USN-4982-1: Linux kernel vulnerabilities

8 June 2021

Several security issues were fixed in the Linux kernel.

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Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-aws-5.4 - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-azure-5.4 - Linux kernel for Microsoft Azure cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gcp-5.4 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gke - Linux kernel for Google Container Engine (GKE) systems
  • linux-gke-5.4 - Linux kernel for Google Container Engine (GKE) systems
  • linux-gkeop - Linux kernel for Google Container Engine (GKE) systems
  • linux-gkeop-5.4 - Linux kernel for Google Container Engine (GKE) systems
  • linux-hwe-5.4 - Linux hardware enablement (HWE) kernel
  • linux-kvm - Linux kernel for cloud environments
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-oracle-5.4 - Linux kernel for Oracle Cloud systems
  • linux-raspi - Linux kernel for Raspberry Pi (V8) systems
  • linux-raspi-5.4 - Linux kernel for Raspberry Pi (V8) systems

Details

Kiyin (尹亮) discovered that the NFC LLCP protocol implementation in the
Linux kernel contained a reference counting error. A local attacker could
use this to cause a denial of service (system crash). (CVE-2020-25670)

Kiyin (尹亮) discovered that the NFC LLCP protocol implementation in the
Linux kernel did not properly deallocate memory in certain error
situations. A local attacker could use this to cause a denial of service
(memory exhaustion). (CVE-2020-25671, CVE-2020-25672)

Kiyin (尹亮) discovered that the NFC LLCP protocol implementation in the
Linux kernel did not properly handle error conditions in some situations,
leading to an infinite loop. A local attacker could use this to cause a
denial of service. (CVE-2020-25673)

It was discovered that the Xen paravirtualization backend in the Linux
kernel did not properly deallocate memory in some situations. A local
attacker could use this to cause a denial of service (memory exhaustion).
(CVE-2021-28688)

It was discovered that the fuse user space file system implementation in
the Linux kernel did not properly handle bad inodes in some situations. A
local attacker could possibly use this to cause a denial of service.
(CVE-2021-28950)

Zygo Blaxell discovered that the btrfs file system implementation in the
Linux kernel contained a race condition during certain cloning operations.
A local attacker could possibly use this to cause a denial of service
(system crash). (CVE-2021-28964)

Vince Weaver discovered that the perf subsystem in the Linux kernel did not
properly handle certain PEBS records properly for some Intel Haswell
processors. A local attacker could use this to cause a denial of service
(system crash). (CVE-2021-28971)

It was discovered that the RPA PCI Hotplug driver implementation in the
Linux kernel did not properly handle device name writes via sysfs, leading
to a buffer overflow. A privileged attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2021-28972)

It was discovered that the Freescale Gianfar Ethernet driver for the Linux
kernel did not properly handle receive queue overrun when jumbo frames were
enabled in some situations. An attacker could use this to cause a denial of
service (system crash). (CVE-2021-29264)

It was discovered that the Qualcomm IPC router implementation in the Linux
kernel did not properly initialize memory passed to user space. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2021-29647)

Dan Carpenter discovered that the block device manager (dm) implementation
in the Linux kernel contained a buffer overflow in the ioctl for listing
devices. A privileged local attacker could use this to cause a denial of
service (system crash). (CVE-2021-31916)

马哲宇 discovered that the IEEE 1394 (Firewire) nosy packet sniffer driver in
the Linux kernel did not properly perform reference counting in some
situations, leading to a use-after-free vulnerability. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2021-3483)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

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Update instructions

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

Ubuntu 20.04
Ubuntu 18.04

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

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