Discard a packet that exceeds the receive buffer

src/libcharon/plugins/socket_default/socket_default_socket.c

@@ -212,6 +212,11 @@ METHOD(socket_t, receiver, status_t,
 			DBG1(DBG_NET, "error reading socket: %s", strerror(errno));
 			return FAILED;
 		}
+		if (msg.msg_flags & MSG_TRUNC)
+		{
+			DBG1(DBG_NET, "receive buffer too small, packet discarded");
+			return FAILED;
+		}
 		DBG3(DBG_NET, "received packet %b", buffer, bytes_read);
 
 		if (bytes_read < MARKER_LEN)

src/libcharon/plugins/socket_dynamic/socket_dynamic_socket.c

@@ -229,6 +229,11 @@ static packet_t *receive_packet(private_socket_dynamic_socket_t *this,
 		DBG1(DBG_NET, "error reading socket: %s", strerror(errno));
 		return NULL;
 	}
+	if (msg.msg_flags & MSG_TRUNC)
+	{
+		DBG1(DBG_NET, "receive buffer too small, packet discarded");
+		return NULL;
+	}
 	DBG3(DBG_NET, "received packet %b", buffer, len);
 
 	if (len < MARKER_LEN)

src/libcharon/plugins/socket_raw/socket_raw_socket.c

@@ -172,6 +172,11 @@ METHOD(socket_t, receiver, status_t,
 			DBG1(DBG_NET, "error reading from IPv4 socket: %s", strerror(errno));
 			return FAILED;
 		}
+		if (bytes_read == this->max_packet)
+		{
+			DBG1(DBG_NET, "receive buffer too small, packet discarded");
+			return FAILED;
+		}
 		DBG3(DBG_NET, "received IPv4 packet %b", buffer, bytes_read);
 
 		/* read source/dest from raw IP/UDP header */