---
id: CVE-2026-97441
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ata: ahci: fail probe if BAR too small for claimed ports

  When an AHCI controller is disabled in BIOS, its HOST_CAP register may
  contain a bogus value, e.g
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ata: ahci: fail probe if BAR too small for claimed ports

  When an AHCI controller is disabled in BIOS, its HOST_CAP register may
  contain a bogus value, e.g. 0xFFFFFFFF.…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-125
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    533a08ea11217100cec7a0ed903cb9b9c892d6f1
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    c717b20100ef8cd06b5237af70ea2cb692e058ce
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    ff0ab535f8febbd32afa5832f8d2d9b06a8d5060
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    6d29b91164424256a759ddabc8f2de1ae09bd3f1
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    df262c828b616450eb351349e91c63447551bd01
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    f2e291043c37a896d7f9797e25a356dceb030177
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    c4086c6e1af757e1ff26fa2d2926b3ec0195de79
  - Linux 2.6.12
published: '2026-09-24'
updated: '2026-10-03'
sourceUpdated: '2026-10-03T11:17:55.757'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97441'
references:
  - url: 'https://git.kernel.org/stable/c/533a08ea11217100cec7a0ed903cb9b9c892d6f1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6d29b91164424256a759ddabc8f2de1ae09bd3f1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c4086c6e1af757e1ff26fa2d2926b3ec0195de79'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c717b20100ef8cd06b5237af70ea2cb692e058ce'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/df262c828b616450eb351349e91c63447551bd01'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f2e291043c37a896d7f9797e25a356dceb030177'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ff0ab535f8febbd32afa5832f8d2d9b06a8d5060'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97441.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-97441'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2540552'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-97441'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97441'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97441.mbox
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00173
epssPercentile: 0.06619
cvssSource: vendor
ingestedAt: '2026-09-24T16:47:15.878Z'
---

## Overview

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

ata: ahci: fail probe if BAR too small for claimed ports

When an AHCI controller is disabled in BIOS, its HOST_CAP register may
contain a bogus value, e.g. 0xFFFFFFFF.

Since CAP.NP (Number of Ports) is a zeroes based 5-bit register field,
a value of 0x1f means 32 ports. If CAP.NP claims more ports than can
physically fit within the mapped BAR region, accessing port registers
beyond the BAR boundary causes a kernel panic.

Add validation in ahci_init_one() to check that the BAR size is
sufficient for the number of ports claimed in CAP.NP. The check
calculates the required MMIO size as:

  required_size = 0x100 (global registers) + max_ports * 0x80

If required_size exceeds the actual BAR size, the probe fails with
-ENODEV, preventing the panic and providing a clear error message.

[cassel: commit log]

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-29 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97441.json)