1 files changed, 104 insertions, 15 deletions

diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 920a3ca6e259..70af0a7f97c0 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -18,18 +18,25 @@
 #include <linux/string.h>
 #include <linux/kobject.h>
 #include <linux/module.h>
-
+#include <linux/slab.h>
+#include <linux/user_namespace.h>
 #include <linux/socket.h>
 #include <linux/skbuff.h>
 #include <linux/netlink.h>
 #include <net/sock.h>
+#include <net/net_namespace.h>
 
 
 u64 uevent_seqnum;
 char uevent_helper[UEVENT_HELPER_PATH_LEN] = CONFIG_UEVENT_HELPER_PATH;
 static DEFINE_SPINLOCK(sequence_lock);
-#if defined(CONFIG_NET)
-static struct sock *uevent_sock;
+#ifdef CONFIG_NET
+struct uevent_sock {
+        struct list_head list;
+        struct sock *sk;
+};
+static LIST_HEAD(uevent_sock_list);
+static DEFINE_MUTEX(uevent_sock_mutex);
 #endif
 
 /* the strings here must match the enum in include/linux/kobject.h */
@@ -76,6 +83,39 @@ out:
         return ret;
 }
 
+#ifdef CONFIG_NET
+static int kobj_bcast_filter(struct sock *dsk, struct sk_buff *skb, void *data)
+{
+        struct kobject *kobj = data;
+        const struct kobj_ns_type_operations *ops;
+
+        ops = kobj_ns_ops(kobj);
+        if (ops) {
+                const void *sock_ns, *ns;
+                ns = kobj->ktype->namespace(kobj);
+                sock_ns = ops->netlink_ns(dsk);
+                return sock_ns != ns;
+        }
+
+        return 0;
+}
+#endif
+
+static int kobj_usermode_filter(struct kobject *kobj)
+{
+        const struct kobj_ns_type_operations *ops;
+
+        ops = kobj_ns_ops(kobj);
+        if (ops) {
+                const void *init_ns, *ns;
+                ns = kobj->ktype->namespace(kobj);
+                init_ns = ops->initial_ns();
+                return ns != init_ns;
+        }
+
+        return 0;
+}
+
 /**
  * kobject_uevent_env - send an uevent with environmental data
  *
@@ -83,7 +123,7 @@ out:
  * @kobj: struct kobject that the action is happening to
  * @envp_ext: pointer to environmental data
  *
- * Returns 0 if kobject_uevent() is completed with success or the
+ * Returns 0 if kobject_uevent_env() is completed with success or the
  * corresponding error when it fails.
  */
 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
@@ -95,10 +135,13 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
         const char *subsystem;
         struct kobject *top_kobj;
         struct kset *kset;
-        struct kset_uevent_ops *uevent_ops;
+        const struct kset_uevent_ops *uevent_ops;
         u64 seq;
         int i = 0;
         int retval = 0;
+#ifdef CONFIG_NET
+        struct uevent_sock *ue_sk;
+#endif
 
         pr_debug("kobject: '%s' (%p): %s\n",
                  kobject_name(kobj), kobj, __func__);
@@ -210,7 +253,9 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
 
 #if defined(CONFIG_NET)
         /* send netlink message */
-        if (uevent_sock) {
+        mutex_lock(&uevent_sock_mutex);
+        list_for_each_entry(ue_sk, &uevent_sock_list, list) {
+                struct sock *uevent_sock = ue_sk->sk;
                 struct sk_buff *skb;
                 size_t len;
 
@@ -232,18 +277,21 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
                         }
 
                         NETLINK_CB(skb).dst_group = 1;
-                        retval = netlink_broadcast(uevent_sock, skb, 0, 1,
-                                                   GFP_KERNEL);
+                        retval = netlink_broadcast_filtered(uevent_sock, skb,
+                                                            0, 1, GFP_KERNEL,
+                                                            kobj_bcast_filter,
+                                                            kobj);
                         /* ENOBUFS should be handled in userspace */
                         if (retval == -ENOBUFS)
                                 retval = 0;
                 } else
                         retval = -ENOMEM;
         }
+        mutex_unlock(&uevent_sock_mutex);
 #endif
 
         /* call uevent_helper, usually only enabled during early boot */
-        if (uevent_helper[0]) {
+        if (uevent_helper[0] && !kobj_usermode_filter(kobj)) {
                 char *argv [3];
 
                 argv [0] = uevent_helper;
@@ -269,7 +317,7 @@ exit:
 EXPORT_SYMBOL_GPL(kobject_uevent_env);
 
 /**
- * kobject_uevent - notify userspace by ending an uevent
+ * kobject_uevent - notify userspace by sending an uevent
  *
  * @action: action that is happening
  * @kobj: struct kobject that the action is happening to
@@ -319,18 +367,59 @@ int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
 EXPORT_SYMBOL_GPL(add_uevent_var);
 
 #if defined(CONFIG_NET)
-static int __init kobject_uevent_init(void)
+static int uevent_net_init(struct net *net)
 {
-        uevent_sock = netlink_kernel_create(&init_net, NETLINK_KOBJECT_UEVENT,
-                                            1, NULL, NULL, THIS_MODULE);
-        if (!uevent_sock) {
+        struct uevent_sock *ue_sk;
+
+        ue_sk = kzalloc(sizeof(*ue_sk), GFP_KERNEL);
+        if (!ue_sk)
+                return -ENOMEM;
+
+        ue_sk->sk = netlink_kernel_create(net, NETLINK_KOBJECT_UEVENT,
+                                          1, NULL, NULL, THIS_MODULE);
+        if (!ue_sk->sk) {
                 printk(KERN_ERR
                        "kobject_uevent: unable to create netlink socket!\n");
+                kfree(ue_sk);
                 return -ENODEV;
         }
-        netlink_set_nonroot(NETLINK_KOBJECT_UEVENT, NL_NONROOT_RECV);
+        mutex_lock(&uevent_sock_mutex);
+        list_add_tail(&ue_sk->list, &uevent_sock_list);
+        mutex_unlock(&uevent_sock_mutex);
         return 0;
 }
 
+static void uevent_net_exit(struct net *net)
+{
+        struct uevent_sock *ue_sk;
+
+        mutex_lock(&uevent_sock_mutex);
+        list_for_each_entry(ue_sk, &uevent_sock_list, list) {
+                if (sock_net(ue_sk->sk) == net)
+                        goto found;
+        }
+        mutex_unlock(&uevent_sock_mutex);
+        return;
+
+found:
+        list_del(&ue_sk->list);
+        mutex_unlock(&uevent_sock_mutex);
+
+        netlink_kernel_release(ue_sk->sk);
+        kfree(ue_sk);
+}
+
+static struct pernet_operations uevent_net_ops = {
+        .init   = uevent_net_init,
+        .exit   = uevent_net_exit,
+};
+
+static int __init kobject_uevent_init(void)
+{
+        netlink_set_nonroot(NETLINK_KOBJECT_UEVENT, NL_NONROOT_RECV);
+        return register_pernet_subsys(&uevent_net_ops);
+}
+
+
 postcore_initcall(kobject_uevent_init);
 #endif