IPVS: ftp: loaded support on port[0] = 21
vhci_hcd vhci_hcd.0: pdev(3) rhport(1) sockfd(8)
vhci_hcd vhci_hcd.0: devid(0) speed(4) speed_str(wireless)
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
Node 0 active_anon:567492kB inactive_anon:19284kB active_file:24812kB inactive_file:515408kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:240768kB dirty:1132kB writeback:0kB shmem:20228kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 221184kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no
Write of size 4 at addr 000000000000001c by task kworker/u4:3/2431

CPU: 1 PID: 2431 Comm: kworker/u4:3 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
Node 1 active_anon:0kB inactive_anon:0kB active_file:88kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:0kB dirty:4kB writeback:0kB shmem:0kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no
 event_handler+0x1f0/0x4f0 drivers/usb/usbip/usbip_event.c:78
 process_one_work+0x864/0x1570 kernel/workqueue.c:2152
Node 0 DMA free:15908kB min:204kB low:252kB high:300kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15992kB managed:15908kB mlocked:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
 kthread+0x33f/0x460 kernel/kthread.c:259
lowmem_reserve[]: 0 2693 2695 2695 2695
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
==================================================================
Node 0 DMA32 free:737448kB min:35996kB low:44992kB high:53988kB active_anon:567392kB inactive_anon:19284kB active_file:24812kB inactive_file:515408kB unevictable:0kB writepending:1080kB present:3129332kB managed:2763492kB mlocked:0kB kernel_stack:8320kB pagetables:6064kB bounce:0kB free_pcp:2060kB local_pcp:756kB free_cma:0kB
lowmem_reserve[]: 0 0 1 1 1
Node 0 Normal free:28kB min:24kB low:28kB high:32kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:1048576kB managed:2000kB mlocked:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB