CVE-2022-49957 kcm: fix strp_init() order and cleanup

Medium 5.5 Published Updated

A logic error in the Linux kernel KCM module could lead to a null pointer dereference or lockdep warning, causing a denial of service.

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-2022-49957?

CVE-2022-49957 is a medium-severity vulnerability in Linux kernel, published on 18 Jun 2025. 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:

kcm: fix strp_init() order and cleanup

strp_init() is called just a few lines above this csk->sk_user_data check, it also initializes strp->work etc., therefore, it is unnecessary to call strp_done() to cancel the freshly initialized work.

And if sk_user_data is already used by KCM, psock->strp should not be touched, particularly strp->work state, so we need to move strp_init() after the csk->sk_user_data check.

This also makes a lockdep warning reported by syzbot go away.

Weakness: CWE-908

Which versions are affected by CVE-2022-49957?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-49957?

Apply the vendor's patch.

Is CVE-2022-49957 being exploited?

There is no known exploitation of CVE-2022-49957 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as DEBIAN-CVE-2022-49957, GHSA-cp59-hf68-p4rg, UBUNTU-CVE-2022-49957.

Is CVE-2022-49957 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free