CVE-2022-49968

Technical Description

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

ieee802154/adf7242: defer destroy_workqueue call

There is a possible race condition (use-after-free) like below

(FREE) | (USE)

adf7242_remove | adf7242_channel

cancel_delayed_work_sync |

destroy_workqueue (1) | adf7242_cmd_rx

| mod_delayed_work (2)

|

The root cause for this race is that the upper layer (ieee802154) is

unaware of this detaching event and the function adf7242_channel can

be called without any checks.

To fix this, we can add a flag write at the beginning of adf7242_remove

and add flag check in adf7242_channel. Or we can just defer the

destructive operation like other commit 3e0588c291d6 ("hamradio: defer

ax25 kfree after unregister_netdev") which let the

ieee802154_unregister_hw() to handle the synchronization. This patch

takes the second option.

runs")

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