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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 8034BC433E0 for ; Wed, 24 Mar 2021 18:43:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53321619BB for ; Wed, 24 Mar 2021 18:43:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237597AbhCXSnO (ORCPT ); Wed, 24 Mar 2021 14:43:14 -0400 Received: from mga04.intel.com ([192.55.52.120]:57980 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237598AbhCXSm7 (ORCPT ); Wed, 24 Mar 2021 14:42:59 -0400 IronPort-SDR: 2WTxByD4qvYRrZRYG0j9IpCl9FHw4p1KO8C0Y2jeldT3LJaToe+d/GgGGI5WKtfHCkfDNzk1kC uEAv7sIZfCPQ== X-IronPort-AV: E=McAfee;i="6000,8403,9933"; a="188469687" X-IronPort-AV: E=Sophos;i="5.81,275,1610438400"; d="scan'208";a="188469687" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2021 11:42:59 -0700 IronPort-SDR: //PXagpZka724rzCYPJkuPQg8GC3CvIT+idH94eQjhvv5X0hlaMN6OBcwucgj69H+T/0dehZxF MidM/1Q+qXgw== X-IronPort-AV: E=Sophos;i="5.81,275,1610438400"; d="scan'208";a="514299493" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2021 11:42:58 -0700 Date: Wed, 24 Mar 2021 11:42:57 -0700 From: Ira Weiny To: Robert Richter Cc: Alison Schofield , Vishal Verma , Ben Widawsky , Dan Williams , linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] cxl/mem: Force array size of mem_commands[] to CXL_MEM_COMMAND_ID_MAX Message-ID: <20210324184257.GV3014244@iweiny-DESK2.sc.intel.com> References: <20210324141635.22335-1-rrichter@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210324141635.22335-1-rrichter@amd.com> User-Agent: Mutt/1.11.1 (2018-12-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 24, 2021 at 03:16:35PM +0100, Robert Richter wrote: > Typically the mem_commands[] array is in sync with 'enum { CXL_CMDS }'. > Current code works well. > > However, the array size of mem_commands[] may not strictly be the same > as CXL_MEM_COMMAND_ID_MAX. E.g. if a new CXL_CMD() is added that is > guarded by #ifdefs, the array could be shorter. This could lead then > further to an out-of-bounds array access in cxl_validate_cmd_from_user(). > > Fix this by forcing the array size to CXL_MEM_COMMAND_ID_MAX. This > also adds range checks for array items in mem_commands[] at compile > time. Can't we use ARRAY_SIZE? Ira > > Signed-off-by: Robert Richter > --- > drivers/cxl/mem.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c > index 244cb7d89678..ecfc9ccdba8d 100644 > --- a/drivers/cxl/mem.c > +++ b/drivers/cxl/mem.c > @@ -169,7 +169,7 @@ struct cxl_mem_command { > * table will be validated against the user's input. For example, if size_in is > * 0, and the user passed in 1, it is an error. > */ > -static struct cxl_mem_command mem_commands[] = { > +static struct cxl_mem_command mem_commands[CXL_MEM_COMMAND_ID_MAX] = { > CXL_CMD(IDENTIFY, 0, 0x43, CXL_CMD_FLAG_FORCE_ENABLE), > #ifdef CONFIG_CXL_MEM_RAW_COMMANDS > CXL_CMD(RAW, ~0, ~0, 0), > -- > 2.29.2 >