[PATCH v6 4/4] selftests/liveupdate: add test cases for LIVEUPDATE_SESSION_GET_NAME

[luca.boccassi@gmail.com]

From: Luca Boccassi <luca.boccassi@gmail.com>

Verify that the new LIVEUPDATE_SESSION_GET_NAME ioctl works
as expected via new test cases in the existing liveupdate selftest.

Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>
---
v5: merge with LUO_SESSION_MAGIC series as they both change the same
    unit test file, to avoid merge conflicts
    split into separate patch
v6: add more test cases as suggested
    more verbose commit message

 .../testing/selftests/liveupdate/liveupdate.c | 138 ++++++++++++++++++
 1 file changed, 138 insertions(+)

diff --git a/tools/testing/selftests/liveupdate/liveupdate.c b/tools/testing/selftests/liveupdate/liveupdate.c
index d132b4685f76..ffbcbd465c9b 100644
--- a/tools/testing/selftests/liveupdate/liveupdate.c
+++ b/tools/testing/selftests/liveupdate/liveupdate.c
@@ -105,6 +105,22 @@ static int create_session(int lu_fd, const char *name)
 	return args.fd;
 }
 
+/* Helper function to get a session name via ioctl. */
+static int get_session_name(int session_fd, char *name, size_t name_len)
+{
+	struct liveupdate_session_get_name args = {};
+
+	args.size = sizeof(args);
+
+	if (ioctl(session_fd, LIVEUPDATE_SESSION_GET_NAME, &args))
+		return -errno;
+
+	strncpy(name, (char *)args.name, name_len - 1);
+	name[name_len - 1] = '\0';
+
+	return 0;
+}
+
 /*
  * Test Case: Create Duplicate Session
  *
@@ -385,4 +401,126 @@ TEST_F(liveupdate_device, session_fstat)
 	ASSERT_EQ(close(session_fd2), 0);
 }
 
+/*
+ * Test Case: Get Session Name
+ *
+ * Verifies that the full session name can be retrieved from a session file
+ * descriptor via ioctl.
+ */
+TEST_F(liveupdate_device, get_session_name)
+{
+	char name_buf[LIVEUPDATE_SESSION_NAME_LENGTH] = {};
+	const char *session_name = "get-name-test-session";
+	int session_fd;
+
+	self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
+	if (self->fd1 < 0 && errno == ENOENT)
+		SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
+	ASSERT_GE(self->fd1, 0);
+
+	session_fd = create_session(self->fd1, session_name);
+	ASSERT_GE(session_fd, 0);
+
+	ASSERT_EQ(get_session_name(session_fd, name_buf, sizeof(name_buf)), 0);
+	ASSERT_STREQ(name_buf, session_name);
+
+	ASSERT_EQ(close(session_fd), 0);
+}
+
+/*
+ * Test Case: Get Session Name at Maximum Length
+ *
+ * Verifies that a session name using the full LIVEUPDATE_SESSION_NAME_LENGTH
+ * (minus the null terminator) can be correctly retrieved.
+ */
+TEST_F(liveupdate_device, get_session_name_max_length)
+{
+	char name_buf[LIVEUPDATE_SESSION_NAME_LENGTH] = {};
+	char long_name[LIVEUPDATE_SESSION_NAME_LENGTH];
+	int session_fd;
+
+	memset(long_name, 'A', sizeof(long_name) - 1);
+	long_name[sizeof(long_name) - 1] = '\0';
+
+	self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
+	if (self->fd1 < 0 && errno == ENOENT)
+		SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
+	ASSERT_GE(self->fd1, 0);
+
+	session_fd = create_session(self->fd1, long_name);
+	ASSERT_GE(session_fd, 0);
+
+	ASSERT_EQ(get_session_name(session_fd, name_buf, sizeof(name_buf)), 0);
+	ASSERT_STREQ(name_buf, long_name);
+
+	ASSERT_EQ(close(session_fd), 0);
+}
+
+/*
+ * Test Case: Create Session with No Null Termination
+ *
+ * Verifies that filling the entire 64-byte name field with non-null characters
+ * (no '\0' terminator) is handled safely by the kernel. The kernel's strscpy
+ * truncates to 63 characters, which we verify via get_session_name.
+ */
+TEST_F(liveupdate_device, create_session_no_null_termination)
+{
+	struct liveupdate_ioctl_create_session args = {};
+	char expected_name[LIVEUPDATE_SESSION_NAME_LENGTH];
+	char name_buf[LIVEUPDATE_SESSION_NAME_LENGTH] = {};
+	int session_fd;
+
+	self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
+	if (self->fd1 < 0 && errno == ENOENT)
+		SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
+	ASSERT_GE(self->fd1, 0);
+
+	/* Fill entire name field with 'X', no null terminator */
+	args.size = sizeof(args);
+	memset(args.name, 'X', sizeof(args.name));
+
+	ASSERT_EQ(ioctl(self->fd1, LIVEUPDATE_IOCTL_CREATE_SESSION, &args), 0);
+	session_fd = args.fd;
+	ASSERT_GE(session_fd, 0);
+
+	/* Kernel should have truncated to 63 chars + '\0' */
+	memset(expected_name, 'X', sizeof(expected_name) - 1);
+	expected_name[sizeof(expected_name) - 1] = '\0';
+
+	ASSERT_EQ(get_session_name(session_fd, name_buf, sizeof(name_buf)), 0);
+	ASSERT_STREQ(name_buf, expected_name);
+
+	ASSERT_EQ(close(session_fd), 0);
+}
+
+/*
+ * Test Case: Create Session with Empty Name
+ *
+ * Verifies that creating a session with an empty string name succeeds,
+ * and that creating a second session with the same empty name fails
+ * with EEXIST.
+ */
+TEST_F(liveupdate_device, create_session_empty_name)
+{
+	char name_buf[LIVEUPDATE_SESSION_NAME_LENGTH] = {};
+	int session_fd1, session_fd2;
+
+	self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
+	if (self->fd1 < 0 && errno == ENOENT)
+		SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
+	ASSERT_GE(self->fd1, 0);
+
+	session_fd1 = create_session(self->fd1, "");
+	ASSERT_GE(session_fd1, 0);
+
+	ASSERT_EQ(get_session_name(session_fd1, name_buf, sizeof(name_buf)), 0);
+	ASSERT_STREQ(name_buf, "");
+
+	/* A second empty-name session must fail as duplicate */
+	session_fd2 = create_session(self->fd1, "");
+	EXPECT_EQ(session_fd2, -EEXIST);
+
+	ASSERT_EQ(close(session_fd1), 0);
+}
+
 TEST_HARNESS_MAIN
-- 
2.47.3