[linux-2.6-block.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_rcu(struct rcu_head *);

/*
 * Handle an ICMP/ICMP6 error turning up at the tunnel.  Push it through the
 * usual mechanism so that it gets parsed and presented through the UDP
 * socket's error_report().
 */
static void rxrpc_encap_err_rcv(struct sock *sk, struct sk_buff *skb, int err,
				__be16 port, u32 info, u8 *payload)
{
	if (ip_hdr(skb)->version == IPVERSION)
		return ip_icmp_error(sk, skb, err, port, info, payload);
	if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6))
		return ipv6_icmp_error(sk, skb, err, port, info, payload);
}

/*
 * 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();
	}
}

static void rxrpc_client_conn_reap_timeout(struct timer_list *timer)
{
	struct rxrpc_local *local =
		container_of(timer, struct rxrpc_local, client_conn_reap_timer);

	if (!local->kill_all_client_conns &&
	    test_and_set_bit(RXRPC_CLIENT_CONN_REAP_TIMER, &local->client_conn_flags))
		rxrpc_wake_up_io_thread(local);
}

/*
 * Allocate a new local endpoint.
 */
static struct rxrpc_local *rxrpc_alloc_local(struct net *net,
					     const struct sockaddr_rxrpc *srx)
{
	struct rxrpc_local *local;
	u32 tmp;

	local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
	if (local) {
		refcount_set(&local->ref, 1);
		atomic_set(&local->active_users, 1);
		local->net = net;
		local->rxnet = rxrpc_net(net);
		INIT_HLIST_NODE(&local->link);
		init_completion(&local->io_thread_ready);
#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
		skb_queue_head_init(&local->rx_delay_queue);
#endif
		skb_queue_head_init(&local->rx_queue);
		INIT_LIST_HEAD(&local->conn_attend_q);
		INIT_LIST_HEAD(&local->call_attend_q);

		local->client_bundles = RB_ROOT;
		spin_lock_init(&local->client_bundles_lock);
		local->kill_all_client_conns = false;
		INIT_LIST_HEAD(&local->idle_client_conns);
		timer_setup(&local->client_conn_reap_timer,
			    rxrpc_client_conn_reap_timeout, 0);

		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;
		idr_init(&local->conn_ids);
		get_random_bytes(&tmp, sizeof(tmp));
		tmp &= 0x3fffffff;
		if (tmp == 0)
			tmp = 1;
		idr_set_cursor(&local->conn_ids, tmp);
		INIT_LIST_HEAD(&local->new_client_calls);
		spin_lock_init(&local->client_call_lock);

		trace_rxrpc_local(local->debug_id, rxrpc_local_new, 1, 1);
	}

	_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 task_struct *io_thread;
	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_encap_rcv;
	tuncfg.encap_err_rcv = rxrpc_encap_err_rcv;
	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();
	}

	io_thread = kthread_run(rxrpc_io_thread, local,
				"krxrpcio/%u", ntohs(udp_conf.local_udp_port));
	if (IS_ERR(io_thread)) {
		ret = PTR_ERR(io_thread);
		goto error_sock;
	}

	wait_for_completion(&local->io_thread_ready);
	local->io_thread = io_thread;
	_leave(" = 0");
	return 0;

error_sock:
	kernel_sock_shutdown(local->socket, SHUT_RDWR);
	local->socket->sk->sk_user_data = NULL;
	sock_release(local->socket);
	local->socket = NULL;
	return ret;
}

/*
 * 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;
	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, rxrpc_local_use_lookup))
			break;

		goto found;
	}

	local = rxrpc_alloc_local(net, 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);
	}

found:
	mutex_unlock(&rxnet->local_mutex);
	_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,
				    enum rxrpc_local_trace why)
{
	int r, u;

	u = atomic_read(&local->active_users);
	__refcount_inc(&local->ref, &r);
	trace_rxrpc_local(local->debug_id, why, r + 1, u);
	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,
					  enum rxrpc_local_trace why)
{
	int r, u;

	if (local && __refcount_inc_not_zero(&local->ref, &r)) {
		u = atomic_read(&local->active_users);
		trace_rxrpc_local(local->debug_id, why, r + 1, u);
		return local;
	}

	return NULL;
}

/*
 * Drop a ref on a local endpoint.
 */
void rxrpc_put_local(struct rxrpc_local *local, enum rxrpc_local_trace why)
{
	unsigned int debug_id;
	bool dead;
	int r, u;

