diff --git a/block/nbd.c b/block/nbd.c
index 3dec860..7403195 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -42,6 +42,9 @@
 
 typedef struct BDRVNBDState {
     NbdClientSession client;
+
+    /* For nbd_refresh_filename() */
+    char *path, *host, *port, *export, *tlscredsid;
 } BDRVNBDState;
 
 static int nbd_parse_uri(const char *filename, QDict *options)
@@ -188,13 +191,15 @@ out:
     g_free(file);
 }
 
-static SocketAddress *nbd_config(BDRVNBDState *s, QemuOpts *opts, char **export,
-                                 Error **errp)
+static SocketAddress *nbd_config(BDRVNBDState *s, QemuOpts *opts, Error **errp)
 {
     SocketAddress *saddr;
 
-    if (!qemu_opt_get(opts, "path") == !qemu_opt_get(opts, "host")) {
-        if (qemu_opt_get(opts, "path")) {
+    s->path = g_strdup(qemu_opt_get(opts, "path"));
+    s->host = g_strdup(qemu_opt_get(opts, "host"));
+
+    if (!s->path == !s->host) {
+        if (s->path) {
             error_setg(errp, "path and host may not be used at the same time.");
         } else {
             error_setg(errp, "one of path and host must be specified.");
@@ -204,17 +209,20 @@ static SocketAddress *nbd_config(BDRVNBDState *s, QemuOpts *opts, char **export,
 
     saddr = g_new0(SocketAddress, 1);
 
-    if (qemu_opt_get(opts, "path")) {
+    if (s->path) {
         UnixSocketAddress *q_unix;
         saddr->type = SOCKET_ADDRESS_KIND_UNIX;
         q_unix = saddr->u.q_unix.data = g_new0(UnixSocketAddress, 1);
-        q_unix->path = g_strdup(qemu_opt_get(opts, "path"));
+        q_unix->path = g_strdup(s->path);
     } else {
         InetSocketAddress *inet;
+
+        s->port = g_strdup(qemu_opt_get(opts, "port"));
+
         saddr->type = SOCKET_ADDRESS_KIND_INET;
         inet = saddr->u.inet.data = g_new0(InetSocketAddress, 1);
-        inet->host = g_strdup(qemu_opt_get(opts, "host"));
-        inet->port = g_strdup(qemu_opt_get(opts, "port"));
+        inet->host = g_strdup(s->host);
+        inet->port = g_strdup(s->port);
         if (!inet->port) {
             inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
         }
@@ -222,7 +230,7 @@ static SocketAddress *nbd_config(BDRVNBDState *s, QemuOpts *opts, char **export,
 
     s->client.is_unix = saddr->type == SOCKET_ADDRESS_KIND_UNIX;
 
-    *export = g_strdup(qemu_opt_get(opts, "export"));
+    s->export = g_strdup(qemu_opt_get(opts, "export"));
 
     return saddr;
 }
@@ -323,10 +331,8 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
     BDRVNBDState *s = bs->opaque;
     QemuOpts *opts = NULL;
     Error *local_err = NULL;
-    char *export = NULL;
     QIOChannelSocket *sioc = NULL;
     SocketAddress *saddr = NULL;
-    const char *tlscredsid;
     QCryptoTLSCreds *tlscreds = NULL;
     const char *hostname = NULL;
     int ret = -EINVAL;
@@ -339,14 +345,14 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
     }
 
     /* Pop the config into our state object. Exit if invalid. */
-    saddr = nbd_config(s, opts, &export, errp);
+    saddr = nbd_config(s, opts, errp);
     if (!saddr) {
         goto error;
     }
 
-    tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds"));
-    if (tlscredsid) {
-        tlscreds = nbd_get_tls_creds(tlscredsid, errp);
+    s->tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds"));
+    if (s->tlscredsid) {
+        tlscreds = nbd_get_tls_creds(s->tlscredsid, errp);
         if (!tlscreds) {
             goto error;
         }
@@ -368,7 +374,7 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
     }
 
     /* NBD handshake */
-    ret = nbd_client_init(bs, sioc, export,
+    ret = nbd_client_init(bs, sioc, s->export,
                           tlscreds, hostname, errp);
  error:
     if (sioc) {
@@ -377,8 +383,14 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
     if (tlscreds) {
         object_unref(OBJECT(tlscreds));
     }
+    if (ret < 0) {
+        g_free(s->path);
+        g_free(s->host);
+        g_free(s->port);
+        g_free(s->export);
+        g_free(s->tlscredsid);
+    }
     qapi_free_SocketAddress(saddr);
-    g_free(export);
     qemu_opts_del(opts);
     return ret;
 }
@@ -396,7 +408,15 @@ static void nbd_refresh_limits(BlockDriverState *bs, Error **errp)
 
 static void nbd_close(BlockDriverState *bs)
 {
+    BDRVNBDState *s = bs->opaque;
+
     nbd_client_close(bs);
+
+    g_free(s->path);
+    g_free(s->host);
+    g_free(s->port);
+    g_free(s->export);
+    g_free(s->tlscredsid);
 }
 
 static int64_t nbd_getlength(BlockDriverState *bs)
@@ -419,48 +439,45 @@ static void nbd_attach_aio_context(BlockDriverState *bs,
 
 static void nbd_refresh_filename(BlockDriverState *bs, QDict *options)
 {
+    BDRVNBDState *s = bs->opaque;
     QDict *opts = qdict_new();
-    const char *path   = qdict_get_try_str(options, "path");
-    const char *host   = qdict_get_try_str(options, "host");
-    const char *port   = qdict_get_try_str(options, "port");
-    const char *export = qdict_get_try_str(options, "export");
-    const char *tlscreds = qdict_get_try_str(options, "tls-creds");
 
     qdict_put_obj(opts, "driver", QOBJECT(qstring_from_str("nbd")));
 
-    if (path && export) {
+    if (s->path && s->export) {
         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
-                 "nbd+unix:///%s?socket=%s", export, path);
-    } else if (path && !export) {
+                 "nbd+unix:///%s?socket=%s", s->export, s->path);
+    } else if (s->path && !s->export) {
         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
-                 "nbd+unix://?socket=%s", path);
-    } else if (!path && export && port) {
+                 "nbd+unix://?socket=%s", s->path);
+    } else if (!s->path && s->export && s->port) {
         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
-                 "nbd://%s:%s/%s", host, port, export);
-    } else if (!path && export && !port) {
+                 "nbd://%s:%s/%s", s->host, s->port, s->export);
+    } else if (!s->path && s->export && !s->port) {
         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
-                 "nbd://%s/%s", host, export);
-    } else if (!path && !export && port) {
+                 "nbd://%s/%s", s->host, s->export);
+    } else if (!s->path && !s->export && s->port) {
         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
-                 "nbd://%s:%s", host, port);
-    } else if (!path && !export && !port) {
+                 "nbd://%s:%s", s->host, s->port);
+    } else if (!s->path && !s->export && !s->port) {
         snprintf(bs->exact_filename, sizeof(bs->exact_filename),
-                 "nbd://%s", host);
+                 "nbd://%s", s->host);
     }
 
-    if (path) {
-        qdict_put_obj(opts, "path", QOBJECT(qstring_from_str(path)));
-    } else if (port) {
-        qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(host)));
-        qdict_put_obj(opts, "port", QOBJECT(qstring_from_str(port)));
+    if (s->path) {
+        qdict_put_obj(opts, "path", QOBJECT(qstring_from_str(s->path)));
+    } else if (s->port) {
+        qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(s->host)));
+        qdict_put_obj(opts, "port", QOBJECT(qstring_from_str(s->port)));
     } else {
-        qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(host)));
+        qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(s->host)));
     }
-    if (export) {
-        qdict_put_obj(opts, "export", QOBJECT(qstring_from_str(export)));
+    if (s->export) {
+        qdict_put_obj(opts, "export", QOBJECT(qstring_from_str(s->export)));
     }
-    if (tlscreds) {
-        qdict_put_obj(opts, "tls-creds", QOBJECT(qstring_from_str(tlscreds)));
+    if (s->tlscredsid) {
+        qdict_put_obj(opts, "tls-creds",
+                      QOBJECT(qstring_from_str(s->tlscredsid)));
     }
 
     bs->full_open_options = opts;
