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 INET transport hashtables
8 *
9 * Authors: Lotsa people, from code originally in tcp
10 */
11
12#include <linux/module.h>
13#include <linux/random.h>
14#include <linux/sched.h>
15#include <linux/slab.h>
16#include <linux/wait.h>
17#include <linux/vmalloc.h>
18#include <linux/memblock.h>
19
20#include <net/addrconf.h>
21#include <net/inet_connection_sock.h>
22#include <net/inet_hashtables.h>
23#if IS_ENABLED(CONFIG_IPV6)
24#include <net/inet6_hashtables.h>
25#endif
26#include <net/secure_seq.h>
27#include <net/hotdata.h>
28#include <net/ip.h>
29#include <net/tcp.h>
30#include <net/sock_reuseport.h>
31
32u32 inet_ehashfn(const struct net *net, const __be32 laddr,
33 const __u16 lport, const __be32 faddr,
34 const __be16 fport)
35{
36 net_get_random_once(&inet_ehash_secret, sizeof(inet_ehash_secret));
37
38 return __inet_ehashfn(laddr, lport, faddr, fport,
39 inet_ehash_secret + net_hash_mix(net));
40}
41EXPORT_SYMBOL_GPL(inet_ehashfn);
42
43/* This function handles inet_sock, but also timewait and request sockets
44 * for IPv4/IPv6.
45 */
46static u32 sk_ehashfn(const struct sock *sk)
47{
48#if IS_ENABLED(CONFIG_IPV6)
49 if (sk->sk_family == AF_INET6 &&
50 !ipv6_addr_v4mapped(a: &sk->sk_v6_daddr))
51 return inet6_ehashfn(sock_net(sk),
52 &sk->sk_v6_rcv_saddr, sk->sk_num,
53 &sk->sk_v6_daddr, sk->sk_dport);
54#endif
55 return inet_ehashfn(sock_net(sk),
56 sk->sk_rcv_saddr, sk->sk_num,
57 sk->sk_daddr, sk->sk_dport);
58}
59
60/*
61 * Allocate and initialize a new local port bind bucket.
62 * The bindhash mutex for snum's hash chain must be held here.
63 */
64struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
65 struct net *net,
66 struct inet_bind_hashbucket *head,
67 const unsigned short snum,
68 int l3mdev)
69{
70 struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
71
72 if (tb) {
73 write_pnet(pnet: &tb->ib_net, net);
74 tb->l3mdev = l3mdev;
75 tb->port = snum;
76 tb->fastreuse = 0;
77 tb->fastreuseport = 0;
78 INIT_HLIST_HEAD(&tb->bhash2);
79 hlist_add_head(n: &tb->node, h: &head->chain);
80 }
81 return tb;
82}
83
84/*
85 * Caller must hold hashbucket lock for this tb with local BH disabled
86 */
87void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket *tb)
88{
89 if (hlist_empty(h: &tb->bhash2)) {
90 __hlist_del(n: &tb->node);
91 kmem_cache_free(s: cachep, objp: tb);
92 }
93}
94
95bool inet_bind_bucket_match(const struct inet_bind_bucket *tb, const struct net *net,
96 unsigned short port, int l3mdev)
97{
98 return net_eq(net1: ib_net(ib: tb), net2: net) && tb->port == port &&
99 tb->l3mdev == l3mdev;
100}
101
102static void inet_bind2_bucket_init(struct inet_bind2_bucket *tb2,
103 struct net *net,
104 struct inet_bind_hashbucket *head,
105 struct inet_bind_bucket *tb,
106 const struct sock *sk)
107{
108 write_pnet(pnet: &tb2->ib_net, net);
109 tb2->l3mdev = tb->l3mdev;
110 tb2->port = tb->port;
111#if IS_ENABLED(CONFIG_IPV6)
112 BUILD_BUG_ON(USHRT_MAX < (IPV6_ADDR_ANY | IPV6_ADDR_MAPPED));
113 if (sk->sk_family == AF_INET6) {
114 tb2->addr_type = ipv6_addr_type(addr: &sk->sk_v6_rcv_saddr);
115 tb2->v6_rcv_saddr = sk->sk_v6_rcv_saddr;
116 } else {
117 tb2->addr_type = IPV6_ADDR_MAPPED;
118 ipv6_addr_set_v4mapped(addr: sk->sk_rcv_saddr, v4mapped: &tb2->v6_rcv_saddr);
119 }
120#else
121 tb2->rcv_saddr = sk->sk_rcv_saddr;
122#endif
123 INIT_HLIST_HEAD(&tb2->owners);
124 hlist_add_head(n: &tb2->node, h: &head->chain);
125 hlist_add_head(n: &tb2->bhash_node, h: &tb->bhash2);
126}
127
128struct inet_bind2_bucket *inet_bind2_bucket_create(struct kmem_cache *cachep,
129 struct net *net,
130 struct inet_bind_hashbucket *head,
131 struct inet_bind_bucket *tb,
132 const struct sock *sk)
133{
134 struct inet_bind2_bucket *tb2 = kmem_cache_alloc(cachep, GFP_ATOMIC);
135
136 if (tb2)
137 inet_bind2_bucket_init(tb2, net, head, tb, sk);
138
139 return tb2;
140}
141
142/* Caller must hold hashbucket lock for this tb with local BH disabled */
143void inet_bind2_bucket_destroy(struct kmem_cache *cachep, struct inet_bind2_bucket *tb)
144{
145 if (hlist_empty(h: &tb->owners)) {
146 __hlist_del(n: &tb->node);
147 __hlist_del(n: &tb->bhash_node);
148 kmem_cache_free(s: cachep, objp: tb);
149 }
150}
151
152static bool inet_bind2_bucket_addr_match(const struct inet_bind2_bucket *tb2,
153 const struct sock *sk)
154{
155#if IS_ENABLED(CONFIG_IPV6)
156 if (sk->sk_family == AF_INET6)
157 return ipv6_addr_equal(a1: &tb2->v6_rcv_saddr, a2: &sk->sk_v6_rcv_saddr);
158
159 if (tb2->addr_type != IPV6_ADDR_MAPPED)
160 return false;
161#endif
162 return tb2->rcv_saddr == sk->sk_rcv_saddr;
163}
164
165void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
166 struct inet_bind2_bucket *tb2, unsigned short port)
167{
168 inet_sk(sk)->inet_num = port;
169 inet_csk(sk)->icsk_bind_hash = tb;
170 inet_csk(sk)->icsk_bind2_hash = tb2;
171 sk_add_bind_node(sk, list: &tb2->owners);
172}
173
174/*
175 * Get rid of any references to a local port held by the given sock.
