Bluetooth: Fix HCI H5 corrupted ack value

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>

This commit is contained in:

Loic Poulain

2014-08-08 19:07:16 +02:00

committed by

Greg Kroah-Hartman

parent 28330aa4e0

commit 90f9a6a427

1 changed files with 1 additions and 1 deletions

									
										drivers/bluetooth/hci_h5.c
									
		+1
		-1
	
												View File
												
				@@ -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)