Re: link() security

xystrus
2002-04-13T17:02:37Z

On Sat, Apr 13, 2002 at 05:59:54PM +0100, Alan Cox wrote:
> > http://openwall.com. Work based on Solar Designer's Openwall patch has
> > been brought forward to more recent 2.4 and 2.5 kernels. Both the
> > following projects implement the Openwall secure link feature:
> >
> > http://grsecurity.net
> > http://lsm.immunix.org
> >
> > This can break some applications that make assumptions wrt. link(2)
> > (Courier MTA for example).
>
> How practical is it to make this a mount option and to do so cleanly ?

Perhaps two options: one to allow creation of the link only when the
UIDs match; and the other to allow the link when GIDs match, to keep
Courier happy?