Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Wait for rcu grace period after releasing netns in ctnetlink,
from Florian Westphal.

2) Incorrect command type in flowtable offload ndo invocation,
from wenxu.

3) Incorrect callback type in flowtable offload flow tuple
updates, also from wenxu.

4) Fix compile warning on flowtable offload infrastructure due to
possible reference to uninitialized variable, from Nathan Chancellor.

5) Do not inline nf_ct_resolve_clash(), this is called from slow
path / stress situations. From Florian Westphal.

6) Missing IPv6 flow selector description in flowtable offload.

7) Missing check for NETDEV_UNREGISTER in nf_tables offload
infrastructure, from wenxu.

8) Update NAT selftest to use randomized netns names, from
Florian Westphal.

9) Restore nfqueue bridge support, from Marco Oliverio.

10) Compilation warning in SCTP_CHUNKMAP_*() on xt_sctp header.
From Phil Sutter.

11) Fix bogus lookup/get match for non-anonymous rbtree sets.

12) Missing netlink validation for NFT_SET_ELEM_INTERVAL_END
elements.

13) Missing netlink validation for NFT_DATA_VALUE after
nft_data_init().

14) If rule specifies no actions, offload infrastructure returns
EOPNOTSUPP.

15) Module refcount leak in object updates.

16) Missing sanitization for ARP traffic from br_netfilter, from
Eric Dumazet.

17) Compilation breakage on big-endian due to incorrect memcpy()
size in the flowtable offload infrastructure.
====================

Signed-off-by: David S. Miller <[e-mail]>

include/uapi/linux/netfilter/xt_sctp.h

···
 #define SCTP_CHUNKMAP_SET(chunkmap, type) 		\
 	do { 						\
 		(chunkmap)[type / bytes(__u32)] |= 	\
-			1 << (type % bytes(__u32));	\
+			1u << (type % bytes(__u32));	\
 	} while (0)
 
 #define SCTP_CHUNKMAP_CLEAR(chunkmap, type)		 	\
 	do {							\
 		(chunkmap)[type / bytes(__u32)] &= 		\
-			~(1 << (type % bytes(__u32)));	\
+			~(1u << (type % bytes(__u32)));	\
 	} while (0)
 
 #define SCTP_CHUNKMAP_IS_SET(chunkmap, type) 			\
 ({								\
 	((chunkmap)[type / bytes (__u32)] & 		\
-		(1 << (type % bytes (__u32)))) ? 1: 0;	\
+		(1u << (type % bytes (__u32)))) ? 1: 0;	\
 })
 
 #define SCTP_CHUNKMAP_RESET(chunkmap) \

net/bridge/br_netfilter_hooks.c

···
 		nf_bridge_pull_encap_header(skb);
 	}
 
+	if (unlikely(!pskb_may_pull(skb, sizeof(struct arphdr))))
+		return NF_DROP;
+
 	if (arp_hdr(skb)->ar_pln != 4) {
 		if (is_vlan_arp(skb, state->net))
 			nf_bridge_push_encap_header(skb);

net/netfilter/nf_conntrack_core.c

···
 }
 
 /* Resolve race on insertion if this protocol allows this. */
-static int nf_ct_resolve_clash(struct net *net, struct sk_buff *skb,
-			       enum ip_conntrack_info ctinfo,
-			       struct nf_conntrack_tuple_hash *h)
+static __cold noinline int
+nf_ct_resolve_clash(struct net *net, struct sk_buff *skb,
+		    enum ip_conntrack_info ctinfo,
+		    struct nf_conntrack_tuple_hash *h)
 {
 	/* This is the conntrack entry already in hashes that won race. */
 	struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);

net/netfilter/nf_conntrack_netlink.c

···
 
 	list_for_each_entry(net, net_exit_list, exit_list)
 		ctnetlink_net_exit(net);
+
+	/* wait for other cpus until they are done with ctnl_notifiers */
+	synchronize_rcu();
 }
 
 static struct pernet_operations ctnetlink_net_ops = {

net/netfilter/nf_flow_table_offload.c

···
 	struct flow_dissector_key_basic			basic;
 	union {
 		struct flow_dissector_key_ipv4_addrs	ipv4;
+		struct flow_dissector_key_ipv6_addrs	ipv6;
 	};
 	struct flow_dissector_key_tcp			tcp;
 	struct flow_dissector_key_ports			tp;
···
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_CONTROL, control);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_BASIC, basic);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4);
+	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_TCP, tcp);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_PORTS, tp);
 
···
 		key->ipv4.dst = tuple->dst_v4.s_addr;
 		mask->ipv4.dst = 0xffffffff;
 		break;
+       case AF_INET6:
+		key->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
+		key->basic.n_proto = htons(ETH_P_IPV6);
+		key->ipv6.src = tuple->src_v6;
+		memset(&mask->ipv6.src, 0xff, sizeof(mask->ipv6.src));
+		key->ipv6.dst = tuple->dst_v6;
+		memset(&mask->ipv6.dst, 0xff, sizeof(mask->ipv6.dst));
+		break;
 	default:
 		return -EOPNOTSUPP;
 	}
+	match->dissector.used_keys |= BIT(key->control.addr_type);
 	mask->basic.n_proto = 0xffff;
 
 	switch (tuple->l4proto) {
···
 
 	match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_CONTROL) |
 				      BIT(FLOW_DISSECTOR_KEY_BASIC) |
-				      BIT(FLOW_DISSECTOR_KEY_IPV4_ADDRS) |
 				      BIT(FLOW_DISSECTOR_KEY_PORTS);
 	return 0;
 }
 
