powerpc: Add new kconfig CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
[linux/fpc-iii.git] / net / core / sock.c
blobc0b5b2f17412ec3ac3d4b1cf400fb2fbcabf086f
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.
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
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>
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
83 * To Fix:
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.
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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/sched/mm.h>
106 #include <linux/timer.h>
107 #include <linux/string.h>
108 #include <linux/sockios.h>
109 #include <linux/net.h>
110 #include <linux/mm.h>
111 #include <linux/slab.h>
112 #include <linux/interrupt.h>
113 #include <linux/poll.h>
114 #include <linux/tcp.h>
115 #include <linux/init.h>
116 #include <linux/highmem.h>
117 #include <linux/user_namespace.h>
118 #include <linux/static_key.h>
119 #include <linux/memcontrol.h>
120 #include <linux/prefetch.h>
122 #include <linux/uaccess.h>
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <net/net_namespace.h>
128 #include <net/request_sock.h>
129 #include <net/sock.h>
130 #include <linux/net_tstamp.h>
131 #include <net/xfrm.h>
132 #include <linux/ipsec.h>
133 #include <net/cls_cgroup.h>
134 #include <net/netprio_cgroup.h>
135 #include <linux/sock_diag.h>
137 #include <linux/filter.h>
138 #include <net/sock_reuseport.h>
140 #include <trace/events/sock.h>
142 #include <net/tcp.h>
143 #include <net/busy_poll.h>
145 static DEFINE_MUTEX(proto_list_mutex);
146 static LIST_HEAD(proto_list);
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
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.
158 bool sk_ns_capable(const struct sock *sk,
159 struct user_namespace *user_ns, int cap)
161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
162 ns_capable(user_ns, cap);
164 EXPORT_SYMBOL(sk_ns_capable);
167 * sk_capable - Socket global capability test
168 * @sk: Socket to use a capability on or through
169 * @cap: The global capability to use
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.
175 bool sk_capable(const struct sock *sk, int cap)
177 return sk_ns_capable(sk, &init_user_ns, cap);
179 EXPORT_SYMBOL(sk_capable);
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
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.
190 bool sk_net_capable(const struct sock *sk, int cap)
192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
194 EXPORT_SYMBOL(sk_net_capable);
197 * Each address family might have different locking rules, so we have
198 * one slock key per address family and separate keys for internal and
199 * userspace sockets.
201 static struct lock_class_key af_family_keys[AF_MAX];
202 static struct lock_class_key af_family_kern_keys[AF_MAX];
203 static struct lock_class_key af_family_slock_keys[AF_MAX];
204 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
207 * Make lock validator output more readable. (we pre-construct these
208 * strings build-time, so that runtime initialization of socket
209 * locks is fast):
212 #define _sock_locks(x) \
213 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
214 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
215 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
216 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
217 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
218 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
219 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
220 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
221 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
222 x "27" , x "28" , x "AF_CAN" , \
223 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
224 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
225 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
226 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
227 x "AF_QIPCRTR", x "AF_SMC" , x "AF_MAX"
229 static const char *const af_family_key_strings[AF_MAX+1] = {
230 _sock_locks("sk_lock-")
232 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
233 _sock_locks("slock-")
235 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
236 _sock_locks("clock-")
239 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
240 _sock_locks("k-sk_lock-")
242 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
243 _sock_locks("k-slock-")
245 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
246 _sock_locks("k-clock-")
248 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
249 "rlock-AF_UNSPEC", "rlock-AF_UNIX" , "rlock-AF_INET" ,
250 "rlock-AF_AX25" , "rlock-AF_IPX" , "rlock-AF_APPLETALK",
251 "rlock-AF_NETROM", "rlock-AF_BRIDGE" , "rlock-AF_ATMPVC" ,
252 "rlock-AF_X25" , "rlock-AF_INET6" , "rlock-AF_ROSE" ,
253 "rlock-AF_DECnet", "rlock-AF_NETBEUI" , "rlock-AF_SECURITY" ,
254 "rlock-AF_KEY" , "rlock-AF_NETLINK" , "rlock-AF_PACKET" ,
255 "rlock-AF_ASH" , "rlock-AF_ECONET" , "rlock-AF_ATMSVC" ,
256 "rlock-AF_RDS" , "rlock-AF_SNA" , "rlock-AF_IRDA" ,
257 "rlock-AF_PPPOX" , "rlock-AF_WANPIPE" , "rlock-AF_LLC" ,
258 "rlock-27" , "rlock-28" , "rlock-AF_CAN" ,
259 "rlock-AF_TIPC" , "rlock-AF_BLUETOOTH", "rlock-AF_IUCV" ,
260 "rlock-AF_RXRPC" , "rlock-AF_ISDN" , "rlock-AF_PHONET" ,
261 "rlock-AF_IEEE802154", "rlock-AF_CAIF" , "rlock-AF_ALG" ,
262 "rlock-AF_NFC" , "rlock-AF_VSOCK" , "rlock-AF_KCM" ,
263 "rlock-AF_QIPCRTR", "rlock-AF_SMC" , "rlock-AF_MAX"
265 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
266 "wlock-AF_UNSPEC", "wlock-AF_UNIX" , "wlock-AF_INET" ,
267 "wlock-AF_AX25" , "wlock-AF_IPX" , "wlock-AF_APPLETALK",
268 "wlock-AF_NETROM", "wlock-AF_BRIDGE" , "wlock-AF_ATMPVC" ,
269 "wlock-AF_X25" , "wlock-AF_INET6" , "wlock-AF_ROSE" ,
270 "wlock-AF_DECnet", "wlock-AF_NETBEUI" , "wlock-AF_SECURITY" ,
271 "wlock-AF_KEY" , "wlock-AF_NETLINK" , "wlock-AF_PACKET" ,
272 "wlock-AF_ASH" , "wlock-AF_ECONET" , "wlock-AF_ATMSVC" ,
273 "wlock-AF_RDS" , "wlock-AF_SNA" , "wlock-AF_IRDA" ,
274 "wlock-AF_PPPOX" , "wlock-AF_WANPIPE" , "wlock-AF_LLC" ,
275 "wlock-27" , "wlock-28" , "wlock-AF_CAN" ,
276 "wlock-AF_TIPC" , "wlock-AF_BLUETOOTH", "wlock-AF_IUCV" ,
277 "wlock-AF_RXRPC" , "wlock-AF_ISDN" , "wlock-AF_PHONET" ,
278 "wlock-AF_IEEE802154", "wlock-AF_CAIF" , "wlock-AF_ALG" ,
279 "wlock-AF_NFC" , "wlock-AF_VSOCK" , "wlock-AF_KCM" ,
280 "wlock-AF_QIPCRTR", "wlock-AF_SMC" , "wlock-AF_MAX"
282 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
283 "elock-AF_UNSPEC", "elock-AF_UNIX" , "elock-AF_INET" ,
284 "elock-AF_AX25" , "elock-AF_IPX" , "elock-AF_APPLETALK",
285 "elock-AF_NETROM", "elock-AF_BRIDGE" , "elock-AF_ATMPVC" ,
286 "elock-AF_X25" , "elock-AF_INET6" , "elock-AF_ROSE" ,
287 "elock-AF_DECnet", "elock-AF_NETBEUI" , "elock-AF_SECURITY" ,
288 "elock-AF_KEY" , "elock-AF_NETLINK" , "elock-AF_PACKET" ,
289 "elock-AF_ASH" , "elock-AF_ECONET" , "elock-AF_ATMSVC" ,
290 "elock-AF_RDS" , "elock-AF_SNA" , "elock-AF_IRDA" ,
291 "elock-AF_PPPOX" , "elock-AF_WANPIPE" , "elock-AF_LLC" ,
292 "elock-27" , "elock-28" , "elock-AF_CAN" ,
293 "elock-AF_TIPC" , "elock-AF_BLUETOOTH", "elock-AF_IUCV" ,
294 "elock-AF_RXRPC" , "elock-AF_ISDN" , "elock-AF_PHONET" ,
295 "elock-AF_IEEE802154", "elock-AF_CAIF" , "elock-AF_ALG" ,
296 "elock-AF_NFC" , "elock-AF_VSOCK" , "elock-AF_KCM" ,
297 "elock-AF_QIPCRTR", "elock-AF_SMC" , "elock-AF_MAX"
301 * sk_callback_lock and sk queues locking rules are per-address-family,
302 * so split the lock classes by using a per-AF key:
304 static struct lock_class_key af_callback_keys[AF_MAX];
305 static struct lock_class_key af_rlock_keys[AF_MAX];
306 static struct lock_class_key af_wlock_keys[AF_MAX];
307 static struct lock_class_key af_elock_keys[AF_MAX];
308 static struct lock_class_key af_kern_callback_keys[AF_MAX];
310 /* Run time adjustable parameters. */
311 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
312 EXPORT_SYMBOL(sysctl_wmem_max);
313 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
314 EXPORT_SYMBOL(sysctl_rmem_max);
315 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
316 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
318 /* Maximal space eaten by iovec or ancillary data plus some space */
319 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
320 EXPORT_SYMBOL(sysctl_optmem_max);
322 int sysctl_tstamp_allow_data __read_mostly = 1;
324 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
325 EXPORT_SYMBOL_GPL(memalloc_socks);
328 * sk_set_memalloc - sets %SOCK_MEMALLOC
329 * @sk: socket to set it on
331 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
332 * It's the responsibility of the admin to adjust min_free_kbytes
333 * to meet the requirements
335 void sk_set_memalloc(struct sock *sk)
337 sock_set_flag(sk, SOCK_MEMALLOC);
338 sk->sk_allocation |= __GFP_MEMALLOC;
339 static_key_slow_inc(&memalloc_socks);
341 EXPORT_SYMBOL_GPL(sk_set_memalloc);
343 void sk_clear_memalloc(struct sock *sk)
345 sock_reset_flag(sk, SOCK_MEMALLOC);
346 sk->sk_allocation &= ~__GFP_MEMALLOC;
347 static_key_slow_dec(&memalloc_socks);
350 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
351 * progress of swapping. SOCK_MEMALLOC may be cleared while
352 * it has rmem allocations due to the last swapfile being deactivated
353 * but there is a risk that the socket is unusable due to exceeding
354 * the rmem limits. Reclaim the reserves and obey rmem limits again.
356 sk_mem_reclaim(sk);
358 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
360 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
362 int ret;
363 unsigned int noreclaim_flag;
365 /* these should have been dropped before queueing */
366 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
368 noreclaim_flag = memalloc_noreclaim_save();
369 ret = sk->sk_backlog_rcv(sk, skb);
370 memalloc_noreclaim_restore(noreclaim_flag);
372 return ret;
374 EXPORT_SYMBOL(__sk_backlog_rcv);
376 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
378 struct timeval tv;
380 if (optlen < sizeof(tv))
381 return -EINVAL;
382 if (copy_from_user(&tv, optval, sizeof(tv)))
383 return -EFAULT;
384 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
385 return -EDOM;
387 if (tv.tv_sec < 0) {
388 static int warned __read_mostly;
390 *timeo_p = 0;
391 if (warned < 10 && net_ratelimit()) {
392 warned++;
393 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
394 __func__, current->comm, task_pid_nr(current));
396 return 0;
398 *timeo_p = MAX_SCHEDULE_TIMEOUT;
399 if (tv.tv_sec == 0 && tv.tv_usec == 0)
400 return 0;
401 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
402 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ);
403 return 0;
406 static void sock_warn_obsolete_bsdism(const char *name)
408 static int warned;
409 static char warncomm[TASK_COMM_LEN];
410 if (strcmp(warncomm, current->comm) && warned < 5) {
411 strcpy(warncomm, current->comm);
412 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
413 warncomm, name);
414 warned++;
418 static bool sock_needs_netstamp(const struct sock *sk)
420 switch (sk->sk_family) {
421 case AF_UNSPEC:
422 case AF_UNIX:
423 return false;
424 default:
425 return true;
429 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
431 if (sk->sk_flags & flags) {
432 sk->sk_flags &= ~flags;
433 if (sock_needs_netstamp(sk) &&
434 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
435 net_disable_timestamp();
440 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
442 unsigned long flags;
443 struct sk_buff_head *list = &sk->sk_receive_queue;
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;
451 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
452 atomic_inc(&sk->sk_drops);
453 return -ENOBUFS;
456 skb->dev = NULL;
457 skb_set_owner_r(skb, sk);
459 /* we escape from rcu protected region, make sure we dont leak
460 * a norefcounted dst
462 skb_dst_force(skb);
464 spin_lock_irqsave(&list->lock, flags);
465 sock_skb_set_dropcount(sk, skb);
466 __skb_queue_tail(list, skb);
467 spin_unlock_irqrestore(&list->lock, flags);
469 if (!sock_flag(sk, SOCK_DEAD))
470 sk->sk_data_ready(sk);
471 return 0;
473 EXPORT_SYMBOL(__sock_queue_rcv_skb);
475 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 int err;
479 err = sk_filter(sk, skb);
480 if (err)
481 return err;
483 return __sock_queue_rcv_skb(sk, skb);
485 EXPORT_SYMBOL(sock_queue_rcv_skb);
487 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
488 const int nested, unsigned int trim_cap, bool refcounted)
490 int rc = NET_RX_SUCCESS;
492 if (sk_filter_trim_cap(sk, skb, trim_cap))
493 goto discard_and_relse;
495 skb->dev = NULL;
497 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
498 atomic_inc(&sk->sk_drops);
499 goto discard_and_relse;
501 if (nested)
502 bh_lock_sock_nested(sk);
503 else
504 bh_lock_sock(sk);
505 if (!sock_owned_by_user(sk)) {
507 * trylock + unlock semantics:
509 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
511 rc = sk_backlog_rcv(sk, skb);
513 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
514 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
515 bh_unlock_sock(sk);
516 atomic_inc(&sk->sk_drops);
517 goto discard_and_relse;
520 bh_unlock_sock(sk);
521 out:
522 if (refcounted)
523 sock_put(sk);
524 return rc;
525 discard_and_relse:
526 kfree_skb(skb);
527 goto out;
529 EXPORT_SYMBOL(__sk_receive_skb);
531 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
533 struct dst_entry *dst = __sk_dst_get(sk);
535 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
536 sk_tx_queue_clear(sk);
537 sk->sk_dst_pending_confirm = 0;
538 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
539 dst_release(dst);
540 return NULL;
543 return dst;
545 EXPORT_SYMBOL(__sk_dst_check);
547 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
549 struct dst_entry *dst = sk_dst_get(sk);
551 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
552 sk_dst_reset(sk);
553 dst_release(dst);
554 return NULL;
557 return dst;
559 EXPORT_SYMBOL(sk_dst_check);
561 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
562 int optlen)
564 int ret = -ENOPROTOOPT;
565 #ifdef CONFIG_NETDEVICES
566 struct net *net = sock_net(sk);
567 char devname[IFNAMSIZ];
568 int index;
570 /* Sorry... */
571 ret = -EPERM;
572 if (!ns_capable(net->user_ns, CAP_NET_RAW))
573 goto out;
575 ret = -EINVAL;
576 if (optlen < 0)
577 goto out;
579 /* Bind this socket to a particular device like "eth0",
580 * as specified in the passed interface name. If the
581 * name is "" or the option length is zero the socket
582 * is not bound.
584 if (optlen > IFNAMSIZ - 1)
585 optlen = IFNAMSIZ - 1;
586 memset(devname, 0, sizeof(devname));
588 ret = -EFAULT;
589 if (copy_from_user(devname, optval, optlen))
590 goto out;
592 index = 0;
593 if (devname[0] != '\0') {
594 struct net_device *dev;
596 rcu_read_lock();
597 dev = dev_get_by_name_rcu(net, devname);
598 if (dev)
599 index = dev->ifindex;
600 rcu_read_unlock();
601 ret = -ENODEV;
602 if (!dev)
603 goto out;
606 lock_sock(sk);
607 sk->sk_bound_dev_if = index;
608 sk_dst_reset(sk);
609 release_sock(sk);
611 ret = 0;
613 out:
614 #endif
616 return ret;
619 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
620 int __user *optlen, int len)
622 int ret = -ENOPROTOOPT;
623 #ifdef CONFIG_NETDEVICES
624 struct net *net = sock_net(sk);
625 char devname[IFNAMSIZ];
627 if (sk->sk_bound_dev_if == 0) {
628 len = 0;
629 goto zero;
632 ret = -EINVAL;
633 if (len < IFNAMSIZ)
634 goto out;
636 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
637 if (ret)
638 goto out;
640 len = strlen(devname) + 1;
642 ret = -EFAULT;
643 if (copy_to_user(optval, devname, len))
644 goto out;
646 zero:
647 ret = -EFAULT;
648 if (put_user(len, optlen))
649 goto out;
651 ret = 0;
653 out:
654 #endif
656 return ret;
659 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
661 if (valbool)
662 sock_set_flag(sk, bit);
663 else
664 sock_reset_flag(sk, bit);
667 bool sk_mc_loop(struct sock *sk)
669 if (dev_recursion_level())
670 return false;
671 if (!sk)
672 return true;
673 switch (sk->sk_family) {
674 case AF_INET:
675 return inet_sk(sk)->mc_loop;
676 #if IS_ENABLED(CONFIG_IPV6)
677 case AF_INET6:
678 return inet6_sk(sk)->mc_loop;
679 #endif
681 WARN_ON(1);
682 return true;
684 EXPORT_SYMBOL(sk_mc_loop);
687 * This is meant for all protocols to use and covers goings on
688 * at the socket level. Everything here is generic.
691 int sock_setsockopt(struct socket *sock, int level, int optname,
692 char __user *optval, unsigned int optlen)
694 struct sock *sk = sock->sk;
695 int val;
696 int valbool;
697 struct linger ling;
698 int ret = 0;
701 * Options without arguments
704 if (optname == SO_BINDTODEVICE)
705 return sock_setbindtodevice(sk, optval, optlen);
707 if (optlen < sizeof(int))
708 return -EINVAL;
710 if (get_user(val, (int __user *)optval))
711 return -EFAULT;
713 valbool = val ? 1 : 0;
715 lock_sock(sk);
717 switch (optname) {
718 case SO_DEBUG:
719 if (val && !capable(CAP_NET_ADMIN))
720 ret = -EACCES;
721 else
722 sock_valbool_flag(sk, SOCK_DBG, valbool);
723 break;
724 case SO_REUSEADDR:
725 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
726 break;
727 case SO_REUSEPORT:
728 sk->sk_reuseport = valbool;
729 break;
730 case SO_TYPE:
731 case SO_PROTOCOL:
732 case SO_DOMAIN:
733 case SO_ERROR:
734 ret = -ENOPROTOOPT;
735 break;
736 case SO_DONTROUTE:
737 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
738 break;
739 case SO_BROADCAST:
740 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
741 break;
742 case SO_SNDBUF:
743 /* Don't error on this BSD doesn't and if you think
744 * about it this is right. Otherwise apps have to
745 * play 'guess the biggest size' games. RCVBUF/SNDBUF
746 * are treated in BSD as hints
748 val = min_t(u32, val, sysctl_wmem_max);
749 set_sndbuf:
750 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
751 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
752 /* Wake up sending tasks if we upped the value. */
753 sk->sk_write_space(sk);
754 break;
756 case SO_SNDBUFFORCE:
757 if (!capable(CAP_NET_ADMIN)) {
758 ret = -EPERM;
759 break;
761 goto set_sndbuf;
763 case SO_RCVBUF:
764 /* Don't error on this BSD doesn't and if you think
765 * about it this is right. Otherwise apps have to
766 * play 'guess the biggest size' games. RCVBUF/SNDBUF
767 * are treated in BSD as hints
769 val = min_t(u32, val, sysctl_rmem_max);
770 set_rcvbuf:
771 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
773 * We double it on the way in to account for
774 * "struct sk_buff" etc. overhead. Applications
775 * assume that the SO_RCVBUF setting they make will
776 * allow that much actual data to be received on that
777 * socket.
779 * Applications are unaware that "struct sk_buff" and
780 * other overheads allocate from the receive buffer
781 * during socket buffer allocation.
783 * And after considering the possible alternatives,
784 * returning the value we actually used in getsockopt
785 * is the most desirable behavior.
