[freetype2] master ca799e9: [truetype] Integer overflow.

[Werner LEMBERG]

branch: master
commit ca799e9be52526739691f120285a27b91fd15d68
Author: Werner Lemberg <address@hidden>
Commit: Werner Lemberg <address@hidden>

    [truetype] Integer overflow.
    
    Reported as
    
      https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2455
    
    * src/truetype/ttinterp.c (Ins_SCFS): Use SUB_LONG.
---
 ChangeLog               | 10 ++++++++++
 src/truetype/ttinterp.c |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 30cf630..c6e8229 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2017-07-03  Werner Lemberg  <address@hidden>
+
+       [truetype] Integer overflow.
+
+       Reported as
+
+         https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2455
+
+       * src/truetype/ttinterp.c (Ins_SCFS): Use SUB_LONG.
+
 2017-07-01  Alexei Podtelezhnikov  <address@hidden>
 
        * src/sfnt/sfobjs.c (sfnt_load_face): Ignore No_Unicode_Glyph_Name.
diff --git a/src/truetype/ttinterp.c b/src/truetype/ttinterp.c
index 24318bf..f8bf4af 100644
--- a/src/truetype/ttinterp.c
+++ b/src/truetype/ttinterp.c
@@ -4803,7 +4803,7 @@
 
     K = FAST_PROJECT( &exc->zp2.cur[L] );
 
-    exc->func_move( exc, &exc->zp2, L, args[1] - K );
+    exc->func_move( exc, &exc->zp2, L, SUB_LONG( args[1], K ) );
 
     /* UNDOCUMENTED!  The MS rasterizer does that with */
     /* twilight points (confirmed by Greg Hitchcock)   */