Nirjhar Roy — Software Engineer

I pursued masters (MS) from IIT Kanpur and presently working as a Linux Kernel Developer in IBM Lab's Linux Technology Center(LTC) focussing on linux's XFS filesystem and a little bit in memory management subsystem. My contributions list Core-kernel - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=author&q=Nirjhar+Roy xfstests - https://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git/log/?qt=author&q=Nirjhar+Roy Prior to this, I was working in a fast growing startup named, Fortanix Inc where my work mostly focuses on EnclaveOS, which is a linux like library operating system. I implement (and fix bugs) missing linux like system calls and system level nodes(like /proc/cpuinfo) in enclaveos. Along with that I have added support for various real life customer demanding applciation like Tensorflow Model Benchmarking, Openvino, Freeradius etc. I also spend sometime on attending calls with our parnters like Intel where I synch with them and try to enable various AI related applications. My work at IIT Kanpur also involved extensive research and development on secure demand paging schemes for enclave platforms like Keystone and Intel SGX. Most of the implementations were in C and C++ and a bit of RISC-V/x86 assembly. We used python to develop simulators for tuning various page replacement and ORAM parameters. Along with that we broke an existing state-of-the-art demand paging proposal and crafted a couple of new attacks. We had a publication accepted at one of the flagship workshops named WOOT'20 at USENIX. I am mostly interested to work in areas of computer systems like operating systems, computer architecture and/or computer security. I have also achieved a decent percentile of 99.65 (AIR 377) in GATE, a percentile of 97.6 in WBJEE and above 90% in my high school board examinations. Please browse through my linkedin profile to see what I have on the desk.

Stackforce AI infers this person is a Backend-heavy Infrastructure Engineer with expertise in Operating Systems and Cloud Computing.

Location: Bengaluru, Karnataka, India

Experience: 6 yrs 10 mos

Skills

Linux Kernel
File Systems
Operating Systems
Computer Security

Career Highlights

Contributed to core Linux kernel and XFS filesystem.
Implemented system calls in EnclaveOS for AI applications.
Published research on secure demand paging at USENIX.

Work Experience

IBM

Linux Kernel Developer (1 yr 7 mos)

Fortanix

Software Engineer 3 (2 yrs 1 mo)

Software Engineer 2 (1 yr 8 mos)

Indian Institute of Technology, Kanpur

Student Research Assistant (1 yr 6 mos)

Education

Master of Science - MS at Indian Institute of Technology, Kanpur

Bachelor of Technology - BTech at Institute Of Engineering and Management

Science with Computers at Calcutta Boys' School

Nirjhar Roy

Software Engineer

Bengaluru, Karnataka, India6 yrs 10 mos experience

AI ML PractitionerAI Enabled

Key Highlights

Contributed to core Linux kernel and XFS filesystem.
Implemented system calls in EnclaveOS for AI applications.
Published research on secure demand paging at USENIX.

Stackforce AI infers this person is a Backend-heavy Infrastructure Engineer with expertise in Operating Systems and Cloud Computing.

Contact

Skills

Core Skills

Linux KernelFile SystemsOperating SystemsComputer Security

Other Skills

AI ApplicationsAlgorithmsCC++CryptographyDebuggingEnclaveOSGitLinux System CallsMachine Learning (Basics)Memory ManagementOpenvinoPerformance OptimizationPythonResearch

About

Experience

Ibm

Linux Kernel Developer

Aug 2024 – Present · 1 yr 7 mos · Bengaluru, Karnataka, India · Hybrid

Working on core linux kernel focussing on file system and memory management subsystem.
My contributions list
Core-kernel - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=author&q=Nirjhar+Roy
xfstests - https://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git/log/?qt=author&q=Nirjhar+Roy

Linux KernelFile SystemsMemory Management

Fortanix

2 roles

Software Engineer 3

Promoted

Jul 2022 – Aug 2024 · 2 yrs 1 mo · Bengaluru, Karnataka, India · Remote

∙ Syscall implementations and bug fixes in linux like system calls
and system level nodes like /proc/cpuinfo in EnclaveOS - a linux
like library operating system.
∙ Interacting with our partners like Intel, attending weekly calls
and coordinating with them to enable various AI applications.
∙ Increased the performance of multithreaded ML applications
with 64+ cores by intelligently reducing lock contentions
∙ Implemented certain symlinks features in our EnclaveOS and
support for larger sized files (4G+)
∙ Collaborated with solutions team during customers’ Proof-Of-
Concepts(POCs)
∙ Conducted code reviews, regular code documentation and
mentorship to new joiners for a smooth on boarding.
∙ Adding support for applications like Tensorflow and openvino
models benchmarking, by analysing application logs and our
strace like EnclaveOS logs to figure out application behavior and
providing necessary bug fixes and performance optimizations.
∙ Familiarity with x86 architecture and basics of virtualization,
VM internals, KVM-qemu
∙ Familiarity with basic CPU internals like pipelining, hyperthread-
ing caching

EnclaveOSLinux System CallsAI ApplicationsPerformance OptimizationOperating SystemsLinux Kernel

Software Engineer 2

Jul 2020 – Mar 2022 · 1 yr 8 mos · Bengaluru, Karnataka, India · Remote

∙ Writing single threaded, multithreaded and multiprocess unit
tests for testing various linux like syscalls and system level
nodes implemented or bug fixed.
∙ Application debugging inside our platform using gdb.
∙ Fixed bugs and introduced timeouts and waits in SGX device
drivers to prevent unwanted application launch failures.
∙ Adding support for SGX2.0 features for newer kernel versions
(like kernel 6.0)
∙ Implementing support for newer instruction sets like Intel AMX
for upcoming newer generation of Intel CPUs like Sapphire
Rapids
∙ Fixing various security bugs that prevented attacks like MCDT
attack, AEPIC leak, unchecked pointer overflow bugs

Unit TestingDebuggingSecurity Bug FixesOperating SystemsLinux Kernel

Indian institute of technology, kanpur

Student Research Assistant

Jan 2019 – Jul 2020 · 1 yr 6 mos · Kānpur Area, India

Advisor: Dr. Pramod Subramanyan, IIT Kanpur
Aim: My research has focused on preventing information leakage via page faults in enclave platforms using Oblivious RAMs (ORAMs).
Research Overview: My research work has introduced new attacks and defences on demand paging in enclave platforms. On the
offensive side, my work shows that the current state-of-the-art for demand paging in enclaves (InvisiPage, ISCA’19) leaks some statistics and these can be used to exfiltrate secrets from enclave applications. On the defensive side, I have developed new algorithms
based on the Ring ORAM cryptographic primitive to enable performant and secure demand paging in the runtime for the Keystone
enclave platform. Our works shows it is possible to be more secure and more performant than the current state-of-the-art, InvisiPage.
Our implementation has been tested and evaluated on a commercially-available RISC-V board (HiFive Unleashed) and can be used to
run unmodified Linux-based Keystone enclave applications on this hardware.

ResearchCryptographyAlgorithmsComputer SecurityOperating Systems