1202 break;
1203
1204 case SO_WIFI_STATUS:
1205 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1206 break;
1207
1208 case SO_PEEK_OFF:
1209 if (!sock->ops->set_peek_off)
1210 return -EOPNOTSUPP;
1211
1212 v.val = sk->sk_peek_off;
1213 break;
1214 case SO_NOFCS:
1215 v.val = sock_flag(sk, SOCK_NOFCS);
1216 break;
1217
1218 case SO_BINDTODEVICE:
1219 return sock_getbindtodevice(sk, optval, optlen, len);
1220
1221 case SO_GET_FILTER:
1222 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1223 if (len < 0)
1224 return len;
1225
1226 goto lenout;
1227
1228 case SO_LOCK_FILTER:
1229 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1230 break;
1231
1232 case SO_BPF_EXTENSIONS:
1233 v.val = bpf_tell_extensions();
1234 break;
1235
1236 case SO_SELECT_ERR_QUEUE:
1237 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1238 break;
1239
1240 #ifdef CONFIG_NET_RX_BUSY_POLL
1241 case SO_BUSY_POLL:
1242 v.val = sk->sk_ll_usec;
1243 break;
1244 #endif
1245
1246 case SO_MAX_PACING_RATE:
1247 v.val = sk->sk_max_pacing_rate;
1248 break;
1249
1250 case SO_INCOMING_CPU:
1251 v.val = sk->sk_incoming_cpu;
1252 break;
1253
1254 default:
1255 /* We implement the SO_SNDLOWAT etc to not be settable
1256 * (1003.1g 7).
1257 */
1258 return -ENOPROTOOPT;
1259 }
1260
1261 if (len > lv)
1262 len = lv;
1263 if (copy_to_user(optval, &v, len))
1264 return -EFAULT;
1265 lenout:
1266 if (put_user(len, optlen))
1267 return -EFAULT;
1268 return 0;
1269 }
1270
1271 /*
1272 * Initialize an sk_lock.
1273 *
1274 * (We also register the sk_lock with the lock validator.)
1275 */
1276 static inline void sock_lock_init(struct sock *sk)
1277 {
1278 sock_lock_init_class_and_name(sk,
1279 af_family_slock_key_strings[sk->sk_family],
1280 af_family_slock_keys + sk->sk_family,
1281 af_family_key_strings[sk->sk_family],
1282 af_family_keys + sk->sk_family);
1283 }
1284
1285 /*
1286 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1287 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1288 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1289 */
1290 static void sock_copy(struct sock *nsk, const struct sock *osk)
1291 {
1292 #ifdef CONFIG_SECURITY_NETWORK
1293 void *sptr = nsk->sk_security;
1294 #endif
1295 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1296
1297 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1298 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1299
1300 #ifdef CONFIG_SECURITY_NETWORK
1301 nsk->sk_security = sptr;
1302 security_sk_clone(osk, nsk);
1303 #endif
1304 }
1305
1306 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1307 {
1308 unsigned long nulls1, nulls2;
1309
1310 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1311 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1312 if (nulls1 > nulls2)
1313 swap(nulls1, nulls2);
1314
1315 if (nulls1 != 0)
1316 memset((char *)sk, 0, nulls1);
1317 memset((char *)sk + nulls1 + sizeof(void *), 0,
1318 nulls2 - nulls1 - sizeof(void *));
1319 memset((char *)sk + nulls2 + sizeof(void *), 0,
1320 size - nulls2 - sizeof(void *));
1321 }
1322 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1323
1324 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1325 int family)
1326 {
1327 struct sock *sk;
1328 struct kmem_cache *slab;
1329
1330 slab = prot->slab;
1331 if (slab != NULL) {
1332 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1333 if (!sk)
1334 return sk;
1335 if (priority & __GFP_ZERO) {
1336 if (prot->clear_sk)
1337 prot->clear_sk(sk, prot->obj_size);
1338 else
1339 sk_prot_clear_nulls(sk, prot->obj_size);
1340 }
1341 } else
1342 sk = kmalloc(prot->obj_size, priority);
1343
1344 if (sk != NULL) {
1345 kmemcheck_annotate_bitfield(sk, flags);
1346
1347 if (security_sk_alloc(sk, family, priority))
1348 goto out_free;
1349
1350 if (!try_module_get(prot->owner))
1351 goto out_free_sec;
1352 sk_tx_queue_clear(sk);
1353 cgroup_sk_alloc(&sk->sk_cgrp_data);
1354 }
1355
1356 return sk;
1357
1358 out_free_sec:
1359 security_sk_free(sk);
1360 out_free:
1361 if (slab != NULL)
1362 kmem_cache_free(slab, sk);
1363 else
1364 kfree(sk);
1365 return NULL;
1366 }
1367
1368 static void sk_prot_free(struct proto *prot, struct sock *sk)
1369 {
1370 struct kmem_cache *slab;
1371 struct module *owner;
1372
1373 owner = prot->owner;
1374 slab = prot->slab;
1375
1376 cgroup_sk_free(&sk->sk_cgrp_data);
1377 security_sk_free(sk);
1378 if (slab != NULL)
1379 kmem_cache_free(slab, sk);
1380 else
1381 kfree(sk);
1382 module_put(owner);
1383 }
1384
1385 /**
1386 * sk_alloc - All socket objects are allocated here
1387 * @net: the applicable net namespace
1388 * @family: protocol family
1389 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1390 * @prot: struct proto associated with this new sock instance
1391 * @kern: is this to be a kernel socket?
1392 */
1393 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1394 struct proto *prot, int kern)
1395 {
1396 struct sock *sk;
1397
1398 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1399 if (sk) {
1400 sk->sk_family = family;
1401 /*
1402 * See comment in struct sock definition to understand
1403 * why we need sk_prot_creator -acme
1404 */
1405 sk->sk_prot = sk->sk_prot_creator = prot;
1406 sock_lock_init(sk);
1407 sk->sk_net_refcnt = kern ? 0 : 1;
1408 if (likely(sk->sk_net_refcnt))
1409 get_net(net);
1410 sock_net_set(sk, net);
1411 atomic_set(&sk->sk_wmem_alloc, 1);
1412
1413 sock_update_classid(&sk->sk_cgrp_data);
1414 sock_update_netprioidx(&sk->sk_cgrp_data);
1415 }
1416
1417 return sk;
1418 }
1419 EXPORT_SYMBOL(sk_alloc);
1420
1421 void sk_destruct(struct sock *sk)
1422 {
1423 struct sk_filter *filter;
1424
1425 if (sk->sk_destruct)
1426 sk->sk_destruct(sk);
1427
1428 filter = rcu_dereference_check(sk->sk_filter,
1429 atomic_read(&sk->sk_wmem_alloc) == 0);
1430 if (filter) {
1431 sk_filter_uncharge(sk, filter);
1432 RCU_INIT_POINTER(sk->sk_filter, NULL);
1433 }
1434 if (rcu_access_pointer(sk->sk_reuseport_cb))
1435 reuseport_detach_sock(sk);
1436
1437 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1438
1439 if (atomic_read(&sk->sk_omem_alloc))
1440 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1441 __func__, atomic_read(&sk->sk_omem_alloc));
1442
1443 if (sk->sk_peer_cred)
1444 put_cred(sk->sk_peer_cred);
1445 put_pid(sk->sk_peer_pid);
1446 if (likely(sk->sk_net_refcnt))
1447 put_net(sock_net(sk));
1448 sk_prot_free(sk->sk_prot_creator, sk);
1449 }
1450
1451 static void __sk_free(struct sock *sk)
1452 {
1453 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1454 sock_diag_broadcast_destroy(sk);
1455 else
1456 sk_destruct(sk);
1457 }
1458
1459 void sk_free(struct sock *sk)
1460 {
1461 /*
1462 * We subtract one from sk_wmem_alloc and can know if
1463 * some packets are still in some tx queue.
