From mboxrd@z Thu Jan 1 00:00:00 1970 From: nick.dyer@itdev.co.uk Subject: [PATCH] Input: atmel_mxt_ts - fix invalid return from mxt_get_bootloader_version Date: Thu, 29 May 2014 13:34:22 +0100 Message-ID: <1401366862-6295-1-git-send-email-nick.dyer@itdev.co.uk> References: <20140521122624.GB23396@mwanda> Return-path: Received: from kdh-gw.itdev.co.uk ([89.21.227.133]:59876 "EHLO hermes.kdh.itdev.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755718AbaE2MjP (ORCPT ); Thu, 29 May 2014 08:39:15 -0400 In-Reply-To: <20140521122624.GB23396@mwanda> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov Cc: Dan Carpenter , linux-input@vger.kernel.org, Nick Dyer From: Nick Dyer The patch e57a66aa8534: "Input: atmel_mxt_ts - read and report bootloader version" from May 18, 2014, leads to the following static checker warning: drivers/input/touchscreen/atmel_mxt_ts.c:437 mxt_get_bootloader_version() warn: signedness bug returning '(-5)' drivers/input/touchscreen/atmel_mxt_ts.c 429 static u8 mxt_get_bootloader_version(struct mxt_data *data, u8 val) 430 { 431 struct device *dev = &data->client->dev; 432 u8 buf[3]; 433 434 if (val & MXT_BOOT_EXTENDED_ID) { 435 if (mxt_bootloader_read(data, &buf[0], 3) != 0) { 436 dev_err(dev, "%s: i2c failure\n", __func__); 437 return -EIO; ^^^^ This gets truncated into a number from 0-255 and anyway the caller doesn't check for errors. (reported by Dan Carpenter) Signed-off-by: Nick Dyer --- drivers/input/touchscreen/atmel_mxt_ts.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index fb0e006..693b163 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -435,7 +435,7 @@ static u8 mxt_get_bootloader_version(struct mxt_data *data, u8 val) if (val & MXT_BOOT_EXTENDED_ID) { if (mxt_bootloader_read(data, &buf[0], 3) != 0) { dev_err(dev, "%s: i2c failure\n", __func__); - return -EIO; + return val; } dev_dbg(dev, "Bootloader ID:%d Version:%d\n", buf[1], buf[2]); -- 1.8.3.2