From 48bd0d68cd4b849c0bb99dc1fb01b013ad4aa942 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Sat, 31 Aug 2019 01:40:33 -0300 Subject: netfilter: bridge: Drops IPv6 packets if IPv6 module is not loaded A kernel panic can happen if a host has disabled IPv6 on boot and have to process guest packets (coming from a bridge) using it's ip6tables. IPv6 packets need to be dropped if the IPv6 module is not loaded, and the host ip6tables will be used. Signed-off-by: Leonardo Bras Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/bridge/br_netfilter_hooks.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/bridge') diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c index d3f9592f4ff8..af7800103e51 100644 --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -496,6 +496,10 @@ static unsigned int br_nf_pre_routing(void *priv, if (!brnet->call_ip6tables && !br_opt_get(br, BROPT_NF_CALL_IP6TABLES)) return NF_ACCEPT; + if (!ipv6_mod_enabled()) { + pr_warn_once("Module ipv6 is disabled, so call_ip6tables is not supported."); + return NF_DROP; + } nf_bridge_pull_encap_header_rcsum(skb); return br_nf_pre_routing_ipv6(priv, skb, state); -- cgit v1.2.3-59-g8ed1b