[PATCH v2 1/4] mptcp: fix ADD_ADDR and RM_ADDR maybe flush addr_signal each other

[Yonglong Li <liyonglong@chinatelecom.cn>]

ADD_ADDR share pm.addr_signal with RM_ADDR, so after RM_ADDR/ADD_ADDR
done we should not clean ADD_ADDR/RM_ADDR's addr_signal.

Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
---
 net/mptcp/pm.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 9d00fa6..74886a3 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -252,6 +252,7 @@ void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup)
 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 			      struct mptcp_addr_info *saddr, bool *echo, bool *port)
 {
+	u8 add_addr;
 	int ret = false;
 
 	spin_lock_bh(&msk->pm.lock);
@@ -267,7 +268,8 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 		goto out_unlock;
 
 	*saddr = msk->pm.local;
-	WRITE_ONCE(msk->pm.addr_signal, 0);
+	add_addr = msk->pm.addr_signal & BIT(MPTCP_RM_ADDR_SIGNAL);
+	WRITE_ONCE(msk->pm.addr_signal, add_addr);
 	ret = true;
 
 out_unlock:
@@ -278,6 +280,7 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 			     struct mptcp_rm_list *rm_list)
 {
+	u8 rm_addr;
 	int ret = false, len;
 
 	spin_lock_bh(&msk->pm.lock);
@@ -286,16 +289,17 @@ bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 	if (!mptcp_pm_should_rm_signal(msk))
 		goto out_unlock;
 
+	rm_addr = msk->pm.addr_signal & ~BIT(MPTCP_RM_ADDR_SIGNAL);
 	len = mptcp_rm_addr_len(&msk->pm.rm_list_tx);
 	if (len < 0) {
-		WRITE_ONCE(msk->pm.addr_signal, 0);
+		WRITE_ONCE(msk->pm.addr_signal, rm_addr);
 		goto out_unlock;
 	}
 	if (remaining < len)
 		goto out_unlock;
 
 	*rm_list = msk->pm.rm_list_tx;
-	WRITE_ONCE(msk->pm.addr_signal, 0);
+	WRITE_ONCE(msk->pm.addr_signal, rm_addr);
 	ret = true;
 
 out_unlock:
-- 
1.8.3.1