github - ghsa-rv3q-w2vv-wgf5

GHSA-RV3Q-W2VV-WGF5

Vulnerability from github – Published: 2025-10-07 18:31 – Updated: 2025-10-07 18:31

Details

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

blk-iolatency: Fix memory leak on add_disk() failures

When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter.

This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called.

It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's.

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{
  "affected": [],
  "aliases": [
    "CVE-2022-50550"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-10-07T16:15:40Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nblk-iolatency: Fix memory leak on add_disk() failures\n\nWhen a gendisk is successfully initialized but add_disk() fails such as when\na loop device has invalid number of minor device numbers specified,\nblkcg_init_disk() is called during init and then blkcg_exit_disk() during\nerror handling. Unfortunately, iolatency gets initialized in the former but\ndoesn\u0027t get cleaned up in the latter.\n\nThis is because, in non-error cases, the cleanup is performed by\ndel_gendisk() calling rq_qos_exit(), the assumption being that rq_qos\npolicies, iolatency being one of them, can only be activated once the disk\nis fully registered and visible. That assumption is true for wbt and iocost,\nbut not so for iolatency as it gets initialized before add_disk() is called.\n\nIt is desirable to lazy-init rq_qos policies because they are optional\nfeatures and add to hot path overhead once initialized - each IO has to walk\nall the registered rq_qos policies. So, we want to switch iolatency to lazy\ninit too. However, that\u0027s a bigger change. As a fix for the immediate\nproblem, let\u0027s just add an extra call to rq_qos_exit() in blkcg_exit_disk().\nThis is safe because duplicate calls to rq_qos_exit() become noop\u0027s.",
  "id": "GHSA-rv3q-w2vv-wgf5",
  "modified": "2025-10-07T18:31:09Z",
  "published": "2025-10-07T18:31:09Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-50550"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/215f9437dda09531bcb80605298a24219f01cec5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2a126e1db5553ce4498290df019866952f858954"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/813e693023ba10da9e75067780f8378465bf27cc"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2022-50550 (GCVE-0-2022-50550)

Vulnerability from cvelistv5 – Published: 2025-10-07 15:21 – Updated: 2025-10-07 15:21

Summary

In the Linux kernel, the following vulnerability has been resolved: blk-iolatency: Fix memory leak on add_disk() failures When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter. This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called. It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/2a126e1db5553ce44…
	https://git.kernel.org/stable/c/215f9437dda09531b…
	https://git.kernel.org/stable/c/813e693023ba10da9…

Impacted products

Vendor

Product

Version

Linux

Affected: d70675121546c35feaceebf7ed9caed8716640f3 , < 2a126e1db5553ce4498290df019866952f858954 (git)
Affected: d70675121546c35feaceebf7ed9caed8716640f3 , < 215f9437dda09531bcb80605298a24219f01cec5 (git)
Affected: d70675121546c35feaceebf7ed9caed8716640f3 , < 813e693023ba10da9e75067780f8378465bf27cc (git)

Linux

Affected: 4.19
Unaffected: 0 , < 4.19 (semver)
Unaffected: 6.0.17 , ≤ 6.0.* (semver)
Unaffected: 6.1.2 , ≤ 6.1.* (semver)
Unaffected: 6.2 , ≤ * (original_commit_for_fix)

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JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "block/blk-cgroup.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2a126e1db5553ce4498290df019866952f858954",
              "status": "affected",
              "version": "d70675121546c35feaceebf7ed9caed8716640f3",
              "versionType": "git"
            },
            {
              "lessThan": "215f9437dda09531bcb80605298a24219f01cec5",
              "status": "affected",
              "version": "d70675121546c35feaceebf7ed9caed8716640f3",
              "versionType": "git"
            },
            {
              "lessThan": "813e693023ba10da9e75067780f8378465bf27cc",
              "status": "affected",
              "version": "d70675121546c35feaceebf7ed9caed8716640f3",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "block/blk-cgroup.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.19"
            },
            {
              "lessThan": "4.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.0.*",
              "status": "unaffected",
              "version": "6.0.17",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.0.17",
                  "versionStartIncluding": "4.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.2",
                  "versionStartIncluding": "4.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.2",
                  "versionStartIncluding": "4.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblk-iolatency: Fix memory leak on add_disk() failures\n\nWhen a gendisk is successfully initialized but add_disk() fails such as when\na loop device has invalid number of minor device numbers specified,\nblkcg_init_disk() is called during init and then blkcg_exit_disk() during\nerror handling. Unfortunately, iolatency gets initialized in the former but\ndoesn\u0027t get cleaned up in the latter.\n\nThis is because, in non-error cases, the cleanup is performed by\ndel_gendisk() calling rq_qos_exit(), the assumption being that rq_qos\npolicies, iolatency being one of them, can only be activated once the disk\nis fully registered and visible. That assumption is true for wbt and iocost,\nbut not so for iolatency as it gets initialized before add_disk() is called.\n\nIt is desirable to lazy-init rq_qos policies because they are optional\nfeatures and add to hot path overhead once initialized - each IO has to walk\nall the registered rq_qos policies. So, we want to switch iolatency to lazy\ninit too. However, that\u0027s a bigger change. As a fix for the immediate\nproblem, let\u0027s just add an extra call to rq_qos_exit() in blkcg_exit_disk().\nThis is safe because duplicate calls to rq_qos_exit() become noop\u0027s."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-10-07T15:21:12.689Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2a126e1db5553ce4498290df019866952f858954"
        },
        {
          "url": "https://git.kernel.org/stable/c/215f9437dda09531bcb80605298a24219f01cec5"
        },
        {
          "url": "https://git.kernel.org/stable/c/813e693023ba10da9e75067780f8378465bf27cc"
        }
      ],
      "title": "blk-iolatency: Fix memory leak on add_disk() failures",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2022-50550",
    "datePublished": "2025-10-07T15:21:12.689Z",
    "dateReserved": "2025-10-07T15:15:38.669Z",
    "dateUpdated": "2025-10-07T15:21:12.689Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

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-RV3Q-W2VV-WGF5

CVE-2022-50550 (GCVE-0-2022-50550)

Tags

Sightings

Nomenclature