[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 12.742128] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.621330] random: sshd: uninitialized urandom read (32 bytes read) [ 17.936270] random: sshd: uninitialized urandom read (32 bytes read) [ 18.424726] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.36' (ECDSA) to the list of known hosts. [ 24.104259] urandom_read: 1 callbacks suppressed [ 24.104263] random: sshd: uninitialized urandom read (32 bytes read) 2018/08/22 05:17:40 parsed 1 programs [ 25.474897] random: cc1: uninitialized urandom read (8 bytes read) 2018/08/22 05:17:42 executed programs: 0 [ 26.812924] IPVS: Creating netns size=2536 id=1 [ 26.940425] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 26.952677] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 26.997541] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 27.009284] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 27.053897] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 27.065420] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 27.077775] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 27.093872] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 27.601588] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 27.627528] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 27.633774] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 27.641496] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 27.832120] hrtimer: interrupt took 36165 ns [ 27.993556] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.126371] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.260464] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.303537] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.407017] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.442044] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.483180] l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9 [ 28.516849] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 28.525100] IP: [] l2tp_session_create+0xc60/0x16f0 [ 28.531787] PGD 1cc80d067 [ 28.534540] PUD 1cccca067 PMD 0 [ 28.538051] [ 28.539679] Oops: 0002 [#1] PREEMPT SMP KASAN [ 28.544157] Dumping ftrace buffer: [ 28.547672] (ftrace buffer empty) [ 28.551391] Modules linked in: [ 28.554789] CPU: 0 PID: 4464 Comm: syz-executor0 Not tainted 4.9.122-g54068d6 #78 [ 28.562393] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.571846] task: ffff8801d51a0000 task.stack: ffff8801d51a8000 [ 28.577962] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 28.587096] RSP: 0018:ffff8801d51afac0 EFLAGS: 00010246 [ 28.592546] RAX: 0000000000000000 RBX: ffff8801d40c0f00 RCX: 1ffff1003aa3411d [ 28.599800] RDX: 1ffff1003a7e36b0 RSI: ffff8801d51a08c8 RDI: ffff8801d3f1b580 [ 28.607062] RBP: ffff8801d51afb60 R08: ffff8801d51a08e8 R09: 0000000000000000 [ 28.614415] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d3f1b458 [ 28.621726] R13: 0000000000000000 R14: ffff8801d3f1b400 R15: ffff8801d51afc78 [ 28.628982] FS: 00007efcc2fda700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 28.637183] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.643048] CR2: 0000000000000080 CR3: 00000001d803e000 CR4: 00000000001606f0 [ 28.650298] Stack: [ 28.652427] 0000000000000201 ffffffff836c9151 ffff8801d51afae0 ffffffff81237ecd [ 28.660432] ffff8801d3f1b400 ffff8801d40c1058 ffff8801d3f1b458 ffff8801d40c1050 [ 28.668441] ffff8801d40c0fb0 ffff8801d3f1b420 0000000000000000 0000000000000000 [ 28.676451] Call Trace: [ 28.679019] [] ? l2tp_session_get+0x1d1/0x790 [ 28.685158] [] ? trace_hardirqs_on+0xd/0x10 [ 28.691110] [] pppol2tp_connect+0x10d7/0x18f0 [ 28.697240] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 28.703456] [] ? security_socket_connect+0x8f/0xc0 [ 28.710019] [] SYSC_connect+0x1b8/0x300 [ 28.715629] [] ? SYSC_bind+0x280/0x280 [ 28.721162] [] ? do_futex+0x17c0/0x17c0 [ 28.726770] [] ? move_addr_to_kernel+0x50/0x50 [ 28.733085] [] SyS_connect+0x24/0x30 [ 28.738438] [] ? SyS_accept+0x30/0x30 [ 28.743869] [] do_syscall_64+0x1a6/0x490 [ 28.749583] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 28.756485] 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 [ 28.783542] RIP [] l2tp_session_create+0xc60/0x16f0 [ 28.790311] RSP [ 28.793911] CR2: 0000000000000080 [ 28.798188] ---[ end trace 25fe6281f386b3d8 ]--- [ 28.802964] Kernel panic - not syncing: Fatal exception [ 28.808617] Dumping ftrace buffer: [ 28.812136] (ftrace buffer empty) [ 28.815822] Kernel Offset: disabled [ 28.819420] Rebooting in 86400 seconds..