From: Ackerley Tng <ackerleytng@xxxxxxxxxx>
Add some selftests for guest_memfd same-range validation, which check
that the slot userspace_addr covers the same range as the memory in
guest_memfd:
+ When slot->userspace_addr is set to 0, there should be no range
match validation on guest_memfd binding.
+ guest_memfd binding should fail if
+ slot->userspace_addr is not from guest_memfd
+ slot->userspace_addr is mmap()ed from some other file
+ slot->userspace_addr is mmap()ed from some other guest_memfd
+ slot->userspace_addr is mmap()ed from a different range in the
same guest_memfd
+ guest_memfd binding should succeed if slot->userspace_addr is
mmap()ed from the same range in the same guest_memfd provided in
slot->guest_memfd
Signed-off-by: Ackerley Tng <ackerleytng@xxxxxxxxxx>
Signed-off-by: Fuad Tabba <tabba@xxxxxxxxxx>
---
.../testing/selftests/kvm/guest_memfd_test.c | 168 ++++++++++++++++++
1 file changed, 168 insertions(+)
diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c
index 443c49185543..60aaba5808a5 100644
--- a/tools/testing/selftests/kvm/guest_memfd_test.c
+++ b/tools/testing/selftests/kvm/guest_memfd_test.c
@@ -197,6 +197,173 @@ static void test_create_guest_memfd_multiple(struct kvm_vm *vm)
close(fd1);
}
+#define GUEST_MEMFD_TEST_SLOT 10
+#define GUEST_MEMFD_TEST_GPA 0x100000000
+
+static void
+test_bind_guest_memfd_disabling_range_match_validation(struct kvm_vm *vm,
+ int fd)
+{
+ size_t page_size = getpagesize();
+ int ret;
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, page_size, 0,
+ fd, 0);
+ TEST_ASSERT(!ret,
+ "setting slot->userspace_addr to 0 should disable validation");
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, 0, 0,
+ fd, 0);
+ TEST_ASSERT(!ret, "Deleting memslot should work");
+}
+
+static void
+test_bind_guest_memfd_anon_memory_in_userspace_addr(struct kvm_vm *vm, int fd)
+{
+ size_t page_size = getpagesize();
+ void *userspace_addr;
+ int ret;
+
+ userspace_addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, page_size,
+ userspace_addr, fd, 0);
+ TEST_ASSERT(ret == -1,
+ "slot->userspace_addr is not from the guest_memfd and should fail");
+}
+
+static void test_bind_guest_memfd_shared_memory_other_file_in_userspace_addr(
+ struct kvm_vm *vm, int fd)
+{
+ size_t page_size = getpagesize();
+ void *userspace_addr;
+ int other_fd;
+ int ret;
+
+ other_fd = memfd_create("shared_memory_other_file", 0);
+ TEST_ASSERT(other_fd > 0, "Creating other file should succeed");
+
+ userspace_addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_SHARED, other_fd, 0);
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, page_size,
+ userspace_addr, fd, 0);
+ TEST_ASSERT(ret == -1,
+ "slot->userspace_addr is not from the guest_memfd and should fail");
+
+ TEST_ASSERT(!munmap(userspace_addr, page_size),
+ "munmap() to cleanup should succeed");
+
+ close(other_fd);
+}
+
+static void
+test_bind_guest_memfd_other_guest_memfd_in_userspace_addr(struct kvm_vm *vm,
+ int fd)
+{
+ size_t page_size = getpagesize();
+ void *userspace_addr;
+ int other_fd;
+ int ret;
+
+ other_fd = vm_create_guest_memfd(vm, page_size * 2,
+ GUEST_MEMFD_FLAG_SUPPORT_SHARED);
+ TEST_ASSERT(other_fd > 0, "Creating other file should succeed");
+
+ userspace_addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_SHARED, other_fd, 0);
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, page_size,
+ userspace_addr, fd, 0);
+ TEST_ASSERT(ret == -1,
+ "slot->userspace_addr is not from the guest_memfd and should fail");
+
+ TEST_ASSERT(!munmap(userspace_addr, page_size),
+ "munmap() to cleanup should succeed");
+
+ close(other_fd);
+}
+
+static void
+test_bind_guest_memfd_other_range_in_userspace_addr(struct kvm_vm *vm, int fd)
+{
+ size_t page_size = getpagesize();
+ void *userspace_addr;
+ int ret;
+
+ userspace_addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, page_size);
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, page_size,
+ userspace_addr, fd, 0);
+ TEST_ASSERT(ret == -1,
+ "slot->userspace_addr is not from the same range and should fail");
+
+ TEST_ASSERT(!munmap(userspace_addr, page_size),
+ "munmap() to cleanup should succeed");
+}
+
+static void
+test_bind_guest_memfd_same_range_in_userspace_addr(struct kvm_vm *vm, int fd)
+{
+ size_t page_size = getpagesize();
+ void *userspace_addr;
+ int ret;
+
+ userspace_addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, page_size);
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, page_size,
+ userspace_addr, fd, page_size);
+ TEST_ASSERT(!ret,
+ "slot->userspace_addr is the same range and should succeed");
+
+ TEST_ASSERT(!munmap(userspace_addr, page_size),
+ "munmap() to cleanup should succeed");
+
+ ret = __vm_set_user_memory_region2(vm, GUEST_MEMFD_TEST_SLOT,
+ KVM_MEM_GUEST_MEMFD,
+ GUEST_MEMFD_TEST_GPA, 0, 0,
+ fd, 0);
+ TEST_ASSERT(!ret, "Deleting memslot should work");
+}
+
+static void test_bind_guest_memfd_wrt_userspace_addr(struct kvm_vm *vm)
+{
+ size_t page_size = getpagesize();
+ int fd;
+
+ if (!vm_check_cap(vm, KVM_CAP_GUEST_MEMFD) ||
+ !vm_check_cap(vm, KVM_CAP_GMEM_SHARED_MEM))
+ return;
+
+ fd = vm_create_guest_memfd(vm, page_size * 2,
+ GUEST_MEMFD_FLAG_SUPPORT_SHARED);
+
+ test_bind_guest_memfd_disabling_range_match_validation(vm, fd);
+ test_bind_guest_memfd_anon_memory_in_userspace_addr(vm, fd);
+ test_bind_guest_memfd_shared_memory_other_file_in_userspace_addr(vm, fd);
+ test_bind_guest_memfd_other_guest_memfd_in_userspace_addr(vm, fd);
+ test_bind_guest_memfd_other_range_in_userspace_addr(vm, fd);
+ test_bind_guest_memfd_same_range_in_userspace_addr(vm, fd);
+
+ close(fd);
+}
+
static void test_with_type(unsigned long vm_type, uint64_t guest_memfd_flags,
bool expect_mmap_allowed)
{
@@ -214,6 +381,7 @@ static void test_with_type(unsigned long vm_type, uint64_t guest_memfd_flags,
vm = vm_create_barebones_type(vm_type);
test_create_guest_memfd_multiple(vm);
+ test_bind_guest_memfd_wrt_userspace_addr(vm);
test_create_guest_memfd_invalid_sizes(vm, guest_memfd_flags, page_size);
fd = vm_create_guest_memfd(vm, total_size, guest_memfd_flags);
--
2.49.0.1045.g170613ef41-goog
