[ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Started System Logging Service. [ OK ] Started OpenBSD Secure Shell server. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.88' (ECDSA) to the list of known hosts. syzkaller login: [ 716.164361][ T1653] INFO: task syz-executor827:8500 can't die for more than 143 seconds. [ 716.172830][ T1653] task:syz-executor827 state:R running task stack:27176 pid: 8500 ppid: 8495 flags:0x00004006 [ 716.185978][ T1653] Call Trace: [ 716.189284][ T1653] ? iget5_locked+0xac/0x2d0 [ 716.193910][ T1653] ? lock_release+0x710/0x710 [ 716.200084][ T1653] ? rwlock_bug.part.0+0x90/0x90 [ 716.206208][ T1653] ? iget5_locked+0xcc/0x2d0 [ 716.210820][ T1653] ? _raw_spin_lock+0x2a/0x40 [ 716.216735][ T1653] ? fuse_init_file_inode+0x1e0/0x1e0 [ 716.222130][ T1653] ? _atomic_dec_and_lock+0x92/0x100 [ 716.228729][ T1653] ? iget5_locked+0xac/0x2d0 [ 716.233340][ T1653] ? fuse_inode_eq+0x80/0x80 [ 716.239007][ T1653] ? fuse_iget+0x271/0x610 [ 716.243443][ T1653] ? fuse_change_attributes+0x610/0x610 [ 716.250205][ T1653] ? fuse_simple_request+0x3e8/0xd90 [ 716.257260][ T1653] ? fuse_lookup_name+0x447/0x630 [ 716.262311][ T1653] ? fuse_create+0x30/0x30 [ 716.267777][ T1653] ? find_held_lock+0x2d/0x110 [ 716.272590][ T1653] ? mark_held_locks+0x9f/0xe0 [ 716.278543][ T1653] ? fuse_lookup.part.0+0xdf/0x390 [ 716.283692][ T1653] ? d_alloc_parallel+0x938/0x1ae0 [ 716.290039][ T1653] ? fuse_lookup_name+0x630/0x630 [ 716.295953][ T1653] ? lock_downgrade+0x6d0/0x6d0 [ 716.300836][ T1653] ? __d_lookup+0x477/0x760 [ 716.306699][ T1653] ? fuse_atomic_open+0x2de/0x440 [ 716.311739][ T1653] ? fuse_lookup+0x90/0x90 [ 716.317452][ T1653] ? lookup_open.isra.0+0xc3d/0x13d0 [ 716.322765][ T1653] ? vfs_unlink+0x600/0x600 [ 716.328417][ T1653] ? path_openat+0x9af/0x27a0 [ 716.333174][ T1653] ? path_lookupat+0x830/0x830 [ 716.339228][ T1653] ? lockdep_hardirqs_on_prepare+0x420/0x420 [ 716.345956][ T1653] ? do_filp_open+0x17e/0x3c0 [ 716.350645][ T1653] ? may_open_dev+0xf0/0xf0 [ 716.356249][ T1653] ? do_raw_spin_lock+0x120/0x2b0 [ 716.361295][ T1653] ? rwlock_bug.part.0+0x90/0x90 [ 716.367347][ T1653] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 716.373614][ T1653] ? _raw_spin_unlock+0x24/0x40 [ 716.379857][ T1653] ? alloc_fd+0x2da/0x650 [ 716.386060][ T1653] ? do_sys_openat2+0x16d/0x420 [ 716.390922][ T1653] ? build_open_flags+0x680/0x680 [ 716.397108][ T1653] ? __x64_sys_openat+0x13f/0x1f0 [ 716.402154][ T1653] ? __ia32_sys_open+0x1c0/0x1c0 [ 716.408272][ T1653] ? syscall_enter_from_user_mode+0x1d/0x50 [ 716.414902][ T1653] ? do_syscall_64+0x2d/0x70 [ 716.419506][ T1653] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 716.426834][ T1653] [ 716.426834][ T1653] Showing all locks held in the system: [ 716.435589][ T1653] 1 lock held by khungtaskd/1653: [ 716.440615][ T1653] #0: ffffffff8b793ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x28c [ 716.452838][ T1653] 1 lock held by in:imklog/8189: [ 716.458495][ T1653] #0: ffff8880262b2af0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 [ 716.468564][ T1653] 4 locks held by syz-executor827/8500: [ 716.474814][ T1653] [ 716.477145][ T1653] ============================================= [ 716.477145][ T1653] [ 716.486641][ T1653] Kernel panic - not syncing: hung_task: blocked tasks [ 716.493579][ T1653] CPU: 1 PID: 1653 Comm: khungtaskd Not tainted 5.10.0-next-20201217-syzkaller #0 [ 716.502776][ T1653] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 716.512829][ T1653] Call Trace: [ 716.516130][ T1653] dump_stack+0x107/0x163 [ 716.520462][ T1653] panic+0x343/0x77f [ 716.524347][ T1653] ? __warn_printk+0xf3/0xf3 [ 716.528925][ T1653] ? watchdog.cold+0x146/0x31d [ 716.533675][ T1653] watchdog.cold+0x157/0x31d [ 716.538251][ T1653] ? trace_sched_process_hang+0x2a0/0x2a0 [ 716.543958][ T1653] kthread+0x3b1/0x4a0 [ 716.548016][ T1653] ? kthread_create_worker_on_cpu+0xf0/0xf0 [ 716.553911][ T1653] ret_from_fork+0x1f/0x30 [ 716.559003][ T1653] Kernel Offset: disabled [ 716.563325][ T1653] Rebooting in 86400 seconds..