net/sctp/endpointola.c - kernel/msm-4.9 - Gitiles

 /* SCTP kernel reference Implementation
  * Copyright (c) 1999-2000 Cisco, Inc.
  * Copyright (c) 1999-2001 Motorola, Inc.
  * Copyright (c) 2001-2002 International Business Machines, Corp.
  * Copyright (c) 2001 Intel Corp.
  * Copyright (c) 2001 Nokia, Inc.
  * Copyright (c) 2001 La Monte H.P. Yarroll
  *
  * This file is part of the SCTP kernel reference Implementation
  *
  * This abstraction represents an SCTP endpoint.
  *
  * This file is part of the implementation of the add-IP extension,
  * based on <draft-ietf-tsvwg-addip-sctp-02.txt> June 29, 2001,
  * for the SCTP kernel reference Implementation.
  *
  * The SCTP reference implementation is free software;
  * you can redistribute it and/or modify it under the terms of
  * the GNU General Public License as published by
  * the Free Software Foundation; either version 2, or (at your option)
  * any later version.
  *
  * The SCTP reference implementation is distributed in the hope that it
  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  *                 ************************
  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  * See the GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with GNU CC; see the file COPYING.  If not, write to
  * the Free Software Foundation, 59 Temple Place - Suite 330,
  * Boston, MA 02111-1307, USA.
  *
  * Please send any bug reports or fixes you make to the
  * email address(es):
  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  *
  * Or submit a bug report through the following website:
  *    http://www.sf.net/projects/lksctp
  *
  * Written or modified by:
  *    La Monte H.P. Yarroll <piggy@acm.org>
  *    Karl Knutson <karl@athena.chicago.il.us>
  *    Jon Grimm <jgrimm@austin.ibm.com>
  *    Daisy Chang <daisyc@us.ibm.com>
  *    Dajiang Zhang <dajiang.zhang@nokia.com>
  *
  * Any bugs reported given to us we will try to fix... any fixes shared will
  * be incorporated into the next SCTP release.
  */

 #include <linux/types.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/in.h>
 #include <linux/random.h>	/* get_random_bytes() */
 #include <linux/crypto.h>
 #include <net/sock.h>
 #include <net/ipv6.h>
 #include <net/sctp/sctp.h>
 #include <net/sctp/sm.h>

 /* Forward declarations for internal helpers. */
 static void sctp_endpoint_bh_rcv(struct work_struct *work);

 /*
  * Initialize the base fields of the endpoint structure.
  */
 static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
 						struct sock *sk,
 						gfp_t gfp)
 {
 	memset(ep, 0, sizeof(struct sctp_endpoint));

 	ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
 	if (!ep->digest)
 		return NULL;

 	/* Initialize the base structure. */
 	/* What type of endpoint are we?  */
 	ep->base.type = SCTP_EP_TYPE_SOCKET;

 	/* Initialize the basic object fields. */
 	atomic_set(&ep->base.refcnt, 1);
 	ep->base.dead = 0;
 	ep->base.malloced = 1;

 	/* Create an input queue.  */
 	sctp_inq_init(&ep->base.inqueue);

 	/* Set its top-half handler */
 	sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);

 	/* Initialize the bind addr area */
 	sctp_bind_addr_init(&ep->base.bind_addr, 0);
 	rwlock_init(&ep->base.addr_lock);

 	/* Remember who we are attached to.  */
 	ep->base.sk = sk;
 	sock_hold(ep->base.sk);

 	/* Create the lists of associations.  */
 	INIT_LIST_HEAD(&ep->asocs);

 	/* Use SCTP specific send buffer space queues.  */
 	ep->sndbuf_policy = sctp_sndbuf_policy;
 	sk->sk_write_space = sctp_write_space;
 	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);

 	/* Get the receive buffer policy for this endpoint */
 	ep->rcvbuf_policy = sctp_rcvbuf_policy;

