netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2492 netlink_unicast_kernel net/netlink/af_netlink.c:1315 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1341 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 981 at lib/ref_tracker.c:38 spin_unlock_irqrestore include/linux/spinlock.h:409 [inline] WARNING: CPU: 1 PID: 981 at lib/ref_tracker.c:38 ref_tracker_dir_exit.cold+0x137/0x1e3 lib/ref_tracker.c:37 Modules linked in: CPU: 1 PID: 981 Comm: kworker/u4:5 Not tainted 5.16.0-rc6-next-20211223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:ref_tracker_dir_exit.cold+0x137/0x1e3 lib/ref_tracker.c:38 Code: 4c 89 ef e8 81 96 9f f8 4c 8b 3c 24 4c 39 fd 49 8b 07 0f 85 b5 00 00 00 e8 9c 7d 54 f8 48 8b 74 24 10 4c 89 e7 e8 3f 4c 36 00 <0f> 0b e9 3b f0 e7 fa 4c 89 ff e8 50 96 9f f8 e9 d4 fe ff ff e8 36 RSP: 0018:ffffc90004b87978 EFLAGS: 00010246 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffff88807c4c4600 R08: 0000000000000001 R09: ffffffff8ffb594f R10: 0000000000000001 R11: 0000000000088077 R12: ffff88807c4c45b8 R13: ffff88807c4c4600 R14: ffff88807c4c4600 R15: ffff88807c4c4600 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8faa858950 CR3: 000000000b88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: free_netdev+0x32a/0x5b0 net/core/dev.c:10280 netdev_run_todo+0x8a0/0xaa0 net/core/dev.c:9957 default_device_exit_batch+0x2ff/0x3c0 net/core/dev.c:10938 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:595 process_one_work+0x9ac/0x1680 kernel/workqueue.c:2307 worker_thread+0x652/0x11c0 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:381 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295