[cff] Integer overflow.

Reported as https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2109 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2110 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2122 * src/cff/cf2blues.c (cf2_blues_init): Use OVERFLOW_SUB_INT32. * src/cff/cf2hints.c (cf2_hintmap_map): Synchronize if-else branches.
8 years ago · 24848a3d58
parent 8667042997
commit 24848a3d58
3 changed files with 20 additions and 3 deletions
--- a/15
+++ b/15
@ -1,3 +1,18 @@
+2017-06-06  Werner Lemberg  <wl@gnu.org>
+
+	[cff] Integer overflow.
+
+	Reported as
+
+	  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2109
+	  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2110
+	  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2122
+
+	* src/cff/cf2blues.c (cf2_blues_init): Use OVERFLOW_SUB_INT32.
+
+	* src/cff/cf2hints.c (cf2_hintmap_map): Synchronize if-else
+	branches.
+
 2017-06-05  Werner Lemberg  <wl@gnu.org>

 	[cff] Integer overflow.
--- a/src/cff/cf2blues.c
+++ b/src/cff/cf2blues.c
@ -194,8 +194,9 @@
      blues->zone[blues->count].csTopEdge =
        cf2_blueToFixed( blueValues[i + 1] );

-      zoneHeight = blues->zone[blues->count].csTopEdge -
-                   blues->zone[blues->count].csBottomEdge;
+      zoneHeight = OVERFLOW_SUB_INT32(
+                     blues->zone[blues->count].csTopEdge,
+                     blues->zone[blues->count].csBottomEdge );

      if ( zoneHeight < 0 )
      {
--- a/src/cff/cf2hints.c
+++ b/src/cff/cf2hints.c
@ -332,7 +332,8 @@
      {
        /* special case for points below first edge: use uniform scale */
        return OVERFLOW_ADD_INT32(
-                 FT_MulFix( csCoord - hintmap->edge[0].csCoord,
+                 FT_MulFix( OVERFLOW_SUB_INT32( csCoord,
+                                                hintmap->edge[0].csCoord ),
                            hintmap->scale ),
                 hintmap->edge[0].dsCoord );
      }