sunrpc: infinite unkillable console spam in xs_tcp_setup_socket

From: Dmitry Vyukov
Date: Mon Nov 20 2017 - 08:02:56 EST


Hello,

The following program triggers infinite stream of the following output
on console. The program is unkillable and this effectively brings the
machine down:


** 16 printk messages dropped ** [12875.022917] xs_tcp_setup_socket:
connect returned unhandled error -113
** 17 printk messages dropped ** [12875.024832] xs_tcp_setup_socket:
connect returned unhandled error -113
** 17 printk messages dropped ** [12875.026765] xs_tcp_setup_socket:
connect returned unhandled error -113
** 17 printk messages dropped ** [12875.028729] xs_tcp_setup_socket:
connect returned unhandled error -113
** 17 printk messages dropped ** [12875.030648] xs_tcp_setup_socket:
connect returned unhandled error -113
** 15 printk messages dropped ** [12875.032360] xs_tcp_setup_socket:
connect returned unhandled error -113
** 16 printk messages dropped ** [12875.034197] xs_tcp_setup_socket:
connect returned unhandled error -113
** 16 printk messages dropped ** [12875.035988] xs_tcp_setup_socket:
connect returned unhandled error -113
** 15 printk messages dropped ** [12875.037718] xs_tcp_setup_socket:
connect returned unhandled error -113
** 16 printk messages dropped ** [12875.039553] xs_tcp_setup_socket:
connect returned unhandled error -113
** 16 printk messages dropped ** [12875.041392] xs_tcp_setup_socket:
connect returned unhandled error -113


Program:
https://gist.github.com/dvyukov/629543c9abc19576fec66ce8fae130c7

On upstream commit c8a0739b185d11d6e2ca7ad9f5835841d1cfc765 (Nov 19).
Config is attached.

Found by syzkaller fuzzer.

Thanks.

Attachment: .config
Description: Binary data