On Fri, Apr 6, 2012 at 13:54, Andrew Lutomirski [off-list ref] wrote:

(FWIW, I think that CLONE_NEWPID interacts badly with unix socket
credentials and should be fixed as a prerequisite for making it easier
to access.)

sendmsg() is a big hair ball. And yes, I have all sorts of things on
my wish list that touch sendmsg(). I don't think, I'll get them
fullfilled anytime soon, though:

 - sendmsg() does lots of different things: sending on unconnected
sockets, sending file descriptors, sending unix decriptors, and
plain-old sending data. These operations have very different security
properties and implications. It would be awesome if BPF filters could
filter these different types of operations selectively.

 - ancillary data is a cool concept in general. We should use it more.
If I could send a memory mapping from one process to another, that
would solve so many problems. But I know, I am dreaming; I don't
expect to see this feature any time soon.


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