787 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
788 break;
790 case SO_RCVBUFFORCE:
791 if (!capable(CAP_NET_ADMIN)) {
792 ret = -EPERM;
793 break;
795 goto set_rcvbuf;
797 case SO_KEEPALIVE:
798 if (sk->sk_prot->keepalive)
799 sk->sk_prot->keepalive(sk, valbool);
800 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
801 break;
803 case SO_OOBINLINE:
804 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
805 break;
807 case SO_NO_CHECK:
808 sk->sk_no_check_tx = valbool;
809 break;
811 case SO_PRIORITY:
812 if ((val >= 0 && val <= 6) ||
813 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
814 sk->sk_priority = val;
815 else
816 ret = -EPERM;
817 break;
819 case SO_LINGER:
820 if (optlen < sizeof(ling)) {
821 ret = -EINVAL; /* 1003.1g */
822 break;
824 if (copy_from_user(&ling, optval, sizeof(ling))) {
825 ret = -EFAULT;
826 break;
828 if (!ling.l_onoff)
829 sock_reset_flag(sk, SOCK_LINGER);
830 else {
831 #if (BITS_PER_LONG == 32)
832 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
833 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
834 else
835 #endif
836 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
837 sock_set_flag(sk, SOCK_LINGER);
839 break;
841 case SO_BSDCOMPAT:
842 sock_warn_obsolete_bsdism("setsockopt");
843 break;
845 case SO_PASSCRED:
846 if (valbool)
847 set_bit(SOCK_PASSCRED, &sock->flags);
848 else
849 clear_bit(SOCK_PASSCRED, &sock->flags);
850 break;
852 case SO_TIMESTAMP:
853 case SO_TIMESTAMPNS:
854 if (valbool) {
855 if (optname == SO_TIMESTAMP)
856 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
857 else
858 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
859 sock_set_flag(sk, SOCK_RCVTSTAMP);
860 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
861 } else {
862 sock_reset_flag(sk, SOCK_RCVTSTAMP);
863 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
865 break;
867 case SO_TIMESTAMPING:
868 if (val & ~SOF_TIMESTAMPING_MASK) {
869 ret = -EINVAL;
870 break;
873 if (val & SOF_TIMESTAMPING_OPT_ID &&
874 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
875 if (sk->sk_protocol == IPPROTO_TCP &&
876 sk->sk_type == SOCK_STREAM) {
877 if ((1 << sk->sk_state) &
878 (TCPF_CLOSE | TCPF_LISTEN)) {
879 ret = -EINVAL;
880 break;
882 sk->sk_tskey = tcp_sk(sk)->snd_una;
883 } else {
884 sk->sk_tskey = 0;
888 if (val & SOF_TIMESTAMPING_OPT_STATS &&
889 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
890 ret = -EINVAL;
891 break;
894 sk->sk_tsflags = val;
895 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
896 sock_enable_timestamp(sk,
897 SOCK_TIMESTAMPING_RX_SOFTWARE);
898 else
899 sock_disable_timestamp(sk,
900 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
901 break;
903 case SO_RCVLOWAT:
904 if (val < 0)
905 val = INT_MAX;
906 sk->sk_rcvlowat = val ? : 1;
907 break;
909 case SO_RCVTIMEO:
910 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
911 break;
913 case SO_SNDTIMEO:
914 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
915 break;
917 case SO_ATTACH_FILTER:
918 ret = -EINVAL;
919 if (optlen == sizeof(struct sock_fprog)) {
920 struct sock_fprog fprog;
922 ret = -EFAULT;
923 if (copy_from_user(&fprog, optval, sizeof(fprog)))
924 break;
926 ret = sk_attach_filter(&fprog, sk);
928 break;
930 case SO_ATTACH_BPF:
931 ret = -EINVAL;
932 if (optlen == sizeof(u32)) {
933 u32 ufd;
935 ret = -EFAULT;
936 if (copy_from_user(&ufd, optval, sizeof(ufd)))
937 break;
939 ret = sk_attach_bpf(ufd, sk);
941 break;
943 case SO_ATTACH_REUSEPORT_CBPF:
944 ret = -EINVAL;
945 if (optlen == sizeof(struct sock_fprog)) {
946 struct sock_fprog fprog;
948 ret = -EFAULT;
949 if (copy_from_user(&fprog, optval, sizeof(fprog)))
950 break;
952 ret = sk_reuseport_attach_filter(&fprog, sk);
954 break;
956 case SO_ATTACH_REUSEPORT_EBPF:
957 ret = -EINVAL;
958 if (optlen == sizeof(u32)) {
959 u32 ufd;
961 ret = -EFAULT;
962 if (copy_from_user(&ufd, optval, sizeof(ufd)))
963 break;
965 ret = sk_reuseport_attach_bpf(ufd, sk);
967 break;
969 case SO_DETACH_FILTER:
970 ret = sk_detach_filter(sk);
971 break;
973 case SO_LOCK_FILTER:
974 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
975 ret = -EPERM;
976 else
977 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
978 break;
980 case SO_PASSSEC:
981 if (valbool)
982 set_bit(SOCK_PASSSEC, &sock->flags);
983 else
984 clear_bit(SOCK_PASSSEC, &sock->flags);
985 break;
986 case SO_MARK:
987 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
988 ret = -EPERM;
989 else
990 sk->sk_mark = val;
991 break;
993 case SO_RXQ_OVFL:
994 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
995 break;
997 case SO_WIFI_STATUS:
998 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
999 break;
1001 case SO_PEEK_OFF:
1002 if (sock->ops->set_peek_off)
1003 ret = sock->ops->set_peek_off(sk, val);
1004 else
1005 ret = -EOPNOTSUPP;
1006 break;
1008 case SO_NOFCS:
1009 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1010 break;
1012 case SO_SELECT_ERR_QUEUE:
1013 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1014 break;
1016 #ifdef CONFIG_NET_RX_BUSY_POLL
1017 case SO_BUSY_POLL:
1018 /* allow unprivileged users to decrease the value */
1019 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1020 ret = -EPERM;
1021 else {
1022 if (val < 0)
1023 ret = -EINVAL;
1024 else
1025 sk->sk_ll_usec = val;
1027 break;
1028 #endif
1030 case SO_MAX_PACING_RATE:
1031 if (val != ~0U)
1032 cmpxchg(&sk->sk_pacing_status,
1033 SK_PACING_NONE,
1034 SK_PACING_NEEDED);
1035 sk->sk_max_pacing_rate = val;
1036 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1037 sk->sk_max_pacing_rate);
1038 break;
1040 case SO_INCOMING_CPU:
1041 sk->sk_incoming_cpu = val;
1042 break;
1044 case SO_CNX_ADVICE:
1045 if (val == 1)
1046 dst_negative_advice(sk);
1047 break;
1049 case SO_ZEROCOPY:
1050 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
1051 ret = -ENOTSUPP;
1052 else if (sk->sk_protocol != IPPROTO_TCP)
1053 ret = -ENOTSUPP;
1054 else if (sk->sk_state != TCP_CLOSE)
1055 ret = -EBUSY;
1056 else if (val < 0 || val > 1)
1057 ret = -EINVAL;
1058 else
1059 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1060 break;
1062 default:
1063 ret = -ENOPROTOOPT;
1064 break;
1066 release_sock(sk);
1067 return ret;
1069 EXPORT_SYMBOL(sock_setsockopt);
1072 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1073 struct ucred *ucred)
1075 ucred->pid = pid_vnr(pid);
1076 ucred->uid = ucred->gid = -1;
1077 if (cred) {
1078 struct user_namespace *current_ns = current_user_ns();
1080 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1081 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1085 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1087 struct user_namespace *user_ns = current_user_ns();
1088 int i;
1090 for (i = 0; i < src->ngroups; i++)
1091 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1092 return -EFAULT;
1094 return 0;
1097 int sock_getsockopt(struct socket *sock, int level, int optname,
1098 char __user *optval, int __user *optlen)
1100 struct sock *sk = sock->sk;
1102 union {
1103 int val;
1104 u64 val64;
1105 struct linger ling;
1106 struct timeval tm;
1107 } v;
1109 int lv = sizeof(int);
1110 int len;
1112 if (get_user(len, optlen))
1113 return -EFAULT;
1114 if (len < 0)
1115 return -EINVAL;
1117 memset(&v, 0, sizeof(v));
1119 switch (optname) {
1120 case SO_DEBUG:
1121 v.val = sock_flag(sk, SOCK_DBG);
1122 break;
1124 case SO_DONTROUTE:
1125 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1126 break;
1128 case SO_BROADCAST:
1129 v.val = sock_flag(sk, SOCK_BROADCAST);
1130 break;
1132 case SO_SNDBUF:
1133 v.val = sk->sk_sndbuf;
1134 break;
1136 case SO_RCVBUF:
1137 v.val = sk->sk_rcvbuf;
1138 break;
1140 case SO_REUSEADDR:
1141 v.val = sk->sk_reuse;
1142 break;
1144 case SO_REUSEPORT:
1145 v.val = sk->sk_reuseport;
1146 break;
1148 case SO_KEEPALIVE:
1149 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1150 break;
1152 case SO_TYPE:
1153 v.val = sk->sk_type;
1154 break;
1156 case SO_PROTOCOL:
1157 v.val = sk->sk_protocol;
1158 break;
1160 case SO_DOMAIN:
1161 v.val = sk->sk_family;
1162 break;
1164 case SO_ERROR:
1165 v.val = -sock_error(sk);
1166 if (v.val == 0)
1167 v.val = xchg(&sk->sk_err_soft, 0);
1168 break;
1170 case SO_OOBINLINE:
1171 v.val = sock_flag(sk, SOCK_URGINLINE);
1172 break;
1174 case SO_NO_CHECK:
1175 v.val = sk->sk_no_check_tx;
1176 break;
1178 case SO_PRIORITY:
1179 v.val = sk->sk_priority;
1180 break;
1182 case SO_LINGER:
1183 lv = sizeof(v.ling);
1184 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1185 v.ling.l_linger = sk->sk_lingertime / HZ;
1186 break;
1188 case SO_BSDCOMPAT:
1189 sock_warn_obsolete_bsdism("getsockopt");
1190 break;
1192 case SO_TIMESTAMP:
1193 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1194 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1195 break;
1197 case SO_TIMESTAMPNS:
1198 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1199 break;
1201 case SO_TIMESTAMPING:
1202 v.val = sk->sk_tsflags;
1203 break;
1205 case SO_RCVTIMEO:
1206 lv = sizeof(struct timeval);
1207 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1208 v.tm.tv_sec = 0;
1209 v.tm.tv_usec = 0;
1210 } else {
1211 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1212 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
1214 break;
1216 case SO_SNDTIMEO:
1217 lv = sizeof(struct timeval);
1218 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1219 v.tm.tv_sec = 0;
1220 v.tm.tv_usec = 0;
1221 } else {
1222 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1223 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1225 break;
1227 case SO_RCVLOWAT:
1228 v.val = sk->sk_rcvlowat;
1229 break;
1231 case SO_SNDLOWAT:
1232 v.val = 1;
1233 break;
1235 case SO_PASSCRED:
1236 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1237 break;
1239 case SO_PEERCRED:
1241 struct ucred peercred;
1242 if (len > sizeof(peercred))
1243 len = sizeof(peercred);
1244 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1245 if (copy_to_user(optval, &peercred, len))
1246 return -EFAULT;
1247 goto lenout;
1250 case SO_PEERGROUPS:
1252 int ret, n;
1254 if (!sk->sk_peer_cred)
1255 return -ENODATA;
1257 n = sk->sk_peer_cred->group_info->ngroups;
1258 if (len < n * sizeof(gid_t)) {
1259 len = n * sizeof(gid_t);
1260 return put_user(len, optlen) ? -EFAULT : -ERANGE;
1262 len = n * sizeof(gid_t);
1264 ret = groups_to_user((gid_t __user *)optval,
1265 sk->sk_peer_cred->group_info);
1266 if (ret)
1267 return ret;
1268 goto lenout;
1271 case SO_PEERNAME:
1273 char address[128];
1275 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1276 return -ENOTCONN;
1277 if (lv < len)
1278 return -EINVAL;
1279 if (copy_to_user(optval, address, len))
1280 return -EFAULT;
1281 goto lenout;
1284 /* Dubious BSD thing... Probably nobody even uses it, but
1285 * the UNIX standard wants it for whatever reason... -DaveM
1287 case SO_ACCEPTCONN:
1288 v.val = sk->sk_state == TCP_LISTEN;
1289 break;
1291 case SO_PASSSEC:
1292 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1293 break;
1295 case SO_PEERSEC:
1296 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1298 case SO_MARK:
1299 v.val = sk->sk_mark;
1300 break;
1302 case SO_RXQ_OVFL:
1303 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1304 break;
1306 case SO_WIFI_STATUS:
1307 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1308 break;
1310 case SO_PEEK_OFF:
1311 if (!sock->ops->set_peek_off)
1312 return -EOPNOTSUPP;
1314 v.val = sk->sk_peek_off;
1315 break;
1316 case SO_NOFCS:
1317 v.val = sock_flag(sk, SOCK_NOFCS);
1318 break;
1320 case SO_BINDTODEVICE:
1321 return sock_getbindtodevice(sk, optval, optlen, len);
1323 case SO_GET_FILTER:
1324 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1325 if (len < 0)
1326 return len;
1328 goto lenout;
1330 case SO_LOCK_FILTER:
1331 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1332 break;
1334 case SO_BPF_EXTENSIONS:
1335 v.val = bpf_tell_extensions();
1336 break;
1338 case SO_SELECT_ERR_QUEUE:
1339 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1340 break;
1342 #ifdef CONFIG_NET_RX_BUSY_POLL
1343 case SO_BUSY_POLL:
1344 v.val = sk->sk_ll_usec;
1345 break;
1346 #endif
1348 case SO_MAX_PACING_RATE:
1349 v.val = sk->sk_max_pacing_rate;
1350 break;
1352 case SO_INCOMING_CPU:
1353 v.val = sk->sk_incoming_cpu;
1354 break;
1356 case SO_MEMINFO:
1358 u32 meminfo[SK_MEMINFO_VARS];
1360 if (get_user(len, optlen))
1361 return -EFAULT;
1363 sk_get_meminfo(sk, meminfo);
1365 len = min_t(unsigned int, len, sizeof(meminfo));
1366 if (copy_to_user(optval, &meminfo, len))
1367 return -EFAULT;
1369 goto lenout;
1372 #ifdef CONFIG_NET_RX_BUSY_POLL
1373 case SO_INCOMING_NAPI_ID:
1374 v.val = READ_ONCE(sk->sk_napi_id);
1376 /* aggregate non-NAPI IDs down to 0 */
1377 if (v.val < MIN_NAPI_ID)
1378 v.val = 0;
1380 break;
1381 #endif
1383 case SO_COOKIE:
1384 lv = sizeof(u64);
1385 if (len < lv)
1386 return -EINVAL;
1387 v.val64 = sock_gen_cookie(sk);
1388 break;
1390 case SO_ZEROCOPY:
1391 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1392 break;
1394 default:
1395 /* We implement the SO_SNDLOWAT etc to not be settable
1396 * (1003.1g 7).
