mptcp: factor out __mptcp_close() without socket lock

Factor out __mptcp_close() from mptcp_close(). The caller of __mptcp_close() should hold the socket lock, and cancel mptcp work when __mptcp_close() returns true. This function will be used in the next commit. Fixes: f296234 ("mptcp: Add handling of incoming MP_JOIN requests") Fixes: 6aeed90 ("mptcp: fix race on unaccepted mptcp sockets") Cc: [email protected] Reviewed-by: Jiang Biao <[email protected]> Reviewed-by: Mengen Sun <[email protected]> Acked-by: Paolo Abeni <[email protected]> Signed-off-by: Menglong Dong <[email protected]> Signed-off-by: Mat Martineau <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]>
josf · Sep 29, 2022 · 26d3e21 · 26d3e21
1 parent 3e1308a
commit 26d3e21
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Showing 2 changed files with 13 additions and 2 deletions.
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
@@ -2802,13 +2802,12 @@ static void __mptcp_destroy_sock(struct sock *sk)
 	sock_put(sk);
 }
 
-static void mptcp_close(struct sock *sk, long timeout)
+bool __mptcp_close(struct sock *sk, long timeout)
 {
 	struct mptcp_subflow_context *subflow;
 	struct mptcp_sock *msk = mptcp_sk(sk);
 	bool do_cancel_work = false;
 
-	lock_sock(sk);
 	sk->sk_shutdown = SHUTDOWN_MASK;
 
 	if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) {
@@ -2850,6 +2849,17 @@ static void mptcp_close(struct sock *sk, long timeout)
 	} else {
 		mptcp_reset_timeout(msk, 0);
 	}
+
+	return do_cancel_work;
+}
+
+static void mptcp_close(struct sock *sk, long timeout)
+{
+	bool do_cancel_work;
+
+	lock_sock(sk);
+
+	do_cancel_work = __mptcp_close(sk, timeout);
 	release_sock(sk);
 	if (do_cancel_work)
 		mptcp_cancel_work(sk);

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
@@ -612,6 +612,7 @@ void mptcp_subflow_reset(struct sock *ssk);
 void mptcp_subflow_queue_clean(struct sock *ssk);
 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk);
+bool __mptcp_close(struct sock *sk, long timeout);
 
 bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
 			   const struct mptcp_addr_info *b, bool use_port);