cipso: Relax too much careful cipso hash function.

The cipso_v4_cache is allocated to contain CIPSO_V4_CACHE_BUCKETS
buckets. The CIPSO_V4_CACHE_BUCKETS = 1 << CIPSO_V4_CACHE_BUCKETBITS,
where CIPSO_V4_CACHE_BUCKETBITS = 7.

The bucket-selection function for this hash is calculated like this:

  bkt = hash & (CIPSO_V4_CACHE_BUCKETBITS - 1);
                                     ^^^

i.e. picking only 4 buckets of possible 128 :)

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 05afb57..2c0e457 100644 (file)
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -338,7 +338,7 @@ static int cipso_v4_cache_check(const unsigned char *key,
                return -ENOENT;
 
        hash = cipso_v4_map_cache_hash(key, key_len);
-       bkt = hash & (CIPSO_V4_CACHE_BUCKETBITS - 1);
+       bkt = hash & (CIPSO_V4_CACHE_BUCKETS - 1);
        spin_lock_bh(&cipso_v4_cache[bkt].lock);
        list_for_each_entry(entry, &cipso_v4_cache[bkt].list, list) {
                if (entry->hash == hash &&
@@ -417,7 +417,7 @@ int cipso_v4_cache_add(const struct sk_buff *skb,
        atomic_inc(&secattr->cache->refcount);
        entry->lsm_data = secattr->cache;
 
-       bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETBITS - 1);
+       bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1);
        spin_lock_bh(&cipso_v4_cache[bkt].lock);
        if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
                list_add(&entry->list, &cipso_v4_cache[bkt].list);