[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.882133] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.142532] random: sshd: uninitialized urandom read (32 bytes read) [ 21.645676] random: sshd: uninitialized urandom read (32 bytes read) [ 22.173902] random: sshd: uninitialized urandom read (32 bytes read) [ 22.318121] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.21' (ECDSA) to the list of known hosts. [ 27.881513] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 20:39:32 parsed 1 programs [ 29.072568] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 20:39:34 executed programs: 0 [ 30.228240] IPVS: Creating netns size=2536 id=1 [ 30.360151] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 30.371975] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 30.417362] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 30.429500] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 30.476343] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 30.487898] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 30.499923] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 30.514088] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 31.027708] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 31.053257] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 31.059797] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 31.066536] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 31.294804] hrtimer: interrupt took 11819 ns [ 31.331291] l2tp_core: tunl 4: sockfd_lookup(fd=7) returned -9 [ 31.370645] l2tp_core: tunl 4: sockfd_lookup(fd=7) returned -9 [ 31.388524] l2tp_core: tunl 4: sockfd_lookup(fd=7) returned -9 [ 31.417324] l2tp_core: tunl 4: sockfd_lookup(fd=7) returned -9 [ 31.439811] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 31.448142] IP: [<ffffffff836c8e30>] l2tp_session_create+0xc60/0x16f0 [ 31.454828] PGD 1d7974067 [ 31.457474] PUD 1da0a7067 PMD 0 [ 31.460982] [ 31.462613] Oops: 0002 [#1] PREEMPT SMP KASAN [ 31.467175] Dumping ftrace buffer: [ 31.470715] (ftrace buffer empty) [ 31.474400] Modules linked in: [ 31.477687] CPU: 1 PID: 4251 Comm: syz-executor0 Not tainted 4.9.123-g8dd3fc2 #27 [ 31.485281] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.494656] task: ffff8801d529c800 task.stack: ffff8801d52d0000 [ 31.500692] RIP: 0010:[<ffffffff836c8e30>] [<ffffffff836c8e30>] l2tp_session_create+0xc60/0x16f0 [ 31.509805] RSP: 0018:ffff8801d52d7ac0 EFLAGS: 00010246 [ 31.515231] RAX: 0000000000000000 RBX: ffff8801b95a6280 RCX: 1ffff1003aa53a1d [ 31.522561] RDX: 1ffff1003b0f85c0 RSI: ffff8801d529d0c8 RDI: ffff8801d87c2e00 [ 31.529812] RBP: ffff8801d52d7b60 R08: ffff8801d529d0e8 R09: 0000000000000000 [ 31.537169] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d87c2cd8 [ 31.544513] R13: 0000000000000000 R14: ffff8801d87c2c80 R15: ffff8801d52d7c78 [ 31.551792] FS: 00007ff9f7d59700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 31.560104] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 31.565967] CR2: 0000000000000080 CR3: 00000001d7295000 CR4: 00000000001606f0 [ 31.573226] Stack: [ 31.575351] 0000000000000201 ffffffff836ca141 ffff8801d52d7ae0 ffffffff81237f0d [ 31.583411] ffff8801d87c2c80 ffff8801b95a63d8 ffff8801d87c2cd8 ffff8801b95a63d0 [ 31.591394] ffff8801b95a6330 ffff8801d87c2ca0 0000000000000000 0000000000000000 [ 31.599379] Call Trace: [ 31.601952] [<ffffffff836ca141>] ? l2tp_session_get+0x1d1/0x790 [ 31.608087] [<ffffffff81237f0d>] ? trace_hardirqs_on+0xd/0x10 [ 31.614050] [<ffffffff836cdfe7>] pppol2tp_connect+0x10d7/0x18f0 [ 31.620294] [<ffffffff836ccf10>] ? pppol2tp_seq_show+0xc30/0xc30 [ 31.626614] [<ffffffff8100301a>] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.633207] [<ffffffff81f2110b>] ? check_preemption_disabled+0x3b/0x170 [ 31.640096] [<ffffffff83a02629>] ? retint_kernel+0x2d/0x2d [ 31.645804] [<ffffffff81cf90cf>] ? security_socket_connect+0x8f/0xc0 [ 31.652368] [<ffffffff8301e958>] SYSC_connect+0x1b8/0x300 [ 31.658034] [<ffffffff8301e7a0>] ? SYSC_bind+0x280/0x280 [ 31.663615] [<ffffffff812db710>] ? do_futex+0x17c0/0x17c0 [ 31.669233] [<ffffffff815dc2cd>] ? fd_install+0x4d/0x60 [ 31.674736] [<ffffffff83021224>] SyS_connect+0x24/0x30 [ 31.680085] [<ffffffff83021200>] ? SyS_accept+0x30/0x30 [ 31.685518] [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 [ 31.691215] [<ffffffff83a01c93>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 31.698117] 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 [ 31.725251] RIP [<ffffffff836c8e30>] l2tp_session_create+0xc60/0x16f0 [ 31.732031] RSP <ffff8801d52d7ac0> [ 31.735635] CR2: 0000000000000080 [ 31.740466] ---[ end trace 5399e0d954b481af ]--- [ 31.745281] Kernel panic - not syncing: Fatal exception [ 31.750862] Dumping ftrace buffer: [ 31.754386] (ftrace buffer empty) [ 31.758076] Kernel Offset: disabled [ 31.761690] Rebooting in 86400 seconds..