[freetype2] master a660e3d: [type1] Fix heap buffer overflow.

[Werner LEMBERG]

branch: master
commit a660e3de422731b94d4a134d27555430cbb6fb39
Author: Werner Lemberg <address@hidden>
Commit: Werner Lemberg <address@hidden>

    [type1] Fix heap buffer overflow.
    
    Reported as
    
      https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=36
    
    * src/type1/t1load.c (parse_charstrings): Reject fonts that don't
    contain glyph names.
---
 ChangeLog          |   11 +++++++++++
 src/type1/t1load.c |    6 ++++++
 2 files changed, 17 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 07e190e..bbb3d32 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2016-08-26  Werner Lemberg  <address@hidden>
+
+       [type1] Fix heap buffer overflow.
+
+       Reported as
+
+         https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=36
+
+       * src/type1/t1load.c (parse_charstrings): Reject fonts that don't
+       contain glyph names.
+
 2016-08-25  Werner Lemberg  <address@hidden>
 
        [sfnt] Fix previous commit (#48901).
diff --git a/src/type1/t1load.c b/src/type1/t1load.c
index c981adc..f8bf313 100644
--- a/src/type1/t1load.c
+++ b/src/type1/t1load.c
@@ -1776,6 +1776,12 @@
       }
     }
 
+    if ( !n )
+    {
+      error = FT_THROW( Invalid_File_Format );
+      goto Fail;
+    }
+
     loader->num_glyphs = n;
 
     /* if /.notdef is found but does not occupy index 0, do our magic. */