host-containers: chmod persistent storage directory after creation

[tjkirch]

Description of changes:

Tighten the permissions on the host-container-specific persistent storage directories, to reduce the chances that some other mistake could allow access to registration tokens, etc.

Testing done:

Before:

bash-5.0# ls -l /local/host-containers/
total 8
drwxr-xr-x. 3 root root 4096 Apr  5 23:19 admin
drwxrwxrwt. 2 root root 4096 Apr  5 23:18 control

After:

bash-5.0# ls -l /local/host-containers/
total 8
drwx------. 3 root root 4096 Apr  7 19:36 admin
drwx------. 2 root root 4096 Apr  7 19:36 control

Admin and control containers both still work as expected.

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[jpculp]

This looks good to me. Do we want to set the permissions explicitly for user-data as well?

[zmrow]

🦞