INFO: task syz-executor.3:13714 can't die for more than 143 seconds.
task:syz-executor.3  state:D stack:27112 pid:13714 ppid:  6550 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4955 [inline]
 __schedule+0x940/0x26f0 kernel/sched/core.c:6236
 schedule+0xd3/0x270 kernel/sched/core.c:6315
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6374
 __mutex_lock_common kernel/locking/mutex.c:672 [inline]
 __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:732
 tc_action_net_exit include/net/act_api.h:155 [inline]
 gate_exit_net+0x22/0x370 net/sched/act_gate.c:624
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 setup_net+0x639/0xa30 net/core/net_namespace.c:349
 copy_net_ns+0x319/0x760 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:3128
 __do_sys_unshare kernel/fork.c:3199 [inline]
 __se_sys_unshare kernel/fork.c:3197 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3197
 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: 0033:0x7f93ae531739
RSP: 002b:00007f93abaa8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f93ae635f80 RCX: 00007f93ae531739
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f93ae58bcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f93ae635f80
R13: 00007fff38befd0f R14: 00007f93abaa8300 R15: 0000000000022000

Showing all locks held in the system:
3 locks held by kworker/1:0/20:
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc90000da7db0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa3/0x1340 net/ipv6/addrconf.c:4047
1 lock held by khungtaskd/27:
 #0: ffffffff8b980960 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
4 locks held by kworker/u4:3/158:
 #0: ffff888144393138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888144393138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888144393138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888144393138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888144393138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888144393138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc90001bffdb0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffffffff8d0d1290 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:555
 #3: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: tc_action_net_exit include/net/act_api.h:155 [inline]
 #3: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: gate_exit_net+0x22/0x370 net/sched/act_gate.c:624
1 lock held by in:imklog/6230:
 #0: ffff88801defaaf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
2 locks held by agetty/6460:
 #0: ffff88802596a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
 #1: ffffc9000124c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113
3 locks held by kworker/1:3/15797:
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc90005d9fdb0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:251
3 locks held by kworker/0:7/12484:
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff8880258bb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc9000349fdb0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa3/0x1340 net/ipv6/addrconf.c:4047
2 locks held by kworker/0:8/12485:
3 locks held by kworker/0:10/12487:
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc9000350fdb0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
2 locks held by syz-executor.3/13714:
 #0: ffffffff8d0d1290 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:466
 #1: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: tc_action_net_exit include/net/act_api.h:155 [inline]
 #1: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: gate_exit_net+0x22/0x370 net/sched/act_gate.c:624
1 lock held by syz-executor.5/13838:
 #0: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569
2 locks held by syz-executor.2/14507:
 #0: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d0e4828 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569
 #1: ffffffff8b989ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8b989ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4fc/0x620 kernel/rcu/tree_exp.h:836

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