[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [ 70.894076][ T27] audit: type=1800 audit(1575786351.360:25): pid=8809 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 70.914569][ T27] audit: type=1800 audit(1575786351.360:26): pid=8809 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 70.934986][ T27] audit: type=1800 audit(1575786351.360:27): pid=8809 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[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.38' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 80.754929][ T8964] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. [ 80.836053][ T8964] kasan: CONFIG_KASAN_INLINE enabled [ 80.841469][ T8964] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 80.849570][ T8964] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 80.856489][ T8964] CPU: 1 PID: 8964 Comm: syz-executor611 Not tainted 5.4.0-next-20191207-syzkaller #0 [ 80.866010][ T8964] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 80.876208][ T8964] RIP: 0010:skb_unlink+0xc4/0x160 [ 80.881216][ T8964] Code: 00 00 49 8d 7d 08 4c 8b 63 08 48 b8 00 00 00 00 00 fc ff df 48 c7 43 08 00 00 00 00 48 89 fa 48 c7 03 00 00 00 00 48 c1 ea 03 <80> 3c 02 00 75 58 4c 89 e2 4d 89 65 08 48 b8 00 00 00 00 00 fc ff [ 80.900811][ T8964] RSP: 0018:ffffc90001e07880 EFLAGS: 00010002 [ 80.906864][ T8964] RAX: dffffc0000000000 RBX: ffff8880a4804940 RCX: ffffffff815bf9f9 [ 80.914811][ T8964] RDX: 0000000000000001 RSI: 0000000000000286 RDI: 0000000000000008 [ 80.922766][ T8964] RBP: ffffc90001e078a8 R08: 0000000000000004 R09: fffff520003c0efd [ 80.930718][ T8964] R10: fffff520003c0efc R11: 0000000000000003 R12: 0000000000000000 [ 80.938670][ T8964] R13: 0000000000000000 R14: ffff8880a30819e8 R15: ffffc90001e07950 [ 80.946632][ T8964] FS: 00007f1c941d9700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 [ 80.955550][ T8964] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 80.962118][ T8964] CR2: 00000000209ff000 CR3: 00000000a953f000 CR4: 00000000001406e0 [ 80.970174][ T8964] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 80.978124][ T8964] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 80.986090][ T8964] Call Trace: [ 80.989368][ T8964] kcm_recvmsg+0x462/0x560 [ 80.993770][ T8964] ? kcm_splice_read+0x360/0x360 [ 80.998694][ T8964] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 81.004919][ T8964] ? import_iovec+0x267/0x410 [ 81.009576][ T8964] ? kcm_splice_read+0x360/0x360 [ 81.014511][ T8964] sock_recvmsg_nosec+0x89/0xb0 [ 81.019344][ T8964] ? __sock_tx_timestamp+0xd0/0xd0 [ 81.024452][ T8964] ____sys_recvmsg+0x236/0x550 [ 81.029211][ T8964] ? move_addr_to_user+0x210/0x210 [ 81.034301][ T8964] ? move_addr_to_kernel.part.0+0x110/0x110 [ 81.040177][ T8964] ? __kasan_check_read+0x11/0x20 [ 81.045180][ T8964] ___sys_recvmsg+0xe4/0x150 [ 81.049749][ T8964] ? recvmsg_copy_msghdr+0x80/0x80 [ 81.054849][ T8964] ? __might_fault+0x12b/0x1e0 [ 81.059600][ T8964] ? ksys_dup3+0x3e0/0x3e0 [ 81.064018][ T8964] ? lock_downgrade+0x920/0x920 [ 81.068858][ T8964] do_recvmmsg+0x27e/0x7a0 [ 81.073313][ T8964] ? ___sys_recvmsg+0x150/0x150 [ 81.078151][ T8964] ? __fd_install+0x1bc/0x640 [ 81.082816][ T8964] ? lock_downgrade+0x920/0x920 [ 81.087655][ T8964] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 81.093920][ T8964] ? __fd_install+0x1fb/0x640 [ 81.098626][ T8964] __sys_recvmmsg+0x259/0x270 [ 81.103290][ T8964] ? __ia32_sys_recvmsg+0xb0/0xb0 [ 81.108299][ T8964] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 81.113738][ T8964] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 81.119177][ T8964] ? do_syscall_64+0x26/0x790 [ 81.123837][ T8964] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 81.129907][ T8964] ? do_syscall_64+0x26/0x790 [ 81.134569][ T8964] __x64_sys_recvmmsg+0xe6/0x140 [ 81.139503][ T8964] do_syscall_64+0xfa/0x790 [ 81.143990][ T8964] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 81.149873][ T8964] RIP: 0033:0x446a69 [ 81.153753][ T8964] Code: e8 5c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 81.173338][ T8964] RSP: 002b:00007f1c941d8d98 EFLAGS: 00000246 ORIG_RAX: 000000000000012b [ 81.181729][ T8964] RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 0000000000446a69 [ 81.189682][ T8964] RDX: 0400000000000310 RSI: 0000000020003540 RDI: 0000000000000005 [ 81.197637][ T8964] RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000 [ 81.205596][ T8964] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c [ 81.213557][ T8964] R13: 00000000002b0095 R14: 0000a50000000000 R15: 0000000300000018 [ 81.221516][ T8964] Modules linked in: [ 81.225447][ T8964] ---[ end trace 2e0d807b6e384251 ]--- [ 81.230940][ T8964] RIP: 0010:skb_unlink+0xc4/0x160 [ 81.235947][ T8964] Code: 00 00 49 8d 7d 08 4c 8b 63 08 48 b8 00 00 00 00 00 fc ff df 48 c7 43 08 00 00 00 00 48 89 fa 48 c7 03 00 00 00 00 48 c1 ea 03 <80> 3c 02 00 75 58 4c 89 e2 4d 89 65 08 48 b8 00 00 00 00 00 fc ff [ 81.255531][ T8964] RSP: 0018:ffffc90001e07880 EFLAGS: 00010002 [ 81.261585][ T8964] RAX: dffffc0000000000 RBX: ffff8880a4804940 RCX: ffffffff815bf9f9 [ 81.269543][ T8964] RDX: 0000000000000001 RSI: 0000000000000286 RDI: 0000000000000008 [ 81.277497][ T8964] RBP: ffffc90001e078a8 R08: 0000000000000004 R09: fffff520003c0efd [ 81.285452][ T8964] R10: fffff520003c0efc R11: 0000000000000003 R12: 0000000000000000 [ 81.293412][ T8964] R13: 0000000000000000 R14: ffff8880a30819e8 R15: ffffc90001e07950 [ 81.301367][ T8964] FS: 00007f1c941d9700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 [ 81.310277][ T8964] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 81.316838][ T8964] CR2: 00000000209ff000 CR3: 00000000a953f000 CR4: 00000000001406e0 [ 81.324789][ T8964] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 81.332742][ T8964] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 81.340694][ T8964] Kernel panic - not syncing: Fatal exception [ 81.348127][ T8964] Kernel Offset: disabled [ 81.352467][ T8964] Rebooting in 86400 seconds..