syzbot

netlink: 60 bytes leftover after parsing attributes in process `syz.0.17'.
device wlan1 entered promiscuous mode
team0: Port device wlan1 added
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.17/4307 is trying to acquire lock:
ffff8880278bcd00 (team->team_lock_key#2){+.+.}-{3:3}, at: team_del_slave+0x2e/0x1e0 drivers/net/team/team.c:2011

but task is already holding lock:
ffff88807dc28688 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: nl80211_del_interface+0x11c/0x350 net/wireless/nl80211.c:4116

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+0x1e3/0x2400 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       wiphy_lock include/net/cfg80211.h:5319 [inline]
       ieee80211_open+0x140/0x200 net/mac80211/iface.c:361
       __dev_open+0x2bf/0x430 net/core/dev.c:1550
       dev_open+0xa7/0x180 net/core/dev.c:1586
       team_port_add drivers/net/team/team.c:1222 [inline]
       team_add_slave+0x692/0x2780 drivers/net/team/team.c:1997
       do_set_master net/core/rtnetlink.c:2580 [inline]
       do_setlink+0xe90/0x3d60 net/core/rtnetlink.c:2791
       __rtnl_newlink net/core/rtnetlink.c:3455 [inline]
       rtnl_newlink+0x1658/0x1a50 net/core/rtnetlink.c:3577
       rtnetlink_rcv_msg+0x844/0xf30 net/core/rtnetlink.c:5687
       netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
       netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
       netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
       netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
       sock_sendmsg_nosec net/socket.c:706 [inline]
       __sock_sendmsg net/socket.c:718 [inline]
       ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
       ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
       __sys_sendmsg net/socket.c:2528 [inline]
       __do_sys_sendmsg net/socket.c:2537 [inline]
       __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (team->team_lock_key#2){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
       lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       team_del_slave+0x2e/0x1e0 drivers/net/team/team.c:2011
       team_device_event+0x38f/0x9e0 drivers/net/team/team.c:3055
       notifier_call_chain kernel/notifier.c:83 [inline]
       raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
       call_netdevice_notifiers_extack net/core/dev.c:2074 [inline]
       call_netdevice_notifiers net/core/dev.c:2088 [inline]
       unregister_netdevice_many+0x1049/0x19f0 net/core/dev.c:11160
       unregister_netdevice_queue+0x324/0x370 net/core/dev.c:11093
       unregister_netdevice include/linux/netdevice.h:3029 [inline]
       _cfg80211_unregister_wdev+0x186/0x500 net/wireless/core.c:1197
       ieee80211_if_remove+0x1bd/0x2b0 net/mac80211/iface.c:2108
       ieee80211_del_iface+0x15/0x20 net/mac80211/cfg.c:145
       rdev_del_virtual_intf net/wireless/rdev-ops.h:57 [inline]
       nl80211_del_interface+0x1ea/0x350 net/wireless/nl80211.c:4118
       genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
       genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
       genl_rcv_msg+0xcea/0xf90 net/netlink/genetlink.c:792
       netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
       genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
       netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
       netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
       netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
       sock_sendmsg_nosec net/socket.c:706 [inline]
       __sock_sendmsg net/socket.c:718 [inline]
       ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
       ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
       __sys_sendmsg net/socket.c:2528 [inline]
       __do_sys_sendmsg net/socket.c:2537 [inline]
       __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rdev->wiphy.mtx);
                               lock(team->team_lock_key#2);
                               lock(&rdev->wiphy.mtx);
  lock(team->team_lock_key#2);

 *** DEADLOCK ***

3 locks held by syz.0.17/4307:
 #0: ffffffff8d499e30 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
 #1: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x28/0x540 net/wireless/nl80211.c:14969
 #2: ffff88807dc28688 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: nl80211_del_interface+0x11c/0x350 net/wireless/nl80211.c:4116

stack backtrace:
CPU: 1 PID: 4307 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 team_del_slave+0x2e/0x1e0 drivers/net/team/team.c:2011
 team_device_event+0x38f/0x9e0 drivers/net/team/team.c:3055
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline]
 call_netdevice_notifiers net/core/dev.c:2088 [inline]
 unregister_netdevice_many+0x1049/0x19f0 net/core/dev.c:11160
 unregister_netdevice_queue+0x324/0x370 net/core/dev.c:11093
 unregister_netdevice include/linux/netdevice.h:3029 [inline]
 _cfg80211_unregister_wdev+0x186/0x500 net/wireless/core.c:1197
 ieee80211_if_remove+0x1bd/0x2b0 net/mac80211/iface.c:2108
 ieee80211_del_iface+0x15/0x20 net/mac80211/cfg.c:145
 rdev_del_virtual_intf net/wireless/rdev-ops.h:57 [inline]
 nl80211_del_interface+0x1ea/0x350 net/wireless/nl80211.c:4118
 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0xcea/0xf90 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
 __sys_sendmsg net/socket.c:2528 [inline]
 __do_sys_sendmsg net/socket.c:2537 [inline]
 __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4c38689dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff77825e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f4c38902fa0 RCX: 00007f4c38689dd9
RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000007
RBP: 00007f4c3871fd69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4c38902fac R14: 00007f4c38902fa0 R15: 00007f4c38902fa0
 </TASK>
team0: Port device wlan1 removed