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Message-ID: <f797fbde-ffb7-44b0-8af6-4ed2ec47eac1@arm.com>
Date: Thu, 2 May 2024 12:24:00 +0100
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Subject: Re: [PATCH v10 3/5] selftest mm/mseal memory sealing
Content-Language: en-GB
To: jeffxu@chromium.org, akpm@linux-foundation.org, keescook@chromium.org,
 jannh@google.com, sroettger@google.com, willy@infradead.org,
 gregkh@linuxfoundation.org, torvalds@linux-foundation.org,
 usama.anjum@collabora.com, corbet@lwn.net, Liam.Howlett@oracle.com,
 surenb@google.com, merimus@google.com, rdunlap@infradead.org
Cc: jeffxu@google.com, jorgelo@chromium.org, groeck@chromium.org,
 linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
 linux-mm@kvack.org, pedro.falcato@gmail.com, dave.hansen@intel.com,
 linux-hardening@vger.kernel.org, deraadt@openbsd.org
References: <20240415163527.626541-1-jeffxu@chromium.org>
 <20240415163527.626541-4-jeffxu@chromium.org>
From: Ryan Roberts <ryan.roberts@arm.com>
In-Reply-To: <20240415163527.626541-4-jeffxu@chromium.org>
Content-Type: text/plain; charset=UTF-8
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On 15/04/2024 17:35, jeffxu@chromium.org wrote:
> From: Jeff Xu <jeffxu@chromium.org>
> 
> selftest for memory sealing change in mmap() and mseal().
> 
> Signed-off-by: Jeff Xu <jeffxu@chromium.org>
> ---
>  tools/testing/selftests/mm/.gitignore   |    1 +
>  tools/testing/selftests/mm/Makefile     |    1 +
>  tools/testing/selftests/mm/mseal_test.c | 1836 +++++++++++++++++++++++
>  3 files changed, 1838 insertions(+)
>  create mode 100644 tools/testing/selftests/mm/mseal_test.c
> 
> diff --git a/tools/testing/selftests/mm/.gitignore b/tools/testing/selftests/mm/.gitignore
> index d26e962f2ac4..98eaa4590f11 100644
> --- a/tools/testing/selftests/mm/.gitignore
> +++ b/tools/testing/selftests/mm/.gitignore
> @@ -47,3 +47,4 @@ mkdirty
>  va_high_addr_switch
>  hugetlb_fault_after_madv
>  hugetlb_madv_vs_map
> +mseal_test
> diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
> index eb5f39a2668b..95d10fe1b3c1 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 += pagemap_ioctl
>  TEST_GEN_FILES += thuge-gen
> diff --git a/tools/testing/selftests/mm/mseal_test.c b/tools/testing/selftests/mm/mseal_test.c
> new file mode 100644
> index 000000000000..06c780d1d8e5
> --- /dev/null
> +++ b/tools/testing/selftests/mm/mseal_test.c
> @@ -0,0 +1,1836 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <sys/mman.h>

I'm afraid this is causing a build error on our CI, and as a result we are not
running any mm selftests currently.

The error is here:

  CC       mseal_test
mseal_test.c: In function ‘test_seal_mremap_move_dontunmap’:
mseal_test.c:1469:50: error: ‘MREMAP_DONTUNMAP’ undeclared (first use in this
function)
 1469 |  ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP, 0);
      |                                                  ^~~~~~~~~~~~~~~~
mseal_test.c:1469:50: note: each undeclared identifier is reported only once for
each function it appears in
mseal_test.c: In function ‘test_seal_mremap_move_dontunmap_anyaddr’:
mseal_test.c:1501:50: error: ‘MREMAP_DONTUNMAP’ undeclared (first use in this
function)
 1501 |  ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP,
      |                                                  ^~~~~~~~~~~~~~~~


And I think the reason is due to our CI's toolchain's sys/mman.h not including
linux/mman.h where MREMAP_DONTUNMAP is defined.

I think the fix is to explicitly #include <linux/mman.h>, as a number of other
mm selftests do.

I'm not sure if this is still in mm-unstable? If so, it would good to remove it
so we can resume our testing.

