ATF_TC_BODY(mprotect_pax, tc)
{
const int prot[4] = { PROT_NONE, PROT_READ, PROT_WRITE };
const char *str = NULL;
void *map;
size_t i;
int rv;
if (!paxinit() || !paxset(1, 1))
return;
/*
* As noted in the original PaX documentation [1],
* the following restrictions should apply:
*
* (1) creating executable anonymous mappings
*
* (2) creating executable/writable file mappings
*
* (3) making a non-executable mapping executable
*
* (4) making an executable/read-only file mapping
* writable except for performing relocations
* on an ET_DYN ELF file (non-PIC shared library)
*
* The following will test only the case (3).
*
* [1] http://pax.grsecurity.net/docs/mprotect.txt
*
* (Sun Apr 3 11:06:53 EEST 2011.)
*/
for (i = 0; i < __arraycount(prot); i++) {
map = mmap(NULL, page, prot[i], MAP_ANON, -1, 0);
if (map == MAP_FAILED)
continue;
rv = mprotect(map, 1, prot[i] | PROT_EXEC);
(void)munmap(map, page);
if (rv == 0) {
str = "non-executable mapping made executable";
goto out;
}
}
out:
if (pax_global != -1 && pax_enabled != -1)
(void)paxset(pax_global, pax_enabled);
if (str != NULL)
atf_tc_fail("%s", str);
}
static bool
paxinit(void)
{
size_t len = sizeof(int);
int rv;
rv = sysctlbyname("security.pax.mprotect.global",
&pax_global, &len, NULL, 0);
if (rv != 0)
return false;
rv = sysctlbyname("security.pax.mprotect.enabled",
&pax_enabled, &len, NULL, 0);
if (rv != 0)
return false;
return paxset(1, 1);
}