1 files changed, 61 insertions, 3 deletions

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 76393f2f4b22..ee57459fc258 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -23,6 +23,9 @@
 static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
 static DECLARE_RWSEM(cb_lock);
 
+atomic_t genl_sk_destructing_cnt = ATOMIC_INIT(0);
+DECLARE_WAIT_QUEUE_HEAD(genl_sk_destructing_waitq);
+
 void genl_lock(void)
 {
         mutex_lock(&genl_mutex);
@@ -435,15 +438,18 @@ int genl_unregister_family(struct genl_family *family)
 
         genl_lock_all();
 
-        genl_unregister_mc_groups(family);
-
         list_for_each_entry(rc, genl_family_chain(family->id), family_list) {
                 if (family->id != rc->id || strcmp(rc->name, family->name))
                         continue;
 
+                genl_unregister_mc_groups(family);
+
                 list_del(&rc->family_list);
                 family->n_ops = 0;
-                genl_unlock_all();
+                up_write(&cb_lock);
+                wait_event(genl_sk_destructing_waitq,
+                           atomic_read(&genl_sk_destructing_cnt) == 0);
+                genl_unlock();
 
                 kfree(family->attrbuf);
                 genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0);
@@ -983,11 +989,63 @@ static struct genl_multicast_group genl_ctrl_groups[] = {
         { .name = "notify", },
 };
 
+static int genl_bind(struct net *net, int group)
+{
+        int i, err = -ENOENT;
+
+        down_read(&cb_lock);
+        for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {
+                struct genl_family *f;
+
+                list_for_each_entry(f, genl_family_chain(i), family_list) {
+                        if (group >= f->mcgrp_offset &&
+                            group < f->mcgrp_offset + f->n_mcgrps) {
+                                int fam_grp = group - f->mcgrp_offset;
+
+                                if (!f->netnsok && net != &init_net)
+                                        err = -ENOENT;
+                                else if (f->mcast_bind)
+                                        err = f->mcast_bind(net, fam_grp);
+                                else
+                                        err = 0;
+                                break;
+                        }
+                }
+        }
+        up_read(&cb_lock);
+
+        return err;
+}
+
+static void genl_unbind(struct net *net, int group)
+{
+        int i;
+
+        down_read(&cb_lock);
+        for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {
+                struct genl_family *f;
+
+                list_for_each_entry(f, genl_family_chain(i), family_list) {
+                        if (group >= f->mcgrp_offset &&
+                            group < f->mcgrp_offset + f->n_mcgrps) {
+                                int fam_grp = group - f->mcgrp_offset;
+
+                                if (f->mcast_unbind)
+                                        f->mcast_unbind(net, fam_grp);
+                                break;
+                        }
+                }
+        }
+        up_read(&cb_lock);
+}
+
 static int __net_init genl_pernet_init(struct net *net)
 {
         struct netlink_kernel_cfg cfg = {
                 .input          = genl_rcv,
                 .flags          = NL_CFG_F_NONROOT_RECV,
+                .bind           = genl_bind,
+                .unbind         = genl_unbind,
         };
 
         /* we'll bump the group number right afterwards */