---
id: CVE-2026-98201
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  Input: zero ff_effect before compat copy in input_ff_effect_from_user

  In the compat path input_ff_effect_from_user() aliases the caller's
  native struct ff_effect with …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  Input: zero ff_effect before compat copy in input_ff_effect_from_user

  In the compat path input_ff_effect_from_user() aliases the caller's
  native struct ff_effect with …
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    ed0905fda39682d3da7937184397d3276abbffa8
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    ec174c2ab1abb76b20fa167c6db848c3d97aa838
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    6c26681c5668c973bd0e951407d670ac60d9cd66
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    c5e573bb095d502be7cbbaa99c26a20984111c6d
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    b878720e8bcaa4cf7163a5081f904dd6baf11b2c
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    0d05b43b55d4784a42ce8fb318175f8ad7d9af5a
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    ed0406e490f48ed180df140fe2a81be26bccb1a9
  - >-
    Linux >= 2d56f3a32c0e62f99c043d2579840f9731fe5855 <
    f84819ef8d66931ee3998fee3c4f03230f4cb6cc
  - Linux 2.6.29
published: '2026-10-06'
updated: '2026-10-06'
sourceUpdated: '2026-10-06T09:18:05.900'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98201'
references:
  - url: 'https://git.kernel.org/stable/c/0d05b43b55d4784a42ce8fb318175f8ad7d9af5a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6c26681c5668c973bd0e951407d670ac60d9cd66'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b878720e8bcaa4cf7163a5081f904dd6baf11b2c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c5e573bb095d502be7cbbaa99c26a20984111c6d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ec174c2ab1abb76b20fa167c6db848c3d97aa838'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ed0406e490f48ed180df140fe2a81be26bccb1a9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ed0905fda39682d3da7937184397d3276abbffa8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f84819ef8d66931ee3998fee3c4f03230f4cb6cc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-10-06T08:50:17.445Z'
---

## Overview

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

Input: zero ff_effect before compat copy in input_ff_effect_from_user

In the compat path input_ff_effect_from_user() aliases the caller's
native struct ff_effect with the smaller struct ff_effect_compat and
copies only the compat sized prefix:

	compat_effect = (struct ff_effect_compat *)effect;

	if (copy_from_user(compat_effect, buffer,
			   sizeof(struct ff_effect_compat)))

The tail of the native structure is never written. Callers pass an
uninitialized on-stack object, for example evdev_do_ioctl() for
EVIOCSFF, so those bytes keep their previous stack contents.
input_ff_upload() then stores the full native structure in
ff->effects[id], from where a uinput based force feedback daemon can
read it back via UI_BEGIN_FF_UPLOAD, disclosing kernel stack memory to
userspace.

Zero the effect before the compat copy.

## Remediation

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