From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933595AbXCFAMP (ORCPT ); Mon, 5 Mar 2007 19:12:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933605AbXCFAMP (ORCPT ); Mon, 5 Mar 2007 19:12:15 -0500 Received: from x35.xmailserver.org ([64.71.152.41]:37914 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933595AbXCFAMO (ORCPT ); Mon, 5 Mar 2007 19:12:14 -0500 X-AuthUser: davidel@xmailserver.org Date: Mon, 5 Mar 2007 16:12:12 -0800 (PST) From: Davide Libenzi X-X-Sender: davide@alien.or.mcafeemobile.com To: Linus Torvalds cc: Linux Kernel Mailing List , Andrew Morton , Eric Dumazet Subject: Re: [patch v2] epoll use a single inode ... In-Reply-To: Message-ID: References: X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 5 Mar 2007, Linus Torvalds wrote: > On Mon, 5 Mar 2007, Davide Libenzi wrote: > > @@ -763,15 +767,17 @@ > > * using the inode number. > > */ > > error = -ENOMEM; > > - sprintf(name, "[%lu]", inode->i_ino); > > this.name = name; > > - this.len = strlen(name); > > - this.hash = inode->i_ino; > > + this.len = sprintf(name, "[%p]", ep); > > + this.hash = 0; > > Please don't expose kernel pointers to user space. > > It's much better to do something like > > static unsigned int epoll_inode; > > this.len = sprintf(name, "[%u]", ++epoll_inode); > > if you just need some pseudo-unique name to distinguish two epoll things > from each other (vs from a dup'ed fd). Heh, this is what Al was saying ;) I'm fine with that, but how about counter cycles (going back to zero)? Should we care to handle them correctly? - Davide