[freetype2] master 827ca3b: [truetype] Integer overflow issues.

[Werner LEMBERG]

branch: master
commit 827ca3bcf25b9e4dc2edf31381c0774e1d227285
Author: Werner Lemberg <address@hidden>
Commit: Werner Lemberg <address@hidden>

    [truetype] Integer overflow issues.
    
    Reported as
    
      https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=7652
    
    * src/truetype/ttinterp.c (Ins_MDAP): Use SUB_LONG.
---
 ChangeLog               | 10 ++++++++++
 src/truetype/ttinterp.c | 18 ++++++++++--------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1a338bb..b929801 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2018-04-14  Werner Lemberg  <address@hidden>
 
+       [truetype] Integer overflow issues.
+
+       Reported as
+
+         https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=7652
+
+       * src/truetype/ttinterp.c (Ins_MDAP): Use SUB_LONG.
+
+2018-04-14  Werner Lemberg  <address@hidden>
+
        [autofit] Update to Unicode 11.0.0.
 
        But no support new scripts (volunteers welcomed).
diff --git a/src/truetype/ttinterp.c b/src/truetype/ttinterp.c
index 6a5b823..d9865d4 100644
--- a/src/truetype/ttinterp.c
+++ b/src/truetype/ttinterp.c
@@ -5874,16 +5874,18 @@
       if ( SUBPIXEL_HINTING_INFINALITY &&
            exc->ignore_x_mode          &&
            exc->GS.freeVector.x != 0   )
-        distance = Round_None(
-                     exc,
-                     cur_dist,
-                     exc->tt_metrics.compensations[0] ) - cur_dist;
+        distance = SUB_LONG(
+                     Round_None( exc,
+                                 cur_dist,
+                                 exc->tt_metrics.compensations[0] ),
+                     cur_dist );
       else
 #endif
-        distance = exc->func_round(
-                     exc,
-                     cur_dist,
-                     exc->tt_metrics.compensations[0] ) - cur_dist;
+        distance = SUB_LONG(
+                     exc->func_round( exc,
+                                      cur_dist,
+                                      exc->tt_metrics.compensations[0] ),
+                     cur_dist );
     }
     else
       distance = 0;