RHBA-2014:1476 - Bug Fix Advisory

Topic

Updated grub packages that fix several bugs are now available for Red Hat
Enterprise Linux 6.

Description

The grub packages provide GRUB (Grand Unified Boot Loader), a boot loader
capable of booting a wide variety of operating systems.

This update fixes the following bugs:

• On some systems that are not case sensitive, the "bootx64" command incorrectly

launched the GRUB shell instead of booting the GRUB installer. With this update,
"bootx64" also checks for the existence of the GRUB booting file (BOOTX64),
which allows for using "bootx64" to boot GRUB on systems which are not case
sensitive. (BZ#1002809)

• A regular expression in the grub-install program could not match multipath

devices when the "user_friendly_name" option was set to "no". As a consequence,
the user was not able to install the GRUB utility on a specified device. To fix
this bug, the regular expression has been updated to match the requested device
names. As a result, GRUB now installs successfully. (BZ#1121321)

• Prior to this update, exiting the GRUB shell menu and rebooting the ISO file

on an extensible firmware interface (EFI) system changed the boot device path,
which in turn caused an assert error. As a consequence, GRUB sometimes failed to
boot. This update prevents the boot device path from being changed, and as a
result, exiting the GRUB shell and rebooting the ISO file now proceeds as
expected. (BZ#1129466)

• Previously, the biodisk function incorrectly returned "0" instead of the

correct values of the read and write calls. Due to this bug, the kernel under
some circumstances detected disk errors when booting, which caused the boot to
fail. This update fixes the behavior of biodisk, and the boot failure no longer
occurs. (BZ#1130209)

• Previously, booting GRUB with trusted boot (tboot) enabled under some

circumstances caused the tboot screen to be blue, making the text output
impossible to read. This update adds a number of conditions for graphic
initialization to GRUB, which ensure that the tboot screen displays in normal
colors. (BZ#1128137)

• Previously, the graphics_cls() and graphics_init() calls did not correctly

co-operate with GRUB. As a consequence, booting an ISO file with disabled VGA
caused the system to encounter an exception and automatically reboot. With this
update, the behavior of the mentioned calls has been corrected and the system
now successfully boots with disabled VGA. (BZ#1131205)

• When the "splashimage" option parameter was commented out or a serial console

was enabled in the /boot/EFI/redhat/grub.cfg file, the kernel did not initialize
the efifb graphic back end when booting an EFI system. As a consequence, VGA
text consoles displayed a blank screen instead of the intended output. With this
update, booting an EFI system uses efifb regardless of whether GRUB splash image
or a serial console are used, and the content of VGA consoles now displays as
expected. (BZ#1094978, BZ#1074914, BZ#1048681)

• Prior to this update, if a splash image was not used when booting an EFI

system, the serial console displayed a redundant grub_read() failure message
during the boot process. With this update, the underlying code has been fixed
and booting an EFI system without the GRUB splash image no longer generates
redundant failure messages. (BZ#1129436)

Users of grub are advised to upgrade to these updated packages, which fix these
bugs.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386

Fixes

• BZ - 1048681 - VGA will show any information after comment splashimage in /boot/EFI/redhat/grub.cfg when using EFI
• BZ - 1128137 - Showing a blue screen after installation when tboot is enabled

CVEs

(none)

References

(none)