===================================================================
@@ -92,8 +92,10 @@ extern void rtnl_link_unregister(struct
* specific netlink attributes.
* @get_link_af_size: Function to calculate size of address family specific
* netlink attributes exlusive the container attribute.
- * @parse_link_af: Function to parse a IFLA_AF_SPEC attribute and modify
- * net_device accordingly.
+ * @validate_link_af: Validate a IFLA_AF_SPEC attribute, must check attr
+ * for invalid configuration settings.
+ * @set_link_af: Function to parse a IFLA_AF_SPEC attribute and modify
+ * net_device accordingly.
*/
struct rtnl_af_ops {
struct list_head list;
@@ -103,8 +105,10 @@ struct rtnl_af_ops {
const struct net_device *dev);
size_t (*get_link_af_size)(const struct net_device *dev);
- int (*parse_link_af)(struct net_device *dev,
- const struct nlattr *attr);
+ int (*validate_link_af)(const struct net_device *dev,
+ const struct nlattr *attr);
+ int (*set_link_af)(struct net_device *dev,
+ const struct nlattr *attr);
};
extern int __rtnl_af_register(struct rtnl_af_ops *ops);
===================================================================
@@ -1107,6 +1107,28 @@ static int validate_linkmsg(struct net_d
return -EINVAL;
}
+ if (tb[IFLA_AF_SPEC]) {
+ struct nlattr *af;
+ int rem, err;
+
+ nla_for_each_nested(af, tb[IFLA_AF_SPEC], rem) {
+ const struct rtnl_af_ops *af_ops;
+
+ if (!(af_ops = rtnl_af_lookup(nla_type(af))))
+ return -EAFNOSUPPORT;
+
+ if (!af_ops->set_link_af)
+ return -EOPNOTSUPP;
+
+ if (af_ops->validate_link_af) {
+ err = af_ops->validate_link_af(dev,
+ tb[IFLA_AF_SPEC]);
+ if (err < 0)
+ return err;
+ }
+ }
+ }
+
return 0;
}
@@ -1356,12 +1378,9 @@ static int do_setlink(struct net_device
const struct rtnl_af_ops *af_ops;
if (!(af_ops = rtnl_af_lookup(nla_type(af))))
- continue;
-
- if (!af_ops->parse_link_af)
- continue;
+ BUG();
- err = af_ops->parse_link_af(dev, af);
+ err = af_ops->set_link_af(dev, af);
if (err < 0)
goto errout;
===================================================================
@@ -1289,14 +1289,14 @@ static const struct nla_policy inet_af_p
[IFLA_INET_CONF] = { .type = NLA_NESTED },
};
-static int inet_parse_link_af(struct net_device *dev, const struct nlattr *nla)
+static int inet_validate_link_af(const struct net_device *dev,
+ const struct nlattr *nla)
{
- struct in_device *in_dev = __in_dev_get_rcu(dev);
struct nlattr *a, *tb[IFLA_INET_MAX+1];
int err, rem;
- if (!in_dev)
- return -EOPNOTSUPP;
+ if (dev && !__in_dev_get_rcu(dev))
+ return -EAFNOSUPPORT;
err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy);
if (err < 0)
@@ -1314,6 +1314,21 @@ static int inet_parse_link_af(struct net
}
}
+ return 0;
+}
+
+static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla)
+{
+ struct in_device *in_dev = __in_dev_get_rcu(dev);
+ struct nlattr *a, *tb[IFLA_INET_MAX+1];
+ int rem;
+
+ if (!in_dev)
+ return -EAFNOSUPPORT;
+
+ if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0)
+ BUG();
+
if (tb[IFLA_INET_CONF]) {
nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
@@ -1689,7 +1704,8 @@ static struct rtnl_af_ops inet_af_ops =
.family = AF_INET,
.fill_link_af = inet_fill_link_af,
.get_link_af_size = inet_get_link_af_size,
- .parse_link_af = inet_parse_link_af,
+ .validate_link_af = inet_validate_link_af,
+ .set_link_af = inet_set_link_af,
};
void __init devinet_init(void)
===================================================================
@@ -3956,11 +3956,6 @@ static int inet6_fill_link_af(struct sk_
return 0;
}
-static int inet6_parse_link_af(struct net_device *dev, const struct nlattr *nla)
-{
- return -EOPNOTSUPP;
-}
-
static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
u32 pid, u32 seq, int event, unsigned int flags)
{
@@ -4670,7 +4665,6 @@ static struct rtnl_af_ops inet6_ops = {
.family = AF_INET6,
.fill_link_af = inet6_fill_link_af,
.get_link_af_size = inet6_get_link_af_size,
- .parse_link_af = inet6_parse_link_af,
};
/*
As David pointed out correctly, updates to af-specific attributes are currently not atomic. If multiple changes are requested and one of them fails, previous updates may have been applied already leaving the link behind in a undefined state. This patch splits the function parse_link_af() into two functions validate_link_af() and set_link_at(). validate_link_af() is placed to validate_linkmsg() check for errors as early as possible before any changes to the link have been made. set_link_af() is called to commit the changes later. This method is not fail proof, while it is currently sufficient to make set_link_af() inerrable and thus 100% atomic, the validation function method will not be able to detect all error scenarios in the future, there will likely always be errors depending on states which are f.e. not protected by rtnl_mutex and thus may change between validation and setting. Also, instead of silently ignoring unknown address families and config blocks for address families which did not register a set function the errors EAFNOSUPPORT respectively EOPNOSUPPORT are returned to avoid comitting 4 out of 5 update requests without notifying the user. Signed-off-by: Thomas Graf <tgraf@infradead.org> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html