1398 return -ENOPROTOOPT;
1401 if (len > lv)
1402 len = lv;
1403 if (copy_to_user(optval, &v, len))
1404 return -EFAULT;
1405 lenout:
1406 if (put_user(len, optlen))
1407 return -EFAULT;
1408 return 0;
1412 * Initialize an sk_lock.
1414 * (We also register the sk_lock with the lock validator.)
1416 static inline void sock_lock_init(struct sock *sk)
1418 if (sk->sk_kern_sock)
1419 sock_lock_init_class_and_name(
1421 af_family_kern_slock_key_strings[sk->sk_family],
1422 af_family_kern_slock_keys + sk->sk_family,
1423 af_family_kern_key_strings[sk->sk_family],
1424 af_family_kern_keys + sk->sk_family);
1425 else
1426 sock_lock_init_class_and_name(
1428 af_family_slock_key_strings[sk->sk_family],
1429 af_family_slock_keys + sk->sk_family,
1430 af_family_key_strings[sk->sk_family],
1431 af_family_keys + sk->sk_family);
1435 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1436 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1437 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1439 static void sock_copy(struct sock *nsk, const struct sock *osk)
1441 #ifdef CONFIG_SECURITY_NETWORK
1442 void *sptr = nsk->sk_security;
1443 #endif
1444 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1446 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1447 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1449 #ifdef CONFIG_SECURITY_NETWORK
1450 nsk->sk_security = sptr;
1451 security_sk_clone(osk, nsk);
1452 #endif
1455 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1456 int family)
1458 struct sock *sk;
1459 struct kmem_cache *slab;
1461 slab = prot->slab;
1462 if (slab != NULL) {
1463 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1464 if (!sk)
1465 return sk;
1466 if (priority & __GFP_ZERO)
1467 sk_prot_clear_nulls(sk, prot->obj_size);
1468 } else
1469 sk = kmalloc(prot->obj_size, priority);
1471 if (sk != NULL) {
1472 if (security_sk_alloc(sk, family, priority))
1473 goto out_free;
1475 if (!try_module_get(prot->owner))
1476 goto out_free_sec;
1477 sk_tx_queue_clear(sk);
1480 return sk;
1482 out_free_sec:
1483 security_sk_free(sk);
1484 out_free:
1485 if (slab != NULL)
1486 kmem_cache_free(slab, sk);
1487 else
1488 kfree(sk);
1489 return NULL;
1492 static void sk_prot_free(struct proto *prot, struct sock *sk)
1494 struct kmem_cache *slab;
1495 struct module *owner;
1497 owner = prot->owner;
1498 slab = prot->slab;
1500 cgroup_sk_free(&sk->sk_cgrp_data);
1501 mem_cgroup_sk_free(sk);
1502 security_sk_free(sk);
1503 if (slab != NULL)
1504 kmem_cache_free(slab, sk);
1505 else
1506 kfree(sk);
1507 module_put(owner);
1511 * sk_alloc - All socket objects are allocated here
1512 * @net: the applicable net namespace
1513 * @family: protocol family
1514 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1515 * @prot: struct proto associated with this new sock instance
1516 * @kern: is this to be a kernel socket?
1518 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1519 struct proto *prot, int kern)
1521 struct sock *sk;
1523 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1524 if (sk) {
1525 sk->sk_family = family;
1527 * See comment in struct sock definition to understand
1528 * why we need sk_prot_creator -acme
1530 sk->sk_prot = sk->sk_prot_creator = prot;
1531 sk->sk_kern_sock = kern;
1532 sock_lock_init(sk);
1533 sk->sk_net_refcnt = kern ? 0 : 1;
1534 if (likely(sk->sk_net_refcnt))
1535 get_net(net);
1536 sock_net_set(sk, net);
1537 refcount_set(&sk->sk_wmem_alloc, 1);
1539 mem_cgroup_sk_alloc(sk);
1540 cgroup_sk_alloc(&sk->sk_cgrp_data);
1541 sock_update_classid(&sk->sk_cgrp_data);
1542 sock_update_netprioidx(&sk->sk_cgrp_data);
1545 return sk;
1547 EXPORT_SYMBOL(sk_alloc);
1549 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1550 * grace period. This is the case for UDP sockets and TCP listeners.
1552 static void __sk_destruct(struct rcu_head *head)
1554 struct sock *sk = container_of(head, struct sock, sk_rcu);
1555 struct sk_filter *filter;
1557 if (sk->sk_destruct)
1558 sk->sk_destruct(sk);
1560 filter = rcu_dereference_check(sk->sk_filter,
1561 refcount_read(&sk->sk_wmem_alloc) == 0);
1562 if (filter) {
1563 sk_filter_uncharge(sk, filter);
1564 RCU_INIT_POINTER(sk->sk_filter, NULL);
1566 if (rcu_access_pointer(sk->sk_reuseport_cb))
1567 reuseport_detach_sock(sk);
1569 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1571 if (atomic_read(&sk->sk_omem_alloc))
1572 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1573 __func__, atomic_read(&sk->sk_omem_alloc));
1575 if (sk->sk_frag.page) {
1576 put_page(sk->sk_frag.page);
1577 sk->sk_frag.page = NULL;
1580 if (sk->sk_peer_cred)
1581 put_cred(sk->sk_peer_cred);
1582 put_pid(sk->sk_peer_pid);
1583 if (likely(sk->sk_net_refcnt))
1584 put_net(sock_net(sk));
1585 sk_prot_free(sk->sk_prot_creator, sk);
1588 void sk_destruct(struct sock *sk)
1590 if (sock_flag(sk, SOCK_RCU_FREE))
1591 call_rcu(&sk->sk_rcu, __sk_destruct);
1592 else
1593 __sk_destruct(&sk->sk_rcu);
1596 static void __sk_free(struct sock *sk)
1598 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1599 sock_diag_broadcast_destroy(sk);
1600 else
1601 sk_destruct(sk);
1604 void sk_free(struct sock *sk)
1607 * We subtract one from sk_wmem_alloc and can know if
1608 * some packets are still in some tx queue.
1609 * If not null, sock_wfree() will call __sk_free(sk) later
1611 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1612 __sk_free(sk);
1614 EXPORT_SYMBOL(sk_free);
1616 static void sk_init_common(struct sock *sk)
1618 skb_queue_head_init(&sk->sk_receive_queue);
1619 skb_queue_head_init(&sk->sk_write_queue);
1620 skb_queue_head_init(&sk->sk_error_queue);
1622 rwlock_init(&sk->sk_callback_lock);
1623 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1624 af_rlock_keys + sk->sk_family,
1625 af_family_rlock_key_strings[sk->sk_family]);
1626 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1627 af_wlock_keys + sk->sk_family,
1628 af_family_wlock_key_strings[sk->sk_family]);
1629 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1630 af_elock_keys + sk->sk_family,
1631 af_family_elock_key_strings[sk->sk_family]);
1632 lockdep_set_class_and_name(&sk->sk_callback_lock,
1633 af_callback_keys + sk->sk_family,
1634 af_family_clock_key_strings[sk->sk_family]);
1638 * sk_clone_lock - clone a socket, and lock its clone
1639 * @sk: the socket to clone
1640 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1642 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1644 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1646 struct sock *newsk;
1647 bool is_charged = true;
1649 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1650 if (newsk != NULL) {
1651 struct sk_filter *filter;
1653 sock_copy(newsk, sk);
1655 newsk->sk_prot_creator = sk->sk_prot;
1657 /* SANITY */
1658 if (likely(newsk->sk_net_refcnt))
1659 get_net(sock_net(newsk));
1660 sk_node_init(&newsk->sk_node);
1661 sock_lock_init(newsk);
1662 bh_lock_sock(newsk);
1663 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1664 newsk->sk_backlog.len = 0;
1666 atomic_set(&newsk->sk_rmem_alloc, 0);
1668 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1670 refcount_set(&newsk->sk_wmem_alloc, 1);
1671 atomic_set(&newsk->sk_omem_alloc, 0);
1672 sk_init_common(newsk);
1674 newsk->sk_dst_cache = NULL;
1675 newsk->sk_dst_pending_confirm = 0;
1676 newsk->sk_wmem_queued = 0;
1677 newsk->sk_forward_alloc = 0;
1679 /* sk->sk_memcg will be populated at accept() time */
1680 newsk->sk_memcg = NULL;
1682 atomic_set(&newsk->sk_drops, 0);
1683 newsk->sk_send_head = NULL;
1684 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1685 atomic_set(&newsk->sk_zckey, 0);
1687 sock_reset_flag(newsk, SOCK_DONE);
1688 cgroup_sk_alloc(&newsk->sk_cgrp_data);
1690 rcu_read_lock();
1691 filter = rcu_dereference(sk->sk_filter);
1692 if (filter != NULL)
1693 /* though it's an empty new sock, the charging may fail
1694 * if sysctl_optmem_max was changed between creation of
1695 * original socket and cloning
1697 is_charged = sk_filter_charge(newsk, filter);
1698 RCU_INIT_POINTER(newsk->sk_filter, filter);
1699 rcu_read_unlock();
1701 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1702 /* We need to make sure that we don't uncharge the new
1703 * socket if we couldn't charge it in the first place
1704 * as otherwise we uncharge the parent's filter.
