Experimental Analysis of FreeRTOS Dependability through Targeted Fault Injection Campaigns

TL;DR

This paper introduces KRONOS, a software-based fault injection framework, to evaluate FreeRTOS dependability under radiation-induced faults, revealing how kernel data corruption affects system stability.

Contribution

The paper presents KRONOS, a novel non-intrusive fault injection tool for FreeRTOS, enabling detailed analysis of kernel data corruption impacts without specialized hardware.

Findings

Pointer and scheduler variable corruptions often cause system crashes.

Many TCB field corruptions have limited impact on availability.

KRONOS effectively characterizes FreeRTOS dependability under fault conditions.

Abstract

Real-Time Operating Systems (RTOSes) play a crucial role in safety-critical domains, where deterministic and predictable task execution is essential. Yet they are increasingly exposed to ionizing radiation, which can compromise system dependability. To assess FreeRTOS under such conditions, we introduce KRONOS, a software-based, non-intrusive post-propagation Fault Injection (FI) framework that injects transient and permanent faults into Operating System-visible kernel data structures without specialized hardware or debug interfaces. Using KRONOS, we conduct an extensive FI campaign on core FreeRTOS kernel components, including scheduler-related variables and Task Control Blocks (TCBs), characterizing the impact of kernel-level corruptions on functional correctness, timing behavior, and availability. The results show that corruption of pointer and key scheduler-related variables frequently leads to crashes, whereas many TCB fields have only a limited impact on system availability.