> +#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>
> +#include <fcntl.h>
> +#include <assert.h>
> +#include <sys/ioctl.h>
> +#include <sys/vfs.h>
> +#include <sys/stat.h>
> +
> +/*
> + * need those definition for manually build using gcc.
> + * gcc -I ../../../../usr/include   -DDEBUG -O3  -DDEBUG -O3 mseal_test.c -o mseal_test
> + */
> +#ifndef PKEY_DISABLE_ACCESS
> +# define PKEY_DISABLE_ACCESS    0x1
> +#endif

If you pull in linux/mman.h directly, you shouldn't need this define as it will
be pulled in.

> +
> +#ifndef PKEY_DISABLE_WRITE
> +# define PKEY_DISABLE_WRITE     0x2
> +#endif

And this one.

> +
> +#ifndef PKEY_BITS_PER_KEY

bug: I think you missed the 'P' in PKEY?

> +#define PKEY_BITS_PER_PKEY      2
> +#endif

If you #include "pkey-helpers.h" you should get this define.

> +
> +#ifndef PKEY_MASK
> +#define PKEY_MASK       (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)
> +#endif

And you can use the PKEY_ACCESS_MASK macro that will be pulled in to avoid this
define too.

Thanks,
Ryan

> +
> +#define FAIL_TEST_IF_FALSE(c) do {\
> +		if (!(c)) {\
> +			ksft_test_result_fail("%s, line:%d\n", __func__, __LINE__);\
> +			goto test_end;\
> +		} \
> +	} \
> +	while (0)
> +
> +#define SKIP_TEST_IF_FALSE(c) do {\
> +		if (!(c)) {\
> +			ksft_test_result_skip("%s, line:%d\n", __func__, __LINE__);\
> +			goto test_end;\
> +		} \
> +	} \
> +	while (0)
> +
> +
> +#define TEST_END_CHECK() {\
> +		ksft_test_result_pass("%s\n", __func__);\
> +		return;\
> +test_end:\
> +		return;\
> +}
> +
> +#ifndef u64
> +#define u64 unsigned long long
> +#endif
> +
> +static unsigned long get_vma_size(void *addr, int *prot)
> +{
> +	FILE *maps;
> +	char line[256];
> +	int size = 0;
> +	uintptr_t  addr_start, addr_end;
> +	char protstr[5];
> +	*prot = 0;
> +
> +	maps = fopen("/proc/self/maps", "r");
> +	if (!maps)
> +		return 0;
> +
> +	while (fgets(line, sizeof(line), maps)) {
> +		if (sscanf(line, "%lx-%lx %4s", &addr_start, &addr_end, &protstr) == 3) {
> +			if (addr_start == (uintptr_t) addr) {
> +				size = addr_end - addr_start;
> +				if (protstr[0] == 'r')
> +					*prot |= 0x4;
> +				if (protstr[1] == 'w')
> +					*prot |= 0x2;
> +				if (protstr[2] == 'x')
> +					*prot |= 0x1;
> +				break;
> +			}
> +		}
> +	}
> +	fclose(maps);
> +	return size;
> +}
> +
> +/*
> + * define sys_xyx to call syscall directly.
> + */
> +static int sys_mseal(void *start, size_t len)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(__NR_mseal, start, len, 0);
> +	return sret;
> +}
> +
> +static int sys_mprotect(void *ptr, size_t size, unsigned long prot)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(__NR_mprotect, ptr, size, prot);
> +	return sret;
> +}
> +
> +static int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
> +		unsigned long pkey)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(__NR_pkey_mprotect, ptr, size, orig_prot, pkey);
> +	return sret;
> +}
> +
> +static void *sys_mmap(void *addr, unsigned long len, unsigned long prot,
> +	unsigned long flags, unsigned long fd, unsigned long offset)
> +{
> +	void *sret;
> +
> +	errno = 0;
> +	sret = (void *) syscall(__NR_mmap, addr, len, prot,
> +		flags, fd, offset);
> +	return sret;
> +}
> +
> +static int sys_munmap(void *ptr, size_t size)
> +{
> +	int sret;
> +
> +	errno = 0;
> +	sret = syscall(__NR_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;
> +}
> +
> +static int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
> +{
> +	int ret = syscall(__NR_pkey_alloc, flags, init_val);
> +
> +	return ret;
> +}
> +
> +static unsigned int __read_pkey_reg(void)
> +{
> +	unsigned int pkey_reg = 0;
> +#if defined(__i386__) || defined(__x86_64__) /* arch */
> +	unsigned int eax, edx;
> +	unsigned int ecx = 0;
> +
> +	asm volatile(".byte 0x0f,0x01,0xee\n\t"
> +			: "=a" (eax), "=d" (edx)
> +			: "c" (ecx));
> +	pkey_reg = eax;
> +#endif
> +	return pkey_reg;
> +}
> +
> +static void __write_pkey_reg(u64 pkey_reg)
> +{
> +#if defined(__i386__) || defined(__x86_64__) /* arch */
> +	unsigned int eax = pkey_reg;
> +	unsigned int ecx = 0;
> +	unsigned int edx = 0;
> +
> +	asm volatile(".byte 0x0f,0x01,0xef\n\t"
> +			: : "a" (eax), "c" (ecx), "d" (edx));
> +	assert(pkey_reg == __read_pkey_reg());
> +#endif
> +}
> +
> +static unsigned long pkey_bit_position(int pkey)
> +{
> +	return pkey * PKEY_BITS_PER_PKEY;
> +}
> +
> +static u64 set_pkey_bits(u64 reg, int pkey, u64 flags)
> +{
> +	unsigned long shift = pkey_bit_position(pkey);
> +
> +	/* mask out bits from pkey in old value */
