Don't open the tz file if we're running setuid or setgid to prevent infomration

leakage.

Submitted by:	Julian Assange

lib/libc/stdtime/localtime.c

@@ -305,7 +305,9 @@ register struct state * const	sp;
 				doaccess = TRUE;
 			name = fullname;
 		}
-		if (doaccess && access(name, R_OK) != 0)
+		/* XXX Should really be issetguid(), but we don't have that */
+		if (doaccess && 
+			(getuid() != geteuid() || getgid() != getegid()) )
 		     	return -1;
 		if ((fid = open(name, OPEN_MODE)) == -1)
 			return -1;