RHSA-2015:1778 - Security Advisory

Topic

Updated kernel packages that fix multiple security issues and several bugs
are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security 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 packages contain the Linux kernel, the core of any Linux
operating system.

• A flaw was found in the kernel's implementation of the Berkeley Packet

Filter (BPF). A local attacker could craft BPF code to crash the system by
creating a situation in which the JIT compiler would fail to correctly
optimize the JIT image on the last pass. This would lead to the CPU
executing instructions that were not part of the JIT code. (CVE-2015-4700,
Important)

• Two flaws were found in the way the Linux kernel's networking

implementation handled UDP packets with incorrect checksum values. A remote
attacker could potentially use these flaws to trigger an infinite loop in
the kernel, resulting in a denial of service on the system, or cause a
denial of service in applications using the edge triggered epoll
functionality. (CVE-2015-5364, CVE-2015-5366, Important)

• A flaw was found in the way the Linux kernel's ext4 file system handled

the "page size > block size" condition when the fallocate zero range
functionality was used. A local attacker could use this flaw to crash the
system. (CVE-2015-0275, Moderate)

• It was found that the Linux kernel's keyring implementation would leak

memory when adding a key to a keyring via the add_key() function. A local
attacker could use this flaw to exhaust all available memory on the system.
(CVE-2015-1333, Moderate)

• A race condition flaw was found in the way the Linux kernel's SCTP

implementation handled Address Configuration lists when performing Address
Configuration Change (ASCONF). A local attacker could use this flaw to
crash the system via a race condition triggered by setting certain ASCONF
options on a socket. (CVE-2015-3212, Moderate)

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

Dynamic Shared Object (vDSO) implementation performed address
randomization. A local, unprivileged user could use this flaw to leak
kernel memory addresses to user-space. (CVE-2014-9585, Low)

Red Hat would like to thank Daniel Borkmann for reporting CVE-2015-4700,
and Canonical for reporting the CVE-2015-1333 issue. The CVE-2015-0275
issue was discovered by Xiong Zhou of Red Hat, and the CVE-2015-3212 issue
was discovered by Ji Jianwen of Red Hat Engineering.

This update also fixes several bugs. Refer to the following Knowledgebase
article for further information:

https://access.redhat.com/articles/1614563

All kernel users are advised to upgrade to these updated packages, which
contain backported patches to 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.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.3 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.2 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.1 x86_64
• Red Hat Enterprise Linux Server - AUS 7.7 x86_64
• Red Hat Enterprise Linux Server - AUS 7.6 x86_64
• Red Hat Enterprise Linux Server - AUS 7.4 x86_64
• Red Hat Enterprise Linux Server - AUS 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.4 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.3 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.2 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.1 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.5 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.4 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.3 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.2 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux Server from RHUI 7 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.5 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.4 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.3 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.2 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.1 ppc64le
• Red Hat Enterprise Linux Server - TUS 7.7 x86_64
• Red Hat Enterprise Linux Server - TUS 7.6 x86_64
• Red Hat Enterprise Linux Server - TUS 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
• Red Hat Enterprise Linux EUS Compute Node 7.7 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.5 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.4 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.3 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.2 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.1 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.7 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.6 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.4 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.3 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.3 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.2 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

• BZ - 1181054 - CVE-2014-9585 kernel: ASLR bruteforce possible for vdso library
• BZ - 1193907 - CVE-2015-0275 kernel: fs: ext4: fallocate zero range page size > block size BUG()
• BZ - 1226442 - CVE-2015-3212 kernel: SCTP race condition allows list corruption and panic from userlevel
• BZ - 1233615 - CVE-2015-4700 kernel: Crafted BPF filters may crash kernel during JIT optimisation
• BZ - 1239029 - CVE-2015-5366 CVE-2015-5364 kernel: net: incorrect processing of checksums in UDP implementation
• BZ - 1245658 - CVE-2015-1333 kernel: denial of service due to memory leak in add_key()

CVEs

• CVE-2014-9585
• CVE-2015-5364
• CVE-2015-5366
• CVE-2015-3212
• CVE-2015-1333
• CVE-2015-0275
• CVE-2015-4700

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/articles/1614563