[tor-bugs] #16480 [Tor]: connection_write_to_buf: indirect recursion for CONN_TYPE_CONTROL

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#16480: connection_write_to_buf: indirect recursion for CONN_TYPE_CONTROL
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     Reporter:  cypherpunks  |      Owner:
         Type:  defect       |     Status:  new
     Priority:  normal       |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor          |    Version:
   Resolution:               |   Keywords:
Actual Points:               |  Parent ID:
       Points:               |
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Comment (by cypherpunks):

 > Oh, oh, I know this one.
 >
 > Back in the day, Vidalia would ask a control port question with a really
 big answer (like "give me all the microdescs"), and Tor would put the
 answer on its control port, but then the outbuf would get too big, and the
 "is there too much on the outbuf" check would trigger, killing the
 connection.
 >
 > Maybe enough of the rest of the code has changed that this bad behavior
 wouldn't happen anymore? Or maybe it is just like it was?

 Structure for outbuf was changes since then, there are no need for
 connection's buf size limits anymore and code do not closes connection for
 such reason anymore.

 But comment for ab838bddb89fa3f37eeada29e8c10d16873b5e86 says:
 > Flush local controller connection buffers periodically as we're writing
 to them, so we avoid queueing 4+ megabytes of data before trying to flush.

 Is it still possible to queue so many bytes for control connection, why?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/16480#comment:5>
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