Commit 599e6f03 authored Mar 31, 2017 by Guillaume Nault Committed by Greg Kroah-Hartman Jul 05, 2017

l2tp: hold session while sending creation notifications



commit 5e6a9e5a3554a5b3db09cdc22253af1849c65dff upstream.

l2tp_session_find() doesn't take any reference on the returned session.
Therefore, the session may disappear while sending the notification.

Use l2tp_session_get() instead and decrement session's refcount once
the notification is sent.

Fixes: 33f72e6f ("l2tp : multicast notification to the registered listeners")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent d9face6f

net/l2tp/l2tp_netlink.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -634,10 +634,12 @@ static int l2tp_nl_cmd_session_create(struct sk_buff skb, struct genl_info inf
		session_id, peer_session_id, &cfg);

		if (ret >= 0) {
		session = l2tp_session_find(net, tunnel, session_id);
		if (session)
		session = l2tp_session_get(net, tunnel, session_id, false);
		if (session) {
		ret = l2tp_session_notify(&l2tp_nl_family, info, session,
		L2TP_CMD_SESSION_CREATE);
		l2tp_session_dec_refcount(session);
		}
		}

		out: