CVE-2023-52864

About vulnerability

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.

Affected product:

AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , CloudLinux 7 ELS , Debian 10 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

kernel @ 2.6.32 (+18 more)

Live-patch status from KernelCare for each operating system.