CVE-2026-23463 soc: fsl: qbman: fix race condition in qman_destroy_fq

Medium 4.7 Published 3 Apr 2026 Updated 15 Oct 2026

A race condition in the Linux kernel's FSL QBMAN driver can trigger a kernel warning and potential denial of service during frame queue destruction.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-23463?

CVE-2026-23463 is a medium-severity vulnerability in Linux kernel, published on 3 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

soc: fsl: qbman: fix race condition in qman_destroy_fq

When QMAN_FQ_FLAG_DYNAMIC_FQID is set, there's a race condition between fq_table[fq->idx] state and freeing/allocating from the pool and WARN_ON(fq_table[fq->idx]) in qman_create_fq() gets triggered.

Indeed, we can have: Thread A Thread B qman_destroy_fq() qman_create_fq() qman_release_fqid() qman_shutdown_fq() gen_pool_free() -- At this point, the fqid is available again -- qman_alloc_fqid() -- so, we can get the just-freed fqid in thread B -- fq->fqid = fqid; fq->idx = fqid * 2; WARN_ON(fq_table[fq->idx]); fq_table[fq->idx] = fq; fq_table[fq->idx] = NULL;

And adding some logs between qman_release_fqid() and fq_table[fq->idx] = NULL makes the WARN_ON() trigger a lot more.

To prevent that, ensure that fq_table[fq->idx] is set to NULL before gen_pool_free() is called by using smp_wmb().

Weakness: CWE-362

Which versions are affected by CVE-2026-23463?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-23463?

Apply the vendor's patch.

Is CVE-2026-23463 being exploited?

There is no known exploitation of CVE-2026-23463 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as BELL-CVE-2026-23463, DEBIAN-CVE-2026-23463, GHSA-cxrg-39g8-v6cj, ROOT-OS-DEBIAN-11-CVE-2026-23463, ROOT-OS-DEBIAN-12-CVE-2026-23463, ROOT-OS-DEBIAN-13-CVE-2026-23463 and 3 more.