CVE-2025-40205 (GCVE-0-2025-40205)
Vulnerability from cvelistv5
Published
2025-11-12 21:56
Modified
2025-11-12 21:56
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: btrfs: avoid potential out-of-bounds in btrfs_encode_fh() The function btrfs_encode_fh() does not properly account for the three cases it handles. Before writing to the file handle (fh), the function only returns to the user BTRFS_FID_SIZE_NON_CONNECTABLE (5 dwords, 20 bytes) or BTRFS_FID_SIZE_CONNECTABLE (8 dwords, 32 bytes). However, when a parent exists and the root ID of the parent and the inode are different, the function writes BTRFS_FID_SIZE_CONNECTABLE_ROOT (10 dwords, 40 bytes). If *max_len is not large enough, this write goes out of bounds because BTRFS_FID_SIZE_CONNECTABLE_ROOT is greater than BTRFS_FID_SIZE_CONNECTABLE originally returned. This results in an 8-byte out-of-bounds write at fid->parent_root_objectid = parent_root_id. A previous attempt to fix this issue was made but was lost. https://lore.kernel.org/all/4CADAEEC020000780001B32C@vpn.id2.novell.com/ Although this issue does not seem to be easily triggerable, it is a potential memory corruption bug that should be fixed. This patch resolves the issue by ensuring the function returns the appropriate size for all three cases and validates that *max_len is large enough before writing any data.
References
Impacted products
Vendor Product Version
Linux Linux Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
Version: be6e8dc0ba84029997075a1ec77b4ddb863cbe15
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/export.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "60de2f55d2aca53e81b4ef2a67d7cc9e1eb677db",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "742b44342204e5dfe3926433823623c1a0c581df",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "d3a9a8e1275eb9b87f006b5562a287aea3f6885f",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "d91f6626133698362bba08fbc04bd72c466806d3",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "0276c8582488022f057b4cec21975a5edf079f47",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "361d67276eb8ec6be8f27f4ad6c6090459438fee",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "43143776b0a7604d873d1a6f3e552a00aa930224",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            },
            {
              "lessThan": "dff4f9ff5d7f289e4545cc936362e01ed3252742",
              "status": "affected",
              "version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/export.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.29"
            },
            {
              "lessThan": "2.6.29",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.301",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.246",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.195",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.54",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.4.301",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.246",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.195",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.157",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.113",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.54",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17.4",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18-rc1",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: avoid potential out-of-bounds in btrfs_encode_fh()\n\nThe function btrfs_encode_fh() does not properly account for the three\ncases it handles.\n\nBefore writing to the file handle (fh), the function only returns to the\nuser BTRFS_FID_SIZE_NON_CONNECTABLE (5 dwords, 20 bytes) or\nBTRFS_FID_SIZE_CONNECTABLE (8 dwords, 32 bytes).\n\nHowever, when a parent exists and the root ID of the parent and the\ninode are different, the function writes BTRFS_FID_SIZE_CONNECTABLE_ROOT\n(10 dwords, 40 bytes).\n\nIf *max_len is not large enough, this write goes out of bounds because\nBTRFS_FID_SIZE_CONNECTABLE_ROOT is greater than\nBTRFS_FID_SIZE_CONNECTABLE originally returned.\n\nThis results in an 8-byte out-of-bounds write at\nfid-\u003eparent_root_objectid = parent_root_id.\n\nA previous attempt to fix this issue was made but was lost.\n\nhttps://lore.kernel.org/all/4CADAEEC020000780001B32C@vpn.id2.novell.com/\n\nAlthough this issue does not seem to be easily triggerable, it is a\npotential memory corruption bug that should be fixed. This patch\nresolves the issue by ensuring the function returns the appropriate size\nfor all three cases and validates that *max_len is large enough before\nwriting any data."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-11-12T21:56:35.403Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/60de2f55d2aca53e81b4ef2a67d7cc9e1eb677db"
        },
        {
          "url": "https://git.kernel.org/stable/c/742b44342204e5dfe3926433823623c1a0c581df"
        },
        {
          "url": "https://git.kernel.org/stable/c/d3a9a8e1275eb9b87f006b5562a287aea3f6885f"
        },
        {
          "url": "https://git.kernel.org/stable/c/d91f6626133698362bba08fbc04bd72c466806d3"
        },
        {
          "url": "https://git.kernel.org/stable/c/0276c8582488022f057b4cec21975a5edf079f47"
        },
        {
          "url": "https://git.kernel.org/stable/c/361d67276eb8ec6be8f27f4ad6c6090459438fee"
        },
        {
          "url": "https://git.kernel.org/stable/c/43143776b0a7604d873d1a6f3e552a00aa930224"
        },
        {
          "url": "https://git.kernel.org/stable/c/dff4f9ff5d7f289e4545cc936362e01ed3252742"
        }
      ],
      "title": "btrfs: avoid potential out-of-bounds in btrfs_encode_fh()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40205",
    "datePublished": "2025-11-12T21:56:35.403Z",
    "dateReserved": "2025-04-16T07:20:57.179Z",
    "dateUpdated": "2025-11-12T21:56:35.403Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-40205\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-11-12T22:15:47.773\",\"lastModified\":\"2025-11-14T16:42:30.503\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbtrfs: avoid potential out-of-bounds in btrfs_encode_fh()\\n\\nThe function btrfs_encode_fh() does not properly account for the three\\ncases it handles.\\n\\nBefore writing to the file handle (fh), the function only returns to the\\nuser BTRFS_FID_SIZE_NON_CONNECTABLE (5 dwords, 20 bytes) or\\nBTRFS_FID_SIZE_CONNECTABLE (8 dwords, 32 bytes).\\n\\nHowever, when a parent exists and the root ID of the parent and the\\ninode are different, the function writes BTRFS_FID_SIZE_CONNECTABLE_ROOT\\n(10 dwords, 40 bytes).\\n\\nIf *max_len is not large enough, this write goes out of bounds because\\nBTRFS_FID_SIZE_CONNECTABLE_ROOT is greater than\\nBTRFS_FID_SIZE_CONNECTABLE originally returned.\\n\\nThis results in an 8-byte out-of-bounds write at\\nfid-\u003eparent_root_objectid = parent_root_id.\\n\\nA previous attempt to fix this issue was made but was lost.\\n\\nhttps://lore.kernel.org/all/4CADAEEC020000780001B32C@vpn.id2.novell.com/\\n\\nAlthough this issue does not seem to be easily triggerable, it is a\\npotential memory corruption bug that should be fixed. This patch\\nresolves the issue by ensuring the function returns the appropriate size\\nfor all three cases and validates that *max_len is large enough before\\nwriting any data.\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0276c8582488022f057b4cec21975a5edf079f47\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/361d67276eb8ec6be8f27f4ad6c6090459438fee\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/43143776b0a7604d873d1a6f3e552a00aa930224\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/60de2f55d2aca53e81b4ef2a67d7cc9e1eb677db\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/742b44342204e5dfe3926433823623c1a0c581df\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d3a9a8e1275eb9b87f006b5562a287aea3f6885f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d91f6626133698362bba08fbc04bd72c466806d3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/dff4f9ff5d7f289e4545cc936362e01ed3252742\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


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.