CVE-2025-39999 (GCVE-0-2025-39999)

Vulnerability from cvelistv5 – Published: 2025-10-15 07:58 – Updated: 2026-05-23 16:01
VLAI
Title
blk-mq: fix blk_mq_tags double free while nr_requests grown
Summary
In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix blk_mq_tags double free while nr_requests grown In the case user trigger tags grow by queue sysfs attribute nr_requests, hctx->sched_tags will be freed directly and replaced with a new allocated tags, see blk_mq_tag_update_depth(). The problem is that hctx->sched_tags is from elevator->et->tags, while et->tags is still the freed tags, hence later elevator exit will try to free the tags again, causing kernel panic. Fix this problem by replacing et->tags with new allocated tags as well. Noted there are still some long term problems that will require some refactor to be fixed thoroughly[1]. [1] https://lore.kernel.org/all/20250815080216.410665-1-yukuai1@huaweicloud.com/
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6843 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 58567d8e95c096ad234963df90a2ca518901f4b6 , < 8faee580d63bc2a54a59dcdb7f9ce4de29384fec (git)
Affected: f5a6604f7a4405450e4a1f54e5430f47290c500f , < 392b1d64911f4de8887fe8b68299fa8bd6e5b923 (git)
Affected: f5a6604f7a4405450e4a1f54e5430f47290c500f , < ba28afbd9eff2a6370f23ef4e6a036ab0cfda409 (git)
Affected: 6.16.4 , < 6.16.11 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 6.17
Unaffected: 0 , < 6.17 (semver)
Unaffected: 6.16.11 , ≤ 6.16.* (semver)
Unaffected: 6.17.1 , ≤ 6.17.* (semver)
Unaffected: 6.18 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "block/blk-mq-tag.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8faee580d63bc2a54a59dcdb7f9ce4de29384fec",
              "status": "affected",
              "version": "58567d8e95c096ad234963df90a2ca518901f4b6",
              "versionType": "git"
            },
            {
              "lessThan": "392b1d64911f4de8887fe8b68299fa8bd6e5b923",
              "status": "affected",
              "version": "f5a6604f7a4405450e4a1f54e5430f47290c500f",
              "versionType": "git"
            },
            {
              "lessThan": "ba28afbd9eff2a6370f23ef4e6a036ab0cfda409",
              "status": "affected",
              "version": "f5a6604f7a4405450e4a1f54e5430f47290c500f",
              "versionType": "git"
            },
            {
              "lessThan": "6.16.11",
              "status": "affected",
              "version": "6.16.4",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "block/blk-mq-tag.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.17"
            },
            {
              "lessThan": "6.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.16.*",
              "status": "unaffected",
              "version": "6.16.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.1",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16.11",
                  "versionStartIncluding": "6.16.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17.1",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblk-mq: fix blk_mq_tags double free while nr_requests grown\n\nIn the case user trigger tags grow by queue sysfs attribute nr_requests,\nhctx-\u003esched_tags will be freed directly and replaced with a new\nallocated tags, see blk_mq_tag_update_depth().\n\nThe problem is that hctx-\u003esched_tags is from elevator-\u003eet-\u003etags, while\net-\u003etags is still the freed tags, hence later elevator exit will try to\nfree the tags again, causing kernel panic.\n\nFix this problem by replacing et-\u003etags with new allocated tags as well.\n\nNoted there are still some long term problems that will require some\nrefactor to be fixed thoroughly[1].\n\n[1] https://lore.kernel.org/all/20250815080216.410665-1-yukuai1@huaweicloud.com/"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T16:01:13.466Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/8faee580d63bc2a54a59dcdb7f9ce4de29384fec"
        },
        {
          "url": "https://git.kernel.org/stable/c/392b1d64911f4de8887fe8b68299fa8bd6e5b923"
        },
        {
          "url": "https://git.kernel.org/stable/c/ba28afbd9eff2a6370f23ef4e6a036ab0cfda409"
        }
      ],
      "title": "blk-mq: fix blk_mq_tags double free while nr_requests grown",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-39999",
    "datePublished": "2025-10-15T07:58:23.038Z",
