qcacld-3.0: Fix wrong return value of QCMBR command

qcacld-2.0 to qcacld-3.0 propagation

If wlan_hdd_qcmbr_command returns -EAGAIN and
pqcmbr_data->copy_to_user is set to 1, -EAGAIN will be
overwritten by the return value of copy_to_user.
Only call copy_to_user when wlan_hdd_qcmbr_command returns 0.

Change-Id: Ie75b3f7329d89766641caec1f377f38127937976
CRs-Fixed: 965103

core/hdd/src/wlan_hdd_ftm.c

@@ -210,17 +210,18 @@ static int wlan_hdd_qcmbr_command(hdd_adapter_t *adapter,
 
 	case ATH_XIOCTL_UNIFIED_UTF_RSP: {
 		pqcmbr_data->copy_to_user = 1;
+
+		spin_lock_bh(&qcmbr_queue_lock);
 		if (!list_empty(&qcmbr_queue_head)) {
-			spin_lock_bh(&qcmbr_queue_lock);
 			qcmbr_buf = list_first_entry(&qcmbr_queue_head,
 						     qcmbr_queue_t,
 						     list);
 			list_del(&qcmbr_buf->list);
-			spin_unlock_bh(&qcmbr_queue_lock);
 			ret = 0;
 		} else {
 			ret = -1;
 		}
+		spin_unlock_bh(&qcmbr_queue_lock);
 
 		if (!ret) {
 			memcpy(pqcmbr_data->buf, qcmbr_buf->utf_buf,
@@ -260,7 +261,7 @@ static int wlan_hdd_qcmbr_compat_ioctl(hdd_adapter_t *adapter,
 	}
 
 	ret = wlan_hdd_qcmbr_command(adapter, qcmbr_data);
-	if (qcmbr_data->copy_to_user) {
+	if ((ret == 0) && qcmbr_data->copy_to_user) {
 		ret = copy_to_user(ifr->ifr_data, qcmbr_data->buf,
 				   (MAX_UTF_LENGTH + 4));
 	}
@@ -299,7 +300,7 @@ static int wlan_hdd_qcmbr_ioctl(hdd_adapter_t *adapter, struct ifreq *ifr)
 	}
 
 	ret = wlan_hdd_qcmbr_command(adapter, qcmbr_data);
-	if (qcmbr_data->copy_to_user) {
+	if ((ret == 0) && qcmbr_data->copy_to_user) {
 		ret = copy_to_user(ifr->ifr_data, qcmbr_data->buf,
 				   (MAX_UTF_LENGTH + 4));
 	}