HighFix available

scsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation

Type: advisorySources: OSV

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).

Products: Kernel
Affected versions: Not specified
Fixed versions: 5.10.270, 5.15.221, 6.1.188, 6.12.110, 6.18.51, 6.6.157, 7.2.5
CVEs: CVE-2026-89856
Confirmed fixed CVEs: Not specified
Updated in this feed: 7 Nov 2026, 01:56 UTC · Revision 1

Source evidence

scsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation

core-osv · Original source

Published 16 Sept 2026, 10:31 UTC

osv:CVE-2026-89856

Kernel

Fixed versions: 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.5

Complete source record

{
  "id": "adf8b4145ab63418ba65b3f6fe533cd6e46a6269a295df2d59083ebfc27527d0",
  "url": "https://osv.dev/vulnerability/CVE-2026-89856",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "scsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation",
    "summary": "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).",
    "evidence": "osv:CVE-2026-89856",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
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        "prerequisites": [],
        "fixed_versions": [
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            "evidence": "/affected/1/ranges"
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            "evidence": "/affected/1/ranges"
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            "evidence": "/affected/1/ranges"
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          {
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            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.110",
            "evidence": "/affected/1/ranges"
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          {
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            "evidence": "/affected/1/ranges"
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          {
            "value": "7.2.5",
            "evidence": "/affected/1/ranges"
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        "affected_versions": []
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    "severity": "high",
    "structured": {
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      "aliases": [
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      "metrics": [
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          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
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      "affected": [
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        },
        {
          "ranges": [
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              "type": "ECOSYSTEM",
              "events": [
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                  "introduced": "4.10.0"
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            {
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      "modified": "2026-10-28T02:30:48.786157968Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2efe50b2da829909023de4a2eb87badb7cfa53cc",
        "https://git.kernel.org/stable/c/33c77254e6e91f37c72c7fad4051777452b10de8",
        "https://git.kernel.org/stable/c/7a448f5ed0b283dbde4e9183dd1e98c221432dab",
        "https://git.kernel.org/stable/c/802068b9b683b8008fcccbf6e9ad133e597ec87c",
        "https://git.kernel.org/stable/c/9eeddbeaa896f39d943644b16d83a6ad0ceab255",
        "https://git.kernel.org/stable/c/cf623d32761b00f221a9cfded3303d56e84b429d",
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        "https://git.kernel.org/stable/c/ebfd35c64433821bd5619a6d07ccc2df8b5b1de3",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89856.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-89856",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89856.json"
      }
    },
    "related_cves": [
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        "value": "CVE-2026-89856",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 517157,
  "published_at": "2026-09-16T10:31:29.517+00:00"
}