CVE-2026-93096

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: cxl/features: Serialize multi-part Get/Set Feature transfers A Get or Set Feature payload larger than the mailbox payload size is split into several mailbox commands. mbox_mutex only serializes individual mailbox commands and is dropped between iterations of these loops. Nothing serializes the multi-part transfer as a whole. cxl_get_feature() and cxl_set_feature() are reachable concurrently from fwctl (per-fd RPCs run under a read-held registration lock) and from the EDAC scrub/ECS/repair paths, so two transfers to the same mailbox can interleave their parts and corrupt the device's transfer context. Add a per-mailbox feat_mutex and hold it across the whole transfer in both functions. It nests outside mbox_mutex (which is taken inside cxl_internal_send_cmd()), and is taken nowhere else, so no lock-ordering inversion is introduced.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-17 17:18:03.713000

Last modified

2026-10-19 10:16:59.410000

View original CVE JSON

{
  "id": "CVE-2026-93096",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:18:03.713",
  "lastModified": "2026-10-19T10:16:59.410",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncxl/features: Serialize multi-part Get/Set Feature transfers\n\nA Get or Set Feature payload larger than the mailbox payload size is\nsplit into several mailbox commands. mbox_mutex only serializes\nindividual mailbox commands and is dropped between iterations of these\nloops. Nothing serializes the multi-part transfer as a whole.\ncxl_get_feature() and cxl_set_feature() are reachable concurrently\nfrom fwctl (per-fd RPCs run under a read-held registration lock) and\nfrom the EDAC scrub/ECS/repair paths, so two transfers to the same\nmailbox can interleave their parts and corrupt the device's transfer\ncontext.\n\nAdd a per-mailbox feat_mutex and hold it across the whole transfer in\nboth functions. It nests outside mbox_mutex (which is taken inside\ncxl_internal_send_cmd()), and is taken nowhere else, so no lock-ordering\ninversion is introduced."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/cxl/core/features.c",
            "drivers/cxl/core/mbox.c",
            "include/cxl/mailbox.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5e5ac21f629de796ab5d598b59c5e468c6fe4f95",
              "lessThan": "c6492e17412048387435f256ffafc4dd6518db28",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5e5ac21f629de796ab5d598b59c5e468c6fe4f95",
              "lessThan": "7682b617db1f19bc606b5f1badadcf1e63a87b14",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5e5ac21f629de796ab5d598b59c5e468c6fe4f95",
              "lessThan": "77b814c1832fde018c30357b4ec3fcdaa91a1c10",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/cxl/core/features.c",
            "drivers/cxl/core/mbox.c",
            "include/cxl/mailbox.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.15",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.15",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.57",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/7682b617db1f19bc606b5f1badadcf1e63a87b14",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/77b814c1832fde018c30357b4ec3fcdaa91a1c10",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c6492e17412048387435f256ffafc4dd6518db28",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}