[tor-bugs] #8864 [Tor]: Hidden service: Suddenly the service does not respond to new connections (INTRODUCE2 cell on intro circ with no corresponding rend_intro_point_t)

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#8864: Hidden service: Suddenly the service does not respond to new connections
(INTRODUCE2 cell on intro circ with no corresponding rend_intro_point_t)
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     Reporter:  reiam    |      Owner:
         Type:  defect   |     Status:  needs_review
     Priority:  normal   |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor      |    Version:  Tor: 0.2.3.25
   Resolution:           |   Keywords:  tor-hs, 023-backport, 025-triaged,
Actual Points:           |  SponsorR, 027-triaged-1-in
       Points:           |  Parent ID:
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Comment (by asn):

 Hello,

 please see branch `bug8864` in my repo for a fix to this issue according
 to comment:7 and subsequent discussion. I decided to go with the shortest
 fix possible, because that function is quite hairy and improving the code
 quality would not be easy. We should open a ticket for this. Instead, I
 decided to write some more docs for that part of the function, to make its
 behavior more clear.

 It's also worth noting that this patch abides by two design decisions that
 are not clear in the spec. Namely:
 a) If a relay is not in the consensus anymore, we close any intro circs to
 it.
 b) If an intro circuit disappears, we free that intro point (this will
 change in #8239).
 This might or might not be worth noting down in rend-spec.txt.

 Also, I decided to term this as a bugfix on `0.2.3.10-alpha` because
 that's when this log message was introduced.

 FWIW, my patch is very similar to David's in comment:21, but splits
 changes into multiple commits, adds a changes file, and fixes some
 weirdness.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/8864#comment:33>
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