diff mbox series

[RFC,v2,8/8] selftest mm/mseal mprotect/munmap/mremap/mmap

Message ID 20231017090815.1067790-9-jeffxu@chromium.org (mailing list archive)
State Changes Requested
Headers show
Series Introduce mseal() syscall | expand

Commit Message

Jeff Xu Oct. 17, 2023, 9:08 a.m. UTC
From: Jeff Xu <jeffxu@google.com>

selftest for sealing mprotect/munmap/mremap/mmap

Signed-off-by: Jeff Xu <jeffxu@google.com>
---
 tools/testing/selftests/mm/Makefile     |    1 +
 tools/testing/selftests/mm/mseal_test.c | 1428 +++++++++++++++++++++++
 2 files changed, 1429 insertions(+)
 create mode 100644 tools/testing/selftests/mm/mseal_test.c

Comments

Muhammad Usama Anjum Oct. 20, 2023, 2:24 p.m. UTC | #1
On 10/17/23 2:08 PM, jeffxu@chromium.org wrote:
> From: Jeff Xu <jeffxu@google.com>
> 
> selftest for sealing mprotect/munmap/mremap/mmap
> 
> Signed-off-by: Jeff Xu <jeffxu@google.com>
> ---
>  tools/testing/selftests/mm/Makefile     |    1 +
>  tools/testing/selftests/mm/mseal_test.c | 1428 +++++++++++++++++++++++
Please add the new MSEAL config to tools/testing/selftests/mm/config.
Please add the generated object in tools/testing/selftests/mm/.gitignore file.

>  2 files changed, 1429 insertions(+)
>  create mode 100644 tools/testing/selftests/mm/mseal_test.c
> 
> diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
> index 6a9fc5693145..0c086cecc093 100644
> --- a/tools/testing/selftests/mm/Makefile
> +++ b/tools/testing/selftests/mm/Makefile
> @@ -59,6 +59,7 @@ TEST_GEN_FILES += mlock2-tests
>  TEST_GEN_FILES += mrelease_test
>  TEST_GEN_FILES += mremap_dontunmap
>  TEST_GEN_FILES += mremap_test
> +TEST_GEN_FILES += mseal_test
>  TEST_GEN_FILES += on-fault-limit
>  TEST_GEN_FILES += thuge-gen
>  TEST_GEN_FILES += transhuge-stress
> diff --git a/tools/testing/selftests/mm/mseal_test.c b/tools/testing/selftests/mm/mseal_test.c
> new file mode 100644
> index 000000000000..d6ae09729394
> --- /dev/null
> +++ b/tools/testing/selftests/mm/mseal_test.c
> @@ -0,0 +1,1428 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <sys/mman.h>
> +#include <stdint.h>
> +#include <unistd.h>
> +#include <string.h>
> +#include <sys/time.h>
> +#include <sys/resource.h>
> +#include <stdbool.h>
> +#include "../kselftest.h"
> +#include <syscall.h>
> +#include <errno.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <assert.h>
> +
> +#ifndef MM_SEAL_MSEAL
> +#define MM_SEAL_MSEAL 0x1
> +#endif
> +
> +#ifndef MM_SEAL_MPROTECT
> +#define MM_SEAL_MPROTECT 0x2
> +#endif
> +
> +#ifndef MM_SEAL_MUNMAP
> +#define MM_SEAL_MUNMAP 0x4
> +#endif
> +
> +#ifndef MM_SEAL_MMAP
> +#define MM_SEAL_MMAP 0x8
> +#endif
> +
> +#ifndef MM_SEAL_MREMAP
> +#define MM_SEAL_MREMAP 0x10
> +#endif
Please remove these. These macros would be picked up from the kernel
headers automatically.

> +
> +#ifndef DEBUG
> +#define LOG_TEST_ENTER()	{}
> +#else
> +#define LOG_TEST_ENTER()	{ printf("%s\n", __func__); }
> +#endif
> +
> +static int sys_mseal(void *start, size_t len, int types)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(__NR_mseal, start, len, types, 0);
> +	return sret;
> +}
> +
> +int sys_mprotect(void *ptr, size_t size, unsigned long prot)
Why aren't you using the mprotect() wrapper already provided by glibC? Same
question for other syscalls. Maybe you are trying to avoid some glibc magic?

> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(SYS_mprotect, ptr, size, prot);
> +	return sret;
> +}
> +
> +int sys_munmap(void *ptr, size_t size)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(SYS_munmap, ptr, size);
> +	return sret;
> +}
> +
> +static int sys_madvise(void *start, size_t len, int types)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(__NR_madvise, start, len, types);
> +	return sret;
> +}
> +
> +void *addr1 = (void *)0x50000000;
> +void *addr2 = (void *)0x50004000;
> +void *addr3 = (void *)0x50008000;
> +void setup_single_address(int size, void **ptrOut)
> +{
> +	void *ptr;
> +
> +	ptr = mmap(NULL, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> +	assert(ptr != (void *)-1);
MAP_FAILED inlace of -1

> +	*ptrOut = ptr;
> +}
> +
> +void setup_single_fixed_address(int size, void **ptrOut)
> +{
> +	void *ptr;
> +
> +	ptr = mmap(addr1, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> +	assert(ptr == (void *)addr1);
> +
> +	*ptrOut = ptr;
> +}
> +
> +void clean_single_address(void *ptr, int size)
> +{
> +	int ret;
> +
> +	ret = munmap(ptr, size);
> +	assert(!ret);
> +}
> +
> +void seal_mprotect_single_address(void *ptr, int size)
> +{
> +	int ret;
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +}
> +
> +static void test_seal_addseals(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	/* adding seal one by one */
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MMAP);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_addseals_combined(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	/* adding multiple seals */
> +	ret = sys_mseal(ptr, size,
> +			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MREMAP |
> +			MM_SEAL_MSEAL);
> +	assert(!ret);
The output should be conformed to the kselftets output format by using
ksft_exit_fail_msg() and ksft_test_result*() macros etc. Please find these
macros in kselftest.h.

> +
> +	/* not adding more seal type, so ok. */
> +	ret = sys_mseal(ptr, size,
> +			MM_SEAL_MMAP | MM_SEAL_MREMAP | MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	/* not adding more seal type, so ok. */
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_addseals_reject(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT | MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	/* MM_SEAL_MSEAL is set, so not allow new seal type . */
> +	ret = sys_mseal(ptr, size,
> +			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MMAP);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MMAP | MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_unmapped_start(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// munmap 2 pages from ptr.
Use consistent commenting style in the file.

