[PATCH v1 6/6] PKEY:selftest pkey_enforce_api for munmap

From: jeffxu
Date: Thu May 18 2023 - 21:19:51 EST


From: Jeff Xu <jeffxu@xxxxxxxxxx>

Add selftest for pkey_enforce_api for mprotect

Signed-off-by: Jeff Xu<jeffxu@xxxxxxxxxx>
---
tools/testing/selftests/mm/pkey_enforce_api.c | 437 ++++++++++++++++++
1 file changed, 437 insertions(+)

diff --git a/tools/testing/selftests/mm/pkey_enforce_api.c b/tools/testing/selftests/mm/pkey_enforce_api.c
index 23663c89bc9c..92aa29248e1f 100644
--- a/tools/testing/selftests/mm/pkey_enforce_api.c
+++ b/tools/testing/selftests/mm/pkey_enforce_api.c
@@ -833,6 +833,429 @@ void test_mprotect_child_thread(bool enforce)
clean_single_address_with_pkey(pkey, ptr, size);
}

+// mmap one address with one page.
+// assign PKEY to the address.
+// munmap on the address is protected.
+void test_munmap_single_address(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_single_address_with_pkey(enforce, size, &pkey, &ptr);
+
+ // disable write access.
+ pkey_write_deny(pkey);
+
+ ret = munmap(ptr, size);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr, size);
+ assert(!ret);
+ }
+
+ clean_single_address_with_pkey(pkey, ptr, size);
+}
+
+// mmap two address (continuous two pages).
+// assign PKEY to them with one mprotect_pkey call (merged address).
+// munmap two address in one call (merged address).
+void test_munmap_two_address_merge(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ void *ptr2;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_two_continues_fixed_address_with_pkey(enforce, size, &pkey, &ptr,
+ &ptr2);
+
+ // disable write.
+ pkey_write_deny(pkey);
+
+ // munmap on both addresses with one call (merged).
+ ret = munmap(ptr, size * 2);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr, size * 2);
+ assert(!ret);
+ }
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap two address (continuous two pages).
+// assign PKEY to the second address.
+// munmap on the second address is protected.
+void test_munmap_two_address_deny_second(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ void *ptr2;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_two_continues_fixed_address_protect_second_with_pkey(
+ enforce, size, &pkey, &ptr, &ptr2);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ ret = munmap(ptr2, size);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ ret = munmap(ptr, size);
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr2, size);
+ assert(!ret);
+ }
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap two address (continuous two pages).
+// assign PKEY to the second address.
+// munmap on the range that includes the second address.
+void test_munmap_two_address_deny_range(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ void *ptr2;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_two_continues_fixed_address_protect_second_with_pkey(
+ enforce, size, &pkey, &ptr, &ptr2);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ ret = munmap(ptr, size * 2);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr, size * 2);
+ assert(!ret);
+ }
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap one address with 4 pages.
+// assign PKEY to the second page only.
+// munmap on memory range that includes the second pages is protected.
+void test_munmap_vma_middle_addr(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr, *ptr2, *ptr3;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr,
+ &ptr2, &ptr3);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ // munmap support merge, we are going to make sure we don't regress.
+ ret = munmap(addr1, size * 4);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr, size * 4);
+ assert(!ret);
+ }
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap one address with 4 pages.
+// assign PKEY to the second page only.
+// munmap from 2nd page.
+void test_munmap_shrink(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr, *ptr2, *ptr3;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr,
+ &ptr2, &ptr3);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ // munmap support merge, we are going to make sure we don't regress.
+ ret = munmap(ptr2, size * 3);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr2, size * 3);
+ assert(!ret);
+ }
+
+ ret = munmap(ptr, size);
+ assert(!ret);
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap one address with 4 pages.
+// assign PKEY to the second page only.
+// munmap from 2nd page but size is less than one page
+void test_munmap_unaligned(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr, *ptr2, *ptr3;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr,