 static void flow_offload_mangle(struct flow_action_entry *entry,
-				enum flow_action_mangle_base htype,
-				u32 offset, u8 *value, u8 *mask)
+				enum flow_action_mangle_base htype, u32 offset,
+				const __be32 *value, const __be32 *mask)
 {
 	entry->id = FLOW_ACTION_MANGLE;
 	entry->mangle.htype = htype;
···
 	memcpy(&val16, dev->dev_addr, 2);
 	val = val16 << 16;
 	flow_offload_mangle(entry0, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 4,
-			    (u8 *)&val, (u8 *)&mask);
+			    &val, &mask);
 
 	mask = ~0xffffffff;
 	memcpy(&val, dev->dev_addr + 2, 4);
 	flow_offload_mangle(entry1, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 8,
-			    (u8 *)&val, (u8 *)&mask);
+			    &val, &mask);
 	dev_put(dev);
 
 	return 0;
···
 	mask = ~0xffffffff;
 	memcpy(&val, n->ha, 4);
 	flow_offload_mangle(entry0, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 0,
-			    (u8 *)&val, (u8 *)&mask);
+			    &val, &mask);
 
 	mask = ~0x0000ffff;
 	memcpy(&val16, n->ha + 4, 2);
 	val = val16;
 	flow_offload_mangle(entry1, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 4,
-			    (u8 *)&val, (u8 *)&mask);
+			    &val, &mask);
 	neigh_release(n);
 
 	return 0;
···
 	}
 
 	flow_offload_mangle(entry, FLOW_ACT_MANGLE_HDR_TYPE_IP4, offset,
-			    (u8 *)&addr, (u8 *)&mask);
+			    &addr, &mask);
 }
 
 static void flow_offload_ipv4_dnat(struct net *net,
···
 	}
 
 	flow_offload_mangle(entry, FLOW_ACT_MANGLE_HDR_TYPE_IP4, offset,
-			    (u8 *)&addr, (u8 *)&mask);
+			    &addr, &mask);
 }
 
 static void flow_offload_ipv6_mangle(struct nf_flow_rule *flow_rule,
 				     unsigned int offset,
-				     u8 *addr, u8 *mask)
+				     const __be32 *addr, const __be32 *mask)
 {
 	struct flow_action_entry *entry;
 	int i;
···
 	for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i += sizeof(u32)) {
 		entry = flow_action_entry_next(flow_rule);
 		flow_offload_mangle(entry, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
-				    offset + i,
-				    &addr[i], mask);
+				    offset + i, &addr[i], mask);
 	}
 }
 
···
 				   struct nf_flow_rule *flow_rule)
 {
 	u32 mask = ~htonl(0xffffffff);
-	const u8 *addr;
+	const __be32 *addr;
 	u32 offset;
 
 	switch (dir) {
 	case FLOW_OFFLOAD_DIR_ORIGINAL:
-		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v6.s6_addr;
+		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v6.s6_addr32;
 		offset = offsetof(struct ipv6hdr, saddr);
 		break;
 	case FLOW_OFFLOAD_DIR_REPLY:
-		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v6.s6_addr;
+		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v6.s6_addr32;
 		offset = offsetof(struct ipv6hdr, daddr);
 		break;
 	default:
 		return;
 	}
 
-	flow_offload_ipv6_mangle(flow_rule, offset, (u8 *)addr, (u8 *)&mask);
+	flow_offload_ipv6_mangle(flow_rule, offset, addr, &mask);
 }
 
 static void flow_offload_ipv6_dnat(struct net *net,
···
 				   struct nf_flow_rule *flow_rule)
 {
 	u32 mask = ~htonl(0xffffffff);
-	const u8 *addr;
+	const __be32 *addr;
 	u32 offset;
 
 	switch (dir) {
 	case FLOW_OFFLOAD_DIR_ORIGINAL:
-		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v6.s6_addr;
+		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v6.s6_addr32;
 		offset = offsetof(struct ipv6hdr, daddr);
 		break;
 	case FLOW_OFFLOAD_DIR_REPLY:
-		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v6.s6_addr;
+		addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v6.s6_addr32;
 		offset = offsetof(struct ipv6hdr, saddr);
 		break;
 	default:
 		return;
 	}
 
-	flow_offload_ipv6_mangle(flow_rule, offset, (u8 *)addr, (u8 *)&mask);
+	flow_offload_ipv6_mangle(flow_rule, offset, addr, &mask);
 }
 
 static int flow_offload_l4proto(const struct flow_offload *flow)
···
 				   struct nf_flow_rule *flow_rule)
 {
 	struct flow_action_entry *entry = flow_action_entry_next(flow_rule);
-	u32 mask = ~htonl(0xffff0000);
-	__be16 port;
+	u32 mask = ~htonl(0xffff0000), port;
 	u32 offset;
 
 	switch (dir) {
 	case FLOW_OFFLOAD_DIR_ORIGINAL:
-		port = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port;
+		port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port);
 		offset = 0; /* offsetof(struct tcphdr, source); */
 		break;
 	case FLOW_OFFLOAD_DIR_REPLY:
-		port = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port;
+		port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port);
 		offset = 0; /* offsetof(struct tcphdr, dest); */
 		break;
 	default:
-		break;
+		return;
 	}
-
+	port = htonl(port << 16);
 	flow_offload_mangle(entry, flow_offload_l4proto(flow), offset,
-			    (u8 *)&port, (u8 *)&mask);
+			    &port, &mask);
 }
 
