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From: <tomas@tuxteam.de>
To: help-gnu-emacs@gnu.org
Subject: Re: eval and security
Date: Mon, 24 Oct 2016 14:31:52 +0200	[thread overview]
Message-ID: <20161024123151.GB10964@tuxteam.de> (raw)
In-Reply-To: <d55be2b3-e2e5-f3a2-f712-13b58fd30e49@easy-emacs.de>

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On Mon, Oct 24, 2016 at 02:20:44PM +0200, Andreas Röhler wrote:
> Hi,
> 
> remember a saying like "avoid calls like (eval 'my-symbol) in
> lisp-code" as related to security issues.
> 
> Is there some reading to learn more? Maybe I'm mistaking something?

Perhaps because a randomly downloaded package can redefine 'my-symbol
to be something evil?

In any case, if you indirect your code through user-overridable
stuff (e.g. hooks), the least you can do is to use a defvar
marking the thing as "risky": then Emacs will do its best to
avoid changing it when the user doesn't expect it.

There's a chapter "Security Considerations" in the Emacs Lisp
manual[1].

regards

[1] https://www.gnu.org/software/emacs/manual/html_node/elisp/Security-Considerations.html
- -- t
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  reply	other threads:[~2016-10-24 12:31 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-24 12:20 eval and security Andreas Röhler
2016-10-24 12:31 ` tomas [this message]
2016-10-24 17:40   ` Andreas Röhler
2016-10-24 18:50   ` Philipp Stephani
2016-10-25  7:34     ` Andreas Röhler

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