{"id":2231611,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2231611/?format=json","web_url":"http://patchwork.ozlabs.org/project/netfilter-devel/patch/20260430232559.285492-3-pablo@netfilter.org/","project":{"id":26,"url":"http://patchwork.ozlabs.org/api/1.1/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},"msgid":"<20260430232559.285492-3-pablo@netfilter.org>","date":"2026-04-30T23:25:57","name":"[nf,v7,3/4] netfilter: flowtable: fix inline pppoe encapsulation in xmit path","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"a8f612d5dfdd3f41e0c35662ae90f3dad9b687e3","submitter":{"id":1315,"url":"http://patchwork.ozlabs.org/api/1.1/people/1315/?format=json","name":"Pablo Neira Ayuso","email":"pablo@netfilter.org"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/netfilter-devel/patch/20260430232559.285492-3-pablo@netfilter.org/mbox/","series":[{"id":502404,"url":"http://patchwork.ozlabs.org/api/1.1/series/502404/?format=json","web_url":"http://patchwork.ozlabs.org/project/netfilter-devel/list/?series=502404","date":"2026-04-30T23:25:55","name":"[nf,v7,1/4] netfilter: flowtable: ensure sufficient headroom in xmit path","version":7,"mbox":"http://patchwork.ozlabs.org/series/502404/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2231611/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2231611/checks/","tags":{},"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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d=netfilter.org;\n\ts=2025; t=1777591564;\n\tbh=/njnH8xJNIDyXXjwEvGdVa401h8ghF2o1t/OZJgKUD4=;\n\th=From:To:Subject:Date:In-Reply-To:References:From;\n\tb=n2fgqr2Uek0T7iZhqWpcgfP7C8/5zXGUPHJCUGk4JqDuO2svSWuW2Uzj6nTM1Kyk+\n\t 8Ff8W6Qv/j++ThZf2bD62g3ktVmuD76teQZtPOAbc2VPFfREehVereTtU2iwF4Y45j\n\t wLM1ZgyBIO8RpGYHqPO3UqafIwE0WCpkXmE/EjhZcLFXQcWKHClniyVHxVshzc5zwn\n\t g74AsHGdAb9CQf6wntRiFldC5RI/xFXNWEDM2+HD05ZEQsF/PE/8vrOvCXOA1ICYvf\n\t Bm8coHPKCc0IwK8gJav+Q1ixZz9N0kkuyp0F9y0oTD1cjx8wtlAkAfoZWuJLZndvfE\n\t Hd/i+nEl7JzVw==","From":"Pablo Neira Ayuso ","To":"netfilter-devel@vger.kernel.org","Subject":"[PATCH nf,v7 3/4] netfilter: flowtable: fix inline pppoe\n encapsulation in xmit path","Date":"Fri, 1 May 2026 01:25:57 +0200","Message-ID":"<20260430232559.285492-3-pablo@netfilter.org>","X-Mailer":"git-send-email 2.47.3","In-Reply-To":"<20260430232559.285492-1-pablo@netfilter.org>","References":"<20260430232559.285492-1-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---\nv7: no changes\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 | 42 +++++++++++++++++++++++++--\n net/netfilter/nf_flow_table_path.c | 7 ++++-\n 4 files changed, 49 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 0ce3c209050c..2eba64eb393a 100644\n--- a/net/netfilter/nf_flow_table_ip.c\n+++ b/net/netfilter/nf_flow_table_ip.c\n@@ -553,7 +553,8 @@ 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@@ -562,7 +563,7 @@ 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@@ -755,7 +756,8 @@ 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@@ -769,6 +771,7 @@ struct nf_flow_xmit {\n \tconst void\t\t*source;\n \tstruct net_device\t*outdev;\n \tstruct flow_offload_tuple *tuple;\n+\tbool\t\t\tneeds_gso_segment;\n };\n \n static void __nf_flow_queue_xmit(struct net *net, struct sk_buff *skb,\n@@ -789,10 +792,41 @@ 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))\n+\t\treturn NF_DROP;\n+\n+\tif (segs)\n+\t\tconsume_skb(skb);\n+\telse\n+\t\tsegs = skb;\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(segs);\n+\t\t\tkfree_skb_list(nskb);\n+\t\t\treturn NF_STOLEN;\n+\t\t}\n+\t\t__nf_flow_queue_xmit(net, segs, xmit);\n+\t}\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->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}\n@@ -876,6 +910,7 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,\n \t\treturn NF_DROP;\n \t}\n \txmit.tuple = other_tuple;\n+\txmit.needs_gso_segment = tuplehash->tuple.needs_gso_segment;\n \n \treturn nf_flow_queue_xmit(state->net, skb, &xmit);\n }\n@@ -1196,6 +1231,7 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,\n \t\treturn NF_DROP;\n \t}\n \txmit.tuple = other_tuple;\n+\txmit.needs_gso_segment = tuplehash->tuple.needs_gso_segment;\n \n \treturn nf_flow_queue_xmit(state->net, skb, &xmit);\n }\ndiff --git a/net/netfilter/nf_flow_table_path.c b/net/netfilter/nf_flow_table_path.c\nindex 6bb9579dcc2a..9e88ea6a2eef 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","v7","3/4"]}