/* $NetBSD: t_x86_pte.c,v 1.2 2020/04/26 11:56:38 maxv Exp $ */
/*
* Copyright (c) 2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Maxime Villard.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
__COPYRIGHT("@(#) Copyright (c) 2020\
The NetBSD Foundation, inc. All rights reserved.");
__RCSID("$NetBSD: t_x86_pte.c,v 1.2 2020/04/26 11:56:38 maxv Exp $");
#include <sys/types.h>
#include <sys/module.h>
#include <sys/sysctl.h>
#include <err.h>
#include <errno.h>
#include <atf-c.h>
#define mib_name "kern.x86_pte_test.test"
#define MODULE_PATH "/usr/tests/modules/x86_pte_tester/x86_pte_tester.kmod"
#define MODULE_NAME "x86_pte_tester"
static struct {
size_t n_rwx;
size_t n_shstk;
bool kernel_map_with_low_ptes;
bool pte_is_user_accessible;
size_t n_user_space_is_kernel;
size_t n_kernel_space_is_user;
size_t n_svs_g_bit_set;
} x86_pte_results;
static void
fetch_results(void)
{
static bool fetched = false;
size_t len = sizeof(x86_pte_results);
char module_name[] = MODULE_NAME;
modctl_load_t params = {
.ml_filename = MODULE_PATH,
.ml_flags = MODCTL_NO_PROP,
};
int rv;
if (fetched)
return;
if (modctl(MODCTL_LOAD, ¶ms) != 0)
atf_tc_skip("loading '%s' module failed.", MODULE_NAME);
rv = sysctlbyname(mib_name, &x86_pte_results, &len, 0, 0);
ATF_REQUIRE_EQ(rv, 0);
if (modctl(MODCTL_UNLOAD, module_name) != 0)
warn("failed to unload module '%s'", MODULE_NAME);
fetched = true;
}
/* -------------------------------------------------------------------------- */
ATF_TC(rwx);
ATF_TC_HEAD(rwx, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure there is no RWX page in the kernel");
}
ATF_TC_BODY(rwx, tc)
{
fetch_results();
ATF_REQUIRE_EQ(x86_pte_results.n_rwx, 0);
}
/* -------------------------------------------------------------------------- */
ATF_TC(shstk);
ATF_TC_HEAD(shstk, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure there is no SHSTK page in the kernel");
}
ATF_TC_BODY(shstk, tc)
{
fetch_results();
atf_tc_expect_fail("there are %zu SHSTK pages",
x86_pte_results.n_shstk);
ATF_REQUIRE_EQ(x86_pte_results.n_shstk, 0);
}
/* -------------------------------------------------------------------------- */
ATF_TC(kernel_map_with_low_ptes);
ATF_TC_HEAD(kernel_map_with_low_ptes, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure the kernel map has no user mapping");
}
ATF_TC_BODY(kernel_map_with_low_ptes, tc)
{
fetch_results();
ATF_REQUIRE_EQ(x86_pte_results.kernel_map_with_low_ptes, false);
}
/* -------------------------------------------------------------------------- */
ATF_TC(pte_is_user_accessible);
ATF_TC_HEAD(pte_is_user_accessible, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure the PTE space does not have user permissions");
}
ATF_TC_BODY(pte_is_user_accessible, tc)
{
fetch_results();
ATF_REQUIRE_EQ(x86_pte_results.pte_is_user_accessible, false);
}
/* -------------------------------------------------------------------------- */
ATF_TC(user_space_is_kernel);
ATF_TC_HEAD(user_space_is_kernel, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure no page in the user space has kernel permissions");
}
ATF_TC_BODY(user_space_is_kernel, tc)
{
fetch_results();
ATF_REQUIRE_EQ(x86_pte_results.n_user_space_is_kernel, 0);
}
/* -------------------------------------------------------------------------- */
ATF_TC(kernel_space_is_user);
ATF_TC_HEAD(kernel_space_is_user, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure no page in the kernel space has user permissions");
}
ATF_TC_BODY(kernel_space_is_user, tc)
{
fetch_results();
ATF_REQUIRE_EQ(x86_pte_results.n_kernel_space_is_user, 0);
}
/* -------------------------------------------------------------------------- */
ATF_TC(svs_g_bit_set);
ATF_TC_HEAD(svs_g_bit_set, tc)
{
atf_tc_set_md_var(tc, "descr",
"ensure that no page in the SVS map has the G bit set");
}
ATF_TC_BODY(svs_g_bit_set, tc)
{
fetch_results();
if (x86_pte_results.n_svs_g_bit_set != (size_t)-1) {
ATF_REQUIRE_EQ(x86_pte_results.n_svs_g_bit_set, 0);
} else {
atf_tc_skip("SVS is disabled.");
}
}
/* -------------------------------------------------------------------------- */
ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tp, rwx);
ATF_TP_ADD_TC(tp, shstk);
ATF_TP_ADD_TC(tp, kernel_map_with_low_ptes);
ATF_TP_ADD_TC(tp, pte_is_user_accessible);
ATF_TP_ADD_TC(tp, user_space_is_kernel);
ATF_TP_ADD_TC(tp, kernel_space_is_user);
ATF_TP_ADD_TC(tp, svs_g_bit_set);
return atf_no_error();
}
