From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Tso Subject: Re: FIBMAP/FIEMAP discrepancy for CAP_SYS_RAWIO Date: Mon, 7 Sep 2009 09:28:48 -0400 Message-ID: <20090907132848.GA22901@mit.edu> References: <87y6osry4k.fsf@mid.deneb.enyo.de> <20090907105014.GV4197@webber.adilger.int> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Florian Weimer , linux-fsdevel@vger.kernel.org To: Andreas Dilger Return-path: Received: from thunk.org ([69.25.196.29]:35566 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752608AbZIGN2w (ORCPT ); Mon, 7 Sep 2009 09:28:52 -0400 Content-Disposition: inline In-Reply-To: <20090907105014.GV4197@webber.adilger.int> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Mon, Sep 07, 2009 at 12:50:14PM +0200, Andreas Dilger wrote: > On Sep 06, 2009 13:39 +0000, Florian Weimer wrote: > > The FIBMAP ioctl requires CAP_SYS_RAWIO, but FIEMAP doesn't. Why's > > that? Is it that there is no backwards-compatible way to introduce > > locking on the bmap path? > > I'm not sure why there is a root-only requirement for FIBMAP Historical reasons, I suspect --- back then only LILO needed it, and whoever added it decided it was safer only to allow root to have access to it. I don't think there's any good justification for FIBMAP to require privileges. - Ted