[tor-bugs] #3296 [Tor Client]: Exitnode that can't handle a predicted port -> endless circuit creation

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#3296: Exitnode that can't handle a predicted port -> endless circuit creation
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 Reporter:  arma        |          Owner:                    
     Type:  defect      |         Status:  needs_review      
 Priority:  major       |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Client  |        Version:                    
 Keywords:              |         Parent:                    
   Points:              |   Actualpoints:                    
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Changes (by nickm):

  * status:  new => needs_review


Comment:

 So afaict the issue is that we are checking whether all predicted ports
 are handled, when what we should be checking is whether all predicted
 ports are either handled or unhandleable.

 One possibility would be, if we ever reach the end of the "for (attempt =
 0; attempt < 2; attempt++)" loop in choose_good_exit_server_general, to
 tell rephist that the remaining predicted ports are unsupportable, and to
 remove them entirely.  Does that work here?

 If so, see branch "bug3296" in my public repository.

 (But consider that in the example you give, for us to get the "doomed exit
 at random" message, *every* exit  needs to have n_supported == -1, right?
 So if you're seeing that one, not only is it hopeless to build a circuit
 to cherrybomb for 5122; it is also hopeless to try to build a circuit at
 all, I think. Could that be another bug?)

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3296#comment:3>
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