New skb extension for use by LSMs (skb "security blob")?

[David Miller]

From: Paul Moore <paul at paul-moore.com>
Date: Wed, 21 Aug 2019 18:00:09 -0400

> I was just made aware of the skb extension work, and it looks very
> appealing from a LSM perspective.  As some of you probably remember,
> we (the LSM folks) have wanted a proper security blob in the skb for
> quite some time, but netdev has been resistant to this idea thus far.
> 
> If I were to propose a patchset to add a SKB_EXT_SECURITY skb
> extension (a single extension ID to be shared among the different
> LSMs), would that be something that netdev would consider merging, or
> is there still a philosophical objection to things like this?

Unlike it's main intended user (MPTCP), it sounds like LSM's would use
this in a way such that it would be enabled on most systems all the
time.

That really defeats the whole purpose of making it dynamic. :-/