INFO: task syz-executor.2:24449 blocked for more than 143 seconds. Not tainted 5.11.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:27944 pid:24449 ppid: 17687 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4313 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5064 schedule+0xcf/0x270 kernel/sched/core.c:5143 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1868 bcm_release+0x94/0x750 net/can/bcm.c:1472 __sock_release+0xcd/0x280 net/socket.c:597 sock_close+0x18/0x20 net/socket.c:1256 __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+0xc5c/0x2ae0 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x3e9/0x20a0 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: 0033:0x45e219 RSP: 002b:00007fa4043c1c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000003 RBX: 0000000000000003 RCX: 000000000045e219 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffe25c44edf R14: 00007fa4043c29c0 R15: 000000000119bf8c Showing all locks held in the system: 3 locks held by kworker/u4:2/30: 3 locks held by kworker/u4:3/106: #0: ffff8880b9f34c58 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1319 [inline] #0: ffff8880b9f34c58 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x217/0x21a0 kernel/sched/core.c:4981 #1: ffff8880b9f20088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833 #2: ffff8880b9f24898 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5a/0x1f0 kernel/time/timer.c:944 1 lock held by khungtaskd/1650: #0: ffffffff8b373920 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8170: #0: ffff88801c0c45f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 2 locks held by syz-executor.2/24449: #0: ffff888028f0e6d0 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff888028f0e6d0 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:596 #1: ffffffff8ca455d0 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1868 1 lock held by syz-executor.1/25139: #0: ffffffff8ca455d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:479 1 lock held by syz-executor.5/25141: #0: ffffffff8ca455d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:479 1 lock held by syz-executor.2/25142: #0: ffffffff8ca455d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:479 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1650 Comm: khungtaskd Not tainted 5.11.0-rc4-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: 30 Comm: kworker/u4:2 Not tainted 5.11.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:task_wait_context kernel/locking/lockdep.c:4446 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4527 [inline] RIP: 0010:__lock_acquire+0x5ea/0x54f0 kernel/locking/lockdep.c:4782 Code: 01 65 8b 05 f0 93 a9 7e 85 c0 0f 85 9f 0a 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 38 48 89 ca 48 c1 ea 03 0f b6 14 02 <48> 89 c8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 5b 3c 00 00 8b RSP: 0018:ffffc90000e4f958 EFLAGS: 00000017 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffff88801103896c RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000001 RBP: ffff888011038000 R08: 0000000000000000 R09: ffffffff8ed3181f R10: fffffbfff1da6303 R11: 0000000000000000 R12: ffff888011038a00 R13: ffff888011038981 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbbbbe99d68 CR3: 0000000021597000 CR4: 0000000000350ee0 Call Trace: lock_acquire kernel/locking/lockdep.c:5437 [inline] lock_acquire+0x29d/0x740 kernel/locking/lockdep.c:5402 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] nf_conntrack_lock net/netfilter/nf_conntrack_core.c:91 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2199 [inline] nf_ct_iterate_cleanup+0x183/0x400 net/netfilter/nf_conntrack_core.c:2244 nf_conntrack_cleanup_net_list+0x81/0x250 net/netfilter/nf_conntrack_core.c:2431 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:190 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604 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