1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
4 *		operating system.  INET is implemented using the  BSD Socket
5 *		interface as the means of communication with the user level.
6 *
7 *		Generic socket support routines. Memory allocators, socket lock/release
8 *		handler for protocols to use and generic option handler.
9 *
10 * Authors:	Ross Biro
11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *		Florian La Roche, <flla@stud.uni-sb.de>
13 *		Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 *		Alan Cox	: 	Numerous verify_area() problems
17 *		Alan Cox	:	Connecting on a connecting socket
18 *					now returns an error for tcp.
19 *		Alan Cox	:	sock->protocol is set correctly.
20 *					and is not sometimes left as 0.
21 *		Alan Cox	:	connect handles icmp errors on a
22 *					connect properly. Unfortunately there
23 *					is a restart syscall nasty there. I
24 *					can't match BSD without hacking the C
25 *					library. Ideas urgently sought!
26 *		Alan Cox	:	Disallow bind() to addresses that are
27 *					not ours - especially broadcast ones!!
28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30 *					instead they leave that for the DESTROY timer.
31 *		Alan Cox	:	Clean up error flag in accept
32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33 *					was buggy. Put a remove_sock() in the handler
34 *					for memory when we hit 0. Also altered the timer
35 *					code. The ACK stuff can wait and needs major
36 *					TCP layer surgery.
37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38 *					and fixed timer/inet_bh race.
39 *		Alan Cox	:	Added zapped flag for TCP
40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47 *	Pauline Middelink	:	identd support
48 *		Alan Cox	:	Fixed connect() taking signals I think.
49 *		Alan Cox	:	SO_LINGER supported
50 *		Alan Cox	:	Error reporting fixes
51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52 *		Alan Cox	:	inet sockets don't set sk->type!
53 *		Alan Cox	:	Split socket option code
54 *		Alan Cox	:	Callbacks
55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56 *		Alex		:	Removed restriction on inet fioctl
57 *		Alan Cox	:	Splitting INET from NET core
58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60 *		Alan Cox	:	Split IP from generic code
61 *		Alan Cox	:	New kfree_skbmem()
62 *		Alan Cox	:	Make SO_DEBUG superuser only.
63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64 *					(compatibility fix)
65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66 *		Alan Cox	:	Allocator for a socket is settable.
67 *		Alan Cox	:	SO_ERROR includes soft errors.
68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69 *		Alan Cox	: 	Generic socket allocation to make hooks
70 *					easier (suggested by Craig Metz).
71 *		Michael Pall	:	SO_ERROR returns positive errno again
72 *              Steve Whitehouse:       Added default destructor to free
73 *                                      protocol private data.
74 *              Steve Whitehouse:       Added various other default routines
75 *                                      common to several socket families.
76 *              Chris Evans     :       Call suser() check last on F_SETOWN
77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79 *		Andi Kleen	:	Fix write_space callback
80 *		Chris Evans	:	Security fixes - signedness again
81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 */
85
86#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87
88#include <asm/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 <net/net_namespace.h>
128#include <net/request_sock.h>
129#include <net/sock.h>
130#include <linux/net_tstamp.h>
131#include <net/xfrm.h>
132#include <linux/ipsec.h>
133#include <net/cls_cgroup.h>
134#include <net/netprio_cgroup.h>
135#include <linux/sock_diag.h>
136
137#include <linux/filter.h>
138#include <net/sock_reuseport.h>
139#include <net/bpf_sk_storage.h>
140
141#include <trace/events/sock.h>
142
143#include <net/tcp.h>
144#include <net/busy_poll.h>
145#include <net/phonet/phonet.h>
146
147#include <linux/ethtool.h>
148
149#include "dev.h"
150
151static DEFINE_MUTEX(proto_list_mutex);
152static LIST_HEAD(proto_list);
153
154static void sock_def_write_space_wfree(struct sock *sk);
155static void sock_def_write_space(struct sock *sk);
156
157/**
158 * sk_ns_capable - General socket capability test
159 * @sk: Socket to use a capability on or through
160 * @user_ns: The user namespace of the capability to use
161 * @cap: The capability to use
162 *
163 * Test to see if the opener of the socket had when the socket was
164 * created and the current process has the capability @cap in the user
165 * namespace @user_ns.
166 */
167bool sk_ns_capable(const struct sock *sk,
168		   struct user_namespace *user_ns, int cap)
169{
170	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
171		ns_capable(user_ns, cap);
172}
173EXPORT_SYMBOL(sk_ns_capable);
174
175/**
176 * sk_capable - Socket global capability test
177 * @sk: Socket to use a capability on or through
178 * @cap: The global capability to use
179 *
180 * Test to see if the opener of the socket had when the socket was
181 * created and the current process has the capability @cap in all user
182 * namespaces.
183 */
184bool sk_capable(const struct sock *sk, int cap)
185{
186	return sk_ns_capable(sk, &init_user_ns, cap);
187}
188EXPORT_SYMBOL(sk_capable);
189
190/**
191 * sk_net_capable - Network namespace socket capability test
192 * @sk: Socket to use a capability on or through
193 * @cap: The capability to use
194 *
195 * Test to see if the opener of the socket had when the socket was created
196 * and the current process has the capability @cap over the network namespace
197 * the socket is a member of.
198 */
199bool sk_net_capable(const struct sock *sk, int cap)
200{
201	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
202}
203EXPORT_SYMBOL(sk_net_capable);
204
205/*
206 * Each address family might have different locking rules, so we have
207 * one slock key per address family and separate keys for internal and
208 * userspace sockets.
209 */
210static struct lock_class_key af_family_keys[AF_MAX];
211static struct lock_class_key af_family_kern_keys[AF_MAX];
212static struct lock_class_key af_family_slock_keys[AF_MAX];
213static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
214
215/*
216 * Make lock validator output more readable. (we pre-construct these
217 * strings build-time, so that runtime initialization of socket
218 * locks is fast):
219 */
220
221#define _sock_locks(x)						  \
222  x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
223  x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
224  x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
225  x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
226  x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
227  x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
228  x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
229  x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
230  x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
231  x "27"       ,	x "28"          ,	x "AF_CAN"      , \
232  x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
233  x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
234  x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
235  x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
236  x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
237  x "AF_MCTP"  , \
238  x "AF_MAX"
239
240static const char *const af_family_key_strings[AF_MAX+1] = {
241	_sock_locks("sk_lock-")
242};
243static const char *const af_family_slock_key_strings[AF_MAX+1] = {
244	_sock_locks("slock-")
245};
246static const char *const af_family_clock_key_strings[AF_MAX+1] = {
247	_sock_locks("clock-")
248};
249
250static const char *const af_family_kern_key_strings[AF_MAX+1] = {
251	_sock_locks("k-sk_lock-")
252};
253static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
254	_sock_locks("k-slock-")
255};
256static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
257	_sock_locks("k-clock-")
258};
259static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
260	_sock_locks("rlock-")
261};
262static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
263	_sock_locks("wlock-")
264};
265static const char *const af_family_elock_key_strings[AF_MAX+1] = {
266	_sock_locks("elock-")
267};
268
269/*
270 * sk_callback_lock and sk queues locking rules are per-address-family,
271 * so split the lock classes by using a per-AF key:
272 */
273static struct lock_class_key af_callback_keys[AF_MAX];
274static struct lock_class_key af_rlock_keys[AF_MAX];
275static struct lock_class_key af_wlock_keys[AF_MAX];
276static struct lock_class_key af_elock_keys[AF_MAX];
277static struct lock_class_key af_kern_callback_keys[AF_MAX];
278
279/* Run time adjustable parameters. */
280__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
281EXPORT_SYMBOL(sysctl_wmem_max);
282__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
283EXPORT_SYMBOL(sysctl_rmem_max);
284__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
285__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
286int sysctl_mem_pcpu_rsv __read_mostly = SK_MEMORY_PCPU_RESERVE;
287
288int sysctl_tstamp_allow_data __read_mostly = 1;
289
290DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
291EXPORT_SYMBOL_GPL(memalloc_socks_key);
292
293/**
294 * sk_set_memalloc - sets %SOCK_MEMALLOC
295 * @sk: socket to set it on
296 *
297 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
298 * It's the responsibility of the admin to adjust min_free_kbytes
299 * to meet the requirements
300 */
301void sk_set_memalloc(struct sock *sk)
302{
303	sock_set_flag(sk, SOCK_MEMALLOC);
304	sk->sk_allocation |= __GFP_MEMALLOC;
305	static_branch_inc(&memalloc_socks_key);
306}
307EXPORT_SYMBOL_GPL(sk_set_memalloc);
308
309void sk_clear_memalloc(struct sock *sk)
310{
311	sock_reset_flag(sk, SOCK_MEMALLOC);
312	sk->sk_allocation &= ~__GFP_MEMALLOC;
313	static_branch_dec(&memalloc_socks_key);
314
315	/*
316	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
317	 * progress of swapping. SOCK_MEMALLOC may be cleared while
318	 * it has rmem allocations due to the last swapfile being deactivated
319	 * but there is a risk that the socket is unusable due to exceeding
320	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
321	 */
322	sk_mem_reclaim(sk);
323}
324EXPORT_SYMBOL_GPL(sk_clear_memalloc);
325
326int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
327{
328	int ret;
329	unsigned int noreclaim_flag;
330
331	/* these should have been dropped before queueing */
332	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
333
334	noreclaim_flag = memalloc_noreclaim_save();
335	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
336				 tcp_v6_do_rcv,
337				 tcp_v4_do_rcv,
338				 sk, skb);
339	memalloc_noreclaim_restore(noreclaim_flag);
340
341	return ret;
342}
343EXPORT_SYMBOL(__sk_backlog_rcv);
344
345void sk_error_report(struct sock *sk)
346{
347	sk->sk_error_report(sk);
348
349	switch (sk->sk_family) {
350	case AF_INET:
351		fallthrough;
352	case AF_INET6:
353		trace_inet_sk_error_report(sk);
354		break;
355	default:
356		break;
357	}
358}
359EXPORT_SYMBOL(sk_error_report);
360
361int sock_get_timeout(long timeo, void *optval, bool old_timeval)
362{
363	struct __kernel_sock_timeval tv;
364
365	if (timeo == MAX_SCHEDULE_TIMEOUT) {
366		tv.tv_sec = 0;
367		tv.tv_usec = 0;
368	} else {
369		tv.tv_sec = timeo / HZ;
370		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
371	}
372
373	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
374		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
375		*(struct old_timeval32 *)optval = tv32;
376		return sizeof(tv32);
377	}
378
379	if (old_timeval) {
380		struct __kernel_old_timeval old_tv;
381		old_tv.tv_sec = tv.tv_sec;
382		old_tv.tv_usec = tv.tv_usec;
383		*(struct __kernel_old_timeval *)optval = old_tv;
384		return sizeof(old_tv);
385	}
386
387	*(struct __kernel_sock_timeval *)optval = tv;
388	return sizeof(tv);
389}
390EXPORT_SYMBOL(sock_get_timeout);
391
392int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
393			   sockptr_t optval, int optlen, bool old_timeval)
394{
395	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
396		struct old_timeval32 tv32;
397
398		if (optlen < sizeof(tv32))
399			return -EINVAL;
400
401		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
402			return -EFAULT;
403		tv->tv_sec = tv32.tv_sec;
404		tv->tv_usec = tv32.tv_usec;
405	} else if (old_timeval) {
406		struct __kernel_old_timeval old_tv;
407
408		if (optlen < sizeof(old_tv))
409			return -EINVAL;
410		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
411			return -EFAULT;
412		tv->tv_sec = old_tv.tv_sec;
413		tv->tv_usec = old_tv.tv_usec;
414	} else {
415		if (optlen < sizeof(*tv))
416			return -EINVAL;
417		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
418			return -EFAULT;
419	}
420
421	return 0;
422}
423EXPORT_SYMBOL(sock_copy_user_timeval);
424
425static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
426			    bool old_timeval)
427{
428	struct __kernel_sock_timeval tv;
429	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
430	long val;
431
432	if (err)
433		return err;
434
435	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
436		return -EDOM;
437
438	if (tv.tv_sec < 0) {
439		static int warned __read_mostly;
440
441		WRITE_ONCE(*timeo_p, 0);
442		if (warned < 10 && net_ratelimit()) {
443			warned++;
444			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
445				__func__, current->comm, task_pid_nr(current));
446		}
447		return 0;
448	}
449	val = MAX_SCHEDULE_TIMEOUT;
450	if ((tv.tv_sec || tv.tv_usec) &&
451	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
452		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
453						    USEC_PER_SEC / HZ);
454	WRITE_ONCE(*timeo_p, val);
455	return 0;
456}
457
458static bool sock_needs_netstamp(const struct sock *sk)
459{
460	switch (sk->sk_family) {
461	case AF_UNSPEC:
462	case AF_UNIX:
463		return false;
464	default:
465		return true;
466	}
467}
468
469static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
470{
471	if (sk->sk_flags & flags) {
472		sk->sk_flags &= ~flags;
473		if (sock_needs_netstamp(sk) &&
474		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
475			net_disable_timestamp();
476	}
477}
478
479
480int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
481{
482	unsigned long flags;
483	struct sk_buff_head *list = &sk->sk_receive_queue;
484
485	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
486		atomic_inc(&sk->sk_drops);
487		trace_sock_rcvqueue_full(sk, skb);
488		return -ENOMEM;
489	}
490
491	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
492		atomic_inc(&sk->sk_drops);
493		return -ENOBUFS;
494	}
495
496	skb->dev = NULL;
497	skb_set_owner_r(skb, sk);
498
499	/* we escape from rcu protected region, make sure we dont leak
500	 * a norefcounted dst
501	 */
502	skb_dst_force(skb);
503
504	spin_lock_irqsave(&list->lock, flags);
505	sock_skb_set_dropcount(sk, skb);
506	__skb_queue_tail(list, skb);
507	spin_unlock_irqrestore(&list->lock, flags);
508
509	if (!sock_flag(sk, SOCK_DEAD))
510		sk->sk_data_ready(sk);
511	return 0;
512}
513EXPORT_SYMBOL(__sock_queue_rcv_skb);
514
515int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
516			      enum skb_drop_reason *reason)
517{
518	enum skb_drop_reason drop_reason;
519	int err;
520
521	err = sk_filter(sk, skb);
522	if (err) {
523		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
524		goto out;
525	}
526	err = __sock_queue_rcv_skb(sk, skb);
527	switch (err) {
528	case -ENOMEM:
529		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
530		break;
531	case -ENOBUFS:
532		drop_reason = SKB_DROP_REASON_PROTO_MEM;
533		break;
534	default:
535		drop_reason = SKB_NOT_DROPPED_YET;
536		break;
537	}
538out:
539	if (reason)
540		*reason = drop_reason;
541	return err;
542}
543EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
544
545int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
546		     const int nested, unsigned int trim_cap, bool refcounted)
547{
548	int rc = NET_RX_SUCCESS;
549
550	if (sk_filter_trim_cap(sk, skb, trim_cap))
551		goto discard_and_relse;
552
553	skb->dev = NULL;
554
555	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
556		atomic_inc(&sk->sk_drops);
557		goto discard_and_relse;
558	}
559	if (nested)
560		bh_lock_sock_nested(sk);
561	else
562		bh_lock_sock(sk);
563	if (!sock_owned_by_user(sk)) {
564		/*
565		 * trylock + unlock semantics:
566		 */
567		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
568
569		rc = sk_backlog_rcv(sk, skb);
570
571		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
572	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
573		bh_unlock_sock(sk);
574		atomic_inc(&sk->sk_drops);
575		goto discard_and_relse;
576	}
577
578	bh_unlock_sock(sk);
579out:
580	if (refcounted)
581		sock_put(sk);
582	return rc;
583discard_and_relse:
584	kfree_skb(skb);
585	goto out;
586}
587EXPORT_SYMBOL(__sk_receive_skb);
588
589INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
590							  u32));
591INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
592							   u32));
593struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
594{
595	struct dst_entry *dst = __sk_dst_get(sk);
596
597	if (dst && dst->obsolete &&
598	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
599			       dst, cookie) == NULL) {
600		sk_tx_queue_clear(sk);
601		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
602		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
603		dst_release(dst);
604		return NULL;
605	}
606
607	return dst;
608}
609EXPORT_SYMBOL(__sk_dst_check);
610
611struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
612{
613	struct dst_entry *dst = sk_dst_get(sk);
614
615	if (dst && dst->obsolete &&
616	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
617			       dst, cookie) == NULL) {
618		sk_dst_reset(sk);
619		dst_release(dst);
620		return NULL;
621	}
622
623	return dst;
624}
625EXPORT_SYMBOL(sk_dst_check);
626
627static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
628{
629	int ret = -ENOPROTOOPT;
630#ifdef CONFIG_NETDEVICES
631	struct net *net = sock_net(sk);
632
633	/* Sorry... */
634	ret = -EPERM;
635	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
636		goto out;
637
638	ret = -EINVAL;
639	if (ifindex < 0)
640		goto out;
641
642	/* Paired with all READ_ONCE() done locklessly. */
643	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
644
645	if (sk->sk_prot->rehash)
646		sk->sk_prot->rehash(sk);
647	sk_dst_reset(sk);
648
649	ret = 0;
650
651out:
652#endif
653
654	return ret;
655}
656
657int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
658{
659	int ret;
660
661	if (lock_sk)
662		lock_sock(sk);
663	ret = sock_bindtoindex_locked(sk, ifindex);
664	if (lock_sk)
665		release_sock(sk);
666
667	return ret;
668}
669EXPORT_SYMBOL(sock_bindtoindex);
670
671static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
672{
673	int ret = -ENOPROTOOPT;
674#ifdef CONFIG_NETDEVICES
675	struct net *net = sock_net(sk);
676	char devname[IFNAMSIZ];
677	int index;
678
679	ret = -EINVAL;
680	if (optlen < 0)
681		goto out;
682
683	/* Bind this socket to a particular device like "eth0",
684	 * as specified in the passed interface name. If the
685	 * name is "" or the option length is zero the socket
686	 * is not bound.
687	 */
688	if (optlen > IFNAMSIZ - 1)
689		optlen = IFNAMSIZ - 1;
690	memset(devname, 0, sizeof(devname));
691
692	ret = -EFAULT;
693	if (copy_from_sockptr(devname, optval, optlen))
694		goto out;
695
696	index = 0;
697	if (devname[0] != '\0') {
698		struct net_device *dev;
699
700		rcu_read_lock();
701		dev = dev_get_by_name_rcu(net, devname);
702		if (dev)
703			index = dev->ifindex;
704		rcu_read_unlock();
705		ret = -ENODEV;
706		if (!dev)
707			goto out;
708	}
709
710	sockopt_lock_sock(sk);
711	ret = sock_bindtoindex_locked(sk, index);
712	sockopt_release_sock(sk);
713out:
714#endif
715
716	return ret;
717}
718
719static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
720				sockptr_t optlen, int len)
721{
722	int ret = -ENOPROTOOPT;
723#ifdef CONFIG_NETDEVICES
724	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
725	struct net *net = sock_net(sk);
726	char devname[IFNAMSIZ];
727
728	if (bound_dev_if == 0) {
729		len = 0;
730		goto zero;
731	}
732
733	ret = -EINVAL;
734	if (len < IFNAMSIZ)
735		goto out;
736
737	ret = netdev_get_name(net, devname, bound_dev_if);
738	if (ret)
739		goto out;
740
741	len = strlen(devname) + 1;
742
743	ret = -EFAULT;
744	if (copy_to_sockptr(optval, devname, len))
745		goto out;
746
747zero:
748	ret = -EFAULT;
749	if (copy_to_sockptr(optlen, &len, sizeof(int)))
750		goto out;
751
752	ret = 0;
753
754out:
755#endif
756
757	return ret;
758}
759
760bool sk_mc_loop(const struct sock *sk)
761{
762	if (dev_recursion_level())
763		return false;
764	if (!sk)
765		return true;
766	/* IPV6_ADDRFORM can change sk->sk_family under us. */
767	switch (READ_ONCE(sk->sk_family)) {
768	case AF_INET:
769		return inet_test_bit(MC_LOOP, sk);
770#if IS_ENABLED(CONFIG_IPV6)
771	case AF_INET6:
772		return inet6_test_bit(MC6_LOOP, sk);
773#endif
774	}
775	WARN_ON_ONCE(1);
776	return true;
777}
778EXPORT_SYMBOL(sk_mc_loop);
779
780void sock_set_reuseaddr(struct sock *sk)
781{
782	lock_sock(sk);
783	sk->sk_reuse = SK_CAN_REUSE;
784	release_sock(sk);
785}
786EXPORT_SYMBOL(sock_set_reuseaddr);
787
788void sock_set_reuseport(struct sock *sk)
789{
790	lock_sock(sk);
791	sk->sk_reuseport = true;
792	release_sock(sk);
793}
794EXPORT_SYMBOL(sock_set_reuseport);
795
796void sock_no_linger(struct sock *sk)
797{
798	lock_sock(sk);
799	WRITE_ONCE(sk->sk_lingertime, 0);
800	sock_set_flag(sk, SOCK_LINGER);
801	release_sock(sk);
802}
803EXPORT_SYMBOL(sock_no_linger);
804
805void sock_set_priority(struct sock *sk, u32 priority)
806{
807	WRITE_ONCE(sk->sk_priority, priority);
808}
809EXPORT_SYMBOL(sock_set_priority);
810
811void sock_set_sndtimeo(struct sock *sk, s64 secs)
812{
813	lock_sock(sk);
814	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
815		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
816	else
817		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
818	release_sock(sk);
819}
820EXPORT_SYMBOL(sock_set_sndtimeo);
821
822static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
823{
824	if (val)  {
825		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
826		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
827		sock_set_flag(sk, SOCK_RCVTSTAMP);
828		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
829	} else {
830		sock_reset_flag(sk, SOCK_RCVTSTAMP);
831		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
832	}
833}
834
835void sock_enable_timestamps(struct sock *sk)
836{
837	lock_sock(sk);
838	__sock_set_timestamps(sk, true, false, true);
839	release_sock(sk);
840}
841EXPORT_SYMBOL(sock_enable_timestamps);
842
843void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
844{
845	switch (optname) {
846	case SO_TIMESTAMP_OLD:
847		__sock_set_timestamps(sk, valbool, false, false);
848		break;
849	case SO_TIMESTAMP_NEW:
850		__sock_set_timestamps(sk, valbool, true, false);
851		break;
852	case SO_TIMESTAMPNS_OLD:
853		__sock_set_timestamps(sk, valbool, false, true);
854		break;
855	case SO_TIMESTAMPNS_NEW:
856		__sock_set_timestamps(sk, valbool, true, true);
857		break;
858	}
859}
860
861static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
862{
863	struct net *net = sock_net(sk);
864	struct net_device *dev = NULL;
865	bool match = false;
866	int *vclock_index;
867	int i, num;
868
869	if (sk->sk_bound_dev_if)
870		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
871
872	if (!dev) {
873		pr_err("%s: sock not bind to device\n", __func__);
874		return -EOPNOTSUPP;
875	}
876
877	num = ethtool_get_phc_vclocks(dev, &vclock_index);
878	dev_put(dev);
879
880	for (i = 0; i < num; i++) {
881		if (*(vclock_index + i) == phc_index) {
882			match = true;
883			break;
884		}
885	}
886
887	if (num > 0)
888		kfree(vclock_index);
889
890	if (!match)
891		return -EINVAL;
892
893	WRITE_ONCE(sk->sk_bind_phc, phc_index);
894
895	return 0;
896}
897
898int sock_set_timestamping(struct sock *sk, int optname,
899			  struct so_timestamping timestamping)
900{
901	int val = timestamping.flags;
902	int ret;
903
904	if (val & ~SOF_TIMESTAMPING_MASK)
905		return -EINVAL;
906
907	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
908	    !(val & SOF_TIMESTAMPING_OPT_ID))
909		return -EINVAL;
910
911	if (val & SOF_TIMESTAMPING_OPT_ID &&
912	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
913		if (sk_is_tcp(sk)) {
914			if ((1 << sk->sk_state) &
915			    (TCPF_CLOSE | TCPF_LISTEN))
916				return -EINVAL;
917			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
918				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
919			else
920				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
921		} else {
922			atomic_set(&sk->sk_tskey, 0);
923		}
924	}
925
926	if (val & SOF_TIMESTAMPING_OPT_STATS &&
927	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
928		return -EINVAL;
929
930	if (val & SOF_TIMESTAMPING_BIND_PHC) {
931		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
932		if (ret)
933			return ret;
934	}
935
936	WRITE_ONCE(sk->sk_tsflags, val);
937	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
938
939	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
940		sock_enable_timestamp(sk,
941				      SOCK_TIMESTAMPING_RX_SOFTWARE);
942	else
943		sock_disable_timestamp(sk,
944				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
945	return 0;
946}
947
948void sock_set_keepalive(struct sock *sk)
949{
950	lock_sock(sk);
951	if (sk->sk_prot->keepalive)
952		sk->sk_prot->keepalive(sk, true);
953	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
954	release_sock(sk);
955}
956EXPORT_SYMBOL(sock_set_keepalive);
957
958static void __sock_set_rcvbuf(struct sock *sk, int val)
959{
960	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
961	 * as a negative value.
962	 */
963	val = min_t(int, val, INT_MAX / 2);
964	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
965
966	/* We double it on the way in to account for "struct sk_buff" etc.
967	 * overhead.   Applications assume that the SO_RCVBUF setting they make
968	 * will allow that much actual data to be received on that socket.
969	 *
970	 * Applications are unaware that "struct sk_buff" and other overheads
971	 * allocate from the receive buffer during socket buffer allocation.
972	 *
973	 * And after considering the possible alternatives, returning the value
974	 * we actually used in getsockopt is the most desirable behavior.
975	 */
976	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
977}
978
979void sock_set_rcvbuf(struct sock *sk, int val)
980{
981	lock_sock(sk);
982	__sock_set_rcvbuf(sk, val);
983	release_sock(sk);
984}
985EXPORT_SYMBOL(sock_set_rcvbuf);
986
987static void __sock_set_mark(struct sock *sk, u32 val)
988{
989	if (val != sk->sk_mark) {
990		WRITE_ONCE(sk->sk_mark, val);
991		sk_dst_reset(sk);
992	}
993}
994
995void sock_set_mark(struct sock *sk, u32 val)
996{
997	lock_sock(sk);
998	__sock_set_mark(sk, val);
999	release_sock(sk);
1000}
1001EXPORT_SYMBOL(sock_set_mark);
1002
1003static void sock_release_reserved_memory(struct sock *sk, int bytes)
1004{
1005	/* Round down bytes to multiple of pages */
1006	bytes = round_down(bytes, PAGE_SIZE);
1007
1008	WARN_ON(bytes > sk->sk_reserved_mem);
1009	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1010	sk_mem_reclaim(sk);
1011}
1012
1013static int sock_reserve_memory(struct sock *sk, int bytes)
1014{
1015	long allocated;
1016	bool charged;
1017	int pages;
1018
1019	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1020		return -EOPNOTSUPP;
1021
1022	if (!bytes)
1023		return 0;
1024
1025	pages = sk_mem_pages(bytes);
1026
1027	/* pre-charge to memcg */
1028	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1029					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1030	if (!charged)
1031		return -ENOMEM;
1032
1033	/* pre-charge to forward_alloc */
1034	sk_memory_allocated_add(sk, pages);
1035	allocated = sk_memory_allocated(sk);
1036	/* If the system goes into memory pressure with this
1037	 * precharge, give up and return error.
1038	 */
1039	if (allocated > sk_prot_mem_limits(sk, 1)) {
1040		sk_memory_allocated_sub(sk, pages);
1041		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1042		return -ENOMEM;
1043	}
1044	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1045
1046	WRITE_ONCE(sk->sk_reserved_mem,
1047		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1048
1049	return 0;
1050}
1051
1052void sockopt_lock_sock(struct sock *sk)
1053{
1054	/* When current->bpf_ctx is set, the setsockopt is called from
1055	 * a bpf prog.  bpf has ensured the sk lock has been
1056	 * acquired before calling setsockopt().
1057	 */
1058	if (has_current_bpf_ctx())
1059		return;
1060
1061	lock_sock(sk);
1062}
1063EXPORT_SYMBOL(sockopt_lock_sock);
1064
1065void sockopt_release_sock(struct sock *sk)
1066{
1067	if (has_current_bpf_ctx())
1068		return;
1069
1070	release_sock(sk);
1071}
1072EXPORT_SYMBOL(sockopt_release_sock);
1073
1074bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1075{
1076	return has_current_bpf_ctx() || ns_capable(ns, cap);
1077}
1078EXPORT_SYMBOL(sockopt_ns_capable);
1079
1080bool sockopt_capable(int cap)
1081{
1082	return has_current_bpf_ctx() || capable(cap);
1083}
1084EXPORT_SYMBOL(sockopt_capable);
1085
1086/*
1087 *	This is meant for all protocols to use and covers goings on
1088 *	at the socket level. Everything here is generic.
