[tor-bugs] #6853 [Tor Directory Authority]: Relay-flag voting code has undefined behaviour

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#6853: Relay-flag voting code has undefined behaviour
-------------------------------------+--------------------------------------
 Reporter:  rransom                  |          Owner:  rransom           
     Type:  defect                   |         Status:  needs_review      
 Priority:  normal                   |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor Directory Authority  |        Version:                    
 Keywords:                           |         Parent:                    
   Points:                           |   Actualpoints:                    
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Changes (by nickm):

  * status:  new => needs_review


Comment:

 I did 1' : renamed flags to find every reference, then audited the code at
 all those points, then changed the name of flags back.  There were only a
 small number of references in 3 files (one of which was test_dir.c), so it
 was pretty easy.

 It turns out the case above is the only problem I could find in the code
 near these sites.

 We should eventually do (2) or something like it.

 I don't see any literal cases of (1<<31), though if somebody knows one,
 I'd like to fix it.  (I did a grep for "<<", then grepped all those for
 "31".)

 Please review branch "bug6853".

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/6853#comment:4>
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