From patchwork Tue Jan 6 23:17:15 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 5578021 X-Patchwork-Delegate: jikos@jikos.cz Return-Path: X-Original-To: patchwork-linux-input@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id C9066BF6C3 for ; Tue, 6 Jan 2015 23:25:07 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 18B072021A for ; Tue, 6 Jan 2015 23:25:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 447F120211 for ; Tue, 6 Jan 2015 23:25:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751070AbbAFXZF (ORCPT ); Tue, 6 Jan 2015 18:25:05 -0500 Received: from gw02.mail.saunalahti.fi ([195.197.172.116]:57884 "EHLO gw02.mail.saunalahti.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750807AbbAFXZE (ORCPT ); Tue, 6 Jan 2015 18:25:04 -0500 X-Greylist: delayed 460 seconds by postgrey-1.27 at vger.kernel.org; Tue, 06 Jan 2015 18:25:04 EST Received: from localhost.localdomain (a91-152-110-231.elisa-laajakaista.fi [91.152.110.231]) by gw02.mail.saunalahti.fi (Postfix) with ESMTP id 86B1140063; Wed, 7 Jan 2015 01:17:18 +0200 (EET) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by localhost.localdomain (8.14.7/8.14.7) with ESMTP id t06NHIDP027702; Wed, 7 Jan 2015 01:17:18 +0200 Received: (from andy@localhost) by localhost.localdomain (8.14.7/8.14.7/Submit) id t06NHGhC027701; Wed, 7 Jan 2015 01:17:16 +0200 X-Authentication-Warning: localhost.localdomain: andy set sender to andy.shevchenko@gmail.com using -f From: Andy Shevchenko To: Jiri Kosina , linux-input@vger.kernel.org Cc: Andy Shevchenko Subject: [PATCH] HID: core: don't use negative operands when shift Date: Wed, 7 Jan 2015 01:17:15 +0200 Message-Id: <1420586235-27660-1-git-send-email-andy.shevchenko@gmail.com> X-Mailer: git-send-email 1.8.3.101.g727a46b Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, FREEMAIL_FROM,RCVD_IN_DNSWL_HI,T_RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The recent C standard in 6.5.7 paragraph 4 defines that operands for bitwise shift operators should be non-negative, otherwise it's an undefined behaviour. Signed-off-by: Andy Shevchenko --- drivers/hid/hid-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index f2a4879..99307f0 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1027,7 +1027,7 @@ static s32 snto32(__u32 value, unsigned n) case 16: return ((__s16)value); case 32: return ((__s32)value); } - return value & (1 << (n - 1)) ? value | (-1 << n) : value; + return value & (1 << (n - 1)) ? value | (~0U << n) : value; } s32 hid_snto32(__u32 value, unsigned n)