[tor-bugs] #4251 [Tor Hidden Services]: memory leak for hidden service?

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#4251: memory leak for hidden service?
---------------------------------+------------------------------------------
 Reporter:  arma                 |          Owner:  rransom           
     Type:  defect               |         Status:  accepted          
 Priority:  normal               |      Milestone:  Tor: 0.2.2.x-final
Component:  Tor Hidden Services  |        Version:                    
 Keywords:                       |         Parent:                    
   Points:                       |   Actualpoints:                    
---------------------------------+------------------------------------------
Changes (by rransom):

  * milestone:  => Tor: 0.2.2.x-final


Comment:

 Replying to [ticket:4251 arma]:
 > I ran moria1 under valgrind and it identified the following leak:
 {{{
 ==29415==    by 0x42C579: rend_services_introduce (rendservice.c:1347)
 ==29415==    by 0x46CFB2: circuit_build_needed_circs (circuituse.c:708)
 }}}

 src/or/rendservice.c:1347 is in `rend_service_launch_establish_intro`:
 {{{
   launched->rend_data = tor_malloc_zero(sizeof(rend_data_t));
 }}}

 When a service-side intro circuit opens and we already have enough intro
 points for its HS, we set its purpose to `CIRCUIT_PURPOSE_C_GENERAL` (in
 `rend_service_intro_has_opened`), but do not free and clear its
 `rend_data` field.  Fortunately, your Tor instance cannibalized that
 circuit for use as a hidden-service-related circuit and allocated a new
 `rend_data` for it, thereby leaking the old `rend_data`'s memory, while it
 was running under valgrind.  Nice catch!

 Bugfix probably on 0.0.6, when hidden services were introduced, but I
 should check that before I put it in a changes/ file.  Setting milestone
 to 0.2.2.x.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4251#comment:3>
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