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(&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(&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(&tb->node, &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(&tb->bhash2)) {
  90		__hlist_del(&tb->node);
  91		kmem_cache_free(cachep, 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(ib_net(tb), 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(&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(&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(sk->sk_rcv_saddr, &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(&tb2->node, &head->chain);
 125	hlist_add_head(&tb2->bhash_node, &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(&tb->owners)) {
 146		__hlist_del(&tb->node);
 147		__hlist_del(&tb->bhash_node);
 148		kmem_cache_free(cachep, 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(&tb2->v6_rcv_saddr, &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, &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, hashinfo->bhash_size);
 186	head = &hashinfo->bhash[bhash];
 187	head2 = inet_bhashfn_portaddr(hashinfo, sk, net, inet_sk(sk)->inet_num);
 188
 189	spin_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(&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(hashinfo->bind2_bucket_cachep, tb2);
 201	}
 202	spin_unlock(&head2->lock);
 203
 204	inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);
 205	spin_unlock(&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, port, table->bhash_size);
 229	head = &table->bhash[bhash];
 230	head2 = inet_bhashfn_portaddr(table, child, net, port);
 231
 232	spin_lock(&head->lock);
 233	spin_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(&head2->lock);
 238		spin_unlock(&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(table->bind_bucket_cachep,
 255						     net, head, port, l3mdev);
 256			if (!tb) {
 257				spin_unlock(&head2->lock);
 258				spin_unlock(&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, child)) {
 267		l3mdev = inet_sk_bound_l3mdev(sk);
 268
 269bhash2_find:
 270		tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, child);
 271		if (!tb2) {
 272			tb2 = inet_bind2_bucket_create(table->bind2_bucket_cachep,
 273						       net, head2, tb, child);
 274			if (!tb2)
 275				goto error;
 276		}
 277	}
 278	if (update_fastreuse)
 279		inet_csk_update_fastreuse(tb, child);
 280	inet_bind_hash(child, tb, tb2, port);
 281	spin_unlock(&head2->lock);
 282	spin_unlock(&head->lock);
 283
 284	return 0;
 285
 286error:
 287	if (created_inet_bind_bucket)
 288		inet_bind_bucket_destroy(table->bind_bucket_cachep, tb);
 289	spin_unlock(&head2->lock);
 290	spin_unlock(&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(sock_net(sk),
 303					  &sk->sk_v6_rcv_saddr,
 304					  inet_sk(sk)->inet_num);
 305	else
 306#endif
 307		hash = ipv4_portaddr_hash(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, const 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(sock_net(sk), 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, 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(const 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, phash, skb, 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(const 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(const 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, hnum, dif, &sk);
 416	if (no_reuseport || IS_ERR_OR_NULL(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(const 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						   inet_ehashfn);
 443		if (result)
 444			goto done;
 445	}
 446
 447	hash2 = ipv4_portaddr_hash(net, daddr, hnum);
 448	ilb2 = inet_lhash2_bucket(hashinfo, 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), hnum);
 458	ilb2 = inet_lhash2_bucket(hashinfo, 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(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(&sk->sk_refcnt))
 474		return;
 475
 476	if (sk->sk_state == TCP_TIME_WAIT)
 477		inet_twsk_free(inet_twsk(sk));
 478	else if (sk->sk_state == TCP_NEW_SYN_RECV)
 479		reqsk_free(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(const 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(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, 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(hinfo, hash);
 554	spinlock_t *lock = inet_ehash_lockp(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(sk2);
 568				if (sk->sk_protocol == IPPROTO_TCP &&
 569				    tcp_twsk_unique(sk, sk2, twp))
 570					break;
 571			}
 572			goto not_unique;
 573		}
 574	}
 
 
 
 
 
 
 
 
 575
 
 576	/* Must record num and sport now. Otherwise we will see
 577	 * in hash table socket with a funny identity.
 578	 */
 579	inet->inet_num = lport;
 580	inet->inet_sport = htons(lport);
 581	sk->sk_hash = hash;
 582	WARN_ON(!sk_unhashed(sk));
 583	__sk_nulls_add_node_rcu(sk, &head->chain);
 584	if (tw) {
 585		sk_nulls_del_node_init_rcu((struct sock *)tw);
 586		__NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
 587	}
 588	spin_unlock(lock);
 
