linux/net/rds/tcp.c
Eric Dumazet 0cafd77dcd net: add a refcount tracker for kernel sockets
Commit ffa84b5ffb ("net: add netns refcount tracker to struct sock")
added a tracker to sockets, but did not track kernel sockets.

We still have syzbot reports hinting about netns being destroyed
while some kernel TCP sockets had not been dismantled.

This patch tracks kernel sockets, and adds a ref_tracker_dir_print()
call to net_free() right before the netns is freed.

Normally, each layer is responsible for properly releasing its
kernel sockets before last call to net_free().

This debugging facility is enabled with CONFIG_NET_NS_REFCNT_TRACKER=y

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-24 11:04:43 +01:00

758 lines
21 KiB
C

/*
* Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/in.h>
#include <linux/module.h>
#include <net/tcp.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/addrconf.h>
#include "rds.h"
#include "tcp.h"
/* only for info exporting */
static DEFINE_SPINLOCK(rds_tcp_tc_list_lock);
static LIST_HEAD(rds_tcp_tc_list);
/* rds_tcp_tc_count counts only IPv4 connections.
* rds6_tcp_tc_count counts both IPv4 and IPv6 connections.
*/
static unsigned int rds_tcp_tc_count;
#if IS_ENABLED(CONFIG_IPV6)
static unsigned int rds6_tcp_tc_count;
#endif
/* Track rds_tcp_connection structs so they can be cleaned up */
static DEFINE_SPINLOCK(rds_tcp_conn_lock);
static LIST_HEAD(rds_tcp_conn_list);
static atomic_t rds_tcp_unloading = ATOMIC_INIT(0);
static struct kmem_cache *rds_tcp_conn_slab;
static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *fpos);
static int rds_tcp_min_sndbuf = SOCK_MIN_SNDBUF;
static int rds_tcp_min_rcvbuf = SOCK_MIN_RCVBUF;
static struct ctl_table rds_tcp_sysctl_table[] = {
#define RDS_TCP_SNDBUF 0
{
.procname = "rds_tcp_sndbuf",
/* data is per-net pointer */
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = rds_tcp_skbuf_handler,
.extra1 = &rds_tcp_min_sndbuf,
},
#define RDS_TCP_RCVBUF 1
{
.procname = "rds_tcp_rcvbuf",
/* data is per-net pointer */
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = rds_tcp_skbuf_handler,
.extra1 = &rds_tcp_min_rcvbuf,
},
{ }
};
u32 rds_tcp_write_seq(struct rds_tcp_connection *tc)
{
/* seq# of the last byte of data in tcp send buffer */
return tcp_sk(tc->t_sock->sk)->write_seq;
}
u32 rds_tcp_snd_una(struct rds_tcp_connection *tc)
{
return tcp_sk(tc->t_sock->sk)->snd_una;
}
void rds_tcp_restore_callbacks(struct socket *sock,
struct rds_tcp_connection *tc)
{
rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc);
write_lock_bh(&sock->sk->sk_callback_lock);
/* done under the callback_lock to serialize with write_space */
spin_lock(&rds_tcp_tc_list_lock);
list_del_init(&tc->t_list_item);
#if IS_ENABLED(CONFIG_IPV6)
rds6_tcp_tc_count--;
#endif
if (!tc->t_cpath->cp_conn->c_isv6)
rds_tcp_tc_count--;
spin_unlock(&rds_tcp_tc_list_lock);
tc->t_sock = NULL;
sock->sk->sk_write_space = tc->t_orig_write_space;
sock->sk->sk_data_ready = tc->t_orig_data_ready;
sock->sk->sk_state_change = tc->t_orig_state_change;
sock->sk->sk_user_data = NULL;
write_unlock_bh(&sock->sk->sk_callback_lock);
}
/*
* rds_tcp_reset_callbacks() switches the to the new sock and
* returns the existing tc->t_sock.
*
* The only functions that set tc->t_sock are rds_tcp_set_callbacks
* and rds_tcp_reset_callbacks. Send and receive trust that
* it is set. The absence of RDS_CONN_UP bit protects those paths
* from being called while it isn't set.
