ipv6: some fixes for ipv6_dev_find()

This patch is to do 3 things for ipv6_dev_find():

  As David A. noticed,

  - rt6_lookup() is not really needed. Different from __ip_dev_find(),
    ipv6_dev_find() doesn't have a compatibility problem, so remove it.

  As Hideaki suggested,

  - "valid" (non-tentative) check for the address is also needed.
    ipv6_chk_addr() calls ipv6_chk_addr_and_flags(), which will
    traverse the address hash list, but it's heavy to be called
    inside ipv6_dev_find(). This patch is to reuse the code of
    ipv6_chk_addr_and_flags() for ipv6_dev_find().

  - dev parameter is passed into ipv6_dev_find(), as link-local
    addresses from user space has sin6_scope_id set and the dev
    lookup needs it.

Fixes: 81f6cb3122 ("ipv6: add ipv6_dev_find()")
Suggested-by: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Xin Long 2020-08-17 14:30:49 +08:00 committed by David S. Miller
parent 0410d07190
commit 4ef1a7cb08
3 changed files with 28 additions and 43 deletions

View File

@ -97,7 +97,8 @@ bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr);
struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
struct net_device *dev);
struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
const struct in6_addr *addr,

View File

@ -1893,12 +1893,13 @@ EXPORT_SYMBOL(ipv6_chk_addr);
* 2. does the address exist on the specific device
* (skip_dev_check = false)
*/
int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, bool skip_dev_check,
int strict, u32 banned_flags)
static struct net_device *
__ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, bool skip_dev_check,
int strict, u32 banned_flags)
{
unsigned int hash = inet6_addr_hash(net, addr);
const struct net_device *l3mdev;
struct net_device *l3mdev, *ndev;
struct inet6_ifaddr *ifp;
u32 ifp_flags;
@ -1909,10 +1910,11 @@ int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
dev = NULL;
hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
if (!net_eq(dev_net(ifp->idev->dev), net))
ndev = ifp->idev->dev;
if (!net_eq(dev_net(ndev), net))
continue;
if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
if (l3mdev_master_dev_rcu(ndev) != l3mdev)
continue;
/* Decouple optimistic from tentative for evaluation here.
@ -1923,15 +1925,23 @@ int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
: ifp->flags;
if (ipv6_addr_equal(&ifp->addr, addr) &&
!(ifp_flags&banned_flags) &&
(!dev || ifp->idev->dev == dev ||
(!dev || ndev == dev ||
!(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
rcu_read_unlock();
return 1;
return ndev;
}
}
rcu_read_unlock();
return 0;
return NULL;
}
int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, bool skip_dev_check,
int strict, u32 banned_flags)
{
return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
strict, banned_flags) ? 1 : 0;
}
EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
@ -1990,35 +2000,11 @@ EXPORT_SYMBOL(ipv6_chk_prefix);
*
* The caller should be protected by RCU, or RTNL.
*/
struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr)
struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
struct net_device *dev)
{
unsigned int hash = inet6_addr_hash(net, addr);
struct inet6_ifaddr *ifp, *result = NULL;
struct net_device *dev = NULL;
rcu_read_lock();
hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
if (net_eq(dev_net(ifp->idev->dev), net) &&
ipv6_addr_equal(&ifp->addr, addr)) {
result = ifp;
break;
}
}
if (!result) {
struct rt6_info *rt;
rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
if (rt) {
dev = rt->dst.dev;
ip6_rt_put(rt);
}
} else {
dev = result->idev->dev;
}
rcu_read_unlock();
return dev;
return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
IFA_F_TENTATIVE);
}
EXPORT_SYMBOL(ipv6_dev_find);

View File

@ -660,6 +660,7 @@ static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
struct udp_tunnel_sock_cfg tuncfg = {NULL};
struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
u8 node_id[NODE_ID_LEN] = {0,};
struct net_device *dev;
int rmcast = 0;
ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
@ -714,8 +715,6 @@ static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
rcu_assign_pointer(ub->bearer, b);
tipc_udp_media_addr_set(&b->addr, &local);
if (local.proto == htons(ETH_P_IP)) {
struct net_device *dev;
dev = __ip_dev_find(net, local.ipv4.s_addr, false);
if (!dev) {
err = -ENODEV;
@ -738,9 +737,8 @@ static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
b->mtu = b->media->mtu;
#if IS_ENABLED(CONFIG_IPV6)
} else if (local.proto == htons(ETH_P_IPV6)) {
struct net_device *dev;
dev = ipv6_dev_find(net, &local.ipv6);
dev = ub->ifindex ? __dev_get_by_index(net, ub->ifindex) : NULL;
dev = ipv6_dev_find(net, &local.ipv6, dev);
if (!dev) {
err = -ENODEV;
goto err;