---
id: CVE-2026-90044
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  usb: gadget: f_fs: Fix Use-After-Free in AIO error path

  In ffs_epfile_write_iter() and ffs_epfile_read_iter(), when ffs_epfile_io()
  fails with an error other than -EIO…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  usb: gadget: f_fs: Fix Use-After-Free in AIO error path

  In ffs_epfile_write_iter() and ffs_epfile_read_iter(), when ffs_epfile_io()
  fails with an error other than -EIO…
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
affected:
  - >-
    Linux >= de2080d41b5d584205e408d72021f0f335a046fc <
    153b5ecd29ed055562400bc17c91df3fd869b0ce
  - >-
    Linux >= de2080d41b5d584205e408d72021f0f335a046fc <
    4a2fb2d12b87b43724230abb52a1440617c7b6cc
  - >-
    Linux >= de2080d41b5d584205e408d72021f0f335a046fc <
    e78dcb1f7ec271449c54984dc90c62a5ba272de7
  - Linux 4.0
published: '2026-09-16'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T14:17:28.530'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90044'
references:
  - url: 'https://git.kernel.org/stable/c/153b5ecd29ed055562400bc17c91df3fd869b0ce'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4a2fb2d12b87b43724230abb52a1440617c7b6cc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b5f0e80a03e87bd932487e03248eae3ba3ed7b45'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e78dcb1f7ec271449c54984dc90c62a5ba272de7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00148
epssPercentile: 0.04391
ingestedAt: '2026-09-16T10:53:53.929Z'
---

## Overview

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

usb: gadget: f_fs: Fix Use-After-Free in AIO error path

In ffs_epfile_write_iter() and ffs_epfile_read_iter(), when ffs_epfile_io()
fails with an error other than -EIOCBQUEUED, the io_data structure (`p`) is
freed. However, for AIO operations, the kiocb cancel function was already
armed and kiocb->private was set to `p`.

If a concurrent cancel operation (such as sys_io_cancel()) executes after
ffs_epfile_io() fails but before the function frees `p`, a Use-After-Free
can occur when the cancellation handler accesses the freed pointer.

To securely fix this race condition, we must properly un-arm the
cancellation. Invoking `kiocb->ki_complete()` does exactly this by
acquiring `ctx->ctx_lock` and safely removing the kiocb from the active
sequence. In doing so, it ensures that a parallel io_cancel can no longer
discover the kiocb, effectively closing the race window.

We then return -EIOCBQUEUED to notify the VFS layer that the kiocb has been
consumed and it should avoid attempting to complete the request again or
triggering subsequent completion handlers.

## Remediation

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