[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   16.804616] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   28.820103] random: sshd: uninitialized urandom read (32 bytes read)
[   29.197461] random: sshd: uninitialized urandom read (32 bytes read)
[   29.600945] random: sshd: uninitialized urandom read (32 bytes read)
[   44.159574] random: sshd: uninitialized urandom read (32 bytes read)
Warning: Permanently added '10.128.10.31' (ECDSA) to the list of known hosts.
[   49.669492] random: sshd: uninitialized urandom read (32 bytes read)
2018/08/23 20:02:02 parsed 1 programs
[   50.773022] random: cc1: uninitialized urandom read (8 bytes read)
2018/08/23 20:02:04 executed programs: 0
[   51.870014] IPVS: Creating netns size=2536 id=1
[   51.995977] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready
[   52.007588] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready
[   52.052078] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready
[   52.063997] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready
[   52.107756] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready
[   52.119203] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready
[   52.131532] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready
[   52.144593] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready
[   52.192102] ip (3937) used greatest stack depth: 23976 bytes left
[   52.649209] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
[   52.673961] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready
[   52.680055] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready
[   52.687686] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
[   52.893261] hrtimer: interrupt took 23907 ns
[   53.068545] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
[   53.076819] IP: [<ffffffff836c8f30>] l2tp_session_create+0xc60/0x16f0
[   53.083499] PGD 1da29c067 [   53.086155] PUD 1d68cc067 
PMD 0 [   53.089637] 
[   53.091259] Oops: 0002 [#1] PREEMPT SMP KASAN
[   53.095724] Dumping ftrace buffer:
[   53.099374]    (ftrace buffer empty)
[   53.103062] Modules linked in:
[   53.106361] CPU: 0 PID: 4291 Comm: syz-executor0 Not tainted 4.9.123-g7fa8c15 #80
[   53.113955] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   53.123289] task: ffff8801d4f43000 task.stack: ffff8801b5750000
[   53.129321] RIP: 0010:[<ffffffff836c8f30>]  [<ffffffff836c8f30>] l2tp_session_create+0xc60/0x16f0
[   53.138429] RSP: 0018:ffff8801b5757ac0  EFLAGS: 00010246
[   53.143853] RAX: 0000000000000000 RBX: ffff8801d501db80 RCX: 1ffff1003a9e871d
[   53.151098] RDX: 1ffff1003a94a0d0 RSI: ffff8801d4f438c8 RDI: ffff8801d4a50680
[   53.158342] RBP: ffff8801b5757b60 R08: ffff8801d4f438e8 R09: 0000000000000000
[   53.165586] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d4a50558
[   53.172833] R13: 0000000000000000 R14: ffff8801d4a50500 R15: ffff8801b5757c78
[   53.180081] FS:  00007f541d3ad700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
[   53.188320] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   53.194191] CR2: 0000000000000080 CR3: 00000001da384000 CR4: 00000000001606f0
[   53.201438] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   53.208704] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   53.215948] Stack:
[   53.218072]  0000000000000201 ffffffff836ca241 ffff8801b5757ae0 ffffffff81237f0d
[   53.226071]  ffff8801d4a50500 ffff8801d501dcd8 ffff8801d4a50558 ffff8801d501dcd0
[   53.234053]  ffff8801d501dc30 ffff8801d4a50520 0000000000000000 0000000000000000
[   53.242042] Call Trace:
[   53.244603]  [<ffffffff836ca241>] ? l2tp_session_get+0x1d1/0x790
[   53.250723]  [<ffffffff81237f0d>] ? trace_hardirqs_on+0xd/0x10
[   53.256672]  [<ffffffff836ce0e7>] pppol2tp_connect+0x10d7/0x18f0
[   53.262791]  [<ffffffff836cd010>] ? pppol2tp_seq_show+0xc30/0xc30
[   53.268998]  [<ffffffff81f2110b>] ? check_preemption_disabled+0x3b/0x170
[   53.275920]  [<ffffffff83a02729>] ? retint_kernel+0x2d/0x2d
[   53.281613]  [<ffffffff81cf90cf>] ? security_socket_connect+0x8f/0xc0
[   53.288182]  [<ffffffff8301ea38>] SYSC_connect+0x1b8/0x300
[   53.293787]  [<ffffffff8301e880>] ? SYSC_bind+0x280/0x280
[   53.299303]  [<ffffffff812db710>] ? do_futex+0x17c0/0x17c0
[   53.304905]  [<ffffffff83020910>] ? move_addr_to_kernel+0x50/0x50
[   53.311228]  [<ffffffff83021314>] SyS_connect+0x24/0x30
[   53.316566]  [<ffffffff830212f0>] ? SyS_accept+0x30/0x30
[   53.321989]  [<ffffffff81006316>] do_syscall_64+0x1a6/0x490
[   53.327684]  [<ffffffff83a01d93>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
[   53.334578] Code: 00 00 49 8d be 80 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 7b 09 00 00 49 8b 86 80 01 00 00 <f0> ff 80 80 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 55 d0 
[   53.361415] RIP  [<ffffffff836c8f30>] l2tp_session_create+0xc60/0x16f0
[   53.368180]  RSP <ffff8801b5757ac0>
[   53.371777] CR2: 0000000000000080
[   53.375436] ---[ end trace 442c8af5a4bc4fb3 ]---
[   53.380171] Kernel panic - not syncing: Fatal exception
[   53.385936] Dumping ftrace buffer:
[   53.389453]    (ftrace buffer empty)
[   53.393144] Kernel Offset: disabled
[   53.396743] Rebooting in 86400 seconds..