Re: [BUG] [Babel] Quotes-in-strings not being escaped in python, breaking output

From: "Eric Schulte" <schulte.eric@gmail.com>
To: Christopher Allan Webber <cwebber@dustycloud.org>
Cc: emacs-orgmode@gnu.org
Subject: Re: [BUG] [Babel] Quotes-in-strings not being escaped in python, breaking output
Date: Mon, 22 Nov 2010 18:57:10 -0700	[thread overview]
Message-ID: <87d3pwpzt5.fsf@gmail.com> (raw)
In-Reply-To: <87aalijfdg.fsf@dustycloud.org> (Christopher Allan Webber's message of "Tue, 09 Nov 2010 16:34:19 -0600")

Hi,

Thanks for raising this issue up.  While I don't consider it a security
issue (code blocks are already executing arbitrary code on your system),
it is certainly a failure in the parsing of input from scripting
languages (actually any language which has single-quote delimited
strings).

I just pushed up a fix which should resolve these issues (and some
related issues) in ruby python and Haskell.

The following example now executes as expected for me.

Thanks for the report -- Eric

** reading from single-quote-delim languages
#+BEGIN_SRC python
return [['607', 'Show license short, name on the deed'],
        ['255', "'(message (concat 'hello ' 'world))"]]
#+END_SRC

#+results:
| 607 | Show license short, name on the deed |
| 255 | '(message (concat 'hello ' 'world))  |

#+begin_src ruby
  [['607', 'Show license, short name on the deed'],
   ['255', "))'(message (concat 'hello ' 'world"]]
#+end_src

#+results:
| 607 | Show license, short name on the deed |
| 255 | ))'(message (concat 'hello ' 'world  |

#+begin_src haskell
  [["'single quotes'", "b"], ["\"double quotes\"", "d"]]
#+end_src

#+results:
| 'single quotes' | b |
| "double quotes" | d |

Christopher Allan Webber <cwebber@dustycloud.org> writes:

> I worry about this a bit because of the possible security issue: the
> ability to execute arbitrary code, since the structure that gets
> constructed is eval'ed.
>
> eg:
>
> #+BEGIN_SRC python
> return [['607', 'Show license short name on the deed'],
>         ['255', "'))(message (concat 'hello ' 'world"]]
> #+END_SRC
>
> That constructs a set of listp objects which are evaluated and look
> like:
>
> '(("607" "Show license short name on the deed") ("255" ""))
> (message (concat "hello " "world"))
>
> It doesn't seem like the second one is being evaluated but it makes me
> nervous that it's being passed through eval like this at all.
>
> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>
>> It looks like \' and " are not being escaped in
>> org-babel-python-table-or-string, which is the problem.
>>
>> Christopher Allan Webber <cwebber@dustycloud.org> writes:
>>
>>> Strings with quotes in them aren't having the inner quotes escaped right
>>> while read by ob-python in python.  Example:
>>>
>>> #+BEGIN_SRC python
>>> return [['607', 'Show license short name on the deed'],
>>>         ['255', '"Smart" 404 pages']]
>>> #+END_SRC
>>>
>>> #+results:
>>> | 607 | Show license short name on the deed |       |           |
>>> | 255 |                                     | Smart | 404 pages |
>>>
>>>
>>>
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