[LTP] [PATCH] syscalls/fsmount: add coverage for fsmount01.c

[YouZhi Zhao]

Can I create a file and write a file verification after adding the setting for MOUNT_STTR_RDONLY

Signed-off-by: Youzhi Zhao <zhaoyouzhi@uniontech.com>
---
 testcases/kernel/syscalls/fsmount/fsmount01.c | 31 ++++++++++++++++---
 1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/testcases/kernel/syscalls/fsmount/fsmount01.c b/testcases/kernel/syscalls/fsmount/fsmount01.c
index 5f755863f..8bf4a5a0a 100644
--- a/testcases/kernel/syscalls/fsmount/fsmount01.c
+++ b/testcases/kernel/syscalls/fsmount/fsmount01.c
@@ -10,6 +10,7 @@
 #include "lapi/fsmount.h"

 #define MNTPOINT	"mntpoint"
+#define TEST_FILE       MNTPOINT "/testfile"

 #define TCASE_ENTRY(_flags, _attrs)	{.name = "Flag " #_flags ", Attr " #_attrs, .flags = _flags, .attrs = _attrs}

@@ -36,6 +37,24 @@ static struct tcase {
 	TCASE_ENTRY(FSMOUNT_CLOEXEC, MOUNT_ATTR_NODIRATIME),
 };

+static void verify_mount_readonly(void)
+{
+        int fd;
+
+        fd = open(TEST_FILE, O_WRONLY | O_CREAT, 0644);
+        if (fd == -1) {
+                if (errno == EROFS) {
+                        tst_res(TPASS, "MOUNT_ATTR_RDONLY verified: Cannot create file, filesystem is read-only.");
+                } else {
+                        tst_res(TFAIL | TTERRNO, "Failed to create file for unknown reason.");
+                }
+        } else {
+                tst_res(TFAIL, "MOUNT_ATTR_RDONLY verification failed: File created on supposed read-only filesystem.");
+                close(fd);
+                unlink(TEST_FILE);
+        }
+}
+
 static void run(unsigned int n)
 {
 	struct tcase *tc = &tcases[n];
@@ -81,10 +100,14 @@ static void run(unsigned int n)
 		return;
 	}

-	if (tst_is_mounted_at_tmpdir(MNTPOINT)) {
-		SAFE_UMOUNT(MNTPOINT);
-		tst_res(TPASS, "%s: fsmount() passed", tc->name);
-	}
+        if (tst_is_mounted_at_tmpdir(MNTPOINT)) {
+                if (tc->attrs & MOUNT_ATTR_RDONLY) {
+                        verify_mount_readonly();
+                } else {
+                        tst_res(TPASS, "%s: fsmount() passed", tc->name);
+                }
+                SAFE_UMOUNT(MNTPOINT);
+        }
 }

 static struct tst_test test = {
--
2.43.0