1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Generic socket support routines. Memory allocators, socket lock/release
8 * handler for protocols to use and generic option handler.
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87
88 #include <linux/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/udp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 #include <linux/static_key.h>
115 #include <linux/memcontrol.h>
116 #include <linux/prefetch.h>
117 #include <linux/compat.h>
118 #include <linux/mroute.h>
119 #include <linux/mroute6.h>
120 #include <linux/icmpv6.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 <linux/skbuff_ref.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <net/proto_memory.h>
132 #include <linux/net_tstamp.h>
133 #include <net/xfrm.h>
134 #include <linux/ipsec.h>
135 #include <net/cls_cgroup.h>
136 #include <net/netprio_cgroup.h>
137 #include <linux/sock_diag.h>
138
139 #include <linux/filter.h>
140 #include <net/sock_reuseport.h>
141 #include <net/bpf_sk_storage.h>
142
143 #include <trace/events/sock.h>
144
145 #include <net/tcp.h>
146 #include <net/busy_poll.h>
147 #include <net/phonet/phonet.h>
148
149 #include <linux/ethtool.h>
150
151 #include <uapi/linux/pidfd.h>
152
153 #include "dev.h"
154
155 static DEFINE_MUTEX(proto_list_mutex);
156 static LIST_HEAD(proto_list);
157
158 static void sock_def_write_space_wfree(struct sock *sk);
159 static void sock_def_write_space(struct sock *sk);
160
161 /**
162 * sk_ns_capable - General socket capability test
163 * @sk: Socket to use a capability on or through
164 * @user_ns: The user namespace of the capability to use
165 * @cap: The capability to use
166 *
167 * Test to see if the opener of the socket had when the socket was
168 * created and the current process has the capability @cap in the user
169 * namespace @user_ns.
170 */
sk_ns_capable(const struct sock * sk,struct user_namespace * user_ns,int cap)171 bool sk_ns_capable(const struct sock *sk,
172 struct user_namespace *user_ns, int cap)
173 {
174 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
175 ns_capable(user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_ns_capable);
178
179 /**
180 * sk_capable - Socket global capability test
181 * @sk: Socket to use a capability on or through
182 * @cap: The global capability to use
183 *
184 * Test to see if the opener of the socket had when the socket was
185 * created and the current process has the capability @cap in all user
186 * namespaces.
187 */
sk_capable(const struct sock * sk,int cap)188 bool sk_capable(const struct sock *sk, int cap)
189 {
190 return sk_ns_capable(sk, &init_user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_capable);
193
194 /**
195 * sk_net_capable - Network namespace socket capability test
196 * @sk: Socket to use a capability on or through
197 * @cap: The capability to use
198 *
199 * Test to see if the opener of the socket had when the socket was created
200 * and the current process has the capability @cap over the network namespace
201 * the socket is a member of.
202 */
sk_net_capable(const struct sock * sk,int cap)203 bool sk_net_capable(const struct sock *sk, int cap)
204 {
205 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
206 }
207 EXPORT_SYMBOL(sk_net_capable);
208
209 /*
210 * Each address family might have different locking rules, so we have
211 * one slock key per address family and separate keys for internal and
212 * userspace sockets.
213 */
214 static struct lock_class_key af_family_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_keys[AF_MAX];
216 static struct lock_class_key af_family_slock_keys[AF_MAX];
217 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
218
219 /*
220 * Make lock validator output more readable. (we pre-construct these
221 * strings build-time, so that runtime initialization of socket
222 * locks is fast):
223 */
224
225 #define _sock_locks(x) \
226 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
227 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
228 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
229 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
230 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
231 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
232 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
233 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
234 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
235 x "27" , x "28" , x "AF_CAN" , \
236 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
237 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
238 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
239 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
240 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
241 x "AF_MCTP" , \
242 x "AF_MAX"
243
244 static const char *const af_family_key_strings[AF_MAX+1] = {
245 _sock_locks("sk_lock-")
246 };
247 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
248 _sock_locks("slock-")
249 };
250 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
251 _sock_locks("clock-")
252 };
253
254 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
255 _sock_locks("k-sk_lock-")
256 };
257 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
258 _sock_locks("k-slock-")
259 };
260 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
261 _sock_locks("k-clock-")
262 };
263 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
264 _sock_locks("rlock-")
265 };
266 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
267 _sock_locks("wlock-")
268 };
269 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
270 _sock_locks("elock-")
271 };
272
273 /*
274 * sk_callback_lock and sk queues locking rules are per-address-family,
275 * so split the lock classes by using a per-AF key:
276 */
277 static struct lock_class_key af_callback_keys[AF_MAX];
278 static struct lock_class_key af_rlock_keys[AF_MAX];
279 static struct lock_class_key af_wlock_keys[AF_MAX];
280 static struct lock_class_key af_elock_keys[AF_MAX];
281 static struct lock_class_key af_kern_callback_keys[AF_MAX];
282
283 /* Run time adjustable parameters. */
284 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
290
291 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
292 EXPORT_SYMBOL_GPL(memalloc_socks_key);
293
294 /**
295 * sk_set_memalloc - sets %SOCK_MEMALLOC
296 * @sk: socket to set it on
297 *
298 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
299 * It's the responsibility of the admin to adjust min_free_kbytes
300 * to meet the requirements
301 */
sk_set_memalloc(struct sock * sk)302 void sk_set_memalloc(struct sock *sk)
303 {
304 sock_set_flag(sk, SOCK_MEMALLOC);
305 sk->sk_allocation |= __GFP_MEMALLOC;
306 static_branch_inc(&memalloc_socks_key);
307 }
308 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309
sk_clear_memalloc(struct sock * sk)310 void sk_clear_memalloc(struct sock *sk)
311 {
312 sock_reset_flag(sk, SOCK_MEMALLOC);
313 sk->sk_allocation &= ~__GFP_MEMALLOC;
314 static_branch_dec(&memalloc_socks_key);
315
316 /*
317 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
318 * progress of swapping. SOCK_MEMALLOC may be cleared while
319 * it has rmem allocations due to the last swapfile being deactivated
320 * but there is a risk that the socket is unusable due to exceeding
321 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 */
323 sk_mem_reclaim(sk);
324 }
325 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326
__sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)327 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
328 {
329 int ret;
330 unsigned int noreclaim_flag;
331
332 /* these should have been dropped before queueing */
333 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334
335 noreclaim_flag = memalloc_noreclaim_save();
336 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 tcp_v6_do_rcv,
338 tcp_v4_do_rcv,
339 sk, skb);
340 memalloc_noreclaim_restore(noreclaim_flag);
341
342 return ret;
343 }
344 EXPORT_SYMBOL(__sk_backlog_rcv);
345
sk_error_report(struct sock * sk)346 void sk_error_report(struct sock *sk)
347 {
348 sk->sk_error_report(sk);
349
350 switch (sk->sk_family) {
351 case AF_INET:
352 fallthrough;
353 case AF_INET6:
354 trace_inet_sk_error_report(sk);
355 break;
356 default:
357 break;
358 }
359 }
360 EXPORT_SYMBOL(sk_error_report);
361
sock_get_timeout(long timeo,void * optval,bool old_timeval)362 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 {
364 struct __kernel_sock_timeval tv;
365
366 if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 tv.tv_sec = 0;
368 tv.tv_usec = 0;
369 } else {
370 tv.tv_sec = timeo / HZ;
371 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
372 }
373
374 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
375 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
376 *(struct old_timeval32 *)optval = tv32;
377 return sizeof(tv32);
378 }
379
380 if (old_timeval) {
381 struct __kernel_old_timeval old_tv;
382 old_tv.tv_sec = tv.tv_sec;
383 old_tv.tv_usec = tv.tv_usec;
384 *(struct __kernel_old_timeval *)optval = old_tv;
385 return sizeof(old_tv);
386 }
387
388 *(struct __kernel_sock_timeval *)optval = tv;
389 return sizeof(tv);
390 }
391 EXPORT_SYMBOL(sock_get_timeout);
392
sock_copy_user_timeval(struct __kernel_sock_timeval * tv,sockptr_t optval,int optlen,bool old_timeval)393 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
394 sockptr_t optval, int optlen, bool old_timeval)
395 {
396 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
397 struct old_timeval32 tv32;
398
399 if (optlen < sizeof(tv32))
400 return -EINVAL;
401
402 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 return -EFAULT;
404 tv->tv_sec = tv32.tv_sec;
405 tv->tv_usec = tv32.tv_usec;
406 } else if (old_timeval) {
407 struct __kernel_old_timeval old_tv;
408
409 if (optlen < sizeof(old_tv))
410 return -EINVAL;
411 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 return -EFAULT;
413 tv->tv_sec = old_tv.tv_sec;
414 tv->tv_usec = old_tv.tv_usec;
415 } else {
416 if (optlen < sizeof(*tv))
417 return -EINVAL;
418 if (copy_from_sockptr(tv, optval, sizeof(*tv)))
419 return -EFAULT;
420 }
421
422 return 0;
423 }
424 EXPORT_SYMBOL(sock_copy_user_timeval);
425
sock_set_timeout(long * timeo_p,sockptr_t optval,int optlen,bool old_timeval)426 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
427 bool old_timeval)
428 {
429 struct __kernel_sock_timeval tv;
430 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
431 long val;
432
433 if (err)
434 return err;
435
436 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
437 return -EDOM;
438
439 if (tv.tv_sec < 0) {
440 static int warned __read_mostly;
441
442 WRITE_ONCE(*timeo_p, 0);
443 if (warned < 10 && net_ratelimit()) {
444 warned++;
445 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
446 __func__, current->comm, task_pid_nr(current));
447 }
448 return 0;
449 }
450 val = MAX_SCHEDULE_TIMEOUT;
451 if ((tv.tv_sec || tv.tv_usec) &&
452 (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
453 val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 USEC_PER_SEC / HZ);
455 WRITE_ONCE(*timeo_p, val);
456 return 0;
457 }
458
sk_set_prio_allowed(const struct sock * sk,int val)459 static bool sk_set_prio_allowed(const struct sock *sk, int val)
460 {
461 return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
462 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
463 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
464 }
465
sock_needs_netstamp(const struct sock * sk)466 static bool sock_needs_netstamp(const struct sock *sk)
467 {
468 switch (sk->sk_family) {
469 case AF_UNSPEC:
470 case AF_UNIX:
471 return false;
472 default:
473 return true;
474 }
475 }
476
sock_disable_timestamp(struct sock * sk,unsigned long flags)477 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
478 {
479 if (sk->sk_flags & flags) {
480 sk->sk_flags &= ~flags;
481 if (sock_needs_netstamp(sk) &&
482 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
483 net_disable_timestamp();
484 }
485 }
486
487
__sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
489 {
490 unsigned long flags;
491 struct sk_buff_head *list = &sk->sk_receive_queue;
492
493 if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
494 atomic_inc(&sk->sk_drops);
495 trace_sock_rcvqueue_full(sk, skb);
496 return -ENOMEM;
497 }
498
499 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 atomic_inc(&sk->sk_drops);
501 return -ENOBUFS;
502 }
503
504 skb->dev = NULL;
505 skb_set_owner_r(skb, sk);
506
507 /* we escape from rcu protected region, make sure we dont leak
508 * a norefcounted dst
509 */
510 skb_dst_force(skb);
511
512 spin_lock_irqsave(&list->lock, flags);
513 sock_skb_set_dropcount(sk, skb);
514 __skb_queue_tail(list, skb);
515 spin_unlock_irqrestore(&list->lock, flags);
516
517 if (!sock_flag(sk, SOCK_DEAD))
518 sk->sk_data_ready(sk);
519 return 0;
520 }
521 EXPORT_SYMBOL(__sock_queue_rcv_skb);
522
sock_queue_rcv_skb_reason(struct sock * sk,struct sk_buff * skb,enum skb_drop_reason * reason)523 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
524 enum skb_drop_reason *reason)
525 {
526 enum skb_drop_reason drop_reason;
527 int err;
528
529 err = sk_filter_reason(sk, skb, &drop_reason);
530 if (err)
531 goto out;
532
533 err = __sock_queue_rcv_skb(sk, skb);
534 switch (err) {
535 case -ENOMEM:
536 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
537 break;
538 case -ENOBUFS:
539 drop_reason = SKB_DROP_REASON_PROTO_MEM;
540 break;
541 default:
542 drop_reason = SKB_NOT_DROPPED_YET;
543 break;
544 }
545 out:
546 if (reason)
547 *reason = drop_reason;
548 return err;
549 }
550 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
551
__sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested,unsigned int trim_cap,bool refcounted)552 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
553 const int nested, unsigned int trim_cap, bool refcounted)
554 {
555 enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
556 int rc = NET_RX_SUCCESS;
557 int err;
558
559 if (sk_filter_trim_cap(sk, skb, trim_cap, &reason))
560 goto discard_and_relse;
561
562 skb->dev = NULL;
563
564 if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
565 atomic_inc(&sk->sk_drops);
566 reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
567 goto discard_and_relse;
568 }
569 if (nested)
570 bh_lock_sock_nested(sk);
571 else
572 bh_lock_sock(sk);
573 if (!sock_owned_by_user(sk)) {
574 /*
575 * trylock + unlock semantics:
576 */
577 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
578
579 rc = sk_backlog_rcv(sk, skb);
580
581 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
582 } else if ((err = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))) {
583 bh_unlock_sock(sk);
584 if (err == -ENOMEM)
585 reason = SKB_DROP_REASON_PFMEMALLOC;
586 if (err == -ENOBUFS)
587 reason = SKB_DROP_REASON_SOCKET_BACKLOG;
588 atomic_inc(&sk->sk_drops);
589 goto discard_and_relse;
590 }
591
592 bh_unlock_sock(sk);
593 out:
594 if (refcounted)
595 sock_put(sk);
596 return rc;
597 discard_and_relse:
598 sk_skb_reason_drop(sk, skb, reason);
599 goto out;
600 }
601 EXPORT_SYMBOL(__sk_receive_skb);
602
603 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
604 u32));
605 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
606 u32));
__sk_dst_check(struct sock * sk,u32 cookie)607 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 struct dst_entry *dst = __sk_dst_get(sk);
610
611 if (dst && READ_ONCE(dst->obsolete) &&
612 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 dst, cookie) == NULL) {
614 sk_tx_queue_clear(sk);
615 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
616 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
617 dst_release(dst);
618 return NULL;
619 }
620
621 return dst;
622 }
623 EXPORT_SYMBOL(__sk_dst_check);
624
sk_dst_check(struct sock * sk,u32 cookie)625 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
626 {
627 struct dst_entry *dst = sk_dst_get(sk);
628
629 if (dst && READ_ONCE(dst->obsolete) &&
630 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
631 dst, cookie) == NULL) {
632 sk_dst_reset(sk);
633 dst_release(dst);
634 return NULL;
635 }
636
637 return dst;
638 }
639 EXPORT_SYMBOL(sk_dst_check);
640
sock_bindtoindex_locked(struct sock * sk,int ifindex)641 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
642 {
643 int ret = -ENOPROTOOPT;
644 #ifdef CONFIG_NETDEVICES
645 struct net *net = sock_net(sk);
646
647 /* Sorry... */
648 ret = -EPERM;
649 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
650 goto out;
651
652 ret = -EINVAL;
653 if (ifindex < 0)
654 goto out;
655
656 /* Paired with all READ_ONCE() done locklessly. */
657 WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
658
659 if (sk->sk_prot->rehash)
660 sk->sk_prot->rehash(sk);
661 sk_dst_reset(sk);
662
663 ret = 0;
664
665 out:
666 #endif
667
668 return ret;
669 }
670
sock_bindtoindex(struct sock * sk,int ifindex,bool lock_sk)671 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
672 {
673 int ret;
674
675 if (lock_sk)
676 lock_sock(sk);
677 ret = sock_bindtoindex_locked(sk, ifindex);
678 if (lock_sk)
679 release_sock(sk);
680
681 return ret;
682 }
683 EXPORT_SYMBOL(sock_bindtoindex);
684
sock_setbindtodevice(struct sock * sk,sockptr_t optval,int optlen)685 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
686 {
687 int ret = -ENOPROTOOPT;
688 #ifdef CONFIG_NETDEVICES
689 struct net *net = sock_net(sk);
690 char devname[IFNAMSIZ];
691 int index;
692
693 ret = -EINVAL;
694 if (optlen < 0)
695 goto out;
696
697 /* Bind this socket to a particular device like "eth0",
698 * as specified in the passed interface name. If the
699 * name is "" or the option length is zero the socket
700 * is not bound.
701 */
702 if (optlen > IFNAMSIZ - 1)
703 optlen = IFNAMSIZ - 1;
704 memset(devname, 0, sizeof(devname));
705
706 ret = -EFAULT;
707 if (copy_from_sockptr(devname, optval, optlen))
708 goto out;
709
710 index = 0;
711 if (devname[0] != '\0') {
712 struct net_device *dev;
713
714 rcu_read_lock();
715 dev = dev_get_by_name_rcu(net, devname);
716 if (dev)
717 index = dev->ifindex;
718 rcu_read_unlock();
719 ret = -ENODEV;
720 if (!dev)
721 goto out;
722 }
723
724 sockopt_lock_sock(sk);
725 ret = sock_bindtoindex_locked(sk, index);
726 sockopt_release_sock(sk);
727 out:
728 #endif
729
730 return ret;
731 }
732
sock_getbindtodevice(struct sock * sk,sockptr_t optval,sockptr_t optlen,int len)733 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
734 sockptr_t optlen, int len)
735 {
736 int ret = -ENOPROTOOPT;
737 #ifdef CONFIG_NETDEVICES
738 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
739 struct net *net = sock_net(sk);
740 char devname[IFNAMSIZ];
741
742 if (bound_dev_if == 0) {
743 len = 0;
744 goto zero;
745 }
746
747 ret = -EINVAL;
748 if (len < IFNAMSIZ)
749 goto out;
750
751 ret = netdev_get_name(net, devname, bound_dev_if);
752 if (ret)
753 goto out;
754
755 len = strlen(devname) + 1;
756
757 ret = -EFAULT;
758 if (copy_to_sockptr(optval, devname, len))
759 goto out;
760
761 zero:
762 ret = -EFAULT;
763 if (copy_to_sockptr(optlen, &len, sizeof(int)))
764 goto out;
765
766 ret = 0;
767
768 out:
769 #endif
770
771 return ret;
772 }
773
sk_mc_loop(const struct sock * sk)774 bool sk_mc_loop(const struct sock *sk)
775 {
776 if (dev_recursion_level())
777 return false;
778 if (!sk)
779 return true;
780 /* IPV6_ADDRFORM can change sk->sk_family under us. */
781 switch (READ_ONCE(sk->sk_family)) {
782 case AF_INET:
783 return inet_test_bit(MC_LOOP, sk);
784 #if IS_ENABLED(CONFIG_IPV6)
785 case AF_INET6:
786 return inet6_test_bit(MC6_LOOP, sk);
787 #endif
788 }
789 WARN_ON_ONCE(1);
790 return true;
791 }
792 EXPORT_SYMBOL(sk_mc_loop);
793
sock_set_reuseaddr(struct sock * sk)794 void sock_set_reuseaddr(struct sock *sk)
795 {
796 lock_sock(sk);
797 sk->sk_reuse = SK_CAN_REUSE;
798 release_sock(sk);
799 }
800 EXPORT_SYMBOL(sock_set_reuseaddr);
801
sock_set_reuseport(struct sock * sk)802 void sock_set_reuseport(struct sock *sk)
803 {
804 lock_sock(sk);
805 sk->sk_reuseport = true;
806 release_sock(sk);
807 }
808 EXPORT_SYMBOL(sock_set_reuseport);
809
sock_no_linger(struct sock * sk)810 void sock_no_linger(struct sock *sk)
811 {
812 lock_sock(sk);
813 WRITE_ONCE(sk->sk_lingertime, 0);
814 sock_set_flag(sk, SOCK_LINGER);
815 release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_no_linger);
818
sock_set_priority(struct sock * sk,u32 priority)819 void sock_set_priority(struct sock *sk, u32 priority)
820 {
821 WRITE_ONCE(sk->sk_priority, priority);
822 }
823 EXPORT_SYMBOL(sock_set_priority);
824
sock_set_sndtimeo(struct sock * sk,s64 secs)825 void sock_set_sndtimeo(struct sock *sk, s64 secs)
826 {
827 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
828 WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
829 else
830 WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
831 }
832 EXPORT_SYMBOL(sock_set_sndtimeo);
833
__sock_set_timestamps(struct sock * sk,bool val,bool new,bool ns)834 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
835 {
836 sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
837 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
838 if (val) {
839 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
840 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
841 }
842 }
843
sock_set_timestamp(struct sock * sk,int optname,bool valbool)844 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
845 {
846 switch (optname) {
847 case SO_TIMESTAMP_OLD:
848 __sock_set_timestamps(sk, valbool, false, false);
849 break;
850 case SO_TIMESTAMP_NEW:
851 __sock_set_timestamps(sk, valbool, true, false);
852 break;
853 case SO_TIMESTAMPNS_OLD:
854 __sock_set_timestamps(sk, valbool, false, true);
855 break;
856 case SO_TIMESTAMPNS_NEW:
857 __sock_set_timestamps(sk, valbool, true, true);
858 break;
859 }
860 }
861
sock_timestamping_bind_phc(struct sock * sk,int phc_index)862 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
863 {
864 struct net *net = sock_net(sk);
865 struct net_device *dev = NULL;
866 bool match = false;
867 int *vclock_index;
868 int i, num;
869
870 if (sk->sk_bound_dev_if)
871 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
872
873 if (!dev) {
874 pr_err("%s: sock not bind to device\n", __func__);
875 return -EOPNOTSUPP;
876 }
877
878 num = ethtool_get_phc_vclocks(dev, &vclock_index);
879 dev_put(dev);
880
881 for (i = 0; i < num; i++) {
882 if (*(vclock_index + i) == phc_index) {
883 match = true;
884 break;
885 }
886 }
887
888 if (num > 0)
889 kfree(vclock_index);
890
891 if (!match)
892 return -EINVAL;
893
894 WRITE_ONCE(sk->sk_bind_phc, phc_index);
895
896 return 0;
897 }
898
sock_set_timestamping(struct sock * sk,int optname,struct so_timestamping timestamping)899 int sock_set_timestamping(struct sock *sk, int optname,
900 struct so_timestamping timestamping)
901 {
902 int val = timestamping.flags;
903 int ret;
904
905 if (val & ~SOF_TIMESTAMPING_MASK)
906 return -EINVAL;
907
908 if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
909 !(val & SOF_TIMESTAMPING_OPT_ID))
910 return -EINVAL;
911
912 if (val & SOF_TIMESTAMPING_OPT_ID &&
913 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
914 if (sk_is_tcp(sk)) {
915 if ((1 << sk->sk_state) &
916 (TCPF_CLOSE | TCPF_LISTEN))
917 return -EINVAL;
918 if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
919 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
920 else
921 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
922 } else {
923 atomic_set(&sk->sk_tskey, 0);
924 }
925 }
926
927 if (val & SOF_TIMESTAMPING_OPT_STATS &&
928 !(val & SOF_TIMESTAMPING_OPT_TSONLY))
929 return -EINVAL;
930
931 if (val & SOF_TIMESTAMPING_BIND_PHC) {
932 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
933 if (ret)
934 return ret;
935 }
936
937 WRITE_ONCE(sk->sk_tsflags, val);
938 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
939 sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
940
941 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
942 sock_enable_timestamp(sk,
943 SOCK_TIMESTAMPING_RX_SOFTWARE);
944 else
945 sock_disable_timestamp(sk,
946 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
947 return 0;
948 }
949
950 #if defined(CONFIG_CGROUP_BPF)
bpf_skops_tx_timestamping(struct sock * sk,struct sk_buff * skb,int op)951 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
952 {
953 struct bpf_sock_ops_kern sock_ops;
954
955 memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
956 sock_ops.op = op;
957 sock_ops.is_fullsock = 1;
958 sock_ops.sk = sk;
959 bpf_skops_init_skb(&sock_ops, skb, 0);
960 __cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
961 }
962 #endif
963
sock_set_keepalive(struct sock * sk)964 void sock_set_keepalive(struct sock *sk)
965 {
966 lock_sock(sk);
967 if (sk->sk_prot->keepalive)
968 sk->sk_prot->keepalive(sk, true);
969 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
970 release_sock(sk);
971 }
972 EXPORT_SYMBOL(sock_set_keepalive);
973
__sock_set_rcvbuf(struct sock * sk,int val)974 static void __sock_set_rcvbuf(struct sock *sk, int val)
975 {
976 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
977 * as a negative value.
978 */
979 val = min_t(int, val, INT_MAX / 2);
980 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
981
982 /* We double it on the way in to account for "struct sk_buff" etc.
983 * overhead. Applications assume that the SO_RCVBUF setting they make
984 * will allow that much actual data to be received on that socket.
985 *
986 * Applications are unaware that "struct sk_buff" and other overheads
987 * allocate from the receive buffer during socket buffer allocation.
988 *
989 * And after considering the possible alternatives, returning the value
990 * we actually used in getsockopt is the most desirable behavior.
991 */
992 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
993 }
994
sock_set_rcvbuf(struct sock * sk,int val)995 void sock_set_rcvbuf(struct sock *sk, int val)
996 {
997 lock_sock(sk);
998 __sock_set_rcvbuf(sk, val);
999 release_sock(sk);
1000 }
1001 EXPORT_SYMBOL(sock_set_rcvbuf);
1002
__sock_set_mark(struct sock * sk,u32 val)1003 static void __sock_set_mark(struct sock *sk, u32 val)
1004 {
1005 if (val != sk->sk_mark) {
1006 WRITE_ONCE(sk->sk_mark, val);
1007 sk_dst_reset(sk);
1008 }
1009 }
1010
sock_set_mark(struct sock * sk,u32 val)1011 void sock_set_mark(struct sock *sk, u32 val)
1012 {
1013 lock_sock(sk);
1014 __sock_set_mark(sk, val);
1015 release_sock(sk);
1016 }
1017 EXPORT_SYMBOL(sock_set_mark);
1018
sock_release_reserved_memory(struct sock * sk,int bytes)1019 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1020 {
1021 /* Round down bytes to multiple of pages */
1022 bytes = round_down(bytes, PAGE_SIZE);
1023
1024 WARN_ON(bytes > sk->sk_reserved_mem);
1025 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1026 sk_mem_reclaim(sk);
1027 }
1028
sock_reserve_memory(struct sock * sk,int bytes)1029 static int sock_reserve_memory(struct sock *sk, int bytes)
1030 {
1031 long allocated;
1032 bool charged;
1033 int pages;
1034
1035 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1036 return -EOPNOTSUPP;
1037
1038 if (!bytes)
1039 return 0;
1040
1041 pages = sk_mem_pages(bytes);
1042
1043 /* pre-charge to memcg */
1044 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1045 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1046 if (!charged)
1047 return -ENOMEM;
1048
1049 /* pre-charge to forward_alloc */
1050 sk_memory_allocated_add(sk, pages);
1051 allocated = sk_memory_allocated(sk);
1052 /* If the system goes into memory pressure with this
1053 * precharge, give up and return error.
1054 */
1055 if (allocated > sk_prot_mem_limits(sk, 1)) {
1056 sk_memory_allocated_sub(sk, pages);
1057 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1058 return -ENOMEM;
1059 }
1060 sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1061
1062 WRITE_ONCE(sk->sk_reserved_mem,
1063 sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1064
1065 return 0;
1066 }
1067
1068 #ifdef CONFIG_PAGE_POOL
1069
1070 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1071 * in 1 syscall. The limit exists to limit the amount of memory the kernel
1072 * allocates to copy these tokens, and to prevent looping over the frags for
1073 * too long.
1074 */
1075 #define MAX_DONTNEED_TOKENS 128
1076 #define MAX_DONTNEED_FRAGS 1024
1077
1078 static noinline_for_stack int
sock_devmem_dontneed(struct sock * sk,sockptr_t optval,unsigned int optlen)1079 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1080 {
1081 unsigned int num_tokens, i, j, k, netmem_num = 0;
1082 struct dmabuf_token *tokens;
1083 int ret = 0, num_frags = 0;
1084 netmem_ref netmems[16];
1085
1086 if (!sk_is_tcp(sk))
1087 return -EBADF;
1088
1089 if (optlen % sizeof(*tokens) ||
1090 optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1091 return -EINVAL;
1092
1093 num_tokens = optlen / sizeof(*tokens);
1094 tokens = kvmalloc_array(num_tokens, sizeof(*tokens), GFP_KERNEL);
1095 if (!tokens)
1096 return -ENOMEM;
1097
1098 if (copy_from_sockptr(tokens, optval, optlen)) {
1099 kvfree(tokens);
1100 return -EFAULT;
1101 }
1102
1103 xa_lock_bh(&sk->sk_user_frags);
1104 for (i = 0; i < num_tokens; i++) {
1105 for (j = 0; j < tokens[i].token_count; j++) {
1106 if (++num_frags > MAX_DONTNEED_FRAGS)
1107 goto frag_limit_reached;
1108
1109 netmem_ref netmem = (__force netmem_ref)__xa_erase(
1110 &sk->sk_user_frags, tokens[i].token_start + j);
1111
1112 if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1113 continue;
1114
1115 netmems[netmem_num++] = netmem;
1116 if (netmem_num == ARRAY_SIZE(netmems)) {
1117 xa_unlock_bh(&sk->sk_user_frags);
1118 for (k = 0; k < netmem_num; k++)
1119 WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1120 netmem_num = 0;
1121 xa_lock_bh(&sk->sk_user_frags);
1122 }
1123 ret++;
1124 }
1125 }
1126
1127 frag_limit_reached:
1128 xa_unlock_bh(&sk->sk_user_frags);
1129 for (k = 0; k < netmem_num; k++)
1130 WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1131
1132 kvfree(tokens);
1133 return ret;
1134 }
1135 #endif
1136
sockopt_lock_sock(struct sock * sk)1137 void sockopt_lock_sock(struct sock *sk)
1138 {
1139 /* When current->bpf_ctx is set, the setsockopt is called from
1140 * a bpf prog. bpf has ensured the sk lock has been
1141 * acquired before calling setsockopt().
1142 */
1143 if (has_current_bpf_ctx())
1144 return;
1145
1146 lock_sock(sk);
1147 }
1148 EXPORT_SYMBOL(sockopt_lock_sock);
1149
sockopt_release_sock(struct sock * sk)1150 void sockopt_release_sock(struct sock *sk)
1151 {
1152 if (has_current_bpf_ctx())
1153 return;
1154
1155 release_sock(sk);
1156 }
1157 EXPORT_SYMBOL(sockopt_release_sock);
1158
sockopt_ns_capable(struct user_namespace * ns,int cap)1159 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1160 {
1161 return has_current_bpf_ctx() || ns_capable(ns, cap);
1162 }
1163 EXPORT_SYMBOL(sockopt_ns_capable);
1164
sockopt_capable(int cap)1165 bool sockopt_capable(int cap)
1166 {
1167 return has_current_bpf_ctx() || capable(cap);
1168 }
1169 EXPORT_SYMBOL(sockopt_capable);
1170
sockopt_validate_clockid(__kernel_clockid_t value)1171 static int sockopt_validate_clockid(__kernel_clockid_t value)
1172 {
1173 switch (value) {
1174 case CLOCK_REALTIME:
1175 case CLOCK_MONOTONIC:
1176 case CLOCK_TAI:
1177 return 0;
1178 }
1179 return -EINVAL;
1180 }
1181
1182 /*
1183 * This is meant for all protocols to use and covers goings on
1184 * at the socket level. Everything here is generic.
1185 */
1186
sk_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)1187 int sk_setsockopt(struct sock *sk, int level, int optname,
1188 sockptr_t optval, unsigned int optlen)
1189 {
1190 struct so_timestamping timestamping;
1191 struct socket *sock = sk->sk_socket;
1192 struct sock_txtime sk_txtime;
1193 int val;
1194 int valbool;
1195 struct linger ling;
1196 int ret = 0;
1197
1198 /*
1199 * Options without arguments
1200 */
1201
1202 if (optname == SO_BINDTODEVICE)
1203 return sock_setbindtodevice(sk, optval, optlen);
1204
1205 if (optlen < sizeof(int))
1206 return -EINVAL;
1207
1208 if (copy_from_sockptr(&val, optval, sizeof(val)))
1209 return -EFAULT;
1210
1211 valbool = val ? 1 : 0;
1212
1213 /* handle options which do not require locking the socket. */
1214 switch (optname) {
1215 case SO_PRIORITY:
1216 if (sk_set_prio_allowed(sk, val)) {
1217 sock_set_priority(sk, val);
1218 return 0;
1219 }
1220 return -EPERM;
1221 case SO_TYPE:
1222 case SO_PROTOCOL:
1223 case SO_DOMAIN:
1224 case SO_ERROR:
1225 return -ENOPROTOOPT;
1226 #ifdef CONFIG_NET_RX_BUSY_POLL
1227 case SO_BUSY_POLL:
1228 if (val < 0)
1229 return -EINVAL;
1230 WRITE_ONCE(sk->sk_ll_usec, val);
1231 return 0;
1232 case SO_PREFER_BUSY_POLL:
1233 if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1234 return -EPERM;
1235 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1236 return 0;
1237 case SO_BUSY_POLL_BUDGET:
1238 if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1239 !sockopt_capable(CAP_NET_ADMIN))
1240 return -EPERM;
1241 if (val < 0 || val > U16_MAX)
1242 return -EINVAL;
1243 WRITE_ONCE(sk->sk_busy_poll_budget, val);
1244 return 0;
1245 #endif
1246 case SO_MAX_PACING_RATE:
1247 {
1248 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1249 unsigned long pacing_rate;
1250
1251 if (sizeof(ulval) != sizeof(val) &&
1252 optlen >= sizeof(ulval) &&
1253 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1254 return -EFAULT;
1255 }
1256 if (ulval != ~0UL)
1257 cmpxchg(&sk->sk_pacing_status,
1258 SK_PACING_NONE,
1259 SK_PACING_NEEDED);
1260 /* Pairs with READ_ONCE() from sk_getsockopt() */
1261 WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1262 pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1263 if (ulval < pacing_rate)
1264 WRITE_ONCE(sk->sk_pacing_rate, ulval);
1265 return 0;
1266 }
1267 case SO_TXREHASH:
1268 if (!sk_is_tcp(sk))
1269 return -EOPNOTSUPP;
1270 if (val < -1 || val > 1)
1271 return -EINVAL;
1272 if ((u8)val == SOCK_TXREHASH_DEFAULT)
1273 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1274 /* Paired with READ_ONCE() in tcp_rtx_synack()
1275 * and sk_getsockopt().