 	/* Initialize the secret key used with cookie. */
 	get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
 	ep->last_key = ep->current_key = 0;
 	ep->key_changed_at = jiffies;

 	return ep;
 }

 /* Create a sctp_endpoint with all that boring stuff initialized.
  * Returns NULL if there isn't enough memory.
  */
 struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
 {
 	struct sctp_endpoint *ep;

 	/* Build a local endpoint. */
 	ep = t_new(struct sctp_endpoint, gfp);
 	if (!ep)
 		goto fail;
 	if (!sctp_endpoint_init(ep, sk, gfp))
 		goto fail_init;
 	ep->base.malloced = 1;
 	SCTP_DBG_OBJCNT_INC(ep);
 	return ep;

 fail_init:
 	kfree(ep);
 fail:
 	return NULL;
 }

 /* Add an association to an endpoint.  */
 void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
 			    struct sctp_association *asoc)
 {
 	struct sock *sk = ep->base.sk;

 	/* If this is a temporary association, don't bother
 	 * since we'll be removing it shortly and don't
 	 * want anyone to find it anyway.
 	 */
 	if (asoc->temp)
 		return;

 	/* Now just add it to our list of asocs */
 	list_add_tail(&asoc->asocs, &ep->asocs);

 	/* Increment the backlog value for a TCP-style listening socket. */
 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
 		sk->sk_ack_backlog++;
 }

 /* Free the endpoint structure.  Delay cleanup until
  * all users have released their reference count on this structure.
  */
 void sctp_endpoint_free(struct sctp_endpoint *ep)
 {
 	ep->base.dead = 1;

 	ep->base.sk->sk_state = SCTP_SS_CLOSED;

 	/* Unlink this endpoint, so we can't find it again! */
 	sctp_unhash_endpoint(ep);

 	sctp_endpoint_put(ep);
 }

 /* Final destructor for endpoint.  */
 static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
 {
 	SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);

 	/* Free up the HMAC transform. */
 	crypto_free_hash(sctp_sk(ep->base.sk)->hmac);

 	/* Free the digest buffer */
 	kfree(ep->digest);

 	/* Cleanup. */
 	sctp_inq_free(&ep->base.inqueue);
 	sctp_bind_addr_free(&ep->base.bind_addr);

 	/* Remove and free the port */
 	if (sctp_sk(ep->base.sk)->bind_hash)
 		sctp_put_port(ep->base.sk);

 	/* Give up our hold on the sock. */
 	if (ep->base.sk)
 		sock_put(ep->base.sk);

 	/* Finally, free up our memory. */
 	if (ep->base.malloced) {
 		kfree(ep);
 		SCTP_DBG_OBJCNT_DEC(ep);
 	}
 }

 /* Hold a reference to an endpoint. */
 void sctp_endpoint_hold(struct sctp_endpoint *ep)
 {
 	atomic_inc(&ep->base.refcnt);
 }

 /* Release a reference to an endpoint and clean up if there are
  * no more references.
  */
 void sctp_endpoint_put(struct sctp_endpoint *ep)
 {
 	if (atomic_dec_and_test(&ep->base.refcnt))
 		sctp_endpoint_destroy(ep);
 }

 /* Is this the endpoint we are looking for?  */
 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
 					       const union sctp_addr *laddr)
 {
 	struct sctp_endpoint *retval;

 	sctp_read_lock(&ep->base.addr_lock);
 	if (htons(ep->base.bind_addr.port) == laddr->v4.sin_port) {
 		if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
 					 sctp_sk(ep->base.sk))) {
 			retval = ep;
 			goto out;
 		}
 	}

 	retval = NULL;

 out:
 	sctp_read_unlock(&ep->base.addr_lock);
 	return retval;
 }

 /* Find the association that goes with this chunk.
  * We do a linear search of the associations for this endpoint.
  * We return the matching transport address too.
  */
 static struct sctp_association *__sctp_endpoint_lookup_assoc(
 	const struct sctp_endpoint *ep,
 	const union sctp_addr *paddr,
 	struct sctp_transport **transport)
 {
 	int rport;
 	struct sctp_association *asoc;
 	struct list_head *pos;

