From 29f641951be0d91036d77edf677807f1447dbe65 Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" Date: Tue, 8 Sep 2026 16:07:07 +0200 Subject: [PATCH] mptcp: subflow: no need to copy thmac during ulp_clone 'thmac' is not used after that point. Indeed, subflow_ulp_clone() is called when the request on the passive side is over, so when the truncated HMAC is no longer needed. Note that in case of SYN cookies, thmac will not be initialised. So better to remove it to avoid a warning from debug tools like KMSAN for reading uninitialised data. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Cc: stable@vger.kernel.org Reviewed-by: Geliang Tang Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260908-net-mptcp-misc-fixes-7-3-rc1-v2-2-df1de70348b6@kernel.org Signed-off-by: Jakub Kicinski --- net/mptcp/subflow.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index af81ad5e699d..01db7edce18a 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -2084,7 +2084,6 @@ static void subflow_ulp_clone(const struct request_sock *req, new_ctx->request_bkup = subflow_req->request_bkup; WRITE_ONCE(new_ctx->remote_id, subflow_req->remote_id); new_ctx->token = subflow_req->token; - new_ctx->thmac = subflow_req->thmac; /* the subflow req id is valid, fetched via subflow_check_req() * and subflow_token_join_request()