audit: type=1400 audit(1521895388.863:32913): avc:  denied  { net_admin } for  pid=13798 comm="ip" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
INFO: task syz-executor3:13713 blocked for more than 120 seconds.
      Not tainted 4.9.89-ge34e318 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D26656 13713   9977 0x20020006
 ffff8801c1b39800 0000000000000000 ffff8801b61d8fc0 ffffffff84429880
 ffff8801db221b98 ffff8801cf2df370 ffffffff838a4c0b 0000000041b58ab3
 ffffffff84193da8 00ffffff81239af0 ffff8801db222468 ffff8801db222490
Call Trace:
 [<ffffffff838a61af>] schedule+0x7f/0x1b0 kernel/sched/core.c:3551
 [<ffffffff838b216c>] schedule_timeout+0x56c/0x10b0 kernel/time/timer.c:1768
 [<ffffffff838a43be>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:5173
 [<ffffffff838a7629>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff838a7629>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff838a6d07>] __wait_on_bit+0x57/0x120 kernel/sched/wait.c:383
 [<ffffffff81430204>] wait_on_page_bit+0xf4/0x140 mm/filemap.c:802
 [<ffffffff81430411>] wait_on_page_writeback include/linux/pagemap.h:526 [inline]
 [<ffffffff81430411>] __filemap_fdatawait_range+0x1c1/0x2b0 mm/filemap.c:453
 [<ffffffff81430525>] filemap_fdatawait_range+0x25/0x50 mm/filemap.c:483
 [<ffffffff81439155>] filemap_fdatawait mm/filemap.c:533 [inline]
 [<ffffffff81439155>] filemap_write_and_wait+0xf5/0x120 mm/filemap.c:551
 [<ffffffff8162b660>] __sync_blockdev fs/block_dev.c:194 [inline]
 [<ffffffff8162b660>] sync_blockdev.part.28+0x50/0x70 fs/block_dev.c:203
 [<ffffffff8162bc84>] sync_blockdev fs/block_dev.c:190 [inline]
 [<ffffffff8162bc84>] __blkdev_put+0x184/0x7e0 fs/block_dev.c:1585
 [<ffffffff8162d0b5>] blkdev_put+0x85/0x550 fs/block_dev.c:1663
 [<ffffffff8162d60b>] blkdev_close+0x8b/0xb0 fs/block_dev.c:1670
 [<ffffffff8157366c>] __fput+0x28c/0x6e0 fs/file_table.c:208
 [<ffffffff81573b45>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff81195fe5>] task_work_run+0x115/0x190 kernel/task_work.c:116
 [<ffffffff8113c997>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff8113c997>] do_exit+0x7e7/0x2a40 kernel/exit.c:833
 [<ffffffff811430a8>] do_group_exit+0x108/0x320 kernel/exit.c:937
 [<ffffffff81165f24>] get_signal+0x4d4/0x14e0 kernel/signal.c:2317
 [<ffffffff81052c87>] do_signal+0x87/0x19f0 arch/x86/kernel/signal.c:807
 [<ffffffff81004ff1>] exit_to_usermode_loop+0xe1/0x120 arch/x86/entry/common.c:157
 [<ffffffff81007261>] prepare_exit_to_usermode arch/x86/entry/common.c:191 [inline]
 [<ffffffff81007261>] syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 [<ffffffff81007261>] do_syscall_32_irqs_on arch/x86/entry/common.c:331 [inline]
 [<ffffffff81007261>] do_fast_syscall_32+0x5c1/0x870 arch/x86/entry/common.c:387
 [<ffffffff838b7210>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

Showing all locks held in the system:
2 locks held by khungtaskd/515:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81370ca5>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81370ca5>] watchdog+0x125/0xa70 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81235c50>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336
2 locks held by getty/3785:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838b3ce2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82008bc4>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133
3 locks held by kworker/u4:12/9065:
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189f42>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189f42>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189f42>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189f42>] process_one_work+0x6f2/0x1610 kernel/workqueue.c:2085
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff81189f7c>] process_one_work+0x72c/0x1610 kernel/workqueue.c:2089
 #2:  (&type->s_umount_key#22){.+.+..}, at: [<ffffffff81577b80>] trylock_super+0x20/0x100 fs/super.c:393
1 lock held by syz-executor3/13713:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162bbbc>] __blkdev_put+0xbc/0x7e0 fs/block_dev.c:1579
1 lock held by blkid/13782:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162c3ec>] __blkdev_get+0x10c/0xd50 fs/block_dev.c:1268
1 lock held by syz-executor3/13950:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162c3ec>] __blkdev_get+0x10c/0xd50 fs/block_dev.c:1268

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

NMI backtrace for cpu 0
CPU: 0 PID: 515 Comm: khungtaskd Not tainted 4.9.89-ge34e318 #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8777d00 ffffffff81d93609 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810bb690 ffff8801d8777d38
 ffffffff81d9e72d 0000000000000000 0000000000000000 ffff8801cf4fcc18
Call Trace:
 [<ffffffff81d93609>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d93609>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81d9e72d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99
 [<ffffffff81d9e867>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60
 [<ffffffff810bb784>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81371270>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81371270>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81371270>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81371270>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239
 [<ffffffff8119af4d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838b5c9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff838b4756