1276 */
1277 WRITE_ONCE(sk->sk_txrehash, (u8)val);
1278 return 0;
1279 case SO_PEEK_OFF:
1280 {
1281 int (*set_peek_off)(struct sock *sk, int val);
1282
1283 set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1284 if (set_peek_off)
1285 ret = set_peek_off(sk, val);
1286 else
1287 ret = -EOPNOTSUPP;
1288 return ret;
1289 }
1290 #ifdef CONFIG_PAGE_POOL
1291 case SO_DEVMEM_DONTNEED:
1292 return sock_devmem_dontneed(sk, optval, optlen);
1293 #endif
1294 case SO_SNDTIMEO_OLD:
1295 case SO_SNDTIMEO_NEW:
1296 return sock_set_timeout(&sk->sk_sndtimeo, optval,
1297 optlen, optname == SO_SNDTIMEO_OLD);
1298 case SO_RCVTIMEO_OLD:
1299 case SO_RCVTIMEO_NEW:
1300 return sock_set_timeout(&sk->sk_rcvtimeo, optval,
1301 optlen, optname == SO_RCVTIMEO_OLD);
1302 }
1303
1304 sockopt_lock_sock(sk);
1305
1306 switch (optname) {
1307 case SO_DEBUG:
1308 if (val && !sockopt_capable(CAP_NET_ADMIN))
1309 ret = -EACCES;
1310 else
1311 sock_valbool_flag(sk, SOCK_DBG, valbool);
1312 break;
1313 case SO_REUSEADDR:
1314 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1315 break;
1316 case SO_REUSEPORT:
1317 if (valbool && !sk_is_inet(sk))
1318 ret = -EOPNOTSUPP;
1319 else
1320 sk->sk_reuseport = valbool;
1321 break;
1322 case SO_DONTROUTE:
1323 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1324 sk_dst_reset(sk);
1325 break;
1326 case SO_BROADCAST:
1327 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1328 break;
1329 case SO_SNDBUF:
1330 /* Don't error on this BSD doesn't and if you think
1331 * about it this is right. Otherwise apps have to
1332 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1333 * are treated in BSD as hints
1334 */
1335 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1336 set_sndbuf:
1337 /* Ensure val * 2 fits into an int, to prevent max_t()
1338 * from treating it as a negative value.
1339 */
1340 val = min_t(int, val, INT_MAX / 2);
1341 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1342 WRITE_ONCE(sk->sk_sndbuf,
1343 max_t(int, val * 2, SOCK_MIN_SNDBUF));
1344 /* Wake up sending tasks if we upped the value. */
1345 sk->sk_write_space(sk);
1346 break;
1347
1348 case SO_SNDBUFFORCE:
1349 if (!sockopt_capable(CAP_NET_ADMIN)) {
1350 ret = -EPERM;
1351 break;
1352 }
1353
1354 /* No negative values (to prevent underflow, as val will be
1355 * multiplied by 2).
1356 */
1357 if (val < 0)
1358 val = 0;
1359 goto set_sndbuf;
1360
1361 case SO_RCVBUF:
1362 /* Don't error on this BSD doesn't and if you think
1363 * about it this is right. Otherwise apps have to
1364 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1365 * are treated in BSD as hints
1366 */
1367 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1368 break;
1369
1370 case SO_RCVBUFFORCE:
1371 if (!sockopt_capable(CAP_NET_ADMIN)) {
1372 ret = -EPERM;
1373 break;
1374 }
1375
1376 /* No negative values (to prevent underflow, as val will be
1377 * multiplied by 2).
1378 */
1379 __sock_set_rcvbuf(sk, max(val, 0));
1380 break;
1381
1382 case SO_KEEPALIVE:
1383 if (sk->sk_prot->keepalive)
1384 sk->sk_prot->keepalive(sk, valbool);
1385 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1386 break;
1387
1388 case SO_OOBINLINE:
1389 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1390 break;
1391
1392 case SO_NO_CHECK:
1393 sk->sk_no_check_tx = valbool;
1394 break;
1395
1396 case SO_LINGER:
1397 if (optlen < sizeof(ling)) {
1398 ret = -EINVAL; /* 1003.1g */
1399 break;
1400 }
1401 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1402 ret = -EFAULT;
1403 break;
1404 }
1405 if (!ling.l_onoff) {
1406 sock_reset_flag(sk, SOCK_LINGER);
1407 } else {
1408 unsigned long t_sec = ling.l_linger;
1409
1410 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1411 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1412 else
1413 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1414 sock_set_flag(sk, SOCK_LINGER);
1415 }
1416 break;
1417
1418 case SO_BSDCOMPAT:
1419 break;
1420
1421 case SO_TIMESTAMP_OLD:
1422 case SO_TIMESTAMP_NEW:
1423 case SO_TIMESTAMPNS_OLD:
1424 case SO_TIMESTAMPNS_NEW:
1425 sock_set_timestamp(sk, optname, valbool);
1426 break;
1427
1428 case SO_TIMESTAMPING_NEW:
1429 case SO_TIMESTAMPING_OLD:
1430 if (optlen == sizeof(timestamping)) {
1431 if (copy_from_sockptr(×tamping, optval,
1432 sizeof(timestamping))) {
1433 ret = -EFAULT;
1434 break;
1435 }
1436 } else {
1437 memset(×tamping, 0, sizeof(timestamping));
1438 timestamping.flags = val;
1439 }
1440 ret = sock_set_timestamping(sk, optname, timestamping);
1441 break;
1442
1443 case SO_RCVLOWAT:
1444 {
1445 int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1446
1447 if (val < 0)
1448 val = INT_MAX;
1449 if (sock)
1450 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1451 if (set_rcvlowat)
1452 ret = set_rcvlowat(sk, val);
1453 else
1454 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1455 break;
1456 }
1457 case SO_ATTACH_FILTER: {
1458 struct sock_fprog fprog;
1459
1460 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1461 if (!ret)
1462 ret = sk_attach_filter(&fprog, sk);
1463 break;
1464 }
1465 case SO_ATTACH_BPF:
1466 ret = -EINVAL;
1467 if (optlen == sizeof(u32)) {
1468 u32 ufd;
1469
1470 ret = -EFAULT;
1471 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1472 break;
1473
1474 ret = sk_attach_bpf(ufd, sk);
1475 }
1476 break;
1477
1478 case SO_ATTACH_REUSEPORT_CBPF: {
1479 struct sock_fprog fprog;
1480
1481 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1482 if (!ret)
1483 ret = sk_reuseport_attach_filter(&fprog, sk);
1484 break;
1485 }
1486 case SO_ATTACH_REUSEPORT_EBPF:
1487 ret = -EINVAL;
1488 if (optlen == sizeof(u32)) {
1489 u32 ufd;
1490
1491 ret = -EFAULT;
1492 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1493 break;
1494
1495 ret = sk_reuseport_attach_bpf(ufd, sk);
1496 }
1497 break;
1498
1499 case SO_DETACH_REUSEPORT_BPF:
1500 ret = reuseport_detach_prog(sk);
1501 break;
1502
1503 case SO_DETACH_FILTER:
1504 ret = sk_detach_filter(sk);
1505 break;
1506
1507 case SO_LOCK_FILTER:
1508 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1509 ret = -EPERM;
1510 else
1511 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1512 break;
1513
1514 case SO_MARK:
1515 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1516 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1517 ret = -EPERM;
1518 break;
1519 }
1520
1521 __sock_set_mark(sk, val);
1522 break;
1523 case SO_RCVMARK:
1524 sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1525 break;
1526
1527 case SO_RCVPRIORITY:
1528 sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1529 break;
1530
1531 case SO_RXQ_OVFL:
1532 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1533 break;
1534
1535 case SO_WIFI_STATUS:
1536 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1537 break;
1538
1539 case SO_NOFCS:
1540 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1541 break;
1542
1543 case SO_SELECT_ERR_QUEUE:
1544 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1545 break;
1546
1547 case SO_PASSCRED:
1548 if (sk_may_scm_recv(sk))
1549 sk->sk_scm_credentials = valbool;
1550 else
1551 ret = -EOPNOTSUPP;
1552 break;
1553
1554 case SO_PASSSEC:
1555 if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk))
1556 sk->sk_scm_security = valbool;
1557 else
1558 ret = -EOPNOTSUPP;
1559 break;
1560
1561 case SO_PASSPIDFD:
1562 if (sk_is_unix(sk))
1563 sk->sk_scm_pidfd = valbool;
1564 else
1565 ret = -EOPNOTSUPP;
1566 break;
1567
1568 case SO_PASSRIGHTS:
1569 if (sk_is_unix(sk))
1570 sk->sk_scm_rights = valbool;
1571 else
1572 ret = -EOPNOTSUPP;
1573 break;
1574
1575 case SO_INCOMING_CPU:
1576 reuseport_update_incoming_cpu(sk, val);
1577 break;
1578
1579 case SO_CNX_ADVICE:
1580 if (val == 1)
1581 dst_negative_advice(sk);
1582 break;
1583
1584 case SO_ZEROCOPY:
1585 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1586 if (!(sk_is_tcp(sk) ||
1587 (sk->sk_type == SOCK_DGRAM &&
1588 sk->sk_protocol == IPPROTO_UDP)))
1589 ret = -EOPNOTSUPP;
1590 } else if (sk->sk_family != PF_RDS) {
1591 ret = -EOPNOTSUPP;
1592 }
1593 if (!ret) {
1594 if (val < 0 || val > 1)
1595 ret = -EINVAL;
1596 else
1597 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1598 }
1599 break;
1600
1601 case SO_TXTIME:
1602 if (optlen != sizeof(struct sock_txtime)) {
1603 ret = -EINVAL;
1604 break;
1605 } else if (copy_from_sockptr(&sk_txtime, optval,
1606 sizeof(struct sock_txtime))) {
1607 ret = -EFAULT;
1608 break;
1609 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1610 ret = -EINVAL;
1611 break;
1612 }
1613 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1614 * scheduler has enough safe guards.
1615 */
1616 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1617 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1618 ret = -EPERM;
1619 break;
1620 }
1621
1622 ret = sockopt_validate_clockid(sk_txtime.clockid);
1623 if (ret)
1624 break;
1625
1626 sock_valbool_flag(sk, SOCK_TXTIME, true);
1627 sk->sk_clockid = sk_txtime.clockid;
1628 sk->sk_txtime_deadline_mode =
1629 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1630 sk->sk_txtime_report_errors =
1631 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1632 break;
1633
1634 case SO_BINDTOIFINDEX:
1635 ret = sock_bindtoindex_locked(sk, val);
1636 break;
1637
1638 case SO_BUF_LOCK:
1639 if (val & ~SOCK_BUF_LOCK_MASK) {
1640 ret = -EINVAL;
1641 break;
1642 }
1643 sk->sk_userlocks = val | (sk->sk_userlocks &
1644 ~SOCK_BUF_LOCK_MASK);
1645 break;
1646
1647 case SO_RESERVE_MEM:
1648 {
1649 int delta;
1650
1651 if (val < 0) {
1652 ret = -EINVAL;
1653 break;
1654 }
1655
1656 delta = val - sk->sk_reserved_mem;
1657 if (delta < 0)
1658 sock_release_reserved_memory(sk, -delta);
1659 else
1660 ret = sock_reserve_memory(sk, delta);
1661 break;
1662 }
1663
1664 default:
1665 ret = -ENOPROTOOPT;
1666 break;
1667 }
1668 sockopt_release_sock(sk);
1669 return ret;
1670 }
1671
sock_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1672 int sock_setsockopt(struct socket *sock, int level, int optname,
1673 sockptr_t optval, unsigned int optlen)
1674 {
1675 return sk_setsockopt(sock->sk, level, optname,
1676 optval, optlen);
1677 }
1678 EXPORT_SYMBOL(sock_setsockopt);
1679
sk_get_peer_cred(struct sock * sk)1680 static const struct cred *sk_get_peer_cred(struct sock *sk)
1681 {
1682 const struct cred *cred;
1683
1684 spin_lock(&sk->sk_peer_lock);
1685 cred = get_cred(sk->sk_peer_cred);
1686 spin_unlock(&sk->sk_peer_lock);
1687
1688 return cred;
1689 }
1690
cred_to_ucred(struct pid * pid,const struct cred * cred,struct ucred * ucred)1691 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1692 struct ucred *ucred)
1693 {
1694 ucred->pid = pid_vnr(pid);
1695 ucred->uid = ucred->gid = -1;
1696 if (cred) {
1697 struct user_namespace *current_ns = current_user_ns();
1698
1699 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1700 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1701 }
1702 }
1703
groups_to_user(sockptr_t dst,const struct group_info * src)1704 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1705 {
1706 struct user_namespace *user_ns = current_user_ns();
1707 int i;
1708
1709 for (i = 0; i < src->ngroups; i++) {
1710 gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1711
1712 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1713 return -EFAULT;
1714 }
1715
1716 return 0;
1717 }
1718
sk_getsockopt(struct sock * sk,int level,int optname,sockptr_t optval,sockptr_t optlen)1719 int sk_getsockopt(struct sock *sk, int level, int optname,
1720 sockptr_t optval, sockptr_t optlen)
1721 {
1722 struct socket *sock = sk->sk_socket;
1723
1724 union {
1725 int val;
1726 u64 val64;
1727 unsigned long ulval;
1728 struct linger ling;
1729 struct old_timeval32 tm32;
1730 struct __kernel_old_timeval tm;
1731 struct __kernel_sock_timeval stm;
1732 struct sock_txtime txtime;
1733 struct so_timestamping timestamping;
1734 } v;
1735
1736 int lv = sizeof(int);
1737 int len;
1738
1739 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1740 return -EFAULT;
1741 if (len < 0)
1742 return -EINVAL;
1743
1744 memset(&v, 0, sizeof(v));
1745
1746 switch (optname) {
1747 case SO_DEBUG:
1748 v.val = sock_flag(sk, SOCK_DBG);
1749 break;
1750
1751 case SO_DONTROUTE:
1752 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1753 break;
1754
1755 case SO_BROADCAST:
1756 v.val = sock_flag(sk, SOCK_BROADCAST);
1757 break;
1758
1759 case SO_SNDBUF:
1760 v.val = READ_ONCE(sk->sk_sndbuf);
1761 break;
1762
1763 case SO_RCVBUF:
1764 v.val = READ_ONCE(sk->sk_rcvbuf);
1765 break;
1766
1767 case SO_REUSEADDR:
1768 v.val = sk->sk_reuse;
1769 break;
1770
1771 case SO_REUSEPORT:
1772 v.val = sk->sk_reuseport;
1773 break;
1774
1775 case SO_KEEPALIVE:
1776 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1777 break;
1778
1779 case SO_TYPE:
1780 v.val = sk->sk_type;
1781 break;
1782
1783 case SO_PROTOCOL:
1784 v.val = sk->sk_protocol;
1785 break;
1786
1787 case SO_DOMAIN:
1788 v.val = sk->sk_family;
1789 break;
1790
1791 case SO_ERROR:
1792 v.val = -sock_error(sk);
1793 if (v.val == 0)
1794 v.val = xchg(&sk->sk_err_soft, 0);
1795 break;
1796
1797 case SO_OOBINLINE:
1798 v.val = sock_flag(sk, SOCK_URGINLINE);
1799 break;
1800
1801 case SO_NO_CHECK:
1802 v.val = sk->sk_no_check_tx;
1803 break;
1804
1805 case SO_PRIORITY:
1806 v.val = READ_ONCE(sk->sk_priority);
1807 break;
1808
1809 case SO_LINGER:
1810 lv = sizeof(v.ling);
1811 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1812 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ;
1813 break;
1814
1815 case SO_BSDCOMPAT:
1816 break;
1817
1818 case SO_TIMESTAMP_OLD:
1819 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1820 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1821 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1822 break;
1823
1824 case SO_TIMESTAMPNS_OLD:
1825 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1826 break;
1827
1828 case SO_TIMESTAMP_NEW:
1829 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1830 break;
1831
1832 case SO_TIMESTAMPNS_NEW:
1833 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1834 break;
1835
1836 case SO_TIMESTAMPING_OLD:
1837 case SO_TIMESTAMPING_NEW:
1838 lv = sizeof(v.timestamping);
1839 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1840 * returning the flags when they were set through the same option.
