[LTP] [PATCH v1] chmod02.c: Block mode changes of symlinks

[Wei Gao]

Signed-off-by: Wei Gao <wegao@suse.com>
---
 runtest/syscalls                           |  1 +
 testcases/kernel/syscalls/chmod/.gitignore |  1 +
 testcases/kernel/syscalls/chmod/chmod02.c  | 68 ++++++++++++++++++++++
 3 files changed, 70 insertions(+)
 create mode 100644 testcases/kernel/syscalls/chmod/chmod02.c

diff --git a/runtest/syscalls b/runtest/syscalls
index fe9ad0895..b8f1d53d5 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -66,6 +66,7 @@ chdir04 chdir04
 
 chmod01 chmod01
 chmod01A symlink01 -T chmod01
+chmod02 chmod02
 chmod03 chmod03
 chmod05 chmod05
 chmod06 chmod06
diff --git a/testcases/kernel/syscalls/chmod/.gitignore b/testcases/kernel/syscalls/chmod/.gitignore
index 27ddfce16..9cc923e69 100644
--- a/testcases/kernel/syscalls/chmod/.gitignore
+++ b/testcases/kernel/syscalls/chmod/.gitignore
@@ -1,4 +1,5 @@
 /chmod01
+/chmod02
 /chmod03
 /chmod05
 /chmod06
diff --git a/testcases/kernel/syscalls/chmod/chmod02.c b/testcases/kernel/syscalls/chmod/chmod02.c
new file mode 100644
index 000000000..412c78e9a
--- /dev/null
+++ b/testcases/kernel/syscalls/chmod/chmod02.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2024 Wei Gao <wegao@suse.com>
+ */
+
+/*\
+ * [Description]
+ *
+ * Test for kernel commit 5d1f903f75a80daa4dfb3d84e114ec8ecbf29956
+ * "attr: block mode changes of symlinks".
+ *
+ */
+
+#include "lapi/fcntl.h"
+#include "tst_test.h"
+
+#define MODE 0644
+#define TESTFILE "testfile"
+#define TESTFILE_SYMLINK "testfile_symlink"
+
+static void run(void)
+{
+	struct stat stat_file, stat_sym;
+	int mode = 0;
+	char fd_path[100];
+
+	int fd = SAFE_OPEN(TESTFILE_SYMLINK, O_PATH | O_NOFOLLOW);
+
+	sprintf(fd_path, "/proc/self/fd/%d", fd);
+
+	TST_EXP_FAIL(chmod(fd_path, mode), ENOTSUP, "chmod(%s, %04o)",
+			TESTFILE_SYMLINK, mode);
+
+	SAFE_STAT(TESTFILE, &stat_file);
+	SAFE_LSTAT(TESTFILE_SYMLINK, &stat_sym);
+
+	stat_file.st_mode &= ~S_IFREG;
+	stat_sym.st_mode &= ~S_IFLNK;
+
+	if (stat_file.st_mode == (unsigned int)mode) {
+		tst_res(TFAIL, "stat(%s) mode=%04o",
+				TESTFILE, stat_file.st_mode);
+	} else {
+		tst_res(TPASS, "stat(%s) mode=%04o",
+				TESTFILE, stat_file.st_mode);
+	}
+
+	if (stat_sym.st_mode == (unsigned int)mode) {
+		tst_res(TFAIL, "stat(%s) mode=%04o",
+				TESTFILE_SYMLINK, stat_sym.st_mode);
+	} else {
+		tst_res(TPASS, "stat(%s) mode=%04o",
+				TESTFILE_SYMLINK, stat_sym.st_mode);
+	}
+}
+
+static void setup(void)
+{
+	SAFE_TOUCH(TESTFILE, MODE, NULL);
+	SAFE_SYMLINK(TESTFILE, TESTFILE_SYMLINK);
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.test_all = run,
+	.needs_tmpdir = 1,
+	.min_kver = "6.6",
+};
-- 
2.35.3