[tor-bugs] #4650 [Tor Client]: DisableDebuggerAttachment pretends to be disabled if you change it and hup

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#4650: DisableDebuggerAttachment pretends to be disabled if you change it and hup
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 Reporter:  arma        |          Owner:                    
     Type:  defect      |         Status:  new               
 Priority:  major       |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Client  |        Version:                    
 Keywords:              |         Parent:                    
   Points:              |   Actualpoints:                    
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 The feature from #3313 does a prctl or ptrace call if it's on during
 options_act(), and does a log_notice if it's off during options_act.

 So I can change it to off, hup, and get the log_notice saying attaching
 should work. But it doesn't actually do anything to make it work again.

 rransom points out quite rightly that our process isn't *supposed* to be
 able to do anything to make it work again. So the correct fix is to stop
 deceiving the user. Perhaps we should make it an invalid transition in
 options_transition_allowed()?

 Also, should we really be calling tor_disable_debugger_attach() on every
 hup? Seems like the sort of thing that we should have a static variable to
 remember.

 And finally (and related), if the option is off, you get your log_notice
 on every hup whether anything changed or no.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4650>
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