(RHSA-2014:0772) Important: kernel security and bug fix update

2014-06-19T04:00:00
ID RHSA-2014:0772
Type redhat
Reporter RedHat
Modified 2017-09-08T11:59:34

Description

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

  • A flaw was found in the way the Linux kernel's floppy driver handled user space provided data in certain error code paths while processing FDRAWCMD IOCTL commands. A local user with write access to /dev/fdX could use this flaw to free (using the kfree() function) arbitrary kernel memory. (CVE-2014-1737, Important)

  • It was found that the Linux kernel's floppy driver leaked internal kernel memory addresses to user space during the processing of the FDRAWCMD IOCTL command. A local user with write access to /dev/fdX could use this flaw to obtain information about the kernel heap arrangement. (CVE-2014-1738, Low)

Note: A local user with write access to /dev/fdX could use these two flaws (CVE-2014-1737 in combination with CVE-2014-1738) to escalate their privileges on the system.

  • A flaw was found in the way the Linux kernel's TCP/IP protocol suite implementation handled TCP packets with both the SYN and FIN flags set. A remote attacker could use this flaw to consume an excessive amount of resources on the target system, potentially resulting in a denial of service. (CVE-2012-6638, Moderate)

Red Hat would like to thank Matthew Daley for reporting CVE-2014-1737 and CVE-2014-1738.

This update also fixes the following bugs:

  • While under heavy load, some Fibre Channel storage devices, such as Hitachi and HP Open-V series, can send a logout (LOGO) message to the host system. However, due to a bug in the lpfc driver, this could result in a loss of active paths to the storage and the paths could not be recovered without manual intervention. This update corrects the lpfc driver to ensure automatic recovery of the lost paths to the storage in this scenario. (BZ#1096060)

  • A bug in the futex system call could result in an overflow when passing a very large positive timeout. As a consequence, the FUTEX_WAIT operation did not work as intended and the system call was timing out immediately. A backported patch fixes this bug by limiting very large positive timeouts to the maximal supported value. (BZ#1091831)

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.