widelands-dev team mailing list archive

[GunChleoc <fios@xxxxxxxxxxxxxxxxxxx>]

GunChleoc has proposed merging lp:~widelands-dev/widelands/bug-1807156-heap-use-after-free into lp:widelands.

Commit message:
Ensure that interactive base still exists when toggling building help window

This will potentially fix a heap-use-after-free

Requested reviews:
  Widelands Developers (widelands-dev)
Related bugs:
  Bug #1807156 in widelands: "AddressSanitizer: heap-use-after-free"
  https://bugs.launchpad.net/widelands/+bug/1807156

For more details, see:
https://code.launchpad.net/~widelands-dev/widelands/bug-1807156-heap-use-after-free/+merge/363584

I could not reproduce the original bug, so this fix is just my best guess.
-- 
Your team Widelands Developers is requested to review the proposed merge of lp:~widelands-dev/widelands/bug-1807156-heap-use-after-free into lp:widelands.

=== modified file 'src/wui/buildingwindow.cc'
--- src/wui/buildingwindow.cc	2019-02-23 11:00:49 +0000
+++ src/wui/buildingwindow.cc	2019-02-24 07:12:07 +0000
@@ -356,12 +356,14 @@
 		UI::UniqueWindow::Registry& registry =
 		   igbase()->unique_windows().get_registry(building_descr_for_help_.name() + "_help");
 		registry.open_window = [this, &registry] {
-			Widelands::Building* building_in_lambda = building_.get(parent_->egbase());
-			if (building_in_lambda == nullptr) {
-				return;
+			if (parent_ != nullptr) {
+				Widelands::Building* building_in_lambda = building_.get(parent_->egbase());
+				if (building_in_lambda == nullptr) {
+					return;
+				}
+				new UI::BuildingHelpWindow(igbase(), registry, building_descr_for_help_,
+										   building_in_lambda->owner().tribe(), &parent_->egbase().lua());
 			}
-			new UI::BuildingHelpWindow(igbase(), registry, building_descr_for_help_,
-			                           building_in_lambda->owner().tribe(), &parent_->egbase().lua());
 		};
 
 		helpbtn->sigclicked.connect(