{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f0bc4d134b46607967bda1205ce3226a1bd95f42"
            },
            {
              "fixed": "1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be"
            },
            {
              "fixed": "7d3b9b2c9dc57f93f36c716ab752548cb4db9900"
            },
            {
              "fixed": "4756c94260e69ce42612b8220c3614f02f7a11d5"
            },
            {
              "fixed": "d84d6c1a7f1e2de9e601703a326a4c1b7b421943"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.9.0"
            },
            {
              "fixed": "6.12.114"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.57"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98975.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: stop exchanging reflink flags when exchanging mappings\n\nWhen an exchange covers both files from offset 0 to i_disk_size,\nxmi_can_exchange_reflink_flags() assumes every mapping moved and hands\nthe reflink flag over to the other file.\n\nThat assumption is wrong.  A file can still own shared blocks past\ni_disk_size, e.g. after EXCHANGE_RANGE_TO_EOF sets a smaller size\nwithout unmapping anything.  The flag is cleared anyway, and the next\nwrite to such a block happens in place instead of CoW, corrupting the\nother file that shares it.\n\nCommit a23eca88448e (\"xfs: fix exchange-range reflink flag clearing\nissue with INO1_WRITTEN\") fixed one instance of this.  Rather than add\nanother special case, stop moving the flags.\nxfs_exchmaps_ensure_reflink() already sets the flag on both inodes\nbefore the exchange, so both just keep it.\n\nNothing sets CLEAR_INO{1,2}_REFLINK anymore.  Intents logged by older\nkernels may still carry them; recovery already masks them off, so they\nstay in the log format mask and are ignored.\n\nXFS_IOC_SWAPEXT has the same problem: it moves the reflink flag from\none inode to the other along with the extents.  Just removing that is\nnot enough here: the exchange path flags both inodes up front in\nxfs_exchmaps_ensure_reflink(), but swapext has no such step, so the\ninode receiving the shared extents would be left without the flag.\nSet it on both inodes instead, and make sure both have a CoW fork,\nsince an inode with the reflink flag is expected to have one.\n\nThe flag now stays until FALLOC_FL_UNSHARE_RANGE, xfs_scrub, or a\ntruncate to zero removes it.",
  "id": "CVE-2026-98975",
  "modified": "2026-10-28T02:30:43.727276263Z",
  "published": "2026-10-23T12:19:48.379Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4756c94260e69ce42612b8220c3614f02f7a11d5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7d3b9b2c9dc57f93f36c716ab752548cb4db9900"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d84d6c1a7f1e2de9e601703a326a4c1b7b421943"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98975.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98975"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "xfs: stop exchanging reflink flags when exchanging mappings"
}