USN-3392-2: Linux kernel (Xenial HWE) regression
16 August 2017
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 14.04 LTS
USN-3378-2 introduced a regression the Linux Hardware Enablement kernel.
- linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty
USN-3392-1 fixed a regression in the Linux kernel for Ubuntu 16.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu 14.04 LTS.
USN-3378-2 fixed vulnerabilities in the Linux Hardware Enablement kernel. Unfortunately, a regression was introduced that prevented conntrack from working correctly in some situations. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Fan Wu and Shixiong Zhao discovered a race condition between inotify events and vfs rename operations in the Linux kernel. An unprivileged local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2017-7533)
It was discovered that the Linux kernel did not properly restrict RLIMIT_STACK size. A local attacker could use this in conjunction with another vulnerability to possibly execute arbitrary code. (CVE-2017-1000365)
李强 discovered that the Virtio GPU driver in the Linux kernel did not properly free memory in some situations. A local attacker could use this to cause a denial of service (memory consumption). (CVE-2017-10810)
石磊 discovered that the RxRPC Kerberos 5 ticket handling code in the Linux kernel did not properly verify metadata. A remote attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-7482)
The problem can be corrected by updating your system to the following package versions:
- Ubuntu 14.04 LTS
- linux-image-4.4.0-92-generic - 4.4.0-92.115~14.04.1
- linux-image-4.4.0-92-generic-lpae - 4.4.0-92.115~14.04.1
- linux-image-4.4.0-92-lowlatency - 4.4.0-92.115~14.04.1
- linux-image-4.4.0-92-powerpc-e500mc - 4.4.0-92.115~14.04.1
- linux-image-4.4.0-92-powerpc-smp - 4.4.0-92.115~14.04.1
- linux-image-4.4.0-92-powerpc64-emb - 4.4.0-92.115~14.04.1
- linux-image-4.4.0-92-powerpc64-smp - 4.4.0-92.115~14.04.1
- linux-image-generic-lpae-lts-xenial - 22.214.171.124.76
- linux-image-generic-lts-xenial - 126.96.36.199.76
- linux-image-lowlatency-lts-xenial - 188.8.131.52.76
- linux-image-powerpc-e500mc-lts-xenial - 184.108.40.206.76
- linux-image-powerpc-smp-lts-xenial - 220.127.116.11.76
- linux-image-powerpc64-emb-lts-xenial - 18.104.22.168.76
- linux-image-powerpc64-smp-lts-xenial - 22.214.171.124.76
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.
ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well.