---
id: CVE-2025-21832
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  block: don't revert iter for -EIOCBQUEUED

  blkdev_read_iter() has a few odd checks, like gating the position and
  count adjustment on whether or not the result is bigger…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  block: don't revert iter for -EIOCBQUEUED

  blkdev_read_iter() has a few odd checks, like gating the position and
  count adjustment on whether or not the result is bigger…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.17.1, < 6.1.129'
  - 'linux_kernel >= 6.2, < 6.6.78'
  - 'linux_kernel >= 6.7, < 6.12.14'
  - 'linux_kernel >= 6.13, < 6.13.3'
  - linux_kernel = 5.17
patched:
  - linux_kernel 6.13.3
published: '2025-03-06'
updated: '2026-07-30'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-21832'
references:
  - url: 'https://git.kernel.org/stable/c/68f16d3034a06661245ecd22f0d586a8b4e7c473'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6c26619effb1b4cb7d20b4e666ab8f71f6a53ccb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/84671b0630ccb46ae9f1f99a45c7d63ffcd6a474'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a58f136bad29f9ae721a29d98c042fddbee22f77'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b13ee668e8280ca5b07f8ce2846b9957a8a10853'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00188
epssPercentile: 0.07445
ingestedAt: '2026-07-30T06:53:10.380Z'
---

## Overview

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

block: don't revert iter for -EIOCBQUEUED

blkdev_read_iter() has a few odd checks, like gating the position and
count adjustment on whether or not the result is bigger-than-or-equal to
zero (where bigger than makes more sense), and not checking the return
value of blkdev_direct_IO() before doing an iov_iter_revert(). The
latter can lead to attempting to revert with a negative value, which
when passed to iov_iter_revert() as an unsigned value will lead to
throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT.

Be sane and don't revert for -EIOCBQUEUED, like what is done in other
spots.

## Affected

- `linux_kernel >= 5.17.1, < 6.1.129`
- `linux_kernel >= 6.2, < 6.6.78`
- `linux_kernel >= 6.7, < 6.12.14`
- `linux_kernel >= 6.13, < 6.13.3`
- `linux_kernel = 5.17`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.13.3`