[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.269132] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.712323] random: sshd: uninitialized urandom read (32 bytes read) [ 23.202950] random: sshd: uninitialized urandom read (32 bytes read) [ 23.682324] random: sshd: uninitialized urandom read (32 bytes read) [ 23.814504] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.38' (ECDSA) to the list of known hosts. [ 29.351203] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/23 13:00:45 parsed 1 programs [ 30.455545] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/23 13:00:47 executed programs: 0 [ 31.865506] IPVS: Creating netns size=2536 id=1 [ 31.990547] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 32.001861] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 32.045354] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 32.056926] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 32.099852] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 32.111492] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 32.123983] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 32.137967] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 32.637634] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 32.662834] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 32.669980] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 32.677502] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 32.922127] hrtimer: interrupt took 20654 ns [ 33.004125] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 33.207946] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 33.277910] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 33.286229] IP: [] l2tp_session_create+0xc60/0x16f0 [ 33.292978] PGD 1d35b1067 [ 33.295623] PUD 1d40d4067 PMD 0 [ 33.299098] [ 33.300719] Oops: 0002 [#1] PREEMPT SMP KASAN [ 33.305190] Dumping ftrace buffer: [ 33.308704] (ftrace buffer empty) [ 33.312388] Modules linked in: [ 33.315671] CPU: 0 PID: 4433 Comm: syz-executor0 Not tainted 4.9.123-g8dd3fc2 #27 [ 33.323260] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.332593] task: ffff8801d3cd6000 task.stack: ffff8801d3060000 [ 33.338622] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 33.347726] RSP: 0018:ffff8801d3067ac0 EFLAGS: 00010246 [ 33.353144] RAX: 0000000000000000 RBX: ffff8801d369ef00 RCX: 1ffff1003a79ad1d [ 33.360388] RDX: 1ffff1003a7a4c30 RSI: ffff8801d3cd68c8 RDI: ffff8801d3d26180 [ 33.367630] RBP: ffff8801d3067b60 R08: ffff8801d3cd68e8 R09: 0000000000000000 [ 33.374874] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d3d26058 [ 33.382120] R13: 0000000000000000 R14: ffff8801d3d26000 R15: ffff8801d3067c78 [ 33.389443] FS: 00007feb11040700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 33.397650] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 33.403509] CR2: 0000000000000080 CR3: 00000001d3a6f000 CR4: 00000000001606f0 [ 33.410758] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 33.418003] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 33.425249] Stack: [ 33.427379] 0000000000000201 ffffffff836ca141 ffff8801d3067ae0 ffffffff81237f0d [ 33.435373] ffff8801d3d26000 ffff8801d369f058 ffff8801d3d26058 ffff8801d369f050 [ 33.443375] ffff8801d369efb0 ffff8801d3d26020 0000000000000000 0000000000000000 [ 33.451368] Call Trace: [ 33.453937] [] ? l2tp_session_get+0x1d1/0x790 [ 33.460054] [] ? trace_hardirqs_on+0xd/0x10 [ 33.465996] [] pppol2tp_connect+0x10d7/0x18f0 [ 33.472112] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 33.478316] [] ? retint_kernel+0x2d/0x2d [ 33.483998] [] ? move_addr_to_kernel.part.13+0x35/0x110 [ 33.490981] [] ? __virt_addr_valid+0x27/0x1a0 [ 33.497101] [] ? __sanitizer_cov_trace_pc+0x4b/0x50 [ 33.503741] [] ? security_socket_connect+0x8f/0xc0 [ 33.510402] [] SYSC_connect+0x1b8/0x300 [ 33.516221] [] ? SYSC_bind+0x280/0x280 [ 33.521740] [] ? do_futex+0x17c0/0x17c0 [ 33.527338] [] ? retint_kernel+0x2d/0x2d [ 33.533023] [] ? perf_bp_event+0x180/0x180 [ 33.538881] [] SyS_connect+0x24/0x30 [ 33.544216] [] ? SyS_accept+0x30/0x30 [ 33.549637] [] do_syscall_64+0x1a6/0x490 [ 33.555384] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 33.562289] 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 [ 33.589094] RIP [] l2tp_session_create+0xc60/0x16f0 [ 33.595855] RSP [ 33.599452] CR2: 0000000000000080 [ 33.608126] ---[ end trace 8a7bf0a6b5c957be ]--- [ 33.613136] Kernel panic - not syncing: Fatal exception [ 33.613443] Dumping ftrace buffer: [ 33.613445] (ftrace buffer empty) [ 33.613447] Kernel Offset: disabled [ 33.629638] Rebooting in 86400 seconds..