*/
void rds_tcp_reset_callbacks(struct socket *sock,
struct rds_conn_path *cp)
{
struct rds_tcp_connection *tc = cp->cp_transport_data;
struct socket *osock = tc->t_sock;
if (!osock)
goto newsock;
/* Need to resolve a duelling SYN between peers.
* We have an outstanding SYN to this peer, which may
* potentially have transitioned to the RDS_CONN_UP state,
* so we must quiesce any send threads before resetting
* cp_transport_data. We quiesce these threads by setting
* cp_state to something other than RDS_CONN_UP, and then
* waiting for any existing threads in rds_send_xmit to
* complete release_in_xmit(). (Subsequent threads entering
* rds_send_xmit() will bail on !rds_conn_up().
*
* However an incoming syn-ack at this point would end up
* marking the conn as RDS_CONN_UP, and would again permit
* rds_send_xmi() threads through, so ideally we would
* synchronize on RDS_CONN_UP after lock_sock(), but cannot
* do that: waiting on !RDS_IN_XMIT after lock_sock() may
* end up deadlocking with tcp_sendmsg(), and the RDS_IN_XMIT
* would not get set. As a result, we set c_state to
* RDS_CONN_RESETTTING, to ensure that rds_tcp_state_change
* cannot mark rds_conn_path_up() in the window before lock_sock()
*/
atomic_set(&cp->cp_state, RDS_CONN_RESETTING);
wait_event(cp->cp_waitq, !test_bit(RDS_IN_XMIT, &cp->cp_flags));
/* reset receive side state for rds_tcp_data_recv() for osock */
cancel_delayed_work_sync(&cp->cp_send_w);
cancel_delayed_work_sync(&cp->cp_recv_w);
lock_sock(osock->sk);
if (tc->t_tinc) {
rds_inc_put(&tc->t_tinc->ti_inc);
tc->t_tinc = NULL;
}
tc->t_tinc_hdr_rem = sizeof(struct rds_header);
tc->t_tinc_data_rem = 0;
rds_tcp_restore_callbacks(osock, tc);
release_sock(osock->sk);
sock_release(osock);
newsock:
rds_send_path_reset(cp);
lock_sock(sock->sk);
rds_tcp_set_callbacks(sock, cp);
release_sock(sock->sk);
}
/* Add tc to rds_tcp_tc_list and set tc->t_sock. See comments
* above rds_tcp_reset_callbacks for notes about synchronization
* with data path
*/
void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp)
{
struct rds_tcp_connection *tc = cp->cp_transport_data;
rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc);
write_lock_bh(&sock->sk->sk_callback_lock);
/* done under the callback_lock to serialize with write_space */
spin_lock(&rds_tcp_tc_list_lock);
list_add_tail(&tc->t_list_item, &rds_tcp_tc_list);
#if IS_ENABLED(CONFIG_IPV6)
rds6_tcp_tc_count++;
#endif
if (!tc->t_cpath->cp_conn->c_isv6)
rds_tcp_tc_count++;
spin_unlock(&rds_tcp_tc_list_lock);
/* accepted sockets need our listen data ready undone */
if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready)
sock->sk->sk_data_ready = sock->sk->sk_user_data;
tc->t_sock = sock;
tc->t_cpath = cp;
tc->t_orig_data_ready = sock->sk->sk_data_ready;
tc->t_orig_write_space = sock->sk->sk_write_space;
tc->t_orig_state_change = sock->sk->sk_state_change;
sock->sk->sk_user_data = cp;
sock->sk->sk_data_ready = rds_tcp_data_ready;
sock->sk->sk_write_space = rds_tcp_write_space;
sock->sk->sk_state_change = rds_tcp_state_change;
write_unlock_bh(&sock->sk->sk_callback_lock);
}
/* Handle RDS_INFO_TCP_SOCKETS socket option. It only returns IPv4
* connections for backward compatibility.
