netlink: only do not deliver to tap when both sides are kernel sks (73bfd370) · Commits · 戴 / test

We should also deliver packets to nlmon devices when we are in netlink_unicast_kernel(), and only one of the {src,dst} sockets is user sk and the other one kernel sk. That's e.g. the case in netlink diag, netlink route, etc. Still, forbid to deliver messages from kernel to kernel sks. Signed-off-by:

Daniel Borkmann <dborkman@redhat.com> Signed-off-by:

Jakub Zawadzki <darkjames-ws@darkjames.pl> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/netlink/af_netlink.c

+8 −5

Original line number	Diff line number	Diff line
		@@ -239,6 +239,13 @@ static void netlink_deliver_tap(struct sk_buff *skb)
		rcu_read_unlock();
		}

		static void netlink_deliver_tap_kernel(struct sock dst, struct sock src,
		struct sk_buff *skb)
		{
		if (!(netlink_is_kernel(dst) && netlink_is_kernel(src)))
		netlink_deliver_tap(skb);
		}

		static void netlink_overrun(struct sock *sk)
		{
		struct netlink_sock *nlk = nlk_sk(sk);
		@@ -1697,14 +1704,10 @@ static int netlink_unicast_kernel(struct sock sk, struct sk_buff skb,

		ret = -ECONNREFUSED;
		if (nlk->netlink_rcv != NULL) {
		/* We could do a netlink_deliver_tap(skb) here as well
		* but since this is intended for the kernel only, we
		* should rather let it stay under the hood.
		*/

		ret = skb->len;
		netlink_skb_set_owner_r(skb, sk);
		NETLINK_CB(skb).sk = ssk;
		netlink_deliver_tap_kernel(sk, ssk, skb);
		nlk->netlink_rcv(skb);
		consume_skb(skb);
		} else {

Admin message