tcp_metrics: Mix the network namespace into the hash function.

In preparation for using one hash table for all network namespaces
mix the network namespace into the hash value.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index 4206b14d956d..fbb42f44501e 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -252,6 +252,7 @@ static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req,
         }
 
         net = dev_net(dst->dev);
+        hash ^= net_hash_mix(net);
         hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log);
 
         for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm;
@@ -299,6 +300,7 @@ static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock
                 return NULL;
 
         net = twsk_net(tw);
+        hash ^= net_hash_mix(net);
         hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log);
 
         for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm;
@@ -347,6 +349,7 @@ static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk,
                 return NULL;
 
         net = dev_net(dst->dev);
+        hash ^= net_hash_mix(net);
         hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log);
 
         tm = __tcp_get_metrics(&saddr, &daddr, net, hash);
@@ -994,6 +997,7 @@ static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info)
         if (!reply)
                 goto nla_put_failure;
 
+        hash ^= net_hash_mix(net);
         hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log);
         ret = -ESRCH;
         rcu_read_lock();
@@ -1070,6 +1074,7 @@ static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info)
         if (ret < 0)
                 src = false;
 
+        hash ^= net_hash_mix(net);
         hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log);
         hb = net->ipv4.tcp_metrics_hash + hash;
         pp = &hb->chain;