netlink: fix NETLINK_RECV_NO_ENOBUFS in netlink_set_err()
Currently, ENOBUFS errors are reported to the socket via
netlink_set_err() even if NETLINK_RECV_NO_ENOBUFS is set. However,
that should not happen. This fixes this problem and it changes the
prototype of netlink_set_err() to return the number of sockets that
have set the NETLINK_RECV_NO_ENOBUFS socket option. This return
value is used in the next patch in these bugfix series.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 320d042..acbbae1 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1093,6 +1093,7 @@
struct netlink_set_err_data *p)
{
struct netlink_sock *nlk = nlk_sk(sk);
+ int ret = 0;
if (sk == p->exclude_sk)
goto out;
@@ -1104,10 +1105,15 @@
!test_bit(p->group - 1, nlk->groups))
goto out;
+ if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) {
+ ret = 1;
+ goto out;
+ }
+
sk->sk_err = p->code;
sk->sk_error_report(sk);
out:
- return 0;
+ return ret;
}
/**
@@ -1116,12 +1122,16 @@
* @pid: the PID of a process that we want to skip (if any)
* @groups: the broadcast group that will notice the error
* @code: error code, must be negative (as usual in kernelspace)
+ *
+ * This function returns the number of broadcast listeners that have set the
+ * NETLINK_RECV_NO_ENOBUFS socket option.
*/
-void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
+int netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
{
struct netlink_set_err_data info;
struct hlist_node *node;
struct sock *sk;
+ int ret = 0;
info.exclude_sk = ssk;
info.pid = pid;
@@ -1132,9 +1142,10 @@
read_lock(&nl_table_lock);
sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
- do_one_set_err(sk, &info);
+ ret += do_one_set_err(sk, &info);
read_unlock(&nl_table_lock);
+ return ret;
}
EXPORT_SYMBOL(netlink_set_err);