From patchwork Thu Nov 5 20:21:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Saeed Mahameed X-Patchwork-Id: 1395257 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=nvidia.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=nvidia.com header.i=@nvidia.com header.a=rsa-sha256 header.s=n1 header.b=Wcir2ibJ; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CRw1375DJz9sVL for ; Fri, 6 Nov 2020 07:22:15 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732519AbgKEUWO (ORCPT ); Thu, 5 Nov 2020 15:22:14 -0500 Received: from hqnvemgate24.nvidia.com ([216.228.121.143]:6729 "EHLO hqnvemgate24.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732325AbgKEUWM (ORCPT ); Thu, 5 Nov 2020 15:22:12 -0500 Received: from hqmail.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate24.nvidia.com (using TLS: TLSv1.2, AES256-SHA) id ; Thu, 05 Nov 2020 12:22:13 -0800 Received: from sx1.mtl.com (10.124.1.5) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 5 Nov 2020 20:22:11 +0000 From: Saeed Mahameed To: Jakub Kicinski CC: , "David S. Miller" , "Vlad Buslov" , Roi Dayan , Saeed Mahameed Subject: [net v2 2/7] net/mlx5e: Protect encap route dev from concurrent release Date: Thu, 5 Nov 2020 12:21:24 -0800 Message-ID: <20201105202129.23644-3-saeedm@nvidia.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201105202129.23644-1-saeedm@nvidia.com> References: <20201105202129.23644-1-saeedm@nvidia.com> MIME-Version: 1.0 X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL111.nvidia.com (172.20.187.18) To HQMAIL107.nvidia.com (172.20.187.13) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1604607733; bh=6mOu6eo+I0YHui4C0Rq7XRcO61Y6ppeSKI1OWyTsAwg=; h=From:To:CC:Subject:Date:Message-ID:X-Mailer:In-Reply-To: References:MIME-Version:Content-Transfer-Encoding:Content-Type: X-Originating-IP:X-ClientProxiedBy; b=Wcir2ibJ+28toUKQ1J3YFRzhIJvFqz63Fa6gyvurlIatWZoUFJhgxBT8+AHxZops4 bb68Gs/A4JpAAPDf7aACJNNmwkbUiYtbKV7A7lMhdw/8WerXPGds9MIMxVaMmnJJRt lU/IKdNwh5Z5Uqdbv3NY+pww5APjb25ueLyr57aBCREb05LHhC74ieZ0L+qE2F9ucI Yaozco7CNkRude34CpGYcovDN7yBTOVZRWzzK2IAZhAuwNiAA4yIb5TKpz0TdD3mcb wC9gPjhe65UOJ5xi3m3Kjl81eyTiTaV6o51RTaNyJJObhNbZKg3VXexX9Ofx1OjMvI x7AatuOf/fgSg== Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vlad Buslov In functions mlx5e_route_lookup_ipv{4|6}() route_dev can be arbitrary net device and not necessary mlx5 eswitch port representor. As such, in order to ensure that route_dev is not destroyed concurrent the code needs either explicitly take reference to the device before releasing reference to rtable instance or ensure that caller holds rtnl lock. First approach is chosen as a fix since rtnl lock dependency was intentionally removed from mlx5 TC layer. To prevent unprotected usage of route_dev in encap code take a reference to the device before releasing rt. Don't save direct pointer to the device in mlx5_encap_entry structure and use ifindex instead. Modify users of route_dev pointer to properly obtain the net device instance from its ifindex. Fixes: 61086f391044 ("net/mlx5e: Protect encap hash table with mutex") Fixes: 6707f74be862 ("net/mlx5e: Update hw flows when encap source mac changed") Signed-off-by: Vlad Buslov Reviewed-by: Roi Dayan Signed-off-by: Saeed Mahameed --- .../ethernet/mellanox/mlx5/core/en/rep/tc.c | 6 +- .../ethernet/mellanox/mlx5/core/en/tc_tun.c | 72 ++++++++++++------- .../net/ethernet/mellanox/mlx5/core/en_rep.h | 2 +- 3 files changed, 52 insertions(+), 28 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c index e36e505d38ad..d29af7b9c695 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c @@ -107,12 +107,16 @@ void mlx5e_rep_update_flows(struct mlx5e_priv *priv, mlx5e_tc_encap_flows_del(priv, e, &flow_list); if (neigh_connected && !(e->flags & MLX5_ENCAP_ENTRY_VALID)) { + struct net_device *route_dev; + ether_addr_copy(e->h_dest, ha); ether_addr_copy(eth->h_dest, ha); /* Update the encap source mac, in case that we delete * the flows when encap source mac changed. */ - ether_addr_copy(eth->h_source, e->route_dev->dev_addr); + route_dev = __dev_get_by_index(dev_net(priv->netdev), e->route_dev_ifindex); + if (route_dev) + ether_addr_copy(eth->h_source, route_dev->dev_addr); mlx5e_tc_encap_flows_add(priv, e, &flow_list); } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c index 7cce85faa16f..90930e54b6f2 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c @@ -77,13 +77,13 @@ static int get_route_and_out_devs(struct mlx5e_priv *priv, return 0; } -static int mlx5e_route_lookup_ipv4(struct mlx5e_priv *priv, - struct net_device *mirred_dev, - struct net_device **out_dev, - struct net_device **route_dev, - struct flowi4 *fl4, - struct neighbour **out_n, - u8 *out_ttl) +static int mlx5e_route_lookup_ipv4_get(struct mlx5e_priv *priv, + struct net_device *mirred_dev, + struct net_device **out_dev, + struct net_device **route_dev, + struct flowi4 *fl4, + struct neighbour **out_n, + u8 *out_ttl) { struct neighbour *n; struct rtable *rt; @@ -117,18 +117,28 @@ static int mlx5e_route_lookup_ipv4(struct mlx5e_priv *priv, ip_rt_put(rt); return ret; } + dev_hold(*route_dev); if (!