1464 * If not null, sock_wfree() will call __sk_free(sk) later
1465 */
1466 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1467 __sk_free(sk);
1468 }
1469 EXPORT_SYMBOL(sk_free);
1470
1471 /**
1472 * sk_clone_lock - clone a socket, and lock its clone
1473 * @sk: the socket to clone
1474 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1475 *
1476 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1477 */
1478 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1479 {
1480 struct sock *newsk;
1481 bool is_charged = true;
1482
1483 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1484 if (newsk != NULL) {
1485 struct sk_filter *filter;
1486
1487 sock_copy(newsk, sk);
1488
1489 /* SANITY */
1490 if (likely(newsk->sk_net_refcnt))
1491 get_net(sock_net(newsk));
1492 sk_node_init(&newsk->sk_node);
1493 sock_lock_init(newsk);
1494 bh_lock_sock(newsk);
1495 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1496 newsk->sk_backlog.len = 0;
1497
1498 atomic_set(&newsk->sk_rmem_alloc, 0);
1499 /*
1500 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1501 */
1502 atomic_set(&newsk->sk_wmem_alloc, 1);
1503 atomic_set(&newsk->sk_omem_alloc, 0);
1504 skb_queue_head_init(&newsk->sk_receive_queue);
1505 skb_queue_head_init(&newsk->sk_write_queue);
1506
1507 rwlock_init(&newsk->sk_callback_lock);
1508 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1509 af_callback_keys + newsk->sk_family,
1510 af_family_clock_key_strings[newsk->sk_family]);
1511
1512 newsk->sk_dst_cache = NULL;
1513 newsk->sk_wmem_queued = 0;
1514 newsk->sk_forward_alloc = 0;
1515 newsk->sk_send_head = NULL;
1516 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1517
1518 sock_reset_flag(newsk, SOCK_DONE);
1519 skb_queue_head_init(&newsk->sk_error_queue);
1520
1521 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1522 if (filter != NULL)
1523 /* though it's an empty new sock, the charging may fail
1524 * if sysctl_optmem_max was changed between creation of
1525 * original socket and cloning
1526 */
1527 is_charged = sk_filter_charge(newsk, filter);
1528
1529 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1530 /* It is still raw copy of parent, so invalidate
1531 * destructor and make plain sk_free() */
1532 newsk->sk_destruct = NULL;
1533 bh_unlock_sock(newsk);
1534 sk_free(newsk);
1535 newsk = NULL;
1536 goto out;
1537 }
1538 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1539
1540 newsk->sk_err = 0;
1541 newsk->sk_priority = 0;
1542 newsk->sk_incoming_cpu = raw_smp_processor_id();
1543 atomic64_set(&newsk->sk_cookie, 0);
1544 /*
1545 * Before updating sk_refcnt, we must commit prior changes to memory
1546 * (Documentation/RCU/rculist_nulls.txt for details)
1547 */
1548 smp_wmb();
1549 atomic_set(&newsk->sk_refcnt, 2);
1550
1551 /*
1552 * Increment the counter in the same struct proto as the master
1553 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1554 * is the same as sk->sk_prot->socks, as this field was copied
1555 * with memcpy).
1556 *
1557 * This _changes_ the previous behaviour, where
1558 * tcp_create_openreq_child always was incrementing the
1559 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1560 * to be taken into account in all callers. -acme
1561 */
1562 sk_refcnt_debug_inc(newsk);
1563 sk_set_socket(newsk, NULL);
1564 newsk->sk_wq = NULL;
1565
1566 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
1567 sock_update_memcg(newsk);
1568
1569 if (newsk->sk_prot->sockets_allocated)
1570 sk_sockets_allocated_inc(newsk);
1571
1572 if (sock_needs_netstamp(sk) &&
1573 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1574 net_enable_timestamp();
1575 }
1576 out:
1577 return newsk;
1578 }
1579 EXPORT_SYMBOL_GPL(sk_clone_lock);
1580
1581 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1582 {
1583 u32 max_segs = 1;
1584
1585 sk_dst_set(sk, dst);
1586 sk->sk_route_caps = dst->dev->features;
1587 if (sk->sk_route_caps & NETIF_F_GSO)
1588 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1589 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1590 if (sk_can_gso(sk)) {
1591 if (dst->header_len) {
1592 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1593 } else {
1594 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1595 sk->sk_gso_max_size = dst->dev->gso_max_size;
1596 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1597 }
1598 }
1599 sk->sk_gso_max_segs = max_segs;
1600 }
1601 EXPORT_SYMBOL_GPL(sk_setup_caps);
1602
1603 /*
1604 * Simple resource managers for sockets.
1605 */
1606
1607
1608 /*
1609 * Write buffer destructor automatically called from kfree_skb.
1610 */
1611 void sock_wfree(struct sk_buff *skb)
1612 {
1613 struct sock *sk = skb->sk;
1614 unsigned int len = skb->truesize;
1615
1616 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1617 /*
1618 * Keep a reference on sk_wmem_alloc, this will be released
1619 * after sk_write_space() call
1620 */
1621 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1622 sk->sk_write_space(sk);
1623 len = 1;
1624 }
1625 /*
1626 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1627 * could not do because of in-flight packets
1628 */
1629 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1630 __sk_free(sk);
1631 }
1632 EXPORT_SYMBOL(sock_wfree);
1633
1634 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1635 {
1636 skb_orphan(skb);
1637 skb->sk = sk;
1638 #ifdef CONFIG_INET
1639 if (unlikely(!sk_fullsock(sk))) {
1640 skb->destructor = sock_edemux;
1641 sock_hold(sk);
1642 return;
1643 }
1644 #endif
1645 skb->destructor = sock_wfree;
1646 skb_set_hash_from_sk(skb, sk);
1647 /*
1648 * We used to take a refcount on sk, but following operation
1649 * is enough to guarantee sk_free() wont free this sock until
1650 * all in-flight packets are completed
1651 */
1652 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1653 }
1654 EXPORT_SYMBOL(skb_set_owner_w);
1655
1656 void skb_orphan_partial(struct sk_buff *skb)
1657 {
1658 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1659 * so we do not completely orphan skb, but transfert all
1660 * accounted bytes but one, to avoid unexpected reorders.
