Devuan bug report logs - #209
ASCII: Default config in ~/.bash_logout crashes X server

Package: bash; Reported by: Michael Siegel <msi@malbolge.net>; dated Sun, 13 May 2018 22:03:01 UTC; Maintainer for bash is (unknown).


Message received at 209@bugs.devuan.org:


Received: (at 209) by bugs.devuan.org; 14 May 2018 15:10:02 +0000
To: 209@bugs.devuan.org
From: Michael Siegel <msi@malbolge.net>
Subject: Debian changelog for Bash in Stretch
Date: Mon, 14 May 2018 17:03:21 +0200

The Debian changelog for the package of Bash in Stretch includes:

  bash (4.4-3) unstable; urgency=medium

    * Apply upstream patches 006 - 007.
    * clear_console: Securely erase the current console. Closes:
      #845177.
    * Mark locales and time build dependencies with <!nocheck>.
      Closes: #838201.
    * Don't configure with --with-curses. Closes: #794588.

   -- Matthias Klose <doko@debian.org>  Fri, 20 Jan 2017 11:52:59 +0100


msi


Acknowledgement sent to Michael Siegel <msi@malbolge.net>:
Extra info received and forwarded to list. Copy sent to owner@bugs.devuan.org. Full text available.


Information forwarded to devuan-bugs@lists.dyne.org, owner@bugs.devuan.org:
bug#209; Package bash. Full text available.


Message received at submit@bugs.devuan.org:


Received: (at submit) by bugs.devuan.org; 13 May 2018 21:50:06 +0000
To: submit@bugs.devuan.org
From: Michael Siegel <msi@malbolge.net>
Subject: ASCII: Default config in ~/.bash_logout crashes X server
Date: Sun, 13 May 2018 23:42:09 +0200

Package: bash
Version: 4.4-5

When running X on VT1 and another user session (CLI) on VT2, logging out
on VT2, will either

  * crash the X server running on VT1, leaving you with a functional CLI
or
  * leave you with a blank screen and an apparently frozen-up system
    once you switch back to VT1

Running X with setuid root does not make any difference here. But if the
user on VT2 is root, X on VT1 will not crash when logging out on VT2.

In a discussion on Debian's IRC channel, I've been informed that this
problem is caused by the default configuration in ~/.bash_logout, which
looks like this:

  # ~/.bash_logout: executed by bash(1) when login shell exits.

  # when leaving the console clear the screen to increase privacy

  if [ "$SHLVL" = 1 ]; then
      [ -x /usr/bin/clear_console ] && /usr/bin/clear_console -q
  fi

Commenting out the if statement (or just deleting the file) will cure
the problem.

The culprit here is clear_console. Running /usr/bin/clear_console from
VT2 in the scenario described above will result in the same problems you
get when logging out.

fsmithred has also found that this problem does not occur on D-Bus-free
installations (with the above config in place).


msi


Acknowledgement sent to Michael Siegel <msi@malbolge.net>:
New bug report received and forwarded. Copy sent to owner@bugs.devuan.org. Full text available.


Report forwarded to devuan-bugs@lists.dyne.org, owner@bugs.devuan.org:
bug#209; Package bash. Full text available.


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Last modified: Mon, 20 Aug 2018 02:39:01 UTC