diff --git a/libnm-util/nm-setting.c b/libnm-util/nm-setting.c
index 53e8f3438..3bcefbc57 100644
--- a/libnm-util/nm-setting.c
+++ b/libnm-util/nm-setting.c
@@ -402,7 +402,7 @@ nm_setting_new_from_hash (GType setting_type, GHashTable *hash)
 			continue;
 		}
 
-		nm_g_object_set_property ((GObject *) setting, prop_name, src_value, NULL);
+		(void) nm_g_object_set_property ((GObject *) setting, prop_name, src_value, NULL);
 	}
 
 	g_type_class_unref (class);
diff --git a/src/devices/bluetooth/nm-bluez5-manager.c b/src/devices/bluetooth/nm-bluez5-manager.c
index 1649da248..8c93f2a50 100644
--- a/src/devices/bluetooth/nm-bluez5-manager.c
+++ b/src/devices/bluetooth/nm-bluez5-manager.c
@@ -380,12 +380,12 @@ object_manager_interfaces_added (GDBusProxy      *proxy,
 	if (g_variant_lookup (dict, NM_BLUEZ5_DEVICE_INTERFACE, "a{sv}", NULL))
 		device_added (proxy, path, self);
 	if (g_variant_lookup (dict, NM_BLUEZ5_NETWORK_SERVER_INTERFACE, "a{sv}", NULL)) {
-		GVariant *adapter = g_variant_lookup_value (dict, NM_BLUEZ5_ADAPTER_INTERFACE, G_VARIANT_TYPE_DICTIONARY);
+		gs_unref_variant GVariant *adapter = g_variant_lookup_value (dict, NM_BLUEZ5_ADAPTER_INTERFACE, G_VARIANT_TYPE_DICTIONARY);
 		const char *address;
 
-		g_variant_lookup (adapter, "Address", "&s", &address);
-		network_server_added (proxy, path, address, self);
-		g_variant_unref (adapter);
+		if (   adapter
+		    && g_variant_lookup (adapter, "Address", "&s", &address))
+			network_server_added (proxy, path, address, self);
 	}
 }
 
diff --git a/src/devices/wwan/nm-modem-broadband.c b/src/devices/wwan/nm-modem-broadband.c
index 3a289f533..6e5f10a06 100644
--- a/src/devices/wwan/nm-modem-broadband.c
+++ b/src/devices/wwan/nm-modem-broadband.c
@@ -894,7 +894,15 @@ static_stage3_ip4_done (NMModemBroadband *self)
 
 	/* Missing gateway not a hard failure */
 	gw_string = mm_bearer_ip_config_get_gateway (self->_priv.ipv4_config);
-	nm_utils_parse_inaddr_bin (AF_INET, gw_string, &gw);
+	if (   !gw_string
+	    || !nm_utils_parse_inaddr_bin (AF_INET, gw_string, &gw)) {
+		error = g_error_new (NM_DEVICE_ERROR,
+		                     NM_DEVICE_ERROR_INVALID_CONNECTION,
+		                     "(%s) retrieving IP4 configuration failed: invalid gateway address %s%s%s",
+		                     nm_modem_get_uid (NM_MODEM (self)),
+		                     NM_PRINT_FMT_QUOTE_STRING (gw_string));
+		goto out;
+	}
 
 	data_port = mm_bearer_get_interface (self->_priv.bearer);
 	g_assert (data_port);
diff --git a/src/nm-core-utils.c b/src/nm-core-utils.c
index 4239c8982..6c72b8daf 100644
--- a/src/nm-core-utils.c
+++ b/src/nm-core-utils.c
@@ -2832,7 +2832,7 @@ nm_utils_fd_get_contents (int fd,
 		gsize n_have, n_alloc;
 		int fd2;
 
-		if (close_fd)
+		if (fd_keeper >= 0)
 			fd2 = nm_steal_fd (&fd_keeper);
 		else {
 			fd2 = dup (fd);
diff --git a/src/platform/nm-linux-platform.c b/src/platform/nm-linux-platform.c
index 79a0eb0b6..c4c93ed3f 100644
--- a/src/platform/nm-linux-platform.c
+++ b/src/platform/nm-linux-platform.c
@@ -3939,13 +3939,14 @@ do_request_link_no_delayed_actions (NMPlatform *platform, int ifindex, const cha
 {
 	NMLinuxPlatformPrivate *priv = NM_LINUX_PLATFORM_GET_PRIVATE (platform);
 	nm_auto_nlmsg struct nl_msg *nlmsg = NULL;
+	int nle;
 
 	if (name && !name[0])
 		name = NULL;
 
 	g_return_if_fail (ifindex > 0 || name);
 
-	_LOGD ("do-request-link: %d %s", ifindex, name ? name : "");
+	_LOGD ("do-request-link: %d %s", ifindex, name ?: "");
 
 	if (ifindex > 0) {
 		const NMDedupMultiEntry *entry;
@@ -3965,8 +3966,15 @@ do_request_link_no_delayed_actions (NMPlatform *platform, int ifindex, const cha
 	                          name,
 	                          0,
 	                          0);
-	if (nlmsg)
-		_nl_send_nlmsg (platform, nlmsg, NULL, DELAYED_ACTION_RESPONSE_TYPE_VOID, NULL);
+	if (nlmsg) {
+		nle = _nl_send_nlmsg (platform, nlmsg, NULL, DELAYED_ACTION_RESPONSE_TYPE_VOID, NULL);
+		if (nle < 0) {
+			_LOGE ("do-request-link: %d %s: failed sending netlink request \"%s\" (%d)",
+			       ifindex, name ?: "",
+			       nl_geterror (nle), -nle);
+			return;
+		}
+	}
 }
 
 static void
diff --git a/src/settings/plugins/keyfile/nms-keyfile-writer.c b/src/settings/plugins/keyfile/nms-keyfile-writer.c
index 1a68e5dc0..270a217e2 100644
--- a/src/settings/plugins/keyfile/nms-keyfile-writer.c
+++ b/src/settings/plugins/keyfile/nms-keyfile-writer.c
@@ -213,9 +213,8 @@ _internal_write_connection (NMConnection *connection,
 	if (!data)
 		return FALSE;
 
-
 	if (!g_file_test (keyfile_dir, G_FILE_TEST_IS_DIR))
-		g_mkdir_with_parents (keyfile_dir, 0755);
+		(void) g_mkdir_with_parents (keyfile_dir, 0755);
 
 	/* If we have existing file path, use it. Else generate one from
 	 * connection's ID.