 static void flow_offload_port_dnat(struct net *net,
···
 				   struct nf_flow_rule *flow_rule)
 {
 	struct flow_action_entry *entry = flow_action_entry_next(flow_rule);
-	u32 mask = ~htonl(0xffff);
-	__be16 port;
+	u32 mask = ~htonl(0xffff), port;
 	u32 offset;
 
 	switch (dir) {
 	case FLOW_OFFLOAD_DIR_ORIGINAL:
-		port = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port;
+		port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port);
 		offset = 0; /* offsetof(struct tcphdr, source); */
 		break;
 	case FLOW_OFFLOAD_DIR_REPLY:
-		port = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port;
+		port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port);
 		offset = 0; /* offsetof(struct tcphdr, dest); */
 		break;
 	default:
-		break;
+		return;
 	}
-
+	port = htonl(port);
 	flow_offload_mangle(entry, flow_offload_l4proto(flow), offset,
-			    (u8 *)&port, (u8 *)&mask);
+			    &port, &mask);
 }
 
 static void flow_offload_ipv4_checksum(struct net *net,
···
 	cls_flow.rule = flow_rule->rule;
 
 	list_for_each_entry(block_cb, &flowtable->flow_block.cb_list, list) {
-		err = block_cb->cb(TC_SETUP_FT, &cls_flow,
+		err = block_cb->cb(TC_SETUP_CLSFLOWER, &cls_flow,
 				   block_cb->cb_priv);
 		if (err < 0)
 			continue;
···
 			     &offload->flow->tuplehash[dir].tuple, &extack);
 
 	list_for_each_entry(block_cb, &flowtable->flow_block.cb_list, list)
-		block_cb->cb(TC_SETUP_FT, &cls_flow, block_cb->cb_priv);
+		block_cb->cb(TC_SETUP_CLSFLOWER, &cls_flow, block_cb->cb_priv);
 
 	offload->flow->flags |= FLOW_OFFLOAD_HW_DEAD;
 }
···
 			     &offload->flow->tuplehash[dir].tuple, &extack);
 
 	list_for_each_entry(block_cb, &flowtable->flow_block.cb_list, list)
-		block_cb->cb(TC_SETUP_FT, &cls_flow, block_cb->cb_priv);
+		block_cb->cb(TC_SETUP_CLSFLOWER, &cls_flow, block_cb->cb_priv);
 	memcpy(stats, &cls_flow.stats, sizeof(*stats));
 }
 
···
 	bo.extack	= &extack;
 	INIT_LIST_HEAD(&bo.cb_list);
 
-	err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
+	err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_FT, &bo);
 	if (err < 0)
 		return err;
 

net/netfilter/nf_queue.c

···
 		goto err;
 	}
 
-	if (!skb_dst_force(skb) && state->hook != NF_INET_PRE_ROUTING) {
+	if (skb_dst(skb) && !skb_dst_force(skb)) {
 		status = -ENETDOWN;
 		goto err;
 	}

net/netfilter/nf_tables_api.c

···
 		return err;
 
 	err = -EINVAL;
-	if (desc.type != NFT_DATA_VALUE || desc.len != set->klen)
+	if (desc.type != NFT_DATA_VALUE || desc.len != set->klen) {
+		nft_data_release(&elem.key.val, desc.type);
 		return err;
+	}
 
 	priv = set->ops->get(ctx->net, set, &elem, flags);
 	if (IS_ERR(priv))
···
 		if (nla[NFTA_SET_ELEM_DATA] == NULL &&
 		    !(flags & NFT_SET_ELEM_INTERVAL_END))
 			return -EINVAL;
-		if (nla[NFTA_SET_ELEM_DATA] != NULL &&
-		    flags & NFT_SET_ELEM_INTERVAL_END)
-			return -EINVAL;
 	} else {
 		if (nla[NFTA_SET_ELEM_DATA] != NULL)
 			return -EINVAL;
 	}
+
+	if ((flags & NFT_SET_ELEM_INTERVAL_END) &&
+	     (nla[NFTA_SET_ELEM_DATA] ||
+	      nla[NFTA_SET_ELEM_OBJREF] ||
+	      nla[NFTA_SET_ELEM_TIMEOUT] ||
+	      nla[NFTA_SET_ELEM_EXPIRATION] ||
+	      nla[NFTA_SET_ELEM_USERDATA] ||
+	      nla[NFTA_SET_ELEM_EXPR]))
+		return -EINVAL;
 
 	timeout = 0;
 	if (nla[NFTA_SET_ELEM_TIMEOUT] != NULL) {
···
 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
 			return -EOPNOTSUPP;
 
