netfilter: reduce direct skb->nfct usage
authorFlorian Westphal <fw@strlen.de>
Mon, 23 Jan 2017 17:21:55 +0000 (18:21 +0100)
committerPablo Neira Ayuso <pablo@netfilter.org>
Thu, 2 Feb 2017 13:31:52 +0000 (14:31 +0100)
Next patch makes direct skb->nfct access illegal, reduce noise
in next patch by using accessors we already have.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
include/net/ip_vs.h
net/netfilter/nf_conntrack_core.c

index cd6018a..2a344eb 100644 (file)
@@ -1554,10 +1554,13 @@ static inline void ip_vs_notrack(struct sk_buff *skb)
        struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 
        if (!ct || !nf_ct_is_untracked(ct)) {
-               nf_conntrack_put(skb->nfct);
-               skb->nfct = &nf_ct_untracked_get()->ct_general;
+               struct nf_conn *untracked;
+
+               nf_conntrack_put(&ct->ct_general);
+               untracked = nf_ct_untracked_get();
+               nf_conntrack_get(&untracked->ct_general);
+               skb->nfct = &untracked->ct_general;
                skb->nfctinfo = IP_CT_NEW;
-               nf_conntrack_get(skb->nfct);
        }
 #endif
 }
index 86186a2..adb7af3 100644 (file)
@@ -686,8 +686,11 @@ static int nf_ct_resolve_clash(struct net *net, struct sk_buff *skb,
            !nfct_nat(ct) &&
            !nf_ct_is_dying(ct) &&
            atomic_inc_not_zero(&ct->ct_general.use)) {
-               nf_ct_acct_merge(ct, ctinfo, (struct nf_conn *)skb->nfct);
-               nf_conntrack_put(skb->nfct);
+               enum ip_conntrack_info oldinfo;
+               struct nf_conn *loser_ct = nf_ct_get(skb, &oldinfo);
+
+               nf_ct_acct_merge(ct, ctinfo, loser_ct);
+               nf_conntrack_put(&loser_ct->ct_general);
                /* Assign conntrack already in hashes to this skbuff. Don't
                 * modify skb->nfctinfo to ensure consistent stateful filtering.
                 */
@@ -1288,7 +1291,7 @@ unsigned int
 nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
                struct sk_buff *skb)
 {
-       struct nf_conn *ct, *tmpl = NULL;
+       struct nf_conn *ct, *tmpl;
        enum ip_conntrack_info ctinfo;
        struct nf_conntrack_l3proto *l3proto;
        struct nf_conntrack_l4proto *l4proto;
@@ -1298,9 +1301,9 @@ nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
        int set_reply = 0;
        int ret;
 
-       if (skb->nfct) {
+       tmpl = nf_ct_get(skb, &ctinfo);
+       if (tmpl) {
                /* Previously seen (loopback or untracked)?  Ignore. */
-               tmpl = (struct nf_conn *)skb->nfct;
                if (!nf_ct_is_template(tmpl)) {
                        NF_CT_STAT_INC_ATOMIC(net, ignore);
                        return NF_ACCEPT;
@@ -1364,7 +1367,7 @@ repeat:
                /* Invalid: inverse of the return code tells
                 * the netfilter core what to do */
                pr_debug("nf_conntrack_in: Can't track with proto module\n");
-               nf_conntrack_put(skb->nfct);
+               nf_conntrack_put(&ct->ct_general);
                skb->nfct = NULL;
                NF_CT_STAT_INC_ATOMIC(net, invalid);
                if (ret == -NF_DROP)