{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/iomap/buffered-io.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0c6cf409093f307ee05114f834516730c0da5b21",
              "status": "affected",
              "version": "38be53c3fd7f4f4bd5de319a323d72f9f6beb16d",
              "versionType": "git"
            },
            {
              "lessThan": "5c281b0c5d18c8eeb1cfd5023f4adb153e6d1240",
              "status": "affected",
              "version": "f43dc4dc3eff028b5ddddd99f3a66c5a6bdd4e78",
              "versionType": "git"
            },
            {
              "lessThan": "eee2d2e6ea5550118170dbd5bb1316ceb38455fb",
              "status": "affected",
              "version": "f43dc4dc3eff028b5ddddd99f3a66c5a6bdd4e78",
              "versionType": "git"
            },
            {
              "lessThan": "6.1.162",
              "status": "affected",
              "version": "6.1.92",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/iomap/buffered-io.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.2"
            },
            {
              "lessThan": "6.2",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.162",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.5.*",
              "status": "unaffected",
              "version": "6.5.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.6",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.162",
                  "versionStartIncluding": "6.1.92",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.5.5",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niomap: Fix possible overflow condition in iomap_write_delalloc_scan\n\nfolio_next_index() returns an unsigned long value which left shifted\nby PAGE_SHIFT could possibly cause an overflow on 32-bit system. Instead\nuse folio_pos(folio) + folio_size(folio), which does this correctly."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The flaw is reached through a local `write()`/`pwrite()` syscall on a buffered file on an iomap/XFS filesystem, via `iomap_file_buffered_write()` \u2192 `xfs_buffered_write_iomap_end()` \u2192 `iomap_write_delalloc_release()`. No network-facing service reliably produces the required short-write-with-partial-copy condition, so local access is needed.\nAC:L - The attacker deterministically controls every trigger condition: creating a file larger than 4 GiB, dirtying folios above that offset, and forcing a short write by passing a buffer that straddles an unmapped/PROT_NONE page so `fault_in_iov_iter_readable()` fails. On the affected deployment class (32-bit ARM/x86 embedded, industrial and NAS devices running XFS) the 32-bit truncation is a fixed property of the target, not a race or a condition outside attacker control.\nPR:L - Only an unprivileged local account with write access to any file on an XFS filesystem (e.g. /tmp, /var, or a home directory) is required. No capability, root, or namespace trickery is needed anywhere along the `vfs_write` \u2192 iomap path.\nUI:N - The attacker performs the entire sequence \u2014 extending the file past 4 GiB, dirtying page cache, issuing the faulting write \u2014 in its own process. No victim action or cooperation is required.\nS:U - The overflow and its effects are confined to the kernel\u0027s own filesystem/page-cache state on the same system; no VM, IOMMU, or sandbox security boundary is crossed.\nC:N - The miscalculation only causes delalloc (unwritten reservation) extents to be removed; `xfs_bmap_punch_delalloc_range()` explicitly skips real allocated extents via the `isnullstartblock()` check, so no out-of-bounds read occurs and punched ranges read back as zeroes rather than exposing stale disk or kernel memory.\nI:H - The wrapped `punch_start_byte` causes delalloc reservations to be punched over a range up to ~4 GiB below the intended one, leaving dirty page-cache data with no backing reservation; `xfs_map_blocks()` then finds a hole at writeback and the data is silently discarded, permanently destroying file contents \u2014 including data written concurrently by other users to a shared file \u2014 and leaving the on-disk extent state inconsistent with the page cache.\nA:H - The corrupted punch range trips `WARN_ON_ONCE(start_byte \u003c punch_start_byte)` (a panic under `panic_on_warn`) and drives writeback into holes, producing XFS writeback errors and filesystem shutdown that renders the volume unusable; on affected kernels the same 32-bit truncation in the adjacent loop-advance expression additionally yields an unkillable infinite loop while holding `i_rwsem` and the mapping invalidate lock, permanently wedging the inode and burning a CPU."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:18:57.424Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/0c6cf409093f307ee05114f834516730c0da5b21"
        },
        {
          "url": "https://git.kernel.org/stable/c/5c281b0c5d18c8eeb1cfd5023f4adb153e6d1240"
        },
        {
          "url": "https://git.kernel.org/stable/c/eee2d2e6ea5550118170dbd5bb1316ceb38455fb"
        }
      ],
      "title": "iomap: Fix possible overflow condition in iomap_write_delalloc_scan",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-54285",
    "datePublished": "2025-12-30T12:23:25.770Z",
    "dateReserved": "2025-12-30T12:06:44.526Z",
    "dateUpdated": "2026-08-05T09:18:57.424Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}