CVE-2023-52864

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

platform/x86: wmi: Fix opening of char device

Since commit fa1f68db6ca7 ("drivers: misc: pass miscdevice pointer via file private data"), the miscdevice stores a pointer to itself inside filp->private_data, which means that private_data will not be NULL when wmi_char_open() is called. This might cause memory corruption should wmi_char_open() be unable to find its driver, something which can happen when the associated WMI device is deleted in wmi_free_devices().

Fix the problem by using the miscdevice pointer to retrieve the WMI device data associated with a char device using container_of(). This also avoids wmi_char_open() picking a wrong WMI device bound to a driver with the same name as the original driver.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.