diff --git a/examples/client.cc b/examples/client.cc
index f4035b0f0..6221d66d8 100644
--- a/examples/client.cc
+++ b/examples/client.cc
@@ -1184,8 +1184,7 @@ int Client::change_local_addr() {
   if (config.nat_rebinding) {
     ngtcp2_addr addr;
     ngtcp2_conn_set_local_addr(
-        conn_,
-        ngtcp2_addr_init(&addr, &local_addr.su.sa, local_addr.len, nullptr));
+        conn_, ngtcp2_addr_init(&addr, &local_addr.su.sa, local_addr.len));
   } else {
     auto path = ngtcp2_path{{local_addr.len, &local_addr.su.sa},
                             {remote_addr.len, &remote_addr.su.sa}};
diff --git a/examples/h09client.cc b/examples/h09client.cc
index 9d2a01e1b..c3ba77139 100644
--- a/examples/h09client.cc
+++ b/examples/h09client.cc
@@ -1129,8 +1129,7 @@ int Client::change_local_addr() {
   if (config.nat_rebinding) {
     ngtcp2_addr addr;
     ngtcp2_conn_set_local_addr(
-        conn_,
-        ngtcp2_addr_init(&addr, &local_addr.su.sa, local_addr.len, nullptr));
+        conn_, ngtcp2_addr_init(&addr, &local_addr.su.sa, local_addr.len));
   } else {
     auto path = ngtcp2_path{{local_addr.len, &local_addr.su.sa},
                             {remote_addr.len, &remote_addr.su.sa}};
diff --git a/examples/h09server.cc b/examples/h09server.cc
index ae7992704..c457a05a3 100644
--- a/examples/h09server.cc
+++ b/examples/h09server.cc
@@ -854,9 +854,9 @@ int Handler::init(const Endpoint &ep, const Address &local_addr,
   }
 
   auto path =
-      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa),
-                   const_cast<Endpoint *>(&ep)},
-                  {salen, const_cast<sockaddr *>(sa)}};
+      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa)},
+                  {salen, const_cast<sockaddr *>(sa)},
+                  const_cast<Endpoint *>(&ep)};
   if (auto rv =
           ngtcp2_conn_server_new(&conn_, dcid, &scid_, &path, version,
                                  &callbacks, &settings, &params, nullptr, this);
@@ -890,9 +890,9 @@ int Handler::feed_data(const Endpoint &ep, const Address &local_addr,
                        const ngtcp2_pkt_info *pi, uint8_t *data,
                        size_t datalen) {
   auto path =
-      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa),
-                   const_cast<Endpoint *>(&ep)},
-                  {salen, const_cast<sockaddr *>(sa)}};
+      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa)},
+                  {salen, const_cast<sockaddr *>(sa)},
+                  const_cast<Endpoint *>(&ep)};
 
   if (auto rv = ngtcp2_conn_read_pkt(conn_, &path, pi, data, datalen,
                                      util::timestamp(loop_));
@@ -1044,10 +1044,10 @@ int Handler::write_streams() {
 
     if (nwrite == 0) {
       if (bufpos - buf.data()) {
-        server_->send_packet(
-            *static_cast<Endpoint *>(prev_path.path.local.user_data),
-            prev_path.path.local, prev_path.path.remote, prev_ecn, buf.data(),
-            bufpos - buf.data(), max_pktlen_);
+        server_->send_packet(*static_cast<Endpoint *>(prev_path.path.user_data),
+                             prev_path.path.local, prev_path.path.remote,
+                             prev_ecn, buf.data(), bufpos - buf.data(),
+                             max_pktlen_);
         reset_idle_timer();
       }
       // We are congestion limited.
@@ -1062,12 +1062,12 @@ int Handler::write_streams() {
       prev_ecn = pi.ecn;
     } else if (!ngtcp2_path_eq(&prev_path.path, &path.path) ||
                prev_ecn != pi.ecn) {
-      server_->send_packet(
-          *static_cast<Endpoint *>(prev_path.path.local.user_data),
-          prev_path.path.local, prev_path.path.remote, prev_ecn, buf.data(),
-          bufpos - buf.data() - nwrite, max_pktlen_);
+      server_->send_packet(*static_cast<Endpoint *>(prev_path.path.user_data),
+                           prev_path.path.local, prev_path.path.remote,
+                           prev_ecn, buf.data(), bufpos - buf.data() - nwrite,
+                           max_pktlen_);
 
