vhci_hcd vhci_hcd.0: pdev(3) rhport(1) sockfd(6)
JFS: Cannot determine volume size
vhci_hcd vhci_hcd.0: devid(0) speed(4) speed_str(wireless)
vhci_hcd: connection closed
BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
IP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
IP: kthread_stop+0x47/0x640 kernel/kthread.c:550
PGD 9fbd8067 P4D 9fbd8067 PUD 4f5c0067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 9344 Comm: kworker/u4:6 Not tainted 4.14.225-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usbip_event event_handler
Unknown ioctl -1072667469
task: ffff88804be56040 task.stack: ffff88804be68000
RIP: 0010:atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
RIP: 0010:kthread_stop+0x47/0x640 kernel/kthread.c:550
RSP: 0018:ffff88804be6fc70 EFLAGS: 00010297
RAX: ffff88804be56040 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000286
RBP: fffffffffffffffc R08: ffffffff8b9a2040 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888237da4ad8
R13: ffff888237da4ac8 R14: fffffbfff1924338 R15: ffffffff89858680
FS:  0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000001c CR3: 000000002b36a000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vhci_shutdown_connection+0x12a/0x240 drivers/usb/usbip/vhci_hcd.c:1037
 event_handler+0x1c3/0x4a0 drivers/usb/usbip/usbip_event.c:92
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 00 65 8b 1d 6c 2b ca 7e 83 fb 07 0f 87 5b 04 00 00 e8 5e cb 1d 00 89 db 48 0f a3 1d bc 67 d1 08 0f 82 a2 03 00 00 e8 49 cb 1d 00 <f0> ff 45 20 48 8d 7d 24 48 b8 00 00 00 00 00 fc ff df 48 89 fa 
RIP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline] RSP: ffff88804be6fc70
RIP: kthread_stop+0x47/0x640 kernel/kthread.c:550 RSP: ffff88804be6fc70
CR2: 000000000000001c
---[ end trace dd10a362caa56810 ]---