Vulnerability-Lookup

GHSA-JP52-G472-3CPX

Vulnerability from github – Published: 2026-04-24 15:32 – Updated: 2026-04-24 15:32

Details

In the Linux kernel, the following vulnerability has been resolved:

mm/damon/stat: deallocate damon_call() failure leaking damon_ctx

damon_stat_start() always allocates the module's damon_ctx object (damon_stat_context). Meanwhile, if damon_call() in the function fails, the damon_ctx object is not deallocated. Hence, if the damon_call() is failed, and the user writes Y to “enabled” again, the previously allocated damon_ctx object is leaked.

This cannot simply be fixed by deallocating the damon_ctx object when damon_call() fails. That's because damon_call() failure doesn't guarantee the kdamond main function, which accesses the damon_ctx object, is completely finished. In other words, if damon_stat_start() deallocates the damon_ctx object after damon_call() failure, the not-yet-terminated kdamond could access the freed memory (use-after-free).

Fix the leak while avoiding the use-after-free by keeping returning damon_stat_start() without deallocating the damon_ctx object after damon_call() failure, but deallocating it when the function is invoked again and the kdamond is completely terminated. If the kdamond is not yet terminated, simply return -EAGAIN, as the kdamond will soon be terminated.

The issue was discovered [1] by sashiko.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-31652"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-24T15:16:44Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/stat: deallocate damon_call() failure leaking damon_ctx\n\ndamon_stat_start() always allocates the module\u0027s damon_ctx object\n(damon_stat_context).  Meanwhile, if damon_call() in the function fails,\nthe damon_ctx object is not deallocated.  Hence, if the damon_call() is\nfailed, and the user writes Y to \u201cenabled\u201d again, the previously\nallocated damon_ctx object is leaked.\n\nThis cannot simply be fixed by deallocating the damon_ctx object when\ndamon_call() fails.  That\u0027s because damon_call() failure doesn\u0027t guarantee\nthe kdamond main function, which accesses the damon_ctx object, is\ncompletely finished.  In other words, if damon_stat_start() deallocates\nthe damon_ctx object after damon_call() failure, the not-yet-terminated\nkdamond could access the freed memory (use-after-free).\n\nFix the leak while avoiding the use-after-free by keeping returning\ndamon_stat_start() without deallocating the damon_ctx object after\ndamon_call() failure, but deallocating it when the function is invoked\nagain and the kdamond is completely terminated.  If the kdamond is not yet\nterminated, simply return -EAGAIN, as the kdamond will soon be terminated.\n\nThe issue was discovered [1] by sashiko.",
  "id": "GHSA-jp52-g472-3cpx",
  "modified": "2026-04-24T15:32:36Z",
  "published": "2026-04-24T15:32:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31652"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/16c92e9bf55fa049ddb5e894dc0623dacd46a620"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/447f8870b484f6596d7a7130e72bd0a3f1e037bb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4c04c6b47c361612b1d70cec8f7a60b1482d1400"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-31652 (GCVE-0-2026-31652)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:45 – Updated: 2026-04-24 14:45

Title

mm/damon/stat: deallocate damon_call() failure leaking damon_ctx

Summary

In the Linux kernel, the following vulnerability has been resolved: mm/damon/stat: deallocate damon_call() failure leaking damon_ctx damon_stat_start() always allocates the module's damon_ctx object (damon_stat_context). Meanwhile, if damon_call() in the function fails, the damon_ctx object is not deallocated. Hence, if the damon_call() is failed, and the user writes Y to “enabled” again, the previously allocated damon_ctx object is leaked. This cannot simply be fixed by deallocating the damon_ctx object when damon_call() fails. That's because damon_call() failure doesn't guarantee the kdamond main function, which accesses the damon_ctx object, is completely finished. In other words, if damon_stat_start() deallocates the damon_ctx object after damon_call() failure, the not-yet-terminated kdamond could access the freed memory (use-after-free). Fix the leak while avoiding the use-after-free by keeping returning damon_stat_start() without deallocating the damon_ctx object after damon_call() failure, but deallocating it when the function is invoked again and the kdamond is completely terminated. If the kdamond is not yet terminated, simply return -EAGAIN, as the kdamond will soon be terminated. The issue was discovered [1] by sashiko.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/447f8870b484f6596…
	https://git.kernel.org/stable/c/16c92e9bf55fa049d…
	https://git.kernel.org/stable/c/4c04c6b47c361612b…

Impacted products

Vendor

Product

Version

Linux

Affected: 405f61996d9d2e9d497cd9f6b66f41dc28d3d1d8 , < 447f8870b484f6596d7a7130e72bd0a3f1e037bb (git)
Affected: 405f61996d9d2e9d497cd9f6b66f41dc28d3d1d8 , < 16c92e9bf55fa049ddb5e894dc0623dacd46a620 (git)
Affected: 405f61996d9d2e9d497cd9f6b66f41dc28d3d1d8 , < 4c04c6b47c361612b1d70cec8f7a60b1482d1400 (git)

Linux

Affected: 6.17
Unaffected: 0 , < 6.17 (semver)
Unaffected: 6.18.23 , ≤ 6.18.* (semver)
Unaffected: 6.19.13 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "mm/damon/stat.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "447f8870b484f6596d7a7130e72bd0a3f1e037bb",
              "status": "affected",
              "version": "405f61996d9d2e9d497cd9f6b66f41dc28d3d1d8",
              "versionType": "git"
            },
            {
              "lessThan": "16c92e9bf55fa049ddb5e894dc0623dacd46a620",
              "status": "affected",
              "version": "405f61996d9d2e9d497cd9f6b66f41dc28d3d1d8",
              "versionType": "git"
            },
            {
              "lessThan": "4c04c6b47c361612b1d70cec8f7a60b1482d1400",
              "status": "affected",
              "version": "405f61996d9d2e9d497cd9f6b66f41dc28d3d1d8",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "mm/damon/stat.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": "6.18.*",
              "status": "unaffected",
              "version": "6.18.23",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.23",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.13",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/stat: deallocate damon_call() failure leaking damon_ctx\n\ndamon_stat_start() always allocates the module\u0027s damon_ctx object\n(damon_stat_context).  Meanwhile, if damon_call() in the function fails,\nthe damon_ctx object is not deallocated.  Hence, if the damon_call() is\nfailed, and the user writes Y to \u201cenabled\u201d again, the previously\nallocated damon_ctx object is leaked.\n\nThis cannot simply be fixed by deallocating the damon_ctx object when\ndamon_call() fails.  That\u0027s because damon_call() failure doesn\u0027t guarantee\nthe kdamond main function, which accesses the damon_ctx object, is\ncompletely finished.  In other words, if damon_stat_start() deallocates\nthe damon_ctx object after damon_call() failure, the not-yet-terminated\nkdamond could access the freed memory (use-after-free).\n\nFix the leak while avoiding the use-after-free by keeping returning\ndamon_stat_start() without deallocating the damon_ctx object after\ndamon_call() failure, but deallocating it when the function is invoked\nagain and the kdamond is completely terminated.  If the kdamond is not yet\nterminated, simply return -EAGAIN, as the kdamond will soon be terminated.\n\nThe issue was discovered [1] by sashiko."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-24T14:45:04.930Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/447f8870b484f6596d7a7130e72bd0a3f1e037bb"
        },
        {
          "url": "https://git.kernel.org/stable/c/16c92e9bf55fa049ddb5e894dc0623dacd46a620"
        },
        {
          "url": "https://git.kernel.org/stable/c/4c04c6b47c361612b1d70cec8f7a60b1482d1400"
        }
      ],
      "title": "mm/damon/stat: deallocate damon_call() failure leaking damon_ctx",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31652",
    "datePublished": "2026-04-24T14:45:04.930Z",
    "dateReserved": "2026-03-09T15:48:24.128Z",
    "dateUpdated": "2026-04-24T14:45:04.930Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-JP52-G472-3CPX

CVE-2026-31652 (GCVE-0-2026-31652)

Tags

Sightings

Nomenclature