xemu/ui/vnc-ws.c
Ding Hui 2ddafce7f7 vnc: fix resource leak when websocket channel error
When we connect to vnc by websocket channel, and disconnect
(maybe by some network exception) before handshake,
qemu will left CLOSE_WAIT socket and never close it

After 04d2529da2 ("ui: convert VNC server to use QIOChannelSocket")
and dd154c4d9f ("io: fix handling of EOF / error conditions in websock GSource"),
the vnc call qio_channel_add_watch only care about G_IO_IN,
but mising G_IO_HUP and G_IO_ERR.
When the websocket channel get EOF or error, it cannot callback,
because the caller ignore the event, that leads to resource leak

We need handle G_IO_HUP and G_IO_ERR event, then cleanup the channel

Fixes: 04d2529da2 ("ui: convert VNC server to use QIOChannelSocket")
Fixes: dd154c4d9f ("io: fix handling of EOF / error conditions in websock GSource")
Cc: qemu-stable@nongnu.org
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Message-id: 20201029032241.11040-1-dinghui@sangfor.com.cn
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-11-04 08:25:17 +01:00

151 lines
4.2 KiB
C

/*
* QEMU VNC display driver: Websockets support
*
* Copyright (C) 2010 Joel Martin
* Copyright (C) 2012 Tim Hardeck
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this software; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "vnc.h"
#include "io/channel-websock.h"
#include "qemu/bswap.h"
#include "trace.h"
static void vncws_tls_handshake_done(QIOTask *task,
gpointer user_data)
{
VncState *vs = user_data;
Error *err = NULL;
if (qio_task_propagate_error(task, &err)) {
VNC_DEBUG("Handshake failed %s\n", error_get_pretty(err));
vnc_client_error(vs);
error_free(err);
} else {
VNC_DEBUG("TLS handshake complete, starting websocket handshake\n");
if (vs->ioc_tag) {
g_source_remove(vs->ioc_tag);
}
vs->ioc_tag = qio_channel_add_watch(
QIO_CHANNEL(vs->ioc), G_IO_IN | G_IO_HUP | G_IO_ERR,
vncws_handshake_io, vs, NULL);
}
}
gboolean vncws_tls_handshake_io(QIOChannel *ioc G_GNUC_UNUSED,
GIOCondition condition,
void *opaque)
{
VncState *vs = opaque;
QIOChannelTLS *tls;
Error *err = NULL;
if (vs->ioc_tag) {
g_source_remove(vs->ioc_tag);
vs->ioc_tag = 0;
}
if (condition & (G_IO_HUP | G_IO_ERR)) {
vnc_client_error(vs);
return TRUE;
}
tls = qio_channel_tls_new_server(
vs->ioc,
vs->vd->tlscreds,
vs->vd->tlsauthzid,
&err);
if (!tls) {
VNC_DEBUG("Failed to setup TLS %s\n", error_get_pretty(err));
error_free(err);
vnc_client_error(vs);
return TRUE;
}
qio_channel_set_name(QIO_CHANNEL(tls), "vnc-ws-server-tls");
object_unref(OBJECT(vs->ioc));
vs->ioc = QIO_CHANNEL(tls);
trace_vnc_client_io_wrap(vs, vs->ioc, "tls");
vs->tls = qio_channel_tls_get_session(tls);
qio_channel_tls_handshake(tls,
vncws_tls_handshake_done,
vs,
NULL,
NULL);
return TRUE;
}
static void vncws_handshake_done(QIOTask *task,
gpointer user_data)
{
VncState *vs = user_data;
Error *err = NULL;
if (qio_task_propagate_error(task, &err)) {
VNC_DEBUG("Websock handshake failed %s\n", error_get_pretty(err));
vnc_client_error(vs);
error_free(err);
} else {
VNC_DEBUG("Websock handshake complete, starting VNC protocol\n");
vnc_start_protocol(vs);
if (vs->ioc_tag) {
g_source_remove(vs->ioc_tag);
}
vs->ioc_tag = qio_channel_add_watch(
vs->ioc, G_IO_IN | G_IO_HUP | G_IO_ERR,
vnc_client_io, vs, NULL);
}
}
gboolean vncws_handshake_io(QIOChannel *ioc G_GNUC_UNUSED,
GIOCondition condition,
void *opaque)
{
VncState *vs = opaque;
QIOChannelWebsock *wioc;
if (vs->ioc_tag) {
g_source_remove(vs->ioc_tag);
vs->ioc_tag = 0;
}
if (condition & (G_IO_HUP | G_IO_ERR)) {
vnc_client_error(vs);
return TRUE;
}
wioc = qio_channel_websock_new_server(vs->ioc);
qio_channel_set_name(QIO_CHANNEL(wioc), "vnc-ws-server-websock");
object_unref(OBJECT(vs->ioc));
vs->ioc = QIO_CHANNEL(wioc);
trace_vnc_client_io_wrap(vs, vs->ioc, "websock");
qio_channel_websock_handshake(wioc,
vncws_handshake_done,
vs,
NULL);
return TRUE;
}