Subject: Re: mmap(), security and /dev/zero
To: Curt Sampson <cjs@cynic.net>
From: Daniel Carosone <dan@geek.com.au>
List: tech-security
Date: 06/24/2004 10:57:36
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On Thu, Jun 24, 2004 at 09:51:46AM +0900, Curt Sampson wrote:
>=20
> Doesn't the noexec flag allow you to do this already?
>=20

No, it needs this change to work. Otherwise, potentially, a program
executed from a r/o filesystem might be somehow tricked into loading
shlibs from a writable path.

If the shlib needed x bits in order to be executed, and the filesystem
it was on was noexec, then the potential hole is closed.

Count me amongst the group that like this change, btw.

--
Dan.

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