---
id: CVE-2026-90108
title: >-
  In the Linux kernel, the following vulnerability has been resolved:


  net/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK
  transition


  When smc_llc_event_handler() transitions the local LLC flow from

  SMC_LLC_FLOW_REQ_…
summary: >-
  In the Linux kernel, the following vulnerability has been resolved:


  net/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK
  transition


  When smc_llc_event_handler() transitions the local LLC flow from

  SMC_LLC_FLOW_REQ_…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196 <
    7dd55348c0d9399a9448847819e9f3904ae507ad
  - >-
    Linux >= b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196 <
    056395acb7041b3a1f2baa08d89a1938a8b8776a
  - >-
    Linux >= b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196 <
    b08aacfb226a840628151643b6a34eecf545d311
  - >-
    Linux >= b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196 <
    0fb9a513766071ea9d5f3bf988e39241b8e9ee3b
  - >-
    Linux >= b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196 <
    e25a602c45c76a7130878db72bcf6f76df04bf85
  - >-
    Linux >= b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196 <
    036322025d6e440cb75fc6fecbba9a16b271a2ae
  - Linux 5.16
published: '2026-09-17'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T17:17:02.730'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90108'
references:
  - url: 'https://git.kernel.org/stable/c/036322025d6e440cb75fc6fecbba9a16b271a2ae'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/056395acb7041b3a1f2baa08d89a1938a8b8776a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/0fb9a513766071ea9d5f3bf988e39241b8e9ee3b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7dd55348c0d9399a9448847819e9f3904ae507ad'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b08aacfb226a840628151643b6a34eecf545d311'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e25a602c45c76a7130878db72bcf6f76df04bf85'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-17T16:21:47.887Z'
epss: 0.00205
epssPercentile: 0.10897
---

## Overview

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

net/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK transition

When smc_llc_event_handler() transitions the local LLC flow from
SMC_LLC_FLOW_REQ_ADD_LINK to SMC_LLC_FLOW_ADD_LINK on arrival of an ADD_LINK
request, it calls smc_llc_flow_qentry_set() unconditionally:

	if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_REQ_ADD_LINK) {
		lgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;
		smc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);
		...
	}

A CONFIRM_LINK or ADD_LINK_CONT arriving while flow->type is
SMC_LLC_FLOW_REQ_ADD_LINK is stashed into flow->qentry via the
SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT handler (which stores into
flow->qentry for any non-NONE flow type).  When the subsequent ADD_LINK
arrives, the REQ_ADD_LINK branch overwrites flow->qentry with the new pointer
without first freeing the stashed allocation, leaking one kmalloc object.

The stashed entry has no consumer: smc_llc_wait() is only called from
llc_add_link_work, which is not yet scheduled while the flow type remains
REQ_ADD_LINK.  No waiter is sleeping on llc_msg_waiter at this point.
It is safe to unconditionally free any stashed qentry before
the overwrite.

Call smc_llc_flow_qentry_del() before smc_llc_flow_qentry_set() in the
REQ_ADD_LINK branch.  smc_llc_flow_qentry_del() already checks flow->qentry
before freeing, so the normal path where no entry is stashed is a no-op.

## Remediation

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