From 55193df8d6d33318435f19572bf5ea47a22eee28 Mon Sep 17 00:00:00 2001 From: Weiming Shi Date: Sun, 26 Apr 2026 09:53:51 -0700 Subject: [PATCH] bareudp: fix NULL pointer dereference in bareudp_fill_metadata_dst() [ Upstream commit aa6c6d9ee064aabfede4402fd1283424e649ca19 ] 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 Reviewed-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20260426165350.1663137-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/bareudp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c index 4acca20084d3..2b03967c140c 100644 --- a/drivers/net/bareudp.c +++ b/drivers/net/bareudp.c @@ -513,6 +513,9 @@ 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, &saddr, info, IPPROTO_UDP, use_cache);