1 files changed, 51 insertions, 15 deletions

diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index 134e92382275..8c0f17c6863c 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -42,8 +42,8 @@ static int call_nexthop_notifiers(struct net *net,
 {
 	int err;
 
-	err = atomic_notifier_call_chain(&net->nexthop.notifier_chain,
-					 event_type, nh);
+	err = blocking_notifier_call_chain(&net->nexthop.notifier_chain,
+					   event_type, nh);
 	return notifier_to_errno(err);
 }
 
@@ -133,12 +133,9 @@ static struct nexthop *nexthop_alloc(void)
 
 static struct nh_group *nexthop_grp_alloc(u16 num_nh)
 {
-	size_t sz = offsetof(struct nexthop, nh_grp)
-		    + sizeof(struct nh_group)
-		    + sizeof(struct nh_grp_entry) * num_nh;
 	struct nh_group *nhg;
 
-	nhg = kzalloc(sz, GFP_KERNEL);
+	nhg = kzalloc(struct_size(nhg, nh_entries, num_nh), GFP_KERNEL);
 	if (nhg)
 		nhg->num_nh = num_nh;
 
@@ -279,7 +276,7 @@ static int nh_fill_node(struct sk_buff *skb, struct nexthop *nh,
 	case AF_INET:
 		fib_nh = &nhi->fib_nh;
 		if (fib_nh->fib_nh_gw_family &&
-		    nla_put_u32(skb, NHA_GATEWAY, fib_nh->fib_nh_gw4))
+		    nla_put_be32(skb, NHA_GATEWAY, fib_nh->fib_nh_gw4))
 			goto nla_put_failure;
 		break;
 
@@ -800,7 +797,7 @@ static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge,
 		return;
 	}
 
-	newg->has_v4 = nhg->has_v4;
+	newg->has_v4 = false;
 	newg->mpath = nhg->mpath;
 	newg->fdb_nh = nhg->fdb_nh;
 	newg->num_nh = nhg->num_nh;
@@ -809,12 +806,18 @@ static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge,
 	nhges = nhg->nh_entries;
 	new_nhges = newg->nh_entries;
 	for (i = 0, j = 0; i < nhg->num_nh; ++i) {
+		struct nh_info *nhi;
+
 		/* current nexthop getting removed */
 		if (nhg->nh_entries[i].nh == nh) {
 			newg->num_nh--;
 			continue;
 		}
 
+		nhi = rtnl_dereference(nhges[i].nh->nh_info);
+		if (nhi->family == AF_INET)
+			newg->has_v4 = true;
+
 		list_del(&nhges[i].nh_list);
 		new_nhges[j].nh_parent = nhges[i].nh_parent;
 		new_nhges[j].nh = nhges[i].nh;
@@ -867,8 +870,6 @@ static void __remove_nexthop_fib(struct net *net, struct nexthop *nh)
 	bool do_flush = false;
 	struct fib_info *fi;
 
-	call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh);
-
 	list_for_each_entry(fi, &nh->fi_list, nh_list) {
 		fi->fib_flags |= RTNH_F_DEAD;
 		do_flush = true;
@@ -906,6 +907,8 @@ static void __remove_nexthop(struct net *net, struct nexthop *nh,
 static void remove_nexthop(struct net *net, struct nexthop *nh,
 			   struct nl_info *nlinfo)
 {
+	call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh);
+
 	/* remove from the tree */
 	rb_erase(&nh->rb_node, &net->nexthop.rb_root);
 
@@ -961,6 +964,23 @@ static int replace_nexthop_grp(struct net *net, struct nexthop *old,
 	return 0;
 }
 
+static void nh_group_v4_update(struct nh_group *nhg)
+{
+	struct nh_grp_entry *nhges;
+	bool has_v4 = false;
+	int i;
+
+	nhges = nhg->nh_entries;
+	for (i = 0; i < nhg->num_nh; i++) {
+		struct nh_info *nhi;
+
+		nhi = rtnl_dereference(nhges[i].nh->nh_info);
+		if (nhi->family == AF_INET)
+			has_v4 = true;
+	}
+	nhg->has_v4 = has_v4;
+}
+
 static int replace_nexthop_single(struct net *net, struct nexthop *old,
 				  struct nexthop *new,
 				  struct netlink_ext_ack *extack)
@@ -984,6 +1004,21 @@ static int replace_nexthop_single(struct net *net, struct nexthop *old,
 	rcu_assign_pointer(old->nh_info, newi);
 	rcu_assign_pointer(new->nh_info, oldi);
 
+	/* When replacing an IPv4 nexthop with an IPv6 nexthop, potentially
+	 * update IPv4 indication in all the groups using the nexthop.
+	 */
+	if (oldi->family == AF_INET && newi->family == AF_INET6) {
+		struct nh_grp_entry *nhge;
+
+		list_for_each_entry(nhge, &old->grp_list, nh_list) {
+			struct nexthop *nhp = nhge->nh_parent;
+			struct nh_group *nhg;
+
+			nhg = rtnl_dereference(nhp->nh_grp);
+			nh_group_v4_update(nhg);
+		}
+	}
+
 	return 0;
 }
 
@@ -1101,7 +1136,7 @@ static int insert_nexthop(struct net *net, struct nexthop *new_nh,
 	while (1) {
 		struct nexthop *nh;
 
-		next = rtnl_dereference(*pp);
+		next = *pp;
 		if (!next)
 			break;
 
@@ -1924,14 +1959,15 @@ static struct notifier_block nh_netdev_notifier = {
 
 int register_nexthop_notifier(struct net *net, struct notifier_block *nb)
 {
-	return atomic_notifier_chain_register(&net->nexthop.notifier_chain, nb);
+	return blocking_notifier_chain_register(&net->nexthop.notifier_chain,
+						nb);
 }
 EXPORT_SYMBOL(register_nexthop_notifier);
 
 int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb)
 {
-	return atomic_notifier_chain_unregister(&net->nexthop.notifier_chain,
-						nb);
+	return blocking_notifier_chain_unregister(&net->nexthop.notifier_chain,
+						  nb);
 }
 EXPORT_SYMBOL(unregister_nexthop_notifier);
 
@@ -1951,7 +1987,7 @@ static int __net_init nexthop_net_init(struct net *net)
 	net->nexthop.devhash = kzalloc(sz, GFP_KERNEL);
 	if (!net->nexthop.devhash)
 		return -ENOMEM;
-	ATOMIC_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain);
+	BLOCKING_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain);
 
 	return 0;
 }