1841 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1842 */
1843 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1844 v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1845 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1846 }
1847 break;
1848
1849 case SO_RCVTIMEO_OLD:
1850 case SO_RCVTIMEO_NEW:
1851 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1852 SO_RCVTIMEO_OLD == optname);
1853 break;
1854
1855 case SO_SNDTIMEO_OLD:
1856 case SO_SNDTIMEO_NEW:
1857 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1858 SO_SNDTIMEO_OLD == optname);
1859 break;
1860
1861 case SO_RCVLOWAT:
1862 v.val = READ_ONCE(sk->sk_rcvlowat);
1863 break;
1864
1865 case SO_SNDLOWAT:
1866 v.val = 1;
1867 break;
1868
1869 case SO_PASSCRED:
1870 if (!sk_may_scm_recv(sk))
1871 return -EOPNOTSUPP;
1872
1873 v.val = sk->sk_scm_credentials;
1874 break;
1875
1876 case SO_PASSPIDFD:
1877 if (!sk_is_unix(sk))
1878 return -EOPNOTSUPP;
1879
1880 v.val = sk->sk_scm_pidfd;
1881 break;
1882
1883 case SO_PASSRIGHTS:
1884 if (!sk_is_unix(sk))
1885 return -EOPNOTSUPP;
1886
1887 v.val = sk->sk_scm_rights;
1888 break;
1889
1890 case SO_PEERCRED:
1891 {
1892 struct ucred peercred;
1893 if (len > sizeof(peercred))
1894 len = sizeof(peercred);
1895
1896 spin_lock(&sk->sk_peer_lock);
1897 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1898 spin_unlock(&sk->sk_peer_lock);
1899
1900 if (copy_to_sockptr(optval, &peercred, len))
1901 return -EFAULT;
1902 goto lenout;
1903 }
1904
1905 case SO_PEERPIDFD:
1906 {
1907 struct pid *peer_pid;
1908 struct file *pidfd_file = NULL;
1909 unsigned int flags = 0;
1910 int pidfd;
1911
1912 if (len > sizeof(pidfd))
1913 len = sizeof(pidfd);
1914
1915 spin_lock(&sk->sk_peer_lock);
1916 peer_pid = get_pid(sk->sk_peer_pid);
1917 spin_unlock(&sk->sk_peer_lock);
1918
1919 if (!peer_pid)
1920 return -ENODATA;
1921
1922 /* The use of PIDFD_STALE requires stashing of struct pid
1923 * on pidfs with pidfs_register_pid() and only AF_UNIX
1924 * were prepared for this.
1925 */
1926 if (sk->sk_family == AF_UNIX)
1927 flags = PIDFD_STALE;
1928
1929 pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1930 put_pid(peer_pid);
1931 if (pidfd < 0)
1932 return pidfd;
1933
1934 if (copy_to_sockptr(optval, &pidfd, len) ||
1935 copy_to_sockptr(optlen, &len, sizeof(int))) {
1936 put_unused_fd(pidfd);
1937 fput(pidfd_file);
1938
1939 return -EFAULT;
1940 }
1941
1942 fd_install(pidfd, pidfd_file);
1943 return 0;
1944 }
1945
1946 case SO_PEERGROUPS:
1947 {
1948 const struct cred *cred;
1949 int ret, n;
1950
1951 cred = sk_get_peer_cred(sk);
1952 if (!cred)
1953 return -ENODATA;
1954
1955 n = cred->group_info->ngroups;
1956 if (len < n * sizeof(gid_t)) {
1957 len = n * sizeof(gid_t);
1958 put_cred(cred);
1959 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1960 }
1961 len = n * sizeof(gid_t);
1962
1963 ret = groups_to_user(optval, cred->group_info);
1964 put_cred(cred);
1965 if (ret)
1966 return ret;
1967 goto lenout;
1968 }
1969
1970 case SO_PEERNAME:
1971 {
1972 struct sockaddr_storage address;
1973
1974 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1975 if (lv < 0)
1976 return -ENOTCONN;
1977 if (lv < len)
1978 return -EINVAL;
1979 if (copy_to_sockptr(optval, &address, len))
1980 return -EFAULT;
1981 goto lenout;
1982 }
1983
1984 /* Dubious BSD thing... Probably nobody even uses it, but
1985 * the UNIX standard wants it for whatever reason... -DaveM
1986 */
1987 case SO_ACCEPTCONN:
1988 v.val = sk->sk_state == TCP_LISTEN;
1989 break;
1990
1991 case SO_PASSSEC:
1992 if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk))
1993 return -EOPNOTSUPP;
1994
1995 v.val = sk->sk_scm_security;
1996 break;
1997
1998 case SO_PEERSEC:
1999 return security_socket_getpeersec_stream(sock,
2000 optval, optlen, len);
2001
2002 case SO_MARK:
2003 v.val = READ_ONCE(sk->sk_mark);
2004 break;
2005
2006 case SO_RCVMARK:
2007 v.val = sock_flag(sk, SOCK_RCVMARK);
2008 break;
2009
2010 case SO_RCVPRIORITY:
2011 v.val = sock_flag(sk, SOCK_RCVPRIORITY);
2012 break;
2013
2014 case SO_RXQ_OVFL:
2015 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
2016 break;
2017
2018 case SO_WIFI_STATUS:
2019 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
2020 break;
2021
2022 case SO_PEEK_OFF:
2023 if (!READ_ONCE(sock->ops)->set_peek_off)
2024 return -EOPNOTSUPP;
2025
2026 v.val = READ_ONCE(sk->sk_peek_off);
2027 break;
2028 case SO_NOFCS:
2029 v.val = sock_flag(sk, SOCK_NOFCS);
2030 break;
2031
2032 case SO_BINDTODEVICE:
2033 return sock_getbindtodevice(sk, optval, optlen, len);
2034
2035 case SO_GET_FILTER:
2036 len = sk_get_filter(sk, optval, len);
2037 if (len < 0)
2038 return len;
2039
2040 goto lenout;
2041
2042 case SO_LOCK_FILTER:
2043 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2044 break;
2045
2046 case SO_BPF_EXTENSIONS:
2047 v.val = bpf_tell_extensions();
2048 break;
2049
2050 case SO_SELECT_ERR_QUEUE:
2051 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2052 break;
2053
2054 #ifdef CONFIG_NET_RX_BUSY_POLL
2055 case SO_BUSY_POLL:
2056 v.val = READ_ONCE(sk->sk_ll_usec);
2057 break;
2058 case SO_PREFER_BUSY_POLL:
2059 v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2060 break;
2061 #endif
2062
2063 case SO_MAX_PACING_RATE:
2064 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2065 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2066 lv = sizeof(v.ulval);
2067 v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2068 } else {
2069 /* 32bit version */
2070 v.val = min_t(unsigned long, ~0U,
2071 READ_ONCE(sk->sk_max_pacing_rate));
2072 }
2073 break;
2074
2075 case SO_INCOMING_CPU:
2076 v.val = READ_ONCE(sk->sk_incoming_cpu);
2077 break;
2078
2079 case SO_MEMINFO:
2080 {
2081 u32 meminfo[SK_MEMINFO_VARS];
2082
2083 sk_get_meminfo(sk, meminfo);
2084
2085 len = min_t(unsigned int, len, sizeof(meminfo));
2086 if (copy_to_sockptr(optval, &meminfo, len))
2087 return -EFAULT;
2088
2089 goto lenout;
2090 }
2091
2092 #ifdef CONFIG_NET_RX_BUSY_POLL
2093 case SO_INCOMING_NAPI_ID:
2094 v.val = READ_ONCE(sk->sk_napi_id);
2095
2096 /* aggregate non-NAPI IDs down to 0 */
2097 if (!napi_id_valid(v.val))
2098 v.val = 0;
2099
2100 break;
2101 #endif
2102
2103 case SO_COOKIE:
2104 lv = sizeof(u64);
2105 if (len < lv)
2106 return -EINVAL;
2107 v.val64 = sock_gen_cookie(sk);
2108 break;
2109
2110 case SO_ZEROCOPY:
2111 v.val = sock_flag(sk, SOCK_ZEROCOPY);
2112 break;
2113
2114 case SO_TXTIME:
2115 lv = sizeof(v.txtime);
2116 v.txtime.clockid = sk->sk_clockid;
2117 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2118 SOF_TXTIME_DEADLINE_MODE : 0;
2119 v.txtime.flags |= sk->sk_txtime_report_errors ?
2120 SOF_TXTIME_REPORT_ERRORS : 0;
2121 break;
2122
2123 case SO_BINDTOIFINDEX:
2124 v.val = READ_ONCE(sk->sk_bound_dev_if);
2125 break;
2126
2127 case SO_NETNS_COOKIE:
2128 lv = sizeof(u64);
2129 if (len != lv)
2130 return -EINVAL;
2131 v.val64 = sock_net(sk)->net_cookie;
2132 break;
2133
2134 case SO_BUF_LOCK:
2135 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2136 break;
2137
2138 case SO_RESERVE_MEM:
2139 v.val = READ_ONCE(sk->sk_reserved_mem);
2140 break;
2141
2142 case SO_TXREHASH:
2143 if (!sk_is_tcp(sk))
2144 return -EOPNOTSUPP;
2145
2146 /* Paired with WRITE_ONCE() in sk_setsockopt() */
2147 v.val = READ_ONCE(sk->sk_txrehash);
2148 break;
2149
2150 default:
2151 /* We implement the SO_SNDLOWAT etc to not be settable
2152 * (1003.1g 7).
2153 */
2154 return -ENOPROTOOPT;
2155 }
2156
2157 if (len > lv)
2158 len = lv;
2159 if (copy_to_sockptr(optval, &v, len))
2160 return -EFAULT;
2161 lenout:
2162 if (copy_to_sockptr(optlen, &len, sizeof(int)))
2163 return -EFAULT;
2164 return 0;
2165 }
2166
2167 /*
2168 * Initialize an sk_lock.
2169 *
2170 * (We also register the sk_lock with the lock validator.)
2171 */
sock_lock_init(struct sock * sk)2172 static inline void sock_lock_init(struct sock *sk)
2173 {
2174 sk_owner_clear(sk);
2175
2176 if (sk->sk_kern_sock)
2177 sock_lock_init_class_and_name(
2178 sk,
2179 af_family_kern_slock_key_strings[sk->sk_family],
2180 af_family_kern_slock_keys + sk->sk_family,
2181 af_family_kern_key_strings[sk->sk_family],
2182 af_family_kern_keys + sk->sk_family);
2183 else
2184 sock_lock_init_class_and_name(
2185 sk,
2186 af_family_slock_key_strings[sk->sk_family],
2187 af_family_slock_keys + sk->sk_family,
2188 af_family_key_strings[sk->sk_family],
2189 af_family_keys + sk->sk_family);
2190 }
2191
2192 /*
2193 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2194 * even temporarily, because of RCU lookups. sk_node should also be left as is.
2195 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2196 */
sock_copy(struct sock * nsk,const struct sock * osk)2197 static void sock_copy(struct sock *nsk, const struct sock *osk)
2198 {
2199 const struct proto *prot = READ_ONCE(osk->sk_prot);
2200 #ifdef CONFIG_SECURITY_NETWORK
2201 void *sptr = nsk->sk_security;
2202 #endif
2203
2204 /* If we move sk_tx_queue_mapping out of the private section,
2205 * we must check if sk_tx_queue_clear() is called after
2206 * sock_copy() in sk_clone_lock().
2207 */
2208 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2209 offsetof(struct sock, sk_dontcopy_begin) ||
2210 offsetof(struct sock, sk_tx_queue_mapping) >=
2211 offsetof(struct sock, sk_dontcopy_end));
2212
2213 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2214
2215 unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2216 prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2217 /* alloc is larger than struct, see sk_prot_alloc() */);
2218
2219 #ifdef CONFIG_SECURITY_NETWORK
2220 nsk->sk_security = sptr;
2221 security_sk_clone(osk, nsk);
2222 #endif
2223 }
2224
sk_prot_alloc(struct proto * prot,gfp_t priority,int family)2225 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2226 int family)
2227 {
2228 struct sock *sk;
2229 struct kmem_cache *slab;
2230
2231 slab = prot->slab;
2232 if (slab != NULL) {
2233 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2234 if (!sk)
2235 return sk;
2236 if (want_init_on_alloc(priority))
2237 sk_prot_clear_nulls(sk, prot->obj_size);
2238 } else
2239 sk = kmalloc(prot->obj_size, priority);
2240
2241 if (sk != NULL) {
2242 if (security_sk_alloc(sk, family, priority))
2243 goto out_free;
2244
2245 if (!try_module_get(prot->owner))
2246 goto out_free_sec;
2247 }
2248
2249 return sk;
2250
2251 out_free_sec:
2252 security_sk_free(sk);
2253 out_free:
2254 if (slab != NULL)
2255 kmem_cache_free(slab, sk);
2256 else
2257 kfree(sk);
2258 return NULL;
2259 }
2260
sk_prot_free(struct proto * prot,struct sock * sk)2261 static void sk_prot_free(struct proto *prot, struct sock *sk)
2262 {
2263 struct kmem_cache *slab;
2264 struct module *owner;
2265
2266 owner = prot->owner;
2267 slab = prot->slab;
2268
2269 cgroup_sk_free(&sk->sk_cgrp_data);
2270 mem_cgroup_sk_free(sk);
2271 security_sk_free(sk);
2272
2273 sk_owner_put(sk);
2274
2275 if (slab != NULL)
2276 kmem_cache_free(slab, sk);
2277 else
2278 kfree(sk);
2279 module_put(owner);
2280 }
2281
2282 /**
2283 * sk_alloc - All socket objects are allocated here
2284 * @net: the applicable net namespace
2285 * @family: protocol family
2286 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2287 * @prot: struct proto associated with this new sock instance
2288 * @kern: is this to be a kernel socket?
2289 */
sk_alloc(struct net * net,int family,gfp_t priority,struct proto * prot,int kern)2290 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2291 struct proto *prot, int kern)
2292 {
2293 struct sock *sk;
2294
2295 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2296 if (sk) {
2297 sk->sk_family = family;
2298 /*
2299 * See comment in struct sock definition to understand
2300 * why we need sk_prot_creator -acme
2301 */
2302 sk->sk_prot = sk->sk_prot_creator = prot;
2303 sk->sk_kern_sock = kern;
2304 sock_lock_init(sk);
2305 sk->sk_net_refcnt = kern ? 0 : 1;
2306 if (likely(sk->sk_net_refcnt)) {
2307 get_net_track(net, &sk->ns_tracker, priority);
2308 sock_inuse_add(net, 1);
2309 } else {
2310 net_passive_inc(net);
2311 __netns_tracker_alloc(net, &sk->ns_tracker,
2312 false, priority);
2313 }
2314
2315 sock_net_set(sk, net);
2316 refcount_set(&sk->sk_wmem_alloc, 1);
2317
2318 mem_cgroup_sk_alloc(sk);
2319 cgroup_sk_alloc(&sk->sk_cgrp_data);
2320 sock_update_classid(&sk->sk_cgrp_data);
2321 sock_update_netprioidx(&sk->sk_cgrp_data);
2322 sk_tx_queue_clear(sk);
2323 }
2324
2325 return sk;
2326 }
2327 EXPORT_SYMBOL(sk_alloc);
2328
2329 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2330 * grace period. This is the case for UDP sockets and TCP listeners.
2331 */
__sk_destruct(struct rcu_head * head)2332 static void __sk_destruct(struct rcu_head *head)
2333 {
2334 struct sock *sk = container_of(head, struct sock, sk_rcu);
2335 struct net *net = sock_net(sk);
2336 struct sk_filter *filter;
2337
2338 if (sk->sk_destruct)
2339 sk->sk_destruct(sk);
2340
2341 filter = rcu_dereference_check(sk->sk_filter,
2342 refcount_read(&sk->sk_wmem_alloc) == 0);
2343 if (filter) {
2344 sk_filter_uncharge(sk, filter);
2345 RCU_INIT_POINTER(sk->sk_filter, NULL);
2346 }
2347
2348 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2349
2350 #ifdef CONFIG_BPF_SYSCALL
2351 bpf_sk_storage_free(sk);
2352 #endif
2353
2354 if (atomic_read(&sk->sk_omem_alloc))
2355 pr_debug("%s: optmem leakage (%d bytes) detected\n",
2356 __func__, atomic_read(&sk->sk_omem_alloc));
2357
2358 if (sk->sk_frag.page) {
2359 put_page(sk->sk_frag.page);
2360 sk->sk_frag.page = NULL;
2361 }
2362
2363 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2364 put_cred(sk->sk_peer_cred);
2365 put_pid(sk->sk_peer_pid);
2366
2367 if (likely(sk->sk_net_refcnt)) {
2368 put_net_track(net, &sk->ns_tracker);
2369 } else {
2370 __netns_tracker_free(net, &sk->ns_tracker, false);
2371 net_passive_dec(net);
2372 }
2373 sk_prot_free(sk->sk_prot_creator, sk);
2374 }
2375
sk_net_refcnt_upgrade(struct sock * sk)2376 void sk_net_refcnt_upgrade(struct sock *sk)
2377 {
2378 struct net *net = sock_net(sk);
2379
2380 WARN_ON_ONCE(sk->sk_net_refcnt);
2381 __netns_tracker_free(net, &sk->ns_tracker, false);
2382 net_passive_dec(net);
2383 sk->sk_net_refcnt = 1;
2384 get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2385 sock_inuse_add(net, 1);
2386 }
2387 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2388
sk_destruct(struct sock * sk)2389 void sk_destruct(struct sock *sk)
2390 {
2391 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2392
2393 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2394 reuseport_detach_sock(sk);
2395 use_call_rcu = true;
2396 }
2397
2398 if (use_call_rcu)
2399 call_rcu(&sk->sk_rcu, __sk_destruct);
2400 else
2401 __sk_destruct(&sk->sk_rcu);
2402 }
2403
__sk_free(struct sock * sk)2404 static void __sk_free(struct sock *sk)
2405 {
2406 if (likely(sk->sk_net_refcnt))
2407 sock_inuse_add(sock_net(sk), -1);
2408
2409 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2410 sock_diag_broadcast_destroy(sk);
2411 else
2412 sk_destruct(sk);
2413 }
2414
sk_free(struct sock * sk)2415 void sk_free(struct sock *sk)
2416 {
2417 /*
2418 * We subtract one from sk_wmem_alloc and can know if
2419 * some packets are still in some tx queue.
2420 * If not null, sock_wfree() will call __sk_free(sk) later
2421 */
2422 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2423 __sk_free(sk);
2424 }
2425 EXPORT_SYMBOL(sk_free);
2426
sk_init_common(struct sock * sk)2427 static void sk_init_common(struct sock *sk)
2428 {
2429 skb_queue_head_init(&sk->sk_receive_queue);
2430 skb_queue_head_init(&sk->sk_write_queue);
2431 skb_queue_head_init(&sk->sk_error_queue);
2432
2433 rwlock_init(&sk->sk_callback_lock);
2434 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2435 af_rlock_keys + sk->sk_family,
2436 af_family_rlock_key_strings[sk->sk_family]);
2437 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2438 af_wlock_keys + sk->sk_family,
2439 af_family_wlock_key_strings[sk->sk_family]);
2440 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2441 af_elock_keys + sk->sk_family,
2442 af_family_elock_key_strings[sk->sk_family]);
2443 if (sk->sk_kern_sock)
2444 lockdep_set_class_and_name(&sk->sk_callback_lock,
2445 af_kern_callback_keys + sk->sk_family,
2446 af_family_kern_clock_key_strings[sk->sk_family]);
2447 else
2448 lockdep_set_class_and_name(&sk->sk_callback_lock,
2449 af_callback_keys + sk->sk_family,
2450 af_family_clock_key_strings[sk->sk_family]);
2451 }
2452
2453 /**
2454 * sk_clone_lock - clone a socket, and lock its clone
2455 * @sk: the socket to clone
2456 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2457 *
2458 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2459 */
sk_clone_lock(const struct sock * sk,const gfp_t priority)2460 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2461 {
2462 struct proto *prot = READ_ONCE(sk->sk_prot);
2463 struct sk_filter *filter;
2464 bool is_charged = true;
2465 struct sock *newsk;
2466
2467 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2468 if (!newsk)
2469 goto out;
2470
2471 sock_copy(newsk, sk);
2472
2473 newsk->sk_prot_creator = prot;
2474
2475 /* SANITY */
2476 if (likely(newsk->sk_net_refcnt)) {
2477 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2478 sock_inuse_add(sock_net(newsk), 1);
2479 } else {
2480 /* Kernel sockets are not elevating the struct net refcount.
2481 * Instead, use a tracker to more easily detect if a layer
2482 * is not properly dismantling its kernel sockets at netns
2483 * destroy time.
2484 */
2485 net_passive_inc(sock_net(newsk));
2486 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2487 false, priority);
2488 }
2489 sk_node_init(&newsk->sk_node);
2490 sock_lock_init(newsk);
2491 bh_lock_sock(newsk);
2492 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
2493 newsk->sk_backlog.len = 0;
2494
2495 atomic_set(&newsk->sk_rmem_alloc, 0);
2496
2497 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2498 refcount_set(&newsk->sk_wmem_alloc, 1);
2499
2500 atomic_set(&newsk->sk_omem_alloc, 0);
2501 sk_init_common(newsk);
2502
2503 newsk->sk_dst_cache = NULL;
2504 newsk->sk_dst_pending_confirm = 0;
2505 newsk->sk_wmem_queued = 0;
2506 newsk->sk_forward_alloc = 0;
2507 newsk->sk_reserved_mem = 0;
2508 atomic_set(&newsk->sk_drops, 0);
2509 newsk->sk_send_head = NULL;
2510 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2511 atomic_set(&newsk->sk_zckey, 0);
2512
2513 sock_reset_flag(newsk, SOCK_DONE);
2514
2515 /* sk->sk_memcg will be populated at accept() time */
2516 newsk->sk_memcg = NULL;
2517
2518 cgroup_sk_clone(&newsk->sk_cgrp_data);
2519
2520 rcu_read_lock();
2521 filter = rcu_dereference(sk->sk_filter);
2522 if (filter != NULL)
2523 /* though it's an empty new sock, the charging may fail
2524 * if sysctl_optmem_max was changed between creation of
2525 * original socket and cloning
2526 */
2527 is_charged = sk_filter_charge(newsk, filter);
2528 RCU_INIT_POINTER(newsk->sk_filter, filter);
2529 rcu_read_unlock();
2530
2531 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2532 /* We need to make sure that we don't uncharge the new
2533 * socket if we couldn't charge it in the first place
2534 * as otherwise we uncharge the parent's filter.
2535 */
2536 if (!is_charged)
2537 RCU_INIT_POINTER(newsk->sk_filter, NULL);
2538
2539 goto free;
2540 }
2541
2542 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2543
2544 if (bpf_sk_storage_clone(sk, newsk))
2545 goto free;
2546
2547 /* Clear sk_user_data if parent had the pointer tagged
2548 * as not suitable for copying when cloning.
2549 */
2550 if (sk_user_data_is_nocopy(newsk))
2551 newsk->sk_user_data = NULL;
2552
2553 newsk->sk_err = 0;
2554 newsk->sk_err_soft = 0;
2555 newsk->sk_priority = 0;
2556 newsk->sk_incoming_cpu = raw_smp_processor_id();
2557
2558 /* Before updating sk_refcnt, we must commit prior changes to memory
2559 * (Documentation/RCU/rculist_nulls.rst for details)
2560 */
2561 smp_wmb();
2562 refcount_set(&newsk->sk_refcnt, 2);
2563
2564 sk_set_socket(newsk, NULL);
2565 sk_tx_queue_clear(newsk);
2566 RCU_INIT_POINTER(newsk->sk_wq, NULL);
2567
2568 if (newsk->sk_prot->sockets_allocated)
2569 sk_sockets_allocated_inc(newsk);
2570
2571 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2572 net_enable_timestamp();
2573 out:
2574 return newsk;
2575 free:
2576 /* It is still raw copy of parent, so invalidate
2577 * destructor and make plain sk_free()
2578 */
2579 newsk->sk_destruct = NULL;
2580 bh_unlock_sock(newsk);
2581 sk_free(newsk);
2582 newsk = NULL;
2583 goto out;
2584 }
2585 EXPORT_SYMBOL_GPL(sk_clone_lock);
2586
sk_dst_gso_max_size(struct sock * sk,struct dst_entry * dst)2587 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2588 {
2589 bool is_ipv6 = false;
2590 u32 max_size;
2591
2592 #if IS_ENABLED(CONFIG_IPV6)
2593 is_ipv6 = (sk->sk_family == AF_INET6 &&
2594 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2595 #endif
2596 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2597 max_size = is_ipv6 ? READ_ONCE(dst_dev(dst)->gso_max_size) :
2598 READ_ONCE(dst_dev(dst)->gso_ipv4_max_size);
2599 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2600 max_size = GSO_LEGACY_MAX_SIZE;
2601
2602 return max_size - (MAX_TCP_HEADER + 1);
2603 }
2604
sk_setup_caps(struct sock * sk,struct dst_entry * dst)2605 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2606 {
2607 u32 max_segs = 1;
2608
2609 sk->sk_route_caps = dst_dev(dst)->features;
2610 if (sk_is_tcp(sk)) {
2611 struct inet_connection_sock *icsk = inet_csk(sk);
2612
2613 sk->sk_route_caps |= NETIF_F_GSO;
2614 icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2615 }
2616 if (sk->sk_route_caps & NETIF_F_GSO)
2617 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2618 if (unlikely(sk->sk_gso_disabled))
2619 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2620 if (sk_can_gso(sk)) {
2621 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2622 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2623 } else {
2624 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2625 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2626 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2627 max_segs = max_t(u32, READ_ONCE(dst_dev(dst)->gso_max_segs), 1);
2628 }
2629 }
2630 sk->sk_gso_max_segs = max_segs;
2631 sk_dst_set(sk, dst);
2632 }
2633 EXPORT_SYMBOL_GPL(sk_setup_caps);
2634
2635 /*
2636 * Simple resource managers for sockets.
2637 */
2638
2639
2640 /*
2641 * Write buffer destructor automatically called from kfree_skb.
2642 */
sock_wfree(struct sk_buff * skb)2643 void sock_wfree(struct sk_buff *skb)
2644 {
2645 struct sock *sk = skb->sk;
2646 unsigned int len = skb->truesize;
2647 bool free;
2648
2649 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2650 if (sock_flag(sk, SOCK_RCU_FREE) &&
2651 sk->sk_write_space == sock_def_write_space) {
2652 rcu_read_lock();
2653 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2654 sock_def_write_space_wfree(sk);
2655 rcu_read_unlock();
2656 if (unlikely(free))
2657 __sk_free(sk);
2658 return;
2659 }
2660
2661 /*
2662 * Keep a reference on sk_wmem_alloc, this will be released
2663 * after sk_write_space() call
2664 */
2665 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2666 sk->sk_write_space(sk);
2667 len = 1;
2668 }
2669 /*
2670 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2671 * could not do because of in-flight packets
2672 */
2673 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2674 __sk_free(sk);
2675 }
2676 EXPORT_SYMBOL(sock_wfree);
2677
2678 /* This variant of sock_wfree() is used by TCP,
2679 * since it sets SOCK_USE_WRITE_QUEUE.
2680 */
__sock_wfree(struct sk_buff * skb)2681 void __sock_wfree(struct sk_buff *skb)
2682 {
2683 struct sock *sk = skb->sk;
2684
2685 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2686 __sk_free(sk);
2687 }
2688
skb_set_owner_w(struct sk_buff * skb,struct sock * sk)2689 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2690 {
2691 skb_orphan(skb);
2692 #ifdef CONFIG_INET
2693 if (unlikely(!sk_fullsock(sk)))
2694 return skb_set_owner_edemux(skb, sk);
2695 #endif
2696 skb->sk = sk;
2697 skb->destructor = sock_wfree;
2698 skb_set_hash_from_sk(skb, sk);
2699 /*
2700 * We used to take a refcount on sk, but following operation
2701 * is enough to guarantee sk_free() won't free this sock until
2702 * all in-flight packets are completed
2703 */
2704 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2705 }
2706 EXPORT_SYMBOL(skb_set_owner_w);
2707
can_skb_orphan_partial(const struct sk_buff * skb)2708 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2709 {
2710 /* Drivers depend on in-order delivery for crypto offload,
2711 * partial orphan breaks out-of-order-OK logic.
2712 */
2713 if (skb_is_decrypted(skb))
2714 return false;
2715
2716 return (skb->destructor == sock_wfree ||
2717 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2718 }
2719
2720 /* This helper is used by netem, as it can hold packets in its
2721 * delay queue. We want to allow the owner socket to send more
2722 * packets, as if they were already TX completed by a typical driver.
2723 * But we also want to keep skb->sk set because some packet schedulers
2724 * rely on it (sch_fq for example).
2725 */
skb_orphan_partial(struct sk_buff * skb)2726 void skb_orphan_partial(struct sk_buff *skb)
2727 {
2728 if (skb_is_tcp_pure_ack(skb))
2729 return;
2730
2731 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2732 return;
2733
2734 skb_orphan(skb);
2735 }
2736 EXPORT_SYMBOL(skb_orphan_partial);
2737
2738 /*
2739 * Read buffer destructor automatically called from kfree_skb.
2740 */
sock_rfree(struct sk_buff * skb)2741 void sock_rfree(struct sk_buff *skb)
2742 {
2743 struct sock *sk = skb->sk;
2744 unsigned int len = skb->truesize;
2745
2746 atomic_sub(len, &sk->sk_rmem_alloc);
2747 sk_mem_uncharge(sk, len);
2748 }
2749 EXPORT_SYMBOL(sock_rfree);
2750
2751 /*
2752 * Buffer destructor for skbs that are not used directly in read or write
2753 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2754 */
sock_efree(struct sk_buff * skb)2755 void sock_efree(struct sk_buff *skb)
2756 {
2757 sock_put(skb->sk);
2758 }
2759 EXPORT_SYMBOL(sock_efree);
2760
2761 /* Buffer destructor for prefetch/receive path where reference count may
2762 * not be held, e.g. for listen sockets.
2763 */
2764 #ifdef CONFIG_INET
sock_pfree(struct sk_buff * skb)2765 void sock_pfree(struct sk_buff *skb)
2766 {
2767 struct sock *sk = skb->sk;
2768
2769 if (!sk_is_refcounted(sk))
2770 return;
2771
2772 if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2773 inet_reqsk(sk)->rsk_listener = NULL;
2774 reqsk_free(inet_reqsk(sk));
2775 return;
2776 }
2777
2778 sock_gen_put(sk);
2779 }
2780 EXPORT_SYMBOL(sock_pfree);
2781 #endif /* CONFIG_INET */
2782
2783 /*
2784 * Allocate a skb from the socket's send buffer.
2785 */
sock_wmalloc(struct sock * sk,unsigned long size,int force,gfp_t priority)2786 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2787 gfp_t priority)
2788 {
2789 if (force ||
2790 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2791 struct sk_buff *skb = alloc_skb(size, priority);
2792
2793 if (skb) {
2794 skb_set_owner_w(skb, sk);
2795 return skb;
2796 }
2797 }
2798 return NULL;
2799 }
2800 EXPORT_SYMBOL(sock_wmalloc);
2801
sock_ofree(struct sk_buff * skb)2802 static void sock_ofree(struct sk_buff *skb)
2803 {
2804 struct sock *sk = skb->sk;
2805
2806 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2807 }
2808
sock_omalloc(struct sock * sk,unsigned long size,gfp_t priority)2809 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2810 gfp_t priority)
2811 {
2812 struct sk_buff *skb;
2813
2814 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2815 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2816 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2817 return NULL;
2818
2819 skb = alloc_skb(size, priority);
2820 if (!skb)
2821 return NULL;
2822
2823 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2824 skb->sk = sk;
2825 skb->destructor = sock_ofree;
2826 return skb;
2827 }
2828
2829 /*
2830 * Allocate a memory block from the socket's option memory buffer.
2831 */
sock_kmalloc(struct sock * sk,int size,gfp_t priority)2832 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2833 {
2834 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2835
2836 if ((unsigned int)size <= optmem_max &&
2837 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2838 void *mem;
2839 /* First do the add, to avoid the race if kmalloc
2840 * might sleep.
2841 */
2842 atomic_add(size, &sk->sk_omem_alloc);
2843 mem = kmalloc(size, priority);
2844 if (mem)
2845 return mem;
2846 atomic_sub(size, &sk->sk_omem_alloc);
2847 }
2848 return NULL;
2849 }
2850 EXPORT_SYMBOL(sock_kmalloc);
2851
2852 /*
2853 * Duplicate the input "src" memory block using the socket's
2854 * option memory buffer.
2855 */
sock_kmemdup(struct sock * sk,const void * src,int size,gfp_t priority)2856 void *sock_kmemdup(struct sock *sk, const void *src,
2857 int size, gfp_t priority)
2858 {
2859 void *mem;
2860
2861 mem = sock_kmalloc(sk, size, priority);
2862 if (mem)
2863 memcpy(mem, src, size);
2864 return mem;
2865 }
2866 EXPORT_SYMBOL(sock_kmemdup);
2867
2868 /* Free an option memory block. Note, we actually want the inline
2869 * here as this allows gcc to detect the nullify and fold away the
2870 * condition entirely.
