perf script: Add array bound checking to list_scripts

Don't overflow array when the scripts directory is too large, or the
script file name is too long.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20190311144502.15423-11-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/scripts.c

@@ -97,7 +97,8 @@ static int list_scripts(char *script_name, bool *custom,
 		paths[i] = names[i] + SCRIPT_NAMELEN;
 	}
 
-	num = find_scripts(names + max_std, paths + max_std);
+	num = find_scripts(names + max_std, paths + max_std, SCRIPT_MAX_NO - max_std,
+			SCRIPT_FULLPATH_LEN);
 	if (num < 0)
 		num = 0;
 	choice = ui__popup_menu(num + max_std, (char * const *)names);