diff mbox series

[4.4,50/65] l2tp: hold tunnel while processing genl delete command

Message ID 20200526183923.358855333@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman May 26, 2020, 6:53 p.m. UTC 
From: Guillaume Nault <g.nault@alphalink.fr>

commit bb0a32ce4389e17e47e198d2cddaf141561581ad upstream.

l2tp_nl_cmd_tunnel_delete() needs to take a reference on the tunnel, to
prevent it from being concurrently freed by l2tp_tunnel_destruct().

Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/l2tp/l2tp_netlink.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/net/l2tp/l2tp_netlink.c
+++ b/net/l2tp/l2tp_netlink.c
@@ -280,8 +280,8 @@  static int l2tp_nl_cmd_tunnel_delete(str
 	}
 	tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
 
-	tunnel = l2tp_tunnel_find(net, tunnel_id);
-	if (tunnel == NULL) {
+	tunnel = l2tp_tunnel_get(net, tunnel_id);
+	if (!tunnel) {
 		ret = -ENODEV;
 		goto out;
 	}
@@ -291,6 +291,8 @@  static int l2tp_nl_cmd_tunnel_delete(str
 
 	l2tp_tunnel_delete(tunnel);
 
+	l2tp_tunnel_dec_refcount(tunnel);
+
 out:
 	return ret;
 }