USN-4907-1: Linux kernel vulnerabilities

13 April 2021

Several security issues were fixed in the Linux kernel.

Releases

Packages

Details

Wen Xu discovered that the xfs file system implementation in the Linux
kernel did not properly validate the number of extents in an inode. An
attacker could use this to construct a malicious xfs image that, when
mounted, could cause a denial of service (system crash). (CVE-2018-13095)

It was discovered that the priority inheritance futex implementation in the
Linux kernel contained a race condition, 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-2021-3347)

It was discovered that the network block device (nbd) driver in the Linux
kernel contained a use-after-free vulnerability during device setup. A
local attacker with access to the nbd device could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2021-3348)

Update instructions

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

Ubuntu 18.04
Ubuntu 16.04
Ubuntu 14.04

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.

Related notices

  • USN-4904-1: linux-image-generic-lpae-lts-xenial, linux-image-virtual-lts-utopic, linux-image-generic-lpae-lts-wily, linux-image-powerpc-e500mc-lts-vivid, linux-image-virtual-lts-wily, linux-kvm, linux-image-kvm, linux-image-aws, linux-image-4.4.0-208-powerpc64-emb, linux-image-lowlatency-lts-wily, linux-image-powerpc64-smp-lts-utopic, linux-image-powerpc64-smp, linux-image-generic-lts-wily, linux-image-generic-lts-xenial, linux-image-virtual, linux-image-powerpc-e500mc-lts-wily, linux-image-lowlatency-lts-utopic, linux-image-4.4.0-1090-aws, linux-image-4.4.0-1154-snapdragon, linux-raspi2, linux, linux-image-powerpc64-smp-lts-wily, linux-image-generic-lpae-lts-vivid, linux-image-4.4.0-1091-kvm, linux-image-generic, linux-image-raspi2, linux-image-powerpc64-emb, linux-image-4.4.0-208-generic, linux-image-4.4.0-208-generic-lpae, linux-image-generic-lpae-lts-utopic, linux-image-powerpc64-emb-lts-vivid, linux-image-powerpc-smp, linux-image-lowlatency-lts-xenial, linux-lts-xenial, linux-image-powerpc-e500mc, linux-image-powerpc-smp-lts-utopic, linux-image-4.4.0-208-powerpc-smp, linux-image-powerpc64-emb-lts-xenial, linux-image-4.4.0-208-powerpc64-smp, linux-image-generic-lpae, linux-image-powerpc-smp-lts-wily, linux-image-lowlatency-lts-vivid, linux-image-4.4.0-1150-raspi2, linux-snapdragon, linux-image-powerpc64-smp-lts-xenial, linux-image-4.4.0-208-powerpc-e500mc, linux-image-4.4.0-208-lowlatency, linux-image-powerpc64-emb-lts-utopic, linux-image-powerpc64-emb-lts-wily, linux-image-virtual-lts-xenial, linux-image-generic-lts-utopic, linux-image-generic-lts-vivid, linux-image-powerpc-e500mc-lts-xenial, linux-image-powerpc-smp-lts-vivid, linux-image-snapdragon, linux-image-virtual-lts-vivid, linux-image-powerpc-e500mc-lts-utopic, linux-image-powerpc-smp-lts-xenial, linux-aws, linux-image-powerpc64-smp-lts-vivid, linux-image-lowlatency, linux-image-4.4.0-1126-aws
  • USN-4910-1: linux-kvm, linux-image-kvm, linux-image-aws, linux-image-5.8.0-1025-oracle, linux-image-5.8.0-1027-gcp, linux-image-oem-20.04, linux-gcp, linux-image-virtual-hwe-20.04-edge, linux-image-5.8.0-49-generic-lpae, linux-image-virtual, linux-image-gke, linux-image-lowlatency-hwe-20.04, linux-image-oracle, linux, linux-image-lowlatency-hwe-20.04-edge, linux-image-generic, linux-azure, linux-image-generic-64k, linux-image-5.8.0-1020-raspi-nolpae, linux-image-5.8.0-1028-aws, linux-oracle, linux-hwe-5.8, linux-image-azure, linux-image-generic-hwe-20.04-edge, linux-image-5.8.0-1020-raspi, linux-image-generic-lpae, linux-image-5.8.0-49-generic-64k, linux-image-5.8.0-49-lowlatency, linux-image-generic-64k-hwe-20.04, linux-image-raspi-nolpae, linux-raspi, linux-image-5.8.0-1027-azure, linux-image-gcp, linux-image-generic-64k-hwe-20.04-edge, linux-image-generic-lpae-hwe-20.04, linux-image-raspi, linux-image-virtual-hwe-20.04, linux-image-generic-lpae-hwe-20.04-edge, linux-image-5.8.0-1023-kvm, linux-image-generic-hwe-20.04, linux-aws, linux-image-5.8.0-49-generic, linux-image-lowlatency
  • USN-4878-1: linux-image-5.4.0-1011-gkeop, linux-image-snapdragon-hwe-18.04-edge, linux-gkeop, linux-image-5.4.0-67-generic, linux-image-gke-5.4, linux-image-raspi2-hwe-18.04, linux-image-raspi2-hwe-18.04-edge, linux-kvm, linux-image-kvm, linux-image-aws, linux-image-5.4.0-1039-oracle, linux-image-5.4.0-1030-raspi, linux-gcp, linux-image-generic-lpae-hwe-18.04, linux-image-lowlatency-hwe-18.04, linux-image-5.4.0-1034-kvm, linux-image-gkeop-5.4, linux-image-virtual, linux-image-virtual-hwe-18.04, linux-raspi-5.4, linux-image-5.4.0-1041-azure, linux-gcp-5.4, linux-image-oracle, linux, linux-image-snapdragon-hwe-18.04, linux-image-raspi2, linux-image-generic, linux-azure, linux-azure-5.4, linux-image-5.4.0-1038-gcp, linux-image-raspi-hwe-18.04-edge, linux-oracle, linux-hwe-5.4, linux-image-aws-edge, linux-image-azure, linux-gkeop-5.4, linux-image-gcp-edge, linux-image-generic-lpae-hwe-18.04-edge, linux-image-lowlatency-hwe-18.04-edge, linux-image-generic-hwe-18.04, linux-image-gkeop, linux-image-5.4.0-1037-gke, linux-image-generic-lpae, linux-image-oracle-edge, linux-image-5.4.0-67-lowlatency, linux-image-raspi-hwe-18.04, linux-aws-5.4, linux-raspi, linux-image-gcp, linux-gke-5.4, linux-image-raspi, linux-image-generic-hwe-18.04-edge, linux-image-5.4.0-1039-aws, linux-image-5.4.0-67-generic-lpae, linux-image-virtual-hwe-18.04-edge, linux-image-oem-osp1, linux-image-oem, linux-aws, linux-image-azure-edge, linux-image-lowlatency, linux-oracle-5.4
  • USN-4909-1: linux-image-snapdragon-hwe-18.04-edge, linux-gkeop, linux-image-raspi2-hwe-18.04-edge, linux-image-azure-edge, linux-image-gke-5.4, linux-image-raspi2-hwe-18.04, linux-kvm, linux-image-kvm, linux-image-aws, linux-gcp, linux-image-generic-lpae-hwe-18.04, linux-image-lowlatency-hwe-18.04, linux-image-gkeop-5.4, linux-image-5.4.0-1043-aws, linux-image-5.4.0-1044-azure, linux-image-5.4.0-1033-raspi, linux-image-virtual, linux-gcp-5.4, linux-image-virtual-hwe-18.04, linux-raspi-5.4, linux-image-5.4.0-1042-oracle, linux-image-oracle, linux, linux-image-snapdragon-hwe-18.04, linux-image-raspi2, linux-image-5.4.0-1040-gke, linux-image-generic, linux-azure, linux-azure-5.4, linux-image-raspi-hwe-18.04-edge, linux-image-5.4.0-1013-gkeop, linux-image-5.4.0-1037-kvm, linux-oracle, linux-hwe-5.4, linux-image-aws-edge, linux-image-azure, linux-gkeop-5.4, linux-image-5.4.0-71-generic, linux-image-gcp-edge, linux-image-generic-lpae-hwe-18.04-edge, linux-image-lowlatency-hwe-18.04-edge, linux-image-generic-hwe-18.04, linux-image-gkeop, linux-image-generic-lpae, linux-image-oracle-edge, linux-image-raspi-hwe-18.04, linux-aws-5.4, linux-raspi, linux-image-5.4.0-71-generic-lpae, linux-image-gcp, linux-gke-5.4, linux-image-raspi, linux-image-generic-hwe-18.04-edge, linux-image-5.4.0-1041-gcp, linux-image-virtual-hwe-18.04-edge, linux-image-oem-osp1, linux-image-oem, linux-aws, linux-image-5.4.0-71-lowlatency, linux-image-lowlatency, linux-oracle-5.4
  • USN-4884-1: linux-oem-5.10, linux-image-oem-20.04b, linux-image-5.10.0-1017-oem, linux-image-oem-20.04-edge