nelhage

/* gcc -o nostdlib nostdlib.c -m32 -z execstack -nostdlib */
/* Who needs libc or asm() when you can abuse the ABI in horrible ways?*/
typedef int (*sc_fun)(int,int,int,int,int,int,int);

void _start(void) {
    char syscall[] = "\x60\x83\xc4\x24\x58\x5b\x59\x5a\x5e\x5f\x5d\xcd\x80\x83\xec\x40\x61\xc3";

    ((sc_fun)syscall)(4, 0, "Hello, World\n", 13, 0, 0, 0);
    ((sc_fun)syscall)(1, 0, 0, 0, 0, 0, 0);
}

nelhage

commit 6297e8bbfa2ef9b870a182c29a26f189297b4b63
Author: Nelson Elhage <nelhage@ksplice.com>
Date:   Tue Oct 5 10:57:58 2010 -0400

    Don't use a pager when called through M-x grep.

diff --git a/pager.c b/pager.c
index dac358f..32ff2f3 100644
--- a/pager.c
+++ b/pager.c

nelhage

Hi pdos,


For tomorrow's group meeting, I will be giving a talk on a survey of
linux kernel vulnerabilities.

The talk will present data on 141 Linux kernel vulnerabilities discovered in
the past 15 months, and examine how well state-of-the-art techniques
address these real bugs. The main findings are that no techniques are
fully effective, and that semantic bugs---violations of high-level security

nelhage

#include <stdio.h>
#include <stdlib.h>

struct hentry {
    int foo;
    char word[1];
};

int main(void) {
    struct hentry h, *h1 = &h, *h2 = (struct hentry*)malloc(sizeof(struct hentry) - 1 + 10);

nelhage

{-
Copyright (c) 2011 Nelson Elhage
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright

nelhage

class smart_object_base {
public:
    smart_object_base() : obj_(0) {
    };

    operator git_object** () {
        return &obj_;
    }

nelhage

#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <stdint.h>
#include <string.h>

nelhage

fluid-let

nelhage

#include <stdlib.h>
#include <stdio.h>

#define NALLOC		(1 << 10)
#define ALLOCSZ		(1 << 12)

int main(void) {
	void *buffers[NALLOC];
	int i;

nelhage

#include <stdlib.h>
#include <stdio.h>

struct doit_kwargs {
    int a, b, c;
};

void __doit(struct doit_kwargs kw) {
    printf("%d %d %d\n", kw.a, kw.b, kw.c);
}