inet: convert inet_ehash_secret and ipv6_hash_secret to net_get_random_once

Initialize the ehash and ipv6_hash_secrets with net_get_random_once.

Each compilation unit gets its own secret now:
  ipv4/inet_hashtables.o
  ipv4/udp.o
  ipv6/inet6_hashtables.o
  ipv6/udp.o
  rds/connection.o

The functions still get inlined into the hashing functions. In the fast
path we have at most two (needed in ipv6) if (unlikely(...)).

Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 27 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 4049906010f7..9433a6186f54 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -245,29 +245,6 @@ out:
 }
 EXPORT_SYMBOL(inet_listen);
 
-u32 inet_ehash_secret __read_mostly;
-EXPORT_SYMBOL(inet_ehash_secret);
-
-u32 ipv6_hash_secret __read_mostly;
-EXPORT_SYMBOL(ipv6_hash_secret);
-
-/*
- * inet_ehash_secret must be set exactly once, and to a non nul value
- * ipv6_hash_secret must be set exactly once.
- */
-void build_ehash_secret(void)
-{
-        u32 rnd;
-
-        do {
-                get_random_bytes(&rnd, sizeof(rnd));
-        } while (rnd == 0);
-
-        if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0)
-                get_random_bytes(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
-}
-EXPORT_SYMBOL(build_ehash_secret);
-
 /*
  *      Create an inet socket.
  */
@@ -284,10 +261,6 @@ static int inet_create(struct net *net, struct socket *sock, int protocol,
         int try_loading_module = 0;
         int err;
 
-        if (unlikely(!inet_ehash_secret))
-                if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
-                        build_ehash_secret();
-
         sock->state = SS_UNCONNECTED;
 
         /* Look for the requested type/protocol pair. */