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

		u = atomic_read(&local->active_users);
		dead = __refcount_dec_and_test(&local->ref, &r);
		trace_rxrpc_local(debug_id, why, r, u);

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

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

	if (!__rxrpc_use_local(local, why)) {
		rxrpc_put_local(local, rxrpc_local_put_for_use);
		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 I/O thread..
 */
void rxrpc_unuse_local(struct rxrpc_local *local, enum rxrpc_local_trace why)
{
	unsigned int debug_id;
	int r, u;

	if (local) {
		debug_id = local->debug_id;
		r = refcount_read(&local->ref);
		u = atomic_dec_return(&local->active_users);
		trace_rxrpc_local(debug_id, why, r, u);
		if (u == 0)
			kthread_stop(local->io_thread);
	}
}

/*
 * 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.
 */
void rxrpc_destroy_local(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.
	 */
#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
	rxrpc_purge_queue(&local->rx_delay_queue);
#endif
	rxrpc_purge_queue(&local->rx_queue);
	rxrpc_purge_client_connections(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);

	rxrpc_see_local(local, rxrpc_local_free);
	kfree(local);
}

/*
 * 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	23	static void rxrpc_local_rcu(struct rcu_head *);
17926a79	24
b6c66c43 DH	25	/*
	26	* Handle an ICMP/ICMP6 error turning up at the tunnel. Push it through the
	27	* usual mechanism so that it gets parsed and presented through the UDP
	28	* socket's error_report().
	29	*/
	30	static void rxrpc_encap_err_rcv(struct sock sk, struct sk_buff skb, int err,
	31	__be16 port, u32 info, u8 *payload)
	32	{
	33	if (ip_hdr(skb)->version == IPVERSION)
	34	return ip_icmp_error(sk, skb, err, port, info, payload);
41cf3a91 DH	35	if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6))
41cf3a91 DH	36	return ipv6_icmp_error(sk, skb, err, port, info, payload);
b6c66c43 DH	37	}
b6c66c43 DH	38
17926a79	39	/*
4f95dd78 DH	40	* Compare a local to an address. Return -ve, 0 or +ve to indicate less than,
	41	* same or greater than.
	42	*
	43	* We explicitly don't compare the RxRPC service ID as we want to reject
	44	* conflicting uses by differing services. Further, we don't want to share
	45	* addresses with different options (IPv6), so we don't compare those bits
	46	* either.
17926a79	47	*/
4f95dd78 DH	48	static long rxrpc_local_cmp_key(const struct rxrpc_local *local,
	49	const struct sockaddr_rxrpc *srx)
	50	{
	51	long diff;
	52
	53	diff = ((local->srx.transport_type - srx->transport_type) ?:
	54	(local->srx.transport_len - srx->transport_len) ?:
	55	(local->srx.transport.family - srx->transport.family));
	56	if (diff != 0)
	57	return diff;
	58
	59	switch (srx->transport.family) {
	60	case AF_INET:
	61	/* If the choice of UDP port is left up to the transport, then
	62	* the endpoint record doesn't match.
	63	*/
	64	return ((u16 __force)local->srx.transport.sin.sin_port -
	65	(u16 __force)srx->transport.sin.sin_port) ?:
	66	memcmp(&local->srx.transport.sin.sin_addr,
	67	&srx->transport.sin.sin_addr,
	68	sizeof(struct in_addr));
d1912747	69	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	70	case AF_INET6:
	71	/* If the choice of UDP6 port is left up to the transport, then
	72	* the endpoint record doesn't match.
	73	*/
	74	return ((u16 __force)local->srx.transport.sin6.sin6_port -
	75	(u16 __force)srx->transport.sin6.sin6_port) ?:
