syzbot

INFO: task syz-executor:4729 blocked for more than 143 seconds.
      Not tainted 5.15.173-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22272 pid: 4729 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039
 netdev_run_todo+0x381/0xc40 net/core/dev.c:10630
 ip_tunnel_delete_nets+0x2f2/0x330 net/ipv4/ip_tunnel.c:1152
 ops_exit_list net/core/net_namespace.c:177 [inline]
 setup_net+0x81c/0x9e0 net/core/net_namespace.c:355
 copy_net_ns+0x392/0x5d0 net/core/net_namespace.c:476
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x531/0xa40 kernel/fork.c:3099
 __do_sys_unshare kernel/fork.c:3173 [inline]
 __se_sys_unshare kernel/fork.c:3171 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3171
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff18cba1f17
RSP: 002b:00007ffce8c88278 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007ff18cd57f40 RCX: 00007ff18cba1f17
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007ff18cd58a38 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000000000000c
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/0:1/13: