X-Recipient: archive-cygwin AT delorie DOT com DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; q=dns; s=default; b=IG HJf/C+eZ+ZsskNx8BeEz0eXbnQeQSRRKjUUh/5cHGtFxtzw4waFkCLiiuFKhGYR1 VFHQVBZx2hwGFn1SNEzmPthGfKU785GZZkwKEUdkOc7rPmcmy49G0kP+u3BRO3Yy UBMf8XhlCrAsx5NTlQwBDsVqmB5fnp63TSexppJT4= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; s=default; bh=O87g0Y8P XZbRpSS0563o8kpKKcg=; b=YLmfpzcX9OWZFJgAre0dzwLs4/ueRvb16r/nCisH xZDXvbflCK380foaLvYntPqhmBXPetqpw7SzAE7HllwHdxCrHNLU5d5RRpTw1KVV H6Us5dUT2mDct9cyFMacv81sDWd+jt4jcPfwrSBZR9Y8w+6FdSvXQKcjTEFGd08J h1Q= Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=0.8 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,FREEMAIL_REPLY,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=no version=3.3.2 X-HELO: mail-oa0-f44.google.com MIME-Version: 1.0 X-Received: by 10.182.28.7 with SMTP id x7mr11065660obg.43.1394541634738; Tue, 11 Mar 2014 05:40:34 -0700 (PDT) In-Reply-To: <542902046.20140311163047@yandex.ru> References: <542902046 DOT 20140311163047 AT yandex DOT ru> Date: Tue, 11 Mar 2014 08:40:34 -0400 Message-ID: Subject: Re: File permissions when using ACLs From: Charles Plager To: cygwin AT cygwin DOT com Content-Type: text/plain; charset=ISO-8859-1 Hi Andrey, I understand that Cygwin is emulating POSIX permissions (and, yes, we already turn this off using the /etc/fstab). What I don't understand is why it uses "special" permissions and not the standard "read/write" options that are available. One possibility I just though of: Cygwin uses special permissions in the case where the file is not executable (but readable or readable/writable)? I guess I can see that. I'd still love to hear from anybody who's experienced the vanishing permissions... Thanks! Charles On Tue, Mar 11, 2014 at 8:30 AM, Andrey Repin wrote: > Greetings, Charles Plager! > >> Short version: When writing to network drives (and probably local >> ones) as Cygwin is setup by default, we see the permissions being set >> using the ACLs where "creator owner" is given "full control" and >> "creator" group are given "read/execute", but by setting "special >> permissions" instead of just having "full control" or "read/execute" >> set. > >> Why does it not just set "full control" or "read/execute"? > > Cygwin by default mimicking POSIX permission set. > If this behavior is undesirable, You can work around it by letting operating > system control the ACL. > Modify cygdrive entry in /etc/fstab to include noacl option. > Then any files accessed outside direct/implied mounts will have permissions > controlled by OS. > >> Long, slightly different version: When the above permissions get set, >> we sometimes see (sometimes = 1 file in a million or less) a file that >> ends up with no permissions. Owner loses permissions, admin loses >> permissions and so far, IT has only been able to make the file go away >> by reformatting the drive. > >> When we tell Cygwin not to use ACLs (adding the following in >> /etc/fstab), this does not seem to happen (in 100 million or so files >> created). > >> none /cygdrive/ cygdrive binary,posix=0,user,noacl 0 0 > > >> This only seems to happen for files created by Cygwin with the ACL >> permissions (although, to be fair, without Cygwin, I don't know that >> anybody is generating as many files). I'm assuming it isn't Cygwin, >> per say, but rather something that interacts with how Cygwin setup the >> permissions (and given the rarity of the problem it is difficult to >> diagnose more thoroughly. > >> So, to sum up: > >> * Why use special permissions and not default settings when using ACLs? > >> * Anybody else experience files that lose all permissions? Any >> suggestions on resetting the file (short of reformatting the drive)? > >> * Any other hints/insights that might be useful here? > >> Thanks, >> Charles > >> p.s. We see this behavior for Cygwin 1.7.9 and beyond. In 1.7.5, it >> doesn't appear as if the ACLs are used and it acts as if "noacl" is >> set. > > > -- > WBR, > Andrey Repin (anrdaemon AT yandex DOT ru) 11.03.2014, <16:08> > > Sorry for my terrible english... > -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple