From: Florian Westphal Date: Tue, 23 Apr 2024 13:44:28 +0000 (+0200) Subject: netfilter: conntrack: remove flowtable early-drop test X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=119c790a271de02dadb36ba0c1fc31a7d5d4c62b;p=linux.git netfilter: conntrack: remove flowtable early-drop test Not sure why this special case exists. Early drop logic (which kicks in when conntrack table is full) should be independent of flowtable offload and only consider assured bit (i.e., two-way traffic was seen). flowtable entries hold a reference to the conntrack entry (struct nf_conn) that has been offloaded. The conntrack use count is not decremented until after the entry is free'd. This change therefore will not result in exceeding the conntrack table limit. It does allow early-drop of tcp flows even when they've been offloaded, but only if they have been offloaded before syn-ack was received or after at least one peer has sent a fin. Currently 'fin' packet reception already stops offloading, so this should not impact offloading either. Cc: Vlad Buslov Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 6102dc09cdd3e..7ac20750c127b 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1440,8 +1440,6 @@ static bool gc_worker_can_early_drop(const struct nf_conn *ct) const struct nf_conntrack_l4proto *l4proto; u8 protonum = nf_ct_protonum(ct); - if (test_bit(IPS_OFFLOAD_BIT, &ct->status) && protonum != IPPROTO_UDP) - return false; if (!test_bit(IPS_ASSURED_BIT, &ct->status)) return true;