Index: uspace/lib/packet/generic/packet_server.c
===================================================================
--- uspace/lib/packet/generic/packet_server.c	(revision 515a00da5c882d507188dd5080d5a5df1015d9c3)
+++ uspace/lib/packet/generic/packet_server.c	(revision 57f737ade8b89da95396b6c659101b3ae96675d0)
@@ -321,6 +321,8 @@
 		return ENOMEM;
 
-	if (!async_share_in_receive(&callid, &size))
+	if (!async_share_in_receive(&callid, &size)) {
+		ipc_answer_0(callid, EINVAL);
 		return EINVAL;
+	}
 	
 	return async_share_in_finalize(callid, packet,