[NETFILTER]: ipt_CLUSTERIP: add compat code

Adjust structure size and don't expect pointers passed in from
userspace to be valid. Also replace an enum in an ABI structure
by a fixed size type.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 22 insertions, 21 deletions

diff --git a/include/linux/netfilter_ipv4/ipt_CLUSTERIP.h b/include/linux/netfilter_ipv4/ipt_CLUSTERIP.h
index d9bceedfb3dc..daf50be22c9d 100644
--- a/include/linux/netfilter_ipv4/ipt_CLUSTERIP.h
+++ b/include/linux/netfilter_ipv4/ipt_CLUSTERIP.h
@@ -18,13 +18,13 @@ struct clusterip_config;
 struct ipt_clusterip_tgt_info {
 
         u_int32_t flags;
-        
+
         /* only relevant for new ones */
         u_int8_t clustermac[6];
         u_int16_t num_total_nodes;
         u_int16_t num_local_nodes;
         u_int16_t local_nodes[CLUSTERIP_MAX_NODES];
-        enum clusterip_hashmode hash_mode;
+        u_int32_t hash_mode;
         u_int32_t hash_initval;
 
         struct clusterip_config *config;
diff --git a/net/ipv4/netfilter/ipt_CLUSTERIP.c b/net/ipv4/netfilter/ipt_CLUSTERIP.c
index 1cef3b09c326..1981acedbfe8 100644
--- a/net/ipv4/netfilter/ipt_CLUSTERIP.c
+++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c
@@ -397,23 +397,7 @@ checkentry(const char *tablename,
         /* FIXME: further sanity checks */
 
         config = clusterip_config_find_get(e->ip.dst.s_addr, 1);
-        if (config) {
-                if (cipinfo->config != NULL) {
-                        /* Case A: This is an entry that gets reloaded, since
-                         * it still has a cipinfo->config pointer. Simply
-                         * increase the entry refcount and return */
-                        if (cipinfo->config != config) {
-                                printk(KERN_ERR "CLUSTERIP: Reloaded entry "
-                                       "has invalid config pointer!\n");
-                                return false;
-                        }
-                } else {
-                        /* Case B: This is a new rule referring to an existing
-                         * clusterip config. */
-                        cipinfo->config = config;
-                }
-        } else {
-                /* Case C: This is a completely new clusterip config */
+        if (!config) {
                 if (!(cipinfo->flags & CLUSTERIP_FLAG_NEW)) {
                         printk(KERN_WARNING "CLUSTERIP: no config found for %u.%u.%u.%u, need 'new'\n", NIPQUAD(e->ip.dst.s_addr));
                         return false;
@@ -440,8 +424,8 @@ checkentry(const char *tablename,
                         }
                         dev_mc_add(config->dev,config->clustermac, ETH_ALEN, 0);
                 }
-                cipinfo->config = config;
         }
+        cipinfo->config = config;
 
         if (nf_ct_l3proto_try_module_get(target->family) < 0) {
                 printk(KERN_WARNING "can't load conntrack support for "
@@ -466,13 +450,30 @@ static void destroy(const struct xt_target *target, void *targinfo)
         nf_ct_l3proto_module_put(target->family);
 }
 
+#ifdef CONFIG_COMPAT
+struct compat_ipt_clusterip_tgt_info
+{
+        u_int32_t       flags;
+        u_int8_t        clustermac[6];
+        u_int16_t       num_total_nodes;
+        u_int16_t       num_local_nodes;
+        u_int16_t       local_nodes[CLUSTERIP_MAX_NODES];
+        u_int32_t       hash_mode;
+        u_int32_t       hash_initval;
+        compat_uptr_t   config;
+};
+#endif /* CONFIG_COMPAT */
+
 static struct xt_target clusterip_tgt __read_mostly = {
         .name           = "CLUSTERIP",
         .family         = AF_INET,
         .target         = target,
-        .targetsize     = sizeof(struct ipt_clusterip_tgt_info),
         .checkentry     = checkentry,
         .destroy        = destroy,
+        .targetsize     = sizeof(struct ipt_clusterip_tgt_info),
+#ifdef CONFIG_COMPAT
+        .compatsize     = sizeof(struct compat_ipt_clusterip_tgt_info),
+#endif /* CONFIG_COMPAT */
         .me             = THIS_MODULE
 };