1089 */
1090
1091int sk_setsockopt(struct sock *sk, int level, int optname,
1092		  sockptr_t optval, unsigned int optlen)
1093{
1094	struct so_timestamping timestamping;
1095	struct socket *sock = sk->sk_socket;
1096	struct sock_txtime sk_txtime;
1097	int val;
1098	int valbool;
1099	struct linger ling;
1100	int ret = 0;
1101
1102	/*
1103	 *	Options without arguments
1104	 */
1105
1106	if (optname == SO_BINDTODEVICE)
1107		return sock_setbindtodevice(sk, optval, optlen);
1108
1109	if (optlen < sizeof(int))
1110		return -EINVAL;
1111
1112	if (copy_from_sockptr(&val, optval, sizeof(val)))
1113		return -EFAULT;
1114
1115	valbool = val ? 1 : 0;
1116
1117	/* handle options which do not require locking the socket. */
1118	switch (optname) {
1119	case SO_PRIORITY:
1120		if ((val >= 0 && val <= 6) ||
1121		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1122		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1123			sock_set_priority(sk, val);
1124			return 0;
1125		}
1126		return -EPERM;
1127	case SO_PASSSEC:
1128		assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1129		return 0;
1130	case SO_PASSCRED:
1131		assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1132		return 0;
1133	case SO_PASSPIDFD:
1134		assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1135		return 0;
1136	case SO_TYPE:
1137	case SO_PROTOCOL:
1138	case SO_DOMAIN:
1139	case SO_ERROR:
1140		return -ENOPROTOOPT;
1141#ifdef CONFIG_NET_RX_BUSY_POLL
1142	case SO_BUSY_POLL:
1143		if (val < 0)
1144			return -EINVAL;
1145		WRITE_ONCE(sk->sk_ll_usec, val);
1146		return 0;
1147	case SO_PREFER_BUSY_POLL:
1148		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1149			return -EPERM;
1150		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1151		return 0;
1152	case SO_BUSY_POLL_BUDGET:
1153		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1154		    !sockopt_capable(CAP_NET_ADMIN))
1155			return -EPERM;
1156		if (val < 0 || val > U16_MAX)
1157			return -EINVAL;
1158		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1159		return 0;
1160#endif
1161	case SO_MAX_PACING_RATE:
1162		{
1163		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1164		unsigned long pacing_rate;
1165
1166		if (sizeof(ulval) != sizeof(val) &&
1167		    optlen >= sizeof(ulval) &&
1168		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1169			return -EFAULT;
1170		}
1171		if (ulval != ~0UL)
1172			cmpxchg(&sk->sk_pacing_status,
1173				SK_PACING_NONE,
1174				SK_PACING_NEEDED);
1175		/* Pairs with READ_ONCE() from sk_getsockopt() */
1176		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1177		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1178		if (ulval < pacing_rate)
1179			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1180		return 0;
1181		}
1182	case SO_TXREHASH:
1183		if (val < -1 || val > 1)
1184			return -EINVAL;
1185		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1186			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1187		/* Paired with READ_ONCE() in tcp_rtx_synack()
1188		 * and sk_getsockopt().
1189		 */
1190		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1191		return 0;
1192	case SO_PEEK_OFF:
1193		{
1194		int (*set_peek_off)(struct sock *sk, int val);
1195
1196		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1197		if (set_peek_off)
1198			ret = set_peek_off(sk, val);
1199		else
1200			ret = -EOPNOTSUPP;
1201		return ret;
1202		}
1203	}
1204
1205	sockopt_lock_sock(sk);
1206
1207	switch (optname) {
1208	case SO_DEBUG:
1209		if (val && !sockopt_capable(CAP_NET_ADMIN))
1210			ret = -EACCES;
1211		else
1212			sock_valbool_flag(sk, SOCK_DBG, valbool);
1213		break;
1214	case SO_REUSEADDR:
1215		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1216		break;
1217	case SO_REUSEPORT:
1218		sk->sk_reuseport = valbool;
1219		break;
1220	case SO_DONTROUTE:
1221		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1222		sk_dst_reset(sk);
1223		break;
1224	case SO_BROADCAST:
1225		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1226		break;
1227	case SO_SNDBUF:
1228		/* Don't error on this BSD doesn't and if you think
1229		 * about it this is right. Otherwise apps have to
1230		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1231		 * are treated in BSD as hints
1232		 */
1233		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1234set_sndbuf:
1235		/* Ensure val * 2 fits into an int, to prevent max_t()
1236		 * from treating it as a negative value.
1237		 */
1238		val = min_t(int, val, INT_MAX / 2);
1239		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1240		WRITE_ONCE(sk->sk_sndbuf,
1241			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1242		/* Wake up sending tasks if we upped the value. */
1243		sk->sk_write_space(sk);
1244		break;
1245
1246	case SO_SNDBUFFORCE:
1247		if (!sockopt_capable(CAP_NET_ADMIN)) {
1248			ret = -EPERM;
1249			break;
1250		}
1251
1252		/* No negative values (to prevent underflow, as val will be
1253		 * multiplied by 2).
1254		 */
1255		if (val < 0)
1256			val = 0;
1257		goto set_sndbuf;
1258
1259	case SO_RCVBUF:
1260		/* Don't error on this BSD doesn't and if you think
1261		 * about it this is right. Otherwise apps have to
1262		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1263		 * are treated in BSD as hints
1264		 */
1265		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1266		break;
1267
1268	case SO_RCVBUFFORCE:
1269		if (!sockopt_capable(CAP_NET_ADMIN)) {
1270			ret = -EPERM;
1271			break;
1272		}
1273
1274		/* No negative values (to prevent underflow, as val will be
1275		 * multiplied by 2).
1276		 */
1277		__sock_set_rcvbuf(sk, max(val, 0));
1278		break;
1279
1280	case SO_KEEPALIVE:
1281		if (sk->sk_prot->keepalive)
1282			sk->sk_prot->keepalive(sk, valbool);
1283		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1284		break;
1285
1286	case SO_OOBINLINE:
1287		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1288		break;
1289
1290	case SO_NO_CHECK:
1291		sk->sk_no_check_tx = valbool;
1292		break;
1293
1294	case SO_LINGER:
1295		if (optlen < sizeof(ling)) {
1296			ret = -EINVAL;	/* 1003.1g */
1297			break;
1298		}
1299		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1300			ret = -EFAULT;
1301			break;
1302		}
1303		if (!ling.l_onoff) {
1304			sock_reset_flag(sk, SOCK_LINGER);
1305		} else {
1306			unsigned long t_sec = ling.l_linger;
1307
1308			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1309				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1310			else
1311				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1312			sock_set_flag(sk, SOCK_LINGER);
1313		}
1314		break;
1315
1316	case SO_BSDCOMPAT:
1317		break;
1318
1319	case SO_TIMESTAMP_OLD:
1320	case SO_TIMESTAMP_NEW:
1321	case SO_TIMESTAMPNS_OLD:
1322	case SO_TIMESTAMPNS_NEW:
1323		sock_set_timestamp(sk, optname, valbool);
1324		break;
1325
1326	case SO_TIMESTAMPING_NEW:
1327	case SO_TIMESTAMPING_OLD:
1328		if (optlen == sizeof(timestamping)) {
1329			if (copy_from_sockptr(&timestamping, optval,
1330					      sizeof(timestamping))) {
1331				ret = -EFAULT;
1332				break;
1333			}
1334		} else {
1335			memset(&timestamping, 0, sizeof(timestamping));
1336			timestamping.flags = val;
1337		}
1338		ret = sock_set_timestamping(sk, optname, timestamping);
1339		break;
1340
1341	case SO_RCVLOWAT:
1342		{
1343		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1344
1345		if (val < 0)
1346			val = INT_MAX;
1347		if (sock)
1348			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1349		if (set_rcvlowat)
1350			ret = set_rcvlowat(sk, val);
1351		else
1352			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1353		break;
1354		}
1355	case SO_RCVTIMEO_OLD:
1356	case SO_RCVTIMEO_NEW:
1357		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1358				       optlen, optname == SO_RCVTIMEO_OLD);
1359		break;
1360
1361	case SO_SNDTIMEO_OLD:
1362	case SO_SNDTIMEO_NEW:
1363		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1364				       optlen, optname == SO_SNDTIMEO_OLD);
1365		break;
1366
1367	case SO_ATTACH_FILTER: {
1368		struct sock_fprog fprog;
1369
1370		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1371		if (!ret)
1372			ret = sk_attach_filter(&fprog, sk);
1373		break;
1374	}
1375	case SO_ATTACH_BPF:
1376		ret = -EINVAL;
1377		if (optlen == sizeof(u32)) {
1378			u32 ufd;
1379
1380			ret = -EFAULT;
1381			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1382				break;
1383
1384			ret = sk_attach_bpf(ufd, sk);
1385		}
1386		break;
1387
1388	case SO_ATTACH_REUSEPORT_CBPF: {
1389		struct sock_fprog fprog;
1390
1391		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1392		if (!ret)
1393			ret = sk_reuseport_attach_filter(&fprog, sk);
1394		break;
1395	}
1396	case SO_ATTACH_REUSEPORT_EBPF:
1397		ret = -EINVAL;
1398		if (optlen == sizeof(u32)) {
1399			u32 ufd;
1400
1401			ret = -EFAULT;
1402			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1403				break;
1404
1405			ret = sk_reuseport_attach_bpf(ufd, sk);
1406		}
1407		break;
1408
1409	case SO_DETACH_REUSEPORT_BPF:
1410		ret = reuseport_detach_prog(sk);
1411		break;
1412
1413	case SO_DETACH_FILTER:
1414		ret = sk_detach_filter(sk);
1415		break;
1416
1417	case SO_LOCK_FILTER:
1418		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1419			ret = -EPERM;
1420		else
1421			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1422		break;
1423
1424	case SO_MARK:
1425		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1426		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1427			ret = -EPERM;
1428			break;
1429		}
1430
1431		__sock_set_mark(sk, val);
1432		break;
1433	case SO_RCVMARK:
1434		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1435		break;
1436
1437	case SO_RXQ_OVFL:
1438		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1439		break;
1440
1441	case SO_WIFI_STATUS:
1442		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1443		break;
1444
1445	case SO_NOFCS:
1446		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1447		break;
1448
1449	case SO_SELECT_ERR_QUEUE:
1450		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1451		break;
1452
1453
1454	case SO_INCOMING_CPU:
1455		reuseport_update_incoming_cpu(sk, val);
1456		break;
1457
1458	case SO_CNX_ADVICE:
1459		if (val == 1)
1460			dst_negative_advice(sk);
1461		break;
1462
1463	case SO_ZEROCOPY:
1464		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1465			if (!(sk_is_tcp(sk) ||
1466			      (sk->sk_type == SOCK_DGRAM &&
1467			       sk->sk_protocol == IPPROTO_UDP)))
1468				ret = -EOPNOTSUPP;
1469		} else if (sk->sk_family != PF_RDS) {
1470			ret = -EOPNOTSUPP;
1471		}
1472		if (!ret) {
1473			if (val < 0 || val > 1)
1474				ret = -EINVAL;
1475			else
1476				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1477		}
1478		break;
1479
1480	case SO_TXTIME:
1481		if (optlen != sizeof(struct sock_txtime)) {
1482			ret = -EINVAL;
1483			break;
1484		} else if (copy_from_sockptr(&sk_txtime, optval,
1485			   sizeof(struct sock_txtime))) {
1486			ret = -EFAULT;
1487			break;
1488		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1489			ret = -EINVAL;
1490			break;
1491		}
1492		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1493		 * scheduler has enough safe guards.
1494		 */
1495		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1496		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1497			ret = -EPERM;
1498			break;
1499		}
1500		sock_valbool_flag(sk, SOCK_TXTIME, true);
1501		sk->sk_clockid = sk_txtime.clockid;
1502		sk->sk_txtime_deadline_mode =
1503			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1504		sk->sk_txtime_report_errors =
1505			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1506		break;
1507
1508	case SO_BINDTOIFINDEX:
1509		ret = sock_bindtoindex_locked(sk, val);
1510		break;
1511
1512	case SO_BUF_LOCK:
1513		if (val & ~SOCK_BUF_LOCK_MASK) {
1514			ret = -EINVAL;
1515			break;
1516		}
1517		sk->sk_userlocks = val | (sk->sk_userlocks &
1518					  ~SOCK_BUF_LOCK_MASK);
1519		break;
1520
1521	case SO_RESERVE_MEM:
1522	{
1523		int delta;
1524
1525		if (val < 0) {
1526			ret = -EINVAL;
1527			break;
1528		}
1529
1530		delta = val - sk->sk_reserved_mem;
1531		if (delta < 0)
1532			sock_release_reserved_memory(sk, -delta);
1533		else
1534			ret = sock_reserve_memory(sk, delta);
1535		break;
1536	}
1537
1538	default:
1539		ret = -ENOPROTOOPT;
1540		break;
1541	}
1542	sockopt_release_sock(sk);
1543	return ret;
1544}
1545
1546int sock_setsockopt(struct socket *sock, int level, int optname,
1547		    sockptr_t optval, unsigned int optlen)
1548{
1549	return sk_setsockopt(sock->sk, level, optname,
1550			     optval, optlen);
1551}
1552EXPORT_SYMBOL(sock_setsockopt);
1553
1554static const struct cred *sk_get_peer_cred(struct sock *sk)
1555{
1556	const struct cred *cred;
1557
1558	spin_lock(&sk->sk_peer_lock);
1559	cred = get_cred(sk->sk_peer_cred);
1560	spin_unlock(&sk->sk_peer_lock);
1561
1562	return cred;
1563}
1564
1565static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1566			  struct ucred *ucred)
1567{
1568	ucred->pid = pid_vnr(pid);
1569	ucred->uid = ucred->gid = -1;
1570	if (cred) {
1571		struct user_namespace *current_ns = current_user_ns();
1572
1573		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1574		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1575	}
1576}
1577
1578static int groups_to_user(sockptr_t dst, const struct group_info *src)
1579{
1580	struct user_namespace *user_ns = current_user_ns();
1581	int i;
1582
1583	for (i = 0; i < src->ngroups; i++) {
1584		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1585
1586		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1587			return -EFAULT;
1588	}
1589
1590	return 0;
1591}
1592
1593int sk_getsockopt(struct sock *sk, int level, int optname,
1594		  sockptr_t optval, sockptr_t optlen)
1595{
1596	struct socket *sock = sk->sk_socket;
1597
1598	union {
1599		int val;
1600		u64 val64;
1601		unsigned long ulval;
1602		struct linger ling;
1603		struct old_timeval32 tm32;
1604		struct __kernel_old_timeval tm;
1605		struct  __kernel_sock_timeval stm;
1606		struct sock_txtime txtime;
1607		struct so_timestamping timestamping;
1608	} v;
1609
1610	int lv = sizeof(int);
1611	int len;
1612
1613	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1614		return -EFAULT;
1615	if (len < 0)
1616		return -EINVAL;
1617
1618	memset(&v, 0, sizeof(v));
1619
1620	switch (optname) {
1621	case SO_DEBUG:
1622		v.val = sock_flag(sk, SOCK_DBG);
1623		break;
1624
1625	case SO_DONTROUTE:
1626		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1627		break;
1628
1629	case SO_BROADCAST:
1630		v.val = sock_flag(sk, SOCK_BROADCAST);
1631		break;
1632
1633	case SO_SNDBUF:
1634		v.val = READ_ONCE(sk->sk_sndbuf);
1635		break;
1636
1637	case SO_RCVBUF:
1638		v.val = READ_ONCE(sk->sk_rcvbuf);
1639		break;
1640
1641	case SO_REUSEADDR:
1642		v.val = sk->sk_reuse;
1643		break;
1644
1645	case SO_REUSEPORT:
1646		v.val = sk->sk_reuseport;
1647		break;
1648
1649	case SO_KEEPALIVE:
1650		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1651		break;
1652
1653	case SO_TYPE:
1654		v.val = sk->sk_type;
1655		break;
1656
1657	case SO_PROTOCOL:
1658		v.val = sk->sk_protocol;
1659		break;
1660
1661	case SO_DOMAIN:
1662		v.val = sk->sk_family;
1663		break;
1664
1665	case SO_ERROR:
1666		v.val = -sock_error(sk);
1667		if (v.val == 0)
1668			v.val = xchg(&sk->sk_err_soft, 0);
1669		break;
1670
1671	case SO_OOBINLINE:
1672		v.val = sock_flag(sk, SOCK_URGINLINE);
1673		break;
1674
1675	case SO_NO_CHECK:
1676		v.val = sk->sk_no_check_tx;
1677		break;
1678
1679	case SO_PRIORITY:
1680		v.val = READ_ONCE(sk->sk_priority);
1681		break;
1682
1683	case SO_LINGER:
1684		lv		= sizeof(v.ling);
1685		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1686		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1687		break;
1688
1689	case SO_BSDCOMPAT:
1690		break;
1691
1692	case SO_TIMESTAMP_OLD:
1693		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1694				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1695				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1696		break;
1697
1698	case SO_TIMESTAMPNS_OLD:
1699		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1700		break;
1701
1702	case SO_TIMESTAMP_NEW:
1703		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1704		break;
1705
1706	case SO_TIMESTAMPNS_NEW:
1707		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1708		break;
1709
1710	case SO_TIMESTAMPING_OLD:
1711	case SO_TIMESTAMPING_NEW:
1712		lv = sizeof(v.timestamping);
1713		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1714		 * returning the flags when they were set through the same option.
