[people/ms/linux.git] / net / rxrpc / local_object.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* Local endpoint object management
 *
 * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/udp.h>
#include <linux/ip.h>
#include <linux/hashtable.h>
#include <net/sock.h>
#include <net/udp.h>
#include <net/udp_tunnel.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"

static void rxrpc_local_processor(struct work_struct *);
static void rxrpc_local_rcu(struct rcu_head *);

/*
 * Compare a local to an address.  Return -ve, 0 or +ve to indicate less than,
 * same or greater than.
 *
 * We explicitly don't compare the RxRPC service ID as we want to reject
 * conflicting uses by differing services.  Further, we don't want to share
 * addresses with different options (IPv6), so we don't compare those bits
 * either.
 */
static long rxrpc_local_cmp_key(const struct rxrpc_local *local,
				const struct sockaddr_rxrpc *srx)
{
	long diff;

	diff = ((local->srx.transport_type - srx->transport_type) ?:
		(local->srx.transport_len - srx->transport_len) ?:
		(local->srx.transport.family - srx->transport.family));
	if (diff != 0)
		return diff;

	switch (srx->transport.family) {
	case AF_INET:
		/* If the choice of UDP port is left up to the transport, then
		 * the endpoint record doesn't match.
		 */
		return ((u16 __force)local->srx.transport.sin.sin_port -
			(u16 __force)srx->transport.sin.sin_port) ?:
			memcmp(&local->srx.transport.sin.sin_addr,
			       &srx->transport.sin.sin_addr,
			       sizeof(struct in_addr));
#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		/* If the choice of UDP6 port is left up to the transport, then
		 * the endpoint record doesn't match.
		 */
		return ((u16 __force)local->srx.transport.sin6.sin6_port -
			(u16 __force)srx->transport.sin6.sin6_port) ?:
			memcmp(&local->srx.transport.sin6.sin6_addr,
			       &srx->transport.sin6.sin6_addr,
			       sizeof(struct in6_addr));
#endif
	default:
		BUG();
	}
}

/*
 * Allocate a new local endpoint.
 */
static struct rxrpc_local *rxrpc_alloc_local(struct rxrpc_net *rxnet,
					     const struct sockaddr_rxrpc *srx)
{
	struct rxrpc_local *local;

	local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
	if (local) {
		refcount_set(&local->ref, 1);
		atomic_set(&local->active_users, 1);
		local->rxnet = rxnet;
		INIT_HLIST_NODE(&local->link);
		INIT_WORK(&local->processor, rxrpc_local_processor);
		init_rwsem(&local->defrag_sem);
		skb_queue_head_init(&local->reject_queue);
		skb_queue_head_init(&local->event_queue);
		local->client_bundles = RB_ROOT;
		spin_lock_init(&local->client_bundles_lock);
		spin_lock_init(&local->lock);
		rwlock_init(&local->services_lock);
		local->debug_id = atomic_inc_return(&rxrpc_debug_id);
		memcpy(&local->srx, srx, sizeof(*srx));
		local->srx.srx_service = 0;
		trace_rxrpc_local(local->debug_id, rxrpc_local_new, 1, NULL);
	}

	_leave(" = %p", local);
	return local;
}

/*
 * create the local socket
 * - must be called with rxrpc_local_mutex locked
 */
static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
{
	struct udp_tunnel_sock_cfg tuncfg = {NULL};
	struct sockaddr_rxrpc *srx = &local->srx;
	struct udp_port_cfg udp_conf = {0};
	struct sock *usk;
	int ret;

	_enter("%p{%d,%d}",
	       local, srx->transport_type, srx->transport.family);

	udp_conf.family = srx->transport.family;
	udp_conf.use_udp_checksums = true;
	if (udp_conf.family == AF_INET) {
		udp_conf.local_ip = srx->transport.sin.sin_addr;
		udp_conf.local_udp_port = srx->transport.sin.sin_port;
#if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
	} else {
		udp_conf.local_ip6 = srx->transport.sin6.sin6_addr;
		udp_conf.local_udp_port = srx->transport.sin6.sin6_port;
		udp_conf.use_udp6_tx_checksums = true;
		udp_conf.use_udp6_rx_checksums = true;
#endif
	}
	ret = udp_sock_create(net, &udp_conf, &local->socket);
	if (ret < 0) {
		_leave(" = %d [socket]", ret);
		return ret;
	}

	tuncfg.encap_type = UDP_ENCAP_RXRPC;
	tuncfg.encap_rcv = rxrpc_input_packet;
	tuncfg.sk_user_data = local;
	setup_udp_tunnel_sock(net, local->socket, &tuncfg);