> +	ret = sys_munmap(ptr, 2 * page_size);
> +	assert(!ret);
> +
> +	// mprotect will fail because 2 pages from ptr are unmapped.
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	assert(ret < 0);
> +
> +	// mseal will fail because 2 pages from ptr are unmapped.
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr + 2 * page_size, 2 * page_size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_unmapped_middle(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// munmap 2 pages from ptr + page.
> +	ret = sys_munmap(ptr + page_size, 2 * page_size);
> +	assert(!ret);
> +
> +	// mprotect will fail, since size is 4 pages.
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	assert(ret < 0);
> +
> +	// mseal will fail as well.
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	/* we still can add seal to the first page and last page*/
> +	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr + 3 * page_size, page_size,
> +			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_unmapped_end(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// unmap last 2 pages.
> +	ret = sys_munmap(ptr + 2 * page_size, 2 * page_size);
> +	assert(!ret);
> +
> +	//mprotect will fail since last 2 pages are unmapped.
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	assert(ret < 0);
> +
> +	//mseal will fail as well.
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	/* The first 2 pages is not sealed, and can add seals */
> +	ret = sys_mseal(ptr, 2 * page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_multiple_vmas(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// use mprotect to split the vma into 3.
> +	ret = sys_mprotect(ptr + page_size, 2 * page_size,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// mprotect will get applied to all 4 pages - 3 VMAs.
> +	ret = sys_mprotect(ptr, size, PROT_READ);
> +	assert(!ret);
> +
> +	// use mprotect to split the vma into 3.
> +	ret = sys_mprotect(ptr + page_size, 2 * page_size,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// mseal get applied to all 4 pages - 3 VMAs.
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	// verify additional seal type will fail after MM_SEAL_MSEAL set.
> +	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr + page_size, 2 * page_size,
> +			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr + 3 * page_size, page_size,
> +			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(ret < 0);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_split_start(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	/* use mprotect to split at middle */
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	/* seal the first page, this will split the VMA */
> +	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	/* can't add seal to the first page */
> +	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(ret < 0);
> +
> +	/* add seal to the remain 3 pages */
> +	ret = sys_mseal(ptr + page_size, 3 * page_size,
> +			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_split_end(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_fixed_address(size, &ptr);
> +
> +	/* use mprotect to split at middle */
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	/* seal the last page */
> +	ret = sys_mseal(ptr + 3 * page_size, page_size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	/* adding seal to the last page is rejected. */
> +	ret = sys_mseal(ptr + 3 * page_size, page_size,
> +			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(ret < 0);
> +
> +	/* Adding seals to the first 3 pages */
> +	ret = sys_mseal(ptr, 3 * page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_invalid_input(void)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_fixed_address(size, &ptr);
> +
> +	/* invalid flag */
> +	ret = sys_mseal(ptr, size, 0x20);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr, size, 0x31);
> +	assert(ret < 0);
> +
> +	ret = sys_mseal(ptr, size, 0x3F);
> +	assert(ret < 0);
> +
> +	/* unaligned address */
> +	ret = sys_mseal(ptr + 1, 2 * page_size, MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	/* length too big */
> +	ret = sys_mseal(ptr, 5 * page_size, MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	/* start is not in a valid VMA */
> +	ret = sys_mseal(ptr - page_size, 5 * page_size, MM_SEAL_MSEAL);
> +	assert(ret < 0);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_zero_length(void)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	ret = sys_mprotect(ptr, 0, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	/* seal 0 length will be OK, same as mprotect */
> +	ret = sys_mseal(ptr, 0, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	// verify the 4 pages are not sealed by previous call.
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_twice(void)
> +{
> +	LOG_TEST_ENTER();
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +
> +	setup_single_address(size, &ptr);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	// apply the same seal will be OK. idempotent.
> +	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size,
> +			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MREMAP |
> +			MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size,
> +			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MREMAP |
> +			MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_mprotect_single_address(ptr, size);
> +
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_start_mprotect(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_mprotect_single_address(ptr, page_size);
> +
> +	// the first page is sealed.
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	// pages after the first page is not sealed.
> +	ret = sys_mprotect(ptr + page_size, page_size * 3,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_end_mprotect(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_mprotect_single_address(ptr + page_size, 3 * page_size);
> +
> +	/* first page is not sealed */
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	/* last 3 page are sealed */
> +	ret = sys_mprotect(ptr + page_size, page_size * 3,
> +			PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_unalign_len(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_mprotect_single_address(ptr, page_size * 2 - 1);
> +
> +	// 2 pages are sealed.
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	ret = sys_mprotect(ptr + page_size * 2, page_size,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_unalign_len_variant_2(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +	if (seal)
> +		seal_mprotect_single_address(ptr, page_size * 2 + 1);
> +
> +	// 3 pages are sealed.
> +	ret = sys_mprotect(ptr, page_size * 3, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	ret = sys_mprotect(ptr + page_size * 3, page_size,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_two_vma(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	/* use mprotect to split */
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	if (seal)
> +		seal_mprotect_single_address(ptr, page_size * 4);
> +
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	ret = sys_mprotect(ptr + page_size * 2, page_size * 2,
> +			PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_two_vma_with_split(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// use mprotect to split as two vma.