(*out_ttl)) *out_ttl = ip4_dst_hoplimit(&rt->dst); n = dst_neigh_lookup(&rt->dst, &fl4->daddr); ip_rt_put(rt); - if (!n) + if (!n) { + dev_put(*route_dev); return -ENOMEM; + } *out_n = n; return 0; } +static void mlx5e_route_lookup_ipv4_put(struct net_device *route_dev, + struct neighbour *n) +{ + neigh_release(n); + dev_put(route_dev); +} + static const char *mlx5e_netdev_kind(struct net_device *dev) { if (dev->rtnl_link_ops) @@ -193,8 +203,8 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, fl4.saddr = tun_key->u.ipv4.src; ttl = tun_key->ttl; - err = mlx5e_route_lookup_ipv4(priv, mirred_dev, &out_dev, &route_dev, - &fl4, &n, &ttl); + err = mlx5e_route_lookup_ipv4_get(priv, mirred_dev, &out_dev, &route_dev, + &fl4, &n, &ttl); if (err) return err; @@ -223,7 +233,7 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, e->m_neigh.family = n->ops->family; memcpy(&e->m_neigh.dst_ip, n->primary_key, n->tbl->key_len); e->out_dev = out_dev; - e->route_dev = route_dev; + e->route_dev_ifindex = route_dev->ifindex; /* It's important to add the neigh to the hash table before checking * the neigh validity state. So if we'll get a notification, in case the @@ -278,7 +288,7 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, e->flags |= MLX5_ENCAP_ENTRY_VALID; mlx5e_rep_queue_neigh_stats_work(netdev_priv(out_dev)); - neigh_release(n); + mlx5e_route_lookup_ipv4_put(route_dev, n); return err; destroy_neigh_entry: @@ -286,18 +296,18 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, free_encap: kfree(encap_header); release_neigh: - neigh_release(n); + mlx5e_route_lookup_ipv4_put(route_dev, n); return err; } #if IS_ENABLED(CONFIG_INET) && IS_ENABLED(CONFIG_IPV6) -static int mlx5e_route_lookup_ipv6(struct mlx5e_priv *priv, - struct net_device *mirred_dev, - struct net_device **out_dev, - struct net_device **route_dev, - struct flowi6 *fl6, - struct neighbour **out_n, - u8 *out_ttl) +static int mlx5e_route_lookup_ipv6_get(struct mlx5e_priv *priv, + struct net_device *mirred_dev, + struct net_device **out_dev, + struct net_device **route_dev, + struct flowi6 *fl6, + struct neighbour **out_n, + u8 *out_ttl) { struct dst_entry *dst; struct neighbour *n; @@ -318,15 +328,25 @@ static int mlx5e_route_lookup_ipv6(struct mlx5e_priv *priv, return ret; } + dev_hold(*route_dev); n = dst_neigh_lookup(dst, &fl6->daddr); dst_release(dst); - if (!n) + if (!n) { + dev_put(*route_dev); return -ENOMEM; + } *out_n = n; return 0; } +static void mlx5e_route_lookup_ipv6_put(struct net_device *route_dev, + struct neighbour *n) +{ + neigh_release(n); + dev_put(route_dev); +} + int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, struct net_device *mirred_dev, struct mlx5e_encap_entry *e) @@ -348,8 +368,8 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, fl6.daddr = tun_key->u.ipv6.dst; fl6.saddr = tun_key->u.ipv6.src; - err = mlx5e_route_lookup_ipv6(priv, mirred_dev, &out_dev, &route_dev, - &fl6, &n, &ttl); + err = mlx5e_route_lookup_ipv6_get(priv, mirred_dev, &out_dev, &route_dev, + &fl6, &n, &ttl); if (err) return err; @@ -378,7 +398,7 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, e->m_neigh.family = n->ops->family; memcpy(&e->m_neigh.dst_ip, n->primary_key, n->tbl->key_len); e->out_dev = out_dev; - e->route_dev = route_dev; + e->route_dev_ifindex = route_dev->ifindex; /* It's importent to add the neigh to the hash table before checking * the neigh validity state. So if we'll get a notification, in case the @@ -433,7 +453,7 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, e->flags |= MLX5_ENCAP_ENTRY_VALID; mlx5e_rep_queue_neigh_stats_work(netdev_priv(out_dev)); - neigh_release(n); + mlx5e_route_lookup_ipv6_put(route_dev, n); return err; destroy_neigh_entry: @@ -441,7 +461,7 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, free_encap: kfree(encap_header); release_neigh: - neigh_release(n); + mlx5e_route_lookup_ipv6_put(route_dev, n); return err; } #endif diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h index 9020d1419bcf..8932c387d46a 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h @@ -186,7 +186,7 @@ struct mlx5e_encap_entry { unsigned char h_dest[ETH_ALEN]; /* destination eth addr */ struct net_device *out_dev; - struct net_device *route_dev; + int route_dev_ifindex; struct mlx5e_tc_tunnel *tunnel; int reformat_type; u8 flags;