[yocto] Overriding openssh sshd_config file in custom recipe

[Joshua Watt]

On Fri, 2017-10-20 at 15:24 +0300, Andreas Enbacka wrote:
> Hello,
>  
> I am trying to create a .bbappend file to customize the default
> sshd_config file as part of the default openssh package in Yocto
> Fido. In the custom file I attempt to disable root login access by
> setting the PermitRootLogin to No. However, after building and
> installing the image on the custom SMARC board, the content of the
> sshd_config file still enables login (PermitRootLogin Yes). I have
> checked the content of the installed rootfs before deploying to the
> board, and the content of the sshd_config file is correct (disables
> root login). What could be the cause of this? Is some other process
> modifying the content of the config file?

If "debug-tweaks" is in IMAGE_FEATURES, it will always allow root login
 with an empty password as a post processing step in the filesystem
image generation. See ssh_allow_empty_password in meta/classes/rootfs-
postcommands.bbclass

>  
> Best regards,
> Andreas Enbacka
>