From: Casey Schaufler Subject: Re: [RFC][PATCH 00/12] Enhanced file stat system call Date: Tue, 24 Nov 2015 06:43:38 -0800 Message-ID: <5654779A.9000702@schaufler-ca.com> References: <20151120145422.18930.72662.stgit@warthog.procyon.org.uk> <564F4F4E.8060603@schaufler-ca.com> <20151124081519.GA16147@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: David Howells , arnd@arndb.de, linux-afs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org To: Christoph Hellwig Return-path: In-Reply-To: <20151124081519.GA16147@infradead.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On 11/24/2015 12:15 AM, Christoph Hellwig wrote: > On Fri, Nov 20, 2015 at 08:50:22AM -0800, Casey Schaufler wrote: >> How about relevant xattrs? SELinux context, ACL, that sort of thing. >> The fact that these are optional should be taken care of by (4). > Those are not simple, fixed size stat data and would make the system > call a giant mess. > I didn't say it would be easy. I do think that adding a system call that only deals with simple, fixed size data is going to fall short of solving "the problem". Actually, a Smack label is fixed size (256 bytes). I suspect there is a maximum for SELinux contexts as well. ACLs I'll grant you are infinite.