1661 */
1662 if (skb->destructor == sock_wfree
1663 #ifdef CONFIG_INET
1664 || skb->destructor == tcp_wfree
1665 #endif
1666 ) {
1667 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1668 skb->truesize = 1;
1669 } else {
1670 skb_orphan(skb);
1671 }
1672 }
1673 EXPORT_SYMBOL(skb_orphan_partial);
1674
1675 /*
1676 * Read buffer destructor automatically called from kfree_skb.
1677 */
1678 void sock_rfree(struct sk_buff *skb)
1679 {
1680 struct sock *sk = skb->sk;
1681 unsigned int len = skb->truesize;
1682
1683 atomic_sub(len, &sk->sk_rmem_alloc);
1684 sk_mem_uncharge(sk, len);
1685 }
1686 EXPORT_SYMBOL(sock_rfree);
1687
1688 /*
1689 * Buffer destructor for skbs that are not used directly in read or write
1690 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1691 */
1692 void sock_efree(struct sk_buff *skb)
1693 {
1694 sock_put(skb->sk);
1695 }
1696 EXPORT_SYMBOL(sock_efree);
1697
1698 kuid_t sock_i_uid(struct sock *sk)
1699 {
1700 kuid_t uid;
1701
1702 read_lock_bh(&sk->sk_callback_lock);
1703 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1704 read_unlock_bh(&sk->sk_callback_lock);
1705 return uid;
1706 }
1707 EXPORT_SYMBOL(sock_i_uid);
1708
1709 unsigned long sock_i_ino(struct sock *sk)
1710 {
1711 unsigned long ino;
1712
1713 read_lock_bh(&sk->sk_callback_lock);
1714 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1715 read_unlock_bh(&sk->sk_callback_lock);
1716 return ino;
1717 }
1718 EXPORT_SYMBOL(sock_i_ino);
1719
1720 /*
1721 * Allocate a skb from the socket's send buffer.
1722 */
1723 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1724 gfp_t priority)
1725 {
1726 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1727 struct sk_buff *skb = alloc_skb(size, priority);
1728 if (skb) {
1729 skb_set_owner_w(skb, sk);
1730 return skb;
1731 }
1732 }
1733 return NULL;
1734 }
1735 EXPORT_SYMBOL(sock_wmalloc);
1736
1737 /*
1738 * Allocate a memory block from the socket's option memory buffer.
1739 */
1740 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1741 {
1742 if ((unsigned int)size <= sysctl_optmem_max &&
1743 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1744 void *mem;
1745 /* First do the add, to avoid the race if kmalloc
1746 * might sleep.
1747 */
1748 atomic_add(size, &sk->sk_omem_alloc);
1749 mem = kmalloc(size, priority);
1750 if (mem)
1751 return mem;
1752 atomic_sub(size, &sk->sk_omem_alloc);
1753 }
1754 return NULL;
1755 }
1756 EXPORT_SYMBOL(sock_kmalloc);
1757
1758 /* Free an option memory block. Note, we actually want the inline
1759 * here as this allows gcc to detect the nullify and fold away the
1760 * condition entirely.
1761 */
1762 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1763 const bool nullify)
1764 {
1765 if (WARN_ON_ONCE(!mem))
1766 return;
1767 if (nullify)
1768 kzfree(mem);
1769 else
1770 kfree(mem);
1771 atomic_sub(size, &sk->sk_omem_alloc);
1772 }
1773
1774 void sock_kfree_s(struct sock *sk, void *mem, int size)
1775 {
1776 __sock_kfree_s(sk, mem, size, false);
1777 }
1778 EXPORT_SYMBOL(sock_kfree_s);
1779
1780 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1781 {
1782 __sock_kfree_s(sk, mem, size, true);
1783 }
1784 EXPORT_SYMBOL(sock_kzfree_s);
1785
1786 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1787 I think, these locks should be removed for datagram sockets.
1788 */
1789 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1790 {
1791 DEFINE_WAIT(wait);
1792
1793 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1794 for (;;) {
1795 if (!timeo)
1796 break;
1797 if (signal_pending(current))
1798 break;
1799 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1800 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1801 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1802 break;
1803 if (sk->sk_shutdown & SEND_SHUTDOWN)
1804 break;
1805 if (sk->sk_err)
1806 break;
1807 timeo = schedule_timeout(timeo);
1808 }
1809 finish_wait(sk_sleep(sk), &wait);
1810 return timeo;
1811 }
1812
1813
1814 /*
1815 * Generic send/receive buffer handlers
1816 */
1817
1818 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1819 unsigned long data_len, int noblock,
1820 int *errcode, int max_page_order)
1821 {
1822 struct sk_buff *skb;
1823 long timeo;
1824 int err;
1825
1826 timeo = sock_sndtimeo(sk, noblock);
1827 for (;;) {
1828 err = sock_error(sk);
1829 if (err != 0)
1830 goto failure;
1831
1832 err = -EPIPE;
1833 if (sk->sk_shutdown & SEND_SHUTDOWN)
1834 goto failure;
1835
1836 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1837 break;
1838
1839 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1840 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1841 err = -EAGAIN;
1842 if (!timeo)
1843 goto failure;
1844 if (signal_pending(current))
1845 goto interrupted;
1846 timeo = sock_wait_for_wmem(sk, timeo);
1847 }
1848 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1849 errcode, sk->sk_allocation);
1850 if (skb)
1851 skb_set_owner_w(skb, sk);
1852 return skb;
1853
1854 interrupted:
1855 err = sock_intr_errno(timeo);
1856 failure:
1857 *errcode = err;
1858 return NULL;
1859 }
1860 EXPORT_SYMBOL(sock_alloc_send_pskb);
1861
1862 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1863 int noblock, int *errcode)
1864 {
1865 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1866 }
1867 EXPORT_SYMBOL(sock_alloc_send_skb);
1868
1869 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1870 struct sockcm_cookie *sockc)
1871 {
1872 struct cmsghdr *cmsg;
1873
1874 for_each_cmsghdr(cmsg, msg) {
1875 if (!CMSG_OK(msg, cmsg))
1876 return -EINVAL;
1877 if (cmsg->cmsg_level != SOL_SOCKET)
1878 continue;
1879 switch (cmsg->cmsg_type) {
1880 case SO_MARK:
1881 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1882 return -EPERM;
1883 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1884 return -EINVAL;
1885 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
1886 break;
1887 default:
1888 return -EINVAL;
1889 }
1890 }
1891 return 0;
1892 }
1893 EXPORT_SYMBOL(sock_cmsg_send);
1894
1895 /* On 32bit arches, an skb frag is limited to 2^15 */
1896 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1897
1898 /**
1899 * skb_page_frag_refill - check that a page_frag contains enough room
1900 * @sz: minimum size of the fragment we want to get
1901 * @pfrag: pointer to page_frag
1902 * @gfp: priority for memory allocation
1903 *
1904 * Note: While this allocator tries to use high order pages, there is
1905 * no guarantee that allocations succeed. Therefore, @sz MUST be
1906 * less or equal than PAGE_SIZE.