	/* set the socket up */
	usk = local->socket->sk;
	usk->sk_error_report = rxrpc_error_report;

	switch (srx->transport.family) {
	case AF_INET6:
		/* we want to receive ICMPv6 errors */
		ip6_sock_set_recverr(usk);

		/* Fall through and set IPv4 options too otherwise we don't get
		 * errors from IPv4 packets sent through the IPv6 socket.
		 */
		fallthrough;
	case AF_INET:
		/* we want to receive ICMP errors */
		ip_sock_set_recverr(usk);

		/* we want to set the don't fragment bit */
		ip_sock_set_mtu_discover(usk, IP_PMTUDISC_DO);

		/* We want receive timestamps. */
		sock_enable_timestamps(usk);
		break;

	default:
		BUG();
	}

	_leave(" = 0");
	return 0;
}

/*
 * Look up or create a new local endpoint using the specified local address.
 */
struct rxrpc_local *rxrpc_lookup_local(struct net *net,
				       const struct sockaddr_rxrpc *srx)
{
	struct rxrpc_local *local;
	struct rxrpc_net *rxnet = rxrpc_net(net);
	struct hlist_node *cursor;
	const char *age;
	long diff;
	int ret;

	_enter("{%d,%d,%pISp}",
	       srx->transport_type, srx->transport.family, &srx->transport);

	mutex_lock(&rxnet->local_mutex);

	hlist_for_each(cursor, &rxnet->local_endpoints) {
		local = hlist_entry(cursor, struct rxrpc_local, link);

		diff = rxrpc_local_cmp_key(local, srx);
		if (diff != 0)
			continue;

		/* Services aren't allowed to share transport sockets, so
		 * reject that here.  It is possible that the object is dying -
		 * but it may also still have the local transport address that
		 * we want bound.
		 */
		if (srx->srx_service) {
			local = NULL;
			goto addr_in_use;
		}

		/* Found a match.  We want to replace a dying object.
		 * Attempting to bind the transport socket may still fail if
		 * we're attempting to use a local address that the dying
		 * object is still using.
		 */
		if (!rxrpc_use_local(local))
			break;

		age = "old";
		goto found;
	}

	local = rxrpc_alloc_local(rxnet, srx);
	if (!local)
		goto nomem;

	ret = rxrpc_open_socket(local, net);
	if (ret < 0)
		goto sock_error;

	if (cursor) {
		hlist_replace_rcu(cursor, &local->link);
		cursor->pprev = NULL;
	} else {
		hlist_add_head_rcu(&local->link, &rxnet->local_endpoints);
	}
	age = "new";

found:
	mutex_unlock(&rxnet->local_mutex);

	_net("LOCAL %s %d {%pISp}",
	     age, local->debug_id, &local->srx.transport);

	_leave(" = %p", local);
	return local;

nomem:
	ret = -ENOMEM;
sock_error:
	mutex_unlock(&rxnet->local_mutex);
	if (local)
		call_rcu(&local->rcu, rxrpc_local_rcu);
	_leave(" = %d", ret);
	return ERR_PTR(ret);

addr_in_use:
	mutex_unlock(&rxnet->local_mutex);
	_leave(" = -EADDRINUSE");
	return ERR_PTR(-EADDRINUSE);
}

/*
 * Get a ref on a local endpoint.
 */
struct rxrpc_local *rxrpc_get_local(struct rxrpc_local *local)
{
	const void *here = __builtin_return_address(0);
	int r;

	__refcount_inc(&local->ref, &r);
	trace_rxrpc_local(local->debug_id, rxrpc_local_got, r + 1, here);
	return local;
}

/*
 * Get a ref on a local endpoint unless its usage has already reached 0.
 */
struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local)
{
	const void *here = __builtin_return_address(0);
	int r;

	if (local) {
		if (__refcount_inc_not_zero(&local->ref, &r))
			trace_rxrpc_local(local->debug_id, rxrpc_local_got,
					  r + 1, here);
		else
			local = NULL;
	}
	return local;
}