-		type = nft_obj_type_get(net, objtype);
+		type = __nft_obj_type_get(objtype);
 		nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
 
 		return nf_tables_updobj(&ctx, type, nla[NFTA_OBJ_DATA], obj);

net/netfilter/nf_tables_offload.c

···
 		expr = nft_expr_next(expr);
 	}
 
+	if (num_actions == 0)
+		return ERR_PTR(-EOPNOTSUPP);
+
 	flow = nft_flow_rule_alloc(num_actions);
 	if (!flow)
 		return ERR_PTR(-ENOMEM);
···
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct net *net = dev_net(dev);
 	struct nft_chain *chain;
+
+	if (event != NETDEV_UNREGISTER)
+		return NOTIFY_DONE;
 
 	mutex_lock(&net->nft.commit_mutex);
 	chain = __nft_offload_get_chain(dev);

net/netfilter/nft_bitwise.c

···
 			    tb[NFTA_BITWISE_MASK]);
 	if (err < 0)
 		return err;
-	if (d1.len != priv->len) {
+	if (d1.type != NFT_DATA_VALUE || d1.len != priv->len) {
 		err = -EINVAL;
 		goto err1;
 	}
···
 			    tb[NFTA_BITWISE_XOR]);
 	if (err < 0)
 		goto err1;
-	if (d2.len != priv->len) {
+	if (d2.type != NFT_DATA_VALUE || d2.len != priv->len) {
 		err = -EINVAL;
 		goto err2;
 	}

net/netfilter/nft_cmp.c

···
 	if (err < 0)
 		return err;
 
+	if (desc.type != NFT_DATA_VALUE) {
+		err = -EINVAL;
+		nft_data_release(&priv->data, desc.type);
+		return err;
+	}
+
 	priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
 	err = nft_validate_register_load(priv->sreg, desc.len);
 	if (err < 0)

net/netfilter/nft_range.c

···
 	if (err < 0)
 		return err;
 
+	if (desc_from.type != NFT_DATA_VALUE) {
+		err = -EINVAL;
+		goto err1;
+	}
+
 	err = nft_data_init(NULL, &priv->data_to, sizeof(priv->data_to),
 			    &desc_to, tb[NFTA_RANGE_TO_DATA]);
 	if (err < 0)
 		goto err1;
+
+	if (desc_to.type != NFT_DATA_VALUE) {
+		err = -EINVAL;
+		goto err2;
+	}
 
 	if (desc_from.len != desc_to.len) {
 		err = -EINVAL;

net/netfilter/nft_set_rbtree.c

···
 				parent = rcu_dereference_raw(parent->rb_left);
 				continue;
 			}
-			if (nft_rbtree_interval_end(rbe))
-				goto out;
+			if (nft_rbtree_interval_end(rbe)) {
+				if (nft_set_is_anonymous(set))
+					return false;
+				parent = rcu_dereference_raw(parent->rb_left);
+				interval = NULL;
+				continue;
+			}
 
 			*ext = &rbe->ext;
 			return true;
···
 		*ext = &interval->ext;
 		return true;
 	}
-out:
+
 	return false;
 }
 
···
 			if (flags & NFT_SET_ELEM_INTERVAL_END)
 				interval = rbe;
 		} else {
-			if (!nft_set_elem_active(&rbe->ext, genmask))
+			if (!nft_set_elem_active(&rbe->ext, genmask)) {
 				parent = rcu_dereference_raw(parent->rb_left);
+				continue;
+			}
 
 			if (!nft_set_ext_exists(&rbe->ext, NFT_SET_EXT_FLAGS) ||
 			    (*nft_set_ext_flags(&rbe->ext) & NFT_SET_ELEM_INTERVAL_END) ==
···
 				*elem = rbe;
 				return true;
 			}
-			return false;
+
+			if (nft_rbtree_interval_end(rbe))
+				interval = NULL;
+
+			parent = rcu_dereference_raw(parent->rb_left);
 		}
 	}
 

tools/testing/selftests/netfilter/nft_nat.sh

···
 ret=0
 test_inet_nat=true
 
+sfx=$(mktemp -u "XXXXXXXX")
+ns0="ns0-$sfx"
+ns1="ns1-$sfx"
+ns2="ns2-$sfx"
+
 cleanup()
 {
-	for i in 0 1 2; do ip netns del ns$i;done
+	for i in 0 1 2; do ip netns del ns$i-"$sfx";done
 }
 
 nft --version > /dev/null 2>&1
···
 	exit $ksft_skip
 fi
 
-ip netns add ns0
+ip netns add "$ns0"
 if [ $? -ne 0 ];then
-	echo "SKIP: Could not create net namespace"
+	echo "SKIP: Could not create net namespace $ns0"
 	exit $ksft_skip
 fi
 
 trap cleanup EXIT
 
-ip netns add ns1
-ip netns add ns2
+ip netns add "$ns1"
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not create net namespace $ns1"
+	exit $ksft_skip
+fi
 
-ip link add veth0 netns ns0 type veth peer name eth0 netns ns1 > /dev/null 2>&1
+ip netns add "$ns2"
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not create net namespace $ns2"
+	exit $ksft_skip
+fi
+
+ip link add veth0 netns "$ns0" type veth peer name eth0 netns "$ns1" > /dev/null 2>&1
 if [ $? -ne 0 ];then
     echo "SKIP: No virtual ethernet pair device support in kernel"
     exit $ksft_skip
 fi
-ip link add veth1 netns ns0 type veth peer name eth0 netns ns2
+ip link add veth1 netns "$ns0" type veth peer name eth0 netns "$ns2"
 
-ip -net ns0 link set lo up
-ip -net ns0 link set veth0 up
-ip -net ns0 addr add 10.0.1.1/24 dev veth0
-ip -net ns0 addr add dead:1::1/64 dev veth0
+ip -net "$ns0" link set lo up
+ip -net "$ns0" link set veth0 up
+ip -net "$ns0" addr add 10.0.1.1/24 dev veth0
+ip -net "$ns0" addr add dead:1::1/64 dev veth0
 
