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CVE-2026-89503

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Fix subbuf resize race with ring_buffer_alloc_read_page() ring_buffer_alloc_read_page() is racy with ring_buffer_subbuf_order_set, it can allocate a reader page with an outdated order. This isn't a big issue, the user can still re-allocate a new reader page and try again. However, what is more problematic is if the value of subbuf_order changes in the middle of ring_buffer_alloc_read_page(). In that case, bpage->order might not match the actual allocated memory. Use bpage->order for the allocation to prevent this race.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-11 20:19:32.547000
Last modified
2026-10-19 09:17:44.507000
View original CVE JSON
{
  "id": "CVE-2026-89503",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:32.547",
  "lastModified": "2026-10-19T09:17:44.507",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix subbuf resize race with ring_buffer_alloc_read_page()\n\nring_buffer_alloc_read_page() is racy with ring_buffer_subbuf_order_set,\nit can allocate a reader page with an outdated order. This isn't a big\nissue, the user can still re-allocate a new reader page and try again.\n\nHowever, what is more problematic is if the value of subbuf_order\nchanges in the middle of ring_buffer_alloc_read_page(). In that case,\nbpage->order might not match the actual allocated memory.\n\nUse bpage->order for the allocation to prevent this race."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/trace/ring_buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "bce761d757452ba5eb77e11fecc37a04b67494e7",
              "lessThan": "2313ff69bd237aad264a5913907f374f958335a2",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "bce761d757452ba5eb77e11fecc37a04b67494e7",
              "lessThan": "2dc510957fe8fd098ab3c3147ebdf34d00cd2734",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "bce761d757452ba5eb77e11fecc37a04b67494e7",
              "lessThan": "53106e9262a310ef2c9a9321168c03705940c678",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "bce761d757452ba5eb77e11fecc37a04b67494e7",
              "lessThan": "e743527c5bfdceda1095bc0a9e596e2aebb6a9c3",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/trace/ring_buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.8",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.8",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.112",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "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/2313ff69bd237aad264a5913907f374f958335a2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2dc510957fe8fd098ab3c3147ebdf34d00cd2734",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/53106e9262a310ef2c9a9321168c03705940c678",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e743527c5bfdceda1095bc0a9e596e2aebb6a9c3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}