From patchwork Mon Jan 3 17:12:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Simon Wunderlich X-Patchwork-Id: 18441 X-Patchwork-Delegate: sw@simonwunderlich.de Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from diktynna.open-mesh.org (localhost [IPv6:::1]) by diktynna.open-mesh.org (Postfix) with ESMTP id 6CD9483EFB; Mon, 3 Jan 2022 18:12:12 +0100 (CET) Received: from simonwunderlich.de (simonwunderlich.de [23.88.38.48]) by diktynna.open-mesh.org (Postfix) with ESMTPS id 0FA1983E8B for ; Mon, 3 Jan 2022 18:12:08 +0100 (CET) Received: from kero.packetmixer.de (p200300C597476fc09Af9dad664F33736.dip0.t-ipconnect.de [IPv6:2003:c5:9747:6fc0:9af9:dad6:64f3:3736]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simonwunderlich.de (Postfix) with ESMTPSA id AC149FA1B7; Mon, 3 Jan 2022 18:12:07 +0100 (CET) From: Simon Wunderlich To: davem@davemloft.net, kuba@kernel.org Subject: [PATCH 1/1] batman-adv: mcast: don't send link-local multicast to mcast routers Date: Mon, 3 Jan 2022 18:12:03 +0100 Message-Id: <20220103171203.1124980-2-sw@simonwunderlich.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220103171203.1124980-1-sw@simonwunderlich.de> References: <20220103171203.1124980-1-sw@simonwunderlich.de> MIME-Version: 1.0 ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=none; spf=pass (diktynna.open-mesh.org: domain of sw@simonwunderlich.de designates 23.88.38.48 as permitted sender) smtp.mailfrom=sw@simonwunderlich.de; dmarc=none ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1641229928; a=rsa-sha256; cv=none; b=RnHzqM18svrcF6aXs/kzMPzKwBUst224WtC8MyMjrPNN8oF8Pzwr9zCF7u+0M6hQHqxCTq maHSsVWHUv9+mZj5YHpDzUq3a8mQ2VLlkldBaPv/1wr+xRgR+mFNpv3+jnk0knik56bANM bgqRS0lUa/nhSDrHdDlUjyar/a1M0Pc= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1641229928; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=M0zr2nLgAYcP4gU3XbA+CuYIuesGo/YcK7AJ/BCWG84=; b=lLivWadOXm9+7b6l9foMM5jKv77N5uNj/MkMlUQGnKeT7jF4oqrSGhN6dJy7JzOwsDITI/ c6B/B2xz8b2uwPh0coD+gNo+a709v4ztz9Z3FuMBtz/+1HyAqQz3pdmW3SDZ8iUlTXLoYg hq2aEUD1t0A4A2BGJ+3cPz1/ilNWgqU= Message-ID-Hash: NRQPDOJPCI7HXDO66R7UOL5ZG5PEOHOQ X-Message-ID-Hash: NRQPDOJPCI7HXDO66R7UOL5ZG5PEOHOQ X-MailFrom: sw@simonwunderlich.de X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-b.a.t.m.a.n.lists.open-mesh.org-0; header-match-b.a.t.m.a.n.lists.open-mesh.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 3.2.1 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: From: Linus Lüssing The addition of routable multicast TX handling introduced a bug/regression for packets with a link-local multicast destination: These packets would be sent to all batman-adv nodes with a multicast router and to all batman-adv nodes with an old version without multicast router detection. This even disregards the batman-adv multicast fanout setting, which can potentially lead to an unwanted, high number of unicast transmissions or even congestion. Fixing this by avoiding to send link-local multicast packets to nodes in the multicast router list. Fixes: 11d458c1cb9b ("batman-adv: mcast: apply optimizations for routable packets, too") Signed-off-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich --- net/batman-adv/multicast.c | 15 ++++++++++----- net/batman-adv/multicast.h | 10 ++++++---- net/batman-adv/soft-interface.c | 7 +++++-- 3 files changed, 21 insertions(+), 11 deletions(-) diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c index 433901dcf0c3..f4004cf0ff6f 100644 --- a/net/batman-adv/multicast.c +++ b/net/batman-adv/multicast.c @@ -1339,6 +1339,7 @@ batadv_mcast_forw_rtr_node_get(struct batadv_priv *bat_priv, * @bat_priv: the bat priv with all the soft interface information * @skb: The multicast packet to check * @orig: an originator to be set to forward the skb to + * @is_routable: stores whether the destination is routable * * Return: the forwarding mode as enum batadv_forw_mode and in case of * BATADV_FORW_SINGLE set the orig to the single originator the skb @@ -1346,17 +1347,16 @@ batadv_mcast_forw_rtr_node_get(struct batadv_priv *bat_priv, */ enum batadv_forw_mode batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, - struct batadv_orig_node **orig) + struct batadv_orig_node **orig, int *is_routable) { int ret, tt_count, ip_count, unsnoop_count, total_count; bool is_unsnoopable = false; unsigned int mcast_fanout; struct ethhdr *ethhdr; - int is_routable = 0; int rtr_count = 0; ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable, - &is_routable); + is_routable); if (ret == -ENOMEM) return BATADV_FORW_NONE; else if (ret < 0) @@ -1369,7 +1369,7 @@ batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr); unsnoop_count = !is_unsnoopable ? 