{"id":2227819,"url":"http://patchwork.ozlabs.org/api/patches/2227819/?format=json","web_url":"http://patchwork.ozlabs.org/project/netfilter-devel/patch/20260424100759.534113-2-pablo@netfilter.org/","project":{"id":26,"url":"http://patchwork.ozlabs.org/api/projects/26/?format=json","name":"Netfilter Development","link_name":"netfilter-devel","list_id":"netfilter-devel.vger.kernel.org","list_email":"netfilter-devel@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260424100759.534113-2-pablo@netfilter.org>","list_archive_url":null,"date":"2026-04-24T10:07:59","name":"[nf,2/2] netfilter: flowtable: fix inline pppoe encapsulation in xmit path","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"331feb3a0bcc40fbd829262465ecd94d3d256b13","submitter":{"id":1315,"url":"http://patchwork.ozlabs.org/api/people/1315/?format=json","name":"Pablo Neira Ayuso","email":"pablo@netfilter.org"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/netfilter-devel/patch/20260424100759.534113-2-pablo@netfilter.org/mbox/","series":[{"id":501336,"url":"http://patchwork.ozlabs.org/api/series/501336/?format=json","web_url":"http://patchwork.ozlabs.org/project/netfilter-devel/list/?series=501336","date":"2026-04-24T10:07:58","name":"[nf,1/2] netfilter: flowtable: fix inline vlan encapsulation in xmit path","version":1,"mbox":"http://patchwork.ozlabs.org/series/501336/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2227819/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2227819/checks/","tags":{},"related":[],"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","netfilter-devel@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=netfilter.org 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Fri, 24 Apr 2026 20:11:38 +1000 (AEST)","from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sea.lore.kernel.org (Postfix) with ESMTP id 8D04D301FFB3\n\tfor ; Fri, 24 Apr 2026 10:08:15 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id B86C4363092;\n\tFri, 24 Apr 2026 10:08:14 +0000 (UTC)","from mail.netfilter.org (mail.netfilter.org [217.70.190.124])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id 44555359A91\n\tfor ; Fri, 24 Apr 2026 10:08:11 +0000 (UTC)","from localhost.localdomain (mail-agni [217.70.190.124])\n\tby mail.netfilter.org (Postfix) with ESMTPSA id 3C92C60273\n\tfor ; Fri, 24 Apr 2026 12:08:04 +0200 (CEST)"],"ARC-Seal":"i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1777025294; cv=none;\n 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t=1777025284;\n\tbh=FBRIyjrJW8V7/10pYI0D3ipZCNBV3Szr6/L6LixOyYU=;\n\th=From:To:Subject:Date:In-Reply-To:References:From;\n\tb=v8ucVnj0jFVR/S5qKXgOWXJd1k5vM12x2hoWGBEqbOvyZDKPhgWaG2tuh3XAWechi\n\t cVfTh92Dy9Zmbzx4DEP32Hh6u6tDhrTXLPTO2Rw4W/TaCRPvMSdhDURZQ2RVaYCkq/\n\t r9AUuCbU58vAQMflr+k0M1kCaCTOVxeKq5KoxzxZWsgC4f8bp1d2tM29z0i03CVM+8\n\t rt0lDGHe8iACFpHXE4eCxzXS9fTqQQoqT+S+D3E6eI5M6TSJFNW/9OKeI2sgnO/X6N\n\t BuCUmLn0v4k+g7eWvKT8+q9ivHGMp8X7ki5K9jDzvRQdstS27h5wauauXlsVI+7cb2\n\t U62WyS77TOAvQ==","From":"Pablo Neira Ayuso ","To":"netfilter-devel@vger.kernel.org","Subject":"[PATCH nf 2/2] netfilter: flowtable: fix inline pppoe encapsulation\n