2871 */
__sock_kfree_s(struct sock * sk,void * mem,int size,const bool nullify)2872 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2873 const bool nullify)
2874 {
2875 if (WARN_ON_ONCE(!mem))
2876 return;
2877 if (nullify)
2878 kfree_sensitive(mem);
2879 else
2880 kfree(mem);
2881 atomic_sub(size, &sk->sk_omem_alloc);
2882 }
2883
sock_kfree_s(struct sock * sk,void * mem,int size)2884 void sock_kfree_s(struct sock *sk, void *mem, int size)
2885 {
2886 __sock_kfree_s(sk, mem, size, false);
2887 }
2888 EXPORT_SYMBOL(sock_kfree_s);
2889
sock_kzfree_s(struct sock * sk,void * mem,int size)2890 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2891 {
2892 __sock_kfree_s(sk, mem, size, true);
2893 }
2894 EXPORT_SYMBOL(sock_kzfree_s);
2895
2896 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2897 I think, these locks should be removed for datagram sockets.
2898 */
sock_wait_for_wmem(struct sock * sk,long timeo)2899 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2900 {
2901 DEFINE_WAIT(wait);
2902
2903 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2904 for (;;) {
2905 if (!timeo)
2906 break;
2907 if (signal_pending(current))
2908 break;
2909 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2910 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2911 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2912 break;
2913 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2914 break;
2915 if (READ_ONCE(sk->sk_err))
2916 break;
2917 timeo = schedule_timeout(timeo);
2918 }
2919 finish_wait(sk_sleep(sk), &wait);
2920 return timeo;
2921 }
2922
2923
2924 /*
2925 * Generic send/receive buffer handlers
2926 */
2927
sock_alloc_send_pskb(struct sock * sk,unsigned long header_len,unsigned long data_len,int noblock,int * errcode,int max_page_order)2928 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2929 unsigned long data_len, int noblock,
2930 int *errcode, int max_page_order)
2931 {
2932 struct sk_buff *skb;
2933 long timeo;
2934 int err;
2935
2936 timeo = sock_sndtimeo(sk, noblock);
2937 for (;;) {
2938 err = sock_error(sk);
2939 if (err != 0)
2940 goto failure;
2941
2942 err = -EPIPE;
2943 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2944 goto failure;
2945
2946 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2947 break;
2948
2949 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2950 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2951 err = -EAGAIN;
2952 if (!timeo)
2953 goto failure;
2954 if (signal_pending(current))
2955 goto interrupted;
2956 timeo = sock_wait_for_wmem(sk, timeo);
2957 }
2958 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2959 errcode, sk->sk_allocation);
2960 if (skb)
2961 skb_set_owner_w(skb, sk);
2962 return skb;
2963
2964 interrupted:
2965 err = sock_intr_errno(timeo);
2966 failure:
2967 *errcode = err;
2968 return NULL;
2969 }
2970 EXPORT_SYMBOL(sock_alloc_send_pskb);
2971
__sock_cmsg_send(struct sock * sk,struct cmsghdr * cmsg,struct sockcm_cookie * sockc)2972 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2973 struct sockcm_cookie *sockc)
2974 {
2975 u32 tsflags;
2976
2977 BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
2978
2979 switch (cmsg->cmsg_type) {
2980 case SO_MARK:
2981 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2982 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2983 return -EPERM;
2984 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2985 return -EINVAL;
2986 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2987 break;
2988 case SO_TIMESTAMPING_OLD:
2989 case SO_TIMESTAMPING_NEW:
2990 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2991 return -EINVAL;
2992
2993 tsflags = *(u32 *)CMSG_DATA(cmsg);
2994 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2995 return -EINVAL;
2996
2997 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2998 sockc->tsflags |= tsflags;
2999 break;
3000 case SCM_TXTIME:
3001 if (!sock_flag(sk, SOCK_TXTIME))
3002 return -EINVAL;
3003 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3004 return -EINVAL;
3005 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
3006 break;
3007 case SCM_TS_OPT_ID:
3008 if (sk_is_tcp(sk))
3009 return -EINVAL;
3010 tsflags = READ_ONCE(sk->sk_tsflags);
3011 if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3012 return -EINVAL;
3013 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3014 return -EINVAL;
3015 sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3016 sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3017 break;
3018 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3019 case SCM_RIGHTS:
3020 case SCM_CREDENTIALS:
3021 break;
3022 case SO_PRIORITY:
3023 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3024 return -EINVAL;
3025 if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3026 return -EPERM;
3027 sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3028 break;
3029 case SCM_DEVMEM_DMABUF:
3030 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3031 return -EINVAL;
3032 sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3033 break;
3034 default:
3035 return -EINVAL;
3036 }
3037 return 0;
3038 }
3039 EXPORT_SYMBOL(__sock_cmsg_send);
3040
sock_cmsg_send(struct sock * sk,struct msghdr * msg,struct sockcm_cookie * sockc)3041 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3042 struct sockcm_cookie *sockc)
3043 {
3044 struct cmsghdr *cmsg;
3045 int ret;
3046
3047 for_each_cmsghdr(cmsg, msg) {
3048 if (!CMSG_OK(msg, cmsg))
3049 return -EINVAL;
3050 if (cmsg->cmsg_level != SOL_SOCKET)
3051 continue;
3052 ret = __sock_cmsg_send(sk, cmsg, sockc);
3053 if (ret)
3054 return ret;
3055 }
3056 return 0;
3057 }
3058 EXPORT_SYMBOL(sock_cmsg_send);
3059
sk_enter_memory_pressure(struct sock * sk)3060 static void sk_enter_memory_pressure(struct sock *sk)
3061 {
3062 if (!sk->sk_prot->enter_memory_pressure)
3063 return;
3064
3065 sk->sk_prot->enter_memory_pressure(sk);
3066 }
3067
sk_leave_memory_pressure(struct sock * sk)3068 static void sk_leave_memory_pressure(struct sock *sk)
3069 {
3070 if (sk->sk_prot->leave_memory_pressure) {
3071 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3072 tcp_leave_memory_pressure, sk);
3073 } else {
3074 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3075
3076 if (memory_pressure && READ_ONCE(*memory_pressure))
3077 WRITE_ONCE(*memory_pressure, 0);
3078 }
3079 }
3080
3081 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3082
3083 /**
3084 * skb_page_frag_refill - check that a page_frag contains enough room
3085 * @sz: minimum size of the fragment we want to get
3086 * @pfrag: pointer to page_frag
3087 * @gfp: priority for memory allocation
3088 *
3089 * Note: While this allocator tries to use high order pages, there is
3090 * no guarantee that allocations succeed. Therefore, @sz MUST be
3091 * less or equal than PAGE_SIZE.
3092 */
skb_page_frag_refill(unsigned int sz,struct page_frag * pfrag,gfp_t gfp)3093 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3094 {
3095 if (pfrag->page) {
3096 if (page_ref_count(pfrag->page) == 1) {
3097 pfrag->offset = 0;
3098 return true;
3099 }
3100 if (pfrag->offset + sz <= pfrag->size)
3101 return true;
3102 put_page(pfrag->page);
3103 }
3104
3105 pfrag->offset = 0;
3106 if (SKB_FRAG_PAGE_ORDER &&
3107 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3108 /* Avoid direct reclaim but allow kswapd to wake */
3109 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3110 __GFP_COMP | __GFP_NOWARN |
3111 __GFP_NORETRY,
3112 SKB_FRAG_PAGE_ORDER);
3113 if (likely(pfrag->page)) {
3114 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3115 return true;
3116 }
3117 }
3118 pfrag->page = alloc_page(gfp);
3119 if (likely(pfrag->page)) {
3120 pfrag->size = PAGE_SIZE;
3121 return true;
3122 }
3123 return false;
3124 }
3125 EXPORT_SYMBOL(skb_page_frag_refill);
3126
sk_page_frag_refill(struct sock * sk,struct page_frag * pfrag)3127 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3128 {
3129 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3130 return true;
3131
3132 sk_enter_memory_pressure(sk);
3133 sk_stream_moderate_sndbuf(sk);
3134 return false;
3135 }
3136 EXPORT_SYMBOL(sk_page_frag_refill);
3137
__lock_sock(struct sock * sk)3138 void __lock_sock(struct sock *sk)
3139 __releases(&sk->sk_lock.slock)
3140 __acquires(&sk->sk_lock.slock)
3141 {
3142 DEFINE_WAIT(wait);
3143
3144 for (;;) {
3145 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3146 TASK_UNINTERRUPTIBLE);
3147 spin_unlock_bh(&sk->sk_lock.slock);
3148 schedule();
3149 spin_lock_bh(&sk->sk_lock.slock);
3150 if (!sock_owned_by_user(sk))
3151 break;
3152 }
3153 finish_wait(&sk->sk_lock.wq, &wait);
3154 }
3155
__release_sock(struct sock * sk)3156 void __release_sock(struct sock *sk)
3157 __releases(&sk->sk_lock.slock)
3158 __acquires(&sk->sk_lock.slock)
3159 {
3160 struct sk_buff *skb, *next;
3161
3162 while ((skb = sk->sk_backlog.head) != NULL) {
3163 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3164
3165 spin_unlock_bh(&sk->sk_lock.slock);
3166
3167 do {
3168 next = skb->next;
3169 prefetch(next);
3170 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3171 skb_mark_not_on_list(skb);
3172 sk_backlog_rcv(sk, skb);
3173
3174 cond_resched();
3175
3176 skb = next;
3177 } while (skb != NULL);
3178
3179 spin_lock_bh(&sk->sk_lock.slock);
3180 }
3181
3182 /*
3183 * Doing the zeroing here guarantee we can not loop forever
3184 * while a wild producer attempts to flood us.
3185 */
3186 sk->sk_backlog.len = 0;
3187 }
3188
__sk_flush_backlog(struct sock * sk)3189 void __sk_flush_backlog(struct sock *sk)
3190 {
3191 spin_lock_bh(&sk->sk_lock.slock);
3192 __release_sock(sk);
3193
3194 if (sk->sk_prot->release_cb)
3195 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3196 tcp_release_cb, sk);
3197
3198 spin_unlock_bh(&sk->sk_lock.slock);
3199 }
3200 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3201
3202 /**
3203 * sk_wait_data - wait for data to arrive at sk_receive_queue
3204 * @sk: sock to wait on
3205 * @timeo: for how long
3206 * @skb: last skb seen on sk_receive_queue
3207 *
3208 * Now socket state including sk->sk_err is changed only under lock,
3209 * hence we may omit checks after joining wait queue.
3210 * We check receive queue before schedule() only as optimization;
3211 * it is very likely that release_sock() added new data.
3212 */
sk_wait_data(struct sock * sk,long * timeo,const struct sk_buff * skb)3213 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3214 {
3215 DEFINE_WAIT_FUNC(wait, woken_wake_function);
3216 int rc;
3217
3218 add_wait_queue(sk_sleep(sk), &wait);
3219 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3220 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3221 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3222 remove_wait_queue(sk_sleep(sk), &wait);
3223 return rc;
3224 }
3225 EXPORT_SYMBOL(sk_wait_data);
3226
3227 /**
3228 * __sk_mem_raise_allocated - increase memory_allocated
3229 * @sk: socket
3230 * @size: memory size to allocate
3231 * @amt: pages to allocate
3232 * @kind: allocation type
3233 *
3234 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3235 *
3236 * Unlike the globally shared limits among the sockets under same protocol,
3237 * consuming the budget of a memcg won't have direct effect on other ones.
3238 * So be optimistic about memcg's tolerance, and leave the callers to decide
3239 * whether or not to raise allocated through sk_under_memory_pressure() or
3240 * its variants.
3241 */
__sk_mem_raise_allocated(struct sock * sk,int size,int amt,int kind)3242 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3243 {
3244 struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3245 struct proto *prot = sk->sk_prot;
3246 bool charged = true;
3247 long allocated;
3248
3249 sk_memory_allocated_add(sk, amt);
3250 allocated = sk_memory_allocated(sk);
3251
3252 if (memcg) {
3253 charged = mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge());
3254 if (!charged)
3255 goto suppress_allocation;
3256 }
3257
3258 /* Under limit. */
3259 if (allocated <= sk_prot_mem_limits(sk, 0)) {
3260 sk_leave_memory_pressure(sk);
3261 return 1;
3262 }
3263
3264 /* Under pressure. */
3265 if (allocated > sk_prot_mem_limits(sk, 1))
3266 sk_enter_memory_pressure(sk);
3267
3268 /* Over hard limit. */
3269 if (allocated > sk_prot_mem_limits(sk, 2))
3270 goto suppress_allocation;
3271
3272 /* Guarantee minimum buffer size under pressure (either global
3273 * or memcg) to make sure features described in RFC 7323 (TCP
3274 * Extensions for High Performance) work properly.
3275 *
3276 * This rule does NOT stand when exceeds global or memcg's hard
3277 * limit, or else a DoS attack can be taken place by spawning
3278 * lots of sockets whose usage are under minimum buffer size.
3279 */
3280 if (kind == SK_MEM_RECV) {
3281 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3282 return 1;
3283
3284 } else { /* SK_MEM_SEND */
3285 int wmem0 = sk_get_wmem0(sk, prot);
3286
3287 if (sk->sk_type == SOCK_STREAM) {
3288 if (sk->sk_wmem_queued < wmem0)
3289 return 1;
3290 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3291 return 1;
3292 }
3293 }
3294
3295 if (sk_has_memory_pressure(sk)) {
3296 u64 alloc;
3297
3298 /* The following 'average' heuristic is within the
3299 * scope of global accounting, so it only makes
3300 * sense for global memory pressure.
3301 */
3302 if (!sk_under_global_memory_pressure(sk))
3303 return 1;
3304
3305 /* Try to be fair among all the sockets under global
3306 * pressure by allowing the ones that below average
3307 * usage to raise.
3308 */
3309 alloc = sk_sockets_allocated_read_positive(sk);
3310 if (sk_prot_mem_limits(sk, 2) > alloc *
3311 sk_mem_pages(sk->sk_wmem_queued +
3312 atomic_read(&sk->sk_rmem_alloc) +
3313 sk->sk_forward_alloc))
3314 return 1;
3315 }
3316
3317 suppress_allocation:
3318
3319 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3320 sk_stream_moderate_sndbuf(sk);
3321
3322 /* Fail only if socket is _under_ its sndbuf.
3323 * In this case we cannot block, so that we have to fail.
3324 */
3325 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3326 /* Force charge with __GFP_NOFAIL */
3327 if (memcg && !charged) {
3328 mem_cgroup_charge_skmem(memcg, amt,
3329 gfp_memcg_charge() | __GFP_NOFAIL);
3330 }
3331 return 1;
3332 }
3333 }
3334
3335 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3336 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3337
3338 sk_memory_allocated_sub(sk, amt);
3339
3340 if (memcg && charged)
3341 mem_cgroup_uncharge_skmem(memcg, amt);
3342
3343 return 0;
3344 }
3345
3346 /**
3347 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3348 * @sk: socket
3349 * @size: memory size to allocate
3350 * @kind: allocation type
3351 *
3352 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3353 * rmem allocation. This function assumes that protocols which have
3354 * memory_pressure use sk_wmem_queued as write buffer accounting.
3355 */
__sk_mem_schedule(struct sock * sk,int size,int kind)3356 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3357 {
3358 int ret, amt = sk_mem_pages(size);
3359
3360 sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3361 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3362 if (!ret)
3363 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3364 return ret;
3365 }
3366 EXPORT_SYMBOL(__sk_mem_schedule);
3367
3368 /**
3369 * __sk_mem_reduce_allocated - reclaim memory_allocated
3370 * @sk: socket
3371 * @amount: number of quanta
3372 *
3373 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3374 */
__sk_mem_reduce_allocated(struct sock * sk,int amount)3375 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3376 {
3377 sk_memory_allocated_sub(sk, amount);
3378
3379 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3380 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3381
3382 if (sk_under_global_memory_pressure(sk) &&
3383 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3384 sk_leave_memory_pressure(sk);
3385 }
3386
3387 /**
3388 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3389 * @sk: socket
3390 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3391 */
__sk_mem_reclaim(struct sock * sk,int amount)3392 void __sk_mem_reclaim(struct sock *sk, int amount)
3393 {
3394 amount >>= PAGE_SHIFT;
3395 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3396 __sk_mem_reduce_allocated(sk, amount);
3397 }
3398 EXPORT_SYMBOL(__sk_mem_reclaim);
3399
sk_set_peek_off(struct sock * sk,int val)3400 int sk_set_peek_off(struct sock *sk, int val)
3401 {
3402 WRITE_ONCE(sk->sk_peek_off, val);
3403 return 0;
3404 }
3405 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3406
3407 /*
3408 * Set of default routines for initialising struct proto_ops when
3409 * the protocol does not support a particular function. In certain
3410 * cases where it makes no sense for a protocol to have a "do nothing"
3411 * function, some default processing is provided.