-ip -net ns0 link set veth1 up
-ip -net ns0 addr add 10.0.2.1/24 dev veth1
-ip -net ns0 addr add dead:2::1/64 dev veth1
+ip -net "$ns0" link set veth1 up
+ip -net "$ns0" addr add 10.0.2.1/24 dev veth1
+ip -net "$ns0" addr add dead:2::1/64 dev veth1
 
 for i in 1 2; do
-  ip -net ns$i link set lo up
-  ip -net ns$i link set eth0 up
-  ip -net ns$i addr add 10.0.$i.99/24 dev eth0
-  ip -net ns$i route add default via 10.0.$i.1
-  ip -net ns$i addr add dead:$i::99/64 dev eth0
-  ip -net ns$i route add default via dead:$i::1
+  ip -net ns$i-$sfx link set lo up
+  ip -net ns$i-$sfx link set eth0 up
+  ip -net ns$i-$sfx addr add 10.0.$i.99/24 dev eth0
+  ip -net ns$i-$sfx route add default via 10.0.$i.1
+  ip -net ns$i-$sfx addr add dead:$i::99/64 dev eth0
+  ip -net ns$i-$sfx route add default via dead:$i::1
 done
 
 bad_counter()
···
 	local ns=$1
 	local counter=$2
 	local expect=$3
+	local tag=$4
 
-	echo "ERROR: $counter counter in $ns has unexpected value (expected $expect)" 1>&2
+	echo "ERROR: $counter counter in $ns has unexpected value (expected $expect) at $tag" 1>&2
 	ip netns exec $ns nft list counter inet filter $counter 1>&2
 }
 
···
 
 	cnt=$(ip netns exec $ns nft list counter inet filter ns0in | grep -q "packets 1 bytes 84")
 	if [ $? -ne 0 ]; then
-		bad_counter $ns ns0in "packets 1 bytes 84"
+		bad_counter $ns ns0in "packets 1 bytes 84" "check_counters 1"
 		lret=1
 	fi
 	cnt=$(ip netns exec $ns nft list counter inet filter ns0out | grep -q "packets 1 bytes 84")
 	if [ $? -ne 0 ]; then
-		bad_counter $ns ns0out "packets 1 bytes 84"
+		bad_counter $ns ns0out "packets 1 bytes 84" "check_counters 2"
 		lret=1
 	fi
 
 	expect="packets 1 bytes 104"
 	cnt=$(ip netns exec $ns nft list counter inet filter ns0in6 | grep -q "$expect")
 	if [ $? -ne 0 ]; then
-		bad_counter $ns ns0in6 "$expect"
+		bad_counter $ns ns0in6 "$expect" "check_counters 3"
 		lret=1
 	fi
 	cnt=$(ip netns exec $ns nft list counter inet filter ns0out6 | grep -q "$expect")
 	if [ $? -ne 0 ]; then
-		bad_counter $ns ns0out6 "$expect"
+		bad_counter $ns ns0out6 "$expect" "check_counters 4"
 		lret=1
 	fi
 
···
 	local ns=$1
 	local lret=0
 
-	cnt=$(ip netns exec ns0 nft list counter inet filter ns0in | grep -q "packets 0 bytes 0")
+	cnt=$(ip netns exec "$ns0" nft list counter inet filter ns0in | grep -q "packets 0 bytes 0")
 	if [ $? -ne 0 ]; then
-		bad_counter ns0 ns0in "packets 0 bytes 0"
+		bad_counter "$ns0" ns0in "packets 0 bytes 0" "check_ns0_counters 1"
 		lret=1
 	fi
 
-	cnt=$(ip netns exec ns0 nft list counter inet filter ns0in6 | grep -q "packets 0 bytes 0")
+	cnt=$(ip netns exec "$ns0" nft list counter inet filter ns0in6 | grep -q "packets 0 bytes 0")
 	if [ $? -ne 0 ]; then
-		bad_counter ns0 ns0in6 "packets 0 bytes 0"
+		bad_counter "$ns0" ns0in6 "packets 0 bytes 0"
 		lret=1
 	fi
 
-	cnt=$(ip netns exec ns0 nft list counter inet filter ns0out | grep -q "packets 0 bytes 0")
+	cnt=$(ip netns exec "$ns0" nft list counter inet filter ns0out | grep -q "packets 0 bytes 0")
 	if [ $? -ne 0 ]; then
-		bad_counter ns0 ns0out "packets 0 bytes 0"
+		bad_counter "$ns0" ns0out "packets 0 bytes 0" "check_ns0_counters 2"
 		lret=1
 	fi
-	cnt=$(ip netns exec ns0 nft list counter inet filter ns0out6 | grep -q "packets 0 bytes 0")
+	cnt=$(ip netns exec "$ns0" nft list counter inet filter ns0out6 | grep -q "packets 0 bytes 0")
 	if [ $? -ne 0 ]; then
-		bad_counter ns0 ns0out6 "packets 0 bytes 0"
+		bad_counter "$ns0" ns0out6 "packets 0 bytes 0" "check_ns0_counters3 "
 		lret=1
 	fi
 
 	for dir in "in" "out" ; do
 		expect="packets 1 bytes 84"
-		cnt=$(ip netns exec ns0 nft list counter inet filter ${ns}${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ${ns}${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 $ns$dir "$expect"
+			bad_counter "$ns0" $ns$dir "$expect" "check_ns0_counters 4"
 			lret=1
 		fi
 
 		expect="packets 1 bytes 104"
-		cnt=$(ip netns exec ns0 nft list counter inet filter ${ns}${dir}6 | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ${ns}${dir}6 | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 $ns$dir6 "$expect"
+			bad_counter "$ns0" $ns$dir6 "$expect" "check_ns0_counters 5"
 			lret=1
 		fi
 	done
···
 reset_counters()
 {
 	for i in 0 1 2;do
-		ip netns exec ns$i nft reset counters inet > /dev/null
+		ip netns exec ns$i-$sfx nft reset counters inet > /dev/null
 	done
 }
 