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// mseal can apply across 2 vma, also split them.
> +	if (seal)
> +		seal_mprotect_single_address(ptr + page_size, page_size * 2);
> +
> +	// the first page is not sealed.
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// the second page is sealed.
> +	ret = sys_mprotect(ptr + page_size, page_size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	// the third page is sealed.
> +	ret = sys_mprotect(ptr + 2 * page_size, page_size,
> +			PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	// the fouth page is not sealed.
> +	ret = sys_mprotect(ptr + 3 * page_size, page_size,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_partial_mprotect(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// seal one page.
> +	if (seal)
> +		seal_mprotect_single_address(ptr, page_size);
> +
> +	// mprotect first 2 page will fail, since the first page are sealed.
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_two_vma_with_gap(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// use mprotect to split.
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// use mprotect to split.
> +	ret = sys_mprotect(ptr + 3 * page_size, page_size,
> +			PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// use munmap to free two pages in the middle
> +	ret = sys_munmap(ptr + page_size, 2 * page_size);
> +	assert(!ret);
> +
> +	// mprotect will fail, because there is a gap in the address.
> +	// notes, internally mprotect still updated the first page.
> +	ret = sys_mprotect(ptr, 4 * page_size, PROT_READ);
> +	assert(ret < 0);
> +
> +	// mseal will fail as well.
> +	ret = sys_mseal(ptr, 4 * page_size, MM_SEAL_MPROTECT);
> +	assert(ret < 0);
> +
> +	// unlike mprotect, the first page is not sealed.
> +	ret = sys_mprotect(ptr, page_size, PROT_READ);
> +	assert(ret == 0);
> +
> +	// the last page is not sealed.
> +	ret = sys_mprotect(ptr + 3 * page_size, page_size, PROT_READ);
> +	assert(ret == 0);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_split(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	//use mprotect to split.
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	//seal all 4 pages.
> +	if (seal) {
> +		ret = sys_mseal(ptr, 4 * page_size, MM_SEAL_MPROTECT);
> +		assert(!ret);
> +	}
> +
> +	//madvice is OK.
> +	ret = sys_madvise(ptr, page_size * 2, MADV_WILLNEED);
> +	assert(!ret);
> +
> +	//mprotect is sealed.
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +
> +	ret = sys_mprotect(ptr + 2 * page_size, 2 * page_size, PROT_READ);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_mprotect_merge(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// use mprotect to split one page.
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	// seal first two pages.
> +	if (seal) {
> +		ret = sys_mseal(ptr, 2 * page_size, MM_SEAL_MPROTECT);
> +		assert(!ret);
> +	}
> +
> +	ret = sys_madvise(ptr, page_size, MADV_WILLNEED);
> +	assert(!ret);
> +
> +	// 2 pages are sealed.
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	// last 2 pages are not sealed.
> +	ret = sys_mprotect(ptr + 2 * page_size, 2 * page_size, PROT_READ);
> +	assert(ret == 0);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +static void test_seal_munmap(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MUNMAP);
> +		assert(!ret);
> +	}
> +
> +	// 4 pages are sealed.
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +}
> +
> +/*
> + * allocate 4 pages,
> + * use mprotect to split it as two VMAs
> + * seal the whole range
> + * munmap will fail on both
> + */
> +static void test_seal_munmap_two_vma(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	/* use mprotect to split */
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	assert(!ret);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MUNMAP);
> +		assert(!ret);
> +	}
> +
> +	ret = sys_munmap(ptr, page_size * 2);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +
> +	ret = sys_munmap(ptr + page_size, page_size * 2);
> +	if (seal)
> +		assert(ret < 0);
> +	else
> +		assert(!ret);
> +}
> +
> +/*
> + * allocate a VMA with 4 pages.
> + * munmap the middle 2 pages.
> + * seal the whole 4 pages, will fail.
> + * note: one of the pages are sealed
> + * munmap the first page will be OK.
> + * munmap the last page will be OK.
> + */
> +static void test_seal_munmap_vma_with_gap(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	ret = sys_munmap(ptr + page_size, page_size * 2);
> +	assert(!ret);
> +
> +	if (seal) {
> +		// can't have gap in the middle.
> +		ret = sys_mseal(ptr, size, MM_SEAL_MUNMAP);
> +		assert(ret < 0);
> +	}
> +
> +	ret = sys_munmap(ptr, page_size);
> +	assert(!ret);
> +
> +	ret = sys_munmap(ptr + page_size * 2, page_size);
> +	assert(!ret);
> +
> +	ret = sys_munmap(ptr, size);
> +	assert(!ret);
> +}
> +
> +static void test_munmap_start_freed(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	// unmap the first page.
> +	ret = sys_munmap(ptr, page_size);
> +	assert(!ret);
> +
> +	// seal the last 3 pages.
> +	if (seal) {
> +		ret = sys_mseal(ptr + page_size, 3 * page_size, MM_SEAL_MUNMAP);
> +		assert(!ret);
> +	}
> +
> +	// unmap from the first page.
> +	ret = sys_munmap(ptr, size);
> +	if (seal) {
> +		assert(ret < 0);
> +
> +		// use mprotect to verify page is not unmapped.
> +		ret = sys_mprotect(ptr + page_size, 3 * page_size, PROT_READ);
> +		assert(!ret);
> +	} else
> +		// note: this will be OK, even the first page is
> +		// already unmapped.
> +		assert(!ret);
> +}
> +
> +static void test_munmap_end_freed(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +	// unmap last page.
> +	ret = sys_munmap(ptr + page_size * 3, page_size);
> +	assert(!ret);
> +
> +	// seal the first 3 pages.
> +	if (seal) {
> +		ret = sys_mseal(ptr, 3 * page_size, MM_SEAL_MUNMAP);
> +		assert(!ret);
> +	}
> +
> +	// unmap all pages.
> +	ret = sys_munmap(ptr, size);
> +	if (seal) {
> +		assert(ret < 0);
> +
> +		// use mprotect to verify page is not unmapped.
> +		ret = sys_mprotect(ptr, 3 * page_size, PROT_READ);
> +		assert(!ret);
> +	} else
> +		assert(!ret);
> +}
> +
> +static void test_munmap_middle_freed(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +	// unmap 2 pages in the middle.
> +	ret = sys_munmap(ptr + page_size, page_size * 2);
> +	assert(!ret);
> +
> +	// seal the first page.
> +	if (seal) {
> +		ret = sys_mseal(ptr, page_size, MM_SEAL_MUNMAP);
> +		assert(!ret);
> +	}
> +
> +	// munmap all 4 pages.
> +	ret = sys_munmap(ptr, size);
> +	if (seal) {
> +		assert(ret < 0);
> +
> +		// use mprotect to verify page is not unmapped.
> +		ret = sys_mprotect(ptr, page_size, PROT_READ);
> +		assert(!ret);
> +	} else
> +		assert(!ret);
> +}
> +
> +void test_seal_mremap_shrink(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// shrink from 4 pages to 2 pages.
> +	ret2 = mremap(ptr, size, 2 * page_size, 0, 0);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else {
> +		assert(ret2 != MAP_FAILED);
> +		clean_single_address(ret2, 2 * page_size);
> +	}
> +	clean_single_address(ptr, size);
> +}
> +
> +void test_seal_mremap_expand(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +	// ummap last 2 pages.
> +	ret = sys_munmap(ptr + 2 * page_size, 2 * page_size);
