From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:36500 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731958AbeK3Be6 (ORCPT ); Thu, 29 Nov 2018 20:34:58 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+13cb3b01d0784e4ffc3f@syzkaller.appspotmail.com, Benjamin Tissoires , Peter Hutterer , Dmitry Torokhov Subject: [PATCH 4.19 032/110] Input: synaptics - avoid using uninitialized variable when probing Date: Thu, 29 Nov 2018 15:12:03 +0100 Message-Id: <20181129135922.565401586@linuxfoundation.org> In-Reply-To: <20181129135921.231283053@linuxfoundation.org> References: <20181129135921.231283053@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Torokhov commit f39f8688888ae74fa8deae2d01289b69b4727394 upstream. synaptics_detect() does not check whether sending commands to the device succeeds and instead relies on getting unique data from the device. Let's make sure we seed entire buffer with zeroes to make sure we will not use garbage on stack that just happen to be 0x47. Reported-by: syzbot+13cb3b01d0784e4ffc3f@syzkaller.appspotmail.com Reviewed-by: Benjamin Tissoires Reviewed-by: Peter Hutterer Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman --- drivers/input/mouse/synaptics.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/input/mouse/synaptics.c +++ b/drivers/input/mouse/synaptics.c @@ -99,9 +99,7 @@ static int synaptics_mode_cmd(struct psm int synaptics_detect(struct psmouse *psmouse, bool set_properties) { struct ps2dev *ps2dev = &psmouse->ps2dev; - u8 param[4]; - - param[0] = 0; + u8 param[4] = { 0 }; ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES); ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);