From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF1628F57 for ; Mon, 13 Feb 2023 14:55:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 64078C433EF; Mon, 13 Feb 2023 14:55:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1676300155; bh=lkjKwDHTAZ1VYrN43NqHOcIg11AWeH4x+eAm1PuIb1g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RVjkZZZkGHNZYxxt0WxD9bNAQiEfPLDTb3tYO3H/uGxmWIQxmC9dLbN+aG6AfsAXH zJ+wmBUOgXDO5J8WIKnz4UlXAUH4K7nBhXqWArXxK7H2OUfg0Sunpc1jImIuCbuY38 ERCfk09Mi7xM/rVFUYoLgb1ZIVN4bc1zeg4ncCOw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Paolo Abeni , Matthieu Baerts , "David S. Miller" Subject: [PATCH 6.1 079/114] mptcp: do not wait for bare sockets timeout Date: Mon, 13 Feb 2023 15:48:34 +0100 Message-Id: <20230213144746.251373216@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230213144742.219399167@linuxfoundation.org> References: <20230213144742.219399167@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Paolo Abeni commit d4e85922e3e7ef2071f91f65e61629b60f3a9cf4 upstream. If the peer closes all the existing subflows for a given mptcp socket and later the application closes it, the current implementation let it survive until the timewait timeout expires. While the above is allowed by the protocol specification it consumes resources for almost no reason and additionally causes sporadic self-tests failures. Let's move the mptcp socket to the TCP_CLOSE state when there are no alive subflows at close time, so that the allocated resources will be freed immediately. Fixes: e16163b6e2b7 ("mptcp: refactor shutdown and close") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni Reviewed-by: Matthieu Baerts Signed-off-by: Matthieu Baerts Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/mptcp/protocol.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2908,6 +2908,7 @@ bool __mptcp_close(struct sock *sk, long struct mptcp_subflow_context *subflow; struct mptcp_sock *msk = mptcp_sk(sk); bool do_cancel_work = false; + int subflows_alive = 0; sk->sk_shutdown = SHUTDOWN_MASK; @@ -2933,6 +2934,8 @@ cleanup: struct sock *ssk = mptcp_subflow_tcp_sock(subflow); bool slow = lock_sock_fast_nested(ssk); + subflows_alive += ssk->sk_state != TCP_CLOSE; + /* since the close timeout takes precedence on the fail one, * cancel the latter */ @@ -2948,6 +2951,12 @@ cleanup: } sock_orphan(sk); + /* all the subflows are closed, only timeout can change the msk + * state, let's not keep resources busy for no reasons + */ + if (subflows_alive == 0) + inet_sk_state_store(sk, TCP_CLOSE); + sock_hold(sk); pr_debug("msk=%p state=%d", sk, sk->sk_state); if (mptcp_sk(sk)->token)