[PATCH] touch-input: Don't dereference NULL pointer during full screen fade

[Derek Foreman]

If a full screen program is fading out and a touch start happens, it
will result in a NULL pointer dereference when weston_touch_set_focus
tries to derefernce view->surface->resource.

Instead, this patch sets the focus to NULL, which should be the
same as if the program was destroyed during the touch anyway.

An additional test for NULL focus is added to prevent touch bindings
from firing without a focus.

Closes bug 78706
---
 src/input.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/input.c b/src/input.c
index 975cd77..bcd603b 100644
--- a/src/input.c
+++ b/src/input.c
@@ -1419,8 +1419,14 @@ weston_touch_set_focus(struct weston_seat *seat, struct weston_view *view)
 	}
 
 	if (view) {
-		struct wl_client *surface_client =
-			wl_resource_get_client(view->surface->resource);
+		struct wl_client *surface_client;
+
+		if (!view->surface->resource) {
+			seat->touch->focus = NULL;
+			return;
+		}
+
+		surface_client = wl_resource_get_client(view->surface->resource);
 		move_resources_for_client(focus_resource_list,
 					  &seat->touch->resource_list,
 					  surface_client);
@@ -1479,8 +1485,9 @@ notify_touch(struct weston_seat *seat, uint32_t time, int touch_id,
 			return;
 		}
 
-		weston_compositor_run_touch_binding(ec, seat,
-						    time, touch_type);
+		if (seat->touch->focus)
+			weston_compositor_run_touch_binding(ec, seat,
+							    time, touch_type);
 
 		grab->interface->down(grab, time, touch_id, sx, sy);
 		if (touch->num_tp == 1) {
-- 
2.1.0.rc1