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Ubuntu Security Notice USN-4368-1
May 19, 2020

linux-gke-5.0, linux-oem-osp1 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-gke-5.0: Linux kernel for Google Container Engine (GKE) systems
- linux-oem-osp1: Linux kernel for OEM systems

Details:

Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or expose sensitive information.
(CVE-2019-19769)

It was discovered that the Serial CAN interface driver in the Linux kernel
did not properly initialize data. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2020-11494)

It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565)

It was discovered that the OV51x USB Camera device driver in the Linux
kernel did not properly validate device metadata. A physically proximate
attacker could use this to cause a denial of service (system crash).
(CVE-2020-11608)

It was discovered that the STV06XX USB Camera device driver in the Linux
kernel did not properly validate device metadata. A physically proximate
attacker could use this to cause a denial of service (system crash).
(CVE-2020-11609)

It was discovered that the Xirlink C-It USB Camera device driver in the
Linux kernel did not properly validate device metadata. A physically
proximate attacker could use this to cause a denial of service (system
crash). (CVE-2020-11668)

David Gibson discovered that the Linux kernel on Power9 CPUs did not
properly save and restore Authority Mask registers state in some
situations. A local attacker in a guest VM could use this to cause a denial
of service (host system crash). (CVE-2020-11669)

It was discovered that the block layer in the Linux kernel contained a race
condition leading to a use-after-free vulnerability. A local attacker could
possibly use this to cause a denial of service (system crash) or execute
arbitrary code. (CVE-2020-12657)

Update instructions:

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

Ubuntu 18.04 LTS:
  linux-image-5.0.0-1037-gke      5.0.0-1037.38
  linux-image-5.0.0-1052-oem-osp1  5.0.0-1052.57
  linux-image-gke-5.0             5.0.0.1037.25
  linux-image-oem-osp1            5.0.0.1052.55

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:
  https://usn.ubuntu.com/4368-1
  CVE-2019-19769, CVE-2020-11494, CVE-2020-11565, CVE-2020-11608,
  CVE-2020-11609, CVE-2020-11668, CVE-2020-11669, CVE-2020-12657

Package Information:
  https://launchpad.net/ubuntu/+source/linux-gke-5.0/5.0.0-1037.38
  https://launchpad.net/ubuntu/+source/linux-oem-osp1/5.0.0-1052.57