/*
 * Queue a local endpoint and pass the caller's reference to the work item.
 */
void rxrpc_queue_local(struct rxrpc_local *local)
{
	const void *here = __builtin_return_address(0);
	unsigned int debug_id = local->debug_id;
	int r = refcount_read(&local->ref);

	if (rxrpc_queue_work(&local->processor))
		trace_rxrpc_local(debug_id, rxrpc_local_queued, r + 1, here);
	else
		rxrpc_put_local(local);
}

/*
 * Drop a ref on a local endpoint.
 */
void rxrpc_put_local(struct rxrpc_local *local)
{
	const void *here = __builtin_return_address(0);
	unsigned int debug_id;
	bool dead;
	int r;

	if (local) {
		debug_id = local->debug_id;

		dead = __refcount_dec_and_test(&local->ref, &r);
		trace_rxrpc_local(debug_id, rxrpc_local_put, r, here);

		if (dead)
			call_rcu(&local->rcu, rxrpc_local_rcu);
	}
}

/*
 * Start using a local endpoint.
 */
struct rxrpc_local *rxrpc_use_local(struct rxrpc_local *local)
{
	local = rxrpc_get_local_maybe(local);
	if (!local)
		return NULL;

	if (!__rxrpc_use_local(local)) {
		rxrpc_put_local(local);
		return NULL;
	}

	return local;
}

/*
 * Cease using a local endpoint.  Once the number of active users reaches 0, we
 * start the closure of the transport in the work processor.
 */
void rxrpc_unuse_local(struct rxrpc_local *local)
{
	if (local) {
		if (__rxrpc_unuse_local(local)) {
			rxrpc_get_local(local);
			rxrpc_queue_local(local);
		}
	}
}

/*
 * Destroy a local endpoint's socket and then hand the record to RCU to dispose
 * of.
 *
 * Closing the socket cannot be done from bottom half context or RCU callback
 * context because it might sleep.
 */
static void rxrpc_local_destroyer(struct rxrpc_local *local)
{
	struct socket *socket = local->socket;
	struct rxrpc_net *rxnet = local->rxnet;

	_enter("%d", local->debug_id);

	local->dead = true;

	mutex_lock(&rxnet->local_mutex);
	hlist_del_init_rcu(&local->link);
	mutex_unlock(&rxnet->local_mutex);

	rxrpc_clean_up_local_conns(local);
	rxrpc_service_connection_reaper(&rxnet->service_conn_reaper);
	ASSERT(!local->service);

	if (socket) {
		local->socket = NULL;
		kernel_sock_shutdown(socket, SHUT_RDWR);
		socket->sk->sk_user_data = NULL;
		sock_release(socket);
	}

	/* At this point, there should be no more packets coming in to the
	 * local endpoint.
	 */
	rxrpc_purge_queue(&local->reject_queue);
	rxrpc_purge_queue(&local->event_queue);
}

/*
 * Process events on an endpoint.  The work item carries a ref which
 * we must release.
 */
static void rxrpc_local_processor(struct work_struct *work)
{
	struct rxrpc_local *local =
		container_of(work, struct rxrpc_local, processor);
	bool again;

	trace_rxrpc_local(local->debug_id, rxrpc_local_processing,
			  refcount_read(&local->ref), NULL);

	do {
		again = false;
		if (!__rxrpc_use_local(local)) {
			rxrpc_local_destroyer(local);
			break;
		}

		if (!skb_queue_empty(&local->reject_queue)) {
			rxrpc_reject_packets(local);
			again = true;
		}

		if (!skb_queue_empty(&local->event_queue)) {
			rxrpc_process_local_events(local);
			again = true;
		}

		__rxrpc_unuse_local(local);
	} while (again);

	rxrpc_put_local(local);
}

/*
 * Destroy a local endpoint after the RCU grace period expires.
 */
static void rxrpc_local_rcu(struct rcu_head *rcu)
{
	struct rxrpc_local *local = container_of(rcu, struct rxrpc_local, rcu);

	_enter("%d", local->debug_id);

	ASSERT(!work_pending(&local->processor));

	_net("DESTROY LOCAL %d", local->debug_id);
	kfree(local);
	_leave("");
}

/*
 * Verify the local endpoint list is empty by this point.
 */
void rxrpc_destroy_all_locals(struct rxrpc_net *rxnet)
{
	struct rxrpc_local *local;

