From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id 837036001DA for ; Thu, 28 Jan 2010 18:10:15 -0500 (EST) Date: Thu, 28 Jan 2010 15:09:28 -0800 (PST) From: Linus Torvalds Subject: Re: [Security] DoS on x86_64 In-Reply-To: <4B62141E.4050107@zytor.com> Message-ID: References: <144AC102-422A-4AA3-864D-F90183837EA3@googlemail.com> <20100128001802.8491e8c1.akpm@linux-foundation.org> <4B61B00D.7070202@zytor.com> <4B62141E.4050107@zytor.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: "H. Peter Anvin" Cc: Andrew Morton , security@kernel.org, "Luck, Tony" , James Morris , Mike Waychison , Michael Davidson , linux-mm@kvack.org, Ingo Molnar , Thomas Gleixner , Mathias Krause , Roland McGrath List-ID: On Thu, 28 Jan 2010, H. Peter Anvin wrote: > > So this patch, *plus* removing any delayed side effects from > SET_PERSONALITY() [e.g. the TIF_ABI_PENDING stuff in x86-64 which is > intended to have a forward action from SET_PERSONALITY() to > flush_thread()] might just work. I will try it out. Yeah, if you do that, then my "split up" patch isn't necessary. And it would make the code a whole lot more straightforward, and remove that whole crazy TIF_ABI_PENDING thing. Getting rid of the whole TIF_ABI_PENDING crap would be wonderful. It would make SET_PERSONALITY() (and flush_thread()) way more obvious. So that would be much better than the untested "split up flush_old_exec" patch I just sent out. So forget that patch, and let's go with your further cleanup approach instead. Linus -- 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