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