fix(ext/websocket): Avoid write deadlock that requires read_frame to complete #18705
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bartlomieju
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Apr 14, 2023
levex
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Apr 18, 2023
…complete (#18705) Fixes #18700 Timeline of the events that lead to the bug. 1. WebSocket handshake complete 2. Server on `read_frame` holding an AsyncRefCell borrow of the WebSocket stream. 3. Client sends a TXT frame after a some time 4. Server recieves the frame and goes back to `read_frame`. 5. After some time, Server starts a `write_frame` but `read_frame` is still holding a borrow! ^--- Locked. read_frame needs to complete so we can resume the write. This commit changes all writes to directly borrow the `fastwebsocket::WebSocket` resource under the assumption that it won't affect ongoing reads.
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Fixes #18700
Timeline of the events that lead to the bug.
read_frameholding an AsyncRefCell borrow of the WebSocket stream.read_frame.write_framebutread_frameis still holding a borrow!^--- Locked. read_frame needs to complete so we can resume the write.
This commit changes all writes to directly borrow the
fastwebsocket::WebSocketresource under the assumption that it won't affect ongoing reads.