 
 589	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 590
 591	if (twp) {
 592		*twp = tw;
 593	} else if (tw) {
 594		/* Silly. Should hash-dance instead... */
 595		inet_twsk_deschedule_put(tw);
 
 
 596	}
 597	return 0;
 598
 599not_unique:
 600	spin_unlock(lock);
 601	return -EADDRNOTAVAIL;
 602}
 603
 604static u64 inet_sk_port_offset(const struct sock *sk)
 605{
 606	const struct inet_sock *inet = inet_sk(sk);
 607
 608	return secure_ipv4_port_ephemeral(inet->inet_rcv_saddr,
 609					  inet->inet_daddr,
 610					  inet->inet_dport);
 611}
 612
 613/* Searches for an exsiting socket in the ehash bucket list.
 614 * Returns true if found, false otherwise.
 615 */
 616static bool inet_ehash_lookup_by_sk(struct sock *sk,
 617				    struct hlist_nulls_head *list)
 618{
 619	const __portpair ports = INET_COMBINED_PORTS(sk->sk_dport, sk->sk_num);
 620	const int sdif = sk->sk_bound_dev_if;
 621	const int dif = sk->sk_bound_dev_if;
 622	const struct hlist_nulls_node *node;
 623	struct net *net = sock_net(sk);
 624	struct sock *esk;
 625
 626	INET_ADDR_COOKIE(acookie, sk->sk_daddr, sk->sk_rcv_saddr);
 627
 628	sk_nulls_for_each_rcu(esk, node, list) {
 629		if (esk->sk_hash != sk->sk_hash)
 630			continue;
 631		if (sk->sk_family == AF_INET) {
 632			if (unlikely(inet_match(net, esk, acookie,
 633						ports, dif, sdif))) {
 634				return true;
 635			}
 636		}
 637#if IS_ENABLED(CONFIG_IPV6)
 638		else if (sk->sk_family == AF_INET6) {
 639			if (unlikely(inet6_match(net, esk,
 640						 &sk->sk_v6_daddr,
 641						 &sk->sk_v6_rcv_saddr,
 642						 ports, dif, sdif))) {
 643				return true;
 644			}
 645		}
 646#endif
 647	}
 648	return false;
 649}
 650
 651/* Insert a socket into ehash, and eventually remove another one
 652 * (The another one can be a SYN_RECV or TIMEWAIT)
 653 * If an existing socket already exists, socket sk is not inserted,
 654 * and sets found_dup_sk parameter to true.
 655 */
 656bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 657{
 658	struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 659	struct inet_ehash_bucket *head;
 660	struct hlist_nulls_head *list;
 661	spinlock_t *lock;
 662	bool ret = true;
 
 663
 664	WARN_ON_ONCE(!sk_unhashed(sk));
 665
 666	sk->sk_hash = sk_ehashfn(sk);
 667	head = inet_ehash_bucket(hashinfo, sk->sk_hash);
 668	list = &head->chain;
 669	lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 670
 671	spin_lock(lock);
 672	if (osk) {
 673		WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
 674		ret = sk_nulls_del_node_init_rcu(osk);
 675	} else if (found_dup_sk) {
 676		*found_dup_sk = inet_ehash_lookup_by_sk(sk, list);
 677		if (*found_dup_sk)
 678			ret = false;
 679	}
 680
 681	if (ret)
 682		__sk_nulls_add_node_rcu(sk, list);
 683
 684	spin_unlock(lock);
 685
 686	return ret;
 687}
 
 688
 689bool inet_ehash_nolisten(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 690{
 691	bool ok = inet_ehash_insert(sk, osk, found_dup_sk);
 
 692
 693	if (ok) {
 694		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 695	} else {
 696		this_cpu_inc(*sk->sk_prot->orphan_count);
 697		inet_sk_set_state(sk, TCP_CLOSE);
 698		sock_set_flag(sk, SOCK_DEAD);
 699		inet_csk_destroy_sock(sk);
 700	}
 701	return ok;
 702}
 703EXPORT_SYMBOL_GPL(inet_ehash_nolisten);
 704
 705static int inet_reuseport_add_sock(struct sock *sk,
 706				   struct inet_listen_hashbucket *ilb)
 707{
 708	struct inet_bind_bucket *tb = inet_csk(sk)->icsk_bind_hash;
 709	const struct hlist_nulls_node *node;
 710	struct sock *sk2;
 711	kuid_t uid = sock_i_uid(sk);
 712
 713	sk_nulls_for_each_rcu(sk2, node, &ilb->nulls_head) {
 714		if (sk2 != sk &&
 715		    sk2->sk_family == sk->sk_family &&
 716		    ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
 717		    sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
 718		    inet_csk(sk2)->icsk_bind_hash == tb &&
 719		    sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
 720		    inet_rcv_saddr_equal(sk, sk2, false))
 721			return reuseport_add_sock(sk, sk2,
 722						  inet_rcv_saddr_any(sk));
 723	}
 724
 725	return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
 
