vhci_hcd: release socket vhci_hcd vhci_hcd.0: pdev(5) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd: disconnect device vhci_hcd: connection closed BUG: unable to handle kernel NULL pointer dereference at 000000000000001c IP: atomic_inc syzkaller/managers/linux-4-14/kernel/./arch/x86/include/asm/atomic.h:92 [inline] IP: kthread_stop+0x47/0x640 syzkaller/managers/linux-4-14/kernel/kernel/kthread.c:525 vhci_hcd vhci_hcd.0: pdev(1) rhport(0) sockfd(3) PGD 9c8e4067 P4D 9c8e4067 vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd: connection closed PUD aa066067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 0 PID: 1156 Comm: kworker/u4:4 Not tainted 4.14.218-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 vhci_hcd: connection closed Workqueue: usbip_event event_handler task: ffff8880b3414280 task.stack: ffff8880b3420000 RIP: 0010:atomic_inc syzkaller/managers/linux-4-14/kernel/./arch/x86/include/asm/atomic.h:92 [inline] RIP: 0010:kthread_stop+0x47/0x640 syzkaller/managers/linux-4-14/kernel/kernel/kthread.c:525 vhci_hcd vhci_hcd.0: pdev(3) rhport(1) sockfd(3) RSP: 0018:ffff8880b3427c70 EFLAGS: 00010297 vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd: connection closed RAX: ffff8880b3414280 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000282 RBP: fffffffffffffffc R08: ffffffff8b9c7860 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880aa1bcc98 R13: ffff8880aa1bcc88 R14: fffffbfff1924128 R15: ffffffff898581a0 FS: 0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000001c CR3: 00000000aa5f9000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vhci_shutdown_connection+0x12a/0x240 syzkaller/managers/linux-4-14/kernel/drivers/usb/usbip/vhci_hcd.c:1037 event_handler+0x1c3/0x4a0 syzkaller/managers/linux-4-14/kernel/drivers/usb/usbip/usbip_event.c:92 process_one_work+0x793/0x14a0 syzkaller/managers/linux-4-14/kernel/kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 syzkaller/managers/linux-4-14/kernel/kernel/workqueue.c:2250 kthread+0x30d/0x420 syzkaller/managers/linux-4-14/kernel/kernel/kthread.c:232 ret_from_fork+0x24/0x30 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/entry_64.S:404 Code: 00 65 8b 1d vhci_hcd vhci_hcd.0: pdev(2) rhport(1) sockfd(3) 6c vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) 2b vhci_hcd: connection closed ca 7e 83 fb 07 0f 87 5b 04 00 00 vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3) e8 vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) ce vhci_hcd: connection closed c8 1d 00 89 db 48 0f a3 1d fc 5f d1 08 0f 82 a2 03 00 00 e8 b9 c8 1d 00 ff 45 vhci_hcd: vhci_device speed not set 20 vhci_hcd vhci_hcd.0: pdev(0) rhport(1) sockfd(3) 48 vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) 8d 7d 24 48 b8 00 00 00 00 00 fc ff df 48 89 fa RIP: atomic_inc syzkaller/managers/linux-4-14/kernel/./arch/x86/include/asm/atomic.h:92 [inline] RSP: ffff8880b3427c70 RIP: kthread_stop+0x47/0x640 syzkaller/managers/linux-4-14/kernel/kernel/kthread.c:525 RSP: ffff8880b3427c70 vhci_hcd: connection closed CR2: 000000000000001c ---[ end trace f4584ab9b022976c ]---