[tor-bugs] #11156 [Tor]: "can't find a pluggable transport proxy" errors when obfsproxy started up

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#11156: "can't find a pluggable transport proxy" errors when obfsproxy started up
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     Reporter:  asn      |      Owner:
         Type:  defect   |     Status:  needs_review
     Priority:  normal   |  Milestone:  Tor: 0.2.4.x-final
    Component:  Tor      |    Version:
   Resolution:           |   Keywords:  024-backport tor-pt tor-client,
Actual Points:           |  tbb-needs
       Points:           |  Parent ID:
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Comment (by asn):

 Long shory short, it seems that there might be another 60s bug here.

 I managed to reproduce this bug without OONI. You just need to perform a
 well-timed `RESETCONF` signal right after hitting 10% bootstrapping.

 I think what happens, is that Tor connects to the bridge over PT and gets
 the descriptor. But at the same time, `RESETCONF` is called and the PT
 proxies are marked for potential restart. From then on
 `should_delay_dir_fetches()` returns true because of the `RESETCONF` till
 `pt_configure_remaining_proxies()` gets called (which is at the end of the
 `run_scheduled_events()` loop). So all the dir fetches caused by the new
 bridge descriptor get cancelled.

 Finally, when Tor calls `update_consensus_networkstatus_downloads()` after
 60s, it proceeds bootstrapping normally.

 Will look more into this.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11156#comment:19>
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