---
id: CVE-2026-80589
title: 'block: stop the timeout timer when releasing a never added disk'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  block: stop the timeout timer when releasing a never added disk

  disk_release() undoes blk_mq_init_allocated_queue() for a disk whose
  probe failed before add_disk(), bu…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 <
    6ae7364f68e6c7af6b6df4bbb14040b89e5975d0
  - >-
    Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 <
    6f06dbe5012c160e0dba418a5a9cb16c456ad46a
  - >-
    Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 <
    1a0ae4d502062a2759f2a92d12bdeab3c64c7372
  - >-
    Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 <
    bb03b56d1d754908a37a160603be21769da423cf
  - >-
    Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 <
    93d620519d71dfc6ee64b5baea74f1d85d4439fb
  - >-
    Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 <
    26cb8ebbfaf713c82e142d08828d4d765057633b
  - Linux d27b66257db183fe11c10f31246ae965adb005d3
  - Linux >= 5.19.12 < 5.20
  - Linux 6.0
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T19:18:09.871712Z'
published: '2026-08-26'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T19:26:29.099Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-80589'
references:
  - url: 'https://git.kernel.org/stable/c/6ae7364f68e6c7af6b6df4bbb14040b89e5975d0'
  - url: 'https://git.kernel.org/stable/c/6f06dbe5012c160e0dba418a5a9cb16c456ad46a'
  - url: 'https://git.kernel.org/stable/c/1a0ae4d502062a2759f2a92d12bdeab3c64c7372'
  - url: 'https://git.kernel.org/stable/c/bb03b56d1d754908a37a160603be21769da423cf'
  - url: 'https://git.kernel.org/stable/c/93d620519d71dfc6ee64b5baea74f1d85d4439fb'
  - url: 'https://git.kernel.org/stable/c/26cb8ebbfaf713c82e142d08828d4d765057633b'
tags:
  - cve.org
epss: 0.0037
epssPercentile: 0.29399
ingestedAt: '2026-10-16T19:46:24.310Z'
---

## Overview

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

block: stop the timeout timer when releasing a never added disk

disk_release() undoes blk_mq_init_allocated_queue() for a disk whose
probe failed before add_disk(), but it only calls blk_mq_exit_queue().
Nothing there stops q->timeout, and that timer rolls forward: it stays
pending until it next expires, not until the last request completes.
So if the driver issued any I/O before adding the disk, the
request_queue is freed while still linked into a timer wheel bucket.

Commit 6f8191fdf41d ("block: simplify disk shutdown") dropped the
blk_cleanup_queue() call that used to stop it.  __del_gendisk() and
blk_mq_destroy_queue() still do; only the probe failure path lost it.

nvme gets there because nvme_update_ns_info() submits Report Zones or
FDP io-mgmt-recv on ns->queue before the disk is added, so a later
failure - a concurrent reset setting NVME_CTRL_FROZEN, or
device_add_disk() failing - lands in put_disk() with the timer armed:

  BUG: KASAN: slab-use-after-free in detach_if_pending+0x30c/0x340
  Write of size 8 at addr ffff888004d71310 by task kworker/u8:2/37
   __timer_delete_sync+0x156/0x240 kernel/time/timer.c:1621
   blk_sync_queue+0x22/0x40 block/blk-core.c:222
   nvme_sync_queues+0x100/0x150 drivers/nvme/host/core.c:5362
   nvme_reset_work+0x138/0x930 drivers/nvme/host/pci.c:3264

  Allocated by task 34:
   __blk_mq_alloc_disk+0x33/0x100 block/blk-mq.c:4462
   nvme_alloc_ns+0x290/0x3870 drivers/nvme/host/core.c:4146

  Freed by task 0:
   blk_free_queue_rcu+0x3a/0x50 block/blk-core.c:254
   rcu_core+0xc10/0x1730 kernel/rcu/tree.c:2857

The queue being synced there is ctrl->admin_q, only a victim sharing a
timer wheel bucket with the freed queue's dangling entry; other runs
tripped in enqueue_timer(), __run_timers() or blk_mq_timeout_work().
Failing nvme_alloc_ns() with a debug patch makes it deterministic: one
leaked timer trips KASAN within seconds, while 1987 patched releases
produced no splat.

Stop the timer and the queue work items before blk_mq_exit_queue(), like
blk_mq_destroy_queue() does.

Found by FuzzNvme.

## Affected

- `Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 < 6ae7364f68e6c7af6b6df4bbb14040b89e5975d0`
- `Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 < 6f06dbe5012c160e0dba418a5a9cb16c456ad46a`
- `Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 < 1a0ae4d502062a2759f2a92d12bdeab3c64c7372`
- `Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 < bb03b56d1d754908a37a160603be21769da423cf`
- `Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 < 93d620519d71dfc6ee64b5baea74f1d85d4439fb`
- `Linux >= 6f8191fdf41d3a53cc1d63fe2234e812c55a0092 < 26cb8ebbfaf713c82e142d08828d4d765057633b`
- `Linux d27b66257db183fe11c10f31246ae965adb005d3`
- `Linux >= 5.19.12 < 5.20`
- `Linux 6.0`

## Remediation

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