Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263275AbTESXVH (ORCPT ); Mon, 19 May 2003 19:21:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263276AbTESXVH (ORCPT ); Mon, 19 May 2003 19:21:07 -0400 Received: from mail.jlokier.co.uk ([81.29.64.88]:45698 "EHLO mail.jlokier.co.uk") by vger.kernel.org with ESMTP id S263275AbTESXVF (ORCPT ); Mon, 19 May 2003 19:21:05 -0400 Date: Tue, 20 May 2003 00:33:53 +0100 From: Jamie Lokier To: Ingo Molnar Cc: Linus Torvalds , Christoph Hellwig , linux-kernel@vger.kernel.org, Rusty Russell , Ulrich Drepper Subject: Re: [patch] futex API cleanups, futex-api-cleanup-2.5.69-A2 Message-ID: <20030519233353.GD13706@mail.jlokier.co.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 761 Lines: 18 Ingo Molnar wrote: > > > - start the phasing out of FUTEX_FD. This i believe is quite unclean and > > > unrobust, [...] > > FUTEX_FD is an instant DoS, it allows the pinning of one page per file > descriptor, per thread. With a default limit of 1024 open files per > thread, and 256 threads (on a sane/conservative setup), this means 1 GB of > RAM can be pinned down by a normal unprivileged user. The correct solution [;)] is EP_FUTEX - allow a futex to be specified as the source of an epoll event. -- Jamie - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/