---
id: CVE-2026-72339
title: 'qede: fix off-by-one in BD ring consumption on build_skb failure'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  qede: fix off-by-one in BD ring consumption on build_skb failure

  qede_rx_build_skb() and qede_tpa_rx_build_skb() do not check for a
  NULL return from qede_build_skb(). …
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    ecc05d4b20220a09c9c69584fc46ca55248a374a
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    07be8b8adf91b7ada4c3dacce064d572a6066421
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    1624aa100c0b218181aa74e3696a389b509298cb
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    0bf78df2d3ecb1f4964ff42a7327d25845955153
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    814a5edac8c9fc04051808d5faaa93768e989281
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    b066420e57f3402a52c998678b4678252ac9bb63
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    982d6d6bc059c5dff37a2201c2f08c14bcfcbd20
  - >-
    Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e <
    a0a558ca7e75b49e71f8c545c30e8c005e6e4e2f
  - Linux 4.18
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T18:47:21.272710Z'
published: '2026-08-15'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T18:55:18.961Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-72339'
references:
  - url: 'https://git.kernel.org/stable/c/ecc05d4b20220a09c9c69584fc46ca55248a374a'
  - url: 'https://git.kernel.org/stable/c/07be8b8adf91b7ada4c3dacce064d572a6066421'
  - url: 'https://git.kernel.org/stable/c/1624aa100c0b218181aa74e3696a389b509298cb'
  - url: 'https://git.kernel.org/stable/c/0bf78df2d3ecb1f4964ff42a7327d25845955153'
  - url: 'https://git.kernel.org/stable/c/814a5edac8c9fc04051808d5faaa93768e989281'
  - url: 'https://git.kernel.org/stable/c/b066420e57f3402a52c998678b4678252ac9bb63'
  - url: 'https://git.kernel.org/stable/c/982d6d6bc059c5dff37a2201c2f08c14bcfcbd20'
  - url: 'https://git.kernel.org/stable/c/a0a558ca7e75b49e71f8c545c30e8c005e6e4e2f'
tags:
  - cve.org
epss: 0.00745
epssPercentile: 0.53884
ingestedAt: '2026-10-16T19:46:24.405Z'
---

## Overview

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

qede: fix off-by-one in BD ring consumption on build_skb failure

qede_rx_build_skb() and qede_tpa_rx_build_skb() do not check for a
NULL return from qede_build_skb(). When it returns NULL under memory
pressure, the functions still consume a BD from the ring before
returning NULL. The callers then recycle additional BDs, resulting in
one extra BD being consumed (off-by-one). This desynchronizes the BD
ring, which can corrupt DMA page reference counts and lead to SLUB
freelist corruption.

Commit 4e910dbe3650 ("qede: confirm skb is allocated before using")
added a NULL check inside qede_build_skb() to prevent a NULL pointer
dereference, but did not address the missing NULL checks in the
callers, making this off-by-one reachable.

Fix this by adding NULL checks for the return value of
qede_build_skb() in both qede_rx_build_skb() and
qede_tpa_rx_build_skb(), returning NULL immediately before any BD ring
manipulation.

## Affected

- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < ecc05d4b20220a09c9c69584fc46ca55248a374a`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < 07be8b8adf91b7ada4c3dacce064d572a6066421`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < 1624aa100c0b218181aa74e3696a389b509298cb`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < 0bf78df2d3ecb1f4964ff42a7327d25845955153`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < 814a5edac8c9fc04051808d5faaa93768e989281`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < b066420e57f3402a52c998678b4678252ac9bb63`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < 982d6d6bc059c5dff37a2201c2f08c14bcfcbd20`
- `Linux >= 8a8633978b842c88fbcfe00d4e5dde96048f630e < a0a558ca7e75b49e71f8c545c30e8c005e6e4e2f`
- `Linux 4.18`

## Remediation

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