 	rport = ntohs(paddr->v4.sin_port);

 	list_for_each(pos, &ep->asocs) {
 		asoc = list_entry(pos, struct sctp_association, asocs);
 		if (rport == asoc->peer.port) {
 			sctp_read_lock(&asoc->base.addr_lock);
 			*transport = sctp_assoc_lookup_paddr(asoc, paddr);
 			sctp_read_unlock(&asoc->base.addr_lock);

 			if (*transport)
 				return asoc;
 		}
 	}

 	*transport = NULL;
 	return NULL;
 }

 /* Lookup association on an endpoint based on a peer address.  BH-safe.  */
 struct sctp_association *sctp_endpoint_lookup_assoc(
 	const struct sctp_endpoint *ep,
 	const union sctp_addr *paddr,
 	struct sctp_transport **transport)
 {
 	struct sctp_association *asoc;

 	sctp_local_bh_disable();
 	asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
 	sctp_local_bh_enable();

 	return asoc;
 }

 /* Look for any peeled off association from the endpoint that matches the
  * given peer address.
  */
 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
 				const union sctp_addr *paddr)
 {
 	struct list_head *pos;
 	struct sctp_sockaddr_entry *addr;
 	struct sctp_bind_addr *bp;

 	sctp_read_lock(&ep->base.addr_lock);
 	bp = &ep->base.bind_addr;
 	list_for_each(pos, &bp->address_list) {
 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 		if (sctp_has_association(&addr->a, paddr)) {
 			sctp_read_unlock(&ep->base.addr_lock);
 			return 1;
 		}
 	}
 	sctp_read_unlock(&ep->base.addr_lock);

 	return 0;
 }

 /* Do delayed input processing.  This is scheduled by sctp_rcv().
  * This may be called on BH or task time.
  */
 static void sctp_endpoint_bh_rcv(struct work_struct *work)
 {
 	struct sctp_endpoint *ep =
 		container_of(work, struct sctp_endpoint,
 			     base.inqueue.immediate);
 	struct sctp_association *asoc;
 	struct sock *sk;
 	struct sctp_transport *transport;
 	struct sctp_chunk *chunk;
 	struct sctp_inq *inqueue;
 	sctp_subtype_t subtype;
 	sctp_state_t state;
 	int error = 0;

 	if (ep->base.dead)
 		return;

 	asoc = NULL;
 	inqueue = &ep->base.inqueue;
 	sk = ep->base.sk;

 	while (NULL != (chunk = sctp_inq_pop(inqueue))) {
 		subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);

 		/* We might have grown an association since last we
 		 * looked, so try again.
 		 *
 		 * This happens when we've just processed our
 		 * COOKIE-ECHO chunk.
 		 */
 		if (NULL == chunk->asoc) {
 			asoc = sctp_endpoint_lookup_assoc(ep,
 							  sctp_source(chunk),
 							  &transport);
 			chunk->asoc = asoc;
 			chunk->transport = transport;
 		}

 		state = asoc ? asoc->state : SCTP_STATE_CLOSED;

 		/* Remember where the last DATA chunk came from so we
 		 * know where to send the SACK.
 		 */
 		if (asoc && sctp_chunk_is_data(chunk))
 			asoc->peer.last_data_from = chunk->transport;
 		else
 			SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);

 		if (chunk->transport)
 			chunk->transport->last_time_heard = jiffies;

 		error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
                                    ep, asoc, chunk, GFP_ATOMIC);

 		if (error && chunk)
 			chunk->pdiscard = 1;

