[PATCH 3/3] firewire: core: add KUnit tests for failure of tree building

[Takashi Sakamoto]

Abdun Nihaal has reported a memory leak when tree building fails in the
middle of self ID sequence enumeration. This is caused by an invalid
self ID sequence and is not a common occurrence.

This commit is intended to assist in fixing the issue by adding KUnit
tests to show the cases in which the memory leak is triggered. The leak
occurs internally in the build_tree() function, therefore it cannot be
detected directly by the tests.

Signed-off-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx>
---
 drivers/firewire/node-tree-test.c | 84 +++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/drivers/firewire/node-tree-test.c b/drivers/firewire/node-tree-test.c
index 6f404df3d50e..251c0113639f 100644
--- a/drivers/firewire/node-tree-test.c
+++ b/drivers/firewire/node-tree-test.c
@@ -506,6 +506,86 @@ static void node_tree_test_four_nodes_case3(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, data->release_count, 4);
 }
 
+static void node_tree_test_invalid_extended_self_id_sequence(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// content of self ID packet for the phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000d1, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	// TODO: Memory leak.
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static void node_tree_test_invalid_phy_id(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// phy ID for phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x8f0000d0, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	// TODO: Memory leak.
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static void node_tree_test_invalid_child_port_count(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// count of child ports for phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000fc, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	// TODO: Memory leak.
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static void node_tree_test_invalid_parent_port_count(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// count of parent ports for phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000e8, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	// TODO: Memory leak.
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
 static struct kunit_case node_tree_test_cases[] = {
 	KUNIT_CASE(node_tree_test_two_nodes),
 	KUNIT_CASE(node_tree_test_two_nodes_1394a),
@@ -515,6 +595,10 @@ static struct kunit_case node_tree_test_cases[] = {
 	KUNIT_CASE(node_tree_test_four_nodes_case1),
 	KUNIT_CASE(node_tree_test_four_nodes_case2),
 	KUNIT_CASE(node_tree_test_four_nodes_case3),
+	KUNIT_CASE(node_tree_test_invalid_extended_self_id_sequence),
+	KUNIT_CASE(node_tree_test_invalid_phy_id),
+	KUNIT_CASE(node_tree_test_invalid_child_port_count),
+	KUNIT_CASE(node_tree_test_invalid_parent_port_count),
 	{}
 };
 
-- 
2.53.0