*/
static void rds_tcp_tc_info(struct socket *rds_sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
struct rds_info_tcp_socket tsinfo;
struct rds_tcp_connection *tc;
unsigned long flags;
spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);
if (len / sizeof(tsinfo) < rds_tcp_tc_count)
goto out;
list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {
struct inet_sock *inet = inet_sk(tc->t_sock->sk);
if (tc->t_cpath->cp_conn->c_isv6)
continue;
tsinfo.local_addr = inet->inet_saddr;
tsinfo.local_port = inet->inet_sport;
tsinfo.peer_addr = inet->inet_daddr;
tsinfo.peer_port = inet->inet_dport;
tsinfo.hdr_rem = tc->t_tinc_hdr_rem;
tsinfo.data_rem = tc->t_tinc_data_rem;
tsinfo.last_sent_nxt = tc->t_last_sent_nxt;
tsinfo.last_expected_una = tc->t_last_expected_una;
tsinfo.last_seen_una = tc->t_last_seen_una;
tsinfo.tos = tc->t_cpath->cp_conn->c_tos;
rds_info_copy(iter, &tsinfo, sizeof(tsinfo));
}
out:
lens->nr = rds_tcp_tc_count;
lens->each = sizeof(tsinfo);
spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
}
#if IS_ENABLED(CONFIG_IPV6)
/* Handle RDS6_INFO_TCP_SOCKETS socket option. It returns both IPv4 and
* IPv6 connections. IPv4 connection address is returned in an IPv4 mapped
* address.
*/
static void rds6_tcp_tc_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
struct rds6_info_tcp_socket tsinfo6;
struct rds_tcp_connection *tc;
unsigned long flags;
spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);
if (len / sizeof(tsinfo6) < rds6_tcp_tc_count)
goto out;
list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {
struct sock *sk = tc->t_sock->sk;
struct inet_sock *inet = inet_sk(sk);
tsinfo6.local_addr = sk->sk_v6_rcv_saddr;
tsinfo6.local_port = inet->inet_sport;
tsinfo6.peer_addr = sk->sk_v6_daddr;
tsinfo6.peer_port = inet->inet_dport;
tsinfo6.hdr_rem = tc->t_tinc_hdr_rem;
tsinfo6.data_rem = tc->t_tinc_data_rem;
tsinfo6.last_sent_nxt = tc->t_last_sent_nxt;
tsinfo6.last_expected_una = tc->t_last_expected_una;
tsinfo6.last_seen_una = tc->t_last_seen_una;
rds_info_copy(iter, &tsinfo6, sizeof(tsinfo6));
}
out:
lens->nr = rds6_tcp_tc_count;
lens->each = sizeof(tsinfo6);
spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
}
#endif
int rds_tcp_laddr_check(struct net *net, const struct in6_addr *addr,
__u32 scope_id)
{
struct net_device *dev = NULL;
#if IS_ENABLED(CONFIG_IPV6)
int ret;
#endif
if (ipv6_addr_v4mapped(addr)) {
if (inet_addr_type(net, addr->s6_addr32[3]) == RTN_LOCAL)
return 0;
return -EADDRNOTAVAIL;
}
/* If the scope_id is specified, check only those addresses
* hosted on the specified interface.
*/
if (scope_id != 0) {
rcu_read_lock();
dev = dev_get_by_index_rcu(net, scope_id);
/* scope_id is not valid... */
if (!dev) {
rcu_read_unlock();
return -EADDRNOTAVAIL;
}
rcu_read_unlock();
}
#if IS_ENABLED(CONFIG_IPV6)
ret = ipv6_chk_addr(net, addr, dev, 0);
if (ret)
return 0;
#endif
return -EADDRNOTAVAIL;
}
static void rds_tcp_conn_free(void *arg)
{
struct rds_tcp_connection *tc = arg;
unsigned long flags;
rdsdebug("freeing tc %p\n", tc);
spin_lock_irqsave(&rds_tcp_conn_lock, flags);
if (!tc->t_tcp_node_detached)
list_del(&tc->t_tcp_node);
spin_unlock_irqrestore(&rds_tcp_conn_lock, flags);
kmem_cache_free(rds_tcp_conn_slab, tc);
}
static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp)
{
struct rds_tcp_connection *tc;
int i, j;
int ret = 0;
for (i = 0; i < RDS_MPATH_WORKERS; i++) {
tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp);
if (!tc) {
ret = -ENOMEM;
goto fail;
}
mutex_init(&tc->t_conn_path_lock);
tc->t_sock = NULL;
tc->t_tinc = NULL;
tc->t_tinc_hdr_rem = sizeof(struct rds_header);
tc->t_tinc_data_rem = 0;
conn->c_path[i].cp_transport_data = tc;
tc->t_cpath = &conn->c_path[i];
tc->t_tcp_node_detached = true;
rdsdebug("rds_conn_path [%d] tc %p\n", i,
conn->c_path[i].cp_transport_data);
}
spin_lock_irq(&rds_tcp_conn_lock);
for (i = 0; i < RDS_MPATH_WORKERS; i++) {
tc = conn->c_path[i].cp_transport_data;
tc->t_tcp_node_detached = false;
list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list);
}
spin_unlock_irq(&rds_tcp_conn_lock);
fail:
if (ret) {
for (j = 0; j < i; j++)
rds_tcp_conn_free(conn->c_path[j].cp_transport_data);
}
return ret;
}
static bool list_has_conn(struct list_head *list, struct rds_connection *conn)
{
struct rds_tcp_connection *tc, *_tc;
list_for_each_entry_safe(tc, _tc, list, t_tcp_node) {
if (tc->t_cpath->cp_conn == conn)
return true;
}
return false;
}
static void rds_tcp_set_unloading(void)
{
atomic_set(&rds_tcp_unloading, 1);
}
static bool rds_tcp_is_unloading(struct rds_connection *conn)
{
return atomic_read(&rds_tcp_unloading) != 0;
}
static void rds_tcp_destroy_conns(void)
{
struct rds_tcp_connection *tc, *_tc;
LIST_HEAD(tmp_list);
/* avoid calling conn_destroy with irqs off */
spin_lock_irq(&rds_tcp_conn_lock);
list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn))
list_move_tail(&tc->t_tcp_node, &tmp_list);
}
spin_unlock_irq(&rds_tcp_conn_lock);
list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node)
rds_conn_destroy(tc->t_cpath->cp_conn);
}
static void rds_tcp_exit(void);
static u8 rds_tcp_get_tos_map(u8 tos)
{
/* all user tos mapped to default 0 for TCP transport */
return 0;
}
struct rds_transport rds_tcp_transport = {
.laddr_check = rds_tcp_laddr_check,
.xmit_path_prepare = rds_tcp_xmit_path_prepare,
.xmit_path_complete = rds_tcp_xmit_path_complete,
.xmit = rds_tcp_xmit,
.recv_path = rds_tcp_recv_path,
.conn_alloc = rds_tcp_conn_alloc,
.conn_free = rds_tcp_conn_free,
.conn_path_connect = rds_tcp_conn_path_connect,
.conn_path_shutdown = rds_tcp_conn_path_shutdown,
.inc_copy_to_user = rds_tcp_inc_copy_to_user,
.inc_free = rds_tcp_inc_free,
.stats_info_copy = rds_tcp_stats_info_copy,
.exit = rds_tcp_exit,
.get_tos_map = rds_tcp_get_tos_map,
.t_owner = THIS_MODULE,
.t_name = "tcp",
.t_type = RDS_TRANS_TCP,
.t_prefer_loopback = 1,
.t_mp_capable = 1,
.t_unloading = rds_tcp_is_unloading,
};
static unsigned int rds_tcp_netid;
/* per-network namespace private data for this module */
struct rds_tcp_net {
struct socket *rds_tcp_listen_sock;
struct work_struct rds_tcp_accept_w;
struct ctl_table_header *rds_tcp_sysctl;
struct ctl_table *ctl_table;
int sndbuf_size;
int rcvbuf_size;
};
/* All module specific customizations to the RDS-TCP socket should be done in
* rds_tcp_tune() and applied after socket creation.
