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From: Warren Young <wyml@etr-usa.com>
To: cygwin-apps@cygwin.com
Subject: Re: [RFC] /etc/shells management (fish, mksh, posh, tcsh, zsh)
Date: Thu, 12 May 2016 21:44:00 -0000	[thread overview]
Message-ID: <8D27AE89-1DF7-4570-B9AF-8A4610B52964@etr-usa.com> (raw)
In-Reply-To: <b6d3465f-6630-5e05-bd35-30fb7d005304@cygwin.com>

On May 12, 2016, at 3:36 PM, Yaakov Selkowitz <yselkowitz@cygwin.com> wrote:
> 
> What are the consequences of having shells listed in /etc/shells which aren't on the system?

That file is a security feature, but the typical way Cygwin works — i.e. that normal users are allowed to install software, modify /etc/*, and so forth — nullifies its value.

But, if you do somehow lock down /etc/shells so that normal users can’t write to it, you’re also presumably locking down /bin, so a malicious user couldn’t drop in a bogus /bin/fish file and convince other software to run it as a shell.

Too bad there is no /etc/shells.d.  Then non-Base shells could just add themselves there.

  reply	other threads:[~2016-05-12 21:44 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <pe94jbtrjf32qn2u0mbtrful36o1trjguj@4ax.com>
     [not found] ` <ngvnm4$tms$1@ger.gmane.org>
     [not found]   ` <lro6jbph7mumea7qcf0jbdnut23kujk3i4@4ax.com>
     [not found]     ` <cf899cc5-4267-3f59-478e-b7ba5361e2eb@cygwin.com>
2016-05-12 21:36       ` Yaakov Selkowitz
2016-05-12 21:44         ` Warren Young [this message]
2016-05-13 10:29         ` Andrew Schulman
2016-05-13 14:30           ` Chris Sutcliffe

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