[PATCH net] bonding: don't set oif to bond dev when getting NS target destination

[Hangbin Liu <liuhangbin@gmail.com>]

Unlike IPv4, IPv6 routing strictly requires the source address to be valid
on the outgoing interface. If the NS target is set to a remote VLAN interface,
and the source address is also configured on a VLAN over a bond interface,
setting the oif to the bond device will fail to retrieve the correct
destination route.

Fix this by not setting the oif to the bond device when retrieving the NS
target destination. This allows the correct destination device (the VLAN
interface) to be determined, so that bond_verify_device_path can return the
proper VLAN tags for sending NS messages.

Reported-by: David Wilder <wilder@us.ibm.com>
Closes: https://lore.kernel.org/netdev/aGOKggdfjv0cApTO@fedora/
Suggested-by: Jay Vosburgh <jv@jvosburgh.net>
Fixes: 4e24be018eb9 ("bonding: add new parameter ns_targets")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
---
 drivers/net/bonding/bond_main.c               |  1 -
 .../drivers/net/bonding/bond_options.sh       | 59 +++++++++++++++++++
 2 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 257333c88710..30cf97f4e814 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -3355,7 +3355,6 @@ static void bond_ns_send_all(struct bonding *bond, struct slave *slave)
 		/* Find out through which dev should the packet go */
 		memset(&fl6, 0, sizeof(struct flowi6));
 		fl6.daddr = targets[i];
-		fl6.flowi6_oif = bond->dev->ifindex;
 
 		dst = ip6_route_output(dev_net(bond->dev), NULL, &fl6);
 		if (dst->error) {
diff --git a/tools/testing/selftests/drivers/net/bonding/bond_options.sh b/tools/testing/selftests/drivers/net/bonding/bond_options.sh
index 7bc148889ca7..b3eb8a919c71 100755
--- a/tools/testing/selftests/drivers/net/bonding/bond_options.sh
+++ b/tools/testing/selftests/drivers/net/bonding/bond_options.sh
@@ -7,6 +7,7 @@ ALL_TESTS="
 	prio
 	arp_validate
 	num_grat_arp
+	vlan_over_bond
 "
 
 lib_dir=$(dirname "$0")
@@ -376,6 +377,64 @@ num_grat_arp()
 	done
 }
 
+vlan_over_bond_arp()
+{
+	local mode="$1"
+	RET=0
+
+	bond_reset "mode $mode arp_interval 100 arp_ip_target 192.0.3.10"
+	ip -n "${s_ns}" link add bond0.3 link bond0 type vlan id 3
+	ip -n "${s_ns}" link set bond0.3 up
+	ip -n "${s_ns}" addr add 192.0.3.1/24 dev bond0.3
+	ip -n "${s_ns}" addr add 2001:db8::3:1/64 dev bond0.3
+
+	slowwait_for_counter 5 5 tc_rule_handle_stats_get \
+		"dev eth0.3 ingress" 101 ".packets" "-n ${c_ns}" || RET=1
+	log_test "vlan over bond arp" "$mode"
+}
+
+vlan_over_bond_ns()
+{
+	local mode="$1"
+	RET=0
+
+	if skip_ns; then
+		log_test_skip "vlan_over_bond ns" "$mode"
+		return 0
+	fi
+
+	bond_reset "mode $mode arp_interval 100 ns_ip6_target 2001:db8::3:10"
+	ip -n "${s_ns}" link add bond0.3 link bond0 type vlan id 3
+	ip -n "${s_ns}" link set bond0.3 up
+	ip -n "${s_ns}" addr add 192.0.3.1/24 dev bond0.3
+	ip -n "${s_ns}" addr add 2001:db8::3:1/64 dev bond0.3
+
+	slowwait_for_counter 5 5 tc_rule_handle_stats_get \
+		"dev eth0.3 ingress" 102 ".packets" "-n ${c_ns}" || RET=1
+	log_test "vlan over bond ns" "$mode"
+}
+
+vlan_over_bond()
+{
+	# add vlan 3 for client
+	ip -n "${c_ns}" link add eth0.3 link eth0 type vlan id 3
+	ip -n "${c_ns}" link set eth0.3 up
+	ip -n "${c_ns}" addr add 192.0.3.10/24 dev eth0.3
+	ip -n "${c_ns}" addr add 2001:db8::3:10/64 dev eth0.3
+
+	# Add tc rule to check the vlan pkts
+	tc -n "${c_ns}" qdisc add dev eth0.3 clsact
+	tc -n "${c_ns}" filter add dev eth0.3 ingress protocol arp \
+		handle 101 flower skip_hw arp_op request \
+		arp_sip 192.0.3.1 arp_tip 192.0.3.10 action pass
+	tc -n "${c_ns}" filter add dev eth0.3 ingress protocol ipv6 \
+		handle 102 flower skip_hw ip_proto icmpv6 \
+		type 135 src_ip 2001:db8::3:1 action pass
+
+	vlan_over_bond_arp "active-backup"
+	vlan_over_bond_ns "active-backup"
+}
+
 trap cleanup EXIT
 
 setup_prepare
-- 
2.50.1