Uncovering RowHammer: Memory Vulnerabilities and Solutions with Prof. Onur Mutlu
We will examine the RowHammer problem in Dynamic Random Access Memory
(DRAM), the first example of how a circuit-level failure mechanism can
cause a practical and widespread system security vulnerability. RowHammer
is the phenomenon that repeatedly accessing a row in a modern DRAM chip
predictably causes bitflips in physically-adjacent rows. Building on our
initial fundamental work that appeared at ISCA 2014, Google Project Zero
demonstrated that this hardware phenomenon can be exploited by user-level
programs to gain kernel privileges. Many other works demonstrated other
attacks exploiting RowHammer, including remote takeover of a server
vulnerable to RowHammer, takeover of a mobile device by a malicious
user-level application, and destruction of predictive capabilities of
commonly-used deep neural networks.
Unfortunately, the RowHammer problem still plagues cutting-edge DRAM chips,
DDR4 and beyond. Based on our recent characterization studies of more than
1500 DRAM chips from six technology generations that appeared at ISCA 2020
and MICRO 2021, we show that RowHammer at the circuit level is getting much
worse, newer DRAM chips are much more vulnerable to RowHammer than older
ones, and existing mitigation techniques do not work well. We also show
that existing proprietary mitigation techniques employed in DDR4 DRAM
chips, which are advertised to be Rowhammer-free, can be bypassed via
many-sided hammering (also known as TRRespass & Uncovering TRR).
In this talk, we will provide an overview of RowHammer research in academia
and industry, with a special focus on recent works that rigorously analyze
real chip characteristics and introduce promising solution ideas. We will
discuss the effect of RowHammer on High-Bandwidth Memory (HBM) chips and
introduce and analyze RowPress, which is a fundamentally different read
disturbance phenomenon that also affects all DRAM chips. RowPress greatly
(e.g., by 100X) reduces the activation count required to induce bitflips,
by keeping an activated row open for a long time. We will also discuss what
other problems may be lurking in DRAM and other types of memory, which can
potentially threaten the foundations of reliable and secure systems, as
memory technologies scale to higher densities. We will conclude by
describing and advocating a principled approach to memory robustness
(including reliability, security, safety) research that can enable us to
better anticipate and prevent such vulnerabilities.
A short accompanying paper, which appeared at ASP-DAC 2023, can be found
here and serves as recommended reading:
“Fundamentally Understanding and Solving RowHammer”
https://arxiv.org/abs/2211.
Onur Mutlu
Professor, Computer Science at ETH Zurich on February 16, 2024 at 10:15 AM in EB2 1231
Onur Mutlu is a Professor of Computer Science at ETH Zurich. He is also a
Visiting Professor at Stanford University and a faculty member at Carnegie
Mellon University, where he previously held the Strecker Early Career
Professorship. His current broader research interests are in computer
architecture, systems, hardware security, and bioinformatics. A variety of
techniques he, along with his group and collaborators, has invented over
the years have influenced industry and have been employed in commercial
microprocessors and memory/storage systems. He obtained his PhD and MS in
ECE from the University of Texas at Austin and BS degrees in Computer
Engineering and Psychology from the University of Michigan, Ann Arbor. He
started the Computer Architecture Group at Microsoft Research (2006-2009),
and held various product and research positions at Intel Corporation,
Advanced Micro Devices, VMware, and Google. He received various honors for
his research, including the Persistent Impact Prize of the Non-Volatile
Memory Systems Workshop, Intel Outstanding Researcher Award, IEEE High
Performance Computer Architecture Test of Time Award, IEEE Computer Society
Edward J. McCluskey Technical Achievement Award, ACM SIGARCH Maurice Wilkes
Award and a healthy number of best paper or “Top Pick” paper recognitions
at various computer systems, architecture, and security venues. He is an
ACM Fellow, IEEE Fellow, and an elected member of the Academy of Europe.
His computer architecture and digital logic design course lectures and
materials are freely available on YouTube (
https://www.youtube.com/OnurMutluLectures), and his research group makes a
wide variety of software and hardware artifacts freely available online (
https://safari.ethz.ch/). For more information, please see his webpage at
https://people.inf.ethz.ch/omutlu/.
This lecture series features exciting and dynamic visiting and virtual speakers from across the range of ECE disciplines. Take some time every Friday morning to be inspired by these great scientists and engineers before heading into the weekend!