Linux Kernel KASAN Use-After-Free Vulnerability in fsl-mc-bus Component

A use-after-free vulnerability has been identified in the Linux kernel's fsl-mc-bus component. The issue arises in the fsl_mc_bus_remove() function, where a reference to mc->root_mc_bus_dev->mc_io is passed to fsl_destroy_mc_io(). However, mc->root_mc_bus_dev is already freed in fsl_mc_device_remove(), leading to a use-after-free condition detected by KASAN. To prevent this, the reference should be stored in a local variable before being passed to fsl_destroy_mc_io(). This vulnerability affects Linux kernel versions prior to 5.15.

Impact

Exploitation of this vulnerability leads to a use-after-free condition, which can potentially be exploited to execute arbitrary code or cause a denial-of-service condition by crashing the system.