Fix T100016: Memory leak in USD importer.

These changes were implemented by Sonny Campbell.

Fixed the first issue by freeing the operator customdata when the import
is cancelled.

Fixed the second issue by using a character array instead of allocating
new memory for the prim_path_mask.

Differential Revision: https://developer.blender.org/D15781

2 files changed, 24 insertions, 3 deletions

diff --git a/source/blender/editors/io/io_usd.c b/source/blender/editors/io/io_usd.c
index ba118a5e289..534ba813743 100644
--- a/source/blender/editors/io/io_usd.c
+++ b/source/blender/editors/io/io_usd.c
@@ -191,6 +191,19 @@ static void wm_usd_export_draw(bContext *UNUSED(C), wmOperator *op)
   uiItemR(box, ptr, "use_instancing", 0, NULL, ICON_NONE);
 }
 
+static void free_operator_customdata(wmOperator *op)
+{
+  if (op->customdata) {
+    MEM_freeN(op->customdata);
+    op->customdata = NULL;
+  }
+}
+
+static void wm_usd_export_cancel(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  free_operator_customdata(op);
+}
+
 static bool wm_usd_export_check(bContext *UNUSED(C), wmOperator *op)
 {
   char filepath[FILE_MAX];
@@ -215,6 +228,7 @@ void WM_OT_usd_export(struct wmOperatorType *ot)
   ot->exec = wm_usd_export_exec;
   ot->poll = WM_operator_winactive;
   ot->ui = wm_usd_export_draw;
+  ot->cancel = wm_usd_export_cancel;
   ot->check = wm_usd_export_check;
 
   ot->flag = OPTYPE_REGISTER | OPTYPE_PRESET; /* No UNDO possible. */
@@ -360,7 +374,7 @@ static int wm_usd_import_exec(bContext *C, wmOperator *op)
 
   const bool create_collection = RNA_boolean_get(op->ptr, "create_collection");
 
-  char *prim_path_mask = malloc(1024);
+  char prim_path_mask[1024];
   RNA_string_get(op->ptr, "prim_path_mask", prim_path_mask);
 
   const bool import_guide = RNA_boolean_get(op->ptr, "import_guide");
@@ -402,7 +416,6 @@ static int wm_usd_import_exec(bContext *C, wmOperator *op)
                                    .import_materials = import_materials,
                                    .import_meshes = import_meshes,
                                    .import_volumes = import_volumes,
-                                   .prim_path_mask = prim_path_mask,
                                    .import_subdiv = import_subdiv,
                                    .import_instance_proxies = import_instance_proxies,
                                    .create_collection = create_collection,
@@ -416,11 +429,18 @@ static int wm_usd_import_exec(bContext *C, wmOperator *op)
                                    .light_intensity_scale = light_intensity_scale,
                                    .mtl_name_collision_mode = mtl_name_collision_mode};
 
+  STRNCPY(params.prim_path_mask, prim_path_mask);
+
   const bool ok = USD_import(C, filename, &params, as_background_job);
 
   return as_background_job || ok ? OPERATOR_FINISHED : OPERATOR_CANCELLED;
 }
 
+static void wm_usd_import_cancel(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  free_operator_customdata(op);
+}
+
 static void wm_usd_import_draw(bContext *UNUSED(C), wmOperator *op)
 {
   uiLayout *layout = op->layout;
@@ -476,6 +496,7 @@ void WM_OT_usd_import(struct wmOperatorType *ot)
 
   ot->invoke = wm_usd_import_invoke;
   ot->exec = wm_usd_import_exec;
+  ot->cancel = wm_usd_import_cancel;
   ot->poll = WM_operator_winactive;
   ot->ui = wm_usd_import_draw;
 
diff --git a/source/blender/io/usd/usd.h b/source/blender/io/usd/usd.h
index a07315d8b4e..3494d8ffdc3 100644
--- a/source/blender/io/usd/usd.h
+++ b/source/blender/io/usd/usd.h
@@ -52,7 +52,7 @@ struct USDImportParams {
   bool import_materials;
   bool import_meshes;
   bool import_volumes;
-  char *prim_path_mask;
+  char prim_path_mask[1024];
   bool import_subdiv;
   bool import_instance_proxies;
   bool create_collection;