[tor-bugs] #30921 [Core Tor/Tor]: hs-v3: Close intro circuits when cleaning up the client descriptor cache

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#30921: hs-v3: Close intro circuits when cleaning up the client descriptor cache
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 Reporter:  dgoulet             |          Owner:  dgoulet
     Type:  defect              |         Status:  needs_revision
 Priority:  Medium              |      Milestone:  Tor: 0.4.2.x-final
Component:  Core Tor/Tor        |        Version:
 Severity:  Normal              |     Resolution:
 Keywords:  tor-hs, tor-client  |  Actual Points:  0.1
Parent ID:  #28970              |         Points:  0.1
 Reviewer:  asn                 |        Sponsor:  Sponsor27-must
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Changes (by asn):

 * status:  needs_review => needs_revision


Comment:

 Hmm, some questions about this fix:

 - I'm not sure if the identified race condition is the cause of this
 assert. Looking at #28970, there are two asserts and the second one is on
 `hs_ident_intro_circ_is_valid()` which imples that the hs_ident exists but
 is zeroed out. IIUC, this seems to be the reason that we can't find a
 descriptor here, and not a race condition.

 - Just noting that `Regardless of the cause of the assert or not, we
 should always close pending intro circuits when cleaning up a descriptor`,
 seems like a step backwards from #22893. Am I right to say that we need to
 do this anyway so that we maintain our current suboptimal design, and
 there is no way around it as long as we don't do #22893?

 - I now see a bit of code dup between `cache_store_as_client()` and
 `cache_clean_v3_as_client()` perhaps we can tidy it up in one func.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/30921#comment:4>
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