1715		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1716		 */
1717		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1718			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1719			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1720		}
1721		break;
1722
1723	case SO_RCVTIMEO_OLD:
1724	case SO_RCVTIMEO_NEW:
1725		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1726				      SO_RCVTIMEO_OLD == optname);
1727		break;
1728
1729	case SO_SNDTIMEO_OLD:
1730	case SO_SNDTIMEO_NEW:
1731		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1732				      SO_SNDTIMEO_OLD == optname);
1733		break;
1734
1735	case SO_RCVLOWAT:
1736		v.val = READ_ONCE(sk->sk_rcvlowat);
1737		break;
1738
1739	case SO_SNDLOWAT:
1740		v.val = 1;
1741		break;
1742
1743	case SO_PASSCRED:
1744		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1745		break;
1746
1747	case SO_PASSPIDFD:
1748		v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1749		break;
1750
1751	case SO_PEERCRED:
1752	{
1753		struct ucred peercred;
1754		if (len > sizeof(peercred))
1755			len = sizeof(peercred);
1756
1757		spin_lock(&sk->sk_peer_lock);
1758		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1759		spin_unlock(&sk->sk_peer_lock);
1760
1761		if (copy_to_sockptr(optval, &peercred, len))
1762			return -EFAULT;
1763		goto lenout;
1764	}
1765
1766	case SO_PEERPIDFD:
1767	{
1768		struct pid *peer_pid;
1769		struct file *pidfd_file = NULL;
1770		int pidfd;
1771
1772		if (len > sizeof(pidfd))
1773			len = sizeof(pidfd);
1774
1775		spin_lock(&sk->sk_peer_lock);
1776		peer_pid = get_pid(sk->sk_peer_pid);
1777		spin_unlock(&sk->sk_peer_lock);
1778
1779		if (!peer_pid)
1780			return -ENODATA;
1781
1782		pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file);
1783		put_pid(peer_pid);
1784		if (pidfd < 0)
1785			return pidfd;
1786
1787		if (copy_to_sockptr(optval, &pidfd, len) ||
1788		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1789			put_unused_fd(pidfd);
1790			fput(pidfd_file);
1791
1792			return -EFAULT;
1793		}
1794
1795		fd_install(pidfd, pidfd_file);
1796		return 0;
1797	}
1798
1799	case SO_PEERGROUPS:
1800	{
1801		const struct cred *cred;
1802		int ret, n;
1803
1804		cred = sk_get_peer_cred(sk);
1805		if (!cred)
1806			return -ENODATA;
1807
1808		n = cred->group_info->ngroups;
1809		if (len < n * sizeof(gid_t)) {
1810			len = n * sizeof(gid_t);
1811			put_cred(cred);
1812			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1813		}
1814		len = n * sizeof(gid_t);
1815
1816		ret = groups_to_user(optval, cred->group_info);
1817		put_cred(cred);
1818		if (ret)
1819			return ret;
1820		goto lenout;
1821	}
1822
1823	case SO_PEERNAME:
1824	{
1825		struct sockaddr_storage address;
1826
1827		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1828		if (lv < 0)
1829			return -ENOTCONN;
1830		if (lv < len)
1831			return -EINVAL;
1832		if (copy_to_sockptr(optval, &address, len))
1833			return -EFAULT;
1834		goto lenout;
1835	}
1836
1837	/* Dubious BSD thing... Probably nobody even uses it, but
1838	 * the UNIX standard wants it for whatever reason... -DaveM
1839	 */
1840	case SO_ACCEPTCONN:
1841		v.val = sk->sk_state == TCP_LISTEN;
1842		break;
1843
1844	case SO_PASSSEC:
1845		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1846		break;
1847
1848	case SO_PEERSEC:
1849		return security_socket_getpeersec_stream(sock,
1850							 optval, optlen, len);
1851
1852	case SO_MARK:
1853		v.val = READ_ONCE(sk->sk_mark);
1854		break;
1855
1856	case SO_RCVMARK:
1857		v.val = sock_flag(sk, SOCK_RCVMARK);
1858		break;
1859
1860	case SO_RXQ_OVFL:
1861		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1862		break;
1863
1864	case SO_WIFI_STATUS:
1865		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1866		break;
1867
1868	case SO_PEEK_OFF:
1869		if (!READ_ONCE(sock->ops)->set_peek_off)
1870			return -EOPNOTSUPP;
1871
1872		v.val = READ_ONCE(sk->sk_peek_off);
1873		break;
1874	case SO_NOFCS:
1875		v.val = sock_flag(sk, SOCK_NOFCS);
1876		break;
1877
1878	case SO_BINDTODEVICE:
1879		return sock_getbindtodevice(sk, optval, optlen, len);
1880
1881	case SO_GET_FILTER:
1882		len = sk_get_filter(sk, optval, len);
1883		if (len < 0)
1884			return len;
1885
1886		goto lenout;
1887
1888	case SO_LOCK_FILTER:
1889		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1890		break;
1891
1892	case SO_BPF_EXTENSIONS:
1893		v.val = bpf_tell_extensions();
1894		break;
1895
1896	case SO_SELECT_ERR_QUEUE:
1897		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1898		break;
1899
1900#ifdef CONFIG_NET_RX_BUSY_POLL
1901	case SO_BUSY_POLL:
1902		v.val = READ_ONCE(sk->sk_ll_usec);
1903		break;
1904	case SO_PREFER_BUSY_POLL:
1905		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1906		break;
1907#endif
1908
1909	case SO_MAX_PACING_RATE:
1910		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
1911		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1912			lv = sizeof(v.ulval);
1913			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
1914		} else {
1915			/* 32bit version */
1916			v.val = min_t(unsigned long, ~0U,
1917				      READ_ONCE(sk->sk_max_pacing_rate));
1918		}
1919		break;
1920
1921	case SO_INCOMING_CPU:
1922		v.val = READ_ONCE(sk->sk_incoming_cpu);
1923		break;
1924
1925	case SO_MEMINFO:
1926	{
1927		u32 meminfo[SK_MEMINFO_VARS];
1928
1929		sk_get_meminfo(sk, meminfo);
1930
1931		len = min_t(unsigned int, len, sizeof(meminfo));
1932		if (copy_to_sockptr(optval, &meminfo, len))
1933			return -EFAULT;
1934
1935		goto lenout;
1936	}
1937
1938#ifdef CONFIG_NET_RX_BUSY_POLL
1939	case SO_INCOMING_NAPI_ID:
1940		v.val = READ_ONCE(sk->sk_napi_id);
1941
1942		/* aggregate non-NAPI IDs down to 0 */
1943		if (v.val < MIN_NAPI_ID)
1944			v.val = 0;
1945
1946		break;
1947#endif
1948
1949	case SO_COOKIE:
1950		lv = sizeof(u64);
1951		if (len < lv)
1952			return -EINVAL;
1953		v.val64 = sock_gen_cookie(sk);
1954		break;
1955
1956	case SO_ZEROCOPY:
1957		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1958		break;
1959
1960	case SO_TXTIME:
1961		lv = sizeof(v.txtime);
1962		v.txtime.clockid = sk->sk_clockid;
1963		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1964				  SOF_TXTIME_DEADLINE_MODE : 0;
1965		v.txtime.flags |= sk->sk_txtime_report_errors ?
1966				  SOF_TXTIME_REPORT_ERRORS : 0;
1967		break;
1968
1969	case SO_BINDTOIFINDEX:
1970		v.val = READ_ONCE(sk->sk_bound_dev_if);
1971		break;
1972
1973	case SO_NETNS_COOKIE:
1974		lv = sizeof(u64);
1975		if (len != lv)
1976			return -EINVAL;
1977		v.val64 = sock_net(sk)->net_cookie;
1978		break;
1979
1980	case SO_BUF_LOCK:
1981		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1982		break;
1983
1984	case SO_RESERVE_MEM:
1985		v.val = READ_ONCE(sk->sk_reserved_mem);
1986		break;
1987
1988	case SO_TXREHASH:
1989		/* Paired with WRITE_ONCE() in sk_setsockopt() */
1990		v.val = READ_ONCE(sk->sk_txrehash);
1991		break;
1992
1993	default:
1994		/* We implement the SO_SNDLOWAT etc to not be settable
1995		 * (1003.1g 7).
1996		 */
1997		return -ENOPROTOOPT;
1998	}
1999
2000	if (len > lv)
2001		len = lv;
2002	if (copy_to_sockptr(optval, &v, len))
2003		return -EFAULT;
2004lenout:
2005	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2006		return -EFAULT;
2007	return 0;
2008}
2009
2010/*
2011 * Initialize an sk_lock.
2012 *
2013 * (We also register the sk_lock with the lock validator.)
2014 */
2015static inline void sock_lock_init(struct sock *sk)
2016{
2017	if (sk->sk_kern_sock)
2018		sock_lock_init_class_and_name(
2019			sk,
2020			af_family_kern_slock_key_strings[sk->sk_family],
2021			af_family_kern_slock_keys + sk->sk_family,
2022			af_family_kern_key_strings[sk->sk_family],
2023			af_family_kern_keys + sk->sk_family);
2024	else
2025		sock_lock_init_class_and_name(
2026			sk,
2027			af_family_slock_key_strings[sk->sk_family],
2028			af_family_slock_keys + sk->sk_family,
2029			af_family_key_strings[sk->sk_family],
2030			af_family_keys + sk->sk_family);
2031}
2032
2033/*
2034 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2035 * even temporarly, because of RCU lookups. sk_node should also be left as is.
2036 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2037 */
2038static void sock_copy(struct sock *nsk, const struct sock *osk)
2039{
2040	const struct proto *prot = READ_ONCE(osk->sk_prot);
2041#ifdef CONFIG_SECURITY_NETWORK
2042	void *sptr = nsk->sk_security;
2043#endif
2044
2045	/* If we move sk_tx_queue_mapping out of the private section,
2046	 * we must check if sk_tx_queue_clear() is called after
2047	 * sock_copy() in sk_clone_lock().
2048	 */
2049	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2050		     offsetof(struct sock, sk_dontcopy_begin) ||
2051		     offsetof(struct sock, sk_tx_queue_mapping) >=
2052		     offsetof(struct sock, sk_dontcopy_end));
2053
2054	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2055
2056	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2057		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2058		      /* alloc is larger than struct, see sk_prot_alloc() */);
2059
2060#ifdef CONFIG_SECURITY_NETWORK
2061	nsk->sk_security = sptr;
2062	security_sk_clone(osk, nsk);
2063#endif
2064}
2065
2066static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2067		int family)
2068{
2069	struct sock *sk;
2070	struct kmem_cache *slab;
2071
2072	slab = prot->slab;
2073	if (slab != NULL) {
2074		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2075		if (!sk)
2076			return sk;
2077		if (want_init_on_alloc(priority))
2078			sk_prot_clear_nulls(sk, prot->obj_size);
2079	} else
2080		sk = kmalloc(prot->obj_size, priority);
2081
2082	if (sk != NULL) {
2083		if (security_sk_alloc(sk, family, priority))
2084			goto out_free;
2085
2086		if (!try_module_get(prot->owner))
2087			goto out_free_sec;
2088	}
2089
2090	return sk;
2091
2092out_free_sec:
2093	security_sk_free(sk);
2094out_free:
2095	if (slab != NULL)
2096		kmem_cache_free(slab, sk);
2097	else
2098		kfree(sk);
2099	return NULL;
2100}
2101
2102static void sk_prot_free(struct proto *prot, struct sock *sk)
2103{
2104	struct kmem_cache *slab;
2105	struct module *owner;
2106
2107	owner = prot->owner;
2108	slab = prot->slab;
2109
2110	cgroup_sk_free(&sk->sk_cgrp_data);
2111	mem_cgroup_sk_free(sk);
2112	security_sk_free(sk);
2113	if (slab != NULL)
2114		kmem_cache_free(slab, sk);
2115	else
2116		kfree(sk);
2117	module_put(owner);
2118}
2119
2120/**
2121 *	sk_alloc - All socket objects are allocated here
2122 *	@net: the applicable net namespace
2123 *	@family: protocol family
2124 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2125 *	@prot: struct proto associated with this new sock instance
2126 *	@kern: is this to be a kernel socket?
2127 */
2128struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2129		      struct proto *prot, int kern)
2130{
2131	struct sock *sk;
2132
2133	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2134	if (sk) {
2135		sk->sk_family = family;
2136		/*
2137		 * See comment in struct sock definition to understand
2138		 * why we need sk_prot_creator -acme
2139		 */
2140		sk->sk_prot = sk->sk_prot_creator = prot;
2141		sk->sk_kern_sock = kern;
2142		sock_lock_init(sk);
2143		sk->sk_net_refcnt = kern ? 0 : 1;
2144		if (likely(sk->sk_net_refcnt)) {
2145			get_net_track(net, &sk->ns_tracker, priority);
2146			sock_inuse_add(net, 1);
2147		} else {
2148			__netns_tracker_alloc(net, &sk->ns_tracker,
2149					      false, priority);
2150		}
2151
2152		sock_net_set(sk, net);
2153		refcount_set(&sk->sk_wmem_alloc, 1);
2154
2155		mem_cgroup_sk_alloc(sk);
2156		cgroup_sk_alloc(&sk->sk_cgrp_data);
2157		sock_update_classid(&sk->sk_cgrp_data);
2158		sock_update_netprioidx(&sk->sk_cgrp_data);
2159		sk_tx_queue_clear(sk);
2160	}
2161
2162	return sk;
2163}
2164EXPORT_SYMBOL(sk_alloc);
2165
2166/* Sockets having SOCK_RCU_FREE will call this function after one RCU
2167 * grace period. This is the case for UDP sockets and TCP listeners.