 
 
 726}
 727
 728int __inet_hash(struct sock *sk, struct sock *osk)
 729{
 730	struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 731	struct inet_listen_hashbucket *ilb2;
 732	int err = 0;
 733
 734	if (sk->sk_state != TCP_LISTEN) {
 735		local_bh_disable();
 736		inet_ehash_nolisten(sk, osk, NULL);
 737		local_bh_enable();
 738		return 0;
 739	}
 740	WARN_ON(!sk_unhashed(sk));
 741	ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 742
 743	spin_lock(&ilb2->lock);
 744	if (sk->sk_reuseport) {
 745		err = inet_reuseport_add_sock(sk, ilb2);
 746		if (err)
 747			goto unlock;
 748	}
 749	sock_set_flag(sk, SOCK_RCU_FREE);
 750	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 751		sk->sk_family == AF_INET6)
 752		__sk_nulls_add_node_tail_rcu(sk, &ilb2->nulls_head);
 753	else
 754		__sk_nulls_add_node_rcu(sk, &ilb2->nulls_head);
 755	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 756unlock:
 757	spin_unlock(&ilb2->lock);
 758
 759	return err;
 760}
 761EXPORT_SYMBOL(__inet_hash);
 762
 763int inet_hash(struct sock *sk)
 764{
 765	int err = 0;
 766
 767	if (sk->sk_state != TCP_CLOSE)
 768		err = __inet_hash(sk, NULL);
 769
 770	return err;
 771}
 772EXPORT_SYMBOL_GPL(inet_hash);
 773
 774void inet_unhash(struct sock *sk)
 775{
 776	struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 
 