	76	memcmp(&local->srx.transport.sin6.sin6_addr,
	77	&srx->transport.sin6.sin6_addr,
	78	sizeof(struct in6_addr));
d1912747	79	#endif
4f95dd78 DH	80	default:
	81	BUG();
	82	}
	83	}
	84
0d6bf319 DH	85	static void rxrpc_client_conn_reap_timeout(struct timer_list *timer)
	86	{
	87	struct rxrpc_local *local =
	88	container_of(timer, struct rxrpc_local, client_conn_reap_timer);
	89
61e4a866	90	if (!local->kill_all_client_conns &&
0d6bf319 DH	91	test_and_set_bit(RXRPC_CLIENT_CONN_REAP_TIMER, &local->client_conn_flags))
	92	rxrpc_wake_up_io_thread(local);
	93	}
	94
4f95dd78 DH	95	/*
	96	* Allocate a new local endpoint.
	97	*/
8a758d98	98	static struct rxrpc_local rxrpc_alloc_local(struct net net,
2baec2c3	99	const struct sockaddr_rxrpc *srx)
17926a79 DH	100	{
17926a79 DH	101	struct rxrpc_local *local;
f06cb291	102	u32 tmp;
17926a79 DH	103
	104	local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
	105	if (local) {
a0575429	106	refcount_set(&local->ref, 1);
730c5fd4	107	atomic_set(&local->active_users, 1);
8a758d98 DH	108	local->net = net;
8a758d98 DH	109	local->rxnet = rxrpc_net(net);
33912c26	110	INIT_HLIST_NODE(&local->link);
8fbcc833	111	init_completion(&local->io_thread_ready);
af094824 DH	112	#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
	113	skb_queue_head_init(&local->rx_delay_queue);
	114	#endif
a275da62	115	skb_queue_head_init(&local->rx_queue);
f2cce89a	116	INIT_LIST_HEAD(&local->conn_attend_q);
15f661dc	117	INIT_LIST_HEAD(&local->call_attend_q);
0d6bf319	118
245500d8 DH	119	local->client_bundles = RB_ROOT;
245500d8 DH	120	spin_lock_init(&local->client_bundles_lock);
0d6bf319	121	local->kill_all_client_conns = false;
0d6bf319 DH	122	INIT_LIST_HEAD(&local->idle_client_conns);
	123	timer_setup(&local->client_conn_reap_timer,
	124	rxrpc_client_conn_reap_timeout, 0);
	125
17926a79 DH	126	spin_lock_init(&local->lock);
17926a79 DH	127	rwlock_init(&local->services_lock);
17926a79 DH	128	local->debug_id = atomic_inc_return(&rxrpc_debug_id);
17926a79 DH	129	memcpy(&local->srx, srx, sizeof(*srx));
28036f44	130	local->srx.srx_service = 0;
f06cb291 DH	131	idr_init(&local->conn_ids);
	132	get_random_bytes(&tmp, sizeof(tmp));
	133	tmp &= 0x3fffffff;
	134	if (tmp == 0)
	135	tmp = 1;
	136	idr_set_cursor(&local->conn_ids, tmp);
9d35d880 DH	137	INIT_LIST_HEAD(&local->new_client_calls);
9d35d880 DH	138	spin_lock_init(&local->client_call_lock);
f06cb291	139
0fde882f	140	trace_rxrpc_local(local->debug_id, rxrpc_local_new, 1, 1);
17926a79 DH	141	}
	142
	143	_leave(" = %p", local);
	144	return local;
	145	}
	146
	147	/*
	148	* create the local socket
4f95dd78	149	* - must be called with rxrpc_local_mutex locked
17926a79	150	*/
2baec2c3	151	static int rxrpc_open_socket(struct rxrpc_local local, struct net net)
17926a79	152	{
1a9b86c9 XL	153	struct udp_tunnel_sock_cfg tuncfg = {NULL};
	154	struct sockaddr_rxrpc *srx = &local->srx;
	155	struct udp_port_cfg udp_conf = {0};
a275da62	156	struct task_struct *io_thread;
5271953c	157	struct sock *usk;
fce93494	158	int ret;
17926a79	159
75b54cb5	160	_enter("%p{%d,%d}",
1a9b86c9 XL	161	local, srx->transport_type, srx->transport.family);
	162
	163	udp_conf.family = srx->transport.family;
39cb9faa	164	udp_conf.use_udp_checksums = true;
1a9b86c9 XL	165	if (udp_conf.family == AF_INET) {
	166	udp_conf.local_ip = srx->transport.sin.sin_addr;
	167	udp_conf.local_udp_port = srx->transport.sin.sin_port;
