[PATCH] Fix stack buffer overflow in GTIFGetProj4Defn()

[rouault]

A stack buffer overflow can occur if psDefn->UOMLengthInMeters has a big non fractionnal part (for example 123456789.12345678).

Patch :

Index: frmts/gtiff/libgeotiff/geotiff_proj4.c
===================================================================
--- frmts/gtiff/libgeotiff/geotiff_proj4.c	(révision 15995)
+++ frmts/gtiff/libgeotiff/geotiff_proj4.c	(copie de travail)
@@ -161,7 +161,8 @@
     }
     else
     {
-        sprintf( szUnits, "+to_meter=%.10f", psDefn->UOMLengthInMeters );
+        snprintf( szUnits, sizeof(szUnits), "+to_meter=%.10f", psDefn->UOMLengthInMeters );
+        szUnits[sizeof(szUnits)-1] = '\0';
     }
 
 /* -------------------------------------------------------------------- */

[warmerdam]

The sprintf() page suggests it is a C99 function and I'm hesitant to depend on C99 functions in libgeotiff. Instead I have just increased the size of szUnits (r1502) even though it is not a proper solution of the problem.