> +	assert(!ret);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, 2 * page_size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// expand from 2 page to 4 pages.
> +	ret2 = mremap(ptr, 2 * page_size, 4 * page_size, 0, 0);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else {
> +		assert(ret2 == ptr);
> +		clean_single_address(ret2, 4 * page_size);
> +	}
> +	clean_single_address(ptr, size);
> +}
> +
> +void test_seal_mremap_move(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// move from ptr to fixed address.
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else {
> +		assert(ret2 != MAP_FAILED);
> +		clean_single_address(ret2, size);
> +	}
> +	clean_single_address(ptr, size);
> +}
> +
> +void test_seal_mmap_overwrite_prot(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MMAP);
> +		assert(!ret);
> +	}
> +
> +	// use mmap to change protection.
> +	ret2 = mmap(ptr, size, PROT_NONE,
> +			MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else
> +		assert(ret2 == ptr);
> +
> +	clean_single_address(ptr, size);
> +}
> +
> +void test_seal_mremap_shrink_fixed(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	void *newAddr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +	setup_single_fixed_address(size, &newAddr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// mremap to move and shrink to fixed address
> +	ret2 = mremap(ptr, size, 2 * page_size, MREMAP_MAYMOVE | MREMAP_FIXED,
> +			newAddr);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else
> +		assert(ret2 == newAddr);
> +
> +	clean_single_address(ptr, size);
> +	clean_single_address(newAddr, size);
> +}
> +
> +void test_seal_mremap_expand_fixed(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	void *newAddr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(page_size, &ptr);
> +	setup_single_fixed_address(size, &newAddr);
> +
> +	if (seal) {
> +		ret = sys_mseal(newAddr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// mremap to move and expand to fixed address
> +	ret2 = mremap(ptr, page_size, size, MREMAP_MAYMOVE | MREMAP_FIXED,
> +			newAddr);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else
> +		assert(ret2 == newAddr);
> +
> +	clean_single_address(ptr, page_size);
> +	clean_single_address(newAddr, size);
> +}
> +
> +void test_seal_mremap_move_fixed(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	void *newAddr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +	setup_single_fixed_address(size, &newAddr);
> +
> +	if (seal) {
> +		ret = sys_mseal(newAddr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// mremap to move to fixed address
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_FIXED, newAddr);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else
> +		assert(ret2 == newAddr);
> +
> +	clean_single_address(ptr, page_size);
> +	clean_single_address(newAddr, size);
> +}
> +
> +void test_seal_mremap_move_fixed_zero(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	void *newAddr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	/*
> +	 * MREMAP_FIXED can move the mapping to zero address
> +	 */
> +	ret2 = mremap(ptr, size, 2 * page_size, MREMAP_MAYMOVE | MREMAP_FIXED,
> +			0);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else {
> +		assert(ret2 == 0);
> +		clean_single_address(ret2, 2 * page_size);
> +	}
> +	clean_single_address(ptr, size);
> +}
> +
> +void test_seal_mremap_move_dontunmap(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	void *newAddr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	// mremap to move, and don't unmap src addr.
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP, 0);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else {
> +		assert(ret2 != MAP_FAILED);
> +		clean_single_address(ret2, size);
> +	}
> +
> +	clean_single_address(ptr, page_size);
> +}
> +
> +void test_seal_mremap_move_dontunmap_anyaddr(bool seal)
> +{
> +	LOG_TEST_ENTER();
> +	void *ptr;
> +	void *newAddr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
> +		assert(!ret);
> +	}
> +
> +	/*
> +	 * The 0xdeaddead should not have effect on dest addr
> +	 * when MREMAP_DONTUNMAP is set.
> +	 */
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP,
> +			0xdeaddead);
> +	if (seal) {
> +		assert(ret2 == MAP_FAILED);
> +		assert(errno == EACCES);
> +	} else {
> +		assert(ret2 != MAP_FAILED);
> +		assert((long)ret2 != 0xdeaddead);
> +		clean_single_address(ret2, size);
> +	}
> +
> +	clean_single_address(ptr, page_size);
> +}
> +
> +int main(int argc, char **argv)
> +{
> +	test_seal_invalid_input();
> +	test_seal_addseals();
> +	test_seal_addseals_combined();
> +	test_seal_addseals_reject();
> +	test_seal_unmapped_start();
> +	test_seal_unmapped_middle();
> +	test_seal_unmapped_end();
> +	test_seal_multiple_vmas();
> +	test_seal_split_start();
> +	test_seal_split_end();
> +
> +	test_seal_zero_length();
> +	test_seal_twice();
> +
> +	test_seal_mprotect(false);
> +	test_seal_mprotect(true);
> +
> +	test_seal_start_mprotect(false);
> +	test_seal_start_mprotect(true);
> +
> +	test_seal_end_mprotect(false);
> +	test_seal_end_mprotect(true);
> +
> +	test_seal_mprotect_unalign_len(false);
> +	test_seal_mprotect_unalign_len(true);
> +
> +	test_seal_mprotect_unalign_len_variant_2(false);
> +	test_seal_mprotect_unalign_len_variant_2(true);
> +
> +	test_seal_mprotect_two_vma(false);
> +	test_seal_mprotect_two_vma(true);
> +
> +	test_seal_mprotect_two_vma_with_split(false);
> +	test_seal_mprotect_two_vma_with_split(true);
> +
> +	test_seal_mprotect_partial_mprotect(false);
> +	test_seal_mprotect_partial_mprotect(true);
> +
> +	test_seal_mprotect_two_vma_with_gap(false);
> +	test_seal_mprotect_two_vma_with_gap(true);
> +
> +	test_seal_mprotect_merge(false);
> +	test_seal_mprotect_merge(true);
> +
> +	test_seal_mprotect_split(false);
> +	test_seal_mprotect_split(true);
> +
> +	test_seal_munmap(false);
> +	test_seal_munmap(true);
> +	test_seal_munmap_two_vma(false);
> +	test_seal_munmap_two_vma(true);
> +	test_seal_munmap_vma_with_gap(false);
> +	test_seal_munmap_vma_with_gap(true);
> +
> +	test_munmap_start_freed(false);
> +	test_munmap_start_freed(true);
> +	test_munmap_middle_freed(false);
> +	test_munmap_middle_freed(true);
> +	test_munmap_end_freed(false);
> +	test_munmap_end_freed(true);
> +
> +	test_seal_mremap_shrink(false);
> +	test_seal_mremap_shrink(true);
> +	test_seal_mremap_expand(false);
> +	test_seal_mremap_expand(true);
> +	test_seal_mremap_move(false);
> +	test_seal_mremap_move(true);
> +
> +	test_seal_mremap_shrink_fixed(false);
> +	test_seal_mremap_shrink_fixed(true);
> +	test_seal_mremap_expand_fixed(false);
> +	test_seal_mremap_expand_fixed(true);
> +	test_seal_mremap_move_fixed(false);
> +	test_seal_mremap_move_fixed(true);
> +	test_seal_mremap_move_dontunmap(false);
> +	test_seal_mremap_move_dontunmap(true);
> +	test_seal_mremap_move_fixed_zero(false);
> +	test_seal_mremap_move_fixed_zero(true);
> +	test_seal_mremap_move_dontunmap_anyaddr(false);
> +	test_seal_mremap_move_dontunmap_anyaddr(true);
> +
> +	test_seal_mmap_overwrite_prot(false);
> +	test_seal_mmap_overwrite_prot(true);
> +
> +	printf("OK\n");
> +	return 0;
> +}
Peter Zijlstra Oct. 20, 2023, 3:23 p.m. UTC | #2
On Fri, Oct 20, 2023 at 07:24:03PM +0500, Muhammad Usama Anjum wrote:

