Subject: Re: PROT_EXEC mappings of vnodes -> VTEXT
To: Ben Harris <email@example.com>
From: Jason R Thorpe <firstname.lastname@example.org>
Date: 10/30/2001 06:45:36
On Tue, Oct 30, 2001 at 11:04:34AM +0000, Ben Harris wrote:
> In article <20011029215305.A11913@spathi.chuq.com> you write:
> >but I really don't think we should allow unpriviledged users
> >to cause any file they can read to become read-only just by
> >mapping it with PROT_EXEC. the VTEXT flag was originally used
> >just for the read-only part, I was overloading it when I used it
> >for affecting paging behaviour.
> Hmm. What's the reasoning behind protecting executables against being
> overwritten, and why doesn't it apply to shared libraries as well?
Yah, I'm a little fuzzy on this, too. If the idea is that you don't
want the underlying file changing while you deamand-page from it, then
that applies to shared libraries, too.
-- Jason R. Thorpe <email@example.com>