CVE-2026-89940

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: iio: buffer: Tie IIO dma fence lock lifetime to the fence The `iio_dma_fence` implementation currently uses a lock embedded in the `iio_dmabuf_priv`. But the `iio_dma_fence` can outlive the `iio_dmabuf_priv`, which can cause a use-after-free. Tie the lifetime of the lock to the lifetime of the fence by embedding them in the same struct. We can't just hold a reference to the `iio_dmabuf_priv` from the `iio_dma_fence` since `iio_buffer_dmabuf_release()` might sleep and the fence release callback is not allowed to sleep. Note that the `dma_fence` framework now has an internal lock that gets used when the passing `NULL` for `lock` in `dma_fence_init()`, but in order to allow this patch to be backportable use an external lock.

Severity

HIGH

CVSS score

7.8 (v3.1)

Vulnerability status

Received

Source identifier

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

Published

2026-09-16 11:17:03.610000

Last modified

2026-10-19 09:18:39.800000

View original CVE JSON

{
  "id": "CVE-2026-89940",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:17:03.610",
  "lastModified": "2026-10-19T09:18:39.800",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niio: buffer: Tie IIO dma fence lock lifetime to the fence\n\nThe `iio_dma_fence` implementation currently uses a lock embedded in the\n`iio_dmabuf_priv`. But the `iio_dma_fence` can outlive the\n`iio_dmabuf_priv`, which can cause a use-after-free.\n\nTie the lifetime of the lock to the lifetime of the fence by embedding them\nin the same struct.\n\nWe can't just hold a reference to the `iio_dmabuf_priv` from the\n`iio_dma_fence` since `iio_buffer_dmabuf_release()` might sleep and the\nfence release callback is not allowed to sleep.\n\nNote that the `dma_fence` framework now has an internal lock that gets used\nwhen the passing `NULL` for `lock` in `dma_fence_init()`, but in order to\nallow this patch to be backportable use an external lock."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/iio/industrialio-buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f",
              "lessThan": "6865d79fca17a80fbd60c12550ca9a5e0e20e0eb",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f",
              "lessThan": "510497e31be4f241103507315a859e2085ccb081",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f",
              "lessThan": "8b3e221590181a8beb3735bbabf166df02c839b5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f",
              "lessThan": "f25ec4627d935dedfb5fe83bd2c2678cdcc19611",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/iio/industrialio-buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.11",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.11",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.51",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.5",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/510497e31be4f241103507315a859e2085ccb081",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6865d79fca17a80fbd60c12550ca9a5e0e20e0eb",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8b3e221590181a8beb3735bbabf166df02c839b5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f25ec4627d935dedfb5fe83bd2c2678cdcc19611",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}