1706 if (!is_charged)
1707 RCU_INIT_POINTER(newsk->sk_filter, NULL);
1708 sk_free_unlock_clone(newsk);
1709 newsk = NULL;
1710 goto out;
1712 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1714 newsk->sk_err = 0;
1715 newsk->sk_err_soft = 0;
1716 newsk->sk_priority = 0;
1717 newsk->sk_incoming_cpu = raw_smp_processor_id();
1718 atomic64_set(&newsk->sk_cookie, 0);
1721 * Before updating sk_refcnt, we must commit prior changes to memory
1722 * (Documentation/RCU/rculist_nulls.txt for details)
1724 smp_wmb();
1725 refcount_set(&newsk->sk_refcnt, 2);
1728 * Increment the counter in the same struct proto as the master
1729 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1730 * is the same as sk->sk_prot->socks, as this field was copied
1731 * with memcpy).
1733 * This _changes_ the previous behaviour, where
1734 * tcp_create_openreq_child always was incrementing the
1735 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1736 * to be taken into account in all callers. -acme
1738 sk_refcnt_debug_inc(newsk);
1739 sk_set_socket(newsk, NULL);
1740 newsk->sk_wq = NULL;
1742 if (newsk->sk_prot->sockets_allocated)
1743 sk_sockets_allocated_inc(newsk);
1745 if (sock_needs_netstamp(sk) &&
1746 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1747 net_enable_timestamp();
1749 out:
1750 return newsk;
1752 EXPORT_SYMBOL_GPL(sk_clone_lock);
1754 void sk_free_unlock_clone(struct sock *sk)
1756 /* It is still raw copy of parent, so invalidate
1757 * destructor and make plain sk_free() */
1758 sk->sk_destruct = NULL;
1759 bh_unlock_sock(sk);
1760 sk_free(sk);
1762 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1764 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1766 u32 max_segs = 1;
1768 sk_dst_set(sk, dst);
1769 sk->sk_route_caps = dst->dev->features;
1770 if (sk->sk_route_caps & NETIF_F_GSO)
1771 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1772 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1773 if (sk_can_gso(sk)) {
1774 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1775 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1776 } else {
1777 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1778 sk->sk_gso_max_size = dst->dev->gso_max_size;
1779 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1782 sk->sk_gso_max_segs = max_segs;
1784 EXPORT_SYMBOL_GPL(sk_setup_caps);
1787 * Simple resource managers for sockets.
1792 * Write buffer destructor automatically called from kfree_skb.
1794 void sock_wfree(struct sk_buff *skb)
1796 struct sock *sk = skb->sk;
1797 unsigned int len = skb->truesize;
1799 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1801 * Keep a reference on sk_wmem_alloc, this will be released
1802 * after sk_write_space() call
1804 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1805 sk->sk_write_space(sk);
1806 len = 1;
1809 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1810 * could not do because of in-flight packets
1812 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1813 __sk_free(sk);
1815 EXPORT_SYMBOL(sock_wfree);
1817 /* This variant of sock_wfree() is used by TCP,
1818 * since it sets SOCK_USE_WRITE_QUEUE.
1820 void __sock_wfree(struct sk_buff *skb)
1822 struct sock *sk = skb->sk;
1824 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1825 __sk_free(sk);
1828 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1830 skb_orphan(skb);
1831 skb->sk = sk;
1832 #ifdef CONFIG_INET
1833 if (unlikely(!sk_fullsock(sk))) {
1834 skb->destructor = sock_edemux;
1835 sock_hold(sk);
1836 return;
1838 #endif
1839 skb->destructor = sock_wfree;
1840 skb_set_hash_from_sk(skb, sk);
1842 * We used to take a refcount on sk, but following operation
1843 * is enough to guarantee sk_free() wont free this sock until
1844 * all in-flight packets are completed
1846 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1848 EXPORT_SYMBOL(skb_set_owner_w);
1850 /* This helper is used by netem, as it can hold packets in its
1851 * delay queue. We want to allow the owner socket to send more
1852 * packets, as if they were already TX completed by a typical driver.
1853 * But we also want to keep skb->sk set because some packet schedulers
1854 * rely on it (sch_fq for example).
1856 void skb_orphan_partial(struct sk_buff *skb)
1858 if (skb_is_tcp_pure_ack(skb))
1859 return;
1861 if (skb->destructor == sock_wfree
1862 #ifdef CONFIG_INET
1863 || skb->destructor == tcp_wfree
1864 #endif
1866 struct sock *sk = skb->sk;
1868 if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1869 WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
1870 skb->destructor = sock_efree;
1872 } else {
1873 skb_orphan(skb);
1876 EXPORT_SYMBOL(skb_orphan_partial);
1879 * Read buffer destructor automatically called from kfree_skb.
1881 void sock_rfree(struct sk_buff *skb)
1883 struct sock *sk = skb->sk;
1884 unsigned int len = skb->truesize;
1886 atomic_sub(len, &sk->sk_rmem_alloc);
1887 sk_mem_uncharge(sk, len);
1889 EXPORT_SYMBOL(sock_rfree);
1892 * Buffer destructor for skbs that are not used directly in read or write
1893 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1895 void sock_efree(struct sk_buff *skb)
1897 sock_put(skb->sk);
1899 EXPORT_SYMBOL(sock_efree);
1901 kuid_t sock_i_uid(struct sock *sk)
1903 kuid_t uid;
1905 read_lock_bh(&sk->sk_callback_lock);
1906 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1907 read_unlock_bh(&sk->sk_callback_lock);
1908 return uid;
1910 EXPORT_SYMBOL(sock_i_uid);
1912 unsigned long sock_i_ino(struct sock *sk)
1914 unsigned long ino;
1916 read_lock_bh(&sk->sk_callback_lock);
1917 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1918 read_unlock_bh(&sk->sk_callback_lock);
1919 return ino;
1921 EXPORT_SYMBOL(sock_i_ino);
1924 * Allocate a skb from the socket's send buffer.
1926 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1927 gfp_t priority)
1929 if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1930 struct sk_buff *skb = alloc_skb(size, priority);
1931 if (skb) {
1932 skb_set_owner_w(skb, sk);
1933 return skb;
1936 return NULL;
1938 EXPORT_SYMBOL(sock_wmalloc);
1940 static void sock_ofree(struct sk_buff *skb)
1942 struct sock *sk = skb->sk;
1944 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
1947 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1948 gfp_t priority)
1950 struct sk_buff *skb;
1952 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
1953 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
1954 sysctl_optmem_max)
1955 return NULL;
1957 skb = alloc_skb(size, priority);
1958 if (!skb)
1959 return NULL;
1961 atomic_add(skb->truesize, &sk->sk_omem_alloc);
1962 skb->sk = sk;
1963 skb->destructor = sock_ofree;
1964 return skb;
1968 * Allocate a memory block from the socket's option memory buffer.
1970 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1972 if ((unsigned int)size <= sysctl_optmem_max &&
1973 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1974 void *mem;
1975 /* First do the add, to avoid the race if kmalloc
1976 * might sleep.
1978 atomic_add(size, &sk->sk_omem_alloc);
1979 mem = kmalloc(size, priority);
1980 if (mem)
1981 return mem;
1982 atomic_sub(size, &sk->sk_omem_alloc);
1984 return NULL;
1986 EXPORT_SYMBOL(sock_kmalloc);
1988 /* Free an option memory block. Note, we actually want the inline
1989 * here as this allows gcc to detect the nullify and fold away the
1990 * condition entirely.
1992 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1993 const bool nullify)
1995 if (WARN_ON_ONCE(!mem))
1996 return;
1997 if (nullify)
1998 kzfree(mem);
1999 else
2000 kfree(mem);
2001 atomic_sub(size, &sk->sk_omem_alloc);
2004 void sock_kfree_s(struct sock *sk, void *mem, int size)
2006 __sock_kfree_s(sk, mem, size, false);
2008 EXPORT_SYMBOL(sock_kfree_s);
2010 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2012 __sock_kfree_s(sk, mem, size, true);
2014 EXPORT_SYMBOL(sock_kzfree_s);
2016 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2017 I think, these locks should be removed for datagram sockets.
