win: Prevent crash inside ecore evas callbacks

After any complex call on the window, a foreign evas/efl callback may be
triggered that could delete the window object. This leads to crashes in
queued jobs or even immediately after said callback (right now EO
prevents immediate memory free using eina_freeq or eina_trash so the
effects aren't immediate).

Funnily enough, this was a known issue according to some comments, but
no one bothered fixing it...

In this particular instance, a focus_out job was crashing while trying
to access now-invalid sd data.

I believe some uses of ELM_WIN_DATA_GET() may still be slightly unsafe
but most look like they should be the result of an EO call on the object
(eg. a call to efl_event_callback_call), which ensures the object is
alive.

Fixes T5869

diff --git a/src/lib/elementary/efl_ui_win.c b/src/lib/elementary/efl_ui_win.c
index f7f394b..3643a3d 100644 (file)
--- a/src/lib/elementary/efl_ui_win.c
+++ b/src/lib/elementary/efl_ui_win.c
@@ -59,6 +59,14 @@ static const Elm_Win_Trap *trap = NULL;
        return __VA_ARGS__;                           \
     }
 
+// Ecore_Evas callbacks are unsafe unlike EO calls. As a consequence a user
+// callback (eg evas cb, efl event cb, ...) could be triggered that deletes the
+// object. This macro ensures the sd data is still valid after a foreign call.
+#define ELM_WIN_DATA_ALIVE_CHECK(_obj, _sd, ...) do { \
+   _sd = efl_data_scope_safe_get(_obj, MY_CLASS); \
+   if (EINA_UNLIKELY(!(_sd))) { return __VA_ARGS__; } \
+   } while (0)
+
 #define ENGINE_GET() (_elm_preferred_engine ? _elm_preferred_engine : _elm_config->engine)
 
 typedef struct _Efl_Ui_Win_Data Efl_Ui_Win_Data;
@@ -800,9 +808,7 @@ static Efl_Ui_Win_Data *
 _elm_win_associate_get(const Ecore_Evas *ee)
 {
    Evas_Object *obj = ecore_evas_data_get(ee, "elm_win");
-   if (!obj) return NULL;
-   ELM_WIN_DATA_GET(obj, sd);
-   return sd;
+   return efl_data_scope_safe_get(obj, MY_CLASS);
 }
 
 /* Interceptors Callbacks */
@@ -871,17 +877,21 @@ _elm_win_move(Ecore_Evas *ee)
 {
    Efl_Ui_Win_Data *sd = _elm_win_associate_get(ee);
    int x, y;
+   Eo *obj;
 
    if (!sd) return;
+   obj = sd->obj;
 
    ecore_evas_geometry_get(ee, &x, &y, NULL, NULL);
    sd->screen.x = x;
    sd->screen.y = y;
    efl_event_callback_legacy_call(sd->obj, EFL_GFX_EVENT_MOVE, NULL);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    evas_nochange_push(evas_object_evas_get(sd->obj));
    sd->response++;
    sd->req_xy = EINA_FALSE;
    evas_object_move(sd->obj, x, y);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    sd->response--;
    evas_nochange_pop(evas_object_evas_get(sd->obj));
 }
@@ -932,13 +942,17 @@ static void
 _elm_win_pre_render(Ecore_Evas *ee)
 {
    Efl_Ui_Win_Data *sd = _elm_win_associate_get(ee);
+   Eo *obj;
+
    if (!sd) return;
+   obj = sd->obj;
 
    _elm_win_throttle_ok = EINA_TRUE;
    if (!sd->first_draw)
      {
         sd->first_draw = EINA_TRUE;
         _elm_win_frame_obj_update(sd);
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
      }
    if (sd->deferred_resize_job)
      _elm_win_resize_job(sd->obj);
@@ -967,6 +981,7 @@ _elm_win_mouse_in(Ecore_Evas *ee)
         sd->pointer.visible = EINA_TRUE;
         sd->pointer.surf = ecore_wl2_window_surface_get(sd->pointer.win);
         _elm_win_wl_cursor_set(sd->obj, NULL);
+        //ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         ecore_evas_show(sd->pointer.ee);
      }
 #endif
@@ -1207,6 +1222,7 @@ _elm_win_focus_in(Ecore_Evas *ee)
    obj = sd->obj;
 
