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linux-stable/net/rxrpc/af_rxrpc.c
David Howells 540b1c48c3 rxrpc: Fix deadlock between call creation and sendmsg/recvmsg 
All the routines by which rxrpc is accessed from the outside are serialised
by means of the socket lock (sendmsg, recvmsg, bind,
rxrpc_kernel_begin_call(), ...) and this presents a problem:

 (1) If a number of calls on the same socket are in the process of
     connection to the same peer, a maximum of four concurrent live calls
     are permitted before further calls need to wait for a slot.

 (2) If a call is waiting for a slot, it is deep inside sendmsg() or
     rxrpc_kernel_begin_call() and the entry function is holding the socket
     lock.

 (3) sendmsg() and recvmsg() or the in-kernel equivalents are prevented
     from servicing the other calls as they need to take the socket lock to
     do so.

 (4) The socket is stuck until a call is aborted and makes its slot
     available to the waiter.

Fix this by:

 (1) Provide each call with a mutex ('user_mutex') that arbitrates access
     by the users of rxrpc separately for each specific call.

 (2) Make rxrpc_sendmsg() and rxrpc_recvmsg() unlock the socket as soon as
     they've got a call and taken its mutex.

     Note that I'm returning EWOULDBLOCK from recvmsg() if MSG_DONTWAIT is
     set but someone else has the lock.  Should I instead only return
     EWOULDBLOCK if there's nothing currently to be done on a socket, and
     sleep in this particular instance because there is something to be
     done, but we appear to be blocked by the interrupt handler doing its
     ping?

 (3) Make rxrpc_new_client_call() unlock the socket after allocating a new
     call, locking its user mutex and adding it to the socket's call tree.
     The call is returned locked so that sendmsg() can add data to it
     immediately.

     From the moment the call is in the socket tree, it is subject to
     access by sendmsg() and recvmsg() - even if it isn't connected yet.

 (4) Lock new service calls in the UDP data_ready handler (in
     rxrpc_new_incoming_call()) because they may already be in the socket's
     tree and the data_ready handler makes them live immediately if a user
     ID has already been preassigned.

     Note that the new call is locked before any notifications are sent
     that it is live, so doing mutex_trylock() *ought* to always succeed.
     Userspace is prevented from doing sendmsg() on calls that are in a
     too-early state in rxrpc_do_sendmsg().

 (5) Make rxrpc_new_incoming_call() return the call with the user mutex
     held so that a ping can be scheduled immediately under it.

     Note that it might be worth moving the ping call into
     rxrpc_new_incoming_call() and then we can drop the mutex there.

 (6) Make rxrpc_accept_call() take the lock on the call it is accepting and
     release the socket after adding the call to the socket's tree.  This
     is slightly tricky as we've dequeued the call by that point and have
     to requeue it.

     Note that requeuing emits a trace event.

 (7) Make rxrpc_kernel_send_data() and rxrpc_kernel_recv_data() take the
     new mutex immediately and don't bother with the socket mutex at all.

This patch has the nice bonus that calls on the same socket are now to some
extent parallelisable.

Note that we might want to move rxrpc_service_prealloc() calls out from the
socket lock and give it its own lock, so that we don't hang progress in
other calls because we're waiting for the allocator.

We probably also want to avoid calling rxrpc_notify_socket() from within
the socket lock (rxrpc_accept_call()).

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.c.dionne@auristor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-01 09:50:58 -08:00

