Merge branch 'tcp-fix-bind-regression-and-more-tests'

Kuniyuki Iwashima says:

====================
tcp: Fix bind() regression and more tests.

bhash2 has not been well tested for IPV6_V6ONLY option.

This series fixes two regression around IPV6_V6ONLY, one of which
has been there since bhash2 introduction, and another is introduced
by a recent change.

Also, this series adds as many tests as possible to catch regression
easily.  The baseline is 28044fc1d495~ which is pre-bhash2 commit.

 Tested on 28044fc1d495~:
  # PASSED: 132 / 132 tests passed.
  # Totals: pass:132 fail:0 xfail:0 xpass:0 skip:0 error:0

 net.git:
  # FAILED: 125 / 132 tests passed.
  # Totals: pass:125 fail:7 xfail:0 xpass:0 skip:0 error:0

 With this series:
  # PASSED: 132 / 132 tests passed.
  # Totals: pass:132 fail:0 xfail:0 xpass:0 skip:0 error:0

v1: https://lore.kernel.org/netdev/20240325181923.48769-1-kuniyu@amazon.com/
====================

Link: https://lore.kernel.org/r/20240326204251.51301-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 736 insertions, 77 deletions

diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index c038e28e2f1e66..3b38610958ee4b 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -203,8 +203,15 @@ static bool __inet_bhash2_conflict(const struct sock *sk, struct sock *sk2,
 				   kuid_t sk_uid, bool relax,
 				   bool reuseport_cb_ok, bool reuseport_ok)
 {
-	if (sk->sk_family == AF_INET && ipv6_only_sock(sk2))
-		return false;
+	if (ipv6_only_sock(sk2)) {
+		if (sk->sk_family == AF_INET)
+			return false;
+
+#if IS_ENABLED(CONFIG_IPV6)
+		if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
+			return false;
+#endif
+	}
 
 	return inet_bind_conflict(sk, sk2, sk_uid, relax,
 				  reuseport_cb_ok, reuseport_ok);
@@ -287,6 +294,7 @@ static bool inet_bhash2_addr_any_conflict(const struct sock *sk, int port, int l
 	struct sock_reuseport *reuseport_cb;
 	struct inet_bind_hashbucket *head2;
 	struct inet_bind2_bucket *tb2;
+	bool conflict = false;
 	bool reuseport_cb_ok;
 
 	rcu_read_lock();
@@ -299,18 +307,20 @@ static bool inet_bhash2_addr_any_conflict(const struct sock *sk, int port, int l
 
 	spin_lock(&head2->lock);
 
-	inet_bind_bucket_for_each(tb2, &head2->chain)
-		if (inet_bind2_bucket_match_addr_any(tb2, net, port, l3mdev, sk))
-			break;
+	inet_bind_bucket_for_each(tb2, &head2->chain) {
+		if (!inet_bind2_bucket_match_addr_any(tb2, net, port, l3mdev, sk))
+			continue;
 
-	if (tb2 && inet_bhash2_conflict(sk, tb2, uid, relax, reuseport_cb_ok,
-					reuseport_ok)) {
-		spin_unlock(&head2->lock);
-		return true;
+		if (!inet_bhash2_conflict(sk, tb2, uid, relax, reuseport_cb_ok,	reuseport_ok))
+			continue;
+
+		conflict = true;
+		break;
 	}
 
 	spin_unlock(&head2->lock);
-	return false;
+
+	return conflict;
 }
 
 /*
diff --git a/tools/testing/selftests/net/bind_wildcard.c b/tools/testing/selftests/net/bind_wildcard.c
index a2662348cdb1a2..b7b54d646b937c 100644
--- a/tools/testing/selftests/net/bind_wildcard.c
+++ b/tools/testing/selftests/net/bind_wildcard.c
@@ -6,7 +6,9 @@
 
 #include "../kselftest_harness.h"
 
