1.74.9. RHSA-2011:0163: Important kernel security and bug fix update

Updated kernel packages that fix one security issue and three bugs are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having important security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

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

This update fixes the following security issue:

* A flaw was found in the sctp_icmp_proto_unreachable() function in the Linux kernel's Stream Control Transmission Protocol (SCTP) implementation. A remote attacker could use this flaw to cause a denial of service. (CVE-2010-4526, Important)

This update also fixes the following bugs:

* Due to an off-by-one error, gfs2_grow failed to take the very last "rgrp" parameter into account when adding up the new free space. With this update, the GFS2 kernel properly counts all the new resource groups and fixes the "statfs" file correctly. (BZ#666792)

* Prior to this update, a multi-threaded application, which invoked popen(3) internally, could cause a thread stall by FILE lock corruption. The application program waited for a FILE lock in glibc, but the lock seemed to be corrupted, which was caused by a race condition in the COW (Copy On Write) logic. With this update, the race condition was corrected and FILE lock corruption no longer occurs. (BZ#667050)

* If an error occurred during I/O, the SCSI driver reset the "megaraid_sas" controller to restore it to normal state. However, on Red Hat Enterprise Linux 5, the waiting time to allow a full reset completion for the "megaraid_sas" controller was too short. The driver incorrectly recognized the controller as stalled, and, as a result, the system stalled as well. With this update, more time is given to the controller to properly restart, thus, the controller operates as expected after being reset. (BZ#667141)

Users should upgrade to these updated packages, which contain backported patches to correct these issues. The system must be rebooted for this update to take effect.