1 files changed, 163 insertions, 62 deletions

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index eed4c6a8afc0..d07ecda0a92d 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -18,8 +18,6 @@
 #include <net/sock.h>
 #include <net/genetlink.h>
 
-struct sock *genl_sock = NULL;
-
 static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
 
 static inline void genl_lock(void)
@@ -99,25 +97,17 @@ static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family)
 */
 static inline u16 genl_generate_id(void)
 {
-        static u16 id_gen_idx;
-        int overflowed = 0;
+        static u16 id_gen_idx = GENL_MIN_ID;
+        int i;
 
-        do {
-                if (id_gen_idx == 0)
+        for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) {
+                if (!genl_family_find_byid(id_gen_idx))
+                        return id_gen_idx;
+                if (++id_gen_idx > GENL_MAX_ID)
                         id_gen_idx = GENL_MIN_ID;
+        }
 
-                if (++id_gen_idx > GENL_MAX_ID) {
-                        if (!overflowed) {
-                                overflowed = 1;
-                                id_gen_idx = 0;
-                                continue;
-                        } else
-                                return 0;
-                }
-
-        } while (genl_family_find_byid(id_gen_idx));
-
-        return id_gen_idx;
+        return 0;
 }
 
 static struct genl_multicast_group notify_grp;
@@ -138,7 +128,7 @@ int genl_register_mc_group(struct genl_family *family,
 {
         int id;
         unsigned long *new_groups;
-        int err;
+        int err = 0;
 
         BUG_ON(grp->name[0] == '\0');
 
@@ -175,10 +165,34 @@ int genl_register_mc_group(struct genl_family *family,
                 mc_groups_longs++;
         }
 
-        err = netlink_change_ngroups(genl_sock,
-                                     mc_groups_longs * BITS_PER_LONG);
-        if (err)
-                goto out;
+        if (family->netnsok) {
+                struct net *net;
+
+                netlink_table_grab();
+                rcu_read_lock();
+                for_each_net_rcu(net) {
+                        err = __netlink_change_ngroups(net->genl_sock,
+                                        mc_groups_longs * BITS_PER_LONG);
+                        if (err) {
+                                /*
+                                 * No need to roll back, can only fail if
+                                 * memory allocation fails and then the
+                                 * number of _possible_ groups has been
+                                 * increased on some sockets which is ok.
+                                 */
+                                rcu_read_unlock();
+                                netlink_table_ungrab();
+                                goto out;
+                        }
+                }
+                rcu_read_unlock();
+                netlink_table_ungrab();
+        } else {
+                err = netlink_change_ngroups(init_net.genl_sock,
+                                             mc_groups_longs * BITS_PER_LONG);
+                if (err)
+                        goto out;
+        }
 
         grp->id = id;
         set_bit(id, mc_groups);
@@ -195,8 +209,16 @@ EXPORT_SYMBOL(genl_register_mc_group);
 static void __genl_unregister_mc_group(struct genl_family *family,
                                        struct genl_multicast_group *grp)
 {
+        struct net *net;
         BUG_ON(grp->family != family);
-        netlink_clear_multicast_users(genl_sock, grp->id);
+
+        netlink_table_grab();
+        rcu_read_lock();
+        for_each_net_rcu(net)
+                __netlink_clear_multicast_users(net->genl_sock, grp->id);
+        rcu_read_unlock();
+        netlink_table_ungrab();
+
         clear_bit(grp->id, mc_groups);
         list_del(&grp->list);
         genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp);
@@ -344,11 +366,6 @@ int genl_register_family(struct genl_family *family)
                 goto errout_locked;
         }
 
-        if (genl_family_find_byid(family->id)) {
-                err = -EEXIST;
-                goto errout_locked;
-        }
-
         if (family->id == GENL_ID_GENERATE) {
                 u16 newid = genl_generate_id();
 
