ipv6: add a new namespace for nf_conntrack_reasm

As pointed by Michal, it is necessary to add a new
namespace for nf_conntrack_reasm code, this prepares
for the second patch.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Michal Kubeček <mkubecek@suse.cz>
Cc: David Miller <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 5ae57f1ab7551e556c0145dcb51206d5de08ecc6..d61e2b36d9e32227f36dc9b4d935a05e554c7478 100644 (file)
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -92,6 +92,9 @@ struct net {
        struct netns_xt         xt;
 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
        struct netns_ct         ct;
+#endif
+#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
+       struct netns_nf_frag    nf_frag;
 #endif
        struct sock             *nfnl;
        struct sock             *nfnl_stash;

diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h
index 0318104a945849f21a34786a5f4fd642a9995e10..214cb0a53359e03b476670e49eb73298545e1859 100644 (file)
--- a/include/net/netns/ipv6.h
+++ b/include/net/netns/ipv6.h
@@ -71,4 +71,12 @@ struct netns_ipv6 {
 #endif
 #endif
 };
+
+#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
+struct netns_nf_frag {
+       struct netns_sysctl_ipv6 sysctl;
+       struct netns_frags      frags;
+};
+#endif
+
 #endif

diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index f94fb3ac2a799e2350c940719d2aadee43ac5550..f40f327ccc0c026c73bd9968cb739823f07dac07 100644 (file)
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -71,27 +71,26 @@ struct nf_ct_frag6_queue
 };
 
 static struct inet_frags nf_frags;
-static struct netns_frags nf_init_frags;
 
 #ifdef CONFIG_SYSCTL
 static struct ctl_table nf_ct_frag6_sysctl_table[] = {
        {
                .procname       = "nf_conntrack_frag6_timeout",
-               .data           = &nf_init_frags.timeout,
+               .data           = &init_net.nf_frag.frags.timeout,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_jiffies,
        },
        {
                .procname       = "nf_conntrack_frag6_low_thresh",
-               .data           = &nf_init_frags.low_thresh,
+               .data           = &init_net.nf_frag.frags.low_thresh,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec,
        },
        {
                .procname       = "nf_conntrack_frag6_high_thresh",
-               .data           = &nf_init_frags.high_thresh,
+               .data           = &init_net.nf_frag.frags.high_thresh,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec,
@@ -99,7 +98,55 @@ static struct ctl_table nf_ct_frag6_sysctl_table[] = {
        { }
 };
 
-static struct ctl_table_header *nf_ct_frag6_sysctl_header;
+static int __net_init nf_ct_frag6_sysctl_register(struct net *net)
+{
+       struct ctl_table *table;
+       struct ctl_table_header *hdr;
+
+       table = nf_ct_frag6_sysctl_table;
+       if (!net_eq(net, &init_net)) {
+               table = kmemdup(table, sizeof(nf_ct_frag6_sysctl_table),
+                               GFP_KERNEL);
+               if (table == NULL)
+                       goto err_alloc;
+
+               table[0].data = &net->ipv6.frags.high_thresh;
+               table[1].data = &net->ipv6.frags.low_thresh;
+               table[2].data = &net->ipv6.frags.timeout;
+       }
+
+       hdr = register_net_sysctl(net, "net/netfilter", table);
+       if (hdr == NULL)
+               goto err_reg;
+
+       net->ipv6.sysctl.frags_hdr = hdr;
+       return 0;
+
+err_reg:
+       if (!net_eq(net, &init_net))
+               kfree(table);
+err_alloc:
+       return -ENOMEM;
+}
+
+static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
+{
+       struct ctl_table *table;
+
+       table = net->nf_frag.sysctl.frags_hdr->ctl_table_arg;
+       unregister_net_sysctl_table(net->nf_frag.sysctl.frags_hdr);
+       if (!net_eq(net, &init_net))
+               kfree(table);
+}
+
+#else
+static int __net_init nf_ct_frag6_sysctl_register(struct net *net)
+{
+       return 0;
+}
+static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net)
+{
+}
 #endif
 
 static unsigned int nf_hashfn(struct inet_frag_queue *q)
@@ -131,13 +178,6 @@ static __inline__ void fq_kill(struct nf_ct_frag6_queue *fq)
        inet_frag_kill(&fq->q, &nf_frags);
 }
 
-static void nf_ct_frag6_evictor(void)
-{
-       local_bh_disable();
-       inet_frag_evictor(&nf_init_frags, &nf_frags);
-       local_bh_enable();
-}
-
 static void nf_ct_frag6_expire(unsigned long data)
 {
        struct nf_ct_frag6_queue *fq;
@@ -158,9 +198,9 @@ out:
 }
 
 /* Creation primitives. */
-
-static __inline__ struct nf_ct_frag6_queue *
-fq_find(__be32 id, u32 user, struct in6_addr *src, struct in6_addr *dst)
+static inline struct nf_ct_frag6_queue *fq_find(struct net *net, __be32 id,
+                                               u32 user, struct in6_addr *src,
+                                               struct in6_addr *dst)
 {
        struct inet_frag_queue *q;
        struct ip6_create_arg arg;
@@ -174,7 +214,7 @@ fq_find(__be32 id, u32 user, struct in6_addr *src, struct in6_addr *dst)
        read_lock_bh(&nf_frags.lock);
        hash = inet6_hash_frag(id, src, dst, nf_frags.rnd);
 
