Re: [patch] honour MNT_NOEXEC for access()

From: Horst H. von Brand
Date: Sun Oct 08 2006 - 23:33:43 EST


Stas Sergeev <stsp@xxxxxxxx> wrote:
> Arjan van de Ven wrote:
> >> but ld.so seems to be
> >> the special case - it is a kernel helper after all,
> > in what way is ld.so special in ANY way?

> It is a kernel helper.

Right. But what prevents anybody to have a hacked, non-testing, ld.so lying
around?

> Kernel does all the security
> checks before invoking it. However, when invoked
> directly, it have to do these checks itself. So it is
> special in a way that it have to do the security checks
> which otherwise only the kernel should do.

It just can't do them (reliably at least) in general. Call it a Unix/POSIX
design failure...
--
Dr. Horst H. von Brand User #22616 counter.li.org
Departamento de Informatica Fono: +56 32 2654431
Universidad Tecnica Federico Santa Maria +56 32 2654239
Casilla 110-V, Valparaiso, Chile Fax: +56 32 2797513

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