> +	reg &= ~((u64)PKEY_MASK << shift);
> +	/* OR in new bits for pkey */
> +	reg |= (flags & PKEY_MASK) << shift;
> +	return reg;
> +}
> +
> +static void set_pkey(int pkey, unsigned long pkey_value)
> +{
> +	unsigned long mask = (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE);
> +	u64 new_pkey_reg;
> +
> +	assert(!(pkey_value & ~mask));
> +	new_pkey_reg = set_pkey_bits(__read_pkey_reg(), pkey, pkey_value);
> +	__write_pkey_reg(new_pkey_reg);
> +}
> +
> +static void setup_single_address(int size, void **ptrOut)
> +{
> +	void *ptr;
> +
> +	ptr = sys_mmap(NULL, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> +	assert(ptr != (void *)-1);
> +	*ptrOut = ptr;
> +}
> +
> +static void setup_single_address_rw(int size, void **ptrOut)
> +{
> +	void *ptr;
> +	unsigned long mapflags = MAP_ANONYMOUS | MAP_PRIVATE;
> +
> +	ptr = sys_mmap(NULL, size, PROT_READ | PROT_WRITE, mapflags, -1, 0);
> +	assert(ptr != (void *)-1);
> +	*ptrOut = ptr;
> +}
> +
> +static void clean_single_address(void *ptr, int size)
> +{
> +	int ret;
> +
> +	ret = munmap(ptr, size);
> +	assert(!ret);
> +}
> +
> +static void seal_single_address(void *ptr, int size)
> +{
> +	int ret;
> +
> +	ret = sys_mseal(ptr, size);
> +	assert(!ret);
> +}
> +
> +bool seal_support(void)
> +{
> +	int ret;
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +
> +	ptr = sys_mmap(NULL, page_size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> +	if (ptr == (void *) -1)
> +		return false;
> +
> +	ret = sys_mseal(ptr, page_size);
> +	if (ret < 0)
> +		return false;
> +
> +	return true;
> +}
> +
> +bool pkey_supported(void)
> +{
> +#if defined(__i386__) || defined(__x86_64__) /* arch */
> +	int pkey = sys_pkey_alloc(0, 0);
> +
> +	if (pkey > 0)
> +		return true;
> +#endif
> +	return false;
> +}
> +
> +static void test_seal_addseal(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_unmapped_start(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* mprotect will fail because 2 pages from ptr are unmapped. */
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* mseal will fail because 2 pages from ptr are unmapped. */
> +	ret = sys_mseal(ptr, size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	ret = sys_mseal(ptr + 2 * page_size, 2 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_unmapped_middle(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* mprotect will fail, since middle 2 pages are unmapped. */
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* mseal will fail as well. */
> +	ret = sys_mseal(ptr, size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* we still can add seal to the first page and last page*/
> +	ret = sys_mseal(ptr, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_mseal(ptr + 3 * page_size, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_unmapped_end(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* mprotect will fail since last 2 pages are unmapped. */
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* mseal will fail as well. */
> +	ret = sys_mseal(ptr, size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* The first 2 pages is not sealed, and can add seals */
> +	ret = sys_mseal(ptr, 2 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_multiple_vmas(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* mprotect will get applied to all 4 pages - 3 VMAs. */
> +	ret = sys_mprotect(ptr, size, PROT_READ);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* use mprotect to split the vma into 3. */
> +	ret = sys_mprotect(ptr + page_size, 2 * page_size,
> +			PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* mseal get applied to all 4 pages - 3 VMAs. */
> +	ret = sys_mseal(ptr, size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_split_start(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal the first page, this will split the VMA */
> +	ret = sys_mseal(ptr, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* add seal to the remain 3 pages */
> +	ret = sys_mseal(ptr + page_size, 3 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_split_end(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal the last page */
> +	ret = sys_mseal(ptr + 3 * page_size, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* Adding seals to the first 3 pages */
> +	ret = sys_mseal(ptr, 3 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_invalid_input(void)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(8 * page_size, &ptr);
> +	clean_single_address(ptr + 4 * page_size, 4 * page_size);
> +
> +	/* invalid flag */