in xmit path","Date":"Fri, 24 Apr 2026 12:07:59 +0200","Message-ID":"<20260424100759.534113-2-pablo@netfilter.org>","X-Mailer":"git-send-email 2.47.3","In-Reply-To":"<20260424100759.534113-1-pablo@netfilter.org>","References":"<20260424100759.534113-1-pablo@netfilter.org>","Precedence":"bulk","X-Mailing-List":"netfilter-devel@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit"},"content":"Address two issues in the inline pppoe encapsulation:\n\n- Add needs_gso_segment flag to segment PPPoE packets in software\n given that there is no GSO support for this.\n\n- Use FLOW_OFFLOAD_XMIT_DIRECT since neighbour cache is not available\n in point-to-point device, use the hardware address that is obtained\n via flowtable path discovery (ie. fill_forward_path).\n\nFixes: 18d27bed0880 (\"netfilter: flowtable: inline pppoe encapsulation in xmit path\")\nSigned-off-by: Pablo Neira Ayuso \n---\nTested locally with a pppoe server in my network and pppoe client in a netns inside VM,\nit shows an improvement of 70% in bandwith with iperf3 when forwarding pppoe traffic\nthrough the flowtable here compared to classic forwarding.\n\n include/net/netfilter/nf_flow_table.h | 4 +++-\n net/netfilter/nf_flow_table_core.c | 1 +\n net/netfilter/nf_flow_table_ip.c | 34 ++++++++++++++++++++++++---\n net/netfilter/nf_flow_table_path.c | 7 +++++-\n 4 files changed, 41 insertions(+), 5 deletions(-)","diff":"diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h\nindex b09c11c048d5..7b23b245a5a8 100644\n--- a/include/net/netfilter/nf_flow_table.h\n+++ b/include/net/netfilter/nf_flow_table.h\n@@ -148,9 +148,10 @@ struct flow_offload_tuple {\n \t/* All members above are keys for lookups, see flow_offload_hash(). */\n \tstruct { }\t\t\t__hash;\n \n-\tu8\t\t\t\tdir:2,\n+\tu16\t\t\t\tdir:2,\n \t\t\t\t\txmit_type:3,\n \t\t\t\t\tencap_num:2,\n+\t\t\t\t\tneeds_gso_segment:1,\n \t\t\t\t\ttun_num:2,\n \t\t\t\t\tin_vlan_ingress:2;\n \tu16\t\t\t\tmtu;\n@@ -232,6 +233,7 @@ struct nf_flow_route {\n \t\t\tu32\t\t\thw_ifindex;\n \t\t\tu8\t\t\th_source[ETH_ALEN];\n \t\t\tu8\t\t\th_dest[ETH_ALEN];\n+\t\t\tu8\t\t\tneeds_gso_segment:1;\n \t\t} out;\n \t\tenum flow_offload_xmit_type\txmit_type;\n \t} tuple[FLOW_OFFLOAD_DIR_MAX];\ndiff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c\nindex 2c4140e6f53c..785d8c244a77 100644\n--- a/net/netfilter/nf_flow_table_core.c\n+++ b/net/netfilter/nf_flow_table_core.c\n@@ -122,6 +122,7 @@ static int flow_offload_fill_route(struct flow_offload *flow,\n \n \tflow_tuple->tun = route->tuple[dir].in.tun;\n \tflow_tuple->encap_num = route->tuple[dir].in.num_encaps;\n+\tflow_tuple->needs_gso_segment = route->tuple[dir].out.needs_gso_segment;\n \tflow_tuple->tun_num = route->tuple[dir].in.num_tuns;\n \n \tswitch (route->tuple[dir].xmit_type) {\ndiff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c\nindex 1573189a23a1..c3aa5df9b724 100644\n--- a/net/netfilter/nf_flow_table_ip.c\n+++ b/net/netfilter/nf_flow_table_ip.c\n@@ -552,7 +552,8 @@ static int nf_flow_vlan_push(struct sk_buff *skb, __be16 proto, u16 id,\n \treturn 0;\n }\n \n-static int nf_flow_pppoe_push(struct sk_buff *skb, u16 