xfs: resample the data fork mapping after cycling ILOCK
Summary
| CVE | CVE-2026-64600 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-23 06:16:50 UTC |
| Updated | 2026-08-18 12:38:12 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: xfs: resample the data fork mapping after cycling ILOCK xfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode, a data fork mapping, and a cow fork mapping. Unfortunately, these two helpers cycle the ILOCK to grab a transaction, which means that the mappings are stale as soon as we reacquire the ILOCK. Currently we refresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but we don't refresh the data fork mapping beforehand, which means that the xfs_bmap_trim_cow in that function queries the refcount btree about the wrong physical blocks and returns an inaccurate value in *shared. If *shared is now false, the directio write proceeds with a stale data fork mapping. Fix this by querying the data fork mapping if the sequence counter changes across the ILOCK cycle. |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.005070000 probability, percentile 0.409510000 (date 2026-08-17)
Problem Types: CWE-362
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 dc11be133efca5fe3a2fb02b016dee825cc12f18 git | Not specified |
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 b8c9aa832b52680ee40d6cab0efb081f9a69df05 git | Not specified |
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 50f0012da1040f69a4e788cd9aed587c9a04983f git | Not specified |
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 e705d81a7193dd19e69b8e2bad4696d78a4ea075 git | Not specified |
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 206c09b04dc5469c7ff14d8aceff2d47c88078d9 git | Not specified |
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 44f891bc088958399eec27f7604928694aa35581 git | Not specified |
| CNA | Linux | Linux | affected 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 2f4acd0fcd862e22eab45690ec2c08c80b6ef2e7 git | Not specified |
| CNA | Linux | Linux | affected 4.11 | Not specified |
| CNA | Linux | Linux | unaffected 4.11 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.212 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.178 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.145 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.96 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.39 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.4 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| cdn2.qualys.com/advisory/2026/07/22/RefluXFS.txt | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | cdn2.qualys.com | Exploit, Third Party Advisory |
| git.kernel.org/stable/c/50f0012da1040f69a4e788cd9aed587c9a04983f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| www.openwall.com/lists/oss-security/2026/07/22/14 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List, Exploit |
| www.openwall.com/lists/oss-security/2026/07/31/3 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| www.openwall.com/lists/oss-security/2026/08/03/4 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| www.openwall.com/lists/oss-security/2026/08/03/8 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| git.kernel.org/stable/c/2f4acd0fcd862e22eab45690ec2c08c80b6ef2e7 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/b8c9aa832b52680ee40d6cab0efb081f9a69df05 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/44f891bc088958399eec27f7604928694aa35581 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/dc11be133efca5fe3a2fb02b016dee825cc12f18 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/e705d81a7193dd19e69b8e2bad4696d78a4ea075 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| www.openwall.com/lists/oss-security/2026/07/22/19 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| git.kernel.org/stable/c/206c09b04dc5469c7ff14d8aceff2d47c88078d9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| www.openwall.com/lists/oss-security/2026/07/22/18 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.