netfilter: ipset: Log warning when a hash type of set gets full

If the set is full, the SET target cannot add more elements.
Log warning so that the admin got notified about it.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/linux/netfilter/ipset/ip_set_ahash.h b/include/linux/netfilter/ipset/ip_set_ahash.h
index b89fb79cb44fb9ed819c192776b525b243b8f895..bd1fc8d16851f7c2073565e02219a84191fcd7c8 100644 (file)
--- a/include/linux/netfilter/ipset/ip_set_ahash.h
+++ b/include/linux/netfilter/ipset/ip_set_ahash.h
@@ -353,9 +353,12 @@ retry:
        htable_bits++;
        pr_debug("attempt to resize set %s from %u to %u, t %p\n",
                 set->name, orig->htable_bits, htable_bits, orig);
-       if (!htable_bits)
+       if (!htable_bits) {
                /* In case we have plenty of memory :-) */
+               pr_warning("Cannot increase the hashsize of set %s further\n",
+                          set->name);
                return -IPSET_ERR_HASH_FULL;
+       }
        t = ip_set_alloc(sizeof(*t)
                         + jhash_size(htable_bits) * sizeof(struct hbucket));
        if (!t)
@@ -407,8 +410,12 @@ type_pf_add(struct ip_set *set, void *value, u32 timeout, u32 flags)
        int i, ret = 0;
        u32 key, multi = 0;
 
-       if (h->elements >= h->maxelem)
+       if (h->elements >= h->maxelem) {
+               if (net_ratelimit())
+                       pr_warning("Set %s is full, maxelem %u reached\n",
+                                  set->name, h->maxelem);
                return -IPSET_ERR_HASH_FULL;
+       }
 
        rcu_read_lock_bh();
        t = rcu_dereference_bh(h->table);
@@ -790,9 +797,12 @@ type_pf_tresize(struct ip_set *set, bool retried)
 retry:
        ret = 0;
        htable_bits++;
-       if (!htable_bits)
+       if (!htable_bits) {
                /* In case we have plenty of memory :-) */
+               pr_warning("Cannot increase the hashsize of set %s further\n",
+                          set->name);
                return -IPSET_ERR_HASH_FULL;
+       }
        t = ip_set_alloc(sizeof(*t)
                         + jhash_size(htable_bits) * sizeof(struct hbucket));
        if (!t)
@@ -843,8 +853,12 @@ type_pf_tadd(struct ip_set *set, void *value, u32 timeout, u32 flags)
        if (h->elements >= h->maxelem)
                /* FIXME: when set is full, we slow down here */
                type_pf_expire(h);
-       if (h->elements >= h->maxelem)
+       if (h->elements >= h->maxelem) {
+               if (net_ratelimit())
+                       pr_warning("Set %s is full, maxelem %u reached\n",
+                                  set->name, h->maxelem);
                return -IPSET_ERR_HASH_FULL;
+       }
 
        rcu_read_lock_bh();
        t = rcu_dereference_bh(h->table);