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/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>
121
122 #include <linux/uaccess.h>
123
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>
136
137 #include <linux/filter.h>
138 #include <net/sock_reuseport.h>
139
140 #include <trace/events/sock.h>
141
142 #include <net/tcp.h>
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 */
sk_ns_capable(const struct sock * sk,struct user_namespace * user_ns,int cap)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 */
sk_capable(const struct sock * sk,int cap)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 */
sk_net_capable(const struct sock * sk,int cap)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 * 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.
200 */
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];
205
206 /*
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):
210 */
211
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"
228
229 static const char *const af_family_key_strings[AF_MAX+1] = {
230 _sock_locks("sk_lock-")
231 };
232 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
233 _sock_locks("slock-")
234 };
235 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
236 _sock_locks("clock-")
237 };
238
239 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
240 _sock_locks("k-sk_lock-")
241 };
242 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
243 _sock_locks("k-slock-")
244 };
245 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
246 _sock_locks("k-clock-")
247 };
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"
264 };
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"
281 };
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"
298 };
299
300 /*
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:
303 */
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];
309
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;
317
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);
321
322 int sysctl_tstamp_allow_data __read_mostly = 1;
323
324 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
325 EXPORT_SYMBOL_GPL(memalloc_socks);
326
327 /**
328 * sk_set_memalloc - sets %SOCK_MEMALLOC
329 * @sk: socket to set it on
330 *
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
334 */
sk_set_memalloc(struct sock * sk)335 void sk_set_memalloc(struct sock *sk)
336 {
337 sock_set_flag(sk, SOCK_MEMALLOC);
338 sk->sk_allocation |= __GFP_MEMALLOC;
339 static_key_slow_inc(&memalloc_socks);
340 }
341 EXPORT_SYMBOL_GPL(sk_set_memalloc);
342
sk_clear_memalloc(struct sock * sk)343 void sk_clear_memalloc(struct sock *sk)
344 {
345 sock_reset_flag(sk, SOCK_MEMALLOC);
346 sk->sk_allocation &= ~__GFP_MEMALLOC;
347 static_key_slow_dec(&memalloc_socks);
348
349 /*
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.
355 */
356 sk_mem_reclaim(sk);
357 }
358 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
359
__sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)360 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
361 {
362 int ret;
363 unsigned int noreclaim_flag;
364
365 /* these should have been dropped before queueing */
366 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
367
368 noreclaim_flag = memalloc_noreclaim_save();
369 ret = sk->sk_backlog_rcv(sk, skb);
370 memalloc_noreclaim_restore(noreclaim_flag);
371
372 return ret;
373 }
374 EXPORT_SYMBOL(__sk_backlog_rcv);
375
sock_set_timeout(long * timeo_p,char __user * optval,int optlen)376 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
377 {
378 struct timeval tv;
379
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;
386
387 if (tv.tv_sec < 0) {
388 static int warned __read_mostly;
389
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));
395 }
396 return 0;
397 }
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;
404 }
405
sock_warn_obsolete_bsdism(const char * name)406 static void sock_warn_obsolete_bsdism(const char *name)
407 {
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++;
415 }
416 }
417
sock_needs_netstamp(const struct sock * sk)418 static bool sock_needs_netstamp(const struct sock *sk)
419 {
420 switch (sk->sk_family) {
421 case AF_UNSPEC:
422 case AF_UNIX:
423 return false;
424 default:
425 return true;
426 }
427 }
428
sock_disable_timestamp(struct sock * sk,unsigned long flags)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 (sock_needs_netstamp(sk) &&
434 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
435 net_disable_timestamp();
436 }
437 }
438
439
__sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)440 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
441 {
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 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
452 atomic_inc(&sk->sk_drops);
453 return -ENOBUFS;
454 }
455
456 skb->dev = NULL;
457 skb_set_owner_r(skb, sk);
458
459 /* we escape from rcu protected region, make sure we dont leak
460 * a norefcounted dst
461 */
462 skb_dst_force(skb);
463
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);
468
469 if (!sock_flag(sk, SOCK_DEAD))
470 sk->sk_data_ready(sk);
471 return 0;
472 }
473 EXPORT_SYMBOL(__sock_queue_rcv_skb);
474
sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)475 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
476 {
477 int err;
478
479 err = sk_filter(sk, skb);
480 if (err)
481 return err;
482
483 return __sock_queue_rcv_skb(sk, skb);
484 }
485 EXPORT_SYMBOL(sock_queue_rcv_skb);
486
__sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested,unsigned int trim_cap,bool refcounted)487 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
488 const int nested, unsigned int trim_cap, bool refcounted)
489 {
490 int rc = NET_RX_SUCCESS;
491
492 if (sk_filter_trim_cap(sk, skb, trim_cap))
493 goto discard_and_relse;
494
495 skb->dev = NULL;
496
497 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
498 atomic_inc(&sk->sk_drops);
499 goto discard_and_relse;
500 }
501 if (nested)
502 bh_lock_sock_nested(sk);
503 else
504 bh_lock_sock(sk);
505 if (!sock_owned_by_user(sk)) {
506 /*
507 * trylock + unlock semantics:
508 */
509 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
510
511 rc = sk_backlog_rcv(sk, skb);
512
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;
518 }
519
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;
528 }
529 EXPORT_SYMBOL(__sk_receive_skb);
530
__sk_dst_check(struct sock * sk,u32 cookie)531 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
532 {
533 struct dst_entry *dst = __sk_dst_get(sk);
534
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;
541 }
542
543 return dst;
544 }
545 EXPORT_SYMBOL(__sk_dst_check);
546
sk_dst_check(struct sock * sk,u32 cookie)547 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
548 {
549 struct dst_entry *dst = sk_dst_get(sk);
550
551 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
552 sk_dst_reset(sk);
553 dst_release(dst);
554 return NULL;
555 }
556
557 return dst;
558 }
559 EXPORT_SYMBOL(sk_dst_check);
560
sock_setbindtodevice(struct sock * sk,char __user * optval,int optlen)561 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
562 int optlen)
563 {
564 int ret = -ENOPROTOOPT;
565 #ifdef CONFIG_NETDEVICES
566 struct net *net = sock_net(sk);
567 char devname[IFNAMSIZ];
568 int index;
569
570 /* Sorry... */
571 ret = -EPERM;
572 if (!ns_capable(net->user_ns, CAP_NET_RAW))
573 goto out;
574
575 ret = -EINVAL;
576 if (optlen < 0)
577 goto out;
578
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.
583 */
584 if (optlen > IFNAMSIZ - 1)
585 optlen = IFNAMSIZ - 1;
586 memset(devname, 0, sizeof(devname));
587
588 ret = -EFAULT;
589 if (copy_from_user(devname, optval, optlen))
590 goto out;
591
592 index = 0;
593 if (devname[0] != '\0') {
594 struct net_device *dev;
595
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;
604 }
605
606 lock_sock(sk);
607 sk->sk_bound_dev_if = index;
608 sk_dst_reset(sk);
609 release_sock(sk);
610
611 ret = 0;
612
613 out:
614 #endif
615
616 return ret;
617 }
618
sock_getbindtodevice(struct sock * sk,char __user * optval,int __user * optlen,int len)619 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
620 int __user *optlen, int len)
621 {
622 int ret = -ENOPROTOOPT;
623 #ifdef CONFIG_NETDEVICES
624 struct net *net = sock_net(sk);
625 char devname[IFNAMSIZ];
626
627 if (sk->sk_bound_dev_if == 0) {
628 len = 0;
629 goto zero;
630 }
631
632 ret = -EINVAL;
633 if (len < IFNAMSIZ)
634 goto out;
635
636 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
637 if (ret)
638 goto out;
639
640 len = strlen(devname) + 1;
641
642 ret = -EFAULT;
643 if (copy_to_user(optval, devname, len))
644 goto out;
645
646 zero:
647 ret = -EFAULT;
648 if (put_user(len, optlen))
649 goto out;
650
651 ret = 0;
652
653 out:
654 #endif
655
656 return ret;
657 }
658
sock_valbool_flag(struct sock * sk,int bit,int valbool)659 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
660 {
661 if (valbool)
662 sock_set_flag(sk, bit);
663 else
664 sock_reset_flag(sk, bit);
665 }
666
sk_mc_loop(struct sock * sk)667 bool sk_mc_loop(struct sock *sk)
668 {
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
680 }
681 WARN_ON(1);
682 return true;
683 }
684 EXPORT_SYMBOL(sk_mc_loop);
685
686 /*
687 * This is meant for all protocols to use and covers goings on
688 * at the socket level. Everything here is generic.
689 */
690
sock_setsockopt(struct socket * sock,int level,int optname,char __user * optval,unsigned int optlen)691 int sock_setsockopt(struct socket *sock, int level, int optname,
692 char __user *optval, unsigned int optlen)
693 {
694 struct sock *sk = sock->sk;
695 int val;
696 int valbool;
697 struct linger ling;
698 int ret = 0;
699
700 /*
701 * Options without arguments
702 */
703
704 if (optname == SO_BINDTODEVICE)
705 return sock_setbindtodevice(sk, optval, optlen);
706
707 if (optlen < sizeof(int))
708 return -EINVAL;
709
710 if (get_user(val, (int __user *)optval))
711 return -EFAULT;
712
713 valbool = val ? 1 : 0;
714
715 lock_sock(sk);
716
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 sk_dst_reset(sk);
739 break;
740 case SO_BROADCAST:
741 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
742 break;
743 case SO_SNDBUF:
744 /* Don't error on this BSD doesn't and if you think
745 * about it this is right. Otherwise apps have to
746 * play 'guess the biggest size' games. RCVBUF/SNDBUF
747 * are treated in BSD as hints
748 */
749 val = min_t(u32, val, sysctl_wmem_max);
750 set_sndbuf:
751 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
752 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
753 /* Wake up sending tasks if we upped the value. */
754 sk->sk_write_space(sk);
755 break;
756
757 case SO_SNDBUFFORCE:
758 if (!capable(CAP_NET_ADMIN)) {
759 ret = -EPERM;
760 break;
761 }
762 goto set_sndbuf;
763
764 case SO_RCVBUF:
765 /* Don't error on this BSD doesn't and if you think
766 * about it this is right. Otherwise apps have to
767 * play 'guess the biggest size' games. RCVBUF/SNDBUF
768 * are treated in BSD as hints
769 */
770 val = min_t(u32, val, sysctl_rmem_max);
771 set_rcvbuf:
772 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
773 /*
774 * We double it on the way in to account for
775 * "struct sk_buff" etc. overhead. Applications
776 * assume that the SO_RCVBUF setting they make will
777 * allow that much actual data to be received on that
778 * socket.
779 *
780 * Applications are unaware that "struct sk_buff" and
781 * other overheads allocate from the receive buffer
782 * during socket buffer allocation.
783 *
784 * And after considering the possible alternatives,
785 * returning the value we actually used in getsockopt
786 * is the most desirable behavior.
