mirror of
https://github.com/torvalds/linux.git
synced 2024-11-24 13:11:40 +00:00
d966ddcc38
In the commitfdeba99b1e
("tipc: fix use-after-free in tipc_bcast_get_mode"), we're trying to make sure the tipc_net_finalize_work work item finished if it enqueued. But calling flush_scheduled_work() is not just affecting above work item but either any scheduled work. This has turned out to be overkill and caused to deadlock as syzbot reported: ====================================================== WARNING: possible circular locking dependency detected 5.9.0-rc2-next-20200828-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:6/349 is trying to acquire lock: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: flush_workqueue+0xe1/0x13e0 kernel/workqueue.c:2777 but task is already holding lock: ffffffff8a879430 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:565 [...] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pernet_ops_rwsem); lock(&sb->s_type->i_mutex_key#13); lock(pernet_ops_rwsem); lock((wq_completion)events); *** DEADLOCK *** [...] v1: To fix the original issue, we replace above calling by introducing a bit flag. When a namespace cleaned-up, bit flag is set to zero and: - tipc_net_finalize functionial just does return immediately. - tipc_net_finalize_work does not enqueue into the scheduled work queue. v2: Use cancel_work_sync() helper to make sure ONLY the tipc_net_finalize_work() stopped before releasing bcbase object. Reported-by: syzbot+d5aa7e0385f6a5d0f4fd@syzkaller.appspotmail.com Fixes:fdeba99b1e
("tipc: fix use-after-free in tipc_bcast_get_mode") Acked-by: Jon Maloy <jmaloy@redhat.com> Signed-off-by: Hoang Huu Le <hoang.h.le@dektech.com.au> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
231 lines
5.9 KiB
C
231 lines
5.9 KiB
C
/*
|
|
* net/tipc/core.c: TIPC module code
|
|
*
|
|
* Copyright (c) 2003-2006, 2013, Ericsson AB
|
|
* Copyright (c) 2005-2006, 2010-2013, Wind River Systems
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. 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.
|
|
* 3. Neither the names of the copyright holders nor the names of its
|
|
* contributors may be used to endorse or promote products derived from
|
|
* this software without specific prior written permission.
|
|
*
|
|
* Alternatively, this software may be distributed under the terms of the
|
|
* GNU General Public License ("GPL") version 2 as published by the Free
|
|
* Software Foundation.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include "core.h"
|
|
#include "name_table.h"
|
|
#include "subscr.h"
|
|
#include "bearer.h"
|
|
#include "net.h"
|
|
#include "socket.h"
|
|
#include "bcast.h"
|
|
#include "node.h"
|
|
#include "crypto.h"
|
|
|
|
#include <linux/module.h>
|
|
|
|
/* configurable TIPC parameters */
|
|
unsigned int tipc_net_id __read_mostly;
|
|
int sysctl_tipc_rmem[3] __read_mostly; /* min/default/max */
|
|
|
|
static int __net_init tipc_init_net(struct net *net)
|
|
{
|
|
struct tipc_net *tn = net_generic(net, tipc_net_id);
|
|
int err;
|
|
|
|
tn->net_id = 4711;
|
|
tn->node_addr = 0;
|
|
tn->trial_addr = 0;
|
|
tn->addr_trial_end = 0;
|
|
tn->capabilities = TIPC_NODE_CAPABILITIES;
|
|
INIT_WORK(&tn->final_work.work, tipc_net_finalize_work);
|
|
memset(tn->node_id, 0, sizeof(tn->node_id));
|
|
memset(tn->node_id_string, 0, sizeof(tn->node_id_string));
|
|
tn->mon_threshold = TIPC_DEF_MON_THRESHOLD;
|
|
get_random_bytes(&tn->random, sizeof(int));
|
|
INIT_LIST_HEAD(&tn->node_list);
|
|
spin_lock_init(&tn->node_list_lock);
|
|
|
|
#ifdef CONFIG_TIPC_CRYPTO
|
|
err = tipc_crypto_start(&tn->crypto_tx, net, NULL);
|
|
if (err)
|
|
goto out_crypto;
