Index: gif2tiff.c
===================================================================
RCS file: /cvs/maptools/cvsroot/libtiff/tools/gif2tiff.c,v
retrieving revision 1.12
diff -u -r1.12 gif2tiff.c
--- gif2tiff.c	15 Dec 2010 00:22:44 -0000	1.12
+++ gif2tiff.c	13 Aug 2013 08:25:38 -0000
@@ -333,6 +333,10 @@
     int status = 1;
 
     datasize = getc(infile);
+
+    if (datasize > 12)
+        return 0;
+
     clear = 1 << datasize;
     eoi = clear + 1;
     avail = clear + 2;