============================================ WARNING: possible recursive locking detected 6.1.114-syzkaller #0 Not tainted -------------------------------------------- syz.2.2141/10873 is trying to acquire lock: ffff0000d9bc8d00 (team->team_lock_key#2){+.+.}-{3:3}, at: team_port_change_check+0x5c/0x230 drivers/net/team/team.c:3010 but task is already holding lock: ffff0000d9bc8d00 (team->team_lock_key#2){+.+.}-{3:3}, at: team_add_slave+0xa8/0x1f78 drivers/net/team/team.c:1986 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(team->team_lock_key#2); lock(team->team_lock_key#2); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz.2.2141/10873: #0: ffff800017ff4448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017ff4448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e8/0xd94 net/core/rtnetlink.c:6147 #1: ffff0000d9bc8d00 (team->team_lock_key#2){+.+.}-{3:3}, at: team_add_slave+0xa8/0x1f78 drivers/net/team/team.c:1986 stack backtrace: CPU: 0 PID: 10873 Comm: syz.2.2141 Not tainted 6.1.114-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 __lock_acquire+0x6310/0x7680 kernel/locking/lockdep.c:5049 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 team_port_change_check+0x5c/0x230 drivers/net/team/team.c:3010 team_device_event+0x434/0x4d0 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:455 __dev_notify_flags+0x2ac/0x534 dev_change_flags+0xc8/0x154 net/core/dev.c:8665 vlan_device_event+0x3f8/0x181c net/8021q/vlan.c:468 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:1970 [inline] call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] dev_open+0x1a4/0x23c net/core/dev.c:1498 team_port_add drivers/net/team/team.c:1217 [inline] team_add_slave+0x704/0x1f78 drivers/net/team/team.c:1987 do_set_master net/core/rtnetlink.c:2627 [inline] do_setlink+0xc14/0x3318 net/core/rtnetlink.c:2837 __rtnl_newlink net/core/rtnetlink.c:3605 [inline] rtnl_newlink+0x1424/0x1b74 net/core/rtnetlink.c:3652 rtnetlink_rcv_msg+0x72c/0xd94 net/core/rtnetlink.c:6150 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x65c/0x898 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x55c/0x848 net/socket.c:2519 ___sys_sendmsg net/socket.c:2573 [inline] __sys_sendmsg+0x26c/0x33c net/socket.c:2602 __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg net/socket.c:2609 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2609 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585