787 */
788 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
789 break;
790
791 case SO_RCVBUFFORCE:
792 if (!capable(CAP_NET_ADMIN)) {
793 ret = -EPERM;
794 break;
795 }
796 goto set_rcvbuf;
797
798 case SO_KEEPALIVE:
799 if (sk->sk_prot->keepalive)
800 sk->sk_prot->keepalive(sk, valbool);
801 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
802 break;
803
804 case SO_OOBINLINE:
805 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
806 break;
807
808 case SO_NO_CHECK:
809 sk->sk_no_check_tx = valbool;
810 break;
811
812 case SO_PRIORITY:
813 if ((val >= 0 && val <= 6) ||
814 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
815 sk->sk_priority = val;
816 else
817 ret = -EPERM;
818 break;
819
820 case SO_LINGER:
821 if (optlen < sizeof(ling)) {
822 ret = -EINVAL; /* 1003.1g */
823 break;
824 }
825 if (copy_from_user(&ling, optval, sizeof(ling))) {
826 ret = -EFAULT;
827 break;
828 }
829 if (!ling.l_onoff)
830 sock_reset_flag(sk, SOCK_LINGER);
831 else {
832 #if (BITS_PER_LONG == 32)
833 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
834 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
835 else
836 #endif
837 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
838 sock_set_flag(sk, SOCK_LINGER);
839 }
840 break;
841
842 case SO_BSDCOMPAT:
843 sock_warn_obsolete_bsdism("setsockopt");
844 break;
845
846 case SO_PASSCRED:
847 if (valbool)
848 set_bit(SOCK_PASSCRED, &sock->flags);
849 else
850 clear_bit(SOCK_PASSCRED, &sock->flags);
851 break;
852
853 case SO_TIMESTAMP:
854 case SO_TIMESTAMPNS:
855 if (valbool) {
856 if (optname == SO_TIMESTAMP)
857 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
858 else
859 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
860 sock_set_flag(sk, SOCK_RCVTSTAMP);
861 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
862 } else {
863 sock_reset_flag(sk, SOCK_RCVTSTAMP);
864 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
865 }
866 break;
867
868 case SO_TIMESTAMPING:
869 if (val & ~SOF_TIMESTAMPING_MASK) {
870 ret = -EINVAL;
871 break;
872 }
873
874 if (val & SOF_TIMESTAMPING_OPT_ID &&
875 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
876 if (sk->sk_protocol == IPPROTO_TCP &&
877 sk->sk_type == SOCK_STREAM) {
878 if ((1 << sk->sk_state) &
879 (TCPF_CLOSE | TCPF_LISTEN)) {
880 ret = -EINVAL;
881 break;
882 }
883 sk->sk_tskey = tcp_sk(sk)->snd_una;
884 } else {
885 sk->sk_tskey = 0;
886 }
887 }
888
889 if (val & SOF_TIMESTAMPING_OPT_STATS &&
890 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
891 ret = -EINVAL;
892 break;
893 }
894
895 sk->sk_tsflags = val;
896 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
897 sock_enable_timestamp(sk,
898 SOCK_TIMESTAMPING_RX_SOFTWARE);
899 else
900 sock_disable_timestamp(sk,
901 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
902 break;
903
904 case SO_RCVLOWAT:
905 if (val < 0)
906 val = INT_MAX;
907 sk->sk_rcvlowat = val ? : 1;
908 break;
909
910 case SO_RCVTIMEO:
911 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
912 break;
913
914 case SO_SNDTIMEO:
915 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
916 break;
917
918 case SO_ATTACH_FILTER:
919 ret = -EINVAL;
920 if (optlen == sizeof(struct sock_fprog)) {
921 struct sock_fprog fprog;
922
923 ret = -EFAULT;
924 if (copy_from_user(&fprog, optval, sizeof(fprog)))
925 break;
926
927 ret = sk_attach_filter(&fprog, sk);
928 }
929 break;
930
931 case SO_ATTACH_BPF:
932 ret = -EINVAL;
933 if (optlen == sizeof(u32)) {
934 u32 ufd;
935
936 ret = -EFAULT;
937 if (copy_from_user(&ufd, optval, sizeof(ufd)))
938 break;
939
940 ret = sk_attach_bpf(ufd, sk);
941 }
942 break;
943
944 case SO_ATTACH_REUSEPORT_CBPF:
945 ret = -EINVAL;
946 if (optlen == sizeof(struct sock_fprog)) {
947 struct sock_fprog fprog;
948
949 ret = -EFAULT;
950 if (copy_from_user(&fprog, optval, sizeof(fprog)))
951 break;
952
953 ret = sk_reuseport_attach_filter(&fprog, sk);
954 }
955 break;
956
957 case SO_ATTACH_REUSEPORT_EBPF:
958 ret = -EINVAL;
959 if (optlen == sizeof(u32)) {
960 u32 ufd;
961
962 ret = -EFAULT;
963 if (copy_from_user(&ufd, optval, sizeof(ufd)))
964 break;
965
966 ret = sk_reuseport_attach_bpf(ufd, sk);
967 }
968 break;
969
970 case SO_DETACH_FILTER:
971 ret = sk_detach_filter(sk);
972 break;
973
974 case SO_LOCK_FILTER:
975 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
976 ret = -EPERM;
977 else
978 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
979 break;
980
981 case SO_PASSSEC:
982 if (valbool)
983 set_bit(SOCK_PASSSEC, &sock->flags);
984 else
985 clear_bit(SOCK_PASSSEC, &sock->flags);
986 break;
987 case SO_MARK:
988 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
989 ret = -EPERM;
990 else
991 sk->sk_mark = val;
992 break;
993
994 case SO_RXQ_OVFL:
995 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
996 break;
997
998 case SO_WIFI_STATUS:
999 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1000 break;
1001
1002 case SO_PEEK_OFF:
1003 if (sock->ops->set_peek_off)
1004 ret = sock->ops->set_peek_off(sk, val);
1005 else
1006 ret = -EOPNOTSUPP;
1007 break;
1008
1009 case SO_NOFCS:
1010 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1011 break;
1012
1013 case SO_SELECT_ERR_QUEUE:
1014 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1015 break;
1016
1017 #ifdef CONFIG_NET_RX_BUSY_POLL
1018 case SO_BUSY_POLL:
1019 /* allow unprivileged users to decrease the value */
1020 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1021 ret = -EPERM;
1022 else {
1023 if (val < 0)
1024 ret = -EINVAL;
1025 else
1026 sk->sk_ll_usec = val;
1027 }
1028 break;
1029 #endif
1030
1031 case SO_MAX_PACING_RATE:
1032 if (val != ~0U)
1033 cmpxchg(&sk->sk_pacing_status,
1034 SK_PACING_NONE,
1035 SK_PACING_NEEDED);
1036 sk->sk_max_pacing_rate = val;
1037 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1038 sk->sk_max_pacing_rate);
1039 break;
1040
1041 case SO_INCOMING_CPU:
1042 WRITE_ONCE(sk->sk_incoming_cpu, val);
1043 break;
1044
1045 case SO_CNX_ADVICE:
1046 if (val == 1)
1047 dst_negative_advice(sk);
1048 break;
1049
1050 case SO_ZEROCOPY:
1051 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
1052 ret = -ENOTSUPP;
1053 else if (sk->sk_protocol != IPPROTO_TCP)
1054 ret = -ENOTSUPP;
1055 else if (sk->sk_state != TCP_CLOSE)
1056 ret = -EBUSY;
1057 else if (val < 0 || val > 1)
1058 ret = -EINVAL;
1059 else
1060 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1061 break;
1062
1063 default:
1064 ret = -ENOPROTOOPT;
1065 break;
1066 }
1067 release_sock(sk);
1068 return ret;
1069 }
1070 EXPORT_SYMBOL(sock_setsockopt);
1071
1072
cred_to_ucred(struct pid * pid,const struct cred * cred,struct ucred * ucred)1073 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1074 struct ucred *ucred)
1075 {
1076 ucred->pid = pid_vnr(pid);
1077 ucred->uid = ucred->gid = -1;
1078 if (cred) {
1079 struct user_namespace *current_ns = current_user_ns();
1080
1081 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1082 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1083 }
1084 }
1085
groups_to_user(gid_t __user * dst,const struct group_info * src)1086 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1087 {
1088 struct user_namespace *user_ns = current_user_ns();
1089 int i;
1090
1091 for (i = 0; i < src->ngroups; i++)
1092 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1093 return -EFAULT;
1094
1095 return 0;
1096 }
1097
sock_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)1098 int sock_getsockopt(struct socket *sock, int level, int optname,
1099 char __user *optval, int __user *optlen)
1100 {
1101 struct sock *sk = sock->sk;
1102
1103 union {
1104 int val;
1105 u64 val64;
1106 struct linger ling;
1107 struct timeval tm;
1108 } v;
1109
1110 int lv = sizeof(int);
1111 int len;
1112
1113 if (get_user(len, optlen))
1114 return -EFAULT;
1115 if (len < 0)
1116 return -EINVAL;
1117
1118 memset(&v, 0, sizeof(v));
1119
1120 switch (optname) {
1121 case SO_DEBUG:
1122 v.val = sock_flag(sk, SOCK_DBG);
1123 break;
1124
1125 case SO_DONTROUTE:
1126 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1127 break;
1128
1129 case SO_BROADCAST:
1130 v.val = sock_flag(sk, SOCK_BROADCAST);
1131 break;
1132
1133 case SO_SNDBUF:
1134 v.val = sk->sk_sndbuf;
1135 break;
1136
1137 case SO_RCVBUF:
1138 v.val = sk->sk_rcvbuf;
1139 break;
1140
1141 case SO_REUSEADDR:
1142 v.val = sk->sk_reuse;
1143 break;
1144
1145 case SO_REUSEPORT:
1146 v.val = sk->sk_reuseport;
1147 break;
1148
1149 case SO_KEEPALIVE:
1150 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1151 break;
1152
1153 case SO_TYPE:
1154 v.val = sk->sk_type;
1155 break;
1156
1157 case SO_PROTOCOL:
1158 v.val = sk->sk_protocol;
1159 break;
1160
1161 case SO_DOMAIN:
1162 v.val = sk->sk_family;
1163 break;
1164
1165 case SO_ERROR:
1166 v.val = -sock_error(sk);
1167 if (v.val == 0)
1168 v.val = xchg(&sk->sk_err_soft, 0);
1169 break;
1170
1171 case SO_OOBINLINE:
1172 v.val = sock_flag(sk, SOCK_URGINLINE);
1173 break;
1174
1175 case SO_NO_CHECK:
1176 v.val = sk->sk_no_check_tx;
1177 break;
1178
1179 case SO_PRIORITY:
1180 v.val = sk->sk_priority;
1181 break;
1182
1183 case SO_LINGER:
1184 lv = sizeof(v.ling);
1185 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1186 v.ling.l_linger = sk->sk_lingertime / HZ;
1187 break;
1188
1189 case SO_BSDCOMPAT:
1190 sock_warn_obsolete_bsdism("getsockopt");
1191 break;
1192
1193 case SO_TIMESTAMP:
1194 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1195 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1196 break;
1197
1198 case SO_TIMESTAMPNS:
1199 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1200 break;
1201
1202 case SO_TIMESTAMPING:
1203 v.val = sk->sk_tsflags;
1204 break;
1205
1206 case SO_RCVTIMEO:
1207 lv = sizeof(struct timeval);
1208 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1209 v.tm.tv_sec = 0;
1210 v.tm.tv_usec = 0;
1211 } else {
1212 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1213 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
1214 }
1215 break;
1216
1217 case SO_SNDTIMEO:
1218 lv = sizeof(struct timeval);
1219 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1220 v.tm.tv_sec = 0;
