From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id D88A86B004D for ; Wed, 11 Mar 2009 14:53:47 -0400 (EDT) Date: Wed, 11 Mar 2009 19:53:39 +0100 From: Andrea Arcangeli Subject: Re: [aarcange@redhat.com: [PATCH] fork vs gup(-fast) fix] Message-ID: <20090311185339.GL27823@random.random> References: <20090311170611.GA2079@elte.hu> <20090311174103.GA11979@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090311174103.GA11979@elte.hu> Sender: owner-linux-mm@kvack.org To: Ingo Molnar Cc: Linus Torvalds , Nick Piggin , Hugh Dickins , KOSAKI Motohiro , KAMEZAWA Hiroyuki , linux-mm@kvack.org List-ID: Hello, On Wed, Mar 11, 2009 at 06:41:03PM +0100, Ingo Molnar wrote: > Hm, is there any security impact? Andrea is talking about data > corruption. I'm wondering whether that's just corruption > relative to whatever twisted semantics O_DIRECT has in this case > [which would be harmless], or some true pagecache corruption I don't think it's exploitable and I don't see this much as a security issue. This can only corrupt user data inside anonymous pages (not filesystem metadata or kernel pagecache). Side effects will be the usual ones of random user memory corruption or as worse it can lead to I/O corruption on disk, but only in user data. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org