2168 */
2169static void __sk_destruct(struct rcu_head *head)
2170{
2171	struct sock *sk = container_of(head, struct sock, sk_rcu);
2172	struct sk_filter *filter;
2173
2174	if (sk->sk_destruct)
2175		sk->sk_destruct(sk);
2176
2177	filter = rcu_dereference_check(sk->sk_filter,
2178				       refcount_read(&sk->sk_wmem_alloc) == 0);
2179	if (filter) {
2180		sk_filter_uncharge(sk, filter);
2181		RCU_INIT_POINTER(sk->sk_filter, NULL);
2182	}
2183
2184	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2185
2186#ifdef CONFIG_BPF_SYSCALL
2187	bpf_sk_storage_free(sk);
2188#endif
2189
2190	if (atomic_read(&sk->sk_omem_alloc))
2191		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2192			 __func__, atomic_read(&sk->sk_omem_alloc));
2193
2194	if (sk->sk_frag.page) {
2195		put_page(sk->sk_frag.page);
2196		sk->sk_frag.page = NULL;
2197	}
2198
2199	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2200	put_cred(sk->sk_peer_cred);
2201	put_pid(sk->sk_peer_pid);
2202
2203	if (likely(sk->sk_net_refcnt))
2204		put_net_track(sock_net(sk), &sk->ns_tracker);
2205	else
2206		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2207
2208	sk_prot_free(sk->sk_prot_creator, sk);
2209}
2210
2211void sk_destruct(struct sock *sk)
2212{
2213	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2214
2215	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2216		reuseport_detach_sock(sk);
2217		use_call_rcu = true;
2218	}
2219
2220	if (use_call_rcu)
2221		call_rcu(&sk->sk_rcu, __sk_destruct);
2222	else
2223		__sk_destruct(&sk->sk_rcu);
2224}
2225
2226static void __sk_free(struct sock *sk)
2227{
2228	if (likely(sk->sk_net_refcnt))
2229		sock_inuse_add(sock_net(sk), -1);
2230
2231	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2232		sock_diag_broadcast_destroy(sk);
2233	else
2234		sk_destruct(sk);
2235}
2236
2237void sk_free(struct sock *sk)
2238{
2239	/*
2240	 * We subtract one from sk_wmem_alloc and can know if
2241	 * some packets are still in some tx queue.
2242	 * If not null, sock_wfree() will call __sk_free(sk) later
2243	 */
2244	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2245		__sk_free(sk);
2246}
2247EXPORT_SYMBOL(sk_free);
2248
2249static void sk_init_common(struct sock *sk)
2250{
2251	skb_queue_head_init(&sk->sk_receive_queue);
2252	skb_queue_head_init(&sk->sk_write_queue);
2253	skb_queue_head_init(&sk->sk_error_queue);
2254
2255	rwlock_init(&sk->sk_callback_lock);
2256	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2257			af_rlock_keys + sk->sk_family,
2258			af_family_rlock_key_strings[sk->sk_family]);
2259	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2260			af_wlock_keys + sk->sk_family,
2261			af_family_wlock_key_strings[sk->sk_family]);
2262	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2263			af_elock_keys + sk->sk_family,
2264			af_family_elock_key_strings[sk->sk_family]);
2265	lockdep_set_class_and_name(&sk->sk_callback_lock,
2266			af_callback_keys + sk->sk_family,
2267			af_family_clock_key_strings[sk->sk_family]);
2268}
2269
2270/**
2271 *	sk_clone_lock - clone a socket, and lock its clone
2272 *	@sk: the socket to clone
2273 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2274 *
2275 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2276 */
2277struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2278{
2279	struct proto *prot = READ_ONCE(sk->sk_prot);
2280	struct sk_filter *filter;
2281	bool is_charged = true;
2282	struct sock *newsk;
2283
2284	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2285	if (!newsk)
2286		goto out;
2287
2288	sock_copy(newsk, sk);
2289
2290	newsk->sk_prot_creator = prot;
2291
2292	/* SANITY */
2293	if (likely(newsk->sk_net_refcnt)) {
2294		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2295		sock_inuse_add(sock_net(newsk), 1);
2296	} else {
2297		/* Kernel sockets are not elevating the struct net refcount.
2298		 * Instead, use a tracker to more easily detect if a layer
2299		 * is not properly dismantling its kernel sockets at netns
2300		 * destroy time.
2301		 */
2302		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2303				      false, priority);
2304	}
2305	sk_node_init(&newsk->sk_node);
2306	sock_lock_init(newsk);
2307	bh_lock_sock(newsk);
2308	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2309	newsk->sk_backlog.len = 0;
2310
2311	atomic_set(&newsk->sk_rmem_alloc, 0);
2312
2313	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2314	refcount_set(&newsk->sk_wmem_alloc, 1);
2315
2316	atomic_set(&newsk->sk_omem_alloc, 0);
2317	sk_init_common(newsk);
2318
2319	newsk->sk_dst_cache	= NULL;
2320	newsk->sk_dst_pending_confirm = 0;
2321	newsk->sk_wmem_queued	= 0;
2322	newsk->sk_forward_alloc = 0;
2323	newsk->sk_reserved_mem  = 0;
2324	atomic_set(&newsk->sk_drops, 0);
2325	newsk->sk_send_head	= NULL;
2326	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2327	atomic_set(&newsk->sk_zckey, 0);
2328
2329	sock_reset_flag(newsk, SOCK_DONE);
2330
2331	/* sk->sk_memcg will be populated at accept() time */
2332	newsk->sk_memcg = NULL;
2333
2334	cgroup_sk_clone(&newsk->sk_cgrp_data);
2335
2336	rcu_read_lock();
2337	filter = rcu_dereference(sk->sk_filter);
2338	if (filter != NULL)
2339		/* though it's an empty new sock, the charging may fail
2340		 * if sysctl_optmem_max was changed between creation of
2341		 * original socket and cloning
2342		 */
2343		is_charged = sk_filter_charge(newsk, filter);
2344	RCU_INIT_POINTER(newsk->sk_filter, filter);
2345	rcu_read_unlock();
2346
2347	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2348		/* We need to make sure that we don't uncharge the new
2349		 * socket if we couldn't charge it in the first place
2350		 * as otherwise we uncharge the parent's filter.
2351		 */
2352		if (!is_charged)
2353			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2354		sk_free_unlock_clone(newsk);
2355		newsk = NULL;
2356		goto out;
2357	}
2358	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2359
2360	if (bpf_sk_storage_clone(sk, newsk)) {
2361		sk_free_unlock_clone(newsk);
2362		newsk = NULL;
2363		goto out;
2364	}
2365
2366	/* Clear sk_user_data if parent had the pointer tagged
2367	 * as not suitable for copying when cloning.
2368	 */
2369	if (sk_user_data_is_nocopy(newsk))
2370		newsk->sk_user_data = NULL;
2371
2372	newsk->sk_err	   = 0;
2373	newsk->sk_err_soft = 0;
2374	newsk->sk_priority = 0;
2375	newsk->sk_incoming_cpu = raw_smp_processor_id();
2376
2377	/* Before updating sk_refcnt, we must commit prior changes to memory
2378	 * (Documentation/RCU/rculist_nulls.rst for details)
2379	 */
2380	smp_wmb();
2381	refcount_set(&newsk->sk_refcnt, 2);
2382
2383	sk_set_socket(newsk, NULL);
2384	sk_tx_queue_clear(newsk);
2385	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2386
2387	if (newsk->sk_prot->sockets_allocated)
2388		sk_sockets_allocated_inc(newsk);
2389
2390	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2391		net_enable_timestamp();
2392out:
2393	return newsk;
2394}
2395EXPORT_SYMBOL_GPL(sk_clone_lock);
2396
2397void sk_free_unlock_clone(struct sock *sk)
2398{
2399	/* It is still raw copy of parent, so invalidate
2400	 * destructor and make plain sk_free() */
2401	sk->sk_destruct = NULL;
2402	bh_unlock_sock(sk);
2403	sk_free(sk);
2404}
2405EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2406
2407static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2408{
2409	bool is_ipv6 = false;
2410	u32 max_size;
2411
2412#if IS_ENABLED(CONFIG_IPV6)
2413	is_ipv6 = (sk->sk_family == AF_INET6 &&
2414		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2415#endif
2416	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2417	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2418			READ_ONCE(dst->dev->gso_ipv4_max_size);
2419	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2420		max_size = GSO_LEGACY_MAX_SIZE;
2421
2422	return max_size - (MAX_TCP_HEADER + 1);
2423}
2424
2425void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2426{
2427	u32 max_segs = 1;
2428
2429	sk->sk_route_caps = dst->dev->features;
2430	if (sk_is_tcp(sk))
2431		sk->sk_route_caps |= NETIF_F_GSO;
2432	if (sk->sk_route_caps & NETIF_F_GSO)
2433		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2434	if (unlikely(sk->sk_gso_disabled))
2435		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2436	if (sk_can_gso(sk)) {
2437		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2438			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2439		} else {
2440			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2441			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2442			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2443			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2444		}
2445	}
2446	sk->sk_gso_max_segs = max_segs;
2447	sk_dst_set(sk, dst);
2448}
2449EXPORT_SYMBOL_GPL(sk_setup_caps);
2450
2451/*
2452 *	Simple resource managers for sockets.
2453 */
2454
2455
2456/*
2457 * Write buffer destructor automatically called from kfree_skb.
2458 */
2459void sock_wfree(struct sk_buff *skb)
2460{
2461	struct sock *sk = skb->sk;
2462	unsigned int len = skb->truesize;
2463	bool free;
2464
2465	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2466		if (sock_flag(sk, SOCK_RCU_FREE) &&
2467		    sk->sk_write_space == sock_def_write_space) {
2468			rcu_read_lock();
2469			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2470			sock_def_write_space_wfree(sk);
2471			rcu_read_unlock();
2472			if (unlikely(free))
2473				__sk_free(sk);
2474			return;
2475		}
2476
2477		/*
2478		 * Keep a reference on sk_wmem_alloc, this will be released
2479		 * after sk_write_space() call
2480		 */
2481		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2482		sk->sk_write_space(sk);
2483		len = 1;
2484	}
2485	/*
2486	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2487	 * could not do because of in-flight packets
2488	 */
2489	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2490		__sk_free(sk);
2491}
2492EXPORT_SYMBOL(sock_wfree);
2493
2494/* This variant of sock_wfree() is used by TCP,
2495 * since it sets SOCK_USE_WRITE_QUEUE.
2496 */
2497void __sock_wfree(struct sk_buff *skb)
2498{
2499	struct sock *sk = skb->sk;
2500
2501	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2502		__sk_free(sk);
2503}
2504
2505void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2506{
2507	skb_orphan(skb);
2508	skb->sk = sk;
2509#ifdef CONFIG_INET
2510	if (unlikely(!sk_fullsock(sk))) {
2511		skb->destructor = sock_edemux;
2512		sock_hold(sk);
2513		return;
2514	}
2515#endif
2516	skb->destructor = sock_wfree;
2517	skb_set_hash_from_sk(skb, sk);
2518	/*
2519	 * We used to take a refcount on sk, but following operation
2520	 * is enough to guarantee sk_free() wont free this sock until
2521	 * all in-flight packets are completed
2522	 */
2523	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2524}
2525EXPORT_SYMBOL(skb_set_owner_w);
2526
2527static bool can_skb_orphan_partial(const struct sk_buff *skb)
2528{
2529#ifdef CONFIG_TLS_DEVICE
2530	/* Drivers depend on in-order delivery for crypto offload,
2531	 * partial orphan breaks out-of-order-OK logic.
2532	 */
2533	if (skb->decrypted)
2534		return false;
2535#endif
2536	return (skb->destructor == sock_wfree ||
2537		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2538}
2539
2540/* This helper is used by netem, as it can hold packets in its
2541 * delay queue. We want to allow the owner socket to send more
2542 * packets, as if they were already TX completed by a typical driver.
2543 * But we also want to keep skb->sk set because some packet schedulers
2544 * rely on it (sch_fq for example).
2545 */
2546void skb_orphan_partial(struct sk_buff *skb)
2547{
2548	if (skb_is_tcp_pure_ack(skb))
2549		return;
2550
2551	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2552		return;
2553
2554	skb_orphan(skb);
2555}
2556EXPORT_SYMBOL(skb_orphan_partial);
2557
2558/*
2559 * Read buffer destructor automatically called from kfree_skb.
2560 */
2561void sock_rfree(struct sk_buff *skb)
2562{
2563	struct sock *sk = skb->sk;
2564	unsigned int len = skb->truesize;
2565
2566	atomic_sub(len, &sk->sk_rmem_alloc);
2567	sk_mem_uncharge(sk, len);
2568}
2569EXPORT_SYMBOL(sock_rfree);
2570
2571/*
2572 * Buffer destructor for skbs that are not used directly in read or write
2573 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2574 */
2575void sock_efree(struct sk_buff *skb)
2576{
2577	sock_put(skb->sk);
2578}
2579EXPORT_SYMBOL(sock_efree);
2580
2581/* Buffer destructor for prefetch/receive path where reference count may
2582 * not be held, e.g. for listen sockets.
2583 */
2584#ifdef CONFIG_INET
2585void sock_pfree(struct sk_buff *skb)
2586{
2587	struct sock *sk = skb->sk;
2588
2589	if (!sk_is_refcounted(sk))
2590		return;
2591
2592	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2593		inet_reqsk(sk)->rsk_listener = NULL;
2594		reqsk_free(inet_reqsk(sk));
2595		return;
2596	}
2597
2598	sock_gen_put(sk);
2599}
2600EXPORT_SYMBOL(sock_pfree);
2601#endif /* CONFIG_INET */
2602
2603kuid_t sock_i_uid(struct sock *sk)
2604{
2605	kuid_t uid;
2606
2607	read_lock_bh(&sk->sk_callback_lock);
2608	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2609	read_unlock_bh(&sk->sk_callback_lock);
2610	return uid;
2611}
2612EXPORT_SYMBOL(sock_i_uid);
2613
2614unsigned long __sock_i_ino(struct sock *sk)
2615{
2616	unsigned long ino;
2617
2618	read_lock(&sk->sk_callback_lock);
2619	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2620	read_unlock(&sk->sk_callback_lock);
2621	return ino;
2622}
2623EXPORT_SYMBOL(__sock_i_ino);
2624
2625unsigned long sock_i_ino(struct sock *sk)
2626{
2627	unsigned long ino;
2628
2629	local_bh_disable();
2630	ino = __sock_i_ino(sk);
2631	local_bh_enable();
2632	return ino;
2633}
2634EXPORT_SYMBOL(sock_i_ino);
2635
2636/*
2637 * Allocate a skb from the socket's send buffer.
2638 */
2639struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2640			     gfp_t priority)
2641{
2642	if (force ||
2643	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2644		struct sk_buff *skb = alloc_skb(size, priority);
2645
2646		if (skb) {
2647			skb_set_owner_w(skb, sk);
2648			return skb;
2649		}
2650	}
2651	return NULL;
2652}
2653EXPORT_SYMBOL(sock_wmalloc);
2654
2655static void sock_ofree(struct sk_buff *skb)
2656{
2657	struct sock *sk = skb->sk;
2658
2659	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2660}
2661
2662struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2663			     gfp_t priority)
2664{
2665	struct sk_buff *skb;
2666
2667	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2668	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2669	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2670		return NULL;
2671
2672	skb = alloc_skb(size, priority);
2673	if (!skb)
2674		return NULL;
2675
2676	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2677	skb->sk = sk;
2678	skb->destructor = sock_ofree;
2679	return skb;
2680}
2681
2682/*
2683 * Allocate a memory block from the socket's option memory buffer.
2684 */
2685void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2686{
2687	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2688
2689	if ((unsigned int)size <= optmem_max &&
2690	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2691		void *mem;
2692		/* First do the add, to avoid the race if kmalloc
2693		 * might sleep.
2694		 */
2695		atomic_add(size, &sk->sk_omem_alloc);
2696		mem = kmalloc(size, priority);
2697		if (mem)
2698			return mem;
2699		atomic_sub(size, &sk->sk_omem_alloc);
2700	}
2701	return NULL;
2702}
2703EXPORT_SYMBOL(sock_kmalloc);
2704
2705/* Free an option memory block. Note, we actually want the inline
2706 * here as this allows gcc to detect the nullify and fold away the
2707 * condition entirely.
