Commit 9bbb3d0d authored by Alexander Couzens's avatar Alexander Couzens Committed by Greg Kroah-Hartman

l2tp: protect tunnel->del_work by ref_count

[ Upstream commit 06a15f51cf3618e32a73871ee6a547ef7fd902b5 ]

There is a small chance that tunnel_free() is called before tunnel->del_work scheduled
resulting in a zero pointer dereference.
Signed-off-by: 's avatarAlexander Couzens <lynxis@fe80.eu>
Acked-by: 's avatarJames Chapman <jchapman@katalix.com>
Signed-off-by: 's avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: 's avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 61ce1520
......@@ -1381,7 +1381,7 @@ static void l2tp_tunnel_del_work(struct work_struct *work)
tunnel = container_of(work, struct l2tp_tunnel, del_work);
sk = l2tp_tunnel_sock_lookup(tunnel);
if (!sk)
return;
goto out;
sock = sk->sk_socket;
......@@ -1402,6 +1402,8 @@ static void l2tp_tunnel_del_work(struct work_struct *work)
}
l2tp_tunnel_sock_put(sk);
out:
l2tp_tunnel_dec_refcount(tunnel);
}
/* Create a socket for the tunnel, if one isn't set up by
......@@ -1731,8 +1733,13 @@ EXPORT_SYMBOL_GPL(l2tp_tunnel_create);
*/
int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel)
{
l2tp_tunnel_inc_refcount(tunnel);
l2tp_tunnel_closeall(tunnel);
return (false == queue_work(l2tp_wq, &tunnel->del_work));
if (false == queue_work(l2tp_wq, &tunnel->del_work)) {
l2tp_tunnel_dec_refcount(tunnel);
return 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(l2tp_tunnel_delete);
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment