CVE-2026-64472 (GCVE-0-2026-64472)
Vulnerability from cvelistv5
Published
2026-07-25 08:51
Modified
2026-08-17 04:56
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: vfio/mlx5: Fix racy bitfields and tighten struct layout Bitfield operations are not atomic, they use a read-modify-write pattern, therefore we should be careful not to pack bitfields that can be concurrently updated into the same storage unit. This split takes a binary approach: flags that are only modified pre/post open/close remain bitfields, flags modified from user action, including actions that reach across to another device (ex. reset) use dedicated storage units. Note mlx5_vhca_page_tracker.status is relocated to fill the alignment hole this split exposes. Bitfield justifications: migrate_cap: written only in mlx5vf_cmd_set_migratable() at probe chunk_mode: written only in mlx5vf_cmd_set_migratable() at probe mig_state_cap: written only in mlx5vf_cmd_set_migratable() at probe Dedicated storage units: mdev_detach: written in the VF attach/detach event notifier mlx5fv_vf_event() at runtime log_active: written in mlx5vf_start_page_tracker()/ mlx5vf_stop_page_tracker() during runtime dirty tracking deferred_reset: written in mlx5vf_state_mutex_unlock()/ mlx5vf_pci_aer_reset_done() during runtime reset handling is_err: set by tracker error handling and dirty-log polling at runtime object_changed: set by tracker event handling and cleared by dirty-log polling at runtime
References
Impacted products
Vendor Product Version
Linux Linux Version: 61a2f1460fd03285ea34c1a235f2f50f71e13a1f
Version: 61a2f1460fd03285ea34c1a235f2f50f71e13a1f
Version: 61a2f1460fd03285ea34c1a235f2f50f71e13a1f
Version: 61a2f1460fd03285ea34c1a235f2f50f71e13a1f
Version: 61a2f1460fd03285ea34c1a235f2f50f71e13a1f
Version: 61a2f1460fd03285ea34c1a235f2f50f71e13a1f
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/vfio/pci/mlx5/cmd.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "1dd99b8f4e143592e12e5a77e7b538bc698116cb",
              "status": "affected",
              "version": "61a2f1460fd03285ea34c1a235f2f50f71e13a1f",
              "versionType": "git"
            },
            {
              "lessThan": "f1db80a67da928a92ba460ede1be52d8941f46be",
              "status": "affected",
              "version": "61a2f1460fd03285ea34c1a235f2f50f71e13a1f",
              "versionType": "git"
            },
            {
              "lessThan": "399d806f998f7a25405fc1b97227e579aead24af",
              "status": "affected",
              "version": "61a2f1460fd03285ea34c1a235f2f50f71e13a1f",
              "versionType": "git"
            },
            {
              "lessThan": "7ed120b1a007bace57c461805519d70e1af44e59",
              "status": "affected",
              "version": "61a2f1460fd03285ea34c1a235f2f50f71e13a1f",
              "versionType": "git"
            },
            {
              "lessThan": "39d163627b51886492bf31f66cb02c94613d2287",
              "status": "affected",
              "version": "61a2f1460fd03285ea34c1a235f2f50f71e13a1f",
              "versionType": "git"
            },
            {
              "lessThan": "f2365a63b02ddea32e7db78b742c2503ec7b81f1",
              "status": "affected",
              "version": "61a2f1460fd03285ea34c1a235f2f50f71e13a1f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/vfio/pci/mlx5/cmd.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.19"
            },
            {
              "lessThan": "5.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.4",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/mlx5: Fix racy bitfields and tighten struct layout\n\nBitfield operations are not atomic, they use a read-modify-write\npattern, therefore we should be careful not to pack bitfields that\ncan be concurrently updated into the same storage unit.\n\nThis split takes a binary approach: flags that are only modified\npre/post open/close remain bitfields, flags modified from user\naction, including actions that reach across to another device (ex.\nreset) use dedicated storage units.\n\nNote mlx5_vhca_page_tracker.status is relocated to fill the alignment\nhole this split exposes.\n\nBitfield justifications:\n\n  migrate_cap: written only in mlx5vf_cmd_set_migratable() at probe\n  chunk_mode: written only in mlx5vf_cmd_set_migratable() at probe\n  mig_state_cap: written only in mlx5vf_cmd_set_migratable() at probe\n\nDedicated storage units:\n\n  mdev_detach: written in the VF attach/detach event notifier\n               mlx5fv_vf_event() at runtime\n  log_active: written in mlx5vf_start_page_tracker()/\n              mlx5vf_stop_page_tracker() during runtime dirty tracking\n  deferred_reset: written in mlx5vf_state_mutex_unlock()/\n                  mlx5vf_pci_aer_reset_done() during runtime reset handling\n  is_err: set by tracker error handling and dirty-log polling at runtime\n  object_changed: set by tracker event handling and cleared by dirty-log\n                  polling at runtime"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:56:18.199Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/1dd99b8f4e143592e12e5a77e7b538bc698116cb"
        },
        {
          "url": "https://git.kernel.org/stable/c/f1db80a67da928a92ba460ede1be52d8941f46be"
        },
        {
          "url": "https://git.kernel.org/stable/c/399d806f998f7a25405fc1b97227e579aead24af"
        },
        {
          "url": "https://git.kernel.org/stable/c/7ed120b1a007bace57c461805519d70e1af44e59"
        },
        {
          "url": "https://git.kernel.org/stable/c/39d163627b51886492bf31f66cb02c94613d2287"
        },
        {
          "url": "https://git.kernel.org/stable/c/f2365a63b02ddea32e7db78b742c2503ec7b81f1"
        }
      ],
      "title": "vfio/mlx5: Fix racy bitfields and tighten struct layout",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64472",
    "datePublished": "2026-07-25T08:51:35.978Z",
    "dateReserved": "2026-07-19T15:36:31.790Z",
    "dateUpdated": "2026-08-17T04:56:18.199Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.