---
id: CVE-2026-53110
title: 's390/bpf: Zero-extend bpf prog return values and kfunc arguments'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  s390/bpf: Zero-extend bpf prog return values and kfunc arguments

  s390x ABI requires callers to zero-extend unsigned arguments and
  sign-extend signed arguments, and cal…
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'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba <
    edc90a12073b9a530064a99945c183dde120cb99
  - >-
    Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba <
    44c4f999b03f55debb1a0c5ab5c1796895a1adf8
  - >-
    Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba <
    366b0e05ee24f5ba62bdc7ec1346038258b9a797
  - >-
    Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba <
    834918a77be51419383bf1dda9f02b81ecf26b34
  - >-
    Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba <
    202e42e4aa890172366354b233c42c73107a3f59
  - Linux 6.3
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:25:44.899680Z'
published: '2026-06-24'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:31:33.021Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-53110'
references:
  - url: 'https://git.kernel.org/stable/c/edc90a12073b9a530064a99945c183dde120cb99'
  - url: 'https://git.kernel.org/stable/c/44c4f999b03f55debb1a0c5ab5c1796895a1adf8'
  - url: 'https://git.kernel.org/stable/c/366b0e05ee24f5ba62bdc7ec1346038258b9a797'
  - url: 'https://git.kernel.org/stable/c/834918a77be51419383bf1dda9f02b81ecf26b34'
  - url: 'https://git.kernel.org/stable/c/202e42e4aa890172366354b233c42c73107a3f59'
tags:
  - cve.org
epss: 0.0012
epssPercentile: 0.01677
ingestedAt: '2026-10-16T17:24:46.732Z'
---

## Overview

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

s390/bpf: Zero-extend bpf prog return values and kfunc arguments

s390x ABI requires callers to zero-extend unsigned arguments and
sign-extend signed arguments, and callees to zero-extend unsigned
return values and sign-extend signed return values.

s390 BPF JIT currently implements only sign extension. Fix this
omission and implement zero extension too.

## Affected

- `Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba < edc90a12073b9a530064a99945c183dde120cb99`
- `Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba < 44c4f999b03f55debb1a0c5ab5c1796895a1adf8`
- `Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba < 366b0e05ee24f5ba62bdc7ec1346038258b9a797`
- `Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba < 834918a77be51419383bf1dda9f02b81ecf26b34`
- `Linux >= 528eb2cb87bc1353235a6384696b4849bde8b0ba < 202e42e4aa890172366354b233c42c73107a3f59`
- `Linux 6.3`

## Remediation

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