	_enter("");

	flush_workqueue(rxrpc_workqueue);

	if (!hlist_empty(&rxnet->local_endpoints)) {
		mutex_lock(&rxnet->local_mutex);
		hlist_for_each_entry(local, &rxnet->local_endpoints, link) {
			pr_err("AF_RXRPC: Leaked local %p {%d}\n",
			       local, refcount_read(&local->ref));
		}
		mutex_unlock(&rxnet->local_mutex);
		BUG();
	}
}
Commit	Line	Data
b4d0d230	1	// SPDX-License-Identifier: GPL-2.0-or-later
87563616	2	/* Local endpoint object management
17926a79	3	*
4f95dd78	4	* Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
17926a79	5	* Written by David Howells (dhowells@redhat.com)
17926a79 DH	6	*/
17926a79 DH	7
9b6d5398 JP	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9b6d5398 JP	9
17926a79 DH	10	#include <linux/module.h>
	11	#include <linux/net.h>
	12	#include <linux/skbuff.h>
5a0e3ad6	13	#include <linux/slab.h>
44ba0698 DH	14	#include <linux/udp.h>
44ba0698 DH	15	#include <linux/ip.h>
4f95dd78	16	#include <linux/hashtable.h>
17926a79	17	#include <net/sock.h>
5271953c	18	#include <net/udp.h>
5d30c626	19	#include <net/udp_tunnel.h>
17926a79 DH	20	#include <net/af_rxrpc.h>
	21	#include "ar-internal.h"
	22
4f95dd78 DH	23	static void rxrpc_local_processor(struct work_struct *);
4f95dd78 DH	24	static void rxrpc_local_rcu(struct rcu_head *);
17926a79	25
17926a79	26	/*
4f95dd78 DH	27	* Compare a local to an address. Return -ve, 0 or +ve to indicate less than,
	28	* same or greater than.
	29	*
	30	* We explicitly don't compare the RxRPC service ID as we want to reject
	31	* conflicting uses by differing services. Further, we don't want to share
	32	* addresses with different options (IPv6), so we don't compare those bits
	33	* either.
17926a79	34	*/
4f95dd78 DH	35	static long rxrpc_local_cmp_key(const struct rxrpc_local *local,
	36	const struct sockaddr_rxrpc *srx)
	37	{
	38	long diff;
	39
	40	diff = ((local->srx.transport_type - srx->transport_type) ?:
	41	(local->srx.transport_len - srx->transport_len) ?:
	42	(local->srx.transport.family - srx->transport.family));
	43	if (diff != 0)
	44	return diff;
	45
	46	switch (srx->transport.family) {
	47	case AF_INET:
	48	/* If the choice of UDP port is left up to the transport, then
	49	* the endpoint record doesn't match.
	50	*/
	51	return ((u16 __force)local->srx.transport.sin.sin_port -
	52	(u16 __force)srx->transport.sin.sin_port) ?:
	53	memcmp(&local->srx.transport.sin.sin_addr,
	54	&srx->transport.sin.sin_addr,
	55	sizeof(struct in_addr));
d1912747	56	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	57	case AF_INET6:
	58	/* If the choice of UDP6 port is left up to the transport, then
	59	* the endpoint record doesn't match.
	60	*/
	61	return ((u16 __force)local->srx.transport.sin6.sin6_port -
	62	(u16 __force)srx->transport.sin6.sin6_port) ?:
	63	memcmp(&local->srx.transport.sin6.sin6_addr,
	64	&srx->transport.sin6.sin6_addr,
	65	sizeof(struct in6_addr));
d1912747	66	#endif
4f95dd78 DH	67	default:
	68	BUG();
	69	}
	70	}
	71
	72	/*
	73	* Allocate a new local endpoint.
	74	*/
2baec2c3 DH	75	static struct rxrpc_local rxrpc_alloc_local(struct rxrpc_net rxnet,
2baec2c3 DH	76	const struct sockaddr_rxrpc *srx)
17926a79 DH	77	{
	78	struct rxrpc_local *local;
	79
	80	local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
