vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd vhci_hcd.0: pdev(5) rhport(1) sockfd(3) 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 syzkaller/managers/linux-4-19/kernel/./include/asm-generic/atomic-instrumented.h:109 [inline] BUG: KASAN: null-ptr-deref in kthread_stop+0x72/0x6b0 syzkaller/managers/linux-4-19/kernel/kernel/kthread.c:558 Write of size 4 at addr 000000000000001c by task kworker/u4:2/33 vhci_hcd vhci_hcd.0: pdev(1) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) CPU: 1 PID: 33 Comm: kworker/u4:2 Not tainted 4.19.172-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 syzkaller/managers/linux-4-19/kernel/lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef syzkaller/managers/linux-4-19/kernel/lib/dump_stack.c:118 kasan_report_error.cold+0x15b/0x1b9 syzkaller/managers/linux-4-19/kernel/mm/kasan/report.c:352 kasan_report+0x8f/0xa0 syzkaller/managers/linux-4-19/kernel/mm/kasan/report.c:412 atomic_inc syzkaller/managers/linux-4-19/kernel/./include/asm-generic/atomic-instrumented.h:109 [inline] kthread_stop+0x72/0x6b0 syzkaller/managers/linux-4-19/kernel/kernel/kthread.c:558 vhci_shutdown_connection+0x14e/0x280 syzkaller/managers/linux-4-19/kernel/drivers/usb/usbip/vhci_hcd.c:1023 vhci_hcd: connection closed vhci_hcd: connection closed event_handler+0x1f0/0x4f0 syzkaller/managers/linux-4-19/kernel/drivers/usb/usbip/usbip_event.c:78 process_one_work+0x864/0x1570 syzkaller/managers/linux-4-19/kernel/kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 syzkaller/managers/linux-4-19/kernel/kernel/workqueue.c:2298 kthread+0x33f/0x460 syzkaller/managers/linux-4-19/kernel/kernel/kthread.c:259 ret_from_fork+0x24/0x30 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/entry_64.S:415 ================================================================== vhci_hcd vhci_hcd.0: pdev(3) rhport(1) sockfd(3)