CVE-2026-93075

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: dax/fsdev: clear pgmap ops and owner on unbind fsdev_dax_probe() sets pgmap->ops = &fsdev_pagemap_ops and pgmap->owner = dev_dax, but nothing ever clears them. For a dynamic device the pgmap is devm-allocated and freed on unbind, so this is harmless. For a static device the pgmap is the shared, long-lived one owned by the dax bus (kill_dev_dax() only NULLs dev_dax->pgmap for the non-static case), and device.c's probe sets only pgmap->type, never clearing ops/owner. So after fsdev unbinds a static device the stale fsdev_pagemap_ops survives on the shared pgmap. If the device is then rebound to device_dax (MEMORY_DEVICE_GENERIC, which installs no ->memory_failure), or the fsdev_dax module is unloaded, a subsequent memory_failure on that pgmap dispatches through the stale -- and possibly freed -- handler. Register a devm action that clears pgmap->ops and pgmap->owner on unbind, symmetric with setting them at probe, so the pgmap carries no fsdev state once fsdev is detached.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

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

Published

2026-09-17 17:18:01.440000

Last modified

2026-10-19 10:16:57.470000

View original CVE JSON

{
  "id": "CVE-2026-93075",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:18:01.440",
  "lastModified": "2026-10-19T10:16:57.470",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndax/fsdev: clear pgmap ops and owner on unbind\n\nfsdev_dax_probe() sets pgmap->ops = &fsdev_pagemap_ops and\npgmap->owner = dev_dax, but nothing ever clears them. For a dynamic\ndevice the pgmap is devm-allocated and freed on unbind, so this is\nharmless. For a static device the pgmap is the shared, long-lived one\nowned by the dax bus (kill_dev_dax() only NULLs dev_dax->pgmap for the\nnon-static case), and device.c's probe sets only pgmap->type, never\nclearing ops/owner.\n\nSo after fsdev unbinds a static device the stale fsdev_pagemap_ops\nsurvives on the shared pgmap. If the device is then rebound to\ndevice_dax (MEMORY_DEVICE_GENERIC, which installs no ->memory_failure),\nor the fsdev_dax module is unloaded, a subsequent memory_failure on that\npgmap dispatches through the stale -- and possibly freed -- handler.\n\nRegister a devm action that clears pgmap->ops and pgmap->owner on unbind,\nsymmetric with setting them at probe, so the pgmap carries no fsdev state\nonce fsdev is detached."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/dax/fsdev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "d5406bd458b0ac10b1301a4d5801d85c8f648637",
              "lessThan": "9b0f91dc9147a8601cec3d4d83cf13c6aaf71b27",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d5406bd458b0ac10b1301a4d5801d85c8f648637",
              "lessThan": "f48884ac31b6bfc99f36b3f207b8c0cbe5d54bd7",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/dax/fsdev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "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/9b0f91dc9147a8601cec3d4d83cf13c6aaf71b27",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f48884ac31b6bfc99f36b3f207b8c0cbe5d54bd7",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}