···
 		IPF="ip6"
 	fi
 
-ip netns exec ns0 nft -f - <<EOF
+ip netns exec "$ns0" nft -f /dev/stdin <<EOF
 table $family nat {
 	chain output {
 		type nat hook output priority 0; policy accept;
···
 	fi
 
 	# ping netns1, expect rewrite to netns2
-	ip netns exec ns0 ping -q -c 1 dead:1::99 > /dev/null
+	ip netns exec "$ns0" ping -q -c 1 dead:1::99 > /dev/null
 	if [ $? -ne 0 ]; then
 		lret=1
 		echo "ERROR: ping6 failed"
···
 
 	expect="packets 0 bytes 0"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 ns1$dir "$expect"
+			bad_counter "$ns0" ns1$dir "$expect" "test_local_dnat6 1"
 			lret=1
 		fi
 	done
 
 	expect="packets 1 bytes 104"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 ns2$dir "$expect"
+			bad_counter "$ns0" ns2$dir "$expect" "test_local_dnat6 2"
 			lret=1
 		fi
 	done
···
 	# expect 0 count in ns1
 	expect="packets 0 bytes 0"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_local_dnat6 3"
 			lret=1
 		fi
 	done
···
 	# expect 1 packet in ns2
 	expect="packets 1 bytes 104"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns0$dir "$expect"
+			bad_counter "$ns2" ns0$dir "$expect" "test_local_dnat6 4"
 			lret=1
 		fi
 	done
 
-	test $lret -eq 0 && echo "PASS: ipv6 ping to ns1 was $family NATted to ns2"
-	ip netns exec ns0 nft flush chain ip6 nat output
+	test $lret -eq 0 && echo "PASS: ipv6 ping to $ns1 was $family NATted to $ns2"
+	ip netns exec "$ns0" nft flush chain ip6 nat output
 
 	return $lret
 }
···
 		IPF="ip"
 	fi
 
-ip netns exec ns0 nft -f - <<EOF 2>/dev/null
+ip netns exec "$ns0" nft -f /dev/stdin <<EOF 2>/dev/null
 table $family nat {
 	chain output {
 		type nat hook output priority 0; policy accept;
···
 	fi
 
 	# ping netns1, expect rewrite to netns2
-	ip netns exec ns0 ping -q -c 1 10.0.1.99 > /dev/null
+	ip netns exec "$ns0" ping -q -c 1 10.0.1.99 > /dev/null
 	if [ $? -ne 0 ]; then
 		lret=1
 		echo "ERROR: ping failed"
···
 
 	expect="packets 0 bytes 0"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 ns1$dir "$expect"
+			bad_counter "$ns0" ns1$dir "$expect" "test_local_dnat 1"
 			lret=1
 		fi
 	done
 
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 ns2$dir "$expect"
+			bad_counter "$ns0" ns2$dir "$expect" "test_local_dnat 2"
 			lret=1
 		fi
 	done
···
 	# expect 0 count in ns1
 	expect="packets 0 bytes 0"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_local_dnat 3"
 			lret=1
 		fi
 	done
···
 	# expect 1 packet in ns2
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns0$dir "$expect"
+			bad_counter "$ns2" ns0$dir "$expect" "test_local_dnat 4"
 			lret=1
 		fi
 	done
 
-	test $lret -eq 0 && echo "PASS: ping to ns1 was $family NATted to ns2"
+	test $lret -eq 0 && echo "PASS: ping to $ns1 was $family NATted to $ns2"
 
-	ip netns exec ns0 nft flush chain $family nat output
+	ip netns exec "$ns0" nft flush chain $family nat output
 
 	reset_counters
-	ip netns exec ns0 ping -q -c 1 10.0.1.99 > /dev/null
+	ip netns exec "$ns0" ping -q -c 1 10.0.1.99 > /dev/null
 	if [ $? -ne 0 ]; then
 		lret=1
 		echo "ERROR: ping failed"
···
 
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns1$dir "$expect"
+			bad_counter "$ns1" ns1$dir "$expect" "test_local_dnat 5"
 			lret=1
 		fi
 	done
 	expect="packets 0 bytes 0"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 ns2$dir "$expect"
+			bad_counter "$ns0" ns2$dir "$expect" "test_local_dnat 6"
 			lret=1
 		fi
 	done
···
 	# expect 1 count in ns1
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns0 ns0$dir "$expect"
+			bad_counter "$ns0" ns0$dir "$expect" "test_local_dnat 7"
 			lret=1
 		fi
 	done
···
 	# expect 0 packet in ns2
 	expect="packets 0 bytes 0"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns2$dir "$expect"
+			bad_counter "$ns2" ns0$dir "$expect" "test_local_dnat 8"
 			lret=1
 		fi
 	done
 
-	test $lret -eq 0 && echo "PASS: ping to ns1 OK after $family nat output chain flush"
+	test $lret -eq 0 && echo "PASS: ping to $ns1 OK after $family nat output chain flush"
 
 	return $lret
 }
···
 	local natflags=$2
 	local lret=0
 
-	ip netns exec ns0 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
+	ip netns exec "$ns0" sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
 
