[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Started OpenBSD Secure Shell server. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.65' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 698.173079][ T1144] INFO: task syz-executor563:6793 can't die for more than 143 seconds. [ 698.173102][ T1144] syz-executor563 R running task 27640 6793 6792 0x00004006 [ 698.173198][ T1144] Call Trace: [ 698.173248][ T1144] ? mark_lock+0xbc/0x1710 [ 698.173266][ T1144] ? kvm_sched_clock_read+0x14/0x40 [ 698.173283][ T1144] ? sched_clock+0x2a/0x40 [ 698.173301][ T1144] ? mark_held_locks+0x9f/0xe0 [ 698.173327][ T1144] ? check_preemption_disabled+0x50/0x130 [ 698.173401][ T1144] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 698.173419][ T1144] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 698.173435][ T1144] ? trace_hardirqs_on+0x5f/0x220 [ 698.173449][ T1144] ? lockdep_hardirqs_on+0x6a/0xe0 [ 698.173466][ T1144] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 698.173488][ T1144] ? bitfill_aligned+0x139/0x200 [ 698.173502][ T1144] ? bitfill_aligned+0x101/0x200 [ 698.173517][ T1144] ? bitfill_aligned+0x101/0x200 [ 698.173532][ T1144] ? bitfill_aligned+0x101/0x200 [ 698.173551][ T1144] ? cfb_fillrect+0x40b/0x7b0 [ 698.173565][ T1144] ? cfb_fillrect+0x7b0/0x7b0 [ 698.173589][ T1144] ? vga16fb_fillrect+0x683/0x193b [ 698.173605][ T1144] ? memcpy+0x39/0x60 [ 698.173622][ T1144] ? bit_clear_margins+0x2d5/0x4a0 [ 698.173637][ T1144] ? bit_bmove+0x210/0x210 [ 698.173655][ T1144] ? vga16fb_update_fix+0x4a0/0x4a0 [ 698.173681][ T1144] ? fbcon_clear_margins+0x1d5/0x230 [ 698.173700][ T1144] ? fbcon_switch+0xb6f/0x16c0 [ 698.173722][ T1144] ? fbcon_init+0x1b00/0x1b00 [ 698.173753][ T1144] ? fbcon_cursor+0x537/0x660 [ 698.173767][ T1144] ? kmalloc_array.constprop.0+0x20/0x20 [ 698.173787][ T1144] ? is_console_locked+0x5/0x10 [ 698.173803][ T1144] ? fbcon_set_origin+0x26/0x50 [ 698.173823][ T1144] ? redraw_screen+0x2af/0x770 [ 698.173840][ T1144] ? vga16fb_update_fix+0x4a0/0x4a0 [ 698.173856][ T1144] ? vc_init+0x430/0x430 [ 698.173876][ T1144] ? fbcon_set_palette+0x3a8/0x490 [ 698.173896][ T1144] ? fbcon_modechanged+0x575/0x710 [ 698.173918][ T1144] ? fbcon_update_vcs+0x3a/0x50 [ 698.173932][ T1144] ? fb_set_var+0xae8/0xd60 [ 698.173949][ T1144] ? fb_blank+0x190/0x190 [ 698.173964][ T1144] ? lock_release+0x8d0/0x8d0 [ 698.173983][ T1144] ? lock_is_held_type+0xb0/0xe0 [ 698.174009][ T1144] ? do_fb_ioctl+0x2f2/0x6c0 [ 698.174040][ T1144] ? _raw_spin_unlock_irqrestore+0x62/0xe0 [ 698.174057][ T1144] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 698.174072][ T1144] ? trace_hardirqs_on+0x5f/0x220 [ 698.174092][ T1144] ? do_fb_ioctl+0x33f/0x6c0 [ 698.174109][ T1144] ? fb_set_suspend+0x1a0/0x1a0 [ 698.174124][ T1144] ? tomoyo_execute_permission+0x470/0x470 [ 698.174155][ T1144] ? finish_mkwrite_fault+0x6b0/0x6b0 [ 698.174169][ T1144] ? rwlock_bug.part.0+0x90/0x90 [ 698.174192][ T1144] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 698.174208][ T1144] ? do_vfs_ioctl+0x27d/0x1090 [ 698.174242][ T1144] ? vmacache_update+0xce/0x140 [ 698.174263][ T1144] ? fb_ioctl+0xdd/0x130 [ 698.174278][ T1144] ? do_fb_ioctl+0x6c0/0x6c0 [ 698.174292][ T1144] ? ksys_ioctl+0x11a/0x180 [ 698.174310][ T1144] ? __x64_sys_ioctl+0x6f/0xb0 [ 698.174323][ T1144] ? lockdep_hardirqs_on+0x6a/0xe0 [ 698.174364][ T1144] ? do_syscall_64+0x60/0xe0 [ 698.174381][ T1144] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 698.174402][ T1144] [ 698.174402][ T1144] Showing all locks held in the system: [ 698.174416][ T1144] 1 lock held by khungtaskd/1144: [ 698.174421][ T1144] #0: ffffffff89bc3000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [ 698.174476][ T1144] 1 lock held by in:imklog/6484: [ 698.174482][ T1144] #0: ffff88809b8f0430 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 [ 698.174518][ T1144] 2 locks held by syz-executor563/6793: [ 698.174523][ T1144] [ 698.174528][ T1144] ============================================= [ 698.174528][ T1144] [ 698.174537][ T1144] Kernel panic - not syncing: hung_task: blocked tasks [ 698.174552][ T1144] CPU: 0 PID: 1144 Comm: khungtaskd Not tainted 5.8.0-rc3-next-20200701-syzkaller #0 [ 698.174561][ T1144] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 698.174565][ T1144] Call Trace: [ 698.174585][ T1144] dump_stack+0x18f/0x20d [ 698.174604][ T1144] panic+0x2e3/0x75c [ 698.174620][ T1144] ? __warn_printk+0xf3/0xf3 [ 698.174640][ T1144] ? watchdog.cold+0x22d/0x24b [ 698.174651][ T1144] ? watchdog+0xc59/0xf30 [ 698.174668][ T1144] watchdog.cold+0x23e/0x24b [ 698.174685][ T1144] ? trace_sched_process_hang+0x2e0/0x2e0 [ 698.174702][ T1144] kthread+0x3b5/0x4a0 [ 698.174716][ T1144] ? __kthread_bind_mask+0xc0/0xc0 [ 698.174729][ T1144] ? __kthread_bind_mask+0xc0/0xc0 [ 698.174748][ T1144] ret_from_fork+0x1f/0x30 [ 698.176231][ T1144] Kernel Offset: disabled [ 698.615305][ T1144] Rebooting in 86400 seconds..