Merge branch 'bonding-fix-ns-targets-not-work-on-hardware-nic'

Hangbin Liu says:

====================
bonding: fix ns targets not work on hardware NIC

The first patch fixed ns targets not work on hardware NIC when bonding
set arp_validate.

The second patch add a related selftest for bonding.

v4: Thanks Nikolay for the comments:
    use bond_slave_ns_maddrs_{add/del} with clear name
    fix comments typos
    remove _slave_set_ns_maddrs underscore directly
    update bond_option_arp_validate_set() change logic
v3: use ndisc_mc_map to convert the mcast mac address (Jay Vosburgh)
v2: only add/del mcast group on backup slaves when arp_validate is set (Jay Vosburgh)
    arp_validate doesn't support 3ad, tlb, alb. So let's only do it on ab mode.
====================

Link: https://patch.msgid.link/20241111101650.27685-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

4 files changed, 151 insertions, 3 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index b1bffd8e9a95..15e0f14d0d49 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1008,6 +1008,8 @@ static void bond_hw_addr_swap(struct bonding *bond, struct slave *new_active,
 
 		if (bond->dev->flags & IFF_UP)
 			bond_hw_addr_flush(bond->dev, old_active->dev);
+
+		bond_slave_ns_maddrs_add(bond, old_active);
 	}
 
 	if (new_active) {
@@ -1024,6 +1026,8 @@ static void bond_hw_addr_swap(struct bonding *bond, struct slave *new_active,
 			dev_mc_sync(new_active->dev, bond->dev);
 			netif_addr_unlock_bh(bond->dev);
 		}
+
+		bond_slave_ns_maddrs_del(bond, new_active);
 	}
 }
 
@@ -2341,6 +2345,11 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 	bond_compute_features(bond);
 	bond_set_carrier(bond);
 
+	/* Needs to be called before bond_select_active_slave(), which will
+	 * remove the maddrs if the slave is selected as active slave.
+	 */
+	bond_slave_ns_maddrs_add(bond, new_slave);
+
 	if (bond_uses_primary(bond)) {
 		block_netpoll_tx();
 		bond_select_active_slave(bond);
@@ -2350,7 +2359,6 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 	if (bond_mode_can_use_xmit_hash(bond))
 		bond_update_slave_arr(bond, NULL);
 
-
 	if (!slave_dev->netdev_ops->ndo_bpf ||
 	    !slave_dev->netdev_ops->ndo_xdp_xmit) {
 		if (bond->xdp_prog) {
@@ -2548,6 +2556,12 @@ static int __bond_release_one(struct net_device *bond_dev,
 	if (oldcurrent == slave)
 		bond_change_active_slave(bond, NULL);
 
+	/* Must be called after bond_change_active_slave () as the slave
+	 * might change from an active slave to a backup slave. Then it is
+	 * necessary to clear the maddrs on the backup slave.
+	 */
+	bond_slave_ns_maddrs_del(bond, slave);
+
 	if (bond_is_lb(bond)) {
 		/* Must be called only after the slave has been
 		 * detached from the list and the curr_active_slave
diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index 95d59a18c022..327b6ecdc77e 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -15,6 +15,7 @@
 #include <linux/sched/signal.h>
 
