[NET]: rtnl_link: fix use-after-free

[safe/jmp/linux-2.6] / net / core / rtnetlink.c

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 416768d..fed95a3 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -35,6 +35,7 @@
 #include <linux/security.h>
 #include <linux/mutex.h>
 #include <linux/if_addr.h>
+#include <linux/nsproxy.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -74,8 +75,6 @@ void __rtnl_unlock(void)
 void rtnl_unlock(void)
 {
        mutex_unlock(&rtnl_mutex);
-       if (rtnl && rtnl->sk_receive_queue.qlen)
-               rtnl->sk_data_ready(rtnl, 0);
        netdev_run_todo();
 }
 
@@ -306,10 +305,16 @@ EXPORT_SYMBOL_GPL(rtnl_link_register);
 void __rtnl_link_unregister(struct rtnl_link_ops *ops)
 {
        struct net_device *dev, *n;
-
-       for_each_netdev_safe(dev, n) {
-               if (dev->rtnl_link_ops == ops)
-                       ops->dellink(dev);
+       struct net *net;
+
+       for_each_net(net) {
+restart:
+               for_each_netdev_safe(net, dev, n) {
+                       if (dev->rtnl_link_ops == ops) {
+                               ops->dellink(dev);
+                               goto restart;
+                       }
+               }
        }
        list_del(&ops->list);
 }
@@ -693,12 +698,13 @@ nla_put_failure:
 
 static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
+       struct net *net = skb->sk->sk_net;
        int idx;
        int s_idx = cb->args[0];
        struct net_device *dev;
 
        idx = 0;
-       for_each_netdev(dev) {
+       for_each_netdev(net, dev) {
                if (idx < s_idx)
                        goto cont;
                if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,
@@ -723,6 +729,7 @@ const struct nla_policy ifla_policy[IFLA_MAX+1] = {
        [IFLA_WEIGHT]           = { .type = NLA_U32 },
        [IFLA_OPERSTATE]        = { .type = NLA_U8 },
        [IFLA_LINKMODE]         = { .type = NLA_U8 },
+       [IFLA_NET_NS_PID]       = { .type = NLA_U32 },
 };
 
 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
@@ -730,12 +737,45 @@ static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
        [IFLA_INFO_DATA]        = { .type = NLA_NESTED },
 };
 
+static struct net *get_net_ns_by_pid(pid_t pid)
+{
+       struct task_struct *tsk;
+       struct net *net;
+
+       /* Lookup the network namespace */
+       net = ERR_PTR(-ESRCH);
+       rcu_read_lock();
+       tsk = find_task_by_vpid(pid);
+       if (tsk) {
+               struct nsproxy *nsproxy;
+               nsproxy = task_nsproxy(tsk);
+               if (nsproxy)
+                       net = get_net(nsproxy->net_ns);
+       }
+       rcu_read_unlock();
+       return net;
+}
+
 static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
                      struct nlattr **tb, char *ifname, int modified)
 {
        int send_addr_notify = 0;
        int err;
 
+       if (tb[IFLA_NET_NS_PID]) {
+               struct net *net;
+               net = get_net_ns_by_pid(nla_get_u32(tb[IFLA_NET_NS_PID]));
+               if (IS_ERR(net)) {
+                       err = PTR_ERR(net);
+                       goto errout;
+               }
+               err = dev_change_net_namespace(dev, net, ifname);
+               put_net(net);
+               if (err)
+                       goto errout;
+               modified = 1;
+       }
+
        if (tb[IFLA_MAP]) {
                struct rtnl_link_ifmap *u_map;
                struct ifmap k_map;
@@ -858,6 +898,7 @@ errout:
 
 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+       struct net *net = skb->sk->sk_net;
        struct ifinfomsg *ifm;
        struct net_device *dev;
        int err;
@@ -876,9 +917,9 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
        err = -EINVAL;
        ifm = nlmsg_data(nlh);
        if (ifm->ifi_index > 0)
-               dev = dev_get_by_index(ifm->ifi_index);
+               dev = dev_get_by_index(net, ifm->ifi_index);
        else if (tb[IFLA_IFNAME])
-               dev = dev_get_by_name(ifname);
+               dev = dev_get_by_name(net, ifname);
        else
                goto errout;
 
@@ -904,6 +945,7 @@ errout:
 
 static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+       struct net *net = skb->sk->sk_net;
        const struct rtnl_link_ops *ops;
        struct net_device *dev;
        struct ifinfomsg *ifm;
@@ -920,9 +962,9 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 
        ifm = nlmsg_data(nlh);
        if (ifm->ifi_index > 0)
-               dev = __dev_get_by_index(ifm->ifi_index);
+               dev = __dev_get_by_index(net, ifm->ifi_index);
        else if (tb[IFLA_IFNAME])
-               dev = __dev_get_by_name(ifname);
+               dev = __dev_get_by_name(net, ifname);
        else
                return -EINVAL;
 
@@ -937,7 +979,7 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
        return 0;
 }
 
-struct net_device *rtnl_create_link(char *ifname,
+struct net_device *rtnl_create_link(struct net *net, char *ifname,
                const struct rtnl_link_ops *ops, struct nlattr *tb[])
 {
        int err;
@@ -954,6 +996,7 @@ struct net_device *rtnl_create_link(char *ifname,
                        goto err_free;
        }
 
+       dev->nd_net = net;
        dev->rtnl_link_ops = ops;
 
        if (tb[IFLA_MTU])
@@ -981,6 +1024,7 @@ err:
 
 static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+       struct net *net = skb->sk->sk_net;
        const struct rtnl_link_ops *ops;
        struct net_device *dev;
        struct ifinfomsg *ifm;
@@ -1004,9 +1048,9 @@ replay:
 
        ifm = nlmsg_data(nlh);
        if (ifm->ifi_index > 0)
-               dev = __dev_get_by_index(ifm->ifi_index);
+               dev = __dev_get_by_index(net, ifm->ifi_index);
        else if (ifname[0])
-               dev = __dev_get_by_name(ifname);
+               dev = __dev_get_by_name(net, ifname);
        else
                dev = NULL;
 
@@ -1092,7 +1136,7 @@ replay:
                if (!ifname[0])
                        snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
 
-               dev = rtnl_create_link(ifname, ops, tb);
+               dev = rtnl_create_link(net, ifname, ops, tb);
 
                if (IS_ERR(dev))
                        err = PTR_ERR(dev);
@@ -1109,6 +1153,7 @@ replay:
 
 static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
+       struct net *net = skb->sk->sk_net;
        struct ifinfomsg *ifm;
        struct nlattr *tb[IFLA_MAX+1];
        struct net_device *dev = NULL;
@@ -1121,7 +1166,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 
        ifm = nlmsg_data(nlh);
        if (ifm->ifi_index > 0) {
-               dev = dev_get_by_index(ifm->ifi_index);
+               dev = dev_get_by_index(net, ifm->ifi_index);
                if (dev == NULL)
                        return -ENODEV;
        } else
@@ -1270,17 +1315,11 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
        return doit(skb, nlh, (void *)&rta_buf[0]);
 }
 
-static void rtnetlink_rcv(struct sock *sk, int len)
+static void rtnetlink_rcv(struct sk_buff *skb)
 {
-       unsigned int qlen = 0;
-
-       do {
-               mutex_lock(&rtnl_mutex);
-               netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
-               mutex_unlock(&rtnl_mutex);
-
-               netdev_run_todo();
-       } while (qlen);
+       rtnl_lock();
+       netlink_rcv_skb(skb, &rtnetlink_rcv_msg);
+       rtnl_unlock();
 }
 
 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)