-       q = inet_frag_find(&nf_init_frags, &nf_frags, &arg, hash);
+       q = inet_frag_find(&net->nf_frag.frags, &nf_frags, &arg, hash);
        local_bh_enable();
        if (q == NULL)
                goto oom;
@@ -312,7 +352,7 @@ found:
        fq->q.meat += skb->len;
        if (payload_len > fq->q.max_size)
                fq->q.max_size = payload_len;
-       atomic_add(skb->truesize, &nf_init_frags.mem);
+       atomic_add(skb->truesize, &fq->q.net->mem);
 
        /* The first fragment.
         * nhoffset is obtained from the first fragment, of course.
@@ -322,7 +362,7 @@ found:
                fq->q.last_in |= INET_FRAG_FIRST_IN;
        }
        write_lock(&nf_frags.lock);
-       list_move_tail(&fq->q.lru_list, &nf_init_frags.lru_list);
+       list_move_tail(&fq->q.lru_list, &fq->q.net->lru_list);
        write_unlock(&nf_frags.lock);
        return 0;
 
@@ -391,7 +431,7 @@ nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
                clone->ip_summed = head->ip_summed;
 
                NFCT_FRAG6_CB(clone)->orig = NULL;
-               atomic_add(clone->truesize, &nf_init_frags.mem);
+               atomic_add(clone->truesize, &fq->q.net->mem);
        }
 
        /* We have to remove fragment header from datagram and to relocate
@@ -415,7 +455,7 @@ nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
                        head->csum = csum_add(head->csum, fp->csum);
                head->truesize += fp->truesize;
        }
-       atomic_sub(head->truesize, &nf_init_frags.mem);
+       atomic_sub(head->truesize, &fq->q.net->mem);
 
        head->local_df = 1;
        head->next = NULL;
@@ -527,6 +567,8 @@ struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user)
 {
        struct sk_buff *clone;
        struct net_device *dev = skb->dev;
+       struct net *net = skb_dst(skb) ? dev_net(skb_dst(skb)->dev)
+                                      : dev_net(skb->dev);
        struct frag_hdr *fhdr;
        struct nf_ct_frag6_queue *fq;
        struct ipv6hdr *hdr;
@@ -560,10 +602,13 @@ struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user)
        hdr = ipv6_hdr(clone);
        fhdr = (struct frag_hdr *)skb_transport_header(clone);
 
-       if (atomic_read(&nf_init_frags.mem) > nf_init_frags.high_thresh)
-               nf_ct_frag6_evictor();
+       if (atomic_read(&net->nf_frag.frags.mem) > net->nf_frag.frags.high_thresh) {
+               local_bh_disable();
+               inet_frag_evictor(&net->nf_frag.frags, &nf_frags);
+               local_bh_enable();
+       }
 
-       fq = fq_find(fhdr->identification, user, &hdr->saddr, &hdr->daddr);
+       fq = fq_find(net, fhdr->identification, user, &hdr->saddr, &hdr->daddr);
        if (fq == NULL) {
                pr_debug("Can't find and can't create new queue\n");
                goto ret_orig;
@@ -621,8 +666,31 @@ void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
        nf_conntrack_put_reasm(skb);
 }
 
+static int nf_ct_net_init(struct net *net)
+{
+       net->nf_frag.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
+       net->nf_frag.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
+       net->nf_frag.frags.timeout = IPV6_FRAG_TIMEOUT;
+       inet_frags_init_net(&net->nf_frag.frags);
+
+       return nf_ct_frag6_sysctl_register(net);
+}
+
+static void nf_ct_net_exit(struct net *net)
+{
+       nf_ct_frags6_sysctl_unregister(net);
+       inet_frags_exit_net(&net->nf_frag.frags, &nf_frags);
+}
+
+static struct pernet_operations nf_ct_net_ops = {
+       .init = nf_ct_net_init,
+       .exit = nf_ct_net_exit,
+};
+
 int nf_ct_frag6_init(void)
 {
+       int ret = 0;
+
        nf_frags.hashfn = nf_hashfn;
        nf_frags.constructor = ip6_frag_init;
        nf_frags.destructor = NULL;
@@ -631,32 +699,17 @@ int nf_ct_frag6_init(void)
        nf_frags.match = ip6_frag_match;
        nf_frags.frag_expire = nf_ct_frag6_expire;
        nf_frags.secret_interval = 10 * 60 * HZ;
-       nf_init_frags.timeout = IPV6_FRAG_TIMEOUT;
-       nf_init_frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
-       nf_init_frags.low_thresh = IPV6_FRAG_LOW_THRESH;
-       inet_frags_init_net(&nf_init_frags);
        inet_frags_init(&nf_frags);
 
-#ifdef CONFIG_SYSCTL
-       nf_ct_frag6_sysctl_header = register_net_sysctl(&init_net, "net/netfilter",
-                                                       nf_ct_frag6_sysctl_table);
-       if (!nf_ct_frag6_sysctl_header) {
+       ret = register_pernet_subsys(&nf_ct_net_ops);
+       if (ret)
                inet_frags_fini(&nf_frags);
-               return -ENOMEM;
-       }
-#endif
 
-       return 0;
+       return ret;
 }
 
 void nf_ct_frag6_cleanup(void)
 {
-#ifdef CONFIG_SYSCTL
-       unregister_net_sysctl_table(nf_ct_frag6_sysctl_header);
-       nf_ct_frag6_sysctl_header = NULL;
-#endif
+       unregister_pernet_subsys(&nf_ct_net_ops);
        inet_frags_fini(&nf_frags);
-
-       nf_init_frags.low_thresh = 0;
-       nf_ct_frag6_evictor();
 }