Bug 228329 – WebSocket: Safari on iOS 15 beta 3 is sending invalid close frame

• Status: RESOLVED
• Resolution: FIXED
• Component: WebCore Misc.

[Lars Mikkelsen]

Created attachment 434293 [details]
WebSocket close frame with invalid status code

We have a dev-server based on the ws Node library. We've noticed that Safari on iOS 15 beta 3 is causing ws to throw "RangeError: Invalid WebSocket frame: invalid status code 22373" (as reported by other users at https://github.com/websockets/ws/issues/1916). I've tracked this down to Safari sending a WebSocket close frame without a two-byte status code, so the first two bytes of the reason "WebSocket is closed due to suspension." are interpreted as the status code, i.e. 'We' == 0x5765 == 22373. As far as I can tell the message originates at https://trac.webkit.org/browser/webkit/trunk/Source/WebCore/Modules/websockets/WebSocket.cpp#L522. I suspect r270882 surfaced this issue by now closing the WebSocket when WebSocketChannel::fail() is called. I have a hard time following the code from there, but I believe it eventually ends up calling NSURLSessionWebSocketTask::cancelWithCloseCode in https://trac.webkit.org/browser/webkit/trunk/Source/WebKit/NetworkProcess/cocoa/WebSocketTaskCocoa.mm#L152 with a status code.

[Radar WebKit Bug Importer]

<rdar://problem/81169550>

[Alex Christensen]

Created attachment 434377 [details]
Patch

[Alex Christensen]

Created attachment 434386 [details]
Patch

[EWS]

Committed r280385 (240028@main): <https://commits.webkit.org/240028@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 434386 [details].

[Alex Christensen]

Thanks for the report, Lars!

[Lars Mikkelsen]

Thank you for the super quick fix!