0 : atomic_read(&bat_priv->mcast.num_want_all_unsnoopables); - rtr_count = batadv_mcast_forw_rtr_count(bat_priv, is_routable); + rtr_count = batadv_mcast_forw_rtr_count(bat_priv, *is_routable); total_count = tt_count + ip_count + unsnoop_count + rtr_count; @@ -1689,6 +1689,7 @@ batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv, * @bat_priv: the bat priv with all the soft interface information * @skb: the multicast packet to transmit * @vid: the vlan identifier + * @is_routable: stores whether the destination is routable * * Sends copies of a frame with multicast destination to any node that signaled * interest in it, that is either via the translation table or the according @@ -1701,7 +1702,7 @@ batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv, * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise. */ int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb, - unsigned short vid) + unsigned short vid, int is_routable) { int ret; @@ -1717,12 +1718,16 @@ int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb, return ret; } + if (!is_routable) + goto skip_mc_router; + ret = batadv_mcast_forw_want_rtr(bat_priv, skb, vid); if (ret != NET_XMIT_SUCCESS) { kfree_skb(skb); return ret; } +skip_mc_router: consume_skb(skb); return ret; } diff --git a/net/batman-adv/multicast.h b/net/batman-adv/multicast.h index 9fee5da08311..8aec818d0bf6 100644 --- a/net/batman-adv/multicast.h +++ b/net/batman-adv/multicast.h @@ -43,7 +43,8 @@ enum batadv_forw_mode { enum batadv_forw_mode batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, - struct batadv_orig_node **mcast_single_orig); + struct batadv_orig_node **mcast_single_orig, + int *is_routable); int batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv, struct sk_buff *skb, @@ -51,7 +52,7 @@ int batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node); int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb, - unsigned short vid); + unsigned short vid, int is_routable); void batadv_mcast_init(struct batadv_priv *bat_priv); @@ -68,7 +69,8 @@ void batadv_mcast_purge_orig(struct batadv_orig_node *orig_node); static inline enum batadv_forw_mode batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, - struct batadv_orig_node **mcast_single_orig) + struct batadv_orig_node **mcast_single_orig, + int *is_routable) { return BATADV_FORW_ALL; } @@ -85,7 +87,7 @@ batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv, static inline int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb, - unsigned short vid) + unsigned short vid, int is_routable) { kfree_skb(skb); return NET_XMIT_DROP; diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 7ee09337fc40..2dbbe6c19609 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -198,6 +198,7 @@ static netdev_tx_t batadv_interface_tx(struct sk_buff *skb, int gw_mode; enum batadv_forw_mode forw_mode = BATADV_FORW_SINGLE; struct batadv_orig_node *mcast_single_orig = NULL; + int mcast_is_routable = 0; int network_offset = ETH_HLEN; __be16 proto; @@ -300,7 +301,8 @@ static netdev_tx_t batadv_interface_tx(struct sk_buff *skb, send: if (do_bcast && !is_broadcast_ether_addr(ethhdr->h_dest)) { forw_mode = batadv_mcast_forw_mode(bat_priv, skb, - &mcast_single_orig); + &mcast_single_orig, + &mcast_is_routable); if (forw_mode == BATADV_FORW_NONE) goto dropped; @@ -359,7 +361,8 @@ static netdev_tx_t batadv_interface_tx(struct sk_buff *skb, ret = batadv_mcast_forw_send_orig(bat_priv, skb, vid, mcast_single_orig); } else if (forw_mode == BATADV_FORW_SOME) { - ret = batadv_mcast_forw_send(bat_priv, skb, vid); + ret = batadv_mcast_forw_send(bat_priv, skb, vid, + mcast_is_routable); } else { if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))