CVE-2022-48868

/// Technical description

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

dmaengine: idxd: Let probe fail when workqueue cannot be enabled

The workqueue is enabled when the appropriate driver is loaded and

disabled when the driver is removed. When the driver is removed it

assumes that the workqueue was enabled successfully and proceeds to

free allocations made during workqueue enabling.

Failure during workqueue enabling does not prevent the driver from

being loaded. This is because the error path within drv_enable_wq()

returns success unless a second failure is encountered

during the error path. By returning success it is possible to load

the driver even if the workqueue cannot be enabled and

allocations that do not exist are attempted to be freed during

driver remove.

Some examples of problematic flows:

(a)

idxd_dmaengine_drv_probe() -> drv_enable_wq() -> idxd_wq_request_irq():

In above flow, if idxd_wq_request_irq() fails then

idxd_wq_unmap_portal() is called on error exit path, bu

/// 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