iommu/vt-d: Fix race condition during PASID entry replacement
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix race condition during PASID entry replacement The Intel VT-d PASID table entry is 512 bits (64 bytes). When replacing an active PASID entry (e.g., during domain replacement), the current implementation calculates a new entry on the stack and copies it to the table using a single structure assignment. struct pasid_entry *pte, new_pte; pte = intel_pasid_get_entry(dev, pasid); pasid_pte_config_first_level(iommu, &new_pte, ...); *pte = new_pte; Because the hardware may fetch the 512-bit PASID entry in multiple 128-bit chunks, updating the entire entry while it is active (Present bit set) risks a "torn" read. In this scenario, the IOMMU hardware could observe an inconsistent state — partially new data and partially old data — leading to unpredictable behavior or spurious faults. Fix this by removing the unsafe "replace" helpers and following the "clear-then-update" flow, which ensures the Present bit is cleared and the required invalidation handshake is completed before the new configuration is applied.
CVE-2026-45945
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-45945
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7543ee63e8113aa34b07df3b16b3b9d2c5f73939",
"lessThan": "4718007870547e1efebbdd6745d9fce58f008fef",
"versionType": "git"
},
{
"status": "affected",
"version": "7543ee63e8113aa34b07df3b16b3b9d2c5f73939",
"lessThan": "66a7aff480a82b8642b3991fed5fdc9780022157",
"versionType": "git"
},
{
"status": "affected",
"version": "7543ee63e8113aa34b07df3b16b3b9d2c5f73939",
"lessThan": "c3b1edea3791fa91ab7032faa90355913ad9451b",
"versionType": "git"
}
],
"programFiles": [
"drivers/iommu/intel/iommu.c",
"drivers/iommu/intel/nested.c",
"drivers/iommu/intel/pasid.c",
"drivers/iommu/intel/pasid.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.13"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.13",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.4",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/iommu/intel/iommu.c",
"drivers/iommu/intel/nested.c",
"drivers/iommu/intel/pasid.c",
"drivers/iommu/intel/pasid.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-45945
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40096 · Revision 1
- Added to Heist Feed
- Publisher date