INFO: task kworker/0:9:11349 blocked for more than 147 seconds. Not tainted 5.10.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:9 state:D stack:26432 pid:11349 ppid: 2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5216 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x81a/0x1110 kernel/locking/mutex.c:1103 addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4569 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 INFO: task kworker/1:9:11419 blocked for more than 148 seconds. Not tainted 5.10.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:9 state:D stack:24736 pid:11419 ppid: 2 flags:0x00004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5216 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x81a/0x1110 kernel/locking/mutex.c:1103 linkwatch_event+0xb/0x60 net/core/link_watch.c:250 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Showing all locks held in the system: 1 lock held by khungtaskd/1643: #0: ffffffff8b3637e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8169: #0: ffff88801b396870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:949 3 locks held by kworker/0:9/11349: #0: ffff888021419138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888021419138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888021419138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888021419138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888021419138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888021419138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc9001642fda8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 #2: ffffffff8c942c28 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4569 3 locks held by kworker/1:9/11419: #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc90001b5fda8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 #2: ffffffff8c942c28 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250 3 locks held by syz-executor.2/28237: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1643 Comm: khungtaskd Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd43/0xfa0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 28237 Comm: syz-executor.2 Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_preemption_disabled+0x9/0x150 lib/smp_processor_id.c:13 Code: 04 31 ff 89 de 0f 1f 44 00 00 85 db 75 ae 0f 1f 44 00 00 41 bc 01 00 00 00 e8 f3 ee cd fa eb 9f cc 41 56 41 55 49 89 f5 41 54 <55> 48 89 fd 53 0f 1f 44 00 00 65 44 8b 25 b5 69 16 77 65 8b 1d 0e RSP: 0018:ffffc90000d90b08 EFLAGS: 00000006 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000100 RDX: ffff8880708e3780 RSI: ffffffff899e56c0 RDI: ffffffff899e5700 RBP: ffff888029d2c160 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81628a22 R11: 0000000000000000 R12: 0000000000000001 R13: ffffffff899e56c0 R14: 0000000000000001 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f002a7f6000 CR3: 00000000137a7000 CR4: 0000000000350ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:319 [inline] rcu_is_watching+0xe/0xc0 kernel/rcu/tree.c:1113 rcu_read_lock_held_common kernel/rcu/update.c:106 [inline] rcu_read_lock_sched_held+0x1c/0x70 kernel/rcu/update.c:121 trace_hrtimer_expire_exit include/trace/events/timer.h:279 [inline] __run_hrtimer kernel/time/hrtimer.c:1522 [inline] __hrtimer_run_queues+0xc46/0xea0 kernel/time/hrtimer.c:1583 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1102 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline] sysvec_apic_timer_interrupt+0x48/0x100 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:199 Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 ce 09 6b f8 48 89 ef e8 56 be 6b f8 e8 f1 c1 8a f8 fb bf 01 00 00 00 e6 c5 5f f8 65 8b 05 9f 6c 14 77 85 c0 74 02 5d c3 e8 db c1 12 RSP: 0018:ffffc90000d90e18 EFLAGS: 00000206 RAX: 0000000002b910fa RBX: ffffffffffffff77 RCX: ffffffff81581107 RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000001 RBP: ffff8880b9f25940 R08: 0000000000000001 R09: ffffffff8ebd57bf R10: fffffbfff1d7aaf7 R11: 0000000000000001 R12: ffffc90000d90ea8 R13: 0000000000200000 R14: dffffc0000000000 R15: ffff8880b9f25940 __run_timers.part.0+0x396/0xa50 kernel/time/timer.c:1733 __run_timers kernel/time/timer.c:1712 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1746 __do_softirq+0x2a5/0x9f7 kernel/softirq.c:343 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:226 [inline] __irq_exit_rcu kernel/softirq.c:420 [inline] irq_exit_rcu+0x134/0x200 kernel/softirq.c:432 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628 RIP: 0010:__local_bh_enable_ip+0xa4/0x110 kernel/softirq.c:203 Code: e8 51 fd 08 00 65 8b 05 0a a4 bd 7e a9 00 ff ff 00 74 45 bf 01 00 00 00 e8 39 fd 08 00 e8 34 f9 33 00 fb 65 8b 05 ec a3 bd 7e <85> c0 74 4a 5b 5d c3 65 8b 05 5a b2 bd 7e 85 c0 75 a6 0f 0b eb a2 RSP: 0018:ffffc90002b2f5f8 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000200 RCX: ffffffff81581107 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff873232b8 R08: 0000000000000001 R09: ffffffff8ebd57bf R10: fffffbfff1d7aaf7 R11: 0000000000000001 R12: ffffffff8b069680 R13: 000000000000cd30 R14: 0000000000000000 R15: 0000000000000001 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2221 [inline] nf_ct_iterate_cleanup+0x11f/0x400 net/netfilter/nf_conntrack_core.c:2244 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2329 [inline] nf_ct_iterate_cleanup_net+0x113/0x170 net/netfilter/nf_conntrack_core.c:2314 masq_device_event+0xae/0xe0 net/netfilter/nf_nat_masquerade.c:88 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2040 call_netdevice_notifiers_extack net/core/dev.c:2052 [inline] call_netdevice_notifiers net/core/dev.c:2066 [inline] dev_close_many+0x30b/0x650 net/core/dev.c:1641 rollback_registered_many+0x3ee/0x14c0 net/core/dev.c:9472 rollback_registered net/core/dev.c:9540 [inline] unregister_netdevice_queue+0x2dd/0x570 net/core/dev.c:10700 unregister_netdevice include/linux/netdevice.h:2868 [inline] __tun_detach+0x105a/0x13d0 drivers/net/tun.c:662 tun_detach drivers/net/tun.c:679 [inline] tun_chr_close+0xd9/0x180 drivers/net/tun.c:3354 __fput+0x283/0x920 fs/file_table.c:280 task_work_run+0xdd/0x190 kernel/task_work.c:140 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xb89/0x29e0 kernel/exit.c:823 do_group_exit+0x125/0x310 kernel/exit.c:920 get_signal+0x3ec/0x2010 kernel/signal.c:2770 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e229 Code: Unable to access opcode bytes at RIP 0x45e1ff. RSP: 002b:00007f2f92fbac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000048 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 000000000045e229 RDX: 0000000000042000 RSI: 0000000000000004 RDI: 0000000000000003 RBP: 000000000119c068 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffceed9db8f R14: 00007f2f92fbb9c0 R15: 000000000119c034