From: Florian Westphal <fw@xxxxxxxxx> --ctdir ORIGINAL matches REPLY packets, and vv: userspace sets "invert_flags &= ~XT_CONNTRACK_DIRECTION" in ORIGINAL case. Thus: (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) ^ !!(info->invert_flags & XT_CONNTRACK_DIRECTION)) yields "1 ^ 0", which is true -> returns false. Reproducer: iptables -I OUTPUT 1 -p tcp --syn -m conntrack --ctdir ORIGINAL Signed-off-by: Florian Westphal <fwestphal@xxxxxxxxxx> Signed-off-by: Patrick McHardy <kaber@xxxxxxxxx> --- net/netfilter/xt_conntrack.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/netfilter/xt_conntrack.c b/net/netfilter/xt_conntrack.c index 2c0086a..481a86f 100644 --- a/net/netfilter/xt_conntrack.c +++ b/net/netfilter/xt_conntrack.c @@ -195,7 +195,7 @@ conntrack_mt(const struct sk_buff *skb, struct xt_action_param *par, return info->match_flags & XT_CONNTRACK_STATE; if ((info->match_flags & XT_CONNTRACK_DIRECTION) && (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) ^ - !!(info->invert_flags & XT_CONNTRACK_DIRECTION)) + !(info->invert_flags & XT_CONNTRACK_DIRECTION)) return false; if (info->match_flags & XT_CONNTRACK_ORIGSRC) -- 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html