CVE-2026-89841

In the Linux kernel, the following vulnerability has been resolved: f2fs: only redirty pinned folios in redirty_blocks redirty_blocks() pins folios with read_cache_folio() and then walks the same range again with filemap_lock_folio() to redirty them and drop the references it took. Commit 5951fee46bef ("f2fs: Use a folio in redirty_blocks()") changed the second pass to a do/while loop. If read_cache_folio() fails before anything is pinned, page_idx does not advance but the cleanup loop still runs once. If readahead has already populated the failed folio in page cache, that extra iteration finds it and folio_put_refs(folio, 2) drops one reference too many. Later drop_caches or reclaim can then report "BUG: Bad page state". Only redirty the range that was pinned successfully.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/445e4a1e6025ecd5312e9a95c1b234192c976ca1
https://git.kernel.org/stable/c/85171332742e741ccd6f401c69b6e0d698119e72
https://git.kernel.org/stable/c/89c65ec3c18903de763cf567c96ab3ef60e5f3b0

Configurations

No configuration.

History

16 Sep 2026, 15:18

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.8

Information

Published : 2026-09-16 11:16

Updated : 2026-09-16 15:18

NVD link : CVE-2026-89841

Mitre link : CVE-2026-89841

CVE.ORG link : CVE-2026-89841

JSON object : View

Products Affected

No product.

CWE

No CWE.

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