[....] Starting file context maintaining daemon:[ 17.541200] random: sshd: uninitialized urandom read (32 bytes read, 31 bits of entropy available) restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.212461] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 22.741395] random: sshd: uninitialized urandom read (32 bytes read, 38 bits of entropy available) [ 23.585806] random: sshd: uninitialized urandom read (32 bytes read, 96 bits of entropy available) [ 23.755087] random: sshd: uninitialized urandom read (32 bytes read, 101 bits of entropy available) Warning: Permanently added '10.128.0.29' (ECDSA) to the list of known hosts. [ 29.154842] random: sshd: uninitialized urandom read (32 bytes read, 108 bits of entropy available) executing program [ 29.263136] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff8330346e [ 29.263136] [ 29.274184] CPU: 0 PID: 3327 Comm: syzkaller643309 Not tainted 4.4.113-ge70c132 #27 [ 29.281963] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.291289] 0000000000000000 0aa2b408d8afe6b7 ffff8800b46275d8 ffffffff81d0278d [ 29.299274] ffffffff838437c0 ffff8800b46276b0 00000000000005b4 ffff8801d5740064 [ 29.307258] 0000000000000040 ffff8800b46276a0 ffffffff81419b6a 0000000041b58ab3 [ 29.315257] Call Trace: [ 29.317820] [] dump_stack+0xc1/0x124 [ 29.323160] [] panic+0x1aa/0x388 [ 29.328151] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 29.335053] [] ? ip_mc_output+0x980/0x980 [ 29.340822] [] ? ip_fragment.constprop.49+0x200/0x200 [ 29.347636] [] ? ip6_xmit+0x170e/0x1ad0 [ 29.353247] [] ? __stack_chk_fail+0xa/0x30 [ 29.359102] [] ? ip6_xmit+0x170e/0x1ad0 [ 29.364698] [] __stack_chk_fail+0x22/0x30 [ 29.370467] [] ip6_xmit+0x170e/0x1ad0 [ 29.375904] [] ? save_trace+0xe0/0x270 [ 29.381423] [] ? __alloc_pages_direct_compact+0x250/0x250 [ 29.388584] [] ? ip6_finish_output2+0x1c60/0x1c60 [ 29.395049] [] ? __lock_is_held+0xa1/0xf0 [ 29.400821] [] ? ipv4_dst_check+0x111/0x160 [ 29.406768] [] ? ip6_forward_finish+0x150/0x150 [ 29.413062] [] inet6_csk_xmit+0x246/0x480 [ 29.418830] [] ? inet6_csk_xmit+0x100/0x480 [ 29.424773] [] ? inet6_csk_update_pmtu+0x160/0x160 [ 29.431327] [] ? udp6_set_csum+0x336/0xa80 [ 29.437186] [] l2tp_xmit_skb+0xc2f/0xea0 [ 29.442870] [] pppol2tp_sendmsg+0x584/0x7f0 [ 29.449717] [] ? selinux_socket_sendmsg+0x3f/0x50 [ 29.456199] [] ? pppol2tp_release+0x310/0x310 [ 29.462319] [] sock_sendmsg+0xca/0x110 [ 29.467824] [] ___sys_sendmsg+0x6c1/0x7c0 [ 29.473599] [] ? copy_msghdr_from_user+0x550/0x550 [ 29.480152] [] ? __alloc_pages_direct_compact+0x250/0x250 [ 29.487320] [] ? __lock_is_held+0xa1/0xf0 [ 29.493094] [] ? check_preemption_disabled+0x3b/0x200 [ 29.499907] [] ? do_huge_pmd_anonymous_page+0x549/0xa10 [ 29.506894] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 29.513619] [] ? __fget_light+0xa1/0x1e0 [ 29.519300] [] ? __fdget+0x18/0x20 [ 29.524475] [] ? sockfd_lookup_light+0x118/0x160 [ 29.530851] [] __sys_sendmsg+0xd3/0x190 [ 29.536446] [] ? SyS_shutdown+0x1b0/0x1b0 [ 29.542222] [] ? __do_page_fault+0x380/0xa00 [ 29.548253] [] compat_SyS_sendmsg+0x2a/0x40 [ 29.554195] [] ? compat_SyS_getsockopt+0x2a0/0x2a0 [ 29.560762] [] do_fast_syscall_32+0x314/0x890 [ 29.566884] [] sysenter_flags_fixed+0xd/0x17 [ 29.573513] Dumping ftrace buffer: [ 29.577096] (ftrace buffer empty) [ 29.580780] Kernel Offset: disabled [ 29.584395] Rebooting in 86400 seconds..