[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 56.581011][ T26] audit: type=1800 audit(1574825417.057:25): pid=8702 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 56.622376][ T26] audit: type=1800 audit(1574825417.067:26): pid=8702 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 56.661506][ T26] audit: type=1800 audit(1574825417.067:27): pid=8702 uid=0 auid=4294967295 ses=4294967295 subj==unconfined 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 '10.128.0.126' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 66.349459][ T8857] [drm:drm_calc_timestamping_constants] *ERROR* crtc 32: Can't calculate constants, dotclock = 0! [ 66.361361][ C0] ------------[ cut here ]------------ [ 66.366938][ C0] WARNING: CPU: 0 PID: 8857 at drivers/gpu/drm/vkms/vkms_crtc.c:23 vkms_vblank_simulate+0x33a/0x3c0 [ 66.377860][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 66.384980][ C0] CPU: 0 PID: 8857 Comm: syz-executor540 Not tainted 5.4.0-syzkaller #0 [ 66.393289][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 66.403351][ C0] Call Trace: [ 66.406616][ C0] [ 66.409456][ C0] dump_stack+0x197/0x210 [ 66.413774][ C0] ? vkms_vblank_simulate+0x270/0x3c0 [ 66.419126][ C0] panic+0x2e3/0x75c [ 66.423000][ C0] ? add_taint.cold+0x16/0x16 [ 66.427660][ C0] ? printk+0xba/0xed [ 66.431627][ C0] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 66.437177][ C0] ? __warn.cold+0x14/0x35 [ 66.441578][ C0] ? __warn+0xd9/0x1d0 [ 66.445642][ C0] ? vkms_vblank_simulate+0x33a/0x3c0 [ 66.450998][ C0] __warn.cold+0x2f/0x35 [ 66.455223][ C0] ? report_bug.cold+0x63/0xad [ 66.459978][ C0] ? vkms_vblank_simulate+0x33a/0x3c0 [ 66.465331][ C0] report_bug+0x289/0x300 [ 66.469643][ C0] do_error_trap+0x11b/0x200 [ 66.474216][ C0] do_invalid_op+0x37/0x50 [ 66.478615][ C0] ? vkms_vblank_simulate+0x33a/0x3c0 [ 66.483966][ C0] invalid_op+0x23/0x30 [ 66.488104][ C0] RIP: 0010:vkms_vblank_simulate+0x33a/0x3c0 [ 66.494068][ C0] Code: a1 00 00 00 49 8b 94 24 50 02 00 00 4c 89 f1 bf 02 00 00 00 48 c7 c6 a0 a4 03 88 e8 50 89 b5 ff e9 dd fe ff ff e8 b6 6c 7c fd <0f> 0b e9 7e fd ff ff e8 4a aa b8 fd e9 f4 fd ff ff 48 8b 7d d0 e8 [ 66.513742][ C0] RSP: 0018:ffff8880ae809dd0 EFLAGS: 00010006 [ 66.519787][ C0] RAX: ffff8880998e42c0 RBX: ffff8880a38056e8 RCX: ffffffff83f7a145 [ 66.527764][ C0] RDX: 0000000000010000 RSI: ffffffff83f7a3ca RDI: 0000000000000007 [ 66.535727][ C0] RBP: ffff8880ae809e08 R08: ffff8880998e42c0 R09: ffff8880998e4b50 [ 66.543688][ C0] R10: fffffbfff138ed40 R11: ffffffff89c76a07 R12: 0000000000072163 [ 66.551649][ C0] R13: ffff8880a3805740 R14: ffff8880a3804be8 R15: 0000000000000000 [ 66.559642][ C0] ? vkms_vblank_simulate+0xb5/0x3c0 [ 66.564936][ C0] ? vkms_vblank_simulate+0x33a/0x3c0 [ 66.570297][ C0] __hrtimer_run_queues+0x364/0xe40 [ 66.575494][ C0] ? vkms_disable_vblank+0x20/0x20 [ 66.580594][ C0] ? hrtimer_init+0x330/0x330 [ 66.585258][ C0] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 66.590974][ C0] ? ktime_get_update_offsets_now+0x2d3/0x440 [ 66.597031][ C0] hrtimer_interrupt+0x314/0x770 [ 66.601965][ C0] smp_apic_timer_interrupt+0x160/0x610 [ 66.607495][ C0] apic_timer_interrupt+0xf/0x20 [ 66.612430][ C0] [ 66.615353][ C0] RIP: 0010:_raw_spin_unlock_irqrestore+0x95/0xe0 [ 66.621762][ C0] Code: 48 c7 c0 60 2f f3 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 8a 9c 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 9c 58 f9 f9 65 8b 05 ed 58 ab 78 [ 66.641357][ C0] RSP: 0018:ffff888094ad7b08 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 [ 66.649760][ C0] RAX: 1ffffffff11e65ec RBX: 0000000000000286 RCX: 0000000000000000 [ 66.657727][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: 0000000000000286 [ 66.665687][ C0] RBP: ffff888094ad7b18 R08: ffff8880998e42c0 R09: 0000000000000000 [ 66.673638][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a38042f0 [ 66.681597][ C0] R13: 0000000000000000 R14: ffff8880a38042f0 R15: ffff888219314908 [ 66.689584][ C0] drm_vblank_get+0x150/0x1e0 [ 66.694408][ C0] drm_wait_vblank_ioctl+0x51a/0x1990 [ 66.699790][ C0] ? drm_dev_exit+0x22/0x60 [ 66.704294][ C0] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 66.710403][ C0] ? lock_downgrade+0x920/0x920 [ 66.715241][ C0] ? lock_acquire+0x190/0x410 [ 66.719929][ C0] ? drm_dev_alloc+0xd0/0xd0 [ 66.724505][ C0] drm_ioctl_kernel+0x244/0x300 [ 66.729338][ C0] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 66.735395][ C0] ? drm_setversion+0x8c0/0x8c0 [ 66.740265][ C0] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 66.746504][ C0] ? _copy_from_user+0x12c/0x1a0 [ 66.751436][ C0] compat_drm_wait_vblank+0xd6/0x190 [ 66.756712][ C0] ? compat_drm_mode_addfb2+0x1a0/0x1a0 [ 66.762241][ C0] ? compat_drm_mode_addfb2+0x1a0/0x1a0 [ 66.767769][ C0] drm_compat_ioctl+0x1eb/0x310 [ 66.772603][ C0] ? security_file_ioctl+0x8d/0xc0 [ 66.777842][ C0] ? compat_drm_setunique+0x10/0x10 [ 66.783038][ C0] __ia32_compat_sys_ioctl+0x195/0x620 [ 66.788492][ C0] do_fast_syscall_32+0x27b/0xdb3 [ 66.793508][ C0] entry_SYSENTER_compat+0x70/0x7f [ 66.798615][ C0] RIP: 0023:0xf7f58a39 [ 66.802673][ C0] Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 [ 66.822260][ C0] RSP: 002b:00000000ffca6f8c EFLAGS: 00000213 ORIG_RAX: 0000000000000036 [ 66.830652][ C0] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000c018643a [ 66.838609][ C0] RDX: 0000000020000100 RSI: 00000000080ef078 RDI: 00000000ffca6fe0 [ 66.846562][ C0] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 66.854515][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 66.862468][ C0] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 66.871973][ C0] Kernel Offset: disabled [ 66.876407][ C0] Rebooting in 86400 seconds..