[PATCH AUTOSEL 4.19 32/83] netfilter: nf_tables: fix leaking object reference count

[PATCH AUTOSEL 4.19 32/83] netfilter: nf_tables: fix leaking object reference count

[Sasha Levin]

From: Taehee Yoo <ap420073@gmail.com>

[ Upstream commit b91d9036883793122cf6575ca4dfbfbdd201a83d ]

There is no code that decreases the reference count of stateful objects
in error path of the nft_add_set_elem(). this causes a leak of reference
count of stateful objects.

Test commands:
   $nft add table ip filter
   $nft add counter ip filter c1
   $nft add map ip filter m1 { type ipv4_addr : counter \;}
   $nft add element ip filter m1 { 1 : c1 }
   $nft add element ip filter m1 { 1 : c1 }
   $nft delete element ip filter m1 { 1 }
   $nft delete counter ip filter c1

Result:
   Error: Could not process rule: Device or resource busy
   delete counter ip filter c1
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

At the second 'nft add element ip filter m1 { 1 : c1 }', the reference
count of the 'c1' is increased then it tries to insert into the 'm1'. but
the 'm1' already has same element so it returns -EEXIST.
But it doesn't decrease the reference count of the 'c1' in the error path.
Due to a leak of the reference count of the 'c1', the 'c1' can't be
removed by 'nft delete counter ip filter c1'.

Fixes: 8aeff920dcc9 ("netfilter: nf_tables: add stateful object reference to set elements")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/nf_tables_api.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index ed9af46720e1..38654730230b 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4439,6 +4439,8 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
 err5:
 	kfree(trans);
 err4:
+	if (obj)
+		obj->use--;
 	kfree(elem.priv);
 err3:
 	if (nla[NFTA_SET_ELEM_DATA] != NULL)
-- 
2.19.1

[PATCH AUTOSEL 4.19 37/83] netfilter: nft_flow_offload: Fix reverse route lookup

[Sasha Levin]

From: wenxu <wenxu@ucloud.cn>

[ Upstream commit a799aea0988ea0d1b1f263e996fdad2f6133c680 ]

Using the following example:

	client 1.1.1.7 ---> 2.2.2.7 which dnat to 10.0.0.7 server

The first reply packet (ie. syn+ack) uses an incorrect destination
address for the reverse route lookup since it uses:

	daddr = ct->tuplehash[!dir].tuple.dst.u3.ip;

which is 2.2.2.7 in the scenario that is described above, while this
should be:

	daddr = ct->tuplehash[dir].tuple.src.u3.ip;

that is 10.0.0.7.

Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/nft_flow_offload.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
index 5fd4c57c79cc..e0c04851a349 100644
--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -29,10 +29,10 @@ static int nft_flow_route(const struct nft_pktinfo *pkt,
 	memset(&fl, 0, sizeof(fl));
 	switch (nft_pf(pkt)) {
 	case NFPROTO_IPV4:
-		fl.u.ip4.daddr = ct->tuplehash[!dir].tuple.dst.u3.ip;
+		fl.u.ip4.daddr = ct->tuplehash[dir].tuple.src.u3.ip;
 		break;
 	case NFPROTO_IPV6:
-		fl.u.ip6.daddr = ct->tuplehash[!dir].tuple.dst.u3.in6;
+		fl.u.ip6.daddr = ct->tuplehash[dir].tuple.src.u3.in6;
 		break;
 	}
 
-- 
2.19.1

[PATCH AUTOSEL 4.19 41/83] netfilter: nft_flow_offload: fix interaction with vrf slave device

[Sasha Levin]

From: wenxu <wenxu@ucloud.cn>

[ Upstream commit 10f4e765879e514e1ce7f52ed26603047af196e2 ]

In the forward chain, the iif is changed from slave device to master vrf
device. Thus, flow offload does not find a match on the lower slave
device.

This patch uses the cached route, ie. dst->dev, to update the iif and
oif fields in the flow entry.

After this patch, the following example works fine:

 # ip addr add dev eth0 1.1.1.1/24
 # ip addr add dev eth1 10.0.0.1/24
 # ip link add user1 type vrf table 1
 # ip l set user1 up
 # ip l set dev eth0 master user1
 # ip l set dev eth1 master user1

 # nft add table firewall
 # nft add flowtable f fb1 { hook ingress priority 0 \; devices = { eth0, eth1 } \; }
 # nft add chain f ftb-all {type filter hook forward priority 0 \; policy accept \; }
 # nft add rule f ftb-all ct zone 1 ip protocol tcp flow offload @fb1
 # nft add rule f ftb-all ct zone 1 ip protocol udp flow offload @fb1

Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/netfilter/nf_flow_table.h | 1 -
 net/netfilter/nf_flow_table_core.c    | 5 +++--
 net/netfilter/nft_flow_offload.c      | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h
index 0e355f4a3d76..0a3de10c6dec 100644
--- a/include/net/netfilter/nf_flow_table.h
+++ b/include/net/netfilter/nf_flow_table.h
@@ -84,7 +84,6 @@ struct flow_offload {
 struct nf_flow_route {
 	struct {
 		struct dst_entry	*dst;
-		int			ifindex;
 	} tuple[FLOW_OFFLOAD_DIR_MAX];
 };
 
diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
index d8125616edc7..e1537ace2b90 100644
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -28,6 +28,7 @@ flow_offload_fill_dir(struct flow_offload *flow, struct nf_conn *ct,
 {
 	struct flow_offload_tuple *ft = &flow->tuplehash[dir].tuple;
 	struct nf_conntrack_tuple *ctt = &ct->tuplehash[dir].tuple;
+	struct dst_entry *other_dst = route->tuple[!dir].dst;
 	struct dst_entry *dst = route->tuple[dir].dst;
 
 	ft->dir = dir;
@@ -50,8 +51,8 @@ flow_offload_fill_dir(struct flow_offload *flow, struct nf_conn *ct,
 	ft->src_port = ctt->src.u.tcp.port;
 	ft->dst_port = ctt->dst.u.tcp.port;
 
-	ft->iifidx = route->tuple[dir].ifindex;
-	ft->oifidx = route->tuple[!dir].ifindex;
+	ft->iifidx = other_dst->dev->ifindex;
+	ft->oifidx = dst->dev->ifindex;
 	ft->dst_cache = dst;
 }
 
diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
index e0c04851a349..4d7cf943fff2 100644
--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -30,9 +30,11 @@ static int nft_flow_route(const struct nft_pktinfo *pkt,
 	switch (nft_pf(pkt)) {
 	case NFPROTO_IPV4:
 		fl.u.ip4.daddr = ct->tuplehash[dir].tuple.src.u3.ip;
+		fl.u.ip4.flowi4_oif = nft_in(pkt)->ifindex;
 		break;
 	case NFPROTO_IPV6:
 		fl.u.ip6.daddr = ct->tuplehash[dir].tuple.src.u3.in6;
+		fl.u.ip6.flowi6_oif = nft_in(pkt)->ifindex;
 		break;
 	}
 
@@ -41,9 +43,7 @@ static int nft_flow_route(const struct nft_pktinfo *pkt,
 		return -ENOENT;
 
 	route->tuple[dir].dst		= this_dst;
-	route->tuple[dir].ifindex	= nft_in(pkt)->ifindex;
 	route->tuple[!dir].dst		= other_dst;
-	route->tuple[!dir].ifindex	= nft_out(pkt)->ifindex;
 
 	return 0;
 }
-- 
2.19.1

[PATCH AUTOSEL 4.19 56/83] netfilter: nft_flow_offload: fix checking method of conntrack helper

[Sasha Levin]

From: Henry Yen <henry.yen@mediatek.com>

[ Upstream commit 2314e879747e82896f51cce4488f6a00f3e1af7b ]

This patch uses nfct_help() to detect whether an established connection
needs conntrack helper instead of using test_bit(IPS_HELPER_BIT,
&ct->status).

The reason is that IPS_HELPER_BIT is only set when using explicit CT
target.

However, in the case that a device enables conntrack helper via command
"echo 1 > /proc/sys/net/netfilter/nf_conntrack_helper", the status of
IPS_HELPER_BIT will not present any change, and consequently it loses
the checking ability in the context.

Signed-off-by: Henry Yen <henry.yen@mediatek.com>
Reviewed-by: Ryder Lee <ryder.lee@mediatek.com>
Tested-by: John Crispin <john@phrozen.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/nft_flow_offload.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
index 4d7cf943fff2..436cc14cfc59 100644
--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -12,6 +12,7 @@
 #include <net/netfilter/nf_conntrack_core.h>
 #include <linux/netfilter/nf_conntrack_common.h>
 #include <net/netfilter/nf_flow_table.h>
+#include <net/netfilter/nf_conntrack_helper.h>
 
 struct nft_flow_offload {
 	struct nft_flowtable	*flowtable;
@@ -66,6 +67,7 @@ static void nft_flow_offload_eval(const struct nft_expr *expr,
 {
 	struct nft_flow_offload *priv = nft_expr_priv(expr);
 	struct nf_flowtable *flowtable = &priv->flowtable->data;
+	const struct nf_conn_help *help;
 	enum ip_conntrack_info ctinfo;
 	struct nf_flow_route route;
 	struct flow_offload *flow;
@@ -88,7 +90,8 @@ static void nft_flow_offload_eval(const struct nft_expr *expr,
 		goto out;
 	}
 
-	if (test_bit(IPS_HELPER_BIT, &ct->status))
+	help = nfct_help(ct);
+	if (help)
 		goto out;
 
 	if (ctinfo == IP_CT_NEW ||
-- 
2.19.1