[....] 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[ 13.134681] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.749911] random: sshd: uninitialized urandom read (32 bytes read) [ 18.114552] random: sshd: uninitialized urandom read (32 bytes read) [ 18.601036] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.20' (ECDSA) to the list of known hosts. [ 24.307661] urandom_read: 1 callbacks suppressed [ 24.307664] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program [ 24.531954] ------------[ cut here ]------------ [ 24.536731] WARNING: CPU: 1 PID: 0 at net/ipv4/af_inet.c:167 inet_sock_destruct+0x598/0x760 [ 24.545240] Kernel panic - not syncing: panic_on_warn set ... [ 24.545240] [ 24.552637] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.119-g9dc978d #23 [ 24.559741] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.569122] ffff8801db307cc0 ffffffff81eb4be9 ffffffff83c48980 00000000ffffffff [ 24.577143] 0000000000000000 0000000000000001 00000000000000a7 ffff8801db307d80 [ 24.585150] ffffffff81421c95 0000000041b58ab3 ffffffff843bc020 ffffffff81421ad6 [ 24.593182] Call Trace: [ 24.595755] [ 24.597797] [] dump_stack+0xc1/0x128 [ 24.603157] [] panic+0x1bf/0x3bc [ 24.608153] [] ? add_taint.cold.6+0x16/0x16 [ 24.614114] [] ? __warn.cold.9+0xa6/0x17f [ 24.619951] [] ? inet_sock_destruct+0x598/0x760 [ 24.626255] [] __warn.cold.9+0xc1/0x17f [ 24.631860] [] ? l2tp_tunnel_closeall+0x2af/0x350 [ 24.638344] [] warn_slowpath_null+0x2c/0x40 [ 24.644299] [] inet_sock_destruct+0x598/0x760 [ 24.650422] [] ? ipv4_mib_init_net+0x570/0x570 [ 24.656753] [] l2tp_tunnel_destruct+0x339/0x590 [ 24.663173] [] ? l2tp_tunnel_destruct+0x1aa/0x590 [ 24.669674] [] ? l2tp_tunnel_del_work+0x470/0x470 [ 24.676271] [] __sk_destruct+0x55/0x590 [ 24.681890] [] rcu_process_callbacks+0x8ae/0x12b0 [ 24.688386] [] ? rcu_process_callbacks+0x98e/0x12b0 [ 24.695031] [] ? sock_set_timeout+0x210/0x210 [ 24.701170] [] __do_softirq+0x20b/0x937 [ 24.706772] [] irq_exit+0x147/0x190 [ 24.712136] [] smp_apic_timer_interrupt+0x81/0xa0 [ 24.718680] [] apic_timer_interrupt+0xa0/0xb0 [ 24.724804] [ 24.726850] [] ? native_safe_halt+0x6/0x10 [ 24.732733] [] ? trace_hardirqs_on+0xd/0x10 [ 24.738688] [] default_idle+0x55/0x360 [ 24.744213] [] arch_cpu_idle+0x10/0x20 [ 24.749733] [] default_idle_call+0x45/0x60 [ 24.755598] [] cpu_startup_entry+0x2b5/0x380 [ 24.761637] [] ? cpu_in_idle+0x20/0x20 [ 24.767154] [] start_secondary+0x328/0x400 [ 24.773020] [] ? set_cpu_sibling_map+0x1300/0x1300 [ 24.779980] Dumping ftrace buffer: [ 24.783573] (ftrace buffer empty) [ 24.787271] Kernel Offset: disabled [ 24.790885] Rebooting in 86400 seconds..