176 */
177static void __inet_put_port(struct sock *sk)
178{
179 struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
180 struct inet_bind_hashbucket *head, *head2;
181 struct net *net = sock_net(sk);
182 struct inet_bind_bucket *tb;
183 int bhash;
184
185 bhash = inet_bhashfn(net, inet_sk(sk)->inet_num, bhash_size: hashinfo->bhash_size);
186 head = &hashinfo->bhash[bhash];
187 head2 = inet_bhashfn_portaddr(hinfo: hashinfo, sk, net, inet_sk(sk)->inet_num);
188
189 spin_lock(lock: &head->lock);
190 tb = inet_csk(sk)->icsk_bind_hash;
191 inet_csk(sk)->icsk_bind_hash = NULL;
192 inet_sk(sk)->inet_num = 0;
193
194 spin_lock(lock: &head2->lock);
195 if (inet_csk(sk)->icsk_bind2_hash) {
196 struct inet_bind2_bucket *tb2 = inet_csk(sk)->icsk_bind2_hash;
197
198 __sk_del_bind_node(sk);
199 inet_csk(sk)->icsk_bind2_hash = NULL;
200 inet_bind2_bucket_destroy(cachep: hashinfo->bind2_bucket_cachep, tb: tb2);
201 }
202 spin_unlock(lock: &head2->lock);
203
204 inet_bind_bucket_destroy(cachep: hashinfo->bind_bucket_cachep, tb);
205 spin_unlock(lock: &head->lock);
206}
207
208void inet_put_port(struct sock *sk)
209{
210 local_bh_disable();
211 __inet_put_port(sk);
212 local_bh_enable();
213}
214EXPORT_SYMBOL(inet_put_port);
215
216int __inet_inherit_port(const struct sock *sk, struct sock *child)
217{
218 struct inet_hashinfo *table = tcp_or_dccp_get_hashinfo(sk);
219 unsigned short port = inet_sk(child)->inet_num;
220 struct inet_bind_hashbucket *head, *head2;
221 bool created_inet_bind_bucket = false;
222 struct net *net = sock_net(sk);
223 bool update_fastreuse = false;
224 struct inet_bind2_bucket *tb2;
225 struct inet_bind_bucket *tb;
226 int bhash, l3mdev;
227
228 bhash = inet_bhashfn(net, lport: port, bhash_size: table->bhash_size);
229 head = &table->bhash[bhash];
230 head2 = inet_bhashfn_portaddr(hinfo: table, sk: child, net, port);
231
232 spin_lock(lock: &head->lock);
233 spin_lock(lock: &head2->lock);
234 tb = inet_csk(sk)->icsk_bind_hash;
235 tb2 = inet_csk(sk)->icsk_bind2_hash;
236 if (unlikely(!tb || !tb2)) {
237 spin_unlock(lock: &head2->lock);
238 spin_unlock(lock: &head->lock);
239 return -ENOENT;
240 }
241 if (tb->port != port) {
242 l3mdev = inet_sk_bound_l3mdev(sk);
243
244 /* NOTE: using tproxy and redirecting skbs to a proxy
245 * on a different listener port breaks the assumption
246 * that the listener socket's icsk_bind_hash is the same
247 * as that of the child socket. We have to look up or
248 * create a new bind bucket for the child here. */
249 inet_bind_bucket_for_each(tb, &head->chain) {
250 if (inet_bind_bucket_match(tb, net, port, l3mdev))
251 break;
252 }
253 if (!tb) {
254 tb = inet_bind_bucket_create(cachep: table->bind_bucket_cachep,
255 net, head, snum: port, l3mdev);
256 if (!tb) {
257 spin_unlock(lock: &head2->lock);
258 spin_unlock(lock: &head->lock);
259 return -ENOMEM;
260 }
261 created_inet_bind_bucket = true;
262 }
263 update_fastreuse = true;
264
265 goto bhash2_find;
266 } else if (!inet_bind2_bucket_addr_match(tb2, sk: child)) {
267 l3mdev = inet_sk_bound_l3mdev(sk);
268
269bhash2_find:
270 tb2 = inet_bind2_bucket_find(head: head2, net, port, l3mdev, sk: child);
271 if (!tb2) {
272 tb2 = inet_bind2_bucket_create(cachep: table->bind2_bucket_cachep,
273 net, head: head2, tb, sk: child);
274 if (!tb2)
275 goto error;
276 }
277 }
278 if (update_fastreuse)
279 inet_csk_update_fastreuse(tb, sk: child);
280 inet_bind_hash(sk: child, tb, tb2, port);
281 spin_unlock(lock: &head2->lock);
282 spin_unlock(lock: &head->lock);
283
284 return 0;
285
286error:
287 if (created_inet_bind_bucket)
288 inet_bind_bucket_destroy(cachep: table->bind_bucket_cachep, tb);
289 spin_unlock(lock: &head2->lock);
290 spin_unlock(lock: &head->lock);
291 return -ENOMEM;
292}
293EXPORT_SYMBOL_GPL(__inet_inherit_port);
294
295static struct inet_listen_hashbucket *
296inet_lhash2_bucket_sk(struct inet_hashinfo *h, struct sock *sk)
297{
298 u32 hash;
299
300#if IS_ENABLED(CONFIG_IPV6)
301 if (sk->sk_family == AF_INET6)
302 hash = ipv6_portaddr_hash(net: sock_net(sk),
303 addr6: &sk->sk_v6_rcv_saddr,
304 inet_sk(sk)->inet_num);
305 else
306#endif
307 hash = ipv4_portaddr_hash(net: sock_net(sk),
308 inet_sk(sk)->inet_rcv_saddr,
309 inet_sk(sk)->inet_num);
310 return inet_lhash2_bucket(h, hash);
311}
312
313static inline int compute_score(struct sock *sk, struct net *net,
314 const unsigned short hnum, const __be32 daddr,
315 const int dif, const int sdif)
316{
317 int score = -1;
318
319 if (net_eq(net1: sock_net(sk), net2: net) && sk->sk_num == hnum &&
320 !ipv6_only_sock(sk)) {
321 if (sk->sk_rcv_saddr != daddr)
322 return -1;
323
324 if (!inet_sk_bound_dev_eq(net, bound_dev_if: sk->sk_bound_dev_if, dif, sdif))
325 return -1;
326 score = sk->sk_bound_dev_if ? 2 : 1;
327
328 if (sk->sk_family == PF_INET)
329 score++;
330 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
331 score++;
332 }
333 return score;
334}
335
336/**
337 * inet_lookup_reuseport() - execute reuseport logic on AF_INET socket if necessary.
