1 files changed, 217 insertions, 156 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 0e4502d641eb..eea5ed09e1bb 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -54,6 +54,8 @@
 #include <net/rtnetlink.h>
 #include <net/net_namespace.h>
 
+#include "dev.h"
+
 #define RTNL_MAX_TYPE		50
 #define RTNL_SLAVE_MAX_TYPE	40
 
@@ -247,6 +249,8 @@ static int rtnl_register_internal(struct module *owner,
 	if (dumpit)
 		link->dumpit = dumpit;
 
+	WARN_ON(rtnl_msgtype_kind(msgtype) != RTNL_KIND_DEL &&
+		(flags & RTNL_FLAG_BULK_DEL_SUPPORTED));
 	link->flags |= flags;
 
 	/* publish protocol:msgtype */
@@ -2640,17 +2644,23 @@ static int do_set_proto_down(struct net_device *dev,
 static int do_setlink(const struct sk_buff *skb,
 		      struct net_device *dev, struct ifinfomsg *ifm,
 		      struct netlink_ext_ack *extack,
-		      struct nlattr **tb, char *ifname, int status)
+		      struct nlattr **tb, int status)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
+	char ifname[IFNAMSIZ];
 	int err;
 
 	err = validate_linkmsg(dev, tb, extack);
 	if (err < 0)
 		return err;
 
+	if (tb[IFLA_IFNAME])
+		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+	else
+		ifname[0] = '\0';
+
 	if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD] || tb[IFLA_TARGET_NETNSID]) {
-		const char *pat = ifname && ifname[0] ? ifname : NULL;
+		const char *pat = ifname[0] ? ifname : NULL;
 		struct net *net;
 		int new_ifindex;
 
@@ -3006,21 +3016,16 @@ errout:
 }
 
 static struct net_device *rtnl_dev_get(struct net *net,
-				       struct nlattr *ifname_attr,
-				       struct nlattr *altifname_attr,
-				       char *ifname)
-{
-	char buffer[ALTIFNAMSIZ];
-
-	if (!ifname) {
-		ifname = buffer;
-		if (ifname_attr)
-			nla_strscpy(ifname, ifname_attr, IFNAMSIZ);
-		else if (altifname_attr)
-			nla_strscpy(ifname, altifname_attr, ALTIFNAMSIZ);
-		else
-			return NULL;
-	}
+				       struct nlattr *tb[])
+{
+	char ifname[ALTIFNAMSIZ];
+
+	if (tb[IFLA_IFNAME])
+		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+	else if (tb[IFLA_ALT_IFNAME])
+		nla_strscpy(ifname, tb[IFLA_ALT_IFNAME], ALTIFNAMSIZ);
+	else
+		return NULL;
 
 	return __dev_get_by_name(net, ifname);
 }
@@ -3033,7 +3038,6 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct net_device *dev;
 	int err;
 	struct nlattr *tb[IFLA_MAX+1];
-	char ifname[IFNAMSIZ];
 
 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFLA_MAX,
 				     ifla_policy, extack);
@@ -3044,17 +3048,12 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (err < 0)
 		goto errout;
 
-	if (tb[IFLA_IFNAME])
-		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
-	else
-		ifname[0] = '\0';
-
 	err = -EINVAL;
 	ifm = nlmsg_data(nlh);
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(net, ifm->ifi_index);
 	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
-		dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname);
+		dev = rtnl_dev_get(net, tb);
 	else
 		goto errout;
 
@@ -3063,7 +3062,7 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 		goto errout;
 	}
 
