From 9976fc6e6edbb0372f084a2ae8c1b8103b3bff1d Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 12 Sep 2018 15:19:08 +0200 Subject: netfilter: conntrack: remove the l4proto->new() function ->new() gets invoked after ->error() and before ->packet() if a conntrack lookup has found no result for the tuple. We can fold it into ->packet() -- the packet() implementations can check if the conntrack is confirmed (new) or not (already in hash). If its unconfirmed, the conntrack isn't in the hash yet so current skb created a new conntrack entry. Only relevant side effect -- if packet() doesn't return NF_ACCEPT but -NF_ACCEPT (or drop), while the conntrack was just created, then the newly allocated conntrack is freed right away, rather than not created in the first place. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_proto_dccp.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'net/netfilter/nf_conntrack_proto_dccp.c') diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c index 8595c79742a2..e7b5449ea883 100644 --- a/net/netfilter/nf_conntrack_proto_dccp.c +++ b/net/netfilter/nf_conntrack_proto_dccp.c @@ -389,18 +389,15 @@ static inline struct nf_dccp_net *dccp_pernet(struct net *net) return &net->ct.nf_ct_proto.dccp; } -static bool dccp_new(struct nf_conn *ct, const struct sk_buff *skb, - unsigned int dataoff) +static noinline bool +dccp_new(struct nf_conn *ct, const struct sk_buff *skb, + const struct dccp_hdr *dh) { struct net *net = nf_ct_net(ct); struct nf_dccp_net *dn; - struct dccp_hdr _dh, *dh; const char *msg; u_int8_t state; - dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh); - BUG_ON(dh == NULL); - state = dccp_state_table[CT_DCCP_ROLE_CLIENT][dh->dccph_type][CT_DCCP_NONE]; switch (state) { default: @@ -449,8 +446,12 @@ static int dccp_packet(struct nf_conn *ct, const struct sk_buff *skb, unsigned int *timeouts; dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh); - BUG_ON(dh == NULL); + if (!dh) + return NF_DROP; + type = dh->dccph_type; + if (!nf_ct_is_confirmed(ct) && !dccp_new(ct, skb, dh)) + return -NF_ACCEPT; if (type == DCCP_PKT_RESET && !test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { @@ -850,7 +851,6 @@ static struct nf_proto_net *dccp_get_net_proto(struct net *net) const struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp4 = { .l3proto = AF_INET, .l4proto = IPPROTO_DCCP, - .new = dccp_new, .packet = dccp_packet, .error = dccp_error, .can_early_drop = dccp_can_early_drop, @@ -883,7 +883,6 @@ EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_dccp4); const struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp6 = { .l3proto = AF_INET6, .l4proto = IPPROTO_DCCP, - .new = dccp_new, .packet = dccp_packet, .error = dccp_error, .can_early_drop = dccp_can_early_drop, -- cgit