[PATCH] selftests/landlock:Fix fs_test build issues with old libc

[Hu Yadi]

From: "Hu.Yadi" <hu.yadi@xxxxxxx>

Fixes: 04f9070e99a4 ("selftests/landlock: Add tests for pseudo filesystems")

one issues comes up while building selftest/landlock on my side
(gcc 7.3/glibc-2.28/kernel-4.19)

gcc -Wall -O2 -isystem   fs_test.c -lcap -o selftests/landlock/fs_test
fs_test.c:4575:9: error: initializer element is not constant
  .mnt = mnt_tmp,
         ^~~~~~~

Signed-off-by: Hu.Yadi <hu.yadi@xxxxxxx>
Suggested-by: Jiao <jiaoxupo@xxxxxxx>
Reviewed-by: Berlin <berlin@xxxxxxx>
---
 tools/testing/selftests/landlock/fs_test.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 18e1f86a6234..1f2584b4dfce 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -40,6 +40,7 @@ int renameat2(int olddirfd, const char *oldpath, int newdirfd,

 #define TMP_DIR "tmp"
 #define BINARY_PATH "./true"
+#define MNT_TMP_DATA "size=4m,mode=700"

 /* Paths (sibling number and depth) */
 static const char dir_s1d1[] = TMP_DIR "/s1d1";
@@ -4572,7 +4573,10 @@ FIXTURE_VARIANT(layout3_fs)
 /* clang-format off */
 FIXTURE_VARIANT_ADD(layout3_fs, tmpfs) {
 	/* clang-format on */
-	.mnt = mnt_tmp,
+	.mnt = {
+		.type = "tmpfs",
+		.data = MNT_TMP_DATA,
+	},
 	.file_path = file1_s1d1,
 };

--
2.23.0