CVE-2026-89805 (GCVE-0-2026-89805)

Vulnerability from cvelistv5 – Published: 2026-09-16 10:30 – Updated: 2026-10-19 08:52
VLAI
Title
drm/pagemap: Fix folio allocation fallback and use-after-put
Summary
In the Linux kernel, the following vulnerability has been resolved: drm/pagemap: Fix folio allocation fallback and use-after-put drm_pagemap_migrate_populate_ram_pfn() had two issues when populating RAM PFNs with higher-order folios: 1. The higher-order vma_alloc_folio()/folio_alloc() calls did not pass __GFP_NOWARN, so a THP allocation failure under memory pressure would spam the kernel log, and there was no fallback path despite a TODO comment stating one was needed. Add __GFP_NOWARN to the higher-order allocation and, on failure, fall back to order-0 allocations for the entire range originally covered by the failed higher-order allocation, leaving MIGRATE_PFN_COMPOUND unset for those PFNs. 2. In the free_pages error path, order was computed via folio_order(page_folio(page)) *after* put_page(page) had already dropped the reference, resulting in a use-after-free/put when that was the last reference on the page. Compute order before releasing the page. Introducing the fallback in 1. also requires the source page array handed to ->copy_to_ram() to be built differently. Both callers only populated the entry at the head of each source folio, relying on the copy callback to derive the rest of the folio from the order recorded in the matching drm_pagemap_addr. Once the destination has been demoted to order-0 folios the drm_pagemap_addr entries are per-page, so a source page is needed for every one of them; leaving them NULL makes the copy callback stop after the first page and the remainder of the range is never copied. The source folio is only split later, by migrate_vma_pages() / migrate_device_pages(), so its order cannot be used to detect the demotion - test the destination for MIGRATE_PFN_COMPOUND instead. Factor the array population out into drm_pagemap_migrate_populate_src_pages() and use it from both drm_pagemap_evict_to_ram() and __drm_pagemap_migrate_to_ram().
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6639 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ddeda6136038b4b313bb6f9b44f2d363e1233814 , < 10e92e18e3dab081789d868878f2ecce6166948a (git)
Affected: ddeda6136038b4b313bb6f9b44f2d363e1233814 , < df72e55e754c8d449321ddddad19a8bd3cb8d032 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.18
Unaffected: 0 , < 6.18 (semver)
Unaffected: 7.2.5 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/drm_pagemap.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "10e92e18e3dab081789d868878f2ecce6166948a",
              "status": "affected",
              "version": "ddeda6136038b4b313bb6f9b44f2d363e1233814",
              "versionType": "git"
            },
            {
              "lessThan": "df72e55e754c8d449321ddddad19a8bd3cb8d032",
              "status": "affected",
              "version": "ddeda6136038b4b313bb6f9b44f2d363e1233814",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/drm_pagemap.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.18"
            },
            {
              "lessThan": "6.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.5",
              "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": "7.2.5",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/pagemap: Fix folio allocation fallback and use-after-put\n\ndrm_pagemap_migrate_populate_ram_pfn() had two issues when populating\nRAM PFNs with higher-order folios:\n\n1. The higher-order vma_alloc_folio()/folio_alloc() calls did not pass\n   __GFP_NOWARN, so a THP allocation failure under memory pressure\n   would spam the kernel log, and there was no fallback path despite a\n   TODO comment stating one was needed. Add __GFP_NOWARN to the\n   higher-order allocation and, on failure, fall back to order-0\n   allocations for the entire range originally covered by the failed\n   higher-order allocation, leaving MIGRATE_PFN_COMPOUND unset for\n   those PFNs.\n\n2. In the free_pages error path, order was computed via\n   folio_order(page_folio(page)) *after* put_page(page) had already\n   dropped the reference, resulting in a use-after-free/put when that\n   was the last reference on the page. Compute order before releasing\n   the page.\n\nIntroducing the fallback in 1. also requires the source page array\nhanded to -\u003ecopy_to_ram() to be built differently. Both callers only\npopulated the entry at the head of each source folio, relying on the\ncopy callback to derive the rest of the folio from the order recorded\nin the matching drm_pagemap_addr. Once the destination has been demoted\nto order-0 folios the drm_pagemap_addr entries are per-page, so a source\npage is needed for every one of them; leaving them NULL makes the copy\ncallback stop after the first page and the remainder of the range is\nnever copied.\n\nThe source folio is only split later, by migrate_vma_pages() /\nmigrate_device_pages(), so its order cannot be used to detect the\ndemotion - test the destination for MIGRATE_PFN_COMPOUND instead. Factor\nthe array population out into drm_pagemap_migrate_populate_src_pages()\nand use it from both drm_pagemap_evict_to_ram() and\n__drm_pagemap_migrate_to_ram()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The UAF is in drm_pagemap_migrate_populate_ram_pfn on the migrate-to-RAM path, reached from a local CPU fault on device-private SVM pages (do_swap_page \u2192 drm_pagemap_migrate_to_ram) or Xe TTM eviction (xe_svm_bo_evict \u2192 drm_pagemap_evict_to_ram), not from network packets.\nAC:L - The attacker controls SVM setup and can force the free_pages path by failing a later GFP_HIGHUSER/THP allocation under self-induced memory pressure or fragmentation after earlier folios succeeded; the use-after-put then runs deterministically with no victim timing.