CVE-2026-99242

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ntfs: fix race between fallocate and mmap reads The fallocate implementation only takes invalidate_lock for punch hole, collapse range, and insert range operations. For standard allocation modes (mode == 0, FALLOC_FL_KEEP_SIZE), the lock is not held. During ntfs_attr_fallocate(), new clusters are mapped to the runlist via ntfs_attr_map_cluster() before being zeroed by ntfs_dio_zero_range(). This creates a window where concurrent mmap page faults can read uninitialized disk data. Since mmap uses filemap_fault() which takes invalidate_lock in shared mode, it can fault in pages during this window and expose old disk contents to userspace. This is an information leak and data integrity issue. Fix by taking invalidate_lock for all fallocate operations, not just for punch/collapse/insert modes. This prevents concurrent page faults from accessing unzeroed clusters during the allocation window.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-11-02 16:17:50.040000

Last modified

2026-11-02 16:17:50.040000

View original CVE JSON

{
  "id": "CVE-2026-99242",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-11-02T16:17:50.040",
  "lastModified": "2026-11-02T16:17:50.040",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: fix race between fallocate and mmap reads\n\nThe fallocate implementation only takes invalidate_lock for punch hole,\ncollapse range, and insert range operations. For standard allocation modes\n(mode == 0, FALLOC_FL_KEEP_SIZE), the lock is not held.\n\nDuring ntfs_attr_fallocate(), new clusters are mapped to the runlist via\nntfs_attr_map_cluster() before being zeroed by ntfs_dio_zero_range(). This\ncreates a window where concurrent mmap page faults can read uninitialized\ndisk data.\n\nSince mmap uses filemap_fault() which takes invalidate_lock in shared mode,\nit can fault in pages during this window and expose old disk contents to\nuserspace. This is an information leak and data integrity issue.\n\nFix by taking invalidate_lock for all fallocate operations, not just for\npunch/collapse/insert modes. This prevents concurrent page faults from\naccessing unzeroed clusters during the allocation window."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/ntfs/file.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "495e90fa334828d4119061e2726af51d0a0fb4ed",
              "lessThan": "7dd1c2fec6ebdd1a88a02cb58ff515a258eeb327",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "495e90fa334828d4119061e2726af51d0a0fb4ed",
              "lessThan": "67aded1da114dc44808315f249bd9e7e440f799d",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/ntfs/file.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.14",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/67aded1da114dc44808315f249bd9e7e440f799d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7dd1c2fec6ebdd1a88a02cb58ff515a258eeb327",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}