Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751646Ab0HUJmk (ORCPT ); Sat, 21 Aug 2010 05:42:40 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:38336 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750902Ab0HUJmi (ORCPT ); Sat, 21 Aug 2010 05:42:38 -0400 From: "Aneesh Kumar K. V" To: Nick Piggin , Neil Brown Cc: Al Viro , Christoph Hellwig , adilger@sun.com, corbet@lwn.net, npiggin@kernel.dk, hooanon05@yahoo.co.jp, bfields@fieldses.org, miklos@szeredi.hu, linux-fsdevel@vger.kernel.org, sfrench@us.ibm.com, philippe.deniel@CEA.FR, linux-kernel@vger.kernel.org Subject: Re: [PATCH -V18 04/13] vfs: Allow handle based open on symlinks In-Reply-To: <20100821083024.GB3448@amd> References: <1282269097-26166-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1282269097-26166-5-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <20100820083057.GA10039@infradead.org> <20100820195303.20b17210@notabene> <20100820115135.GQ31363@ZenIV.linux.org.uk> <20100821100900.4b15fe08@notabene> <20100821083024.GB3448@amd> User-Agent: Notmuch/0.3.1-58-g6607fd6 (http://notmuchmail.org) Emacs/24.0.50.1 (i686-pc-linux-gnu) Date: Sat, 21 Aug 2010 15:12:15 +0530 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1215 Lines: 28 On Sat, 21 Aug 2010 18:30:24 +1000, Nick Piggin wrote: > Thanks, I had both of the same concerns as Christoph with API > change and exposing symlink fds last time I looked at the patces, > actually. > > But they can probably be worked around or avoided. I think the more > important thing is whether it is worth supporting. This is > all restricted to root (or CAP_DAC_READ_SEARCH) only, right, and > what exact semantics they want. I would like to see more discussion > of what this enables and some results. > > For the case of avoiding expensive network revalidations in path name > lookup, do we even need to open symlinks? Could the security issues be > avoided by always having handle attached to an open fd? > For implementing a userspace file server that use handle for representing files (like NFS) we would require to have the ability to do different file system operations that can operate on symlink to work on handle too. -aneesh -- 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/