 		/* Check to see if the endpoint is freed in response to
 		 * the incoming chunk. If so, get out of the while loop.
 		 */
 		if (!sctp_sk(sk)->ep)
 			break;
 	}
 }
	/* SCTP kernel reference Implementation
	* Copyright (c) 1999-2000 Cisco, Inc.
	* Copyright (c) 1999-2001 Motorola, Inc.
	* Copyright (c) 2001-2002 International Business Machines, Corp.
	* Copyright (c) 2001 Intel Corp.
	* Copyright (c) 2001 Nokia, Inc.
	* Copyright (c) 2001 La Monte H.P. Yarroll
	*
	* This file is part of the SCTP kernel reference Implementation
	*
	* This abstraction represents an SCTP endpoint.
	*
	* This file is part of the implementation of the add-IP extension,
	* based on <draft-ietf-tsvwg-addip-sctp-02.txt> June 29, 2001,
	* for the SCTP kernel reference Implementation.
	*
	* The SCTP reference implementation is free software;
	* you can redistribute it and/or modify it under the terms of
	* the GNU General Public License as published by
	* the Free Software Foundation; either version 2, or (at your option)
	* any later version.
	*
	* The SCTP reference implementation is distributed in the hope that it
	* will be useful, but WITHOUT ANY WARRANTY; without even the implied
	* ************************
	* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
	* See the GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with GNU CC; see the file COPYING. If not, write to
	* the Free Software Foundation, 59 Temple Place - Suite 330,
	* Boston, MA 02111-1307, USA.
	*
	* Please send any bug reports or fixes you make to the
	* email address(es):
	* lksctp developers <lksctp-developers@lists.sourceforge.net>
	*
	* Or submit a bug report through the following website:
	* http://www.sf.net/projects/lksctp
	*
	* Written or modified by:
	* La Monte H.P. Yarroll <piggy@acm.org>
	* Karl Knutson <karl@athena.chicago.il.us>
	* Jon Grimm <jgrimm@austin.ibm.com>
	* Daisy Chang <daisyc@us.ibm.com>
	* Dajiang Zhang <dajiang.zhang@nokia.com>
	*
	* Any bugs reported given to us we will try to fix... any fixes shared will
	* be incorporated into the next SCTP release.
	*/

	#include <linux/types.h>
	#include <linux/sched.h>
	#include <linux/slab.h>
	#include <linux/in.h>
	#include <linux/random.h> /* get_random_bytes() */
	#include <linux/crypto.h>
	#include <net/sock.h>
	#include <net/ipv6.h>
	#include <net/sctp/sctp.h>
	#include <net/sctp/sm.h>

	/* Forward declarations for internal helpers. */
	static void sctp_endpoint_bh_rcv(struct work_struct *work);

	/*
	* Initialize the base fields of the endpoint structure.
	*/
	static struct sctp_endpoint sctp_endpoint_init(struct sctp_endpoint ep,
	struct sock *sk,
	gfp_t gfp)
	{
	memset(ep, 0, sizeof(struct sctp_endpoint));

	ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
	if (!ep->digest)
	return NULL;

	/* Initialize the base structure. */
	/* What type of endpoint are we? */
	ep->base.type = SCTP_EP_TYPE_SOCKET;

	/* Initialize the basic object fields. */
	atomic_set(&ep->base.refcnt, 1);
	ep->base.dead = 0;
	ep->base.malloced = 1;

	/* Create an input queue. */
	sctp_inq_init(&ep->base.inqueue);

	/* Set its top-half handler */
	sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);

	/* Initialize the bind addr area */
	sctp_bind_addr_init(&ep->base.bind_addr, 0);
	rwlock_init(&ep->base.addr_lock);

	/* Remember who we are attached to. */
	ep->base.sk = sk;
	sock_hold(ep->base.sk);

	/* Create the lists of associations. */
	INIT_LIST_HEAD(&ep->asocs);

	/* Use SCTP specific send buffer space queues. */
	ep->sndbuf_policy = sctp_sndbuf_policy;
	sk->sk_write_space = sctp_write_space;
	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);

