[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.240904][ T26] audit: type=1800 audit(1574591199.100:25): pid=7702 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 40.282262][ T26] audit: type=1800 audit(1574591199.100:26): pid=7702 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 40.313716][ T26] audit: type=1800 audit(1574591199.110:27): pid=7702 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 Warning: Permanently added '10.128.0.177' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 49.183054][ T7858] 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. executing program executing program [ 49.594602][ T7864] kasan: CONFIG_KASAN_INLINE enabled [ 49.600040][ T7864] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 49.608092][ T7864] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 49.615062][ T7864] CPU: 0 PID: 7864 Comm: syz-executor546 Not tainted 5.4.0-rc8-syzkaller #0 [ 49.623723][ T7864] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.633773][ T7864] RIP: 0010:skb_unlink+0xa1/0x110 [ 49.638777][ T7864] Code: 80 3c 30 00 74 05 e8 6e 74 d6 fb 49 8b 5c 24 08 4d 8d 6f 08 ba 10 00 00 00 4c 89 e7 31 f6 e8 d6 45 d6 fb 4c 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ef e8 e0 74 d6 fb 49 89 5f 08 48 89 d8 [ 49.658398][ T7864] RSP: 0018:ffff88808d5ffac0 EFLAGS: 00010002 [ 49.664472][ T7864] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 [ 49.672432][ T7864] RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff8880a41cf090 [ 49.680393][ T7864] RBP: ffff88808d5ffaf8 R08: dffffc0000000000 R09: ffff8880a41cf080 [ 49.688351][ T7864] R10: ffffed1014839e12 R11: 0000000000000000 R12: ffff8880a41cf080 [ 49.696313][ T7864] R13: 0000000000000008 R14: dffffc0000000000 R15: 0000000000000000 [ 49.704276][ T7864] FS: 00007efeff2bc700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 [ 49.713187][ T7864] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 49.719751][ T7864] CR2: 00000000209ff000 CR3: 0000000099267000 CR4: 00000000001406f0 [ 49.727708][ T7864] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 49.735656][ T7864] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 49.743628][ T7864] Call Trace: [ 49.746904][ T7864] kcm_recvmsg+0x312/0x510 [ 49.751302][ T7864] ? kcm_sendmsg+0x2130/0x2130 [ 49.756041][ T7864] sock_recvmsg_nosec+0x8a/0xa0 [ 49.760870][ T7864] ___sys_recvmsg+0x5af/0x910 [ 49.765521][ T7864] ? __might_fault+0xf9/0x160 [ 49.770188][ T7864] do_recvmmsg+0x2ca/0x7c0 [ 49.774585][ T7864] ? __fpregs_load_activate+0x195/0x220 [ 49.780104][ T7864] __x64_sys_recvmmsg+0x130/0x1c0 [ 49.785105][ T7864] do_syscall_64+0xf7/0x1c0 [ 49.789584][ T7864] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 49.795459][ T7864] RIP: 0033:0x446a39 [ 49.799327][ T7864] 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 [ 49.818912][ T7864] RSP: 002b:00007efeff2bbd98 EFLAGS: 00000246 ORIG_RAX: 000000000000012b [ 49.827311][ T7864] RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 0000000000446a39 [ 49.835256][ T7864] RDX: 0400000000000310 RSI: 0000000020003540 RDI: 0000000000000005 [ 49.843198][ T7864] RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000 [ 49.852096][ T7864] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c [ 49.860051][ T7864] R13: 00000000002b0095 R14: 0000a50000000000 R15: 0000000300000018 [ 49.868000][ T7864] Modules linked in: [ 49.871876][ T7864] ---[ end trace b917cb5253b5b0db ]--- [ 49.877316][ T7864] RIP: 0010:skb_unlink+0xa1/0x110 [ 49.882311][ T7864] Code: 80 3c 30 00 74 05 e8 6e 74 d6 fb 49 8b 5c 24 08 4d 8d 6f 08 ba 10 00 00 00 4c 89 e7 31 f6 e8 d6 45 d6 fb 4c 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ef e8 e0 74 d6 fb 49 89 5f 08 48 89 d8 [ 49.901895][ T7864] RSP: 0018:ffff88808d5ffac0 EFLAGS: 00010002 [ 49.907939][ T7864] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 [ 49.915892][ T7864] RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff8880a41cf090 [ 49.923838][ T7864] RBP: ffff88808d5ffaf8 R08: dffffc0000000000 R09: ffff8880a41cf080 [ 49.931784][ T7864] R10: ffffed1014839e12 R11: 0000000000000000 R12: ffff8880a41cf080 [ 49.939732][ T7864] R13: 0000000000000008 R14: dffffc0000000000 R15: 0000000000000000 [ 49.947695][ T7864] FS: 00007efeff2bc700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 [ 49.956604][ T7864] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 49.963156][ T7864] CR2: 00000000209ff000 CR3: 0000000099267000 CR4: 00000000001406f0 [ 49.971100][ T7864] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 49.979045][ T7864] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 49.986988][ T7864] Kernel panic - not syncing: Fatal exception [ 49.994203][ T7864] Kernel Offset: disabled [ 49.998523][ T7864] Rebooting in 86400 seconds..