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4.70. gdm

Updated gdm packages that fix a bug are now available for Red Hat Enterprise Linux 6 Extended Update Support.
The GNOME Display Manager (GDM) is a highly configurable reimplementation of XDM, the X Display Manager. GDM allows you to log into your system with the X Window System running and supports running several different X sessions on your local machine at the same time.

Bug Fix

BZ#860645
When gdm was used to connect to a server via XDMCP (X Display Manager Control Protocol), another connection to a remote system using the "ssh -X" command resulted in wrong authorization with the X server. Consequently, applications such as xterm could not be displayed on the remote system. This update provides a compatible MIT-MAGIC-COOKIE-1 key in the described scenario, thus fixing this bug.
All users of gdm are advised to upgrade to these updated packages, which fix this bug.
Updated gdm packages that fix multiple bugs are now available for Red Hat Enterprise Linux 6.
The GNOME Display Manager (GDM) provides the graphical login screen, shown shortly after boot up, log out, and when user-switching.

Bug Fixes

BZ#661618
GDM did not properly queue up multiple authentication messages so that messages could quickly be overwritten by newer messages. The queueing mechanism has been modified, and this problem no longer occurs.
BZ#628462
If a Russian keyboard layout was chosen during system installation, the login screen was configured to use Russian input for user names and passwords by default. However, GDM did not provide any visible way to switch between keyboard layouts, and pressing Left Shift and Right Shift keys did not cause the input to change to ASCII mode in GDM. Consequently, users were not able to log in to the system. With this update, GDM allows users to switch keyboard layout properly using the keyboard layout indicator, and users can now log in as expected.
BZ#723515
GDM did not properly release file descriptors used with XDMCP indirect queries. As a consequence, the number of file descriptors used by GDM increased with every XDMCP chooser restart, which, in some cases, led to memory exhaustion and a GDM crash. The underlying GDM code has been modified to manage file descriptors properly, and the problem no longer occurs in this scenario.
BZ#670619
In multi-monitor setups, GDM always displayed the login window on the screen that was determined as active by the mouse pointer position. This behavior caused unpredictable login window placement in dual screen setups when using the NVIDIA's TwinView Dual-Display Architecture because the mouse pointer initially appeared exactly between the monitors outside of the visible screen. GDM now uses new logic to ensure that the initial placement of the mouse pointer and the login window are consistently on one screen.
BZ#645453
The GDM simple greeter login window displayed "Suspend", "Restart" and "Shut Down" buttons even though the buttons were disabled in GDM configuration and the PolicyKit toolkit disallowed any stop, restart, suspend actions on the system. With this update, GDM logic responsible for setting up the greeter login window has been modified and these buttons are no longer displayed under these circumstances
BZ#622561
When authenticating to a system and the fingerprint authentication method was enabled, but no fingerprint reader was attached to the machine, GDM erroneously displayed authentication method buttons for a brief moment. With this update, GDM displays authentication method buttons only if the authentication method is enabled and a reading device is connected.
BZ#708430
GDM did not properly handle its message queue. Therefore, when resetting a password on user login, GDM displayed an error message from a previous unsuccessful attempt. The queueing mechanism has been modified, and this problem no longer occurs.
BZ#688158
When logging into a system using LDAP authentication, GDM did not properly handle LDAP usernames containing backslash characters. As a consequence, such usernames were not recognized and users were not able to log in even though they provided valid credentials. With this update, GDM now handles usernames with backslash characters correctly and users can log in as expected.
All users of gdm are advised to upgrade to these updated packages, which fix these bugs.
Updated gdm packages that add one enhancement are now available for Red Hat Enterprise Linux 6.
The GNOME Display Manager (GDM) provides the graphical login screen, shown shortly after boot up, logout, and when user-switching.

Enhancement

BZ#799940
Previously, X server audit messages were not included by default in the X server log. Now, those messages are unconditionally included in the log. Also, with this update, verbose messages are added to the X server log if debugging is enabled in the /etc/gdm/custom.conf file (by setting "Enable=true" in the [debug] section).
All users of gdm are advised to upgrade to these updated packages, which add this enhancement.