	/* Get the receive buffer policy for this endpoint */
	ep->rcvbuf_policy = sctp_rcvbuf_policy;

	/* Initialize the secret key used with cookie. */
	get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
	ep->last_key = ep->current_key = 0;
	ep->key_changed_at = jiffies;

	return ep;
	}

	/* Create a sctp_endpoint with all that boring stuff initialized.
	* Returns NULL if there isn't enough memory.
	*/
	struct sctp_endpoint sctp_endpoint_new(struct sock sk, gfp_t gfp)
	{
	struct sctp_endpoint *ep;

	/* Build a local endpoint. */
	ep = t_new(struct sctp_endpoint, gfp);
	if (!ep)
	goto fail;
	if (!sctp_endpoint_init(ep, sk, gfp))
	goto fail_init;
	ep->base.malloced = 1;
	SCTP_DBG_OBJCNT_INC(ep);
	return ep;

	fail_init:
	kfree(ep);
	fail:
	return NULL;
	}

	/* Add an association to an endpoint. */
	void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
	struct sctp_association *asoc)
	{
	struct sock *sk = ep->base.sk;

	/* If this is a temporary association, don't bother
	* since we'll be removing it shortly and don't
	* want anyone to find it anyway.
	*/
	if (asoc->temp)
	return;

	/* Now just add it to our list of asocs */
	list_add_tail(&asoc->asocs, &ep->asocs);

	/* Increment the backlog value for a TCP-style listening socket. */
	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
	sk->sk_ack_backlog++;
	}

	/* Free the endpoint structure. Delay cleanup until
	* all users have released their reference count on this structure.
	*/
	void sctp_endpoint_free(struct sctp_endpoint *ep)
	{
	ep->base.dead = 1;

	ep->base.sk->sk_state = SCTP_SS_CLOSED;

	/* Unlink this endpoint, so we can't find it again! */
	sctp_unhash_endpoint(ep);

	sctp_endpoint_put(ep);
	}

	/* Final destructor for endpoint. */
	static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
	{
	SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);

	/* Free up the HMAC transform. */
	crypto_free_hash(sctp_sk(ep->base.sk)->hmac);

	/* Free the digest buffer */
	kfree(ep->digest);

	/* Cleanup. */
	sctp_inq_free(&ep->base.inqueue);
	sctp_bind_addr_free(&ep->base.bind_addr);

	/* Remove and free the port */
	if (sctp_sk(ep->base.sk)->bind_hash)
	sctp_put_port(ep->base.sk);

	/* Give up our hold on the sock. */
	if (ep->base.sk)
	sock_put(ep->base.sk);

	/* Finally, free up our memory. */
	if (ep->base.malloced) {
	kfree(ep);
	SCTP_DBG_OBJCNT_DEC(ep);
	}
	}

	/* Hold a reference to an endpoint. */
	void sctp_endpoint_hold(struct sctp_endpoint *ep)
	{
	atomic_inc(&ep->base.refcnt);
	}

	/* Release a reference to an endpoint and clean up if there are
	* no more references.
	*/
	void sctp_endpoint_put(struct sctp_endpoint *ep)
	{
	if (atomic_dec_and_test(&ep->base.refcnt))
	sctp_endpoint_destroy(ep);
	}

	/* Is this the endpoint we are looking for? */
	struct sctp_endpoint sctp_endpoint_is_match(struct sctp_endpoint ep,
	const union sctp_addr *laddr)
	{
	struct sctp_endpoint *retval;

	sctp_read_lock(&ep->base.addr_lock);
	if (htons(ep->base.bind_addr.port) == laddr->v4.sin_port) {
	if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
	sctp_sk(ep->base.sk))) {
	retval = ep;
	goto out;
	}
	}

	retval = NULL;

