INFO: task kworker/u4:14:12269 blocked for more than 143 seconds. Not tainted 5.14.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:14 state:D stack:23592 pid:12269 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common kernel/locking/mutex.c:669 [inline] __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729 ip6gre_exit_batch_net+0x88/0x760 net/ipv6/ip6_gre.c:1626 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:591 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task syz-executor.0:19569 blocked for more than 143 seconds. Not tainted 5.14.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:26600 pid:19569 ppid: 8444 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common kernel/locking/mutex.c:669 [inline] __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729 tun_detach drivers/net/tun.c:684 [inline] tun_chr_close+0x3a/0x180 drivers/net/tun.c:3397 __fput+0x288/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbae/0x2a30 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2868 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007f96b789b188 EFLAGS: 00000246 ORIG_RAX: 000000000000010f RAX: fffffffffffffdfe RBX: 000000000056bf80 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffc874559ef R14: 00007f96b789b300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1649: #0: ffffffff8b97d220 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/8334: #0: ffff88802a5fa5f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 3 locks held by kworker/0:7/10419: #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc900173b7db0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:251 2 locks held by kworker/0:9/10428: 4 locks held by kworker/u4:14/12269: #0: ffff888140275938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888140275938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888140275938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888140275938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888140275938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888140275938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90003087db0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0cea50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:553 #3: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x760 net/ipv6/ip6_gre.c:1626 1 lock held by syz-executor.0/19569: #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3397 1 lock held by syz-executor.5/25527: #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3397 3 locks held by kworker/0:19/25665: #0: ffff88802a788138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88802a788138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff88802a788138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff88802a788138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff88802a788138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff88802a788138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc900051efdb0 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4590 3 locks held by kworker/0:20/25666: #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c67d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc900051ffdb0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 1 lock held by syz-executor.3/28254: #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3397 1 lock held by syz-executor.4/28255: #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3397 2 locks held by syz-executor.1/28268: #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569 #1: ffffffff8b9865a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8b9865a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4fc/0x620 kernel/rcu/tree_exp.h:837 1 lock held by syz-executor.0/28311: #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d0e1ca8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1649 Comm: khungtaskd Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10428 Comm: kworker/0:9 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events iterate_cleanup_work RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0xc/0x12 Code: 56 57 41 50 41 51 41 52 41 53 e8 af 15 00 00 41 5b 41 5a 41 59 41 58 5f 5e 5a 59 c3 66 90 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <3c> 01 75 02 5a c3 56 0f b6 f0 e8 c5 ff ff ff 5e 5a c3 66 90 48 b8 RSP: 0018:ffffc90017417b90 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000012989 RCX: ffffffff815b0710 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8b667d00 RBP: ffffffff8b667d00 R08: 0000000000000000 R09: ffffffff8b667d03 R10: fffffbfff16ccfa0 R11: 0000000000000000 R12: ffffffff8b667d08 R13: ffffffff8b667d10 R14: 0000000000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff1e0787000 CR3: 000000000b68e000 CR4: 00000000001506f0 Call Trace: pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:590 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:56 [inline] do_raw_spin_unlock+0x171/0x230 kernel/locking/spinlock_debug.c:141 __raw_spin_unlock include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock+0x1a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:403 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2251 [inline] nf_ct_iterate_cleanup+0x144/0x450 net/netfilter/nf_conntrack_core.c:2275 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2363 [inline] nf_ct_iterate_cleanup_net+0x236/0x400 net/netfilter/nf_conntrack_core.c:2347 iterate_cleanup_work+0x45/0x130 net/netfilter/nf_nat_masquerade.c:216 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 56 push %rsi 1: 57 push %rdi 2: 41 50 push %r8 4: 41 51 push %r9 6: 41 52 push %r10 8: 41 53 push %r11 a: e8 af 15 00 00 callq 0x15be f: 41 5b pop %r11 11: 41 5a pop %r10 13: 41 59 pop %r9 15: 41 58 pop %r8 17: 5f pop %rdi 18: 5e pop %rsi 19: 5a pop %rdx 1a: 59 pop %rcx 1b: c3 retq 1c: 66 90 xchg %ax,%ax 1e: 52 push %rdx 1f: b8 01 00 00 00 mov $0x1,%eax 24: 31 d2 xor %edx,%edx 26: f0 0f b0 17 lock cmpxchg %dl,(%rdi) * 2a: 3c 01 cmp $0x1,%al <-- trapping instruction 2c: 75 02 jne 0x30 2e: 5a pop %rdx 2f: c3 retq 30: 56 push %rsi 31: 0f b6 f0 movzbl %al,%esi 34: e8 c5 ff ff ff callq 0xfffffffe 39: 5e pop %rsi 3a: 5a pop %rdx 3b: c3 retq 3c: 66 90 xchg %ax,%ax 3e: 48 rex.W 3f: b8 .byte 0xb8