---
id: CVE-2026-74346
title: 'RDMA/irdma: Fix OOB read during CQ MR registration'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  RDMA/irdma: Fix OOB read during CQ MR registration

  Sashiko pointed out an unrelated bug during a previous patch:
  https://sashiko.dev/#/patchset/20260512183852.614045-1…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    a80b3b13786e9ab1c52b31a1f16c7d6708fa9220
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    3159c6fac43dc24b34d31971884d98a7a1bf4c4b
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    ad360a31092a870633ec255b96f50181628b4de0
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    d566002de555b18cc395012c5c1cb8682fc6d2a9
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    54cab78df0375196aaec4e3109191653d21751df
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    d5aa82da8f65562da996d184686db9d0ea718b91
  - >-
    Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 <
    4385ddd654d90245eeb83b3cb539670ab5c85ba4
  - Linux 5.14
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:56:22.704059Z'
published: '2026-08-15'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T17:05:44.518Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74346'
references:
  - url: 'https://git.kernel.org/stable/c/a80b3b13786e9ab1c52b31a1f16c7d6708fa9220'
  - url: 'https://git.kernel.org/stable/c/3159c6fac43dc24b34d31971884d98a7a1bf4c4b'
  - url: 'https://git.kernel.org/stable/c/ad360a31092a870633ec255b96f50181628b4de0'
  - url: 'https://git.kernel.org/stable/c/d566002de555b18cc395012c5c1cb8682fc6d2a9'
  - url: 'https://git.kernel.org/stable/c/54cab78df0375196aaec4e3109191653d21751df'
  - url: 'https://git.kernel.org/stable/c/d5aa82da8f65562da996d184686db9d0ea718b91'
  - url: 'https://git.kernel.org/stable/c/4385ddd654d90245eeb83b3cb539670ab5c85ba4'
tags:
  - cve.org
epss: 0.00173
epssPercentile: 0.06704
ingestedAt: '2026-11-06T18:00:12.562Z'
---

## Overview

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

RDMA/irdma: Fix OOB read during CQ MR registration

Sashiko pointed out an unrelated bug during a previous patch:
https://sashiko.dev/#/patchset/20260512183852.614045-1-jmoroni%40google.com

This change fixes the bug by eliminating the cqmr->split field which
was not being set properly and instead just checks the CQ resize
feature flag directly.

The cqmr->split field essentially tracks whether IRDMA_FEATURE_CQ_RESIZE
is set, but it was not being set until CQ creation time, which is _after_
CQ memory registration (the only other place where it is referenced).

As a result, it would always be false during MR registration and would
therefore cause irdma_handle_q_mem to populate cqmr->shadow even for GEN_2
HW and beyond:

    cqmr->shadow = (dma_addr_t)arr[req->cq_pages];

The issue is that for GEN_2 and beyond, req->cq_pages may be exactly equal
to iwmr->page_cnt and therefore equal to the size of arr, which would cause
an OOB read by one.

## Affected

- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < a80b3b13786e9ab1c52b31a1f16c7d6708fa9220`
- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < 3159c6fac43dc24b34d31971884d98a7a1bf4c4b`
- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < ad360a31092a870633ec255b96f50181628b4de0`
- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < d566002de555b18cc395012c5c1cb8682fc6d2a9`
- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < 54cab78df0375196aaec4e3109191653d21751df`
- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < d5aa82da8f65562da996d184686db9d0ea718b91`
- `Linux >= b48c24c2d710cf34810c555dcef883a3d35a9c08 < 4385ddd654d90245eeb83b3cb539670ab5c85ba4`
- `Linux 5.14`

## Remediation

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