unregister_netdevice: waiting for syz_tun to become free. Usage count = 4
ref_tracker: netdev@ffff88807cbe8618 has 1/3 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
     netdev_hold include/linux/netdevice.h:4429 [inline]
     dst_init+0xd9/0x480 net/core/dst.c:52
     dst_alloc+0x12a/0x170 net/core/dst.c:94
     ip6_dst_alloc net/ipv6/route.c:342 [inline]
     ip6_rt_cache_alloc+0x3c3/0xa40 net/ipv6/route.c:1380
     rt6_do_redirect+0xc28/0x10c0 net/ipv6/route.c:4332
     ip6_redirect_no_header+0x2be/0x3a0 net/ipv6/route.c:3238
     ndisc_redirect_rcv+0x519/0x920 net/ipv6/ndisc.c:1625
     icmpv6_rcv+0x1340/0x1cc0 net/ipv6/icmp.c:1187
     ip6_protocol_deliver_rcu+0xe2d/0x1600 net/ipv6/ip6_input.c:438
     ip6_input_finish+0x191/0x370 net/ipv6/ip6_input.c:489
     NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
     ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:500
     ip6_mc_input+0x655/0xbd0 net/ipv6/ip6_input.c:590
     NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
     __netif_receive_skb_one_core net/core/dev.c:6152 [inline]
     __netif_receive_skb net/core/dev.c:6265 [inline]
     netif_receive_skb_internal net/core/dev.c:6351 [inline]
     netif_receive_skb+0x278/0xbb0 net/core/dev.c:6410
     tun_rx_batched+0x1de/0x790 drivers/net/tun.c:1485
     tun_get_user+0x2a78/0x3dd0 drivers/net/tun.c:1953

ref_tracker: netdev@ffff88807cbe8618 has 1/3 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
     netdev_tracker_alloc include/linux/netdevice.h:4412 [inline]
     netdev_get_by_index+0x79/0xb0 net/core/dev.c:1021
     fib6_nh_init+0x1f7/0x2060 net/ipv6/route.c:3601
     ip6_route_info_create_nh+0x16a/0xad0 net/ipv6/route.c:3901
     ip6_route_add+0x6e/0x1b0 net/ipv6/route.c:3953
     rt6_add_route_info+0x326/0x3f0 net/ipv6/route.c:4427
     rt6_route_rcv+0x465/0x810 net/ipv6/route.c:1024
     ndisc_router_discovery+0x1471/0x40a0 net/ipv6/ndisc.c:1523
     icmpv6_rcv+0x1340/0x1cc0 net/ipv6/icmp.c:1187
     ip6_protocol_deliver_rcu+0xe2d/0x1600 net/ipv6/ip6_input.c:438
     ip6_input_finish+0x191/0x370 net/ipv6/ip6_input.c:489
     NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
     ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:500
     ip6_mc_input+0x655/0xbd0 net/ipv6/ip6_input.c:590
     NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
     __netif_receive_skb_one_core net/core/dev.c:6152 [inline]
     __netif_receive_skb net/core/dev.c:6265 [inline]
     netif_receive_skb_internal net/core/dev.c:6351 [inline]
     netif_receive_skb+0x278/0xbb0 net/core/dev.c:6410
     tun_rx_batched+0x1de/0x790 drivers/net/tun.c:1485

ref_tracker: netdev@ffff88807cbe8618 has 1/3 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
     netdev_hold include/linux/netdevice.h:4429 [inline]
     ipv6_add_dev+0x50f/0x13a0 net/ipv6/addrconf.c:411
     addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3650
     notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
     call_netdevice_notifiers_extack net/core/dev.c:2281 [inline]
     call_netdevice_notifiers net/core/dev.c:2295 [inline]
     register_netdevice+0x171a/0x1cd0 net/core/dev.c:11444
     tun_set_iff+0x844/0xf00 drivers/net/tun.c:2807
     __tun_chr_ioctl+0x7bb/0x1e10 drivers/net/tun.c:3088
     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:63 [inline]
     do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
     entry_SYSCALL_64_after_hwframe+0x77/0x7f