netfilter: nf_flow_table: ignore DF bit setting

Its irrelevant if the DF bit is set or not, we must pass packet to
stack in either case.

If the DF bit is set, we must pass it to stack so the appropriate
ICMP error can be generated.

If the DF is not set, we must pass it to stack for fragmentation.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2019-05-21 13:24:30 +02:00 committed by Pablo Neira Ayuso
parent 6bac76db1d
commit e75b3e1c9b

View File

@ -243,8 +243,7 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
rt = (struct rtable *)flow->tuplehash[dir].tuple.dst_cache;
outdev = rt->dst.dev;
if (unlikely(nf_flow_exceeds_mtu(skb, flow->tuplehash[dir].tuple.mtu)) &&
(ip_hdr(skb)->frag_off & htons(IP_DF)) != 0)
if (unlikely(nf_flow_exceeds_mtu(skb, flow->tuplehash[dir].tuple.mtu)))
return NF_ACCEPT;
if (skb_try_make_writable(skb, sizeof(*iph)))