From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935164AbeAHQsi (ORCPT + 1 other); Mon, 8 Jan 2018 11:48:38 -0500 Received: from mga09.intel.com ([134.134.136.24]:47838 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935148AbeAHQsf (ORCPT ); Mon, 8 Jan 2018 11:48:35 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,330,1511856000"; d="scan'208";a="18423254" From: Vinod Koul To: Greg KH Cc: LKML , Sanyog Kale , Colin Ian King Subject: [PATCH 1/3] soundwire: fix sign extension when shifting buf[2] 24 places Date: Mon, 8 Jan 2018 22:22:42 +0530 Message-Id: <1515430364-12079-1-git-send-email-vinod.koul@intel.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: From: Colin Ian King The buf[2] left shift by 24 bits is promoted to int (32 bit signed) and then signed-extended to unsigned long long. Hence if the upper bit to buf[2] is set then all the upper bits of addr end up as 1. Fix this by casting it to u64 before shifting it. Also replace the unsigned long long casts to u64 casts to match the same type of addr. Detected by CoverityScan, CID#1463147 ("Unintended sign extension") Fixes: d52d7a1be02c ("soundwire: Add Slave status handling helpers") Signed-off-by: Colin Ian King Acked-by: Vinod Koul --- drivers/soundwire/bus.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 4c345197eb55..7211ecc62015 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -522,8 +522,8 @@ static int sdw_program_device_num(struct sdw_bus *bus) * bits to avoid truncation due to size limit. */ addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) | - (buf[2] << 24) | ((unsigned long long)buf[1] << 32) | - ((unsigned long long)buf[0] << 40); + ((u64)buf[2] << 24) | ((u64)buf[1] << 32) | + ((u64)buf[0] << 40); sdw_extract_slave_id(bus, addr, &id); -- 2.7.4