[ 71.462337][ T26] audit: type=1800 audit(1576719027.019:25): pid=9171 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 71.496117][ T26] audit: type=1800 audit(1576719027.019:26): pid=9171 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 71.535696][ T26] audit: type=1800 audit(1576719027.019:27): pid=9171 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. [ 72.070488][ T9239] sshd (9239) used greatest stack depth: 22728 bytes left [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.141' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 81.514044][ T9326] BUG: kernel NULL pointer dereference, address: 0000000000000002 [ 81.521858][ T9326] #PF: supervisor write access in kernel mode [ 81.528075][ T9326] #PF: error_code(0x0002) - not-present page [ 81.534088][ T9326] PGD 95648067 P4D 95648067 PUD a2ab2067 PMD 0 [ 81.540338][ T9326] Oops: 0002 [#1] PREEMPT SMP KASAN [ 81.545653][ T9326] CPU: 0 PID: 9326 Comm: syz-executor434 Not tainted 5.5.0-rc2-next-20191218-syzkaller #0 [ 81.555521][ T9326] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 81.565583][ T9326] RIP: 0010:mem_serial_out+0x70/0x90 [ 81.570878][ T9326] 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 f1 d5 ce fd eb c0 e8 4a d6 ce fd [ 81.591081][ T9326] RSP: 0018:ffffc9000207f8e8 EFLAGS: 00010202 [ 81.597129][ T9326] RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 0000000000000000 [ 81.605081][ T9326] RDX: 1ffffffff1821c96 RSI: ffffffff83e460b6 RDI: ffffffff8c10e4b0 [ 81.613059][ T9326] RBP: ffffc9000207f900 R08: ffff888094784180 R09: ffffed10144ca1c6 [ 81.621026][ T9326] R10: ffffed10144ca1c5 R11: ffff8880a2650e2b R12: ffffffff8c10e470 [ 81.629003][ T9326] R13: 0000000000000001 R14: ffffffff8c10e470 R15: ffffffff8c10e5c8 [ 81.636993][ T9326] FS: 0000000000a2a880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 [ 81.645898][ T9326] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 81.652456][ T9326] CR2: 0000000000000002 CR3: 00000000a7fbd000 CR4: 00000000001406f0 [ 81.660409][ T9326] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 81.668358][ T9326] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 81.676304][ T9326] Call Trace: [ 81.679665][ T9326] serial8250_clear_fifos.part.0+0x3a/0xb0 [ 81.685460][ T9326] serial8250_do_startup+0x426/0x1cf0 [ 81.690823][ T9326] serial8250_startup+0x62/0x80 [ 81.695663][ T9326] uart_startup+0x479/0xa80 [ 81.700182][ T9326] ? uart_put_char+0x540/0x540 [ 81.705126][ T9326] ? serial8250_request_std_resource+0x159/0x3d0 [ 81.711456][ T9326] ? serial8250_probe+0x680/0x680 [ 81.716464][ T9326] ? serial8250_request_port+0x16/0x20 [ 81.721941][ T9326] uart_set_info_user+0x13b4/0x1cf0 [ 81.727158][ T9326] ? uart_port_activate+0x200/0x200 [ 81.733008][ T9326] tty_ioctl+0xf60/0x14f0 [ 81.737347][ T9326] ? tty_vhangup+0x30/0x30 [ 81.741747][ T9326] ? tomoyo_path_number_perm+0x454/0x520 [ 81.747378][ T9326] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 81.754055][ T9326] ? trace_hardirqs_on+0x67/0x240 [ 81.759079][ T9326] ? tty_vhangup+0x30/0x30 [ 81.764358][ T9326] do_vfs_ioctl+0x977/0x14e0 [ 81.768938][ T9326] ? compat_ioctl_preallocate+0x220/0x220 [ 81.774636][ T9326] ? chown_common+0x5c0/0x5c0 [ 81.779312][ T9326] ? __kasan_check_write+0x14/0x20 [ 81.784406][ T9326] ? up_read+0x1cd/0x810 [ 81.788636][ T9326] ? tomoyo_file_ioctl+0x23/0x30 [ 81.793573][ T9326] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 81.799800][ T9326] ? security_file_ioctl+0x8d/0xc0 [ 81.804901][ T9326] ksys_ioctl+0xab/0xd0 [ 81.809040][ T9326] __x64_sys_ioctl+0x73/0xb0 [ 81.813624][ T9326] do_syscall_64+0xfa/0x790 [ 81.818134][ T9326] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 81.824009][ T9326] RIP: 0033:0x440219 [ 81.828004][ T9326] 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 [ 81.847610][ T9326] RSP: 002b:00007ffe93fbc608 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 81.855998][ T9326] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440219 [ 81.863948][ T9326] RDX: 0000000020000240 RSI: 000000000000541f RDI: 0000000000000003 [ 81.872084][ T9326] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 81.880043][ T9326] R10: 0000000000401b30 R11: 0000000000000246 R12: 0000000000401aa0 [ 81.888007][ T9326] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 81.897017][ T9326] Modules linked in: [ 81.900909][ T9326] CR2: 0000000000000002 [ 81.906064][ T9326] ---[ end trace f4127722c55048a5 ]--- [ 81.912718][ T9326] RIP: 0010:mem_serial_out+0x70/0x90 [ 81.918181][ T9326] 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 f1 d5 ce fd eb c0 e8 4a d6 ce fd [ 81.938896][ T9326] RSP: 0018:ffffc9000207f8e8 EFLAGS: 00010202 [ 81.944963][ T9326] RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 0000000000000000 [ 81.952961][ T9326] RDX: 1ffffffff1821c96 RSI: ffffffff83e460b6 RDI: ffffffff8c10e4b0 [ 81.960948][ T9326] RBP: ffffc9000207f900 R08: ffff888094784180 R09: ffffed10144ca1c6 [ 81.968944][ T9326] R10: ffffed10144ca1c5 R11: ffff8880a2650e2b R12: ffffffff8c10e470 [ 81.976944][ T9326] R13: 0000000000000001 R14: ffffffff8c10e470 R15: ffffffff8c10e5c8 [ 81.985718][ T9326] FS: 0000000000a2a880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 [ 81.994638][ T9326] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 82.001251][ T9326] CR2: 0000000000000002 CR3: 00000000a7fbd000 CR4: 00000000001406f0 [ 82.009515][ T9326] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 82.017582][ T9326] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 82.025760][ T9326] Kernel panic - not syncing: Fatal exception [ 82.033353][ T9326] Kernel Offset: disabled [ 82.037691][ T9326] Rebooting in 86400 seconds..