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 X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F92EC67839 for ; Mon, 10 Dec 2018 20:04:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3815120821 for ; Mon, 10 Dec 2018 20:04:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3815120821 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729710AbeLJUEE (ORCPT ); Mon, 10 Dec 2018 15:04:04 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:43712 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727302AbeLJUED (ORCPT ); Mon, 10 Dec 2018 15:04:03 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id D760A1473AE8E; Mon, 10 Dec 2018 12:04:02 -0800 (PST) Date: Mon, 10 Dec 2018 12:04:02 -0800 (PST) Message-Id: <20181210.120402.2087888281534527051.davem@davemloft.net> To: yuehaibing@huawei.com Cc: h.morris@cascoda.com, alex.aring@gmail.com, stefan@datenfreihafen.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-wpan@vger.kernel.org Subject: Re: [PATCH net-next] ieee802154: ca8210: remove a dead branch From: David Miller In-Reply-To: <20181210113443.22796-1-yuehaibing@huawei.com> References: <20181210113443.22796-1-yuehaibing@huawei.com> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 10 Dec 2018 12:04:03 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: YueHaibing Date: Mon, 10 Dec 2018 19:34:43 +0800 > Fix follwing gcc warning: > > drivers/net/ieee802154/ca8210.c:730:10: warning: > comparison is always false due to limited range of data type [-Wtype-limits] > > the variable 'len' is of type u8 and cannot greater than > CA8210_SPI_BUF_SIZE , which is 256. > > Signed-off-by: YueHaibing Then bug is the variable type here. We are reading a u8 from buf[], then adding 2, which can overflow. 'len' should be an unsigned int or similar.