---
id: CVE-2026-97421
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()

  Several corner cases, especially important on 32 bits:

  - umem->iova is u64, the function a…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()

  Several corner cases, especially important on 32 bits:

  - umem->iova is u64, the function a…
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'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    ae3cf7d2c4d506c5c91746321644e1a08d989e2a
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    5fc5b73109540809b094710fac44da81dd8a3ff8
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    09ea6837a0434fb4db99528a5055b6d822135dcf
  - Linux < 6.12.111
  - Linux < 6.18.53
  - Linux (all versions)
published: '2026-09-24'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T13:17:25.643'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97421'
references:
  - url: 'https://git.kernel.org/stable/c/09ea6837a0434fb4db99528a5055b6d822135dcf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5fc5b73109540809b094710fac44da81dd8a3ff8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ae3cf7d2c4d506c5c91746321644e1a08d989e2a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-24T16:47:15.884Z'
epss: 0.00127
epssPercentile: 0.02007
---

## Overview

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

RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()

Several corner cases, especially important on 32 bits:

- umem->iova is u64, the function argument should pass in u64 or
  iova will be truncated
- Check that the length is not too large for the iova
- Check that lengths > 4G don't overflow the GENMASK

## Remediation

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