-      server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+      server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                            path.path.local, path.path.remote, pi.ecn,
                            bufpos - nwrite, nwrite, max_pktlen_);
       reset_idle_timer();
@@ -1076,7 +1076,7 @@ int Handler::write_streams() {
     }
 
     if (++pktcnt == max_pktcnt || static_cast<size_t>(nwrite) < max_pktlen_) {
-      server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+      server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                            path.path.local, path.path.remote, pi.ecn,
                            buf.data(), bufpos - buf.data(), max_pktlen_);
       reset_idle_timer();
@@ -1086,7 +1086,7 @@ int Handler::write_streams() {
 #else  // !NGTCP2_ENABLE_UDP_GSO
     reset_idle_timer();
 
-    server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+    server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                          path.path.local, path.path.remote, pi.ecn, buf.data(),
                          bufpos - buf.data(), 0);
     if (++pktcnt == max_pktcnt) {
@@ -1185,10 +1185,9 @@ int Handler::send_conn_close() {
 
   auto path = ngtcp2_conn_get_path(conn_);
 
-  return server_->send_packet(*static_cast<Endpoint *>(path->local.user_data),
-                              path->local, path->remote, /* ecn = */ 0,
-                              conn_closebuf_->rpos(), conn_closebuf_->size(),
-                              0);
+  return server_->send_packet(
+      *static_cast<Endpoint *>(path->user_data), path->local, path->remote,
+      /* ecn = */ 0, conn_closebuf_->rpos(), conn_closebuf_->size(), 0);
 }
 
 void Handler::schedule_retransmit() {
diff --git a/examples/perfserver.cc b/examples/perfserver.cc
index 161288756..9de3e2e4f 100644
--- a/examples/perfserver.cc
+++ b/examples/perfserver.cc
@@ -590,9 +590,9 @@ int Handler::init(const Endpoint &ep, const Address &local_addr,
   }
 
   auto path =
-      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa),
-                   const_cast<Endpoint *>(&ep)},
-                  {salen, const_cast<sockaddr *>(sa)}};
+      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa)},
+                  {salen, const_cast<sockaddr *>(sa)},
+                  const_cast<Endpoint *>(&ep)};
   if (auto rv =
           ngtcp2_conn_server_new(&conn_, dcid, &scid_, &path, version,
                                  &callbacks, &settings, &params, nullptr, this);
@@ -626,9 +626,9 @@ int Handler::feed_data(const Endpoint &ep, const Address &local_addr,
                        const ngtcp2_pkt_info *pi, uint8_t *data,
                        size_t datalen) {
   auto path =
-      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa),
-                   const_cast<Endpoint *>(&ep)},
-                  {salen, const_cast<sockaddr *>(sa)}};
+      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa)},
+                  {salen, const_cast<sockaddr *>(sa)},
+                  const_cast<Endpoint *>(&ep)};
 
   if (auto rv = ngtcp2_conn_read_pkt(conn_, &path, pi, data, datalen,
                                      util::timestamp(loop_));
@@ -789,10 +789,10 @@ int Handler::write_streams() {
 
     if (nwrite == 0) {
       if (bufpos - buf.data()) {
-        server_->send_packet(
-            *static_cast<Endpoint *>(prev_path.path.local.user_data),
-            prev_path.path.local, prev_path.path.remote, prev_ecn, buf.data(),
-            bufpos - buf.data(), max_pktlen_);
+        server_->send_packet(*static_cast<Endpoint *>(prev_path.path.user_data),
+                             prev_path.path.local, prev_path.path.remote,
+                             prev_ecn, buf.data(), bufpos - buf.data(),
+                             max_pktlen_);
         reset_idle_timer();
       }
       // We are congestion limited.
@@ -807,12 +807,12 @@ int Handler::write_streams() {
       prev_ecn = pi.ecn;
     } else if (!ngtcp2_path_eq(&prev_path.path, &path.path) ||
                prev_ecn != pi.ecn) {
-      server_->send_packet(
-          *static_cast<Endpoint *>(prev_path.path.local.user_data),
-          prev_path.path.local, prev_path.path.remote, prev_ecn, buf.data(),
-          bufpos - buf.data() - nwrite, max_pktlen_);
+      server_->send_packet(*static_cast<Endpoint *>(prev_path.path.user_data),
+                           prev_path.path.local, prev_path.path.remote,
+                           prev_ecn, buf.data(), bufpos - buf.data() - nwrite,
+                           max_pktlen_);
 
-      server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+      server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                            path.path.local, path.path.remote, pi.ecn,
                            bufpos - nwrite, nwrite, max_pktlen_);
       reset_idle_timer();
@@ -821,7 +821,7 @@ int Handler::write_streams() {
     }
 
     if (++pktcnt == max_pktcnt || static_cast<size_t>(nwrite) < max_pktlen_) {
-      server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+      server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                            path.path.local, path.path.remote, pi.ecn,
                            buf.data(), bufpos - buf.data(), max_pktlen_);
       reset_idle_timer();
@@ -831,7 +831,7 @@ int Handler::write_streams() {
 #else  // !NGTCP2_ENABLE_UDP_GSO
     reset_idle_timer();
 
-    server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+    server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                          path.path.local, path.path.remote, pi.ecn, buf.data(),
                          bufpos - buf.data(), 0);
     if (++pktcnt == max_pktcnt) {
@@ -930,10 +930,9 @@ int Handler::send_conn_close() {
 
   auto path = ngtcp2_conn_get_path(conn_);
 
-  return server_->send_packet(*static_cast<Endpoint *>(path->local.user_data),
-                              path->local, path->remote,
-                              /* ecn = */ 0, conn_closebuf_->rpos(),
-                              conn_closebuf_->size(), 0);
+  return server_->send_packet(
+      *static_cast<Endpoint *>(path->user_data), path->local, path->remote,
+      /* ecn = */ 0, conn_closebuf_->rpos(), conn_closebuf_->size(), 0);
 }
 
 void Handler::schedule_retransmit() {
diff --git a/examples/server.cc b/examples/server.cc
index 5bdafa15e..c9bb9ed3a 100644
--- a/examples/server.cc
+++ b/examples/server.cc
@@ -1575,9 +1575,9 @@ int Handler::init(const Endpoint &ep, const Address &local_addr,
   }
 
   auto path =
-      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa),
-                   const_cast<Endpoint *>(&ep)},
-                  {salen, const_cast<sockaddr *>(sa)}};
+      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa)},
+                  {salen, const_cast<sockaddr *>(sa)},
+                  const_cast<Endpoint *>(&ep)};
   if (auto rv =
           ngtcp2_conn_server_new(&conn_, dcid, &scid_, &path, version,
                                  &callbacks, &settings, &params, nullptr, this);
@@ -1611,9 +1611,9 @@ int Handler::feed_data(const Endpoint &ep, const Address &local_addr,
                        const ngtcp2_pkt_info *pi, uint8_t *data,
                        size_t datalen) {
   auto path =
-      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa),
-                   const_cast<Endpoint *>(&ep)},
-                  {salen, const_cast<sockaddr *>(sa)}};
+      ngtcp2_path{{local_addr.len, const_cast<sockaddr *>(&local_addr.su.sa)},
+                  {salen, const_cast<sockaddr *>(sa)},
+                  const_cast<Endpoint *>(&ep)};
 
   if (auto rv = ngtcp2_conn_read_pkt(conn_, &path, pi, data, datalen,
                                      util::timestamp(loop_));
@@ -1796,10 +1796,10 @@ int Handler::write_streams() {
 
     if (nwrite == 0) {
       if (bufpos - buf.data()) {
-        server_->send_packet(
-            *static_cast<Endpoint *>(prev_path.path.local.user_data),
-            prev_path.path.local, prev_path.path.remote, prev_ecn, buf.data(),
-            bufpos - buf.data(), max_pktlen_);
+        server_->send_packet(*static_cast<Endpoint *>(prev_path.path.user_data),
+                             prev_path.path.local, prev_path.path.remote,
+                             prev_ecn, buf.data(), bufpos - buf.data(),
+                             max_pktlen_);
         reset_idle_timer();
       }
       // We are congestion limited.
@@ -1814,12 +1814,12 @@ int Handler::write_streams() {
       prev_ecn = pi.ecn;
     } else if (!ngtcp2_path_eq(&prev_path.path, &path.path) ||
                prev_ecn != pi.ecn) {
-      server_->send_packet(
-          *static_cast<Endpoint *>(prev_path.path.local.user_data),
-          prev_path.path.local, prev_path.path.remote, prev_ecn, buf.data(),
-          bufpos - buf.data() - nwrite, max_pktlen_);
+      server_->send_packet(*static_cast<Endpoint *>(prev_path.path.user_data),
+                           prev_path.path.local, prev_path.path.remote,
+                           prev_ecn, buf.data(), bufpos - buf.data() - nwrite,
+                           max_pktlen_);
 
-      server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+      server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                            path.path.local, path.path.remote, pi.ecn,
                            bufpos - nwrite, nwrite, max_pktlen_);
 
@@ -1829,7 +1829,7 @@ int Handler::write_streams() {
     }
 
     if (++pktcnt == max_pktcnt || static_cast<size_t>(nwrite) < max_pktlen_) {
-      server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+      server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                            path.path.local, path.path.remote, pi.ecn,
                            buf.data(), bufpos - buf.data(), max_pktlen_);
       reset_idle_timer();
@@ -1839,7 +1839,7 @@ int Handler::write_streams() {
 #else  // !NGTCP2_ENABLE_UDP_GSO
     reset_idle_timer();
 
-    server_->send_packet(*static_cast<Endpoint *>(path.path.local.user_data),
+    server_->send_packet(*static_cast<Endpoint *>(path.path.user_data),
                          path.path.local, path.path.remote, pi.ecn, buf.data(),
                          bufpos - buf.data(), 0);
     if (++pktcnt == max_pktcnt) {
@@ -1938,10 +1938,9 @@ int Handler::send_conn_close() {
 
   auto path = ngtcp2_conn_get_path(conn_);
 
-  return server_->send_packet(*static_cast<Endpoint *>(path->local.user_data),
-                              path->local, path->remote,
-                              /* ecn = */ 0, conn_closebuf_->rpos(),
-                              conn_closebuf_->size(), 0);
+  return server_->send_packet(
+      *static_cast<Endpoint *>(path->user_data), path->local, path->remote,
+      /* ecn = */ 0, conn_closebuf_->rpos(), conn_closebuf_->size(), 0);
 }
 
 void Handler::schedule_retransmit() {
diff --git a/lib/includes/ngtcp2/ngtcp2.h b/lib/includes/ngtcp2/ngtcp2.h
index 2e0555187..d97cb0ca4 100644
--- a/lib/includes/ngtcp2/ngtcp2.h
+++ b/lib/includes/ngtcp2/ngtcp2.h
@@ -1864,11 +1864,6 @@ typedef struct ngtcp2_addr {
    * address.  It must not be ``NULL``.
    */
   struct sockaddr *addr;
-  /**
-   * :member:`user_data` is an arbitrary data and opaque to the
-   * library.
-   */
-  void *user_data;
 } ngtcp2_addr;
 
 /**
@@ -1886,6 +1881,11 @@ typedef struct ngtcp2_path {
    * :member:`remote` is the address of remote endpoint.
    */
   ngtcp2_addr remote;
+  /**
+   * :member:`user_data` is an arbitrary data and opaque to the
+   * library.
+   */
+  void *user_data;
 } ngtcp2_path;
 
 /**
@@ -4626,7 +4626,7 @@ NGTCP2_EXTERN uint64_t ngtcp2_err_infer_quic_transport_error_code(int liberr);
  */
 NGTCP2_EXTERN ngtcp2_addr *ngtcp2_addr_init(ngtcp2_addr *dest,
                                             const struct sockaddr *addr,
-                                            size_t addrlen, void *user_data);
+                                            size_t addrlen);
 
 /**
  * @function
@@ -4637,10 +4637,9 @@ NGTCP2_EXTERN ngtcp2_addr *ngtcp2_addr_init(ngtcp2_addr *dest,
 NGTCP2_EXTERN void ngtcp2_path_storage_init(ngtcp2_path_storage *ps,
                                             const struct sockaddr *local_addr,
                                             size_t local_addrlen,
-                                            void *local_user_data,
                                             const struct sockaddr *remote_addr,
                                             size_t remote_addrlen,
-                                            void *remote_user_data);
+                                            void *user_data);
 
 /**
  * @function
diff --git a/lib/ngtcp2_addr.c b/lib/ngtcp2_addr.c
index 22af219a9..27197a694 100644
--- a/lib/ngtcp2_addr.c
+++ b/lib/ngtcp2_addr.c
@@ -40,10 +40,9 @@
 #endif
 
 ngtcp2_addr *ngtcp2_addr_init(ngtcp2_addr *dest, const struct sockaddr *addr,
-                              size_t addrlen, void *user_data) {
+                              size_t addrlen) {
   dest->addrlen = addrlen;
   dest->addr = (struct sockaddr *)addr;
-  dest->user_data = user_data;
   return dest;
 }
 
@@ -52,7 +51,6 @@ void ngtcp2_addr_copy(ngtcp2_addr *dest, const ngtcp2_addr *src) {
   if (src->addrlen) {
     memcpy(dest->addr, src->addr, src->addrlen);
   }
-  dest->user_data = src->user_data;
 }
 
 void ngtcp2_addr_copy_byte(ngtcp2_addr *dest, const struct sockaddr *addr,
diff --git a/lib/ngtcp2_conn.c b/lib/ngtcp2_conn.c
index 38fef38e0..54ee5f2c5 100644
--- a/lib/ngtcp2_conn.c
+++ b/lib/ngtcp2_conn.c
@@ -7049,7 +7049,7 @@ static int conn_select_preferred_addr(ngtcp2_conn *conn) {
   ngtcp2_pv *pv;
   ngtcp2_dcid *dcid;
 
-  ngtcp2_addr_init(&addr, (struct sockaddr *)&buf, 0, NULL);
+  ngtcp2_addr_init(&addr, (struct sockaddr *)&buf, 0);
 
   if (ngtcp2_ringbuf_len(&conn->dcid.unused) == 0) {
     return 0;
diff --git a/lib/ngtcp2_path.c b/lib/ngtcp2_path.c
index 3f35f28ef..7a51e4da5 100644
--- a/lib/ngtcp2_path.c
+++ b/lib/ngtcp2_path.c
@@ -37,6 +37,7 @@ void ngtcp2_path_init(ngtcp2_path *path, const ngtcp2_addr *local,
 void ngtcp2_path_copy(ngtcp2_path *dest, const ngtcp2_path *src) {
   ngtcp2_addr_copy(&dest->local, &src->local);
   ngtcp2_addr_copy(&dest->remote, &src->remote);
+  dest->user_data = src->user_data;
 }
 
 int ngtcp2_path_eq(const ngtcp2_path *a, const ngtcp2_path *b) {
@@ -46,29 +47,31 @@ int ngtcp2_path_eq(const ngtcp2_path *a, const ngtcp2_path *b) {
 
 void ngtcp2_path_storage_init(ngtcp2_path_storage *ps,
                               const struct sockaddr *local_addr,
-                              size_t local_addrlen, void *local_user_data,
+                              size_t local_addrlen,
                               const struct sockaddr *remote_addr,
-                              size_t remote_addrlen, void *remote_user_data) {
+                              size_t remote_addrlen, void *user_data) {
   ngtcp2_addr_init(&ps->path.local, (const struct sockaddr *)&ps->local_addrbuf,
-                   0, local_user_data);
+                   0);
   ngtcp2_addr_init(&ps->path.remote,
-                   (const struct sockaddr *)&ps->remote_addrbuf, 0,
-                   remote_user_data);
+                   (const struct sockaddr *)&ps->remote_addrbuf, 0);
 
   ngtcp2_addr_copy_byte(&ps->path.local, local_addr, local_addrlen);
   ngtcp2_addr_copy_byte(&ps->path.remote, remote_addr, remote_addrlen);
+
+  ps->path.user_data = user_data;
 }
 
 void ngtcp2_path_storage_init2(ngtcp2_path_storage *ps,
                                const ngtcp2_path *path) {
   ngtcp2_path_storage_init(ps, path->local.addr, path->local.addrlen,
-                           path->local.user_data, path->remote.addr,
-                           path->remote.addrlen, path->remote.user_data);
+                           path->remote.addr, path->remote.addrlen,
+                           path->user_data);
 }
 
 void ngtcp2_path_storage_zero(ngtcp2_path_storage *ps) {
   ngtcp2_addr_init(&ps->path.local, (const struct sockaddr *)&ps->local_addrbuf,
-                   0, NULL);
+                   0);
   ngtcp2_addr_init(&ps->path.remote,
-                   (const struct sockaddr *)&ps->remote_addrbuf, 0, NULL);
+                   (const struct sockaddr *)&ps->remote_addrbuf, 0);
+  ps->path.user_data = NULL;
 }
diff --git a/tests/ngtcp2_test_helper.c b/tests/ngtcp2_test_helper.c
index 2fc5402a4..3d67ae138 100644
--- a/tests/ngtcp2_test_helper.c
+++ b/tests/ngtcp2_test_helper.c
@@ -496,6 +496,6 @@ void path_init(ngtcp2_path_storage *path, uint32_t local_addr,
   addr_init(&la, local_addr, local_port);
   addr_init(&ra, remote_addr, remote_port);
 
-  ngtcp2_path_storage_init(path, (struct sockaddr *)&la, sizeof(la), NULL,
+  ngtcp2_path_storage_init(path, (struct sockaddr *)&la, sizeof(la),
                            (struct sockaddr *)&ra, sizeof(ra), NULL);
 }