338 * @net: network namespace.
339 * @sk: AF_INET socket, must be in TCP_LISTEN state for TCP or TCP_CLOSE for UDP.
340 * @skb: context for a potential SK_REUSEPORT program.
341 * @doff: header offset.
342 * @saddr: source address.
343 * @sport: source port.
344 * @daddr: destination address.
345 * @hnum: destination port in host byte order.
346 * @ehashfn: hash function used to generate the fallback hash.
347 *
348 * Return: NULL if sk doesn't have SO_REUSEPORT set, otherwise a pointer to
349 * the selected sock or an error.
350 */
351struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
352 struct sk_buff *skb, int doff,
353 __be32 saddr, __be16 sport,
354 __be32 daddr, unsigned short hnum,
355 inet_ehashfn_t *ehashfn)
356{
357 struct sock *reuse_sk = NULL;
358 u32 phash;
359
360 if (sk->sk_reuseport) {
361 phash = INDIRECT_CALL_2(ehashfn, udp_ehashfn, inet_ehashfn,
362 net, daddr, hnum, saddr, sport);
363 reuse_sk = reuseport_select_sock(sk, hash: phash, skb, hdr_len: doff);
364 }
365 return reuse_sk;
366}
367EXPORT_SYMBOL_GPL(inet_lookup_reuseport);
368
369/*
370 * Here are some nice properties to exploit here. The BSD API
371 * does not allow a listening sock to specify the remote port nor the
372 * remote address for the connection. So always assume those are both
373 * wildcarded during the search since they can never be otherwise.
374 */
375
376/* called with rcu_read_lock() : No refcount taken on the socket */
377static struct sock *inet_lhash2_lookup(struct net *net,
378 struct inet_listen_hashbucket *ilb2,
379 struct sk_buff *skb, int doff,
380 const __be32 saddr, __be16 sport,
381 const __be32 daddr, const unsigned short hnum,
382 const int dif, const int sdif)
383{
384 struct sock *sk, *result = NULL;
385 struct hlist_nulls_node *node;
386 int score, hiscore = 0;
387
388 sk_nulls_for_each_rcu(sk, node, &ilb2->nulls_head) {
389 score = compute_score(sk, net, hnum, daddr, dif, sdif);
390 if (score > hiscore) {
391 result = inet_lookup_reuseport(net, sk, skb, doff,
392 saddr, sport, daddr, hnum, inet_ehashfn);
393 if (result)
394 return result;
395
396 result = sk;
397 hiscore = score;
398 }
399 }
400
401 return result;
402}
403
404struct sock *inet_lookup_run_sk_lookup(struct net *net,
405 int protocol,
406 struct sk_buff *skb, int doff,
407 __be32 saddr, __be16 sport,
408 __be32 daddr, u16 hnum, const int dif,
409 inet_ehashfn_t *ehashfn)
410{
411 struct sock *sk, *reuse_sk;
412 bool no_reuseport;
413
414 no_reuseport = bpf_sk_lookup_run_v4(net, protocol, saddr, sport,
415 daddr, dport: hnum, ifindex: dif, psk: &sk);
416 if (no_reuseport || IS_ERR_OR_NULL(ptr: sk))
417 return sk;
418
419 reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum,
420 ehashfn);
421 if (reuse_sk)
422 sk = reuse_sk;
423 return sk;
424}
425
426struct sock *__inet_lookup_listener(struct net *net,
427 struct inet_hashinfo *hashinfo,
428 struct sk_buff *skb, int doff,
429 const __be32 saddr, __be16 sport,
430 const __be32 daddr, const unsigned short hnum,
431 const int dif, const int sdif)
432{
433 struct inet_listen_hashbucket *ilb2;
434 struct sock *result = NULL;
435 unsigned int hash2;
436
437 /* Lookup redirect from BPF */
438 if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
439 hashinfo == net->ipv4.tcp_death_row.hashinfo) {
440 result = inet_lookup_run_sk_lookup(net, IPPROTO_TCP, skb, doff,
441 saddr, sport, daddr, hnum, dif,
442 ehashfn: inet_ehashfn);
443 if (result)
444 goto done;
445 }
446
447 hash2 = ipv4_portaddr_hash(net, saddr: daddr, port: hnum);
448 ilb2 = inet_lhash2_bucket(h: hashinfo, hash: hash2);
449
450 result = inet_lhash2_lookup(net, ilb2, skb, doff,
451 saddr, sport, daddr, hnum,
452 dif, sdif);
453 if (result)
454 goto done;
455
456 /* Lookup lhash2 with INADDR_ANY */
457 hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), port: hnum);
458 ilb2 = inet_lhash2_bucket(h: hashinfo, hash: hash2);
459
460 result = inet_lhash2_lookup(net, ilb2, skb, doff,
461 saddr, sport, htonl(INADDR_ANY), hnum,
462 dif, sdif);
463done:
464 if (IS_ERR(ptr: result))
465 return NULL;
466 return result;
467}
468EXPORT_SYMBOL_GPL(__inet_lookup_listener);
469
470/* All sockets share common refcount, but have different destructors */
471void sock_gen_put(struct sock *sk)
472{
473 if (!refcount_dec_and_test(r: &sk->sk_refcnt))
474 return;
475
476 if (sk->sk_state == TCP_TIME_WAIT)
477 inet_twsk_free(tw: inet_twsk(sk));
478 else if (sk->sk_state == TCP_NEW_SYN_RECV)
479 reqsk_free(req: inet_reqsk(sk));
480 else
481 sk_free(sk);
482}
483EXPORT_SYMBOL_GPL(sock_gen_put);
484
485void sock_edemux(struct sk_buff *skb)
486{
487 sock_gen_put(skb->sk);
488}
489EXPORT_SYMBOL(sock_edemux);
490
491struct sock *__inet_lookup_established(struct net *net,
492 struct inet_hashinfo *hashinfo,
493 const __be32 saddr, const __be16 sport,
494 const __be32 daddr, const u16 hnum,
495 const int dif, const int sdif)
496{
497 INET_ADDR_COOKIE(acookie, saddr, daddr);
498 const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
499 struct sock *sk;
500 const struct hlist_nulls_node *node;
501 /* Optimize here for direct hit, only listening connections can
502 * have wildcards anyways.
