Linux Kernel Monitor Mode WARN_ON Vulnerability in mac80211 WiFi Handling

A vulnerability in the Linux kernel's mac80211 WiFi handling has been addressed. The issue involved a WARN_ON warning for monitor interfaces on devices lacking WANT_MONITOR_VIF support, and likely without channel context support. This warning arose when attempting to change per-link settings for a monitor interface. The vulnerability has been resolved by modifying the link change code to handle these cases appropriately, rather than issuing a warning. The fix is applicable to the Linux kernel stable tree.

Impact

The vulnerability could lead to improper handling of monitor mode interfaces in the mac80211 WiFi subsystem, potentially causing issues with link management and transmission power control.

Reproduction

The vulnerability can be reproduced on Linux devices that do not have WANT_MONITOR_VIF support and probably lack channel context support. When a monitor interface is active, the system will issue a WARN_ON warning if an attempt is made to change the per-link settings. This behavior can be observed by monitoring the system logs while performing actions that trigger the link change notifications for monitor mode interfaces.

Remediation

Users can apply the latest updates from the Linux kernel stable tree to address this vulnerability.