---
id: CVE-2026-89830
title: |-
  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_val…
summary: |-
  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_val…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 <
    2d50b6d47e5671ff6a25834c5906d443356191f0
  - >-
    Linux >= 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 <
    dde99df5a9d3b0ca6ac0a86f98799685f7399432
  - >-
    Linux >= 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 <
    931e1aa4d44c52ff8e0feb38420a8827c62e886b
  - >-
    Linux >= 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 <
    0f9af07ecc1ab486038373db6ae0436c5d674b19
  - Linux 6.9
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T11:16:49.753'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89830'
references:
  - url: 'https://git.kernel.org/stable/c/0f9af07ecc1ab486038373db6ae0436c5d674b19'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/2d50b6d47e5671ff6a25834c5906d443356191f0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/931e1aa4d44c52ff8e0feb38420a8827c62e886b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/dde99df5a9d3b0ca6ac0a86f98799685f7399432'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T10:53:54.000Z'
epss: 0.00209
epssPercentile: 0.09854
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.