    "dateReserved": "2025-04-16T07:20:57.151Z",
    "dateUpdated": "2026-05-23T16:01:13.466Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-39999",
      "date": "2026-10-22",
      "epss": "0.00197",
      "percentile": "0.08887"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "block/blk-mq-tag.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "8faee580d63bc2a54a59dcdb7f9ce4de29384fec",
                    "status": "affected",
                    "version": "58567d8e95c096ad234963df90a2ca518901f4b6",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "392b1d64911f4de8887fe8b68299fa8bd6e5b923",
                    "status": "affected",
                    "version": "f5a6604f7a4405450e4a1f54e5430f47290c500f",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "ba28afbd9eff2a6370f23ef4e6a036ab0cfda409",
                    "status": "affected",
                    "version": "f5a6604f7a4405450e4a1f54e5430f47290c500f",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "6.16.11",
                    "status": "affected",
                    "version": "6.16.4",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "block/blk-mq-tag.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.17"
                  },
                  {
                    "lessThan": "6.17",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.16.*",
                    "status": "unaffected",
                    "version": "6.16.11",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.17.*",
                    "status": "unaffected",
                    "version": "6.17.1",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.18",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblk-mq: fix blk_mq_tags double free while nr_requests grown\n\nIn the case user trigger tags grow by queue sysfs attribute nr_requests,\nhctx-\u003esched_tags will be freed directly and replaced with a new\nallocated tags, see blk_mq_tag_update_depth().\n\nThe problem is that hctx-\u003esched_tags is from elevator-\u003eet-\u003etags, while\net-\u003etags is still the freed tags, hence later elevator exit will try to\nfree the tags again, causing kernel panic.\n\nFix this problem by replacing et-\u003etags with new allocated tags as well.\n\nNoted there are still some long term problems that will require some\nrefactor to be fixed thoroughly[1].\n\n[1] https://lore.kernel.org/all/20250815080216.410665-1-yukuai1@huaweicloud.com/"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nblk-mq: correcci\u00f3n de la doble liberaci\u00f3n de blk_mq_tags mientras nr_requests crec\u00eda\n\nEn el caso de que el usuario active el crecimiento de las etiquetas mediante el atributo sysfs de la cola nr_requests, hctx-\u003esched_tags se liberar\u00e1 directamente y se reemplazar\u00e1 con nuevas etiquetas asignadas, v\u00e9ase blk_mq_tag_update_depth().\n\nEl problema es que hctx-\u003esched_tags proviene de elevator-\u003eet-\u003etags, mientras que et-\u003etags sigue siendo las etiquetas liberadas, por lo tanto, una salida posterior del elevador intentar\u00e1 liberar las etiquetas de nuevo, causando un p\u00e1nico del kernel.\n\nSoluciona este problema reemplazando et-\u003etags tambi\u00e9n con nuevas etiquetas asignadas.\n\nSe ha observado que todav\u00eda existen algunos problemas a largo plazo que requerir\u00e1n una refactorizaci\u00f3n para ser solucionados completamente[1].\n\n[1] https://lore.kernel.org/all/20250815080216.410665-1-yukuai1@huaweicloud.com/"
          }
        ],
        "id": "CVE-2025-39999",
        "lastModified": "2026-10-19T21:10:00.160",
        "metrics": {},
        "published": "2025-10-15T08:15:38.210",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/392b1d64911f4de8887fe8b68299fa8bd6e5b923"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/8faee580d63bc2a54a59dcdb7f9ce4de29384fec"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/ba28afbd9eff2a6370f23ef4e6a036ab0cfda409"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Deferred"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-06-30T01:28:44+00:00",
      "cve": "CVE-2025-39999",
      "id": "CVE-2025-39999",
      "initial_release_date": "2025-10-15T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: blk-mq: fix blk_mq_tags double free while nr_requests grown",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-39999.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.