[PATCH v3 3/5] selftests/landlock: Test ioctl with memfds

["Günther Noack" <gnoack@google.com>]

Because the ioctl right is associated with the opened file,
we expect that it will work with files which are opened by means
other than open(2).

Signed-off-by: Günther Noack <gnoack@google.com>
---
 tools/testing/selftests/landlock/fs_test.c | 50 +++++++++++++++-------
 1 file changed, 34 insertions(+), 16 deletions(-)

diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 456bd681091d..4eb989d5ff39 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -3716,22 +3716,6 @@ TEST_F_FORK(ftruncate, open_and_ftruncate_in_different_processes)
 	ASSERT_EQ(0, close(socket_fds[1]));
 }
 
-TEST(memfd_ftruncate)
-{
-	int fd;
-
-	fd = memfd_create("name", MFD_CLOEXEC);
-	ASSERT_LE(0, fd);
-
-	/*
-	 * Checks that ftruncate is permitted on file descriptors that are
-	 * created in ways other than open(2).
-	 */
-	EXPECT_EQ(0, test_ftruncate(fd));
-
-	ASSERT_EQ(0, close(fd));
-}
-
 /* Invokes the FIOQSIZE ioctl(2) and returns its errno or 0. */
 static int test_fioqsize_ioctl(int fd)
 {
@@ -3742,6 +3726,40 @@ static int test_fioqsize_ioctl(int fd)
 	return 0;
 }
 
+TEST(memfd_ftruncate_and_ioctl)
+{
+	struct landlock_ruleset_attr attr = {
+		.handled_access_fs = ACCESS_ALL,
+	};
+	int ruleset_fd, fd, i;
+
+	/*
+	 * We exercise the same test both with and without Landlock enabled, to
+	 * ensure that it behaves the same in both cases.
+	 */
+	for (i = 0; i < 2; i++) {
+		/* Creates a new memfd. */
+		fd = memfd_create("name", MFD_CLOEXEC);
+		ASSERT_LE(0, fd);
+
+		/*
+		 * Checks that operations associated with the opened file
+		 * (ftruncate, ioctl) are permitted on file descriptors that are
+		 * created in ways other than open(2).
+		 */
+		EXPECT_EQ(0, test_ftruncate(fd));
+		EXPECT_EQ(0, test_fioqsize_ioctl(fd));
+
+		ASSERT_EQ(0, close(fd));
+
+		/* Enables Landlock. */
+		ruleset_fd = landlock_create_ruleset(&attr, sizeof(attr), 0);
+		ASSERT_LE(0, ruleset_fd)
+		enforce_ruleset(_metadata, ruleset_fd);
+		ASSERT_EQ(0, close(ruleset_fd));
+	}
+}
+
 /*
  * Attempt ioctls on regular files, with file descriptors opened before and
  * after landlocking.
-- 
2.41.0.694.ge786442a9b-goog