7.2 - RHSA-2013:0829

Problem Description:

Updated kernel-rt packages that fix several security issues and multiple bugs are now available for Red Hat Enterprise MRG 2.3.

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:

MRG Realtime for RHEL 6 Server v.2 - noarch, x86_64

3. Description:

Security fixes:

* It was found that the kernel-rt update RHBA-2012:0044 introduced an integer conversion issue in the Linux kernel's Performance Events implementation. This led to a user-supplied index into the perf_swevent_enabled array not being validated properly, resulting in out-of-bounds kernel memory access. A local, unprivileged user could use this flaw to escalate their privileges. (CVE-2013-2094, Important)

A public exploit for CVE-2013-2094 that affects Red Hat Enterprise MRG 2 is available. Refer to Red Hat Knowledge Solution 373743, linked to in the References, for further information and mitigation instructions for users who are unable to immediately apply this update.

* An integer overflow flaw, leading to a heap-based buffer overflow, was found in the way the Intel i915 driver in the Linux kernel handled the allocation of the buffer used for relocation copies. A local user with console access could use this flaw to cause a denial of service or escalate their privileges. (CVE-2013-0913, Important)

* It was found that the Linux kernel used effective user and group IDs instead of real ones when passing messages with SCM_CREDENTIALS ancillary data. A local, unprivileged user could leverage this flaw with a set user ID (setuid) application, allowing them to escalate their privileges. (CVE-2013-1979, Important)

* A race condition in install_user_keyrings(), leading to a NULL pointer dereference, was found in the key management facility. A local, unprivileged user could use this flaw to cause a denial of service. (CVE-2013-1792, Moderate)

* A NULL pointer dereference flaw was found in the Linux kernel's XFS file system implementation. A local user who is able to mount an XFS file system could use this flaw to cause a denial of service. (CVE-2013-1819, Moderate)

* An information leak was found in the Linux kernel's POSIX signals implementation. A local, unprivileged user could use this flaw to bypass the Address Space Layout Randomization (ASLR) security feature. (CVE-2013-0914, Low)

* A use-after-free flaw was found in the tmpfs implementation. A local user able to mount and unmount a tmpfs file system could use this flaw to cause a denial of service or, potentially, escalate their privileges. (CVE-2013-1767, Low)

* A NULL pointer dereference flaw was found in the Linux kernel's USB Inside Out Edgeport Serial Driver implementation. A local user with physical access to a system and with access to a USB device's tty file could use this flaw to cause a denial of service. (CVE-2013-1774, Low)

* A format string flaw was found in the ext3_msg() function in the Linux kernel's ext3 file system implementation. A local user who is able to mount an ext3 file system could use this flaw to cause a denial of service or, potentially, escalate their privileges. (CVE-2013-1848, Low)

* A heap-based buffer overflow flaw was found in the Linux kernel's cdc-wdm driver, used for USB CDC WCM device management. An attacker with physical access to a system could use this flaw to cause a denial of service or, potentially, escalate their privileges. (CVE-2013-1860, Low)

* A heap-based buffer overflow in the way the tg3 Ethernet driver parsed the vital product data (VPD) of devices could allow an attacker with physical access to a system to cause a denial of service or, potentially, escalate their privileges. (CVE-2013-1929, Low)

* Information leaks in the Linux kernel's cryptographic API could allow a local user who has the CAP_NET_ADMIN capability to leak kernel stack memory to user-space. (CVE-2013-2546, CVE-2013-2547, CVE-2013-2548, Low)

* Information leaks in the Linux kernel could allow a local, unprivileged user to leak kernel stack memory to user-space. (CVE-2013-2634, CVE-2013-2635, CVE-2013-3076, CVE-2013-3222, CVE-2013-3224, CVE-2013-3225, CVE-2013-3231, Low)

Red Hat would like to thank Andy Lutomirski for reporting CVE-2013-1979. CVE-2013-1792 was discovered by Mateusz Guzik of Red Hat EMEA GSS SEG Team.

4. Solution:

This update also fixes multiple bugs. Documentation for these changes will be available shortly from the Technical Notes document linked to in the References section.

Users should upgrade to these updated packages, which upgrade the kernel-rt kernel to version kernel-rt-3.6.11.2-rt33, correct these issues, and fix the bugs noted in the Red Hat Enterprise MRG 2 Technical Notes. The system must be rebooted for this update to take effect.

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/):

915592 - CVE-2013-1767 Kernel: tmpfs: fix use-after-free of mempolicy object 916191 - CVE-2013-1774 Kernel: USB io_ti driver NULL pointer dereference in routine chase_port 916646 - CVE-2013-1792 Kernel: keys: race condition in install_user_keyrings() 918009 - CVE-2013-1819 kernel: xfs: _xfs_buf_find oops on blocks beyond the filesystem end 918098 - build id problem - needed for systemtap and perf annotations 918512 - kernel: crypto: info leaks in report API 920471 - CVE-2013-0913 Kernel: drm/i915: heap writing overflow 920499 - CVE-2013-0914 Kernel: sa_restorer information leak 920783 - CVE-2013-1848 kernel: ext3: format string issues 921970 - CVE-2013-1860 kernel: usb: cdc-wdm buffer overflow triggered by device 924689 - CVE-2013-2634 kernel: Information leak in the Data Center Bridging (DCB) component 924690 - CVE-2013-2635 kernel: Information leak in the RTNETLINK component 927026 - disable NO_HZ by default missing from v3.6-rt 949932 - CVE-2013-1929 Kernel: tg3: buffer overflow in VPD firmware parsing 955216 - CVE-2013-3222 Kernel: atm: update msg_namelen in vcc_recvmsg() 955599 - CVE-2013-3224 Kernel: Bluetooth: possible info leak in bt_sock_recvmsg() 955629 - CVE-2013-1979 kernel: net: incorrect SCM_CREDENTIALS passing 955649 - CVE-2013-3225 Kernel: Bluetooth: RFCOMM - missing msg_namelen update in rfcomm_sock_recvmsg 956094 - CVE-2013-3231 Kernel: llc: Fix missing msg_namelen update in llc_ui_recvmsg 956162 - CVE-2013-3076 Kernel: crypto: algif - suppress sending source address information in recvmsg 962792 - CVE-2013-2094 kernel: perf_swevent_enabled array out-of-bound access