From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL autolearn=ham autolearn_force=no version=3.4.2 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by inbox.vuxu.org (OpenSMTPD) with SMTP id 64067c8c for ; Wed, 22 Jan 2020 20:56:24 +0000 (UTC) Received: (qmail 12165 invoked by uid 550); 22 Jan 2020 20:56:22 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 12147 invoked from network); 22 Jan 2020 20:56:21 -0000 Date: Wed, 22 Jan 2020 15:56:05 -0500 From: Rich Felker To: Florian Weimer Cc: 39236@debbugs.gnu.org, musl@lists.openwall.com Message-ID: <20200122205605.GF30412@brightrain.aerifal.cx> References: <20200122141557.GA8157@brightrain.aerifal.cx> <87ftg7k1at.fsf@oldenburg2.str.redhat.com> <20200122144243.GZ30412@brightrain.aerifal.cx> <87a76fjzpx.fsf@oldenburg2.str.redhat.com> <20200122151507.GB30412@brightrain.aerifal.cx> <87zhefik0y.fsf@oldenburg2.str.redhat.com> <20200122160743.GC30412@brightrain.aerifal.cx> <87v9p3ihvq.fsf@oldenburg2.str.redhat.com> <20200122171508.GD30412@brightrain.aerifal.cx> <87zheffca9.fsf@oldenburg2.str.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87zheffca9.fsf@oldenburg2.str.redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: Rich Felker Subject: Re: [musl] coreutils cp mishandles error return from lchmod On Wed, Jan 22, 2020 at 09:48:14PM +0100, Florian Weimer wrote: > * Rich Felker: > > >> Hmm. The way I read the musl code, the O_PATH descriptor already > >> exists. At this point, you can just chmod the O_PATH descriptor, and > >> have the kernel report EOPNOTSUPP if the file system does not support > >> that. > > > > Oh, you mean the second one after it's already open? Maybe that's ok. > > Yes, that's what I meant. > > > I was concerned it might follow the link and chmod the target at that > > point. > > In my tests, it works. I think it's also documented behavior for chown > on these pseudo-files. Do you know where we might find that documentation? > I also verified that closing an O_PATH descriptor does not release POSIX > advisory locks for the same file. But I'm wondering if there's still > something we are missing. Thanks, I hadn't thought to check that, but wouldn't have expected it to be a problem since O_PATH is not actually open to the file. Rich