[tor-bugs] #15901 [Tor]: apparent memory corruption -- very difficult to isolate

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#15901: apparent memory corruption -- very difficult to isolate
---------------------------+--------------------------------
     Reporter:  starlight  |      Owner:
         Type:  defect     |     Status:  new
     Priority:  critical   |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor        |    Version:  Tor: 0.2.5.12
   Resolution:             |   Keywords:
Actual Points:             |  Parent ID:
       Points:             |
---------------------------+--------------------------------

Comment (by starlight):

 Saw a new message with this one:

 {{{
 Unable to load microdesc consensus directory downloaded from server
 '154.35.175.225:80'. I'll try again soon.
 Error decoding microdescriptor digest
 "no3r7DN7eA+Thw8cstgD9CTAyrGV0CRhNjSqR050,Xs"
 }}}

 Detailed log attached to ticket.

 Once again, if anyone familiar with the code
 can suggest something to instrument, please
 let me know.  Is not too difficult to put in
 a hard-coded debug-register watchpoint if
 one can be identified.

 Have switched it to running ASAN+UBSAN in the
 hope something will shake out, but am not
 overly hopeful as it didn't work the last
 time.  Including UBSAN perhaps could make a
 difference.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/15901#comment:13>
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