1221 v.tm.tv_usec = 0;
1222 } else {
1223 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1224 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1225 }
1226 break;
1227
1228 case SO_RCVLOWAT:
1229 v.val = sk->sk_rcvlowat;
1230 break;
1231
1232 case SO_SNDLOWAT:
1233 v.val = 1;
1234 break;
1235
1236 case SO_PASSCRED:
1237 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1238 break;
1239
1240 case SO_PEERCRED:
1241 {
1242 struct ucred peercred;
1243 if (len > sizeof(peercred))
1244 len = sizeof(peercred);
1245 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1246 if (copy_to_user(optval, &peercred, len))
1247 return -EFAULT;
1248 goto lenout;
1249 }
1250
1251 case SO_PEERGROUPS:
1252 {
1253 int ret, n;
1254
1255 if (!sk->sk_peer_cred)
1256 return -ENODATA;
1257
1258 n = sk->sk_peer_cred->group_info->ngroups;
1259 if (len < n * sizeof(gid_t)) {
1260 len = n * sizeof(gid_t);
1261 return put_user(len, optlen) ? -EFAULT : -ERANGE;
1262 }
1263 len = n * sizeof(gid_t);
1264
1265 ret = groups_to_user((gid_t __user *)optval,
1266 sk->sk_peer_cred->group_info);
1267 if (ret)
1268 return ret;
1269 goto lenout;
1270 }
1271
1272 case SO_PEERNAME:
1273 {
1274 char address[128];
1275
1276 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1277 return -ENOTCONN;
1278 if (lv < len)
1279 return -EINVAL;
1280 if (copy_to_user(optval, address, len))
1281 return -EFAULT;
1282 goto lenout;
1283 }
1284
1285 /* Dubious BSD thing... Probably nobody even uses it, but
1286 * the UNIX standard wants it for whatever reason... -DaveM
1287 */
1288 case SO_ACCEPTCONN:
1289 v.val = sk->sk_state == TCP_LISTEN;
1290 break;
1291
1292 case SO_PASSSEC:
1293 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1294 break;
1295
1296 case SO_PEERSEC:
1297 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1298
1299 case SO_MARK:
1300 v.val = sk->sk_mark;
1301 break;
1302
1303 case SO_RXQ_OVFL:
1304 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1305 break;
1306
1307 case SO_WIFI_STATUS:
1308 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1309 break;
1310
1311 case SO_PEEK_OFF:
1312 if (!sock->ops->set_peek_off)
1313 return -EOPNOTSUPP;
1314
1315 v.val = sk->sk_peek_off;
1316 break;
1317 case SO_NOFCS:
1318 v.val = sock_flag(sk, SOCK_NOFCS);
1319 break;
1320
1321 case SO_BINDTODEVICE:
1322 return sock_getbindtodevice(sk, optval, optlen, len);
1323
1324 case SO_GET_FILTER:
1325 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1326 if (len < 0)
1327 return len;
1328
1329 goto lenout;
1330
1331 case SO_LOCK_FILTER:
1332 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1333 break;
1334
1335 case SO_BPF_EXTENSIONS:
1336 v.val = bpf_tell_extensions();
1337 break;
1338
1339 case SO_SELECT_ERR_QUEUE:
1340 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1341 break;
1342
1343 #ifdef CONFIG_NET_RX_BUSY_POLL
1344 case SO_BUSY_POLL:
1345 v.val = sk->sk_ll_usec;
1346 break;
1347 #endif
1348
1349 case SO_MAX_PACING_RATE:
1350 v.val = sk->sk_max_pacing_rate;
1351 break;
1352
1353 case SO_INCOMING_CPU:
1354 v.val = READ_ONCE(sk->sk_incoming_cpu);
1355 break;
1356
1357 case SO_MEMINFO:
1358 {
1359 u32 meminfo[SK_MEMINFO_VARS];
1360
1361 sk_get_meminfo(sk, meminfo);
1362
1363 len = min_t(unsigned int, len, sizeof(meminfo));
1364 if (copy_to_user(optval, &meminfo, len))
1365 return -EFAULT;
1366
1367 goto lenout;
1368 }
1369
1370 #ifdef CONFIG_NET_RX_BUSY_POLL
1371 case SO_INCOMING_NAPI_ID:
1372 v.val = READ_ONCE(sk->sk_napi_id);
1373
1374 /* aggregate non-NAPI IDs down to 0 */
1375 if (v.val < MIN_NAPI_ID)
1376 v.val = 0;
1377
1378 break;
1379 #endif
1380
1381 case SO_COOKIE:
1382 lv = sizeof(u64);
1383 if (len < lv)
1384 return -EINVAL;
1385 v.val64 = sock_gen_cookie(sk);
1386 break;
1387
1388 case SO_ZEROCOPY:
1389 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1390 break;
1391
1392 default:
1393 /* We implement the SO_SNDLOWAT etc to not be settable
1394 * (1003.1g 7).
1395 */
1396 return -ENOPROTOOPT;
1397 }
1398
1399 if (len > lv)
1400 len = lv;
1401 if (copy_to_user(optval, &v, len))
1402 return -EFAULT;
1403 lenout:
1404 if (put_user(len, optlen))
1405 return -EFAULT;
1406 return 0;
1407 }
1408
1409 /*
1410 * Initialize an sk_lock.
1411 *
1412 * (We also register the sk_lock with the lock validator.)
1413 */
sock_lock_init(struct sock * sk)1414 static inline void sock_lock_init(struct sock *sk)
1415 {
1416 if (sk->sk_kern_sock)
1417 sock_lock_init_class_and_name(
1418 sk,
1419 af_family_kern_slock_key_strings[sk->sk_family],
1420 af_family_kern_slock_keys + sk->sk_family,
1421 af_family_kern_key_strings[sk->sk_family],
1422 af_family_kern_keys + sk->sk_family);
1423 else
1424 sock_lock_init_class_and_name(
1425 sk,
1426 af_family_slock_key_strings[sk->sk_family],
1427 af_family_slock_keys + sk->sk_family,
1428 af_family_key_strings[sk->sk_family],
1429 af_family_keys + sk->sk_family);
1430 }
1431
1432 /*
1433 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1434 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1435 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1436 */
sock_copy(struct sock * nsk,const struct sock * osk)1437 static void sock_copy(struct sock *nsk, const struct sock *osk)
1438 {
1439 #ifdef CONFIG_SECURITY_NETWORK
1440 void *sptr = nsk->sk_security;
1441 #endif
1442 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1443
1444 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1445 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1446
1447 #ifdef CONFIG_SECURITY_NETWORK
1448 nsk->sk_security = sptr;
1449 security_sk_clone(osk, nsk);
1450 #endif
1451 }
1452
sk_prot_alloc(struct proto * prot,gfp_t priority,int family)1453 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1454 int family)
1455 {
1456 struct sock *sk;
1457 struct kmem_cache *slab;
1458
1459 slab = prot->slab;
1460 if (slab != NULL) {
1461 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1462 if (!sk)
1463 return sk;
1464 if (priority & __GFP_ZERO)
1465 sk_prot_clear_nulls(sk, prot->obj_size);
1466 } else
1467 sk = kmalloc(prot->obj_size, priority);
1468
1469 if (sk != NULL) {
1470 if (security_sk_alloc(sk, family, priority))
1471 goto out_free;
1472
1473 if (!try_module_get(prot->owner))
1474 goto out_free_sec;
1475 sk_tx_queue_clear(sk);
1476 }
1477
1478 return sk;
1479
1480 out_free_sec:
1481 security_sk_free(sk);
1482 out_free:
1483 if (slab != NULL)
1484 kmem_cache_free(slab, sk);
1485 else
1486 kfree(sk);
1487 return NULL;
1488 }
1489
sk_prot_free(struct proto * prot,struct sock * sk)1490 static void sk_prot_free(struct proto *prot, struct sock *sk)
1491 {
1492 struct kmem_cache *slab;
1493 struct module *owner;
1494
1495 owner = prot->owner;
1496 slab = prot->slab;
1497
1498 cgroup_sk_free(&sk->sk_cgrp_data);
1499 mem_cgroup_sk_free(sk);
1500 security_sk_free(sk);
1501 if (slab != NULL)
1502 kmem_cache_free(slab, sk);
1503 else
1504 kfree(sk);
1505 module_put(owner);
1506 }
1507
1508 /**
1509 * sk_alloc - All socket objects are allocated here
1510 * @net: the applicable net namespace
1511 * @family: protocol family
1512 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1513 * @prot: struct proto associated with this new sock instance
1514 * @kern: is this to be a kernel socket?
1515 */
sk_alloc(struct net * net,int family,gfp_t priority,struct proto * prot,int kern)1516 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1517 struct proto *prot, int kern)
1518 {
1519 struct sock *sk;
1520
1521 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1522 if (sk) {
1523 sk->sk_family = family;
1524 /*
1525 * See comment in struct sock definition to understand
1526 * why we need sk_prot_creator -acme
1527 */
1528 sk->sk_prot = sk->sk_prot_creator = prot;
1529 sk->sk_kern_sock = kern;
1530 sock_lock_init(sk);
1531 sk->sk_net_refcnt = kern ? 0 : 1;
1532 if (likely(sk->sk_net_refcnt))
1533 get_net(net);
1534 sock_net_set(sk, net);
1535 refcount_set(&sk->sk_wmem_alloc, 1);
1536
1537 mem_cgroup_sk_alloc(sk);
1538 cgroup_sk_alloc(&sk->sk_cgrp_data);
1539 sock_update_classid(&sk->sk_cgrp_data);
1540 sock_update_netprioidx(&sk->sk_cgrp_data);
1541 }
1542
1543 return sk;
1544 }
1545 EXPORT_SYMBOL(sk_alloc);
1546
1547 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1548 * grace period. This is the case for UDP sockets and TCP listeners.
1549 */
__sk_destruct(struct rcu_head * head)1550 static void __sk_destruct(struct rcu_head *head)
1551 {
1552 struct sock *sk = container_of(head, struct sock, sk_rcu);
1553 struct sk_filter *filter;
1554
1555 if (sk->sk_destruct)
1556 sk->sk_destruct(sk);
1557
1558 filter = rcu_dereference_check(sk->sk_filter,
1559 refcount_read(&sk->sk_wmem_alloc) == 0);
1560 if (filter) {
1561 sk_filter_uncharge(sk, filter);
1562 RCU_INIT_POINTER(sk->sk_filter, NULL);
1563 }
1564
1565 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1566
1567 if (atomic_read(&sk->sk_omem_alloc))
1568 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1569 __func__, atomic_read(&sk->sk_omem_alloc));
1570
1571 if (sk->sk_frag.page) {
1572 put_page(sk->sk_frag.page);
1573 sk->sk_frag.page = NULL;
1574 }
1575
1576 if (sk->sk_peer_cred)
1577 put_cred(sk->sk_peer_cred);
1578 put_pid(sk->sk_peer_pid);
1579 if (likely(sk->sk_net_refcnt))
1580 put_net(sock_net(sk));
1581 sk_prot_free(sk->sk_prot_creator, sk);
1582 }
1583
sk_destruct(struct sock * sk)1584 void sk_destruct(struct sock *sk)
1585 {
1586 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
1587
1588 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
1589 reuseport_detach_sock(sk);
1590 use_call_rcu = true;
1591 }
1592
1593 if (use_call_rcu)
1594 call_rcu(&sk->sk_rcu, __sk_destruct);
1595 else
1596 __sk_destruct(&sk->sk_rcu);
1597 }
1598
__sk_free(struct sock * sk)1599 static void __sk_free(struct sock *sk)
1600 {
1601 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1602 sock_diag_broadcast_destroy(sk);
1603 else
1604 sk_destruct(sk);
1605 }
1606
sk_free(struct sock * sk)1607 void sk_free(struct sock *sk)
1608 {
1609 /*
1610 * We subtract one from sk_wmem_alloc and can know if
1611 * some packets are still in some tx queue.