-	err = do_setlink(skb, dev, ifm, extack, tb, ifname, 0);
+	err = do_setlink(skb, dev, ifm, extack, tb, 0);
 errout:
 	return err;
 }
@@ -3152,15 +3151,14 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(tgt_net, ifm->ifi_index);
 	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
-		dev = rtnl_dev_get(net, tb[IFLA_IFNAME],
-				   tb[IFLA_ALT_IFNAME], NULL);
+		dev = rtnl_dev_get(net, tb);
 	else if (tb[IFLA_GROUP])
 		err = rtnl_group_dellink(tgt_net, nla_get_u32(tb[IFLA_GROUP]));
 	else
 		goto out;
 
 	if (!dev) {
-		if (tb[IFLA_IFNAME] || ifm->ifi_index > 0)
+		if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME] || ifm->ifi_index > 0)
 			err = -ENODEV;
 
 		goto out;
@@ -3295,7 +3293,7 @@ static int rtnl_group_changelink(const struct sk_buff *skb,
 
 	for_each_netdev_safe(net, dev, aux) {
 		if (dev->group == group) {
-			err = do_setlink(skb, dev, ifm, extack, tb, NULL, 0);
+			err = do_setlink(skb, dev, ifm, extack, tb, 0);
 			if (err < 0)
 				return err;
 		}
@@ -3304,24 +3302,118 @@ static int rtnl_group_changelink(const struct sk_buff *skb,
 	return 0;
 }
 
-static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
-			  struct nlattr **attr, struct netlink_ext_ack *extack)
+static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
+			       const struct rtnl_link_ops *ops,
+			       struct nlattr **tb, struct nlattr **data,
+			       struct netlink_ext_ack *extack)
 {
-	struct nlattr *slave_attr[RTNL_SLAVE_MAX_TYPE + 1];
 	unsigned char name_assign_type = NET_NAME_USER;
+	struct net *net = sock_net(skb->sk);
+	struct net *dest_net, *link_net;
+	struct net_device *dev;
+	char ifname[IFNAMSIZ];
+	int err;
+
+	if (!ops->alloc && !ops->setup)
+		return -EOPNOTSUPP;
+
+	if (tb[IFLA_IFNAME]) {
+		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+	} else {
+		snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
+		name_assign_type = NET_NAME_ENUM;
+	}
+
+	dest_net = rtnl_link_get_net_capable(skb, net, tb, CAP_NET_ADMIN);
+	if (IS_ERR(dest_net))
+		return PTR_ERR(dest_net);
+
+	if (tb[IFLA_LINK_NETNSID]) {
+		int id = nla_get_s32(tb[IFLA_LINK_NETNSID]);
+
+		link_net = get_net_ns_by_id(dest_net, id);
+		if (!link_net) {
+			NL_SET_ERR_MSG(extack, "Unknown network namespace id");
+			err =  -EINVAL;
+			goto out;
+		}
+		err = -EPERM;
+		if (!netlink_ns_capable(skb, link_net->user_ns, CAP_NET_ADMIN))
+			goto out;
+	} else {
+		link_net = NULL;
+	}
+
+	dev = rtnl_create_link(link_net ? : dest_net, ifname,
+			       name_assign_type, ops, tb, extack);
+	if (IS_ERR(dev)) {
+		err = PTR_ERR(dev);
+		goto out;
+	}
+
+	dev->ifindex = ifm->ifi_index;
+
+	if (ops->newlink)
+		err = ops->newlink(link_net ? : net, dev, tb, data, extack);
+	else
+		err = register_netdevice(dev);
+	if (err < 0) {
+		free_netdev(dev);
+		goto out;
+	}
+
+	err = rtnl_configure_link(dev, ifm);
+	if (err < 0)
+		goto out_unregister;
+	if (link_net) {
+		err = dev_change_net_namespace(dev, dest_net, ifname);
+		if (err < 0)
+			goto out_unregister;
+	}
+	if (tb[IFLA_MASTER]) {
+		err = do_set_master(dev, nla_get_u32(tb[IFLA_MASTER]), extack);
+		if (err)
+			goto out_unregister;
+	}
+out:
+	if (link_net)
+		put_net(link_net);
+	put_net(dest_net);
+	return err;
+out_unregister:
+	if (ops->newlink) {
+		LIST_HEAD(list_kill);
+
+		ops->dellink(dev, &list_kill);
+		unregister_netdevice_many(&list_kill);
+	} else {
+		unregister_netdevice(dev);
+	}
+	goto out;
+}
+
+struct rtnl_newlink_tbs {
+	struct nlattr *tb[IFLA_MAX + 1];
+	struct nlattr *attr[RTNL_MAX_TYPE + 1];
+	struct nlattr *slave_attr[RTNL_SLAVE_MAX_TYPE + 1];
+};
+
+static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
+			  struct rtnl_newlink_tbs *tbs,
+			  struct netlink_ext_ack *extack)
+{
 	struct nlattr *linkinfo[IFLA_INFO_MAX + 1];
+	struct nlattr ** const tb = tbs->tb;
 	const struct rtnl_link_ops *m_ops;
 	struct net_device *master_dev;
 	struct net *net = sock_net(skb->sk);
 	const struct rtnl_link_ops *ops;
-	struct nlattr *tb[IFLA_MAX + 1];
-	struct net *dest_net, *link_net;
 	struct nlattr **slave_data;
 	char kind[MODULE_NAME_LEN];
 	struct net_device *dev;
 	struct ifinfomsg *ifm;
-	char ifname[IFNAMSIZ];
 	struct nlattr **data;
+	bool link_specified;
 	int err;
 
