delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2011/04/27/10:10:23

X-Recipient: archive-cygwin AT delorie DOT com
X-Spam-Check-By: sourceware.org
Date: Wed, 27 Apr 2011 16:08:51 +0200
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: False positive from access("/proc/registry/...", F_OK)
Message-ID: <20110427140851.GU3324@calimero.vinschen.de>
Reply-To: cygwin AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
References: <1QF1xL-1RJrwe0 AT fwd09 DOT aul DOT t-online DOT de>
MIME-Version: 1.0
In-Reply-To: <1QF1xL-1RJrwe0@fwd09.aul.t-online.de>
User-Agent: Mutt/1.5.21 (2010-09-15)
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Unsubscribe: <mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

On Apr 27 12:26, Christian Franke wrote:
> access("/proc/registry/...", F_OK) returns 0 for all (including
> nonexistent) entries below a registry key which cannot be opened:
> 
> Testcase (run with admin rights):
> 
> # cygcheck -f /bin/cygwin1.dll
> cygwin-1.7.9-1
> 
> # cd /proc/registry/HKEY_LOCAL_MACHINE
> 
> # ls SECURITY
> Cache  Policy  RXACT  SAM
> 
> # cygdrop -- ls SECURITY
> ls: reading directory SECURITY: Permission denied
> 
> # test -e SECURITY/NoSuchFile && echo yes
> 
> # cygdrop -- test -e SECURITY/NoSuchFile && echo yes
> yes
> 
> 
> Problem was likely introduced by fhandler_registry.cc change 1.52:
> 
>  fhandler_registry::exists ()
>  ...
>    if (!val_only)
>      hKey = open_key (path, KEY_READ, wow64, false);
>  - if (hKey != (HKEY) INVALID_HANDLE_VALUE)
>  + if (hKey != (HKEY) INVALID_HANDLE_VALUE || get_errno () == EACCES)
>      file_type = 1;
>    else
> 
> open_key() returns INVALID_HANDLE_VALUE and EACCESS also if an upper
> level key cannot be opened. The exists() function returns 1
> (virt_directory) then, it should return 0 (virt_none).

I don't remember anymore why I did that and naturally I also didn't
write a comment.

But what you say sounds right to me.  Please create a patch.


Thanks,
Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

--
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

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019