CVE-2026-98282 (GCVE-0-2026-98282)
Vulnerability from cvelistv5
Published
2026-10-06 08:45
Modified
2026-10-19 09:16
Severity ?
8.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: powerpc/iommu: Fix the overflow validation in iommu_tce_check_ioba The commit b1af23d836f8 ("KVM: PPC: iommu: Unify TCE checking") unified IOBA parameter checking across KVM and VFIO into iommu_tce_check_ioba(). While doing so, the passed in argument npages is ignored and constant value '1' is used leaving out a possible overflow as the callers can legitimately be using npages > 1 for H_STUFF_TCE or H_PUT_TCE_INDIRECT cases. Fix this by accounting for 'npages', checking for arithmetic overflow, and verifying that the entire requested range (ioba - offset + npages) does not exceed the table capacity 'size'.
References
Impacted products
Vendor Product Version
Linux Linux Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
Version: b1af23d836f811137d504d14d4cbdd01929dec34
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/kernel/iommu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "98d8dcc4ebd10523507d4478e148809a7771a213",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "9fd9c9bbb05417f468a11fb6d145d7ff61f4a868",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "3776bf56e06980e8a12c8c0565d9e6ac44965f03",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "d6a1779129d936bc1fbab80181165da544eab736",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "d48ceb6e1a6915c7bac4f902554a1047365cdff2",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "0543813753ef5cfbd6fa96694f7acf783fa01af7",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "314091243159f8e3749bc719bb129f423f72fd86",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            },
            {
              "lessThan": "0b271f7d7f5ed45bc498a03ce0aa9cfd8402fc71",
              "status": "affected",
              "version": "b1af23d836f811137d504d14d4cbdd01929dec34",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/kernel/iommu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.12"
            },
            {
              "lessThan": "4.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.271",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.222",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.189",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.158",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.112",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.54",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.271",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.222",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.189",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.158",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.112",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.54",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.8",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/iommu: Fix the overflow validation in iommu_tce_check_ioba\n\nThe commit b1af23d836f8 (\"KVM: PPC: iommu: Unify TCE checking\") unified\nIOBA parameter checking across KVM and VFIO into iommu_tce_check_ioba().\nWhile doing so, the passed in argument npages is ignored and constant\nvalue \u00271\u0027 is used leaving out a possible overflow as the callers can\nlegitimately be using npages \u003e 1 for H_STUFF_TCE or H_PUT_TCE_INDIRECT\ncases.\n\nFix this by accounting for \u0027npages\u0027, checking for arithmetic overflow,\nand verifying that the entire requested range (ioba - offset + npages)\ndoes not exceed the table capacity \u0027size\u0027."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bad ioba/npages values come from a KVM guest\u0027s H_STUFF_TCE or H_PUT_TCE_INDIRECT hypercall registers. book3s_hv.c passes them to kvmppc_h_stuff_tce()/kvmppc_h_put_tce_indirect(), which call kvmppc_ioba_validate() -\u003e iommu_tce_check_ioba(). The attacker is code running on the host in a guest, not a remote network peer.\nAC:L - The guest picks liobn, ioba (the last valid entry) and npages itself. The flawed check only tests ioba+1, so every such hypercall reliably walks kvmppc_tce_put() past stt-\u003esize. No race or outside condition is involved; only heap grooming affects how far exploitation goes.\nPR:L - The attacker needs kernel privilege inside their own guest, which any tenant of a pseries KVM VM has. Relative to the host, that is a low-privilege tenant position. The guest\u0027s TCE table already exists because QEMU creates it through KVM_CREATE_SPAPR_TCE_64 for the default PHB/VIO DMA windows.\nUI:N - The guest issues the hypercalls whenever it wants. No action by the host administrator or any other user is needed.\nS:C - A guest-controlled hypercall corrupts host kernel memory and touches the host\u0027s hardware IOMMU table outside the guest\u0027s DMA window. The impact therefore crosses the guest-to-host virtualization boundary.\nC:H - kvmppc_tce_put() and kvmppc_h_get_tce paths index stt-\u003epages[] past the kmalloc\u0027d flexible array, and the TCE iommu_unmap/map paths use entries beyond the window. This gives out-of-bounds access to host heap and IOMMU state that can be turned into host memory disclosure.\nI:H - In H_STUFF_TCE, npages is unbounded and tce_value is guest-chosen. kvmppc_tce_put() writes that 8-byte value through an out-of-bounds stt-\u003epages[] pointer, or stores a newly allocated page pointer into the out-of-bounds slot. Both are host heap writes.\nA:H - Dereferencing an out-of-bounds stt-\u003epages[] entry as a struct page, or corrupting the host heap and IOMMU tables, crashes or oopses the host. That takes down every VM running on it."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T09:16:53.780Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/98d8dcc4ebd10523507d4478e148809a7771a213"
        },
        {
          "url": "https://git.kernel.org/stable/c/9fd9c9bbb05417f468a11fb6d145d7ff61f4a868"
        },
        {
          "url": "https://git.kernel.org/stable/c/3776bf56e06980e8a12c8c0565d9e6ac44965f03"
        },
        {
          "url": "https://git.kernel.org/stable/c/d6a1779129d936bc1fbab80181165da544eab736"
        },
        {
          "url": "https://git.kernel.org/stable/c/d48ceb6e1a6915c7bac4f902554a1047365cdff2"
        },
        {
          "url": "https://git.kernel.org/stable/c/0543813753ef5cfbd6fa96694f7acf783fa01af7"
        },
        {
          "url": "https://git.kernel.org/stable/c/314091243159f8e3749bc719bb129f423f72fd86"
        },
        {
          "url": "https://git.kernel.org/stable/c/0b271f7d7f5ed45bc498a03ce0aa9cfd8402fc71"
        }
      ],
      "title": "powerpc/iommu: Fix the overflow validation in iommu_tce_check_ioba",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98282",
    "datePublished": "2026-10-06T08:45:43.775Z",
    "dateReserved": "2026-09-25T10:25:14.335Z",
    "dateUpdated": "2026-10-19T09:16:53.780Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.