1 files changed, 8 insertions, 0 deletions
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 059c6941bc1..b09d768fea0 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -1481,6 +1481,10 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.4
     fn Scissor(&self, x: i32, y: i32, width: i32, height: i32) {
+        if width < 0 || height < 0 {
+            return self.webgl_error(InvalidValue)
+        }
+
         self.ipc_renderer
             .send(CanvasMsg::WebGL(WebGLCommand::Scissor(x, y, width, height)))
             .unwrap()
@@ -1893,6 +1897,10 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.4
     fn Viewport(&self, x: i32, y: i32, width: i32, height: i32) {
+        if width < 0 || height < 0 {
+            return self.webgl_error(InvalidValue)
+        }
+
         self.ipc_renderer
             .send(CanvasMsg::WebGL(WebGLCommand::Viewport(x, y, width, height)))
             .unwrap()