> +	ret = syscall(__NR_mseal, ptr, size, 0x20);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* unaligned address */
> +	ret = sys_mseal(ptr + 1, 2 * page_size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* length too big */
> +	ret = sys_mseal(ptr, 5 * page_size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* length overflow */
> +	ret = sys_mseal(ptr, UINT64_MAX/page_size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* start is not in a valid VMA */
> +	ret = sys_mseal(ptr - page_size, 5 * page_size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_zero_length(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal 0 length will be OK, same as mprotect */
> +	ret = sys_mseal(ptr, 0);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* verify the 4 pages are not sealed by previous call. */
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_zero_address(void)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	int prot;
> +
> +	/* use mmap to change protection. */
> +	ptr = sys_mmap(0, size, PROT_NONE,
> +			MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> +	FAIL_TEST_IF_FALSE(ptr == 0);
> +
> +	size = get_vma_size(ptr, &prot);
> +	FAIL_TEST_IF_FALSE(size == 4 * page_size);
> +
> +	ret = sys_mseal(ptr, size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* verify the 4 pages are sealed by previous call. */
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_twice(void)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* apply the same seal will be OK. idempotent. */
> +	ret = sys_mseal(ptr, size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_single_address(ptr, size);
> +
> +	ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_start_mprotect(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_single_address(ptr, page_size);
> +
> +	/* the first page is sealed. */
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* pages after the first page is not sealed. */
> +	ret = sys_mprotect(ptr + page_size, page_size * 3,
> +			PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_end_mprotect(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_single_address(ptr + page_size, 3 * page_size);
> +
> +	/* first page is not sealed */
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* last 3 page are sealed */
> +	ret = sys_mprotect(ptr + page_size, page_size * 3,
> +			PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_unalign_len(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_single_address(ptr, page_size * 2 - 1);
> +
> +	/* 2 pages are sealed. */
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_mprotect(ptr + page_size * 2, page_size,
> +			PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_unalign_len_variant_2(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +	if (seal)
> +		seal_single_address(ptr, page_size * 2 + 1);
> +
> +	/* 3 pages are sealed. */
> +	ret = sys_mprotect(ptr, page_size * 3, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_mprotect(ptr + page_size * 3, page_size,
> +			PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_two_vma(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	if (seal)
> +		seal_single_address(ptr, page_size * 4);
> +
> +	ret = sys_mprotect(ptr, page_size * 2, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_mprotect(ptr + page_size * 2, page_size * 2,
> +			PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_two_vma_with_split(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* mseal can apply across 2 vma, also split them. */
> +	if (seal)
> +		seal_single_address(ptr + page_size, page_size * 2);
> +
> +	/* the first page is not sealed. */
> +	ret = sys_mprotect(ptr, page_size, PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* the second page is sealed. */
> +	ret = sys_mprotect(ptr + page_size, page_size, PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* the third page is sealed. */
> +	ret = sys_mprotect(ptr + 2 * page_size, page_size,
> +			PROT_READ | PROT_WRITE);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* the fouth page is not sealed. */
> +	ret = sys_mprotect(ptr + 3 * page_size, page_size,
> +			PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_partial_mprotect(bool seal)
> +{
> +	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_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)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_two_vma_with_gap(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* use mprotect to split. */
