x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.
Advisories
Source ID Title
Debian DSA Debian DSA DSA-5184-1 xen security update
EUVD EUVD EUVD-2022-30921 x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.
Fixes

Solution

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Workaround

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cve-icon MITRE

Status: PUBLISHED

Assigner: XEN

Published:

Updated: 2024-08-03T05:03:32.792Z

Reserved: 2022-03-02T00:00:00

Link: CVE-2022-26362

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2022-06-09T17:15:08.957

Modified: 2024-11-21T06:53:49.957

Link: CVE-2022-26362

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

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Weaknesses