Re: [RFC PATCH v2 8/8] selftest mm/mseal mprotect/munmap/mremap/mmap

From: Muhammad Usama Anjum
Date: Fri Oct 20 2023 - 10:24:34 EST


On 10/17/23 2:08 PM, jeffxu@xxxxxxxxxxxx wrote:
> From: Jeff Xu <jeffxu@xxxxxxxxxx>
>
> selftest for sealing mprotect/munmap/mremap/mmap
>
> Signed-off-by: Jeff Xu <jeffxu@xxxxxxxxxx>
> ---
> 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;
> +}

--
BR,
Muhammad Usama Anjum