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/* AF_RXRPC implementation
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program 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 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/net.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/random.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/key-type.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#define CREATE_TRACE_POINTS
#include "ar-internal.h"
MODULE_DESCRIPTION("RxRPC network protocol");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_RXRPC);
unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
module_param_named(debug, rxrpc_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(debug, "RxRPC debugging mask");
static struct proto rxrpc_proto;
static const struct proto_ops rxrpc_rpc_ops;
/* local epoch for detecting local-end reset */
u32 rxrpc_epoch;
/* current debugging ID */
atomic_t rxrpc_debug_id;
/* count of skbs currently in use */
atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
struct workqueue_struct *rxrpc_workqueue;
static void rxrpc_sock_destructor(struct sock *);
/*
* see if an RxRPC socket is currently writable
*/
static inline int rxrpc_writable(struct sock *sk)
{
return atomic_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
}
/*
* wait for write bufferage to become available
*/
static void rxrpc_write_space(struct sock *sk)
{
_enter("%p", sk);
rcu_read_lock();
if (rxrpc_writable(sk)) {
struct socket_wq *wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible(&wq->wait);
sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
}
rcu_read_unlock();
}
/*
* validate an RxRPC address
*/
static int rxrpc_validate_address(struct rxrpc_sock *rx,
struct sockaddr_rxrpc *srx,
int len)
{
unsigned int tail;
if (len < sizeof(struct sockaddr_rxrpc))
return -EINVAL;
if (srx->srx_family != AF_RXRPC)
return -EAFNOSUPPORT;
if (srx->transport_type != SOCK_DGRAM)
return -ESOCKTNOSUPPORT;
len -= offsetof(struct sockaddr_rxrpc, transport);
if (srx->transport_len < sizeof(sa_family_t) ||
srx->transport_len > len)
return -EINVAL;
if (srx->transport.family != rx->family)
return -EAFNOSUPPORT;
switch (srx->transport.family) {
case AF_INET:
if (srx->transport_len < sizeof(struct sockaddr_in))
return -EINVAL;
tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
break;
#ifdef CONFIG_AF_RXRPC_IPV6
case AF_INET6:
if (srx->transport_len < sizeof(struct sockaddr_in6))
return -EINVAL;
tail = offsetof(struct sockaddr_rxrpc, transport) +
sizeof(struct sockaddr_in6);
break;
#endif
default:
return -EAFNOSUPPORT;
}
if (tail < len)
memset((void *)srx + tail, 0, len - tail);
_debug("INET: %pISp", &srx->transport);
return 0;
}
/*
* bind a local address to an RxRPC socket
*/
static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
{
struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
struct sock *sk = sock->sk;
struct rxrpc_local *local;
struct rxrpc_sock *rx = rxrpc_sk(sk);
u16 service_id = srx->srx_service;
int ret;
_enter("%p,%p,%d", rx, saddr, len);
ret = rxrpc_validate_address(rx, srx, len);
if (ret < 0)
goto error;
lock_sock(&rx->sk);
if (rx->sk.sk_state != RXRPC_UNBOUND) {
ret = -EINVAL;
goto error_unlock;
}
memcpy(&rx->srx, srx, sizeof(rx->srx));
local = rxrpc_lookup_local(&rx->srx);
if (IS_ERR(local)) {
ret = PTR_ERR(local);
goto error_unlock;
}
if (service_id) {
write_lock(&local->services_lock);
if (rcu_access_pointer(local->service))
goto service_in_use;
rx->local = local;
rcu_assign_pointer(local->service, rx);
write_unlock(&local->services_lock);
rx->sk.sk_state = RXRPC_SERVER_BOUND;
} else {
rx->local = local;
rx->sk.sk_state = RXRPC_CLIENT_BOUND;
}
release_sock(&rx->sk);
_leave(" = 0");
return 0;
service_in_use:
write_unlock(&local->services_lock);
rxrpc_put_local(local);
ret = -EADDRINUSE;
error_unlock:
