Vulnerability in Kernel: cfg80211_stop_ap not called when switching from P2P_GO type

Background

The Kernel is a critical component of the Linux operating system that provides core functionalities and interfaces with hardware devices. It manages system resources, facilitates communication between software and hardware, and ensures the stability and security of the system. The cfg80211 module within the Kernel is responsible for handling wireless network configuration and management. It provides APIs for various wireless operations, including creating and stopping access points (APs) in P2P_GO mode.

Vulnerability Detail

The vulnerability identified in the Kernel's cfg80211 module occurs when switching from P2P_GO mode to another mode. In this scenario, the cfg80211_stop_ap function, which is responsible for stopping the AP, is not called. This oversight can lead to unintended consequences, such as the AP remaining active and accessible even when it should be terminated. Attackers could potentially exploit this vulnerability to gain unauthorized access to the network or perform other malicious activities.

Workaround

As a temporary workaround, users can manually call the cfg80211_stop_ap function when switching from P2P_GO mode. This can be achieved by executing the following code snippet:

#include <net/cfg80211.h>

void stop_ap_workaround()
{
    struct cfg80211_registered_device *rdev;
    // Get the registered device
    rdev = cfg80211_get_dev_by_name("<device_name>");
    if (rdev) {
        // Stop the AP
        cfg80211_stop_ap(rdev, <AP_interface>, <reason_code>);
        // Release the device
        cfg80211_put_dev(rdev);
    }
}

Replace <device_name> with the name of the wireless device and provide the appropriate values for <AP_interface> and <reason_code> based on your specific configuration.

Conclusion

The vulnerability in the Kernel's cfg80211 module, which fails to call cfg80211_stop_ap when switching from P2P_GO mode, can have serious security implications. It is crucial to update the Linux Kernel to version v5.15.5 or later to mitigate this vulnerability. In the meantime, a temporary workaround is available by manually invoking the cfg80211_stop_ap function. For further assistance or support in addressing this vulnerability, please contact DevNack.com.

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