#!/bin/sh # # Copyright (c) 2014 EMC Corp. # 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. # # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 CONTRIBUTORS 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 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. # # Test scenario by kib@ [ `uname -m` = "i386" ] || exit 0 . ../default.cfg grep -q MAP_GUARD /usr/include/sys/mman.h 2>/dev/null || exit 0 here=`pwd` cd /tmp sed '1,/^EOF/d' < $here/$0 > mmap16.c mycc -o mmap16 -Wall -Wextra -O2 -g mmap16.c -lpthread || exit 1 rm -f mmap16.c /tmp/mmap16.core echo "Expect: mmap16: mprotect: Permission denied" /tmp/mmap16 > /dev/null s=$? rm -f /tmp/mmap16 /tmp/mmap16.core exit $s EOF /* $Id: map_hole.c,v 1.6 2014/06/16 05:52:03 kostik Exp kostik $ */ #include #include #include #include #include #include #include #include #include #include #include static void sighandler(int signo, siginfo_t *info, void *uap1) { static char scratch; ucontext_t *uap; uap = uap1; printf("SIG%s(%d) at %p (%%eax %p)\n", signo < sys_nsig ? sys_signame[signo] : "SOME", signo, info->si_addr, (void *)(uintptr_t)uap->uc_mcontext.mc_eax); uap->uc_mcontext.mc_eax = (uintptr_t)&scratch; } static void access_addr(char *addr) { char r; r = '1'; printf("accessing %p\n", addr); __asm __volatile("movb %0,(%%eax)" : : "i"(r), "a"(addr) : "memory"); printf("done\n"); } static int pagesz; static void test_access(char *addr) { struct rusage ru; long majflt, minflt; if (getrusage(RUSAGE_THREAD, &ru) == -1) err(1, "getrusage"); majflt = ru.ru_majflt; minflt = ru.ru_minflt; access_addr(addr); if (mprotect(addr, pagesz, PROT_READ | PROT_WRITE) == -1) warn("mprotect"); access_addr(addr); if (getrusage(RUSAGE_THREAD, &ru) == -1) err(1, "getrusage"); majflt = ru.ru_majflt - majflt; minflt = ru.ru_minflt - minflt; printf("majflt %ld minflt %ld\n", majflt, minflt); } int main(void) { struct sigaction sa; char *addr; char cmd[128]; bzero(&sa, sizeof(sa)); sa.sa_sigaction = sighandler; sa.sa_flags = SA_SIGINFO; if (sigaction(SIGSEGV, &sa, NULL) == -1) err(1, "sigaction"); pagesz = getpagesize(); printf("MAP_GUARD\n"); addr = mmap(NULL, pagesz, PROT_NONE, MAP_GUARD, -1, 0); if (addr == (char *)MAP_FAILED) err(1, "FAIL: mmap(MAP_GUARD)"); test_access(addr); printf("PROT_NONE wire\n"); addr = mmap(NULL, pagesz, PROT_NONE, MAP_ANON, -1, 0); if (addr == (char *)MAP_FAILED) err(1, "mmap(PROT_NONE)"); if (mlock(addr, pagesz) == -1) if (errno != ENOMEM) err(1, "mlock"); test_access(addr); snprintf(cmd, sizeof(cmd), "procstat -v %d", getpid()); system(cmd); return (0); }