From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932823AbcHNL3w (ORCPT ); Sun, 14 Aug 2016 07:29:52 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52323 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932969AbcHNL3s (ORCPT ); Sun, 14 Aug 2016 07:29:48 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Dmitry Torokhov" , "Cameron Gutman" , "Pavel Rojtberg" Date: Sat, 13 Aug 2016 18:42:58 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 35/94] Input: xpad - prevent spurious input from wired Xbox 360 controllers In-Reply-To: X-SA-Exim-Connect-IP: 92.40.249.202 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.82-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Cameron Gutman commit 1ff5fa3c6732f08e01ae12f12286d4728c9e4d86 upstream. After initially connecting a wired Xbox 360 controller or sending it a command to change LEDs, a status/response packet is interpreted as controller input. This causes the state of buttons represented in byte 2 of the controller data packet to be incorrect until the next valid input packet. Wireless Xbox 360 controllers are not affected. Writing a new value to the LED device while holding the Start button and running jstest is sufficient to reproduce this bug. An event will come through with the Start button released. Xboxdrv also won't attempt to read controller input from a packet where byte 0 is non-zero. It also checks that byte 1 is 0x14, but that value differs between wired and wireless controllers and this code is shared by both. I think just checking byte 0 is enough to eliminate unwanted packets. The following are some examples of 3-byte status packets I saw: 01 03 02 02 03 00 03 03 03 08 03 00 Signed-off-by: Cameron Gutman Signed-off-by: Pavel Rojtberg Signed-off-by: Dmitry Torokhov [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/input/joystick/xpad.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/input/joystick/xpad.c +++ b/drivers/input/joystick/xpad.c @@ -368,6 +368,10 @@ static void xpad360_process_packet(struc { struct input_dev *dev = xpad->dev; + /* valid pad data */ + if (data[0] != 0x00) + return; + /* digital pad */ if (xpad->mapping & MAP_DPAD_TO_BUTTONS) { /* dpad as buttons (left, right, up, down) */