netns xfrm: deal with dst entries in netns

GC is non-existent in netns, so after you hit GC threshold, no new
dst entries will be created until someone triggers cleanup in init_net.

Make xfrm4_dst_ops and xfrm6_dst_ops per-netns.
This is not done in a generic way, because it woule waste
(AF_MAX - 2) * sizeof(struct dst_ops) bytes per-netns.

Reorder GC threshold initialization so it'd be done before registering
XFRM policies.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h
index 56f8e55..74f119a 100644 (file)
--- a/include/net/netns/xfrm.h
+++ b/include/net/netns/xfrm.h
@@ -5,6 +5,7 @@
 #include <linux/wait.h>
 #include <linux/workqueue.h>
 #include <linux/xfrm.h>
+#include <net/dst_ops.h>
 
 struct ctl_table_header;
 
@@ -42,6 +43,11 @@ struct netns_xfrm {
        unsigned int            policy_count[XFRM_POLICY_MAX * 2];
        struct work_struct      policy_hash_work;
 
+       struct dst_ops          xfrm4_dst_ops;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+       struct dst_ops          xfrm6_dst_ops;
+#endif
+
        struct sock             *nlsk;
        struct sock             *nlsk_stash;
 

diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 8c08a28..67107d6 100644 (file)
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -15,7 +15,6 @@
 #include <net/xfrm.h>
 #include <net/ip.h>
 
-static struct dst_ops xfrm4_dst_ops;
 static struct xfrm_policy_afinfo xfrm4_policy_afinfo;
 
 static struct dst_entry *xfrm4_dst_lookup(struct net *net, int tos,
@@ -190,8 +189,10 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 
 static inline int xfrm4_garbage_collect(struct dst_ops *ops)
 {
-       xfrm4_policy_afinfo.garbage_collect(&init_net);
-       return (atomic_read(&xfrm4_dst_ops.entries) > xfrm4_dst_ops.gc_thresh*2);
+       struct net *net = container_of(ops, struct net, xfrm.xfrm4_dst_ops);
+
+       xfrm4_policy_afinfo.garbage_collect(net);
+       return (atomic_read(&ops->entries) > ops->gc_thresh * 2);
 }
 
 static void xfrm4_update_pmtu(struct dst_entry *dst, u32 mtu)
@@ -268,7 +269,7 @@ static struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
 static struct ctl_table xfrm4_policy_table[] = {
        {
                .procname       = "xfrm4_gc_thresh",
-               .data           = &xfrm4_dst_ops.gc_thresh,
+               .data           = &init_net.xfrm.xfrm4_dst_ops.gc_thresh,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec,
@@ -295,8 +296,6 @@ static void __exit xfrm4_policy_fini(void)
 
 void __init xfrm4_init(int rt_max_size)
 {
-       xfrm4_state_init();
-       xfrm4_policy_init();
        /*
         * Select a default value for the gc_thresh based on the main route
         * table hash size.  It seems to me the worst case scenario is when
@@ -308,6 +307,9 @@ void __init xfrm4_init(int rt_max_size)
         * and start cleaning when were 1/2 full
         */
        xfrm4_dst_ops.gc_thresh = rt_max_size/2;
+
+       xfrm4_state_init();
+       xfrm4_policy_init();
 #ifdef CONFIG_SYSCTL
        sysctl_hdr = register_net_sysctl_table(&init_net, net_ipv4_ctl_path,
                                                xfrm4_policy_table);

diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 7254e3f..dbdc696 100644 (file)
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -24,7 +24,6 @@
 #include <net/mip6.h>
 #endif
 
-static struct dst_ops xfrm6_dst_ops;
 static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
 
 static struct dst_entry *xfrm6_dst_lookup(struct net *net, int tos,
@@ -224,8 +223,10 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse)
 
 static inline int xfrm6_garbage_collect(struct dst_ops *ops)
 {
-       xfrm6_policy_afinfo.garbage_collect(&init_net);
-       return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_ops.gc_thresh*2);
+       struct net *net = container_of(ops, struct net, xfrm.xfrm6_dst_ops);
+
+       xfrm6_policy_afinfo.garbage_collect(net);
+       return (atomic_read(&ops->entries) > ops->gc_thresh * 2);
 }
 
 static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
@@ -310,7 +311,7 @@ static void xfrm6_policy_fini(void)
 static struct ctl_table xfrm6_policy_table[] = {
        {
                .procname       = "xfrm6_gc_thresh",
-               .data           = &xfrm6_dst_ops.gc_thresh,
+               .data           = &init_net.xfrm.xfrm6_dst_ops.gc_thresh,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec,
@@ -326,13 +327,6 @@ int __init xfrm6_init(void)
        int ret;
        unsigned int gc_thresh;
 
