Synopsis

Important: kernel-rt security update

Type/Severity

Security Advisory: Important

Topic

Updated kernel-rt packages that fix multiple security issues 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 flaw was found in the way the Linux kernel's futex subsystem handled

the requeuing of certain Priority Inheritance (PI) futexes. A local,
unprivileged user could use this flaw to escalate their privileges on the
system. (CVE-2014-3153, Important)

• It was found that the Linux kernel's ptrace subsystem allowed a traced

process' instruction pointer to be set to a non-canonical memory address
without forcing the non-sysret code path when returning to user space.
A local, unprivileged user could use this flaw to crash the system or,
potentially, escalate their privileges on the system. (CVE-2014-4699,
Important)

Note: The CVE-2014-4699 issue only affected systems using an Intel CPU.

• It was found that the permission checks performed by the Linux kernel

when a netlink message was received were not sufficient. A local,
unprivileged user could potentially bypass these restrictions by passing a
netlink socket as stdout or stderr to a more privileged process and
altering the output of this process. (CVE-2014-0181, Moderate)

• It was found that the aio_read_events_ring() function of the Linux

kernel's Asynchronous I/O (AIO) subsystem did not properly sanitize the AIO
ring head received from user space. A local, unprivileged user could use
this flaw to disclose random parts of the (physical) memory belonging to
the kernel and/or other processes. (CVE-2014-0206, Moderate)

• An out-of-bounds memory access flaw was found in the Netlink Attribute

extension of the Berkeley Packet Filter (BPF) interpreter functionality in
the Linux kernel's networking implementation. A local, unprivileged user
could use this flaw to crash the system or leak kernel memory to user space
via a specially crafted socket filter. (CVE-2014-3144, CVE-2014-3145,
Moderate)

• An out-of-bounds memory access flaw was found in the Linux kernel's

system call auditing implementation. On a system with existing audit rules
defined, a local, unprivileged user could use this flaw to leak kernel
memory to user space or, potentially, crash the system. (CVE-2014-3917,
Moderate)

• A flaw was found in the way Linux kernel's Transparent Huge Pages (THP)

implementation handled non-huge page migration. A local, unprivileged user
could use this flaw to crash the kernel by migrating transparent hugepages.
(CVE-2014-3940, Moderate)

• An integer underflow flaw was found in the way the Linux kernel's Stream

Control Transmission Protocol (SCTP) implementation processed certain
COOKIE_ECHO packets. By sending a specially crafted SCTP packet, a remote
attacker could use this flaw to prevent legitimate connections to a
particular SCTP server socket to be made. (CVE-2014-4667, Moderate)

• An information leak flaw was found in the RAM Disks Memory Copy (rd_mcp)

backend driver of the iSCSI Target subsystem of the Linux kernel.
A privileged user could use this flaw to leak the contents of kernel memory
to an iSCSI initiator remote client. (CVE-2014-4027, Low)

Red Hat would like to thank Kees Cook of Google for reporting
CVE-2014-3153, Andy Lutomirski for reporting CVE-2014-4699 and
CVE-2014-0181, and Gopal Reddy Kodudula of Nokia Siemens Networks for
reporting CVE-2014-4667. Google acknowledges Pinkie Pie as the original
reporter of CVE-2014-3153. The CVE-2014-0206 issue was discovered by
Mateusz Guzik of Red Hat.

Users are advised to upgrade to these updated packages, which upgrade the
kernel-rt kernel to version kernel-rt-3.10.33-rt32.43 and correct these
issues. 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 - 1094265 - CVE-2014-0181 kernel: net: insufficient permision checks of netlink messages
• BZ - 1094602 - CVE-2014-0206 kernel: aio: insufficient sanitization of head in aio_read_events_ring()
• BZ - 1096775 - CVE-2014-3144 CVE-2014-3145 Kernel: filter: prevent nla extensions to peek beyond the end of the message
• BZ - 1102571 - CVE-2014-3917 kernel: DoS with syscall auditing
• BZ - 1103626 - CVE-2014-3153 kernel: futex: pi futexes requeue issue
• BZ - 1104097 - CVE-2014-3940 Kernel: missing check during hugepage migration
• BZ - 1108744 - CVE-2014-4027 Kernel: target/rd: imformation leakage
• BZ - 1113967 - CVE-2014-4667 kernel: sctp: sk_ack_backlog wrap-around problem
• BZ - 1115927 - CVE-2014-4699 kernel: x86_64: ptrace: sysret to non-canonical address

CVEs

• CVE-2014-3153
• CVE-2014-3144
• CVE-2014-0206
• CVE-2014-3145
• CVE-2014-4699
• CVE-2014-3940
• CVE-2014-0181
• CVE-2014-4667
• CVE-2014-4027
• CVE-2014-3917

References