From: Jason Xing <kernelxing@xxxxxxxxxxx> At the beginning in 2009 one patch [1] introduced collecting drop counter in nf_conntrack_in() by returning -NF_DROP. Later, another patch [2] changed the return value of tcp_packet() which now is renamed to nf_conntrack_tcp_packet() from -NF_DROP to NF_DROP. As we can see, that -NF_DROP should be corrected. Similarly, there are other two points where the -NF_DROP is used. Well, as NF_DROP is equal to 0, inverting NF_DROP makes no sense as patch [2] said many years ago. [1] commit 7d1e04598e5e ("netfilter: nf_conntrack: account packets drop by tcp_packet()") [2] commit ec8d540969da ("netfilter: conntrack: fix dropping packet after l4proto->packet()") Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx> --- v2 Link: https://lore.kernel.org/all/20240325031945.15760-1-kerneljasonxing@xxxxxxxxx/ 1. squash three patches into one --- net/ipv4/netfilter/iptable_filter.c | 2 +- net/ipv6/netfilter/ip6table_filter.c | 2 +- net/netfilter/nf_conntrack_core.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c index b9062f4552ac..3ab908b74795 100644 --- a/net/ipv4/netfilter/iptable_filter.c +++ b/net/ipv4/netfilter/iptable_filter.c @@ -44,7 +44,7 @@ static int iptable_filter_table_init(struct net *net) return -ENOMEM; /* Entry 1 is the FORWARD hook */ ((struct ipt_standard *)repl->entries)[1].target.verdict = - forward ? -NF_ACCEPT - 1 : -NF_DROP - 1; + forward ? -NF_ACCEPT - 1 : NF_DROP - 1; err = ipt_register_table(net, &packet_filter, repl, filter_ops); kfree(repl); diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c index df785ebda0ca..e8992693e14a 100644 --- a/net/ipv6/netfilter/ip6table_filter.c +++ b/net/ipv6/netfilter/ip6table_filter.c @@ -43,7 +43,7 @@ static int ip6table_filter_table_init(struct net *net) return -ENOMEM; /* Entry 1 is the FORWARD hook */ ((struct ip6t_standard *)repl->entries)[1].target.verdict = - forward ? -NF_ACCEPT - 1 : -NF_DROP - 1; + forward ? -NF_ACCEPT - 1 : NF_DROP - 1; err = ip6t_register_table(net, &packet_filter, repl, filter_ops); kfree(repl); diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index c63868666bd9..6102dc09cdd3 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -2024,7 +2024,7 @@ nf_conntrack_in(struct sk_buff *skb, const struct nf_hook_state *state) goto repeat; NF_CT_STAT_INC_ATOMIC(state->net, invalid); - if (ret == -NF_DROP) + if (ret == NF_DROP) NF_CT_STAT_INC_ATOMIC(state->net, drop); ret = -ret; -- 2.37.3