-	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 via ipv6"
+		echo "ERROR: cannot ping $ns1 from $ns2 via ipv6"
 		return 1
 		lret=1
 	fi
 
 	expect="packets 1 bytes 104"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns2$dir "$expect"
+			bad_counter "$ns1" ns2$dir "$expect" "test_masquerade6 1"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns2" ns1$dir "$expect" "test_masquerade6 2"
 			lret=1
 		fi
 	done
···
 	reset_counters
 
 # add masquerading rule
-ip netns exec ns0 nft -f - <<EOF
+ip netns exec "$ns0" nft -f /dev/stdin <<EOF
 table $family nat {
 	chain postrouting {
 		type nat hook postrouting priority 0; policy accept;
···
 		return $ksft_skip
 	fi
 
-	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 with active $family masquerade $natflags"
+		echo "ERROR: cannot ping $ns1 from $ns2 with active $family masquerade $natflags"
 		lret=1
 	fi
 
 	# ns1 should have seen packets from ns0, due to masquerade
 	expect="packets 1 bytes 104"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_masquerade6 3"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns2" ns1$dir "$expect" "test_masquerade6 4"
 			lret=1
 		fi
 	done
···
 	# ns1 should not have seen packets from ns2, due to masquerade
 	expect="packets 0 bytes 0"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_masquerade6 5"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns0" ns1$dir "$expect" "test_masquerade6 6"
 			lret=1
 		fi
 	done
 
-	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 with active ipv6 masquerade $natflags (attempt 2)"
+		echo "ERROR: cannot ping $ns1 from $ns2 with active ipv6 masquerade $natflags (attempt 2)"
 		lret=1
 	fi
 
-	ip netns exec ns0 nft flush chain $family nat postrouting
+	ip netns exec "$ns0" nft flush chain $family nat postrouting
 	if [ $? -ne 0 ]; then
 		echo "ERROR: Could not flush $family nat postrouting" 1>&2
 		lret=1
 	fi
 
-	test $lret -eq 0 && echo "PASS: $family IPv6 masquerade $natflags for ns2"
+	test $lret -eq 0 && echo "PASS: $family IPv6 masquerade $natflags for $ns2"
 
 	return $lret
 }
···
 	local natflags=$2
 	local lret=0
 
-	ip netns exec ns0 sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
-	ip netns exec ns0 sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null
+	ip netns exec "$ns0" sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
+	ip netns exec "$ns0" sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null
 
-	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 $natflags"
+		echo "ERROR: cannot ping $ns1 from "$ns2" $natflags"
 		lret=1
 	fi
 
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns2$dir "$expect"
+			bad_counter "$ns1" ns2$dir "$expect" "test_masquerade 1"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns2" ns1$dir "$expect" "test_masquerade 2"
 			lret=1
 		fi
 	done
···
 	reset_counters
 
 # add masquerading rule
-ip netns exec ns0 nft -f - <<EOF
+ip netns exec "$ns0" nft -f /dev/stdin <<EOF
 table $family nat {
 	chain postrouting {
 		type nat hook postrouting priority 0; policy accept;
···
 		return $ksft_skip
 	fi
 
-	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 with active $family masquerade $natflags"
+		echo "ERROR: cannot ping $ns1 from $ns2 with active $family masquerade $natflags"
 		lret=1
 	fi
 
 	# ns1 should have seen packets from ns0, due to masquerade
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns0${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_masquerade 3"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns2" ns1$dir "$expect" "test_masquerade 4"
 			lret=1
 		fi
 	done
···
 	# ns1 should not have seen packets from ns2, due to masquerade
 	expect="packets 0 bytes 0"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_masquerade 5"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns0" ns1$dir "$expect" "test_masquerade 6"
 			lret=1
 		fi
 	done
 
-	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 with active ip masquerade $natflags (attempt 2)"
+		echo "ERROR: cannot ping $ns1 from $ns2 with active ip masquerade $natflags (attempt 2)"
 		lret=1
 	fi
 
-	ip netns exec ns0 nft flush chain $family nat postrouting
+	ip netns exec "$ns0" nft flush chain $family nat postrouting
 	if [ $? -ne 0 ]; then
 		echo "ERROR: Could not flush $family nat postrouting" 1>&2
 		lret=1
 	fi
 
-	test $lret -eq 0 && echo "PASS: $family IP masquerade $natflags for ns2"
+	test $lret -eq 0 && echo "PASS: $family IP masquerade $natflags for $ns2"
 
 	return $lret
 }
···
 	local family=$1
 	local lret=0
 
-	ip netns exec ns0 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
+	ip netns exec "$ns0" sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
 
-	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannnot ping ns1 from ns2 via ipv6"
+		echo "ERROR: cannnot ping $ns1 from $ns2 via ipv6"
 		lret=1
 	fi
 
 	expect="packets 1 bytes 104"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns2$dir "$expect"
+			bad_counter "$ns1" ns2$dir "$expect" "test_redirect6 1"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns2" ns1$dir "$expect" "test_redirect6 2"
 			lret=1
 		fi
 	done
···
 	reset_counters
 
 # add redirect rule
-ip netns exec ns0 nft -f - <<EOF
+ip netns exec "$ns0" nft -f /dev/stdin <<EOF
 table $family nat {
 	chain prerouting {
 		type nat hook prerouting priority 0; policy accept;
···
 		return $ksft_skip
 	fi
 
