1 files changed, 9 insertions, 1 deletions

diff --git a/scene/resources/surface_tool.cpp b/scene/resources/surface_tool.cpp
index 3d3900ecc5..ff682a40f4 100644
--- a/scene/resources/surface_tool.cpp
+++ b/scene/resources/surface_tool.cpp
@@ -663,6 +663,8 @@ void SurfaceTool::deindex() {
 }
 
 void SurfaceTool::_create_list(const Ref<Mesh> &p_existing, int p_surface, LocalVector<Vertex> *r_vertex, LocalVector<int> *r_index, uint32_t &lformat) {
+	ERR_FAIL_NULL_MSG(p_existing, "First argument in SurfaceTool::_create_list() must be a valid object of type Mesh");
+
 	Array arr = p_existing->surface_get_arrays(p_surface);
 	ERR_FAIL_COND(arr.size() != RS::ARRAY_MAX);
 	_create_list_from_arrays(arr, r_vertex, r_index, lformat);
@@ -824,6 +826,8 @@ void SurfaceTool::create_from_triangle_arrays(const Array &p_arrays) {
 }
 
 void SurfaceTool::create_from(const Ref<Mesh> &p_existing, int p_surface) {
+	ERR_FAIL_NULL_MSG(p_existing, "First argument in SurfaceTool::create_from() must be a valid object of type Mesh");
+
 	clear();
 	primitive = p_existing->surface_get_primitive_type(p_surface);
 	_create_list(p_existing, p_surface, &vertex_array, &index_array, format);
@@ -831,6 +835,8 @@ void SurfaceTool::create_from(const Ref<Mesh> &p_existing, int p_surface) {
 }
 
 void SurfaceTool::create_from_blend_shape(const Ref<Mesh> &p_existing, int p_surface, const String &p_blend_shape_name) {
+	ERR_FAIL_NULL_MSG(p_existing, "First argument in SurfaceTool::create_from_blend_shape() must be a valid object of type Mesh");
+
 	clear();
 	primitive = p_existing->surface_get_primitive_type(p_surface);
 	Array arr = p_existing->surface_get_blend_shape_arrays(p_surface);
@@ -851,6 +857,8 @@ void SurfaceTool::create_from_blend_shape(const Ref<Mesh> &p_existing, int p_sur
 }
 
 void SurfaceTool::append_from(const Ref<Mesh> &p_existing, int p_surface, const Transform &p_xform) {
+	ERR_FAIL_NULL_MSG(p_existing, "First argument in SurfaceTool::append_from() must be a valid object of type Mesh");
+
 	if (vertex_array.size() == 0) {
 		primitive = p_existing->surface_get_primitive_type(p_surface);
 		format = 0;
@@ -1105,7 +1113,7 @@ void SurfaceTool::optimize_indices_for_cache() {
 	ERR_FAIL_COND(index_array.size() == 0);
 
 	LocalVector old_index_array = index_array;
-	zeromem(index_array.ptr(), index_array.size() * sizeof(int));
+	memset(index_array.ptr(), 0, index_array.size() * sizeof(int));
 	optimize_vertex_cache_func((unsigned int *)index_array.ptr(), (unsigned int *)old_index_array.ptr(), old_index_array.size(), vertex_array.size());
 }