selftest: tcp: Add bind() tests for IPV6_V6ONLY.

bhash2 was not well tested for IPv6-only sockets.

This patch adds test cases where we set IPV6_V6ONLY for per-fixture
bind() calls if variant->ipv6_only[i] is true.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240326204251.51301-8-kuniyu@amazon.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/net/bind_wildcard.c

@@ -42,6 +42,7 @@ FIXTURE_VARIANT(bind_wildcard)
 {
 	sa_family_t family[2];
 	const void *addr[2];
+	bool ipv6_only[2];
 
 	/* 6 bind() calls below follow two bind() for the defined 2 addresses:
 	 *
@@ -87,6 +88,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_any_only)
+{
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_any, &in6addr_any},
+	.ipv6_only = {false, true},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_local)
 {
 	.family = {AF_INET, AF_INET6},
@@ -127,6 +139,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_any_only)
+{
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_loopback, &in6addr_any},
+	.ipv6_only = {false, true},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_local)
 {
 	.family = {AF_INET, AF_INET6},
@@ -168,6 +191,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v4_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v4_any)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_any, &in4addr_any},
+	.ipv6_only = {true, false},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v4_local)
 {
 	.family = {AF_INET6, AF_INET},
@@ -178,6 +212,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v4_local)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v4_local)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_any, &in4addr_loopback},
+	.ipv6_only = {true, false},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v4_any)
 {
 	.family = {AF_INET6, AF_INET},
@@ -249,6 +294,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_local)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v6_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_loopback},
+	.ipv6_only = {true, false},
+	.expected_errno = {0, EADDRINUSE,
+			   0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_v4mapped_any)
 {
 	.family = {AF_INET6, AF_INET6},
@@ -259,6 +315,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_v4mapped_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v6_v4mapped_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_v4mapped_any},
+	.ipv6_only = {true, false},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_v4mapped_local)
 {
 	.family = {AF_INET6, AF_INET6},
@@ -269,6 +336,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_v4mapped_local)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v6_v4mapped_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_v4mapped_loopback},
+	.ipv6_only = {true, false},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_any)
 {
 	.family = {AF_INET6, AF_INET6},
@@ -279,6 +357,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_any_only)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_loopback, &in6addr_any},
+	.ipv6_only = {false, true},
+	.expected_errno = {0, EADDRINUSE,
+			   0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_v4mapped_any)
 {
 	.family = {AF_INET6, AF_INET6},
@@ -309,6 +398,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v6_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v6_any_only)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_any, &in6addr_any},
+	.ipv6_only = {false, true},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v6_local)
 {
 	.family = {AF_INET6, AF_INET6},
@@ -339,6 +439,17 @@ FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_loopback_v6_any)
 			   EADDRINUSE, EADDRINUSE},
 };
 
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_loopback_v6_any_only)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_loopback, &in6addr_any},
+	.ipv6_only = {false, true},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+};
+
 FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_loopback_v6_local)
 {
 	.family = {AF_INET6, AF_INET6},
@@ -415,6 +526,11 @@ void bind_socket(struct __test_metadata *_metadata,
 	self->fd[i] = socket(self->addr[i].addr.sa_family, SOCK_STREAM, 0);
 	ASSERT_GT(self->fd[i], 0);
 
+	if (i < 2 && variant->ipv6_only[i]) {
+		ret = setsockopt(self->fd[i], SOL_IPV6, IPV6_V6ONLY, &(int){1}, sizeof(int));
+		ASSERT_EQ(ret, 0);
+	}
+
 	self->addr[i].addr4.sin_port = self->addr[0].addr4.sin_port;
 
 	ret = bind(self->fd[i], &self->addr[i].addr, self->addrlen[i]);