[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.108199] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 14.537735] random: sshd: uninitialized urandom read (32 bytes read) [ 14.870050] random: sshd: uninitialized urandom read (32 bytes read) [ 15.405596] random: sshd: uninitialized urandom read (32 bytes read) [ 15.558658] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.56' (ECDSA) to the list of known hosts. [ 20.989697] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 05:04:36 parsed 1 programs [ 22.262452] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 05:04:38 executed programs: 0 [ 23.670046] IPVS: Creating netns size=2536 id=1 [ 23.791124] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 23.802717] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 23.844825] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 23.855970] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 23.899041] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 23.910176] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 23.921680] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 23.942736] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 24.428988] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 24.453749] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 24.459855] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 24.467152] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 24.678129] hrtimer: interrupt took 13949 ns [ 24.702139] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 24.977606] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 24.985817] IP: [] l2tp_session_create+0xc60/0x16f0 [ 24.992499] PGD 1d4a24067 [ 24.995142] PUD 1d4922067 PMD 0 [ 24.998617] [ 25.000236] Oops: 0002 [#1] PREEMPT SMP KASAN [ 25.004789] Dumping ftrace buffer: [ 25.008305] (ftrace buffer empty) [ 25.011995] Modules linked in: [ 25.015284] CPU: 0 PID: 4378 Comm: syz-executor0 Not tainted 4.9.122-g54068d6 #78 [ 25.022886] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.032223] task: ffff8801d4093000 task.stack: ffff8801d3ea8000 [ 25.038256] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 25.047417] RSP: 0018:ffff8801d3eafac0 EFLAGS: 00010246 [ 25.052843] RAX: 0000000000000000 RBX: ffff8801d468bb80 RCX: 1ffff1003a81271d [ 25.060089] RDX: 1ffff1003a848b50 RSI: ffff8801d40938c8 RDI: ffff8801d4245a80 [ 25.067379] RBP: ffff8801d3eafb60 R08: ffff8801d40938e8 R09: 0000000000000000 [ 25.074631] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d4245958 [ 25.082077] R13: 0000000000000000 R14: ffff8801d4245900 R15: ffff8801d3eafc78 [ 25.089391] FS: 00007fc9dd626700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 25.097651] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 25.103557] CR2: 0000000000000080 CR3: 00000001d57f6000 CR4: 00000000001606f0 [ 25.110867] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 25.118121] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 25.125372] Stack: [ 25.127503] 0000000000000201 ffffffff836c9151 ffff8801d3eafae0 ffffffff81237ecd [ 25.135507] ffff8801d4245900 ffff8801d468bcd8 ffff8801d4245958 ffff8801d468bcd0 [ 25.143485] ffff8801d468bc30 ffff8801d4245920 0000000000000000 0000000000000000 [ 25.151473] Call Trace: [ 25.154048] [] ? l2tp_session_get+0x1d1/0x790 [ 25.160187] [] ? trace_hardirqs_on+0xd/0x10 [ 25.166143] [] pppol2tp_connect+0x10d7/0x18f0 [ 25.172274] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 25.178487] [] ? check_preemption_disabled+0x3b/0x170 [ 25.185315] [] ? retint_kernel+0x2d/0x2d [ 25.191017] [] ? move_addr_to_kernel.part.13+0x35/0x110 [ 25.198010] [] ? security_socket_connect+0x8f/0xc0 [ 25.204574] [] SYSC_connect+0x1b8/0x300 [ 25.210184] [] ? SYSC_bind+0x280/0x280 [ 25.215707] [] ? do_futex+0x17c0/0x17c0 [ 25.221317] [] ? move_addr_to_kernel+0x50/0x50 [ 25.227536] [] SyS_connect+0x24/0x30 [ 25.232879] [] ? SyS_accept+0x30/0x30 [ 25.238364] [] do_syscall_64+0x1a6/0x490 [ 25.244064] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 25.251011] 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 [ 25.278319] RIP [] l2tp_session_create+0xc60/0x16f0 [ 25.285092] RSP [ 25.288691] CR2: 0000000000000080 [ 25.292878] ---[ end trace 12c11f100a2cf128 ]--- [ 25.297641] Kernel panic - not syncing: Fatal exception [ 25.303279] Dumping ftrace buffer: [ 25.306795] (ftrace buffer empty) [ 25.310479] Kernel Offset: disabled [ 25.314081] Rebooting in 86400 seconds..