unregister_netdevice: waiting for syz_tun to become free. Usage count = 2
leaked reference.
 __netdev_tracker_alloc include/linux/netdevice.h:4070 [inline]
 netdev_tracker_alloc include/linux/netdevice.h:4082 [inline]
 fib_create_info+0x333c/0x4c00 net/ipv4/fib_semantics.c:1547
 fib_table_insert+0x199/0x1be0 net/ipv4/fib_trie.c:1236
 fib_magic+0x493/0x580 net/ipv4/fib_frontend.c:1104
 fib_add_ifaddr+0x16f/0x560 net/ipv4/fib_frontend.c:1126
 fib_inetaddr_event+0x166/0x2a0 net/ipv4/fib_frontend.c:1440
 notifier_call_chain+0xb6/0x3c0 kernel/notifier.c:93
 blocking_notifier_call_chain kernel/notifier.c:388 [inline]
 blocking_notifier_call_chain+0x6b/0xa0 kernel/notifier.c:376
 __inet_insert_ifa+0x955/0xc10 net/ipv4/devinet.c:555
 inet_rtm_newaddr+0x579/0xa40 net/ipv4/devinet.c:961
 rtnetlink_rcv_msg+0x43d/0xd50 net/core/rtnetlink.c:6395
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2546
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1913
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:747
 __sys_sendto+0x23a/0x340 net/socket.c:2144
 __do_sys_sendto net/socket.c:2156 [inline]
 __se_sys_sendto net/socket.c:2152 [inline]
 __x64_sys_sendto+0xe1/0x1b0 net/socket.c:2152