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kobject_add_internal failed for  (error: -12 parent: net)
WARNING: CPU: 1 PID: 3494 at lib/kobject.c:244 kobject_add_internal+0x3f6/0xbc0 lib/kobject.c:242
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3494 Comm: syzkaller425998 Not tainted 4.15.0-rc6+ #249
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1079
RIP: 0010:kobject_add_internal+0x3f6/0xbc0 lib/kobject.c:242
RSP: 0018:ffff8801c53c76f0 EFLAGS: 00010286
RAX: dffffc0000000008 RBX: ffff8801bf5a88d8 RCX: ffffffff8159da9e
RDX: 0000000000000000 RSI: 1ffff10038a78e99 RDI: ffff8801c53c73f8
RBP: ffff8801c53c77e8 R08: 1ffff10038a78e5b R09: 0000000000000000
R10: ffff8801c53c74b0 R11: 0000000000000000 R12: 1ffff10038a78ee4
R13: 00000000fffffff4 R14: ffff8801d8359a80 R15: ffffffff86201980
 kobject_add_varg lib/kobject.c:366 [inline]
 kobject_add+0x132/0x1f0 lib/kobject.c:411
 device_add+0x35d/0x1650 drivers/base/core.c:1787
 netdev_register_kobject+0x183/0x360 net/core/net-sysfs.c:1604
 register_netdevice+0xb2b/0x1010 net/core/dev.c:7698
 tun_set_iff drivers/net/tun.c:2319 [inline]
 __tun_chr_ioctl+0x1d89/0x3dd0 drivers/net/tun.c:2524
 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2773
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x444fc9
RSP: 002b:00007fff53389dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000444fc9
RDX: 0000000020533000 RSI: 00000000400454ca RDI: 0000000000000004
RBP: 0000000000000005 R08: 0000000000000002 R09: 0000006f00003131
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402500
R13: 0000000000402590 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..