503 */
504 unsigned int hash = inet_ehashfn(net, daddr, hnum, saddr, sport);
505 unsigned int slot = hash & hashinfo->ehash_mask;
506 struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
507
508begin:
509 sk_nulls_for_each_rcu(sk, node, &head->chain) {
510 if (sk->sk_hash != hash)
511 continue;
512 if (likely(inet_match(net, sk, acookie, ports, dif, sdif))) {
513 if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
514 goto out;
515 if (unlikely(!inet_match(net, sk, acookie,
516 ports, dif, sdif))) {
517 sock_gen_put(sk);
518 goto begin;
519 }
520 goto found;
521 }
522 }
523 /*
524 * if the nulls value we got at the end of this lookup is
525 * not the expected one, we must restart lookup.
526 * We probably met an item that was moved to another chain.
527 */
528 if (get_nulls_value(ptr: node) != slot)
529 goto begin;
530out:
531 sk = NULL;
532found:
533 return sk;
534}
535EXPORT_SYMBOL_GPL(__inet_lookup_established);
536
537/* called with local bh disabled */
538static int __inet_check_established(struct inet_timewait_death_row *death_row,
539 struct sock *sk, __u16 lport,
540 struct inet_timewait_sock **twp)
541{
542 struct inet_hashinfo *hinfo = death_row->hashinfo;
543 struct inet_sock *inet = inet_sk(sk);
544 __be32 daddr = inet->inet_rcv_saddr;
545 __be32 saddr = inet->inet_daddr;
546 int dif = sk->sk_bound_dev_if;
547 struct net *net = sock_net(sk);
548 int sdif = l3mdev_master_ifindex_by_index(net, ifindex: dif);
549 INET_ADDR_COOKIE(acookie, saddr, daddr);
550 const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
551 unsigned int hash = inet_ehashfn(net, daddr, lport,
552 saddr, inet->inet_dport);
553 struct inet_ehash_bucket *head = inet_ehash_bucket(hashinfo: hinfo, hash);
554 spinlock_t *lock = inet_ehash_lockp(hashinfo: hinfo, hash);
555 struct sock *sk2;
556 const struct hlist_nulls_node *node;
557 struct inet_timewait_sock *tw = NULL;
558
559 spin_lock(lock);
560
561 sk_nulls_for_each(sk2, node, &head->chain) {
562 if (sk2->sk_hash != hash)
563 continue;
564
565 if (likely(inet_match(net, sk2, acookie, ports, dif, sdif))) {
566 if (sk2->sk_state == TCP_TIME_WAIT) {
567 tw = inet_twsk(sk: sk2);
568 if (twsk_unique(sk, sktw: sk2, twp))
569 break;
570 }
571 goto not_unique;
572 }
573 }
574
575 /* Must record num and sport now. Otherwise we will see
576 * in hash table socket with a funny identity.
577 */
578 inet->inet_num = lport;
579 inet->inet_sport = htons(lport);
580 sk->sk_hash = hash;
581 WARN_ON(!sk_unhashed(sk));
582 __sk_nulls_add_node_rcu(sk, list: &head->chain);
583 if (tw) {
584 sk_nulls_del_node_init_rcu(sk: (struct sock *)tw);
585 __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
586 }
587 spin_unlock(lock);
588 sock_prot_inuse_add(net: sock_net(sk), prot: sk->sk_prot, val: 1);
589
590 if (twp) {
591 *twp = tw;
592 } else if (tw) {
593 /* Silly. Should hash-dance instead... */
594 inet_twsk_deschedule_put(tw);
595 }
596 return 0;
597
598not_unique:
599 spin_unlock(lock);
600 return -EADDRNOTAVAIL;
601}
602
603static u64 inet_sk_port_offset(const struct sock *sk)
604{
605 const struct inet_sock *inet = inet_sk(sk);
606
607 return secure_ipv4_port_ephemeral(saddr: inet->inet_rcv_saddr,
608 daddr: inet->inet_daddr,
609 dport: inet->inet_dport);
610}
611
612/* Searches for an exsiting socket in the ehash bucket list.
613 * Returns true if found, false otherwise.
614 */
615static bool inet_ehash_lookup_by_sk(struct sock *sk,
616 struct hlist_nulls_head *list)
617{
618 const __portpair ports = INET_COMBINED_PORTS(sk->sk_dport, sk->sk_num);
619 const int sdif = sk->sk_bound_dev_if;
620 const int dif = sk->sk_bound_dev_if;
621 const struct hlist_nulls_node *node;
622 struct net *net = sock_net(sk);
623 struct sock *esk;
624
625 INET_ADDR_COOKIE(acookie, sk->sk_daddr, sk->sk_rcv_saddr);
626
627 sk_nulls_for_each_rcu(esk, node, list) {
628 if (esk->sk_hash != sk->sk_hash)
629 continue;
630 if (sk->sk_family == AF_INET) {
631 if (unlikely(inet_match(net, esk, acookie,
632 ports, dif, sdif))) {
633 return true;
634 }
635 }
636#if IS_ENABLED(CONFIG_IPV6)
637 else if (sk->sk_family == AF_INET6) {
638 if (unlikely(inet6_match(net, esk,
639 &sk->sk_v6_daddr,
640 &sk->sk_v6_rcv_saddr,
641 ports, dif, sdif))) {
642 return true;
643 }
644 }
645#endif
646 }
647 return false;
648}
649
650/* Insert a socket into ehash, and eventually remove another one
651 * (The another one can be a SYN_RECV or TIMEWAIT)
652 * If an existing socket already exists, socket sk is not inserted,
653 * and sets found_dup_sk parameter to true.
654 */
655bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
656{
657 struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
658 struct inet_ehash_bucket *head;
659 struct hlist_nulls_head *list;
660 spinlock_t *lock;
661 bool ret = true;
662
663 WARN_ON_ONCE(!sk_unhashed(sk));
664
665 sk->sk_hash = sk_ehashfn(sk);
666 head = inet_ehash_bucket(hashinfo, hash: sk->sk_hash);
667 list = &head->chain;
668 lock = inet_ehash_lockp(hashinfo, hash: sk->sk_hash);
669
670 spin_lock(lock);
671 if (osk) {
672 WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
673 ret = sk_nulls_del_node_init_rcu(sk: osk);
674 } else if (found_dup_sk) {
675 *found_dup_sk = inet_ehash_lookup_by_sk(sk, list);
676 if (*found_dup_sk)
677 ret = false;
678 }
679
680 if (ret)
681 __sk_nulls_add_node_rcu(sk, list);
682
683 spin_unlock(lock);
684
685 return ret;
686}
687
688bool inet_ehash_nolisten(struct sock *sk, struct sock *osk, bool *found_dup_sk)
689{
690 bool ok = inet_ehash_insert(sk, osk, found_dup_sk);
691
692 if (ok) {
693 sock_prot_inuse_add(net: sock_net(sk), prot: sk->sk_prot, val: 1);
694 } else {
695 this_cpu_inc(*sk->sk_prot->orphan_count);
696 inet_sk_set_state(sk, state: TCP_CLOSE);
697 sock_set_flag(sk, flag: SOCK_DEAD);
698 inet_csk_destroy_sock(sk);
699 }
700 return ok;
701}
702EXPORT_SYMBOL_GPL(inet_ehash_nolisten);
703
704static int inet_reuseport_add_sock(struct sock *sk,
705 struct inet_listen_hashbucket *ilb)
706{
707 struct inet_bind_bucket *tb = inet_csk(sk)->icsk_bind_hash;
708 const struct hlist_nulls_node *node;
709 struct sock *sk2;
710 kuid_t uid = sock_i_uid(sk);
711
712 sk_nulls_for_each_rcu(sk2, node, &ilb->nulls_head) {
713 if (sk2 != sk &&
714 sk2->sk_family == sk->sk_family &&
715 ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
716 sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
717 inet_csk(sk: sk2)->icsk_bind_hash == tb &&
718 sk2->sk_reuseport && uid_eq(left: uid, right: sock_i_uid(sk: sk2)) &&
719 inet_rcv_saddr_equal(sk, sk2, match_wildcard: false))
720 return reuseport_add_sock(sk, sk2,
721 bind_inany: inet_rcv_saddr_any(sk));
722 }
723
724 return reuseport_alloc(sk, bind_inany: inet_rcv_saddr_any(sk));
725}
726
727int __inet_hash(struct sock *sk, struct sock *osk)
728{
729 struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
730 struct inet_listen_hashbucket *ilb2;
731 int err = 0;
732
733 if (sk->sk_state != TCP_LISTEN) {
734 local_bh_disable();
735 inet_ehash_nolisten(sk, osk, NULL);
736 local_bh_enable();
737 return 0;
738 }
739 WARN_ON(!sk_unhashed(sk));
740 ilb2 = inet_lhash2_bucket_sk(h: hashinfo, sk);
741
742 spin_lock(lock: &ilb2->lock);
743 if (sk->sk_reuseport) {
744 err = inet_reuseport_add_sock(sk, ilb: ilb2);
745 if (err)
746 goto unlock;
747 }
748 sock_set_flag(sk, flag: SOCK_RCU_FREE);
749 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
750 sk->sk_family == AF_INET6)
751 __sk_nulls_add_node_tail_rcu(sk, list: &ilb2->nulls_head);
752 else
753 __sk_nulls_add_node_rcu(sk, list: &ilb2->nulls_head);
754 sock_prot_inuse_add(net: sock_net(sk), prot: sk->sk_prot, val: 1);
755unlock:
756 spin_unlock(lock: &ilb2->lock);
757
758 return err;
759}
760EXPORT_SYMBOL(__inet_hash);
761
762int inet_hash(struct sock *sk)
763{
764 int err = 0;
765
766 if (sk->sk_state != TCP_CLOSE)
767 err = __inet_hash(sk, NULL);
768
769 return err;
770}
771EXPORT_SYMBOL_GPL(inet_hash);
772
773void inet_unhash(struct sock *sk)
774{
775 struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
776
777 if (sk_unhashed(sk))
778 return;
779
780 if (sk->sk_state == TCP_LISTEN) {
781 struct inet_listen_hashbucket *ilb2;
782
783 ilb2 = inet_lhash2_bucket_sk(h: hashinfo, sk);
784 /* Don't disable bottom halves while acquiring the lock to
785 * avoid circular locking dependency on PREEMPT_RT.
