netlink: 16 bytes leftover after parsing attributes in process `syz-executor.5'.
netlink: 16 bytes leftover after parsing attributes in process `syz-executor.5'.
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
INFO: task syz-executor.3:902 blocked for more than 140 seconds.
      Not tainted 4.9.155+ #27
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D25768   902      1 0x00000004
 ffff8801a54fc740 ffff8801d759c200 ffff8801db721000 ffff8801c6eb0000
 ffff8801db721018 ffff8801a3aa7598 ffffffff82806806 f28d56b80fa1a972
 0000000000000001 ffff8801a54fcff0 0000000000000006 ffff8801db7218f0
Call Trace:
 [<ffffffff82807d92>] schedule+0x92/0x1c0 kernel/sched/core.c:3553
 [<ffffffff82808733>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff8280a68d>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8280a68d>] mutex_lock_nested+0x38d/0x920 kernel/locking/mutex.c:621
 [<ffffffff818928ad>] fuse_lock_inode+0xad/0xe0 fs/fuse/inode.c:364
 [<ffffffff81873bb9>] fuse_lookup+0x89/0x3b0 fs/fuse/dir.c:406
 [<ffffffff8152c99b>] lookup_slow+0x24b/0x480 fs/namei.c:1709
 [<ffffffff8153bc0e>] walk_component+0x71e/0xce0 fs/namei.c:1825
 [<ffffffff8153ca67>] link_path_walk+0x897/0x1200 fs/namei.c:2161
 [<ffffffff8153d977>] path_mountpoint+0x67/0x6d0 fs/namei.c:2737
 [<ffffffff81542502>] filename_mountpoint+0x2f2/0x350 fs/namei.c:2760
 [<ffffffff81543a8a>] user_path_mountpoint_at+0x3a/0x50 fs/namei.c:2788
 [<ffffffff81579bd6>] SYSC_umount fs/namespace.c:1722 [inline]
 [<ffffffff81579bd6>] SyS_umount+0x136/0xd30 fs/namespace.c:1706
 [<ffffffff810056bd>] do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285
 [<ffffffff82816a93>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131bbab>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131bbab>] watchdog+0x11b/0xa40 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813fea8f>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4336
2 locks held by rs:main Q:Reg/1893:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156f2f8>] __fdget_pos+0xa8/0xd0 fs/file.c:781
 #1:  (sb_writers#4){.+.+.+}, at: [<ffffffff8150cf79>] file_start_write include/linux/fs.h:2642 [inline]
 #1:  (sb_writers#4){.+.+.+}, at: [<ffffffff8150cf79>] vfs_write+0x3e9/0x520 fs/read_write.c:558
1 lock held by rsyslogd/1896:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156f2f8>] __fdget_pos+0xa8/0xd0 fs/file.c:781
2 locks held by getty/2023:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82814b83>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81d3982e>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.3/902:
 #0:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff8152c8b0>] inode_lock_shared include/linux/fs.h:778 [inline]
 #0:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff8152c8b0>] lookup_slow+0x160/0x480 fs/namei.c:1686
 #1:  (&fi->mutex){+.+.+.}, at: [<ffffffff818928ad>] fuse_lock_inode+0xad/0xe0 fs/fuse/inode.c:364
2 locks held by syz-executor.3/2031:
 #0:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff8152c8b0>] inode_lock_shared include/linux/fs.h:778 [inline]
 #0:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff8152c8b0>] lookup_slow+0x160/0x480 fs/namei.c:1686
 #1:  (&fi->mutex){+.+.+.}, at: [<ffffffff818928ad>] fuse_lock_inode+0xad/0xe0 fs/fuse/inode.c:364

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

NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.155+ #27
 ffff8801d9907cd0 ffffffff81b47871 0000000000000000 0000000000000000
 0000000000000000 ffffffff81097301 00000000003ffe91 ffff8801d9907d08
 ffffffff81b52afc 0000000000000000 0000000000000000 0000000000000000
Call Trace:
 [<ffffffff81b47871>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b47871>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff81b52afc>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81b52a84>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60
 [<ffffffff81097494>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8131c087>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8131c087>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8131c087>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8131c087>] watchdog+0x5f7/0xa40 kernel/hung_task.c:239
 [<ffffffff81142028>] kthread+0x278/0x310 kernel/kthread.c:211
 [<ffffffff82816c5c>] 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 0xffffffff82815692