 777
 778	if (sk_unhashed(sk))
 779		return;
 780
 781	if (sk->sk_state == TCP_LISTEN) {
 782		struct inet_listen_hashbucket *ilb2;
 783
 784		ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 785		/* Don't disable bottom halves while acquiring the lock to
 786		 * avoid circular locking dependency on PREEMPT_RT.
 787		 */
 788		spin_lock(&ilb2->lock);
 789		if (sk_unhashed(sk)) {
 790			spin_unlock(&ilb2->lock);
 791			return;
 792		}
 793
 794		if (rcu_access_pointer(sk->sk_reuseport_cb))
 795			reuseport_stop_listen_sock(sk);
 796
 797		__sk_nulls_del_node_init_rcu(sk);
 798		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 799		spin_unlock(&ilb2->lock);
 800	} else {
 801		spinlock_t *lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 802
 803		spin_lock_bh(lock);
 804		if (sk_unhashed(sk)) {
 805			spin_unlock_bh(lock);
 806			return;
 807		}
 808		__sk_nulls_del_node_init_rcu(sk);
 809		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 810		spin_unlock_bh(lock);
 811	}
 812}
 813EXPORT_SYMBOL_GPL(inet_unhash);
 814
 815static bool inet_bind2_bucket_match(const struct inet_bind2_bucket *tb,
 816				    const struct net *net, unsigned short port,
 817				    int l3mdev, const struct sock *sk)
 818{
 819	if (!net_eq(ib2_net(tb), net) || tb->port != port ||
 820	    tb->l3mdev != l3mdev)
 821		return false;
 822
 823	return inet_bind2_bucket_addr_match(tb, sk);
 824}
 825
 826bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const struct net *net,
 827				      unsigned short port, int l3mdev, const struct sock *sk)
 828{
 829	if (!net_eq(ib2_net(tb), net) || tb->port != port ||
 830	    tb->l3mdev != l3mdev)
 831		return false;
 832
 833#if IS_ENABLED(CONFIG_IPV6)
 834	if (tb->addr_type == IPV6_ADDR_ANY)
 835		return true;
 836
 837	if (tb->addr_type != IPV6_ADDR_MAPPED)
 838		return false;
 839
 840	if (sk->sk_family == AF_INET6 &&
 841	    !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
 842		return false;
 843#endif
 844	return tb->rcv_saddr == 0;
 845}
 846
 847/* The socket's bhash2 hashbucket spinlock must be held when this is called */
 848struct inet_bind2_bucket *
 849inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, const struct net *net,
 850		       unsigned short port, int l3mdev, const struct sock *sk)
 851{
 852	struct inet_bind2_bucket *bhash2 = NULL;
 853
 854	inet_bind_bucket_for_each(bhash2, &head->chain)
 855		if (inet_bind2_bucket_match(bhash2, net, port, l3mdev, sk))
 856			break;
 857
 858	return bhash2;
 859}
 860
 861struct inet_bind_hashbucket *
 862inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port)
 863{
 864	struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 865	u32 hash;
 866
 867#if IS_ENABLED(CONFIG_IPV6)
 868	if (sk->sk_family == AF_INET6)
 869		hash = ipv6_portaddr_hash(net, &in6addr_any, port);
 870	else
 871#endif
 872		hash = ipv4_portaddr_hash(net, 0, port);
 873
 874	return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
 875}
 876
 877static void inet_update_saddr(struct sock *sk, void *saddr, int family)
 878{
 879	if (family == AF_INET) {
 880		inet_sk(sk)->inet_saddr = *(__be32 *)saddr;
 881		sk_rcv_saddr_set(sk, inet_sk(sk)->inet_saddr);
 882	}
 883#if IS_ENABLED(CONFIG_IPV6)
 884	else {
 885		sk->sk_v6_rcv_saddr = *(struct in6_addr *)saddr;
 886	}
 887#endif
 888}
 889
 890static int __inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family, bool reset)
 891{
 892	struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 893	struct inet_bind_hashbucket *head, *head2;
 894	struct inet_bind2_bucket *tb2, *new_tb2;
 895	int l3mdev = inet_sk_bound_l3mdev(sk);
 896	int port = inet_sk(sk)->inet_num;
 897	struct net *net = sock_net(sk);
 898	int bhash;
 899
 900	if (!inet_csk(sk)->icsk_bind2_hash) {
 901		/* Not bind()ed before. */
 902		if (reset)
 903			inet_reset_saddr(sk);
 904		else
 905			inet_update_saddr(sk, saddr, family);
 906
 907		return 0;
 908	}
 909
 910	/* Allocate a bind2 bucket ahead of time to avoid permanently putting
 911	 * the bhash2 table in an inconsistent state if a new tb2 bucket
 912	 * allocation fails.
 913	 */
 914	new_tb2 = kmem_cache_alloc(hinfo->bind2_bucket_cachep, GFP_ATOMIC);
 915	if (!new_tb2) {
 916		if (reset) {
 917			/* The (INADDR_ANY, port) bucket might have already
 918			 * been freed, then we cannot fixup icsk_bind2_hash,
 919			 * so we give up and unlink sk from bhash/bhash2 not
 920			 * to leave inconsistency in bhash2.
 921			 */
 922			inet_put_port(sk);
 923			inet_reset_saddr(sk);
 924		}
 925
 926		return -ENOMEM;
 927	}
 928
 929	bhash = inet_bhashfn(net, port, hinfo->bhash_size);
 930	head = &hinfo->bhash[bhash];
 931	head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 932
 933	/* If we change saddr locklessly, another thread
 934	 * iterating over bhash might see corrupted address.
 935	 */
 936	spin_lock_bh(&head->lock);
 937
 938	spin_lock(&head2->lock);
 939	__sk_del_bind_node(sk);
 940	inet_bind2_bucket_destroy(hinfo->bind2_bucket_cachep, inet_csk(sk)->icsk_bind2_hash);
 941	spin_unlock(&head2->lock);
 942
 943	if (reset)
 944		inet_reset_saddr(sk);
 945	else
 946		inet_update_saddr(sk, saddr, family);
 947
 948	head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 949
 950	spin_lock(&head2->lock);
 951	tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
 952	if (!tb2) {
 953		tb2 = new_tb2;
 954		inet_bind2_bucket_init(tb2, net, head2, inet_csk(sk)->icsk_bind_hash, sk);
 955	}
 956	inet_csk(sk)->icsk_bind2_hash = tb2;
 957	sk_add_bind_node(sk, &tb2->owners);
 958	spin_unlock(&head2->lock);
 959
 960	spin_unlock_bh(&head->lock);
 961
 962	if (tb2 != new_tb2)
 963		kmem_cache_free(hinfo->bind2_bucket_cachep, new_tb2);
 964
 965	return 0;
 966}
 967
 968int inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family)
 969{
 970	return __inet_bhash2_update_saddr(sk, saddr, family, false);
 971}
 972EXPORT_SYMBOL_GPL(inet_bhash2_update_saddr);
 973
 974void inet_bhash2_reset_saddr(struct sock *sk)
 975{
 976	if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
 977		__inet_bhash2_update_saddr(sk, NULL, 0, true);
 978}
 979EXPORT_SYMBOL_GPL(inet_bhash2_reset_saddr);
 980
 981/* RFC 6056 3.3.4.  Algorithm 4: Double-Hash Port Selection Algorithm
 982 * Note that we use 32bit integers (vs RFC 'short integers')
 983 * because 2^16 is not a multiple of num_ephemeral and this
 984 * property might be used by clever attacker.
 985 *
 986 * RFC claims using TABLE_LENGTH=10 buckets gives an improvement, though
 987 * attacks were since demonstrated, thus we use 65536 by default instead
 988 * to really give more isolation and privacy, at the expense of 256kB
 989 * of kernel memory.
 990 */
 991#define INET_TABLE_PERTURB_SIZE (1 << CONFIG_INET_TABLE_PERTURB_ORDER)
 992static u32 *table_perturb;
 993
 994int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 995		struct sock *sk, u64 port_offset,
 996		int (*check_established)(struct inet_timewait_death_row *,
 997			struct sock *, __u16, struct inet_timewait_sock **))
 
