---
id: CVE-2024-26671
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  blk-mq: fix IO hang from sbitmap wakeup race

  In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered
  with the following blk_mq_get_driver_tag() in case of gett…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  blk-mq: fix IO hang from sbitmap wakeup race

  In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered
  with the following blk_mq_get_driver_tag() in case of gett…
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-362
vendor: linux
product: linux_kernel
affected:
  - linux_kernel < 4.19.307
  - 'linux_kernel >= 4.20, < 5.4.269'
  - 'linux_kernel >= 5.5, < 5.10.210'
  - 'linux_kernel >= 5.11, < 5.15.149'
  - 'linux_kernel >= 5.16, < 6.1.77'
  - 'linux_kernel >= 6.2, < 6.7.4'
  - debian_linux = 10.0
patched:
  - linux_kernel 6.7.4
published: '2024-04-02'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T01:17:22.260'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2024-26671'
references:
  - url: 'https://git.kernel.org/stable/c/1d9c777d3e70bdc57dddf7a14a80059d65919e56'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5266caaf5660529e3da53004b8b7174cab6374ed'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6d8b01624a2540336a32be91f25187a433af53a0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7610ba1319253225a9ba8a9d28d472fc883b4e2f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/89e0e66682e1538aeeaa3109503473663cd24c8b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9525b38180e2753f0daa1a522b7767a2aa969676'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ecd7744a1446eb02ccc63e493e2eb6ede4ef1e10'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f1bc0d8163f8ee84a8d5affdf624cfad657df1d2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/1d9c777d3e70bdc57dddf7a14a80059d65919e56'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/5266caaf5660529e3da53004b8b7174cab6374ed'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/6d8b01624a2540336a32be91f25187a433af53a0'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/7610ba1319253225a9ba8a9d28d472fc883b4e2f'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/89e0e66682e1538aeeaa3109503473663cd24c8b'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/9525b38180e2753f0daa1a522b7767a2aa969676'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/ecd7744a1446eb02ccc63e493e2eb6ede4ef1e10'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://git.kernel.org/stable/c/f1bc0d8163f8ee84a8d5affdf624cfad657df1d2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-613116.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00186
epssPercentile: 0.081
ingestedAt: '2026-10-15T03:30:12.646Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-09-10T15:53:32.693372Z'
---

## Overview

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

blk-mq: fix IO hang from sbitmap wakeup race

In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered
with the following blk_mq_get_driver_tag() in case of getting driver
tag failure.

Then in __sbitmap_queue_wake_up(), waitqueue_active() may not observe
the added waiter in blk_mq_mark_tag_wait() and wake up nothing, meantime
blk_mq_mark_tag_wait() can't get driver tag successfully.

This issue can be reproduced by running the following test in loop, and
fio hang can be observed in < 30min when running it on my test VM
in laptop.

	modprobe -r scsi_debug
	modprobe scsi_debug delay=0 dev_size_mb=4096 max_queue=1 host_max_queue=1 submit_queues=4
	dev=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/* | head -1 | xargs basename`
	fio --filename=/dev/"$dev" --direct=1 --rw=randrw --bs=4k --iodepth=1 \
       		--runtime=100 --numjobs=40 --time_based --name=test \
        	--ioengine=libaio

Fix the issue by adding one explicit barrier in blk_mq_mark_tag_wait(), which
is just fine in case of running out of tag.

## Affected

- `linux_kernel < 4.19.307`
- `linux_kernel >= 4.20, < 5.4.269`
- `linux_kernel >= 5.5, < 5.10.210`
- `linux_kernel >= 5.11, < 5.15.149`
- `linux_kernel >= 5.16, < 6.1.77`
- `linux_kernel >= 6.2, < 6.7.4`
- `debian_linux = 10.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.7.4`