Auto merge of #20699 - simartin:issue_20593, r=nox

Issue #20593: Implement proper checks in WebGLRenderingContext's getFramebufferAttachmentParameter().

Add missing input checks.

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach build-geckolib` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #20593
- [X] There are tests for these changes

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1 files changed, 30 insertions, 1 deletions

diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 7beeef9261d..60474753eb3 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -2379,7 +2379,36 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             _ => false
         };
 
-        if !target_matches || !attachment_matches || !pname_matches {
+        let bound_attachment_matches = match self.bound_framebuffer.get().unwrap().attachment(attachment) {
+            Some(attachment_root) => {
+                match attachment_root {
+                    WebGLFramebufferAttachmentRoot::Renderbuffer(_) => {
+                        match pname {
+                            constants::FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE |
+                            constants::FRAMEBUFFER_ATTACHMENT_OBJECT_NAME => true,
+                            _ => false
+                        }
+                    },
+                    WebGLFramebufferAttachmentRoot::Texture(_) => {
+                        match pname {
+                            constants::FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE |
+                            constants::FRAMEBUFFER_ATTACHMENT_OBJECT_NAME |
+                            constants::FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL |
+                            constants::FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE => true,
+                            _ => false
+                        }
+                    }
+                }
+            },
+            _ => {
+                match pname {
+                    constants::FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE => true,
+                    _ => false
+                }
+            }
+        };
+
+        if !target_matches || !attachment_matches || !pname_matches || !bound_attachment_matches {
             self.webgl_error(InvalidEnum);
             return NullValue();
         }