---
cve: "CVE-2026-89830"
severity: "LOW"
cvss: 3.1
epss: "0.2%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-09-16 11:16:49"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T18:47:18+02:00"
---

# CVE-2026-89830

> 3.1 LOW

## Beschreibung

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix valid block count leak on data block allocation failure

In __allocate_data_block(), when allocating a new data block
(dn->data_blkaddr == NULL_ADDR), inc_valid_block_count() is
called first to increment total_valid_block_count and i_blocks.
If the subsequent f2fs_allocate_data_block() fails, the function
returns the error directly without rolling back the
already-incremented block counts, causing a permanent leak.

Fix this by calling dec_valid_block_count() to undo the
increment before returning the error. The condition
old_blkaddr == NULL_ADDR precisely identifies the case where
inc_valid_block_count() was called.

## Patch verfügbar (OSV)

- Kernel ≥ 6.12.110
- Kernel ≥ 6.18.51
- Kernel ≥ 7.2.5

## Referenzen

- <https://git.kernel.org/stable/c/2d50b6d47e5671ff6a25834c5906d443356191f0>
- <https://git.kernel.org/stable/c/dde99df5a9d3b0ca6ac0a86f98799685f7399432>
- <https://git.kernel.org/stable/c/931e1aa4d44c52ff8e0feb38420a8827c62e886b>
- <https://git.kernel.org/stable/c/0f9af07ecc1ab486038373db6ae0436c5d674b19>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-89830) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_