[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   22.349429] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   27.879276] random: sshd: uninitialized urandom read (32 bytes read, 42 bits of entropy available)
[   28.183390] random: sshd: uninitialized urandom read (32 bytes read, 42 bits of entropy available)
[   28.895381] random: sshd: uninitialized urandom read (32 bytes read, 71 bits of entropy available)
[   29.066907] random: sshd: uninitialized urandom read (32 bytes read, 73 bits of entropy available)
Warning: Permanently added '10.128.0.32' (ECDSA) to the list of known hosts.
[   34.503943] random: sshd: uninitialized urandom read (32 bytes read, 79 bits of entropy available)
executing program
[   34.592780] BUG: using __this_cpu_add() in preemptible [00000000] code: syz-executor670/3823
[   34.601373] caller is __this_cpu_preempt_check+0x1c/0x20
[   34.607042] CPU: 1 PID: 3823 Comm: syz-executor670 Not tainted 4.4.147-ga5fc665 #16
[   34.614826] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   34.624155]  0000000000000000 917c1939ec9a7fcb ffff8801d81d7790 ffffffff81e12a4d
[   34.632143]  0000000000000001 ffffffff83c153c0 ffffffff83f0d300 ffff8801d2c14800
[   34.640238]  0000000000000003 ffff8801d81d77d0 ffffffff81ebc2f3 ffff8801ce3787fc
[   34.648260] Call Trace:
[   34.650825]  [<ffffffff81e12a4d>] dump_stack+0xc1/0x124
[   34.656169]  [<ffffffff81ebc2f3>] check_preemption_disabled.cold.0+0x7f/0x8b
[   34.663337]  [<ffffffff81e726ec>] __this_cpu_preempt_check+0x1c/0x20
[   34.669803]  [<ffffffff83259c1a>] tcp_try_coalesce+0x22a/0x4c0
[   34.675747]  [<ffffffff832599f0>] ? tcp_parse_options+0x970/0x970
[   34.681952]  [<ffffffff83260817>] tcp_queue_rcv+0x127/0x6f0
[   34.687752]  [<ffffffff83278ab6>] tcp_send_rcvq+0x3a6/0x470
[   34.693439]  [<ffffffff83278710>] ? tcp_rcv_established+0x1fe0/0x1fe0
[   34.699993]  [<ffffffff8113fc00>] ? __local_bh_enable_ip+0x40/0xd0
[   34.706303]  [<ffffffff81230b4b>] ? trace_hardirqs_on_caller+0x38b/0x590
[   34.713245]  [<ffffffff82f2c0e0>] ? lock_sock_nested+0x90/0x120
[   34.719284]  [<ffffffff81230d5d>] ? trace_hardirqs_on+0xd/0x10
[   34.725239]  [<ffffffff8113fc2a>] ? __local_bh_enable_ip+0x6a/0xd0
[   34.731534]  [<ffffffff8325019c>] tcp_sendmsg+0x23ec/0x2b10
[   34.737224]  [<ffffffff81c7287f>] ? sock_has_perm+0x29f/0x400
[   34.743151]  [<ffffffff8324ddb0>] ? tcp_sendpage+0x17c0/0x17c0
[   34.749104]  [<ffffffff83306bc3>] ? inet_sendmsg+0x143/0x4d0
[   34.754878]  [<ffffffff83306c83>] inet_sendmsg+0x203/0x4d0
[   34.760482]  [<ffffffff83306af3>] ? inet_sendmsg+0x73/0x4d0
[   34.766173]  [<ffffffff83306a80>] ? inet_recvmsg+0x4c0/0x4c0
[   34.771945]  [<ffffffff82f2391c>] sock_sendmsg+0xcc/0x110
[   34.777464]  [<ffffffff82f245fc>] SYSC_sendto+0x21c/0x370
[   34.783062]  [<ffffffff82f243e0>] ? SYSC_connect+0x300/0x300
[   34.788840]  [<ffffffff82f277c6>] ? __sys_sendmmsg+0x23