[tor-bugs] #7912 [Tor]: Cells that don't get inserted into cell queues can clog connection flushing

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#7912: Cells that don't get inserted into cell queues can clog connection flushing
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 Reporter:  asn                     |          Owner:                    
     Type:  defect                  |         Status:  needs_review      
 Priority:  major                   |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor                     |        Version:                    
 Keywords:  tor-relay 023-backport  |         Parent:                    
   Points:                          |   Actualpoints:                    
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Comment(by nickm):

 Replying to [comment:29 nickm]:
 > >you have circuit_set_p_circid_chan() clearing circ->p_delete_pending
 and marking the circuit ID unusable on the old channel, but
 circuit_set_n_circid_chan() *sets* circ->n_delete_pending in the analogous
 case (which is a no-op since the test for the if already implies that).
 That seems unlikely to be correct.
 >
 > Okay; will investigate and fix.

 Added a fixup commit; thanks!

 > >  we might want to consider more flexible policy than alternation.
 >
 > Agreed.

 (We should open a ticket for this; it feels like an 0.2.5 thing)

 > > How thoroughly has this been tested, given the number of different
 bits of code it touches?
 >
 > Hardly at all.  I *think* I ran it on a chutney network and it didn't
 explode, but that doesn't mean much.

 I can try it on another chutney network.  How else should we check?  I'd
 be especially worried about bugs that prevented deletes from getting sent
 entirely.  Any ideas about how can we audit for those?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7912#comment:30>
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