CVE-2024-50220

/// Technical description

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

fork: do not invoke uffd on fork if error occurs

Patch series "fork: do not expose incomplete mm on fork".

During fork we may place the virtual memory address space into an

inconsistent state before the fork operation is complete.

In addition, we may encounter an error during the fork operation that

indicates that the virtual memory address space is invalidated.

As a result, we should not be exposing it in any way to external machinery

that might interact with the mm or VMAs, machinery that is not designed to

deal with incomplete state.

We specifically update the fork logic to defer khugepaged and ksm to the

end of the operation and only to be invoked if no error arose, and

disallow uffd from observing fork events should an error have occurred.

This patch (of 2):

Currently on fork we expose the virtual address space of a process to

userland unconditionally if uffd is registered in VMAs, regardless of

whether a

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References