[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 44.101207] audit: type=1800 audit(1548928911.575:25): pid=8011 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 44.133294] audit: type=1800 audit(1548928911.575:26): pid=8011 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 44.152413] audit: type=1800 audit(1548928911.585:27): pid=8011 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 syzkaller login: [ 48.111737] sshd (8147) used greatest stack depth: 19848 bytes left Warning: Permanently added '10.128.0.184' (ECDSA) to the list of known hosts. executing program [ 54.915173] INFO: trying to register non-static key. [ 54.920306] the code is fine but needs lockdep annotation. [ 54.925917] turning off the locking correctness validator. [ 54.931545] CPU: 1 PID: 8161 Comm: syz-executor462 Not tainted 5.0.0-rc4+ #53 [ 54.938795] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.948125] Call Trace: [ 54.950714] dump_stack+0x1db/0x2d0 [ 54.954331] ? dump_stack_print_info.cold+0x20/0x20 [ 54.959358] ? vprintk_func+0x86/0x189 [ 54.963230] register_lock_class+0x19dc/0x1e60 [ 54.967796] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 54.972795] ? bpf_prog_kallsyms_find+0xca/0x4b0 [ 54.977533] ? check_noncircular+0x20/0x20 [ 54.981748] ? module_enable_ro.part.0+0xe0/0xe0 [ 54.986531] ? __bpf_trace_xdp_cpumap_enqueue+0x40/0x40 [ 54.991911] ? check_preemption_disabled+0x48/0x290 [ 54.996921] ? lock_downgrade+0x910/0x910 [ 55.001064] ? check_noncircular+0x20/0x20 [ 55.005282] ? rcu_read_unlock_special+0x380/0x380 [ 55.010192] ? check_noncircular+0x20/0x20 [ 55.014444] ? print_usage_bug+0xd0/0xd0 [ 55.018499] ? is_bpf_text_address+0xd3/0x170 [ 55.022983] ? kernel_text_address+0x73/0xf0 [ 55.027371] ? __kernel_text_address+0xd/0x40 [ 55.031859] __lock_acquire+0x149/0x4a30 [ 55.035897] ? print_usage_bug+0xd0/0xd0 [ 55.039936] ? print_usage_bug+0xd0/0xd0 [ 55.043977] ? add_lock_to_list.isra.0+0x1c9/0x450 [ 55.048889] ? mark_held_locks+0x100/0x100 [ 55.053101] ? __lock_acquire+0x572/0x4a30 [ 55.057326] ? __lock_acquire+0x2514/0x4a30 [ 55.061655] ? mark_held_locks+0x100/0x100 [ 55.065868] ? mark_held_locks+0x100/0x100 [ 55.070085] ? mark_held_locks+0x100/0x100 [ 55.074295] ? mark_held_locks+0x100/0x100 [ 55.078507] ? add_lock_to_list.isra.0+0x450/0x450 [ 55.083448] ? add_lock_to_list.isra.0+0x450/0x450 [ 55.088374] ? save_stack+0x45/0xd0 [ 55.091993] ? __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 55.097138] ? print_usage_bug+0xd0/0xd0 [ 55.101196] ? try_wait_for_completion+0x146/0x190 [ 55.106128] lock_acquire+0x1db/0x570 [ 55.109928] ? __flush_work+0x762/0xa20 [ 55.113882] ? lock_release+0xc40/0xc40 [ 55.117837] ? try_wait_for_completion+0x146/0x190 [ 55.122747] ? trace_hardirqs_off_caller+0x300/0x300 [ 55.127830] ? lockdep_hardirqs_on+0x415/0x5d0 [ 55.132394] __flush_work+0x787/0xa20 [ 55.136187] ? __flush_work+0x762/0xa20 [ 55.140157] ? insert_work+0x620/0x620 [ 55.144024] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.149540] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.155059] ? check_preemption_disabled+0x48/0x290 [ 55.160056] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.165600] ? refcount_sub_and_test_checked+0x1fe/0x2f0 [ 55.171030] ? refcount_inc_not_zero_checked+0x2e0/0x2e0 [ 55.176465] ? __drm_atomic_helper_crtc_destroy_state+0xf3/0x340 [ 55.182593] flush_work+0x18/0x20 [ 55.186124] vkms_atomic_crtc_destroy_state+0x2d/0x40 [ 55.191298] drm_atomic_state_default_clear+0x37c/0xd60 [ 55.196903] drm_atomic_state_clear+0x9d/0xc0 [ 55.201377] __drm_atomic_state_free+0x3c/0xf0 [ 55.205941] drm_atomic_helper_set_config+0xe5/0x160 [ 55.211026] drm_mode_setcrtc+0x73c/0x1870 [ 55.215244] ? drm_mode_getcrtc+0x870/0x870 [ 55.219546] ? drm_unbind_agp+0x20/0x20 [ 55.223500] ? drm_unbind_agp+0x20/0x20 [ 55.227845] ? drm_dev_unregister+0x480/0x480 [ 55.232326] ? drm_lease_owner+0x45/0x60 [ 55.236380] ? drm_is_current_master+0x5c/0x140 [ 55.241032] drm_ioctl_kernel+0x278/0x340 [ 55.245162] ? drm_mode_getcrtc+0x870/0x870 [ 55.249465] ? drm_setversion+0x8c0/0x8c0 [ 55.253593] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 55.259111] ? _copy_from_user+0xdd/0x150 [ 55.263236] drm_ioctl+0x592/0xb50 [ 55.266754] ? drm_mode_getcrtc+0x870/0x870 [ 55.271074] ? drm_version+0x3d0/0x3d0 [ 55.274961] ? smack_privileged+0xd0/0xd0 [ 55.279091] ? drm_version+0x3d0/0x3d0 [ 55.282960] do_vfs_ioctl+0x107b/0x17d0 [ 55.286913] ? smk_curacc+0x7f/0xa0 [ 55.290538] ? ioctl_preallocate+0x2f0/0x2f0 [ 55.294924] ? smack_inode_setattr+0x290/0x290 [ 55.299487] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.305005] ? __fget_light+0x2db/0x420 [ 55.308980] ? do_syscall_64+0x8c/0x800 [ 55.312934] ? do_syscall_64+0x8c/0x800 [ 55.316889] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.322424] ? security_file_ioctl+0x93/0xc0 [ 55.326814] ksys_ioctl+0xab/0xd0 [ 55.330247] __x64_sys_ioctl+0x73/0xb0 [ 55.334226] do_syscall_64+0x1a3/0x800 [ 55.338113] ? syscall_return_slowpath+0x5f0/0x5f0 [ 55.343039] ? prepare_exit_to_usermode+0x232/0x3b0 [ 55.348049] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 55.353218] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 55.358387] RIP: 0033:0x443de9 [ 55.361559] 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 [ 55.380439] RSP: 002b:00007ffc7dd115a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 55.388124] RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000443de9 [ 55.395373] RDX: 0000000020000180 RSI: 00000000c06864a2 RDI: 0000000000000003 [ 55.402636] RBP: 00000000006ce018 R08: 0000000000000000 R09: 00000000004002e0 [ 55.409901] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401af0 [ 5