 #ifdef CONFIG_MODULES
@@ -3336,18 +3428,17 @@ replay:
 	if (err < 0)
 		return err;
 
-	if (tb[IFLA_IFNAME])
-		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
-	else
-		ifname[0] = '\0';
-
 	ifm = nlmsg_data(nlh);
-	if (ifm->ifi_index > 0)
+	if (ifm->ifi_index > 0) {
+		link_specified = true;
 		dev = __dev_get_by_index(net, ifm->ifi_index);
-	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
-		dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname);
-	else
+	} else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) {
+		link_specified = true;
+		dev = rtnl_dev_get(net, tb);
+	} else {
+		link_specified = false;
 		dev = NULL;
+	}
 
 	master_dev = NULL;
 	m_ops = NULL;
@@ -3384,12 +3475,12 @@ replay:
 			return -EINVAL;
 
 		if (ops->maxtype && linkinfo[IFLA_INFO_DATA]) {
-			err = nla_parse_nested_deprecated(attr, ops->maxtype,
+			err = nla_parse_nested_deprecated(tbs->attr, ops->maxtype,
 							  linkinfo[IFLA_INFO_DATA],
 							  ops->policy, extack);
 			if (err < 0)
 				return err;
-			data = attr;
+			data = tbs->attr;
 		}
 		if (ops->validate) {
 			err = ops->validate(tb, data, extack);
@@ -3405,14 +3496,14 @@ replay:
 
 		if (m_ops->slave_maxtype &&
 		    linkinfo[IFLA_INFO_SLAVE_DATA]) {
-			err = nla_parse_nested_deprecated(slave_attr,
+			err = nla_parse_nested_deprecated(tbs->slave_attr,
 							  m_ops->slave_maxtype,
 							  linkinfo[IFLA_INFO_SLAVE_DATA],
 							  m_ops->slave_policy,
 							  extack);
 			if (err < 0)
 				return err;
-			slave_data = slave_attr;
+			slave_data = tbs->slave_attr;
 		}
 	}
 
@@ -3446,11 +3537,16 @@ replay:
 			status |= DO_SETLINK_NOTIFY;
 		}
 
-		return do_setlink(skb, dev, ifm, extack, tb, ifname, status);
+		return do_setlink(skb, dev, ifm, extack, tb, status);
 	}
 
 	if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
-		if (ifm->ifi_index == 0 && tb[IFLA_GROUP])
+		/* No dev found and NLM_F_CREATE not set. Requested dev does not exist,
+		 * or it's for a group
+		*/
+		if (link_specified)
+			return -ENODEV;
+		if (tb[IFLA_GROUP])
 			return rtnl_group_changelink(skb, net,
 						nla_get_u32(tb[IFLA_GROUP]),
 						ifm, extack, tb);
@@ -3475,94 +3571,21 @@ replay:
 		return -EOPNOTSUPP;
 	}
 
