ipv6: addrconf: add per netns perturbation in inet6_addr_hash()
Bring IPv6 in par with IPv4 :
- Use net_hash_mix() to spread addresses a bit more.
- Use 256 slots hash table instead of 16
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index c1a5028..d70d981 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -950,9 +950,11 @@ ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
list_add_tail_rcu(&ifp->if_list, p);
}
-static u32 inet6_addr_hash(const struct in6_addr *addr)
+static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
{
- return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
+ u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
+
+ return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
}
static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
@@ -973,7 +975,7 @@ static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
{
- unsigned int hash = inet6_addr_hash(&ifa->addr);
+ unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
int err = 0;
spin_lock(&addrconf_hash_lock);
@@ -1838,8 +1840,8 @@ int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, int strict,
u32 banned_flags)
{
+ unsigned int hash = inet6_addr_hash(net, addr);
struct inet6_ifaddr *ifp;
- unsigned int hash = inet6_addr_hash(addr);
u32 ifp_flags;
rcu_read_lock_bh();
@@ -1917,8 +1919,8 @@ EXPORT_SYMBOL(ipv6_chk_prefix);
struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
struct net_device *dev, int strict)
{
+ unsigned int hash = inet6_addr_hash(net, addr);
struct inet6_ifaddr *ifp, *result = NULL;
- unsigned int hash = inet6_addr_hash(addr);
rcu_read_lock_bh();
hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
@@ -4242,9 +4244,9 @@ void if6_proc_exit(void)
/* Check if address is a home address configured on any interface. */
int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
{
- int ret = 0;
+ unsigned int hash = inet6_addr_hash(net, addr);
struct inet6_ifaddr *ifp = NULL;
- unsigned int hash = inet6_addr_hash(addr);
+ int ret = 0;
rcu_read_lock_bh();
hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {