xcb: check validity of RandR output info before using it

Fixes: QTBUG-128906 Pick-to: 6.8 6.7 6.5 6.2 5.15 Change-Id: Ibafdf4bb9c449b29437b0520299ab407238e5703 Reviewed-by: Tor Arne Vestbø <[email protected]>
qt · Sep 20, 2024 · 439e19b · 439e19b
1 parent 1c9a785
commit 439e19b
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/plugins/platforms/xcb/qxcbconnection_screens.cpp b/src/plugins/platforms/xcb/qxcbconnection_screens.cpp
@@ -140,7 +140,7 @@ void QXcbConnection::updateScreens(const xcb_randr_notify_event_t *event)
                 // Screen has been disabled
                 auto outputInfo = Q_XCB_REPLY(xcb_randr_get_output_info, xcb_connection(),
                                               output.output, output.config_timestamp);
-                if (outputInfo->crtc == XCB_NONE) {
+                if (!outputInfo || outputInfo->crtc == XCB_NONE) {
                     qCDebug(lcQpaScreen) << "output" << screen->name() << "has been disabled";
                     destroyScreen(screen);
                 } else {