[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 38.555554] audit: type=1800 audit(1550225263.048:25): pid=7704 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 38.593160] audit: type=1800 audit(1550225263.048:26): pid=7704 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 38.614924] audit: type=1800 audit(1550225263.048:27): pid=7704 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 '10.128.0.145' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 49.212657] INFO: trying to register non-static key. [ 49.217795] the code is fine but needs lockdep annotation. [ 49.223408] turning off the locking correctness validator. [ 49.229013] CPU: 0 PID: 7861 Comm: syz-executor177 Not tainted 5.0.0-rc6+ #72 [ 49.236262] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.245590] Call Trace: [ 49.248183] dump_stack+0x172/0x1f0 [ 49.251795] register_lock_class+0x1bdc/0x1bf0 [ 49.256357] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 49.261355] ? bpf_prog_kallsyms_find+0x50/0x2c0 [ 49.266104] ? check_noncircular+0x20/0x20 [ 49.270320] ? is_bpf_text_address+0xd3/0x170 [ 49.274826] ? kernel_text_address+0x73/0xf0 [ 49.279215] __lock_acquire+0x11f/0x4700 [ 49.283276] ? check_noncircular+0x20/0x20 [ 49.287496] ? mark_held_locks+0x100/0x100 [ 49.291728] ? __lock_acquire+0x53b/0x4700 [ 49.295981] ? __lock_acquire+0x53b/0x4700 [ 49.300196] ? __lock_acquire+0x53b/0x4700 [ 49.304413] lock_acquire+0x16f/0x3f0 [ 49.308197] ? __flush_work+0x61a/0x840 [ 49.312154] __flush_work+0x640/0x840 [ 49.315933] ? __flush_work+0x61a/0x840 [ 49.319932] ? try_wait_for_completion+0x9a/0xd0 [ 49.324670] ? insert_work+0x3a0/0x3a0 [ 49.328538] ? mark_held_locks+0xb1/0x100 [ 49.332667] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 49.338188] ? refcount_sub_and_test_checked+0x161/0x1f0 [ 49.343637] ? refcount_inc_checked+0x70/0x70 [ 49.348133] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 49.353581] ? __drm_atomic_helper_crtc_destroy_state+0xf3/0x340 [ 49.359707] flush_work+0x18/0x20 [ 49.363159] vkms_atomic_crtc_destroy_state+0x2d/0x40 [ 49.368333] drm_atomic_state_default_clear+0x37c/0xd60 [ 49.373688] drm_atomic_state_clear+0x9d/0xc0 [ 49.378182] __drm_atomic_state_free+0x3c/0xf0 [ 49.382748] drm_atomic_helper_set_config+0xe5/0x160 [ 49.387834] drm_mode_setcrtc+0x613/0x1490 [ 49.392049] ? mark_held_locks+0x100/0x100 [ 49.396266] ? drm_mode_getcrtc+0x870/0x870 [ 49.400598] ? drm_unbind_agp+0x20/0x20 [ 49.404550] ? find_held_lock+0x35/0x130 [ 49.408607] ? drm_unbind_agp+0x20/0x20 [ 49.412588] ? drm_lease_owner+0x45/0x60 [ 49.416646] ? drm_is_current_master+0x5c/0x140 [ 49.421301] drm_ioctl_kernel+0x23b/0x2e0 [ 49.425427] ? drm_mode_getcrtc+0x870/0x870 [ 49.429746] ? drm_setversion+0x8c0/0x8c0 [ 49.433916] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 49.439447] ? _copy_from_user+0xdd/0x150 [ 49.443598] drm_ioctl+0x545/0xa50 [ 49.447118] ? drm_mode_getcrtc+0x870/0x870 [ 49.451418] ? drm_version+0x3d0/0x3d0 [ 49.455286] ? debug_check_no_obj_freed+0x200/0x464 [ 49.460296] ? trace_hardirqs_off+0x62/0x220 [ 49.464698] ? drm_version+0x3d0/0x3d0 [ 49.468569] do_vfs_ioctl+0xd6e/0x1390 [ 49.472435] ? ioctl_preallocate+0x210/0x210 [ 49.476837] ? putname+0xef/0x130 [ 49.480273] ? rcu_read_lock_sched_held+0x110/0x130 [ 49.485268] ? kmem_cache_free+0x225/0x260 [ 49.489498] ? putname+0xf4/0x130 [ 49.492931] ? do_sys_open+0x31d/0x5d0 [ 49.496797] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 49.502318] ? security_file_ioctl+0x93/0xc0 [ 49.506705] ksys_ioctl+0xab/0xd0 [ 49.510138] __x64_sys_ioctl+0x73/0xb0 [ 49.514008] do_syscall_64+0x103/0x610 [ 49.517881] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 49.523049] RIP: 0033:0x443de9 [ 49.526222] 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 [ 49.545106] RSP: 002b:00007ffd74134798 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 49.552792] RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000443de9 [ 49.560041] RDX: 0000000020000180 RSI: 000000