[USN-5071-1] Linux kernel vulnerabilities

========================================================================== Ubuntu Security Notice USN-5071-1 September 08, 2021
linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp, linux-gcp-5.4, linux-gke, linux-gke-5.4, linux-gkeop, linux-gkeop-5.4, linux-kvm, linux-oracle, linux-oracle-5.4 vulnerabilities ==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 20.04 LTS – Ubuntu 18.04 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-azure: Linux kernel for Microsoft Azure Cloud systems – linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems – linux-gke: Linux kernel for Google Container Engine (GKE) systems – linux-gkeop: Linux kernel for Google Container Engine (GKE) systems – linux-kvm: Linux kernel for cloud environments – linux-oracle: Linux kernel for Oracle Cloud systems – linux-aws-5.4: Linux kernel for Amazon Web Services (AWS) systems – linux-azure-5.4: Linux kernel for Microsoft Azure cloud systems – linux-gcp-5.4: Linux kernel for Google Cloud Platform (GCP) systems – linux-gke-5.4: Linux kernel for Google Container Engine (GKE) systems – linux-gkeop-5.4: Linux kernel for Google Container Engine (GKE) systems – linux-oracle-5.4: Linux kernel for Oracle Cloud systems
Details:
Maxim Levitsky and Paolo Bonzini discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel allowed a guest VM to disable restrictions on VMLOAD/VMSAVE in a nested guest. An attacker in a guest VM could use this to read or write portions of the host’s physical memory. (CVE-2021-3656)
Maxim Levitsky discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not properly prevent a guest VM from enabling AVIC in nested guest VMs. An attacker in a guest VM could use this to write to portions of the host’s physical memory. (CVE-2021-3653)
It was discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not ensure enough processing time was given to perform cleanups of large SEV VMs. A local attacker could use this to cause a denial of service (soft lockup). (CVE-2020-36311)
It was discovered that the KVM hypervisor implementation in the Linux kernel did not properly perform reference counting in some situations, leading to a use-after-free vulnerability. An attacker who could start and control a VM could possibly use this to expose sensitive information or execute arbitrary code. (CVE-2021-22543)
Murray McAllister discovered that the joystick device interface in the Linux kernel did not properly validate data passed via an ioctl(). A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code on systems with a joystick device registered. (CVE-2021-3612)
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 20.04 LTS: linux-image-5.4.0-1023-gkeop 5.4.0-1023.24 linux-image-5.4.0-1046-kvm 5.4.0-1046.48 linux-image-5.4.0-1052-gcp 5.4.0-1052.56 linux-image-5.4.0-1052-gke 5.4.0-1052.55 linux-image-5.4.0-1054-oracle 5.4.0-1054.58 linux-image-5.4.0-1056-aws 5.4.0-1056.59 linux-image-5.4.0-1058-azure 5.4.0-1058.60 linux-image-5.4.0-84-generic 5.4.0-84.94 linux-image-5.4.0-84-generic-lpae 5.4.0-84.94 linux-image-5.4.0-84-lowlatency 5.4.0-84.94 linux-image-aws-lts-20.04 5.4.0.1056.59 linux-image-azure-lts-20.04 5.4.0.1058.56 linux-image-gcp-lts-20.04 5.4.0.1052.62 linux-image-generic 5.4.0.84.88 linux-image-generic-lpae 5.4.0.84.88 linux-image-gke 5.4.0.1052.62 linux-image-gke-5.4 5.4.0.1052.62 linux-image-gkeop 5.4.0.1023.26 linux-image-gkeop-5.4 5.4.0.1023.26 linux-image-kvm 5.4.0.1046.45 linux-image-lowlatency 5.4.0.84.88 linux-image-oem 5.4.0.84.88 linux-image-oem-osp1 5.4.0.84.88 linux-image-oracle-lts-20.04 5.4.0.1054.54 linux-image-virtual 5.4.0.84.88
Ubuntu 18.04 LTS: linux-image-5.4.0-1023-gkeop 5.4.0-1023.24~18.04.1 linux-image-5.4.0-1052-gcp 5.4.0-1052.56~18.04.1 linux-image-5.4.0-1052-gke 5.4.0-1052.55~18.04.1 linux-image-5.4.0-1054-oracle 5.4.0-1054.58~18.04.1 linux-image-5.4.0-1056-aws 5.4.0-1056.59~18.04.1 linux-image-5.4.0-1058-azure 5.4.0-1058.60~18.04.1 linux-image-aws 5.4.0.1056.39 linux-image-azure 5.4.0.1058.38 linux-image-gcp 5.4.0.1052.38 linux-image-gke-5.4 5.4.0.1052.55~18.04.17 linux-image-gkeop-5.4 5.4.0.1023.24~18.04.24 linux-image-oracle 5.4.0.1054.58~18.04.34
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: ubuntu.com/security/notices/USN-5071-1 CVE-2020-36311, CVE-2021-22543, CVE-2021-3612, CVE-2021-3653, CVE-2021-3656
Package Information: launchpad.net/ubuntu/+source/linux/5.4.0-84.94 launchpad.net/ubuntu/+source/linux-aws/5.4.0-1056.59 launchpad.net/ubuntu/+source/linux-azure/5.4.0-1058.60 launchpad.net/ubuntu/+source/linux-gcp/5.4.0-1052.56 launchpad.net/ubuntu/+source/linux-gke/5.4.0-1052.55 launchpad.net/ubuntu/+source/linux-gkeop/5.4.0-1023.24 launchpad.net/ubuntu/+source/linux-kvm/5.4.0-1046.48 launchpad.net/ubuntu/+source/linux-oracle/5.4.0-1054.58 launchpad.net/ubuntu/+source/linux-aws-5.4/5.4.0-1056.59~18.04.1 launchpad.net/ubuntu/+source/linux-azure-5.4/5.4.0-1058.60~18.04.1 launchpad.net/ubuntu/+source/linux-gcp-5.4/5.4.0-1052.56~18.04.1 launchpad.net/ubuntu/+source/linux-gke-5.4/5.4.0-1052.55~18.04.1 launchpad.net/ubuntu/+source/linux-gkeop-5.4/5.4.0-1023.24~18.04.1 launchpad.net/ubuntu/+source/linux-oracle-5.4/5.4.0-1054.58~18.04.1