2 files changed, 50 insertions, 60 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index cd96ed3ccee4..6ef64adf7362 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -83,9 +83,9 @@ struct netlink_sock {
         struct module           *module;
 };
 
-struct listeners_rcu_head {
-        struct rcu_head rcu_head;
-        void *ptr;
+struct listeners {
+        struct rcu_head         rcu;
+        unsigned long           masks[0];
 };
 
 #define NETLINK_KERNEL_SOCKET   0x1
@@ -119,7 +119,7 @@ struct nl_pid_hash {
 struct netlink_table {
         struct nl_pid_hash hash;
         struct hlist_head mc_list;
-        unsigned long *listeners;
+        struct listeners __rcu *listeners;
         unsigned int nl_nonroot;
         unsigned int groups;
         struct mutex *cb_mutex;
@@ -338,7 +338,7 @@ netlink_update_listeners(struct sock *sk)
                         if (i < NLGRPLONGS(nlk_sk(sk)->ngroups))
                                 mask |= nlk_sk(sk)->groups[i];
                 }
-                tbl->listeners[i] = mask;
+                tbl->listeners->masks[i] = mask;
         }
         /* this function is only called with the netlink table "grabbed", which
          * makes sure updates are visible before bind or setsockopt return. */
@@ -936,7 +936,7 @@ EXPORT_SYMBOL(netlink_unicast);
 int netlink_has_listeners(struct sock *sk, unsigned int group)
 {
         int res = 0;
-        unsigned long *listeners;
+        struct listeners *listeners;
 
         BUG_ON(!netlink_is_kernel(sk));
 
@@ -944,7 +944,7 @@ int netlink_has_listeners(struct sock *sk, unsigned int group)
         listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners);
 
         if (group - 1 < nl_table[sk->sk_protocol].groups)
-                res = test_bit(group - 1, listeners);
+                res = test_bit(group - 1, listeners->masks);
 
         rcu_read_unlock();
 
@@ -1362,17 +1362,8 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
 
         NETLINK_CB(skb).pid     = nlk->pid;
         NETLINK_CB(skb).dst_group = dst_group;
-        NETLINK_CB(skb).loginuid = audit_get_loginuid(current);
-        NETLINK_CB(skb).sessionid = audit_get_sessionid(current);
-        security_task_getsecid(current, &(NETLINK_CB(skb).sid));
         memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
 
-        /* What can I do? Netlink is asynchronous, so that
-           we will have to save current capabilities to
-           check them, when this message will be delivered
-           to corresponding kernel module.   --ANK (980802)
-         */
-
         err = -EFAULT;
         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
                 kfree_skb(skb);
@@ -1407,7 +1398,7 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
         int noblock = flags&MSG_DONTWAIT;
         size_t copied;
         struct sk_buff *skb, *data_skb;
-        int err;
+        int err, ret;
 
         if (flags&MSG_OOB)
                 return -EOPNOTSUPP;
@@ -1470,8 +1461,13 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
 
         skb_free_datagram(sk, skb);
 
-        if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2)
-                netlink_dump(sk);
+        if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
+                ret = netlink_dump(sk);
+                if (ret) {
+                        sk->sk_err = ret;
+                        sk->sk_error_report(sk);
+                }
+        }
 
         scm_recv(sock, msg, siocb->scm, flags);
 out:
@@ -1498,7 +1494,7 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
         struct socket *sock;
         struct sock *sk;
         struct netlink_sock *nlk;
-        unsigned long *listeners = NULL;
+        struct listeners *listeners = NULL;
 
         BUG_ON(!nl_table);
 
@@ -1523,8 +1519,7 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
         if (groups < 32)
                 groups = 32;
 
-        listeners = kzalloc(NLGRPSZ(groups) + sizeof(struct listeners_rcu_head),
-                            GFP_KERNEL);
+        listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
         if (!listeners)
                 goto out_sock_release;
 
@@ -1541,7 +1536,7 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
         netlink_table_grab();
         if (!nl_table[unit].registered) {
                 nl_table[unit].groups = groups;
-                nl_table[unit].listeners = listeners;
+                rcu_assign_pointer(nl_table[unit].listeners, listeners);
                 nl_table[unit].cb_mutex = cb_mutex;
                 nl_table[unit].module = module;
                 nl_table[unit].registered = 1;
@@ -1571,44 +1566,23 @@ netlink_kernel_release(struct sock *sk)
 }
 EXPORT_SYMBOL(netlink_kernel_release);
 
