From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DC935C6FD1F for ; Fri, 10 Mar 2023 15:16:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234125AbjCJPQO (ORCPT ); Fri, 10 Mar 2023 10:16:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232918AbjCJPP7 (ORCPT ); Fri, 10 Mar 2023 10:15:59 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B75B26C0F for ; Fri, 10 Mar 2023 07:06:55 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6B5B561A41 for ; Fri, 10 Mar 2023 15:06:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F6CBC4339B; Fri, 10 Mar 2023 15:06:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678460814; bh=n1qF7fzpWNzZ5zZTD0zbhX1zKEYefHOlgum6rwpaJD0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pKlWHTPxdwEBBc4+wF9F5XzqLUA0b4kk9YxclmCtZe2U2WE8jrN64Eo6GVm27DQJc TwURk/EQlbxz/pvXKDXBZLThBysO3aLz7rNamDJvV897eAshGjpHM/gcUB8/a6JZlp 0pJgBX3njq8fa5Glh2PHaZDugOLj7w/ktLpAWvzA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Hua , Guenter Roeck , Wim Van Sebroeck , Sasha Levin Subject: [PATCH 5.10 460/529] watchdog: pcwd_usb: Fix attempting to access uninitialized memory Date: Fri, 10 Mar 2023 14:40:03 +0100 Message-Id: <20230310133826.212297437@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133804.978589368@linuxfoundation.org> References: <20230310133804.978589368@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Li Hua [ Upstream commit 7d06c07c67100fd0f8e6b3ab7145ce789f788117 ] The stack variable msb and lsb may be used uninitialized in function usb_pcwd_get_temperature and usb_pcwd_get_timeleft when usb card no response. The build waring is: drivers/watchdog/pcwd_usb.c:336:22: error: ‘lsb’ is used uninitialized in this function [-Werror=uninitialized] *temperature = (lsb * 9 / 5) + 32; ~~~~^~~ drivers/watchdog/pcwd_usb.c:328:21: note: ‘lsb’ was declared here unsigned char msb, lsb; ^~~ cc1: all warnings being treated as errors scripts/Makefile.build:250: recipe for target 'drivers/watchdog/pcwd_usb.o' failed make[3]: *** [drivers/watchdog/pcwd_usb.o] Error 1 Fixes: b7e04f8c61a4 ("mv watchdog tree under drivers") Signed-off-by: Li Hua Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20221116020706.70847-1-hucool.lihua@huawei.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin --- drivers/watchdog/pcwd_usb.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/watchdog/pcwd_usb.c b/drivers/watchdog/pcwd_usb.c index 1bdaf17c1d38d..8202f0a6b0935 100644 --- a/drivers/watchdog/pcwd_usb.c +++ b/drivers/watchdog/pcwd_usb.c @@ -325,7 +325,8 @@ static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t) static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature) { - unsigned char msb, lsb; + unsigned char msb = 0x00; + unsigned char lsb = 0x00; usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb); @@ -341,7 +342,8 @@ static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left) { - unsigned char msb, lsb; + unsigned char msb = 0x00; + unsigned char lsb = 0x00; /* Read the time that's left before rebooting */ /* Note: if the board is not yet armed then we will read 0xFFFF */ -- 2.39.2