From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F18C6C433EF for ; Mon, 4 Oct 2021 13:34:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9AF2611CB for ; Mon, 4 Oct 2021 13:34:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238061AbhJDNgE (ORCPT ); Mon, 4 Oct 2021 09:36:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:48650 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237915AbhJDNd1 (ORCPT ); Mon, 4 Oct 2021 09:33:27 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8B7D461AFB; Mon, 4 Oct 2021 13:15:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1633353312; bh=6LI1YIgDj93n3QpB3bBhQyuMdgSbIaQMZm7vvdiDFWM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1orxzTpad8ZWN843Ak+RT2gOr0TObH6x2Pv6ZtPTR2krdcyRO6VnzRI2K9bRGb1ma uhBl04C8unZoTZ4Y5WiMjf98dO5cm9g6CXI9HiwyUikSMMiE2jfbeHF7pqs7P1yoHu +DHsh8x3iIwhgROuqEumlLRB5N6tmSAAZlkgZuI0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoph Lameter , Jason Gunthorpe , Sasha Levin Subject: [PATCH 5.14 078/172] IB/cma: Do not send IGMP leaves for sendonly Multicast groups Date: Mon, 4 Oct 2021 14:52:08 +0200 Message-Id: <20211004125047.517377919@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211004125044.945314266@linuxfoundation.org> References: <20211004125044.945314266@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christoph Lameter [ Upstream commit 2cc74e1ee31d00393b6698ec80b322fd26523da4 ] ROCE uses IGMP for Multicast instead of the native Infiniband system where joins are required in order to post messages on the Multicast group. On Ethernet one can send Multicast messages to arbitrary addresses without the need to subscribe to a group. So ROCE correctly does not send IGMP joins during rdma_join_multicast(). F.e. in cma_iboe_join_multicast() we see: if (addr->sa_family == AF_INET) { if (gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP) { ib.rec.hop_limit = IPV6_DEFAULT_HOPLIMIT; if (!send_only) { err = cma_igmp_send(ndev, &ib.rec.mgid, true); } } } else { So the IGMP join is suppressed as it is unnecessary. However no such check is done in destroy_mc(). And therefore leaving a sendonly multicast group will send an IGMP leave. This means that the following scenario can lead to a multicast receiver unexpectedly being unsubscribed from a MC group: 1. Sender thread does a sendonly join on MC group X. No IGMP join is sent. 2. Receiver thread does a regular join on the same MC Group x. IGMP join is sent and the receiver begins to get messages. 3. Sender thread terminates and destroys MC group X. IGMP leave is sent and the receiver no longer receives data. This patch adds the same logic for sendonly joins to destroy_mc() that is also used in cma_iboe_join_multicast(). Fixes: ab15c95a17b3 ("IB/core: Support for CMA multicast join flags") Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2109081340540.668072@gentwo.de Signed-off-by: Christoph Lameter Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/core/cma.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index 36ab9da70932..107462905b21 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -1818,6 +1818,8 @@ static void cma_release_port(struct rdma_id_private *id_priv) static void destroy_mc(struct rdma_id_private *id_priv, struct cma_multicast *mc) { + bool send_only = mc->join_state == BIT(SENDONLY_FULLMEMBER_JOIN); + if (rdma_cap_ib_mcast(id_priv->id.device, id_priv->id.port_num)) ib_sa_free_multicast(mc->sa_mc); @@ -1834,7 +1836,10 @@ static void destroy_mc(struct rdma_id_private *id_priv, cma_set_mgid(id_priv, (struct sockaddr *)&mc->addr, &mgid); - cma_igmp_send(ndev, &mgid, false); + + if (!send_only) + cma_igmp_send(ndev, &mgid, false); + dev_put(ndev); } -- 2.33.0