CVE-2026-64293 iommufd: Use sizeof(*hdr) instead of sizeof(hdr) in veventq read

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/iommu/iommufd/eventq.c"
    ],
    "versions": [
      {
        "version": "e36ba5ab808ef6237c3148d469c8238674230e2b",
        "lessThan": "04a177f91160ee18da98f5689482cf0f589ec869",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "e36ba5ab808ef6237c3148d469c8238674230e2b",
        "lessThan": "0cdbb97a4dbd69abdd2ab998b4fbc7803d4b0b72",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "e36ba5ab808ef6237c3148d469c8238674230e2b",
        "lessThan": "be93d186ae88a92e7aa77e122d4e661fa57b1e39",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/iommu/iommufd/eventq.c"
    ],
    "versions": [
      {
        "version": "6.15",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "6.15",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "6.18.39",
        "lessThanOrEqual": "6.18.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "7.1.4",
        "lessThanOrEqual": "7.1.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "7.2-rc1",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]