Re: [PATCH v11 16/48] richacl: Automatic Inheritance

Andy Lutomirski
2015-10-16T16:00:36Z

On Fri, Oct 16, 2015 at 8:17 AM, Andreas Gruenbacher
<agruenba@redhat.com> wrote:
> Automatic Inheritance (AI) allows changes to the acl of a directory to
> propagate down to children.
>
> This is mostly implemented in user space: when a process changes the
> permissions of a directory and Automatic Inheritance is enabled for that
> directory, the process must propagate those changes to all children,
> recursively.
>
> The kernel enables this by keeping track of which permissions have been
> inherited at create time. In addition, it makes sure that permission
> propagation is turned off when the permissions are set explicitly (for
> example, upon create or chmod).
>
> Automatic Inheritance works as follows:
>
> - When the RICHACL_AUTO_INHERIT flag in the acl of a file or directory
> is not set, the file or directory is not affected by AI.
>
> - When the RICHACL_AUTO_INHERIT flag in the acl of a directory is set
> and a file or subdirectory is created in that directory, the
> inherited acl will have the RICHACL_AUTO_INHERIT flag set, and all
> inherited aces will have the RICHACE_INHERITED_ACE flag set. This
> allows user space to distinguish between aces which have been
> inherited and aces which have been explicitly added.

What if the file or subdirectory that's created in that directory is a
hard link?

--Andy