> Please remove these. These macros would be picked up from the kernel
> headers automatically.

As per the previous discussions, how does that work if you have O= build
directories?

I find this push to force people to do 'make headers' in order to use
simple selftests quite misguided. You're making it *harder* to use,
leading to less use.
Muhammad Usama Anjum Oct. 20, 2023, 4:33 p.m. UTC | #3
On 10/20/23 8:23 PM, Peter Zijlstra wrote:
> On Fri, Oct 20, 2023 at 07:24:03PM +0500, Muhammad Usama Anjum wrote:
> 
>> Please remove these. These macros would be picked up from the kernel
>> headers automatically.
> 
> As per the previous discussions, how does that work if you have O= build
> directories?
Then headers should be prepared in that O= directory first.
make headers O=abc && make -C tools/testing/selftests O=abc

> 
> I find this push to force people to do 'make headers' in order to use
> simple selftests quite misguided. You're making it *harder* to use,
> leading to less use.
I'm just following what we have been doing over selftests mailing list to
fix build issues in different use cases and kselfest.rst. Let me share the
history:

Around 2 years ago, selftest Makefile used to prepare kernel headers from
source automatically and include them to build selftests. It had several
bugs. So they separated the header preparation from selftest build. After a
while people started getting build failures because they weren't building
headers which were previously built automatically. So someone had written a
patch (already in v6.6-rc6) to show informative error if headers aren't
present. So now selftests can't be built until headers are built.

The understanding here is that selftests come with kernel source and they
should be built using in-source kernel headers as people don't always have
updated headers. I think, if someone want to build just one selftest
without doing make headers, he should install kernel headers from source
before doing so instead of adding duplicate defines in the test itself. It
helps while development to not to keep the duplicate copy of these macros
in selftest as well.
diff mbox series

