vhci_hcd vhci_hcd.0: devid(0) speed(1) speed_str(low-speed)
vhci_hcd: connection closed
vhci_hcd: connection closed
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
vhci_hcd: disconnect device
BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0
IP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
IP: kthread_stop+0x47/0x640 kernel/kthread.c:525
PGD a0b81067 P4D a0b81067 PUD a0b82067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 25 Comm: kworker/u4:2 Not tainted 4.14.210-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usbip_event event_handler
task: ffff8880b567e6c0 task.stack: ffff8880b5680000
RIP: 0010:atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
RIP: 0010:kthread_stop+0x47/0x640 kernel/kthread.c:525
RSP: 0018:ffff8880b5687c70 EFLAGS: 00010297
RAX: ffff8880b567e6c0 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000286
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
RBP: fffffffffffffffc R08: ffffffff8b993010 R09: 0000000000000000
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888237e308d8
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
R13: ffff888237e308c8 R14: fffffbfff1924130 R15: ffffffff89857e40
FS:  0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000001c CR3: 00000000a0b80000 CR4: 00000000001406f0
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:1035
 event_handler+0x1c3/0x4a0 drivers/usb/usbip/usbip_event.c:92
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready
batman_adv: batadv0: Interface activated: batadv_slave_0
 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: 
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
00 65 8b 1d bc 17 c9 7e 83 fb 07 0f 87 5b 04 00 00 e8 be d5 1e 00 89 db 48 0f a3 1d 0c 42 d0 08 0f 82 a2 03 00 00 e8 a9 d5 1e 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: ffff8880b5687c70
RIP: kthread_stop+0x47/0x640 kernel/kthread.c:525 RSP: ffff8880b5687c70
CR2: 000000000000001c
---[ end trace edfccc17fd4d821d ]---