[PATCH net-next] netfilter: conntrack: dccp: try not to drop skb in conntrack

[Jason Xing <kerneljasonxing@gmail.com>]

From: Jason Xing <kernelxing@tencent.com>

It would be better not to drop skb in conntrack unless we have good
alternative as Florian said[1]. So we can treat the result of testing
skb's header pointer as nf_conntrack_tcp_packet() does.

[1]
Link: https://lore.kernel.org/all/20240307141025.GL4420@breakpoint.cc/

Signed-off-by: Jason Xing <kernelxing@tencent.com>
---
 net/netfilter/nf_conntrack_proto_dccp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c
index e2db1f4ec2df..ebc4f733bb2e 100644
--- a/net/netfilter/nf_conntrack_proto_dccp.c
+++ b/net/netfilter/nf_conntrack_proto_dccp.c
@@ -525,7 +525,7 @@ int nf_conntrack_dccp_packet(struct nf_conn *ct, struct sk_buff *skb,
 
 	dh = skb_header_pointer(skb, dataoff, sizeof(*dh), &_dh.dh);
 	if (!dh)
-		return NF_DROP;
+		return -NF_ACCEPT;
 
 	if (dccp_error(dh, skb, dataoff, state))
 		return -NF_ACCEPT;
@@ -533,7 +533,7 @@ int nf_conntrack_dccp_packet(struct nf_conn *ct, struct sk_buff *skb,
 	/* pull again, including possible 48 bit sequences and subtype header */
 	dh = dccp_header_pointer(skb, dataoff, dh, &_dh);
 	if (!dh)
-		return NF_DROP;
+		return -NF_ACCEPT;
 
 	type = dh->dccph_type;
 	if (!nf_ct_is_confirmed(ct) && !dccp_new(ct, skb, dh, state))
-- 
2.37.3