---
id: CVE-2026-90001
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  HID: bpf: serialize device reference release in struct_ops destroy path

  __hid_bpf_ops_destroy_device() and hid_bpf_unreg() can race on the
  same registration reference,…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  HID: bpf: serialize device reference release in struct_ops destroy path

  __hid_bpf_ops_destroy_device() and hid_bpf_unreg() can race on the
  same registration reference,…
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 >= ebc0d8093e8c97de459615438edefad1a4ac352c <
    401359684620145be710de97b87e1a47abfe1459
  - >-
    Linux >= ebc0d8093e8c97de459615438edefad1a4ac352c <
    c7f927aa8b55008ed5ea0814313d5dad771dcf3c
  - >-
    Linux >= ebc0d8093e8c97de459615438edefad1a4ac352c <
    bfb7939788f3c8dd080a4dd81e38d625b35d194e
  - >-
    Linux >= ebc0d8093e8c97de459615438edefad1a4ac352c <
    9cdc7e6dc7a99ad7311ad5e7c145f2b9ce4e24b0
  - Linux 6.11
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:18:23.880'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90001'
references:
  - url: 'https://git.kernel.org/stable/c/401359684620145be710de97b87e1a47abfe1459'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9cdc7e6dc7a99ad7311ad5e7c145f2b9ce4e24b0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/bfb7939788f3c8dd080a4dd81e38d625b35d194e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c7f927aa8b55008ed5ea0814313d5dad771dcf3c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T10:53:53.946Z'
epss: 0.00163
epssPercentile: 0.05963
---

## Overview

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

HID: bpf: serialize device reference release in struct_ops destroy path

__hid_bpf_ops_destroy_device() and hid_bpf_unreg() can race on the
same registration reference, double-putting struct hid_device and
freeing it while hid_destroy_device() still uses it.  Serialize the
remove/NULL decision under hdev->bpf.prog_list_lock so exactly one
path releases each registration reference: unreg re-checks ops->hdev
under the lock and returns without putting when the destroy path
already cleared it; all put_device() calls happen after the lock is
dropped, which is safe because a concurrent unreg then observes
ops->hdev == NULL under the lock.

Background: each successful attach (hid_bpf_ops_reg) acquires one
device reference (hid_get_device()).  Two paths can release it:

- device destruction: hid_destroy_device() -> hid_bpf_destroy_device()
  -> __hid_bpf_ops_destroy_device(), which walks hdev->bpf.prog_list
  under rcu_read_lock() and drops one reference per attached program;
- BPF link release: bpf map delete (no BPF_F_LINK) synchronously calls
  st_ops->unreg() -> hid_bpf_unreg(), which drops the reference for
  its own registration.

The coordination handshake (e->hdev = NULL on the destroy side vs
"if (!hdev) return" on the unreg side) is a TOCTOU check: the two
paths run under different lock domains (rcu_read_lock vs
prog_list_lock), so a concurrent unreg can read ops->hdev as
non-NULL, block on prog_list_lock, and then proceed while the
destroy traversal executes - both paths then drop the same
reference.  The refcount reaches zero legitimately (each decrement
is individually valid), so no refcount_t saturation fires: the
device is simply freed while the transport is still inside
hid_destroy_device(), and subsequent teardown touches freed memory.

The fix serializes the remove/NULL decision under prog_list_lock on
both sides and moves the destroy-side puts outside the lock.  With
the lock held, plain reads/writes of ops->hdev are sufficient; no
READ_ONCE/WRITE_ONCE are added, keeping the patch minimal.

Unlocked-read safety: the unlocked read of ops->hdev at the top of
hid_bpf_unreg() cannot touch a freed device, because the unreg path
itself still holds this registration's reference (released only by
its own hid_put_device() after the lock is dropped), and a destroy
traversal that already cleared ops->hdev makes the lock-internal
re-check return early without any put.  At most one of the two
paths releases each registration reference.

## Remediation

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