Brendan Dolan-Gavitt moyix

Assistant Professor in CSE at NYU Tandon School of Engineering, focusing on security, program analysis, and reverse engineering.

moyix / shadowstack.c

Last active March 23, 2022 17:43

Example of using a constructor to set up the shadow callstack and assign gs appropriately

	#include <stdio.h>
	#include <asm/prctl.h>
	#include <sys/prctl.h>
	#include <stdlib.h>

	// Compile with: clang-8 -fsanitize=shadow-call-stack shadowstack.c -o shadowstack

	int arch_prctl(int code, unsigned long *addr);

	void __attribute__ ((constructor)) __attribute__((no_sanitize("shadow-call-stack"))) setupgs()

moyix / tiffcrop.c

Created March 22, 2022 19:58

Buggy code from libtiff

	static int readSeparateTilesIntoBuffer (TIFF* in, uint8 *obuf,
	uint32 imagelength, uint32 imagewidth,
	uint32 tw, uint32 tl,
	uint16 spp, uint16 bps)
	{
	int i, status = 1, sample;
	int shift_width, bytes_per_pixel;
	uint16 bytes_per_sample;
	uint32 row, col; /* Current row and col of image */
	uint32 nrow, ncol; /* Number of rows and cols in current tile */

moyix / codex_commands.txt

Created March 11, 2022 16:18

Commands executed by Codex across 100 five-minute runs in a Linux VM

moyix / async_lsremote.py

Last active July 20, 2022 17:42

Retrieve reflist for a repository on Github using httpx and asyncio

moyix / getrepo.sh

Created February 18, 2022 02:53

Geez this is awful

	#!/bin/bash

	DB_TIMEOUT=10000

	if [[ $# -ne 3 ]]; then
	echo "getrepo.sh name url jobslot"
	exit 1
	fi

	jobslot="$3"

moyix / gcasm.py

Created February 15, 2022 01:21

Assembler and demo program for the (made-up) THX-1138 CPU used by the gift card reader in NYU's Application Security Course

	#!/usr/bin/env python3

	# An assembler for the THX-1138 CPU used in NYU AppSec's gift card reader.
	# From giftcard.h:
	# programs operate on the message buffer
	# note!! it is the gift card producers job to make sure that
	# programs in the gift card are VALID
	# each "instruction" is 3 bytes
	# arithmetic instructions set the zero flag if the result is 0
	# opcode (1 byte) arg1 (1 byte) arg2 (1 byte)

moyix / sample_output_t0.0_p0.0.csv

Created February 13, 2022 23:31

GPT-NeoX-20B arithmetic, raw data for a parameter sweep over temperature and top-p

moyix / magnitude.csv

Created February 13, 2022 03:42

GPT-NeoX-20B arithmetic at different orders of magnitude (raw data)

We can't make this file beautiful and searchable because it's too large.

	question,a,op,b,real,guess,correct,digits_correct,ends_correct,rel_error,norm_edit
	What is 4 + 2?,4,+,2,6,6,Yes,1,2,0.0,1.0
	What is 7 + 9?,7,+,9,16,16,Yes,2,2,0.0,1.0
	What is 9 + 9?,9,+,9,18,18,Yes,2,2,0.0,1.0
	What is 8 + 6?,8,+,6,14,14,Yes,2,2,0.0,1.0
	What is 1 + 8?,1,+,8,9,9,Yes,1,2,0.0,1.0
	What is 5 + 5?,5,+,5,10,10,Yes,2,2,0.0,1.0
	What is 4 + 3?,4,+,3,7,7,Yes,1,2,0.0,1.0
	What is 5 + 5?,5,+,5,10,10,Yes,2,2,0.0,1.0
	What is 1 + 5?,1,+,5,6,6,Yes,1,2,0.0,1.0

moyix / arith1000_t0.1_k0_p0.0_results.txt

Created February 10, 2022 21:52

Data files for GPT-NeoX-20B arithmetic (100 and 1000 questions)

	Question Real Guess Correct? RelErr Digits
	What is 18857 - 592? 18265 18265 Yes 0.0% 5/5
	What is 30752 - 3087? 27665 27365 No 1.1% 4/5
	What is 2241 + 19873? 22114 22114 Yes 0.0% 5/5
	What is 5412 + 10169? 15581 15581 Yes 0.0% 5/5
	What is 11831 - 9178? 2653 3153 No 18.8% 2/4
	What is 1701 * 19933? 33906033 33953373 No 0.1% 4/8
	What is 11648 + 17851? 29499 30509 No 3.4% 1/5
	What is 29253 - 6202? 23051 22151 No 3.9% 3/5
	What is 27365 + 24989? 52354 53554 No 2.3% 3/5

moyix / neox_20B_math.txt

Created February 10, 2022 16:16

Results of asking GPT-NeoX-20B some math questions