-	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 via ipv6 with active $family redirect"
+		echo "ERROR: cannot ping $ns1 from $ns2 via ipv6 with active $family redirect"
 		lret=1
 	fi
 
 	# ns1 should have seen no packets from ns2, due to redirection
 	expect="packets 0 bytes 0"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_redirect6 3"
 			lret=1
 		fi
 	done
···
 	# ns0 should have seen packets from ns2, due to masquerade
 	expect="packets 1 bytes 104"
 	for dir in "in6" "out6" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_redirect6 4"
 			lret=1
 		fi
 	done
 
-	ip netns exec ns0 nft delete table $family nat
+	ip netns exec "$ns0" nft delete table $family nat
 	if [ $? -ne 0 ]; then
 		echo "ERROR: Could not delete $family nat table" 1>&2
 		lret=1
 	fi
 
-	test $lret -eq 0 && echo "PASS: $family IPv6 redirection for ns2"
+	test $lret -eq 0 && echo "PASS: $family IPv6 redirection for $ns2"
 
 	return $lret
 }
···
 	local family=$1
 	local lret=0
 
-	ip netns exec ns0 sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
-	ip netns exec ns0 sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null
+	ip netns exec "$ns0" sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
+	ip netns exec "$ns0" sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null
 
-	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2"
+		echo "ERROR: cannot ping $ns1 from $ns2"
 		lret=1
 	fi
 
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns2$dir "$expect"
+			bad_counter "$ns1" $ns2$dir "$expect" "test_redirect 1"
 			lret=1
 		fi
 
-		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns2" nft list counter inet filter ns1${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns2 ns1$dir "$expect"
+			bad_counter "$ns2" ns1$dir "$expect" "test_redirect 2"
 			lret=1
 		fi
 	done
···
 	reset_counters
 
 # add redirect rule
-ip netns exec ns0 nft -f - <<EOF
+ip netns exec "$ns0" nft -f /dev/stdin <<EOF
 table $family nat {
 	chain prerouting {
 		type nat hook prerouting priority 0; policy accept;
···
 		return $ksft_skip
 	fi
 
-	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
+	ip netns exec "$ns2" ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
 	if [ $? -ne 0 ] ; then
-		echo "ERROR: cannot ping ns1 from ns2 with active $family ip redirect"
+		echo "ERROR: cannot ping $ns1 from $ns2 with active $family ip redirect"
 		lret=1
 	fi
 
···
 	expect="packets 0 bytes 0"
 	for dir in "in" "out" ; do
 
-		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns1" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns1" ns0$dir "$expect" "test_redirect 3"
 			lret=1
 		fi
 	done
···
 	# ns0 should have seen packets from ns2, due to masquerade
 	expect="packets 1 bytes 84"
 	for dir in "in" "out" ; do
-		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
+		cnt=$(ip netns exec "$ns0" nft list counter inet filter ns2${dir} | grep -q "$expect")
 		if [ $? -ne 0 ]; then
-			bad_counter ns1 ns0$dir "$expect"
+			bad_counter "$ns0" ns0$dir "$expect" "test_redirect 4"
 			lret=1
 		fi
 	done
 
-	ip netns exec ns0 nft delete table $family nat
+	ip netns exec "$ns0" nft delete table $family nat
 	if [ $? -ne 0 ]; then
 		echo "ERROR: Could not delete $family nat table" 1>&2
 		lret=1
 	fi
 
-	test $lret -eq 0 && echo "PASS: $family IP redirection for ns2"
+	test $lret -eq 0 && echo "PASS: $family IP redirection for $ns2"
 
 	return $lret
 }
 
 
-# ip netns exec ns0 ping -c 1 -q 10.0.$i.99
+# ip netns exec "$ns0" ping -c 1 -q 10.0.$i.99
 for i in 0 1 2; do
-ip netns exec ns$i nft -f - <<EOF
+ip netns exec ns$i-$sfx nft -f /dev/stdin <<EOF
 table inet filter {
 	counter ns0in {}
 	counter ns1in {}
···
 sleep 3
 # test basic connectivity
 for i in 1 2; do
-  ip netns exec ns0 ping -c 1 -q 10.0.$i.99 > /dev/null
+  ip netns exec "$ns0" ping -c 1 -q 10.0.$i.99 > /dev/null
   if [ $? -ne 0 ];then
   	echo "ERROR: Could not reach other namespace(s)" 1>&2
 	ret=1
   fi
 
-  ip netns exec ns0 ping -c 1 -q dead:$i::99 > /dev/null
+  ip netns exec "$ns0" ping -c 1 -q dead:$i::99 > /dev/null
   if [ $? -ne 0 ];then
 	echo "ERROR: Could not reach other namespace(s) via ipv6" 1>&2
 	ret=1
   fi
-  check_counters ns$i
+  check_counters ns$i-$sfx
   if [ $? -ne 0 ]; then
 	ret=1
   fi
···
 done
 
 if [ $ret -eq 0 ];then
-	echo "PASS: netns routing/connectivity: ns0 can reach ns1 and ns2"
+	echo "PASS: netns routing/connectivity: $ns0 can reach $ns1 and $ns2"
 fi
 
 reset_counters
···
 reset_counters
 $test_inet_nat && test_redirect inet
 $test_inet_nat && test_redirect6 inet
+
+if [ $ret -ne 0 ];then
+	echo -n "FAIL: "
+	nft --version
+fi
 
 exit $ret