linux-kernel - Re: [PATCH -mm] Revoke core code: fix nommu arch compiling error bug

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <6791.1174909459@redhat.com>
Date:	Mon, 26 Mar 2007 12:44:19 +0100
From:	David Howells <dhowells@...hat.com>
To:	Pekka J Enberg <penberg@...helsinki.fi>
Cc:	Andrew Morton <akpm@...ux-foundation.org>, bryan.wu@...log.com,
	linux-kernel@...r.kernel.org, Hugh Dickins <hugh@...itas.com>,
	dhowells@...hat.com
Subject: Re: [PATCH -mm] Revoke core code: fix nommu arch compiling error bug 

Pekka J Enberg <penberg@...helsinki.fi> wrote:

> But what's more important is, can we do revoke_mapping() for NOMMU? AFAICT 
> we can, we just need to scan all the global vmas, right?

I don't know, what does it do?  Remember, once a NOMMU process thinks it has
the right to access a mapping, there's no way of stopping it doing so short of
killing the process.

With NOMMU as it stands, private mappings are private copies of the data, and
have no impact on the page cache and get no updates from it.  It's as if you
took a private writable mapping, touched every page and then mprotect()'d it.
This isn't necessarily ideal, but we're limited by the lack on an MMU.

David
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/