---
id: CVE-2026-98951
title: 'riscv: ptrace: Zero-initialize regset buffers before copyin'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  riscv: ptrace: Zero-initialize regset buffers before copyin

  user_regset_copyin() only copies `count` bytes, so a PTRACE_SETREGSET
  request with a short iov_len leaves t…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 9300f00439743c4a34d735e1a27118eb68a1504e <
    89fc70d73f4ac8781f9e15edd1dbc6b6088453b3
  - >-
    Linux >= 9300f00439743c4a34d735e1a27118eb68a1504e <
    59052a88ba5fe4a7bb34b3a0a42aa5d453d3bb97
  - Linux f2a9cd050901c4734bc175294c3bd6a40a1a9e99
  - Linux >= 6.5.3 < 6.6
  - Linux 6.6
published: '2026-10-23'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T12:19:10.747Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-98951'
references:
  - url: 'https://git.kernel.org/stable/c/89fc70d73f4ac8781f9e15edd1dbc6b6088453b3'
  - url: 'https://git.kernel.org/stable/c/59052a88ba5fe4a7bb34b3a0a42aa5d453d3bb97'
tags:
  - cve.org
ingestedAt: '2026-10-23T13:24:55.558Z'
---

## Overview

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

riscv: ptrace: Zero-initialize regset buffers before copyin

user_regset_copyin() only copies `count` bytes, so a PTRACE_SETREGSET
request with a short iov_len leaves the rest of the stack buffer
uninitialized. In riscv_vr_set() that garbage is validated and copied
into the target's vstate, and in riscv_cfi_set() it can be stored as
the target's shadow stack pointer. Zero both buffers, as the get path
already does.

## Affected

- `Linux >= 9300f00439743c4a34d735e1a27118eb68a1504e < 89fc70d73f4ac8781f9e15edd1dbc6b6088453b3`
- `Linux >= 9300f00439743c4a34d735e1a27118eb68a1504e < 59052a88ba5fe4a7bb34b3a0a42aa5d453d3bb97`
- `Linux f2a9cd050901c4734bc175294c3bd6a40a1a9e99`
- `Linux >= 6.5.3 < 6.6`
- `Linux 6.6`

## Remediation

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