`socket_inet_loopback`: Split off tests that need isolation in their own file.

This allows these tests, which can cause flakiness when run in the same network
namespace as the other `socket_inet_loopback` tests, to run as separate tests
in their own environment. It also means that all of the shards of those tests
can be more isolated from each other as well.

PiperOrigin-RevId: 380930198

9 files changed, 795 insertions, 772 deletions

diff --git a/test/syscalls/BUILD b/test/syscalls/BUILD
index 99743b14a..8fc96d7ba 100644
--- a/test/syscalls/BUILD
+++ b/test/syscalls/BUILD
@@ -648,6 +648,12 @@ syscall_test(
 syscall_test(
     size = "large",
     shard_count = most_shards,
+    test = "//test/syscalls/linux:socket_inet_loopback_isolated_test",
+)
+
+syscall_test(
+    size = "large",
+    shard_count = most_shards,
     # Takes too long for TSAN. Creates a lot of TCP sockets.
     tags = ["nogotsan"],
     test = "//test/syscalls/linux:socket_inet_loopback_nogotsan_test",
diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD
index d8b562e9d..112390569 100644
--- a/test/syscalls/linux/BUILD
+++ b/test/syscalls/linux/BUILD
@@ -9,6 +9,8 @@ exports_files(
     [
         "socket.cc",
         "socket_inet_loopback.cc",
+        "socket_inet_loopback_isolated.cc",
+        "socket_inet_loopback_test_params.h",
         "socket_ip_loopback_blocking.cc",
         "socket_ip_tcp_generic_loopback.cc",
         "socket_ip_tcp_loopback.cc",
@@ -3135,6 +3137,16 @@ cc_binary(
     ],
 )
 
+cc_library(
+    name = "socket_inet_loopback_test_params",
+    testonly = 1,
+    hdrs = ["socket_inet_loopback_test_params.h"],
+    deps = [
+        ":socket_test_util",
+        gtest,
+    ],
+)
+
 cc_binary(
     name = "socket_inet_loopback_test",
     testonly = 1,
@@ -3142,6 +3154,7 @@ cc_binary(
     linkstatic = 1,
     deps = [
         ":ip_socket_test_util",
+        ":socket_inet_loopback_test_params",
         ":socket_test_util",
         "//test/util:file_descriptor",
         "@com_google_absl//absl/memory",
@@ -3163,16 +3176,29 @@ cc_binary(
     linkstatic = 1,
     deps = [
         ":ip_socket_test_util",
+        ":socket_inet_loopback_test_params",
         ":socket_test_util",
         "//test/util:file_descriptor",
-        "@com_google_absl//absl/memory",
         "@com_google_absl//absl/strings",
         gtest,
         "//test/util:posix_error",
         "//test/util:save_util",
         "//test/util:test_main",
         "//test/util:test_util",
-        "//test/util:thread_util",
+    ],
+)
+
+cc_binary(
+    name = "socket_inet_loopback_isolated_test",
+    testonly = 1,
+    srcs = ["socket_inet_loopback_isolated.cc"],
+    linkstatic = 1,
+    deps = [
+        ":socket_inet_loopback_test_params",
+        ":socket_test_util",
+        gtest,
+        "//test/util:test_main",
+        "@com_google_absl//absl/time",
     ],
 )
 
diff --git a/test/syscalls/linux/socket_bind_to_device_distribution.cc b/test/syscalls/linux/socket_bind_to_device_distribution.cc
index 3b108cbd3..70b0b2742 100644
--- a/test/syscalls/linux/socket_bind_to_device_distribution.cc
+++ b/test/syscalls/linux/socket_bind_to_device_distribution.cc
@@ -77,34 +77,6 @@ class BindToDeviceDistributionTest
   }
 };
 
-PosixErrorOr<uint16_t> AddrPort(int family, sockaddr_storage const& addr) {
-  switch (family) {
-    case AF_INET:
-      return static_cast<uint16_t>(
-          reinterpret_cast<sockaddr_in const*>(&addr)->sin_port);
-    case AF_INET6:
-      return static_cast<uint16_t>(
-          reinterpret_cast<sockaddr_in6 const*>(&addr)->sin6_port);
-    default:
-      return PosixError(EINVAL,
-                        absl::StrCat("unknown socket family: ", family));
-  }
-}
-
-PosixError SetAddrPort(int family, sockaddr_storage* addr, uint16_t port) {
-  switch (family) {
-    case AF_INET:
-      reinterpret_cast<sockaddr_in*>(addr)->sin_port = port;
-      return NoError();
-    case AF_INET6:
-      reinterpret_cast<sockaddr_in6*>(addr)->sin6_port = port;
-      return NoError();
-    default:
-      return PosixError(EINVAL,
-                        absl::StrCat("unknown socket family: ", family));
-  }
-}
-
 // Binds sockets to different devices and then creates many TCP connections.
 // Checks that the distribution of connections received on the sockets matches
 // the expectation.
diff --git a/test/syscalls/linux/socket_inet_loopback.cc b/test/syscalls/linux/socket_inet_loopback.cc
index 6b369d5b7..badc42ec5 100644
--- a/test/syscalls/linux/socket_inet_loopback.cc
+++ b/test/syscalls/linux/socket_inet_loopback.cc
@@ -34,6 +34,7 @@
 #include "absl/time/clock.h"
 #include "absl/time/time.h"
 #include "test/syscalls/linux/ip_socket_test_util.h"
+#include "test/syscalls/linux/socket_inet_loopback_test_params.h"
 #include "test/syscalls/linux/socket_test_util.h"
 #include "test/util/file_descriptor.h"
 #include "test/util/posix_error.h"
@@ -48,45 +49,7 @@ namespace {
 
 using ::testing::Gt;
 
-PosixErrorOr<uint16_t> AddrPort(int family, sockaddr_storage const& addr) {
-  switch (family) {
-    case AF_INET:
-      return static_cast<uint16_t>(
-          reinterpret_cast<sockaddr_in const*>(&addr)->sin_port);
-    case AF_INET6:
-      return static_cast<uint16_t>(
-          reinterpret_cast<sockaddr_in6 const*>(&addr)->sin6_port);
-    default:
-      return PosixError(EINVAL,
-                        absl::StrCat("unknown socket family: ", family));
-  }
-}
-
-PosixError SetAddrPort(int family, sockaddr_storage* addr, uint16_t port) {
-  switch (family) {
-    case AF_INET:
-      reinterpret_cast<sockaddr_in*>(addr)->sin_port = port;
-      return NoError();
-    case AF_INET6:
-      reinterpret_cast<sockaddr_in6*>(addr)->sin6_port = port;
-      return NoError();
-    default:
-      return PosixError(EINVAL,
-                        absl::StrCat("unknown socket family: ", family));
-  }
-}
-
-struct TestParam {
-  TestAddress listener;
-  TestAddress connector;
-};
-
-std::string DescribeTestParam(::testing::TestParamInfo<TestParam> const& info) {
-  return absl::StrCat("Listen", info.param.listener.description, "_Connect",
-                      info.param.connector.description);
-}
-
-using SocketInetLoopbackTest = ::testing::TestWithParam<TestParam>;
+using SocketInetLoopbackTest = ::testing::TestWithParam<SocketInetTestParam>;
 
 TEST(BadSocketPairArgs, ValidateErrForBadCallsToSocketPair) {
   int fd[2] = {};
@@ -299,7 +262,7 @@ void tcpSimpleConnectTest(TestAddress const& listener,
 }
 
 TEST_P(SocketInetLoopbackTest, TCP) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -307,7 +270,7 @@ TEST_P(SocketInetLoopbackTest, TCP) {
 }
 
 TEST_P(SocketInetLoopbackTest, TCPListenUnbound) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -316,7 +279,7 @@ TEST_P(SocketInetLoopbackTest, TCPListenUnbound) {
 }
 
 TEST_P(SocketInetLoopbackTest, TCPListenShutdownListen) {
-  const auto& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   const TestAddress& listener = param.listener;
   const TestAddress& connector = param.connector;
@@ -362,7 +325,7 @@ TEST_P(SocketInetLoopbackTest, TCPListenShutdownListen) {
 }
 
 TEST_P(SocketInetLoopbackTest, TCPListenShutdown) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -430,7 +393,7 @@ TEST_P(SocketInetLoopbackTest, TCPListenShutdown) {
 }
 
 TEST_P(SocketInetLoopbackTest, TCPListenClose) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -477,7 +440,7 @@ TEST_P(SocketInetLoopbackTest, TCPListenClose) {
 
 // Test the protocol state information returned by TCPINFO.
 TEST_P(SocketInetLoopbackTest, TCPInfoState) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -546,7 +509,7 @@ TEST_P(SocketInetLoopbackTest, TCPInfoState) {
   ASSERT_THAT(close(conn_fd.release()), SyscallSucceeds());
 }
 
-void TestHangupDuringConnect(const TestParam& param,
+void TestHangupDuringConnect(const SocketInetTestParam& param,
                              void (*hangup)(FileDescriptor&)) {
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -609,7 +572,7 @@ TEST_P(SocketInetLoopbackTest, TCPListenShutdownDuringConnect) {
   });
 }
 
-void TestListenHangupConnectingRead(const TestParam& param,
+void TestListenHangupConnectingRead(const SocketInetTestParam& param,
                                     void (*hangup)(FileDescriptor&)) {
   constexpr int kTimeout = 10000;
 
@@ -718,7 +681,7 @@ TEST_P(SocketInetLoopbackTest, TCPListenShutdownConnectingRead) {
 
 // Test close of a non-blocking connecting socket.
 TEST_P(SocketInetLoopbackTest, TCPNonBlockingConnectClose) {
-  TestParam const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -793,7 +756,7 @@ TEST_P(SocketInetLoopbackTest, TCPNonBlockingConnectClose) {
 // queue because the queue is full are not correctly delivered after restore
 // causing the last accept to timeout on the restore.
 TEST_P(SocketInetLoopbackTest, TCPAcceptBacklogSizes) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -843,7 +806,7 @@ TEST_P(SocketInetLoopbackTest, TCPAcceptBacklogSizes) {
 // queue because the queue is full are not correctly delivered after restore
 // causing the last accept to timeout on the restore.
 TEST_P(SocketInetLoopbackTest, TCPBacklog) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -934,7 +897,7 @@ TEST_P(SocketInetLoopbackTest, TCPBacklog) {
 // queue because the queue is full are not correctly delivered after restore
 // causing the last accept to timeout on the restore.
 TEST_P(SocketInetLoopbackTest, TCPBacklogAcceptAll) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -1024,175 +987,12 @@ TEST_P(SocketInetLoopbackTest, TCPBacklogAcceptAll) {
   }
 }
 
-// TCPFinWait2Test creates a pair of connected sockets then closes one end to
-// trigger FIN_WAIT2 state for the closed endpoint. Then it binds the same local
-// IP/port on a new socket and tries to connect. The connect should fail w/
-// an EADDRINUSE. Then we wait till the FIN_WAIT2 timeout is over and try the
-// connect again with a new socket and this time it should succeed.
-//
-// TCP timers are not S/R today, this can cause this test to be flaky when run
-// under random S/R due to timer being reset on a restore.
-TEST_P(SocketInetLoopbackTest, TCPFinWait2Test) {
-  auto const& param = GetParam();
-  TestAddress const& listener = param.listener;
-  TestAddress const& connector = param.connector;
-
-  // Create the listening socket.
-  const FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(listener.family(), SOCK_STREAM, IPPROTO_TCP));
-  sockaddr_storage listen_addr = listener.addr;
-  ASSERT_THAT(
-      bind(listen_fd.get(), AsSockAddr(&listen_addr), listener.addr_len),
-      SyscallSucceeds());
-  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
-
-  // Get the port bound by the listening socket.
-  socklen_t addrlen = listener.addr_len;
-  ASSERT_THAT(getsockname(listen_fd.get(), AsSockAddr(&listen_addr), &addrlen),
-              SyscallSucceeds());
-
-  uint16_t const port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener.family(), listen_addr));
-
-  // Connect to the listening socket.
-  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
-
-  // Lower FIN_WAIT2 state to 5 seconds for test.
-  constexpr int kTCPLingerTimeout = 5;
-  EXPECT_THAT(setsockopt(conn_fd.get(), IPPROTO_TCP, TCP_LINGER2,
-                         &kTCPLingerTimeout, sizeof(kTCPLingerTimeout)),
-              SyscallSucceedsWithValue(0));
-
-  sockaddr_storage conn_addr = connector.addr;
-  ASSERT_NO_ERRNO(SetAddrPort(connector.family(), &conn_addr, port));
-  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
-                                  connector.addr_len),
-              SyscallSucceeds());
-
-  // Accept the connection.
-  auto accepted =
-      ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
-
-  // Get the address/port bound by the connecting socket.
-  sockaddr_storage conn_bound_addr;
-  socklen_t conn_addrlen = connector.addr_len;
-  ASSERT_THAT(
-      getsockname(conn_fd.get(), AsSockAddr(&conn_bound_addr), &conn_addrlen),
-      SyscallSucceeds());
-
-  // close the connecting FD to trigger FIN_WAIT2  on the connected fd.
-  conn_fd.reset();
-
-  // Now bind and connect a new socket.
-  const FileDescriptor conn_fd2 = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
-
-  // Disable cooperative saves after this point. As a save between the first
-  // bind/connect and the second one can cause the linger timeout timer to
-  // be restarted causing the final bind/connect to fail.
-  DisableSave ds;
-
-  ASSERT_THAT(bind(conn_fd2.get(), AsSockAddr(&conn_bound_addr), conn_addrlen),
-              SyscallFailsWithErrno(EADDRINUSE));
-
-  // Sleep for a little over the linger timeout to reduce flakiness in
-  // save/restore tests.
-  absl::SleepFor(absl::Seconds(kTCPLingerTimeout + 2));
-
-  ds.reset();
-
-  ASSERT_THAT(
-      RetryEINTR(connect)(conn_fd2.get(), AsSockAddr(&conn_addr), conn_addrlen),
-      SyscallSucceeds());
-}
-
-// TCPLinger2TimeoutAfterClose creates a pair of connected sockets
-// then closes one end to trigger FIN_WAIT2 state for the closed endpont.
-// It then sleeps for the TCP_LINGER2 timeout and verifies that bind/
-// connecting the same address succeeds.
-//
-// TCP timers are not S/R today, this can cause this test to be flaky when run
-// under random S/R due to timer being reset on a restore.
-TEST_P(SocketInetLoopbackTest, TCPLinger2TimeoutAfterClose) {
-  auto const& param = GetParam();
-  TestAddress const& listener = param.listener;
-  TestAddress const& connector = param.connector;
-
-  // Create the listening socket.
-  const FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(listener.family(), SOCK_STREAM, IPPROTO_TCP));
-  sockaddr_storage listen_addr = listener.addr;
-  ASSERT_THAT(
-      bind(listen_fd.get(), AsSockAddr(&listen_addr), listener.addr_len),
-      SyscallSucceeds());
-  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
-
-  // Get the port bound by the listening socket.
-  socklen_t addrlen = listener.addr_len;
-  ASSERT_THAT(getsockname(listen_fd.get(), AsSockAddr(&listen_addr), &addrlen),
-              SyscallSucceeds());
-
-  uint16_t const port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener.family(), listen_addr));
-
-  // Connect to the listening socket.
-  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
-
-  sockaddr_storage conn_addr = connector.addr;
-  ASSERT_NO_ERRNO(SetAddrPort(connector.family(), &conn_addr, port));
-  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
-                                  connector.addr_len),
-              SyscallSucceeds());
-
-  // Accept the connection.
-  auto accepted =
-      ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
-
-  // Get the address/port bound by the connecting socket.
-  sockaddr_storage conn_bound_addr;
-  socklen_t conn_addrlen = connector.addr_len;
-  ASSERT_THAT(
-      getsockname(conn_fd.get(), AsSockAddr(&conn_bound_addr), &conn_addrlen),
-      SyscallSucceeds());
-
-  // Disable cooperative saves after this point as TCP timers are not restored
-  // across a S/R.
-  {
-    DisableSave ds;
-    constexpr int kTCPLingerTimeout = 5;
-    EXPECT_THAT(setsockopt(conn_fd.get(), IPPROTO_TCP, TCP_LINGER2,
-                           &kTCPLingerTimeout, sizeof(kTCPLingerTimeout)),
-                SyscallSucceedsWithValue(0));
-
-    // close the connecting FD to trigger FIN_WAIT2  on the connected fd.
-    conn_fd.reset();
-
-    absl::SleepFor(absl::Seconds(kTCPLingerTimeout + 1));
-
-    // ds going out of scope will Re-enable S/R's since at this point the timer
-    // must have fired and cleaned up the endpoint.
-  }
-
-  // Now bind and connect a new socket and verify that we can immediately
-  // rebind the address bound by the conn_fd as it never entered TIME_WAIT.
-  const FileDescriptor conn_fd2 = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
-
-  ASSERT_THAT(bind(conn_fd2.get(), AsSockAddr(&conn_bound_addr), conn_addrlen),
-              SyscallSucceeds());
-  ASSERT_THAT(
-      RetryEINTR(connect)(conn_fd2.get(), AsSockAddr(&conn_addr), conn_addrlen),
-      SyscallSucceeds());
-}
-
 // TCPResetAfterClose creates a pair of connected sockets then closes
 // one end to trigger FIN_WAIT2 state for the closed endpoint verifies
 // that we generate RSTs for any new data after the socket is fully
 // closed.
 TEST_P(SocketInetLoopbackTest, TCPResetAfterClose) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -1252,198 +1052,8 @@ TEST_P(SocketInetLoopbackTest, TCPResetAfterClose) {
               SyscallSucceedsWithValue(0));
 }
 
