From patchwork Mon Jun 1 17:54:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 225068 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 888AAC433DF for ; Mon, 1 Jun 2020 18:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 660902077D for ; Mon, 1 Jun 2020 18:11:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035068; bh=/ueERacqKCvBCeDX7uFQVBAHO7WaNeHHjAAedKNnKy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=o+2oSElizarZsI9n3pBv+Nkg+xl77Z8L7iR49kqTUfEKAsMno1kB+3Edjy8BipRb+ DMCeBPHFr8LuaFBX/dd3vZl6RpeDoADd0Ge9BlWjETz/B3daC2b7ThqZvpH5FQ1FPG CDhzLP++ugm2WAI29Il0skyfdKLsuIUNkopgS0AA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731066AbgFASLE (ORCPT ); Mon, 1 Jun 2020 14:11:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:58112 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730157AbgFASLD (ORCPT ); Mon, 1 Jun 2020 14:11:03 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F01872065C; Mon, 1 Jun 2020 18:11:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035062; bh=/ueERacqKCvBCeDX7uFQVBAHO7WaNeHHjAAedKNnKy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NHfp623QL68eCP9ZvpVcRmERESZnIj+En0Z/SmfaLme8udD8q9+tq4s1EqsdN1qS0 ENSklH2IdBw1LUoe7eNP9xnNr3ycS0Ca7PWp7ixHpwB20j3Ig3lCvrBky9hy3icBIn nmaCBtuyVqzxqyuUXlxgiubF9XtGaxbWkx9rBMTc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Ahern , Nikolay Aleksandrov , "David S. Miller" Subject: [PATCH 5.4 134/142] nexthop: Expand nexthop_is_multipath in a few places Date: Mon, 1 Jun 2020 19:54:52 +0200 Message-Id: <20200601174051.606199324@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174037.904070960@linuxfoundation.org> References: <20200601174037.904070960@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: David Ahern commit 0b5e2e39739e861fa5fc84ab27a35dbe62a15330 upstream. I got too fancy consolidating checks on multipath type. The result is that path lookups can access 2 different nh_grp structs as exposed by Nik's torture tests. Expand nexthop_is_multipath within nexthop.h to avoid multiple, nh_grp dereferences and make decisions based on the consistent struct. Only 2 places left using nexthop_is_multipath are within IPv6, both only check that the nexthop is a multipath for a branching decision which are acceptable. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: David Ahern Acked-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/nexthop.h | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-) --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -137,21 +137,20 @@ static inline unsigned int nexthop_num_p { unsigned int rc = 1; - if (nexthop_is_multipath(nh)) { + if (nh->is_group) { struct nh_group *nh_grp; nh_grp = rcu_dereference_rtnl(nh->nh_grp); - rc = nh_grp->num_nh; + if (nh_grp->mpath) + rc = nh_grp->num_nh; } return rc; } static inline -struct nexthop *nexthop_mpath_select(const struct nexthop *nh, int nhsel) +struct nexthop *nexthop_mpath_select(const struct nh_group *nhg, int nhsel) { - const struct nh_group *nhg = rcu_dereference_rtnl(nh->nh_grp); - /* for_nexthops macros in fib_semantics.c grabs a pointer to * the nexthop before checking nhsel */ @@ -186,12 +185,14 @@ static inline bool nexthop_is_blackhole( { const struct nh_info *nhi; - if (nexthop_is_multipath(nh)) { - if (nexthop_num_path(nh) > 1) - return false; - nh = nexthop_mpath_select(nh, 0); - if (!nh) + if (nh->is_group) { + struct nh_group *nh_grp; + + nh_grp = rcu_dereference_rtnl(nh->nh_grp); + if (nh_grp->num_nh > 1) return false; + + nh = nh_grp->nh_entries[0].nh; } nhi = rcu_dereference_rtnl(nh->nh_info); @@ -217,10 +218,15 @@ struct fib_nh_common *nexthop_fib_nhc(st BUILD_BUG_ON(offsetof(struct fib_nh, nh_common) != 0); BUILD_BUG_ON(offsetof(struct fib6_nh, nh_common) != 0); - if (nexthop_is_multipath(nh)) { - nh = nexthop_mpath_select(nh, nhsel); - if (!nh) - return NULL; + if (nh->is_group) { + struct nh_group *nh_grp; + + nh_grp = rcu_dereference_rtnl(nh->nh_grp); + if (nh_grp->mpath) { + nh = nexthop_mpath_select(nh_grp, nhsel); + if (!nh) + return NULL; + } } nhi = rcu_dereference_rtnl(nh->nh_info); @@ -264,8 +270,11 @@ static inline struct fib6_nh *nexthop_fi { struct nh_info *nhi; - if (nexthop_is_multipath(nh)) { - nh = nexthop_mpath_select(nh, 0); + if (nh->is_group) { + struct nh_group *nh_grp; + + nh_grp = rcu_dereference_rtnl(nh->nh_grp); + nh = nexthop_mpath_select(nh_grp, 0); if (!nh) return NULL; }