netfilter: nf_conncount: Fix garbage collection with zones
authorYi-Hung Wei <yihung.wei@gmail.com>
Tue, 12 Jun 2018 17:51:34 +0000 (10:51 -0700)
committerPablo Neira Ayuso <pablo@netfilter.org>
Tue, 12 Jun 2018 18:07:07 +0000 (20:07 +0200)
Currently, we use check_hlist() for garbage colleciton. However, we
use the ‘zone’ from the counted entry to query the existence of
existing entries in the hlist. This could be wrong when they are in
different zones, and this patch fixes this issue.

Fixes: e59ea3df3fc2 ("netfilter: xt_connlimit: honor conntrack zone if available")
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
include/net/netfilter/nf_conntrack_count.h
net/netfilter/nf_conncount.c
net/netfilter/nft_connlimit.c

index 1910b657243027e3faf36dde94af7ac1b29a0843..3a188a0923a38189f010ebf7d99766d1bd6cea54 100644 (file)
@@ -20,7 +20,8 @@ unsigned int nf_conncount_lookup(struct net *net, struct hlist_head *head,
                                 bool *addit);
 
 bool nf_conncount_add(struct hlist_head *head,
-                     const struct nf_conntrack_tuple *tuple);
+                     const struct nf_conntrack_tuple *tuple,
+                     const struct nf_conntrack_zone *zone);
 
 void nf_conncount_cache_free(struct hlist_head *hhead);
 
index 3b5059a8dcdd19d1aadaf10e5600cb65491c812c..d8383609fe2825b707cfb8ebc54381761ccc1108 100644 (file)
@@ -46,6 +46,7 @@
 struct nf_conncount_tuple {
        struct hlist_node               node;
        struct nf_conntrack_tuple       tuple;
+       struct nf_conntrack_zone        zone;
 };
 
 struct nf_conncount_rb {
@@ -80,7 +81,8 @@ static int key_diff(const u32 *a, const u32 *b, unsigned int klen)
 }
 
 bool nf_conncount_add(struct hlist_head *head,
-                     const struct nf_conntrack_tuple *tuple)
+                     const struct nf_conntrack_tuple *tuple,
+                     const struct nf_conntrack_zone *zone)
 {
        struct nf_conncount_tuple *conn;
 
@@ -88,6 +90,7 @@ bool nf_conncount_add(struct hlist_head *head,
        if (conn == NULL)
                return false;
        conn->tuple = *tuple;
+       conn->zone = *zone;
        hlist_add_head(&conn->node, head);
        return true;
 }
@@ -108,7 +111,7 @@ unsigned int nf_conncount_lookup(struct net *net, struct hlist_head *head,
 
        /* check the saved connections */
        hlist_for_each_entry_safe(conn, n, head, node) {
-               found = nf_conntrack_find_get(net, zone, &conn->tuple);
+               found = nf_conntrack_find_get(net, &conn->zone, &conn->tuple);
                if (found == NULL) {
                        hlist_del(&conn->node);
                        kmem_cache_free(conncount_conn_cachep, conn);
@@ -117,7 +120,8 @@ unsigned int nf_conncount_lookup(struct net *net, struct hlist_head *head,
 
                found_ct = nf_ct_tuplehash_to_ctrack(found);
 
-               if (tuple && nf_ct_tuple_equal(&conn->tuple, tuple)) {
+               if (tuple && nf_ct_tuple_equal(&conn->tuple, tuple) &&
+                   nf_ct_zone_equal(found_ct, zone, zone->dir)) {
                        /*
                         * Just to be sure we have it only once in the list.
                         * We should not see tuples twice unless someone hooks
@@ -196,7 +200,7 @@ count_tree(struct net *net, struct rb_root *root,
                        if (!addit)
                                return count;
 
-                       if (!nf_conncount_add(&rbconn->hhead, tuple))
+                       if (!nf_conncount_add(&rbconn->hhead, tuple, zone))
                                return 0; /* hotdrop */
 
                        return count + 1;
@@ -238,6 +242,7 @@ count_tree(struct net *net, struct rb_root *root,
        }
 
        conn->tuple = *tuple;
+       conn->zone = *zone;
        memcpy(rbconn->key, key, sizeof(u32) * keylen);
 
        INIT_HLIST_HEAD(&rbconn->hhead);
index 50c068d660e54647c0068c087a9f6b90f9e14686..a832c59f0a9cbeb30cd1d261c2be81fc8b5d7027 100644 (file)
@@ -52,7 +52,7 @@ static inline void nft_connlimit_do_eval(struct nft_connlimit *priv,
        if (!addit)
                goto out;
 
-       if (!nf_conncount_add(&priv->hhead, tuple_ptr)) {
+       if (!nf_conncount_add(&priv->hhead, tuple_ptr, zone)) {
                regs->verdict.code = NF_DROP;
                spin_unlock_bh(&priv->lock);
                return;