dmaengine: pxa: fix double counting of the hw descriptors

{
  "id": "f438dabd31324de1814d1030158dec8ac6da2c8414c5c58a5dd1b4bc1ed348e9",
  "url": "https://osv.dev/vulnerability/CVE-2026-98324",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "dmaengine: pxa: fix double counting of the hw descriptors",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: dmaengine: pxa: fix double counting of the hw descriptors pxad_alloc_desc() was converted from kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc), GFP_NOWAIT) to kzalloc_flex(), which sets the __counted_by() counter sw_desc->nb_desc itself - but only where the compiler has __builtin_counted_by_ref(), so from gcc 15.1 or clang 22.1 on. The loop below it still increments nb_desc, which makes it come out doubled there and correct elsewhere. nb_desc is what pxad_free_desc() iterates over and what set_updater_desc() indexes from, so set it explicitly and drop the increment. The error path has to lower it to the number of descriptors allocated so far, otherwise pxad_free_desc() would free entries that were never allocated.",
    "evidence": "osv:CVE-2026-98324",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "7.2.8",
            "evidence": "/affected/1/ranges"
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        "affected_versions": []
      }
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    "severity": "high",
    "structured": {
      "id": "CVE-2026-98324",
      "aliases": [
        "CVE-2026-98324"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
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      "affected": [
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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                  "fixed": "f6504be006aa4bb4bd26285f410a885c17920d65"
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          "database_specific": {
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        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
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                  "introduced": "7.0.0"
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                {
                  "fixed": "7.2.8"
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98324.json"
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        }
      ],
      "modified": "2026-10-28T02:30:48.516037626Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1de93785f32b450e9eae1e4fcfb7d03eb49eb27e",
        "https://git.kernel.org/stable/c/f6504be006aa4bb4bd26285f410a885c17920d65",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98324.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-98324",
        "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/2026/98xxx/CVE-2026-98324.json"
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    "related_cves": [
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        "value": "CVE-2026-98324",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
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  "source_id": "core-osv",
  "document_id": 516744,
  "published_at": "2026-10-06T08:46:17.919+00:00"
}