Synopsis: Important: kernel security, bug fix, and enhancement update
Advisory ID: SLSA-2014:0786-1
Issue Date: 2014-06-24
CVE Numbers: CVE-2014-2851
CVE-2014-1737
CVE-2014-1738
CVE-2014-3153
CVE-2014-2568
CVE-2014-0206
CVE-2014-3144
CVE-2014-3145
—
* 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)
* A use-after-free flaw was found in the way the ping_init_sock() function
of the Linux kernel handled the group_info reference counter. A local,
unprivileged user could use this flaw to crash the system or, potentially,
escalate their privileges on the system. (CVE-2014-2851, Important)
* Use-after-free and information leak flaws were found in the way the
Linux kernel’s floppy driver processed the FDRAWCMD IOCTL command. A local
user with write access to /dev/fdX could use these flaws to escalate their
privileges on the system. (CVE-2014-1737, CVE-2014-1738, Important)
* 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 information leak flaw was found in the way the skb_zerocopy()
function copied socket buffers (skb) that are backed by user-space buffers
(for example vhost-net and Xen netback), potentially allowing an attacker
to read data from those buffers. (CVE-2014-2568, Low)
This update also fixes the following bugs:
* Due to incorrect calculation of Tx statistics in the qlcninc driver,
running the “ethtool -S ethX” command could trigger memory corruption. As
a consequence, running the sosreport tool, that uses this command,
resulted in a kernel panic. The problem has been fixed by correcting the
said statistics calculation.
* When an attempt to create a file on the GFS2 file system failed due to a
file system quota violation, the relevant VFS inode was not completely
uninitialized. This could result in a list corruption error. This update
resolves this problem by correctly uninitializing the VFS inode in this
situation.
* Due to a race condition in the kernel, the getcwd() system call could
return “/” instead of the correct full path name when querying a path name
of a file or directory. Paths returned in the “/proc” file system could
also be incorrect. This problem was causing instability of various
applications. The aforementioned race condition has been fixed and
getcwd() now always returns the correct paths.
In addition, this update adds the following enhancements:
* The kernel mutex code has been improved. The changes include improved
queuing of the MCS spin locks, the MCS code optimization, introduction of
the cancellable MCS spin locks, and improved handling of mutexes without
wait locks.
* The handling of the Virtual Memory Area (VMA) cache and huge page faults
has been improved.
The system must be rebooted for this update to take effect.
—
– Scientific Linux Development Team
