[tor-bugs] #8387 [Tor]: Unbuilt one-hop circuits sometimes hang around forever

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#8387: Unbuilt one-hop circuits sometimes hang around forever
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 Reporter:  mikeperry   |          Owner:  mikeperry         
     Type:  defect      |         Status:  assigned          
 Priority:  normal      |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor         |        Version:                    
 Keywords:  tor-client  |         Parent:                    
   Points:              |   Actualpoints:                    
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Comment(by mikeperry):

 So the specific change from #3443 that I think is likely the culprit here
 is the check TO_ORIGIN_CIRCUIT(victim)->cpath->state == CPATH_STATE_CLOSED
 at the top of the circuit culling loop of circuit_expire_building(). I
 added that check to allow circuits to exist until we sent their create
 cell, with the expectation that the orconn pruning code would eventually
 clean them up.

 It looks like run_connection_housekeeping() is the function that should
 prune connections in this case... Unless these connections haven't set
 their type to CONN_TYPE_DIR, it looks very much like they should still be
 getting closed there... Hrmm..

 I like Nick's idea of adding a function to tell us if we have any stale
 circuits and/or connections in normal usage, but I am not sure I could
 craft such a check myself to both cover all the cases of 'stale' and not
 introduce a bunch of false positive warns.. Probably 0.2.5.x material for
 that reason, unless Nick is more confident about exactly what checks we
 should do in such a case.

 In fact, it looks like run_connection_housekeeping() has one instance of
 such a check for wedged orconns (but not dirconns.. it seems to just have
 code to close those), but I've never seen its warns emitted for this bug.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/8387#comment:6>
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