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