Patch

diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
index 6a9fc5693145..0c086cecc093 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -59,6 +59,7 @@  TEST_GEN_FILES += mlock2-tests
 TEST_GEN_FILES += mrelease_test
 TEST_GEN_FILES += mremap_dontunmap
 TEST_GEN_FILES += mremap_test
+TEST_GEN_FILES += mseal_test
 TEST_GEN_FILES += on-fault-limit
 TEST_GEN_FILES += thuge-gen
 TEST_GEN_FILES += transhuge-stress
diff --git a/tools/testing/selftests/mm/mseal_test.c b/tools/testing/selftests/mm/mseal_test.c
new file mode 100644
index 000000000000..d6ae09729394
--- /dev/null
+++ b/tools/testing/selftests/mm/mseal_test.c
@@ -0,0 +1,1428 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sys/mman.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <stdbool.h>
+#include "../kselftest.h"
+#include <syscall.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#ifndef MM_SEAL_MSEAL
+#define MM_SEAL_MSEAL 0x1
+#endif
+
+#ifndef MM_SEAL_MPROTECT
+#define MM_SEAL_MPROTECT 0x2
+#endif
+
+#ifndef MM_SEAL_MUNMAP
+#define MM_SEAL_MUNMAP 0x4
+#endif
+
+#ifndef MM_SEAL_MMAP
+#define MM_SEAL_MMAP 0x8
+#endif
+
+#ifndef MM_SEAL_MREMAP
+#define MM_SEAL_MREMAP 0x10
+#endif
+
+#ifndef DEBUG
+#define LOG_TEST_ENTER()	{}
+#else
+#define LOG_TEST_ENTER()	{ printf("%s\n", __func__); }
+#endif
+
+static int sys_mseal(void *start, size_t len, int types)
+{
+	int sret;
+
+	errno = 0;
+	sret = syscall(__NR_mseal, start, len, types, 0);
+	return sret;
+}
+
+int sys_mprotect(void *ptr, size_t size, unsigned long prot)
+{
+	int sret;
+
+	errno = 0;
+	sret = syscall(SYS_mprotect, ptr, size, prot);
+	return sret;
+}
+
+int sys_munmap(void *ptr, size_t size)
+{
+	int sret;
+
+	errno = 0;
+	sret = syscall(SYS_munmap, ptr, size);
+	return sret;
+}
+
+static int sys_madvise(void *start, size_t len, int types)
+{
+	int sret;
+
+	errno = 0;
+	sret = syscall(__NR_madvise, start, len, types);
+	return sret;
+}
+
+void *addr1 = (void *)0x50000000;
+void *addr2 = (void *)0x50004000;
+void *addr3 = (void *)0x50008000;
+void setup_single_address(int size, void **ptrOut)
+{
+	void *ptr;
+
+	ptr = mmap(NULL, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	assert(ptr != (void *)-1);
+	*ptrOut = ptr;
+}
+
+void setup_single_fixed_address(int size, void **ptrOut)
+{
+	void *ptr;
+
+	ptr = mmap(addr1, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	assert(ptr == (void *)addr1);
+
+	*ptrOut = ptr;
+}
+
+void clean_single_address(void *ptr, int size)
+{
+	int ret;
+
+	ret = munmap(ptr, size);
+	assert(!ret);
+}
+
+void seal_mprotect_single_address(void *ptr, int size)
+{
+	int ret;
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
+	assert(!ret);
+}
+
+static void test_seal_addseals(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	/* adding seal one by one */
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MMAP);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_addseals_combined(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	/* adding multiple seals */
+	ret = sys_mseal(ptr, size,
+			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MREMAP |
+			MM_SEAL_MSEAL);
+	assert(!ret);
+
+	/* not adding more seal type, so ok. */
+	ret = sys_mseal(ptr, size,
+			MM_SEAL_MMAP | MM_SEAL_MREMAP | MM_SEAL_MSEAL);
+	assert(!ret);
+
+	/* not adding more seal type, so ok. */
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_addseals_reject(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT | MM_SEAL_MSEAL);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	/* MM_SEAL_MSEAL is set, so not allow new seal type . */
+	ret = sys_mseal(ptr, size,
+			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MMAP);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MMAP | MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_unmapped_start(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	// munmap 2 pages from ptr.
+	ret = sys_munmap(ptr, 2 * page_size);
+	assert(!ret);
+
+	// mprotect will fail because 2 pages from ptr are unmapped.
+	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
+	assert(ret < 0);
+
+	// mseal will fail because 2 pages from ptr are unmapped.
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr + 2 * page_size, 2 * page_size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_unmapped_middle(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	// munmap 2 pages from ptr + page.
+	ret = sys_munmap(ptr + page_size, 2 * page_size);
+	assert(!ret);
+
+	// mprotect will fail, since size is 4 pages.
+	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
+	assert(ret < 0);
+
+	// mseal will fail as well.
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	/* we still can add seal to the first page and last page*/
+	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	ret = sys_mseal(ptr + 3 * page_size, page_size,
+			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_unmapped_end(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	// unmap last 2 pages.
+	ret = sys_munmap(ptr + 2 * page_size, 2 * page_size);
+	assert(!ret);
+
+	//mprotect will fail since last 2 pages are unmapped.
+	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
+	assert(ret < 0);
+
+	//mseal will fail as well.
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	/* The first 2 pages is not sealed, and can add seals */
+	ret = sys_mseal(ptr, 2 * page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_multiple_vmas(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	// use mprotect to split the vma into 3.
+	ret = sys_mprotect(ptr + page_size, 2 * page_size,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// mprotect will get applied to all 4 pages - 3 VMAs.
+	ret = sys_mprotect(ptr, size, PROT_READ);
+	assert(!ret);
+
+	// use mprotect to split the vma into 3.
+	ret = sys_mprotect(ptr + page_size, 2 * page_size,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// mseal get applied to all 4 pages - 3 VMAs.
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	// verify additional seal type will fail after MM_SEAL_MSEAL set.
+	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr + page_size, 2 * page_size,
+			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr + 3 * page_size, page_size,
+			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(ret < 0);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_split_start(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	/* use mprotect to split at middle */
+	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	/* seal the first page, this will split the VMA */
+	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	/* can't add seal to the first page */
+	ret = sys_mseal(ptr, page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(ret < 0);
+
+	/* add seal to the remain 3 pages */
+	ret = sys_mseal(ptr + page_size, 3 * page_size,
+			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_split_end(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_fixed_address(size, &ptr);
+
+	/* use mprotect to split at middle */
+	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	/* seal the last page */
+	ret = sys_mseal(ptr + 3 * page_size, page_size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	/* adding seal to the last page is rejected. */
+	ret = sys_mseal(ptr + 3 * page_size, page_size,
+			MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(ret < 0);
+
+	/* Adding seals to the first 3 pages */
+	ret = sys_mseal(ptr, 3 * page_size, MM_SEAL_MSEAL | MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_invalid_input(void)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_fixed_address(size, &ptr);
+
+	/* invalid flag */
+	ret = sys_mseal(ptr, size, 0x20);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr, size, 0x31);
+	assert(ret < 0);
+
+	ret = sys_mseal(ptr, size, 0x3F);
+	assert(ret < 0);
+
+	/* unaligned address */
+	ret = sys_mseal(ptr + 1, 2 * page_size, MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	/* length too big */
+	ret = sys_mseal(ptr, 5 * page_size, MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	/* start is not in a valid VMA */
+	ret = sys_mseal(ptr - page_size, 5 * page_size, MM_SEAL_MSEAL);
+	assert(ret < 0);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_zero_length(void)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	ret = sys_mprotect(ptr, 0, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	/* seal 0 length will be OK, same as mprotect */
