From: Jason A. Donenfeld <Jason@xxxxxxxxx> commit 77fc73ac89be96ec8f39e8efa53885caa7cb3645 upstream. The previous commit fixed a memory leak on the send path in the event that IPv6 is disabled at compile time, but how did a packet even arrive there to begin with? It turns out we have previously allowed IPv6 endpoints even when IPv6 support is disabled at compile time. This is awkward and inconsistent. Instead, let's just ignore all things IPv6, the same way we do other malformed endpoints, in the case where IPv6 is disabled. Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireguard/socket.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/wireguard/socket.c +++ b/drivers/net/wireguard/socket.c @@ -242,7 +242,7 @@ int wg_socket_endpoint_from_skb(struct e endpoint->addr4.sin_addr.s_addr = ip_hdr(skb)->saddr; endpoint->src4.s_addr = ip_hdr(skb)->daddr; endpoint->src_if4 = skb->skb_iif; - } else if (skb->protocol == htons(ETH_P_IPV6)) { + } else if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) { endpoint->addr6.sin6_family = AF_INET6; endpoint->addr6.sin6_port = udp_hdr(skb)->source; endpoint->addr6.sin6_addr = ipv6_hdr(skb)->saddr; @@ -285,7 +285,7 @@ void wg_socket_set_peer_endpoint(struct peer->endpoint.addr4 = endpoint->addr4; peer->endpoint.src4 = endpoint->src4; peer->endpoint.src_if4 = endpoint->src_if4; - } else if (endpoint->addr.sa_family == AF_INET6) { + } else if (IS_ENABLED(CONFIG_IPV6) && endpoint->addr.sa_family == AF_INET6) { peer->endpoint.addr6 = endpoint->addr6; peer->endpoint.src6 = endpoint->src6; } else {