Add image usability checks to drawImage()

1 files changed, 8 insertions, 0 deletions

diff --git a/components/script/canvas_state.rs b/components/script/canvas_state.rs
index c9492ed5da5..ebf36bad32b 100644
--- a/components/script/canvas_state.rs
+++ b/components/script/canvas_state.rs
@@ -388,6 +388,14 @@ impl CanvasState {
                 self.draw_offscreen_canvas(&canvas, htmlcanvas, sx, sy, sw, sh, dx, dy, dw, dh)
             },
             CanvasImageSource::HTMLImageElement(ref image) => {
+                // https://html.spec.whatwg.org/multipage/#drawing-images
+                // 2. Let usability be the result of checking the usability of image.
+                // 3. If usability is bad, then return (without drawing anything).
+                if !image.is_usable()? {
+                    return Ok(());
+                }
+
+                // TODO(pylbrecht): is it possible for image.get_url() to return None after the usability check?
                 // https://html.spec.whatwg.org/multipage/#img-error
                 // If the image argument is an HTMLImageElement object that is in the broken state,
                 // then throw an InvalidStateError exception