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CVE-2026-89856

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation ha->msix_count is u16, but ha->max_req_queues, ha->max_rsp_queues and ha->max_qpairs are u8. Deriving the queue count as "ha->max_req_queues = ha->msix_count - 1" therefore truncates: a board (or a misconfigured/malicious hot-plugged device) advertising 257 MSI-X vectors yields msix_count - 1 == 256, which truncates to 0. An MSI-X count of 1 zeroes it as well, and in target mode the subsequent "ha->max_req_queues--" then underflows 0 to 255. When the count is 0, qla2x00_alloc_queues() calls kzalloc_objs(struct req_que *, 0), which returns ZERO_SIZE_PTR. That is not NULL, so the allocation check passes and the following "ha->req_q_map[0] = req" dereferences ZERO_SIZE_PTR, corrupting memory or crashing the kernel. Add qla_calc_queue_count() to clamp the derived value into [1, QLA_MAX_QUEUES - 1] so it always fits in u8 and is never zero, and use it at all three derivation sites (qla25xx_iospace_config(), qla83xx_iospace_config() and qla24xx_enable_msix()). Also guard the target-mode decrement so it cannot reintroduce a zero (which would in turn underflow max_qpairs).

Severity
HIGH
CVSS score
8.4 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 11:16:53.440000
Last modified
2026-10-19 09:18:29.960000
View original CVE JSON
{
  "id": "CVE-2026-89856",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:16:53.440",
  "lastModified": "2026-10-19T09:18:29.960",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation\n\nha->msix_count is u16, but ha->max_req_queues, ha->max_rsp_queues and\nha->max_qpairs are u8. Deriving the queue count as\n\"ha->max_req_queues = ha->msix_count - 1\" therefore truncates: a board\n(or a misconfigured/malicious hot-plugged device) advertising 257 MSI-X\nvectors yields msix_count - 1 == 256, which truncates to 0. An MSI-X\ncount of 1 zeroes it as well, and in target mode the subsequent\n\"ha->max_req_queues--\" then underflows 0 to 255.\n\nWhen the count is 0, qla2x00_alloc_queues() calls\nkzalloc_objs(struct req_que *, 0), which returns ZERO_SIZE_PTR. That is\nnot NULL, so the allocation check passes and the following\n\"ha->req_q_map[0] = req\" dereferences ZERO_SIZE_PTR, corrupting memory\nor crashing the kernel.\n\nAdd qla_calc_queue_count() to clamp the derived value into\n[1, QLA_MAX_QUEUES - 1] so it always fits in u8 and is never zero, and\nuse it at all three derivation sites (qla25xx_iospace_config(),\nqla83xx_iospace_config() and qla24xx_enable_msix()). Also guard the\ntarget-mode decrement so it cannot reintroduce a zero (which would in\nturn underflow max_qpairs)."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/scsi/qla2xxx/qla_inline.h",
            "drivers/scsi/qla2xxx/qla_isr.c",
            "drivers/scsi/qla2xxx/qla_os.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "cf623d32761b00f221a9cfded3303d56e84b429d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "9eeddbeaa896f39d943644b16d83a6ad0ceab255",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "802068b9b683b8008fcccbf6e9ad133e597ec87c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "e80adfeac61b4d5db7ffe0f5af43999c33a4145e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "2efe50b2da829909023de4a2eb87badb7cfa53cc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "7a448f5ed0b283dbde4e9183dd1e98c221432dab",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "33c77254e6e91f37c72c7fad4051777452b10de8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d74595278f4ab192af66d9e60a9087464638beee",
              "lessThan": "ebfd35c64433821bd5619a6d07ccc2df8b5b1de3",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/scsi/qla2xxx/qla_inline.h",
            "drivers/scsi/qla2xxx/qla_isr.c",
            "drivers/scsi/qla2xxx/qla_os.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4.10",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "4.10",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "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:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/2efe50b2da829909023de4a2eb87badb7cfa53cc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/33c77254e6e91f37c72c7fad4051777452b10de8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7a448f5ed0b283dbde4e9183dd1e98c221432dab",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/802068b9b683b8008fcccbf6e9ad133e597ec87c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9eeddbeaa896f39d943644b16d83a6ad0ceab255",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cf623d32761b00f221a9cfded3303d56e84b429d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e80adfeac61b4d5db7ffe0f5af43999c33a4145e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ebfd35c64433821bd5619a6d07ccc2df8b5b1de3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}