CVE Catalog

CVE-2026-80530

HighCVSS 7.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel XFS filesystem, during exchange-range operations with the XFS_EXCHMAPS_INO1_WRITTEN flag, the function xmi_can_exchange_reflink_flags() may move the reflink flag to another file, but not all mappings are exchanged, which can lead to clearing the reflink flag on a file that still has shared written extents. This can result in data corruption. The fix disables the reflink flag exchange when XFS_EXCHMAPS_INO1_WRITTEN is requested.

Risk Assessment

The vulnerability can lead to data corruption in reflink-related files, potentially resulting in loss of data integrity.

Recommendation

Apply a Linux kernel update containing the fix. Avoid using exchange-range operations with the XFS_EXCHMAPS_INO1_WRITTEN flag on untrusted filesystems.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: xfs: fix exchange-range reflink flag clearing issue with INO1_WRITTEN When exchanging two full-file ranges, xmi_can_exchange_reflink_flags() can move the reflink inode flag from the file that currently has it to the other file, as long as exactly one side is marked. This assumes that the file contents, and therefore all shared extents, are exchanged. That assumption is not true when XFS_EXCHMAPS_INO1_WRITTEN is set. xfs_exchmaps_can_skip_mapping() can skip hole and unwritten mappings from file1, so an exchange can complete without moving every mapping that the earlier flag-swap decision accounted for. In that case the post-operation cleanup can clear the reflink flag from an inode that still owns shared written extents. Later writes then take the non-reflink write path and may update blocks that should still have been protected by CoW, which shows up as data corruption between reflink-related files. Fix this by disabling the reflink flag exchange whenever XFS_EXCHMAPS_INO1_WRITTEN is requested. The contents exchange can still proceed; the conservative outcome is that both inodes keep the reflink flag. The regular reflink flag cleanup path can drop the extra flag later once the inode no longer has shared extents.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS