7.8 - RHSA-2012:1323

Problem Description:

Updated kernel packages that fix multiple security issues and several 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. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

2. Relevant releases/architectures:

Red Hat Enterprise Linux (v. 5 server) - i386, ia64, noarch, ppc, s390x, x86_64 Red Hat Enterprise Linux Desktop (v. 5 client) - i386, noarch, x86_64

3. Description:

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

This update fixes the following security issues:

* A flaw was found in the way socket buffers (skb) requiring TSO (TCP segment offloading) were handled by the sfc driver. If the skb did not fit within the minimum-size of the transmission queue, the network card could repeatedly reset itself. A remote attacker could use this flaw to cause a denial of service. (CVE-2012-3412, Important)

* A use-after-free flaw was found in the xacct_add_tsk() function in the Linux kernel's taskstats subsystem. A local, unprivileged user could use this flaw to cause an information leak or a denial of service. (CVE-2012-3510, Moderate)

* A buffer overflow flaw was found in the hfs_bnode_read() function in the HFS Plus (HFS+) file system implementation in the Linux kernel. A local user able to mount a specially-crafted HFS+ file system image could use this flaw to cause a denial of service or escalate their privileges. (CVE-2012-2319, Low)

* A flaw was found in the way the msg_namelen variable in the rds_recvmsg() function of the Linux kernel's Reliable Datagram Sockets (RDS) protocol implementation was initialized. A local, unprivileged user could use this flaw to leak kernel stack memory to user-space. (CVE-2012-3430, Low)

Red Hat would like to thank Ben Hutchings of Solarflare (tm) for reporting CVE-2012-3412, and Alexander Peslyak for reporting CVE-2012-3510. The CVE-2012-3430 issue was discovered by the Red Hat InfiniBand team.

This update also fixes the following bugs:

* The cpuid_whitelist() function, masking the Enhanced Intel SpeedStep (EST) flag from all guests, prevented the "cpuspeed" service from working in the privileged Xen domain (dom0). CPU scaling was therefore not possible. With this update, cpuid_whitelist() is aware whether the domain executing CPUID is privileged or not, and enables the EST flag for dom0. (BZ#846125)

* If a delayed-allocation write was performed before quota was enabled, the kernel displayed the following warning message:

WARNING: at fs/quota/dquot.c:988 dquot_claim_space+0x77/0x112()

This was because information about the delayed allocation was not recorded in the quota structure. With this update, writes prior to enabling quota are properly accounted for, and the message is not displayed. (BZ#847326)

* In Red Hat Enterprise Linux 5.9, the DSCP (Differentiated Services Code Point) netfilter module now supports mangling of the DSCP field. (BZ#847327)

* Some subsystems clear the TIF_SIGPENDING flag during error handling in fork() paths. Previously, if the flag was cleared, the ERESTARTNOINTR error code could be returned. The underlying source code has been modified so that the error code is no longer returned. (BZ#847359)

* An unnecessary check for the RXCW.CW bit could cause the Intel e1000e NIC (Network Interface Controller) to not work properly. The check has been removed so that the Intel e1000e NIC works as expected. (BZ#852448)

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.

4. 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

To install kernel packages manually, use "rpm -ivh [package]". Do not use "rpm -Uvh" as that will remove the running kernel binaries from your system. You may use "rpm -e" to remove old kernels after determining that the new kernel functions properly on your system.

5. Bugs fixed (http://bugzilla.redhat.com/):

819471 - CVE-2012-2319 kernel: Buffer overflow in the HFS plus filesystem (different issue than CVE-2009-4020) 820039 - CVE-2012-3430 kernel: recv{from,msg}() on an rds socket can leak kernel memory 844714 - CVE-2012-3412 kernel: sfc: potential remote denial of service through TCP MSS option 847326 - WARNING: at fs/dquot.c:814 dquot_claim_reserved_space() in dmesg [rhel-5.8.z] 849722 - CVE-2012-3510 kernel: taskstats: use-after-free in xacct_add_tsk()