\nPR:L - DRM_IOCTL_XE_VM_CREATE and VM_BIND are DRM_RENDER_ALLOW with no capable() or DRM-master check. An unprivileged user with typical render/video-group access to /dev/dri/renderD* on an Intel Xe discrete GPU can create a fault-mode SVM VM and trigger migration.\nUI:N - The attacking process drives mmap, SVM bind/prefetch to VRAM, migrate-back via CPU access or VRAM eviction, and memory pressure itself; no separate victim action is required.\nS:U - The UAF corrupts host kernel page-allocator metadata in the same security authority. This is standard local kernel privilege escalation, not a KVM/Xen guest-to-host escape or IOMMU/DMA boundary bypass.\nC:H - put_page() drops the last reference on the just-allocated folio, then folio_order(page_folio(page)) reads the freed page struct and may follow stale compound_info tail encoding, yielding an arbitrary kernel read of vmemmap/page flags.\nI:H - The same use-after-put lets reused or stale page flags supply an attacker-influenced order that skips remaining puts or corrupts the free loop, and a page-struct UAF is exploitable via buddy reuse for arbitrary kernel writes or control-flow hijack.\nA:H - Accessing a freed or reused page struct can oops or panic, and a corrupted order that makes NR_PAGES() return 0 hangs in an infinite free_pages loop; any kernel UAF is high availability impact."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T08:52:59.787Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/10e92e18e3dab081789d868878f2ecce6166948a"
        },
        {
          "url": "https://git.kernel.org/stable/c/df72e55e754c8d449321ddddad19a8bd3cb8d032"
        }
      ],
      "title": "drm/pagemap: Fix folio allocation fallback and use-after-put",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89805",
    "datePublished": "2026-09-16T10:30:38.606Z",
    "dateReserved": "2026-09-11T19:38:34.767Z",
    "dateUpdated": "2026-10-19T08:52:59.787Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-89805",
      "date": "2026-11-10",
      "epss": "0.00165",
      "percentile": "0.05772"
    },
    "microsoft_vex": {
      "current_release_date": "2026-10-22T01:11:26.000Z",
      "cve": "CVE-2026-89805",
      "id": "msrc_CVE-2026-89805",
      "initial_release_date": "2026-10-22T01:11:26.000Z",
      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "drm/pagemap: Fix folio allocation fallback and use-after-put",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-89805.json",
      "version": "1"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "drivers/gpu/drm/drm_pagemap.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "10e92e18e3dab081789d868878f2ecce6166948a",
                    "status": "affected",
                    "version": "ddeda6136038b4b313bb6f9b44f2d363e1233814",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "df72e55e754c8d449321ddddad19a8bd3cb8d032",
                    "status": "affected",
                    "version": "ddeda6136038b4b313bb6f9b44f2d363e1233814",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "drivers/gpu/drm/drm_pagemap.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.18"
                  },
                  {
                    "lessThan": "6.18",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.5",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/pagemap: Fix folio allocation fallback and use-after-put\n\ndrm_pagemap_migrate_populate_ram_pfn() had two issues when populating\nRAM PFNs with higher-order folios:\n\n1. The higher-order vma_alloc_folio()/folio_alloc() calls did not pass\n   __GFP_NOWARN, so a THP allocation failure under memory pressure\n   would spam the kernel log, and there was no fallback path despite a\n   TODO comment stating one was needed. Add __GFP_NOWARN to the\n   higher-order allocation and, on failure, fall back to order-0\n   allocations for the entire range originally covered by the failed\n   higher-order allocation, leaving MIGRATE_PFN_COMPOUND unset for\n   those PFNs.\n\n2. In the free_pages error path, order was computed via\n   folio_order(page_folio(page)) *after* put_page(page) had already\n   dropped the reference, resulting in a use-after-free/put when that\n   was the last reference on the page. Compute order before releasing\n   the page.\n\nIntroducing the fallback in 1. also requires the source page array\nhanded to -\u003ecopy_to_ram() to be built differently. Both callers only\npopulated the entry at the head of each source folio, relying on the\ncopy callback to derive the rest of the folio from the order recorded\nin the matching drm_pagemap_addr. Once the destination has been demoted\nto order-0 folios the drm_pagemap_addr entries are per-page, so a source\npage is needed for every one of them; leaving them NULL makes the copy\ncallback stop after the first page and the remainder of the range is\nnever copied.\n\nThe source folio is only split later, by migrate_vma_pages() /\nmigrate_device_pages(), so its order cannot be used to detect the\ndemotion - test the destination for MIGRATE_PFN_COMPOUND instead. Factor\nthe array population out into drm_pagemap_migrate_populate_src_pages()\nand use it from both drm_pagemap_evict_to_ram() and\n__drm_pagemap_migrate_to_ram()."
          }
        ],
        "id": "CVE-2026-89805",
        "lastModified": "2026-10-19T09:18:24.307",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-09-16T11:16:45.470",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/10e92e18e3dab081789d868878f2ecce6166948a"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/df72e55e754c8d449321ddddad19a8bd3cb8d032"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-11-06T01:24:00+00:00",
      "cve": "CVE-2026-89805",
      "id": "CVE-2026-89805",
      "initial_release_date": "2026-09-16T00:00:00+00:00",
      "product_status:known_affected": "110",
      "product_status:known_not_affected": "93",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: drm/pagemap: Fix folio allocation fallback and use-after-put",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89805.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.