-	if (!ops->alloc && !ops->setup)
-		return -EOPNOTSUPP;
-
-	if (!ifname[0]) {
-		snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
-		name_assign_type = NET_NAME_ENUM;
-	}
-
-	dest_net = rtnl_link_get_net_capable(skb, net, tb, CAP_NET_ADMIN);
-	if (IS_ERR(dest_net))
-		return PTR_ERR(dest_net);
-
-	if (tb[IFLA_LINK_NETNSID]) {
-		int id = nla_get_s32(tb[IFLA_LINK_NETNSID]);
-
-		link_net = get_net_ns_by_id(dest_net, id);
-		if (!link_net) {
-			NL_SET_ERR_MSG(extack, "Unknown network namespace id");
-			err =  -EINVAL;
-			goto out;
-		}
-		err = -EPERM;
-		if (!netlink_ns_capable(skb, link_net->user_ns, CAP_NET_ADMIN))
-			goto out;
-	} else {
-		link_net = NULL;
-	}
-
-	dev = rtnl_create_link(link_net ? : dest_net, ifname,
-			       name_assign_type, ops, tb, extack);
-	if (IS_ERR(dev)) {
-		err = PTR_ERR(dev);
-		goto out;
-	}
-
-	dev->ifindex = ifm->ifi_index;
-
-	if (ops->newlink)
-		err = ops->newlink(link_net ? : net, dev, tb, data, extack);
-	else
-		err = register_netdevice(dev);
-	if (err < 0) {
-		free_netdev(dev);
-		goto out;
-	}
-
-	err = rtnl_configure_link(dev, ifm);
-	if (err < 0)
-		goto out_unregister;
-	if (link_net) {
-		err = dev_change_net_namespace(dev, dest_net, ifname);
-		if (err < 0)
-			goto out_unregister;
-	}
-	if (tb[IFLA_MASTER]) {
-		err = do_set_master(dev, nla_get_u32(tb[IFLA_MASTER]), extack);
-		if (err)
-			goto out_unregister;
-	}
-out:
-	if (link_net)
-		put_net(link_net);
-	put_net(dest_net);
-	return err;
-out_unregister:
-	if (ops->newlink) {
-		LIST_HEAD(list_kill);
-
-		ops->dellink(dev, &list_kill);
-		unregister_netdevice_many(&list_kill);
-	} else {
-		unregister_netdevice(dev);
-	}
-	goto out;
+	return rtnl_newlink_create(skb, ifm, ops, tb, data, extack);
 }
 
 static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 			struct netlink_ext_ack *extack)
 {
-	struct nlattr **attr;
+	struct rtnl_newlink_tbs *tbs;
 	int ret;
 
-	attr = kmalloc_array(RTNL_MAX_TYPE + 1, sizeof(*attr), GFP_KERNEL);
-	if (!attr)
+	tbs = kmalloc(sizeof(*tbs), GFP_KERNEL);
+	if (!tbs)
 		return -ENOMEM;
 
-	ret = __rtnl_newlink(skb, nlh, attr, extack);
-	kfree(attr);
+	ret = __rtnl_newlink(skb, nlh, tbs, extack);
+	kfree(tbs);
 	return ret;
 }
 
@@ -3650,8 +3673,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(tgt_net, ifm->ifi_index);
 	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
-		dev = rtnl_dev_get(tgt_net, tb[IFLA_IFNAME],
-				   tb[IFLA_ALT_IFNAME], NULL);
+		dev = rtnl_dev_get(tgt_net, tb);
 	else
 		goto out;
 