> +	ret = sys_mprotect(ptr + 3 * page_size, page_size,
> +			PROT_READ | PROT_WRITE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* use munmap to free two pages in the middle */
> +	ret = sys_munmap(ptr + page_size, 2 * page_size);
> +	FAIL_TEST_IF_FALSE(!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);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* mseal will fail as well. */
> +	ret = sys_mseal(ptr, 4 * page_size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* the first page is not sealed. */
> +	ret = sys_mprotect(ptr, page_size, PROT_READ);
> +	FAIL_TEST_IF_FALSE(ret == 0);
> +
> +	/* the last page is not sealed. */
> +	ret = sys_mprotect(ptr + 3 * page_size, page_size, PROT_READ);
> +	FAIL_TEST_IF_FALSE(ret == 0);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_split(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal all 4 pages. */
> +	if (seal) {
> +		ret = sys_mseal(ptr, 4 * page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* mprotect is sealed. */
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +
> +	ret = sys_mprotect(ptr + 2 * page_size, 2 * page_size, PROT_READ);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mprotect_merge(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal first two pages. */
> +	if (seal) {
> +		ret = sys_mseal(ptr, 2 * page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* 2 pages are sealed. */
> +	ret = sys_mprotect(ptr, 2 * page_size, PROT_READ);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* last 2 pages are not sealed. */
> +	ret = sys_mprotect(ptr + 2 * page_size, 2 * page_size, PROT_READ);
> +	FAIL_TEST_IF_FALSE(ret == 0);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_munmap(bool seal)
> +{
> +	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);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* 4 pages are sealed. */
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +/*
> + * 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)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	ret = sys_munmap(ptr, page_size * 2);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_munmap(ptr + page_size, page_size * 2);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +/*
> + * allocate a VMA with 4 pages.
> + * munmap the middle 2 pages.
> + * seal the whole 4 pages, will fail.
> + * munmap the first page will be OK.
> + * munmap the last page will be OK.
> + */
> +static void test_seal_munmap_vma_with_gap(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	if (seal) {
> +		/* can't have gap in the middle. */
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	}
> +
> +	ret = sys_munmap(ptr, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_munmap(ptr + page_size * 2, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_munmap(ptr, size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_munmap_start_freed(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	int prot;
> +
> +	setup_single_address(size, &ptr);
> +
> +	/* unmap the first page. */
> +	ret = sys_munmap(ptr, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal the last 3 pages. */
> +	if (seal) {
> +		ret = sys_mseal(ptr + page_size, 3 * page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* unmap from the first page. */
> +	ret = sys_munmap(ptr, size);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +
> +		size = get_vma_size(ptr + page_size, &prot);
> +		FAIL_TEST_IF_FALSE(size == page_size * 3);
> +	} else {
> +		/* note: this will be OK, even the first page is */
> +		/* already unmapped. */
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +		size = get_vma_size(ptr + page_size, &prot);
> +		FAIL_TEST_IF_FALSE(size == 0);
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_munmap_end_freed(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal the first 3 pages. */
> +	if (seal) {
> +		ret = sys_mseal(ptr, 3 * page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* unmap all pages. */
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_munmap_middle_freed(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	int prot;
> +
> +	setup_single_address(size, &ptr);
> +	/* unmap 2 pages in the middle. */
> +	ret = sys_munmap(ptr + page_size, page_size * 2);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* seal the first page. */
> +	if (seal) {
> +		ret = sys_mseal(ptr, page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* munmap all 4 pages. */
> +	ret = sys_munmap(ptr, size);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +
> +		size = get_vma_size(ptr, &prot);
> +		FAIL_TEST_IF_FALSE(size == page_size);
> +
> +		size = get_vma_size(ptr + page_size * 3, &prot);
> +		FAIL_TEST_IF_FALSE(size == page_size);
> +	} else {
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +		size = get_vma_size(ptr, &prot);
> +		FAIL_TEST_IF_FALSE(size == 0);
> +
> +		size = get_vma_size(ptr + page_size * 3, &prot);
> +		FAIL_TEST_IF_FALSE(size == 0);
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_shrink(bool seal)
> +{
> +	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);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* shrink from 4 pages to 2 pages. */
> +	ret2 = mremap(ptr, size, 2 * page_size, 0, 0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else {
> +		FAIL_TEST_IF_FALSE(ret2 != MAP_FAILED);
> +
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_expand(bool seal)
> +{
> +	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);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, 2 * page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* expand from 2 page to 4 pages. */
> +	ret2 = mremap(ptr, 2 * page_size, 4 * page_size, 0, 0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else {
> +		FAIL_TEST_IF_FALSE(ret2 == ptr);
> +
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_move(bool seal)
> +{
> +	void *ptr, *newPtr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +	setup_single_address(size, &newPtr);
> +	clean_single_address(newPtr, size);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* move from ptr to fixed address. */
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_FIXED, newPtr);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else {
> +		FAIL_TEST_IF_FALSE(ret2 != MAP_FAILED);
> +
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mmap_overwrite_prot(bool seal)
> +{
> +	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);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* use mmap to change protection. */
> +	ret2 = sys_mmap(ptr, size, PROT_NONE,
> +			MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else
> +		FAIL_TEST_IF_FALSE(ret2 == ptr);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mmap_expand(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 12 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +	/* ummap last 4 pages. */
> +	ret = sys_munmap(ptr + 8 * page_size, 4 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, 8 * page_size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* use mmap to expand. */
> +	ret2 = sys_mmap(ptr, size, PROT_READ,
> +			MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else
> +		FAIL_TEST_IF_FALSE(ret2 == ptr);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mmap_shrink(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 12 * page_size;
> +	int ret;
> +	void *ret2;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* use mmap to shrink. */
> +	ret2 = sys_mmap(ptr, 8 * page_size, PROT_READ,
> +			MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else
> +		FAIL_TEST_IF_FALSE(ret2 == ptr);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_shrink_fixed(bool seal)
> +{
> +	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_address(size, &newAddr);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* mremap to move and shrink to fixed address */
> +	ret2 = mremap(ptr, size, 2 * page_size, MREMAP_MAYMOVE | MREMAP_FIXED,
> +			newAddr);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else
> +		FAIL_TEST_IF_FALSE(ret2 == newAddr);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_expand_fixed(bool seal)
> +{
> +	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_address(size, &newAddr);
> +
> +	if (seal) {
> +		ret = sys_mseal(newAddr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* mremap to move and expand to fixed address */
> +	ret2 = mremap(ptr, page_size, size, MREMAP_MAYMOVE | MREMAP_FIXED,
> +			newAddr);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else
> +		FAIL_TEST_IF_FALSE(ret2 == newAddr);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_move_fixed(bool seal)
> +{
> +	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_address(size, &newAddr);
> +
> +	if (seal) {
> +		ret = sys_mseal(newAddr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* mremap to move to fixed address */
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_FIXED, newAddr);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else
> +		FAIL_TEST_IF_FALSE(ret2 == newAddr);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_move_fixed_zero(bool seal)
