[tor-bugs] #14129 [Tor]: UDP DoS attack results in tor crash

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#14129: UDP DoS attack results in tor crash
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     Reporter:  jowr    |      Owner:
         Type:  defect  |     Status:  new
     Priority:  major   |  Milestone:  Tor: 0.2.6.x-final
    Component:  Tor     |    Version:  Tor: 0.2.6.1-alpha
   Resolution:          |   Keywords:  crash dos tor-relay 025-backport
Actual Points:          |  Parent ID:
       Points:          |
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Comment (by nickm):

 The failure is the assertion failure in dns.c.  It looks like
 connection_dns_remove was called on an edge connection that wasn't
 actually pending according to the DNS code.

 I don't see any harm in turning this from an "assert(0)" into a warning
 message.

 I don't see any easy way for a UDP flood to have triggered this assertion,
 though.  Very interesting.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/14129#comment:2>
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