[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.607009] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.570856] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 21.813690] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 22.819527] random: sshd: uninitialized urandom read (32 bytes read, 121 bits of entropy available) [ 35.314287] random: nonblocking pool is initialized Warning: Permanently added '10.128.10.2' (ECDSA) to the list of known hosts. executing program [ 42.811759] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff8330612a [ 42.811759] [ 42.822779] CPU: 0 PID: 3717 Comm: syzkaller730142 Not tainted 4.4.120-gd63fdf6 #28 [ 42.830543] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.839869] 0000000000000000 946cbe5dbea410b7 ffff8800ae437790 ffffffff81d0408d [ 42.847834] ffffffff83843960 ffff8800ae437868 00000000000005b4 ffff8801d1ae1264 [ 42.855790] 0000000000000040 ffff8800ae437858 ffffffff8141ab2a 0000000041b58ab3 [ 42.863836] Call Trace: [ 42.866397] [] dump_stack+0xc1/0x124 [ 42.871734] [] panic+0x1aa/0x388 [ 42.876717] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 42.883611] [] ? ip_mc_output+0x980/0x980 [ 42.889374] [] ? ip_fragment.constprop.49+0x200/0x200 [ 42.896531] [] ? ip6_xmit+0x16ba/0x1a70 [ 42.902120] [] ? __stack_chk_fail+0xa/0x30 [ 42.907973] [] ? ip6_xmit+0x16ba/0x1a70 [ 42.913566] [] __stack_chk_fail+0x22/0x30 [ 42.919336] [] ip6_xmit+0x16ba/0x1a70 [ 42.924754] [] ? kfree+0xfc/0x300 [ 42.929825] [] ? pskb_expand_head+0x28b/0x980 [ 42.935941] [] ? l2tp_xmit_skb+0xa5e/0xea0 [ 42.941796] [] ? ip6_finish_output2+0x1c60/0x1c60 [ 42.948258] [] ? __lock_is_held+0xa1/0xf0 [ 42.954026] [] ? ipv4_dst_check+0x111/0x160 [ 42.959964] [] ? __sk_dst_check+0x148/0x260 [ 42.965911] [] ? ip6_forward_finish+0x150/0x150 [ 42.972209] [] inet6_csk_xmit+0x246/0x480 [ 42.977974] [] ? inet6_csk_xmit+0x100/0x480 [ 42.983914] [] ? inet6_csk_update_pmtu+0x160/0x160 [ 42.990465] [] ? udp6_set_csum+0x336/0xa80 [ 42.996326] [] l2tp_xmit_skb+0xc2f/0xea0 [ 43.002013] [] pppol2tp_sendmsg+0x584/0x7f0 [ 43.007956] [] ? selinux_socket_sendmsg+0x3f/0x50 [ 43.014423] [] ? pppol2tp_release+0x310/0x310 [ 43.020536] [] sock_sendmsg+0xca/0x110 [ 43.026049] [] SYSC_sendto+0x2c8/0x340 [ 43.031554] [] ? SYSC_connect+0x310/0x310 [ 43.037323] [] ? lock_sock_nested+0xdc/0x120 [ 43.043366] [] ? ip6_datagram_connect+0x3a/0x50 [ 43.049656] [] ? inet_dgram_connect+0x172/0x1f0 [ 43.055943] [] ? SYSC_connect+0x212/0x310 [ 43.061710] [] ? retint_user+0x18/0x3c [ 43.067216] [] SyS_sendto+0x40/0x50 [ 43.072464] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 43.079447] Dumping ftrace buffer: [ 43.082997] (ftrace buffer empty) [ 43.086678] Kernel Offset: disabled [ 43.090291] Rebooting in 86400 seconds..