295f830e	168	#if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
1a9b86c9 XL	169	} else {
	170	udp_conf.local_ip6 = srx->transport.sin6.sin6_addr;
	171	udp_conf.local_udp_port = srx->transport.sin6.sin6_port;
39cb9faa DH	172	udp_conf.use_udp6_tx_checksums = true;
39cb9faa DH	173	udp_conf.use_udp6_rx_checksums = true;
295f830e	174	#endif
1a9b86c9 XL	175	}
1a9b86c9 XL	176	ret = udp_sock_create(net, &udp_conf, &local->socket);
17926a79 DH	177	if (ret < 0) {
	178	_leave(" = %d [socket]", ret);
	179	return ret;
	180	}
	181
1a9b86c9	182	tuncfg.encap_type = UDP_ENCAP_RXRPC;
446b3e14	183	tuncfg.encap_rcv = rxrpc_encap_rcv;
ac56a0b4	184	tuncfg.encap_err_rcv = rxrpc_encap_err_rcv;
1a9b86c9 XL	185	tuncfg.sk_user_data = local;
	186	setup_udp_tunnel_sock(net, local->socket, &tuncfg);
	187
2cfa2271	188	/* set the socket up */
5271953c	189	usk = local->socket->sk;
5271953c	190	usk->sk_error_report = rxrpc_error_report;
2cfa2271	191
1a9b86c9	192	switch (srx->transport.family) {
37a675e7 DH	193	case AF_INET6:
37a675e7 DH	194	/* we want to receive ICMPv6 errors */
1a9b86c9	195	ip6_sock_set_recverr(usk);
17926a79	196
37a675e7 DH	197	/* Fall through and set IPv4 options too otherwise we don't get
	198	* errors from IPv4 packets sent through the IPv6 socket.
	199	*/
df561f66	200	fallthrough;
37a675e7	201	case AF_INET:
f2aeed3a	202	/* we want to receive ICMP errors */
1a9b86c9	203	ip_sock_set_recverr(usk);
f2aeed3a DH	204
f2aeed3a DH	205	/* we want to set the don't fragment bit */
1a9b86c9	206	ip_sock_set_mtu_discover(usk, IP_PMTUDISC_DO);
b604dd98 DH	207
b604dd98 DH	208	/* We want receive timestamps. */
1a9b86c9	209	sock_enable_timestamps(usk);
f2aeed3a DH	210	break;
	211
	212	default:
	213	BUG();
17926a79 DH	214	}
17926a79 DH	215
a275da62 DH	216	io_thread = kthread_run(rxrpc_io_thread, local,
	217	"krxrpcio/%u", ntohs(udp_conf.local_udp_port));
	218	if (IS_ERR(io_thread)) {
	219	ret = PTR_ERR(io_thread);
	220	goto error_sock;
	221	}
	222
8fbcc833	223	wait_for_completion(&local->io_thread_ready);
a275da62	224	local->io_thread = io_thread;
17926a79 DH	225	_leave(" = 0");
17926a79 DH	226	return 0;
a275da62 DH	227
	228	error_sock:
	229	kernel_sock_shutdown(local->socket, SHUT_RDWR);
	230	local->socket->sk->sk_user_data = NULL;
	231	sock_release(local->socket);
	232	local->socket = NULL;
	233	return ret;
17926a79 DH	234	}
	235
	236	/*
4f95dd78	237	* Look up or create a new local endpoint using the specified local address.
17926a79	238	*/
2baec2c3 DH	239	struct rxrpc_local rxrpc_lookup_local(struct net net,
2baec2c3 DH	240	const struct sockaddr_rxrpc *srx)
17926a79 DH	241	{
17926a79 DH	242	struct rxrpc_local *local;
2baec2c3	243	struct rxrpc_net *rxnet = rxrpc_net(net);
33912c26	244	struct hlist_node *cursor;
4f95dd78	245	long diff;
17926a79 DH	246	int ret;
17926a79 DH	247
75b54cb5 DH	248	_enter("{%d,%d,%pISp}",
75b54cb5 DH	249	srx->transport_type, srx->transport.family, &srx->transport);
17926a79	250
2baec2c3	251	mutex_lock(&rxnet->local_mutex);
17926a79	252
33912c26 DH	253	hlist_for_each(cursor, &rxnet->local_endpoints) {
33912c26 DH	254	local = hlist_entry(cursor, struct rxrpc_local, link);
17926a79	255
4f95dd78	256	diff = rxrpc_local_cmp_key(local, srx);
33912c26	257	if (diff != 0)
17926a79	258	continue;
4f95dd78 DH	259
	260	/* Services aren't allowed to share transport sockets, so
	261	* reject that here. It is possible that the object is dying -
	262	* but it may also still have the local transport address that
