Revert "netfilter: move nat hlist_head to nf_conn"

This reverts commit 7c9664351980aaa6a4b8837a314360b3a4ad382a as it is
not working properly.  Please move to 4.9 to get the full fix.

Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index 79bdfa332fb29d8e2b90f96124cfe1106904d973..de45666f96b428f8f721adbfae8f056731dbb2ed 100644 (file)
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -117,9 +117,6 @@ struct nf_conn {
        /* Extensions */
        struct nf_ct_ext *ext;
 
-#if IS_ENABLED(CONFIG_NF_NAT)
-       struct hlist_node       nat_bysource;
-#endif
        /* Storage reserved for other modules, must be the last member */
        union nf_conntrack_proto proto;
 };

diff --git a/include/net/netfilter/nf_conntrack_extend.h b/include/net/netfilter/nf_conntrack_extend.h
index 1c3035dda31f66a33d50cf2617d3a70288812383..b925395fa5ed712427fffc1f3f746fa9b1a61925 100644 (file)
--- a/include/net/netfilter/nf_conntrack_extend.h
+++ b/include/net/netfilter/nf_conntrack_extend.h
@@ -99,6 +99,9 @@ void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
 struct nf_ct_ext_type {
        /* Destroys relationships (can be NULL). */
        void (*destroy)(struct nf_conn *ct);
+       /* Called when realloacted (can be NULL).
+          Contents has already been moved. */
+       void (*move)(void *new, void *old);
 
        enum nf_ct_ext_id id;
 

diff --git a/include/net/netfilter/nf_nat.h b/include/net/netfilter/nf_nat.h
index 02515f7ed4cceceeaa9eb974531e2ec342346d07..344b1ab19220c34ec14b99b112ef3f5699a846f4 100644 (file)
--- a/include/net/netfilter/nf_nat.h
+++ b/include/net/netfilter/nf_nat.h
@@ -29,6 +29,8 @@ struct nf_conn;
 
 /* The structure embedded in the conntrack structure. */
 struct nf_conn_nat {
+       struct hlist_node bysource;
+       struct nf_conn *ct;
        union nf_conntrack_nat_help help;
 #if IS_ENABLED(CONFIG_NF_NAT_MASQUERADE_IPV4) || \
     IS_ENABLED(CONFIG_NF_NAT_MASQUERADE_IPV6)

diff --git a/net/netfilter/nf_conntrack_extend.c b/net/netfilter/nf_conntrack_extend.c
index 02bcf00c24920b332401cd7c82ab6ced951659f5..1a9545965c0d285ebe6967863865ebbcc552cb60 100644 (file)
--- a/net/netfilter/nf_conntrack_extend.c
+++ b/net/netfilter/nf_conntrack_extend.c
@@ -73,7 +73,7 @@ void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
                             size_t var_alloc_len, gfp_t gfp)
 {
        struct nf_ct_ext *old, *new;
-       int newlen, newoff;
+       int i, newlen, newoff;
        struct nf_ct_ext_type *t;
 
        /* Conntrack must not be confirmed to avoid races on reallocation. */
@@ -99,8 +99,19 @@ void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
                return NULL;
 
        if (new != old) {
+               for (i = 0; i < NF_CT_EXT_NUM; i++) {
+                       if (!__nf_ct_ext_exist(old, i))
+                               continue;
+
+                       rcu_read_lock();
+                       t = rcu_dereference(nf_ct_ext_types[i]);
+                       if (t && t->move)
+                               t->move((void *)new + new->offset[i],
+                                       (void *)old + old->offset[i]);
+                       rcu_read_unlock();
+               }
                kfree_rcu(old, rcu);
-               rcu_assign_pointer(ct->ext, new);
+               ct->ext = new;
        }
 
        new->offset[id] = newoff;

diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
index b9f466509705a72ac3a19e9d7871d368c8d012ae..4bf9b50cbb4cb4dbf0cc6e938228710627a3799c 100644 (file)
--- a/net/netfilter/nf_nat_core.c
+++ b/net/netfilter/nf_nat_core.c
@@ -198,9 +198,11 @@ find_appropriate_src(struct net *net,
                     const struct nf_nat_range *range)
 {
        unsigned int h = hash_by_src(net, tuple);
+       const struct nf_conn_nat *nat;
        const struct nf_conn *ct;
 
-       hlist_for_each_entry_rcu(ct, &nf_nat_bysource[h], nat_bysource) {
+       hlist_for_each_entry_rcu(nat, &nf_nat_bysource[h], bysource) {
+               ct = nat->ct;
                if (same_src(ct, tuple) &&
                    net_eq(net, nf_ct_net(ct)) &&
                    nf_ct_zone_equal(ct, zone, IP_CT_DIR_ORIGINAL)) {
@@ -434,7 +436,8 @@ nf_nat_setup_info(struct nf_conn *ct,
                spin_lock_bh(&nf_nat_lock);
                /* nf_conntrack_alter_reply might re-allocate extension aera */
                nat = nfct_nat(ct);
-               hlist_add_head_rcu(&ct->nat_bysource,
+               nat->ct = ct;
+               hlist_add_head_rcu(&nat->bysource,
                                   &nf_nat_bysource[srchash]);
                spin_unlock_bh(&nf_nat_lock);
        }
@@ -541,7 +544,7 @@ static int nf_nat_proto_clean(struct nf_conn *ct, void *data)
        if (nf_nat_proto_remove(ct, data))
                return 1;
 
-       if (!nat)
+       if (!nat || !nat->ct)
                return 0;
 
        /* This netns is being destroyed, and conntrack has nat null binding.
@@ -554,8 +557,9 @@ static int nf_nat_proto_clean(struct nf_conn *ct, void *data)
                return 1;
 
        spin_lock_bh(&nf_nat_lock);
-       hlist_del_rcu(&ct->nat_bysource);
+       hlist_del_rcu(&nat->bysource);
        ct->status &= ~IPS_NAT_DONE_MASK;
+       nat->ct = NULL;
        spin_unlock_bh(&nf_nat_lock);
 
        add_timer(&ct->timeout);
@@ -685,13 +689,27 @@ static void nf_nat_cleanup_conntrack(struct nf_conn *ct)
 {
        struct nf_conn_nat *nat = nf_ct_ext_find(ct, NF_CT_EXT_NAT);
 
-       if (!nat)
+       if (nat == NULL || nat->ct == NULL)
                return;
 
-       NF_CT_ASSERT(ct->status & IPS_SRC_NAT_DONE);
+       NF_CT_ASSERT(nat->ct->status & IPS_SRC_NAT_DONE);
+
+       spin_lock_bh(&nf_nat_lock);
+       hlist_del_rcu(&nat->bysource);
+       spin_unlock_bh(&nf_nat_lock);
+}
+
+static void nf_nat_move_storage(void *new, void *old)
+{
+       struct nf_conn_nat *new_nat = new;
+       struct nf_conn_nat *old_nat = old;
+       struct nf_conn *ct = old_nat->ct;
+
+       if (!ct || !(ct->status & IPS_SRC_NAT_DONE))
+               return;
 
        spin_lock_bh(&nf_nat_lock);
-       hlist_del_rcu(&ct->nat_bysource);
+       hlist_replace_rcu(&old_nat->bysource, &new_nat->bysource);
        spin_unlock_bh(&nf_nat_lock);
 }
 
@@ -699,6 +717,7 @@ static struct nf_ct_ext_type nat_extend __read_mostly = {
        .len            = sizeof(struct nf_conn_nat),
        .align          = __alignof__(struct nf_conn_nat),
        .destroy        = nf_nat_cleanup_conntrack,
+       .move           = nf_nat_move_storage,
        .id             = NF_CT_EXT_NAT,
        .flags          = NF_CT_EXT_F_PREALLOC,
 };