linux/net/tipc/core.c
Hoang Le 911600bf5a tipc: fix use-after-free Read in tipc_named_reinit
syzbot found the following issue on:
==================================================================
BUG: KASAN: use-after-free in tipc_named_reinit+0x94f/0x9b0
net/tipc/name_distr.c:413
Read of size 8 at addr ffff88805299a000 by task kworker/1:9/23764

CPU: 1 PID: 23764 Comm: kworker/1:9 Not tainted
5.18.0-rc4-syzkaller-00878-g17d49e6e8012 #0
Hardware name: Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
Workqueue: events tipc_net_finalize_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0xeb/0x495
mm/kasan/report.c:313
 print_report mm/kasan/report.c:429 [inline]
 kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
 tipc_named_reinit+0x94f/0x9b0 net/tipc/name_distr.c:413
 tipc_net_finalize+0x234/0x3d0 net/tipc/net.c:138
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
[...]
==================================================================

In the commit
d966ddcc38 ("tipc: fix a deadlock when flushing scheduled work"),
the cancel_work_sync() function just to make sure ONLY the work
tipc_net_finalize_work() is executing/pending on any CPU completed before
tipc namespace is destroyed through tipc_exit_net(). But this function
is not guaranteed the work is the last queued. So, the destroyed instance
may be accessed in the work which will try to enqueue later.

In order to completely fix, we re-order the calling of cancel_work_sync()
to make sure the work tipc_net_finalize_work() was last queued and it
must be completed by calling cancel_work_sync().

Reported-by: syzbot+47af19f3307fc9c5c82e@syzkaller.appspotmail.com
Fixes: d966ddcc38 ("tipc: fix a deadlock when flushing scheduled work")
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-17 11:39:10 +01:00

230 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->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;
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);
tipc_net_stop(net);
/* Make sure the tipc_net_finalize_work() finished */
cancel_work_sync(&tn->work);
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
while (atomic_read(&tn->wq_count))
cond_resched();
}
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);