@@ -358,6 +375,9 @@ int genl_register_family(struct genl_family *family)
                 }
 
                 family->id = newid;
+        } else if (genl_family_find_byid(family->id)) {
+                err = -EEXIST;
+                goto errout_locked;
         }
 
         if (family->maxattr) {
@@ -467,6 +487,7 @@ static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
         struct genl_ops *ops;
         struct genl_family *family;
+        struct net *net = sock_net(skb->sk);
         struct genl_info info;
         struct genlmsghdr *hdr = nlmsg_data(nlh);
         int hdrlen, err;
@@ -475,6 +496,10 @@ static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
         if (family == NULL)
                 return -ENOENT;
 
+        /* this family doesn't exist in this netns */
+        if (!family->netnsok && !net_eq(net, &init_net))
+                return -ENOENT;
+
         hdrlen = GENL_HDRLEN + family->hdrsize;
         if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
                 return -EINVAL;
@@ -492,7 +517,7 @@ static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                         return -EOPNOTSUPP;
 
                 genl_unlock();
-                err = netlink_dump_start(genl_sock, skb, nlh,
+                err = netlink_dump_start(net->genl_sock, skb, nlh,
                                          ops->dumpit, ops->done);
                 genl_lock();
                 return err;
@@ -514,6 +539,7 @@ static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
         info.genlhdr = nlmsg_data(nlh);
         info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;
         info.attrs = family->attrbuf;
+        genl_info_net_set(&info, net);
 
         return ops->doit(skb, &info);
 }
@@ -534,6 +560,7 @@ static struct genl_family genl_ctrl = {
         .name = "nlctrl",
         .version = 0x2,
         .maxattr = CTRL_ATTR_MAX,
+        .netnsok = true,
 };
 
 static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq,
@@ -650,6 +677,7 @@ static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb)
 
         int i, n = 0;
         struct genl_family *rt;
+        struct net *net = sock_net(skb->sk);
         int chains_to_skip = cb->args[0];
         int fams_to_skip = cb->args[1];
 
@@ -658,6 +686,8 @@ static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb)
                         continue;
                 n = 0;
                 list_for_each_entry(rt, genl_family_chain(i), family_list) {
+                        if (!rt->netnsok && !net_eq(net, &init_net))
+                                continue;
                         if (++n < fams_to_skip)
                                 continue;
                         if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid,
@@ -729,6 +759,7 @@ static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info)
         if (info->attrs[CTRL_ATTR_FAMILY_ID]) {
                 u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]);
                 res = genl_family_find_byid(id);
+                err = -ENOENT;
         }
 
         if (info->attrs[CTRL_ATTR_FAMILY_NAME]) {
@@ -736,49 +767,61 @@ static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info)
 
                 name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]);
                 res = genl_family_find_byname(name);
+                err = -ENOENT;
         }
 
-        if (res == NULL) {
-                err = -ENOENT;
-                goto errout;
+        if (res == NULL)
+                return err;
+
+        if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) {
+                /* family doesn't exist here */
+                return -ENOENT;
         }
 
         msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq,
                                     CTRL_CMD_NEWFAMILY);
-        if (IS_ERR(msg)) {
-                err = PTR_ERR(msg);
-                goto errout;
-        }
+        if (IS_ERR(msg))
+                return PTR_ERR(msg);
 
-        err = genlmsg_reply(msg, info);
-errout:
-        return err;
+        return genlmsg_reply(msg, info);
 }
 
 static int genl_ctrl_event(int event, void *data)
 {
         struct sk_buff *msg;
+        struct genl_family *family;
+        struct genl_multicast_group *grp;
 
-        if (genl_sock == NULL)
+        /* genl is still initialising */
+        if (!init_net.genl_sock)
                 return 0;
 
         switch (event) {
         case CTRL_CMD_NEWFAMILY:
         case CTRL_CMD_DELFAMILY:
-                msg = ctrl_build_family_msg(data, 0, 0, event);
-                if (IS_ERR(msg))
-                        return PTR_ERR(msg);
-
-                genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL);
+                family = data;
+                msg = ctrl_build_family_msg(family, 0, 0, event);
                 break;
         case CTRL_CMD_NEWMCAST_GRP:
         case CTRL_CMD_DELMCAST_GRP:
+                grp = data;
+                family = grp->family;
                 msg = ctrl_build_mcgrp_msg(data, 0, 0, event);
-                if (IS_ERR(msg))
-                        return PTR_ERR(msg);
-
-                genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL);
                 break;
+        default:
+                return -EINVAL;
+        }
+
+        if (IS_ERR(msg))
+                return PTR_ERR(msg);
+
+        if (!family->netnsok) {
+                genlmsg_multicast_netns(&init_net, msg, 0,
+                                        GENL_ID_CTRL, GFP_KERNEL);
+        } else {
+                rcu_read_lock();
+                genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC);
+                rcu_read_unlock();
         }
 
         return 0;
@@ -795,6 +838,33 @@ static struct genl_multicast_group notify_grp = {
         .name           = "notify",
 };
 
+static int __net_init genl_pernet_init(struct net *net)
+{
+        /* we'll bump the group number right afterwards */
+        net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, 0,
+                                               genl_rcv, &genl_mutex,
+                                               THIS_MODULE);
+
+        if (!net->genl_sock && net_eq(net, &init_net))
+                panic("GENL: Cannot initialize generic netlink\n");
+
+        if (!net->genl_sock)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static void __net_exit genl_pernet_exit(struct net *net)
+{
+        netlink_kernel_release(net->genl_sock);
+        net->genl_sock = NULL;
+}
+
+static struct pernet_operations genl_pernet_ops = {
+        .init = genl_pernet_init,
+        .exit = genl_pernet_exit,
+};
+
 static int __init genl_init(void)
 {
         int i, err;
@@ -804,36 +874,67 @@ static int __init genl_init(void)
 
         err = genl_register_family(&genl_ctrl);
         if (err < 0)
-                goto errout;
+                goto problem;
 
         err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops);
         if (err < 0)
-                goto errout_register;
+                goto problem;
 
         netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV);
 
-        /* we'll bump the group number right afterwards */
-        genl_sock = netlink_kernel_create(&init_net, NETLINK_GENERIC, 0,
-                                          genl_rcv, &genl_mutex, THIS_MODULE);
-        if (genl_sock == NULL)
-                panic("GENL: Cannot initialize generic netlink\n");
+        err = register_pernet_subsys(&genl_pernet_ops);
+        if (err)
+                goto problem;
 
         err = genl_register_mc_group(&genl_ctrl, &notify_grp);
         if (err < 0)
-                goto errout_register;
+                goto problem;
 
         return 0;
 
-errout_register:
-        genl_unregister_family(&genl_ctrl);
-errout:
+problem:
         panic("GENL: Cannot register controller: %d\n", err);
 }
 
 subsys_initcall(genl_init);
 
-EXPORT_SYMBOL(genl_sock);
 EXPORT_SYMBOL(genl_register_ops);
 EXPORT_SYMBOL(genl_unregister_ops);
 EXPORT_SYMBOL(genl_register_family);
 EXPORT_SYMBOL(genl_unregister_family);
+
+static int genlmsg_mcast(struct sk_buff *skb, u32 pid, unsigned long group,
+                         gfp_t flags)
+{
+        struct sk_buff *tmp;
+        struct net *net, *prev = NULL;
+        int err;
+
+        for_each_net_rcu(net) {
+                if (prev) {
+                        tmp = skb_clone(skb, flags);
+                        if (!tmp) {
+                                err = -ENOMEM;
+                                goto error;
+                        }
+                        err = nlmsg_multicast(prev->genl_sock, tmp,
+                                              pid, group, flags);
+                        if (err)
+                                goto error;
+                }
+
+                prev = net;
+        }
+
+        return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags);
+ error:
+        kfree_skb(skb);
+        return err;
+}
+
+int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group,
+                            gfp_t flags)
+{
+        return genlmsg_mcast(skb, pid, group, flags);
+}
+EXPORT_SYMBOL(genlmsg_multicast_allns);