websocket: free the Redis context on close instead of disconnecting - #271
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SAY-5 wants to merge 1 commit into
Open
websocket: free the Redis context on close instead of disconnecting#271SAY-5 wants to merge 1 commit into
SAY-5 wants to merge 1 commit into
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Signed-off-by: Sai Asish Y <say.apm35@gmail.com>
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ws_client_free() calls redisAsyncDisconnect() and then frees ws->cmd, but hiredis defers the disconnect while replies are still pending. When a WebSocket client goes away in the middle of a blocking command (BLPOP, XREADGROUP BLOCK), the reply arrives later and json_reply() runs with the freed cmd as privdata, which is the memmove crash in #270. Using redisAsyncFree() runs the pending callbacks with a NULL reply right away, while ws and cmd are still valid and close_after_events already stops anything from being written.
I could not add an automated test for this since it needs a real Redis with a blocked client; the sequence in the issue (connect via WS, send BLPOP, disconnect, let the timeout expire) is what triggers it.
Fixes #270