struct module *module;
};
+struct listeners_rcu_head {
+ struct rcu_head rcu_head;
+ void *ptr;
+};
+
#define NETLINK_KERNEL_SOCKET 0x1
#define NETLINK_RECV_PKTINFO 0x2
#define NETLINK_BROADCAST_SEND_ERROR 0x4
* this, _but_ remember, it adds useless work on UP machines.
*/
-static void netlink_table_grab(void)
+void netlink_table_grab(void)
__acquires(nl_table_lock)
{
+ might_sleep();
+
write_lock_irq(&nl_table_lock);
if (atomic_read(&nl_table_users)) {
}
}
-static void netlink_table_ungrab(void)
+void netlink_table_ungrab(void)
__releases(nl_table_lock)
{
write_unlock_irq(&nl_table_lock);
return 0;
}
-static int netlink_create(struct net *net, struct socket *sock, int protocol)
+static int netlink_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
{
struct module *module = NULL;
struct mutex *cb_mutex;
skb_queue_purge(&sk->sk_write_queue);
- if (nlk->pid && !nlk->subscriptions) {
+ if (nlk->pid) {
struct netlink_notify n = {
.net = sock_net(sk),
.protocol = sk->sk_protocol,
{
struct sock *sk = sock->sk;
struct netlink_sock *nlk = nlk_sk(sk);
- struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
+ DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr);
nladdr->nl_family = AF_NETLINK;
nladdr->nl_pad = 0;
if (sk == p->exclude_sk)
goto out;
- if (sock_net(sk) != sock_net(p->exclude_sk))
+ if (!net_eq(sock_net(sk), sock_net(p->exclude_sk)))
goto out;
if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
}
static int netlink_setsockopt(struct socket *sock, int level, int optname,
- char __user *optval, int optlen)
+ char __user *optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
struct netlink_sock *nlk = nlk_sk(sk);
struct netlink_sock *nlk = nlk_sk(sk);
int noblock = flags&MSG_DONTWAIT;
size_t copied;
- struct sk_buff *skb;
+ struct sk_buff *skb, *frag __maybe_unused = NULL;
int err;
if (flags&MSG_OOB)
if (skb == NULL)
goto out;
+#ifdef CONFIG_COMPAT_NETLINK_MESSAGES
+ if (unlikely(skb_shinfo(skb)->frag_list)) {
+ bool need_compat = !!(flags & MSG_CMSG_COMPAT);
+
+ /*
+ * If this skb has a frag_list, then here that means that
+ * we will have to use the frag_list skb for compat tasks
+ * and the regular skb for non-compat tasks.
+ *
+ * The skb might (and likely will) be cloned, so we can't
+ * just reset frag_list and go on with things -- we need to
+ * keep that. For the compat case that's easy -- simply get
+ * a reference to the compat skb and free the regular one
+ * including the frag. For the non-compat case, we need to
+ * avoid sending the frag to the user -- so assign NULL but
+ * restore it below before freeing the skb.
+ */
+ if (need_compat) {
+ struct sk_buff *compskb = skb_shinfo(skb)->frag_list;
+ skb_get(compskb);
+ kfree_skb(skb);
+ skb = compskb;
+ } else {
+ frag = skb_shinfo(skb)->frag_list;
+ skb_shinfo(skb)->frag_list = NULL;
+ }
+ }
+#endif
+
msg->msg_namelen = 0;
copied = skb->len;
siocb->scm->creds = *NETLINK_CREDS(skb);
if (flags & MSG_TRUNC)
copied = skb->len;
+
+#ifdef CONFIG_COMPAT_NETLINK_MESSAGES
+ skb_shinfo(skb)->frag_list = frag;
+#endif
+
skb_free_datagram(sk, skb);
if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2)
if (groups < 32)
groups = 32;
- listeners = kzalloc(NLGRPSZ(groups), GFP_KERNEL);
+ listeners = kzalloc(NLGRPSZ(groups) + sizeof(struct listeners_rcu_head),
+ GFP_KERNEL);
if (!listeners)
goto out_sock_release;
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 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)
+ 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);
+ }
+ tbl->groups = groups;
+
+ return 0;
+}
+
/**
* netlink_change_ngroups - change number of multicast groups
*
*/
int netlink_change_ngroups(struct sock *sk, unsigned int groups)
{
- unsigned long *listeners, *old = NULL;
- struct netlink_table *tbl = &nl_table[sk->sk_protocol];
- int err = 0;
-
- if (groups < 32)
- groups = 32;
+ int err;
netlink_table_grab();
- if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) {
- listeners = kzalloc(NLGRPSZ(groups), GFP_ATOMIC);
- if (!listeners) {
- err = -ENOMEM;
- goto out_ungrab;
- }
- old = tbl->listeners;
- memcpy(listeners, old, NLGRPSZ(tbl->groups));
- rcu_assign_pointer(tbl->listeners, listeners);
- }
- tbl->groups = groups;
-
- out_ungrab:
+ err = __netlink_change_ngroups(sk, groups);
netlink_table_ungrab();
- synchronize_rcu();
- kfree(old);
+
return err;
}
-EXPORT_SYMBOL(netlink_change_ngroups);
+
+void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
+{
+ struct sock *sk;
+ struct hlist_node *node;
+ struct netlink_table *tbl = &nl_table[ksk->sk_protocol];
+
+ sk_for_each_bound(sk, node, &tbl->mc_list)
+ netlink_update_socket_mc(nlk_sk(sk), group, 0);
+}
/**
* netlink_clear_multicast_users - kick off multicast listeners
*/
void netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
{
- struct sock *sk;
- struct hlist_node *node;
- struct netlink_table *tbl = &nl_table[ksk->sk_protocol];
-
netlink_table_grab();
-
- sk_for_each_bound(sk, node, &tbl->mc_list)
- netlink_update_socket_mc(nlk_sk(sk), group, 0);
-
+ __netlink_clear_multicast_users(ksk, group);
netlink_table_ungrab();
}
-EXPORT_SYMBOL(netlink_clear_multicast_users);
void netlink_set_nonroot(int protocol, unsigned int flags)
{
}
int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
- struct nlmsghdr *nlh,
+ const struct nlmsghdr *nlh,
int (*dump)(struct sk_buff *skb,
struct netlink_callback *),
int (*done)(struct netlink_callback *))
}
rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
- NLMSG_ERROR, sizeof(struct nlmsgerr), 0);
+ NLMSG_ERROR, payload, 0);
errmsg = nlmsg_data(rep);
errmsg->error = err;
memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh));
.sendpage = sock_no_sendpage,
};
-static struct net_proto_family netlink_family_ops = {
+static const struct net_proto_family netlink_family_ops = {
.family = PF_NETLINK,
.create = netlink_create,
.owner = THIS_MODULE, /* for consistency 8) */
if (!nl_table)
goto panic;
- if (num_physpages >= (128 * 1024))
- limit = num_physpages >> (21 - PAGE_SHIFT);
+ if (totalram_pages >= (128 * 1024))
+ limit = totalram_pages >> (21 - PAGE_SHIFT);
else
- limit = num_physpages >> (23 - PAGE_SHIFT);
+ limit = totalram_pages >> (23 - PAGE_SHIFT);
order = get_bitmask_order(limit) - 1 + PAGE_SHIFT;
limit = (1UL << order) / sizeof(struct hlist_head);