bareudp_fill_metadata_dst() passes bareudp->sock to
udp_tunnel6_dst_lookup() in the IPv6 path without a NULL check.
The socket is only created in bareudp_open() and NULLed in
bareudp_stop(), so calling this function while the device is down
triggers a NULL dereference via sock->sk.
BUG: kernel NULL pointer dereference, address: 0000000000000018
RIP: 0010:udp_tunnel6_dst_lookup (net/ipv6/ip6_udp_tunnel.c:160)
Call Trace:
bareudp_fill_metadata_dst (drivers/net/bareudp.c:532)
do_execute_actions (net/openvswitch/actions.c:901)
ovs_execute_actions (net/openvswitch/actions.c:1589)
ovs_packet_cmd_execute (net/openvswitch/datapath.c:700)
genl_family_rcv_msg_doit (net/netlink/genetlink.c:1114)
genl_rcv_msg (net/netlink/genetlink.c:1209)
netlink_rcv_skb (net/netlink/af_netlink.c:2550)
Add a NULL check returning -ESHUTDOWN, consistent with the xmit paths
in the same driver.
Fixes: 571912c69f0e ("net: UDP tunnel encapsulation module for tunnelling different protocols like MPLS, IP, NSH etc.")
Reported-by: Xiang Mei
Signed-off-by: Weiming Shi
---
drivers/net/bareudp.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
index 0df3208783ad..da5866ba0699 100644
--- a/drivers/net/bareudp.c
+++ b/drivers/net/bareudp.c
@@ -529,6 +529,9 @@ static int bareudp_fill_metadata_dst(struct net_device *dev,
struct in6_addr saddr;
struct socket *sock = rcu_dereference(bareudp->sock);
+ if (!sock)
+ return -ESHUTDOWN;
+
dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock,
0, &saddr, &info->key,
sport, bareudp->port, info->key.tos,
--
2.43.0