Bad owner or permissions on /home/vncuser/.ssh/config

Today, I encountered such a problem when configuring ssh password-free login on a machine.
Bad owner or permissions on /home/vncuser/.ssh/config

Solution:

chmod 600 ~/.ssh/config

This is the first time I encountered this situation, before I only ~/.ssh/id_rsa.pubset permissions on it.

chmod 600 ~/.ssh/id_rsa.pub

Reference:
https://my.oschina.net/lovewinner/blog/1118876