[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.680112] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 14.626766] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 [ 14.923526] random: sshd: uninitialized urandom read (32 bytes read) syzkaller login: [ 15.693345] random: sshd: uninitialized urandom read (32 bytes read) [ 30.190097] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.6' (ECDSA) to the list of known hosts. [ 35.686709] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.622495] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 45.630750] IP: [] l2tp_session_create+0xc60/0x16f0 [ 45.637450] PGD 1d4f5b067 [ 45.640137] PUD 1c3da1067 PMD 0 [ 45.643635] [ 45.645257] Oops: 0002 [#1] PREEMPT SMP KASAN [ 45.649729] Dumping ftrace buffer: [ 45.653425] (ftrace buffer empty) [ 45.657113] Modules linked in: [ 45.660403] CPU: 0 PID: 8875 Comm: syz-executor892 Not tainted 4.9.111-g03c70fe #5 [ 45.668256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.677685] task: ffff8801d0728000 task.stack: ffff8801cf210000 [ 45.683800] RIP: 0010:[] [] l2tp_session_create+0xc60/0x16f0 [ 45.692924] RSP: 0018:ffff8801cf217ac0 EFLAGS: 00010246 [ 45.698354] RAX: 0000000000000000 RBX: ffff8801cfc70780 RCX: 1ffff1003a0e511d [ 45.705691] RDX: 1ffff10039ed60d0 RSI: ffff8801d07288c8 RDI: ffff8801cf6b0680 [ 45.712940] RBP: ffff8801cf217b60 R08: ffff8801d07288e8 R09: 0000000000000000 [ 45.720341] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801cf6b0558 [ 45.727602] R13: 0000000000000000 R14: ffff8801cf6b0500 R15: 0000000000000000 [ 45.734852] FS: 00007fc0eb908700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 45.743151] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 45.749215] CR2: 0000000000000080 CR3: 00000001da0f2000 CR4: 00000000001606f0 [ 45.756475] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 45.763897] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 45.771285] Stack: [ 45.773431] ffffffff836c0157 ffffffff836c11f1 ffff8801cdfa0848 0000000000000000 [ 45.781474] ffff8801cf6b0500 ffff8801cfc708d8 ffff8801cf6b0558 ffff8801cfc708d0 [ 45.789513] ffff8801cfc70830 ffff8801cf6b0520 ffff8801cdfa0000 0000000000000000 [ 45.797537] Call Trace: [ 45.800114] [] ? l2tp_session_create+0xed7/0x16f0 [ 45.806582] [] ? l2tp_session_get+0x1d1/0x790 [ 45.812712] [] pppol2tp_connect+0x10d7/0x18f0 [ 45.818843] [] ? pppol2tp_seq_show+0xc30/0xc30 [ 45.825068] [] ? security_socket_connect+0x8f/0xc0 [ 45.831732] [] SYSC_connect+0x1b8/0x300 [ 45.837341] [] ? vm_insert_mixed+0x200/0x200 [ 45.843463] [] ? SYSC_bind+0x280/0x280 [ 45.849120] [] ? up_read+0x1a/0x40 [ 45.854294] [] ? __do_page_fault+0x183/0xd50 [ 45.860346] [] SyS_connect+0x24/0x30 [ 45.865700] [] ? SyS_accept+0x30/0x30 [ 45.871138] [] do_syscall_64+0x1a6/0x490 [ 45.876831] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 45.883735] 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 [ 45.911425] RIP [] l2tp_session_create+0xc60/0x16f0 [ 45.918207] RSP [ 45.921804] CR2: 0000000000000080 [ 45.925951] ---[ end trace 7cd0db5a47ff901b ]--- [ 45.930752] Kernel panic - not syncing: Fatal exception [ 45.932402] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 45.932415] IP: [] l2tp_session_free+0x11c/0x200 [ 45.932419] PGD 1d0628067 [ 45.932421] PUD 1d080c067 [ 45.932422] PMD 0 [ 45.932422] [ 45.932427] Oops: 0002 [#2] PREEMPT SMP KASAN [ 45.932432] Dumping ftrace buffer: [ 45.932435] (ftrace buffer empty) [ 45.932438] Modules linked in: [ 45.932445] CPU: 1 PID: 8861 Comm: syz-executor892 Tainted: G D 4.9.111-g03c70fe #5 [ 45.932448] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.932451] task: ffff8801cf6f6000 task.stack: ffff8801cf660000 [ 45.932457] RIP: 0010:[] [] l2tp_session_free+0x11c/0x200 [ 45.932459] RSP: 0018:ffff8801cf667ca0 EFLAGS: 00010246 [ 45.932462] RAX: dffffc0000000000 RBX: ffff8801cf6b0780 RCX: 0000000000000001 [ 45.932464] RDX: 1ffff10039ed60d0 RSI: ffffffff836bba41 RDI: ffff8801cf6b0680 [ 45.932467] RBP: ffff8801cf667cc0 R08: 0000000000000001 R09: 0000000000000000 [ 45.932469] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801cf6b0500 [ 45.932472] R13: ffff8801cf6b0788 R14: 0000000000000000 R15: ffffffff83012be0 [ 45.932476] FS: 00007fc0eb908700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 45.932478] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 45.932481] CR2: 0000000000000080 CR3: 00000001cf411000 CR4: 00000000001606f0 [ 45.932486] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 45.932488] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 45.932489] Stack: [ 45.932495] ffff8801cf822200 ffff8801cf6b0780 ffff8801cf8225d0 ffff8801cf8224d8 [ 45.932501] ffff8801cf667ce8 ffffffff836c3352 ffff8801cf822640 ffff8801cf822200 [ 45.932506] ffffffff836c3280 ffff8801cf667d20 ffffffff83020095 ffff8801cf822640 [ 45.932506] Call Trace: [ 45.932514] [] pppol2tp_session_destruct+0xd2/0x110 [ 45.932518] [] ? pppol2tp_seq_start+0x4e0/0x4e0 [ 45.932525] [] __sk_destruct+0x55/0x590 [ 45.932531] [] ? sock_release+0x1c0/0x1c0 [ 45.932535] [] sk_destruct+0x63/0x80 [ 45.932538] [] __sk_free+0x4f/0x220 [ 45.932542] [] sk_free+0x2b/0x40 [ 45.932546] [] pppol2tp_release+0x239/0x2e0 [ 45.932550] [] sock_release+0x96/0x1c0 [ 45.932553] [] sock_close+0x16/0x20 [ 45.932561] [] __fput+0x263/0x700 [ 45.932565] [] ____fput+0x15/0x20 [ 45.932587] [] task_work_run+0x10c/0x180 [ 45.932594] [] exit_to_usermode_loop+0xfc/0x120 [ 45.932598] [] do_syscall_64+0x364/0x490 [ 45.932605] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 45.932665] Code: 49 8d bc 24 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 c6 00 00 00 4d 8b b4 24 80 01 00 00 41 ff 8e 80 00 00 00 74 69 e8 95 2f ca fd 4c 89 ea 48 b8 00 [ 45.932669] RIP [] l2tp_session_free+0x11c/0x200 [ 45.932671] RSP [ 45.932672] CR2: 0000000000000080 [ 45.932675] ---[ end trace 7cd0db5a47ff901c ]--- [ 47.353303] Shutting down cpus with NMI [ 47.357838] Dumping ftrace buffer: [ 47.361360] (ftrace buffer empty) [ 47.365045] Kernel Offset: disabled [ 47.368646] Rebooting in 86400 seconds..