|
|
#endif
|
|
err = tipc_sk_rht_init(net);
|
|
if (err)
|
|
goto out_sk_rht;
|
|
|
|
err = tipc_nametbl_init(net);
|
|
if (err)
|
|
goto out_nametbl;
|
|
|
|
INIT_LIST_HEAD(&tn->dist_queue);
|
|
|
|
err = tipc_bcast_init(net);
|
|
if (err)
|
|
goto out_bclink;
|
|
|
|
err = tipc_attach_loopback(net);
|
|
if (err)
|
|
goto out_bclink;
|
|
|
|
return 0;
|
|
|
|
out_bclink:
|
|
tipc_nametbl_stop(net);
|
|
out_nametbl:
|
|
tipc_sk_rht_destroy(net);
|
|
out_sk_rht:
|
|
|
|
#ifdef CONFIG_TIPC_CRYPTO
|
|
tipc_crypto_stop(&tn->crypto_tx);
|
|
out_crypto:
|
|
#endif
|
|
return err;
|
|
}
|
|
|
|
static void __net_exit tipc_exit_net(struct net *net)
|
|
{
|
|
struct tipc_net *tn = tipc_net(net);
|
|
|
|
tipc_detach_loopback(net);
|
|
/* Make sure the tipc_net_finalize_work() finished */
|
|
cancel_work_sync(&tn->final_work.work);
|
|
tipc_net_stop(net);
|
|
|
|
tipc_bcast_stop(net);
|
|
tipc_nametbl_stop(net);
|
|
tipc_sk_rht_destroy(net);
|
|
#ifdef CONFIG_TIPC_CRYPTO
|
|
tipc_crypto_stop(&tipc_net(net)->crypto_tx);
|
|
#endif
|
|
}
|
|
|
|
static void __net_exit tipc_pernet_pre_exit(struct net *net)
|
|
{
|
|
tipc_node_pre_cleanup_net(net);
|
|
}
|
|
|
|
static struct pernet_operations tipc_pernet_pre_exit_ops = {
|
|
.pre_exit = tipc_pernet_pre_exit,
|
|
};
|
|
|
|
static struct pernet_operations tipc_net_ops = {
|
|
.init = tipc_init_net,
|
|
.exit = tipc_exit_net,
|
|
.id = &tipc_net_id,
|
|
.size = sizeof(struct tipc_net),
|
|
};
|
|
|
|
static struct pernet_operations tipc_topsrv_net_ops = {
|
|
.init = tipc_topsrv_init_net,
|
|
.exit = tipc_topsrv_exit_net,
|
|
};
|
|
|
|
static int __init tipc_init(void)
|
|
{
|
|
int err;
|
|
|
|
pr_info("Activated (version " TIPC_MOD_VER ")\n");
|
|
|
|
sysctl_tipc_rmem[0] = RCVBUF_MIN;
|
|
sysctl_tipc_rmem[1] = RCVBUF_DEF;
|
|
sysctl_tipc_rmem[2] = RCVBUF_MAX;
|
|
|
|
err = tipc_register_sysctl();
|
|
if (err)
|
|
goto out_sysctl;
|
|
|
|
err = register_pernet_device(&tipc_net_ops);
|
|
if (err)
|
|
goto out_pernet;
|
|
|
|
err = tipc_socket_init();
|
|
if (err)
|
|
goto out_socket;
|
|
|
|
err = register_pernet_device(&tipc_topsrv_net_ops);
|
|
if (err)
|
|
goto out_pernet_topsrv;
|
|
|
|
err = register_pernet_subsys(&tipc_pernet_pre_exit_ops);
|
|
if (err)
|
|
goto out_register_pernet_subsys;
|
|
|
|
err = tipc_bearer_setup();
|
|
if (err)
|
|
goto out_bearer;
|
|
|
|
err = tipc_netlink_start();
|
|
if (err)
|
|
goto out_netlink;
|
|
|
|
err = tipc_netlink_compat_start();
|
|
if (err)
|
|
goto out_netlink_compat;
|
|
|
|
pr_info("Started in single node mode\n");
|
|
return 0;
|
|
|
|
out_netlink_compat:
|
|
tipc_netlink_stop();
|
|
out_netlink:
|
|
tipc_bearer_cleanup();
|
|
out_bearer:
|
|
unregister_pernet_subsys(&tipc_pernet_pre_exit_ops);
|
|
out_register_pernet_subsys:
|
|
unregister_pernet_device(&tipc_topsrv_net_ops);
|
|
out_pernet_topsrv:
|
|
tipc_socket_stop();
|
|
out_socket:
|
|
unregister_pernet_device(&tipc_net_ops);
|
|
out_pernet:
|
|
tipc_unregister_sysctl();
|
|
out_sysctl:
|
|
pr_err("Unable to start in single node mode\n");
|
|
return err;
|
|
}
|
|
|
|
static void __exit tipc_exit(void)
|
|
{
|
|
tipc_netlink_compat_stop();
|
|
tipc_netlink_stop();
|
|
tipc_bearer_cleanup();
|
|
unregister_pernet_subsys(&tipc_pernet_pre_exit_ops);
|
|
unregister_pernet_device(&tipc_topsrv_net_ops);
|
|
tipc_socket_stop();
|
|
unregister_pernet_device(&tipc_net_ops);
|
|
tipc_unregister_sysctl();
|
|
|
|
pr_info("Deactivated\n");
|
|
}
|
|
|
|
module_init(tipc_init);
|
|
module_exit(tipc_exit);
|
|
|
|
MODULE_DESCRIPTION("TIPC: Transparent Inter Process Communication");
|
|
MODULE_LICENSE("Dual BSD/GPL");
|
|
MODULE_VERSION(TIPC_MOD_VER);
|