-       ret = xfrm6_policy_init();
-       if (ret)
-               goto out;
-
-       ret = xfrm6_state_init();
-       if (ret)
-               goto out_policy;
        /*
         * We need a good default value for the xfrm6 gc threshold.
         * In ipv4 we set it to the route hash table size * 8, which
@@ -346,6 +340,15 @@ int __init xfrm6_init(void)
         */
        gc_thresh = FIB6_TABLE_HASHSZ * 8;
        xfrm6_dst_ops.gc_thresh = (gc_thresh < 1024) ? 1024 : gc_thresh;
+
+       ret = xfrm6_policy_init();
+       if (ret)
+               goto out;
+
+       ret = xfrm6_state_init();
+       if (ret)
+               goto out_policy;
+
 #ifdef CONFIG_SYSCTL
        sysctl_hdr = register_net_sysctl_table(&init_net, net_ipv6_ctl_path,
                                                xfrm6_policy_table);

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index d2c8cb5..0ecb16a 100644 (file)
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1309,15 +1309,28 @@ static inline int xfrm_get_tos(struct flowi *fl, int family)
        return tos;
 }
 
-static inline struct xfrm_dst *xfrm_alloc_dst(int family)
+static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
 {
        struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+       struct dst_ops *dst_ops;
        struct xfrm_dst *xdst;
 
        if (!afinfo)
                return ERR_PTR(-EINVAL);
 
-       xdst = dst_alloc(afinfo->dst_ops) ?: ERR_PTR(-ENOBUFS);
+       switch (family) {
+       case AF_INET:
+               dst_ops = &net->xfrm.xfrm4_dst_ops;
+               break;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+       case AF_INET6:
+               dst_ops = &net->xfrm.xfrm6_dst_ops;
+               break;
+#endif
+       default:
+               BUG();
+       }
+       xdst = dst_alloc(dst_ops) ?: ERR_PTR(-ENOBUFS);
 
        xfrm_policy_put_afinfo(afinfo);
 
@@ -1366,6 +1379,7 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
                                            struct flowi *fl,
                                            struct dst_entry *dst)
 {
+       struct net *net = xp_net(policy);
        unsigned long now = jiffies;
        struct net_device *dev;
        struct dst_entry *dst_prev = NULL;
@@ -1389,7 +1403,7 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
        dst_hold(dst);
 
        for (; i < nx; i++) {
-               struct xfrm_dst *xdst = xfrm_alloc_dst(family);
+               struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
                struct dst_entry *dst1 = &xdst->u.dst;
 
                err = PTR_ERR(xdst);
@@ -2279,6 +2293,7 @@ EXPORT_SYMBOL(xfrm_bundle_ok);
 
 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 {
+       struct net *net;
        int err = 0;
        if (unlikely(afinfo == NULL))
                return -EINVAL;
@@ -2302,6 +2317,27 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
                xfrm_policy_afinfo[afinfo->family] = afinfo;
        }
        write_unlock_bh(&xfrm_policy_afinfo_lock);
+
+       rtnl_lock();
+       for_each_net(net) {
+               struct dst_ops *xfrm_dst_ops;
+
+               switch (afinfo->family) {
+               case AF_INET:
+                       xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
+                       break;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+               case AF_INET6:
+                       xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
+                       break;
+#endif
+               default:
+                       BUG();
+               }
+               *xfrm_dst_ops = *afinfo->dst_ops;
+       }
+       rtnl_unlock();
+
        return err;
 }
 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
@@ -2332,6 +2368,22 @@ int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
 
+static void __net_init xfrm_dst_ops_init(struct net *net)
+{
+       struct xfrm_policy_afinfo *afinfo;
+
+       read_lock_bh(&xfrm_policy_afinfo_lock);
+       afinfo = xfrm_policy_afinfo[AF_INET];
+       if (afinfo)
+               net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+       afinfo = xfrm_policy_afinfo[AF_INET6];
+       if (afinfo)
+               net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
+#endif
+       read_unlock_bh(&xfrm_policy_afinfo_lock);
+}
+
 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 {
        struct xfrm_policy_afinfo *afinfo;
@@ -2494,6 +2546,7 @@ static int __net_init xfrm_net_init(struct net *net)
        rv = xfrm_policy_init(net);
        if (rv < 0)
                goto out_policy;
+       xfrm_dst_ops_init(net);
        rv = xfrm_sysctl_init(net);
        if (rv < 0)
                goto out_sysctl;