Merge branch 'mptcp-fix-subflow-s-local_id-remote_id-issues'

Geliang Tang says:

====================
mptcp: fix subflow's local_id/remote_id issues

v2:
 - add Fixes tags;
 - simply with 'return addresses_equal';
 - use 'reversed Xmas tree' way.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/mptcp/pm_netlink.c

@@ -66,6 +66,16 @@ static bool addresses_equal(const struct mptcp_addr_info *a,
 	return a->port == b->port;
 }
 
+static bool address_zero(const struct mptcp_addr_info *addr)
+{
+	struct mptcp_addr_info zero;
+
+	memset(&zero, 0, sizeof(zero));
+	zero.family = addr->family;
+
+	return addresses_equal(addr, &zero, false);
+}
+
 static void local_address(const struct sock_common *skc,
 			  struct mptcp_addr_info *addr)
 {
@@ -171,9 +181,9 @@ static void check_work_pending(struct mptcp_sock *msk)
 
 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 {
+	struct mptcp_addr_info remote = { 0 };
 	struct sock *sk = (struct sock *)msk;
 	struct mptcp_pm_addr_entry *local;
-	struct mptcp_addr_info remote;
 	struct pm_nl_pernet *pernet;
 
 	pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
@@ -323,10 +333,13 @@ int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
 	 * addr
 	 */
 	local_address((struct sock_common *)msk, &msk_local);
-	local_address((struct sock_common *)msk, &skc_local);
+	local_address((struct sock_common *)skc, &skc_local);
 	if (addresses_equal(&msk_local, &skc_local, false))
 		return 0;
 
+	if (address_zero(&skc_local))
+		return 0;
+
 	pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
 
 	rcu_read_lock();

net/mptcp/subflow.c

@@ -1063,6 +1063,7 @@ int __mptcp_subflow_connect(struct sock *sk, int ifindex,
 	struct mptcp_sock *msk = mptcp_sk(sk);
 	struct mptcp_subflow_context *subflow;
 	struct sockaddr_storage addr;
+	int remote_id = remote->id;
 	int local_id = loc->id;
 	struct socket *sf;
 	struct sock *ssk;
@@ -1107,10 +1108,11 @@ int __mptcp_subflow_connect(struct sock *sk, int ifindex,
 		goto failed;
 
 	mptcp_crypto_key_sha(subflow->remote_key, &remote_token, NULL);
-	pr_debug("msk=%p remote_token=%u local_id=%d", msk, remote_token,
-		 local_id);
+	pr_debug("msk=%p remote_token=%u local_id=%d remote_id=%d", msk,
+		 remote_token, local_id, remote_id);
 	subflow->remote_token = remote_token;
 	subflow->local_id = local_id;
+	subflow->remote_id = remote_id;
 	subflow->request_join = 1;
 	subflow->request_bkup = 1;
 	mptcp_info2sockaddr(remote, &addr);
@@ -1347,6 +1349,7 @@ static void subflow_ulp_clone(const struct request_sock *req,
 		new_ctx->fully_established = 1;
 		new_ctx->backup = subflow_req->backup;
 		new_ctx->local_id = subflow_req->local_id;
+		new_ctx->remote_id = subflow_req->remote_id;
 		new_ctx->token = subflow_req->token;
 		new_ctx->thmac = subflow_req->thmac;
 	}