1907 */
1908 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1909 {
1910 if (pfrag->page) {
1911 if (page_ref_count(pfrag->page) == 1) {
1912 pfrag->offset = 0;
1913 return true;
1914 }
1915 if (pfrag->offset + sz <= pfrag->size)
1916 return true;
1917 put_page(pfrag->page);
1918 }
1919
1920 pfrag->offset = 0;
1921 if (SKB_FRAG_PAGE_ORDER) {
1922 /* Avoid direct reclaim but allow kswapd to wake */
1923 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
1924 __GFP_COMP | __GFP_NOWARN |
1925 __GFP_NORETRY,
1926 SKB_FRAG_PAGE_ORDER);
1927 if (likely(pfrag->page)) {
1928 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1929 return true;
1930 }
1931 }
1932 pfrag->page = alloc_page(gfp);
1933 if (likely(pfrag->page)) {
1934 pfrag->size = PAGE_SIZE;
1935 return true;
1936 }
1937 return false;
1938 }
1939 EXPORT_SYMBOL(skb_page_frag_refill);
1940
1941 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1942 {
1943 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1944 return true;
1945
1946 sk_enter_memory_pressure(sk);
1947 sk_stream_moderate_sndbuf(sk);
1948 return false;
1949 }
1950 EXPORT_SYMBOL(sk_page_frag_refill);
1951
1952 static void __lock_sock(struct sock *sk)
1953 __releases(&sk->sk_lock.slock)
1954 __acquires(&sk->sk_lock.slock)
1955 {
1956 DEFINE_WAIT(wait);
1957
1958 for (;;) {
1959 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1960 TASK_UNINTERRUPTIBLE);
1961 spin_unlock_bh(&sk->sk_lock.slock);
1962 schedule();
1963 spin_lock_bh(&sk->sk_lock.slock);
1964 if (!sock_owned_by_user(sk))
1965 break;
1966 }
1967 finish_wait(&sk->sk_lock.wq, &wait);
1968 }
1969
1970 static void __release_sock(struct sock *sk)
1971 __releases(&sk->sk_lock.slock)
1972 __acquires(&sk->sk_lock.slock)
1973 {
1974 struct sk_buff *skb = sk->sk_backlog.head;
1975
1976 do {
1977 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1978 bh_unlock_sock(sk);
1979
1980 do {
1981 struct sk_buff *next = skb->next;
1982
1983 prefetch(next);
1984 WARN_ON_ONCE(skb_dst_is_noref(skb));
1985 skb->next = NULL;
1986 sk_backlog_rcv(sk, skb);
1987
1988 /*
1989 * We are in process context here with softirqs
1990 * disabled, use cond_resched_softirq() to preempt.
1991 * This is safe to do because we've taken the backlog
1992 * queue private:
1993 */
1994 cond_resched_softirq();
1995
1996 skb = next;
1997 } while (skb != NULL);
1998
1999 bh_lock_sock(sk);
2000 } while ((skb = sk->sk_backlog.head) != NULL);
2001
2002 /*
2003 * Doing the zeroing here guarantee we can not loop forever
2004 * while a wild producer attempts to flood us.
2005 */
2006 sk->sk_backlog.len = 0;
2007 }
2008
2009 /**
2010 * sk_wait_data - wait for data to arrive at sk_receive_queue
2011 * @sk: sock to wait on
2012 * @timeo: for how long
2013 * @skb: last skb seen on sk_receive_queue
2014 *
2015 * Now socket state including sk->sk_err is changed only under lock,
2016 * hence we may omit checks after joining wait queue.
2017 * We check receive queue before schedule() only as optimization;
2018 * it is very likely that release_sock() added new data.
2019 */
2020 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2021 {
2022 int rc;
2023 DEFINE_WAIT(wait);
2024
2025 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2026 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2027 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb);
2028 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2029 finish_wait(sk_sleep(sk), &wait);
2030 return rc;
2031 }
2032 EXPORT_SYMBOL(sk_wait_data);
2033
2034 /**
2035 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2036 * @sk: socket
2037 * @size: memory size to allocate
2038 * @kind: allocation type
2039 *
2040 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2041 * rmem allocation. This function assumes that protocols which have
2042 * memory_pressure use sk_wmem_queued as write buffer accounting.
2043 */
2044 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2045 {
2046 struct proto *prot = sk->sk_prot;
2047 int amt = sk_mem_pages(size);
2048 long allocated;
2049
2050 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2051
2052 allocated = sk_memory_allocated_add(sk, amt);
2053
2054 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2055 !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2056 goto suppress_allocation;
2057
2058 /* Under limit. */
2059 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2060 sk_leave_memory_pressure(sk);
2061 return 1;
2062 }
2063
2064 /* Under pressure. */
2065 if (allocated > sk_prot_mem_limits(sk, 1))
2066 sk_enter_memory_pressure(sk);
2067
2068 /* Over hard limit. */
2069 if (allocated > sk_prot_mem_limits(sk, 2))
2070 goto suppress_allocation;
2071
2072 /* guarantee minimum buffer size under pressure */
2073 if (kind == SK_MEM_RECV) {
2074 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2075 return 1;
2076
2077 } else { /* SK_MEM_SEND */
2078 if (sk->sk_type == SOCK_STREAM) {
2079 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2080 return 1;
2081 } else if (atomic_read(&sk->sk_wmem_alloc) <
2082 prot->sysctl_wmem[0])
2083 return 1;
2084 }
2085
2086 if (sk_has_memory_pressure(sk)) {
2087 int alloc;
2088
2089 if (!sk_under_memory_pressure(sk))
2090 return 1;
2091 alloc = sk_sockets_allocated_read_positive(sk);
2092 if (sk_prot_mem_limits(sk, 2) > alloc *
2093 sk_mem_pages(sk->sk_wmem_queued +
2094 atomic_read(&sk->sk_rmem_alloc) +
2095 sk->sk_forward_alloc))
2096 return 1;
2097 }
2098
2099 suppress_allocation:
2100
2101 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2102 sk_stream_moderate_sndbuf(sk);
2103
2104 /* Fail only if socket is _under_ its sndbuf.
2105 * In this case we cannot block, so that we have to fail.
