unregister_netdevice: waiting for syz_tun to become free. Usage count = 2
ref_tracker: netdev@ffff888023cac620 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4436 [inline]
     netdev_tracker_alloc include/linux/netdevice.h:4448 [inline]
     netdev_get_by_index+0x7c/0xb0 net/core/dev.c:1027
     fib6_nh_init+0x603/0x1c90 net/ipv6/route.c:3600
     ip6_route_info_create_nh+0x50b/0xfe0 net/ipv6/route.c:3899
     ip6_route_add+0x80/0x1d0 net/ipv6/route.c:3951
     addrconf_prefix_route+0x2fb/0x510 net/ipv6/addrconf.c:2487
     addrconf_add_linklocal+0x329/0x500 net/ipv6/addrconf.c:3312
     addrconf_addr_gen+0x364/0x3b0 net/ipv6/addrconf.c:3446
     addrconf_dev_config net/ipv6/addrconf.c:3493 [inline]
     addrconf_init_auto_addrs+0x1cb/0x780 net/ipv6/addrconf.c:3571
     addrconf_notify+0x10a6/0x19c0 net/ipv6/addrconf.c:3744
     notifier_call_chain+0x99/0x420 kernel/notifier.c:85
     call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2249
     call_netdevice_notifiers_extack net/core/dev.c:2287 [inline]
     call_netdevice_notifiers net/core/dev.c:2301 [inline]
     __dev_notify_flags+0x12c/0x2e0 net/core/dev.c:9803
     netif_change_flags+0x108/0x160 net/core/dev.c:9832
     do_setlink.isra.0+0x1abb/0x3e50 net/core/rtnetlink.c:3158
     rtnl_changelink net/core/rtnetlink.c:3776 [inline]
     __rtnl_newlink net/core/rtnetlink.c:3935 [inline]
     rtnl_newlink+0x11bd/0x2380 net/core/rtnetlink.c:4072
     rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958