-struct in6_addr in6addr_v4mapped_any = {
+static const __u32 in4addr_any = INADDR_ANY;
+static const __u32 in4addr_loopback = INADDR_LOOPBACK;
+static const struct in6_addr in6addr_v4mapped_any = {
 	.s6_addr = {
 		0, 0, 0, 0,
 		0, 0, 0, 0,
@@ -14,8 +16,7 @@ struct in6_addr in6addr_v4mapped_any = {
 		0, 0, 0, 0
 	}
 };
-
-struct in6_addr in6addr_v4mapped_loopback = {
+static const struct in6_addr in6addr_v4mapped_loopback = {
 	.s6_addr = {
 		0, 0, 0, 0,
 		0, 0, 0, 0,
@@ -24,137 +25,785 @@ struct in6_addr in6addr_v4mapped_loopback = {
 	}
 };
 
+#define NR_SOCKETS 8
+
 FIXTURE(bind_wildcard)
 {
-	struct sockaddr_in addr4;
-	struct sockaddr_in6 addr6;
+	int fd[NR_SOCKETS];
+	socklen_t addrlen[NR_SOCKETS];
+	union {
+		struct sockaddr addr;
+		struct sockaddr_in addr4;
+		struct sockaddr_in6 addr6;
+	} addr[NR_SOCKETS];
 };
 
 FIXTURE_VARIANT(bind_wildcard)
 {
-	const __u32 addr4_const;
-	const struct in6_addr *addr6_const;
-	int expected_errno;
+	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:
+	 *
+	 *   0.0.0.0
+	 *   127.0.0.1
+	 *   ::
+	 *   ::1
+	 *   ::ffff:0.0.0.0
+	 *   ::ffff:127.0.0.1
+	 */
+	int expected_errno[NR_SOCKETS];
+	int expected_reuse_errno[NR_SOCKETS];
+};
+
+/* (IPv4, IPv4) */
+FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v4_local)
+{
+	.family = {AF_INET, AF_INET},
+	.addr = {&in4addr_any, &in4addr_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v4_any)
+{
+	.family = {AF_INET, AF_INET},
+	.addr = {&in4addr_loopback, &in4addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
 };
 
+/* (IPv4, IPv6) */
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_any)
 {
-	.addr4_const = INADDR_ANY,
-	.addr6_const = &in6addr_any,
-	.expected_errno = EADDRINUSE,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_any, &in6addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_local)
 {
-	.addr4_const = INADDR_ANY,
-	.addr6_const = &in6addr_loopback,
-	.expected_errno = 0,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_any, &in6addr_loopback},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_v4mapped_any)
 {
-	.addr4_const = INADDR_ANY,
-	.addr6_const = &in6addr_v4mapped_any,
-	.expected_errno = EADDRINUSE,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_any, &in6addr_v4mapped_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_v4mapped_local)
 {
-	.addr4_const = INADDR_ANY,
-	.addr6_const = &in6addr_v4mapped_loopback,
-	.expected_errno = EADDRINUSE,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_any, &in6addr_v4mapped_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_any)
 {
-	.addr4_const = INADDR_LOOPBACK,
-	.addr6_const = &in6addr_any,
-	.expected_errno = EADDRINUSE,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_loopback, &in6addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_local)
 {
-	.addr4_const = INADDR_LOOPBACK,
-	.addr6_const = &in6addr_loopback,
-	.expected_errno = 0,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_loopback, &in6addr_loopback},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_v4mapped_any)
 {
-	.addr4_const = INADDR_LOOPBACK,
-	.addr6_const = &in6addr_v4mapped_any,
-	.expected_errno = EADDRINUSE,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_loopback, &in6addr_v4mapped_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
 };
 
 FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_v4mapped_local)
 {
-	.addr4_const = INADDR_LOOPBACK,
-	.addr6_const = &in6addr_v4mapped_loopback,
-	.expected_errno = EADDRINUSE,
+	.family = {AF_INET, AF_INET6},
+	.addr = {&in4addr_loopback, &in6addr_v4mapped_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+/* (IPv6, IPv4) */
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v4_any)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_any, &in4addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v4_local)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_any, &in4addr_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v4_any)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_loopback, &in4addr_any},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v4_local)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_loopback, &in4addr_loopback},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v4_any)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_v4mapped_any, &in4addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v4_local)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_v4mapped_any, &in4addr_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_local_v4_any)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_v4mapped_loopback, &in4addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_local_v4_local)
+{
+	.family = {AF_INET6, AF_INET},
+	.addr = {&in6addr_v4mapped_loopback, &in4addr_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+/* (IPv6, IPv6) */
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v6_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_any},
+	.ipv6_only = {true, false},
+	.expected_errno = {0, EADDRINUSE,
+			   0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_any_only)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_any},
+	.ipv6_only = {false, true},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_only_v6_any_only)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_any},
+	.ipv6_only = {true, true},
+	.expected_errno = {0, EADDRINUSE,
+			   0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 0, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 0, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_v4mapped_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_v4mapped_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_any_v6_v4mapped_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_any, &in6addr_v4mapped_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_loopback, &in6addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 0, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_v4mapped_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_loopback, &in6addr_v4mapped_any},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_local_v6_v4mapped_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_loopback, &in6addr_v4mapped_loopback},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v6_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_any, &in6addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v6_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_any, &in6addr_loopback},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_any_v6_v4mapped_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_any, &in6addr_v4mapped_loopback},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_loopback_v6_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_loopback, &in6addr_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 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},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_loopback_v6_local)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_loopback, &in6addr_loopback},
+	.expected_errno = {0, 0,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+FIXTURE_VARIANT_ADD(bind_wildcard, v6_v4mapped_loopback_v6_v4mapped_any)
+{
+	.family = {AF_INET6, AF_INET6},
+	.addr = {&in6addr_v4mapped_loopback, &in6addr_v4mapped_any},
+	.expected_errno = {0, EADDRINUSE,
+			   EADDRINUSE, EADDRINUSE,
+			   EADDRINUSE, 0,
+			   EADDRINUSE, EADDRINUSE},
+	.expected_reuse_errno = {0, 0,
+				 EADDRINUSE, EADDRINUSE,
+				 EADDRINUSE, 0,
+				 EADDRINUSE, EADDRINUSE},
+};
+
+static void setup_addr(FIXTURE_DATA(bind_wildcard) *self, int i,
+		       int family, const void *addr_const)
+{
+	if (family == AF_INET) {
+		struct sockaddr_in *addr4 = &self->addr[i].addr4;
+		const __u32 *addr4_const = addr_const;
+
+		addr4->sin_family = AF_INET;
+		addr4->sin_port = htons(0);
+		addr4->sin_addr.s_addr = htonl(*addr4_const);
+
+		self->addrlen[i] = sizeof(struct sockaddr_in);
+	} else {
+		struct sockaddr_in6 *addr6 = &self->addr[i].addr6;
+		const struct in6_addr *addr6_const = addr_const;
+
+		addr6->sin6_family = AF_INET6;
+		addr6->sin6_port = htons(0);
+		addr6->sin6_addr = *addr6_const;
+
+		self->addrlen[i] = sizeof(struct sockaddr_in6);
+	}
+}
+
 FIXTURE_SETUP(bind_wildcard)
 {
-	self->addr4.sin_family = AF_INET;
-	self->addr4.sin_port = htons(0);
-	self->addr4.sin_addr.s_addr = htonl(variant->addr4_const);
+	setup_addr(self, 0, variant->family[0], variant->addr[0]);
+	setup_addr(self, 1, variant->family[1], variant->addr[1]);
+
+	setup_addr(self, 2, AF_INET, &in4addr_any);
+	setup_addr(self, 3, AF_INET, &in4addr_loopback);
 
-	self->addr6.sin6_family = AF_INET6;
-	self->addr6.sin6_port = htons(0);
-	self->addr6.sin6_addr = *variant->addr6_const;
+	setup_addr(self, 4, AF_INET6, &in6addr_any);
+	setup_addr(self, 5, AF_INET6, &in6addr_loopback);
+	setup_addr(self, 6, AF_INET6, &in6addr_v4mapped_any);
+	setup_addr(self, 7, AF_INET6, &in6addr_v4mapped_loopback);
 }
 
 FIXTURE_TEARDOWN(bind_wildcard)
 {
+	int i;
+
+	for (i = 0; i < NR_SOCKETS; i++)
+		close(self->fd[i]);
 }
 