@@ -3746,8 +3768,7 @@ static int rtnl_linkprop(int cmd, struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (ifm->ifi_index > 0)
 		dev = __dev_get_by_index(net, ifm->ifi_index);
 	else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
-		dev = rtnl_dev_get(net, tb[IFLA_IFNAME],
-				   tb[IFLA_ALT_IFNAME], NULL);
+		dev = rtnl_dev_get(net, tb);
 	else
 		return -EINVAL;
 
@@ -4165,22 +4186,36 @@ int ndo_dflt_fdb_del(struct ndmsg *ndm,
 }
 EXPORT_SYMBOL(ndo_dflt_fdb_del);
 
+static const struct nla_policy fdb_del_bulk_policy[NDA_MAX + 1] = {
+	[NDA_VLAN]	= { .type = NLA_U16 },
+	[NDA_IFINDEX]	= NLA_POLICY_MIN(NLA_S32, 1),
+	[NDA_NDM_STATE_MASK]	= { .type = NLA_U16  },
+	[NDA_NDM_FLAGS_MASK]	= { .type = NLA_U8 },
+};
+
 static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 			struct netlink_ext_ack *extack)
 {
+	bool del_bulk = !!(nlh->nlmsg_flags & NLM_F_BULK);
 	struct net *net = sock_net(skb->sk);
+	const struct net_device_ops *ops;
 	struct ndmsg *ndm;
 	struct nlattr *tb[NDA_MAX+1];
 	struct net_device *dev;
-	__u8 *addr;
+	__u8 *addr = NULL;
 	int err;
 	u16 vid;
 
 	if (!netlink_capable(skb, CAP_NET_ADMIN))
 		return -EPERM;
 
-	err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX, NULL,
-				     extack);
+	if (!del_bulk) {
+		err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
+					     NULL, extack);
+	} else {
+		err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX,
+				  fdb_del_bulk_policy, extack);
+	}
 	if (err < 0)
 		return err;
 
@@ -4196,9 +4231,12 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return -ENODEV;
 	}
 
-	if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) {
-		NL_SET_ERR_MSG(extack, "invalid address");
-		return -EINVAL;
+	if (!del_bulk) {
+		if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) {
+			NL_SET_ERR_MSG(extack, "invalid address");
+			return -EINVAL;
+		}
+		addr = nla_data(tb[NDA_LLADDR]);
 	}
 
 	if (dev->type != ARPHRD_ETHER) {
@@ -4206,8 +4244,6 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return -EINVAL;
 	}
 
-	addr = nla_data(tb[NDA_LLADDR]);
-
 	err = fdb_vid_parse(tb[NDA_VLAN], &vid, extack);
 	if (err)
 		return err;
@@ -4218,10 +4254,16 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if ((!ndm->ndm_flags || ndm->ndm_flags & NTF_MASTER) &&
 	    netif_is_bridge_port(dev)) {
 		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
-		const struct net_device_ops *ops = br_dev->netdev_ops;
 
-		if (ops->ndo_fdb_del)
-			err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid);
+		ops = br_dev->netdev_ops;
+		if (!del_bulk) {
+			if (ops->ndo_fdb_del)
+				err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid);
+		} else {
+			if (ops->ndo_fdb_del_bulk)
+				err = ops->ndo_fdb_del_bulk(ndm, tb, dev, vid,
+							    extack);
+		}
 
 		if (err)
 			goto out;
@@ -4231,15 +4273,24 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	/* Embedded bridge, macvlan, and any other device support */
 	if (ndm->ndm_flags & NTF_SELF) {
-		if (dev->netdev_ops->ndo_fdb_del)
-			err = dev->netdev_ops->ndo_fdb_del(ndm, tb, dev, addr,
-							   vid);
-		else
-			err = ndo_dflt_fdb_del(ndm, tb, dev, addr, vid);
+		ops = dev->netdev_ops;
+		if (!del_bulk) {
+			if (ops->ndo_fdb_del)
+				err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid);
+			else
+				err = ndo_dflt_fdb_del(ndm, tb, dev, addr, vid);
+		} else {
+			/* in case err was cleared by NTF_MASTER call */
+			err = -EOPNOTSUPP;
+			if (ops->ndo_fdb_del_bulk)
+				err = ops->ndo_fdb_del_bulk(ndm, tb, dev, vid,
+							    extack);
+		}
 
