[tor-bugs] #8093 [Tor]: Jan 29 23:32:20.066 [Warning] Bug/attack: unexpected sendme cell from client. Closing circ.

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#8093: Jan 29 23:32:20.066 [Warning] Bug/attack: unexpected sendme cell from
client. Closing circ.
------------------------+---------------------------------------------------
 Reporter:  Gravitas    |          Owner:                    
     Type:  defect      |         Status:  new               
 Priority:  normal      |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor         |        Version:  Tor: 0.2.4.9-alpha
 Keywords:  tor-client  |         Parent:                    
   Points:              |   Actualpoints:                    
------------------------+---------------------------------------------------

Comment(by nickm):

 {{{
 20:23 < nickm> I think saying "bug/attack" here is misleading.  It could
 be
                somebody else's bug. It could be our own bug.  It could be
 an
                attack... probably not, though, since anybody doing this
 attack
                would be dumb to target servers that detect it, warn about
 it,
                and don't let it procede
 20:23 < nickm> The fact that the mode is 901 suggests that "somebody's got
 a
                bug" is the likeliest explanation
 20:26 < nickm> Maybe downgrade the warning to PROTOCOL_WARN in 0.2.4,
 leave it
                at warn but rewrite it in 0.2.5, and add some feature to
 count
                cells somewhere independently of the current count to see
 if
                there's any relay-side miscount?
 20:27 < nickm> The fact that this has only been reported relay-side
 suggests
                even stronger to me that it could be broken clients
 20:30 < nickm> does that seem plausible?
 20:31 < athena> yeah, agree make it PROTOCOL_WARN since we don't know the
                 cause, just that we saw something weird
 20:31 < athena> and add instrumentation
 }}}

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/8093#comment:19>
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