Researchers at Washington State University have identified vulnerabilities in on-chip communications networks that can deliberately damage chips.
The researchers devised three attacks to test the network-on-a-chip (NoC) that connects cores. This additional workload enhanced electromigration-induced stress and crosstalk noise. The researchers found that a limited number of crucial vertical links of the communication system were particularly vulnerable to fail. Those links connect the processors in a stack and allows them to talk with each other, and the attacks were optimised to stress these links.
"We determined how an agent can target the communication system to start malfunctions in the chip," said Partha Pande, assistant professor in the School of Electrical Engineering and Computer Science. "The role of the communications and the threat had not been clear to the research community before. The communications system is the glue that holds everything together. "When it starts to malfunction, the whole system is going to crumble."
The team set up a security analysis framework by aging the NoC to study planned obsolescence by makers of manycore System-on-Chip (SoC) devices. Planned obsolescence may adopt any vulnerability in the NoC to cause the SoC to fail. The results showed how an OEM can craft workloads to generate electromigration-induced stress and crosstalk noise in through silicon vias (TSVs) in the NoC to hasten failure.
The three malicious workloads confirmed that a crafted workload that injects 3-10% more traffic on to a few selected critical vertical links can shorten the lifetime of the NoC by 11%-25% averaged over the benchmarks considered in this work.
The researchers will now be working to develop ways to mitigate the problem, such as automated techniques and algorithms to detect and thwart attacks.