[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.282902] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.181398] random: sshd: uninitialized urandom read (32 bytes read) [ 17.480638] random: sshd: uninitialized urandom read (32 bytes read) [ 18.002214] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.44' (ECDSA) to the list of known hosts. [ 23.687790] urandom_read: 1 callbacks suppressed [ 23.687793] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/23 04:39:10 parsed 1 programs [ 24.783472] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/23 04:39:11 executed programs: 0 [ 25.783340] IPVS: Creating netns size=2536 id=1 [ 25.910325] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 25.922756] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 25.966003] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 25.977404] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 26.021970] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 26.033218] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 26.045195] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 26.065961] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 26.571025] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 26.597250] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 26.603382] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 26.610768] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 26.822976] hrtimer: interrupt took 15187 ns [ 26.878825] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.098448] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.112426] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.402863] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.552538] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.594887] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.802370] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.866384] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 27.931853] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 27.940086] IP: [] l2tp_session_create+0xc60/0x16f0 [ 27.946807] PGD 1cdcbc067 [ 27.949452] PUD 1d06f8067 PMD 0 [ 27.952975] [ 27.954602] Oops: 0002 [#1] PREEMPT SMP KASAN [ 27.959087] Dumping ftrace buffer: [ 27.962610] (ftrace buffer empty) [ 27.966295] Modules linked in: [ 27.969609] CPU: 0 PID: 4676 Comm: syz-executor0 Not tainted 4.9.123-g8dd3fc2 #79 [ 27.977202] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.986775] task: ffff8801cef59800 task.stack: ffff8801cd370000 [ 27.992817] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 28.001929] RSP: 0018:ffff8801cd377ac0 EFLAGS: 00010246 [ 28.007355] RAX: 0000000000000000 RBX: ffff8801cd77af00 RCX: 1ffff10039deb41d [ 28.014608] RDX: 1ffff10039a77260 RSI: ffff8801cef5a0c8 RDI: ffff8801cd3b9300 [ 28.021855] RBP: ffff8801cd377b60 R08: ffff8801cef5a0e8 R09: 0000000000000000 [ 28.029102] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801cd3b91d8 [ 28.036350] R13: 0000000000000000 R14: ffff8801cd3b9180 R15: ffff8801cd377c78 [ 28.043604] FS: 00007f93a7689700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 28.051805] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.057663] CR2: 0000000000000080 CR3: 00000001cd0f2000 CR4: 00000000001606f0 [ 28.064910] Stack: [ 28.067037] 0000000000000201 ffffffff836ca141 ffff8801cd377ae0 ffffffff81237f0d [ 28.075062] ffff8801cd3b9180 ffff8801cd77b058 ffff8801cd3b91d8 ffff8801cd77b050 [ 28.083090] ffff8801cd77afb0 ffff8801cd3b91a0 0000000000000000 0000000000000000 [ 28.091094] Call Trace: [ 28.093969] [] ? l2tp_session_get+0x1d1/0x790 [ 28.100092] [] ? trace_hardirqs_on+0xd/0x10 [ 28.106301] [] pppol2tp_connect+0x10d7/0x18f0 [ 28.112439] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 28.118650] [] ? security_socket_connect+0x8f/0xc0 [ 28.125223] [] SYSC_connect+0x1b8/0x300 [ 28.130839] [] ? SYSC_bind+0x280/0x280 [ 28.136358] [] ? SyS_futex+0x229/0x310 [ 28.141874] [] ? do_futex+0x17c0/0x17c0 [ 28.147476] [] ? SyS_socket+0x121/0x1b0 [ 28.153076] [] ? move_addr_to_kernel+0x50/0x50 [ 28.159300] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.166129] [] SyS_connect+0x24/0x30 [ 28.171470] [] ? SyS_accept+0x30/0x30 [ 28.176896] [] do_syscall_64+0x1a6/0x490 [ 28.182590] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 28.189499] 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 ff 80 80 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 55 d0 [ 28.216376] RIP [] l2tp_session_create+0xc60/0x16f0 [ 28.223144] RSP [ 28.226761] CR2: 0000000000000080 [ 28.230962] ---[ end trace cc0bcab50557cf75 ]--- [ 28.235723] Kernel panic - not syncing: Fatal exception [ 28.241366] Dumping ftrace buffer: [ 28.244889] (ftrace buffer empty) [ 28.248575] Kernel Offset: disabled [ 28.252180] Rebooting in 86400 seconds..