---
id: CVE-2026-90035
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/amd/display: fix division by zero in get_estimated_bw()

  get_estimated_bw() divides by link->dpia_bw_alloc_config.bw_granularity,
  which is zeroed by reset_bw_alloc_…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/amd/display: fix division by zero in get_estimated_bw()

  get_estimated_bw() divides by link->dpia_bw_alloc_config.bw_granularity,
  which is zeroed by reset_bw_alloc_…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8e5cfe547bf3beeb29d9608be68d22dff2b5012b <
    4c5b61b9df6ab33b55f228e1b6579cefad11a9f7
  - >-
    Linux >= 8e5cfe547bf3beeb29d9608be68d22dff2b5012b <
    ac2ab58a79bf2401ae8c5d1c030bf0a5a376f43a
  - >-
    Linux >= 8e5cfe547bf3beeb29d9608be68d22dff2b5012b <
    4814f28c45f58a71a80d09b80a60da6a063b539a
  - >-
    Linux >= 8e5cfe547bf3beeb29d9608be68d22dff2b5012b <
    b08c3d5ee7feadd821208f7c2c1ec02a16ce5878
  - >-
    Linux >= 8e5cfe547bf3beeb29d9608be68d22dff2b5012b <
    f63de9054da858d57054474c32464106f8375e0d
  - Linux 6.3
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T11:17:16.690'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90035'
references:
  - url: 'https://git.kernel.org/stable/c/4814f28c45f58a71a80d09b80a60da6a063b539a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4c5b61b9df6ab33b55f228e1b6579cefad11a9f7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ac2ab58a79bf2401ae8c5d1c030bf0a5a376f43a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b08c3d5ee7feadd821208f7c2c1ec02a16ce5878'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f63de9054da858d57054474c32464106f8375e0d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T10:53:53.932Z'
epss: 0.00186
epssPercentile: 0.07339
---

## Overview

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

drm/amd/display: fix division by zero in get_estimated_bw()

get_estimated_bw() divides by link->dpia_bw_alloc_config.bw_granularity,
which is zeroed by reset_bw_alloc_struct() and only populated once
DP_TUNNELING_BW_ALLOC_CAP_CHANGED has been handled.

link_dp_dpia_handle_bw_alloc_status(), the DPCD interrupt handler,
calls get_estimated_bw() whenever DP_TUNNELING_ESTIMATED_BW_CHANGED
is set, independently of whether DP_TUNNELING_BW_ALLOC_CAP_CHANGED
has ever fired for that link. A connected USB4/DPIA tunneling device
that reports an estimated-bandwidth change before ever reporting a
capability change drives a division by zero in this IRQ path.

link_dpia_send_bw_alloc_request() already guards the same
bw_granularity division; add the identical guard here rather than
introducing a new pattern.

(cherry picked from commit f2a961457c33dc34223aad5c9e8971de34a4eed3)

## Remediation

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