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/* $OpenBSD: nxheap-mprotect.c,v 1.2 2002/08/27 16:43:51 matthieu Exp $ */
/*
* Copyright (c) 2002 Michael Shalayeff
* 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
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/mman.h>
#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <stdlib.h>
#define SIZE 256 /* assuming the testfly() will fit */
volatile sig_atomic_t fail;
void
testfly()
{
}
void
sigsegv(int sig)
{
_exit(fail);
}
int
main(void)
{
u_int64_t *buf;
buf = (u_int64_t *)malloc(SIZE);
signal(SIGSEGV, sigsegv);
memcpy(buf, &testfly, SIZE);
printf("making it execute\n");
/* here we must fail on segv since we said it gets executable */
fail = 1;
mprotect(buf, sizeof(buf), PROT_READ|PROT_WRITE|PROT_EXEC);
((void (*)(void))buf)();
printf("making it catch a signal\n");
/* here we are successfull on segv and fail if it still executes */
fail = 0;
mprotect(buf, sizeof(buf), PROT_READ|PROT_WRITE);
((void (*)(void))&buf)();
exit(1);
}
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