2106 */
2107 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2108 return 1;
2109 }
2110
2111 trace_sock_exceed_buf_limit(sk, prot, allocated);
2112
2113 /* Alas. Undo changes. */
2114 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2115
2116 sk_memory_allocated_sub(sk, amt);
2117
2118 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2119 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2120
2121 return 0;
2122 }
2123 EXPORT_SYMBOL(__sk_mem_schedule);
2124
2125 /**
2126 * __sk_mem_reclaim - reclaim memory_allocated
2127 * @sk: socket
2128 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2129 */
2130 void __sk_mem_reclaim(struct sock *sk, int amount)
2131 {
2132 amount >>= SK_MEM_QUANTUM_SHIFT;
2133 sk_memory_allocated_sub(sk, amount);
2134 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2135
2136 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2137 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2138
2139 if (sk_under_memory_pressure(sk) &&
2140 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2141 sk_leave_memory_pressure(sk);
2142 }
2143 EXPORT_SYMBOL(__sk_mem_reclaim);
2144
2145
2146 /*
2147 * Set of default routines for initialising struct proto_ops when
2148 * the protocol does not support a particular function. In certain
2149 * cases where it makes no sense for a protocol to have a "do nothing"
2150 * function, some default processing is provided.
2151 */
2152
2153 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2154 {
2155 return -EOPNOTSUPP;
2156 }
2157 EXPORT_SYMBOL(sock_no_bind);
2158
2159 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2160 int len, int flags)
2161 {
2162 return -EOPNOTSUPP;
2163 }
2164 EXPORT_SYMBOL(sock_no_connect);
2165
2166 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2167 {
2168 return -EOPNOTSUPP;
2169 }
2170 EXPORT_SYMBOL(sock_no_socketpair);
2171
2172 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2173 {
2174 return -EOPNOTSUPP;
2175 }
2176 EXPORT_SYMBOL(sock_no_accept);
2177
2178 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2179 int *len, int peer)
2180 {
2181 return -EOPNOTSUPP;
2182 }
2183 EXPORT_SYMBOL(sock_no_getname);
2184
2185 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2186 {
2187 return 0;
2188 }
2189 EXPORT_SYMBOL(sock_no_poll);
2190
2191 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2192 {
2193 return -EOPNOTSUPP;
2194 }
2195 EXPORT_SYMBOL(sock_no_ioctl);
2196
2197 int sock_no_listen(struct socket *sock, int backlog)
2198 {
2199 return -EOPNOTSUPP;
2200 }
2201 EXPORT_SYMBOL(sock_no_listen);
2202
2203 int sock_no_shutdown(struct socket *sock, int how)
2204 {
2205 return -EOPNOTSUPP;
2206 }
2207 EXPORT_SYMBOL(sock_no_shutdown);
2208
2209 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2210 char __user *optval, unsigned int optlen)
2211 {
2212 return -EOPNOTSUPP;
2213 }
2214 EXPORT_SYMBOL(sock_no_setsockopt);
2215
2216 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2217 char __user *optval, int __user *optlen)
2218 {
2219 return -EOPNOTSUPP;
2220 }
2221 EXPORT_SYMBOL(sock_no_getsockopt);
2222
2223 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2224 {
2225 return -EOPNOTSUPP;
2226 }
2227 EXPORT_SYMBOL(sock_no_sendmsg);
2228
2229 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2230 int flags)
2231 {
2232 return -EOPNOTSUPP;
2233 }
2234 EXPORT_SYMBOL(sock_no_recvmsg);
2235
2236 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2237 {
2238 /* Mirror missing mmap method error code */
2239 return -ENODEV;
2240 }
2241 EXPORT_SYMBOL(sock_no_mmap);
2242
2243 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2244 {
2245 ssize_t res;
2246 struct msghdr msg = {.msg_flags = flags};
2247 struct kvec iov;
2248 char *kaddr = kmap(page);
2249 iov.iov_base = kaddr + offset;
2250 iov.iov_len = size;
2251 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2252 kunmap(page);
2253 return res;
2254 }
2255 EXPORT_SYMBOL(sock_no_sendpage);
2256
2257 /*
2258 * Default Socket Callbacks
2259 */
2260
2261 static void sock_def_wakeup(struct sock *sk)
2262 {
2263 struct socket_wq *wq;
2264
2265 rcu_read_lock();
2266 wq = rcu_dereference(sk->sk_wq);
2267 if (skwq_has_sleeper(wq))
2268 wake_up_interruptible_all(&wq->wait);
2269 rcu_read_unlock();
2270 }
2271
2272 static void sock_def_error_report(struct sock *sk)
2273 {
2274 struct socket_wq *wq;
2275
2276 rcu_read_lock();
2277 wq = rcu_dereference(sk->sk_wq);
2278 if (skwq_has_sleeper(wq))
2279 wake_up_interruptible_poll(&wq->wait, POLLERR);
2280 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2281 rcu_read_unlock();
2282 }
2283
2284 static void sock_def_readable(struct sock *sk)
2285 {
2286 struct socket_wq *wq;
2287
2288 rcu_read_lock();
2289 wq = rcu_dereference(sk->sk_wq);
2290 if (skwq_has_sleeper(wq))
2291 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2292 POLLRDNORM | POLLRDBAND);
2293 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2294 rcu_read_unlock();
2295 }
2296
2297 static void sock_def_write_space(struct sock *sk)
2298 {
2299 struct socket_wq *wq;
2300
2301 rcu_read_lock();
2302
2303 /* Do not wake up a writer until he can make "significant"
2304 * progress. --DaveM
2305 */
2306 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2307 wq = rcu_dereference(sk->sk_wq);
2308 if (skwq_has_sleeper(wq))
2309 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2310 POLLWRNORM | POLLWRBAND);
2311
2312 /* Should agree with poll, otherwise some programs break */
2313 if (sock_writeable(sk))
2314 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2315 }
2316
2317 rcu_read_unlock();
2318 }
2319
2320 static void sock_def_destruct(struct sock *sk)
2321 {
2322 }
2323
2324 void sk_send_sigurg(struct sock *sk)
2325 {
2326 if (sk->sk_socket && sk->sk_socket->file)
2327 if (send_sigurg(&sk->sk_socket->file->f_owner))
2328 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2329 }
2330 EXPORT_SYMBOL(sk_send_sigurg);
2331
2332 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2333 unsigned long expires)
2334 {
2335 if (!mod_timer(timer, expires))
2336 sock_hold(sk);
2337 }
2338 EXPORT_SYMBOL(sk_reset_timer);
2339
2340 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2341 {
2342 if (del_timer(timer))
2343 __sock_put(sk);
2344 }
2345 EXPORT_SYMBOL(sk_stop_timer);
2346