+	ret = sys_mseal(ptr, 0, MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	// verify the 4 pages are not sealed by previous call.
+	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_twice(void)
+{
+	LOG_TEST_ENTER();
+	int ret;
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+
+	setup_single_address(size, &ptr);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	// apply the same seal will be OK. idempotent.
+	ret = sys_mseal(ptr, size, MM_SEAL_MPROTECT);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size,
+			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MREMAP |
+			MM_SEAL_MSEAL);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size,
+			MM_SEAL_MPROTECT | MM_SEAL_MMAP | MM_SEAL_MREMAP |
+			MM_SEAL_MSEAL);
+	assert(!ret);
+
+	ret = sys_mseal(ptr, size, MM_SEAL_MSEAL);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	if (seal)
+		seal_mprotect_single_address(ptr, size);
+
+	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_start_mprotect(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	if (seal)
+		seal_mprotect_single_address(ptr, page_size);
+
+	// the first page is sealed.
+	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	// pages after the first page is not sealed.
+	ret = sys_mprotect(ptr + page_size, page_size * 3,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_end_mprotect(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	if (seal)
+		seal_mprotect_single_address(ptr + page_size, 3 * page_size);
+
+	/* first page is not sealed */
+	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	/* last 3 page are sealed */
+	ret = sys_mprotect(ptr + page_size, page_size * 3,
+			PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_unalign_len(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	if (seal)
+		seal_mprotect_single_address(ptr, page_size * 2 - 1);
+
+	// 2 pages are sealed.
+	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	ret = sys_mprotect(ptr + page_size * 2, page_size,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_unalign_len_variant_2(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+	if (seal)
+		seal_mprotect_single_address(ptr, page_size * 2 + 1);
+
+	// 3 pages are sealed.
+	ret = sys_mprotect(ptr, page_size * 3, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	ret = sys_mprotect(ptr + page_size * 3, page_size,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_two_vma(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	/* use mprotect to split */
+	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	if (seal)
+		seal_mprotect_single_address(ptr, page_size * 4);
+
+	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	ret = sys_mprotect(ptr + page_size * 2, page_size * 2,
+			PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_two_vma_with_split(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	// use mprotect to split as two vma.
+	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// mseal can apply across 2 vma, also split them.
+	if (seal)
+		seal_mprotect_single_address(ptr + page_size, page_size * 2);
+
+	// the first page is not sealed.
+	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// the second page is sealed.
+	ret = sys_mprotect(ptr + page_size, page_size, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	// the third page is sealed.
+	ret = sys_mprotect(ptr + 2 * page_size, page_size,
+			PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	// the fouth page is not sealed.
+	ret = sys_mprotect(ptr + 3 * page_size, page_size,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_partial_mprotect(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	// seal one page.
+	if (seal)
+		seal_mprotect_single_address(ptr, page_size);
+
+	// mprotect first 2 page will fail, since the first page are sealed.
+	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ | PROT_WRITE);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_two_vma_with_gap(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	// use mprotect to split.
+	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// use mprotect to split.
+	ret = sys_mprotect(ptr + 3 * page_size, page_size,
+			PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// use munmap to free two pages in the middle
+	ret = sys_munmap(ptr + page_size, 2 * page_size);
+	assert(!ret);
+
+	// mprotect will fail, because there is a gap in the address.
+	// notes, internally mprotect still updated the first page.
+	ret = sys_mprotect(ptr, 4 * page_size, PROT_READ);
+	assert(ret < 0);
+
+	// mseal will fail as well.
+	ret = sys_mseal(ptr, 4 * page_size, MM_SEAL_MPROTECT);
+	assert(ret < 0);
+
+	// unlike mprotect, the first page is not sealed.
+	ret = sys_mprotect(ptr, page_size, PROT_READ);
+	assert(ret == 0);
+
+	// the last page is not sealed.
+	ret = sys_mprotect(ptr + 3 * page_size, page_size, PROT_READ);
+	assert(ret == 0);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_split(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	//use mprotect to split.
+	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	//seal all 4 pages.
+	if (seal) {
+		ret = sys_mseal(ptr, 4 * page_size, MM_SEAL_MPROTECT);
+		assert(!ret);
+	}
+
+	//madvice is OK.
+	ret = sys_madvise(ptr, page_size * 2, MADV_WILLNEED);
+	assert(!ret);
+
+	//mprotect is sealed.
+	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+
+	ret = sys_mprotect(ptr + 2 * page_size, 2 * page_size, PROT_READ);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_mprotect_merge(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	// use mprotect to split one page.
+	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	// seal first two pages.
+	if (seal) {
+		ret = sys_mseal(ptr, 2 * page_size, MM_SEAL_MPROTECT);
+		assert(!ret);
+	}
+
+	ret = sys_madvise(ptr, page_size, MADV_WILLNEED);
+	assert(!ret);
+
+	// 2 pages are sealed.
+	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	// last 2 pages are not sealed.
+	ret = sys_mprotect(ptr + 2 * page_size, 2 * page_size, PROT_READ);
+	assert(ret == 0);
+
+	clean_single_address(ptr, size);
+}
+
+static void test_seal_munmap(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MUNMAP);
+		assert(!ret);
+	}
+
+	// 4 pages are sealed.
+	ret = sys_munmap(ptr, size);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+}
+
+/*
+ * allocate 4 pages,
+ * use mprotect to split it as two VMAs
+ * seal the whole range
+ * munmap will fail on both
+ */
+static void test_seal_munmap_two_vma(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	/* use mprotect to split */
+	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
+	assert(!ret);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MUNMAP);
+		assert(!ret);
+	}
+
+	ret = sys_munmap(ptr, page_size * 2);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+
+	ret = sys_munmap(ptr + page_size, page_size * 2);
+	if (seal)
+		assert(ret < 0);
+	else
+		assert(!ret);
+}
+
+/*
+ * allocate a VMA with 4 pages.
+ * munmap the middle 2 pages.
+ * seal the whole 4 pages, will fail.
+ * note: one of the pages are sealed
+ * munmap the first page will be OK.
+ * munmap the last page will be OK.
+ */
+static void test_seal_munmap_vma_with_gap(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	ret = sys_munmap(ptr + page_size, page_size * 2);
+	assert(!ret);
+
+	if (seal) {
+		// can't have gap in the middle.
+		ret = sys_mseal(ptr, size, MM_SEAL_MUNMAP);
+		assert(ret < 0);
+	}
+
+	ret = sys_munmap(ptr, page_size);
+	assert(!ret);
+
+	ret = sys_munmap(ptr + page_size * 2, page_size);
+	assert(!ret);
+
+	ret = sys_munmap(ptr, size);
+	assert(!ret);
+}
+
+static void test_munmap_start_freed(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+
+	// unmap the first page.
+	ret = sys_munmap(ptr, page_size);
+	assert(!ret);
+
+	// seal the last 3 pages.
+	if (seal) {
+		ret = sys_mseal(ptr + page_size, 3 * page_size, MM_SEAL_MUNMAP);
+		assert(!ret);
+	}
+
+	// unmap from the first page.
+	ret = sys_munmap(ptr, size);
+	if (seal) {
+		assert(ret < 0);
+
+		// use mprotect to verify page is not unmapped.
+		ret = sys_mprotect(ptr + page_size, 3 * page_size, PROT_READ);
+		assert(!ret);
+	} else
+		// note: this will be OK, even the first page is
+		// already unmapped.
+		assert(!ret);
+}
+
+static void test_munmap_end_freed(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+	// unmap last page.