release_sock(&rx->sk);
error:
_leave(" = %d", ret);
return ret;
}
/*
* set the number of pending calls permitted on a listening socket
*/
static int rxrpc_listen(struct socket *sock, int backlog)
{
struct sock *sk = sock->sk;
struct rxrpc_sock *rx = rxrpc_sk(sk);
unsigned int max, old;
int ret;
_enter("%p,%d", rx, backlog);
lock_sock(&rx->sk);
switch (rx->sk.sk_state) {
case RXRPC_UNBOUND:
ret = -EADDRNOTAVAIL;
break;
case RXRPC_SERVER_BOUND:
ASSERT(rx->local != NULL);
max = READ_ONCE(rxrpc_max_backlog);
ret = -EINVAL;
if (backlog == INT_MAX)
backlog = max;
else if (backlog < 0 || backlog > max)
break;
old = sk->sk_max_ack_backlog;
sk->sk_max_ack_backlog = backlog;
ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
if (ret == 0)
rx->sk.sk_state = RXRPC_SERVER_LISTENING;
else
sk->sk_max_ack_backlog = old;
break;
case RXRPC_SERVER_LISTENING:
if (backlog == 0) {
rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
sk->sk_max_ack_backlog = 0;
rxrpc_discard_prealloc(rx);
ret = 0;
break;
}
default:
ret = -EBUSY;
break;
}
release_sock(&rx->sk);
_leave(" = %d", ret);
return ret;
}
/**
* rxrpc_kernel_begin_call - Allow a kernel service to begin a call
* @sock: The socket on which to make the call
* @srx: The address of the peer to contact
* @key: The security context to use (defaults to socket setting)
* @user_call_ID: The ID to use
* @gfp: The allocation constraints
* @notify_rx: Where to send notifications instead of socket queue
*
* Allow a kernel service to begin a call on the nominated socket. This just
* sets up all the internal tracking structures and allocates connection and
* call IDs as appropriate. The call to be used is returned.
*
* The default socket destination address and security may be overridden by
* supplying @srx and @key.
*/
struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
struct sockaddr_rxrpc *srx,
struct key *key,
unsigned long user_call_ID,
gfp_t gfp,
rxrpc_notify_rx_t notify_rx)
{
struct rxrpc_conn_parameters cp;
struct rxrpc_call *call;
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
int ret;
_enter(",,%x,%lx", key_serial(key), user_call_ID);
ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
if (ret < 0)
return ERR_PTR(ret);
lock_sock(&rx->sk);
if (!key)
key = rx->key;
if (key && !key->payload.data[0])
key = NULL; /* a no-security key */
memset(&cp, 0, sizeof(cp));
cp.local = rx->local;
cp.key = key;
cp.security_level = 0;
cp.exclusive = false;
cp.service_id = srx->srx_service;
call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, gfp);
/* The socket has been unlocked. */
if (!IS_ERR(call))
call->notify_rx = notify_rx;
mutex_unlock(&call->user_mutex);
_leave(" = %p", call);
return call;
}
EXPORT_SYMBOL(rxrpc_kernel_begin_call);
/**
* rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
* @sock: The socket the call is on
* @call: The call to end
*
* Allow a kernel service to end a call it was using. The call must be
* complete before this is called (the call should be aborted if necessary).
*/
void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
{
_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
mutex_lock(&call->user_mutex);
rxrpc_release_call(rxrpc_sk(sock->sk), call);
mutex_unlock(&call->user_mutex);
rxrpc_put_call(call, rxrpc_call_put_kernel);
}
EXPORT_SYMBOL(rxrpc_kernel_end_call);
/**
* rxrpc_kernel_new_call_notification - Get notifications of new calls
* @sock: The socket to intercept received messages on
* @notify_new_call: Function to be called when new calls appear
* @discard_new_call: Function to discard preallocated calls
*
* Allow a kernel service to be given notifications about new calls.
*/
void rxrpc_kernel_new_call_notification(
struct socket *sock,
rxrpc_notify_new_call_t notify_new_call,
rxrpc_discard_new_call_t discard_new_call)
{
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