2019 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2021 DEFINE_WAIT(wait);
2023 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2024 for (;;) {
2025 if (!timeo)
2026 break;
2027 if (signal_pending(current))
2028 break;
2029 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2030 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2031 if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2032 break;
2033 if (sk->sk_shutdown & SEND_SHUTDOWN)
2034 break;
2035 if (sk->sk_err)
2036 break;
2037 timeo = schedule_timeout(timeo);
2039 finish_wait(sk_sleep(sk), &wait);
2040 return timeo;
2045 * Generic send/receive buffer handlers
2048 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2049 unsigned long data_len, int noblock,
2050 int *errcode, int max_page_order)
2052 struct sk_buff *skb;
2053 long timeo;
2054 int err;
2056 timeo = sock_sndtimeo(sk, noblock);
2057 for (;;) {
2058 err = sock_error(sk);
2059 if (err != 0)
2060 goto failure;
2062 err = -EPIPE;
2063 if (sk->sk_shutdown & SEND_SHUTDOWN)
2064 goto failure;
2066 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2067 break;
2069 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2070 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2071 err = -EAGAIN;
2072 if (!timeo)
2073 goto failure;
2074 if (signal_pending(current))
2075 goto interrupted;
2076 timeo = sock_wait_for_wmem(sk, timeo);
2078 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2079 errcode, sk->sk_allocation);
2080 if (skb)
2081 skb_set_owner_w(skb, sk);
2082 return skb;
2084 interrupted:
2085 err = sock_intr_errno(timeo);
2086 failure:
2087 *errcode = err;
2088 return NULL;
2090 EXPORT_SYMBOL(sock_alloc_send_pskb);
2092 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2093 int noblock, int *errcode)
2095 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2097 EXPORT_SYMBOL(sock_alloc_send_skb);
2099 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2100 struct sockcm_cookie *sockc)
2102 u32 tsflags;
2104 switch (cmsg->cmsg_type) {
2105 case SO_MARK:
2106 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2107 return -EPERM;
2108 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2109 return -EINVAL;
2110 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2111 break;
2112 case SO_TIMESTAMPING:
2113 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2114 return -EINVAL;
2116 tsflags = *(u32 *)CMSG_DATA(cmsg);
2117 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2118 return -EINVAL;
2120 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2121 sockc->tsflags |= tsflags;
2122 break;
2123 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2124 case SCM_RIGHTS:
2125 case SCM_CREDENTIALS:
2126 break;
2127 default:
2128 return -EINVAL;
2130 return 0;
2132 EXPORT_SYMBOL(__sock_cmsg_send);
2134 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2135 struct sockcm_cookie *sockc)
2137 struct cmsghdr *cmsg;
2138 int ret;
2140 for_each_cmsghdr(cmsg, msg) {
2141 if (!CMSG_OK(msg, cmsg))
2142 return -EINVAL;
2143 if (cmsg->cmsg_level != SOL_SOCKET)
2144 continue;
2145 ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2146 if (ret)
2147 return ret;
2149 return 0;
2151 EXPORT_SYMBOL(sock_cmsg_send);
2153 static void sk_enter_memory_pressure(struct sock *sk)
2155 if (!sk->sk_prot->enter_memory_pressure)
2156 return;
2158 sk->sk_prot->enter_memory_pressure(sk);
2161 static void sk_leave_memory_pressure(struct sock *sk)
2163 if (sk->sk_prot->leave_memory_pressure) {
2164 sk->sk_prot->leave_memory_pressure(sk);
2165 } else {
2166 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2168 if (memory_pressure && *memory_pressure)
2169 *memory_pressure = 0;
2173 /* On 32bit arches, an skb frag is limited to 2^15 */
2174 #define SKB_FRAG_PAGE_ORDER get_order(32768)
2177 * skb_page_frag_refill - check that a page_frag contains enough room
2178 * @sz: minimum size of the fragment we want to get
2179 * @pfrag: pointer to page_frag
2180 * @gfp: priority for memory allocation
2182 * Note: While this allocator tries to use high order pages, there is
2183 * no guarantee that allocations succeed. Therefore, @sz MUST be
2184 * less or equal than PAGE_SIZE.
2186 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2188 if (pfrag->page) {
2189 if (page_ref_count(pfrag->page) == 1) {
2190 pfrag->offset = 0;
2191 return true;
2193 if (pfrag->offset + sz <= pfrag->size)
2194 return true;
2195 put_page(pfrag->page);
2198 pfrag->offset = 0;
2199 if (SKB_FRAG_PAGE_ORDER) {
2200 /* Avoid direct reclaim but allow kswapd to wake */
2201 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2202 __GFP_COMP | __GFP_NOWARN |
2203 __GFP_NORETRY,
2204 SKB_FRAG_PAGE_ORDER);
2205 if (likely(pfrag->page)) {
2206 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2207 return true;
2210 pfrag->page = alloc_page(gfp);
2211 if (likely(pfrag->page)) {
2212 pfrag->size = PAGE_SIZE;
2213 return true;
2215 return false;
2217 EXPORT_SYMBOL(skb_page_frag_refill);
2219 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2221 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2222 return true;
2224 sk_enter_memory_pressure(sk);
2225 sk_stream_moderate_sndbuf(sk);
2226 return false;
2228 EXPORT_SYMBOL(sk_page_frag_refill);
2230 static void __lock_sock(struct sock *sk)
2231 __releases(&sk->sk_lock.slock)
2232 __acquires(&sk->sk_lock.slock)
2234 DEFINE_WAIT(wait);
2236 for (;;) {
2237 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2238 TASK_UNINTERRUPTIBLE);
2239 spin_unlock_bh(&sk->sk_lock.slock);
2240 schedule();
2241 spin_lock_bh(&sk->sk_lock.slock);
2242 if (!sock_owned_by_user(sk))
2243 break;
2245 finish_wait(&sk->sk_lock.wq, &wait);
2248 static void __release_sock(struct sock *sk)
2249 __releases(&sk->sk_lock.slock)
2250 __acquires(&sk->sk_lock.slock)
2252 struct sk_buff *skb, *next;
2254 while ((skb = sk->sk_backlog.head) != NULL) {
2255 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2257 spin_unlock_bh(&sk->sk_lock.slock);
2259 do {
2260 next = skb->next;
2261 prefetch(next);
2262 WARN_ON_ONCE(skb_dst_is_noref(skb));
2263 skb->next = NULL;
2264 sk_backlog_rcv(sk, skb);
2266 cond_resched();
2268 skb = next;
2269 } while (skb != NULL);
2271 spin_lock_bh(&sk->sk_lock.slock);
2275 * Doing the zeroing here guarantee we can not loop forever
2276 * while a wild producer attempts to flood us.
2278 sk->sk_backlog.len = 0;
2281 void __sk_flush_backlog(struct sock *sk)
2283 spin_lock_bh(&sk->sk_lock.slock);
2284 __release_sock(sk);
2285 spin_unlock_bh(&sk->sk_lock.slock);
2289 * sk_wait_data - wait for data to arrive at sk_receive_queue
2290 * @sk: sock to wait on
2291 * @timeo: for how long
2292 * @skb: last skb seen on sk_receive_queue
2294 * Now socket state including sk->sk_err is changed only under lock,
2295 * hence we may omit checks after joining wait queue.
2296 * We check receive queue before schedule() only as optimization;
2297 * it is very likely that release_sock() added new data.
2299 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2301 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2302 int rc;
2304 add_wait_queue(sk_sleep(sk), &wait);
2305 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2306 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2307 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2308 remove_wait_queue(sk_sleep(sk), &wait);
2309 return rc;
2311 EXPORT_SYMBOL(sk_wait_data);
2314 * __sk_mem_raise_allocated - increase memory_allocated
2315 * @sk: socket
2316 * @size: memory size to allocate
2317 * @amt: pages to allocate
2318 * @kind: allocation type
2320 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2322 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2324 struct proto *prot = sk->sk_prot;
2325 long allocated = sk_memory_allocated_add(sk, amt);
2327 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2328 !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2329 goto suppress_allocation;
2331 /* Under limit. */
2332 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2333 sk_leave_memory_pressure(sk);
2334 return 1;
2337 /* Under pressure. */
2338 if (allocated > sk_prot_mem_limits(sk, 1))
2339 sk_enter_memory_pressure(sk);
2341 /* Over hard limit. */
2342 if (allocated > sk_prot_mem_limits(sk, 2))
2343 goto suppress_allocation;
2345 /* guarantee minimum buffer size under pressure */
2346 if (kind == SK_MEM_RECV) {
2347 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2348 return 1;
2350 } else { /* SK_MEM_SEND */
2351 int wmem0 = sk_get_wmem0(sk, prot);
2353 if (sk->sk_type == SOCK_STREAM) {
2354 if (sk->sk_wmem_queued < wmem0)
2355 return 1;
2356 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2357 return 1;
2361 if (sk_has_memory_pressure(sk)) {
2362 int alloc;
2364 if (!sk_under_memory_pressure(sk))
2365 return 1;
2366 alloc = sk_sockets_allocated_read_positive(sk);
2367 if (sk_prot_mem_limits(sk, 2) > alloc *
2368 sk_mem_pages(sk->sk_wmem_queued +
2369 atomic_read(&sk->sk_rmem_alloc) +
2370 sk->sk_forward_alloc))
2371 return 1;
2374 suppress_allocation:
2376 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2377 sk_stream_moderate_sndbuf(sk);
2379 /* Fail only if socket is _under_ its sndbuf.
2380 * In this case we cannot block, so that we have to fail.
2382 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2383 return 1;
2386 trace_sock_exceed_buf_limit(sk, prot, allocated);
2388 sk_memory_allocated_sub(sk, amt);
2390 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2391 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2393 return 0;
2395 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2398 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2399 * @sk: socket
2400 * @size: memory size to allocate
2401 * @kind: allocation type
2403 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2404 * rmem allocation. This function assumes that protocols which have
2405 * memory_pressure use sk_wmem_queued as write buffer accounting.
2407 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2409 int ret, amt = sk_mem_pages(size);
2411 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2412 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2413 if (!ret)
2414 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2415 return ret;
2417 EXPORT_SYMBOL(__sk_mem_schedule);
2420 * __sk_mem_reduce_allocated - reclaim memory_allocated
2421 * @sk: socket
2422 * @amount: number of quanta
2424 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2426 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2428 sk_memory_allocated_sub(sk, amount);
2430 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2431 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2433 if (sk_under_memory_pressure(sk) &&
2434 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2435 sk_leave_memory_pressure(sk);
2437 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2440 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2441 * @sk: socket
2442 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2444 void __sk_mem_reclaim(struct sock *sk, int amount)
2446 amount >>= SK_MEM_QUANTUM_SHIFT;
2447 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2448 __sk_mem_reduce_allocated(sk, amount);
2450 EXPORT_SYMBOL(__sk_mem_reclaim);
2452 int sk_set_peek_off(struct sock *sk, int val)
2454 sk->sk_peek_off = val;
2455 return 0;
2457 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2460 * Set of default routines for initialising struct proto_ops when
2461 * the protocol does not support a particular function. In certain
2462 * cases where it makes no sense for a protocol to have a "do nothing"
2463 * function, some default processing is provided.
