Commit eaafdaa3 authored Mar 07, 2023 by Xin Long Committed by Florian Westphal Mar 08, 2023

netfilter: use nf_ip6_check_hbh_len in nf_ct_skb_network_trim



For IPv6 Jumbo packets, the ipv6_hdr(skb)->payload_len is always 0,
and its real payload_len ( > 65535) is saved in hbh exthdr. With 0
length for the jumbo packets, all data and exthdr will be trimmed
in nf_ct_skb_network_trim().

This patch is to call nf_ip6_check_hbh_len() to get real pkt_len
of the IPv6 packet, similar to br_validate_ipv6().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

parent 28e144cf

net/netfilter/nf_conntrack_ovs.c

+9 −2

Original line number	Diff line number	Diff line
		@@ -6,6 +6,7 @@
		#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
		#include <net/ipv6_frag.h>
		#include <net/ip.h>
		#include <linux/netfilter_ipv6.h>

		/* 'skb' should already be pulled to nh_ofs. */
		int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,
		@@ -120,8 +121,14 @@ int nf_ct_skb_network_trim(struct sk_buff *skb, int family)
		len = skb_ip_totlen(skb);
		break;
		case NFPROTO_IPV6:
		len = sizeof(struct ipv6hdr)
		+ ntohs(ipv6_hdr(skb)->payload_len);
		len = ntohs(ipv6_hdr(skb)->payload_len);
		if (ipv6_hdr(skb)->nexthdr == NEXTHDR_HOP) {
		int err = nf_ip6_check_hbh_len(skb, &len);

		if (err)
		return err;
		}
		len += sizeof(struct ipv6hdr);
		break;
		default:
		len = skb->len;