[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 56.287037][ T27] audit: type=1800 audit(1575685201.992:25): pid=8733 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 56.307668][ T27] audit: type=1800 audit(1575685201.992:26): pid=8733 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 56.351368][ T27] audit: type=1800 audit(1575685202.002:27): pid=8733 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 '10.128.0.207' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 78.363357][ T8886] BUG: kernel NULL pointer dereference, address: 0000000000000002 [ 78.371175][ T8886] #PF: supervisor write access in kernel mode [ 78.377737][ T8886] #PF: error_code(0x0002) - not-present page [ 78.383688][ T8886] PGD 9937c067 P4D 9937c067 PUD 95bfa067 PMD 0 [ 78.389907][ T8886] Oops: 0002 [#1] PREEMPT SMP KASAN [ 78.395082][ T8886] CPU: 0 PID: 8886 Comm: syz-executor205 Not tainted 5.4.0-syzkaller #0 [ 78.403379][ T8886] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 78.413435][ T8886] RIP: 0010:mem_serial_out+0x70/0x90 [ 78.418695][ T8886] Code: e9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 19 48 63 db 49 03 5c 24 40 <44> 88 2b 5b 41 5c 41 5d 5d c3 e8 81 ed cf fd eb c0 e8 da ed cf fd [ 78.438278][ T8886] RSP: 0018:ffffc900020978e8 EFLAGS: 00010202 [ 78.444321][ T8886] RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 0000000000000000 [ 78.452310][ T8886] RDX: 1ffffffff181f40e RSI: ffffffff83e28776 RDI: ffffffff8c0fa070 [ 78.460263][ T8886] RBP: ffffc90002097900 R08: ffff88809632e400 R09: ffffed10431b01c6 [ 78.468218][ T8886] R10: ffffed10431b01c5 R11: ffff888218d80e2b R12: ffffffff8c0fa030 [ 78.476169][ T8886] R13: 0000000000000001 R14: ffffc90002097a40 R15: ffffffff8c0fa188 [ 78.484176][ T8886] FS: 0000000000af3880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 [ 78.493083][ T8886] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 78.499646][ T8886] CR2: 0000000000000002 CR3: 000000008d4c9000 CR4: 00000000001406f0 [ 78.507615][ T8886] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 78.515568][ T8886] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 78.523517][ T8886] Call Trace: [ 78.526788][ T8886] serial8250_clear_fifos.part.0+0x3a/0xb0 [ 78.532592][ T8886] serial8250_do_startup+0x426/0x1cf0 [ 78.537969][ T8886] serial8250_startup+0x62/0x80 [ 78.542813][ T8886] uart_startup+0x452/0x980 [ 78.547302][ T8886] ? uart_proc_show+0x13f0/0x13f0 [ 78.552301][ T8886] ? serial8250_request_std_resource+0x159/0x3d0 [ 78.558603][ T8886] ? serial8250_probe+0x680/0x680 [ 78.563604][ T8886] ? serial8250_request_port+0x16/0x20 [ 78.569038][ T8886] uart_set_info_user+0x13b4/0x1cf0 [ 78.574214][ T8886] ? uart_port_activate+0x200/0x200 [ 78.579384][ T8886] tty_ioctl+0xf60/0x14f0 [ 78.583690][ T8886] ? tty_vhangup+0x30/0x30 [ 78.588081][ T8886] ? tomoyo_path_number_perm+0x454/0x520 [ 78.593688][ T8886] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 78.599906][ T8886] ? tty_vhangup+0x30/0x30 [ 78.604298][ T8886] do_vfs_ioctl+0x977/0x14e0 [ 78.608880][ T8886] ? compat_ioctl_preallocate+0x220/0x220 [ 78.614582][ T8886] ? kmem_cache_free+0x26b/0x320 [ 78.619501][ T8886] ? putname+0xf4/0x130 [ 78.623635][ T8886] ? do_sys_open+0x31d/0x5d0 [ 78.628205][ T8886] ? tomoyo_file_ioctl+0x23/0x30 [ 78.633122][ T8886] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 78.639343][ T8886] ? security_file_ioctl+0x8d/0xc0 [ 78.644435][ T8886] ksys_ioctl+0xab/0xd0 [ 78.648567][ T8886] __x64_sys_ioctl+0x73/0xb0 [ 78.653142][ T8886] do_syscall_64+0xfa/0x790 [ 78.657624][ T8886] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 78.663491][ T8886] RIP: 0033:0x440219 [ 78.667373][ T8886] 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 78.686962][ T8886] RSP: 002b:00007ffd08edd7a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 78.695368][ T8886] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440219 [ 78.703354][ T8886] RDX: 0000000020000240 RSI: 000000000000541f RDI: 0000000000000003 [ 78.711306][ T8886] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 78.719337][ T8886] R10: 0000000000401b30 R11: 0000000000000246 R12: 0000000000401aa0 [ 78.727283][ T8886] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 78.735233][ T8886] Modules linked in: [ 78.739102][ T8886] CR2: 0000000000000002 [ 78.744086][ T8886] ---[ end trace eb54864659d194fb ]--- [ 78.749572][ T8886] RIP: 0010:mem_serial_out+0x70/0x90 [ 78.754915][ T8886] Code: e9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 19 48 63 db 49 03 5c 24 40 <44> 88 2b 5b 41 5c 41 5d 5d c3 e8 81 ed cf fd eb c0 e8 da ed cf fd [ 78.774578][ T8886] RSP: 0018:ffffc900020978e8 EFLAGS: 00010202 [ 78.780621][ T8886] RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 0000000000000000 [ 78.788641][ T8886] RDX: 1ffffffff181f40e RSI: ffffffff83e28776 RDI: ffffffff8c0fa070 [ 78.796627][ T8886] RBP: ffffc90002097900 R08: ffff88809632e400 R09: ffffed10431b01c6 [ 78.804628][ T8886] R10: ffffed10431b01c5 R11: ffff888218d80e2b R12: ffffffff8c0fa030 [ 78.812594][ T8886] R13: 0000000000000001 R14: ffffc90002097a40 R15: ffffffff8c0fa188 [ 78.820629][ T8886] FS: 0000000000af3880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 [ 78.829578][ T8886] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 78.836178][ T8886] CR2: 0000000000000002 CR3: 000000008d4c9000 CR4: 00000000001406f0 [ 78.844167][ T8886] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 78.852118][ T8886] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 78.860116][ T8886] Kernel panic - not syncing: Fatal exception [ 78.867551][ T8886] Kernel Offset: disabled [ 78.871870][ T8886] Rebooting in 86400 seconds..