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 92718CCA491 for ; Mon, 13 Jun 2022 13:59:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1380320AbiFMN6p (ORCPT ); Mon, 13 Jun 2022 09:58:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1380162AbiFMNxn (ORCPT ); Mon, 13 Jun 2022 09:53:43 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80B6BB7FB; Mon, 13 Jun 2022 04:34:00 -0700 (PDT) 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 1C6396124B; Mon, 13 Jun 2022 11:34:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06A06C34114; Mon, 13 Jun 2022 11:33:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655120039; bh=swWzbn2TpIpi73RFLngVo0lUDHXK3tIvjiipGZ76mpI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bulihAumDrGz1nt1YOF3aZ17Dw8UtvuWytsIalqp9vy6MOGvBJM0tBX7py9q7dRYD orJPLveiFZgtyGnUmFedWcD836/wzCiM98JZHY/Mlo/ZQOlr5Wn+X5NXd3TSD0ewgG NXgaT7zPrunHh85YMIRiTqkoscTfnrT9yDj+aH3g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anton Makarov , Andrea Mayer , David Ahern , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.18 221/339] net: seg6: fix seg6_lookup_any_nexthop() to handle VRFs using flowi_l3mdev Date: Mon, 13 Jun 2022 12:10:46 +0200 Message-Id: <20220613094933.359666192@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094926.497929857@linuxfoundation.org> References: <20220613094926.497929857@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: Andrea Mayer [ Upstream commit a3bd2102e464202b58d57390a538d96f57ffc361 ] Commit 40867d74c374 ("net: Add l3mdev index to flow struct and avoid oif reset for port devices") adds a new entry (flowi_l3mdev) in the common flow struct used for indicating the l3mdev index for later rule and table matching. The l3mdev_update_flow() has been adapted to properly set the flowi_l3mdev based on the flowi_oif/flowi_iif. In fact, when a valid flowi_iif is supplied to the l3mdev_update_flow(), this function can update the flowi_l3mdev entry only if it has not yet been set (i.e., the flowi_l3mdev entry is equal to 0). The SRv6 End.DT6 behavior in VRF mode leverages a VRF device in order to force the routing lookup into the associated routing table. This routing operation is performed by seg6_lookup_any_nextop() preparing a flowi6 data structure used by ip6_route_input_lookup() which, in turn, (indirectly) invokes l3mdev_update_flow(). However, seg6_lookup_any_nexthop() does not initialize the new flowi_l3mdev entry which is filled with random garbage data. This prevents l3mdev_update_flow() from properly updating the flowi_l3mdev with the VRF index, and thus SRv6 End.DT6 (VRF mode)/DT46 behaviors are broken. This patch correctly initializes the flowi6 instance allocated and used by seg6_lookup_any_nexhtop(). Specifically, the entire flowi6 instance is wiped out: in case new entries are added to flowi/flowi6 (as happened with the flowi_l3mdev entry), we should no longer have incorrectly initialized values. As a result of this operation, the value of flowi_l3mdev is also set to 0. The proposed fix can be tested easily. Starting from the commit referenced in the Fixes, selftests [1],[2] indicate that the SRv6 End.DT6 (VRF mode)/DT46 behaviors no longer work correctly. By applying this patch, those behaviors are back to work properly again. [1] - tools/testing/selftests/net/srv6_end_dt46_l3vpn_test.sh [2] - tools/testing/selftests/net/srv6_end_dt6_l3vpn_test.sh Fixes: 40867d74c374 ("net: Add l3mdev index to flow struct and avoid oif reset for port devices") Reported-by: Anton Makarov Signed-off-by: Andrea Mayer Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20220608091917.20345-1-andrea.mayer@uniroma2.it Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv6/seg6_local.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index 9fbe243a0e81..98a34287439c 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -218,6 +218,7 @@ seg6_lookup_any_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr, struct flowi6 fl6; int dev_flags = 0; + memset(&fl6, 0, sizeof(fl6)); fl6.flowi6_iif = skb->dev->ifindex; fl6.daddr = nhaddr ? *nhaddr : hdr->daddr; fl6.saddr = hdr->saddr; -- 2.35.1