CVE-2021-47587

Technical Description

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

net: systemport: Add global locking for descriptor lifecycle

The descriptor list is a shared resource across all of the transmit queues, and

the locking mechanism used today only protects concurrency across a given

transmit queue between the transmit and reclaiming. This creates an opportunity

for the SYSTEMPORT hardware to work on corrupted descriptors if we have

multiple producers at once which is the case when using multiple transmit

queues.

This was particularly noticeable when using multiple flows/transmit queues and

it showed up in interesting ways in that UDP packets would get a correct UDP

header checksum being calculated over an incorrect packet length. Similarly TCP

packets would get an equally correct checksum computed by the hardware over an

incorrect packet length.

The SYSTEMPORT hardware maintains an internal descriptor list that it re-arranges

when the driver produces a new descriptor anytime it writ

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. 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.

Affected Products

References