[tor-bugs] #23603 [Core Tor/Tor]: hs: Cleanup race between circuit close and free with the HS circuitmap

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#23603: hs: Cleanup race between circuit close and free with the HS circuitmap
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 Reporter:  dgoulet       |          Owner:  (none)
     Type:  defect        |         Status:  new
 Priority:  High          |      Milestone:  Tor: 0.3.2.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:  tor-hs        |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Comment (by nickm):

 So, here's a patch I came up with when I sorta believed the above theory:
 http://paste.debian.net/987018/

 But I found a problem with the theory above:  when we call
 `hs_circuitmap_remove_circuit()` in step 4, shouldn't we _either_ hit the
 "Could not find circuit" warning, or fail the "tmp == circ"  assertion?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23603#comment:2>
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