inet: move inet->recverr_rfc4884 to inet->inet_flags

IP_RECVERR_RFC4884 socket option can now be set/read
without locking the socket.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/inet_sock.h

@@ -238,7 +238,6 @@ struct inet_sock {
 				mc_all:1,
 				nodefrag:1;
 	__u8			bind_address_no_port:1,
-				recverr_rfc4884:1,
 				defer_connect:1; /* Indicates that fastopen_connect is set
 						  * and cookie exists so we defer connect
 						  * until first data frame is written
@@ -271,6 +270,7 @@ enum {
 	INET_FLAGS_RECVFRAGSIZE	= 8,
 
 	INET_FLAGS_RECVERR	= 9,
+	INET_FLAGS_RECVERR_RFC4884 = 10,
 };
 
 /* cmsg flags for inet */

net/ipv4/inet_diag.c

@@ -191,7 +191,7 @@ int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
 	inet_sockopt.mc_all	= inet->mc_all;
 	inet_sockopt.nodefrag	= inet->nodefrag;
 	inet_sockopt.bind_address_no_port = inet->bind_address_no_port;
-	inet_sockopt.recverr_rfc4884 = inet->recverr_rfc4884;
+	inet_sockopt.recverr_rfc4884 = inet_test_bit(RECVERR_RFC4884, sk);
 	inet_sockopt.defer_connect = inet->defer_connect;
 	if (nla_put(skb, INET_DIAG_SOCKOPT, sizeof(inet_sockopt),
 		    &inet_sockopt))

net/ipv4/ip_sockglue.c

@@ -433,7 +433,7 @@ void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 	serr->port = port;
 
 	if (skb_pull(skb, payload - skb->data)) {
-		if (inet_sk(sk)->recverr_rfc4884)
+		if (inet_test_bit(RECVERR_RFC4884, sk))
 			ipv4_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
 
 		skb_reset_transport_header(skb);
@@ -980,6 +980,11 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname,
 		if (!val)
 			skb_queue_purge(&sk->sk_error_queue);
 		return 0;
+	case IP_RECVERR_RFC4884:
+		if (val < 0 || val > 1)
+			return -EINVAL;
+		inet_assign_bit(RECVERR_RFC4884, sk, val);
+		return 0;
 	}
 
 	err = 0;
@@ -1066,11 +1071,6 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname,
 			goto e_inval;
 		inet->pmtudisc = val;
 		break;
-	case IP_RECVERR_RFC4884:
-		if (val < 0 || val > 1)
-			goto e_inval;
-		inet->recverr_rfc4884 = !!val;
-		break;
 	case IP_MULTICAST_TTL:
 		if (sk->sk_type == SOCK_STREAM)
 			goto e_inval;
@@ -1575,6 +1575,9 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname,
 	case IP_RECVERR:
 		val = inet_test_bit(RECVERR, sk);
 		goto copyval;
+	case IP_RECVERR_RFC4884:
+		val = inet_test_bit(RECVERR_RFC4884, sk);
+		goto copyval;
 	}
 
 	if (needs_rtnl)
@@ -1649,9 +1652,6 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname,
 		}
 		break;
 	}
-	case IP_RECVERR_RFC4884:
-		val = inet->recverr_rfc4884;
-		break;
 	case IP_MULTICAST_TTL:
 		val = inet->mc_ttl;
 		break;