From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.bugs Subject: bug#12632: file permissions checking mishandled when setuid Date: Sun, 14 Oct 2012 13:40:52 -0700 Organization: UCLA Computer Science Department Message-ID: <507B2354.3030408@cs.ucla.edu> References: <5078CAB6.7020509@cs.ucla.edu> <83fw5i7s4p.fsf@gnu.org> <83a9vq7oqh.fsf@gnu.org> <507A58CC.10209@cs.ucla.edu> <83fw5h5yo6.fsf@gnu.org> <507B010F.20105@cs.ucla.edu> <831uh06gqd.fsf@gnu.org> <507B15B0.2040802@cs.ucla.edu> <83txtw4xmk.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1350247325 14165 80.91.229.3 (14 Oct 2012 20:42:05 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 14 Oct 2012 20:42:05 +0000 (UTC) Cc: 12632@debbugs.gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Oct 14 22:42:12 2012 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1TNV0l-0008Rs-OF for geb-bug-gnu-emacs@m.gmane.org; Sun, 14 Oct 2012 22:42:11 +0200 Original-Received: from localhost ([::1]:34035 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TNV0e-00030z-Nx for geb-bug-gnu-emacs@m.gmane.org; Sun, 14 Oct 2012 16:42:04 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:43824) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TNV0b-0002rc-2A for bug-gnu-emacs@gnu.org; Sun, 14 Oct 2012 16:42:01 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TNV0Z-0000hu-Sc for bug-gnu-emacs@gnu.org; Sun, 14 Oct 2012 16:42:00 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:33937) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TNV0Z-0000hn-P5 for bug-gnu-emacs@gnu.org; Sun, 14 Oct 2012 16:41:59 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.72) (envelope-from ) id 1TNV1a-0007LH-Gx for bug-gnu-emacs@gnu.org; Sun, 14 Oct 2012 16:43:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Paul Eggert Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 14 Oct 2012 20:43:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 12632 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: patch Original-Received: via spool by 12632-submit@debbugs.gnu.org id=B12632.135024732828161 (code B ref 12632); Sun, 14 Oct 2012 20:43:02 +0000 Original-Received: (at 12632) by debbugs.gnu.org; 14 Oct 2012 20:42:08 +0000 Original-Received: from localhost ([127.0.0.1]:44187 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TNV0g-0007K9-IK for submit@debbugs.gnu.org; Sun, 14 Oct 2012 16:42:07 -0400 Original-Received: from smtp.cs.ucla.edu ([131.179.128.62]:38562) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TNV0b-0007Jd-Mi for 12632@debbugs.gnu.org; Sun, 14 Oct 2012 16:42:03 -0400 Original-Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id E2EEDA60003; Sun, 14 Oct 2012 13:40:52 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Original-Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id PoDV5Aqr+qYa; Sun, 14 Oct 2012 13:40:52 -0700 (PDT) Original-Received: from [192.168.1.3] (pool-108-23-119-2.lsanca.fios.verizon.net [108.23.119.2]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id 8F75EA60002; Sun, 14 Oct 2012 13:40:52 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 In-Reply-To: <83txtw4xmk.fsf@gnu.org> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.13 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) X-Received-From: 140.186.70.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:65616 Archived-At: On 10/14/2012 01:17 PM, Eli Zaretskii wrote: > If euidaccess always agrees with stat, why does it make sense to > switch check_existing to using euidaccess euidaccess always agrees with 'stat' with respect to access checks, but there are other reasons that 'stat' could fail, e.g., on a file that is too large for 'stat' to represent the size. In cases such as these, we want euidaccess here, because euidaccess shouldn't fail for these other reasons. > You are talking about the directories leading to the file. I was > talking about the file itself. OK, but in this context it doesn't make sense to talk about just the file itself, since the file is being accessed via a name, and one needs proper permissions to use the name. For both access and euidaccess, the F_OK check means "I don't care about the permissions about the file itself; all I care about are the permissions on the file's name", as far as permissions are concerned.