[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 41.345367] audit: type=1800 audit(1545829007.589:25): pid=8089 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 41.365371] audit: type=1800 audit(1545829007.599:26): pid=8089 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 41.402250] audit: type=1800 audit(1545829007.599:27): pid=8089 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 '10.128.0.17' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 50.527341] INFO: trying to register non-static key. [ 50.532496] the code is fine but needs lockdep annotation. [ 50.538097] turning off the locking correctness validator. [ 50.543706] CPU: 0 PID: 8240 Comm: syz-executor791 Not tainted 4.20.0+ #167 [ 50.550784] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.560139] Call Trace: [ 50.562749] dump_stack+0x1d3/0x2c6 [ 50.566362] ? dump_stack_print_info.cold.1+0x20/0x20 [ 50.571550] ? vprintk_func+0x85/0x181 [ 50.575425] register_lock_class+0x21c5/0x29d0 [ 50.579991] ? kasan_check_read+0x11/0x20 [ 50.584120] ? graph_lock+0x9c/0x270 [ 50.587818] ? add_lock_to_list.isra.26+0x4b0/0x4b0 [ 50.592833] ? check_noncircular+0x20/0x20 [ 50.597056] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 50.602061] ? bpf_prog_kallsyms_find+0xde/0x4a0 [ 50.606827] ? module_enable_ro.part.68+0xe0/0xe0 [ 50.611662] ? check_noncircular+0x20/0x20 [ 50.615894] ? check_noncircular+0x20/0x20 [ 50.620109] ? noop_count+0x40/0x40 [ 50.623716] ? lock_pin_lock+0x350/0x350 [ 50.627758] ? kasan_check_read+0x11/0x20 [ 50.631908] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 50.636937] ? bpf_prog_kallsyms_find+0xde/0x4a0 [ 50.641682] ? module_enable_ro.part.68+0xe0/0xe0 [ 50.646505] ? __bpf_trace_xdp_cpumap_enqueue+0x40/0x40 [ 50.651881] ? kernel_text_address+0x79/0xf0 [ 50.656287] ? is_bpf_text_address+0xac/0x170 [ 50.660781] ? lock_downgrade+0x900/0x900 [ 50.664917] ? rcu_read_unlock_special+0x1d0/0x1d0 [ 50.669830] ? kasan_check_read+0x11/0x20 [ 50.673961] ? rcu_dynticks_curr_cpu_in_eqs+0xa2/0x170 [ 50.679228] ? print_usage_bug+0xc0/0xc0 [ 50.683271] ? unwind_dump+0x190/0x190 [ 50.687149] ? print_usage_bug+0xc0/0xc0 [ 50.691194] ? kernel_text_address+0x79/0xf0 [ 50.695586] ? print_usage_bug+0xc0/0xc0 [ 50.699630] ? print_usage_bug+0xc0/0xc0 [ 50.703676] __lock_acquire+0x184/0x4c20 [ 50.707721] ? __lock_acquire+0x62f/0x4c20 [ 50.711938] ? add_lock_to_list.isra.26+0x1ec/0x4b0 [ 50.716937] ? mark_held_locks+0x130/0x130 [ 50.721151] ? mark_held_locks+0x130/0x130 [ 50.725371] ? __lock_acquire+0x282a/0x4c20 [ 50.729677] ? mark_held_locks+0x130/0x130 [ 50.733893] ? mark_held_locks+0x130/0x130 [ 50.738114] ? mark_held_locks+0x130/0x130 [ 50.742328] ? mark_held_locks+0x130/0x130 [ 50.746560] ? graph_lock+0x270/0x270 [ 50.750359] ? graph_lock+0x270/0x270 [ 50.754157] ? print_usage_bug+0xc0/0xc0 [ 50.758204] ? trace_hardirqs_on+0xbd/0x310 [ 50.762559] ? kasan_check_read+0x11/0x20 [ 50.766731] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 50.772163] ? graph_lock+0x270/0x270 [ 50.775946] ? print_usage_bug+0xc0/0xc0 [ 50.779989] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 50.785080] ? graph_lock+0x270/0x270 [ 50.788876] ? lockdep_hardirqs_on+0x421/0x5c0 [ 50.793442] ? find_held_lock+0x36/0x1c0 [ 50.797497] lock_acquire+0x1ed/0x520 [ 50.801281] ? __flush_work+0x72d/0x9b0 [ 50.805246] ? lock_release+0xa00/0xa00 [ 50.809211] ? lockdep_hardirqs_on+0x421/0x5c0 [ 50.813786] ? trace_hardirqs_on+0xbd/0x310 [ 50.818094] ? kasan_check_read+0x11/0x20 [ 50.822274] ? try_wait_for_completion+0x149/0x180 [ 50.827203] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 50.832638] ? lockdep_hardirqs_on+0x421/0x5c0 [ 50.837207] __flush_work+0x752/0x9b0 [ 50.840987] ? __flush_work+0x72d/0x9b0 [ 50.844957] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 50.850043] ? graph_lock+0x270/0x270 [ 50.853823] ? try_wait_for_completion+0x149/0x180 [ 50.858746] ? insert_work+0x4c0/0x4c0 [ 50.862614] ? complete_all+0x70/0x70 [ 50.866403] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 50.871922] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 50.877442] ? refcount_sub_and_test_checked+0x203/0x310 [ 50.882875] ? refcount_inc_not_zero_checked+0x2f0/0x2f0 [ 50.888316] ? __drm_atomic_helper_crtc_destroy_state+0xf3/0x340 [ 50.894445] flush_work+0x17/0x20 [ 50.897887] vkms_atomic_crtc_destroy_state+0x2b/0x40 [ 50.903081] drm_atomic_state_default_clear+0x37c/0xda0 [ 50.908458] drm_atomic_state_clear+0x9f/0xd0 [ 50.912940] __drm_atomic_state_free+0x3a/0xf0 [ 50.917509] drm_atomic_helper_set_config+0xe6/0x160 [ 50.922604] drm_mode_setcrtc+0x767/0x1890 [ 50.926823] ? drm_mode_getcrtc+0x870/0x870 [ 50.931152] ? drm_unbind_agp+0x20/0x20 [ 50.935111] ? lock_downgrade+0x900/0x900 [ 50.939271] ? lock_release+0xa00/0xa00 [ 50.943243] ? __might_fault+0x12b/0x1e0 [ 50.947288] ? drm_is_current_master+0x5c/0x140 [ 50.951966] drm_ioctl_kernel+0x278/0x330 [ 50.956108] ? drm_mode_getcrtc+0x870/0x870 [ 50.960436] ? drm_setversion+0x8b0/0x8b0 [ 50.964587] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 50.970112] ? _copy_from_user+0xdf/0x150 [ 50.974243] drm_ioctl+0x58f/0xb90 [ 50.977788] ? drm_mode_getcrtc+0x870/0x870 [ 50.982116] ? drm_version+0x3d0/0x3d0 [ 50.986000] ? trace_hardirqs_off+0xb8/0x310 [ 50.990393] ? smack_privileged+0xd0/0xd0 [ 50.994538] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 51.000080] ? drm_version+0x3d0/0x3d0 [ 51.003954] do_vfs_ioctl+0x1de/0x1790 [ 51.007823] ? rcu_lockdep_current_cpu_online+0x1a4/0x210 [ 51.013341] ? ioctl_preallocate+0x300/0x300 [ 51.017752] ? smk_curacc+0x7f/0xa0 [ 51.021359] ? smack_file_ioctl+0x210/0x3c0 [ 51.025662] ? fget_raw+0x20/0x20 [ 51.029099] ? smack_file_lock+0x2e0/0x2e0 [ 51.033316] ? rcu_read_lock_sched_held+0x108/0x120 [ 51.038321] ? do_syscall_64+0x9a/0x820 [ 51.042273] ? do_syscall_64+0x9a/0x820 [ 51.046232] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 51.051750] ? security_file_ioctl+0x94/0xc0 [ 51.056171] ksys_ioctl+0xa9/0xd0 [ 51.059605] __x64_sys_ioctl+0x73/0xb0 [ 51.063471] do_syscall_64+0x1b9/0x820 [ 51.067339] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 51.072696] ? syscall_return_slowpath+0x5e0/0x5e0 [ 51.077606] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 51.082435] ? trace_hardirqs_on_caller+0x310/0x310 [ 51.087450] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 51.092449] ? prepare_exit_to_usermode+0x291/0x3b0 [ 51.097445] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 51.102303] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 51.107477] RIP: 0033:0x443e59 [ 51.110654] 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 [ 51.