vhci_hcd: disconnect device vhci_hcd vhci_hcd.0: pdev(1) rhport(1) sockfd(5) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd: connection closed ================================================================== BUG: KASAN: null-ptr-deref in atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline] BUG: KASAN: null-ptr-deref in kthread_stop+0x72/0x6b0 kernel/kthread.c:558 Write of size 4 at addr 000000000000001c by task kworker/u4:4/3567 CPU: 1 PID: 3567 Comm: kworker/u4:4 Not tainted 4.19.163-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usbip_event event_handler Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 kasan_report_error.cold+0x15b/0x1c7 mm/kasan/report.c:352 kasan_report+0x8f/0x96 mm/kasan/report.c:412 atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline] kthread_stop+0x72/0x6b0 kernel/kthread.c:558 vhci_shutdown_connection+0x14e/0x280 drivers/usb/usbip/vhci_hcd.c:1021 event_handler+0x1f0/0x4f0 drivers/usb/usbip/usbip_event.c:78 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 3567 Comm: kworker/u4:4 Tainted: G B 4.19.163-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usbip_event event_handler Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 panic+0x26a/0x50e kernel/panic.c:186 kasan_end_report+0x43/0x49 mm/kasan/report.c:180 kasan_report_error.cold+0xa7/0x1c7 mm/kasan/report.c:359 kasan_report+0x8f/0x96 mm/kasan/report.c:412 vhci_hcd: vhci_device speed not set atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline] kthread_stop+0x72/0x6b0 kernel/kthread.c:558 vhci_shutdown_connection+0x14e/0x280 drivers/usb/usbip/vhci_hcd.c:1021 event_handler+0x1f0/0x4f0 drivers/usb/usbip/usbip_event.c:78 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Kernel Offset: disabled Rebooting in 86400 seconds..