4 files changed, 27 insertions, 14 deletions

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index b42c429cebbe..3364cb9c67e0 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -1661,7 +1661,7 @@ EXPORT_SYMBOL_GPL(fib_nexthop_info);
 
 #if IS_ENABLED(CONFIG_IP_ROUTE_MULTIPATH) || IS_ENABLED(CONFIG_IPV6)
 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nhc,
-		    int nh_weight, u8 rt_family)
+		    int nh_weight, u8 rt_family, u32 nh_tclassid)
 {
 	const struct net_device *dev = nhc->nhc_dev;
 	struct rtnexthop *rtnh;
@@ -1679,6 +1679,9 @@ int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nhc,
 
 	rtnh->rtnh_flags = flags;
 
+	if (nh_tclassid && nla_put_u32(skb, RTA_FLOW, nh_tclassid))
+		goto nla_put_failure;
+
 	/* length of rtnetlink header + attributes */
 	rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh;
 
@@ -1706,14 +1709,13 @@ static int fib_add_multipath(struct sk_buff *skb, struct fib_info *fi)
 	}
 
 	for_nexthops(fi) {
-		if (fib_add_nexthop(skb, &nh->nh_common, nh->fib_nh_weight,
-				    AF_INET) < 0)
-			goto nla_put_failure;
+		u32 nh_tclassid = 0;
 #ifdef CONFIG_IP_ROUTE_CLASSID
-		if (nh->nh_tclassid &&
-		    nla_put_u32(skb, RTA_FLOW, nh->nh_tclassid))
-			goto nla_put_failure;
+		nh_tclassid = nh->nh_tclassid;
 #endif
+		if (fib_add_nexthop(skb, &nh->nh_common, nh->fib_nh_weight,
+				    AF_INET, nh_tclassid) < 0)
+			goto nla_put_failure;
 	} endfor_nexthops(fi);
 
 mp_end:
diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index 75ca4b6e484f..9e8100728d46 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -1982,6 +1982,8 @@ static int replace_nexthop_grp(struct net *net, struct nexthop *old,
 	rcu_assign_pointer(old->nh_grp, newg);
 
 	if (newg->resilient) {
+		/* Make sure concurrent readers are not using 'oldg' anymore. */
+		synchronize_net();
 		rcu_assign_pointer(oldg->res_table, tmp_table);
 		rcu_assign_pointer(oldg->spare->res_table, tmp_table);
 	}
@@ -3565,6 +3567,7 @@ static struct notifier_block nh_netdev_notifier = {
 };
 
 static int nexthops_dump(struct net *net, struct notifier_block *nb,
+			 enum nexthop_event_type event_type,
 			 struct netlink_ext_ack *extack)
 {
 	struct rb_root *root = &net->nexthop.rb_root;
@@ -3575,8 +3578,7 @@ static int nexthops_dump(struct net *net, struct notifier_block *nb,
 		struct nexthop *nh;
 
 		nh = rb_entry(node, struct nexthop, rb_node);
-		err = call_nexthop_notifier(nb, net, NEXTHOP_EVENT_REPLACE, nh,
-					    extack);
+		err = call_nexthop_notifier(nb, net, event_type, nh, extack);
 		if (err)
 			break;
 	}
@@ -3590,7 +3592,7 @@ int register_nexthop_notifier(struct net *net, struct notifier_block *nb,
 	int err;
 
 	rtnl_lock();
-	err = nexthops_dump(net, nb, extack);
+	err = nexthops_dump(net, nb, NEXTHOP_EVENT_REPLACE, extack);
 	if (err)
 		goto unlock;
 	err = blocking_notifier_chain_register(&net->nexthop.notifier_chain,
@@ -3603,8 +3605,17 @@ EXPORT_SYMBOL(register_nexthop_notifier);
 
 int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb)
 {
-	return blocking_notifier_chain_unregister(&net->nexthop.notifier_chain,
-						  nb);
+	int err;
+
+	rtnl_lock();
+	err = blocking_notifier_chain_unregister(&net->nexthop.notifier_chain,
+						 nb);
+	if (err)
+		goto unlock;
+	nexthops_dump(net, nb, NEXTHOP_EVENT_DEL, NULL);
+unlock:
+	rtnl_unlock();
+	return err;
 }
 EXPORT_SYMBOL(unregister_nexthop_notifier);
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 3f7bd7ae7d7a..141e85e6422b 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1346,7 +1346,7 @@ static u8 tcp_sacktag_one(struct sock *sk,
 	if (dup_sack && (sacked & TCPCB_RETRANS)) {
 		if (tp->undo_marker && tp->undo_retrans > 0 &&
 		    after(end_seq, tp->undo_marker))
-			tp->undo_retrans--;
+			tp->undo_retrans = max_t(int, 0, tp->undo_retrans - pcount);
 		if ((sacked & TCPCB_SACKED_ACKED) &&
 		    before(start_seq, state->reord))
 				state->reord = start_seq;
diff --git a/net/ipv4/udp_tunnel_nic.c b/net/ipv4/udp_tunnel_nic.c
index 0d122edc368d..b91003538d87 100644
--- a/net/ipv4/udp_tunnel_nic.c
+++ b/net/ipv4/udp_tunnel_nic.c
@@ -935,7 +935,7 @@ static int __init udp_tunnel_nic_init_module(void)
 {
 	int err;
 
-	udp_tunnel_nic_workqueue = alloc_workqueue("udp_tunnel_nic", 0, 0);
+	udp_tunnel_nic_workqueue = alloc_ordered_workqueue("udp_tunnel_nic", 0);
 	if (!udp_tunnel_nic_workqueue)
 		return -ENOMEM;