-
-static void netlink_free_old_listeners(struct rcu_head *rcu_head)
-{
-        struct listeners_rcu_head *lrh;
-
-        lrh = container_of(rcu_head, struct listeners_rcu_head, rcu_head);
-        kfree(lrh->ptr);
-}
-
 int __netlink_change_ngroups(struct sock *sk, unsigned int groups)
 {
-        unsigned long *listeners, *old = NULL;
-        struct listeners_rcu_head *old_rcu_head;
+        struct listeners *new, *old;
         struct netlink_table *tbl = &nl_table[sk->sk_protocol];
 
         if (groups < 32)
                 groups = 32;
 
         if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) {
-                listeners = kzalloc(NLGRPSZ(groups) +
-                                    sizeof(struct listeners_rcu_head),
-                                    GFP_ATOMIC);
-                if (!listeners)
+                new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC);
+                if (!new)
                         return -ENOMEM;
-                old = tbl->listeners;
-                memcpy(listeners, old, NLGRPSZ(tbl->groups));
-                rcu_assign_pointer(tbl->listeners, listeners);
-                /*
-                 * Free the old memory after an RCU grace period so we
-                 * don't leak it. We use call_rcu() here in order to be
-                 * able to call this function from atomic contexts. The
-                 * allocation of this memory will have reserved enough
-                 * space for struct listeners_rcu_head at the end.
-                 */
-                old_rcu_head = (void *)(tbl->listeners +
-                                        NLGRPLONGS(tbl->groups));
-                old_rcu_head->ptr = old;
-                call_rcu(&old_rcu_head->rcu_head, netlink_free_old_listeners);
+                old = rcu_dereference_raw(tbl->listeners);
+                memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups));
+                rcu_assign_pointer(tbl->listeners, new);
+
+                kfree_rcu(old, rcu);
         }
         tbl->groups = groups;
 
@@ -1752,6 +1726,7 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
         struct netlink_callback *cb;
         struct sock *sk;
         struct netlink_sock *nlk;
+        int ret;
 
         cb = kzalloc(sizeof(*cb), GFP_KERNEL);
         if (cb == NULL)
@@ -1780,9 +1755,13 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
         nlk->cb = cb;
         mutex_unlock(nlk->cb_mutex);
 
-        netlink_dump(sk);
+        ret = netlink_dump(sk);
+
         sock_put(sk);
 
+        if (ret)
+                return ret;
+
         /* We successfully started a dump, by returning -EINTR we
          * signal not to send ACK even if it was requested.
          */
@@ -2006,7 +1985,7 @@ static int netlink_seq_show(struct seq_file *seq, void *v)
                 struct sock *s = v;
                 struct netlink_sock *nlk = nlk_sk(s);
 
-                seq_printf(seq, "%p %-3d %-6d %08x %-8d %-8d %p %-8d %-8d %-8lu\n",
+                seq_printf(seq, "%pK %-3d %-6d %08x %-8d %-8d %pK %-8d %-8d %-8lu\n",
                            s,
                            s->sk_protocol,
                            nlk->pid,
@@ -2104,18 +2083,17 @@ static void __net_exit netlink_net_exit(struct net *net)
 
 static void __init netlink_add_usersock_entry(void)
 {
-        unsigned long *listeners;
+        struct listeners *listeners;
         int groups = 32;
 
-        listeners = kzalloc(NLGRPSZ(groups) + sizeof(struct listeners_rcu_head),
-                            GFP_KERNEL);
+        listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
         if (!listeners)
-                panic("netlink_add_usersock_entry: Cannot allocate listneres\n");
+                panic("netlink_add_usersock_entry: Cannot allocate listeners\n");
 
         netlink_table_grab();
 
         nl_table[NETLINK_USERSOCK].groups = groups;
-        nl_table[NETLINK_USERSOCK].listeners = listeners;
+        rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners);
         nl_table[NETLINK_USERSOCK].module = THIS_MODULE;
         nl_table[NETLINK_USERSOCK].registered = 1;
 
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 26ed3e8587c2..1781d99145e2 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -547,8 +547,20 @@ static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
         info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;
         info.attrs = family->attrbuf;
         genl_info_net_set(&info, net);
+        memset(&info.user_ptr, 0, sizeof(info.user_ptr));
 
-        return ops->doit(skb, &info);
+        if (family->pre_doit) {
+                err = family->pre_doit(ops, skb, &info);
+                if (err)
+                        return err;
+        }
+
+        err = ops->doit(skb, &info);
+
+        if (family->post_doit)
+                family->post_doit(ops, skb, &info);
+
+        return err;
 }
 
 static void genl_rcv(struct sk_buff *skb)