rx->notify_new_call = notify_new_call;
rx->discard_new_call = discard_new_call;
}
EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
/*
* connect an RxRPC socket
* - this just targets it at a specific destination; no actual connection
* negotiation takes place
*/
static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
int addr_len, int flags)
{
struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
int ret;
_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
ret = rxrpc_validate_address(rx, srx, addr_len);
if (ret < 0) {
_leave(" = %d [bad addr]", ret);
return ret;
}
lock_sock(&rx->sk);
ret = -EISCONN;
if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
goto error;
switch (rx->sk.sk_state) {
case RXRPC_UNBOUND:
rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
case RXRPC_CLIENT_UNBOUND:
case RXRPC_CLIENT_BOUND:
break;
default:
ret = -EBUSY;
goto error;
}
rx->connect_srx = *srx;
set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
ret = 0;
error:
release_sock(&rx->sk);
return ret;
}
/*
* send a message through an RxRPC socket
* - in a client this does a number of things:
* - finds/sets up a connection for the security specified (if any)
* - initiates a call (ID in control data)
* - ends the request phase of a call (if MSG_MORE is not set)
* - sends a call data packet
* - may send an abort (abort code in control data)
*/
static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
{
struct rxrpc_local *local;
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
int ret;
_enter(",{%d},,%zu", rx->sk.sk_state, len);
if (m->msg_flags & MSG_OOB)
return -EOPNOTSUPP;
if (m->msg_name) {
ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
if (ret < 0) {
_leave(" = %d [bad addr]", ret);
return ret;
}
}
lock_sock(&rx->sk);
switch (rx->sk.sk_state) {
case RXRPC_UNBOUND:
rx->srx.srx_family = AF_RXRPC;
rx->srx.srx_service = 0;
rx->srx.transport_type = SOCK_DGRAM;
rx->srx.transport.family = rx->family;
switch (rx->family) {
case AF_INET:
rx->srx.transport_len = sizeof(struct sockaddr_in);
break;
#ifdef CONFIG_AF_RXRPC_IPV6
case AF_INET6:
rx->srx.transport_len = sizeof(struct sockaddr_in6);
break;
#endif
default:
ret = -EAFNOSUPPORT;
goto error_unlock;
}
local = rxrpc_lookup_local(&rx->srx);
if (IS_ERR(local)) {
ret = PTR_ERR(local);
goto error_unlock;
}
rx->local = local;
rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
/* Fall through */
case RXRPC_CLIENT_UNBOUND:
case RXRPC_CLIENT_BOUND:
if (!m->msg_name &&
test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
m->msg_name = &rx->connect_srx;
m->msg_namelen = sizeof(rx->connect_srx);
}
case RXRPC_SERVER_BOUND:
case RXRPC_SERVER_LISTENING:
ret = rxrpc_do_sendmsg(rx, m, len);
/* The socket has been unlocked */
goto out;
default:
ret = -EINVAL;
goto error_unlock;
}
error_unlock:
release_sock(&rx->sk);
out:
_leave(" = %d", ret);
return ret;
}
/*
* set RxRPC socket options
*/
static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
unsigned int min_sec_level;
int ret;
_enter(",%d,%d,,%d", level, optname, optlen);
lock_sock(&rx->sk);
ret = -EOPNOTSUPP;
if (level == SOL_RXRPC) {
switch (optname) {
case RXRPC_EXCLUSIVE_CONNECTION:
ret = -EINVAL;
if (optlen != 0)
goto error;
ret = -EISCONN;
if (rx->sk.sk_state != RXRPC_UNBOUND)
goto error;
rx->exclusive = true;
goto success;
case RXRPC_SECURITY_KEY:
ret = -EINVAL;
if (rx->key)
goto error;
ret = -EISCONN;
if (rx->sk.sk_state != RXRPC_UNBOUND)
goto error;
ret = rxrpc_request_key(rx, optval, optlen);
goto error;
case RXRPC_SECURITY_KEYRING:
ret = -EINVAL;
if (rx->key)
goto error;
ret = -EISCONN;
if (rx->sk.sk_state != RXRPC_UNBOUND)
goto error;
ret = rxrpc_server_keyring(rx, optval, optlen);
goto error;
case RXRPC_MIN_SECURITY_LEVEL:
ret = -EINVAL;
if (optlen != sizeof(unsigned int))
goto error;
ret = -EISCONN;
if (rx->sk.sk_state != RXRPC_UNBOUND)