1612 * If not null, sock_wfree() will call __sk_free(sk) later
1613 */
1614 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1615 __sk_free(sk);
1616 }
1617 EXPORT_SYMBOL(sk_free);
1618
sk_init_common(struct sock * sk)1619 static void sk_init_common(struct sock *sk)
1620 {
1621 skb_queue_head_init(&sk->sk_receive_queue);
1622 skb_queue_head_init(&sk->sk_write_queue);
1623 skb_queue_head_init(&sk->sk_error_queue);
1624
1625 rwlock_init(&sk->sk_callback_lock);
1626 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1627 af_rlock_keys + sk->sk_family,
1628 af_family_rlock_key_strings[sk->sk_family]);
1629 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1630 af_wlock_keys + sk->sk_family,
1631 af_family_wlock_key_strings[sk->sk_family]);
1632 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1633 af_elock_keys + sk->sk_family,
1634 af_family_elock_key_strings[sk->sk_family]);
1635 lockdep_set_class_and_name(&sk->sk_callback_lock,
1636 af_callback_keys + sk->sk_family,
1637 af_family_clock_key_strings[sk->sk_family]);
1638 }
1639
1640 /**
1641 * sk_clone_lock - clone a socket, and lock its clone
1642 * @sk: the socket to clone
1643 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1644 *
1645 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1646 */
sk_clone_lock(const struct sock * sk,const gfp_t priority)1647 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1648 {
1649 struct sock *newsk;
1650 bool is_charged = true;
1651
1652 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1653 if (newsk != NULL) {
1654 struct sk_filter *filter;
1655
1656 sock_copy(newsk, sk);
1657
1658 newsk->sk_prot_creator = sk->sk_prot;
1659
1660 /* SANITY */
1661 if (likely(newsk->sk_net_refcnt))
1662 get_net(sock_net(newsk));
1663 sk_node_init(&newsk->sk_node);
1664 sock_lock_init(newsk);
1665 bh_lock_sock(newsk);
1666 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1667 newsk->sk_backlog.len = 0;
1668
1669 atomic_set(&newsk->sk_rmem_alloc, 0);
1670 /*
1671 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1672 */
1673 refcount_set(&newsk->sk_wmem_alloc, 1);
1674 atomic_set(&newsk->sk_omem_alloc, 0);
1675 sk_init_common(newsk);
1676
1677 newsk->sk_dst_cache = NULL;
1678 newsk->sk_dst_pending_confirm = 0;
1679 newsk->sk_wmem_queued = 0;
1680 newsk->sk_forward_alloc = 0;
1681 atomic_set(&newsk->sk_drops, 0);
1682 newsk->sk_send_head = NULL;
1683 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1684 atomic_set(&newsk->sk_zckey, 0);
1685
1686 sock_reset_flag(newsk, SOCK_DONE);
1687
1688 /* sk->sk_memcg will be populated at accept() time */
1689 newsk->sk_memcg = NULL;
1690
1691 cgroup_sk_alloc(&newsk->sk_cgrp_data);
1692
1693 rcu_read_lock();
1694 filter = rcu_dereference(sk->sk_filter);
1695 if (filter != NULL)
1696 /* though it's an empty new sock, the charging may fail
1697 * if sysctl_optmem_max was changed between creation of
1698 * original socket and cloning
1699 */
1700 is_charged = sk_filter_charge(newsk, filter);
1701 RCU_INIT_POINTER(newsk->sk_filter, filter);
1702 rcu_read_unlock();
1703
1704 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1705 /* We need to make sure that we don't uncharge the new
1706 * socket if we couldn't charge it in the first place
1707 * as otherwise we uncharge the parent's filter.
1708 */
1709 if (!is_charged)
1710 RCU_INIT_POINTER(newsk->sk_filter, NULL);
1711 sk_free_unlock_clone(newsk);
1712 newsk = NULL;
1713 goto out;
1714 }
1715 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1716
1717 newsk->sk_err = 0;
1718 newsk->sk_err_soft = 0;
1719 newsk->sk_priority = 0;
1720 newsk->sk_incoming_cpu = raw_smp_processor_id();
1721 atomic64_set(&newsk->sk_cookie, 0);
1722
1723 /*
1724 * Before updating sk_refcnt, we must commit prior changes to memory
1725 * (Documentation/RCU/rculist_nulls.txt for details)
1726 */
1727 smp_wmb();
1728 refcount_set(&newsk->sk_refcnt, 2);
1729
1730 /*
1731 * Increment the counter in the same struct proto as the master
1732 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1733 * is the same as sk->sk_prot->socks, as this field was copied
1734 * with memcpy).
1735 *
1736 * This _changes_ the previous behaviour, where
1737 * tcp_create_openreq_child always was incrementing the
1738 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1739 * to be taken into account in all callers. -acme
1740 */
1741 sk_refcnt_debug_inc(newsk);
1742 sk_set_socket(newsk, NULL);
1743 newsk->sk_wq = NULL;
1744
1745 if (newsk->sk_prot->sockets_allocated)
1746 sk_sockets_allocated_inc(newsk);
1747
1748 if (sock_needs_netstamp(sk) &&
1749 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1750 net_enable_timestamp();
1751 }
1752 out:
1753 return newsk;
1754 }
1755 EXPORT_SYMBOL_GPL(sk_clone_lock);
1756
sk_free_unlock_clone(struct sock * sk)1757 void sk_free_unlock_clone(struct sock *sk)
1758 {
1759 /* It is still raw copy of parent, so invalidate
1760 * destructor and make plain sk_free() */
1761 sk->sk_destruct = NULL;
1762 bh_unlock_sock(sk);
1763 sk_free(sk);
1764 }
1765 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1766
sk_setup_caps(struct sock * sk,struct dst_entry * dst)1767 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1768 {
1769 u32 max_segs = 1;
1770
1771 sk_dst_set(sk, dst);
1772 sk->sk_route_caps = dst->dev->features;
1773 if (sk->sk_route_caps & NETIF_F_GSO)
1774 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1775 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1776 if (sk_can_gso(sk)) {
1777 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1778 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1779 } else {
1780 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1781 sk->sk_gso_max_size = dst->dev->gso_max_size;
1782 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1783 }
1784 }
1785 sk->sk_gso_max_segs = max_segs;
1786 }
1787 EXPORT_SYMBOL_GPL(sk_setup_caps);
1788
1789 /*
1790 * Simple resource managers for sockets.
1791 */
1792
1793
1794 /*
1795 * Write buffer destructor automatically called from kfree_skb.
1796 */
sock_wfree(struct sk_buff * skb)1797 void sock_wfree(struct sk_buff *skb)
1798 {
1799 struct sock *sk = skb->sk;
1800 unsigned int len = skb->truesize;
1801
1802 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1803 /*
1804 * Keep a reference on sk_wmem_alloc, this will be released
1805 * after sk_write_space() call
1806 */
1807 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1808 sk->sk_write_space(sk);
1809 len = 1;
1810 }
1811 /*
1812 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1813 * could not do because of in-flight packets
1814 */
1815 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1816 __sk_free(sk);
1817 }
1818 EXPORT_SYMBOL(sock_wfree);
1819
1820 /* This variant of sock_wfree() is used by TCP,
1821 * since it sets SOCK_USE_WRITE_QUEUE.
1822 */
__sock_wfree(struct sk_buff * skb)1823 void __sock_wfree(struct sk_buff *skb)
1824 {
1825 struct sock *sk = skb->sk;
1826
1827 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1828 __sk_free(sk);
1829 }
1830
skb_set_owner_w(struct sk_buff * skb,struct sock * sk)1831 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1832 {
1833 skb_orphan(skb);
1834 skb->sk = sk;
1835 #ifdef CONFIG_INET
1836 if (unlikely(!sk_fullsock(sk))) {
1837 skb->destructor = sock_edemux;
1838 sock_hold(sk);
1839 return;
1840 }
1841 #endif
1842 skb->destructor = sock_wfree;
1843 skb_set_hash_from_sk(skb, sk);
1844 /*
1845 * We used to take a refcount on sk, but following operation
1846 * is enough to guarantee sk_free() wont free this sock until
1847 * all in-flight packets are completed
1848 */
1849 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1850 }
1851 EXPORT_SYMBOL(skb_set_owner_w);
1852
1853 /* This helper is used by netem, as it can hold packets in its
1854 * delay queue. We want to allow the owner socket to send more
1855 * packets, as if they were already TX completed by a typical driver.
1856 * But we also want to keep skb->sk set because some packet schedulers
1857 * rely on it (sch_fq for example).
1858 */
skb_orphan_partial(struct sk_buff * skb)1859 void skb_orphan_partial(struct sk_buff *skb)
1860 {
1861 if (skb_is_tcp_pure_ack(skb))
1862 return;
1863
1864 if (skb->destructor == sock_wfree
1865 #ifdef CONFIG_INET
1866 || skb->destructor == tcp_wfree
1867 #endif
1868 ) {
1869 struct sock *sk = skb->sk;
1870
1871 if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1872 WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
1873 skb->destructor = sock_efree;
1874 }
1875 } else {
1876 skb_orphan(skb);
1877 }
1878 }
1879 EXPORT_SYMBOL(skb_orphan_partial);
1880
1881 /*
1882 * Read buffer destructor automatically called from kfree_skb.
1883 */
sock_rfree(struct sk_buff * skb)1884 void sock_rfree(struct sk_buff *skb)
1885 {
1886 struct sock *sk = skb->sk;
1887 unsigned int len = skb->truesize;
1888
1889 atomic_sub(len, &sk->sk_rmem_alloc);
1890 sk_mem_uncharge(sk, len);
1891 }
1892 EXPORT_SYMBOL(sock_rfree);
1893
1894 /*
1895 * Buffer destructor for skbs that are not used directly in read or write
1896 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1897 */
sock_efree(struct sk_buff * skb)1898 void sock_efree(struct sk_buff *skb)
1899 {
1900 sock_put(skb->sk);
1901 }
1902 EXPORT_SYMBOL(sock_efree);
1903
sock_i_uid(struct sock * sk)1904 kuid_t sock_i_uid(struct sock *sk)
1905 {
1906 kuid_t uid;
1907
1908 read_lock_bh(&sk->sk_callback_lock);
1909 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1910 read_unlock_bh(&sk->sk_callback_lock);
1911 return uid;
1912 }
1913 EXPORT_SYMBOL(sock_i_uid);
1914
sock_i_ino(struct sock * sk)1915 unsigned long sock_i_ino(struct sock *sk)
1916 {
1917 unsigned long ino;
1918
1919 read_lock_bh(&sk->sk_callback_lock);
1920 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1921 read_unlock_bh(&sk->sk_callback_lock);
1922 return ino;
1923 }
1924 EXPORT_SYMBOL(sock_i_ino);
1925
1926 /*
1927 * Allocate a skb from the socket's send buffer.
1928 */
sock_wmalloc(struct sock * sk,unsigned long size,int force,gfp_t priority)1929 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1930 gfp_t priority)
1931 {
1932 if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1933 struct sk_buff *skb = alloc_skb(size, priority);
1934 if (skb) {
1935 skb_set_owner_w(skb, sk);
1936 return skb;
1937 }
1938 }
1939 return NULL;
1940 }
1941 EXPORT_SYMBOL(sock_wmalloc);
1942
sock_ofree(struct sk_buff * skb)1943 static void sock_ofree(struct sk_buff *skb)
1944 {
1945 struct sock *sk = skb->sk;
1946
1947 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
1948 }
1949
sock_omalloc(struct sock * sk,unsigned long size,gfp_t priority)1950 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1951 gfp_t priority)
1952 {
1953 struct sk_buff *skb;
1954
1955 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
1956 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
1957 sysctl_optmem_max)
1958 return NULL;
1959
1960 skb = alloc_skb(size, priority);
1961 if (!skb)
1962 return NULL;
1963
1964 atomic_add(skb->truesize, &sk->sk_omem_alloc);
1965 skb->sk = sk;
1966 skb->destructor = sock_ofree;
1967 return skb;
1968 }
1969
1970 /*
1971 * Allocate a memory block from the socket's option memory buffer.
1972 */
sock_kmalloc(struct sock * sk,int size,gfp_t priority)1973 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1974 {
1975 if ((unsigned int)size <= sysctl_optmem_max &&
1976 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1977 void *mem;
1978 /* First do the add, to avoid the race if kmalloc
1979 * might sleep.
