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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 616A0C3279B for ; Wed, 4 Jul 2018 11:59:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 032AD208C2 for ; Wed, 4 Jul 2018 11:59:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 032AD208C2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lip6.fr 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 S934252AbeGDL7S (ORCPT ); Wed, 4 Jul 2018 07:59:18 -0400 Received: from mail2-relais-roc.national.inria.fr ([192.134.164.83]:57119 "EHLO mail2-relais-roc.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933113AbeGDL7R (ORCPT ); Wed, 4 Jul 2018 07:59:17 -0400 X-IronPort-AV: E=Sophos;i="5.51,306,1526335200"; d="scan'208";a="335413769" Received: from wl6-20.enseeiht.fr (HELO hadrien.local) ([147.127.193.20]) by mail2-relais-roc.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Jul 2018 13:59:15 +0200 Date: Wed, 4 Jul 2018 13:59:14 +0200 (CEST) From: Julia Lawall X-X-Sender: jll@hadrien To: Dan Carpenter cc: Tomas Winkler , Alexander Usyskin , Arnd Bergmann , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] mei: bus: type promotion bug in mei_nfc_if_version() In-Reply-To: <20180704093449.vryluk7khaudstgp@kili.mountain> Message-ID: References: <20180704093449.vryluk7khaudstgp@kili.mountain> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 4 Jul 2018, Dan Carpenter wrote: > We accidentally removed the check for negative returns without > considering the issue of type promotion. The "if_version_length" > variable is type size_t so if __mei_cl_recv() returns a negative then > "bytes_recv" is type promoted to a high positive value and treated as > success. > > Fixes: 582ab27a063a ("mei: bus: fix received data size check in NFC fixup") > Signed-off-by: Dan Carpenter > > diff --git a/drivers/misc/mei/bus-fixup.c b/drivers/misc/mei/bus-fixup.c > index 0208c4b027c5..fa0236a5e59a 100644 > --- a/drivers/misc/mei/bus-fixup.c > +++ b/drivers/misc/mei/bus-fixup.c > @@ -267,7 +267,7 @@ static int mei_nfc_if_version(struct mei_cl *cl, > > ret = 0; > bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length, 0); > - if (bytes_recv < if_version_length) { > + if (bytes_recv < 0 || bytes_recv < if_version_length) { Is this preferred to adding an int cast? julia > dev_err(bus->dev, "Could not read IF version\n"); > ret = -EIO; > goto err; > -- > To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >