Commit 9cca7578 authored Oct 05, 2017 by Daniel P. Berrangé Committed by Paolo Bonzini Oct 12, 2017

char: don't skip client cleanup if 'connected' flag is unset



The tcp_chr_free_connection & tcp_chr_disconnect methods both
skip all of their cleanup work unless the 's->connected' flag
is set.  This flag is set when the incoming client connection
is ready to use. Crucially this is *after* the TLS handshake
has been completed. So if the TLS handshake fails and we try
to cleanup the failed client, all the cleanup is skipped as
's->connected' is still false.

The only important thing that should be skipped in this case
is sending of the CHR_EVENT_CLOSED, because we never got as
far as sending the corresponding CHR_EVENT_OPENED. Every other
bit of cleanup can be robust against being called even when
s->connected is false.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20171005155057.7664-1-berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 3b19f450

chardev/char-socket.c

+9 −10

Original line number	Diff line number	Diff line
		@@ -332,10 +332,6 @@ static void tcp_chr_free_connection(Chardev *chr)
		SocketChardev *s = SOCKET_CHARDEV(chr);
		int i;

		if (!s->connected) {
		return;
		}

		if (s->read_msgfds_num) {
		for (i = 0; i < s->read_msgfds_num; i++) {
		close(s->read_msgfds[i]);
		@@ -394,22 +390,25 @@ static void update_disconnected_filename(SocketChardev *s)
		s->is_listen, s->is_telnet);
		}

		/* NB may be called even if tcp_chr_connect has not been
		* reached, due to TLS or telnet initialization failure,
		* so can not assume s->connected == true
		*/
		static void tcp_chr_disconnect(Chardev *chr)
		{
		SocketChardev *s = SOCKET_CHARDEV(chr);

		if (!s->connected) {
		return;
		}
		bool emit_close = s->connected;

		tcp_chr_free_connection(chr);

		if (s->listen_ioc) {
		if (s->listen_ioc && s->listen_tag == 0) {
		s->listen_tag = qio_channel_add_watch(
		QIO_CHANNEL(s->listen_ioc), G_IO_IN, tcp_chr_accept, chr, NULL);
		}
		update_disconnected_filename(s);
		if (emit_close) {
		qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
		}
		if (s->reconnect_time) {
		qemu_chr_socket_restart_timer(chr);
		}