CVE-2023-46835
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2023-46835
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-46835.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2023-46835
- Downstream
- Related
- Published
- 2024-01-05T17:15:11Z
- Modified
- 2025-08-09T19:01:29Z
- Severity
-
- 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
- Summary
- [none]
- Details
-
The current setup of the quarantine page tables assumes that the quarantine domain (domio) has been initialized with an address width of DEFAULTDOMAINADDRESSWIDTH (48) and hence 4 page table levels.
However dom_io being a PV domain gets the AMD-Vi IOMMU page tables levels based on the maximum (hot pluggable) RAM address, and hence on systems with no RAM above the 512GB mark only 3 page-table levels are configured in the IOMMU.
On systems without RAM above the 512GB boundary amdiommuquarantine_init() will setup page tables for the scratch page with 4 levels, while the IOMMU will be configured to use 3 levels only, resulting in the last page table directory (PDE) effectively becoming a page table entry (PTE), and hence a device in quarantine mode gaining write access to the page destined to be a PDE.
Due to this page table level mismatch, the sink page the device gets read/write access to is no longer cleared between device assignment, possibly leading to data leaks.
- References