From d6acecdd0ebb42e28ff28e04e0207cb01fa20910 Mon Sep 17 00:00:00 2001 From: David Zeuthen Date: Wed, 19 Dec 2012 19:28:29 +0000 Subject: Set XAUTHORITY environment variable if is unset The way it works is that if XAUTHORITY is unset, then its default value is $HOME/.Xauthority. But since we're changing user identity this will not work since $HOME will now change. Therefore, if XAUTHORITY is unset, just set its default value before changing identity. This bug only affected login managers using X Window Authorization but not explicitly setting the XAUTHORITY variable. You can argue that XAUTHORITY is broken since it forces uid-changing apps like pkexec(1) to do more work - and get involved in intimate details of how X works and so on - but that doesn't change how things work. Based on a patch from Peter Wu . https://bugs.freedesktop.org/show_bug.cgi?id=51623 Signed-off-by: David Zeuthen --- diff --git a/src/programs/pkexec.c b/src/programs/pkexec.c index 840eb3c..da9784a 100644 --- a/src/programs/pkexec.c +++ b/src/programs/pkexec.c @@ -608,6 +608,28 @@ main (int argc, char *argv[]) g_ptr_array_add (saved_env, g_strdup (value)); } + /* $XAUTHORITY is "special" - if unset, we need to set it to ~/.Xauthority. Yes, + * this is broken but it's unfortunately how things work (see fdo #51623 for + * details) + */ + if (g_getenv ("XAUTHORITY") == NULL) + { + const gchar *home; + + /* pre-2.36 GLib does not examine $HOME (it always looks in /etc/passwd) and + * this is not what we want + */ + home = g_getenv ("HOME"); + if (home == NULL) + home = g_get_home_dir (); + + if (home != NULL) + { + g_ptr_array_add (saved_env, g_strdup ("XAUTHORITY")); + g_ptr_array_add (saved_env, g_build_filename (home, ".Xauthority", NULL)); + } + } + /* Nuke the environment to get a well-known and sanitized environment to avoid attacks * via e.g. the DBUS_SYSTEM_BUS_ADDRESS environment variable and similar. */ -- cgit v0.9.0.2-2-gbebe