goto error;
ret = get_user(min_sec_level,
(unsigned int __user *) optval);
if (ret < 0)
goto error;
ret = -EINVAL;
if (min_sec_level > RXRPC_SECURITY_MAX)
goto error;
rx->min_sec_level = min_sec_level;
goto success;
default:
break;
}
}
success:
ret = 0;
error:
release_sock(&rx->sk);
return ret;
}
/*
* permit an RxRPC socket to be polled
*/
static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
struct rxrpc_sock *rx = rxrpc_sk(sk);
unsigned int mask;
sock_poll_wait(file, sk_sleep(sk), wait);
mask = 0;
/* the socket is readable if there are any messages waiting on the Rx
* queue */
if (!list_empty(&rx->recvmsg_q))
mask |= POLLIN | POLLRDNORM;
/* the socket is writable if there is space to add new data to the
* socket; there is no guarantee that any particular call in progress
* on the socket may have space in the Tx ACK window */
if (rxrpc_writable(sk))
mask |= POLLOUT | POLLWRNORM;
return mask;
}
/*
* create an RxRPC socket
*/
static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
int kern)
{
struct rxrpc_sock *rx;
struct sock *sk;
_enter("%p,%d", sock, protocol);
if (!net_eq(net, &init_net))
return -EAFNOSUPPORT;
/* we support transport protocol UDP/UDP6 only */
if (protocol != PF_INET &&
IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
return -EPROTONOSUPPORT;
if (sock->type != SOCK_DGRAM)
return -ESOCKTNOSUPPORT;
sock->ops = &rxrpc_rpc_ops;
sock->state = SS_UNCONNECTED;
sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
if (!sk)
return -ENOMEM;
sock_init_data(sock, sk);
sock_set_flag(sk, SOCK_RCU_FREE);
sk->sk_state = RXRPC_UNBOUND;
sk->sk_write_space = rxrpc_write_space;
sk->sk_max_ack_backlog = 0;
sk->sk_destruct = rxrpc_sock_destructor;
rx = rxrpc_sk(sk);
rx->family = protocol;
rx->calls = RB_ROOT;
spin_lock_init(&rx->incoming_lock);
INIT_LIST_HEAD(&rx->sock_calls);
INIT_LIST_HEAD(&rx->to_be_accepted);
INIT_LIST_HEAD(&rx->recvmsg_q);
rwlock_init(&rx->recvmsg_lock);
rwlock_init(&rx->call_lock);
memset(&rx->srx, 0, sizeof(rx->srx));
_leave(" = 0 [%p]", rx);
return 0;
}
/*
* Kill all the calls on a socket and shut it down.
*/
static int rxrpc_shutdown(struct socket *sock, int flags)
{
struct sock *sk = sock->sk;
struct rxrpc_sock *rx = rxrpc_sk(sk);
int ret = 0;
_enter("%p,%d", sk, flags);
if (flags != SHUT_RDWR)
return -EOPNOTSUPP;
if (sk->sk_state == RXRPC_CLOSE)
return -ESHUTDOWN;
lock_sock(sk);
spin_lock_bh(&sk->sk_receive_queue.lock);
if (sk->sk_state < RXRPC_CLOSE) {
sk->sk_state = RXRPC_CLOSE;
sk->sk_shutdown = SHUTDOWN_MASK;
} else {
ret = -ESHUTDOWN;
}
spin_unlock_bh(&sk->sk_receive_queue.lock);
rxrpc_discard_prealloc(rx);
release_sock(sk);
return ret;
}
/*
* RxRPC socket destructor
*/
static void rxrpc_sock_destructor(struct sock *sk)
{
_enter("%p", sk);
rxrpc_purge_queue(&sk->sk_receive_queue);
WARN_ON(atomic_read(&sk->sk_wmem_alloc));
WARN_ON(!sk_unhashed(sk));
WARN_ON(sk->sk_socket);
if (!sock_flag(sk, SOCK_DEAD)) {
printk("Attempt to release alive rxrpc socket: %p\n", sk);
return;
}
}
/*
* release an RxRPC socket
*/
static int rxrpc_release_sock(struct sock *sk)
{
struct rxrpc_sock *rx = rxrpc_sk(sk);
_enter("%p{%d,%d}", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
/* declare the socket closed for business */
sock_orphan(sk);
sk->sk_shutdown = SHUTDOWN_MASK;
spin_lock_bh(&sk->sk_receive_queue.lock);
sk->sk_state = RXRPC_CLOSE;
spin_unlock_bh(&sk->sk_receive_queue.lock);
if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
write_lock(&rx->local->services_lock);
rcu_assign_pointer(rx->local->service, NULL);
write_unlock(&rx->local->services_lock);
}
/* try to flush out this socket */
rxrpc_discard_prealloc(rx);
rxrpc_release_calls_on_socket(rx);
flush_workqueue(rxrpc_workqueue);
rxrpc_purge_queue(&sk->sk_receive_queue);
rxrpc_put_local(rx->local);
rx->local = NULL;
key_put(rx->key);
rx->key = NULL;
