From 6aafeef03b9d9ecf255f3a80ed85ee070260e1ae Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Wed, 6 Nov 2013 17:52:20 +0100 Subject: netfilter: push reasm skb through instead of original frag skbs Pushing original fragments through causes several problems. For example for matching, frags may not be matched correctly. Take following example: On HOSTA do: ip6tables -I INPUT -p icmpv6 -j DROP ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT and on HOSTB you do: ping6 HOSTA -s2000 (MTU is 1500) Incoming echo requests will be filtered out on HOSTA. This issue does not occur with smaller packets than MTU (where fragmentation does not happen) As was discussed previously, the only correct solution seems to be to use reassembled skb instead of separete frags. Doing this has positive side effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams dances in ipvs and conntrack can be removed. Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c entirely and use code in net/ipv6/reassembly.c instead. Signed-off-by: Jiri Pirko Acked-by: Julian Anastasov Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- include/net/ip_vs.h | 32 +------------------------------- 1 file changed, 1 insertion(+), 31 deletions(-) (limited to 'include/net/ip_vs.h') diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index cd7275f9c463..5679d927562b 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -109,7 +109,6 @@ extern int ip_vs_conn_tab_size; struct ip_vs_iphdr { __u32 len; /* IPv4 simply where L4 starts IPv6 where L4 Transport Header starts */ - __u32 thoff_reasm; /* Transport Header Offset in nfct_reasm skb */ __u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/ __s16 protocol; __s32 flags; @@ -117,34 +116,12 @@ struct ip_vs_iphdr { union nf_inet_addr daddr; }; -/* Dependency to module: nf_defrag_ipv6 */ -#if defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE) -static inline struct sk_buff *skb_nfct_reasm(const struct sk_buff *skb) -{ - return skb->nfct_reasm; -} -static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset, - int len, void *buffer, - const struct ip_vs_iphdr *ipvsh) -{ - if (unlikely(ipvsh->fragoffs && skb_nfct_reasm(skb))) - return skb_header_pointer(skb_nfct_reasm(skb), - ipvsh->thoff_reasm, len, buffer); - - return skb_header_pointer(skb, offset, len, buffer); -} -#else -static inline struct sk_buff *skb_nfct_reasm(const struct sk_buff *skb) -{ - return NULL; -} static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset, int len, void *buffer, const struct ip_vs_iphdr *ipvsh) { return skb_header_pointer(skb, offset, len, buffer); } -#endif static inline void ip_vs_fill_ip4hdr(const void *nh, struct ip_vs_iphdr *iphdr) @@ -171,19 +148,12 @@ ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, struct ip_vs_iphdr *iphdr) (struct ipv6hdr *)skb_network_header(skb); iphdr->saddr.in6 = iph->saddr; iphdr->daddr.in6 = iph->daddr; - /* ipv6_find_hdr() updates len, flags, thoff_reasm */ - iphdr->thoff_reasm = 0; + /* ipv6_find_hdr() updates len, flags */ iphdr->len = 0; iphdr->flags = 0; iphdr->protocol = ipv6_find_hdr(skb, &iphdr->len, -1, &iphdr->fragoffs, &iphdr->flags); - /* get proto from re-assembled packet and it's offset */ - if (skb_nfct_reasm(skb)) - iphdr->protocol = ipv6_find_hdr(skb_nfct_reasm(skb), - &iphdr->thoff_reasm, - -1, NULL, NULL); - } else #endif { -- cgit v1.2.3