[syzbot] [net?] possible deadlock in team_device_event (3)

syzbot
2024-05-09T16:54:22Z

Hello,

syzbot found the following issue on:

HEAD commit: 7367539ad4b0 Merge tag 'cxl-fixes-6.9-rc7' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17c0a004980000
kernel config: https://syzkaller.appspot.com/x/.config?x=3310e643b6ef5d69
dashboard link: https://syzkaller.appspot.com/bug?extid=b668da2bc4cb9670bf58
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8b1efa4e7ecb/disk-7367539a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ba7142036852/vmlinux-7367539a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/17af3ae89832/bzImage-7367539a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b668da2bc4cb9670bf58@syzkaller.appspotmail.com

mac80211_hwsim hwsim28 wlan0 (unregistering): left allmulticast mode
======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc6-syzkaller-00234-g7367539ad4b0 #0 Not tainted
------------------------------------------------------
kworker/u8:9/5208 is trying to acquire lock:
ffff88806325cd20 (team->team_lock_key#12){+.+.}-{3:3}, at: team_port_change_check drivers/net/team/team.c:2995 [inline]
ffff88806325cd20 (team->team_lock_key#12){+.+.}-{3:3}, at: team_device_event+0x11d/0x770 drivers/net/team/team.c:3021

but task is already holding lock:
ffff888051578768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5953 [inline]
ffff888051578768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: ieee80211_remove_interfaces+0xfe/0x760 net/mac80211/iface.c:2277

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&rdev->wiphy.mtx){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
wiphy_lock include/net/cfg80211.h:5953 [inline]
cfg80211_netdev_notifier_call+0x367/0x1110 net/wireless/core.c:1524
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
call_netdevice_notifiers net/core/dev.c:2002 [inline]
dev_open net/core/dev.c:1471 [inline]
dev_open+0x144/0x160 net/core/dev.c:1459
team_port_add drivers/net/team/team.c:1214 [inline]
team_add_slave+0xadc/0x2110 drivers/net/team/team.c:1974
do_set_master+0x1bc/0x230 net/core/rtnetlink.c:2685
do_setlink+0xcaf/0x3ff0 net/core/rtnetlink.c:2891
__rtnl_newlink+0xc35/0x1960 net/core/rtnetlink.c:3680
rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3727
rtnetlink_rcv_msg+0x3c7/0xe60 net/core/rtnetlink.c:6595
netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2559
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x542/0x820 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0xab5/0xc90 net/socket.c:2584
___sys_sendmsg+0x135/0x1e0 net/socket.c:2638
__sys_sendmsg+0x117/0x1f0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (team->team_lock_key#12){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
team_port_change_check drivers/net/team/team.c:2995 [inline]
team_device_event+0x11d/0x770 drivers/net/team/team.c:3021
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
call_netdevice_notifiers net/core/dev.c:2002 [inline]
dev_close_many+0x333/0x6a0 net/core/dev.c:1543
unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11080
macvlan_device_event+0x4ed/0x880 drivers/net/macvlan.c:1828
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
call_netdevice_notifiers net/core/dev.c:2002 [inline]
unregister_netdevice_many_notify+0x8a1/0x19f0 net/core/dev.c:11105
unregister_netdevice_many net/core/dev.c:11163 [inline]
unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11042
unregister_netdevice include/linux/netdevice.h:3115 [inline]
_cfg80211_unregister_wdev+0x624/0x7f0 net/wireless/core.c:1206
ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2302
ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1652
mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5560 [inline]
hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6437
ops_exit_list+0xb0/0x180 net/core/net_namespace.c:170
cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:637
process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3267
process_scheduled_works kernel/workqueue.c:3348 [inline]
worker_thread+0x6c8/0xf70 kernel/workqueue.c:3429
kthread+0x2c1/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&rdev->wiphy.mtx);
lock(team->team_lock_key#12);
lock(&rdev->wiphy.mtx);
lock(team->team_lock_key#12);

*** DEADLOCK ***

5 locks held by kworker/u8:9/5208:
#0: ffff888015ecb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1296/0x1ac0 kernel/workqueue.c:3242
#1: ffffc90003e5fd80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x906/0x1ac0 kernel/workqueue.c:3243
#2: ffffffff8f2ec950 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xbf0 net/core/net_namespace.c:591
#3: ffffffff8f301748 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_unregister_hw+0x4d/0x3a0 net/mac80211/main.c:1645
#4: ffff888051578768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5953 [inline]
#4: ffff888051578768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: ieee80211_remove_interfaces+0xfe/0x760 net/mac80211/iface.c:2277

stack backtrace:
CPU: 1 PID: 5208 Comm: kworker/u8:9 Not tainted 6.9.0-rc6-syzkaller-00234-g7367539ad4b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: netns cleanup_net
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
team_port_change_check drivers/net/team/team.c:2995 [inline]
team_device_event+0x11d/0x770 drivers/net/team/team.c:3021
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
call_netdevice_notifiers net/core/dev.c:2002 [inline]
dev_close_many+0x333/0x6a0 net/core/dev.c:1543
unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11080
macvlan_device_event+0x4ed/0x880 drivers/net/macvlan.c:1828
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
call_netdevice_notifiers net/core/dev.c:2002 [inline]
unregister_netdevice_many_notify+0x8a1/0x19f0 net/core/dev.c:11105
unregister_netdevice_many net/core/dev.c:11163 [inline]
unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11042
unregister_netdevice include/linux/netdevice.h:3115 [inline]
_cfg80211_unregister_wdev+0x624/0x7f0 net/wireless/core.c:1206
ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2302
ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1652
mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5560 [inline]
hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6437
ops_exit_list+0xb0/0x180 net/core/net_namespace.c:170
cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:637
process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3267
process_scheduled_works kernel/workqueue.c:3348 [inline]
worker_thread+0x6c8/0xf70 kernel/workqueue.c:3429
kthread+0x2c1/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
team0: Port device macvlan2 removed
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
team0 (unregistering): Port device virt_wifi0 removed
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed

---
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