---
id: CVE-2026-74574
title: 'dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open()

  The failed_dev_add and failed_dev_name paths drop the file-device
  reference while wq->wq_lock is st…
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'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec <
    778ccbded2c8749c5be7f0dfa04fc9977a36fb7e
  - >-
    Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec <
    8d5d28285728be47c82fdf1c48be4268293c90e7
  - >-
    Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec <
    0679c0c189d2548f00e1bac95be28e2df5c6c7f7
  - >-
    Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec <
    6e26a41c4c1a706edaaa7c7dffc6b3b945707a55
  - >-
    Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec <
    ee1d7274102285d78a53161fc705a8d8cd40b066
  - Linux 6.4
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T19:00:43.194808Z'
published: '2026-08-15'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T19:05:57.115Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74574'
references:
  - url: 'https://git.kernel.org/stable/c/778ccbded2c8749c5be7f0dfa04fc9977a36fb7e'
  - url: 'https://git.kernel.org/stable/c/8d5d28285728be47c82fdf1c48be4268293c90e7'
  - url: 'https://git.kernel.org/stable/c/0679c0c189d2548f00e1bac95be28e2df5c6c7f7'
  - url: 'https://git.kernel.org/stable/c/6e26a41c4c1a706edaaa7c7dffc6b3b945707a55'
  - url: 'https://git.kernel.org/stable/c/ee1d7274102285d78a53161fc705a8d8cd40b066'
tags:
  - cve.org
epss: 0.00122
epssPercentile: 0.01825
ingestedAt: '2026-10-16T19:46:24.340Z'
---

## Overview

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

dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open()

The failed_dev_add and failed_dev_name paths drop the file-device
reference while wq->wq_lock is still held. If put_device(fdev) drops the
last reference, idxd_file_dev_release() runs synchronously and tries to
take wq->wq_lock again, deadlocking.

Those paths also fall through into the later ctx cleanup labels even
though idxd_file_dev_release() owns that cleanup and frees ctx. This can
make idxd_xa_pasid_remove(ctx) and kfree(ctx) operate on a freed context.

Move idxd_wq_get() before file-device setup can fail, since the release
callback always calls idxd_wq_put(). Then unlock wq->wq_lock before
put_device(fdev) and return directly from the file-device setup failure
path, leaving ctx cleanup to the release callback.

## Affected

- `Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec < 778ccbded2c8749c5be7f0dfa04fc9977a36fb7e`
- `Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec < 8d5d28285728be47c82fdf1c48be4268293c90e7`
- `Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec < 0679c0c189d2548f00e1bac95be28e2df5c6c7f7`
- `Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec < 6e26a41c4c1a706edaaa7c7dffc6b3b945707a55`
- `Linux >= e6fd6d7e5f0fe4a17a08e892afb5db800e7794ec < ee1d7274102285d78a53161fc705a8d8cd40b066`
- `Linux 6.4`

## Remediation

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