	81	if (local) {
a0575429	82	refcount_set(&local->ref, 1);
730c5fd4	83	atomic_set(&local->active_users, 1);
2baec2c3	84	local->rxnet = rxnet;
33912c26	85	INIT_HLIST_NODE(&local->link);
4f95dd78	86	INIT_WORK(&local->processor, rxrpc_local_processor);
17926a79	87	init_rwsem(&local->defrag_sem);
17926a79	88	skb_queue_head_init(&local->reject_queue);
44ba0698	89	skb_queue_head_init(&local->event_queue);
245500d8 DH	90	local->client_bundles = RB_ROOT;
245500d8 DH	91	spin_lock_init(&local->client_bundles_lock);
17926a79 DH	92	spin_lock_init(&local->lock);
17926a79 DH	93	rwlock_init(&local->services_lock);
17926a79 DH	94	local->debug_id = atomic_inc_return(&rxrpc_debug_id);
17926a79 DH	95	memcpy(&local->srx, srx, sizeof(*srx));
28036f44	96	local->srx.srx_service = 0;
06d9532f	97	trace_rxrpc_local(local->debug_id, rxrpc_local_new, 1, NULL);
17926a79 DH	98	}
	99
	100	_leave(" = %p", local);
	101	return local;
	102	}
	103
	104	/*
	105	* create the local socket
4f95dd78	106	* - must be called with rxrpc_local_mutex locked
17926a79	107	*/
2baec2c3	108	static int rxrpc_open_socket(struct rxrpc_local local, struct net net)
17926a79	109	{
1a9b86c9 XL	110	struct udp_tunnel_sock_cfg tuncfg = {NULL};
	111	struct sockaddr_rxrpc *srx = &local->srx;
	112	struct udp_port_cfg udp_conf = {0};
5271953c	113	struct sock *usk;
fce93494	114	int ret;
17926a79	115
75b54cb5	116	_enter("%p{%d,%d}",
1a9b86c9 XL	117	local, srx->transport_type, srx->transport.family);
	118
	119	udp_conf.family = srx->transport.family;
39cb9faa	120	udp_conf.use_udp_checksums = true;
1a9b86c9 XL	121	if (udp_conf.family == AF_INET) {
	122	udp_conf.local_ip = srx->transport.sin.sin_addr;
	123	udp_conf.local_udp_port = srx->transport.sin.sin_port;
295f830e	124	#if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
1a9b86c9 XL	125	} else {
	126	udp_conf.local_ip6 = srx->transport.sin6.sin6_addr;
	127	udp_conf.local_udp_port = srx->transport.sin6.sin6_port;
39cb9faa DH	128	udp_conf.use_udp6_tx_checksums = true;
39cb9faa DH	129	udp_conf.use_udp6_rx_checksums = true;
295f830e	130	#endif
1a9b86c9 XL	131	}
1a9b86c9 XL	132	ret = udp_sock_create(net, &udp_conf, &local->socket);
17926a79 DH	133	if (ret < 0) {
	134	_leave(" = %d [socket]", ret);
	135	return ret;
	136	}
	137
1a9b86c9 XL	138	tuncfg.encap_type = UDP_ENCAP_RXRPC;
	139	tuncfg.encap_rcv = rxrpc_input_packet;
	140	tuncfg.sk_user_data = local;
	141	setup_udp_tunnel_sock(net, local->socket, &tuncfg);
	142
2cfa2271	143	/* set the socket up */
5271953c	144	usk = local->socket->sk;
5271953c	145	usk->sk_error_report = rxrpc_error_report;
2cfa2271	146
1a9b86c9	147	switch (srx->transport.family) {
37a675e7 DH	148	case AF_INET6:
37a675e7 DH	149	/* we want to receive ICMPv6 errors */
1a9b86c9	150	ip6_sock_set_recverr(usk);
17926a79	151
37a675e7 DH	152	/* Fall through and set IPv4 options too otherwise we don't get
	153	* errors from IPv4 packets sent through the IPv6 socket.
	154	*/
df561f66	155	fallthrough;
37a675e7	156	case AF_INET:
f2aeed3a	157	/* we want to receive ICMP errors */
1a9b86c9	158	ip_sock_set_recverr(usk);
f2aeed3a DH	159
f2aeed3a DH	160	/* we want to set the don't fragment bit */
1a9b86c9	161	ip_sock_set_mtu_discover(usk, IP_PMTUDISC_DO);
b604dd98 DH	162
b604dd98 DH	163	/* We want receive timestamps. */
1a9b86c9	164	sock_enable_timestamps(usk);
f2aeed3a DH	165	break;
	166
	167	default:
	168	BUG();
17926a79 DH	169	}
17926a79 DH	170
17926a79 DH	171	_leave(" = 0");
17926a79 DH	172	return 0;
17926a79 DH	173	}
	174
	175	/*
4f95dd78	176	* Look up or create a new local endpoint using the specified local address.
17926a79	177	*/
2baec2c3 DH	178	struct rxrpc_local rxrpc_lookup_local(struct net net,
2baec2c3 DH	179	const struct sockaddr_rxrpc *srx)
17926a79 DH	180	{
17926a79 DH	181	struct rxrpc_local *local;
2baec2c3	182	struct rxrpc_net *rxnet = rxrpc_net(net);
33912c26	183	struct hlist_node *cursor;
4f95dd78 DH	184	const char *age;
4f95dd78 DH	185	long diff;
17926a79 DH	186	int ret;
17926a79 DH	187
75b54cb5 DH	188	_enter("{%d,%d,%pISp}",
75b54cb5 DH	189	srx->transport_type, srx->transport.family, &srx->transport);
17926a79	190
2baec2c3	191	mutex_lock(&rxnet->local_mutex);
17926a79	192
33912c26 DH	193	hlist_for_each(cursor, &rxnet->local_endpoints) {
33912c26 DH	194	local = hlist_entry(cursor, struct rxrpc_local, link);
17926a79	195
4f95dd78	196	diff = rxrpc_local_cmp_key(local, srx);
33912c26	197	if (diff != 0)
17926a79	198	continue;
4f95dd78 DH	199
	200	/* Services aren't allowed to share transport sockets, so
	201	* reject that here. It is possible that the object is dying -
	202	* but it may also still have the local transport address that
	203	* we want bound.
	204	*/
	205	if (srx->srx_service) {
	206	local = NULL;
	207	goto addr_in_use;
	208	}
17926a79	209
33912c26 DH	210	/* Found a match. We want to replace a dying object.
	211	* Attempting to bind the transport socket may still fail if
	212	* we're attempting to use a local address that the dying
	213	* object is still using.
4f95dd78	214	*/
730c5fd4	215	if (!rxrpc_use_local(local))
4f95dd78	216	break;
17926a79	217
4f95dd78 DH	218	age = "old";
	219	goto found;
	220	}
17926a79	221
2baec2c3	222	local = rxrpc_alloc_local(rxnet, srx);
4f95dd78 DH	223	if (!local)
4f95dd78 DH	224	goto nomem;
17926a79	225
2baec2c3	226	ret = rxrpc_open_socket(local, net);
4f95dd78 DH	227	if (ret < 0)
	228	goto sock_error;
	229
33912c26 DH	230	if (cursor) {
	231	hlist_replace_rcu(cursor, &local->link);
	232	cursor->pprev = NULL;
	233	} else {
	234	hlist_add_head_rcu(&local->link, &rxnet->local_endpoints);
	235	}
4f95dd78	236	age = "new";
17926a79	237
4f95dd78	238	found:
2baec2c3	239	mutex_unlock(&rxnet->local_mutex);
17926a79	240
75b54cb5 DH	241	_net("LOCAL %s %d {%pISp}",
75b54cb5 DH	242	age, local->debug_id, &local->srx.transport);
17926a79	243
4f95dd78	244	_leave(" = %p", local);
17926a79 DH	245	return local;
17926a79 DH	246
4f95dd78 DH	247	nomem:
	248	ret = -ENOMEM;
	249	sock_error:
2baec2c3	250	mutex_unlock(&rxnet->local_mutex);
032be5f1 ED	251	if (local)
032be5f1 ED	252	call_rcu(&local->rcu, rxrpc_local_rcu);
4f95dd78 DH	253	_leave(" = %d", ret);
4f95dd78 DH	254	return ERR_PTR(ret);
17926a79	255
4f95dd78	256	addr_in_use:
2baec2c3	257	mutex_unlock(&rxnet->local_mutex);
4f95dd78 DH	258	_leave(" = -EADDRINUSE");
	259	return ERR_PTR(-EADDRINUSE);
	260	}
17926a79	261
09d2bf59 DH	262	/*
	263	* Get a ref on a local endpoint.
	264	*/
	265	struct rxrpc_local rxrpc_get_local(struct rxrpc_local local)