id)\n+static int nf_flow_pppoe_push(struct sk_buff *skb, u16 id,\n+\t\t\t u32 needed_headroom)\n {\n \tint data_len = skb->len + sizeof(__be16);\n \tstruct ppp_hdr {\n@@ -561,7 +562,7 @@ static int nf_flow_pppoe_push(struct sk_buff *skb, u16 id)\n \t} *ph;\n \t__be16 proto;\n \n-\tif (skb_cow_head(skb, PPPOE_SES_HLEN))\n+\tif (skb_cow_head(skb, needed_headroom + PPPOE_SES_HLEN))\n \t\treturn -1;\n \n \tswitch (skb->protocol) {\n@@ -754,7 +755,8 @@ static int nf_flow_encap_push(struct sk_buff *skb,\n \t\t\t\treturn -1;\n \t\t\tbreak;\n \t\tcase htons(ETH_P_PPP_SES):\n-\t\t\tif (nf_flow_pppoe_push(skb, tuple->encap[i].id) < 0)\n+\t\t\tif (nf_flow_pppoe_push(skb, tuple->encap[i].id,\n+\t\t\t\t\t needed_headroom) < 0)\n \t\t\t\treturn -1;\n \t\t\tbreak;\n \t\t}\n@@ -779,10 +781,36 @@ static void __nf_flow_queue_xmit(struct net *net, struct sk_buff *skb,\n \tdev_queue_xmit(skb);\n }\n \n+static unsigned int nf_flow_encap_gso_xmit(struct net *net, struct sk_buff *skb,\n+\t\t\t\t\t struct nf_flow_xmit *xmit)\n+{\n+\tstruct sk_buff *segs, *nskb;\n+\n+\tsegs = skb_gso_segment(skb, 0);\n+\tif (IS_ERR(segs) || !segs)\n+\t\treturn NF_DROP;\n+\n+\tskb_list_walk_safe(segs, segs, nskb) {\n+\t\tskb_mark_not_on_list(segs);\n+\n+\t\tif (nf_flow_encap_push(segs, xmit->tuple, xmit->outdev) < 0) {\n+\t\t\tkfree_skb_list(nskb);\n+\t\t\treturn NF_DROP;\n+\t\t}\n+\t\t__nf_flow_queue_xmit(net, segs, xmit);\n+\t}\n+\tconsume_skb(skb);\n+\n+\treturn NF_STOLEN;\n+}\n+\n static unsigned int nf_flow_queue_xmit(struct net *net, struct sk_buff *skb,\n \t\t\t\t struct nf_flow_xmit *xmit)\n {\n \tif (xmit->tuple->encap_num) {\n+\t\tif (skb_is_gso(skb) && xmit->tuple->needs_gso_segment)\n+\t\t\treturn nf_flow_encap_gso_xmit(net, skb, xmit);\n+\n \t\tif (nf_flow_encap_push(skb, xmit->tuple, xmit->outdev) < 0)\n \t\t\treturn NF_DROP;\n \t}\ndiff --git a/net/netfilter/nf_flow_table_path.c b/net/netfilter/nf_flow_table_path.c\nindex 6bb9579dcc2a..37f7b590c531 100644\n--- a/net/netfilter/nf_flow_table_path.c\n+++ b/net/netfilter/nf_flow_table_path.c\n@@ -86,6 +86,7 @@ struct nft_forward_info {\n \tu8 ingress_vlans;\n \tu8 h_source[ETH_ALEN];\n \tu8 h_dest[ETH_ALEN];\n+\tbool needs_gso_segment;\n \tenum flow_offload_xmit_type xmit_type;\n };\n \n@@ -138,8 +139,11 @@ static void nft_dev_path_info(const struct net_device_path_stack *stack,\n \t\t\t\t\tpath->encap.proto;\n \t\t\t\tinfo->num_encaps++;\n \t\t\t}\n-\t\t\tif (path->type == DEV_PATH_PPPOE)\n+\t\t\tif (path->type == DEV_PATH_PPPOE) {\n \t\t\t\tmemcpy(info->h_dest, path->encap.h_dest, ETH_ALEN);\n+\t\t\t\tinfo->xmit_type = FLOW_OFFLOAD_XMIT_DIRECT;\n+\t\t\t\tinfo->needs_gso_segment = 1;\n+\t\t\t}\n \t\t\tbreak;\n \t\tcase DEV_PATH_BRIDGE:\n \t\t\tif (is_zero_ether_addr(info->h_source))\n@@ -279,6 +283,7 @@ static void nft_dev_forward_path(const struct nft_pktinfo *pkt,\n \t\tmemcpy(route->tuple[dir].out.h_dest, info.h_dest, ETH_ALEN);\n \t\troute->tuple[dir].xmit_type = info.xmit_type;\n \t}\n+\troute->tuple[!dir].out.needs_gso_segment = info.needs_gso_segment;\n }\n \n int nft_flow_route(const struct nft_pktinfo *pkt, const struct nf_conn *ct,\n","prefixes":["nf","2/2"]}