unregister_netdevice: waiting for syz_tun to become free. Usage count = 3
ref_tracker: netdev@ffff8880291ac700 has 1/2 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4528 [inline]
     netdev_tracker_alloc include/linux/netdevice.h:4540 [inline]
     netdev_get_by_index+0x79/0xb0 net/core/dev.c:1049
     fib6_nh_init+0x285/0x1e40 net/ipv6/route.c:3621
     ip6_route_info_create_nh+0x16a/0xad0 net/ipv6/route.c:3920
     addrconf_f6i_alloc+0x3b7/0x630 net/ipv6/route.c:4727
     ipv6_add_addr+0x59c/0x1110 net/ipv6/addrconf.c:1132
     inet6_addr_add+0x43c/0xb50 net/ipv6/addrconf.c:3074
     inet6_rtm_newaddr+0x9fc/0xe00 net/ipv6/addrconf.c:5095
     rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7137
     netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2575
     netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
     netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1364
     netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1919
     sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
     __sock_sendmsg net/socket.c:815 [inline]
     __sys_sendto+0x408/0x5a0 net/socket.c:2281
     __do_sys_sendto net/socket.c:2288 [inline]
     __se_sys_sendto net/socket.c:2284 [inline]
     __x64_sys_sendto+0xde/0x100 net/socket.c:2284
     do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
     do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
     entry_SYSCALL_64_after_hwframe+0x77/0x7f

ref_tracker: netdev@ffff8880291ac700 has 1/2 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4528 [inline]
     netdev_hold include/linux/netdevice.h:4557 [inline]
     ipv6_add_dev+0x50f/0x13a0 net/ipv6/addrconf.c:411
     addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3686
     notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85
     call_netdevice_notifiers_extack net/core/dev.c:2313 [inline]
     call_netdevice_notifiers net/core/dev.c:2327 [inline]
     register_netdevice+0x18a4/0x1eb0 net/core/dev.c:11541
     tun_set_iff+0x82b/0xf20 drivers/net/tun.c:2956
     __tun_chr_ioctl+0x7e5/0x1e70 drivers/net/tun.c:3239
     vfs_ioctl fs/ioctl.c:51 [inline]
     __do_sys_ioctl fs/ioctl.c:597 [inline]
     __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
     do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
     do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
     entry_SYSCALL_64_after_hwframe+0x77/0x7f