---
id: CVE-2026-43061
title: 'serial: 8250: Fix TX deadlock when using DMA'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  serial: 8250: Fix TX deadlock when using DMA

  `dmaengine_terminate_async` does not guarantee that the
  `__dma_tx_complete` callback will run. The callback is currently t…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 7c47e637dfadfbc691dd297b91d81ef939ca2080 <
    8190f9ab6ad90cb97652adbebd238b874a4ef70d
  - >-
    Linux >= bf3f395b9c37956eca866c9e1679769ed7dcce68 <
    79a19bd936bb35f56ef0ccab1b3b59ebce8c762d
  - >-
    Linux >= d470522c597b73e63cca04f3012aec28185113b7 <
    f76d91271bcacbd759a2e4ee3ea61faa6a727ccf
  - >-
    Linux >= 5e00346deb7bf40a4cf70e3716ac8e9a2409eb55 <
    d2719a0a9c3439abf67843a5504b7afccd9ded93
  - >-
    Linux >= c8a52c772c7c6de72257a435bcad03d3bb914a70 <
    2a72403b985aea6b4aac3171830492f9a387f9e1
  - >-
    Linux >= 9e512eaaf8f4008c44ede3dfc0fbc9d9c5118583 <
    5f6b17562f03fc65c7d3474ef8f1959b19d1ca41
  - >-
    Linux >= 9e512eaaf8f4008c44ede3dfc0fbc9d9c5118583 <
    b5ad887339503103d0fbe9827b16ad287597c275
  - >-
    Linux >= 9e512eaaf8f4008c44ede3dfc0fbc9d9c5118583 <
    a424a34b8faddf97b5af41689087e7a230f79ba7
  - Linux bbec5998d7bd349730f59c959a8b00cfff816e34
  - Linux 59f751db7f392fa7a58cbd972205982f7f4f5854
  - Linux >= 5.10.235 < 5.10.253
  - Linux >= 5.15.179 < 5.15.203
  - Linux >= 6.1.129 < 6.1.167
  - Linux >= 6.6.79 < 6.6.130
  - Linux >= 6.12.16 < 6.12.78
  - Linux >= 5.4.291 < 5.5
  - Linux >= 6.13.4 < 6.14
  - Linux 6.14
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T15:27:37.230216Z'
published: '2026-05-05'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T15:32:29.243Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-43061'
references:
  - url: 'https://git.kernel.org/stable/c/8190f9ab6ad90cb97652adbebd238b874a4ef70d'
  - url: 'https://git.kernel.org/stable/c/79a19bd936bb35f56ef0ccab1b3b59ebce8c762d'
  - url: 'https://git.kernel.org/stable/c/f76d91271bcacbd759a2e4ee3ea61faa6a727ccf'
  - url: 'https://git.kernel.org/stable/c/d2719a0a9c3439abf67843a5504b7afccd9ded93'
  - url: 'https://git.kernel.org/stable/c/2a72403b985aea6b4aac3171830492f9a387f9e1'
  - url: 'https://git.kernel.org/stable/c/5f6b17562f03fc65c7d3474ef8f1959b19d1ca41'
  - url: 'https://git.kernel.org/stable/c/b5ad887339503103d0fbe9827b16ad287597c275'
  - url: 'https://git.kernel.org/stable/c/a424a34b8faddf97b5af41689087e7a230f79ba7'
tags:
  - cve.org
epss: 0.00091
epssPercentile: 0.00462
ingestedAt: '2026-11-06T15:54:04.029Z'
---

## Overview

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

serial: 8250: Fix TX deadlock when using DMA

`dmaengine_terminate_async` does not guarantee that the
`__dma_tx_complete` callback will run. The callback is currently the
only place where `dma->tx_running` gets cleared. If the transaction is
canceled and the callback never runs, then `dma->tx_running` will never
get cleared and we will never schedule new TX DMA transactions again.

This change makes it so we clear `dma->tx_running` after we terminate
the DMA transaction. This is "safe" because `serial8250_tx_dma_flush`
is holding the UART port lock. The first thing the callback does is also
grab the UART port lock, so access to `dma->tx_running` is serialized.

## Affected

- `Linux >= 7c47e637dfadfbc691dd297b91d81ef939ca2080 < 8190f9ab6ad90cb97652adbebd238b874a4ef70d`
- `Linux >= bf3f395b9c37956eca866c9e1679769ed7dcce68 < 79a19bd936bb35f56ef0ccab1b3b59ebce8c762d`
- `Linux >= d470522c597b73e63cca04f3012aec28185113b7 < f76d91271bcacbd759a2e4ee3ea61faa6a727ccf`
- `Linux >= 5e00346deb7bf40a4cf70e3716ac8e9a2409eb55 < d2719a0a9c3439abf67843a5504b7afccd9ded93`
- `Linux >= c8a52c772c7c6de72257a435bcad03d3bb914a70 < 2a72403b985aea6b4aac3171830492f9a387f9e1`
- `Linux >= 9e512eaaf8f4008c44ede3dfc0fbc9d9c5118583 < 5f6b17562f03fc65c7d3474ef8f1959b19d1ca41`
- `Linux >= 9e512eaaf8f4008c44ede3dfc0fbc9d9c5118583 < b5ad887339503103d0fbe9827b16ad287597c275`
- `Linux >= 9e512eaaf8f4008c44ede3dfc0fbc9d9c5118583 < a424a34b8faddf97b5af41689087e7a230f79ba7`
- `Linux bbec5998d7bd349730f59c959a8b00cfff816e34`
- `Linux 59f751db7f392fa7a58cbd972205982f7f4f5854`
- `Linux >= 5.10.235 < 5.10.253`
- `Linux >= 5.15.179 < 5.15.203`
- `Linux >= 6.1.129 < 6.1.167`
- `Linux >= 6.6.79 < 6.6.130`
- `Linux >= 6.12.16 < 6.12.78`
- `Linux >= 5.4.291 < 5.5`
- `Linux >= 6.13.4 < 6.14`
- `Linux 6.14`

## Remediation

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