[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.703199] audit: type=1800 audit(1548939775.376:25): pid=7797 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 40.741408] audit: type=1800 audit(1548939775.376:26): pid=7797 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 40.764666] audit: type=1800 audit(1548939775.376:27): pid=7797 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 syzkaller login: [ 45.677406] sshd (7933) used greatest stack depth: 19848 bytes left Warning: Permanently added '10.128.0.21' (ECDSA) to the list of known hosts. executing program [ 52.403694] INFO: trying to register non-static key. [ 52.408875] the code is fine but needs lockdep annotation. [ 52.414476] turning off the locking correctness validator. [ 52.420080] CPU: 1 PID: 7947 Comm: syz-executor093 Not tainted 5.0.0-rc4+ #53 [ 52.427344] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.436676] Call Trace: [ 52.439253] dump_stack+0x1db/0x2d0 [ 52.442863] ? dump_stack_print_info.cold+0x20/0x20 [ 52.447876] ? vprintk_func+0x86/0x189 [ 52.451742] register_lock_class+0x19dc/0x1e60 [ 52.456304] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 52.461304] ? bpf_prog_kallsyms_find+0xca/0x4b0 [ 52.466053] ? check_noncircular+0x20/0x20 [ 52.470266] ? module_enable_ro.part.0+0xe0/0xe0 [ 52.475005] ? __bpf_trace_xdp_cpumap_enqueue+0x40/0x40 [ 52.480353] ? check_preemption_disabled+0x48/0x290 [ 52.485349] ? lock_downgrade+0x910/0x910 [ 52.489474] ? check_noncircular+0x20/0x20 [ 52.493689] ? rcu_read_unlock_special+0x380/0x380 [ 52.498616] ? check_noncircular+0x20/0x20 [ 52.502835] ? print_usage_bug+0xd0/0xd0 [ 52.506904] ? is_bpf_text_address+0xd3/0x170 [ 52.511409] ? kernel_text_address+0x73/0xf0 [ 52.515815] ? __kernel_text_address+0xd/0x40 [ 52.520291] __lock_acquire+0x149/0x4a30 [ 52.524329] ? print_usage_bug+0xd0/0xd0 [ 52.528384] ? print_usage_bug+0xd0/0xd0 [ 52.532420] ? add_lock_to_list.isra.0+0x1c9/0x450 [ 52.537328] ? mark_held_locks+0x100/0x100 [ 52.541557] ? __lock_acquire+0x572/0x4a30 [ 52.545772] ? __lock_acquire+0x2514/0x4a30 [ 52.550071] ? mark_held_locks+0x100/0x100 [ 52.554288] ? mark_held_locks+0x100/0x100 [ 52.558515] ? mark_held_locks+0x100/0x100 [ 52.562726] ? mark_held_locks+0x100/0x100 [ 52.566939] ? add_lock_to_list.isra.0+0x450/0x450 [ 52.571849] ? add_lock_to_list.isra.0+0x450/0x450 [ 52.576761] ? save_stack+0x45/0xd0 [ 52.580369] ? __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 52.585450] ? print_usage_bug+0xd0/0xd0 [ 52.589505] ? try_wait_for_completion+0x146/0x190 [ 52.594415] lock_acquire+0x1db/0x570 [ 52.598195] ? __flush_work+0x762/0xa20 [ 52.602177] ? lock_release+0xc40/0xc40 [ 52.606135] ? try_wait_for_completion+0x146/0x190 [ 52.611047] ? trace_hardirqs_off_caller+0x300/0x300 [ 52.616129] ? lockdep_hardirqs_on+0x415/0x5d0 [ 52.620696] __flush_work+0x787/0xa20 [ 52.624476] ? __flush_work+0x762/0xa20 [ 52.628472] ? insert_work+0x620/0x620 [ 52.632342] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.637859] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.643390] ? check_preemption_disabled+0x48/0x290 [ 52.648389] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.653905] ? refcount_sub_and_test_checked+0x1fe/0x2f0 [ 52.659335] ? refcount_inc_not_zero_checked+0x2e0/0x2e0 [ 52.664772] ? __drm_atomic_helper_crtc_destroy_state+0xf3/0x340 [ 52.670897] flush_work+0x18/0x20 [ 52.674333] vkms_atomic_crtc_destroy_state+0x2d/0x40 [ 52.679503] drm_atomic_state_default_clear+0x37c/0xd60 [ 52.684847] drm_atomic_state_clear+0x9d/0xc0 [ 52.689319] __drm_atomic_state_free+0x3c/0xf0 [ 52.693884] drm_atomic_helper_set_config+0xe5/0x160 [ 52.698969] drm_mode_setcrtc+0x73c/0x1870 [ 52.703187] ? drm_mode_getcrtc+0x870/0x870 [ 52.707485] ? drm_unbind_agp+0x20/0x20 [ 52.711446] ? drm_unbind_agp+0x20/0x20 [ 52.715404] ? drm_dev_unregister+0x480/0x480 [ 52.719882] ? drm_lease_owner+0x45/0x60 [ 52.723924] ? drm_is_current_master+0x5c/0x140 [ 52.728586] drm_ioctl_kernel+0x278/0x340 [ 52.732713] ? drm_mode_getcrtc+0x870/0x870 [ 52.737014] ? drm_setversion+0x8c0/0x8c0 [ 52.741141] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 52.746667] ? _copy_from_user+0xdd/0x150 [ 52.750793] drm_ioctl+0x592/0xb50 [ 52.754315] ? drm_mode_getcrtc+0x870/0x870 [ 52.758615] ? drm_version+0x3d0/0x3d0 [ 52.762489] ? trace_hardirqs_on_caller+0x310/0x310 [ 52.767488] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.773006] ? check_preemption_disabled+0x48/0x290 [ 52.778003] ? drm_version+0x3d0/0x3d0 [ 52.781871] do_vfs_ioctl+0x107b/0x17d0 [ 52.785823] ? putname+0xef/0x130 [ 52.789256] ? ioctl_preallocate+0x2f0/0x2f0 [ 52.793652] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.799169] ? __fget_light+0x2db/0x420 [ 52.803121] ? fget_raw+0x20/0x20 [ 52.806576] ? do_syscall_64+0x8c/0x800 [ 52.810527] ? do_syscall_64+0x8c/0x800 [ 52.814484] ? lockdep_hardirqs_on+0x415/0x5d0 [ 52.819052] ? security_file_ioctl+0x93/0xc0 [ 52.823439] ksys_ioctl+0xab/0xd0 [ 52.826875] __x64_sys_ioctl+0x73/0xb0 [ 52.830741] do_syscall_64+0x1a3/0x800 [ 52.834608] ? syscall_return_slowpath+0x5f0/0x5f0 [ 52.839550] ? prepare_exit_to_usermode+0x232/0x3b0 [ 52.844546] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 52.849371] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 52.854539] RIP: 0033:0x443de9 [ 52.857711] 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 [ 52.876602] RSP: 002b:00007ffe69514388 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 52.884287] RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000443de9 [ 52.891544] RDX: 0000000020000180 RSI: 00000000c06864a2 RDI: 0000000000000003 [ 52.898790] RBP: 00000000006ce018 R08: 0000000000000000 R09: 00000000004002e0 [