2347 void sock_init_data(struct socket *sock, struct sock *sk)
2348 {
2349 skb_queue_head_init(&sk->sk_receive_queue);
2350 skb_queue_head_init(&sk->sk_write_queue);
2351 skb_queue_head_init(&sk->sk_error_queue);
2352
2353 sk->sk_send_head = NULL;
2354
2355 init_timer(&sk->sk_timer);
2356
2357 sk->sk_allocation = GFP_KERNEL;
2358 sk->sk_rcvbuf = sysctl_rmem_default;
2359 sk->sk_sndbuf = sysctl_wmem_default;
2360 sk->sk_state = TCP_CLOSE;
2361 sk_set_socket(sk, sock);
2362
2363 sock_set_flag(sk, SOCK_ZAPPED);
2364
2365 if (sock) {
2366 sk->sk_type = sock->type;
2367 sk->sk_wq = sock->wq;
2368 sock->sk = sk;
2369 } else
2370 sk->sk_wq = NULL;
2371
2372 rwlock_init(&sk->sk_callback_lock);
2373 lockdep_set_class_and_name(&sk->sk_callback_lock,
2374 af_callback_keys + sk->sk_family,
2375 af_family_clock_key_strings[sk->sk_family]);
2376
2377 sk->sk_state_change = sock_def_wakeup;
2378 sk->sk_data_ready = sock_def_readable;
2379 sk->sk_write_space = sock_def_write_space;
2380 sk->sk_error_report = sock_def_error_report;
2381 sk->sk_destruct = sock_def_destruct;
2382
2383 sk->sk_frag.page = NULL;
2384 sk->sk_frag.offset = 0;
2385 sk->sk_peek_off = -1;
2386
2387 sk->sk_peer_pid = NULL;
2388 sk->sk_peer_cred = NULL;
2389 sk->sk_write_pending = 0;
2390 sk->sk_rcvlowat = 1;
2391 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2392 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2393
2394 sk->sk_stamp = ktime_set(-1L, 0);
2395
2396 #ifdef CONFIG_NET_RX_BUSY_POLL
2397 sk->sk_napi_id = 0;
2398 sk->sk_ll_usec = sysctl_net_busy_read;
2399 #endif
2400
2401 sk->sk_max_pacing_rate = ~0U;
2402 sk->sk_pacing_rate = ~0U;
2403 sk->sk_incoming_cpu = -1;
2404 /*
2405 * Before updating sk_refcnt, we must commit prior changes to memory
2406 * (Documentation/RCU/rculist_nulls.txt for details)
2407 */
2408 smp_wmb();
2409 atomic_set(&sk->sk_refcnt, 1);
2410 atomic_set(&sk->sk_drops, 0);
2411 }
2412 EXPORT_SYMBOL(sock_init_data);
2413
2414 void lock_sock_nested(struct sock *sk, int subclass)
2415 {
2416 might_sleep();
2417 spin_lock_bh(&sk->sk_lock.slock);
2418 if (sk->sk_lock.owned)
2419 __lock_sock(sk);
2420 sk->sk_lock.owned = 1;
2421 spin_unlock(&sk->sk_lock.slock);
2422 /*
2423 * The sk_lock has mutex_lock() semantics here:
2424 */
2425 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2426 local_bh_enable();
2427 }
2428 EXPORT_SYMBOL(lock_sock_nested);
2429
2430 void release_sock(struct sock *sk)
2431 {
2432 /*
2433 * The sk_lock has mutex_unlock() semantics:
2434 */
2435 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2436
2437 spin_lock_bh(&sk->sk_lock.slock);
2438 if (sk->sk_backlog.tail)
2439 __release_sock(sk);
2440
2441 /* Warning : release_cb() might need to release sk ownership,
2442 * ie call sock_release_ownership(sk) before us.
2443 */
2444 if (sk->sk_prot->release_cb)
2445 sk->sk_prot->release_cb(sk);
2446
2447 sock_release_ownership(sk);
2448 if (waitqueue_active(&sk->sk_lock.wq))
2449 wake_up(&sk->sk_lock.wq);
2450 spin_unlock_bh(&sk->sk_lock.slock);
2451 }
2452 EXPORT_SYMBOL(release_sock);
2453
2454 /**
2455 * lock_sock_fast - fast version of lock_sock
2456 * @sk: socket
2457 *
2458 * This version should be used for very small section, where process wont block
2459 * return false if fast path is taken
2460 * sk_lock.slock locked, owned = 0, BH disabled
2461 * return true if slow path is taken
2462 * sk_lock.slock unlocked, owned = 1, BH enabled
2463 */
2464 bool lock_sock_fast(struct sock *sk)
2465 {
2466 might_sleep();
2467 spin_lock_bh(&sk->sk_lock.slock);
2468
2469 if (!sk->sk_lock.owned)
2470 /*
2471 * Note : We must disable BH
2472 */
2473 return false;
2474
2475 __lock_sock(sk);
2476 sk->sk_lock.owned = 1;
2477 spin_unlock(&sk->sk_lock.slock);
2478 /*
2479 * The sk_lock has mutex_lock() semantics here:
2480 */
2481 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2482 local_bh_enable();
2483 return true;
2484 }
2485 EXPORT_SYMBOL(lock_sock_fast);
2486
2487 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2488 {
2489 struct timeval tv;
2490 if (!sock_flag(sk, SOCK_TIMESTAMP))
2491 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2492 tv = ktime_to_timeval(sk->sk_stamp);
2493 if (tv.tv_sec == -1)
2494 return -ENOENT;
2495 if (tv.tv_sec == 0) {
2496 sk->sk_stamp = ktime_get_real();
2497 tv = ktime_to_timeval(sk->sk_stamp);
2498 }
2499 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2500 }
2501 EXPORT_SYMBOL(sock_get_timestamp);
2502
2503 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2504 {
2505 struct timespec ts;
2506 if (!sock_flag(sk, SOCK_TIMESTAMP))
2507 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2508 ts = ktime_to_timespec(sk->sk_stamp);
2509 if (ts.tv_sec == -1)
2510 return -ENOENT;
2511 if (ts.tv_sec == 0) {
2512 sk->sk_stamp = ktime_get_real();
2513 ts = ktime_to_timespec(sk->sk_stamp);
2514 }
2515 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2516 }
2517 EXPORT_SYMBOL(sock_get_timestampns);
2518
2519 void sock_enable_timestamp(struct sock *sk, int flag)
2520 {
2521 if (!sock_flag(sk, flag)) {
2522 unsigned long previous_flags = sk->sk_flags;
2523
2524 sock_set_flag(sk, flag);
2525 /*
2526 * we just set one of the two flags which require net
2527 * time stamping, but time stamping might have been on
2528 * already because of the other one
2529 */
2530 if (sock_needs_netstamp(sk) &&
2531 !(previous_flags & SK_FLAGS_TIMESTAMP))
2532 net_enable_timestamp();
2533 }
2534 }
2535
2536 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2537 int level, int type)
2538 {
2539 struct sock_exterr_skb *serr;
2540 struct sk_buff *skb;
2541 int copied, err;
2542
2543 err = -EAGAIN;
2544 skb = sock_dequeue_err_skb(sk);
2545 if (skb == NULL)
2546 goto out;
2547
2548 copied = skb->len;
2549 if (copied > len) {
2550 msg->msg_flags |= MSG_TRUNC;
2551 copied = len;
2552 }
2553 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2554 if (err)
2555 goto out_free_skb;
2556
2557 sock_recv_timestamp(msg, sk, skb);
2558
2559 serr = SKB_EXT_ERR(skb);
2560 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2561
2562 msg->msg_flags |= MSG_ERRQUEUE;
2563 err = copied;
2564
2565 out_free_skb:
2566 kfree_skb(skb);
2567 out:
2568 return err;
2569 }
2570 EXPORT_SYMBOL(sock_recv_errqueue);
2571
2572 /*
2573 * Get a socket option on an socket.