-void bind_sockets(struct __test_metadata *_metadata,
-		  FIXTURE_DATA(bind_wildcard) *self,
-		  int expected_errno,
-		  struct sockaddr *addr1, socklen_t addrlen1,
-		  struct sockaddr *addr2, socklen_t addrlen2)
+void bind_socket(struct __test_metadata *_metadata,
+		 FIXTURE_DATA(bind_wildcard) *self,
+		 const FIXTURE_VARIANT(bind_wildcard) *variant,
+		 int i, int reuse)
 {
-	int fd[2];
 	int ret;
 
-	fd[0] = socket(addr1->sa_family, SOCK_STREAM, 0);
-	ASSERT_GT(fd[0], 0);
+	self->fd[i] = socket(self->addr[i].addr.sa_family, SOCK_STREAM, 0);
+	ASSERT_GT(self->fd[i], 0);
 
-	ret = bind(fd[0], addr1, addrlen1);
-	ASSERT_EQ(ret, 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);
+	}
 
-	ret = getsockname(fd[0], addr1, &addrlen1);
-	ASSERT_EQ(ret, 0);
+	if (i < 2 && reuse) {
+		ret = setsockopt(self->fd[i], SOL_SOCKET, reuse, &(int){1}, sizeof(int));
+		ASSERT_EQ(ret, 0);
+	}
 
-	((struct sockaddr_in *)addr2)->sin_port = ((struct sockaddr_in *)addr1)->sin_port;
+	self->addr[i].addr4.sin_port = self->addr[0].addr4.sin_port;
 
-	fd[1] = socket(addr2->sa_family, SOCK_STREAM, 0);
-	ASSERT_GT(fd[1], 0);
+	ret = bind(self->fd[i], &self->addr[i].addr, self->addrlen[i]);
 
-	ret = bind(fd[1], addr2, addrlen2);
-	if (expected_errno) {
-		ASSERT_EQ(ret, -1);
-		ASSERT_EQ(errno, expected_errno);
+	if (reuse) {
+		if (variant->expected_reuse_errno[i]) {
+			ASSERT_EQ(ret, -1);
+			ASSERT_EQ(errno, variant->expected_reuse_errno[i]);
+		} else {
+			ASSERT_EQ(ret, 0);
+		}
 	} else {
+		if (variant->expected_errno[i]) {
+			ASSERT_EQ(ret, -1);
+			ASSERT_EQ(errno, variant->expected_errno[i]);
+		} else {
+			ASSERT_EQ(ret, 0);
+		}
+	}
+
+	if (i == 0) {
+		ret = getsockname(self->fd[0], &self->addr[0].addr, &self->addrlen[0]);
 		ASSERT_EQ(ret, 0);
 	}
+}
 
-	close(fd[1]);
-	close(fd[0]);
+TEST_F(bind_wildcard, plain)
+{
+	int i;
+
+	for (i = 0; i < NR_SOCKETS; i++)
+		bind_socket(_metadata, self, variant, i, 0);
 }
 
-TEST_F(bind_wildcard, v4_v6)
+TEST_F(bind_wildcard, reuseaddr)
 {
-	bind_sockets(_metadata, self, variant->expected_errno,
-		     (struct sockaddr *)&self->addr4, sizeof(self->addr4),
-		     (struct sockaddr *)&self->addr6, sizeof(self->addr6));
+	int i;
+
+	for (i = 0; i < NR_SOCKETS; i++)
+		bind_socket(_metadata, self, variant, i, SO_REUSEADDR);
 }
 
-TEST_F(bind_wildcard, v6_v4)
+TEST_F(bind_wildcard, reuseport)
 {
-	bind_sockets(_metadata, self, variant->expected_errno,
-		     (struct sockaddr *)&self->addr6, sizeof(self->addr6),
-		     (struct sockaddr *)&self->addr4, sizeof(self->addr4));
+	int i;
+
+	for (i = 0; i < NR_SOCKETS; i++)
+		bind_socket(_metadata, self, variant, i, SO_REUSEPORT);
 }
 
 TEST_HARNESS_MAIN