From 2bb4ecb3349c19a04e2219113b169646ca194608 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 24 Oct 2023 21:09:47 +0200 Subject: [PATCH] netfilter: flowtable: GC pushes back packets to classic path [ Upstream commit 735795f68b37e9bb49f642407a0d49b1631ea1c7 ] Since 41f2c7c342d3 ("net/sched: act_ct: Fix promotion of offloaded unreplied tuple"), flowtable GC pushes back flows with IPS_SEEN_REPLY back to classic path in every run, ie. every second. This is because of a new check for NF_FLOW_HW_ESTABLISHED which is specific of sched/act_ct. In Netfilter's flowtable case, NF_FLOW_HW_ESTABLISHED never gets set on and IPS_SEEN_REPLY is unreliable since users decide when to offload the flow before, such bit might be set on at a later stage. Fix it by adding a custom .gc handler that sched/act_ct can use to deal with its NF_FLOW_HW_ESTABLISHED bit. Fixes: 41f2c7c342d3 ("net/sched: act_ct: Fix promotion of offloaded unreplied tuple") Reported-by: Vladimir Smelhaus Reviewed-by: Paul Blakey Signed-off-by: Pablo Neira Ayuso Stable-dep-of: 125f1c7f26ff ("net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table") Signed-off-by: Sasha Levin --- include/net/netfilter/nf_flow_table.h | 1 + net/netfilter/nf_flow_table_core.c | 14 +++++++------- net/sched/act_ct.c | 7 +++++++ 3 files changed, 15 insertions(+), 7 deletions(-) diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h index f37f9f34430c..0b163ead95c9 100644 --- a/include/net/netfilter/nf_flow_table.h +++ b/include/net/netfilter/nf_flow_table.h @@ -53,6 +53,7 @@ struct nf_flowtable_type { struct list_head list; int family; int (*init)(struct nf_flowtable *ft); + bool (*gc)(const struct flow_offload *flow); int (*setup)(struct nf_flowtable *ft, struct net_device *dev, enum flow_block_command cmd); diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c index baddb93a5e8c..c1d99cb370b4 100644 --- a/net/netfilter/nf_flow_table_core.c +++ b/net/netfilter/nf_flow_table_core.c @@ -331,12 +331,6 @@ void flow_offload_refresh(struct nf_flowtable *flow_table, } EXPORT_SYMBOL_GPL(flow_offload_refresh); -static bool nf_flow_is_outdated(const struct flow_offload *flow) -{ - return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) && - !test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags); -} - static inline bool nf_flow_has_expired(const struct flow_offload *flow) { return nf_flow_timeout_delta(flow->timeout) <= 0; @@ -422,12 +416,18 @@ nf_flow_table_iterate(struct nf_flowtable *flow_table, return err; } +static bool nf_flow_custom_gc(struct nf_flowtable *flow_table, + const struct flow_offload *flow) +{ + return flow_table->type->gc && flow_table->type->gc(flow); +} + static void nf_flow_offload_gc_step(struct nf_flowtable *flow_table, struct flow_offload *flow, void *data) { if (nf_flow_has_expired(flow) || nf_ct_is_dying(flow->ct) || - nf_flow_is_outdated(flow)) + nf_flow_custom_gc(flow_table, flow)) flow_offload_teardown(flow); if (test_bit(NF_FLOW_TEARDOWN, &flow->flags)) { diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c index b80a58d3bf0f..4d34474f2cc0 100644 --- a/net/sched/act_ct.c +++ b/net/sched/act_ct.c @@ -274,7 +274,14 @@ static int tcf_ct_flow_table_fill_actions(struct net *net, return err; } +static bool tcf_ct_flow_is_outdated(const struct flow_offload *flow) +{ + return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) && + !test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags); +} + static struct nf_flowtable_type flowtable_ct = { + .gc = tcf_ct_flow_is_outdated, .action = tcf_ct_flow_table_fill_actions, .owner = THIS_MODULE, };