1 files changed, 20 insertions, 4 deletions

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index d398f3810662..f8897a70c11d 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -150,9 +150,15 @@ static bool mptcp_try_coalesce(struct sock *sk, struct sk_buff *to,
 		 MPTCP_SKB_CB(from)->map_seq, MPTCP_SKB_CB(to)->map_seq,
 		 to->len, MPTCP_SKB_CB(from)->end_seq);
 	MPTCP_SKB_CB(to)->end_seq = MPTCP_SKB_CB(from)->end_seq;
-	kfree_skb_partial(from, fragstolen);
+
+	/* note the fwd memory can reach a negative value after accounting
+	 * for the delta, but the later skb free will restore a non
+	 * negative one
+	 */
 	atomic_add(delta, &sk->sk_rmem_alloc);
 	mptcp_rmem_charge(sk, delta);
+	kfree_skb_partial(from, fragstolen);
+
 	return true;
 }
 
@@ -2656,7 +2662,7 @@ static void __mptcp_clear_xmit(struct sock *sk)
 		dfrag_clear(sk, dfrag);
 }
 
-static void mptcp_cancel_work(struct sock *sk)
+void mptcp_cancel_work(struct sock *sk)
 {
 	struct mptcp_sock *msk = mptcp_sk(sk);
 
@@ -2796,13 +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)) {
@@ -2844,6 +2849,17 @@ cleanup:
 	} 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);