key_put(rx->securities);
rx->securities = NULL;
sock_put(sk);
_leave(" = 0");
return 0;
}
/*
* release an RxRPC BSD socket on close() or equivalent
*/
static int rxrpc_release(struct socket *sock)
{
struct sock *sk = sock->sk;
_enter("%p{%p}", sock, sk);
if (!sk)
return 0;
sock->sk = NULL;
return rxrpc_release_sock(sk);
}
/*
* RxRPC network protocol
*/
static const struct proto_ops rxrpc_rpc_ops = {
.family = PF_RXRPC,
.owner = THIS_MODULE,
.release = rxrpc_release,
.bind = rxrpc_bind,
.connect = rxrpc_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = sock_no_getname,
.poll = rxrpc_poll,
.ioctl = sock_no_ioctl,
.listen = rxrpc_listen,
.shutdown = rxrpc_shutdown,
.setsockopt = rxrpc_setsockopt,
.getsockopt = sock_no_getsockopt,
.sendmsg = rxrpc_sendmsg,
.recvmsg = rxrpc_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
};
static struct proto rxrpc_proto = {
.name = "RXRPC",
.owner = THIS_MODULE,
.obj_size = sizeof(struct rxrpc_sock),
.max_header = sizeof(struct rxrpc_wire_header),
};
static const struct net_proto_family rxrpc_family_ops = {
.family = PF_RXRPC,
.create = rxrpc_create,
.owner = THIS_MODULE,
};
/*
* initialise and register the RxRPC protocol
*/
static int __init af_rxrpc_init(void)
{
int ret = -1;
unsigned int tmp;
BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
get_random_bytes(&rxrpc_epoch, sizeof(rxrpc_epoch));
rxrpc_epoch |= RXRPC_RANDOM_EPOCH;
get_random_bytes(&tmp, sizeof(tmp));
tmp &= 0x3fffffff;
if (tmp == 0)
tmp = 1;
idr_set_cursor(&rxrpc_client_conn_ids, tmp);
ret = -ENOMEM;
rxrpc_call_jar = kmem_cache_create(
"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!rxrpc_call_jar) {
pr_notice("Failed to allocate call jar\n");
goto error_call_jar;
}
rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
if (!rxrpc_workqueue) {
pr_notice("Failed to allocate work queue\n");
goto error_work_queue;
}
ret = rxrpc_init_security();
if (ret < 0) {
pr_crit("Cannot initialise security\n");
goto error_security;
}
ret = proto_register(&rxrpc_proto, 1);
if (ret < 0) {
pr_crit("Cannot register protocol\n");
goto error_proto;
}
ret = sock_register(&rxrpc_family_ops);
if (ret < 0) {
pr_crit("Cannot register socket family\n");
goto error_sock;
}
ret = register_key_type(&key_type_rxrpc);
if (ret < 0) {
pr_crit("Cannot register client key type\n");
goto error_key_type;
}
ret = register_key_type(&key_type_rxrpc_s);
if (ret < 0) {
pr_crit("Cannot register server key type\n");
goto error_key_type_s;
}
ret = rxrpc_sysctl_init();
if (ret < 0) {
pr_crit("Cannot register sysctls\n");
goto error_sysctls;
}
#ifdef CONFIG_PROC_FS
proc_create("rxrpc_calls", 0, init_net.proc_net, &rxrpc_call_seq_fops);
proc_create("rxrpc_conns", 0, init_net.proc_net,
&rxrpc_connection_seq_fops);
#endif
return 0;
error_sysctls:
unregister_key_type(&key_type_rxrpc_s);
error_key_type_s:
unregister_key_type(&key_type_rxrpc);
error_key_type:
sock_unregister(PF_RXRPC);
error_sock:
proto_unregister(&rxrpc_proto);
error_proto:
rxrpc_exit_security();
error_security:
destroy_workqueue(rxrpc_workqueue);
error_work_queue:
kmem_cache_destroy(rxrpc_call_jar);
error_call_jar:
return ret;
}
/*
* unregister the RxRPC protocol
*/
static void __exit af_rxrpc_exit(void)
{
_enter("");
rxrpc_sysctl_exit();
unregister_key_type(&key_type_rxrpc_s);
unregister_key_type(&key_type_rxrpc);
sock_unregister(PF_RXRPC);
proto_unregister(&rxrpc_proto);
rxrpc_destroy_all_calls();
rxrpc_destroy_all_connections();
ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
rxrpc_destroy_all_locals();
remove_proc_entry("rxrpc_conns", init_net.proc_net);
remove_proc_entry("rxrpc_calls", init_net.proc_net);
destroy_workqueue(rxrpc_workqueue);
rxrpc_exit_security();
kmem_cache_destroy(rxrpc_call_jar);
_leave("");
}
module_init(af_rxrpc_init);
module_exit(af_rxrpc_exit);
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