Index: uspace/lib/usbvirt/src/ipc_dev.c
===================================================================
--- uspace/lib/usbvirt/src/ipc_dev.c	(revision fafb8e5dc8a80c87cf66270ca6f93d574a95471c)
+++ uspace/lib/usbvirt/src/ipc_dev.c	(revision ffed09d79c4f737ed0a49581161c8c053ce34980)
@@ -1,3 +1,4 @@
 /*
+ * Copyright (c) 2023 Jiri Svoboda
  * Copyright (c) 2011 Vojtech Horky
  * All rights reserved.
@@ -59,4 +60,5 @@
 	size_t accepted_size;
 	if (!async_data_read_receive(&call, &accepted_size)) {
+		async_answer_0(&call, EINVAL);
 		async_answer_0(icall, EINVAL);
 		return;
@@ -94,4 +96,5 @@
 	ipc_call_t data;
 	if (!async_data_read_receive(&data, &data_len)) {
+		async_answer_0(&data, EPARTY);
 		async_answer_0(icall, EPARTY);
 		free(setup_packet);
@@ -101,4 +104,5 @@
 	void *buffer = malloc(data_len);
 	if (buffer == NULL) {
+		async_answer_0(&data, EPARTY);
 		async_answer_0(icall, ENOMEM);
 		free(setup_packet);
@@ -184,4 +188,5 @@
 	ipc_call_t data;
 	if (!async_data_read_receive(&data, &data_len)) {
+		async_answer_0(&data, EPARTY);
 		async_answer_0(icall, EPARTY);
 		return;
@@ -190,4 +195,5 @@
 	void *buffer = malloc(data_len);
 	if (buffer == NULL) {
+		async_answer_0(&data, EPARTY);
 		async_answer_0(icall, ENOMEM);
 		return;