 		if (!err) {
-			rtnl_fdb_notify(dev, addr, vid, RTM_DELNEIGH,
-					ndm->ndm_state);
+			if (!del_bulk)
+				rtnl_fdb_notify(dev, addr, vid, RTM_DELNEIGH,
+						ndm->ndm_state);
 			ndm->ndm_flags &= ~NTF_SELF;
 		}
 	}
@@ -5275,6 +5326,8 @@ static int rtnl_offload_xstats_fill(struct sk_buff *skb, struct net_device *dev,
 		*prividx = attr_id_l3_stats;
 
 		size_l3 = rtnl_offload_xstats_get_size_stats(dev, t_l3);
+		if (!size_l3)
+			goto skip_l3_stats;
 		attr = nla_reserve_64bit(skb, attr_id_l3_stats, size_l3,
 					 IFLA_OFFLOAD_XSTATS_UNSPEC);
 		if (!attr)
@@ -5286,6 +5339,7 @@ static int rtnl_offload_xstats_fill(struct sk_buff *skb, struct net_device *dev,
 			return err;
 
 		have_data = true;
+skip_l3_stats:
 		*prividx = 0;
 	}
 
@@ -5926,11 +5980,11 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 {
 	struct net *net = sock_net(skb->sk);
 	struct rtnl_link *link;
+	enum rtnl_kinds kind;
 	struct module *owner;
 	int err = -EOPNOTSUPP;
 	rtnl_doit_func doit;
 	unsigned int flags;
-	int kind;
 	int family;
 	int type;
 
@@ -5945,13 +5999,13 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return 0;
 
 	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
-	kind = type&3;
+	kind = rtnl_msgtype_kind(type);
 
-	if (kind != 2 && !netlink_net_capable(skb, CAP_NET_ADMIN))
+	if (kind != RTNL_KIND_GET && !netlink_net_capable(skb, CAP_NET_ADMIN))
 		return -EPERM;
 
 	rcu_read_lock();
-	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
+	if (kind == RTNL_KIND_GET && (nlh->nlmsg_flags & NLM_F_DUMP)) {
 		struct sock *rtnl;
 		rtnl_dumpit_func dumpit;
 		u32 min_dump_alloc = 0;
@@ -6007,6 +6061,12 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 	}
 
 	flags = link->flags;
+	if (kind == RTNL_KIND_DEL && (nlh->nlmsg_flags & NLM_F_BULK) &&
+	    !(flags & RTNL_FLAG_BULK_DEL_SUPPORTED)) {
+		NL_SET_ERR_MSG(extack, "Bulk delete is not supported");
+		goto err_unlock;
+	}
+
 	if (flags & RTNL_FLAG_DOIT_UNLOCKED) {
 		doit = link->doit;
 		rcu_read_unlock();
@@ -6135,7 +6195,8 @@ void __init rtnetlink_init(void)
 	rtnl_register(PF_UNSPEC, RTM_DELLINKPROP, rtnl_dellinkprop, NULL, 0);
 
 	rtnl_register(PF_BRIDGE, RTM_NEWNEIGH, rtnl_fdb_add, NULL, 0);
-	rtnl_register(PF_BRIDGE, RTM_DELNEIGH, rtnl_fdb_del, NULL, 0);
+	rtnl_register(PF_BRIDGE, RTM_DELNEIGH, rtnl_fdb_del, NULL,
+		      RTNL_FLAG_BULK_DEL_SUPPORTED);
 	rtnl_register(PF_BRIDGE, RTM_GETNEIGH, rtnl_fdb_get, rtnl_fdb_dump, 0);
 
 	rtnl_register(PF_BRIDGE, RTM_GETLINK, NULL, rtnl_bridge_getlink, 0);