+ &ptr2, &ptr3);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ // munmap support merge, we are going to make sure we don't regress.
+ ret = munmap(ptr2, size - 1);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr2, size - 1);
+ assert(!ret);
+ }
+
+ ret = munmap(ptr, size * 4);
+ assert(!ret);
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap one address with 4 pages.
+// assign PKEY to the second page only.
+// munmap from 2nd page but size is less than one page
+void test_munmap_unaligned2(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr, *ptr2, *ptr3;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr,
+ &ptr2, &ptr3);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ // munmap support merge, we are going to make sure we don't regress.
+ ret = munmap(ptr2, size + 1);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(ptr2, size + 1);
+ assert(!ret);
+ }
+
+ ret = munmap(ptr, size * 4);
+ assert(!ret);
+
+ ret = sys_pkey_free(pkey);
+ assert(ret == 0);
+}
+
+// mmap one address with one page.
+// assign PKEY to the address.
+// munmap on the address but with size of 4 pages(should OK).
+void test_munmap_outbound_addr(bool enforce)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_single_fixed_address_with_pkey(enforce, size, &pkey, &ptr);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ // Interesting enough, this is allowed, even the other 3 pages are not allocated.
+ ret = munmap(addr1, size * 4);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey);
+
+ if (enforce) {
+ ret = munmap(addr1, size * 4);
+ assert(!ret);
+ }
+
+ clean_single_address_with_pkey(pkey, ptr, size);
+}
+// mmap two addresses, with a page gap between two.
+// assign pkeys on both address.
+// disable access to the second address.
+// munmap from start of address1 to the end of address 2,
+// because there is a gap in the memory range, mprotect will fail.
+void test_munmap_gapped_address_with_two_pkeys(bool enforce)
+{
+ int pkey, pkey2;
+ int ret;
+ void *ptr, *ptr2;
+ int size = PAGE_SIZE;
+
+ LOG_TEST_ENTER(enforce);
+
+ setup_address_with_gap_two_pkeys(enforce, size, &pkey, &pkey2, &ptr,
+ &ptr2);
+
+ // disable write access.
+ pkey_write_deny(pkey2);
+
+ // Interesting enough, this is allowed, even there is a gap beween address 1 and 2.
+ ret = munmap(addr1, size * 3);
+ if (enforce)
+ assert(ret < 0);
+ else
+ assert(!ret);
+
+ pkey_write_allow(pkey2);
+ if (enforce) {
+ ret = munmap(addr1, size * 3);
+ assert(!ret);
+ }
+}
+
+// use write-deny pkey and see if program can exit properly.
+// This is manual test, run it at end if needed.
+void test_exit_munmap_disable_write(void)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ int size = PAGE_SIZE;
+
+ pkey = sys_pkey_alloc(PKEY_ENFORCE_API, 0);
+ assert(pkey > 0);
+
+ // allocate 1 page.
+ ptr = mmap(addr1, size, PROT_READ,
+ MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
+ assert(ptr == addr1);
+
+ // assign pkey to the first address.
+ ret = sys_mprotect_pkey(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC,
+ pkey);
+ assert(!ret);
+
+ // disable write through pkey.
+ pkey_write_deny(pkey);
+
+ ret = munmap(ptr, size);
+ assert(ret < 0);
+}
+
+// use disable-all pkey and see if program can exit properly.
+// This is manual test, run it at end if needed.
+void test_exit_munmap_disable_all(void)
+{
+ int pkey;
+ int ret;
+ void *ptr;
+ int size = PAGE_SIZE;
+
+ pkey = sys_pkey_alloc(PKEY_ENFORCE_API, 0);
+ assert(pkey > 0);
+
+ // allocate 1 page.
+ ptr = mmap(addr2, size, PROT_READ,
+ MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
+ assert(ptr == addr2);
+
+ // assign pkey to the first address.
+ ret = sys_mprotect_pkey(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC,
+ pkey);
+ assert(!ret);
+
+ // disable write through pkey.
+ pkey_access_deny(pkey);
+
+ ret = munmap(addr1, size);
+ assert(ret < 0);
+}
+
void test_enforce_api(void)
{
for (int i = 0; i < 2; i++) {
@@ -848,7 +1271,21 @@ void test_enforce_api(void)
test_mprotect_unaligned2(enforce);
test_mprotect_child_thread(enforce);
test_mprotect_gapped_address_with_two_pkeys(enforce);
+
+ test_munmap_single_address(enforce);
+ test_munmap_two_address_merge(enforce);
+ test_munmap_two_address_deny_second(enforce);
+ test_munmap_two_address_deny_range(enforce);
+ test_munmap_vma_middle_addr(enforce);
+ test_munmap_outbound_addr(enforce);
+ test_munmap_shrink(enforce);
+ test_munmap_unaligned(enforce);
+ test_munmap_unaligned2(enforce);
+ test_munmap_gapped_address_with_two_pkeys(enforce);
}
+
+ test_exit_munmap_disable_write();
+ test_exit_munmap_disable_all();
}

int main(void)
--
2.40.1.606.ga4b1b128d6-goog