From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 20 Aug 2023 20:25:02 +0000 (+0300)
Subject: Clear saved input focus if the widget is removed from the container
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgltk.git;a=commitdiff_plain;h=ab45b7660aec83978871ade009846dcb8c34579f

Clear saved input focus if the widget is removed from the container

Checking the saved focus widget's parent in focus_in can lead to use
after free if the widget was deleted in the meantime.
---

diff --git a/source/container.cpp b/source/container.cpp
index 393973c..9ef46f1 100644
--- a/source/container.cpp
+++ b/source/container.cpp
@@ -35,6 +35,8 @@ void Container::remove(Widget &wdg)
 	if(i==children.end())
 		throw hierarchy_error("widget not in container");
 
+	if(&wdg==saved_input_focus)
+		saved_input_focus = nullptr;
 	wdg.set_parent(nullptr);
 	delete *i;
 	children.erase(i);
@@ -317,7 +319,7 @@ bool Container::character(wchar_t ch)
 
 void Container::focus_in()
 {
-	if(saved_input_focus && saved_input_focus->get_parent()==this)
+	if(saved_input_focus)
 		set_input_focus(saved_input_focus);
 	Widget::focus_in();
 }