Bluetooth: hci0: command tx timeout
------------[ cut here ]------------
refcnt < 0
WARNING: net/bluetooth/hci_conn.c:567 at hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:567, CPU#0: kworker/u5:2/5315
Modules linked in:
CPU: 0 UID: 0 PID: 5315 Comm: kworker/u5:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: hci0 hci_conn_timeout
RIP: 0010:hci_conn_timeout+0xff/0x2c0 net/bluetooth/hci_conn.c:567
Code: 48 89 df e8 03 8a 09 00 eb 07 e8 5c bb 4f f7 b0 13 0f b6 f0 48 89 df 5b 41 5c 41 5e 41 5f 5d e9 57 b9 fe ff e8 42 bb 4f f7 90 <0f> 0b 90 eb 8c 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 31 ff ff ff
RSP: 0018:ffffc9000e767a50 EFLAGS: 00010293
RAX: ffffffff8a72ed1e RBX: ffff8880388bc000 RCX: ffff88801a7ba4c0
RDX: 0000000000000000 RSI: 00000000ffffffc0 RDI: 0000000000000000
RBP: 00000000ffffffc0 R08: ffff8880388bc013 R09: 1ffff11007117802
R10: dffffc0000000000 R11: ffffed1007117803 R12: dffffc0000000000
R13: ffff888011eb3018 R14: ffff8880388bca40 R15: ffff8880388bc010
FS:  0000000000000000(0000) GS:ffff88808cf1d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005601798ff168 CR3: 0000000036dcd000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340
 worker_thread+0x89f/0xd90 kernel/workqueue.c:3421
 kthread+0x726/0x8b0 kernel/kthread.c:463
 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>