[sfnt] Fix Savannah bug #43656.

* src/sfnt/ttcmap.c (tt_cmap4_validate): Fix order of validity
tests.

ChangeLog

@@ -1,3 +1,10 @@
+2014-11-22  Werner Lemberg  <wl@gnu.org>
+
+	[sfnt] Fix Savannah bug #43656.
+
+	* src/sfnt/ttcmap.c (tt_cmap4_validate): Fix order of validity
+	tests.
+
 2014-11-21  Werner Lemberg  <wl@gnu.org>
 
 	[type1, type42] Fix Savannah bug #43655.

src/sfnt/ttcmap.c

@@ -845,9 +845,6 @@
     p      = table + 2;           /* skip format */
     length = TT_NEXT_USHORT( p );
 
-    if ( length < 16 )
-      FT_INVALID_TOO_SHORT;
-
     /* in certain fonts, the `length' field is invalid and goes */
     /* out of bound.  We try to correct this here...            */
     if ( table + length > valid->limit )
@@ -858,6 +855,9 @@
       length = (FT_UInt)( valid->limit - table );
     }
 
+    if ( length < 16 )
+      FT_INVALID_TOO_SHORT;
+
     p        = table + 6;
     num_segs = TT_NEXT_USHORT( p );   /* read segCountX2 */