 998{
 999	struct inet_hashinfo *hinfo = death_row->hashinfo;
1000	struct inet_bind_hashbucket *head, *head2;
1001	struct inet_timewait_sock *tw = NULL;
1002	int port = inet_sk(sk)->inet_num;
1003	struct net *net = sock_net(sk);
1004	struct inet_bind2_bucket *tb2;
1005	struct inet_bind_bucket *tb;
1006	bool tb_created = false;
1007	u32 remaining, offset;
1008	int ret, i, low, high;
1009	bool local_ports;
1010	int step, l3mdev;
1011	u32 index;
1012
1013	if (port) {
1014		local_bh_disable();
1015		ret = check_established(death_row, sk, port, NULL);
1016		local_bh_enable();
1017		return ret;
1018	}
1019
1020	l3mdev = inet_sk_bound_l3mdev(sk);
1021
1022	local_ports = inet_sk_get_local_port_range(sk, &low, &high);
1023	step = local_ports ? 1 : 2;
1024
1025	high++; /* [32768, 60999] -> [32768, 61000[ */
1026	remaining = high - low;
1027	if (!local_ports && remaining > 1)
1028		remaining &= ~1U;
1029
1030	get_random_sleepable_once(table_perturb,
1031				  INET_TABLE_PERTURB_SIZE * sizeof(*table_perturb));
1032	index = port_offset & (INET_TABLE_PERTURB_SIZE - 1);
 
 
 
1033
1034	offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32);
1035	offset %= remaining;
1036
1037	/* In first pass we try ports of @low parity.
1038	 * inet_csk_get_port() does the opposite choice.
1039	 */
1040	if (!local_ports)
1041		offset &= ~1U;
1042other_parity_scan:
1043	port = low + offset;
1044	for (i = 0; i < remaining; i += step, port += step) {
1045		if (unlikely(port >= high))
1046			port -= remaining;
1047		if (inet_is_local_reserved_port(net, port))
1048			continue;
1049		head = &hinfo->bhash[inet_bhashfn(net, port,
1050						  hinfo->bhash_size)];
1051		spin_lock_bh(&head->lock);
1052
1053		/* Does not bother with rcv_saddr checks, because
1054		 * the established check is already unique enough.
1055		 */
1056		inet_bind_bucket_for_each(tb, &head->chain) {
1057			if (inet_bind_bucket_match(tb, net, port, l3mdev)) {
1058				if (tb->fastreuse >= 0 ||
1059				    tb->fastreuseport >= 0)
1060					goto next_port;
1061				WARN_ON(hlist_empty(&tb->bhash2));
1062				if (!check_established(death_row, sk,
1063						       port, &tw))
1064					goto ok;
1065				goto next_port;
1066			}
1067		}
1068
1069		tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
1070					     net, head, port, l3mdev);
1071		if (!tb) {
1072			spin_unlock_bh(&head->lock);
1073			return -ENOMEM;
 
 
 
 
 
 
1074		}
1075		tb_created = true;
1076		tb->fastreuse = -1;
1077		tb->fastreuseport = -1;
1078		goto ok;
1079next_port:
1080		spin_unlock_bh(&head->lock);
1081		cond_resched();
1082	}
1083
1084	if (!local_ports) {
1085		offset++;
1086		if ((offset & 1) && remaining > 1)
1087			goto other_parity_scan;
1088	}
1089	return -EADDRNOTAVAIL;
1090
1091ok:
1092	/* Find the corresponding tb2 bucket since we need to
1093	 * add the socket to the bhash2 table as well
1094	 */
1095	head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
1096	spin_lock(&head2->lock);
1097
1098	tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
1099	if (!tb2) {
1100		tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep, net,
1101					       head2, tb, sk);
1102		if (!tb2)
1103			goto error;
1104	}
1105
1106	/* Here we want to add a little bit of randomness to the next source
1107	 * port that will be chosen. We use a max() with a random here so that
1108	 * on low contention the randomness is maximal and on high contention
1109	 * it may be inexistent.
1110	 */
1111	i = max_t(int, i, get_random_u32_below(8) * step);
1112	WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + step);
1113
1114	/* Head lock still held and bh's disabled */
1115	inet_bind_hash(sk, tb, tb2, port);
 
 
 
 
 
1116
1117	if (sk_unhashed(sk)) {
1118		inet_sk(sk)->inet_sport = htons(port);
1119		inet_ehash_nolisten(sk, (struct sock *)tw, NULL);
1120	}
1121	if (tw)
1122		inet_twsk_bind_unhash(tw, hinfo);
1123
1124	spin_unlock(&head2->lock);
1125	spin_unlock(&head->lock);
1126
1127	if (tw)
1128		inet_twsk_deschedule_put(tw);
1129	local_bh_enable();
1130	return 0;
1131
1132error:
1133	if (sk_hashed(sk)) {
1134		spinlock_t *lock = inet_ehash_lockp(hinfo, sk->sk_hash);
1135
1136		sock_prot_inuse_add(net, sk->sk_prot, -1);
1137
1138		spin_lock(lock);
1139		__sk_nulls_del_node_init_rcu(sk);
1140		spin_unlock(lock);
1141
1142		sk->sk_hash = 0;
1143		inet_sk(sk)->inet_sport = 0;
1144		inet_sk(sk)->inet_num = 0;
1145
1146		if (tw)
1147			inet_twsk_bind_unhash(tw, hinfo);
1148	}
1149
1150	spin_unlock(&head2->lock);
1151	if (tb_created)
1152		inet_bind_bucket_destroy(hinfo->bind_bucket_cachep, tb);
1153	spin_unlock(&head->lock);
1154
1155	if (tw)
1156		inet_twsk_deschedule_put(tw);
1157
1158	local_bh_enable();
1159
1160	return -ENOMEM;
1161}
1162
1163/*
1164 * Bind a port for a connect operation and hash it.
1165 */
1166int inet_hash_connect(struct inet_timewait_death_row *death_row,
1167		      struct sock *sk)
1168{
1169	u64 port_offset = 0;
1170
1171	if (!inet_sk(sk)->inet_num)
1172		port_offset = inet_sk_port_offset(sk);
1173	return __inet_hash_connect(death_row, sk, port_offset,
1174				   __inet_check_established);
1175}
1176EXPORT_SYMBOL_GPL(inet_hash_connect);
1177
1178static void init_hashinfo_lhash2(struct inet_hashinfo *h)
1179{
1180	int i;
1181
1182	for (i = 0; i <= h->lhash2_mask; i++) {
1183		spin_lock_init(&h->lhash2[i].lock);
1184		INIT_HLIST_NULLS_HEAD(&h->lhash2[i].nulls_head,
 
