[tor-bugs] #16052 [Tor]: Hidden service socket exhaustion by opening many connections

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#16052: Hidden service socket exhaustion by opening many connections
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     Reporter:  asn     |      Owner:
         Type:  defect  |     Status:  new
     Priority:  normal  |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor     |    Version:
   Resolution:          |   Keywords:  tor-hs dos SponsorR SponsorU
Actual Points:          |  Parent ID:
       Points:          |
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Comment (by yawning):

 So where this stands now is:

  * ~~Refactor the code that touches origin_circuit_t.p_streams to use
 TOR_LIST_* so it's easier to audit the stream counter code that got added
 (per discussion with nickm).~~ (Moved to #16134)
  * ~~Test it.~~ (Behaves as expected per asn, though CPU consumption is
 still high, and exact behavior not finalized yet.)
  * Argue over what exactly should happen when the threshold is tripped
 (what I do now?  kill the circuit?  mess with circuit level flow control?
 Display MLP ascii art in the logs?).
  * Add a changes file.
  * Update the man page.

 When working on #16134, I found that I'm not doing book keeping in
 `circuit_mark_for_close()` but I view that as acceptable (no point in
 zeroing out the number of streams when the circuit is getting torn down
 anyway).

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/16052#comment:17>
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