kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 1 PID: 22 Comm: kworker/1:1 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
RIP: 0010:cdev_del+0x22/0x90 fs/char_dev.c:593
Code: cf 0f 1f 80 00 00 00 00 55 48 89 fd 48 83 ec 08 e8 f3 21 d4 ff 48 8d 7d 64 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 4f 48
RSP: 0018:ffff8881d932f280 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: ffff8881d7aa8300 RCX: ffffffff820ef17e
RDX: 000000000000000c RSI: ffffffff816a046d RDI: 0000000000000064
RBP: 0000000000000000 R08: ffff8881da24e000 R09: fffffbfff11ab3ae
R10: fffffbfff11ab3ad R11: ffffffff88d59d6f R12: 0000000000000000
R13: ffff8881d5b87000 R14: ffff8881cfa42000 R15: ffff8881cfa41070
FS:  0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004b564c CR3: 00000001cff65000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tty_unregister_device drivers/tty/tty_io.c:3188 [inline]
 tty_unregister_device+0x10d/0x1a0 drivers/tty/tty_io.c:3183
 hso_serial_tty_unregister drivers/net/usb/hso.c:2231 [inline]
 hso_create_bulk_serial_device drivers/net/usb/hso.c:2677 [inline]
 hso_probe.cold+0x6e/0x14c drivers/net/usb/hso.c:2943
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x104/0x210 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
 device_add+0xae6/0x16f0 drivers/base/core.c:2202
 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x104/0x210 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
 device_add+0xae6/0x16f0 drivers/base/core.c:2202
 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2537
 hub_port_connect drivers/usb/core/hub.c:5184 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
 port_event drivers/usb/core/hub.c:5470 [inline]
 hub_event+0x1df8/0x3800 drivers/usb/core/hub.c:5552
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 worker_thread+0x96/0xe20 kernel/workqueue.c:2415
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace 9135763b1b833867 ]---
RIP: 0010:cdev_del+0x22/0x90 fs/char_dev.c:593
Code: cf 0f 1f 80 00 00 00 00 55 48 89 fd 48 83 ec 08 e8 f3 21 d4 ff 48 8d 7d 64 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 4f 48