[freetype2] gsoc-anurag-2022 08e08f590: Fix monochrome crash

[Werner Lemberg]

branch: gsoc-anurag-2022
commit 08e08f590807a4bc99b5cd1257c8aeace1ca9538
Author: Anurag Thakur <anurag105csec21@bpitindia.edu.in>
Commit: Anurag Thakur <anurag105csec21@bpitindia.edu.in>

    Fix monochrome crash
---
 src/dense/ftdenserend.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/dense/ftdenserend.c b/src/dense/ftdenserend.c
index cd2aeeb4c..903527bff 100644
--- a/src/dense/ftdenserend.c
+++ b/src/dense/ftdenserend.c
@@ -75,6 +75,15 @@ take a variable named `memory`. It can only be known if you 
follow the macros 3
     goto Exit;
   }
 
+      /* check mode */
+    if ( mode != FT_RENDER_MODE_NORMAL &&
+         mode != FT_RENDER_MODE_LIGHT  &&
+         mode != FT_RENDER_MODE_LCD    &&
+         mode != FT_RENDER_MODE_LCD_V  )
+    {
+      error = FT_THROW( Cannot_Render_Glyph );
+      goto Exit;
+    }
 
   /* deallocate the previously allocated bitmap */
   if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )