USN-2643-2: Linux kernel regression
21 June 2015
linux regression
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 14.04 LTS
Summary
The system could be made to crash under certain conditions.
Software Description
- linux - Linux kernel
Details
The Fix for CVE-2015-1328 introduced a regression into the Linux kernel’s overlayfs file system. The removal of a directory that only exists on the lower layer results in a kernel panic.
We apologize for the inconvenience.
Original advisory details:
Philip Pettersson discovered a privilege escalation when using overlayfs mounts inside of user namespaces. A local user could exploit this flaw to gain administrative privileges on the system.
Update instructions
The problem can be corrected by updating your system to the following package versions:
- Ubuntu 14.04 LTS
- linux-image-3.13.0-55-generic - 3.13.0-55.94
- linux-image-3.13.0-55-generic-lpae - 3.13.0-55.94
- linux-image-3.13.0-55-lowlatency - 3.13.0-55.94
- linux-image-3.13.0-55-powerpc-e500 - 3.13.0-55.94
- linux-image-3.13.0-55-powerpc-e500mc - 3.13.0-55.94
- linux-image-3.13.0-55-powerpc-smp - 3.13.0-55.94
- linux-image-3.13.0-55-powerpc64-emb - 3.13.0-55.94
- linux-image-3.13.0-55-powerpc64-smp - 3.13.0-55.94
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.