 #include <net/bonding.h>
+#include <net/ndisc.h>
 
 static int bond_option_active_slave_set(struct bonding *bond,
 					const struct bond_opt_value *newval);
@@ -1234,6 +1235,68 @@ static int bond_option_arp_ip_targets_set(struct bonding *bond,
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
+static bool slave_can_set_ns_maddr(const struct bonding *bond, struct slave *slave)
+{
+	return BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP &&
+	       !bond_is_active_slave(slave) &&
+	       slave->dev->flags & IFF_MULTICAST;
+}
+
+static void slave_set_ns_maddrs(struct bonding *bond, struct slave *slave, bool add)
+{
+	struct in6_addr *targets = bond->params.ns_targets;
+	char slot_maddr[MAX_ADDR_LEN];
+	int i;
+
+	if (!slave_can_set_ns_maddr(bond, slave))
+		return;
+
+	for (i = 0; i < BOND_MAX_NS_TARGETS; i++) {
+		if (ipv6_addr_any(&targets[i]))
+			break;
+
+		if (!ndisc_mc_map(&targets[i], slot_maddr, slave->dev, 0)) {
+			if (add)
+				dev_mc_add(slave->dev, slot_maddr);
+			else
+				dev_mc_del(slave->dev, slot_maddr);
+		}
+	}
+}
+
+void bond_slave_ns_maddrs_add(struct bonding *bond, struct slave *slave)
+{
+	if (!bond->params.arp_validate)
+		return;
+	slave_set_ns_maddrs(bond, slave, true);
+}
+
+void bond_slave_ns_maddrs_del(struct bonding *bond, struct slave *slave)
+{
+	if (!bond->params.arp_validate)
+		return;
+	slave_set_ns_maddrs(bond, slave, false);
+}
+
+static void slave_set_ns_maddr(struct bonding *bond, struct slave *slave,
+			       struct in6_addr *target, struct in6_addr *slot)
+{
+	char target_maddr[MAX_ADDR_LEN], slot_maddr[MAX_ADDR_LEN];
+
+	if (!bond->params.arp_validate || !slave_can_set_ns_maddr(bond, slave))
+		return;
+
+	/* remove the previous maddr from slave */
+	if (!ipv6_addr_any(slot) &&
+	    !ndisc_mc_map(slot, slot_maddr, slave->dev, 0))
+		dev_mc_del(slave->dev, slot_maddr);
+
+	/* add new maddr on slave if target is set */
+	if (!ipv6_addr_any(target) &&
+	    !ndisc_mc_map(target, target_maddr, slave->dev, 0))
+		dev_mc_add(slave->dev, target_maddr);
+}
+
 static void _bond_options_ns_ip6_target_set(struct bonding *bond, int slot,
 					    struct in6_addr *target,
 					    unsigned long last_rx)
@@ -1243,8 +1306,10 @@ static void _bond_options_ns_ip6_target_set(struct bonding *bond, int slot,
 	struct slave *slave;
 
 	if (slot >= 0 && slot < BOND_MAX_NS_TARGETS) {
-		bond_for_each_slave(bond, slave, iter)
+		bond_for_each_slave(bond, slave, iter) {
 			slave->target_last_arp_rx[slot] = last_rx;
+			slave_set_ns_maddr(bond, slave, target, &targets[slot]);
+		}
 		targets[slot] = *target;
 	}
 }
@@ -1296,15 +1361,30 @@ static int bond_option_ns_ip6_targets_set(struct bonding *bond,
 {
 	return -EPERM;
 }
+
+static void slave_set_ns_maddrs(struct bonding *bond, struct slave *slave, bool add) {}
+
+void bond_slave_ns_maddrs_add(struct bonding *bond, struct slave *slave) {}
+
+void bond_slave_ns_maddrs_del(struct bonding *bond, struct slave *slave) {}
 #endif
 
 static int bond_option_arp_validate_set(struct bonding *bond,
 					const struct bond_opt_value *newval)
 {
+	bool changed = !!bond->params.arp_validate != !!newval->value;
+	struct list_head *iter;
+	struct slave *slave;
+
 	netdev_dbg(bond->dev, "Setting arp_validate to %s (%llu)\n",
 		   newval->string, newval->value);
 	bond->params.arp_validate = newval->value;
 
+	if (changed) {
+		bond_for_each_slave(bond, slave, iter)
+			slave_set_ns_maddrs(bond, slave, !!bond->params.arp_validate);
+	}
+
 	return 0;
 }
 
diff --git a/include/net/bond_options.h b/include/net/bond_options.h
index 473a0147769e..18687ccf0638 100644
--- a/include/net/bond_options.h
+++ b/include/net/bond_options.h
@@ -161,5 +161,7 @@ void bond_option_arp_ip_targets_clear(struct bonding *bond);
 #if IS_ENABLED(CONFIG_IPV6)
 void bond_option_ns_ip6_targets_clear(struct bonding *bond);
 #endif
+void bond_slave_ns_maddrs_add(struct bonding *bond, struct slave *slave);
+void bond_slave_ns_maddrs_del(struct bonding *bond, struct slave *slave);
 
