From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:40878 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933738AbcHBQkH (ORCPT ); Tue, 2 Aug 2016 12:40:07 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u72F4IdT007127 for ; Tue, 2 Aug 2016 11:14:05 -0400 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0b-001b2d01.pphosted.com with ESMTP id 24jh2ypxay-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 02 Aug 2016 11:14:05 -0400 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 2 Aug 2016 11:14:04 -0400 Subject: Re: [fuse-devel] [RFC v3 0/2] Support for posix acls in fuse From: Michael Theall To: Seth Forshee , fuse-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, Miklos Szeredi , "Eric W. Biederman" , Michael j Theall , Jean-Pierre =?ISO-8859-1?Q?Andr=E9?= Date: Tue, 02 Aug 2016 10:13:58 -0500 In-Reply-To: <20160802033931.GA33767@ubuntu-hedt> References: <1470086846-19844-1-git-send-email-seth.forshee@canonical.com> <87d1lsjdlu.fsf@thinkpad.rath.org> <20160802033931.GA33767@ubuntu-hedt> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Message-Id: <1470150838.9444.7.camel@linux.vnet.ibm.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Mon, 2016-08-01 at 22:39 -0500, Seth Forshee wrote: > On Mon, Aug 01, 2016 at 04:03:57PM -0700, Nikolaus Rath wrote: > > > > On Aug 01 2016, Seth Forshee wrote: > > > > > > There's also a problem with default acls that I'm not sure > > > there's > > > currently a solution for. As far as I can tell FUSE_CREATE > > > doesn't give > > > back any indication of whether an existing file was opened or a > > > new file > > > was created. Without knowing that I cannot know whether or not > > > the inode > > > should inherit default acls from its parent. > > Would it be possible for the FUSE file system to implement this > > inheritance by a dumb-copy of the ACL-related xattrs of the parent? > > > > This would solve your problem. But in addition to that, it also > > seems to > > me that even if a file system uses default_permissions for ACL > > handling, > > it may want implement a different policy for permission > > inheritance... > In my opinion it's preferable for the kernel to handle all of this > and > for the filesystems to need only xattr support to get support for > acls. > > The inheritance behavior is standard for default acls. It shouldn't > be > left to individual filesystems to decide the inheritance policy. > > Thanks, > Seth In case this has any bearing, my filesystem would in fact interpret the ACLs from the xattrs in order to apply them to the backing filesystem (which supports ACLs but through a non-xattr interface). In my particular case, it would be okay for the kernel to assume the inherited ACLs since it should be the same as if the kernel requested the ACLs after creation. Regards, Michael Theall