1980 */
1981 atomic_add(size, &sk->sk_omem_alloc);
1982 mem = kmalloc(size, priority);
1983 if (mem)
1984 return mem;
1985 atomic_sub(size, &sk->sk_omem_alloc);
1986 }
1987 return NULL;
1988 }
1989 EXPORT_SYMBOL(sock_kmalloc);
1990
1991 /* Free an option memory block. Note, we actually want the inline
1992 * here as this allows gcc to detect the nullify and fold away the
1993 * condition entirely.
1994 */
__sock_kfree_s(struct sock * sk,void * mem,int size,const bool nullify)1995 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1996 const bool nullify)
1997 {
1998 if (WARN_ON_ONCE(!mem))
1999 return;
2000 if (nullify)
2001 kzfree(mem);
2002 else
2003 kfree(mem);
2004 atomic_sub(size, &sk->sk_omem_alloc);
2005 }
2006
sock_kfree_s(struct sock * sk,void * mem,int size)2007 void sock_kfree_s(struct sock *sk, void *mem, int size)
2008 {
2009 __sock_kfree_s(sk, mem, size, false);
2010 }
2011 EXPORT_SYMBOL(sock_kfree_s);
2012
sock_kzfree_s(struct sock * sk,void * mem,int size)2013 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2014 {
2015 __sock_kfree_s(sk, mem, size, true);
2016 }
2017 EXPORT_SYMBOL(sock_kzfree_s);
2018
2019 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2020 I think, these locks should be removed for datagram sockets.
2021 */
sock_wait_for_wmem(struct sock * sk,long timeo)2022 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2023 {
2024 DEFINE_WAIT(wait);
2025
2026 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2027 for (;;) {
2028 if (!timeo)
2029 break;
2030 if (signal_pending(current))
2031 break;
2032 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2033 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2034 if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2035 break;
2036 if (sk->sk_shutdown & SEND_SHUTDOWN)
2037 break;
2038 if (sk->sk_err)
2039 break;
2040 timeo = schedule_timeout(timeo);
2041 }
2042 finish_wait(sk_sleep(sk), &wait);
2043 return timeo;
2044 }
2045
2046
2047 /*
2048 * Generic send/receive buffer handlers
2049 */
2050
sock_alloc_send_pskb(struct sock * sk,unsigned long header_len,unsigned long data_len,int noblock,int * errcode,int max_page_order)2051 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2052 unsigned long data_len, int noblock,
2053 int *errcode, int max_page_order)
2054 {
2055 struct sk_buff *skb;
2056 long timeo;
2057 int err;
2058
2059 timeo = sock_sndtimeo(sk, noblock);
2060 for (;;) {
2061 err = sock_error(sk);
2062 if (err != 0)
2063 goto failure;
2064
2065 err = -EPIPE;
2066 if (sk->sk_shutdown & SEND_SHUTDOWN)
2067 goto failure;
2068
2069 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2070 break;
2071
2072 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2073 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2074 err = -EAGAIN;
2075 if (!timeo)
2076 goto failure;
2077 if (signal_pending(current))
2078 goto interrupted;
2079 timeo = sock_wait_for_wmem(sk, timeo);
2080 }
2081 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2082 errcode, sk->sk_allocation);
2083 if (skb)
2084 skb_set_owner_w(skb, sk);
2085 return skb;
2086
2087 interrupted:
2088 err = sock_intr_errno(timeo);
2089 failure:
2090 *errcode = err;
2091 return NULL;
2092 }
2093 EXPORT_SYMBOL(sock_alloc_send_pskb);
2094
sock_alloc_send_skb(struct sock * sk,unsigned long size,int noblock,int * errcode)2095 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2096 int noblock, int *errcode)
2097 {
2098 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2099 }
2100 EXPORT_SYMBOL(sock_alloc_send_skb);
2101
__sock_cmsg_send(struct sock * sk,struct msghdr * msg,struct cmsghdr * cmsg,struct sockcm_cookie * sockc)2102 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2103 struct sockcm_cookie *sockc)
2104 {
2105 u32 tsflags;
2106
2107 switch (cmsg->cmsg_type) {
2108 case SO_MARK:
2109 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2110 return -EPERM;
2111 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2112 return -EINVAL;
2113 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2114 break;
2115 case SO_TIMESTAMPING:
2116 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2117 return -EINVAL;
2118
2119 tsflags = *(u32 *)CMSG_DATA(cmsg);
2120 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2121 return -EINVAL;
2122
2123 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2124 sockc->tsflags |= tsflags;
2125 break;
2126 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2127 case SCM_RIGHTS:
2128 case SCM_CREDENTIALS:
2129 break;
2130 default:
2131 return -EINVAL;
2132 }
2133 return 0;
2134 }
2135 EXPORT_SYMBOL(__sock_cmsg_send);
2136
sock_cmsg_send(struct sock * sk,struct msghdr * msg,struct sockcm_cookie * sockc)2137 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2138 struct sockcm_cookie *sockc)
2139 {
2140 struct cmsghdr *cmsg;
2141 int ret;
2142
2143 for_each_cmsghdr(cmsg, msg) {
2144 if (!CMSG_OK(msg, cmsg))
2145 return -EINVAL;
2146 if (cmsg->cmsg_level != SOL_SOCKET)
2147 continue;
2148 ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2149 if (ret)
2150 return ret;
2151 }
2152 return 0;
2153 }
2154 EXPORT_SYMBOL(sock_cmsg_send);
2155
sk_enter_memory_pressure(struct sock * sk)2156 static void sk_enter_memory_pressure(struct sock *sk)
2157 {
2158 if (!sk->sk_prot->enter_memory_pressure)
2159 return;
2160
2161 sk->sk_prot->enter_memory_pressure(sk);
2162 }
2163
sk_leave_memory_pressure(struct sock * sk)2164 static void sk_leave_memory_pressure(struct sock *sk)
2165 {
2166 if (sk->sk_prot->leave_memory_pressure) {
2167 sk->sk_prot->leave_memory_pressure(sk);
2168 } else {
2169 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2170
2171 if (memory_pressure && READ_ONCE(*memory_pressure))
2172 WRITE_ONCE(*memory_pressure, 0);
2173 }
2174 }
2175
2176 /* On 32bit arches, an skb frag is limited to 2^15 */
2177 #define SKB_FRAG_PAGE_ORDER get_order(32768)
2178
2179 /**
2180 * skb_page_frag_refill - check that a page_frag contains enough room
2181 * @sz: minimum size of the fragment we want to get
2182 * @pfrag: pointer to page_frag
2183 * @gfp: priority for memory allocation
2184 *
2185 * Note: While this allocator tries to use high order pages, there is
2186 * no guarantee that allocations succeed. Therefore, @sz MUST be
2187 * less or equal than PAGE_SIZE.
2188 */
skb_page_frag_refill(unsigned int sz,struct page_frag * pfrag,gfp_t gfp)2189 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2190 {
2191 if (pfrag->page) {
2192 if (page_ref_count(pfrag->page) == 1) {
2193 pfrag->offset = 0;
2194 return true;
2195 }
2196 if (pfrag->offset + sz <= pfrag->size)
2197 return true;
2198 put_page(pfrag->page);
2199 }
2200
2201 pfrag->offset = 0;
2202 if (SKB_FRAG_PAGE_ORDER) {
2203 /* Avoid direct reclaim but allow kswapd to wake */
2204 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2205 __GFP_COMP | __GFP_NOWARN |
2206 __GFP_NORETRY,
2207 SKB_FRAG_PAGE_ORDER);
2208 if (likely(pfrag->page)) {
2209 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2210 return true;
2211 }
2212 }
2213 pfrag->page = alloc_page(gfp);
2214 if (likely(pfrag->page)) {
2215 pfrag->size = PAGE_SIZE;
2216 return true;
2217 }
2218 return false;
2219 }
2220 EXPORT_SYMBOL(skb_page_frag_refill);
2221
sk_page_frag_refill(struct sock * sk,struct page_frag * pfrag)2222 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2223 {
2224 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2225 return true;
2226
2227 sk_enter_memory_pressure(sk);
2228 sk_stream_moderate_sndbuf(sk);
2229 return false;
2230 }
2231 EXPORT_SYMBOL(sk_page_frag_refill);
2232
__lock_sock(struct sock * sk)2233 static void __lock_sock(struct sock *sk)
2234 __releases(&sk->sk_lock.slock)
2235 __acquires(&sk->sk_lock.slock)
2236 {
2237 DEFINE_WAIT(wait);
2238
2239 for (;;) {
2240 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2241 TASK_UNINTERRUPTIBLE);
2242 spin_unlock_bh(&sk->sk_lock.slock);
2243 schedule();
2244 spin_lock_bh(&sk->sk_lock.slock);
2245 if (!sock_owned_by_user(sk))
2246 break;
2247 }
2248 finish_wait(&sk->sk_lock.wq, &wait);
2249 }
2250
__release_sock(struct sock * sk)2251 void __release_sock(struct sock *sk)
2252 __releases(&sk->sk_lock.slock)
2253 __acquires(&sk->sk_lock.slock)
2254 {
2255 struct sk_buff *skb, *next;
2256
2257 while ((skb = sk->sk_backlog.head) != NULL) {
2258 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2259
2260 spin_unlock_bh(&sk->sk_lock.slock);
2261
2262 do {
2263 next = skb->next;
2264 prefetch(next);
2265 WARN_ON_ONCE(skb_dst_is_noref(skb));
2266 skb->next = NULL;
2267 sk_backlog_rcv(sk, skb);
2268
2269 cond_resched();
2270
2271 skb = next;
2272 } while (skb != NULL);
2273
2274 spin_lock_bh(&sk->sk_lock.slock);
2275 }
2276
2277 /*
2278 * Doing the zeroing here guarantee we can not loop forever
2279 * while a wild producer attempts to flood us.
2280 */
2281 sk->sk_backlog.len = 0;
2282 }
2283
__sk_flush_backlog(struct sock * sk)2284 void __sk_flush_backlog(struct sock *sk)
2285 {
2286 spin_lock_bh(&sk->sk_lock.slock);
2287 __release_sock(sk);
2288 spin_unlock_bh(&sk->sk_lock.slock);
2289 }
2290
2291 /**
2292 * sk_wait_data - wait for data to arrive at sk_receive_queue
2293 * @sk: sock to wait on
2294 * @timeo: for how long
2295 * @skb: last skb seen on sk_receive_queue
2296 *
2297 * Now socket state including sk->sk_err is changed only under lock,
2298 * hence we may omit checks after joining wait queue.
2299 * We check receive queue before schedule() only as optimization;
2300 * it is very likely that release_sock() added new data.