	out:
	sctp_read_unlock(&ep->base.addr_lock);
	return retval;
	}

	/* Find the association that goes with this chunk.
	* We do a linear search of the associations for this endpoint.
	* We return the matching transport address too.
	*/
	static struct sctp_association *__sctp_endpoint_lookup_assoc(
	const struct sctp_endpoint *ep,
	const union sctp_addr *paddr,
	struct sctp_transport **transport)
	{
	int rport;
	struct sctp_association *asoc;
	struct list_head *pos;

	rport = ntohs(paddr->v4.sin_port);

	list_for_each(pos, &ep->asocs) {
	asoc = list_entry(pos, struct sctp_association, asocs);
	if (rport == asoc->peer.port) {
	sctp_read_lock(&asoc->base.addr_lock);
	*transport = sctp_assoc_lookup_paddr(asoc, paddr);
	sctp_read_unlock(&asoc->base.addr_lock);

	if (*transport)
	return asoc;
	}
	}

	*transport = NULL;
	return NULL;
	}

	/* Lookup association on an endpoint based on a peer address. BH-safe. */
	struct sctp_association *sctp_endpoint_lookup_assoc(
	const struct sctp_endpoint *ep,
	const union sctp_addr *paddr,
	struct sctp_transport **transport)
	{
	struct sctp_association *asoc;

	sctp_local_bh_disable();
	asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
	sctp_local_bh_enable();

	return asoc;
	}

	/* Look for any peeled off association from the endpoint that matches the
	* given peer address.
	*/
	int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
	const union sctp_addr *paddr)
	{
	struct list_head *pos;
	struct sctp_sockaddr_entry *addr;
	struct sctp_bind_addr *bp;

	sctp_read_lock(&ep->base.addr_lock);
	bp = &ep->base.bind_addr;
	list_for_each(pos, &bp->address_list) {
	addr = list_entry(pos, struct sctp_sockaddr_entry, list);
	if (sctp_has_association(&addr->a, paddr)) {
	sctp_read_unlock(&ep->base.addr_lock);
	return 1;
	}
	}
	sctp_read_unlock(&ep->base.addr_lock);

	return 0;
	}

	/* Do delayed input processing. This is scheduled by sctp_rcv().
	* This may be called on BH or task time.
	*/
	static void sctp_endpoint_bh_rcv(struct work_struct *work)
	{
	struct sctp_endpoint *ep =
	container_of(work, struct sctp_endpoint,
	base.inqueue.immediate);
	struct sctp_association *asoc;
	struct sock *sk;
	struct sctp_transport *transport;
	struct sctp_chunk *chunk;
	struct sctp_inq *inqueue;
	sctp_subtype_t subtype;
	sctp_state_t state;
	int error = 0;

	if (ep->base.dead)
	return;

	asoc = NULL;
	inqueue = &ep->base.inqueue;
	sk = ep->base.sk;

	while (NULL != (chunk = sctp_inq_pop(inqueue))) {
	subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);

	/* We might have grown an association since last we
	* looked, so try again.
	*
	* This happens when we've just processed our
	* COOKIE-ECHO chunk.
	*/
	if (NULL == chunk->asoc) {
	asoc = sctp_endpoint_lookup_assoc(ep,
	sctp_source(chunk),
	&transport);
	chunk->asoc = asoc;
	chunk->transport = transport;
	}

	state = asoc ? asoc->state : SCTP_STATE_CLOSED;

	/* Remember where the last DATA chunk came from so we
	* know where to send the SACK.
	*/
	if (asoc && sctp_chunk_is_data(chunk))
	asoc->peer.last_data_from = chunk->transport;
	else
	SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);

	if (chunk->transport)
	chunk->transport->last_time_heard = jiffies;

	error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
	ep, asoc, chunk, GFP_ATOMIC);

	if (error && chunk)
	chunk->pdiscard = 1;

	/* Check to see if the endpoint is freed in response to
	* the incoming chunk. If so, get out of the while loop.
	*/
	if (!sctp_sk(sk)->ep)
	break;
	}
	}