786 */
787 spin_lock(lock: &ilb2->lock);
788 if (sk_unhashed(sk)) {
789 spin_unlock(lock: &ilb2->lock);
790 return;
791 }
792
793 if (rcu_access_pointer(sk->sk_reuseport_cb))
794 reuseport_stop_listen_sock(sk);
795
796 __sk_nulls_del_node_init_rcu(sk);
797 sock_prot_inuse_add(net: sock_net(sk), prot: sk->sk_prot, val: -1);
798 spin_unlock(lock: &ilb2->lock);
799 } else {
800 spinlock_t *lock = inet_ehash_lockp(hashinfo, hash: sk->sk_hash);
801
802 spin_lock_bh(lock);
803 if (sk_unhashed(sk)) {
804 spin_unlock_bh(lock);
805 return;
806 }
807 __sk_nulls_del_node_init_rcu(sk);
808 sock_prot_inuse_add(net: sock_net(sk), prot: sk->sk_prot, val: -1);
809 spin_unlock_bh(lock);
810 }
811}
812EXPORT_SYMBOL_GPL(inet_unhash);
813
814static bool inet_bind2_bucket_match(const struct inet_bind2_bucket *tb,
815 const struct net *net, unsigned short port,
816 int l3mdev, const struct sock *sk)
817{
818 if (!net_eq(net1: ib2_net(ib: tb), net2: net) || tb->port != port ||
819 tb->l3mdev != l3mdev)
820 return false;
821
822 return inet_bind2_bucket_addr_match(tb2: tb, sk);
823}
824
825bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const struct net *net,
826 unsigned short port, int l3mdev, const struct sock *sk)
827{
828 if (!net_eq(net1: ib2_net(ib: tb), net2: net) || tb->port != port ||
829 tb->l3mdev != l3mdev)
830 return false;
831
832#if IS_ENABLED(CONFIG_IPV6)
833 if (tb->addr_type == IPV6_ADDR_ANY)
834 return true;
835
836 if (tb->addr_type != IPV6_ADDR_MAPPED)
837 return false;
838
839 if (sk->sk_family == AF_INET6 &&
840 !ipv6_addr_v4mapped(a: &sk->sk_v6_rcv_saddr))
841 return false;
842#endif
843 return tb->rcv_saddr == 0;
844}
845
846/* The socket's bhash2 hashbucket spinlock must be held when this is called */
847struct inet_bind2_bucket *
848inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, const struct net *net,
849 unsigned short port, int l3mdev, const struct sock *sk)
850{
851 struct inet_bind2_bucket *bhash2 = NULL;
852
853 inet_bind_bucket_for_each(bhash2, &head->chain)
854 if (inet_bind2_bucket_match(tb: bhash2, net, port, l3mdev, sk))
855 break;
856
857 return bhash2;
858}
859
860struct inet_bind_hashbucket *
861inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port)
862{
863 struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
864 u32 hash;
865
866#if IS_ENABLED(CONFIG_IPV6)
867 if (sk->sk_family == AF_INET6)
868 hash = ipv6_portaddr_hash(net, addr6: &in6addr_any, port);
869 else
870#endif
871 hash = ipv4_portaddr_hash(net, saddr: 0, port);
872
873 return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
874}
875
876static void inet_update_saddr(struct sock *sk, void *saddr, int family)
877{
878 if (family == AF_INET) {
879 inet_sk(sk)->inet_saddr = *(__be32 *)saddr;
880 sk_rcv_saddr_set(sk, inet_sk(sk)->inet_saddr);
881 }
882#if IS_ENABLED(CONFIG_IPV6)
883 else {
884 sk->sk_v6_rcv_saddr = *(struct in6_addr *)saddr;
885 }
886#endif
887}
888
889static int __inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family, bool reset)
890{
891 struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
892 struct inet_bind_hashbucket *head, *head2;
893 struct inet_bind2_bucket *tb2, *new_tb2;
894 int l3mdev = inet_sk_bound_l3mdev(sk);
895 int port = inet_sk(sk)->inet_num;
896 struct net *net = sock_net(sk);
897 int bhash;
898
899 if (!inet_csk(sk)->icsk_bind2_hash) {
900 /* Not bind()ed before. */
901 if (reset)
902 inet_reset_saddr(sk);
903 else
904 inet_update_saddr(sk, saddr, family);
905
906 return 0;
907 }
908
909 /* Allocate a bind2 bucket ahead of time to avoid permanently putting
910 * the bhash2 table in an inconsistent state if a new tb2 bucket
911 * allocation fails.
912 */
913 new_tb2 = kmem_cache_alloc(cachep: hinfo->bind2_bucket_cachep, GFP_ATOMIC);
914 if (!new_tb2) {
915 if (reset) {
916 /* The (INADDR_ANY, port) bucket might have already
917 * been freed, then we cannot fixup icsk_bind2_hash,
918 * so we give up and unlink sk from bhash/bhash2 not
919 * to leave inconsistency in bhash2.
920 */
921 inet_put_port(sk);
922 inet_reset_saddr(sk);
923 }
924
925 return -ENOMEM;
926 }
927
928 bhash = inet_bhashfn(net, lport: port, bhash_size: hinfo->bhash_size);
929 head = &hinfo->bhash[bhash];
930 head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
931
932 /* If we change saddr locklessly, another thread
933 * iterating over bhash might see corrupted address.
934 */
935 spin_lock_bh(lock: &head->lock);
936
937 spin_lock(lock: &head2->lock);
938 __sk_del_bind_node(sk);
939 inet_bind2_bucket_destroy(cachep: hinfo->bind2_bucket_cachep, tb: inet_csk(sk)->icsk_bind2_hash);
940 spin_unlock(lock: &head2->lock);
941
942 if (reset)
943 inet_reset_saddr(sk);
944 else
945 inet_update_saddr(sk, saddr, family);
946
947 head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
948
949 spin_lock(lock: &head2->lock);
950 tb2 = inet_bind2_bucket_find(head: head2, net, port, l3mdev, sk);
951 if (!tb2) {
952 tb2 = new_tb2;
953 inet_bind2_bucket_init(tb2, net, head: head2, tb: inet_csk(sk)->icsk_bind_hash, sk);
954 }
955 inet_csk(sk)->icsk_bind2_hash = tb2;
956 sk_add_bind_node(sk, list: &tb2->owners);
957 spin_unlock(lock: &head2->lock);
958
959 spin_unlock_bh(lock: &head->lock);
960
961 if (tb2 != new_tb2)
962 kmem_cache_free(s: hinfo->bind2_bucket_cachep, objp: new_tb2);
963
964 return 0;
965}
966
967int inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family)
968{
969 return __inet_bhash2_update_saddr(sk, saddr, family, reset: false);
970}
971EXPORT_SYMBOL_GPL(inet_bhash2_update_saddr);
972
973void inet_bhash2_reset_saddr(struct sock *sk)
974{
975 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
976 __inet_bhash2_update_saddr(sk, NULL, family: 0, reset: true);
977}
978EXPORT_SYMBOL_GPL(inet_bhash2_reset_saddr);
979
980/* RFC 6056 3.3.4. Algorithm 4: Double-Hash Port Selection Algorithm
981 * Note that we use 32bit integers (vs RFC 'short integers')
982 * because 2^16 is not a multiple of num_ephemeral and this
983 * property might be used by clever attacker.