+	ret = sys_munmap(ptr + page_size * 3, page_size);
+	assert(!ret);
+
+	// seal the first 3 pages.
+	if (seal) {
+		ret = sys_mseal(ptr, 3 * page_size, MM_SEAL_MUNMAP);
+		assert(!ret);
+	}
+
+	// unmap all pages.
+	ret = sys_munmap(ptr, size);
+	if (seal) {
+		assert(ret < 0);
+
+		// use mprotect to verify page is not unmapped.
+		ret = sys_mprotect(ptr, 3 * page_size, PROT_READ);
+		assert(!ret);
+	} else
+		assert(!ret);
+}
+
+static void test_munmap_middle_freed(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+
+	setup_single_address(size, &ptr);
+	// unmap 2 pages in the middle.
+	ret = sys_munmap(ptr + page_size, page_size * 2);
+	assert(!ret);
+
+	// seal the first page.
+	if (seal) {
+		ret = sys_mseal(ptr, page_size, MM_SEAL_MUNMAP);
+		assert(!ret);
+	}
+
+	// munmap all 4 pages.
+	ret = sys_munmap(ptr, size);
+	if (seal) {
+		assert(ret < 0);
+
+		// use mprotect to verify page is not unmapped.
+		ret = sys_mprotect(ptr, page_size, PROT_READ);
+		assert(!ret);
+	} else
+		assert(!ret);
+}
+
+void test_seal_mremap_shrink(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// shrink from 4 pages to 2 pages.
+	ret2 = mremap(ptr, size, 2 * page_size, 0, 0);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else {
+		assert(ret2 != MAP_FAILED);
+		clean_single_address(ret2, 2 * page_size);
+	}
+	clean_single_address(ptr, size);
+}
+
+void test_seal_mremap_expand(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+	// ummap last 2 pages.
+	ret = sys_munmap(ptr + 2 * page_size, 2 * page_size);
+	assert(!ret);
+
+	if (seal) {
+		ret = sys_mseal(ptr, 2 * page_size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// expand from 2 page to 4 pages.
+	ret2 = mremap(ptr, 2 * page_size, 4 * page_size, 0, 0);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else {
+		assert(ret2 == ptr);
+		clean_single_address(ret2, 4 * page_size);
+	}
+	clean_single_address(ptr, size);
+}
+
+void test_seal_mremap_move(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// move from ptr to fixed address.
+	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else {
+		assert(ret2 != MAP_FAILED);
+		clean_single_address(ret2, size);
+	}
+	clean_single_address(ptr, size);
+}
+
+void test_seal_mmap_overwrite_prot(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MMAP);
+		assert(!ret);
+	}
+
+	// use mmap to change protection.
+	ret2 = mmap(ptr, size, PROT_NONE,
+			MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else
+		assert(ret2 == ptr);
+
+	clean_single_address(ptr, size);
+}
+
+void test_seal_mremap_shrink_fixed(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	void *newAddr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+	setup_single_fixed_address(size, &newAddr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// mremap to move and shrink to fixed address
+	ret2 = mremap(ptr, size, 2 * page_size, MREMAP_MAYMOVE | MREMAP_FIXED,
+			newAddr);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else
+		assert(ret2 == newAddr);
+
+	clean_single_address(ptr, size);
+	clean_single_address(newAddr, size);
+}
+
+void test_seal_mremap_expand_fixed(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	void *newAddr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(page_size, &ptr);
+	setup_single_fixed_address(size, &newAddr);
+
+	if (seal) {
+		ret = sys_mseal(newAddr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// mremap to move and expand to fixed address
+	ret2 = mremap(ptr, page_size, size, MREMAP_MAYMOVE | MREMAP_FIXED,
+			newAddr);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else
+		assert(ret2 == newAddr);
+
+	clean_single_address(ptr, page_size);
+	clean_single_address(newAddr, size);
+}
+
+void test_seal_mremap_move_fixed(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	void *newAddr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+	setup_single_fixed_address(size, &newAddr);
+
+	if (seal) {
+		ret = sys_mseal(newAddr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// mremap to move to fixed address
+	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_FIXED, newAddr);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else
+		assert(ret2 == newAddr);
+
+	clean_single_address(ptr, page_size);
+	clean_single_address(newAddr, size);
+}
+
+void test_seal_mremap_move_fixed_zero(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	void *newAddr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	/*
+	 * MREMAP_FIXED can move the mapping to zero address
+	 */
+	ret2 = mremap(ptr, size, 2 * page_size, MREMAP_MAYMOVE | MREMAP_FIXED,
+			0);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else {
+		assert(ret2 == 0);
+		clean_single_address(ret2, 2 * page_size);
+	}
+	clean_single_address(ptr, size);
+}
+
+void test_seal_mremap_move_dontunmap(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	void *newAddr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	// mremap to move, and don't unmap src addr.
+	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP, 0);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else {
+		assert(ret2 != MAP_FAILED);
+		clean_single_address(ret2, size);
+	}
+
+	clean_single_address(ptr, page_size);
+}
+
+void test_seal_mremap_move_dontunmap_anyaddr(bool seal)
+{
+	LOG_TEST_ENTER();
+	void *ptr;
+	void *newAddr;
+	unsigned long page_size = getpagesize();
+	unsigned long size = 4 * page_size;
+	int ret;
+	void *ret2;
+
+	setup_single_address(size, &ptr);
+
+	if (seal) {
+		ret = sys_mseal(ptr, size, MM_SEAL_MREMAP);
+		assert(!ret);
+	}
+
+	/*
+	 * The 0xdeaddead should not have effect on dest addr
+	 * when MREMAP_DONTUNMAP is set.
+	 */
+	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP,
+			0xdeaddead);
+	if (seal) {
+		assert(ret2 == MAP_FAILED);
+		assert(errno == EACCES);
+	} else {
+		assert(ret2 != MAP_FAILED);
+		assert((long)ret2 != 0xdeaddead);
+		clean_single_address(ret2, size);
+	}
+
+	clean_single_address(ptr, page_size);
+}
+
+int main(int argc, char **argv)
+{
+	test_seal_invalid_input();
+	test_seal_addseals();
+	test_seal_addseals_combined();
+	test_seal_addseals_reject();
+	test_seal_unmapped_start();
+	test_seal_unmapped_middle();
+	test_seal_unmapped_end();
+	test_seal_multiple_vmas();
+	test_seal_split_start();
+	test_seal_split_end();
+
+	test_seal_zero_length();
+	test_seal_twice();
+
+	test_seal_mprotect(false);
+	test_seal_mprotect(true);
+
+	test_seal_start_mprotect(false);
+	test_seal_start_mprotect(true);
+
+	test_seal_end_mprotect(false);
+	test_seal_end_mprotect(true);
+
+	test_seal_mprotect_unalign_len(false);
+	test_seal_mprotect_unalign_len(true);
+
+	test_seal_mprotect_unalign_len_variant_2(false);
+	test_seal_mprotect_unalign_len_variant_2(true);
+
+	test_seal_mprotect_two_vma(false);
+	test_seal_mprotect_two_vma(true);
+
+	test_seal_mprotect_two_vma_with_split(false);
+	test_seal_mprotect_two_vma_with_split(true);
+
+	test_seal_mprotect_partial_mprotect(false);
+	test_seal_mprotect_partial_mprotect(true);
+
+	test_seal_mprotect_two_vma_with_gap(false);
+	test_seal_mprotect_two_vma_with_gap(true);
+
+	test_seal_mprotect_merge(false);
+	test_seal_mprotect_merge(true);
+
+	test_seal_mprotect_split(false);
+	test_seal_mprotect_split(true);
+
+	test_seal_munmap(false);
+	test_seal_munmap(true);
+	test_seal_munmap_two_vma(false);
+	test_seal_munmap_two_vma(true);
+	test_seal_munmap_vma_with_gap(false);
+	test_seal_munmap_vma_with_gap(true);
+
+	test_munmap_start_freed(false);
+	test_munmap_start_freed(true);
+	test_munmap_middle_freed(false);
+	test_munmap_middle_freed(true);
+	test_munmap_end_freed(false);
+	test_munmap_end_freed(true);
+
+	test_seal_mremap_shrink(false);
+	test_seal_mremap_shrink(true);
+	test_seal_mremap_expand(false);
+	test_seal_mremap_expand(true);
+	test_seal_mremap_move(false);
+	test_seal_mremap_move(true);
+
+	test_seal_mremap_shrink_fixed(false);
+	test_seal_mremap_shrink_fixed(true);
+	test_seal_mremap_expand_fixed(false);
+	test_seal_mremap_expand_fixed(true);
+	test_seal_mremap_move_fixed(false);
+	test_seal_mremap_move_fixed(true);
+	test_seal_mremap_move_dontunmap(false);
+	test_seal_mremap_move_dontunmap(true);
+	test_seal_mremap_move_fixed_zero(false);
+	test_seal_mremap_move_fixed_zero(true);
+	test_seal_mremap_move_dontunmap_anyaddr(false);
+	test_seal_mremap_move_dontunmap_anyaddr(true);
+
+	test_seal_mmap_overwrite_prot(false);
+	test_seal_mmap_overwrite_prot(true);
+
+	printf("OK\n");
+	return 0;
+}