RHSA-2015:0694 - 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.

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

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

replacing of remote attributes under certain conditions. A local user with
access to XFS file system mount could potentially use this flaw to escalate
their privileges on the system. (CVE-2015-0274, Important)

• A flaw was found in the way the Linux kernel's splice() system call

validated its parameters. On certain file systems, a local, unprivileged
user could use this flaw to write past the maximum file size, and thus
crash the system. (CVE-2014-7822, Moderate)

• A race condition flaw was found in the Linux kernel's ext4 file system

implementation that allowed a local, unprivileged user to crash the system
by simultaneously writing to a file and toggling the O_DIRECT flag using
fcntl(F_SETFL) on that file. (CVE-2014-8086, Moderate)

• It was found that due to excessive files_lock locking, a soft lockup

could be triggered in the Linux kernel when performing asynchronous I/O
operations. A local, unprivileged user could use this flaw to crash the
system. (CVE-2014-8172, Moderate)

• A NULL pointer dereference flaw was found in the way the Linux kernel's

madvise MADV_WILLNEED functionality handled page table locking. A local,
unprivileged user could use this flaw to crash the system. (CVE-2014-8173,
Moderate)

Red Hat would like to thank Eric Windisch of the Docker project for
reporting CVE-2015-0274, and Akira Fujita of NEC for reporting
CVE-2014-7822.

Bug fixes:

• A patch removing the xt_connlimit revision zero ABI was not reverted in

the kernel-rt package, which caused problems because the iptables package
requires this revision. A patch to remove the xt_connlimit revision 0 was
reverted from the kernel-rt sources to allow the iptables command to
execute correctly. (BZ#1169755)

• With an older Mellanox Connect-IB (mlx4) driver present in the MRG

Realtime kernel, a race condition could occur that would cause a loss of
connection. The mlx4 driver was updated, resolving the race condition and
allowing proper connectivity. (BZ#1182246)

• The MRG Realtime kernel did not contain the appropriate code to resume

after a device failed, causing the volume status after a repair to not be
properly updated. A "refresh needed" was still listed in the "lvs" output
after executing the "lvchange --refresh" command. A patch was added that
adds the ability to correctly restore a transiently failed device upon
resume. (BZ#1159803)

• The sosreport executable would hang when reading

/proc/net/rpc/use-gss-proxy because of faulty wait_queue logic in the proc
handler. This wait_queue logic was removed from the proc handler, allowing
the reads to correctly return the current state. (BZ#1169900)

Enhancements:

• The MRG Realtime kernel-rt sources have been modified to take advantage

of the updated 3.10 kernel sources that are available with the Red Hat
Enterprise Linux 7 releases. (BZ#1172844)

• The MRG Realtime version of the e1000e driver has been updated to provide

support for the Intel I218-LM network adapter. (BZ#1191767)

• The MRG Realtime kernel was updated to provide support for the

Mellanox Connect-IB (mlx5). (BZ#1171363)

• The rt-firmware package has been updated to provide additional firmware

files required by the new version of the Red Hat Enterprise MRG 2.5 kernel
(BZ#1184251)

All kernel-rt users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues and add these
enhancements. 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

• MRG Realtime 2 x86_64

Fixes

• BZ - 1151353 - CVE-2014-8086 Kernel: fs: ext4 race condition
• BZ - 1163792 - CVE-2014-7822 kernel: splice: lack of generic write checks
• BZ - 1169755 - iptables: Protocol wrong type for socket (regression, bisected)
• BZ - 1171363 - realtime kernel does not support Mellanox Connect-IB(mlx5)
• BZ - 1172844 - RFE: rebase the 3.10 kernel-rt
• BZ - 1195248 - CVE-2015-0274 kernel: xfs: replacing remote attributes memory corruption
• BZ - 1198457 - CVE-2014-8173 kernel: NULL pointer dereference in madvise(MADV_WILLNEED) support
• BZ - 1198503 - CVE-2014-8172 kernel: soft lockup on aio

CVEs

• CVE-2014-7822
• CVE-2014-8086
• CVE-2014-8172
• CVE-2015-0274
• CVE-2014-8173

References

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