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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 145C3C54EBE for ; Mon, 16 Jan 2023 16:06:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232259AbjAPQGM (ORCPT ); Mon, 16 Jan 2023 11:06:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43880 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232064AbjAPQFp (ORCPT ); Mon, 16 Jan 2023 11:05:45 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14EAF274AD for ; Mon, 16 Jan 2023 08:04:03 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8DA6061049 for ; Mon, 16 Jan 2023 16:04:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C67AC433D2; Mon, 16 Jan 2023 16:04:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673885042; bh=wDgTdSDYDoEr4cSxVZpF4BI8puZycLQrplwYdLz8DeI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CTD0fbyyIanNDE0RMoSDITXtYe63NKVY9g0gq0XMnHC0llpiF+VX0fDIH16iCLSzk cGisng5YkYYT4u8PSr8I/V0spOIDF59CydsfA4zB2CW8v69HfwakXMqqs2SUnsKUHt 7O5Fhryryh1V3H2Rq3TXPEdNAUrwX3GXEH230wg8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jon Maloy , Tung Nguyen , "David S. Miller" , Sasha Levin Subject: [PATCH 5.15 52/86] tipc: fix unexpected link reset due to discovery messages Date: Mon, 16 Jan 2023 16:51:26 +0100 Message-Id: <20230116154749.224093584@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154747.036911298@linuxfoundation.org> References: <20230116154747.036911298@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Tung Nguyen [ Upstream commit c244c092f1ed2acfb5af3d3da81e22367d3dd733 ] This unexpected behavior is observed: node 1 | node 2 ------ | ------ link is established | link is established reboot | link is reset up | send discovery message receive discovery message | link is established | link is established send discovery message | | receive discovery message | link is reset (unexpected) | send reset message link is reset | It is due to delayed re-discovery as described in function tipc_node_check_dest(): "this link endpoint has already reset and re-established contact with the peer, before receiving a discovery message from that node." However, commit 598411d70f85 has changed the condition for calling tipc_node_link_down() which was the acceptance of new media address. This commit fixes this by restoring the old and correct behavior. Fixes: 598411d70f85 ("tipc: make resetting of links non-atomic") Acked-by: Jon Maloy Signed-off-by: Tung Nguyen Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/tipc/node.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/tipc/node.c b/net/tipc/node.c index 49ddc484c4fe..5e000fde8067 100644 --- a/net/tipc/node.c +++ b/net/tipc/node.c @@ -1179,8 +1179,9 @@ void tipc_node_check_dest(struct net *net, u32 addr, bool addr_match = false; bool sign_match = false; bool link_up = false; + bool link_is_reset = false; bool accept_addr = false; - bool reset = true; + bool reset = false; char *if_name; unsigned long intv; u16 session; @@ -1200,14 +1201,14 @@ void tipc_node_check_dest(struct net *net, u32 addr, /* Prepare to validate requesting node's signature and media address */ l = le->link; link_up = l && tipc_link_is_up(l); + link_is_reset = l && tipc_link_is_reset(l); addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr)); sign_match = (signature == n->signature); /* These three flags give us eight permutations: */ if (sign_match && addr_match && link_up) { - /* All is fine. Do nothing. */ - reset = false; + /* All is fine. Ignore requests. */ /* Peer node is not a container/local namespace */ if (!n->peer_hash_mix) n->peer_hash_mix = hash_mixes; @@ -1232,6 +1233,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, */ accept_addr = true; *respond = true; + reset = true; } else if (!sign_match && addr_match && link_up) { /* Peer node rebooted. Two possibilities: * - Delayed re-discovery; this link endpoint has already @@ -1263,6 +1265,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, n->signature = signature; accept_addr = true; *respond = true; + reset = true; } if (!accept_addr) @@ -1291,6 +1294,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, tipc_link_fsm_evt(l, LINK_RESET_EVT); if (n->state == NODE_FAILINGOVER) tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT); + link_is_reset = tipc_link_is_reset(l); le->link = l; n->link_cnt++; tipc_node_calculate_timer(n, l); @@ -1303,7 +1307,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, memcpy(&le->maddr, maddr, sizeof(*maddr)); exit: tipc_node_write_unlock(n); - if (reset && l && !tipc_link_is_reset(l)) + if (reset && !link_is_reset) tipc_node_link_down(n, b->identity, false); tipc_node_put(n); } -- 2.35.1