[PATCH v2 4/6] selftests/landlock: Test ioctl with memfds

[Günther Noack]

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 at google.com>
---
 tools/testing/selftests/landlock/fs_test.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 0f0899768fe7..ebd93e895775 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -3716,18 +3716,20 @@ TEST_F_FORK(ftruncate, open_and_ftruncate_in_different_processes)
 	ASSERT_EQ(0, close(socket_fds[1]));
 }
 
-TEST(memfd_ftruncate)
+TEST(memfd_ftruncate_and_ioctl)
 {
-	int fd;
+	int fd, n;
 
 	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).
+	 * 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, ioctl(fd, FIONREAD, &n));
 
 	ASSERT_EQ(0, close(fd));
 }
-- 
2.41.0.162.gfafddb0af9-goog