[tor-bugs] #12468 [Tor bundles/installation]: TBB unconditionally logs all Firefox output to disk

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#12468: TBB unconditionally logs all Firefox output to disk
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     Reporter:  rransom                   |      Owner:  erinn
         Type:  defect                    |     Status:  new
     Priority:  blocker                   |  Milestone:
    Component:  Tor bundles/installation  |    Version:
   Resolution:                            |   Keywords:
Actual Points:                            |  Parent ID:
       Points:                            |
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Comment (by rransom):

 Replying to [comment:2 cypherpunks]:
 > Some platforms wrongly associates stdout and stderr with a terminal
 device. Tor Browser Bundle's startup script broken for them if no terminal
 present, stdout leaks out and depends system written to some logs. Like
 unity+nautilus.

 Which version of Ubuntu are you using?  (I can't easily test on Ubuntu
 now, but other people will want to know.)  Are you using the standard
 configuration/state (i.e. default configuration of Unity started from the
 default desktop manager, and without running Nautilus from a terminal)?

 Which file descriptors are incorrectly reported as terminals?

 Are messages that a program sends to stdout displayed to the user
 immediately?  Are messages that a program sends to stderr displayed to the
 user immediately?

 Are messages that a program sends to stdout logged to disk, and if so,
 where?  Are messages that a program sends to stderr logged to disk, and if
 so, where?

 > Attaching script that detects issue.

 {{{
 if [ "$ARE_WE_RUNNING_IN_A_TERMINAL" -ne 0 ] && [ '!' -t 0 ]; then
     complain "BUG: Wrongly reported as running in terminal"
 else
    echo "Correct. Running in terminal" >&1
 fi
 }}}

 In the real script, `ARE_WE_RUNNING_IN_A_TERMINAL` only controls whether
 `complain` will write its message to stderr or run an X program to display
 the message.  The security checks are (currently) on lines 139 through
 146, and close whichever of stdout or stderr is not a terminal.

 It's actually perfectly reasonable for `ARE_WE_RUNNING_IN_A_TERMINAL` to
 equal `1` when stdin is not a terminal: for example, if a user types
 `./start-tor-browser </dev/null` in a terminal.
 `ARE_WE_RUNNING_IN_A_TERMINAL` can also be `1` if e.g. stdout is
 redirected to a file, in which case `complain` will still write to stderr.
 (This is why the security checks had to be separate from that variable.)

 I've attached a script (`list-ttys.sh`) to diagnose the state of a
 script's standard FDs more precisely.

 It is bad to have `ARE_WE_RUNNING_IN_A_TERMINAL` set to `1` when the user
 won't see messages sent to stderr, but that's a user-interface problem,
 and not just with TBB.  It would be much worse to have stdout attached to
 a pty that gets logged to disk, and I can't imagine that anyone would do
 that.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/12468#comment:3>
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