INFO: task syz-executor.4:25878 can't die for more than 143 seconds.
task:syz-executor.4  state:R  running task     stack:27208 pid:25878 ppid: 23965 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4965 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6246
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6412
 __cond_resched+0x13/0x20 kernel/sched/core.c:8125
 _cond_resched include/linux/sched.h:2027 [inline]
 inet_twsk_purge+0xed/0x7d0 net/ipv4/inet_timewait_sock.c:267
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 setup_net+0x639/0xa30 net/core/net_namespace.c:349
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:470
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3125
 __do_sys_unshare kernel/fork.c:3196 [inline]
 __se_sys_unshare kernel/fork.c:3194 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3194
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f5f3b2fea39
RSP: 002b:00007f5f38853188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f5f3b402020 RCX: 00007f5f3b2fea39
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f5f3b358c5f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffe3612c4f R14: 00007f5f38853300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.1:25945 can't die for more than 146 seconds.
task:syz-executor.1  state:R  running task     stack:27864 pid:25945 ppid: 16297 flags:0x00004006
Call Trace:
 <TASK>
 </TASK>
INFO: task syz-executor.0:25958 can't die for more than 148 seconds.
task:syz-executor.0  state:R  running task     stack:27040 pid:25958 ppid: 14438 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4965 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6246
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6412
 __cond_resched+0x13/0x20 kernel/sched/core.c:8125
 rcu_lock_release include/linux/rcupdate.h:273 [inline]
 rcu_read_unlock include/linux/rcupdate.h:727 [inline]
 inet_twsk_purge+0x503/0x7d0 net/ipv4/inet_timewait_sock.c:299
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 setup_net+0x639/0xa30 net/core/net_namespace.c:349
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:470
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3125
 __do_sys_unshare kernel/fork.c:3196 [inline]
 __se_sys_unshare kernel/fork.c:3194 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3194
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f1dc1e00a39
RSP: 002b:00007f1dbf334188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f1dc1f040e0 RCX: 00007f1dc1e00a39
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f1dc1e5ac5f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff45719e4f R14: 00007f1dbf334300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.2:26027 can't die for more than 152 seconds.
task:syz-executor.2  state:R  running task     stack:26936 pid:26027 ppid: 16694 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4965 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6246
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6412
 __cond_resched+0x13/0x20 kernel/sched/core.c:8125
 _cond_resched include/linux/sched.h:2027 [inline]
 inet_twsk_purge+0xed/0x7d0 net/ipv4/inet_timewait_sock.c:267
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 setup_net+0x639/0xa30 net/core/net_namespace.c:349
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:470
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3125
 __do_sys_unshare kernel/fork.c:3196 [inline]
 __se_sys_unshare kernel/fork.c:3194 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3194
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f287d185a39
RSP: 002b:00007f287a6b9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f287d2890e0 RCX: 00007f287d185a39
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f287d1dfc5f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc99c7432f R14: 00007f287a6b9300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u4:1/10:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb835a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
1 lock held by in:imklog/6235:
1 lock held by syz-executor.4/25878:
2 locks held by syz-executor.1/25945:
1 lock held by syz-executor.0/25958:
1 lock held by syz-executor.2/26027:

=============================================