| From 4807b51895dce8aa650ebebc51fa4a795ed6b8b8 Mon Sep 17 00:00:00 2001 |
| From: Loic Poulain <loic.poulain@intel.com> |
| Date: Fri, 8 Aug 2014 19:07:16 +0200 |
| Subject: Bluetooth: Fix HCI H5 corrupted ack value |
| |
| From: Loic Poulain <loic.poulain@intel.com> |
| |
| commit 4807b51895dce8aa650ebebc51fa4a795ed6b8b8 upstream. |
| |
| In this expression: seq = (seq - 1) % 8 |
| seq (u8) is implicitly converted to an int in the arithmetic operation. |
| So if seq value is 0, operation is ((0 - 1) % 8) => (-1 % 8) => -1. |
| The new seq value is 0xff which is an invalid ACK value, we expect 0x07. |
| It leads to frequent dropped ACK and retransmission. |
| Fix this by using '&' binary operator instead of '%'. |
| |
| Signed-off-by: Loic Poulain <loic.poulain@intel.com> |
| Signed-off-by: Marcel Holtmann <marcel@holtmann.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/bluetooth/hci_h5.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/bluetooth/hci_h5.c |
| +++ b/drivers/bluetooth/hci_h5.c |
| @@ -237,7 +237,7 @@ static void h5_pkt_cull(struct h5 *h5) |
| break; |
| |
| to_remove--; |
| - seq = (seq - 1) % 8; |
| + seq = (seq - 1) & 0x07; |
| } |
| |
| if (seq != h5->rx_ack) |
