Overview
KernelCare agent resides on user's server. It periodically checks in with KernelCare distribution servers. If there are new patches available for the currently running kernel, KernelCare agent downloads and applies those patches to the running kernel. A KernelCare patch is a piece of code used to substitute vulnerable or buggy code in a kernel. It can be an arbitrary code line modification, or it can be a missing security check, a set of functions, or even modified data structures. The patch is compiled as usual, but the generated code has additional information about all changed code pieces caused by original source code modification and information on to how to apply these code pieces. The resulting code modifications are safely applied to the running kernel. A special KernelCare kernel module applies the patches. It loads the patches into the kernel address space, sets up the relocations (i.e., fixes the references to the original kernel code and data), and safely switches the execution path from the original code to updated code blocks. The code ensures the patch is applied safely so theSee also
* Dynamic software updating, a field of research focusing on upgrading programs while they are running * kexec, a method for loading a whole new kernel from a running system * kGraft, kpatch and Ksplice, other Linux kernel live patching technologies developed by SUSE, Red Hat and Ksplice, Inc. (later acquired by Oracle), respectivelyReferences
External links
* {{Operating system Free security software programmed in C Linux kernel live patching Linux-only free software