[Bf-blender-cvs] [65b414cfb29] blender-v2.81-release: Fix T71319, T71015: crash in edit mode with out of range material assignments

[Brecht Van Lommel]

Commit: 65b414cfb291e8ae47e92ab1b101de3fa6d19704
Author: Brecht Van Lommel
Date:   Wed Nov 6 16:06:57 2019 +0100
Branches: blender-v2.81-release
https://developer.blender.org/rB65b414cfb291e8ae47e92ab1b101de3fa6d19704

Fix T71319, T71015: crash in edit mode with out of range material assignments

===================================================================

M	source/blender/draw/intern/draw_cache_extract_mesh.c

===================================================================

diff --git a/source/blender/draw/intern/draw_cache_extract_mesh.c b/source/blender/draw/intern/draw_cache_extract_mesh.c
index fb439016a87..c30cf9f6328 100644
--- a/source/blender/draw/intern/draw_cache_extract_mesh.c
+++ b/source/blender/draw/intern/draw_cache_extract_mesh.c
@@ -484,7 +484,7 @@ static void *extract_tris_init(const MeshRenderData *mr, void *UNUSED(ibo))
   return data;
 }
 
-static void extract_tris_looptri_bmesh(const MeshRenderData *UNUSED(mr),
+static void extract_tris_looptri_bmesh(const MeshRenderData *mr,
                                        int UNUSED(t),
                                        BMLoop **elt,
                                        void *_data)
@@ -492,8 +492,9 @@ static void extract_tris_looptri_bmesh(const MeshRenderData *UNUSED(mr),
   if (!BM_elem_flag_test(elt[0]->f, BM_ELEM_HIDDEN)) {
     MeshExtract_Tri_Data *data = _data;
     int *mat_tri_ofs = data->tri_mat_end;
+    int mat = min_ii(elt[0]->f->mat_nr, mr->mat_len - 1);
     GPU_indexbuf_set_tri_verts(&data->elb,
-                               mat_tri_ofs[elt[0]->f->mat_nr]++,
+                               mat_tri_ofs[mat]++,
                                BM_elem_index_get(elt[0]),
                                BM_elem_index_get(elt[1]),
                                BM_elem_index_get(elt[2]));