2466 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2468 return -EOPNOTSUPP;
2470 EXPORT_SYMBOL(sock_no_bind);
2472 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2473 int len, int flags)
2475 return -EOPNOTSUPP;
2477 EXPORT_SYMBOL(sock_no_connect);
2479 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2481 return -EOPNOTSUPP;
2483 EXPORT_SYMBOL(sock_no_socketpair);
2485 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2486 bool kern)
2488 return -EOPNOTSUPP;
2490 EXPORT_SYMBOL(sock_no_accept);
2492 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2493 int *len, int peer)
2495 return -EOPNOTSUPP;
2497 EXPORT_SYMBOL(sock_no_getname);
2499 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2501 return 0;
2503 EXPORT_SYMBOL(sock_no_poll);
2505 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2507 return -EOPNOTSUPP;
2509 EXPORT_SYMBOL(sock_no_ioctl);
2511 int sock_no_listen(struct socket *sock, int backlog)
2513 return -EOPNOTSUPP;
2515 EXPORT_SYMBOL(sock_no_listen);
2517 int sock_no_shutdown(struct socket *sock, int how)
2519 return -EOPNOTSUPP;
2521 EXPORT_SYMBOL(sock_no_shutdown);
2523 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2524 char __user *optval, unsigned int optlen)
2526 return -EOPNOTSUPP;
2528 EXPORT_SYMBOL(sock_no_setsockopt);
2530 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2531 char __user *optval, int __user *optlen)
2533 return -EOPNOTSUPP;
2535 EXPORT_SYMBOL(sock_no_getsockopt);
2537 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2539 return -EOPNOTSUPP;
2541 EXPORT_SYMBOL(sock_no_sendmsg);
2543 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2545 return -EOPNOTSUPP;
2547 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2549 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2550 int flags)
2552 return -EOPNOTSUPP;
2554 EXPORT_SYMBOL(sock_no_recvmsg);
2556 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2558 /* Mirror missing mmap method error code */
2559 return -ENODEV;
2561 EXPORT_SYMBOL(sock_no_mmap);
2563 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2565 ssize_t res;
2566 struct msghdr msg = {.msg_flags = flags};
2567 struct kvec iov;
2568 char *kaddr = kmap(page);
2569 iov.iov_base = kaddr + offset;
2570 iov.iov_len = size;
2571 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2572 kunmap(page);
2573 return res;
2575 EXPORT_SYMBOL(sock_no_sendpage);
2577 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2578 int offset, size_t size, int flags)
2580 ssize_t res;
2581 struct msghdr msg = {.msg_flags = flags};
2582 struct kvec iov;
2583 char *kaddr = kmap(page);
2585 iov.iov_base = kaddr + offset;
2586 iov.iov_len = size;
2587 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2588 kunmap(page);
2589 return res;
2591 EXPORT_SYMBOL(sock_no_sendpage_locked);
2594 * Default Socket Callbacks
2597 static void sock_def_wakeup(struct sock *sk)
2599 struct socket_wq *wq;
2601 rcu_read_lock();
2602 wq = rcu_dereference(sk->sk_wq);
2603 if (skwq_has_sleeper(wq))
2604 wake_up_interruptible_all(&wq->wait);
2605 rcu_read_unlock();
2608 static void sock_def_error_report(struct sock *sk)
2610 struct socket_wq *wq;
2612 rcu_read_lock();
2613 wq = rcu_dereference(sk->sk_wq);
2614 if (skwq_has_sleeper(wq))
2615 wake_up_interruptible_poll(&wq->wait, POLLERR);
2616 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2617 rcu_read_unlock();
2620 static void sock_def_readable(struct sock *sk)
2622 struct socket_wq *wq;
2624 rcu_read_lock();
2625 wq = rcu_dereference(sk->sk_wq);
2626 if (skwq_has_sleeper(wq))
2627 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2628 POLLRDNORM | POLLRDBAND);
2629 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2630 rcu_read_unlock();
2633 static void sock_def_write_space(struct sock *sk)
2635 struct socket_wq *wq;
2637 rcu_read_lock();
2639 /* Do not wake up a writer until he can make "significant"
2640 * progress. --DaveM
2642 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2643 wq = rcu_dereference(sk->sk_wq);
2644 if (skwq_has_sleeper(wq))
2645 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2646 POLLWRNORM | POLLWRBAND);
2648 /* Should agree with poll, otherwise some programs break */
2649 if (sock_writeable(sk))
2650 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2653 rcu_read_unlock();
2656 static void sock_def_destruct(struct sock *sk)
2660 void sk_send_sigurg(struct sock *sk)
2662 if (sk->sk_socket && sk->sk_socket->file)
2663 if (send_sigurg(&sk->sk_socket->file->f_owner))
2664 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2666 EXPORT_SYMBOL(sk_send_sigurg);
2668 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2669 unsigned long expires)
2671 if (!mod_timer(timer, expires))
2672 sock_hold(sk);
2674 EXPORT_SYMBOL(sk_reset_timer);
2676 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2678 if (del_timer(timer))
2679 __sock_put(sk);
2681 EXPORT_SYMBOL(sk_stop_timer);
2683 void sock_init_data(struct socket *sock, struct sock *sk)
2685 sk_init_common(sk);
2686 sk->sk_send_head = NULL;
2688 timer_setup(&sk->sk_timer, NULL, 0);
2690 sk->sk_allocation = GFP_KERNEL;
2691 sk->sk_rcvbuf = sysctl_rmem_default;
2692 sk->sk_sndbuf = sysctl_wmem_default;
2693 sk->sk_state = TCP_CLOSE;
2694 sk_set_socket(sk, sock);
2696 sock_set_flag(sk, SOCK_ZAPPED);
2698 if (sock) {
2699 sk->sk_type = sock->type;
2700 sk->sk_wq = sock->wq;
2701 sock->sk = sk;
2702 sk->sk_uid = SOCK_INODE(sock)->i_uid;
2703 } else {
2704 sk->sk_wq = NULL;
2705 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0);
2708 rwlock_init(&sk->sk_callback_lock);
2709 if (sk->sk_kern_sock)
2710 lockdep_set_class_and_name(
2711 &sk->sk_callback_lock,
2712 af_kern_callback_keys + sk->sk_family,
2713 af_family_kern_clock_key_strings[sk->sk_family]);
2714 else
2715 lockdep_set_class_and_name(
2716 &sk->sk_callback_lock,
2717 af_callback_keys + sk->sk_family,
2718 af_family_clock_key_strings[sk->sk_family]);
2720 sk->sk_state_change = sock_def_wakeup;
2721 sk->sk_data_ready = sock_def_readable;
2722 sk->sk_write_space = sock_def_write_space;
2723 sk->sk_error_report = sock_def_error_report;
2724 sk->sk_destruct = sock_def_destruct;
2726 sk->sk_frag.page = NULL;
2727 sk->sk_frag.offset = 0;
2728 sk->sk_peek_off = -1;
2730 sk->sk_peer_pid = NULL;
2731 sk->sk_peer_cred = NULL;
2732 sk->sk_write_pending = 0;
2733 sk->sk_rcvlowat = 1;
2734 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2735 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2737 sk->sk_stamp = SK_DEFAULT_STAMP;
2738 atomic_set(&sk->sk_zckey, 0);
2740 #ifdef CONFIG_NET_RX_BUSY_POLL
2741 sk->sk_napi_id = 0;
2742 sk->sk_ll_usec = sysctl_net_busy_read;
2743 #endif
2745 sk->sk_max_pacing_rate = ~0U;
2746 sk->sk_pacing_rate = ~0U;
2747 sk->sk_pacing_shift = 10;
2748 sk->sk_incoming_cpu = -1;
2750 * Before updating sk_refcnt, we must commit prior changes to memory
2751 * (Documentation/RCU/rculist_nulls.txt for details)
2753 smp_wmb();
2754 refcount_set(&sk->sk_refcnt, 1);
2755 atomic_set(&sk->sk_drops, 0);
2757 EXPORT_SYMBOL(sock_init_data);
2759 void lock_sock_nested(struct sock *sk, int subclass)
2761 might_sleep();
2762 spin_lock_bh(&sk->sk_lock.slock);
2763 if (sk->sk_lock.owned)
2764 __lock_sock(sk);
2765 sk->sk_lock.owned = 1;
2766 spin_unlock(&sk->sk_lock.slock);
2768 * The sk_lock has mutex_lock() semantics here:
2770 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2771 local_bh_enable();
2773 EXPORT_SYMBOL(lock_sock_nested);
2775 void release_sock(struct sock *sk)
2777 spin_lock_bh(&sk->sk_lock.slock);
2778 if (sk->sk_backlog.tail)
2779 __release_sock(sk);
2781 /* Warning : release_cb() might need to release sk ownership,
2782 * ie call sock_release_ownership(sk) before us.
2784 if (sk->sk_prot->release_cb)
2785 sk->sk_prot->release_cb(sk);
2787 sock_release_ownership(sk);
2788 if (waitqueue_active(&sk->sk_lock.wq))
2789 wake_up(&sk->sk_lock.wq);
2790 spin_unlock_bh(&sk->sk_lock.slock);
2792 EXPORT_SYMBOL(release_sock);
2795 * lock_sock_fast - fast version of lock_sock
2796 * @sk: socket
2798 * This version should be used for very small section, where process wont block
2799 * return false if fast path is taken:
2801 * sk_lock.slock locked, owned = 0, BH disabled
2803 * return true if slow path is taken:
2805 * sk_lock.slock unlocked, owned = 1, BH enabled
2807 bool lock_sock_fast(struct sock *sk)
2809 might_sleep();
2810 spin_lock_bh(&sk->sk_lock.slock);
2812 if (!sk->sk_lock.owned)
2814 * Note : We must disable BH
2816 return false;
2818 __lock_sock(sk);
2819 sk->sk_lock.owned = 1;
2820 spin_unlock(&sk->sk_lock.slock);
2822 * The sk_lock has mutex_lock() semantics here:
2824 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2825 local_bh_enable();
2826 return true;
2828 EXPORT_SYMBOL(lock_sock_fast);
2830 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2832 struct timeval tv;
2833 if (!sock_flag(sk, SOCK_TIMESTAMP))
2834 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2835 tv = ktime_to_timeval(sk->sk_stamp);
2836 if (tv.tv_sec == -1)
2837 return -ENOENT;
2838 if (tv.tv_sec == 0) {
2839 sk->sk_stamp = ktime_get_real();
2840 tv = ktime_to_timeval(sk->sk_stamp);
2842 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2844 EXPORT_SYMBOL(sock_get_timestamp);
2846 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2848 struct timespec ts;
2849 if (!sock_flag(sk, SOCK_TIMESTAMP))
2850 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2851 ts = ktime_to_timespec(sk->sk_stamp);
2852 if (ts.tv_sec == -1)
2853 return -ENOENT;
2854 if (ts.tv_sec == 0) {
2855 sk->sk_stamp = ktime_get_real();
2856 ts = ktime_to_timespec(sk->sk_stamp);
2858 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2860 EXPORT_SYMBOL(sock_get_timestampns);
2862 void sock_enable_timestamp(struct sock *sk, int flag)
2864 if (!sock_flag(sk, flag)) {
2865 unsigned long previous_flags = sk->sk_flags;
2867 sock_set_flag(sk, flag);
2869 * we just set one of the two flags which require net
2870 * time stamping, but time stamping might have been on
2871 * already because of the other one
2873 if (sock_needs_netstamp(sk) &&
2874 !(previous_flags & SK_FLAGS_TIMESTAMP))
2875 net_enable_timestamp();
2879 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2880 int level, int type)
2882 struct sock_exterr_skb *serr;
2883 struct sk_buff *skb;
2884 int copied, err;
2886 err = -EAGAIN;
2887 skb = sock_dequeue_err_skb(sk);
2888 if (skb == NULL)
2889 goto out;
2891 copied = skb->len;
2892 if (copied > len) {
2893 msg->msg_flags |= MSG_TRUNC;
2894 copied = len;
2896 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2897 if (err)
2898 goto out_free_skb;
2900 sock_recv_timestamp(msg, sk, skb);
2902 serr = SKB_EXT_ERR(skb);
2903 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2905 msg->msg_flags |= MSG_ERRQUEUE;
2906 err = copied;
2908 out_free_skb:
2909 kfree_skb(skb);
2910 out:
2911 return err;
2913 EXPORT_SYMBOL(sock_recv_errqueue);
2916 * Get a socket option on an socket.
2918 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2919 * asynchronous errors should be reported by getsockopt. We assume
2920 * this means if you specify SO_ERROR (otherwise whats the point of it).
