Auto merge of #13060 - anholt:webgl-invalid-passed-params, r=emilio

webgl: Do validation of glScissor/glViewport(width, height) on the DOM side

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webgl: Do validation of glScissor/glViewport(width, height) on the DOM side

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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Avoids testcase CRASHes due to unexpected GL errors.

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1 files changed, 8 insertions, 0 deletions

diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 7814296c38a..d20e55429c4 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -1526,6 +1526,10 @@ 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()
@@ -1938,6 +1942,10 @@ 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()