Fix CVE-2016-9297:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-9297
http://bugzilla.maptools.org/show_bug.cgi?id=2590

Patch copied from upstream source repository.

2016-11-11 Even Rouault <even.rouault at spatialys.com>

        * libtiff/tif_dirread.c: in TIFFFetchNormalTag(), make sure that
        values of tags with TIFF_SETGET_C16_ASCII / TIFF_SETGET_C32_ASCII
        access are null terminated, to avoid potential read outside buffer
        in _TIFFPrintField().
        Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2590


/cvs/maptools/cvsroot/libtiff/ChangeLog,v  <--  ChangeLog
new revision: 1.1154; previous revision: 1.1153
/cvs/maptools/cvsroot/libtiff/libtiff/tif_dirread.c,v  <-- 
libtiff/tif_dirread.c
new revision: 1.203; previous revision: 1.202Index: libtiff/libtiff/tif_dirread.c
===================================================================
RCS file: /cvs/maptools/cvsroot/libtiff/libtiff/tif_dirread.c,v
retrieving revision 1.202
retrieving revision 1.203
diff -u -r1.202 -r1.203
--- libtiff/libtiff/tif_dirread.c	11 Nov 2016 20:01:55 -0000	1.202
+++ libtiff/libtiff/tif_dirread.c	11 Nov 2016 20:22:01 -0000	1.203
@@ -5000,6 +5000,11 @@
 					if (err==TIFFReadDirEntryErrOk)
 					{
 						int m;
+                        if( data[dp->tdir_count-1] != '\0' )
+                        {
+                            TIFFWarningExt(tif->tif_clientdata,module,"ASCII value for tag \"%s\" does not end in null byte. Forcing it to be null",fip->field_name);
+                            data[dp->tdir_count-1] = '\0';
+                        }
 						m=TIFFSetField(tif,dp->tdir_tag,(uint16)(dp->tdir_count),data);
 						if (data!=0)
 							_TIFFfree(data);
@@ -5172,6 +5177,11 @@
 				if (err==TIFFReadDirEntryErrOk)
 				{
 					int m;
+                    if( data[dp->tdir_count-1] != '\0' )
+                    {
+                        TIFFWarningExt(tif->tif_clientdata,module,"ASCII value for tag \"%s\" does not end in null byte. Forcing it to be null",fip->field_name);
+                        data[dp->tdir_count-1] = '\0';
+                    }
 					m=TIFFSetField(tif,dp->tdir_tag,(uint32)(dp->tdir_count),data);
 					if (data!=0)
 						_TIFFfree(data);