Synopsis: Moderate: kernel security and bug fix update
Advisory ID: SLSA-2014:0108-1
Issue Date: 2014-01-29
CVE Numbers: CVE-2013-4494
* It was found that the Xen hypervisor did not always lock
‘page_alloc_lock’ and ‘grant_table.lock’ in the same order. This could
potentially lead to a deadlock. A malicious guest administrator could use
this flaw to cause a denial of service on the host. (CVE-2013-4494,
This update also fixes the following bugs:
* A recent patch to the CIFS code that introduced the NTLMSSP (NT LAN
Manager Security Support Provider) authentication mechanism caused a
regression in CIFS behavior. As a result of the regression, an encryption
key that is returned during the SMB negotiation protocol response was only
used for the first session that was created on the SMB client. Any
subsequent mounts to the same server did not use the encryption key
returned by the initial negotiation with the server. As a consequence, it
was impossible to mount multiple SMB shares with different credentials to
the same server. A patch has been applied to correct this problem so that
an encryption key or a server challenge is now provided for every SMB
session during the SMB negotiation protocol response.
* The igb driver previously used a 16-bit mask when writing values of the
flow control high-water mark to hardware registers on a network device.
Consequently, the values were truncated on some network devices,
disrupting the flow control. A patch has been applied to the igb driver so
that it now uses a 32-bit mask as expected.
* The IPMI driver did not properly handle kernel panic messages.
Consequently, when a kernel panic occurred on a system that was utilizing
IPMI without Kdump being set up, a second kernel panic could be triggered.
A patch has been applied to the IPMI driver to fix this problem, and a
message handler now properly waits for a response to panic event messages.
The system must be rebooted for this update to take effect.
– Scientific Linux Development Team