---
id: CVE-2026-45891
title: 'net: hns3: fix double free issue for tx spare buffer'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: hns3: fix double free issue for tx spare buffer

  In hns3_set_ringparam(), a temporary copy (tmp_rings) of the ring structure
  is created for rollback. However, the …
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    fb6a4c376d454b425555b1b0bda36e99f56ec307
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    43015461662d41dcfb3bb95fadd8a2a42ad8eacf
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    6dc10494cfe27b6f1e9adb7e293293ae39c50b7c
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    d2c785733dfb853ea0b53984c75662a1af230a94
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    fdbccddb7e7822016601829f95de4008e193f7bc
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    c3659273860bed0c8e573b865e3769abc51225a8
  - >-
    Linux >= 907676b130711fd1f627824559e92259db2061d1 <
    6d2f142b1e4b203387a92519d9d2e34752a79dbb
  - Linux 5.14
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T15:43:41.206482Z'
published: '2026-05-27'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T15:53:11.090Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-45891'
references:
  - url: 'https://git.kernel.org/stable/c/fb6a4c376d454b425555b1b0bda36e99f56ec307'
  - url: 'https://git.kernel.org/stable/c/43015461662d41dcfb3bb95fadd8a2a42ad8eacf'
  - url: 'https://git.kernel.org/stable/c/6dc10494cfe27b6f1e9adb7e293293ae39c50b7c'
  - url: 'https://git.kernel.org/stable/c/d2c785733dfb853ea0b53984c75662a1af230a94'
  - url: 'https://git.kernel.org/stable/c/fdbccddb7e7822016601829f95de4008e193f7bc'
  - url: 'https://git.kernel.org/stable/c/c3659273860bed0c8e573b865e3769abc51225a8'
  - url: 'https://git.kernel.org/stable/c/6d2f142b1e4b203387a92519d9d2e34752a79dbb'
tags:
  - cve.org
epss: 0.0013
epssPercentile: 0.02626
ingestedAt: '2026-11-06T16:57:43.390Z'
---

## Overview

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

net: hns3: fix double free issue for tx spare buffer

In hns3_set_ringparam(), a temporary copy (tmp_rings) of the ring structure
is created for rollback. However, the tx_spare pointer in the original
ring handle is incorrectly left pointing to the old backup memory.

Later, if memory allocation fails in hns3_init_all_ring() during the setup,
the error path attempts to free all newly allocated rings. Since tx_spare
contains a stale (non-NULL) pointer from the backup, it is mistaken for
a newly allocated buffer and is erroneously freed, leading to a double-free
of the backup memory.

The root cause is that the tx_spare field was not cleared after its value
was saved in tmp_rings, leaving a dangling pointer.

Fix this by setting tx_spare to NULL in the original ring structure
when the creation of the new `tx_spare` fails. This ensures the
error cleanup path only frees genuinely newly allocated buffers.

## Affected

- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < fb6a4c376d454b425555b1b0bda36e99f56ec307`
- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < 43015461662d41dcfb3bb95fadd8a2a42ad8eacf`
- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < 6dc10494cfe27b6f1e9adb7e293293ae39c50b7c`
- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < d2c785733dfb853ea0b53984c75662a1af230a94`
- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < fdbccddb7e7822016601829f95de4008e193f7bc`
- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < c3659273860bed0c8e573b865e3769abc51225a8`
- `Linux >= 907676b130711fd1f627824559e92259db2061d1 < 6d2f142b1e4b203387a92519d9d2e34752a79dbb`
- `Linux 5.14`

## Remediation

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