[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 53.641248][ T26] audit: type=1800 audit(1559571685.833:25): pid=8368 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 53.664389][ T26] audit: type=1800 audit(1559571685.843:26): pid=8368 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 53.692080][ T26] audit: type=1800 audit(1559571685.853:27): pid=8368 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.94' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 64.400008][ T8521] [drm:drm_calc_timestamping_constants] *ERROR* crtc 31: Can't calculate constants, dotclock = 0! [ 64.411825][ C0] WARNING: CPU: 0 PID: 8521 at drivers/gpu/drm/vkms/vkms_crtc.c:40 vkms_vblank_simulate+0x25c/0x2c0 [ 64.422700][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 64.429270][ C0] CPU: 0 PID: 8521 Comm: syz-executor032 Not tainted 5.2.0-rc3 #18 [ 64.437136][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.447176][ C0] Call Trace: [ 64.450450][ C0] [ 64.453297][ C0] dump_stack+0x172/0x1f0 [ 64.457671][ C0] ? vkms_vblank_simulate+0x1d0/0x2c0 [ 64.463022][ C0] panic+0x2cb/0x744 [ 64.466897][ C0] ? __warn_printk+0xf3/0xf3 [ 64.471467][ C0] ? vkms_vblank_simulate+0x25c/0x2c0 [ 64.476815][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 64.483037][ C0] ? __warn.cold+0x5/0x4d [ 64.487359][ C0] ? __warn+0xe8/0x1d0 [ 64.491411][ C0] ? vkms_vblank_simulate+0x25c/0x2c0 [ 64.496776][ C0] __warn.cold+0x20/0x4d [ 64.501014][ C0] ? vkms_vblank_simulate+0x25c/0x2c0 [ 64.506363][ C0] report_bug+0x263/0x2b0 [ 64.510673][ C0] do_error_trap+0x11b/0x200 [ 64.515328][ C0] do_invalid_op+0x37/0x50 [ 64.519733][ C0] ? vkms_vblank_simulate+0x25c/0x2c0 [ 64.525121][ C0] invalid_op+0x14/0x20 [ 64.529268][ C0] RIP: 0010:vkms_vblank_simulate+0x25c/0x2c0 [ 64.535227][ C0] Code: c7 c7 40 2c c0 87 e8 33 08 ba ff e9 32 fe ff ff e8 39 0f 93 fd 48 8b 45 d0 49 89 86 40 02 00 00 e9 7a ff ff ff e8 24 0f 93 fd <0f> 0b e9 f4 fe ff ff e8 e8 ac cb fd e9 3a fe ff ff e8 3e ad cb fd [ 64.555071][ C0] RSP: 0018:ffff8880ae809dd8 EFLAGS: 00010006 [ 64.561116][ C0] RAX: ffff888091a8c280 RBX: ffff8880ae826d80 RCX: ffffffff83dd967d [ 64.569080][ C0] RDX: 0000000000010000 RSI: ffffffff83dd978c RDI: 0000000000000007 [ 64.577047][ C0] RBP: ffff8880ae809e08 R08: ffff888091a8c280 R09: 0000000000000002 [ 64.585000][ C0] R10: fffffbfff14c2b64 R11: ffff888091a8c280 R12: 000000000006b0ba [ 64.592950][ C0] R13: ffff8880a38b1810 R14: 0000000000000000 R15: ffff8880a38b0d08 [ 64.600924][ C0] ? vkms_vblank_simulate+0x14d/0x2c0 [ 64.606295][ C0] ? vkms_vblank_simulate+0x25c/0x2c0 [ 64.611651][ C0] ? vkms_vblank_simulate+0x25c/0x2c0 [ 64.617004][ C0] __hrtimer_run_queues+0x33b/0xdd0 [ 64.622219][ C0] ? vkms_disable_vblank+0x20/0x20 [ 64.627315][ C0] ? hrtimer_start_range_ns+0xc70/0xc70 [ 64.632840][ C0] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 64.638535][ C0] ? ktime_get_update_offsets_now+0x2d3/0x440 [ 64.644585][ C0] hrtimer_interrupt+0x314/0x770 [ 64.651242][ C0] smp_apic_timer_interrupt+0x111/0x550 [ 64.656776][ C0] apic_timer_interrupt+0xf/0x20 [ 64.661687][ C0] [ 64.664609][ C0] RIP: 0010:_raw_spin_unlock_irqrestore+0x95/0xe0 [ 64.671003][ C0] Code: 48 c7 c0 f0 73 b2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 39 48 83 3d 62 d0 95 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 7c d8 30 fa 65 8b 05 dd 59 e5 78 [ 64.690591][ C0] RSP: 0018:ffff8880a7cf7928 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 [ 64.698981][ C0] RAX: 1ffffffff1164e7e RBX: 0000000000000286 RCX: 0000000000000000 [ 64.706957][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: 0000000000000286 [ 64.714908][ C0] RBP: ffff8880a7cf7938 R08: ffff888091a8c280 R09: 0000000000000000 [ 64.722858][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a38b0430 [ 64.730807][ C0] R13: 0000000000000000 R14: ffff8880a38b0430 R15: ffff8880a3f121c8 [ 64.738800][ C0] drm_vblank_get+0x150/0x1e0 [ 64.743464][ C0] drm_wait_vblank_ioctl+0x513/0x1950 [ 64.749037][ C0] ? drm_dev_exit+0x22/0x60 [ 64.755281][ C0] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 64.764089][ C0] ? lock_downgrade+0x880/0x880 [ 64.768934][ C0] ? drm_dev_exit+0x60/0x60 [ 64.773428][ C0] drm_ioctl_kernel+0x244/0x300 [ 64.778258][ C0] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 64.784303][ C0] ? drm_setversion+0x8c0/0x8c0 [ 64.789138][ C0] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 64.795356][ C0] ? _copy_from_user+0xdd/0x150 [ 64.800186][ C0] drm_ioctl+0x54e/0xa60 [ 64.804425][ C0] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 64.810495][ C0] ? drm_version+0x3d0/0x3d0 [ 64.815067][ C0] ? tomoyo_execute_permission+0x4a0/0x4a0 [ 64.820864][ C0] ? smack_log+0x415/0x540 [ 64.825269][ C0] ? drm_version+0x3d0/0x3d0 [ 64.829836][ C0] do_vfs_ioctl+0xd5f/0x1380 [ 64.834414][ C0] ? ioctl_preallocate+0x210/0x210 [ 64.839499][ C0] ? smack_file_ioctl+0x196/0x310 [ 64.844519][ C0] ? smack_inode_rename+0x2d0/0x2d0 [ 64.849692][ C0] ? rcu_read_lock_sched_held+0x110/0x130 [ 64.855388][ C0] ? kmem_cache_free+0x221/0x260 [ 64.860305][ C0] ? do_sys_open+0x31d/0x5d0 [ 64.864875][ C0] ? tomoyo_file_ioctl+0x23/0x30 [ 64.869796][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 64.876018][ C0] ? security_file_ioctl+0x8d/0xc0 [ 64.881143][ C0] ksys_ioctl+0xab/0xd0 [ 64.885289][ C0] __x64_sys_ioctl+0x73/0xb0 [ 64.889861][ C0] do_syscall_64+0xfd/0x680 [ 64.894346][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 64.900213][ C0] RIP: 0033:0x443e89 [ 64.904091][ C0] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b d8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 64.923679][ C0] RSP: 002b:00007ffcb332ba98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 64.932067][ C0] RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000443e89 [ 64.940021][ C0] RDX: 0000000020000040 RSI: 00000000c02c563a RDI: 0000000000000003 [ 64.947969][ C0] RBP: 00000000006ce018 R08: 0000000000000000 R09: 00000000004002e0 [ 64.955921][ C0] R10: 000000000000000f R11: 0000000000000246 R12: 0000000000401b90 [ 64.963878][ C0] R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 [ 64.973235][ C0] Kernel Offset: disabled [ 64.977635][ C0] Rebooting in 86400 seconds..