From 7b2569933316ec9bec0988711607588f5f8f5a36 Mon Sep 17 00:00:00 2001
From: Hans Goudey <hans@blender.org>
Date: Fri, 8 Mar 2024 20:55:43 -0500
Subject: [PATCH] Fix #119232: Crash on Generate Data Layers in DataTransfer
 modifier

"r_map" is null for the generate layers operator (rather than the modifier
evaluation). It should disable the creation of the "CD_NORMAL" layer too,
like the crease, bevel weight, sharp edge, and uv seam attributes above.
---
 .../blenkernel/intern/data_transfer.cc        | 42 ++++++++++---------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/source/blender/blenkernel/intern/data_transfer.cc b/source/blender/blenkernel/intern/data_transfer.cc
index 713e8106939..b339b75ec9b 100644
--- a/source/blender/blenkernel/intern/data_transfer.cc
+++ b/source/blender/blenkernel/intern/data_transfer.cc
@@ -1052,27 +1052,29 @@ static bool data_transfer_layersmapping_generate(ListBase *r_map,
       cddata_type = CD_PROP_FLOAT2;
     }
     else if (cddata_type == CD_FAKE_LNOR) {
-      /* Use #CD_NORMAL as a temporary storage for custom normals in 3D vector form.
-       * A post-process step will convert this layer to #CD_CUSTOMLOOPNORMAL. */
-      float3 *dst_data = static_cast<float3 *>(
-          CustomData_get_layer_for_write(&me_dst->corner_data, CD_NORMAL, me_dst->corners_num));
-      if (!dst_data) {
-        dst_data = static_cast<float3 *>(CustomData_add_layer(
-            &me_dst->corner_data, CD_NORMAL, CD_SET_DEFAULT, me_dst->corners_num));
+      if (r_map) {
+        /* Use #CD_NORMAL as a temporary storage for custom normals in 3D vector form.
+         * A post-process step will convert this layer to #CD_CUSTOMLOOPNORMAL. */
+        float3 *dst_data = static_cast<float3 *>(
+            CustomData_get_layer_for_write(&me_dst->corner_data, CD_NORMAL, me_dst->corners_num));
+        if (!dst_data) {
+          dst_data = static_cast<float3 *>(CustomData_add_layer(
+              &me_dst->corner_data, CD_NORMAL, CD_SET_DEFAULT, me_dst->corners_num));
+        }
+        if (mix_factor != 1.0f || mix_weights) {
+          MutableSpan(dst_data, me_dst->corners_num).copy_from(me_dst->corner_normals());
+        }
+        /* Post-process will convert it back to CD_CUSTOMLOOPNORMAL. */
+        data_transfer_layersmapping_add_item_cd(r_map,
+                                                CD_NORMAL,
+                                                mix_mode,
+                                                mix_factor,
+                                                mix_weights,
+                                                me_src->corner_normals().data(),
+                                                dst_data,
+                                                customdata_data_transfer_interp_normal_normals,
+                                                space_transform);
       }
-      if (mix_factor != 1.0f || mix_weights) {
-        MutableSpan(dst_data, me_dst->corners_num).copy_from(me_dst->corner_normals());
-      }
-      /* Post-process will convert it back to CD_CUSTOMLOOPNORMAL. */
-      data_transfer_layersmapping_add_item_cd(r_map,
-                                              CD_NORMAL,
-                                              mix_mode,
-                                              mix_factor,
-                                              mix_weights,
-                                              me_src->corner_normals().data(),
-                                              dst_data,
-                                              customdata_data_transfer_interp_normal_normals,
-                                              space_transform);
       return true;
     }