	266	{
	267	const void *here = __builtin_return_address(0);
a0575429	268	int r;
09d2bf59	269
a0575429 DH	270	__refcount_inc(&local->ref, &r);
a0575429 DH	271	trace_rxrpc_local(local->debug_id, rxrpc_local_got, r + 1, here);
09d2bf59 DH	272	return local;
	273	}
	274
	275	/*
	276	* Get a ref on a local endpoint unless its usage has already reached 0.
	277	*/
	278	struct rxrpc_local rxrpc_get_local_maybe(struct rxrpc_local local)
	279	{
	280	const void *here = __builtin_return_address(0);
a0575429	281	int r;
09d2bf59 DH	282
09d2bf59 DH	283	if (local) {
a0575429	284	if (__refcount_inc_not_zero(&local->ref, &r))
06d9532f	285	trace_rxrpc_local(local->debug_id, rxrpc_local_got,
a0575429	286	r + 1, here);
09d2bf59 DH	287	else
	288	local = NULL;
	289	}
	290	return local;
	291	}
	292
	293	/*
06d9532f	294	* Queue a local endpoint and pass the caller's reference to the work item.
09d2bf59 DH	295	*/
	296	void rxrpc_queue_local(struct rxrpc_local *local)
	297	{
	298	const void *here = __builtin_return_address(0);
06d9532f	299	unsigned int debug_id = local->debug_id;
a0575429	300	int r = refcount_read(&local->ref);
09d2bf59 DH	301
09d2bf59 DH	302	if (rxrpc_queue_work(&local->processor))
a0575429	303	trace_rxrpc_local(debug_id, rxrpc_local_queued, r + 1, here);
730c5fd4 DH	304	else
730c5fd4 DH	305	rxrpc_put_local(local);
17926a79 DH	306	}
17926a79 DH	307
09d2bf59 DH	308	/*
	309	* Drop a ref on a local endpoint.
	310	*/
	311	void rxrpc_put_local(struct rxrpc_local *local)
	312	{
	313	const void *here = __builtin_return_address(0);
fac20b9e	314	unsigned int debug_id;
a0575429 DH	315	bool dead;
a0575429 DH	316	int r;
09d2bf59 DH	317
09d2bf59 DH	318	if (local) {
fac20b9e DH	319	debug_id = local->debug_id;
fac20b9e DH	320
a0575429 DH	321	dead = __refcount_dec_and_test(&local->ref, &r);
a0575429 DH	322	trace_rxrpc_local(debug_id, rxrpc_local_put, r, here);
09d2bf59	323
a0575429	324	if (dead)
730c5fd4	325	call_rcu(&local->rcu, rxrpc_local_rcu);
09d2bf59 DH	326	}
	327	}
	328
730c5fd4 DH	329	/*
	330	* Start using a local endpoint.
	331	*/
	332	struct rxrpc_local rxrpc_use_local(struct rxrpc_local local)
	333	{
730c5fd4 DH	334	local = rxrpc_get_local_maybe(local);
	335	if (!local)
	336	return NULL;
	337
04d36d74	338	if (!__rxrpc_use_local(local)) {
730c5fd4 DH	339	rxrpc_put_local(local);
	340	return NULL;
	341	}
	342
	343	return local;
	344	}
	345
	346	/*
	347	* Cease using a local endpoint. Once the number of active users reaches 0, we
	348	* start the closure of the transport in the work processor.
	349	*/
	350	void rxrpc_unuse_local(struct rxrpc_local *local)
	351	{
68553f1a	352	if (local) {
04d36d74 DH	353	if (__rxrpc_unuse_local(local)) {
04d36d74 DH	354	rxrpc_get_local(local);
68553f1a	355	rxrpc_queue_local(local);
04d36d74	356	}
68553f1a	357	}
730c5fd4 DH	358	}
730c5fd4 DH	359
17926a79	360	/*
4f95dd78 DH	361	* Destroy a local endpoint's socket and then hand the record to RCU to dispose
	362	* of.
	363	*
	364	* Closing the socket cannot be done from bottom half context or RCU callback
	365	* context because it might sleep.
17926a79	366	*/
4f95dd78	367	static void rxrpc_local_destroyer(struct rxrpc_local *local)
17926a79	368	{
4f95dd78	369	struct socket *socket = local->socket;
