On Wed, Jan 23, 2019 at 10:19:41AM +0800, Mao Wenan wrote:
From: Florian Westphal fw@strlen.de
[ Upstream commit 0ed4229b08c13c84a3c301a08defdc9e7f4467e6 ]
don't bother with pathological cases, they only waste cycles. IPv6 requires a minimum MTU of 1280 so we should never see fragments smaller than this (except last frag).
v3: don't use awkward "-offset + len" v2: drop IPv4 part, which added same check w. IPV4_MIN_MTU (68). There were concerns that there could be even smaller frags generated by intermediate nodes, e.g. on radio networks.
Cc: Peter Oskolkov posk@google.com Cc: Eric Dumazet edumazet@google.com Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Mao Wenan maowenan@huawei.com
net/ipv6/netfilter/nf_conntrack_reasm.c | 4 ++++ net/ipv6/reassembly.c | 4 ++++ 2 files changed, 8 insertions(+)
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 9cd8863..c5033a2 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -602,6 +602,10 @@ struct sk_buff *nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 use hdr = ipv6_hdr(clone); fhdr = (struct frag_hdr *)skb_transport_header(clone);
- if (skb->len - skb_network_offset(skb) < IPV6_MIN_MTU &&
fhdr->frag_off & htons(IP6_MF))return -EINVAL;
This backport is incorrect, you should be returning a pointer, right?
How did you test this? This should have blown up under test :(
I'm going to drop this whole series. Please fix it up and test it properly and then resend.
thanks,
greg k-h