It is never accessed for reading and the only places that write to it are the icmp(6) handlers, which also set skb->nfct (and skb->nfctinfo). The conntrack core specifically checks for attached skb->nfct after ->error() invocation and returns early in this case. Signed-off-by: Florian Westphal <fw@xxxxxxxxx> --- Changes since v2: use u8 instead of legacy u_int_8t to silence checkpatch.pl also change sctp_error, this depends on patch https://patchwork.ozlabs.org/patch/710170/ ('netfilter: conntrack: validate SCTP crc32c in PREROUTING') to be applied before this one. include/net/netfilter/nf_conntrack_l4proto.h | 2 +- net/ipv4/netfilter/nf_conntrack_proto_icmp.c | 12 ++++++------ net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c | 12 ++++++------ net/netfilter/nf_conntrack_core.c | 3 +-- net/netfilter/nf_conntrack_proto_dccp.c | 1 - net/netfilter/nf_conntrack_proto_sctp.c | 2 +- net/netfilter/nf_conntrack_proto_tcp.c | 1 - net/netfilter/nf_conntrack_proto_udp.c | 3 +-- 8 files changed, 16 insertions(+), 20 deletions(-) diff --git a/include/net/netfilter/nf_conntrack_l4proto.h b/include/net/netfilter/nf_conntrack_l4proto.h index e7b836590f0b..85e993e278d5 100644 --- a/include/net/netfilter/nf_conntrack_l4proto.h +++ b/include/net/netfilter/nf_conntrack_l4proto.h @@ -55,7 +55,7 @@ struct nf_conntrack_l4proto { void (*destroy)(struct nf_conn *ct); int (*error)(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, - unsigned int dataoff, enum ip_conntrack_info *ctinfo, + unsigned int dataoff, u_int8_t pf, unsigned int hooknum); /* Print out the per-protocol part of the tuple. Return like seq_* */ diff --git a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c index d075b3cf2400..566afac98a88 100644 --- a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c +++ b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c @@ -128,13 +128,13 @@ static bool icmp_new(struct nf_conn *ct, const struct sk_buff *skb, /* Returns conntrack if it dealt with ICMP, and filled in skb fields */ static int icmp_error_message(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, - enum ip_conntrack_info *ctinfo, unsigned int hooknum) { struct nf_conntrack_tuple innertuple, origtuple; const struct nf_conntrack_l4proto *innerproto; const struct nf_conntrack_tuple_hash *h; const struct nf_conntrack_zone *zone; + enum ip_conntrack_info ctinfo; struct nf_conntrack_zone tmp; NF_CT_ASSERT(skb->nfct == NULL); @@ -160,7 +160,7 @@ icmp_error_message(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, return -NF_ACCEPT; } - *ctinfo = IP_CT_RELATED; + ctinfo = IP_CT_RELATED; h = nf_conntrack_find_get(net, zone, &innertuple); if (!h) { @@ -169,11 +169,11 @@ icmp_error_message(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, } if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) - *ctinfo += IP_CT_IS_REPLY; + ctinfo += IP_CT_IS_REPLY; /* Update skb to refer to this connection */ skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general; - skb->nfctinfo = *ctinfo; + skb->nfctinfo = ctinfo; return NF_ACCEPT; } @@ -181,7 +181,7 @@ icmp_error_message(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, static int icmp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, - enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum) + u8 pf, unsigned int hooknum) { const struct icmphdr *icmph; struct icmphdr _ih; @@ -225,7 +225,7 @@ icmp_error(struct net *net, struct nf_conn *tmpl, icmph->type != ICMP_REDIRECT) return NF_ACCEPT; - return icmp_error_message(net, tmpl, skb, ctinfo, hooknum); + return icmp_error_message(net, tmpl, skb, hooknum); } #if IS_ENABLED(CONFIG_NF_CT_NETLINK) diff --git a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c index f5a61bc3ec2b..44b9af3f813e 100644 --- a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c +++ b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c @@ -145,12 +145,12 @@ static int icmpv6_error_message(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int icmp6off, - enum ip_conntrack_info *ctinfo, unsigned int hooknum) { struct nf_conntrack_tuple intuple, origtuple; const struct nf_conntrack_tuple_hash *h; const struct nf_conntrack_l4proto *inproto; + enum ip_conntrack_info ctinfo; struct nf_conntrack_zone tmp; NF_CT_ASSERT(skb->nfct == NULL); @@ -176,7 +176,7 @@ icmpv6_error_message(struct net *net, struct nf_conn *tmpl, return -NF_ACCEPT; } - *ctinfo = IP_CT_RELATED; + ctinfo = IP_CT_RELATED; h = nf_conntrack_find_get(net, nf_ct_zone_tmpl(tmpl, skb, &tmp), &intuple); @@ -185,19 +185,19 @@ icmpv6_error_message(struct net *net, struct nf_conn *tmpl, return -NF_ACCEPT; } else { if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) - *ctinfo += IP_CT_IS_REPLY; + ctinfo += IP_CT_IS_REPLY; } /* Update skb to refer to this connection */ skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general; - skb->nfctinfo = *ctinfo; + skb->nfctinfo = ctinfo; return NF_ACCEPT; } static int icmpv6_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, - enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum) + u8 pf, unsigned int hooknum) { const struct icmp6hdr *icmp6h; struct icmp6hdr _ih; @@ -232,7 +232,7 @@ icmpv6_error(struct net *net, struct nf_conn *tmpl, if (icmp6h->icmp6_type >= 128) return NF_ACCEPT; - return icmpv6_error_message(net, tmpl, skb, dataoff, ctinfo, hooknum); + return icmpv6_error_message(net, tmpl, skb, dataoff, hooknum); } #if IS_ENABLED(CONFIG_NF_CT_NETLINK) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 3a073cd9fcf4..86186a2e2715 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1326,8 +1326,7 @@ nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum, * inverse of the return code tells to the netfilter * core what to do with the packet. */ if (l4proto->error != NULL) { - ret = l4proto->error(net, tmpl, skb, dataoff, &ctinfo, - pf, hooknum); + ret = l4proto->error(net, tmpl, skb, dataoff, pf, hooknum); if (ret <= 0) { NF_CT_STAT_INC_ATOMIC(net, error); NF_CT_STAT_INC_ATOMIC(net, invalid); diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c index b68ce6ac13b3..93dd1c5b7bff 100644 --- a/net/netfilter/nf_conntrack_proto_dccp.c +++ b/net/netfilter/nf_conntrack_proto_dccp.c @@ -561,7 +561,6 @@ static int dccp_packet(struct nf_conn *ct, const struct sk_buff *skb, static int dccp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, - enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum) { struct dccp_hdr _dh, *dh; diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 44a647418948..33279aab583d 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -508,7 +508,7 @@ static bool sctp_new(struct nf_conn *ct, const struct sk_buff *skb, } static int sctp_error(struct net *net, struct nf_conn *tpl, struct sk_buff *skb, - unsigned int dataoff, enum ip_conntrack_info *ctinfo, + unsigned int dataoff, u8 pf, unsigned int hooknum) { const struct sctphdr *sh; diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index 69f687740c76..b122e9dacfed 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -750,7 +750,6 @@ static const u8 tcp_valid_flags[(TCPHDR_FIN|TCPHDR_SYN|TCPHDR_RST|TCPHDR_ACK| static int tcp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, - enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum) { diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c index ae63944c9dc4..f6ebce6178ca 100644 --- a/net/netfilter/nf_conntrack_proto_udp.c +++ b/net/netfilter/nf_conntrack_proto_udp.c @@ -112,7 +112,6 @@ static bool udp_new(struct nf_conn *ct, const struct sk_buff *skb, static int udplite_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, - enum ip_conntrack_info *ctinfo, u8 pf, unsigned int hooknum) { unsigned int udplen = skb->len - dataoff; @@ -162,7 +161,7 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl, #endif static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, - unsigned int dataoff, enum ip_conntrack_info *ctinfo, + unsigned int dataoff, u_int8_t pf, unsigned int hooknum) { -- 2.7.3 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