*/
bool rds_tcp_tune(struct socket *sock)
{
struct sock *sk = sock->sk;
struct net *net = sock_net(sk);
struct rds_tcp_net *rtn;
tcp_sock_set_nodelay(sock->sk);
lock_sock(sk);
/* TCP timer functions might access net namespace even after
* a process which created this net namespace terminated.
*/
if (!sk->sk_net_refcnt) {
if (!maybe_get_net(net)) {
release_sock(sk);
return false;
}
/* Update ns_tracker to current stack trace and refcounted tracker */
__netns_tracker_free(net, &sk->ns_tracker, false);
sk->sk_net_refcnt = 1;
netns_tracker_alloc(net, &sk->ns_tracker, GFP_KERNEL);
sock_inuse_add(net, 1);
}
rtn = net_generic(net, rds_tcp_netid);
if (rtn->sndbuf_size > 0) {
sk->sk_sndbuf = rtn->sndbuf_size;
sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
}
if (rtn->rcvbuf_size > 0) {
sk->sk_rcvbuf = rtn->rcvbuf_size;
sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
}
release_sock(sk);
return true;
}
static void rds_tcp_accept_worker(struct work_struct *work)
{
struct rds_tcp_net *rtn = container_of(work,
struct rds_tcp_net,
rds_tcp_accept_w);
while (rds_tcp_accept_one(rtn->rds_tcp_listen_sock) == 0)
cond_resched();
}
void rds_tcp_accept_work(struct sock *sk)
{
struct net *net = sock_net(sk);
struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
queue_work(rds_wq, &rtn->rds_tcp_accept_w);
}
static __net_init int rds_tcp_init_net(struct net *net)
{
struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
struct ctl_table *tbl;
int err = 0;
memset(rtn, 0, sizeof(*rtn));
/* {snd, rcv}buf_size default to 0, which implies we let the
* stack pick the value, and permit auto-tuning of buffer size.
*/
if (net == &init_net) {
tbl = rds_tcp_sysctl_table;
} else {
tbl = kmemdup(rds_tcp_sysctl_table,
sizeof(rds_tcp_sysctl_table), GFP_KERNEL);
if (!tbl) {
pr_warn("could not set allocate sysctl table\n");
return -ENOMEM;
}
rtn->ctl_table = tbl;
}
tbl[RDS_TCP_SNDBUF].data = &rtn->sndbuf_size;
tbl[RDS_TCP_RCVBUF].data = &rtn->rcvbuf_size;
rtn->rds_tcp_sysctl = register_net_sysctl(net, "net/rds/tcp", tbl);
if (!rtn->rds_tcp_sysctl) {
pr_warn("could not register sysctl\n");
err = -ENOMEM;
goto fail;
}
#if IS_ENABLED(CONFIG_IPV6)
rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, true);
#else
rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, false);
#endif
if (!rtn->rds_tcp_listen_sock) {
pr_warn("could not set up IPv6 listen sock\n");
#if IS_ENABLED(CONFIG_IPV6)
/* Try IPv4 as some systems disable IPv6 */
rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, false);
if (!rtn->rds_tcp_listen_sock) {
#endif
unregister_net_sysctl_table(rtn->rds_tcp_sysctl);
rtn->rds_tcp_sysctl = NULL;
err = -EAFNOSUPPORT;
goto fail;
#if IS_ENABLED(CONFIG_IPV6)
}
#endif
}
INIT_WORK(&rtn->rds_tcp_accept_w, rds_tcp_accept_worker);
return 0;
fail:
if (net != &init_net)
kfree(tbl);
return err;
}
static void rds_tcp_kill_sock(struct net *net)
{
struct rds_tcp_connection *tc, *_tc;
LIST_HEAD(tmp_list);
struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
struct socket *lsock = rtn->rds_tcp_listen_sock;
rtn->rds_tcp_listen_sock = NULL;
rds_tcp_listen_stop(lsock, &rtn->rds_tcp_accept_w);
spin_lock_irq(&rds_tcp_conn_lock);
list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
struct net *c_net = read_pnet(&tc->t_cpath->cp_conn->c_net);
if (net != c_net)
continue;
if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn)) {
list_move_tail(&tc->t_tcp_node, &tmp_list);
} else {
list_del(&tc->t_tcp_node);
tc->t_tcp_node_detached = true;
}
}
spin_unlock_irq(&rds_tcp_conn_lock);
list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node)
rds_conn_destroy(tc->t_cpath->cp_conn);
}
static void __net_exit rds_tcp_exit_net(struct net *net)
{
struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
rds_tcp_kill_sock(net);
if (rtn->rds_tcp_sysctl)
unregister_net_sysctl_table(rtn->rds_tcp_sysctl);
if (net != &init_net)
kfree(rtn->ctl_table);
}
static struct pernet_operations rds_tcp_net_ops = {
.init = rds_tcp_init_net,
.exit = rds_tcp_exit_net,
.id = &rds_tcp_netid,
.size = sizeof(struct rds_tcp_net),
};
void *rds_tcp_listen_sock_def_readable(struct net *net)
{
struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
struct socket *lsock = rtn->rds_tcp_listen_sock;
if (!lsock)
return NULL;
return lsock->sk->sk_user_data;
}
/* when sysctl is used to modify some kernel socket parameters,this
* function resets the RDS connections in that netns so that we can
* restart with new parameters. The assumption is that such reset
* events are few and far-between.
*/
static void rds_tcp_sysctl_reset(struct net *net)
{
struct rds_tcp_connection *tc, *_tc;
spin_lock_irq(&rds_tcp_conn_lock);
list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
struct net *c_net = read_pnet(&tc->t_cpath->cp_conn->c_net);
if (net != c_net || !tc->t_sock)
continue;
/* reconnect with new parameters */
rds_conn_path_drop(tc->t_cpath, false);
}
spin_unlock_irq(&rds_tcp_conn_lock);
}
static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *fpos)
{
struct net *net = current->nsproxy->net_ns;
int err;
err = proc_dointvec_minmax(ctl, write, buffer, lenp, fpos);
if (err < 0) {
pr_warn("Invalid input. Must be >= %d\n",
*(int *)(ctl->extra1));
return err;
}
if (write)
rds_tcp_sysctl_reset(net);
return 0;
}
static void rds_tcp_exit(void)
{
rds_tcp_set_unloading();
synchronize_rcu();
rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
#if IS_ENABLED(CONFIG_IPV6)
rds_info_deregister_func(RDS6_INFO_TCP_SOCKETS, rds6_tcp_tc_info);
#endif
unregister_pernet_device(&rds_tcp_net_ops);
rds_tcp_destroy_conns();
rds_trans_unregister(&rds_tcp_transport);
rds_tcp_recv_exit();
kmem_cache_destroy(rds_tcp_conn_slab);
}
module_exit(rds_tcp_exit);
static int __init rds_tcp_init(void)
{
int ret;
rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection",
sizeof(struct rds_tcp_connection),
0, 0, NULL);
if (!rds_tcp_conn_slab) {
ret = -ENOMEM;
goto out;
}
ret = rds_tcp_recv_init();
if (ret)
goto out_slab;
ret = register_pernet_device(&rds_tcp_net_ops);
if (ret)
goto out_recv;
rds_trans_register(&rds_tcp_transport);
rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
#if IS_ENABLED(CONFIG_IPV6)
rds_info_register_func(RDS6_INFO_TCP_SOCKETS, rds6_tcp_tc_info);
#endif
goto out;
out_recv:
rds_tcp_recv_exit();
out_slab:
kmem_cache_destroy(rds_tcp_conn_slab);
out:
return ret;
}
module_init(rds_tcp_init);
MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
MODULE_DESCRIPTION("RDS: TCP transport");
MODULE_LICENSE("Dual BSD/GPL");