Re: [PATCH 0/3] New system call, unshare

[serue@us.ibm.com]

Quoting Florian Weimer (fw@deneb.enyo.de):
> * Janak Desai:
> 
> > With unshare, namespace setup can be done using PAM session
> > management functions without patching individual commands.
> 
> I don't think it's a good idea to use security-critical code well

Note that this patch is not removing the CAP_SYS_ADMIN requirement,
just allowing the operation to happen outside of clone().  Unlike
domain transitions in selinux, which should be tied to exec() so
as to tie them to known code, I don't see what clone() would provide
in terms of safety which we are losing.

> without its original specification.  Clearly the current situation
> sucks, but this is mainly a lack of PAM functionality, IMHO.

I'm not sure this is to do with PAM functionality, rather than
just its design.  Is there a way of "fixing" pam so that we don't
need unshare()?

thanks,
-serge