Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 1fbe2f8..70f92aa 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * INET		An implementation of the TCP/IP protocol suite for the LINUX
  *		operating system.  INET is implemented using the  BSD Socket
@@ -58,11 +59,6 @@
  *					Some other random speedups.
  *		Cyrus Durgin	:	Cleaned up file for kmod hacks.
  *		Andi Kleen	:	Fix inet_stream_connect TCP race.
- *
- *		This program is free software; you can redistribute it and/or
- *		modify it under the terms of the GNU General Public License
- *		as published by the Free Software Foundation; either version
- *		2 of the License, or (at your option) any later version.
  */
 
 #define pr_fmt(fmt) "IPv4: " fmt
@@ -136,6 +132,10 @@
 	struct inet_sock *inet = inet_sk(sk);
 
 	__skb_queue_purge(&sk->sk_receive_queue);
+	if (sk->sk_rx_skb_cache) {
+		__kfree_skb(sk->sk_rx_skb_cache);
+		sk->sk_rx_skb_cache = NULL;
+	}
 	__skb_queue_purge(&sk->sk_error_queue);
 
 	sk_mem_reclaim(sk);
@@ -156,7 +156,7 @@
 	WARN_ON(sk->sk_forward_alloc);
 
 	kfree(rcu_dereference_protected(inet->inet_opt, 1));
-	dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
+	dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
 	dst_release(sk->sk_rx_dst);
 	sk_refcnt_debug_dec(sk);
 }
@@ -208,6 +208,7 @@
 	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
 		goto out;
 
+	sk->sk_max_ack_backlog = backlog;
 	/* Really, if the socket is already in listen state
 	 * we can only allow the backlog to be adjusted.
 	 */
@@ -231,7 +232,6 @@
 			goto out;
 		tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_LISTEN_CB, 0, NULL);
 	}
-	sk->sk_max_ack_backlog = backlog;
 	err = 0;
 
 out:
@@ -424,8 +424,8 @@
 		if (sock_flag(sk, SOCK_LINGER) &&
 		    !(current->flags & PF_EXITING))
 			timeout = sk->sk_lingertime;
-		sock->sk = NULL;
 		sk->sk_prot->close(sk, timeout);
+		sock->sk = NULL;
 	}
 	return 0;
 }
@@ -784,10 +784,8 @@
 }
 EXPORT_SYMBOL(inet_getname);
 
-int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
+int inet_send_prepare(struct sock *sk)
 {
-	struct sock *sk = sock->sk;
-
 	sock_rps_record_flow(sk);
 
 	/* We may need to bind the socket. */
@@ -795,7 +793,19 @@
 	    inet_autobind(sk))
 		return -EAGAIN;
 
-	return sk->sk_prot->sendmsg(sk, msg, size);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(inet_send_prepare);
+
+int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
+{
+	struct sock *sk = sock->sk;
+
+	if (unlikely(inet_send_prepare(sk)))
+		return -EAGAIN;
+
+	return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udp_sendmsg,
+			       sk, msg, size);
 }
 EXPORT_SYMBOL(inet_sendmsg);
 
@@ -804,11 +814,7 @@
 {
 	struct sock *sk = sock->sk;
 
-	sock_rps_record_flow(sk);
-
-	/* We may need to bind the socket. */
-	if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
-	    inet_autobind(sk))
+	if (unlikely(inet_send_prepare(sk)))
 		return -EAGAIN;
 
 	if (sk->sk_prot->sendpage)
@@ -817,6 +823,8 @@
 }
 EXPORT_SYMBOL(inet_sendpage);
 
+INDIRECT_CALLABLE_DECLARE(int udp_recvmsg(struct sock *, struct msghdr *,
+					  size_t, int, int, int *));
 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 		 int flags)
 {
@@ -827,8 +835,9 @@
 	if (likely(!(flags & MSG_ERRQUEUE)))
 		sock_rps_record_flow(sk);
 