1185				      i + LISTENING_NULLS_BASE);
1186	}
1187}
1188
1189void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
1190				unsigned long numentries, int scale,
1191				unsigned long low_limit,
1192				unsigned long high_limit)
1193{
1194	h->lhash2 = alloc_large_system_hash(name,
1195					    sizeof(*h->lhash2),
1196					    numentries,
1197					    scale,
1198					    0,
1199					    NULL,
1200					    &h->lhash2_mask,
1201					    low_limit,
1202					    high_limit);
1203	init_hashinfo_lhash2(h);
1204
1205	/* this one is used for source ports of outgoing connections */
1206	table_perturb = alloc_large_system_hash("Table-perturb",
1207						sizeof(*table_perturb),
1208						INET_TABLE_PERTURB_SIZE,
1209						0, 0, NULL, NULL,
1210						INET_TABLE_PERTURB_SIZE,
1211						INET_TABLE_PERTURB_SIZE);
1212}
1213
1214int inet_hashinfo2_init_mod(struct inet_hashinfo *h)
1215{
1216	h->lhash2 = kmalloc_array(INET_LHTABLE_SIZE, sizeof(*h->lhash2), GFP_KERNEL);
1217	if (!h->lhash2)
1218		return -ENOMEM;
1219
1220	h->lhash2_mask = INET_LHTABLE_SIZE - 1;
1221	/* INET_LHTABLE_SIZE must be a power of 2 */
1222	BUG_ON(INET_LHTABLE_SIZE & h->lhash2_mask);
1223
1224	init_hashinfo_lhash2(h);
1225	return 0;
1226}
1227EXPORT_SYMBOL_GPL(inet_hashinfo2_init_mod);
1228
1229int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
1230{
1231	unsigned int locksz = sizeof(spinlock_t);
1232	unsigned int i, nblocks = 1;
1233
1234	if (locksz != 0) {
1235		/* allocate 2 cache lines or at least one spinlock per cpu */
1236		nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
1237		nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
1238
1239		/* no more locks than number of hash buckets */
1240		nblocks = min(nblocks, hashinfo->ehash_mask + 1);
1241
1242		hashinfo->ehash_locks = kvmalloc_array(nblocks, locksz, GFP_KERNEL);
1243		if (!hashinfo->ehash_locks)
1244			return -ENOMEM;
1245
1246		for (i = 0; i < nblocks; i++)
1247			spin_lock_init(&hashinfo->ehash_locks[i]);
1248	}
1249	hashinfo->ehash_locks_mask = nblocks - 1;
1250	return 0;
1251}
1252EXPORT_SYMBOL_GPL(inet_ehash_locks_alloc);
1253
1254struct inet_hashinfo *inet_pernet_hashinfo_alloc(struct inet_hashinfo *hashinfo,
1255						 unsigned int ehash_entries)
1256{
1257	struct inet_hashinfo *new_hashinfo;
1258	int i;
1259
1260	new_hashinfo = kmemdup(hashinfo, sizeof(*hashinfo), GFP_KERNEL);
1261	if (!new_hashinfo)
1262		goto err;
1263
1264	new_hashinfo->ehash = vmalloc_huge(ehash_entries * sizeof(struct inet_ehash_bucket),
1265					   GFP_KERNEL_ACCOUNT);
1266	if (!new_hashinfo->ehash)
1267		goto free_hashinfo;
1268
1269	new_hashinfo->ehash_mask = ehash_entries - 1;
1270
1271	if (inet_ehash_locks_alloc(new_hashinfo))
1272		goto free_ehash;
1273
1274	for (i = 0; i < ehash_entries; i++)
1275		INIT_HLIST_NULLS_HEAD(&new_hashinfo->ehash[i].chain, i);
1276
1277	new_hashinfo->pernet = true;
1278
1279	return new_hashinfo;
1280
1281free_ehash:
1282	vfree(new_hashinfo->ehash);
1283free_hashinfo:
1284	kfree(new_hashinfo);
1285err:
1286	return NULL;
1287}
1288EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_alloc);
1289
1290void inet_pernet_hashinfo_free(struct inet_hashinfo *hashinfo)
1291{
1292	if (!hashinfo->pernet)
1293		return;
1294
1295	inet_ehash_locks_free(hashinfo);
1296	vfree(hashinfo->ehash);
1297	kfree(hashinfo);
1298}
1299EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_free);