2301 */
sk_wait_data(struct sock * sk,long * timeo,const struct sk_buff * skb)2302 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2303 {
2304 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2305 int rc;
2306
2307 add_wait_queue(sk_sleep(sk), &wait);
2308 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2309 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2310 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2311 remove_wait_queue(sk_sleep(sk), &wait);
2312 return rc;
2313 }
2314 EXPORT_SYMBOL(sk_wait_data);
2315
2316 /**
2317 * __sk_mem_raise_allocated - increase memory_allocated
2318 * @sk: socket
2319 * @size: memory size to allocate
2320 * @amt: pages to allocate
2321 * @kind: allocation type
2322 *
2323 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2324 */
__sk_mem_raise_allocated(struct sock * sk,int size,int amt,int kind)2325 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2326 {
2327 struct proto *prot = sk->sk_prot;
2328 long allocated = sk_memory_allocated_add(sk, amt);
2329
2330 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2331 !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2332 goto suppress_allocation;
2333
2334 /* Under limit. */
2335 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2336 sk_leave_memory_pressure(sk);
2337 return 1;
2338 }
2339
2340 /* Under pressure. */
2341 if (allocated > sk_prot_mem_limits(sk, 1))
2342 sk_enter_memory_pressure(sk);
2343
2344 /* Over hard limit. */
2345 if (allocated > sk_prot_mem_limits(sk, 2))
2346 goto suppress_allocation;
2347
2348 /* guarantee minimum buffer size under pressure */
2349 if (kind == SK_MEM_RECV) {
2350 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2351 return 1;
2352
2353 } else { /* SK_MEM_SEND */
2354 if (sk->sk_type == SOCK_STREAM) {
2355 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2356 return 1;
2357 } else if (refcount_read(&sk->sk_wmem_alloc) <
2358 prot->sysctl_wmem[0])
2359 return 1;
2360 }
2361
2362 if (sk_has_memory_pressure(sk)) {
2363 u64 alloc;
2364
2365 if (!sk_under_memory_pressure(sk))
2366 return 1;
2367 alloc = sk_sockets_allocated_read_positive(sk);
2368 if (sk_prot_mem_limits(sk, 2) > alloc *
2369 sk_mem_pages(sk->sk_wmem_queued +
2370 atomic_read(&sk->sk_rmem_alloc) +
2371 sk->sk_forward_alloc))
2372 return 1;
2373 }
2374
2375 suppress_allocation:
2376
2377 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2378 sk_stream_moderate_sndbuf(sk);
2379
2380 /* Fail only if socket is _under_ its sndbuf.
2381 * In this case we cannot block, so that we have to fail.
2382 */
2383 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2384 return 1;
2385 }
2386
2387 trace_sock_exceed_buf_limit(sk, prot, allocated);
2388
2389 sk_memory_allocated_sub(sk, amt);
2390
2391 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2392 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2393
2394 return 0;
2395 }
2396 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2397
2398 /**
2399 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2400 * @sk: socket
2401 * @size: memory size to allocate
2402 * @kind: allocation type
2403 *
2404 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2405 * rmem allocation. This function assumes that protocols which have
2406 * memory_pressure use sk_wmem_queued as write buffer accounting.
2407 */
__sk_mem_schedule(struct sock * sk,int size,int kind)2408 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2409 {
2410 int ret, amt = sk_mem_pages(size);
2411
2412 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2413 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2414 if (!ret)
2415 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2416 return ret;
2417 }
2418 EXPORT_SYMBOL(__sk_mem_schedule);
2419
2420 /**
2421 * __sk_mem_reduce_allocated - reclaim memory_allocated
2422 * @sk: socket
2423 * @amount: number of quanta
2424 *
2425 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2426 */
__sk_mem_reduce_allocated(struct sock * sk,int amount)2427 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2428 {
2429 sk_memory_allocated_sub(sk, amount);
2430
2431 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2432 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2433
2434 if (sk_under_memory_pressure(sk) &&
2435 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2436 sk_leave_memory_pressure(sk);
2437 }
2438 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2439
2440 /**
2441 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2442 * @sk: socket
2443 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2444 */
__sk_mem_reclaim(struct sock * sk,int amount)2445 void __sk_mem_reclaim(struct sock *sk, int amount)
2446 {
2447 amount >>= SK_MEM_QUANTUM_SHIFT;
2448 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2449 __sk_mem_reduce_allocated(sk, amount);
2450 }
2451 EXPORT_SYMBOL(__sk_mem_reclaim);
2452
sk_set_peek_off(struct sock * sk,int val)2453 int sk_set_peek_off(struct sock *sk, int val)
2454 {
2455 sk->sk_peek_off = val;
2456 return 0;
2457 }
2458 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2459
2460 /*
2461 * Set of default routines for initialising struct proto_ops when
2462 * the protocol does not support a particular function. In certain
2463 * cases where it makes no sense for a protocol to have a "do nothing"
2464 * function, some default processing is provided.
2465 */
2466
sock_no_bind(struct socket * sock,struct sockaddr * saddr,int len)2467 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2468 {
2469 return -EOPNOTSUPP;
2470 }
2471 EXPORT_SYMBOL(sock_no_bind);
2472
sock_no_connect(struct socket * sock,struct sockaddr * saddr,int len,int flags)2473 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2474 int len, int flags)
2475 {
2476 return -EOPNOTSUPP;
2477 }
2478 EXPORT_SYMBOL(sock_no_connect);
2479
sock_no_socketpair(struct socket * sock1,struct socket * sock2)2480 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2481 {
2482 return -EOPNOTSUPP;
2483 }
2484 EXPORT_SYMBOL(sock_no_socketpair);
2485
sock_no_accept(struct socket * sock,struct socket * newsock,int flags,bool kern)2486 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2487 bool kern)
2488 {
2489 return -EOPNOTSUPP;
2490 }
2491 EXPORT_SYMBOL(sock_no_accept);
2492
sock_no_getname(struct socket * sock,struct sockaddr * saddr,int * len,int peer)2493 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2494 int *len, int peer)
2495 {
2496 return -EOPNOTSUPP;
2497 }
2498 EXPORT_SYMBOL(sock_no_getname);
2499
sock_no_poll(struct file * file,struct socket * sock,poll_table * pt)2500 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2501 {
2502 return 0;
2503 }
2504 EXPORT_SYMBOL(sock_no_poll);
2505
sock_no_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)2506 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2507 {
2508 return -EOPNOTSUPP;
2509 }
2510 EXPORT_SYMBOL(sock_no_ioctl);
2511
sock_no_listen(struct socket * sock,int backlog)2512 int sock_no_listen(struct socket *sock, int backlog)
2513 {
2514 return -EOPNOTSUPP;
2515 }
2516 EXPORT_SYMBOL(sock_no_listen);
2517
sock_no_shutdown(struct socket * sock,int how)2518 int sock_no_shutdown(struct socket *sock, int how)
2519 {
2520 return -EOPNOTSUPP;
2521 }
2522 EXPORT_SYMBOL(sock_no_shutdown);
2523
sock_no_setsockopt(struct socket * sock,int level,int optname,char __user * optval,unsigned int optlen)2524 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2525 char __user *optval, unsigned int optlen)
2526 {
2527 return -EOPNOTSUPP;
2528 }
2529 EXPORT_SYMBOL(sock_no_setsockopt);
2530
sock_no_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)2531 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2532 char __user *optval, int __user *optlen)
2533 {
2534 return -EOPNOTSUPP;
2535 }
2536 EXPORT_SYMBOL(sock_no_getsockopt);
2537
sock_no_sendmsg(struct socket * sock,struct msghdr * m,size_t len)2538 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2539 {
2540 return -EOPNOTSUPP;
2541 }
2542 EXPORT_SYMBOL(sock_no_sendmsg);
2543
sock_no_sendmsg_locked(struct sock * sk,struct msghdr * m,size_t len)2544 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2545 {
2546 return -EOPNOTSUPP;
2547 }
2548 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2549
sock_no_recvmsg(struct socket * sock,struct msghdr * m,size_t len,int flags)2550 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2551 int flags)
2552 {
2553 return -EOPNOTSUPP;
2554 }
2555 EXPORT_SYMBOL(sock_no_recvmsg);
2556
sock_no_mmap(struct file * file,struct socket * sock,struct vm_area_struct * vma)2557 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2558 {
2559 /* Mirror missing mmap method error code */
2560 return -ENODEV;
2561 }
2562 EXPORT_SYMBOL(sock_no_mmap);
2563
sock_no_sendpage(struct socket * sock,struct page * page,int offset,size_t size,int flags)2564 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2565 {
2566 ssize_t res;
2567 struct msghdr msg = {.msg_flags = flags};
2568 struct kvec iov;
2569 char *kaddr = kmap(page);
2570 iov.iov_base = kaddr + offset;
2571 iov.iov_len = size;
2572 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2573 kunmap(page);
2574 return res;
2575 }
2576 EXPORT_SYMBOL(sock_no_sendpage);
2577
sock_no_sendpage_locked(struct sock * sk,struct page * page,int offset,size_t size,int flags)2578 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2579 int offset, size_t size, int flags)
2580 {
2581 ssize_t res;
2582 struct msghdr msg = {.msg_flags = flags};
2583 struct kvec iov;
2584 char *kaddr = kmap(page);
2585
2586 iov.iov_base = kaddr + offset;
2587 iov.iov_len = size;
2588 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2589 kunmap(page);
2590 return res;
2591 }
2592 EXPORT_SYMBOL(sock_no_sendpage_locked);
2593
2594 /*
2595 * Default Socket Callbacks
2596 */
2597
sock_def_wakeup(struct sock * sk)2598 static void sock_def_wakeup(struct sock *sk)
2599 {
2600 struct socket_wq *wq;
2601
2602 rcu_read_lock();
2603 wq = rcu_dereference(sk->sk_wq);
2604 if (skwq_has_sleeper(wq))
2605 wake_up_interruptible_all(&wq->wait);
2606 rcu_read_unlock();
2607 }
2608
sock_def_error_report(struct sock * sk)2609 static void sock_def_error_report(struct sock *sk)
2610 {
2611 struct socket_wq *wq;
2612
2613 rcu_read_lock();
2614 wq = rcu_dereference(sk->sk_wq);
2615 if (skwq_has_sleeper(wq))
2616 wake_up_interruptible_poll(&wq->wait, POLLERR);
2617 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2618 rcu_read_unlock();
2619 }
2620
sock_def_readable(struct sock * sk)2621 static void sock_def_readable(struct sock *sk)
2622 {
2623 struct socket_wq *wq;
2624
2625 rcu_read_lock();
2626 wq = rcu_dereference(sk->sk_wq);
2627 if (skwq_has_sleeper(wq))
2628 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2629 POLLRDNORM | POLLRDBAND);
2630 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2631 rcu_read_unlock();
2632 }
2633
sock_def_write_space(struct sock * sk)2634 static void sock_def_write_space(struct sock *sk)
2635 {
2636 struct socket_wq *wq;
2637
2638 rcu_read_lock();
2639
2640 /* Do not wake up a writer until he can make "significant"
2641 * progress. --DaveM
2642 */
2643 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2644 wq = rcu_dereference(sk->sk_wq);
2645 if (skwq_has_sleeper(wq))
2646 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2647 POLLWRNORM | POLLWRBAND);
2648
2649 /* Should agree with poll, otherwise some programs break */
2650 if (sock_writeable(sk))