-	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
-				   flags & ~MSG_DONTWAIT, &addr_len);
+	err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
+			      sk, msg, size, flags & MSG_DONTWAIT,
+			      flags & ~MSG_DONTWAIT, &addr_len);
 	if (err >= 0)
 		msg->msg_namelen = addr_len;
 	return err;
@@ -911,12 +920,6 @@
 	struct rtentry rt;
 
 	switch (cmd) {
-	case SIOCGSTAMP:
-		err = sock_get_timestamp(sk, (struct timeval __user *)arg);
-		break;
-	case SIOCGSTAMPNS:
-		err = sock_get_timestampns(sk, (struct timespec __user *)arg);
-		break;
 	case SIOCADDRT:
 	case SIOCDELRT:
 		if (copy_from_user(&rt, p, sizeof(struct rtentry)))
@@ -988,6 +991,7 @@
 	.getname	   = inet_getname,
 	.poll		   = tcp_poll,
 	.ioctl		   = inet_ioctl,
+	.gettstamp	   = sock_gettstamp,
 	.listen		   = inet_listen,
 	.shutdown	   = inet_shutdown,
 	.setsockopt	   = sock_common_setsockopt,
@@ -1023,6 +1027,7 @@
 	.getname	   = inet_getname,
 	.poll		   = udp_poll,
 	.ioctl		   = inet_ioctl,
+	.gettstamp	   = sock_gettstamp,
 	.listen		   = sock_no_listen,
 	.shutdown	   = inet_shutdown,
 	.setsockopt	   = sock_common_setsockopt,
@@ -1055,6 +1060,7 @@
 	.getname	   = inet_getname,
 	.poll		   = datagram_poll,
 	.ioctl		   = inet_ioctl,
+	.gettstamp	   = sock_gettstamp,
 	.listen		   = sock_no_listen,
 	.shutdown	   = inet_shutdown,
 	.setsockopt	   = sock_common_setsockopt,
@@ -1385,6 +1391,19 @@
 }
 EXPORT_SYMBOL(inet_gso_segment);
 
+static struct sk_buff *ipip_gso_segment(struct sk_buff *skb,
+					netdev_features_t features)
+{
+	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
+		return ERR_PTR(-EINVAL);
+
+	return inet_gso_segment(skb, features);
+}
+
+INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp4_gro_receive(struct list_head *,
+							   struct sk_buff *));
+INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
+							   struct sk_buff *));
 struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
 {
 	const struct net_offload *ops;
@@ -1494,7 +1513,8 @@
 	skb_gro_pull(skb, sizeof(*iph));
 	skb_set_transport_header(skb, skb_gro_offset(skb));
 
-	pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
+	pp = indirect_call_gro_receive(tcp4_gro_receive, udp4_gro_receive,
+				       ops->callbacks.gro_receive, head, skb);
 
 out_unlock:
 	rcu_read_unlock();
@@ -1556,6 +1576,8 @@
 	return -EINVAL;
 }
 
+INDIRECT_CALLABLE_DECLARE(int tcp4_gro_complete(struct sk_buff *, int));
+INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
 int inet_gro_complete(struct sk_buff *skb, int nhoff)
 {
 	__be16 newlen = htons(skb->len - nhoff);
@@ -1581,7 +1603,9 @@
 	 * because any hdr with option will have been flushed in
 	 * inet_gro_receive().
 	 */
-	err = ops->callbacks.gro_complete(skb, nhoff + sizeof(*iph));
+	err = INDIRECT_CALL_2(ops->callbacks.gro_complete,
+			      tcp4_gro_complete, udp4_gro_complete,
+			      skb, nhoff + sizeof(*iph));
 
 out_unlock:
 	rcu_read_unlock();
@@ -1821,13 +1845,8 @@
 	return 0;
 }
 
-static __net_exit void inet_exit_net(struct net *net)
-{
-}
-
 static __net_initdata struct pernet_operations af_inet_ops = {
 	.init = inet_init_net,
-	.exit = inet_exit_net,
 };
 
 static int __init init_inet_pernet_ops(void)
@@ -1852,7 +1871,7 @@
 
 static const struct net_offload ipip_offload = {
 	.callbacks = {
-		.gso_segment	= inet_gso_segment,
+		.gso_segment	= ipip_gso_segment,
 		.gro_receive	= ipip_gro_receive,
 		.gro_complete	= ipip_gro_complete,
 	},
@@ -1964,6 +1983,8 @@
 	/* Add UDP-Lite (RFC 3828) */
 	udplite4_register();
 
+	raw_init();
+
 	ping_init();
 
 	/*