Linux Kernel ICSS IEP Driver NULL Pointer Dereference Vulnerability

A NULL pointer dereference vulnerability has been identified in the ICSS IEP driver of the Linux kernel. This issue arises when disabling PPS and perout signals during the 'icss_iep_exit()' function, leading to a NULL pointer dereference for the perout request. The vulnerability can be addressed by modifying the 'icss_iep_perout_enable_hw' function to directly clear the IEP CMP registers when disabling PPS or PEROUT, without referencing the 'ptp_perout_request' structure, as its contents are not relevant in this context.

Impact

Exploitation of this vulnerability leads to a NULL pointer dereference, causing a crash or undefined behavior in the kernel.