Bug 107389 – <script crossorigin> not handled correctly when server doesn't send the right headers

• Status: NEW
• Component: DOM

[Boris Zbarsky]

Accordiing to https://bugzilla.mozilla.org/show_bug.cgi?id=832587#c0 a <script crossorigin> with a cross-origin URL to a server that's not sending the right access-control-allow-origin headers executes in Chrome.  That's not what the spec says to do.  In particular, see http://www.whatwg.org/specs/web-apps/current-work/multipage/fetching-resources.html#potentially-cors-enabled-fetch the part about 'If mode is "Anonymous" or "Use Credentials"' under 'If the CORS cross-origin request status is not success'.

[Pablo Flouret]

Do you have a testcase that i can look at?

Otherwise, if i understand you correctly, this test does what you mean, no? http://trac.webkit.org/browser/trunk/LayoutTests/http/tests/security/script-with-failed-cors-check-fails-to-load.html

[Pablo Flouret]

Ah, i see the testcase in the bugzilla bug, looking at it now.

[Pablo Flouret]

I wasn't aware that when the parser triggers the script request it follows a different code path that doesn't end up in ScriptElement::notifyFinished() so the check is never done.

I'm not super familiar with how the parser does things, is HTMLScriptRunner::executePendingScriptAndDispatchEvent() the right place to do the CORS check (or HTMLScriptRunner::runScript(), or both)?