---
id: CVE-2026-98254
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  swiotlb: use the adjusted address for the highmem page lookup

  swiotlb_bounce() reads the page frame number from the slot's recorded
  orig_addr, then advances orig_addr …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  swiotlb: use the adjusted address for the highmem page lookup

  swiotlb_bounce() reads the page frame number from the slot's recorded
  orig_addr, then advances orig_addr …
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 >= 5f89468e2f060031cd89fd4287298e0eaf246bf6 <
    6e53b4d6afbde626255805d438cabb1cac482445
  - >-
    Linux >= 5f89468e2f060031cd89fd4287298e0eaf246bf6 <
    aa4709813b29db89f2307f968db5d24925dcdeb1
  - >-
    Linux >= 5f89468e2f060031cd89fd4287298e0eaf246bf6 <
    0219b72f5c209732b2f03a8cc0d7240b5e428a99
  - >-
    Linux >= 5f89468e2f060031cd89fd4287298e0eaf246bf6 <
    b7d7914a9ae3097e63d113007e4fb44d33d515b1
  - Linux e6108147dd91b94d1979b110f265710c254c99d5
  - Linux e77b796eb9b7ca3c1c0d574d0c155f55b59ca8d5
  - Linux >= 5.10.47 < 5.11
  - Linux >= 5.12.14 < 5.13
  - Linux 5.13
published: '2026-10-06'
updated: '2026-10-07'
sourceUpdated: '2026-10-07T07:17:06.683'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98254'
references:
  - url: 'https://git.kernel.org/stable/c/0219b72f5c209732b2f03a8cc0d7240b5e428a99'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6e53b4d6afbde626255805d438cabb1cac482445'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/aa4709813b29db89f2307f968db5d24925dcdeb1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b7d7914a9ae3097e63d113007e4fb44d33d515b1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00175
epssPercentile: 0.06379
ingestedAt: '2026-10-06T08:50:17.429Z'
---

## Overview

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

swiotlb: use the adjusted address for the highmem page lookup

swiotlb_bounce() reads the page frame number from the slot's recorded
orig_addr, then advances orig_addr by tlb_offset to reach the address
the caller asked about. The highmem branch mixes the two: the offset
within the page comes from the adjusted address, the page from the value
before it.

Once the adjustment crosses a page boundary the pair no longer describes
one location, and the whole copy lands one page below the intended one
for a positive tlb_offset, one above for a negative one. DMA_FROM_DEVICE
writes the device data over the wrong page and leaves the intended one
stale, DMA_TO_DEVICE feeds the device from a page the mapping may not
cover. Partial syncs through dma_sync_single_range_for_*() are what make
tlb_offset non-zero.

The branch test is picked the same way, so a slot recorded in lowmem can
be adjusted into highmem and the lowmem path then hands a highmem
address to phys_to_virt().

Take both from orig_addr once it is final and keep pfn in the branch
that uses it. PhysHighMem() asks the question straight from the address,
as dma-debug already does.

## Remediation

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