984 *
985 * RFC claims using TABLE_LENGTH=10 buckets gives an improvement, though
986 * attacks were since demonstrated, thus we use 65536 by default instead
987 * to really give more isolation and privacy, at the expense of 256kB
988 * of kernel memory.
989 */
990#define INET_TABLE_PERTURB_SIZE (1 << CONFIG_INET_TABLE_PERTURB_ORDER)
991static u32 *table_perturb;
992
993int __inet_hash_connect(struct inet_timewait_death_row *death_row,
994 struct sock *sk, u64 port_offset,
995 int (*check_established)(struct inet_timewait_death_row *,
996 struct sock *, __u16, struct inet_timewait_sock **))
997{
998 struct inet_hashinfo *hinfo = death_row->hashinfo;
999 struct inet_bind_hashbucket *head, *head2;
1000 struct inet_timewait_sock *tw = NULL;
1001 int port = inet_sk(sk)->inet_num;
1002 struct net *net = sock_net(sk);
1003 struct inet_bind2_bucket *tb2;
1004 struct inet_bind_bucket *tb;
1005 bool tb_created = false;
1006 u32 remaining, offset;
1007 int ret, i, low, high;
1008 bool local_ports;
1009 int step, l3mdev;
1010 u32 index;
1011
1012 if (port) {
1013 local_bh_disable();
1014 ret = check_established(death_row, sk, port, NULL);
1015 local_bh_enable();
1016 return ret;
1017 }
1018
1019 l3mdev = inet_sk_bound_l3mdev(sk);
1020
1021 local_ports = inet_sk_get_local_port_range(sk, low: &low, high: &high);
1022 step = local_ports ? 1 : 2;
1023
1024 high++; /* [32768, 60999] -> [32768, 61000[ */
1025 remaining = high - low;
1026 if (!local_ports && remaining > 1)
1027 remaining &= ~1U;
1028
1029 get_random_sleepable_once(table_perturb,
1030 INET_TABLE_PERTURB_SIZE * sizeof(*table_perturb));
1031 index = port_offset & (INET_TABLE_PERTURB_SIZE - 1);
1032
1033 offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32);
1034 offset %= remaining;
1035
1036 /* In first pass we try ports of @low parity.
1037 * inet_csk_get_port() does the opposite choice.
1038 */
1039 if (!local_ports)
1040 offset &= ~1U;
1041other_parity_scan:
1042 port = low + offset;
1043 for (i = 0; i < remaining; i += step, port += step) {
1044 if (unlikely(port >= high))
1045 port -= remaining;
1046 if (inet_is_local_reserved_port(net, port))
1047 continue;
1048 head = &hinfo->bhash[inet_bhashfn(net, lport: port,
1049 bhash_size: hinfo->bhash_size)];
1050 spin_lock_bh(lock: &head->lock);
1051
1052 /* Does not bother with rcv_saddr checks, because
1053 * the established check is already unique enough.
1054 */
1055 inet_bind_bucket_for_each(tb, &head->chain) {
1056 if (inet_bind_bucket_match(tb, net, port, l3mdev)) {
1057 if (tb->fastreuse >= 0 ||
1058 tb->fastreuseport >= 0)
1059 goto next_port;
1060 WARN_ON(hlist_empty(&tb->bhash2));
1061 if (!check_established(death_row, sk,
1062 port, &tw))
1063 goto ok;
1064 goto next_port;
1065 }
1066 }
1067
1068 tb = inet_bind_bucket_create(cachep: hinfo->bind_bucket_cachep,
1069 net, head, snum: port, l3mdev);
1070 if (!tb) {
1071 spin_unlock_bh(lock: &head->lock);
1072 return -ENOMEM;
1073 }
1074 tb_created = true;
1075 tb->fastreuse = -1;
1076 tb->fastreuseport = -1;
1077 goto ok;
1078next_port:
1079 spin_unlock_bh(lock: &head->lock);
1080 cond_resched();
1081 }
1082
1083 if (!local_ports) {
1084 offset++;
1085 if ((offset & 1) && remaining > 1)
1086 goto other_parity_scan;
1087 }
1088 return -EADDRNOTAVAIL;
1089
1090ok:
1091 /* Find the corresponding tb2 bucket since we need to
1092 * add the socket to the bhash2 table as well
1093 */
1094 head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
1095 spin_lock(lock: &head2->lock);
1096
1097 tb2 = inet_bind2_bucket_find(head: head2, net, port, l3mdev, sk);
1098 if (!tb2) {
1099 tb2 = inet_bind2_bucket_create(cachep: hinfo->bind2_bucket_cachep, net,
1100 head: head2, tb, sk);
1101 if (!tb2)
1102 goto error;
1103 }
1104
1105 /* Here we want to add a little bit of randomness to the next source
1106 * port that will be chosen. We use a max() with a random here so that
1107 * on low contention the randomness is maximal and on high contention
1108 * it may be inexistent.
1109 */
1110 i = max_t(int, i, get_random_u32_below(8) * step);
1111 WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + step);
1112
1113 /* Head lock still held and bh's disabled */
1114 inet_bind_hash(sk, tb, tb2, port);
1115
1116 if (sk_unhashed(sk)) {
1117 inet_sk(sk)->inet_sport = htons(port);
1118 inet_ehash_nolisten(sk, (struct sock *)tw, NULL);
1119 }
1120 if (tw)
1121 inet_twsk_bind_unhash(tw, hashinfo: hinfo);
1122
1123 spin_unlock(lock: &head2->lock);
1124 spin_unlock(lock: &head->lock);
1125
1126 if (tw)
1127 inet_twsk_deschedule_put(tw);
1128 local_bh_enable();
1129 return 0;
1130
1131error:
1132 if (sk_hashed(sk)) {
1133 spinlock_t *lock = inet_ehash_lockp(hashinfo: hinfo, hash: sk->sk_hash);
1134
1135 sock_prot_inuse_add(net, prot: sk->sk_prot, val: -1);
1136
1137 spin_lock(lock);
1138 __sk_nulls_del_node_init_rcu(sk);
1139 spin_unlock(lock);
1140
1141 sk->sk_hash = 0;
1142 inet_sk(sk)->inet_sport = 0;
1143 inet_sk(sk)->inet_num = 0;
1144
1145 if (tw)
1146 inet_twsk_bind_unhash(tw, hashinfo: hinfo);
1147 }
1148
1149 spin_unlock(lock: &head2->lock);
1150 if (tb_created)
1151 inet_bind_bucket_destroy(cachep: hinfo->bind_bucket_cachep, tb);
1152 spin_unlock(lock: &head->lock);
1153
1154 if (tw)
1155 inet_twsk_deschedule_put(tw);
1156
1157 local_bh_enable();
1158
1159 return -ENOMEM;
1160}
1161
1162/*
1163 * Bind a port for a connect operation and hash it.
