vhci_hcd vhci_hcd.0: pdev(0) rhport(1) sockfd(4)
vhci_hcd vhci_hcd.0: devid(0) speed(1) speed_str(low-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:583
Write of size 4 at addr 000000000000001c by task kworker/u4:7/9556

CPU: 1 PID: 9556 Comm: kworker/u4:7 Not tainted 4.19.179-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/0x2ef lib/dump_stack.c:118
 kasan_report_error.cold+0x15b/0x1b9 mm/kasan/report.c:352
 kasan_report+0x8f/0xa0 mm/kasan/report.c:412
 atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline]
 kthread_stop+0x72/0x6b0 kernel/kthread.c:583
 vhci_shutdown_connection+0x14e/0x280 drivers/usb/usbip/vhci_hcd.c:1023
 event_handler+0x1f0/0x4f0 drivers/usb/usbip/usbip_event.c:78
 process_one_work+0x864/0x1570 kernel/workqueue.c:2152
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
==================================================================
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 10134 Comm: syz-executor.5 Tainted: G    B             4.19.179-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0xa/0xf lib/fault-inject.c:149
 __should_failslab+0x115/0x180 mm/failslab.c:32
 should_failslab+0x5/0x10 mm/slab_common.c:1588
 slab_pre_alloc_hook mm/slab.h:424 [inline]
 slab_alloc mm/slab.c:3383 [inline]
 kmem_cache_alloc+0x277/0x370 mm/slab.c:3557
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 mmu_topup_memory_cache arch/x86/kvm/mmu.c:996 [inline]
 mmu_topup_memory_cache arch/x86/kvm/mmu.c:988 [inline]
 mmu_topup_memory_caches+0x8f/0x370 arch/x86/kvm/mmu.c:1042
 kvm_mmu_load+0x1e/0x1200 arch/x86/kvm/mmu.c:5102
 kvm_mmu_reload arch/x86/kvm/mmu.h:86 [inline]
 vcpu_enter_guest arch/x86/kvm/x86.c:7705 [inline]
 vcpu_run arch/x86/kvm/x86.c:7899 [inline]
 kvm_arch_vcpu_ioctl_run+0x4d6e/0x6e30 arch/x86/kvm/x86.c:8099
 kvm_vcpu_ioctl+0x493/0xe10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2822
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688