-// setupTimeWaitClose sets up a socket endpoint in TIME_WAIT state.
-// Callers can choose to perform active close on either ends of the connection
-// and also specify if they want to enabled SO_REUSEADDR.
-void setupTimeWaitClose(const TestAddress* listener,
-                        const TestAddress* connector, bool reuse,
-                        bool accept_close, sockaddr_storage* listen_addr,
-                        sockaddr_storage* conn_bound_addr) {
-  // Create the listening socket.
-  FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(listener->family(), SOCK_STREAM, IPPROTO_TCP));
-  if (reuse) {
-    ASSERT_THAT(setsockopt(listen_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                           &kSockOptOn, sizeof(kSockOptOn)),
-                SyscallSucceeds());
-  }
-  ASSERT_THAT(
-      bind(listen_fd.get(), AsSockAddr(listen_addr), listener->addr_len),
-      SyscallSucceeds());
-  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
-
-  // Get the port bound by the listening socket.
-  socklen_t addrlen = listener->addr_len;
-  ASSERT_THAT(getsockname(listen_fd.get(), AsSockAddr(listen_addr), &addrlen),
-              SyscallSucceeds());
-
-  uint16_t const port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener->family(), *listen_addr));
-
-  // Connect to the listening socket.
-  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(connector->family(), SOCK_STREAM, IPPROTO_TCP));
-
-  // We disable saves after this point as a S/R causes the netstack seed
-  // to be regenerated which changes what ports/ISN is picked for a given
-  // tuple (src ip,src port, dst ip, dst port). This can cause the final
-  // SYN to use a sequence number that looks like one from the current
-  // connection in TIME_WAIT and will not be accepted causing the test
-  // to timeout.
-  //
-  // TODO(gvisor.dev/issue/940): S/R portSeed/portHint
-  DisableSave ds;
-
-  sockaddr_storage conn_addr = connector->addr;
-  ASSERT_NO_ERRNO(SetAddrPort(connector->family(), &conn_addr, port));
-  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
-                                  connector->addr_len),
-              SyscallSucceeds());
-
-  // Accept the connection.
-  auto accepted =
-      ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
-
-  // Get the address/port bound by the connecting socket.
-  socklen_t conn_addrlen = connector->addr_len;
-  ASSERT_THAT(
-      getsockname(conn_fd.get(), AsSockAddr(conn_bound_addr), &conn_addrlen),
-      SyscallSucceeds());
-
-  FileDescriptor active_closefd, passive_closefd;
-  if (accept_close) {
-    active_closefd = std::move(accepted);
-    passive_closefd = std::move(conn_fd);
-  } else {
-    active_closefd = std::move(conn_fd);
-    passive_closefd = std::move(accepted);
-  }
-
-  // shutdown to trigger TIME_WAIT.
-  ASSERT_THAT(shutdown(active_closefd.get(), SHUT_WR), SyscallSucceeds());
-  {
-    constexpr int kTimeout = 10000;
-    pollfd pfd = {
-        .fd = passive_closefd.get(),
-        .events = POLLIN,
-    };
-    ASSERT_THAT(poll(&pfd, 1, kTimeout), SyscallSucceedsWithValue(1));
-    ASSERT_EQ(pfd.revents, POLLIN);
-  }
-  ASSERT_THAT(shutdown(passive_closefd.get(), SHUT_WR), SyscallSucceeds());
-  {
-    constexpr int kTimeout = 10000;
-    constexpr int16_t want_events = POLLHUP;
-    pollfd pfd = {
-        .fd = active_closefd.get(),
-        .events = want_events,
-    };
-    ASSERT_THAT(poll(&pfd, 1, kTimeout), SyscallSucceedsWithValue(1));
-  }
-
-  // This sleep is needed to reduce flake to ensure that the passive-close
-  // ensures the state transitions to CLOSE from LAST_ACK.
-  absl::SleepFor(absl::Seconds(1));
-}
-
-// These tests are disabled under random save as the the restore run
-// results in the stack.Seed() being different which can cause
-// sequence number of final connect to be one that is considered
-// old and can cause the test to be flaky.
-//
-// Test re-binding of client and server bound addresses when the older
-// connection is in TIME_WAIT.
-TEST_P(SocketInetLoopbackTest, TCPPassiveCloseNoTimeWaitTest) {
-  auto const& param = GetParam();
-  sockaddr_storage listen_addr, conn_bound_addr;
-  listen_addr = param.listener.addr;
-  setupTimeWaitClose(&param.listener, &param.connector, false /*reuse*/,
-                     true /*accept_close*/, &listen_addr, &conn_bound_addr);
-
-  // Now bind a new socket and verify that we can immediately rebind the address
-  // bound by the conn_fd as it never entered TIME_WAIT.
-  const FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
-  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
-                   param.connector.addr_len),
-              SyscallSucceeds());
-
-  FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(param.listener.family(), SOCK_STREAM, IPPROTO_TCP));
-  ASSERT_THAT(
-      bind(listen_fd.get(), AsSockAddr(&listen_addr), param.listener.addr_len),
-      SyscallFailsWithErrno(EADDRINUSE));
-}
-
-TEST_P(SocketInetLoopbackTest, TCPPassiveCloseNoTimeWaitReuseTest) {
-  auto const& param = GetParam();
-  sockaddr_storage listen_addr, conn_bound_addr;
-  listen_addr = param.listener.addr;
-  setupTimeWaitClose(&param.listener, &param.connector, true /*reuse*/,
-                     true /*accept_close*/, &listen_addr, &conn_bound_addr);
-
-  FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(param.listener.family(), SOCK_STREAM, IPPROTO_TCP));
-  ASSERT_THAT(setsockopt(listen_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
-                         sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  ASSERT_THAT(
-      bind(listen_fd.get(), AsSockAddr(&listen_addr), param.listener.addr_len),
-      SyscallSucceeds());
-  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
-
-  // Now bind and connect  new socket and verify that we can immediately rebind
-  // the address bound by the conn_fd as it never entered TIME_WAIT.
-  const FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
-  ASSERT_THAT(setsockopt(conn_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
-                         sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
-                   param.connector.addr_len),
-              SyscallSucceeds());
-
-  uint16_t const port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(param.listener.family(), listen_addr));
-  sockaddr_storage conn_addr = param.connector.addr;
-  ASSERT_NO_ERRNO(SetAddrPort(param.connector.family(), &conn_addr, port));
-  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
-                                  param.connector.addr_len),
-              SyscallSucceeds());
-}
-
-TEST_P(SocketInetLoopbackTest, TCPActiveCloseTimeWaitTest) {
-  auto const& param = GetParam();
-  sockaddr_storage listen_addr, conn_bound_addr;
-  listen_addr = param.listener.addr;
-  setupTimeWaitClose(&param.listener, &param.connector, false /*reuse*/,
-                     false /*accept_close*/, &listen_addr, &conn_bound_addr);
-  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
-
-  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
-                   param.connector.addr_len),
-              SyscallFailsWithErrno(EADDRINUSE));
-}
-
-TEST_P(SocketInetLoopbackTest, TCPActiveCloseTimeWaitReuseTest) {
-  auto const& param = GetParam();
-  sockaddr_storage listen_addr, conn_bound_addr;
-  listen_addr = param.listener.addr;
-  setupTimeWaitClose(&param.listener, &param.connector, true /*reuse*/,
-                     false /*accept_close*/, &listen_addr, &conn_bound_addr);
-  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
-      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
-  ASSERT_THAT(setsockopt(conn_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
-                         sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
-                   param.connector.addr_len),
-              SyscallFailsWithErrno(EADDRINUSE));
-}
-
 TEST_P(SocketInetLoopbackTest, AcceptedInheritsTCPUserTimeout) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -1495,7 +1105,7 @@ TEST_P(SocketInetLoopbackTest, AcceptedInheritsTCPUserTimeout) {
 }
 
 TEST_P(SocketInetLoopbackTest, TCPAcceptAfterReset) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -1606,7 +1216,7 @@ TEST_P(SocketInetLoopbackTest, TCPDeferAccept) {
   // saved. Enable S/R issue is fixed.
   DisableSave ds;
 
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -1686,7 +1296,7 @@ TEST_P(SocketInetLoopbackTest, TCPDeferAcceptTimeout) {
   // saved. Enable S/R once issue is fixed.
   DisableSave ds;
 
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -1753,42 +1363,16 @@ TEST_P(SocketInetLoopbackTest, TCPDeferAcceptTimeout) {
       ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
 }
 
-INSTANTIATE_TEST_SUITE_P(
-    All, SocketInetLoopbackTest,
-    ::testing::Values(
-        // Listeners bound to IPv4 addresses refuse connections using IPv6
-        // addresses.
-        TestParam{V4Any(), V4Any()}, TestParam{V4Any(), V4Loopback()},
-        TestParam{V4Any(), V4MappedAny()},
-        TestParam{V4Any(), V4MappedLoopback()},
-        TestParam{V4Loopback(), V4Any()}, TestParam{V4Loopback(), V4Loopback()},
-        TestParam{V4Loopback(), V4MappedLoopback()},
-        TestParam{V4MappedAny(), V4Any()},
-        TestParam{V4MappedAny(), V4Loopback()},
-        TestParam{V4MappedAny(), V4MappedAny()},
-        TestParam{V4MappedAny(), V4MappedLoopback()},
-        TestParam{V4MappedLoopback(), V4Any()},
-        TestParam{V4MappedLoopback(), V4Loopback()},
-        TestParam{V4MappedLoopback(), V4MappedLoopback()},
-
-        // Listeners bound to IN6ADDR_ANY accept all connections.
-        TestParam{V6Any(), V4Any()}, TestParam{V6Any(), V4Loopback()},
-        TestParam{V6Any(), V4MappedAny()},
-        TestParam{V6Any(), V4MappedLoopback()}, TestParam{V6Any(), V6Any()},
-        TestParam{V6Any(), V6Loopback()},
-
-        // Listeners bound to IN6ADDR_LOOPBACK refuse connections using IPv4
-        // addresses.
-        TestParam{V6Loopback(), V6Any()},
-        TestParam{V6Loopback(), V6Loopback()}),
-    DescribeTestParam);
+INSTANTIATE_TEST_SUITE_P(All, SocketInetLoopbackTest,
+                         SocketInetLoopbackTestValues(),
+                         DescribeSocketInetTestParam);
 
-using SocketInetReusePortTest = ::testing::TestWithParam<TestParam>;
+using SocketInetReusePortTest = ::testing::TestWithParam<SocketInetTestParam>;
 
 // TODO(gvisor.dev/issue/940): Remove  when portHint/stack.Seed is
 // saved/restored.
 TEST_P(SocketInetReusePortTest, TcpPortReuseMultiThread) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -1898,7 +1482,7 @@ TEST_P(SocketInetReusePortTest, TcpPortReuseMultiThread) {
 }
 
 TEST_P(SocketInetReusePortTest, UdpPortReuseMultiThread) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -2009,7 +1593,7 @@ TEST_P(SocketInetReusePortTest, UdpPortReuseMultiThread) {
 }
 
 TEST_P(SocketInetReusePortTest, UdpPortReuseMultiThreadShort) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
 
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
@@ -2117,32 +1701,23 @@ INSTANTIATE_TEST_SUITE_P(
     ::testing::Values(
         // Listeners bound to IPv4 addresses refuse connections using IPv6
         // addresses.
-        TestParam{V4Any(), V4Loopback()},
-        TestParam{V4Loopback(), V4MappedLoopback()},
+        SocketInetTestParam{V4Any(), V4Loopback()},
+        SocketInetTestParam{V4Loopback(), V4MappedLoopback()},
 
         // Listeners bound to IN6ADDR_ANY accept all connections.
-        TestParam{V6Any(), V4Loopback()}, TestParam{V6Any(), V6Loopback()},
+        SocketInetTestParam{V6Any(), V4Loopback()},
+        SocketInetTestParam{V6Any(), V6Loopback()},
 
         // Listeners bound to IN6ADDR_LOOPBACK refuse connections using IPv4
         // addresses.
-        TestParam{V6Loopback(), V6Loopback()}),
-    DescribeTestParam);
-
-struct ProtocolTestParam {
-  std::string description;
-  int type;
-};
-
-std::string DescribeProtocolTestParam(
-    ::testing::TestParamInfo<ProtocolTestParam> const& info) {
-  return info.param.description;
-}
+        SocketInetTestParam{V6Loopback(), V6Loopback()}),
+    DescribeSocketInetTestParam);
 
 using SocketMultiProtocolInetLoopbackTest =
     ::testing::TestWithParam<ProtocolTestParam>;
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, V4MappedLoopbackOnlyReservesV4) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   for (int i = 0; true; i++) {
     // Bind the v4 loopback on a dual stack socket.
@@ -2191,7 +1766,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, V4MappedLoopbackOnlyReservesV4) {
 }
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, V4MappedAnyOnlyReservesV4) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   for (int i = 0; true; i++) {
     // Bind the v4 any on a dual stack socket.
@@ -2240,7 +1815,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, V4MappedAnyOnlyReservesV4) {
 }
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, DualStackV6AnyReservesEverything) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   // Bind the v6 any on a dual stack socket.
   TestAddress const& test_addr_dual = V6Any();
@@ -2303,7 +1878,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, DualStackV6AnyReservesEverything) {
 
 TEST_P(SocketMultiProtocolInetLoopbackTest,
        DualStackV6AnyReuseAddrDoesNotReserveV4Any) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   // Bind the v6 any on a dual stack socket.
   TestAddress const& test_addr_dual = V6Any();
@@ -2340,7 +1915,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest,
 
 TEST_P(SocketMultiProtocolInetLoopbackTest,
        DualStackV6AnyReuseAddrListenReservesV4Any) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   // Only TCP sockets are supported.
   SKIP_IF((param.type & SOCK_STREAM) == 0);
@@ -2383,7 +1958,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest,
 
 TEST_P(SocketMultiProtocolInetLoopbackTest,
        DualStackV6AnyWithListenReservesEverything) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   // Only TCP sockets are supported.
   SKIP_IF((param.type & SOCK_STREAM) == 0);
@@ -2450,7 +2025,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest,
 }
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, V6OnlyV6AnyReservesV6) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   for (int i = 0; true; i++) {
     // Bind the v6 any on a v6-only socket.
@@ -2503,7 +2078,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, V6OnlyV6AnyReservesV6) {
 }
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, V6EphemeralPortReserved) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   for (int i = 0; true; i++) {
     // Bind the v6 loopback on a dual stack socket.
@@ -2583,66 +2158,8 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, V6EphemeralPortReserved) {
   }
 }
 
-TEST_P(SocketMultiProtocolInetLoopbackTest, V6EphemeralPortReservedReuseAddr) {
-  auto const& param = GetParam();
-
-  // Bind the v6 loopback on a dual stack socket.
-  TestAddress const& test_addr = V6Loopback();
-  sockaddr_storage bound_addr = test_addr.addr;
-  const FileDescriptor bound_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(bind(bound_fd.get(), AsSockAddr(&bound_addr), test_addr.addr_len),
-              SyscallSucceeds());
-  ASSERT_THAT(setsockopt(bound_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
-                         sizeof(kSockOptOn)),
-              SyscallSucceeds());
-
-  // Listen iff TCP.
-  if (param.type == SOCK_STREAM) {
-    ASSERT_THAT(listen(bound_fd.get(), SOMAXCONN), SyscallSucceeds());
-  }
-
-  // Get the port that we bound.
-  socklen_t bound_addr_len = test_addr.addr_len;
-  ASSERT_THAT(
-      getsockname(bound_fd.get(), AsSockAddr(&bound_addr), &bound_addr_len),
-      SyscallSucceeds());
-
-  // Connect to bind an ephemeral port.
-  const FileDescriptor connected_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(setsockopt(connected_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                         &kSockOptOn, sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  ASSERT_THAT(RetryEINTR(connect)(connected_fd.get(), AsSockAddr(&bound_addr),
-                                  bound_addr_len),
-              SyscallSucceeds());
-
-  // Get the ephemeral port.
-  sockaddr_storage connected_addr = {};
-  socklen_t connected_addr_len = sizeof(connected_addr);
-  ASSERT_THAT(getsockname(connected_fd.get(), AsSockAddr(&connected_addr),
-                          &connected_addr_len),
-              SyscallSucceeds());
-  uint16_t const ephemeral_port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(test_addr.family(), connected_addr));
-
-  // Verify that we actually got an ephemeral port.
-  ASSERT_NE(ephemeral_port, 0);
-
-  // Verify that the ephemeral port is not reserved.
-  const FileDescriptor checking_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(setsockopt(checking_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                         &kSockOptOn, sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  EXPECT_THAT(
-      bind(checking_fd.get(), AsSockAddr(&connected_addr), connected_addr_len),
-      SyscallSucceeds());
-}
-
 TEST_P(SocketMultiProtocolInetLoopbackTest, V4MappedEphemeralPortReserved) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   for (int i = 0; true; i++) {
     // Bind the v4 loopback on a dual stack socket.
@@ -2754,68 +2271,8 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, V4MappedEphemeralPortReserved) {
   }
 }
 
-TEST_P(SocketMultiProtocolInetLoopbackTest,
-       V4MappedEphemeralPortReservedResueAddr) {
-  auto const& param = GetParam();
-
-  // Bind the v4 loopback on a dual stack socket.
-  TestAddress const& test_addr = V4MappedLoopback();
-  sockaddr_storage bound_addr = test_addr.addr;
-  const FileDescriptor bound_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(bind(bound_fd.get(), AsSockAddr(&bound_addr), test_addr.addr_len),
-              SyscallSucceeds());
-
-  ASSERT_THAT(setsockopt(bound_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
-                         sizeof(kSockOptOn)),
-              SyscallSucceeds());
-
-  // Listen iff TCP.
-  if (param.type == SOCK_STREAM) {
-    ASSERT_THAT(listen(bound_fd.get(), SOMAXCONN), SyscallSucceeds());
-  }
-
-  // Get the port that we bound.
-  socklen_t bound_addr_len = test_addr.addr_len;
-  ASSERT_THAT(
-      getsockname(bound_fd.get(), AsSockAddr(&bound_addr), &bound_addr_len),
-      SyscallSucceeds());
-
-  // Connect to bind an ephemeral port.
-  const FileDescriptor connected_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(setsockopt(connected_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                         &kSockOptOn, sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  ASSERT_THAT(RetryEINTR(connect)(connected_fd.get(), AsSockAddr(&bound_addr),
-                                  bound_addr_len),
-              SyscallSucceeds());
-
-  // Get the ephemeral port.
-  sockaddr_storage connected_addr = {};
-  socklen_t connected_addr_len = sizeof(connected_addr);
-  ASSERT_THAT(getsockname(connected_fd.get(), AsSockAddr(&connected_addr),
-                          &connected_addr_len),
-              SyscallSucceeds());
-  uint16_t const ephemeral_port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(test_addr.family(), connected_addr));
-
-  // Verify that we actually got an ephemeral port.
-  ASSERT_NE(ephemeral_port, 0);
-
-  // Verify that the ephemeral port is not reserved.
-  const FileDescriptor checking_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(setsockopt(checking_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                         &kSockOptOn, sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  EXPECT_THAT(
-      bind(checking_fd.get(), AsSockAddr(&connected_addr), connected_addr_len),
-      SyscallSucceeds());
-}
-
 TEST_P(SocketMultiProtocolInetLoopbackTest, V4EphemeralPortReserved) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
 
   for (int i = 0; true; i++) {
     // Bind the v4 loopback on a v4 socket.
@@ -2928,71 +2385,9 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, V4EphemeralPortReserved) {
   }
 }
 
-TEST_P(SocketMultiProtocolInetLoopbackTest, V4EphemeralPortReservedReuseAddr) {
-  auto const& param = GetParam();
-
-  // Bind the v4 loopback on a v4 socket.
-  TestAddress const& test_addr = V4Loopback();
-  sockaddr_storage bound_addr = test_addr.addr;
-  const FileDescriptor bound_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-
-  ASSERT_THAT(setsockopt(bound_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
-                         sizeof(kSockOptOn)),
-              SyscallSucceeds());
-
-  ASSERT_THAT(bind(bound_fd.get(), AsSockAddr(&bound_addr), test_addr.addr_len),
-              SyscallSucceeds());
-
-  // Listen iff TCP.
-  if (param.type == SOCK_STREAM) {
-    ASSERT_THAT(listen(bound_fd.get(), SOMAXCONN), SyscallSucceeds());
-  }
-
-  // Get the port that we bound.
-  socklen_t bound_addr_len = test_addr.addr_len;
-  ASSERT_THAT(
-      getsockname(bound_fd.get(), AsSockAddr(&bound_addr), &bound_addr_len),
-      SyscallSucceeds());
-
-  // Connect to bind an ephemeral port.
-  const FileDescriptor connected_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-
-  ASSERT_THAT(setsockopt(connected_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                         &kSockOptOn, sizeof(kSockOptOn)),
-              SyscallSucceeds());
-
-  ASSERT_THAT(RetryEINTR(connect)(connected_fd.get(), AsSockAddr(&bound_addr),
-                                  bound_addr_len),
-              SyscallSucceeds());
-
-  // Get the ephemeral port.
-  sockaddr_storage connected_addr = {};
-  socklen_t connected_addr_len = sizeof(connected_addr);
-  ASSERT_THAT(getsockname(connected_fd.get(), AsSockAddr(&connected_addr),
-                          &connected_addr_len),
-              SyscallSucceeds());
-  uint16_t const ephemeral_port =
-      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(test_addr.family(), connected_addr));
-
-  // Verify that we actually got an ephemeral port.
-  ASSERT_NE(ephemeral_port, 0);
-
-  // Verify that the ephemeral port is not reserved.
-  const FileDescriptor checking_fd =
-      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
-  ASSERT_THAT(setsockopt(checking_fd.get(), SOL_SOCKET, SO_REUSEADDR,
-                         &kSockOptOn, sizeof(kSockOptOn)),
-              SyscallSucceeds());
-  EXPECT_THAT(
-      bind(checking_fd.get(), AsSockAddr(&connected_addr), connected_addr_len),
-      SyscallSucceeds());
-}
-
 TEST_P(SocketMultiProtocolInetLoopbackTest,
        MultipleBindsAllowedNoListeningReuseAddr) {
-  const auto& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
   // UDP sockets are allowed to bind/listen on the port w/ SO_REUSEADDR, for TCP
   // this is only permitted if there is no other listening socket.
   SKIP_IF(param.type != SOCK_STREAM);
@@ -3027,7 +2422,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest,
 }
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, PortReuseTwoSockets) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
   TestAddress const& test_addr = V4Loopback();
   sockaddr_storage addr = test_addr.addr;
 
@@ -3080,7 +2475,7 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, PortReuseTwoSockets) {
 // closed, we can bind a different socket to the same address without needing
 // REUSEPORT.
 TEST_P(SocketMultiProtocolInetLoopbackTest, NoReusePortFollowingReusePort) {
-  auto const& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
   TestAddress const& test_addr = V4Loopback();
   sockaddr_storage addr = test_addr.addr;
 
@@ -3107,11 +2502,8 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, NoReusePortFollowingReusePort) {
   ASSERT_THAT(bind(fd, AsSockAddr(&addr), addrlen), SyscallSucceeds());
 }
 
-INSTANTIATE_TEST_SUITE_P(
-    AllFamilies, SocketMultiProtocolInetLoopbackTest,
-    ::testing::Values(ProtocolTestParam{"TCP", SOCK_STREAM},
-                      ProtocolTestParam{"UDP", SOCK_DGRAM}),
-    DescribeProtocolTestParam);
+INSTANTIATE_TEST_SUITE_P(AllFamilies, SocketMultiProtocolInetLoopbackTest,
+                         ProtocolTestValues(), DescribeProtocolTestParam);
 
 }  // namespace
 
diff --git a/test/syscalls/linux/socket_inet_loopback_isolated.cc b/test/syscalls/linux/socket_inet_loopback_isolated.cc
new file mode 100644
index 000000000..ccb016726
--- /dev/null
+++ b/test/syscalls/linux/socket_inet_loopback_isolated.cc
@@ -0,0 +1,488 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <netinet/tcp.h>
+
+#include "gtest/gtest.h"
+#include "absl/time/clock.h"
+#include "absl/time/time.h"
+#include "test/syscalls/linux/socket_inet_loopback_test_params.h"
+#include "test/syscalls/linux/socket_test_util.h"
+
+// Unit tests in this file will run in their own network namespace.
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+using SocketInetLoopbackIsolatedTest =
+    ::testing::TestWithParam<SocketInetTestParam>;
+
+TEST_P(SocketInetLoopbackIsolatedTest, TCPActiveCloseTimeWaitTest) {
+  SocketInetTestParam const& param = GetParam();
+  sockaddr_storage listen_addr, conn_bound_addr;
+  listen_addr = param.listener.addr;
+  SetupTimeWaitClose(&param.listener, &param.connector, false /*reuse*/,
+                     false /*accept_close*/, &listen_addr, &conn_bound_addr);
+  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
+
+  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
+                   param.connector.addr_len),
+              SyscallFailsWithErrno(EADDRINUSE));
+}
+
+TEST_P(SocketInetLoopbackIsolatedTest, TCPActiveCloseTimeWaitReuseTest) {
+  SocketInetTestParam const& param = GetParam();
+  sockaddr_storage listen_addr, conn_bound_addr;
+  listen_addr = param.listener.addr;
+  SetupTimeWaitClose(&param.listener, &param.connector, true /*reuse*/,
+                     false /*accept_close*/, &listen_addr, &conn_bound_addr);
+  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
+  ASSERT_THAT(setsockopt(conn_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
+                         sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
+                   param.connector.addr_len),
+              SyscallFailsWithErrno(EADDRINUSE));
+}
+
+// These tests are disabled under random save as the restore run
+// results in the stack.Seed() being different which can cause
+// sequence number of final connect to be one that is considered
+// old and can cause the test to be flaky.
+//
+// Test re-binding of client and server bound addresses when the older
+// connection is in TIME_WAIT.
+TEST_P(SocketInetLoopbackIsolatedTest, TCPPassiveCloseNoTimeWaitTest) {
+  SocketInetTestParam const& param = GetParam();
+  sockaddr_storage listen_addr, conn_bound_addr;
+  listen_addr = param.listener.addr;
+  SetupTimeWaitClose(&param.listener, &param.connector, false /*reuse*/,
+                     true /*accept_close*/, &listen_addr, &conn_bound_addr);
+
+  // Now bind a new socket and verify that we can immediately rebind the address
+  // bound by the conn_fd as it never entered TIME_WAIT.
+  const FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
+  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
+                   param.connector.addr_len),
+              SyscallSucceeds());
+
+  FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(param.listener.family(), SOCK_STREAM, IPPROTO_TCP));
+  ASSERT_THAT(
+      bind(listen_fd.get(), AsSockAddr(&listen_addr), param.listener.addr_len),
+      SyscallFailsWithErrno(EADDRINUSE));
+}
+
+TEST_P(SocketInetLoopbackIsolatedTest, TCPPassiveCloseNoTimeWaitReuseTest) {
+  SocketInetTestParam const& param = GetParam();
+  sockaddr_storage listen_addr, conn_bound_addr;
+  listen_addr = param.listener.addr;
+  SetupTimeWaitClose(&param.listener, &param.connector, true /*reuse*/,
+                     true /*accept_close*/, &listen_addr, &conn_bound_addr);
+
+  FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(param.listener.family(), SOCK_STREAM, IPPROTO_TCP));
+  ASSERT_THAT(setsockopt(listen_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
+                         sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  ASSERT_THAT(
+      bind(listen_fd.get(), AsSockAddr(&listen_addr), param.listener.addr_len),
+      SyscallSucceeds());
+  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
+
+  // Now bind and connect  new socket and verify that we can immediately rebind
+  // the address bound by the conn_fd as it never entered TIME_WAIT.
+  const FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(param.connector.family(), SOCK_STREAM, IPPROTO_TCP));
+  ASSERT_THAT(setsockopt(conn_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
+                         sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  ASSERT_THAT(bind(conn_fd.get(), AsSockAddr(&conn_bound_addr),
+                   param.connector.addr_len),
+              SyscallSucceeds());
+
+  uint16_t const port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(param.listener.family(), listen_addr));
+  sockaddr_storage conn_addr = param.connector.addr;
+  ASSERT_NO_ERRNO(SetAddrPort(param.connector.family(), &conn_addr, port));
+  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
+                                  param.connector.addr_len),
+              SyscallSucceeds());
+}
+
+// TCPFinWait2Test creates a pair of connected sockets then closes one end to
+// trigger FIN_WAIT2 state for the closed endpoint. Then it binds the same local
+// IP/port on a new socket and tries to connect. The connect should fail w/
+// an EADDRINUSE. Then we wait till the FIN_WAIT2 timeout is over and try the
+// connect again with a new socket and this time it should succeed.
+//
+// TCP timers are not S/R today, this can cause this test to be flaky when run
+// under random S/R due to timer being reset on a restore.
+TEST_P(SocketInetLoopbackIsolatedTest, TCPFinWait2Test) {
+  SocketInetTestParam const& param = GetParam();
+  TestAddress const& listener = param.listener;
+  TestAddress const& connector = param.connector;
+
+  // Create the listening socket.
+  const FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(listener.family(), SOCK_STREAM, IPPROTO_TCP));
+  sockaddr_storage listen_addr = listener.addr;
+  ASSERT_THAT(
+      bind(listen_fd.get(), AsSockAddr(&listen_addr), listener.addr_len),
+      SyscallSucceeds());
+  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
+
+  // Get the port bound by the listening socket.
+  socklen_t addrlen = listener.addr_len;
+  ASSERT_THAT(getsockname(listen_fd.get(), AsSockAddr(&listen_addr), &addrlen),
+              SyscallSucceeds());
+
+  uint16_t const port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener.family(), listen_addr));
+
+  // Connect to the listening socket.
+  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
+
+  // Lower FIN_WAIT2 state to 5 seconds for test.
+  constexpr int kTCPLingerTimeout = 5;
+  EXPECT_THAT(setsockopt(conn_fd.get(), IPPROTO_TCP, TCP_LINGER2,
+                         &kTCPLingerTimeout, sizeof(kTCPLingerTimeout)),
+              SyscallSucceedsWithValue(0));
+
+  sockaddr_storage conn_addr = connector.addr;
+  ASSERT_NO_ERRNO(SetAddrPort(connector.family(), &conn_addr, port));
+  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
+                                  connector.addr_len),
+              SyscallSucceeds());
+
+  // Accept the connection.
+  auto accepted =
+      ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
+
+  // Get the address/port bound by the connecting socket.
+  sockaddr_storage conn_bound_addr;
+  socklen_t conn_addrlen = connector.addr_len;
+  ASSERT_THAT(
+      getsockname(conn_fd.get(), AsSockAddr(&conn_bound_addr), &conn_addrlen),
+      SyscallSucceeds());
+
+  // close the connecting FD to trigger FIN_WAIT2  on the connected fd.
+  conn_fd.reset();
+
+  // Now bind and connect a new socket.
+  const FileDescriptor conn_fd2 = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
+
+  // Disable cooperative saves after this point. As a save between the first
+  // bind/connect and the second one can cause the linger timeout timer to
+  // be restarted causing the final bind/connect to fail.
+  DisableSave ds;
+
+  ASSERT_THAT(bind(conn_fd2.get(), AsSockAddr(&conn_bound_addr), conn_addrlen),
+              SyscallFailsWithErrno(EADDRINUSE));
+
+  // Sleep for a little over the linger timeout to reduce flakiness in
+  // save/restore tests.
+  absl::SleepFor(absl::Seconds(kTCPLingerTimeout + 2));
+
+  ds.reset();
+
+  ASSERT_THAT(
+      RetryEINTR(connect)(conn_fd2.get(), AsSockAddr(&conn_addr), conn_addrlen),
+      SyscallSucceeds());
+}
+
+// TCPLinger2TimeoutAfterClose creates a pair of connected sockets
+// then closes one end to trigger FIN_WAIT2 state for the closed endpoint.
+// It then sleeps for the TCP_LINGER2 timeout and verifies that bind/
+// connecting the same address succeeds.
+//
+// TCP timers are not S/R today, this can cause this test to be flaky when run
+// under random S/R due to timer being reset on a restore.
+TEST_P(SocketInetLoopbackIsolatedTest, TCPLinger2TimeoutAfterClose) {
+  SocketInetTestParam const& param = GetParam();
+  TestAddress const& listener = param.listener;
+  TestAddress const& connector = param.connector;
+
+  // Create the listening socket.
+  const FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(listener.family(), SOCK_STREAM, IPPROTO_TCP));
+  sockaddr_storage listen_addr = listener.addr;
+  ASSERT_THAT(
+      bind(listen_fd.get(), AsSockAddr(&listen_addr), listener.addr_len),
+      SyscallSucceeds());
+  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
+
+  // Get the port bound by the listening socket.
+  socklen_t addrlen = listener.addr_len;
+  ASSERT_THAT(getsockname(listen_fd.get(), AsSockAddr(&listen_addr), &addrlen),
+              SyscallSucceeds());
+
+  uint16_t const port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener.family(), listen_addr));
+
+  // Connect to the listening socket.
+  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
+
+  sockaddr_storage conn_addr = connector.addr;
+  ASSERT_NO_ERRNO(SetAddrPort(connector.family(), &conn_addr, port));
+  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
+                                  connector.addr_len),
+              SyscallSucceeds());
+
+  // Accept the connection.
+  auto accepted =
+      ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
+
+  // Get the address/port bound by the connecting socket.
+  sockaddr_storage conn_bound_addr;
+  socklen_t conn_addrlen = connector.addr_len;
+  ASSERT_THAT(
+      getsockname(conn_fd.get(), AsSockAddr(&conn_bound_addr), &conn_addrlen),
+      SyscallSucceeds());
+
+  // Disable cooperative saves after this point as TCP timers are not restored
+  // across a S/R.
+  {
+    DisableSave ds;
+    constexpr int kTCPLingerTimeout = 5;
+    EXPECT_THAT(setsockopt(conn_fd.get(), IPPROTO_TCP, TCP_LINGER2,
+                           &kTCPLingerTimeout, sizeof(kTCPLingerTimeout)),
+                SyscallSucceedsWithValue(0));
+
+    // close the connecting FD to trigger FIN_WAIT2  on the connected fd.
+    conn_fd.reset();
+
+    absl::SleepFor(absl::Seconds(kTCPLingerTimeout + 1));
+
+    // ds going out of scope will Re-enable S/R's since at this point the timer
+    // must have fired and cleaned up the endpoint.
+  }
+
+  // Now bind and connect a new socket and verify that we can immediately
+  // rebind the address bound by the conn_fd as it never entered TIME_WAIT.
+  const FileDescriptor conn_fd2 = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(connector.family(), SOCK_STREAM, IPPROTO_TCP));
+
+  ASSERT_THAT(bind(conn_fd2.get(), AsSockAddr(&conn_bound_addr), conn_addrlen),
+              SyscallSucceeds());
+  ASSERT_THAT(
+      RetryEINTR(connect)(conn_fd2.get(), AsSockAddr(&conn_addr), conn_addrlen),
+      SyscallSucceeds());
+}
+
+INSTANTIATE_TEST_SUITE_P(All, SocketInetLoopbackIsolatedTest,
+                         SocketInetLoopbackTestValues(),
+                         DescribeSocketInetTestParam);
+
+using SocketMultiProtocolInetLoopbackIsolatedTest =
+    ::testing::TestWithParam<ProtocolTestParam>;
+
+TEST_P(SocketMultiProtocolInetLoopbackIsolatedTest,
+       V4EphemeralPortReservedReuseAddr) {
+  ProtocolTestParam const& param = GetParam();
+
+  // Bind the v4 loopback on a v4 socket.
+  TestAddress const& test_addr = V4Loopback();
+  sockaddr_storage bound_addr = test_addr.addr;
+  const FileDescriptor bound_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+
+  ASSERT_THAT(setsockopt(bound_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
+                         sizeof(kSockOptOn)),
+              SyscallSucceeds());
+
+  ASSERT_THAT(bind(bound_fd.get(), AsSockAddr(&bound_addr), test_addr.addr_len),
+              SyscallSucceeds());
+
+  // Listen iff TCP.
+  if (param.type == SOCK_STREAM) {
+    ASSERT_THAT(listen(bound_fd.get(), SOMAXCONN), SyscallSucceeds());
+  }
+
+  // Get the port that we bound.
+  socklen_t bound_addr_len = test_addr.addr_len;
+  ASSERT_THAT(
+      getsockname(bound_fd.get(), AsSockAddr(&bound_addr), &bound_addr_len),
+      SyscallSucceeds());
+
+  // Connect to bind an ephemeral port.
+  const FileDescriptor connected_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+
+  ASSERT_THAT(setsockopt(connected_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+
+  ASSERT_THAT(RetryEINTR(connect)(connected_fd.get(), AsSockAddr(&bound_addr),
+                                  bound_addr_len),
+              SyscallSucceeds());
+
+  // Get the ephemeral port.
+  sockaddr_storage connected_addr = {};
+  socklen_t connected_addr_len = sizeof(connected_addr);
+  ASSERT_THAT(getsockname(connected_fd.get(), AsSockAddr(&connected_addr),
+                          &connected_addr_len),
+              SyscallSucceeds());
+  uint16_t const ephemeral_port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(test_addr.family(), connected_addr));
+
+  // Verify that we actually got an ephemeral port.
+  ASSERT_NE(ephemeral_port, 0);
+
+  // Verify that the ephemeral port is not reserved.
+  const FileDescriptor checking_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(setsockopt(checking_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  EXPECT_THAT(
+      bind(checking_fd.get(), AsSockAddr(&connected_addr), connected_addr_len),
+      SyscallSucceeds());
+}
+
+TEST_P(SocketMultiProtocolInetLoopbackIsolatedTest,
+       V4MappedEphemeralPortReservedReuseAddr) {
+  ProtocolTestParam const& param = GetParam();
+
+  // Bind the v4 loopback on a dual stack socket.
+  TestAddress const& test_addr = V4MappedLoopback();
+  sockaddr_storage bound_addr = test_addr.addr;
+  const FileDescriptor bound_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(bind(bound_fd.get(), AsSockAddr(&bound_addr), test_addr.addr_len),
+              SyscallSucceeds());
+
+  ASSERT_THAT(setsockopt(bound_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
+                         sizeof(kSockOptOn)),
+              SyscallSucceeds());
+
+  // Listen iff TCP.
+  if (param.type == SOCK_STREAM) {
+    ASSERT_THAT(listen(bound_fd.get(), SOMAXCONN), SyscallSucceeds());
+  }
+
+  // Get the port that we bound.
+  socklen_t bound_addr_len = test_addr.addr_len;
+  ASSERT_THAT(
+      getsockname(bound_fd.get(), AsSockAddr(&bound_addr), &bound_addr_len),
+      SyscallSucceeds());
+
+  // Connect to bind an ephemeral port.
+  const FileDescriptor connected_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(setsockopt(connected_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  ASSERT_THAT(RetryEINTR(connect)(connected_fd.get(), AsSockAddr(&bound_addr),
+                                  bound_addr_len),
+              SyscallSucceeds());
+
+  // Get the ephemeral port.
+  sockaddr_storage connected_addr = {};
+  socklen_t connected_addr_len = sizeof(connected_addr);
+  ASSERT_THAT(getsockname(connected_fd.get(), AsSockAddr(&connected_addr),
+                          &connected_addr_len),
+              SyscallSucceeds());
+  uint16_t const ephemeral_port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(test_addr.family(), connected_addr));
+
+  // Verify that we actually got an ephemeral port.
+  ASSERT_NE(ephemeral_port, 0);
+
+  // Verify that the ephemeral port is not reserved.
+  const FileDescriptor checking_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(setsockopt(checking_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  EXPECT_THAT(
+      bind(checking_fd.get(), AsSockAddr(&connected_addr), connected_addr_len),
+      SyscallSucceeds());
+}
+
+TEST_P(SocketMultiProtocolInetLoopbackIsolatedTest,
+       V6EphemeralPortReservedReuseAddr) {
+  ProtocolTestParam const& param = GetParam();
+
+  // Bind the v6 loopback on a dual stack socket.
+  TestAddress const& test_addr = V6Loopback();
+  sockaddr_storage bound_addr = test_addr.addr;
+  const FileDescriptor bound_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(bind(bound_fd.get(), AsSockAddr(&bound_addr), test_addr.addr_len),
+              SyscallSucceeds());
+  ASSERT_THAT(setsockopt(bound_fd.get(), SOL_SOCKET, SO_REUSEADDR, &kSockOptOn,
+                         sizeof(kSockOptOn)),
+              SyscallSucceeds());
+
+  // Listen iff TCP.
+  if (param.type == SOCK_STREAM) {
+    ASSERT_THAT(listen(bound_fd.get(), SOMAXCONN), SyscallSucceeds());
+  }
+
+  // Get the port that we bound.
+  socklen_t bound_addr_len = test_addr.addr_len;
+  ASSERT_THAT(
+      getsockname(bound_fd.get(), AsSockAddr(&bound_addr), &bound_addr_len),
+      SyscallSucceeds());
+
+  // Connect to bind an ephemeral port.
+  const FileDescriptor connected_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(setsockopt(connected_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  ASSERT_THAT(RetryEINTR(connect)(connected_fd.get(), AsSockAddr(&bound_addr),
+                                  bound_addr_len),
+              SyscallSucceeds());
+
+  // Get the ephemeral port.
+  sockaddr_storage connected_addr = {};
+  socklen_t connected_addr_len = sizeof(connected_addr);
+  ASSERT_THAT(getsockname(connected_fd.get(), AsSockAddr(&connected_addr),
+                          &connected_addr_len),
+              SyscallSucceeds());
+  uint16_t const ephemeral_port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(test_addr.family(), connected_addr));
+
+  // Verify that we actually got an ephemeral port.
+  ASSERT_NE(ephemeral_port, 0);
+
+  // Verify that the ephemeral port is not reserved.
+  const FileDescriptor checking_fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Socket(test_addr.family(), param.type, 0));
+  ASSERT_THAT(setsockopt(checking_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+  EXPECT_THAT(
+      bind(checking_fd.get(), AsSockAddr(&connected_addr), connected_addr_len),
+      SyscallSucceeds());
+}
+
+INSTANTIATE_TEST_SUITE_P(AllFamilies,
+                         SocketMultiProtocolInetLoopbackIsolatedTest,
+                         ProtocolTestValues(), DescribeProtocolTestParam);
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor
diff --git a/test/syscalls/linux/socket_inet_loopback_nogotsan.cc b/test/syscalls/linux/socket_inet_loopback_nogotsan.cc
index 601ae107b..b131213d4 100644
--- a/test/syscalls/linux/socket_inet_loopback_nogotsan.cc
+++ b/test/syscalls/linux/socket_inet_loopback_nogotsan.cc
@@ -27,6 +27,7 @@
 #include "gtest/gtest.h"
 #include "absl/strings/str_cat.h"
 #include "test/syscalls/linux/ip_socket_test_util.h"
+#include "test/syscalls/linux/socket_inet_loopback_test_params.h"
 #include "test/syscalls/linux/socket_test_util.h"
 #include "test/util/file_descriptor.h"
 #include "test/util/posix_error.h"
@@ -38,47 +39,7 @@ namespace testing {
 
 namespace {
 
-using ::testing::Gt;
-
-PosixErrorOr<uint16_t> AddrPort(int family, sockaddr_storage const& addr) {
-  switch (family) {
-    case AF_INET:
-      return static_cast<uint16_t>(
-          reinterpret_cast<sockaddr_in const*>(&addr)->sin_port);
-    case AF_INET6:
-      return static_cast<uint16_t>(
-          reinterpret_cast<sockaddr_in6 const*>(&addr)->sin6_port);
-    default:
-      return PosixError(EINVAL,
-                        absl::StrCat("unknown socket family: ", family));
-  }
-}
-
-PosixError SetAddrPort(int family, sockaddr_storage* addr, uint16_t port) {
-  switch (family) {
-    case AF_INET:
-      reinterpret_cast<sockaddr_in*>(addr)->sin_port = port;
-      return NoError();
-    case AF_INET6:
-      reinterpret_cast<sockaddr_in6*>(addr)->sin6_port = port;
-      return NoError();
-    default:
-      return PosixError(EINVAL,
-                        absl::StrCat("unknown socket family: ", family));
-  }
-}
-
-struct TestParam {
-  TestAddress listener;
-  TestAddress connector;
-};
-
-std::string DescribeTestParam(::testing::TestParamInfo<TestParam> const& info) {
-  return absl::StrCat("Listen", info.param.listener.description, "_Connect",
-                      info.param.connector.description);
-}
-
-using SocketInetLoopbackTest = ::testing::TestWithParam<TestParam>;
+using SocketInetLoopbackTest = ::testing::TestWithParam<SocketInetTestParam>;
 
 // This test verifies that connect returns EADDRNOTAVAIL if all local ephemeral
 // ports are already in use for a given destination ip/port.
@@ -87,7 +48,7 @@ using SocketInetLoopbackTest = ::testing::TestWithParam<TestParam>;
 //
 // FIXME(b/162475855): This test is failing reliably.
 TEST_P(SocketInetLoopbackTest, DISABLED_TestTCPPortExhaustion) {
-  auto const& param = GetParam();
+  SocketInetTestParam const& param = GetParam();
   TestAddress const& listener = param.listener;
   TestAddress const& connector = param.connector;
 
@@ -136,51 +97,15 @@ TEST_P(SocketInetLoopbackTest, DISABLED_TestTCPPortExhaustion) {
   }
 }
 
-INSTANTIATE_TEST_SUITE_P(
-    All, SocketInetLoopbackTest,
-    ::testing::Values(
-        // Listeners bound to IPv4 addresses refuse connections using IPv6
-        // addresses.
-        TestParam{V4Any(), V4Any()}, TestParam{V4Any(), V4Loopback()},
-        TestParam{V4Any(), V4MappedAny()},
-        TestParam{V4Any(), V4MappedLoopback()},
-        TestParam{V4Loopback(), V4Any()}, TestParam{V4Loopback(), V4Loopback()},
-        TestParam{V4Loopback(), V4MappedLoopback()},
-        TestParam{V4MappedAny(), V4Any()},
-        TestParam{V4MappedAny(), V4Loopback()},
-        TestParam{V4MappedAny(), V4MappedAny()},
-        TestParam{V4MappedAny(), V4MappedLoopback()},
-        TestParam{V4MappedLoopback(), V4Any()},
-        TestParam{V4MappedLoopback(), V4Loopback()},
-        TestParam{V4MappedLoopback(), V4MappedLoopback()},
-
-        // Listeners bound to IN6ADDR_ANY accept all connections.
-        TestParam{V6Any(), V4Any()}, TestParam{V6Any(), V4Loopback()},
-        TestParam{V6Any(), V4MappedAny()},
-        TestParam{V6Any(), V4MappedLoopback()}, TestParam{V6Any(), V6Any()},
-        TestParam{V6Any(), V6Loopback()},
-
-        // Listeners bound to IN6ADDR_LOOPBACK refuse connections using IPv4
-        // addresses.
-        TestParam{V6Loopback(), V6Any()},
-        TestParam{V6Loopback(), V6Loopback()}),
-    DescribeTestParam);
-
-struct ProtocolTestParam {
-  std::string description;
-  int type;
-};
-
-std::string DescribeProtocolTestParam(
-    ::testing::TestParamInfo<ProtocolTestParam> const& info) {
-  return info.param.description;
-}
+INSTANTIATE_TEST_SUITE_P(All, SocketInetLoopbackTest,
+                         SocketInetLoopbackTestValues(),
+                         DescribeSocketInetTestParam);
 
 using SocketMultiProtocolInetLoopbackTest =
     ::testing::TestWithParam<ProtocolTestParam>;
 
 TEST_P(SocketMultiProtocolInetLoopbackTest, BindAvoidsListeningPortsReuseAddr) {
-  const auto& param = GetParam();
+  ProtocolTestParam const& param = GetParam();
   // UDP sockets are allowed to bind/listen on the port w/ SO_REUSEADDR, for TCP
   // this is only permitted if there is no other listening socket.
   SKIP_IF(param.type != SOCK_STREAM);
@@ -222,11 +147,8 @@ TEST_P(SocketMultiProtocolInetLoopbackTest, BindAvoidsListeningPortsReuseAddr) {
   }
 }
 
-INSTANTIATE_TEST_SUITE_P(
-    AllFamilies, SocketMultiProtocolInetLoopbackTest,
-    ::testing::Values(ProtocolTestParam{"TCP", SOCK_STREAM},
-                      ProtocolTestParam{"UDP", SOCK_DGRAM}),
-    DescribeProtocolTestParam);
+INSTANTIATE_TEST_SUITE_P(AllFamilies, SocketMultiProtocolInetLoopbackTest,
+                         ProtocolTestValues(), DescribeProtocolTestParam);
 
