[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   20.144653] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.
[   21.321473] random: sshd: uninitialized urandom read (32 bytes read)

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   21.739193] random: sshd: uninitialized urandom read (32 bytes read)
[   22.476914] random: sshd: uninitialized urandom read (32 bytes read)
[   22.637403] random: sshd: uninitialized urandom read (32 bytes read)
Warning: Permanently added '10.128.0.55' (ECDSA) to the list of known hosts.
[   28.111969] random: sshd: uninitialized urandom read (32 bytes read)
executing program
[   28.203581] WARNING: CPU: 0 PID: 4501 at include/net/sock.h:644 smc_unhash_sk+0x345/0x4a0
[   28.211978] Kernel panic - not syncing: panic_on_warn set ...
[   28.211978] 
[   28.219330] CPU: 0 PID: 4501 Comm: syz-executor949 Not tainted 4.17.0-rc3+ #37
[   28.226666] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   28.235998] Call Trace:
[   28.238575]  dump_stack+0x1b9/0x294
[   28.242183]  ? dump_stack_print_info.cold.2+0x52/0x52
[   28.247358]  ? smc_unhash_sk+0x320/0x4a0
[   28.251399]  panic+0x22f/0x4de
[   28.254572]  ? add_taint.cold.5+0x16/0x16
[   28.258703]  ? __warn.cold.8+0x148/0x1b3
[   28.262742]  ? __warn.cold.8+0x117/0x1b3
[   28.266783]  ? smc_unhash_sk+0x345/0x4a0
[   28.270828]  __warn.cold.8+0x163/0x1b3
[   28.274696]  ? smc_unhash_sk+0x345/0x4a0
[   28.278737]  report_bug+0x252/0x2d0
[   28.282386]  do_error_trap+0x1de/0x490
[   28.286255]  ? graph_lock+0x170/0x170
[   28.290044]  ? math_error+0x420/0x420
[   28.293836]  ? lock_acquire+0x1dc/0x520
[   28.297797]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   28.302620]  do_invalid_op+0x1b/0x20
[   28.306313]  invalid_op+0x14/0x20
[   28.309746] RIP: 0010:smc_unhash_sk+0x345/0x4a0
[   28.314391] RSP: 0018:ffff8801ab4a7488 EFLAGS: 00010293
[   28.319735] RAX: ffff8801d906a680 RBX: ffff8801ab5da7c0 RCX: ffffffff873f756e
[   28.326985] RDX: 0000000000000000 RSI: ffffffff873f7625 RDI: 0000000000000005
[   28.334237] RBP: ffff8801ab4a7570 R08: ffff8801d906a680 R09: ffffed00356bb508
[   28.341486] R10: ffffed00356bb508 R11: ffff8801ab5da843 R12: 1ffff10035694e95
[   28.348736] R13: ffff8801ab4a7548 R14: ffffffff8970b1e0 R15: ffff8801ab5da840
[   28.356002]  ? smc_unhash_sk+0x28e/0x4a0
[   28.360052]  ? smc_unhash_sk+0x345/0x4a0
[   28.364096]  ? smc_unhash_sk+0x345/0x4a0
[   28.368138]  ? smc_rx_data_available+0x100/0x100
[   28.373042]  ? release_sock+0x1e2/0x2b0
[   28.377029]  ? __local_bh_enable_ip+0x161/0x230
[   28.381685]  ? __release_sock+0x3a0/0x3a0
[   28.385814]  ? smc_release+0x269/0x610
[   28.389683]  ? trace_hardirqs_on+0xd/0x10
[   28.393831]  ? __local_bh_enable_ip+0x161/0x230
[   28.398489]  smc_release+0x36e/0x610
[   28.402190]  sock_release+0x96/0x1b0
[   28.405884]  ? sock_alloc_file+0x4e0/0x4e0
[   28.410100]  sock_close+0x16/0x20
[   28.413544]  __fput+0x34d/0x890
[   28.416816]  ? fput+0x1a0/0x1a0
[   28.420078]  ? _raw_spin_unlock_irq+0x27/0x70
[   28.424566]  ____fput+0x15/0x20
[   28.427827]  task_work_run+0x1e4/0x290
[   28.431702]  ? task_work_cancel+0x240/0x240
[   28.436009]  ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[   28.441535]  ? switch_task_namespaces+0xa2/0xd0
[   28.446185]  do_exit+0x1aee/0x2730
[   28.449708]  ? _raw_spin_unlock_bh+0x30/0x40
[   28.454103]  ? mm_update_next_owner+0x980/0x980
[   28.458759]  ? ___sys_sendmsg+0x31a/0x940
[   28.462898]  ? rcu_read_lock_sched_held+0x108/0x120
[   28.467895]  ? kfree+0x1e9/0x260
[   28.471244]  ? ___sys_sendmsg+0x31f/0x940
[   28.475375]  ? copy_msghdr_from_user+0x560/0x560
[   28.480113]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   28.485108]  ? graph_lock+0x170/0x170
[   28.488892]  ? pud_val+0x80/0xf0
[   28.492246]  ? __handle_mm_fault+0x93a/0x4310
[   28.496725]  ? vm_insert_mixed_mkwrite+0x40/0x40
[   28.501459]  ? graph_lock+0x170/0x170
[   28.505253]  ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[   28.510778]  ? sockfd_lookup_light+0xc5/0x160
[   28.515259]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[   28.520780]  ? __sys_sendmmsg+0x4b3/0x6f0
[   28.524913]  ? __ia32_sys_sendmsg+0xb0/0xb0
[   28.529218]  ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20
[   28.534742]  ? __handle_mm_fault+0x4310/0x4310
[   28.539314]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[   28.544832]  ? __do_page_fault+0x441/0xe40
[   28.549054]  do_group_exit+0x16f/0x430
[   28.552925]  ? mm_fault_error+0x380/0x380
[   28.557055]  ? __ia32_sys_exit+0x50/0x50
[   28.561111]  ? do_syscall_64+0x92/0x800
[   28.565067]  __x64_sys_exit_group+0x3e/0x50
[   28.569371]  do_syscall_64+0x1b1/0x800
[   28.573242]  ? syscall_slow_exit_work+0x4f0/0x4f0
[   28.578072]  ? syscall_return_slowpath+0x5c0/0x5c0
[   28.582984]  ? syscall_return_slowpath+0x30f/0x5c0
[   28.587898]  ? entry_SYSCALL_64_after_hwframe+0x59/0xbe
[   28.593249]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   28.598088]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   28.603257] RIP: 0033:0x43f108
[   28.606427] RSP: 002b:00007fffba792d08 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[   28.614117] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f108
[   28.621366] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
[   28.628616] RBP: 00000000004beaa0 R08: 00000000000000e7 R09: ffffffffffffffd0
[   28.635865] R10: 0000000024000005 R11: 0000000000000246 R12: 0000000000000001
[   28.643115] R13: 00000000006cc160 R14: 0000000000000000 R15: 0000000000000000
[   28.650975] Dumping ftrace buffer:
[   28.654602]    (ftrace buffer empty)
[   28.658294] Kernel Offset: disabled
[   28.661902] Rebooting in 86400 seconds..