On 4/10/2017 9:43 PM, Kees Cook wrote:

On Mon, Apr 10, 2017 at 1:00 PM, Djalal Harouni [off-list ref] wrote:

quoted

On Mon, Apr 10, 2017 at 9:26 PM, Casey Schaufler [off-list ref] wrote:

quoted

I think that would be the prudent approach. There is still
the possibility that blob sharing (or full stacking, if you
prefer) won't be accepted any time soon.

Ok Casey! I will wait for more feedback, and if other maintainers do
not object, I will convert it back to rhashtables in next iterations
making sure that it should be simple to convert later to a blob
sharing mechanism.

Would it be possible just to add a single field to task_struct if this
LSM is built in? I feel like rhashtables is a huge overhead when a
single field is all that's needed.

Special casing the task_struct based on which modules
are compiled in would work, but I'm under the impression
that there's a strong desire to keep to one pointer for
security module information in the major structures.

The code for generalizing shared blobs isn't that hard,
and y'all have seen it many times. It would be perfectly
safe to convert the task, cred, inode and such blobs to
be infrastructure managed right now. That wouldn't mean
that all the stacking issues (e.g. audit and networking)
would be addressed, or that all combinations of modules
would work (i.e. no SELinux+Smack) but it would clear
the way for this case. And Yama could use a blob if it
wanted to.

-Kees