syzbot

=====================================
WARNING: bad unlock balance detected!
6.3.0-rc7-syzkaller-00089-gcb0856346a60 #0 Not tainted
-------------------------------------
kworker/u5:4/5097 is trying to release lock (&conn->chan_lock) at:
[<ffffffff89aeb135>] l2cap_bredr_sig_cmd+0x875/0x9cb0 net/bluetooth/l2cap_core.c:5748
but there are no more locks to release!

other info that might help us debug this:
2 locks held by kworker/u5:4/5097:
 #0: ffff88802ad4a938 ((wq_completion)hci5#2){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363
 #1: ffffc90003eefd20 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365

stack backtrace:
CPU: 0 PID: 5097 Comm: kworker/u5:4 Not tainted 6.3.0-rc7-syzkaller-00089-gcb0856346a60 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Workqueue: hci5 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_unlock_imbalance_bug+0x252/0x2c0 kernel/locking/lockdep.c:5109
 __lock_release kernel/locking/lockdep.c:5346 [inline]
 lock_release+0x59d/0x9d0 kernel/locking/lockdep.c:5689
 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:907
 l2cap_bredr_sig_cmd+0x875/0x9cb0 net/bluetooth/l2cap_core.c:5748
 l2cap_sig_channel net/bluetooth/l2cap_core.c:6507 [inline]
 l2cap_recv_frame+0xa5a/0x8990 net/bluetooth/l2cap_core.c:7786
 hci_acldata_packet net/bluetooth/hci_core.c:3828 [inline]
 hci_rx_work+0x58e/0xa90 net/bluetooth/hci_core.c:4063
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Bluetooth: Wrong link type (-22)
Bluetooth: Wrong link type (-22)