---
id: CVE-2026-64438
title: 'crypto: qat - fix VF2PF work teardown race in adf_disable_sriov()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  crypto: qat - fix VF2PF work teardown race in adf_disable_sriov()

  The VF2PF interrupt handler queues PF-side response work that stores a
  raw pointer to per-VF state (s…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    218c2836b3987f3fa1d9eac505462cded0821e4c
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    446b4d77599cf1a168573f7fb32a4a6aa4f09219
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    5d916c1eae1933511a69bffe243b4ee5d7da399c
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    f344a369d0380d54c8d6c8d24734a78dd5a89817
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    51144032248cc4ea22917370565650670b8b4e9b
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    49cd5ac6de8de39a14ead609bb552d372d5602cd
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    6e92b28cd74fa433658efeadf21b9d4b01023d7d
  - >-
    Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 <
    277281c10c63791067d24d421f7c43a15faa9096
  - Linux 4.3
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:40:43.590817Z'
published: '2026-07-25'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:42:35.881Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-64438'
references:
  - url: 'https://git.kernel.org/stable/c/218c2836b3987f3fa1d9eac505462cded0821e4c'
  - url: 'https://git.kernel.org/stable/c/446b4d77599cf1a168573f7fb32a4a6aa4f09219'
  - url: 'https://git.kernel.org/stable/c/5d916c1eae1933511a69bffe243b4ee5d7da399c'
  - url: 'https://git.kernel.org/stable/c/f344a369d0380d54c8d6c8d24734a78dd5a89817'
  - url: 'https://git.kernel.org/stable/c/51144032248cc4ea22917370565650670b8b4e9b'
  - url: 'https://git.kernel.org/stable/c/49cd5ac6de8de39a14ead609bb552d372d5602cd'
  - url: 'https://git.kernel.org/stable/c/6e92b28cd74fa433658efeadf21b9d4b01023d7d'
  - url: 'https://git.kernel.org/stable/c/277281c10c63791067d24d421f7c43a15faa9096'
tags:
  - cve.org
epss: 0.00135
epssPercentile: 0.02629
ingestedAt: '2026-10-16T17:24:46.820Z'
---

## Overview

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

crypto: qat - fix VF2PF work teardown race in adf_disable_sriov()

The VF2PF interrupt handler queues PF-side response work that stores a
raw pointer to per-VF state (struct adf_accel_vf_info). Currently,
adf_disable_sriov() destroys per-VF mutexes and frees vf_info without
stopping new VF2PF work or waiting for in-flight workers to complete. A
concurrently scheduled or already queued worker can then dereference
freed memory.

This manifests as a use-after-free when KASAN is enabled:

  BUG: KASAN: null-ptr-deref in mutex_lock+0x76/0xe0
  Write of size 8 at addr 0000000000000260 by task kworker/24:2/...
  Workqueue: qat_pf2vf_resp_wq adf_iov_send_resp [intel_qat]
  Call Trace:
    kasan_report+0x119/0x140
    mutex_lock+0x76/0xe0
    adf_gen4_pfvf_send+0xd4/0x1f0 [intel_qat]
    adf_recv_and_handle_vf2pf_msg+0x290/0x360 [intel_qat]
    adf_iov_send_resp+0x8c/0xe0 [intel_qat]
    process_one_work+0x6ac/0xfd0
    worker_thread+0x4dd/0xd30
    kthread+0x326/0x410
    ret_from_fork+0x33b/0x670

Add a PF-local flag, vf2pf_disabled, that gates work queueing, worker
processing, and interrupt re-enabling during teardown. Set this flag
atomically with the hardware interrupt mask inside
adf_disable_all_vf2pf_interrupts(). After masking, synchronize the AE
cluster MSI-X interrupt and flush the PF response workqueue before
tearing down per-VF locks and state so all in-flight work completes
before vf_info is destroyed.

Introduce adf_enable_all_vf2pf_interrupts() to clear the flag and
unmask all VF2PF interrupts under the same lock when SR-IOV is
re-enabled. This ensures the software flag and hardware state transition
atomically on both the enable and disable paths.

## Affected

- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 218c2836b3987f3fa1d9eac505462cded0821e4c`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 446b4d77599cf1a168573f7fb32a4a6aa4f09219`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 5d916c1eae1933511a69bffe243b4ee5d7da399c`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < f344a369d0380d54c8d6c8d24734a78dd5a89817`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 51144032248cc4ea22917370565650670b8b4e9b`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 49cd5ac6de8de39a14ead609bb552d372d5602cd`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 6e92b28cd74fa433658efeadf21b9d4b01023d7d`
- `Linux >= ed8ccaef52fa03fb03cff45b380f72c9f869f273 < 277281c10c63791067d24d421f7c43a15faa9096`
- `Linux 4.3`

## Remediation

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