------------[ cut here ]------------ ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 include/linux/find.h:144 WARNING: CPU: 0 PID: 6936 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Modules linked in: CPU: 0 PID: 6936 Comm: kworker/u4:1 Not tainted 5.15.0-rc7-next-20211029-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd 80 4e bf 89 4c 89 ee 48 c7 c7 80 42 bf 89 e8 88 85 2e 05 <0f> 0b 83 05 45 cf 9f 09 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffc900036e7810 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: ffff8880714d3a80 RSI: ffffffff815f3788 RDI: fffff520006dcef4 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ed55e R11: 0000000000000000 R12: ffffffff896df2e0 R13: ffffffff89bf48c0 R14: ffffffff81662ee0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000563d40b90030 CR3: 0000000060676000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:992 [inline] debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1023 slab_free_hook mm/slub.c:1698 [inline] slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kfree+0xf6/0x560 mm/slub.c:4561 kvfree+0x42/0x50 mm/util.c:620 device_release+0x9f/0x240 drivers/base/core.c:2230 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 netdev_run_todo+0x75a/0xa80 net/core/dev.c:10635 default_device_exit_batch+0x2ff/0x3c0 net/core/dev.c:11605 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:593 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295