---
id: CVE-2026-90302
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ocfs2: synchronize heartbeat callbacks with o2net teardown

  Patch series "ocfs2: harden heartbeat teardown races".

  This series fixes two OCFS2 heartbeat/o2net teardown…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ocfs2: synchronize heartbeat callbacks with o2net teardown

  Patch series "ocfs2: harden heartbeat teardown races".

  This series fixes two OCFS2 heartbeat/o2net teardown…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    7601db4c9d3bd9ab2482a863cb05204154d51ae8
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    fb61882e184ee5ca745806bc5b2a8483fa129bca
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    a03078a9a2a1c5e4a62f65d389c1f75f9898e21d
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    cbb4efc2f99d6a8dba09c96b10acad82da982cf9
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    8f96b78314cff0778a3466e49e5edbc1e459c95c
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    aee687a2fb36974dc37e4e0f5b03802067c6c4ec
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    073f51e39bed354452a057d38a4cc3952727c304
  - >-
    Linux >= 98211489d4147e41b11703e4245846d60b3acce4 <
    3e326f3bf16506873777444608e8b715aab74a7a
  - Linux 2.6.16
published: '2026-09-17'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T17:17:27.723'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90302'
references:
  - url: 'https://git.kernel.org/stable/c/073f51e39bed354452a057d38a4cc3952727c304'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3e326f3bf16506873777444608e8b715aab74a7a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7601db4c9d3bd9ab2482a863cb05204154d51ae8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8f96b78314cff0778a3466e49e5edbc1e459c95c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a03078a9a2a1c5e4a62f65d389c1f75f9898e21d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/aee687a2fb36974dc37e4e0f5b03802067c6c4ec'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cbb4efc2f99d6a8dba09c96b10acad82da982cf9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/fb61882e184ee5ca745806bc5b2a8483fa129bca'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-17T16:21:47.829Z'
epss: 0.00211
epssPercentile: 0.11588
---

## Overview

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

ocfs2: synchronize heartbeat callbacks with o2net teardown

Patch series "ocfs2: harden heartbeat teardown races".

This series fixes two OCFS2 heartbeat/o2net teardown races found by
KASAN.


This patch (of 2):

Heartbeat callbacks stay registered while configfs local-node teardown
enters o2net_stop_listening().  A node-down event can still run through
o2net_disconnect_node() and o2net_set_nn_state() while teardown is
destroying o2net_wq, so the later queue/flush operations can hit a dead
workqueue.  KASAN has caught this as a slab-use-after-free in
__queue_work() with the call chain:

KASAN slab-use-after-free in __queue_work+0x56/0xa90
Read of size 4
Call trace:
  dump_stack_lvl+0x66/0xa0
  print_report+0xce/0x630
  __queue_work+0x56/0xa90
  srso_alias_return_thunk+0x5/0xfbef5
  __virt_addr_valid+0x19f/0x330
  kasan_report+0xe0/0x110
  __queue_delayed_work+0x58/0x1e0
  queue_delayed_work_on+0xb4/0xc0
  o2net_set_nn_state+0x467/0x840
  o2net_disconnect_node+0x7b/0xe0
  o2net_hb_node_down_cb+0x54/0x60
  o2hb_run_event_list+0x236/0x2d0
  o2hb_check_slot+0xad4/0xbc0
  lock_release+0xc8/0x290
  o2hb_check_slot+0x9ea/0xbc0
  trace_hardirqs_on+0x18/0x130
  o2hb_do_disk_heartbeat+0x646/0xb30 (fs/ocfs2/cluster/heartbeat.c:1079)
  __lock_acquire+0x466/0x2260
  lockdep_hardirqs_on_prepare+0xea/0x1a0
  ktime_get_with_offset+0xe9/0x230
  o2hb_thread+0x14e/0x770
  kthread+0x1ad/0x1f0
  ret_from_fork+0x3c9/0x540
  __switch_to+0x2e9/0x730
  ret_from_fork_asm+0x1a/0x30
Allocated by task stack:
  kasan_save_stack+0x33/0x60
  kasan_save_track+0x14/0x30
  __kasan_kmalloc+0xaa/0xb0
  __kmalloc_noprof+0x292/0x760
  __alloc_workqueue+0x736/0xc60
  alloc_workqueue_noprof+0xb1/0x110
  o2net_start_listening+0xe5/0x430
  o2nm_node_local_store+0x184/0x310
  configfs_write_iter+0x18a/0x210
  vfs_write+0x469/0x810
  ksys_write+0xd2/0x170
  do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
  entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task stack:
  kasan_save_stack+0x33/0x60
  kasan_save_track+0x14/0x30
  kasan_save_free_info+0x3b/0x60
  __kasan_slab_free+0x5f/0x80
  kfree+0x313/0x590
  rcu_core+0x4f4/0x1320
  handle_softirqs+0x156/0x660

queue_delayed_work_on
o2net_set_nn_state
o2net_disconnect_node
o2net_hb_node_down_cb
o2hb_run_event_list

Keep heartbeat callbacks registered so quorum state still tracks node
state, but stop them from driving o2net reconnect/disconnect work once
local teardown starts. Mark the transport offline before destroying
o2net_wq, wait for any in-flight heartbeat callback to finish, and delay
bring-up replay until the new local node is published through
o2nm_this_node().

The replay also has to stay serialized with heartbeat callback delivery.
Otherwise a live-node snapshot can be copied, a real hb_down callback
can install -ENOTCONN for a peer, and the stale replay can call
o2net_hb_node_up() for that same peer and queue reconnect work even
though heartbeat is already down.

The buggy scenario involves two paths, with each column showing the order
within that path:

local-node teardown:                 heartbeat node-down callback:
1. configfs local-off enters         1. o2hb_run_event_list() invokes
   o2net_stop_listening().              o2net_hb_node_down_cb().
2. teardown heads for                2. the callback reaches
   destroy_workqueue(o2net_wq).         o2net_disconnect_node() and
                                        o2net_set_nn_state().
3. teardown destroys and NULLs       3. the callback flushes or queues
   o2net_wq.                            work through o2net_wq.

## Remediation

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