 #endif /* _NET_BOND_OPTIONS_H */
diff --git a/tools/testing/selftests/drivers/net/bonding/bond_options.sh b/tools/testing/selftests/drivers/net/bonding/bond_options.sh
index 41d0859feb7d..edc56e2cc606 100755
--- a/tools/testing/selftests/drivers/net/bonding/bond_options.sh
+++ b/tools/testing/selftests/drivers/net/bonding/bond_options.sh
@@ -11,6 +11,8 @@ ALL_TESTS="
 
 lib_dir=$(dirname "$0")
 source ${lib_dir}/bond_topo_3d1c.sh
+c_maddr="33:33:00:00:00:10"
+g_maddr="33:33:00:00:02:54"
 
 skip_prio()
 {
@@ -240,6 +242,54 @@ arp_validate_test()
 	done
 }
 
+# Testing correct multicast groups are added to slaves for ns targets
+arp_validate_mcast()
+{
+	RET=0
+	local arp_valid=$(cmd_jq "ip -n ${s_ns} -j -d link show bond0" ".[].linkinfo.info_data.arp_validate")
+	local active_slave=$(cmd_jq "ip -n ${s_ns} -d -j link show bond0" ".[].linkinfo.info_data.active_slave")
+
+	for i in $(seq 0 2); do
+		maddr_list=$(ip -n ${s_ns} maddr show dev eth${i})
+
+		# arp_valid == 0 or active_slave should not join any maddrs
+		if { [ "$arp_valid" == "null" ] || [ "eth${i}" == ${active_slave} ]; } && \
+			echo "$maddr_list" | grep -qE "${c_maddr}|${g_maddr}"; then
+			RET=1
+			check_err 1 "arp_valid $arp_valid active_slave $active_slave, eth$i has mcast group"
+		# arp_valid != 0 and backup_slave should join both maddrs
+		elif [ "$arp_valid" != "null" ] && [ "eth${i}" != ${active_slave} ] && \
+		     ( ! echo "$maddr_list" | grep -q "${c_maddr}" || \
+		       ! echo "$maddr_list" | grep -q "${m_maddr}"); then
+			RET=1
+			check_err 1 "arp_valid $arp_valid active_slave $active_slave, eth$i has mcast group"
+		fi
+	done
+
+	# Do failover
+	ip -n ${s_ns} link set ${active_slave} down
+	# wait for active link change
+	slowwait 2 active_slave_changed $active_slave
+	active_slave=$(cmd_jq "ip -n ${s_ns} -d -j link show bond0" ".[].linkinfo.info_data.active_slave")
+
+	for i in $(seq 0 2); do
+		maddr_list=$(ip -n ${s_ns} maddr show dev eth${i})
+
+		# arp_valid == 0 or active_slave should not join any maddrs
+		if { [ "$arp_valid" == "null" ] || [ "eth${i}" == ${active_slave} ]; } && \
+			echo "$maddr_list" | grep -qE "${c_maddr}|${g_maddr}"; then
+			RET=1
+			check_err 1 "arp_valid $arp_valid active_slave $active_slave, eth$i has mcast group"
+		# arp_valid != 0 and backup_slave should join both maddrs
+		elif [ "$arp_valid" != "null" ] && [ "eth${i}" != ${active_slave} ] && \
+		     ( ! echo "$maddr_list" | grep -q "${c_maddr}" || \
+		       ! echo "$maddr_list" | grep -q "${m_maddr}"); then
+			RET=1
+			check_err 1 "arp_valid $arp_valid active_slave $active_slave, eth$i has mcast group"
+		fi
+	done
+}
+
 arp_validate_arp()
 {
 	local mode=$1
@@ -261,8 +311,10 @@ arp_validate_ns()
 	fi
 
 	for val in $(seq 0 6); do
-		arp_validate_test "mode $mode arp_interval 100 ns_ip6_target ${g_ip6} arp_validate $val"
+		arp_validate_test "mode $mode arp_interval 100 ns_ip6_target ${g_ip6},${c_ip6} arp_validate $val"
 		log_test "arp_validate" "$mode ns_ip6_target arp_validate $val"
+		arp_validate_mcast
+		log_test "arp_validate" "join mcast group"
 	done
 }