[PATCH net-next v4 4/8] net: mctp: Add test for conflicting bind()s

[Matt Johnston <matt@codeconstruct.com.au>]

Test pairwise combinations of bind addresses and types.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>

---
v3:
- Moved test code to mctp/test/sock-test.c recently added in
  net-next, common bind test code in mctp/test/utils.c
v2:
- Remove unused bind test case
- Fix line lengths
---
 net/mctp/test/sock-test.c | 130 ++++++++++++++++++++++++++++++++++++++++++++++
 net/mctp/test/utils.c     |  22 ++++++++
 net/mctp/test/utils.h     |  10 ++++
 3 files changed, 162 insertions(+)

diff --git a/net/mctp/test/sock-test.c b/net/mctp/test/sock-test.c
index 4eb3a724dca39eb22615cbfc1201b45ee4c78d16..0cfc337be687e7ad903023d2fae9f12f75628532 100644
--- a/net/mctp/test/sock-test.c
+++ b/net/mctp/test/sock-test.c
@@ -215,9 +215,139 @@ static void mctp_test_sock_recvmsg_extaddr(struct kunit *test)
 	__mctp_sock_test_fini(test, dev, rt, sock);
 }
 
+static const struct mctp_test_bind_setup bind_addrany_netdefault_type1 = {
+	.bind_addr = MCTP_ADDR_ANY, .bind_net = MCTP_NET_ANY, .bind_type = 1,
+};
+
+static const struct mctp_test_bind_setup bind_addrany_net2_type1 = {
+	.bind_addr = MCTP_ADDR_ANY, .bind_net = 2, .bind_type = 1,
+};
+
+/* 1 is default net */
+static const struct mctp_test_bind_setup bind_addr8_net1_type1 = {
+	.bind_addr = 8, .bind_net = 1, .bind_type = 1,
+};
+
+static const struct mctp_test_bind_setup bind_addrany_net1_type1 = {
+	.bind_addr = MCTP_ADDR_ANY, .bind_net = 1, .bind_type = 1,
+};
+
+/* 2 is an arbitrary net */
+static const struct mctp_test_bind_setup bind_addr8_net2_type1 = {
+	.bind_addr = 8, .bind_net = 2, .bind_type = 1,
+};
+
+static const struct mctp_test_bind_setup bind_addr8_netdefault_type1 = {
+	.bind_addr = 8, .bind_net = MCTP_NET_ANY, .bind_type = 1,
+};
+
+static const struct mctp_test_bind_setup bind_addrany_net2_type2 = {
+	.bind_addr = MCTP_ADDR_ANY, .bind_net = 2, .bind_type = 2,
+};
+
+struct mctp_bind_pair_test {
+	const struct mctp_test_bind_setup *bind1;
+	const struct mctp_test_bind_setup *bind2;
+	int error;
+};
+
+/* Pairs of binds and whether they will conflict */
+static const struct mctp_bind_pair_test mctp_bind_pair_tests[] = {
+	/* Both ADDR_ANY, conflict */
+	{ &bind_addrany_netdefault_type1, &bind_addrany_netdefault_type1,
+	  EADDRINUSE },
+	/* Same specific EID, conflict */
+	{ &bind_addr8_netdefault_type1, &bind_addr8_netdefault_type1,
+	  EADDRINUSE },
+	/* ADDR_ANY vs specific EID, OK */
+	{ &bind_addrany_netdefault_type1, &bind_addr8_netdefault_type1, 0 },
+	/* ADDR_ANY different types, OK */
+	{ &bind_addrany_net2_type2, &bind_addrany_net2_type1, 0 },
+	/* ADDR_ANY different nets, OK */
+	{ &bind_addrany_net2_type1, &bind_addrany_netdefault_type1, 0 },
+
+	/* specific EID, NET_ANY (resolves to default)
+	 *  vs specific EID, explicit default net 1, conflict
+	 */
+	{ &bind_addr8_netdefault_type1, &bind_addr8_net1_type1, EADDRINUSE },
+
+	/* specific EID, net 1 vs specific EID, net 2, ok */
+	{ &bind_addr8_net1_type1, &bind_addr8_net2_type1, 0 },
+
+	/* ANY_ADDR, NET_ANY (doesn't resolve to default)
+	 *  vs ADDR_ANY, explicit default net 1, OK
+	 */
+	{ &bind_addrany_netdefault_type1, &bind_addrany_net1_type1, 0 },
+};
+
+static void mctp_bind_pair_desc(const struct mctp_bind_pair_test *t, char *desc)
+{
+	snprintf(desc, KUNIT_PARAM_DESC_SIZE,
+		 "{bind(addr %d, type %d, net %d)} {bind(addr %d, type %d, net %d)} -> error %d",
+		 t->bind1->bind_addr, t->bind1->bind_type, t->bind1->bind_net,
+		 t->bind2->bind_addr, t->bind2->bind_type, t->bind2->bind_net,
+		 t->error);
+}
+
+KUNIT_ARRAY_PARAM(mctp_bind_pair, mctp_bind_pair_tests, mctp_bind_pair_desc);
+
+static int
+mctp_test_bind_conflicts_inner(struct kunit *test,
+			       const struct mctp_test_bind_setup *bind1,
+			       const struct mctp_test_bind_setup *bind2)
+{
+	struct socket *sock1 = NULL, *sock2 = NULL, *sock3 = NULL;
+	int bind_errno;
+
+	/* Bind to first address, always succeeds */
+	mctp_test_bind_run(test, bind1, &bind_errno, &sock1);
+	KUNIT_EXPECT_EQ(test, bind_errno, 0);
+
+	/* A second identical bind always fails */
+	mctp_test_bind_run(test, bind1, &bind_errno, &sock2);
+	KUNIT_EXPECT_EQ(test, -bind_errno, EADDRINUSE);
+
+	/* A different bind, result is returned */
+	mctp_test_bind_run(test, bind2, &bind_errno, &sock3);
+
+	if (sock1)
+		sock_release(sock1);
+	if (sock2)
+		sock_release(sock2);
+	if (sock3)
+		sock_release(sock3);
+
+	return bind_errno;
+}
+
+static void mctp_test_bind_conflicts(struct kunit *test)
+{
+	const struct mctp_bind_pair_test *pair;
+	int bind_errno;
+
+	pair = test->param_value;
+
+	bind_errno =
+		mctp_test_bind_conflicts_inner(test, pair->bind1, pair->bind2);
+	KUNIT_EXPECT_EQ(test, -bind_errno, pair->error);
+
+	/* swapping the calls, the second bind should still fail */
+	bind_errno =
+		mctp_test_bind_conflicts_inner(test, pair->bind2, pair->bind1);
+	KUNIT_EXPECT_EQ(test, -bind_errno, pair->error);
+}
+
+static void mctp_test_assumptions(struct kunit *test)
+{
+	/* check assumption of default net from bind_addr8_net1_type1 */
+	KUNIT_ASSERT_EQ(test, mctp_default_net(&init_net), 1);
+}
+
 static struct kunit_case mctp_test_cases[] = {
+	KUNIT_CASE(mctp_test_assumptions),
 	KUNIT_CASE(mctp_test_sock_sendmsg_extaddr),
 	KUNIT_CASE(mctp_test_sock_recvmsg_extaddr),
+	KUNIT_CASE_PARAM(mctp_test_bind_conflicts, mctp_bind_pair_gen_params),
 	{}
 };
 
diff --git a/net/mctp/test/utils.c b/net/mctp/test/utils.c
index 01f5af416b814baf812b4352c513ffcdd9939cb2..c971e2c326f3564f95b3f693c450b3e6f3d9c594 100644
--- a/net/mctp/test/utils.c
+++ b/net/mctp/test/utils.c
@@ -258,3 +258,25 @@ struct sk_buff *__mctp_test_create_skb_data(const struct mctp_hdr *hdr,
 
 	return skb;
 }
+
+void mctp_test_bind_run(struct kunit *test,
+			const struct mctp_test_bind_setup *setup,
+			int *ret_bind_errno, struct socket **sock)
+{
+	struct sockaddr_mctp addr;
+	int rc;
+
+	*ret_bind_errno = -EIO;
+
+	rc = sock_create_kern(&init_net, AF_MCTP, SOCK_DGRAM, 0, sock);
+	KUNIT_ASSERT_EQ(test, rc, 0);
+
+	memset(&addr, 0x0, sizeof(addr));
+	addr.smctp_family = AF_MCTP;
+	addr.smctp_network = setup->bind_net;
+	addr.smctp_addr.s_addr = setup->bind_addr;
+	addr.smctp_type = setup->bind_type;
+
+	*ret_bind_errno =
+		kernel_bind(*sock, (struct sockaddr *)&addr, sizeof(addr));
+}
diff --git a/net/mctp/test/utils.h b/net/mctp/test/utils.h
index f10d1d9066ccde53bbaf471ea79b87b1d94cd755..7dd1a92ab770995db506c24dc805bb9e0839eeef 100644
--- a/net/mctp/test/utils.h
+++ b/net/mctp/test/utils.h
@@ -31,6 +31,12 @@ struct mctp_test_pktqueue {
 	struct sk_buff_head pkts;
 };
 
+struct mctp_test_bind_setup {
+	mctp_eid_t bind_addr;
+	int bind_net;
+	u8 bind_type;
+};
+
 struct mctp_test_dev *mctp_test_create_dev(void);
 struct mctp_test_dev *mctp_test_create_dev_lladdr(unsigned short lladdr_len,
 						  const unsigned char *lladdr);
@@ -61,4 +67,8 @@ struct sk_buff *__mctp_test_create_skb_data(const struct mctp_hdr *hdr,
 #define mctp_test_create_skb_data(h, d) \
 	__mctp_test_create_skb_data(h, d, sizeof(*d))
 
+void mctp_test_bind_run(struct kunit *test,
+			const struct mctp_test_bind_setup *setup,
+			int *ret_bind_errno, struct socket **sock);
+
 #endif /* __NET_MCTP_TEST_UTILS_H */

-- 
2.43.0