From patchwork Wed May 12 14:51:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 437806 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 16978C43461 for ; Wed, 12 May 2021 17:05:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D3C6C613CB for ; Wed, 12 May 2021 17:05:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236288AbhELRGI (ORCPT ); Wed, 12 May 2021 13:06:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:48504 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237994AbhELQtf (ORCPT ); Wed, 12 May 2021 12:49:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8C91761D70; Wed, 12 May 2021 16:16:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620836165; bh=YzsIS8v4mpKmWDdMV6RN/8wpsZ2+pygsMwrWVJ/trx8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gm1F8pO0EdzAnHZ3hJMMCrZfSIDKMq7fIMmYGPtBc0IexPeaTNYDGs5X5sROJOZBI Hw0fUVPp4oKgZ/FbYE2pbScbPS1pcXS8dicCQvGm7ZyDOxRf6q5K8t32BcnQUO2d9D GJnH9lZwJEI4a6/SrhCXsY02kpadr9bUapIw9nfc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Martin Willi , Daniel Borkmann , =?utf-8?q?Toke_H=C3=B8iland-J?= =?utf-8?b?w7hyZ2Vuc2Vu?= , Sasha Levin Subject: [PATCH 5.12 635/677] net, xdp: Update pkt_type if generic XDP changes unicast MAC Date: Wed, 12 May 2021 16:51:21 +0200 Message-Id: <20210512144858.460538181@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144837.204217980@linuxfoundation.org> References: <20210512144837.204217980@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Martin Willi [ Upstream commit 22b6034323fd736f260e00b9ea85c634abeb3446 ] If a generic XDP program changes the destination MAC address from/to multicast/broadcast, the skb->pkt_type is updated to properly handle the packet when passed up the stack. When changing the MAC from/to the NICs MAC, PACKET_HOST/OTHERHOST is not updated, though, making the behavior different from that of native XDP. Remember the PACKET_HOST/OTHERHOST state before calling the program in generic XDP, and update pkt_type accordingly if the destination MAC address has changed. As eth_type_trans() assumes a default pkt_type of PACKET_HOST, restore that before calling it. The use case for this is when a XDP program wants to push received packets up the stack by rewriting the MAC to the NICs MAC, for example by cluster nodes sharing MAC addresses. Fixes: 297249569932 ("net: fix generic XDP to handle if eth header was mangled") Signed-off-by: Martin Willi Signed-off-by: Daniel Borkmann Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20210419141559.8611-1-martin@strongswan.org Signed-off-by: Sasha Levin --- net/core/dev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 15fe36332fb8..70829c568645 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4672,10 +4672,10 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb, void *orig_data, *orig_data_end, *hard_start; struct netdev_rx_queue *rxqueue; u32 metalen, act = XDP_DROP; + bool orig_bcast, orig_host; u32 mac_len, frame_sz; __be16 orig_eth_type; struct ethhdr *eth; - bool orig_bcast; int off; /* Reinjected packets coming from act_mirred or similar should @@ -4722,6 +4722,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb, orig_data_end = xdp->data_end; orig_data = xdp->data; eth = (struct ethhdr *)xdp->data; + orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); orig_eth_type = eth->h_proto; @@ -4749,8 +4750,11 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb, /* check if XDP changed eth hdr such SKB needs update */ eth = (struct ethhdr *)xdp->data; if ((orig_eth_type != eth->h_proto) || + (orig_host != ether_addr_equal_64bits(eth->h_dest, + skb->dev->dev_addr)) || (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { __skb_push(skb, ETH_HLEN); + skb->pkt_type = PACKET_HOST; skb->protocol = eth_type_trans(skb, skb->dev); }