    _elm_widget_top_win_focused_set(obj, EINA_TRUE);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    if (sd->type != ELM_WIN_FAKE)
      {
         if (!elm_widget_focus_order_get(obj))
@@ -1227,9 +1243,9 @@ _elm_win_focus_in(Ecore_Evas *ee)
                evas_object_focus_set(obj, EINA_TRUE);
           }
      }
-   // FIXME: the event is deprecated but still in use.
-   // Has to be removed in EFL2.0
+
    evas_object_smart_callback_call(obj, SIG_FOCUS_IN, NULL);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    sd->focus_highlight.cur.visible = EINA_TRUE;
    _elm_win_focus_highlight_reconfigure_job_start(sd);
    _elm_win_frame_style_update(sd, 0, 1);
@@ -1257,9 +1273,9 @@ _elm_win_focus_out(Ecore_Evas *ee)
    obj = sd->obj;
 
    _elm_widget_top_win_focused_set(obj, EINA_FALSE);
-   // FIXME: the event is deprecated but still in use.
-   // Has to be removed in EFL2.0
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    evas_object_smart_callback_call(obj, SIG_FOCUS_OUT, NULL);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    sd->focus_highlight.cur.visible = EINA_FALSE;
    _elm_win_focus_highlight_reconfigure_job_start(sd);
    if (!sd->resizing)
@@ -1523,6 +1539,7 @@ _elm_win_state_change(Ecore_Evas *ee)
         ch_profile = _internal_elm_win_profile_set(sd, profile);
      }
 
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    if (sd->wm_rot.use)
      {
         if (sd->rot != ecore_evas_rotation_get(sd->ee))
@@ -1536,6 +1553,7 @@ _elm_win_state_change(Ecore_Evas *ee)
 
    if ((ch_withdrawn) || (ch_iconified))
      {
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         if (sd->withdrawn)
           efl_event_callback_legacy_call(obj, EFL_UI_WIN_EVENT_WITHDRAWN, NULL);
         else if (sd->iconified)
@@ -1567,6 +1585,7 @@ _elm_win_state_change(Ecore_Evas *ee)
 #endif
    if (ch_fullscreen)
      {
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         _elm_win_frame_style_update(sd, 0, 1);
         if (sd->fullscreen)
           {
@@ -1582,6 +1601,7 @@ _elm_win_state_change(Ecore_Evas *ee)
      }
    if (ch_maximized)
      {
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         _elm_win_frame_style_update(sd, 0, 1);
         if (sd->maximized)
           {
@@ -1598,6 +1618,7 @@ _elm_win_state_change(Ecore_Evas *ee)
      }
    if (ch_profile)
      {
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         _elm_win_profile_update(sd);
      }
    if (ch_wm_rotation)
@@ -1605,8 +1626,10 @@ _elm_win_state_change(Ecore_Evas *ee)
         efl_gfx_size_hint_restricted_min_set(obj, -1, -1);
         efl_gfx_size_hint_max_set(obj, -1, -1);
 #ifdef HAVE_ELEMENTARY_X
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         _elm_win_xwin_update(sd);
 #endif
+        ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
         elm_widget_orientation_set(obj, sd->rot);
         efl_event_callback_legacy_call
           (obj, EFL_UI_WIN_EVENT_ROTATION_CHANGED, NULL);
@@ -3026,11 +3049,13 @@ _elm_win_delete_request(Ecore_Evas *ee)
    sd->autodel_clear = &autodel;
    evas_object_ref(obj);
    efl_event_callback_legacy_call(obj, EFL_UI_WIN_EVENT_DELETE_REQUEST, NULL);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    if (sd->autohide)
      evas_object_hide(obj);
-   // FIXME: if above callback deletes - then the below will be invalid
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    if (_elm_config->atspi_mode)
      elm_interface_atspi_window_destroyed_signal_emit(obj);
+   ELM_WIN_DATA_ALIVE_CHECK(obj, sd);
    if (autodel) evas_object_del(obj);
    else sd->autodel_clear = NULL;
    evas_object_unref(obj);