2708 */
2709static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2710				  const bool nullify)
2711{
2712	if (WARN_ON_ONCE(!mem))
2713		return;
2714	if (nullify)
2715		kfree_sensitive(mem);
2716	else
2717		kfree(mem);
2718	atomic_sub(size, &sk->sk_omem_alloc);
2719}
2720
2721void sock_kfree_s(struct sock *sk, void *mem, int size)
2722{
2723	__sock_kfree_s(sk, mem, size, false);
2724}
2725EXPORT_SYMBOL(sock_kfree_s);
2726
2727void sock_kzfree_s(struct sock *sk, void *mem, int size)
2728{
2729	__sock_kfree_s(sk, mem, size, true);
2730}
2731EXPORT_SYMBOL(sock_kzfree_s);
2732
2733/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2734   I think, these locks should be removed for datagram sockets.
2735 */
2736static long sock_wait_for_wmem(struct sock *sk, long timeo)
2737{
2738	DEFINE_WAIT(wait);
2739
2740	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2741	for (;;) {
2742		if (!timeo)
2743			break;
2744		if (signal_pending(current))
2745			break;
2746		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2747		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2748		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2749			break;
2750		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2751			break;
2752		if (READ_ONCE(sk->sk_err))
2753			break;
2754		timeo = schedule_timeout(timeo);
2755	}
2756	finish_wait(sk_sleep(sk), &wait);
2757	return timeo;
2758}
2759
2760
2761/*
2762 *	Generic send/receive buffer handlers
2763 */
2764
2765struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2766				     unsigned long data_len, int noblock,
2767				     int *errcode, int max_page_order)
2768{
2769	struct sk_buff *skb;
2770	long timeo;
2771	int err;
2772
2773	timeo = sock_sndtimeo(sk, noblock);
2774	for (;;) {
2775		err = sock_error(sk);
2776		if (err != 0)
2777			goto failure;
2778
2779		err = -EPIPE;
2780		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2781			goto failure;
2782
2783		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2784			break;
2785
2786		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2787		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2788		err = -EAGAIN;
2789		if (!timeo)
2790			goto failure;
2791		if (signal_pending(current))
2792			goto interrupted;
2793		timeo = sock_wait_for_wmem(sk, timeo);
2794	}
2795	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2796				   errcode, sk->sk_allocation);
2797	if (skb)
2798		skb_set_owner_w(skb, sk);
2799	return skb;
2800
2801interrupted:
2802	err = sock_intr_errno(timeo);
2803failure:
2804	*errcode = err;
2805	return NULL;
2806}
2807EXPORT_SYMBOL(sock_alloc_send_pskb);
2808
2809int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2810		     struct sockcm_cookie *sockc)
2811{
2812	u32 tsflags;
2813
2814	switch (cmsg->cmsg_type) {
2815	case SO_MARK:
2816		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2817		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2818			return -EPERM;
2819		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2820			return -EINVAL;
2821		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2822		break;
2823	case SO_TIMESTAMPING_OLD:
2824	case SO_TIMESTAMPING_NEW:
2825		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2826			return -EINVAL;
2827
2828		tsflags = *(u32 *)CMSG_DATA(cmsg);
2829		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2830			return -EINVAL;
2831
2832		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2833		sockc->tsflags |= tsflags;
2834		break;
2835	case SCM_TXTIME:
2836		if (!sock_flag(sk, SOCK_TXTIME))
2837			return -EINVAL;
2838		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2839			return -EINVAL;
2840		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2841		break;
2842	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2843	case SCM_RIGHTS:
2844	case SCM_CREDENTIALS:
2845		break;
2846	default:
2847		return -EINVAL;
2848	}
2849	return 0;
2850}
2851EXPORT_SYMBOL(__sock_cmsg_send);
2852
2853int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2854		   struct sockcm_cookie *sockc)
2855{
2856	struct cmsghdr *cmsg;
2857	int ret;
2858
2859	for_each_cmsghdr(cmsg, msg) {
2860		if (!CMSG_OK(msg, cmsg))
2861			return -EINVAL;
2862		if (cmsg->cmsg_level != SOL_SOCKET)
2863			continue;
2864		ret = __sock_cmsg_send(sk, cmsg, sockc);
2865		if (ret)
2866			return ret;
2867	}
2868	return 0;
2869}
2870EXPORT_SYMBOL(sock_cmsg_send);
2871
2872static void sk_enter_memory_pressure(struct sock *sk)
2873{
2874	if (!sk->sk_prot->enter_memory_pressure)
2875		return;
2876
2877	sk->sk_prot->enter_memory_pressure(sk);
2878}
2879
2880static void sk_leave_memory_pressure(struct sock *sk)
2881{
2882	if (sk->sk_prot->leave_memory_pressure) {
2883		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2884				     tcp_leave_memory_pressure, sk);
2885	} else {
2886		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2887
2888		if (memory_pressure && READ_ONCE(*memory_pressure))
2889			WRITE_ONCE(*memory_pressure, 0);
2890	}
2891}
2892
2893DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2894
2895/**
2896 * skb_page_frag_refill - check that a page_frag contains enough room
2897 * @sz: minimum size of the fragment we want to get
2898 * @pfrag: pointer to page_frag
2899 * @gfp: priority for memory allocation
2900 *
2901 * Note: While this allocator tries to use high order pages, there is
2902 * no guarantee that allocations succeed. Therefore, @sz MUST be
2903 * less or equal than PAGE_SIZE.
2904 */
2905bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2906{
2907	if (pfrag->page) {
2908		if (page_ref_count(pfrag->page) == 1) {
2909			pfrag->offset = 0;
2910			return true;
2911		}
2912		if (pfrag->offset + sz <= pfrag->size)
2913			return true;
2914		put_page(pfrag->page);
2915	}
2916
2917	pfrag->offset = 0;
2918	if (SKB_FRAG_PAGE_ORDER &&
2919	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2920		/* Avoid direct reclaim but allow kswapd to wake */
2921		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2922					  __GFP_COMP | __GFP_NOWARN |
2923					  __GFP_NORETRY,
2924					  SKB_FRAG_PAGE_ORDER);
2925		if (likely(pfrag->page)) {
2926			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2927			return true;
2928		}
2929	}
2930	pfrag->page = alloc_page(gfp);
2931	if (likely(pfrag->page)) {
2932		pfrag->size = PAGE_SIZE;
2933		return true;
2934	}
2935	return false;
2936}
2937EXPORT_SYMBOL(skb_page_frag_refill);
2938
2939bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2940{
2941	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2942		return true;
2943
2944	sk_enter_memory_pressure(sk);
2945	sk_stream_moderate_sndbuf(sk);
2946	return false;
2947}
2948EXPORT_SYMBOL(sk_page_frag_refill);
2949
2950void __lock_sock(struct sock *sk)
2951	__releases(&sk->sk_lock.slock)
2952	__acquires(&sk->sk_lock.slock)
2953{
2954	DEFINE_WAIT(wait);
2955
2956	for (;;) {
2957		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2958					TASK_UNINTERRUPTIBLE);
2959		spin_unlock_bh(&sk->sk_lock.slock);
2960		schedule();
2961		spin_lock_bh(&sk->sk_lock.slock);
2962		if (!sock_owned_by_user(sk))
2963			break;
2964	}
2965	finish_wait(&sk->sk_lock.wq, &wait);
2966}
2967
2968void __release_sock(struct sock *sk)
2969	__releases(&sk->sk_lock.slock)
2970	__acquires(&sk->sk_lock.slock)
2971{
2972	struct sk_buff *skb, *next;
2973
2974	while ((skb = sk->sk_backlog.head) != NULL) {
2975		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2976
2977		spin_unlock_bh(&sk->sk_lock.slock);
2978
2979		do {
2980			next = skb->next;
2981			prefetch(next);
2982			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2983			skb_mark_not_on_list(skb);
2984			sk_backlog_rcv(sk, skb);
2985
2986			cond_resched();
2987
2988			skb = next;
2989		} while (skb != NULL);
2990
2991		spin_lock_bh(&sk->sk_lock.slock);
2992	}
2993
2994	/*
2995	 * Doing the zeroing here guarantee we can not loop forever
2996	 * while a wild producer attempts to flood us.
2997	 */
2998	sk->sk_backlog.len = 0;
2999}
3000
3001void __sk_flush_backlog(struct sock *sk)
3002{
3003	spin_lock_bh(&sk->sk_lock.slock);
3004	__release_sock(sk);
3005
3006	if (sk->sk_prot->release_cb)
3007		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3008				     tcp_release_cb, sk);
3009
3010	spin_unlock_bh(&sk->sk_lock.slock);
3011}
3012EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3013
3014/**
3015 * sk_wait_data - wait for data to arrive at sk_receive_queue
3016 * @sk:    sock to wait on
3017 * @timeo: for how long
3018 * @skb:   last skb seen on sk_receive_queue
3019 *
3020 * Now socket state including sk->sk_err is changed only under lock,
3021 * hence we may omit checks after joining wait queue.
3022 * We check receive queue before schedule() only as optimization;
3023 * it is very likely that release_sock() added new data.
3024 */
3025int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3026{
3027	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3028	int rc;
3029
3030	add_wait_queue(sk_sleep(sk), &wait);
3031	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3032	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3033	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3034	remove_wait_queue(sk_sleep(sk), &wait);
3035	return rc;
3036}
3037EXPORT_SYMBOL(sk_wait_data);
3038
3039/**
3040 *	__sk_mem_raise_allocated - increase memory_allocated
3041 *	@sk: socket
3042 *	@size: memory size to allocate
3043 *	@amt: pages to allocate
3044 *	@kind: allocation type
3045 *
3046 *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3047 *
3048 *	Unlike the globally shared limits among the sockets under same protocol,
3049 *	consuming the budget of a memcg won't have direct effect on other ones.
3050 *	So be optimistic about memcg's tolerance, and leave the callers to decide
3051 *	whether or not to raise allocated through sk_under_memory_pressure() or
3052 *	its variants.
3053 */
3054int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3055{
3056	struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3057	struct proto *prot = sk->sk_prot;
3058	bool charged = false;
3059	long allocated;
3060
3061	sk_memory_allocated_add(sk, amt);
3062	allocated = sk_memory_allocated(sk);
3063
3064	if (memcg) {
3065		if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3066			goto suppress_allocation;
3067		charged = true;
3068	}
3069
3070	/* Under limit. */
3071	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3072		sk_leave_memory_pressure(sk);
3073		return 1;
3074	}
3075
3076	/* Under pressure. */
3077	if (allocated > sk_prot_mem_limits(sk, 1))
3078		sk_enter_memory_pressure(sk);
3079
3080	/* Over hard limit. */
3081	if (allocated > sk_prot_mem_limits(sk, 2))
3082		goto suppress_allocation;
3083
3084	/* Guarantee minimum buffer size under pressure (either global
3085	 * or memcg) to make sure features described in RFC 7323 (TCP
3086	 * Extensions for High Performance) work properly.
3087	 *
3088	 * This rule does NOT stand when exceeds global or memcg's hard
3089	 * limit, or else a DoS attack can be taken place by spawning
3090	 * lots of sockets whose usage are under minimum buffer size.
3091	 */
3092	if (kind == SK_MEM_RECV) {
3093		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3094			return 1;
3095
3096	} else { /* SK_MEM_SEND */
3097		int wmem0 = sk_get_wmem0(sk, prot);
3098
3099		if (sk->sk_type == SOCK_STREAM) {
3100			if (sk->sk_wmem_queued < wmem0)
3101				return 1;
3102		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3103				return 1;
3104		}
3105	}
3106
3107	if (sk_has_memory_pressure(sk)) {
3108		u64 alloc;
3109
3110		/* The following 'average' heuristic is within the
3111		 * scope of global accounting, so it only makes
3112		 * sense for global memory pressure.
3113		 */
3114		if (!sk_under_global_memory_pressure(sk))
3115			return 1;
3116
3117		/* Try to be fair among all the sockets under global
3118		 * pressure by allowing the ones that below average
3119		 * usage to raise.
3120		 */
3121		alloc = sk_sockets_allocated_read_positive(sk);
3122		if (sk_prot_mem_limits(sk, 2) > alloc *
3123		    sk_mem_pages(sk->sk_wmem_queued +
3124				 atomic_read(&sk->sk_rmem_alloc) +
3125				 sk->sk_forward_alloc))
3126			return 1;
3127	}
3128
3129suppress_allocation:
3130
3131	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3132		sk_stream_moderate_sndbuf(sk);
3133
3134		/* Fail only if socket is _under_ its sndbuf.
3135		 * In this case we cannot block, so that we have to fail.
3136		 */
3137		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3138			/* Force charge with __GFP_NOFAIL */
3139			if (memcg && !charged) {
3140				mem_cgroup_charge_skmem(memcg, amt,
3141					gfp_memcg_charge() | __GFP_NOFAIL);
3142			}
3143			return 1;
3144		}
3145	}
3146
3147	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3148		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3149
3150	sk_memory_allocated_sub(sk, amt);
3151
3152	if (charged)
3153		mem_cgroup_uncharge_skmem(memcg, amt);
3154
3155	return 0;
3156}
3157
3158/**
3159 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3160 *	@sk: socket
3161 *	@size: memory size to allocate
3162 *	@kind: allocation type
3163 *
3164 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3165 *	rmem allocation. This function assumes that protocols which have
3166 *	memory_pressure use sk_wmem_queued as write buffer accounting.
3167 */
3168int __sk_mem_schedule(struct sock *sk, int size, int kind)
3169{
3170	int ret, amt = sk_mem_pages(size);
3171
3172	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3173	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3174	if (!ret)
3175		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3176	return ret;
3177}
3178EXPORT_SYMBOL(__sk_mem_schedule);
3179
3180/**
3181 *	__sk_mem_reduce_allocated - reclaim memory_allocated
3182 *	@sk: socket
3183 *	@amount: number of quanta
3184 *
3185 *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3186 */
3187void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3188{
3189	sk_memory_allocated_sub(sk, amount);
3190
3191	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3192		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3193
3194	if (sk_under_global_memory_pressure(sk) &&
3195	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3196		sk_leave_memory_pressure(sk);
3197}
3198
3199/**
3200 *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3201 *	@sk: socket
3202 *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3203 */
3204void __sk_mem_reclaim(struct sock *sk, int amount)
3205{
3206	amount >>= PAGE_SHIFT;
3207	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3208	__sk_mem_reduce_allocated(sk, amount);
3209}
3210EXPORT_SYMBOL(__sk_mem_reclaim);
3211
3212int sk_set_peek_off(struct sock *sk, int val)
3213{
3214	WRITE_ONCE(sk->sk_peek_off, val);
3215	return 0;
3216}
3217EXPORT_SYMBOL_GPL(sk_set_peek_off);
3218
3219/*
3220 * Set of default routines for initialising struct proto_ops when
3221 * the protocol does not support a particular function. In certain
3222 * cases where it makes no sense for a protocol to have a "do nothing"
3223 * function, some default processing is provided.
