You can patch Grid Infrastructure Management Repository by installing in-place or out-of-place patches using the OPatch utility.

• In-Place Grid Infrastructure Management Repository Patching
  Use this procedure on each cluster node to perform in-place patching of Grid Infrastructure Management Repository (GIMR).
• Out-of-Place Grid Infrastructure Management Repository Patching
  Use this procedure on each cluster node to perform out-of-place patching of Grid Infrastructure Management Repository (GIMR).
• In-Place Grid Infrastructure Management Repository Patch Rollback
  Use this procedure on each cluster node for in-place Grid Infrastructure Management Repository (GIMR) patch rollback, in case of a failure or an error.
• Out-of-Place Grid Infrastructure Management Repository Patch Rollback
  Use this procedure on each cluster node for out-of-place Grid Infrastructure Management Repository (GIMR) patch rollback, in case of a failure or an error.