---
id: CVE-2026-64465
title: 'usb: xhci: Fix sleep in atomic context in xhci_free_streams()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  usb: xhci: Fix sleep in atomic context in xhci_free_streams()

  When a USB device with active stream endpoints is disconnected,
  xhci_free_streams() is called from the hu…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    e623e4a203f56d5c57519a9a3cb29600551534ad
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    d107eb316144c5fb958486e7fe604cd7f1b35cda
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    1e45aa722c4ce5663e987102aac18c8ad6a83fdd
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    10666ac9c552990204e791af653abf8e9d9ff619
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    f7b022ae07685e7526fc39f387ce65b5d309dd3b
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    f90586129cf9e1fbdb718ef602eea3f15dc1c31c
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    93cd037da94fcb93183bfb2457e3a56d3eb4c8f4
  - >-
    Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 <
    42c37c4b75d38b51d84f31a8e29427f5e06a7c2a
  - Linux 2.6.35
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:39:09.199017Z'
published: '2026-07-25'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T16:44:53.011Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-64465'
references:
  - url: 'https://git.kernel.org/stable/c/e623e4a203f56d5c57519a9a3cb29600551534ad'
  - url: 'https://git.kernel.org/stable/c/d107eb316144c5fb958486e7fe604cd7f1b35cda'
  - url: 'https://git.kernel.org/stable/c/1e45aa722c4ce5663e987102aac18c8ad6a83fdd'
  - url: 'https://git.kernel.org/stable/c/10666ac9c552990204e791af653abf8e9d9ff619'
  - url: 'https://git.kernel.org/stable/c/f7b022ae07685e7526fc39f387ce65b5d309dd3b'
  - url: 'https://git.kernel.org/stable/c/f90586129cf9e1fbdb718ef602eea3f15dc1c31c'
  - url: 'https://git.kernel.org/stable/c/93cd037da94fcb93183bfb2457e3a56d3eb4c8f4'
  - url: 'https://git.kernel.org/stable/c/42c37c4b75d38b51d84f31a8e29427f5e06a7c2a'
tags:
  - cve.org
epss: 0.00184
epssPercentile: 0.08086
ingestedAt: '2026-11-06T16:57:43.171Z'
---

## Overview

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

usb: xhci: Fix sleep in atomic context in xhci_free_streams()

When a USB device with active stream endpoints is disconnected,
xhci_free_streams() is called from the hub_event workqueue to
free the stream resources.  It calls xhci_free_stream_info()
while holding xhci->lock with irqs disabled.

xhci_free_stream_info() invokes xhci_free_stream_ctx(), which
calls dma_free_coherent() for large stream context arrays.

dma_free_coherent() can sleep (e.g. via vunmap), triggering
a BUG when called from atomic context.

Call trace:
 dma_free_attrs+0x174/0x220
 xhci_free_stream_info+0xd0/0x11c
 xhci_free_streams+0x278/0x37c
 usb_free_streams+0x98/0xc0
 usb_unbind_interface+0x1b8/0x2f8
 device_release_driver_internal+0x1d4/0x2cc
 device_release_driver+0x18/0x28
 bus_remove_device+0x160/0x1a4
 device_del+0x1ec/0x350
 usb_disable_device+0x98/0x214
 usb_disconnect+0xf0/0x35c
 hub_event+0xab4/0x19ec
 process_one_work+0x278/0x63c

Fix this by saving the stream_info pointers and clearing the
ep references under the lock, then calling xhci_free_stream_info()
outside the lock where sleeping is allowed.

## Affected

- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < e623e4a203f56d5c57519a9a3cb29600551534ad`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < d107eb316144c5fb958486e7fe604cd7f1b35cda`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < 1e45aa722c4ce5663e987102aac18c8ad6a83fdd`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < 10666ac9c552990204e791af653abf8e9d9ff619`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < f7b022ae07685e7526fc39f387ce65b5d309dd3b`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < f90586129cf9e1fbdb718ef602eea3f15dc1c31c`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < 93cd037da94fcb93183bfb2457e3a56d3eb4c8f4`
- `Linux >= 8df75f42f8e67e2851cdcf6da91640fb881defd1 < 42c37c4b75d38b51d84f31a8e29427f5e06a7c2a`
- `Linux 2.6.35`

## Remediation

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