Issued:

2012-07-19

Updated:

2012-07-19

RHBA-2012:1104 - kernel bug fix update

Synopsis

kernel bug fix update

Type/Severity

Bug Fix Advisory

Topic

Updated kernel packages that fix four bugs are now available for Red Hat Enterprise Linux 6.

Description

The kernel packages contain the Linux kernel, the core of any Linux operating system.

This update fixes the following bugs:

• Previously, futex operations on read-only (RO) memory maps did not work correctly. This broke workloads that had one or more reader processes performing the FUTEX_WAIT operation on a futex within a read-only shared file mapping and a writer process that had a writable mapping performing the FUTEX_WAKE operation. With this update, the FUTEX_WAKE operation is performed with a RO MAP_PRIVATE mapping, and is successfully awaken if another process updates the region of the underlying mapped file. (BZ#836904)

• When removing a bonding module, the bonding driver uses code separate from the net device operations to clean up the VLAN code. Recent changes to the kernel introduced a bug which caused a kernel panic if the vlan module was removed after the bonding module had been removed. To fix this problem, the VLAN group removal operations found in the bonding kill_vid path are now duplicated in alternate paths which are used when removing a bonding module. (BZ#837218)

• The bonding method for adding VLAN Identifiers (VIDs) did not always add the VID to a slave VLAN group. When the NETIF_F_HW_VLAN_FILTER flag was not set on a slave, the bonding module could not add new VIDs to it. This could cause networking problems and the system to be unreachable even if NIC messages did not indicate any problems. This update changes the bond VID add path to always add a new VID to the slaves (if the VID does not exist). This ensures that networking problems no longer occur in this scenario. (BZ#837227)

• Previously, reference counting was imbalanced in the slave add and remove paths for bonding. If a network interface controller (NIC) did not support the NETIF_F_HW_VLAN_FILTER flag, the bond_add_vlans_on_slave() and bond_del_vlans_on_slave() functions did not work properly, which could lead to a kernel panic if the VLAN module was removed while running. The underlying source code for adding and removing a slave and a VLAN has been revised and now also contains a common path, so that kernel crashes no kernel no longer occur in the described scenario. (BZ#837843)

All users of kernel are advised to upgrade to these updated packages, which fix these bugs. The system must be rebooted for this update to take effect.

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/knowledge/articles/11258

Affected Products

Updated Packages

• kernel-debug-2.6.32-279.2.1.el6.s390x.rpm
• kernel-2.6.32-279.2.1.el6.src.rpm
• kernel-debug-2.6.32-279.2.1.el6.x86_64.rpm
• kernel-headers-2.6.32-279.2.1.el6.ppc64.rpm
• python-perf-debuginfo-2.6.32-279.2.1.el6.x86_64.rpm
• python-perf-debuginfo-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-debuginfo-common-ppc64-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-devel-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-debug-2.6.32-279.2.1.el6.i686.rpm
• kernel-bootwrapper-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-kdump-debuginfo-2.6.32-279.2.1.el6.s390x.rpm
• kernel-debug-devel-2.6.32-279.2.1.el6.s390x.rpm
• perf-debuginfo-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-kdump-devel-2.6.32-279.2.1.el6.s390x.rpm
• perf-debuginfo-2.6.32-279.2.1.el6.s390x.rpm
• kernel-debuginfo-common-i686-2.6.32-279.2.1.el6.i686.rpm
• kernel-debug-devel-2.6.32-279.2.1.el6.x86_64.rpm
• perf-2.6.32-279.2.1.el6.ppc64.rpm
• python-perf-2.6.32-279.2.1.el6.x86_64.rpm
• perf-debuginfo-2.6.32-279.2.1.el6.i686.rpm
• python-perf-debuginfo-2.6.32-279.2.1.el6.s390x.rpm
• perf-2.6.32-279.2.1.el6.i686.rpm
• kernel-debug-devel-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-devel-2.6.32-279.2.1.el6.x86_64.rpm
• kernel-debug-debuginfo-2.6.32-279.2.1.el6.x86_64.rpm
• python-perf-2.6.32-279.2.1.el6.s390x.rpm
• kernel-headers-2.6.32-279.2.1.el6.i686.rpm
• kernel-debuginfo-2.6.32-279.2.1.el6.i686.rpm
• kernel-debuginfo-common-x86_64-2.6.32-279.2.1.el6.x86_64.rpm
• kernel-debug-devel-2.6.32-279.2.1.el6.i686.rpm
• perf-2.6.32-279.2.1.el6.x86_64.rpm
• kernel-2.6.32-279.2.1.el6.i686.rpm
• kernel-2.6.32-279.2.1.el6.x86_64.rpm
• python-perf-debuginfo-2.6.32-279.2.1.el6.i686.rpm
• kernel-headers-2.6.32-279.2.1.el6.x86_64.rpm
• perf-debuginfo-2.6.32-279.2.1.el6.x86_64.rpm
• kernel-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-debug-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-debuginfo-common-s390x-2.6.32-279.2.1.el6.s390x.rpm
• kernel-devel-2.6.32-279.2.1.el6.s390x.rpm
• kernel-debuginfo-2.6.32-279.2.1.el6.x86_64.rpm
• kernel-debuginfo-2.6.32-279.2.1.el6.ppc64.rpm
• perf-2.6.32-279.2.1.el6.s390x.rpm
• kernel-2.6.32-279.2.1.el6.s390x.rpm
• kernel-devel-2.6.32-279.2.1.el6.i686.rpm
• kernel-firmware-2.6.32-279.2.1.el6.noarch.rpm
• python-perf-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-debug-debuginfo-2.6.32-279.2.1.el6.s390x.rpm
• kernel-debug-debuginfo-2.6.32-279.2.1.el6.i686.rpm
• kernel-headers-2.6.32-279.2.1.el6.s390x.rpm
• python-perf-2.6.32-279.2.1.el6.i686.rpm
• kernel-debug-debuginfo-2.6.32-279.2.1.el6.ppc64.rpm
• kernel-debuginfo-2.6.32-279.2.1.el6.s390x.rpm
• kernel-kdump-2.6.32-279.2.1.el6.s390x.rpm
• kernel-doc-2.6.32-279.2.1.el6.noarch.rpm

Fixes

• This content is not included.BZ - 837227

CVEs

(none)

References

(none)

Additional information

• The Red Hat security contact is This content is not included.secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.
• Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.