Synopsis: Moderate: kernel security and bug fix update
Advisory ID: SLSA-2013:1292-1
Issue Date: 2013-09-26
CVE Numbers: CVE-2012-3511
This update fixes the following security issues:
* A use-after-free flaw was found in the madvise() system call
implementation in the Linux kernel. A local, unprivileged user could use
this flaw to cause a denial of service or, potentially, escalate their
privileges. (CVE-2012-3511, Moderate)
* A flaw was found in the way the Linux kernel’s TCP/IP protocol suite
implementation handled IPv6 sockets that used the UDP_CORK option. A
local, unprivileged user could use this flaw to cause a denial of service.
* An information leak flaw in the Linux kernel could allow a local,
unprivileged user to leak kernel memory to user-space. (CVE-2013-2141,
This update also fixes the following bugs:
* A bug in the be2net driver prevented communication between NICs using
be2net. This update applies a patch addressing this problem along with
several other upstream patches that fix various other problems. Traffic
between NICs using the be2net driver now proceeds as expected.
* A recent patch fixing a problem that prevented communication between
NICs using the be2net driver caused the firmware of NICs to become
unresponsive, and thus triggered a kernel panic. The problem was caused by
unnecessary usage of a hardware workaround that allows skipping VLAN tag
insertion. A patch has been applied and the workaround is now used only
when the multi-channel configuration is enabled on the NIC. Note that the
bug only affected the NICs with firmware version 4.2.xxxx.
* A bug in the autofs4 mount expiration code could cause the autofs4
module to falsely report a busy tree of NFS mounts as “not in use”.
Consequently, automount attempted to unmount the tree and failed with a
“failed to umount offset” error, leaving the mount tree to appear as empty
directories. A patch has been applied to remove an incorrectly used autofs
dentry mount check and the aforementioned problem no longer occurs.
* A race condition in the be_open function in the be2net driver could
trigger the BUG_ON() macro, which resulted in a kernel panic. A patch
addressing this problem has been applied and the race condition is now
avoided by enabling polling before enabling interrupts globally. The
kernel no longer panics in this situation.
The system must be rebooted for this update to take effect.
– Scientific Linux Development Team