2922 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2923 char __user *optval, int __user *optlen)
2925 struct sock *sk = sock->sk;
2927 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2929 EXPORT_SYMBOL(sock_common_getsockopt);
2931 #ifdef CONFIG_COMPAT
2932 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2933 char __user *optval, int __user *optlen)
2935 struct sock *sk = sock->sk;
2937 if (sk->sk_prot->compat_getsockopt != NULL)
2938 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2939 optval, optlen);
2940 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2942 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2943 #endif
2945 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2946 int flags)
2948 struct sock *sk = sock->sk;
2949 int addr_len = 0;
2950 int err;
2952 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2953 flags & ~MSG_DONTWAIT, &addr_len);
2954 if (err >= 0)
2955 msg->msg_namelen = addr_len;
2956 return err;
2958 EXPORT_SYMBOL(sock_common_recvmsg);
2961 * Set socket options on an inet socket.
2963 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2964 char __user *optval, unsigned int optlen)
2966 struct sock *sk = sock->sk;
2968 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2970 EXPORT_SYMBOL(sock_common_setsockopt);
2972 #ifdef CONFIG_COMPAT
2973 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2974 char __user *optval, unsigned int optlen)
2976 struct sock *sk = sock->sk;
2978 if (sk->sk_prot->compat_setsockopt != NULL)
2979 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2980 optval, optlen);
2981 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2983 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2984 #endif
2986 void sk_common_release(struct sock *sk)
2988 if (sk->sk_prot->destroy)
2989 sk->sk_prot->destroy(sk);
2992 * Observation: when sock_common_release is called, processes have
2993 * no access to socket. But net still has.
2994 * Step one, detach it from networking:
2996 * A. Remove from hash tables.
2999 sk->sk_prot->unhash(sk);
3002 * In this point socket cannot receive new packets, but it is possible
3003 * that some packets are in flight because some CPU runs receiver and
3004 * did hash table lookup before we unhashed socket. They will achieve
3005 * receive queue and will be purged by socket destructor.
3007 * Also we still have packets pending on receive queue and probably,
3008 * our own packets waiting in device queues. sock_destroy will drain
3009 * receive queue, but transmitted packets will delay socket destruction
3010 * until the last reference will be released.
3013 sock_orphan(sk);
3015 xfrm_sk_free_policy(sk);
3017 sk_refcnt_debug_release(sk);
3019 sock_put(sk);
3021 EXPORT_SYMBOL(sk_common_release);
3023 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3025 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3027 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3028 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3029 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3030 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3031 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3032 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3033 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3034 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3035 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3038 #ifdef CONFIG_PROC_FS
3039 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
3040 struct prot_inuse {
3041 int val[PROTO_INUSE_NR];
3044 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3046 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3048 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
3050 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3052 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3054 int cpu, idx = prot->inuse_idx;
3055 int res = 0;
3057 for_each_possible_cpu(cpu)
3058 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
3060 return res >= 0 ? res : 0;
3062 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3064 static int __net_init sock_inuse_init_net(struct net *net)
3066 net->core.inuse = alloc_percpu(struct prot_inuse);
3067 return net->core.inuse ? 0 : -ENOMEM;
3070 static void __net_exit sock_inuse_exit_net(struct net *net)
3072 free_percpu(net->core.inuse);
3075 static struct pernet_operations net_inuse_ops = {
3076 .init = sock_inuse_init_net,
3077 .exit = sock_inuse_exit_net,
3080 static __init int net_inuse_init(void)
3082 if (register_pernet_subsys(&net_inuse_ops))
3083 panic("Cannot initialize net inuse counters");
3085 return 0;
3088 core_initcall(net_inuse_init);
3090 static void assign_proto_idx(struct proto *prot)
3092 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3094 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3095 pr_err("PROTO_INUSE_NR exhausted\n");
3096 return;
3099 set_bit(prot->inuse_idx, proto_inuse_idx);
3102 static void release_proto_idx(struct proto *prot)
3104 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3105 clear_bit(prot->inuse_idx, proto_inuse_idx);
3107 #else
3108 static inline void assign_proto_idx(struct proto *prot)
3112 static inline void release_proto_idx(struct proto *prot)
3115 #endif
3117 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3119 if (!rsk_prot)
3120 return;
3121 kfree(rsk_prot->slab_name);
3122 rsk_prot->slab_name = NULL;
3123 kmem_cache_destroy(rsk_prot->slab);
3124 rsk_prot->slab = NULL;
3127 static int req_prot_init(const struct proto *prot)
3129 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3131 if (!rsk_prot)
3132 return 0;
3134 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3135 prot->name);
3136 if (!rsk_prot->slab_name)
3137 return -ENOMEM;
3139 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3140 rsk_prot->obj_size, 0,
3141 prot->slab_flags, NULL);
3143 if (!rsk_prot->slab) {
3144 pr_crit("%s: Can't create request sock SLAB cache!\n",
3145 prot->name);
3146 return -ENOMEM;
3148 return 0;
3151 int proto_register(struct proto *prot, int alloc_slab)
3153 if (alloc_slab) {
3154 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
3155 SLAB_HWCACHE_ALIGN | prot->slab_flags,
3156 NULL);
3158 if (prot->slab == NULL) {
3159 pr_crit("%s: Can't create sock SLAB cache!\n",
3160 prot->name);
3161 goto out;
3164 if (req_prot_init(prot))
3165 goto out_free_request_sock_slab;
3167 if (prot->twsk_prot != NULL) {
3168 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3170 if (prot->twsk_prot->twsk_slab_name == NULL)
3171 goto out_free_request_sock_slab;
3173 prot->twsk_prot->twsk_slab =
3174 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3175 prot->twsk_prot->twsk_obj_size,
3177 prot->slab_flags,
3178 NULL);
3179 if (prot->twsk_prot->twsk_slab == NULL)
3180 goto out_free_timewait_sock_slab_name;
3184 mutex_lock(&proto_list_mutex);
3185 list_add(&prot->node, &proto_list);
3186 assign_proto_idx(prot);
3187 mutex_unlock(&proto_list_mutex);
3188 return 0;
3190 out_free_timewait_sock_slab_name:
3191 kfree(prot->twsk_prot->twsk_slab_name);
3192 out_free_request_sock_slab:
3193 req_prot_cleanup(prot->rsk_prot);
3195 kmem_cache_destroy(prot->slab);
3196 prot->slab = NULL;
3197 out:
3198 return -ENOBUFS;
3200 EXPORT_SYMBOL(proto_register);
3202 void proto_unregister(struct proto *prot)
3204 mutex_lock(&proto_list_mutex);
3205 release_proto_idx(prot);
3206 list_del(&prot->node);
3207 mutex_unlock(&proto_list_mutex);
3209 kmem_cache_destroy(prot->slab);
3210 prot->slab = NULL;
3212 req_prot_cleanup(prot->rsk_prot);
3214 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3215 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3216 kfree(prot->twsk_prot->twsk_slab_name);
3217 prot->twsk_prot->twsk_slab = NULL;
3220 EXPORT_SYMBOL(proto_unregister);
3222 #ifdef CONFIG_PROC_FS
3223 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3224 __acquires(proto_list_mutex)
3226 mutex_lock(&proto_list_mutex);
3227 return seq_list_start_head(&proto_list, *pos);
3230 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3232 return seq_list_next(v, &proto_list, pos);
3235 static void proto_seq_stop(struct seq_file *seq, void *v)
3236 __releases(proto_list_mutex)
3238 mutex_unlock(&proto_list_mutex);
3241 static char proto_method_implemented(const void *method)
3243 return method == NULL ? 'n' : 'y';
3245 static long sock_prot_memory_allocated(struct proto *proto)
3247 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3250 static char *sock_prot_memory_pressure(struct proto *proto)
3252 return proto->memory_pressure != NULL ?
3253 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3256 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3259 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
3260 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3261 proto->name,
3262 proto->obj_size,
3263 sock_prot_inuse_get(seq_file_net(seq), proto),
3264 sock_prot_memory_allocated(proto),
3265 sock_prot_memory_pressure(proto),
3266 proto->max_header,
3267 proto->slab == NULL ? "no" : "yes",
3268 module_name(proto->owner),
3269 proto_method_implemented(proto->close),
3270 proto_method_implemented(proto->connect),
3271 proto_method_implemented(proto->disconnect),
3272 proto_method_implemented(proto->accept),
3273 proto_method_implemented(proto->ioctl),
3274 proto_method_implemented(proto->init),
3275 proto_method_implemented(proto->destroy),
3276 proto_method_implemented(proto->shutdown),
3277 proto_method_implemented(proto->setsockopt),
3278 proto_method_implemented(proto->getsockopt),
3279 proto_method_implemented(proto->sendmsg),
3280 proto_method_implemented(proto->recvmsg),
3281 proto_method_implemented(proto->sendpage),
3282 proto_method_implemented(proto->bind),
3283 proto_method_implemented(proto->backlog_rcv),
3284 proto_method_implemented(proto->hash),
3285 proto_method_implemented(proto->unhash),
3286 proto_method_implemented(proto->get_port),
3287 proto_method_implemented(proto->enter_memory_pressure));
3290 static int proto_seq_show(struct seq_file *seq, void *v)
3292 if (v == &proto_list)
3293 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3294 "protocol",
3295 "size",
3296 "sockets",
3297 "memory",
3298 "press",
3299 "maxhdr",
3300 "slab",
3301 "module",
3302 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3303 else
3304 proto_seq_printf(seq, list_entry(v, struct proto, node));
3305 return 0;
3308 static const struct seq_operations proto_seq_ops = {
3309 .start = proto_seq_start,
3310 .next = proto_seq_next,
3311 .stop = proto_seq_stop,
3312 .show = proto_seq_show,
3315 static int proto_seq_open(struct inode *inode, struct file *file)
3317 return seq_open_net(inode, file, &proto_seq_ops,
3318 sizeof(struct seq_net_private));
3321 static const struct file_operations proto_seq_fops = {
3322 .owner = THIS_MODULE,
3323 .open = proto_seq_open,
3324 .read = seq_read,
3325 .llseek = seq_lseek,
3326 .release = seq_release_net,
3329 static __net_init int proto_init_net(struct net *net)
3331 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3332 return -ENOMEM;
3334 return 0;
3337 static __net_exit void proto_exit_net(struct net *net)
3339 remove_proc_entry("protocols", net->proc_net);
3343 static __net_initdata struct pernet_operations proto_net_ops = {
3344 .init = proto_init_net,
3345 .exit = proto_exit_net,
3348 static int __init proto_init(void)
3350 return register_pernet_subsys(&proto_net_ops);
3353 subsys_initcall(proto_init);
3355 #endif /* PROC_FS */
3357 #ifdef CONFIG_NET_RX_BUSY_POLL
3358 bool sk_busy_loop_end(void *p, unsigned long start_time)
3360 struct sock *sk = p;
3362 return !skb_queue_empty(&sk->sk_receive_queue) ||
3363 sk_busy_loop_timeout(sk, start_time);
3365 EXPORT_SYMBOL(sk_busy_loop_end);
3366 #endif /* CONFIG_NET_RX_BUSY_POLL */