1 files changed, 95 insertions, 42 deletions

diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 649bf60a9440..63d0816ab23b 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -232,30 +232,6 @@ out:
         return r;
 }
 
-#ifdef CONFIG_NET
-static int kobj_bcast_filter(struct sock *dsk, struct sk_buff *skb, void *data)
-{
-        struct kobject *kobj = data, *ksobj;
-        const struct kobj_ns_type_operations *ops;
-
-        ops = kobj_ns_ops(kobj);
-        if (!ops && kobj->kset) {
-                ksobj = &kobj->kset->kobj;
-                if (ksobj->parent != NULL)
-                        ops = kobj_ns_ops(ksobj->parent);
-        }
-
-        if (ops && ops->netlink_ns && kobj->ktype->namespace) {
-                const void *sock_ns, *ns;
-                ns = kobj->ktype->namespace(kobj);
-                sock_ns = ops->netlink_ns(dsk);
-                return sock_ns != ns;
-        }
-
-        return 0;
-}
-#endif
-
 #ifdef CONFIG_UEVENT_HELPER
 static int kobj_usermode_filter(struct kobject *kobj)
 {
@@ -327,17 +303,14 @@ static struct sk_buff *alloc_uevent_skb(struct kobj_uevent_env *env,
 
         return skb;
 }
-#endif
 
-static int kobject_uevent_net_broadcast(struct kobject *kobj,
-                                        struct kobj_uevent_env *env,
-                                        const char *action_string,
-                                        const char *devpath)
+static int uevent_net_broadcast_untagged(struct kobj_uevent_env *env,
+                                         const char *action_string,
+                                         const char *devpath)
 {
-        int retval = 0;
-#if defined(CONFIG_NET)
         struct sk_buff *skb = NULL;
         struct uevent_sock *ue_sk;
+        int retval = 0;
 
         /* send netlink message */
         list_for_each_entry(ue_sk, &uevent_sock_list, list) {
@@ -353,19 +326,93 @@ static int kobject_uevent_net_broadcast(struct kobject *kobj,
                                 continue;
                 }
 
-                retval = netlink_broadcast_filtered(uevent_sock, skb_get(skb),
-                                                    0, 1, GFP_KERNEL,
-                                                    kobj_bcast_filter,
-                                                    kobj);
+                retval = netlink_broadcast(uevent_sock, skb_get(skb), 0, 1,
+                                           GFP_KERNEL);
                 /* ENOBUFS should be handled in userspace */
                 if (retval == -ENOBUFS || retval == -ESRCH)
                         retval = 0;
         }
         consume_skb(skb);
-#endif
+
         return retval;
 }
 
+static int uevent_net_broadcast_tagged(struct sock *usk,
+                                       struct kobj_uevent_env *env,
+                                       const char *action_string,
+                                       const char *devpath)
+{
+        struct user_namespace *owning_user_ns = sock_net(usk)->user_ns;
+        struct sk_buff *skb = NULL;
+        int ret = 0;
+
+        skb = alloc_uevent_skb(env, action_string, devpath);
+        if (!skb)
+                return -ENOMEM;
+
+        /* fix credentials */
+        if (owning_user_ns != &init_user_ns) {
+                struct netlink_skb_parms *parms = &NETLINK_CB(skb);
+                kuid_t root_uid;
+                kgid_t root_gid;
+
+                /* fix uid */
+                root_uid = make_kuid(owning_user_ns, 0);
+                if (uid_valid(root_uid))
+                        parms->creds.uid = root_uid;
+
+                /* fix gid */
+                root_gid = make_kgid(owning_user_ns, 0);
+                if (gid_valid(root_gid))
+                        parms->creds.gid = root_gid;
+        }
+
+        ret = netlink_broadcast(usk, skb, 0, 1, GFP_KERNEL);
+        /* ENOBUFS should be handled in userspace */
+        if (ret == -ENOBUFS || ret == -ESRCH)
+                ret = 0;
+
+        return ret;
+}
+#endif
+
+static int kobject_uevent_net_broadcast(struct kobject *kobj,
+                                        struct kobj_uevent_env *env,
+                                        const char *action_string,
+                                        const char *devpath)
+{
+        int ret = 0;
+
+#ifdef CONFIG_NET
+        const struct kobj_ns_type_operations *ops;
+        const struct net *net = NULL;
+
+        ops = kobj_ns_ops(kobj);
+        if (!ops && kobj->kset) {
+                struct kobject *ksobj = &kobj->kset->kobj;
+                if (ksobj->parent != NULL)
+                        ops = kobj_ns_ops(ksobj->parent);
+        }
+
+        /* kobjects currently only carry network namespace tags and they
+         * are the only tag relevant here since we want to decide which
+         * network namespaces to broadcast the uevent into.
+         */
+        if (ops && ops->netlink_ns && kobj->ktype->namespace)
+                if (ops->type == KOBJ_NS_TYPE_NET)
+                        net = kobj->ktype->namespace(kobj);
+
+        if (!net)
+                ret = uevent_net_broadcast_untagged(env, action_string,
+                                                    devpath);
+        else
+                ret = uevent_net_broadcast_tagged(net->uevent_sock->sk, env,
+                                                  action_string, devpath);
+#endif
+
+        return ret;
+}
+
 static void zap_modalias_env(struct kobj_uevent_env *env)
 {
         static const char modalias_prefix[] = "MODALIAS=";
@@ -724,9 +771,13 @@ static int uevent_net_init(struct net *net)
 
         net->uevent_sock = ue_sk;
 
-        mutex_lock(&uevent_sock_mutex);
-        list_add_tail(&ue_sk->list, &uevent_sock_list);
-        mutex_unlock(&uevent_sock_mutex);
+        /* Restrict uevents to initial user namespace. */
+        if (sock_net(ue_sk->sk)->user_ns == &init_user_ns) {
+                mutex_lock(&uevent_sock_mutex);
+                list_add_tail(&ue_sk->list, &uevent_sock_list);
+                mutex_unlock(&uevent_sock_mutex);
+        }
+
         return 0;
 }
 
@@ -734,9 +785,11 @@ static void uevent_net_exit(struct net *net)
 {
         struct uevent_sock *ue_sk = net->uevent_sock;
 
-        mutex_lock(&uevent_sock_mutex);
-        list_del(&ue_sk->list);
-        mutex_unlock(&uevent_sock_mutex);
+        if (sock_net(ue_sk->sk)->user_ns == &init_user_ns) {
+                mutex_lock(&uevent_sock_mutex);
+                list_del(&ue_sk->list);
+                mutex_unlock(&uevent_sock_mutex);
+        }
 
         netlink_kernel_release(ue_sk->sk);
         kfree(ue_sk);