CVE-2021-47450

Source
https://nvd.nist.gov/vuln/detail/CVE-2021-47450
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47450.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-47450
Related
Published
2024-05-22T07:15:10Z
Modified
2024-09-18T01:00:20Z
Summary
[none]
Details

In the Linux kernel, the following vulnerability has been resolved:

KVM: arm64: Fix host stage-2 PGD refcount

The KVM page-table library refcounts the pages of concatenated stage-2 PGDs individually. However, when running KVM in protected mode, the host's stage-2 PGD is currently managed by EL2 as a single high-order compound page, which can cause the refcount of the tail pages to reach 0 when they shouldn't, hence corrupting the page-table.

Fix this by introducing a new hypsplitpage() helper in the EL2 page allocator (matching the kernel's splitpage() function), and make use of it from hosts2zallocpages_exact().

References

Affected packages

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.15.3-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.15.3-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}