fix chunk predicate use-after-free

2 files changed, 16 insertions, 17 deletions

diff --git a/src/chunk-region.cpp b/src/chunk-region.cpp
index 67c474bc..54696bc0 100644
--- a/src/chunk-region.cpp
+++ b/src/chunk-region.cpp
@@ -111,26 +111,15 @@ tmp_s& get_tmp()
     return *tmp;
 }
 
-} // namespace
-
-void chunk::delete_pass_region(pass_region*& ptr)
-{
-    if (ptr)
-    {
-        delete ptr;
-        ptr = nullptr;
-    }
-}
-
-pred chunk::default_region_predicate() noexcept
+auto default_region_predicate(chunk& c) noexcept
 {
-    return [this](collision_data data) {
+    return [&c](collision_data data) {
         auto x = std::bit_cast<collision_data>(data);
         // XXX 'scenery' is used for all object types
         if (x.tag == (uint64_t)collision_type::scenery)
         {
-            auto& w = _world;
-            auto obj = w->find_object(x.data);
+            auto& w = c.world();
+            auto obj = w.find_object(x.data);
             if (obj->type() == object_type::critter)
                 return path_search_continue::pass;
         }
@@ -138,6 +127,17 @@ pred chunk::default_region_predicate() noexcept
     };
 }
 
+} // namespace
+
+void chunk::delete_pass_region(pass_region*& ptr)
+{
+    if (ptr)
+    {
+        delete ptr;
+        ptr = nullptr;
+    }
+}
+
 auto chunk::get_pass_region() -> const pass_region*
 {
     if (!_region_modified)
@@ -161,7 +161,7 @@ void chunk::mark_region_modified() noexcept { _region_modified = true; }
 
 void chunk::make_pass_region(pass_region& ret)
 {
-    return make_pass_region(ret, default_region_predicate());
+    return make_pass_region(ret, default_region_predicate(*this));
 }
 
 void chunk::make_pass_region(pass_region& ret, const pred& f)
diff --git a/src/chunk.hpp b/src/chunk.hpp
index cc48bb26..217bd35a 100644
--- a/src/chunk.hpp
+++ b/src/chunk.hpp
@@ -119,7 +119,6 @@ public:
     static constexpr size_t max_wall_quad_count =
         TILE_COUNT*Wall::Direction_COUNT*(Wall::Group_COUNT+4);
 
-    detail_astar::pred default_region_predicate() noexcept;
     const pass_region* get_pass_region();
     void make_pass_region(pass_region& ret);
     void make_pass_region(pass_region& ret, const detail_astar::pred& f);