> +{
> +	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);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/*
> +	 * MREMAP_FIXED can move the mapping to zero address
> +	 */
> +	ret2 = mremap(ptr, size, 2 * page_size, MREMAP_MAYMOVE | MREMAP_FIXED,
> +			0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else {
> +		FAIL_TEST_IF_FALSE(ret2 == 0);
> +
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_move_dontunmap(bool seal)
> +{
> +	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);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* mremap to move, and don't unmap src addr. */
> +	ret2 = mremap(ptr, size, size, MREMAP_MAYMOVE | MREMAP_DONTUNMAP, 0);
> +	if (seal) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else {
> +		FAIL_TEST_IF_FALSE(ret2 != MAP_FAILED);
> +
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_mremap_move_dontunmap_anyaddr(bool seal)
> +{
> +	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);
> +		FAIL_TEST_IF_FALSE(!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) {
> +		FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> +		FAIL_TEST_IF_FALSE(errno == EPERM);
> +	} else {
> +		FAIL_TEST_IF_FALSE(ret2 != MAP_FAILED);
> +		FAIL_TEST_IF_FALSE((long)ret2 != 0xdeaddead);
> +
> +	}
> +
> +	TEST_END_CHECK();
> +}
> +
> +
> +static void test_seal_merge_and_split(void)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size;
> +	int ret;
> +	int prot;
> +
> +	/* (24 RO) */
> +	setup_single_address(24 * page_size, &ptr);
> +
> +	/* use mprotect(NONE) to set out boundary */
> +	/* (1 NONE) (22 RO) (1 NONE) */
> +	ret = sys_mprotect(ptr, page_size, PROT_NONE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	ret = sys_mprotect(ptr + 23 * page_size, page_size, PROT_NONE);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr + page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size == 22 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 4);
> +
> +	/* use mseal to split from beginning */
> +	/* (1 NONE) (1 RO_SEAL) (21 RO) (1 NONE) */
> +	ret = sys_mseal(ptr + page_size, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr + page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size == page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +	size = get_vma_size(ptr + 2 * page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size == 21 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +
> +	/* use mseal to split from the end. */
> +	/* (1 NONE) (1 RO_SEAL) (20 RO) (1 RO_SEAL) (1 NONE) */
> +	ret = sys_mseal(ptr + 22 * page_size, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr + 22 * page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size == page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +	size = get_vma_size(ptr + 2 * page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size == 20 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +
> +	/* merge with prev. */
> +	/* (1 NONE) (2 RO_SEAL) (19 RO) (1 RO_SEAL) (1 NONE) */
> +	ret = sys_mseal(ptr + 2 * page_size, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr +  page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size ==  2 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +
> +	/* merge with after. */
> +	/* (1 NONE) (2 RO_SEAL) (18 RO) (2 RO_SEALS) (1 NONE) */
> +	ret = sys_mseal(ptr + 21 * page_size, page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr +  21 * page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size ==  2 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +
> +	/* split and merge from prev */
> +	/* (1 NONE) (3 RO_SEAL) (17 RO) (2 RO_SEALS) (1 NONE) */
> +	ret = sys_mseal(ptr + 2 * page_size, 2 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr +  1 * page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size ==  3 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +	ret = sys_munmap(ptr + page_size,  page_size);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +	ret = sys_mprotect(ptr + 2 * page_size, page_size,  PROT_NONE);
> +	FAIL_TEST_IF_FALSE(ret < 0);
> +
> +	/* split and merge from next */
> +	/* (1 NONE) (3 RO_SEAL) (16 RO) (3 RO_SEALS) (1 NONE) */
> +	ret = sys_mseal(ptr + 20 * page_size, 2 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +	size = get_vma_size(ptr +  20 * page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size ==  3 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +
> +	/* merge from middle of prev and middle of next. */
> +	/* (1 NONE) (22 RO_SEAL) (1 NONE) */
