[gnome-shell/gnome-3-10] screenshot: Extend ScreenshotArea parameter validation

[Florian Müllner <fmuellner src gnome org>]

commit 3ac7bf874c1983e6f268235114c75832eb1d807b
Author: Florian Müllner <fmuellner gnome org>
Date:   Mon Nov 4 11:14:44 2013 +0100

    screenshot: Extend ScreenshotArea parameter validation
    
    We currently only ensure that width and height are positive, so it
    is still possible to pass in values that don't make any sense at all
    (which may even result in a crash when exceeding limits imposed by
    X11).
    There is nothing to screenshot outside the actual screen area, so
    restrict the parameters to that.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=699752

 js/ui/screenshot.js |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/js/ui/screenshot.js b/js/ui/screenshot.js
index 92efd03..bbeddd0 100644
--- a/js/ui/screenshot.js
+++ b/js/ui/screenshot.js
@@ -77,7 +77,9 @@ const ScreenshotService = new Lang.Class({
 
     ScreenshotAreaAsync : function (params, invocation) {
         let [x, y, width, height, flash, filename, callback] = params;
-        if (height <= 0 || width <= 0) {
+        if (x < 0 || y < 0 ||
+            width <= 0 || height <= 0 ||
+            x + width > global.screen_width || y + height > global.screen_height) {
             invocation.return_error_literal(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED,
                         "Invalid params");
             return;