High 7.8Published Dec 4, 2025

CVE-2025-40233ocfs2: clear extent cache after moving/defragmenting extents

Updated under an hour ago (Oct 26, 2026, 10:50 PM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: ocfs2: clear extent cache after moving/defragmenting extents The extent map cache can become stale when extents are moved or defragmented, causing subsequent operations to see outdated extent flags. This triggers a BUG_ON in ocfs2_refcount_cal_cow_clusters(). The problem occurs when: 1. copy_file_range() creates a reflinked extent with OCFS2_EXT_REFCOUNTED 2. ioctl(FITRIM) triggers ocfs2_move_extents() 3. __ocfs2_move_extents_range() reads and caches the extent (flags=0x2) 4. ocfs2_move_extent()/ocfs2_defrag_extent() calls __ocfs2_move_extent() which clears OCFS2_EXT_REFCOUNTED flag on disk (flags=0x0) 5. The extent map cache is not invalidated after the move 6. Later write() operations read stale cached flags (0x2) but disk has updated flags (0x0), causing a mismatch 7. BUG_ON(!(rec->e_flags & OCFS2_EXT_REFCOUNTED)) triggers Fix by clearing the extent map cache after each extent move/defrag operation in __ocfs2_move_extents_range(). This ensures subsequent operations read fresh extent data from disk.

CVSS: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Deferred
Record last updated: Aug 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 53069d4e76954e2e63c1b3c501051c6fbcf7298c before 93166bc53c0e3587058327a4121daea34b4fecd5; from 53069d4e76954e2e63c1b3c501051c6fbcf7298c before a7ee72286efba1d407c6f15a0528e43593fb7007; 53069d4e76954e2e63c1b3c501051c6fbcf7298c builds before 93b1ab422f1966b71561158e1aedce4ec100f357; from 53069d4e76954e2e63c1b3c501051c6fbcf7298c before e92af7737a94a729225d2a5d180eaaa77fe0bbc1; from 53069d4e76954e2e63c1b3c501051c6fbcf7298c before aa6a21409dd6221bb268b56bb410e031c632ff9a; from 53069d4e76954e2e63c1b3c501051c6fbcf7298c before bb69928ed578f881e68d26aaf1a8f6e7faab3b44; from 53069d4e76954e2e63c1b3c501051c6fbcf7298c before a21750df2f6169af6e039a3bb4893d6c9564e48d; 53069d4e76954e2e63c1b3c501051c6fbcf7298c builds before 78a63493f8e352296dbc7cb7b3f4973105e8679e	CNA record

References

References

https://git.kernel.org/stable/c/93166bc53c0e3587058327a4121daea34b4fecd5
https://git.kernel.org/stable/c/a7ee72286efba1d407c6f15a0528e43593fb7007
https://git.kernel.org/stable/c/93b1ab422f1966b71561158e1aedce4ec100f357
https://git.kernel.org/stable/c/e92af7737a94a729225d2a5d180eaaa77fe0bbc1
https://git.kernel.org/stable/c/aa6a21409dd6221bb268b56bb410e031c632ff9a
https://git.kernel.org/stable/c/bb69928ed578f881e68d26aaf1a8f6e7faab3b44
https://git.kernel.org/stable/c/a21750df2f6169af6e039a3bb4893d6c9564e48d
https://git.kernel.org/stable/c/78a63493f8e352296dbc7cb7b3f4973105e8679e

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.