---
id: "CVE-2026-98645"
kind: "vulnerability"
aliases: ["CVE-2026-98645"]
title: "Linux kernel: WinWing HID force-feedback teardown double-frees memory on unbind"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["hid", "kernel", "linux", "runtime", "winwing"]
not_affected_if: ["driver-not-loaded", "no-winwing-device"]
published_at: "2026-10-18T16:17:17+00:00"
first_seen_at: "2026-10-23T21:57:16+00:00"
updated_at: "2026-10-25T05:20:49+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98645", "first_seen_at": "2026-10-23T21:57:16+00:00"}]
---

# Linux kernel: WinWing HID force-feedback teardown double-frees memory on unbind

The WinWing HID driver in the Linux kernel passes devres-managed memory to the force-feedback core, which frees it with kfree() on device teardown. The same allocation is then freed again by devres, causing a use-after-free and double free that can corrupt kernel memory.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check whether the WinWing HID driver (hid-winwing) is loaded with `lsmod | grep winwing`
- Check the kernel version with `uname -r` and compare against the fixed release in the NVD entry unknown

## Fix

- Update the Linux kernel to a release that includes the upstream commit fixing HID: winwing force-feedback teardown (version unknown from the sources)

## Timeline

- 2026-10-23T21:57:16+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98645

## From the sources

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

HID: winwing: fix use-after-free in force feedback teardown

winwing_init_ff() passes the driver's private data, allocated with
devm_kzalloc() in winwing_probe(), as the effect context to
input_ff_create_memless(). The memoryless force-feedback core takes
ownership of that pointer and frees it with kfree() from
input_ff_destroy() (ml_ff_destroy()) when the input device is
destroyed.

Freeing a devm-managed allocation with kfree() is an invalid free, and
the same object is then released again by devres when the HID device is
torn down, a double free. As the allocation also embeds the LED class
devices, their timers and work item live on freed memory and the slab
gets corrupted. This triggers on unbind, rmmod, hot-unplug and on system
suspend, where the firmware cache walks the now-corrupt devres list.
KASAN reports:

  BUG: KASAN: invalid-free in input_ff_destroy
  Allocated by task N:
    winwing_probe

Pass NULL as the memless context instead and fetch the driver data from
the input device in winwing_play_effect(): the HID core already stores
the hid_device as the input device's drvdata. The force-feedback core
then owns nothing that it must not free.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_