From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Mon, 6 Jan 2020 12:56:47 +0100
Subject: netfilter: flowtable: refresh flow if hardware offload fails
Patch-mainline: v5.6-rc1
Git-commit: f698fe40829b21088d323c8b0a7c626571528fc6
References: bsc#1176447
If nf_flow_offload_add() fails to add the flow to hardware, then the
NF_FLOW_HW_REFRESH flag bit is set and the flow remains in the flowtable
software path.
If flowtable hardware offload is enabled, this patch enqueues a new
request to offload this flow to hardware.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/net/netfilter/nf_flow_table.h | 1 +
net/netfilter/nf_flow_table_core.c | 4 +++-
net/netfilter/nf_flow_table_ip.c | 13 +++++++++++++
net/netfilter/nf_flow_table_offload.c | 14 +++++---------
4 files changed, 22 insertions(+), 10 deletions(-)
--- a/include/net/netfilter/nf_flow_table.h
+++ b/include/net/netfilter/nf_flow_table.h
@@ -95,6 +95,7 @@ enum nf_flow_flags {
NF_FLOW_HW,
NF_FLOW_HW_DYING,
NF_FLOW_HW_DEAD,
+ NF_FLOW_HW_REFRESH,
};
enum flow_offload_type {
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -243,8 +243,10 @@ int flow_offload_add(struct nf_flowtable
return err;
}
- if (nf_flowtable_hw_offload(flow_table))
+ if (nf_flowtable_hw_offload(flow_table)) {
+ __set_bit(NF_FLOW_HW, &flow->flags);
nf_flow_offload_add(flow_table, flow);
+ }
return 0;
}
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -232,6 +232,13 @@ static unsigned int nf_flow_xmit_xfrm(st
return NF_STOLEN;
}
+static bool nf_flow_offload_refresh(struct nf_flowtable *flow_table,
+ struct flow_offload *flow)
+{
+ return nf_flowtable_hw_offload(flow_table) &&
+ test_and_clear_bit(NF_FLOW_HW_REFRESH, &flow->flags);
+}
+
unsigned int
nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
@@ -272,6 +279,9 @@ nf_flow_offload_ip_hook(void *priv, stru
if (nf_flow_state_check(flow, ip_hdr(skb)->protocol, skb, thoff))
return NF_ACCEPT;
+ if (unlikely(nf_flow_offload_refresh(flow_table, flow)))
+ nf_flow_offload_add(flow_table, flow);
+
if (nf_flow_offload_dst_check(&rt->dst)) {
flow_offload_teardown(flow);
return NF_ACCEPT;
@@ -498,6 +508,9 @@ nf_flow_offload_ipv6_hook(void *priv, st
sizeof(*ip6h)))
return NF_ACCEPT;
+ if (unlikely(nf_flow_offload_refresh(flow_table, flow)))
+ nf_flow_offload_add(flow_table, flow);
+
if (nf_flow_offload_dst_check(&rt->dst)) {
flow_offload_teardown(flow);
return NF_ACCEPT;
--- a/net/netfilter/nf_flow_table_offload.c
+++ b/net/netfilter/nf_flow_table_offload.c
@@ -654,20 +654,20 @@ static int flow_offload_rule_add(struct
return 0;
}
-static int flow_offload_work_add(struct flow_offload_work *offload)
+static void flow_offload_work_add(struct flow_offload_work *offload)
{
struct nf_flow_rule *flow_rule[FLOW_OFFLOAD_DIR_MAX];
int err;
err = nf_flow_offload_alloc(offload, flow_rule);
if (err < 0)
- return -ENOMEM;
+ return;
err = flow_offload_rule_add(offload, flow_rule);
+ if (err < 0)
+ set_bit(NF_FLOW_HW_REFRESH, &offload->flow->flags);
nf_flow_offload_destroy(flow_rule);
-
- return err;
}
static void flow_offload_work_del(struct flow_offload_work *offload)
@@ -712,7 +712,6 @@ static void flow_offload_work_handler(st
{
struct flow_offload_work *offload, *next;
LIST_HEAD(offload_pending_list);
- int ret;
spin_lock_bh(&flow_offload_pending_list_lock);
list_replace_init(&flow_offload_pending_list, &offload_pending_list);
@@ -721,9 +720,7 @@ static void flow_offload_work_handler(st
list_for_each_entry_safe(offload, next, &offload_pending_list, list) {
switch (offload->cmd) {
case FLOW_CLS_REPLACE:
- ret = flow_offload_work_add(offload);
- if (ret < 0)
- __clear_bit(NF_FLOW_HW, &offload->flow->flags);
+ flow_offload_work_add(offload);
break;
case FLOW_CLS_DESTROY:
flow_offload_work_del(offload);
@@ -776,7 +773,6 @@ void nf_flow_offload_add(struct nf_flowt
if (!offload)
return;
- __set_bit(NF_FLOW_HW, &flow->flags);
flow_offload_queue_work(offload);
}