net: annotate lockless accesses to sk->sk_err_soft

This field can be read/written without lock synchronization.

tcp and dccp have been handled in different patches.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: edumazet

fs/dlm/lowcomms.c

@@ -601,7 +601,7 @@ static void lowcomms_error_report(struct sock *sk)
 				   "sk_err=%d/%d\n", dlm_our_nodeid(),
 				   con->nodeid, &inet->inet_daddr,
 				   ntohs(inet->inet_dport), sk->sk_err,
-				   sk->sk_err_soft);
+				   READ_ONCE(sk->sk_err_soft));
 		break;
 #if IS_ENABLED(CONFIG_IPV6)
 	case AF_INET6:
@@ -610,14 +610,15 @@ static void lowcomms_error_report(struct sock *sk)
 				   "dport %d, sk_err=%d/%d\n", dlm_our_nodeid(),
 				   con->nodeid, &sk->sk_v6_daddr,
 				   ntohs(inet->inet_dport), sk->sk_err,
-				   sk->sk_err_soft);
+				   READ_ONCE(sk->sk_err_soft));
 		break;
 #endif
 	default:
 		printk_ratelimited(KERN_ERR "dlm: node %d: socket error "
 				   "invalid socket family %d set, "
 				   "sk_err=%d/%d\n", dlm_our_nodeid(),
-				   sk->sk_family, sk->sk_err, sk->sk_err_soft);
+				   sk->sk_family, sk->sk_err,
+				   READ_ONCE(sk->sk_err_soft));
 		break;
 	}
 

net/atm/signaling.c

@@ -125,7 +125,7 @@ static int sigd_send(struct atm_vcc *vcc, struct sk_buff *skb)
 		break;
 	case as_addparty:
 	case as_dropparty:
-		sk->sk_err_soft = -msg->reply;
+		WRITE_ONCE(sk->sk_err_soft, -msg->reply);
 					/* < 0 failure, otherwise ep_ref */
 		clear_bit(ATM_VF_WAITING, &vcc->flags);
 		break;

net/ipv4/af_inet.c

@@ -1322,7 +1322,7 @@ int inet_sk_rebuild_header(struct sock *sk)
 		    sk->sk_state != TCP_SYN_SENT ||
 		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
 		    (err = inet_sk_reselect_saddr(sk)) != 0)
-			sk->sk_err_soft = -err;
+			WRITE_ONCE(sk->sk_err_soft, -err);
 	}
 
 	return err;

net/ipv6/af_inet6.c

@@ -845,7 +845,7 @@ int inet6_sk_rebuild_header(struct sock *sk)
 		dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 		if (IS_ERR(dst)) {
 			sk->sk_route_caps = 0;
-			sk->sk_err_soft = -PTR_ERR(dst);
+			WRITE_ONCE(sk->sk_err_soft, -PTR_ERR(dst));
 			return PTR_ERR(dst);
 		}
 

net/ipv6/inet6_connection_sock.c

@@ -120,7 +120,7 @@ int inet6_csk_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl_unused
 
 	dst = inet6_csk_route_socket(sk, &fl6);
 	if (IS_ERR(dst)) {
-		sk->sk_err_soft = -PTR_ERR(dst);
+		WRITE_ONCE(sk->sk_err_soft, -PTR_ERR(dst));
 		sk->sk_route_caps = 0;
 		kfree_skb(skb);
 		return PTR_ERR(dst);

net/sctp/input.c

@@ -585,7 +585,7 @@ static void sctp_v4_err_handle(struct sctp_transport *t, struct sk_buff *skb,
 		sk->sk_err = err;
 		sk_error_report(sk);
 	} else {  /* Only an error on timeout */
-		sk->sk_err_soft = err;
+		WRITE_ONCE(sk->sk_err_soft, err);
 	}
 }
 

net/sctp/ipv6.c

@@ -155,7 +155,7 @@ static void sctp_v6_err_handle(struct sctp_transport *t, struct sk_buff *skb,
 		sk->sk_err = err;
 		sk_error_report(sk);
 	} else {
-		sk->sk_err_soft = err;
+		WRITE_ONCE(sk->sk_err_soft, err);
 	}
 }