> +	ret = sys_mseal(ptr + 2 * page_size, 20 * page_size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +	size = get_vma_size(ptr +  page_size, &prot);
> +	FAIL_TEST_IF_FALSE(size ==  22 * page_size);
> +	FAIL_TEST_IF_FALSE(prot == 0x4);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_discard_ro_anon_on_rw(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address_rw(size, &ptr);
> +	FAIL_TEST_IF_FALSE(ptr != (void *)-1);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* sealing doesn't take effect on RW memory. */
> +	ret = sys_madvise(ptr, size, MADV_DONTNEED);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* base seal still apply. */
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_discard_ro_anon_on_pkey(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	int pkey;
> +
> +	SKIP_TEST_IF_FALSE(pkey_supported());
> +
> +	setup_single_address_rw(size, &ptr);
> +	FAIL_TEST_IF_FALSE(ptr != (void *)-1);
> +
> +	pkey = sys_pkey_alloc(0, 0);
> +	FAIL_TEST_IF_FALSE(pkey > 0);
> +
> +	ret = sys_mprotect_pkey((void *)ptr, size, PROT_READ | PROT_WRITE, pkey);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* sealing doesn't take effect if PKRU allow write. */
> +	set_pkey(pkey, 0);
> +	ret = sys_madvise(ptr, size, MADV_DONTNEED);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* sealing will take effect if PKRU deny write. */
> +	set_pkey(pkey, PKEY_DISABLE_WRITE);
> +	ret = sys_madvise(ptr, size, MADV_DONTNEED);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	/* base seal still apply. */
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_discard_ro_anon_on_filebacked(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	int fd;
> +	unsigned long mapflags = MAP_PRIVATE;
> +
> +	fd = memfd_create("test", 0);
> +	FAIL_TEST_IF_FALSE(fd > 0);
> +
> +	ret = fallocate(fd, 0, 0, size);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	ptr = sys_mmap(NULL, size, PROT_READ, mapflags, fd, 0);
> +	FAIL_TEST_IF_FALSE(ptr != MAP_FAILED);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* sealing doesn't apply for file backed mapping. */
> +	ret = sys_madvise(ptr, size, MADV_DONTNEED);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +	close(fd);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_discard_ro_anon_on_shared(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +	unsigned long mapflags = MAP_ANONYMOUS | MAP_SHARED;
> +
> +	ptr = sys_mmap(NULL, size, PROT_READ, mapflags, -1, 0);
> +	FAIL_TEST_IF_FALSE(ptr != (void *)-1);
> +
> +	if (seal) {
> +		ret = sys_mseal(ptr, size);
> +		FAIL_TEST_IF_FALSE(!ret);
> +	}
> +
> +	/* sealing doesn't apply for shared mapping. */
> +	ret = sys_madvise(ptr, size, MADV_DONTNEED);
> +	FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +static void test_seal_discard_ro_anon(bool seal)
> +{
> +	void *ptr;
> +	unsigned long page_size = getpagesize();
> +	unsigned long size = 4 * page_size;
> +	int ret;
> +
> +	setup_single_address(size, &ptr);
> +
> +	if (seal)
> +		seal_single_address(ptr, size);
> +
> +	ret = sys_madvise(ptr, size, MADV_DONTNEED);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	ret = sys_munmap(ptr, size);
> +	if (seal)
> +		FAIL_TEST_IF_FALSE(ret < 0);
> +	else
> +		FAIL_TEST_IF_FALSE(!ret);
> +
> +	TEST_END_CHECK();
> +}
> +
> +int main(int argc, char **argv)
> +{
> +	bool test_seal = seal_support();
> +
> +	ksft_print_header();
> +
> +	if (!test_seal)
> +		ksft_exit_skip("sealing not supported, check CONFIG_64BIT\n");
> +
> +	if (!pkey_supported())
> +		ksft_print_msg("PKEY not supported\n");
> +
> +	ksft_set_plan(80);
> +
> +	test_seal_addseal();
> +	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_invalid_input();
> +	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_discard_ro_anon(false);
> +	test_seal_discard_ro_anon(true);
> +	test_seal_discard_ro_anon_on_rw(false);
> +	test_seal_discard_ro_anon_on_rw(true);
> +	test_seal_discard_ro_anon_on_shared(false);
> +	test_seal_discard_ro_anon_on_shared(true);
> +	test_seal_discard_ro_anon_on_filebacked(false);
> +	test_seal_discard_ro_anon_on_filebacked(true);
> +	test_seal_mmap_overwrite_prot(false);
> +	test_seal_mmap_overwrite_prot(true);
> +	test_seal_mmap_expand(false);
> +	test_seal_mmap_expand(true);
> +	test_seal_mmap_shrink(false);
> +	test_seal_mmap_shrink(true);
> +
> +	test_seal_merge_and_split();
> +	test_seal_zero_address();
> +
> +	test_seal_discard_ro_anon_on_pkey(false);
> +	test_seal_discard_ro_anon_on_pkey(true);
> +
> +	ksft_finished();
> +	return 0;
> +}