2651 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2652 }
2653
2654 rcu_read_unlock();
2655 }
2656
sock_def_destruct(struct sock * sk)2657 static void sock_def_destruct(struct sock *sk)
2658 {
2659 }
2660
sk_send_sigurg(struct sock * sk)2661 void sk_send_sigurg(struct sock *sk)
2662 {
2663 if (sk->sk_socket && sk->sk_socket->file)
2664 if (send_sigurg(&sk->sk_socket->file->f_owner))
2665 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2666 }
2667 EXPORT_SYMBOL(sk_send_sigurg);
2668
sk_reset_timer(struct sock * sk,struct timer_list * timer,unsigned long expires)2669 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2670 unsigned long expires)
2671 {
2672 if (!mod_timer(timer, expires))
2673 sock_hold(sk);
2674 }
2675 EXPORT_SYMBOL(sk_reset_timer);
2676
sk_stop_timer(struct sock * sk,struct timer_list * timer)2677 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2678 {
2679 if (del_timer(timer))
2680 __sock_put(sk);
2681 }
2682 EXPORT_SYMBOL(sk_stop_timer);
2683
sock_init_data(struct socket * sock,struct sock * sk)2684 void sock_init_data(struct socket *sock, struct sock *sk)
2685 {
2686 sk_init_common(sk);
2687 sk->sk_send_head = NULL;
2688
2689 init_timer(&sk->sk_timer);
2690
2691 sk->sk_allocation = GFP_KERNEL;
2692 sk->sk_rcvbuf = sysctl_rmem_default;
2693 sk->sk_sndbuf = sysctl_wmem_default;
2694 sk->sk_state = TCP_CLOSE;
2695 sk_set_socket(sk, sock);
2696
2697 sock_set_flag(sk, SOCK_ZAPPED);
2698
2699 if (sock) {
2700 sk->sk_type = sock->type;
2701 sk->sk_wq = sock->wq;
2702 sock->sk = sk;
2703 sk->sk_uid = SOCK_INODE(sock)->i_uid;
2704 } else {
2705 sk->sk_wq = NULL;
2706 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0);
2707 }
2708
2709 rwlock_init(&sk->sk_callback_lock);
2710 if (sk->sk_kern_sock)
2711 lockdep_set_class_and_name(
2712 &sk->sk_callback_lock,
2713 af_kern_callback_keys + sk->sk_family,
2714 af_family_kern_clock_key_strings[sk->sk_family]);
2715 else
2716 lockdep_set_class_and_name(
2717 &sk->sk_callback_lock,
2718 af_callback_keys + sk->sk_family,
2719 af_family_clock_key_strings[sk->sk_family]);
2720
2721 sk->sk_state_change = sock_def_wakeup;
2722 sk->sk_data_ready = sock_def_readable;
2723 sk->sk_write_space = sock_def_write_space;
2724 sk->sk_error_report = sock_def_error_report;
2725 sk->sk_destruct = sock_def_destruct;
2726
2727 sk->sk_frag.page = NULL;
2728 sk->sk_frag.offset = 0;
2729 sk->sk_peek_off = -1;
2730
2731 sk->sk_peer_pid = NULL;
2732 sk->sk_peer_cred = NULL;
2733 sk->sk_write_pending = 0;
2734 sk->sk_rcvlowat = 1;
2735 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2736 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2737
2738 sk->sk_stamp = SK_DEFAULT_STAMP;
2739 #if BITS_PER_LONG==32
2740 seqlock_init(&sk->sk_stamp_seq);
2741 #endif
2742 atomic_set(&sk->sk_zckey, 0);
2743
2744 #ifdef CONFIG_NET_RX_BUSY_POLL
2745 sk->sk_napi_id = 0;
2746 sk->sk_ll_usec = sysctl_net_busy_read;
2747 #endif
2748
2749 sk->sk_max_pacing_rate = ~0U;
2750 sk->sk_pacing_rate = ~0U;
2751 sk->sk_incoming_cpu = -1;
2752 /*
2753 * Before updating sk_refcnt, we must commit prior changes to memory
2754 * (Documentation/RCU/rculist_nulls.txt for details)
2755 */
2756 smp_wmb();
2757 refcount_set(&sk->sk_refcnt, 1);
2758 atomic_set(&sk->sk_drops, 0);
2759 }
2760 EXPORT_SYMBOL(sock_init_data);
2761
lock_sock_nested(struct sock * sk,int subclass)2762 void lock_sock_nested(struct sock *sk, int subclass)
2763 {
2764 might_sleep();
2765 spin_lock_bh(&sk->sk_lock.slock);
2766 if (sk->sk_lock.owned)
2767 __lock_sock(sk);
2768 sk->sk_lock.owned = 1;
2769 spin_unlock(&sk->sk_lock.slock);
2770 /*
2771 * The sk_lock has mutex_lock() semantics here:
2772 */
2773 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2774 local_bh_enable();
2775 }
2776 EXPORT_SYMBOL(lock_sock_nested);
2777
release_sock(struct sock * sk)2778 void release_sock(struct sock *sk)
2779 {
2780 spin_lock_bh(&sk->sk_lock.slock);
2781 if (sk->sk_backlog.tail)
2782 __release_sock(sk);
2783
2784 /* Warning : release_cb() might need to release sk ownership,
2785 * ie call sock_release_ownership(sk) before us.
2786 */
2787 if (sk->sk_prot->release_cb)
2788 sk->sk_prot->release_cb(sk);
2789
2790 sock_release_ownership(sk);
2791 if (waitqueue_active(&sk->sk_lock.wq))
2792 wake_up(&sk->sk_lock.wq);
2793 spin_unlock_bh(&sk->sk_lock.slock);
2794 }
2795 EXPORT_SYMBOL(release_sock);
2796
2797 /**
2798 * lock_sock_fast - fast version of lock_sock
2799 * @sk: socket
2800 *
2801 * This version should be used for very small section, where process wont block
2802 * return false if fast path is taken:
2803 *
2804 * sk_lock.slock locked, owned = 0, BH disabled
2805 *
2806 * return true if slow path is taken:
2807 *
2808 * sk_lock.slock unlocked, owned = 1, BH enabled
2809 */
lock_sock_fast(struct sock * sk)2810 bool lock_sock_fast(struct sock *sk)
2811 {
2812 might_sleep();
2813 spin_lock_bh(&sk->sk_lock.slock);
2814
2815 if (!sk->sk_lock.owned)
2816 /*
2817 * Note : We must disable BH
2818 */
2819 return false;
2820
2821 __lock_sock(sk);
2822 sk->sk_lock.owned = 1;
2823 spin_unlock(&sk->sk_lock.slock);
2824 /*
2825 * The sk_lock has mutex_lock() semantics here:
2826 */
2827 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2828 local_bh_enable();
2829 return true;
2830 }
2831 EXPORT_SYMBOL(lock_sock_fast);
2832
sock_get_timestamp(struct sock * sk,struct timeval __user * userstamp)2833 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2834 {
2835 struct timeval tv;
2836 if (!sock_flag(sk, SOCK_TIMESTAMP))
2837 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2838 tv = ktime_to_timeval(sk->sk_stamp);
2839 if (tv.tv_sec == -1)
2840 return -ENOENT;
2841 if (tv.tv_sec == 0) {
2842 sk->sk_stamp = ktime_get_real();
2843 tv = ktime_to_timeval(sk->sk_stamp);
2844 }
2845 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2846 }
2847 EXPORT_SYMBOL(sock_get_timestamp);
2848
sock_get_timestampns(struct sock * sk,struct timespec __user * userstamp)2849 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2850 {
2851 struct timespec ts;
2852 if (!sock_flag(sk, SOCK_TIMESTAMP))
2853 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2854 ts = ktime_to_timespec(sk->sk_stamp);
2855 if (ts.tv_sec == -1)
2856 return -ENOENT;
2857 if (ts.tv_sec == 0) {
2858 sk->sk_stamp = ktime_get_real();
2859 ts = ktime_to_timespec(sk->sk_stamp);
2860 }
2861 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2862 }
2863 EXPORT_SYMBOL(sock_get_timestampns);
2864
sock_enable_timestamp(struct sock * sk,int flag)2865 void sock_enable_timestamp(struct sock *sk, int flag)
2866 {
2867 if (!sock_flag(sk, flag)) {
2868 unsigned long previous_flags = sk->sk_flags;
2869
2870 sock_set_flag(sk, flag);
2871 /*
2872 * we just set one of the two flags which require net
2873 * time stamping, but time stamping might have been on
2874 * already because of the other one
2875 */
2876 if (sock_needs_netstamp(sk) &&
2877 !(previous_flags & SK_FLAGS_TIMESTAMP))
2878 net_enable_timestamp();
2879 }
2880 }
2881
sock_recv_errqueue(struct sock * sk,struct msghdr * msg,int len,int level,int type)2882 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2883 int level, int type)
2884 {
2885 struct sock_exterr_skb *serr;
2886 struct sk_buff *skb;
2887 int copied, err;
2888
2889 err = -EAGAIN;
2890 skb = sock_dequeue_err_skb(sk);
2891 if (skb == NULL)
2892 goto out;
2893
2894 copied = skb->len;
2895 if (copied > len) {
2896 msg->msg_flags |= MSG_TRUNC;
2897 copied = len;
2898 }
2899 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2900 if (err)
2901 goto out_free_skb;
2902
2903 sock_recv_timestamp(msg, sk, skb);
2904
2905 serr = SKB_EXT_ERR(skb);
2906 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2907
2908 msg->msg_flags |= MSG_ERRQUEUE;
2909 err = copied;
2910
2911 out_free_skb:
2912 kfree_skb(skb);
2913 out:
2914 return err;
2915 }
2916 EXPORT_SYMBOL(sock_recv_errqueue);
2917
2918 /*
2919 * Get a socket option on an socket.
2920 *
2921 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2922 * asynchronous errors should be reported by getsockopt. We assume
2923 * this means if you specify SO_ERROR (otherwise whats the point of it).
2924 */
sock_common_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)2925 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2926 char __user *optval, int __user *optlen)
2927 {
2928 struct sock *sk = sock->sk;
2929
2930 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2931 }
2932 EXPORT_SYMBOL(sock_common_getsockopt);
2933
2934 #ifdef CONFIG_COMPAT
compat_sock_common_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)2935 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2936 char __user *optval, int __user *optlen)
2937 {
2938 struct sock *sk = sock->sk;
2939
2940 if (sk->sk_prot->compat_getsockopt != NULL)
2941 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2942 optval, optlen);
2943 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2944 }
2945 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2946 #endif
2947
sock_common_recvmsg(struct socket * sock,struct msghdr * msg,size_t size,int flags)2948 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2949 int flags)
2950 {
2951 struct sock *sk = sock->sk;
2952 int addr_len = 0;
2953 int err;
2954
2955 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2956 flags & ~MSG_DONTWAIT, &addr_len);
2957 if (err >= 0)
2958 msg->msg_namelen = addr_len;
2959 return err;
2960 }
2961 EXPORT_SYMBOL(sock_common_recvmsg);
2962
2963 /*
2964 * Set socket options on an inet socket.
2965 */
sock_common_setsockopt(struct socket * sock,int level,int optname,char __user * optval,unsigned int optlen)2966 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2967 char __user *optval, unsigned int optlen)
2968 {
2969 struct sock *sk = sock->sk;
2970
2971 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2972 }
2973 EXPORT_SYMBOL(sock_common_setsockopt);
2974
2975 #ifdef CONFIG_COMPAT
compat_sock_common_setsockopt(struct socket * sock,int level,int optname,char __user * optval,unsigned int optlen)2976 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2977 char __user *optval, unsigned int optlen)
2978 {
2979 struct sock *sk = sock->sk;
2980
2981 if (sk->sk_prot->compat_setsockopt != NULL)
2982 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2983 optval, optlen);
2984 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2985 }
2986 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2987 #endif
2988
sk_common_release(struct sock * sk)2989 void sk_common_release(struct sock *sk)
2990 {
2991 if (sk->sk_prot->destroy)
2992 sk->sk_prot->destroy(sk);
2993
2994 /*
2995 * Observation: when sock_common_release is called, processes have
2996 * no access to socket. But net still has.
2997 * Step one, detach it from networking:
2998 *
2999 * A. Remove from hash tables.
3000 */
3001
3002 sk->sk_prot->unhash(sk);
3003
3004 /*
3005 * In this point socket cannot receive new packets, but it is possible
3006 * that some packets are in flight because some CPU runs receiver and
3007 * did hash table lookup before we unhashed socket. They will achieve
3008 * receive queue and will be purged by socket destructor.
3009 *
3010 * Also we still have packets pending on receive queue and probably,
3011 * our own packets waiting in device queues. sock_destroy will drain
3012 * receive queue, but transmitted packets will delay socket destruction
3013 * until the last reference will be released.
3014 */
3015
3016 sock_orphan(sk);
3017
3018 xfrm_sk_free_policy(sk);
3019
3020 sk_refcnt_debug_release(sk);
3021
3022 sock_put(sk);
3023 }
3024 EXPORT_SYMBOL(sk_common_release);
3025
sk_get_meminfo(const struct sock * sk,u32 * mem)3026 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3027 {
3028 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3029
3030 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3031 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3032 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3033 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3034 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3035 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3036 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3037 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3038 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3039 }
3040
3041 #ifdef CONFIG_PROC_FS
3042 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
3043 struct prot_inuse {
3044 int val[PROTO_INUSE_NR];
3045 };
3046
3047 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3048
3049 #ifdef CONFIG_NET_NS
sock_prot_inuse_add(struct net * net,struct proto * prot,int val)3050 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3051 {
3052 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
3053 }
3054 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3055
sock_prot_inuse_get(struct net * net,struct proto * prot)3056 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3057 {
3058 int cpu, idx = prot->inuse_idx;
3059 int res = 0;
3060
3061 for_each_possible_cpu(cpu)
3062 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
3063
3064 return res >= 0 ? res : 0;
3065 }
3066 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3067
sock_inuse_init_net(struct net * net)3068 static int __net_init sock_inuse_init_net(struct net *net)
3069 {
3070 net->core.inuse = alloc_percpu(struct prot_inuse);
3071 return net->core.inuse ? 0 : -ENOMEM;
3072 }
3073
sock_inuse_exit_net(struct net * net)3074 static void __net_exit sock_inuse_exit_net(struct net *net)
3075 {
3076 free_percpu(net->core.inuse);
3077 }
3078
3079 static struct pernet_operations net_inuse_ops = {
3080 .init = sock_inuse_init_net,
3081 .exit = sock_inuse_exit_net,
3082 };
3083
net_inuse_init(void)3084 static __init int net_inuse_init(void)
3085 {
3086 if (register_pernet_subsys(&net_inuse_ops))
3087 panic("Cannot initialize net inuse counters");
3088
3089 return 0;
3090 }
3091
3092 core_initcall(net_inuse_init);
3093 #else
3094 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
3095
sock_prot_inuse_add(struct net * net,struct proto * prot,int val)3096 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3097 {
3098 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
3099 }
3100 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3101
sock_prot_inuse_get(struct net * net,struct proto * prot)3102 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3103 {
3104 int cpu, idx = prot->inuse_idx;
3105 int res = 0;
3106
3107 for_each_possible_cpu(cpu)
3108 res += per_cpu(prot_inuse, cpu).val[idx];
3109
3110 return res >= 0 ? res : 0;
3111 }
3112 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3113 #endif
3114
assign_proto_idx(struct proto * prot)3115 static void assign_proto_idx(struct proto *prot)
3116 {
3117 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3118
3119 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3120 pr_err("PROTO_INUSE_NR exhausted\n");
3121 return;
3122 }
3123
3124 set_bit(prot->inuse_idx, proto_inuse_idx);
3125 }
3126
release_proto_idx(struct proto * prot)3127 static void release_proto_idx(struct proto *prot)
3128 {
3129 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3130 clear_bit(prot->inuse_idx, proto_inuse_idx);
3131 }
3132 #else
assign_proto_idx(struct proto * prot)3133 static inline void assign_proto_idx(struct proto *prot)
3134 {
3135 }
3136
release_proto_idx(struct proto * prot)3137 static inline void release_proto_idx(struct proto *prot)
3138 {
3139 }
3140 #endif
3141
req_prot_cleanup(struct request_sock_ops * rsk_prot)3142 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3143 {
3144 if (!rsk_prot)
3145 return;
3146 kfree(rsk_prot->slab_name);
3147 rsk_prot->slab_name = NULL;
3148 kmem_cache_destroy(rsk_prot->slab);
3149 rsk_prot->slab = NULL;
3150 }
3151
req_prot_init(const struct proto * prot)3152 static int req_prot_init(const struct proto *prot)
3153 {
3154 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3155
3156 if (!rsk_prot)
3157 return 0;
3158
3159 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3160 prot->name);
3161 if (!rsk_prot->slab_name)
3162 return -ENOMEM;
3163
3164 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3165 rsk_prot->obj_size, 0,
3166 prot->slab_flags, NULL);
3167
3168 if (!rsk_prot->slab) {
3169 pr_crit("%s: Can't create request sock SLAB cache!\n",
3170 prot->name);
3171 return -ENOMEM;
3172 }
3173 return 0;
3174 }
3175
proto_register(struct proto * prot,int alloc_slab)3176 int proto_register(struct proto *prot, int alloc_slab)
3177 {
3178 if (alloc_slab) {
3179 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
3180 SLAB_HWCACHE_ALIGN | prot->slab_flags,
3181 NULL);
3182
3183 if (prot->slab == NULL) {
3184 pr_crit("%s: Can't create sock SLAB cache!\n",
3185 prot->name);
3186 goto out;
3187 }
3188
3189 if (req_prot_init(prot))
3190 goto out_free_request_sock_slab;
3191
3192 if (prot->twsk_prot != NULL) {
3193 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3194
3195 if (prot->twsk_prot->twsk_slab_name == NULL)
3196 goto out_free_request_sock_slab;
3197
3198 prot->twsk_prot->twsk_slab =
3199 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3200 prot->twsk_prot->twsk_obj_size,
3201 0,
3202 prot->slab_flags,
3203 NULL);
3204 if (prot->twsk_prot->twsk_slab == NULL)
3205 goto out_free_timewait_sock_slab_name;
3206 }
3207 }
3208
3209 mutex_lock(&proto_list_mutex);
3210 list_add(&prot->node, &proto_list);
3211 assign_proto_idx(prot);
3212 mutex_unlock(&proto_list_mutex);
3213 return 0;
3214
3215 out_free_timewait_sock_slab_name:
3216 kfree(prot->twsk_prot->twsk_slab_name);
3217 out_free_request_sock_slab:
3218 req_prot_cleanup(prot->rsk_prot);
3219
3220 kmem_cache_destroy(prot->slab);
3221 prot->slab = NULL;
3222 out:
3223 return -ENOBUFS;
3224 }
3225 EXPORT_SYMBOL(proto_register);
3226
proto_unregister(struct proto * prot)3227 void proto_unregister(struct proto *prot)
3228 {
3229 mutex_lock(&proto_list_mutex);
3230 release_proto_idx(prot);
3231 list_del(&prot->node);
3232 mutex_unlock(&proto_list_mutex);
3233
3234 kmem_cache_destroy(prot->slab);
3235 prot->slab = NULL;
3236
3237 req_prot_cleanup(prot->rsk_prot);
3238
3239 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3240 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3241 kfree(prot->twsk_prot->twsk_slab_name);
3242 prot->twsk_prot->twsk_slab = NULL;
3243 }
3244 }
3245 EXPORT_SYMBOL(proto_unregister);
3246
3247 #ifdef CONFIG_PROC_FS
proto_seq_start(struct seq_file * seq,loff_t * pos)3248 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3249 __acquires(proto_list_mutex)
3250 {
3251 mutex_lock(&proto_list_mutex);
3252 return seq_list_start_head(&proto_list, *pos);
3253 }
3254
proto_seq_next(struct seq_file * seq,void * v,loff_t * pos)3255 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3256 {
3257 return seq_list_next(v, &proto_list, pos);
3258 }
3259
proto_seq_stop(struct seq_file * seq,void * v)3260 static void proto_seq_stop(struct seq_file *seq, void *v)
3261 __releases(proto_list_mutex)
3262 {
3263 mutex_unlock(&proto_list_mutex);
3264 }
3265
proto_method_implemented(const void * method)3266 static char proto_method_implemented(const void *method)
3267 {
3268 return method == NULL ? 'n' : 'y';
3269 }
sock_prot_memory_allocated(struct proto * proto)3270 static long sock_prot_memory_allocated(struct proto *proto)
3271 {
3272 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3273 }
3274
sock_prot_memory_pressure(struct proto * proto)3275 static char *sock_prot_memory_pressure(struct proto *proto)
3276 {
3277 return proto->memory_pressure != NULL ?
3278 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3279 }
3280
proto_seq_printf(struct seq_file * seq,struct proto * proto)3281 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3282 {
3283
3284 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
3285 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3286 proto->name,
3287 proto->obj_size,
3288 sock_prot_inuse_get(seq_file_net(seq), proto),
3289 sock_prot_memory_allocated(proto),
3290 sock_prot_memory_pressure(proto),
3291 proto->max_header,
3292 proto->slab == NULL ? "no" : "yes",
3293 module_name(proto->owner),
3294 proto_method_implemented(proto->close),
3295 proto_method_implemented(proto->connect),
3296 proto_method_implemented(proto->disconnect),
3297 proto_method_implemented(proto->accept),
3298 proto_method_implemented(proto->ioctl),
3299 proto_method_implemented(proto->init),
3300 proto_method_implemented(proto->destroy),
3301 proto_method_implemented(proto->shutdown),
3302 proto_method_implemented(proto->setsockopt),
3303 proto_method_implemented(proto->getsockopt),
3304 proto_method_implemented(proto->sendmsg),
3305 proto_method_implemented(proto->recvmsg),
3306 proto_method_implemented(proto->sendpage),
3307 proto_method_implemented(proto->bind),
3308 proto_method_implemented(proto->backlog_rcv),
3309 proto_method_implemented(proto->hash),
3310 proto_method_implemented(proto->unhash),
3311 proto_method_implemented(proto->get_port),
3312 proto_method_implemented(proto->enter_memory_pressure));
3313 }
3314
proto_seq_show(struct seq_file * seq,void * v)3315 static int proto_seq_show(struct seq_file *seq, void *v)
3316 {
3317 if (v == &proto_list)
3318 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3319 "protocol",
3320 "size",
3321 "sockets",
3322 "memory",
3323 "press",
3324 "maxhdr",
3325 "slab",
3326 "module",
3327 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3328 else
3329 proto_seq_printf(seq, list_entry(v, struct proto, node));
3330 return 0;
3331 }
3332
3333 static const struct seq_operations proto_seq_ops = {
3334 .start = proto_seq_start,
3335 .next = proto_seq_next,
3336 .stop = proto_seq_stop,
3337 .show = proto_seq_show,
3338 };
3339
proto_seq_open(struct inode * inode,struct file * file)3340 static int proto_seq_open(struct inode *inode, struct file *file)
3341 {
3342 return seq_open_net(inode, file, &proto_seq_ops,
3343 sizeof(struct seq_net_private));
3344 }
3345
3346 static const struct file_operations proto_seq_fops = {
3347 .owner = THIS_MODULE,
3348 .open = proto_seq_open,
3349 .read = seq_read,
3350 .llseek = seq_lseek,
3351 .release = seq_release_net,
3352 };
3353
proto_init_net(struct net * net)3354 static __net_init int proto_init_net(struct net *net)
3355 {
3356 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3357 return -ENOMEM;
3358
3359 return 0;
3360 }
3361
proto_exit_net(struct net * net)3362 static __net_exit void proto_exit_net(struct net *net)
3363 {
3364 remove_proc_entry("protocols", net->proc_net);
3365 }
3366
3367
3368 static __net_initdata struct pernet_operations proto_net_ops = {
3369 .init = proto_init_net,
3370 .exit = proto_exit_net,
3371 };
3372
proto_init(void)3373 static int __init proto_init(void)
3374 {
3375 return register_pernet_subsys(&proto_net_ops);
3376 }
3377
3378 subsys_initcall(proto_init);
3379
3380 #endif /* PROC_FS */
3381
3382 #ifdef CONFIG_NET_RX_BUSY_POLL
sk_busy_loop_end(void * p,unsigned long start_time)3383 bool sk_busy_loop_end(void *p, unsigned long start_time)
3384 {
3385 struct sock *sk = p;
3386
3387 return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
3388 sk_busy_loop_timeout(sk, start_time);
3389 }
3390 EXPORT_SYMBOL(sk_busy_loop_end);
3391 #endif /* CONFIG_NET_RX_BUSY_POLL */
3392