Re: [PATCH] RFC: Bluetooth: missed cpu_to_le16 conversion in hci_init4_req

[Marcel Holtmann]

Hi Simon,

>> It looks like in hci_init4_req() the request is being
>> initialised from cpu-endian data but the packet is specified
>> to be little-endian. This causes an warning from sparse due
>> to __le16 to u16 conversion.
>> 
>> Fix this by using cpu_to_le16() on the two fields in the packet.
>> 
>> net/bluetooth/hci_core.c:845:27: warning: incorrect type in assignment (different base types)
>> net/bluetooth/hci_core.c:845:27:    expected restricted __le16 [usertype] tx_len
>> net/bluetooth/hci_core.c:845:27:    got unsigned short [usertype] le_max_tx_len
>> net/bluetooth/hci_core.c:846:28: warning: incorrect type in assignment (different base types)
>> net/bluetooth/hci_core.c:846:28:    expected restricted __le16 [usertype] tx_time
>> net/bluetooth/hci_core.c:846:28:    got unsigned short [usertype] le_max_tx_time
>> 
>> Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
>> ---
>> Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx>
>> Cc: Johan Hedberg <johan.hedberg@xxxxxxxxx>
>> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
>> Cc: linux-bluetooth@xxxxxxxxxxxxxxx
>> Cc: netdev@xxxxxxxxxxxxxxx
>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>> ---
>> net/bluetooth/hci_core.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
>> index 04bc79359a17..b2559d4bed81 100644
>> --- a/net/bluetooth/hci_core.c
>> +++ b/net/bluetooth/hci_core.c
>> @@ -842,8 +842,8 @@ static int hci_init4_req(struct hci_request *req, unsigned long opt)
>> 	if (hdev->le_features[0] & HCI_LE_DATA_LEN_EXT) {
>> 		struct hci_cp_le_write_def_data_len cp;
>> 
>> -		cp.tx_len = hdev->le_max_tx_len;
>> -		cp.tx_time = hdev->le_max_tx_time;
>> +		cp.tx_len = cpu_to_le16(hdev->le_max_tx_len);
>> +		cp.tx_time = cpu_to_le16(hdev->le_max_tx_time);
> 
> I would suggest that the naming of the le_ fields of struct hci_dev
> implies that the values stored in those fields should be little endian
> (but those that are more than bone byte wide are not).

the le_ stands for Low Energy and not for Little Endian.

Regards

Marcel