@samitouri / QOSamiQemu / commits / d39d0f3acd

io: fix cleanup for TLS I/O source data on cancellation

The TLS code will create a GSource for tracking completion of the handshake process, passing a QIOChannelTLSData struct that contains various data items. The data struct is freed by the callback when it completes, which means when a source is cancelled, nothing is free'ing the data struct or its contents. Switch to provide a data free callback to the GSource, which ensures the QIOChannelTLSData struct is always freed even when the main event callback never fires. Fixes: https://gitlab.com/qemu-project/qemu/-/issues/3114 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

Daniel P. Berrangé committed Jan 6, 2026 at 13:45 UTC d39d0f3acdd7c1bb275db7e97b511f98254ecd9f
1 file changed +43 -25
io/channel-tls.c
+43 -25
@@ -153,13 +153,32 @@ struct QIOChannelTLSData {
153 };
154 typedef struct QIOChannelTLSData QIOChannelTLSData;
155
156 +static void qio_channel_tls_io_data_free(gpointer user_data)
157 +{
158 + QIOChannelTLSData *data = user_data;
159 + /*
160 + * Usually 'task' will be NULL since the GSource
161 + * callback will either complete the task or pass
162 + * it on to a new GSource. We'll see a non-NULL
163 + * task here only if the GSource was released before
164 + * its callback triggers
165 + */
166 + if (data->task) {
167 + qio_task_free(data->task);
168 + }
169 + if (data->context) {
170 + g_main_context_unref(data->context);
171 + }
172 + g_free(data);
173 +}
174 +
175 static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc,
176 GIOCondition condition,
177 gpointer user_data);
178
160 -static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
161 - QIOTask *task,
162 - GMainContext *context)
179 +static gboolean qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
180 + QIOTask *task,
181 + GMainContext *context)
182 {
183 Error *err = NULL;
184 int status;
@@ -170,8 +189,7 @@ static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
189 trace_qio_channel_tls_handshake_fail(ioc);
190 qio_task_set_error(task, err);
191 qio_task_complete(task);
173 - qio_task_free(task);
174 - return;
192 + return TRUE;
193 }
194
195 if (status == QCRYPTO_TLS_HANDSHAKE_COMPLETE) {
@@ -184,7 +202,7 @@ static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
202 trace_qio_channel_tls_credentials_allow(ioc);
203 }
204 qio_task_complete(task);
187 - qio_task_free(task);
205 + return TRUE;
206 } else {
207 GIOCondition condition;
208 QIOChannelTLSData *data = g_new0(typeof(*data), 1);
@@ -208,8 +226,9 @@ static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
226 condition,
227 qio_channel_tls_handshake_io,
228 data,
211 - NULL,
229 + qio_channel_tls_io_data_free,
230 context);
231 + return FALSE;
232 }
233 }
234
@@ -225,11 +244,9 @@ static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc,
244 qio_task_get_source(task));
245
246 tioc->hs_ioc_tag = 0;
228 - g_free(data);
229 - qio_channel_tls_handshake_task(tioc, task, context);
230 -
231 - if (context) {
232 - g_main_context_unref(context);
247 + if (!qio_channel_tls_handshake_task(tioc, task, context)) {
248 + /* task is kept by new GSource so must not be released yet */
249 + data->task = NULL;
250 }
251
252 return FALSE;
@@ -252,14 +269,16 @@ void qio_channel_tls_handshake(QIOChannelTLS *ioc,
269 func, opaque, destroy);
270
271 trace_qio_channel_tls_handshake_start(ioc);
255 - qio_channel_tls_handshake_task(ioc, task, context);
272 + if (qio_channel_tls_handshake_task(ioc, task, context)) {
273 + qio_task_free(task);
274 + }
275 }
276
277 static gboolean qio_channel_tls_bye_io(QIOChannel *ioc, GIOCondition condition,
278 gpointer user_data);
279
261 -static void qio_channel_tls_bye_task(QIOChannelTLS *ioc, QIOTask *task,
262 - GMainContext *context)
280 +static gboolean qio_channel_tls_bye_task(QIOChannelTLS *ioc, QIOTask *task,
281 + GMainContext *context)
282 {
283 GIOCondition condition;
284 QIOChannelTLSData *data;
@@ -272,14 +291,12 @@ static void qio_channel_tls_bye_task(QIOChannelTLS *ioc, QIOTask *task,
291 trace_qio_channel_tls_bye_fail(ioc);
292 qio_task_set_error(task, err);
293 qio_task_complete(task);
275 - qio_task_free(task);
276 - return;
294 + return TRUE;
295 }
296
297 if (status == QCRYPTO_TLS_BYE_COMPLETE) {
298 qio_task_complete(task);
281 - qio_task_free(task);
282 - return;
299 + return TRUE;
300 }
301
302 data = g_new0(typeof(*data), 1);
@@ -299,7 +316,10 @@ static void qio_channel_tls_bye_task(QIOChannelTLS *ioc, QIOTask *task,
316 trace_qio_channel_tls_bye_pending(ioc, status);
317 ioc->bye_ioc_tag = qio_channel_add_watch_full(ioc->master, condition,
318 qio_channel_tls_bye_io,
302 - data, NULL, context);
319 + data,
320 + qio_channel_tls_io_data_free,
321 + context);
322 + return FALSE;
323 }
324
325
@@ -312,11 +332,9 @@ static gboolean qio_channel_tls_bye_io(QIOChannel *ioc, GIOCondition condition,
332 QIOChannelTLS *tioc = QIO_CHANNEL_TLS(qio_task_get_source(task));
333
334 tioc->bye_ioc_tag = 0;
315 - g_free(data);
316 - qio_channel_tls_bye_task(tioc, task, context);
317 -
318 - if (context) {
319 - g_main_context_unref(context);
335 + if (!qio_channel_tls_bye_task(tioc, task, context)) {
336 + /* task is kept by new GSource so must not be released yet */
337 + data->task = NULL;
338 }
339
340 return FALSE;