netdevsim netdevsim4 netdevsim3 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim4 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim4 netdevsim3 (unregistering): unset [1, 1] type 2 family 0 port 256 - 0
netdevsim netdevsim4 netdevsim3 (unregistering): unset [1, 2] type 2 family 0 port 19999 - 0
------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff888026f0a400 object type: work_struct hint: udp_tunnel_nic_device_sync_work+0x0/0xa50 net/ipv4/udp_tunnel_nic.c:-1
WARNING: CPU: 1 PID: 17522 at lib/debugobjects.c:615 debug_print_object+0x16b/0x1e0 lib/debugobjects.c:612
Modules linked in:
CPU: 1 UID: 0 PID: 17522 Comm: syz.4.3329 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:debug_print_object+0x16b/0x1e0 lib/debugobjects.c:612
Code: 4c 89 ff e8 87 9e 8d fd 4d 8b 0f 48 c7 c7 00 45 c0 8b 48 8b 34 24 4c 89 ea 89 e9 4d 89 f0 41 54 e8 0a 11 ec fc 48 83 c4 08 90 <0f> 0b 90 90 ff 05 67 57 07 0b 48 83 c4 08 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc900040eebd8 EFLAGS: 00010286
RAX: 5bef5500d6a4f800 RBX: dffffc0000000000 RCX: ffff88801c373c80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfa138 R12: ffffffff89d9f1b0
R13: ffffffff8bc04680 R14: ffff888026f0a400 R15: ffffffff8b69cc00
FS:  00007fb5093f66c0(0000) GS:ffff888125e3b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000514e2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline]
 debug_check_no_obj_freed+0x3a2/0x470 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4695 [inline]
 kfree+0x112/0x440 mm/slub.c:4894
 udp_tunnel_nic_free net/ipv4/udp_tunnel_nic.c:785 [inline]
 udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:910 [inline]
 udp_tunnel_nic_netdevice_event+0x11ab/0x1810 net/ipv4/udp_tunnel_nic.c:942
 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 unregister_netdevice_many_notify+0x14d7/0x1ff0 net/core/dev.c:12254
 unregister_netdevice_many net/core/dev.c:12317 [inline]
 unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:12161
 unregister_netdevice include/linux/netdevice.h:3389 [inline]
 nsim_destroy+0x1dd/0x670 drivers/net/netdevsim/netdev.c:1171
 __nsim_dev_port_del+0x14d/0x1b0 drivers/net/netdevsim/dev.c:1473
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1485 [inline]
 nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1707
 nsim_dev_reload_down+0x8a/0xc0 drivers/net/netdevsim/dev.c:983
 devlink_reload+0x1b6/0x8d0 net/devlink/dev.c:461
 devlink_nl_reload_doit+0xb35/0xd50 net/devlink/dev.c:584
 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 ____sys_sendmsg+0x505/0x830 net/socket.c:2630
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684
 __sys_sendmsg net/socket.c:2716 [inline]
 __do_sys_sendmsg net/socket.c:2721 [inline]
 __se_sys_sendmsg net/socket.c:2719 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb50b18eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb5093f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb50b3e6090 RCX: 00007fb50b18eec9
RDX: 0000000000008000 RSI: 0000200000000080 RDI: 0000000000000004
RBP: 00007fb50b211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb50b3e6128 R14: 00007fb50b3e6090 R15: 00007ffda1338978
 </TASK>