2574 *
2575 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2576 * asynchronous errors should be reported by getsockopt. We assume
2577 * this means if you specify SO_ERROR (otherwise whats the point of it).
2578 */
2579 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2580 char __user *optval, int __user *optlen)
2581 {
2582 struct sock *sk = sock->sk;
2583
2584 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2585 }
2586 EXPORT_SYMBOL(sock_common_getsockopt);
2587
2588 #ifdef CONFIG_COMPAT
2589 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2590 char __user *optval, int __user *optlen)
2591 {
2592 struct sock *sk = sock->sk;
2593
2594 if (sk->sk_prot->compat_getsockopt != NULL)
2595 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2596 optval, optlen);
2597 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2598 }
2599 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2600 #endif
2601
2602 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2603 int flags)
2604 {
2605 struct sock *sk = sock->sk;
2606 int addr_len = 0;
2607 int err;
2608
2609 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2610 flags & ~MSG_DONTWAIT, &addr_len);
2611 if (err >= 0)
2612 msg->msg_namelen = addr_len;
2613 return err;
2614 }
2615 EXPORT_SYMBOL(sock_common_recvmsg);
2616
2617 /*
2618 * Set socket options on an inet socket.
2619 */
2620 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2621 char __user *optval, unsigned int optlen)
2622 {
2623 struct sock *sk = sock->sk;
2624
2625 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2626 }
2627 EXPORT_SYMBOL(sock_common_setsockopt);
2628
2629 #ifdef CONFIG_COMPAT
2630 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2631 char __user *optval, unsigned int optlen)
2632 {
2633 struct sock *sk = sock->sk;
2634
2635 if (sk->sk_prot->compat_setsockopt != NULL)
2636 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2637 optval, optlen);
2638 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2639 }
2640 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2641 #endif
2642
2643 void sk_common_release(struct sock *sk)
2644 {
2645 if (sk->sk_prot->destroy)
2646 sk->sk_prot->destroy(sk);
2647
2648 /*
2649 * Observation: when sock_common_release is called, processes have
2650 * no access to socket. But net still has.
2651 * Step one, detach it from networking:
2652 *
2653 * A. Remove from hash tables.
2654 */
2655
2656 sk->sk_prot->unhash(sk);
2657
2658 /*
2659 * In this point socket cannot receive new packets, but it is possible
2660 * that some packets are in flight because some CPU runs receiver and
2661 * did hash table lookup before we unhashed socket. They will achieve
2662 * receive queue and will be purged by socket destructor.
2663 *
2664 * Also we still have packets pending on receive queue and probably,
2665 * our own packets waiting in device queues. sock_destroy will drain
2666 * receive queue, but transmitted packets will delay socket destruction
2667 * until the last reference will be released.
2668 */
2669
2670 sock_orphan(sk);
2671
2672 xfrm_sk_free_policy(sk);
2673
2674 sk_refcnt_debug_release(sk);
2675
2676 if (sk->sk_frag.page) {
2677 put_page(sk->sk_frag.page);
2678 sk->sk_frag.page = NULL;
2679 }
2680
2681 sock_put(sk);
2682 }
2683 EXPORT_SYMBOL(sk_common_release);
2684
2685 #ifdef CONFIG_PROC_FS
2686 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2687 struct prot_inuse {
2688 int val[PROTO_INUSE_NR];
2689 };
2690
2691 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2692
2693 #ifdef CONFIG_NET_NS
2694 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2695 {
2696 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2697 }
2698 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2699
2700 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2701 {
2702 int cpu, idx = prot->inuse_idx;
2703 int res = 0;
2704
2705 for_each_possible_cpu(cpu)
2706 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2707
2708 return res >= 0 ? res : 0;
2709 }
2710 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2711
2712 static int __net_init sock_inuse_init_net(struct net *net)
2713 {
2714 net->core.inuse = alloc_percpu(struct prot_inuse);
2715 return net->core.inuse ? 0 : -ENOMEM;
2716 }
2717
2718 static void __net_exit sock_inuse_exit_net(struct net *net)
2719 {
2720 free_percpu(net->core.inuse);
2721 }
2722
2723 static struct pernet_operations net_inuse_ops = {
2724 .init = sock_inuse_init_net,
2725 .exit = sock_inuse_exit_net,
2726 };
2727
2728 static __init int net_inuse_init(void)
2729 {
2730 if (register_pernet_subsys(&net_inuse_ops))
2731 panic("Cannot initialize net inuse counters");
2732
2733 return 0;
2734 }
2735
2736 core_initcall(net_inuse_init);
2737 #else
2738 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2739
2740 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2741 {
2742 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2743 }
2744 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2745
2746 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2747 {
2748 int cpu, idx = prot->inuse_idx;
2749 int res = 0;
2750
2751 for_each_possible_cpu(cpu)
2752 res += per_cpu(prot_inuse, cpu).val[idx];
2753
2754 return res >= 0 ? res : 0;
2755 }
2756 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2757 #endif
2758
2759 static void assign_proto_idx(struct proto *prot)
2760 {
2761 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2762
2763 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2764 pr_err("PROTO_INUSE_NR exhausted\n");
2765 return;
2766 }
2767
2768 set_bit(prot->inuse_idx, proto_inuse_idx);
2769 }
2770
2771 static void release_proto_idx(struct proto *prot)
2772 {
2773 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2774 clear_bit(prot->inuse_idx, proto_inuse_idx);
2775 }
2776 #else
2777 static inline void assign_proto_idx(struct proto *prot)
2778 {
2779 }
2780
2781 static inline void release_proto_idx(struct proto *prot)
2782 {
2783 }
2784 #endif
2785
2786 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2787 {
2788 if (!rsk_prot)
2789 return;
2790 kfree(rsk_prot->slab_name);
2791 rsk_prot->slab_name = NULL;
2792 kmem_cache_destroy(rsk_prot->slab);
2793 rsk_prot->slab = NULL;
2794 }
2795
2796 static int req_prot_init(const struct proto *prot)
2797 {
2798 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2799
2800 if (!rsk_prot)
2801 return 0;
2802
2803 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2804 prot->name);
2805 if (!rsk_prot->slab_name)
2806 return -ENOMEM;
2807
2808 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2809 rsk_prot->obj_size, 0,
2810 prot->slab_flags, NULL);
2811
2812 if (!rsk_prot->slab) {
2813 pr_crit("%s: Can't create request sock SLAB cache!\n",
2814 prot->name);
2815 return -ENOMEM;
2816 }
2817 return 0;
2818 }
2819
2820 int proto_register(struct proto *prot, int alloc_slab)
2821 {
2822 if (alloc_slab) {
2823 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2824 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2825 NULL);
2826
2827 if (prot->slab == NULL) {
2828 pr_crit("%s: Can't create sock SLAB cache!\n",
2829 prot->name);
2830 goto out;
2831 }
2832
2833 if (req_prot_init(prot))
2834 goto out_free_request_sock_slab;
2835
2836 if (prot->twsk_prot != NULL) {
2837 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2838
2839 if (prot->twsk_prot->twsk_slab_name == NULL)
2840 goto out_free_request_sock_slab;
2841
2842 prot->twsk_prot->twsk_slab =
2843 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2844 prot->twsk_prot->twsk_obj_size,
2845 0,
2846 prot->slab_flags,
2847 NULL);
2848 if (prot->twsk_prot->twsk_slab == NULL)
2849 goto out_free_timewait_sock_slab_name;
2850 }
2851 }
2852
2853 mutex_lock(&proto_list_mutex);
2854 list_add(&prot->node, &proto_list);
2855 assign_proto_idx(prot);
2856 mutex_unlock(&proto_list_mutex);
2857 return 0;
2858
2859 out_free_timewait_sock_slab_name:
2860 kfree(prot->twsk_prot->twsk_slab_name);
2861 out_free_request_sock_slab:
2862 req_prot_cleanup(prot->rsk_prot);
2863
2864 kmem_cache_destroy(prot->slab);
2865 prot->slab = NULL;
2866 out:
2867 return -ENOBUFS;
2868 }
2869 EXPORT_SYMBOL(proto_register);
2870
2871 void proto_unregister(struct proto *prot)
2872 {
2873 mutex_lock(&proto_list_mutex);
2874 release_proto_idx(prot);
2875 list_del(&prot->node);
2876 mutex_unlock(&proto_list_mutex);
2877
2878 kmem_cache_destroy(prot->slab);
2879 prot->slab = NULL;
2880
2881 req_prot_cleanup(prot->rsk_prot);
2882
2883 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2884 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2885 kfree(prot->twsk_prot->twsk_slab_name);
2886 prot->twsk_prot->twsk_slab = NULL;
2887 }
2888 }
2889 EXPORT_SYMBOL(proto_unregister);
2890
2891 #ifdef CONFIG_PROC_FS
2892 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2893 __acquires(proto_list_mutex)
2894 {
2895 mutex_lock(&proto_list_mutex);
2896 return seq_list_start_head(&proto_list, *pos);
2897 }
2898
2899 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2900 {
2901 return seq_list_next(v, &proto_list, pos);
2902 }
2903
2904 static void proto_seq_stop(struct seq_file *seq, void *v)
2905 __releases(proto_list_mutex)
2906 {
2907 mutex_unlock(&proto_list_mutex);
2908 }
2909
2910 static char proto_method_implemented(const void *method)
2911 {
2912 return method == NULL ? 'n' : 'y';
2913 }
2914 static long sock_prot_memory_allocated(struct proto *proto)
2915 {
2916 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2917 }
2918
2919 static char *sock_prot_memory_pressure(struct proto *proto)
2920 {
2921 return proto->memory_pressure != NULL ?
2922 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2923 }
2924
2925 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2926 {
2927
2928 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2929 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2930 proto->name,
2931 proto->obj_size,
2932 sock_prot_inuse_get(seq_file_net(seq), proto),
2933 sock_prot_memory_allocated(proto),
2934 sock_prot_memory_pressure(proto),
2935 proto->max_header,
2936 proto->slab == NULL ? "no" : "yes",
2937 module_name(proto->owner),
2938 proto_method_implemented(proto->close),
2939 proto_method_implemented(proto->connect),
2940 proto_method_implemented(proto->disconnect),
2941 proto_method_implemented(proto->accept),
2942 proto_method_implemented(proto->ioctl),
2943 proto_method_implemented(proto->init),
2944 proto_method_implemented(proto->destroy),
2945 proto_method_implemented(proto->shutdown),
2946 proto_method_implemented(proto->setsockopt),
2947 proto_method_implemented(proto->getsockopt),
2948 proto_method_implemented(proto->sendmsg),
2949 proto_method_implemented(proto->recvmsg),
2950 proto_method_implemented(proto->sendpage),
2951 proto_method_implemented(proto->bind),
2952 proto_method_implemented(proto->backlog_rcv),
2953 proto_method_implemented(proto->hash),
2954 proto_method_implemented(proto->unhash),
2955 proto_method_implemented(proto->get_port),
2956 proto_method_implemented(proto->enter_memory_pressure));
2957 }
2958
2959 static int proto_seq_show(struct seq_file *seq, void *v)
2960 {
2961 if (v == &proto_list)
2962 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2963 "protocol",
2964 "size",
2965 "sockets",
2966 "memory",
2967 "press",
2968 "maxhdr",
2969 "slab",
2970 "module",
2971 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2972 else
2973 proto_seq_printf(seq, list_entry(v, struct proto, node));
2974 return 0;
2975 }
2976
2977 static const struct seq_operations proto_seq_ops = {
2978 .start = proto_seq_start,
2979 .next = proto_seq_next,
2980 .stop = proto_seq_stop,
2981 .show = proto_seq_show,
2982 };
2983
2984 static int proto_seq_open(struct inode *inode, struct file *file)
2985 {
2986 return seq_open_net(inode, file, &proto_seq_ops,
2987 sizeof(struct seq_net_private));
2988 }
2989
2990 static const struct file_operations proto_seq_fops = {
2991 .owner = THIS_MODULE,
2992 .open = proto_seq_open,
2993 .read = seq_read,
2994 .llseek = seq_lseek,
2995 .release = seq_release_net,
2996 };
2997
2998 static __net_init int proto_init_net(struct net *net)
2999 {
3000 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3001 return -ENOMEM;
3002
3003 return 0;
3004 }
3005
3006 static __net_exit void proto_exit_net(struct net *net)
3007 {
3008 remove_proc_entry("protocols", net->proc_net);
3009 }
3010
3011
3012 static __net_initdata struct pernet_operations proto_net_ops = {
3013 .init = proto_init_net,
3014 .exit = proto_exit_net,
3015 };
3016
3017 static int __init proto_init(void)
3018 {
3019 return register_pernet_subsys(&proto_net_ops);
3020 }
3021
3022 subsys_initcall(proto_init);
3023
3024 #endif /* PROC_FS */
Linux kernel - Deliverables
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