3224 */
3225
3226int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3227{
3228	return -EOPNOTSUPP;
3229}
3230EXPORT_SYMBOL(sock_no_bind);
3231
3232int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3233		    int len, int flags)
3234{
3235	return -EOPNOTSUPP;
3236}
3237EXPORT_SYMBOL(sock_no_connect);
3238
3239int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3240{
3241	return -EOPNOTSUPP;
3242}
3243EXPORT_SYMBOL(sock_no_socketpair);
3244
3245int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3246		   bool kern)
3247{
3248	return -EOPNOTSUPP;
3249}
3250EXPORT_SYMBOL(sock_no_accept);
3251
3252int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3253		    int peer)
3254{
3255	return -EOPNOTSUPP;
3256}
3257EXPORT_SYMBOL(sock_no_getname);
3258
3259int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3260{
3261	return -EOPNOTSUPP;
3262}
3263EXPORT_SYMBOL(sock_no_ioctl);
3264
3265int sock_no_listen(struct socket *sock, int backlog)
3266{
3267	return -EOPNOTSUPP;
3268}
3269EXPORT_SYMBOL(sock_no_listen);
3270
3271int sock_no_shutdown(struct socket *sock, int how)
3272{
3273	return -EOPNOTSUPP;
3274}
3275EXPORT_SYMBOL(sock_no_shutdown);
3276
3277int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3278{
3279	return -EOPNOTSUPP;
3280}
3281EXPORT_SYMBOL(sock_no_sendmsg);
3282
3283int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3284{
3285	return -EOPNOTSUPP;
3286}
3287EXPORT_SYMBOL(sock_no_sendmsg_locked);
3288
3289int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3290		    int flags)
3291{
3292	return -EOPNOTSUPP;
3293}
3294EXPORT_SYMBOL(sock_no_recvmsg);
3295
3296int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3297{
3298	/* Mirror missing mmap method error code */
3299	return -ENODEV;
3300}
3301EXPORT_SYMBOL(sock_no_mmap);
3302
3303/*
3304 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3305 * various sock-based usage counts.
3306 */
3307void __receive_sock(struct file *file)
3308{
3309	struct socket *sock;
3310
3311	sock = sock_from_file(file);
3312	if (sock) {
3313		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3314		sock_update_classid(&sock->sk->sk_cgrp_data);
3315	}
3316}
3317
3318/*
3319 *	Default Socket Callbacks
3320 */
3321
3322static void sock_def_wakeup(struct sock *sk)
3323{
3324	struct socket_wq *wq;
3325
3326	rcu_read_lock();
3327	wq = rcu_dereference(sk->sk_wq);
3328	if (skwq_has_sleeper(wq))
3329		wake_up_interruptible_all(&wq->wait);
3330	rcu_read_unlock();
3331}
3332
3333static void sock_def_error_report(struct sock *sk)
3334{
3335	struct socket_wq *wq;
3336
3337	rcu_read_lock();
3338	wq = rcu_dereference(sk->sk_wq);
3339	if (skwq_has_sleeper(wq))
3340		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3341	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3342	rcu_read_unlock();
3343}
3344
3345void sock_def_readable(struct sock *sk)
3346{
3347	struct socket_wq *wq;
3348
3349	trace_sk_data_ready(sk);
3350
3351	rcu_read_lock();
3352	wq = rcu_dereference(sk->sk_wq);
3353	if (skwq_has_sleeper(wq))
3354		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3355						EPOLLRDNORM | EPOLLRDBAND);
3356	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3357	rcu_read_unlock();
3358}
3359
3360static void sock_def_write_space(struct sock *sk)
3361{
3362	struct socket_wq *wq;
3363
3364	rcu_read_lock();
3365
3366	/* Do not wake up a writer until he can make "significant"
3367	 * progress.  --DaveM
3368	 */
3369	if (sock_writeable(sk)) {
3370		wq = rcu_dereference(sk->sk_wq);
3371		if (skwq_has_sleeper(wq))
3372			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3373						EPOLLWRNORM | EPOLLWRBAND);
3374
3375		/* Should agree with poll, otherwise some programs break */
3376		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3377	}
3378
3379	rcu_read_unlock();
3380}
3381
3382/* An optimised version of sock_def_write_space(), should only be called
3383 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3384 * ->sk_wmem_alloc.
3385 */
3386static void sock_def_write_space_wfree(struct sock *sk)
3387{
3388	/* Do not wake up a writer until he can make "significant"
3389	 * progress.  --DaveM
3390	 */
3391	if (sock_writeable(sk)) {
3392		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3393
3394		/* rely on refcount_sub from sock_wfree() */
3395		smp_mb__after_atomic();
3396		if (wq && waitqueue_active(&wq->wait))
3397			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3398						EPOLLWRNORM | EPOLLWRBAND);
3399
3400		/* Should agree with poll, otherwise some programs break */
3401		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3402	}
3403}
3404
3405static void sock_def_destruct(struct sock *sk)
3406{
3407}
3408
3409void sk_send_sigurg(struct sock *sk)
3410{
3411	if (sk->sk_socket && sk->sk_socket->file)
3412		if (send_sigurg(&sk->sk_socket->file->f_owner))
3413			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3414}
3415EXPORT_SYMBOL(sk_send_sigurg);
3416
3417void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3418		    unsigned long expires)
3419{
3420	if (!mod_timer(timer, expires))
3421		sock_hold(sk);
3422}
3423EXPORT_SYMBOL(sk_reset_timer);
3424
3425void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3426{
3427	if (del_timer(timer))
3428		__sock_put(sk);
3429}
3430EXPORT_SYMBOL(sk_stop_timer);
3431
3432void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3433{
3434	if (del_timer_sync(timer))
3435		__sock_put(sk);
3436}
3437EXPORT_SYMBOL(sk_stop_timer_sync);
3438
3439void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3440{
3441	sk_init_common(sk);
3442	sk->sk_send_head	=	NULL;
3443
3444	timer_setup(&sk->sk_timer, NULL, 0);
3445
3446	sk->sk_allocation	=	GFP_KERNEL;
3447	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3448	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3449	sk->sk_state		=	TCP_CLOSE;
3450	sk->sk_use_task_frag	=	true;
3451	sk_set_socket(sk, sock);
3452
3453	sock_set_flag(sk, SOCK_ZAPPED);
3454
3455	if (sock) {
3456		sk->sk_type	=	sock->type;
3457		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3458		sock->sk	=	sk;
3459	} else {
3460		RCU_INIT_POINTER(sk->sk_wq, NULL);
3461	}
3462	sk->sk_uid	=	uid;
3463
3464	rwlock_init(&sk->sk_callback_lock);
3465	if (sk->sk_kern_sock)
3466		lockdep_set_class_and_name(
3467			&sk->sk_callback_lock,
3468			af_kern_callback_keys + sk->sk_family,
3469			af_family_kern_clock_key_strings[sk->sk_family]);
3470	else
3471		lockdep_set_class_and_name(
3472			&sk->sk_callback_lock,
3473			af_callback_keys + sk->sk_family,
3474			af_family_clock_key_strings[sk->sk_family]);
3475
3476	sk->sk_state_change	=	sock_def_wakeup;
3477	sk->sk_data_ready	=	sock_def_readable;
3478	sk->sk_write_space	=	sock_def_write_space;
3479	sk->sk_error_report	=	sock_def_error_report;
3480	sk->sk_destruct		=	sock_def_destruct;
3481
3482	sk->sk_frag.page	=	NULL;
3483	sk->sk_frag.offset	=	0;
3484	sk->sk_peek_off		=	-1;
3485
3486	sk->sk_peer_pid 	=	NULL;
3487	sk->sk_peer_cred	=	NULL;
3488	spin_lock_init(&sk->sk_peer_lock);
3489
3490	sk->sk_write_pending	=	0;
3491	sk->sk_rcvlowat		=	1;
3492	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3493	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3494
3495	sk->sk_stamp = SK_DEFAULT_STAMP;
3496#if BITS_PER_LONG==32
3497	seqlock_init(&sk->sk_stamp_seq);
3498#endif
3499	atomic_set(&sk->sk_zckey, 0);
3500
3501#ifdef CONFIG_NET_RX_BUSY_POLL
3502	sk->sk_napi_id		=	0;
3503	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3504#endif
3505
3506	sk->sk_max_pacing_rate = ~0UL;
3507	sk->sk_pacing_rate = ~0UL;
3508	WRITE_ONCE(sk->sk_pacing_shift, 10);
3509	sk->sk_incoming_cpu = -1;
3510
3511	sk_rx_queue_clear(sk);
3512	/*
3513	 * Before updating sk_refcnt, we must commit prior changes to memory
3514	 * (Documentation/RCU/rculist_nulls.rst for details)
3515	 */
3516	smp_wmb();
3517	refcount_set(&sk->sk_refcnt, 1);
3518	atomic_set(&sk->sk_drops, 0);
3519}
3520EXPORT_SYMBOL(sock_init_data_uid);
3521
3522void sock_init_data(struct socket *sock, struct sock *sk)
3523{
3524	kuid_t uid = sock ?
3525		SOCK_INODE(sock)->i_uid :
3526		make_kuid(sock_net(sk)->user_ns, 0);
3527
3528	sock_init_data_uid(sock, sk, uid);
3529}
3530EXPORT_SYMBOL(sock_init_data);
3531
3532void lock_sock_nested(struct sock *sk, int subclass)
3533{
3534	/* The sk_lock has mutex_lock() semantics here. */
3535	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3536
3537	might_sleep();
3538	spin_lock_bh(&sk->sk_lock.slock);
3539	if (sock_owned_by_user_nocheck(sk))
3540		__lock_sock(sk);
3541	sk->sk_lock.owned = 1;
3542	spin_unlock_bh(&sk->sk_lock.slock);
3543}
3544EXPORT_SYMBOL(lock_sock_nested);
3545
3546void release_sock(struct sock *sk)
3547{
3548	spin_lock_bh(&sk->sk_lock.slock);
3549	if (sk->sk_backlog.tail)
3550		__release_sock(sk);
3551
3552	if (sk->sk_prot->release_cb)
3553		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3554				     tcp_release_cb, sk);
3555
3556	sock_release_ownership(sk);
3557	if (waitqueue_active(&sk->sk_lock.wq))
3558		wake_up(&sk->sk_lock.wq);
3559	spin_unlock_bh(&sk->sk_lock.slock);
3560}
3561EXPORT_SYMBOL(release_sock);
3562
3563bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3564{
3565	might_sleep();
3566	spin_lock_bh(&sk->sk_lock.slock);
3567
3568	if (!sock_owned_by_user_nocheck(sk)) {
3569		/*
3570		 * Fast path return with bottom halves disabled and
3571		 * sock::sk_lock.slock held.
3572		 *
3573		 * The 'mutex' is not contended and holding
3574		 * sock::sk_lock.slock prevents all other lockers to
3575		 * proceed so the corresponding unlock_sock_fast() can
3576		 * avoid the slow path of release_sock() completely and
3577		 * just release slock.
3578		 *
3579		 * From a semantical POV this is equivalent to 'acquiring'
3580		 * the 'mutex', hence the corresponding lockdep
3581		 * mutex_release() has to happen in the fast path of
3582		 * unlock_sock_fast().
3583		 */
3584		return false;
3585	}
3586
3587	__lock_sock(sk);
3588	sk->sk_lock.owned = 1;
3589	__acquire(&sk->sk_lock.slock);
3590	spin_unlock_bh(&sk->sk_lock.slock);
3591	return true;
3592}
3593EXPORT_SYMBOL(__lock_sock_fast);
3594
3595int sock_gettstamp(struct socket *sock, void __user *userstamp,
3596		   bool timeval, bool time32)
3597{
3598	struct sock *sk = sock->sk;
3599	struct timespec64 ts;
3600
3601	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3602	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3603	if (ts.tv_sec == -1)
3604		return -ENOENT;
3605	if (ts.tv_sec == 0) {
3606		ktime_t kt = ktime_get_real();
3607		sock_write_timestamp(sk, kt);
3608		ts = ktime_to_timespec64(kt);
3609	}
3610
3611	if (timeval)
3612		ts.tv_nsec /= 1000;
3613
3614#ifdef CONFIG_COMPAT_32BIT_TIME
3615	if (time32)
3616		return put_old_timespec32(&ts, userstamp);
3617#endif
3618#ifdef CONFIG_SPARC64
3619	/* beware of padding in sparc64 timeval */
3620	if (timeval && !in_compat_syscall()) {
3621		struct __kernel_old_timeval __user tv = {
3622			.tv_sec = ts.tv_sec,
3623			.tv_usec = ts.tv_nsec,
3624		};
3625		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3626			return -EFAULT;
3627		return 0;
3628	}
3629#endif
3630	return put_timespec64(&ts, userstamp);
3631}
3632EXPORT_SYMBOL(sock_gettstamp);
3633
3634void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3635{
3636	if (!sock_flag(sk, flag)) {
3637		unsigned long previous_flags = sk->sk_flags;
3638
3639		sock_set_flag(sk, flag);
3640		/*
3641		 * we just set one of the two flags which require net
3642		 * time stamping, but time stamping might have been on
3643		 * already because of the other one
3644		 */
3645		if (sock_needs_netstamp(sk) &&
3646		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3647			net_enable_timestamp();
3648	}
3649}
3650
3651int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3652		       int level, int type)
3653{
3654	struct sock_exterr_skb *serr;
3655	struct sk_buff *skb;
3656	int copied, err;
3657
3658	err = -EAGAIN;
3659	skb = sock_dequeue_err_skb(sk);
3660	if (skb == NULL)
3661		goto out;
3662
3663	copied = skb->len;
3664	if (copied > len) {
3665		msg->msg_flags |= MSG_TRUNC;
3666		copied = len;
3667	}
3668	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3669	if (err)
3670		goto out_free_skb;
3671
3672	sock_recv_timestamp(msg, sk, skb);
3673
3674	serr = SKB_EXT_ERR(skb);
3675	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3676
3677	msg->msg_flags |= MSG_ERRQUEUE;
3678	err = copied;
3679
3680out_free_skb:
3681	kfree_skb(skb);
3682out:
3683	return err;
3684}
3685EXPORT_SYMBOL(sock_recv_errqueue);
3686
3687/*
3688 *	Get a socket option on an socket.
3689 *
3690 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3691 *	asynchronous errors should be reported by getsockopt. We assume
3692 *	this means if you specify SO_ERROR (otherwise whats the point of it).
3693 */
3694int sock_common_getsockopt(struct socket *sock, int level, int optname,
3695			   char __user *optval, int __user *optlen)
3696{
3697	struct sock *sk = sock->sk;
3698
3699	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3700	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3701}
3702EXPORT_SYMBOL(sock_common_getsockopt);
3703
3704int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3705			int flags)
3706{
3707	struct sock *sk = sock->sk;
3708	int addr_len = 0;
3709	int err;
3710
3711	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3712	if (err >= 0)
3713		msg->msg_namelen = addr_len;
3714	return err;
3715}
3716EXPORT_SYMBOL(sock_common_recvmsg);
3717
3718/*
3719 *	Set socket options on an inet socket.
3720 */
3721int sock_common_setsockopt(struct socket *sock, int level, int optname,
3722			   sockptr_t optval, unsigned int optlen)
3723{
3724	struct sock *sk = sock->sk;
3725
3726	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3727	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3728}
3729EXPORT_SYMBOL(sock_common_setsockopt);
3730
3731void sk_common_release(struct sock *sk)
3732{
3733	if (sk->sk_prot->destroy)
3734		sk->sk_prot->destroy(sk);
3735
3736	/*
3737	 * Observation: when sk_common_release is called, processes have
3738	 * no access to socket. But net still has.
3739	 * Step one, detach it from networking:
3740	 *
3741	 * A. Remove from hash tables.
3742	 */
3743
3744	sk->sk_prot->unhash(sk);
3745
3746	/*
3747	 * In this point socket cannot receive new packets, but it is possible
3748	 * that some packets are in flight because some CPU runs receiver and
3749	 * did hash table lookup before we unhashed socket. They will achieve
3750	 * receive queue and will be purged by socket destructor.
3751	 *
3752	 * Also we still have packets pending on receive queue and probably,
3753	 * our own packets waiting in device queues. sock_destroy will drain
3754	 * receive queue, but transmitted packets will delay socket destruction
3755	 * until the last reference will be released.
3756	 */
3757
3758	sock_orphan(sk);
3759
3760	xfrm_sk_free_policy(sk);
3761
3762	sock_put(sk);
3763}
3764EXPORT_SYMBOL(sk_common_release);
3765
3766void sk_get_meminfo(const struct sock *sk, u32 *mem)
3767{
3768	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3769
3770	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3771	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3772	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3773	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3774	mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk);
3775	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3776	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3777	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3778	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3779}
3780
3781#ifdef CONFIG_PROC_FS
3782static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3783
3784int sock_prot_inuse_get(struct net *net, struct proto *prot)
3785{
3786	int cpu, idx = prot->inuse_idx;
3787	int res = 0;
3788
3789	for_each_possible_cpu(cpu)
3790		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3791
3792	return res >= 0 ? res : 0;
3793}
3794EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3795
3796int sock_inuse_get(struct net *net)
3797{
3798	int cpu, res = 0;
3799
3800	for_each_possible_cpu(cpu)
3801		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3802
3803	return res;
3804}
3805
3806EXPORT_SYMBOL_GPL(sock_inuse_get);
3807
3808static int __net_init sock_inuse_init_net(struct net *net)
3809{
3810	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3811	if (net->core.prot_inuse == NULL)
3812		return -ENOMEM;
3813	return 0;
3814}
3815
3816static void __net_exit sock_inuse_exit_net(struct net *net)
3817{
3818	free_percpu(net->core.prot_inuse);
3819}
3820
3821static struct pernet_operations net_inuse_ops = {
3822	.init = sock_inuse_init_net,
3823	.exit = sock_inuse_exit_net,
3824};
3825
3826static __init int net_inuse_init(void)
3827{
3828	if (register_pernet_subsys(&net_inuse_ops))
3829		panic("Cannot initialize net inuse counters");
3830
3831	return 0;
3832}
3833
3834core_initcall(net_inuse_init);
3835
3836static int assign_proto_idx(struct proto *prot)
3837{
3838	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3839
3840	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3841		pr_err("PROTO_INUSE_NR exhausted\n");
3842		return -ENOSPC;
3843	}
3844
3845	set_bit(prot->inuse_idx, proto_inuse_idx);
3846	return 0;
3847}
3848
3849static void release_proto_idx(struct proto *prot)
3850{
3851	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3852		clear_bit(prot->inuse_idx, proto_inuse_idx);
3853}
3854#else
3855static inline int assign_proto_idx(struct proto *prot)
3856{
3857	return 0;
3858}
3859
3860static inline void release_proto_idx(struct proto *prot)
3861{
3862}
3863
3864#endif
3865
3866static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3867{
3868	if (!twsk_prot)
3869		return;
3870	kfree(twsk_prot->twsk_slab_name);
3871	twsk_prot->twsk_slab_name = NULL;
3872	kmem_cache_destroy(twsk_prot->twsk_slab);
3873	twsk_prot->twsk_slab = NULL;
3874}
3875
3876static int tw_prot_init(const struct proto *prot)
3877{
3878	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3879
3880	if (!twsk_prot)
3881		return 0;
3882
3883	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3884					      prot->name);
3885	if (!twsk_prot->twsk_slab_name)
3886		return -ENOMEM;
3887
3888	twsk_prot->twsk_slab =
3889		kmem_cache_create(twsk_prot->twsk_slab_name,
3890				  twsk_prot->twsk_obj_size, 0,
3891				  SLAB_ACCOUNT | prot->slab_flags,
3892				  NULL);
3893	if (!twsk_prot->twsk_slab) {
3894		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3895			prot->name);
3896		return -ENOMEM;
3897	}
3898
3899	return 0;
3900}
3901
3902static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3903{
3904	if (!rsk_prot)
3905		return;
3906	kfree(rsk_prot->slab_name);
3907	rsk_prot->slab_name = NULL;
3908	kmem_cache_destroy(rsk_prot->slab);
3909	rsk_prot->slab = NULL;
3910}
3911
3912static int req_prot_init(const struct proto *prot)
3913{
3914	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3915
3916	if (!rsk_prot)
3917		return 0;
3918
3919	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3920					prot->name);
3921	if (!rsk_prot->slab_name)
3922		return -ENOMEM;
3923
3924	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3925					   rsk_prot->obj_size, 0,
3926					   SLAB_ACCOUNT | prot->slab_flags,
3927					   NULL);
3928
3929	if (!rsk_prot->slab) {
3930		pr_crit("%s: Can't create request sock SLAB cache!\n",
3931			prot->name);
3932		return -ENOMEM;
3933	}
3934	return 0;
3935}
3936
3937int proto_register(struct proto *prot, int alloc_slab)
3938{
3939	int ret = -ENOBUFS;
3940
3941	if (prot->memory_allocated && !prot->sysctl_mem) {
3942		pr_err("%s: missing sysctl_mem\n", prot->name);
3943		return -EINVAL;
3944	}
3945	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3946		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3947		return -EINVAL;
3948	}
3949	if (alloc_slab) {
3950		prot->slab = kmem_cache_create_usercopy(prot->name,
3951					prot->obj_size, 0,
3952					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3953					prot->slab_flags,
3954					prot->useroffset, prot->usersize,
3955					NULL);
3956
3957		if (prot->slab == NULL) {
3958			pr_crit("%s: Can't create sock SLAB cache!\n",
3959				prot->name);
3960			goto out;
3961		}
3962
3963		if (req_prot_init(prot))
3964			goto out_free_request_sock_slab;
3965
3966		if (tw_prot_init(prot))
3967			goto out_free_timewait_sock_slab;
3968	}
3969
3970	mutex_lock(&proto_list_mutex);
3971	ret = assign_proto_idx(prot);
3972	if (ret) {
3973		mutex_unlock(&proto_list_mutex);
3974		goto out_free_timewait_sock_slab;
3975	}
3976	list_add(&prot->node, &proto_list);
3977	mutex_unlock(&proto_list_mutex);
3978	return ret;
3979
3980out_free_timewait_sock_slab:
3981	if (alloc_slab)
3982		tw_prot_cleanup(prot->twsk_prot);
3983out_free_request_sock_slab:
3984	if (alloc_slab) {
3985		req_prot_cleanup(prot->rsk_prot);
3986
3987		kmem_cache_destroy(prot->slab);
3988		prot->slab = NULL;
3989	}
3990out:
3991	return ret;
3992}
3993EXPORT_SYMBOL(proto_register);
3994
3995void proto_unregister(struct proto *prot)
3996{
3997	mutex_lock(&proto_list_mutex);
3998	release_proto_idx(prot);
3999	list_del(&prot->node);
4000	mutex_unlock(&proto_list_mutex);
4001
4002	kmem_cache_destroy(prot->slab);
4003	prot->slab = NULL;
4004
4005	req_prot_cleanup(prot->rsk_prot);
4006	tw_prot_cleanup(prot->twsk_prot);
4007}
4008EXPORT_SYMBOL(proto_unregister);
4009
4010int sock_load_diag_module(int family, int protocol)
4011{
4012	if (!protocol) {
4013		if (!sock_is_registered(family))
4014			return -ENOENT;
4015
4016		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4017				      NETLINK_SOCK_DIAG, family);
4018	}
4019
4020#ifdef CONFIG_INET
4021	if (family == AF_INET &&
4022	    protocol != IPPROTO_RAW &&
4023	    protocol < MAX_INET_PROTOS &&
4024	    !rcu_access_pointer(inet_protos[protocol]))
4025		return -ENOENT;
4026#endif
4027
4028	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4029			      NETLINK_SOCK_DIAG, family, protocol);
4030}
4031EXPORT_SYMBOL(sock_load_diag_module);
4032
4033#ifdef CONFIG_PROC_FS
4034static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4035	__acquires(proto_list_mutex)
4036{
4037	mutex_lock(&proto_list_mutex);
4038	return seq_list_start_head(&proto_list, *pos);
4039}
4040
4041static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4042{
4043	return seq_list_next(v, &proto_list, pos);
4044}
4045
4046static void proto_seq_stop(struct seq_file *seq, void *v)
4047	__releases(proto_list_mutex)
4048{
4049	mutex_unlock(&proto_list_mutex);
4050}
4051
4052static char proto_method_implemented(const void *method)
4053{
4054	return method == NULL ? 'n' : 'y';
4055}
4056static long sock_prot_memory_allocated(struct proto *proto)
4057{
4058	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4059}
4060
4061static const char *sock_prot_memory_pressure(struct proto *proto)
4062{
4063	return proto->memory_pressure != NULL ?
4064	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4065}
4066
4067static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4068{
4069
4070	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4071			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4072		   proto->name,
4073		   proto->obj_size,
4074		   sock_prot_inuse_get(seq_file_net(seq), proto),
4075		   sock_prot_memory_allocated(proto),
4076		   sock_prot_memory_pressure(proto),
4077		   proto->max_header,
4078		   proto->slab == NULL ? "no" : "yes",
4079		   module_name(proto->owner),
4080		   proto_method_implemented(proto->close),
4081		   proto_method_implemented(proto->connect),
4082		   proto_method_implemented(proto->disconnect),
4083		   proto_method_implemented(proto->accept),
4084		   proto_method_implemented(proto->ioctl),
4085		   proto_method_implemented(proto->init),
4086		   proto_method_implemented(proto->destroy),
4087		   proto_method_implemented(proto->shutdown),
4088		   proto_method_implemented(proto->setsockopt),
4089		   proto_method_implemented(proto->getsockopt),
4090		   proto_method_implemented(proto->sendmsg),
4091		   proto_method_implemented(proto->recvmsg),
4092		   proto_method_implemented(proto->bind),
4093		   proto_method_implemented(proto->backlog_rcv),
4094		   proto_method_implemented(proto->hash),
4095		   proto_method_implemented(proto->unhash),
4096		   proto_method_implemented(proto->get_port),
4097		   proto_method_implemented(proto->enter_memory_pressure));
4098}
4099
4100static int proto_seq_show(struct seq_file *seq, void *v)
4101{
4102	if (v == &proto_list)
4103		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4104			   "protocol",
4105			   "size",
4106			   "sockets",
4107			   "memory",
4108			   "press",
4109			   "maxhdr",
4110			   "slab",
4111			   "module",
4112			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4113	else
4114		proto_seq_printf(seq, list_entry(v, struct proto, node));
4115	return 0;
4116}
4117
4118static const struct seq_operations proto_seq_ops = {
4119	.start  = proto_seq_start,
4120	.next   = proto_seq_next,
4121	.stop   = proto_seq_stop,
4122	.show   = proto_seq_show,
4123};
4124
4125static __net_init int proto_init_net(struct net *net)
4126{
4127	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4128			sizeof(struct seq_net_private)))
4129		return -ENOMEM;
4130
4131	return 0;
4132}
4133
4134static __net_exit void proto_exit_net(struct net *net)
4135{
4136	remove_proc_entry("protocols", net->proc_net);
4137}
4138
4139
4140static __net_initdata struct pernet_operations proto_net_ops = {
4141	.init = proto_init_net,
4142	.exit = proto_exit_net,
4143};
4144
4145static int __init proto_init(void)
4146{
4147	return register_pernet_subsys(&proto_net_ops);
4148}
4149
4150subsys_initcall(proto_init);
4151
4152#endif /* PROC_FS */
4153
4154#ifdef CONFIG_NET_RX_BUSY_POLL
4155bool sk_busy_loop_end(void *p, unsigned long start_time)
4156{
4157	struct sock *sk = p;
4158
4159	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4160		return true;
4161
4162	if (sk_is_udp(sk) &&
4163	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4164		return true;
4165
4166	return sk_busy_loop_timeout(sk, start_time);
4167}
4168EXPORT_SYMBOL(sk_busy_loop_end);
4169#endif /* CONFIG_NET_RX_BUSY_POLL */
4170
4171int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4172{
4173	if (!sk->sk_prot->bind_add)
4174		return -EOPNOTSUPP;
4175	return sk->sk_prot->bind_add(sk, addr, addr_len);
4176}
4177EXPORT_SYMBOL(sock_bind_add);
4178
4179/* Copy 'size' bytes from userspace and return `size` back to userspace */
4180int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4181		     void __user *arg, void *karg, size_t size)
4182{
4183	int ret;
4184
4185	if (copy_from_user(karg, arg, size))
4186		return -EFAULT;
4187
4188	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4189	if (ret)
4190		return ret;
4191
4192	if (copy_to_user(arg, karg, size))
4193		return -EFAULT;
4194
4195	return 0;
4196}
4197EXPORT_SYMBOL(sock_ioctl_inout);
4198
4199/* This is the most common ioctl prep function, where the result (4 bytes) is
4200 * copied back to userspace if the ioctl() returns successfully. No input is
4201 * copied from userspace as input argument.
4202 */
4203static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4204{
4205	int ret, karg = 0;
4206
4207	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4208	if (ret)
4209		return ret;
4210
4211	return put_user(karg, (int __user *)arg);
4212}
4213
4214/* A wrapper around sock ioctls, which copies the data from userspace
4215 * (depending on the protocol/ioctl), and copies back the result to userspace.
4216 * The main motivation for this function is to pass kernel memory to the
4217 * protocol ioctl callbacks, instead of userspace memory.
4218 */
4219int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4220{
4221	int rc = 1;
4222
4223	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4224		rc = ipmr_sk_ioctl(sk, cmd, arg);
4225	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4226		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4227	else if (sk_is_phonet(sk))
4228		rc = phonet_sk_ioctl(sk, cmd, arg);
4229
4230	/* If ioctl was processed, returns its value */
4231	if (rc <= 0)
4232		return rc;
4233
4234	/* Otherwise call the default handler */
4235	return sock_ioctl_out(sk, cmd, arg);
4236}
4237EXPORT_SYMBOL(sk_ioctl);
4238
4239static int __init sock_struct_check(void)
4240{
4241	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4242	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4243	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4244	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4245	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4246
4247	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4248	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4249	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4250	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4251	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4252	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4253	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4254	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4255	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4256
4257	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4258	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4259	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4260
4261	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4262	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4263	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4264	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4265
4266	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4267	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4268	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_sndbuf);
4269	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4270	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4271	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4272	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4273	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4274	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4275	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm);
4276	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status);
4277	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4278	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4279	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4280	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4281	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4282
4283	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4284	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4285	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4286	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4287	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4288	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4289	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4290	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4291	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4292	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4293	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4294	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4295	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4296	return 0;
4297}
4298
4299core_initcall(sock_struct_check);
4300