[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.503585] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.789089] random: sshd: uninitialized urandom read (32 bytes read) [ 19.997980] random: sshd: uninitialized urandom read (32 bytes read) [ 20.500278] random: sshd: uninitialized urandom read (32 bytes read) [ 22.250889] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.28' (ECDSA) to the list of known hosts. [ 27.916071] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 17:56:51 parsed 1 programs [ 28.743661] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 17:56:52 executed programs: 0 [ 29.394738] IPVS: Creating netns size=2536 id=1 [ 29.523810] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 29.536041] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 29.581141] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 29.592665] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 29.638376] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 29.649862] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 29.662410] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 29.676287] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 30.195437] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 30.220830] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 30.227131] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 30.234761] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 30.432596] hrtimer: interrupt took 37229 ns [ 30.479518] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 30.504714] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 30.541033] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 30.549246] IP: [] l2tp_session_create+0xc60/0x16f0 [ 30.556034] PGD 1da21f067 [ 30.558678] PUD 1da285067 PMD 0 [ 30.562270] [ 30.563970] Oops: 0002 [#1] PREEMPT SMP KASAN [ 30.568446] Dumping ftrace buffer: [ 30.571962] (ftrace buffer empty) [ 30.575683] Modules linked in: [ 30.578975] CPU: 1 PID: 4235 Comm: syz-executor0 Not tainted 4.9.123-g8dd3fc2 #79 [ 30.586566] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.596139] task: ffff8801d51a1800 task.stack: ffff8801d5338000 [ 30.602172] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 30.611409] RSP: 0018:ffff8801d533fac0 EFLAGS: 00010246 [ 30.616913] RAX: 0000000000000000 RBX: ffff8801d981f400 RCX: 1ffff1003aa3441d [ 30.624212] RDX: 1ffff1003b303f50 RSI: ffff8801d51a20c8 RDI: ffff8801d981fa80 [ 30.631577] RBP: ffff8801d533fb60 R08: ffff8801d51a20e8 R09: 0000000000000000 [ 30.638832] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d981f958 [ 30.646086] R13: 0000000000000000 R14: ffff8801d981f900 R15: ffff8801d533fc78 [ 30.653446] FS: 00007fbf601f4700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 30.661654] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.667656] CR2: 0000000000000080 CR3: 00000001d77a2000 CR4: 00000000001606f0 [ 30.674909] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.682154] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.689505] Stack: [ 30.691645] 0000000000000201 ffffffff836ca141 ffff8801d533fae0 ffffffff81237f0d [ 30.699673] ffff8801d981f900 ffff8801d981f558 ffff8801d981f958 ffff8801d981f550 [ 30.707707] ffff8801d981f4b0 ffff8801d981f920 0000000000000000 0000000000000000 [ 30.715721] Call Trace: [ 30.718296] [] ? l2tp_session_get+0x1d1/0x790 [ 30.724423] [] ? trace_hardirqs_on+0xd/0x10 [ 30.730379] [] pppol2tp_connect+0x10d7/0x18f0 [ 30.736508] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 30.742723] [] ? security_socket_connect+0x8f/0xc0 [ 30.749286] [] SYSC_connect+0x1b8/0x300 [ 30.754893] [] ? SYSC_bind+0x280/0x280 [ 30.760417] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 30.767240] [] ? do_futex+0x17c0/0x17c0 [ 30.772846] [] ? check_preemption_disabled+0x3b/0x170 [ 30.779671] [] ? retint_kernel+0x2d/0x2d [ 30.785362] [] ? do_futex+0x17c0/0x17c0 [ 30.790969] [] SyS_connect+0x24/0x30 [ 30.796312] [] ? SyS_accept+0x30/0x30 [ 30.801742] [] do_syscall_64+0x1a6/0x490 [ 30.807434] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 30.814337] 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 [ 30.841527] RIP [] l2tp_session_create+0xc60/0x16f0 [ 30.848302] RSP [ 30.851906] CR2: 0000000000000080 [ 30.857779] ---[ end trace e3b3e88aee9cf0b1 ]--- [ 30.862922] Kernel panic - not syncing: Fatal exception [ 30.868647] Dumping ftrace buffer: [ 30.872163] (ftrace buffer empty) [ 30.875843] Kernel Offset: disabled [ 30.879440] Rebooting in 86400 seconds..