[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.299679] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 13.865159] random: sshd: uninitialized urandom read (32 bytes read) [ 14.354585] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 14.874690] random: sshd: uninitialized urandom read (32 bytes read) [ 15.004970] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.41' (ECDSA) to the list of known hosts. [ 20.500768] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 20:23:30 parsed 1 programs [ 22.395867] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 20:23:34 executed programs: 0 [ 24.259460] IPVS: Creating netns size=2536 id=1 [ 24.381402] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 24.394222] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 24.437391] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 24.448756] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 24.493047] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 24.504985] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 24.516952] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 24.537900] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 25.032127] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 25.056917] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 25.063652] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 25.070377] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 25.277155] hrtimer: interrupt took 18345 ns [ 25.361577] l2tp_core: tunl 4: sockfd_lookup(fd=7) returned -9 [ 25.575756] l2tp_core: tunl 4: sockfd_lookup(fd=7) returned -9 [ 25.590638] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 25.598866] IP: [] l2tp_session_create+0xc60/0x16f0 [ 25.605633] PGD 1d40ba067 [ 25.608284] PUD 1d4053067 PMD 0 [ 25.611759] [ 25.613379] Oops: 0002 [#1] PREEMPT SMP KASAN [ 25.617948] Dumping ftrace buffer: [ 25.621461] (ftrace buffer empty) [ 25.625151] Modules linked in: [ 25.628443] CPU: 1 PID: 4320 Comm: syz-executor0 Not tainted 4.9.123-g8dd3fc2 #31 [ 25.636041] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.645371] task: ffff8801d4736000 task.stack: ffff8801d3c00000 [ 25.651401] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 25.660622] RSP: 0018:ffff8801d3c07ab0 EFLAGS: 00010246 [ 25.666112] RAX: 0000000000000000 RBX: ffff8801d4670f00 RCX: 1ffff1003a8e6d1d [ 25.673371] RDX: 1ffff1003a796c80 RSI: ffff8801d47368c8 RDI: ffff8801d3cb6400 [ 25.680631] RBP: ffff8801d3c07b50 R08: ffff8801d47368e8 R09: 0000000000000000 [ 25.687892] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d3cb62d8 [ 25.695150] R13: 0000000000000000 R14: ffff8801d3cb6280 R15: ffff8801d3c07c68 [ 25.702411] FS: 0000000000000000(0000) GS:ffff8801db300000(0063) knlGS:00000000f77bdb40 [ 25.710626] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 25.716499] CR2: 0000000000000080 CR3: 00000001d512d000 CR4: 00000000001606f0 [ 25.723759] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 25.731047] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 25.738301] Stack: [ 25.740435] 0000000000000201 ffffffff836ca141 ffff8801d3c07ad0 ffffffff81237f0d [ 25.748466] ffff8801d3cb6280 ffff8801d4671058 ffff8801d3cb62d8 ffff8801d4671050 [ 25.756508] ffff8801d4670fb0 ffff8801d3cb62a0 0000000000000000 0000000000000000 [ 25.764530] Call Trace: [ 25.767107] [] ? l2tp_session_get+0x1d1/0x790 [ 25.773241] [] ? trace_hardirqs_on+0xd/0x10 [ 25.779203] [] pppol2tp_connect+0x10d7/0x18f0 [ 25.785340] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 25.791564] [] ? retint_kernel+0x2d/0x2d [ 25.797269] [] ? __virt_addr_valid+0xf7/0x1a0 [ 25.803404] [] ? __virt_addr_valid+0x10c/0x1a0 [ 25.809646] [] ? security_socket_connect+0x8f/0xc0 [ 25.816214] [] SYSC_connect+0x1b8/0x300 [ 25.821825] [] ? SYSC_bind+0x280/0x280 [ 25.827349] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 25.834350] [] ? retint_kernel+0x2d/0x2d [ 25.840047] [] SyS_connect+0x24/0x30 [ 25.845398] [] ? SyS_accept+0x30/0x30 [ 25.850839] [] do_fast_syscall_32+0x2f7/0x870 [ 25.856981] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.863640] [] entry_SYSENTER_compat+0x90/0xa2 [ 25.869851] 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 [ 25.897161] RIP [] l2tp_session_create+0xc60/0x16f0 [ 25.903956] RSP [ 25.907570] CR2: 0000000000000080 [ 25.914414] ---[ end trace 3c81b3481ff60db2 ]--- [ 25.919187] Kernel panic - not syncing: Fatal exception [ 25.924918] Dumping ftrace buffer: [ 25.928438] (ftrace buffer empty) [ 25.932122] Kernel Offset: disabled [ 25.935720] Rebooting in 86400 seconds..