LibOverride: Fix crash in ShapeKeys when making a mesh override local.

Weird 'embedded for overrides' flag of embedded IDs (including ShapeKeys
in override context) was not properly cleaned up when making an override
fully local.

Reported by studio, thanks.

@jbakker should be backported to 2.93LTS if possible.

2 files changed, 30 insertions, 2 deletions

diff --git a/source/blender/blenkernel/intern/lib_id.c b/source/blender/blenkernel/intern/lib_id.c
index 6546603ffb4..eeda77771ed 100644
--- a/source/blender/blenkernel/intern/lib_id.c
+++ b/source/blender/blenkernel/intern/lib_id.c
@@ -1917,13 +1917,13 @@ void BKE_library_make_local(Main *bmain,
         ntree->tag &= ~LIB_TAG_DOIT;
       }
 
-      if (id->lib == NULL) {
+      if (!ID_IS_LINKED(id->lib)) {
         id->tag &= ~(LIB_TAG_EXTERN | LIB_TAG_INDIRECT | LIB_TAG_NEW);
         id->flag &= ~LIB_INDIRECT_WEAK_LINK;
         if (ID_IS_OVERRIDE_LIBRARY_REAL(id) &&
             ELEM(lib, NULL, id->override_library->reference->lib) &&
             ((untagged_only == false) || !(id->tag & LIB_TAG_PRE_EXISTING))) {
-          BKE_lib_override_library_free(&id->override_library, true);
+          BKE_lib_override_library_make_local(id);
         }
       }
       /* The check on the fourth line (LIB_TAG_PRE_EXISTING) is done so it's possible to tag data
diff --git a/source/blender/blenkernel/intern/lib_override.c b/source/blender/blenkernel/intern/lib_override.c
index 54d14e33209..fd78e72b9a7 100644
--- a/source/blender/blenkernel/intern/lib_override.c
+++ b/source/blender/blenkernel/intern/lib_override.c
@@ -48,6 +48,7 @@
 #include "BKE_lib_query.h"
 #include "BKE_lib_remap.h"
 #include "BKE_main.h"
+#include "BKE_node.h"
 #include "BKE_report.h"
 #include "BKE_scene.h"
 
@@ -1313,6 +1314,33 @@ void BKE_lib_override_library_delete(Main *bmain, ID *id_root)
   BKE_main_id_tag_all(bmain, LIB_TAG_DOIT, false);
 }
 
+/** Make given ID fully local.
+ *
+ *  \note Only differs from lower-level `BKE_lib_override_library_free in infamous embedded ID
+ *        cases.
+ */
+void BKE_lib_override_library_make_local(ID *id)
+{
+  BKE_lib_override_library_free(&id->override_library, true);
+
+  Key *shape_key = BKE_key_from_id(id);
+  if (shape_key != NULL) {
+    shape_key->id.flag &= ~LIB_EMBEDDED_DATA_LIB_OVERRIDE;
+  }
+
+  if (GS(id->name) == ID_SCE) {
+    Collection *master_collection = ((Scene *)id)->master_collection;
+    if (master_collection != NULL) {
+      master_collection->id.flag &= ~LIB_EMBEDDED_DATA_LIB_OVERRIDE;
+    }
+  }
+
+  bNodeTree *node_tree = ntreeFromID(id);
+  if (node_tree != NULL) {
+    node_tree->id.flag &= ~LIB_EMBEDDED_DATA_LIB_OVERRIDE;
+  }
+}
+
 BLI_INLINE IDOverrideLibraryRuntime *override_library_rna_path_runtime_ensure(
     IDOverrideLibrary *override)
 {