14:51:00.024418 IP 192.168.122.1.41462 > netfilter.90: Flags [S], seq 4023580551, win 64240, options [mss 1460,sackOK,TS val 2149563785 ecr 0,nop,wscale 7], length 0 14:51:00.024454 IP netfilter.90 > 192.168.122.1.41462: Flags [S.], seq 727560212, ack 4023580552, win 0, options [mss 1460,sackOK,TS val 355031 ecr 2149563785,nop,wscale 7], length 0 14:51:00.024524 IP 192.168.122.1.41462 > netfilter.90: Flags [.], ack 1, win 502, options [nop,nop,TS val 2149563785 ecr 355031], length 0 14:51:00.024550 IP netfilter.90 > 192.168.122.1.41462: Flags [R.], seq 3567407084, ack 1, win 0, length 0 14:51:00.231196 IP 192.168.122.1.41462 > netfilter.90: Flags [.], ack 1, win 502, options [nop,nop,TS val 2149563992 ecr 355031], length 0 14:51:00.647911 IP 192.168.122.1.41462 > netfilter.90: Flags [.], ack 1, win 502, options [nop,nop,TS val 2149564408 ecr 355031], length 0 14:51:01.474395 IP 192.168.122.1.41462 > netfilter.90: Flags [.], ack 1, win 502, options [nop,nop,TS val 2149565235 ecr 355031], length 0 Fixes: 48b1de4c110a ("netfilter: add SYNPROXY core/target") Signed-off-by: Fernando Fernandez Mancera <ffmancera@xxxxxxxxxx> --- net/netfilter/nf_synproxy_core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nf_synproxy_core.c b/net/netfilter/nf_synproxy_core.c index 6676a3842a0c..cc6f951d156b 100644 --- a/net/netfilter/nf_synproxy_core.c +++ b/net/netfilter/nf_synproxy_core.c @@ -694,8 +694,11 @@ ipv4_synproxy_hook(void *priv, struct sk_buff *skb, } if (!th->syn || th->ack || - CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) + CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { + nf_ct_seqadj_init(ct, ctinfo, synproxy->isn - + ntohl(th->seq) + 1); break; + } /* Reopened connection - reset the sequence number and timestamp * adjustments, they will get initialized once the connection is @@ -1118,8 +1121,11 @@ ipv6_synproxy_hook(void *priv, struct sk_buff *skb, } if (!th->syn || th->ack || - CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) + CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { + nf_ct_seqadj_init(ct, ctinfo, synproxy->isn - + ntohl(th->seq) + 1); break; + } /* Reopened connection - reset the sequence number and timestamp * adjustments, they will get initialized once the connection is -- 2.20.1