3412 */
3413
sock_no_bind(struct socket * sock,struct sockaddr * saddr,int len)3414 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3415 {
3416 return -EOPNOTSUPP;
3417 }
3418 EXPORT_SYMBOL(sock_no_bind);
3419
sock_no_connect(struct socket * sock,struct sockaddr * saddr,int len,int flags)3420 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3421 int len, int flags)
3422 {
3423 return -EOPNOTSUPP;
3424 }
3425 EXPORT_SYMBOL(sock_no_connect);
3426
sock_no_socketpair(struct socket * sock1,struct socket * sock2)3427 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3428 {
3429 return -EOPNOTSUPP;
3430 }
3431 EXPORT_SYMBOL(sock_no_socketpair);
3432
sock_no_accept(struct socket * sock,struct socket * newsock,struct proto_accept_arg * arg)3433 int sock_no_accept(struct socket *sock, struct socket *newsock,
3434 struct proto_accept_arg *arg)
3435 {
3436 return -EOPNOTSUPP;
3437 }
3438 EXPORT_SYMBOL(sock_no_accept);
3439
sock_no_getname(struct socket * sock,struct sockaddr * saddr,int peer)3440 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3441 int peer)
3442 {
3443 return -EOPNOTSUPP;
3444 }
3445 EXPORT_SYMBOL(sock_no_getname);
3446
sock_no_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)3447 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3448 {
3449 return -EOPNOTSUPP;
3450 }
3451 EXPORT_SYMBOL(sock_no_ioctl);
3452
sock_no_listen(struct socket * sock,int backlog)3453 int sock_no_listen(struct socket *sock, int backlog)
3454 {
3455 return -EOPNOTSUPP;
3456 }
3457 EXPORT_SYMBOL(sock_no_listen);
3458
sock_no_shutdown(struct socket * sock,int how)3459 int sock_no_shutdown(struct socket *sock, int how)
3460 {
3461 return -EOPNOTSUPP;
3462 }
3463 EXPORT_SYMBOL(sock_no_shutdown);
3464
sock_no_sendmsg(struct socket * sock,struct msghdr * m,size_t len)3465 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3466 {
3467 return -EOPNOTSUPP;
3468 }
3469 EXPORT_SYMBOL(sock_no_sendmsg);
3470
sock_no_sendmsg_locked(struct sock * sk,struct msghdr * m,size_t len)3471 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3472 {
3473 return -EOPNOTSUPP;
3474 }
3475 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3476
sock_no_recvmsg(struct socket * sock,struct msghdr * m,size_t len,int flags)3477 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3478 int flags)
3479 {
3480 return -EOPNOTSUPP;
3481 }
3482 EXPORT_SYMBOL(sock_no_recvmsg);
3483
sock_no_mmap(struct file * file,struct socket * sock,struct vm_area_struct * vma)3484 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3485 {
3486 /* Mirror missing mmap method error code */
3487 return -ENODEV;
3488 }
3489 EXPORT_SYMBOL(sock_no_mmap);
3490
3491 /*
3492 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3493 * various sock-based usage counts.
3494 */
__receive_sock(struct file * file)3495 void __receive_sock(struct file *file)
3496 {
3497 struct socket *sock;
3498
3499 sock = sock_from_file(file);
3500 if (sock) {
3501 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3502 sock_update_classid(&sock->sk->sk_cgrp_data);
3503 }
3504 }
3505
3506 /*
3507 * Default Socket Callbacks
3508 */
3509
sock_def_wakeup(struct sock * sk)3510 static void sock_def_wakeup(struct sock *sk)
3511 {
3512 struct socket_wq *wq;
3513
3514 rcu_read_lock();
3515 wq = rcu_dereference(sk->sk_wq);
3516 if (skwq_has_sleeper(wq))
3517 wake_up_interruptible_all(&wq->wait);
3518 rcu_read_unlock();
3519 }
3520
sock_def_error_report(struct sock * sk)3521 static void sock_def_error_report(struct sock *sk)
3522 {
3523 struct socket_wq *wq;
3524
3525 rcu_read_lock();
3526 wq = rcu_dereference(sk->sk_wq);
3527 if (skwq_has_sleeper(wq))
3528 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3529 sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3530 rcu_read_unlock();
3531 }
3532
sock_def_readable(struct sock * sk)3533 void sock_def_readable(struct sock *sk)
3534 {
3535 struct socket_wq *wq;
3536
3537 trace_sk_data_ready(sk);
3538
3539 rcu_read_lock();
3540 wq = rcu_dereference(sk->sk_wq);
3541 if (skwq_has_sleeper(wq))
3542 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3543 EPOLLRDNORM | EPOLLRDBAND);
3544 sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3545 rcu_read_unlock();
3546 }
3547
sock_def_write_space(struct sock * sk)3548 static void sock_def_write_space(struct sock *sk)
3549 {
3550 struct socket_wq *wq;
3551
3552 rcu_read_lock();
3553
3554 /* Do not wake up a writer until he can make "significant"
3555 * progress. --DaveM
3556 */
3557 if (sock_writeable(sk)) {
3558 wq = rcu_dereference(sk->sk_wq);
3559 if (skwq_has_sleeper(wq))
3560 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3561 EPOLLWRNORM | EPOLLWRBAND);
3562
3563 /* Should agree with poll, otherwise some programs break */
3564 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3565 }
3566
3567 rcu_read_unlock();
3568 }
3569
3570 /* An optimised version of sock_def_write_space(), should only be called
3571 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3572 * ->sk_wmem_alloc.
3573 */
sock_def_write_space_wfree(struct sock * sk)3574 static void sock_def_write_space_wfree(struct sock *sk)
3575 {
3576 /* Do not wake up a writer until he can make "significant"
3577 * progress. --DaveM
3578 */
3579 if (sock_writeable(sk)) {
3580 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3581
3582 /* rely on refcount_sub from sock_wfree() */
3583 smp_mb__after_atomic();
3584 if (wq && waitqueue_active(&wq->wait))
3585 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3586 EPOLLWRNORM | EPOLLWRBAND);
3587
3588 /* Should agree with poll, otherwise some programs break */
3589 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3590 }
3591 }
3592
sock_def_destruct(struct sock * sk)3593 static void sock_def_destruct(struct sock *sk)
3594 {
3595 }
3596
sk_send_sigurg(struct sock * sk)3597 void sk_send_sigurg(struct sock *sk)
3598 {
3599 if (sk->sk_socket && sk->sk_socket->file)
3600 if (send_sigurg(sk->sk_socket->file))
3601 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3602 }
3603 EXPORT_SYMBOL(sk_send_sigurg);
3604
sk_reset_timer(struct sock * sk,struct timer_list * timer,unsigned long expires)3605 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3606 unsigned long expires)
3607 {
3608 if (!mod_timer(timer, expires))
3609 sock_hold(sk);
3610 }
3611 EXPORT_SYMBOL(sk_reset_timer);
3612
sk_stop_timer(struct sock * sk,struct timer_list * timer)3613 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3614 {
3615 if (timer_delete(timer))
3616 __sock_put(sk);
3617 }
3618 EXPORT_SYMBOL(sk_stop_timer);
3619
sk_stop_timer_sync(struct sock * sk,struct timer_list * timer)3620 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3621 {
3622 if (timer_delete_sync(timer))
3623 __sock_put(sk);
3624 }
3625 EXPORT_SYMBOL(sk_stop_timer_sync);
3626
sock_init_data_uid(struct socket * sock,struct sock * sk,kuid_t uid)3627 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3628 {
3629 sk_init_common(sk);
3630 sk->sk_send_head = NULL;
3631
3632 timer_setup(&sk->sk_timer, NULL, 0);
3633
3634 sk->sk_allocation = GFP_KERNEL;
3635 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default);
3636 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default);
3637 sk->sk_state = TCP_CLOSE;
3638 sk->sk_use_task_frag = true;
3639 sk_set_socket(sk, sock);
3640
3641 sock_set_flag(sk, SOCK_ZAPPED);
3642
3643 if (sock) {
3644 sk->sk_type = sock->type;
3645 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3646 sock->sk = sk;
3647 } else {
3648 RCU_INIT_POINTER(sk->sk_wq, NULL);
3649 }
3650 sk->sk_uid = uid;
3651
3652 sk->sk_state_change = sock_def_wakeup;
3653 sk->sk_data_ready = sock_def_readable;
3654 sk->sk_write_space = sock_def_write_space;
3655 sk->sk_error_report = sock_def_error_report;
3656 sk->sk_destruct = sock_def_destruct;
3657
3658 sk->sk_frag.page = NULL;
3659 sk->sk_frag.offset = 0;
3660 sk->sk_peek_off = -1;
3661
3662 sk->sk_peer_pid = NULL;
3663 sk->sk_peer_cred = NULL;
3664 spin_lock_init(&sk->sk_peer_lock);
3665
3666 sk->sk_write_pending = 0;
3667 sk->sk_rcvlowat = 1;
3668 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3669 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3670
3671 sk->sk_stamp = SK_DEFAULT_STAMP;
3672 #if BITS_PER_LONG==32
3673 seqlock_init(&sk->sk_stamp_seq);
3674 #endif
3675 atomic_set(&sk->sk_zckey, 0);
3676
3677 #ifdef CONFIG_NET_RX_BUSY_POLL
3678 sk->sk_napi_id = 0;
3679 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read);
3680 #endif
3681
3682 sk->sk_max_pacing_rate = ~0UL;
3683 sk->sk_pacing_rate = ~0UL;
3684 WRITE_ONCE(sk->sk_pacing_shift, 10);
3685 sk->sk_incoming_cpu = -1;
3686
3687 sk_rx_queue_clear(sk);
3688 /*
3689 * Before updating sk_refcnt, we must commit prior changes to memory
3690 * (Documentation/RCU/rculist_nulls.rst for details)
3691 */
3692 smp_wmb();
3693 refcount_set(&sk->sk_refcnt, 1);
3694 atomic_set(&sk->sk_drops, 0);
3695 }
3696 EXPORT_SYMBOL(sock_init_data_uid);
3697
sock_init_data(struct socket * sock,struct sock * sk)3698 void sock_init_data(struct socket *sock, struct sock *sk)
3699 {
3700 kuid_t uid = sock ?
3701 SOCK_INODE(sock)->i_uid :
3702 make_kuid(sock_net(sk)->user_ns, 0);
3703
3704 sock_init_data_uid(sock, sk, uid);
3705 }
3706 EXPORT_SYMBOL(sock_init_data);
3707
lock_sock_nested(struct sock * sk,int subclass)3708 void lock_sock_nested(struct sock *sk, int subclass)
3709 {
3710 /* The sk_lock has mutex_lock() semantics here. */
3711 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3712
3713 might_sleep();
3714 spin_lock_bh(&sk->sk_lock.slock);
3715 if (sock_owned_by_user_nocheck(sk))
3716 __lock_sock(sk);
3717 sk->sk_lock.owned = 1;
3718 spin_unlock_bh(&sk->sk_lock.slock);
3719 }
3720 EXPORT_SYMBOL(lock_sock_nested);
3721
release_sock(struct sock * sk)3722 void release_sock(struct sock *sk)
3723 {
3724 spin_lock_bh(&sk->sk_lock.slock);
3725 if (sk->sk_backlog.tail)
3726 __release_sock(sk);
3727
3728 if (sk->sk_prot->release_cb)
3729 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3730 tcp_release_cb, sk);
3731
3732 sock_release_ownership(sk);
3733 if (waitqueue_active(&sk->sk_lock.wq))
3734 wake_up(&sk->sk_lock.wq);
3735 spin_unlock_bh(&sk->sk_lock.slock);
3736 }
3737 EXPORT_SYMBOL(release_sock);
3738
__lock_sock_fast(struct sock * sk)3739 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3740 {
3741 might_sleep();
3742 spin_lock_bh(&sk->sk_lock.slock);
3743
3744 if (!sock_owned_by_user_nocheck(sk)) {
3745 /*
3746 * Fast path return with bottom halves disabled and
3747 * sock::sk_lock.slock held.
3748 *
3749 * The 'mutex' is not contended and holding
3750 * sock::sk_lock.slock prevents all other lockers to
3751 * proceed so the corresponding unlock_sock_fast() can
3752 * avoid the slow path of release_sock() completely and
3753 * just release slock.
3754 *
3755 * From a semantical POV this is equivalent to 'acquiring'
3756 * the 'mutex', hence the corresponding lockdep
3757 * mutex_release() has to happen in the fast path of
3758 * unlock_sock_fast().
3759 */
3760 return false;
3761 }
3762
3763 __lock_sock(sk);
3764 sk->sk_lock.owned = 1;
3765 __acquire(&sk->sk_lock.slock);
3766 spin_unlock_bh(&sk->sk_lock.slock);
3767 return true;
3768 }
3769 EXPORT_SYMBOL(__lock_sock_fast);
3770
sock_gettstamp(struct socket * sock,void __user * userstamp,bool timeval,bool time32)3771 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3772 bool timeval, bool time32)
3773 {
3774 struct sock *sk = sock->sk;
3775 struct timespec64 ts;
3776
3777 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3778 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3779 if (ts.tv_sec == -1)
3780 return -ENOENT;
3781 if (ts.tv_sec == 0) {
3782 ktime_t kt = ktime_get_real();
3783 sock_write_timestamp(sk, kt);
3784 ts = ktime_to_timespec64(kt);
3785 }
3786
3787 if (timeval)
3788 ts.tv_nsec /= 1000;
3789
3790 #ifdef CONFIG_COMPAT_32BIT_TIME
3791 if (time32)
3792 return put_old_timespec32(&ts, userstamp);
3793 #endif
3794 #ifdef CONFIG_SPARC64
3795 /* beware of padding in sparc64 timeval */
3796 if (timeval && !in_compat_syscall()) {
3797 struct __kernel_old_timeval __user tv = {
3798 .tv_sec = ts.tv_sec,
3799 .tv_usec = ts.tv_nsec,
3800 };
3801 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3802 return -EFAULT;
3803 return 0;
3804 }
3805 #endif
3806 return put_timespec64(&ts, userstamp);
3807 }
3808 EXPORT_SYMBOL(sock_gettstamp);
3809
sock_enable_timestamp(struct sock * sk,enum sock_flags flag)3810 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3811 {
3812 if (!sock_flag(sk, flag)) {
3813 unsigned long previous_flags = sk->sk_flags;
3814
3815 sock_set_flag(sk, flag);
3816 /*
3817 * we just set one of the two flags which require net
3818 * time stamping, but time stamping might have been on
3819 * already because of the other one
3820 */
3821 if (sock_needs_netstamp(sk) &&
3822 !(previous_flags & SK_FLAGS_TIMESTAMP))
3823 net_enable_timestamp();
3824 }
3825 }
3826
sock_recv_errqueue(struct sock * sk,struct msghdr * msg,int len,int level,int type)3827 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3828 int level, int type)
3829 {
3830 struct sock_exterr_skb *serr;
3831 struct sk_buff *skb;
3832 int copied, err;
3833
3834 err = -EAGAIN;
3835 skb = sock_dequeue_err_skb(sk);
3836 if (skb == NULL)
3837 goto out;
3838
3839 copied = skb->len;
3840 if (copied > len) {
3841 msg->msg_flags |= MSG_TRUNC;
3842 copied = len;
3843 }
3844 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3845 if (err)
3846 goto out_free_skb;
3847
3848 sock_recv_timestamp(msg, sk, skb);
3849
3850 serr = SKB_EXT_ERR(skb);
3851 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3852
3853 msg->msg_flags |= MSG_ERRQUEUE;
3854 err = copied;
3855
3856 out_free_skb:
3857 kfree_skb(skb);
3858 out:
3859 return err;
3860 }
3861 EXPORT_SYMBOL(sock_recv_errqueue);
3862
3863 /*
3864 * Get a socket option on an socket.
3865 *
3866 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3867 * asynchronous errors should be reported by getsockopt. We assume
3868 * this means if you specify SO_ERROR (otherwise what is the point of it).
3869 */
sock_common_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)3870 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3871 char __user *optval, int __user *optlen)
3872 {
3873 struct sock *sk = sock->sk;
3874
3875 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3876 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3877 }
3878 EXPORT_SYMBOL(sock_common_getsockopt);
3879
sock_common_recvmsg(struct socket * sock,struct msghdr * msg,size_t size,int flags)3880 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3881 int flags)
3882 {
3883 struct sock *sk = sock->sk;
3884 int addr_len = 0;
3885 int err;
3886
3887 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3888 if (err >= 0)
3889 msg->msg_namelen = addr_len;
3890 return err;
3891 }
3892 EXPORT_SYMBOL(sock_common_recvmsg);
3893
3894 /*
3895 * Set socket options on an inet socket.
3896 */
sock_common_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)3897 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3898 sockptr_t optval, unsigned int optlen)
3899 {
3900 struct sock *sk = sock->sk;
3901
3902 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3903 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3904 }
3905 EXPORT_SYMBOL(sock_common_setsockopt);
3906
sk_common_release(struct sock * sk)3907 void sk_common_release(struct sock *sk)
3908 {
3909 if (sk->sk_prot->destroy)
3910 sk->sk_prot->destroy(sk);
3911
3912 /*
3913 * Observation: when sk_common_release is called, processes have
3914 * no access to socket. But net still has.
3915 * Step one, detach it from networking:
3916 *
3917 * A. Remove from hash tables.
3918 */
3919
3920 sk->sk_prot->unhash(sk);
3921
3922 /*
3923 * In this point socket cannot receive new packets, but it is possible
3924 * that some packets are in flight because some CPU runs receiver and
3925 * did hash table lookup before we unhashed socket. They will achieve
3926 * receive queue and will be purged by socket destructor.
3927 *
3928 * Also we still have packets pending on receive queue and probably,
3929 * our own packets waiting in device queues. sock_destroy will drain
3930 * receive queue, but transmitted packets will delay socket destruction
3931 * until the last reference will be released.
3932 */
3933
3934 sock_orphan(sk);
3935
3936 xfrm_sk_free_policy(sk);
3937
3938 sock_put(sk);
3939 }
3940 EXPORT_SYMBOL(sk_common_release);
3941
sk_get_meminfo(const struct sock * sk,u32 * mem)3942 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3943 {
3944 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3945
3946 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3947 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3948 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3949 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3950 mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
3951 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3952 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3953 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3954 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3955 }
3956
3957 #ifdef CONFIG_PROC_FS
3958 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3959
sock_prot_inuse_get(struct net * net,struct proto * prot)3960 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3961 {
3962 int cpu, idx = prot->inuse_idx;
3963 int res = 0;
3964
3965 for_each_possible_cpu(cpu)
3966 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3967
3968 return res >= 0 ? res : 0;
3969 }
3970 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3971
sock_inuse_get(struct net * net)3972 int sock_inuse_get(struct net *net)
3973 {
3974 int cpu, res = 0;
3975
3976 for_each_possible_cpu(cpu)
3977 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3978
3979 return res;
3980 }
3981
3982 EXPORT_SYMBOL_GPL(sock_inuse_get);
3983
sock_inuse_init_net(struct net * net)3984 static int __net_init sock_inuse_init_net(struct net *net)
3985 {
3986 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3987 if (net->core.prot_inuse == NULL)
3988 return -ENOMEM;
3989 return 0;
3990 }
3991
sock_inuse_exit_net(struct net * net)3992 static void __net_exit sock_inuse_exit_net(struct net *net)
3993 {
3994 free_percpu(net->core.prot_inuse);
3995 }
3996
3997 static struct pernet_operations net_inuse_ops = {
3998 .init = sock_inuse_init_net,
3999 .exit = sock_inuse_exit_net,
4000 };
4001
net_inuse_init(void)4002 static __init int net_inuse_init(void)
4003 {
4004 if (register_pernet_subsys(&net_inuse_ops))
4005 panic("Cannot initialize net inuse counters");
4006
4007 return 0;
4008 }
4009
4010 core_initcall(net_inuse_init);
4011
assign_proto_idx(struct proto * prot)4012 static int assign_proto_idx(struct proto *prot)
4013 {
4014 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4015
4016 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4017 pr_err("PROTO_INUSE_NR exhausted\n");
4018 return -ENOSPC;
4019 }
4020
4021 set_bit(prot->inuse_idx, proto_inuse_idx);
4022 return 0;
4023 }
4024
release_proto_idx(struct proto * prot)4025 static void release_proto_idx(struct proto *prot)
4026 {
4027 if (prot->inuse_idx != PROTO_INUSE_NR)
4028 clear_bit(prot->inuse_idx, proto_inuse_idx);
4029 }
4030 #else
assign_proto_idx(struct proto * prot)4031 static inline int assign_proto_idx(struct proto *prot)
4032 {
4033 return 0;
4034 }
4035
release_proto_idx(struct proto * prot)4036 static inline void release_proto_idx(struct proto *prot)
4037 {
4038 }
4039
4040 #endif
4041
tw_prot_cleanup(struct timewait_sock_ops * twsk_prot)4042 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4043 {
4044 if (!twsk_prot)
4045 return;
4046 kfree(twsk_prot->twsk_slab_name);
4047 twsk_prot->twsk_slab_name = NULL;
4048 kmem_cache_destroy(twsk_prot->twsk_slab);
4049 twsk_prot->twsk_slab = NULL;
4050 }
4051
tw_prot_init(const struct proto * prot)4052 static int tw_prot_init(const struct proto *prot)
4053 {
4054 struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4055
4056 if (!twsk_prot)
4057 return 0;
4058
4059 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4060 prot->name);
4061 if (!twsk_prot->twsk_slab_name)
4062 return -ENOMEM;
4063
4064 twsk_prot->twsk_slab =
4065 kmem_cache_create(twsk_prot->twsk_slab_name,
4066 twsk_prot->twsk_obj_size, 0,
4067 SLAB_ACCOUNT | prot->slab_flags,
4068 NULL);
4069 if (!twsk_prot->twsk_slab) {
4070 pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4071 prot->name);
4072 return -ENOMEM;
4073 }
4074
4075 return 0;
4076 }
4077
req_prot_cleanup(struct request_sock_ops * rsk_prot)4078 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4079 {
4080 if (!rsk_prot)
4081 return;
4082 kfree(rsk_prot->slab_name);
4083 rsk_prot->slab_name = NULL;
4084 kmem_cache_destroy(rsk_prot->slab);
4085 rsk_prot->slab = NULL;
4086 }
4087
req_prot_init(const struct proto * prot)4088 static int req_prot_init(const struct proto *prot)
4089 {
4090 struct request_sock_ops *rsk_prot = prot->rsk_prot;
4091
4092 if (!rsk_prot)
4093 return 0;
4094
4095 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4096 prot->name);
4097 if (!rsk_prot->slab_name)
4098 return -ENOMEM;
4099
4100 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4101 rsk_prot->obj_size, 0,
4102 SLAB_ACCOUNT | prot->slab_flags,
4103 NULL);
4104
4105 if (!rsk_prot->slab) {
4106 pr_crit("%s: Can't create request sock SLAB cache!\n",
4107 prot->name);
4108 return -ENOMEM;
4109 }
4110 return 0;
4111 }
4112
proto_register(struct proto * prot,int alloc_slab)4113 int proto_register(struct proto *prot, int alloc_slab)
4114 {
4115 int ret = -ENOBUFS;
4116
4117 if (prot->memory_allocated && !prot->sysctl_mem) {
4118 pr_err("%s: missing sysctl_mem\n", prot->name);
4119 return -EINVAL;
4120 }
4121 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4122 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4123 return -EINVAL;
4124 }
4125 if (alloc_slab) {
4126 prot->slab = kmem_cache_create_usercopy(prot->name,
4127 prot->obj_size, 0,
4128 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4129 prot->slab_flags,
4130 prot->useroffset, prot->usersize,
4131 NULL);
4132
4133 if (prot->slab == NULL) {
4134 pr_crit("%s: Can't create sock SLAB cache!\n",
4135 prot->name);
4136 goto out;
4137 }
4138
4139 if (req_prot_init(prot))
4140 goto out_free_request_sock_slab;
4141
4142 if (tw_prot_init(prot))
4143 goto out_free_timewait_sock_slab;
4144 }
4145
4146 mutex_lock(&proto_list_mutex);
4147 ret = assign_proto_idx(prot);
4148 if (ret) {
4149 mutex_unlock(&proto_list_mutex);
4150 goto out_free_timewait_sock_slab;
4151 }
4152 list_add(&prot->node, &proto_list);
4153 mutex_unlock(&proto_list_mutex);
4154 return ret;
4155
4156 out_free_timewait_sock_slab:
4157 if (alloc_slab)
4158 tw_prot_cleanup(prot->twsk_prot);
4159 out_free_request_sock_slab:
4160 if (alloc_slab) {
4161 req_prot_cleanup(prot->rsk_prot);
4162
4163 kmem_cache_destroy(prot->slab);
4164 prot->slab = NULL;
4165 }
4166 out:
4167 return ret;
4168 }
4169 EXPORT_SYMBOL(proto_register);
4170
proto_unregister(struct proto * prot)4171 void proto_unregister(struct proto *prot)
4172 {
4173 mutex_lock(&proto_list_mutex);
4174 release_proto_idx(prot);
4175 list_del(&prot->node);
4176 mutex_unlock(&proto_list_mutex);
4177
4178 kmem_cache_destroy(prot->slab);
4179 prot->slab = NULL;
4180
4181 req_prot_cleanup(prot->rsk_prot);
4182 tw_prot_cleanup(prot->twsk_prot);
4183 }
4184 EXPORT_SYMBOL(proto_unregister);
4185
sock_load_diag_module(int family,int protocol)4186 int sock_load_diag_module(int family, int protocol)
4187 {
4188 if (!protocol) {
4189 if (!sock_is_registered(family))
4190 return -ENOENT;
4191
4192 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4193 NETLINK_SOCK_DIAG, family);
4194 }
4195
4196 #ifdef CONFIG_INET
4197 if (family == AF_INET &&
4198 protocol != IPPROTO_RAW &&
4199 protocol < MAX_INET_PROTOS &&
4200 !rcu_access_pointer(inet_protos[protocol]))
4201 return -ENOENT;
4202 #endif
4203
4204 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4205 NETLINK_SOCK_DIAG, family, protocol);
4206 }
4207 EXPORT_SYMBOL(sock_load_diag_module);
4208
4209 #ifdef CONFIG_PROC_FS
proto_seq_start(struct seq_file * seq,loff_t * pos)4210 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4211 __acquires(proto_list_mutex)
4212 {
4213 mutex_lock(&proto_list_mutex);
4214 return seq_list_start_head(&proto_list, *pos);
4215 }
4216
proto_seq_next(struct seq_file * seq,void * v,loff_t * pos)4217 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4218 {
4219 return seq_list_next(v, &proto_list, pos);
4220 }
4221
proto_seq_stop(struct seq_file * seq,void * v)4222 static void proto_seq_stop(struct seq_file *seq, void *v)
4223 __releases(proto_list_mutex)
4224 {
4225 mutex_unlock(&proto_list_mutex);
4226 }
4227
proto_method_implemented(const void * method)4228 static char proto_method_implemented(const void *method)
4229 {
4230 return method == NULL ? 'n' : 'y';
4231 }
sock_prot_memory_allocated(struct proto * proto)4232 static long sock_prot_memory_allocated(struct proto *proto)
4233 {
4234 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4235 }
4236
sock_prot_memory_pressure(struct proto * proto)4237 static const char *sock_prot_memory_pressure(struct proto *proto)
4238 {
4239 return proto->memory_pressure != NULL ?
4240 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4241 }
4242
proto_seq_printf(struct seq_file * seq,struct proto * proto)4243 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4244 {
4245
4246 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
4247 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4248 proto->name,
4249 proto->obj_size,
4250 sock_prot_inuse_get(seq_file_net(seq), proto),
4251 sock_prot_memory_allocated(proto),
4252 sock_prot_memory_pressure(proto),
4253 proto->max_header,
4254 proto->slab == NULL ? "no" : "yes",
4255 module_name(proto->owner),
4256 proto_method_implemented(proto->close),
4257 proto_method_implemented(proto->connect),
4258 proto_method_implemented(proto->disconnect),
4259 proto_method_implemented(proto->accept),
4260 proto_method_implemented(proto->ioctl),
4261 proto_method_implemented(proto->init),
4262 proto_method_implemented(proto->destroy),
4263 proto_method_implemented(proto->shutdown),
4264 proto_method_implemented(proto->setsockopt),
4265 proto_method_implemented(proto->getsockopt),
4266 proto_method_implemented(proto->sendmsg),
4267 proto_method_implemented(proto->recvmsg),
4268 proto_method_implemented(proto->bind),
4269 proto_method_implemented(proto->backlog_rcv),
4270 proto_method_implemented(proto->hash),
4271 proto_method_implemented(proto->unhash),
4272 proto_method_implemented(proto->get_port),
4273 proto_method_implemented(proto->enter_memory_pressure));
4274 }
4275
proto_seq_show(struct seq_file * seq,void * v)4276 static int proto_seq_show(struct seq_file *seq, void *v)
4277 {
4278 if (v == &proto_list)
4279 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4280 "protocol",
4281 "size",
4282 "sockets",
4283 "memory",
4284 "press",
4285 "maxhdr",
4286 "slab",
4287 "module",
4288 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4289 else
4290 proto_seq_printf(seq, list_entry(v, struct proto, node));
4291 return 0;
4292 }
4293
4294 static const struct seq_operations proto_seq_ops = {
4295 .start = proto_seq_start,
4296 .next = proto_seq_next,
4297 .stop = proto_seq_stop,
4298 .show = proto_seq_show,
4299 };
4300
proto_init_net(struct net * net)4301 static __net_init int proto_init_net(struct net *net)
4302 {
4303 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4304 sizeof(struct seq_net_private)))
4305 return -ENOMEM;
4306
4307 return 0;
4308 }
4309
proto_exit_net(struct net * net)4310 static __net_exit void proto_exit_net(struct net *net)
4311 {
4312 remove_proc_entry("protocols", net->proc_net);
4313 }
4314
4315
4316 static __net_initdata struct pernet_operations proto_net_ops = {
4317 .init = proto_init_net,
4318 .exit = proto_exit_net,
4319 };
4320
proto_init(void)4321 static int __init proto_init(void)
4322 {
4323 return register_pernet_subsys(&proto_net_ops);
4324 }
4325
4326 subsys_initcall(proto_init);
4327
4328 #endif /* PROC_FS */
4329
4330 #ifdef CONFIG_NET_RX_BUSY_POLL
sk_busy_loop_end(void * p,unsigned long start_time)4331 bool sk_busy_loop_end(void *p, unsigned long start_time)
4332 {
4333 struct sock *sk = p;
4334
4335 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4336 return true;
4337
4338 if (sk_is_udp(sk) &&
4339 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4340 return true;
4341
4342 return sk_busy_loop_timeout(sk, start_time);
4343 }
4344 EXPORT_SYMBOL(sk_busy_loop_end);
4345 #endif /* CONFIG_NET_RX_BUSY_POLL */
4346
sock_bind_add(struct sock * sk,struct sockaddr * addr,int addr_len)4347 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4348 {
4349 if (!sk->sk_prot->bind_add)
4350 return -EOPNOTSUPP;
4351 return sk->sk_prot->bind_add(sk, addr, addr_len);
4352 }
4353 EXPORT_SYMBOL(sock_bind_add);
4354
4355 /* Copy 'size' bytes from userspace and return `size` back to userspace */
sock_ioctl_inout(struct sock * sk,unsigned int cmd,void __user * arg,void * karg,size_t size)4356 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4357 void __user *arg, void *karg, size_t size)
4358 {
4359 int ret;
4360
4361 if (copy_from_user(karg, arg, size))
4362 return -EFAULT;
4363
4364 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4365 if (ret)
4366 return ret;
4367
4368 if (copy_to_user(arg, karg, size))
4369 return -EFAULT;
4370
4371 return 0;
4372 }
4373 EXPORT_SYMBOL(sock_ioctl_inout);
4374
4375 /* This is the most common ioctl prep function, where the result (4 bytes) is
4376 * copied back to userspace if the ioctl() returns successfully. No input is
4377 * copied from userspace as input argument.
4378 */
sock_ioctl_out(struct sock * sk,unsigned int cmd,void __user * arg)4379 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4380 {
4381 int ret, karg = 0;
4382
4383 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4384 if (ret)
4385 return ret;
4386
4387 return put_user(karg, (int __user *)arg);
4388 }
4389
4390 /* A wrapper around sock ioctls, which copies the data from userspace
4391 * (depending on the protocol/ioctl), and copies back the result to userspace.
4392 * The main motivation for this function is to pass kernel memory to the
4393 * protocol ioctl callbacks, instead of userspace memory.
4394 */
sk_ioctl(struct sock * sk,unsigned int cmd,void __user * arg)4395 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4396 {
4397 int rc = 1;
4398
4399 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4400 rc = ipmr_sk_ioctl(sk, cmd, arg);
4401 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4402 rc = ip6mr_sk_ioctl(sk, cmd, arg);
4403 else if (sk_is_phonet(sk))
4404 rc = phonet_sk_ioctl(sk, cmd, arg);
4405
4406 /* If ioctl was processed, returns its value */
4407 if (rc <= 0)
4408 return rc;
4409
4410 /* Otherwise call the default handler */
4411 return sock_ioctl_out(sk, cmd, arg);
4412 }
4413 EXPORT_SYMBOL(sk_ioctl);
4414
sock_struct_check(void)4415 static int __init sock_struct_check(void)
4416 {
4417 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4418 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4419 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4420 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4421 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4422
4423 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4424 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4425 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4426 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4427 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4428 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4429 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4430 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4431 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4432
4433 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4434 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4435 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4436
4437 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4438 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4439 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4440 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4441
4442 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4443 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4444 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_sndbuf);
4445 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4446 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4447 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4448 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4449 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4450 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4451 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm);
4452 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status);
4453 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4454 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4455 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4456 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4457 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4458
4459 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4460 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4461 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4462 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4463 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4464 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4465 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4466 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4467 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4468 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4469 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4470 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4471 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4472 return 0;
4473 }
4474
4475 core_initcall(sock_struct_check);
4476