USN-3469-1: Linux kernel vulnerabilities

31 October 2017

linux, linux-aws, linux-gke, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 16.04 LTS

Summary

Several security issues were fixed in the Linux kernel.

Software Description

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-gke - Linux kernel for Google Container Engine (GKE) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

Anthony Perard discovered that the Xen virtual block driver did not properly initialize some data structures before passing them to user space. A local attacker in a guest VM could use this to expose sensitive information from the host OS or other guest VMs. (CVE-2017-10911)

Bo Zhang discovered that the netlink wireless configuration interface in the Linux kernel did not properly validate attributes when handling certain requests. A local attacker with the CAP_NET_ADMIN could use this to cause a denial of service (system crash). (CVE-2017-12153)

It was discovered that the nested KVM implementation in the Linux kernel in some situations did not properly prevent second level guests from reading and writing the hardware CR8 register. A local attacker in a guest could use this to cause a denial of service (system crash).

It was discovered that the key management subsystem in the Linux kernel did not properly restrict key reads on negatively instantiated keys. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-12192)

It was discovered that an integer overflow existed in the sysfs interface for the QLogic 24xx+ series SCSI driver in the Linux kernel. A local privileged attacker could use this to cause a denial of service (system crash). (CVE-2017-14051)

It was discovered that the ATI Radeon framebuffer driver in the Linux kernel did not properly initialize a data structure returned to user space. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2017-14156)

Dave Chinner discovered that the XFS filesystem did not enforce that the realtime inode flag was settable only on filesystems on a realtime device. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-14340)

ChunYu Wang discovered that the iSCSI transport implementation in the Linux kernel did not properly validate data structures. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-14489)

It was discovered that the generic SCSI driver in the Linux kernel did not properly initialize data returned to user space in some situations. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2017-14991)

Dmitry Vyukov discovered that the Floating Point Unit (fpu) subsystem in the Linux kernel did not properly handle attempts to set reserved bits in a task’s extended state (xstate) area. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-15537)

Pengfei Wang discovered that the Turtle Beach MultiSound audio device driver in the Linux kernel contained race conditions when fetching from the ring-buffer. A local attacker could use this to cause a denial of service (infinite loop). (CVE-2017-9984, CVE-2017-9985)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 16.04 LTS
linux-image-4.4.0-1009-kvm - 4.4.0-1009.14
linux-image-4.4.0-1033-gke - 4.4.0-1033.33
linux-image-4.4.0-1039-aws - 4.4.0-1039.48
linux-image-4.4.0-1076-raspi2 - 4.4.0-1076.84
linux-image-4.4.0-1078-snapdragon - 4.4.0-1078.83
linux-image-4.4.0-98-generic - 4.4.0-98.121
linux-image-4.4.0-98-generic-lpae - 4.4.0-98.121
linux-image-4.4.0-98-lowlatency - 4.4.0-98.121
linux-image-4.4.0-98-powerpc-e500mc - 4.4.0-98.121
linux-image-4.4.0-98-powerpc-smp - 4.4.0-98.121
linux-image-4.4.0-98-powerpc64-emb - 4.4.0-98.121
linux-image-4.4.0-98-powerpc64-smp - 4.4.0-98.121
linux-image-aws - 4.4.0.1039.41
linux-image-generic - 4.4.0.98.103
linux-image-generic-lpae - 4.4.0.98.103
linux-image-gke - 4.4.0.1033.34
linux-image-kvm - 4.4.0.1009.9
linux-image-lowlatency - 4.4.0.98.103
linux-image-powerpc-e500mc - 4.4.0.98.103
linux-image-powerpc-smp - 4.4.0.98.103
linux-image-powerpc64-emb - 4.4.0.98.103
linux-image-powerpc64-smp - 4.4.0.98.103
linux-image-raspi2 - 4.4.0.1076.76
linux-image-snapdragon - 4.4.0.1078.70

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.

References