[tor-bugs] #5402 [Tor Client]: #5090 allows post-auth heap overflow

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#5402: #5090 allows post-auth heap overflow
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 Reporter:  arma        |          Owner:                    
     Type:  defect      |         Status:  new               
 Priority:  major       |      Milestone:  Tor: 0.2.2.x-final
Component:  Tor Client  |        Version:                    
 Keywords:              |         Parent:                    
   Points:              |   Actualpoints:                    
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Comment(by rransom):

 Replying to [ticket:5402 arma]:

 > And Nick points out:
 {{{
 We ought to audit uses of get_escaped_string_length in control.c
 nevertheless.  It is a *PHENOMINALLY BAD IDEA* in C to have
 independent functions that count the length of something and that
 parse it.  We should look for other cases of that antipattern too.
 }}}

 `get_escaped_string_length` in control.c is harmless -- it is only called
 from the two functions which immediately follow it in the file
 (`extract_escaped_string`, which does not attempt to unescape the string,
 and `decode_escaped_string`, which unescapes the string using the same
 rules that `get_escaped_string_length` uses).

 `decode_escaped_string` is only called from `handle_control_authenticate`,
 which can obviously be called before authenticating to the control port.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/5402#comment:2>
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