[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.620719] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 15.544231] random: sshd: uninitialized urandom read (32 bytes read) [ 16.066258] random: sshd: uninitialized urandom read (32 bytes read) [ 16.629536] random: sshd: uninitialized urandom read (32 bytes read) [ 16.772400] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.35' (ECDSA) to the list of known hosts. [ 22.257603] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 18:34:09 parsed 1 programs [ 23.250737] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 18:34:11 executed programs: 0 [ 24.625388] IPVS: Creating netns size=2536 id=1 [ 24.748016] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 24.759028] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 24.800951] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 24.812094] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 24.855608] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 24.866797] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 24.878662] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 24.899123] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 25.388650] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 25.412774] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 25.419353] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 25.426866] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 25.615981] hrtimer: interrupt took 18871 ns [ 25.731168] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 25.739692] IP: [] l2tp_session_create+0xc60/0x16f0 [ 25.746390] PGD 1da2bd067 [ 25.749140] PUD 1d6e38067 PMD 0 [ 25.752651] [ 25.754277] Oops: 0002 [#1] PREEMPT SMP KASAN [ 25.758746] Dumping ftrace buffer: [ 25.762267] (ftrace buffer empty) [ 25.765960] Modules linked in: [ 25.769356] CPU: 0 PID: 4241 Comm: syz-executor0 Not tainted 4.9.123-g8dd3fc2 #79 [ 25.776961] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.786292] task: ffff8801d55c9800 task.stack: ffff8801d52c0000 [ 25.792326] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 25.801449] RSP: 0018:ffff8801d52c7ac0 EFLAGS: 00010246 [ 25.806972] RAX: 0000000000000000 RBX: ffff8801da245680 RCX: 1ffff1003aab941d [ 25.814224] RDX: 1ffff1003b448a60 RSI: ffff8801d55ca0c8 RDI: ffff8801da245300 [ 25.821472] RBP: ffff8801d52c7b60 R08: ffff8801d55ca0e8 R09: 0000000000000000 [ 25.828719] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801da2451d8 [ 25.835966] R13: 0000000000000000 R14: ffff8801da245180 R15: ffff8801d52c7c78 [ 25.843306] FS: 00007fa357837700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 25.851517] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 25.857472] CR2: 0000000000000080 CR3: 00000001d6ded000 CR4: 00000000001606f0 [ 25.864729] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 25.871978] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 25.879222] Stack: [ 25.881348] 0000000000000201 ffffffff836ca141 ffff8801d52c7ae0 ffffffff81237f0d [ 25.889360] ffff8801da245180 ffff8801da2457d8 ffff8801da2451d8 ffff8801da2457d0 [ 25.897378] ffff8801da245730 ffff8801da2451a0 0000000000000000 0000000000000000 [ 25.905391] Call Trace: [ 25.908036] [] ? l2tp_session_get+0x1d1/0x790 [ 25.914167] [] ? trace_hardirqs_on+0xd/0x10 [ 25.920118] [] pppol2tp_connect+0x10d7/0x18f0 [ 25.926243] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 25.932458] [] ? check_preemption_disabled+0x3b/0x170 [ 25.939276] [] ? retint_kernel+0x2d/0x2d [ 25.944965] [] ? security_socket_connect+0x8f/0xc0 [ 25.951538] [] SYSC_connect+0x1b8/0x300 [ 25.957137] [] ? SYSC_bind+0x280/0x280 [ 25.962757] [] ? do_futex+0x17c0/0x17c0 [ 25.968364] [] ? move_addr_to_kernel+0x50/0x50 [ 25.974594] [] SyS_connect+0x24/0x30 [ 25.979932] [] ? SyS_accept+0x30/0x30 [ 25.985362] [] do_syscall_64+0x1a6/0x490 [ 25.991061] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 25.997960] 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 [ 26.024912] RIP [] l2tp_session_create+0xc60/0x16f0 [ 26.031741] RSP [ 26.035339] CR2: 0000000000000080 [ 26.039868] ---[ end trace d7396ad62fc6ca0e ]--- [ 26.044746] Kernel panic - not syncing: Fatal exception [ 26.050444] Dumping ftrace buffer: [ 26.053964] (ftrace buffer empty) [ 26.057648] Kernel Offset: disabled [ 26.061250] Rebooting in 86400 seconds..