2baec2c3	370	struct rxrpc_net *rxnet = local->rxnet;
17926a79	371
4f95dd78	372	_enter("%d", local->debug_id);
17926a79	373
d12040b6 DH	374	local->dead = true;
d12040b6 DH	375
2baec2c3	376	mutex_lock(&rxnet->local_mutex);
33912c26	377	hlist_del_init_rcu(&local->link);
2baec2c3	378	mutex_unlock(&rxnet->local_mutex);
4f95dd78	379
d12040b6 DH	380	rxrpc_clean_up_local_conns(local);
d12040b6 DH	381	rxrpc_service_connection_reaper(&rxnet->service_conn_reaper);
1e9e5c95	382	ASSERT(!local->service);
4f95dd78 DH	383
	384	if (socket) {
	385	local->socket = NULL;
	386	kernel_sock_shutdown(socket, SHUT_RDWR);
	387	socket->sk->sk_user_data = NULL;
	388	sock_release(socket);
	389	}
	390
	391	/* At this point, there should be no more packets coming in to the
	392	* local endpoint.
	393	*/
4f95dd78 DH	394	rxrpc_purge_queue(&local->reject_queue);
4f95dd78 DH	395	rxrpc_purge_queue(&local->event_queue);
17926a79 DH	396	}
	397
	398	/*
730c5fd4 DH	399	* Process events on an endpoint. The work item carries a ref which
730c5fd4 DH	400	* we must release.
17926a79	401	*/
4f95dd78	402	static void rxrpc_local_processor(struct work_struct *work)
17926a79 DH	403	{
17926a79 DH	404	struct rxrpc_local *local =
4f95dd78 DH	405	container_of(work, struct rxrpc_local, processor);
4f95dd78 DH	406	bool again;
17926a79	407
06d9532f	408	trace_rxrpc_local(local->debug_id, rxrpc_local_processing,
a0575429	409	refcount_read(&local->ref), NULL);
17926a79	410
4f95dd78 DH	411	do {
4f95dd78 DH	412	again = false;
04d36d74	413	if (!__rxrpc_use_local(local)) {
730c5fd4 DH	414	rxrpc_local_destroyer(local);
	415	break;
	416	}
17926a79	417
4f95dd78 DH	418	if (!skb_queue_empty(&local->reject_queue)) {
	419	rxrpc_reject_packets(local);
	420	again = true;
	421	}
17926a79	422
4f95dd78 DH	423	if (!skb_queue_empty(&local->event_queue)) {
	424	rxrpc_process_local_events(local);
	425	again = true;
	426	}
04d36d74 DH	427
04d36d74 DH	428	__rxrpc_unuse_local(local);
4f95dd78	429	} while (again);
730c5fd4 DH	430
730c5fd4 DH	431	rxrpc_put_local(local);
4f95dd78	432	}
17926a79	433
4f95dd78 DH	434	/*
	435	* Destroy a local endpoint after the RCU grace period expires.
	436	*/
	437	static void rxrpc_local_rcu(struct rcu_head *rcu)
	438	{
	439	struct rxrpc_local *local = container_of(rcu, struct rxrpc_local, rcu);
17926a79	440
4f95dd78	441	_enter("%d", local->debug_id);
17926a79	442
4f95dd78	443	ASSERT(!work_pending(&local->processor));
17926a79 DH	444
	445	_net("DESTROY LOCAL %d", local->debug_id);
	446	kfree(local);
17926a79 DH	447	_leave("");
	448	}
	449
	450	/*
4f95dd78	451	* Verify the local endpoint list is empty by this point.
17926a79	452	*/
2baec2c3	453	void rxrpc_destroy_all_locals(struct rxrpc_net *rxnet)
17926a79	454	{
4f95dd78	455	struct rxrpc_local *local;
17926a79 DH	456
	457	_enter("");
	458
dee46364	459	flush_workqueue(rxrpc_workqueue);
17926a79	460
33912c26	461	if (!hlist_empty(&rxnet->local_endpoints)) {
2baec2c3	462	mutex_lock(&rxnet->local_mutex);
33912c26	463	hlist_for_each_entry(local, &rxnet->local_endpoints, link) {
dee46364	464	pr_err("AF_RXRPC: Leaked local %p {%d}\n",
a0575429	465	local, refcount_read(&local->ref));
dee46364	466	}
2baec2c3	467	mutex_unlock(&rxnet->local_mutex);
dee46364	468	BUG();
17926a79	469	}
17926a79	470	}