 }  // namespace
 
diff --git a/test/syscalls/linux/socket_inet_loopback_test_params.h b/test/syscalls/linux/socket_inet_loopback_test_params.h
new file mode 100644
index 000000000..42b48eb8a
--- /dev/null
+++ b/test/syscalls/linux/socket_inet_loopback_test_params.h
@@ -0,0 +1,86 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GVISOR_TEST_SYSCALLS_LINUX_SOCKET_INET_LOOPBACK_TEST_PARAMS_H_
+#define GVISOR_TEST_SYSCALLS_LINUX_SOCKET_INET_LOOPBACK_TEST_PARAMS_H_
+
+#include "gtest/gtest.h"
+#include "test/syscalls/linux/socket_test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+struct SocketInetTestParam {
+  TestAddress listener;
+  TestAddress connector;
+};
+
+inline std::string DescribeSocketInetTestParam(
+    ::testing::TestParamInfo<SocketInetTestParam> const& info) {
+  return absl::StrCat("Listen", info.param.listener.description, "_Connect",
+                      info.param.connector.description);
+}
+
+inline auto SocketInetLoopbackTestValues() {
+  return ::testing::Values(
+      // Listeners bound to IPv4 addresses refuse connections using IPv6
+      // addresses.
+      SocketInetTestParam{V4Any(), V4Any()},
+      SocketInetTestParam{V4Any(), V4Loopback()},
+      SocketInetTestParam{V4Any(), V4MappedAny()},
+      SocketInetTestParam{V4Any(), V4MappedLoopback()},
+      SocketInetTestParam{V4Loopback(), V4Any()},
+      SocketInetTestParam{V4Loopback(), V4Loopback()},
+      SocketInetTestParam{V4Loopback(), V4MappedLoopback()},
+      SocketInetTestParam{V4MappedAny(), V4Any()},
+      SocketInetTestParam{V4MappedAny(), V4Loopback()},
+      SocketInetTestParam{V4MappedAny(), V4MappedAny()},
+      SocketInetTestParam{V4MappedAny(), V4MappedLoopback()},
+      SocketInetTestParam{V4MappedLoopback(), V4Any()},
+      SocketInetTestParam{V4MappedLoopback(), V4Loopback()},
+      SocketInetTestParam{V4MappedLoopback(), V4MappedLoopback()},
+
+      // Listeners bound to IN6ADDR_ANY accept all connections.
+      SocketInetTestParam{V6Any(), V4Any()},
+      SocketInetTestParam{V6Any(), V4Loopback()},
+      SocketInetTestParam{V6Any(), V4MappedAny()},
+      SocketInetTestParam{V6Any(), V4MappedLoopback()},
+      SocketInetTestParam{V6Any(), V6Any()},
+      SocketInetTestParam{V6Any(), V6Loopback()},
+
+      // Listeners bound to IN6ADDR_LOOPBACK refuse connections using IPv4
+      // addresses.
+      SocketInetTestParam{V6Loopback(), V6Any()},
+      SocketInetTestParam{V6Loopback(), V6Loopback()});
+}
+
+struct ProtocolTestParam {
+  std::string description;
+  int type;
+};
+
+inline std::string DescribeProtocolTestParam(
+    ::testing::TestParamInfo<ProtocolTestParam> const& info) {
+  return info.param.description;
+}
+
+inline auto ProtocolTestValues() {
+  return ::testing::Values(ProtocolTestParam{"TCP", SOCK_STREAM},
+                           ProtocolTestParam{"UDP", SOCK_DGRAM});
+}
+
+}  // namespace testing
+}  // namespace gvisor
+
+#endif  // GVISOR_TEST_SYSCALLS_LINUX_SOCKET_INET_LOOPBACK_TEST_PARAMS_H_
diff --git a/test/syscalls/linux/socket_test_util.cc b/test/syscalls/linux/socket_test_util.cc
index 83c33ec8d..5e36472b4 100644
--- a/test/syscalls/linux/socket_test_util.cc
+++ b/test/syscalls/linux/socket_test_util.cc
@@ -948,5 +948,124 @@ uint16_t ICMPChecksum(struct icmphdr icmphdr, const char* payload,
   return csum;
 }
 
+PosixErrorOr<uint16_t> AddrPort(int family, sockaddr_storage const& addr) {
+  switch (family) {
+    case AF_INET:
+      return static_cast<uint16_t>(
+          reinterpret_cast<sockaddr_in const*>(&addr)->sin_port);
+    case AF_INET6:
+      return static_cast<uint16_t>(
+          reinterpret_cast<sockaddr_in6 const*>(&addr)->sin6_port);
+    default:
+      return PosixError(EINVAL,
+                        absl::StrCat("unknown socket family: ", family));
+  }
+}
+
+PosixError SetAddrPort(int family, sockaddr_storage* addr, uint16_t port) {
+  switch (family) {
+    case AF_INET:
+      reinterpret_cast<sockaddr_in*>(addr)->sin_port = port;
+      return NoError();
+    case AF_INET6:
+      reinterpret_cast<sockaddr_in6*>(addr)->sin6_port = port;
+      return NoError();
+    default:
+      return PosixError(EINVAL,
+                        absl::StrCat("unknown socket family: ", family));
+  }
+}
+
+void SetupTimeWaitClose(const TestAddress* listener,
+                        const TestAddress* connector, bool reuse,
+                        bool accept_close, sockaddr_storage* listen_addr,
+                        sockaddr_storage* conn_bound_addr) {
+  // Create the listening socket.
+  FileDescriptor listen_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(listener->family(), SOCK_STREAM, IPPROTO_TCP));
+  if (reuse) {
+    ASSERT_THAT(setsockopt(listen_fd.get(), SOL_SOCKET, SO_REUSEADDR,
+                           &kSockOptOn, sizeof(kSockOptOn)),
+                SyscallSucceeds());
+  }
+  ASSERT_THAT(
+      bind(listen_fd.get(), AsSockAddr(listen_addr), listener->addr_len),
+      SyscallSucceeds());
+  ASSERT_THAT(listen(listen_fd.get(), SOMAXCONN), SyscallSucceeds());
+
+  // Get the port bound by the listening socket.
+  socklen_t addrlen = listener->addr_len;
+  ASSERT_THAT(getsockname(listen_fd.get(), AsSockAddr(listen_addr), &addrlen),
+              SyscallSucceeds());
+
+  uint16_t const port =
+      ASSERT_NO_ERRNO_AND_VALUE(AddrPort(listener->family(), *listen_addr));
+
+  // Connect to the listening socket.
+  FileDescriptor conn_fd = ASSERT_NO_ERRNO_AND_VALUE(
+      Socket(connector->family(), SOCK_STREAM, IPPROTO_TCP));
+
+  // We disable saves after this point as a S/R causes the netstack seed
+  // to be regenerated which changes what ports/ISN is picked for a given
+  // tuple (src ip,src port, dst ip, dst port). This can cause the final
+  // SYN to use a sequence number that looks like one from the current
+  // connection in TIME_WAIT and will not be accepted causing the test
+  // to timeout.
+  //
+  // TODO(gvisor.dev/issue/940): S/R portSeed/portHint
+  DisableSave ds;
+
+  sockaddr_storage conn_addr = connector->addr;
+  ASSERT_NO_ERRNO(SetAddrPort(connector->family(), &conn_addr, port));
+  ASSERT_THAT(RetryEINTR(connect)(conn_fd.get(), AsSockAddr(&conn_addr),
+                                  connector->addr_len),
+              SyscallSucceeds());
+
+  // Accept the connection.
+  auto accepted =
+      ASSERT_NO_ERRNO_AND_VALUE(Accept(listen_fd.get(), nullptr, nullptr));
+
+  // Get the address/port bound by the connecting socket.
+  socklen_t conn_addrlen = connector->addr_len;
+  ASSERT_THAT(
+      getsockname(conn_fd.get(), AsSockAddr(conn_bound_addr), &conn_addrlen),
+      SyscallSucceeds());
+
+  FileDescriptor active_closefd, passive_closefd;
+  if (accept_close) {
+    active_closefd = std::move(accepted);
+    passive_closefd = std::move(conn_fd);
+  } else {
+    active_closefd = std::move(conn_fd);
+    passive_closefd = std::move(accepted);
+  }
+
+  // shutdown to trigger TIME_WAIT.
+  ASSERT_THAT(shutdown(active_closefd.get(), SHUT_WR), SyscallSucceeds());
+  {
+    constexpr int kTimeout = 10000;
+    pollfd pfd = {
+        .fd = passive_closefd.get(),
+        .events = POLLIN,
+    };
+    ASSERT_THAT(poll(&pfd, 1, kTimeout), SyscallSucceedsWithValue(1));
+    ASSERT_EQ(pfd.revents, POLLIN);
+  }
+  ASSERT_THAT(shutdown(passive_closefd.get(), SHUT_WR), SyscallSucceeds());
+  {
+    constexpr int kTimeout = 10000;
+    constexpr int16_t want_events = POLLHUP;
+    pollfd pfd = {
+        .fd = active_closefd.get(),
+        .events = want_events,
+    };
+    ASSERT_THAT(poll(&pfd, 1, kTimeout), SyscallSucceedsWithValue(1));
+  }
+
+  // This sleep is needed to reduce flake to ensure that the passive-close
+  // ensures the state transitions to CLOSE from LAST_ACK.
+  absl::SleepFor(absl::Seconds(1));
+}
+
 }  // namespace testing
 }  // namespace gvisor
diff --git a/test/syscalls/linux/socket_test_util.h b/test/syscalls/linux/socket_test_util.h
index 76dc090e0..df4c26f26 100644
--- a/test/syscalls/linux/socket_test_util.h
+++ b/test/syscalls/linux/socket_test_util.h
@@ -564,6 +564,18 @@ inline sockaddr* AsSockAddr(sockaddr_un* s) {
   return reinterpret_cast<sockaddr*>(s);
 }
 
+PosixErrorOr<uint16_t> AddrPort(int family, sockaddr_storage const& addr);
+
+PosixError SetAddrPort(int family, sockaddr_storage* addr, uint16_t port);
+
+// setupTimeWaitClose sets up a socket endpoint in TIME_WAIT state.
+// Callers can choose to perform active close on either ends of the connection
+// and also specify if they want to enabled SO_REUSEADDR.
+void SetupTimeWaitClose(const TestAddress* listener,
+                        const TestAddress* connector, bool reuse,
+                        bool accept_close, sockaddr_storage* listen_addr,
+                        sockaddr_storage* conn_bound_addr);
+
 namespace internal {
 PosixErrorOr<int> TryPortAvailable(int port, AddressFamily family,
                                    SocketType type, bool reuse_addr);