Bluetooth: hci_core: Fix LE quote calculation

Function hci_sched_le needs to update the respective counter variable
inplace other the likes of hci_quote_sent would attempt to use the
possible outdated value of conn->{le_cnt,acl_cnt}.

Link: bluez/bluez#915
Fixes: 73d80de ("Bluetooth: prioritizing data over HCI")
Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: Vudentz

net/bluetooth/hci_core.c

@@ -3664,19 +3664,19 @@ static void hci_sched_le(struct hci_dev *hdev)
 {
 	struct hci_chan *chan;
 	struct sk_buff *skb;
-	int quote, cnt, tmp;
+	int quote, *cnt, tmp;
 
 	BT_DBG("%s", hdev->name);
 
 	if (!hci_conn_num(hdev, LE_LINK))
 		return;
 
-	cnt = hdev->le_pkts ? hdev->le_cnt : hdev->acl_cnt;
+	cnt = hdev->le_pkts ? &hdev->le_cnt : &hdev->acl_cnt;
 
-	__check_timeout(hdev, cnt, LE_LINK);
+	__check_timeout(hdev, *cnt, LE_LINK);
 
-	tmp = cnt;
-	while (cnt && (chan = hci_chan_sent(hdev, LE_LINK, &quote))) {
+	tmp = *cnt;
+	while (*cnt && (chan = hci_chan_sent(hdev, LE_LINK, &quote))) {
 		u32 priority = (skb_peek(&chan->data_q))->priority;
 		while (quote-- && (skb = skb_peek(&chan->data_q))) {
 			BT_DBG("chan %p skb %p len %d priority %u", chan, skb,
@@ -3691,7 +3691,7 @@ static void hci_sched_le(struct hci_dev *hdev)
 			hci_send_frame(hdev, skb);
 			hdev->le_last_tx = jiffies;
 
-			cnt--;
+			(*cnt)--;
 			chan->sent++;
 			chan->conn->sent++;
 
@@ -3701,12 +3701,7 @@ static void hci_sched_le(struct hci_dev *hdev)
 		}
 	}
 
-	if (hdev->le_pkts)
-		hdev->le_cnt = cnt;
-	else
-		hdev->acl_cnt = cnt;
-
-	if (cnt != tmp)
+	if (*cnt != tmp)
 		hci_prio_recalculate(hdev, LE_LINK);
 }