---
id: CVE-2026-74397
title: 'IB/mlx5: Fix transport-domain rollback and initialize lb mutex earlier'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  IB/mlx5: Fix transport-domain rollback and initialize lb mutex earlier

  mlx5_ib_alloc_transport_domain() allocates a transport domain and then
  may fail in mlx5_ib_enabl…
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'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d <
    2c3b2667dad69d56774b79db763acb3a1bee0fc0
  - >-
    Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d <
    37fc3cc0f924fd8d0f0cf87b92672dec75a32e57
  - >-
    Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d <
    65e344925fa30abf50c8de8c150b397715fa2066
  - >-
    Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d <
    f88e12c95fc19f719e06ca1e9eb20fdad68ef61a
  - >-
    Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d <
    e79389115b9d27287ff6230a9750675106ed7668
  - Linux 4.5
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T18:55:25.351057Z'
published: '2026-08-15'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T19:05:41.192Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74397'
references:
  - url: 'https://git.kernel.org/stable/c/2c3b2667dad69d56774b79db763acb3a1bee0fc0'
  - url: 'https://git.kernel.org/stable/c/37fc3cc0f924fd8d0f0cf87b92672dec75a32e57'
  - url: 'https://git.kernel.org/stable/c/65e344925fa30abf50c8de8c150b397715fa2066'
  - url: 'https://git.kernel.org/stable/c/f88e12c95fc19f719e06ca1e9eb20fdad68ef61a'
  - url: 'https://git.kernel.org/stable/c/e79389115b9d27287ff6230a9750675106ed7668'
tags:
  - cve.org
epss: 0.00175
epssPercentile: 0.06546
ingestedAt: '2026-10-16T19:46:24.369Z'
---

## Overview

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

IB/mlx5: Fix transport-domain rollback and initialize lb mutex earlier

mlx5_ib_alloc_transport_domain() allocates a transport domain and then
may fail in mlx5_ib_enable_lb(). In that case, the allocated TD is leaked.

Fix this by deallocating the TD when mlx5_ib_enable_lb() returns an
error. Also return 0 explicitly in the no-loopback-capability success
branch, and move dev->lb.mutex initialization to mlx5_ib_stage_init_init().

## Affected

- `Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d < 2c3b2667dad69d56774b79db763acb3a1bee0fc0`
- `Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d < 37fc3cc0f924fd8d0f0cf87b92672dec75a32e57`
- `Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d < 65e344925fa30abf50c8de8c150b397715fa2066`
- `Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d < f88e12c95fc19f719e06ca1e9eb20fdad68ef61a`
- `Linux >= 146d2f1af3245a10b13eef263687e54f4e253d1d < e79389115b9d27287ff6230a9750675106ed7668`
- `Linux 4.5`

## Remediation

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