---
id: CVE-2025-39827
title: 'net: rose: include node references in rose_neigh refcount'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: rose: include node references in rose_neigh refcount

  Current implementation maintains two separate reference counting
  mechanisms: the 'count' field in struct rose…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    4cce478c3e82a5fc788d72adb2f4c4e983997639
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    9c547c8eee9d1cf6e744611d688b9f725cf9a115
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    d7563b456ed44151e1a82091d96f60166daea89b
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    384210cceb1873a4c8218b27ba0745444436b728
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    da9c9c877597170b929a6121a68dcd3dd9a80f45
  - Linux 2.6.12
published: '2025-09-16'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T08:42:23.155Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-39827'
references:
  - url: 'https://git.kernel.org/stable/c/4cce478c3e82a5fc788d72adb2f4c4e983997639'
  - url: 'https://git.kernel.org/stable/c/9c547c8eee9d1cf6e744611d688b9f725cf9a115'
  - url: 'https://git.kernel.org/stable/c/d7563b456ed44151e1a82091d96f60166daea89b'
  - url: 'https://git.kernel.org/stable/c/384210cceb1873a4c8218b27ba0745444436b728'
  - url: 'https://git.kernel.org/stable/c/da9c9c877597170b929a6121a68dcd3dd9a80f45'
tags:
  - cve.org
epss: 0.00211
epssPercentile: 0.10142
ingestedAt: '2026-09-08T15:33:26.996Z'
---

## Overview

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

net: rose: include node references in rose_neigh refcount

Current implementation maintains two separate reference counting
mechanisms: the 'count' field in struct rose_neigh tracks references from
rose_node structures, while the 'use' field (now refcount_t) tracks
references from rose_sock.

This patch merges these two reference counting systems using 'use' field
for proper reference management. Specifically, this patch adds incrementing
and decrementing of rose_neigh->use when rose_neigh->count is incremented
or decremented.

This patch also modifies rose_rt_free(), rose_rt_device_down() and
rose_clear_route() to properly release references to rose_neigh objects
before freeing a rose_node through rose_remove_node().

These changes ensure rose_neigh structures are properly freed only when
all references, including those from rose_node structures, are released.
As a result, this resolves a slab-use-after-free issue reported by Syzbot.

## Affected

- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4cce478c3e82a5fc788d72adb2f4c4e983997639`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9c547c8eee9d1cf6e744611d688b9f725cf9a115`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d7563b456ed44151e1a82091d96f60166daea89b`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 384210cceb1873a4c8218b27ba0745444436b728`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < da9c9c877597170b929a6121a68dcd3dd9a80f45`
- `Linux 2.6.12`

## Remediation

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