[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.54' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 857.971577] INFO: task syz-executor224:7973 blocked for more than 140 seconds. [ 857.979104] Not tainted 4.14.271-syzkaller #0 [ 857.985602] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 857.993975] syz-executor224 D28176 7973 7971 0x00000004 [ 857.999593] Call Trace: [ 858.002748] __schedule+0x88b/0x1de0 [ 858.006450] ? lock_acquire+0x170/0x3f0 [ 858.010431] ? io_schedule_timeout+0x140/0x140 [ 858.015744] ? _raw_spin_unlock+0x29/0x40 [ 858.019884] ? fuse_writepage_locked+0xe80/0xe80 [ 858.025275] schedule+0x8d/0x1b0 [ 858.028631] fuse_wait_on_page_writeback.isra.0+0xdc/0x120 [ 858.034801] ? fuse_do_ioctl+0x1570/0x1570 [ 858.039037] ? end_page_writeback+0xe3/0x1c0 [ 858.044001] ? wait_woken+0x230/0x230 [ 858.047792] fuse_launder_page+0xa2/0xd0 [ 858.052399] invalidate_inode_pages2_range+0x547/0xc00 [ 858.057691] ? clear_shadow_entry+0x160/0x160 [ 858.062705] ? fuse_range_is_writeback+0x1f0/0x1f0 [ 858.067637] ? fuse_file_alloc+0x1ca/0x260 [ 858.072411] ? _raw_spin_unlock+0x29/0x40 [ 858.076547] ? fuse_do_open+0x18e/0x460 [ 858.080515] fuse_finish_open+0x262/0x500 [ 858.085386] fuse_open_common+0x234/0x290 [ 858.089522] do_dentry_open+0x44b/0xec0 [ 858.094048] ? fuse_open_common+0x290/0x290 [ 858.098355] ? __inode_permission+0xcd/0x2f0 [ 858.103291] vfs_open+0x105/0x220 [ 858.106734] path_openat+0x628/0x2970 [ 858.110514] ? path_lookupat+0x780/0x780 [ 858.115589] ? trace_hardirqs_on+0x10/0x10 [ 858.119819] do_filp_open+0x179/0x3c0 [ 858.124173] ? may_open_dev+0xe0/0xe0 [ 858.127965] ? lock_downgrade+0x740/0x740 [ 858.132791] ? do_raw_spin_unlock+0x164/0x220 [ 858.137266] ? _raw_spin_unlock+0x29/0x40 [ 858.141929] ? __alloc_fd+0x1be/0x490 [ 858.145751] do_sys_open+0x296/0x410 [ 858.149447] ? filp_open+0x60/0x60 [ 858.153017] ? do_syscall_64+0x4c/0x640 [ 858.156985] ? compat_SyS_openat+0x30/0x30 [ 858.161198] do_syscall_64+0x1d5/0x640 [ 858.165158] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 858.170335] RIP: 0033:0x7f90a070a4c9 [ 858.174073] RSP: 002b:00007f90a06bb2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 [ 858.181844] RAX: ffffffffffffffda RBX: 00007f90a079b4c0 RCX: 00007f90a070a4c9 [ 858.189099] RDX: 00007f90a070a4c9 RSI: 0000000000000000 RDI: 00000000200001c0 [ 858.196388] RBP: 00007f90a0768164 R08: 0000000000000000 R09: 0000000000000000 [ 858.203724] R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e [ 858.210979] R13: 00007f90a0764158 R14: 00007f90a0766160 R15: 00007f90a079b4c8 [ 858.218299] [ 858.218299] Showing all locks held in the system: [ 858.224670] 1 lock held by khungtaskd/1523: [ 858.229014] #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a [ 858.238106] 2 locks held by syz-executor224/7973: [ 858.242992] #0: (sb_writers#10){.+.+}, at: [] mnt_want_write+0x3a/0xb0 [ 858.251453] #1: (&sb->s_type->i_mutex_key#17){+.+.}, at: [] fuse_open_common+0x1a4/0x290 [ 858.261497] [ 858.263110] ============================================= [ 858.263110] [ 858.270104] NMI backtrace for cpu 0 [ 858.273769] CPU: 0 PID: 1523 Comm: khungtaskd Not tainted 4.14.271-syzkaller #0 [ 858.281201] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 858.290531] Call Trace: [ 858.293114] dump_stack+0x1b2/0x281 [ 858.296733] nmi_cpu_backtrace.cold+0x57/0x93 [ 858.301204] ? irq_force_complete_move+0x350/0x350 [ 858.306114] nmi_trigger_cpumask_backtrace+0x13a/0x180 [ 858.311373] watchdog+0x5b9/0xb40 [ 858.314810] ? hungtask_pm_notify+0x50/0x50 [ 858.319108] kthread+0x30d/0x420 [ 858.322450] ? kthread_create_on_node+0xd0/0xd0 [ 858.327120] ret_from_fork+0x24/0x30 [ 858.330892] Sending NMI from CPU 0 to CPUs 1: [ 858.335481] NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff87242a1e [ 858.336447] Kernel panic - not syncing: hung_task: blocked tasks [ 858.348819] CPU: 0 PID: 1523 Comm: khungtaskd Not tainted 4.14.271-syzkaller #0 [ 858.356262] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 858.365590] Call Trace: [ 858.368166] dump_stack+0x1b2/0x281 [ 858.371776] panic+0x1f9/0x42d [ 858.374951] ? add_taint.cold+0x16/0x16 [ 858.378908] watchdog+0x5ca/0xb40 [ 858.382341] ? hungtask_pm_notify+0x50/0x50 [ 858.386641] kthread+0x30d/0x420 [ 858.389981] ? kthread_create_on_node+0xd0/0xd0 [ 858.394626] ret_from_fork+0x24/0x30 [ 858.398611] Kernel Offset: disabled [ 858.402225] Rebooting in 86400 seconds..