1164 */
1165int inet_hash_connect(struct inet_timewait_death_row *death_row,
1166 struct sock *sk)
1167{
1168 u64 port_offset = 0;
1169
1170 if (!inet_sk(sk)->inet_num)
1171 port_offset = inet_sk_port_offset(sk);
1172 return __inet_hash_connect(death_row, sk, port_offset,
1173 check_established: __inet_check_established);
1174}
1175EXPORT_SYMBOL_GPL(inet_hash_connect);
1176
1177static void init_hashinfo_lhash2(struct inet_hashinfo *h)
1178{
1179 int i;
1180
1181 for (i = 0; i <= h->lhash2_mask; i++) {
1182 spin_lock_init(&h->lhash2[i].lock);
1183 INIT_HLIST_NULLS_HEAD(&h->lhash2[i].nulls_head,
1184 i + LISTENING_NULLS_BASE);
1185 }
1186}
1187
1188void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
1189 unsigned long numentries, int scale,
1190 unsigned long low_limit,
1191 unsigned long high_limit)
1192{
1193 h->lhash2 = alloc_large_system_hash(tablename: name,
1194 bucketsize: sizeof(*h->lhash2),
1195 numentries,
1196 scale,
1197 flags: 0,
1198 NULL,
1199 hash_mask: &h->lhash2_mask,
1200 low_limit,
1201 high_limit);
1202 init_hashinfo_lhash2(h);
1203
1204 /* this one is used for source ports of outgoing connections */
1205 table_perturb = alloc_large_system_hash(tablename: "Table-perturb",
1206 bucketsize: sizeof(*table_perturb),
1207 INET_TABLE_PERTURB_SIZE,
1208 scale: 0, flags: 0, NULL, NULL,
1209 INET_TABLE_PERTURB_SIZE,
1210 INET_TABLE_PERTURB_SIZE);
1211}
1212
1213int inet_hashinfo2_init_mod(struct inet_hashinfo *h)
1214{
1215 h->lhash2 = kmalloc_array(INET_LHTABLE_SIZE, size: sizeof(*h->lhash2), GFP_KERNEL);
1216 if (!h->lhash2)
1217 return -ENOMEM;
1218
1219 h->lhash2_mask = INET_LHTABLE_SIZE - 1;
1220 /* INET_LHTABLE_SIZE must be a power of 2 */
1221 BUG_ON(INET_LHTABLE_SIZE & h->lhash2_mask);
1222
1223 init_hashinfo_lhash2(h);
1224 return 0;
1225}
1226EXPORT_SYMBOL_GPL(inet_hashinfo2_init_mod);
1227
1228int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
1229{
1230 unsigned int locksz = sizeof(spinlock_t);
1231 unsigned int i, nblocks = 1;
1232
1233 if (locksz != 0) {
1234 /* allocate 2 cache lines or at least one spinlock per cpu */
1235 nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
1236 nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
1237
1238 /* no more locks than number of hash buckets */
1239 nblocks = min(nblocks, hashinfo->ehash_mask + 1);
1240
1241 hashinfo->ehash_locks = kvmalloc_array(n: nblocks, size: locksz, GFP_KERNEL);
1242 if (!hashinfo->ehash_locks)
1243 return -ENOMEM;
1244
1245 for (i = 0; i < nblocks; i++)
1246 spin_lock_init(&hashinfo->ehash_locks[i]);
1247 }
1248 hashinfo->ehash_locks_mask = nblocks - 1;
1249 return 0;
1250}
1251EXPORT_SYMBOL_GPL(inet_ehash_locks_alloc);
1252
1253struct inet_hashinfo *inet_pernet_hashinfo_alloc(struct inet_hashinfo *hashinfo,
1254 unsigned int ehash_entries)
1255{
1256 struct inet_hashinfo *new_hashinfo;
1257 int i;
1258
1259 new_hashinfo = kmemdup(p: hashinfo, size: sizeof(*hashinfo), GFP_KERNEL);
1260 if (!new_hashinfo)
1261 goto err;
1262
1263 new_hashinfo->ehash = vmalloc_huge(size: ehash_entries * sizeof(struct inet_ehash_bucket),
1264 GFP_KERNEL_ACCOUNT);
1265 if (!new_hashinfo->ehash)
1266 goto free_hashinfo;
1267
1268 new_hashinfo->ehash_mask = ehash_entries - 1;
1269
1270 if (inet_ehash_locks_alloc(new_hashinfo))
1271 goto free_ehash;
1272
1273 for (i = 0; i < ehash_entries; i++)
1274 INIT_HLIST_NULLS_HEAD(&new_hashinfo->ehash[i].chain, i);
1275
1276 new_hashinfo->pernet = true;
1277
1278 return new_hashinfo;
1279
1280free_ehash:
1281 vfree(addr: new_hashinfo->ehash);
1282free_hashinfo:
1283 kfree(objp: new_hashinfo);
1284err:
1285 return NULL;
1286}
1287EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_alloc);
1288
1289void inet_pernet_hashinfo_free(struct inet_hashinfo *hashinfo)
1290{
1291 if (!hashinfo->pernet)
1292 return;
1293
1294 inet_ehash_locks_free(hashinfo);
1295 vfree(addr: hashinfo->ehash);
1296 kfree(objp: hashinfo);
1297}
1298EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_free);
1299

source code of linux/net/ipv4/inet_hashtables.c