[tor-bugs] #2954 [Tor Directory Authority]: Investigate weird dirauth warns/errors/oom/exploit attempts?

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#2954: Investigate weird dirauth warns/errors/oom/exploit attempts?
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 Reporter:  mikeperry                |          Owner:  mikeperry
     Type:  defect                   |         Status:  new      
 Priority:  critical                 |      Milestone:           
Component:  Tor Directory Authority  |        Version:           
 Keywords:                           |         Parent:           
   Points:                           |   Actualpoints:           
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 I spent some time trying to diagnose some very strange micro-descriptor
 behaviour that seemed to be causing my directory authority to oom. After
 some investigation involving truncated/embedded microdescriptors, it
 turned out to most likely be due to my box ooming and corrupting the
 microdescriptor cache which then triggered more ooms, and not the other
 way around.

 Removing the corrupted cache stopped the ooming and the warns about large
 keys and malloc failures. (Or, it could have just been that the exploit
 attempt stopped sometime during all the ooming, and then removing the
 cache ended the issue?).

 The microdesc code seems to be pretty sparse when it comes to logs,
 dumping weird microdescs, and other diagnostics. This took much longer
 than it should have to get to the bottom of it. But perhaps it was just
 due to byzantine failures and won't happen again.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2954>
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