Linux Kernel Memory Leak Vulnerability in x86/MCE/AMD Component

A memory leak vulnerability has been identified in the Linux kernel within the x86/MCE/AMD component. This issue arises in the 'mce_threshold_create_device()' function when 'threshold_create_bank()' fails. The failure prevents the proper deallocation of a previously allocated array, leading to a memory leak. The problem occurs because the cleanup function 'mce_threshold_remove_device()' can only access the pointer through a per-CPU variable after a bank has been successfully created. To address this, a new helper function has been added to properly unwind the bank creation process and free the allocated resources.

Impact

Exploitation of this vulnerability leads to a memory leak, where allocated memory is not properly released, potentially causing increased memory usage and degradation of system performance over time.