ws2_32: Cope with NULL address in connect() call.

dlls/ws2_32/socket.c

@@ -1731,14 +1731,17 @@ static inline BOOL supported_protocol(int protocol)
 
 /**********************************************************************/
 
-/* Returns the length of the converted address if successful, 0 if it was too small to
- * start with.
+/* Returns the length of the converted address if successful, 0 if it was too
+ * small to start with or unknown family or invalid address buffer.
  */
 static unsigned int ws_sockaddr_ws2u(const struct WS_sockaddr* wsaddr, int wsaddrlen,
                                      union generic_unix_sockaddr *uaddr)
 {
     unsigned int uaddrlen = 0;
 
+    if (!wsaddr)
+        return 0;
+
     switch (wsaddr->sa_family)
     {
 #ifdef HAS_IPX

dlls/ws2_32/tests/sock.c

@@ -5841,6 +5841,11 @@ static void test_events(int useMessages)
         goto end;
     }
 
+    SetLastError(0xdeadbeef);
+    ret = connect(src, NULL, 0);
+    ok(ret == SOCKET_ERROR, "expected -1, got %d\n", ret);
+    ok(GetLastError() == WSAEFAULT, "expected 10014, got %d\n", GetLastError());
+
     ret = connect(src, (struct sockaddr*)&addr, sizeof(addr));
     if (ret == SOCKET_ERROR && WSAGetLastError() != WSAEWOULDBLOCK)
     {