[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.366308] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 27.009929] random: sshd: uninitialized urandom read (32 bytes read) [ 27.534168] random: sshd: uninitialized urandom read (32 bytes read) [ 27.920231] random: sshd: uninitialized urandom read (32 bytes read) [ 28.060296] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.45' (ECDSA) to the list of known hosts. [ 33.599281] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 05:30:08 parsed 1 programs [ 34.958529] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 05:30:10 executed programs: 0 [ 36.112878] IPVS: Creating netns size=2536 id=1 [ 36.240348] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 36.253337] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 36.297606] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 36.309089] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 36.353728] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 36.365169] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 36.377535] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 36.390192] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 36.435732] ip (3914) used greatest stack depth: 23528 bytes left [ 36.909126] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 36.935078] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 36.941166] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 36.948651] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 37.146638] hrtimer: interrupt took 10878 ns [ 37.299181] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.369653] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.485798] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.499617] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.719746] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.746780] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.773778] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.842476] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 37.947209] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 38.546281] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 38.554535] IP: [] l2tp_session_create+0xc60/0x16f0 [ 38.561254] PGD 1cb4cf067 [ 38.563902] PUD 1cb464067 PMD 0 [ 38.567394] [ 38.569027] Oops: 0002 [#1] PREEMPT SMP KASAN [ 38.573504] Dumping ftrace buffer: [ 38.577026] (ftrace buffer empty) [ 38.580714] Modules linked in: [ 38.584018] CPU: 0 PID: 4903 Comm: syz-executor0 Not tainted 4.9.122-g54068d6 #30 [ 38.591618] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.600974] task: ffff8801c7c73000 task.stack: ffff8801c7f40000 [ 38.607037] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 38.616161] RSP: 0018:ffff8801c7f47ab0 EFLAGS: 00010246 [ 38.621591] RAX: 0000000000000000 RBX: ffff8801c89c0a00 RCX: 1ffff10038f8e71d [ 38.628841] RDX: 1ffff10039138120 RSI: ffff8801c7c738c8 RDI: ffff8801c89c0900 [ 38.636118] RBP: ffff8801c7f47b50 R08: ffff8801c7c738e8 R09: 0000000000000000 [ 38.643369] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801c89c07d8 [ 38.650622] R13: 0000000000000000 R14: ffff8801c89c0780 R15: ffff8801c7f47c68 [ 38.657895] FS: 0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:00000000f7714b40 [ 38.666100] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 38.671988] CR2: 0000000000000080 CR3: 00000001d01ec000 CR4: 00000000001606f0 [ 38.679243] Stack: [ 38.681374] 0000000000000201 ffffffff836c9151 ffff8801c7f47ad0 ffffffff81237ecd [ 38.689465] ffff8801c89c0780 ffff8801c89c0b58 ffff8801c89c07d8 ffff8801c89c0b50 [ 38.697506] ffff8801c89c0ab0 ffff8801c89c07a0 0000000000000000 0000000000000000 [ 38.705529] Call Trace: [ 38.708104] [] ? l2tp_session_get+0x1d1/0x790 [ 38.714234] [] ? trace_hardirqs_on+0xd/0x10 [ 38.720191] [] pppol2tp_connect+0x10d7/0x18f0 [ 38.726326] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 38.732545] [] ? security_socket_connect+0x8f/0xc0 [ 38.739112] [] SYSC_connect+0x1b8/0x300 [ 38.744723] [] ? SYSC_bind+0x280/0x280 [ 38.750247] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 38.757244] [] SyS_connect+0x24/0x30 [ 38.762593] [] ? SyS_accept+0x30/0x30 [ 38.768040] [] do_fast_syscall_32+0x2f7/0x870 [ 38.774168] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 38.780819] [] entry_SYSENTER_compat+0x90/0xa2 [ 38.787030] 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 [ 38.814447] RIP [] l2tp_session_create+0xc60/0x16f0 [ 38.821237] RSP [ 38.824840] CR2: 0000000000000080 [ 38.829504] ---[ end trace c6a3144b2bbb7c21 ]--- [ 38.834581] Kernel panic - not syncing: Fatal exception [ 38.840279] Dumping ftrace buffer: [ 38.843820] (ftrace buffer empty) [ 38.847505] Kernel Offset: disabled [ 38.851108] Rebooting in 86400 seconds..