RHSA-2014:0439 - Security Advisory

Topic

Updated kernel-rt packages that fix multiple security issues, several bugs,
and add various enhancements are now available for Red Hat Enterprise MRG
2.5.

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.

Description

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

• A denial of service flaw was found in the way the Linux kernel's IPv6

implementation processed IPv6 router advertisement (RA) packets.
An attacker able to send a large number of RA packets to a target system
could potentially use this flaw to crash the target system. (CVE-2014-2309,
Important)

• A flaw was found in the way the Linux kernel's netfilter connection

tracking implementation for Datagram Congestion Control Protocol (DCCP)
packets used the skb_header_pointer() function. A remote attacker could use
this flaw to send a specially crafted DCCP packet to crash the system or,
potentially, escalate their privileges on the system. (CVE-2014-2523,
Important)

• A flaw was found in the way the Linux kernel's CIFS implementation

handled uncached write operations with specially crafted iovec structures.
An unprivileged local user with access to a CIFS share could use this flaw
to crash the system, leak kernel memory, or, potentially, escalate their
privileges on the system. (CVE-2014-0069, Moderate)

• A flaw was found in the way the Linux kernel handled pending Floating

Pointer Unit (FPU) exceptions during the switching of tasks. A local
attacker could use this flaw to terminate arbitrary processes on the
system, causing a denial of service, or, potentially, escalate their
privileges on the system. Note that this flaw only affected systems using
AMD CPUs on both 32-bit and 64-bit architectures. (CVE-2014-1438, Moderate)

• It was found that certain protocol handlers in the Linux kernel's

networking implementation could set the addr_len value without initializing
the associated data structure. A local, unprivileged user could use this
flaw to leak kernel stack memory to user space using the recvmsg, recvfrom,
and recvmmsg system calls. (CVE-2013-7263, CVE-2013-7265, Low)

• An information leak flaw was found in the Linux kernel's netfilter

connection tracking IRC NAT helper implementation that could allow a remote
attacker to disclose portions of kernel stack memory during IRC DCC (Direct
Client-to-Client) communication over NAT. (CVE-2014-1690, Low)

• A denial of service flaw was discovered in the way the Linux kernel's

SELinux implementation handled files with an empty SELinux security
context. A local user who has the CAP_MAC_ADMIN capability could use this
flaw to crash the system. (CVE-2014-1874, Low)

Red Hat would like to thank Al Viro for reporting CVE-2014-0069.
The CVE-2014-1690 issue was discovered by Daniel Borkmann of Red Hat.

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

Users are advised to upgrade to these updated packages, which upgrade the
kernel-rt kernel to version kernel-rt-3.10.33-rt32.33, correct these
issues, and fix the bugs and add the enhancements noted in the Red Hat
Enterprise MRG 2 Technical Notes. 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/site/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.

Affected Products

• MRG Realtime 2 x86_64

Fixes

• BZ - 1016735 - Apply IB performance patches to 3.10 realtime kernel
• BZ - 1032245 - RFE: rebase to a 3.10 kernel
• BZ - 1035875 - CVE-2013-7263 CVE-2013-7265 Kernel: net: leakage of uninitialized memory to user-space via recv syscalls
• BZ - 1052914 - CVE-2014-1438 kernel: x86: exceptions are not cleared in AMD FXSAVE workaround
• BZ - 1058748 - CVE-2014-1690 Kernel: netfilter: nf_nat: leakage of uninitialized buffer in IRC NAT helper
• BZ - 1058848 - Panic on unload of sit module unload and reading of /proc/<pid>/net/dev
• BZ - 1062356 - CVE-2014-1874 Kernel: SELinux: local denial-of-service
• BZ - 1064253 - CVE-2014-0069 kernel: cifs: incorrect handling of bogus user pointers during uncached writes
• BZ - 1067880 - hpsa driver version regression in MRG 2.5 kernel
• BZ - 1074471 - CVE-2014-2309 Kernel: net: IPv6: crash due to router advertisement flooding
• BZ - 1077343 - CVE-2014-2523 kernel: netfilter: nf_conntrack_dccp: incorrect skb_header_pointer API usages

CVEs

• CVE-2013-7265
• CVE-2013-7263
• CVE-2014-0069
• CVE-2014-2309
• CVE-2014-2523
• CVE-2014-1690
• CVE-2014-1874
• CVE-2014-1438

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_MRG/2/html/Technical_Notes/index.html