* src/base/ftbitmap.c (FT_Bitmap_Blend): Avoid integer overflow.

7 years ago · 9d8e6c2980
parent 68bc56f864
commit 9d8e6c2980
2 changed files with 9 additions and 2 deletions
--- a/4
+++ b/4
@ -1,3 +1,7 @@
+2018-06-16  Werner Lemberg  <wl@gnu.org>
+
+	* src/base/ftbitmap.c (FT_Bitmap_Blend): Avoid integer overflow.
+
 2018-06-16  Werner Lemberg  <wl@gnu.org>

 	Add `FT_Bitmap_Blend' API.
--- a/src/base/ftbitmap.c
+++ b/src/base/ftbitmap.c
@ -901,8 +901,11 @@
    source_llx -= final_llx;
    source_lly -= final_lly;

-    target_llx -= final_llx;
-    target_lly -= final_lly;
+    if ( target->width && target->rows )
+    {
+      target_llx -= final_llx;
+      target_lly -= final_lly;
+    }

    /* set up target bitmap */
    if ( target->pixel_mode == FT_PIXEL_MODE_NONE )