	263	* we want bound.
	264	*/
	265	if (srx->srx_service) {
	266	local = NULL;
	267	goto addr_in_use;
	268	}
17926a79	269
33912c26 DH	270	/* Found a match. We want to replace a dying object.
	271	* Attempting to bind the transport socket may still fail if
	272	* we're attempting to use a local address that the dying
	273	* object is still using.
4f95dd78	274	*/
0fde882f	275	if (!rxrpc_use_local(local, rxrpc_local_use_lookup))
4f95dd78	276	break;
17926a79	277
4f95dd78 DH	278	goto found;
4f95dd78 DH	279	}
17926a79	280
8a758d98	281	local = rxrpc_alloc_local(net, srx);
4f95dd78 DH	282	if (!local)
4f95dd78 DH	283	goto nomem;
17926a79	284
2baec2c3	285	ret = rxrpc_open_socket(local, net);
4f95dd78 DH	286	if (ret < 0)
	287	goto sock_error;
	288
33912c26 DH	289	if (cursor) {
	290	hlist_replace_rcu(cursor, &local->link);
	291	cursor->pprev = NULL;
	292	} else {
	293	hlist_add_head_rcu(&local->link, &rxnet->local_endpoints);
	294	}
17926a79	295
4f95dd78	296	found:
2baec2c3	297	mutex_unlock(&rxnet->local_mutex);
4f95dd78	298	_leave(" = %p", local);
17926a79 DH	299	return local;
17926a79 DH	300
4f95dd78 DH	301	nomem:
	302	ret = -ENOMEM;
	303	sock_error:
2baec2c3	304	mutex_unlock(&rxnet->local_mutex);
032be5f1 ED	305	if (local)
032be5f1 ED	306	call_rcu(&local->rcu, rxrpc_local_rcu);
4f95dd78 DH	307	_leave(" = %d", ret);
4f95dd78 DH	308	return ERR_PTR(ret);
17926a79	309
4f95dd78	310	addr_in_use:
2baec2c3	311	mutex_unlock(&rxnet->local_mutex);
4f95dd78 DH	312	_leave(" = -EADDRINUSE");
	313	return ERR_PTR(-EADDRINUSE);
	314	}
17926a79	315
09d2bf59 DH	316	/*
	317	* Get a ref on a local endpoint.
	318	*/
0fde882f DH	319	struct rxrpc_local rxrpc_get_local(struct rxrpc_local local,
0fde882f DH	320	enum rxrpc_local_trace why)
09d2bf59	321	{
0fde882f	322	int r, u;
09d2bf59	323
0fde882f	324	u = atomic_read(&local->active_users);
a0575429	325	__refcount_inc(&local->ref, &r);
0fde882f	326	trace_rxrpc_local(local->debug_id, why, r + 1, u);
09d2bf59 DH	327	return local;
	328	}
	329
	330	/*
	331	* Get a ref on a local endpoint unless its usage has already reached 0.
	332	*/
0fde882f DH	333	struct rxrpc_local rxrpc_get_local_maybe(struct rxrpc_local local,
0fde882f DH	334	enum rxrpc_local_trace why)
09d2bf59	335	{
0fde882f	336	int r, u;
09d2bf59	337
0fde882f DH	338	if (local && __refcount_inc_not_zero(&local->ref, &r)) {
	339	u = atomic_read(&local->active_users);
	340	trace_rxrpc_local(local->debug_id, why, r + 1, u);
	341	return local;
09d2bf59	342	}
0fde882f DH	343
0fde882f DH	344	return NULL;
09d2bf59 DH	345	}
09d2bf59 DH	346
09d2bf59 DH	347	/*
	348	* Drop a ref on a local endpoint.
	349	*/
0fde882f	350	void rxrpc_put_local(struct rxrpc_local *local, enum rxrpc_local_trace why)
09d2bf59	351	{
fac20b9e	352	unsigned int debug_id;
a0575429	353	bool dead;
0fde882f	354	int r, u;
09d2bf59 DH	355
09d2bf59 DH	356	if (local) {
fac20b9e DH	357	debug_id = local->debug_id;
fac20b9e DH	358
0fde882f	359	u = atomic_read(&local->active_users);
a0575429	360	dead = __refcount_dec_and_test(&local->ref, &r);
0fde882f	361	trace_rxrpc_local(debug_id, why, r, u);
09d2bf59	362
a0575429	363	if (dead)
730c5fd4	364	call_rcu(&local->rcu, rxrpc_local_rcu);
09d2bf59 DH	365	}
	366	}
	367
730c5fd4 DH	368	/*
	369	* Start using a local endpoint.
	370	*/
0fde882f DH	371	struct rxrpc_local rxrpc_use_local(struct rxrpc_local local,
0fde882f DH	372	enum rxrpc_local_trace why)
730c5fd4	373	{
0fde882f	374	local = rxrpc_get_local_maybe(local, rxrpc_local_get_for_use);
730c5fd4 DH	375	if (!local)
	376	return NULL;
	377
0fde882f DH	378	if (!__rxrpc_use_local(local, why)) {
0fde882f DH	379	rxrpc_put_local(local, rxrpc_local_put_for_use);
730c5fd4 DH	380	return NULL;
	381	}
	382
	383	return local;
	384	}
	385
	386	/*
	387	* Cease using a local endpoint. Once the number of active users reaches 0, we
5e6ef4f1	388	* start the closure of the transport in the I/O thread..
730c5fd4	389	*/
0fde882f	390	void rxrpc_unuse_local(struct rxrpc_local *local, enum rxrpc_local_trace why)
730c5fd4	391	{
eaa02390	392	unsigned int debug_id;
a2cf3264 DH	393	int r, u;
	394
	395	if (local) {
eaa02390	396	debug_id = local->debug_id;
a2cf3264 DH	397	r = refcount_read(&local->ref);
	398	u = atomic_dec_return(&local->active_users);
	399	trace_rxrpc_local(debug_id, why, r, u);
	400	if (u == 0)
	401	kthread_stop(local->io_thread);
	402	}
730c5fd4 DH	403	}
730c5fd4 DH	404
17926a79	405	/*
4f95dd78 DH	406	* Destroy a local endpoint's socket and then hand the record to RCU to dispose
	407	* of.
	408	*
	409	* Closing the socket cannot be done from bottom half context or RCU callback
	410	* context because it might sleep.
17926a79	411	*/
a275da62	412	void rxrpc_destroy_local(struct rxrpc_local *local)
17926a79	413	{
4f95dd78	414	struct socket *socket = local->socket;
2baec2c3	415	struct rxrpc_net *rxnet = local->rxnet;
17926a79	416
4f95dd78	417	_enter("%d", local->debug_id);
17926a79	418
d12040b6 DH	419	local->dead = true;
d12040b6 DH	420
2baec2c3	421	mutex_lock(&rxnet->local_mutex);
33912c26	422	hlist_del_init_rcu(&local->link);
2baec2c3	423	mutex_unlock(&rxnet->local_mutex);
4f95dd78	424
d12040b6 DH	425	rxrpc_clean_up_local_conns(local);
d12040b6 DH	426	rxrpc_service_connection_reaper(&rxnet->service_conn_reaper);
1e9e5c95	427	ASSERT(!local->service);
4f95dd78 DH	428
	429	if (socket) {
	430	local->socket = NULL;
	431	kernel_sock_shutdown(socket, SHUT_RDWR);
	432	socket->sk->sk_user_data = NULL;
	433	sock_release(socket);
	434	}
	435
	436	/* At this point, there should be no more packets coming in to the
	437	* local endpoint.
	438	*/
af094824 DH	439	#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
	440	rxrpc_purge_queue(&local->rx_delay_queue);
	441	#endif
a275da62	442	rxrpc_purge_queue(&local->rx_queue);
9d35d880	443	rxrpc_purge_client_connections(local);
17926a79 DH	444	}
17926a79 DH	445
4f95dd78 DH	446	/*
	447	* Destroy a local endpoint after the RCU grace period expires.
	448	*/
	449	static void rxrpc_local_rcu(struct rcu_head *rcu)
	450	{
	451	struct rxrpc_local *local = container_of(rcu, struct rxrpc_local, rcu);
17926a79	452
0fde882f	453	rxrpc_see_local(local, rxrpc_local_free);
17926a79	454	kfree(local);
17926a79 DH	455	}
	456
	457	/*
4f95dd78	458	* Verify the local endpoint list is empty by this point.
17926a79	459	*/
2baec2c3	460	void rxrpc_destroy_all_locals(struct rxrpc_net *rxnet)
17926a79	461	{
4f95dd78	462	struct rxrpc_local *local;
17926a79 DH	463
	464	_enter("");
	465
dee46364	466	flush_workqueue(rxrpc_workqueue);
17926a79	467
33912c26	468	if (!hlist_empty(&rxnet->local_endpoints)) {
2baec2c3	469	mutex_lock(&rxnet->local_mutex);
33912c26	470	hlist_for_each_entry(local, &rxnet->local_endpoints, link) {
dee46364	471	pr_err("AF_RXRPC: Leaked local %p {%d}\n",
a0575429	472	local, refcount_read(&local->ref));
dee46364	473	}
2baec2c3	474	mutex_unlock(&rxnet->local_mutex);
dee46364	475	BUG();
17926a79	476	}
17926a79	477	}